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