1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * NET3 Protocol independent device support routines. 4 * 5 * Derived from the non IP parts of dev.c 1.0.19 6 * Authors: Ross Biro 7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 8 * Mark Evans, <evansmp@uhura.aston.ac.uk> 9 * 10 * Additional Authors: 11 * Florian la Roche <rzsfl@rz.uni-sb.de> 12 * Alan Cox <gw4pts@gw4pts.ampr.org> 13 * David Hinds <dahinds@users.sourceforge.net> 14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 15 * Adam Sulmicki <adam@cfar.umd.edu> 16 * Pekka Riikonen <priikone@poesidon.pspt.fi> 17 * 18 * Changes: 19 * D.J. Barrow : Fixed bug where dev->refcnt gets set 20 * to 2 if register_netdev gets called 21 * before net_dev_init & also removed a 22 * few lines of code in the process. 23 * Alan Cox : device private ioctl copies fields back. 24 * Alan Cox : Transmit queue code does relevant 25 * stunts to keep the queue safe. 26 * Alan Cox : Fixed double lock. 27 * Alan Cox : Fixed promisc NULL pointer trap 28 * ???????? : Support the full private ioctl range 29 * Alan Cox : Moved ioctl permission check into 30 * drivers 31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 32 * Alan Cox : 100 backlog just doesn't cut it when 33 * you start doing multicast video 8) 34 * Alan Cox : Rewrote net_bh and list manager. 35 * Alan Cox : Fix ETH_P_ALL echoback lengths. 36 * Alan Cox : Took out transmit every packet pass 37 * Saved a few bytes in the ioctl handler 38 * Alan Cox : Network driver sets packet type before 39 * calling netif_rx. Saves a function 40 * call a packet. 41 * Alan Cox : Hashed net_bh() 42 * Richard Kooijman: Timestamp fixes. 43 * Alan Cox : Wrong field in SIOCGIFDSTADDR 44 * Alan Cox : Device lock protection. 45 * Alan Cox : Fixed nasty side effect of device close 46 * changes. 47 * Rudi Cilibrasi : Pass the right thing to 48 * set_mac_address() 49 * Dave Miller : 32bit quantity for the device lock to 50 * make it work out on a Sparc. 51 * Bjorn Ekwall : Added KERNELD hack. 52 * Alan Cox : Cleaned up the backlog initialise. 53 * Craig Metz : SIOCGIFCONF fix if space for under 54 * 1 device. 55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 56 * is no device open function. 57 * Andi Kleen : Fix error reporting for SIOCGIFCONF 58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 59 * Cyrus Durgin : Cleaned for KMOD 60 * Adam Sulmicki : Bug Fix : Network Device Unload 61 * A network device unload needs to purge 62 * the backlog queue. 63 * Paul Rusty Russell : SIOCSIFNAME 64 * Pekka Riikonen : Netdev boot-time settings code 65 * Andrew Morton : Make unregister_netdevice wait 66 * indefinitely on dev->refcnt 67 * J Hadi Salim : - Backlog queue sampling 68 * - netif_rx() feedback 69 */ 70 71 #include <linux/uaccess.h> 72 #include <linux/bitmap.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/isolation.h> 81 #include <linux/sched/mm.h> 82 #include <linux/smpboot.h> 83 #include <linux/mutex.h> 84 #include <linux/rwsem.h> 85 #include <linux/string.h> 86 #include <linux/mm.h> 87 #include <linux/socket.h> 88 #include <linux/sockios.h> 89 #include <linux/errno.h> 90 #include <linux/interrupt.h> 91 #include <linux/if_ether.h> 92 #include <linux/netdevice.h> 93 #include <linux/etherdevice.h> 94 #include <linux/ethtool.h> 95 #include <linux/skbuff.h> 96 #include <linux/kthread.h> 97 #include <linux/bpf.h> 98 #include <linux/bpf_trace.h> 99 #include <net/net_namespace.h> 100 #include <net/sock.h> 101 #include <net/busy_poll.h> 102 #include <linux/rtnetlink.h> 103 #include <linux/stat.h> 104 #include <net/dsa.h> 105 #include <net/dst.h> 106 #include <net/dst_metadata.h> 107 #include <net/gro.h> 108 #include <net/pkt_sched.h> 109 #include <net/pkt_cls.h> 110 #include <net/checksum.h> 111 #include <net/xfrm.h> 112 #include <net/tcx.h> 113 #include <linux/highmem.h> 114 #include <linux/init.h> 115 #include <linux/module.h> 116 #include <linux/netpoll.h> 117 #include <linux/rcupdate.h> 118 #include <linux/delay.h> 119 #include <net/iw_handler.h> 120 #include <asm/current.h> 121 #include <linux/audit.h> 122 #include <linux/dmaengine.h> 123 #include <linux/err.h> 124 #include <linux/ctype.h> 125 #include <linux/if_arp.h> 126 #include <linux/if_vlan.h> 127 #include <linux/ip.h> 128 #include <net/ip.h> 129 #include <net/mpls.h> 130 #include <linux/ipv6.h> 131 #include <linux/in.h> 132 #include <linux/jhash.h> 133 #include <linux/random.h> 134 #include <trace/events/napi.h> 135 #include <trace/events/net.h> 136 #include <trace/events/skb.h> 137 #include <trace/events/qdisc.h> 138 #include <trace/events/xdp.h> 139 #include <linux/inetdevice.h> 140 #include <linux/cpu_rmap.h> 141 #include <linux/static_key.h> 142 #include <linux/hashtable.h> 143 #include <linux/vmalloc.h> 144 #include <linux/if_macvlan.h> 145 #include <linux/errqueue.h> 146 #include <linux/hrtimer.h> 147 #include <linux/netfilter_netdev.h> 148 #include <linux/crash_dump.h> 149 #include <linux/sctp.h> 150 #include <net/udp_tunnel.h> 151 #include <linux/net_namespace.h> 152 #include <linux/indirect_call_wrapper.h> 153 #include <net/devlink.h> 154 #include <linux/pm_runtime.h> 155 #include <linux/prandom.h> 156 #include <linux/once_lite.h> 157 #include <net/netdev_rx_queue.h> 158 #include <net/page_pool/types.h> 159 #include <net/page_pool/helpers.h> 160 #include <net/rps.h> 161 #include <linux/phy_link_topology_core.h> 162 163 #include "dev.h" 164 #include "net-sysfs.h" 165 166 static DEFINE_SPINLOCK(ptype_lock); 167 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 168 169 static int netif_rx_internal(struct sk_buff *skb); 170 static int call_netdevice_notifiers_extack(unsigned long val, 171 struct net_device *dev, 172 struct netlink_ext_ack *extack); 173 174 static DEFINE_MUTEX(ifalias_mutex); 175 176 /* protects napi_hash addition/deletion and napi_gen_id */ 177 static DEFINE_SPINLOCK(napi_hash_lock); 178 179 static unsigned int napi_gen_id = NR_CPUS; 180 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 181 182 static DECLARE_RWSEM(devnet_rename_sem); 183 184 static inline void dev_base_seq_inc(struct net *net) 185 { 186 unsigned int val = net->dev_base_seq + 1; 187 188 WRITE_ONCE(net->dev_base_seq, val ?: 1); 189 } 190 191 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 192 { 193 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 194 195 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 196 } 197 198 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 199 { 200 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 201 } 202 203 #ifndef CONFIG_PREEMPT_RT 204 205 static DEFINE_STATIC_KEY_FALSE(use_backlog_threads_key); 206 207 static int __init setup_backlog_napi_threads(char *arg) 208 { 209 static_branch_enable(&use_backlog_threads_key); 210 return 0; 211 } 212 early_param("thread_backlog_napi", setup_backlog_napi_threads); 213 214 static bool use_backlog_threads(void) 215 { 216 return static_branch_unlikely(&use_backlog_threads_key); 217 } 218 219 #else 220 221 static bool use_backlog_threads(void) 222 { 223 return true; 224 } 225 226 #endif 227 228 static inline void backlog_lock_irq_save(struct softnet_data *sd, 229 unsigned long *flags) 230 { 231 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 232 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 233 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 234 local_irq_save(*flags); 235 } 236 237 static inline void backlog_lock_irq_disable(struct softnet_data *sd) 238 { 239 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 240 spin_lock_irq(&sd->input_pkt_queue.lock); 241 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 242 local_irq_disable(); 243 } 244 245 static inline void backlog_unlock_irq_restore(struct softnet_data *sd, 246 unsigned long *flags) 247 { 248 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 249 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 250 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 251 local_irq_restore(*flags); 252 } 253 254 static inline void backlog_unlock_irq_enable(struct softnet_data *sd) 255 { 256 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 257 spin_unlock_irq(&sd->input_pkt_queue.lock); 258 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 259 local_irq_enable(); 260 } 261 262 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 263 const char *name) 264 { 265 struct netdev_name_node *name_node; 266 267 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 268 if (!name_node) 269 return NULL; 270 INIT_HLIST_NODE(&name_node->hlist); 271 name_node->dev = dev; 272 name_node->name = name; 273 return name_node; 274 } 275 276 static struct netdev_name_node * 277 netdev_name_node_head_alloc(struct net_device *dev) 278 { 279 struct netdev_name_node *name_node; 280 281 name_node = netdev_name_node_alloc(dev, dev->name); 282 if (!name_node) 283 return NULL; 284 INIT_LIST_HEAD(&name_node->list); 285 return name_node; 286 } 287 288 static void netdev_name_node_free(struct netdev_name_node *name_node) 289 { 290 kfree(name_node); 291 } 292 293 static void netdev_name_node_add(struct net *net, 294 struct netdev_name_node *name_node) 295 { 296 hlist_add_head_rcu(&name_node->hlist, 297 dev_name_hash(net, name_node->name)); 298 } 299 300 static void netdev_name_node_del(struct netdev_name_node *name_node) 301 { 302 hlist_del_rcu(&name_node->hlist); 303 } 304 305 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 306 const char *name) 307 { 308 struct hlist_head *head = dev_name_hash(net, name); 309 struct netdev_name_node *name_node; 310 311 hlist_for_each_entry(name_node, head, hlist) 312 if (!strcmp(name_node->name, name)) 313 return name_node; 314 return NULL; 315 } 316 317 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 318 const char *name) 319 { 320 struct hlist_head *head = dev_name_hash(net, name); 321 struct netdev_name_node *name_node; 322 323 hlist_for_each_entry_rcu(name_node, head, hlist) 324 if (!strcmp(name_node->name, name)) 325 return name_node; 326 return NULL; 327 } 328 329 bool netdev_name_in_use(struct net *net, const char *name) 330 { 331 return netdev_name_node_lookup(net, name); 332 } 333 EXPORT_SYMBOL(netdev_name_in_use); 334 335 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 336 { 337 struct netdev_name_node *name_node; 338 struct net *net = dev_net(dev); 339 340 name_node = netdev_name_node_lookup(net, name); 341 if (name_node) 342 return -EEXIST; 343 name_node = netdev_name_node_alloc(dev, name); 344 if (!name_node) 345 return -ENOMEM; 346 netdev_name_node_add(net, name_node); 347 /* The node that holds dev->name acts as a head of per-device list. */ 348 list_add_tail_rcu(&name_node->list, &dev->name_node->list); 349 350 return 0; 351 } 352 353 static void netdev_name_node_alt_free(struct rcu_head *head) 354 { 355 struct netdev_name_node *name_node = 356 container_of(head, struct netdev_name_node, rcu); 357 358 kfree(name_node->name); 359 netdev_name_node_free(name_node); 360 } 361 362 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 363 { 364 netdev_name_node_del(name_node); 365 list_del(&name_node->list); 366 call_rcu(&name_node->rcu, netdev_name_node_alt_free); 367 } 368 369 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 370 { 371 struct netdev_name_node *name_node; 372 struct net *net = dev_net(dev); 373 374 name_node = netdev_name_node_lookup(net, name); 375 if (!name_node) 376 return -ENOENT; 377 /* lookup might have found our primary name or a name belonging 378 * to another device. 379 */ 380 if (name_node == dev->name_node || name_node->dev != dev) 381 return -EINVAL; 382 383 __netdev_name_node_alt_destroy(name_node); 384 return 0; 385 } 386 387 static void netdev_name_node_alt_flush(struct net_device *dev) 388 { 389 struct netdev_name_node *name_node, *tmp; 390 391 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) { 392 list_del(&name_node->list); 393 netdev_name_node_alt_free(&name_node->rcu); 394 } 395 } 396 397 /* Device list insertion */ 398 static void list_netdevice(struct net_device *dev) 399 { 400 struct netdev_name_node *name_node; 401 struct net *net = dev_net(dev); 402 403 ASSERT_RTNL(); 404 405 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 406 netdev_name_node_add(net, dev->name_node); 407 hlist_add_head_rcu(&dev->index_hlist, 408 dev_index_hash(net, dev->ifindex)); 409 410 netdev_for_each_altname(dev, name_node) 411 netdev_name_node_add(net, name_node); 412 413 /* We reserved the ifindex, this can't fail */ 414 WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL)); 415 416 dev_base_seq_inc(net); 417 } 418 419 /* Device list removal 420 * caller must respect a RCU grace period before freeing/reusing dev 421 */ 422 static void unlist_netdevice(struct net_device *dev) 423 { 424 struct netdev_name_node *name_node; 425 struct net *net = dev_net(dev); 426 427 ASSERT_RTNL(); 428 429 xa_erase(&net->dev_by_index, dev->ifindex); 430 431 netdev_for_each_altname(dev, name_node) 432 netdev_name_node_del(name_node); 433 434 /* Unlink dev from the device chain */ 435 list_del_rcu(&dev->dev_list); 436 netdev_name_node_del(dev->name_node); 437 hlist_del_rcu(&dev->index_hlist); 438 439 dev_base_seq_inc(dev_net(dev)); 440 } 441 442 /* 443 * Our notifier list 444 */ 445 446 static RAW_NOTIFIER_HEAD(netdev_chain); 447 448 /* 449 * Device drivers call our routines to queue packets here. We empty the 450 * queue in the local softnet handler. 451 */ 452 453 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 454 EXPORT_PER_CPU_SYMBOL(softnet_data); 455 456 /* Page_pool has a lockless array/stack to alloc/recycle pages. 457 * PP consumers must pay attention to run APIs in the appropriate context 458 * (e.g. NAPI context). 459 */ 460 static DEFINE_PER_CPU(struct page_pool *, system_page_pool); 461 462 #ifdef CONFIG_LOCKDEP 463 /* 464 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 465 * according to dev->type 466 */ 467 static const unsigned short netdev_lock_type[] = { 468 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 469 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 470 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 471 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 472 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 473 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 474 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 475 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 476 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 477 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 478 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 479 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 480 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 481 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 482 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 483 484 static const char *const netdev_lock_name[] = { 485 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 486 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 487 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 488 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 489 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 490 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 491 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 492 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 493 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 494 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 495 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 496 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 497 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 498 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 499 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 500 501 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 502 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 503 504 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 505 { 506 int i; 507 508 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 509 if (netdev_lock_type[i] == dev_type) 510 return i; 511 /* the last key is used by default */ 512 return ARRAY_SIZE(netdev_lock_type) - 1; 513 } 514 515 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 516 unsigned short dev_type) 517 { 518 int i; 519 520 i = netdev_lock_pos(dev_type); 521 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 522 netdev_lock_name[i]); 523 } 524 525 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 526 { 527 int i; 528 529 i = netdev_lock_pos(dev->type); 530 lockdep_set_class_and_name(&dev->addr_list_lock, 531 &netdev_addr_lock_key[i], 532 netdev_lock_name[i]); 533 } 534 #else 535 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 536 unsigned short dev_type) 537 { 538 } 539 540 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 541 { 542 } 543 #endif 544 545 /******************************************************************************* 546 * 547 * Protocol management and registration routines 548 * 549 *******************************************************************************/ 550 551 552 /* 553 * Add a protocol ID to the list. Now that the input handler is 554 * smarter we can dispense with all the messy stuff that used to be 555 * here. 556 * 557 * BEWARE!!! Protocol handlers, mangling input packets, 558 * MUST BE last in hash buckets and checking protocol handlers 559 * MUST start from promiscuous ptype_all chain in net_bh. 560 * It is true now, do not change it. 561 * Explanation follows: if protocol handler, mangling packet, will 562 * be the first on list, it is not able to sense, that packet 563 * is cloned and should be copied-on-write, so that it will 564 * change it and subsequent readers will get broken packet. 565 * --ANK (980803) 566 */ 567 568 static inline struct list_head *ptype_head(const struct packet_type *pt) 569 { 570 if (pt->type == htons(ETH_P_ALL)) 571 return pt->dev ? &pt->dev->ptype_all : &net_hotdata.ptype_all; 572 else 573 return pt->dev ? &pt->dev->ptype_specific : 574 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 575 } 576 577 /** 578 * dev_add_pack - add packet handler 579 * @pt: packet type declaration 580 * 581 * Add a protocol handler to the networking stack. The passed &packet_type 582 * is linked into kernel lists and may not be freed until it has been 583 * removed from the kernel lists. 584 * 585 * This call does not sleep therefore it can not 586 * guarantee all CPU's that are in middle of receiving packets 587 * will see the new packet type (until the next received packet). 588 */ 589 590 void dev_add_pack(struct packet_type *pt) 591 { 592 struct list_head *head = ptype_head(pt); 593 594 spin_lock(&ptype_lock); 595 list_add_rcu(&pt->list, head); 596 spin_unlock(&ptype_lock); 597 } 598 EXPORT_SYMBOL(dev_add_pack); 599 600 /** 601 * __dev_remove_pack - remove packet handler 602 * @pt: packet type declaration 603 * 604 * Remove a protocol handler that was previously added to the kernel 605 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 606 * from the kernel lists and can be freed or reused once this function 607 * returns. 608 * 609 * The packet type might still be in use by receivers 610 * and must not be freed until after all the CPU's have gone 611 * through a quiescent state. 612 */ 613 void __dev_remove_pack(struct packet_type *pt) 614 { 615 struct list_head *head = ptype_head(pt); 616 struct packet_type *pt1; 617 618 spin_lock(&ptype_lock); 619 620 list_for_each_entry(pt1, head, list) { 621 if (pt == pt1) { 622 list_del_rcu(&pt->list); 623 goto out; 624 } 625 } 626 627 pr_warn("dev_remove_pack: %p not found\n", pt); 628 out: 629 spin_unlock(&ptype_lock); 630 } 631 EXPORT_SYMBOL(__dev_remove_pack); 632 633 /** 634 * dev_remove_pack - remove packet handler 635 * @pt: packet type declaration 636 * 637 * Remove a protocol handler that was previously added to the kernel 638 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 639 * from the kernel lists and can be freed or reused once this function 640 * returns. 641 * 642 * This call sleeps to guarantee that no CPU is looking at the packet 643 * type after return. 644 */ 645 void dev_remove_pack(struct packet_type *pt) 646 { 647 __dev_remove_pack(pt); 648 649 synchronize_net(); 650 } 651 EXPORT_SYMBOL(dev_remove_pack); 652 653 654 /******************************************************************************* 655 * 656 * Device Interface Subroutines 657 * 658 *******************************************************************************/ 659 660 /** 661 * dev_get_iflink - get 'iflink' value of a interface 662 * @dev: targeted interface 663 * 664 * Indicates the ifindex the interface is linked to. 665 * Physical interfaces have the same 'ifindex' and 'iflink' values. 666 */ 667 668 int dev_get_iflink(const struct net_device *dev) 669 { 670 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 671 return dev->netdev_ops->ndo_get_iflink(dev); 672 673 return READ_ONCE(dev->ifindex); 674 } 675 EXPORT_SYMBOL(dev_get_iflink); 676 677 /** 678 * dev_fill_metadata_dst - Retrieve tunnel egress information. 679 * @dev: targeted interface 680 * @skb: The packet. 681 * 682 * For better visibility of tunnel traffic OVS needs to retrieve 683 * egress tunnel information for a packet. Following API allows 684 * user to get this info. 685 */ 686 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 687 { 688 struct ip_tunnel_info *info; 689 690 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 691 return -EINVAL; 692 693 info = skb_tunnel_info_unclone(skb); 694 if (!info) 695 return -ENOMEM; 696 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 697 return -EINVAL; 698 699 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 700 } 701 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 702 703 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 704 { 705 int k = stack->num_paths++; 706 707 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 708 return NULL; 709 710 return &stack->path[k]; 711 } 712 713 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 714 struct net_device_path_stack *stack) 715 { 716 const struct net_device *last_dev; 717 struct net_device_path_ctx ctx = { 718 .dev = dev, 719 }; 720 struct net_device_path *path; 721 int ret = 0; 722 723 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 724 stack->num_paths = 0; 725 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 726 last_dev = ctx.dev; 727 path = dev_fwd_path(stack); 728 if (!path) 729 return -1; 730 731 memset(path, 0, sizeof(struct net_device_path)); 732 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 733 if (ret < 0) 734 return -1; 735 736 if (WARN_ON_ONCE(last_dev == ctx.dev)) 737 return -1; 738 } 739 740 if (!ctx.dev) 741 return ret; 742 743 path = dev_fwd_path(stack); 744 if (!path) 745 return -1; 746 path->type = DEV_PATH_ETHERNET; 747 path->dev = ctx.dev; 748 749 return ret; 750 } 751 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 752 753 /** 754 * __dev_get_by_name - find a device by its name 755 * @net: the applicable net namespace 756 * @name: name to find 757 * 758 * Find an interface by name. Must be called under RTNL semaphore. 759 * If the name is found a pointer to the device is returned. 760 * If the name is not found then %NULL is returned. The 761 * reference counters are not incremented so the caller must be 762 * careful with locks. 763 */ 764 765 struct net_device *__dev_get_by_name(struct net *net, const char *name) 766 { 767 struct netdev_name_node *node_name; 768 769 node_name = netdev_name_node_lookup(net, name); 770 return node_name ? node_name->dev : NULL; 771 } 772 EXPORT_SYMBOL(__dev_get_by_name); 773 774 /** 775 * dev_get_by_name_rcu - find a device by its name 776 * @net: the applicable net namespace 777 * @name: name to find 778 * 779 * Find an interface by name. 780 * If the name is found a pointer to the device is returned. 781 * If the name is not found then %NULL is returned. 782 * The reference counters are not incremented so the caller must be 783 * careful with locks. The caller must hold RCU lock. 784 */ 785 786 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 787 { 788 struct netdev_name_node *node_name; 789 790 node_name = netdev_name_node_lookup_rcu(net, name); 791 return node_name ? node_name->dev : NULL; 792 } 793 EXPORT_SYMBOL(dev_get_by_name_rcu); 794 795 /* Deprecated for new users, call netdev_get_by_name() instead */ 796 struct net_device *dev_get_by_name(struct net *net, const char *name) 797 { 798 struct net_device *dev; 799 800 rcu_read_lock(); 801 dev = dev_get_by_name_rcu(net, name); 802 dev_hold(dev); 803 rcu_read_unlock(); 804 return dev; 805 } 806 EXPORT_SYMBOL(dev_get_by_name); 807 808 /** 809 * netdev_get_by_name() - find a device by its name 810 * @net: the applicable net namespace 811 * @name: name to find 812 * @tracker: tracking object for the acquired reference 813 * @gfp: allocation flags for the tracker 814 * 815 * Find an interface by name. This can be called from any 816 * context and does its own locking. The returned handle has 817 * the usage count incremented and the caller must use netdev_put() to 818 * release it when it is no longer needed. %NULL is returned if no 819 * matching device is found. 820 */ 821 struct net_device *netdev_get_by_name(struct net *net, const char *name, 822 netdevice_tracker *tracker, gfp_t gfp) 823 { 824 struct net_device *dev; 825 826 dev = dev_get_by_name(net, name); 827 if (dev) 828 netdev_tracker_alloc(dev, tracker, gfp); 829 return dev; 830 } 831 EXPORT_SYMBOL(netdev_get_by_name); 832 833 /** 834 * __dev_get_by_index - find a device by its ifindex 835 * @net: the applicable net namespace 836 * @ifindex: index of device 837 * 838 * Search for an interface by index. Returns %NULL if the device 839 * is not found or a pointer to the device. The device has not 840 * had its reference counter increased so the caller must be careful 841 * about locking. The caller must hold the RTNL semaphore. 842 */ 843 844 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 845 { 846 struct net_device *dev; 847 struct hlist_head *head = dev_index_hash(net, ifindex); 848 849 hlist_for_each_entry(dev, head, index_hlist) 850 if (dev->ifindex == ifindex) 851 return dev; 852 853 return NULL; 854 } 855 EXPORT_SYMBOL(__dev_get_by_index); 856 857 /** 858 * dev_get_by_index_rcu - find a device by its ifindex 859 * @net: the applicable net namespace 860 * @ifindex: index of device 861 * 862 * Search for an interface by index. Returns %NULL if the device 863 * is not found or a pointer to the device. The device has not 864 * had its reference counter increased so the caller must be careful 865 * about locking. The caller must hold RCU lock. 866 */ 867 868 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 869 { 870 struct net_device *dev; 871 struct hlist_head *head = dev_index_hash(net, ifindex); 872 873 hlist_for_each_entry_rcu(dev, head, index_hlist) 874 if (dev->ifindex == ifindex) 875 return dev; 876 877 return NULL; 878 } 879 EXPORT_SYMBOL(dev_get_by_index_rcu); 880 881 /* Deprecated for new users, call netdev_get_by_index() instead */ 882 struct net_device *dev_get_by_index(struct net *net, int ifindex) 883 { 884 struct net_device *dev; 885 886 rcu_read_lock(); 887 dev = dev_get_by_index_rcu(net, ifindex); 888 dev_hold(dev); 889 rcu_read_unlock(); 890 return dev; 891 } 892 EXPORT_SYMBOL(dev_get_by_index); 893 894 /** 895 * netdev_get_by_index() - find a device by its ifindex 896 * @net: the applicable net namespace 897 * @ifindex: index of device 898 * @tracker: tracking object for the acquired reference 899 * @gfp: allocation flags for the tracker 900 * 901 * Search for an interface by index. Returns NULL if the device 902 * is not found or a pointer to the device. The device returned has 903 * had a reference added and the pointer is safe until the user calls 904 * netdev_put() to indicate they have finished with it. 905 */ 906 struct net_device *netdev_get_by_index(struct net *net, int ifindex, 907 netdevice_tracker *tracker, gfp_t gfp) 908 { 909 struct net_device *dev; 910 911 dev = dev_get_by_index(net, ifindex); 912 if (dev) 913 netdev_tracker_alloc(dev, tracker, gfp); 914 return dev; 915 } 916 EXPORT_SYMBOL(netdev_get_by_index); 917 918 /** 919 * dev_get_by_napi_id - find a device by napi_id 920 * @napi_id: ID of the NAPI struct 921 * 922 * Search for an interface by NAPI ID. Returns %NULL if the device 923 * is not found or a pointer to the device. The device has not had 924 * its reference counter increased so the caller must be careful 925 * about locking. The caller must hold RCU lock. 926 */ 927 928 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 929 { 930 struct napi_struct *napi; 931 932 WARN_ON_ONCE(!rcu_read_lock_held()); 933 934 if (napi_id < MIN_NAPI_ID) 935 return NULL; 936 937 napi = napi_by_id(napi_id); 938 939 return napi ? napi->dev : NULL; 940 } 941 EXPORT_SYMBOL(dev_get_by_napi_id); 942 943 static DEFINE_SEQLOCK(netdev_rename_lock); 944 945 void netdev_copy_name(struct net_device *dev, char *name) 946 { 947 unsigned int seq; 948 949 do { 950 seq = read_seqbegin(&netdev_rename_lock); 951 strscpy(name, dev->name, IFNAMSIZ); 952 } while (read_seqretry(&netdev_rename_lock, seq)); 953 } 954 955 /** 956 * netdev_get_name - get a netdevice name, knowing its ifindex. 957 * @net: network namespace 958 * @name: a pointer to the buffer where the name will be stored. 959 * @ifindex: the ifindex of the interface to get the name from. 960 */ 961 int netdev_get_name(struct net *net, char *name, int ifindex) 962 { 963 struct net_device *dev; 964 int ret; 965 966 rcu_read_lock(); 967 968 dev = dev_get_by_index_rcu(net, ifindex); 969 if (!dev) { 970 ret = -ENODEV; 971 goto out; 972 } 973 974 netdev_copy_name(dev, name); 975 976 ret = 0; 977 out: 978 rcu_read_unlock(); 979 return ret; 980 } 981 982 /** 983 * dev_getbyhwaddr_rcu - find a device by its hardware address 984 * @net: the applicable net namespace 985 * @type: media type of device 986 * @ha: hardware address 987 * 988 * Search for an interface by MAC address. Returns NULL if the device 989 * is not found or a pointer to the device. 990 * The caller must hold RCU or RTNL. 991 * The returned device has not had its ref count increased 992 * and the caller must therefore be careful about locking 993 * 994 */ 995 996 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 997 const char *ha) 998 { 999 struct net_device *dev; 1000 1001 for_each_netdev_rcu(net, dev) 1002 if (dev->type == type && 1003 !memcmp(dev->dev_addr, ha, dev->addr_len)) 1004 return dev; 1005 1006 return NULL; 1007 } 1008 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 1009 1010 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 1011 { 1012 struct net_device *dev, *ret = NULL; 1013 1014 rcu_read_lock(); 1015 for_each_netdev_rcu(net, dev) 1016 if (dev->type == type) { 1017 dev_hold(dev); 1018 ret = dev; 1019 break; 1020 } 1021 rcu_read_unlock(); 1022 return ret; 1023 } 1024 EXPORT_SYMBOL(dev_getfirstbyhwtype); 1025 1026 /** 1027 * __dev_get_by_flags - find any device with given flags 1028 * @net: the applicable net namespace 1029 * @if_flags: IFF_* values 1030 * @mask: bitmask of bits in if_flags to check 1031 * 1032 * Search for any interface with the given flags. Returns NULL if a device 1033 * is not found or a pointer to the device. Must be called inside 1034 * rtnl_lock(), and result refcount is unchanged. 1035 */ 1036 1037 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 1038 unsigned short mask) 1039 { 1040 struct net_device *dev, *ret; 1041 1042 ASSERT_RTNL(); 1043 1044 ret = NULL; 1045 for_each_netdev(net, dev) { 1046 if (((dev->flags ^ if_flags) & mask) == 0) { 1047 ret = dev; 1048 break; 1049 } 1050 } 1051 return ret; 1052 } 1053 EXPORT_SYMBOL(__dev_get_by_flags); 1054 1055 /** 1056 * dev_valid_name - check if name is okay for network device 1057 * @name: name string 1058 * 1059 * Network device names need to be valid file names to 1060 * allow sysfs to work. We also disallow any kind of 1061 * whitespace. 1062 */ 1063 bool dev_valid_name(const char *name) 1064 { 1065 if (*name == '\0') 1066 return false; 1067 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1068 return false; 1069 if (!strcmp(name, ".") || !strcmp(name, "..")) 1070 return false; 1071 1072 while (*name) { 1073 if (*name == '/' || *name == ':' || isspace(*name)) 1074 return false; 1075 name++; 1076 } 1077 return true; 1078 } 1079 EXPORT_SYMBOL(dev_valid_name); 1080 1081 /** 1082 * __dev_alloc_name - allocate a name for a device 1083 * @net: network namespace to allocate the device name in 1084 * @name: name format string 1085 * @res: result name string 1086 * 1087 * Passed a format string - eg "lt%d" it will try and find a suitable 1088 * id. It scans list of devices to build up a free map, then chooses 1089 * the first empty slot. The caller must hold the dev_base or rtnl lock 1090 * while allocating the name and adding the device in order to avoid 1091 * duplicates. 1092 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1093 * Returns the number of the unit assigned or a negative errno code. 1094 */ 1095 1096 static int __dev_alloc_name(struct net *net, const char *name, char *res) 1097 { 1098 int i = 0; 1099 const char *p; 1100 const int max_netdevices = 8*PAGE_SIZE; 1101 unsigned long *inuse; 1102 struct net_device *d; 1103 char buf[IFNAMSIZ]; 1104 1105 /* Verify the string as this thing may have come from the user. 1106 * There must be one "%d" and no other "%" characters. 1107 */ 1108 p = strchr(name, '%'); 1109 if (!p || p[1] != 'd' || strchr(p + 2, '%')) 1110 return -EINVAL; 1111 1112 /* Use one page as a bit array of possible slots */ 1113 inuse = bitmap_zalloc(max_netdevices, GFP_ATOMIC); 1114 if (!inuse) 1115 return -ENOMEM; 1116 1117 for_each_netdev(net, d) { 1118 struct netdev_name_node *name_node; 1119 1120 netdev_for_each_altname(d, name_node) { 1121 if (!sscanf(name_node->name, name, &i)) 1122 continue; 1123 if (i < 0 || i >= max_netdevices) 1124 continue; 1125 1126 /* avoid cases where sscanf is not exact inverse of printf */ 1127 snprintf(buf, IFNAMSIZ, name, i); 1128 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1129 __set_bit(i, inuse); 1130 } 1131 if (!sscanf(d->name, name, &i)) 1132 continue; 1133 if (i < 0 || i >= max_netdevices) 1134 continue; 1135 1136 /* avoid cases where sscanf is not exact inverse of printf */ 1137 snprintf(buf, IFNAMSIZ, name, i); 1138 if (!strncmp(buf, d->name, IFNAMSIZ)) 1139 __set_bit(i, inuse); 1140 } 1141 1142 i = find_first_zero_bit(inuse, max_netdevices); 1143 bitmap_free(inuse); 1144 if (i == max_netdevices) 1145 return -ENFILE; 1146 1147 /* 'res' and 'name' could overlap, use 'buf' as an intermediate buffer */ 1148 strscpy(buf, name, IFNAMSIZ); 1149 snprintf(res, IFNAMSIZ, buf, i); 1150 return i; 1151 } 1152 1153 /* Returns negative errno or allocated unit id (see __dev_alloc_name()) */ 1154 static int dev_prep_valid_name(struct net *net, struct net_device *dev, 1155 const char *want_name, char *out_name, 1156 int dup_errno) 1157 { 1158 if (!dev_valid_name(want_name)) 1159 return -EINVAL; 1160 1161 if (strchr(want_name, '%')) 1162 return __dev_alloc_name(net, want_name, out_name); 1163 1164 if (netdev_name_in_use(net, want_name)) 1165 return -dup_errno; 1166 if (out_name != want_name) 1167 strscpy(out_name, want_name, IFNAMSIZ); 1168 return 0; 1169 } 1170 1171 /** 1172 * dev_alloc_name - allocate a name for a device 1173 * @dev: device 1174 * @name: name format string 1175 * 1176 * Passed a format string - eg "lt%d" it will try and find a suitable 1177 * id. It scans list of devices to build up a free map, then chooses 1178 * the first empty slot. The caller must hold the dev_base or rtnl lock 1179 * while allocating the name and adding the device in order to avoid 1180 * duplicates. 1181 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1182 * Returns the number of the unit assigned or a negative errno code. 1183 */ 1184 1185 int dev_alloc_name(struct net_device *dev, const char *name) 1186 { 1187 return dev_prep_valid_name(dev_net(dev), dev, name, dev->name, ENFILE); 1188 } 1189 EXPORT_SYMBOL(dev_alloc_name); 1190 1191 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1192 const char *name) 1193 { 1194 int ret; 1195 1196 ret = dev_prep_valid_name(net, dev, name, dev->name, EEXIST); 1197 return ret < 0 ? ret : 0; 1198 } 1199 1200 /** 1201 * dev_change_name - change name of a device 1202 * @dev: device 1203 * @newname: name (or format string) must be at least IFNAMSIZ 1204 * 1205 * Change name of a device, can pass format strings "eth%d". 1206 * for wildcarding. 1207 */ 1208 int dev_change_name(struct net_device *dev, const char *newname) 1209 { 1210 unsigned char old_assign_type; 1211 char oldname[IFNAMSIZ]; 1212 int err = 0; 1213 int ret; 1214 struct net *net; 1215 1216 ASSERT_RTNL(); 1217 BUG_ON(!dev_net(dev)); 1218 1219 net = dev_net(dev); 1220 1221 down_write(&devnet_rename_sem); 1222 1223 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1224 up_write(&devnet_rename_sem); 1225 return 0; 1226 } 1227 1228 memcpy(oldname, dev->name, IFNAMSIZ); 1229 1230 write_seqlock(&netdev_rename_lock); 1231 err = dev_get_valid_name(net, dev, newname); 1232 write_sequnlock(&netdev_rename_lock); 1233 1234 if (err < 0) { 1235 up_write(&devnet_rename_sem); 1236 return err; 1237 } 1238 1239 if (oldname[0] && !strchr(oldname, '%')) 1240 netdev_info(dev, "renamed from %s%s\n", oldname, 1241 dev->flags & IFF_UP ? " (while UP)" : ""); 1242 1243 old_assign_type = dev->name_assign_type; 1244 WRITE_ONCE(dev->name_assign_type, NET_NAME_RENAMED); 1245 1246 rollback: 1247 ret = device_rename(&dev->dev, dev->name); 1248 if (ret) { 1249 memcpy(dev->name, oldname, IFNAMSIZ); 1250 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1251 up_write(&devnet_rename_sem); 1252 return ret; 1253 } 1254 1255 up_write(&devnet_rename_sem); 1256 1257 netdev_adjacent_rename_links(dev, oldname); 1258 1259 netdev_name_node_del(dev->name_node); 1260 1261 synchronize_net(); 1262 1263 netdev_name_node_add(net, dev->name_node); 1264 1265 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1266 ret = notifier_to_errno(ret); 1267 1268 if (ret) { 1269 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1270 if (err >= 0) { 1271 err = ret; 1272 down_write(&devnet_rename_sem); 1273 write_seqlock(&netdev_rename_lock); 1274 memcpy(dev->name, oldname, IFNAMSIZ); 1275 write_sequnlock(&netdev_rename_lock); 1276 memcpy(oldname, newname, IFNAMSIZ); 1277 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1278 old_assign_type = NET_NAME_RENAMED; 1279 goto rollback; 1280 } else { 1281 netdev_err(dev, "name change rollback failed: %d\n", 1282 ret); 1283 } 1284 } 1285 1286 return err; 1287 } 1288 1289 /** 1290 * dev_set_alias - change ifalias of a device 1291 * @dev: device 1292 * @alias: name up to IFALIASZ 1293 * @len: limit of bytes to copy from info 1294 * 1295 * Set ifalias for a device, 1296 */ 1297 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1298 { 1299 struct dev_ifalias *new_alias = NULL; 1300 1301 if (len >= IFALIASZ) 1302 return -EINVAL; 1303 1304 if (len) { 1305 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1306 if (!new_alias) 1307 return -ENOMEM; 1308 1309 memcpy(new_alias->ifalias, alias, len); 1310 new_alias->ifalias[len] = 0; 1311 } 1312 1313 mutex_lock(&ifalias_mutex); 1314 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1315 mutex_is_locked(&ifalias_mutex)); 1316 mutex_unlock(&ifalias_mutex); 1317 1318 if (new_alias) 1319 kfree_rcu(new_alias, rcuhead); 1320 1321 return len; 1322 } 1323 EXPORT_SYMBOL(dev_set_alias); 1324 1325 /** 1326 * dev_get_alias - get ifalias of a device 1327 * @dev: device 1328 * @name: buffer to store name of ifalias 1329 * @len: size of buffer 1330 * 1331 * get ifalias for a device. Caller must make sure dev cannot go 1332 * away, e.g. rcu read lock or own a reference count to device. 1333 */ 1334 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1335 { 1336 const struct dev_ifalias *alias; 1337 int ret = 0; 1338 1339 rcu_read_lock(); 1340 alias = rcu_dereference(dev->ifalias); 1341 if (alias) 1342 ret = snprintf(name, len, "%s", alias->ifalias); 1343 rcu_read_unlock(); 1344 1345 return ret; 1346 } 1347 1348 /** 1349 * netdev_features_change - device changes features 1350 * @dev: device to cause notification 1351 * 1352 * Called to indicate a device has changed features. 1353 */ 1354 void netdev_features_change(struct net_device *dev) 1355 { 1356 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1357 } 1358 EXPORT_SYMBOL(netdev_features_change); 1359 1360 /** 1361 * netdev_state_change - device changes state 1362 * @dev: device to cause notification 1363 * 1364 * Called to indicate a device has changed state. This function calls 1365 * the notifier chains for netdev_chain and sends a NEWLINK message 1366 * to the routing socket. 1367 */ 1368 void netdev_state_change(struct net_device *dev) 1369 { 1370 if (dev->flags & IFF_UP) { 1371 struct netdev_notifier_change_info change_info = { 1372 .info.dev = dev, 1373 }; 1374 1375 call_netdevice_notifiers_info(NETDEV_CHANGE, 1376 &change_info.info); 1377 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1378 } 1379 } 1380 EXPORT_SYMBOL(netdev_state_change); 1381 1382 /** 1383 * __netdev_notify_peers - notify network peers about existence of @dev, 1384 * to be called when rtnl lock is already held. 1385 * @dev: network device 1386 * 1387 * Generate traffic such that interested network peers are aware of 1388 * @dev, such as by generating a gratuitous ARP. This may be used when 1389 * a device wants to inform the rest of the network about some sort of 1390 * reconfiguration such as a failover event or virtual machine 1391 * migration. 1392 */ 1393 void __netdev_notify_peers(struct net_device *dev) 1394 { 1395 ASSERT_RTNL(); 1396 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1397 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1398 } 1399 EXPORT_SYMBOL(__netdev_notify_peers); 1400 1401 /** 1402 * netdev_notify_peers - notify network peers about existence of @dev 1403 * @dev: network device 1404 * 1405 * Generate traffic such that interested network peers are aware of 1406 * @dev, such as by generating a gratuitous ARP. This may be used when 1407 * a device wants to inform the rest of the network about some sort of 1408 * reconfiguration such as a failover event or virtual machine 1409 * migration. 1410 */ 1411 void netdev_notify_peers(struct net_device *dev) 1412 { 1413 rtnl_lock(); 1414 __netdev_notify_peers(dev); 1415 rtnl_unlock(); 1416 } 1417 EXPORT_SYMBOL(netdev_notify_peers); 1418 1419 static int napi_threaded_poll(void *data); 1420 1421 static int napi_kthread_create(struct napi_struct *n) 1422 { 1423 int err = 0; 1424 1425 /* Create and wake up the kthread once to put it in 1426 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1427 * warning and work with loadavg. 1428 */ 1429 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1430 n->dev->name, n->napi_id); 1431 if (IS_ERR(n->thread)) { 1432 err = PTR_ERR(n->thread); 1433 pr_err("kthread_run failed with err %d\n", err); 1434 n->thread = NULL; 1435 } 1436 1437 return err; 1438 } 1439 1440 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1441 { 1442 const struct net_device_ops *ops = dev->netdev_ops; 1443 int ret; 1444 1445 ASSERT_RTNL(); 1446 dev_addr_check(dev); 1447 1448 if (!netif_device_present(dev)) { 1449 /* may be detached because parent is runtime-suspended */ 1450 if (dev->dev.parent) 1451 pm_runtime_resume(dev->dev.parent); 1452 if (!netif_device_present(dev)) 1453 return -ENODEV; 1454 } 1455 1456 /* Block netpoll from trying to do any rx path servicing. 1457 * If we don't do this there is a chance ndo_poll_controller 1458 * or ndo_poll may be running while we open the device 1459 */ 1460 netpoll_poll_disable(dev); 1461 1462 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1463 ret = notifier_to_errno(ret); 1464 if (ret) 1465 return ret; 1466 1467 set_bit(__LINK_STATE_START, &dev->state); 1468 1469 if (ops->ndo_validate_addr) 1470 ret = ops->ndo_validate_addr(dev); 1471 1472 if (!ret && ops->ndo_open) 1473 ret = ops->ndo_open(dev); 1474 1475 netpoll_poll_enable(dev); 1476 1477 if (ret) 1478 clear_bit(__LINK_STATE_START, &dev->state); 1479 else { 1480 dev->flags |= IFF_UP; 1481 dev_set_rx_mode(dev); 1482 dev_activate(dev); 1483 add_device_randomness(dev->dev_addr, dev->addr_len); 1484 } 1485 1486 return ret; 1487 } 1488 1489 /** 1490 * dev_open - prepare an interface for use. 1491 * @dev: device to open 1492 * @extack: netlink extended ack 1493 * 1494 * Takes a device from down to up state. The device's private open 1495 * function is invoked and then the multicast lists are loaded. Finally 1496 * the device is moved into the up state and a %NETDEV_UP message is 1497 * sent to the netdev notifier chain. 1498 * 1499 * Calling this function on an active interface is a nop. On a failure 1500 * a negative errno code is returned. 1501 */ 1502 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1503 { 1504 int ret; 1505 1506 if (dev->flags & IFF_UP) 1507 return 0; 1508 1509 ret = __dev_open(dev, extack); 1510 if (ret < 0) 1511 return ret; 1512 1513 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1514 call_netdevice_notifiers(NETDEV_UP, dev); 1515 1516 return ret; 1517 } 1518 EXPORT_SYMBOL(dev_open); 1519 1520 static void __dev_close_many(struct list_head *head) 1521 { 1522 struct net_device *dev; 1523 1524 ASSERT_RTNL(); 1525 might_sleep(); 1526 1527 list_for_each_entry(dev, head, close_list) { 1528 /* Temporarily disable netpoll until the interface is down */ 1529 netpoll_poll_disable(dev); 1530 1531 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1532 1533 clear_bit(__LINK_STATE_START, &dev->state); 1534 1535 /* Synchronize to scheduled poll. We cannot touch poll list, it 1536 * can be even on different cpu. So just clear netif_running(). 1537 * 1538 * dev->stop() will invoke napi_disable() on all of it's 1539 * napi_struct instances on this device. 1540 */ 1541 smp_mb__after_atomic(); /* Commit netif_running(). */ 1542 } 1543 1544 dev_deactivate_many(head); 1545 1546 list_for_each_entry(dev, head, close_list) { 1547 const struct net_device_ops *ops = dev->netdev_ops; 1548 1549 /* 1550 * Call the device specific close. This cannot fail. 1551 * Only if device is UP 1552 * 1553 * We allow it to be called even after a DETACH hot-plug 1554 * event. 1555 */ 1556 if (ops->ndo_stop) 1557 ops->ndo_stop(dev); 1558 1559 dev->flags &= ~IFF_UP; 1560 netpoll_poll_enable(dev); 1561 } 1562 } 1563 1564 static void __dev_close(struct net_device *dev) 1565 { 1566 LIST_HEAD(single); 1567 1568 list_add(&dev->close_list, &single); 1569 __dev_close_many(&single); 1570 list_del(&single); 1571 } 1572 1573 void dev_close_many(struct list_head *head, bool unlink) 1574 { 1575 struct net_device *dev, *tmp; 1576 1577 /* Remove the devices that don't need to be closed */ 1578 list_for_each_entry_safe(dev, tmp, head, close_list) 1579 if (!(dev->flags & IFF_UP)) 1580 list_del_init(&dev->close_list); 1581 1582 __dev_close_many(head); 1583 1584 list_for_each_entry_safe(dev, tmp, head, close_list) { 1585 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1586 call_netdevice_notifiers(NETDEV_DOWN, dev); 1587 if (unlink) 1588 list_del_init(&dev->close_list); 1589 } 1590 } 1591 EXPORT_SYMBOL(dev_close_many); 1592 1593 /** 1594 * dev_close - shutdown an interface. 1595 * @dev: device to shutdown 1596 * 1597 * This function moves an active device into down state. A 1598 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1599 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1600 * chain. 1601 */ 1602 void dev_close(struct net_device *dev) 1603 { 1604 if (dev->flags & IFF_UP) { 1605 LIST_HEAD(single); 1606 1607 list_add(&dev->close_list, &single); 1608 dev_close_many(&single, true); 1609 list_del(&single); 1610 } 1611 } 1612 EXPORT_SYMBOL(dev_close); 1613 1614 1615 /** 1616 * dev_disable_lro - disable Large Receive Offload on a device 1617 * @dev: device 1618 * 1619 * Disable Large Receive Offload (LRO) on a net device. Must be 1620 * called under RTNL. This is needed if received packets may be 1621 * forwarded to another interface. 1622 */ 1623 void dev_disable_lro(struct net_device *dev) 1624 { 1625 struct net_device *lower_dev; 1626 struct list_head *iter; 1627 1628 dev->wanted_features &= ~NETIF_F_LRO; 1629 netdev_update_features(dev); 1630 1631 if (unlikely(dev->features & NETIF_F_LRO)) 1632 netdev_WARN(dev, "failed to disable LRO!\n"); 1633 1634 netdev_for_each_lower_dev(dev, lower_dev, iter) 1635 dev_disable_lro(lower_dev); 1636 } 1637 EXPORT_SYMBOL(dev_disable_lro); 1638 1639 /** 1640 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1641 * @dev: device 1642 * 1643 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1644 * called under RTNL. This is needed if Generic XDP is installed on 1645 * the device. 1646 */ 1647 static void dev_disable_gro_hw(struct net_device *dev) 1648 { 1649 dev->wanted_features &= ~NETIF_F_GRO_HW; 1650 netdev_update_features(dev); 1651 1652 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1653 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1654 } 1655 1656 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1657 { 1658 #define N(val) \ 1659 case NETDEV_##val: \ 1660 return "NETDEV_" __stringify(val); 1661 switch (cmd) { 1662 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1663 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1664 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1665 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1666 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1667 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1668 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1669 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1670 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1671 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1672 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1673 N(XDP_FEAT_CHANGE) 1674 } 1675 #undef N 1676 return "UNKNOWN_NETDEV_EVENT"; 1677 } 1678 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1679 1680 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1681 struct net_device *dev) 1682 { 1683 struct netdev_notifier_info info = { 1684 .dev = dev, 1685 }; 1686 1687 return nb->notifier_call(nb, val, &info); 1688 } 1689 1690 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1691 struct net_device *dev) 1692 { 1693 int err; 1694 1695 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1696 err = notifier_to_errno(err); 1697 if (err) 1698 return err; 1699 1700 if (!(dev->flags & IFF_UP)) 1701 return 0; 1702 1703 call_netdevice_notifier(nb, NETDEV_UP, dev); 1704 return 0; 1705 } 1706 1707 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1708 struct net_device *dev) 1709 { 1710 if (dev->flags & IFF_UP) { 1711 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1712 dev); 1713 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1714 } 1715 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1716 } 1717 1718 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1719 struct net *net) 1720 { 1721 struct net_device *dev; 1722 int err; 1723 1724 for_each_netdev(net, dev) { 1725 err = call_netdevice_register_notifiers(nb, dev); 1726 if (err) 1727 goto rollback; 1728 } 1729 return 0; 1730 1731 rollback: 1732 for_each_netdev_continue_reverse(net, dev) 1733 call_netdevice_unregister_notifiers(nb, dev); 1734 return err; 1735 } 1736 1737 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1738 struct net *net) 1739 { 1740 struct net_device *dev; 1741 1742 for_each_netdev(net, dev) 1743 call_netdevice_unregister_notifiers(nb, dev); 1744 } 1745 1746 static int dev_boot_phase = 1; 1747 1748 /** 1749 * register_netdevice_notifier - register a network notifier block 1750 * @nb: notifier 1751 * 1752 * Register a notifier to be called when network device events occur. 1753 * The notifier passed is linked into the kernel structures and must 1754 * not be reused until it has been unregistered. A negative errno code 1755 * is returned on a failure. 1756 * 1757 * When registered all registration and up events are replayed 1758 * to the new notifier to allow device to have a race free 1759 * view of the network device list. 1760 */ 1761 1762 int register_netdevice_notifier(struct notifier_block *nb) 1763 { 1764 struct net *net; 1765 int err; 1766 1767 /* Close race with setup_net() and cleanup_net() */ 1768 down_write(&pernet_ops_rwsem); 1769 rtnl_lock(); 1770 err = raw_notifier_chain_register(&netdev_chain, nb); 1771 if (err) 1772 goto unlock; 1773 if (dev_boot_phase) 1774 goto unlock; 1775 for_each_net(net) { 1776 err = call_netdevice_register_net_notifiers(nb, net); 1777 if (err) 1778 goto rollback; 1779 } 1780 1781 unlock: 1782 rtnl_unlock(); 1783 up_write(&pernet_ops_rwsem); 1784 return err; 1785 1786 rollback: 1787 for_each_net_continue_reverse(net) 1788 call_netdevice_unregister_net_notifiers(nb, net); 1789 1790 raw_notifier_chain_unregister(&netdev_chain, nb); 1791 goto unlock; 1792 } 1793 EXPORT_SYMBOL(register_netdevice_notifier); 1794 1795 /** 1796 * unregister_netdevice_notifier - unregister a network notifier block 1797 * @nb: notifier 1798 * 1799 * Unregister a notifier previously registered by 1800 * register_netdevice_notifier(). The notifier is unlinked into the 1801 * kernel structures and may then be reused. A negative errno code 1802 * is returned on a failure. 1803 * 1804 * After unregistering unregister and down device events are synthesized 1805 * for all devices on the device list to the removed notifier to remove 1806 * the need for special case cleanup code. 1807 */ 1808 1809 int unregister_netdevice_notifier(struct notifier_block *nb) 1810 { 1811 struct net *net; 1812 int err; 1813 1814 /* Close race with setup_net() and cleanup_net() */ 1815 down_write(&pernet_ops_rwsem); 1816 rtnl_lock(); 1817 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1818 if (err) 1819 goto unlock; 1820 1821 for_each_net(net) 1822 call_netdevice_unregister_net_notifiers(nb, net); 1823 1824 unlock: 1825 rtnl_unlock(); 1826 up_write(&pernet_ops_rwsem); 1827 return err; 1828 } 1829 EXPORT_SYMBOL(unregister_netdevice_notifier); 1830 1831 static int __register_netdevice_notifier_net(struct net *net, 1832 struct notifier_block *nb, 1833 bool ignore_call_fail) 1834 { 1835 int err; 1836 1837 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1838 if (err) 1839 return err; 1840 if (dev_boot_phase) 1841 return 0; 1842 1843 err = call_netdevice_register_net_notifiers(nb, net); 1844 if (err && !ignore_call_fail) 1845 goto chain_unregister; 1846 1847 return 0; 1848 1849 chain_unregister: 1850 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1851 return err; 1852 } 1853 1854 static int __unregister_netdevice_notifier_net(struct net *net, 1855 struct notifier_block *nb) 1856 { 1857 int err; 1858 1859 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1860 if (err) 1861 return err; 1862 1863 call_netdevice_unregister_net_notifiers(nb, net); 1864 return 0; 1865 } 1866 1867 /** 1868 * register_netdevice_notifier_net - register a per-netns network notifier block 1869 * @net: network namespace 1870 * @nb: notifier 1871 * 1872 * Register a notifier to be called when network device events occur. 1873 * The notifier passed is linked into the kernel structures and must 1874 * not be reused until it has been unregistered. A negative errno code 1875 * is returned on a failure. 1876 * 1877 * When registered all registration and up events are replayed 1878 * to the new notifier to allow device to have a race free 1879 * view of the network device list. 1880 */ 1881 1882 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1883 { 1884 int err; 1885 1886 rtnl_lock(); 1887 err = __register_netdevice_notifier_net(net, nb, false); 1888 rtnl_unlock(); 1889 return err; 1890 } 1891 EXPORT_SYMBOL(register_netdevice_notifier_net); 1892 1893 /** 1894 * unregister_netdevice_notifier_net - unregister a per-netns 1895 * network notifier block 1896 * @net: network namespace 1897 * @nb: notifier 1898 * 1899 * Unregister a notifier previously registered by 1900 * register_netdevice_notifier_net(). The notifier is unlinked from the 1901 * kernel structures and may then be reused. A negative errno code 1902 * is returned on a failure. 1903 * 1904 * After unregistering unregister and down device events are synthesized 1905 * for all devices on the device list to the removed notifier to remove 1906 * the need for special case cleanup code. 1907 */ 1908 1909 int unregister_netdevice_notifier_net(struct net *net, 1910 struct notifier_block *nb) 1911 { 1912 int err; 1913 1914 rtnl_lock(); 1915 err = __unregister_netdevice_notifier_net(net, nb); 1916 rtnl_unlock(); 1917 return err; 1918 } 1919 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1920 1921 static void __move_netdevice_notifier_net(struct net *src_net, 1922 struct net *dst_net, 1923 struct notifier_block *nb) 1924 { 1925 __unregister_netdevice_notifier_net(src_net, nb); 1926 __register_netdevice_notifier_net(dst_net, nb, true); 1927 } 1928 1929 int register_netdevice_notifier_dev_net(struct net_device *dev, 1930 struct notifier_block *nb, 1931 struct netdev_net_notifier *nn) 1932 { 1933 int err; 1934 1935 rtnl_lock(); 1936 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1937 if (!err) { 1938 nn->nb = nb; 1939 list_add(&nn->list, &dev->net_notifier_list); 1940 } 1941 rtnl_unlock(); 1942 return err; 1943 } 1944 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1945 1946 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1947 struct notifier_block *nb, 1948 struct netdev_net_notifier *nn) 1949 { 1950 int err; 1951 1952 rtnl_lock(); 1953 list_del(&nn->list); 1954 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1955 rtnl_unlock(); 1956 return err; 1957 } 1958 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1959 1960 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1961 struct net *net) 1962 { 1963 struct netdev_net_notifier *nn; 1964 1965 list_for_each_entry(nn, &dev->net_notifier_list, list) 1966 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 1967 } 1968 1969 /** 1970 * call_netdevice_notifiers_info - call all network notifier blocks 1971 * @val: value passed unmodified to notifier function 1972 * @info: notifier information data 1973 * 1974 * Call all network notifier blocks. Parameters and return value 1975 * are as for raw_notifier_call_chain(). 1976 */ 1977 1978 int call_netdevice_notifiers_info(unsigned long val, 1979 struct netdev_notifier_info *info) 1980 { 1981 struct net *net = dev_net(info->dev); 1982 int ret; 1983 1984 ASSERT_RTNL(); 1985 1986 /* Run per-netns notifier block chain first, then run the global one. 1987 * Hopefully, one day, the global one is going to be removed after 1988 * all notifier block registrators get converted to be per-netns. 1989 */ 1990 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1991 if (ret & NOTIFY_STOP_MASK) 1992 return ret; 1993 return raw_notifier_call_chain(&netdev_chain, val, info); 1994 } 1995 1996 /** 1997 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 1998 * for and rollback on error 1999 * @val_up: value passed unmodified to notifier function 2000 * @val_down: value passed unmodified to the notifier function when 2001 * recovering from an error on @val_up 2002 * @info: notifier information data 2003 * 2004 * Call all per-netns network notifier blocks, but not notifier blocks on 2005 * the global notifier chain. Parameters and return value are as for 2006 * raw_notifier_call_chain_robust(). 2007 */ 2008 2009 static int 2010 call_netdevice_notifiers_info_robust(unsigned long val_up, 2011 unsigned long val_down, 2012 struct netdev_notifier_info *info) 2013 { 2014 struct net *net = dev_net(info->dev); 2015 2016 ASSERT_RTNL(); 2017 2018 return raw_notifier_call_chain_robust(&net->netdev_chain, 2019 val_up, val_down, info); 2020 } 2021 2022 static int call_netdevice_notifiers_extack(unsigned long val, 2023 struct net_device *dev, 2024 struct netlink_ext_ack *extack) 2025 { 2026 struct netdev_notifier_info info = { 2027 .dev = dev, 2028 .extack = extack, 2029 }; 2030 2031 return call_netdevice_notifiers_info(val, &info); 2032 } 2033 2034 /** 2035 * call_netdevice_notifiers - call all network notifier blocks 2036 * @val: value passed unmodified to notifier function 2037 * @dev: net_device pointer passed unmodified to notifier function 2038 * 2039 * Call all network notifier blocks. Parameters and return value 2040 * are as for raw_notifier_call_chain(). 2041 */ 2042 2043 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 2044 { 2045 return call_netdevice_notifiers_extack(val, dev, NULL); 2046 } 2047 EXPORT_SYMBOL(call_netdevice_notifiers); 2048 2049 /** 2050 * call_netdevice_notifiers_mtu - call all network notifier blocks 2051 * @val: value passed unmodified to notifier function 2052 * @dev: net_device pointer passed unmodified to notifier function 2053 * @arg: additional u32 argument passed to the notifier function 2054 * 2055 * Call all network notifier blocks. Parameters and return value 2056 * are as for raw_notifier_call_chain(). 2057 */ 2058 static int call_netdevice_notifiers_mtu(unsigned long val, 2059 struct net_device *dev, u32 arg) 2060 { 2061 struct netdev_notifier_info_ext info = { 2062 .info.dev = dev, 2063 .ext.mtu = arg, 2064 }; 2065 2066 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2067 2068 return call_netdevice_notifiers_info(val, &info.info); 2069 } 2070 2071 #ifdef CONFIG_NET_INGRESS 2072 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2073 2074 void net_inc_ingress_queue(void) 2075 { 2076 static_branch_inc(&ingress_needed_key); 2077 } 2078 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2079 2080 void net_dec_ingress_queue(void) 2081 { 2082 static_branch_dec(&ingress_needed_key); 2083 } 2084 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2085 #endif 2086 2087 #ifdef CONFIG_NET_EGRESS 2088 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2089 2090 void net_inc_egress_queue(void) 2091 { 2092 static_branch_inc(&egress_needed_key); 2093 } 2094 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2095 2096 void net_dec_egress_queue(void) 2097 { 2098 static_branch_dec(&egress_needed_key); 2099 } 2100 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2101 #endif 2102 2103 #ifdef CONFIG_NET_CLS_ACT 2104 DEFINE_STATIC_KEY_FALSE(tcf_bypass_check_needed_key); 2105 EXPORT_SYMBOL(tcf_bypass_check_needed_key); 2106 #endif 2107 2108 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2109 EXPORT_SYMBOL(netstamp_needed_key); 2110 #ifdef CONFIG_JUMP_LABEL 2111 static atomic_t netstamp_needed_deferred; 2112 static atomic_t netstamp_wanted; 2113 static void netstamp_clear(struct work_struct *work) 2114 { 2115 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2116 int wanted; 2117 2118 wanted = atomic_add_return(deferred, &netstamp_wanted); 2119 if (wanted > 0) 2120 static_branch_enable(&netstamp_needed_key); 2121 else 2122 static_branch_disable(&netstamp_needed_key); 2123 } 2124 static DECLARE_WORK(netstamp_work, netstamp_clear); 2125 #endif 2126 2127 void net_enable_timestamp(void) 2128 { 2129 #ifdef CONFIG_JUMP_LABEL 2130 int wanted = atomic_read(&netstamp_wanted); 2131 2132 while (wanted > 0) { 2133 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1)) 2134 return; 2135 } 2136 atomic_inc(&netstamp_needed_deferred); 2137 schedule_work(&netstamp_work); 2138 #else 2139 static_branch_inc(&netstamp_needed_key); 2140 #endif 2141 } 2142 EXPORT_SYMBOL(net_enable_timestamp); 2143 2144 void net_disable_timestamp(void) 2145 { 2146 #ifdef CONFIG_JUMP_LABEL 2147 int wanted = atomic_read(&netstamp_wanted); 2148 2149 while (wanted > 1) { 2150 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1)) 2151 return; 2152 } 2153 atomic_dec(&netstamp_needed_deferred); 2154 schedule_work(&netstamp_work); 2155 #else 2156 static_branch_dec(&netstamp_needed_key); 2157 #endif 2158 } 2159 EXPORT_SYMBOL(net_disable_timestamp); 2160 2161 static inline void net_timestamp_set(struct sk_buff *skb) 2162 { 2163 skb->tstamp = 0; 2164 skb->mono_delivery_time = 0; 2165 if (static_branch_unlikely(&netstamp_needed_key)) 2166 skb->tstamp = ktime_get_real(); 2167 } 2168 2169 #define net_timestamp_check(COND, SKB) \ 2170 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2171 if ((COND) && !(SKB)->tstamp) \ 2172 (SKB)->tstamp = ktime_get_real(); \ 2173 } \ 2174 2175 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2176 { 2177 return __is_skb_forwardable(dev, skb, true); 2178 } 2179 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2180 2181 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2182 bool check_mtu) 2183 { 2184 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2185 2186 if (likely(!ret)) { 2187 skb->protocol = eth_type_trans(skb, dev); 2188 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2189 } 2190 2191 return ret; 2192 } 2193 2194 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2195 { 2196 return __dev_forward_skb2(dev, skb, true); 2197 } 2198 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2199 2200 /** 2201 * dev_forward_skb - loopback an skb to another netif 2202 * 2203 * @dev: destination network device 2204 * @skb: buffer to forward 2205 * 2206 * return values: 2207 * NET_RX_SUCCESS (no congestion) 2208 * NET_RX_DROP (packet was dropped, but freed) 2209 * 2210 * dev_forward_skb can be used for injecting an skb from the 2211 * start_xmit function of one device into the receive queue 2212 * of another device. 2213 * 2214 * The receiving device may be in another namespace, so 2215 * we have to clear all information in the skb that could 2216 * impact namespace isolation. 2217 */ 2218 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2219 { 2220 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2221 } 2222 EXPORT_SYMBOL_GPL(dev_forward_skb); 2223 2224 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2225 { 2226 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2227 } 2228 2229 static inline int deliver_skb(struct sk_buff *skb, 2230 struct packet_type *pt_prev, 2231 struct net_device *orig_dev) 2232 { 2233 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2234 return -ENOMEM; 2235 refcount_inc(&skb->users); 2236 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2237 } 2238 2239 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2240 struct packet_type **pt, 2241 struct net_device *orig_dev, 2242 __be16 type, 2243 struct list_head *ptype_list) 2244 { 2245 struct packet_type *ptype, *pt_prev = *pt; 2246 2247 list_for_each_entry_rcu(ptype, ptype_list, list) { 2248 if (ptype->type != type) 2249 continue; 2250 if (pt_prev) 2251 deliver_skb(skb, pt_prev, orig_dev); 2252 pt_prev = ptype; 2253 } 2254 *pt = pt_prev; 2255 } 2256 2257 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2258 { 2259 if (!ptype->af_packet_priv || !skb->sk) 2260 return false; 2261 2262 if (ptype->id_match) 2263 return ptype->id_match(ptype, skb->sk); 2264 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2265 return true; 2266 2267 return false; 2268 } 2269 2270 /** 2271 * dev_nit_active - return true if any network interface taps are in use 2272 * 2273 * @dev: network device to check for the presence of taps 2274 */ 2275 bool dev_nit_active(struct net_device *dev) 2276 { 2277 return !list_empty(&net_hotdata.ptype_all) || 2278 !list_empty(&dev->ptype_all); 2279 } 2280 EXPORT_SYMBOL_GPL(dev_nit_active); 2281 2282 /* 2283 * Support routine. Sends outgoing frames to any network 2284 * taps currently in use. 2285 */ 2286 2287 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2288 { 2289 struct list_head *ptype_list = &net_hotdata.ptype_all; 2290 struct packet_type *ptype, *pt_prev = NULL; 2291 struct sk_buff *skb2 = NULL; 2292 2293 rcu_read_lock(); 2294 again: 2295 list_for_each_entry_rcu(ptype, ptype_list, list) { 2296 if (READ_ONCE(ptype->ignore_outgoing)) 2297 continue; 2298 2299 /* Never send packets back to the socket 2300 * they originated from - MvS (miquels@drinkel.ow.org) 2301 */ 2302 if (skb_loop_sk(ptype, skb)) 2303 continue; 2304 2305 if (pt_prev) { 2306 deliver_skb(skb2, pt_prev, skb->dev); 2307 pt_prev = ptype; 2308 continue; 2309 } 2310 2311 /* need to clone skb, done only once */ 2312 skb2 = skb_clone(skb, GFP_ATOMIC); 2313 if (!skb2) 2314 goto out_unlock; 2315 2316 net_timestamp_set(skb2); 2317 2318 /* skb->nh should be correctly 2319 * set by sender, so that the second statement is 2320 * just protection against buggy protocols. 2321 */ 2322 skb_reset_mac_header(skb2); 2323 2324 if (skb_network_header(skb2) < skb2->data || 2325 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2326 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2327 ntohs(skb2->protocol), 2328 dev->name); 2329 skb_reset_network_header(skb2); 2330 } 2331 2332 skb2->transport_header = skb2->network_header; 2333 skb2->pkt_type = PACKET_OUTGOING; 2334 pt_prev = ptype; 2335 } 2336 2337 if (ptype_list == &net_hotdata.ptype_all) { 2338 ptype_list = &dev->ptype_all; 2339 goto again; 2340 } 2341 out_unlock: 2342 if (pt_prev) { 2343 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2344 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2345 else 2346 kfree_skb(skb2); 2347 } 2348 rcu_read_unlock(); 2349 } 2350 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2351 2352 /** 2353 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2354 * @dev: Network device 2355 * @txq: number of queues available 2356 * 2357 * If real_num_tx_queues is changed the tc mappings may no longer be 2358 * valid. To resolve this verify the tc mapping remains valid and if 2359 * not NULL the mapping. With no priorities mapping to this 2360 * offset/count pair it will no longer be used. In the worst case TC0 2361 * is invalid nothing can be done so disable priority mappings. If is 2362 * expected that drivers will fix this mapping if they can before 2363 * calling netif_set_real_num_tx_queues. 2364 */ 2365 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2366 { 2367 int i; 2368 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2369 2370 /* If TC0 is invalidated disable TC mapping */ 2371 if (tc->offset + tc->count > txq) { 2372 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2373 dev->num_tc = 0; 2374 return; 2375 } 2376 2377 /* Invalidated prio to tc mappings set to TC0 */ 2378 for (i = 1; i < TC_BITMASK + 1; i++) { 2379 int q = netdev_get_prio_tc_map(dev, i); 2380 2381 tc = &dev->tc_to_txq[q]; 2382 if (tc->offset + tc->count > txq) { 2383 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", 2384 i, q); 2385 netdev_set_prio_tc_map(dev, i, 0); 2386 } 2387 } 2388 } 2389 2390 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2391 { 2392 if (dev->num_tc) { 2393 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2394 int i; 2395 2396 /* walk through the TCs and see if it falls into any of them */ 2397 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2398 if ((txq - tc->offset) < tc->count) 2399 return i; 2400 } 2401 2402 /* didn't find it, just return -1 to indicate no match */ 2403 return -1; 2404 } 2405 2406 return 0; 2407 } 2408 EXPORT_SYMBOL(netdev_txq_to_tc); 2409 2410 #ifdef CONFIG_XPS 2411 static struct static_key xps_needed __read_mostly; 2412 static struct static_key xps_rxqs_needed __read_mostly; 2413 static DEFINE_MUTEX(xps_map_mutex); 2414 #define xmap_dereference(P) \ 2415 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2416 2417 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2418 struct xps_dev_maps *old_maps, int tci, u16 index) 2419 { 2420 struct xps_map *map = NULL; 2421 int pos; 2422 2423 map = xmap_dereference(dev_maps->attr_map[tci]); 2424 if (!map) 2425 return false; 2426 2427 for (pos = map->len; pos--;) { 2428 if (map->queues[pos] != index) 2429 continue; 2430 2431 if (map->len > 1) { 2432 map->queues[pos] = map->queues[--map->len]; 2433 break; 2434 } 2435 2436 if (old_maps) 2437 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2438 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2439 kfree_rcu(map, rcu); 2440 return false; 2441 } 2442 2443 return true; 2444 } 2445 2446 static bool remove_xps_queue_cpu(struct net_device *dev, 2447 struct xps_dev_maps *dev_maps, 2448 int cpu, u16 offset, u16 count) 2449 { 2450 int num_tc = dev_maps->num_tc; 2451 bool active = false; 2452 int tci; 2453 2454 for (tci = cpu * num_tc; num_tc--; tci++) { 2455 int i, j; 2456 2457 for (i = count, j = offset; i--; j++) { 2458 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2459 break; 2460 } 2461 2462 active |= i < 0; 2463 } 2464 2465 return active; 2466 } 2467 2468 static void reset_xps_maps(struct net_device *dev, 2469 struct xps_dev_maps *dev_maps, 2470 enum xps_map_type type) 2471 { 2472 static_key_slow_dec_cpuslocked(&xps_needed); 2473 if (type == XPS_RXQS) 2474 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2475 2476 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2477 2478 kfree_rcu(dev_maps, rcu); 2479 } 2480 2481 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2482 u16 offset, u16 count) 2483 { 2484 struct xps_dev_maps *dev_maps; 2485 bool active = false; 2486 int i, j; 2487 2488 dev_maps = xmap_dereference(dev->xps_maps[type]); 2489 if (!dev_maps) 2490 return; 2491 2492 for (j = 0; j < dev_maps->nr_ids; j++) 2493 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2494 if (!active) 2495 reset_xps_maps(dev, dev_maps, type); 2496 2497 if (type == XPS_CPUS) { 2498 for (i = offset + (count - 1); count--; i--) 2499 netdev_queue_numa_node_write( 2500 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2501 } 2502 } 2503 2504 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2505 u16 count) 2506 { 2507 if (!static_key_false(&xps_needed)) 2508 return; 2509 2510 cpus_read_lock(); 2511 mutex_lock(&xps_map_mutex); 2512 2513 if (static_key_false(&xps_rxqs_needed)) 2514 clean_xps_maps(dev, XPS_RXQS, offset, count); 2515 2516 clean_xps_maps(dev, XPS_CPUS, offset, count); 2517 2518 mutex_unlock(&xps_map_mutex); 2519 cpus_read_unlock(); 2520 } 2521 2522 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2523 { 2524 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2525 } 2526 2527 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2528 u16 index, bool is_rxqs_map) 2529 { 2530 struct xps_map *new_map; 2531 int alloc_len = XPS_MIN_MAP_ALLOC; 2532 int i, pos; 2533 2534 for (pos = 0; map && pos < map->len; pos++) { 2535 if (map->queues[pos] != index) 2536 continue; 2537 return map; 2538 } 2539 2540 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2541 if (map) { 2542 if (pos < map->alloc_len) 2543 return map; 2544 2545 alloc_len = map->alloc_len * 2; 2546 } 2547 2548 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2549 * map 2550 */ 2551 if (is_rxqs_map) 2552 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2553 else 2554 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2555 cpu_to_node(attr_index)); 2556 if (!new_map) 2557 return NULL; 2558 2559 for (i = 0; i < pos; i++) 2560 new_map->queues[i] = map->queues[i]; 2561 new_map->alloc_len = alloc_len; 2562 new_map->len = pos; 2563 2564 return new_map; 2565 } 2566 2567 /* Copy xps maps at a given index */ 2568 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2569 struct xps_dev_maps *new_dev_maps, int index, 2570 int tc, bool skip_tc) 2571 { 2572 int i, tci = index * dev_maps->num_tc; 2573 struct xps_map *map; 2574 2575 /* copy maps belonging to foreign traffic classes */ 2576 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2577 if (i == tc && skip_tc) 2578 continue; 2579 2580 /* fill in the new device map from the old device map */ 2581 map = xmap_dereference(dev_maps->attr_map[tci]); 2582 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2583 } 2584 } 2585 2586 /* Must be called under cpus_read_lock */ 2587 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2588 u16 index, enum xps_map_type type) 2589 { 2590 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2591 const unsigned long *online_mask = NULL; 2592 bool active = false, copy = false; 2593 int i, j, tci, numa_node_id = -2; 2594 int maps_sz, num_tc = 1, tc = 0; 2595 struct xps_map *map, *new_map; 2596 unsigned int nr_ids; 2597 2598 WARN_ON_ONCE(index >= dev->num_tx_queues); 2599 2600 if (dev->num_tc) { 2601 /* Do not allow XPS on subordinate device directly */ 2602 num_tc = dev->num_tc; 2603 if (num_tc < 0) 2604 return -EINVAL; 2605 2606 /* If queue belongs to subordinate dev use its map */ 2607 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2608 2609 tc = netdev_txq_to_tc(dev, index); 2610 if (tc < 0) 2611 return -EINVAL; 2612 } 2613 2614 mutex_lock(&xps_map_mutex); 2615 2616 dev_maps = xmap_dereference(dev->xps_maps[type]); 2617 if (type == XPS_RXQS) { 2618 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2619 nr_ids = dev->num_rx_queues; 2620 } else { 2621 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2622 if (num_possible_cpus() > 1) 2623 online_mask = cpumask_bits(cpu_online_mask); 2624 nr_ids = nr_cpu_ids; 2625 } 2626 2627 if (maps_sz < L1_CACHE_BYTES) 2628 maps_sz = L1_CACHE_BYTES; 2629 2630 /* The old dev_maps could be larger or smaller than the one we're 2631 * setting up now, as dev->num_tc or nr_ids could have been updated in 2632 * between. We could try to be smart, but let's be safe instead and only 2633 * copy foreign traffic classes if the two map sizes match. 2634 */ 2635 if (dev_maps && 2636 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2637 copy = true; 2638 2639 /* allocate memory for queue storage */ 2640 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2641 j < nr_ids;) { 2642 if (!new_dev_maps) { 2643 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2644 if (!new_dev_maps) { 2645 mutex_unlock(&xps_map_mutex); 2646 return -ENOMEM; 2647 } 2648 2649 new_dev_maps->nr_ids = nr_ids; 2650 new_dev_maps->num_tc = num_tc; 2651 } 2652 2653 tci = j * num_tc + tc; 2654 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2655 2656 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2657 if (!map) 2658 goto error; 2659 2660 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2661 } 2662 2663 if (!new_dev_maps) 2664 goto out_no_new_maps; 2665 2666 if (!dev_maps) { 2667 /* Increment static keys at most once per type */ 2668 static_key_slow_inc_cpuslocked(&xps_needed); 2669 if (type == XPS_RXQS) 2670 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2671 } 2672 2673 for (j = 0; j < nr_ids; j++) { 2674 bool skip_tc = false; 2675 2676 tci = j * num_tc + tc; 2677 if (netif_attr_test_mask(j, mask, nr_ids) && 2678 netif_attr_test_online(j, online_mask, nr_ids)) { 2679 /* add tx-queue to CPU/rx-queue maps */ 2680 int pos = 0; 2681 2682 skip_tc = true; 2683 2684 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2685 while ((pos < map->len) && (map->queues[pos] != index)) 2686 pos++; 2687 2688 if (pos == map->len) 2689 map->queues[map->len++] = index; 2690 #ifdef CONFIG_NUMA 2691 if (type == XPS_CPUS) { 2692 if (numa_node_id == -2) 2693 numa_node_id = cpu_to_node(j); 2694 else if (numa_node_id != cpu_to_node(j)) 2695 numa_node_id = -1; 2696 } 2697 #endif 2698 } 2699 2700 if (copy) 2701 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2702 skip_tc); 2703 } 2704 2705 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2706 2707 /* Cleanup old maps */ 2708 if (!dev_maps) 2709 goto out_no_old_maps; 2710 2711 for (j = 0; j < dev_maps->nr_ids; j++) { 2712 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2713 map = xmap_dereference(dev_maps->attr_map[tci]); 2714 if (!map) 2715 continue; 2716 2717 if (copy) { 2718 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2719 if (map == new_map) 2720 continue; 2721 } 2722 2723 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2724 kfree_rcu(map, rcu); 2725 } 2726 } 2727 2728 old_dev_maps = dev_maps; 2729 2730 out_no_old_maps: 2731 dev_maps = new_dev_maps; 2732 active = true; 2733 2734 out_no_new_maps: 2735 if (type == XPS_CPUS) 2736 /* update Tx queue numa node */ 2737 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2738 (numa_node_id >= 0) ? 2739 numa_node_id : NUMA_NO_NODE); 2740 2741 if (!dev_maps) 2742 goto out_no_maps; 2743 2744 /* removes tx-queue from unused CPUs/rx-queues */ 2745 for (j = 0; j < dev_maps->nr_ids; j++) { 2746 tci = j * dev_maps->num_tc; 2747 2748 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2749 if (i == tc && 2750 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2751 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2752 continue; 2753 2754 active |= remove_xps_queue(dev_maps, 2755 copy ? old_dev_maps : NULL, 2756 tci, index); 2757 } 2758 } 2759 2760 if (old_dev_maps) 2761 kfree_rcu(old_dev_maps, rcu); 2762 2763 /* free map if not active */ 2764 if (!active) 2765 reset_xps_maps(dev, dev_maps, type); 2766 2767 out_no_maps: 2768 mutex_unlock(&xps_map_mutex); 2769 2770 return 0; 2771 error: 2772 /* remove any maps that we added */ 2773 for (j = 0; j < nr_ids; j++) { 2774 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2775 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2776 map = copy ? 2777 xmap_dereference(dev_maps->attr_map[tci]) : 2778 NULL; 2779 if (new_map && new_map != map) 2780 kfree(new_map); 2781 } 2782 } 2783 2784 mutex_unlock(&xps_map_mutex); 2785 2786 kfree(new_dev_maps); 2787 return -ENOMEM; 2788 } 2789 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2790 2791 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2792 u16 index) 2793 { 2794 int ret; 2795 2796 cpus_read_lock(); 2797 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2798 cpus_read_unlock(); 2799 2800 return ret; 2801 } 2802 EXPORT_SYMBOL(netif_set_xps_queue); 2803 2804 #endif 2805 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2806 { 2807 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2808 2809 /* Unbind any subordinate channels */ 2810 while (txq-- != &dev->_tx[0]) { 2811 if (txq->sb_dev) 2812 netdev_unbind_sb_channel(dev, txq->sb_dev); 2813 } 2814 } 2815 2816 void netdev_reset_tc(struct net_device *dev) 2817 { 2818 #ifdef CONFIG_XPS 2819 netif_reset_xps_queues_gt(dev, 0); 2820 #endif 2821 netdev_unbind_all_sb_channels(dev); 2822 2823 /* Reset TC configuration of device */ 2824 dev->num_tc = 0; 2825 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2826 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2827 } 2828 EXPORT_SYMBOL(netdev_reset_tc); 2829 2830 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2831 { 2832 if (tc >= dev->num_tc) 2833 return -EINVAL; 2834 2835 #ifdef CONFIG_XPS 2836 netif_reset_xps_queues(dev, offset, count); 2837 #endif 2838 dev->tc_to_txq[tc].count = count; 2839 dev->tc_to_txq[tc].offset = offset; 2840 return 0; 2841 } 2842 EXPORT_SYMBOL(netdev_set_tc_queue); 2843 2844 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2845 { 2846 if (num_tc > TC_MAX_QUEUE) 2847 return -EINVAL; 2848 2849 #ifdef CONFIG_XPS 2850 netif_reset_xps_queues_gt(dev, 0); 2851 #endif 2852 netdev_unbind_all_sb_channels(dev); 2853 2854 dev->num_tc = num_tc; 2855 return 0; 2856 } 2857 EXPORT_SYMBOL(netdev_set_num_tc); 2858 2859 void netdev_unbind_sb_channel(struct net_device *dev, 2860 struct net_device *sb_dev) 2861 { 2862 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2863 2864 #ifdef CONFIG_XPS 2865 netif_reset_xps_queues_gt(sb_dev, 0); 2866 #endif 2867 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2868 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2869 2870 while (txq-- != &dev->_tx[0]) { 2871 if (txq->sb_dev == sb_dev) 2872 txq->sb_dev = NULL; 2873 } 2874 } 2875 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2876 2877 int netdev_bind_sb_channel_queue(struct net_device *dev, 2878 struct net_device *sb_dev, 2879 u8 tc, u16 count, u16 offset) 2880 { 2881 /* Make certain the sb_dev and dev are already configured */ 2882 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2883 return -EINVAL; 2884 2885 /* We cannot hand out queues we don't have */ 2886 if ((offset + count) > dev->real_num_tx_queues) 2887 return -EINVAL; 2888 2889 /* Record the mapping */ 2890 sb_dev->tc_to_txq[tc].count = count; 2891 sb_dev->tc_to_txq[tc].offset = offset; 2892 2893 /* Provide a way for Tx queue to find the tc_to_txq map or 2894 * XPS map for itself. 2895 */ 2896 while (count--) 2897 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2898 2899 return 0; 2900 } 2901 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2902 2903 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2904 { 2905 /* Do not use a multiqueue device to represent a subordinate channel */ 2906 if (netif_is_multiqueue(dev)) 2907 return -ENODEV; 2908 2909 /* We allow channels 1 - 32767 to be used for subordinate channels. 2910 * Channel 0 is meant to be "native" mode and used only to represent 2911 * the main root device. We allow writing 0 to reset the device back 2912 * to normal mode after being used as a subordinate channel. 2913 */ 2914 if (channel > S16_MAX) 2915 return -EINVAL; 2916 2917 dev->num_tc = -channel; 2918 2919 return 0; 2920 } 2921 EXPORT_SYMBOL(netdev_set_sb_channel); 2922 2923 /* 2924 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2925 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2926 */ 2927 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2928 { 2929 bool disabling; 2930 int rc; 2931 2932 disabling = txq < dev->real_num_tx_queues; 2933 2934 if (txq < 1 || txq > dev->num_tx_queues) 2935 return -EINVAL; 2936 2937 if (dev->reg_state == NETREG_REGISTERED || 2938 dev->reg_state == NETREG_UNREGISTERING) { 2939 ASSERT_RTNL(); 2940 2941 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2942 txq); 2943 if (rc) 2944 return rc; 2945 2946 if (dev->num_tc) 2947 netif_setup_tc(dev, txq); 2948 2949 dev_qdisc_change_real_num_tx(dev, txq); 2950 2951 dev->real_num_tx_queues = txq; 2952 2953 if (disabling) { 2954 synchronize_net(); 2955 qdisc_reset_all_tx_gt(dev, txq); 2956 #ifdef CONFIG_XPS 2957 netif_reset_xps_queues_gt(dev, txq); 2958 #endif 2959 } 2960 } else { 2961 dev->real_num_tx_queues = txq; 2962 } 2963 2964 return 0; 2965 } 2966 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2967 2968 #ifdef CONFIG_SYSFS 2969 /** 2970 * netif_set_real_num_rx_queues - set actual number of RX queues used 2971 * @dev: Network device 2972 * @rxq: Actual number of RX queues 2973 * 2974 * This must be called either with the rtnl_lock held or before 2975 * registration of the net device. Returns 0 on success, or a 2976 * negative error code. If called before registration, it always 2977 * succeeds. 2978 */ 2979 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2980 { 2981 int rc; 2982 2983 if (rxq < 1 || rxq > dev->num_rx_queues) 2984 return -EINVAL; 2985 2986 if (dev->reg_state == NETREG_REGISTERED) { 2987 ASSERT_RTNL(); 2988 2989 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2990 rxq); 2991 if (rc) 2992 return rc; 2993 } 2994 2995 dev->real_num_rx_queues = rxq; 2996 return 0; 2997 } 2998 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2999 #endif 3000 3001 /** 3002 * netif_set_real_num_queues - set actual number of RX and TX queues used 3003 * @dev: Network device 3004 * @txq: Actual number of TX queues 3005 * @rxq: Actual number of RX queues 3006 * 3007 * Set the real number of both TX and RX queues. 3008 * Does nothing if the number of queues is already correct. 3009 */ 3010 int netif_set_real_num_queues(struct net_device *dev, 3011 unsigned int txq, unsigned int rxq) 3012 { 3013 unsigned int old_rxq = dev->real_num_rx_queues; 3014 int err; 3015 3016 if (txq < 1 || txq > dev->num_tx_queues || 3017 rxq < 1 || rxq > dev->num_rx_queues) 3018 return -EINVAL; 3019 3020 /* Start from increases, so the error path only does decreases - 3021 * decreases can't fail. 3022 */ 3023 if (rxq > dev->real_num_rx_queues) { 3024 err = netif_set_real_num_rx_queues(dev, rxq); 3025 if (err) 3026 return err; 3027 } 3028 if (txq > dev->real_num_tx_queues) { 3029 err = netif_set_real_num_tx_queues(dev, txq); 3030 if (err) 3031 goto undo_rx; 3032 } 3033 if (rxq < dev->real_num_rx_queues) 3034 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 3035 if (txq < dev->real_num_tx_queues) 3036 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 3037 3038 return 0; 3039 undo_rx: 3040 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 3041 return err; 3042 } 3043 EXPORT_SYMBOL(netif_set_real_num_queues); 3044 3045 /** 3046 * netif_set_tso_max_size() - set the max size of TSO frames supported 3047 * @dev: netdev to update 3048 * @size: max skb->len of a TSO frame 3049 * 3050 * Set the limit on the size of TSO super-frames the device can handle. 3051 * Unless explicitly set the stack will assume the value of 3052 * %GSO_LEGACY_MAX_SIZE. 3053 */ 3054 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3055 { 3056 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3057 if (size < READ_ONCE(dev->gso_max_size)) 3058 netif_set_gso_max_size(dev, size); 3059 if (size < READ_ONCE(dev->gso_ipv4_max_size)) 3060 netif_set_gso_ipv4_max_size(dev, size); 3061 } 3062 EXPORT_SYMBOL(netif_set_tso_max_size); 3063 3064 /** 3065 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3066 * @dev: netdev to update 3067 * @segs: max number of TCP segments 3068 * 3069 * Set the limit on the number of TCP segments the device can generate from 3070 * a single TSO super-frame. 3071 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3072 */ 3073 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3074 { 3075 dev->tso_max_segs = segs; 3076 if (segs < READ_ONCE(dev->gso_max_segs)) 3077 netif_set_gso_max_segs(dev, segs); 3078 } 3079 EXPORT_SYMBOL(netif_set_tso_max_segs); 3080 3081 /** 3082 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3083 * @to: netdev to update 3084 * @from: netdev from which to copy the limits 3085 */ 3086 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3087 { 3088 netif_set_tso_max_size(to, from->tso_max_size); 3089 netif_set_tso_max_segs(to, from->tso_max_segs); 3090 } 3091 EXPORT_SYMBOL(netif_inherit_tso_max); 3092 3093 /** 3094 * netif_get_num_default_rss_queues - default number of RSS queues 3095 * 3096 * Default value is the number of physical cores if there are only 1 or 2, or 3097 * divided by 2 if there are more. 3098 */ 3099 int netif_get_num_default_rss_queues(void) 3100 { 3101 cpumask_var_t cpus; 3102 int cpu, count = 0; 3103 3104 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3105 return 1; 3106 3107 cpumask_copy(cpus, cpu_online_mask); 3108 for_each_cpu(cpu, cpus) { 3109 ++count; 3110 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3111 } 3112 free_cpumask_var(cpus); 3113 3114 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3115 } 3116 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3117 3118 static void __netif_reschedule(struct Qdisc *q) 3119 { 3120 struct softnet_data *sd; 3121 unsigned long flags; 3122 3123 local_irq_save(flags); 3124 sd = this_cpu_ptr(&softnet_data); 3125 q->next_sched = NULL; 3126 *sd->output_queue_tailp = q; 3127 sd->output_queue_tailp = &q->next_sched; 3128 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3129 local_irq_restore(flags); 3130 } 3131 3132 void __netif_schedule(struct Qdisc *q) 3133 { 3134 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3135 __netif_reschedule(q); 3136 } 3137 EXPORT_SYMBOL(__netif_schedule); 3138 3139 struct dev_kfree_skb_cb { 3140 enum skb_drop_reason reason; 3141 }; 3142 3143 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3144 { 3145 return (struct dev_kfree_skb_cb *)skb->cb; 3146 } 3147 3148 void netif_schedule_queue(struct netdev_queue *txq) 3149 { 3150 rcu_read_lock(); 3151 if (!netif_xmit_stopped(txq)) { 3152 struct Qdisc *q = rcu_dereference(txq->qdisc); 3153 3154 __netif_schedule(q); 3155 } 3156 rcu_read_unlock(); 3157 } 3158 EXPORT_SYMBOL(netif_schedule_queue); 3159 3160 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3161 { 3162 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3163 struct Qdisc *q; 3164 3165 rcu_read_lock(); 3166 q = rcu_dereference(dev_queue->qdisc); 3167 __netif_schedule(q); 3168 rcu_read_unlock(); 3169 } 3170 } 3171 EXPORT_SYMBOL(netif_tx_wake_queue); 3172 3173 void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3174 { 3175 unsigned long flags; 3176 3177 if (unlikely(!skb)) 3178 return; 3179 3180 if (likely(refcount_read(&skb->users) == 1)) { 3181 smp_rmb(); 3182 refcount_set(&skb->users, 0); 3183 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3184 return; 3185 } 3186 get_kfree_skb_cb(skb)->reason = reason; 3187 local_irq_save(flags); 3188 skb->next = __this_cpu_read(softnet_data.completion_queue); 3189 __this_cpu_write(softnet_data.completion_queue, skb); 3190 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3191 local_irq_restore(flags); 3192 } 3193 EXPORT_SYMBOL(dev_kfree_skb_irq_reason); 3194 3195 void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3196 { 3197 if (in_hardirq() || irqs_disabled()) 3198 dev_kfree_skb_irq_reason(skb, reason); 3199 else 3200 kfree_skb_reason(skb, reason); 3201 } 3202 EXPORT_SYMBOL(dev_kfree_skb_any_reason); 3203 3204 3205 /** 3206 * netif_device_detach - mark device as removed 3207 * @dev: network device 3208 * 3209 * Mark device as removed from system and therefore no longer available. 3210 */ 3211 void netif_device_detach(struct net_device *dev) 3212 { 3213 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3214 netif_running(dev)) { 3215 netif_tx_stop_all_queues(dev); 3216 } 3217 } 3218 EXPORT_SYMBOL(netif_device_detach); 3219 3220 /** 3221 * netif_device_attach - mark device as attached 3222 * @dev: network device 3223 * 3224 * Mark device as attached from system and restart if needed. 3225 */ 3226 void netif_device_attach(struct net_device *dev) 3227 { 3228 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3229 netif_running(dev)) { 3230 netif_tx_wake_all_queues(dev); 3231 __netdev_watchdog_up(dev); 3232 } 3233 } 3234 EXPORT_SYMBOL(netif_device_attach); 3235 3236 /* 3237 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3238 * to be used as a distribution range. 3239 */ 3240 static u16 skb_tx_hash(const struct net_device *dev, 3241 const struct net_device *sb_dev, 3242 struct sk_buff *skb) 3243 { 3244 u32 hash; 3245 u16 qoffset = 0; 3246 u16 qcount = dev->real_num_tx_queues; 3247 3248 if (dev->num_tc) { 3249 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3250 3251 qoffset = sb_dev->tc_to_txq[tc].offset; 3252 qcount = sb_dev->tc_to_txq[tc].count; 3253 if (unlikely(!qcount)) { 3254 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3255 sb_dev->name, qoffset, tc); 3256 qoffset = 0; 3257 qcount = dev->real_num_tx_queues; 3258 } 3259 } 3260 3261 if (skb_rx_queue_recorded(skb)) { 3262 DEBUG_NET_WARN_ON_ONCE(qcount == 0); 3263 hash = skb_get_rx_queue(skb); 3264 if (hash >= qoffset) 3265 hash -= qoffset; 3266 while (unlikely(hash >= qcount)) 3267 hash -= qcount; 3268 return hash + qoffset; 3269 } 3270 3271 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3272 } 3273 3274 void skb_warn_bad_offload(const struct sk_buff *skb) 3275 { 3276 static const netdev_features_t null_features; 3277 struct net_device *dev = skb->dev; 3278 const char *name = ""; 3279 3280 if (!net_ratelimit()) 3281 return; 3282 3283 if (dev) { 3284 if (dev->dev.parent) 3285 name = dev_driver_string(dev->dev.parent); 3286 else 3287 name = netdev_name(dev); 3288 } 3289 skb_dump(KERN_WARNING, skb, false); 3290 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3291 name, dev ? &dev->features : &null_features, 3292 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3293 } 3294 3295 /* 3296 * Invalidate hardware checksum when packet is to be mangled, and 3297 * complete checksum manually on outgoing path. 3298 */ 3299 int skb_checksum_help(struct sk_buff *skb) 3300 { 3301 __wsum csum; 3302 int ret = 0, offset; 3303 3304 if (skb->ip_summed == CHECKSUM_COMPLETE) 3305 goto out_set_summed; 3306 3307 if (unlikely(skb_is_gso(skb))) { 3308 skb_warn_bad_offload(skb); 3309 return -EINVAL; 3310 } 3311 3312 /* Before computing a checksum, we should make sure no frag could 3313 * be modified by an external entity : checksum could be wrong. 3314 */ 3315 if (skb_has_shared_frag(skb)) { 3316 ret = __skb_linearize(skb); 3317 if (ret) 3318 goto out; 3319 } 3320 3321 offset = skb_checksum_start_offset(skb); 3322 ret = -EINVAL; 3323 if (unlikely(offset >= skb_headlen(skb))) { 3324 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3325 WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n", 3326 offset, skb_headlen(skb)); 3327 goto out; 3328 } 3329 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3330 3331 offset += skb->csum_offset; 3332 if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) { 3333 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3334 WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n", 3335 offset + sizeof(__sum16), skb_headlen(skb)); 3336 goto out; 3337 } 3338 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3339 if (ret) 3340 goto out; 3341 3342 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3343 out_set_summed: 3344 skb->ip_summed = CHECKSUM_NONE; 3345 out: 3346 return ret; 3347 } 3348 EXPORT_SYMBOL(skb_checksum_help); 3349 3350 int skb_crc32c_csum_help(struct sk_buff *skb) 3351 { 3352 __le32 crc32c_csum; 3353 int ret = 0, offset, start; 3354 3355 if (skb->ip_summed != CHECKSUM_PARTIAL) 3356 goto out; 3357 3358 if (unlikely(skb_is_gso(skb))) 3359 goto out; 3360 3361 /* Before computing a checksum, we should make sure no frag could 3362 * be modified by an external entity : checksum could be wrong. 3363 */ 3364 if (unlikely(skb_has_shared_frag(skb))) { 3365 ret = __skb_linearize(skb); 3366 if (ret) 3367 goto out; 3368 } 3369 start = skb_checksum_start_offset(skb); 3370 offset = start + offsetof(struct sctphdr, checksum); 3371 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3372 ret = -EINVAL; 3373 goto out; 3374 } 3375 3376 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3377 if (ret) 3378 goto out; 3379 3380 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3381 skb->len - start, ~(__u32)0, 3382 crc32c_csum_stub)); 3383 *(__le32 *)(skb->data + offset) = crc32c_csum; 3384 skb_reset_csum_not_inet(skb); 3385 out: 3386 return ret; 3387 } 3388 3389 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3390 { 3391 __be16 type = skb->protocol; 3392 3393 /* Tunnel gso handlers can set protocol to ethernet. */ 3394 if (type == htons(ETH_P_TEB)) { 3395 struct ethhdr *eth; 3396 3397 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3398 return 0; 3399 3400 eth = (struct ethhdr *)skb->data; 3401 type = eth->h_proto; 3402 } 3403 3404 return vlan_get_protocol_and_depth(skb, type, depth); 3405 } 3406 3407 3408 /* Take action when hardware reception checksum errors are detected. */ 3409 #ifdef CONFIG_BUG 3410 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3411 { 3412 netdev_err(dev, "hw csum failure\n"); 3413 skb_dump(KERN_ERR, skb, true); 3414 dump_stack(); 3415 } 3416 3417 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3418 { 3419 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3420 } 3421 EXPORT_SYMBOL(netdev_rx_csum_fault); 3422 #endif 3423 3424 /* XXX: check that highmem exists at all on the given machine. */ 3425 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3426 { 3427 #ifdef CONFIG_HIGHMEM 3428 int i; 3429 3430 if (!(dev->features & NETIF_F_HIGHDMA)) { 3431 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3432 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3433 3434 if (PageHighMem(skb_frag_page(frag))) 3435 return 1; 3436 } 3437 } 3438 #endif 3439 return 0; 3440 } 3441 3442 /* If MPLS offload request, verify we are testing hardware MPLS features 3443 * instead of standard features for the netdev. 3444 */ 3445 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3446 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3447 netdev_features_t features, 3448 __be16 type) 3449 { 3450 if (eth_p_mpls(type)) 3451 features &= skb->dev->mpls_features; 3452 3453 return features; 3454 } 3455 #else 3456 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3457 netdev_features_t features, 3458 __be16 type) 3459 { 3460 return features; 3461 } 3462 #endif 3463 3464 static netdev_features_t harmonize_features(struct sk_buff *skb, 3465 netdev_features_t features) 3466 { 3467 __be16 type; 3468 3469 type = skb_network_protocol(skb, NULL); 3470 features = net_mpls_features(skb, features, type); 3471 3472 if (skb->ip_summed != CHECKSUM_NONE && 3473 !can_checksum_protocol(features, type)) { 3474 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3475 } 3476 if (illegal_highdma(skb->dev, skb)) 3477 features &= ~NETIF_F_SG; 3478 3479 return features; 3480 } 3481 3482 netdev_features_t passthru_features_check(struct sk_buff *skb, 3483 struct net_device *dev, 3484 netdev_features_t features) 3485 { 3486 return features; 3487 } 3488 EXPORT_SYMBOL(passthru_features_check); 3489 3490 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3491 struct net_device *dev, 3492 netdev_features_t features) 3493 { 3494 return vlan_features_check(skb, features); 3495 } 3496 3497 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3498 struct net_device *dev, 3499 netdev_features_t features) 3500 { 3501 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3502 3503 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3504 return features & ~NETIF_F_GSO_MASK; 3505 3506 if (unlikely(skb->len >= READ_ONCE(dev->gso_max_size))) 3507 return features & ~NETIF_F_GSO_MASK; 3508 3509 if (!skb_shinfo(skb)->gso_type) { 3510 skb_warn_bad_offload(skb); 3511 return features & ~NETIF_F_GSO_MASK; 3512 } 3513 3514 /* Support for GSO partial features requires software 3515 * intervention before we can actually process the packets 3516 * so we need to strip support for any partial features now 3517 * and we can pull them back in after we have partially 3518 * segmented the frame. 3519 */ 3520 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3521 features &= ~dev->gso_partial_features; 3522 3523 /* Make sure to clear the IPv4 ID mangling feature if the 3524 * IPv4 header has the potential to be fragmented. 3525 */ 3526 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3527 struct iphdr *iph = skb->encapsulation ? 3528 inner_ip_hdr(skb) : ip_hdr(skb); 3529 3530 if (!(iph->frag_off & htons(IP_DF))) 3531 features &= ~NETIF_F_TSO_MANGLEID; 3532 } 3533 3534 return features; 3535 } 3536 3537 netdev_features_t netif_skb_features(struct sk_buff *skb) 3538 { 3539 struct net_device *dev = skb->dev; 3540 netdev_features_t features = dev->features; 3541 3542 if (skb_is_gso(skb)) 3543 features = gso_features_check(skb, dev, features); 3544 3545 /* If encapsulation offload request, verify we are testing 3546 * hardware encapsulation features instead of standard 3547 * features for the netdev 3548 */ 3549 if (skb->encapsulation) 3550 features &= dev->hw_enc_features; 3551 3552 if (skb_vlan_tagged(skb)) 3553 features = netdev_intersect_features(features, 3554 dev->vlan_features | 3555 NETIF_F_HW_VLAN_CTAG_TX | 3556 NETIF_F_HW_VLAN_STAG_TX); 3557 3558 if (dev->netdev_ops->ndo_features_check) 3559 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3560 features); 3561 else 3562 features &= dflt_features_check(skb, dev, features); 3563 3564 return harmonize_features(skb, features); 3565 } 3566 EXPORT_SYMBOL(netif_skb_features); 3567 3568 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3569 struct netdev_queue *txq, bool more) 3570 { 3571 unsigned int len; 3572 int rc; 3573 3574 if (dev_nit_active(dev)) 3575 dev_queue_xmit_nit(skb, dev); 3576 3577 len = skb->len; 3578 trace_net_dev_start_xmit(skb, dev); 3579 rc = netdev_start_xmit(skb, dev, txq, more); 3580 trace_net_dev_xmit(skb, rc, dev, len); 3581 3582 return rc; 3583 } 3584 3585 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3586 struct netdev_queue *txq, int *ret) 3587 { 3588 struct sk_buff *skb = first; 3589 int rc = NETDEV_TX_OK; 3590 3591 while (skb) { 3592 struct sk_buff *next = skb->next; 3593 3594 skb_mark_not_on_list(skb); 3595 rc = xmit_one(skb, dev, txq, next != NULL); 3596 if (unlikely(!dev_xmit_complete(rc))) { 3597 skb->next = next; 3598 goto out; 3599 } 3600 3601 skb = next; 3602 if (netif_tx_queue_stopped(txq) && skb) { 3603 rc = NETDEV_TX_BUSY; 3604 break; 3605 } 3606 } 3607 3608 out: 3609 *ret = rc; 3610 return skb; 3611 } 3612 3613 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3614 netdev_features_t features) 3615 { 3616 if (skb_vlan_tag_present(skb) && 3617 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3618 skb = __vlan_hwaccel_push_inside(skb); 3619 return skb; 3620 } 3621 3622 int skb_csum_hwoffload_help(struct sk_buff *skb, 3623 const netdev_features_t features) 3624 { 3625 if (unlikely(skb_csum_is_sctp(skb))) 3626 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3627 skb_crc32c_csum_help(skb); 3628 3629 if (features & NETIF_F_HW_CSUM) 3630 return 0; 3631 3632 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3633 switch (skb->csum_offset) { 3634 case offsetof(struct tcphdr, check): 3635 case offsetof(struct udphdr, check): 3636 return 0; 3637 } 3638 } 3639 3640 return skb_checksum_help(skb); 3641 } 3642 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3643 3644 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3645 { 3646 netdev_features_t features; 3647 3648 features = netif_skb_features(skb); 3649 skb = validate_xmit_vlan(skb, features); 3650 if (unlikely(!skb)) 3651 goto out_null; 3652 3653 skb = sk_validate_xmit_skb(skb, dev); 3654 if (unlikely(!skb)) 3655 goto out_null; 3656 3657 if (netif_needs_gso(skb, features)) { 3658 struct sk_buff *segs; 3659 3660 segs = skb_gso_segment(skb, features); 3661 if (IS_ERR(segs)) { 3662 goto out_kfree_skb; 3663 } else if (segs) { 3664 consume_skb(skb); 3665 skb = segs; 3666 } 3667 } else { 3668 if (skb_needs_linearize(skb, features) && 3669 __skb_linearize(skb)) 3670 goto out_kfree_skb; 3671 3672 /* If packet is not checksummed and device does not 3673 * support checksumming for this protocol, complete 3674 * checksumming here. 3675 */ 3676 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3677 if (skb->encapsulation) 3678 skb_set_inner_transport_header(skb, 3679 skb_checksum_start_offset(skb)); 3680 else 3681 skb_set_transport_header(skb, 3682 skb_checksum_start_offset(skb)); 3683 if (skb_csum_hwoffload_help(skb, features)) 3684 goto out_kfree_skb; 3685 } 3686 } 3687 3688 skb = validate_xmit_xfrm(skb, features, again); 3689 3690 return skb; 3691 3692 out_kfree_skb: 3693 kfree_skb(skb); 3694 out_null: 3695 dev_core_stats_tx_dropped_inc(dev); 3696 return NULL; 3697 } 3698 3699 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3700 { 3701 struct sk_buff *next, *head = NULL, *tail; 3702 3703 for (; skb != NULL; skb = next) { 3704 next = skb->next; 3705 skb_mark_not_on_list(skb); 3706 3707 /* in case skb wont be segmented, point to itself */ 3708 skb->prev = skb; 3709 3710 skb = validate_xmit_skb(skb, dev, again); 3711 if (!skb) 3712 continue; 3713 3714 if (!head) 3715 head = skb; 3716 else 3717 tail->next = skb; 3718 /* If skb was segmented, skb->prev points to 3719 * the last segment. If not, it still contains skb. 3720 */ 3721 tail = skb->prev; 3722 } 3723 return head; 3724 } 3725 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3726 3727 static void qdisc_pkt_len_init(struct sk_buff *skb) 3728 { 3729 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3730 3731 qdisc_skb_cb(skb)->pkt_len = skb->len; 3732 3733 /* To get more precise estimation of bytes sent on wire, 3734 * we add to pkt_len the headers size of all segments 3735 */ 3736 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3737 u16 gso_segs = shinfo->gso_segs; 3738 unsigned int hdr_len; 3739 3740 /* mac layer + network layer */ 3741 hdr_len = skb_transport_offset(skb); 3742 3743 /* + transport layer */ 3744 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3745 const struct tcphdr *th; 3746 struct tcphdr _tcphdr; 3747 3748 th = skb_header_pointer(skb, hdr_len, 3749 sizeof(_tcphdr), &_tcphdr); 3750 if (likely(th)) 3751 hdr_len += __tcp_hdrlen(th); 3752 } else { 3753 struct udphdr _udphdr; 3754 3755 if (skb_header_pointer(skb, hdr_len, 3756 sizeof(_udphdr), &_udphdr)) 3757 hdr_len += sizeof(struct udphdr); 3758 } 3759 3760 if (shinfo->gso_type & SKB_GSO_DODGY) 3761 gso_segs = DIV_ROUND_UP(skb->len - hdr_len, 3762 shinfo->gso_size); 3763 3764 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3765 } 3766 } 3767 3768 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3769 struct sk_buff **to_free, 3770 struct netdev_queue *txq) 3771 { 3772 int rc; 3773 3774 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3775 if (rc == NET_XMIT_SUCCESS) 3776 trace_qdisc_enqueue(q, txq, skb); 3777 return rc; 3778 } 3779 3780 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3781 struct net_device *dev, 3782 struct netdev_queue *txq) 3783 { 3784 spinlock_t *root_lock = qdisc_lock(q); 3785 struct sk_buff *to_free = NULL; 3786 bool contended; 3787 int rc; 3788 3789 qdisc_calculate_pkt_len(skb, q); 3790 3791 tcf_set_drop_reason(skb, SKB_DROP_REASON_QDISC_DROP); 3792 3793 if (q->flags & TCQ_F_NOLOCK) { 3794 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3795 qdisc_run_begin(q)) { 3796 /* Retest nolock_qdisc_is_empty() within the protection 3797 * of q->seqlock to protect from racing with requeuing. 3798 */ 3799 if (unlikely(!nolock_qdisc_is_empty(q))) { 3800 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3801 __qdisc_run(q); 3802 qdisc_run_end(q); 3803 3804 goto no_lock_out; 3805 } 3806 3807 qdisc_bstats_cpu_update(q, skb); 3808 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3809 !nolock_qdisc_is_empty(q)) 3810 __qdisc_run(q); 3811 3812 qdisc_run_end(q); 3813 return NET_XMIT_SUCCESS; 3814 } 3815 3816 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3817 qdisc_run(q); 3818 3819 no_lock_out: 3820 if (unlikely(to_free)) 3821 kfree_skb_list_reason(to_free, 3822 tcf_get_drop_reason(to_free)); 3823 return rc; 3824 } 3825 3826 if (unlikely(READ_ONCE(q->owner) == smp_processor_id())) { 3827 kfree_skb_reason(skb, SKB_DROP_REASON_TC_RECLASSIFY_LOOP); 3828 return NET_XMIT_DROP; 3829 } 3830 /* 3831 * Heuristic to force contended enqueues to serialize on a 3832 * separate lock before trying to get qdisc main lock. 3833 * This permits qdisc->running owner to get the lock more 3834 * often and dequeue packets faster. 3835 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 3836 * and then other tasks will only enqueue packets. The packets will be 3837 * sent after the qdisc owner is scheduled again. To prevent this 3838 * scenario the task always serialize on the lock. 3839 */ 3840 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 3841 if (unlikely(contended)) 3842 spin_lock(&q->busylock); 3843 3844 spin_lock(root_lock); 3845 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3846 __qdisc_drop(skb, &to_free); 3847 rc = NET_XMIT_DROP; 3848 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3849 qdisc_run_begin(q)) { 3850 /* 3851 * This is a work-conserving queue; there are no old skbs 3852 * waiting to be sent out; and the qdisc is not running - 3853 * xmit the skb directly. 3854 */ 3855 3856 qdisc_bstats_update(q, skb); 3857 3858 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3859 if (unlikely(contended)) { 3860 spin_unlock(&q->busylock); 3861 contended = false; 3862 } 3863 __qdisc_run(q); 3864 } 3865 3866 qdisc_run_end(q); 3867 rc = NET_XMIT_SUCCESS; 3868 } else { 3869 WRITE_ONCE(q->owner, smp_processor_id()); 3870 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3871 WRITE_ONCE(q->owner, -1); 3872 if (qdisc_run_begin(q)) { 3873 if (unlikely(contended)) { 3874 spin_unlock(&q->busylock); 3875 contended = false; 3876 } 3877 __qdisc_run(q); 3878 qdisc_run_end(q); 3879 } 3880 } 3881 spin_unlock(root_lock); 3882 if (unlikely(to_free)) 3883 kfree_skb_list_reason(to_free, 3884 tcf_get_drop_reason(to_free)); 3885 if (unlikely(contended)) 3886 spin_unlock(&q->busylock); 3887 return rc; 3888 } 3889 3890 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3891 static void skb_update_prio(struct sk_buff *skb) 3892 { 3893 const struct netprio_map *map; 3894 const struct sock *sk; 3895 unsigned int prioidx; 3896 3897 if (skb->priority) 3898 return; 3899 map = rcu_dereference_bh(skb->dev->priomap); 3900 if (!map) 3901 return; 3902 sk = skb_to_full_sk(skb); 3903 if (!sk) 3904 return; 3905 3906 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3907 3908 if (prioidx < map->priomap_len) 3909 skb->priority = map->priomap[prioidx]; 3910 } 3911 #else 3912 #define skb_update_prio(skb) 3913 #endif 3914 3915 /** 3916 * dev_loopback_xmit - loop back @skb 3917 * @net: network namespace this loopback is happening in 3918 * @sk: sk needed to be a netfilter okfn 3919 * @skb: buffer to transmit 3920 */ 3921 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3922 { 3923 skb_reset_mac_header(skb); 3924 __skb_pull(skb, skb_network_offset(skb)); 3925 skb->pkt_type = PACKET_LOOPBACK; 3926 if (skb->ip_summed == CHECKSUM_NONE) 3927 skb->ip_summed = CHECKSUM_UNNECESSARY; 3928 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 3929 skb_dst_force(skb); 3930 netif_rx(skb); 3931 return 0; 3932 } 3933 EXPORT_SYMBOL(dev_loopback_xmit); 3934 3935 #ifdef CONFIG_NET_EGRESS 3936 static struct netdev_queue * 3937 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 3938 { 3939 int qm = skb_get_queue_mapping(skb); 3940 3941 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 3942 } 3943 3944 static bool netdev_xmit_txqueue_skipped(void) 3945 { 3946 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 3947 } 3948 3949 void netdev_xmit_skip_txqueue(bool skip) 3950 { 3951 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 3952 } 3953 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 3954 #endif /* CONFIG_NET_EGRESS */ 3955 3956 #ifdef CONFIG_NET_XGRESS 3957 static int tc_run(struct tcx_entry *entry, struct sk_buff *skb, 3958 enum skb_drop_reason *drop_reason) 3959 { 3960 int ret = TC_ACT_UNSPEC; 3961 #ifdef CONFIG_NET_CLS_ACT 3962 struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq); 3963 struct tcf_result res; 3964 3965 if (!miniq) 3966 return ret; 3967 3968 if (static_branch_unlikely(&tcf_bypass_check_needed_key)) { 3969 if (tcf_block_bypass_sw(miniq->block)) 3970 return ret; 3971 } 3972 3973 tc_skb_cb(skb)->mru = 0; 3974 tc_skb_cb(skb)->post_ct = false; 3975 tcf_set_drop_reason(skb, *drop_reason); 3976 3977 mini_qdisc_bstats_cpu_update(miniq, skb); 3978 ret = tcf_classify(skb, miniq->block, miniq->filter_list, &res, false); 3979 /* Only tcf related quirks below. */ 3980 switch (ret) { 3981 case TC_ACT_SHOT: 3982 *drop_reason = tcf_get_drop_reason(skb); 3983 mini_qdisc_qstats_cpu_drop(miniq); 3984 break; 3985 case TC_ACT_OK: 3986 case TC_ACT_RECLASSIFY: 3987 skb->tc_index = TC_H_MIN(res.classid); 3988 break; 3989 } 3990 #endif /* CONFIG_NET_CLS_ACT */ 3991 return ret; 3992 } 3993 3994 static DEFINE_STATIC_KEY_FALSE(tcx_needed_key); 3995 3996 void tcx_inc(void) 3997 { 3998 static_branch_inc(&tcx_needed_key); 3999 } 4000 4001 void tcx_dec(void) 4002 { 4003 static_branch_dec(&tcx_needed_key); 4004 } 4005 4006 static __always_inline enum tcx_action_base 4007 tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb, 4008 const bool needs_mac) 4009 { 4010 const struct bpf_mprog_fp *fp; 4011 const struct bpf_prog *prog; 4012 int ret = TCX_NEXT; 4013 4014 if (needs_mac) 4015 __skb_push(skb, skb->mac_len); 4016 bpf_mprog_foreach_prog(entry, fp, prog) { 4017 bpf_compute_data_pointers(skb); 4018 ret = bpf_prog_run(prog, skb); 4019 if (ret != TCX_NEXT) 4020 break; 4021 } 4022 if (needs_mac) 4023 __skb_pull(skb, skb->mac_len); 4024 return tcx_action_code(skb, ret); 4025 } 4026 4027 static __always_inline struct sk_buff * 4028 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4029 struct net_device *orig_dev, bool *another) 4030 { 4031 struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress); 4032 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_INGRESS; 4033 int sch_ret; 4034 4035 if (!entry) 4036 return skb; 4037 if (*pt_prev) { 4038 *ret = deliver_skb(skb, *pt_prev, orig_dev); 4039 *pt_prev = NULL; 4040 } 4041 4042 qdisc_skb_cb(skb)->pkt_len = skb->len; 4043 tcx_set_ingress(skb, true); 4044 4045 if (static_branch_unlikely(&tcx_needed_key)) { 4046 sch_ret = tcx_run(entry, skb, true); 4047 if (sch_ret != TC_ACT_UNSPEC) 4048 goto ingress_verdict; 4049 } 4050 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4051 ingress_verdict: 4052 switch (sch_ret) { 4053 case TC_ACT_REDIRECT: 4054 /* skb_mac_header check was done by BPF, so we can safely 4055 * push the L2 header back before redirecting to another 4056 * netdev. 4057 */ 4058 __skb_push(skb, skb->mac_len); 4059 if (skb_do_redirect(skb) == -EAGAIN) { 4060 __skb_pull(skb, skb->mac_len); 4061 *another = true; 4062 break; 4063 } 4064 *ret = NET_RX_SUCCESS; 4065 return NULL; 4066 case TC_ACT_SHOT: 4067 kfree_skb_reason(skb, drop_reason); 4068 *ret = NET_RX_DROP; 4069 return NULL; 4070 /* used by tc_run */ 4071 case TC_ACT_STOLEN: 4072 case TC_ACT_QUEUED: 4073 case TC_ACT_TRAP: 4074 consume_skb(skb); 4075 fallthrough; 4076 case TC_ACT_CONSUMED: 4077 *ret = NET_RX_SUCCESS; 4078 return NULL; 4079 } 4080 4081 return skb; 4082 } 4083 4084 static __always_inline struct sk_buff * 4085 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4086 { 4087 struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress); 4088 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_EGRESS; 4089 int sch_ret; 4090 4091 if (!entry) 4092 return skb; 4093 4094 /* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was 4095 * already set by the caller. 4096 */ 4097 if (static_branch_unlikely(&tcx_needed_key)) { 4098 sch_ret = tcx_run(entry, skb, false); 4099 if (sch_ret != TC_ACT_UNSPEC) 4100 goto egress_verdict; 4101 } 4102 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4103 egress_verdict: 4104 switch (sch_ret) { 4105 case TC_ACT_REDIRECT: 4106 /* No need to push/pop skb's mac_header here on egress! */ 4107 skb_do_redirect(skb); 4108 *ret = NET_XMIT_SUCCESS; 4109 return NULL; 4110 case TC_ACT_SHOT: 4111 kfree_skb_reason(skb, drop_reason); 4112 *ret = NET_XMIT_DROP; 4113 return NULL; 4114 /* used by tc_run */ 4115 case TC_ACT_STOLEN: 4116 case TC_ACT_QUEUED: 4117 case TC_ACT_TRAP: 4118 consume_skb(skb); 4119 fallthrough; 4120 case TC_ACT_CONSUMED: 4121 *ret = NET_XMIT_SUCCESS; 4122 return NULL; 4123 } 4124 4125 return skb; 4126 } 4127 #else 4128 static __always_inline struct sk_buff * 4129 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4130 struct net_device *orig_dev, bool *another) 4131 { 4132 return skb; 4133 } 4134 4135 static __always_inline struct sk_buff * 4136 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4137 { 4138 return skb; 4139 } 4140 #endif /* CONFIG_NET_XGRESS */ 4141 4142 #ifdef CONFIG_XPS 4143 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4144 struct xps_dev_maps *dev_maps, unsigned int tci) 4145 { 4146 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4147 struct xps_map *map; 4148 int queue_index = -1; 4149 4150 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4151 return queue_index; 4152 4153 tci *= dev_maps->num_tc; 4154 tci += tc; 4155 4156 map = rcu_dereference(dev_maps->attr_map[tci]); 4157 if (map) { 4158 if (map->len == 1) 4159 queue_index = map->queues[0]; 4160 else 4161 queue_index = map->queues[reciprocal_scale( 4162 skb_get_hash(skb), map->len)]; 4163 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4164 queue_index = -1; 4165 } 4166 return queue_index; 4167 } 4168 #endif 4169 4170 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4171 struct sk_buff *skb) 4172 { 4173 #ifdef CONFIG_XPS 4174 struct xps_dev_maps *dev_maps; 4175 struct sock *sk = skb->sk; 4176 int queue_index = -1; 4177 4178 if (!static_key_false(&xps_needed)) 4179 return -1; 4180 4181 rcu_read_lock(); 4182 if (!static_key_false(&xps_rxqs_needed)) 4183 goto get_cpus_map; 4184 4185 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4186 if (dev_maps) { 4187 int tci = sk_rx_queue_get(sk); 4188 4189 if (tci >= 0) 4190 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4191 tci); 4192 } 4193 4194 get_cpus_map: 4195 if (queue_index < 0) { 4196 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4197 if (dev_maps) { 4198 unsigned int tci = skb->sender_cpu - 1; 4199 4200 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4201 tci); 4202 } 4203 } 4204 rcu_read_unlock(); 4205 4206 return queue_index; 4207 #else 4208 return -1; 4209 #endif 4210 } 4211 4212 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4213 struct net_device *sb_dev) 4214 { 4215 return 0; 4216 } 4217 EXPORT_SYMBOL(dev_pick_tx_zero); 4218 4219 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 4220 struct net_device *sb_dev) 4221 { 4222 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 4223 } 4224 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 4225 4226 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4227 struct net_device *sb_dev) 4228 { 4229 struct sock *sk = skb->sk; 4230 int queue_index = sk_tx_queue_get(sk); 4231 4232 sb_dev = sb_dev ? : dev; 4233 4234 if (queue_index < 0 || skb->ooo_okay || 4235 queue_index >= dev->real_num_tx_queues) { 4236 int new_index = get_xps_queue(dev, sb_dev, skb); 4237 4238 if (new_index < 0) 4239 new_index = skb_tx_hash(dev, sb_dev, skb); 4240 4241 if (queue_index != new_index && sk && 4242 sk_fullsock(sk) && 4243 rcu_access_pointer(sk->sk_dst_cache)) 4244 sk_tx_queue_set(sk, new_index); 4245 4246 queue_index = new_index; 4247 } 4248 4249 return queue_index; 4250 } 4251 EXPORT_SYMBOL(netdev_pick_tx); 4252 4253 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4254 struct sk_buff *skb, 4255 struct net_device *sb_dev) 4256 { 4257 int queue_index = 0; 4258 4259 #ifdef CONFIG_XPS 4260 u32 sender_cpu = skb->sender_cpu - 1; 4261 4262 if (sender_cpu >= (u32)NR_CPUS) 4263 skb->sender_cpu = raw_smp_processor_id() + 1; 4264 #endif 4265 4266 if (dev->real_num_tx_queues != 1) { 4267 const struct net_device_ops *ops = dev->netdev_ops; 4268 4269 if (ops->ndo_select_queue) 4270 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4271 else 4272 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4273 4274 queue_index = netdev_cap_txqueue(dev, queue_index); 4275 } 4276 4277 skb_set_queue_mapping(skb, queue_index); 4278 return netdev_get_tx_queue(dev, queue_index); 4279 } 4280 4281 /** 4282 * __dev_queue_xmit() - transmit a buffer 4283 * @skb: buffer to transmit 4284 * @sb_dev: suboordinate device used for L2 forwarding offload 4285 * 4286 * Queue a buffer for transmission to a network device. The caller must 4287 * have set the device and priority and built the buffer before calling 4288 * this function. The function can be called from an interrupt. 4289 * 4290 * When calling this method, interrupts MUST be enabled. This is because 4291 * the BH enable code must have IRQs enabled so that it will not deadlock. 4292 * 4293 * Regardless of the return value, the skb is consumed, so it is currently 4294 * difficult to retry a send to this method. (You can bump the ref count 4295 * before sending to hold a reference for retry if you are careful.) 4296 * 4297 * Return: 4298 * * 0 - buffer successfully transmitted 4299 * * positive qdisc return code - NET_XMIT_DROP etc. 4300 * * negative errno - other errors 4301 */ 4302 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4303 { 4304 struct net_device *dev = skb->dev; 4305 struct netdev_queue *txq = NULL; 4306 struct Qdisc *q; 4307 int rc = -ENOMEM; 4308 bool again = false; 4309 4310 skb_reset_mac_header(skb); 4311 skb_assert_len(skb); 4312 4313 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4314 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4315 4316 /* Disable soft irqs for various locks below. Also 4317 * stops preemption for RCU. 4318 */ 4319 rcu_read_lock_bh(); 4320 4321 skb_update_prio(skb); 4322 4323 qdisc_pkt_len_init(skb); 4324 tcx_set_ingress(skb, false); 4325 #ifdef CONFIG_NET_EGRESS 4326 if (static_branch_unlikely(&egress_needed_key)) { 4327 if (nf_hook_egress_active()) { 4328 skb = nf_hook_egress(skb, &rc, dev); 4329 if (!skb) 4330 goto out; 4331 } 4332 4333 netdev_xmit_skip_txqueue(false); 4334 4335 nf_skip_egress(skb, true); 4336 skb = sch_handle_egress(skb, &rc, dev); 4337 if (!skb) 4338 goto out; 4339 nf_skip_egress(skb, false); 4340 4341 if (netdev_xmit_txqueue_skipped()) 4342 txq = netdev_tx_queue_mapping(dev, skb); 4343 } 4344 #endif 4345 /* If device/qdisc don't need skb->dst, release it right now while 4346 * its hot in this cpu cache. 4347 */ 4348 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4349 skb_dst_drop(skb); 4350 else 4351 skb_dst_force(skb); 4352 4353 if (!txq) 4354 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4355 4356 q = rcu_dereference_bh(txq->qdisc); 4357 4358 trace_net_dev_queue(skb); 4359 if (q->enqueue) { 4360 rc = __dev_xmit_skb(skb, q, dev, txq); 4361 goto out; 4362 } 4363 4364 /* The device has no queue. Common case for software devices: 4365 * loopback, all the sorts of tunnels... 4366 4367 * Really, it is unlikely that netif_tx_lock protection is necessary 4368 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4369 * counters.) 4370 * However, it is possible, that they rely on protection 4371 * made by us here. 4372 4373 * Check this and shot the lock. It is not prone from deadlocks. 4374 *Either shot noqueue qdisc, it is even simpler 8) 4375 */ 4376 if (dev->flags & IFF_UP) { 4377 int cpu = smp_processor_id(); /* ok because BHs are off */ 4378 4379 /* Other cpus might concurrently change txq->xmit_lock_owner 4380 * to -1 or to their cpu id, but not to our id. 4381 */ 4382 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4383 if (dev_xmit_recursion()) 4384 goto recursion_alert; 4385 4386 skb = validate_xmit_skb(skb, dev, &again); 4387 if (!skb) 4388 goto out; 4389 4390 HARD_TX_LOCK(dev, txq, cpu); 4391 4392 if (!netif_xmit_stopped(txq)) { 4393 dev_xmit_recursion_inc(); 4394 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4395 dev_xmit_recursion_dec(); 4396 if (dev_xmit_complete(rc)) { 4397 HARD_TX_UNLOCK(dev, txq); 4398 goto out; 4399 } 4400 } 4401 HARD_TX_UNLOCK(dev, txq); 4402 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4403 dev->name); 4404 } else { 4405 /* Recursion is detected! It is possible, 4406 * unfortunately 4407 */ 4408 recursion_alert: 4409 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4410 dev->name); 4411 } 4412 } 4413 4414 rc = -ENETDOWN; 4415 rcu_read_unlock_bh(); 4416 4417 dev_core_stats_tx_dropped_inc(dev); 4418 kfree_skb_list(skb); 4419 return rc; 4420 out: 4421 rcu_read_unlock_bh(); 4422 return rc; 4423 } 4424 EXPORT_SYMBOL(__dev_queue_xmit); 4425 4426 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4427 { 4428 struct net_device *dev = skb->dev; 4429 struct sk_buff *orig_skb = skb; 4430 struct netdev_queue *txq; 4431 int ret = NETDEV_TX_BUSY; 4432 bool again = false; 4433 4434 if (unlikely(!netif_running(dev) || 4435 !netif_carrier_ok(dev))) 4436 goto drop; 4437 4438 skb = validate_xmit_skb_list(skb, dev, &again); 4439 if (skb != orig_skb) 4440 goto drop; 4441 4442 skb_set_queue_mapping(skb, queue_id); 4443 txq = skb_get_tx_queue(dev, skb); 4444 4445 local_bh_disable(); 4446 4447 dev_xmit_recursion_inc(); 4448 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4449 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4450 ret = netdev_start_xmit(skb, dev, txq, false); 4451 HARD_TX_UNLOCK(dev, txq); 4452 dev_xmit_recursion_dec(); 4453 4454 local_bh_enable(); 4455 return ret; 4456 drop: 4457 dev_core_stats_tx_dropped_inc(dev); 4458 kfree_skb_list(skb); 4459 return NET_XMIT_DROP; 4460 } 4461 EXPORT_SYMBOL(__dev_direct_xmit); 4462 4463 /************************************************************************* 4464 * Receiver routines 4465 *************************************************************************/ 4466 static DEFINE_PER_CPU(struct task_struct *, backlog_napi); 4467 4468 int weight_p __read_mostly = 64; /* old backlog weight */ 4469 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4470 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4471 4472 /* Called with irq disabled */ 4473 static inline void ____napi_schedule(struct softnet_data *sd, 4474 struct napi_struct *napi) 4475 { 4476 struct task_struct *thread; 4477 4478 lockdep_assert_irqs_disabled(); 4479 4480 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4481 /* Paired with smp_mb__before_atomic() in 4482 * napi_enable()/dev_set_threaded(). 4483 * Use READ_ONCE() to guarantee a complete 4484 * read on napi->thread. Only call 4485 * wake_up_process() when it's not NULL. 4486 */ 4487 thread = READ_ONCE(napi->thread); 4488 if (thread) { 4489 if (use_backlog_threads() && thread == raw_cpu_read(backlog_napi)) 4490 goto use_local_napi; 4491 4492 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4493 wake_up_process(thread); 4494 return; 4495 } 4496 } 4497 4498 use_local_napi: 4499 list_add_tail(&napi->poll_list, &sd->poll_list); 4500 WRITE_ONCE(napi->list_owner, smp_processor_id()); 4501 /* If not called from net_rx_action() 4502 * we have to raise NET_RX_SOFTIRQ. 4503 */ 4504 if (!sd->in_net_rx_action) 4505 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4506 } 4507 4508 #ifdef CONFIG_RPS 4509 4510 struct static_key_false rps_needed __read_mostly; 4511 EXPORT_SYMBOL(rps_needed); 4512 struct static_key_false rfs_needed __read_mostly; 4513 EXPORT_SYMBOL(rfs_needed); 4514 4515 static struct rps_dev_flow * 4516 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4517 struct rps_dev_flow *rflow, u16 next_cpu) 4518 { 4519 if (next_cpu < nr_cpu_ids) { 4520 #ifdef CONFIG_RFS_ACCEL 4521 struct netdev_rx_queue *rxqueue; 4522 struct rps_dev_flow_table *flow_table; 4523 struct rps_dev_flow *old_rflow; 4524 u32 flow_id, head; 4525 u16 rxq_index; 4526 int rc; 4527 4528 /* Should we steer this flow to a different hardware queue? */ 4529 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4530 !(dev->features & NETIF_F_NTUPLE)) 4531 goto out; 4532 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4533 if (rxq_index == skb_get_rx_queue(skb)) 4534 goto out; 4535 4536 rxqueue = dev->_rx + rxq_index; 4537 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4538 if (!flow_table) 4539 goto out; 4540 flow_id = skb_get_hash(skb) & flow_table->mask; 4541 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4542 rxq_index, flow_id); 4543 if (rc < 0) 4544 goto out; 4545 old_rflow = rflow; 4546 rflow = &flow_table->flows[flow_id]; 4547 WRITE_ONCE(rflow->filter, rc); 4548 if (old_rflow->filter == rc) 4549 WRITE_ONCE(old_rflow->filter, RPS_NO_FILTER); 4550 out: 4551 #endif 4552 head = READ_ONCE(per_cpu(softnet_data, next_cpu).input_queue_head); 4553 rps_input_queue_tail_save(&rflow->last_qtail, head); 4554 } 4555 4556 WRITE_ONCE(rflow->cpu, next_cpu); 4557 return rflow; 4558 } 4559 4560 /* 4561 * get_rps_cpu is called from netif_receive_skb and returns the target 4562 * CPU from the RPS map of the receiving queue for a given skb. 4563 * rcu_read_lock must be held on entry. 4564 */ 4565 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4566 struct rps_dev_flow **rflowp) 4567 { 4568 const struct rps_sock_flow_table *sock_flow_table; 4569 struct netdev_rx_queue *rxqueue = dev->_rx; 4570 struct rps_dev_flow_table *flow_table; 4571 struct rps_map *map; 4572 int cpu = -1; 4573 u32 tcpu; 4574 u32 hash; 4575 4576 if (skb_rx_queue_recorded(skb)) { 4577 u16 index = skb_get_rx_queue(skb); 4578 4579 if (unlikely(index >= dev->real_num_rx_queues)) { 4580 WARN_ONCE(dev->real_num_rx_queues > 1, 4581 "%s received packet on queue %u, but number " 4582 "of RX queues is %u\n", 4583 dev->name, index, dev->real_num_rx_queues); 4584 goto done; 4585 } 4586 rxqueue += index; 4587 } 4588 4589 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4590 4591 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4592 map = rcu_dereference(rxqueue->rps_map); 4593 if (!flow_table && !map) 4594 goto done; 4595 4596 skb_reset_network_header(skb); 4597 hash = skb_get_hash(skb); 4598 if (!hash) 4599 goto done; 4600 4601 sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table); 4602 if (flow_table && sock_flow_table) { 4603 struct rps_dev_flow *rflow; 4604 u32 next_cpu; 4605 u32 ident; 4606 4607 /* First check into global flow table if there is a match. 4608 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow(). 4609 */ 4610 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]); 4611 if ((ident ^ hash) & ~net_hotdata.rps_cpu_mask) 4612 goto try_rps; 4613 4614 next_cpu = ident & net_hotdata.rps_cpu_mask; 4615 4616 /* OK, now we know there is a match, 4617 * we can look at the local (per receive queue) flow table 4618 */ 4619 rflow = &flow_table->flows[hash & flow_table->mask]; 4620 tcpu = rflow->cpu; 4621 4622 /* 4623 * If the desired CPU (where last recvmsg was done) is 4624 * different from current CPU (one in the rx-queue flow 4625 * table entry), switch if one of the following holds: 4626 * - Current CPU is unset (>= nr_cpu_ids). 4627 * - Current CPU is offline. 4628 * - The current CPU's queue tail has advanced beyond the 4629 * last packet that was enqueued using this table entry. 4630 * This guarantees that all previous packets for the flow 4631 * have been dequeued, thus preserving in order delivery. 4632 */ 4633 if (unlikely(tcpu != next_cpu) && 4634 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4635 ((int)(READ_ONCE(per_cpu(softnet_data, tcpu).input_queue_head) - 4636 rflow->last_qtail)) >= 0)) { 4637 tcpu = next_cpu; 4638 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4639 } 4640 4641 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4642 *rflowp = rflow; 4643 cpu = tcpu; 4644 goto done; 4645 } 4646 } 4647 4648 try_rps: 4649 4650 if (map) { 4651 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4652 if (cpu_online(tcpu)) { 4653 cpu = tcpu; 4654 goto done; 4655 } 4656 } 4657 4658 done: 4659 return cpu; 4660 } 4661 4662 #ifdef CONFIG_RFS_ACCEL 4663 4664 /** 4665 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4666 * @dev: Device on which the filter was set 4667 * @rxq_index: RX queue index 4668 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4669 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4670 * 4671 * Drivers that implement ndo_rx_flow_steer() should periodically call 4672 * this function for each installed filter and remove the filters for 4673 * which it returns %true. 4674 */ 4675 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4676 u32 flow_id, u16 filter_id) 4677 { 4678 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4679 struct rps_dev_flow_table *flow_table; 4680 struct rps_dev_flow *rflow; 4681 bool expire = true; 4682 unsigned int cpu; 4683 4684 rcu_read_lock(); 4685 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4686 if (flow_table && flow_id <= flow_table->mask) { 4687 rflow = &flow_table->flows[flow_id]; 4688 cpu = READ_ONCE(rflow->cpu); 4689 if (READ_ONCE(rflow->filter) == filter_id && cpu < nr_cpu_ids && 4690 ((int)(READ_ONCE(per_cpu(softnet_data, cpu).input_queue_head) - 4691 READ_ONCE(rflow->last_qtail)) < 4692 (int)(10 * flow_table->mask))) 4693 expire = false; 4694 } 4695 rcu_read_unlock(); 4696 return expire; 4697 } 4698 EXPORT_SYMBOL(rps_may_expire_flow); 4699 4700 #endif /* CONFIG_RFS_ACCEL */ 4701 4702 /* Called from hardirq (IPI) context */ 4703 static void rps_trigger_softirq(void *data) 4704 { 4705 struct softnet_data *sd = data; 4706 4707 ____napi_schedule(sd, &sd->backlog); 4708 sd->received_rps++; 4709 } 4710 4711 #endif /* CONFIG_RPS */ 4712 4713 /* Called from hardirq (IPI) context */ 4714 static void trigger_rx_softirq(void *data) 4715 { 4716 struct softnet_data *sd = data; 4717 4718 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4719 smp_store_release(&sd->defer_ipi_scheduled, 0); 4720 } 4721 4722 /* 4723 * After we queued a packet into sd->input_pkt_queue, 4724 * we need to make sure this queue is serviced soon. 4725 * 4726 * - If this is another cpu queue, link it to our rps_ipi_list, 4727 * and make sure we will process rps_ipi_list from net_rx_action(). 4728 * 4729 * - If this is our own queue, NAPI schedule our backlog. 4730 * Note that this also raises NET_RX_SOFTIRQ. 4731 */ 4732 static void napi_schedule_rps(struct softnet_data *sd) 4733 { 4734 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4735 4736 #ifdef CONFIG_RPS 4737 if (sd != mysd) { 4738 if (use_backlog_threads()) { 4739 __napi_schedule_irqoff(&sd->backlog); 4740 return; 4741 } 4742 4743 sd->rps_ipi_next = mysd->rps_ipi_list; 4744 mysd->rps_ipi_list = sd; 4745 4746 /* If not called from net_rx_action() or napi_threaded_poll() 4747 * we have to raise NET_RX_SOFTIRQ. 4748 */ 4749 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll) 4750 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4751 return; 4752 } 4753 #endif /* CONFIG_RPS */ 4754 __napi_schedule_irqoff(&mysd->backlog); 4755 } 4756 4757 void kick_defer_list_purge(struct softnet_data *sd, unsigned int cpu) 4758 { 4759 unsigned long flags; 4760 4761 if (use_backlog_threads()) { 4762 backlog_lock_irq_save(sd, &flags); 4763 4764 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 4765 __napi_schedule_irqoff(&sd->backlog); 4766 4767 backlog_unlock_irq_restore(sd, &flags); 4768 4769 } else if (!cmpxchg(&sd->defer_ipi_scheduled, 0, 1)) { 4770 smp_call_function_single_async(cpu, &sd->defer_csd); 4771 } 4772 } 4773 4774 #ifdef CONFIG_NET_FLOW_LIMIT 4775 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4776 #endif 4777 4778 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4779 { 4780 #ifdef CONFIG_NET_FLOW_LIMIT 4781 struct sd_flow_limit *fl; 4782 struct softnet_data *sd; 4783 unsigned int old_flow, new_flow; 4784 4785 if (qlen < (READ_ONCE(net_hotdata.max_backlog) >> 1)) 4786 return false; 4787 4788 sd = this_cpu_ptr(&softnet_data); 4789 4790 rcu_read_lock(); 4791 fl = rcu_dereference(sd->flow_limit); 4792 if (fl) { 4793 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4794 old_flow = fl->history[fl->history_head]; 4795 fl->history[fl->history_head] = new_flow; 4796 4797 fl->history_head++; 4798 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4799 4800 if (likely(fl->buckets[old_flow])) 4801 fl->buckets[old_flow]--; 4802 4803 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4804 fl->count++; 4805 rcu_read_unlock(); 4806 return true; 4807 } 4808 } 4809 rcu_read_unlock(); 4810 #endif 4811 return false; 4812 } 4813 4814 /* 4815 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4816 * queue (may be a remote CPU queue). 4817 */ 4818 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4819 unsigned int *qtail) 4820 { 4821 enum skb_drop_reason reason; 4822 struct softnet_data *sd; 4823 unsigned long flags; 4824 unsigned int qlen; 4825 int max_backlog; 4826 u32 tail; 4827 4828 reason = SKB_DROP_REASON_DEV_READY; 4829 if (!netif_running(skb->dev)) 4830 goto bad_dev; 4831 4832 reason = SKB_DROP_REASON_CPU_BACKLOG; 4833 sd = &per_cpu(softnet_data, cpu); 4834 4835 qlen = skb_queue_len_lockless(&sd->input_pkt_queue); 4836 max_backlog = READ_ONCE(net_hotdata.max_backlog); 4837 if (unlikely(qlen > max_backlog)) 4838 goto cpu_backlog_drop; 4839 backlog_lock_irq_save(sd, &flags); 4840 qlen = skb_queue_len(&sd->input_pkt_queue); 4841 if (qlen <= max_backlog && !skb_flow_limit(skb, qlen)) { 4842 if (!qlen) { 4843 /* Schedule NAPI for backlog device. We can use 4844 * non atomic operation as we own the queue lock. 4845 */ 4846 if (!__test_and_set_bit(NAPI_STATE_SCHED, 4847 &sd->backlog.state)) 4848 napi_schedule_rps(sd); 4849 } 4850 __skb_queue_tail(&sd->input_pkt_queue, skb); 4851 tail = rps_input_queue_tail_incr(sd); 4852 backlog_unlock_irq_restore(sd, &flags); 4853 4854 /* save the tail outside of the critical section */ 4855 rps_input_queue_tail_save(qtail, tail); 4856 return NET_RX_SUCCESS; 4857 } 4858 4859 backlog_unlock_irq_restore(sd, &flags); 4860 4861 cpu_backlog_drop: 4862 atomic_inc(&sd->dropped); 4863 bad_dev: 4864 dev_core_stats_rx_dropped_inc(skb->dev); 4865 kfree_skb_reason(skb, reason); 4866 return NET_RX_DROP; 4867 } 4868 4869 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4870 { 4871 struct net_device *dev = skb->dev; 4872 struct netdev_rx_queue *rxqueue; 4873 4874 rxqueue = dev->_rx; 4875 4876 if (skb_rx_queue_recorded(skb)) { 4877 u16 index = skb_get_rx_queue(skb); 4878 4879 if (unlikely(index >= dev->real_num_rx_queues)) { 4880 WARN_ONCE(dev->real_num_rx_queues > 1, 4881 "%s received packet on queue %u, but number " 4882 "of RX queues is %u\n", 4883 dev->name, index, dev->real_num_rx_queues); 4884 4885 return rxqueue; /* Return first rxqueue */ 4886 } 4887 rxqueue += index; 4888 } 4889 return rxqueue; 4890 } 4891 4892 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4893 struct bpf_prog *xdp_prog) 4894 { 4895 void *orig_data, *orig_data_end, *hard_start; 4896 struct netdev_rx_queue *rxqueue; 4897 bool orig_bcast, orig_host; 4898 u32 mac_len, frame_sz; 4899 __be16 orig_eth_type; 4900 struct ethhdr *eth; 4901 u32 metalen, act; 4902 int off; 4903 4904 /* The XDP program wants to see the packet starting at the MAC 4905 * header. 4906 */ 4907 mac_len = skb->data - skb_mac_header(skb); 4908 hard_start = skb->data - skb_headroom(skb); 4909 4910 /* SKB "head" area always have tailroom for skb_shared_info */ 4911 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4912 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4913 4914 rxqueue = netif_get_rxqueue(skb); 4915 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4916 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4917 skb_headlen(skb) + mac_len, true); 4918 if (skb_is_nonlinear(skb)) { 4919 skb_shinfo(skb)->xdp_frags_size = skb->data_len; 4920 xdp_buff_set_frags_flag(xdp); 4921 } else { 4922 xdp_buff_clear_frags_flag(xdp); 4923 } 4924 4925 orig_data_end = xdp->data_end; 4926 orig_data = xdp->data; 4927 eth = (struct ethhdr *)xdp->data; 4928 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4929 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4930 orig_eth_type = eth->h_proto; 4931 4932 act = bpf_prog_run_xdp(xdp_prog, xdp); 4933 4934 /* check if bpf_xdp_adjust_head was used */ 4935 off = xdp->data - orig_data; 4936 if (off) { 4937 if (off > 0) 4938 __skb_pull(skb, off); 4939 else if (off < 0) 4940 __skb_push(skb, -off); 4941 4942 skb->mac_header += off; 4943 skb_reset_network_header(skb); 4944 } 4945 4946 /* check if bpf_xdp_adjust_tail was used */ 4947 off = xdp->data_end - orig_data_end; 4948 if (off != 0) { 4949 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4950 skb->len += off; /* positive on grow, negative on shrink */ 4951 } 4952 4953 /* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers 4954 * (e.g. bpf_xdp_adjust_tail), we need to update data_len here. 4955 */ 4956 if (xdp_buff_has_frags(xdp)) 4957 skb->data_len = skb_shinfo(skb)->xdp_frags_size; 4958 else 4959 skb->data_len = 0; 4960 4961 /* check if XDP changed eth hdr such SKB needs update */ 4962 eth = (struct ethhdr *)xdp->data; 4963 if ((orig_eth_type != eth->h_proto) || 4964 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4965 skb->dev->dev_addr)) || 4966 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4967 __skb_push(skb, ETH_HLEN); 4968 skb->pkt_type = PACKET_HOST; 4969 skb->protocol = eth_type_trans(skb, skb->dev); 4970 } 4971 4972 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4973 * before calling us again on redirect path. We do not call do_redirect 4974 * as we leave that up to the caller. 4975 * 4976 * Caller is responsible for managing lifetime of skb (i.e. calling 4977 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4978 */ 4979 switch (act) { 4980 case XDP_REDIRECT: 4981 case XDP_TX: 4982 __skb_push(skb, mac_len); 4983 break; 4984 case XDP_PASS: 4985 metalen = xdp->data - xdp->data_meta; 4986 if (metalen) 4987 skb_metadata_set(skb, metalen); 4988 break; 4989 } 4990 4991 return act; 4992 } 4993 4994 static int 4995 netif_skb_check_for_xdp(struct sk_buff **pskb, struct bpf_prog *prog) 4996 { 4997 struct sk_buff *skb = *pskb; 4998 int err, hroom, troom; 4999 5000 if (!skb_cow_data_for_xdp(this_cpu_read(system_page_pool), pskb, prog)) 5001 return 0; 5002 5003 /* In case we have to go down the path and also linearize, 5004 * then lets do the pskb_expand_head() work just once here. 5005 */ 5006 hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 5007 troom = skb->tail + skb->data_len - skb->end; 5008 err = pskb_expand_head(skb, 5009 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 5010 troom > 0 ? troom + 128 : 0, GFP_ATOMIC); 5011 if (err) 5012 return err; 5013 5014 return skb_linearize(skb); 5015 } 5016 5017 static u32 netif_receive_generic_xdp(struct sk_buff **pskb, 5018 struct xdp_buff *xdp, 5019 struct bpf_prog *xdp_prog) 5020 { 5021 struct sk_buff *skb = *pskb; 5022 u32 mac_len, act = XDP_DROP; 5023 5024 /* Reinjected packets coming from act_mirred or similar should 5025 * not get XDP generic processing. 5026 */ 5027 if (skb_is_redirected(skb)) 5028 return XDP_PASS; 5029 5030 /* XDP packets must have sufficient headroom of XDP_PACKET_HEADROOM 5031 * bytes. This is the guarantee that also native XDP provides, 5032 * thus we need to do it here as well. 5033 */ 5034 mac_len = skb->data - skb_mac_header(skb); 5035 __skb_push(skb, mac_len); 5036 5037 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 5038 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 5039 if (netif_skb_check_for_xdp(pskb, xdp_prog)) 5040 goto do_drop; 5041 } 5042 5043 __skb_pull(*pskb, mac_len); 5044 5045 act = bpf_prog_run_generic_xdp(*pskb, xdp, xdp_prog); 5046 switch (act) { 5047 case XDP_REDIRECT: 5048 case XDP_TX: 5049 case XDP_PASS: 5050 break; 5051 default: 5052 bpf_warn_invalid_xdp_action((*pskb)->dev, xdp_prog, act); 5053 fallthrough; 5054 case XDP_ABORTED: 5055 trace_xdp_exception((*pskb)->dev, xdp_prog, act); 5056 fallthrough; 5057 case XDP_DROP: 5058 do_drop: 5059 kfree_skb(*pskb); 5060 break; 5061 } 5062 5063 return act; 5064 } 5065 5066 /* When doing generic XDP we have to bypass the qdisc layer and the 5067 * network taps in order to match in-driver-XDP behavior. This also means 5068 * that XDP packets are able to starve other packets going through a qdisc, 5069 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 5070 * queues, so they do not have this starvation issue. 5071 */ 5072 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 5073 { 5074 struct net_device *dev = skb->dev; 5075 struct netdev_queue *txq; 5076 bool free_skb = true; 5077 int cpu, rc; 5078 5079 txq = netdev_core_pick_tx(dev, skb, NULL); 5080 cpu = smp_processor_id(); 5081 HARD_TX_LOCK(dev, txq, cpu); 5082 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 5083 rc = netdev_start_xmit(skb, dev, txq, 0); 5084 if (dev_xmit_complete(rc)) 5085 free_skb = false; 5086 } 5087 HARD_TX_UNLOCK(dev, txq); 5088 if (free_skb) { 5089 trace_xdp_exception(dev, xdp_prog, XDP_TX); 5090 dev_core_stats_tx_dropped_inc(dev); 5091 kfree_skb(skb); 5092 } 5093 } 5094 5095 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 5096 5097 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff **pskb) 5098 { 5099 if (xdp_prog) { 5100 struct xdp_buff xdp; 5101 u32 act; 5102 int err; 5103 5104 act = netif_receive_generic_xdp(pskb, &xdp, xdp_prog); 5105 if (act != XDP_PASS) { 5106 switch (act) { 5107 case XDP_REDIRECT: 5108 err = xdp_do_generic_redirect((*pskb)->dev, *pskb, 5109 &xdp, xdp_prog); 5110 if (err) 5111 goto out_redir; 5112 break; 5113 case XDP_TX: 5114 generic_xdp_tx(*pskb, xdp_prog); 5115 break; 5116 } 5117 return XDP_DROP; 5118 } 5119 } 5120 return XDP_PASS; 5121 out_redir: 5122 kfree_skb_reason(*pskb, SKB_DROP_REASON_XDP); 5123 return XDP_DROP; 5124 } 5125 EXPORT_SYMBOL_GPL(do_xdp_generic); 5126 5127 static int netif_rx_internal(struct sk_buff *skb) 5128 { 5129 int ret; 5130 5131 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5132 5133 trace_netif_rx(skb); 5134 5135 #ifdef CONFIG_RPS 5136 if (static_branch_unlikely(&rps_needed)) { 5137 struct rps_dev_flow voidflow, *rflow = &voidflow; 5138 int cpu; 5139 5140 rcu_read_lock(); 5141 5142 cpu = get_rps_cpu(skb->dev, skb, &rflow); 5143 if (cpu < 0) 5144 cpu = smp_processor_id(); 5145 5146 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5147 5148 rcu_read_unlock(); 5149 } else 5150 #endif 5151 { 5152 unsigned int qtail; 5153 5154 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 5155 } 5156 return ret; 5157 } 5158 5159 /** 5160 * __netif_rx - Slightly optimized version of netif_rx 5161 * @skb: buffer to post 5162 * 5163 * This behaves as netif_rx except that it does not disable bottom halves. 5164 * As a result this function may only be invoked from the interrupt context 5165 * (either hard or soft interrupt). 5166 */ 5167 int __netif_rx(struct sk_buff *skb) 5168 { 5169 int ret; 5170 5171 lockdep_assert_once(hardirq_count() | softirq_count()); 5172 5173 trace_netif_rx_entry(skb); 5174 ret = netif_rx_internal(skb); 5175 trace_netif_rx_exit(ret); 5176 return ret; 5177 } 5178 EXPORT_SYMBOL(__netif_rx); 5179 5180 /** 5181 * netif_rx - post buffer to the network code 5182 * @skb: buffer to post 5183 * 5184 * This function receives a packet from a device driver and queues it for 5185 * the upper (protocol) levels to process via the backlog NAPI device. It 5186 * always succeeds. The buffer may be dropped during processing for 5187 * congestion control or by the protocol layers. 5188 * The network buffer is passed via the backlog NAPI device. Modern NIC 5189 * driver should use NAPI and GRO. 5190 * This function can used from interrupt and from process context. The 5191 * caller from process context must not disable interrupts before invoking 5192 * this function. 5193 * 5194 * return values: 5195 * NET_RX_SUCCESS (no congestion) 5196 * NET_RX_DROP (packet was dropped) 5197 * 5198 */ 5199 int netif_rx(struct sk_buff *skb) 5200 { 5201 bool need_bh_off = !(hardirq_count() | softirq_count()); 5202 int ret; 5203 5204 if (need_bh_off) 5205 local_bh_disable(); 5206 trace_netif_rx_entry(skb); 5207 ret = netif_rx_internal(skb); 5208 trace_netif_rx_exit(ret); 5209 if (need_bh_off) 5210 local_bh_enable(); 5211 return ret; 5212 } 5213 EXPORT_SYMBOL(netif_rx); 5214 5215 static __latent_entropy void net_tx_action(struct softirq_action *h) 5216 { 5217 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5218 5219 if (sd->completion_queue) { 5220 struct sk_buff *clist; 5221 5222 local_irq_disable(); 5223 clist = sd->completion_queue; 5224 sd->completion_queue = NULL; 5225 local_irq_enable(); 5226 5227 while (clist) { 5228 struct sk_buff *skb = clist; 5229 5230 clist = clist->next; 5231 5232 WARN_ON(refcount_read(&skb->users)); 5233 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED)) 5234 trace_consume_skb(skb, net_tx_action); 5235 else 5236 trace_kfree_skb(skb, net_tx_action, 5237 get_kfree_skb_cb(skb)->reason); 5238 5239 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5240 __kfree_skb(skb); 5241 else 5242 __napi_kfree_skb(skb, 5243 get_kfree_skb_cb(skb)->reason); 5244 } 5245 } 5246 5247 if (sd->output_queue) { 5248 struct Qdisc *head; 5249 5250 local_irq_disable(); 5251 head = sd->output_queue; 5252 sd->output_queue = NULL; 5253 sd->output_queue_tailp = &sd->output_queue; 5254 local_irq_enable(); 5255 5256 rcu_read_lock(); 5257 5258 while (head) { 5259 struct Qdisc *q = head; 5260 spinlock_t *root_lock = NULL; 5261 5262 head = head->next_sched; 5263 5264 /* We need to make sure head->next_sched is read 5265 * before clearing __QDISC_STATE_SCHED 5266 */ 5267 smp_mb__before_atomic(); 5268 5269 if (!(q->flags & TCQ_F_NOLOCK)) { 5270 root_lock = qdisc_lock(q); 5271 spin_lock(root_lock); 5272 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5273 &q->state))) { 5274 /* There is a synchronize_net() between 5275 * STATE_DEACTIVATED flag being set and 5276 * qdisc_reset()/some_qdisc_is_busy() in 5277 * dev_deactivate(), so we can safely bail out 5278 * early here to avoid data race between 5279 * qdisc_deactivate() and some_qdisc_is_busy() 5280 * for lockless qdisc. 5281 */ 5282 clear_bit(__QDISC_STATE_SCHED, &q->state); 5283 continue; 5284 } 5285 5286 clear_bit(__QDISC_STATE_SCHED, &q->state); 5287 qdisc_run(q); 5288 if (root_lock) 5289 spin_unlock(root_lock); 5290 } 5291 5292 rcu_read_unlock(); 5293 } 5294 5295 xfrm_dev_backlog(sd); 5296 } 5297 5298 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5299 /* This hook is defined here for ATM LANE */ 5300 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5301 unsigned char *addr) __read_mostly; 5302 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5303 #endif 5304 5305 /** 5306 * netdev_is_rx_handler_busy - check if receive handler is registered 5307 * @dev: device to check 5308 * 5309 * Check if a receive handler is already registered for a given device. 5310 * Return true if there one. 5311 * 5312 * The caller must hold the rtnl_mutex. 5313 */ 5314 bool netdev_is_rx_handler_busy(struct net_device *dev) 5315 { 5316 ASSERT_RTNL(); 5317 return dev && rtnl_dereference(dev->rx_handler); 5318 } 5319 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5320 5321 /** 5322 * netdev_rx_handler_register - register receive handler 5323 * @dev: device to register a handler for 5324 * @rx_handler: receive handler to register 5325 * @rx_handler_data: data pointer that is used by rx handler 5326 * 5327 * Register a receive handler for a device. This handler will then be 5328 * called from __netif_receive_skb. A negative errno code is returned 5329 * on a failure. 5330 * 5331 * The caller must hold the rtnl_mutex. 5332 * 5333 * For a general description of rx_handler, see enum rx_handler_result. 5334 */ 5335 int netdev_rx_handler_register(struct net_device *dev, 5336 rx_handler_func_t *rx_handler, 5337 void *rx_handler_data) 5338 { 5339 if (netdev_is_rx_handler_busy(dev)) 5340 return -EBUSY; 5341 5342 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5343 return -EINVAL; 5344 5345 /* Note: rx_handler_data must be set before rx_handler */ 5346 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5347 rcu_assign_pointer(dev->rx_handler, rx_handler); 5348 5349 return 0; 5350 } 5351 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5352 5353 /** 5354 * netdev_rx_handler_unregister - unregister receive handler 5355 * @dev: device to unregister a handler from 5356 * 5357 * Unregister a receive handler from a device. 5358 * 5359 * The caller must hold the rtnl_mutex. 5360 */ 5361 void netdev_rx_handler_unregister(struct net_device *dev) 5362 { 5363 5364 ASSERT_RTNL(); 5365 RCU_INIT_POINTER(dev->rx_handler, NULL); 5366 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5367 * section has a guarantee to see a non NULL rx_handler_data 5368 * as well. 5369 */ 5370 synchronize_net(); 5371 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5372 } 5373 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5374 5375 /* 5376 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5377 * the special handling of PFMEMALLOC skbs. 5378 */ 5379 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5380 { 5381 switch (skb->protocol) { 5382 case htons(ETH_P_ARP): 5383 case htons(ETH_P_IP): 5384 case htons(ETH_P_IPV6): 5385 case htons(ETH_P_8021Q): 5386 case htons(ETH_P_8021AD): 5387 return true; 5388 default: 5389 return false; 5390 } 5391 } 5392 5393 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5394 int *ret, struct net_device *orig_dev) 5395 { 5396 if (nf_hook_ingress_active(skb)) { 5397 int ingress_retval; 5398 5399 if (*pt_prev) { 5400 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5401 *pt_prev = NULL; 5402 } 5403 5404 rcu_read_lock(); 5405 ingress_retval = nf_hook_ingress(skb); 5406 rcu_read_unlock(); 5407 return ingress_retval; 5408 } 5409 return 0; 5410 } 5411 5412 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5413 struct packet_type **ppt_prev) 5414 { 5415 struct packet_type *ptype, *pt_prev; 5416 rx_handler_func_t *rx_handler; 5417 struct sk_buff *skb = *pskb; 5418 struct net_device *orig_dev; 5419 bool deliver_exact = false; 5420 int ret = NET_RX_DROP; 5421 __be16 type; 5422 5423 net_timestamp_check(!READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5424 5425 trace_netif_receive_skb(skb); 5426 5427 orig_dev = skb->dev; 5428 5429 skb_reset_network_header(skb); 5430 if (!skb_transport_header_was_set(skb)) 5431 skb_reset_transport_header(skb); 5432 skb_reset_mac_len(skb); 5433 5434 pt_prev = NULL; 5435 5436 another_round: 5437 skb->skb_iif = skb->dev->ifindex; 5438 5439 __this_cpu_inc(softnet_data.processed); 5440 5441 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5442 int ret2; 5443 5444 migrate_disable(); 5445 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), 5446 &skb); 5447 migrate_enable(); 5448 5449 if (ret2 != XDP_PASS) { 5450 ret = NET_RX_DROP; 5451 goto out; 5452 } 5453 } 5454 5455 if (eth_type_vlan(skb->protocol)) { 5456 skb = skb_vlan_untag(skb); 5457 if (unlikely(!skb)) 5458 goto out; 5459 } 5460 5461 if (skb_skip_tc_classify(skb)) 5462 goto skip_classify; 5463 5464 if (pfmemalloc) 5465 goto skip_taps; 5466 5467 list_for_each_entry_rcu(ptype, &net_hotdata.ptype_all, list) { 5468 if (pt_prev) 5469 ret = deliver_skb(skb, pt_prev, orig_dev); 5470 pt_prev = ptype; 5471 } 5472 5473 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5474 if (pt_prev) 5475 ret = deliver_skb(skb, pt_prev, orig_dev); 5476 pt_prev = ptype; 5477 } 5478 5479 skip_taps: 5480 #ifdef CONFIG_NET_INGRESS 5481 if (static_branch_unlikely(&ingress_needed_key)) { 5482 bool another = false; 5483 5484 nf_skip_egress(skb, true); 5485 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5486 &another); 5487 if (another) 5488 goto another_round; 5489 if (!skb) 5490 goto out; 5491 5492 nf_skip_egress(skb, false); 5493 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5494 goto out; 5495 } 5496 #endif 5497 skb_reset_redirect(skb); 5498 skip_classify: 5499 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5500 goto drop; 5501 5502 if (skb_vlan_tag_present(skb)) { 5503 if (pt_prev) { 5504 ret = deliver_skb(skb, pt_prev, orig_dev); 5505 pt_prev = NULL; 5506 } 5507 if (vlan_do_receive(&skb)) 5508 goto another_round; 5509 else if (unlikely(!skb)) 5510 goto out; 5511 } 5512 5513 rx_handler = rcu_dereference(skb->dev->rx_handler); 5514 if (rx_handler) { 5515 if (pt_prev) { 5516 ret = deliver_skb(skb, pt_prev, orig_dev); 5517 pt_prev = NULL; 5518 } 5519 switch (rx_handler(&skb)) { 5520 case RX_HANDLER_CONSUMED: 5521 ret = NET_RX_SUCCESS; 5522 goto out; 5523 case RX_HANDLER_ANOTHER: 5524 goto another_round; 5525 case RX_HANDLER_EXACT: 5526 deliver_exact = true; 5527 break; 5528 case RX_HANDLER_PASS: 5529 break; 5530 default: 5531 BUG(); 5532 } 5533 } 5534 5535 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5536 check_vlan_id: 5537 if (skb_vlan_tag_get_id(skb)) { 5538 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5539 * find vlan device. 5540 */ 5541 skb->pkt_type = PACKET_OTHERHOST; 5542 } else if (eth_type_vlan(skb->protocol)) { 5543 /* Outer header is 802.1P with vlan 0, inner header is 5544 * 802.1Q or 802.1AD and vlan_do_receive() above could 5545 * not find vlan dev for vlan id 0. 5546 */ 5547 __vlan_hwaccel_clear_tag(skb); 5548 skb = skb_vlan_untag(skb); 5549 if (unlikely(!skb)) 5550 goto out; 5551 if (vlan_do_receive(&skb)) 5552 /* After stripping off 802.1P header with vlan 0 5553 * vlan dev is found for inner header. 5554 */ 5555 goto another_round; 5556 else if (unlikely(!skb)) 5557 goto out; 5558 else 5559 /* We have stripped outer 802.1P vlan 0 header. 5560 * But could not find vlan dev. 5561 * check again for vlan id to set OTHERHOST. 5562 */ 5563 goto check_vlan_id; 5564 } 5565 /* Note: we might in the future use prio bits 5566 * and set skb->priority like in vlan_do_receive() 5567 * For the time being, just ignore Priority Code Point 5568 */ 5569 __vlan_hwaccel_clear_tag(skb); 5570 } 5571 5572 type = skb->protocol; 5573 5574 /* deliver only exact match when indicated */ 5575 if (likely(!deliver_exact)) { 5576 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5577 &ptype_base[ntohs(type) & 5578 PTYPE_HASH_MASK]); 5579 } 5580 5581 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5582 &orig_dev->ptype_specific); 5583 5584 if (unlikely(skb->dev != orig_dev)) { 5585 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5586 &skb->dev->ptype_specific); 5587 } 5588 5589 if (pt_prev) { 5590 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5591 goto drop; 5592 *ppt_prev = pt_prev; 5593 } else { 5594 drop: 5595 if (!deliver_exact) 5596 dev_core_stats_rx_dropped_inc(skb->dev); 5597 else 5598 dev_core_stats_rx_nohandler_inc(skb->dev); 5599 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5600 /* Jamal, now you will not able to escape explaining 5601 * me how you were going to use this. :-) 5602 */ 5603 ret = NET_RX_DROP; 5604 } 5605 5606 out: 5607 /* The invariant here is that if *ppt_prev is not NULL 5608 * then skb should also be non-NULL. 5609 * 5610 * Apparently *ppt_prev assignment above holds this invariant due to 5611 * skb dereferencing near it. 5612 */ 5613 *pskb = skb; 5614 return ret; 5615 } 5616 5617 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5618 { 5619 struct net_device *orig_dev = skb->dev; 5620 struct packet_type *pt_prev = NULL; 5621 int ret; 5622 5623 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5624 if (pt_prev) 5625 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5626 skb->dev, pt_prev, orig_dev); 5627 return ret; 5628 } 5629 5630 /** 5631 * netif_receive_skb_core - special purpose version of netif_receive_skb 5632 * @skb: buffer to process 5633 * 5634 * More direct receive version of netif_receive_skb(). It should 5635 * only be used by callers that have a need to skip RPS and Generic XDP. 5636 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5637 * 5638 * This function may only be called from softirq context and interrupts 5639 * should be enabled. 5640 * 5641 * Return values (usually ignored): 5642 * NET_RX_SUCCESS: no congestion 5643 * NET_RX_DROP: packet was dropped 5644 */ 5645 int netif_receive_skb_core(struct sk_buff *skb) 5646 { 5647 int ret; 5648 5649 rcu_read_lock(); 5650 ret = __netif_receive_skb_one_core(skb, false); 5651 rcu_read_unlock(); 5652 5653 return ret; 5654 } 5655 EXPORT_SYMBOL(netif_receive_skb_core); 5656 5657 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5658 struct packet_type *pt_prev, 5659 struct net_device *orig_dev) 5660 { 5661 struct sk_buff *skb, *next; 5662 5663 if (!pt_prev) 5664 return; 5665 if (list_empty(head)) 5666 return; 5667 if (pt_prev->list_func != NULL) 5668 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5669 ip_list_rcv, head, pt_prev, orig_dev); 5670 else 5671 list_for_each_entry_safe(skb, next, head, list) { 5672 skb_list_del_init(skb); 5673 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5674 } 5675 } 5676 5677 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5678 { 5679 /* Fast-path assumptions: 5680 * - There is no RX handler. 5681 * - Only one packet_type matches. 5682 * If either of these fails, we will end up doing some per-packet 5683 * processing in-line, then handling the 'last ptype' for the whole 5684 * sublist. This can't cause out-of-order delivery to any single ptype, 5685 * because the 'last ptype' must be constant across the sublist, and all 5686 * other ptypes are handled per-packet. 5687 */ 5688 /* Current (common) ptype of sublist */ 5689 struct packet_type *pt_curr = NULL; 5690 /* Current (common) orig_dev of sublist */ 5691 struct net_device *od_curr = NULL; 5692 struct list_head sublist; 5693 struct sk_buff *skb, *next; 5694 5695 INIT_LIST_HEAD(&sublist); 5696 list_for_each_entry_safe(skb, next, head, list) { 5697 struct net_device *orig_dev = skb->dev; 5698 struct packet_type *pt_prev = NULL; 5699 5700 skb_list_del_init(skb); 5701 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5702 if (!pt_prev) 5703 continue; 5704 if (pt_curr != pt_prev || od_curr != orig_dev) { 5705 /* dispatch old sublist */ 5706 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5707 /* start new sublist */ 5708 INIT_LIST_HEAD(&sublist); 5709 pt_curr = pt_prev; 5710 od_curr = orig_dev; 5711 } 5712 list_add_tail(&skb->list, &sublist); 5713 } 5714 5715 /* dispatch final sublist */ 5716 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5717 } 5718 5719 static int __netif_receive_skb(struct sk_buff *skb) 5720 { 5721 int ret; 5722 5723 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5724 unsigned int noreclaim_flag; 5725 5726 /* 5727 * PFMEMALLOC skbs are special, they should 5728 * - be delivered to SOCK_MEMALLOC sockets only 5729 * - stay away from userspace 5730 * - have bounded memory usage 5731 * 5732 * Use PF_MEMALLOC as this saves us from propagating the allocation 5733 * context down to all allocation sites. 5734 */ 5735 noreclaim_flag = memalloc_noreclaim_save(); 5736 ret = __netif_receive_skb_one_core(skb, true); 5737 memalloc_noreclaim_restore(noreclaim_flag); 5738 } else 5739 ret = __netif_receive_skb_one_core(skb, false); 5740 5741 return ret; 5742 } 5743 5744 static void __netif_receive_skb_list(struct list_head *head) 5745 { 5746 unsigned long noreclaim_flag = 0; 5747 struct sk_buff *skb, *next; 5748 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5749 5750 list_for_each_entry_safe(skb, next, head, list) { 5751 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5752 struct list_head sublist; 5753 5754 /* Handle the previous sublist */ 5755 list_cut_before(&sublist, head, &skb->list); 5756 if (!list_empty(&sublist)) 5757 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5758 pfmemalloc = !pfmemalloc; 5759 /* See comments in __netif_receive_skb */ 5760 if (pfmemalloc) 5761 noreclaim_flag = memalloc_noreclaim_save(); 5762 else 5763 memalloc_noreclaim_restore(noreclaim_flag); 5764 } 5765 } 5766 /* Handle the remaining sublist */ 5767 if (!list_empty(head)) 5768 __netif_receive_skb_list_core(head, pfmemalloc); 5769 /* Restore pflags */ 5770 if (pfmemalloc) 5771 memalloc_noreclaim_restore(noreclaim_flag); 5772 } 5773 5774 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5775 { 5776 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5777 struct bpf_prog *new = xdp->prog; 5778 int ret = 0; 5779 5780 switch (xdp->command) { 5781 case XDP_SETUP_PROG: 5782 rcu_assign_pointer(dev->xdp_prog, new); 5783 if (old) 5784 bpf_prog_put(old); 5785 5786 if (old && !new) { 5787 static_branch_dec(&generic_xdp_needed_key); 5788 } else if (new && !old) { 5789 static_branch_inc(&generic_xdp_needed_key); 5790 dev_disable_lro(dev); 5791 dev_disable_gro_hw(dev); 5792 } 5793 break; 5794 5795 default: 5796 ret = -EINVAL; 5797 break; 5798 } 5799 5800 return ret; 5801 } 5802 5803 static int netif_receive_skb_internal(struct sk_buff *skb) 5804 { 5805 int ret; 5806 5807 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5808 5809 if (skb_defer_rx_timestamp(skb)) 5810 return NET_RX_SUCCESS; 5811 5812 rcu_read_lock(); 5813 #ifdef CONFIG_RPS 5814 if (static_branch_unlikely(&rps_needed)) { 5815 struct rps_dev_flow voidflow, *rflow = &voidflow; 5816 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5817 5818 if (cpu >= 0) { 5819 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5820 rcu_read_unlock(); 5821 return ret; 5822 } 5823 } 5824 #endif 5825 ret = __netif_receive_skb(skb); 5826 rcu_read_unlock(); 5827 return ret; 5828 } 5829 5830 void netif_receive_skb_list_internal(struct list_head *head) 5831 { 5832 struct sk_buff *skb, *next; 5833 struct list_head sublist; 5834 5835 INIT_LIST_HEAD(&sublist); 5836 list_for_each_entry_safe(skb, next, head, list) { 5837 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), 5838 skb); 5839 skb_list_del_init(skb); 5840 if (!skb_defer_rx_timestamp(skb)) 5841 list_add_tail(&skb->list, &sublist); 5842 } 5843 list_splice_init(&sublist, head); 5844 5845 rcu_read_lock(); 5846 #ifdef CONFIG_RPS 5847 if (static_branch_unlikely(&rps_needed)) { 5848 list_for_each_entry_safe(skb, next, head, list) { 5849 struct rps_dev_flow voidflow, *rflow = &voidflow; 5850 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5851 5852 if (cpu >= 0) { 5853 /* Will be handled, remove from list */ 5854 skb_list_del_init(skb); 5855 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5856 } 5857 } 5858 } 5859 #endif 5860 __netif_receive_skb_list(head); 5861 rcu_read_unlock(); 5862 } 5863 5864 /** 5865 * netif_receive_skb - process receive buffer from network 5866 * @skb: buffer to process 5867 * 5868 * netif_receive_skb() is the main receive data processing function. 5869 * It always succeeds. The buffer may be dropped during processing 5870 * for congestion control or by the protocol layers. 5871 * 5872 * This function may only be called from softirq context and interrupts 5873 * should be enabled. 5874 * 5875 * Return values (usually ignored): 5876 * NET_RX_SUCCESS: no congestion 5877 * NET_RX_DROP: packet was dropped 5878 */ 5879 int netif_receive_skb(struct sk_buff *skb) 5880 { 5881 int ret; 5882 5883 trace_netif_receive_skb_entry(skb); 5884 5885 ret = netif_receive_skb_internal(skb); 5886 trace_netif_receive_skb_exit(ret); 5887 5888 return ret; 5889 } 5890 EXPORT_SYMBOL(netif_receive_skb); 5891 5892 /** 5893 * netif_receive_skb_list - process many receive buffers from network 5894 * @head: list of skbs to process. 5895 * 5896 * Since return value of netif_receive_skb() is normally ignored, and 5897 * wouldn't be meaningful for a list, this function returns void. 5898 * 5899 * This function may only be called from softirq context and interrupts 5900 * should be enabled. 5901 */ 5902 void netif_receive_skb_list(struct list_head *head) 5903 { 5904 struct sk_buff *skb; 5905 5906 if (list_empty(head)) 5907 return; 5908 if (trace_netif_receive_skb_list_entry_enabled()) { 5909 list_for_each_entry(skb, head, list) 5910 trace_netif_receive_skb_list_entry(skb); 5911 } 5912 netif_receive_skb_list_internal(head); 5913 trace_netif_receive_skb_list_exit(0); 5914 } 5915 EXPORT_SYMBOL(netif_receive_skb_list); 5916 5917 static DEFINE_PER_CPU(struct work_struct, flush_works); 5918 5919 /* Network device is going away, flush any packets still pending */ 5920 static void flush_backlog(struct work_struct *work) 5921 { 5922 struct sk_buff *skb, *tmp; 5923 struct softnet_data *sd; 5924 5925 local_bh_disable(); 5926 sd = this_cpu_ptr(&softnet_data); 5927 5928 backlog_lock_irq_disable(sd); 5929 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5930 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5931 __skb_unlink(skb, &sd->input_pkt_queue); 5932 dev_kfree_skb_irq(skb); 5933 rps_input_queue_head_incr(sd); 5934 } 5935 } 5936 backlog_unlock_irq_enable(sd); 5937 5938 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5939 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5940 __skb_unlink(skb, &sd->process_queue); 5941 kfree_skb(skb); 5942 rps_input_queue_head_incr(sd); 5943 } 5944 } 5945 local_bh_enable(); 5946 } 5947 5948 static bool flush_required(int cpu) 5949 { 5950 #if IS_ENABLED(CONFIG_RPS) 5951 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5952 bool do_flush; 5953 5954 backlog_lock_irq_disable(sd); 5955 5956 /* as insertion into process_queue happens with the rps lock held, 5957 * process_queue access may race only with dequeue 5958 */ 5959 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5960 !skb_queue_empty_lockless(&sd->process_queue); 5961 backlog_unlock_irq_enable(sd); 5962 5963 return do_flush; 5964 #endif 5965 /* without RPS we can't safely check input_pkt_queue: during a 5966 * concurrent remote skb_queue_splice() we can detect as empty both 5967 * input_pkt_queue and process_queue even if the latter could end-up 5968 * containing a lot of packets. 5969 */ 5970 return true; 5971 } 5972 5973 static void flush_all_backlogs(void) 5974 { 5975 static cpumask_t flush_cpus; 5976 unsigned int cpu; 5977 5978 /* since we are under rtnl lock protection we can use static data 5979 * for the cpumask and avoid allocating on stack the possibly 5980 * large mask 5981 */ 5982 ASSERT_RTNL(); 5983 5984 cpus_read_lock(); 5985 5986 cpumask_clear(&flush_cpus); 5987 for_each_online_cpu(cpu) { 5988 if (flush_required(cpu)) { 5989 queue_work_on(cpu, system_highpri_wq, 5990 per_cpu_ptr(&flush_works, cpu)); 5991 cpumask_set_cpu(cpu, &flush_cpus); 5992 } 5993 } 5994 5995 /* we can have in flight packet[s] on the cpus we are not flushing, 5996 * synchronize_net() in unregister_netdevice_many() will take care of 5997 * them 5998 */ 5999 for_each_cpu(cpu, &flush_cpus) 6000 flush_work(per_cpu_ptr(&flush_works, cpu)); 6001 6002 cpus_read_unlock(); 6003 } 6004 6005 static void net_rps_send_ipi(struct softnet_data *remsd) 6006 { 6007 #ifdef CONFIG_RPS 6008 while (remsd) { 6009 struct softnet_data *next = remsd->rps_ipi_next; 6010 6011 if (cpu_online(remsd->cpu)) 6012 smp_call_function_single_async(remsd->cpu, &remsd->csd); 6013 remsd = next; 6014 } 6015 #endif 6016 } 6017 6018 /* 6019 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 6020 * Note: called with local irq disabled, but exits with local irq enabled. 6021 */ 6022 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 6023 { 6024 #ifdef CONFIG_RPS 6025 struct softnet_data *remsd = sd->rps_ipi_list; 6026 6027 if (!use_backlog_threads() && remsd) { 6028 sd->rps_ipi_list = NULL; 6029 6030 local_irq_enable(); 6031 6032 /* Send pending IPI's to kick RPS processing on remote cpus. */ 6033 net_rps_send_ipi(remsd); 6034 } else 6035 #endif 6036 local_irq_enable(); 6037 } 6038 6039 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 6040 { 6041 #ifdef CONFIG_RPS 6042 return !use_backlog_threads() && sd->rps_ipi_list; 6043 #else 6044 return false; 6045 #endif 6046 } 6047 6048 static int process_backlog(struct napi_struct *napi, int quota) 6049 { 6050 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 6051 bool again = true; 6052 int work = 0; 6053 6054 /* Check if we have pending ipi, its better to send them now, 6055 * not waiting net_rx_action() end. 6056 */ 6057 if (sd_has_rps_ipi_waiting(sd)) { 6058 local_irq_disable(); 6059 net_rps_action_and_irq_enable(sd); 6060 } 6061 6062 napi->weight = READ_ONCE(net_hotdata.dev_rx_weight); 6063 while (again) { 6064 struct sk_buff *skb; 6065 6066 while ((skb = __skb_dequeue(&sd->process_queue))) { 6067 rcu_read_lock(); 6068 __netif_receive_skb(skb); 6069 rcu_read_unlock(); 6070 if (++work >= quota) { 6071 rps_input_queue_head_add(sd, work); 6072 return work; 6073 } 6074 6075 } 6076 6077 backlog_lock_irq_disable(sd); 6078 if (skb_queue_empty(&sd->input_pkt_queue)) { 6079 /* 6080 * Inline a custom version of __napi_complete(). 6081 * only current cpu owns and manipulates this napi, 6082 * and NAPI_STATE_SCHED is the only possible flag set 6083 * on backlog. 6084 * We can use a plain write instead of clear_bit(), 6085 * and we dont need an smp_mb() memory barrier. 6086 */ 6087 napi->state &= NAPIF_STATE_THREADED; 6088 again = false; 6089 } else { 6090 skb_queue_splice_tail_init(&sd->input_pkt_queue, 6091 &sd->process_queue); 6092 } 6093 backlog_unlock_irq_enable(sd); 6094 } 6095 6096 if (work) 6097 rps_input_queue_head_add(sd, work); 6098 return work; 6099 } 6100 6101 /** 6102 * __napi_schedule - schedule for receive 6103 * @n: entry to schedule 6104 * 6105 * The entry's receive function will be scheduled to run. 6106 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 6107 */ 6108 void __napi_schedule(struct napi_struct *n) 6109 { 6110 unsigned long flags; 6111 6112 local_irq_save(flags); 6113 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6114 local_irq_restore(flags); 6115 } 6116 EXPORT_SYMBOL(__napi_schedule); 6117 6118 /** 6119 * napi_schedule_prep - check if napi can be scheduled 6120 * @n: napi context 6121 * 6122 * Test if NAPI routine is already running, and if not mark 6123 * it as running. This is used as a condition variable to 6124 * insure only one NAPI poll instance runs. We also make 6125 * sure there is no pending NAPI disable. 6126 */ 6127 bool napi_schedule_prep(struct napi_struct *n) 6128 { 6129 unsigned long new, val = READ_ONCE(n->state); 6130 6131 do { 6132 if (unlikely(val & NAPIF_STATE_DISABLE)) 6133 return false; 6134 new = val | NAPIF_STATE_SCHED; 6135 6136 /* Sets STATE_MISSED bit if STATE_SCHED was already set 6137 * This was suggested by Alexander Duyck, as compiler 6138 * emits better code than : 6139 * if (val & NAPIF_STATE_SCHED) 6140 * new |= NAPIF_STATE_MISSED; 6141 */ 6142 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6143 NAPIF_STATE_MISSED; 6144 } while (!try_cmpxchg(&n->state, &val, new)); 6145 6146 return !(val & NAPIF_STATE_SCHED); 6147 } 6148 EXPORT_SYMBOL(napi_schedule_prep); 6149 6150 /** 6151 * __napi_schedule_irqoff - schedule for receive 6152 * @n: entry to schedule 6153 * 6154 * Variant of __napi_schedule() assuming hard irqs are masked. 6155 * 6156 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6157 * because the interrupt disabled assumption might not be true 6158 * due to force-threaded interrupts and spinlock substitution. 6159 */ 6160 void __napi_schedule_irqoff(struct napi_struct *n) 6161 { 6162 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6163 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6164 else 6165 __napi_schedule(n); 6166 } 6167 EXPORT_SYMBOL(__napi_schedule_irqoff); 6168 6169 bool napi_complete_done(struct napi_struct *n, int work_done) 6170 { 6171 unsigned long flags, val, new, timeout = 0; 6172 bool ret = true; 6173 6174 /* 6175 * 1) Don't let napi dequeue from the cpu poll list 6176 * just in case its running on a different cpu. 6177 * 2) If we are busy polling, do nothing here, we have 6178 * the guarantee we will be called later. 6179 */ 6180 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6181 NAPIF_STATE_IN_BUSY_POLL))) 6182 return false; 6183 6184 if (work_done) { 6185 if (n->gro_bitmask) 6186 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6187 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 6188 } 6189 if (n->defer_hard_irqs_count > 0) { 6190 n->defer_hard_irqs_count--; 6191 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6192 if (timeout) 6193 ret = false; 6194 } 6195 if (n->gro_bitmask) { 6196 /* When the NAPI instance uses a timeout and keeps postponing 6197 * it, we need to bound somehow the time packets are kept in 6198 * the GRO layer 6199 */ 6200 napi_gro_flush(n, !!timeout); 6201 } 6202 6203 gro_normal_list(n); 6204 6205 if (unlikely(!list_empty(&n->poll_list))) { 6206 /* If n->poll_list is not empty, we need to mask irqs */ 6207 local_irq_save(flags); 6208 list_del_init(&n->poll_list); 6209 local_irq_restore(flags); 6210 } 6211 WRITE_ONCE(n->list_owner, -1); 6212 6213 val = READ_ONCE(n->state); 6214 do { 6215 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6216 6217 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6218 NAPIF_STATE_SCHED_THREADED | 6219 NAPIF_STATE_PREFER_BUSY_POLL); 6220 6221 /* If STATE_MISSED was set, leave STATE_SCHED set, 6222 * because we will call napi->poll() one more time. 6223 * This C code was suggested by Alexander Duyck to help gcc. 6224 */ 6225 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6226 NAPIF_STATE_SCHED; 6227 } while (!try_cmpxchg(&n->state, &val, new)); 6228 6229 if (unlikely(val & NAPIF_STATE_MISSED)) { 6230 __napi_schedule(n); 6231 return false; 6232 } 6233 6234 if (timeout) 6235 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6236 HRTIMER_MODE_REL_PINNED); 6237 return ret; 6238 } 6239 EXPORT_SYMBOL(napi_complete_done); 6240 6241 /* must be called under rcu_read_lock(), as we dont take a reference */ 6242 struct napi_struct *napi_by_id(unsigned int napi_id) 6243 { 6244 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 6245 struct napi_struct *napi; 6246 6247 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 6248 if (napi->napi_id == napi_id) 6249 return napi; 6250 6251 return NULL; 6252 } 6253 6254 static void skb_defer_free_flush(struct softnet_data *sd) 6255 { 6256 struct sk_buff *skb, *next; 6257 6258 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6259 if (!READ_ONCE(sd->defer_list)) 6260 return; 6261 6262 spin_lock(&sd->defer_lock); 6263 skb = sd->defer_list; 6264 sd->defer_list = NULL; 6265 sd->defer_count = 0; 6266 spin_unlock(&sd->defer_lock); 6267 6268 while (skb != NULL) { 6269 next = skb->next; 6270 napi_consume_skb(skb, 1); 6271 skb = next; 6272 } 6273 } 6274 6275 #if defined(CONFIG_NET_RX_BUSY_POLL) 6276 6277 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6278 { 6279 if (!skip_schedule) { 6280 gro_normal_list(napi); 6281 __napi_schedule(napi); 6282 return; 6283 } 6284 6285 if (napi->gro_bitmask) { 6286 /* flush too old packets 6287 * If HZ < 1000, flush all packets. 6288 */ 6289 napi_gro_flush(napi, HZ >= 1000); 6290 } 6291 6292 gro_normal_list(napi); 6293 clear_bit(NAPI_STATE_SCHED, &napi->state); 6294 } 6295 6296 enum { 6297 NAPI_F_PREFER_BUSY_POLL = 1, 6298 NAPI_F_END_ON_RESCHED = 2, 6299 }; 6300 6301 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, 6302 unsigned flags, u16 budget) 6303 { 6304 bool skip_schedule = false; 6305 unsigned long timeout; 6306 int rc; 6307 6308 /* Busy polling means there is a high chance device driver hard irq 6309 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6310 * set in napi_schedule_prep(). 6311 * Since we are about to call napi->poll() once more, we can safely 6312 * clear NAPI_STATE_MISSED. 6313 * 6314 * Note: x86 could use a single "lock and ..." instruction 6315 * to perform these two clear_bit() 6316 */ 6317 clear_bit(NAPI_STATE_MISSED, &napi->state); 6318 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6319 6320 local_bh_disable(); 6321 6322 if (flags & NAPI_F_PREFER_BUSY_POLL) { 6323 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6324 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6325 if (napi->defer_hard_irqs_count && timeout) { 6326 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6327 skip_schedule = true; 6328 } 6329 } 6330 6331 /* All we really want here is to re-enable device interrupts. 6332 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6333 */ 6334 rc = napi->poll(napi, budget); 6335 /* We can't gro_normal_list() here, because napi->poll() might have 6336 * rearmed the napi (napi_complete_done()) in which case it could 6337 * already be running on another CPU. 6338 */ 6339 trace_napi_poll(napi, rc, budget); 6340 netpoll_poll_unlock(have_poll_lock); 6341 if (rc == budget) 6342 __busy_poll_stop(napi, skip_schedule); 6343 local_bh_enable(); 6344 } 6345 6346 static void __napi_busy_loop(unsigned int napi_id, 6347 bool (*loop_end)(void *, unsigned long), 6348 void *loop_end_arg, unsigned flags, u16 budget) 6349 { 6350 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6351 int (*napi_poll)(struct napi_struct *napi, int budget); 6352 void *have_poll_lock = NULL; 6353 struct napi_struct *napi; 6354 6355 WARN_ON_ONCE(!rcu_read_lock_held()); 6356 6357 restart: 6358 napi_poll = NULL; 6359 6360 napi = napi_by_id(napi_id); 6361 if (!napi) 6362 return; 6363 6364 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6365 preempt_disable(); 6366 for (;;) { 6367 int work = 0; 6368 6369 local_bh_disable(); 6370 if (!napi_poll) { 6371 unsigned long val = READ_ONCE(napi->state); 6372 6373 /* If multiple threads are competing for this napi, 6374 * we avoid dirtying napi->state as much as we can. 6375 */ 6376 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6377 NAPIF_STATE_IN_BUSY_POLL)) { 6378 if (flags & NAPI_F_PREFER_BUSY_POLL) 6379 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6380 goto count; 6381 } 6382 if (cmpxchg(&napi->state, val, 6383 val | NAPIF_STATE_IN_BUSY_POLL | 6384 NAPIF_STATE_SCHED) != val) { 6385 if (flags & NAPI_F_PREFER_BUSY_POLL) 6386 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6387 goto count; 6388 } 6389 have_poll_lock = netpoll_poll_lock(napi); 6390 napi_poll = napi->poll; 6391 } 6392 work = napi_poll(napi, budget); 6393 trace_napi_poll(napi, work, budget); 6394 gro_normal_list(napi); 6395 count: 6396 if (work > 0) 6397 __NET_ADD_STATS(dev_net(napi->dev), 6398 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6399 skb_defer_free_flush(this_cpu_ptr(&softnet_data)); 6400 local_bh_enable(); 6401 6402 if (!loop_end || loop_end(loop_end_arg, start_time)) 6403 break; 6404 6405 if (unlikely(need_resched())) { 6406 if (flags & NAPI_F_END_ON_RESCHED) 6407 break; 6408 if (napi_poll) 6409 busy_poll_stop(napi, have_poll_lock, flags, budget); 6410 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6411 preempt_enable(); 6412 rcu_read_unlock(); 6413 cond_resched(); 6414 rcu_read_lock(); 6415 if (loop_end(loop_end_arg, start_time)) 6416 return; 6417 goto restart; 6418 } 6419 cpu_relax(); 6420 } 6421 if (napi_poll) 6422 busy_poll_stop(napi, have_poll_lock, flags, budget); 6423 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6424 preempt_enable(); 6425 } 6426 6427 void napi_busy_loop_rcu(unsigned int napi_id, 6428 bool (*loop_end)(void *, unsigned long), 6429 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6430 { 6431 unsigned flags = NAPI_F_END_ON_RESCHED; 6432 6433 if (prefer_busy_poll) 6434 flags |= NAPI_F_PREFER_BUSY_POLL; 6435 6436 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6437 } 6438 6439 void napi_busy_loop(unsigned int napi_id, 6440 bool (*loop_end)(void *, unsigned long), 6441 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6442 { 6443 unsigned flags = prefer_busy_poll ? NAPI_F_PREFER_BUSY_POLL : 0; 6444 6445 rcu_read_lock(); 6446 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6447 rcu_read_unlock(); 6448 } 6449 EXPORT_SYMBOL(napi_busy_loop); 6450 6451 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6452 6453 static void napi_hash_add(struct napi_struct *napi) 6454 { 6455 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6456 return; 6457 6458 spin_lock(&napi_hash_lock); 6459 6460 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6461 do { 6462 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6463 napi_gen_id = MIN_NAPI_ID; 6464 } while (napi_by_id(napi_gen_id)); 6465 napi->napi_id = napi_gen_id; 6466 6467 hlist_add_head_rcu(&napi->napi_hash_node, 6468 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6469 6470 spin_unlock(&napi_hash_lock); 6471 } 6472 6473 /* Warning : caller is responsible to make sure rcu grace period 6474 * is respected before freeing memory containing @napi 6475 */ 6476 static void napi_hash_del(struct napi_struct *napi) 6477 { 6478 spin_lock(&napi_hash_lock); 6479 6480 hlist_del_init_rcu(&napi->napi_hash_node); 6481 6482 spin_unlock(&napi_hash_lock); 6483 } 6484 6485 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6486 { 6487 struct napi_struct *napi; 6488 6489 napi = container_of(timer, struct napi_struct, timer); 6490 6491 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6492 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6493 */ 6494 if (!napi_disable_pending(napi) && 6495 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6496 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6497 __napi_schedule_irqoff(napi); 6498 } 6499 6500 return HRTIMER_NORESTART; 6501 } 6502 6503 static void init_gro_hash(struct napi_struct *napi) 6504 { 6505 int i; 6506 6507 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6508 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6509 napi->gro_hash[i].count = 0; 6510 } 6511 napi->gro_bitmask = 0; 6512 } 6513 6514 int dev_set_threaded(struct net_device *dev, bool threaded) 6515 { 6516 struct napi_struct *napi; 6517 int err = 0; 6518 6519 if (dev->threaded == threaded) 6520 return 0; 6521 6522 if (threaded) { 6523 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6524 if (!napi->thread) { 6525 err = napi_kthread_create(napi); 6526 if (err) { 6527 threaded = false; 6528 break; 6529 } 6530 } 6531 } 6532 } 6533 6534 WRITE_ONCE(dev->threaded, threaded); 6535 6536 /* Make sure kthread is created before THREADED bit 6537 * is set. 6538 */ 6539 smp_mb__before_atomic(); 6540 6541 /* Setting/unsetting threaded mode on a napi might not immediately 6542 * take effect, if the current napi instance is actively being 6543 * polled. In this case, the switch between threaded mode and 6544 * softirq mode will happen in the next round of napi_schedule(). 6545 * This should not cause hiccups/stalls to the live traffic. 6546 */ 6547 list_for_each_entry(napi, &dev->napi_list, dev_list) 6548 assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); 6549 6550 return err; 6551 } 6552 EXPORT_SYMBOL(dev_set_threaded); 6553 6554 /** 6555 * netif_queue_set_napi - Associate queue with the napi 6556 * @dev: device to which NAPI and queue belong 6557 * @queue_index: Index of queue 6558 * @type: queue type as RX or TX 6559 * @napi: NAPI context, pass NULL to clear previously set NAPI 6560 * 6561 * Set queue with its corresponding napi context. This should be done after 6562 * registering the NAPI handler for the queue-vector and the queues have been 6563 * mapped to the corresponding interrupt vector. 6564 */ 6565 void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index, 6566 enum netdev_queue_type type, struct napi_struct *napi) 6567 { 6568 struct netdev_rx_queue *rxq; 6569 struct netdev_queue *txq; 6570 6571 if (WARN_ON_ONCE(napi && !napi->dev)) 6572 return; 6573 if (dev->reg_state >= NETREG_REGISTERED) 6574 ASSERT_RTNL(); 6575 6576 switch (type) { 6577 case NETDEV_QUEUE_TYPE_RX: 6578 rxq = __netif_get_rx_queue(dev, queue_index); 6579 rxq->napi = napi; 6580 return; 6581 case NETDEV_QUEUE_TYPE_TX: 6582 txq = netdev_get_tx_queue(dev, queue_index); 6583 txq->napi = napi; 6584 return; 6585 default: 6586 return; 6587 } 6588 } 6589 EXPORT_SYMBOL(netif_queue_set_napi); 6590 6591 void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, 6592 int (*poll)(struct napi_struct *, int), int weight) 6593 { 6594 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6595 return; 6596 6597 INIT_LIST_HEAD(&napi->poll_list); 6598 INIT_HLIST_NODE(&napi->napi_hash_node); 6599 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6600 napi->timer.function = napi_watchdog; 6601 init_gro_hash(napi); 6602 napi->skb = NULL; 6603 INIT_LIST_HEAD(&napi->rx_list); 6604 napi->rx_count = 0; 6605 napi->poll = poll; 6606 if (weight > NAPI_POLL_WEIGHT) 6607 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6608 weight); 6609 napi->weight = weight; 6610 napi->dev = dev; 6611 #ifdef CONFIG_NETPOLL 6612 napi->poll_owner = -1; 6613 #endif 6614 napi->list_owner = -1; 6615 set_bit(NAPI_STATE_SCHED, &napi->state); 6616 set_bit(NAPI_STATE_NPSVC, &napi->state); 6617 list_add_rcu(&napi->dev_list, &dev->napi_list); 6618 napi_hash_add(napi); 6619 napi_get_frags_check(napi); 6620 /* Create kthread for this napi if dev->threaded is set. 6621 * Clear dev->threaded if kthread creation failed so that 6622 * threaded mode will not be enabled in napi_enable(). 6623 */ 6624 if (dev->threaded && napi_kthread_create(napi)) 6625 dev->threaded = false; 6626 netif_napi_set_irq(napi, -1); 6627 } 6628 EXPORT_SYMBOL(netif_napi_add_weight); 6629 6630 void napi_disable(struct napi_struct *n) 6631 { 6632 unsigned long val, new; 6633 6634 might_sleep(); 6635 set_bit(NAPI_STATE_DISABLE, &n->state); 6636 6637 val = READ_ONCE(n->state); 6638 do { 6639 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6640 usleep_range(20, 200); 6641 val = READ_ONCE(n->state); 6642 } 6643 6644 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6645 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6646 } while (!try_cmpxchg(&n->state, &val, new)); 6647 6648 hrtimer_cancel(&n->timer); 6649 6650 clear_bit(NAPI_STATE_DISABLE, &n->state); 6651 } 6652 EXPORT_SYMBOL(napi_disable); 6653 6654 /** 6655 * napi_enable - enable NAPI scheduling 6656 * @n: NAPI context 6657 * 6658 * Resume NAPI from being scheduled on this context. 6659 * Must be paired with napi_disable. 6660 */ 6661 void napi_enable(struct napi_struct *n) 6662 { 6663 unsigned long new, val = READ_ONCE(n->state); 6664 6665 do { 6666 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6667 6668 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6669 if (n->dev->threaded && n->thread) 6670 new |= NAPIF_STATE_THREADED; 6671 } while (!try_cmpxchg(&n->state, &val, new)); 6672 } 6673 EXPORT_SYMBOL(napi_enable); 6674 6675 static void flush_gro_hash(struct napi_struct *napi) 6676 { 6677 int i; 6678 6679 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6680 struct sk_buff *skb, *n; 6681 6682 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6683 kfree_skb(skb); 6684 napi->gro_hash[i].count = 0; 6685 } 6686 } 6687 6688 /* Must be called in process context */ 6689 void __netif_napi_del(struct napi_struct *napi) 6690 { 6691 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6692 return; 6693 6694 napi_hash_del(napi); 6695 list_del_rcu(&napi->dev_list); 6696 napi_free_frags(napi); 6697 6698 flush_gro_hash(napi); 6699 napi->gro_bitmask = 0; 6700 6701 if (napi->thread) { 6702 kthread_stop(napi->thread); 6703 napi->thread = NULL; 6704 } 6705 } 6706 EXPORT_SYMBOL(__netif_napi_del); 6707 6708 static int __napi_poll(struct napi_struct *n, bool *repoll) 6709 { 6710 int work, weight; 6711 6712 weight = n->weight; 6713 6714 /* This NAPI_STATE_SCHED test is for avoiding a race 6715 * with netpoll's poll_napi(). Only the entity which 6716 * obtains the lock and sees NAPI_STATE_SCHED set will 6717 * actually make the ->poll() call. Therefore we avoid 6718 * accidentally calling ->poll() when NAPI is not scheduled. 6719 */ 6720 work = 0; 6721 if (napi_is_scheduled(n)) { 6722 work = n->poll(n, weight); 6723 trace_napi_poll(n, work, weight); 6724 6725 xdp_do_check_flushed(n); 6726 } 6727 6728 if (unlikely(work > weight)) 6729 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6730 n->poll, work, weight); 6731 6732 if (likely(work < weight)) 6733 return work; 6734 6735 /* Drivers must not modify the NAPI state if they 6736 * consume the entire weight. In such cases this code 6737 * still "owns" the NAPI instance and therefore can 6738 * move the instance around on the list at-will. 6739 */ 6740 if (unlikely(napi_disable_pending(n))) { 6741 napi_complete(n); 6742 return work; 6743 } 6744 6745 /* The NAPI context has more processing work, but busy-polling 6746 * is preferred. Exit early. 6747 */ 6748 if (napi_prefer_busy_poll(n)) { 6749 if (napi_complete_done(n, work)) { 6750 /* If timeout is not set, we need to make sure 6751 * that the NAPI is re-scheduled. 6752 */ 6753 napi_schedule(n); 6754 } 6755 return work; 6756 } 6757 6758 if (n->gro_bitmask) { 6759 /* flush too old packets 6760 * If HZ < 1000, flush all packets. 6761 */ 6762 napi_gro_flush(n, HZ >= 1000); 6763 } 6764 6765 gro_normal_list(n); 6766 6767 /* Some drivers may have called napi_schedule 6768 * prior to exhausting their budget. 6769 */ 6770 if (unlikely(!list_empty(&n->poll_list))) { 6771 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6772 n->dev ? n->dev->name : "backlog"); 6773 return work; 6774 } 6775 6776 *repoll = true; 6777 6778 return work; 6779 } 6780 6781 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6782 { 6783 bool do_repoll = false; 6784 void *have; 6785 int work; 6786 6787 list_del_init(&n->poll_list); 6788 6789 have = netpoll_poll_lock(n); 6790 6791 work = __napi_poll(n, &do_repoll); 6792 6793 if (do_repoll) 6794 list_add_tail(&n->poll_list, repoll); 6795 6796 netpoll_poll_unlock(have); 6797 6798 return work; 6799 } 6800 6801 static int napi_thread_wait(struct napi_struct *napi) 6802 { 6803 set_current_state(TASK_INTERRUPTIBLE); 6804 6805 while (!kthread_should_stop()) { 6806 /* Testing SCHED_THREADED bit here to make sure the current 6807 * kthread owns this napi and could poll on this napi. 6808 * Testing SCHED bit is not enough because SCHED bit might be 6809 * set by some other busy poll thread or by napi_disable(). 6810 */ 6811 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state)) { 6812 WARN_ON(!list_empty(&napi->poll_list)); 6813 __set_current_state(TASK_RUNNING); 6814 return 0; 6815 } 6816 6817 schedule(); 6818 set_current_state(TASK_INTERRUPTIBLE); 6819 } 6820 __set_current_state(TASK_RUNNING); 6821 6822 return -1; 6823 } 6824 6825 static void napi_threaded_poll_loop(struct napi_struct *napi) 6826 { 6827 struct softnet_data *sd; 6828 unsigned long last_qs = jiffies; 6829 6830 for (;;) { 6831 bool repoll = false; 6832 void *have; 6833 6834 local_bh_disable(); 6835 sd = this_cpu_ptr(&softnet_data); 6836 sd->in_napi_threaded_poll = true; 6837 6838 have = netpoll_poll_lock(napi); 6839 __napi_poll(napi, &repoll); 6840 netpoll_poll_unlock(have); 6841 6842 sd->in_napi_threaded_poll = false; 6843 barrier(); 6844 6845 if (sd_has_rps_ipi_waiting(sd)) { 6846 local_irq_disable(); 6847 net_rps_action_and_irq_enable(sd); 6848 } 6849 skb_defer_free_flush(sd); 6850 local_bh_enable(); 6851 6852 if (!repoll) 6853 break; 6854 6855 rcu_softirq_qs_periodic(last_qs); 6856 cond_resched(); 6857 } 6858 } 6859 6860 static int napi_threaded_poll(void *data) 6861 { 6862 struct napi_struct *napi = data; 6863 6864 while (!napi_thread_wait(napi)) 6865 napi_threaded_poll_loop(napi); 6866 6867 return 0; 6868 } 6869 6870 static __latent_entropy void net_rx_action(struct softirq_action *h) 6871 { 6872 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6873 unsigned long time_limit = jiffies + 6874 usecs_to_jiffies(READ_ONCE(net_hotdata.netdev_budget_usecs)); 6875 int budget = READ_ONCE(net_hotdata.netdev_budget); 6876 LIST_HEAD(list); 6877 LIST_HEAD(repoll); 6878 6879 start: 6880 sd->in_net_rx_action = true; 6881 local_irq_disable(); 6882 list_splice_init(&sd->poll_list, &list); 6883 local_irq_enable(); 6884 6885 for (;;) { 6886 struct napi_struct *n; 6887 6888 skb_defer_free_flush(sd); 6889 6890 if (list_empty(&list)) { 6891 if (list_empty(&repoll)) { 6892 sd->in_net_rx_action = false; 6893 barrier(); 6894 /* We need to check if ____napi_schedule() 6895 * had refilled poll_list while 6896 * sd->in_net_rx_action was true. 6897 */ 6898 if (!list_empty(&sd->poll_list)) 6899 goto start; 6900 if (!sd_has_rps_ipi_waiting(sd)) 6901 goto end; 6902 } 6903 break; 6904 } 6905 6906 n = list_first_entry(&list, struct napi_struct, poll_list); 6907 budget -= napi_poll(n, &repoll); 6908 6909 /* If softirq window is exhausted then punt. 6910 * Allow this to run for 2 jiffies since which will allow 6911 * an average latency of 1.5/HZ. 6912 */ 6913 if (unlikely(budget <= 0 || 6914 time_after_eq(jiffies, time_limit))) { 6915 sd->time_squeeze++; 6916 break; 6917 } 6918 } 6919 6920 local_irq_disable(); 6921 6922 list_splice_tail_init(&sd->poll_list, &list); 6923 list_splice_tail(&repoll, &list); 6924 list_splice(&list, &sd->poll_list); 6925 if (!list_empty(&sd->poll_list)) 6926 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6927 else 6928 sd->in_net_rx_action = false; 6929 6930 net_rps_action_and_irq_enable(sd); 6931 end:; 6932 } 6933 6934 struct netdev_adjacent { 6935 struct net_device *dev; 6936 netdevice_tracker dev_tracker; 6937 6938 /* upper master flag, there can only be one master device per list */ 6939 bool master; 6940 6941 /* lookup ignore flag */ 6942 bool ignore; 6943 6944 /* counter for the number of times this device was added to us */ 6945 u16 ref_nr; 6946 6947 /* private field for the users */ 6948 void *private; 6949 6950 struct list_head list; 6951 struct rcu_head rcu; 6952 }; 6953 6954 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6955 struct list_head *adj_list) 6956 { 6957 struct netdev_adjacent *adj; 6958 6959 list_for_each_entry(adj, adj_list, list) { 6960 if (adj->dev == adj_dev) 6961 return adj; 6962 } 6963 return NULL; 6964 } 6965 6966 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6967 struct netdev_nested_priv *priv) 6968 { 6969 struct net_device *dev = (struct net_device *)priv->data; 6970 6971 return upper_dev == dev; 6972 } 6973 6974 /** 6975 * netdev_has_upper_dev - Check if device is linked to an upper device 6976 * @dev: device 6977 * @upper_dev: upper device to check 6978 * 6979 * Find out if a device is linked to specified upper device and return true 6980 * in case it is. Note that this checks only immediate upper device, 6981 * not through a complete stack of devices. The caller must hold the RTNL lock. 6982 */ 6983 bool netdev_has_upper_dev(struct net_device *dev, 6984 struct net_device *upper_dev) 6985 { 6986 struct netdev_nested_priv priv = { 6987 .data = (void *)upper_dev, 6988 }; 6989 6990 ASSERT_RTNL(); 6991 6992 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6993 &priv); 6994 } 6995 EXPORT_SYMBOL(netdev_has_upper_dev); 6996 6997 /** 6998 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6999 * @dev: device 7000 * @upper_dev: upper device to check 7001 * 7002 * Find out if a device is linked to specified upper device and return true 7003 * in case it is. Note that this checks the entire upper device chain. 7004 * The caller must hold rcu lock. 7005 */ 7006 7007 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 7008 struct net_device *upper_dev) 7009 { 7010 struct netdev_nested_priv priv = { 7011 .data = (void *)upper_dev, 7012 }; 7013 7014 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 7015 &priv); 7016 } 7017 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 7018 7019 /** 7020 * netdev_has_any_upper_dev - Check if device is linked to some device 7021 * @dev: device 7022 * 7023 * Find out if a device is linked to an upper device and return true in case 7024 * it is. The caller must hold the RTNL lock. 7025 */ 7026 bool netdev_has_any_upper_dev(struct net_device *dev) 7027 { 7028 ASSERT_RTNL(); 7029 7030 return !list_empty(&dev->adj_list.upper); 7031 } 7032 EXPORT_SYMBOL(netdev_has_any_upper_dev); 7033 7034 /** 7035 * netdev_master_upper_dev_get - Get master upper device 7036 * @dev: device 7037 * 7038 * Find a master upper device and return pointer to it or NULL in case 7039 * it's not there. The caller must hold the RTNL lock. 7040 */ 7041 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 7042 { 7043 struct netdev_adjacent *upper; 7044 7045 ASSERT_RTNL(); 7046 7047 if (list_empty(&dev->adj_list.upper)) 7048 return NULL; 7049 7050 upper = list_first_entry(&dev->adj_list.upper, 7051 struct netdev_adjacent, list); 7052 if (likely(upper->master)) 7053 return upper->dev; 7054 return NULL; 7055 } 7056 EXPORT_SYMBOL(netdev_master_upper_dev_get); 7057 7058 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 7059 { 7060 struct netdev_adjacent *upper; 7061 7062 ASSERT_RTNL(); 7063 7064 if (list_empty(&dev->adj_list.upper)) 7065 return NULL; 7066 7067 upper = list_first_entry(&dev->adj_list.upper, 7068 struct netdev_adjacent, list); 7069 if (likely(upper->master) && !upper->ignore) 7070 return upper->dev; 7071 return NULL; 7072 } 7073 7074 /** 7075 * netdev_has_any_lower_dev - Check if device is linked to some device 7076 * @dev: device 7077 * 7078 * Find out if a device is linked to a lower device and return true in case 7079 * it is. The caller must hold the RTNL lock. 7080 */ 7081 static bool netdev_has_any_lower_dev(struct net_device *dev) 7082 { 7083 ASSERT_RTNL(); 7084 7085 return !list_empty(&dev->adj_list.lower); 7086 } 7087 7088 void *netdev_adjacent_get_private(struct list_head *adj_list) 7089 { 7090 struct netdev_adjacent *adj; 7091 7092 adj = list_entry(adj_list, struct netdev_adjacent, list); 7093 7094 return adj->private; 7095 } 7096 EXPORT_SYMBOL(netdev_adjacent_get_private); 7097 7098 /** 7099 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 7100 * @dev: device 7101 * @iter: list_head ** of the current position 7102 * 7103 * Gets the next device from the dev's upper list, starting from iter 7104 * position. The caller must hold RCU read lock. 7105 */ 7106 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 7107 struct list_head **iter) 7108 { 7109 struct netdev_adjacent *upper; 7110 7111 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 7112 7113 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7114 7115 if (&upper->list == &dev->adj_list.upper) 7116 return NULL; 7117 7118 *iter = &upper->list; 7119 7120 return upper->dev; 7121 } 7122 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 7123 7124 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 7125 struct list_head **iter, 7126 bool *ignore) 7127 { 7128 struct netdev_adjacent *upper; 7129 7130 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 7131 7132 if (&upper->list == &dev->adj_list.upper) 7133 return NULL; 7134 7135 *iter = &upper->list; 7136 *ignore = upper->ignore; 7137 7138 return upper->dev; 7139 } 7140 7141 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 7142 struct list_head **iter) 7143 { 7144 struct netdev_adjacent *upper; 7145 7146 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 7147 7148 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7149 7150 if (&upper->list == &dev->adj_list.upper) 7151 return NULL; 7152 7153 *iter = &upper->list; 7154 7155 return upper->dev; 7156 } 7157 7158 static int __netdev_walk_all_upper_dev(struct net_device *dev, 7159 int (*fn)(struct net_device *dev, 7160 struct netdev_nested_priv *priv), 7161 struct netdev_nested_priv *priv) 7162 { 7163 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7164 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7165 int ret, cur = 0; 7166 bool ignore; 7167 7168 now = dev; 7169 iter = &dev->adj_list.upper; 7170 7171 while (1) { 7172 if (now != dev) { 7173 ret = fn(now, priv); 7174 if (ret) 7175 return ret; 7176 } 7177 7178 next = NULL; 7179 while (1) { 7180 udev = __netdev_next_upper_dev(now, &iter, &ignore); 7181 if (!udev) 7182 break; 7183 if (ignore) 7184 continue; 7185 7186 next = udev; 7187 niter = &udev->adj_list.upper; 7188 dev_stack[cur] = now; 7189 iter_stack[cur++] = iter; 7190 break; 7191 } 7192 7193 if (!next) { 7194 if (!cur) 7195 return 0; 7196 next = dev_stack[--cur]; 7197 niter = iter_stack[cur]; 7198 } 7199 7200 now = next; 7201 iter = niter; 7202 } 7203 7204 return 0; 7205 } 7206 7207 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 7208 int (*fn)(struct net_device *dev, 7209 struct netdev_nested_priv *priv), 7210 struct netdev_nested_priv *priv) 7211 { 7212 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7213 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7214 int ret, cur = 0; 7215 7216 now = dev; 7217 iter = &dev->adj_list.upper; 7218 7219 while (1) { 7220 if (now != dev) { 7221 ret = fn(now, priv); 7222 if (ret) 7223 return ret; 7224 } 7225 7226 next = NULL; 7227 while (1) { 7228 udev = netdev_next_upper_dev_rcu(now, &iter); 7229 if (!udev) 7230 break; 7231 7232 next = udev; 7233 niter = &udev->adj_list.upper; 7234 dev_stack[cur] = now; 7235 iter_stack[cur++] = iter; 7236 break; 7237 } 7238 7239 if (!next) { 7240 if (!cur) 7241 return 0; 7242 next = dev_stack[--cur]; 7243 niter = iter_stack[cur]; 7244 } 7245 7246 now = next; 7247 iter = niter; 7248 } 7249 7250 return 0; 7251 } 7252 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 7253 7254 static bool __netdev_has_upper_dev(struct net_device *dev, 7255 struct net_device *upper_dev) 7256 { 7257 struct netdev_nested_priv priv = { 7258 .flags = 0, 7259 .data = (void *)upper_dev, 7260 }; 7261 7262 ASSERT_RTNL(); 7263 7264 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 7265 &priv); 7266 } 7267 7268 /** 7269 * netdev_lower_get_next_private - Get the next ->private from the 7270 * lower neighbour list 7271 * @dev: device 7272 * @iter: list_head ** of the current position 7273 * 7274 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7275 * list, starting from iter position. The caller must hold either hold the 7276 * RTNL lock or its own locking that guarantees that the neighbour lower 7277 * list will remain unchanged. 7278 */ 7279 void *netdev_lower_get_next_private(struct net_device *dev, 7280 struct list_head **iter) 7281 { 7282 struct netdev_adjacent *lower; 7283 7284 lower = list_entry(*iter, struct netdev_adjacent, list); 7285 7286 if (&lower->list == &dev->adj_list.lower) 7287 return NULL; 7288 7289 *iter = lower->list.next; 7290 7291 return lower->private; 7292 } 7293 EXPORT_SYMBOL(netdev_lower_get_next_private); 7294 7295 /** 7296 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7297 * lower neighbour list, RCU 7298 * variant 7299 * @dev: device 7300 * @iter: list_head ** of the current position 7301 * 7302 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7303 * list, starting from iter position. The caller must hold RCU read lock. 7304 */ 7305 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7306 struct list_head **iter) 7307 { 7308 struct netdev_adjacent *lower; 7309 7310 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7311 7312 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7313 7314 if (&lower->list == &dev->adj_list.lower) 7315 return NULL; 7316 7317 *iter = &lower->list; 7318 7319 return lower->private; 7320 } 7321 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7322 7323 /** 7324 * netdev_lower_get_next - Get the next device from the lower neighbour 7325 * list 7326 * @dev: device 7327 * @iter: list_head ** of the current position 7328 * 7329 * Gets the next netdev_adjacent from the dev's lower neighbour 7330 * list, starting from iter position. The caller must hold RTNL lock or 7331 * its own locking that guarantees that the neighbour lower 7332 * list will remain unchanged. 7333 */ 7334 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7335 { 7336 struct netdev_adjacent *lower; 7337 7338 lower = list_entry(*iter, struct netdev_adjacent, list); 7339 7340 if (&lower->list == &dev->adj_list.lower) 7341 return NULL; 7342 7343 *iter = lower->list.next; 7344 7345 return lower->dev; 7346 } 7347 EXPORT_SYMBOL(netdev_lower_get_next); 7348 7349 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7350 struct list_head **iter) 7351 { 7352 struct netdev_adjacent *lower; 7353 7354 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7355 7356 if (&lower->list == &dev->adj_list.lower) 7357 return NULL; 7358 7359 *iter = &lower->list; 7360 7361 return lower->dev; 7362 } 7363 7364 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7365 struct list_head **iter, 7366 bool *ignore) 7367 { 7368 struct netdev_adjacent *lower; 7369 7370 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7371 7372 if (&lower->list == &dev->adj_list.lower) 7373 return NULL; 7374 7375 *iter = &lower->list; 7376 *ignore = lower->ignore; 7377 7378 return lower->dev; 7379 } 7380 7381 int netdev_walk_all_lower_dev(struct net_device *dev, 7382 int (*fn)(struct net_device *dev, 7383 struct netdev_nested_priv *priv), 7384 struct netdev_nested_priv *priv) 7385 { 7386 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7387 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7388 int ret, cur = 0; 7389 7390 now = dev; 7391 iter = &dev->adj_list.lower; 7392 7393 while (1) { 7394 if (now != dev) { 7395 ret = fn(now, priv); 7396 if (ret) 7397 return ret; 7398 } 7399 7400 next = NULL; 7401 while (1) { 7402 ldev = netdev_next_lower_dev(now, &iter); 7403 if (!ldev) 7404 break; 7405 7406 next = ldev; 7407 niter = &ldev->adj_list.lower; 7408 dev_stack[cur] = now; 7409 iter_stack[cur++] = iter; 7410 break; 7411 } 7412 7413 if (!next) { 7414 if (!cur) 7415 return 0; 7416 next = dev_stack[--cur]; 7417 niter = iter_stack[cur]; 7418 } 7419 7420 now = next; 7421 iter = niter; 7422 } 7423 7424 return 0; 7425 } 7426 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7427 7428 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7429 int (*fn)(struct net_device *dev, 7430 struct netdev_nested_priv *priv), 7431 struct netdev_nested_priv *priv) 7432 { 7433 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7434 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7435 int ret, cur = 0; 7436 bool ignore; 7437 7438 now = dev; 7439 iter = &dev->adj_list.lower; 7440 7441 while (1) { 7442 if (now != dev) { 7443 ret = fn(now, priv); 7444 if (ret) 7445 return ret; 7446 } 7447 7448 next = NULL; 7449 while (1) { 7450 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7451 if (!ldev) 7452 break; 7453 if (ignore) 7454 continue; 7455 7456 next = ldev; 7457 niter = &ldev->adj_list.lower; 7458 dev_stack[cur] = now; 7459 iter_stack[cur++] = iter; 7460 break; 7461 } 7462 7463 if (!next) { 7464 if (!cur) 7465 return 0; 7466 next = dev_stack[--cur]; 7467 niter = iter_stack[cur]; 7468 } 7469 7470 now = next; 7471 iter = niter; 7472 } 7473 7474 return 0; 7475 } 7476 7477 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7478 struct list_head **iter) 7479 { 7480 struct netdev_adjacent *lower; 7481 7482 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7483 if (&lower->list == &dev->adj_list.lower) 7484 return NULL; 7485 7486 *iter = &lower->list; 7487 7488 return lower->dev; 7489 } 7490 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7491 7492 static u8 __netdev_upper_depth(struct net_device *dev) 7493 { 7494 struct net_device *udev; 7495 struct list_head *iter; 7496 u8 max_depth = 0; 7497 bool ignore; 7498 7499 for (iter = &dev->adj_list.upper, 7500 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7501 udev; 7502 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7503 if (ignore) 7504 continue; 7505 if (max_depth < udev->upper_level) 7506 max_depth = udev->upper_level; 7507 } 7508 7509 return max_depth; 7510 } 7511 7512 static u8 __netdev_lower_depth(struct net_device *dev) 7513 { 7514 struct net_device *ldev; 7515 struct list_head *iter; 7516 u8 max_depth = 0; 7517 bool ignore; 7518 7519 for (iter = &dev->adj_list.lower, 7520 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7521 ldev; 7522 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7523 if (ignore) 7524 continue; 7525 if (max_depth < ldev->lower_level) 7526 max_depth = ldev->lower_level; 7527 } 7528 7529 return max_depth; 7530 } 7531 7532 static int __netdev_update_upper_level(struct net_device *dev, 7533 struct netdev_nested_priv *__unused) 7534 { 7535 dev->upper_level = __netdev_upper_depth(dev) + 1; 7536 return 0; 7537 } 7538 7539 #ifdef CONFIG_LOCKDEP 7540 static LIST_HEAD(net_unlink_list); 7541 7542 static void net_unlink_todo(struct net_device *dev) 7543 { 7544 if (list_empty(&dev->unlink_list)) 7545 list_add_tail(&dev->unlink_list, &net_unlink_list); 7546 } 7547 #endif 7548 7549 static int __netdev_update_lower_level(struct net_device *dev, 7550 struct netdev_nested_priv *priv) 7551 { 7552 dev->lower_level = __netdev_lower_depth(dev) + 1; 7553 7554 #ifdef CONFIG_LOCKDEP 7555 if (!priv) 7556 return 0; 7557 7558 if (priv->flags & NESTED_SYNC_IMM) 7559 dev->nested_level = dev->lower_level - 1; 7560 if (priv->flags & NESTED_SYNC_TODO) 7561 net_unlink_todo(dev); 7562 #endif 7563 return 0; 7564 } 7565 7566 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7567 int (*fn)(struct net_device *dev, 7568 struct netdev_nested_priv *priv), 7569 struct netdev_nested_priv *priv) 7570 { 7571 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7572 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7573 int ret, cur = 0; 7574 7575 now = dev; 7576 iter = &dev->adj_list.lower; 7577 7578 while (1) { 7579 if (now != dev) { 7580 ret = fn(now, priv); 7581 if (ret) 7582 return ret; 7583 } 7584 7585 next = NULL; 7586 while (1) { 7587 ldev = netdev_next_lower_dev_rcu(now, &iter); 7588 if (!ldev) 7589 break; 7590 7591 next = ldev; 7592 niter = &ldev->adj_list.lower; 7593 dev_stack[cur] = now; 7594 iter_stack[cur++] = iter; 7595 break; 7596 } 7597 7598 if (!next) { 7599 if (!cur) 7600 return 0; 7601 next = dev_stack[--cur]; 7602 niter = iter_stack[cur]; 7603 } 7604 7605 now = next; 7606 iter = niter; 7607 } 7608 7609 return 0; 7610 } 7611 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7612 7613 /** 7614 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7615 * lower neighbour list, RCU 7616 * variant 7617 * @dev: device 7618 * 7619 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7620 * list. The caller must hold RCU read lock. 7621 */ 7622 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7623 { 7624 struct netdev_adjacent *lower; 7625 7626 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7627 struct netdev_adjacent, list); 7628 if (lower) 7629 return lower->private; 7630 return NULL; 7631 } 7632 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7633 7634 /** 7635 * netdev_master_upper_dev_get_rcu - Get master upper device 7636 * @dev: device 7637 * 7638 * Find a master upper device and return pointer to it or NULL in case 7639 * it's not there. The caller must hold the RCU read lock. 7640 */ 7641 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7642 { 7643 struct netdev_adjacent *upper; 7644 7645 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7646 struct netdev_adjacent, list); 7647 if (upper && likely(upper->master)) 7648 return upper->dev; 7649 return NULL; 7650 } 7651 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7652 7653 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7654 struct net_device *adj_dev, 7655 struct list_head *dev_list) 7656 { 7657 char linkname[IFNAMSIZ+7]; 7658 7659 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7660 "upper_%s" : "lower_%s", adj_dev->name); 7661 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7662 linkname); 7663 } 7664 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7665 char *name, 7666 struct list_head *dev_list) 7667 { 7668 char linkname[IFNAMSIZ+7]; 7669 7670 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7671 "upper_%s" : "lower_%s", name); 7672 sysfs_remove_link(&(dev->dev.kobj), linkname); 7673 } 7674 7675 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7676 struct net_device *adj_dev, 7677 struct list_head *dev_list) 7678 { 7679 return (dev_list == &dev->adj_list.upper || 7680 dev_list == &dev->adj_list.lower) && 7681 net_eq(dev_net(dev), dev_net(adj_dev)); 7682 } 7683 7684 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7685 struct net_device *adj_dev, 7686 struct list_head *dev_list, 7687 void *private, bool master) 7688 { 7689 struct netdev_adjacent *adj; 7690 int ret; 7691 7692 adj = __netdev_find_adj(adj_dev, dev_list); 7693 7694 if (adj) { 7695 adj->ref_nr += 1; 7696 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7697 dev->name, adj_dev->name, adj->ref_nr); 7698 7699 return 0; 7700 } 7701 7702 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7703 if (!adj) 7704 return -ENOMEM; 7705 7706 adj->dev = adj_dev; 7707 adj->master = master; 7708 adj->ref_nr = 1; 7709 adj->private = private; 7710 adj->ignore = false; 7711 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 7712 7713 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7714 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7715 7716 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7717 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7718 if (ret) 7719 goto free_adj; 7720 } 7721 7722 /* Ensure that master link is always the first item in list. */ 7723 if (master) { 7724 ret = sysfs_create_link(&(dev->dev.kobj), 7725 &(adj_dev->dev.kobj), "master"); 7726 if (ret) 7727 goto remove_symlinks; 7728 7729 list_add_rcu(&adj->list, dev_list); 7730 } else { 7731 list_add_tail_rcu(&adj->list, dev_list); 7732 } 7733 7734 return 0; 7735 7736 remove_symlinks: 7737 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7738 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7739 free_adj: 7740 netdev_put(adj_dev, &adj->dev_tracker); 7741 kfree(adj); 7742 7743 return ret; 7744 } 7745 7746 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7747 struct net_device *adj_dev, 7748 u16 ref_nr, 7749 struct list_head *dev_list) 7750 { 7751 struct netdev_adjacent *adj; 7752 7753 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7754 dev->name, adj_dev->name, ref_nr); 7755 7756 adj = __netdev_find_adj(adj_dev, dev_list); 7757 7758 if (!adj) { 7759 pr_err("Adjacency does not exist for device %s from %s\n", 7760 dev->name, adj_dev->name); 7761 WARN_ON(1); 7762 return; 7763 } 7764 7765 if (adj->ref_nr > ref_nr) { 7766 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7767 dev->name, adj_dev->name, ref_nr, 7768 adj->ref_nr - ref_nr); 7769 adj->ref_nr -= ref_nr; 7770 return; 7771 } 7772 7773 if (adj->master) 7774 sysfs_remove_link(&(dev->dev.kobj), "master"); 7775 7776 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7777 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7778 7779 list_del_rcu(&adj->list); 7780 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7781 adj_dev->name, dev->name, adj_dev->name); 7782 netdev_put(adj_dev, &adj->dev_tracker); 7783 kfree_rcu(adj, rcu); 7784 } 7785 7786 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7787 struct net_device *upper_dev, 7788 struct list_head *up_list, 7789 struct list_head *down_list, 7790 void *private, bool master) 7791 { 7792 int ret; 7793 7794 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7795 private, master); 7796 if (ret) 7797 return ret; 7798 7799 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7800 private, false); 7801 if (ret) { 7802 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7803 return ret; 7804 } 7805 7806 return 0; 7807 } 7808 7809 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7810 struct net_device *upper_dev, 7811 u16 ref_nr, 7812 struct list_head *up_list, 7813 struct list_head *down_list) 7814 { 7815 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7816 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7817 } 7818 7819 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7820 struct net_device *upper_dev, 7821 void *private, bool master) 7822 { 7823 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7824 &dev->adj_list.upper, 7825 &upper_dev->adj_list.lower, 7826 private, master); 7827 } 7828 7829 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7830 struct net_device *upper_dev) 7831 { 7832 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7833 &dev->adj_list.upper, 7834 &upper_dev->adj_list.lower); 7835 } 7836 7837 static int __netdev_upper_dev_link(struct net_device *dev, 7838 struct net_device *upper_dev, bool master, 7839 void *upper_priv, void *upper_info, 7840 struct netdev_nested_priv *priv, 7841 struct netlink_ext_ack *extack) 7842 { 7843 struct netdev_notifier_changeupper_info changeupper_info = { 7844 .info = { 7845 .dev = dev, 7846 .extack = extack, 7847 }, 7848 .upper_dev = upper_dev, 7849 .master = master, 7850 .linking = true, 7851 .upper_info = upper_info, 7852 }; 7853 struct net_device *master_dev; 7854 int ret = 0; 7855 7856 ASSERT_RTNL(); 7857 7858 if (dev == upper_dev) 7859 return -EBUSY; 7860 7861 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7862 if (__netdev_has_upper_dev(upper_dev, dev)) 7863 return -EBUSY; 7864 7865 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7866 return -EMLINK; 7867 7868 if (!master) { 7869 if (__netdev_has_upper_dev(dev, upper_dev)) 7870 return -EEXIST; 7871 } else { 7872 master_dev = __netdev_master_upper_dev_get(dev); 7873 if (master_dev) 7874 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7875 } 7876 7877 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7878 &changeupper_info.info); 7879 ret = notifier_to_errno(ret); 7880 if (ret) 7881 return ret; 7882 7883 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7884 master); 7885 if (ret) 7886 return ret; 7887 7888 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7889 &changeupper_info.info); 7890 ret = notifier_to_errno(ret); 7891 if (ret) 7892 goto rollback; 7893 7894 __netdev_update_upper_level(dev, NULL); 7895 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7896 7897 __netdev_update_lower_level(upper_dev, priv); 7898 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7899 priv); 7900 7901 return 0; 7902 7903 rollback: 7904 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7905 7906 return ret; 7907 } 7908 7909 /** 7910 * netdev_upper_dev_link - Add a link to the upper device 7911 * @dev: device 7912 * @upper_dev: new upper device 7913 * @extack: netlink extended ack 7914 * 7915 * Adds a link to device which is upper to this one. The caller must hold 7916 * the RTNL lock. On a failure a negative errno code is returned. 7917 * On success the reference counts are adjusted and the function 7918 * returns zero. 7919 */ 7920 int netdev_upper_dev_link(struct net_device *dev, 7921 struct net_device *upper_dev, 7922 struct netlink_ext_ack *extack) 7923 { 7924 struct netdev_nested_priv priv = { 7925 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7926 .data = NULL, 7927 }; 7928 7929 return __netdev_upper_dev_link(dev, upper_dev, false, 7930 NULL, NULL, &priv, extack); 7931 } 7932 EXPORT_SYMBOL(netdev_upper_dev_link); 7933 7934 /** 7935 * netdev_master_upper_dev_link - Add a master link to the upper device 7936 * @dev: device 7937 * @upper_dev: new upper device 7938 * @upper_priv: upper device private 7939 * @upper_info: upper info to be passed down via notifier 7940 * @extack: netlink extended ack 7941 * 7942 * Adds a link to device which is upper to this one. In this case, only 7943 * one master upper device can be linked, although other non-master devices 7944 * might be linked as well. The caller must hold the RTNL lock. 7945 * On a failure a negative errno code is returned. On success the reference 7946 * counts are adjusted and the function returns zero. 7947 */ 7948 int netdev_master_upper_dev_link(struct net_device *dev, 7949 struct net_device *upper_dev, 7950 void *upper_priv, void *upper_info, 7951 struct netlink_ext_ack *extack) 7952 { 7953 struct netdev_nested_priv priv = { 7954 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7955 .data = NULL, 7956 }; 7957 7958 return __netdev_upper_dev_link(dev, upper_dev, true, 7959 upper_priv, upper_info, &priv, extack); 7960 } 7961 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7962 7963 static void __netdev_upper_dev_unlink(struct net_device *dev, 7964 struct net_device *upper_dev, 7965 struct netdev_nested_priv *priv) 7966 { 7967 struct netdev_notifier_changeupper_info changeupper_info = { 7968 .info = { 7969 .dev = dev, 7970 }, 7971 .upper_dev = upper_dev, 7972 .linking = false, 7973 }; 7974 7975 ASSERT_RTNL(); 7976 7977 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7978 7979 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7980 &changeupper_info.info); 7981 7982 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7983 7984 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7985 &changeupper_info.info); 7986 7987 __netdev_update_upper_level(dev, NULL); 7988 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7989 7990 __netdev_update_lower_level(upper_dev, priv); 7991 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7992 priv); 7993 } 7994 7995 /** 7996 * netdev_upper_dev_unlink - Removes a link to upper device 7997 * @dev: device 7998 * @upper_dev: new upper device 7999 * 8000 * Removes a link to device which is upper to this one. The caller must hold 8001 * the RTNL lock. 8002 */ 8003 void netdev_upper_dev_unlink(struct net_device *dev, 8004 struct net_device *upper_dev) 8005 { 8006 struct netdev_nested_priv priv = { 8007 .flags = NESTED_SYNC_TODO, 8008 .data = NULL, 8009 }; 8010 8011 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 8012 } 8013 EXPORT_SYMBOL(netdev_upper_dev_unlink); 8014 8015 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 8016 struct net_device *lower_dev, 8017 bool val) 8018 { 8019 struct netdev_adjacent *adj; 8020 8021 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 8022 if (adj) 8023 adj->ignore = val; 8024 8025 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 8026 if (adj) 8027 adj->ignore = val; 8028 } 8029 8030 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 8031 struct net_device *lower_dev) 8032 { 8033 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 8034 } 8035 8036 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 8037 struct net_device *lower_dev) 8038 { 8039 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 8040 } 8041 8042 int netdev_adjacent_change_prepare(struct net_device *old_dev, 8043 struct net_device *new_dev, 8044 struct net_device *dev, 8045 struct netlink_ext_ack *extack) 8046 { 8047 struct netdev_nested_priv priv = { 8048 .flags = 0, 8049 .data = NULL, 8050 }; 8051 int err; 8052 8053 if (!new_dev) 8054 return 0; 8055 8056 if (old_dev && new_dev != old_dev) 8057 netdev_adjacent_dev_disable(dev, old_dev); 8058 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 8059 extack); 8060 if (err) { 8061 if (old_dev && new_dev != old_dev) 8062 netdev_adjacent_dev_enable(dev, old_dev); 8063 return err; 8064 } 8065 8066 return 0; 8067 } 8068 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 8069 8070 void netdev_adjacent_change_commit(struct net_device *old_dev, 8071 struct net_device *new_dev, 8072 struct net_device *dev) 8073 { 8074 struct netdev_nested_priv priv = { 8075 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8076 .data = NULL, 8077 }; 8078 8079 if (!new_dev || !old_dev) 8080 return; 8081 8082 if (new_dev == old_dev) 8083 return; 8084 8085 netdev_adjacent_dev_enable(dev, old_dev); 8086 __netdev_upper_dev_unlink(old_dev, dev, &priv); 8087 } 8088 EXPORT_SYMBOL(netdev_adjacent_change_commit); 8089 8090 void netdev_adjacent_change_abort(struct net_device *old_dev, 8091 struct net_device *new_dev, 8092 struct net_device *dev) 8093 { 8094 struct netdev_nested_priv priv = { 8095 .flags = 0, 8096 .data = NULL, 8097 }; 8098 8099 if (!new_dev) 8100 return; 8101 8102 if (old_dev && new_dev != old_dev) 8103 netdev_adjacent_dev_enable(dev, old_dev); 8104 8105 __netdev_upper_dev_unlink(new_dev, dev, &priv); 8106 } 8107 EXPORT_SYMBOL(netdev_adjacent_change_abort); 8108 8109 /** 8110 * netdev_bonding_info_change - Dispatch event about slave change 8111 * @dev: device 8112 * @bonding_info: info to dispatch 8113 * 8114 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 8115 * The caller must hold the RTNL lock. 8116 */ 8117 void netdev_bonding_info_change(struct net_device *dev, 8118 struct netdev_bonding_info *bonding_info) 8119 { 8120 struct netdev_notifier_bonding_info info = { 8121 .info.dev = dev, 8122 }; 8123 8124 memcpy(&info.bonding_info, bonding_info, 8125 sizeof(struct netdev_bonding_info)); 8126 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 8127 &info.info); 8128 } 8129 EXPORT_SYMBOL(netdev_bonding_info_change); 8130 8131 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 8132 struct netlink_ext_ack *extack) 8133 { 8134 struct netdev_notifier_offload_xstats_info info = { 8135 .info.dev = dev, 8136 .info.extack = extack, 8137 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 8138 }; 8139 int err; 8140 int rc; 8141 8142 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 8143 GFP_KERNEL); 8144 if (!dev->offload_xstats_l3) 8145 return -ENOMEM; 8146 8147 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 8148 NETDEV_OFFLOAD_XSTATS_DISABLE, 8149 &info.info); 8150 err = notifier_to_errno(rc); 8151 if (err) 8152 goto free_stats; 8153 8154 return 0; 8155 8156 free_stats: 8157 kfree(dev->offload_xstats_l3); 8158 dev->offload_xstats_l3 = NULL; 8159 return err; 8160 } 8161 8162 int netdev_offload_xstats_enable(struct net_device *dev, 8163 enum netdev_offload_xstats_type type, 8164 struct netlink_ext_ack *extack) 8165 { 8166 ASSERT_RTNL(); 8167 8168 if (netdev_offload_xstats_enabled(dev, type)) 8169 return -EALREADY; 8170 8171 switch (type) { 8172 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8173 return netdev_offload_xstats_enable_l3(dev, extack); 8174 } 8175 8176 WARN_ON(1); 8177 return -EINVAL; 8178 } 8179 EXPORT_SYMBOL(netdev_offload_xstats_enable); 8180 8181 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 8182 { 8183 struct netdev_notifier_offload_xstats_info info = { 8184 .info.dev = dev, 8185 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 8186 }; 8187 8188 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 8189 &info.info); 8190 kfree(dev->offload_xstats_l3); 8191 dev->offload_xstats_l3 = NULL; 8192 } 8193 8194 int netdev_offload_xstats_disable(struct net_device *dev, 8195 enum netdev_offload_xstats_type type) 8196 { 8197 ASSERT_RTNL(); 8198 8199 if (!netdev_offload_xstats_enabled(dev, type)) 8200 return -EALREADY; 8201 8202 switch (type) { 8203 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8204 netdev_offload_xstats_disable_l3(dev); 8205 return 0; 8206 } 8207 8208 WARN_ON(1); 8209 return -EINVAL; 8210 } 8211 EXPORT_SYMBOL(netdev_offload_xstats_disable); 8212 8213 static void netdev_offload_xstats_disable_all(struct net_device *dev) 8214 { 8215 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 8216 } 8217 8218 static struct rtnl_hw_stats64 * 8219 netdev_offload_xstats_get_ptr(const struct net_device *dev, 8220 enum netdev_offload_xstats_type type) 8221 { 8222 switch (type) { 8223 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8224 return dev->offload_xstats_l3; 8225 } 8226 8227 WARN_ON(1); 8228 return NULL; 8229 } 8230 8231 bool netdev_offload_xstats_enabled(const struct net_device *dev, 8232 enum netdev_offload_xstats_type type) 8233 { 8234 ASSERT_RTNL(); 8235 8236 return netdev_offload_xstats_get_ptr(dev, type); 8237 } 8238 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 8239 8240 struct netdev_notifier_offload_xstats_ru { 8241 bool used; 8242 }; 8243 8244 struct netdev_notifier_offload_xstats_rd { 8245 struct rtnl_hw_stats64 stats; 8246 bool used; 8247 }; 8248 8249 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 8250 const struct rtnl_hw_stats64 *src) 8251 { 8252 dest->rx_packets += src->rx_packets; 8253 dest->tx_packets += src->tx_packets; 8254 dest->rx_bytes += src->rx_bytes; 8255 dest->tx_bytes += src->tx_bytes; 8256 dest->rx_errors += src->rx_errors; 8257 dest->tx_errors += src->tx_errors; 8258 dest->rx_dropped += src->rx_dropped; 8259 dest->tx_dropped += src->tx_dropped; 8260 dest->multicast += src->multicast; 8261 } 8262 8263 static int netdev_offload_xstats_get_used(struct net_device *dev, 8264 enum netdev_offload_xstats_type type, 8265 bool *p_used, 8266 struct netlink_ext_ack *extack) 8267 { 8268 struct netdev_notifier_offload_xstats_ru report_used = {}; 8269 struct netdev_notifier_offload_xstats_info info = { 8270 .info.dev = dev, 8271 .info.extack = extack, 8272 .type = type, 8273 .report_used = &report_used, 8274 }; 8275 int rc; 8276 8277 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8278 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8279 &info.info); 8280 *p_used = report_used.used; 8281 return notifier_to_errno(rc); 8282 } 8283 8284 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8285 enum netdev_offload_xstats_type type, 8286 struct rtnl_hw_stats64 *p_stats, 8287 bool *p_used, 8288 struct netlink_ext_ack *extack) 8289 { 8290 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8291 struct netdev_notifier_offload_xstats_info info = { 8292 .info.dev = dev, 8293 .info.extack = extack, 8294 .type = type, 8295 .report_delta = &report_delta, 8296 }; 8297 struct rtnl_hw_stats64 *stats; 8298 int rc; 8299 8300 stats = netdev_offload_xstats_get_ptr(dev, type); 8301 if (WARN_ON(!stats)) 8302 return -EINVAL; 8303 8304 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8305 &info.info); 8306 8307 /* Cache whatever we got, even if there was an error, otherwise the 8308 * successful stats retrievals would get lost. 8309 */ 8310 netdev_hw_stats64_add(stats, &report_delta.stats); 8311 8312 if (p_stats) 8313 *p_stats = *stats; 8314 *p_used = report_delta.used; 8315 8316 return notifier_to_errno(rc); 8317 } 8318 8319 int netdev_offload_xstats_get(struct net_device *dev, 8320 enum netdev_offload_xstats_type type, 8321 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8322 struct netlink_ext_ack *extack) 8323 { 8324 ASSERT_RTNL(); 8325 8326 if (p_stats) 8327 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8328 p_used, extack); 8329 else 8330 return netdev_offload_xstats_get_used(dev, type, p_used, 8331 extack); 8332 } 8333 EXPORT_SYMBOL(netdev_offload_xstats_get); 8334 8335 void 8336 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8337 const struct rtnl_hw_stats64 *stats) 8338 { 8339 report_delta->used = true; 8340 netdev_hw_stats64_add(&report_delta->stats, stats); 8341 } 8342 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8343 8344 void 8345 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8346 { 8347 report_used->used = true; 8348 } 8349 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8350 8351 void netdev_offload_xstats_push_delta(struct net_device *dev, 8352 enum netdev_offload_xstats_type type, 8353 const struct rtnl_hw_stats64 *p_stats) 8354 { 8355 struct rtnl_hw_stats64 *stats; 8356 8357 ASSERT_RTNL(); 8358 8359 stats = netdev_offload_xstats_get_ptr(dev, type); 8360 if (WARN_ON(!stats)) 8361 return; 8362 8363 netdev_hw_stats64_add(stats, p_stats); 8364 } 8365 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8366 8367 /** 8368 * netdev_get_xmit_slave - Get the xmit slave of master device 8369 * @dev: device 8370 * @skb: The packet 8371 * @all_slaves: assume all the slaves are active 8372 * 8373 * The reference counters are not incremented so the caller must be 8374 * careful with locks. The caller must hold RCU lock. 8375 * %NULL is returned if no slave is found. 8376 */ 8377 8378 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8379 struct sk_buff *skb, 8380 bool all_slaves) 8381 { 8382 const struct net_device_ops *ops = dev->netdev_ops; 8383 8384 if (!ops->ndo_get_xmit_slave) 8385 return NULL; 8386 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8387 } 8388 EXPORT_SYMBOL(netdev_get_xmit_slave); 8389 8390 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8391 struct sock *sk) 8392 { 8393 const struct net_device_ops *ops = dev->netdev_ops; 8394 8395 if (!ops->ndo_sk_get_lower_dev) 8396 return NULL; 8397 return ops->ndo_sk_get_lower_dev(dev, sk); 8398 } 8399 8400 /** 8401 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8402 * @dev: device 8403 * @sk: the socket 8404 * 8405 * %NULL is returned if no lower device is found. 8406 */ 8407 8408 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8409 struct sock *sk) 8410 { 8411 struct net_device *lower; 8412 8413 lower = netdev_sk_get_lower_dev(dev, sk); 8414 while (lower) { 8415 dev = lower; 8416 lower = netdev_sk_get_lower_dev(dev, sk); 8417 } 8418 8419 return dev; 8420 } 8421 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8422 8423 static void netdev_adjacent_add_links(struct net_device *dev) 8424 { 8425 struct netdev_adjacent *iter; 8426 8427 struct net *net = dev_net(dev); 8428 8429 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8430 if (!net_eq(net, dev_net(iter->dev))) 8431 continue; 8432 netdev_adjacent_sysfs_add(iter->dev, dev, 8433 &iter->dev->adj_list.lower); 8434 netdev_adjacent_sysfs_add(dev, iter->dev, 8435 &dev->adj_list.upper); 8436 } 8437 8438 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8439 if (!net_eq(net, dev_net(iter->dev))) 8440 continue; 8441 netdev_adjacent_sysfs_add(iter->dev, dev, 8442 &iter->dev->adj_list.upper); 8443 netdev_adjacent_sysfs_add(dev, iter->dev, 8444 &dev->adj_list.lower); 8445 } 8446 } 8447 8448 static void netdev_adjacent_del_links(struct net_device *dev) 8449 { 8450 struct netdev_adjacent *iter; 8451 8452 struct net *net = dev_net(dev); 8453 8454 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8455 if (!net_eq(net, dev_net(iter->dev))) 8456 continue; 8457 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8458 &iter->dev->adj_list.lower); 8459 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8460 &dev->adj_list.upper); 8461 } 8462 8463 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8464 if (!net_eq(net, dev_net(iter->dev))) 8465 continue; 8466 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8467 &iter->dev->adj_list.upper); 8468 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8469 &dev->adj_list.lower); 8470 } 8471 } 8472 8473 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8474 { 8475 struct netdev_adjacent *iter; 8476 8477 struct net *net = dev_net(dev); 8478 8479 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8480 if (!net_eq(net, dev_net(iter->dev))) 8481 continue; 8482 netdev_adjacent_sysfs_del(iter->dev, oldname, 8483 &iter->dev->adj_list.lower); 8484 netdev_adjacent_sysfs_add(iter->dev, dev, 8485 &iter->dev->adj_list.lower); 8486 } 8487 8488 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8489 if (!net_eq(net, dev_net(iter->dev))) 8490 continue; 8491 netdev_adjacent_sysfs_del(iter->dev, oldname, 8492 &iter->dev->adj_list.upper); 8493 netdev_adjacent_sysfs_add(iter->dev, dev, 8494 &iter->dev->adj_list.upper); 8495 } 8496 } 8497 8498 void *netdev_lower_dev_get_private(struct net_device *dev, 8499 struct net_device *lower_dev) 8500 { 8501 struct netdev_adjacent *lower; 8502 8503 if (!lower_dev) 8504 return NULL; 8505 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8506 if (!lower) 8507 return NULL; 8508 8509 return lower->private; 8510 } 8511 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8512 8513 8514 /** 8515 * netdev_lower_state_changed - Dispatch event about lower device state change 8516 * @lower_dev: device 8517 * @lower_state_info: state to dispatch 8518 * 8519 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8520 * The caller must hold the RTNL lock. 8521 */ 8522 void netdev_lower_state_changed(struct net_device *lower_dev, 8523 void *lower_state_info) 8524 { 8525 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 8526 .info.dev = lower_dev, 8527 }; 8528 8529 ASSERT_RTNL(); 8530 changelowerstate_info.lower_state_info = lower_state_info; 8531 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 8532 &changelowerstate_info.info); 8533 } 8534 EXPORT_SYMBOL(netdev_lower_state_changed); 8535 8536 static void dev_change_rx_flags(struct net_device *dev, int flags) 8537 { 8538 const struct net_device_ops *ops = dev->netdev_ops; 8539 8540 if (ops->ndo_change_rx_flags) 8541 ops->ndo_change_rx_flags(dev, flags); 8542 } 8543 8544 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 8545 { 8546 unsigned int old_flags = dev->flags; 8547 unsigned int promiscuity, flags; 8548 kuid_t uid; 8549 kgid_t gid; 8550 8551 ASSERT_RTNL(); 8552 8553 promiscuity = dev->promiscuity + inc; 8554 if (promiscuity == 0) { 8555 /* 8556 * Avoid overflow. 8557 * If inc causes overflow, untouch promisc and return error. 8558 */ 8559 if (unlikely(inc > 0)) { 8560 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 8561 return -EOVERFLOW; 8562 } 8563 flags = old_flags & ~IFF_PROMISC; 8564 } else { 8565 flags = old_flags | IFF_PROMISC; 8566 } 8567 WRITE_ONCE(dev->promiscuity, promiscuity); 8568 if (flags != old_flags) { 8569 WRITE_ONCE(dev->flags, flags); 8570 netdev_info(dev, "%s promiscuous mode\n", 8571 dev->flags & IFF_PROMISC ? "entered" : "left"); 8572 if (audit_enabled) { 8573 current_uid_gid(&uid, &gid); 8574 audit_log(audit_context(), GFP_ATOMIC, 8575 AUDIT_ANOM_PROMISCUOUS, 8576 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 8577 dev->name, (dev->flags & IFF_PROMISC), 8578 (old_flags & IFF_PROMISC), 8579 from_kuid(&init_user_ns, audit_get_loginuid(current)), 8580 from_kuid(&init_user_ns, uid), 8581 from_kgid(&init_user_ns, gid), 8582 audit_get_sessionid(current)); 8583 } 8584 8585 dev_change_rx_flags(dev, IFF_PROMISC); 8586 } 8587 if (notify) 8588 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 8589 return 0; 8590 } 8591 8592 /** 8593 * dev_set_promiscuity - update promiscuity count on a device 8594 * @dev: device 8595 * @inc: modifier 8596 * 8597 * Add or remove promiscuity from a device. While the count in the device 8598 * remains above zero the interface remains promiscuous. Once it hits zero 8599 * the device reverts back to normal filtering operation. A negative inc 8600 * value is used to drop promiscuity on the device. 8601 * Return 0 if successful or a negative errno code on error. 8602 */ 8603 int dev_set_promiscuity(struct net_device *dev, int inc) 8604 { 8605 unsigned int old_flags = dev->flags; 8606 int err; 8607 8608 err = __dev_set_promiscuity(dev, inc, true); 8609 if (err < 0) 8610 return err; 8611 if (dev->flags != old_flags) 8612 dev_set_rx_mode(dev); 8613 return err; 8614 } 8615 EXPORT_SYMBOL(dev_set_promiscuity); 8616 8617 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 8618 { 8619 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 8620 unsigned int allmulti, flags; 8621 8622 ASSERT_RTNL(); 8623 8624 allmulti = dev->allmulti + inc; 8625 if (allmulti == 0) { 8626 /* 8627 * Avoid overflow. 8628 * If inc causes overflow, untouch allmulti and return error. 8629 */ 8630 if (unlikely(inc > 0)) { 8631 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 8632 return -EOVERFLOW; 8633 } 8634 flags = old_flags & ~IFF_ALLMULTI; 8635 } else { 8636 flags = old_flags | IFF_ALLMULTI; 8637 } 8638 WRITE_ONCE(dev->allmulti, allmulti); 8639 if (flags != old_flags) { 8640 WRITE_ONCE(dev->flags, flags); 8641 netdev_info(dev, "%s allmulticast mode\n", 8642 dev->flags & IFF_ALLMULTI ? "entered" : "left"); 8643 dev_change_rx_flags(dev, IFF_ALLMULTI); 8644 dev_set_rx_mode(dev); 8645 if (notify) 8646 __dev_notify_flags(dev, old_flags, 8647 dev->gflags ^ old_gflags, 0, NULL); 8648 } 8649 return 0; 8650 } 8651 8652 /** 8653 * dev_set_allmulti - update allmulti count on a device 8654 * @dev: device 8655 * @inc: modifier 8656 * 8657 * Add or remove reception of all multicast frames to a device. While the 8658 * count in the device remains above zero the interface remains listening 8659 * to all interfaces. Once it hits zero the device reverts back to normal 8660 * filtering operation. A negative @inc value is used to drop the counter 8661 * when releasing a resource needing all multicasts. 8662 * Return 0 if successful or a negative errno code on error. 8663 */ 8664 8665 int dev_set_allmulti(struct net_device *dev, int inc) 8666 { 8667 return __dev_set_allmulti(dev, inc, true); 8668 } 8669 EXPORT_SYMBOL(dev_set_allmulti); 8670 8671 /* 8672 * Upload unicast and multicast address lists to device and 8673 * configure RX filtering. When the device doesn't support unicast 8674 * filtering it is put in promiscuous mode while unicast addresses 8675 * are present. 8676 */ 8677 void __dev_set_rx_mode(struct net_device *dev) 8678 { 8679 const struct net_device_ops *ops = dev->netdev_ops; 8680 8681 /* dev_open will call this function so the list will stay sane. */ 8682 if (!(dev->flags&IFF_UP)) 8683 return; 8684 8685 if (!netif_device_present(dev)) 8686 return; 8687 8688 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8689 /* Unicast addresses changes may only happen under the rtnl, 8690 * therefore calling __dev_set_promiscuity here is safe. 8691 */ 8692 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8693 __dev_set_promiscuity(dev, 1, false); 8694 dev->uc_promisc = true; 8695 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8696 __dev_set_promiscuity(dev, -1, false); 8697 dev->uc_promisc = false; 8698 } 8699 } 8700 8701 if (ops->ndo_set_rx_mode) 8702 ops->ndo_set_rx_mode(dev); 8703 } 8704 8705 void dev_set_rx_mode(struct net_device *dev) 8706 { 8707 netif_addr_lock_bh(dev); 8708 __dev_set_rx_mode(dev); 8709 netif_addr_unlock_bh(dev); 8710 } 8711 8712 /** 8713 * dev_get_flags - get flags reported to userspace 8714 * @dev: device 8715 * 8716 * Get the combination of flag bits exported through APIs to userspace. 8717 */ 8718 unsigned int dev_get_flags(const struct net_device *dev) 8719 { 8720 unsigned int flags; 8721 8722 flags = (READ_ONCE(dev->flags) & ~(IFF_PROMISC | 8723 IFF_ALLMULTI | 8724 IFF_RUNNING | 8725 IFF_LOWER_UP | 8726 IFF_DORMANT)) | 8727 (READ_ONCE(dev->gflags) & (IFF_PROMISC | 8728 IFF_ALLMULTI)); 8729 8730 if (netif_running(dev)) { 8731 if (netif_oper_up(dev)) 8732 flags |= IFF_RUNNING; 8733 if (netif_carrier_ok(dev)) 8734 flags |= IFF_LOWER_UP; 8735 if (netif_dormant(dev)) 8736 flags |= IFF_DORMANT; 8737 } 8738 8739 return flags; 8740 } 8741 EXPORT_SYMBOL(dev_get_flags); 8742 8743 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8744 struct netlink_ext_ack *extack) 8745 { 8746 unsigned int old_flags = dev->flags; 8747 int ret; 8748 8749 ASSERT_RTNL(); 8750 8751 /* 8752 * Set the flags on our device. 8753 */ 8754 8755 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8756 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8757 IFF_AUTOMEDIA)) | 8758 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8759 IFF_ALLMULTI)); 8760 8761 /* 8762 * Load in the correct multicast list now the flags have changed. 8763 */ 8764 8765 if ((old_flags ^ flags) & IFF_MULTICAST) 8766 dev_change_rx_flags(dev, IFF_MULTICAST); 8767 8768 dev_set_rx_mode(dev); 8769 8770 /* 8771 * Have we downed the interface. We handle IFF_UP ourselves 8772 * according to user attempts to set it, rather than blindly 8773 * setting it. 8774 */ 8775 8776 ret = 0; 8777 if ((old_flags ^ flags) & IFF_UP) { 8778 if (old_flags & IFF_UP) 8779 __dev_close(dev); 8780 else 8781 ret = __dev_open(dev, extack); 8782 } 8783 8784 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8785 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8786 unsigned int old_flags = dev->flags; 8787 8788 dev->gflags ^= IFF_PROMISC; 8789 8790 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8791 if (dev->flags != old_flags) 8792 dev_set_rx_mode(dev); 8793 } 8794 8795 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8796 * is important. Some (broken) drivers set IFF_PROMISC, when 8797 * IFF_ALLMULTI is requested not asking us and not reporting. 8798 */ 8799 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8800 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8801 8802 dev->gflags ^= IFF_ALLMULTI; 8803 __dev_set_allmulti(dev, inc, false); 8804 } 8805 8806 return ret; 8807 } 8808 8809 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8810 unsigned int gchanges, u32 portid, 8811 const struct nlmsghdr *nlh) 8812 { 8813 unsigned int changes = dev->flags ^ old_flags; 8814 8815 if (gchanges) 8816 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 8817 8818 if (changes & IFF_UP) { 8819 if (dev->flags & IFF_UP) 8820 call_netdevice_notifiers(NETDEV_UP, dev); 8821 else 8822 call_netdevice_notifiers(NETDEV_DOWN, dev); 8823 } 8824 8825 if (dev->flags & IFF_UP && 8826 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8827 struct netdev_notifier_change_info change_info = { 8828 .info = { 8829 .dev = dev, 8830 }, 8831 .flags_changed = changes, 8832 }; 8833 8834 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8835 } 8836 } 8837 8838 /** 8839 * dev_change_flags - change device settings 8840 * @dev: device 8841 * @flags: device state flags 8842 * @extack: netlink extended ack 8843 * 8844 * Change settings on device based state flags. The flags are 8845 * in the userspace exported format. 8846 */ 8847 int dev_change_flags(struct net_device *dev, unsigned int flags, 8848 struct netlink_ext_ack *extack) 8849 { 8850 int ret; 8851 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8852 8853 ret = __dev_change_flags(dev, flags, extack); 8854 if (ret < 0) 8855 return ret; 8856 8857 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8858 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 8859 return ret; 8860 } 8861 EXPORT_SYMBOL(dev_change_flags); 8862 8863 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8864 { 8865 const struct net_device_ops *ops = dev->netdev_ops; 8866 8867 if (ops->ndo_change_mtu) 8868 return ops->ndo_change_mtu(dev, new_mtu); 8869 8870 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8871 WRITE_ONCE(dev->mtu, new_mtu); 8872 return 0; 8873 } 8874 EXPORT_SYMBOL(__dev_set_mtu); 8875 8876 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8877 struct netlink_ext_ack *extack) 8878 { 8879 /* MTU must be positive, and in range */ 8880 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8881 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8882 return -EINVAL; 8883 } 8884 8885 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8886 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8887 return -EINVAL; 8888 } 8889 return 0; 8890 } 8891 8892 /** 8893 * dev_set_mtu_ext - Change maximum transfer unit 8894 * @dev: device 8895 * @new_mtu: new transfer unit 8896 * @extack: netlink extended ack 8897 * 8898 * Change the maximum transfer size of the network device. 8899 */ 8900 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8901 struct netlink_ext_ack *extack) 8902 { 8903 int err, orig_mtu; 8904 8905 if (new_mtu == dev->mtu) 8906 return 0; 8907 8908 err = dev_validate_mtu(dev, new_mtu, extack); 8909 if (err) 8910 return err; 8911 8912 if (!netif_device_present(dev)) 8913 return -ENODEV; 8914 8915 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8916 err = notifier_to_errno(err); 8917 if (err) 8918 return err; 8919 8920 orig_mtu = dev->mtu; 8921 err = __dev_set_mtu(dev, new_mtu); 8922 8923 if (!err) { 8924 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8925 orig_mtu); 8926 err = notifier_to_errno(err); 8927 if (err) { 8928 /* setting mtu back and notifying everyone again, 8929 * so that they have a chance to revert changes. 8930 */ 8931 __dev_set_mtu(dev, orig_mtu); 8932 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8933 new_mtu); 8934 } 8935 } 8936 return err; 8937 } 8938 8939 int dev_set_mtu(struct net_device *dev, int new_mtu) 8940 { 8941 struct netlink_ext_ack extack; 8942 int err; 8943 8944 memset(&extack, 0, sizeof(extack)); 8945 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8946 if (err && extack._msg) 8947 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8948 return err; 8949 } 8950 EXPORT_SYMBOL(dev_set_mtu); 8951 8952 /** 8953 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8954 * @dev: device 8955 * @new_len: new tx queue length 8956 */ 8957 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8958 { 8959 unsigned int orig_len = dev->tx_queue_len; 8960 int res; 8961 8962 if (new_len != (unsigned int)new_len) 8963 return -ERANGE; 8964 8965 if (new_len != orig_len) { 8966 WRITE_ONCE(dev->tx_queue_len, new_len); 8967 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8968 res = notifier_to_errno(res); 8969 if (res) 8970 goto err_rollback; 8971 res = dev_qdisc_change_tx_queue_len(dev); 8972 if (res) 8973 goto err_rollback; 8974 } 8975 8976 return 0; 8977 8978 err_rollback: 8979 netdev_err(dev, "refused to change device tx_queue_len\n"); 8980 WRITE_ONCE(dev->tx_queue_len, orig_len); 8981 return res; 8982 } 8983 8984 /** 8985 * dev_set_group - Change group this device belongs to 8986 * @dev: device 8987 * @new_group: group this device should belong to 8988 */ 8989 void dev_set_group(struct net_device *dev, int new_group) 8990 { 8991 dev->group = new_group; 8992 } 8993 8994 /** 8995 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8996 * @dev: device 8997 * @addr: new address 8998 * @extack: netlink extended ack 8999 */ 9000 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 9001 struct netlink_ext_ack *extack) 9002 { 9003 struct netdev_notifier_pre_changeaddr_info info = { 9004 .info.dev = dev, 9005 .info.extack = extack, 9006 .dev_addr = addr, 9007 }; 9008 int rc; 9009 9010 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 9011 return notifier_to_errno(rc); 9012 } 9013 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 9014 9015 /** 9016 * dev_set_mac_address - Change Media Access Control Address 9017 * @dev: device 9018 * @sa: new address 9019 * @extack: netlink extended ack 9020 * 9021 * Change the hardware (MAC) address of the device 9022 */ 9023 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 9024 struct netlink_ext_ack *extack) 9025 { 9026 const struct net_device_ops *ops = dev->netdev_ops; 9027 int err; 9028 9029 if (!ops->ndo_set_mac_address) 9030 return -EOPNOTSUPP; 9031 if (sa->sa_family != dev->type) 9032 return -EINVAL; 9033 if (!netif_device_present(dev)) 9034 return -ENODEV; 9035 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 9036 if (err) 9037 return err; 9038 if (memcmp(dev->dev_addr, sa->sa_data, dev->addr_len)) { 9039 err = ops->ndo_set_mac_address(dev, sa); 9040 if (err) 9041 return err; 9042 } 9043 dev->addr_assign_type = NET_ADDR_SET; 9044 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 9045 add_device_randomness(dev->dev_addr, dev->addr_len); 9046 return 0; 9047 } 9048 EXPORT_SYMBOL(dev_set_mac_address); 9049 9050 DECLARE_RWSEM(dev_addr_sem); 9051 9052 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 9053 struct netlink_ext_ack *extack) 9054 { 9055 int ret; 9056 9057 down_write(&dev_addr_sem); 9058 ret = dev_set_mac_address(dev, sa, extack); 9059 up_write(&dev_addr_sem); 9060 return ret; 9061 } 9062 EXPORT_SYMBOL(dev_set_mac_address_user); 9063 9064 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 9065 { 9066 size_t size = sizeof(sa->sa_data_min); 9067 struct net_device *dev; 9068 int ret = 0; 9069 9070 down_read(&dev_addr_sem); 9071 rcu_read_lock(); 9072 9073 dev = dev_get_by_name_rcu(net, dev_name); 9074 if (!dev) { 9075 ret = -ENODEV; 9076 goto unlock; 9077 } 9078 if (!dev->addr_len) 9079 memset(sa->sa_data, 0, size); 9080 else 9081 memcpy(sa->sa_data, dev->dev_addr, 9082 min_t(size_t, size, dev->addr_len)); 9083 sa->sa_family = dev->type; 9084 9085 unlock: 9086 rcu_read_unlock(); 9087 up_read(&dev_addr_sem); 9088 return ret; 9089 } 9090 EXPORT_SYMBOL(dev_get_mac_address); 9091 9092 /** 9093 * dev_change_carrier - Change device carrier 9094 * @dev: device 9095 * @new_carrier: new value 9096 * 9097 * Change device carrier 9098 */ 9099 int dev_change_carrier(struct net_device *dev, bool new_carrier) 9100 { 9101 const struct net_device_ops *ops = dev->netdev_ops; 9102 9103 if (!ops->ndo_change_carrier) 9104 return -EOPNOTSUPP; 9105 if (!netif_device_present(dev)) 9106 return -ENODEV; 9107 return ops->ndo_change_carrier(dev, new_carrier); 9108 } 9109 9110 /** 9111 * dev_get_phys_port_id - Get device physical port ID 9112 * @dev: device 9113 * @ppid: port ID 9114 * 9115 * Get device physical port ID 9116 */ 9117 int dev_get_phys_port_id(struct net_device *dev, 9118 struct netdev_phys_item_id *ppid) 9119 { 9120 const struct net_device_ops *ops = dev->netdev_ops; 9121 9122 if (!ops->ndo_get_phys_port_id) 9123 return -EOPNOTSUPP; 9124 return ops->ndo_get_phys_port_id(dev, ppid); 9125 } 9126 9127 /** 9128 * dev_get_phys_port_name - Get device physical port name 9129 * @dev: device 9130 * @name: port name 9131 * @len: limit of bytes to copy to name 9132 * 9133 * Get device physical port name 9134 */ 9135 int dev_get_phys_port_name(struct net_device *dev, 9136 char *name, size_t len) 9137 { 9138 const struct net_device_ops *ops = dev->netdev_ops; 9139 int err; 9140 9141 if (ops->ndo_get_phys_port_name) { 9142 err = ops->ndo_get_phys_port_name(dev, name, len); 9143 if (err != -EOPNOTSUPP) 9144 return err; 9145 } 9146 return devlink_compat_phys_port_name_get(dev, name, len); 9147 } 9148 9149 /** 9150 * dev_get_port_parent_id - Get the device's port parent identifier 9151 * @dev: network device 9152 * @ppid: pointer to a storage for the port's parent identifier 9153 * @recurse: allow/disallow recursion to lower devices 9154 * 9155 * Get the devices's port parent identifier 9156 */ 9157 int dev_get_port_parent_id(struct net_device *dev, 9158 struct netdev_phys_item_id *ppid, 9159 bool recurse) 9160 { 9161 const struct net_device_ops *ops = dev->netdev_ops; 9162 struct netdev_phys_item_id first = { }; 9163 struct net_device *lower_dev; 9164 struct list_head *iter; 9165 int err; 9166 9167 if (ops->ndo_get_port_parent_id) { 9168 err = ops->ndo_get_port_parent_id(dev, ppid); 9169 if (err != -EOPNOTSUPP) 9170 return err; 9171 } 9172 9173 err = devlink_compat_switch_id_get(dev, ppid); 9174 if (!recurse || err != -EOPNOTSUPP) 9175 return err; 9176 9177 netdev_for_each_lower_dev(dev, lower_dev, iter) { 9178 err = dev_get_port_parent_id(lower_dev, ppid, true); 9179 if (err) 9180 break; 9181 if (!first.id_len) 9182 first = *ppid; 9183 else if (memcmp(&first, ppid, sizeof(*ppid))) 9184 return -EOPNOTSUPP; 9185 } 9186 9187 return err; 9188 } 9189 EXPORT_SYMBOL(dev_get_port_parent_id); 9190 9191 /** 9192 * netdev_port_same_parent_id - Indicate if two network devices have 9193 * the same port parent identifier 9194 * @a: first network device 9195 * @b: second network device 9196 */ 9197 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 9198 { 9199 struct netdev_phys_item_id a_id = { }; 9200 struct netdev_phys_item_id b_id = { }; 9201 9202 if (dev_get_port_parent_id(a, &a_id, true) || 9203 dev_get_port_parent_id(b, &b_id, true)) 9204 return false; 9205 9206 return netdev_phys_item_id_same(&a_id, &b_id); 9207 } 9208 EXPORT_SYMBOL(netdev_port_same_parent_id); 9209 9210 /** 9211 * dev_change_proto_down - set carrier according to proto_down. 9212 * 9213 * @dev: device 9214 * @proto_down: new value 9215 */ 9216 int dev_change_proto_down(struct net_device *dev, bool proto_down) 9217 { 9218 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN)) 9219 return -EOPNOTSUPP; 9220 if (!netif_device_present(dev)) 9221 return -ENODEV; 9222 if (proto_down) 9223 netif_carrier_off(dev); 9224 else 9225 netif_carrier_on(dev); 9226 WRITE_ONCE(dev->proto_down, proto_down); 9227 return 0; 9228 } 9229 9230 /** 9231 * dev_change_proto_down_reason - proto down reason 9232 * 9233 * @dev: device 9234 * @mask: proto down mask 9235 * @value: proto down value 9236 */ 9237 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 9238 u32 value) 9239 { 9240 u32 proto_down_reason; 9241 int b; 9242 9243 if (!mask) { 9244 proto_down_reason = value; 9245 } else { 9246 proto_down_reason = dev->proto_down_reason; 9247 for_each_set_bit(b, &mask, 32) { 9248 if (value & (1 << b)) 9249 proto_down_reason |= BIT(b); 9250 else 9251 proto_down_reason &= ~BIT(b); 9252 } 9253 } 9254 WRITE_ONCE(dev->proto_down_reason, proto_down_reason); 9255 } 9256 9257 struct bpf_xdp_link { 9258 struct bpf_link link; 9259 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 9260 int flags; 9261 }; 9262 9263 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 9264 { 9265 if (flags & XDP_FLAGS_HW_MODE) 9266 return XDP_MODE_HW; 9267 if (flags & XDP_FLAGS_DRV_MODE) 9268 return XDP_MODE_DRV; 9269 if (flags & XDP_FLAGS_SKB_MODE) 9270 return XDP_MODE_SKB; 9271 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 9272 } 9273 9274 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 9275 { 9276 switch (mode) { 9277 case XDP_MODE_SKB: 9278 return generic_xdp_install; 9279 case XDP_MODE_DRV: 9280 case XDP_MODE_HW: 9281 return dev->netdev_ops->ndo_bpf; 9282 default: 9283 return NULL; 9284 } 9285 } 9286 9287 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9288 enum bpf_xdp_mode mode) 9289 { 9290 return dev->xdp_state[mode].link; 9291 } 9292 9293 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9294 enum bpf_xdp_mode mode) 9295 { 9296 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9297 9298 if (link) 9299 return link->link.prog; 9300 return dev->xdp_state[mode].prog; 9301 } 9302 9303 u8 dev_xdp_prog_count(struct net_device *dev) 9304 { 9305 u8 count = 0; 9306 int i; 9307 9308 for (i = 0; i < __MAX_XDP_MODE; i++) 9309 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9310 count++; 9311 return count; 9312 } 9313 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9314 9315 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9316 { 9317 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9318 9319 return prog ? prog->aux->id : 0; 9320 } 9321 9322 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9323 struct bpf_xdp_link *link) 9324 { 9325 dev->xdp_state[mode].link = link; 9326 dev->xdp_state[mode].prog = NULL; 9327 } 9328 9329 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9330 struct bpf_prog *prog) 9331 { 9332 dev->xdp_state[mode].link = NULL; 9333 dev->xdp_state[mode].prog = prog; 9334 } 9335 9336 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9337 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9338 u32 flags, struct bpf_prog *prog) 9339 { 9340 struct netdev_bpf xdp; 9341 int err; 9342 9343 memset(&xdp, 0, sizeof(xdp)); 9344 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9345 xdp.extack = extack; 9346 xdp.flags = flags; 9347 xdp.prog = prog; 9348 9349 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9350 * "moved" into driver), so they don't increment it on their own, but 9351 * they do decrement refcnt when program is detached or replaced. 9352 * Given net_device also owns link/prog, we need to bump refcnt here 9353 * to prevent drivers from underflowing it. 9354 */ 9355 if (prog) 9356 bpf_prog_inc(prog); 9357 err = bpf_op(dev, &xdp); 9358 if (err) { 9359 if (prog) 9360 bpf_prog_put(prog); 9361 return err; 9362 } 9363 9364 if (mode != XDP_MODE_HW) 9365 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9366 9367 return 0; 9368 } 9369 9370 static void dev_xdp_uninstall(struct net_device *dev) 9371 { 9372 struct bpf_xdp_link *link; 9373 struct bpf_prog *prog; 9374 enum bpf_xdp_mode mode; 9375 bpf_op_t bpf_op; 9376 9377 ASSERT_RTNL(); 9378 9379 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9380 prog = dev_xdp_prog(dev, mode); 9381 if (!prog) 9382 continue; 9383 9384 bpf_op = dev_xdp_bpf_op(dev, mode); 9385 if (!bpf_op) 9386 continue; 9387 9388 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9389 9390 /* auto-detach link from net device */ 9391 link = dev_xdp_link(dev, mode); 9392 if (link) 9393 link->dev = NULL; 9394 else 9395 bpf_prog_put(prog); 9396 9397 dev_xdp_set_link(dev, mode, NULL); 9398 } 9399 } 9400 9401 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9402 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9403 struct bpf_prog *old_prog, u32 flags) 9404 { 9405 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9406 struct bpf_prog *cur_prog; 9407 struct net_device *upper; 9408 struct list_head *iter; 9409 enum bpf_xdp_mode mode; 9410 bpf_op_t bpf_op; 9411 int err; 9412 9413 ASSERT_RTNL(); 9414 9415 /* either link or prog attachment, never both */ 9416 if (link && (new_prog || old_prog)) 9417 return -EINVAL; 9418 /* link supports only XDP mode flags */ 9419 if (link && (flags & ~XDP_FLAGS_MODES)) { 9420 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9421 return -EINVAL; 9422 } 9423 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9424 if (num_modes > 1) { 9425 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9426 return -EINVAL; 9427 } 9428 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9429 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9430 NL_SET_ERR_MSG(extack, 9431 "More than one program loaded, unset mode is ambiguous"); 9432 return -EINVAL; 9433 } 9434 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9435 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9436 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9437 return -EINVAL; 9438 } 9439 9440 mode = dev_xdp_mode(dev, flags); 9441 /* can't replace attached link */ 9442 if (dev_xdp_link(dev, mode)) { 9443 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9444 return -EBUSY; 9445 } 9446 9447 /* don't allow if an upper device already has a program */ 9448 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9449 if (dev_xdp_prog_count(upper) > 0) { 9450 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9451 return -EEXIST; 9452 } 9453 } 9454 9455 cur_prog = dev_xdp_prog(dev, mode); 9456 /* can't replace attached prog with link */ 9457 if (link && cur_prog) { 9458 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9459 return -EBUSY; 9460 } 9461 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9462 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9463 return -EEXIST; 9464 } 9465 9466 /* put effective new program into new_prog */ 9467 if (link) 9468 new_prog = link->link.prog; 9469 9470 if (new_prog) { 9471 bool offload = mode == XDP_MODE_HW; 9472 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9473 ? XDP_MODE_DRV : XDP_MODE_SKB; 9474 9475 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9476 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9477 return -EBUSY; 9478 } 9479 if (!offload && dev_xdp_prog(dev, other_mode)) { 9480 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 9481 return -EEXIST; 9482 } 9483 if (!offload && bpf_prog_is_offloaded(new_prog->aux)) { 9484 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported"); 9485 return -EINVAL; 9486 } 9487 if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) { 9488 NL_SET_ERR_MSG(extack, "Program bound to different device"); 9489 return -EINVAL; 9490 } 9491 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 9492 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 9493 return -EINVAL; 9494 } 9495 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 9496 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 9497 return -EINVAL; 9498 } 9499 } 9500 9501 /* don't call drivers if the effective program didn't change */ 9502 if (new_prog != cur_prog) { 9503 bpf_op = dev_xdp_bpf_op(dev, mode); 9504 if (!bpf_op) { 9505 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 9506 return -EOPNOTSUPP; 9507 } 9508 9509 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 9510 if (err) 9511 return err; 9512 } 9513 9514 if (link) 9515 dev_xdp_set_link(dev, mode, link); 9516 else 9517 dev_xdp_set_prog(dev, mode, new_prog); 9518 if (cur_prog) 9519 bpf_prog_put(cur_prog); 9520 9521 return 0; 9522 } 9523 9524 static int dev_xdp_attach_link(struct net_device *dev, 9525 struct netlink_ext_ack *extack, 9526 struct bpf_xdp_link *link) 9527 { 9528 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 9529 } 9530 9531 static int dev_xdp_detach_link(struct net_device *dev, 9532 struct netlink_ext_ack *extack, 9533 struct bpf_xdp_link *link) 9534 { 9535 enum bpf_xdp_mode mode; 9536 bpf_op_t bpf_op; 9537 9538 ASSERT_RTNL(); 9539 9540 mode = dev_xdp_mode(dev, link->flags); 9541 if (dev_xdp_link(dev, mode) != link) 9542 return -EINVAL; 9543 9544 bpf_op = dev_xdp_bpf_op(dev, mode); 9545 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9546 dev_xdp_set_link(dev, mode, NULL); 9547 return 0; 9548 } 9549 9550 static void bpf_xdp_link_release(struct bpf_link *link) 9551 { 9552 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9553 9554 rtnl_lock(); 9555 9556 /* if racing with net_device's tear down, xdp_link->dev might be 9557 * already NULL, in which case link was already auto-detached 9558 */ 9559 if (xdp_link->dev) { 9560 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 9561 xdp_link->dev = NULL; 9562 } 9563 9564 rtnl_unlock(); 9565 } 9566 9567 static int bpf_xdp_link_detach(struct bpf_link *link) 9568 { 9569 bpf_xdp_link_release(link); 9570 return 0; 9571 } 9572 9573 static void bpf_xdp_link_dealloc(struct bpf_link *link) 9574 { 9575 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9576 9577 kfree(xdp_link); 9578 } 9579 9580 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 9581 struct seq_file *seq) 9582 { 9583 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9584 u32 ifindex = 0; 9585 9586 rtnl_lock(); 9587 if (xdp_link->dev) 9588 ifindex = xdp_link->dev->ifindex; 9589 rtnl_unlock(); 9590 9591 seq_printf(seq, "ifindex:\t%u\n", ifindex); 9592 } 9593 9594 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 9595 struct bpf_link_info *info) 9596 { 9597 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9598 u32 ifindex = 0; 9599 9600 rtnl_lock(); 9601 if (xdp_link->dev) 9602 ifindex = xdp_link->dev->ifindex; 9603 rtnl_unlock(); 9604 9605 info->xdp.ifindex = ifindex; 9606 return 0; 9607 } 9608 9609 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 9610 struct bpf_prog *old_prog) 9611 { 9612 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9613 enum bpf_xdp_mode mode; 9614 bpf_op_t bpf_op; 9615 int err = 0; 9616 9617 rtnl_lock(); 9618 9619 /* link might have been auto-released already, so fail */ 9620 if (!xdp_link->dev) { 9621 err = -ENOLINK; 9622 goto out_unlock; 9623 } 9624 9625 if (old_prog && link->prog != old_prog) { 9626 err = -EPERM; 9627 goto out_unlock; 9628 } 9629 old_prog = link->prog; 9630 if (old_prog->type != new_prog->type || 9631 old_prog->expected_attach_type != new_prog->expected_attach_type) { 9632 err = -EINVAL; 9633 goto out_unlock; 9634 } 9635 9636 if (old_prog == new_prog) { 9637 /* no-op, don't disturb drivers */ 9638 bpf_prog_put(new_prog); 9639 goto out_unlock; 9640 } 9641 9642 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 9643 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9644 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9645 xdp_link->flags, new_prog); 9646 if (err) 9647 goto out_unlock; 9648 9649 old_prog = xchg(&link->prog, new_prog); 9650 bpf_prog_put(old_prog); 9651 9652 out_unlock: 9653 rtnl_unlock(); 9654 return err; 9655 } 9656 9657 static const struct bpf_link_ops bpf_xdp_link_lops = { 9658 .release = bpf_xdp_link_release, 9659 .dealloc = bpf_xdp_link_dealloc, 9660 .detach = bpf_xdp_link_detach, 9661 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9662 .fill_link_info = bpf_xdp_link_fill_link_info, 9663 .update_prog = bpf_xdp_link_update, 9664 }; 9665 9666 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9667 { 9668 struct net *net = current->nsproxy->net_ns; 9669 struct bpf_link_primer link_primer; 9670 struct netlink_ext_ack extack = {}; 9671 struct bpf_xdp_link *link; 9672 struct net_device *dev; 9673 int err, fd; 9674 9675 rtnl_lock(); 9676 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9677 if (!dev) { 9678 rtnl_unlock(); 9679 return -EINVAL; 9680 } 9681 9682 link = kzalloc(sizeof(*link), GFP_USER); 9683 if (!link) { 9684 err = -ENOMEM; 9685 goto unlock; 9686 } 9687 9688 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9689 link->dev = dev; 9690 link->flags = attr->link_create.flags; 9691 9692 err = bpf_link_prime(&link->link, &link_primer); 9693 if (err) { 9694 kfree(link); 9695 goto unlock; 9696 } 9697 9698 err = dev_xdp_attach_link(dev, &extack, link); 9699 rtnl_unlock(); 9700 9701 if (err) { 9702 link->dev = NULL; 9703 bpf_link_cleanup(&link_primer); 9704 trace_bpf_xdp_link_attach_failed(extack._msg); 9705 goto out_put_dev; 9706 } 9707 9708 fd = bpf_link_settle(&link_primer); 9709 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9710 dev_put(dev); 9711 return fd; 9712 9713 unlock: 9714 rtnl_unlock(); 9715 9716 out_put_dev: 9717 dev_put(dev); 9718 return err; 9719 } 9720 9721 /** 9722 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9723 * @dev: device 9724 * @extack: netlink extended ack 9725 * @fd: new program fd or negative value to clear 9726 * @expected_fd: old program fd that userspace expects to replace or clear 9727 * @flags: xdp-related flags 9728 * 9729 * Set or clear a bpf program for a device 9730 */ 9731 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9732 int fd, int expected_fd, u32 flags) 9733 { 9734 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9735 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9736 int err; 9737 9738 ASSERT_RTNL(); 9739 9740 if (fd >= 0) { 9741 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9742 mode != XDP_MODE_SKB); 9743 if (IS_ERR(new_prog)) 9744 return PTR_ERR(new_prog); 9745 } 9746 9747 if (expected_fd >= 0) { 9748 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9749 mode != XDP_MODE_SKB); 9750 if (IS_ERR(old_prog)) { 9751 err = PTR_ERR(old_prog); 9752 old_prog = NULL; 9753 goto err_out; 9754 } 9755 } 9756 9757 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9758 9759 err_out: 9760 if (err && new_prog) 9761 bpf_prog_put(new_prog); 9762 if (old_prog) 9763 bpf_prog_put(old_prog); 9764 return err; 9765 } 9766 9767 /** 9768 * dev_index_reserve() - allocate an ifindex in a namespace 9769 * @net: the applicable net namespace 9770 * @ifindex: requested ifindex, pass %0 to get one allocated 9771 * 9772 * Allocate a ifindex for a new device. Caller must either use the ifindex 9773 * to store the device (via list_netdevice()) or call dev_index_release() 9774 * to give the index up. 9775 * 9776 * Return: a suitable unique value for a new device interface number or -errno. 9777 */ 9778 static int dev_index_reserve(struct net *net, u32 ifindex) 9779 { 9780 int err; 9781 9782 if (ifindex > INT_MAX) { 9783 DEBUG_NET_WARN_ON_ONCE(1); 9784 return -EINVAL; 9785 } 9786 9787 if (!ifindex) 9788 err = xa_alloc_cyclic(&net->dev_by_index, &ifindex, NULL, 9789 xa_limit_31b, &net->ifindex, GFP_KERNEL); 9790 else 9791 err = xa_insert(&net->dev_by_index, ifindex, NULL, GFP_KERNEL); 9792 if (err < 0) 9793 return err; 9794 9795 return ifindex; 9796 } 9797 9798 static void dev_index_release(struct net *net, int ifindex) 9799 { 9800 /* Expect only unused indexes, unlist_netdevice() removes the used */ 9801 WARN_ON(xa_erase(&net->dev_by_index, ifindex)); 9802 } 9803 9804 /* Delayed registration/unregisteration */ 9805 LIST_HEAD(net_todo_list); 9806 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9807 atomic_t dev_unreg_count = ATOMIC_INIT(0); 9808 9809 static void net_set_todo(struct net_device *dev) 9810 { 9811 list_add_tail(&dev->todo_list, &net_todo_list); 9812 } 9813 9814 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9815 struct net_device *upper, netdev_features_t features) 9816 { 9817 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9818 netdev_features_t feature; 9819 int feature_bit; 9820 9821 for_each_netdev_feature(upper_disables, feature_bit) { 9822 feature = __NETIF_F_BIT(feature_bit); 9823 if (!(upper->wanted_features & feature) 9824 && (features & feature)) { 9825 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9826 &feature, upper->name); 9827 features &= ~feature; 9828 } 9829 } 9830 9831 return features; 9832 } 9833 9834 static void netdev_sync_lower_features(struct net_device *upper, 9835 struct net_device *lower, netdev_features_t features) 9836 { 9837 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9838 netdev_features_t feature; 9839 int feature_bit; 9840 9841 for_each_netdev_feature(upper_disables, feature_bit) { 9842 feature = __NETIF_F_BIT(feature_bit); 9843 if (!(features & feature) && (lower->features & feature)) { 9844 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9845 &feature, lower->name); 9846 lower->wanted_features &= ~feature; 9847 __netdev_update_features(lower); 9848 9849 if (unlikely(lower->features & feature)) 9850 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9851 &feature, lower->name); 9852 else 9853 netdev_features_change(lower); 9854 } 9855 } 9856 } 9857 9858 static netdev_features_t netdev_fix_features(struct net_device *dev, 9859 netdev_features_t features) 9860 { 9861 /* Fix illegal checksum combinations */ 9862 if ((features & NETIF_F_HW_CSUM) && 9863 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9864 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9865 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9866 } 9867 9868 /* TSO requires that SG is present as well. */ 9869 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9870 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9871 features &= ~NETIF_F_ALL_TSO; 9872 } 9873 9874 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9875 !(features & NETIF_F_IP_CSUM)) { 9876 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9877 features &= ~NETIF_F_TSO; 9878 features &= ~NETIF_F_TSO_ECN; 9879 } 9880 9881 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9882 !(features & NETIF_F_IPV6_CSUM)) { 9883 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9884 features &= ~NETIF_F_TSO6; 9885 } 9886 9887 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9888 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9889 features &= ~NETIF_F_TSO_MANGLEID; 9890 9891 /* TSO ECN requires that TSO is present as well. */ 9892 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9893 features &= ~NETIF_F_TSO_ECN; 9894 9895 /* Software GSO depends on SG. */ 9896 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9897 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9898 features &= ~NETIF_F_GSO; 9899 } 9900 9901 /* GSO partial features require GSO partial be set */ 9902 if ((features & dev->gso_partial_features) && 9903 !(features & NETIF_F_GSO_PARTIAL)) { 9904 netdev_dbg(dev, 9905 "Dropping partially supported GSO features since no GSO partial.\n"); 9906 features &= ~dev->gso_partial_features; 9907 } 9908 9909 if (!(features & NETIF_F_RXCSUM)) { 9910 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9911 * successfully merged by hardware must also have the 9912 * checksum verified by hardware. If the user does not 9913 * want to enable RXCSUM, logically, we should disable GRO_HW. 9914 */ 9915 if (features & NETIF_F_GRO_HW) { 9916 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9917 features &= ~NETIF_F_GRO_HW; 9918 } 9919 } 9920 9921 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9922 if (features & NETIF_F_RXFCS) { 9923 if (features & NETIF_F_LRO) { 9924 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9925 features &= ~NETIF_F_LRO; 9926 } 9927 9928 if (features & NETIF_F_GRO_HW) { 9929 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9930 features &= ~NETIF_F_GRO_HW; 9931 } 9932 } 9933 9934 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9935 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9936 features &= ~NETIF_F_LRO; 9937 } 9938 9939 if (features & NETIF_F_HW_TLS_TX) { 9940 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9941 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9942 bool hw_csum = features & NETIF_F_HW_CSUM; 9943 9944 if (!ip_csum && !hw_csum) { 9945 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9946 features &= ~NETIF_F_HW_TLS_TX; 9947 } 9948 } 9949 9950 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9951 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9952 features &= ~NETIF_F_HW_TLS_RX; 9953 } 9954 9955 return features; 9956 } 9957 9958 int __netdev_update_features(struct net_device *dev) 9959 { 9960 struct net_device *upper, *lower; 9961 netdev_features_t features; 9962 struct list_head *iter; 9963 int err = -1; 9964 9965 ASSERT_RTNL(); 9966 9967 features = netdev_get_wanted_features(dev); 9968 9969 if (dev->netdev_ops->ndo_fix_features) 9970 features = dev->netdev_ops->ndo_fix_features(dev, features); 9971 9972 /* driver might be less strict about feature dependencies */ 9973 features = netdev_fix_features(dev, features); 9974 9975 /* some features can't be enabled if they're off on an upper device */ 9976 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9977 features = netdev_sync_upper_features(dev, upper, features); 9978 9979 if (dev->features == features) 9980 goto sync_lower; 9981 9982 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9983 &dev->features, &features); 9984 9985 if (dev->netdev_ops->ndo_set_features) 9986 err = dev->netdev_ops->ndo_set_features(dev, features); 9987 else 9988 err = 0; 9989 9990 if (unlikely(err < 0)) { 9991 netdev_err(dev, 9992 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9993 err, &features, &dev->features); 9994 /* return non-0 since some features might have changed and 9995 * it's better to fire a spurious notification than miss it 9996 */ 9997 return -1; 9998 } 9999 10000 sync_lower: 10001 /* some features must be disabled on lower devices when disabled 10002 * on an upper device (think: bonding master or bridge) 10003 */ 10004 netdev_for_each_lower_dev(dev, lower, iter) 10005 netdev_sync_lower_features(dev, lower, features); 10006 10007 if (!err) { 10008 netdev_features_t diff = features ^ dev->features; 10009 10010 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 10011 /* udp_tunnel_{get,drop}_rx_info both need 10012 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 10013 * device, or they won't do anything. 10014 * Thus we need to update dev->features 10015 * *before* calling udp_tunnel_get_rx_info, 10016 * but *after* calling udp_tunnel_drop_rx_info. 10017 */ 10018 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 10019 dev->features = features; 10020 udp_tunnel_get_rx_info(dev); 10021 } else { 10022 udp_tunnel_drop_rx_info(dev); 10023 } 10024 } 10025 10026 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 10027 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 10028 dev->features = features; 10029 err |= vlan_get_rx_ctag_filter_info(dev); 10030 } else { 10031 vlan_drop_rx_ctag_filter_info(dev); 10032 } 10033 } 10034 10035 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 10036 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 10037 dev->features = features; 10038 err |= vlan_get_rx_stag_filter_info(dev); 10039 } else { 10040 vlan_drop_rx_stag_filter_info(dev); 10041 } 10042 } 10043 10044 dev->features = features; 10045 } 10046 10047 return err < 0 ? 0 : 1; 10048 } 10049 10050 /** 10051 * netdev_update_features - recalculate device features 10052 * @dev: the device to check 10053 * 10054 * Recalculate dev->features set and send notifications if it 10055 * has changed. Should be called after driver or hardware dependent 10056 * conditions might have changed that influence the features. 10057 */ 10058 void netdev_update_features(struct net_device *dev) 10059 { 10060 if (__netdev_update_features(dev)) 10061 netdev_features_change(dev); 10062 } 10063 EXPORT_SYMBOL(netdev_update_features); 10064 10065 /** 10066 * netdev_change_features - recalculate device features 10067 * @dev: the device to check 10068 * 10069 * Recalculate dev->features set and send notifications even 10070 * if they have not changed. Should be called instead of 10071 * netdev_update_features() if also dev->vlan_features might 10072 * have changed to allow the changes to be propagated to stacked 10073 * VLAN devices. 10074 */ 10075 void netdev_change_features(struct net_device *dev) 10076 { 10077 __netdev_update_features(dev); 10078 netdev_features_change(dev); 10079 } 10080 EXPORT_SYMBOL(netdev_change_features); 10081 10082 /** 10083 * netif_stacked_transfer_operstate - transfer operstate 10084 * @rootdev: the root or lower level device to transfer state from 10085 * @dev: the device to transfer operstate to 10086 * 10087 * Transfer operational state from root to device. This is normally 10088 * called when a stacking relationship exists between the root 10089 * device and the device(a leaf device). 10090 */ 10091 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 10092 struct net_device *dev) 10093 { 10094 if (rootdev->operstate == IF_OPER_DORMANT) 10095 netif_dormant_on(dev); 10096 else 10097 netif_dormant_off(dev); 10098 10099 if (rootdev->operstate == IF_OPER_TESTING) 10100 netif_testing_on(dev); 10101 else 10102 netif_testing_off(dev); 10103 10104 if (netif_carrier_ok(rootdev)) 10105 netif_carrier_on(dev); 10106 else 10107 netif_carrier_off(dev); 10108 } 10109 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 10110 10111 static int netif_alloc_rx_queues(struct net_device *dev) 10112 { 10113 unsigned int i, count = dev->num_rx_queues; 10114 struct netdev_rx_queue *rx; 10115 size_t sz = count * sizeof(*rx); 10116 int err = 0; 10117 10118 BUG_ON(count < 1); 10119 10120 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10121 if (!rx) 10122 return -ENOMEM; 10123 10124 dev->_rx = rx; 10125 10126 for (i = 0; i < count; i++) { 10127 rx[i].dev = dev; 10128 10129 /* XDP RX-queue setup */ 10130 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 10131 if (err < 0) 10132 goto err_rxq_info; 10133 } 10134 return 0; 10135 10136 err_rxq_info: 10137 /* Rollback successful reg's and free other resources */ 10138 while (i--) 10139 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 10140 kvfree(dev->_rx); 10141 dev->_rx = NULL; 10142 return err; 10143 } 10144 10145 static void netif_free_rx_queues(struct net_device *dev) 10146 { 10147 unsigned int i, count = dev->num_rx_queues; 10148 10149 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 10150 if (!dev->_rx) 10151 return; 10152 10153 for (i = 0; i < count; i++) 10154 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 10155 10156 kvfree(dev->_rx); 10157 } 10158 10159 static void netdev_init_one_queue(struct net_device *dev, 10160 struct netdev_queue *queue, void *_unused) 10161 { 10162 /* Initialize queue lock */ 10163 spin_lock_init(&queue->_xmit_lock); 10164 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 10165 queue->xmit_lock_owner = -1; 10166 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 10167 queue->dev = dev; 10168 #ifdef CONFIG_BQL 10169 dql_init(&queue->dql, HZ); 10170 #endif 10171 } 10172 10173 static void netif_free_tx_queues(struct net_device *dev) 10174 { 10175 kvfree(dev->_tx); 10176 } 10177 10178 static int netif_alloc_netdev_queues(struct net_device *dev) 10179 { 10180 unsigned int count = dev->num_tx_queues; 10181 struct netdev_queue *tx; 10182 size_t sz = count * sizeof(*tx); 10183 10184 if (count < 1 || count > 0xffff) 10185 return -EINVAL; 10186 10187 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10188 if (!tx) 10189 return -ENOMEM; 10190 10191 dev->_tx = tx; 10192 10193 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 10194 spin_lock_init(&dev->tx_global_lock); 10195 10196 return 0; 10197 } 10198 10199 void netif_tx_stop_all_queues(struct net_device *dev) 10200 { 10201 unsigned int i; 10202 10203 for (i = 0; i < dev->num_tx_queues; i++) { 10204 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 10205 10206 netif_tx_stop_queue(txq); 10207 } 10208 } 10209 EXPORT_SYMBOL(netif_tx_stop_all_queues); 10210 10211 static int netdev_do_alloc_pcpu_stats(struct net_device *dev) 10212 { 10213 void __percpu *v; 10214 10215 /* Drivers implementing ndo_get_peer_dev must support tstat 10216 * accounting, so that skb_do_redirect() can bump the dev's 10217 * RX stats upon network namespace switch. 10218 */ 10219 if (dev->netdev_ops->ndo_get_peer_dev && 10220 dev->pcpu_stat_type != NETDEV_PCPU_STAT_TSTATS) 10221 return -EOPNOTSUPP; 10222 10223 switch (dev->pcpu_stat_type) { 10224 case NETDEV_PCPU_STAT_NONE: 10225 return 0; 10226 case NETDEV_PCPU_STAT_LSTATS: 10227 v = dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); 10228 break; 10229 case NETDEV_PCPU_STAT_TSTATS: 10230 v = dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 10231 break; 10232 case NETDEV_PCPU_STAT_DSTATS: 10233 v = dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats); 10234 break; 10235 default: 10236 return -EINVAL; 10237 } 10238 10239 return v ? 0 : -ENOMEM; 10240 } 10241 10242 static void netdev_do_free_pcpu_stats(struct net_device *dev) 10243 { 10244 switch (dev->pcpu_stat_type) { 10245 case NETDEV_PCPU_STAT_NONE: 10246 return; 10247 case NETDEV_PCPU_STAT_LSTATS: 10248 free_percpu(dev->lstats); 10249 break; 10250 case NETDEV_PCPU_STAT_TSTATS: 10251 free_percpu(dev->tstats); 10252 break; 10253 case NETDEV_PCPU_STAT_DSTATS: 10254 free_percpu(dev->dstats); 10255 break; 10256 } 10257 } 10258 10259 /** 10260 * register_netdevice() - register a network device 10261 * @dev: device to register 10262 * 10263 * Take a prepared network device structure and make it externally accessible. 10264 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 10265 * Callers must hold the rtnl lock - you may want register_netdev() 10266 * instead of this. 10267 */ 10268 int register_netdevice(struct net_device *dev) 10269 { 10270 int ret; 10271 struct net *net = dev_net(dev); 10272 10273 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 10274 NETDEV_FEATURE_COUNT); 10275 BUG_ON(dev_boot_phase); 10276 ASSERT_RTNL(); 10277 10278 might_sleep(); 10279 10280 /* When net_device's are persistent, this will be fatal. */ 10281 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 10282 BUG_ON(!net); 10283 10284 ret = ethtool_check_ops(dev->ethtool_ops); 10285 if (ret) 10286 return ret; 10287 10288 spin_lock_init(&dev->addr_list_lock); 10289 netdev_set_addr_lockdep_class(dev); 10290 10291 ret = dev_get_valid_name(net, dev, dev->name); 10292 if (ret < 0) 10293 goto out; 10294 10295 ret = -ENOMEM; 10296 dev->name_node = netdev_name_node_head_alloc(dev); 10297 if (!dev->name_node) 10298 goto out; 10299 10300 /* Init, if this function is available */ 10301 if (dev->netdev_ops->ndo_init) { 10302 ret = dev->netdev_ops->ndo_init(dev); 10303 if (ret) { 10304 if (ret > 0) 10305 ret = -EIO; 10306 goto err_free_name; 10307 } 10308 } 10309 10310 if (((dev->hw_features | dev->features) & 10311 NETIF_F_HW_VLAN_CTAG_FILTER) && 10312 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 10313 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 10314 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 10315 ret = -EINVAL; 10316 goto err_uninit; 10317 } 10318 10319 ret = netdev_do_alloc_pcpu_stats(dev); 10320 if (ret) 10321 goto err_uninit; 10322 10323 ret = dev_index_reserve(net, dev->ifindex); 10324 if (ret < 0) 10325 goto err_free_pcpu; 10326 dev->ifindex = ret; 10327 10328 /* Transfer changeable features to wanted_features and enable 10329 * software offloads (GSO and GRO). 10330 */ 10331 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 10332 dev->features |= NETIF_F_SOFT_FEATURES; 10333 10334 if (dev->udp_tunnel_nic_info) { 10335 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10336 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10337 } 10338 10339 dev->wanted_features = dev->features & dev->hw_features; 10340 10341 if (!(dev->flags & IFF_LOOPBACK)) 10342 dev->hw_features |= NETIF_F_NOCACHE_COPY; 10343 10344 /* If IPv4 TCP segmentation offload is supported we should also 10345 * allow the device to enable segmenting the frame with the option 10346 * of ignoring a static IP ID value. This doesn't enable the 10347 * feature itself but allows the user to enable it later. 10348 */ 10349 if (dev->hw_features & NETIF_F_TSO) 10350 dev->hw_features |= NETIF_F_TSO_MANGLEID; 10351 if (dev->vlan_features & NETIF_F_TSO) 10352 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10353 if (dev->mpls_features & NETIF_F_TSO) 10354 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10355 if (dev->hw_enc_features & NETIF_F_TSO) 10356 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10357 10358 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10359 */ 10360 dev->vlan_features |= NETIF_F_HIGHDMA; 10361 10362 /* Make NETIF_F_SG inheritable to tunnel devices. 10363 */ 10364 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10365 10366 /* Make NETIF_F_SG inheritable to MPLS. 10367 */ 10368 dev->mpls_features |= NETIF_F_SG; 10369 10370 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10371 ret = notifier_to_errno(ret); 10372 if (ret) 10373 goto err_ifindex_release; 10374 10375 ret = netdev_register_kobject(dev); 10376 10377 WRITE_ONCE(dev->reg_state, ret ? NETREG_UNREGISTERED : NETREG_REGISTERED); 10378 10379 if (ret) 10380 goto err_uninit_notify; 10381 10382 __netdev_update_features(dev); 10383 10384 /* 10385 * Default initial state at registry is that the 10386 * device is present. 10387 */ 10388 10389 set_bit(__LINK_STATE_PRESENT, &dev->state); 10390 10391 linkwatch_init_dev(dev); 10392 10393 dev_init_scheduler(dev); 10394 10395 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10396 list_netdevice(dev); 10397 10398 add_device_randomness(dev->dev_addr, dev->addr_len); 10399 10400 /* If the device has permanent device address, driver should 10401 * set dev_addr and also addr_assign_type should be set to 10402 * NET_ADDR_PERM (default value). 10403 */ 10404 if (dev->addr_assign_type == NET_ADDR_PERM) 10405 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10406 10407 /* Notify protocols, that a new device appeared. */ 10408 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10409 ret = notifier_to_errno(ret); 10410 if (ret) { 10411 /* Expect explicit free_netdev() on failure */ 10412 dev->needs_free_netdev = false; 10413 unregister_netdevice_queue(dev, NULL); 10414 goto out; 10415 } 10416 /* 10417 * Prevent userspace races by waiting until the network 10418 * device is fully setup before sending notifications. 10419 */ 10420 if (!dev->rtnl_link_ops || 10421 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10422 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 10423 10424 out: 10425 return ret; 10426 10427 err_uninit_notify: 10428 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10429 err_ifindex_release: 10430 dev_index_release(net, dev->ifindex); 10431 err_free_pcpu: 10432 netdev_do_free_pcpu_stats(dev); 10433 err_uninit: 10434 if (dev->netdev_ops->ndo_uninit) 10435 dev->netdev_ops->ndo_uninit(dev); 10436 if (dev->priv_destructor) 10437 dev->priv_destructor(dev); 10438 err_free_name: 10439 netdev_name_node_free(dev->name_node); 10440 goto out; 10441 } 10442 EXPORT_SYMBOL(register_netdevice); 10443 10444 /* Initialize the core of a dummy net device. 10445 * This is useful if you are calling this function after alloc_netdev(), 10446 * since it does not memset the net_device fields. 10447 */ 10448 static void init_dummy_netdev_core(struct net_device *dev) 10449 { 10450 /* make sure we BUG if trying to hit standard 10451 * register/unregister code path 10452 */ 10453 dev->reg_state = NETREG_DUMMY; 10454 10455 /* NAPI wants this */ 10456 INIT_LIST_HEAD(&dev->napi_list); 10457 10458 /* a dummy interface is started by default */ 10459 set_bit(__LINK_STATE_PRESENT, &dev->state); 10460 set_bit(__LINK_STATE_START, &dev->state); 10461 10462 /* napi_busy_loop stats accounting wants this */ 10463 dev_net_set(dev, &init_net); 10464 10465 /* Note : We dont allocate pcpu_refcnt for dummy devices, 10466 * because users of this 'device' dont need to change 10467 * its refcount. 10468 */ 10469 } 10470 10471 /** 10472 * init_dummy_netdev - init a dummy network device for NAPI 10473 * @dev: device to init 10474 * 10475 * This takes a network device structure and initializes the minimum 10476 * amount of fields so it can be used to schedule NAPI polls without 10477 * registering a full blown interface. This is to be used by drivers 10478 * that need to tie several hardware interfaces to a single NAPI 10479 * poll scheduler due to HW limitations. 10480 */ 10481 void init_dummy_netdev(struct net_device *dev) 10482 { 10483 /* Clear everything. Note we don't initialize spinlocks 10484 * as they aren't supposed to be taken by any of the 10485 * NAPI code and this dummy netdev is supposed to be 10486 * only ever used for NAPI polls 10487 */ 10488 memset(dev, 0, sizeof(struct net_device)); 10489 init_dummy_netdev_core(dev); 10490 } 10491 EXPORT_SYMBOL_GPL(init_dummy_netdev); 10492 10493 /** 10494 * register_netdev - register a network device 10495 * @dev: device to register 10496 * 10497 * Take a completed network device structure and add it to the kernel 10498 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 10499 * chain. 0 is returned on success. A negative errno code is returned 10500 * on a failure to set up the device, or if the name is a duplicate. 10501 * 10502 * This is a wrapper around register_netdevice that takes the rtnl semaphore 10503 * and expands the device name if you passed a format string to 10504 * alloc_netdev. 10505 */ 10506 int register_netdev(struct net_device *dev) 10507 { 10508 int err; 10509 10510 if (rtnl_lock_killable()) 10511 return -EINTR; 10512 err = register_netdevice(dev); 10513 rtnl_unlock(); 10514 return err; 10515 } 10516 EXPORT_SYMBOL(register_netdev); 10517 10518 int netdev_refcnt_read(const struct net_device *dev) 10519 { 10520 #ifdef CONFIG_PCPU_DEV_REFCNT 10521 int i, refcnt = 0; 10522 10523 for_each_possible_cpu(i) 10524 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 10525 return refcnt; 10526 #else 10527 return refcount_read(&dev->dev_refcnt); 10528 #endif 10529 } 10530 EXPORT_SYMBOL(netdev_refcnt_read); 10531 10532 int netdev_unregister_timeout_secs __read_mostly = 10; 10533 10534 #define WAIT_REFS_MIN_MSECS 1 10535 #define WAIT_REFS_MAX_MSECS 250 10536 /** 10537 * netdev_wait_allrefs_any - wait until all references are gone. 10538 * @list: list of net_devices to wait on 10539 * 10540 * This is called when unregistering network devices. 10541 * 10542 * Any protocol or device that holds a reference should register 10543 * for netdevice notification, and cleanup and put back the 10544 * reference if they receive an UNREGISTER event. 10545 * We can get stuck here if buggy protocols don't correctly 10546 * call dev_put. 10547 */ 10548 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 10549 { 10550 unsigned long rebroadcast_time, warning_time; 10551 struct net_device *dev; 10552 int wait = 0; 10553 10554 rebroadcast_time = warning_time = jiffies; 10555 10556 list_for_each_entry(dev, list, todo_list) 10557 if (netdev_refcnt_read(dev) == 1) 10558 return dev; 10559 10560 while (true) { 10561 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 10562 rtnl_lock(); 10563 10564 /* Rebroadcast unregister notification */ 10565 list_for_each_entry(dev, list, todo_list) 10566 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10567 10568 __rtnl_unlock(); 10569 rcu_barrier(); 10570 rtnl_lock(); 10571 10572 list_for_each_entry(dev, list, todo_list) 10573 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 10574 &dev->state)) { 10575 /* We must not have linkwatch events 10576 * pending on unregister. If this 10577 * happens, we simply run the queue 10578 * unscheduled, resulting in a noop 10579 * for this device. 10580 */ 10581 linkwatch_run_queue(); 10582 break; 10583 } 10584 10585 __rtnl_unlock(); 10586 10587 rebroadcast_time = jiffies; 10588 } 10589 10590 rcu_barrier(); 10591 10592 if (!wait) { 10593 wait = WAIT_REFS_MIN_MSECS; 10594 } else { 10595 msleep(wait); 10596 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 10597 } 10598 10599 list_for_each_entry(dev, list, todo_list) 10600 if (netdev_refcnt_read(dev) == 1) 10601 return dev; 10602 10603 if (time_after(jiffies, warning_time + 10604 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 10605 list_for_each_entry(dev, list, todo_list) { 10606 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 10607 dev->name, netdev_refcnt_read(dev)); 10608 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 10609 } 10610 10611 warning_time = jiffies; 10612 } 10613 } 10614 } 10615 10616 /* The sequence is: 10617 * 10618 * rtnl_lock(); 10619 * ... 10620 * register_netdevice(x1); 10621 * register_netdevice(x2); 10622 * ... 10623 * unregister_netdevice(y1); 10624 * unregister_netdevice(y2); 10625 * ... 10626 * rtnl_unlock(); 10627 * free_netdev(y1); 10628 * free_netdev(y2); 10629 * 10630 * We are invoked by rtnl_unlock(). 10631 * This allows us to deal with problems: 10632 * 1) We can delete sysfs objects which invoke hotplug 10633 * without deadlocking with linkwatch via keventd. 10634 * 2) Since we run with the RTNL semaphore not held, we can sleep 10635 * safely in order to wait for the netdev refcnt to drop to zero. 10636 * 10637 * We must not return until all unregister events added during 10638 * the interval the lock was held have been completed. 10639 */ 10640 void netdev_run_todo(void) 10641 { 10642 struct net_device *dev, *tmp; 10643 struct list_head list; 10644 int cnt; 10645 #ifdef CONFIG_LOCKDEP 10646 struct list_head unlink_list; 10647 10648 list_replace_init(&net_unlink_list, &unlink_list); 10649 10650 while (!list_empty(&unlink_list)) { 10651 struct net_device *dev = list_first_entry(&unlink_list, 10652 struct net_device, 10653 unlink_list); 10654 list_del_init(&dev->unlink_list); 10655 dev->nested_level = dev->lower_level - 1; 10656 } 10657 #endif 10658 10659 /* Snapshot list, allow later requests */ 10660 list_replace_init(&net_todo_list, &list); 10661 10662 __rtnl_unlock(); 10663 10664 /* Wait for rcu callbacks to finish before next phase */ 10665 if (!list_empty(&list)) 10666 rcu_barrier(); 10667 10668 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 10669 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 10670 netdev_WARN(dev, "run_todo but not unregistering\n"); 10671 list_del(&dev->todo_list); 10672 continue; 10673 } 10674 10675 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERED); 10676 linkwatch_sync_dev(dev); 10677 } 10678 10679 cnt = 0; 10680 while (!list_empty(&list)) { 10681 dev = netdev_wait_allrefs_any(&list); 10682 list_del(&dev->todo_list); 10683 10684 /* paranoia */ 10685 BUG_ON(netdev_refcnt_read(dev) != 1); 10686 BUG_ON(!list_empty(&dev->ptype_all)); 10687 BUG_ON(!list_empty(&dev->ptype_specific)); 10688 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 10689 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 10690 10691 netdev_do_free_pcpu_stats(dev); 10692 if (dev->priv_destructor) 10693 dev->priv_destructor(dev); 10694 if (dev->needs_free_netdev) 10695 free_netdev(dev); 10696 10697 cnt++; 10698 10699 /* Free network device */ 10700 kobject_put(&dev->dev.kobj); 10701 } 10702 if (cnt && atomic_sub_and_test(cnt, &dev_unreg_count)) 10703 wake_up(&netdev_unregistering_wq); 10704 } 10705 10706 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 10707 * all the same fields in the same order as net_device_stats, with only 10708 * the type differing, but rtnl_link_stats64 may have additional fields 10709 * at the end for newer counters. 10710 */ 10711 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 10712 const struct net_device_stats *netdev_stats) 10713 { 10714 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t); 10715 const atomic_long_t *src = (atomic_long_t *)netdev_stats; 10716 u64 *dst = (u64 *)stats64; 10717 10718 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 10719 for (i = 0; i < n; i++) 10720 dst[i] = (unsigned long)atomic_long_read(&src[i]); 10721 /* zero out counters that only exist in rtnl_link_stats64 */ 10722 memset((char *)stats64 + n * sizeof(u64), 0, 10723 sizeof(*stats64) - n * sizeof(u64)); 10724 } 10725 EXPORT_SYMBOL(netdev_stats_to_stats64); 10726 10727 static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc( 10728 struct net_device *dev) 10729 { 10730 struct net_device_core_stats __percpu *p; 10731 10732 p = alloc_percpu_gfp(struct net_device_core_stats, 10733 GFP_ATOMIC | __GFP_NOWARN); 10734 10735 if (p && cmpxchg(&dev->core_stats, NULL, p)) 10736 free_percpu(p); 10737 10738 /* This READ_ONCE() pairs with the cmpxchg() above */ 10739 return READ_ONCE(dev->core_stats); 10740 } 10741 10742 noinline void netdev_core_stats_inc(struct net_device *dev, u32 offset) 10743 { 10744 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10745 struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); 10746 unsigned long __percpu *field; 10747 10748 if (unlikely(!p)) { 10749 p = netdev_core_stats_alloc(dev); 10750 if (!p) 10751 return; 10752 } 10753 10754 field = (__force unsigned long __percpu *)((__force void *)p + offset); 10755 this_cpu_inc(*field); 10756 } 10757 EXPORT_SYMBOL_GPL(netdev_core_stats_inc); 10758 10759 /** 10760 * dev_get_stats - get network device statistics 10761 * @dev: device to get statistics from 10762 * @storage: place to store stats 10763 * 10764 * Get network statistics from device. Return @storage. 10765 * The device driver may provide its own method by setting 10766 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10767 * otherwise the internal statistics structure is used. 10768 */ 10769 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10770 struct rtnl_link_stats64 *storage) 10771 { 10772 const struct net_device_ops *ops = dev->netdev_ops; 10773 const struct net_device_core_stats __percpu *p; 10774 10775 if (ops->ndo_get_stats64) { 10776 memset(storage, 0, sizeof(*storage)); 10777 ops->ndo_get_stats64(dev, storage); 10778 } else if (ops->ndo_get_stats) { 10779 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10780 } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) { 10781 dev_get_tstats64(dev, storage); 10782 } else { 10783 netdev_stats_to_stats64(storage, &dev->stats); 10784 } 10785 10786 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10787 p = READ_ONCE(dev->core_stats); 10788 if (p) { 10789 const struct net_device_core_stats *core_stats; 10790 int i; 10791 10792 for_each_possible_cpu(i) { 10793 core_stats = per_cpu_ptr(p, i); 10794 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 10795 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 10796 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 10797 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 10798 } 10799 } 10800 return storage; 10801 } 10802 EXPORT_SYMBOL(dev_get_stats); 10803 10804 /** 10805 * dev_fetch_sw_netstats - get per-cpu network device statistics 10806 * @s: place to store stats 10807 * @netstats: per-cpu network stats to read from 10808 * 10809 * Read per-cpu network statistics and populate the related fields in @s. 10810 */ 10811 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10812 const struct pcpu_sw_netstats __percpu *netstats) 10813 { 10814 int cpu; 10815 10816 for_each_possible_cpu(cpu) { 10817 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 10818 const struct pcpu_sw_netstats *stats; 10819 unsigned int start; 10820 10821 stats = per_cpu_ptr(netstats, cpu); 10822 do { 10823 start = u64_stats_fetch_begin(&stats->syncp); 10824 rx_packets = u64_stats_read(&stats->rx_packets); 10825 rx_bytes = u64_stats_read(&stats->rx_bytes); 10826 tx_packets = u64_stats_read(&stats->tx_packets); 10827 tx_bytes = u64_stats_read(&stats->tx_bytes); 10828 } while (u64_stats_fetch_retry(&stats->syncp, start)); 10829 10830 s->rx_packets += rx_packets; 10831 s->rx_bytes += rx_bytes; 10832 s->tx_packets += tx_packets; 10833 s->tx_bytes += tx_bytes; 10834 } 10835 } 10836 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10837 10838 /** 10839 * dev_get_tstats64 - ndo_get_stats64 implementation 10840 * @dev: device to get statistics from 10841 * @s: place to store stats 10842 * 10843 * Populate @s from dev->stats and dev->tstats. Can be used as 10844 * ndo_get_stats64() callback. 10845 */ 10846 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10847 { 10848 netdev_stats_to_stats64(s, &dev->stats); 10849 dev_fetch_sw_netstats(s, dev->tstats); 10850 } 10851 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10852 10853 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10854 { 10855 struct netdev_queue *queue = dev_ingress_queue(dev); 10856 10857 #ifdef CONFIG_NET_CLS_ACT 10858 if (queue) 10859 return queue; 10860 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10861 if (!queue) 10862 return NULL; 10863 netdev_init_one_queue(dev, queue, NULL); 10864 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10865 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc); 10866 rcu_assign_pointer(dev->ingress_queue, queue); 10867 #endif 10868 return queue; 10869 } 10870 10871 static const struct ethtool_ops default_ethtool_ops; 10872 10873 void netdev_set_default_ethtool_ops(struct net_device *dev, 10874 const struct ethtool_ops *ops) 10875 { 10876 if (dev->ethtool_ops == &default_ethtool_ops) 10877 dev->ethtool_ops = ops; 10878 } 10879 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10880 10881 /** 10882 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default 10883 * @dev: netdev to enable the IRQ coalescing on 10884 * 10885 * Sets a conservative default for SW IRQ coalescing. Users can use 10886 * sysfs attributes to override the default values. 10887 */ 10888 void netdev_sw_irq_coalesce_default_on(struct net_device *dev) 10889 { 10890 WARN_ON(dev->reg_state == NETREG_REGISTERED); 10891 10892 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { 10893 dev->gro_flush_timeout = 20000; 10894 dev->napi_defer_hard_irqs = 1; 10895 } 10896 } 10897 EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); 10898 10899 void netdev_freemem(struct net_device *dev) 10900 { 10901 char *addr = (char *)dev - dev->padded; 10902 10903 kvfree(addr); 10904 } 10905 10906 /** 10907 * alloc_netdev_mqs - allocate network device 10908 * @sizeof_priv: size of private data to allocate space for 10909 * @name: device name format string 10910 * @name_assign_type: origin of device name 10911 * @setup: callback to initialize device 10912 * @txqs: the number of TX subqueues to allocate 10913 * @rxqs: the number of RX subqueues to allocate 10914 * 10915 * Allocates a struct net_device with private data area for driver use 10916 * and performs basic initialization. Also allocates subqueue structs 10917 * for each queue on the device. 10918 */ 10919 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10920 unsigned char name_assign_type, 10921 void (*setup)(struct net_device *), 10922 unsigned int txqs, unsigned int rxqs) 10923 { 10924 struct net_device *dev; 10925 unsigned int alloc_size; 10926 struct net_device *p; 10927 10928 BUG_ON(strlen(name) >= sizeof(dev->name)); 10929 10930 if (txqs < 1) { 10931 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10932 return NULL; 10933 } 10934 10935 if (rxqs < 1) { 10936 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10937 return NULL; 10938 } 10939 10940 alloc_size = sizeof(struct net_device); 10941 if (sizeof_priv) { 10942 /* ensure 32-byte alignment of private area */ 10943 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10944 alloc_size += sizeof_priv; 10945 } 10946 /* ensure 32-byte alignment of whole construct */ 10947 alloc_size += NETDEV_ALIGN - 1; 10948 10949 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10950 if (!p) 10951 return NULL; 10952 10953 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10954 dev->padded = (char *)dev - (char *)p; 10955 10956 ref_tracker_dir_init(&dev->refcnt_tracker, 128, name); 10957 #ifdef CONFIG_PCPU_DEV_REFCNT 10958 dev->pcpu_refcnt = alloc_percpu(int); 10959 if (!dev->pcpu_refcnt) 10960 goto free_dev; 10961 __dev_hold(dev); 10962 #else 10963 refcount_set(&dev->dev_refcnt, 1); 10964 #endif 10965 10966 if (dev_addr_init(dev)) 10967 goto free_pcpu; 10968 10969 dev_mc_init(dev); 10970 dev_uc_init(dev); 10971 10972 dev_net_set(dev, &init_net); 10973 10974 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 10975 dev->xdp_zc_max_segs = 1; 10976 dev->gso_max_segs = GSO_MAX_SEGS; 10977 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 10978 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE; 10979 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE; 10980 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 10981 dev->tso_max_segs = TSO_MAX_SEGS; 10982 dev->upper_level = 1; 10983 dev->lower_level = 1; 10984 #ifdef CONFIG_LOCKDEP 10985 dev->nested_level = 0; 10986 INIT_LIST_HEAD(&dev->unlink_list); 10987 #endif 10988 10989 INIT_LIST_HEAD(&dev->napi_list); 10990 INIT_LIST_HEAD(&dev->unreg_list); 10991 INIT_LIST_HEAD(&dev->close_list); 10992 INIT_LIST_HEAD(&dev->link_watch_list); 10993 INIT_LIST_HEAD(&dev->adj_list.upper); 10994 INIT_LIST_HEAD(&dev->adj_list.lower); 10995 INIT_LIST_HEAD(&dev->ptype_all); 10996 INIT_LIST_HEAD(&dev->ptype_specific); 10997 INIT_LIST_HEAD(&dev->net_notifier_list); 10998 #ifdef CONFIG_NET_SCHED 10999 hash_init(dev->qdisc_hash); 11000 #endif 11001 dev->link_topo = phy_link_topo_create(dev); 11002 if (IS_ERR(dev->link_topo)) { 11003 dev->link_topo = NULL; 11004 goto free_all; 11005 } 11006 11007 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 11008 setup(dev); 11009 11010 if (!dev->tx_queue_len) { 11011 dev->priv_flags |= IFF_NO_QUEUE; 11012 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 11013 } 11014 11015 dev->num_tx_queues = txqs; 11016 dev->real_num_tx_queues = txqs; 11017 if (netif_alloc_netdev_queues(dev)) 11018 goto free_all; 11019 11020 dev->num_rx_queues = rxqs; 11021 dev->real_num_rx_queues = rxqs; 11022 if (netif_alloc_rx_queues(dev)) 11023 goto free_all; 11024 11025 strcpy(dev->name, name); 11026 dev->name_assign_type = name_assign_type; 11027 dev->group = INIT_NETDEV_GROUP; 11028 if (!dev->ethtool_ops) 11029 dev->ethtool_ops = &default_ethtool_ops; 11030 11031 nf_hook_netdev_init(dev); 11032 11033 return dev; 11034 11035 free_all: 11036 free_netdev(dev); 11037 return NULL; 11038 11039 free_pcpu: 11040 #ifdef CONFIG_PCPU_DEV_REFCNT 11041 free_percpu(dev->pcpu_refcnt); 11042 free_dev: 11043 #endif 11044 netdev_freemem(dev); 11045 return NULL; 11046 } 11047 EXPORT_SYMBOL(alloc_netdev_mqs); 11048 11049 /** 11050 * free_netdev - free network device 11051 * @dev: device 11052 * 11053 * This function does the last stage of destroying an allocated device 11054 * interface. The reference to the device object is released. If this 11055 * is the last reference then it will be freed.Must be called in process 11056 * context. 11057 */ 11058 void free_netdev(struct net_device *dev) 11059 { 11060 struct napi_struct *p, *n; 11061 11062 might_sleep(); 11063 11064 /* When called immediately after register_netdevice() failed the unwind 11065 * handling may still be dismantling the device. Handle that case by 11066 * deferring the free. 11067 */ 11068 if (dev->reg_state == NETREG_UNREGISTERING) { 11069 ASSERT_RTNL(); 11070 dev->needs_free_netdev = true; 11071 return; 11072 } 11073 11074 netif_free_tx_queues(dev); 11075 netif_free_rx_queues(dev); 11076 11077 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 11078 11079 /* Flush device addresses */ 11080 dev_addr_flush(dev); 11081 11082 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 11083 netif_napi_del(p); 11084 11085 ref_tracker_dir_exit(&dev->refcnt_tracker); 11086 #ifdef CONFIG_PCPU_DEV_REFCNT 11087 free_percpu(dev->pcpu_refcnt); 11088 dev->pcpu_refcnt = NULL; 11089 #endif 11090 free_percpu(dev->core_stats); 11091 dev->core_stats = NULL; 11092 free_percpu(dev->xdp_bulkq); 11093 dev->xdp_bulkq = NULL; 11094 11095 phy_link_topo_destroy(dev->link_topo); 11096 11097 /* Compatibility with error handling in drivers */ 11098 if (dev->reg_state == NETREG_UNINITIALIZED || 11099 dev->reg_state == NETREG_DUMMY) { 11100 netdev_freemem(dev); 11101 return; 11102 } 11103 11104 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 11105 WRITE_ONCE(dev->reg_state, NETREG_RELEASED); 11106 11107 /* will free via device release */ 11108 put_device(&dev->dev); 11109 } 11110 EXPORT_SYMBOL(free_netdev); 11111 11112 /** 11113 * alloc_netdev_dummy - Allocate and initialize a dummy net device. 11114 * @sizeof_priv: size of private data to allocate space for 11115 * 11116 * Return: the allocated net_device on success, NULL otherwise 11117 */ 11118 struct net_device *alloc_netdev_dummy(int sizeof_priv) 11119 { 11120 return alloc_netdev(sizeof_priv, "dummy#", NET_NAME_UNKNOWN, 11121 init_dummy_netdev_core); 11122 } 11123 EXPORT_SYMBOL_GPL(alloc_netdev_dummy); 11124 11125 /** 11126 * synchronize_net - Synchronize with packet receive processing 11127 * 11128 * Wait for packets currently being received to be done. 11129 * Does not block later packets from starting. 11130 */ 11131 void synchronize_net(void) 11132 { 11133 might_sleep(); 11134 if (rtnl_is_locked()) 11135 synchronize_rcu_expedited(); 11136 else 11137 synchronize_rcu(); 11138 } 11139 EXPORT_SYMBOL(synchronize_net); 11140 11141 /** 11142 * unregister_netdevice_queue - remove device from the kernel 11143 * @dev: device 11144 * @head: list 11145 * 11146 * This function shuts down a device interface and removes it 11147 * from the kernel tables. 11148 * If head not NULL, device is queued to be unregistered later. 11149 * 11150 * Callers must hold the rtnl semaphore. You may want 11151 * unregister_netdev() instead of this. 11152 */ 11153 11154 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 11155 { 11156 ASSERT_RTNL(); 11157 11158 if (head) { 11159 list_move_tail(&dev->unreg_list, head); 11160 } else { 11161 LIST_HEAD(single); 11162 11163 list_add(&dev->unreg_list, &single); 11164 unregister_netdevice_many(&single); 11165 } 11166 } 11167 EXPORT_SYMBOL(unregister_netdevice_queue); 11168 11169 void unregister_netdevice_many_notify(struct list_head *head, 11170 u32 portid, const struct nlmsghdr *nlh) 11171 { 11172 struct net_device *dev, *tmp; 11173 LIST_HEAD(close_head); 11174 int cnt = 0; 11175 11176 BUG_ON(dev_boot_phase); 11177 ASSERT_RTNL(); 11178 11179 if (list_empty(head)) 11180 return; 11181 11182 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 11183 /* Some devices call without registering 11184 * for initialization unwind. Remove those 11185 * devices and proceed with the remaining. 11186 */ 11187 if (dev->reg_state == NETREG_UNINITIALIZED) { 11188 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 11189 dev->name, dev); 11190 11191 WARN_ON(1); 11192 list_del(&dev->unreg_list); 11193 continue; 11194 } 11195 dev->dismantle = true; 11196 BUG_ON(dev->reg_state != NETREG_REGISTERED); 11197 } 11198 11199 /* If device is running, close it first. */ 11200 list_for_each_entry(dev, head, unreg_list) 11201 list_add_tail(&dev->close_list, &close_head); 11202 dev_close_many(&close_head, true); 11203 11204 list_for_each_entry(dev, head, unreg_list) { 11205 /* And unlink it from device chain. */ 11206 unlist_netdevice(dev); 11207 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERING); 11208 } 11209 flush_all_backlogs(); 11210 11211 synchronize_net(); 11212 11213 list_for_each_entry(dev, head, unreg_list) { 11214 struct sk_buff *skb = NULL; 11215 11216 /* Shutdown queueing discipline. */ 11217 dev_shutdown(dev); 11218 dev_tcx_uninstall(dev); 11219 dev_xdp_uninstall(dev); 11220 bpf_dev_bound_netdev_unregister(dev); 11221 11222 netdev_offload_xstats_disable_all(dev); 11223 11224 /* Notify protocols, that we are about to destroy 11225 * this device. They should clean all the things. 11226 */ 11227 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11228 11229 if (!dev->rtnl_link_ops || 11230 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 11231 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 11232 GFP_KERNEL, NULL, 0, 11233 portid, nlh); 11234 11235 /* 11236 * Flush the unicast and multicast chains 11237 */ 11238 dev_uc_flush(dev); 11239 dev_mc_flush(dev); 11240 11241 netdev_name_node_alt_flush(dev); 11242 netdev_name_node_free(dev->name_node); 11243 11244 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 11245 11246 if (dev->netdev_ops->ndo_uninit) 11247 dev->netdev_ops->ndo_uninit(dev); 11248 11249 if (skb) 11250 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 11251 11252 /* Notifier chain MUST detach us all upper devices. */ 11253 WARN_ON(netdev_has_any_upper_dev(dev)); 11254 WARN_ON(netdev_has_any_lower_dev(dev)); 11255 11256 /* Remove entries from kobject tree */ 11257 netdev_unregister_kobject(dev); 11258 #ifdef CONFIG_XPS 11259 /* Remove XPS queueing entries */ 11260 netif_reset_xps_queues_gt(dev, 0); 11261 #endif 11262 } 11263 11264 synchronize_net(); 11265 11266 list_for_each_entry(dev, head, unreg_list) { 11267 netdev_put(dev, &dev->dev_registered_tracker); 11268 net_set_todo(dev); 11269 cnt++; 11270 } 11271 atomic_add(cnt, &dev_unreg_count); 11272 11273 list_del(head); 11274 } 11275 11276 /** 11277 * unregister_netdevice_many - unregister many devices 11278 * @head: list of devices 11279 * 11280 * Note: As most callers use a stack allocated list_head, 11281 * we force a list_del() to make sure stack wont be corrupted later. 11282 */ 11283 void unregister_netdevice_many(struct list_head *head) 11284 { 11285 unregister_netdevice_many_notify(head, 0, NULL); 11286 } 11287 EXPORT_SYMBOL(unregister_netdevice_many); 11288 11289 /** 11290 * unregister_netdev - remove device from the kernel 11291 * @dev: device 11292 * 11293 * This function shuts down a device interface and removes it 11294 * from the kernel tables. 11295 * 11296 * This is just a wrapper for unregister_netdevice that takes 11297 * the rtnl semaphore. In general you want to use this and not 11298 * unregister_netdevice. 11299 */ 11300 void unregister_netdev(struct net_device *dev) 11301 { 11302 rtnl_lock(); 11303 unregister_netdevice(dev); 11304 rtnl_unlock(); 11305 } 11306 EXPORT_SYMBOL(unregister_netdev); 11307 11308 /** 11309 * __dev_change_net_namespace - move device to different nethost namespace 11310 * @dev: device 11311 * @net: network namespace 11312 * @pat: If not NULL name pattern to try if the current device name 11313 * is already taken in the destination network namespace. 11314 * @new_ifindex: If not zero, specifies device index in the target 11315 * namespace. 11316 * 11317 * This function shuts down a device interface and moves it 11318 * to a new network namespace. On success 0 is returned, on 11319 * a failure a netagive errno code is returned. 11320 * 11321 * Callers must hold the rtnl semaphore. 11322 */ 11323 11324 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 11325 const char *pat, int new_ifindex) 11326 { 11327 struct netdev_name_node *name_node; 11328 struct net *net_old = dev_net(dev); 11329 char new_name[IFNAMSIZ] = {}; 11330 int err, new_nsid; 11331 11332 ASSERT_RTNL(); 11333 11334 /* Don't allow namespace local devices to be moved. */ 11335 err = -EINVAL; 11336 if (dev->features & NETIF_F_NETNS_LOCAL) 11337 goto out; 11338 11339 /* Ensure the device has been registrered */ 11340 if (dev->reg_state != NETREG_REGISTERED) 11341 goto out; 11342 11343 /* Get out if there is nothing todo */ 11344 err = 0; 11345 if (net_eq(net_old, net)) 11346 goto out; 11347 11348 /* Pick the destination device name, and ensure 11349 * we can use it in the destination network namespace. 11350 */ 11351 err = -EEXIST; 11352 if (netdev_name_in_use(net, dev->name)) { 11353 /* We get here if we can't use the current device name */ 11354 if (!pat) 11355 goto out; 11356 err = dev_prep_valid_name(net, dev, pat, new_name, EEXIST); 11357 if (err < 0) 11358 goto out; 11359 } 11360 /* Check that none of the altnames conflicts. */ 11361 err = -EEXIST; 11362 netdev_for_each_altname(dev, name_node) 11363 if (netdev_name_in_use(net, name_node->name)) 11364 goto out; 11365 11366 /* Check that new_ifindex isn't used yet. */ 11367 if (new_ifindex) { 11368 err = dev_index_reserve(net, new_ifindex); 11369 if (err < 0) 11370 goto out; 11371 } else { 11372 /* If there is an ifindex conflict assign a new one */ 11373 err = dev_index_reserve(net, dev->ifindex); 11374 if (err == -EBUSY) 11375 err = dev_index_reserve(net, 0); 11376 if (err < 0) 11377 goto out; 11378 new_ifindex = err; 11379 } 11380 11381 /* 11382 * And now a mini version of register_netdevice unregister_netdevice. 11383 */ 11384 11385 /* If device is running close it first. */ 11386 dev_close(dev); 11387 11388 /* And unlink it from device chain */ 11389 unlist_netdevice(dev); 11390 11391 synchronize_net(); 11392 11393 /* Shutdown queueing discipline. */ 11394 dev_shutdown(dev); 11395 11396 /* Notify protocols, that we are about to destroy 11397 * this device. They should clean all the things. 11398 * 11399 * Note that dev->reg_state stays at NETREG_REGISTERED. 11400 * This is wanted because this way 8021q and macvlan know 11401 * the device is just moving and can keep their slaves up. 11402 */ 11403 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11404 rcu_barrier(); 11405 11406 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 11407 11408 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 11409 new_ifindex); 11410 11411 /* 11412 * Flush the unicast and multicast chains 11413 */ 11414 dev_uc_flush(dev); 11415 dev_mc_flush(dev); 11416 11417 /* Send a netdev-removed uevent to the old namespace */ 11418 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 11419 netdev_adjacent_del_links(dev); 11420 11421 /* Move per-net netdevice notifiers that are following the netdevice */ 11422 move_netdevice_notifiers_dev_net(dev, net); 11423 11424 /* Actually switch the network namespace */ 11425 dev_net_set(dev, net); 11426 dev->ifindex = new_ifindex; 11427 11428 if (new_name[0]) { 11429 /* Rename the netdev to prepared name */ 11430 write_seqlock(&netdev_rename_lock); 11431 strscpy(dev->name, new_name, IFNAMSIZ); 11432 write_sequnlock(&netdev_rename_lock); 11433 } 11434 11435 /* Fixup kobjects */ 11436 dev_set_uevent_suppress(&dev->dev, 1); 11437 err = device_rename(&dev->dev, dev->name); 11438 dev_set_uevent_suppress(&dev->dev, 0); 11439 WARN_ON(err); 11440 11441 /* Send a netdev-add uevent to the new namespace */ 11442 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 11443 netdev_adjacent_add_links(dev); 11444 11445 /* Adapt owner in case owning user namespace of target network 11446 * namespace is different from the original one. 11447 */ 11448 err = netdev_change_owner(dev, net_old, net); 11449 WARN_ON(err); 11450 11451 /* Add the device back in the hashes */ 11452 list_netdevice(dev); 11453 11454 /* Notify protocols, that a new device appeared. */ 11455 call_netdevice_notifiers(NETDEV_REGISTER, dev); 11456 11457 /* 11458 * Prevent userspace races by waiting until the network 11459 * device is fully setup before sending notifications. 11460 */ 11461 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 11462 11463 synchronize_net(); 11464 err = 0; 11465 out: 11466 return err; 11467 } 11468 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 11469 11470 static int dev_cpu_dead(unsigned int oldcpu) 11471 { 11472 struct sk_buff **list_skb; 11473 struct sk_buff *skb; 11474 unsigned int cpu; 11475 struct softnet_data *sd, *oldsd, *remsd = NULL; 11476 11477 local_irq_disable(); 11478 cpu = smp_processor_id(); 11479 sd = &per_cpu(softnet_data, cpu); 11480 oldsd = &per_cpu(softnet_data, oldcpu); 11481 11482 /* Find end of our completion_queue. */ 11483 list_skb = &sd->completion_queue; 11484 while (*list_skb) 11485 list_skb = &(*list_skb)->next; 11486 /* Append completion queue from offline CPU. */ 11487 *list_skb = oldsd->completion_queue; 11488 oldsd->completion_queue = NULL; 11489 11490 /* Append output queue from offline CPU. */ 11491 if (oldsd->output_queue) { 11492 *sd->output_queue_tailp = oldsd->output_queue; 11493 sd->output_queue_tailp = oldsd->output_queue_tailp; 11494 oldsd->output_queue = NULL; 11495 oldsd->output_queue_tailp = &oldsd->output_queue; 11496 } 11497 /* Append NAPI poll list from offline CPU, with one exception : 11498 * process_backlog() must be called by cpu owning percpu backlog. 11499 * We properly handle process_queue & input_pkt_queue later. 11500 */ 11501 while (!list_empty(&oldsd->poll_list)) { 11502 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 11503 struct napi_struct, 11504 poll_list); 11505 11506 list_del_init(&napi->poll_list); 11507 if (napi->poll == process_backlog) 11508 napi->state &= NAPIF_STATE_THREADED; 11509 else 11510 ____napi_schedule(sd, napi); 11511 } 11512 11513 raise_softirq_irqoff(NET_TX_SOFTIRQ); 11514 local_irq_enable(); 11515 11516 if (!use_backlog_threads()) { 11517 #ifdef CONFIG_RPS 11518 remsd = oldsd->rps_ipi_list; 11519 oldsd->rps_ipi_list = NULL; 11520 #endif 11521 /* send out pending IPI's on offline CPU */ 11522 net_rps_send_ipi(remsd); 11523 } 11524 11525 /* Process offline CPU's input_pkt_queue */ 11526 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 11527 netif_rx(skb); 11528 rps_input_queue_head_incr(oldsd); 11529 } 11530 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 11531 netif_rx(skb); 11532 rps_input_queue_head_incr(oldsd); 11533 } 11534 11535 return 0; 11536 } 11537 11538 /** 11539 * netdev_increment_features - increment feature set by one 11540 * @all: current feature set 11541 * @one: new feature set 11542 * @mask: mask feature set 11543 * 11544 * Computes a new feature set after adding a device with feature set 11545 * @one to the master device with current feature set @all. Will not 11546 * enable anything that is off in @mask. Returns the new feature set. 11547 */ 11548 netdev_features_t netdev_increment_features(netdev_features_t all, 11549 netdev_features_t one, netdev_features_t mask) 11550 { 11551 if (mask & NETIF_F_HW_CSUM) 11552 mask |= NETIF_F_CSUM_MASK; 11553 mask |= NETIF_F_VLAN_CHALLENGED; 11554 11555 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 11556 all &= one | ~NETIF_F_ALL_FOR_ALL; 11557 11558 /* If one device supports hw checksumming, set for all. */ 11559 if (all & NETIF_F_HW_CSUM) 11560 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 11561 11562 return all; 11563 } 11564 EXPORT_SYMBOL(netdev_increment_features); 11565 11566 static struct hlist_head * __net_init netdev_create_hash(void) 11567 { 11568 int i; 11569 struct hlist_head *hash; 11570 11571 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 11572 if (hash != NULL) 11573 for (i = 0; i < NETDEV_HASHENTRIES; i++) 11574 INIT_HLIST_HEAD(&hash[i]); 11575 11576 return hash; 11577 } 11578 11579 /* Initialize per network namespace state */ 11580 static int __net_init netdev_init(struct net *net) 11581 { 11582 BUILD_BUG_ON(GRO_HASH_BUCKETS > 11583 8 * sizeof_field(struct napi_struct, gro_bitmask)); 11584 11585 INIT_LIST_HEAD(&net->dev_base_head); 11586 11587 net->dev_name_head = netdev_create_hash(); 11588 if (net->dev_name_head == NULL) 11589 goto err_name; 11590 11591 net->dev_index_head = netdev_create_hash(); 11592 if (net->dev_index_head == NULL) 11593 goto err_idx; 11594 11595 xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1); 11596 11597 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 11598 11599 return 0; 11600 11601 err_idx: 11602 kfree(net->dev_name_head); 11603 err_name: 11604 return -ENOMEM; 11605 } 11606 11607 /** 11608 * netdev_drivername - network driver for the device 11609 * @dev: network device 11610 * 11611 * Determine network driver for device. 11612 */ 11613 const char *netdev_drivername(const struct net_device *dev) 11614 { 11615 const struct device_driver *driver; 11616 const struct device *parent; 11617 const char *empty = ""; 11618 11619 parent = dev->dev.parent; 11620 if (!parent) 11621 return empty; 11622 11623 driver = parent->driver; 11624 if (driver && driver->name) 11625 return driver->name; 11626 return empty; 11627 } 11628 11629 static void __netdev_printk(const char *level, const struct net_device *dev, 11630 struct va_format *vaf) 11631 { 11632 if (dev && dev->dev.parent) { 11633 dev_printk_emit(level[1] - '0', 11634 dev->dev.parent, 11635 "%s %s %s%s: %pV", 11636 dev_driver_string(dev->dev.parent), 11637 dev_name(dev->dev.parent), 11638 netdev_name(dev), netdev_reg_state(dev), 11639 vaf); 11640 } else if (dev) { 11641 printk("%s%s%s: %pV", 11642 level, netdev_name(dev), netdev_reg_state(dev), vaf); 11643 } else { 11644 printk("%s(NULL net_device): %pV", level, vaf); 11645 } 11646 } 11647 11648 void netdev_printk(const char *level, const struct net_device *dev, 11649 const char *format, ...) 11650 { 11651 struct va_format vaf; 11652 va_list args; 11653 11654 va_start(args, format); 11655 11656 vaf.fmt = format; 11657 vaf.va = &args; 11658 11659 __netdev_printk(level, dev, &vaf); 11660 11661 va_end(args); 11662 } 11663 EXPORT_SYMBOL(netdev_printk); 11664 11665 #define define_netdev_printk_level(func, level) \ 11666 void func(const struct net_device *dev, const char *fmt, ...) \ 11667 { \ 11668 struct va_format vaf; \ 11669 va_list args; \ 11670 \ 11671 va_start(args, fmt); \ 11672 \ 11673 vaf.fmt = fmt; \ 11674 vaf.va = &args; \ 11675 \ 11676 __netdev_printk(level, dev, &vaf); \ 11677 \ 11678 va_end(args); \ 11679 } \ 11680 EXPORT_SYMBOL(func); 11681 11682 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 11683 define_netdev_printk_level(netdev_alert, KERN_ALERT); 11684 define_netdev_printk_level(netdev_crit, KERN_CRIT); 11685 define_netdev_printk_level(netdev_err, KERN_ERR); 11686 define_netdev_printk_level(netdev_warn, KERN_WARNING); 11687 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 11688 define_netdev_printk_level(netdev_info, KERN_INFO); 11689 11690 static void __net_exit netdev_exit(struct net *net) 11691 { 11692 kfree(net->dev_name_head); 11693 kfree(net->dev_index_head); 11694 xa_destroy(&net->dev_by_index); 11695 if (net != &init_net) 11696 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 11697 } 11698 11699 static struct pernet_operations __net_initdata netdev_net_ops = { 11700 .init = netdev_init, 11701 .exit = netdev_exit, 11702 }; 11703 11704 static void __net_exit default_device_exit_net(struct net *net) 11705 { 11706 struct netdev_name_node *name_node, *tmp; 11707 struct net_device *dev, *aux; 11708 /* 11709 * Push all migratable network devices back to the 11710 * initial network namespace 11711 */ 11712 ASSERT_RTNL(); 11713 for_each_netdev_safe(net, dev, aux) { 11714 int err; 11715 char fb_name[IFNAMSIZ]; 11716 11717 /* Ignore unmoveable devices (i.e. loopback) */ 11718 if (dev->features & NETIF_F_NETNS_LOCAL) 11719 continue; 11720 11721 /* Leave virtual devices for the generic cleanup */ 11722 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 11723 continue; 11724 11725 /* Push remaining network devices to init_net */ 11726 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 11727 if (netdev_name_in_use(&init_net, fb_name)) 11728 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 11729 11730 netdev_for_each_altname_safe(dev, name_node, tmp) 11731 if (netdev_name_in_use(&init_net, name_node->name)) 11732 __netdev_name_node_alt_destroy(name_node); 11733 11734 err = dev_change_net_namespace(dev, &init_net, fb_name); 11735 if (err) { 11736 pr_emerg("%s: failed to move %s to init_net: %d\n", 11737 __func__, dev->name, err); 11738 BUG(); 11739 } 11740 } 11741 } 11742 11743 static void __net_exit default_device_exit_batch(struct list_head *net_list) 11744 { 11745 /* At exit all network devices most be removed from a network 11746 * namespace. Do this in the reverse order of registration. 11747 * Do this across as many network namespaces as possible to 11748 * improve batching efficiency. 11749 */ 11750 struct net_device *dev; 11751 struct net *net; 11752 LIST_HEAD(dev_kill_list); 11753 11754 rtnl_lock(); 11755 list_for_each_entry(net, net_list, exit_list) { 11756 default_device_exit_net(net); 11757 cond_resched(); 11758 } 11759 11760 list_for_each_entry(net, net_list, exit_list) { 11761 for_each_netdev_reverse(net, dev) { 11762 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 11763 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 11764 else 11765 unregister_netdevice_queue(dev, &dev_kill_list); 11766 } 11767 } 11768 unregister_netdevice_many(&dev_kill_list); 11769 rtnl_unlock(); 11770 } 11771 11772 static struct pernet_operations __net_initdata default_device_ops = { 11773 .exit_batch = default_device_exit_batch, 11774 }; 11775 11776 static void __init net_dev_struct_check(void) 11777 { 11778 /* TX read-mostly hotpath */ 11779 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, priv_flags); 11780 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, netdev_ops); 11781 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, header_ops); 11782 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, _tx); 11783 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, real_num_tx_queues); 11784 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_size); 11785 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_ipv4_max_size); 11786 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_segs); 11787 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_partial_features); 11788 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, num_tc); 11789 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, mtu); 11790 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, needed_headroom); 11791 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tc_to_txq); 11792 #ifdef CONFIG_XPS 11793 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, xps_maps); 11794 #endif 11795 #ifdef CONFIG_NETFILTER_EGRESS 11796 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, nf_hooks_egress); 11797 #endif 11798 #ifdef CONFIG_NET_XGRESS 11799 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tcx_egress); 11800 #endif 11801 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_tx, 160); 11802 11803 /* TXRX read-mostly hotpath */ 11804 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, lstats); 11805 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, state); 11806 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, flags); 11807 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, hard_header_len); 11808 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, features); 11809 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, ip6_ptr); 11810 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 46); 11811 11812 /* RX read-mostly hotpath */ 11813 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ptype_specific); 11814 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ifindex); 11815 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real_num_rx_queues); 11816 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx); 11817 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_flush_timeout); 11818 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, napi_defer_hard_irqs); 11819 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_max_size); 11820 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_ipv4_max_size); 11821 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler); 11822 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler_data); 11823 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, nd_net); 11824 #ifdef CONFIG_NETPOLL 11825 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, npinfo); 11826 #endif 11827 #ifdef CONFIG_NET_XGRESS 11828 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_ingress); 11829 #endif 11830 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 104); 11831 } 11832 11833 /* 11834 * Initialize the DEV module. At boot time this walks the device list and 11835 * unhooks any devices that fail to initialise (normally hardware not 11836 * present) and leaves us with a valid list of present and active devices. 11837 * 11838 */ 11839 11840 /* We allocate 256 pages for each CPU if PAGE_SHIFT is 12 */ 11841 #define SYSTEM_PERCPU_PAGE_POOL_SIZE ((1 << 20) / PAGE_SIZE) 11842 11843 static int net_page_pool_create(int cpuid) 11844 { 11845 #if IS_ENABLED(CONFIG_PAGE_POOL) 11846 struct page_pool_params page_pool_params = { 11847 .pool_size = SYSTEM_PERCPU_PAGE_POOL_SIZE, 11848 .flags = PP_FLAG_SYSTEM_POOL, 11849 .nid = cpu_to_mem(cpuid), 11850 }; 11851 struct page_pool *pp_ptr; 11852 11853 pp_ptr = page_pool_create_percpu(&page_pool_params, cpuid); 11854 if (IS_ERR(pp_ptr)) 11855 return -ENOMEM; 11856 11857 per_cpu(system_page_pool, cpuid) = pp_ptr; 11858 #endif 11859 return 0; 11860 } 11861 11862 static int backlog_napi_should_run(unsigned int cpu) 11863 { 11864 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 11865 struct napi_struct *napi = &sd->backlog; 11866 11867 return test_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 11868 } 11869 11870 static void run_backlog_napi(unsigned int cpu) 11871 { 11872 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 11873 11874 napi_threaded_poll_loop(&sd->backlog); 11875 } 11876 11877 static void backlog_napi_setup(unsigned int cpu) 11878 { 11879 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 11880 struct napi_struct *napi = &sd->backlog; 11881 11882 napi->thread = this_cpu_read(backlog_napi); 11883 set_bit(NAPI_STATE_THREADED, &napi->state); 11884 } 11885 11886 static struct smp_hotplug_thread backlog_threads = { 11887 .store = &backlog_napi, 11888 .thread_should_run = backlog_napi_should_run, 11889 .thread_fn = run_backlog_napi, 11890 .thread_comm = "backlog_napi/%u", 11891 .setup = backlog_napi_setup, 11892 }; 11893 11894 /* 11895 * This is called single threaded during boot, so no need 11896 * to take the rtnl semaphore. 11897 */ 11898 static int __init net_dev_init(void) 11899 { 11900 int i, rc = -ENOMEM; 11901 11902 BUG_ON(!dev_boot_phase); 11903 11904 net_dev_struct_check(); 11905 11906 if (dev_proc_init()) 11907 goto out; 11908 11909 if (netdev_kobject_init()) 11910 goto out; 11911 11912 for (i = 0; i < PTYPE_HASH_SIZE; i++) 11913 INIT_LIST_HEAD(&ptype_base[i]); 11914 11915 if (register_pernet_subsys(&netdev_net_ops)) 11916 goto out; 11917 11918 /* 11919 * Initialise the packet receive queues. 11920 */ 11921 11922 for_each_possible_cpu(i) { 11923 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 11924 struct softnet_data *sd = &per_cpu(softnet_data, i); 11925 11926 INIT_WORK(flush, flush_backlog); 11927 11928 skb_queue_head_init(&sd->input_pkt_queue); 11929 skb_queue_head_init(&sd->process_queue); 11930 #ifdef CONFIG_XFRM_OFFLOAD 11931 skb_queue_head_init(&sd->xfrm_backlog); 11932 #endif 11933 INIT_LIST_HEAD(&sd->poll_list); 11934 sd->output_queue_tailp = &sd->output_queue; 11935 #ifdef CONFIG_RPS 11936 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11937 sd->cpu = i; 11938 #endif 11939 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 11940 spin_lock_init(&sd->defer_lock); 11941 11942 init_gro_hash(&sd->backlog); 11943 sd->backlog.poll = process_backlog; 11944 sd->backlog.weight = weight_p; 11945 INIT_LIST_HEAD(&sd->backlog.poll_list); 11946 11947 if (net_page_pool_create(i)) 11948 goto out; 11949 } 11950 if (use_backlog_threads()) 11951 smpboot_register_percpu_thread(&backlog_threads); 11952 11953 dev_boot_phase = 0; 11954 11955 /* The loopback device is special if any other network devices 11956 * is present in a network namespace the loopback device must 11957 * be present. Since we now dynamically allocate and free the 11958 * loopback device ensure this invariant is maintained by 11959 * keeping the loopback device as the first device on the 11960 * list of network devices. Ensuring the loopback devices 11961 * is the first device that appears and the last network device 11962 * that disappears. 11963 */ 11964 if (register_pernet_device(&loopback_net_ops)) 11965 goto out; 11966 11967 if (register_pernet_device(&default_device_ops)) 11968 goto out; 11969 11970 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11971 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11972 11973 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11974 NULL, dev_cpu_dead); 11975 WARN_ON(rc < 0); 11976 rc = 0; 11977 11978 /* avoid static key IPIs to isolated CPUs */ 11979 if (housekeeping_enabled(HK_TYPE_MISC)) 11980 net_enable_timestamp(); 11981 out: 11982 if (rc < 0) { 11983 for_each_possible_cpu(i) { 11984 struct page_pool *pp_ptr; 11985 11986 pp_ptr = per_cpu(system_page_pool, i); 11987 if (!pp_ptr) 11988 continue; 11989 11990 page_pool_destroy(pp_ptr); 11991 per_cpu(system_page_pool, i) = NULL; 11992 } 11993 } 11994 11995 return rc; 11996 } 11997 11998 subsys_initcall(net_dev_init); 11999