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