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