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