1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * NET3 Protocol independent device support routines. 4 * 5 * Derived from the non IP parts of dev.c 1.0.19 6 * Authors: Ross Biro 7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 8 * Mark Evans, <evansmp@uhura.aston.ac.uk> 9 * 10 * Additional Authors: 11 * Florian la Roche <rzsfl@rz.uni-sb.de> 12 * Alan Cox <gw4pts@gw4pts.ampr.org> 13 * David Hinds <dahinds@users.sourceforge.net> 14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 15 * Adam Sulmicki <adam@cfar.umd.edu> 16 * Pekka Riikonen <priikone@poesidon.pspt.fi> 17 * 18 * Changes: 19 * D.J. Barrow : Fixed bug where dev->refcnt gets set 20 * to 2 if register_netdev gets called 21 * before net_dev_init & also removed a 22 * few lines of code in the process. 23 * Alan Cox : device private ioctl copies fields back. 24 * Alan Cox : Transmit queue code does relevant 25 * stunts to keep the queue safe. 26 * Alan Cox : Fixed double lock. 27 * Alan Cox : Fixed promisc NULL pointer trap 28 * ???????? : Support the full private ioctl range 29 * Alan Cox : Moved ioctl permission check into 30 * drivers 31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 32 * Alan Cox : 100 backlog just doesn't cut it when 33 * you start doing multicast video 8) 34 * Alan Cox : Rewrote net_bh and list manager. 35 * Alan Cox : Fix ETH_P_ALL echoback lengths. 36 * Alan Cox : Took out transmit every packet pass 37 * Saved a few bytes in the ioctl handler 38 * Alan Cox : Network driver sets packet type before 39 * calling netif_rx. Saves a function 40 * call a packet. 41 * Alan Cox : Hashed net_bh() 42 * Richard Kooijman: Timestamp fixes. 43 * Alan Cox : Wrong field in SIOCGIFDSTADDR 44 * Alan Cox : Device lock protection. 45 * Alan Cox : Fixed nasty side effect of device close 46 * changes. 47 * Rudi Cilibrasi : Pass the right thing to 48 * set_mac_address() 49 * Dave Miller : 32bit quantity for the device lock to 50 * make it work out on a Sparc. 51 * Bjorn Ekwall : Added KERNELD hack. 52 * Alan Cox : Cleaned up the backlog initialise. 53 * Craig Metz : SIOCGIFCONF fix if space for under 54 * 1 device. 55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 56 * is no device open function. 57 * Andi Kleen : Fix error reporting for SIOCGIFCONF 58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 59 * Cyrus Durgin : Cleaned for KMOD 60 * Adam Sulmicki : Bug Fix : Network Device Unload 61 * A network device unload needs to purge 62 * the backlog queue. 63 * Paul Rusty Russell : SIOCSIFNAME 64 * Pekka Riikonen : Netdev boot-time settings code 65 * Andrew Morton : Make unregister_netdevice wait 66 * indefinitely on dev->refcnt 67 * J Hadi Salim : - Backlog queue sampling 68 * - netif_rx() feedback 69 */ 70 71 #include <linux/uaccess.h> 72 #include <linux/bitmap.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/isolation.h> 81 #include <linux/sched/mm.h> 82 #include <linux/smpboot.h> 83 #include <linux/mutex.h> 84 #include <linux/rwsem.h> 85 #include <linux/string.h> 86 #include <linux/mm.h> 87 #include <linux/socket.h> 88 #include <linux/sockios.h> 89 #include <linux/errno.h> 90 #include <linux/interrupt.h> 91 #include <linux/if_ether.h> 92 #include <linux/netdevice.h> 93 #include <linux/etherdevice.h> 94 #include <linux/ethtool.h> 95 #include <linux/ethtool_netlink.h> 96 #include <linux/skbuff.h> 97 #include <linux/kthread.h> 98 #include <linux/bpf.h> 99 #include <linux/bpf_trace.h> 100 #include <net/net_namespace.h> 101 #include <net/sock.h> 102 #include <net/busy_poll.h> 103 #include <linux/rtnetlink.h> 104 #include <linux/stat.h> 105 #include <net/dsa.h> 106 #include <net/dst.h> 107 #include <net/dst_metadata.h> 108 #include <net/gro.h> 109 #include <net/netdev_queues.h> 110 #include <net/pkt_sched.h> 111 #include <net/pkt_cls.h> 112 #include <net/checksum.h> 113 #include <net/xfrm.h> 114 #include <net/tcx.h> 115 #include <linux/highmem.h> 116 #include <linux/init.h> 117 #include <linux/module.h> 118 #include <linux/netpoll.h> 119 #include <linux/rcupdate.h> 120 #include <linux/delay.h> 121 #include <net/iw_handler.h> 122 #include <asm/current.h> 123 #include <linux/audit.h> 124 #include <linux/dmaengine.h> 125 #include <linux/err.h> 126 #include <linux/ctype.h> 127 #include <linux/if_arp.h> 128 #include <linux/if_vlan.h> 129 #include <linux/ip.h> 130 #include <net/ip.h> 131 #include <net/mpls.h> 132 #include <linux/ipv6.h> 133 #include <linux/in.h> 134 #include <linux/jhash.h> 135 #include <linux/random.h> 136 #include <trace/events/napi.h> 137 #include <trace/events/net.h> 138 #include <trace/events/skb.h> 139 #include <trace/events/qdisc.h> 140 #include <trace/events/xdp.h> 141 #include <linux/inetdevice.h> 142 #include <linux/cpu_rmap.h> 143 #include <linux/static_key.h> 144 #include <linux/hashtable.h> 145 #include <linux/vmalloc.h> 146 #include <linux/if_macvlan.h> 147 #include <linux/errqueue.h> 148 #include <linux/hrtimer.h> 149 #include <linux/netfilter_netdev.h> 150 #include <linux/crash_dump.h> 151 #include <linux/sctp.h> 152 #include <net/udp_tunnel.h> 153 #include <linux/net_namespace.h> 154 #include <linux/indirect_call_wrapper.h> 155 #include <net/devlink.h> 156 #include <linux/pm_runtime.h> 157 #include <linux/prandom.h> 158 #include <linux/once_lite.h> 159 #include <net/netdev_rx_queue.h> 160 #include <net/page_pool/types.h> 161 #include <net/page_pool/helpers.h> 162 #include <net/rps.h> 163 #include <linux/phy_link_topology.h> 164 165 #include "dev.h" 166 #include "devmem.h" 167 #include "net-sysfs.h" 168 169 static DEFINE_SPINLOCK(ptype_lock); 170 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 171 172 static int netif_rx_internal(struct sk_buff *skb); 173 static int call_netdevice_notifiers_extack(unsigned long val, 174 struct net_device *dev, 175 struct netlink_ext_ack *extack); 176 177 static DEFINE_MUTEX(ifalias_mutex); 178 179 /* protects napi_hash addition/deletion and napi_gen_id */ 180 static DEFINE_SPINLOCK(napi_hash_lock); 181 182 static unsigned int napi_gen_id = NR_CPUS; 183 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 184 185 static inline void dev_base_seq_inc(struct net *net) 186 { 187 unsigned int val = net->dev_base_seq + 1; 188 189 WRITE_ONCE(net->dev_base_seq, val ?: 1); 190 } 191 192 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 193 { 194 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 195 196 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 197 } 198 199 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 200 { 201 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 202 } 203 204 #ifndef CONFIG_PREEMPT_RT 205 206 static DEFINE_STATIC_KEY_FALSE(use_backlog_threads_key); 207 208 static int __init setup_backlog_napi_threads(char *arg) 209 { 210 static_branch_enable(&use_backlog_threads_key); 211 return 0; 212 } 213 early_param("thread_backlog_napi", setup_backlog_napi_threads); 214 215 static bool use_backlog_threads(void) 216 { 217 return static_branch_unlikely(&use_backlog_threads_key); 218 } 219 220 #else 221 222 static bool use_backlog_threads(void) 223 { 224 return true; 225 } 226 227 #endif 228 229 static inline void backlog_lock_irq_save(struct softnet_data *sd, 230 unsigned long *flags) 231 { 232 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 233 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 234 else 235 local_irq_save(*flags); 236 } 237 238 static inline void backlog_lock_irq_disable(struct softnet_data *sd) 239 { 240 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 241 spin_lock_irq(&sd->input_pkt_queue.lock); 242 else 243 local_irq_disable(); 244 } 245 246 static inline void backlog_unlock_irq_restore(struct softnet_data *sd, 247 unsigned long *flags) 248 { 249 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 250 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 251 else 252 local_irq_restore(*flags); 253 } 254 255 static inline void backlog_unlock_irq_enable(struct softnet_data *sd) 256 { 257 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 258 spin_unlock_irq(&sd->input_pkt_queue.lock); 259 else 260 local_irq_enable(); 261 } 262 263 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 264 const char *name) 265 { 266 struct netdev_name_node *name_node; 267 268 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 269 if (!name_node) 270 return NULL; 271 INIT_HLIST_NODE(&name_node->hlist); 272 name_node->dev = dev; 273 name_node->name = name; 274 return name_node; 275 } 276 277 static struct netdev_name_node * 278 netdev_name_node_head_alloc(struct net_device *dev) 279 { 280 struct netdev_name_node *name_node; 281 282 name_node = netdev_name_node_alloc(dev, dev->name); 283 if (!name_node) 284 return NULL; 285 INIT_LIST_HEAD(&name_node->list); 286 return name_node; 287 } 288 289 static void netdev_name_node_free(struct netdev_name_node *name_node) 290 { 291 kfree(name_node); 292 } 293 294 static void netdev_name_node_add(struct net *net, 295 struct netdev_name_node *name_node) 296 { 297 hlist_add_head_rcu(&name_node->hlist, 298 dev_name_hash(net, name_node->name)); 299 } 300 301 static void netdev_name_node_del(struct netdev_name_node *name_node) 302 { 303 hlist_del_rcu(&name_node->hlist); 304 } 305 306 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 307 const char *name) 308 { 309 struct hlist_head *head = dev_name_hash(net, name); 310 struct netdev_name_node *name_node; 311 312 hlist_for_each_entry(name_node, head, hlist) 313 if (!strcmp(name_node->name, name)) 314 return name_node; 315 return NULL; 316 } 317 318 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 319 const char *name) 320 { 321 struct hlist_head *head = dev_name_hash(net, name); 322 struct netdev_name_node *name_node; 323 324 hlist_for_each_entry_rcu(name_node, head, hlist) 325 if (!strcmp(name_node->name, name)) 326 return name_node; 327 return NULL; 328 } 329 330 bool netdev_name_in_use(struct net *net, const char *name) 331 { 332 return netdev_name_node_lookup(net, name); 333 } 334 EXPORT_SYMBOL(netdev_name_in_use); 335 336 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 337 { 338 struct netdev_name_node *name_node; 339 struct net *net = dev_net(dev); 340 341 name_node = netdev_name_node_lookup(net, name); 342 if (name_node) 343 return -EEXIST; 344 name_node = netdev_name_node_alloc(dev, name); 345 if (!name_node) 346 return -ENOMEM; 347 netdev_name_node_add(net, name_node); 348 /* The node that holds dev->name acts as a head of per-device list. */ 349 list_add_tail_rcu(&name_node->list, &dev->name_node->list); 350 351 return 0; 352 } 353 354 static void netdev_name_node_alt_free(struct rcu_head *head) 355 { 356 struct netdev_name_node *name_node = 357 container_of(head, struct netdev_name_node, rcu); 358 359 kfree(name_node->name); 360 netdev_name_node_free(name_node); 361 } 362 363 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 364 { 365 netdev_name_node_del(name_node); 366 list_del(&name_node->list); 367 call_rcu(&name_node->rcu, netdev_name_node_alt_free); 368 } 369 370 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 371 { 372 struct netdev_name_node *name_node; 373 struct net *net = dev_net(dev); 374 375 name_node = netdev_name_node_lookup(net, name); 376 if (!name_node) 377 return -ENOENT; 378 /* lookup might have found our primary name or a name belonging 379 * to another device. 380 */ 381 if (name_node == dev->name_node || name_node->dev != dev) 382 return -EINVAL; 383 384 __netdev_name_node_alt_destroy(name_node); 385 return 0; 386 } 387 388 static void netdev_name_node_alt_flush(struct net_device *dev) 389 { 390 struct netdev_name_node *name_node, *tmp; 391 392 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) { 393 list_del(&name_node->list); 394 netdev_name_node_alt_free(&name_node->rcu); 395 } 396 } 397 398 /* Device list insertion */ 399 static void list_netdevice(struct net_device *dev) 400 { 401 struct netdev_name_node *name_node; 402 struct net *net = dev_net(dev); 403 404 ASSERT_RTNL(); 405 406 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 407 netdev_name_node_add(net, dev->name_node); 408 hlist_add_head_rcu(&dev->index_hlist, 409 dev_index_hash(net, dev->ifindex)); 410 411 netdev_for_each_altname(dev, name_node) 412 netdev_name_node_add(net, name_node); 413 414 /* We reserved the ifindex, this can't fail */ 415 WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL)); 416 417 dev_base_seq_inc(net); 418 } 419 420 /* Device list removal 421 * caller must respect a RCU grace period before freeing/reusing dev 422 */ 423 static void unlist_netdevice(struct net_device *dev) 424 { 425 struct netdev_name_node *name_node; 426 struct net *net = dev_net(dev); 427 428 ASSERT_RTNL(); 429 430 xa_erase(&net->dev_by_index, dev->ifindex); 431 432 netdev_for_each_altname(dev, name_node) 433 netdev_name_node_del(name_node); 434 435 /* Unlink dev from the device chain */ 436 list_del_rcu(&dev->dev_list); 437 netdev_name_node_del(dev->name_node); 438 hlist_del_rcu(&dev->index_hlist); 439 440 dev_base_seq_inc(dev_net(dev)); 441 } 442 443 /* 444 * Our notifier list 445 */ 446 447 static RAW_NOTIFIER_HEAD(netdev_chain); 448 449 /* 450 * Device drivers call our routines to queue packets here. We empty the 451 * queue in the local softnet handler. 452 */ 453 454 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data) = { 455 .process_queue_bh_lock = INIT_LOCAL_LOCK(process_queue_bh_lock), 456 }; 457 EXPORT_PER_CPU_SYMBOL(softnet_data); 458 459 /* Page_pool has a lockless array/stack to alloc/recycle pages. 460 * PP consumers must pay attention to run APIs in the appropriate context 461 * (e.g. NAPI context). 462 */ 463 DEFINE_PER_CPU(struct page_pool *, system_page_pool); 464 465 #ifdef CONFIG_LOCKDEP 466 /* 467 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 468 * according to dev->type 469 */ 470 static const unsigned short netdev_lock_type[] = { 471 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 472 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 473 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 474 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 475 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 476 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 477 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 478 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 479 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 480 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 481 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 482 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 483 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 484 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 485 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 486 487 static const char *const netdev_lock_name[] = { 488 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 489 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 490 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 491 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 492 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 493 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 494 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 495 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 496 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 497 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 498 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 499 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 500 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 501 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 502 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 503 504 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 505 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 506 507 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 508 { 509 int i; 510 511 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 512 if (netdev_lock_type[i] == dev_type) 513 return i; 514 /* the last key is used by default */ 515 return ARRAY_SIZE(netdev_lock_type) - 1; 516 } 517 518 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 519 unsigned short dev_type) 520 { 521 int i; 522 523 i = netdev_lock_pos(dev_type); 524 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 525 netdev_lock_name[i]); 526 } 527 528 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 529 { 530 int i; 531 532 i = netdev_lock_pos(dev->type); 533 lockdep_set_class_and_name(&dev->addr_list_lock, 534 &netdev_addr_lock_key[i], 535 netdev_lock_name[i]); 536 } 537 #else 538 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 539 unsigned short dev_type) 540 { 541 } 542 543 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 544 { 545 } 546 #endif 547 548 /******************************************************************************* 549 * 550 * Protocol management and registration routines 551 * 552 *******************************************************************************/ 553 554 555 /* 556 * Add a protocol ID to the list. Now that the input handler is 557 * smarter we can dispense with all the messy stuff that used to be 558 * here. 559 * 560 * BEWARE!!! Protocol handlers, mangling input packets, 561 * MUST BE last in hash buckets and checking protocol handlers 562 * MUST start from promiscuous ptype_all chain in net_bh. 563 * It is true now, do not change it. 564 * Explanation follows: if protocol handler, mangling packet, will 565 * be the first on list, it is not able to sense, that packet 566 * is cloned and should be copied-on-write, so that it will 567 * change it and subsequent readers will get broken packet. 568 * --ANK (980803) 569 */ 570 571 static inline struct list_head *ptype_head(const struct packet_type *pt) 572 { 573 if (pt->type == htons(ETH_P_ALL)) 574 return pt->dev ? &pt->dev->ptype_all : &net_hotdata.ptype_all; 575 else 576 return pt->dev ? &pt->dev->ptype_specific : 577 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 578 } 579 580 /** 581 * dev_add_pack - add packet handler 582 * @pt: packet type declaration 583 * 584 * Add a protocol handler to the networking stack. The passed &packet_type 585 * is linked into kernel lists and may not be freed until it has been 586 * removed from the kernel lists. 587 * 588 * This call does not sleep therefore it can not 589 * guarantee all CPU's that are in middle of receiving packets 590 * will see the new packet type (until the next received packet). 591 */ 592 593 void dev_add_pack(struct packet_type *pt) 594 { 595 struct list_head *head = ptype_head(pt); 596 597 spin_lock(&ptype_lock); 598 list_add_rcu(&pt->list, head); 599 spin_unlock(&ptype_lock); 600 } 601 EXPORT_SYMBOL(dev_add_pack); 602 603 /** 604 * __dev_remove_pack - remove packet handler 605 * @pt: packet type declaration 606 * 607 * Remove a protocol handler that was previously added to the kernel 608 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 609 * from the kernel lists and can be freed or reused once this function 610 * returns. 611 * 612 * The packet type might still be in use by receivers 613 * and must not be freed until after all the CPU's have gone 614 * through a quiescent state. 615 */ 616 void __dev_remove_pack(struct packet_type *pt) 617 { 618 struct list_head *head = ptype_head(pt); 619 struct packet_type *pt1; 620 621 spin_lock(&ptype_lock); 622 623 list_for_each_entry(pt1, head, list) { 624 if (pt == pt1) { 625 list_del_rcu(&pt->list); 626 goto out; 627 } 628 } 629 630 pr_warn("dev_remove_pack: %p not found\n", pt); 631 out: 632 spin_unlock(&ptype_lock); 633 } 634 EXPORT_SYMBOL(__dev_remove_pack); 635 636 /** 637 * dev_remove_pack - remove packet handler 638 * @pt: packet type declaration 639 * 640 * Remove a protocol handler that was previously added to the kernel 641 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 642 * from the kernel lists and can be freed or reused once this function 643 * returns. 644 * 645 * This call sleeps to guarantee that no CPU is looking at the packet 646 * type after return. 647 */ 648 void dev_remove_pack(struct packet_type *pt) 649 { 650 __dev_remove_pack(pt); 651 652 synchronize_net(); 653 } 654 EXPORT_SYMBOL(dev_remove_pack); 655 656 657 /******************************************************************************* 658 * 659 * Device Interface Subroutines 660 * 661 *******************************************************************************/ 662 663 /** 664 * dev_get_iflink - get 'iflink' value of a interface 665 * @dev: targeted interface 666 * 667 * Indicates the ifindex the interface is linked to. 668 * Physical interfaces have the same 'ifindex' and 'iflink' values. 669 */ 670 671 int dev_get_iflink(const struct net_device *dev) 672 { 673 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 674 return dev->netdev_ops->ndo_get_iflink(dev); 675 676 return READ_ONCE(dev->ifindex); 677 } 678 EXPORT_SYMBOL(dev_get_iflink); 679 680 /** 681 * dev_fill_metadata_dst - Retrieve tunnel egress information. 682 * @dev: targeted interface 683 * @skb: The packet. 684 * 685 * For better visibility of tunnel traffic OVS needs to retrieve 686 * egress tunnel information for a packet. Following API allows 687 * user to get this info. 688 */ 689 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 690 { 691 struct ip_tunnel_info *info; 692 693 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 694 return -EINVAL; 695 696 info = skb_tunnel_info_unclone(skb); 697 if (!info) 698 return -ENOMEM; 699 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 700 return -EINVAL; 701 702 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 703 } 704 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 705 706 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 707 { 708 int k = stack->num_paths++; 709 710 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 711 return NULL; 712 713 return &stack->path[k]; 714 } 715 716 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 717 struct net_device_path_stack *stack) 718 { 719 const struct net_device *last_dev; 720 struct net_device_path_ctx ctx = { 721 .dev = dev, 722 }; 723 struct net_device_path *path; 724 int ret = 0; 725 726 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 727 stack->num_paths = 0; 728 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 729 last_dev = ctx.dev; 730 path = dev_fwd_path(stack); 731 if (!path) 732 return -1; 733 734 memset(path, 0, sizeof(struct net_device_path)); 735 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 736 if (ret < 0) 737 return -1; 738 739 if (WARN_ON_ONCE(last_dev == ctx.dev)) 740 return -1; 741 } 742 743 if (!ctx.dev) 744 return ret; 745 746 path = dev_fwd_path(stack); 747 if (!path) 748 return -1; 749 path->type = DEV_PATH_ETHERNET; 750 path->dev = ctx.dev; 751 752 return ret; 753 } 754 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 755 756 /* must be called under rcu_read_lock(), as we dont take a reference */ 757 static struct napi_struct *napi_by_id(unsigned int napi_id) 758 { 759 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 760 struct napi_struct *napi; 761 762 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 763 if (napi->napi_id == napi_id) 764 return napi; 765 766 return NULL; 767 } 768 769 /* must be called under rcu_read_lock(), as we dont take a reference */ 770 static struct napi_struct * 771 netdev_napi_by_id(struct net *net, unsigned int napi_id) 772 { 773 struct napi_struct *napi; 774 775 napi = napi_by_id(napi_id); 776 if (!napi) 777 return NULL; 778 779 if (WARN_ON_ONCE(!napi->dev)) 780 return NULL; 781 if (!net_eq(net, dev_net(napi->dev))) 782 return NULL; 783 784 return napi; 785 } 786 787 /** 788 * netdev_napi_by_id_lock() - find a device by NAPI ID and lock it 789 * @net: the applicable net namespace 790 * @napi_id: ID of a NAPI of a target device 791 * 792 * Find a NAPI instance with @napi_id. Lock its device. 793 * The device must be in %NETREG_REGISTERED state for lookup to succeed. 794 * netdev_unlock() must be called to release it. 795 * 796 * Return: pointer to NAPI, its device with lock held, NULL if not found. 797 */ 798 struct napi_struct * 799 netdev_napi_by_id_lock(struct net *net, unsigned int napi_id) 800 { 801 struct napi_struct *napi; 802 struct net_device *dev; 803 804 rcu_read_lock(); 805 napi = netdev_napi_by_id(net, napi_id); 806 if (!napi || READ_ONCE(napi->dev->reg_state) != NETREG_REGISTERED) { 807 rcu_read_unlock(); 808 return NULL; 809 } 810 811 dev = napi->dev; 812 dev_hold(dev); 813 rcu_read_unlock(); 814 815 dev = __netdev_put_lock(dev); 816 if (!dev) 817 return NULL; 818 819 rcu_read_lock(); 820 napi = netdev_napi_by_id(net, napi_id); 821 if (napi && napi->dev != dev) 822 napi = NULL; 823 rcu_read_unlock(); 824 825 if (!napi) 826 netdev_unlock(dev); 827 return napi; 828 } 829 830 /** 831 * __dev_get_by_name - find a device by its name 832 * @net: the applicable net namespace 833 * @name: name to find 834 * 835 * Find an interface by name. Must be called under RTNL semaphore. 836 * If the name is found a pointer to the device is returned. 837 * If the name is not found then %NULL is returned. The 838 * reference counters are not incremented so the caller must be 839 * careful with locks. 840 */ 841 842 struct net_device *__dev_get_by_name(struct net *net, const char *name) 843 { 844 struct netdev_name_node *node_name; 845 846 node_name = netdev_name_node_lookup(net, name); 847 return node_name ? node_name->dev : NULL; 848 } 849 EXPORT_SYMBOL(__dev_get_by_name); 850 851 /** 852 * dev_get_by_name_rcu - find a device by its name 853 * @net: the applicable net namespace 854 * @name: name to find 855 * 856 * Find an interface by name. 857 * If the name is found a pointer to the device is returned. 858 * If the name is not found then %NULL is returned. 859 * The reference counters are not incremented so the caller must be 860 * careful with locks. The caller must hold RCU lock. 861 */ 862 863 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 864 { 865 struct netdev_name_node *node_name; 866 867 node_name = netdev_name_node_lookup_rcu(net, name); 868 return node_name ? node_name->dev : NULL; 869 } 870 EXPORT_SYMBOL(dev_get_by_name_rcu); 871 872 /* Deprecated for new users, call netdev_get_by_name() instead */ 873 struct net_device *dev_get_by_name(struct net *net, const char *name) 874 { 875 struct net_device *dev; 876 877 rcu_read_lock(); 878 dev = dev_get_by_name_rcu(net, name); 879 dev_hold(dev); 880 rcu_read_unlock(); 881 return dev; 882 } 883 EXPORT_SYMBOL(dev_get_by_name); 884 885 /** 886 * netdev_get_by_name() - find a device by its name 887 * @net: the applicable net namespace 888 * @name: name to find 889 * @tracker: tracking object for the acquired reference 890 * @gfp: allocation flags for the tracker 891 * 892 * Find an interface by name. This can be called from any 893 * context and does its own locking. The returned handle has 894 * the usage count incremented and the caller must use netdev_put() to 895 * release it when it is no longer needed. %NULL is returned if no 896 * matching device is found. 897 */ 898 struct net_device *netdev_get_by_name(struct net *net, const char *name, 899 netdevice_tracker *tracker, gfp_t gfp) 900 { 901 struct net_device *dev; 902 903 dev = dev_get_by_name(net, name); 904 if (dev) 905 netdev_tracker_alloc(dev, tracker, gfp); 906 return dev; 907 } 908 EXPORT_SYMBOL(netdev_get_by_name); 909 910 /** 911 * __dev_get_by_index - find a device by its ifindex 912 * @net: the applicable net namespace 913 * @ifindex: index of device 914 * 915 * Search for an interface by index. Returns %NULL if the device 916 * is not found or a pointer to the device. The device has not 917 * had its reference counter increased so the caller must be careful 918 * about locking. The caller must hold the RTNL semaphore. 919 */ 920 921 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 922 { 923 struct net_device *dev; 924 struct hlist_head *head = dev_index_hash(net, ifindex); 925 926 hlist_for_each_entry(dev, head, index_hlist) 927 if (dev->ifindex == ifindex) 928 return dev; 929 930 return NULL; 931 } 932 EXPORT_SYMBOL(__dev_get_by_index); 933 934 /** 935 * dev_get_by_index_rcu - find a device by its ifindex 936 * @net: the applicable net namespace 937 * @ifindex: index of device 938 * 939 * Search for an interface by index. Returns %NULL if the device 940 * is not found or a pointer to the device. The device has not 941 * had its reference counter increased so the caller must be careful 942 * about locking. The caller must hold RCU lock. 943 */ 944 945 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 946 { 947 struct net_device *dev; 948 struct hlist_head *head = dev_index_hash(net, ifindex); 949 950 hlist_for_each_entry_rcu(dev, head, index_hlist) 951 if (dev->ifindex == ifindex) 952 return dev; 953 954 return NULL; 955 } 956 EXPORT_SYMBOL(dev_get_by_index_rcu); 957 958 /* Deprecated for new users, call netdev_get_by_index() instead */ 959 struct net_device *dev_get_by_index(struct net *net, int ifindex) 960 { 961 struct net_device *dev; 962 963 rcu_read_lock(); 964 dev = dev_get_by_index_rcu(net, ifindex); 965 dev_hold(dev); 966 rcu_read_unlock(); 967 return dev; 968 } 969 EXPORT_SYMBOL(dev_get_by_index); 970 971 /** 972 * netdev_get_by_index() - find a device by its ifindex 973 * @net: the applicable net namespace 974 * @ifindex: index of device 975 * @tracker: tracking object for the acquired reference 976 * @gfp: allocation flags for the tracker 977 * 978 * Search for an interface by index. Returns NULL if the device 979 * is not found or a pointer to the device. The device returned has 980 * had a reference added and the pointer is safe until the user calls 981 * netdev_put() to indicate they have finished with it. 982 */ 983 struct net_device *netdev_get_by_index(struct net *net, int ifindex, 984 netdevice_tracker *tracker, gfp_t gfp) 985 { 986 struct net_device *dev; 987 988 dev = dev_get_by_index(net, ifindex); 989 if (dev) 990 netdev_tracker_alloc(dev, tracker, gfp); 991 return dev; 992 } 993 EXPORT_SYMBOL(netdev_get_by_index); 994 995 /** 996 * dev_get_by_napi_id - find a device by napi_id 997 * @napi_id: ID of the NAPI struct 998 * 999 * Search for an interface by NAPI ID. Returns %NULL if the device 1000 * is not found or a pointer to the device. The device has not had 1001 * its reference counter increased so the caller must be careful 1002 * about locking. The caller must hold RCU lock. 1003 */ 1004 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 1005 { 1006 struct napi_struct *napi; 1007 1008 WARN_ON_ONCE(!rcu_read_lock_held()); 1009 1010 if (napi_id < MIN_NAPI_ID) 1011 return NULL; 1012 1013 napi = napi_by_id(napi_id); 1014 1015 return napi ? napi->dev : NULL; 1016 } 1017 1018 /* Release the held reference on the net_device, and if the net_device 1019 * is still registered try to lock the instance lock. If device is being 1020 * unregistered NULL will be returned (but the reference has been released, 1021 * either way!) 1022 * 1023 * This helper is intended for locking net_device after it has been looked up 1024 * using a lockless lookup helper. Lock prevents the instance from going away. 1025 */ 1026 struct net_device *__netdev_put_lock(struct net_device *dev) 1027 { 1028 netdev_lock(dev); 1029 if (dev->reg_state > NETREG_REGISTERED) { 1030 netdev_unlock(dev); 1031 dev_put(dev); 1032 return NULL; 1033 } 1034 dev_put(dev); 1035 return dev; 1036 } 1037 1038 /** 1039 * netdev_get_by_index_lock() - find a device by its ifindex 1040 * @net: the applicable net namespace 1041 * @ifindex: index of device 1042 * 1043 * Search for an interface by index. If a valid device 1044 * with @ifindex is found it will be returned with netdev->lock held. 1045 * netdev_unlock() must be called to release it. 1046 * 1047 * Return: pointer to a device with lock held, NULL if not found. 1048 */ 1049 struct net_device *netdev_get_by_index_lock(struct net *net, int ifindex) 1050 { 1051 struct net_device *dev; 1052 1053 dev = dev_get_by_index(net, ifindex); 1054 if (!dev) 1055 return NULL; 1056 1057 return __netdev_put_lock(dev); 1058 } 1059 1060 struct net_device * 1061 netdev_xa_find_lock(struct net *net, struct net_device *dev, 1062 unsigned long *index) 1063 { 1064 if (dev) 1065 netdev_unlock(dev); 1066 1067 do { 1068 rcu_read_lock(); 1069 dev = xa_find(&net->dev_by_index, index, ULONG_MAX, XA_PRESENT); 1070 if (!dev) { 1071 rcu_read_unlock(); 1072 return NULL; 1073 } 1074 dev_hold(dev); 1075 rcu_read_unlock(); 1076 1077 dev = __netdev_put_lock(dev); 1078 if (dev) 1079 return dev; 1080 1081 (*index)++; 1082 } while (true); 1083 } 1084 1085 static DEFINE_SEQLOCK(netdev_rename_lock); 1086 1087 void netdev_copy_name(struct net_device *dev, char *name) 1088 { 1089 unsigned int seq; 1090 1091 do { 1092 seq = read_seqbegin(&netdev_rename_lock); 1093 strscpy(name, dev->name, IFNAMSIZ); 1094 } while (read_seqretry(&netdev_rename_lock, seq)); 1095 } 1096 1097 /** 1098 * netdev_get_name - get a netdevice name, knowing its ifindex. 1099 * @net: network namespace 1100 * @name: a pointer to the buffer where the name will be stored. 1101 * @ifindex: the ifindex of the interface to get the name from. 1102 */ 1103 int netdev_get_name(struct net *net, char *name, int ifindex) 1104 { 1105 struct net_device *dev; 1106 int ret; 1107 1108 rcu_read_lock(); 1109 1110 dev = dev_get_by_index_rcu(net, ifindex); 1111 if (!dev) { 1112 ret = -ENODEV; 1113 goto out; 1114 } 1115 1116 netdev_copy_name(dev, name); 1117 1118 ret = 0; 1119 out: 1120 rcu_read_unlock(); 1121 return ret; 1122 } 1123 1124 static bool dev_addr_cmp(struct net_device *dev, unsigned short type, 1125 const char *ha) 1126 { 1127 return dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len); 1128 } 1129 1130 /** 1131 * dev_getbyhwaddr_rcu - find a device by its hardware address 1132 * @net: the applicable net namespace 1133 * @type: media type of device 1134 * @ha: hardware address 1135 * 1136 * Search for an interface by MAC address. Returns NULL if the device 1137 * is not found or a pointer to the device. 1138 * The caller must hold RCU. 1139 * The returned device has not had its ref count increased 1140 * and the caller must therefore be careful about locking 1141 * 1142 */ 1143 1144 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 1145 const char *ha) 1146 { 1147 struct net_device *dev; 1148 1149 for_each_netdev_rcu(net, dev) 1150 if (dev_addr_cmp(dev, type, ha)) 1151 return dev; 1152 1153 return NULL; 1154 } 1155 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 1156 1157 /** 1158 * dev_getbyhwaddr() - find a device by its hardware address 1159 * @net: the applicable net namespace 1160 * @type: media type of device 1161 * @ha: hardware address 1162 * 1163 * Similar to dev_getbyhwaddr_rcu(), but the owner needs to hold 1164 * rtnl_lock. 1165 * 1166 * Context: rtnl_lock() must be held. 1167 * Return: pointer to the net_device, or NULL if not found 1168 */ 1169 struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type, 1170 const char *ha) 1171 { 1172 struct net_device *dev; 1173 1174 ASSERT_RTNL(); 1175 for_each_netdev(net, dev) 1176 if (dev_addr_cmp(dev, type, ha)) 1177 return dev; 1178 1179 return NULL; 1180 } 1181 EXPORT_SYMBOL(dev_getbyhwaddr); 1182 1183 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 1184 { 1185 struct net_device *dev, *ret = NULL; 1186 1187 rcu_read_lock(); 1188 for_each_netdev_rcu(net, dev) 1189 if (dev->type == type) { 1190 dev_hold(dev); 1191 ret = dev; 1192 break; 1193 } 1194 rcu_read_unlock(); 1195 return ret; 1196 } 1197 EXPORT_SYMBOL(dev_getfirstbyhwtype); 1198 1199 /** 1200 * __dev_get_by_flags - find any device with given flags 1201 * @net: the applicable net namespace 1202 * @if_flags: IFF_* values 1203 * @mask: bitmask of bits in if_flags to check 1204 * 1205 * Search for any interface with the given flags. Returns NULL if a device 1206 * is not found or a pointer to the device. Must be called inside 1207 * rtnl_lock(), and result refcount is unchanged. 1208 */ 1209 1210 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 1211 unsigned short mask) 1212 { 1213 struct net_device *dev, *ret; 1214 1215 ASSERT_RTNL(); 1216 1217 ret = NULL; 1218 for_each_netdev(net, dev) { 1219 if (((dev->flags ^ if_flags) & mask) == 0) { 1220 ret = dev; 1221 break; 1222 } 1223 } 1224 return ret; 1225 } 1226 EXPORT_SYMBOL(__dev_get_by_flags); 1227 1228 /** 1229 * dev_valid_name - check if name is okay for network device 1230 * @name: name string 1231 * 1232 * Network device names need to be valid file names to 1233 * allow sysfs to work. We also disallow any kind of 1234 * whitespace. 1235 */ 1236 bool dev_valid_name(const char *name) 1237 { 1238 if (*name == '\0') 1239 return false; 1240 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1241 return false; 1242 if (!strcmp(name, ".") || !strcmp(name, "..")) 1243 return false; 1244 1245 while (*name) { 1246 if (*name == '/' || *name == ':' || isspace(*name)) 1247 return false; 1248 name++; 1249 } 1250 return true; 1251 } 1252 EXPORT_SYMBOL(dev_valid_name); 1253 1254 /** 1255 * __dev_alloc_name - allocate a name for a device 1256 * @net: network namespace to allocate the device name in 1257 * @name: name format string 1258 * @res: result name string 1259 * 1260 * Passed a format string - eg "lt%d" it will try and find a suitable 1261 * id. It scans list of devices to build up a free map, then chooses 1262 * the first empty slot. The caller must hold the dev_base or rtnl lock 1263 * while allocating the name and adding the device in order to avoid 1264 * duplicates. 1265 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1266 * Returns the number of the unit assigned or a negative errno code. 1267 */ 1268 1269 static int __dev_alloc_name(struct net *net, const char *name, char *res) 1270 { 1271 int i = 0; 1272 const char *p; 1273 const int max_netdevices = 8*PAGE_SIZE; 1274 unsigned long *inuse; 1275 struct net_device *d; 1276 char buf[IFNAMSIZ]; 1277 1278 /* Verify the string as this thing may have come from the user. 1279 * There must be one "%d" and no other "%" characters. 1280 */ 1281 p = strchr(name, '%'); 1282 if (!p || p[1] != 'd' || strchr(p + 2, '%')) 1283 return -EINVAL; 1284 1285 /* Use one page as a bit array of possible slots */ 1286 inuse = bitmap_zalloc(max_netdevices, GFP_ATOMIC); 1287 if (!inuse) 1288 return -ENOMEM; 1289 1290 for_each_netdev(net, d) { 1291 struct netdev_name_node *name_node; 1292 1293 netdev_for_each_altname(d, name_node) { 1294 if (!sscanf(name_node->name, name, &i)) 1295 continue; 1296 if (i < 0 || i >= max_netdevices) 1297 continue; 1298 1299 /* avoid cases where sscanf is not exact inverse of printf */ 1300 snprintf(buf, IFNAMSIZ, name, i); 1301 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1302 __set_bit(i, inuse); 1303 } 1304 if (!sscanf(d->name, name, &i)) 1305 continue; 1306 if (i < 0 || i >= max_netdevices) 1307 continue; 1308 1309 /* avoid cases where sscanf is not exact inverse of printf */ 1310 snprintf(buf, IFNAMSIZ, name, i); 1311 if (!strncmp(buf, d->name, IFNAMSIZ)) 1312 __set_bit(i, inuse); 1313 } 1314 1315 i = find_first_zero_bit(inuse, max_netdevices); 1316 bitmap_free(inuse); 1317 if (i == max_netdevices) 1318 return -ENFILE; 1319 1320 /* 'res' and 'name' could overlap, use 'buf' as an intermediate buffer */ 1321 strscpy(buf, name, IFNAMSIZ); 1322 snprintf(res, IFNAMSIZ, buf, i); 1323 return i; 1324 } 1325 1326 /* Returns negative errno or allocated unit id (see __dev_alloc_name()) */ 1327 static int dev_prep_valid_name(struct net *net, struct net_device *dev, 1328 const char *want_name, char *out_name, 1329 int dup_errno) 1330 { 1331 if (!dev_valid_name(want_name)) 1332 return -EINVAL; 1333 1334 if (strchr(want_name, '%')) 1335 return __dev_alloc_name(net, want_name, out_name); 1336 1337 if (netdev_name_in_use(net, want_name)) 1338 return -dup_errno; 1339 if (out_name != want_name) 1340 strscpy(out_name, want_name, IFNAMSIZ); 1341 return 0; 1342 } 1343 1344 /** 1345 * dev_alloc_name - allocate a name for a device 1346 * @dev: device 1347 * @name: name format string 1348 * 1349 * Passed a format string - eg "lt%d" it will try and find a suitable 1350 * id. It scans list of devices to build up a free map, then chooses 1351 * the first empty slot. The caller must hold the dev_base or rtnl lock 1352 * while allocating the name and adding the device in order to avoid 1353 * duplicates. 1354 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1355 * Returns the number of the unit assigned or a negative errno code. 1356 */ 1357 1358 int dev_alloc_name(struct net_device *dev, const char *name) 1359 { 1360 return dev_prep_valid_name(dev_net(dev), dev, name, dev->name, ENFILE); 1361 } 1362 EXPORT_SYMBOL(dev_alloc_name); 1363 1364 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1365 const char *name) 1366 { 1367 int ret; 1368 1369 ret = dev_prep_valid_name(net, dev, name, dev->name, EEXIST); 1370 return ret < 0 ? ret : 0; 1371 } 1372 1373 /** 1374 * dev_change_name - change name of a device 1375 * @dev: device 1376 * @newname: name (or format string) must be at least IFNAMSIZ 1377 * 1378 * Change name of a device, can pass format strings "eth%d". 1379 * for wildcarding. 1380 */ 1381 int dev_change_name(struct net_device *dev, const char *newname) 1382 { 1383 struct net *net = dev_net(dev); 1384 unsigned char old_assign_type; 1385 char oldname[IFNAMSIZ]; 1386 int err = 0; 1387 int ret; 1388 1389 ASSERT_RTNL_NET(net); 1390 1391 if (!strncmp(newname, dev->name, IFNAMSIZ)) 1392 return 0; 1393 1394 memcpy(oldname, dev->name, IFNAMSIZ); 1395 1396 write_seqlock_bh(&netdev_rename_lock); 1397 err = dev_get_valid_name(net, dev, newname); 1398 write_sequnlock_bh(&netdev_rename_lock); 1399 1400 if (err < 0) 1401 return err; 1402 1403 if (oldname[0] && !strchr(oldname, '%')) 1404 netdev_info(dev, "renamed from %s%s\n", oldname, 1405 dev->flags & IFF_UP ? " (while UP)" : ""); 1406 1407 old_assign_type = dev->name_assign_type; 1408 WRITE_ONCE(dev->name_assign_type, NET_NAME_RENAMED); 1409 1410 rollback: 1411 ret = device_rename(&dev->dev, dev->name); 1412 if (ret) { 1413 write_seqlock_bh(&netdev_rename_lock); 1414 memcpy(dev->name, oldname, IFNAMSIZ); 1415 write_sequnlock_bh(&netdev_rename_lock); 1416 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1417 return ret; 1418 } 1419 1420 netdev_adjacent_rename_links(dev, oldname); 1421 1422 netdev_name_node_del(dev->name_node); 1423 1424 synchronize_net(); 1425 1426 netdev_name_node_add(net, dev->name_node); 1427 1428 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1429 ret = notifier_to_errno(ret); 1430 1431 if (ret) { 1432 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1433 if (err >= 0) { 1434 err = ret; 1435 write_seqlock_bh(&netdev_rename_lock); 1436 memcpy(dev->name, oldname, IFNAMSIZ); 1437 write_sequnlock_bh(&netdev_rename_lock); 1438 memcpy(oldname, newname, IFNAMSIZ); 1439 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1440 old_assign_type = NET_NAME_RENAMED; 1441 goto rollback; 1442 } else { 1443 netdev_err(dev, "name change rollback failed: %d\n", 1444 ret); 1445 } 1446 } 1447 1448 return err; 1449 } 1450 1451 /** 1452 * dev_set_alias - change ifalias of a device 1453 * @dev: device 1454 * @alias: name up to IFALIASZ 1455 * @len: limit of bytes to copy from info 1456 * 1457 * Set ifalias for a device, 1458 */ 1459 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1460 { 1461 struct dev_ifalias *new_alias = NULL; 1462 1463 if (len >= IFALIASZ) 1464 return -EINVAL; 1465 1466 if (len) { 1467 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1468 if (!new_alias) 1469 return -ENOMEM; 1470 1471 memcpy(new_alias->ifalias, alias, len); 1472 new_alias->ifalias[len] = 0; 1473 } 1474 1475 mutex_lock(&ifalias_mutex); 1476 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1477 mutex_is_locked(&ifalias_mutex)); 1478 mutex_unlock(&ifalias_mutex); 1479 1480 if (new_alias) 1481 kfree_rcu(new_alias, rcuhead); 1482 1483 return len; 1484 } 1485 EXPORT_SYMBOL(dev_set_alias); 1486 1487 /** 1488 * dev_get_alias - get ifalias of a device 1489 * @dev: device 1490 * @name: buffer to store name of ifalias 1491 * @len: size of buffer 1492 * 1493 * get ifalias for a device. Caller must make sure dev cannot go 1494 * away, e.g. rcu read lock or own a reference count to device. 1495 */ 1496 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1497 { 1498 const struct dev_ifalias *alias; 1499 int ret = 0; 1500 1501 rcu_read_lock(); 1502 alias = rcu_dereference(dev->ifalias); 1503 if (alias) 1504 ret = snprintf(name, len, "%s", alias->ifalias); 1505 rcu_read_unlock(); 1506 1507 return ret; 1508 } 1509 1510 /** 1511 * netdev_features_change - device changes features 1512 * @dev: device to cause notification 1513 * 1514 * Called to indicate a device has changed features. 1515 */ 1516 void netdev_features_change(struct net_device *dev) 1517 { 1518 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1519 } 1520 EXPORT_SYMBOL(netdev_features_change); 1521 1522 /** 1523 * netdev_state_change - device changes state 1524 * @dev: device to cause notification 1525 * 1526 * Called to indicate a device has changed state. This function calls 1527 * the notifier chains for netdev_chain and sends a NEWLINK message 1528 * to the routing socket. 1529 */ 1530 void netdev_state_change(struct net_device *dev) 1531 { 1532 if (dev->flags & IFF_UP) { 1533 struct netdev_notifier_change_info change_info = { 1534 .info.dev = dev, 1535 }; 1536 1537 call_netdevice_notifiers_info(NETDEV_CHANGE, 1538 &change_info.info); 1539 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1540 } 1541 } 1542 EXPORT_SYMBOL(netdev_state_change); 1543 1544 /** 1545 * __netdev_notify_peers - notify network peers about existence of @dev, 1546 * to be called when rtnl lock is already held. 1547 * @dev: network device 1548 * 1549 * Generate traffic such that interested network peers are aware of 1550 * @dev, such as by generating a gratuitous ARP. This may be used when 1551 * a device wants to inform the rest of the network about some sort of 1552 * reconfiguration such as a failover event or virtual machine 1553 * migration. 1554 */ 1555 void __netdev_notify_peers(struct net_device *dev) 1556 { 1557 ASSERT_RTNL(); 1558 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1559 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1560 } 1561 EXPORT_SYMBOL(__netdev_notify_peers); 1562 1563 /** 1564 * netdev_notify_peers - notify network peers about existence of @dev 1565 * @dev: network device 1566 * 1567 * Generate traffic such that interested network peers are aware of 1568 * @dev, such as by generating a gratuitous ARP. This may be used when 1569 * a device wants to inform the rest of the network about some sort of 1570 * reconfiguration such as a failover event or virtual machine 1571 * migration. 1572 */ 1573 void netdev_notify_peers(struct net_device *dev) 1574 { 1575 rtnl_lock(); 1576 __netdev_notify_peers(dev); 1577 rtnl_unlock(); 1578 } 1579 EXPORT_SYMBOL(netdev_notify_peers); 1580 1581 static int napi_threaded_poll(void *data); 1582 1583 static int napi_kthread_create(struct napi_struct *n) 1584 { 1585 int err = 0; 1586 1587 /* Create and wake up the kthread once to put it in 1588 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1589 * warning and work with loadavg. 1590 */ 1591 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1592 n->dev->name, n->napi_id); 1593 if (IS_ERR(n->thread)) { 1594 err = PTR_ERR(n->thread); 1595 pr_err("kthread_run failed with err %d\n", err); 1596 n->thread = NULL; 1597 } 1598 1599 return err; 1600 } 1601 1602 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1603 { 1604 const struct net_device_ops *ops = dev->netdev_ops; 1605 int ret; 1606 1607 ASSERT_RTNL(); 1608 dev_addr_check(dev); 1609 1610 if (!netif_device_present(dev)) { 1611 /* may be detached because parent is runtime-suspended */ 1612 if (dev->dev.parent) 1613 pm_runtime_resume(dev->dev.parent); 1614 if (!netif_device_present(dev)) 1615 return -ENODEV; 1616 } 1617 1618 /* Block netpoll from trying to do any rx path servicing. 1619 * If we don't do this there is a chance ndo_poll_controller 1620 * or ndo_poll may be running while we open the device 1621 */ 1622 netpoll_poll_disable(dev); 1623 1624 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1625 ret = notifier_to_errno(ret); 1626 if (ret) 1627 return ret; 1628 1629 set_bit(__LINK_STATE_START, &dev->state); 1630 1631 if (ops->ndo_validate_addr) 1632 ret = ops->ndo_validate_addr(dev); 1633 1634 if (!ret && ops->ndo_open) 1635 ret = ops->ndo_open(dev); 1636 1637 netpoll_poll_enable(dev); 1638 1639 if (ret) 1640 clear_bit(__LINK_STATE_START, &dev->state); 1641 else { 1642 netif_set_up(dev, true); 1643 dev_set_rx_mode(dev); 1644 dev_activate(dev); 1645 add_device_randomness(dev->dev_addr, dev->addr_len); 1646 } 1647 1648 return ret; 1649 } 1650 1651 /** 1652 * dev_open - prepare an interface for use. 1653 * @dev: device to open 1654 * @extack: netlink extended ack 1655 * 1656 * Takes a device from down to up state. The device's private open 1657 * function is invoked and then the multicast lists are loaded. Finally 1658 * the device is moved into the up state and a %NETDEV_UP message is 1659 * sent to the netdev notifier chain. 1660 * 1661 * Calling this function on an active interface is a nop. On a failure 1662 * a negative errno code is returned. 1663 */ 1664 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1665 { 1666 int ret; 1667 1668 if (dev->flags & IFF_UP) 1669 return 0; 1670 1671 ret = __dev_open(dev, extack); 1672 if (ret < 0) 1673 return ret; 1674 1675 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1676 call_netdevice_notifiers(NETDEV_UP, dev); 1677 1678 return ret; 1679 } 1680 EXPORT_SYMBOL(dev_open); 1681 1682 static void __dev_close_many(struct list_head *head) 1683 { 1684 struct net_device *dev; 1685 1686 ASSERT_RTNL(); 1687 might_sleep(); 1688 1689 list_for_each_entry(dev, head, close_list) { 1690 /* Temporarily disable netpoll until the interface is down */ 1691 netpoll_poll_disable(dev); 1692 1693 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1694 1695 clear_bit(__LINK_STATE_START, &dev->state); 1696 1697 /* Synchronize to scheduled poll. We cannot touch poll list, it 1698 * can be even on different cpu. So just clear netif_running(). 1699 * 1700 * dev->stop() will invoke napi_disable() on all of it's 1701 * napi_struct instances on this device. 1702 */ 1703 smp_mb__after_atomic(); /* Commit netif_running(). */ 1704 } 1705 1706 dev_deactivate_many(head); 1707 1708 list_for_each_entry(dev, head, close_list) { 1709 const struct net_device_ops *ops = dev->netdev_ops; 1710 1711 /* 1712 * Call the device specific close. This cannot fail. 1713 * Only if device is UP 1714 * 1715 * We allow it to be called even after a DETACH hot-plug 1716 * event. 1717 */ 1718 if (ops->ndo_stop) 1719 ops->ndo_stop(dev); 1720 1721 netif_set_up(dev, false); 1722 netpoll_poll_enable(dev); 1723 } 1724 } 1725 1726 static void __dev_close(struct net_device *dev) 1727 { 1728 LIST_HEAD(single); 1729 1730 list_add(&dev->close_list, &single); 1731 __dev_close_many(&single); 1732 list_del(&single); 1733 } 1734 1735 void dev_close_many(struct list_head *head, bool unlink) 1736 { 1737 struct net_device *dev, *tmp; 1738 1739 /* Remove the devices that don't need to be closed */ 1740 list_for_each_entry_safe(dev, tmp, head, close_list) 1741 if (!(dev->flags & IFF_UP)) 1742 list_del_init(&dev->close_list); 1743 1744 __dev_close_many(head); 1745 1746 list_for_each_entry_safe(dev, tmp, head, close_list) { 1747 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1748 call_netdevice_notifiers(NETDEV_DOWN, dev); 1749 if (unlink) 1750 list_del_init(&dev->close_list); 1751 } 1752 } 1753 EXPORT_SYMBOL(dev_close_many); 1754 1755 /** 1756 * dev_close - shutdown an interface. 1757 * @dev: device to shutdown 1758 * 1759 * This function moves an active device into down state. A 1760 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1761 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1762 * chain. 1763 */ 1764 void dev_close(struct net_device *dev) 1765 { 1766 if (dev->flags & IFF_UP) { 1767 LIST_HEAD(single); 1768 1769 list_add(&dev->close_list, &single); 1770 dev_close_many(&single, true); 1771 list_del(&single); 1772 } 1773 } 1774 EXPORT_SYMBOL(dev_close); 1775 1776 1777 /** 1778 * dev_disable_lro - disable Large Receive Offload on a device 1779 * @dev: device 1780 * 1781 * Disable Large Receive Offload (LRO) on a net device. Must be 1782 * called under RTNL. This is needed if received packets may be 1783 * forwarded to another interface. 1784 */ 1785 void dev_disable_lro(struct net_device *dev) 1786 { 1787 struct net_device *lower_dev; 1788 struct list_head *iter; 1789 1790 dev->wanted_features &= ~NETIF_F_LRO; 1791 netdev_update_features(dev); 1792 1793 if (unlikely(dev->features & NETIF_F_LRO)) 1794 netdev_WARN(dev, "failed to disable LRO!\n"); 1795 1796 netdev_for_each_lower_dev(dev, lower_dev, iter) 1797 dev_disable_lro(lower_dev); 1798 } 1799 EXPORT_SYMBOL(dev_disable_lro); 1800 1801 /** 1802 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1803 * @dev: device 1804 * 1805 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1806 * called under RTNL. This is needed if Generic XDP is installed on 1807 * the device. 1808 */ 1809 static void dev_disable_gro_hw(struct net_device *dev) 1810 { 1811 dev->wanted_features &= ~NETIF_F_GRO_HW; 1812 netdev_update_features(dev); 1813 1814 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1815 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1816 } 1817 1818 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1819 { 1820 #define N(val) \ 1821 case NETDEV_##val: \ 1822 return "NETDEV_" __stringify(val); 1823 switch (cmd) { 1824 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1825 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1826 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1827 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1828 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1829 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1830 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1831 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1832 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1833 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1834 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1835 N(XDP_FEAT_CHANGE) 1836 } 1837 #undef N 1838 return "UNKNOWN_NETDEV_EVENT"; 1839 } 1840 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1841 1842 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1843 struct net_device *dev) 1844 { 1845 struct netdev_notifier_info info = { 1846 .dev = dev, 1847 }; 1848 1849 return nb->notifier_call(nb, val, &info); 1850 } 1851 1852 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1853 struct net_device *dev) 1854 { 1855 int err; 1856 1857 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1858 err = notifier_to_errno(err); 1859 if (err) 1860 return err; 1861 1862 if (!(dev->flags & IFF_UP)) 1863 return 0; 1864 1865 call_netdevice_notifier(nb, NETDEV_UP, dev); 1866 return 0; 1867 } 1868 1869 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1870 struct net_device *dev) 1871 { 1872 if (dev->flags & IFF_UP) { 1873 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1874 dev); 1875 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1876 } 1877 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1878 } 1879 1880 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1881 struct net *net) 1882 { 1883 struct net_device *dev; 1884 int err; 1885 1886 for_each_netdev(net, dev) { 1887 err = call_netdevice_register_notifiers(nb, dev); 1888 if (err) 1889 goto rollback; 1890 } 1891 return 0; 1892 1893 rollback: 1894 for_each_netdev_continue_reverse(net, dev) 1895 call_netdevice_unregister_notifiers(nb, dev); 1896 return err; 1897 } 1898 1899 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1900 struct net *net) 1901 { 1902 struct net_device *dev; 1903 1904 for_each_netdev(net, dev) 1905 call_netdevice_unregister_notifiers(nb, dev); 1906 } 1907 1908 static int dev_boot_phase = 1; 1909 1910 /** 1911 * register_netdevice_notifier - register a network notifier block 1912 * @nb: notifier 1913 * 1914 * Register a notifier to be called when network device events occur. 1915 * The notifier passed is linked into the kernel structures and must 1916 * not be reused until it has been unregistered. A negative errno code 1917 * is returned on a failure. 1918 * 1919 * When registered all registration and up events are replayed 1920 * to the new notifier to allow device to have a race free 1921 * view of the network device list. 1922 */ 1923 1924 int register_netdevice_notifier(struct notifier_block *nb) 1925 { 1926 struct net *net; 1927 int err; 1928 1929 /* Close race with setup_net() and cleanup_net() */ 1930 down_write(&pernet_ops_rwsem); 1931 1932 /* When RTNL is removed, we need protection for netdev_chain. */ 1933 rtnl_lock(); 1934 1935 err = raw_notifier_chain_register(&netdev_chain, nb); 1936 if (err) 1937 goto unlock; 1938 if (dev_boot_phase) 1939 goto unlock; 1940 for_each_net(net) { 1941 __rtnl_net_lock(net); 1942 err = call_netdevice_register_net_notifiers(nb, net); 1943 __rtnl_net_unlock(net); 1944 if (err) 1945 goto rollback; 1946 } 1947 1948 unlock: 1949 rtnl_unlock(); 1950 up_write(&pernet_ops_rwsem); 1951 return err; 1952 1953 rollback: 1954 for_each_net_continue_reverse(net) { 1955 __rtnl_net_lock(net); 1956 call_netdevice_unregister_net_notifiers(nb, net); 1957 __rtnl_net_unlock(net); 1958 } 1959 1960 raw_notifier_chain_unregister(&netdev_chain, nb); 1961 goto unlock; 1962 } 1963 EXPORT_SYMBOL(register_netdevice_notifier); 1964 1965 /** 1966 * unregister_netdevice_notifier - unregister a network notifier block 1967 * @nb: notifier 1968 * 1969 * Unregister a notifier previously registered by 1970 * register_netdevice_notifier(). The notifier is unlinked into the 1971 * kernel structures and may then be reused. A negative errno code 1972 * is returned on a failure. 1973 * 1974 * After unregistering unregister and down device events are synthesized 1975 * for all devices on the device list to the removed notifier to remove 1976 * the need for special case cleanup code. 1977 */ 1978 1979 int unregister_netdevice_notifier(struct notifier_block *nb) 1980 { 1981 struct net *net; 1982 int err; 1983 1984 /* Close race with setup_net() and cleanup_net() */ 1985 down_write(&pernet_ops_rwsem); 1986 rtnl_lock(); 1987 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1988 if (err) 1989 goto unlock; 1990 1991 for_each_net(net) { 1992 __rtnl_net_lock(net); 1993 call_netdevice_unregister_net_notifiers(nb, net); 1994 __rtnl_net_unlock(net); 1995 } 1996 1997 unlock: 1998 rtnl_unlock(); 1999 up_write(&pernet_ops_rwsem); 2000 return err; 2001 } 2002 EXPORT_SYMBOL(unregister_netdevice_notifier); 2003 2004 static int __register_netdevice_notifier_net(struct net *net, 2005 struct notifier_block *nb, 2006 bool ignore_call_fail) 2007 { 2008 int err; 2009 2010 err = raw_notifier_chain_register(&net->netdev_chain, nb); 2011 if (err) 2012 return err; 2013 if (dev_boot_phase) 2014 return 0; 2015 2016 err = call_netdevice_register_net_notifiers(nb, net); 2017 if (err && !ignore_call_fail) 2018 goto chain_unregister; 2019 2020 return 0; 2021 2022 chain_unregister: 2023 raw_notifier_chain_unregister(&net->netdev_chain, nb); 2024 return err; 2025 } 2026 2027 static int __unregister_netdevice_notifier_net(struct net *net, 2028 struct notifier_block *nb) 2029 { 2030 int err; 2031 2032 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 2033 if (err) 2034 return err; 2035 2036 call_netdevice_unregister_net_notifiers(nb, net); 2037 return 0; 2038 } 2039 2040 /** 2041 * register_netdevice_notifier_net - register a per-netns network notifier block 2042 * @net: network namespace 2043 * @nb: notifier 2044 * 2045 * Register a notifier to be called when network device events occur. 2046 * The notifier passed is linked into the kernel structures and must 2047 * not be reused until it has been unregistered. A negative errno code 2048 * is returned on a failure. 2049 * 2050 * When registered all registration and up events are replayed 2051 * to the new notifier to allow device to have a race free 2052 * view of the network device list. 2053 */ 2054 2055 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 2056 { 2057 int err; 2058 2059 rtnl_net_lock(net); 2060 err = __register_netdevice_notifier_net(net, nb, false); 2061 rtnl_net_unlock(net); 2062 2063 return err; 2064 } 2065 EXPORT_SYMBOL(register_netdevice_notifier_net); 2066 2067 /** 2068 * unregister_netdevice_notifier_net - unregister a per-netns 2069 * network notifier block 2070 * @net: network namespace 2071 * @nb: notifier 2072 * 2073 * Unregister a notifier previously registered by 2074 * register_netdevice_notifier_net(). The notifier is unlinked from the 2075 * kernel structures and may then be reused. A negative errno code 2076 * is returned on a failure. 2077 * 2078 * After unregistering unregister and down device events are synthesized 2079 * for all devices on the device list to the removed notifier to remove 2080 * the need for special case cleanup code. 2081 */ 2082 2083 int unregister_netdevice_notifier_net(struct net *net, 2084 struct notifier_block *nb) 2085 { 2086 int err; 2087 2088 rtnl_net_lock(net); 2089 err = __unregister_netdevice_notifier_net(net, nb); 2090 rtnl_net_unlock(net); 2091 2092 return err; 2093 } 2094 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 2095 2096 static void __move_netdevice_notifier_net(struct net *src_net, 2097 struct net *dst_net, 2098 struct notifier_block *nb) 2099 { 2100 __unregister_netdevice_notifier_net(src_net, nb); 2101 __register_netdevice_notifier_net(dst_net, nb, true); 2102 } 2103 2104 static void rtnl_net_dev_lock(struct net_device *dev) 2105 { 2106 bool again; 2107 2108 do { 2109 struct net *net; 2110 2111 again = false; 2112 2113 /* netns might be being dismantled. */ 2114 rcu_read_lock(); 2115 net = dev_net_rcu(dev); 2116 net_passive_inc(net); 2117 rcu_read_unlock(); 2118 2119 rtnl_net_lock(net); 2120 2121 #ifdef CONFIG_NET_NS 2122 /* dev might have been moved to another netns. */ 2123 if (!net_eq(net, rcu_access_pointer(dev->nd_net.net))) { 2124 rtnl_net_unlock(net); 2125 net_passive_dec(net); 2126 again = true; 2127 } 2128 #endif 2129 } while (again); 2130 } 2131 2132 static void rtnl_net_dev_unlock(struct net_device *dev) 2133 { 2134 struct net *net = dev_net(dev); 2135 2136 rtnl_net_unlock(net); 2137 net_passive_dec(net); 2138 } 2139 2140 int register_netdevice_notifier_dev_net(struct net_device *dev, 2141 struct notifier_block *nb, 2142 struct netdev_net_notifier *nn) 2143 { 2144 int err; 2145 2146 rtnl_net_dev_lock(dev); 2147 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 2148 if (!err) { 2149 nn->nb = nb; 2150 list_add(&nn->list, &dev->net_notifier_list); 2151 } 2152 rtnl_net_dev_unlock(dev); 2153 2154 return err; 2155 } 2156 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 2157 2158 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 2159 struct notifier_block *nb, 2160 struct netdev_net_notifier *nn) 2161 { 2162 int err; 2163 2164 rtnl_net_dev_lock(dev); 2165 list_del(&nn->list); 2166 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 2167 rtnl_net_dev_unlock(dev); 2168 2169 return err; 2170 } 2171 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 2172 2173 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 2174 struct net *net) 2175 { 2176 struct netdev_net_notifier *nn; 2177 2178 list_for_each_entry(nn, &dev->net_notifier_list, list) 2179 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 2180 } 2181 2182 /** 2183 * call_netdevice_notifiers_info - call all network notifier blocks 2184 * @val: value passed unmodified to notifier function 2185 * @info: notifier information data 2186 * 2187 * Call all network notifier blocks. Parameters and return value 2188 * are as for raw_notifier_call_chain(). 2189 */ 2190 2191 int call_netdevice_notifiers_info(unsigned long val, 2192 struct netdev_notifier_info *info) 2193 { 2194 struct net *net = dev_net(info->dev); 2195 int ret; 2196 2197 ASSERT_RTNL(); 2198 2199 /* Run per-netns notifier block chain first, then run the global one. 2200 * Hopefully, one day, the global one is going to be removed after 2201 * all notifier block registrators get converted to be per-netns. 2202 */ 2203 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 2204 if (ret & NOTIFY_STOP_MASK) 2205 return ret; 2206 return raw_notifier_call_chain(&netdev_chain, val, info); 2207 } 2208 2209 /** 2210 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 2211 * for and rollback on error 2212 * @val_up: value passed unmodified to notifier function 2213 * @val_down: value passed unmodified to the notifier function when 2214 * recovering from an error on @val_up 2215 * @info: notifier information data 2216 * 2217 * Call all per-netns network notifier blocks, but not notifier blocks on 2218 * the global notifier chain. Parameters and return value are as for 2219 * raw_notifier_call_chain_robust(). 2220 */ 2221 2222 static int 2223 call_netdevice_notifiers_info_robust(unsigned long val_up, 2224 unsigned long val_down, 2225 struct netdev_notifier_info *info) 2226 { 2227 struct net *net = dev_net(info->dev); 2228 2229 ASSERT_RTNL(); 2230 2231 return raw_notifier_call_chain_robust(&net->netdev_chain, 2232 val_up, val_down, info); 2233 } 2234 2235 static int call_netdevice_notifiers_extack(unsigned long val, 2236 struct net_device *dev, 2237 struct netlink_ext_ack *extack) 2238 { 2239 struct netdev_notifier_info info = { 2240 .dev = dev, 2241 .extack = extack, 2242 }; 2243 2244 return call_netdevice_notifiers_info(val, &info); 2245 } 2246 2247 /** 2248 * call_netdevice_notifiers - call all network notifier blocks 2249 * @val: value passed unmodified to notifier function 2250 * @dev: net_device pointer passed unmodified to notifier function 2251 * 2252 * Call all network notifier blocks. Parameters and return value 2253 * are as for raw_notifier_call_chain(). 2254 */ 2255 2256 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 2257 { 2258 return call_netdevice_notifiers_extack(val, dev, NULL); 2259 } 2260 EXPORT_SYMBOL(call_netdevice_notifiers); 2261 2262 /** 2263 * call_netdevice_notifiers_mtu - call all network notifier blocks 2264 * @val: value passed unmodified to notifier function 2265 * @dev: net_device pointer passed unmodified to notifier function 2266 * @arg: additional u32 argument passed to the notifier function 2267 * 2268 * Call all network notifier blocks. Parameters and return value 2269 * are as for raw_notifier_call_chain(). 2270 */ 2271 static int call_netdevice_notifiers_mtu(unsigned long val, 2272 struct net_device *dev, u32 arg) 2273 { 2274 struct netdev_notifier_info_ext info = { 2275 .info.dev = dev, 2276 .ext.mtu = arg, 2277 }; 2278 2279 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2280 2281 return call_netdevice_notifiers_info(val, &info.info); 2282 } 2283 2284 #ifdef CONFIG_NET_INGRESS 2285 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2286 2287 void net_inc_ingress_queue(void) 2288 { 2289 static_branch_inc(&ingress_needed_key); 2290 } 2291 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2292 2293 void net_dec_ingress_queue(void) 2294 { 2295 static_branch_dec(&ingress_needed_key); 2296 } 2297 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2298 #endif 2299 2300 #ifdef CONFIG_NET_EGRESS 2301 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2302 2303 void net_inc_egress_queue(void) 2304 { 2305 static_branch_inc(&egress_needed_key); 2306 } 2307 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2308 2309 void net_dec_egress_queue(void) 2310 { 2311 static_branch_dec(&egress_needed_key); 2312 } 2313 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2314 #endif 2315 2316 #ifdef CONFIG_NET_CLS_ACT 2317 DEFINE_STATIC_KEY_FALSE(tcf_sw_enabled_key); 2318 EXPORT_SYMBOL(tcf_sw_enabled_key); 2319 #endif 2320 2321 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2322 EXPORT_SYMBOL(netstamp_needed_key); 2323 #ifdef CONFIG_JUMP_LABEL 2324 static atomic_t netstamp_needed_deferred; 2325 static atomic_t netstamp_wanted; 2326 static void netstamp_clear(struct work_struct *work) 2327 { 2328 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2329 int wanted; 2330 2331 wanted = atomic_add_return(deferred, &netstamp_wanted); 2332 if (wanted > 0) 2333 static_branch_enable(&netstamp_needed_key); 2334 else 2335 static_branch_disable(&netstamp_needed_key); 2336 } 2337 static DECLARE_WORK(netstamp_work, netstamp_clear); 2338 #endif 2339 2340 void net_enable_timestamp(void) 2341 { 2342 #ifdef CONFIG_JUMP_LABEL 2343 int wanted = atomic_read(&netstamp_wanted); 2344 2345 while (wanted > 0) { 2346 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1)) 2347 return; 2348 } 2349 atomic_inc(&netstamp_needed_deferred); 2350 schedule_work(&netstamp_work); 2351 #else 2352 static_branch_inc(&netstamp_needed_key); 2353 #endif 2354 } 2355 EXPORT_SYMBOL(net_enable_timestamp); 2356 2357 void net_disable_timestamp(void) 2358 { 2359 #ifdef CONFIG_JUMP_LABEL 2360 int wanted = atomic_read(&netstamp_wanted); 2361 2362 while (wanted > 1) { 2363 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1)) 2364 return; 2365 } 2366 atomic_dec(&netstamp_needed_deferred); 2367 schedule_work(&netstamp_work); 2368 #else 2369 static_branch_dec(&netstamp_needed_key); 2370 #endif 2371 } 2372 EXPORT_SYMBOL(net_disable_timestamp); 2373 2374 static inline void net_timestamp_set(struct sk_buff *skb) 2375 { 2376 skb->tstamp = 0; 2377 skb->tstamp_type = SKB_CLOCK_REALTIME; 2378 if (static_branch_unlikely(&netstamp_needed_key)) 2379 skb->tstamp = ktime_get_real(); 2380 } 2381 2382 #define net_timestamp_check(COND, SKB) \ 2383 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2384 if ((COND) && !(SKB)->tstamp) \ 2385 (SKB)->tstamp = ktime_get_real(); \ 2386 } \ 2387 2388 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2389 { 2390 return __is_skb_forwardable(dev, skb, true); 2391 } 2392 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2393 2394 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2395 bool check_mtu) 2396 { 2397 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2398 2399 if (likely(!ret)) { 2400 skb->protocol = eth_type_trans(skb, dev); 2401 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2402 } 2403 2404 return ret; 2405 } 2406 2407 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2408 { 2409 return __dev_forward_skb2(dev, skb, true); 2410 } 2411 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2412 2413 /** 2414 * dev_forward_skb - loopback an skb to another netif 2415 * 2416 * @dev: destination network device 2417 * @skb: buffer to forward 2418 * 2419 * return values: 2420 * NET_RX_SUCCESS (no congestion) 2421 * NET_RX_DROP (packet was dropped, but freed) 2422 * 2423 * dev_forward_skb can be used for injecting an skb from the 2424 * start_xmit function of one device into the receive queue 2425 * of another device. 2426 * 2427 * The receiving device may be in another namespace, so 2428 * we have to clear all information in the skb that could 2429 * impact namespace isolation. 2430 */ 2431 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2432 { 2433 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2434 } 2435 EXPORT_SYMBOL_GPL(dev_forward_skb); 2436 2437 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2438 { 2439 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2440 } 2441 2442 static inline int deliver_skb(struct sk_buff *skb, 2443 struct packet_type *pt_prev, 2444 struct net_device *orig_dev) 2445 { 2446 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2447 return -ENOMEM; 2448 refcount_inc(&skb->users); 2449 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2450 } 2451 2452 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2453 struct packet_type **pt, 2454 struct net_device *orig_dev, 2455 __be16 type, 2456 struct list_head *ptype_list) 2457 { 2458 struct packet_type *ptype, *pt_prev = *pt; 2459 2460 list_for_each_entry_rcu(ptype, ptype_list, list) { 2461 if (ptype->type != type) 2462 continue; 2463 if (pt_prev) 2464 deliver_skb(skb, pt_prev, orig_dev); 2465 pt_prev = ptype; 2466 } 2467 *pt = pt_prev; 2468 } 2469 2470 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2471 { 2472 if (!ptype->af_packet_priv || !skb->sk) 2473 return false; 2474 2475 if (ptype->id_match) 2476 return ptype->id_match(ptype, skb->sk); 2477 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2478 return true; 2479 2480 return false; 2481 } 2482 2483 /** 2484 * dev_nit_active - return true if any network interface taps are in use 2485 * 2486 * @dev: network device to check for the presence of taps 2487 */ 2488 bool dev_nit_active(struct net_device *dev) 2489 { 2490 return !list_empty(&net_hotdata.ptype_all) || 2491 !list_empty(&dev->ptype_all); 2492 } 2493 EXPORT_SYMBOL_GPL(dev_nit_active); 2494 2495 /* 2496 * Support routine. Sends outgoing frames to any network 2497 * taps currently in use. 2498 */ 2499 2500 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2501 { 2502 struct list_head *ptype_list = &net_hotdata.ptype_all; 2503 struct packet_type *ptype, *pt_prev = NULL; 2504 struct sk_buff *skb2 = NULL; 2505 2506 rcu_read_lock(); 2507 again: 2508 list_for_each_entry_rcu(ptype, ptype_list, list) { 2509 if (READ_ONCE(ptype->ignore_outgoing)) 2510 continue; 2511 2512 /* Never send packets back to the socket 2513 * they originated from - MvS (miquels@drinkel.ow.org) 2514 */ 2515 if (skb_loop_sk(ptype, skb)) 2516 continue; 2517 2518 if (pt_prev) { 2519 deliver_skb(skb2, pt_prev, skb->dev); 2520 pt_prev = ptype; 2521 continue; 2522 } 2523 2524 /* need to clone skb, done only once */ 2525 skb2 = skb_clone(skb, GFP_ATOMIC); 2526 if (!skb2) 2527 goto out_unlock; 2528 2529 net_timestamp_set(skb2); 2530 2531 /* skb->nh should be correctly 2532 * set by sender, so that the second statement is 2533 * just protection against buggy protocols. 2534 */ 2535 skb_reset_mac_header(skb2); 2536 2537 if (skb_network_header(skb2) < skb2->data || 2538 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2539 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2540 ntohs(skb2->protocol), 2541 dev->name); 2542 skb_reset_network_header(skb2); 2543 } 2544 2545 skb2->transport_header = skb2->network_header; 2546 skb2->pkt_type = PACKET_OUTGOING; 2547 pt_prev = ptype; 2548 } 2549 2550 if (ptype_list == &net_hotdata.ptype_all) { 2551 ptype_list = &dev->ptype_all; 2552 goto again; 2553 } 2554 out_unlock: 2555 if (pt_prev) { 2556 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2557 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2558 else 2559 kfree_skb(skb2); 2560 } 2561 rcu_read_unlock(); 2562 } 2563 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2564 2565 /** 2566 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2567 * @dev: Network device 2568 * @txq: number of queues available 2569 * 2570 * If real_num_tx_queues is changed the tc mappings may no longer be 2571 * valid. To resolve this verify the tc mapping remains valid and if 2572 * not NULL the mapping. With no priorities mapping to this 2573 * offset/count pair it will no longer be used. In the worst case TC0 2574 * is invalid nothing can be done so disable priority mappings. If is 2575 * expected that drivers will fix this mapping if they can before 2576 * calling netif_set_real_num_tx_queues. 2577 */ 2578 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2579 { 2580 int i; 2581 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2582 2583 /* If TC0 is invalidated disable TC mapping */ 2584 if (tc->offset + tc->count > txq) { 2585 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2586 dev->num_tc = 0; 2587 return; 2588 } 2589 2590 /* Invalidated prio to tc mappings set to TC0 */ 2591 for (i = 1; i < TC_BITMASK + 1; i++) { 2592 int q = netdev_get_prio_tc_map(dev, i); 2593 2594 tc = &dev->tc_to_txq[q]; 2595 if (tc->offset + tc->count > txq) { 2596 netdev_warn(dev, "Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n", 2597 i, q); 2598 netdev_set_prio_tc_map(dev, i, 0); 2599 } 2600 } 2601 } 2602 2603 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2604 { 2605 if (dev->num_tc) { 2606 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2607 int i; 2608 2609 /* walk through the TCs and see if it falls into any of them */ 2610 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2611 if ((txq - tc->offset) < tc->count) 2612 return i; 2613 } 2614 2615 /* didn't find it, just return -1 to indicate no match */ 2616 return -1; 2617 } 2618 2619 return 0; 2620 } 2621 EXPORT_SYMBOL(netdev_txq_to_tc); 2622 2623 #ifdef CONFIG_XPS 2624 static struct static_key xps_needed __read_mostly; 2625 static struct static_key xps_rxqs_needed __read_mostly; 2626 static DEFINE_MUTEX(xps_map_mutex); 2627 #define xmap_dereference(P) \ 2628 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2629 2630 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2631 struct xps_dev_maps *old_maps, int tci, u16 index) 2632 { 2633 struct xps_map *map = NULL; 2634 int pos; 2635 2636 map = xmap_dereference(dev_maps->attr_map[tci]); 2637 if (!map) 2638 return false; 2639 2640 for (pos = map->len; pos--;) { 2641 if (map->queues[pos] != index) 2642 continue; 2643 2644 if (map->len > 1) { 2645 map->queues[pos] = map->queues[--map->len]; 2646 break; 2647 } 2648 2649 if (old_maps) 2650 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2651 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2652 kfree_rcu(map, rcu); 2653 return false; 2654 } 2655 2656 return true; 2657 } 2658 2659 static bool remove_xps_queue_cpu(struct net_device *dev, 2660 struct xps_dev_maps *dev_maps, 2661 int cpu, u16 offset, u16 count) 2662 { 2663 int num_tc = dev_maps->num_tc; 2664 bool active = false; 2665 int tci; 2666 2667 for (tci = cpu * num_tc; num_tc--; tci++) { 2668 int i, j; 2669 2670 for (i = count, j = offset; i--; j++) { 2671 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2672 break; 2673 } 2674 2675 active |= i < 0; 2676 } 2677 2678 return active; 2679 } 2680 2681 static void reset_xps_maps(struct net_device *dev, 2682 struct xps_dev_maps *dev_maps, 2683 enum xps_map_type type) 2684 { 2685 static_key_slow_dec_cpuslocked(&xps_needed); 2686 if (type == XPS_RXQS) 2687 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2688 2689 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2690 2691 kfree_rcu(dev_maps, rcu); 2692 } 2693 2694 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2695 u16 offset, u16 count) 2696 { 2697 struct xps_dev_maps *dev_maps; 2698 bool active = false; 2699 int i, j; 2700 2701 dev_maps = xmap_dereference(dev->xps_maps[type]); 2702 if (!dev_maps) 2703 return; 2704 2705 for (j = 0; j < dev_maps->nr_ids; j++) 2706 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2707 if (!active) 2708 reset_xps_maps(dev, dev_maps, type); 2709 2710 if (type == XPS_CPUS) { 2711 for (i = offset + (count - 1); count--; i--) 2712 netdev_queue_numa_node_write( 2713 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2714 } 2715 } 2716 2717 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2718 u16 count) 2719 { 2720 if (!static_key_false(&xps_needed)) 2721 return; 2722 2723 cpus_read_lock(); 2724 mutex_lock(&xps_map_mutex); 2725 2726 if (static_key_false(&xps_rxqs_needed)) 2727 clean_xps_maps(dev, XPS_RXQS, offset, count); 2728 2729 clean_xps_maps(dev, XPS_CPUS, offset, count); 2730 2731 mutex_unlock(&xps_map_mutex); 2732 cpus_read_unlock(); 2733 } 2734 2735 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2736 { 2737 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2738 } 2739 2740 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2741 u16 index, bool is_rxqs_map) 2742 { 2743 struct xps_map *new_map; 2744 int alloc_len = XPS_MIN_MAP_ALLOC; 2745 int i, pos; 2746 2747 for (pos = 0; map && pos < map->len; pos++) { 2748 if (map->queues[pos] != index) 2749 continue; 2750 return map; 2751 } 2752 2753 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2754 if (map) { 2755 if (pos < map->alloc_len) 2756 return map; 2757 2758 alloc_len = map->alloc_len * 2; 2759 } 2760 2761 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2762 * map 2763 */ 2764 if (is_rxqs_map) 2765 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2766 else 2767 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2768 cpu_to_node(attr_index)); 2769 if (!new_map) 2770 return NULL; 2771 2772 for (i = 0; i < pos; i++) 2773 new_map->queues[i] = map->queues[i]; 2774 new_map->alloc_len = alloc_len; 2775 new_map->len = pos; 2776 2777 return new_map; 2778 } 2779 2780 /* Copy xps maps at a given index */ 2781 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2782 struct xps_dev_maps *new_dev_maps, int index, 2783 int tc, bool skip_tc) 2784 { 2785 int i, tci = index * dev_maps->num_tc; 2786 struct xps_map *map; 2787 2788 /* copy maps belonging to foreign traffic classes */ 2789 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2790 if (i == tc && skip_tc) 2791 continue; 2792 2793 /* fill in the new device map from the old device map */ 2794 map = xmap_dereference(dev_maps->attr_map[tci]); 2795 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2796 } 2797 } 2798 2799 /* Must be called under cpus_read_lock */ 2800 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2801 u16 index, enum xps_map_type type) 2802 { 2803 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2804 const unsigned long *online_mask = NULL; 2805 bool active = false, copy = false; 2806 int i, j, tci, numa_node_id = -2; 2807 int maps_sz, num_tc = 1, tc = 0; 2808 struct xps_map *map, *new_map; 2809 unsigned int nr_ids; 2810 2811 WARN_ON_ONCE(index >= dev->num_tx_queues); 2812 2813 if (dev->num_tc) { 2814 /* Do not allow XPS on subordinate device directly */ 2815 num_tc = dev->num_tc; 2816 if (num_tc < 0) 2817 return -EINVAL; 2818 2819 /* If queue belongs to subordinate dev use its map */ 2820 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2821 2822 tc = netdev_txq_to_tc(dev, index); 2823 if (tc < 0) 2824 return -EINVAL; 2825 } 2826 2827 mutex_lock(&xps_map_mutex); 2828 2829 dev_maps = xmap_dereference(dev->xps_maps[type]); 2830 if (type == XPS_RXQS) { 2831 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2832 nr_ids = dev->num_rx_queues; 2833 } else { 2834 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2835 if (num_possible_cpus() > 1) 2836 online_mask = cpumask_bits(cpu_online_mask); 2837 nr_ids = nr_cpu_ids; 2838 } 2839 2840 if (maps_sz < L1_CACHE_BYTES) 2841 maps_sz = L1_CACHE_BYTES; 2842 2843 /* The old dev_maps could be larger or smaller than the one we're 2844 * setting up now, as dev->num_tc or nr_ids could have been updated in 2845 * between. We could try to be smart, but let's be safe instead and only 2846 * copy foreign traffic classes if the two map sizes match. 2847 */ 2848 if (dev_maps && 2849 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2850 copy = true; 2851 2852 /* allocate memory for queue storage */ 2853 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2854 j < nr_ids;) { 2855 if (!new_dev_maps) { 2856 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2857 if (!new_dev_maps) { 2858 mutex_unlock(&xps_map_mutex); 2859 return -ENOMEM; 2860 } 2861 2862 new_dev_maps->nr_ids = nr_ids; 2863 new_dev_maps->num_tc = num_tc; 2864 } 2865 2866 tci = j * num_tc + tc; 2867 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2868 2869 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2870 if (!map) 2871 goto error; 2872 2873 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2874 } 2875 2876 if (!new_dev_maps) 2877 goto out_no_new_maps; 2878 2879 if (!dev_maps) { 2880 /* Increment static keys at most once per type */ 2881 static_key_slow_inc_cpuslocked(&xps_needed); 2882 if (type == XPS_RXQS) 2883 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2884 } 2885 2886 for (j = 0; j < nr_ids; j++) { 2887 bool skip_tc = false; 2888 2889 tci = j * num_tc + tc; 2890 if (netif_attr_test_mask(j, mask, nr_ids) && 2891 netif_attr_test_online(j, online_mask, nr_ids)) { 2892 /* add tx-queue to CPU/rx-queue maps */ 2893 int pos = 0; 2894 2895 skip_tc = true; 2896 2897 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2898 while ((pos < map->len) && (map->queues[pos] != index)) 2899 pos++; 2900 2901 if (pos == map->len) 2902 map->queues[map->len++] = index; 2903 #ifdef CONFIG_NUMA 2904 if (type == XPS_CPUS) { 2905 if (numa_node_id == -2) 2906 numa_node_id = cpu_to_node(j); 2907 else if (numa_node_id != cpu_to_node(j)) 2908 numa_node_id = -1; 2909 } 2910 #endif 2911 } 2912 2913 if (copy) 2914 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2915 skip_tc); 2916 } 2917 2918 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2919 2920 /* Cleanup old maps */ 2921 if (!dev_maps) 2922 goto out_no_old_maps; 2923 2924 for (j = 0; j < dev_maps->nr_ids; j++) { 2925 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2926 map = xmap_dereference(dev_maps->attr_map[tci]); 2927 if (!map) 2928 continue; 2929 2930 if (copy) { 2931 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2932 if (map == new_map) 2933 continue; 2934 } 2935 2936 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2937 kfree_rcu(map, rcu); 2938 } 2939 } 2940 2941 old_dev_maps = dev_maps; 2942 2943 out_no_old_maps: 2944 dev_maps = new_dev_maps; 2945 active = true; 2946 2947 out_no_new_maps: 2948 if (type == XPS_CPUS) 2949 /* update Tx queue numa node */ 2950 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2951 (numa_node_id >= 0) ? 2952 numa_node_id : NUMA_NO_NODE); 2953 2954 if (!dev_maps) 2955 goto out_no_maps; 2956 2957 /* removes tx-queue from unused CPUs/rx-queues */ 2958 for (j = 0; j < dev_maps->nr_ids; j++) { 2959 tci = j * dev_maps->num_tc; 2960 2961 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2962 if (i == tc && 2963 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2964 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2965 continue; 2966 2967 active |= remove_xps_queue(dev_maps, 2968 copy ? old_dev_maps : NULL, 2969 tci, index); 2970 } 2971 } 2972 2973 if (old_dev_maps) 2974 kfree_rcu(old_dev_maps, rcu); 2975 2976 /* free map if not active */ 2977 if (!active) 2978 reset_xps_maps(dev, dev_maps, type); 2979 2980 out_no_maps: 2981 mutex_unlock(&xps_map_mutex); 2982 2983 return 0; 2984 error: 2985 /* remove any maps that we added */ 2986 for (j = 0; j < nr_ids; j++) { 2987 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2988 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2989 map = copy ? 2990 xmap_dereference(dev_maps->attr_map[tci]) : 2991 NULL; 2992 if (new_map && new_map != map) 2993 kfree(new_map); 2994 } 2995 } 2996 2997 mutex_unlock(&xps_map_mutex); 2998 2999 kfree(new_dev_maps); 3000 return -ENOMEM; 3001 } 3002 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 3003 3004 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 3005 u16 index) 3006 { 3007 int ret; 3008 3009 cpus_read_lock(); 3010 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 3011 cpus_read_unlock(); 3012 3013 return ret; 3014 } 3015 EXPORT_SYMBOL(netif_set_xps_queue); 3016 3017 #endif 3018 static void netdev_unbind_all_sb_channels(struct net_device *dev) 3019 { 3020 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 3021 3022 /* Unbind any subordinate channels */ 3023 while (txq-- != &dev->_tx[0]) { 3024 if (txq->sb_dev) 3025 netdev_unbind_sb_channel(dev, txq->sb_dev); 3026 } 3027 } 3028 3029 void netdev_reset_tc(struct net_device *dev) 3030 { 3031 #ifdef CONFIG_XPS 3032 netif_reset_xps_queues_gt(dev, 0); 3033 #endif 3034 netdev_unbind_all_sb_channels(dev); 3035 3036 /* Reset TC configuration of device */ 3037 dev->num_tc = 0; 3038 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 3039 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 3040 } 3041 EXPORT_SYMBOL(netdev_reset_tc); 3042 3043 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 3044 { 3045 if (tc >= dev->num_tc) 3046 return -EINVAL; 3047 3048 #ifdef CONFIG_XPS 3049 netif_reset_xps_queues(dev, offset, count); 3050 #endif 3051 dev->tc_to_txq[tc].count = count; 3052 dev->tc_to_txq[tc].offset = offset; 3053 return 0; 3054 } 3055 EXPORT_SYMBOL(netdev_set_tc_queue); 3056 3057 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 3058 { 3059 if (num_tc > TC_MAX_QUEUE) 3060 return -EINVAL; 3061 3062 #ifdef CONFIG_XPS 3063 netif_reset_xps_queues_gt(dev, 0); 3064 #endif 3065 netdev_unbind_all_sb_channels(dev); 3066 3067 dev->num_tc = num_tc; 3068 return 0; 3069 } 3070 EXPORT_SYMBOL(netdev_set_num_tc); 3071 3072 void netdev_unbind_sb_channel(struct net_device *dev, 3073 struct net_device *sb_dev) 3074 { 3075 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 3076 3077 #ifdef CONFIG_XPS 3078 netif_reset_xps_queues_gt(sb_dev, 0); 3079 #endif 3080 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 3081 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 3082 3083 while (txq-- != &dev->_tx[0]) { 3084 if (txq->sb_dev == sb_dev) 3085 txq->sb_dev = NULL; 3086 } 3087 } 3088 EXPORT_SYMBOL(netdev_unbind_sb_channel); 3089 3090 int netdev_bind_sb_channel_queue(struct net_device *dev, 3091 struct net_device *sb_dev, 3092 u8 tc, u16 count, u16 offset) 3093 { 3094 /* Make certain the sb_dev and dev are already configured */ 3095 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 3096 return -EINVAL; 3097 3098 /* We cannot hand out queues we don't have */ 3099 if ((offset + count) > dev->real_num_tx_queues) 3100 return -EINVAL; 3101 3102 /* Record the mapping */ 3103 sb_dev->tc_to_txq[tc].count = count; 3104 sb_dev->tc_to_txq[tc].offset = offset; 3105 3106 /* Provide a way for Tx queue to find the tc_to_txq map or 3107 * XPS map for itself. 3108 */ 3109 while (count--) 3110 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 3111 3112 return 0; 3113 } 3114 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 3115 3116 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 3117 { 3118 /* Do not use a multiqueue device to represent a subordinate channel */ 3119 if (netif_is_multiqueue(dev)) 3120 return -ENODEV; 3121 3122 /* We allow channels 1 - 32767 to be used for subordinate channels. 3123 * Channel 0 is meant to be "native" mode and used only to represent 3124 * the main root device. We allow writing 0 to reset the device back 3125 * to normal mode after being used as a subordinate channel. 3126 */ 3127 if (channel > S16_MAX) 3128 return -EINVAL; 3129 3130 dev->num_tc = -channel; 3131 3132 return 0; 3133 } 3134 EXPORT_SYMBOL(netdev_set_sb_channel); 3135 3136 /* 3137 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 3138 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 3139 */ 3140 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 3141 { 3142 bool disabling; 3143 int rc; 3144 3145 disabling = txq < dev->real_num_tx_queues; 3146 3147 if (txq < 1 || txq > dev->num_tx_queues) 3148 return -EINVAL; 3149 3150 if (dev->reg_state == NETREG_REGISTERED || 3151 dev->reg_state == NETREG_UNREGISTERING) { 3152 ASSERT_RTNL(); 3153 3154 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 3155 txq); 3156 if (rc) 3157 return rc; 3158 3159 if (dev->num_tc) 3160 netif_setup_tc(dev, txq); 3161 3162 net_shaper_set_real_num_tx_queues(dev, txq); 3163 3164 dev_qdisc_change_real_num_tx(dev, txq); 3165 3166 dev->real_num_tx_queues = txq; 3167 3168 if (disabling) { 3169 synchronize_net(); 3170 qdisc_reset_all_tx_gt(dev, txq); 3171 #ifdef CONFIG_XPS 3172 netif_reset_xps_queues_gt(dev, txq); 3173 #endif 3174 } 3175 } else { 3176 dev->real_num_tx_queues = txq; 3177 } 3178 3179 return 0; 3180 } 3181 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 3182 3183 #ifdef CONFIG_SYSFS 3184 /** 3185 * netif_set_real_num_rx_queues - set actual number of RX queues used 3186 * @dev: Network device 3187 * @rxq: Actual number of RX queues 3188 * 3189 * This must be called either with the rtnl_lock held or before 3190 * registration of the net device. Returns 0 on success, or a 3191 * negative error code. If called before registration, it always 3192 * succeeds. 3193 */ 3194 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 3195 { 3196 int rc; 3197 3198 if (rxq < 1 || rxq > dev->num_rx_queues) 3199 return -EINVAL; 3200 3201 if (dev->reg_state == NETREG_REGISTERED) { 3202 ASSERT_RTNL(); 3203 3204 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 3205 rxq); 3206 if (rc) 3207 return rc; 3208 } 3209 3210 dev->real_num_rx_queues = rxq; 3211 return 0; 3212 } 3213 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 3214 #endif 3215 3216 /** 3217 * netif_set_real_num_queues - set actual number of RX and TX queues used 3218 * @dev: Network device 3219 * @txq: Actual number of TX queues 3220 * @rxq: Actual number of RX queues 3221 * 3222 * Set the real number of both TX and RX queues. 3223 * Does nothing if the number of queues is already correct. 3224 */ 3225 int netif_set_real_num_queues(struct net_device *dev, 3226 unsigned int txq, unsigned int rxq) 3227 { 3228 unsigned int old_rxq = dev->real_num_rx_queues; 3229 int err; 3230 3231 if (txq < 1 || txq > dev->num_tx_queues || 3232 rxq < 1 || rxq > dev->num_rx_queues) 3233 return -EINVAL; 3234 3235 /* Start from increases, so the error path only does decreases - 3236 * decreases can't fail. 3237 */ 3238 if (rxq > dev->real_num_rx_queues) { 3239 err = netif_set_real_num_rx_queues(dev, rxq); 3240 if (err) 3241 return err; 3242 } 3243 if (txq > dev->real_num_tx_queues) { 3244 err = netif_set_real_num_tx_queues(dev, txq); 3245 if (err) 3246 goto undo_rx; 3247 } 3248 if (rxq < dev->real_num_rx_queues) 3249 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 3250 if (txq < dev->real_num_tx_queues) 3251 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 3252 3253 return 0; 3254 undo_rx: 3255 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 3256 return err; 3257 } 3258 EXPORT_SYMBOL(netif_set_real_num_queues); 3259 3260 /** 3261 * netif_set_tso_max_size() - set the max size of TSO frames supported 3262 * @dev: netdev to update 3263 * @size: max skb->len of a TSO frame 3264 * 3265 * Set the limit on the size of TSO super-frames the device can handle. 3266 * Unless explicitly set the stack will assume the value of 3267 * %GSO_LEGACY_MAX_SIZE. 3268 */ 3269 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3270 { 3271 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3272 if (size < READ_ONCE(dev->gso_max_size)) 3273 netif_set_gso_max_size(dev, size); 3274 if (size < READ_ONCE(dev->gso_ipv4_max_size)) 3275 netif_set_gso_ipv4_max_size(dev, size); 3276 } 3277 EXPORT_SYMBOL(netif_set_tso_max_size); 3278 3279 /** 3280 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3281 * @dev: netdev to update 3282 * @segs: max number of TCP segments 3283 * 3284 * Set the limit on the number of TCP segments the device can generate from 3285 * a single TSO super-frame. 3286 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3287 */ 3288 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3289 { 3290 dev->tso_max_segs = segs; 3291 if (segs < READ_ONCE(dev->gso_max_segs)) 3292 netif_set_gso_max_segs(dev, segs); 3293 } 3294 EXPORT_SYMBOL(netif_set_tso_max_segs); 3295 3296 /** 3297 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3298 * @to: netdev to update 3299 * @from: netdev from which to copy the limits 3300 */ 3301 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3302 { 3303 netif_set_tso_max_size(to, from->tso_max_size); 3304 netif_set_tso_max_segs(to, from->tso_max_segs); 3305 } 3306 EXPORT_SYMBOL(netif_inherit_tso_max); 3307 3308 /** 3309 * netif_get_num_default_rss_queues - default number of RSS queues 3310 * 3311 * Default value is the number of physical cores if there are only 1 or 2, or 3312 * divided by 2 if there are more. 3313 */ 3314 int netif_get_num_default_rss_queues(void) 3315 { 3316 cpumask_var_t cpus; 3317 int cpu, count = 0; 3318 3319 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3320 return 1; 3321 3322 cpumask_copy(cpus, cpu_online_mask); 3323 for_each_cpu(cpu, cpus) { 3324 ++count; 3325 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3326 } 3327 free_cpumask_var(cpus); 3328 3329 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3330 } 3331 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3332 3333 static void __netif_reschedule(struct Qdisc *q) 3334 { 3335 struct softnet_data *sd; 3336 unsigned long flags; 3337 3338 local_irq_save(flags); 3339 sd = this_cpu_ptr(&softnet_data); 3340 q->next_sched = NULL; 3341 *sd->output_queue_tailp = q; 3342 sd->output_queue_tailp = &q->next_sched; 3343 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3344 local_irq_restore(flags); 3345 } 3346 3347 void __netif_schedule(struct Qdisc *q) 3348 { 3349 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3350 __netif_reschedule(q); 3351 } 3352 EXPORT_SYMBOL(__netif_schedule); 3353 3354 struct dev_kfree_skb_cb { 3355 enum skb_drop_reason reason; 3356 }; 3357 3358 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3359 { 3360 return (struct dev_kfree_skb_cb *)skb->cb; 3361 } 3362 3363 void netif_schedule_queue(struct netdev_queue *txq) 3364 { 3365 rcu_read_lock(); 3366 if (!netif_xmit_stopped(txq)) { 3367 struct Qdisc *q = rcu_dereference(txq->qdisc); 3368 3369 __netif_schedule(q); 3370 } 3371 rcu_read_unlock(); 3372 } 3373 EXPORT_SYMBOL(netif_schedule_queue); 3374 3375 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3376 { 3377 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3378 struct Qdisc *q; 3379 3380 rcu_read_lock(); 3381 q = rcu_dereference(dev_queue->qdisc); 3382 __netif_schedule(q); 3383 rcu_read_unlock(); 3384 } 3385 } 3386 EXPORT_SYMBOL(netif_tx_wake_queue); 3387 3388 void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3389 { 3390 unsigned long flags; 3391 3392 if (unlikely(!skb)) 3393 return; 3394 3395 if (likely(refcount_read(&skb->users) == 1)) { 3396 smp_rmb(); 3397 refcount_set(&skb->users, 0); 3398 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3399 return; 3400 } 3401 get_kfree_skb_cb(skb)->reason = reason; 3402 local_irq_save(flags); 3403 skb->next = __this_cpu_read(softnet_data.completion_queue); 3404 __this_cpu_write(softnet_data.completion_queue, skb); 3405 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3406 local_irq_restore(flags); 3407 } 3408 EXPORT_SYMBOL(dev_kfree_skb_irq_reason); 3409 3410 void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3411 { 3412 if (in_hardirq() || irqs_disabled()) 3413 dev_kfree_skb_irq_reason(skb, reason); 3414 else 3415 kfree_skb_reason(skb, reason); 3416 } 3417 EXPORT_SYMBOL(dev_kfree_skb_any_reason); 3418 3419 3420 /** 3421 * netif_device_detach - mark device as removed 3422 * @dev: network device 3423 * 3424 * Mark device as removed from system and therefore no longer available. 3425 */ 3426 void netif_device_detach(struct net_device *dev) 3427 { 3428 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3429 netif_running(dev)) { 3430 netif_tx_stop_all_queues(dev); 3431 } 3432 } 3433 EXPORT_SYMBOL(netif_device_detach); 3434 3435 /** 3436 * netif_device_attach - mark device as attached 3437 * @dev: network device 3438 * 3439 * Mark device as attached from system and restart if needed. 3440 */ 3441 void netif_device_attach(struct net_device *dev) 3442 { 3443 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3444 netif_running(dev)) { 3445 netif_tx_wake_all_queues(dev); 3446 netdev_watchdog_up(dev); 3447 } 3448 } 3449 EXPORT_SYMBOL(netif_device_attach); 3450 3451 /* 3452 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3453 * to be used as a distribution range. 3454 */ 3455 static u16 skb_tx_hash(const struct net_device *dev, 3456 const struct net_device *sb_dev, 3457 struct sk_buff *skb) 3458 { 3459 u32 hash; 3460 u16 qoffset = 0; 3461 u16 qcount = dev->real_num_tx_queues; 3462 3463 if (dev->num_tc) { 3464 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3465 3466 qoffset = sb_dev->tc_to_txq[tc].offset; 3467 qcount = sb_dev->tc_to_txq[tc].count; 3468 if (unlikely(!qcount)) { 3469 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3470 sb_dev->name, qoffset, tc); 3471 qoffset = 0; 3472 qcount = dev->real_num_tx_queues; 3473 } 3474 } 3475 3476 if (skb_rx_queue_recorded(skb)) { 3477 DEBUG_NET_WARN_ON_ONCE(qcount == 0); 3478 hash = skb_get_rx_queue(skb); 3479 if (hash >= qoffset) 3480 hash -= qoffset; 3481 while (unlikely(hash >= qcount)) 3482 hash -= qcount; 3483 return hash + qoffset; 3484 } 3485 3486 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3487 } 3488 3489 void skb_warn_bad_offload(const struct sk_buff *skb) 3490 { 3491 static const netdev_features_t null_features; 3492 struct net_device *dev = skb->dev; 3493 const char *name = ""; 3494 3495 if (!net_ratelimit()) 3496 return; 3497 3498 if (dev) { 3499 if (dev->dev.parent) 3500 name = dev_driver_string(dev->dev.parent); 3501 else 3502 name = netdev_name(dev); 3503 } 3504 skb_dump(KERN_WARNING, skb, false); 3505 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3506 name, dev ? &dev->features : &null_features, 3507 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3508 } 3509 3510 /* 3511 * Invalidate hardware checksum when packet is to be mangled, and 3512 * complete checksum manually on outgoing path. 3513 */ 3514 int skb_checksum_help(struct sk_buff *skb) 3515 { 3516 __wsum csum; 3517 int ret = 0, offset; 3518 3519 if (skb->ip_summed == CHECKSUM_COMPLETE) 3520 goto out_set_summed; 3521 3522 if (unlikely(skb_is_gso(skb))) { 3523 skb_warn_bad_offload(skb); 3524 return -EINVAL; 3525 } 3526 3527 if (!skb_frags_readable(skb)) { 3528 return -EFAULT; 3529 } 3530 3531 /* Before computing a checksum, we should make sure no frag could 3532 * be modified by an external entity : checksum could be wrong. 3533 */ 3534 if (skb_has_shared_frag(skb)) { 3535 ret = __skb_linearize(skb); 3536 if (ret) 3537 goto out; 3538 } 3539 3540 offset = skb_checksum_start_offset(skb); 3541 ret = -EINVAL; 3542 if (unlikely(offset >= skb_headlen(skb))) { 3543 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3544 WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n", 3545 offset, skb_headlen(skb)); 3546 goto out; 3547 } 3548 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3549 3550 offset += skb->csum_offset; 3551 if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) { 3552 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3553 WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n", 3554 offset + sizeof(__sum16), skb_headlen(skb)); 3555 goto out; 3556 } 3557 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3558 if (ret) 3559 goto out; 3560 3561 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3562 out_set_summed: 3563 skb->ip_summed = CHECKSUM_NONE; 3564 out: 3565 return ret; 3566 } 3567 EXPORT_SYMBOL(skb_checksum_help); 3568 3569 int skb_crc32c_csum_help(struct sk_buff *skb) 3570 { 3571 __le32 crc32c_csum; 3572 int ret = 0, offset, start; 3573 3574 if (skb->ip_summed != CHECKSUM_PARTIAL) 3575 goto out; 3576 3577 if (unlikely(skb_is_gso(skb))) 3578 goto out; 3579 3580 /* Before computing a checksum, we should make sure no frag could 3581 * be modified by an external entity : checksum could be wrong. 3582 */ 3583 if (unlikely(skb_has_shared_frag(skb))) { 3584 ret = __skb_linearize(skb); 3585 if (ret) 3586 goto out; 3587 } 3588 start = skb_checksum_start_offset(skb); 3589 offset = start + offsetof(struct sctphdr, checksum); 3590 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3591 ret = -EINVAL; 3592 goto out; 3593 } 3594 3595 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3596 if (ret) 3597 goto out; 3598 3599 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3600 skb->len - start, ~(__u32)0, 3601 crc32c_csum_stub)); 3602 *(__le32 *)(skb->data + offset) = crc32c_csum; 3603 skb_reset_csum_not_inet(skb); 3604 out: 3605 return ret; 3606 } 3607 EXPORT_SYMBOL(skb_crc32c_csum_help); 3608 3609 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3610 { 3611 __be16 type = skb->protocol; 3612 3613 /* Tunnel gso handlers can set protocol to ethernet. */ 3614 if (type == htons(ETH_P_TEB)) { 3615 struct ethhdr *eth; 3616 3617 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3618 return 0; 3619 3620 eth = (struct ethhdr *)skb->data; 3621 type = eth->h_proto; 3622 } 3623 3624 return vlan_get_protocol_and_depth(skb, type, depth); 3625 } 3626 3627 3628 /* Take action when hardware reception checksum errors are detected. */ 3629 #ifdef CONFIG_BUG 3630 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3631 { 3632 netdev_err(dev, "hw csum failure\n"); 3633 skb_dump(KERN_ERR, skb, true); 3634 dump_stack(); 3635 } 3636 3637 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3638 { 3639 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3640 } 3641 EXPORT_SYMBOL(netdev_rx_csum_fault); 3642 #endif 3643 3644 /* XXX: check that highmem exists at all on the given machine. */ 3645 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3646 { 3647 #ifdef CONFIG_HIGHMEM 3648 int i; 3649 3650 if (!(dev->features & NETIF_F_HIGHDMA)) { 3651 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3652 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3653 struct page *page = skb_frag_page(frag); 3654 3655 if (page && PageHighMem(page)) 3656 return 1; 3657 } 3658 } 3659 #endif 3660 return 0; 3661 } 3662 3663 /* If MPLS offload request, verify we are testing hardware MPLS features 3664 * instead of standard features for the netdev. 3665 */ 3666 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3667 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3668 netdev_features_t features, 3669 __be16 type) 3670 { 3671 if (eth_p_mpls(type)) 3672 features &= skb->dev->mpls_features; 3673 3674 return features; 3675 } 3676 #else 3677 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3678 netdev_features_t features, 3679 __be16 type) 3680 { 3681 return features; 3682 } 3683 #endif 3684 3685 static netdev_features_t harmonize_features(struct sk_buff *skb, 3686 netdev_features_t features) 3687 { 3688 __be16 type; 3689 3690 type = skb_network_protocol(skb, NULL); 3691 features = net_mpls_features(skb, features, type); 3692 3693 if (skb->ip_summed != CHECKSUM_NONE && 3694 !can_checksum_protocol(features, type)) { 3695 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3696 } 3697 if (illegal_highdma(skb->dev, skb)) 3698 features &= ~NETIF_F_SG; 3699 3700 return features; 3701 } 3702 3703 netdev_features_t passthru_features_check(struct sk_buff *skb, 3704 struct net_device *dev, 3705 netdev_features_t features) 3706 { 3707 return features; 3708 } 3709 EXPORT_SYMBOL(passthru_features_check); 3710 3711 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3712 struct net_device *dev, 3713 netdev_features_t features) 3714 { 3715 return vlan_features_check(skb, features); 3716 } 3717 3718 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3719 struct net_device *dev, 3720 netdev_features_t features) 3721 { 3722 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3723 3724 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3725 return features & ~NETIF_F_GSO_MASK; 3726 3727 if (unlikely(skb->len >= netif_get_gso_max_size(dev, skb))) 3728 return features & ~NETIF_F_GSO_MASK; 3729 3730 if (!skb_shinfo(skb)->gso_type) { 3731 skb_warn_bad_offload(skb); 3732 return features & ~NETIF_F_GSO_MASK; 3733 } 3734 3735 /* Support for GSO partial features requires software 3736 * intervention before we can actually process the packets 3737 * so we need to strip support for any partial features now 3738 * and we can pull them back in after we have partially 3739 * segmented the frame. 3740 */ 3741 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3742 features &= ~dev->gso_partial_features; 3743 3744 /* Make sure to clear the IPv4 ID mangling feature if the 3745 * IPv4 header has the potential to be fragmented. 3746 */ 3747 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3748 struct iphdr *iph = skb->encapsulation ? 3749 inner_ip_hdr(skb) : ip_hdr(skb); 3750 3751 if (!(iph->frag_off & htons(IP_DF))) 3752 features &= ~NETIF_F_TSO_MANGLEID; 3753 } 3754 3755 return features; 3756 } 3757 3758 netdev_features_t netif_skb_features(struct sk_buff *skb) 3759 { 3760 struct net_device *dev = skb->dev; 3761 netdev_features_t features = dev->features; 3762 3763 if (skb_is_gso(skb)) 3764 features = gso_features_check(skb, dev, features); 3765 3766 /* If encapsulation offload request, verify we are testing 3767 * hardware encapsulation features instead of standard 3768 * features for the netdev 3769 */ 3770 if (skb->encapsulation) 3771 features &= dev->hw_enc_features; 3772 3773 if (skb_vlan_tagged(skb)) 3774 features = netdev_intersect_features(features, 3775 dev->vlan_features | 3776 NETIF_F_HW_VLAN_CTAG_TX | 3777 NETIF_F_HW_VLAN_STAG_TX); 3778 3779 if (dev->netdev_ops->ndo_features_check) 3780 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3781 features); 3782 else 3783 features &= dflt_features_check(skb, dev, features); 3784 3785 return harmonize_features(skb, features); 3786 } 3787 EXPORT_SYMBOL(netif_skb_features); 3788 3789 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3790 struct netdev_queue *txq, bool more) 3791 { 3792 unsigned int len; 3793 int rc; 3794 3795 if (dev_nit_active(dev)) 3796 dev_queue_xmit_nit(skb, dev); 3797 3798 len = skb->len; 3799 trace_net_dev_start_xmit(skb, dev); 3800 rc = netdev_start_xmit(skb, dev, txq, more); 3801 trace_net_dev_xmit(skb, rc, dev, len); 3802 3803 return rc; 3804 } 3805 3806 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3807 struct netdev_queue *txq, int *ret) 3808 { 3809 struct sk_buff *skb = first; 3810 int rc = NETDEV_TX_OK; 3811 3812 while (skb) { 3813 struct sk_buff *next = skb->next; 3814 3815 skb_mark_not_on_list(skb); 3816 rc = xmit_one(skb, dev, txq, next != NULL); 3817 if (unlikely(!dev_xmit_complete(rc))) { 3818 skb->next = next; 3819 goto out; 3820 } 3821 3822 skb = next; 3823 if (netif_tx_queue_stopped(txq) && skb) { 3824 rc = NETDEV_TX_BUSY; 3825 break; 3826 } 3827 } 3828 3829 out: 3830 *ret = rc; 3831 return skb; 3832 } 3833 3834 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3835 netdev_features_t features) 3836 { 3837 if (skb_vlan_tag_present(skb) && 3838 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3839 skb = __vlan_hwaccel_push_inside(skb); 3840 return skb; 3841 } 3842 3843 int skb_csum_hwoffload_help(struct sk_buff *skb, 3844 const netdev_features_t features) 3845 { 3846 if (unlikely(skb_csum_is_sctp(skb))) 3847 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3848 skb_crc32c_csum_help(skb); 3849 3850 if (features & NETIF_F_HW_CSUM) 3851 return 0; 3852 3853 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3854 if (vlan_get_protocol(skb) == htons(ETH_P_IPV6) && 3855 skb_network_header_len(skb) != sizeof(struct ipv6hdr) && 3856 !ipv6_has_hopopt_jumbo(skb)) 3857 goto sw_checksum; 3858 3859 switch (skb->csum_offset) { 3860 case offsetof(struct tcphdr, check): 3861 case offsetof(struct udphdr, check): 3862 return 0; 3863 } 3864 } 3865 3866 sw_checksum: 3867 return skb_checksum_help(skb); 3868 } 3869 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3870 3871 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3872 { 3873 netdev_features_t features; 3874 3875 if (!skb_frags_readable(skb)) 3876 goto out_kfree_skb; 3877 3878 features = netif_skb_features(skb); 3879 skb = validate_xmit_vlan(skb, features); 3880 if (unlikely(!skb)) 3881 goto out_null; 3882 3883 skb = sk_validate_xmit_skb(skb, dev); 3884 if (unlikely(!skb)) 3885 goto out_null; 3886 3887 if (netif_needs_gso(skb, features)) { 3888 struct sk_buff *segs; 3889 3890 segs = skb_gso_segment(skb, features); 3891 if (IS_ERR(segs)) { 3892 goto out_kfree_skb; 3893 } else if (segs) { 3894 consume_skb(skb); 3895 skb = segs; 3896 } 3897 } else { 3898 if (skb_needs_linearize(skb, features) && 3899 __skb_linearize(skb)) 3900 goto out_kfree_skb; 3901 3902 /* If packet is not checksummed and device does not 3903 * support checksumming for this protocol, complete 3904 * checksumming here. 3905 */ 3906 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3907 if (skb->encapsulation) 3908 skb_set_inner_transport_header(skb, 3909 skb_checksum_start_offset(skb)); 3910 else 3911 skb_set_transport_header(skb, 3912 skb_checksum_start_offset(skb)); 3913 if (skb_csum_hwoffload_help(skb, features)) 3914 goto out_kfree_skb; 3915 } 3916 } 3917 3918 skb = validate_xmit_xfrm(skb, features, again); 3919 3920 return skb; 3921 3922 out_kfree_skb: 3923 kfree_skb(skb); 3924 out_null: 3925 dev_core_stats_tx_dropped_inc(dev); 3926 return NULL; 3927 } 3928 3929 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3930 { 3931 struct sk_buff *next, *head = NULL, *tail; 3932 3933 for (; skb != NULL; skb = next) { 3934 next = skb->next; 3935 skb_mark_not_on_list(skb); 3936 3937 /* in case skb won't be segmented, point to itself */ 3938 skb->prev = skb; 3939 3940 skb = validate_xmit_skb(skb, dev, again); 3941 if (!skb) 3942 continue; 3943 3944 if (!head) 3945 head = skb; 3946 else 3947 tail->next = skb; 3948 /* If skb was segmented, skb->prev points to 3949 * the last segment. If not, it still contains skb. 3950 */ 3951 tail = skb->prev; 3952 } 3953 return head; 3954 } 3955 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3956 3957 static void qdisc_pkt_len_init(struct sk_buff *skb) 3958 { 3959 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3960 3961 qdisc_skb_cb(skb)->pkt_len = skb->len; 3962 3963 /* To get more precise estimation of bytes sent on wire, 3964 * we add to pkt_len the headers size of all segments 3965 */ 3966 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3967 u16 gso_segs = shinfo->gso_segs; 3968 unsigned int hdr_len; 3969 3970 /* mac layer + network layer */ 3971 hdr_len = skb_transport_offset(skb); 3972 3973 /* + transport layer */ 3974 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3975 const struct tcphdr *th; 3976 struct tcphdr _tcphdr; 3977 3978 th = skb_header_pointer(skb, hdr_len, 3979 sizeof(_tcphdr), &_tcphdr); 3980 if (likely(th)) 3981 hdr_len += __tcp_hdrlen(th); 3982 } else if (shinfo->gso_type & SKB_GSO_UDP_L4) { 3983 struct udphdr _udphdr; 3984 3985 if (skb_header_pointer(skb, hdr_len, 3986 sizeof(_udphdr), &_udphdr)) 3987 hdr_len += sizeof(struct udphdr); 3988 } 3989 3990 if (unlikely(shinfo->gso_type & SKB_GSO_DODGY)) { 3991 int payload = skb->len - hdr_len; 3992 3993 /* Malicious packet. */ 3994 if (payload <= 0) 3995 return; 3996 gso_segs = DIV_ROUND_UP(payload, shinfo->gso_size); 3997 } 3998 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3999 } 4000 } 4001 4002 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 4003 struct sk_buff **to_free, 4004 struct netdev_queue *txq) 4005 { 4006 int rc; 4007 4008 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 4009 if (rc == NET_XMIT_SUCCESS) 4010 trace_qdisc_enqueue(q, txq, skb); 4011 return rc; 4012 } 4013 4014 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 4015 struct net_device *dev, 4016 struct netdev_queue *txq) 4017 { 4018 spinlock_t *root_lock = qdisc_lock(q); 4019 struct sk_buff *to_free = NULL; 4020 bool contended; 4021 int rc; 4022 4023 qdisc_calculate_pkt_len(skb, q); 4024 4025 tcf_set_drop_reason(skb, SKB_DROP_REASON_QDISC_DROP); 4026 4027 if (q->flags & TCQ_F_NOLOCK) { 4028 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 4029 qdisc_run_begin(q)) { 4030 /* Retest nolock_qdisc_is_empty() within the protection 4031 * of q->seqlock to protect from racing with requeuing. 4032 */ 4033 if (unlikely(!nolock_qdisc_is_empty(q))) { 4034 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4035 __qdisc_run(q); 4036 qdisc_run_end(q); 4037 4038 goto no_lock_out; 4039 } 4040 4041 qdisc_bstats_cpu_update(q, skb); 4042 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 4043 !nolock_qdisc_is_empty(q)) 4044 __qdisc_run(q); 4045 4046 qdisc_run_end(q); 4047 return NET_XMIT_SUCCESS; 4048 } 4049 4050 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4051 qdisc_run(q); 4052 4053 no_lock_out: 4054 if (unlikely(to_free)) 4055 kfree_skb_list_reason(to_free, 4056 tcf_get_drop_reason(to_free)); 4057 return rc; 4058 } 4059 4060 if (unlikely(READ_ONCE(q->owner) == smp_processor_id())) { 4061 kfree_skb_reason(skb, SKB_DROP_REASON_TC_RECLASSIFY_LOOP); 4062 return NET_XMIT_DROP; 4063 } 4064 /* 4065 * Heuristic to force contended enqueues to serialize on a 4066 * separate lock before trying to get qdisc main lock. 4067 * This permits qdisc->running owner to get the lock more 4068 * often and dequeue packets faster. 4069 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 4070 * and then other tasks will only enqueue packets. The packets will be 4071 * sent after the qdisc owner is scheduled again. To prevent this 4072 * scenario the task always serialize on the lock. 4073 */ 4074 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 4075 if (unlikely(contended)) 4076 spin_lock(&q->busylock); 4077 4078 spin_lock(root_lock); 4079 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 4080 __qdisc_drop(skb, &to_free); 4081 rc = NET_XMIT_DROP; 4082 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 4083 qdisc_run_begin(q)) { 4084 /* 4085 * This is a work-conserving queue; there are no old skbs 4086 * waiting to be sent out; and the qdisc is not running - 4087 * xmit the skb directly. 4088 */ 4089 4090 qdisc_bstats_update(q, skb); 4091 4092 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 4093 if (unlikely(contended)) { 4094 spin_unlock(&q->busylock); 4095 contended = false; 4096 } 4097 __qdisc_run(q); 4098 } 4099 4100 qdisc_run_end(q); 4101 rc = NET_XMIT_SUCCESS; 4102 } else { 4103 WRITE_ONCE(q->owner, smp_processor_id()); 4104 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4105 WRITE_ONCE(q->owner, -1); 4106 if (qdisc_run_begin(q)) { 4107 if (unlikely(contended)) { 4108 spin_unlock(&q->busylock); 4109 contended = false; 4110 } 4111 __qdisc_run(q); 4112 qdisc_run_end(q); 4113 } 4114 } 4115 spin_unlock(root_lock); 4116 if (unlikely(to_free)) 4117 kfree_skb_list_reason(to_free, 4118 tcf_get_drop_reason(to_free)); 4119 if (unlikely(contended)) 4120 spin_unlock(&q->busylock); 4121 return rc; 4122 } 4123 4124 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 4125 static void skb_update_prio(struct sk_buff *skb) 4126 { 4127 const struct netprio_map *map; 4128 const struct sock *sk; 4129 unsigned int prioidx; 4130 4131 if (skb->priority) 4132 return; 4133 map = rcu_dereference_bh(skb->dev->priomap); 4134 if (!map) 4135 return; 4136 sk = skb_to_full_sk(skb); 4137 if (!sk) 4138 return; 4139 4140 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 4141 4142 if (prioidx < map->priomap_len) 4143 skb->priority = map->priomap[prioidx]; 4144 } 4145 #else 4146 #define skb_update_prio(skb) 4147 #endif 4148 4149 /** 4150 * dev_loopback_xmit - loop back @skb 4151 * @net: network namespace this loopback is happening in 4152 * @sk: sk needed to be a netfilter okfn 4153 * @skb: buffer to transmit 4154 */ 4155 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 4156 { 4157 skb_reset_mac_header(skb); 4158 __skb_pull(skb, skb_network_offset(skb)); 4159 skb->pkt_type = PACKET_LOOPBACK; 4160 if (skb->ip_summed == CHECKSUM_NONE) 4161 skb->ip_summed = CHECKSUM_UNNECESSARY; 4162 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 4163 skb_dst_force(skb); 4164 netif_rx(skb); 4165 return 0; 4166 } 4167 EXPORT_SYMBOL(dev_loopback_xmit); 4168 4169 #ifdef CONFIG_NET_EGRESS 4170 static struct netdev_queue * 4171 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 4172 { 4173 int qm = skb_get_queue_mapping(skb); 4174 4175 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 4176 } 4177 4178 #ifndef CONFIG_PREEMPT_RT 4179 static bool netdev_xmit_txqueue_skipped(void) 4180 { 4181 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 4182 } 4183 4184 void netdev_xmit_skip_txqueue(bool skip) 4185 { 4186 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 4187 } 4188 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 4189 4190 #else 4191 static bool netdev_xmit_txqueue_skipped(void) 4192 { 4193 return current->net_xmit.skip_txqueue; 4194 } 4195 4196 void netdev_xmit_skip_txqueue(bool skip) 4197 { 4198 current->net_xmit.skip_txqueue = skip; 4199 } 4200 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 4201 #endif 4202 #endif /* CONFIG_NET_EGRESS */ 4203 4204 #ifdef CONFIG_NET_XGRESS 4205 static int tc_run(struct tcx_entry *entry, struct sk_buff *skb, 4206 enum skb_drop_reason *drop_reason) 4207 { 4208 int ret = TC_ACT_UNSPEC; 4209 #ifdef CONFIG_NET_CLS_ACT 4210 struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq); 4211 struct tcf_result res; 4212 4213 if (!miniq) 4214 return ret; 4215 4216 /* Global bypass */ 4217 if (!static_branch_likely(&tcf_sw_enabled_key)) 4218 return ret; 4219 4220 /* Block-wise bypass */ 4221 if (tcf_block_bypass_sw(miniq->block)) 4222 return ret; 4223 4224 tc_skb_cb(skb)->mru = 0; 4225 tc_skb_cb(skb)->post_ct = false; 4226 tcf_set_drop_reason(skb, *drop_reason); 4227 4228 mini_qdisc_bstats_cpu_update(miniq, skb); 4229 ret = tcf_classify(skb, miniq->block, miniq->filter_list, &res, false); 4230 /* Only tcf related quirks below. */ 4231 switch (ret) { 4232 case TC_ACT_SHOT: 4233 *drop_reason = tcf_get_drop_reason(skb); 4234 mini_qdisc_qstats_cpu_drop(miniq); 4235 break; 4236 case TC_ACT_OK: 4237 case TC_ACT_RECLASSIFY: 4238 skb->tc_index = TC_H_MIN(res.classid); 4239 break; 4240 } 4241 #endif /* CONFIG_NET_CLS_ACT */ 4242 return ret; 4243 } 4244 4245 static DEFINE_STATIC_KEY_FALSE(tcx_needed_key); 4246 4247 void tcx_inc(void) 4248 { 4249 static_branch_inc(&tcx_needed_key); 4250 } 4251 4252 void tcx_dec(void) 4253 { 4254 static_branch_dec(&tcx_needed_key); 4255 } 4256 4257 static __always_inline enum tcx_action_base 4258 tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb, 4259 const bool needs_mac) 4260 { 4261 const struct bpf_mprog_fp *fp; 4262 const struct bpf_prog *prog; 4263 int ret = TCX_NEXT; 4264 4265 if (needs_mac) 4266 __skb_push(skb, skb->mac_len); 4267 bpf_mprog_foreach_prog(entry, fp, prog) { 4268 bpf_compute_data_pointers(skb); 4269 ret = bpf_prog_run(prog, skb); 4270 if (ret != TCX_NEXT) 4271 break; 4272 } 4273 if (needs_mac) 4274 __skb_pull(skb, skb->mac_len); 4275 return tcx_action_code(skb, ret); 4276 } 4277 4278 static __always_inline struct sk_buff * 4279 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4280 struct net_device *orig_dev, bool *another) 4281 { 4282 struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress); 4283 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_INGRESS; 4284 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 4285 int sch_ret; 4286 4287 if (!entry) 4288 return skb; 4289 4290 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 4291 if (*pt_prev) { 4292 *ret = deliver_skb(skb, *pt_prev, orig_dev); 4293 *pt_prev = NULL; 4294 } 4295 4296 qdisc_skb_cb(skb)->pkt_len = skb->len; 4297 tcx_set_ingress(skb, true); 4298 4299 if (static_branch_unlikely(&tcx_needed_key)) { 4300 sch_ret = tcx_run(entry, skb, true); 4301 if (sch_ret != TC_ACT_UNSPEC) 4302 goto ingress_verdict; 4303 } 4304 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4305 ingress_verdict: 4306 switch (sch_ret) { 4307 case TC_ACT_REDIRECT: 4308 /* skb_mac_header check was done by BPF, so we can safely 4309 * push the L2 header back before redirecting to another 4310 * netdev. 4311 */ 4312 __skb_push(skb, skb->mac_len); 4313 if (skb_do_redirect(skb) == -EAGAIN) { 4314 __skb_pull(skb, skb->mac_len); 4315 *another = true; 4316 break; 4317 } 4318 *ret = NET_RX_SUCCESS; 4319 bpf_net_ctx_clear(bpf_net_ctx); 4320 return NULL; 4321 case TC_ACT_SHOT: 4322 kfree_skb_reason(skb, drop_reason); 4323 *ret = NET_RX_DROP; 4324 bpf_net_ctx_clear(bpf_net_ctx); 4325 return NULL; 4326 /* used by tc_run */ 4327 case TC_ACT_STOLEN: 4328 case TC_ACT_QUEUED: 4329 case TC_ACT_TRAP: 4330 consume_skb(skb); 4331 fallthrough; 4332 case TC_ACT_CONSUMED: 4333 *ret = NET_RX_SUCCESS; 4334 bpf_net_ctx_clear(bpf_net_ctx); 4335 return NULL; 4336 } 4337 bpf_net_ctx_clear(bpf_net_ctx); 4338 4339 return skb; 4340 } 4341 4342 static __always_inline struct sk_buff * 4343 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4344 { 4345 struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress); 4346 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_EGRESS; 4347 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 4348 int sch_ret; 4349 4350 if (!entry) 4351 return skb; 4352 4353 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 4354 4355 /* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was 4356 * already set by the caller. 4357 */ 4358 if (static_branch_unlikely(&tcx_needed_key)) { 4359 sch_ret = tcx_run(entry, skb, false); 4360 if (sch_ret != TC_ACT_UNSPEC) 4361 goto egress_verdict; 4362 } 4363 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4364 egress_verdict: 4365 switch (sch_ret) { 4366 case TC_ACT_REDIRECT: 4367 /* No need to push/pop skb's mac_header here on egress! */ 4368 skb_do_redirect(skb); 4369 *ret = NET_XMIT_SUCCESS; 4370 bpf_net_ctx_clear(bpf_net_ctx); 4371 return NULL; 4372 case TC_ACT_SHOT: 4373 kfree_skb_reason(skb, drop_reason); 4374 *ret = NET_XMIT_DROP; 4375 bpf_net_ctx_clear(bpf_net_ctx); 4376 return NULL; 4377 /* used by tc_run */ 4378 case TC_ACT_STOLEN: 4379 case TC_ACT_QUEUED: 4380 case TC_ACT_TRAP: 4381 consume_skb(skb); 4382 fallthrough; 4383 case TC_ACT_CONSUMED: 4384 *ret = NET_XMIT_SUCCESS; 4385 bpf_net_ctx_clear(bpf_net_ctx); 4386 return NULL; 4387 } 4388 bpf_net_ctx_clear(bpf_net_ctx); 4389 4390 return skb; 4391 } 4392 #else 4393 static __always_inline struct sk_buff * 4394 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4395 struct net_device *orig_dev, bool *another) 4396 { 4397 return skb; 4398 } 4399 4400 static __always_inline struct sk_buff * 4401 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4402 { 4403 return skb; 4404 } 4405 #endif /* CONFIG_NET_XGRESS */ 4406 4407 #ifdef CONFIG_XPS 4408 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4409 struct xps_dev_maps *dev_maps, unsigned int tci) 4410 { 4411 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4412 struct xps_map *map; 4413 int queue_index = -1; 4414 4415 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4416 return queue_index; 4417 4418 tci *= dev_maps->num_tc; 4419 tci += tc; 4420 4421 map = rcu_dereference(dev_maps->attr_map[tci]); 4422 if (map) { 4423 if (map->len == 1) 4424 queue_index = map->queues[0]; 4425 else 4426 queue_index = map->queues[reciprocal_scale( 4427 skb_get_hash(skb), map->len)]; 4428 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4429 queue_index = -1; 4430 } 4431 return queue_index; 4432 } 4433 #endif 4434 4435 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4436 struct sk_buff *skb) 4437 { 4438 #ifdef CONFIG_XPS 4439 struct xps_dev_maps *dev_maps; 4440 struct sock *sk = skb->sk; 4441 int queue_index = -1; 4442 4443 if (!static_key_false(&xps_needed)) 4444 return -1; 4445 4446 rcu_read_lock(); 4447 if (!static_key_false(&xps_rxqs_needed)) 4448 goto get_cpus_map; 4449 4450 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4451 if (dev_maps) { 4452 int tci = sk_rx_queue_get(sk); 4453 4454 if (tci >= 0) 4455 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4456 tci); 4457 } 4458 4459 get_cpus_map: 4460 if (queue_index < 0) { 4461 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4462 if (dev_maps) { 4463 unsigned int tci = skb->sender_cpu - 1; 4464 4465 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4466 tci); 4467 } 4468 } 4469 rcu_read_unlock(); 4470 4471 return queue_index; 4472 #else 4473 return -1; 4474 #endif 4475 } 4476 4477 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4478 struct net_device *sb_dev) 4479 { 4480 return 0; 4481 } 4482 EXPORT_SYMBOL(dev_pick_tx_zero); 4483 4484 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4485 struct net_device *sb_dev) 4486 { 4487 struct sock *sk = skb->sk; 4488 int queue_index = sk_tx_queue_get(sk); 4489 4490 sb_dev = sb_dev ? : dev; 4491 4492 if (queue_index < 0 || skb->ooo_okay || 4493 queue_index >= dev->real_num_tx_queues) { 4494 int new_index = get_xps_queue(dev, sb_dev, skb); 4495 4496 if (new_index < 0) 4497 new_index = skb_tx_hash(dev, sb_dev, skb); 4498 4499 if (queue_index != new_index && sk && 4500 sk_fullsock(sk) && 4501 rcu_access_pointer(sk->sk_dst_cache)) 4502 sk_tx_queue_set(sk, new_index); 4503 4504 queue_index = new_index; 4505 } 4506 4507 return queue_index; 4508 } 4509 EXPORT_SYMBOL(netdev_pick_tx); 4510 4511 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4512 struct sk_buff *skb, 4513 struct net_device *sb_dev) 4514 { 4515 int queue_index = 0; 4516 4517 #ifdef CONFIG_XPS 4518 u32 sender_cpu = skb->sender_cpu - 1; 4519 4520 if (sender_cpu >= (u32)NR_CPUS) 4521 skb->sender_cpu = raw_smp_processor_id() + 1; 4522 #endif 4523 4524 if (dev->real_num_tx_queues != 1) { 4525 const struct net_device_ops *ops = dev->netdev_ops; 4526 4527 if (ops->ndo_select_queue) 4528 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4529 else 4530 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4531 4532 queue_index = netdev_cap_txqueue(dev, queue_index); 4533 } 4534 4535 skb_set_queue_mapping(skb, queue_index); 4536 return netdev_get_tx_queue(dev, queue_index); 4537 } 4538 4539 /** 4540 * __dev_queue_xmit() - transmit a buffer 4541 * @skb: buffer to transmit 4542 * @sb_dev: suboordinate device used for L2 forwarding offload 4543 * 4544 * Queue a buffer for transmission to a network device. The caller must 4545 * have set the device and priority and built the buffer before calling 4546 * this function. The function can be called from an interrupt. 4547 * 4548 * When calling this method, interrupts MUST be enabled. This is because 4549 * the BH enable code must have IRQs enabled so that it will not deadlock. 4550 * 4551 * Regardless of the return value, the skb is consumed, so it is currently 4552 * difficult to retry a send to this method. (You can bump the ref count 4553 * before sending to hold a reference for retry if you are careful.) 4554 * 4555 * Return: 4556 * * 0 - buffer successfully transmitted 4557 * * positive qdisc return code - NET_XMIT_DROP etc. 4558 * * negative errno - other errors 4559 */ 4560 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4561 { 4562 struct net_device *dev = skb->dev; 4563 struct netdev_queue *txq = NULL; 4564 struct Qdisc *q; 4565 int rc = -ENOMEM; 4566 bool again = false; 4567 4568 skb_reset_mac_header(skb); 4569 skb_assert_len(skb); 4570 4571 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4572 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4573 4574 /* Disable soft irqs for various locks below. Also 4575 * stops preemption for RCU. 4576 */ 4577 rcu_read_lock_bh(); 4578 4579 skb_update_prio(skb); 4580 4581 qdisc_pkt_len_init(skb); 4582 tcx_set_ingress(skb, false); 4583 #ifdef CONFIG_NET_EGRESS 4584 if (static_branch_unlikely(&egress_needed_key)) { 4585 if (nf_hook_egress_active()) { 4586 skb = nf_hook_egress(skb, &rc, dev); 4587 if (!skb) 4588 goto out; 4589 } 4590 4591 netdev_xmit_skip_txqueue(false); 4592 4593 nf_skip_egress(skb, true); 4594 skb = sch_handle_egress(skb, &rc, dev); 4595 if (!skb) 4596 goto out; 4597 nf_skip_egress(skb, false); 4598 4599 if (netdev_xmit_txqueue_skipped()) 4600 txq = netdev_tx_queue_mapping(dev, skb); 4601 } 4602 #endif 4603 /* If device/qdisc don't need skb->dst, release it right now while 4604 * its hot in this cpu cache. 4605 */ 4606 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4607 skb_dst_drop(skb); 4608 else 4609 skb_dst_force(skb); 4610 4611 if (!txq) 4612 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4613 4614 q = rcu_dereference_bh(txq->qdisc); 4615 4616 trace_net_dev_queue(skb); 4617 if (q->enqueue) { 4618 rc = __dev_xmit_skb(skb, q, dev, txq); 4619 goto out; 4620 } 4621 4622 /* The device has no queue. Common case for software devices: 4623 * loopback, all the sorts of tunnels... 4624 4625 * Really, it is unlikely that netif_tx_lock protection is necessary 4626 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4627 * counters.) 4628 * However, it is possible, that they rely on protection 4629 * made by us here. 4630 4631 * Check this and shot the lock. It is not prone from deadlocks. 4632 *Either shot noqueue qdisc, it is even simpler 8) 4633 */ 4634 if (dev->flags & IFF_UP) { 4635 int cpu = smp_processor_id(); /* ok because BHs are off */ 4636 4637 /* Other cpus might concurrently change txq->xmit_lock_owner 4638 * to -1 or to their cpu id, but not to our id. 4639 */ 4640 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4641 if (dev_xmit_recursion()) 4642 goto recursion_alert; 4643 4644 skb = validate_xmit_skb(skb, dev, &again); 4645 if (!skb) 4646 goto out; 4647 4648 HARD_TX_LOCK(dev, txq, cpu); 4649 4650 if (!netif_xmit_stopped(txq)) { 4651 dev_xmit_recursion_inc(); 4652 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4653 dev_xmit_recursion_dec(); 4654 if (dev_xmit_complete(rc)) { 4655 HARD_TX_UNLOCK(dev, txq); 4656 goto out; 4657 } 4658 } 4659 HARD_TX_UNLOCK(dev, txq); 4660 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4661 dev->name); 4662 } else { 4663 /* Recursion is detected! It is possible, 4664 * unfortunately 4665 */ 4666 recursion_alert: 4667 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4668 dev->name); 4669 } 4670 } 4671 4672 rc = -ENETDOWN; 4673 rcu_read_unlock_bh(); 4674 4675 dev_core_stats_tx_dropped_inc(dev); 4676 kfree_skb_list(skb); 4677 return rc; 4678 out: 4679 rcu_read_unlock_bh(); 4680 return rc; 4681 } 4682 EXPORT_SYMBOL(__dev_queue_xmit); 4683 4684 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4685 { 4686 struct net_device *dev = skb->dev; 4687 struct sk_buff *orig_skb = skb; 4688 struct netdev_queue *txq; 4689 int ret = NETDEV_TX_BUSY; 4690 bool again = false; 4691 4692 if (unlikely(!netif_running(dev) || 4693 !netif_carrier_ok(dev))) 4694 goto drop; 4695 4696 skb = validate_xmit_skb_list(skb, dev, &again); 4697 if (skb != orig_skb) 4698 goto drop; 4699 4700 skb_set_queue_mapping(skb, queue_id); 4701 txq = skb_get_tx_queue(dev, skb); 4702 4703 local_bh_disable(); 4704 4705 dev_xmit_recursion_inc(); 4706 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4707 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4708 ret = netdev_start_xmit(skb, dev, txq, false); 4709 HARD_TX_UNLOCK(dev, txq); 4710 dev_xmit_recursion_dec(); 4711 4712 local_bh_enable(); 4713 return ret; 4714 drop: 4715 dev_core_stats_tx_dropped_inc(dev); 4716 kfree_skb_list(skb); 4717 return NET_XMIT_DROP; 4718 } 4719 EXPORT_SYMBOL(__dev_direct_xmit); 4720 4721 /************************************************************************* 4722 * Receiver routines 4723 *************************************************************************/ 4724 static DEFINE_PER_CPU(struct task_struct *, backlog_napi); 4725 4726 int weight_p __read_mostly = 64; /* old backlog weight */ 4727 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4728 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4729 4730 /* Called with irq disabled */ 4731 static inline void ____napi_schedule(struct softnet_data *sd, 4732 struct napi_struct *napi) 4733 { 4734 struct task_struct *thread; 4735 4736 lockdep_assert_irqs_disabled(); 4737 4738 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4739 /* Paired with smp_mb__before_atomic() in 4740 * napi_enable()/dev_set_threaded(). 4741 * Use READ_ONCE() to guarantee a complete 4742 * read on napi->thread. Only call 4743 * wake_up_process() when it's not NULL. 4744 */ 4745 thread = READ_ONCE(napi->thread); 4746 if (thread) { 4747 if (use_backlog_threads() && thread == raw_cpu_read(backlog_napi)) 4748 goto use_local_napi; 4749 4750 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4751 wake_up_process(thread); 4752 return; 4753 } 4754 } 4755 4756 use_local_napi: 4757 list_add_tail(&napi->poll_list, &sd->poll_list); 4758 WRITE_ONCE(napi->list_owner, smp_processor_id()); 4759 /* If not called from net_rx_action() 4760 * we have to raise NET_RX_SOFTIRQ. 4761 */ 4762 if (!sd->in_net_rx_action) 4763 raise_softirq_irqoff(NET_RX_SOFTIRQ); 4764 } 4765 4766 #ifdef CONFIG_RPS 4767 4768 struct static_key_false rps_needed __read_mostly; 4769 EXPORT_SYMBOL(rps_needed); 4770 struct static_key_false rfs_needed __read_mostly; 4771 EXPORT_SYMBOL(rfs_needed); 4772 4773 static struct rps_dev_flow * 4774 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4775 struct rps_dev_flow *rflow, u16 next_cpu) 4776 { 4777 if (next_cpu < nr_cpu_ids) { 4778 u32 head; 4779 #ifdef CONFIG_RFS_ACCEL 4780 struct netdev_rx_queue *rxqueue; 4781 struct rps_dev_flow_table *flow_table; 4782 struct rps_dev_flow *old_rflow; 4783 u16 rxq_index; 4784 u32 flow_id; 4785 int rc; 4786 4787 /* Should we steer this flow to a different hardware queue? */ 4788 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4789 !(dev->features & NETIF_F_NTUPLE)) 4790 goto out; 4791 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4792 if (rxq_index == skb_get_rx_queue(skb)) 4793 goto out; 4794 4795 rxqueue = dev->_rx + rxq_index; 4796 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4797 if (!flow_table) 4798 goto out; 4799 flow_id = skb_get_hash(skb) & flow_table->mask; 4800 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4801 rxq_index, flow_id); 4802 if (rc < 0) 4803 goto out; 4804 old_rflow = rflow; 4805 rflow = &flow_table->flows[flow_id]; 4806 WRITE_ONCE(rflow->filter, rc); 4807 if (old_rflow->filter == rc) 4808 WRITE_ONCE(old_rflow->filter, RPS_NO_FILTER); 4809 out: 4810 #endif 4811 head = READ_ONCE(per_cpu(softnet_data, next_cpu).input_queue_head); 4812 rps_input_queue_tail_save(&rflow->last_qtail, head); 4813 } 4814 4815 WRITE_ONCE(rflow->cpu, next_cpu); 4816 return rflow; 4817 } 4818 4819 /* 4820 * get_rps_cpu is called from netif_receive_skb and returns the target 4821 * CPU from the RPS map of the receiving queue for a given skb. 4822 * rcu_read_lock must be held on entry. 4823 */ 4824 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4825 struct rps_dev_flow **rflowp) 4826 { 4827 const struct rps_sock_flow_table *sock_flow_table; 4828 struct netdev_rx_queue *rxqueue = dev->_rx; 4829 struct rps_dev_flow_table *flow_table; 4830 struct rps_map *map; 4831 int cpu = -1; 4832 u32 tcpu; 4833 u32 hash; 4834 4835 if (skb_rx_queue_recorded(skb)) { 4836 u16 index = skb_get_rx_queue(skb); 4837 4838 if (unlikely(index >= dev->real_num_rx_queues)) { 4839 WARN_ONCE(dev->real_num_rx_queues > 1, 4840 "%s received packet on queue %u, but number " 4841 "of RX queues is %u\n", 4842 dev->name, index, dev->real_num_rx_queues); 4843 goto done; 4844 } 4845 rxqueue += index; 4846 } 4847 4848 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4849 4850 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4851 map = rcu_dereference(rxqueue->rps_map); 4852 if (!flow_table && !map) 4853 goto done; 4854 4855 skb_reset_network_header(skb); 4856 hash = skb_get_hash(skb); 4857 if (!hash) 4858 goto done; 4859 4860 sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table); 4861 if (flow_table && sock_flow_table) { 4862 struct rps_dev_flow *rflow; 4863 u32 next_cpu; 4864 u32 ident; 4865 4866 /* First check into global flow table if there is a match. 4867 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow(). 4868 */ 4869 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]); 4870 if ((ident ^ hash) & ~net_hotdata.rps_cpu_mask) 4871 goto try_rps; 4872 4873 next_cpu = ident & net_hotdata.rps_cpu_mask; 4874 4875 /* OK, now we know there is a match, 4876 * we can look at the local (per receive queue) flow table 4877 */ 4878 rflow = &flow_table->flows[hash & flow_table->mask]; 4879 tcpu = rflow->cpu; 4880 4881 /* 4882 * If the desired CPU (where last recvmsg was done) is 4883 * different from current CPU (one in the rx-queue flow 4884 * table entry), switch if one of the following holds: 4885 * - Current CPU is unset (>= nr_cpu_ids). 4886 * - Current CPU is offline. 4887 * - The current CPU's queue tail has advanced beyond the 4888 * last packet that was enqueued using this table entry. 4889 * This guarantees that all previous packets for the flow 4890 * have been dequeued, thus preserving in order delivery. 4891 */ 4892 if (unlikely(tcpu != next_cpu) && 4893 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4894 ((int)(READ_ONCE(per_cpu(softnet_data, tcpu).input_queue_head) - 4895 rflow->last_qtail)) >= 0)) { 4896 tcpu = next_cpu; 4897 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4898 } 4899 4900 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4901 *rflowp = rflow; 4902 cpu = tcpu; 4903 goto done; 4904 } 4905 } 4906 4907 try_rps: 4908 4909 if (map) { 4910 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4911 if (cpu_online(tcpu)) { 4912 cpu = tcpu; 4913 goto done; 4914 } 4915 } 4916 4917 done: 4918 return cpu; 4919 } 4920 4921 #ifdef CONFIG_RFS_ACCEL 4922 4923 /** 4924 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4925 * @dev: Device on which the filter was set 4926 * @rxq_index: RX queue index 4927 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4928 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4929 * 4930 * Drivers that implement ndo_rx_flow_steer() should periodically call 4931 * this function for each installed filter and remove the filters for 4932 * which it returns %true. 4933 */ 4934 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4935 u32 flow_id, u16 filter_id) 4936 { 4937 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4938 struct rps_dev_flow_table *flow_table; 4939 struct rps_dev_flow *rflow; 4940 bool expire = true; 4941 unsigned int cpu; 4942 4943 rcu_read_lock(); 4944 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4945 if (flow_table && flow_id <= flow_table->mask) { 4946 rflow = &flow_table->flows[flow_id]; 4947 cpu = READ_ONCE(rflow->cpu); 4948 if (READ_ONCE(rflow->filter) == filter_id && cpu < nr_cpu_ids && 4949 ((int)(READ_ONCE(per_cpu(softnet_data, cpu).input_queue_head) - 4950 READ_ONCE(rflow->last_qtail)) < 4951 (int)(10 * flow_table->mask))) 4952 expire = false; 4953 } 4954 rcu_read_unlock(); 4955 return expire; 4956 } 4957 EXPORT_SYMBOL(rps_may_expire_flow); 4958 4959 #endif /* CONFIG_RFS_ACCEL */ 4960 4961 /* Called from hardirq (IPI) context */ 4962 static void rps_trigger_softirq(void *data) 4963 { 4964 struct softnet_data *sd = data; 4965 4966 ____napi_schedule(sd, &sd->backlog); 4967 sd->received_rps++; 4968 } 4969 4970 #endif /* CONFIG_RPS */ 4971 4972 /* Called from hardirq (IPI) context */ 4973 static void trigger_rx_softirq(void *data) 4974 { 4975 struct softnet_data *sd = data; 4976 4977 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4978 smp_store_release(&sd->defer_ipi_scheduled, 0); 4979 } 4980 4981 /* 4982 * After we queued a packet into sd->input_pkt_queue, 4983 * we need to make sure this queue is serviced soon. 4984 * 4985 * - If this is another cpu queue, link it to our rps_ipi_list, 4986 * and make sure we will process rps_ipi_list from net_rx_action(). 4987 * 4988 * - If this is our own queue, NAPI schedule our backlog. 4989 * Note that this also raises NET_RX_SOFTIRQ. 4990 */ 4991 static void napi_schedule_rps(struct softnet_data *sd) 4992 { 4993 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4994 4995 #ifdef CONFIG_RPS 4996 if (sd != mysd) { 4997 if (use_backlog_threads()) { 4998 __napi_schedule_irqoff(&sd->backlog); 4999 return; 5000 } 5001 5002 sd->rps_ipi_next = mysd->rps_ipi_list; 5003 mysd->rps_ipi_list = sd; 5004 5005 /* If not called from net_rx_action() or napi_threaded_poll() 5006 * we have to raise NET_RX_SOFTIRQ. 5007 */ 5008 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll) 5009 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 5010 return; 5011 } 5012 #endif /* CONFIG_RPS */ 5013 __napi_schedule_irqoff(&mysd->backlog); 5014 } 5015 5016 void kick_defer_list_purge(struct softnet_data *sd, unsigned int cpu) 5017 { 5018 unsigned long flags; 5019 5020 if (use_backlog_threads()) { 5021 backlog_lock_irq_save(sd, &flags); 5022 5023 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 5024 __napi_schedule_irqoff(&sd->backlog); 5025 5026 backlog_unlock_irq_restore(sd, &flags); 5027 5028 } else if (!cmpxchg(&sd->defer_ipi_scheduled, 0, 1)) { 5029 smp_call_function_single_async(cpu, &sd->defer_csd); 5030 } 5031 } 5032 5033 #ifdef CONFIG_NET_FLOW_LIMIT 5034 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 5035 #endif 5036 5037 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 5038 { 5039 #ifdef CONFIG_NET_FLOW_LIMIT 5040 struct sd_flow_limit *fl; 5041 struct softnet_data *sd; 5042 unsigned int old_flow, new_flow; 5043 5044 if (qlen < (READ_ONCE(net_hotdata.max_backlog) >> 1)) 5045 return false; 5046 5047 sd = this_cpu_ptr(&softnet_data); 5048 5049 rcu_read_lock(); 5050 fl = rcu_dereference(sd->flow_limit); 5051 if (fl) { 5052 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 5053 old_flow = fl->history[fl->history_head]; 5054 fl->history[fl->history_head] = new_flow; 5055 5056 fl->history_head++; 5057 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 5058 5059 if (likely(fl->buckets[old_flow])) 5060 fl->buckets[old_flow]--; 5061 5062 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 5063 fl->count++; 5064 rcu_read_unlock(); 5065 return true; 5066 } 5067 } 5068 rcu_read_unlock(); 5069 #endif 5070 return false; 5071 } 5072 5073 /* 5074 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 5075 * queue (may be a remote CPU queue). 5076 */ 5077 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 5078 unsigned int *qtail) 5079 { 5080 enum skb_drop_reason reason; 5081 struct softnet_data *sd; 5082 unsigned long flags; 5083 unsigned int qlen; 5084 int max_backlog; 5085 u32 tail; 5086 5087 reason = SKB_DROP_REASON_DEV_READY; 5088 if (!netif_running(skb->dev)) 5089 goto bad_dev; 5090 5091 reason = SKB_DROP_REASON_CPU_BACKLOG; 5092 sd = &per_cpu(softnet_data, cpu); 5093 5094 qlen = skb_queue_len_lockless(&sd->input_pkt_queue); 5095 max_backlog = READ_ONCE(net_hotdata.max_backlog); 5096 if (unlikely(qlen > max_backlog)) 5097 goto cpu_backlog_drop; 5098 backlog_lock_irq_save(sd, &flags); 5099 qlen = skb_queue_len(&sd->input_pkt_queue); 5100 if (qlen <= max_backlog && !skb_flow_limit(skb, qlen)) { 5101 if (!qlen) { 5102 /* Schedule NAPI for backlog device. We can use 5103 * non atomic operation as we own the queue lock. 5104 */ 5105 if (!__test_and_set_bit(NAPI_STATE_SCHED, 5106 &sd->backlog.state)) 5107 napi_schedule_rps(sd); 5108 } 5109 __skb_queue_tail(&sd->input_pkt_queue, skb); 5110 tail = rps_input_queue_tail_incr(sd); 5111 backlog_unlock_irq_restore(sd, &flags); 5112 5113 /* save the tail outside of the critical section */ 5114 rps_input_queue_tail_save(qtail, tail); 5115 return NET_RX_SUCCESS; 5116 } 5117 5118 backlog_unlock_irq_restore(sd, &flags); 5119 5120 cpu_backlog_drop: 5121 atomic_inc(&sd->dropped); 5122 bad_dev: 5123 dev_core_stats_rx_dropped_inc(skb->dev); 5124 kfree_skb_reason(skb, reason); 5125 return NET_RX_DROP; 5126 } 5127 5128 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 5129 { 5130 struct net_device *dev = skb->dev; 5131 struct netdev_rx_queue *rxqueue; 5132 5133 rxqueue = dev->_rx; 5134 5135 if (skb_rx_queue_recorded(skb)) { 5136 u16 index = skb_get_rx_queue(skb); 5137 5138 if (unlikely(index >= dev->real_num_rx_queues)) { 5139 WARN_ONCE(dev->real_num_rx_queues > 1, 5140 "%s received packet on queue %u, but number " 5141 "of RX queues is %u\n", 5142 dev->name, index, dev->real_num_rx_queues); 5143 5144 return rxqueue; /* Return first rxqueue */ 5145 } 5146 rxqueue += index; 5147 } 5148 return rxqueue; 5149 } 5150 5151 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 5152 const struct bpf_prog *xdp_prog) 5153 { 5154 void *orig_data, *orig_data_end, *hard_start; 5155 struct netdev_rx_queue *rxqueue; 5156 bool orig_bcast, orig_host; 5157 u32 mac_len, frame_sz; 5158 __be16 orig_eth_type; 5159 struct ethhdr *eth; 5160 u32 metalen, act; 5161 int off; 5162 5163 /* The XDP program wants to see the packet starting at the MAC 5164 * header. 5165 */ 5166 mac_len = skb->data - skb_mac_header(skb); 5167 hard_start = skb->data - skb_headroom(skb); 5168 5169 /* SKB "head" area always have tailroom for skb_shared_info */ 5170 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 5171 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 5172 5173 rxqueue = netif_get_rxqueue(skb); 5174 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 5175 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 5176 skb_headlen(skb) + mac_len, true); 5177 if (skb_is_nonlinear(skb)) { 5178 skb_shinfo(skb)->xdp_frags_size = skb->data_len; 5179 xdp_buff_set_frags_flag(xdp); 5180 } else { 5181 xdp_buff_clear_frags_flag(xdp); 5182 } 5183 5184 orig_data_end = xdp->data_end; 5185 orig_data = xdp->data; 5186 eth = (struct ethhdr *)xdp->data; 5187 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 5188 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 5189 orig_eth_type = eth->h_proto; 5190 5191 act = bpf_prog_run_xdp(xdp_prog, xdp); 5192 5193 /* check if bpf_xdp_adjust_head was used */ 5194 off = xdp->data - orig_data; 5195 if (off) { 5196 if (off > 0) 5197 __skb_pull(skb, off); 5198 else if (off < 0) 5199 __skb_push(skb, -off); 5200 5201 skb->mac_header += off; 5202 skb_reset_network_header(skb); 5203 } 5204 5205 /* check if bpf_xdp_adjust_tail was used */ 5206 off = xdp->data_end - orig_data_end; 5207 if (off != 0) { 5208 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 5209 skb->len += off; /* positive on grow, negative on shrink */ 5210 } 5211 5212 /* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers 5213 * (e.g. bpf_xdp_adjust_tail), we need to update data_len here. 5214 */ 5215 if (xdp_buff_has_frags(xdp)) 5216 skb->data_len = skb_shinfo(skb)->xdp_frags_size; 5217 else 5218 skb->data_len = 0; 5219 5220 /* check if XDP changed eth hdr such SKB needs update */ 5221 eth = (struct ethhdr *)xdp->data; 5222 if ((orig_eth_type != eth->h_proto) || 5223 (orig_host != ether_addr_equal_64bits(eth->h_dest, 5224 skb->dev->dev_addr)) || 5225 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 5226 __skb_push(skb, ETH_HLEN); 5227 skb->pkt_type = PACKET_HOST; 5228 skb->protocol = eth_type_trans(skb, skb->dev); 5229 } 5230 5231 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 5232 * before calling us again on redirect path. We do not call do_redirect 5233 * as we leave that up to the caller. 5234 * 5235 * Caller is responsible for managing lifetime of skb (i.e. calling 5236 * kfree_skb in response to actions it cannot handle/XDP_DROP). 5237 */ 5238 switch (act) { 5239 case XDP_REDIRECT: 5240 case XDP_TX: 5241 __skb_push(skb, mac_len); 5242 break; 5243 case XDP_PASS: 5244 metalen = xdp->data - xdp->data_meta; 5245 if (metalen) 5246 skb_metadata_set(skb, metalen); 5247 break; 5248 } 5249 5250 return act; 5251 } 5252 5253 static int 5254 netif_skb_check_for_xdp(struct sk_buff **pskb, const struct bpf_prog *prog) 5255 { 5256 struct sk_buff *skb = *pskb; 5257 int err, hroom, troom; 5258 5259 if (!skb_cow_data_for_xdp(this_cpu_read(system_page_pool), pskb, prog)) 5260 return 0; 5261 5262 /* In case we have to go down the path and also linearize, 5263 * then lets do the pskb_expand_head() work just once here. 5264 */ 5265 hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 5266 troom = skb->tail + skb->data_len - skb->end; 5267 err = pskb_expand_head(skb, 5268 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 5269 troom > 0 ? troom + 128 : 0, GFP_ATOMIC); 5270 if (err) 5271 return err; 5272 5273 return skb_linearize(skb); 5274 } 5275 5276 static u32 netif_receive_generic_xdp(struct sk_buff **pskb, 5277 struct xdp_buff *xdp, 5278 const struct bpf_prog *xdp_prog) 5279 { 5280 struct sk_buff *skb = *pskb; 5281 u32 mac_len, act = XDP_DROP; 5282 5283 /* Reinjected packets coming from act_mirred or similar should 5284 * not get XDP generic processing. 5285 */ 5286 if (skb_is_redirected(skb)) 5287 return XDP_PASS; 5288 5289 /* XDP packets must have sufficient headroom of XDP_PACKET_HEADROOM 5290 * bytes. This is the guarantee that also native XDP provides, 5291 * thus we need to do it here as well. 5292 */ 5293 mac_len = skb->data - skb_mac_header(skb); 5294 __skb_push(skb, mac_len); 5295 5296 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 5297 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 5298 if (netif_skb_check_for_xdp(pskb, xdp_prog)) 5299 goto do_drop; 5300 } 5301 5302 __skb_pull(*pskb, mac_len); 5303 5304 act = bpf_prog_run_generic_xdp(*pskb, xdp, xdp_prog); 5305 switch (act) { 5306 case XDP_REDIRECT: 5307 case XDP_TX: 5308 case XDP_PASS: 5309 break; 5310 default: 5311 bpf_warn_invalid_xdp_action((*pskb)->dev, xdp_prog, act); 5312 fallthrough; 5313 case XDP_ABORTED: 5314 trace_xdp_exception((*pskb)->dev, xdp_prog, act); 5315 fallthrough; 5316 case XDP_DROP: 5317 do_drop: 5318 kfree_skb(*pskb); 5319 break; 5320 } 5321 5322 return act; 5323 } 5324 5325 /* When doing generic XDP we have to bypass the qdisc layer and the 5326 * network taps in order to match in-driver-XDP behavior. This also means 5327 * that XDP packets are able to starve other packets going through a qdisc, 5328 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 5329 * queues, so they do not have this starvation issue. 5330 */ 5331 void generic_xdp_tx(struct sk_buff *skb, const struct bpf_prog *xdp_prog) 5332 { 5333 struct net_device *dev = skb->dev; 5334 struct netdev_queue *txq; 5335 bool free_skb = true; 5336 int cpu, rc; 5337 5338 txq = netdev_core_pick_tx(dev, skb, NULL); 5339 cpu = smp_processor_id(); 5340 HARD_TX_LOCK(dev, txq, cpu); 5341 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 5342 rc = netdev_start_xmit(skb, dev, txq, 0); 5343 if (dev_xmit_complete(rc)) 5344 free_skb = false; 5345 } 5346 HARD_TX_UNLOCK(dev, txq); 5347 if (free_skb) { 5348 trace_xdp_exception(dev, xdp_prog, XDP_TX); 5349 dev_core_stats_tx_dropped_inc(dev); 5350 kfree_skb(skb); 5351 } 5352 } 5353 5354 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 5355 5356 int do_xdp_generic(const struct bpf_prog *xdp_prog, struct sk_buff **pskb) 5357 { 5358 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 5359 5360 if (xdp_prog) { 5361 struct xdp_buff xdp; 5362 u32 act; 5363 int err; 5364 5365 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 5366 act = netif_receive_generic_xdp(pskb, &xdp, xdp_prog); 5367 if (act != XDP_PASS) { 5368 switch (act) { 5369 case XDP_REDIRECT: 5370 err = xdp_do_generic_redirect((*pskb)->dev, *pskb, 5371 &xdp, xdp_prog); 5372 if (err) 5373 goto out_redir; 5374 break; 5375 case XDP_TX: 5376 generic_xdp_tx(*pskb, xdp_prog); 5377 break; 5378 } 5379 bpf_net_ctx_clear(bpf_net_ctx); 5380 return XDP_DROP; 5381 } 5382 bpf_net_ctx_clear(bpf_net_ctx); 5383 } 5384 return XDP_PASS; 5385 out_redir: 5386 bpf_net_ctx_clear(bpf_net_ctx); 5387 kfree_skb_reason(*pskb, SKB_DROP_REASON_XDP); 5388 return XDP_DROP; 5389 } 5390 EXPORT_SYMBOL_GPL(do_xdp_generic); 5391 5392 static int netif_rx_internal(struct sk_buff *skb) 5393 { 5394 int ret; 5395 5396 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5397 5398 trace_netif_rx(skb); 5399 5400 #ifdef CONFIG_RPS 5401 if (static_branch_unlikely(&rps_needed)) { 5402 struct rps_dev_flow voidflow, *rflow = &voidflow; 5403 int cpu; 5404 5405 rcu_read_lock(); 5406 5407 cpu = get_rps_cpu(skb->dev, skb, &rflow); 5408 if (cpu < 0) 5409 cpu = smp_processor_id(); 5410 5411 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5412 5413 rcu_read_unlock(); 5414 } else 5415 #endif 5416 { 5417 unsigned int qtail; 5418 5419 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 5420 } 5421 return ret; 5422 } 5423 5424 /** 5425 * __netif_rx - Slightly optimized version of netif_rx 5426 * @skb: buffer to post 5427 * 5428 * This behaves as netif_rx except that it does not disable bottom halves. 5429 * As a result this function may only be invoked from the interrupt context 5430 * (either hard or soft interrupt). 5431 */ 5432 int __netif_rx(struct sk_buff *skb) 5433 { 5434 int ret; 5435 5436 lockdep_assert_once(hardirq_count() | softirq_count()); 5437 5438 trace_netif_rx_entry(skb); 5439 ret = netif_rx_internal(skb); 5440 trace_netif_rx_exit(ret); 5441 return ret; 5442 } 5443 EXPORT_SYMBOL(__netif_rx); 5444 5445 /** 5446 * netif_rx - post buffer to the network code 5447 * @skb: buffer to post 5448 * 5449 * This function receives a packet from a device driver and queues it for 5450 * the upper (protocol) levels to process via the backlog NAPI device. It 5451 * always succeeds. The buffer may be dropped during processing for 5452 * congestion control or by the protocol layers. 5453 * The network buffer is passed via the backlog NAPI device. Modern NIC 5454 * driver should use NAPI and GRO. 5455 * This function can used from interrupt and from process context. The 5456 * caller from process context must not disable interrupts before invoking 5457 * this function. 5458 * 5459 * return values: 5460 * NET_RX_SUCCESS (no congestion) 5461 * NET_RX_DROP (packet was dropped) 5462 * 5463 */ 5464 int netif_rx(struct sk_buff *skb) 5465 { 5466 bool need_bh_off = !(hardirq_count() | softirq_count()); 5467 int ret; 5468 5469 if (need_bh_off) 5470 local_bh_disable(); 5471 trace_netif_rx_entry(skb); 5472 ret = netif_rx_internal(skb); 5473 trace_netif_rx_exit(ret); 5474 if (need_bh_off) 5475 local_bh_enable(); 5476 return ret; 5477 } 5478 EXPORT_SYMBOL(netif_rx); 5479 5480 static __latent_entropy void net_tx_action(void) 5481 { 5482 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5483 5484 if (sd->completion_queue) { 5485 struct sk_buff *clist; 5486 5487 local_irq_disable(); 5488 clist = sd->completion_queue; 5489 sd->completion_queue = NULL; 5490 local_irq_enable(); 5491 5492 while (clist) { 5493 struct sk_buff *skb = clist; 5494 5495 clist = clist->next; 5496 5497 WARN_ON(refcount_read(&skb->users)); 5498 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED)) 5499 trace_consume_skb(skb, net_tx_action); 5500 else 5501 trace_kfree_skb(skb, net_tx_action, 5502 get_kfree_skb_cb(skb)->reason, NULL); 5503 5504 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5505 __kfree_skb(skb); 5506 else 5507 __napi_kfree_skb(skb, 5508 get_kfree_skb_cb(skb)->reason); 5509 } 5510 } 5511 5512 if (sd->output_queue) { 5513 struct Qdisc *head; 5514 5515 local_irq_disable(); 5516 head = sd->output_queue; 5517 sd->output_queue = NULL; 5518 sd->output_queue_tailp = &sd->output_queue; 5519 local_irq_enable(); 5520 5521 rcu_read_lock(); 5522 5523 while (head) { 5524 struct Qdisc *q = head; 5525 spinlock_t *root_lock = NULL; 5526 5527 head = head->next_sched; 5528 5529 /* We need to make sure head->next_sched is read 5530 * before clearing __QDISC_STATE_SCHED 5531 */ 5532 smp_mb__before_atomic(); 5533 5534 if (!(q->flags & TCQ_F_NOLOCK)) { 5535 root_lock = qdisc_lock(q); 5536 spin_lock(root_lock); 5537 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5538 &q->state))) { 5539 /* There is a synchronize_net() between 5540 * STATE_DEACTIVATED flag being set and 5541 * qdisc_reset()/some_qdisc_is_busy() in 5542 * dev_deactivate(), so we can safely bail out 5543 * early here to avoid data race between 5544 * qdisc_deactivate() and some_qdisc_is_busy() 5545 * for lockless qdisc. 5546 */ 5547 clear_bit(__QDISC_STATE_SCHED, &q->state); 5548 continue; 5549 } 5550 5551 clear_bit(__QDISC_STATE_SCHED, &q->state); 5552 qdisc_run(q); 5553 if (root_lock) 5554 spin_unlock(root_lock); 5555 } 5556 5557 rcu_read_unlock(); 5558 } 5559 5560 xfrm_dev_backlog(sd); 5561 } 5562 5563 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5564 /* This hook is defined here for ATM LANE */ 5565 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5566 unsigned char *addr) __read_mostly; 5567 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5568 #endif 5569 5570 /** 5571 * netdev_is_rx_handler_busy - check if receive handler is registered 5572 * @dev: device to check 5573 * 5574 * Check if a receive handler is already registered for a given device. 5575 * Return true if there one. 5576 * 5577 * The caller must hold the rtnl_mutex. 5578 */ 5579 bool netdev_is_rx_handler_busy(struct net_device *dev) 5580 { 5581 ASSERT_RTNL(); 5582 return dev && rtnl_dereference(dev->rx_handler); 5583 } 5584 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5585 5586 /** 5587 * netdev_rx_handler_register - register receive handler 5588 * @dev: device to register a handler for 5589 * @rx_handler: receive handler to register 5590 * @rx_handler_data: data pointer that is used by rx handler 5591 * 5592 * Register a receive handler for a device. This handler will then be 5593 * called from __netif_receive_skb. A negative errno code is returned 5594 * on a failure. 5595 * 5596 * The caller must hold the rtnl_mutex. 5597 * 5598 * For a general description of rx_handler, see enum rx_handler_result. 5599 */ 5600 int netdev_rx_handler_register(struct net_device *dev, 5601 rx_handler_func_t *rx_handler, 5602 void *rx_handler_data) 5603 { 5604 if (netdev_is_rx_handler_busy(dev)) 5605 return -EBUSY; 5606 5607 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5608 return -EINVAL; 5609 5610 /* Note: rx_handler_data must be set before rx_handler */ 5611 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5612 rcu_assign_pointer(dev->rx_handler, rx_handler); 5613 5614 return 0; 5615 } 5616 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5617 5618 /** 5619 * netdev_rx_handler_unregister - unregister receive handler 5620 * @dev: device to unregister a handler from 5621 * 5622 * Unregister a receive handler from a device. 5623 * 5624 * The caller must hold the rtnl_mutex. 5625 */ 5626 void netdev_rx_handler_unregister(struct net_device *dev) 5627 { 5628 5629 ASSERT_RTNL(); 5630 RCU_INIT_POINTER(dev->rx_handler, NULL); 5631 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5632 * section has a guarantee to see a non NULL rx_handler_data 5633 * as well. 5634 */ 5635 synchronize_net(); 5636 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5637 } 5638 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5639 5640 /* 5641 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5642 * the special handling of PFMEMALLOC skbs. 5643 */ 5644 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5645 { 5646 switch (skb->protocol) { 5647 case htons(ETH_P_ARP): 5648 case htons(ETH_P_IP): 5649 case htons(ETH_P_IPV6): 5650 case htons(ETH_P_8021Q): 5651 case htons(ETH_P_8021AD): 5652 return true; 5653 default: 5654 return false; 5655 } 5656 } 5657 5658 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5659 int *ret, struct net_device *orig_dev) 5660 { 5661 if (nf_hook_ingress_active(skb)) { 5662 int ingress_retval; 5663 5664 if (*pt_prev) { 5665 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5666 *pt_prev = NULL; 5667 } 5668 5669 rcu_read_lock(); 5670 ingress_retval = nf_hook_ingress(skb); 5671 rcu_read_unlock(); 5672 return ingress_retval; 5673 } 5674 return 0; 5675 } 5676 5677 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5678 struct packet_type **ppt_prev) 5679 { 5680 struct packet_type *ptype, *pt_prev; 5681 rx_handler_func_t *rx_handler; 5682 struct sk_buff *skb = *pskb; 5683 struct net_device *orig_dev; 5684 bool deliver_exact = false; 5685 int ret = NET_RX_DROP; 5686 __be16 type; 5687 5688 net_timestamp_check(!READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5689 5690 trace_netif_receive_skb(skb); 5691 5692 orig_dev = skb->dev; 5693 5694 skb_reset_network_header(skb); 5695 #if !defined(CONFIG_DEBUG_NET) 5696 /* We plan to no longer reset the transport header here. 5697 * Give some time to fuzzers and dev build to catch bugs 5698 * in network stacks. 5699 */ 5700 if (!skb_transport_header_was_set(skb)) 5701 skb_reset_transport_header(skb); 5702 #endif 5703 skb_reset_mac_len(skb); 5704 5705 pt_prev = NULL; 5706 5707 another_round: 5708 skb->skb_iif = skb->dev->ifindex; 5709 5710 __this_cpu_inc(softnet_data.processed); 5711 5712 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5713 int ret2; 5714 5715 migrate_disable(); 5716 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), 5717 &skb); 5718 migrate_enable(); 5719 5720 if (ret2 != XDP_PASS) { 5721 ret = NET_RX_DROP; 5722 goto out; 5723 } 5724 } 5725 5726 if (eth_type_vlan(skb->protocol)) { 5727 skb = skb_vlan_untag(skb); 5728 if (unlikely(!skb)) 5729 goto out; 5730 } 5731 5732 if (skb_skip_tc_classify(skb)) 5733 goto skip_classify; 5734 5735 if (pfmemalloc) 5736 goto skip_taps; 5737 5738 list_for_each_entry_rcu(ptype, &net_hotdata.ptype_all, list) { 5739 if (pt_prev) 5740 ret = deliver_skb(skb, pt_prev, orig_dev); 5741 pt_prev = ptype; 5742 } 5743 5744 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5745 if (pt_prev) 5746 ret = deliver_skb(skb, pt_prev, orig_dev); 5747 pt_prev = ptype; 5748 } 5749 5750 skip_taps: 5751 #ifdef CONFIG_NET_INGRESS 5752 if (static_branch_unlikely(&ingress_needed_key)) { 5753 bool another = false; 5754 5755 nf_skip_egress(skb, true); 5756 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5757 &another); 5758 if (another) 5759 goto another_round; 5760 if (!skb) 5761 goto out; 5762 5763 nf_skip_egress(skb, false); 5764 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5765 goto out; 5766 } 5767 #endif 5768 skb_reset_redirect(skb); 5769 skip_classify: 5770 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5771 goto drop; 5772 5773 if (skb_vlan_tag_present(skb)) { 5774 if (pt_prev) { 5775 ret = deliver_skb(skb, pt_prev, orig_dev); 5776 pt_prev = NULL; 5777 } 5778 if (vlan_do_receive(&skb)) 5779 goto another_round; 5780 else if (unlikely(!skb)) 5781 goto out; 5782 } 5783 5784 rx_handler = rcu_dereference(skb->dev->rx_handler); 5785 if (rx_handler) { 5786 if (pt_prev) { 5787 ret = deliver_skb(skb, pt_prev, orig_dev); 5788 pt_prev = NULL; 5789 } 5790 switch (rx_handler(&skb)) { 5791 case RX_HANDLER_CONSUMED: 5792 ret = NET_RX_SUCCESS; 5793 goto out; 5794 case RX_HANDLER_ANOTHER: 5795 goto another_round; 5796 case RX_HANDLER_EXACT: 5797 deliver_exact = true; 5798 break; 5799 case RX_HANDLER_PASS: 5800 break; 5801 default: 5802 BUG(); 5803 } 5804 } 5805 5806 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5807 check_vlan_id: 5808 if (skb_vlan_tag_get_id(skb)) { 5809 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5810 * find vlan device. 5811 */ 5812 skb->pkt_type = PACKET_OTHERHOST; 5813 } else if (eth_type_vlan(skb->protocol)) { 5814 /* Outer header is 802.1P with vlan 0, inner header is 5815 * 802.1Q or 802.1AD and vlan_do_receive() above could 5816 * not find vlan dev for vlan id 0. 5817 */ 5818 __vlan_hwaccel_clear_tag(skb); 5819 skb = skb_vlan_untag(skb); 5820 if (unlikely(!skb)) 5821 goto out; 5822 if (vlan_do_receive(&skb)) 5823 /* After stripping off 802.1P header with vlan 0 5824 * vlan dev is found for inner header. 5825 */ 5826 goto another_round; 5827 else if (unlikely(!skb)) 5828 goto out; 5829 else 5830 /* We have stripped outer 802.1P vlan 0 header. 5831 * But could not find vlan dev. 5832 * check again for vlan id to set OTHERHOST. 5833 */ 5834 goto check_vlan_id; 5835 } 5836 /* Note: we might in the future use prio bits 5837 * and set skb->priority like in vlan_do_receive() 5838 * For the time being, just ignore Priority Code Point 5839 */ 5840 __vlan_hwaccel_clear_tag(skb); 5841 } 5842 5843 type = skb->protocol; 5844 5845 /* deliver only exact match when indicated */ 5846 if (likely(!deliver_exact)) { 5847 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5848 &ptype_base[ntohs(type) & 5849 PTYPE_HASH_MASK]); 5850 } 5851 5852 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5853 &orig_dev->ptype_specific); 5854 5855 if (unlikely(skb->dev != orig_dev)) { 5856 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5857 &skb->dev->ptype_specific); 5858 } 5859 5860 if (pt_prev) { 5861 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5862 goto drop; 5863 *ppt_prev = pt_prev; 5864 } else { 5865 drop: 5866 if (!deliver_exact) 5867 dev_core_stats_rx_dropped_inc(skb->dev); 5868 else 5869 dev_core_stats_rx_nohandler_inc(skb->dev); 5870 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5871 /* Jamal, now you will not able to escape explaining 5872 * me how you were going to use this. :-) 5873 */ 5874 ret = NET_RX_DROP; 5875 } 5876 5877 out: 5878 /* The invariant here is that if *ppt_prev is not NULL 5879 * then skb should also be non-NULL. 5880 * 5881 * Apparently *ppt_prev assignment above holds this invariant due to 5882 * skb dereferencing near it. 5883 */ 5884 *pskb = skb; 5885 return ret; 5886 } 5887 5888 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5889 { 5890 struct net_device *orig_dev = skb->dev; 5891 struct packet_type *pt_prev = NULL; 5892 int ret; 5893 5894 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5895 if (pt_prev) 5896 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5897 skb->dev, pt_prev, orig_dev); 5898 return ret; 5899 } 5900 5901 /** 5902 * netif_receive_skb_core - special purpose version of netif_receive_skb 5903 * @skb: buffer to process 5904 * 5905 * More direct receive version of netif_receive_skb(). It should 5906 * only be used by callers that have a need to skip RPS and Generic XDP. 5907 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5908 * 5909 * This function may only be called from softirq context and interrupts 5910 * should be enabled. 5911 * 5912 * Return values (usually ignored): 5913 * NET_RX_SUCCESS: no congestion 5914 * NET_RX_DROP: packet was dropped 5915 */ 5916 int netif_receive_skb_core(struct sk_buff *skb) 5917 { 5918 int ret; 5919 5920 rcu_read_lock(); 5921 ret = __netif_receive_skb_one_core(skb, false); 5922 rcu_read_unlock(); 5923 5924 return ret; 5925 } 5926 EXPORT_SYMBOL(netif_receive_skb_core); 5927 5928 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5929 struct packet_type *pt_prev, 5930 struct net_device *orig_dev) 5931 { 5932 struct sk_buff *skb, *next; 5933 5934 if (!pt_prev) 5935 return; 5936 if (list_empty(head)) 5937 return; 5938 if (pt_prev->list_func != NULL) 5939 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5940 ip_list_rcv, head, pt_prev, orig_dev); 5941 else 5942 list_for_each_entry_safe(skb, next, head, list) { 5943 skb_list_del_init(skb); 5944 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5945 } 5946 } 5947 5948 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5949 { 5950 /* Fast-path assumptions: 5951 * - There is no RX handler. 5952 * - Only one packet_type matches. 5953 * If either of these fails, we will end up doing some per-packet 5954 * processing in-line, then handling the 'last ptype' for the whole 5955 * sublist. This can't cause out-of-order delivery to any single ptype, 5956 * because the 'last ptype' must be constant across the sublist, and all 5957 * other ptypes are handled per-packet. 5958 */ 5959 /* Current (common) ptype of sublist */ 5960 struct packet_type *pt_curr = NULL; 5961 /* Current (common) orig_dev of sublist */ 5962 struct net_device *od_curr = NULL; 5963 struct sk_buff *skb, *next; 5964 LIST_HEAD(sublist); 5965 5966 list_for_each_entry_safe(skb, next, head, list) { 5967 struct net_device *orig_dev = skb->dev; 5968 struct packet_type *pt_prev = NULL; 5969 5970 skb_list_del_init(skb); 5971 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5972 if (!pt_prev) 5973 continue; 5974 if (pt_curr != pt_prev || od_curr != orig_dev) { 5975 /* dispatch old sublist */ 5976 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5977 /* start new sublist */ 5978 INIT_LIST_HEAD(&sublist); 5979 pt_curr = pt_prev; 5980 od_curr = orig_dev; 5981 } 5982 list_add_tail(&skb->list, &sublist); 5983 } 5984 5985 /* dispatch final sublist */ 5986 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5987 } 5988 5989 static int __netif_receive_skb(struct sk_buff *skb) 5990 { 5991 int ret; 5992 5993 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5994 unsigned int noreclaim_flag; 5995 5996 /* 5997 * PFMEMALLOC skbs are special, they should 5998 * - be delivered to SOCK_MEMALLOC sockets only 5999 * - stay away from userspace 6000 * - have bounded memory usage 6001 * 6002 * Use PF_MEMALLOC as this saves us from propagating the allocation 6003 * context down to all allocation sites. 6004 */ 6005 noreclaim_flag = memalloc_noreclaim_save(); 6006 ret = __netif_receive_skb_one_core(skb, true); 6007 memalloc_noreclaim_restore(noreclaim_flag); 6008 } else 6009 ret = __netif_receive_skb_one_core(skb, false); 6010 6011 return ret; 6012 } 6013 6014 static void __netif_receive_skb_list(struct list_head *head) 6015 { 6016 unsigned long noreclaim_flag = 0; 6017 struct sk_buff *skb, *next; 6018 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 6019 6020 list_for_each_entry_safe(skb, next, head, list) { 6021 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 6022 struct list_head sublist; 6023 6024 /* Handle the previous sublist */ 6025 list_cut_before(&sublist, head, &skb->list); 6026 if (!list_empty(&sublist)) 6027 __netif_receive_skb_list_core(&sublist, pfmemalloc); 6028 pfmemalloc = !pfmemalloc; 6029 /* See comments in __netif_receive_skb */ 6030 if (pfmemalloc) 6031 noreclaim_flag = memalloc_noreclaim_save(); 6032 else 6033 memalloc_noreclaim_restore(noreclaim_flag); 6034 } 6035 } 6036 /* Handle the remaining sublist */ 6037 if (!list_empty(head)) 6038 __netif_receive_skb_list_core(head, pfmemalloc); 6039 /* Restore pflags */ 6040 if (pfmemalloc) 6041 memalloc_noreclaim_restore(noreclaim_flag); 6042 } 6043 6044 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 6045 { 6046 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 6047 struct bpf_prog *new = xdp->prog; 6048 int ret = 0; 6049 6050 switch (xdp->command) { 6051 case XDP_SETUP_PROG: 6052 rcu_assign_pointer(dev->xdp_prog, new); 6053 if (old) 6054 bpf_prog_put(old); 6055 6056 if (old && !new) { 6057 static_branch_dec(&generic_xdp_needed_key); 6058 } else if (new && !old) { 6059 static_branch_inc(&generic_xdp_needed_key); 6060 dev_disable_lro(dev); 6061 dev_disable_gro_hw(dev); 6062 } 6063 break; 6064 6065 default: 6066 ret = -EINVAL; 6067 break; 6068 } 6069 6070 return ret; 6071 } 6072 6073 static int netif_receive_skb_internal(struct sk_buff *skb) 6074 { 6075 int ret; 6076 6077 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 6078 6079 if (skb_defer_rx_timestamp(skb)) 6080 return NET_RX_SUCCESS; 6081 6082 rcu_read_lock(); 6083 #ifdef CONFIG_RPS 6084 if (static_branch_unlikely(&rps_needed)) { 6085 struct rps_dev_flow voidflow, *rflow = &voidflow; 6086 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 6087 6088 if (cpu >= 0) { 6089 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 6090 rcu_read_unlock(); 6091 return ret; 6092 } 6093 } 6094 #endif 6095 ret = __netif_receive_skb(skb); 6096 rcu_read_unlock(); 6097 return ret; 6098 } 6099 6100 void netif_receive_skb_list_internal(struct list_head *head) 6101 { 6102 struct sk_buff *skb, *next; 6103 LIST_HEAD(sublist); 6104 6105 list_for_each_entry_safe(skb, next, head, list) { 6106 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), 6107 skb); 6108 skb_list_del_init(skb); 6109 if (!skb_defer_rx_timestamp(skb)) 6110 list_add_tail(&skb->list, &sublist); 6111 } 6112 list_splice_init(&sublist, head); 6113 6114 rcu_read_lock(); 6115 #ifdef CONFIG_RPS 6116 if (static_branch_unlikely(&rps_needed)) { 6117 list_for_each_entry_safe(skb, next, head, list) { 6118 struct rps_dev_flow voidflow, *rflow = &voidflow; 6119 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 6120 6121 if (cpu >= 0) { 6122 /* Will be handled, remove from list */ 6123 skb_list_del_init(skb); 6124 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 6125 } 6126 } 6127 } 6128 #endif 6129 __netif_receive_skb_list(head); 6130 rcu_read_unlock(); 6131 } 6132 6133 /** 6134 * netif_receive_skb - process receive buffer from network 6135 * @skb: buffer to process 6136 * 6137 * netif_receive_skb() is the main receive data processing function. 6138 * It always succeeds. The buffer may be dropped during processing 6139 * for congestion control or by the protocol layers. 6140 * 6141 * This function may only be called from softirq context and interrupts 6142 * should be enabled. 6143 * 6144 * Return values (usually ignored): 6145 * NET_RX_SUCCESS: no congestion 6146 * NET_RX_DROP: packet was dropped 6147 */ 6148 int netif_receive_skb(struct sk_buff *skb) 6149 { 6150 int ret; 6151 6152 trace_netif_receive_skb_entry(skb); 6153 6154 ret = netif_receive_skb_internal(skb); 6155 trace_netif_receive_skb_exit(ret); 6156 6157 return ret; 6158 } 6159 EXPORT_SYMBOL(netif_receive_skb); 6160 6161 /** 6162 * netif_receive_skb_list - process many receive buffers from network 6163 * @head: list of skbs to process. 6164 * 6165 * Since return value of netif_receive_skb() is normally ignored, and 6166 * wouldn't be meaningful for a list, this function returns void. 6167 * 6168 * This function may only be called from softirq context and interrupts 6169 * should be enabled. 6170 */ 6171 void netif_receive_skb_list(struct list_head *head) 6172 { 6173 struct sk_buff *skb; 6174 6175 if (list_empty(head)) 6176 return; 6177 if (trace_netif_receive_skb_list_entry_enabled()) { 6178 list_for_each_entry(skb, head, list) 6179 trace_netif_receive_skb_list_entry(skb); 6180 } 6181 netif_receive_skb_list_internal(head); 6182 trace_netif_receive_skb_list_exit(0); 6183 } 6184 EXPORT_SYMBOL(netif_receive_skb_list); 6185 6186 /* Network device is going away, flush any packets still pending */ 6187 static void flush_backlog(struct work_struct *work) 6188 { 6189 struct sk_buff *skb, *tmp; 6190 struct softnet_data *sd; 6191 6192 local_bh_disable(); 6193 sd = this_cpu_ptr(&softnet_data); 6194 6195 backlog_lock_irq_disable(sd); 6196 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 6197 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 6198 __skb_unlink(skb, &sd->input_pkt_queue); 6199 dev_kfree_skb_irq(skb); 6200 rps_input_queue_head_incr(sd); 6201 } 6202 } 6203 backlog_unlock_irq_enable(sd); 6204 6205 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6206 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 6207 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 6208 __skb_unlink(skb, &sd->process_queue); 6209 kfree_skb(skb); 6210 rps_input_queue_head_incr(sd); 6211 } 6212 } 6213 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6214 local_bh_enable(); 6215 } 6216 6217 static bool flush_required(int cpu) 6218 { 6219 #if IS_ENABLED(CONFIG_RPS) 6220 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 6221 bool do_flush; 6222 6223 backlog_lock_irq_disable(sd); 6224 6225 /* as insertion into process_queue happens with the rps lock held, 6226 * process_queue access may race only with dequeue 6227 */ 6228 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 6229 !skb_queue_empty_lockless(&sd->process_queue); 6230 backlog_unlock_irq_enable(sd); 6231 6232 return do_flush; 6233 #endif 6234 /* without RPS we can't safely check input_pkt_queue: during a 6235 * concurrent remote skb_queue_splice() we can detect as empty both 6236 * input_pkt_queue and process_queue even if the latter could end-up 6237 * containing a lot of packets. 6238 */ 6239 return true; 6240 } 6241 6242 struct flush_backlogs { 6243 cpumask_t flush_cpus; 6244 struct work_struct w[]; 6245 }; 6246 6247 static struct flush_backlogs *flush_backlogs_alloc(void) 6248 { 6249 return kmalloc(struct_size_t(struct flush_backlogs, w, nr_cpu_ids), 6250 GFP_KERNEL); 6251 } 6252 6253 static struct flush_backlogs *flush_backlogs_fallback; 6254 static DEFINE_MUTEX(flush_backlogs_mutex); 6255 6256 static void flush_all_backlogs(void) 6257 { 6258 struct flush_backlogs *ptr = flush_backlogs_alloc(); 6259 unsigned int cpu; 6260 6261 if (!ptr) { 6262 mutex_lock(&flush_backlogs_mutex); 6263 ptr = flush_backlogs_fallback; 6264 } 6265 cpumask_clear(&ptr->flush_cpus); 6266 6267 cpus_read_lock(); 6268 6269 for_each_online_cpu(cpu) { 6270 if (flush_required(cpu)) { 6271 INIT_WORK(&ptr->w[cpu], flush_backlog); 6272 queue_work_on(cpu, system_highpri_wq, &ptr->w[cpu]); 6273 __cpumask_set_cpu(cpu, &ptr->flush_cpus); 6274 } 6275 } 6276 6277 /* we can have in flight packet[s] on the cpus we are not flushing, 6278 * synchronize_net() in unregister_netdevice_many() will take care of 6279 * them. 6280 */ 6281 for_each_cpu(cpu, &ptr->flush_cpus) 6282 flush_work(&ptr->w[cpu]); 6283 6284 cpus_read_unlock(); 6285 6286 if (ptr != flush_backlogs_fallback) 6287 kfree(ptr); 6288 else 6289 mutex_unlock(&flush_backlogs_mutex); 6290 } 6291 6292 static void net_rps_send_ipi(struct softnet_data *remsd) 6293 { 6294 #ifdef CONFIG_RPS 6295 while (remsd) { 6296 struct softnet_data *next = remsd->rps_ipi_next; 6297 6298 if (cpu_online(remsd->cpu)) 6299 smp_call_function_single_async(remsd->cpu, &remsd->csd); 6300 remsd = next; 6301 } 6302 #endif 6303 } 6304 6305 /* 6306 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 6307 * Note: called with local irq disabled, but exits with local irq enabled. 6308 */ 6309 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 6310 { 6311 #ifdef CONFIG_RPS 6312 struct softnet_data *remsd = sd->rps_ipi_list; 6313 6314 if (!use_backlog_threads() && remsd) { 6315 sd->rps_ipi_list = NULL; 6316 6317 local_irq_enable(); 6318 6319 /* Send pending IPI's to kick RPS processing on remote cpus. */ 6320 net_rps_send_ipi(remsd); 6321 } else 6322 #endif 6323 local_irq_enable(); 6324 } 6325 6326 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 6327 { 6328 #ifdef CONFIG_RPS 6329 return !use_backlog_threads() && sd->rps_ipi_list; 6330 #else 6331 return false; 6332 #endif 6333 } 6334 6335 static int process_backlog(struct napi_struct *napi, int quota) 6336 { 6337 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 6338 bool again = true; 6339 int work = 0; 6340 6341 /* Check if we have pending ipi, its better to send them now, 6342 * not waiting net_rx_action() end. 6343 */ 6344 if (sd_has_rps_ipi_waiting(sd)) { 6345 local_irq_disable(); 6346 net_rps_action_and_irq_enable(sd); 6347 } 6348 6349 napi->weight = READ_ONCE(net_hotdata.dev_rx_weight); 6350 while (again) { 6351 struct sk_buff *skb; 6352 6353 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6354 while ((skb = __skb_dequeue(&sd->process_queue))) { 6355 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6356 rcu_read_lock(); 6357 __netif_receive_skb(skb); 6358 rcu_read_unlock(); 6359 if (++work >= quota) { 6360 rps_input_queue_head_add(sd, work); 6361 return work; 6362 } 6363 6364 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6365 } 6366 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6367 6368 backlog_lock_irq_disable(sd); 6369 if (skb_queue_empty(&sd->input_pkt_queue)) { 6370 /* 6371 * Inline a custom version of __napi_complete(). 6372 * only current cpu owns and manipulates this napi, 6373 * and NAPI_STATE_SCHED is the only possible flag set 6374 * on backlog. 6375 * We can use a plain write instead of clear_bit(), 6376 * and we dont need an smp_mb() memory barrier. 6377 */ 6378 napi->state &= NAPIF_STATE_THREADED; 6379 again = false; 6380 } else { 6381 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6382 skb_queue_splice_tail_init(&sd->input_pkt_queue, 6383 &sd->process_queue); 6384 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6385 } 6386 backlog_unlock_irq_enable(sd); 6387 } 6388 6389 if (work) 6390 rps_input_queue_head_add(sd, work); 6391 return work; 6392 } 6393 6394 /** 6395 * __napi_schedule - schedule for receive 6396 * @n: entry to schedule 6397 * 6398 * The entry's receive function will be scheduled to run. 6399 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 6400 */ 6401 void __napi_schedule(struct napi_struct *n) 6402 { 6403 unsigned long flags; 6404 6405 local_irq_save(flags); 6406 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6407 local_irq_restore(flags); 6408 } 6409 EXPORT_SYMBOL(__napi_schedule); 6410 6411 /** 6412 * napi_schedule_prep - check if napi can be scheduled 6413 * @n: napi context 6414 * 6415 * Test if NAPI routine is already running, and if not mark 6416 * it as running. This is used as a condition variable to 6417 * insure only one NAPI poll instance runs. We also make 6418 * sure there is no pending NAPI disable. 6419 */ 6420 bool napi_schedule_prep(struct napi_struct *n) 6421 { 6422 unsigned long new, val = READ_ONCE(n->state); 6423 6424 do { 6425 if (unlikely(val & NAPIF_STATE_DISABLE)) 6426 return false; 6427 new = val | NAPIF_STATE_SCHED; 6428 6429 /* Sets STATE_MISSED bit if STATE_SCHED was already set 6430 * This was suggested by Alexander Duyck, as compiler 6431 * emits better code than : 6432 * if (val & NAPIF_STATE_SCHED) 6433 * new |= NAPIF_STATE_MISSED; 6434 */ 6435 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6436 NAPIF_STATE_MISSED; 6437 } while (!try_cmpxchg(&n->state, &val, new)); 6438 6439 return !(val & NAPIF_STATE_SCHED); 6440 } 6441 EXPORT_SYMBOL(napi_schedule_prep); 6442 6443 /** 6444 * __napi_schedule_irqoff - schedule for receive 6445 * @n: entry to schedule 6446 * 6447 * Variant of __napi_schedule() assuming hard irqs are masked. 6448 * 6449 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6450 * because the interrupt disabled assumption might not be true 6451 * due to force-threaded interrupts and spinlock substitution. 6452 */ 6453 void __napi_schedule_irqoff(struct napi_struct *n) 6454 { 6455 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6456 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6457 else 6458 __napi_schedule(n); 6459 } 6460 EXPORT_SYMBOL(__napi_schedule_irqoff); 6461 6462 bool napi_complete_done(struct napi_struct *n, int work_done) 6463 { 6464 unsigned long flags, val, new, timeout = 0; 6465 bool ret = true; 6466 6467 /* 6468 * 1) Don't let napi dequeue from the cpu poll list 6469 * just in case its running on a different cpu. 6470 * 2) If we are busy polling, do nothing here, we have 6471 * the guarantee we will be called later. 6472 */ 6473 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6474 NAPIF_STATE_IN_BUSY_POLL))) 6475 return false; 6476 6477 if (work_done) { 6478 if (n->gro_bitmask) 6479 timeout = napi_get_gro_flush_timeout(n); 6480 n->defer_hard_irqs_count = napi_get_defer_hard_irqs(n); 6481 } 6482 if (n->defer_hard_irqs_count > 0) { 6483 n->defer_hard_irqs_count--; 6484 timeout = napi_get_gro_flush_timeout(n); 6485 if (timeout) 6486 ret = false; 6487 } 6488 if (n->gro_bitmask) { 6489 /* When the NAPI instance uses a timeout and keeps postponing 6490 * it, we need to bound somehow the time packets are kept in 6491 * the GRO layer 6492 */ 6493 napi_gro_flush(n, !!timeout); 6494 } 6495 6496 gro_normal_list(n); 6497 6498 if (unlikely(!list_empty(&n->poll_list))) { 6499 /* If n->poll_list is not empty, we need to mask irqs */ 6500 local_irq_save(flags); 6501 list_del_init(&n->poll_list); 6502 local_irq_restore(flags); 6503 } 6504 WRITE_ONCE(n->list_owner, -1); 6505 6506 val = READ_ONCE(n->state); 6507 do { 6508 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6509 6510 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6511 NAPIF_STATE_SCHED_THREADED | 6512 NAPIF_STATE_PREFER_BUSY_POLL); 6513 6514 /* If STATE_MISSED was set, leave STATE_SCHED set, 6515 * because we will call napi->poll() one more time. 6516 * This C code was suggested by Alexander Duyck to help gcc. 6517 */ 6518 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6519 NAPIF_STATE_SCHED; 6520 } while (!try_cmpxchg(&n->state, &val, new)); 6521 6522 if (unlikely(val & NAPIF_STATE_MISSED)) { 6523 __napi_schedule(n); 6524 return false; 6525 } 6526 6527 if (timeout) 6528 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6529 HRTIMER_MODE_REL_PINNED); 6530 return ret; 6531 } 6532 EXPORT_SYMBOL(napi_complete_done); 6533 6534 static void skb_defer_free_flush(struct softnet_data *sd) 6535 { 6536 struct sk_buff *skb, *next; 6537 6538 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6539 if (!READ_ONCE(sd->defer_list)) 6540 return; 6541 6542 spin_lock(&sd->defer_lock); 6543 skb = sd->defer_list; 6544 sd->defer_list = NULL; 6545 sd->defer_count = 0; 6546 spin_unlock(&sd->defer_lock); 6547 6548 while (skb != NULL) { 6549 next = skb->next; 6550 napi_consume_skb(skb, 1); 6551 skb = next; 6552 } 6553 } 6554 6555 #if defined(CONFIG_NET_RX_BUSY_POLL) 6556 6557 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6558 { 6559 if (!skip_schedule) { 6560 gro_normal_list(napi); 6561 __napi_schedule(napi); 6562 return; 6563 } 6564 6565 if (napi->gro_bitmask) { 6566 /* flush too old packets 6567 * If HZ < 1000, flush all packets. 6568 */ 6569 napi_gro_flush(napi, HZ >= 1000); 6570 } 6571 6572 gro_normal_list(napi); 6573 clear_bit(NAPI_STATE_SCHED, &napi->state); 6574 } 6575 6576 enum { 6577 NAPI_F_PREFER_BUSY_POLL = 1, 6578 NAPI_F_END_ON_RESCHED = 2, 6579 }; 6580 6581 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, 6582 unsigned flags, u16 budget) 6583 { 6584 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 6585 bool skip_schedule = false; 6586 unsigned long timeout; 6587 int rc; 6588 6589 /* Busy polling means there is a high chance device driver hard irq 6590 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6591 * set in napi_schedule_prep(). 6592 * Since we are about to call napi->poll() once more, we can safely 6593 * clear NAPI_STATE_MISSED. 6594 * 6595 * Note: x86 could use a single "lock and ..." instruction 6596 * to perform these two clear_bit() 6597 */ 6598 clear_bit(NAPI_STATE_MISSED, &napi->state); 6599 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6600 6601 local_bh_disable(); 6602 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 6603 6604 if (flags & NAPI_F_PREFER_BUSY_POLL) { 6605 napi->defer_hard_irqs_count = napi_get_defer_hard_irqs(napi); 6606 timeout = napi_get_gro_flush_timeout(napi); 6607 if (napi->defer_hard_irqs_count && timeout) { 6608 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6609 skip_schedule = true; 6610 } 6611 } 6612 6613 /* All we really want here is to re-enable device interrupts. 6614 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6615 */ 6616 rc = napi->poll(napi, budget); 6617 /* We can't gro_normal_list() here, because napi->poll() might have 6618 * rearmed the napi (napi_complete_done()) in which case it could 6619 * already be running on another CPU. 6620 */ 6621 trace_napi_poll(napi, rc, budget); 6622 netpoll_poll_unlock(have_poll_lock); 6623 if (rc == budget) 6624 __busy_poll_stop(napi, skip_schedule); 6625 bpf_net_ctx_clear(bpf_net_ctx); 6626 local_bh_enable(); 6627 } 6628 6629 static void __napi_busy_loop(unsigned int napi_id, 6630 bool (*loop_end)(void *, unsigned long), 6631 void *loop_end_arg, unsigned flags, u16 budget) 6632 { 6633 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6634 int (*napi_poll)(struct napi_struct *napi, int budget); 6635 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 6636 void *have_poll_lock = NULL; 6637 struct napi_struct *napi; 6638 6639 WARN_ON_ONCE(!rcu_read_lock_held()); 6640 6641 restart: 6642 napi_poll = NULL; 6643 6644 napi = napi_by_id(napi_id); 6645 if (!napi) 6646 return; 6647 6648 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6649 preempt_disable(); 6650 for (;;) { 6651 int work = 0; 6652 6653 local_bh_disable(); 6654 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 6655 if (!napi_poll) { 6656 unsigned long val = READ_ONCE(napi->state); 6657 6658 /* If multiple threads are competing for this napi, 6659 * we avoid dirtying napi->state as much as we can. 6660 */ 6661 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6662 NAPIF_STATE_IN_BUSY_POLL)) { 6663 if (flags & NAPI_F_PREFER_BUSY_POLL) 6664 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6665 goto count; 6666 } 6667 if (cmpxchg(&napi->state, val, 6668 val | NAPIF_STATE_IN_BUSY_POLL | 6669 NAPIF_STATE_SCHED) != val) { 6670 if (flags & NAPI_F_PREFER_BUSY_POLL) 6671 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6672 goto count; 6673 } 6674 have_poll_lock = netpoll_poll_lock(napi); 6675 napi_poll = napi->poll; 6676 } 6677 work = napi_poll(napi, budget); 6678 trace_napi_poll(napi, work, budget); 6679 gro_normal_list(napi); 6680 count: 6681 if (work > 0) 6682 __NET_ADD_STATS(dev_net(napi->dev), 6683 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6684 skb_defer_free_flush(this_cpu_ptr(&softnet_data)); 6685 bpf_net_ctx_clear(bpf_net_ctx); 6686 local_bh_enable(); 6687 6688 if (!loop_end || loop_end(loop_end_arg, start_time)) 6689 break; 6690 6691 if (unlikely(need_resched())) { 6692 if (flags & NAPI_F_END_ON_RESCHED) 6693 break; 6694 if (napi_poll) 6695 busy_poll_stop(napi, have_poll_lock, flags, budget); 6696 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6697 preempt_enable(); 6698 rcu_read_unlock(); 6699 cond_resched(); 6700 rcu_read_lock(); 6701 if (loop_end(loop_end_arg, start_time)) 6702 return; 6703 goto restart; 6704 } 6705 cpu_relax(); 6706 } 6707 if (napi_poll) 6708 busy_poll_stop(napi, have_poll_lock, flags, budget); 6709 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6710 preempt_enable(); 6711 } 6712 6713 void napi_busy_loop_rcu(unsigned int napi_id, 6714 bool (*loop_end)(void *, unsigned long), 6715 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6716 { 6717 unsigned flags = NAPI_F_END_ON_RESCHED; 6718 6719 if (prefer_busy_poll) 6720 flags |= NAPI_F_PREFER_BUSY_POLL; 6721 6722 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6723 } 6724 6725 void napi_busy_loop(unsigned int napi_id, 6726 bool (*loop_end)(void *, unsigned long), 6727 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6728 { 6729 unsigned flags = prefer_busy_poll ? NAPI_F_PREFER_BUSY_POLL : 0; 6730 6731 rcu_read_lock(); 6732 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6733 rcu_read_unlock(); 6734 } 6735 EXPORT_SYMBOL(napi_busy_loop); 6736 6737 void napi_suspend_irqs(unsigned int napi_id) 6738 { 6739 struct napi_struct *napi; 6740 6741 rcu_read_lock(); 6742 napi = napi_by_id(napi_id); 6743 if (napi) { 6744 unsigned long timeout = napi_get_irq_suspend_timeout(napi); 6745 6746 if (timeout) 6747 hrtimer_start(&napi->timer, ns_to_ktime(timeout), 6748 HRTIMER_MODE_REL_PINNED); 6749 } 6750 rcu_read_unlock(); 6751 } 6752 6753 void napi_resume_irqs(unsigned int napi_id) 6754 { 6755 struct napi_struct *napi; 6756 6757 rcu_read_lock(); 6758 napi = napi_by_id(napi_id); 6759 if (napi) { 6760 /* If irq_suspend_timeout is set to 0 between the call to 6761 * napi_suspend_irqs and now, the original value still 6762 * determines the safety timeout as intended and napi_watchdog 6763 * will resume irq processing. 6764 */ 6765 if (napi_get_irq_suspend_timeout(napi)) { 6766 local_bh_disable(); 6767 napi_schedule(napi); 6768 local_bh_enable(); 6769 } 6770 } 6771 rcu_read_unlock(); 6772 } 6773 6774 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6775 6776 static void __napi_hash_add_with_id(struct napi_struct *napi, 6777 unsigned int napi_id) 6778 { 6779 WRITE_ONCE(napi->napi_id, napi_id); 6780 hlist_add_head_rcu(&napi->napi_hash_node, 6781 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6782 } 6783 6784 static void napi_hash_add_with_id(struct napi_struct *napi, 6785 unsigned int napi_id) 6786 { 6787 unsigned long flags; 6788 6789 spin_lock_irqsave(&napi_hash_lock, flags); 6790 WARN_ON_ONCE(napi_by_id(napi_id)); 6791 __napi_hash_add_with_id(napi, napi_id); 6792 spin_unlock_irqrestore(&napi_hash_lock, flags); 6793 } 6794 6795 static void napi_hash_add(struct napi_struct *napi) 6796 { 6797 unsigned long flags; 6798 6799 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6800 return; 6801 6802 spin_lock_irqsave(&napi_hash_lock, flags); 6803 6804 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6805 do { 6806 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6807 napi_gen_id = MIN_NAPI_ID; 6808 } while (napi_by_id(napi_gen_id)); 6809 6810 __napi_hash_add_with_id(napi, napi_gen_id); 6811 6812 spin_unlock_irqrestore(&napi_hash_lock, flags); 6813 } 6814 6815 /* Warning : caller is responsible to make sure rcu grace period 6816 * is respected before freeing memory containing @napi 6817 */ 6818 static void napi_hash_del(struct napi_struct *napi) 6819 { 6820 unsigned long flags; 6821 6822 spin_lock_irqsave(&napi_hash_lock, flags); 6823 6824 hlist_del_init_rcu(&napi->napi_hash_node); 6825 6826 spin_unlock_irqrestore(&napi_hash_lock, flags); 6827 } 6828 6829 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6830 { 6831 struct napi_struct *napi; 6832 6833 napi = container_of(timer, struct napi_struct, timer); 6834 6835 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6836 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6837 */ 6838 if (!napi_disable_pending(napi) && 6839 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6840 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6841 __napi_schedule_irqoff(napi); 6842 } 6843 6844 return HRTIMER_NORESTART; 6845 } 6846 6847 static void init_gro_hash(struct napi_struct *napi) 6848 { 6849 int i; 6850 6851 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6852 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6853 napi->gro_hash[i].count = 0; 6854 } 6855 napi->gro_bitmask = 0; 6856 } 6857 6858 int dev_set_threaded(struct net_device *dev, bool threaded) 6859 { 6860 struct napi_struct *napi; 6861 int err = 0; 6862 6863 netdev_assert_locked_or_invisible(dev); 6864 6865 if (dev->threaded == threaded) 6866 return 0; 6867 6868 if (threaded) { 6869 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6870 if (!napi->thread) { 6871 err = napi_kthread_create(napi); 6872 if (err) { 6873 threaded = false; 6874 break; 6875 } 6876 } 6877 } 6878 } 6879 6880 WRITE_ONCE(dev->threaded, threaded); 6881 6882 /* Make sure kthread is created before THREADED bit 6883 * is set. 6884 */ 6885 smp_mb__before_atomic(); 6886 6887 /* Setting/unsetting threaded mode on a napi might not immediately 6888 * take effect, if the current napi instance is actively being 6889 * polled. In this case, the switch between threaded mode and 6890 * softirq mode will happen in the next round of napi_schedule(). 6891 * This should not cause hiccups/stalls to the live traffic. 6892 */ 6893 list_for_each_entry(napi, &dev->napi_list, dev_list) 6894 assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); 6895 6896 return err; 6897 } 6898 EXPORT_SYMBOL(dev_set_threaded); 6899 6900 /** 6901 * netif_queue_set_napi - Associate queue with the napi 6902 * @dev: device to which NAPI and queue belong 6903 * @queue_index: Index of queue 6904 * @type: queue type as RX or TX 6905 * @napi: NAPI context, pass NULL to clear previously set NAPI 6906 * 6907 * Set queue with its corresponding napi context. This should be done after 6908 * registering the NAPI handler for the queue-vector and the queues have been 6909 * mapped to the corresponding interrupt vector. 6910 */ 6911 void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index, 6912 enum netdev_queue_type type, struct napi_struct *napi) 6913 { 6914 struct netdev_rx_queue *rxq; 6915 struct netdev_queue *txq; 6916 6917 if (WARN_ON_ONCE(napi && !napi->dev)) 6918 return; 6919 if (dev->reg_state >= NETREG_REGISTERED) 6920 ASSERT_RTNL(); 6921 6922 switch (type) { 6923 case NETDEV_QUEUE_TYPE_RX: 6924 rxq = __netif_get_rx_queue(dev, queue_index); 6925 rxq->napi = napi; 6926 return; 6927 case NETDEV_QUEUE_TYPE_TX: 6928 txq = netdev_get_tx_queue(dev, queue_index); 6929 txq->napi = napi; 6930 return; 6931 default: 6932 return; 6933 } 6934 } 6935 EXPORT_SYMBOL(netif_queue_set_napi); 6936 6937 static void napi_restore_config(struct napi_struct *n) 6938 { 6939 n->defer_hard_irqs = n->config->defer_hard_irqs; 6940 n->gro_flush_timeout = n->config->gro_flush_timeout; 6941 n->irq_suspend_timeout = n->config->irq_suspend_timeout; 6942 /* a NAPI ID might be stored in the config, if so use it. if not, use 6943 * napi_hash_add to generate one for us. 6944 */ 6945 if (n->config->napi_id) { 6946 napi_hash_add_with_id(n, n->config->napi_id); 6947 } else { 6948 napi_hash_add(n); 6949 n->config->napi_id = n->napi_id; 6950 } 6951 } 6952 6953 static void napi_save_config(struct napi_struct *n) 6954 { 6955 n->config->defer_hard_irqs = n->defer_hard_irqs; 6956 n->config->gro_flush_timeout = n->gro_flush_timeout; 6957 n->config->irq_suspend_timeout = n->irq_suspend_timeout; 6958 napi_hash_del(n); 6959 } 6960 6961 /* Netlink wants the NAPI list to be sorted by ID, if adding a NAPI which will 6962 * inherit an existing ID try to insert it at the right position. 6963 */ 6964 static void 6965 netif_napi_dev_list_add(struct net_device *dev, struct napi_struct *napi) 6966 { 6967 unsigned int new_id, pos_id; 6968 struct list_head *higher; 6969 struct napi_struct *pos; 6970 6971 new_id = UINT_MAX; 6972 if (napi->config && napi->config->napi_id) 6973 new_id = napi->config->napi_id; 6974 6975 higher = &dev->napi_list; 6976 list_for_each_entry(pos, &dev->napi_list, dev_list) { 6977 if (pos->napi_id >= MIN_NAPI_ID) 6978 pos_id = pos->napi_id; 6979 else if (pos->config) 6980 pos_id = pos->config->napi_id; 6981 else 6982 pos_id = UINT_MAX; 6983 6984 if (pos_id <= new_id) 6985 break; 6986 higher = &pos->dev_list; 6987 } 6988 list_add_rcu(&napi->dev_list, higher); /* adds after higher */ 6989 } 6990 6991 /* Double check that napi_get_frags() allocates skbs with 6992 * skb->head being backed by slab, not a page fragment. 6993 * This is to make sure bug fixed in 3226b158e67c 6994 * ("net: avoid 32 x truesize under-estimation for tiny skbs") 6995 * does not accidentally come back. 6996 */ 6997 static void napi_get_frags_check(struct napi_struct *napi) 6998 { 6999 struct sk_buff *skb; 7000 7001 local_bh_disable(); 7002 skb = napi_get_frags(napi); 7003 WARN_ON_ONCE(skb && skb->head_frag); 7004 napi_free_frags(napi); 7005 local_bh_enable(); 7006 } 7007 7008 void netif_napi_add_weight_locked(struct net_device *dev, 7009 struct napi_struct *napi, 7010 int (*poll)(struct napi_struct *, int), 7011 int weight) 7012 { 7013 netdev_assert_locked(dev); 7014 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 7015 return; 7016 7017 INIT_LIST_HEAD(&napi->poll_list); 7018 INIT_HLIST_NODE(&napi->napi_hash_node); 7019 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 7020 napi->timer.function = napi_watchdog; 7021 init_gro_hash(napi); 7022 napi->skb = NULL; 7023 INIT_LIST_HEAD(&napi->rx_list); 7024 napi->rx_count = 0; 7025 napi->poll = poll; 7026 if (weight > NAPI_POLL_WEIGHT) 7027 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 7028 weight); 7029 napi->weight = weight; 7030 napi->dev = dev; 7031 #ifdef CONFIG_NETPOLL 7032 napi->poll_owner = -1; 7033 #endif 7034 napi->list_owner = -1; 7035 set_bit(NAPI_STATE_SCHED, &napi->state); 7036 set_bit(NAPI_STATE_NPSVC, &napi->state); 7037 netif_napi_dev_list_add(dev, napi); 7038 7039 /* default settings from sysfs are applied to all NAPIs. any per-NAPI 7040 * configuration will be loaded in napi_enable 7041 */ 7042 napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); 7043 napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout)); 7044 7045 napi_get_frags_check(napi); 7046 /* Create kthread for this napi if dev->threaded is set. 7047 * Clear dev->threaded if kthread creation failed so that 7048 * threaded mode will not be enabled in napi_enable(). 7049 */ 7050 if (dev->threaded && napi_kthread_create(napi)) 7051 dev->threaded = false; 7052 netif_napi_set_irq_locked(napi, -1); 7053 } 7054 EXPORT_SYMBOL(netif_napi_add_weight_locked); 7055 7056 void napi_disable_locked(struct napi_struct *n) 7057 { 7058 unsigned long val, new; 7059 7060 might_sleep(); 7061 netdev_assert_locked(n->dev); 7062 7063 set_bit(NAPI_STATE_DISABLE, &n->state); 7064 7065 val = READ_ONCE(n->state); 7066 do { 7067 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 7068 usleep_range(20, 200); 7069 val = READ_ONCE(n->state); 7070 } 7071 7072 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 7073 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 7074 } while (!try_cmpxchg(&n->state, &val, new)); 7075 7076 hrtimer_cancel(&n->timer); 7077 7078 if (n->config) 7079 napi_save_config(n); 7080 else 7081 napi_hash_del(n); 7082 7083 clear_bit(NAPI_STATE_DISABLE, &n->state); 7084 } 7085 EXPORT_SYMBOL(napi_disable_locked); 7086 7087 /** 7088 * napi_disable() - prevent NAPI from scheduling 7089 * @n: NAPI context 7090 * 7091 * Stop NAPI from being scheduled on this context. 7092 * Waits till any outstanding processing completes. 7093 * Takes netdev_lock() for associated net_device. 7094 */ 7095 void napi_disable(struct napi_struct *n) 7096 { 7097 netdev_lock(n->dev); 7098 napi_disable_locked(n); 7099 netdev_unlock(n->dev); 7100 } 7101 EXPORT_SYMBOL(napi_disable); 7102 7103 void napi_enable_locked(struct napi_struct *n) 7104 { 7105 unsigned long new, val = READ_ONCE(n->state); 7106 7107 if (n->config) 7108 napi_restore_config(n); 7109 else 7110 napi_hash_add(n); 7111 7112 do { 7113 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 7114 7115 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 7116 if (n->dev->threaded && n->thread) 7117 new |= NAPIF_STATE_THREADED; 7118 } while (!try_cmpxchg(&n->state, &val, new)); 7119 } 7120 EXPORT_SYMBOL(napi_enable_locked); 7121 7122 /** 7123 * napi_enable() - enable NAPI scheduling 7124 * @n: NAPI context 7125 * 7126 * Enable scheduling of a NAPI instance. 7127 * Must be paired with napi_disable(). 7128 * Takes netdev_lock() for associated net_device. 7129 */ 7130 void napi_enable(struct napi_struct *n) 7131 { 7132 netdev_lock(n->dev); 7133 napi_enable_locked(n); 7134 netdev_unlock(n->dev); 7135 } 7136 EXPORT_SYMBOL(napi_enable); 7137 7138 static void flush_gro_hash(struct napi_struct *napi) 7139 { 7140 int i; 7141 7142 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 7143 struct sk_buff *skb, *n; 7144 7145 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 7146 kfree_skb(skb); 7147 napi->gro_hash[i].count = 0; 7148 } 7149 } 7150 7151 /* Must be called in process context */ 7152 void __netif_napi_del_locked(struct napi_struct *napi) 7153 { 7154 netdev_assert_locked(napi->dev); 7155 7156 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 7157 return; 7158 7159 if (napi->config) { 7160 napi->index = -1; 7161 napi->config = NULL; 7162 } 7163 7164 list_del_rcu(&napi->dev_list); 7165 napi_free_frags(napi); 7166 7167 flush_gro_hash(napi); 7168 napi->gro_bitmask = 0; 7169 7170 if (napi->thread) { 7171 kthread_stop(napi->thread); 7172 napi->thread = NULL; 7173 } 7174 } 7175 EXPORT_SYMBOL(__netif_napi_del_locked); 7176 7177 static int __napi_poll(struct napi_struct *n, bool *repoll) 7178 { 7179 int work, weight; 7180 7181 weight = n->weight; 7182 7183 /* This NAPI_STATE_SCHED test is for avoiding a race 7184 * with netpoll's poll_napi(). Only the entity which 7185 * obtains the lock and sees NAPI_STATE_SCHED set will 7186 * actually make the ->poll() call. Therefore we avoid 7187 * accidentally calling ->poll() when NAPI is not scheduled. 7188 */ 7189 work = 0; 7190 if (napi_is_scheduled(n)) { 7191 work = n->poll(n, weight); 7192 trace_napi_poll(n, work, weight); 7193 7194 xdp_do_check_flushed(n); 7195 } 7196 7197 if (unlikely(work > weight)) 7198 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 7199 n->poll, work, weight); 7200 7201 if (likely(work < weight)) 7202 return work; 7203 7204 /* Drivers must not modify the NAPI state if they 7205 * consume the entire weight. In such cases this code 7206 * still "owns" the NAPI instance and therefore can 7207 * move the instance around on the list at-will. 7208 */ 7209 if (unlikely(napi_disable_pending(n))) { 7210 napi_complete(n); 7211 return work; 7212 } 7213 7214 /* The NAPI context has more processing work, but busy-polling 7215 * is preferred. Exit early. 7216 */ 7217 if (napi_prefer_busy_poll(n)) { 7218 if (napi_complete_done(n, work)) { 7219 /* If timeout is not set, we need to make sure 7220 * that the NAPI is re-scheduled. 7221 */ 7222 napi_schedule(n); 7223 } 7224 return work; 7225 } 7226 7227 if (n->gro_bitmask) { 7228 /* flush too old packets 7229 * If HZ < 1000, flush all packets. 7230 */ 7231 napi_gro_flush(n, HZ >= 1000); 7232 } 7233 7234 gro_normal_list(n); 7235 7236 /* Some drivers may have called napi_schedule 7237 * prior to exhausting their budget. 7238 */ 7239 if (unlikely(!list_empty(&n->poll_list))) { 7240 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 7241 n->dev ? n->dev->name : "backlog"); 7242 return work; 7243 } 7244 7245 *repoll = true; 7246 7247 return work; 7248 } 7249 7250 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 7251 { 7252 bool do_repoll = false; 7253 void *have; 7254 int work; 7255 7256 list_del_init(&n->poll_list); 7257 7258 have = netpoll_poll_lock(n); 7259 7260 work = __napi_poll(n, &do_repoll); 7261 7262 if (do_repoll) 7263 list_add_tail(&n->poll_list, repoll); 7264 7265 netpoll_poll_unlock(have); 7266 7267 return work; 7268 } 7269 7270 static int napi_thread_wait(struct napi_struct *napi) 7271 { 7272 set_current_state(TASK_INTERRUPTIBLE); 7273 7274 while (!kthread_should_stop()) { 7275 /* Testing SCHED_THREADED bit here to make sure the current 7276 * kthread owns this napi and could poll on this napi. 7277 * Testing SCHED bit is not enough because SCHED bit might be 7278 * set by some other busy poll thread or by napi_disable(). 7279 */ 7280 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state)) { 7281 WARN_ON(!list_empty(&napi->poll_list)); 7282 __set_current_state(TASK_RUNNING); 7283 return 0; 7284 } 7285 7286 schedule(); 7287 set_current_state(TASK_INTERRUPTIBLE); 7288 } 7289 __set_current_state(TASK_RUNNING); 7290 7291 return -1; 7292 } 7293 7294 static void napi_threaded_poll_loop(struct napi_struct *napi) 7295 { 7296 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 7297 struct softnet_data *sd; 7298 unsigned long last_qs = jiffies; 7299 7300 for (;;) { 7301 bool repoll = false; 7302 void *have; 7303 7304 local_bh_disable(); 7305 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 7306 7307 sd = this_cpu_ptr(&softnet_data); 7308 sd->in_napi_threaded_poll = true; 7309 7310 have = netpoll_poll_lock(napi); 7311 __napi_poll(napi, &repoll); 7312 netpoll_poll_unlock(have); 7313 7314 sd->in_napi_threaded_poll = false; 7315 barrier(); 7316 7317 if (sd_has_rps_ipi_waiting(sd)) { 7318 local_irq_disable(); 7319 net_rps_action_and_irq_enable(sd); 7320 } 7321 skb_defer_free_flush(sd); 7322 bpf_net_ctx_clear(bpf_net_ctx); 7323 local_bh_enable(); 7324 7325 if (!repoll) 7326 break; 7327 7328 rcu_softirq_qs_periodic(last_qs); 7329 cond_resched(); 7330 } 7331 } 7332 7333 static int napi_threaded_poll(void *data) 7334 { 7335 struct napi_struct *napi = data; 7336 7337 while (!napi_thread_wait(napi)) 7338 napi_threaded_poll_loop(napi); 7339 7340 return 0; 7341 } 7342 7343 static __latent_entropy void net_rx_action(void) 7344 { 7345 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 7346 unsigned long time_limit = jiffies + 7347 usecs_to_jiffies(READ_ONCE(net_hotdata.netdev_budget_usecs)); 7348 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 7349 int budget = READ_ONCE(net_hotdata.netdev_budget); 7350 LIST_HEAD(list); 7351 LIST_HEAD(repoll); 7352 7353 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 7354 start: 7355 sd->in_net_rx_action = true; 7356 local_irq_disable(); 7357 list_splice_init(&sd->poll_list, &list); 7358 local_irq_enable(); 7359 7360 for (;;) { 7361 struct napi_struct *n; 7362 7363 skb_defer_free_flush(sd); 7364 7365 if (list_empty(&list)) { 7366 if (list_empty(&repoll)) { 7367 sd->in_net_rx_action = false; 7368 barrier(); 7369 /* We need to check if ____napi_schedule() 7370 * had refilled poll_list while 7371 * sd->in_net_rx_action was true. 7372 */ 7373 if (!list_empty(&sd->poll_list)) 7374 goto start; 7375 if (!sd_has_rps_ipi_waiting(sd)) 7376 goto end; 7377 } 7378 break; 7379 } 7380 7381 n = list_first_entry(&list, struct napi_struct, poll_list); 7382 budget -= napi_poll(n, &repoll); 7383 7384 /* If softirq window is exhausted then punt. 7385 * Allow this to run for 2 jiffies since which will allow 7386 * an average latency of 1.5/HZ. 7387 */ 7388 if (unlikely(budget <= 0 || 7389 time_after_eq(jiffies, time_limit))) { 7390 sd->time_squeeze++; 7391 break; 7392 } 7393 } 7394 7395 local_irq_disable(); 7396 7397 list_splice_tail_init(&sd->poll_list, &list); 7398 list_splice_tail(&repoll, &list); 7399 list_splice(&list, &sd->poll_list); 7400 if (!list_empty(&sd->poll_list)) 7401 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 7402 else 7403 sd->in_net_rx_action = false; 7404 7405 net_rps_action_and_irq_enable(sd); 7406 end: 7407 bpf_net_ctx_clear(bpf_net_ctx); 7408 } 7409 7410 struct netdev_adjacent { 7411 struct net_device *dev; 7412 netdevice_tracker dev_tracker; 7413 7414 /* upper master flag, there can only be one master device per list */ 7415 bool master; 7416 7417 /* lookup ignore flag */ 7418 bool ignore; 7419 7420 /* counter for the number of times this device was added to us */ 7421 u16 ref_nr; 7422 7423 /* private field for the users */ 7424 void *private; 7425 7426 struct list_head list; 7427 struct rcu_head rcu; 7428 }; 7429 7430 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 7431 struct list_head *adj_list) 7432 { 7433 struct netdev_adjacent *adj; 7434 7435 list_for_each_entry(adj, adj_list, list) { 7436 if (adj->dev == adj_dev) 7437 return adj; 7438 } 7439 return NULL; 7440 } 7441 7442 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 7443 struct netdev_nested_priv *priv) 7444 { 7445 struct net_device *dev = (struct net_device *)priv->data; 7446 7447 return upper_dev == dev; 7448 } 7449 7450 /** 7451 * netdev_has_upper_dev - Check if device is linked to an upper device 7452 * @dev: device 7453 * @upper_dev: upper device to check 7454 * 7455 * Find out if a device is linked to specified upper device and return true 7456 * in case it is. Note that this checks only immediate upper device, 7457 * not through a complete stack of devices. The caller must hold the RTNL lock. 7458 */ 7459 bool netdev_has_upper_dev(struct net_device *dev, 7460 struct net_device *upper_dev) 7461 { 7462 struct netdev_nested_priv priv = { 7463 .data = (void *)upper_dev, 7464 }; 7465 7466 ASSERT_RTNL(); 7467 7468 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 7469 &priv); 7470 } 7471 EXPORT_SYMBOL(netdev_has_upper_dev); 7472 7473 /** 7474 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 7475 * @dev: device 7476 * @upper_dev: upper device to check 7477 * 7478 * Find out if a device is linked to specified upper device and return true 7479 * in case it is. Note that this checks the entire upper device chain. 7480 * The caller must hold rcu lock. 7481 */ 7482 7483 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 7484 struct net_device *upper_dev) 7485 { 7486 struct netdev_nested_priv priv = { 7487 .data = (void *)upper_dev, 7488 }; 7489 7490 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 7491 &priv); 7492 } 7493 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 7494 7495 /** 7496 * netdev_has_any_upper_dev - Check if device is linked to some device 7497 * @dev: device 7498 * 7499 * Find out if a device is linked to an upper device and return true in case 7500 * it is. The caller must hold the RTNL lock. 7501 */ 7502 bool netdev_has_any_upper_dev(struct net_device *dev) 7503 { 7504 ASSERT_RTNL(); 7505 7506 return !list_empty(&dev->adj_list.upper); 7507 } 7508 EXPORT_SYMBOL(netdev_has_any_upper_dev); 7509 7510 /** 7511 * netdev_master_upper_dev_get - Get master upper device 7512 * @dev: device 7513 * 7514 * Find a master upper device and return pointer to it or NULL in case 7515 * it's not there. The caller must hold the RTNL lock. 7516 */ 7517 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 7518 { 7519 struct netdev_adjacent *upper; 7520 7521 ASSERT_RTNL(); 7522 7523 if (list_empty(&dev->adj_list.upper)) 7524 return NULL; 7525 7526 upper = list_first_entry(&dev->adj_list.upper, 7527 struct netdev_adjacent, list); 7528 if (likely(upper->master)) 7529 return upper->dev; 7530 return NULL; 7531 } 7532 EXPORT_SYMBOL(netdev_master_upper_dev_get); 7533 7534 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 7535 { 7536 struct netdev_adjacent *upper; 7537 7538 ASSERT_RTNL(); 7539 7540 if (list_empty(&dev->adj_list.upper)) 7541 return NULL; 7542 7543 upper = list_first_entry(&dev->adj_list.upper, 7544 struct netdev_adjacent, list); 7545 if (likely(upper->master) && !upper->ignore) 7546 return upper->dev; 7547 return NULL; 7548 } 7549 7550 /** 7551 * netdev_has_any_lower_dev - Check if device is linked to some device 7552 * @dev: device 7553 * 7554 * Find out if a device is linked to a lower device and return true in case 7555 * it is. The caller must hold the RTNL lock. 7556 */ 7557 static bool netdev_has_any_lower_dev(struct net_device *dev) 7558 { 7559 ASSERT_RTNL(); 7560 7561 return !list_empty(&dev->adj_list.lower); 7562 } 7563 7564 void *netdev_adjacent_get_private(struct list_head *adj_list) 7565 { 7566 struct netdev_adjacent *adj; 7567 7568 adj = list_entry(adj_list, struct netdev_adjacent, list); 7569 7570 return adj->private; 7571 } 7572 EXPORT_SYMBOL(netdev_adjacent_get_private); 7573 7574 /** 7575 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 7576 * @dev: device 7577 * @iter: list_head ** of the current position 7578 * 7579 * Gets the next device from the dev's upper list, starting from iter 7580 * position. The caller must hold RCU read lock. 7581 */ 7582 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 7583 struct list_head **iter) 7584 { 7585 struct netdev_adjacent *upper; 7586 7587 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 7588 7589 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7590 7591 if (&upper->list == &dev->adj_list.upper) 7592 return NULL; 7593 7594 *iter = &upper->list; 7595 7596 return upper->dev; 7597 } 7598 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 7599 7600 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 7601 struct list_head **iter, 7602 bool *ignore) 7603 { 7604 struct netdev_adjacent *upper; 7605 7606 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 7607 7608 if (&upper->list == &dev->adj_list.upper) 7609 return NULL; 7610 7611 *iter = &upper->list; 7612 *ignore = upper->ignore; 7613 7614 return upper->dev; 7615 } 7616 7617 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 7618 struct list_head **iter) 7619 { 7620 struct netdev_adjacent *upper; 7621 7622 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 7623 7624 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7625 7626 if (&upper->list == &dev->adj_list.upper) 7627 return NULL; 7628 7629 *iter = &upper->list; 7630 7631 return upper->dev; 7632 } 7633 7634 static int __netdev_walk_all_upper_dev(struct net_device *dev, 7635 int (*fn)(struct net_device *dev, 7636 struct netdev_nested_priv *priv), 7637 struct netdev_nested_priv *priv) 7638 { 7639 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7640 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7641 int ret, cur = 0; 7642 bool ignore; 7643 7644 now = dev; 7645 iter = &dev->adj_list.upper; 7646 7647 while (1) { 7648 if (now != dev) { 7649 ret = fn(now, priv); 7650 if (ret) 7651 return ret; 7652 } 7653 7654 next = NULL; 7655 while (1) { 7656 udev = __netdev_next_upper_dev(now, &iter, &ignore); 7657 if (!udev) 7658 break; 7659 if (ignore) 7660 continue; 7661 7662 next = udev; 7663 niter = &udev->adj_list.upper; 7664 dev_stack[cur] = now; 7665 iter_stack[cur++] = iter; 7666 break; 7667 } 7668 7669 if (!next) { 7670 if (!cur) 7671 return 0; 7672 next = dev_stack[--cur]; 7673 niter = iter_stack[cur]; 7674 } 7675 7676 now = next; 7677 iter = niter; 7678 } 7679 7680 return 0; 7681 } 7682 7683 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 7684 int (*fn)(struct net_device *dev, 7685 struct netdev_nested_priv *priv), 7686 struct netdev_nested_priv *priv) 7687 { 7688 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7689 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7690 int ret, cur = 0; 7691 7692 now = dev; 7693 iter = &dev->adj_list.upper; 7694 7695 while (1) { 7696 if (now != dev) { 7697 ret = fn(now, priv); 7698 if (ret) 7699 return ret; 7700 } 7701 7702 next = NULL; 7703 while (1) { 7704 udev = netdev_next_upper_dev_rcu(now, &iter); 7705 if (!udev) 7706 break; 7707 7708 next = udev; 7709 niter = &udev->adj_list.upper; 7710 dev_stack[cur] = now; 7711 iter_stack[cur++] = iter; 7712 break; 7713 } 7714 7715 if (!next) { 7716 if (!cur) 7717 return 0; 7718 next = dev_stack[--cur]; 7719 niter = iter_stack[cur]; 7720 } 7721 7722 now = next; 7723 iter = niter; 7724 } 7725 7726 return 0; 7727 } 7728 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 7729 7730 static bool __netdev_has_upper_dev(struct net_device *dev, 7731 struct net_device *upper_dev) 7732 { 7733 struct netdev_nested_priv priv = { 7734 .flags = 0, 7735 .data = (void *)upper_dev, 7736 }; 7737 7738 ASSERT_RTNL(); 7739 7740 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 7741 &priv); 7742 } 7743 7744 /** 7745 * netdev_lower_get_next_private - Get the next ->private from the 7746 * lower neighbour list 7747 * @dev: device 7748 * @iter: list_head ** of the current position 7749 * 7750 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7751 * list, starting from iter position. The caller must hold either hold the 7752 * RTNL lock or its own locking that guarantees that the neighbour lower 7753 * list will remain unchanged. 7754 */ 7755 void *netdev_lower_get_next_private(struct net_device *dev, 7756 struct list_head **iter) 7757 { 7758 struct netdev_adjacent *lower; 7759 7760 lower = list_entry(*iter, struct netdev_adjacent, list); 7761 7762 if (&lower->list == &dev->adj_list.lower) 7763 return NULL; 7764 7765 *iter = lower->list.next; 7766 7767 return lower->private; 7768 } 7769 EXPORT_SYMBOL(netdev_lower_get_next_private); 7770 7771 /** 7772 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7773 * lower neighbour list, RCU 7774 * variant 7775 * @dev: device 7776 * @iter: list_head ** of the current position 7777 * 7778 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7779 * list, starting from iter position. The caller must hold RCU read lock. 7780 */ 7781 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7782 struct list_head **iter) 7783 { 7784 struct netdev_adjacent *lower; 7785 7786 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7787 7788 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7789 7790 if (&lower->list == &dev->adj_list.lower) 7791 return NULL; 7792 7793 *iter = &lower->list; 7794 7795 return lower->private; 7796 } 7797 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7798 7799 /** 7800 * netdev_lower_get_next - Get the next device from the lower neighbour 7801 * list 7802 * @dev: device 7803 * @iter: list_head ** of the current position 7804 * 7805 * Gets the next netdev_adjacent from the dev's lower neighbour 7806 * list, starting from iter position. The caller must hold RTNL lock or 7807 * its own locking that guarantees that the neighbour lower 7808 * list will remain unchanged. 7809 */ 7810 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7811 { 7812 struct netdev_adjacent *lower; 7813 7814 lower = list_entry(*iter, struct netdev_adjacent, list); 7815 7816 if (&lower->list == &dev->adj_list.lower) 7817 return NULL; 7818 7819 *iter = lower->list.next; 7820 7821 return lower->dev; 7822 } 7823 EXPORT_SYMBOL(netdev_lower_get_next); 7824 7825 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7826 struct list_head **iter) 7827 { 7828 struct netdev_adjacent *lower; 7829 7830 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7831 7832 if (&lower->list == &dev->adj_list.lower) 7833 return NULL; 7834 7835 *iter = &lower->list; 7836 7837 return lower->dev; 7838 } 7839 7840 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7841 struct list_head **iter, 7842 bool *ignore) 7843 { 7844 struct netdev_adjacent *lower; 7845 7846 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7847 7848 if (&lower->list == &dev->adj_list.lower) 7849 return NULL; 7850 7851 *iter = &lower->list; 7852 *ignore = lower->ignore; 7853 7854 return lower->dev; 7855 } 7856 7857 int netdev_walk_all_lower_dev(struct net_device *dev, 7858 int (*fn)(struct net_device *dev, 7859 struct netdev_nested_priv *priv), 7860 struct netdev_nested_priv *priv) 7861 { 7862 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7863 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7864 int ret, cur = 0; 7865 7866 now = dev; 7867 iter = &dev->adj_list.lower; 7868 7869 while (1) { 7870 if (now != dev) { 7871 ret = fn(now, priv); 7872 if (ret) 7873 return ret; 7874 } 7875 7876 next = NULL; 7877 while (1) { 7878 ldev = netdev_next_lower_dev(now, &iter); 7879 if (!ldev) 7880 break; 7881 7882 next = ldev; 7883 niter = &ldev->adj_list.lower; 7884 dev_stack[cur] = now; 7885 iter_stack[cur++] = iter; 7886 break; 7887 } 7888 7889 if (!next) { 7890 if (!cur) 7891 return 0; 7892 next = dev_stack[--cur]; 7893 niter = iter_stack[cur]; 7894 } 7895 7896 now = next; 7897 iter = niter; 7898 } 7899 7900 return 0; 7901 } 7902 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7903 7904 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7905 int (*fn)(struct net_device *dev, 7906 struct netdev_nested_priv *priv), 7907 struct netdev_nested_priv *priv) 7908 { 7909 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7910 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7911 int ret, cur = 0; 7912 bool ignore; 7913 7914 now = dev; 7915 iter = &dev->adj_list.lower; 7916 7917 while (1) { 7918 if (now != dev) { 7919 ret = fn(now, priv); 7920 if (ret) 7921 return ret; 7922 } 7923 7924 next = NULL; 7925 while (1) { 7926 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7927 if (!ldev) 7928 break; 7929 if (ignore) 7930 continue; 7931 7932 next = ldev; 7933 niter = &ldev->adj_list.lower; 7934 dev_stack[cur] = now; 7935 iter_stack[cur++] = iter; 7936 break; 7937 } 7938 7939 if (!next) { 7940 if (!cur) 7941 return 0; 7942 next = dev_stack[--cur]; 7943 niter = iter_stack[cur]; 7944 } 7945 7946 now = next; 7947 iter = niter; 7948 } 7949 7950 return 0; 7951 } 7952 7953 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7954 struct list_head **iter) 7955 { 7956 struct netdev_adjacent *lower; 7957 7958 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7959 if (&lower->list == &dev->adj_list.lower) 7960 return NULL; 7961 7962 *iter = &lower->list; 7963 7964 return lower->dev; 7965 } 7966 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7967 7968 static u8 __netdev_upper_depth(struct net_device *dev) 7969 { 7970 struct net_device *udev; 7971 struct list_head *iter; 7972 u8 max_depth = 0; 7973 bool ignore; 7974 7975 for (iter = &dev->adj_list.upper, 7976 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7977 udev; 7978 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7979 if (ignore) 7980 continue; 7981 if (max_depth < udev->upper_level) 7982 max_depth = udev->upper_level; 7983 } 7984 7985 return max_depth; 7986 } 7987 7988 static u8 __netdev_lower_depth(struct net_device *dev) 7989 { 7990 struct net_device *ldev; 7991 struct list_head *iter; 7992 u8 max_depth = 0; 7993 bool ignore; 7994 7995 for (iter = &dev->adj_list.lower, 7996 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7997 ldev; 7998 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7999 if (ignore) 8000 continue; 8001 if (max_depth < ldev->lower_level) 8002 max_depth = ldev->lower_level; 8003 } 8004 8005 return max_depth; 8006 } 8007 8008 static int __netdev_update_upper_level(struct net_device *dev, 8009 struct netdev_nested_priv *__unused) 8010 { 8011 dev->upper_level = __netdev_upper_depth(dev) + 1; 8012 return 0; 8013 } 8014 8015 #ifdef CONFIG_LOCKDEP 8016 static LIST_HEAD(net_unlink_list); 8017 8018 static void net_unlink_todo(struct net_device *dev) 8019 { 8020 if (list_empty(&dev->unlink_list)) 8021 list_add_tail(&dev->unlink_list, &net_unlink_list); 8022 } 8023 #endif 8024 8025 static int __netdev_update_lower_level(struct net_device *dev, 8026 struct netdev_nested_priv *priv) 8027 { 8028 dev->lower_level = __netdev_lower_depth(dev) + 1; 8029 8030 #ifdef CONFIG_LOCKDEP 8031 if (!priv) 8032 return 0; 8033 8034 if (priv->flags & NESTED_SYNC_IMM) 8035 dev->nested_level = dev->lower_level - 1; 8036 if (priv->flags & NESTED_SYNC_TODO) 8037 net_unlink_todo(dev); 8038 #endif 8039 return 0; 8040 } 8041 8042 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 8043 int (*fn)(struct net_device *dev, 8044 struct netdev_nested_priv *priv), 8045 struct netdev_nested_priv *priv) 8046 { 8047 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8048 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8049 int ret, cur = 0; 8050 8051 now = dev; 8052 iter = &dev->adj_list.lower; 8053 8054 while (1) { 8055 if (now != dev) { 8056 ret = fn(now, priv); 8057 if (ret) 8058 return ret; 8059 } 8060 8061 next = NULL; 8062 while (1) { 8063 ldev = netdev_next_lower_dev_rcu(now, &iter); 8064 if (!ldev) 8065 break; 8066 8067 next = ldev; 8068 niter = &ldev->adj_list.lower; 8069 dev_stack[cur] = now; 8070 iter_stack[cur++] = iter; 8071 break; 8072 } 8073 8074 if (!next) { 8075 if (!cur) 8076 return 0; 8077 next = dev_stack[--cur]; 8078 niter = iter_stack[cur]; 8079 } 8080 8081 now = next; 8082 iter = niter; 8083 } 8084 8085 return 0; 8086 } 8087 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 8088 8089 /** 8090 * netdev_lower_get_first_private_rcu - Get the first ->private from the 8091 * lower neighbour list, RCU 8092 * variant 8093 * @dev: device 8094 * 8095 * Gets the first netdev_adjacent->private from the dev's lower neighbour 8096 * list. The caller must hold RCU read lock. 8097 */ 8098 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 8099 { 8100 struct netdev_adjacent *lower; 8101 8102 lower = list_first_or_null_rcu(&dev->adj_list.lower, 8103 struct netdev_adjacent, list); 8104 if (lower) 8105 return lower->private; 8106 return NULL; 8107 } 8108 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 8109 8110 /** 8111 * netdev_master_upper_dev_get_rcu - Get master upper device 8112 * @dev: device 8113 * 8114 * Find a master upper device and return pointer to it or NULL in case 8115 * it's not there. The caller must hold the RCU read lock. 8116 */ 8117 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 8118 { 8119 struct netdev_adjacent *upper; 8120 8121 upper = list_first_or_null_rcu(&dev->adj_list.upper, 8122 struct netdev_adjacent, list); 8123 if (upper && likely(upper->master)) 8124 return upper->dev; 8125 return NULL; 8126 } 8127 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 8128 8129 static int netdev_adjacent_sysfs_add(struct net_device *dev, 8130 struct net_device *adj_dev, 8131 struct list_head *dev_list) 8132 { 8133 char linkname[IFNAMSIZ+7]; 8134 8135 sprintf(linkname, dev_list == &dev->adj_list.upper ? 8136 "upper_%s" : "lower_%s", adj_dev->name); 8137 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 8138 linkname); 8139 } 8140 static void netdev_adjacent_sysfs_del(struct net_device *dev, 8141 char *name, 8142 struct list_head *dev_list) 8143 { 8144 char linkname[IFNAMSIZ+7]; 8145 8146 sprintf(linkname, dev_list == &dev->adj_list.upper ? 8147 "upper_%s" : "lower_%s", name); 8148 sysfs_remove_link(&(dev->dev.kobj), linkname); 8149 } 8150 8151 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 8152 struct net_device *adj_dev, 8153 struct list_head *dev_list) 8154 { 8155 return (dev_list == &dev->adj_list.upper || 8156 dev_list == &dev->adj_list.lower) && 8157 net_eq(dev_net(dev), dev_net(adj_dev)); 8158 } 8159 8160 static int __netdev_adjacent_dev_insert(struct net_device *dev, 8161 struct net_device *adj_dev, 8162 struct list_head *dev_list, 8163 void *private, bool master) 8164 { 8165 struct netdev_adjacent *adj; 8166 int ret; 8167 8168 adj = __netdev_find_adj(adj_dev, dev_list); 8169 8170 if (adj) { 8171 adj->ref_nr += 1; 8172 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 8173 dev->name, adj_dev->name, adj->ref_nr); 8174 8175 return 0; 8176 } 8177 8178 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 8179 if (!adj) 8180 return -ENOMEM; 8181 8182 adj->dev = adj_dev; 8183 adj->master = master; 8184 adj->ref_nr = 1; 8185 adj->private = private; 8186 adj->ignore = false; 8187 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 8188 8189 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 8190 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 8191 8192 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 8193 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 8194 if (ret) 8195 goto free_adj; 8196 } 8197 8198 /* Ensure that master link is always the first item in list. */ 8199 if (master) { 8200 ret = sysfs_create_link(&(dev->dev.kobj), 8201 &(adj_dev->dev.kobj), "master"); 8202 if (ret) 8203 goto remove_symlinks; 8204 8205 list_add_rcu(&adj->list, dev_list); 8206 } else { 8207 list_add_tail_rcu(&adj->list, dev_list); 8208 } 8209 8210 return 0; 8211 8212 remove_symlinks: 8213 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 8214 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 8215 free_adj: 8216 netdev_put(adj_dev, &adj->dev_tracker); 8217 kfree(adj); 8218 8219 return ret; 8220 } 8221 8222 static void __netdev_adjacent_dev_remove(struct net_device *dev, 8223 struct net_device *adj_dev, 8224 u16 ref_nr, 8225 struct list_head *dev_list) 8226 { 8227 struct netdev_adjacent *adj; 8228 8229 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 8230 dev->name, adj_dev->name, ref_nr); 8231 8232 adj = __netdev_find_adj(adj_dev, dev_list); 8233 8234 if (!adj) { 8235 pr_err("Adjacency does not exist for device %s from %s\n", 8236 dev->name, adj_dev->name); 8237 WARN_ON(1); 8238 return; 8239 } 8240 8241 if (adj->ref_nr > ref_nr) { 8242 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 8243 dev->name, adj_dev->name, ref_nr, 8244 adj->ref_nr - ref_nr); 8245 adj->ref_nr -= ref_nr; 8246 return; 8247 } 8248 8249 if (adj->master) 8250 sysfs_remove_link(&(dev->dev.kobj), "master"); 8251 8252 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 8253 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 8254 8255 list_del_rcu(&adj->list); 8256 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 8257 adj_dev->name, dev->name, adj_dev->name); 8258 netdev_put(adj_dev, &adj->dev_tracker); 8259 kfree_rcu(adj, rcu); 8260 } 8261 8262 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 8263 struct net_device *upper_dev, 8264 struct list_head *up_list, 8265 struct list_head *down_list, 8266 void *private, bool master) 8267 { 8268 int ret; 8269 8270 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 8271 private, master); 8272 if (ret) 8273 return ret; 8274 8275 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 8276 private, false); 8277 if (ret) { 8278 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 8279 return ret; 8280 } 8281 8282 return 0; 8283 } 8284 8285 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 8286 struct net_device *upper_dev, 8287 u16 ref_nr, 8288 struct list_head *up_list, 8289 struct list_head *down_list) 8290 { 8291 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 8292 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 8293 } 8294 8295 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 8296 struct net_device *upper_dev, 8297 void *private, bool master) 8298 { 8299 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 8300 &dev->adj_list.upper, 8301 &upper_dev->adj_list.lower, 8302 private, master); 8303 } 8304 8305 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 8306 struct net_device *upper_dev) 8307 { 8308 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 8309 &dev->adj_list.upper, 8310 &upper_dev->adj_list.lower); 8311 } 8312 8313 static int __netdev_upper_dev_link(struct net_device *dev, 8314 struct net_device *upper_dev, bool master, 8315 void *upper_priv, void *upper_info, 8316 struct netdev_nested_priv *priv, 8317 struct netlink_ext_ack *extack) 8318 { 8319 struct netdev_notifier_changeupper_info changeupper_info = { 8320 .info = { 8321 .dev = dev, 8322 .extack = extack, 8323 }, 8324 .upper_dev = upper_dev, 8325 .master = master, 8326 .linking = true, 8327 .upper_info = upper_info, 8328 }; 8329 struct net_device *master_dev; 8330 int ret = 0; 8331 8332 ASSERT_RTNL(); 8333 8334 if (dev == upper_dev) 8335 return -EBUSY; 8336 8337 /* To prevent loops, check if dev is not upper device to upper_dev. */ 8338 if (__netdev_has_upper_dev(upper_dev, dev)) 8339 return -EBUSY; 8340 8341 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 8342 return -EMLINK; 8343 8344 if (!master) { 8345 if (__netdev_has_upper_dev(dev, upper_dev)) 8346 return -EEXIST; 8347 } else { 8348 master_dev = __netdev_master_upper_dev_get(dev); 8349 if (master_dev) 8350 return master_dev == upper_dev ? -EEXIST : -EBUSY; 8351 } 8352 8353 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 8354 &changeupper_info.info); 8355 ret = notifier_to_errno(ret); 8356 if (ret) 8357 return ret; 8358 8359 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 8360 master); 8361 if (ret) 8362 return ret; 8363 8364 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 8365 &changeupper_info.info); 8366 ret = notifier_to_errno(ret); 8367 if (ret) 8368 goto rollback; 8369 8370 __netdev_update_upper_level(dev, NULL); 8371 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 8372 8373 __netdev_update_lower_level(upper_dev, priv); 8374 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 8375 priv); 8376 8377 return 0; 8378 8379 rollback: 8380 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 8381 8382 return ret; 8383 } 8384 8385 /** 8386 * netdev_upper_dev_link - Add a link to the upper device 8387 * @dev: device 8388 * @upper_dev: new upper device 8389 * @extack: netlink extended ack 8390 * 8391 * Adds a link to device which is upper to this one. The caller must hold 8392 * the RTNL lock. On a failure a negative errno code is returned. 8393 * On success the reference counts are adjusted and the function 8394 * returns zero. 8395 */ 8396 int netdev_upper_dev_link(struct net_device *dev, 8397 struct net_device *upper_dev, 8398 struct netlink_ext_ack *extack) 8399 { 8400 struct netdev_nested_priv priv = { 8401 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8402 .data = NULL, 8403 }; 8404 8405 return __netdev_upper_dev_link(dev, upper_dev, false, 8406 NULL, NULL, &priv, extack); 8407 } 8408 EXPORT_SYMBOL(netdev_upper_dev_link); 8409 8410 /** 8411 * netdev_master_upper_dev_link - Add a master link to the upper device 8412 * @dev: device 8413 * @upper_dev: new upper device 8414 * @upper_priv: upper device private 8415 * @upper_info: upper info to be passed down via notifier 8416 * @extack: netlink extended ack 8417 * 8418 * Adds a link to device which is upper to this one. In this case, only 8419 * one master upper device can be linked, although other non-master devices 8420 * might be linked as well. The caller must hold the RTNL lock. 8421 * On a failure a negative errno code is returned. On success the reference 8422 * counts are adjusted and the function returns zero. 8423 */ 8424 int netdev_master_upper_dev_link(struct net_device *dev, 8425 struct net_device *upper_dev, 8426 void *upper_priv, void *upper_info, 8427 struct netlink_ext_ack *extack) 8428 { 8429 struct netdev_nested_priv priv = { 8430 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8431 .data = NULL, 8432 }; 8433 8434 return __netdev_upper_dev_link(dev, upper_dev, true, 8435 upper_priv, upper_info, &priv, extack); 8436 } 8437 EXPORT_SYMBOL(netdev_master_upper_dev_link); 8438 8439 static void __netdev_upper_dev_unlink(struct net_device *dev, 8440 struct net_device *upper_dev, 8441 struct netdev_nested_priv *priv) 8442 { 8443 struct netdev_notifier_changeupper_info changeupper_info = { 8444 .info = { 8445 .dev = dev, 8446 }, 8447 .upper_dev = upper_dev, 8448 .linking = false, 8449 }; 8450 8451 ASSERT_RTNL(); 8452 8453 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 8454 8455 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 8456 &changeupper_info.info); 8457 8458 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 8459 8460 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 8461 &changeupper_info.info); 8462 8463 __netdev_update_upper_level(dev, NULL); 8464 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 8465 8466 __netdev_update_lower_level(upper_dev, priv); 8467 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 8468 priv); 8469 } 8470 8471 /** 8472 * netdev_upper_dev_unlink - Removes a link to upper device 8473 * @dev: device 8474 * @upper_dev: new upper device 8475 * 8476 * Removes a link to device which is upper to this one. The caller must hold 8477 * the RTNL lock. 8478 */ 8479 void netdev_upper_dev_unlink(struct net_device *dev, 8480 struct net_device *upper_dev) 8481 { 8482 struct netdev_nested_priv priv = { 8483 .flags = NESTED_SYNC_TODO, 8484 .data = NULL, 8485 }; 8486 8487 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 8488 } 8489 EXPORT_SYMBOL(netdev_upper_dev_unlink); 8490 8491 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 8492 struct net_device *lower_dev, 8493 bool val) 8494 { 8495 struct netdev_adjacent *adj; 8496 8497 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 8498 if (adj) 8499 adj->ignore = val; 8500 8501 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 8502 if (adj) 8503 adj->ignore = val; 8504 } 8505 8506 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 8507 struct net_device *lower_dev) 8508 { 8509 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 8510 } 8511 8512 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 8513 struct net_device *lower_dev) 8514 { 8515 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 8516 } 8517 8518 int netdev_adjacent_change_prepare(struct net_device *old_dev, 8519 struct net_device *new_dev, 8520 struct net_device *dev, 8521 struct netlink_ext_ack *extack) 8522 { 8523 struct netdev_nested_priv priv = { 8524 .flags = 0, 8525 .data = NULL, 8526 }; 8527 int err; 8528 8529 if (!new_dev) 8530 return 0; 8531 8532 if (old_dev && new_dev != old_dev) 8533 netdev_adjacent_dev_disable(dev, old_dev); 8534 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 8535 extack); 8536 if (err) { 8537 if (old_dev && new_dev != old_dev) 8538 netdev_adjacent_dev_enable(dev, old_dev); 8539 return err; 8540 } 8541 8542 return 0; 8543 } 8544 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 8545 8546 void netdev_adjacent_change_commit(struct net_device *old_dev, 8547 struct net_device *new_dev, 8548 struct net_device *dev) 8549 { 8550 struct netdev_nested_priv priv = { 8551 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8552 .data = NULL, 8553 }; 8554 8555 if (!new_dev || !old_dev) 8556 return; 8557 8558 if (new_dev == old_dev) 8559 return; 8560 8561 netdev_adjacent_dev_enable(dev, old_dev); 8562 __netdev_upper_dev_unlink(old_dev, dev, &priv); 8563 } 8564 EXPORT_SYMBOL(netdev_adjacent_change_commit); 8565 8566 void netdev_adjacent_change_abort(struct net_device *old_dev, 8567 struct net_device *new_dev, 8568 struct net_device *dev) 8569 { 8570 struct netdev_nested_priv priv = { 8571 .flags = 0, 8572 .data = NULL, 8573 }; 8574 8575 if (!new_dev) 8576 return; 8577 8578 if (old_dev && new_dev != old_dev) 8579 netdev_adjacent_dev_enable(dev, old_dev); 8580 8581 __netdev_upper_dev_unlink(new_dev, dev, &priv); 8582 } 8583 EXPORT_SYMBOL(netdev_adjacent_change_abort); 8584 8585 /** 8586 * netdev_bonding_info_change - Dispatch event about slave change 8587 * @dev: device 8588 * @bonding_info: info to dispatch 8589 * 8590 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 8591 * The caller must hold the RTNL lock. 8592 */ 8593 void netdev_bonding_info_change(struct net_device *dev, 8594 struct netdev_bonding_info *bonding_info) 8595 { 8596 struct netdev_notifier_bonding_info info = { 8597 .info.dev = dev, 8598 }; 8599 8600 memcpy(&info.bonding_info, bonding_info, 8601 sizeof(struct netdev_bonding_info)); 8602 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 8603 &info.info); 8604 } 8605 EXPORT_SYMBOL(netdev_bonding_info_change); 8606 8607 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 8608 struct netlink_ext_ack *extack) 8609 { 8610 struct netdev_notifier_offload_xstats_info info = { 8611 .info.dev = dev, 8612 .info.extack = extack, 8613 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 8614 }; 8615 int err; 8616 int rc; 8617 8618 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 8619 GFP_KERNEL); 8620 if (!dev->offload_xstats_l3) 8621 return -ENOMEM; 8622 8623 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 8624 NETDEV_OFFLOAD_XSTATS_DISABLE, 8625 &info.info); 8626 err = notifier_to_errno(rc); 8627 if (err) 8628 goto free_stats; 8629 8630 return 0; 8631 8632 free_stats: 8633 kfree(dev->offload_xstats_l3); 8634 dev->offload_xstats_l3 = NULL; 8635 return err; 8636 } 8637 8638 int netdev_offload_xstats_enable(struct net_device *dev, 8639 enum netdev_offload_xstats_type type, 8640 struct netlink_ext_ack *extack) 8641 { 8642 ASSERT_RTNL(); 8643 8644 if (netdev_offload_xstats_enabled(dev, type)) 8645 return -EALREADY; 8646 8647 switch (type) { 8648 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8649 return netdev_offload_xstats_enable_l3(dev, extack); 8650 } 8651 8652 WARN_ON(1); 8653 return -EINVAL; 8654 } 8655 EXPORT_SYMBOL(netdev_offload_xstats_enable); 8656 8657 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 8658 { 8659 struct netdev_notifier_offload_xstats_info info = { 8660 .info.dev = dev, 8661 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 8662 }; 8663 8664 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 8665 &info.info); 8666 kfree(dev->offload_xstats_l3); 8667 dev->offload_xstats_l3 = NULL; 8668 } 8669 8670 int netdev_offload_xstats_disable(struct net_device *dev, 8671 enum netdev_offload_xstats_type type) 8672 { 8673 ASSERT_RTNL(); 8674 8675 if (!netdev_offload_xstats_enabled(dev, type)) 8676 return -EALREADY; 8677 8678 switch (type) { 8679 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8680 netdev_offload_xstats_disable_l3(dev); 8681 return 0; 8682 } 8683 8684 WARN_ON(1); 8685 return -EINVAL; 8686 } 8687 EXPORT_SYMBOL(netdev_offload_xstats_disable); 8688 8689 static void netdev_offload_xstats_disable_all(struct net_device *dev) 8690 { 8691 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 8692 } 8693 8694 static struct rtnl_hw_stats64 * 8695 netdev_offload_xstats_get_ptr(const struct net_device *dev, 8696 enum netdev_offload_xstats_type type) 8697 { 8698 switch (type) { 8699 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8700 return dev->offload_xstats_l3; 8701 } 8702 8703 WARN_ON(1); 8704 return NULL; 8705 } 8706 8707 bool netdev_offload_xstats_enabled(const struct net_device *dev, 8708 enum netdev_offload_xstats_type type) 8709 { 8710 ASSERT_RTNL(); 8711 8712 return netdev_offload_xstats_get_ptr(dev, type); 8713 } 8714 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 8715 8716 struct netdev_notifier_offload_xstats_ru { 8717 bool used; 8718 }; 8719 8720 struct netdev_notifier_offload_xstats_rd { 8721 struct rtnl_hw_stats64 stats; 8722 bool used; 8723 }; 8724 8725 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 8726 const struct rtnl_hw_stats64 *src) 8727 { 8728 dest->rx_packets += src->rx_packets; 8729 dest->tx_packets += src->tx_packets; 8730 dest->rx_bytes += src->rx_bytes; 8731 dest->tx_bytes += src->tx_bytes; 8732 dest->rx_errors += src->rx_errors; 8733 dest->tx_errors += src->tx_errors; 8734 dest->rx_dropped += src->rx_dropped; 8735 dest->tx_dropped += src->tx_dropped; 8736 dest->multicast += src->multicast; 8737 } 8738 8739 static int netdev_offload_xstats_get_used(struct net_device *dev, 8740 enum netdev_offload_xstats_type type, 8741 bool *p_used, 8742 struct netlink_ext_ack *extack) 8743 { 8744 struct netdev_notifier_offload_xstats_ru report_used = {}; 8745 struct netdev_notifier_offload_xstats_info info = { 8746 .info.dev = dev, 8747 .info.extack = extack, 8748 .type = type, 8749 .report_used = &report_used, 8750 }; 8751 int rc; 8752 8753 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8754 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8755 &info.info); 8756 *p_used = report_used.used; 8757 return notifier_to_errno(rc); 8758 } 8759 8760 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8761 enum netdev_offload_xstats_type type, 8762 struct rtnl_hw_stats64 *p_stats, 8763 bool *p_used, 8764 struct netlink_ext_ack *extack) 8765 { 8766 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8767 struct netdev_notifier_offload_xstats_info info = { 8768 .info.dev = dev, 8769 .info.extack = extack, 8770 .type = type, 8771 .report_delta = &report_delta, 8772 }; 8773 struct rtnl_hw_stats64 *stats; 8774 int rc; 8775 8776 stats = netdev_offload_xstats_get_ptr(dev, type); 8777 if (WARN_ON(!stats)) 8778 return -EINVAL; 8779 8780 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8781 &info.info); 8782 8783 /* Cache whatever we got, even if there was an error, otherwise the 8784 * successful stats retrievals would get lost. 8785 */ 8786 netdev_hw_stats64_add(stats, &report_delta.stats); 8787 8788 if (p_stats) 8789 *p_stats = *stats; 8790 *p_used = report_delta.used; 8791 8792 return notifier_to_errno(rc); 8793 } 8794 8795 int netdev_offload_xstats_get(struct net_device *dev, 8796 enum netdev_offload_xstats_type type, 8797 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8798 struct netlink_ext_ack *extack) 8799 { 8800 ASSERT_RTNL(); 8801 8802 if (p_stats) 8803 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8804 p_used, extack); 8805 else 8806 return netdev_offload_xstats_get_used(dev, type, p_used, 8807 extack); 8808 } 8809 EXPORT_SYMBOL(netdev_offload_xstats_get); 8810 8811 void 8812 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8813 const struct rtnl_hw_stats64 *stats) 8814 { 8815 report_delta->used = true; 8816 netdev_hw_stats64_add(&report_delta->stats, stats); 8817 } 8818 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8819 8820 void 8821 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8822 { 8823 report_used->used = true; 8824 } 8825 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8826 8827 void netdev_offload_xstats_push_delta(struct net_device *dev, 8828 enum netdev_offload_xstats_type type, 8829 const struct rtnl_hw_stats64 *p_stats) 8830 { 8831 struct rtnl_hw_stats64 *stats; 8832 8833 ASSERT_RTNL(); 8834 8835 stats = netdev_offload_xstats_get_ptr(dev, type); 8836 if (WARN_ON(!stats)) 8837 return; 8838 8839 netdev_hw_stats64_add(stats, p_stats); 8840 } 8841 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8842 8843 /** 8844 * netdev_get_xmit_slave - Get the xmit slave of master device 8845 * @dev: device 8846 * @skb: The packet 8847 * @all_slaves: assume all the slaves are active 8848 * 8849 * The reference counters are not incremented so the caller must be 8850 * careful with locks. The caller must hold RCU lock. 8851 * %NULL is returned if no slave is found. 8852 */ 8853 8854 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8855 struct sk_buff *skb, 8856 bool all_slaves) 8857 { 8858 const struct net_device_ops *ops = dev->netdev_ops; 8859 8860 if (!ops->ndo_get_xmit_slave) 8861 return NULL; 8862 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8863 } 8864 EXPORT_SYMBOL(netdev_get_xmit_slave); 8865 8866 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8867 struct sock *sk) 8868 { 8869 const struct net_device_ops *ops = dev->netdev_ops; 8870 8871 if (!ops->ndo_sk_get_lower_dev) 8872 return NULL; 8873 return ops->ndo_sk_get_lower_dev(dev, sk); 8874 } 8875 8876 /** 8877 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8878 * @dev: device 8879 * @sk: the socket 8880 * 8881 * %NULL is returned if no lower device is found. 8882 */ 8883 8884 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8885 struct sock *sk) 8886 { 8887 struct net_device *lower; 8888 8889 lower = netdev_sk_get_lower_dev(dev, sk); 8890 while (lower) { 8891 dev = lower; 8892 lower = netdev_sk_get_lower_dev(dev, sk); 8893 } 8894 8895 return dev; 8896 } 8897 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8898 8899 static void netdev_adjacent_add_links(struct net_device *dev) 8900 { 8901 struct netdev_adjacent *iter; 8902 8903 struct net *net = dev_net(dev); 8904 8905 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8906 if (!net_eq(net, dev_net(iter->dev))) 8907 continue; 8908 netdev_adjacent_sysfs_add(iter->dev, dev, 8909 &iter->dev->adj_list.lower); 8910 netdev_adjacent_sysfs_add(dev, iter->dev, 8911 &dev->adj_list.upper); 8912 } 8913 8914 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8915 if (!net_eq(net, dev_net(iter->dev))) 8916 continue; 8917 netdev_adjacent_sysfs_add(iter->dev, dev, 8918 &iter->dev->adj_list.upper); 8919 netdev_adjacent_sysfs_add(dev, iter->dev, 8920 &dev->adj_list.lower); 8921 } 8922 } 8923 8924 static void netdev_adjacent_del_links(struct net_device *dev) 8925 { 8926 struct netdev_adjacent *iter; 8927 8928 struct net *net = dev_net(dev); 8929 8930 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8931 if (!net_eq(net, dev_net(iter->dev))) 8932 continue; 8933 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8934 &iter->dev->adj_list.lower); 8935 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8936 &dev->adj_list.upper); 8937 } 8938 8939 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8940 if (!net_eq(net, dev_net(iter->dev))) 8941 continue; 8942 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8943 &iter->dev->adj_list.upper); 8944 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8945 &dev->adj_list.lower); 8946 } 8947 } 8948 8949 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8950 { 8951 struct netdev_adjacent *iter; 8952 8953 struct net *net = dev_net(dev); 8954 8955 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8956 if (!net_eq(net, dev_net(iter->dev))) 8957 continue; 8958 netdev_adjacent_sysfs_del(iter->dev, oldname, 8959 &iter->dev->adj_list.lower); 8960 netdev_adjacent_sysfs_add(iter->dev, dev, 8961 &iter->dev->adj_list.lower); 8962 } 8963 8964 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8965 if (!net_eq(net, dev_net(iter->dev))) 8966 continue; 8967 netdev_adjacent_sysfs_del(iter->dev, oldname, 8968 &iter->dev->adj_list.upper); 8969 netdev_adjacent_sysfs_add(iter->dev, dev, 8970 &iter->dev->adj_list.upper); 8971 } 8972 } 8973 8974 void *netdev_lower_dev_get_private(struct net_device *dev, 8975 struct net_device *lower_dev) 8976 { 8977 struct netdev_adjacent *lower; 8978 8979 if (!lower_dev) 8980 return NULL; 8981 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8982 if (!lower) 8983 return NULL; 8984 8985 return lower->private; 8986 } 8987 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8988 8989 8990 /** 8991 * netdev_lower_state_changed - Dispatch event about lower device state change 8992 * @lower_dev: device 8993 * @lower_state_info: state to dispatch 8994 * 8995 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8996 * The caller must hold the RTNL lock. 8997 */ 8998 void netdev_lower_state_changed(struct net_device *lower_dev, 8999 void *lower_state_info) 9000 { 9001 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 9002 .info.dev = lower_dev, 9003 }; 9004 9005 ASSERT_RTNL(); 9006 changelowerstate_info.lower_state_info = lower_state_info; 9007 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 9008 &changelowerstate_info.info); 9009 } 9010 EXPORT_SYMBOL(netdev_lower_state_changed); 9011 9012 static void dev_change_rx_flags(struct net_device *dev, int flags) 9013 { 9014 const struct net_device_ops *ops = dev->netdev_ops; 9015 9016 if (ops->ndo_change_rx_flags) 9017 ops->ndo_change_rx_flags(dev, flags); 9018 } 9019 9020 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 9021 { 9022 unsigned int old_flags = dev->flags; 9023 unsigned int promiscuity, flags; 9024 kuid_t uid; 9025 kgid_t gid; 9026 9027 ASSERT_RTNL(); 9028 9029 promiscuity = dev->promiscuity + inc; 9030 if (promiscuity == 0) { 9031 /* 9032 * Avoid overflow. 9033 * If inc causes overflow, untouch promisc and return error. 9034 */ 9035 if (unlikely(inc > 0)) { 9036 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 9037 return -EOVERFLOW; 9038 } 9039 flags = old_flags & ~IFF_PROMISC; 9040 } else { 9041 flags = old_flags | IFF_PROMISC; 9042 } 9043 WRITE_ONCE(dev->promiscuity, promiscuity); 9044 if (flags != old_flags) { 9045 WRITE_ONCE(dev->flags, flags); 9046 netdev_info(dev, "%s promiscuous mode\n", 9047 dev->flags & IFF_PROMISC ? "entered" : "left"); 9048 if (audit_enabled) { 9049 current_uid_gid(&uid, &gid); 9050 audit_log(audit_context(), GFP_ATOMIC, 9051 AUDIT_ANOM_PROMISCUOUS, 9052 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 9053 dev->name, (dev->flags & IFF_PROMISC), 9054 (old_flags & IFF_PROMISC), 9055 from_kuid(&init_user_ns, audit_get_loginuid(current)), 9056 from_kuid(&init_user_ns, uid), 9057 from_kgid(&init_user_ns, gid), 9058 audit_get_sessionid(current)); 9059 } 9060 9061 dev_change_rx_flags(dev, IFF_PROMISC); 9062 } 9063 if (notify) 9064 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 9065 return 0; 9066 } 9067 9068 /** 9069 * dev_set_promiscuity - update promiscuity count on a device 9070 * @dev: device 9071 * @inc: modifier 9072 * 9073 * Add or remove promiscuity from a device. While the count in the device 9074 * remains above zero the interface remains promiscuous. Once it hits zero 9075 * the device reverts back to normal filtering operation. A negative inc 9076 * value is used to drop promiscuity on the device. 9077 * Return 0 if successful or a negative errno code on error. 9078 */ 9079 int dev_set_promiscuity(struct net_device *dev, int inc) 9080 { 9081 unsigned int old_flags = dev->flags; 9082 int err; 9083 9084 err = __dev_set_promiscuity(dev, inc, true); 9085 if (err < 0) 9086 return err; 9087 if (dev->flags != old_flags) 9088 dev_set_rx_mode(dev); 9089 return err; 9090 } 9091 EXPORT_SYMBOL(dev_set_promiscuity); 9092 9093 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 9094 { 9095 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 9096 unsigned int allmulti, flags; 9097 9098 ASSERT_RTNL(); 9099 9100 allmulti = dev->allmulti + inc; 9101 if (allmulti == 0) { 9102 /* 9103 * Avoid overflow. 9104 * If inc causes overflow, untouch allmulti and return error. 9105 */ 9106 if (unlikely(inc > 0)) { 9107 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 9108 return -EOVERFLOW; 9109 } 9110 flags = old_flags & ~IFF_ALLMULTI; 9111 } else { 9112 flags = old_flags | IFF_ALLMULTI; 9113 } 9114 WRITE_ONCE(dev->allmulti, allmulti); 9115 if (flags != old_flags) { 9116 WRITE_ONCE(dev->flags, flags); 9117 netdev_info(dev, "%s allmulticast mode\n", 9118 dev->flags & IFF_ALLMULTI ? "entered" : "left"); 9119 dev_change_rx_flags(dev, IFF_ALLMULTI); 9120 dev_set_rx_mode(dev); 9121 if (notify) 9122 __dev_notify_flags(dev, old_flags, 9123 dev->gflags ^ old_gflags, 0, NULL); 9124 } 9125 return 0; 9126 } 9127 9128 /** 9129 * dev_set_allmulti - update allmulti count on a device 9130 * @dev: device 9131 * @inc: modifier 9132 * 9133 * Add or remove reception of all multicast frames to a device. While the 9134 * count in the device remains above zero the interface remains listening 9135 * to all interfaces. Once it hits zero the device reverts back to normal 9136 * filtering operation. A negative @inc value is used to drop the counter 9137 * when releasing a resource needing all multicasts. 9138 * Return 0 if successful or a negative errno code on error. 9139 */ 9140 9141 int dev_set_allmulti(struct net_device *dev, int inc) 9142 { 9143 return __dev_set_allmulti(dev, inc, true); 9144 } 9145 EXPORT_SYMBOL(dev_set_allmulti); 9146 9147 /* 9148 * Upload unicast and multicast address lists to device and 9149 * configure RX filtering. When the device doesn't support unicast 9150 * filtering it is put in promiscuous mode while unicast addresses 9151 * are present. 9152 */ 9153 void __dev_set_rx_mode(struct net_device *dev) 9154 { 9155 const struct net_device_ops *ops = dev->netdev_ops; 9156 9157 /* dev_open will call this function so the list will stay sane. */ 9158 if (!(dev->flags&IFF_UP)) 9159 return; 9160 9161 if (!netif_device_present(dev)) 9162 return; 9163 9164 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 9165 /* Unicast addresses changes may only happen under the rtnl, 9166 * therefore calling __dev_set_promiscuity here is safe. 9167 */ 9168 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 9169 __dev_set_promiscuity(dev, 1, false); 9170 dev->uc_promisc = true; 9171 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 9172 __dev_set_promiscuity(dev, -1, false); 9173 dev->uc_promisc = false; 9174 } 9175 } 9176 9177 if (ops->ndo_set_rx_mode) 9178 ops->ndo_set_rx_mode(dev); 9179 } 9180 9181 void dev_set_rx_mode(struct net_device *dev) 9182 { 9183 netif_addr_lock_bh(dev); 9184 __dev_set_rx_mode(dev); 9185 netif_addr_unlock_bh(dev); 9186 } 9187 9188 /** 9189 * dev_get_flags - get flags reported to userspace 9190 * @dev: device 9191 * 9192 * Get the combination of flag bits exported through APIs to userspace. 9193 */ 9194 unsigned int dev_get_flags(const struct net_device *dev) 9195 { 9196 unsigned int flags; 9197 9198 flags = (READ_ONCE(dev->flags) & ~(IFF_PROMISC | 9199 IFF_ALLMULTI | 9200 IFF_RUNNING | 9201 IFF_LOWER_UP | 9202 IFF_DORMANT)) | 9203 (READ_ONCE(dev->gflags) & (IFF_PROMISC | 9204 IFF_ALLMULTI)); 9205 9206 if (netif_running(dev)) { 9207 if (netif_oper_up(dev)) 9208 flags |= IFF_RUNNING; 9209 if (netif_carrier_ok(dev)) 9210 flags |= IFF_LOWER_UP; 9211 if (netif_dormant(dev)) 9212 flags |= IFF_DORMANT; 9213 } 9214 9215 return flags; 9216 } 9217 EXPORT_SYMBOL(dev_get_flags); 9218 9219 int __dev_change_flags(struct net_device *dev, unsigned int flags, 9220 struct netlink_ext_ack *extack) 9221 { 9222 unsigned int old_flags = dev->flags; 9223 int ret; 9224 9225 ASSERT_RTNL(); 9226 9227 /* 9228 * Set the flags on our device. 9229 */ 9230 9231 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 9232 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 9233 IFF_AUTOMEDIA)) | 9234 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 9235 IFF_ALLMULTI)); 9236 9237 /* 9238 * Load in the correct multicast list now the flags have changed. 9239 */ 9240 9241 if ((old_flags ^ flags) & IFF_MULTICAST) 9242 dev_change_rx_flags(dev, IFF_MULTICAST); 9243 9244 dev_set_rx_mode(dev); 9245 9246 /* 9247 * Have we downed the interface. We handle IFF_UP ourselves 9248 * according to user attempts to set it, rather than blindly 9249 * setting it. 9250 */ 9251 9252 ret = 0; 9253 if ((old_flags ^ flags) & IFF_UP) { 9254 if (old_flags & IFF_UP) 9255 __dev_close(dev); 9256 else 9257 ret = __dev_open(dev, extack); 9258 } 9259 9260 if ((flags ^ dev->gflags) & IFF_PROMISC) { 9261 int inc = (flags & IFF_PROMISC) ? 1 : -1; 9262 unsigned int old_flags = dev->flags; 9263 9264 dev->gflags ^= IFF_PROMISC; 9265 9266 if (__dev_set_promiscuity(dev, inc, false) >= 0) 9267 if (dev->flags != old_flags) 9268 dev_set_rx_mode(dev); 9269 } 9270 9271 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 9272 * is important. Some (broken) drivers set IFF_PROMISC, when 9273 * IFF_ALLMULTI is requested not asking us and not reporting. 9274 */ 9275 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 9276 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 9277 9278 dev->gflags ^= IFF_ALLMULTI; 9279 __dev_set_allmulti(dev, inc, false); 9280 } 9281 9282 return ret; 9283 } 9284 9285 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 9286 unsigned int gchanges, u32 portid, 9287 const struct nlmsghdr *nlh) 9288 { 9289 unsigned int changes = dev->flags ^ old_flags; 9290 9291 if (gchanges) 9292 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 9293 9294 if (changes & IFF_UP) { 9295 if (dev->flags & IFF_UP) 9296 call_netdevice_notifiers(NETDEV_UP, dev); 9297 else 9298 call_netdevice_notifiers(NETDEV_DOWN, dev); 9299 } 9300 9301 if (dev->flags & IFF_UP && 9302 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 9303 struct netdev_notifier_change_info change_info = { 9304 .info = { 9305 .dev = dev, 9306 }, 9307 .flags_changed = changes, 9308 }; 9309 9310 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 9311 } 9312 } 9313 9314 /** 9315 * dev_change_flags - change device settings 9316 * @dev: device 9317 * @flags: device state flags 9318 * @extack: netlink extended ack 9319 * 9320 * Change settings on device based state flags. The flags are 9321 * in the userspace exported format. 9322 */ 9323 int dev_change_flags(struct net_device *dev, unsigned int flags, 9324 struct netlink_ext_ack *extack) 9325 { 9326 int ret; 9327 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 9328 9329 ret = __dev_change_flags(dev, flags, extack); 9330 if (ret < 0) 9331 return ret; 9332 9333 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 9334 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 9335 return ret; 9336 } 9337 EXPORT_SYMBOL(dev_change_flags); 9338 9339 int __dev_set_mtu(struct net_device *dev, int new_mtu) 9340 { 9341 const struct net_device_ops *ops = dev->netdev_ops; 9342 9343 if (ops->ndo_change_mtu) 9344 return ops->ndo_change_mtu(dev, new_mtu); 9345 9346 /* Pairs with all the lockless reads of dev->mtu in the stack */ 9347 WRITE_ONCE(dev->mtu, new_mtu); 9348 return 0; 9349 } 9350 EXPORT_SYMBOL(__dev_set_mtu); 9351 9352 int dev_validate_mtu(struct net_device *dev, int new_mtu, 9353 struct netlink_ext_ack *extack) 9354 { 9355 /* MTU must be positive, and in range */ 9356 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 9357 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 9358 return -EINVAL; 9359 } 9360 9361 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 9362 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 9363 return -EINVAL; 9364 } 9365 return 0; 9366 } 9367 9368 /** 9369 * dev_set_mtu_ext - Change maximum transfer unit 9370 * @dev: device 9371 * @new_mtu: new transfer unit 9372 * @extack: netlink extended ack 9373 * 9374 * Change the maximum transfer size of the network device. 9375 */ 9376 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 9377 struct netlink_ext_ack *extack) 9378 { 9379 int err, orig_mtu; 9380 9381 if (new_mtu == dev->mtu) 9382 return 0; 9383 9384 err = dev_validate_mtu(dev, new_mtu, extack); 9385 if (err) 9386 return err; 9387 9388 if (!netif_device_present(dev)) 9389 return -ENODEV; 9390 9391 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 9392 err = notifier_to_errno(err); 9393 if (err) 9394 return err; 9395 9396 orig_mtu = dev->mtu; 9397 err = __dev_set_mtu(dev, new_mtu); 9398 9399 if (!err) { 9400 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 9401 orig_mtu); 9402 err = notifier_to_errno(err); 9403 if (err) { 9404 /* setting mtu back and notifying everyone again, 9405 * so that they have a chance to revert changes. 9406 */ 9407 __dev_set_mtu(dev, orig_mtu); 9408 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 9409 new_mtu); 9410 } 9411 } 9412 return err; 9413 } 9414 9415 int dev_set_mtu(struct net_device *dev, int new_mtu) 9416 { 9417 struct netlink_ext_ack extack; 9418 int err; 9419 9420 memset(&extack, 0, sizeof(extack)); 9421 err = dev_set_mtu_ext(dev, new_mtu, &extack); 9422 if (err && extack._msg) 9423 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 9424 return err; 9425 } 9426 EXPORT_SYMBOL(dev_set_mtu); 9427 9428 /** 9429 * dev_change_tx_queue_len - Change TX queue length of a netdevice 9430 * @dev: device 9431 * @new_len: new tx queue length 9432 */ 9433 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 9434 { 9435 unsigned int orig_len = dev->tx_queue_len; 9436 int res; 9437 9438 if (new_len != (unsigned int)new_len) 9439 return -ERANGE; 9440 9441 if (new_len != orig_len) { 9442 WRITE_ONCE(dev->tx_queue_len, new_len); 9443 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 9444 res = notifier_to_errno(res); 9445 if (res) 9446 goto err_rollback; 9447 res = dev_qdisc_change_tx_queue_len(dev); 9448 if (res) 9449 goto err_rollback; 9450 } 9451 9452 return 0; 9453 9454 err_rollback: 9455 netdev_err(dev, "refused to change device tx_queue_len\n"); 9456 WRITE_ONCE(dev->tx_queue_len, orig_len); 9457 return res; 9458 } 9459 9460 /** 9461 * dev_set_group - Change group this device belongs to 9462 * @dev: device 9463 * @new_group: group this device should belong to 9464 */ 9465 void dev_set_group(struct net_device *dev, int new_group) 9466 { 9467 dev->group = new_group; 9468 } 9469 9470 /** 9471 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 9472 * @dev: device 9473 * @addr: new address 9474 * @extack: netlink extended ack 9475 */ 9476 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 9477 struct netlink_ext_ack *extack) 9478 { 9479 struct netdev_notifier_pre_changeaddr_info info = { 9480 .info.dev = dev, 9481 .info.extack = extack, 9482 .dev_addr = addr, 9483 }; 9484 int rc; 9485 9486 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 9487 return notifier_to_errno(rc); 9488 } 9489 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 9490 9491 /** 9492 * dev_set_mac_address - Change Media Access Control Address 9493 * @dev: device 9494 * @sa: new address 9495 * @extack: netlink extended ack 9496 * 9497 * Change the hardware (MAC) address of the device 9498 */ 9499 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 9500 struct netlink_ext_ack *extack) 9501 { 9502 const struct net_device_ops *ops = dev->netdev_ops; 9503 int err; 9504 9505 if (!ops->ndo_set_mac_address) 9506 return -EOPNOTSUPP; 9507 if (sa->sa_family != dev->type) 9508 return -EINVAL; 9509 if (!netif_device_present(dev)) 9510 return -ENODEV; 9511 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 9512 if (err) 9513 return err; 9514 if (memcmp(dev->dev_addr, sa->sa_data, dev->addr_len)) { 9515 err = ops->ndo_set_mac_address(dev, sa); 9516 if (err) 9517 return err; 9518 } 9519 dev->addr_assign_type = NET_ADDR_SET; 9520 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 9521 add_device_randomness(dev->dev_addr, dev->addr_len); 9522 return 0; 9523 } 9524 EXPORT_SYMBOL(dev_set_mac_address); 9525 9526 DECLARE_RWSEM(dev_addr_sem); 9527 9528 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 9529 struct netlink_ext_ack *extack) 9530 { 9531 int ret; 9532 9533 down_write(&dev_addr_sem); 9534 ret = dev_set_mac_address(dev, sa, extack); 9535 up_write(&dev_addr_sem); 9536 return ret; 9537 } 9538 EXPORT_SYMBOL(dev_set_mac_address_user); 9539 9540 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 9541 { 9542 size_t size = sizeof(sa->sa_data_min); 9543 struct net_device *dev; 9544 int ret = 0; 9545 9546 down_read(&dev_addr_sem); 9547 rcu_read_lock(); 9548 9549 dev = dev_get_by_name_rcu(net, dev_name); 9550 if (!dev) { 9551 ret = -ENODEV; 9552 goto unlock; 9553 } 9554 if (!dev->addr_len) 9555 memset(sa->sa_data, 0, size); 9556 else 9557 memcpy(sa->sa_data, dev->dev_addr, 9558 min_t(size_t, size, dev->addr_len)); 9559 sa->sa_family = dev->type; 9560 9561 unlock: 9562 rcu_read_unlock(); 9563 up_read(&dev_addr_sem); 9564 return ret; 9565 } 9566 EXPORT_SYMBOL(dev_get_mac_address); 9567 9568 /** 9569 * dev_change_carrier - Change device carrier 9570 * @dev: device 9571 * @new_carrier: new value 9572 * 9573 * Change device carrier 9574 */ 9575 int dev_change_carrier(struct net_device *dev, bool new_carrier) 9576 { 9577 const struct net_device_ops *ops = dev->netdev_ops; 9578 9579 if (!ops->ndo_change_carrier) 9580 return -EOPNOTSUPP; 9581 if (!netif_device_present(dev)) 9582 return -ENODEV; 9583 return ops->ndo_change_carrier(dev, new_carrier); 9584 } 9585 9586 /** 9587 * dev_get_phys_port_id - Get device physical port ID 9588 * @dev: device 9589 * @ppid: port ID 9590 * 9591 * Get device physical port ID 9592 */ 9593 int dev_get_phys_port_id(struct net_device *dev, 9594 struct netdev_phys_item_id *ppid) 9595 { 9596 const struct net_device_ops *ops = dev->netdev_ops; 9597 9598 if (!ops->ndo_get_phys_port_id) 9599 return -EOPNOTSUPP; 9600 return ops->ndo_get_phys_port_id(dev, ppid); 9601 } 9602 9603 /** 9604 * dev_get_phys_port_name - Get device physical port name 9605 * @dev: device 9606 * @name: port name 9607 * @len: limit of bytes to copy to name 9608 * 9609 * Get device physical port name 9610 */ 9611 int dev_get_phys_port_name(struct net_device *dev, 9612 char *name, size_t len) 9613 { 9614 const struct net_device_ops *ops = dev->netdev_ops; 9615 int err; 9616 9617 if (ops->ndo_get_phys_port_name) { 9618 err = ops->ndo_get_phys_port_name(dev, name, len); 9619 if (err != -EOPNOTSUPP) 9620 return err; 9621 } 9622 return devlink_compat_phys_port_name_get(dev, name, len); 9623 } 9624 9625 /** 9626 * dev_get_port_parent_id - Get the device's port parent identifier 9627 * @dev: network device 9628 * @ppid: pointer to a storage for the port's parent identifier 9629 * @recurse: allow/disallow recursion to lower devices 9630 * 9631 * Get the devices's port parent identifier 9632 */ 9633 int dev_get_port_parent_id(struct net_device *dev, 9634 struct netdev_phys_item_id *ppid, 9635 bool recurse) 9636 { 9637 const struct net_device_ops *ops = dev->netdev_ops; 9638 struct netdev_phys_item_id first = { }; 9639 struct net_device *lower_dev; 9640 struct list_head *iter; 9641 int err; 9642 9643 if (ops->ndo_get_port_parent_id) { 9644 err = ops->ndo_get_port_parent_id(dev, ppid); 9645 if (err != -EOPNOTSUPP) 9646 return err; 9647 } 9648 9649 err = devlink_compat_switch_id_get(dev, ppid); 9650 if (!recurse || err != -EOPNOTSUPP) 9651 return err; 9652 9653 netdev_for_each_lower_dev(dev, lower_dev, iter) { 9654 err = dev_get_port_parent_id(lower_dev, ppid, true); 9655 if (err) 9656 break; 9657 if (!first.id_len) 9658 first = *ppid; 9659 else if (memcmp(&first, ppid, sizeof(*ppid))) 9660 return -EOPNOTSUPP; 9661 } 9662 9663 return err; 9664 } 9665 EXPORT_SYMBOL(dev_get_port_parent_id); 9666 9667 /** 9668 * netdev_port_same_parent_id - Indicate if two network devices have 9669 * the same port parent identifier 9670 * @a: first network device 9671 * @b: second network device 9672 */ 9673 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 9674 { 9675 struct netdev_phys_item_id a_id = { }; 9676 struct netdev_phys_item_id b_id = { }; 9677 9678 if (dev_get_port_parent_id(a, &a_id, true) || 9679 dev_get_port_parent_id(b, &b_id, true)) 9680 return false; 9681 9682 return netdev_phys_item_id_same(&a_id, &b_id); 9683 } 9684 EXPORT_SYMBOL(netdev_port_same_parent_id); 9685 9686 /** 9687 * dev_change_proto_down - set carrier according to proto_down. 9688 * 9689 * @dev: device 9690 * @proto_down: new value 9691 */ 9692 int dev_change_proto_down(struct net_device *dev, bool proto_down) 9693 { 9694 if (!dev->change_proto_down) 9695 return -EOPNOTSUPP; 9696 if (!netif_device_present(dev)) 9697 return -ENODEV; 9698 if (proto_down) 9699 netif_carrier_off(dev); 9700 else 9701 netif_carrier_on(dev); 9702 WRITE_ONCE(dev->proto_down, proto_down); 9703 return 0; 9704 } 9705 9706 /** 9707 * dev_change_proto_down_reason - proto down reason 9708 * 9709 * @dev: device 9710 * @mask: proto down mask 9711 * @value: proto down value 9712 */ 9713 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 9714 u32 value) 9715 { 9716 u32 proto_down_reason; 9717 int b; 9718 9719 if (!mask) { 9720 proto_down_reason = value; 9721 } else { 9722 proto_down_reason = dev->proto_down_reason; 9723 for_each_set_bit(b, &mask, 32) { 9724 if (value & (1 << b)) 9725 proto_down_reason |= BIT(b); 9726 else 9727 proto_down_reason &= ~BIT(b); 9728 } 9729 } 9730 WRITE_ONCE(dev->proto_down_reason, proto_down_reason); 9731 } 9732 9733 struct bpf_xdp_link { 9734 struct bpf_link link; 9735 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 9736 int flags; 9737 }; 9738 9739 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 9740 { 9741 if (flags & XDP_FLAGS_HW_MODE) 9742 return XDP_MODE_HW; 9743 if (flags & XDP_FLAGS_DRV_MODE) 9744 return XDP_MODE_DRV; 9745 if (flags & XDP_FLAGS_SKB_MODE) 9746 return XDP_MODE_SKB; 9747 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 9748 } 9749 9750 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 9751 { 9752 switch (mode) { 9753 case XDP_MODE_SKB: 9754 return generic_xdp_install; 9755 case XDP_MODE_DRV: 9756 case XDP_MODE_HW: 9757 return dev->netdev_ops->ndo_bpf; 9758 default: 9759 return NULL; 9760 } 9761 } 9762 9763 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9764 enum bpf_xdp_mode mode) 9765 { 9766 return dev->xdp_state[mode].link; 9767 } 9768 9769 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9770 enum bpf_xdp_mode mode) 9771 { 9772 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9773 9774 if (link) 9775 return link->link.prog; 9776 return dev->xdp_state[mode].prog; 9777 } 9778 9779 u8 dev_xdp_prog_count(struct net_device *dev) 9780 { 9781 u8 count = 0; 9782 int i; 9783 9784 for (i = 0; i < __MAX_XDP_MODE; i++) 9785 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9786 count++; 9787 return count; 9788 } 9789 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9790 9791 u8 dev_xdp_sb_prog_count(struct net_device *dev) 9792 { 9793 u8 count = 0; 9794 int i; 9795 9796 for (i = 0; i < __MAX_XDP_MODE; i++) 9797 if (dev->xdp_state[i].prog && 9798 !dev->xdp_state[i].prog->aux->xdp_has_frags) 9799 count++; 9800 return count; 9801 } 9802 9803 int dev_xdp_propagate(struct net_device *dev, struct netdev_bpf *bpf) 9804 { 9805 if (!dev->netdev_ops->ndo_bpf) 9806 return -EOPNOTSUPP; 9807 9808 if (dev->cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED && 9809 bpf->command == XDP_SETUP_PROG && 9810 bpf->prog && !bpf->prog->aux->xdp_has_frags) { 9811 NL_SET_ERR_MSG(bpf->extack, 9812 "unable to propagate XDP to device using tcp-data-split"); 9813 return -EBUSY; 9814 } 9815 9816 if (dev_get_min_mp_channel_count(dev)) { 9817 NL_SET_ERR_MSG(bpf->extack, "unable to propagate XDP to device using memory provider"); 9818 return -EBUSY; 9819 } 9820 9821 return dev->netdev_ops->ndo_bpf(dev, bpf); 9822 } 9823 EXPORT_SYMBOL_GPL(dev_xdp_propagate); 9824 9825 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9826 { 9827 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9828 9829 return prog ? prog->aux->id : 0; 9830 } 9831 9832 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9833 struct bpf_xdp_link *link) 9834 { 9835 dev->xdp_state[mode].link = link; 9836 dev->xdp_state[mode].prog = NULL; 9837 } 9838 9839 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9840 struct bpf_prog *prog) 9841 { 9842 dev->xdp_state[mode].link = NULL; 9843 dev->xdp_state[mode].prog = prog; 9844 } 9845 9846 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9847 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9848 u32 flags, struct bpf_prog *prog) 9849 { 9850 struct netdev_bpf xdp; 9851 int err; 9852 9853 if (dev->cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED && 9854 prog && !prog->aux->xdp_has_frags) { 9855 NL_SET_ERR_MSG(extack, "unable to install XDP to device using tcp-data-split"); 9856 return -EBUSY; 9857 } 9858 9859 if (dev_get_min_mp_channel_count(dev)) { 9860 NL_SET_ERR_MSG(extack, "unable to install XDP to device using memory provider"); 9861 return -EBUSY; 9862 } 9863 9864 memset(&xdp, 0, sizeof(xdp)); 9865 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9866 xdp.extack = extack; 9867 xdp.flags = flags; 9868 xdp.prog = prog; 9869 9870 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9871 * "moved" into driver), so they don't increment it on their own, but 9872 * they do decrement refcnt when program is detached or replaced. 9873 * Given net_device also owns link/prog, we need to bump refcnt here 9874 * to prevent drivers from underflowing it. 9875 */ 9876 if (prog) 9877 bpf_prog_inc(prog); 9878 err = bpf_op(dev, &xdp); 9879 if (err) { 9880 if (prog) 9881 bpf_prog_put(prog); 9882 return err; 9883 } 9884 9885 if (mode != XDP_MODE_HW) 9886 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9887 9888 return 0; 9889 } 9890 9891 static void dev_xdp_uninstall(struct net_device *dev) 9892 { 9893 struct bpf_xdp_link *link; 9894 struct bpf_prog *prog; 9895 enum bpf_xdp_mode mode; 9896 bpf_op_t bpf_op; 9897 9898 ASSERT_RTNL(); 9899 9900 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9901 prog = dev_xdp_prog(dev, mode); 9902 if (!prog) 9903 continue; 9904 9905 bpf_op = dev_xdp_bpf_op(dev, mode); 9906 if (!bpf_op) 9907 continue; 9908 9909 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9910 9911 /* auto-detach link from net device */ 9912 link = dev_xdp_link(dev, mode); 9913 if (link) 9914 link->dev = NULL; 9915 else 9916 bpf_prog_put(prog); 9917 9918 dev_xdp_set_link(dev, mode, NULL); 9919 } 9920 } 9921 9922 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9923 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9924 struct bpf_prog *old_prog, u32 flags) 9925 { 9926 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9927 struct bpf_prog *cur_prog; 9928 struct net_device *upper; 9929 struct list_head *iter; 9930 enum bpf_xdp_mode mode; 9931 bpf_op_t bpf_op; 9932 int err; 9933 9934 ASSERT_RTNL(); 9935 9936 /* either link or prog attachment, never both */ 9937 if (link && (new_prog || old_prog)) 9938 return -EINVAL; 9939 /* link supports only XDP mode flags */ 9940 if (link && (flags & ~XDP_FLAGS_MODES)) { 9941 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9942 return -EINVAL; 9943 } 9944 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9945 if (num_modes > 1) { 9946 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9947 return -EINVAL; 9948 } 9949 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9950 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9951 NL_SET_ERR_MSG(extack, 9952 "More than one program loaded, unset mode is ambiguous"); 9953 return -EINVAL; 9954 } 9955 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9956 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9957 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9958 return -EINVAL; 9959 } 9960 9961 mode = dev_xdp_mode(dev, flags); 9962 /* can't replace attached link */ 9963 if (dev_xdp_link(dev, mode)) { 9964 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9965 return -EBUSY; 9966 } 9967 9968 /* don't allow if an upper device already has a program */ 9969 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9970 if (dev_xdp_prog_count(upper) > 0) { 9971 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9972 return -EEXIST; 9973 } 9974 } 9975 9976 cur_prog = dev_xdp_prog(dev, mode); 9977 /* can't replace attached prog with link */ 9978 if (link && cur_prog) { 9979 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9980 return -EBUSY; 9981 } 9982 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9983 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9984 return -EEXIST; 9985 } 9986 9987 /* put effective new program into new_prog */ 9988 if (link) 9989 new_prog = link->link.prog; 9990 9991 if (new_prog) { 9992 bool offload = mode == XDP_MODE_HW; 9993 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9994 ? XDP_MODE_DRV : XDP_MODE_SKB; 9995 9996 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9997 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9998 return -EBUSY; 9999 } 10000 if (!offload && dev_xdp_prog(dev, other_mode)) { 10001 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 10002 return -EEXIST; 10003 } 10004 if (!offload && bpf_prog_is_offloaded(new_prog->aux)) { 10005 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported"); 10006 return -EINVAL; 10007 } 10008 if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) { 10009 NL_SET_ERR_MSG(extack, "Program bound to different device"); 10010 return -EINVAL; 10011 } 10012 if (bpf_prog_is_dev_bound(new_prog->aux) && mode == XDP_MODE_SKB) { 10013 NL_SET_ERR_MSG(extack, "Can't attach device-bound programs in generic mode"); 10014 return -EINVAL; 10015 } 10016 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 10017 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 10018 return -EINVAL; 10019 } 10020 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 10021 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 10022 return -EINVAL; 10023 } 10024 } 10025 10026 /* don't call drivers if the effective program didn't change */ 10027 if (new_prog != cur_prog) { 10028 bpf_op = dev_xdp_bpf_op(dev, mode); 10029 if (!bpf_op) { 10030 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 10031 return -EOPNOTSUPP; 10032 } 10033 10034 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 10035 if (err) 10036 return err; 10037 } 10038 10039 if (link) 10040 dev_xdp_set_link(dev, mode, link); 10041 else 10042 dev_xdp_set_prog(dev, mode, new_prog); 10043 if (cur_prog) 10044 bpf_prog_put(cur_prog); 10045 10046 return 0; 10047 } 10048 10049 static int dev_xdp_attach_link(struct net_device *dev, 10050 struct netlink_ext_ack *extack, 10051 struct bpf_xdp_link *link) 10052 { 10053 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 10054 } 10055 10056 static int dev_xdp_detach_link(struct net_device *dev, 10057 struct netlink_ext_ack *extack, 10058 struct bpf_xdp_link *link) 10059 { 10060 enum bpf_xdp_mode mode; 10061 bpf_op_t bpf_op; 10062 10063 ASSERT_RTNL(); 10064 10065 mode = dev_xdp_mode(dev, link->flags); 10066 if (dev_xdp_link(dev, mode) != link) 10067 return -EINVAL; 10068 10069 bpf_op = dev_xdp_bpf_op(dev, mode); 10070 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 10071 dev_xdp_set_link(dev, mode, NULL); 10072 return 0; 10073 } 10074 10075 static void bpf_xdp_link_release(struct bpf_link *link) 10076 { 10077 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10078 10079 rtnl_lock(); 10080 10081 /* if racing with net_device's tear down, xdp_link->dev might be 10082 * already NULL, in which case link was already auto-detached 10083 */ 10084 if (xdp_link->dev) { 10085 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 10086 xdp_link->dev = NULL; 10087 } 10088 10089 rtnl_unlock(); 10090 } 10091 10092 static int bpf_xdp_link_detach(struct bpf_link *link) 10093 { 10094 bpf_xdp_link_release(link); 10095 return 0; 10096 } 10097 10098 static void bpf_xdp_link_dealloc(struct bpf_link *link) 10099 { 10100 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10101 10102 kfree(xdp_link); 10103 } 10104 10105 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 10106 struct seq_file *seq) 10107 { 10108 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10109 u32 ifindex = 0; 10110 10111 rtnl_lock(); 10112 if (xdp_link->dev) 10113 ifindex = xdp_link->dev->ifindex; 10114 rtnl_unlock(); 10115 10116 seq_printf(seq, "ifindex:\t%u\n", ifindex); 10117 } 10118 10119 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 10120 struct bpf_link_info *info) 10121 { 10122 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10123 u32 ifindex = 0; 10124 10125 rtnl_lock(); 10126 if (xdp_link->dev) 10127 ifindex = xdp_link->dev->ifindex; 10128 rtnl_unlock(); 10129 10130 info->xdp.ifindex = ifindex; 10131 return 0; 10132 } 10133 10134 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 10135 struct bpf_prog *old_prog) 10136 { 10137 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10138 enum bpf_xdp_mode mode; 10139 bpf_op_t bpf_op; 10140 int err = 0; 10141 10142 rtnl_lock(); 10143 10144 /* link might have been auto-released already, so fail */ 10145 if (!xdp_link->dev) { 10146 err = -ENOLINK; 10147 goto out_unlock; 10148 } 10149 10150 if (old_prog && link->prog != old_prog) { 10151 err = -EPERM; 10152 goto out_unlock; 10153 } 10154 old_prog = link->prog; 10155 if (old_prog->type != new_prog->type || 10156 old_prog->expected_attach_type != new_prog->expected_attach_type) { 10157 err = -EINVAL; 10158 goto out_unlock; 10159 } 10160 10161 if (old_prog == new_prog) { 10162 /* no-op, don't disturb drivers */ 10163 bpf_prog_put(new_prog); 10164 goto out_unlock; 10165 } 10166 10167 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 10168 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 10169 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 10170 xdp_link->flags, new_prog); 10171 if (err) 10172 goto out_unlock; 10173 10174 old_prog = xchg(&link->prog, new_prog); 10175 bpf_prog_put(old_prog); 10176 10177 out_unlock: 10178 rtnl_unlock(); 10179 return err; 10180 } 10181 10182 static const struct bpf_link_ops bpf_xdp_link_lops = { 10183 .release = bpf_xdp_link_release, 10184 .dealloc = bpf_xdp_link_dealloc, 10185 .detach = bpf_xdp_link_detach, 10186 .show_fdinfo = bpf_xdp_link_show_fdinfo, 10187 .fill_link_info = bpf_xdp_link_fill_link_info, 10188 .update_prog = bpf_xdp_link_update, 10189 }; 10190 10191 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 10192 { 10193 struct net *net = current->nsproxy->net_ns; 10194 struct bpf_link_primer link_primer; 10195 struct netlink_ext_ack extack = {}; 10196 struct bpf_xdp_link *link; 10197 struct net_device *dev; 10198 int err, fd; 10199 10200 rtnl_lock(); 10201 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 10202 if (!dev) { 10203 rtnl_unlock(); 10204 return -EINVAL; 10205 } 10206 10207 link = kzalloc(sizeof(*link), GFP_USER); 10208 if (!link) { 10209 err = -ENOMEM; 10210 goto unlock; 10211 } 10212 10213 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 10214 link->dev = dev; 10215 link->flags = attr->link_create.flags; 10216 10217 err = bpf_link_prime(&link->link, &link_primer); 10218 if (err) { 10219 kfree(link); 10220 goto unlock; 10221 } 10222 10223 err = dev_xdp_attach_link(dev, &extack, link); 10224 rtnl_unlock(); 10225 10226 if (err) { 10227 link->dev = NULL; 10228 bpf_link_cleanup(&link_primer); 10229 trace_bpf_xdp_link_attach_failed(extack._msg); 10230 goto out_put_dev; 10231 } 10232 10233 fd = bpf_link_settle(&link_primer); 10234 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 10235 dev_put(dev); 10236 return fd; 10237 10238 unlock: 10239 rtnl_unlock(); 10240 10241 out_put_dev: 10242 dev_put(dev); 10243 return err; 10244 } 10245 10246 /** 10247 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 10248 * @dev: device 10249 * @extack: netlink extended ack 10250 * @fd: new program fd or negative value to clear 10251 * @expected_fd: old program fd that userspace expects to replace or clear 10252 * @flags: xdp-related flags 10253 * 10254 * Set or clear a bpf program for a device 10255 */ 10256 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 10257 int fd, int expected_fd, u32 flags) 10258 { 10259 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 10260 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 10261 int err; 10262 10263 ASSERT_RTNL(); 10264 10265 if (fd >= 0) { 10266 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 10267 mode != XDP_MODE_SKB); 10268 if (IS_ERR(new_prog)) 10269 return PTR_ERR(new_prog); 10270 } 10271 10272 if (expected_fd >= 0) { 10273 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 10274 mode != XDP_MODE_SKB); 10275 if (IS_ERR(old_prog)) { 10276 err = PTR_ERR(old_prog); 10277 old_prog = NULL; 10278 goto err_out; 10279 } 10280 } 10281 10282 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 10283 10284 err_out: 10285 if (err && new_prog) 10286 bpf_prog_put(new_prog); 10287 if (old_prog) 10288 bpf_prog_put(old_prog); 10289 return err; 10290 } 10291 10292 u32 dev_get_min_mp_channel_count(const struct net_device *dev) 10293 { 10294 int i; 10295 10296 ASSERT_RTNL(); 10297 10298 for (i = dev->real_num_rx_queues - 1; i >= 0; i--) 10299 if (dev->_rx[i].mp_params.mp_priv) 10300 /* The channel count is the idx plus 1. */ 10301 return i + 1; 10302 10303 return 0; 10304 } 10305 10306 /** 10307 * dev_index_reserve() - allocate an ifindex in a namespace 10308 * @net: the applicable net namespace 10309 * @ifindex: requested ifindex, pass %0 to get one allocated 10310 * 10311 * Allocate a ifindex for a new device. Caller must either use the ifindex 10312 * to store the device (via list_netdevice()) or call dev_index_release() 10313 * to give the index up. 10314 * 10315 * Return: a suitable unique value for a new device interface number or -errno. 10316 */ 10317 static int dev_index_reserve(struct net *net, u32 ifindex) 10318 { 10319 int err; 10320 10321 if (ifindex > INT_MAX) { 10322 DEBUG_NET_WARN_ON_ONCE(1); 10323 return -EINVAL; 10324 } 10325 10326 if (!ifindex) 10327 err = xa_alloc_cyclic(&net->dev_by_index, &ifindex, NULL, 10328 xa_limit_31b, &net->ifindex, GFP_KERNEL); 10329 else 10330 err = xa_insert(&net->dev_by_index, ifindex, NULL, GFP_KERNEL); 10331 if (err < 0) 10332 return err; 10333 10334 return ifindex; 10335 } 10336 10337 static void dev_index_release(struct net *net, int ifindex) 10338 { 10339 /* Expect only unused indexes, unlist_netdevice() removes the used */ 10340 WARN_ON(xa_erase(&net->dev_by_index, ifindex)); 10341 } 10342 10343 static bool from_cleanup_net(void) 10344 { 10345 #ifdef CONFIG_NET_NS 10346 return current == cleanup_net_task; 10347 #else 10348 return false; 10349 #endif 10350 } 10351 10352 /* Delayed registration/unregisteration */ 10353 LIST_HEAD(net_todo_list); 10354 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 10355 atomic_t dev_unreg_count = ATOMIC_INIT(0); 10356 10357 static void net_set_todo(struct net_device *dev) 10358 { 10359 list_add_tail(&dev->todo_list, &net_todo_list); 10360 } 10361 10362 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 10363 struct net_device *upper, netdev_features_t features) 10364 { 10365 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 10366 netdev_features_t feature; 10367 int feature_bit; 10368 10369 for_each_netdev_feature(upper_disables, feature_bit) { 10370 feature = __NETIF_F_BIT(feature_bit); 10371 if (!(upper->wanted_features & feature) 10372 && (features & feature)) { 10373 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 10374 &feature, upper->name); 10375 features &= ~feature; 10376 } 10377 } 10378 10379 return features; 10380 } 10381 10382 static void netdev_sync_lower_features(struct net_device *upper, 10383 struct net_device *lower, netdev_features_t features) 10384 { 10385 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 10386 netdev_features_t feature; 10387 int feature_bit; 10388 10389 for_each_netdev_feature(upper_disables, feature_bit) { 10390 feature = __NETIF_F_BIT(feature_bit); 10391 if (!(features & feature) && (lower->features & feature)) { 10392 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 10393 &feature, lower->name); 10394 lower->wanted_features &= ~feature; 10395 __netdev_update_features(lower); 10396 10397 if (unlikely(lower->features & feature)) 10398 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 10399 &feature, lower->name); 10400 else 10401 netdev_features_change(lower); 10402 } 10403 } 10404 } 10405 10406 static bool netdev_has_ip_or_hw_csum(netdev_features_t features) 10407 { 10408 netdev_features_t ip_csum_mask = NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM; 10409 bool ip_csum = (features & ip_csum_mask) == ip_csum_mask; 10410 bool hw_csum = features & NETIF_F_HW_CSUM; 10411 10412 return ip_csum || hw_csum; 10413 } 10414 10415 static netdev_features_t netdev_fix_features(struct net_device *dev, 10416 netdev_features_t features) 10417 { 10418 /* Fix illegal checksum combinations */ 10419 if ((features & NETIF_F_HW_CSUM) && 10420 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 10421 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 10422 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 10423 } 10424 10425 /* TSO requires that SG is present as well. */ 10426 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 10427 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 10428 features &= ~NETIF_F_ALL_TSO; 10429 } 10430 10431 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 10432 !(features & NETIF_F_IP_CSUM)) { 10433 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 10434 features &= ~NETIF_F_TSO; 10435 features &= ~NETIF_F_TSO_ECN; 10436 } 10437 10438 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 10439 !(features & NETIF_F_IPV6_CSUM)) { 10440 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 10441 features &= ~NETIF_F_TSO6; 10442 } 10443 10444 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 10445 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 10446 features &= ~NETIF_F_TSO_MANGLEID; 10447 10448 /* TSO ECN requires that TSO is present as well. */ 10449 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 10450 features &= ~NETIF_F_TSO_ECN; 10451 10452 /* Software GSO depends on SG. */ 10453 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 10454 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 10455 features &= ~NETIF_F_GSO; 10456 } 10457 10458 /* GSO partial features require GSO partial be set */ 10459 if ((features & dev->gso_partial_features) && 10460 !(features & NETIF_F_GSO_PARTIAL)) { 10461 netdev_dbg(dev, 10462 "Dropping partially supported GSO features since no GSO partial.\n"); 10463 features &= ~dev->gso_partial_features; 10464 } 10465 10466 if (!(features & NETIF_F_RXCSUM)) { 10467 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 10468 * successfully merged by hardware must also have the 10469 * checksum verified by hardware. If the user does not 10470 * want to enable RXCSUM, logically, we should disable GRO_HW. 10471 */ 10472 if (features & NETIF_F_GRO_HW) { 10473 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 10474 features &= ~NETIF_F_GRO_HW; 10475 } 10476 } 10477 10478 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 10479 if (features & NETIF_F_RXFCS) { 10480 if (features & NETIF_F_LRO) { 10481 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 10482 features &= ~NETIF_F_LRO; 10483 } 10484 10485 if (features & NETIF_F_GRO_HW) { 10486 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 10487 features &= ~NETIF_F_GRO_HW; 10488 } 10489 } 10490 10491 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 10492 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 10493 features &= ~NETIF_F_LRO; 10494 } 10495 10496 if ((features & NETIF_F_HW_TLS_TX) && !netdev_has_ip_or_hw_csum(features)) { 10497 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 10498 features &= ~NETIF_F_HW_TLS_TX; 10499 } 10500 10501 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 10502 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 10503 features &= ~NETIF_F_HW_TLS_RX; 10504 } 10505 10506 if ((features & NETIF_F_GSO_UDP_L4) && !netdev_has_ip_or_hw_csum(features)) { 10507 netdev_dbg(dev, "Dropping USO feature since no CSUM feature.\n"); 10508 features &= ~NETIF_F_GSO_UDP_L4; 10509 } 10510 10511 return features; 10512 } 10513 10514 int __netdev_update_features(struct net_device *dev) 10515 { 10516 struct net_device *upper, *lower; 10517 netdev_features_t features; 10518 struct list_head *iter; 10519 int err = -1; 10520 10521 ASSERT_RTNL(); 10522 10523 features = netdev_get_wanted_features(dev); 10524 10525 if (dev->netdev_ops->ndo_fix_features) 10526 features = dev->netdev_ops->ndo_fix_features(dev, features); 10527 10528 /* driver might be less strict about feature dependencies */ 10529 features = netdev_fix_features(dev, features); 10530 10531 /* some features can't be enabled if they're off on an upper device */ 10532 netdev_for_each_upper_dev_rcu(dev, upper, iter) 10533 features = netdev_sync_upper_features(dev, upper, features); 10534 10535 if (dev->features == features) 10536 goto sync_lower; 10537 10538 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 10539 &dev->features, &features); 10540 10541 if (dev->netdev_ops->ndo_set_features) 10542 err = dev->netdev_ops->ndo_set_features(dev, features); 10543 else 10544 err = 0; 10545 10546 if (unlikely(err < 0)) { 10547 netdev_err(dev, 10548 "set_features() failed (%d); wanted %pNF, left %pNF\n", 10549 err, &features, &dev->features); 10550 /* return non-0 since some features might have changed and 10551 * it's better to fire a spurious notification than miss it 10552 */ 10553 return -1; 10554 } 10555 10556 sync_lower: 10557 /* some features must be disabled on lower devices when disabled 10558 * on an upper device (think: bonding master or bridge) 10559 */ 10560 netdev_for_each_lower_dev(dev, lower, iter) 10561 netdev_sync_lower_features(dev, lower, features); 10562 10563 if (!err) { 10564 netdev_features_t diff = features ^ dev->features; 10565 10566 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 10567 /* udp_tunnel_{get,drop}_rx_info both need 10568 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 10569 * device, or they won't do anything. 10570 * Thus we need to update dev->features 10571 * *before* calling udp_tunnel_get_rx_info, 10572 * but *after* calling udp_tunnel_drop_rx_info. 10573 */ 10574 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 10575 dev->features = features; 10576 udp_tunnel_get_rx_info(dev); 10577 } else { 10578 udp_tunnel_drop_rx_info(dev); 10579 } 10580 } 10581 10582 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 10583 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 10584 dev->features = features; 10585 err |= vlan_get_rx_ctag_filter_info(dev); 10586 } else { 10587 vlan_drop_rx_ctag_filter_info(dev); 10588 } 10589 } 10590 10591 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 10592 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 10593 dev->features = features; 10594 err |= vlan_get_rx_stag_filter_info(dev); 10595 } else { 10596 vlan_drop_rx_stag_filter_info(dev); 10597 } 10598 } 10599 10600 dev->features = features; 10601 } 10602 10603 return err < 0 ? 0 : 1; 10604 } 10605 10606 /** 10607 * netdev_update_features - recalculate device features 10608 * @dev: the device to check 10609 * 10610 * Recalculate dev->features set and send notifications if it 10611 * has changed. Should be called after driver or hardware dependent 10612 * conditions might have changed that influence the features. 10613 */ 10614 void netdev_update_features(struct net_device *dev) 10615 { 10616 if (__netdev_update_features(dev)) 10617 netdev_features_change(dev); 10618 } 10619 EXPORT_SYMBOL(netdev_update_features); 10620 10621 /** 10622 * netdev_change_features - recalculate device features 10623 * @dev: the device to check 10624 * 10625 * Recalculate dev->features set and send notifications even 10626 * if they have not changed. Should be called instead of 10627 * netdev_update_features() if also dev->vlan_features might 10628 * have changed to allow the changes to be propagated to stacked 10629 * VLAN devices. 10630 */ 10631 void netdev_change_features(struct net_device *dev) 10632 { 10633 __netdev_update_features(dev); 10634 netdev_features_change(dev); 10635 } 10636 EXPORT_SYMBOL(netdev_change_features); 10637 10638 /** 10639 * netif_stacked_transfer_operstate - transfer operstate 10640 * @rootdev: the root or lower level device to transfer state from 10641 * @dev: the device to transfer operstate to 10642 * 10643 * Transfer operational state from root to device. This is normally 10644 * called when a stacking relationship exists between the root 10645 * device and the device(a leaf device). 10646 */ 10647 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 10648 struct net_device *dev) 10649 { 10650 if (rootdev->operstate == IF_OPER_DORMANT) 10651 netif_dormant_on(dev); 10652 else 10653 netif_dormant_off(dev); 10654 10655 if (rootdev->operstate == IF_OPER_TESTING) 10656 netif_testing_on(dev); 10657 else 10658 netif_testing_off(dev); 10659 10660 if (netif_carrier_ok(rootdev)) 10661 netif_carrier_on(dev); 10662 else 10663 netif_carrier_off(dev); 10664 } 10665 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 10666 10667 static int netif_alloc_rx_queues(struct net_device *dev) 10668 { 10669 unsigned int i, count = dev->num_rx_queues; 10670 struct netdev_rx_queue *rx; 10671 size_t sz = count * sizeof(*rx); 10672 int err = 0; 10673 10674 BUG_ON(count < 1); 10675 10676 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10677 if (!rx) 10678 return -ENOMEM; 10679 10680 dev->_rx = rx; 10681 10682 for (i = 0; i < count; i++) { 10683 rx[i].dev = dev; 10684 10685 /* XDP RX-queue setup */ 10686 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 10687 if (err < 0) 10688 goto err_rxq_info; 10689 } 10690 return 0; 10691 10692 err_rxq_info: 10693 /* Rollback successful reg's and free other resources */ 10694 while (i--) 10695 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 10696 kvfree(dev->_rx); 10697 dev->_rx = NULL; 10698 return err; 10699 } 10700 10701 static void netif_free_rx_queues(struct net_device *dev) 10702 { 10703 unsigned int i, count = dev->num_rx_queues; 10704 10705 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 10706 if (!dev->_rx) 10707 return; 10708 10709 for (i = 0; i < count; i++) 10710 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 10711 10712 kvfree(dev->_rx); 10713 } 10714 10715 static void netdev_init_one_queue(struct net_device *dev, 10716 struct netdev_queue *queue, void *_unused) 10717 { 10718 /* Initialize queue lock */ 10719 spin_lock_init(&queue->_xmit_lock); 10720 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 10721 queue->xmit_lock_owner = -1; 10722 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 10723 queue->dev = dev; 10724 #ifdef CONFIG_BQL 10725 dql_init(&queue->dql, HZ); 10726 #endif 10727 } 10728 10729 static void netif_free_tx_queues(struct net_device *dev) 10730 { 10731 kvfree(dev->_tx); 10732 } 10733 10734 static int netif_alloc_netdev_queues(struct net_device *dev) 10735 { 10736 unsigned int count = dev->num_tx_queues; 10737 struct netdev_queue *tx; 10738 size_t sz = count * sizeof(*tx); 10739 10740 if (count < 1 || count > 0xffff) 10741 return -EINVAL; 10742 10743 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10744 if (!tx) 10745 return -ENOMEM; 10746 10747 dev->_tx = tx; 10748 10749 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 10750 spin_lock_init(&dev->tx_global_lock); 10751 10752 return 0; 10753 } 10754 10755 void netif_tx_stop_all_queues(struct net_device *dev) 10756 { 10757 unsigned int i; 10758 10759 for (i = 0; i < dev->num_tx_queues; i++) { 10760 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 10761 10762 netif_tx_stop_queue(txq); 10763 } 10764 } 10765 EXPORT_SYMBOL(netif_tx_stop_all_queues); 10766 10767 static int netdev_do_alloc_pcpu_stats(struct net_device *dev) 10768 { 10769 void __percpu *v; 10770 10771 /* Drivers implementing ndo_get_peer_dev must support tstat 10772 * accounting, so that skb_do_redirect() can bump the dev's 10773 * RX stats upon network namespace switch. 10774 */ 10775 if (dev->netdev_ops->ndo_get_peer_dev && 10776 dev->pcpu_stat_type != NETDEV_PCPU_STAT_TSTATS) 10777 return -EOPNOTSUPP; 10778 10779 switch (dev->pcpu_stat_type) { 10780 case NETDEV_PCPU_STAT_NONE: 10781 return 0; 10782 case NETDEV_PCPU_STAT_LSTATS: 10783 v = dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); 10784 break; 10785 case NETDEV_PCPU_STAT_TSTATS: 10786 v = dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 10787 break; 10788 case NETDEV_PCPU_STAT_DSTATS: 10789 v = dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats); 10790 break; 10791 default: 10792 return -EINVAL; 10793 } 10794 10795 return v ? 0 : -ENOMEM; 10796 } 10797 10798 static void netdev_do_free_pcpu_stats(struct net_device *dev) 10799 { 10800 switch (dev->pcpu_stat_type) { 10801 case NETDEV_PCPU_STAT_NONE: 10802 return; 10803 case NETDEV_PCPU_STAT_LSTATS: 10804 free_percpu(dev->lstats); 10805 break; 10806 case NETDEV_PCPU_STAT_TSTATS: 10807 free_percpu(dev->tstats); 10808 break; 10809 case NETDEV_PCPU_STAT_DSTATS: 10810 free_percpu(dev->dstats); 10811 break; 10812 } 10813 } 10814 10815 static void netdev_free_phy_link_topology(struct net_device *dev) 10816 { 10817 struct phy_link_topology *topo = dev->link_topo; 10818 10819 if (IS_ENABLED(CONFIG_PHYLIB) && topo) { 10820 xa_destroy(&topo->phys); 10821 kfree(topo); 10822 dev->link_topo = NULL; 10823 } 10824 } 10825 10826 /** 10827 * register_netdevice() - register a network device 10828 * @dev: device to register 10829 * 10830 * Take a prepared network device structure and make it externally accessible. 10831 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 10832 * Callers must hold the rtnl lock - you may want register_netdev() 10833 * instead of this. 10834 */ 10835 int register_netdevice(struct net_device *dev) 10836 { 10837 int ret; 10838 struct net *net = dev_net(dev); 10839 10840 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 10841 NETDEV_FEATURE_COUNT); 10842 BUG_ON(dev_boot_phase); 10843 ASSERT_RTNL(); 10844 10845 might_sleep(); 10846 10847 /* When net_device's are persistent, this will be fatal. */ 10848 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 10849 BUG_ON(!net); 10850 10851 ret = ethtool_check_ops(dev->ethtool_ops); 10852 if (ret) 10853 return ret; 10854 10855 /* rss ctx ID 0 is reserved for the default context, start from 1 */ 10856 xa_init_flags(&dev->ethtool->rss_ctx, XA_FLAGS_ALLOC1); 10857 mutex_init(&dev->ethtool->rss_lock); 10858 10859 spin_lock_init(&dev->addr_list_lock); 10860 netdev_set_addr_lockdep_class(dev); 10861 10862 ret = dev_get_valid_name(net, dev, dev->name); 10863 if (ret < 0) 10864 goto out; 10865 10866 ret = -ENOMEM; 10867 dev->name_node = netdev_name_node_head_alloc(dev); 10868 if (!dev->name_node) 10869 goto out; 10870 10871 /* Init, if this function is available */ 10872 if (dev->netdev_ops->ndo_init) { 10873 ret = dev->netdev_ops->ndo_init(dev); 10874 if (ret) { 10875 if (ret > 0) 10876 ret = -EIO; 10877 goto err_free_name; 10878 } 10879 } 10880 10881 if (((dev->hw_features | dev->features) & 10882 NETIF_F_HW_VLAN_CTAG_FILTER) && 10883 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 10884 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 10885 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 10886 ret = -EINVAL; 10887 goto err_uninit; 10888 } 10889 10890 ret = netdev_do_alloc_pcpu_stats(dev); 10891 if (ret) 10892 goto err_uninit; 10893 10894 ret = dev_index_reserve(net, dev->ifindex); 10895 if (ret < 0) 10896 goto err_free_pcpu; 10897 dev->ifindex = ret; 10898 10899 /* Transfer changeable features to wanted_features and enable 10900 * software offloads (GSO and GRO). 10901 */ 10902 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 10903 dev->features |= NETIF_F_SOFT_FEATURES; 10904 10905 if (dev->udp_tunnel_nic_info) { 10906 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10907 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10908 } 10909 10910 dev->wanted_features = dev->features & dev->hw_features; 10911 10912 if (!(dev->flags & IFF_LOOPBACK)) 10913 dev->hw_features |= NETIF_F_NOCACHE_COPY; 10914 10915 /* If IPv4 TCP segmentation offload is supported we should also 10916 * allow the device to enable segmenting the frame with the option 10917 * of ignoring a static IP ID value. This doesn't enable the 10918 * feature itself but allows the user to enable it later. 10919 */ 10920 if (dev->hw_features & NETIF_F_TSO) 10921 dev->hw_features |= NETIF_F_TSO_MANGLEID; 10922 if (dev->vlan_features & NETIF_F_TSO) 10923 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10924 if (dev->mpls_features & NETIF_F_TSO) 10925 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10926 if (dev->hw_enc_features & NETIF_F_TSO) 10927 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10928 10929 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10930 */ 10931 dev->vlan_features |= NETIF_F_HIGHDMA; 10932 10933 /* Make NETIF_F_SG inheritable to tunnel devices. 10934 */ 10935 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10936 10937 /* Make NETIF_F_SG inheritable to MPLS. 10938 */ 10939 dev->mpls_features |= NETIF_F_SG; 10940 10941 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10942 ret = notifier_to_errno(ret); 10943 if (ret) 10944 goto err_ifindex_release; 10945 10946 ret = netdev_register_kobject(dev); 10947 10948 netdev_lock(dev); 10949 WRITE_ONCE(dev->reg_state, ret ? NETREG_UNREGISTERED : NETREG_REGISTERED); 10950 netdev_unlock(dev); 10951 10952 if (ret) 10953 goto err_uninit_notify; 10954 10955 __netdev_update_features(dev); 10956 10957 /* 10958 * Default initial state at registry is that the 10959 * device is present. 10960 */ 10961 10962 set_bit(__LINK_STATE_PRESENT, &dev->state); 10963 10964 linkwatch_init_dev(dev); 10965 10966 dev_init_scheduler(dev); 10967 10968 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10969 list_netdevice(dev); 10970 10971 add_device_randomness(dev->dev_addr, dev->addr_len); 10972 10973 /* If the device has permanent device address, driver should 10974 * set dev_addr and also addr_assign_type should be set to 10975 * NET_ADDR_PERM (default value). 10976 */ 10977 if (dev->addr_assign_type == NET_ADDR_PERM) 10978 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10979 10980 /* Notify protocols, that a new device appeared. */ 10981 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10982 ret = notifier_to_errno(ret); 10983 if (ret) { 10984 /* Expect explicit free_netdev() on failure */ 10985 dev->needs_free_netdev = false; 10986 unregister_netdevice_queue(dev, NULL); 10987 goto out; 10988 } 10989 /* 10990 * Prevent userspace races by waiting until the network 10991 * device is fully setup before sending notifications. 10992 */ 10993 if (!dev->rtnl_link_ops || 10994 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10995 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 10996 10997 out: 10998 return ret; 10999 11000 err_uninit_notify: 11001 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 11002 err_ifindex_release: 11003 dev_index_release(net, dev->ifindex); 11004 err_free_pcpu: 11005 netdev_do_free_pcpu_stats(dev); 11006 err_uninit: 11007 if (dev->netdev_ops->ndo_uninit) 11008 dev->netdev_ops->ndo_uninit(dev); 11009 if (dev->priv_destructor) 11010 dev->priv_destructor(dev); 11011 err_free_name: 11012 netdev_name_node_free(dev->name_node); 11013 goto out; 11014 } 11015 EXPORT_SYMBOL(register_netdevice); 11016 11017 /* Initialize the core of a dummy net device. 11018 * The setup steps dummy netdevs need which normal netdevs get by going 11019 * through register_netdevice(). 11020 */ 11021 static void init_dummy_netdev(struct net_device *dev) 11022 { 11023 /* make sure we BUG if trying to hit standard 11024 * register/unregister code path 11025 */ 11026 dev->reg_state = NETREG_DUMMY; 11027 11028 /* a dummy interface is started by default */ 11029 set_bit(__LINK_STATE_PRESENT, &dev->state); 11030 set_bit(__LINK_STATE_START, &dev->state); 11031 11032 /* Note : We dont allocate pcpu_refcnt for dummy devices, 11033 * because users of this 'device' dont need to change 11034 * its refcount. 11035 */ 11036 } 11037 11038 /** 11039 * register_netdev - register a network device 11040 * @dev: device to register 11041 * 11042 * Take a completed network device structure and add it to the kernel 11043 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 11044 * chain. 0 is returned on success. A negative errno code is returned 11045 * on a failure to set up the device, or if the name is a duplicate. 11046 * 11047 * This is a wrapper around register_netdevice that takes the rtnl semaphore 11048 * and expands the device name if you passed a format string to 11049 * alloc_netdev. 11050 */ 11051 int register_netdev(struct net_device *dev) 11052 { 11053 struct net *net = dev_net(dev); 11054 int err; 11055 11056 if (rtnl_net_lock_killable(net)) 11057 return -EINTR; 11058 11059 err = register_netdevice(dev); 11060 11061 rtnl_net_unlock(net); 11062 11063 return err; 11064 } 11065 EXPORT_SYMBOL(register_netdev); 11066 11067 int netdev_refcnt_read(const struct net_device *dev) 11068 { 11069 #ifdef CONFIG_PCPU_DEV_REFCNT 11070 int i, refcnt = 0; 11071 11072 for_each_possible_cpu(i) 11073 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 11074 return refcnt; 11075 #else 11076 return refcount_read(&dev->dev_refcnt); 11077 #endif 11078 } 11079 EXPORT_SYMBOL(netdev_refcnt_read); 11080 11081 int netdev_unregister_timeout_secs __read_mostly = 10; 11082 11083 #define WAIT_REFS_MIN_MSECS 1 11084 #define WAIT_REFS_MAX_MSECS 250 11085 /** 11086 * netdev_wait_allrefs_any - wait until all references are gone. 11087 * @list: list of net_devices to wait on 11088 * 11089 * This is called when unregistering network devices. 11090 * 11091 * Any protocol or device that holds a reference should register 11092 * for netdevice notification, and cleanup and put back the 11093 * reference if they receive an UNREGISTER event. 11094 * We can get stuck here if buggy protocols don't correctly 11095 * call dev_put. 11096 */ 11097 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 11098 { 11099 unsigned long rebroadcast_time, warning_time; 11100 struct net_device *dev; 11101 int wait = 0; 11102 11103 rebroadcast_time = warning_time = jiffies; 11104 11105 list_for_each_entry(dev, list, todo_list) 11106 if (netdev_refcnt_read(dev) == 1) 11107 return dev; 11108 11109 while (true) { 11110 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 11111 rtnl_lock(); 11112 11113 /* Rebroadcast unregister notification */ 11114 list_for_each_entry(dev, list, todo_list) 11115 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11116 11117 __rtnl_unlock(); 11118 rcu_barrier(); 11119 rtnl_lock(); 11120 11121 list_for_each_entry(dev, list, todo_list) 11122 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 11123 &dev->state)) { 11124 /* We must not have linkwatch events 11125 * pending on unregister. If this 11126 * happens, we simply run the queue 11127 * unscheduled, resulting in a noop 11128 * for this device. 11129 */ 11130 linkwatch_run_queue(); 11131 break; 11132 } 11133 11134 __rtnl_unlock(); 11135 11136 rebroadcast_time = jiffies; 11137 } 11138 11139 rcu_barrier(); 11140 11141 if (!wait) { 11142 wait = WAIT_REFS_MIN_MSECS; 11143 } else { 11144 msleep(wait); 11145 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 11146 } 11147 11148 list_for_each_entry(dev, list, todo_list) 11149 if (netdev_refcnt_read(dev) == 1) 11150 return dev; 11151 11152 if (time_after(jiffies, warning_time + 11153 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 11154 list_for_each_entry(dev, list, todo_list) { 11155 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 11156 dev->name, netdev_refcnt_read(dev)); 11157 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 11158 } 11159 11160 warning_time = jiffies; 11161 } 11162 } 11163 } 11164 11165 /* The sequence is: 11166 * 11167 * rtnl_lock(); 11168 * ... 11169 * register_netdevice(x1); 11170 * register_netdevice(x2); 11171 * ... 11172 * unregister_netdevice(y1); 11173 * unregister_netdevice(y2); 11174 * ... 11175 * rtnl_unlock(); 11176 * free_netdev(y1); 11177 * free_netdev(y2); 11178 * 11179 * We are invoked by rtnl_unlock(). 11180 * This allows us to deal with problems: 11181 * 1) We can delete sysfs objects which invoke hotplug 11182 * without deadlocking with linkwatch via keventd. 11183 * 2) Since we run with the RTNL semaphore not held, we can sleep 11184 * safely in order to wait for the netdev refcnt to drop to zero. 11185 * 11186 * We must not return until all unregister events added during 11187 * the interval the lock was held have been completed. 11188 */ 11189 void netdev_run_todo(void) 11190 { 11191 struct net_device *dev, *tmp; 11192 struct list_head list; 11193 int cnt; 11194 #ifdef CONFIG_LOCKDEP 11195 struct list_head unlink_list; 11196 11197 list_replace_init(&net_unlink_list, &unlink_list); 11198 11199 while (!list_empty(&unlink_list)) { 11200 struct net_device *dev = list_first_entry(&unlink_list, 11201 struct net_device, 11202 unlink_list); 11203 list_del_init(&dev->unlink_list); 11204 dev->nested_level = dev->lower_level - 1; 11205 } 11206 #endif 11207 11208 /* Snapshot list, allow later requests */ 11209 list_replace_init(&net_todo_list, &list); 11210 11211 __rtnl_unlock(); 11212 11213 /* Wait for rcu callbacks to finish before next phase */ 11214 if (!list_empty(&list)) 11215 rcu_barrier(); 11216 11217 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 11218 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 11219 netdev_WARN(dev, "run_todo but not unregistering\n"); 11220 list_del(&dev->todo_list); 11221 continue; 11222 } 11223 11224 netdev_lock(dev); 11225 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERED); 11226 netdev_unlock(dev); 11227 linkwatch_sync_dev(dev); 11228 } 11229 11230 cnt = 0; 11231 while (!list_empty(&list)) { 11232 dev = netdev_wait_allrefs_any(&list); 11233 list_del(&dev->todo_list); 11234 11235 /* paranoia */ 11236 BUG_ON(netdev_refcnt_read(dev) != 1); 11237 BUG_ON(!list_empty(&dev->ptype_all)); 11238 BUG_ON(!list_empty(&dev->ptype_specific)); 11239 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 11240 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 11241 11242 netdev_do_free_pcpu_stats(dev); 11243 if (dev->priv_destructor) 11244 dev->priv_destructor(dev); 11245 if (dev->needs_free_netdev) 11246 free_netdev(dev); 11247 11248 cnt++; 11249 11250 /* Free network device */ 11251 kobject_put(&dev->dev.kobj); 11252 } 11253 if (cnt && atomic_sub_and_test(cnt, &dev_unreg_count)) 11254 wake_up(&netdev_unregistering_wq); 11255 } 11256 11257 /* Collate per-cpu network dstats statistics 11258 * 11259 * Read per-cpu network statistics from dev->dstats and populate the related 11260 * fields in @s. 11261 */ 11262 static void dev_fetch_dstats(struct rtnl_link_stats64 *s, 11263 const struct pcpu_dstats __percpu *dstats) 11264 { 11265 int cpu; 11266 11267 for_each_possible_cpu(cpu) { 11268 u64 rx_packets, rx_bytes, rx_drops; 11269 u64 tx_packets, tx_bytes, tx_drops; 11270 const struct pcpu_dstats *stats; 11271 unsigned int start; 11272 11273 stats = per_cpu_ptr(dstats, cpu); 11274 do { 11275 start = u64_stats_fetch_begin(&stats->syncp); 11276 rx_packets = u64_stats_read(&stats->rx_packets); 11277 rx_bytes = u64_stats_read(&stats->rx_bytes); 11278 rx_drops = u64_stats_read(&stats->rx_drops); 11279 tx_packets = u64_stats_read(&stats->tx_packets); 11280 tx_bytes = u64_stats_read(&stats->tx_bytes); 11281 tx_drops = u64_stats_read(&stats->tx_drops); 11282 } while (u64_stats_fetch_retry(&stats->syncp, start)); 11283 11284 s->rx_packets += rx_packets; 11285 s->rx_bytes += rx_bytes; 11286 s->rx_dropped += rx_drops; 11287 s->tx_packets += tx_packets; 11288 s->tx_bytes += tx_bytes; 11289 s->tx_dropped += tx_drops; 11290 } 11291 } 11292 11293 /* ndo_get_stats64 implementation for dtstats-based accounting. 11294 * 11295 * Populate @s from dev->stats and dev->dstats. This is used internally by the 11296 * core for NETDEV_PCPU_STAT_DSTAT-type stats collection. 11297 */ 11298 static void dev_get_dstats64(const struct net_device *dev, 11299 struct rtnl_link_stats64 *s) 11300 { 11301 netdev_stats_to_stats64(s, &dev->stats); 11302 dev_fetch_dstats(s, dev->dstats); 11303 } 11304 11305 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 11306 * all the same fields in the same order as net_device_stats, with only 11307 * the type differing, but rtnl_link_stats64 may have additional fields 11308 * at the end for newer counters. 11309 */ 11310 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 11311 const struct net_device_stats *netdev_stats) 11312 { 11313 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t); 11314 const atomic_long_t *src = (atomic_long_t *)netdev_stats; 11315 u64 *dst = (u64 *)stats64; 11316 11317 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 11318 for (i = 0; i < n; i++) 11319 dst[i] = (unsigned long)atomic_long_read(&src[i]); 11320 /* zero out counters that only exist in rtnl_link_stats64 */ 11321 memset((char *)stats64 + n * sizeof(u64), 0, 11322 sizeof(*stats64) - n * sizeof(u64)); 11323 } 11324 EXPORT_SYMBOL(netdev_stats_to_stats64); 11325 11326 static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc( 11327 struct net_device *dev) 11328 { 11329 struct net_device_core_stats __percpu *p; 11330 11331 p = alloc_percpu_gfp(struct net_device_core_stats, 11332 GFP_ATOMIC | __GFP_NOWARN); 11333 11334 if (p && cmpxchg(&dev->core_stats, NULL, p)) 11335 free_percpu(p); 11336 11337 /* This READ_ONCE() pairs with the cmpxchg() above */ 11338 return READ_ONCE(dev->core_stats); 11339 } 11340 11341 noinline void netdev_core_stats_inc(struct net_device *dev, u32 offset) 11342 { 11343 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 11344 struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); 11345 unsigned long __percpu *field; 11346 11347 if (unlikely(!p)) { 11348 p = netdev_core_stats_alloc(dev); 11349 if (!p) 11350 return; 11351 } 11352 11353 field = (unsigned long __percpu *)((void __percpu *)p + offset); 11354 this_cpu_inc(*field); 11355 } 11356 EXPORT_SYMBOL_GPL(netdev_core_stats_inc); 11357 11358 /** 11359 * dev_get_stats - get network device statistics 11360 * @dev: device to get statistics from 11361 * @storage: place to store stats 11362 * 11363 * Get network statistics from device. Return @storage. 11364 * The device driver may provide its own method by setting 11365 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 11366 * otherwise the internal statistics structure is used. 11367 */ 11368 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 11369 struct rtnl_link_stats64 *storage) 11370 { 11371 const struct net_device_ops *ops = dev->netdev_ops; 11372 const struct net_device_core_stats __percpu *p; 11373 11374 /* 11375 * IPv{4,6} and udp tunnels share common stat helpers and use 11376 * different stat type (NETDEV_PCPU_STAT_TSTATS vs 11377 * NETDEV_PCPU_STAT_DSTATS). Ensure the accounting is consistent. 11378 */ 11379 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, rx_bytes) != 11380 offsetof(struct pcpu_dstats, rx_bytes)); 11381 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, rx_packets) != 11382 offsetof(struct pcpu_dstats, rx_packets)); 11383 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, tx_bytes) != 11384 offsetof(struct pcpu_dstats, tx_bytes)); 11385 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, tx_packets) != 11386 offsetof(struct pcpu_dstats, tx_packets)); 11387 11388 if (ops->ndo_get_stats64) { 11389 memset(storage, 0, sizeof(*storage)); 11390 ops->ndo_get_stats64(dev, storage); 11391 } else if (ops->ndo_get_stats) { 11392 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 11393 } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) { 11394 dev_get_tstats64(dev, storage); 11395 } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) { 11396 dev_get_dstats64(dev, storage); 11397 } else { 11398 netdev_stats_to_stats64(storage, &dev->stats); 11399 } 11400 11401 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 11402 p = READ_ONCE(dev->core_stats); 11403 if (p) { 11404 const struct net_device_core_stats *core_stats; 11405 int i; 11406 11407 for_each_possible_cpu(i) { 11408 core_stats = per_cpu_ptr(p, i); 11409 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 11410 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 11411 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 11412 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 11413 } 11414 } 11415 return storage; 11416 } 11417 EXPORT_SYMBOL(dev_get_stats); 11418 11419 /** 11420 * dev_fetch_sw_netstats - get per-cpu network device statistics 11421 * @s: place to store stats 11422 * @netstats: per-cpu network stats to read from 11423 * 11424 * Read per-cpu network statistics and populate the related fields in @s. 11425 */ 11426 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 11427 const struct pcpu_sw_netstats __percpu *netstats) 11428 { 11429 int cpu; 11430 11431 for_each_possible_cpu(cpu) { 11432 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 11433 const struct pcpu_sw_netstats *stats; 11434 unsigned int start; 11435 11436 stats = per_cpu_ptr(netstats, cpu); 11437 do { 11438 start = u64_stats_fetch_begin(&stats->syncp); 11439 rx_packets = u64_stats_read(&stats->rx_packets); 11440 rx_bytes = u64_stats_read(&stats->rx_bytes); 11441 tx_packets = u64_stats_read(&stats->tx_packets); 11442 tx_bytes = u64_stats_read(&stats->tx_bytes); 11443 } while (u64_stats_fetch_retry(&stats->syncp, start)); 11444 11445 s->rx_packets += rx_packets; 11446 s->rx_bytes += rx_bytes; 11447 s->tx_packets += tx_packets; 11448 s->tx_bytes += tx_bytes; 11449 } 11450 } 11451 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 11452 11453 /** 11454 * dev_get_tstats64 - ndo_get_stats64 implementation 11455 * @dev: device to get statistics from 11456 * @s: place to store stats 11457 * 11458 * Populate @s from dev->stats and dev->tstats. Can be used as 11459 * ndo_get_stats64() callback. 11460 */ 11461 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 11462 { 11463 netdev_stats_to_stats64(s, &dev->stats); 11464 dev_fetch_sw_netstats(s, dev->tstats); 11465 } 11466 EXPORT_SYMBOL_GPL(dev_get_tstats64); 11467 11468 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 11469 { 11470 struct netdev_queue *queue = dev_ingress_queue(dev); 11471 11472 #ifdef CONFIG_NET_CLS_ACT 11473 if (queue) 11474 return queue; 11475 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 11476 if (!queue) 11477 return NULL; 11478 netdev_init_one_queue(dev, queue, NULL); 11479 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 11480 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc); 11481 rcu_assign_pointer(dev->ingress_queue, queue); 11482 #endif 11483 return queue; 11484 } 11485 11486 static const struct ethtool_ops default_ethtool_ops; 11487 11488 void netdev_set_default_ethtool_ops(struct net_device *dev, 11489 const struct ethtool_ops *ops) 11490 { 11491 if (dev->ethtool_ops == &default_ethtool_ops) 11492 dev->ethtool_ops = ops; 11493 } 11494 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 11495 11496 /** 11497 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default 11498 * @dev: netdev to enable the IRQ coalescing on 11499 * 11500 * Sets a conservative default for SW IRQ coalescing. Users can use 11501 * sysfs attributes to override the default values. 11502 */ 11503 void netdev_sw_irq_coalesce_default_on(struct net_device *dev) 11504 { 11505 WARN_ON(dev->reg_state == NETREG_REGISTERED); 11506 11507 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { 11508 netdev_set_gro_flush_timeout(dev, 20000); 11509 netdev_set_defer_hard_irqs(dev, 1); 11510 } 11511 } 11512 EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); 11513 11514 /** 11515 * alloc_netdev_mqs - allocate network device 11516 * @sizeof_priv: size of private data to allocate space for 11517 * @name: device name format string 11518 * @name_assign_type: origin of device name 11519 * @setup: callback to initialize device 11520 * @txqs: the number of TX subqueues to allocate 11521 * @rxqs: the number of RX subqueues to allocate 11522 * 11523 * Allocates a struct net_device with private data area for driver use 11524 * and performs basic initialization. Also allocates subqueue structs 11525 * for each queue on the device. 11526 */ 11527 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 11528 unsigned char name_assign_type, 11529 void (*setup)(struct net_device *), 11530 unsigned int txqs, unsigned int rxqs) 11531 { 11532 struct net_device *dev; 11533 size_t napi_config_sz; 11534 unsigned int maxqs; 11535 11536 BUG_ON(strlen(name) >= sizeof(dev->name)); 11537 11538 if (txqs < 1) { 11539 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 11540 return NULL; 11541 } 11542 11543 if (rxqs < 1) { 11544 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 11545 return NULL; 11546 } 11547 11548 maxqs = max(txqs, rxqs); 11549 11550 dev = kvzalloc(struct_size(dev, priv, sizeof_priv), 11551 GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 11552 if (!dev) 11553 return NULL; 11554 11555 dev->priv_len = sizeof_priv; 11556 11557 ref_tracker_dir_init(&dev->refcnt_tracker, 128, name); 11558 #ifdef CONFIG_PCPU_DEV_REFCNT 11559 dev->pcpu_refcnt = alloc_percpu(int); 11560 if (!dev->pcpu_refcnt) 11561 goto free_dev; 11562 __dev_hold(dev); 11563 #else 11564 refcount_set(&dev->dev_refcnt, 1); 11565 #endif 11566 11567 if (dev_addr_init(dev)) 11568 goto free_pcpu; 11569 11570 dev_mc_init(dev); 11571 dev_uc_init(dev); 11572 11573 dev_net_set(dev, &init_net); 11574 11575 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 11576 dev->xdp_zc_max_segs = 1; 11577 dev->gso_max_segs = GSO_MAX_SEGS; 11578 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 11579 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE; 11580 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE; 11581 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 11582 dev->tso_max_segs = TSO_MAX_SEGS; 11583 dev->upper_level = 1; 11584 dev->lower_level = 1; 11585 #ifdef CONFIG_LOCKDEP 11586 dev->nested_level = 0; 11587 INIT_LIST_HEAD(&dev->unlink_list); 11588 #endif 11589 11590 INIT_LIST_HEAD(&dev->napi_list); 11591 INIT_LIST_HEAD(&dev->unreg_list); 11592 INIT_LIST_HEAD(&dev->close_list); 11593 INIT_LIST_HEAD(&dev->link_watch_list); 11594 INIT_LIST_HEAD(&dev->adj_list.upper); 11595 INIT_LIST_HEAD(&dev->adj_list.lower); 11596 INIT_LIST_HEAD(&dev->ptype_all); 11597 INIT_LIST_HEAD(&dev->ptype_specific); 11598 INIT_LIST_HEAD(&dev->net_notifier_list); 11599 #ifdef CONFIG_NET_SCHED 11600 hash_init(dev->qdisc_hash); 11601 #endif 11602 11603 mutex_init(&dev->lock); 11604 11605 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 11606 setup(dev); 11607 11608 if (!dev->tx_queue_len) { 11609 dev->priv_flags |= IFF_NO_QUEUE; 11610 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 11611 } 11612 11613 dev->num_tx_queues = txqs; 11614 dev->real_num_tx_queues = txqs; 11615 if (netif_alloc_netdev_queues(dev)) 11616 goto free_all; 11617 11618 dev->num_rx_queues = rxqs; 11619 dev->real_num_rx_queues = rxqs; 11620 if (netif_alloc_rx_queues(dev)) 11621 goto free_all; 11622 dev->ethtool = kzalloc(sizeof(*dev->ethtool), GFP_KERNEL_ACCOUNT); 11623 if (!dev->ethtool) 11624 goto free_all; 11625 11626 dev->cfg = kzalloc(sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT); 11627 if (!dev->cfg) 11628 goto free_all; 11629 dev->cfg_pending = dev->cfg; 11630 11631 napi_config_sz = array_size(maxqs, sizeof(*dev->napi_config)); 11632 dev->napi_config = kvzalloc(napi_config_sz, GFP_KERNEL_ACCOUNT); 11633 if (!dev->napi_config) 11634 goto free_all; 11635 11636 strscpy(dev->name, name); 11637 dev->name_assign_type = name_assign_type; 11638 dev->group = INIT_NETDEV_GROUP; 11639 if (!dev->ethtool_ops) 11640 dev->ethtool_ops = &default_ethtool_ops; 11641 11642 nf_hook_netdev_init(dev); 11643 11644 return dev; 11645 11646 free_all: 11647 free_netdev(dev); 11648 return NULL; 11649 11650 free_pcpu: 11651 #ifdef CONFIG_PCPU_DEV_REFCNT 11652 free_percpu(dev->pcpu_refcnt); 11653 free_dev: 11654 #endif 11655 kvfree(dev); 11656 return NULL; 11657 } 11658 EXPORT_SYMBOL(alloc_netdev_mqs); 11659 11660 static void netdev_napi_exit(struct net_device *dev) 11661 { 11662 if (!list_empty(&dev->napi_list)) { 11663 struct napi_struct *p, *n; 11664 11665 netdev_lock(dev); 11666 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 11667 __netif_napi_del_locked(p); 11668 netdev_unlock(dev); 11669 11670 synchronize_net(); 11671 } 11672 11673 kvfree(dev->napi_config); 11674 } 11675 11676 /** 11677 * free_netdev - free network device 11678 * @dev: device 11679 * 11680 * This function does the last stage of destroying an allocated device 11681 * interface. The reference to the device object is released. If this 11682 * is the last reference then it will be freed.Must be called in process 11683 * context. 11684 */ 11685 void free_netdev(struct net_device *dev) 11686 { 11687 might_sleep(); 11688 11689 /* When called immediately after register_netdevice() failed the unwind 11690 * handling may still be dismantling the device. Handle that case by 11691 * deferring the free. 11692 */ 11693 if (dev->reg_state == NETREG_UNREGISTERING) { 11694 ASSERT_RTNL(); 11695 dev->needs_free_netdev = true; 11696 return; 11697 } 11698 11699 WARN_ON(dev->cfg != dev->cfg_pending); 11700 kfree(dev->cfg); 11701 kfree(dev->ethtool); 11702 netif_free_tx_queues(dev); 11703 netif_free_rx_queues(dev); 11704 11705 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 11706 11707 /* Flush device addresses */ 11708 dev_addr_flush(dev); 11709 11710 netdev_napi_exit(dev); 11711 11712 ref_tracker_dir_exit(&dev->refcnt_tracker); 11713 #ifdef CONFIG_PCPU_DEV_REFCNT 11714 free_percpu(dev->pcpu_refcnt); 11715 dev->pcpu_refcnt = NULL; 11716 #endif 11717 free_percpu(dev->core_stats); 11718 dev->core_stats = NULL; 11719 free_percpu(dev->xdp_bulkq); 11720 dev->xdp_bulkq = NULL; 11721 11722 netdev_free_phy_link_topology(dev); 11723 11724 mutex_destroy(&dev->lock); 11725 11726 /* Compatibility with error handling in drivers */ 11727 if (dev->reg_state == NETREG_UNINITIALIZED || 11728 dev->reg_state == NETREG_DUMMY) { 11729 kvfree(dev); 11730 return; 11731 } 11732 11733 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 11734 WRITE_ONCE(dev->reg_state, NETREG_RELEASED); 11735 11736 /* will free via device release */ 11737 put_device(&dev->dev); 11738 } 11739 EXPORT_SYMBOL(free_netdev); 11740 11741 /** 11742 * alloc_netdev_dummy - Allocate and initialize a dummy net device. 11743 * @sizeof_priv: size of private data to allocate space for 11744 * 11745 * Return: the allocated net_device on success, NULL otherwise 11746 */ 11747 struct net_device *alloc_netdev_dummy(int sizeof_priv) 11748 { 11749 return alloc_netdev(sizeof_priv, "dummy#", NET_NAME_UNKNOWN, 11750 init_dummy_netdev); 11751 } 11752 EXPORT_SYMBOL_GPL(alloc_netdev_dummy); 11753 11754 /** 11755 * synchronize_net - Synchronize with packet receive processing 11756 * 11757 * Wait for packets currently being received to be done. 11758 * Does not block later packets from starting. 11759 */ 11760 void synchronize_net(void) 11761 { 11762 might_sleep(); 11763 if (from_cleanup_net() || rtnl_is_locked()) 11764 synchronize_rcu_expedited(); 11765 else 11766 synchronize_rcu(); 11767 } 11768 EXPORT_SYMBOL(synchronize_net); 11769 11770 static void netdev_rss_contexts_free(struct net_device *dev) 11771 { 11772 struct ethtool_rxfh_context *ctx; 11773 unsigned long context; 11774 11775 mutex_lock(&dev->ethtool->rss_lock); 11776 xa_for_each(&dev->ethtool->rss_ctx, context, ctx) { 11777 struct ethtool_rxfh_param rxfh; 11778 11779 rxfh.indir = ethtool_rxfh_context_indir(ctx); 11780 rxfh.key = ethtool_rxfh_context_key(ctx); 11781 rxfh.hfunc = ctx->hfunc; 11782 rxfh.input_xfrm = ctx->input_xfrm; 11783 rxfh.rss_context = context; 11784 rxfh.rss_delete = true; 11785 11786 xa_erase(&dev->ethtool->rss_ctx, context); 11787 if (dev->ethtool_ops->create_rxfh_context) 11788 dev->ethtool_ops->remove_rxfh_context(dev, ctx, 11789 context, NULL); 11790 else 11791 dev->ethtool_ops->set_rxfh(dev, &rxfh, NULL); 11792 kfree(ctx); 11793 } 11794 xa_destroy(&dev->ethtool->rss_ctx); 11795 mutex_unlock(&dev->ethtool->rss_lock); 11796 } 11797 11798 /** 11799 * unregister_netdevice_queue - remove device from the kernel 11800 * @dev: device 11801 * @head: list 11802 * 11803 * This function shuts down a device interface and removes it 11804 * from the kernel tables. 11805 * If head not NULL, device is queued to be unregistered later. 11806 * 11807 * Callers must hold the rtnl semaphore. You may want 11808 * unregister_netdev() instead of this. 11809 */ 11810 11811 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 11812 { 11813 ASSERT_RTNL(); 11814 11815 if (head) { 11816 list_move_tail(&dev->unreg_list, head); 11817 } else { 11818 LIST_HEAD(single); 11819 11820 list_add(&dev->unreg_list, &single); 11821 unregister_netdevice_many(&single); 11822 } 11823 } 11824 EXPORT_SYMBOL(unregister_netdevice_queue); 11825 11826 void unregister_netdevice_many_notify(struct list_head *head, 11827 u32 portid, const struct nlmsghdr *nlh) 11828 { 11829 struct net_device *dev, *tmp; 11830 LIST_HEAD(close_head); 11831 int cnt = 0; 11832 11833 BUG_ON(dev_boot_phase); 11834 ASSERT_RTNL(); 11835 11836 if (list_empty(head)) 11837 return; 11838 11839 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 11840 /* Some devices call without registering 11841 * for initialization unwind. Remove those 11842 * devices and proceed with the remaining. 11843 */ 11844 if (dev->reg_state == NETREG_UNINITIALIZED) { 11845 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 11846 dev->name, dev); 11847 11848 WARN_ON(1); 11849 list_del(&dev->unreg_list); 11850 continue; 11851 } 11852 dev->dismantle = true; 11853 BUG_ON(dev->reg_state != NETREG_REGISTERED); 11854 } 11855 11856 /* If device is running, close it first. */ 11857 list_for_each_entry(dev, head, unreg_list) 11858 list_add_tail(&dev->close_list, &close_head); 11859 dev_close_many(&close_head, true); 11860 11861 list_for_each_entry(dev, head, unreg_list) { 11862 /* And unlink it from device chain. */ 11863 unlist_netdevice(dev); 11864 netdev_lock(dev); 11865 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERING); 11866 netdev_unlock(dev); 11867 } 11868 flush_all_backlogs(); 11869 11870 synchronize_net(); 11871 11872 list_for_each_entry(dev, head, unreg_list) { 11873 struct sk_buff *skb = NULL; 11874 11875 /* Shutdown queueing discipline. */ 11876 dev_shutdown(dev); 11877 dev_tcx_uninstall(dev); 11878 dev_xdp_uninstall(dev); 11879 bpf_dev_bound_netdev_unregister(dev); 11880 dev_dmabuf_uninstall(dev); 11881 11882 netdev_offload_xstats_disable_all(dev); 11883 11884 /* Notify protocols, that we are about to destroy 11885 * this device. They should clean all the things. 11886 */ 11887 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11888 11889 if (!dev->rtnl_link_ops || 11890 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 11891 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 11892 GFP_KERNEL, NULL, 0, 11893 portid, nlh); 11894 11895 /* 11896 * Flush the unicast and multicast chains 11897 */ 11898 dev_uc_flush(dev); 11899 dev_mc_flush(dev); 11900 11901 netdev_name_node_alt_flush(dev); 11902 netdev_name_node_free(dev->name_node); 11903 11904 netdev_rss_contexts_free(dev); 11905 11906 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 11907 11908 if (dev->netdev_ops->ndo_uninit) 11909 dev->netdev_ops->ndo_uninit(dev); 11910 11911 mutex_destroy(&dev->ethtool->rss_lock); 11912 11913 net_shaper_flush_netdev(dev); 11914 11915 if (skb) 11916 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 11917 11918 /* Notifier chain MUST detach us all upper devices. */ 11919 WARN_ON(netdev_has_any_upper_dev(dev)); 11920 WARN_ON(netdev_has_any_lower_dev(dev)); 11921 11922 /* Remove entries from kobject tree */ 11923 netdev_unregister_kobject(dev); 11924 #ifdef CONFIG_XPS 11925 /* Remove XPS queueing entries */ 11926 netif_reset_xps_queues_gt(dev, 0); 11927 #endif 11928 } 11929 11930 synchronize_net(); 11931 11932 list_for_each_entry(dev, head, unreg_list) { 11933 netdev_put(dev, &dev->dev_registered_tracker); 11934 net_set_todo(dev); 11935 cnt++; 11936 } 11937 atomic_add(cnt, &dev_unreg_count); 11938 11939 list_del(head); 11940 } 11941 11942 /** 11943 * unregister_netdevice_many - unregister many devices 11944 * @head: list of devices 11945 * 11946 * Note: As most callers use a stack allocated list_head, 11947 * we force a list_del() to make sure stack won't be corrupted later. 11948 */ 11949 void unregister_netdevice_many(struct list_head *head) 11950 { 11951 unregister_netdevice_many_notify(head, 0, NULL); 11952 } 11953 EXPORT_SYMBOL(unregister_netdevice_many); 11954 11955 /** 11956 * unregister_netdev - remove device from the kernel 11957 * @dev: device 11958 * 11959 * This function shuts down a device interface and removes it 11960 * from the kernel tables. 11961 * 11962 * This is just a wrapper for unregister_netdevice that takes 11963 * the rtnl semaphore. In general you want to use this and not 11964 * unregister_netdevice. 11965 */ 11966 void unregister_netdev(struct net_device *dev) 11967 { 11968 rtnl_net_dev_lock(dev); 11969 unregister_netdevice(dev); 11970 rtnl_net_dev_unlock(dev); 11971 } 11972 EXPORT_SYMBOL(unregister_netdev); 11973 11974 /** 11975 * __dev_change_net_namespace - move device to different nethost namespace 11976 * @dev: device 11977 * @net: network namespace 11978 * @pat: If not NULL name pattern to try if the current device name 11979 * is already taken in the destination network namespace. 11980 * @new_ifindex: If not zero, specifies device index in the target 11981 * namespace. 11982 * 11983 * This function shuts down a device interface and moves it 11984 * to a new network namespace. On success 0 is returned, on 11985 * a failure a netagive errno code is returned. 11986 * 11987 * Callers must hold the rtnl semaphore. 11988 */ 11989 11990 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 11991 const char *pat, int new_ifindex) 11992 { 11993 struct netdev_name_node *name_node; 11994 struct net *net_old = dev_net(dev); 11995 char new_name[IFNAMSIZ] = {}; 11996 int err, new_nsid; 11997 11998 ASSERT_RTNL(); 11999 12000 /* Don't allow namespace local devices to be moved. */ 12001 err = -EINVAL; 12002 if (dev->netns_local) 12003 goto out; 12004 12005 /* Ensure the device has been registered */ 12006 if (dev->reg_state != NETREG_REGISTERED) 12007 goto out; 12008 12009 /* Get out if there is nothing todo */ 12010 err = 0; 12011 if (net_eq(net_old, net)) 12012 goto out; 12013 12014 /* Pick the destination device name, and ensure 12015 * we can use it in the destination network namespace. 12016 */ 12017 err = -EEXIST; 12018 if (netdev_name_in_use(net, dev->name)) { 12019 /* We get here if we can't use the current device name */ 12020 if (!pat) 12021 goto out; 12022 err = dev_prep_valid_name(net, dev, pat, new_name, EEXIST); 12023 if (err < 0) 12024 goto out; 12025 } 12026 /* Check that none of the altnames conflicts. */ 12027 err = -EEXIST; 12028 netdev_for_each_altname(dev, name_node) 12029 if (netdev_name_in_use(net, name_node->name)) 12030 goto out; 12031 12032 /* Check that new_ifindex isn't used yet. */ 12033 if (new_ifindex) { 12034 err = dev_index_reserve(net, new_ifindex); 12035 if (err < 0) 12036 goto out; 12037 } else { 12038 /* If there is an ifindex conflict assign a new one */ 12039 err = dev_index_reserve(net, dev->ifindex); 12040 if (err == -EBUSY) 12041 err = dev_index_reserve(net, 0); 12042 if (err < 0) 12043 goto out; 12044 new_ifindex = err; 12045 } 12046 12047 /* 12048 * And now a mini version of register_netdevice unregister_netdevice. 12049 */ 12050 12051 /* If device is running close it first. */ 12052 dev_close(dev); 12053 12054 /* And unlink it from device chain */ 12055 unlist_netdevice(dev); 12056 12057 synchronize_net(); 12058 12059 /* Shutdown queueing discipline. */ 12060 dev_shutdown(dev); 12061 12062 /* Notify protocols, that we are about to destroy 12063 * this device. They should clean all the things. 12064 * 12065 * Note that dev->reg_state stays at NETREG_REGISTERED. 12066 * This is wanted because this way 8021q and macvlan know 12067 * the device is just moving and can keep their slaves up. 12068 */ 12069 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 12070 rcu_barrier(); 12071 12072 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 12073 12074 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 12075 new_ifindex); 12076 12077 /* 12078 * Flush the unicast and multicast chains 12079 */ 12080 dev_uc_flush(dev); 12081 dev_mc_flush(dev); 12082 12083 /* Send a netdev-removed uevent to the old namespace */ 12084 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 12085 netdev_adjacent_del_links(dev); 12086 12087 /* Move per-net netdevice notifiers that are following the netdevice */ 12088 move_netdevice_notifiers_dev_net(dev, net); 12089 12090 /* Actually switch the network namespace */ 12091 dev_net_set(dev, net); 12092 dev->ifindex = new_ifindex; 12093 12094 if (new_name[0]) { 12095 /* Rename the netdev to prepared name */ 12096 write_seqlock_bh(&netdev_rename_lock); 12097 strscpy(dev->name, new_name, IFNAMSIZ); 12098 write_sequnlock_bh(&netdev_rename_lock); 12099 } 12100 12101 /* Fixup kobjects */ 12102 dev_set_uevent_suppress(&dev->dev, 1); 12103 err = device_rename(&dev->dev, dev->name); 12104 dev_set_uevent_suppress(&dev->dev, 0); 12105 WARN_ON(err); 12106 12107 /* Send a netdev-add uevent to the new namespace */ 12108 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 12109 netdev_adjacent_add_links(dev); 12110 12111 /* Adapt owner in case owning user namespace of target network 12112 * namespace is different from the original one. 12113 */ 12114 err = netdev_change_owner(dev, net_old, net); 12115 WARN_ON(err); 12116 12117 /* Add the device back in the hashes */ 12118 list_netdevice(dev); 12119 12120 /* Notify protocols, that a new device appeared. */ 12121 call_netdevice_notifiers(NETDEV_REGISTER, dev); 12122 12123 /* 12124 * Prevent userspace races by waiting until the network 12125 * device is fully setup before sending notifications. 12126 */ 12127 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 12128 12129 synchronize_net(); 12130 err = 0; 12131 out: 12132 return err; 12133 } 12134 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 12135 12136 static int dev_cpu_dead(unsigned int oldcpu) 12137 { 12138 struct sk_buff **list_skb; 12139 struct sk_buff *skb; 12140 unsigned int cpu; 12141 struct softnet_data *sd, *oldsd, *remsd = NULL; 12142 12143 local_irq_disable(); 12144 cpu = smp_processor_id(); 12145 sd = &per_cpu(softnet_data, cpu); 12146 oldsd = &per_cpu(softnet_data, oldcpu); 12147 12148 /* Find end of our completion_queue. */ 12149 list_skb = &sd->completion_queue; 12150 while (*list_skb) 12151 list_skb = &(*list_skb)->next; 12152 /* Append completion queue from offline CPU. */ 12153 *list_skb = oldsd->completion_queue; 12154 oldsd->completion_queue = NULL; 12155 12156 /* Append output queue from offline CPU. */ 12157 if (oldsd->output_queue) { 12158 *sd->output_queue_tailp = oldsd->output_queue; 12159 sd->output_queue_tailp = oldsd->output_queue_tailp; 12160 oldsd->output_queue = NULL; 12161 oldsd->output_queue_tailp = &oldsd->output_queue; 12162 } 12163 /* Append NAPI poll list from offline CPU, with one exception : 12164 * process_backlog() must be called by cpu owning percpu backlog. 12165 * We properly handle process_queue & input_pkt_queue later. 12166 */ 12167 while (!list_empty(&oldsd->poll_list)) { 12168 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 12169 struct napi_struct, 12170 poll_list); 12171 12172 list_del_init(&napi->poll_list); 12173 if (napi->poll == process_backlog) 12174 napi->state &= NAPIF_STATE_THREADED; 12175 else 12176 ____napi_schedule(sd, napi); 12177 } 12178 12179 raise_softirq_irqoff(NET_TX_SOFTIRQ); 12180 local_irq_enable(); 12181 12182 if (!use_backlog_threads()) { 12183 #ifdef CONFIG_RPS 12184 remsd = oldsd->rps_ipi_list; 12185 oldsd->rps_ipi_list = NULL; 12186 #endif 12187 /* send out pending IPI's on offline CPU */ 12188 net_rps_send_ipi(remsd); 12189 } 12190 12191 /* Process offline CPU's input_pkt_queue */ 12192 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 12193 netif_rx(skb); 12194 rps_input_queue_head_incr(oldsd); 12195 } 12196 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 12197 netif_rx(skb); 12198 rps_input_queue_head_incr(oldsd); 12199 } 12200 12201 return 0; 12202 } 12203 12204 /** 12205 * netdev_increment_features - increment feature set by one 12206 * @all: current feature set 12207 * @one: new feature set 12208 * @mask: mask feature set 12209 * 12210 * Computes a new feature set after adding a device with feature set 12211 * @one to the master device with current feature set @all. Will not 12212 * enable anything that is off in @mask. Returns the new feature set. 12213 */ 12214 netdev_features_t netdev_increment_features(netdev_features_t all, 12215 netdev_features_t one, netdev_features_t mask) 12216 { 12217 if (mask & NETIF_F_HW_CSUM) 12218 mask |= NETIF_F_CSUM_MASK; 12219 mask |= NETIF_F_VLAN_CHALLENGED; 12220 12221 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 12222 all &= one | ~NETIF_F_ALL_FOR_ALL; 12223 12224 /* If one device supports hw checksumming, set for all. */ 12225 if (all & NETIF_F_HW_CSUM) 12226 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 12227 12228 return all; 12229 } 12230 EXPORT_SYMBOL(netdev_increment_features); 12231 12232 static struct hlist_head * __net_init netdev_create_hash(void) 12233 { 12234 int i; 12235 struct hlist_head *hash; 12236 12237 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 12238 if (hash != NULL) 12239 for (i = 0; i < NETDEV_HASHENTRIES; i++) 12240 INIT_HLIST_HEAD(&hash[i]); 12241 12242 return hash; 12243 } 12244 12245 /* Initialize per network namespace state */ 12246 static int __net_init netdev_init(struct net *net) 12247 { 12248 BUILD_BUG_ON(GRO_HASH_BUCKETS > 12249 8 * sizeof_field(struct napi_struct, gro_bitmask)); 12250 12251 INIT_LIST_HEAD(&net->dev_base_head); 12252 12253 net->dev_name_head = netdev_create_hash(); 12254 if (net->dev_name_head == NULL) 12255 goto err_name; 12256 12257 net->dev_index_head = netdev_create_hash(); 12258 if (net->dev_index_head == NULL) 12259 goto err_idx; 12260 12261 xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1); 12262 12263 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 12264 12265 return 0; 12266 12267 err_idx: 12268 kfree(net->dev_name_head); 12269 err_name: 12270 return -ENOMEM; 12271 } 12272 12273 /** 12274 * netdev_drivername - network driver for the device 12275 * @dev: network device 12276 * 12277 * Determine network driver for device. 12278 */ 12279 const char *netdev_drivername(const struct net_device *dev) 12280 { 12281 const struct device_driver *driver; 12282 const struct device *parent; 12283 const char *empty = ""; 12284 12285 parent = dev->dev.parent; 12286 if (!parent) 12287 return empty; 12288 12289 driver = parent->driver; 12290 if (driver && driver->name) 12291 return driver->name; 12292 return empty; 12293 } 12294 12295 static void __netdev_printk(const char *level, const struct net_device *dev, 12296 struct va_format *vaf) 12297 { 12298 if (dev && dev->dev.parent) { 12299 dev_printk_emit(level[1] - '0', 12300 dev->dev.parent, 12301 "%s %s %s%s: %pV", 12302 dev_driver_string(dev->dev.parent), 12303 dev_name(dev->dev.parent), 12304 netdev_name(dev), netdev_reg_state(dev), 12305 vaf); 12306 } else if (dev) { 12307 printk("%s%s%s: %pV", 12308 level, netdev_name(dev), netdev_reg_state(dev), vaf); 12309 } else { 12310 printk("%s(NULL net_device): %pV", level, vaf); 12311 } 12312 } 12313 12314 void netdev_printk(const char *level, const struct net_device *dev, 12315 const char *format, ...) 12316 { 12317 struct va_format vaf; 12318 va_list args; 12319 12320 va_start(args, format); 12321 12322 vaf.fmt = format; 12323 vaf.va = &args; 12324 12325 __netdev_printk(level, dev, &vaf); 12326 12327 va_end(args); 12328 } 12329 EXPORT_SYMBOL(netdev_printk); 12330 12331 #define define_netdev_printk_level(func, level) \ 12332 void func(const struct net_device *dev, const char *fmt, ...) \ 12333 { \ 12334 struct va_format vaf; \ 12335 va_list args; \ 12336 \ 12337 va_start(args, fmt); \ 12338 \ 12339 vaf.fmt = fmt; \ 12340 vaf.va = &args; \ 12341 \ 12342 __netdev_printk(level, dev, &vaf); \ 12343 \ 12344 va_end(args); \ 12345 } \ 12346 EXPORT_SYMBOL(func); 12347 12348 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 12349 define_netdev_printk_level(netdev_alert, KERN_ALERT); 12350 define_netdev_printk_level(netdev_crit, KERN_CRIT); 12351 define_netdev_printk_level(netdev_err, KERN_ERR); 12352 define_netdev_printk_level(netdev_warn, KERN_WARNING); 12353 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 12354 define_netdev_printk_level(netdev_info, KERN_INFO); 12355 12356 static void __net_exit netdev_exit(struct net *net) 12357 { 12358 kfree(net->dev_name_head); 12359 kfree(net->dev_index_head); 12360 xa_destroy(&net->dev_by_index); 12361 if (net != &init_net) 12362 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 12363 } 12364 12365 static struct pernet_operations __net_initdata netdev_net_ops = { 12366 .init = netdev_init, 12367 .exit = netdev_exit, 12368 }; 12369 12370 static void __net_exit default_device_exit_net(struct net *net) 12371 { 12372 struct netdev_name_node *name_node, *tmp; 12373 struct net_device *dev, *aux; 12374 /* 12375 * Push all migratable network devices back to the 12376 * initial network namespace 12377 */ 12378 ASSERT_RTNL(); 12379 for_each_netdev_safe(net, dev, aux) { 12380 int err; 12381 char fb_name[IFNAMSIZ]; 12382 12383 /* Ignore unmoveable devices (i.e. loopback) */ 12384 if (dev->netns_local) 12385 continue; 12386 12387 /* Leave virtual devices for the generic cleanup */ 12388 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 12389 continue; 12390 12391 /* Push remaining network devices to init_net */ 12392 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 12393 if (netdev_name_in_use(&init_net, fb_name)) 12394 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 12395 12396 netdev_for_each_altname_safe(dev, name_node, tmp) 12397 if (netdev_name_in_use(&init_net, name_node->name)) 12398 __netdev_name_node_alt_destroy(name_node); 12399 12400 err = dev_change_net_namespace(dev, &init_net, fb_name); 12401 if (err) { 12402 pr_emerg("%s: failed to move %s to init_net: %d\n", 12403 __func__, dev->name, err); 12404 BUG(); 12405 } 12406 } 12407 } 12408 12409 static void __net_exit default_device_exit_batch(struct list_head *net_list) 12410 { 12411 /* At exit all network devices most be removed from a network 12412 * namespace. Do this in the reverse order of registration. 12413 * Do this across as many network namespaces as possible to 12414 * improve batching efficiency. 12415 */ 12416 struct net_device *dev; 12417 struct net *net; 12418 LIST_HEAD(dev_kill_list); 12419 12420 rtnl_lock(); 12421 list_for_each_entry(net, net_list, exit_list) { 12422 default_device_exit_net(net); 12423 cond_resched(); 12424 } 12425 12426 list_for_each_entry(net, net_list, exit_list) { 12427 for_each_netdev_reverse(net, dev) { 12428 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 12429 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 12430 else 12431 unregister_netdevice_queue(dev, &dev_kill_list); 12432 } 12433 } 12434 unregister_netdevice_many(&dev_kill_list); 12435 rtnl_unlock(); 12436 } 12437 12438 static struct pernet_operations __net_initdata default_device_ops = { 12439 .exit_batch = default_device_exit_batch, 12440 }; 12441 12442 static void __init net_dev_struct_check(void) 12443 { 12444 /* TX read-mostly hotpath */ 12445 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, priv_flags_fast); 12446 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, netdev_ops); 12447 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, header_ops); 12448 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, _tx); 12449 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, real_num_tx_queues); 12450 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_size); 12451 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_ipv4_max_size); 12452 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_segs); 12453 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_partial_features); 12454 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, num_tc); 12455 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, mtu); 12456 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, needed_headroom); 12457 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tc_to_txq); 12458 #ifdef CONFIG_XPS 12459 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, xps_maps); 12460 #endif 12461 #ifdef CONFIG_NETFILTER_EGRESS 12462 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, nf_hooks_egress); 12463 #endif 12464 #ifdef CONFIG_NET_XGRESS 12465 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tcx_egress); 12466 #endif 12467 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_tx, 160); 12468 12469 /* TXRX read-mostly hotpath */ 12470 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, lstats); 12471 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, state); 12472 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, flags); 12473 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, hard_header_len); 12474 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, features); 12475 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, ip6_ptr); 12476 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 46); 12477 12478 /* RX read-mostly hotpath */ 12479 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ptype_specific); 12480 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ifindex); 12481 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real_num_rx_queues); 12482 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx); 12483 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_max_size); 12484 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_ipv4_max_size); 12485 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler); 12486 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler_data); 12487 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, nd_net); 12488 #ifdef CONFIG_NETPOLL 12489 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, npinfo); 12490 #endif 12491 #ifdef CONFIG_NET_XGRESS 12492 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_ingress); 12493 #endif 12494 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 92); 12495 } 12496 12497 /* 12498 * Initialize the DEV module. At boot time this walks the device list and 12499 * unhooks any devices that fail to initialise (normally hardware not 12500 * present) and leaves us with a valid list of present and active devices. 12501 * 12502 */ 12503 12504 /* We allocate 256 pages for each CPU if PAGE_SHIFT is 12 */ 12505 #define SYSTEM_PERCPU_PAGE_POOL_SIZE ((1 << 20) / PAGE_SIZE) 12506 12507 static int net_page_pool_create(int cpuid) 12508 { 12509 #if IS_ENABLED(CONFIG_PAGE_POOL) 12510 struct page_pool_params page_pool_params = { 12511 .pool_size = SYSTEM_PERCPU_PAGE_POOL_SIZE, 12512 .flags = PP_FLAG_SYSTEM_POOL, 12513 .nid = cpu_to_mem(cpuid), 12514 }; 12515 struct page_pool *pp_ptr; 12516 int err; 12517 12518 pp_ptr = page_pool_create_percpu(&page_pool_params, cpuid); 12519 if (IS_ERR(pp_ptr)) 12520 return -ENOMEM; 12521 12522 err = xdp_reg_page_pool(pp_ptr); 12523 if (err) { 12524 page_pool_destroy(pp_ptr); 12525 return err; 12526 } 12527 12528 per_cpu(system_page_pool, cpuid) = pp_ptr; 12529 #endif 12530 return 0; 12531 } 12532 12533 static int backlog_napi_should_run(unsigned int cpu) 12534 { 12535 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 12536 struct napi_struct *napi = &sd->backlog; 12537 12538 return test_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 12539 } 12540 12541 static void run_backlog_napi(unsigned int cpu) 12542 { 12543 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 12544 12545 napi_threaded_poll_loop(&sd->backlog); 12546 } 12547 12548 static void backlog_napi_setup(unsigned int cpu) 12549 { 12550 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 12551 struct napi_struct *napi = &sd->backlog; 12552 12553 napi->thread = this_cpu_read(backlog_napi); 12554 set_bit(NAPI_STATE_THREADED, &napi->state); 12555 } 12556 12557 static struct smp_hotplug_thread backlog_threads = { 12558 .store = &backlog_napi, 12559 .thread_should_run = backlog_napi_should_run, 12560 .thread_fn = run_backlog_napi, 12561 .thread_comm = "backlog_napi/%u", 12562 .setup = backlog_napi_setup, 12563 }; 12564 12565 /* 12566 * This is called single threaded during boot, so no need 12567 * to take the rtnl semaphore. 12568 */ 12569 static int __init net_dev_init(void) 12570 { 12571 int i, rc = -ENOMEM; 12572 12573 BUG_ON(!dev_boot_phase); 12574 12575 net_dev_struct_check(); 12576 12577 if (dev_proc_init()) 12578 goto out; 12579 12580 if (netdev_kobject_init()) 12581 goto out; 12582 12583 for (i = 0; i < PTYPE_HASH_SIZE; i++) 12584 INIT_LIST_HEAD(&ptype_base[i]); 12585 12586 if (register_pernet_subsys(&netdev_net_ops)) 12587 goto out; 12588 12589 /* 12590 * Initialise the packet receive queues. 12591 */ 12592 12593 flush_backlogs_fallback = flush_backlogs_alloc(); 12594 if (!flush_backlogs_fallback) 12595 goto out; 12596 12597 for_each_possible_cpu(i) { 12598 struct softnet_data *sd = &per_cpu(softnet_data, i); 12599 12600 skb_queue_head_init(&sd->input_pkt_queue); 12601 skb_queue_head_init(&sd->process_queue); 12602 #ifdef CONFIG_XFRM_OFFLOAD 12603 skb_queue_head_init(&sd->xfrm_backlog); 12604 #endif 12605 INIT_LIST_HEAD(&sd->poll_list); 12606 sd->output_queue_tailp = &sd->output_queue; 12607 #ifdef CONFIG_RPS 12608 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 12609 sd->cpu = i; 12610 #endif 12611 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 12612 spin_lock_init(&sd->defer_lock); 12613 12614 init_gro_hash(&sd->backlog); 12615 sd->backlog.poll = process_backlog; 12616 sd->backlog.weight = weight_p; 12617 INIT_LIST_HEAD(&sd->backlog.poll_list); 12618 12619 if (net_page_pool_create(i)) 12620 goto out; 12621 } 12622 if (use_backlog_threads()) 12623 smpboot_register_percpu_thread(&backlog_threads); 12624 12625 dev_boot_phase = 0; 12626 12627 /* The loopback device is special if any other network devices 12628 * is present in a network namespace the loopback device must 12629 * be present. Since we now dynamically allocate and free the 12630 * loopback device ensure this invariant is maintained by 12631 * keeping the loopback device as the first device on the 12632 * list of network devices. Ensuring the loopback devices 12633 * is the first device that appears and the last network device 12634 * that disappears. 12635 */ 12636 if (register_pernet_device(&loopback_net_ops)) 12637 goto out; 12638 12639 if (register_pernet_device(&default_device_ops)) 12640 goto out; 12641 12642 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 12643 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 12644 12645 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 12646 NULL, dev_cpu_dead); 12647 WARN_ON(rc < 0); 12648 rc = 0; 12649 12650 /* avoid static key IPIs to isolated CPUs */ 12651 if (housekeeping_enabled(HK_TYPE_MISC)) 12652 net_enable_timestamp(); 12653 out: 12654 if (rc < 0) { 12655 for_each_possible_cpu(i) { 12656 struct page_pool *pp_ptr; 12657 12658 pp_ptr = per_cpu(system_page_pool, i); 12659 if (!pp_ptr) 12660 continue; 12661 12662 xdp_unreg_page_pool(pp_ptr); 12663 page_pool_destroy(pp_ptr); 12664 per_cpu(system_page_pool, i) = NULL; 12665 } 12666 } 12667 12668 return rc; 12669 } 12670 12671 subsys_initcall(net_dev_init); 12672