1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * NET3 Protocol independent device support routines. 4 * 5 * Derived from the non IP parts of dev.c 1.0.19 6 * Authors: Ross Biro 7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 8 * Mark Evans, <evansmp@uhura.aston.ac.uk> 9 * 10 * Additional Authors: 11 * Florian la Roche <rzsfl@rz.uni-sb.de> 12 * Alan Cox <gw4pts@gw4pts.ampr.org> 13 * David Hinds <dahinds@users.sourceforge.net> 14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 15 * Adam Sulmicki <adam@cfar.umd.edu> 16 * Pekka Riikonen <priikone@poesidon.pspt.fi> 17 * 18 * Changes: 19 * D.J. Barrow : Fixed bug where dev->refcnt gets set 20 * to 2 if register_netdev gets called 21 * before net_dev_init & also removed a 22 * few lines of code in the process. 23 * Alan Cox : device private ioctl copies fields back. 24 * Alan Cox : Transmit queue code does relevant 25 * stunts to keep the queue safe. 26 * Alan Cox : Fixed double lock. 27 * Alan Cox : Fixed promisc NULL pointer trap 28 * ???????? : Support the full private ioctl range 29 * Alan Cox : Moved ioctl permission check into 30 * drivers 31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 32 * Alan Cox : 100 backlog just doesn't cut it when 33 * you start doing multicast video 8) 34 * Alan Cox : Rewrote net_bh and list manager. 35 * Alan Cox : Fix ETH_P_ALL echoback lengths. 36 * Alan Cox : Took out transmit every packet pass 37 * Saved a few bytes in the ioctl handler 38 * Alan Cox : Network driver sets packet type before 39 * calling netif_rx. Saves a function 40 * call a packet. 41 * Alan Cox : Hashed net_bh() 42 * Richard Kooijman: Timestamp fixes. 43 * Alan Cox : Wrong field in SIOCGIFDSTADDR 44 * Alan Cox : Device lock protection. 45 * Alan Cox : Fixed nasty side effect of device close 46 * changes. 47 * Rudi Cilibrasi : Pass the right thing to 48 * set_mac_address() 49 * Dave Miller : 32bit quantity for the device lock to 50 * make it work out on a Sparc. 51 * Bjorn Ekwall : Added KERNELD hack. 52 * Alan Cox : Cleaned up the backlog initialise. 53 * Craig Metz : SIOCGIFCONF fix if space for under 54 * 1 device. 55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 56 * is no device open function. 57 * Andi Kleen : Fix error reporting for SIOCGIFCONF 58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 59 * Cyrus Durgin : Cleaned for KMOD 60 * Adam Sulmicki : Bug Fix : Network Device Unload 61 * A network device unload needs to purge 62 * the backlog queue. 63 * Paul Rusty Russell : SIOCSIFNAME 64 * Pekka Riikonen : Netdev boot-time settings code 65 * Andrew Morton : Make unregister_netdevice wait 66 * indefinitely on dev->refcnt 67 * J Hadi Salim : - Backlog queue sampling 68 * - netif_rx() feedback 69 */ 70 71 #include <linux/uaccess.h> 72 #include <linux/bitops.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/mm.h> 81 #include <linux/mutex.h> 82 #include <linux/rwsem.h> 83 #include <linux/string.h> 84 #include <linux/mm.h> 85 #include <linux/socket.h> 86 #include <linux/sockios.h> 87 #include <linux/errno.h> 88 #include <linux/interrupt.h> 89 #include <linux/if_ether.h> 90 #include <linux/netdevice.h> 91 #include <linux/etherdevice.h> 92 #include <linux/ethtool.h> 93 #include <linux/skbuff.h> 94 #include <linux/kthread.h> 95 #include <linux/bpf.h> 96 #include <linux/bpf_trace.h> 97 #include <net/net_namespace.h> 98 #include <net/sock.h> 99 #include <net/busy_poll.h> 100 #include <linux/rtnetlink.h> 101 #include <linux/stat.h> 102 #include <net/dsa.h> 103 #include <net/dst.h> 104 #include <net/dst_metadata.h> 105 #include <net/gro.h> 106 #include <net/pkt_sched.h> 107 #include <net/pkt_cls.h> 108 #include <net/checksum.h> 109 #include <net/xfrm.h> 110 #include <linux/highmem.h> 111 #include <linux/init.h> 112 #include <linux/module.h> 113 #include <linux/netpoll.h> 114 #include <linux/rcupdate.h> 115 #include <linux/delay.h> 116 #include <net/iw_handler.h> 117 #include <asm/current.h> 118 #include <linux/audit.h> 119 #include <linux/dmaengine.h> 120 #include <linux/err.h> 121 #include <linux/ctype.h> 122 #include <linux/if_arp.h> 123 #include <linux/if_vlan.h> 124 #include <linux/ip.h> 125 #include <net/ip.h> 126 #include <net/mpls.h> 127 #include <linux/ipv6.h> 128 #include <linux/in.h> 129 #include <linux/jhash.h> 130 #include <linux/random.h> 131 #include <trace/events/napi.h> 132 #include <trace/events/net.h> 133 #include <trace/events/skb.h> 134 #include <trace/events/qdisc.h> 135 #include <linux/inetdevice.h> 136 #include <linux/cpu_rmap.h> 137 #include <linux/static_key.h> 138 #include <linux/hashtable.h> 139 #include <linux/vmalloc.h> 140 #include <linux/if_macvlan.h> 141 #include <linux/errqueue.h> 142 #include <linux/hrtimer.h> 143 #include <linux/netfilter_netdev.h> 144 #include <linux/crash_dump.h> 145 #include <linux/sctp.h> 146 #include <net/udp_tunnel.h> 147 #include <linux/net_namespace.h> 148 #include <linux/indirect_call_wrapper.h> 149 #include <net/devlink.h> 150 #include <linux/pm_runtime.h> 151 #include <linux/prandom.h> 152 #include <linux/once_lite.h> 153 154 #include "dev.h" 155 #include "net-sysfs.h" 156 157 158 static DEFINE_SPINLOCK(ptype_lock); 159 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 160 struct list_head ptype_all __read_mostly; /* Taps */ 161 162 static int netif_rx_internal(struct sk_buff *skb); 163 static int call_netdevice_notifiers_info(unsigned long val, 164 struct netdev_notifier_info *info); 165 static int call_netdevice_notifiers_extack(unsigned long val, 166 struct net_device *dev, 167 struct netlink_ext_ack *extack); 168 static struct napi_struct *napi_by_id(unsigned int napi_id); 169 170 /* 171 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 172 * semaphore. 173 * 174 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 175 * 176 * Writers must hold the rtnl semaphore while they loop through the 177 * dev_base_head list, and hold dev_base_lock for writing when they do the 178 * actual updates. This allows pure readers to access the list even 179 * while a writer is preparing to update it. 180 * 181 * To put it another way, dev_base_lock is held for writing only to 182 * protect against pure readers; the rtnl semaphore provides the 183 * protection against other writers. 184 * 185 * See, for example usages, register_netdevice() and 186 * unregister_netdevice(), which must be called with the rtnl 187 * semaphore held. 188 */ 189 DEFINE_RWLOCK(dev_base_lock); 190 EXPORT_SYMBOL(dev_base_lock); 191 192 static DEFINE_MUTEX(ifalias_mutex); 193 194 /* protects napi_hash addition/deletion and napi_gen_id */ 195 static DEFINE_SPINLOCK(napi_hash_lock); 196 197 static unsigned int napi_gen_id = NR_CPUS; 198 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 199 200 static DECLARE_RWSEM(devnet_rename_sem); 201 202 static inline void dev_base_seq_inc(struct net *net) 203 { 204 while (++net->dev_base_seq == 0) 205 ; 206 } 207 208 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 209 { 210 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 211 212 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 213 } 214 215 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 216 { 217 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 218 } 219 220 static inline void rps_lock_irqsave(struct softnet_data *sd, 221 unsigned long *flags) 222 { 223 if (IS_ENABLED(CONFIG_RPS)) 224 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 225 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 226 local_irq_save(*flags); 227 } 228 229 static inline void rps_lock_irq_disable(struct softnet_data *sd) 230 { 231 if (IS_ENABLED(CONFIG_RPS)) 232 spin_lock_irq(&sd->input_pkt_queue.lock); 233 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 234 local_irq_disable(); 235 } 236 237 static inline void rps_unlock_irq_restore(struct softnet_data *sd, 238 unsigned long *flags) 239 { 240 if (IS_ENABLED(CONFIG_RPS)) 241 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 242 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 243 local_irq_restore(*flags); 244 } 245 246 static inline void rps_unlock_irq_enable(struct softnet_data *sd) 247 { 248 if (IS_ENABLED(CONFIG_RPS)) 249 spin_unlock_irq(&sd->input_pkt_queue.lock); 250 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 251 local_irq_enable(); 252 } 253 254 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 255 const char *name) 256 { 257 struct netdev_name_node *name_node; 258 259 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 260 if (!name_node) 261 return NULL; 262 INIT_HLIST_NODE(&name_node->hlist); 263 name_node->dev = dev; 264 name_node->name = name; 265 return name_node; 266 } 267 268 static struct netdev_name_node * 269 netdev_name_node_head_alloc(struct net_device *dev) 270 { 271 struct netdev_name_node *name_node; 272 273 name_node = netdev_name_node_alloc(dev, dev->name); 274 if (!name_node) 275 return NULL; 276 INIT_LIST_HEAD(&name_node->list); 277 return name_node; 278 } 279 280 static void netdev_name_node_free(struct netdev_name_node *name_node) 281 { 282 kfree(name_node); 283 } 284 285 static void netdev_name_node_add(struct net *net, 286 struct netdev_name_node *name_node) 287 { 288 hlist_add_head_rcu(&name_node->hlist, 289 dev_name_hash(net, name_node->name)); 290 } 291 292 static void netdev_name_node_del(struct netdev_name_node *name_node) 293 { 294 hlist_del_rcu(&name_node->hlist); 295 } 296 297 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 298 const char *name) 299 { 300 struct hlist_head *head = dev_name_hash(net, name); 301 struct netdev_name_node *name_node; 302 303 hlist_for_each_entry(name_node, head, hlist) 304 if (!strcmp(name_node->name, name)) 305 return name_node; 306 return NULL; 307 } 308 309 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 310 const char *name) 311 { 312 struct hlist_head *head = dev_name_hash(net, name); 313 struct netdev_name_node *name_node; 314 315 hlist_for_each_entry_rcu(name_node, head, hlist) 316 if (!strcmp(name_node->name, name)) 317 return name_node; 318 return NULL; 319 } 320 321 bool netdev_name_in_use(struct net *net, const char *name) 322 { 323 return netdev_name_node_lookup(net, name); 324 } 325 EXPORT_SYMBOL(netdev_name_in_use); 326 327 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 328 { 329 struct netdev_name_node *name_node; 330 struct net *net = dev_net(dev); 331 332 name_node = netdev_name_node_lookup(net, name); 333 if (name_node) 334 return -EEXIST; 335 name_node = netdev_name_node_alloc(dev, name); 336 if (!name_node) 337 return -ENOMEM; 338 netdev_name_node_add(net, name_node); 339 /* The node that holds dev->name acts as a head of per-device list. */ 340 list_add_tail(&name_node->list, &dev->name_node->list); 341 342 return 0; 343 } 344 345 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 346 { 347 list_del(&name_node->list); 348 netdev_name_node_del(name_node); 349 kfree(name_node->name); 350 netdev_name_node_free(name_node); 351 } 352 353 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 354 { 355 struct netdev_name_node *name_node; 356 struct net *net = dev_net(dev); 357 358 name_node = netdev_name_node_lookup(net, name); 359 if (!name_node) 360 return -ENOENT; 361 /* lookup might have found our primary name or a name belonging 362 * to another device. 363 */ 364 if (name_node == dev->name_node || name_node->dev != dev) 365 return -EINVAL; 366 367 __netdev_name_node_alt_destroy(name_node); 368 369 return 0; 370 } 371 372 static void netdev_name_node_alt_flush(struct net_device *dev) 373 { 374 struct netdev_name_node *name_node, *tmp; 375 376 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) 377 __netdev_name_node_alt_destroy(name_node); 378 } 379 380 /* Device list insertion */ 381 static void list_netdevice(struct net_device *dev) 382 { 383 struct net *net = dev_net(dev); 384 385 ASSERT_RTNL(); 386 387 write_lock(&dev_base_lock); 388 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 389 netdev_name_node_add(net, dev->name_node); 390 hlist_add_head_rcu(&dev->index_hlist, 391 dev_index_hash(net, dev->ifindex)); 392 write_unlock(&dev_base_lock); 393 394 dev_base_seq_inc(net); 395 } 396 397 /* Device list removal 398 * caller must respect a RCU grace period before freeing/reusing dev 399 */ 400 static void unlist_netdevice(struct net_device *dev, bool lock) 401 { 402 ASSERT_RTNL(); 403 404 /* Unlink dev from the device chain */ 405 if (lock) 406 write_lock(&dev_base_lock); 407 list_del_rcu(&dev->dev_list); 408 netdev_name_node_del(dev->name_node); 409 hlist_del_rcu(&dev->index_hlist); 410 if (lock) 411 write_unlock(&dev_base_lock); 412 413 dev_base_seq_inc(dev_net(dev)); 414 } 415 416 /* 417 * Our notifier list 418 */ 419 420 static RAW_NOTIFIER_HEAD(netdev_chain); 421 422 /* 423 * Device drivers call our routines to queue packets here. We empty the 424 * queue in the local softnet handler. 425 */ 426 427 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 428 EXPORT_PER_CPU_SYMBOL(softnet_data); 429 430 #ifdef CONFIG_LOCKDEP 431 /* 432 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 433 * according to dev->type 434 */ 435 static const unsigned short netdev_lock_type[] = { 436 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 437 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 438 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 439 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 440 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 441 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 442 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 443 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 444 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 445 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 446 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 447 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 448 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 449 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 450 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 451 452 static const char *const netdev_lock_name[] = { 453 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 454 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 455 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 456 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 457 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 458 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 459 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 460 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 461 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 462 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 463 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 464 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 465 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 466 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 467 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 468 469 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 470 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 471 472 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 473 { 474 int i; 475 476 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 477 if (netdev_lock_type[i] == dev_type) 478 return i; 479 /* the last key is used by default */ 480 return ARRAY_SIZE(netdev_lock_type) - 1; 481 } 482 483 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 484 unsigned short dev_type) 485 { 486 int i; 487 488 i = netdev_lock_pos(dev_type); 489 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 490 netdev_lock_name[i]); 491 } 492 493 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 494 { 495 int i; 496 497 i = netdev_lock_pos(dev->type); 498 lockdep_set_class_and_name(&dev->addr_list_lock, 499 &netdev_addr_lock_key[i], 500 netdev_lock_name[i]); 501 } 502 #else 503 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 504 unsigned short dev_type) 505 { 506 } 507 508 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 509 { 510 } 511 #endif 512 513 /******************************************************************************* 514 * 515 * Protocol management and registration routines 516 * 517 *******************************************************************************/ 518 519 520 /* 521 * Add a protocol ID to the list. Now that the input handler is 522 * smarter we can dispense with all the messy stuff that used to be 523 * here. 524 * 525 * BEWARE!!! Protocol handlers, mangling input packets, 526 * MUST BE last in hash buckets and checking protocol handlers 527 * MUST start from promiscuous ptype_all chain in net_bh. 528 * It is true now, do not change it. 529 * Explanation follows: if protocol handler, mangling packet, will 530 * be the first on list, it is not able to sense, that packet 531 * is cloned and should be copied-on-write, so that it will 532 * change it and subsequent readers will get broken packet. 533 * --ANK (980803) 534 */ 535 536 static inline struct list_head *ptype_head(const struct packet_type *pt) 537 { 538 if (pt->type == htons(ETH_P_ALL)) 539 return pt->dev ? &pt->dev->ptype_all : &ptype_all; 540 else 541 return pt->dev ? &pt->dev->ptype_specific : 542 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 543 } 544 545 /** 546 * dev_add_pack - add packet handler 547 * @pt: packet type declaration 548 * 549 * Add a protocol handler to the networking stack. The passed &packet_type 550 * is linked into kernel lists and may not be freed until it has been 551 * removed from the kernel lists. 552 * 553 * This call does not sleep therefore it can not 554 * guarantee all CPU's that are in middle of receiving packets 555 * will see the new packet type (until the next received packet). 556 */ 557 558 void dev_add_pack(struct packet_type *pt) 559 { 560 struct list_head *head = ptype_head(pt); 561 562 spin_lock(&ptype_lock); 563 list_add_rcu(&pt->list, head); 564 spin_unlock(&ptype_lock); 565 } 566 EXPORT_SYMBOL(dev_add_pack); 567 568 /** 569 * __dev_remove_pack - remove packet handler 570 * @pt: packet type declaration 571 * 572 * Remove a protocol handler that was previously added to the kernel 573 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 574 * from the kernel lists and can be freed or reused once this function 575 * returns. 576 * 577 * The packet type might still be in use by receivers 578 * and must not be freed until after all the CPU's have gone 579 * through a quiescent state. 580 */ 581 void __dev_remove_pack(struct packet_type *pt) 582 { 583 struct list_head *head = ptype_head(pt); 584 struct packet_type *pt1; 585 586 spin_lock(&ptype_lock); 587 588 list_for_each_entry(pt1, head, list) { 589 if (pt == pt1) { 590 list_del_rcu(&pt->list); 591 goto out; 592 } 593 } 594 595 pr_warn("dev_remove_pack: %p not found\n", pt); 596 out: 597 spin_unlock(&ptype_lock); 598 } 599 EXPORT_SYMBOL(__dev_remove_pack); 600 601 /** 602 * dev_remove_pack - remove packet handler 603 * @pt: packet type declaration 604 * 605 * Remove a protocol handler that was previously added to the kernel 606 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 607 * from the kernel lists and can be freed or reused once this function 608 * returns. 609 * 610 * This call sleeps to guarantee that no CPU is looking at the packet 611 * type after return. 612 */ 613 void dev_remove_pack(struct packet_type *pt) 614 { 615 __dev_remove_pack(pt); 616 617 synchronize_net(); 618 } 619 EXPORT_SYMBOL(dev_remove_pack); 620 621 622 /******************************************************************************* 623 * 624 * Device Interface Subroutines 625 * 626 *******************************************************************************/ 627 628 /** 629 * dev_get_iflink - get 'iflink' value of a interface 630 * @dev: targeted interface 631 * 632 * Indicates the ifindex the interface is linked to. 633 * Physical interfaces have the same 'ifindex' and 'iflink' values. 634 */ 635 636 int dev_get_iflink(const struct net_device *dev) 637 { 638 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 639 return dev->netdev_ops->ndo_get_iflink(dev); 640 641 return dev->ifindex; 642 } 643 EXPORT_SYMBOL(dev_get_iflink); 644 645 /** 646 * dev_fill_metadata_dst - Retrieve tunnel egress information. 647 * @dev: targeted interface 648 * @skb: The packet. 649 * 650 * For better visibility of tunnel traffic OVS needs to retrieve 651 * egress tunnel information for a packet. Following API allows 652 * user to get this info. 653 */ 654 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 655 { 656 struct ip_tunnel_info *info; 657 658 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 659 return -EINVAL; 660 661 info = skb_tunnel_info_unclone(skb); 662 if (!info) 663 return -ENOMEM; 664 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 665 return -EINVAL; 666 667 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 668 } 669 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 670 671 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 672 { 673 int k = stack->num_paths++; 674 675 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 676 return NULL; 677 678 return &stack->path[k]; 679 } 680 681 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 682 struct net_device_path_stack *stack) 683 { 684 const struct net_device *last_dev; 685 struct net_device_path_ctx ctx = { 686 .dev = dev, 687 }; 688 struct net_device_path *path; 689 int ret = 0; 690 691 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 692 stack->num_paths = 0; 693 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 694 last_dev = ctx.dev; 695 path = dev_fwd_path(stack); 696 if (!path) 697 return -1; 698 699 memset(path, 0, sizeof(struct net_device_path)); 700 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 701 if (ret < 0) 702 return -1; 703 704 if (WARN_ON_ONCE(last_dev == ctx.dev)) 705 return -1; 706 } 707 708 if (!ctx.dev) 709 return ret; 710 711 path = dev_fwd_path(stack); 712 if (!path) 713 return -1; 714 path->type = DEV_PATH_ETHERNET; 715 path->dev = ctx.dev; 716 717 return ret; 718 } 719 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 720 721 /** 722 * __dev_get_by_name - find a device by its name 723 * @net: the applicable net namespace 724 * @name: name to find 725 * 726 * Find an interface by name. Must be called under RTNL semaphore 727 * or @dev_base_lock. If the name is found a pointer to the device 728 * is returned. If the name is not found then %NULL is returned. The 729 * reference counters are not incremented so the caller must be 730 * careful with locks. 731 */ 732 733 struct net_device *__dev_get_by_name(struct net *net, const char *name) 734 { 735 struct netdev_name_node *node_name; 736 737 node_name = netdev_name_node_lookup(net, name); 738 return node_name ? node_name->dev : NULL; 739 } 740 EXPORT_SYMBOL(__dev_get_by_name); 741 742 /** 743 * dev_get_by_name_rcu - find a device by its name 744 * @net: the applicable net namespace 745 * @name: name to find 746 * 747 * Find an interface by name. 748 * If the name is found a pointer to the device is returned. 749 * If the name is not found then %NULL is returned. 750 * The reference counters are not incremented so the caller must be 751 * careful with locks. The caller must hold RCU lock. 752 */ 753 754 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 755 { 756 struct netdev_name_node *node_name; 757 758 node_name = netdev_name_node_lookup_rcu(net, name); 759 return node_name ? node_name->dev : NULL; 760 } 761 EXPORT_SYMBOL(dev_get_by_name_rcu); 762 763 /** 764 * dev_get_by_name - find a device by its name 765 * @net: the applicable net namespace 766 * @name: name to find 767 * 768 * Find an interface by name. This can be called from any 769 * context and does its own locking. The returned handle has 770 * the usage count incremented and the caller must use dev_put() to 771 * release it when it is no longer needed. %NULL is returned if no 772 * matching device is found. 773 */ 774 775 struct net_device *dev_get_by_name(struct net *net, const char *name) 776 { 777 struct net_device *dev; 778 779 rcu_read_lock(); 780 dev = dev_get_by_name_rcu(net, name); 781 dev_hold(dev); 782 rcu_read_unlock(); 783 return dev; 784 } 785 EXPORT_SYMBOL(dev_get_by_name); 786 787 /** 788 * __dev_get_by_index - find a device by its ifindex 789 * @net: the applicable net namespace 790 * @ifindex: index of device 791 * 792 * Search for an interface by index. Returns %NULL if the device 793 * is not found or a pointer to the device. The device has not 794 * had its reference counter increased so the caller must be careful 795 * about locking. The caller must hold either the RTNL semaphore 796 * or @dev_base_lock. 797 */ 798 799 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 800 { 801 struct net_device *dev; 802 struct hlist_head *head = dev_index_hash(net, ifindex); 803 804 hlist_for_each_entry(dev, head, index_hlist) 805 if (dev->ifindex == ifindex) 806 return dev; 807 808 return NULL; 809 } 810 EXPORT_SYMBOL(__dev_get_by_index); 811 812 /** 813 * dev_get_by_index_rcu - find a device by its ifindex 814 * @net: the applicable net namespace 815 * @ifindex: index of device 816 * 817 * Search for an interface by index. Returns %NULL if the device 818 * is not found or a pointer to the device. The device has not 819 * had its reference counter increased so the caller must be careful 820 * about locking. The caller must hold RCU lock. 821 */ 822 823 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 824 { 825 struct net_device *dev; 826 struct hlist_head *head = dev_index_hash(net, ifindex); 827 828 hlist_for_each_entry_rcu(dev, head, index_hlist) 829 if (dev->ifindex == ifindex) 830 return dev; 831 832 return NULL; 833 } 834 EXPORT_SYMBOL(dev_get_by_index_rcu); 835 836 837 /** 838 * dev_get_by_index - find a device by its ifindex 839 * @net: the applicable net namespace 840 * @ifindex: index of device 841 * 842 * Search for an interface by index. Returns NULL if the device 843 * is not found or a pointer to the device. The device returned has 844 * had a reference added and the pointer is safe until the user calls 845 * dev_put to indicate they have finished with it. 846 */ 847 848 struct net_device *dev_get_by_index(struct net *net, int ifindex) 849 { 850 struct net_device *dev; 851 852 rcu_read_lock(); 853 dev = dev_get_by_index_rcu(net, ifindex); 854 dev_hold(dev); 855 rcu_read_unlock(); 856 return dev; 857 } 858 EXPORT_SYMBOL(dev_get_by_index); 859 860 /** 861 * dev_get_by_napi_id - find a device by napi_id 862 * @napi_id: ID of the NAPI struct 863 * 864 * Search for an interface by NAPI ID. Returns %NULL if the device 865 * is not found or a pointer to the device. The device has not had 866 * its reference counter increased so the caller must be careful 867 * about locking. The caller must hold RCU lock. 868 */ 869 870 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 871 { 872 struct napi_struct *napi; 873 874 WARN_ON_ONCE(!rcu_read_lock_held()); 875 876 if (napi_id < MIN_NAPI_ID) 877 return NULL; 878 879 napi = napi_by_id(napi_id); 880 881 return napi ? napi->dev : NULL; 882 } 883 EXPORT_SYMBOL(dev_get_by_napi_id); 884 885 /** 886 * netdev_get_name - get a netdevice name, knowing its ifindex. 887 * @net: network namespace 888 * @name: a pointer to the buffer where the name will be stored. 889 * @ifindex: the ifindex of the interface to get the name from. 890 */ 891 int netdev_get_name(struct net *net, char *name, int ifindex) 892 { 893 struct net_device *dev; 894 int ret; 895 896 down_read(&devnet_rename_sem); 897 rcu_read_lock(); 898 899 dev = dev_get_by_index_rcu(net, ifindex); 900 if (!dev) { 901 ret = -ENODEV; 902 goto out; 903 } 904 905 strcpy(name, dev->name); 906 907 ret = 0; 908 out: 909 rcu_read_unlock(); 910 up_read(&devnet_rename_sem); 911 return ret; 912 } 913 914 /** 915 * dev_getbyhwaddr_rcu - find a device by its hardware address 916 * @net: the applicable net namespace 917 * @type: media type of device 918 * @ha: hardware address 919 * 920 * Search for an interface by MAC address. Returns NULL if the device 921 * is not found or a pointer to the device. 922 * The caller must hold RCU or RTNL. 923 * The returned device has not had its ref count increased 924 * and the caller must therefore be careful about locking 925 * 926 */ 927 928 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 929 const char *ha) 930 { 931 struct net_device *dev; 932 933 for_each_netdev_rcu(net, dev) 934 if (dev->type == type && 935 !memcmp(dev->dev_addr, ha, dev->addr_len)) 936 return dev; 937 938 return NULL; 939 } 940 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 941 942 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 943 { 944 struct net_device *dev, *ret = NULL; 945 946 rcu_read_lock(); 947 for_each_netdev_rcu(net, dev) 948 if (dev->type == type) { 949 dev_hold(dev); 950 ret = dev; 951 break; 952 } 953 rcu_read_unlock(); 954 return ret; 955 } 956 EXPORT_SYMBOL(dev_getfirstbyhwtype); 957 958 /** 959 * __dev_get_by_flags - find any device with given flags 960 * @net: the applicable net namespace 961 * @if_flags: IFF_* values 962 * @mask: bitmask of bits in if_flags to check 963 * 964 * Search for any interface with the given flags. Returns NULL if a device 965 * is not found or a pointer to the device. Must be called inside 966 * rtnl_lock(), and result refcount is unchanged. 967 */ 968 969 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 970 unsigned short mask) 971 { 972 struct net_device *dev, *ret; 973 974 ASSERT_RTNL(); 975 976 ret = NULL; 977 for_each_netdev(net, dev) { 978 if (((dev->flags ^ if_flags) & mask) == 0) { 979 ret = dev; 980 break; 981 } 982 } 983 return ret; 984 } 985 EXPORT_SYMBOL(__dev_get_by_flags); 986 987 /** 988 * dev_valid_name - check if name is okay for network device 989 * @name: name string 990 * 991 * Network device names need to be valid file names to 992 * allow sysfs to work. We also disallow any kind of 993 * whitespace. 994 */ 995 bool dev_valid_name(const char *name) 996 { 997 if (*name == '\0') 998 return false; 999 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1000 return false; 1001 if (!strcmp(name, ".") || !strcmp(name, "..")) 1002 return false; 1003 1004 while (*name) { 1005 if (*name == '/' || *name == ':' || isspace(*name)) 1006 return false; 1007 name++; 1008 } 1009 return true; 1010 } 1011 EXPORT_SYMBOL(dev_valid_name); 1012 1013 /** 1014 * __dev_alloc_name - allocate a name for a device 1015 * @net: network namespace to allocate the device name in 1016 * @name: name format string 1017 * @buf: scratch buffer and result name string 1018 * 1019 * Passed a format string - eg "lt%d" it will try and find a suitable 1020 * id. It scans list of devices to build up a free map, then chooses 1021 * the first empty slot. The caller must hold the dev_base or rtnl lock 1022 * while allocating the name and adding the device in order to avoid 1023 * duplicates. 1024 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1025 * Returns the number of the unit assigned or a negative errno code. 1026 */ 1027 1028 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 1029 { 1030 int i = 0; 1031 const char *p; 1032 const int max_netdevices = 8*PAGE_SIZE; 1033 unsigned long *inuse; 1034 struct net_device *d; 1035 1036 if (!dev_valid_name(name)) 1037 return -EINVAL; 1038 1039 p = strchr(name, '%'); 1040 if (p) { 1041 /* 1042 * Verify the string as this thing may have come from 1043 * the user. There must be either one "%d" and no other "%" 1044 * characters. 1045 */ 1046 if (p[1] != 'd' || strchr(p + 2, '%')) 1047 return -EINVAL; 1048 1049 /* Use one page as a bit array of possible slots */ 1050 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 1051 if (!inuse) 1052 return -ENOMEM; 1053 1054 for_each_netdev(net, d) { 1055 struct netdev_name_node *name_node; 1056 list_for_each_entry(name_node, &d->name_node->list, list) { 1057 if (!sscanf(name_node->name, name, &i)) 1058 continue; 1059 if (i < 0 || i >= max_netdevices) 1060 continue; 1061 1062 /* avoid cases where sscanf is not exact inverse of printf */ 1063 snprintf(buf, IFNAMSIZ, name, i); 1064 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1065 __set_bit(i, inuse); 1066 } 1067 if (!sscanf(d->name, name, &i)) 1068 continue; 1069 if (i < 0 || i >= max_netdevices) 1070 continue; 1071 1072 /* avoid cases where sscanf is not exact inverse of printf */ 1073 snprintf(buf, IFNAMSIZ, name, i); 1074 if (!strncmp(buf, d->name, IFNAMSIZ)) 1075 __set_bit(i, inuse); 1076 } 1077 1078 i = find_first_zero_bit(inuse, max_netdevices); 1079 free_page((unsigned long) inuse); 1080 } 1081 1082 snprintf(buf, IFNAMSIZ, name, i); 1083 if (!netdev_name_in_use(net, buf)) 1084 return i; 1085 1086 /* It is possible to run out of possible slots 1087 * when the name is long and there isn't enough space left 1088 * for the digits, or if all bits are used. 1089 */ 1090 return -ENFILE; 1091 } 1092 1093 static int dev_alloc_name_ns(struct net *net, 1094 struct net_device *dev, 1095 const char *name) 1096 { 1097 char buf[IFNAMSIZ]; 1098 int ret; 1099 1100 BUG_ON(!net); 1101 ret = __dev_alloc_name(net, name, buf); 1102 if (ret >= 0) 1103 strscpy(dev->name, buf, IFNAMSIZ); 1104 return ret; 1105 } 1106 1107 /** 1108 * dev_alloc_name - allocate a name for a device 1109 * @dev: device 1110 * @name: name format string 1111 * 1112 * Passed a format string - eg "lt%d" it will try and find a suitable 1113 * id. It scans list of devices to build up a free map, then chooses 1114 * the first empty slot. The caller must hold the dev_base or rtnl lock 1115 * while allocating the name and adding the device in order to avoid 1116 * duplicates. 1117 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1118 * Returns the number of the unit assigned or a negative errno code. 1119 */ 1120 1121 int dev_alloc_name(struct net_device *dev, const char *name) 1122 { 1123 return dev_alloc_name_ns(dev_net(dev), dev, name); 1124 } 1125 EXPORT_SYMBOL(dev_alloc_name); 1126 1127 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1128 const char *name) 1129 { 1130 BUG_ON(!net); 1131 1132 if (!dev_valid_name(name)) 1133 return -EINVAL; 1134 1135 if (strchr(name, '%')) 1136 return dev_alloc_name_ns(net, dev, name); 1137 else if (netdev_name_in_use(net, name)) 1138 return -EEXIST; 1139 else if (dev->name != name) 1140 strscpy(dev->name, name, IFNAMSIZ); 1141 1142 return 0; 1143 } 1144 1145 /** 1146 * dev_change_name - change name of a device 1147 * @dev: device 1148 * @newname: name (or format string) must be at least IFNAMSIZ 1149 * 1150 * Change name of a device, can pass format strings "eth%d". 1151 * for wildcarding. 1152 */ 1153 int dev_change_name(struct net_device *dev, const char *newname) 1154 { 1155 unsigned char old_assign_type; 1156 char oldname[IFNAMSIZ]; 1157 int err = 0; 1158 int ret; 1159 struct net *net; 1160 1161 ASSERT_RTNL(); 1162 BUG_ON(!dev_net(dev)); 1163 1164 net = dev_net(dev); 1165 1166 /* Some auto-enslaved devices e.g. failover slaves are 1167 * special, as userspace might rename the device after 1168 * the interface had been brought up and running since 1169 * the point kernel initiated auto-enslavement. Allow 1170 * live name change even when these slave devices are 1171 * up and running. 1172 * 1173 * Typically, users of these auto-enslaving devices 1174 * don't actually care about slave name change, as 1175 * they are supposed to operate on master interface 1176 * directly. 1177 */ 1178 if (dev->flags & IFF_UP && 1179 likely(!(dev->priv_flags & IFF_LIVE_RENAME_OK))) 1180 return -EBUSY; 1181 1182 down_write(&devnet_rename_sem); 1183 1184 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1185 up_write(&devnet_rename_sem); 1186 return 0; 1187 } 1188 1189 memcpy(oldname, dev->name, IFNAMSIZ); 1190 1191 err = dev_get_valid_name(net, dev, newname); 1192 if (err < 0) { 1193 up_write(&devnet_rename_sem); 1194 return err; 1195 } 1196 1197 if (oldname[0] && !strchr(oldname, '%')) 1198 netdev_info(dev, "renamed from %s\n", oldname); 1199 1200 old_assign_type = dev->name_assign_type; 1201 dev->name_assign_type = NET_NAME_RENAMED; 1202 1203 rollback: 1204 ret = device_rename(&dev->dev, dev->name); 1205 if (ret) { 1206 memcpy(dev->name, oldname, IFNAMSIZ); 1207 dev->name_assign_type = old_assign_type; 1208 up_write(&devnet_rename_sem); 1209 return ret; 1210 } 1211 1212 up_write(&devnet_rename_sem); 1213 1214 netdev_adjacent_rename_links(dev, oldname); 1215 1216 write_lock(&dev_base_lock); 1217 netdev_name_node_del(dev->name_node); 1218 write_unlock(&dev_base_lock); 1219 1220 synchronize_rcu(); 1221 1222 write_lock(&dev_base_lock); 1223 netdev_name_node_add(net, dev->name_node); 1224 write_unlock(&dev_base_lock); 1225 1226 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1227 ret = notifier_to_errno(ret); 1228 1229 if (ret) { 1230 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1231 if (err >= 0) { 1232 err = ret; 1233 down_write(&devnet_rename_sem); 1234 memcpy(dev->name, oldname, IFNAMSIZ); 1235 memcpy(oldname, newname, IFNAMSIZ); 1236 dev->name_assign_type = old_assign_type; 1237 old_assign_type = NET_NAME_RENAMED; 1238 goto rollback; 1239 } else { 1240 netdev_err(dev, "name change rollback failed: %d\n", 1241 ret); 1242 } 1243 } 1244 1245 return err; 1246 } 1247 1248 /** 1249 * dev_set_alias - change ifalias of a device 1250 * @dev: device 1251 * @alias: name up to IFALIASZ 1252 * @len: limit of bytes to copy from info 1253 * 1254 * Set ifalias for a device, 1255 */ 1256 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1257 { 1258 struct dev_ifalias *new_alias = NULL; 1259 1260 if (len >= IFALIASZ) 1261 return -EINVAL; 1262 1263 if (len) { 1264 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1265 if (!new_alias) 1266 return -ENOMEM; 1267 1268 memcpy(new_alias->ifalias, alias, len); 1269 new_alias->ifalias[len] = 0; 1270 } 1271 1272 mutex_lock(&ifalias_mutex); 1273 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1274 mutex_is_locked(&ifalias_mutex)); 1275 mutex_unlock(&ifalias_mutex); 1276 1277 if (new_alias) 1278 kfree_rcu(new_alias, rcuhead); 1279 1280 return len; 1281 } 1282 EXPORT_SYMBOL(dev_set_alias); 1283 1284 /** 1285 * dev_get_alias - get ifalias of a device 1286 * @dev: device 1287 * @name: buffer to store name of ifalias 1288 * @len: size of buffer 1289 * 1290 * get ifalias for a device. Caller must make sure dev cannot go 1291 * away, e.g. rcu read lock or own a reference count to device. 1292 */ 1293 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1294 { 1295 const struct dev_ifalias *alias; 1296 int ret = 0; 1297 1298 rcu_read_lock(); 1299 alias = rcu_dereference(dev->ifalias); 1300 if (alias) 1301 ret = snprintf(name, len, "%s", alias->ifalias); 1302 rcu_read_unlock(); 1303 1304 return ret; 1305 } 1306 1307 /** 1308 * netdev_features_change - device changes features 1309 * @dev: device to cause notification 1310 * 1311 * Called to indicate a device has changed features. 1312 */ 1313 void netdev_features_change(struct net_device *dev) 1314 { 1315 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1316 } 1317 EXPORT_SYMBOL(netdev_features_change); 1318 1319 /** 1320 * netdev_state_change - device changes state 1321 * @dev: device to cause notification 1322 * 1323 * Called to indicate a device has changed state. This function calls 1324 * the notifier chains for netdev_chain and sends a NEWLINK message 1325 * to the routing socket. 1326 */ 1327 void netdev_state_change(struct net_device *dev) 1328 { 1329 if (dev->flags & IFF_UP) { 1330 struct netdev_notifier_change_info change_info = { 1331 .info.dev = dev, 1332 }; 1333 1334 call_netdevice_notifiers_info(NETDEV_CHANGE, 1335 &change_info.info); 1336 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL); 1337 } 1338 } 1339 EXPORT_SYMBOL(netdev_state_change); 1340 1341 /** 1342 * __netdev_notify_peers - notify network peers about existence of @dev, 1343 * to be called when rtnl lock is already held. 1344 * @dev: network device 1345 * 1346 * Generate traffic such that interested network peers are aware of 1347 * @dev, such as by generating a gratuitous ARP. This may be used when 1348 * a device wants to inform the rest of the network about some sort of 1349 * reconfiguration such as a failover event or virtual machine 1350 * migration. 1351 */ 1352 void __netdev_notify_peers(struct net_device *dev) 1353 { 1354 ASSERT_RTNL(); 1355 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1356 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1357 } 1358 EXPORT_SYMBOL(__netdev_notify_peers); 1359 1360 /** 1361 * netdev_notify_peers - notify network peers about existence of @dev 1362 * @dev: network device 1363 * 1364 * Generate traffic such that interested network peers are aware of 1365 * @dev, such as by generating a gratuitous ARP. This may be used when 1366 * a device wants to inform the rest of the network about some sort of 1367 * reconfiguration such as a failover event or virtual machine 1368 * migration. 1369 */ 1370 void netdev_notify_peers(struct net_device *dev) 1371 { 1372 rtnl_lock(); 1373 __netdev_notify_peers(dev); 1374 rtnl_unlock(); 1375 } 1376 EXPORT_SYMBOL(netdev_notify_peers); 1377 1378 static int napi_threaded_poll(void *data); 1379 1380 static int napi_kthread_create(struct napi_struct *n) 1381 { 1382 int err = 0; 1383 1384 /* Create and wake up the kthread once to put it in 1385 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1386 * warning and work with loadavg. 1387 */ 1388 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1389 n->dev->name, n->napi_id); 1390 if (IS_ERR(n->thread)) { 1391 err = PTR_ERR(n->thread); 1392 pr_err("kthread_run failed with err %d\n", err); 1393 n->thread = NULL; 1394 } 1395 1396 return err; 1397 } 1398 1399 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1400 { 1401 const struct net_device_ops *ops = dev->netdev_ops; 1402 int ret; 1403 1404 ASSERT_RTNL(); 1405 dev_addr_check(dev); 1406 1407 if (!netif_device_present(dev)) { 1408 /* may be detached because parent is runtime-suspended */ 1409 if (dev->dev.parent) 1410 pm_runtime_resume(dev->dev.parent); 1411 if (!netif_device_present(dev)) 1412 return -ENODEV; 1413 } 1414 1415 /* Block netpoll from trying to do any rx path servicing. 1416 * If we don't do this there is a chance ndo_poll_controller 1417 * or ndo_poll may be running while we open the device 1418 */ 1419 netpoll_poll_disable(dev); 1420 1421 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1422 ret = notifier_to_errno(ret); 1423 if (ret) 1424 return ret; 1425 1426 set_bit(__LINK_STATE_START, &dev->state); 1427 1428 if (ops->ndo_validate_addr) 1429 ret = ops->ndo_validate_addr(dev); 1430 1431 if (!ret && ops->ndo_open) 1432 ret = ops->ndo_open(dev); 1433 1434 netpoll_poll_enable(dev); 1435 1436 if (ret) 1437 clear_bit(__LINK_STATE_START, &dev->state); 1438 else { 1439 dev->flags |= IFF_UP; 1440 dev_set_rx_mode(dev); 1441 dev_activate(dev); 1442 add_device_randomness(dev->dev_addr, dev->addr_len); 1443 } 1444 1445 return ret; 1446 } 1447 1448 /** 1449 * dev_open - prepare an interface for use. 1450 * @dev: device to open 1451 * @extack: netlink extended ack 1452 * 1453 * Takes a device from down to up state. The device's private open 1454 * function is invoked and then the multicast lists are loaded. Finally 1455 * the device is moved into the up state and a %NETDEV_UP message is 1456 * sent to the netdev notifier chain. 1457 * 1458 * Calling this function on an active interface is a nop. On a failure 1459 * a negative errno code is returned. 1460 */ 1461 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1462 { 1463 int ret; 1464 1465 if (dev->flags & IFF_UP) 1466 return 0; 1467 1468 ret = __dev_open(dev, extack); 1469 if (ret < 0) 1470 return ret; 1471 1472 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); 1473 call_netdevice_notifiers(NETDEV_UP, dev); 1474 1475 return ret; 1476 } 1477 EXPORT_SYMBOL(dev_open); 1478 1479 static void __dev_close_many(struct list_head *head) 1480 { 1481 struct net_device *dev; 1482 1483 ASSERT_RTNL(); 1484 might_sleep(); 1485 1486 list_for_each_entry(dev, head, close_list) { 1487 /* Temporarily disable netpoll until the interface is down */ 1488 netpoll_poll_disable(dev); 1489 1490 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1491 1492 clear_bit(__LINK_STATE_START, &dev->state); 1493 1494 /* Synchronize to scheduled poll. We cannot touch poll list, it 1495 * can be even on different cpu. So just clear netif_running(). 1496 * 1497 * dev->stop() will invoke napi_disable() on all of it's 1498 * napi_struct instances on this device. 1499 */ 1500 smp_mb__after_atomic(); /* Commit netif_running(). */ 1501 } 1502 1503 dev_deactivate_many(head); 1504 1505 list_for_each_entry(dev, head, close_list) { 1506 const struct net_device_ops *ops = dev->netdev_ops; 1507 1508 /* 1509 * Call the device specific close. This cannot fail. 1510 * Only if device is UP 1511 * 1512 * We allow it to be called even after a DETACH hot-plug 1513 * event. 1514 */ 1515 if (ops->ndo_stop) 1516 ops->ndo_stop(dev); 1517 1518 dev->flags &= ~IFF_UP; 1519 netpoll_poll_enable(dev); 1520 } 1521 } 1522 1523 static void __dev_close(struct net_device *dev) 1524 { 1525 LIST_HEAD(single); 1526 1527 list_add(&dev->close_list, &single); 1528 __dev_close_many(&single); 1529 list_del(&single); 1530 } 1531 1532 void dev_close_many(struct list_head *head, bool unlink) 1533 { 1534 struct net_device *dev, *tmp; 1535 1536 /* Remove the devices that don't need to be closed */ 1537 list_for_each_entry_safe(dev, tmp, head, close_list) 1538 if (!(dev->flags & IFF_UP)) 1539 list_del_init(&dev->close_list); 1540 1541 __dev_close_many(head); 1542 1543 list_for_each_entry_safe(dev, tmp, head, close_list) { 1544 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); 1545 call_netdevice_notifiers(NETDEV_DOWN, dev); 1546 if (unlink) 1547 list_del_init(&dev->close_list); 1548 } 1549 } 1550 EXPORT_SYMBOL(dev_close_many); 1551 1552 /** 1553 * dev_close - shutdown an interface. 1554 * @dev: device to shutdown 1555 * 1556 * This function moves an active device into down state. A 1557 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1558 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1559 * chain. 1560 */ 1561 void dev_close(struct net_device *dev) 1562 { 1563 if (dev->flags & IFF_UP) { 1564 LIST_HEAD(single); 1565 1566 list_add(&dev->close_list, &single); 1567 dev_close_many(&single, true); 1568 list_del(&single); 1569 } 1570 } 1571 EXPORT_SYMBOL(dev_close); 1572 1573 1574 /** 1575 * dev_disable_lro - disable Large Receive Offload on a device 1576 * @dev: device 1577 * 1578 * Disable Large Receive Offload (LRO) on a net device. Must be 1579 * called under RTNL. This is needed if received packets may be 1580 * forwarded to another interface. 1581 */ 1582 void dev_disable_lro(struct net_device *dev) 1583 { 1584 struct net_device *lower_dev; 1585 struct list_head *iter; 1586 1587 dev->wanted_features &= ~NETIF_F_LRO; 1588 netdev_update_features(dev); 1589 1590 if (unlikely(dev->features & NETIF_F_LRO)) 1591 netdev_WARN(dev, "failed to disable LRO!\n"); 1592 1593 netdev_for_each_lower_dev(dev, lower_dev, iter) 1594 dev_disable_lro(lower_dev); 1595 } 1596 EXPORT_SYMBOL(dev_disable_lro); 1597 1598 /** 1599 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1600 * @dev: device 1601 * 1602 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1603 * called under RTNL. This is needed if Generic XDP is installed on 1604 * the device. 1605 */ 1606 static void dev_disable_gro_hw(struct net_device *dev) 1607 { 1608 dev->wanted_features &= ~NETIF_F_GRO_HW; 1609 netdev_update_features(dev); 1610 1611 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1612 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1613 } 1614 1615 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1616 { 1617 #define N(val) \ 1618 case NETDEV_##val: \ 1619 return "NETDEV_" __stringify(val); 1620 switch (cmd) { 1621 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1622 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1623 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1624 N(POST_INIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) N(CHANGEUPPER) 1625 N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) N(BONDING_INFO) 1626 N(PRECHANGEUPPER) N(CHANGELOWERSTATE) N(UDP_TUNNEL_PUSH_INFO) 1627 N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1628 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1629 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1630 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1631 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1632 } 1633 #undef N 1634 return "UNKNOWN_NETDEV_EVENT"; 1635 } 1636 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1637 1638 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1639 struct net_device *dev) 1640 { 1641 struct netdev_notifier_info info = { 1642 .dev = dev, 1643 }; 1644 1645 return nb->notifier_call(nb, val, &info); 1646 } 1647 1648 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1649 struct net_device *dev) 1650 { 1651 int err; 1652 1653 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1654 err = notifier_to_errno(err); 1655 if (err) 1656 return err; 1657 1658 if (!(dev->flags & IFF_UP)) 1659 return 0; 1660 1661 call_netdevice_notifier(nb, NETDEV_UP, dev); 1662 return 0; 1663 } 1664 1665 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1666 struct net_device *dev) 1667 { 1668 if (dev->flags & IFF_UP) { 1669 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1670 dev); 1671 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1672 } 1673 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1674 } 1675 1676 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1677 struct net *net) 1678 { 1679 struct net_device *dev; 1680 int err; 1681 1682 for_each_netdev(net, dev) { 1683 err = call_netdevice_register_notifiers(nb, dev); 1684 if (err) 1685 goto rollback; 1686 } 1687 return 0; 1688 1689 rollback: 1690 for_each_netdev_continue_reverse(net, dev) 1691 call_netdevice_unregister_notifiers(nb, dev); 1692 return err; 1693 } 1694 1695 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1696 struct net *net) 1697 { 1698 struct net_device *dev; 1699 1700 for_each_netdev(net, dev) 1701 call_netdevice_unregister_notifiers(nb, dev); 1702 } 1703 1704 static int dev_boot_phase = 1; 1705 1706 /** 1707 * register_netdevice_notifier - register a network notifier block 1708 * @nb: notifier 1709 * 1710 * Register a notifier to be called when network device events occur. 1711 * The notifier passed is linked into the kernel structures and must 1712 * not be reused until it has been unregistered. A negative errno code 1713 * is returned on a failure. 1714 * 1715 * When registered all registration and up events are replayed 1716 * to the new notifier to allow device to have a race free 1717 * view of the network device list. 1718 */ 1719 1720 int register_netdevice_notifier(struct notifier_block *nb) 1721 { 1722 struct net *net; 1723 int err; 1724 1725 /* Close race with setup_net() and cleanup_net() */ 1726 down_write(&pernet_ops_rwsem); 1727 rtnl_lock(); 1728 err = raw_notifier_chain_register(&netdev_chain, nb); 1729 if (err) 1730 goto unlock; 1731 if (dev_boot_phase) 1732 goto unlock; 1733 for_each_net(net) { 1734 err = call_netdevice_register_net_notifiers(nb, net); 1735 if (err) 1736 goto rollback; 1737 } 1738 1739 unlock: 1740 rtnl_unlock(); 1741 up_write(&pernet_ops_rwsem); 1742 return err; 1743 1744 rollback: 1745 for_each_net_continue_reverse(net) 1746 call_netdevice_unregister_net_notifiers(nb, net); 1747 1748 raw_notifier_chain_unregister(&netdev_chain, nb); 1749 goto unlock; 1750 } 1751 EXPORT_SYMBOL(register_netdevice_notifier); 1752 1753 /** 1754 * unregister_netdevice_notifier - unregister a network notifier block 1755 * @nb: notifier 1756 * 1757 * Unregister a notifier previously registered by 1758 * register_netdevice_notifier(). The notifier is unlinked into the 1759 * kernel structures and may then be reused. A negative errno code 1760 * is returned on a failure. 1761 * 1762 * After unregistering unregister and down device events are synthesized 1763 * for all devices on the device list to the removed notifier to remove 1764 * the need for special case cleanup code. 1765 */ 1766 1767 int unregister_netdevice_notifier(struct notifier_block *nb) 1768 { 1769 struct net *net; 1770 int err; 1771 1772 /* Close race with setup_net() and cleanup_net() */ 1773 down_write(&pernet_ops_rwsem); 1774 rtnl_lock(); 1775 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1776 if (err) 1777 goto unlock; 1778 1779 for_each_net(net) 1780 call_netdevice_unregister_net_notifiers(nb, net); 1781 1782 unlock: 1783 rtnl_unlock(); 1784 up_write(&pernet_ops_rwsem); 1785 return err; 1786 } 1787 EXPORT_SYMBOL(unregister_netdevice_notifier); 1788 1789 static int __register_netdevice_notifier_net(struct net *net, 1790 struct notifier_block *nb, 1791 bool ignore_call_fail) 1792 { 1793 int err; 1794 1795 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1796 if (err) 1797 return err; 1798 if (dev_boot_phase) 1799 return 0; 1800 1801 err = call_netdevice_register_net_notifiers(nb, net); 1802 if (err && !ignore_call_fail) 1803 goto chain_unregister; 1804 1805 return 0; 1806 1807 chain_unregister: 1808 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1809 return err; 1810 } 1811 1812 static int __unregister_netdevice_notifier_net(struct net *net, 1813 struct notifier_block *nb) 1814 { 1815 int err; 1816 1817 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1818 if (err) 1819 return err; 1820 1821 call_netdevice_unregister_net_notifiers(nb, net); 1822 return 0; 1823 } 1824 1825 /** 1826 * register_netdevice_notifier_net - register a per-netns network notifier block 1827 * @net: network namespace 1828 * @nb: notifier 1829 * 1830 * Register a notifier to be called when network device events occur. 1831 * The notifier passed is linked into the kernel structures and must 1832 * not be reused until it has been unregistered. A negative errno code 1833 * is returned on a failure. 1834 * 1835 * When registered all registration and up events are replayed 1836 * to the new notifier to allow device to have a race free 1837 * view of the network device list. 1838 */ 1839 1840 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1841 { 1842 int err; 1843 1844 rtnl_lock(); 1845 err = __register_netdevice_notifier_net(net, nb, false); 1846 rtnl_unlock(); 1847 return err; 1848 } 1849 EXPORT_SYMBOL(register_netdevice_notifier_net); 1850 1851 /** 1852 * unregister_netdevice_notifier_net - unregister a per-netns 1853 * network notifier block 1854 * @net: network namespace 1855 * @nb: notifier 1856 * 1857 * Unregister a notifier previously registered by 1858 * register_netdevice_notifier(). The notifier is unlinked into the 1859 * kernel structures and may then be reused. A negative errno code 1860 * is returned on a failure. 1861 * 1862 * After unregistering unregister and down device events are synthesized 1863 * for all devices on the device list to the removed notifier to remove 1864 * the need for special case cleanup code. 1865 */ 1866 1867 int unregister_netdevice_notifier_net(struct net *net, 1868 struct notifier_block *nb) 1869 { 1870 int err; 1871 1872 rtnl_lock(); 1873 err = __unregister_netdevice_notifier_net(net, nb); 1874 rtnl_unlock(); 1875 return err; 1876 } 1877 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1878 1879 int register_netdevice_notifier_dev_net(struct net_device *dev, 1880 struct notifier_block *nb, 1881 struct netdev_net_notifier *nn) 1882 { 1883 int err; 1884 1885 rtnl_lock(); 1886 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1887 if (!err) { 1888 nn->nb = nb; 1889 list_add(&nn->list, &dev->net_notifier_list); 1890 } 1891 rtnl_unlock(); 1892 return err; 1893 } 1894 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1895 1896 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1897 struct notifier_block *nb, 1898 struct netdev_net_notifier *nn) 1899 { 1900 int err; 1901 1902 rtnl_lock(); 1903 list_del(&nn->list); 1904 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1905 rtnl_unlock(); 1906 return err; 1907 } 1908 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1909 1910 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1911 struct net *net) 1912 { 1913 struct netdev_net_notifier *nn; 1914 1915 list_for_each_entry(nn, &dev->net_notifier_list, list) { 1916 __unregister_netdevice_notifier_net(dev_net(dev), nn->nb); 1917 __register_netdevice_notifier_net(net, nn->nb, true); 1918 } 1919 } 1920 1921 /** 1922 * call_netdevice_notifiers_info - call all network notifier blocks 1923 * @val: value passed unmodified to notifier function 1924 * @info: notifier information data 1925 * 1926 * Call all network notifier blocks. Parameters and return value 1927 * are as for raw_notifier_call_chain(). 1928 */ 1929 1930 static int call_netdevice_notifiers_info(unsigned long val, 1931 struct netdev_notifier_info *info) 1932 { 1933 struct net *net = dev_net(info->dev); 1934 int ret; 1935 1936 ASSERT_RTNL(); 1937 1938 /* Run per-netns notifier block chain first, then run the global one. 1939 * Hopefully, one day, the global one is going to be removed after 1940 * all notifier block registrators get converted to be per-netns. 1941 */ 1942 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1943 if (ret & NOTIFY_STOP_MASK) 1944 return ret; 1945 return raw_notifier_call_chain(&netdev_chain, val, info); 1946 } 1947 1948 /** 1949 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 1950 * for and rollback on error 1951 * @val_up: value passed unmodified to notifier function 1952 * @val_down: value passed unmodified to the notifier function when 1953 * recovering from an error on @val_up 1954 * @info: notifier information data 1955 * 1956 * Call all per-netns network notifier blocks, but not notifier blocks on 1957 * the global notifier chain. Parameters and return value are as for 1958 * raw_notifier_call_chain_robust(). 1959 */ 1960 1961 static int 1962 call_netdevice_notifiers_info_robust(unsigned long val_up, 1963 unsigned long val_down, 1964 struct netdev_notifier_info *info) 1965 { 1966 struct net *net = dev_net(info->dev); 1967 1968 ASSERT_RTNL(); 1969 1970 return raw_notifier_call_chain_robust(&net->netdev_chain, 1971 val_up, val_down, info); 1972 } 1973 1974 static int call_netdevice_notifiers_extack(unsigned long val, 1975 struct net_device *dev, 1976 struct netlink_ext_ack *extack) 1977 { 1978 struct netdev_notifier_info info = { 1979 .dev = dev, 1980 .extack = extack, 1981 }; 1982 1983 return call_netdevice_notifiers_info(val, &info); 1984 } 1985 1986 /** 1987 * call_netdevice_notifiers - call all network notifier blocks 1988 * @val: value passed unmodified to notifier function 1989 * @dev: net_device pointer passed unmodified to notifier function 1990 * 1991 * Call all network notifier blocks. Parameters and return value 1992 * are as for raw_notifier_call_chain(). 1993 */ 1994 1995 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1996 { 1997 return call_netdevice_notifiers_extack(val, dev, NULL); 1998 } 1999 EXPORT_SYMBOL(call_netdevice_notifiers); 2000 2001 /** 2002 * call_netdevice_notifiers_mtu - call all network notifier blocks 2003 * @val: value passed unmodified to notifier function 2004 * @dev: net_device pointer passed unmodified to notifier function 2005 * @arg: additional u32 argument passed to the notifier function 2006 * 2007 * Call all network notifier blocks. Parameters and return value 2008 * are as for raw_notifier_call_chain(). 2009 */ 2010 static int call_netdevice_notifiers_mtu(unsigned long val, 2011 struct net_device *dev, u32 arg) 2012 { 2013 struct netdev_notifier_info_ext info = { 2014 .info.dev = dev, 2015 .ext.mtu = arg, 2016 }; 2017 2018 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2019 2020 return call_netdevice_notifiers_info(val, &info.info); 2021 } 2022 2023 #ifdef CONFIG_NET_INGRESS 2024 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2025 2026 void net_inc_ingress_queue(void) 2027 { 2028 static_branch_inc(&ingress_needed_key); 2029 } 2030 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2031 2032 void net_dec_ingress_queue(void) 2033 { 2034 static_branch_dec(&ingress_needed_key); 2035 } 2036 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2037 #endif 2038 2039 #ifdef CONFIG_NET_EGRESS 2040 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2041 2042 void net_inc_egress_queue(void) 2043 { 2044 static_branch_inc(&egress_needed_key); 2045 } 2046 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2047 2048 void net_dec_egress_queue(void) 2049 { 2050 static_branch_dec(&egress_needed_key); 2051 } 2052 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2053 #endif 2054 2055 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2056 EXPORT_SYMBOL(netstamp_needed_key); 2057 #ifdef CONFIG_JUMP_LABEL 2058 static atomic_t netstamp_needed_deferred; 2059 static atomic_t netstamp_wanted; 2060 static void netstamp_clear(struct work_struct *work) 2061 { 2062 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2063 int wanted; 2064 2065 wanted = atomic_add_return(deferred, &netstamp_wanted); 2066 if (wanted > 0) 2067 static_branch_enable(&netstamp_needed_key); 2068 else 2069 static_branch_disable(&netstamp_needed_key); 2070 } 2071 static DECLARE_WORK(netstamp_work, netstamp_clear); 2072 #endif 2073 2074 void net_enable_timestamp(void) 2075 { 2076 #ifdef CONFIG_JUMP_LABEL 2077 int wanted; 2078 2079 while (1) { 2080 wanted = atomic_read(&netstamp_wanted); 2081 if (wanted <= 0) 2082 break; 2083 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted) 2084 return; 2085 } 2086 atomic_inc(&netstamp_needed_deferred); 2087 schedule_work(&netstamp_work); 2088 #else 2089 static_branch_inc(&netstamp_needed_key); 2090 #endif 2091 } 2092 EXPORT_SYMBOL(net_enable_timestamp); 2093 2094 void net_disable_timestamp(void) 2095 { 2096 #ifdef CONFIG_JUMP_LABEL 2097 int wanted; 2098 2099 while (1) { 2100 wanted = atomic_read(&netstamp_wanted); 2101 if (wanted <= 1) 2102 break; 2103 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted) 2104 return; 2105 } 2106 atomic_dec(&netstamp_needed_deferred); 2107 schedule_work(&netstamp_work); 2108 #else 2109 static_branch_dec(&netstamp_needed_key); 2110 #endif 2111 } 2112 EXPORT_SYMBOL(net_disable_timestamp); 2113 2114 static inline void net_timestamp_set(struct sk_buff *skb) 2115 { 2116 skb->tstamp = 0; 2117 skb->mono_delivery_time = 0; 2118 if (static_branch_unlikely(&netstamp_needed_key)) 2119 skb->tstamp = ktime_get_real(); 2120 } 2121 2122 #define net_timestamp_check(COND, SKB) \ 2123 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2124 if ((COND) && !(SKB)->tstamp) \ 2125 (SKB)->tstamp = ktime_get_real(); \ 2126 } \ 2127 2128 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2129 { 2130 return __is_skb_forwardable(dev, skb, true); 2131 } 2132 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2133 2134 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2135 bool check_mtu) 2136 { 2137 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2138 2139 if (likely(!ret)) { 2140 skb->protocol = eth_type_trans(skb, dev); 2141 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2142 } 2143 2144 return ret; 2145 } 2146 2147 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2148 { 2149 return __dev_forward_skb2(dev, skb, true); 2150 } 2151 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2152 2153 /** 2154 * dev_forward_skb - loopback an skb to another netif 2155 * 2156 * @dev: destination network device 2157 * @skb: buffer to forward 2158 * 2159 * return values: 2160 * NET_RX_SUCCESS (no congestion) 2161 * NET_RX_DROP (packet was dropped, but freed) 2162 * 2163 * dev_forward_skb can be used for injecting an skb from the 2164 * start_xmit function of one device into the receive queue 2165 * of another device. 2166 * 2167 * The receiving device may be in another namespace, so 2168 * we have to clear all information in the skb that could 2169 * impact namespace isolation. 2170 */ 2171 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2172 { 2173 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2174 } 2175 EXPORT_SYMBOL_GPL(dev_forward_skb); 2176 2177 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2178 { 2179 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2180 } 2181 2182 static inline int deliver_skb(struct sk_buff *skb, 2183 struct packet_type *pt_prev, 2184 struct net_device *orig_dev) 2185 { 2186 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2187 return -ENOMEM; 2188 refcount_inc(&skb->users); 2189 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2190 } 2191 2192 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2193 struct packet_type **pt, 2194 struct net_device *orig_dev, 2195 __be16 type, 2196 struct list_head *ptype_list) 2197 { 2198 struct packet_type *ptype, *pt_prev = *pt; 2199 2200 list_for_each_entry_rcu(ptype, ptype_list, list) { 2201 if (ptype->type != type) 2202 continue; 2203 if (pt_prev) 2204 deliver_skb(skb, pt_prev, orig_dev); 2205 pt_prev = ptype; 2206 } 2207 *pt = pt_prev; 2208 } 2209 2210 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2211 { 2212 if (!ptype->af_packet_priv || !skb->sk) 2213 return false; 2214 2215 if (ptype->id_match) 2216 return ptype->id_match(ptype, skb->sk); 2217 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2218 return true; 2219 2220 return false; 2221 } 2222 2223 /** 2224 * dev_nit_active - return true if any network interface taps are in use 2225 * 2226 * @dev: network device to check for the presence of taps 2227 */ 2228 bool dev_nit_active(struct net_device *dev) 2229 { 2230 return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all); 2231 } 2232 EXPORT_SYMBOL_GPL(dev_nit_active); 2233 2234 /* 2235 * Support routine. Sends outgoing frames to any network 2236 * taps currently in use. 2237 */ 2238 2239 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2240 { 2241 struct packet_type *ptype; 2242 struct sk_buff *skb2 = NULL; 2243 struct packet_type *pt_prev = NULL; 2244 struct list_head *ptype_list = &ptype_all; 2245 2246 rcu_read_lock(); 2247 again: 2248 list_for_each_entry_rcu(ptype, ptype_list, list) { 2249 if (ptype->ignore_outgoing) 2250 continue; 2251 2252 /* Never send packets back to the socket 2253 * they originated from - MvS (miquels@drinkel.ow.org) 2254 */ 2255 if (skb_loop_sk(ptype, skb)) 2256 continue; 2257 2258 if (pt_prev) { 2259 deliver_skb(skb2, pt_prev, skb->dev); 2260 pt_prev = ptype; 2261 continue; 2262 } 2263 2264 /* need to clone skb, done only once */ 2265 skb2 = skb_clone(skb, GFP_ATOMIC); 2266 if (!skb2) 2267 goto out_unlock; 2268 2269 net_timestamp_set(skb2); 2270 2271 /* skb->nh should be correctly 2272 * set by sender, so that the second statement is 2273 * just protection against buggy protocols. 2274 */ 2275 skb_reset_mac_header(skb2); 2276 2277 if (skb_network_header(skb2) < skb2->data || 2278 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2279 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2280 ntohs(skb2->protocol), 2281 dev->name); 2282 skb_reset_network_header(skb2); 2283 } 2284 2285 skb2->transport_header = skb2->network_header; 2286 skb2->pkt_type = PACKET_OUTGOING; 2287 pt_prev = ptype; 2288 } 2289 2290 if (ptype_list == &ptype_all) { 2291 ptype_list = &dev->ptype_all; 2292 goto again; 2293 } 2294 out_unlock: 2295 if (pt_prev) { 2296 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2297 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2298 else 2299 kfree_skb(skb2); 2300 } 2301 rcu_read_unlock(); 2302 } 2303 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2304 2305 /** 2306 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2307 * @dev: Network device 2308 * @txq: number of queues available 2309 * 2310 * If real_num_tx_queues is changed the tc mappings may no longer be 2311 * valid. To resolve this verify the tc mapping remains valid and if 2312 * not NULL the mapping. With no priorities mapping to this 2313 * offset/count pair it will no longer be used. In the worst case TC0 2314 * is invalid nothing can be done so disable priority mappings. If is 2315 * expected that drivers will fix this mapping if they can before 2316 * calling netif_set_real_num_tx_queues. 2317 */ 2318 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2319 { 2320 int i; 2321 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2322 2323 /* If TC0 is invalidated disable TC mapping */ 2324 if (tc->offset + tc->count > txq) { 2325 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2326 dev->num_tc = 0; 2327 return; 2328 } 2329 2330 /* Invalidated prio to tc mappings set to TC0 */ 2331 for (i = 1; i < TC_BITMASK + 1; i++) { 2332 int q = netdev_get_prio_tc_map(dev, i); 2333 2334 tc = &dev->tc_to_txq[q]; 2335 if (tc->offset + tc->count > txq) { 2336 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", 2337 i, q); 2338 netdev_set_prio_tc_map(dev, i, 0); 2339 } 2340 } 2341 } 2342 2343 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2344 { 2345 if (dev->num_tc) { 2346 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2347 int i; 2348 2349 /* walk through the TCs and see if it falls into any of them */ 2350 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2351 if ((txq - tc->offset) < tc->count) 2352 return i; 2353 } 2354 2355 /* didn't find it, just return -1 to indicate no match */ 2356 return -1; 2357 } 2358 2359 return 0; 2360 } 2361 EXPORT_SYMBOL(netdev_txq_to_tc); 2362 2363 #ifdef CONFIG_XPS 2364 static struct static_key xps_needed __read_mostly; 2365 static struct static_key xps_rxqs_needed __read_mostly; 2366 static DEFINE_MUTEX(xps_map_mutex); 2367 #define xmap_dereference(P) \ 2368 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2369 2370 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2371 struct xps_dev_maps *old_maps, int tci, u16 index) 2372 { 2373 struct xps_map *map = NULL; 2374 int pos; 2375 2376 if (dev_maps) 2377 map = xmap_dereference(dev_maps->attr_map[tci]); 2378 if (!map) 2379 return false; 2380 2381 for (pos = map->len; pos--;) { 2382 if (map->queues[pos] != index) 2383 continue; 2384 2385 if (map->len > 1) { 2386 map->queues[pos] = map->queues[--map->len]; 2387 break; 2388 } 2389 2390 if (old_maps) 2391 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2392 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2393 kfree_rcu(map, rcu); 2394 return false; 2395 } 2396 2397 return true; 2398 } 2399 2400 static bool remove_xps_queue_cpu(struct net_device *dev, 2401 struct xps_dev_maps *dev_maps, 2402 int cpu, u16 offset, u16 count) 2403 { 2404 int num_tc = dev_maps->num_tc; 2405 bool active = false; 2406 int tci; 2407 2408 for (tci = cpu * num_tc; num_tc--; tci++) { 2409 int i, j; 2410 2411 for (i = count, j = offset; i--; j++) { 2412 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2413 break; 2414 } 2415 2416 active |= i < 0; 2417 } 2418 2419 return active; 2420 } 2421 2422 static void reset_xps_maps(struct net_device *dev, 2423 struct xps_dev_maps *dev_maps, 2424 enum xps_map_type type) 2425 { 2426 static_key_slow_dec_cpuslocked(&xps_needed); 2427 if (type == XPS_RXQS) 2428 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2429 2430 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2431 2432 kfree_rcu(dev_maps, rcu); 2433 } 2434 2435 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2436 u16 offset, u16 count) 2437 { 2438 struct xps_dev_maps *dev_maps; 2439 bool active = false; 2440 int i, j; 2441 2442 dev_maps = xmap_dereference(dev->xps_maps[type]); 2443 if (!dev_maps) 2444 return; 2445 2446 for (j = 0; j < dev_maps->nr_ids; j++) 2447 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2448 if (!active) 2449 reset_xps_maps(dev, dev_maps, type); 2450 2451 if (type == XPS_CPUS) { 2452 for (i = offset + (count - 1); count--; i--) 2453 netdev_queue_numa_node_write( 2454 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2455 } 2456 } 2457 2458 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2459 u16 count) 2460 { 2461 if (!static_key_false(&xps_needed)) 2462 return; 2463 2464 cpus_read_lock(); 2465 mutex_lock(&xps_map_mutex); 2466 2467 if (static_key_false(&xps_rxqs_needed)) 2468 clean_xps_maps(dev, XPS_RXQS, offset, count); 2469 2470 clean_xps_maps(dev, XPS_CPUS, offset, count); 2471 2472 mutex_unlock(&xps_map_mutex); 2473 cpus_read_unlock(); 2474 } 2475 2476 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2477 { 2478 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2479 } 2480 2481 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2482 u16 index, bool is_rxqs_map) 2483 { 2484 struct xps_map *new_map; 2485 int alloc_len = XPS_MIN_MAP_ALLOC; 2486 int i, pos; 2487 2488 for (pos = 0; map && pos < map->len; pos++) { 2489 if (map->queues[pos] != index) 2490 continue; 2491 return map; 2492 } 2493 2494 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2495 if (map) { 2496 if (pos < map->alloc_len) 2497 return map; 2498 2499 alloc_len = map->alloc_len * 2; 2500 } 2501 2502 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2503 * map 2504 */ 2505 if (is_rxqs_map) 2506 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2507 else 2508 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2509 cpu_to_node(attr_index)); 2510 if (!new_map) 2511 return NULL; 2512 2513 for (i = 0; i < pos; i++) 2514 new_map->queues[i] = map->queues[i]; 2515 new_map->alloc_len = alloc_len; 2516 new_map->len = pos; 2517 2518 return new_map; 2519 } 2520 2521 /* Copy xps maps at a given index */ 2522 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2523 struct xps_dev_maps *new_dev_maps, int index, 2524 int tc, bool skip_tc) 2525 { 2526 int i, tci = index * dev_maps->num_tc; 2527 struct xps_map *map; 2528 2529 /* copy maps belonging to foreign traffic classes */ 2530 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2531 if (i == tc && skip_tc) 2532 continue; 2533 2534 /* fill in the new device map from the old device map */ 2535 map = xmap_dereference(dev_maps->attr_map[tci]); 2536 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2537 } 2538 } 2539 2540 /* Must be called under cpus_read_lock */ 2541 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2542 u16 index, enum xps_map_type type) 2543 { 2544 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2545 const unsigned long *online_mask = NULL; 2546 bool active = false, copy = false; 2547 int i, j, tci, numa_node_id = -2; 2548 int maps_sz, num_tc = 1, tc = 0; 2549 struct xps_map *map, *new_map; 2550 unsigned int nr_ids; 2551 2552 if (dev->num_tc) { 2553 /* Do not allow XPS on subordinate device directly */ 2554 num_tc = dev->num_tc; 2555 if (num_tc < 0) 2556 return -EINVAL; 2557 2558 /* If queue belongs to subordinate dev use its map */ 2559 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2560 2561 tc = netdev_txq_to_tc(dev, index); 2562 if (tc < 0) 2563 return -EINVAL; 2564 } 2565 2566 mutex_lock(&xps_map_mutex); 2567 2568 dev_maps = xmap_dereference(dev->xps_maps[type]); 2569 if (type == XPS_RXQS) { 2570 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2571 nr_ids = dev->num_rx_queues; 2572 } else { 2573 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2574 if (num_possible_cpus() > 1) 2575 online_mask = cpumask_bits(cpu_online_mask); 2576 nr_ids = nr_cpu_ids; 2577 } 2578 2579 if (maps_sz < L1_CACHE_BYTES) 2580 maps_sz = L1_CACHE_BYTES; 2581 2582 /* The old dev_maps could be larger or smaller than the one we're 2583 * setting up now, as dev->num_tc or nr_ids could have been updated in 2584 * between. We could try to be smart, but let's be safe instead and only 2585 * copy foreign traffic classes if the two map sizes match. 2586 */ 2587 if (dev_maps && 2588 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2589 copy = true; 2590 2591 /* allocate memory for queue storage */ 2592 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2593 j < nr_ids;) { 2594 if (!new_dev_maps) { 2595 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2596 if (!new_dev_maps) { 2597 mutex_unlock(&xps_map_mutex); 2598 return -ENOMEM; 2599 } 2600 2601 new_dev_maps->nr_ids = nr_ids; 2602 new_dev_maps->num_tc = num_tc; 2603 } 2604 2605 tci = j * num_tc + tc; 2606 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2607 2608 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2609 if (!map) 2610 goto error; 2611 2612 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2613 } 2614 2615 if (!new_dev_maps) 2616 goto out_no_new_maps; 2617 2618 if (!dev_maps) { 2619 /* Increment static keys at most once per type */ 2620 static_key_slow_inc_cpuslocked(&xps_needed); 2621 if (type == XPS_RXQS) 2622 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2623 } 2624 2625 for (j = 0; j < nr_ids; j++) { 2626 bool skip_tc = false; 2627 2628 tci = j * num_tc + tc; 2629 if (netif_attr_test_mask(j, mask, nr_ids) && 2630 netif_attr_test_online(j, online_mask, nr_ids)) { 2631 /* add tx-queue to CPU/rx-queue maps */ 2632 int pos = 0; 2633 2634 skip_tc = true; 2635 2636 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2637 while ((pos < map->len) && (map->queues[pos] != index)) 2638 pos++; 2639 2640 if (pos == map->len) 2641 map->queues[map->len++] = index; 2642 #ifdef CONFIG_NUMA 2643 if (type == XPS_CPUS) { 2644 if (numa_node_id == -2) 2645 numa_node_id = cpu_to_node(j); 2646 else if (numa_node_id != cpu_to_node(j)) 2647 numa_node_id = -1; 2648 } 2649 #endif 2650 } 2651 2652 if (copy) 2653 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2654 skip_tc); 2655 } 2656 2657 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2658 2659 /* Cleanup old maps */ 2660 if (!dev_maps) 2661 goto out_no_old_maps; 2662 2663 for (j = 0; j < dev_maps->nr_ids; j++) { 2664 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2665 map = xmap_dereference(dev_maps->attr_map[tci]); 2666 if (!map) 2667 continue; 2668 2669 if (copy) { 2670 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2671 if (map == new_map) 2672 continue; 2673 } 2674 2675 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2676 kfree_rcu(map, rcu); 2677 } 2678 } 2679 2680 old_dev_maps = dev_maps; 2681 2682 out_no_old_maps: 2683 dev_maps = new_dev_maps; 2684 active = true; 2685 2686 out_no_new_maps: 2687 if (type == XPS_CPUS) 2688 /* update Tx queue numa node */ 2689 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2690 (numa_node_id >= 0) ? 2691 numa_node_id : NUMA_NO_NODE); 2692 2693 if (!dev_maps) 2694 goto out_no_maps; 2695 2696 /* removes tx-queue from unused CPUs/rx-queues */ 2697 for (j = 0; j < dev_maps->nr_ids; j++) { 2698 tci = j * dev_maps->num_tc; 2699 2700 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2701 if (i == tc && 2702 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2703 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2704 continue; 2705 2706 active |= remove_xps_queue(dev_maps, 2707 copy ? old_dev_maps : NULL, 2708 tci, index); 2709 } 2710 } 2711 2712 if (old_dev_maps) 2713 kfree_rcu(old_dev_maps, rcu); 2714 2715 /* free map if not active */ 2716 if (!active) 2717 reset_xps_maps(dev, dev_maps, type); 2718 2719 out_no_maps: 2720 mutex_unlock(&xps_map_mutex); 2721 2722 return 0; 2723 error: 2724 /* remove any maps that we added */ 2725 for (j = 0; j < nr_ids; j++) { 2726 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2727 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2728 map = copy ? 2729 xmap_dereference(dev_maps->attr_map[tci]) : 2730 NULL; 2731 if (new_map && new_map != map) 2732 kfree(new_map); 2733 } 2734 } 2735 2736 mutex_unlock(&xps_map_mutex); 2737 2738 kfree(new_dev_maps); 2739 return -ENOMEM; 2740 } 2741 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2742 2743 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2744 u16 index) 2745 { 2746 int ret; 2747 2748 cpus_read_lock(); 2749 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2750 cpus_read_unlock(); 2751 2752 return ret; 2753 } 2754 EXPORT_SYMBOL(netif_set_xps_queue); 2755 2756 #endif 2757 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2758 { 2759 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2760 2761 /* Unbind any subordinate channels */ 2762 while (txq-- != &dev->_tx[0]) { 2763 if (txq->sb_dev) 2764 netdev_unbind_sb_channel(dev, txq->sb_dev); 2765 } 2766 } 2767 2768 void netdev_reset_tc(struct net_device *dev) 2769 { 2770 #ifdef CONFIG_XPS 2771 netif_reset_xps_queues_gt(dev, 0); 2772 #endif 2773 netdev_unbind_all_sb_channels(dev); 2774 2775 /* Reset TC configuration of device */ 2776 dev->num_tc = 0; 2777 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2778 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2779 } 2780 EXPORT_SYMBOL(netdev_reset_tc); 2781 2782 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2783 { 2784 if (tc >= dev->num_tc) 2785 return -EINVAL; 2786 2787 #ifdef CONFIG_XPS 2788 netif_reset_xps_queues(dev, offset, count); 2789 #endif 2790 dev->tc_to_txq[tc].count = count; 2791 dev->tc_to_txq[tc].offset = offset; 2792 return 0; 2793 } 2794 EXPORT_SYMBOL(netdev_set_tc_queue); 2795 2796 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2797 { 2798 if (num_tc > TC_MAX_QUEUE) 2799 return -EINVAL; 2800 2801 #ifdef CONFIG_XPS 2802 netif_reset_xps_queues_gt(dev, 0); 2803 #endif 2804 netdev_unbind_all_sb_channels(dev); 2805 2806 dev->num_tc = num_tc; 2807 return 0; 2808 } 2809 EXPORT_SYMBOL(netdev_set_num_tc); 2810 2811 void netdev_unbind_sb_channel(struct net_device *dev, 2812 struct net_device *sb_dev) 2813 { 2814 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2815 2816 #ifdef CONFIG_XPS 2817 netif_reset_xps_queues_gt(sb_dev, 0); 2818 #endif 2819 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2820 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2821 2822 while (txq-- != &dev->_tx[0]) { 2823 if (txq->sb_dev == sb_dev) 2824 txq->sb_dev = NULL; 2825 } 2826 } 2827 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2828 2829 int netdev_bind_sb_channel_queue(struct net_device *dev, 2830 struct net_device *sb_dev, 2831 u8 tc, u16 count, u16 offset) 2832 { 2833 /* Make certain the sb_dev and dev are already configured */ 2834 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2835 return -EINVAL; 2836 2837 /* We cannot hand out queues we don't have */ 2838 if ((offset + count) > dev->real_num_tx_queues) 2839 return -EINVAL; 2840 2841 /* Record the mapping */ 2842 sb_dev->tc_to_txq[tc].count = count; 2843 sb_dev->tc_to_txq[tc].offset = offset; 2844 2845 /* Provide a way for Tx queue to find the tc_to_txq map or 2846 * XPS map for itself. 2847 */ 2848 while (count--) 2849 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2850 2851 return 0; 2852 } 2853 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2854 2855 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2856 { 2857 /* Do not use a multiqueue device to represent a subordinate channel */ 2858 if (netif_is_multiqueue(dev)) 2859 return -ENODEV; 2860 2861 /* We allow channels 1 - 32767 to be used for subordinate channels. 2862 * Channel 0 is meant to be "native" mode and used only to represent 2863 * the main root device. We allow writing 0 to reset the device back 2864 * to normal mode after being used as a subordinate channel. 2865 */ 2866 if (channel > S16_MAX) 2867 return -EINVAL; 2868 2869 dev->num_tc = -channel; 2870 2871 return 0; 2872 } 2873 EXPORT_SYMBOL(netdev_set_sb_channel); 2874 2875 /* 2876 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2877 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2878 */ 2879 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2880 { 2881 bool disabling; 2882 int rc; 2883 2884 disabling = txq < dev->real_num_tx_queues; 2885 2886 if (txq < 1 || txq > dev->num_tx_queues) 2887 return -EINVAL; 2888 2889 if (dev->reg_state == NETREG_REGISTERED || 2890 dev->reg_state == NETREG_UNREGISTERING) { 2891 ASSERT_RTNL(); 2892 2893 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2894 txq); 2895 if (rc) 2896 return rc; 2897 2898 if (dev->num_tc) 2899 netif_setup_tc(dev, txq); 2900 2901 dev_qdisc_change_real_num_tx(dev, txq); 2902 2903 dev->real_num_tx_queues = txq; 2904 2905 if (disabling) { 2906 synchronize_net(); 2907 qdisc_reset_all_tx_gt(dev, txq); 2908 #ifdef CONFIG_XPS 2909 netif_reset_xps_queues_gt(dev, txq); 2910 #endif 2911 } 2912 } else { 2913 dev->real_num_tx_queues = txq; 2914 } 2915 2916 return 0; 2917 } 2918 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2919 2920 #ifdef CONFIG_SYSFS 2921 /** 2922 * netif_set_real_num_rx_queues - set actual number of RX queues used 2923 * @dev: Network device 2924 * @rxq: Actual number of RX queues 2925 * 2926 * This must be called either with the rtnl_lock held or before 2927 * registration of the net device. Returns 0 on success, or a 2928 * negative error code. If called before registration, it always 2929 * succeeds. 2930 */ 2931 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2932 { 2933 int rc; 2934 2935 if (rxq < 1 || rxq > dev->num_rx_queues) 2936 return -EINVAL; 2937 2938 if (dev->reg_state == NETREG_REGISTERED) { 2939 ASSERT_RTNL(); 2940 2941 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2942 rxq); 2943 if (rc) 2944 return rc; 2945 } 2946 2947 dev->real_num_rx_queues = rxq; 2948 return 0; 2949 } 2950 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2951 #endif 2952 2953 /** 2954 * netif_set_real_num_queues - set actual number of RX and TX queues used 2955 * @dev: Network device 2956 * @txq: Actual number of TX queues 2957 * @rxq: Actual number of RX queues 2958 * 2959 * Set the real number of both TX and RX queues. 2960 * Does nothing if the number of queues is already correct. 2961 */ 2962 int netif_set_real_num_queues(struct net_device *dev, 2963 unsigned int txq, unsigned int rxq) 2964 { 2965 unsigned int old_rxq = dev->real_num_rx_queues; 2966 int err; 2967 2968 if (txq < 1 || txq > dev->num_tx_queues || 2969 rxq < 1 || rxq > dev->num_rx_queues) 2970 return -EINVAL; 2971 2972 /* Start from increases, so the error path only does decreases - 2973 * decreases can't fail. 2974 */ 2975 if (rxq > dev->real_num_rx_queues) { 2976 err = netif_set_real_num_rx_queues(dev, rxq); 2977 if (err) 2978 return err; 2979 } 2980 if (txq > dev->real_num_tx_queues) { 2981 err = netif_set_real_num_tx_queues(dev, txq); 2982 if (err) 2983 goto undo_rx; 2984 } 2985 if (rxq < dev->real_num_rx_queues) 2986 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 2987 if (txq < dev->real_num_tx_queues) 2988 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 2989 2990 return 0; 2991 undo_rx: 2992 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 2993 return err; 2994 } 2995 EXPORT_SYMBOL(netif_set_real_num_queues); 2996 2997 /** 2998 * netif_set_tso_max_size() - set the max size of TSO frames supported 2999 * @dev: netdev to update 3000 * @size: max skb->len of a TSO frame 3001 * 3002 * Set the limit on the size of TSO super-frames the device can handle. 3003 * Unless explicitly set the stack will assume the value of 3004 * %GSO_LEGACY_MAX_SIZE. 3005 */ 3006 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3007 { 3008 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3009 if (size < READ_ONCE(dev->gso_max_size)) 3010 netif_set_gso_max_size(dev, size); 3011 } 3012 EXPORT_SYMBOL(netif_set_tso_max_size); 3013 3014 /** 3015 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3016 * @dev: netdev to update 3017 * @segs: max number of TCP segments 3018 * 3019 * Set the limit on the number of TCP segments the device can generate from 3020 * a single TSO super-frame. 3021 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3022 */ 3023 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3024 { 3025 dev->tso_max_segs = segs; 3026 if (segs < READ_ONCE(dev->gso_max_segs)) 3027 netif_set_gso_max_segs(dev, segs); 3028 } 3029 EXPORT_SYMBOL(netif_set_tso_max_segs); 3030 3031 /** 3032 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3033 * @to: netdev to update 3034 * @from: netdev from which to copy the limits 3035 */ 3036 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3037 { 3038 netif_set_tso_max_size(to, from->tso_max_size); 3039 netif_set_tso_max_segs(to, from->tso_max_segs); 3040 } 3041 EXPORT_SYMBOL(netif_inherit_tso_max); 3042 3043 /** 3044 * netif_get_num_default_rss_queues - default number of RSS queues 3045 * 3046 * Default value is the number of physical cores if there are only 1 or 2, or 3047 * divided by 2 if there are more. 3048 */ 3049 int netif_get_num_default_rss_queues(void) 3050 { 3051 cpumask_var_t cpus; 3052 int cpu, count = 0; 3053 3054 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3055 return 1; 3056 3057 cpumask_copy(cpus, cpu_online_mask); 3058 for_each_cpu(cpu, cpus) { 3059 ++count; 3060 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3061 } 3062 free_cpumask_var(cpus); 3063 3064 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3065 } 3066 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3067 3068 static void __netif_reschedule(struct Qdisc *q) 3069 { 3070 struct softnet_data *sd; 3071 unsigned long flags; 3072 3073 local_irq_save(flags); 3074 sd = this_cpu_ptr(&softnet_data); 3075 q->next_sched = NULL; 3076 *sd->output_queue_tailp = q; 3077 sd->output_queue_tailp = &q->next_sched; 3078 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3079 local_irq_restore(flags); 3080 } 3081 3082 void __netif_schedule(struct Qdisc *q) 3083 { 3084 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3085 __netif_reschedule(q); 3086 } 3087 EXPORT_SYMBOL(__netif_schedule); 3088 3089 struct dev_kfree_skb_cb { 3090 enum skb_free_reason reason; 3091 }; 3092 3093 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3094 { 3095 return (struct dev_kfree_skb_cb *)skb->cb; 3096 } 3097 3098 void netif_schedule_queue(struct netdev_queue *txq) 3099 { 3100 rcu_read_lock(); 3101 if (!netif_xmit_stopped(txq)) { 3102 struct Qdisc *q = rcu_dereference(txq->qdisc); 3103 3104 __netif_schedule(q); 3105 } 3106 rcu_read_unlock(); 3107 } 3108 EXPORT_SYMBOL(netif_schedule_queue); 3109 3110 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3111 { 3112 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3113 struct Qdisc *q; 3114 3115 rcu_read_lock(); 3116 q = rcu_dereference(dev_queue->qdisc); 3117 __netif_schedule(q); 3118 rcu_read_unlock(); 3119 } 3120 } 3121 EXPORT_SYMBOL(netif_tx_wake_queue); 3122 3123 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) 3124 { 3125 unsigned long flags; 3126 3127 if (unlikely(!skb)) 3128 return; 3129 3130 if (likely(refcount_read(&skb->users) == 1)) { 3131 smp_rmb(); 3132 refcount_set(&skb->users, 0); 3133 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3134 return; 3135 } 3136 get_kfree_skb_cb(skb)->reason = reason; 3137 local_irq_save(flags); 3138 skb->next = __this_cpu_read(softnet_data.completion_queue); 3139 __this_cpu_write(softnet_data.completion_queue, skb); 3140 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3141 local_irq_restore(flags); 3142 } 3143 EXPORT_SYMBOL(__dev_kfree_skb_irq); 3144 3145 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason) 3146 { 3147 if (in_hardirq() || irqs_disabled()) 3148 __dev_kfree_skb_irq(skb, reason); 3149 else 3150 dev_kfree_skb(skb); 3151 } 3152 EXPORT_SYMBOL(__dev_kfree_skb_any); 3153 3154 3155 /** 3156 * netif_device_detach - mark device as removed 3157 * @dev: network device 3158 * 3159 * Mark device as removed from system and therefore no longer available. 3160 */ 3161 void netif_device_detach(struct net_device *dev) 3162 { 3163 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3164 netif_running(dev)) { 3165 netif_tx_stop_all_queues(dev); 3166 } 3167 } 3168 EXPORT_SYMBOL(netif_device_detach); 3169 3170 /** 3171 * netif_device_attach - mark device as attached 3172 * @dev: network device 3173 * 3174 * Mark device as attached from system and restart if needed. 3175 */ 3176 void netif_device_attach(struct net_device *dev) 3177 { 3178 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3179 netif_running(dev)) { 3180 netif_tx_wake_all_queues(dev); 3181 __netdev_watchdog_up(dev); 3182 } 3183 } 3184 EXPORT_SYMBOL(netif_device_attach); 3185 3186 /* 3187 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3188 * to be used as a distribution range. 3189 */ 3190 static u16 skb_tx_hash(const struct net_device *dev, 3191 const struct net_device *sb_dev, 3192 struct sk_buff *skb) 3193 { 3194 u32 hash; 3195 u16 qoffset = 0; 3196 u16 qcount = dev->real_num_tx_queues; 3197 3198 if (dev->num_tc) { 3199 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3200 3201 qoffset = sb_dev->tc_to_txq[tc].offset; 3202 qcount = sb_dev->tc_to_txq[tc].count; 3203 if (unlikely(!qcount)) { 3204 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3205 sb_dev->name, qoffset, tc); 3206 qoffset = 0; 3207 qcount = dev->real_num_tx_queues; 3208 } 3209 } 3210 3211 if (skb_rx_queue_recorded(skb)) { 3212 hash = skb_get_rx_queue(skb); 3213 if (hash >= qoffset) 3214 hash -= qoffset; 3215 while (unlikely(hash >= qcount)) 3216 hash -= qcount; 3217 return hash + qoffset; 3218 } 3219 3220 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3221 } 3222 3223 static void skb_warn_bad_offload(const struct sk_buff *skb) 3224 { 3225 static const netdev_features_t null_features; 3226 struct net_device *dev = skb->dev; 3227 const char *name = ""; 3228 3229 if (!net_ratelimit()) 3230 return; 3231 3232 if (dev) { 3233 if (dev->dev.parent) 3234 name = dev_driver_string(dev->dev.parent); 3235 else 3236 name = netdev_name(dev); 3237 } 3238 skb_dump(KERN_WARNING, skb, false); 3239 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3240 name, dev ? &dev->features : &null_features, 3241 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3242 } 3243 3244 /* 3245 * Invalidate hardware checksum when packet is to be mangled, and 3246 * complete checksum manually on outgoing path. 3247 */ 3248 int skb_checksum_help(struct sk_buff *skb) 3249 { 3250 __wsum csum; 3251 int ret = 0, offset; 3252 3253 if (skb->ip_summed == CHECKSUM_COMPLETE) 3254 goto out_set_summed; 3255 3256 if (unlikely(skb_is_gso(skb))) { 3257 skb_warn_bad_offload(skb); 3258 return -EINVAL; 3259 } 3260 3261 /* Before computing a checksum, we should make sure no frag could 3262 * be modified by an external entity : checksum could be wrong. 3263 */ 3264 if (skb_has_shared_frag(skb)) { 3265 ret = __skb_linearize(skb); 3266 if (ret) 3267 goto out; 3268 } 3269 3270 offset = skb_checksum_start_offset(skb); 3271 ret = -EINVAL; 3272 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3273 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3274 goto out; 3275 } 3276 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3277 3278 offset += skb->csum_offset; 3279 if (WARN_ON_ONCE(offset + sizeof(__sum16) > skb_headlen(skb))) { 3280 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3281 goto out; 3282 } 3283 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3284 if (ret) 3285 goto out; 3286 3287 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3288 out_set_summed: 3289 skb->ip_summed = CHECKSUM_NONE; 3290 out: 3291 return ret; 3292 } 3293 EXPORT_SYMBOL(skb_checksum_help); 3294 3295 int skb_crc32c_csum_help(struct sk_buff *skb) 3296 { 3297 __le32 crc32c_csum; 3298 int ret = 0, offset, start; 3299 3300 if (skb->ip_summed != CHECKSUM_PARTIAL) 3301 goto out; 3302 3303 if (unlikely(skb_is_gso(skb))) 3304 goto out; 3305 3306 /* Before computing a checksum, we should make sure no frag could 3307 * be modified by an external entity : checksum could be wrong. 3308 */ 3309 if (unlikely(skb_has_shared_frag(skb))) { 3310 ret = __skb_linearize(skb); 3311 if (ret) 3312 goto out; 3313 } 3314 start = skb_checksum_start_offset(skb); 3315 offset = start + offsetof(struct sctphdr, checksum); 3316 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3317 ret = -EINVAL; 3318 goto out; 3319 } 3320 3321 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3322 if (ret) 3323 goto out; 3324 3325 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3326 skb->len - start, ~(__u32)0, 3327 crc32c_csum_stub)); 3328 *(__le32 *)(skb->data + offset) = crc32c_csum; 3329 skb->ip_summed = CHECKSUM_NONE; 3330 skb->csum_not_inet = 0; 3331 out: 3332 return ret; 3333 } 3334 3335 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3336 { 3337 __be16 type = skb->protocol; 3338 3339 /* Tunnel gso handlers can set protocol to ethernet. */ 3340 if (type == htons(ETH_P_TEB)) { 3341 struct ethhdr *eth; 3342 3343 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3344 return 0; 3345 3346 eth = (struct ethhdr *)skb->data; 3347 type = eth->h_proto; 3348 } 3349 3350 return __vlan_get_protocol(skb, type, depth); 3351 } 3352 3353 /* openvswitch calls this on rx path, so we need a different check. 3354 */ 3355 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) 3356 { 3357 if (tx_path) 3358 return skb->ip_summed != CHECKSUM_PARTIAL && 3359 skb->ip_summed != CHECKSUM_UNNECESSARY; 3360 3361 return skb->ip_summed == CHECKSUM_NONE; 3362 } 3363 3364 /** 3365 * __skb_gso_segment - Perform segmentation on skb. 3366 * @skb: buffer to segment 3367 * @features: features for the output path (see dev->features) 3368 * @tx_path: whether it is called in TX path 3369 * 3370 * This function segments the given skb and returns a list of segments. 3371 * 3372 * It may return NULL if the skb requires no segmentation. This is 3373 * only possible when GSO is used for verifying header integrity. 3374 * 3375 * Segmentation preserves SKB_GSO_CB_OFFSET bytes of previous skb cb. 3376 */ 3377 struct sk_buff *__skb_gso_segment(struct sk_buff *skb, 3378 netdev_features_t features, bool tx_path) 3379 { 3380 struct sk_buff *segs; 3381 3382 if (unlikely(skb_needs_check(skb, tx_path))) { 3383 int err; 3384 3385 /* We're going to init ->check field in TCP or UDP header */ 3386 err = skb_cow_head(skb, 0); 3387 if (err < 0) 3388 return ERR_PTR(err); 3389 } 3390 3391 /* Only report GSO partial support if it will enable us to 3392 * support segmentation on this frame without needing additional 3393 * work. 3394 */ 3395 if (features & NETIF_F_GSO_PARTIAL) { 3396 netdev_features_t partial_features = NETIF_F_GSO_ROBUST; 3397 struct net_device *dev = skb->dev; 3398 3399 partial_features |= dev->features & dev->gso_partial_features; 3400 if (!skb_gso_ok(skb, features | partial_features)) 3401 features &= ~NETIF_F_GSO_PARTIAL; 3402 } 3403 3404 BUILD_BUG_ON(SKB_GSO_CB_OFFSET + 3405 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); 3406 3407 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); 3408 SKB_GSO_CB(skb)->encap_level = 0; 3409 3410 skb_reset_mac_header(skb); 3411 skb_reset_mac_len(skb); 3412 3413 segs = skb_mac_gso_segment(skb, features); 3414 3415 if (segs != skb && unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs))) 3416 skb_warn_bad_offload(skb); 3417 3418 return segs; 3419 } 3420 EXPORT_SYMBOL(__skb_gso_segment); 3421 3422 /* Take action when hardware reception checksum errors are detected. */ 3423 #ifdef CONFIG_BUG 3424 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3425 { 3426 netdev_err(dev, "hw csum failure\n"); 3427 skb_dump(KERN_ERR, skb, true); 3428 dump_stack(); 3429 } 3430 3431 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3432 { 3433 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3434 } 3435 EXPORT_SYMBOL(netdev_rx_csum_fault); 3436 #endif 3437 3438 /* XXX: check that highmem exists at all on the given machine. */ 3439 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3440 { 3441 #ifdef CONFIG_HIGHMEM 3442 int i; 3443 3444 if (!(dev->features & NETIF_F_HIGHDMA)) { 3445 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3446 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3447 3448 if (PageHighMem(skb_frag_page(frag))) 3449 return 1; 3450 } 3451 } 3452 #endif 3453 return 0; 3454 } 3455 3456 /* If MPLS offload request, verify we are testing hardware MPLS features 3457 * instead of standard features for the netdev. 3458 */ 3459 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3460 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3461 netdev_features_t features, 3462 __be16 type) 3463 { 3464 if (eth_p_mpls(type)) 3465 features &= skb->dev->mpls_features; 3466 3467 return features; 3468 } 3469 #else 3470 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3471 netdev_features_t features, 3472 __be16 type) 3473 { 3474 return features; 3475 } 3476 #endif 3477 3478 static netdev_features_t harmonize_features(struct sk_buff *skb, 3479 netdev_features_t features) 3480 { 3481 __be16 type; 3482 3483 type = skb_network_protocol(skb, NULL); 3484 features = net_mpls_features(skb, features, type); 3485 3486 if (skb->ip_summed != CHECKSUM_NONE && 3487 !can_checksum_protocol(features, type)) { 3488 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3489 } 3490 if (illegal_highdma(skb->dev, skb)) 3491 features &= ~NETIF_F_SG; 3492 3493 return features; 3494 } 3495 3496 netdev_features_t passthru_features_check(struct sk_buff *skb, 3497 struct net_device *dev, 3498 netdev_features_t features) 3499 { 3500 return features; 3501 } 3502 EXPORT_SYMBOL(passthru_features_check); 3503 3504 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3505 struct net_device *dev, 3506 netdev_features_t features) 3507 { 3508 return vlan_features_check(skb, features); 3509 } 3510 3511 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3512 struct net_device *dev, 3513 netdev_features_t features) 3514 { 3515 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3516 3517 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3518 return features & ~NETIF_F_GSO_MASK; 3519 3520 if (!skb_shinfo(skb)->gso_type) { 3521 skb_warn_bad_offload(skb); 3522 return features & ~NETIF_F_GSO_MASK; 3523 } 3524 3525 /* Support for GSO partial features requires software 3526 * intervention before we can actually process the packets 3527 * so we need to strip support for any partial features now 3528 * and we can pull them back in after we have partially 3529 * segmented the frame. 3530 */ 3531 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3532 features &= ~dev->gso_partial_features; 3533 3534 /* Make sure to clear the IPv4 ID mangling feature if the 3535 * IPv4 header has the potential to be fragmented. 3536 */ 3537 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3538 struct iphdr *iph = skb->encapsulation ? 3539 inner_ip_hdr(skb) : ip_hdr(skb); 3540 3541 if (!(iph->frag_off & htons(IP_DF))) 3542 features &= ~NETIF_F_TSO_MANGLEID; 3543 } 3544 3545 return features; 3546 } 3547 3548 netdev_features_t netif_skb_features(struct sk_buff *skb) 3549 { 3550 struct net_device *dev = skb->dev; 3551 netdev_features_t features = dev->features; 3552 3553 if (skb_is_gso(skb)) 3554 features = gso_features_check(skb, dev, features); 3555 3556 /* If encapsulation offload request, verify we are testing 3557 * hardware encapsulation features instead of standard 3558 * features for the netdev 3559 */ 3560 if (skb->encapsulation) 3561 features &= dev->hw_enc_features; 3562 3563 if (skb_vlan_tagged(skb)) 3564 features = netdev_intersect_features(features, 3565 dev->vlan_features | 3566 NETIF_F_HW_VLAN_CTAG_TX | 3567 NETIF_F_HW_VLAN_STAG_TX); 3568 3569 if (dev->netdev_ops->ndo_features_check) 3570 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3571 features); 3572 else 3573 features &= dflt_features_check(skb, dev, features); 3574 3575 return harmonize_features(skb, features); 3576 } 3577 EXPORT_SYMBOL(netif_skb_features); 3578 3579 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3580 struct netdev_queue *txq, bool more) 3581 { 3582 unsigned int len; 3583 int rc; 3584 3585 if (dev_nit_active(dev)) 3586 dev_queue_xmit_nit(skb, dev); 3587 3588 len = skb->len; 3589 trace_net_dev_start_xmit(skb, dev); 3590 rc = netdev_start_xmit(skb, dev, txq, more); 3591 trace_net_dev_xmit(skb, rc, dev, len); 3592 3593 return rc; 3594 } 3595 3596 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3597 struct netdev_queue *txq, int *ret) 3598 { 3599 struct sk_buff *skb = first; 3600 int rc = NETDEV_TX_OK; 3601 3602 while (skb) { 3603 struct sk_buff *next = skb->next; 3604 3605 skb_mark_not_on_list(skb); 3606 rc = xmit_one(skb, dev, txq, next != NULL); 3607 if (unlikely(!dev_xmit_complete(rc))) { 3608 skb->next = next; 3609 goto out; 3610 } 3611 3612 skb = next; 3613 if (netif_tx_queue_stopped(txq) && skb) { 3614 rc = NETDEV_TX_BUSY; 3615 break; 3616 } 3617 } 3618 3619 out: 3620 *ret = rc; 3621 return skb; 3622 } 3623 3624 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3625 netdev_features_t features) 3626 { 3627 if (skb_vlan_tag_present(skb) && 3628 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3629 skb = __vlan_hwaccel_push_inside(skb); 3630 return skb; 3631 } 3632 3633 int skb_csum_hwoffload_help(struct sk_buff *skb, 3634 const netdev_features_t features) 3635 { 3636 if (unlikely(skb_csum_is_sctp(skb))) 3637 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3638 skb_crc32c_csum_help(skb); 3639 3640 if (features & NETIF_F_HW_CSUM) 3641 return 0; 3642 3643 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3644 switch (skb->csum_offset) { 3645 case offsetof(struct tcphdr, check): 3646 case offsetof(struct udphdr, check): 3647 return 0; 3648 } 3649 } 3650 3651 return skb_checksum_help(skb); 3652 } 3653 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3654 3655 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3656 { 3657 netdev_features_t features; 3658 3659 features = netif_skb_features(skb); 3660 skb = validate_xmit_vlan(skb, features); 3661 if (unlikely(!skb)) 3662 goto out_null; 3663 3664 skb = sk_validate_xmit_skb(skb, dev); 3665 if (unlikely(!skb)) 3666 goto out_null; 3667 3668 if (netif_needs_gso(skb, features)) { 3669 struct sk_buff *segs; 3670 3671 segs = skb_gso_segment(skb, features); 3672 if (IS_ERR(segs)) { 3673 goto out_kfree_skb; 3674 } else if (segs) { 3675 consume_skb(skb); 3676 skb = segs; 3677 } 3678 } else { 3679 if (skb_needs_linearize(skb, features) && 3680 __skb_linearize(skb)) 3681 goto out_kfree_skb; 3682 3683 /* If packet is not checksummed and device does not 3684 * support checksumming for this protocol, complete 3685 * checksumming here. 3686 */ 3687 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3688 if (skb->encapsulation) 3689 skb_set_inner_transport_header(skb, 3690 skb_checksum_start_offset(skb)); 3691 else 3692 skb_set_transport_header(skb, 3693 skb_checksum_start_offset(skb)); 3694 if (skb_csum_hwoffload_help(skb, features)) 3695 goto out_kfree_skb; 3696 } 3697 } 3698 3699 skb = validate_xmit_xfrm(skb, features, again); 3700 3701 return skb; 3702 3703 out_kfree_skb: 3704 kfree_skb(skb); 3705 out_null: 3706 dev_core_stats_tx_dropped_inc(dev); 3707 return NULL; 3708 } 3709 3710 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3711 { 3712 struct sk_buff *next, *head = NULL, *tail; 3713 3714 for (; skb != NULL; skb = next) { 3715 next = skb->next; 3716 skb_mark_not_on_list(skb); 3717 3718 /* in case skb wont be segmented, point to itself */ 3719 skb->prev = skb; 3720 3721 skb = validate_xmit_skb(skb, dev, again); 3722 if (!skb) 3723 continue; 3724 3725 if (!head) 3726 head = skb; 3727 else 3728 tail->next = skb; 3729 /* If skb was segmented, skb->prev points to 3730 * the last segment. If not, it still contains skb. 3731 */ 3732 tail = skb->prev; 3733 } 3734 return head; 3735 } 3736 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3737 3738 static void qdisc_pkt_len_init(struct sk_buff *skb) 3739 { 3740 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3741 3742 qdisc_skb_cb(skb)->pkt_len = skb->len; 3743 3744 /* To get more precise estimation of bytes sent on wire, 3745 * we add to pkt_len the headers size of all segments 3746 */ 3747 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3748 unsigned int hdr_len; 3749 u16 gso_segs = shinfo->gso_segs; 3750 3751 /* mac layer + network layer */ 3752 hdr_len = skb_transport_header(skb) - skb_mac_header(skb); 3753 3754 /* + transport layer */ 3755 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3756 const struct tcphdr *th; 3757 struct tcphdr _tcphdr; 3758 3759 th = skb_header_pointer(skb, skb_transport_offset(skb), 3760 sizeof(_tcphdr), &_tcphdr); 3761 if (likely(th)) 3762 hdr_len += __tcp_hdrlen(th); 3763 } else { 3764 struct udphdr _udphdr; 3765 3766 if (skb_header_pointer(skb, skb_transport_offset(skb), 3767 sizeof(_udphdr), &_udphdr)) 3768 hdr_len += sizeof(struct udphdr); 3769 } 3770 3771 if (shinfo->gso_type & SKB_GSO_DODGY) 3772 gso_segs = DIV_ROUND_UP(skb->len - hdr_len, 3773 shinfo->gso_size); 3774 3775 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3776 } 3777 } 3778 3779 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3780 struct sk_buff **to_free, 3781 struct netdev_queue *txq) 3782 { 3783 int rc; 3784 3785 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3786 if (rc == NET_XMIT_SUCCESS) 3787 trace_qdisc_enqueue(q, txq, skb); 3788 return rc; 3789 } 3790 3791 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3792 struct net_device *dev, 3793 struct netdev_queue *txq) 3794 { 3795 spinlock_t *root_lock = qdisc_lock(q); 3796 struct sk_buff *to_free = NULL; 3797 bool contended; 3798 int rc; 3799 3800 qdisc_calculate_pkt_len(skb, q); 3801 3802 if (q->flags & TCQ_F_NOLOCK) { 3803 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3804 qdisc_run_begin(q)) { 3805 /* Retest nolock_qdisc_is_empty() within the protection 3806 * of q->seqlock to protect from racing with requeuing. 3807 */ 3808 if (unlikely(!nolock_qdisc_is_empty(q))) { 3809 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3810 __qdisc_run(q); 3811 qdisc_run_end(q); 3812 3813 goto no_lock_out; 3814 } 3815 3816 qdisc_bstats_cpu_update(q, skb); 3817 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3818 !nolock_qdisc_is_empty(q)) 3819 __qdisc_run(q); 3820 3821 qdisc_run_end(q); 3822 return NET_XMIT_SUCCESS; 3823 } 3824 3825 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3826 qdisc_run(q); 3827 3828 no_lock_out: 3829 if (unlikely(to_free)) 3830 kfree_skb_list_reason(to_free, 3831 SKB_DROP_REASON_QDISC_DROP); 3832 return rc; 3833 } 3834 3835 /* 3836 * Heuristic to force contended enqueues to serialize on a 3837 * separate lock before trying to get qdisc main lock. 3838 * This permits qdisc->running owner to get the lock more 3839 * often and dequeue packets faster. 3840 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 3841 * and then other tasks will only enqueue packets. The packets will be 3842 * sent after the qdisc owner is scheduled again. To prevent this 3843 * scenario the task always serialize on the lock. 3844 */ 3845 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 3846 if (unlikely(contended)) 3847 spin_lock(&q->busylock); 3848 3849 spin_lock(root_lock); 3850 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3851 __qdisc_drop(skb, &to_free); 3852 rc = NET_XMIT_DROP; 3853 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3854 qdisc_run_begin(q)) { 3855 /* 3856 * This is a work-conserving queue; there are no old skbs 3857 * waiting to be sent out; and the qdisc is not running - 3858 * xmit the skb directly. 3859 */ 3860 3861 qdisc_bstats_update(q, skb); 3862 3863 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3864 if (unlikely(contended)) { 3865 spin_unlock(&q->busylock); 3866 contended = false; 3867 } 3868 __qdisc_run(q); 3869 } 3870 3871 qdisc_run_end(q); 3872 rc = NET_XMIT_SUCCESS; 3873 } else { 3874 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3875 if (qdisc_run_begin(q)) { 3876 if (unlikely(contended)) { 3877 spin_unlock(&q->busylock); 3878 contended = false; 3879 } 3880 __qdisc_run(q); 3881 qdisc_run_end(q); 3882 } 3883 } 3884 spin_unlock(root_lock); 3885 if (unlikely(to_free)) 3886 kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP); 3887 if (unlikely(contended)) 3888 spin_unlock(&q->busylock); 3889 return rc; 3890 } 3891 3892 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3893 static void skb_update_prio(struct sk_buff *skb) 3894 { 3895 const struct netprio_map *map; 3896 const struct sock *sk; 3897 unsigned int prioidx; 3898 3899 if (skb->priority) 3900 return; 3901 map = rcu_dereference_bh(skb->dev->priomap); 3902 if (!map) 3903 return; 3904 sk = skb_to_full_sk(skb); 3905 if (!sk) 3906 return; 3907 3908 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3909 3910 if (prioidx < map->priomap_len) 3911 skb->priority = map->priomap[prioidx]; 3912 } 3913 #else 3914 #define skb_update_prio(skb) 3915 #endif 3916 3917 /** 3918 * dev_loopback_xmit - loop back @skb 3919 * @net: network namespace this loopback is happening in 3920 * @sk: sk needed to be a netfilter okfn 3921 * @skb: buffer to transmit 3922 */ 3923 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3924 { 3925 skb_reset_mac_header(skb); 3926 __skb_pull(skb, skb_network_offset(skb)); 3927 skb->pkt_type = PACKET_LOOPBACK; 3928 if (skb->ip_summed == CHECKSUM_NONE) 3929 skb->ip_summed = CHECKSUM_UNNECESSARY; 3930 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 3931 skb_dst_force(skb); 3932 netif_rx(skb); 3933 return 0; 3934 } 3935 EXPORT_SYMBOL(dev_loopback_xmit); 3936 3937 #ifdef CONFIG_NET_EGRESS 3938 static struct sk_buff * 3939 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 3940 { 3941 #ifdef CONFIG_NET_CLS_ACT 3942 struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress); 3943 struct tcf_result cl_res; 3944 3945 if (!miniq) 3946 return skb; 3947 3948 /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */ 3949 tc_skb_cb(skb)->mru = 0; 3950 tc_skb_cb(skb)->post_ct = false; 3951 mini_qdisc_bstats_cpu_update(miniq, skb); 3952 3953 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 3954 case TC_ACT_OK: 3955 case TC_ACT_RECLASSIFY: 3956 skb->tc_index = TC_H_MIN(cl_res.classid); 3957 break; 3958 case TC_ACT_SHOT: 3959 mini_qdisc_qstats_cpu_drop(miniq); 3960 *ret = NET_XMIT_DROP; 3961 kfree_skb_reason(skb, SKB_DROP_REASON_TC_EGRESS); 3962 return NULL; 3963 case TC_ACT_STOLEN: 3964 case TC_ACT_QUEUED: 3965 case TC_ACT_TRAP: 3966 *ret = NET_XMIT_SUCCESS; 3967 consume_skb(skb); 3968 return NULL; 3969 case TC_ACT_REDIRECT: 3970 /* No need to push/pop skb's mac_header here on egress! */ 3971 skb_do_redirect(skb); 3972 *ret = NET_XMIT_SUCCESS; 3973 return NULL; 3974 default: 3975 break; 3976 } 3977 #endif /* CONFIG_NET_CLS_ACT */ 3978 3979 return skb; 3980 } 3981 3982 static struct netdev_queue * 3983 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 3984 { 3985 int qm = skb_get_queue_mapping(skb); 3986 3987 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 3988 } 3989 3990 static bool netdev_xmit_txqueue_skipped(void) 3991 { 3992 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 3993 } 3994 3995 void netdev_xmit_skip_txqueue(bool skip) 3996 { 3997 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 3998 } 3999 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 4000 #endif /* CONFIG_NET_EGRESS */ 4001 4002 #ifdef CONFIG_XPS 4003 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4004 struct xps_dev_maps *dev_maps, unsigned int tci) 4005 { 4006 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4007 struct xps_map *map; 4008 int queue_index = -1; 4009 4010 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4011 return queue_index; 4012 4013 tci *= dev_maps->num_tc; 4014 tci += tc; 4015 4016 map = rcu_dereference(dev_maps->attr_map[tci]); 4017 if (map) { 4018 if (map->len == 1) 4019 queue_index = map->queues[0]; 4020 else 4021 queue_index = map->queues[reciprocal_scale( 4022 skb_get_hash(skb), map->len)]; 4023 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4024 queue_index = -1; 4025 } 4026 return queue_index; 4027 } 4028 #endif 4029 4030 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4031 struct sk_buff *skb) 4032 { 4033 #ifdef CONFIG_XPS 4034 struct xps_dev_maps *dev_maps; 4035 struct sock *sk = skb->sk; 4036 int queue_index = -1; 4037 4038 if (!static_key_false(&xps_needed)) 4039 return -1; 4040 4041 rcu_read_lock(); 4042 if (!static_key_false(&xps_rxqs_needed)) 4043 goto get_cpus_map; 4044 4045 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4046 if (dev_maps) { 4047 int tci = sk_rx_queue_get(sk); 4048 4049 if (tci >= 0) 4050 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4051 tci); 4052 } 4053 4054 get_cpus_map: 4055 if (queue_index < 0) { 4056 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4057 if (dev_maps) { 4058 unsigned int tci = skb->sender_cpu - 1; 4059 4060 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4061 tci); 4062 } 4063 } 4064 rcu_read_unlock(); 4065 4066 return queue_index; 4067 #else 4068 return -1; 4069 #endif 4070 } 4071 4072 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4073 struct net_device *sb_dev) 4074 { 4075 return 0; 4076 } 4077 EXPORT_SYMBOL(dev_pick_tx_zero); 4078 4079 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 4080 struct net_device *sb_dev) 4081 { 4082 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 4083 } 4084 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 4085 4086 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4087 struct net_device *sb_dev) 4088 { 4089 struct sock *sk = skb->sk; 4090 int queue_index = sk_tx_queue_get(sk); 4091 4092 sb_dev = sb_dev ? : dev; 4093 4094 if (queue_index < 0 || skb->ooo_okay || 4095 queue_index >= dev->real_num_tx_queues) { 4096 int new_index = get_xps_queue(dev, sb_dev, skb); 4097 4098 if (new_index < 0) 4099 new_index = skb_tx_hash(dev, sb_dev, skb); 4100 4101 if (queue_index != new_index && sk && 4102 sk_fullsock(sk) && 4103 rcu_access_pointer(sk->sk_dst_cache)) 4104 sk_tx_queue_set(sk, new_index); 4105 4106 queue_index = new_index; 4107 } 4108 4109 return queue_index; 4110 } 4111 EXPORT_SYMBOL(netdev_pick_tx); 4112 4113 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4114 struct sk_buff *skb, 4115 struct net_device *sb_dev) 4116 { 4117 int queue_index = 0; 4118 4119 #ifdef CONFIG_XPS 4120 u32 sender_cpu = skb->sender_cpu - 1; 4121 4122 if (sender_cpu >= (u32)NR_CPUS) 4123 skb->sender_cpu = raw_smp_processor_id() + 1; 4124 #endif 4125 4126 if (dev->real_num_tx_queues != 1) { 4127 const struct net_device_ops *ops = dev->netdev_ops; 4128 4129 if (ops->ndo_select_queue) 4130 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4131 else 4132 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4133 4134 queue_index = netdev_cap_txqueue(dev, queue_index); 4135 } 4136 4137 skb_set_queue_mapping(skb, queue_index); 4138 return netdev_get_tx_queue(dev, queue_index); 4139 } 4140 4141 /** 4142 * __dev_queue_xmit() - transmit a buffer 4143 * @skb: buffer to transmit 4144 * @sb_dev: suboordinate device used for L2 forwarding offload 4145 * 4146 * Queue a buffer for transmission to a network device. The caller must 4147 * have set the device and priority and built the buffer before calling 4148 * this function. The function can be called from an interrupt. 4149 * 4150 * When calling this method, interrupts MUST be enabled. This is because 4151 * the BH enable code must have IRQs enabled so that it will not deadlock. 4152 * 4153 * Regardless of the return value, the skb is consumed, so it is currently 4154 * difficult to retry a send to this method. (You can bump the ref count 4155 * before sending to hold a reference for retry if you are careful.) 4156 * 4157 * Return: 4158 * * 0 - buffer successfully transmitted 4159 * * positive qdisc return code - NET_XMIT_DROP etc. 4160 * * negative errno - other errors 4161 */ 4162 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4163 { 4164 struct net_device *dev = skb->dev; 4165 struct netdev_queue *txq = NULL; 4166 struct Qdisc *q; 4167 int rc = -ENOMEM; 4168 bool again = false; 4169 4170 skb_reset_mac_header(skb); 4171 skb_assert_len(skb); 4172 4173 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4174 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4175 4176 /* Disable soft irqs for various locks below. Also 4177 * stops preemption for RCU. 4178 */ 4179 rcu_read_lock_bh(); 4180 4181 skb_update_prio(skb); 4182 4183 qdisc_pkt_len_init(skb); 4184 #ifdef CONFIG_NET_CLS_ACT 4185 skb->tc_at_ingress = 0; 4186 #endif 4187 #ifdef CONFIG_NET_EGRESS 4188 if (static_branch_unlikely(&egress_needed_key)) { 4189 if (nf_hook_egress_active()) { 4190 skb = nf_hook_egress(skb, &rc, dev); 4191 if (!skb) 4192 goto out; 4193 } 4194 4195 netdev_xmit_skip_txqueue(false); 4196 4197 nf_skip_egress(skb, true); 4198 skb = sch_handle_egress(skb, &rc, dev); 4199 if (!skb) 4200 goto out; 4201 nf_skip_egress(skb, false); 4202 4203 if (netdev_xmit_txqueue_skipped()) 4204 txq = netdev_tx_queue_mapping(dev, skb); 4205 } 4206 #endif 4207 /* If device/qdisc don't need skb->dst, release it right now while 4208 * its hot in this cpu cache. 4209 */ 4210 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4211 skb_dst_drop(skb); 4212 else 4213 skb_dst_force(skb); 4214 4215 if (!txq) 4216 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4217 4218 q = rcu_dereference_bh(txq->qdisc); 4219 4220 trace_net_dev_queue(skb); 4221 if (q->enqueue) { 4222 rc = __dev_xmit_skb(skb, q, dev, txq); 4223 goto out; 4224 } 4225 4226 /* The device has no queue. Common case for software devices: 4227 * loopback, all the sorts of tunnels... 4228 4229 * Really, it is unlikely that netif_tx_lock protection is necessary 4230 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4231 * counters.) 4232 * However, it is possible, that they rely on protection 4233 * made by us here. 4234 4235 * Check this and shot the lock. It is not prone from deadlocks. 4236 *Either shot noqueue qdisc, it is even simpler 8) 4237 */ 4238 if (dev->flags & IFF_UP) { 4239 int cpu = smp_processor_id(); /* ok because BHs are off */ 4240 4241 /* Other cpus might concurrently change txq->xmit_lock_owner 4242 * to -1 or to their cpu id, but not to our id. 4243 */ 4244 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4245 if (dev_xmit_recursion()) 4246 goto recursion_alert; 4247 4248 skb = validate_xmit_skb(skb, dev, &again); 4249 if (!skb) 4250 goto out; 4251 4252 HARD_TX_LOCK(dev, txq, cpu); 4253 4254 if (!netif_xmit_stopped(txq)) { 4255 dev_xmit_recursion_inc(); 4256 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4257 dev_xmit_recursion_dec(); 4258 if (dev_xmit_complete(rc)) { 4259 HARD_TX_UNLOCK(dev, txq); 4260 goto out; 4261 } 4262 } 4263 HARD_TX_UNLOCK(dev, txq); 4264 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4265 dev->name); 4266 } else { 4267 /* Recursion is detected! It is possible, 4268 * unfortunately 4269 */ 4270 recursion_alert: 4271 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4272 dev->name); 4273 } 4274 } 4275 4276 rc = -ENETDOWN; 4277 rcu_read_unlock_bh(); 4278 4279 dev_core_stats_tx_dropped_inc(dev); 4280 kfree_skb_list(skb); 4281 return rc; 4282 out: 4283 rcu_read_unlock_bh(); 4284 return rc; 4285 } 4286 EXPORT_SYMBOL(__dev_queue_xmit); 4287 4288 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4289 { 4290 struct net_device *dev = skb->dev; 4291 struct sk_buff *orig_skb = skb; 4292 struct netdev_queue *txq; 4293 int ret = NETDEV_TX_BUSY; 4294 bool again = false; 4295 4296 if (unlikely(!netif_running(dev) || 4297 !netif_carrier_ok(dev))) 4298 goto drop; 4299 4300 skb = validate_xmit_skb_list(skb, dev, &again); 4301 if (skb != orig_skb) 4302 goto drop; 4303 4304 skb_set_queue_mapping(skb, queue_id); 4305 txq = skb_get_tx_queue(dev, skb); 4306 4307 local_bh_disable(); 4308 4309 dev_xmit_recursion_inc(); 4310 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4311 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4312 ret = netdev_start_xmit(skb, dev, txq, false); 4313 HARD_TX_UNLOCK(dev, txq); 4314 dev_xmit_recursion_dec(); 4315 4316 local_bh_enable(); 4317 return ret; 4318 drop: 4319 dev_core_stats_tx_dropped_inc(dev); 4320 kfree_skb_list(skb); 4321 return NET_XMIT_DROP; 4322 } 4323 EXPORT_SYMBOL(__dev_direct_xmit); 4324 4325 /************************************************************************* 4326 * Receiver routines 4327 *************************************************************************/ 4328 4329 int netdev_max_backlog __read_mostly = 1000; 4330 EXPORT_SYMBOL(netdev_max_backlog); 4331 4332 int netdev_tstamp_prequeue __read_mostly = 1; 4333 unsigned int sysctl_skb_defer_max __read_mostly = 64; 4334 int netdev_budget __read_mostly = 300; 4335 /* Must be at least 2 jiffes to guarantee 1 jiffy timeout */ 4336 unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ; 4337 int weight_p __read_mostly = 64; /* old backlog weight */ 4338 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4339 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4340 int dev_rx_weight __read_mostly = 64; 4341 int dev_tx_weight __read_mostly = 64; 4342 4343 /* Called with irq disabled */ 4344 static inline void ____napi_schedule(struct softnet_data *sd, 4345 struct napi_struct *napi) 4346 { 4347 struct task_struct *thread; 4348 4349 lockdep_assert_irqs_disabled(); 4350 4351 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4352 /* Paired with smp_mb__before_atomic() in 4353 * napi_enable()/dev_set_threaded(). 4354 * Use READ_ONCE() to guarantee a complete 4355 * read on napi->thread. Only call 4356 * wake_up_process() when it's not NULL. 4357 */ 4358 thread = READ_ONCE(napi->thread); 4359 if (thread) { 4360 /* Avoid doing set_bit() if the thread is in 4361 * INTERRUPTIBLE state, cause napi_thread_wait() 4362 * makes sure to proceed with napi polling 4363 * if the thread is explicitly woken from here. 4364 */ 4365 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE) 4366 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4367 wake_up_process(thread); 4368 return; 4369 } 4370 } 4371 4372 list_add_tail(&napi->poll_list, &sd->poll_list); 4373 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4374 } 4375 4376 #ifdef CONFIG_RPS 4377 4378 /* One global table that all flow-based protocols share. */ 4379 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 4380 EXPORT_SYMBOL(rps_sock_flow_table); 4381 u32 rps_cpu_mask __read_mostly; 4382 EXPORT_SYMBOL(rps_cpu_mask); 4383 4384 struct static_key_false rps_needed __read_mostly; 4385 EXPORT_SYMBOL(rps_needed); 4386 struct static_key_false rfs_needed __read_mostly; 4387 EXPORT_SYMBOL(rfs_needed); 4388 4389 static struct rps_dev_flow * 4390 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4391 struct rps_dev_flow *rflow, u16 next_cpu) 4392 { 4393 if (next_cpu < nr_cpu_ids) { 4394 #ifdef CONFIG_RFS_ACCEL 4395 struct netdev_rx_queue *rxqueue; 4396 struct rps_dev_flow_table *flow_table; 4397 struct rps_dev_flow *old_rflow; 4398 u32 flow_id; 4399 u16 rxq_index; 4400 int rc; 4401 4402 /* Should we steer this flow to a different hardware queue? */ 4403 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4404 !(dev->features & NETIF_F_NTUPLE)) 4405 goto out; 4406 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4407 if (rxq_index == skb_get_rx_queue(skb)) 4408 goto out; 4409 4410 rxqueue = dev->_rx + rxq_index; 4411 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4412 if (!flow_table) 4413 goto out; 4414 flow_id = skb_get_hash(skb) & flow_table->mask; 4415 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4416 rxq_index, flow_id); 4417 if (rc < 0) 4418 goto out; 4419 old_rflow = rflow; 4420 rflow = &flow_table->flows[flow_id]; 4421 rflow->filter = rc; 4422 if (old_rflow->filter == rflow->filter) 4423 old_rflow->filter = RPS_NO_FILTER; 4424 out: 4425 #endif 4426 rflow->last_qtail = 4427 per_cpu(softnet_data, next_cpu).input_queue_head; 4428 } 4429 4430 rflow->cpu = next_cpu; 4431 return rflow; 4432 } 4433 4434 /* 4435 * get_rps_cpu is called from netif_receive_skb and returns the target 4436 * CPU from the RPS map of the receiving queue for a given skb. 4437 * rcu_read_lock must be held on entry. 4438 */ 4439 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4440 struct rps_dev_flow **rflowp) 4441 { 4442 const struct rps_sock_flow_table *sock_flow_table; 4443 struct netdev_rx_queue *rxqueue = dev->_rx; 4444 struct rps_dev_flow_table *flow_table; 4445 struct rps_map *map; 4446 int cpu = -1; 4447 u32 tcpu; 4448 u32 hash; 4449 4450 if (skb_rx_queue_recorded(skb)) { 4451 u16 index = skb_get_rx_queue(skb); 4452 4453 if (unlikely(index >= dev->real_num_rx_queues)) { 4454 WARN_ONCE(dev->real_num_rx_queues > 1, 4455 "%s received packet on queue %u, but number " 4456 "of RX queues is %u\n", 4457 dev->name, index, dev->real_num_rx_queues); 4458 goto done; 4459 } 4460 rxqueue += index; 4461 } 4462 4463 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4464 4465 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4466 map = rcu_dereference(rxqueue->rps_map); 4467 if (!flow_table && !map) 4468 goto done; 4469 4470 skb_reset_network_header(skb); 4471 hash = skb_get_hash(skb); 4472 if (!hash) 4473 goto done; 4474 4475 sock_flow_table = rcu_dereference(rps_sock_flow_table); 4476 if (flow_table && sock_flow_table) { 4477 struct rps_dev_flow *rflow; 4478 u32 next_cpu; 4479 u32 ident; 4480 4481 /* First check into global flow table if there is a match */ 4482 ident = sock_flow_table->ents[hash & sock_flow_table->mask]; 4483 if ((ident ^ hash) & ~rps_cpu_mask) 4484 goto try_rps; 4485 4486 next_cpu = ident & rps_cpu_mask; 4487 4488 /* OK, now we know there is a match, 4489 * we can look at the local (per receive queue) flow table 4490 */ 4491 rflow = &flow_table->flows[hash & flow_table->mask]; 4492 tcpu = rflow->cpu; 4493 4494 /* 4495 * If the desired CPU (where last recvmsg was done) is 4496 * different from current CPU (one in the rx-queue flow 4497 * table entry), switch if one of the following holds: 4498 * - Current CPU is unset (>= nr_cpu_ids). 4499 * - Current CPU is offline. 4500 * - The current CPU's queue tail has advanced beyond the 4501 * last packet that was enqueued using this table entry. 4502 * This guarantees that all previous packets for the flow 4503 * have been dequeued, thus preserving in order delivery. 4504 */ 4505 if (unlikely(tcpu != next_cpu) && 4506 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4507 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 4508 rflow->last_qtail)) >= 0)) { 4509 tcpu = next_cpu; 4510 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4511 } 4512 4513 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4514 *rflowp = rflow; 4515 cpu = tcpu; 4516 goto done; 4517 } 4518 } 4519 4520 try_rps: 4521 4522 if (map) { 4523 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4524 if (cpu_online(tcpu)) { 4525 cpu = tcpu; 4526 goto done; 4527 } 4528 } 4529 4530 done: 4531 return cpu; 4532 } 4533 4534 #ifdef CONFIG_RFS_ACCEL 4535 4536 /** 4537 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4538 * @dev: Device on which the filter was set 4539 * @rxq_index: RX queue index 4540 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4541 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4542 * 4543 * Drivers that implement ndo_rx_flow_steer() should periodically call 4544 * this function for each installed filter and remove the filters for 4545 * which it returns %true. 4546 */ 4547 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4548 u32 flow_id, u16 filter_id) 4549 { 4550 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4551 struct rps_dev_flow_table *flow_table; 4552 struct rps_dev_flow *rflow; 4553 bool expire = true; 4554 unsigned int cpu; 4555 4556 rcu_read_lock(); 4557 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4558 if (flow_table && flow_id <= flow_table->mask) { 4559 rflow = &flow_table->flows[flow_id]; 4560 cpu = READ_ONCE(rflow->cpu); 4561 if (rflow->filter == filter_id && cpu < nr_cpu_ids && 4562 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 4563 rflow->last_qtail) < 4564 (int)(10 * flow_table->mask))) 4565 expire = false; 4566 } 4567 rcu_read_unlock(); 4568 return expire; 4569 } 4570 EXPORT_SYMBOL(rps_may_expire_flow); 4571 4572 #endif /* CONFIG_RFS_ACCEL */ 4573 4574 /* Called from hardirq (IPI) context */ 4575 static void rps_trigger_softirq(void *data) 4576 { 4577 struct softnet_data *sd = data; 4578 4579 ____napi_schedule(sd, &sd->backlog); 4580 sd->received_rps++; 4581 } 4582 4583 #endif /* CONFIG_RPS */ 4584 4585 /* Called from hardirq (IPI) context */ 4586 static void trigger_rx_softirq(void *data) 4587 { 4588 struct softnet_data *sd = data; 4589 4590 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4591 smp_store_release(&sd->defer_ipi_scheduled, 0); 4592 } 4593 4594 /* 4595 * Check if this softnet_data structure is another cpu one 4596 * If yes, queue it to our IPI list and return 1 4597 * If no, return 0 4598 */ 4599 static int napi_schedule_rps(struct softnet_data *sd) 4600 { 4601 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4602 4603 #ifdef CONFIG_RPS 4604 if (sd != mysd) { 4605 sd->rps_ipi_next = mysd->rps_ipi_list; 4606 mysd->rps_ipi_list = sd; 4607 4608 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4609 return 1; 4610 } 4611 #endif /* CONFIG_RPS */ 4612 __napi_schedule_irqoff(&mysd->backlog); 4613 return 0; 4614 } 4615 4616 #ifdef CONFIG_NET_FLOW_LIMIT 4617 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4618 #endif 4619 4620 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4621 { 4622 #ifdef CONFIG_NET_FLOW_LIMIT 4623 struct sd_flow_limit *fl; 4624 struct softnet_data *sd; 4625 unsigned int old_flow, new_flow; 4626 4627 if (qlen < (READ_ONCE(netdev_max_backlog) >> 1)) 4628 return false; 4629 4630 sd = this_cpu_ptr(&softnet_data); 4631 4632 rcu_read_lock(); 4633 fl = rcu_dereference(sd->flow_limit); 4634 if (fl) { 4635 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4636 old_flow = fl->history[fl->history_head]; 4637 fl->history[fl->history_head] = new_flow; 4638 4639 fl->history_head++; 4640 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4641 4642 if (likely(fl->buckets[old_flow])) 4643 fl->buckets[old_flow]--; 4644 4645 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4646 fl->count++; 4647 rcu_read_unlock(); 4648 return true; 4649 } 4650 } 4651 rcu_read_unlock(); 4652 #endif 4653 return false; 4654 } 4655 4656 /* 4657 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4658 * queue (may be a remote CPU queue). 4659 */ 4660 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4661 unsigned int *qtail) 4662 { 4663 enum skb_drop_reason reason; 4664 struct softnet_data *sd; 4665 unsigned long flags; 4666 unsigned int qlen; 4667 4668 reason = SKB_DROP_REASON_NOT_SPECIFIED; 4669 sd = &per_cpu(softnet_data, cpu); 4670 4671 rps_lock_irqsave(sd, &flags); 4672 if (!netif_running(skb->dev)) 4673 goto drop; 4674 qlen = skb_queue_len(&sd->input_pkt_queue); 4675 if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) { 4676 if (qlen) { 4677 enqueue: 4678 __skb_queue_tail(&sd->input_pkt_queue, skb); 4679 input_queue_tail_incr_save(sd, qtail); 4680 rps_unlock_irq_restore(sd, &flags); 4681 return NET_RX_SUCCESS; 4682 } 4683 4684 /* Schedule NAPI for backlog device 4685 * We can use non atomic operation since we own the queue lock 4686 */ 4687 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 4688 napi_schedule_rps(sd); 4689 goto enqueue; 4690 } 4691 reason = SKB_DROP_REASON_CPU_BACKLOG; 4692 4693 drop: 4694 sd->dropped++; 4695 rps_unlock_irq_restore(sd, &flags); 4696 4697 dev_core_stats_rx_dropped_inc(skb->dev); 4698 kfree_skb_reason(skb, reason); 4699 return NET_RX_DROP; 4700 } 4701 4702 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4703 { 4704 struct net_device *dev = skb->dev; 4705 struct netdev_rx_queue *rxqueue; 4706 4707 rxqueue = dev->_rx; 4708 4709 if (skb_rx_queue_recorded(skb)) { 4710 u16 index = skb_get_rx_queue(skb); 4711 4712 if (unlikely(index >= dev->real_num_rx_queues)) { 4713 WARN_ONCE(dev->real_num_rx_queues > 1, 4714 "%s received packet on queue %u, but number " 4715 "of RX queues is %u\n", 4716 dev->name, index, dev->real_num_rx_queues); 4717 4718 return rxqueue; /* Return first rxqueue */ 4719 } 4720 rxqueue += index; 4721 } 4722 return rxqueue; 4723 } 4724 4725 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4726 struct bpf_prog *xdp_prog) 4727 { 4728 void *orig_data, *orig_data_end, *hard_start; 4729 struct netdev_rx_queue *rxqueue; 4730 bool orig_bcast, orig_host; 4731 u32 mac_len, frame_sz; 4732 __be16 orig_eth_type; 4733 struct ethhdr *eth; 4734 u32 metalen, act; 4735 int off; 4736 4737 /* The XDP program wants to see the packet starting at the MAC 4738 * header. 4739 */ 4740 mac_len = skb->data - skb_mac_header(skb); 4741 hard_start = skb->data - skb_headroom(skb); 4742 4743 /* SKB "head" area always have tailroom for skb_shared_info */ 4744 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4745 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4746 4747 rxqueue = netif_get_rxqueue(skb); 4748 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4749 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4750 skb_headlen(skb) + mac_len, true); 4751 4752 orig_data_end = xdp->data_end; 4753 orig_data = xdp->data; 4754 eth = (struct ethhdr *)xdp->data; 4755 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4756 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4757 orig_eth_type = eth->h_proto; 4758 4759 act = bpf_prog_run_xdp(xdp_prog, xdp); 4760 4761 /* check if bpf_xdp_adjust_head was used */ 4762 off = xdp->data - orig_data; 4763 if (off) { 4764 if (off > 0) 4765 __skb_pull(skb, off); 4766 else if (off < 0) 4767 __skb_push(skb, -off); 4768 4769 skb->mac_header += off; 4770 skb_reset_network_header(skb); 4771 } 4772 4773 /* check if bpf_xdp_adjust_tail was used */ 4774 off = xdp->data_end - orig_data_end; 4775 if (off != 0) { 4776 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4777 skb->len += off; /* positive on grow, negative on shrink */ 4778 } 4779 4780 /* check if XDP changed eth hdr such SKB needs update */ 4781 eth = (struct ethhdr *)xdp->data; 4782 if ((orig_eth_type != eth->h_proto) || 4783 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4784 skb->dev->dev_addr)) || 4785 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4786 __skb_push(skb, ETH_HLEN); 4787 skb->pkt_type = PACKET_HOST; 4788 skb->protocol = eth_type_trans(skb, skb->dev); 4789 } 4790 4791 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4792 * before calling us again on redirect path. We do not call do_redirect 4793 * as we leave that up to the caller. 4794 * 4795 * Caller is responsible for managing lifetime of skb (i.e. calling 4796 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4797 */ 4798 switch (act) { 4799 case XDP_REDIRECT: 4800 case XDP_TX: 4801 __skb_push(skb, mac_len); 4802 break; 4803 case XDP_PASS: 4804 metalen = xdp->data - xdp->data_meta; 4805 if (metalen) 4806 skb_metadata_set(skb, metalen); 4807 break; 4808 } 4809 4810 return act; 4811 } 4812 4813 static u32 netif_receive_generic_xdp(struct sk_buff *skb, 4814 struct xdp_buff *xdp, 4815 struct bpf_prog *xdp_prog) 4816 { 4817 u32 act = XDP_DROP; 4818 4819 /* Reinjected packets coming from act_mirred or similar should 4820 * not get XDP generic processing. 4821 */ 4822 if (skb_is_redirected(skb)) 4823 return XDP_PASS; 4824 4825 /* XDP packets must be linear and must have sufficient headroom 4826 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also 4827 * native XDP provides, thus we need to do it here as well. 4828 */ 4829 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 4830 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 4831 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 4832 int troom = skb->tail + skb->data_len - skb->end; 4833 4834 /* In case we have to go down the path and also linearize, 4835 * then lets do the pskb_expand_head() work just once here. 4836 */ 4837 if (pskb_expand_head(skb, 4838 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 4839 troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) 4840 goto do_drop; 4841 if (skb_linearize(skb)) 4842 goto do_drop; 4843 } 4844 4845 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog); 4846 switch (act) { 4847 case XDP_REDIRECT: 4848 case XDP_TX: 4849 case XDP_PASS: 4850 break; 4851 default: 4852 bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act); 4853 fallthrough; 4854 case XDP_ABORTED: 4855 trace_xdp_exception(skb->dev, xdp_prog, act); 4856 fallthrough; 4857 case XDP_DROP: 4858 do_drop: 4859 kfree_skb(skb); 4860 break; 4861 } 4862 4863 return act; 4864 } 4865 4866 /* When doing generic XDP we have to bypass the qdisc layer and the 4867 * network taps in order to match in-driver-XDP behavior. This also means 4868 * that XDP packets are able to starve other packets going through a qdisc, 4869 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 4870 * queues, so they do not have this starvation issue. 4871 */ 4872 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 4873 { 4874 struct net_device *dev = skb->dev; 4875 struct netdev_queue *txq; 4876 bool free_skb = true; 4877 int cpu, rc; 4878 4879 txq = netdev_core_pick_tx(dev, skb, NULL); 4880 cpu = smp_processor_id(); 4881 HARD_TX_LOCK(dev, txq, cpu); 4882 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 4883 rc = netdev_start_xmit(skb, dev, txq, 0); 4884 if (dev_xmit_complete(rc)) 4885 free_skb = false; 4886 } 4887 HARD_TX_UNLOCK(dev, txq); 4888 if (free_skb) { 4889 trace_xdp_exception(dev, xdp_prog, XDP_TX); 4890 dev_core_stats_tx_dropped_inc(dev); 4891 kfree_skb(skb); 4892 } 4893 } 4894 4895 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 4896 4897 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) 4898 { 4899 if (xdp_prog) { 4900 struct xdp_buff xdp; 4901 u32 act; 4902 int err; 4903 4904 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); 4905 if (act != XDP_PASS) { 4906 switch (act) { 4907 case XDP_REDIRECT: 4908 err = xdp_do_generic_redirect(skb->dev, skb, 4909 &xdp, xdp_prog); 4910 if (err) 4911 goto out_redir; 4912 break; 4913 case XDP_TX: 4914 generic_xdp_tx(skb, xdp_prog); 4915 break; 4916 } 4917 return XDP_DROP; 4918 } 4919 } 4920 return XDP_PASS; 4921 out_redir: 4922 kfree_skb_reason(skb, SKB_DROP_REASON_XDP); 4923 return XDP_DROP; 4924 } 4925 EXPORT_SYMBOL_GPL(do_xdp_generic); 4926 4927 static int netif_rx_internal(struct sk_buff *skb) 4928 { 4929 int ret; 4930 4931 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 4932 4933 trace_netif_rx(skb); 4934 4935 #ifdef CONFIG_RPS 4936 if (static_branch_unlikely(&rps_needed)) { 4937 struct rps_dev_flow voidflow, *rflow = &voidflow; 4938 int cpu; 4939 4940 rcu_read_lock(); 4941 4942 cpu = get_rps_cpu(skb->dev, skb, &rflow); 4943 if (cpu < 0) 4944 cpu = smp_processor_id(); 4945 4946 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 4947 4948 rcu_read_unlock(); 4949 } else 4950 #endif 4951 { 4952 unsigned int qtail; 4953 4954 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 4955 } 4956 return ret; 4957 } 4958 4959 /** 4960 * __netif_rx - Slightly optimized version of netif_rx 4961 * @skb: buffer to post 4962 * 4963 * This behaves as netif_rx except that it does not disable bottom halves. 4964 * As a result this function may only be invoked from the interrupt context 4965 * (either hard or soft interrupt). 4966 */ 4967 int __netif_rx(struct sk_buff *skb) 4968 { 4969 int ret; 4970 4971 lockdep_assert_once(hardirq_count() | softirq_count()); 4972 4973 trace_netif_rx_entry(skb); 4974 ret = netif_rx_internal(skb); 4975 trace_netif_rx_exit(ret); 4976 return ret; 4977 } 4978 EXPORT_SYMBOL(__netif_rx); 4979 4980 /** 4981 * netif_rx - post buffer to the network code 4982 * @skb: buffer to post 4983 * 4984 * This function receives a packet from a device driver and queues it for 4985 * the upper (protocol) levels to process via the backlog NAPI device. It 4986 * always succeeds. The buffer may be dropped during processing for 4987 * congestion control or by the protocol layers. 4988 * The network buffer is passed via the backlog NAPI device. Modern NIC 4989 * driver should use NAPI and GRO. 4990 * This function can used from interrupt and from process context. The 4991 * caller from process context must not disable interrupts before invoking 4992 * this function. 4993 * 4994 * return values: 4995 * NET_RX_SUCCESS (no congestion) 4996 * NET_RX_DROP (packet was dropped) 4997 * 4998 */ 4999 int netif_rx(struct sk_buff *skb) 5000 { 5001 bool need_bh_off = !(hardirq_count() | softirq_count()); 5002 int ret; 5003 5004 if (need_bh_off) 5005 local_bh_disable(); 5006 trace_netif_rx_entry(skb); 5007 ret = netif_rx_internal(skb); 5008 trace_netif_rx_exit(ret); 5009 if (need_bh_off) 5010 local_bh_enable(); 5011 return ret; 5012 } 5013 EXPORT_SYMBOL(netif_rx); 5014 5015 static __latent_entropy void net_tx_action(struct softirq_action *h) 5016 { 5017 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5018 5019 if (sd->completion_queue) { 5020 struct sk_buff *clist; 5021 5022 local_irq_disable(); 5023 clist = sd->completion_queue; 5024 sd->completion_queue = NULL; 5025 local_irq_enable(); 5026 5027 while (clist) { 5028 struct sk_buff *skb = clist; 5029 5030 clist = clist->next; 5031 5032 WARN_ON(refcount_read(&skb->users)); 5033 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED)) 5034 trace_consume_skb(skb); 5035 else 5036 trace_kfree_skb(skb, net_tx_action, 5037 SKB_DROP_REASON_NOT_SPECIFIED); 5038 5039 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5040 __kfree_skb(skb); 5041 else 5042 __kfree_skb_defer(skb); 5043 } 5044 } 5045 5046 if (sd->output_queue) { 5047 struct Qdisc *head; 5048 5049 local_irq_disable(); 5050 head = sd->output_queue; 5051 sd->output_queue = NULL; 5052 sd->output_queue_tailp = &sd->output_queue; 5053 local_irq_enable(); 5054 5055 rcu_read_lock(); 5056 5057 while (head) { 5058 struct Qdisc *q = head; 5059 spinlock_t *root_lock = NULL; 5060 5061 head = head->next_sched; 5062 5063 /* We need to make sure head->next_sched is read 5064 * before clearing __QDISC_STATE_SCHED 5065 */ 5066 smp_mb__before_atomic(); 5067 5068 if (!(q->flags & TCQ_F_NOLOCK)) { 5069 root_lock = qdisc_lock(q); 5070 spin_lock(root_lock); 5071 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5072 &q->state))) { 5073 /* There is a synchronize_net() between 5074 * STATE_DEACTIVATED flag being set and 5075 * qdisc_reset()/some_qdisc_is_busy() in 5076 * dev_deactivate(), so we can safely bail out 5077 * early here to avoid data race between 5078 * qdisc_deactivate() and some_qdisc_is_busy() 5079 * for lockless qdisc. 5080 */ 5081 clear_bit(__QDISC_STATE_SCHED, &q->state); 5082 continue; 5083 } 5084 5085 clear_bit(__QDISC_STATE_SCHED, &q->state); 5086 qdisc_run(q); 5087 if (root_lock) 5088 spin_unlock(root_lock); 5089 } 5090 5091 rcu_read_unlock(); 5092 } 5093 5094 xfrm_dev_backlog(sd); 5095 } 5096 5097 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5098 /* This hook is defined here for ATM LANE */ 5099 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5100 unsigned char *addr) __read_mostly; 5101 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5102 #endif 5103 5104 static inline struct sk_buff * 5105 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 5106 struct net_device *orig_dev, bool *another) 5107 { 5108 #ifdef CONFIG_NET_CLS_ACT 5109 struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress); 5110 struct tcf_result cl_res; 5111 5112 /* If there's at least one ingress present somewhere (so 5113 * we get here via enabled static key), remaining devices 5114 * that are not configured with an ingress qdisc will bail 5115 * out here. 5116 */ 5117 if (!miniq) 5118 return skb; 5119 5120 if (*pt_prev) { 5121 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5122 *pt_prev = NULL; 5123 } 5124 5125 qdisc_skb_cb(skb)->pkt_len = skb->len; 5126 tc_skb_cb(skb)->mru = 0; 5127 tc_skb_cb(skb)->post_ct = false; 5128 skb->tc_at_ingress = 1; 5129 mini_qdisc_bstats_cpu_update(miniq, skb); 5130 5131 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 5132 case TC_ACT_OK: 5133 case TC_ACT_RECLASSIFY: 5134 skb->tc_index = TC_H_MIN(cl_res.classid); 5135 break; 5136 case TC_ACT_SHOT: 5137 mini_qdisc_qstats_cpu_drop(miniq); 5138 kfree_skb_reason(skb, SKB_DROP_REASON_TC_INGRESS); 5139 *ret = NET_RX_DROP; 5140 return NULL; 5141 case TC_ACT_STOLEN: 5142 case TC_ACT_QUEUED: 5143 case TC_ACT_TRAP: 5144 consume_skb(skb); 5145 *ret = NET_RX_SUCCESS; 5146 return NULL; 5147 case TC_ACT_REDIRECT: 5148 /* skb_mac_header check was done by cls/act_bpf, so 5149 * we can safely push the L2 header back before 5150 * redirecting to another netdev 5151 */ 5152 __skb_push(skb, skb->mac_len); 5153 if (skb_do_redirect(skb) == -EAGAIN) { 5154 __skb_pull(skb, skb->mac_len); 5155 *another = true; 5156 break; 5157 } 5158 *ret = NET_RX_SUCCESS; 5159 return NULL; 5160 case TC_ACT_CONSUMED: 5161 *ret = NET_RX_SUCCESS; 5162 return NULL; 5163 default: 5164 break; 5165 } 5166 #endif /* CONFIG_NET_CLS_ACT */ 5167 return skb; 5168 } 5169 5170 /** 5171 * netdev_is_rx_handler_busy - check if receive handler is registered 5172 * @dev: device to check 5173 * 5174 * Check if a receive handler is already registered for a given device. 5175 * Return true if there one. 5176 * 5177 * The caller must hold the rtnl_mutex. 5178 */ 5179 bool netdev_is_rx_handler_busy(struct net_device *dev) 5180 { 5181 ASSERT_RTNL(); 5182 return dev && rtnl_dereference(dev->rx_handler); 5183 } 5184 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5185 5186 /** 5187 * netdev_rx_handler_register - register receive handler 5188 * @dev: device to register a handler for 5189 * @rx_handler: receive handler to register 5190 * @rx_handler_data: data pointer that is used by rx handler 5191 * 5192 * Register a receive handler for a device. This handler will then be 5193 * called from __netif_receive_skb. A negative errno code is returned 5194 * on a failure. 5195 * 5196 * The caller must hold the rtnl_mutex. 5197 * 5198 * For a general description of rx_handler, see enum rx_handler_result. 5199 */ 5200 int netdev_rx_handler_register(struct net_device *dev, 5201 rx_handler_func_t *rx_handler, 5202 void *rx_handler_data) 5203 { 5204 if (netdev_is_rx_handler_busy(dev)) 5205 return -EBUSY; 5206 5207 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5208 return -EINVAL; 5209 5210 /* Note: rx_handler_data must be set before rx_handler */ 5211 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5212 rcu_assign_pointer(dev->rx_handler, rx_handler); 5213 5214 return 0; 5215 } 5216 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5217 5218 /** 5219 * netdev_rx_handler_unregister - unregister receive handler 5220 * @dev: device to unregister a handler from 5221 * 5222 * Unregister a receive handler from a device. 5223 * 5224 * The caller must hold the rtnl_mutex. 5225 */ 5226 void netdev_rx_handler_unregister(struct net_device *dev) 5227 { 5228 5229 ASSERT_RTNL(); 5230 RCU_INIT_POINTER(dev->rx_handler, NULL); 5231 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5232 * section has a guarantee to see a non NULL rx_handler_data 5233 * as well. 5234 */ 5235 synchronize_net(); 5236 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5237 } 5238 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5239 5240 /* 5241 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5242 * the special handling of PFMEMALLOC skbs. 5243 */ 5244 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5245 { 5246 switch (skb->protocol) { 5247 case htons(ETH_P_ARP): 5248 case htons(ETH_P_IP): 5249 case htons(ETH_P_IPV6): 5250 case htons(ETH_P_8021Q): 5251 case htons(ETH_P_8021AD): 5252 return true; 5253 default: 5254 return false; 5255 } 5256 } 5257 5258 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5259 int *ret, struct net_device *orig_dev) 5260 { 5261 if (nf_hook_ingress_active(skb)) { 5262 int ingress_retval; 5263 5264 if (*pt_prev) { 5265 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5266 *pt_prev = NULL; 5267 } 5268 5269 rcu_read_lock(); 5270 ingress_retval = nf_hook_ingress(skb); 5271 rcu_read_unlock(); 5272 return ingress_retval; 5273 } 5274 return 0; 5275 } 5276 5277 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5278 struct packet_type **ppt_prev) 5279 { 5280 struct packet_type *ptype, *pt_prev; 5281 rx_handler_func_t *rx_handler; 5282 struct sk_buff *skb = *pskb; 5283 struct net_device *orig_dev; 5284 bool deliver_exact = false; 5285 int ret = NET_RX_DROP; 5286 __be16 type; 5287 5288 net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb); 5289 5290 trace_netif_receive_skb(skb); 5291 5292 orig_dev = skb->dev; 5293 5294 skb_reset_network_header(skb); 5295 if (!skb_transport_header_was_set(skb)) 5296 skb_reset_transport_header(skb); 5297 skb_reset_mac_len(skb); 5298 5299 pt_prev = NULL; 5300 5301 another_round: 5302 skb->skb_iif = skb->dev->ifindex; 5303 5304 __this_cpu_inc(softnet_data.processed); 5305 5306 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5307 int ret2; 5308 5309 migrate_disable(); 5310 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); 5311 migrate_enable(); 5312 5313 if (ret2 != XDP_PASS) { 5314 ret = NET_RX_DROP; 5315 goto out; 5316 } 5317 } 5318 5319 if (eth_type_vlan(skb->protocol)) { 5320 skb = skb_vlan_untag(skb); 5321 if (unlikely(!skb)) 5322 goto out; 5323 } 5324 5325 if (skb_skip_tc_classify(skb)) 5326 goto skip_classify; 5327 5328 if (pfmemalloc) 5329 goto skip_taps; 5330 5331 list_for_each_entry_rcu(ptype, &ptype_all, list) { 5332 if (pt_prev) 5333 ret = deliver_skb(skb, pt_prev, orig_dev); 5334 pt_prev = ptype; 5335 } 5336 5337 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5338 if (pt_prev) 5339 ret = deliver_skb(skb, pt_prev, orig_dev); 5340 pt_prev = ptype; 5341 } 5342 5343 skip_taps: 5344 #ifdef CONFIG_NET_INGRESS 5345 if (static_branch_unlikely(&ingress_needed_key)) { 5346 bool another = false; 5347 5348 nf_skip_egress(skb, true); 5349 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5350 &another); 5351 if (another) 5352 goto another_round; 5353 if (!skb) 5354 goto out; 5355 5356 nf_skip_egress(skb, false); 5357 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5358 goto out; 5359 } 5360 #endif 5361 skb_reset_redirect(skb); 5362 skip_classify: 5363 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5364 goto drop; 5365 5366 if (skb_vlan_tag_present(skb)) { 5367 if (pt_prev) { 5368 ret = deliver_skb(skb, pt_prev, orig_dev); 5369 pt_prev = NULL; 5370 } 5371 if (vlan_do_receive(&skb)) 5372 goto another_round; 5373 else if (unlikely(!skb)) 5374 goto out; 5375 } 5376 5377 rx_handler = rcu_dereference(skb->dev->rx_handler); 5378 if (rx_handler) { 5379 if (pt_prev) { 5380 ret = deliver_skb(skb, pt_prev, orig_dev); 5381 pt_prev = NULL; 5382 } 5383 switch (rx_handler(&skb)) { 5384 case RX_HANDLER_CONSUMED: 5385 ret = NET_RX_SUCCESS; 5386 goto out; 5387 case RX_HANDLER_ANOTHER: 5388 goto another_round; 5389 case RX_HANDLER_EXACT: 5390 deliver_exact = true; 5391 break; 5392 case RX_HANDLER_PASS: 5393 break; 5394 default: 5395 BUG(); 5396 } 5397 } 5398 5399 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5400 check_vlan_id: 5401 if (skb_vlan_tag_get_id(skb)) { 5402 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5403 * find vlan device. 5404 */ 5405 skb->pkt_type = PACKET_OTHERHOST; 5406 } else if (eth_type_vlan(skb->protocol)) { 5407 /* Outer header is 802.1P with vlan 0, inner header is 5408 * 802.1Q or 802.1AD and vlan_do_receive() above could 5409 * not find vlan dev for vlan id 0. 5410 */ 5411 __vlan_hwaccel_clear_tag(skb); 5412 skb = skb_vlan_untag(skb); 5413 if (unlikely(!skb)) 5414 goto out; 5415 if (vlan_do_receive(&skb)) 5416 /* After stripping off 802.1P header with vlan 0 5417 * vlan dev is found for inner header. 5418 */ 5419 goto another_round; 5420 else if (unlikely(!skb)) 5421 goto out; 5422 else 5423 /* We have stripped outer 802.1P vlan 0 header. 5424 * But could not find vlan dev. 5425 * check again for vlan id to set OTHERHOST. 5426 */ 5427 goto check_vlan_id; 5428 } 5429 /* Note: we might in the future use prio bits 5430 * and set skb->priority like in vlan_do_receive() 5431 * For the time being, just ignore Priority Code Point 5432 */ 5433 __vlan_hwaccel_clear_tag(skb); 5434 } 5435 5436 type = skb->protocol; 5437 5438 /* deliver only exact match when indicated */ 5439 if (likely(!deliver_exact)) { 5440 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5441 &ptype_base[ntohs(type) & 5442 PTYPE_HASH_MASK]); 5443 } 5444 5445 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5446 &orig_dev->ptype_specific); 5447 5448 if (unlikely(skb->dev != orig_dev)) { 5449 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5450 &skb->dev->ptype_specific); 5451 } 5452 5453 if (pt_prev) { 5454 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5455 goto drop; 5456 *ppt_prev = pt_prev; 5457 } else { 5458 drop: 5459 if (!deliver_exact) 5460 dev_core_stats_rx_dropped_inc(skb->dev); 5461 else 5462 dev_core_stats_rx_nohandler_inc(skb->dev); 5463 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5464 /* Jamal, now you will not able to escape explaining 5465 * me how you were going to use this. :-) 5466 */ 5467 ret = NET_RX_DROP; 5468 } 5469 5470 out: 5471 /* The invariant here is that if *ppt_prev is not NULL 5472 * then skb should also be non-NULL. 5473 * 5474 * Apparently *ppt_prev assignment above holds this invariant due to 5475 * skb dereferencing near it. 5476 */ 5477 *pskb = skb; 5478 return ret; 5479 } 5480 5481 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5482 { 5483 struct net_device *orig_dev = skb->dev; 5484 struct packet_type *pt_prev = NULL; 5485 int ret; 5486 5487 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5488 if (pt_prev) 5489 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5490 skb->dev, pt_prev, orig_dev); 5491 return ret; 5492 } 5493 5494 /** 5495 * netif_receive_skb_core - special purpose version of netif_receive_skb 5496 * @skb: buffer to process 5497 * 5498 * More direct receive version of netif_receive_skb(). It should 5499 * only be used by callers that have a need to skip RPS and Generic XDP. 5500 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5501 * 5502 * This function may only be called from softirq context and interrupts 5503 * should be enabled. 5504 * 5505 * Return values (usually ignored): 5506 * NET_RX_SUCCESS: no congestion 5507 * NET_RX_DROP: packet was dropped 5508 */ 5509 int netif_receive_skb_core(struct sk_buff *skb) 5510 { 5511 int ret; 5512 5513 rcu_read_lock(); 5514 ret = __netif_receive_skb_one_core(skb, false); 5515 rcu_read_unlock(); 5516 5517 return ret; 5518 } 5519 EXPORT_SYMBOL(netif_receive_skb_core); 5520 5521 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5522 struct packet_type *pt_prev, 5523 struct net_device *orig_dev) 5524 { 5525 struct sk_buff *skb, *next; 5526 5527 if (!pt_prev) 5528 return; 5529 if (list_empty(head)) 5530 return; 5531 if (pt_prev->list_func != NULL) 5532 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5533 ip_list_rcv, head, pt_prev, orig_dev); 5534 else 5535 list_for_each_entry_safe(skb, next, head, list) { 5536 skb_list_del_init(skb); 5537 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5538 } 5539 } 5540 5541 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5542 { 5543 /* Fast-path assumptions: 5544 * - There is no RX handler. 5545 * - Only one packet_type matches. 5546 * If either of these fails, we will end up doing some per-packet 5547 * processing in-line, then handling the 'last ptype' for the whole 5548 * sublist. This can't cause out-of-order delivery to any single ptype, 5549 * because the 'last ptype' must be constant across the sublist, and all 5550 * other ptypes are handled per-packet. 5551 */ 5552 /* Current (common) ptype of sublist */ 5553 struct packet_type *pt_curr = NULL; 5554 /* Current (common) orig_dev of sublist */ 5555 struct net_device *od_curr = NULL; 5556 struct list_head sublist; 5557 struct sk_buff *skb, *next; 5558 5559 INIT_LIST_HEAD(&sublist); 5560 list_for_each_entry_safe(skb, next, head, list) { 5561 struct net_device *orig_dev = skb->dev; 5562 struct packet_type *pt_prev = NULL; 5563 5564 skb_list_del_init(skb); 5565 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5566 if (!pt_prev) 5567 continue; 5568 if (pt_curr != pt_prev || od_curr != orig_dev) { 5569 /* dispatch old sublist */ 5570 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5571 /* start new sublist */ 5572 INIT_LIST_HEAD(&sublist); 5573 pt_curr = pt_prev; 5574 od_curr = orig_dev; 5575 } 5576 list_add_tail(&skb->list, &sublist); 5577 } 5578 5579 /* dispatch final sublist */ 5580 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5581 } 5582 5583 static int __netif_receive_skb(struct sk_buff *skb) 5584 { 5585 int ret; 5586 5587 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5588 unsigned int noreclaim_flag; 5589 5590 /* 5591 * PFMEMALLOC skbs are special, they should 5592 * - be delivered to SOCK_MEMALLOC sockets only 5593 * - stay away from userspace 5594 * - have bounded memory usage 5595 * 5596 * Use PF_MEMALLOC as this saves us from propagating the allocation 5597 * context down to all allocation sites. 5598 */ 5599 noreclaim_flag = memalloc_noreclaim_save(); 5600 ret = __netif_receive_skb_one_core(skb, true); 5601 memalloc_noreclaim_restore(noreclaim_flag); 5602 } else 5603 ret = __netif_receive_skb_one_core(skb, false); 5604 5605 return ret; 5606 } 5607 5608 static void __netif_receive_skb_list(struct list_head *head) 5609 { 5610 unsigned long noreclaim_flag = 0; 5611 struct sk_buff *skb, *next; 5612 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5613 5614 list_for_each_entry_safe(skb, next, head, list) { 5615 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5616 struct list_head sublist; 5617 5618 /* Handle the previous sublist */ 5619 list_cut_before(&sublist, head, &skb->list); 5620 if (!list_empty(&sublist)) 5621 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5622 pfmemalloc = !pfmemalloc; 5623 /* See comments in __netif_receive_skb */ 5624 if (pfmemalloc) 5625 noreclaim_flag = memalloc_noreclaim_save(); 5626 else 5627 memalloc_noreclaim_restore(noreclaim_flag); 5628 } 5629 } 5630 /* Handle the remaining sublist */ 5631 if (!list_empty(head)) 5632 __netif_receive_skb_list_core(head, pfmemalloc); 5633 /* Restore pflags */ 5634 if (pfmemalloc) 5635 memalloc_noreclaim_restore(noreclaim_flag); 5636 } 5637 5638 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5639 { 5640 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5641 struct bpf_prog *new = xdp->prog; 5642 int ret = 0; 5643 5644 switch (xdp->command) { 5645 case XDP_SETUP_PROG: 5646 rcu_assign_pointer(dev->xdp_prog, new); 5647 if (old) 5648 bpf_prog_put(old); 5649 5650 if (old && !new) { 5651 static_branch_dec(&generic_xdp_needed_key); 5652 } else if (new && !old) { 5653 static_branch_inc(&generic_xdp_needed_key); 5654 dev_disable_lro(dev); 5655 dev_disable_gro_hw(dev); 5656 } 5657 break; 5658 5659 default: 5660 ret = -EINVAL; 5661 break; 5662 } 5663 5664 return ret; 5665 } 5666 5667 static int netif_receive_skb_internal(struct sk_buff *skb) 5668 { 5669 int ret; 5670 5671 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5672 5673 if (skb_defer_rx_timestamp(skb)) 5674 return NET_RX_SUCCESS; 5675 5676 rcu_read_lock(); 5677 #ifdef CONFIG_RPS 5678 if (static_branch_unlikely(&rps_needed)) { 5679 struct rps_dev_flow voidflow, *rflow = &voidflow; 5680 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5681 5682 if (cpu >= 0) { 5683 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5684 rcu_read_unlock(); 5685 return ret; 5686 } 5687 } 5688 #endif 5689 ret = __netif_receive_skb(skb); 5690 rcu_read_unlock(); 5691 return ret; 5692 } 5693 5694 void netif_receive_skb_list_internal(struct list_head *head) 5695 { 5696 struct sk_buff *skb, *next; 5697 struct list_head sublist; 5698 5699 INIT_LIST_HEAD(&sublist); 5700 list_for_each_entry_safe(skb, next, head, list) { 5701 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5702 skb_list_del_init(skb); 5703 if (!skb_defer_rx_timestamp(skb)) 5704 list_add_tail(&skb->list, &sublist); 5705 } 5706 list_splice_init(&sublist, head); 5707 5708 rcu_read_lock(); 5709 #ifdef CONFIG_RPS 5710 if (static_branch_unlikely(&rps_needed)) { 5711 list_for_each_entry_safe(skb, next, head, list) { 5712 struct rps_dev_flow voidflow, *rflow = &voidflow; 5713 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5714 5715 if (cpu >= 0) { 5716 /* Will be handled, remove from list */ 5717 skb_list_del_init(skb); 5718 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5719 } 5720 } 5721 } 5722 #endif 5723 __netif_receive_skb_list(head); 5724 rcu_read_unlock(); 5725 } 5726 5727 /** 5728 * netif_receive_skb - process receive buffer from network 5729 * @skb: buffer to process 5730 * 5731 * netif_receive_skb() is the main receive data processing function. 5732 * It always succeeds. The buffer may be dropped during processing 5733 * for congestion control or by the protocol layers. 5734 * 5735 * This function may only be called from softirq context and interrupts 5736 * should be enabled. 5737 * 5738 * Return values (usually ignored): 5739 * NET_RX_SUCCESS: no congestion 5740 * NET_RX_DROP: packet was dropped 5741 */ 5742 int netif_receive_skb(struct sk_buff *skb) 5743 { 5744 int ret; 5745 5746 trace_netif_receive_skb_entry(skb); 5747 5748 ret = netif_receive_skb_internal(skb); 5749 trace_netif_receive_skb_exit(ret); 5750 5751 return ret; 5752 } 5753 EXPORT_SYMBOL(netif_receive_skb); 5754 5755 /** 5756 * netif_receive_skb_list - process many receive buffers from network 5757 * @head: list of skbs to process. 5758 * 5759 * Since return value of netif_receive_skb() is normally ignored, and 5760 * wouldn't be meaningful for a list, this function returns void. 5761 * 5762 * This function may only be called from softirq context and interrupts 5763 * should be enabled. 5764 */ 5765 void netif_receive_skb_list(struct list_head *head) 5766 { 5767 struct sk_buff *skb; 5768 5769 if (list_empty(head)) 5770 return; 5771 if (trace_netif_receive_skb_list_entry_enabled()) { 5772 list_for_each_entry(skb, head, list) 5773 trace_netif_receive_skb_list_entry(skb); 5774 } 5775 netif_receive_skb_list_internal(head); 5776 trace_netif_receive_skb_list_exit(0); 5777 } 5778 EXPORT_SYMBOL(netif_receive_skb_list); 5779 5780 static DEFINE_PER_CPU(struct work_struct, flush_works); 5781 5782 /* Network device is going away, flush any packets still pending */ 5783 static void flush_backlog(struct work_struct *work) 5784 { 5785 struct sk_buff *skb, *tmp; 5786 struct softnet_data *sd; 5787 5788 local_bh_disable(); 5789 sd = this_cpu_ptr(&softnet_data); 5790 5791 rps_lock_irq_disable(sd); 5792 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5793 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5794 __skb_unlink(skb, &sd->input_pkt_queue); 5795 dev_kfree_skb_irq(skb); 5796 input_queue_head_incr(sd); 5797 } 5798 } 5799 rps_unlock_irq_enable(sd); 5800 5801 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5802 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5803 __skb_unlink(skb, &sd->process_queue); 5804 kfree_skb(skb); 5805 input_queue_head_incr(sd); 5806 } 5807 } 5808 local_bh_enable(); 5809 } 5810 5811 static bool flush_required(int cpu) 5812 { 5813 #if IS_ENABLED(CONFIG_RPS) 5814 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5815 bool do_flush; 5816 5817 rps_lock_irq_disable(sd); 5818 5819 /* as insertion into process_queue happens with the rps lock held, 5820 * process_queue access may race only with dequeue 5821 */ 5822 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5823 !skb_queue_empty_lockless(&sd->process_queue); 5824 rps_unlock_irq_enable(sd); 5825 5826 return do_flush; 5827 #endif 5828 /* without RPS we can't safely check input_pkt_queue: during a 5829 * concurrent remote skb_queue_splice() we can detect as empty both 5830 * input_pkt_queue and process_queue even if the latter could end-up 5831 * containing a lot of packets. 5832 */ 5833 return true; 5834 } 5835 5836 static void flush_all_backlogs(void) 5837 { 5838 static cpumask_t flush_cpus; 5839 unsigned int cpu; 5840 5841 /* since we are under rtnl lock protection we can use static data 5842 * for the cpumask and avoid allocating on stack the possibly 5843 * large mask 5844 */ 5845 ASSERT_RTNL(); 5846 5847 cpus_read_lock(); 5848 5849 cpumask_clear(&flush_cpus); 5850 for_each_online_cpu(cpu) { 5851 if (flush_required(cpu)) { 5852 queue_work_on(cpu, system_highpri_wq, 5853 per_cpu_ptr(&flush_works, cpu)); 5854 cpumask_set_cpu(cpu, &flush_cpus); 5855 } 5856 } 5857 5858 /* we can have in flight packet[s] on the cpus we are not flushing, 5859 * synchronize_net() in unregister_netdevice_many() will take care of 5860 * them 5861 */ 5862 for_each_cpu(cpu, &flush_cpus) 5863 flush_work(per_cpu_ptr(&flush_works, cpu)); 5864 5865 cpus_read_unlock(); 5866 } 5867 5868 static void net_rps_send_ipi(struct softnet_data *remsd) 5869 { 5870 #ifdef CONFIG_RPS 5871 while (remsd) { 5872 struct softnet_data *next = remsd->rps_ipi_next; 5873 5874 if (cpu_online(remsd->cpu)) 5875 smp_call_function_single_async(remsd->cpu, &remsd->csd); 5876 remsd = next; 5877 } 5878 #endif 5879 } 5880 5881 /* 5882 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 5883 * Note: called with local irq disabled, but exits with local irq enabled. 5884 */ 5885 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 5886 { 5887 #ifdef CONFIG_RPS 5888 struct softnet_data *remsd = sd->rps_ipi_list; 5889 5890 if (remsd) { 5891 sd->rps_ipi_list = NULL; 5892 5893 local_irq_enable(); 5894 5895 /* Send pending IPI's to kick RPS processing on remote cpus. */ 5896 net_rps_send_ipi(remsd); 5897 } else 5898 #endif 5899 local_irq_enable(); 5900 } 5901 5902 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 5903 { 5904 #ifdef CONFIG_RPS 5905 return sd->rps_ipi_list != NULL; 5906 #else 5907 return false; 5908 #endif 5909 } 5910 5911 static int process_backlog(struct napi_struct *napi, int quota) 5912 { 5913 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 5914 bool again = true; 5915 int work = 0; 5916 5917 /* Check if we have pending ipi, its better to send them now, 5918 * not waiting net_rx_action() end. 5919 */ 5920 if (sd_has_rps_ipi_waiting(sd)) { 5921 local_irq_disable(); 5922 net_rps_action_and_irq_enable(sd); 5923 } 5924 5925 napi->weight = READ_ONCE(dev_rx_weight); 5926 while (again) { 5927 struct sk_buff *skb; 5928 5929 while ((skb = __skb_dequeue(&sd->process_queue))) { 5930 rcu_read_lock(); 5931 __netif_receive_skb(skb); 5932 rcu_read_unlock(); 5933 input_queue_head_incr(sd); 5934 if (++work >= quota) 5935 return work; 5936 5937 } 5938 5939 rps_lock_irq_disable(sd); 5940 if (skb_queue_empty(&sd->input_pkt_queue)) { 5941 /* 5942 * Inline a custom version of __napi_complete(). 5943 * only current cpu owns and manipulates this napi, 5944 * and NAPI_STATE_SCHED is the only possible flag set 5945 * on backlog. 5946 * We can use a plain write instead of clear_bit(), 5947 * and we dont need an smp_mb() memory barrier. 5948 */ 5949 napi->state = 0; 5950 again = false; 5951 } else { 5952 skb_queue_splice_tail_init(&sd->input_pkt_queue, 5953 &sd->process_queue); 5954 } 5955 rps_unlock_irq_enable(sd); 5956 } 5957 5958 return work; 5959 } 5960 5961 /** 5962 * __napi_schedule - schedule for receive 5963 * @n: entry to schedule 5964 * 5965 * The entry's receive function will be scheduled to run. 5966 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 5967 */ 5968 void __napi_schedule(struct napi_struct *n) 5969 { 5970 unsigned long flags; 5971 5972 local_irq_save(flags); 5973 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5974 local_irq_restore(flags); 5975 } 5976 EXPORT_SYMBOL(__napi_schedule); 5977 5978 /** 5979 * napi_schedule_prep - check if napi can be scheduled 5980 * @n: napi context 5981 * 5982 * Test if NAPI routine is already running, and if not mark 5983 * it as running. This is used as a condition variable to 5984 * insure only one NAPI poll instance runs. We also make 5985 * sure there is no pending NAPI disable. 5986 */ 5987 bool napi_schedule_prep(struct napi_struct *n) 5988 { 5989 unsigned long val, new; 5990 5991 do { 5992 val = READ_ONCE(n->state); 5993 if (unlikely(val & NAPIF_STATE_DISABLE)) 5994 return false; 5995 new = val | NAPIF_STATE_SCHED; 5996 5997 /* Sets STATE_MISSED bit if STATE_SCHED was already set 5998 * This was suggested by Alexander Duyck, as compiler 5999 * emits better code than : 6000 * if (val & NAPIF_STATE_SCHED) 6001 * new |= NAPIF_STATE_MISSED; 6002 */ 6003 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6004 NAPIF_STATE_MISSED; 6005 } while (cmpxchg(&n->state, val, new) != val); 6006 6007 return !(val & NAPIF_STATE_SCHED); 6008 } 6009 EXPORT_SYMBOL(napi_schedule_prep); 6010 6011 /** 6012 * __napi_schedule_irqoff - schedule for receive 6013 * @n: entry to schedule 6014 * 6015 * Variant of __napi_schedule() assuming hard irqs are masked. 6016 * 6017 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6018 * because the interrupt disabled assumption might not be true 6019 * due to force-threaded interrupts and spinlock substitution. 6020 */ 6021 void __napi_schedule_irqoff(struct napi_struct *n) 6022 { 6023 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6024 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6025 else 6026 __napi_schedule(n); 6027 } 6028 EXPORT_SYMBOL(__napi_schedule_irqoff); 6029 6030 bool napi_complete_done(struct napi_struct *n, int work_done) 6031 { 6032 unsigned long flags, val, new, timeout = 0; 6033 bool ret = true; 6034 6035 /* 6036 * 1) Don't let napi dequeue from the cpu poll list 6037 * just in case its running on a different cpu. 6038 * 2) If we are busy polling, do nothing here, we have 6039 * the guarantee we will be called later. 6040 */ 6041 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6042 NAPIF_STATE_IN_BUSY_POLL))) 6043 return false; 6044 6045 if (work_done) { 6046 if (n->gro_bitmask) 6047 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6048 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 6049 } 6050 if (n->defer_hard_irqs_count > 0) { 6051 n->defer_hard_irqs_count--; 6052 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6053 if (timeout) 6054 ret = false; 6055 } 6056 if (n->gro_bitmask) { 6057 /* When the NAPI instance uses a timeout and keeps postponing 6058 * it, we need to bound somehow the time packets are kept in 6059 * the GRO layer 6060 */ 6061 napi_gro_flush(n, !!timeout); 6062 } 6063 6064 gro_normal_list(n); 6065 6066 if (unlikely(!list_empty(&n->poll_list))) { 6067 /* If n->poll_list is not empty, we need to mask irqs */ 6068 local_irq_save(flags); 6069 list_del_init(&n->poll_list); 6070 local_irq_restore(flags); 6071 } 6072 6073 do { 6074 val = READ_ONCE(n->state); 6075 6076 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6077 6078 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6079 NAPIF_STATE_SCHED_THREADED | 6080 NAPIF_STATE_PREFER_BUSY_POLL); 6081 6082 /* If STATE_MISSED was set, leave STATE_SCHED set, 6083 * because we will call napi->poll() one more time. 6084 * This C code was suggested by Alexander Duyck to help gcc. 6085 */ 6086 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6087 NAPIF_STATE_SCHED; 6088 } while (cmpxchg(&n->state, val, new) != val); 6089 6090 if (unlikely(val & NAPIF_STATE_MISSED)) { 6091 __napi_schedule(n); 6092 return false; 6093 } 6094 6095 if (timeout) 6096 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6097 HRTIMER_MODE_REL_PINNED); 6098 return ret; 6099 } 6100 EXPORT_SYMBOL(napi_complete_done); 6101 6102 /* must be called under rcu_read_lock(), as we dont take a reference */ 6103 static struct napi_struct *napi_by_id(unsigned int napi_id) 6104 { 6105 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 6106 struct napi_struct *napi; 6107 6108 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 6109 if (napi->napi_id == napi_id) 6110 return napi; 6111 6112 return NULL; 6113 } 6114 6115 #if defined(CONFIG_NET_RX_BUSY_POLL) 6116 6117 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6118 { 6119 if (!skip_schedule) { 6120 gro_normal_list(napi); 6121 __napi_schedule(napi); 6122 return; 6123 } 6124 6125 if (napi->gro_bitmask) { 6126 /* flush too old packets 6127 * If HZ < 1000, flush all packets. 6128 */ 6129 napi_gro_flush(napi, HZ >= 1000); 6130 } 6131 6132 gro_normal_list(napi); 6133 clear_bit(NAPI_STATE_SCHED, &napi->state); 6134 } 6135 6136 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll, 6137 u16 budget) 6138 { 6139 bool skip_schedule = false; 6140 unsigned long timeout; 6141 int rc; 6142 6143 /* Busy polling means there is a high chance device driver hard irq 6144 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6145 * set in napi_schedule_prep(). 6146 * Since we are about to call napi->poll() once more, we can safely 6147 * clear NAPI_STATE_MISSED. 6148 * 6149 * Note: x86 could use a single "lock and ..." instruction 6150 * to perform these two clear_bit() 6151 */ 6152 clear_bit(NAPI_STATE_MISSED, &napi->state); 6153 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6154 6155 local_bh_disable(); 6156 6157 if (prefer_busy_poll) { 6158 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6159 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6160 if (napi->defer_hard_irqs_count && timeout) { 6161 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6162 skip_schedule = true; 6163 } 6164 } 6165 6166 /* All we really want here is to re-enable device interrupts. 6167 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6168 */ 6169 rc = napi->poll(napi, budget); 6170 /* We can't gro_normal_list() here, because napi->poll() might have 6171 * rearmed the napi (napi_complete_done()) in which case it could 6172 * already be running on another CPU. 6173 */ 6174 trace_napi_poll(napi, rc, budget); 6175 netpoll_poll_unlock(have_poll_lock); 6176 if (rc == budget) 6177 __busy_poll_stop(napi, skip_schedule); 6178 local_bh_enable(); 6179 } 6180 6181 void napi_busy_loop(unsigned int napi_id, 6182 bool (*loop_end)(void *, unsigned long), 6183 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6184 { 6185 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6186 int (*napi_poll)(struct napi_struct *napi, int budget); 6187 void *have_poll_lock = NULL; 6188 struct napi_struct *napi; 6189 6190 restart: 6191 napi_poll = NULL; 6192 6193 rcu_read_lock(); 6194 6195 napi = napi_by_id(napi_id); 6196 if (!napi) 6197 goto out; 6198 6199 preempt_disable(); 6200 for (;;) { 6201 int work = 0; 6202 6203 local_bh_disable(); 6204 if (!napi_poll) { 6205 unsigned long val = READ_ONCE(napi->state); 6206 6207 /* If multiple threads are competing for this napi, 6208 * we avoid dirtying napi->state as much as we can. 6209 */ 6210 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6211 NAPIF_STATE_IN_BUSY_POLL)) { 6212 if (prefer_busy_poll) 6213 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6214 goto count; 6215 } 6216 if (cmpxchg(&napi->state, val, 6217 val | NAPIF_STATE_IN_BUSY_POLL | 6218 NAPIF_STATE_SCHED) != val) { 6219 if (prefer_busy_poll) 6220 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6221 goto count; 6222 } 6223 have_poll_lock = netpoll_poll_lock(napi); 6224 napi_poll = napi->poll; 6225 } 6226 work = napi_poll(napi, budget); 6227 trace_napi_poll(napi, work, budget); 6228 gro_normal_list(napi); 6229 count: 6230 if (work > 0) 6231 __NET_ADD_STATS(dev_net(napi->dev), 6232 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6233 local_bh_enable(); 6234 6235 if (!loop_end || loop_end(loop_end_arg, start_time)) 6236 break; 6237 6238 if (unlikely(need_resched())) { 6239 if (napi_poll) 6240 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6241 preempt_enable(); 6242 rcu_read_unlock(); 6243 cond_resched(); 6244 if (loop_end(loop_end_arg, start_time)) 6245 return; 6246 goto restart; 6247 } 6248 cpu_relax(); 6249 } 6250 if (napi_poll) 6251 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6252 preempt_enable(); 6253 out: 6254 rcu_read_unlock(); 6255 } 6256 EXPORT_SYMBOL(napi_busy_loop); 6257 6258 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6259 6260 static void napi_hash_add(struct napi_struct *napi) 6261 { 6262 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6263 return; 6264 6265 spin_lock(&napi_hash_lock); 6266 6267 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6268 do { 6269 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6270 napi_gen_id = MIN_NAPI_ID; 6271 } while (napi_by_id(napi_gen_id)); 6272 napi->napi_id = napi_gen_id; 6273 6274 hlist_add_head_rcu(&napi->napi_hash_node, 6275 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6276 6277 spin_unlock(&napi_hash_lock); 6278 } 6279 6280 /* Warning : caller is responsible to make sure rcu grace period 6281 * is respected before freeing memory containing @napi 6282 */ 6283 static void napi_hash_del(struct napi_struct *napi) 6284 { 6285 spin_lock(&napi_hash_lock); 6286 6287 hlist_del_init_rcu(&napi->napi_hash_node); 6288 6289 spin_unlock(&napi_hash_lock); 6290 } 6291 6292 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6293 { 6294 struct napi_struct *napi; 6295 6296 napi = container_of(timer, struct napi_struct, timer); 6297 6298 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6299 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6300 */ 6301 if (!napi_disable_pending(napi) && 6302 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6303 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6304 __napi_schedule_irqoff(napi); 6305 } 6306 6307 return HRTIMER_NORESTART; 6308 } 6309 6310 static void init_gro_hash(struct napi_struct *napi) 6311 { 6312 int i; 6313 6314 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6315 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6316 napi->gro_hash[i].count = 0; 6317 } 6318 napi->gro_bitmask = 0; 6319 } 6320 6321 int dev_set_threaded(struct net_device *dev, bool threaded) 6322 { 6323 struct napi_struct *napi; 6324 int err = 0; 6325 6326 if (dev->threaded == threaded) 6327 return 0; 6328 6329 if (threaded) { 6330 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6331 if (!napi->thread) { 6332 err = napi_kthread_create(napi); 6333 if (err) { 6334 threaded = false; 6335 break; 6336 } 6337 } 6338 } 6339 } 6340 6341 dev->threaded = threaded; 6342 6343 /* Make sure kthread is created before THREADED bit 6344 * is set. 6345 */ 6346 smp_mb__before_atomic(); 6347 6348 /* Setting/unsetting threaded mode on a napi might not immediately 6349 * take effect, if the current napi instance is actively being 6350 * polled. In this case, the switch between threaded mode and 6351 * softirq mode will happen in the next round of napi_schedule(). 6352 * This should not cause hiccups/stalls to the live traffic. 6353 */ 6354 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6355 if (threaded) 6356 set_bit(NAPI_STATE_THREADED, &napi->state); 6357 else 6358 clear_bit(NAPI_STATE_THREADED, &napi->state); 6359 } 6360 6361 return err; 6362 } 6363 EXPORT_SYMBOL(dev_set_threaded); 6364 6365 void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, 6366 int (*poll)(struct napi_struct *, int), int weight) 6367 { 6368 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6369 return; 6370 6371 INIT_LIST_HEAD(&napi->poll_list); 6372 INIT_HLIST_NODE(&napi->napi_hash_node); 6373 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6374 napi->timer.function = napi_watchdog; 6375 init_gro_hash(napi); 6376 napi->skb = NULL; 6377 INIT_LIST_HEAD(&napi->rx_list); 6378 napi->rx_count = 0; 6379 napi->poll = poll; 6380 if (weight > NAPI_POLL_WEIGHT) 6381 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6382 weight); 6383 napi->weight = weight; 6384 napi->dev = dev; 6385 #ifdef CONFIG_NETPOLL 6386 napi->poll_owner = -1; 6387 #endif 6388 set_bit(NAPI_STATE_SCHED, &napi->state); 6389 set_bit(NAPI_STATE_NPSVC, &napi->state); 6390 list_add_rcu(&napi->dev_list, &dev->napi_list); 6391 napi_hash_add(napi); 6392 napi_get_frags_check(napi); 6393 /* Create kthread for this napi if dev->threaded is set. 6394 * Clear dev->threaded if kthread creation failed so that 6395 * threaded mode will not be enabled in napi_enable(). 6396 */ 6397 if (dev->threaded && napi_kthread_create(napi)) 6398 dev->threaded = 0; 6399 } 6400 EXPORT_SYMBOL(netif_napi_add_weight); 6401 6402 void napi_disable(struct napi_struct *n) 6403 { 6404 unsigned long val, new; 6405 6406 might_sleep(); 6407 set_bit(NAPI_STATE_DISABLE, &n->state); 6408 6409 for ( ; ; ) { 6410 val = READ_ONCE(n->state); 6411 if (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6412 usleep_range(20, 200); 6413 continue; 6414 } 6415 6416 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6417 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6418 6419 if (cmpxchg(&n->state, val, new) == val) 6420 break; 6421 } 6422 6423 hrtimer_cancel(&n->timer); 6424 6425 clear_bit(NAPI_STATE_DISABLE, &n->state); 6426 } 6427 EXPORT_SYMBOL(napi_disable); 6428 6429 /** 6430 * napi_enable - enable NAPI scheduling 6431 * @n: NAPI context 6432 * 6433 * Resume NAPI from being scheduled on this context. 6434 * Must be paired with napi_disable. 6435 */ 6436 void napi_enable(struct napi_struct *n) 6437 { 6438 unsigned long val, new; 6439 6440 do { 6441 val = READ_ONCE(n->state); 6442 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6443 6444 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6445 if (n->dev->threaded && n->thread) 6446 new |= NAPIF_STATE_THREADED; 6447 } while (cmpxchg(&n->state, val, new) != val); 6448 } 6449 EXPORT_SYMBOL(napi_enable); 6450 6451 static void flush_gro_hash(struct napi_struct *napi) 6452 { 6453 int i; 6454 6455 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6456 struct sk_buff *skb, *n; 6457 6458 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6459 kfree_skb(skb); 6460 napi->gro_hash[i].count = 0; 6461 } 6462 } 6463 6464 /* Must be called in process context */ 6465 void __netif_napi_del(struct napi_struct *napi) 6466 { 6467 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6468 return; 6469 6470 napi_hash_del(napi); 6471 list_del_rcu(&napi->dev_list); 6472 napi_free_frags(napi); 6473 6474 flush_gro_hash(napi); 6475 napi->gro_bitmask = 0; 6476 6477 if (napi->thread) { 6478 kthread_stop(napi->thread); 6479 napi->thread = NULL; 6480 } 6481 } 6482 EXPORT_SYMBOL(__netif_napi_del); 6483 6484 static int __napi_poll(struct napi_struct *n, bool *repoll) 6485 { 6486 int work, weight; 6487 6488 weight = n->weight; 6489 6490 /* This NAPI_STATE_SCHED test is for avoiding a race 6491 * with netpoll's poll_napi(). Only the entity which 6492 * obtains the lock and sees NAPI_STATE_SCHED set will 6493 * actually make the ->poll() call. Therefore we avoid 6494 * accidentally calling ->poll() when NAPI is not scheduled. 6495 */ 6496 work = 0; 6497 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 6498 work = n->poll(n, weight); 6499 trace_napi_poll(n, work, weight); 6500 } 6501 6502 if (unlikely(work > weight)) 6503 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6504 n->poll, work, weight); 6505 6506 if (likely(work < weight)) 6507 return work; 6508 6509 /* Drivers must not modify the NAPI state if they 6510 * consume the entire weight. In such cases this code 6511 * still "owns" the NAPI instance and therefore can 6512 * move the instance around on the list at-will. 6513 */ 6514 if (unlikely(napi_disable_pending(n))) { 6515 napi_complete(n); 6516 return work; 6517 } 6518 6519 /* The NAPI context has more processing work, but busy-polling 6520 * is preferred. Exit early. 6521 */ 6522 if (napi_prefer_busy_poll(n)) { 6523 if (napi_complete_done(n, work)) { 6524 /* If timeout is not set, we need to make sure 6525 * that the NAPI is re-scheduled. 6526 */ 6527 napi_schedule(n); 6528 } 6529 return work; 6530 } 6531 6532 if (n->gro_bitmask) { 6533 /* flush too old packets 6534 * If HZ < 1000, flush all packets. 6535 */ 6536 napi_gro_flush(n, HZ >= 1000); 6537 } 6538 6539 gro_normal_list(n); 6540 6541 /* Some drivers may have called napi_schedule 6542 * prior to exhausting their budget. 6543 */ 6544 if (unlikely(!list_empty(&n->poll_list))) { 6545 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6546 n->dev ? n->dev->name : "backlog"); 6547 return work; 6548 } 6549 6550 *repoll = true; 6551 6552 return work; 6553 } 6554 6555 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6556 { 6557 bool do_repoll = false; 6558 void *have; 6559 int work; 6560 6561 list_del_init(&n->poll_list); 6562 6563 have = netpoll_poll_lock(n); 6564 6565 work = __napi_poll(n, &do_repoll); 6566 6567 if (do_repoll) 6568 list_add_tail(&n->poll_list, repoll); 6569 6570 netpoll_poll_unlock(have); 6571 6572 return work; 6573 } 6574 6575 static int napi_thread_wait(struct napi_struct *napi) 6576 { 6577 bool woken = false; 6578 6579 set_current_state(TASK_INTERRUPTIBLE); 6580 6581 while (!kthread_should_stop()) { 6582 /* Testing SCHED_THREADED bit here to make sure the current 6583 * kthread owns this napi and could poll on this napi. 6584 * Testing SCHED bit is not enough because SCHED bit might be 6585 * set by some other busy poll thread or by napi_disable(). 6586 */ 6587 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) { 6588 WARN_ON(!list_empty(&napi->poll_list)); 6589 __set_current_state(TASK_RUNNING); 6590 return 0; 6591 } 6592 6593 schedule(); 6594 /* woken being true indicates this thread owns this napi. */ 6595 woken = true; 6596 set_current_state(TASK_INTERRUPTIBLE); 6597 } 6598 __set_current_state(TASK_RUNNING); 6599 6600 return -1; 6601 } 6602 6603 static int napi_threaded_poll(void *data) 6604 { 6605 struct napi_struct *napi = data; 6606 void *have; 6607 6608 while (!napi_thread_wait(napi)) { 6609 for (;;) { 6610 bool repoll = false; 6611 6612 local_bh_disable(); 6613 6614 have = netpoll_poll_lock(napi); 6615 __napi_poll(napi, &repoll); 6616 netpoll_poll_unlock(have); 6617 6618 local_bh_enable(); 6619 6620 if (!repoll) 6621 break; 6622 6623 cond_resched(); 6624 } 6625 } 6626 return 0; 6627 } 6628 6629 static void skb_defer_free_flush(struct softnet_data *sd) 6630 { 6631 struct sk_buff *skb, *next; 6632 unsigned long flags; 6633 6634 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6635 if (!READ_ONCE(sd->defer_list)) 6636 return; 6637 6638 spin_lock_irqsave(&sd->defer_lock, flags); 6639 skb = sd->defer_list; 6640 sd->defer_list = NULL; 6641 sd->defer_count = 0; 6642 spin_unlock_irqrestore(&sd->defer_lock, flags); 6643 6644 while (skb != NULL) { 6645 next = skb->next; 6646 napi_consume_skb(skb, 1); 6647 skb = next; 6648 } 6649 } 6650 6651 static __latent_entropy void net_rx_action(struct softirq_action *h) 6652 { 6653 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6654 unsigned long time_limit = jiffies + 6655 usecs_to_jiffies(READ_ONCE(netdev_budget_usecs)); 6656 int budget = READ_ONCE(netdev_budget); 6657 LIST_HEAD(list); 6658 LIST_HEAD(repoll); 6659 6660 local_irq_disable(); 6661 list_splice_init(&sd->poll_list, &list); 6662 local_irq_enable(); 6663 6664 for (;;) { 6665 struct napi_struct *n; 6666 6667 skb_defer_free_flush(sd); 6668 6669 if (list_empty(&list)) { 6670 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll)) 6671 goto end; 6672 break; 6673 } 6674 6675 n = list_first_entry(&list, struct napi_struct, poll_list); 6676 budget -= napi_poll(n, &repoll); 6677 6678 /* If softirq window is exhausted then punt. 6679 * Allow this to run for 2 jiffies since which will allow 6680 * an average latency of 1.5/HZ. 6681 */ 6682 if (unlikely(budget <= 0 || 6683 time_after_eq(jiffies, time_limit))) { 6684 sd->time_squeeze++; 6685 break; 6686 } 6687 } 6688 6689 local_irq_disable(); 6690 6691 list_splice_tail_init(&sd->poll_list, &list); 6692 list_splice_tail(&repoll, &list); 6693 list_splice(&list, &sd->poll_list); 6694 if (!list_empty(&sd->poll_list)) 6695 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6696 6697 net_rps_action_and_irq_enable(sd); 6698 end:; 6699 } 6700 6701 struct netdev_adjacent { 6702 struct net_device *dev; 6703 netdevice_tracker dev_tracker; 6704 6705 /* upper master flag, there can only be one master device per list */ 6706 bool master; 6707 6708 /* lookup ignore flag */ 6709 bool ignore; 6710 6711 /* counter for the number of times this device was added to us */ 6712 u16 ref_nr; 6713 6714 /* private field for the users */ 6715 void *private; 6716 6717 struct list_head list; 6718 struct rcu_head rcu; 6719 }; 6720 6721 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6722 struct list_head *adj_list) 6723 { 6724 struct netdev_adjacent *adj; 6725 6726 list_for_each_entry(adj, adj_list, list) { 6727 if (adj->dev == adj_dev) 6728 return adj; 6729 } 6730 return NULL; 6731 } 6732 6733 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6734 struct netdev_nested_priv *priv) 6735 { 6736 struct net_device *dev = (struct net_device *)priv->data; 6737 6738 return upper_dev == dev; 6739 } 6740 6741 /** 6742 * netdev_has_upper_dev - Check if device is linked to an upper device 6743 * @dev: device 6744 * @upper_dev: upper device to check 6745 * 6746 * Find out if a device is linked to specified upper device and return true 6747 * in case it is. Note that this checks only immediate upper device, 6748 * not through a complete stack of devices. The caller must hold the RTNL lock. 6749 */ 6750 bool netdev_has_upper_dev(struct net_device *dev, 6751 struct net_device *upper_dev) 6752 { 6753 struct netdev_nested_priv priv = { 6754 .data = (void *)upper_dev, 6755 }; 6756 6757 ASSERT_RTNL(); 6758 6759 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6760 &priv); 6761 } 6762 EXPORT_SYMBOL(netdev_has_upper_dev); 6763 6764 /** 6765 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6766 * @dev: device 6767 * @upper_dev: upper device to check 6768 * 6769 * Find out if a device is linked to specified upper device and return true 6770 * in case it is. Note that this checks the entire upper device chain. 6771 * The caller must hold rcu lock. 6772 */ 6773 6774 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 6775 struct net_device *upper_dev) 6776 { 6777 struct netdev_nested_priv priv = { 6778 .data = (void *)upper_dev, 6779 }; 6780 6781 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6782 &priv); 6783 } 6784 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 6785 6786 /** 6787 * netdev_has_any_upper_dev - Check if device is linked to some device 6788 * @dev: device 6789 * 6790 * Find out if a device is linked to an upper device and return true in case 6791 * it is. The caller must hold the RTNL lock. 6792 */ 6793 bool netdev_has_any_upper_dev(struct net_device *dev) 6794 { 6795 ASSERT_RTNL(); 6796 6797 return !list_empty(&dev->adj_list.upper); 6798 } 6799 EXPORT_SYMBOL(netdev_has_any_upper_dev); 6800 6801 /** 6802 * netdev_master_upper_dev_get - Get master upper device 6803 * @dev: device 6804 * 6805 * Find a master upper device and return pointer to it or NULL in case 6806 * it's not there. The caller must hold the RTNL lock. 6807 */ 6808 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 6809 { 6810 struct netdev_adjacent *upper; 6811 6812 ASSERT_RTNL(); 6813 6814 if (list_empty(&dev->adj_list.upper)) 6815 return NULL; 6816 6817 upper = list_first_entry(&dev->adj_list.upper, 6818 struct netdev_adjacent, list); 6819 if (likely(upper->master)) 6820 return upper->dev; 6821 return NULL; 6822 } 6823 EXPORT_SYMBOL(netdev_master_upper_dev_get); 6824 6825 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 6826 { 6827 struct netdev_adjacent *upper; 6828 6829 ASSERT_RTNL(); 6830 6831 if (list_empty(&dev->adj_list.upper)) 6832 return NULL; 6833 6834 upper = list_first_entry(&dev->adj_list.upper, 6835 struct netdev_adjacent, list); 6836 if (likely(upper->master) && !upper->ignore) 6837 return upper->dev; 6838 return NULL; 6839 } 6840 6841 /** 6842 * netdev_has_any_lower_dev - Check if device is linked to some device 6843 * @dev: device 6844 * 6845 * Find out if a device is linked to a lower device and return true in case 6846 * it is. The caller must hold the RTNL lock. 6847 */ 6848 static bool netdev_has_any_lower_dev(struct net_device *dev) 6849 { 6850 ASSERT_RTNL(); 6851 6852 return !list_empty(&dev->adj_list.lower); 6853 } 6854 6855 void *netdev_adjacent_get_private(struct list_head *adj_list) 6856 { 6857 struct netdev_adjacent *adj; 6858 6859 adj = list_entry(adj_list, struct netdev_adjacent, list); 6860 6861 return adj->private; 6862 } 6863 EXPORT_SYMBOL(netdev_adjacent_get_private); 6864 6865 /** 6866 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 6867 * @dev: device 6868 * @iter: list_head ** of the current position 6869 * 6870 * Gets the next device from the dev's upper list, starting from iter 6871 * position. The caller must hold RCU read lock. 6872 */ 6873 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 6874 struct list_head **iter) 6875 { 6876 struct netdev_adjacent *upper; 6877 6878 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6879 6880 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6881 6882 if (&upper->list == &dev->adj_list.upper) 6883 return NULL; 6884 6885 *iter = &upper->list; 6886 6887 return upper->dev; 6888 } 6889 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 6890 6891 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 6892 struct list_head **iter, 6893 bool *ignore) 6894 { 6895 struct netdev_adjacent *upper; 6896 6897 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 6898 6899 if (&upper->list == &dev->adj_list.upper) 6900 return NULL; 6901 6902 *iter = &upper->list; 6903 *ignore = upper->ignore; 6904 6905 return upper->dev; 6906 } 6907 6908 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 6909 struct list_head **iter) 6910 { 6911 struct netdev_adjacent *upper; 6912 6913 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6914 6915 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6916 6917 if (&upper->list == &dev->adj_list.upper) 6918 return NULL; 6919 6920 *iter = &upper->list; 6921 6922 return upper->dev; 6923 } 6924 6925 static int __netdev_walk_all_upper_dev(struct net_device *dev, 6926 int (*fn)(struct net_device *dev, 6927 struct netdev_nested_priv *priv), 6928 struct netdev_nested_priv *priv) 6929 { 6930 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6931 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6932 int ret, cur = 0; 6933 bool ignore; 6934 6935 now = dev; 6936 iter = &dev->adj_list.upper; 6937 6938 while (1) { 6939 if (now != dev) { 6940 ret = fn(now, priv); 6941 if (ret) 6942 return ret; 6943 } 6944 6945 next = NULL; 6946 while (1) { 6947 udev = __netdev_next_upper_dev(now, &iter, &ignore); 6948 if (!udev) 6949 break; 6950 if (ignore) 6951 continue; 6952 6953 next = udev; 6954 niter = &udev->adj_list.upper; 6955 dev_stack[cur] = now; 6956 iter_stack[cur++] = iter; 6957 break; 6958 } 6959 6960 if (!next) { 6961 if (!cur) 6962 return 0; 6963 next = dev_stack[--cur]; 6964 niter = iter_stack[cur]; 6965 } 6966 6967 now = next; 6968 iter = niter; 6969 } 6970 6971 return 0; 6972 } 6973 6974 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 6975 int (*fn)(struct net_device *dev, 6976 struct netdev_nested_priv *priv), 6977 struct netdev_nested_priv *priv) 6978 { 6979 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6980 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6981 int ret, cur = 0; 6982 6983 now = dev; 6984 iter = &dev->adj_list.upper; 6985 6986 while (1) { 6987 if (now != dev) { 6988 ret = fn(now, priv); 6989 if (ret) 6990 return ret; 6991 } 6992 6993 next = NULL; 6994 while (1) { 6995 udev = netdev_next_upper_dev_rcu(now, &iter); 6996 if (!udev) 6997 break; 6998 6999 next = udev; 7000 niter = &udev->adj_list.upper; 7001 dev_stack[cur] = now; 7002 iter_stack[cur++] = iter; 7003 break; 7004 } 7005 7006 if (!next) { 7007 if (!cur) 7008 return 0; 7009 next = dev_stack[--cur]; 7010 niter = iter_stack[cur]; 7011 } 7012 7013 now = next; 7014 iter = niter; 7015 } 7016 7017 return 0; 7018 } 7019 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 7020 7021 static bool __netdev_has_upper_dev(struct net_device *dev, 7022 struct net_device *upper_dev) 7023 { 7024 struct netdev_nested_priv priv = { 7025 .flags = 0, 7026 .data = (void *)upper_dev, 7027 }; 7028 7029 ASSERT_RTNL(); 7030 7031 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 7032 &priv); 7033 } 7034 7035 /** 7036 * netdev_lower_get_next_private - Get the next ->private from the 7037 * lower neighbour list 7038 * @dev: device 7039 * @iter: list_head ** of the current position 7040 * 7041 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7042 * list, starting from iter position. The caller must hold either hold the 7043 * RTNL lock or its own locking that guarantees that the neighbour lower 7044 * list will remain unchanged. 7045 */ 7046 void *netdev_lower_get_next_private(struct net_device *dev, 7047 struct list_head **iter) 7048 { 7049 struct netdev_adjacent *lower; 7050 7051 lower = list_entry(*iter, struct netdev_adjacent, list); 7052 7053 if (&lower->list == &dev->adj_list.lower) 7054 return NULL; 7055 7056 *iter = lower->list.next; 7057 7058 return lower->private; 7059 } 7060 EXPORT_SYMBOL(netdev_lower_get_next_private); 7061 7062 /** 7063 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7064 * lower neighbour list, RCU 7065 * variant 7066 * @dev: device 7067 * @iter: list_head ** of the current position 7068 * 7069 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7070 * list, starting from iter position. The caller must hold RCU read lock. 7071 */ 7072 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7073 struct list_head **iter) 7074 { 7075 struct netdev_adjacent *lower; 7076 7077 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7078 7079 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7080 7081 if (&lower->list == &dev->adj_list.lower) 7082 return NULL; 7083 7084 *iter = &lower->list; 7085 7086 return lower->private; 7087 } 7088 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7089 7090 /** 7091 * netdev_lower_get_next - Get the next device from the lower neighbour 7092 * list 7093 * @dev: device 7094 * @iter: list_head ** of the current position 7095 * 7096 * Gets the next netdev_adjacent from the dev's lower neighbour 7097 * list, starting from iter position. The caller must hold RTNL lock or 7098 * its own locking that guarantees that the neighbour lower 7099 * list will remain unchanged. 7100 */ 7101 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7102 { 7103 struct netdev_adjacent *lower; 7104 7105 lower = list_entry(*iter, struct netdev_adjacent, list); 7106 7107 if (&lower->list == &dev->adj_list.lower) 7108 return NULL; 7109 7110 *iter = lower->list.next; 7111 7112 return lower->dev; 7113 } 7114 EXPORT_SYMBOL(netdev_lower_get_next); 7115 7116 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7117 struct list_head **iter) 7118 { 7119 struct netdev_adjacent *lower; 7120 7121 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7122 7123 if (&lower->list == &dev->adj_list.lower) 7124 return NULL; 7125 7126 *iter = &lower->list; 7127 7128 return lower->dev; 7129 } 7130 7131 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7132 struct list_head **iter, 7133 bool *ignore) 7134 { 7135 struct netdev_adjacent *lower; 7136 7137 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7138 7139 if (&lower->list == &dev->adj_list.lower) 7140 return NULL; 7141 7142 *iter = &lower->list; 7143 *ignore = lower->ignore; 7144 7145 return lower->dev; 7146 } 7147 7148 int netdev_walk_all_lower_dev(struct net_device *dev, 7149 int (*fn)(struct net_device *dev, 7150 struct netdev_nested_priv *priv), 7151 struct netdev_nested_priv *priv) 7152 { 7153 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7154 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7155 int ret, cur = 0; 7156 7157 now = dev; 7158 iter = &dev->adj_list.lower; 7159 7160 while (1) { 7161 if (now != dev) { 7162 ret = fn(now, priv); 7163 if (ret) 7164 return ret; 7165 } 7166 7167 next = NULL; 7168 while (1) { 7169 ldev = netdev_next_lower_dev(now, &iter); 7170 if (!ldev) 7171 break; 7172 7173 next = ldev; 7174 niter = &ldev->adj_list.lower; 7175 dev_stack[cur] = now; 7176 iter_stack[cur++] = iter; 7177 break; 7178 } 7179 7180 if (!next) { 7181 if (!cur) 7182 return 0; 7183 next = dev_stack[--cur]; 7184 niter = iter_stack[cur]; 7185 } 7186 7187 now = next; 7188 iter = niter; 7189 } 7190 7191 return 0; 7192 } 7193 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7194 7195 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7196 int (*fn)(struct net_device *dev, 7197 struct netdev_nested_priv *priv), 7198 struct netdev_nested_priv *priv) 7199 { 7200 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7201 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7202 int ret, cur = 0; 7203 bool ignore; 7204 7205 now = dev; 7206 iter = &dev->adj_list.lower; 7207 7208 while (1) { 7209 if (now != dev) { 7210 ret = fn(now, priv); 7211 if (ret) 7212 return ret; 7213 } 7214 7215 next = NULL; 7216 while (1) { 7217 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7218 if (!ldev) 7219 break; 7220 if (ignore) 7221 continue; 7222 7223 next = ldev; 7224 niter = &ldev->adj_list.lower; 7225 dev_stack[cur] = now; 7226 iter_stack[cur++] = iter; 7227 break; 7228 } 7229 7230 if (!next) { 7231 if (!cur) 7232 return 0; 7233 next = dev_stack[--cur]; 7234 niter = iter_stack[cur]; 7235 } 7236 7237 now = next; 7238 iter = niter; 7239 } 7240 7241 return 0; 7242 } 7243 7244 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7245 struct list_head **iter) 7246 { 7247 struct netdev_adjacent *lower; 7248 7249 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7250 if (&lower->list == &dev->adj_list.lower) 7251 return NULL; 7252 7253 *iter = &lower->list; 7254 7255 return lower->dev; 7256 } 7257 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7258 7259 static u8 __netdev_upper_depth(struct net_device *dev) 7260 { 7261 struct net_device *udev; 7262 struct list_head *iter; 7263 u8 max_depth = 0; 7264 bool ignore; 7265 7266 for (iter = &dev->adj_list.upper, 7267 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7268 udev; 7269 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7270 if (ignore) 7271 continue; 7272 if (max_depth < udev->upper_level) 7273 max_depth = udev->upper_level; 7274 } 7275 7276 return max_depth; 7277 } 7278 7279 static u8 __netdev_lower_depth(struct net_device *dev) 7280 { 7281 struct net_device *ldev; 7282 struct list_head *iter; 7283 u8 max_depth = 0; 7284 bool ignore; 7285 7286 for (iter = &dev->adj_list.lower, 7287 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7288 ldev; 7289 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7290 if (ignore) 7291 continue; 7292 if (max_depth < ldev->lower_level) 7293 max_depth = ldev->lower_level; 7294 } 7295 7296 return max_depth; 7297 } 7298 7299 static int __netdev_update_upper_level(struct net_device *dev, 7300 struct netdev_nested_priv *__unused) 7301 { 7302 dev->upper_level = __netdev_upper_depth(dev) + 1; 7303 return 0; 7304 } 7305 7306 #ifdef CONFIG_LOCKDEP 7307 static LIST_HEAD(net_unlink_list); 7308 7309 static void net_unlink_todo(struct net_device *dev) 7310 { 7311 if (list_empty(&dev->unlink_list)) 7312 list_add_tail(&dev->unlink_list, &net_unlink_list); 7313 } 7314 #endif 7315 7316 static int __netdev_update_lower_level(struct net_device *dev, 7317 struct netdev_nested_priv *priv) 7318 { 7319 dev->lower_level = __netdev_lower_depth(dev) + 1; 7320 7321 #ifdef CONFIG_LOCKDEP 7322 if (!priv) 7323 return 0; 7324 7325 if (priv->flags & NESTED_SYNC_IMM) 7326 dev->nested_level = dev->lower_level - 1; 7327 if (priv->flags & NESTED_SYNC_TODO) 7328 net_unlink_todo(dev); 7329 #endif 7330 return 0; 7331 } 7332 7333 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7334 int (*fn)(struct net_device *dev, 7335 struct netdev_nested_priv *priv), 7336 struct netdev_nested_priv *priv) 7337 { 7338 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7339 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7340 int ret, cur = 0; 7341 7342 now = dev; 7343 iter = &dev->adj_list.lower; 7344 7345 while (1) { 7346 if (now != dev) { 7347 ret = fn(now, priv); 7348 if (ret) 7349 return ret; 7350 } 7351 7352 next = NULL; 7353 while (1) { 7354 ldev = netdev_next_lower_dev_rcu(now, &iter); 7355 if (!ldev) 7356 break; 7357 7358 next = ldev; 7359 niter = &ldev->adj_list.lower; 7360 dev_stack[cur] = now; 7361 iter_stack[cur++] = iter; 7362 break; 7363 } 7364 7365 if (!next) { 7366 if (!cur) 7367 return 0; 7368 next = dev_stack[--cur]; 7369 niter = iter_stack[cur]; 7370 } 7371 7372 now = next; 7373 iter = niter; 7374 } 7375 7376 return 0; 7377 } 7378 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7379 7380 /** 7381 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7382 * lower neighbour list, RCU 7383 * variant 7384 * @dev: device 7385 * 7386 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7387 * list. The caller must hold RCU read lock. 7388 */ 7389 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7390 { 7391 struct netdev_adjacent *lower; 7392 7393 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7394 struct netdev_adjacent, list); 7395 if (lower) 7396 return lower->private; 7397 return NULL; 7398 } 7399 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7400 7401 /** 7402 * netdev_master_upper_dev_get_rcu - Get master upper device 7403 * @dev: device 7404 * 7405 * Find a master upper device and return pointer to it or NULL in case 7406 * it's not there. The caller must hold the RCU read lock. 7407 */ 7408 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7409 { 7410 struct netdev_adjacent *upper; 7411 7412 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7413 struct netdev_adjacent, list); 7414 if (upper && likely(upper->master)) 7415 return upper->dev; 7416 return NULL; 7417 } 7418 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7419 7420 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7421 struct net_device *adj_dev, 7422 struct list_head *dev_list) 7423 { 7424 char linkname[IFNAMSIZ+7]; 7425 7426 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7427 "upper_%s" : "lower_%s", adj_dev->name); 7428 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7429 linkname); 7430 } 7431 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7432 char *name, 7433 struct list_head *dev_list) 7434 { 7435 char linkname[IFNAMSIZ+7]; 7436 7437 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7438 "upper_%s" : "lower_%s", name); 7439 sysfs_remove_link(&(dev->dev.kobj), linkname); 7440 } 7441 7442 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7443 struct net_device *adj_dev, 7444 struct list_head *dev_list) 7445 { 7446 return (dev_list == &dev->adj_list.upper || 7447 dev_list == &dev->adj_list.lower) && 7448 net_eq(dev_net(dev), dev_net(adj_dev)); 7449 } 7450 7451 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7452 struct net_device *adj_dev, 7453 struct list_head *dev_list, 7454 void *private, bool master) 7455 { 7456 struct netdev_adjacent *adj; 7457 int ret; 7458 7459 adj = __netdev_find_adj(adj_dev, dev_list); 7460 7461 if (adj) { 7462 adj->ref_nr += 1; 7463 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7464 dev->name, adj_dev->name, adj->ref_nr); 7465 7466 return 0; 7467 } 7468 7469 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7470 if (!adj) 7471 return -ENOMEM; 7472 7473 adj->dev = adj_dev; 7474 adj->master = master; 7475 adj->ref_nr = 1; 7476 adj->private = private; 7477 adj->ignore = false; 7478 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 7479 7480 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7481 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7482 7483 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7484 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7485 if (ret) 7486 goto free_adj; 7487 } 7488 7489 /* Ensure that master link is always the first item in list. */ 7490 if (master) { 7491 ret = sysfs_create_link(&(dev->dev.kobj), 7492 &(adj_dev->dev.kobj), "master"); 7493 if (ret) 7494 goto remove_symlinks; 7495 7496 list_add_rcu(&adj->list, dev_list); 7497 } else { 7498 list_add_tail_rcu(&adj->list, dev_list); 7499 } 7500 7501 return 0; 7502 7503 remove_symlinks: 7504 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7505 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7506 free_adj: 7507 netdev_put(adj_dev, &adj->dev_tracker); 7508 kfree(adj); 7509 7510 return ret; 7511 } 7512 7513 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7514 struct net_device *adj_dev, 7515 u16 ref_nr, 7516 struct list_head *dev_list) 7517 { 7518 struct netdev_adjacent *adj; 7519 7520 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7521 dev->name, adj_dev->name, ref_nr); 7522 7523 adj = __netdev_find_adj(adj_dev, dev_list); 7524 7525 if (!adj) { 7526 pr_err("Adjacency does not exist for device %s from %s\n", 7527 dev->name, adj_dev->name); 7528 WARN_ON(1); 7529 return; 7530 } 7531 7532 if (adj->ref_nr > ref_nr) { 7533 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7534 dev->name, adj_dev->name, ref_nr, 7535 adj->ref_nr - ref_nr); 7536 adj->ref_nr -= ref_nr; 7537 return; 7538 } 7539 7540 if (adj->master) 7541 sysfs_remove_link(&(dev->dev.kobj), "master"); 7542 7543 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7544 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7545 7546 list_del_rcu(&adj->list); 7547 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7548 adj_dev->name, dev->name, adj_dev->name); 7549 netdev_put(adj_dev, &adj->dev_tracker); 7550 kfree_rcu(adj, rcu); 7551 } 7552 7553 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7554 struct net_device *upper_dev, 7555 struct list_head *up_list, 7556 struct list_head *down_list, 7557 void *private, bool master) 7558 { 7559 int ret; 7560 7561 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7562 private, master); 7563 if (ret) 7564 return ret; 7565 7566 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7567 private, false); 7568 if (ret) { 7569 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7570 return ret; 7571 } 7572 7573 return 0; 7574 } 7575 7576 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7577 struct net_device *upper_dev, 7578 u16 ref_nr, 7579 struct list_head *up_list, 7580 struct list_head *down_list) 7581 { 7582 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7583 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7584 } 7585 7586 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7587 struct net_device *upper_dev, 7588 void *private, bool master) 7589 { 7590 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7591 &dev->adj_list.upper, 7592 &upper_dev->adj_list.lower, 7593 private, master); 7594 } 7595 7596 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7597 struct net_device *upper_dev) 7598 { 7599 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7600 &dev->adj_list.upper, 7601 &upper_dev->adj_list.lower); 7602 } 7603 7604 static int __netdev_upper_dev_link(struct net_device *dev, 7605 struct net_device *upper_dev, bool master, 7606 void *upper_priv, void *upper_info, 7607 struct netdev_nested_priv *priv, 7608 struct netlink_ext_ack *extack) 7609 { 7610 struct netdev_notifier_changeupper_info changeupper_info = { 7611 .info = { 7612 .dev = dev, 7613 .extack = extack, 7614 }, 7615 .upper_dev = upper_dev, 7616 .master = master, 7617 .linking = true, 7618 .upper_info = upper_info, 7619 }; 7620 struct net_device *master_dev; 7621 int ret = 0; 7622 7623 ASSERT_RTNL(); 7624 7625 if (dev == upper_dev) 7626 return -EBUSY; 7627 7628 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7629 if (__netdev_has_upper_dev(upper_dev, dev)) 7630 return -EBUSY; 7631 7632 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7633 return -EMLINK; 7634 7635 if (!master) { 7636 if (__netdev_has_upper_dev(dev, upper_dev)) 7637 return -EEXIST; 7638 } else { 7639 master_dev = __netdev_master_upper_dev_get(dev); 7640 if (master_dev) 7641 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7642 } 7643 7644 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7645 &changeupper_info.info); 7646 ret = notifier_to_errno(ret); 7647 if (ret) 7648 return ret; 7649 7650 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7651 master); 7652 if (ret) 7653 return ret; 7654 7655 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7656 &changeupper_info.info); 7657 ret = notifier_to_errno(ret); 7658 if (ret) 7659 goto rollback; 7660 7661 __netdev_update_upper_level(dev, NULL); 7662 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7663 7664 __netdev_update_lower_level(upper_dev, priv); 7665 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7666 priv); 7667 7668 return 0; 7669 7670 rollback: 7671 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7672 7673 return ret; 7674 } 7675 7676 /** 7677 * netdev_upper_dev_link - Add a link to the upper device 7678 * @dev: device 7679 * @upper_dev: new upper device 7680 * @extack: netlink extended ack 7681 * 7682 * Adds a link to device which is upper to this one. The caller must hold 7683 * the RTNL lock. On a failure a negative errno code is returned. 7684 * On success the reference counts are adjusted and the function 7685 * returns zero. 7686 */ 7687 int netdev_upper_dev_link(struct net_device *dev, 7688 struct net_device *upper_dev, 7689 struct netlink_ext_ack *extack) 7690 { 7691 struct netdev_nested_priv priv = { 7692 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7693 .data = NULL, 7694 }; 7695 7696 return __netdev_upper_dev_link(dev, upper_dev, false, 7697 NULL, NULL, &priv, extack); 7698 } 7699 EXPORT_SYMBOL(netdev_upper_dev_link); 7700 7701 /** 7702 * netdev_master_upper_dev_link - Add a master link to the upper device 7703 * @dev: device 7704 * @upper_dev: new upper device 7705 * @upper_priv: upper device private 7706 * @upper_info: upper info to be passed down via notifier 7707 * @extack: netlink extended ack 7708 * 7709 * Adds a link to device which is upper to this one. In this case, only 7710 * one master upper device can be linked, although other non-master devices 7711 * might be linked as well. The caller must hold the RTNL lock. 7712 * On a failure a negative errno code is returned. On success the reference 7713 * counts are adjusted and the function returns zero. 7714 */ 7715 int netdev_master_upper_dev_link(struct net_device *dev, 7716 struct net_device *upper_dev, 7717 void *upper_priv, void *upper_info, 7718 struct netlink_ext_ack *extack) 7719 { 7720 struct netdev_nested_priv priv = { 7721 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7722 .data = NULL, 7723 }; 7724 7725 return __netdev_upper_dev_link(dev, upper_dev, true, 7726 upper_priv, upper_info, &priv, extack); 7727 } 7728 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7729 7730 static void __netdev_upper_dev_unlink(struct net_device *dev, 7731 struct net_device *upper_dev, 7732 struct netdev_nested_priv *priv) 7733 { 7734 struct netdev_notifier_changeupper_info changeupper_info = { 7735 .info = { 7736 .dev = dev, 7737 }, 7738 .upper_dev = upper_dev, 7739 .linking = false, 7740 }; 7741 7742 ASSERT_RTNL(); 7743 7744 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7745 7746 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7747 &changeupper_info.info); 7748 7749 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7750 7751 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7752 &changeupper_info.info); 7753 7754 __netdev_update_upper_level(dev, NULL); 7755 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7756 7757 __netdev_update_lower_level(upper_dev, priv); 7758 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7759 priv); 7760 } 7761 7762 /** 7763 * netdev_upper_dev_unlink - Removes a link to upper device 7764 * @dev: device 7765 * @upper_dev: new upper device 7766 * 7767 * Removes a link to device which is upper to this one. The caller must hold 7768 * the RTNL lock. 7769 */ 7770 void netdev_upper_dev_unlink(struct net_device *dev, 7771 struct net_device *upper_dev) 7772 { 7773 struct netdev_nested_priv priv = { 7774 .flags = NESTED_SYNC_TODO, 7775 .data = NULL, 7776 }; 7777 7778 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 7779 } 7780 EXPORT_SYMBOL(netdev_upper_dev_unlink); 7781 7782 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 7783 struct net_device *lower_dev, 7784 bool val) 7785 { 7786 struct netdev_adjacent *adj; 7787 7788 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 7789 if (adj) 7790 adj->ignore = val; 7791 7792 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 7793 if (adj) 7794 adj->ignore = val; 7795 } 7796 7797 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 7798 struct net_device *lower_dev) 7799 { 7800 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 7801 } 7802 7803 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 7804 struct net_device *lower_dev) 7805 { 7806 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 7807 } 7808 7809 int netdev_adjacent_change_prepare(struct net_device *old_dev, 7810 struct net_device *new_dev, 7811 struct net_device *dev, 7812 struct netlink_ext_ack *extack) 7813 { 7814 struct netdev_nested_priv priv = { 7815 .flags = 0, 7816 .data = NULL, 7817 }; 7818 int err; 7819 7820 if (!new_dev) 7821 return 0; 7822 7823 if (old_dev && new_dev != old_dev) 7824 netdev_adjacent_dev_disable(dev, old_dev); 7825 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 7826 extack); 7827 if (err) { 7828 if (old_dev && new_dev != old_dev) 7829 netdev_adjacent_dev_enable(dev, old_dev); 7830 return err; 7831 } 7832 7833 return 0; 7834 } 7835 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 7836 7837 void netdev_adjacent_change_commit(struct net_device *old_dev, 7838 struct net_device *new_dev, 7839 struct net_device *dev) 7840 { 7841 struct netdev_nested_priv priv = { 7842 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7843 .data = NULL, 7844 }; 7845 7846 if (!new_dev || !old_dev) 7847 return; 7848 7849 if (new_dev == old_dev) 7850 return; 7851 7852 netdev_adjacent_dev_enable(dev, old_dev); 7853 __netdev_upper_dev_unlink(old_dev, dev, &priv); 7854 } 7855 EXPORT_SYMBOL(netdev_adjacent_change_commit); 7856 7857 void netdev_adjacent_change_abort(struct net_device *old_dev, 7858 struct net_device *new_dev, 7859 struct net_device *dev) 7860 { 7861 struct netdev_nested_priv priv = { 7862 .flags = 0, 7863 .data = NULL, 7864 }; 7865 7866 if (!new_dev) 7867 return; 7868 7869 if (old_dev && new_dev != old_dev) 7870 netdev_adjacent_dev_enable(dev, old_dev); 7871 7872 __netdev_upper_dev_unlink(new_dev, dev, &priv); 7873 } 7874 EXPORT_SYMBOL(netdev_adjacent_change_abort); 7875 7876 /** 7877 * netdev_bonding_info_change - Dispatch event about slave change 7878 * @dev: device 7879 * @bonding_info: info to dispatch 7880 * 7881 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 7882 * The caller must hold the RTNL lock. 7883 */ 7884 void netdev_bonding_info_change(struct net_device *dev, 7885 struct netdev_bonding_info *bonding_info) 7886 { 7887 struct netdev_notifier_bonding_info info = { 7888 .info.dev = dev, 7889 }; 7890 7891 memcpy(&info.bonding_info, bonding_info, 7892 sizeof(struct netdev_bonding_info)); 7893 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 7894 &info.info); 7895 } 7896 EXPORT_SYMBOL(netdev_bonding_info_change); 7897 7898 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 7899 struct netlink_ext_ack *extack) 7900 { 7901 struct netdev_notifier_offload_xstats_info info = { 7902 .info.dev = dev, 7903 .info.extack = extack, 7904 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7905 }; 7906 int err; 7907 int rc; 7908 7909 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 7910 GFP_KERNEL); 7911 if (!dev->offload_xstats_l3) 7912 return -ENOMEM; 7913 7914 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 7915 NETDEV_OFFLOAD_XSTATS_DISABLE, 7916 &info.info); 7917 err = notifier_to_errno(rc); 7918 if (err) 7919 goto free_stats; 7920 7921 return 0; 7922 7923 free_stats: 7924 kfree(dev->offload_xstats_l3); 7925 dev->offload_xstats_l3 = NULL; 7926 return err; 7927 } 7928 7929 int netdev_offload_xstats_enable(struct net_device *dev, 7930 enum netdev_offload_xstats_type type, 7931 struct netlink_ext_ack *extack) 7932 { 7933 ASSERT_RTNL(); 7934 7935 if (netdev_offload_xstats_enabled(dev, type)) 7936 return -EALREADY; 7937 7938 switch (type) { 7939 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7940 return netdev_offload_xstats_enable_l3(dev, extack); 7941 } 7942 7943 WARN_ON(1); 7944 return -EINVAL; 7945 } 7946 EXPORT_SYMBOL(netdev_offload_xstats_enable); 7947 7948 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 7949 { 7950 struct netdev_notifier_offload_xstats_info info = { 7951 .info.dev = dev, 7952 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7953 }; 7954 7955 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 7956 &info.info); 7957 kfree(dev->offload_xstats_l3); 7958 dev->offload_xstats_l3 = NULL; 7959 } 7960 7961 int netdev_offload_xstats_disable(struct net_device *dev, 7962 enum netdev_offload_xstats_type type) 7963 { 7964 ASSERT_RTNL(); 7965 7966 if (!netdev_offload_xstats_enabled(dev, type)) 7967 return -EALREADY; 7968 7969 switch (type) { 7970 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7971 netdev_offload_xstats_disable_l3(dev); 7972 return 0; 7973 } 7974 7975 WARN_ON(1); 7976 return -EINVAL; 7977 } 7978 EXPORT_SYMBOL(netdev_offload_xstats_disable); 7979 7980 static void netdev_offload_xstats_disable_all(struct net_device *dev) 7981 { 7982 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 7983 } 7984 7985 static struct rtnl_hw_stats64 * 7986 netdev_offload_xstats_get_ptr(const struct net_device *dev, 7987 enum netdev_offload_xstats_type type) 7988 { 7989 switch (type) { 7990 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7991 return dev->offload_xstats_l3; 7992 } 7993 7994 WARN_ON(1); 7995 return NULL; 7996 } 7997 7998 bool netdev_offload_xstats_enabled(const struct net_device *dev, 7999 enum netdev_offload_xstats_type type) 8000 { 8001 ASSERT_RTNL(); 8002 8003 return netdev_offload_xstats_get_ptr(dev, type); 8004 } 8005 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 8006 8007 struct netdev_notifier_offload_xstats_ru { 8008 bool used; 8009 }; 8010 8011 struct netdev_notifier_offload_xstats_rd { 8012 struct rtnl_hw_stats64 stats; 8013 bool used; 8014 }; 8015 8016 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 8017 const struct rtnl_hw_stats64 *src) 8018 { 8019 dest->rx_packets += src->rx_packets; 8020 dest->tx_packets += src->tx_packets; 8021 dest->rx_bytes += src->rx_bytes; 8022 dest->tx_bytes += src->tx_bytes; 8023 dest->rx_errors += src->rx_errors; 8024 dest->tx_errors += src->tx_errors; 8025 dest->rx_dropped += src->rx_dropped; 8026 dest->tx_dropped += src->tx_dropped; 8027 dest->multicast += src->multicast; 8028 } 8029 8030 static int netdev_offload_xstats_get_used(struct net_device *dev, 8031 enum netdev_offload_xstats_type type, 8032 bool *p_used, 8033 struct netlink_ext_ack *extack) 8034 { 8035 struct netdev_notifier_offload_xstats_ru report_used = {}; 8036 struct netdev_notifier_offload_xstats_info info = { 8037 .info.dev = dev, 8038 .info.extack = extack, 8039 .type = type, 8040 .report_used = &report_used, 8041 }; 8042 int rc; 8043 8044 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8045 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8046 &info.info); 8047 *p_used = report_used.used; 8048 return notifier_to_errno(rc); 8049 } 8050 8051 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8052 enum netdev_offload_xstats_type type, 8053 struct rtnl_hw_stats64 *p_stats, 8054 bool *p_used, 8055 struct netlink_ext_ack *extack) 8056 { 8057 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8058 struct netdev_notifier_offload_xstats_info info = { 8059 .info.dev = dev, 8060 .info.extack = extack, 8061 .type = type, 8062 .report_delta = &report_delta, 8063 }; 8064 struct rtnl_hw_stats64 *stats; 8065 int rc; 8066 8067 stats = netdev_offload_xstats_get_ptr(dev, type); 8068 if (WARN_ON(!stats)) 8069 return -EINVAL; 8070 8071 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8072 &info.info); 8073 8074 /* Cache whatever we got, even if there was an error, otherwise the 8075 * successful stats retrievals would get lost. 8076 */ 8077 netdev_hw_stats64_add(stats, &report_delta.stats); 8078 8079 if (p_stats) 8080 *p_stats = *stats; 8081 *p_used = report_delta.used; 8082 8083 return notifier_to_errno(rc); 8084 } 8085 8086 int netdev_offload_xstats_get(struct net_device *dev, 8087 enum netdev_offload_xstats_type type, 8088 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8089 struct netlink_ext_ack *extack) 8090 { 8091 ASSERT_RTNL(); 8092 8093 if (p_stats) 8094 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8095 p_used, extack); 8096 else 8097 return netdev_offload_xstats_get_used(dev, type, p_used, 8098 extack); 8099 } 8100 EXPORT_SYMBOL(netdev_offload_xstats_get); 8101 8102 void 8103 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8104 const struct rtnl_hw_stats64 *stats) 8105 { 8106 report_delta->used = true; 8107 netdev_hw_stats64_add(&report_delta->stats, stats); 8108 } 8109 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8110 8111 void 8112 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8113 { 8114 report_used->used = true; 8115 } 8116 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8117 8118 void netdev_offload_xstats_push_delta(struct net_device *dev, 8119 enum netdev_offload_xstats_type type, 8120 const struct rtnl_hw_stats64 *p_stats) 8121 { 8122 struct rtnl_hw_stats64 *stats; 8123 8124 ASSERT_RTNL(); 8125 8126 stats = netdev_offload_xstats_get_ptr(dev, type); 8127 if (WARN_ON(!stats)) 8128 return; 8129 8130 netdev_hw_stats64_add(stats, p_stats); 8131 } 8132 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8133 8134 /** 8135 * netdev_get_xmit_slave - Get the xmit slave of master device 8136 * @dev: device 8137 * @skb: The packet 8138 * @all_slaves: assume all the slaves are active 8139 * 8140 * The reference counters are not incremented so the caller must be 8141 * careful with locks. The caller must hold RCU lock. 8142 * %NULL is returned if no slave is found. 8143 */ 8144 8145 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8146 struct sk_buff *skb, 8147 bool all_slaves) 8148 { 8149 const struct net_device_ops *ops = dev->netdev_ops; 8150 8151 if (!ops->ndo_get_xmit_slave) 8152 return NULL; 8153 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8154 } 8155 EXPORT_SYMBOL(netdev_get_xmit_slave); 8156 8157 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8158 struct sock *sk) 8159 { 8160 const struct net_device_ops *ops = dev->netdev_ops; 8161 8162 if (!ops->ndo_sk_get_lower_dev) 8163 return NULL; 8164 return ops->ndo_sk_get_lower_dev(dev, sk); 8165 } 8166 8167 /** 8168 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8169 * @dev: device 8170 * @sk: the socket 8171 * 8172 * %NULL is returned if no lower device is found. 8173 */ 8174 8175 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8176 struct sock *sk) 8177 { 8178 struct net_device *lower; 8179 8180 lower = netdev_sk_get_lower_dev(dev, sk); 8181 while (lower) { 8182 dev = lower; 8183 lower = netdev_sk_get_lower_dev(dev, sk); 8184 } 8185 8186 return dev; 8187 } 8188 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8189 8190 static void netdev_adjacent_add_links(struct net_device *dev) 8191 { 8192 struct netdev_adjacent *iter; 8193 8194 struct net *net = dev_net(dev); 8195 8196 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8197 if (!net_eq(net, dev_net(iter->dev))) 8198 continue; 8199 netdev_adjacent_sysfs_add(iter->dev, dev, 8200 &iter->dev->adj_list.lower); 8201 netdev_adjacent_sysfs_add(dev, iter->dev, 8202 &dev->adj_list.upper); 8203 } 8204 8205 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8206 if (!net_eq(net, dev_net(iter->dev))) 8207 continue; 8208 netdev_adjacent_sysfs_add(iter->dev, dev, 8209 &iter->dev->adj_list.upper); 8210 netdev_adjacent_sysfs_add(dev, iter->dev, 8211 &dev->adj_list.lower); 8212 } 8213 } 8214 8215 static void netdev_adjacent_del_links(struct net_device *dev) 8216 { 8217 struct netdev_adjacent *iter; 8218 8219 struct net *net = dev_net(dev); 8220 8221 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8222 if (!net_eq(net, dev_net(iter->dev))) 8223 continue; 8224 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8225 &iter->dev->adj_list.lower); 8226 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8227 &dev->adj_list.upper); 8228 } 8229 8230 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8231 if (!net_eq(net, dev_net(iter->dev))) 8232 continue; 8233 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8234 &iter->dev->adj_list.upper); 8235 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8236 &dev->adj_list.lower); 8237 } 8238 } 8239 8240 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8241 { 8242 struct netdev_adjacent *iter; 8243 8244 struct net *net = dev_net(dev); 8245 8246 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8247 if (!net_eq(net, dev_net(iter->dev))) 8248 continue; 8249 netdev_adjacent_sysfs_del(iter->dev, oldname, 8250 &iter->dev->adj_list.lower); 8251 netdev_adjacent_sysfs_add(iter->dev, dev, 8252 &iter->dev->adj_list.lower); 8253 } 8254 8255 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8256 if (!net_eq(net, dev_net(iter->dev))) 8257 continue; 8258 netdev_adjacent_sysfs_del(iter->dev, oldname, 8259 &iter->dev->adj_list.upper); 8260 netdev_adjacent_sysfs_add(iter->dev, dev, 8261 &iter->dev->adj_list.upper); 8262 } 8263 } 8264 8265 void *netdev_lower_dev_get_private(struct net_device *dev, 8266 struct net_device *lower_dev) 8267 { 8268 struct netdev_adjacent *lower; 8269 8270 if (!lower_dev) 8271 return NULL; 8272 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8273 if (!lower) 8274 return NULL; 8275 8276 return lower->private; 8277 } 8278 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8279 8280 8281 /** 8282 * netdev_lower_state_changed - Dispatch event about lower device state change 8283 * @lower_dev: device 8284 * @lower_state_info: state to dispatch 8285 * 8286 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8287 * The caller must hold the RTNL lock. 8288 */ 8289 void netdev_lower_state_changed(struct net_device *lower_dev, 8290 void *lower_state_info) 8291 { 8292 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 8293 .info.dev = lower_dev, 8294 }; 8295 8296 ASSERT_RTNL(); 8297 changelowerstate_info.lower_state_info = lower_state_info; 8298 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 8299 &changelowerstate_info.info); 8300 } 8301 EXPORT_SYMBOL(netdev_lower_state_changed); 8302 8303 static void dev_change_rx_flags(struct net_device *dev, int flags) 8304 { 8305 const struct net_device_ops *ops = dev->netdev_ops; 8306 8307 if (ops->ndo_change_rx_flags) 8308 ops->ndo_change_rx_flags(dev, flags); 8309 } 8310 8311 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 8312 { 8313 unsigned int old_flags = dev->flags; 8314 kuid_t uid; 8315 kgid_t gid; 8316 8317 ASSERT_RTNL(); 8318 8319 dev->flags |= IFF_PROMISC; 8320 dev->promiscuity += inc; 8321 if (dev->promiscuity == 0) { 8322 /* 8323 * Avoid overflow. 8324 * If inc causes overflow, untouch promisc and return error. 8325 */ 8326 if (inc < 0) 8327 dev->flags &= ~IFF_PROMISC; 8328 else { 8329 dev->promiscuity -= inc; 8330 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 8331 return -EOVERFLOW; 8332 } 8333 } 8334 if (dev->flags != old_flags) { 8335 pr_info("device %s %s promiscuous mode\n", 8336 dev->name, 8337 dev->flags & IFF_PROMISC ? "entered" : "left"); 8338 if (audit_enabled) { 8339 current_uid_gid(&uid, &gid); 8340 audit_log(audit_context(), GFP_ATOMIC, 8341 AUDIT_ANOM_PROMISCUOUS, 8342 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 8343 dev->name, (dev->flags & IFF_PROMISC), 8344 (old_flags & IFF_PROMISC), 8345 from_kuid(&init_user_ns, audit_get_loginuid(current)), 8346 from_kuid(&init_user_ns, uid), 8347 from_kgid(&init_user_ns, gid), 8348 audit_get_sessionid(current)); 8349 } 8350 8351 dev_change_rx_flags(dev, IFF_PROMISC); 8352 } 8353 if (notify) 8354 __dev_notify_flags(dev, old_flags, IFF_PROMISC); 8355 return 0; 8356 } 8357 8358 /** 8359 * dev_set_promiscuity - update promiscuity count on a device 8360 * @dev: device 8361 * @inc: modifier 8362 * 8363 * Add or remove promiscuity from a device. While the count in the device 8364 * remains above zero the interface remains promiscuous. Once it hits zero 8365 * the device reverts back to normal filtering operation. A negative inc 8366 * value is used to drop promiscuity on the device. 8367 * Return 0 if successful or a negative errno code on error. 8368 */ 8369 int dev_set_promiscuity(struct net_device *dev, int inc) 8370 { 8371 unsigned int old_flags = dev->flags; 8372 int err; 8373 8374 err = __dev_set_promiscuity(dev, inc, true); 8375 if (err < 0) 8376 return err; 8377 if (dev->flags != old_flags) 8378 dev_set_rx_mode(dev); 8379 return err; 8380 } 8381 EXPORT_SYMBOL(dev_set_promiscuity); 8382 8383 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 8384 { 8385 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 8386 8387 ASSERT_RTNL(); 8388 8389 dev->flags |= IFF_ALLMULTI; 8390 dev->allmulti += inc; 8391 if (dev->allmulti == 0) { 8392 /* 8393 * Avoid overflow. 8394 * If inc causes overflow, untouch allmulti and return error. 8395 */ 8396 if (inc < 0) 8397 dev->flags &= ~IFF_ALLMULTI; 8398 else { 8399 dev->allmulti -= inc; 8400 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 8401 return -EOVERFLOW; 8402 } 8403 } 8404 if (dev->flags ^ old_flags) { 8405 dev_change_rx_flags(dev, IFF_ALLMULTI); 8406 dev_set_rx_mode(dev); 8407 if (notify) 8408 __dev_notify_flags(dev, old_flags, 8409 dev->gflags ^ old_gflags); 8410 } 8411 return 0; 8412 } 8413 8414 /** 8415 * dev_set_allmulti - update allmulti count on a device 8416 * @dev: device 8417 * @inc: modifier 8418 * 8419 * Add or remove reception of all multicast frames to a device. While the 8420 * count in the device remains above zero the interface remains listening 8421 * to all interfaces. Once it hits zero the device reverts back to normal 8422 * filtering operation. A negative @inc value is used to drop the counter 8423 * when releasing a resource needing all multicasts. 8424 * Return 0 if successful or a negative errno code on error. 8425 */ 8426 8427 int dev_set_allmulti(struct net_device *dev, int inc) 8428 { 8429 return __dev_set_allmulti(dev, inc, true); 8430 } 8431 EXPORT_SYMBOL(dev_set_allmulti); 8432 8433 /* 8434 * Upload unicast and multicast address lists to device and 8435 * configure RX filtering. When the device doesn't support unicast 8436 * filtering it is put in promiscuous mode while unicast addresses 8437 * are present. 8438 */ 8439 void __dev_set_rx_mode(struct net_device *dev) 8440 { 8441 const struct net_device_ops *ops = dev->netdev_ops; 8442 8443 /* dev_open will call this function so the list will stay sane. */ 8444 if (!(dev->flags&IFF_UP)) 8445 return; 8446 8447 if (!netif_device_present(dev)) 8448 return; 8449 8450 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8451 /* Unicast addresses changes may only happen under the rtnl, 8452 * therefore calling __dev_set_promiscuity here is safe. 8453 */ 8454 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8455 __dev_set_promiscuity(dev, 1, false); 8456 dev->uc_promisc = true; 8457 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8458 __dev_set_promiscuity(dev, -1, false); 8459 dev->uc_promisc = false; 8460 } 8461 } 8462 8463 if (ops->ndo_set_rx_mode) 8464 ops->ndo_set_rx_mode(dev); 8465 } 8466 8467 void dev_set_rx_mode(struct net_device *dev) 8468 { 8469 netif_addr_lock_bh(dev); 8470 __dev_set_rx_mode(dev); 8471 netif_addr_unlock_bh(dev); 8472 } 8473 8474 /** 8475 * dev_get_flags - get flags reported to userspace 8476 * @dev: device 8477 * 8478 * Get the combination of flag bits exported through APIs to userspace. 8479 */ 8480 unsigned int dev_get_flags(const struct net_device *dev) 8481 { 8482 unsigned int flags; 8483 8484 flags = (dev->flags & ~(IFF_PROMISC | 8485 IFF_ALLMULTI | 8486 IFF_RUNNING | 8487 IFF_LOWER_UP | 8488 IFF_DORMANT)) | 8489 (dev->gflags & (IFF_PROMISC | 8490 IFF_ALLMULTI)); 8491 8492 if (netif_running(dev)) { 8493 if (netif_oper_up(dev)) 8494 flags |= IFF_RUNNING; 8495 if (netif_carrier_ok(dev)) 8496 flags |= IFF_LOWER_UP; 8497 if (netif_dormant(dev)) 8498 flags |= IFF_DORMANT; 8499 } 8500 8501 return flags; 8502 } 8503 EXPORT_SYMBOL(dev_get_flags); 8504 8505 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8506 struct netlink_ext_ack *extack) 8507 { 8508 unsigned int old_flags = dev->flags; 8509 int ret; 8510 8511 ASSERT_RTNL(); 8512 8513 /* 8514 * Set the flags on our device. 8515 */ 8516 8517 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8518 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8519 IFF_AUTOMEDIA)) | 8520 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8521 IFF_ALLMULTI)); 8522 8523 /* 8524 * Load in the correct multicast list now the flags have changed. 8525 */ 8526 8527 if ((old_flags ^ flags) & IFF_MULTICAST) 8528 dev_change_rx_flags(dev, IFF_MULTICAST); 8529 8530 dev_set_rx_mode(dev); 8531 8532 /* 8533 * Have we downed the interface. We handle IFF_UP ourselves 8534 * according to user attempts to set it, rather than blindly 8535 * setting it. 8536 */ 8537 8538 ret = 0; 8539 if ((old_flags ^ flags) & IFF_UP) { 8540 if (old_flags & IFF_UP) 8541 __dev_close(dev); 8542 else 8543 ret = __dev_open(dev, extack); 8544 } 8545 8546 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8547 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8548 unsigned int old_flags = dev->flags; 8549 8550 dev->gflags ^= IFF_PROMISC; 8551 8552 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8553 if (dev->flags != old_flags) 8554 dev_set_rx_mode(dev); 8555 } 8556 8557 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8558 * is important. Some (broken) drivers set IFF_PROMISC, when 8559 * IFF_ALLMULTI is requested not asking us and not reporting. 8560 */ 8561 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8562 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8563 8564 dev->gflags ^= IFF_ALLMULTI; 8565 __dev_set_allmulti(dev, inc, false); 8566 } 8567 8568 return ret; 8569 } 8570 8571 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8572 unsigned int gchanges) 8573 { 8574 unsigned int changes = dev->flags ^ old_flags; 8575 8576 if (gchanges) 8577 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC); 8578 8579 if (changes & IFF_UP) { 8580 if (dev->flags & IFF_UP) 8581 call_netdevice_notifiers(NETDEV_UP, dev); 8582 else 8583 call_netdevice_notifiers(NETDEV_DOWN, dev); 8584 } 8585 8586 if (dev->flags & IFF_UP && 8587 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8588 struct netdev_notifier_change_info change_info = { 8589 .info = { 8590 .dev = dev, 8591 }, 8592 .flags_changed = changes, 8593 }; 8594 8595 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8596 } 8597 } 8598 8599 /** 8600 * dev_change_flags - change device settings 8601 * @dev: device 8602 * @flags: device state flags 8603 * @extack: netlink extended ack 8604 * 8605 * Change settings on device based state flags. The flags are 8606 * in the userspace exported format. 8607 */ 8608 int dev_change_flags(struct net_device *dev, unsigned int flags, 8609 struct netlink_ext_ack *extack) 8610 { 8611 int ret; 8612 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8613 8614 ret = __dev_change_flags(dev, flags, extack); 8615 if (ret < 0) 8616 return ret; 8617 8618 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8619 __dev_notify_flags(dev, old_flags, changes); 8620 return ret; 8621 } 8622 EXPORT_SYMBOL(dev_change_flags); 8623 8624 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8625 { 8626 const struct net_device_ops *ops = dev->netdev_ops; 8627 8628 if (ops->ndo_change_mtu) 8629 return ops->ndo_change_mtu(dev, new_mtu); 8630 8631 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8632 WRITE_ONCE(dev->mtu, new_mtu); 8633 return 0; 8634 } 8635 EXPORT_SYMBOL(__dev_set_mtu); 8636 8637 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8638 struct netlink_ext_ack *extack) 8639 { 8640 /* MTU must be positive, and in range */ 8641 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8642 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8643 return -EINVAL; 8644 } 8645 8646 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8647 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8648 return -EINVAL; 8649 } 8650 return 0; 8651 } 8652 8653 /** 8654 * dev_set_mtu_ext - Change maximum transfer unit 8655 * @dev: device 8656 * @new_mtu: new transfer unit 8657 * @extack: netlink extended ack 8658 * 8659 * Change the maximum transfer size of the network device. 8660 */ 8661 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8662 struct netlink_ext_ack *extack) 8663 { 8664 int err, orig_mtu; 8665 8666 if (new_mtu == dev->mtu) 8667 return 0; 8668 8669 err = dev_validate_mtu(dev, new_mtu, extack); 8670 if (err) 8671 return err; 8672 8673 if (!netif_device_present(dev)) 8674 return -ENODEV; 8675 8676 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8677 err = notifier_to_errno(err); 8678 if (err) 8679 return err; 8680 8681 orig_mtu = dev->mtu; 8682 err = __dev_set_mtu(dev, new_mtu); 8683 8684 if (!err) { 8685 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8686 orig_mtu); 8687 err = notifier_to_errno(err); 8688 if (err) { 8689 /* setting mtu back and notifying everyone again, 8690 * so that they have a chance to revert changes. 8691 */ 8692 __dev_set_mtu(dev, orig_mtu); 8693 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8694 new_mtu); 8695 } 8696 } 8697 return err; 8698 } 8699 8700 int dev_set_mtu(struct net_device *dev, int new_mtu) 8701 { 8702 struct netlink_ext_ack extack; 8703 int err; 8704 8705 memset(&extack, 0, sizeof(extack)); 8706 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8707 if (err && extack._msg) 8708 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8709 return err; 8710 } 8711 EXPORT_SYMBOL(dev_set_mtu); 8712 8713 /** 8714 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8715 * @dev: device 8716 * @new_len: new tx queue length 8717 */ 8718 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8719 { 8720 unsigned int orig_len = dev->tx_queue_len; 8721 int res; 8722 8723 if (new_len != (unsigned int)new_len) 8724 return -ERANGE; 8725 8726 if (new_len != orig_len) { 8727 dev->tx_queue_len = new_len; 8728 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8729 res = notifier_to_errno(res); 8730 if (res) 8731 goto err_rollback; 8732 res = dev_qdisc_change_tx_queue_len(dev); 8733 if (res) 8734 goto err_rollback; 8735 } 8736 8737 return 0; 8738 8739 err_rollback: 8740 netdev_err(dev, "refused to change device tx_queue_len\n"); 8741 dev->tx_queue_len = orig_len; 8742 return res; 8743 } 8744 8745 /** 8746 * dev_set_group - Change group this device belongs to 8747 * @dev: device 8748 * @new_group: group this device should belong to 8749 */ 8750 void dev_set_group(struct net_device *dev, int new_group) 8751 { 8752 dev->group = new_group; 8753 } 8754 8755 /** 8756 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8757 * @dev: device 8758 * @addr: new address 8759 * @extack: netlink extended ack 8760 */ 8761 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 8762 struct netlink_ext_ack *extack) 8763 { 8764 struct netdev_notifier_pre_changeaddr_info info = { 8765 .info.dev = dev, 8766 .info.extack = extack, 8767 .dev_addr = addr, 8768 }; 8769 int rc; 8770 8771 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 8772 return notifier_to_errno(rc); 8773 } 8774 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 8775 8776 /** 8777 * dev_set_mac_address - Change Media Access Control Address 8778 * @dev: device 8779 * @sa: new address 8780 * @extack: netlink extended ack 8781 * 8782 * Change the hardware (MAC) address of the device 8783 */ 8784 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 8785 struct netlink_ext_ack *extack) 8786 { 8787 const struct net_device_ops *ops = dev->netdev_ops; 8788 int err; 8789 8790 if (!ops->ndo_set_mac_address) 8791 return -EOPNOTSUPP; 8792 if (sa->sa_family != dev->type) 8793 return -EINVAL; 8794 if (!netif_device_present(dev)) 8795 return -ENODEV; 8796 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 8797 if (err) 8798 return err; 8799 err = ops->ndo_set_mac_address(dev, sa); 8800 if (err) 8801 return err; 8802 dev->addr_assign_type = NET_ADDR_SET; 8803 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 8804 add_device_randomness(dev->dev_addr, dev->addr_len); 8805 return 0; 8806 } 8807 EXPORT_SYMBOL(dev_set_mac_address); 8808 8809 static DECLARE_RWSEM(dev_addr_sem); 8810 8811 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 8812 struct netlink_ext_ack *extack) 8813 { 8814 int ret; 8815 8816 down_write(&dev_addr_sem); 8817 ret = dev_set_mac_address(dev, sa, extack); 8818 up_write(&dev_addr_sem); 8819 return ret; 8820 } 8821 EXPORT_SYMBOL(dev_set_mac_address_user); 8822 8823 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 8824 { 8825 size_t size = sizeof(sa->sa_data); 8826 struct net_device *dev; 8827 int ret = 0; 8828 8829 down_read(&dev_addr_sem); 8830 rcu_read_lock(); 8831 8832 dev = dev_get_by_name_rcu(net, dev_name); 8833 if (!dev) { 8834 ret = -ENODEV; 8835 goto unlock; 8836 } 8837 if (!dev->addr_len) 8838 memset(sa->sa_data, 0, size); 8839 else 8840 memcpy(sa->sa_data, dev->dev_addr, 8841 min_t(size_t, size, dev->addr_len)); 8842 sa->sa_family = dev->type; 8843 8844 unlock: 8845 rcu_read_unlock(); 8846 up_read(&dev_addr_sem); 8847 return ret; 8848 } 8849 EXPORT_SYMBOL(dev_get_mac_address); 8850 8851 /** 8852 * dev_change_carrier - Change device carrier 8853 * @dev: device 8854 * @new_carrier: new value 8855 * 8856 * Change device carrier 8857 */ 8858 int dev_change_carrier(struct net_device *dev, bool new_carrier) 8859 { 8860 const struct net_device_ops *ops = dev->netdev_ops; 8861 8862 if (!ops->ndo_change_carrier) 8863 return -EOPNOTSUPP; 8864 if (!netif_device_present(dev)) 8865 return -ENODEV; 8866 return ops->ndo_change_carrier(dev, new_carrier); 8867 } 8868 8869 /** 8870 * dev_get_phys_port_id - Get device physical port ID 8871 * @dev: device 8872 * @ppid: port ID 8873 * 8874 * Get device physical port ID 8875 */ 8876 int dev_get_phys_port_id(struct net_device *dev, 8877 struct netdev_phys_item_id *ppid) 8878 { 8879 const struct net_device_ops *ops = dev->netdev_ops; 8880 8881 if (!ops->ndo_get_phys_port_id) 8882 return -EOPNOTSUPP; 8883 return ops->ndo_get_phys_port_id(dev, ppid); 8884 } 8885 8886 /** 8887 * dev_get_phys_port_name - Get device physical port name 8888 * @dev: device 8889 * @name: port name 8890 * @len: limit of bytes to copy to name 8891 * 8892 * Get device physical port name 8893 */ 8894 int dev_get_phys_port_name(struct net_device *dev, 8895 char *name, size_t len) 8896 { 8897 const struct net_device_ops *ops = dev->netdev_ops; 8898 int err; 8899 8900 if (ops->ndo_get_phys_port_name) { 8901 err = ops->ndo_get_phys_port_name(dev, name, len); 8902 if (err != -EOPNOTSUPP) 8903 return err; 8904 } 8905 return devlink_compat_phys_port_name_get(dev, name, len); 8906 } 8907 8908 /** 8909 * dev_get_port_parent_id - Get the device's port parent identifier 8910 * @dev: network device 8911 * @ppid: pointer to a storage for the port's parent identifier 8912 * @recurse: allow/disallow recursion to lower devices 8913 * 8914 * Get the devices's port parent identifier 8915 */ 8916 int dev_get_port_parent_id(struct net_device *dev, 8917 struct netdev_phys_item_id *ppid, 8918 bool recurse) 8919 { 8920 const struct net_device_ops *ops = dev->netdev_ops; 8921 struct netdev_phys_item_id first = { }; 8922 struct net_device *lower_dev; 8923 struct list_head *iter; 8924 int err; 8925 8926 if (ops->ndo_get_port_parent_id) { 8927 err = ops->ndo_get_port_parent_id(dev, ppid); 8928 if (err != -EOPNOTSUPP) 8929 return err; 8930 } 8931 8932 err = devlink_compat_switch_id_get(dev, ppid); 8933 if (!recurse || err != -EOPNOTSUPP) 8934 return err; 8935 8936 netdev_for_each_lower_dev(dev, lower_dev, iter) { 8937 err = dev_get_port_parent_id(lower_dev, ppid, true); 8938 if (err) 8939 break; 8940 if (!first.id_len) 8941 first = *ppid; 8942 else if (memcmp(&first, ppid, sizeof(*ppid))) 8943 return -EOPNOTSUPP; 8944 } 8945 8946 return err; 8947 } 8948 EXPORT_SYMBOL(dev_get_port_parent_id); 8949 8950 /** 8951 * netdev_port_same_parent_id - Indicate if two network devices have 8952 * the same port parent identifier 8953 * @a: first network device 8954 * @b: second network device 8955 */ 8956 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 8957 { 8958 struct netdev_phys_item_id a_id = { }; 8959 struct netdev_phys_item_id b_id = { }; 8960 8961 if (dev_get_port_parent_id(a, &a_id, true) || 8962 dev_get_port_parent_id(b, &b_id, true)) 8963 return false; 8964 8965 return netdev_phys_item_id_same(&a_id, &b_id); 8966 } 8967 EXPORT_SYMBOL(netdev_port_same_parent_id); 8968 8969 /** 8970 * dev_change_proto_down - set carrier according to proto_down. 8971 * 8972 * @dev: device 8973 * @proto_down: new value 8974 */ 8975 int dev_change_proto_down(struct net_device *dev, bool proto_down) 8976 { 8977 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN)) 8978 return -EOPNOTSUPP; 8979 if (!netif_device_present(dev)) 8980 return -ENODEV; 8981 if (proto_down) 8982 netif_carrier_off(dev); 8983 else 8984 netif_carrier_on(dev); 8985 dev->proto_down = proto_down; 8986 return 0; 8987 } 8988 8989 /** 8990 * dev_change_proto_down_reason - proto down reason 8991 * 8992 * @dev: device 8993 * @mask: proto down mask 8994 * @value: proto down value 8995 */ 8996 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 8997 u32 value) 8998 { 8999 int b; 9000 9001 if (!mask) { 9002 dev->proto_down_reason = value; 9003 } else { 9004 for_each_set_bit(b, &mask, 32) { 9005 if (value & (1 << b)) 9006 dev->proto_down_reason |= BIT(b); 9007 else 9008 dev->proto_down_reason &= ~BIT(b); 9009 } 9010 } 9011 } 9012 9013 struct bpf_xdp_link { 9014 struct bpf_link link; 9015 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 9016 int flags; 9017 }; 9018 9019 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 9020 { 9021 if (flags & XDP_FLAGS_HW_MODE) 9022 return XDP_MODE_HW; 9023 if (flags & XDP_FLAGS_DRV_MODE) 9024 return XDP_MODE_DRV; 9025 if (flags & XDP_FLAGS_SKB_MODE) 9026 return XDP_MODE_SKB; 9027 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 9028 } 9029 9030 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 9031 { 9032 switch (mode) { 9033 case XDP_MODE_SKB: 9034 return generic_xdp_install; 9035 case XDP_MODE_DRV: 9036 case XDP_MODE_HW: 9037 return dev->netdev_ops->ndo_bpf; 9038 default: 9039 return NULL; 9040 } 9041 } 9042 9043 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9044 enum bpf_xdp_mode mode) 9045 { 9046 return dev->xdp_state[mode].link; 9047 } 9048 9049 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9050 enum bpf_xdp_mode mode) 9051 { 9052 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9053 9054 if (link) 9055 return link->link.prog; 9056 return dev->xdp_state[mode].prog; 9057 } 9058 9059 u8 dev_xdp_prog_count(struct net_device *dev) 9060 { 9061 u8 count = 0; 9062 int i; 9063 9064 for (i = 0; i < __MAX_XDP_MODE; i++) 9065 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9066 count++; 9067 return count; 9068 } 9069 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9070 9071 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9072 { 9073 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9074 9075 return prog ? prog->aux->id : 0; 9076 } 9077 9078 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9079 struct bpf_xdp_link *link) 9080 { 9081 dev->xdp_state[mode].link = link; 9082 dev->xdp_state[mode].prog = NULL; 9083 } 9084 9085 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9086 struct bpf_prog *prog) 9087 { 9088 dev->xdp_state[mode].link = NULL; 9089 dev->xdp_state[mode].prog = prog; 9090 } 9091 9092 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9093 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9094 u32 flags, struct bpf_prog *prog) 9095 { 9096 struct netdev_bpf xdp; 9097 int err; 9098 9099 memset(&xdp, 0, sizeof(xdp)); 9100 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9101 xdp.extack = extack; 9102 xdp.flags = flags; 9103 xdp.prog = prog; 9104 9105 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9106 * "moved" into driver), so they don't increment it on their own, but 9107 * they do decrement refcnt when program is detached or replaced. 9108 * Given net_device also owns link/prog, we need to bump refcnt here 9109 * to prevent drivers from underflowing it. 9110 */ 9111 if (prog) 9112 bpf_prog_inc(prog); 9113 err = bpf_op(dev, &xdp); 9114 if (err) { 9115 if (prog) 9116 bpf_prog_put(prog); 9117 return err; 9118 } 9119 9120 if (mode != XDP_MODE_HW) 9121 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9122 9123 return 0; 9124 } 9125 9126 static void dev_xdp_uninstall(struct net_device *dev) 9127 { 9128 struct bpf_xdp_link *link; 9129 struct bpf_prog *prog; 9130 enum bpf_xdp_mode mode; 9131 bpf_op_t bpf_op; 9132 9133 ASSERT_RTNL(); 9134 9135 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9136 prog = dev_xdp_prog(dev, mode); 9137 if (!prog) 9138 continue; 9139 9140 bpf_op = dev_xdp_bpf_op(dev, mode); 9141 if (!bpf_op) 9142 continue; 9143 9144 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9145 9146 /* auto-detach link from net device */ 9147 link = dev_xdp_link(dev, mode); 9148 if (link) 9149 link->dev = NULL; 9150 else 9151 bpf_prog_put(prog); 9152 9153 dev_xdp_set_link(dev, mode, NULL); 9154 } 9155 } 9156 9157 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9158 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9159 struct bpf_prog *old_prog, u32 flags) 9160 { 9161 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9162 struct bpf_prog *cur_prog; 9163 struct net_device *upper; 9164 struct list_head *iter; 9165 enum bpf_xdp_mode mode; 9166 bpf_op_t bpf_op; 9167 int err; 9168 9169 ASSERT_RTNL(); 9170 9171 /* either link or prog attachment, never both */ 9172 if (link && (new_prog || old_prog)) 9173 return -EINVAL; 9174 /* link supports only XDP mode flags */ 9175 if (link && (flags & ~XDP_FLAGS_MODES)) { 9176 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9177 return -EINVAL; 9178 } 9179 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9180 if (num_modes > 1) { 9181 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9182 return -EINVAL; 9183 } 9184 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9185 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9186 NL_SET_ERR_MSG(extack, 9187 "More than one program loaded, unset mode is ambiguous"); 9188 return -EINVAL; 9189 } 9190 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9191 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9192 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9193 return -EINVAL; 9194 } 9195 9196 mode = dev_xdp_mode(dev, flags); 9197 /* can't replace attached link */ 9198 if (dev_xdp_link(dev, mode)) { 9199 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9200 return -EBUSY; 9201 } 9202 9203 /* don't allow if an upper device already has a program */ 9204 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9205 if (dev_xdp_prog_count(upper) > 0) { 9206 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9207 return -EEXIST; 9208 } 9209 } 9210 9211 cur_prog = dev_xdp_prog(dev, mode); 9212 /* can't replace attached prog with link */ 9213 if (link && cur_prog) { 9214 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9215 return -EBUSY; 9216 } 9217 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9218 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9219 return -EEXIST; 9220 } 9221 9222 /* put effective new program into new_prog */ 9223 if (link) 9224 new_prog = link->link.prog; 9225 9226 if (new_prog) { 9227 bool offload = mode == XDP_MODE_HW; 9228 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9229 ? XDP_MODE_DRV : XDP_MODE_SKB; 9230 9231 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9232 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9233 return -EBUSY; 9234 } 9235 if (!offload && dev_xdp_prog(dev, other_mode)) { 9236 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 9237 return -EEXIST; 9238 } 9239 if (!offload && bpf_prog_is_dev_bound(new_prog->aux)) { 9240 NL_SET_ERR_MSG(extack, "Using device-bound program without HW_MODE flag is not supported"); 9241 return -EINVAL; 9242 } 9243 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 9244 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 9245 return -EINVAL; 9246 } 9247 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 9248 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 9249 return -EINVAL; 9250 } 9251 } 9252 9253 /* don't call drivers if the effective program didn't change */ 9254 if (new_prog != cur_prog) { 9255 bpf_op = dev_xdp_bpf_op(dev, mode); 9256 if (!bpf_op) { 9257 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 9258 return -EOPNOTSUPP; 9259 } 9260 9261 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 9262 if (err) 9263 return err; 9264 } 9265 9266 if (link) 9267 dev_xdp_set_link(dev, mode, link); 9268 else 9269 dev_xdp_set_prog(dev, mode, new_prog); 9270 if (cur_prog) 9271 bpf_prog_put(cur_prog); 9272 9273 return 0; 9274 } 9275 9276 static int dev_xdp_attach_link(struct net_device *dev, 9277 struct netlink_ext_ack *extack, 9278 struct bpf_xdp_link *link) 9279 { 9280 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 9281 } 9282 9283 static int dev_xdp_detach_link(struct net_device *dev, 9284 struct netlink_ext_ack *extack, 9285 struct bpf_xdp_link *link) 9286 { 9287 enum bpf_xdp_mode mode; 9288 bpf_op_t bpf_op; 9289 9290 ASSERT_RTNL(); 9291 9292 mode = dev_xdp_mode(dev, link->flags); 9293 if (dev_xdp_link(dev, mode) != link) 9294 return -EINVAL; 9295 9296 bpf_op = dev_xdp_bpf_op(dev, mode); 9297 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9298 dev_xdp_set_link(dev, mode, NULL); 9299 return 0; 9300 } 9301 9302 static void bpf_xdp_link_release(struct bpf_link *link) 9303 { 9304 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9305 9306 rtnl_lock(); 9307 9308 /* if racing with net_device's tear down, xdp_link->dev might be 9309 * already NULL, in which case link was already auto-detached 9310 */ 9311 if (xdp_link->dev) { 9312 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 9313 xdp_link->dev = NULL; 9314 } 9315 9316 rtnl_unlock(); 9317 } 9318 9319 static int bpf_xdp_link_detach(struct bpf_link *link) 9320 { 9321 bpf_xdp_link_release(link); 9322 return 0; 9323 } 9324 9325 static void bpf_xdp_link_dealloc(struct bpf_link *link) 9326 { 9327 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9328 9329 kfree(xdp_link); 9330 } 9331 9332 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 9333 struct seq_file *seq) 9334 { 9335 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9336 u32 ifindex = 0; 9337 9338 rtnl_lock(); 9339 if (xdp_link->dev) 9340 ifindex = xdp_link->dev->ifindex; 9341 rtnl_unlock(); 9342 9343 seq_printf(seq, "ifindex:\t%u\n", ifindex); 9344 } 9345 9346 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 9347 struct bpf_link_info *info) 9348 { 9349 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9350 u32 ifindex = 0; 9351 9352 rtnl_lock(); 9353 if (xdp_link->dev) 9354 ifindex = xdp_link->dev->ifindex; 9355 rtnl_unlock(); 9356 9357 info->xdp.ifindex = ifindex; 9358 return 0; 9359 } 9360 9361 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 9362 struct bpf_prog *old_prog) 9363 { 9364 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9365 enum bpf_xdp_mode mode; 9366 bpf_op_t bpf_op; 9367 int err = 0; 9368 9369 rtnl_lock(); 9370 9371 /* link might have been auto-released already, so fail */ 9372 if (!xdp_link->dev) { 9373 err = -ENOLINK; 9374 goto out_unlock; 9375 } 9376 9377 if (old_prog && link->prog != old_prog) { 9378 err = -EPERM; 9379 goto out_unlock; 9380 } 9381 old_prog = link->prog; 9382 if (old_prog->type != new_prog->type || 9383 old_prog->expected_attach_type != new_prog->expected_attach_type) { 9384 err = -EINVAL; 9385 goto out_unlock; 9386 } 9387 9388 if (old_prog == new_prog) { 9389 /* no-op, don't disturb drivers */ 9390 bpf_prog_put(new_prog); 9391 goto out_unlock; 9392 } 9393 9394 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 9395 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9396 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9397 xdp_link->flags, new_prog); 9398 if (err) 9399 goto out_unlock; 9400 9401 old_prog = xchg(&link->prog, new_prog); 9402 bpf_prog_put(old_prog); 9403 9404 out_unlock: 9405 rtnl_unlock(); 9406 return err; 9407 } 9408 9409 static const struct bpf_link_ops bpf_xdp_link_lops = { 9410 .release = bpf_xdp_link_release, 9411 .dealloc = bpf_xdp_link_dealloc, 9412 .detach = bpf_xdp_link_detach, 9413 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9414 .fill_link_info = bpf_xdp_link_fill_link_info, 9415 .update_prog = bpf_xdp_link_update, 9416 }; 9417 9418 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9419 { 9420 struct net *net = current->nsproxy->net_ns; 9421 struct bpf_link_primer link_primer; 9422 struct bpf_xdp_link *link; 9423 struct net_device *dev; 9424 int err, fd; 9425 9426 rtnl_lock(); 9427 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9428 if (!dev) { 9429 rtnl_unlock(); 9430 return -EINVAL; 9431 } 9432 9433 link = kzalloc(sizeof(*link), GFP_USER); 9434 if (!link) { 9435 err = -ENOMEM; 9436 goto unlock; 9437 } 9438 9439 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9440 link->dev = dev; 9441 link->flags = attr->link_create.flags; 9442 9443 err = bpf_link_prime(&link->link, &link_primer); 9444 if (err) { 9445 kfree(link); 9446 goto unlock; 9447 } 9448 9449 err = dev_xdp_attach_link(dev, NULL, link); 9450 rtnl_unlock(); 9451 9452 if (err) { 9453 link->dev = NULL; 9454 bpf_link_cleanup(&link_primer); 9455 goto out_put_dev; 9456 } 9457 9458 fd = bpf_link_settle(&link_primer); 9459 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9460 dev_put(dev); 9461 return fd; 9462 9463 unlock: 9464 rtnl_unlock(); 9465 9466 out_put_dev: 9467 dev_put(dev); 9468 return err; 9469 } 9470 9471 /** 9472 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9473 * @dev: device 9474 * @extack: netlink extended ack 9475 * @fd: new program fd or negative value to clear 9476 * @expected_fd: old program fd that userspace expects to replace or clear 9477 * @flags: xdp-related flags 9478 * 9479 * Set or clear a bpf program for a device 9480 */ 9481 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9482 int fd, int expected_fd, u32 flags) 9483 { 9484 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9485 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9486 int err; 9487 9488 ASSERT_RTNL(); 9489 9490 if (fd >= 0) { 9491 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9492 mode != XDP_MODE_SKB); 9493 if (IS_ERR(new_prog)) 9494 return PTR_ERR(new_prog); 9495 } 9496 9497 if (expected_fd >= 0) { 9498 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9499 mode != XDP_MODE_SKB); 9500 if (IS_ERR(old_prog)) { 9501 err = PTR_ERR(old_prog); 9502 old_prog = NULL; 9503 goto err_out; 9504 } 9505 } 9506 9507 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9508 9509 err_out: 9510 if (err && new_prog) 9511 bpf_prog_put(new_prog); 9512 if (old_prog) 9513 bpf_prog_put(old_prog); 9514 return err; 9515 } 9516 9517 /** 9518 * dev_new_index - allocate an ifindex 9519 * @net: the applicable net namespace 9520 * 9521 * Returns a suitable unique value for a new device interface 9522 * number. The caller must hold the rtnl semaphore or the 9523 * dev_base_lock to be sure it remains unique. 9524 */ 9525 static int dev_new_index(struct net *net) 9526 { 9527 int ifindex = net->ifindex; 9528 9529 for (;;) { 9530 if (++ifindex <= 0) 9531 ifindex = 1; 9532 if (!__dev_get_by_index(net, ifindex)) 9533 return net->ifindex = ifindex; 9534 } 9535 } 9536 9537 /* Delayed registration/unregisteration */ 9538 LIST_HEAD(net_todo_list); 9539 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9540 9541 static void net_set_todo(struct net_device *dev) 9542 { 9543 list_add_tail(&dev->todo_list, &net_todo_list); 9544 atomic_inc(&dev_net(dev)->dev_unreg_count); 9545 } 9546 9547 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9548 struct net_device *upper, netdev_features_t features) 9549 { 9550 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9551 netdev_features_t feature; 9552 int feature_bit; 9553 9554 for_each_netdev_feature(upper_disables, feature_bit) { 9555 feature = __NETIF_F_BIT(feature_bit); 9556 if (!(upper->wanted_features & feature) 9557 && (features & feature)) { 9558 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9559 &feature, upper->name); 9560 features &= ~feature; 9561 } 9562 } 9563 9564 return features; 9565 } 9566 9567 static void netdev_sync_lower_features(struct net_device *upper, 9568 struct net_device *lower, netdev_features_t features) 9569 { 9570 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9571 netdev_features_t feature; 9572 int feature_bit; 9573 9574 for_each_netdev_feature(upper_disables, feature_bit) { 9575 feature = __NETIF_F_BIT(feature_bit); 9576 if (!(features & feature) && (lower->features & feature)) { 9577 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9578 &feature, lower->name); 9579 lower->wanted_features &= ~feature; 9580 __netdev_update_features(lower); 9581 9582 if (unlikely(lower->features & feature)) 9583 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9584 &feature, lower->name); 9585 else 9586 netdev_features_change(lower); 9587 } 9588 } 9589 } 9590 9591 static netdev_features_t netdev_fix_features(struct net_device *dev, 9592 netdev_features_t features) 9593 { 9594 /* Fix illegal checksum combinations */ 9595 if ((features & NETIF_F_HW_CSUM) && 9596 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9597 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9598 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9599 } 9600 9601 /* TSO requires that SG is present as well. */ 9602 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9603 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9604 features &= ~NETIF_F_ALL_TSO; 9605 } 9606 9607 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9608 !(features & NETIF_F_IP_CSUM)) { 9609 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9610 features &= ~NETIF_F_TSO; 9611 features &= ~NETIF_F_TSO_ECN; 9612 } 9613 9614 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9615 !(features & NETIF_F_IPV6_CSUM)) { 9616 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9617 features &= ~NETIF_F_TSO6; 9618 } 9619 9620 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9621 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9622 features &= ~NETIF_F_TSO_MANGLEID; 9623 9624 /* TSO ECN requires that TSO is present as well. */ 9625 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9626 features &= ~NETIF_F_TSO_ECN; 9627 9628 /* Software GSO depends on SG. */ 9629 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9630 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9631 features &= ~NETIF_F_GSO; 9632 } 9633 9634 /* GSO partial features require GSO partial be set */ 9635 if ((features & dev->gso_partial_features) && 9636 !(features & NETIF_F_GSO_PARTIAL)) { 9637 netdev_dbg(dev, 9638 "Dropping partially supported GSO features since no GSO partial.\n"); 9639 features &= ~dev->gso_partial_features; 9640 } 9641 9642 if (!(features & NETIF_F_RXCSUM)) { 9643 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9644 * successfully merged by hardware must also have the 9645 * checksum verified by hardware. If the user does not 9646 * want to enable RXCSUM, logically, we should disable GRO_HW. 9647 */ 9648 if (features & NETIF_F_GRO_HW) { 9649 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9650 features &= ~NETIF_F_GRO_HW; 9651 } 9652 } 9653 9654 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9655 if (features & NETIF_F_RXFCS) { 9656 if (features & NETIF_F_LRO) { 9657 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9658 features &= ~NETIF_F_LRO; 9659 } 9660 9661 if (features & NETIF_F_GRO_HW) { 9662 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9663 features &= ~NETIF_F_GRO_HW; 9664 } 9665 } 9666 9667 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9668 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9669 features &= ~NETIF_F_LRO; 9670 } 9671 9672 if (features & NETIF_F_HW_TLS_TX) { 9673 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9674 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9675 bool hw_csum = features & NETIF_F_HW_CSUM; 9676 9677 if (!ip_csum && !hw_csum) { 9678 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9679 features &= ~NETIF_F_HW_TLS_TX; 9680 } 9681 } 9682 9683 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9684 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9685 features &= ~NETIF_F_HW_TLS_RX; 9686 } 9687 9688 return features; 9689 } 9690 9691 int __netdev_update_features(struct net_device *dev) 9692 { 9693 struct net_device *upper, *lower; 9694 netdev_features_t features; 9695 struct list_head *iter; 9696 int err = -1; 9697 9698 ASSERT_RTNL(); 9699 9700 features = netdev_get_wanted_features(dev); 9701 9702 if (dev->netdev_ops->ndo_fix_features) 9703 features = dev->netdev_ops->ndo_fix_features(dev, features); 9704 9705 /* driver might be less strict about feature dependencies */ 9706 features = netdev_fix_features(dev, features); 9707 9708 /* some features can't be enabled if they're off on an upper device */ 9709 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9710 features = netdev_sync_upper_features(dev, upper, features); 9711 9712 if (dev->features == features) 9713 goto sync_lower; 9714 9715 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9716 &dev->features, &features); 9717 9718 if (dev->netdev_ops->ndo_set_features) 9719 err = dev->netdev_ops->ndo_set_features(dev, features); 9720 else 9721 err = 0; 9722 9723 if (unlikely(err < 0)) { 9724 netdev_err(dev, 9725 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9726 err, &features, &dev->features); 9727 /* return non-0 since some features might have changed and 9728 * it's better to fire a spurious notification than miss it 9729 */ 9730 return -1; 9731 } 9732 9733 sync_lower: 9734 /* some features must be disabled on lower devices when disabled 9735 * on an upper device (think: bonding master or bridge) 9736 */ 9737 netdev_for_each_lower_dev(dev, lower, iter) 9738 netdev_sync_lower_features(dev, lower, features); 9739 9740 if (!err) { 9741 netdev_features_t diff = features ^ dev->features; 9742 9743 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 9744 /* udp_tunnel_{get,drop}_rx_info both need 9745 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 9746 * device, or they won't do anything. 9747 * Thus we need to update dev->features 9748 * *before* calling udp_tunnel_get_rx_info, 9749 * but *after* calling udp_tunnel_drop_rx_info. 9750 */ 9751 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 9752 dev->features = features; 9753 udp_tunnel_get_rx_info(dev); 9754 } else { 9755 udp_tunnel_drop_rx_info(dev); 9756 } 9757 } 9758 9759 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 9760 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 9761 dev->features = features; 9762 err |= vlan_get_rx_ctag_filter_info(dev); 9763 } else { 9764 vlan_drop_rx_ctag_filter_info(dev); 9765 } 9766 } 9767 9768 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 9769 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 9770 dev->features = features; 9771 err |= vlan_get_rx_stag_filter_info(dev); 9772 } else { 9773 vlan_drop_rx_stag_filter_info(dev); 9774 } 9775 } 9776 9777 dev->features = features; 9778 } 9779 9780 return err < 0 ? 0 : 1; 9781 } 9782 9783 /** 9784 * netdev_update_features - recalculate device features 9785 * @dev: the device to check 9786 * 9787 * Recalculate dev->features set and send notifications if it 9788 * has changed. Should be called after driver or hardware dependent 9789 * conditions might have changed that influence the features. 9790 */ 9791 void netdev_update_features(struct net_device *dev) 9792 { 9793 if (__netdev_update_features(dev)) 9794 netdev_features_change(dev); 9795 } 9796 EXPORT_SYMBOL(netdev_update_features); 9797 9798 /** 9799 * netdev_change_features - recalculate device features 9800 * @dev: the device to check 9801 * 9802 * Recalculate dev->features set and send notifications even 9803 * if they have not changed. Should be called instead of 9804 * netdev_update_features() if also dev->vlan_features might 9805 * have changed to allow the changes to be propagated to stacked 9806 * VLAN devices. 9807 */ 9808 void netdev_change_features(struct net_device *dev) 9809 { 9810 __netdev_update_features(dev); 9811 netdev_features_change(dev); 9812 } 9813 EXPORT_SYMBOL(netdev_change_features); 9814 9815 /** 9816 * netif_stacked_transfer_operstate - transfer operstate 9817 * @rootdev: the root or lower level device to transfer state from 9818 * @dev: the device to transfer operstate to 9819 * 9820 * Transfer operational state from root to device. This is normally 9821 * called when a stacking relationship exists between the root 9822 * device and the device(a leaf device). 9823 */ 9824 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 9825 struct net_device *dev) 9826 { 9827 if (rootdev->operstate == IF_OPER_DORMANT) 9828 netif_dormant_on(dev); 9829 else 9830 netif_dormant_off(dev); 9831 9832 if (rootdev->operstate == IF_OPER_TESTING) 9833 netif_testing_on(dev); 9834 else 9835 netif_testing_off(dev); 9836 9837 if (netif_carrier_ok(rootdev)) 9838 netif_carrier_on(dev); 9839 else 9840 netif_carrier_off(dev); 9841 } 9842 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 9843 9844 static int netif_alloc_rx_queues(struct net_device *dev) 9845 { 9846 unsigned int i, count = dev->num_rx_queues; 9847 struct netdev_rx_queue *rx; 9848 size_t sz = count * sizeof(*rx); 9849 int err = 0; 9850 9851 BUG_ON(count < 1); 9852 9853 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9854 if (!rx) 9855 return -ENOMEM; 9856 9857 dev->_rx = rx; 9858 9859 for (i = 0; i < count; i++) { 9860 rx[i].dev = dev; 9861 9862 /* XDP RX-queue setup */ 9863 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 9864 if (err < 0) 9865 goto err_rxq_info; 9866 } 9867 return 0; 9868 9869 err_rxq_info: 9870 /* Rollback successful reg's and free other resources */ 9871 while (i--) 9872 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 9873 kvfree(dev->_rx); 9874 dev->_rx = NULL; 9875 return err; 9876 } 9877 9878 static void netif_free_rx_queues(struct net_device *dev) 9879 { 9880 unsigned int i, count = dev->num_rx_queues; 9881 9882 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 9883 if (!dev->_rx) 9884 return; 9885 9886 for (i = 0; i < count; i++) 9887 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 9888 9889 kvfree(dev->_rx); 9890 } 9891 9892 static void netdev_init_one_queue(struct net_device *dev, 9893 struct netdev_queue *queue, void *_unused) 9894 { 9895 /* Initialize queue lock */ 9896 spin_lock_init(&queue->_xmit_lock); 9897 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 9898 queue->xmit_lock_owner = -1; 9899 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 9900 queue->dev = dev; 9901 #ifdef CONFIG_BQL 9902 dql_init(&queue->dql, HZ); 9903 #endif 9904 } 9905 9906 static void netif_free_tx_queues(struct net_device *dev) 9907 { 9908 kvfree(dev->_tx); 9909 } 9910 9911 static int netif_alloc_netdev_queues(struct net_device *dev) 9912 { 9913 unsigned int count = dev->num_tx_queues; 9914 struct netdev_queue *tx; 9915 size_t sz = count * sizeof(*tx); 9916 9917 if (count < 1 || count > 0xffff) 9918 return -EINVAL; 9919 9920 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9921 if (!tx) 9922 return -ENOMEM; 9923 9924 dev->_tx = tx; 9925 9926 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 9927 spin_lock_init(&dev->tx_global_lock); 9928 9929 return 0; 9930 } 9931 9932 void netif_tx_stop_all_queues(struct net_device *dev) 9933 { 9934 unsigned int i; 9935 9936 for (i = 0; i < dev->num_tx_queues; i++) { 9937 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 9938 9939 netif_tx_stop_queue(txq); 9940 } 9941 } 9942 EXPORT_SYMBOL(netif_tx_stop_all_queues); 9943 9944 /** 9945 * register_netdevice() - register a network device 9946 * @dev: device to register 9947 * 9948 * Take a prepared network device structure and make it externally accessible. 9949 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 9950 * Callers must hold the rtnl lock - you may want register_netdev() 9951 * instead of this. 9952 */ 9953 int register_netdevice(struct net_device *dev) 9954 { 9955 int ret; 9956 struct net *net = dev_net(dev); 9957 9958 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 9959 NETDEV_FEATURE_COUNT); 9960 BUG_ON(dev_boot_phase); 9961 ASSERT_RTNL(); 9962 9963 might_sleep(); 9964 9965 /* When net_device's are persistent, this will be fatal. */ 9966 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 9967 BUG_ON(!net); 9968 9969 ret = ethtool_check_ops(dev->ethtool_ops); 9970 if (ret) 9971 return ret; 9972 9973 spin_lock_init(&dev->addr_list_lock); 9974 netdev_set_addr_lockdep_class(dev); 9975 9976 ret = dev_get_valid_name(net, dev, dev->name); 9977 if (ret < 0) 9978 goto out; 9979 9980 ret = -ENOMEM; 9981 dev->name_node = netdev_name_node_head_alloc(dev); 9982 if (!dev->name_node) 9983 goto out; 9984 9985 /* Init, if this function is available */ 9986 if (dev->netdev_ops->ndo_init) { 9987 ret = dev->netdev_ops->ndo_init(dev); 9988 if (ret) { 9989 if (ret > 0) 9990 ret = -EIO; 9991 goto err_free_name; 9992 } 9993 } 9994 9995 if (((dev->hw_features | dev->features) & 9996 NETIF_F_HW_VLAN_CTAG_FILTER) && 9997 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 9998 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 9999 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 10000 ret = -EINVAL; 10001 goto err_uninit; 10002 } 10003 10004 ret = -EBUSY; 10005 if (!dev->ifindex) 10006 dev->ifindex = dev_new_index(net); 10007 else if (__dev_get_by_index(net, dev->ifindex)) 10008 goto err_uninit; 10009 10010 /* Transfer changeable features to wanted_features and enable 10011 * software offloads (GSO and GRO). 10012 */ 10013 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 10014 dev->features |= NETIF_F_SOFT_FEATURES; 10015 10016 if (dev->udp_tunnel_nic_info) { 10017 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10018 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10019 } 10020 10021 dev->wanted_features = dev->features & dev->hw_features; 10022 10023 if (!(dev->flags & IFF_LOOPBACK)) 10024 dev->hw_features |= NETIF_F_NOCACHE_COPY; 10025 10026 /* If IPv4 TCP segmentation offload is supported we should also 10027 * allow the device to enable segmenting the frame with the option 10028 * of ignoring a static IP ID value. This doesn't enable the 10029 * feature itself but allows the user to enable it later. 10030 */ 10031 if (dev->hw_features & NETIF_F_TSO) 10032 dev->hw_features |= NETIF_F_TSO_MANGLEID; 10033 if (dev->vlan_features & NETIF_F_TSO) 10034 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10035 if (dev->mpls_features & NETIF_F_TSO) 10036 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10037 if (dev->hw_enc_features & NETIF_F_TSO) 10038 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10039 10040 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10041 */ 10042 dev->vlan_features |= NETIF_F_HIGHDMA; 10043 10044 /* Make NETIF_F_SG inheritable to tunnel devices. 10045 */ 10046 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10047 10048 /* Make NETIF_F_SG inheritable to MPLS. 10049 */ 10050 dev->mpls_features |= NETIF_F_SG; 10051 10052 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10053 ret = notifier_to_errno(ret); 10054 if (ret) 10055 goto err_uninit; 10056 10057 ret = netdev_register_kobject(dev); 10058 write_lock(&dev_base_lock); 10059 dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED; 10060 write_unlock(&dev_base_lock); 10061 if (ret) 10062 goto err_uninit; 10063 10064 __netdev_update_features(dev); 10065 10066 /* 10067 * Default initial state at registry is that the 10068 * device is present. 10069 */ 10070 10071 set_bit(__LINK_STATE_PRESENT, &dev->state); 10072 10073 linkwatch_init_dev(dev); 10074 10075 dev_init_scheduler(dev); 10076 10077 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10078 list_netdevice(dev); 10079 10080 add_device_randomness(dev->dev_addr, dev->addr_len); 10081 10082 /* If the device has permanent device address, driver should 10083 * set dev_addr and also addr_assign_type should be set to 10084 * NET_ADDR_PERM (default value). 10085 */ 10086 if (dev->addr_assign_type == NET_ADDR_PERM) 10087 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10088 10089 /* Notify protocols, that a new device appeared. */ 10090 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10091 ret = notifier_to_errno(ret); 10092 if (ret) { 10093 /* Expect explicit free_netdev() on failure */ 10094 dev->needs_free_netdev = false; 10095 unregister_netdevice_queue(dev, NULL); 10096 goto out; 10097 } 10098 /* 10099 * Prevent userspace races by waiting until the network 10100 * device is fully setup before sending notifications. 10101 */ 10102 if (!dev->rtnl_link_ops || 10103 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10104 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); 10105 10106 out: 10107 return ret; 10108 10109 err_uninit: 10110 if (dev->netdev_ops->ndo_uninit) 10111 dev->netdev_ops->ndo_uninit(dev); 10112 if (dev->priv_destructor) 10113 dev->priv_destructor(dev); 10114 err_free_name: 10115 netdev_name_node_free(dev->name_node); 10116 goto out; 10117 } 10118 EXPORT_SYMBOL(register_netdevice); 10119 10120 /** 10121 * init_dummy_netdev - init a dummy network device for NAPI 10122 * @dev: device to init 10123 * 10124 * This takes a network device structure and initialize the minimum 10125 * amount of fields so it can be used to schedule NAPI polls without 10126 * registering a full blown interface. This is to be used by drivers 10127 * that need to tie several hardware interfaces to a single NAPI 10128 * poll scheduler due to HW limitations. 10129 */ 10130 int init_dummy_netdev(struct net_device *dev) 10131 { 10132 /* Clear everything. Note we don't initialize spinlocks 10133 * are they aren't supposed to be taken by any of the 10134 * NAPI code and this dummy netdev is supposed to be 10135 * only ever used for NAPI polls 10136 */ 10137 memset(dev, 0, sizeof(struct net_device)); 10138 10139 /* make sure we BUG if trying to hit standard 10140 * register/unregister code path 10141 */ 10142 dev->reg_state = NETREG_DUMMY; 10143 10144 /* NAPI wants this */ 10145 INIT_LIST_HEAD(&dev->napi_list); 10146 10147 /* a dummy interface is started by default */ 10148 set_bit(__LINK_STATE_PRESENT, &dev->state); 10149 set_bit(__LINK_STATE_START, &dev->state); 10150 10151 /* napi_busy_loop stats accounting wants this */ 10152 dev_net_set(dev, &init_net); 10153 10154 /* Note : We dont allocate pcpu_refcnt for dummy devices, 10155 * because users of this 'device' dont need to change 10156 * its refcount. 10157 */ 10158 10159 return 0; 10160 } 10161 EXPORT_SYMBOL_GPL(init_dummy_netdev); 10162 10163 10164 /** 10165 * register_netdev - register a network device 10166 * @dev: device to register 10167 * 10168 * Take a completed network device structure and add it to the kernel 10169 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 10170 * chain. 0 is returned on success. A negative errno code is returned 10171 * on a failure to set up the device, or if the name is a duplicate. 10172 * 10173 * This is a wrapper around register_netdevice that takes the rtnl semaphore 10174 * and expands the device name if you passed a format string to 10175 * alloc_netdev. 10176 */ 10177 int register_netdev(struct net_device *dev) 10178 { 10179 int err; 10180 10181 if (rtnl_lock_killable()) 10182 return -EINTR; 10183 err = register_netdevice(dev); 10184 rtnl_unlock(); 10185 return err; 10186 } 10187 EXPORT_SYMBOL(register_netdev); 10188 10189 int netdev_refcnt_read(const struct net_device *dev) 10190 { 10191 #ifdef CONFIG_PCPU_DEV_REFCNT 10192 int i, refcnt = 0; 10193 10194 for_each_possible_cpu(i) 10195 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 10196 return refcnt; 10197 #else 10198 return refcount_read(&dev->dev_refcnt); 10199 #endif 10200 } 10201 EXPORT_SYMBOL(netdev_refcnt_read); 10202 10203 int netdev_unregister_timeout_secs __read_mostly = 10; 10204 10205 #define WAIT_REFS_MIN_MSECS 1 10206 #define WAIT_REFS_MAX_MSECS 250 10207 /** 10208 * netdev_wait_allrefs_any - wait until all references are gone. 10209 * @list: list of net_devices to wait on 10210 * 10211 * This is called when unregistering network devices. 10212 * 10213 * Any protocol or device that holds a reference should register 10214 * for netdevice notification, and cleanup and put back the 10215 * reference if they receive an UNREGISTER event. 10216 * We can get stuck here if buggy protocols don't correctly 10217 * call dev_put. 10218 */ 10219 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 10220 { 10221 unsigned long rebroadcast_time, warning_time; 10222 struct net_device *dev; 10223 int wait = 0; 10224 10225 rebroadcast_time = warning_time = jiffies; 10226 10227 list_for_each_entry(dev, list, todo_list) 10228 if (netdev_refcnt_read(dev) == 1) 10229 return dev; 10230 10231 while (true) { 10232 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 10233 rtnl_lock(); 10234 10235 /* Rebroadcast unregister notification */ 10236 list_for_each_entry(dev, list, todo_list) 10237 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10238 10239 __rtnl_unlock(); 10240 rcu_barrier(); 10241 rtnl_lock(); 10242 10243 list_for_each_entry(dev, list, todo_list) 10244 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 10245 &dev->state)) { 10246 /* We must not have linkwatch events 10247 * pending on unregister. If this 10248 * happens, we simply run the queue 10249 * unscheduled, resulting in a noop 10250 * for this device. 10251 */ 10252 linkwatch_run_queue(); 10253 break; 10254 } 10255 10256 __rtnl_unlock(); 10257 10258 rebroadcast_time = jiffies; 10259 } 10260 10261 if (!wait) { 10262 rcu_barrier(); 10263 wait = WAIT_REFS_MIN_MSECS; 10264 } else { 10265 msleep(wait); 10266 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 10267 } 10268 10269 list_for_each_entry(dev, list, todo_list) 10270 if (netdev_refcnt_read(dev) == 1) 10271 return dev; 10272 10273 if (time_after(jiffies, warning_time + 10274 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 10275 list_for_each_entry(dev, list, todo_list) { 10276 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 10277 dev->name, netdev_refcnt_read(dev)); 10278 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 10279 } 10280 10281 warning_time = jiffies; 10282 } 10283 } 10284 } 10285 10286 /* The sequence is: 10287 * 10288 * rtnl_lock(); 10289 * ... 10290 * register_netdevice(x1); 10291 * register_netdevice(x2); 10292 * ... 10293 * unregister_netdevice(y1); 10294 * unregister_netdevice(y2); 10295 * ... 10296 * rtnl_unlock(); 10297 * free_netdev(y1); 10298 * free_netdev(y2); 10299 * 10300 * We are invoked by rtnl_unlock(). 10301 * This allows us to deal with problems: 10302 * 1) We can delete sysfs objects which invoke hotplug 10303 * without deadlocking with linkwatch via keventd. 10304 * 2) Since we run with the RTNL semaphore not held, we can sleep 10305 * safely in order to wait for the netdev refcnt to drop to zero. 10306 * 10307 * We must not return until all unregister events added during 10308 * the interval the lock was held have been completed. 10309 */ 10310 void netdev_run_todo(void) 10311 { 10312 struct net_device *dev, *tmp; 10313 struct list_head list; 10314 #ifdef CONFIG_LOCKDEP 10315 struct list_head unlink_list; 10316 10317 list_replace_init(&net_unlink_list, &unlink_list); 10318 10319 while (!list_empty(&unlink_list)) { 10320 struct net_device *dev = list_first_entry(&unlink_list, 10321 struct net_device, 10322 unlink_list); 10323 list_del_init(&dev->unlink_list); 10324 dev->nested_level = dev->lower_level - 1; 10325 } 10326 #endif 10327 10328 /* Snapshot list, allow later requests */ 10329 list_replace_init(&net_todo_list, &list); 10330 10331 __rtnl_unlock(); 10332 10333 /* Wait for rcu callbacks to finish before next phase */ 10334 if (!list_empty(&list)) 10335 rcu_barrier(); 10336 10337 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 10338 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 10339 netdev_WARN(dev, "run_todo but not unregistering\n"); 10340 list_del(&dev->todo_list); 10341 continue; 10342 } 10343 10344 write_lock(&dev_base_lock); 10345 dev->reg_state = NETREG_UNREGISTERED; 10346 write_unlock(&dev_base_lock); 10347 linkwatch_forget_dev(dev); 10348 } 10349 10350 while (!list_empty(&list)) { 10351 dev = netdev_wait_allrefs_any(&list); 10352 list_del(&dev->todo_list); 10353 10354 /* paranoia */ 10355 BUG_ON(netdev_refcnt_read(dev) != 1); 10356 BUG_ON(!list_empty(&dev->ptype_all)); 10357 BUG_ON(!list_empty(&dev->ptype_specific)); 10358 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 10359 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 10360 10361 if (dev->priv_destructor) 10362 dev->priv_destructor(dev); 10363 if (dev->needs_free_netdev) 10364 free_netdev(dev); 10365 10366 if (atomic_dec_and_test(&dev_net(dev)->dev_unreg_count)) 10367 wake_up(&netdev_unregistering_wq); 10368 10369 /* Free network device */ 10370 kobject_put(&dev->dev.kobj); 10371 } 10372 } 10373 10374 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 10375 * all the same fields in the same order as net_device_stats, with only 10376 * the type differing, but rtnl_link_stats64 may have additional fields 10377 * at the end for newer counters. 10378 */ 10379 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 10380 const struct net_device_stats *netdev_stats) 10381 { 10382 #if BITS_PER_LONG == 64 10383 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats)); 10384 memcpy(stats64, netdev_stats, sizeof(*netdev_stats)); 10385 /* zero out counters that only exist in rtnl_link_stats64 */ 10386 memset((char *)stats64 + sizeof(*netdev_stats), 0, 10387 sizeof(*stats64) - sizeof(*netdev_stats)); 10388 #else 10389 size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long); 10390 const unsigned long *src = (const unsigned long *)netdev_stats; 10391 u64 *dst = (u64 *)stats64; 10392 10393 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 10394 for (i = 0; i < n; i++) 10395 dst[i] = src[i]; 10396 /* zero out counters that only exist in rtnl_link_stats64 */ 10397 memset((char *)stats64 + n * sizeof(u64), 0, 10398 sizeof(*stats64) - n * sizeof(u64)); 10399 #endif 10400 } 10401 EXPORT_SYMBOL(netdev_stats_to_stats64); 10402 10403 struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) 10404 { 10405 struct net_device_core_stats __percpu *p; 10406 10407 p = alloc_percpu_gfp(struct net_device_core_stats, 10408 GFP_ATOMIC | __GFP_NOWARN); 10409 10410 if (p && cmpxchg(&dev->core_stats, NULL, p)) 10411 free_percpu(p); 10412 10413 /* This READ_ONCE() pairs with the cmpxchg() above */ 10414 return READ_ONCE(dev->core_stats); 10415 } 10416 EXPORT_SYMBOL(netdev_core_stats_alloc); 10417 10418 /** 10419 * dev_get_stats - get network device statistics 10420 * @dev: device to get statistics from 10421 * @storage: place to store stats 10422 * 10423 * Get network statistics from device. Return @storage. 10424 * The device driver may provide its own method by setting 10425 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10426 * otherwise the internal statistics structure is used. 10427 */ 10428 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10429 struct rtnl_link_stats64 *storage) 10430 { 10431 const struct net_device_ops *ops = dev->netdev_ops; 10432 const struct net_device_core_stats __percpu *p; 10433 10434 if (ops->ndo_get_stats64) { 10435 memset(storage, 0, sizeof(*storage)); 10436 ops->ndo_get_stats64(dev, storage); 10437 } else if (ops->ndo_get_stats) { 10438 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10439 } else { 10440 netdev_stats_to_stats64(storage, &dev->stats); 10441 } 10442 10443 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10444 p = READ_ONCE(dev->core_stats); 10445 if (p) { 10446 const struct net_device_core_stats *core_stats; 10447 int i; 10448 10449 for_each_possible_cpu(i) { 10450 core_stats = per_cpu_ptr(p, i); 10451 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 10452 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 10453 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 10454 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 10455 } 10456 } 10457 return storage; 10458 } 10459 EXPORT_SYMBOL(dev_get_stats); 10460 10461 /** 10462 * dev_fetch_sw_netstats - get per-cpu network device statistics 10463 * @s: place to store stats 10464 * @netstats: per-cpu network stats to read from 10465 * 10466 * Read per-cpu network statistics and populate the related fields in @s. 10467 */ 10468 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10469 const struct pcpu_sw_netstats __percpu *netstats) 10470 { 10471 int cpu; 10472 10473 for_each_possible_cpu(cpu) { 10474 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 10475 const struct pcpu_sw_netstats *stats; 10476 unsigned int start; 10477 10478 stats = per_cpu_ptr(netstats, cpu); 10479 do { 10480 start = u64_stats_fetch_begin_irq(&stats->syncp); 10481 rx_packets = u64_stats_read(&stats->rx_packets); 10482 rx_bytes = u64_stats_read(&stats->rx_bytes); 10483 tx_packets = u64_stats_read(&stats->tx_packets); 10484 tx_bytes = u64_stats_read(&stats->tx_bytes); 10485 } while (u64_stats_fetch_retry_irq(&stats->syncp, start)); 10486 10487 s->rx_packets += rx_packets; 10488 s->rx_bytes += rx_bytes; 10489 s->tx_packets += tx_packets; 10490 s->tx_bytes += tx_bytes; 10491 } 10492 } 10493 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10494 10495 /** 10496 * dev_get_tstats64 - ndo_get_stats64 implementation 10497 * @dev: device to get statistics from 10498 * @s: place to store stats 10499 * 10500 * Populate @s from dev->stats and dev->tstats. Can be used as 10501 * ndo_get_stats64() callback. 10502 */ 10503 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10504 { 10505 netdev_stats_to_stats64(s, &dev->stats); 10506 dev_fetch_sw_netstats(s, dev->tstats); 10507 } 10508 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10509 10510 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10511 { 10512 struct netdev_queue *queue = dev_ingress_queue(dev); 10513 10514 #ifdef CONFIG_NET_CLS_ACT 10515 if (queue) 10516 return queue; 10517 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10518 if (!queue) 10519 return NULL; 10520 netdev_init_one_queue(dev, queue, NULL); 10521 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10522 queue->qdisc_sleeping = &noop_qdisc; 10523 rcu_assign_pointer(dev->ingress_queue, queue); 10524 #endif 10525 return queue; 10526 } 10527 10528 static const struct ethtool_ops default_ethtool_ops; 10529 10530 void netdev_set_default_ethtool_ops(struct net_device *dev, 10531 const struct ethtool_ops *ops) 10532 { 10533 if (dev->ethtool_ops == &default_ethtool_ops) 10534 dev->ethtool_ops = ops; 10535 } 10536 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10537 10538 void netdev_freemem(struct net_device *dev) 10539 { 10540 char *addr = (char *)dev - dev->padded; 10541 10542 kvfree(addr); 10543 } 10544 10545 /** 10546 * alloc_netdev_mqs - allocate network device 10547 * @sizeof_priv: size of private data to allocate space for 10548 * @name: device name format string 10549 * @name_assign_type: origin of device name 10550 * @setup: callback to initialize device 10551 * @txqs: the number of TX subqueues to allocate 10552 * @rxqs: the number of RX subqueues to allocate 10553 * 10554 * Allocates a struct net_device with private data area for driver use 10555 * and performs basic initialization. Also allocates subqueue structs 10556 * for each queue on the device. 10557 */ 10558 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10559 unsigned char name_assign_type, 10560 void (*setup)(struct net_device *), 10561 unsigned int txqs, unsigned int rxqs) 10562 { 10563 struct net_device *dev; 10564 unsigned int alloc_size; 10565 struct net_device *p; 10566 10567 BUG_ON(strlen(name) >= sizeof(dev->name)); 10568 10569 if (txqs < 1) { 10570 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10571 return NULL; 10572 } 10573 10574 if (rxqs < 1) { 10575 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10576 return NULL; 10577 } 10578 10579 alloc_size = sizeof(struct net_device); 10580 if (sizeof_priv) { 10581 /* ensure 32-byte alignment of private area */ 10582 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10583 alloc_size += sizeof_priv; 10584 } 10585 /* ensure 32-byte alignment of whole construct */ 10586 alloc_size += NETDEV_ALIGN - 1; 10587 10588 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10589 if (!p) 10590 return NULL; 10591 10592 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10593 dev->padded = (char *)dev - (char *)p; 10594 10595 ref_tracker_dir_init(&dev->refcnt_tracker, 128); 10596 #ifdef CONFIG_PCPU_DEV_REFCNT 10597 dev->pcpu_refcnt = alloc_percpu(int); 10598 if (!dev->pcpu_refcnt) 10599 goto free_dev; 10600 __dev_hold(dev); 10601 #else 10602 refcount_set(&dev->dev_refcnt, 1); 10603 #endif 10604 10605 if (dev_addr_init(dev)) 10606 goto free_pcpu; 10607 10608 dev_mc_init(dev); 10609 dev_uc_init(dev); 10610 10611 dev_net_set(dev, &init_net); 10612 10613 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 10614 dev->gso_max_segs = GSO_MAX_SEGS; 10615 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 10616 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 10617 dev->tso_max_segs = TSO_MAX_SEGS; 10618 dev->upper_level = 1; 10619 dev->lower_level = 1; 10620 #ifdef CONFIG_LOCKDEP 10621 dev->nested_level = 0; 10622 INIT_LIST_HEAD(&dev->unlink_list); 10623 #endif 10624 10625 INIT_LIST_HEAD(&dev->napi_list); 10626 INIT_LIST_HEAD(&dev->unreg_list); 10627 INIT_LIST_HEAD(&dev->close_list); 10628 INIT_LIST_HEAD(&dev->link_watch_list); 10629 INIT_LIST_HEAD(&dev->adj_list.upper); 10630 INIT_LIST_HEAD(&dev->adj_list.lower); 10631 INIT_LIST_HEAD(&dev->ptype_all); 10632 INIT_LIST_HEAD(&dev->ptype_specific); 10633 INIT_LIST_HEAD(&dev->net_notifier_list); 10634 #ifdef CONFIG_NET_SCHED 10635 hash_init(dev->qdisc_hash); 10636 #endif 10637 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 10638 setup(dev); 10639 10640 if (!dev->tx_queue_len) { 10641 dev->priv_flags |= IFF_NO_QUEUE; 10642 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 10643 } 10644 10645 dev->num_tx_queues = txqs; 10646 dev->real_num_tx_queues = txqs; 10647 if (netif_alloc_netdev_queues(dev)) 10648 goto free_all; 10649 10650 dev->num_rx_queues = rxqs; 10651 dev->real_num_rx_queues = rxqs; 10652 if (netif_alloc_rx_queues(dev)) 10653 goto free_all; 10654 10655 strcpy(dev->name, name); 10656 dev->name_assign_type = name_assign_type; 10657 dev->group = INIT_NETDEV_GROUP; 10658 if (!dev->ethtool_ops) 10659 dev->ethtool_ops = &default_ethtool_ops; 10660 10661 nf_hook_netdev_init(dev); 10662 10663 return dev; 10664 10665 free_all: 10666 free_netdev(dev); 10667 return NULL; 10668 10669 free_pcpu: 10670 #ifdef CONFIG_PCPU_DEV_REFCNT 10671 free_percpu(dev->pcpu_refcnt); 10672 free_dev: 10673 #endif 10674 netdev_freemem(dev); 10675 return NULL; 10676 } 10677 EXPORT_SYMBOL(alloc_netdev_mqs); 10678 10679 /** 10680 * free_netdev - free network device 10681 * @dev: device 10682 * 10683 * This function does the last stage of destroying an allocated device 10684 * interface. The reference to the device object is released. If this 10685 * is the last reference then it will be freed.Must be called in process 10686 * context. 10687 */ 10688 void free_netdev(struct net_device *dev) 10689 { 10690 struct napi_struct *p, *n; 10691 10692 might_sleep(); 10693 10694 /* When called immediately after register_netdevice() failed the unwind 10695 * handling may still be dismantling the device. Handle that case by 10696 * deferring the free. 10697 */ 10698 if (dev->reg_state == NETREG_UNREGISTERING) { 10699 ASSERT_RTNL(); 10700 dev->needs_free_netdev = true; 10701 return; 10702 } 10703 10704 netif_free_tx_queues(dev); 10705 netif_free_rx_queues(dev); 10706 10707 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 10708 10709 /* Flush device addresses */ 10710 dev_addr_flush(dev); 10711 10712 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 10713 netif_napi_del(p); 10714 10715 ref_tracker_dir_exit(&dev->refcnt_tracker); 10716 #ifdef CONFIG_PCPU_DEV_REFCNT 10717 free_percpu(dev->pcpu_refcnt); 10718 dev->pcpu_refcnt = NULL; 10719 #endif 10720 free_percpu(dev->core_stats); 10721 dev->core_stats = NULL; 10722 free_percpu(dev->xdp_bulkq); 10723 dev->xdp_bulkq = NULL; 10724 10725 /* Compatibility with error handling in drivers */ 10726 if (dev->reg_state == NETREG_UNINITIALIZED) { 10727 netdev_freemem(dev); 10728 return; 10729 } 10730 10731 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 10732 dev->reg_state = NETREG_RELEASED; 10733 10734 /* will free via device release */ 10735 put_device(&dev->dev); 10736 } 10737 EXPORT_SYMBOL(free_netdev); 10738 10739 /** 10740 * synchronize_net - Synchronize with packet receive processing 10741 * 10742 * Wait for packets currently being received to be done. 10743 * Does not block later packets from starting. 10744 */ 10745 void synchronize_net(void) 10746 { 10747 might_sleep(); 10748 if (rtnl_is_locked()) 10749 synchronize_rcu_expedited(); 10750 else 10751 synchronize_rcu(); 10752 } 10753 EXPORT_SYMBOL(synchronize_net); 10754 10755 /** 10756 * unregister_netdevice_queue - remove device from the kernel 10757 * @dev: device 10758 * @head: list 10759 * 10760 * This function shuts down a device interface and removes it 10761 * from the kernel tables. 10762 * If head not NULL, device is queued to be unregistered later. 10763 * 10764 * Callers must hold the rtnl semaphore. You may want 10765 * unregister_netdev() instead of this. 10766 */ 10767 10768 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 10769 { 10770 ASSERT_RTNL(); 10771 10772 if (head) { 10773 list_move_tail(&dev->unreg_list, head); 10774 } else { 10775 LIST_HEAD(single); 10776 10777 list_add(&dev->unreg_list, &single); 10778 unregister_netdevice_many(&single); 10779 } 10780 } 10781 EXPORT_SYMBOL(unregister_netdevice_queue); 10782 10783 /** 10784 * unregister_netdevice_many - unregister many devices 10785 * @head: list of devices 10786 * 10787 * Note: As most callers use a stack allocated list_head, 10788 * we force a list_del() to make sure stack wont be corrupted later. 10789 */ 10790 void unregister_netdevice_many(struct list_head *head) 10791 { 10792 struct net_device *dev, *tmp; 10793 LIST_HEAD(close_head); 10794 10795 BUG_ON(dev_boot_phase); 10796 ASSERT_RTNL(); 10797 10798 if (list_empty(head)) 10799 return; 10800 10801 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 10802 /* Some devices call without registering 10803 * for initialization unwind. Remove those 10804 * devices and proceed with the remaining. 10805 */ 10806 if (dev->reg_state == NETREG_UNINITIALIZED) { 10807 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 10808 dev->name, dev); 10809 10810 WARN_ON(1); 10811 list_del(&dev->unreg_list); 10812 continue; 10813 } 10814 dev->dismantle = true; 10815 BUG_ON(dev->reg_state != NETREG_REGISTERED); 10816 } 10817 10818 /* If device is running, close it first. */ 10819 list_for_each_entry(dev, head, unreg_list) 10820 list_add_tail(&dev->close_list, &close_head); 10821 dev_close_many(&close_head, true); 10822 10823 list_for_each_entry(dev, head, unreg_list) { 10824 /* And unlink it from device chain. */ 10825 write_lock(&dev_base_lock); 10826 unlist_netdevice(dev, false); 10827 dev->reg_state = NETREG_UNREGISTERING; 10828 write_unlock(&dev_base_lock); 10829 } 10830 flush_all_backlogs(); 10831 10832 synchronize_net(); 10833 10834 list_for_each_entry(dev, head, unreg_list) { 10835 struct sk_buff *skb = NULL; 10836 10837 /* Shutdown queueing discipline. */ 10838 dev_shutdown(dev); 10839 10840 dev_xdp_uninstall(dev); 10841 10842 netdev_offload_xstats_disable_all(dev); 10843 10844 /* Notify protocols, that we are about to destroy 10845 * this device. They should clean all the things. 10846 */ 10847 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10848 10849 if (!dev->rtnl_link_ops || 10850 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10851 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 10852 GFP_KERNEL, NULL, 0); 10853 10854 /* 10855 * Flush the unicast and multicast chains 10856 */ 10857 dev_uc_flush(dev); 10858 dev_mc_flush(dev); 10859 10860 netdev_name_node_alt_flush(dev); 10861 netdev_name_node_free(dev->name_node); 10862 10863 if (dev->netdev_ops->ndo_uninit) 10864 dev->netdev_ops->ndo_uninit(dev); 10865 10866 if (skb) 10867 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL); 10868 10869 /* Notifier chain MUST detach us all upper devices. */ 10870 WARN_ON(netdev_has_any_upper_dev(dev)); 10871 WARN_ON(netdev_has_any_lower_dev(dev)); 10872 10873 /* Remove entries from kobject tree */ 10874 netdev_unregister_kobject(dev); 10875 #ifdef CONFIG_XPS 10876 /* Remove XPS queueing entries */ 10877 netif_reset_xps_queues_gt(dev, 0); 10878 #endif 10879 } 10880 10881 synchronize_net(); 10882 10883 list_for_each_entry(dev, head, unreg_list) { 10884 netdev_put(dev, &dev->dev_registered_tracker); 10885 net_set_todo(dev); 10886 } 10887 10888 list_del(head); 10889 } 10890 EXPORT_SYMBOL(unregister_netdevice_many); 10891 10892 /** 10893 * unregister_netdev - remove device from the kernel 10894 * @dev: device 10895 * 10896 * This function shuts down a device interface and removes it 10897 * from the kernel tables. 10898 * 10899 * This is just a wrapper for unregister_netdevice that takes 10900 * the rtnl semaphore. In general you want to use this and not 10901 * unregister_netdevice. 10902 */ 10903 void unregister_netdev(struct net_device *dev) 10904 { 10905 rtnl_lock(); 10906 unregister_netdevice(dev); 10907 rtnl_unlock(); 10908 } 10909 EXPORT_SYMBOL(unregister_netdev); 10910 10911 /** 10912 * __dev_change_net_namespace - move device to different nethost namespace 10913 * @dev: device 10914 * @net: network namespace 10915 * @pat: If not NULL name pattern to try if the current device name 10916 * is already taken in the destination network namespace. 10917 * @new_ifindex: If not zero, specifies device index in the target 10918 * namespace. 10919 * 10920 * This function shuts down a device interface and moves it 10921 * to a new network namespace. On success 0 is returned, on 10922 * a failure a netagive errno code is returned. 10923 * 10924 * Callers must hold the rtnl semaphore. 10925 */ 10926 10927 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 10928 const char *pat, int new_ifindex) 10929 { 10930 struct net *net_old = dev_net(dev); 10931 int err, new_nsid; 10932 10933 ASSERT_RTNL(); 10934 10935 /* Don't allow namespace local devices to be moved. */ 10936 err = -EINVAL; 10937 if (dev->features & NETIF_F_NETNS_LOCAL) 10938 goto out; 10939 10940 /* Ensure the device has been registrered */ 10941 if (dev->reg_state != NETREG_REGISTERED) 10942 goto out; 10943 10944 /* Get out if there is nothing todo */ 10945 err = 0; 10946 if (net_eq(net_old, net)) 10947 goto out; 10948 10949 /* Pick the destination device name, and ensure 10950 * we can use it in the destination network namespace. 10951 */ 10952 err = -EEXIST; 10953 if (netdev_name_in_use(net, dev->name)) { 10954 /* We get here if we can't use the current device name */ 10955 if (!pat) 10956 goto out; 10957 err = dev_get_valid_name(net, dev, pat); 10958 if (err < 0) 10959 goto out; 10960 } 10961 10962 /* Check that new_ifindex isn't used yet. */ 10963 err = -EBUSY; 10964 if (new_ifindex && __dev_get_by_index(net, new_ifindex)) 10965 goto out; 10966 10967 /* 10968 * And now a mini version of register_netdevice unregister_netdevice. 10969 */ 10970 10971 /* If device is running close it first. */ 10972 dev_close(dev); 10973 10974 /* And unlink it from device chain */ 10975 unlist_netdevice(dev, true); 10976 10977 synchronize_net(); 10978 10979 /* Shutdown queueing discipline. */ 10980 dev_shutdown(dev); 10981 10982 /* Notify protocols, that we are about to destroy 10983 * this device. They should clean all the things. 10984 * 10985 * Note that dev->reg_state stays at NETREG_REGISTERED. 10986 * This is wanted because this way 8021q and macvlan know 10987 * the device is just moving and can keep their slaves up. 10988 */ 10989 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10990 rcu_barrier(); 10991 10992 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 10993 /* If there is an ifindex conflict assign a new one */ 10994 if (!new_ifindex) { 10995 if (__dev_get_by_index(net, dev->ifindex)) 10996 new_ifindex = dev_new_index(net); 10997 else 10998 new_ifindex = dev->ifindex; 10999 } 11000 11001 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 11002 new_ifindex); 11003 11004 /* 11005 * Flush the unicast and multicast chains 11006 */ 11007 dev_uc_flush(dev); 11008 dev_mc_flush(dev); 11009 11010 /* Send a netdev-removed uevent to the old namespace */ 11011 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 11012 netdev_adjacent_del_links(dev); 11013 11014 /* Move per-net netdevice notifiers that are following the netdevice */ 11015 move_netdevice_notifiers_dev_net(dev, net); 11016 11017 /* Actually switch the network namespace */ 11018 dev_net_set(dev, net); 11019 dev->ifindex = new_ifindex; 11020 11021 /* Send a netdev-add uevent to the new namespace */ 11022 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 11023 netdev_adjacent_add_links(dev); 11024 11025 /* Fixup kobjects */ 11026 err = device_rename(&dev->dev, dev->name); 11027 WARN_ON(err); 11028 11029 /* Adapt owner in case owning user namespace of target network 11030 * namespace is different from the original one. 11031 */ 11032 err = netdev_change_owner(dev, net_old, net); 11033 WARN_ON(err); 11034 11035 /* Add the device back in the hashes */ 11036 list_netdevice(dev); 11037 11038 /* Notify protocols, that a new device appeared. */ 11039 call_netdevice_notifiers(NETDEV_REGISTER, dev); 11040 11041 /* 11042 * Prevent userspace races by waiting until the network 11043 * device is fully setup before sending notifications. 11044 */ 11045 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); 11046 11047 synchronize_net(); 11048 err = 0; 11049 out: 11050 return err; 11051 } 11052 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 11053 11054 static int dev_cpu_dead(unsigned int oldcpu) 11055 { 11056 struct sk_buff **list_skb; 11057 struct sk_buff *skb; 11058 unsigned int cpu; 11059 struct softnet_data *sd, *oldsd, *remsd = NULL; 11060 11061 local_irq_disable(); 11062 cpu = smp_processor_id(); 11063 sd = &per_cpu(softnet_data, cpu); 11064 oldsd = &per_cpu(softnet_data, oldcpu); 11065 11066 /* Find end of our completion_queue. */ 11067 list_skb = &sd->completion_queue; 11068 while (*list_skb) 11069 list_skb = &(*list_skb)->next; 11070 /* Append completion queue from offline CPU. */ 11071 *list_skb = oldsd->completion_queue; 11072 oldsd->completion_queue = NULL; 11073 11074 /* Append output queue from offline CPU. */ 11075 if (oldsd->output_queue) { 11076 *sd->output_queue_tailp = oldsd->output_queue; 11077 sd->output_queue_tailp = oldsd->output_queue_tailp; 11078 oldsd->output_queue = NULL; 11079 oldsd->output_queue_tailp = &oldsd->output_queue; 11080 } 11081 /* Append NAPI poll list from offline CPU, with one exception : 11082 * process_backlog() must be called by cpu owning percpu backlog. 11083 * We properly handle process_queue & input_pkt_queue later. 11084 */ 11085 while (!list_empty(&oldsd->poll_list)) { 11086 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 11087 struct napi_struct, 11088 poll_list); 11089 11090 list_del_init(&napi->poll_list); 11091 if (napi->poll == process_backlog) 11092 napi->state = 0; 11093 else 11094 ____napi_schedule(sd, napi); 11095 } 11096 11097 raise_softirq_irqoff(NET_TX_SOFTIRQ); 11098 local_irq_enable(); 11099 11100 #ifdef CONFIG_RPS 11101 remsd = oldsd->rps_ipi_list; 11102 oldsd->rps_ipi_list = NULL; 11103 #endif 11104 /* send out pending IPI's on offline CPU */ 11105 net_rps_send_ipi(remsd); 11106 11107 /* Process offline CPU's input_pkt_queue */ 11108 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 11109 netif_rx(skb); 11110 input_queue_head_incr(oldsd); 11111 } 11112 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 11113 netif_rx(skb); 11114 input_queue_head_incr(oldsd); 11115 } 11116 11117 return 0; 11118 } 11119 11120 /** 11121 * netdev_increment_features - increment feature set by one 11122 * @all: current feature set 11123 * @one: new feature set 11124 * @mask: mask feature set 11125 * 11126 * Computes a new feature set after adding a device with feature set 11127 * @one to the master device with current feature set @all. Will not 11128 * enable anything that is off in @mask. Returns the new feature set. 11129 */ 11130 netdev_features_t netdev_increment_features(netdev_features_t all, 11131 netdev_features_t one, netdev_features_t mask) 11132 { 11133 if (mask & NETIF_F_HW_CSUM) 11134 mask |= NETIF_F_CSUM_MASK; 11135 mask |= NETIF_F_VLAN_CHALLENGED; 11136 11137 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 11138 all &= one | ~NETIF_F_ALL_FOR_ALL; 11139 11140 /* If one device supports hw checksumming, set for all. */ 11141 if (all & NETIF_F_HW_CSUM) 11142 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 11143 11144 return all; 11145 } 11146 EXPORT_SYMBOL(netdev_increment_features); 11147 11148 static struct hlist_head * __net_init netdev_create_hash(void) 11149 { 11150 int i; 11151 struct hlist_head *hash; 11152 11153 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 11154 if (hash != NULL) 11155 for (i = 0; i < NETDEV_HASHENTRIES; i++) 11156 INIT_HLIST_HEAD(&hash[i]); 11157 11158 return hash; 11159 } 11160 11161 /* Initialize per network namespace state */ 11162 static int __net_init netdev_init(struct net *net) 11163 { 11164 BUILD_BUG_ON(GRO_HASH_BUCKETS > 11165 8 * sizeof_field(struct napi_struct, gro_bitmask)); 11166 11167 INIT_LIST_HEAD(&net->dev_base_head); 11168 11169 net->dev_name_head = netdev_create_hash(); 11170 if (net->dev_name_head == NULL) 11171 goto err_name; 11172 11173 net->dev_index_head = netdev_create_hash(); 11174 if (net->dev_index_head == NULL) 11175 goto err_idx; 11176 11177 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 11178 11179 return 0; 11180 11181 err_idx: 11182 kfree(net->dev_name_head); 11183 err_name: 11184 return -ENOMEM; 11185 } 11186 11187 /** 11188 * netdev_drivername - network driver for the device 11189 * @dev: network device 11190 * 11191 * Determine network driver for device. 11192 */ 11193 const char *netdev_drivername(const struct net_device *dev) 11194 { 11195 const struct device_driver *driver; 11196 const struct device *parent; 11197 const char *empty = ""; 11198 11199 parent = dev->dev.parent; 11200 if (!parent) 11201 return empty; 11202 11203 driver = parent->driver; 11204 if (driver && driver->name) 11205 return driver->name; 11206 return empty; 11207 } 11208 11209 static void __netdev_printk(const char *level, const struct net_device *dev, 11210 struct va_format *vaf) 11211 { 11212 if (dev && dev->dev.parent) { 11213 dev_printk_emit(level[1] - '0', 11214 dev->dev.parent, 11215 "%s %s %s%s: %pV", 11216 dev_driver_string(dev->dev.parent), 11217 dev_name(dev->dev.parent), 11218 netdev_name(dev), netdev_reg_state(dev), 11219 vaf); 11220 } else if (dev) { 11221 printk("%s%s%s: %pV", 11222 level, netdev_name(dev), netdev_reg_state(dev), vaf); 11223 } else { 11224 printk("%s(NULL net_device): %pV", level, vaf); 11225 } 11226 } 11227 11228 void netdev_printk(const char *level, const struct net_device *dev, 11229 const char *format, ...) 11230 { 11231 struct va_format vaf; 11232 va_list args; 11233 11234 va_start(args, format); 11235 11236 vaf.fmt = format; 11237 vaf.va = &args; 11238 11239 __netdev_printk(level, dev, &vaf); 11240 11241 va_end(args); 11242 } 11243 EXPORT_SYMBOL(netdev_printk); 11244 11245 #define define_netdev_printk_level(func, level) \ 11246 void func(const struct net_device *dev, const char *fmt, ...) \ 11247 { \ 11248 struct va_format vaf; \ 11249 va_list args; \ 11250 \ 11251 va_start(args, fmt); \ 11252 \ 11253 vaf.fmt = fmt; \ 11254 vaf.va = &args; \ 11255 \ 11256 __netdev_printk(level, dev, &vaf); \ 11257 \ 11258 va_end(args); \ 11259 } \ 11260 EXPORT_SYMBOL(func); 11261 11262 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 11263 define_netdev_printk_level(netdev_alert, KERN_ALERT); 11264 define_netdev_printk_level(netdev_crit, KERN_CRIT); 11265 define_netdev_printk_level(netdev_err, KERN_ERR); 11266 define_netdev_printk_level(netdev_warn, KERN_WARNING); 11267 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 11268 define_netdev_printk_level(netdev_info, KERN_INFO); 11269 11270 static void __net_exit netdev_exit(struct net *net) 11271 { 11272 kfree(net->dev_name_head); 11273 kfree(net->dev_index_head); 11274 if (net != &init_net) 11275 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 11276 } 11277 11278 static struct pernet_operations __net_initdata netdev_net_ops = { 11279 .init = netdev_init, 11280 .exit = netdev_exit, 11281 }; 11282 11283 static void __net_exit default_device_exit_net(struct net *net) 11284 { 11285 struct net_device *dev, *aux; 11286 /* 11287 * Push all migratable network devices back to the 11288 * initial network namespace 11289 */ 11290 ASSERT_RTNL(); 11291 for_each_netdev_safe(net, dev, aux) { 11292 int err; 11293 char fb_name[IFNAMSIZ]; 11294 11295 /* Ignore unmoveable devices (i.e. loopback) */ 11296 if (dev->features & NETIF_F_NETNS_LOCAL) 11297 continue; 11298 11299 /* Leave virtual devices for the generic cleanup */ 11300 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 11301 continue; 11302 11303 /* Push remaining network devices to init_net */ 11304 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 11305 if (netdev_name_in_use(&init_net, fb_name)) 11306 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 11307 err = dev_change_net_namespace(dev, &init_net, fb_name); 11308 if (err) { 11309 pr_emerg("%s: failed to move %s to init_net: %d\n", 11310 __func__, dev->name, err); 11311 BUG(); 11312 } 11313 } 11314 } 11315 11316 static void __net_exit default_device_exit_batch(struct list_head *net_list) 11317 { 11318 /* At exit all network devices most be removed from a network 11319 * namespace. Do this in the reverse order of registration. 11320 * Do this across as many network namespaces as possible to 11321 * improve batching efficiency. 11322 */ 11323 struct net_device *dev; 11324 struct net *net; 11325 LIST_HEAD(dev_kill_list); 11326 11327 rtnl_lock(); 11328 list_for_each_entry(net, net_list, exit_list) { 11329 default_device_exit_net(net); 11330 cond_resched(); 11331 } 11332 11333 list_for_each_entry(net, net_list, exit_list) { 11334 for_each_netdev_reverse(net, dev) { 11335 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 11336 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 11337 else 11338 unregister_netdevice_queue(dev, &dev_kill_list); 11339 } 11340 } 11341 unregister_netdevice_many(&dev_kill_list); 11342 rtnl_unlock(); 11343 } 11344 11345 static struct pernet_operations __net_initdata default_device_ops = { 11346 .exit_batch = default_device_exit_batch, 11347 }; 11348 11349 /* 11350 * Initialize the DEV module. At boot time this walks the device list and 11351 * unhooks any devices that fail to initialise (normally hardware not 11352 * present) and leaves us with a valid list of present and active devices. 11353 * 11354 */ 11355 11356 /* 11357 * This is called single threaded during boot, so no need 11358 * to take the rtnl semaphore. 11359 */ 11360 static int __init net_dev_init(void) 11361 { 11362 int i, rc = -ENOMEM; 11363 11364 BUG_ON(!dev_boot_phase); 11365 11366 if (dev_proc_init()) 11367 goto out; 11368 11369 if (netdev_kobject_init()) 11370 goto out; 11371 11372 INIT_LIST_HEAD(&ptype_all); 11373 for (i = 0; i < PTYPE_HASH_SIZE; i++) 11374 INIT_LIST_HEAD(&ptype_base[i]); 11375 11376 if (register_pernet_subsys(&netdev_net_ops)) 11377 goto out; 11378 11379 /* 11380 * Initialise the packet receive queues. 11381 */ 11382 11383 for_each_possible_cpu(i) { 11384 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 11385 struct softnet_data *sd = &per_cpu(softnet_data, i); 11386 11387 INIT_WORK(flush, flush_backlog); 11388 11389 skb_queue_head_init(&sd->input_pkt_queue); 11390 skb_queue_head_init(&sd->process_queue); 11391 #ifdef CONFIG_XFRM_OFFLOAD 11392 skb_queue_head_init(&sd->xfrm_backlog); 11393 #endif 11394 INIT_LIST_HEAD(&sd->poll_list); 11395 sd->output_queue_tailp = &sd->output_queue; 11396 #ifdef CONFIG_RPS 11397 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11398 sd->cpu = i; 11399 #endif 11400 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 11401 spin_lock_init(&sd->defer_lock); 11402 11403 init_gro_hash(&sd->backlog); 11404 sd->backlog.poll = process_backlog; 11405 sd->backlog.weight = weight_p; 11406 } 11407 11408 dev_boot_phase = 0; 11409 11410 /* The loopback device is special if any other network devices 11411 * is present in a network namespace the loopback device must 11412 * be present. Since we now dynamically allocate and free the 11413 * loopback device ensure this invariant is maintained by 11414 * keeping the loopback device as the first device on the 11415 * list of network devices. Ensuring the loopback devices 11416 * is the first device that appears and the last network device 11417 * that disappears. 11418 */ 11419 if (register_pernet_device(&loopback_net_ops)) 11420 goto out; 11421 11422 if (register_pernet_device(&default_device_ops)) 11423 goto out; 11424 11425 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11426 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11427 11428 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11429 NULL, dev_cpu_dead); 11430 WARN_ON(rc < 0); 11431 rc = 0; 11432 out: 11433 return rc; 11434 } 11435 11436 subsys_initcall(net_dev_init); 11437