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