1 /* 2 * NET3 Protocol independent device support routines. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Derived from the non IP parts of dev.c 1.0.19 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <[email protected]> 12 * Mark Evans, <[email protected]> 13 * 14 * Additional Authors: 15 * Florian la Roche <[email protected]> 16 * Alan Cox <[email protected]> 17 * David Hinds <[email protected]> 18 * Alexey Kuznetsov <[email protected]> 19 * Adam Sulmicki <[email protected]> 20 * Pekka Riikonen <[email protected]> 21 * 22 * Changes: 23 * D.J. Barrow : Fixed bug where dev->refcnt gets set 24 * to 2 if register_netdev gets called 25 * before net_dev_init & also removed a 26 * few lines of code in the process. 27 * Alan Cox : device private ioctl copies fields back. 28 * Alan Cox : Transmit queue code does relevant 29 * stunts to keep the queue safe. 30 * Alan Cox : Fixed double lock. 31 * Alan Cox : Fixed promisc NULL pointer trap 32 * ???????? : Support the full private ioctl range 33 * Alan Cox : Moved ioctl permission check into 34 * drivers 35 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 36 * Alan Cox : 100 backlog just doesn't cut it when 37 * you start doing multicast video 8) 38 * Alan Cox : Rewrote net_bh and list manager. 39 * Alan Cox : Fix ETH_P_ALL echoback lengths. 40 * Alan Cox : Took out transmit every packet pass 41 * Saved a few bytes in the ioctl handler 42 * Alan Cox : Network driver sets packet type before 43 * calling netif_rx. Saves a function 44 * call a packet. 45 * Alan Cox : Hashed net_bh() 46 * Richard Kooijman: Timestamp fixes. 47 * Alan Cox : Wrong field in SIOCGIFDSTADDR 48 * Alan Cox : Device lock protection. 49 * Alan Cox : Fixed nasty side effect of device close 50 * changes. 51 * Rudi Cilibrasi : Pass the right thing to 52 * set_mac_address() 53 * Dave Miller : 32bit quantity for the device lock to 54 * make it work out on a Sparc. 55 * Bjorn Ekwall : Added KERNELD hack. 56 * Alan Cox : Cleaned up the backlog initialise. 57 * Craig Metz : SIOCGIFCONF fix if space for under 58 * 1 device. 59 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 60 * is no device open function. 61 * Andi Kleen : Fix error reporting for SIOCGIFCONF 62 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 63 * Cyrus Durgin : Cleaned for KMOD 64 * Adam Sulmicki : Bug Fix : Network Device Unload 65 * A network device unload needs to purge 66 * the backlog queue. 67 * Paul Rusty Russell : SIOCSIFNAME 68 * Pekka Riikonen : Netdev boot-time settings code 69 * Andrew Morton : Make unregister_netdevice wait 70 * indefinitely on dev->refcnt 71 * J Hadi Salim : - Backlog queue sampling 72 * - netif_rx() feedback 73 */ 74 75 #include <asm/uaccess.h> 76 #include <asm/system.h> 77 #include <linux/bitops.h> 78 #include <linux/capability.h> 79 #include <linux/cpu.h> 80 #include <linux/types.h> 81 #include <linux/kernel.h> 82 #include <linux/hash.h> 83 #include <linux/slab.h> 84 #include <linux/sched.h> 85 #include <linux/mutex.h> 86 #include <linux/string.h> 87 #include <linux/mm.h> 88 #include <linux/socket.h> 89 #include <linux/sockios.h> 90 #include <linux/errno.h> 91 #include <linux/interrupt.h> 92 #include <linux/if_ether.h> 93 #include <linux/netdevice.h> 94 #include <linux/etherdevice.h> 95 #include <linux/ethtool.h> 96 #include <linux/notifier.h> 97 #include <linux/skbuff.h> 98 #include <net/net_namespace.h> 99 #include <net/sock.h> 100 #include <linux/rtnetlink.h> 101 #include <linux/proc_fs.h> 102 #include <linux/seq_file.h> 103 #include <linux/stat.h> 104 #include <net/dst.h> 105 #include <net/pkt_sched.h> 106 #include <net/checksum.h> 107 #include <net/xfrm.h> 108 #include <linux/highmem.h> 109 #include <linux/init.h> 110 #include <linux/kmod.h> 111 #include <linux/module.h> 112 #include <linux/netpoll.h> 113 #include <linux/rcupdate.h> 114 #include <linux/delay.h> 115 #include <net/wext.h> 116 #include <net/iw_handler.h> 117 #include <asm/current.h> 118 #include <linux/audit.h> 119 #include <linux/dmaengine.h> 120 #include <linux/err.h> 121 #include <linux/ctype.h> 122 #include <linux/if_arp.h> 123 #include <linux/if_vlan.h> 124 #include <linux/ip.h> 125 #include <net/ip.h> 126 #include <linux/ipv6.h> 127 #include <linux/in.h> 128 #include <linux/jhash.h> 129 #include <linux/random.h> 130 #include <trace/events/napi.h> 131 #include <trace/events/net.h> 132 #include <trace/events/skb.h> 133 #include <linux/pci.h> 134 #include <linux/inetdevice.h> 135 #include <linux/cpu_rmap.h> 136 137 #include "net-sysfs.h" 138 139 /* Instead of increasing this, you should create a hash table. */ 140 #define MAX_GRO_SKBS 8 141 142 /* This should be increased if a protocol with a bigger head is added. */ 143 #define GRO_MAX_HEAD (MAX_HEADER + 128) 144 145 /* 146 * The list of packet types we will receive (as opposed to discard) 147 * and the routines to invoke. 148 * 149 * Why 16. Because with 16 the only overlap we get on a hash of the 150 * low nibble of the protocol value is RARP/SNAP/X.25. 151 * 152 * NOTE: That is no longer true with the addition of VLAN tags. Not 153 * sure which should go first, but I bet it won't make much 154 * difference if we are running VLANs. The good news is that 155 * this protocol won't be in the list unless compiled in, so 156 * the average user (w/out VLANs) will not be adversely affected. 157 * --BLG 158 * 159 * 0800 IP 160 * 8100 802.1Q VLAN 161 * 0001 802.3 162 * 0002 AX.25 163 * 0004 802.2 164 * 8035 RARP 165 * 0005 SNAP 166 * 0805 X.25 167 * 0806 ARP 168 * 8137 IPX 169 * 0009 Localtalk 170 * 86DD IPv6 171 */ 172 173 #define PTYPE_HASH_SIZE (16) 174 #define PTYPE_HASH_MASK (PTYPE_HASH_SIZE - 1) 175 176 static DEFINE_SPINLOCK(ptype_lock); 177 static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 178 static struct list_head ptype_all __read_mostly; /* Taps */ 179 180 /* 181 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 182 * semaphore. 183 * 184 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 185 * 186 * Writers must hold the rtnl semaphore while they loop through the 187 * dev_base_head list, and hold dev_base_lock for writing when they do the 188 * actual updates. This allows pure readers to access the list even 189 * while a writer is preparing to update it. 190 * 191 * To put it another way, dev_base_lock is held for writing only to 192 * protect against pure readers; the rtnl semaphore provides the 193 * protection against other writers. 194 * 195 * See, for example usages, register_netdevice() and 196 * unregister_netdevice(), which must be called with the rtnl 197 * semaphore held. 198 */ 199 DEFINE_RWLOCK(dev_base_lock); 200 EXPORT_SYMBOL(dev_base_lock); 201 202 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 203 { 204 unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ)); 205 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 206 } 207 208 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 209 { 210 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 211 } 212 213 static inline void rps_lock(struct softnet_data *sd) 214 { 215 #ifdef CONFIG_RPS 216 spin_lock(&sd->input_pkt_queue.lock); 217 #endif 218 } 219 220 static inline void rps_unlock(struct softnet_data *sd) 221 { 222 #ifdef CONFIG_RPS 223 spin_unlock(&sd->input_pkt_queue.lock); 224 #endif 225 } 226 227 /* Device list insertion */ 228 static int list_netdevice(struct net_device *dev) 229 { 230 struct net *net = dev_net(dev); 231 232 ASSERT_RTNL(); 233 234 write_lock_bh(&dev_base_lock); 235 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 236 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 237 hlist_add_head_rcu(&dev->index_hlist, 238 dev_index_hash(net, dev->ifindex)); 239 write_unlock_bh(&dev_base_lock); 240 return 0; 241 } 242 243 /* Device list removal 244 * caller must respect a RCU grace period before freeing/reusing dev 245 */ 246 static void unlist_netdevice(struct net_device *dev) 247 { 248 ASSERT_RTNL(); 249 250 /* Unlink dev from the device chain */ 251 write_lock_bh(&dev_base_lock); 252 list_del_rcu(&dev->dev_list); 253 hlist_del_rcu(&dev->name_hlist); 254 hlist_del_rcu(&dev->index_hlist); 255 write_unlock_bh(&dev_base_lock); 256 } 257 258 /* 259 * Our notifier list 260 */ 261 262 static RAW_NOTIFIER_HEAD(netdev_chain); 263 264 /* 265 * Device drivers call our routines to queue packets here. We empty the 266 * queue in the local softnet handler. 267 */ 268 269 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 270 EXPORT_PER_CPU_SYMBOL(softnet_data); 271 272 #ifdef CONFIG_LOCKDEP 273 /* 274 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 275 * according to dev->type 276 */ 277 static const unsigned short netdev_lock_type[] = 278 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 279 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 280 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 281 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 282 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 283 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 284 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 285 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 286 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 287 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 288 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 289 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 290 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211, 291 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, 292 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154, 293 ARPHRD_VOID, ARPHRD_NONE}; 294 295 static const char *const netdev_lock_name[] = 296 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 297 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 298 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 299 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 300 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 301 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 302 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 303 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 304 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 305 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 306 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 307 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 308 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211", 309 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", 310 "_xmit_PHONET_PIPE", "_xmit_IEEE802154", 311 "_xmit_VOID", "_xmit_NONE"}; 312 313 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 314 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 315 316 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 317 { 318 int i; 319 320 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 321 if (netdev_lock_type[i] == dev_type) 322 return i; 323 /* the last key is used by default */ 324 return ARRAY_SIZE(netdev_lock_type) - 1; 325 } 326 327 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 328 unsigned short dev_type) 329 { 330 int i; 331 332 i = netdev_lock_pos(dev_type); 333 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 334 netdev_lock_name[i]); 335 } 336 337 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 338 { 339 int i; 340 341 i = netdev_lock_pos(dev->type); 342 lockdep_set_class_and_name(&dev->addr_list_lock, 343 &netdev_addr_lock_key[i], 344 netdev_lock_name[i]); 345 } 346 #else 347 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 348 unsigned short dev_type) 349 { 350 } 351 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 352 { 353 } 354 #endif 355 356 /******************************************************************************* 357 358 Protocol management and registration routines 359 360 *******************************************************************************/ 361 362 /* 363 * Add a protocol ID to the list. Now that the input handler is 364 * smarter we can dispense with all the messy stuff that used to be 365 * here. 366 * 367 * BEWARE!!! Protocol handlers, mangling input packets, 368 * MUST BE last in hash buckets and checking protocol handlers 369 * MUST start from promiscuous ptype_all chain in net_bh. 370 * It is true now, do not change it. 371 * Explanation follows: if protocol handler, mangling packet, will 372 * be the first on list, it is not able to sense, that packet 373 * is cloned and should be copied-on-write, so that it will 374 * change it and subsequent readers will get broken packet. 375 * --ANK (980803) 376 */ 377 378 static inline struct list_head *ptype_head(const struct packet_type *pt) 379 { 380 if (pt->type == htons(ETH_P_ALL)) 381 return &ptype_all; 382 else 383 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 384 } 385 386 /** 387 * dev_add_pack - add packet handler 388 * @pt: packet type declaration 389 * 390 * Add a protocol handler to the networking stack. The passed &packet_type 391 * is linked into kernel lists and may not be freed until it has been 392 * removed from the kernel lists. 393 * 394 * This call does not sleep therefore it can not 395 * guarantee all CPU's that are in middle of receiving packets 396 * will see the new packet type (until the next received packet). 397 */ 398 399 void dev_add_pack(struct packet_type *pt) 400 { 401 struct list_head *head = ptype_head(pt); 402 403 spin_lock(&ptype_lock); 404 list_add_rcu(&pt->list, head); 405 spin_unlock(&ptype_lock); 406 } 407 EXPORT_SYMBOL(dev_add_pack); 408 409 /** 410 * __dev_remove_pack - remove packet handler 411 * @pt: packet type declaration 412 * 413 * Remove a protocol handler that was previously added to the kernel 414 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 415 * from the kernel lists and can be freed or reused once this function 416 * returns. 417 * 418 * The packet type might still be in use by receivers 419 * and must not be freed until after all the CPU's have gone 420 * through a quiescent state. 421 */ 422 void __dev_remove_pack(struct packet_type *pt) 423 { 424 struct list_head *head = ptype_head(pt); 425 struct packet_type *pt1; 426 427 spin_lock(&ptype_lock); 428 429 list_for_each_entry(pt1, head, list) { 430 if (pt == pt1) { 431 list_del_rcu(&pt->list); 432 goto out; 433 } 434 } 435 436 printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt); 437 out: 438 spin_unlock(&ptype_lock); 439 } 440 EXPORT_SYMBOL(__dev_remove_pack); 441 442 /** 443 * dev_remove_pack - remove packet handler 444 * @pt: packet type declaration 445 * 446 * Remove a protocol handler that was previously added to the kernel 447 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 448 * from the kernel lists and can be freed or reused once this function 449 * returns. 450 * 451 * This call sleeps to guarantee that no CPU is looking at the packet 452 * type after return. 453 */ 454 void dev_remove_pack(struct packet_type *pt) 455 { 456 __dev_remove_pack(pt); 457 458 synchronize_net(); 459 } 460 EXPORT_SYMBOL(dev_remove_pack); 461 462 /****************************************************************************** 463 464 Device Boot-time Settings Routines 465 466 *******************************************************************************/ 467 468 /* Boot time configuration table */ 469 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; 470 471 /** 472 * netdev_boot_setup_add - add new setup entry 473 * @name: name of the device 474 * @map: configured settings for the device 475 * 476 * Adds new setup entry to the dev_boot_setup list. The function 477 * returns 0 on error and 1 on success. This is a generic routine to 478 * all netdevices. 479 */ 480 static int netdev_boot_setup_add(char *name, struct ifmap *map) 481 { 482 struct netdev_boot_setup *s; 483 int i; 484 485 s = dev_boot_setup; 486 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 487 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { 488 memset(s[i].name, 0, sizeof(s[i].name)); 489 strlcpy(s[i].name, name, IFNAMSIZ); 490 memcpy(&s[i].map, map, sizeof(s[i].map)); 491 break; 492 } 493 } 494 495 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; 496 } 497 498 /** 499 * netdev_boot_setup_check - check boot time settings 500 * @dev: the netdevice 501 * 502 * Check boot time settings for the device. 503 * The found settings are set for the device to be used 504 * later in the device probing. 505 * Returns 0 if no settings found, 1 if they are. 506 */ 507 int netdev_boot_setup_check(struct net_device *dev) 508 { 509 struct netdev_boot_setup *s = dev_boot_setup; 510 int i; 511 512 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 513 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && 514 !strcmp(dev->name, s[i].name)) { 515 dev->irq = s[i].map.irq; 516 dev->base_addr = s[i].map.base_addr; 517 dev->mem_start = s[i].map.mem_start; 518 dev->mem_end = s[i].map.mem_end; 519 return 1; 520 } 521 } 522 return 0; 523 } 524 EXPORT_SYMBOL(netdev_boot_setup_check); 525 526 527 /** 528 * netdev_boot_base - get address from boot time settings 529 * @prefix: prefix for network device 530 * @unit: id for network device 531 * 532 * Check boot time settings for the base address of device. 533 * The found settings are set for the device to be used 534 * later in the device probing. 535 * Returns 0 if no settings found. 536 */ 537 unsigned long netdev_boot_base(const char *prefix, int unit) 538 { 539 const struct netdev_boot_setup *s = dev_boot_setup; 540 char name[IFNAMSIZ]; 541 int i; 542 543 sprintf(name, "%s%d", prefix, unit); 544 545 /* 546 * If device already registered then return base of 1 547 * to indicate not to probe for this interface 548 */ 549 if (__dev_get_by_name(&init_net, name)) 550 return 1; 551 552 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) 553 if (!strcmp(name, s[i].name)) 554 return s[i].map.base_addr; 555 return 0; 556 } 557 558 /* 559 * Saves at boot time configured settings for any netdevice. 560 */ 561 int __init netdev_boot_setup(char *str) 562 { 563 int ints[5]; 564 struct ifmap map; 565 566 str = get_options(str, ARRAY_SIZE(ints), ints); 567 if (!str || !*str) 568 return 0; 569 570 /* Save settings */ 571 memset(&map, 0, sizeof(map)); 572 if (ints[0] > 0) 573 map.irq = ints[1]; 574 if (ints[0] > 1) 575 map.base_addr = ints[2]; 576 if (ints[0] > 2) 577 map.mem_start = ints[3]; 578 if (ints[0] > 3) 579 map.mem_end = ints[4]; 580 581 /* Add new entry to the list */ 582 return netdev_boot_setup_add(str, &map); 583 } 584 585 __setup("netdev=", netdev_boot_setup); 586 587 /******************************************************************************* 588 589 Device Interface Subroutines 590 591 *******************************************************************************/ 592 593 /** 594 * __dev_get_by_name - find a device by its name 595 * @net: the applicable net namespace 596 * @name: name to find 597 * 598 * Find an interface by name. Must be called under RTNL semaphore 599 * or @dev_base_lock. If the name is found a pointer to the device 600 * is returned. If the name is not found then %NULL is returned. The 601 * reference counters are not incremented so the caller must be 602 * careful with locks. 603 */ 604 605 struct net_device *__dev_get_by_name(struct net *net, const char *name) 606 { 607 struct hlist_node *p; 608 struct net_device *dev; 609 struct hlist_head *head = dev_name_hash(net, name); 610 611 hlist_for_each_entry(dev, p, head, name_hlist) 612 if (!strncmp(dev->name, name, IFNAMSIZ)) 613 return dev; 614 615 return NULL; 616 } 617 EXPORT_SYMBOL(__dev_get_by_name); 618 619 /** 620 * dev_get_by_name_rcu - find a device by its name 621 * @net: the applicable net namespace 622 * @name: name to find 623 * 624 * Find an interface by name. 625 * If the name is found a pointer to the device is returned. 626 * If the name is not found then %NULL is returned. 627 * The reference counters are not incremented so the caller must be 628 * careful with locks. The caller must hold RCU lock. 629 */ 630 631 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 632 { 633 struct hlist_node *p; 634 struct net_device *dev; 635 struct hlist_head *head = dev_name_hash(net, name); 636 637 hlist_for_each_entry_rcu(dev, p, head, name_hlist) 638 if (!strncmp(dev->name, name, IFNAMSIZ)) 639 return dev; 640 641 return NULL; 642 } 643 EXPORT_SYMBOL(dev_get_by_name_rcu); 644 645 /** 646 * dev_get_by_name - find a device by its name 647 * @net: the applicable net namespace 648 * @name: name to find 649 * 650 * Find an interface by name. This can be called from any 651 * context and does its own locking. The returned handle has 652 * the usage count incremented and the caller must use dev_put() to 653 * release it when it is no longer needed. %NULL is returned if no 654 * matching device is found. 655 */ 656 657 struct net_device *dev_get_by_name(struct net *net, const char *name) 658 { 659 struct net_device *dev; 660 661 rcu_read_lock(); 662 dev = dev_get_by_name_rcu(net, name); 663 if (dev) 664 dev_hold(dev); 665 rcu_read_unlock(); 666 return dev; 667 } 668 EXPORT_SYMBOL(dev_get_by_name); 669 670 /** 671 * __dev_get_by_index - find a device by its ifindex 672 * @net: the applicable net namespace 673 * @ifindex: index of device 674 * 675 * Search for an interface by index. Returns %NULL if the device 676 * is not found or a pointer to the device. The device has not 677 * had its reference counter increased so the caller must be careful 678 * about locking. The caller must hold either the RTNL semaphore 679 * or @dev_base_lock. 680 */ 681 682 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 683 { 684 struct hlist_node *p; 685 struct net_device *dev; 686 struct hlist_head *head = dev_index_hash(net, ifindex); 687 688 hlist_for_each_entry(dev, p, head, index_hlist) 689 if (dev->ifindex == ifindex) 690 return dev; 691 692 return NULL; 693 } 694 EXPORT_SYMBOL(__dev_get_by_index); 695 696 /** 697 * dev_get_by_index_rcu - find a device by its ifindex 698 * @net: the applicable net namespace 699 * @ifindex: index of device 700 * 701 * Search for an interface by index. Returns %NULL if the device 702 * is not found or a pointer to the device. The device has not 703 * had its reference counter increased so the caller must be careful 704 * about locking. The caller must hold RCU lock. 705 */ 706 707 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 708 { 709 struct hlist_node *p; 710 struct net_device *dev; 711 struct hlist_head *head = dev_index_hash(net, ifindex); 712 713 hlist_for_each_entry_rcu(dev, p, head, index_hlist) 714 if (dev->ifindex == ifindex) 715 return dev; 716 717 return NULL; 718 } 719 EXPORT_SYMBOL(dev_get_by_index_rcu); 720 721 722 /** 723 * dev_get_by_index - find a device by its ifindex 724 * @net: the applicable net namespace 725 * @ifindex: index of device 726 * 727 * Search for an interface by index. Returns NULL if the device 728 * is not found or a pointer to the device. The device returned has 729 * had a reference added and the pointer is safe until the user calls 730 * dev_put to indicate they have finished with it. 731 */ 732 733 struct net_device *dev_get_by_index(struct net *net, int ifindex) 734 { 735 struct net_device *dev; 736 737 rcu_read_lock(); 738 dev = dev_get_by_index_rcu(net, ifindex); 739 if (dev) 740 dev_hold(dev); 741 rcu_read_unlock(); 742 return dev; 743 } 744 EXPORT_SYMBOL(dev_get_by_index); 745 746 /** 747 * dev_getbyhwaddr_rcu - find a device by its hardware address 748 * @net: the applicable net namespace 749 * @type: media type of device 750 * @ha: hardware address 751 * 752 * Search for an interface by MAC address. Returns NULL if the device 753 * is not found or a pointer to the device. 754 * The caller must hold RCU or RTNL. 755 * The returned device has not had its ref count increased 756 * and the caller must therefore be careful about locking 757 * 758 */ 759 760 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 761 const char *ha) 762 { 763 struct net_device *dev; 764 765 for_each_netdev_rcu(net, dev) 766 if (dev->type == type && 767 !memcmp(dev->dev_addr, ha, dev->addr_len)) 768 return dev; 769 770 return NULL; 771 } 772 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 773 774 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type) 775 { 776 struct net_device *dev; 777 778 ASSERT_RTNL(); 779 for_each_netdev(net, dev) 780 if (dev->type == type) 781 return dev; 782 783 return NULL; 784 } 785 EXPORT_SYMBOL(__dev_getfirstbyhwtype); 786 787 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 788 { 789 struct net_device *dev, *ret = NULL; 790 791 rcu_read_lock(); 792 for_each_netdev_rcu(net, dev) 793 if (dev->type == type) { 794 dev_hold(dev); 795 ret = dev; 796 break; 797 } 798 rcu_read_unlock(); 799 return ret; 800 } 801 EXPORT_SYMBOL(dev_getfirstbyhwtype); 802 803 /** 804 * dev_get_by_flags_rcu - find any device with given flags 805 * @net: the applicable net namespace 806 * @if_flags: IFF_* values 807 * @mask: bitmask of bits in if_flags to check 808 * 809 * Search for any interface with the given flags. Returns NULL if a device 810 * is not found or a pointer to the device. Must be called inside 811 * rcu_read_lock(), and result refcount is unchanged. 812 */ 813 814 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags, 815 unsigned short mask) 816 { 817 struct net_device *dev, *ret; 818 819 ret = NULL; 820 for_each_netdev_rcu(net, dev) { 821 if (((dev->flags ^ if_flags) & mask) == 0) { 822 ret = dev; 823 break; 824 } 825 } 826 return ret; 827 } 828 EXPORT_SYMBOL(dev_get_by_flags_rcu); 829 830 /** 831 * dev_valid_name - check if name is okay for network device 832 * @name: name string 833 * 834 * Network device names need to be valid file names to 835 * to allow sysfs to work. We also disallow any kind of 836 * whitespace. 837 */ 838 int dev_valid_name(const char *name) 839 { 840 if (*name == '\0') 841 return 0; 842 if (strlen(name) >= IFNAMSIZ) 843 return 0; 844 if (!strcmp(name, ".") || !strcmp(name, "..")) 845 return 0; 846 847 while (*name) { 848 if (*name == '/' || isspace(*name)) 849 return 0; 850 name++; 851 } 852 return 1; 853 } 854 EXPORT_SYMBOL(dev_valid_name); 855 856 /** 857 * __dev_alloc_name - allocate a name for a device 858 * @net: network namespace to allocate the device name in 859 * @name: name format string 860 * @buf: scratch buffer and result name string 861 * 862 * Passed a format string - eg "lt%d" it will try and find a suitable 863 * id. It scans list of devices to build up a free map, then chooses 864 * the first empty slot. The caller must hold the dev_base or rtnl lock 865 * while allocating the name and adding the device in order to avoid 866 * duplicates. 867 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 868 * Returns the number of the unit assigned or a negative errno code. 869 */ 870 871 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 872 { 873 int i = 0; 874 const char *p; 875 const int max_netdevices = 8*PAGE_SIZE; 876 unsigned long *inuse; 877 struct net_device *d; 878 879 p = strnchr(name, IFNAMSIZ-1, '%'); 880 if (p) { 881 /* 882 * Verify the string as this thing may have come from 883 * the user. There must be either one "%d" and no other "%" 884 * characters. 885 */ 886 if (p[1] != 'd' || strchr(p + 2, '%')) 887 return -EINVAL; 888 889 /* Use one page as a bit array of possible slots */ 890 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 891 if (!inuse) 892 return -ENOMEM; 893 894 for_each_netdev(net, d) { 895 if (!sscanf(d->name, name, &i)) 896 continue; 897 if (i < 0 || i >= max_netdevices) 898 continue; 899 900 /* avoid cases where sscanf is not exact inverse of printf */ 901 snprintf(buf, IFNAMSIZ, name, i); 902 if (!strncmp(buf, d->name, IFNAMSIZ)) 903 set_bit(i, inuse); 904 } 905 906 i = find_first_zero_bit(inuse, max_netdevices); 907 free_page((unsigned long) inuse); 908 } 909 910 if (buf != name) 911 snprintf(buf, IFNAMSIZ, name, i); 912 if (!__dev_get_by_name(net, buf)) 913 return i; 914 915 /* It is possible to run out of possible slots 916 * when the name is long and there isn't enough space left 917 * for the digits, or if all bits are used. 918 */ 919 return -ENFILE; 920 } 921 922 /** 923 * dev_alloc_name - allocate a name for a device 924 * @dev: device 925 * @name: name format string 926 * 927 * Passed a format string - eg "lt%d" it will try and find a suitable 928 * id. It scans list of devices to build up a free map, then chooses 929 * the first empty slot. The caller must hold the dev_base or rtnl lock 930 * while allocating the name and adding the device in order to avoid 931 * duplicates. 932 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 933 * Returns the number of the unit assigned or a negative errno code. 934 */ 935 936 int dev_alloc_name(struct net_device *dev, const char *name) 937 { 938 char buf[IFNAMSIZ]; 939 struct net *net; 940 int ret; 941 942 BUG_ON(!dev_net(dev)); 943 net = dev_net(dev); 944 ret = __dev_alloc_name(net, name, buf); 945 if (ret >= 0) 946 strlcpy(dev->name, buf, IFNAMSIZ); 947 return ret; 948 } 949 EXPORT_SYMBOL(dev_alloc_name); 950 951 static int dev_get_valid_name(struct net_device *dev, const char *name) 952 { 953 struct net *net; 954 955 BUG_ON(!dev_net(dev)); 956 net = dev_net(dev); 957 958 if (!dev_valid_name(name)) 959 return -EINVAL; 960 961 if (strchr(name, '%')) 962 return dev_alloc_name(dev, name); 963 else if (__dev_get_by_name(net, name)) 964 return -EEXIST; 965 else if (dev->name != name) 966 strlcpy(dev->name, name, IFNAMSIZ); 967 968 return 0; 969 } 970 971 /** 972 * dev_change_name - change name of a device 973 * @dev: device 974 * @newname: name (or format string) must be at least IFNAMSIZ 975 * 976 * Change name of a device, can pass format strings "eth%d". 977 * for wildcarding. 978 */ 979 int dev_change_name(struct net_device *dev, const char *newname) 980 { 981 char oldname[IFNAMSIZ]; 982 int err = 0; 983 int ret; 984 struct net *net; 985 986 ASSERT_RTNL(); 987 BUG_ON(!dev_net(dev)); 988 989 net = dev_net(dev); 990 if (dev->flags & IFF_UP) 991 return -EBUSY; 992 993 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) 994 return 0; 995 996 memcpy(oldname, dev->name, IFNAMSIZ); 997 998 err = dev_get_valid_name(dev, newname); 999 if (err < 0) 1000 return err; 1001 1002 rollback: 1003 ret = device_rename(&dev->dev, dev->name); 1004 if (ret) { 1005 memcpy(dev->name, oldname, IFNAMSIZ); 1006 return ret; 1007 } 1008 1009 write_lock_bh(&dev_base_lock); 1010 hlist_del_rcu(&dev->name_hlist); 1011 write_unlock_bh(&dev_base_lock); 1012 1013 synchronize_rcu(); 1014 1015 write_lock_bh(&dev_base_lock); 1016 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 1017 write_unlock_bh(&dev_base_lock); 1018 1019 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1020 ret = notifier_to_errno(ret); 1021 1022 if (ret) { 1023 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1024 if (err >= 0) { 1025 err = ret; 1026 memcpy(dev->name, oldname, IFNAMSIZ); 1027 goto rollback; 1028 } else { 1029 printk(KERN_ERR 1030 "%s: name change rollback failed: %d.\n", 1031 dev->name, ret); 1032 } 1033 } 1034 1035 return err; 1036 } 1037 1038 /** 1039 * dev_set_alias - change ifalias of a device 1040 * @dev: device 1041 * @alias: name up to IFALIASZ 1042 * @len: limit of bytes to copy from info 1043 * 1044 * Set ifalias for a device, 1045 */ 1046 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1047 { 1048 ASSERT_RTNL(); 1049 1050 if (len >= IFALIASZ) 1051 return -EINVAL; 1052 1053 if (!len) { 1054 if (dev->ifalias) { 1055 kfree(dev->ifalias); 1056 dev->ifalias = NULL; 1057 } 1058 return 0; 1059 } 1060 1061 dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL); 1062 if (!dev->ifalias) 1063 return -ENOMEM; 1064 1065 strlcpy(dev->ifalias, alias, len+1); 1066 return len; 1067 } 1068 1069 1070 /** 1071 * netdev_features_change - device changes features 1072 * @dev: device to cause notification 1073 * 1074 * Called to indicate a device has changed features. 1075 */ 1076 void netdev_features_change(struct net_device *dev) 1077 { 1078 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1079 } 1080 EXPORT_SYMBOL(netdev_features_change); 1081 1082 /** 1083 * netdev_state_change - device changes state 1084 * @dev: device to cause notification 1085 * 1086 * Called to indicate a device has changed state. This function calls 1087 * the notifier chains for netdev_chain and sends a NEWLINK message 1088 * to the routing socket. 1089 */ 1090 void netdev_state_change(struct net_device *dev) 1091 { 1092 if (dev->flags & IFF_UP) { 1093 call_netdevice_notifiers(NETDEV_CHANGE, dev); 1094 rtmsg_ifinfo(RTM_NEWLINK, dev, 0); 1095 } 1096 } 1097 EXPORT_SYMBOL(netdev_state_change); 1098 1099 int netdev_bonding_change(struct net_device *dev, unsigned long event) 1100 { 1101 return call_netdevice_notifiers(event, dev); 1102 } 1103 EXPORT_SYMBOL(netdev_bonding_change); 1104 1105 /** 1106 * dev_load - load a network module 1107 * @net: the applicable net namespace 1108 * @name: name of interface 1109 * 1110 * If a network interface is not present and the process has suitable 1111 * privileges this function loads the module. If module loading is not 1112 * available in this kernel then it becomes a nop. 1113 */ 1114 1115 void dev_load(struct net *net, const char *name) 1116 { 1117 struct net_device *dev; 1118 int no_module; 1119 1120 rcu_read_lock(); 1121 dev = dev_get_by_name_rcu(net, name); 1122 rcu_read_unlock(); 1123 1124 no_module = !dev; 1125 if (no_module && capable(CAP_NET_ADMIN)) 1126 no_module = request_module("netdev-%s", name); 1127 if (no_module && capable(CAP_SYS_MODULE)) { 1128 if (!request_module("%s", name)) 1129 pr_err("Loading kernel module for a network device " 1130 "with CAP_SYS_MODULE (deprecated). Use CAP_NET_ADMIN and alias netdev-%s " 1131 "instead\n", name); 1132 } 1133 } 1134 EXPORT_SYMBOL(dev_load); 1135 1136 static int __dev_open(struct net_device *dev) 1137 { 1138 const struct net_device_ops *ops = dev->netdev_ops; 1139 int ret; 1140 1141 ASSERT_RTNL(); 1142 1143 if (!netif_device_present(dev)) 1144 return -ENODEV; 1145 1146 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev); 1147 ret = notifier_to_errno(ret); 1148 if (ret) 1149 return ret; 1150 1151 set_bit(__LINK_STATE_START, &dev->state); 1152 1153 if (ops->ndo_validate_addr) 1154 ret = ops->ndo_validate_addr(dev); 1155 1156 if (!ret && ops->ndo_open) 1157 ret = ops->ndo_open(dev); 1158 1159 if (ret) 1160 clear_bit(__LINK_STATE_START, &dev->state); 1161 else { 1162 dev->flags |= IFF_UP; 1163 net_dmaengine_get(); 1164 dev_set_rx_mode(dev); 1165 dev_activate(dev); 1166 } 1167 1168 return ret; 1169 } 1170 1171 /** 1172 * dev_open - prepare an interface for use. 1173 * @dev: device to open 1174 * 1175 * Takes a device from down to up state. The device's private open 1176 * function is invoked and then the multicast lists are loaded. Finally 1177 * the device is moved into the up state and a %NETDEV_UP message is 1178 * sent to the netdev notifier chain. 1179 * 1180 * Calling this function on an active interface is a nop. On a failure 1181 * a negative errno code is returned. 1182 */ 1183 int dev_open(struct net_device *dev) 1184 { 1185 int ret; 1186 1187 if (dev->flags & IFF_UP) 1188 return 0; 1189 1190 ret = __dev_open(dev); 1191 if (ret < 0) 1192 return ret; 1193 1194 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1195 call_netdevice_notifiers(NETDEV_UP, dev); 1196 1197 return ret; 1198 } 1199 EXPORT_SYMBOL(dev_open); 1200 1201 static int __dev_close_many(struct list_head *head) 1202 { 1203 struct net_device *dev; 1204 1205 ASSERT_RTNL(); 1206 might_sleep(); 1207 1208 list_for_each_entry(dev, head, unreg_list) { 1209 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1210 1211 clear_bit(__LINK_STATE_START, &dev->state); 1212 1213 /* Synchronize to scheduled poll. We cannot touch poll list, it 1214 * can be even on different cpu. So just clear netif_running(). 1215 * 1216 * dev->stop() will invoke napi_disable() on all of it's 1217 * napi_struct instances on this device. 1218 */ 1219 smp_mb__after_clear_bit(); /* Commit netif_running(). */ 1220 } 1221 1222 dev_deactivate_many(head); 1223 1224 list_for_each_entry(dev, head, unreg_list) { 1225 const struct net_device_ops *ops = dev->netdev_ops; 1226 1227 /* 1228 * Call the device specific close. This cannot fail. 1229 * Only if device is UP 1230 * 1231 * We allow it to be called even after a DETACH hot-plug 1232 * event. 1233 */ 1234 if (ops->ndo_stop) 1235 ops->ndo_stop(dev); 1236 1237 dev->flags &= ~IFF_UP; 1238 net_dmaengine_put(); 1239 } 1240 1241 return 0; 1242 } 1243 1244 static int __dev_close(struct net_device *dev) 1245 { 1246 int retval; 1247 LIST_HEAD(single); 1248 1249 list_add(&dev->unreg_list, &single); 1250 retval = __dev_close_many(&single); 1251 list_del(&single); 1252 return retval; 1253 } 1254 1255 static int dev_close_many(struct list_head *head) 1256 { 1257 struct net_device *dev, *tmp; 1258 LIST_HEAD(tmp_list); 1259 1260 list_for_each_entry_safe(dev, tmp, head, unreg_list) 1261 if (!(dev->flags & IFF_UP)) 1262 list_move(&dev->unreg_list, &tmp_list); 1263 1264 __dev_close_many(head); 1265 1266 list_for_each_entry(dev, head, unreg_list) { 1267 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1268 call_netdevice_notifiers(NETDEV_DOWN, dev); 1269 } 1270 1271 /* rollback_registered_many needs the complete original list */ 1272 list_splice(&tmp_list, head); 1273 return 0; 1274 } 1275 1276 /** 1277 * dev_close - shutdown an interface. 1278 * @dev: device to shutdown 1279 * 1280 * This function moves an active device into down state. A 1281 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1282 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1283 * chain. 1284 */ 1285 int dev_close(struct net_device *dev) 1286 { 1287 if (dev->flags & IFF_UP) { 1288 LIST_HEAD(single); 1289 1290 list_add(&dev->unreg_list, &single); 1291 dev_close_many(&single); 1292 list_del(&single); 1293 } 1294 return 0; 1295 } 1296 EXPORT_SYMBOL(dev_close); 1297 1298 1299 /** 1300 * dev_disable_lro - disable Large Receive Offload on a device 1301 * @dev: device 1302 * 1303 * Disable Large Receive Offload (LRO) on a net device. Must be 1304 * called under RTNL. This is needed if received packets may be 1305 * forwarded to another interface. 1306 */ 1307 void dev_disable_lro(struct net_device *dev) 1308 { 1309 u32 flags; 1310 1311 if (dev->ethtool_ops && dev->ethtool_ops->get_flags) 1312 flags = dev->ethtool_ops->get_flags(dev); 1313 else 1314 flags = ethtool_op_get_flags(dev); 1315 1316 if (!(flags & ETH_FLAG_LRO)) 1317 return; 1318 1319 __ethtool_set_flags(dev, flags & ~ETH_FLAG_LRO); 1320 if (unlikely(dev->features & NETIF_F_LRO)) 1321 netdev_WARN(dev, "failed to disable LRO!\n"); 1322 } 1323 EXPORT_SYMBOL(dev_disable_lro); 1324 1325 1326 static int dev_boot_phase = 1; 1327 1328 /** 1329 * register_netdevice_notifier - register a network notifier block 1330 * @nb: notifier 1331 * 1332 * Register a notifier to be called when network device events occur. 1333 * The notifier passed is linked into the kernel structures and must 1334 * not be reused until it has been unregistered. A negative errno code 1335 * is returned on a failure. 1336 * 1337 * When registered all registration and up events are replayed 1338 * to the new notifier to allow device to have a race free 1339 * view of the network device list. 1340 */ 1341 1342 int register_netdevice_notifier(struct notifier_block *nb) 1343 { 1344 struct net_device *dev; 1345 struct net_device *last; 1346 struct net *net; 1347 int err; 1348 1349 rtnl_lock(); 1350 err = raw_notifier_chain_register(&netdev_chain, nb); 1351 if (err) 1352 goto unlock; 1353 if (dev_boot_phase) 1354 goto unlock; 1355 for_each_net(net) { 1356 for_each_netdev(net, dev) { 1357 err = nb->notifier_call(nb, NETDEV_REGISTER, dev); 1358 err = notifier_to_errno(err); 1359 if (err) 1360 goto rollback; 1361 1362 if (!(dev->flags & IFF_UP)) 1363 continue; 1364 1365 nb->notifier_call(nb, NETDEV_UP, dev); 1366 } 1367 } 1368 1369 unlock: 1370 rtnl_unlock(); 1371 return err; 1372 1373 rollback: 1374 last = dev; 1375 for_each_net(net) { 1376 for_each_netdev(net, dev) { 1377 if (dev == last) 1378 break; 1379 1380 if (dev->flags & IFF_UP) { 1381 nb->notifier_call(nb, NETDEV_GOING_DOWN, dev); 1382 nb->notifier_call(nb, NETDEV_DOWN, dev); 1383 } 1384 nb->notifier_call(nb, NETDEV_UNREGISTER, dev); 1385 nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev); 1386 } 1387 } 1388 1389 raw_notifier_chain_unregister(&netdev_chain, nb); 1390 goto unlock; 1391 } 1392 EXPORT_SYMBOL(register_netdevice_notifier); 1393 1394 /** 1395 * unregister_netdevice_notifier - unregister a network notifier block 1396 * @nb: notifier 1397 * 1398 * Unregister a notifier previously registered by 1399 * register_netdevice_notifier(). The notifier is unlinked into the 1400 * kernel structures and may then be reused. A negative errno code 1401 * is returned on a failure. 1402 */ 1403 1404 int unregister_netdevice_notifier(struct notifier_block *nb) 1405 { 1406 int err; 1407 1408 rtnl_lock(); 1409 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1410 rtnl_unlock(); 1411 return err; 1412 } 1413 EXPORT_SYMBOL(unregister_netdevice_notifier); 1414 1415 /** 1416 * call_netdevice_notifiers - call all network notifier blocks 1417 * @val: value passed unmodified to notifier function 1418 * @dev: net_device pointer passed unmodified to notifier function 1419 * 1420 * Call all network notifier blocks. Parameters and return value 1421 * are as for raw_notifier_call_chain(). 1422 */ 1423 1424 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1425 { 1426 ASSERT_RTNL(); 1427 return raw_notifier_call_chain(&netdev_chain, val, dev); 1428 } 1429 EXPORT_SYMBOL(call_netdevice_notifiers); 1430 1431 /* When > 0 there are consumers of rx skb time stamps */ 1432 static atomic_t netstamp_needed = ATOMIC_INIT(0); 1433 1434 void net_enable_timestamp(void) 1435 { 1436 atomic_inc(&netstamp_needed); 1437 } 1438 EXPORT_SYMBOL(net_enable_timestamp); 1439 1440 void net_disable_timestamp(void) 1441 { 1442 atomic_dec(&netstamp_needed); 1443 } 1444 EXPORT_SYMBOL(net_disable_timestamp); 1445 1446 static inline void net_timestamp_set(struct sk_buff *skb) 1447 { 1448 if (atomic_read(&netstamp_needed)) 1449 __net_timestamp(skb); 1450 else 1451 skb->tstamp.tv64 = 0; 1452 } 1453 1454 static inline void net_timestamp_check(struct sk_buff *skb) 1455 { 1456 if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed)) 1457 __net_timestamp(skb); 1458 } 1459 1460 static inline bool is_skb_forwardable(struct net_device *dev, 1461 struct sk_buff *skb) 1462 { 1463 unsigned int len; 1464 1465 if (!(dev->flags & IFF_UP)) 1466 return false; 1467 1468 len = dev->mtu + dev->hard_header_len + VLAN_HLEN; 1469 if (skb->len <= len) 1470 return true; 1471 1472 /* if TSO is enabled, we don't care about the length as the packet 1473 * could be forwarded without being segmented before 1474 */ 1475 if (skb_is_gso(skb)) 1476 return true; 1477 1478 return false; 1479 } 1480 1481 /** 1482 * dev_forward_skb - loopback an skb to another netif 1483 * 1484 * @dev: destination network device 1485 * @skb: buffer to forward 1486 * 1487 * return values: 1488 * NET_RX_SUCCESS (no congestion) 1489 * NET_RX_DROP (packet was dropped, but freed) 1490 * 1491 * dev_forward_skb can be used for injecting an skb from the 1492 * start_xmit function of one device into the receive queue 1493 * of another device. 1494 * 1495 * The receiving device may be in another namespace, so 1496 * we have to clear all information in the skb that could 1497 * impact namespace isolation. 1498 */ 1499 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 1500 { 1501 skb_orphan(skb); 1502 nf_reset(skb); 1503 1504 if (unlikely(!is_skb_forwardable(dev, skb))) { 1505 atomic_long_inc(&dev->rx_dropped); 1506 kfree_skb(skb); 1507 return NET_RX_DROP; 1508 } 1509 skb_set_dev(skb, dev); 1510 skb->tstamp.tv64 = 0; 1511 skb->pkt_type = PACKET_HOST; 1512 skb->protocol = eth_type_trans(skb, dev); 1513 return netif_rx(skb); 1514 } 1515 EXPORT_SYMBOL_GPL(dev_forward_skb); 1516 1517 static inline int deliver_skb(struct sk_buff *skb, 1518 struct packet_type *pt_prev, 1519 struct net_device *orig_dev) 1520 { 1521 atomic_inc(&skb->users); 1522 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1523 } 1524 1525 /* 1526 * Support routine. Sends outgoing frames to any network 1527 * taps currently in use. 1528 */ 1529 1530 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 1531 { 1532 struct packet_type *ptype; 1533 struct sk_buff *skb2 = NULL; 1534 struct packet_type *pt_prev = NULL; 1535 1536 rcu_read_lock(); 1537 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1538 /* Never send packets back to the socket 1539 * they originated from - MvS ([email protected]) 1540 */ 1541 if ((ptype->dev == dev || !ptype->dev) && 1542 (ptype->af_packet_priv == NULL || 1543 (struct sock *)ptype->af_packet_priv != skb->sk)) { 1544 if (pt_prev) { 1545 deliver_skb(skb2, pt_prev, skb->dev); 1546 pt_prev = ptype; 1547 continue; 1548 } 1549 1550 skb2 = skb_clone(skb, GFP_ATOMIC); 1551 if (!skb2) 1552 break; 1553 1554 net_timestamp_set(skb2); 1555 1556 /* skb->nh should be correctly 1557 set by sender, so that the second statement is 1558 just protection against buggy protocols. 1559 */ 1560 skb_reset_mac_header(skb2); 1561 1562 if (skb_network_header(skb2) < skb2->data || 1563 skb2->network_header > skb2->tail) { 1564 if (net_ratelimit()) 1565 printk(KERN_CRIT "protocol %04x is " 1566 "buggy, dev %s\n", 1567 ntohs(skb2->protocol), 1568 dev->name); 1569 skb_reset_network_header(skb2); 1570 } 1571 1572 skb2->transport_header = skb2->network_header; 1573 skb2->pkt_type = PACKET_OUTGOING; 1574 pt_prev = ptype; 1575 } 1576 } 1577 if (pt_prev) 1578 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 1579 rcu_read_unlock(); 1580 } 1581 1582 /* netif_setup_tc - Handle tc mappings on real_num_tx_queues change 1583 * @dev: Network device 1584 * @txq: number of queues available 1585 * 1586 * If real_num_tx_queues is changed the tc mappings may no longer be 1587 * valid. To resolve this verify the tc mapping remains valid and if 1588 * not NULL the mapping. With no priorities mapping to this 1589 * offset/count pair it will no longer be used. In the worst case TC0 1590 * is invalid nothing can be done so disable priority mappings. If is 1591 * expected that drivers will fix this mapping if they can before 1592 * calling netif_set_real_num_tx_queues. 1593 */ 1594 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 1595 { 1596 int i; 1597 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 1598 1599 /* If TC0 is invalidated disable TC mapping */ 1600 if (tc->offset + tc->count > txq) { 1601 pr_warning("Number of in use tx queues changed " 1602 "invalidating tc mappings. Priority " 1603 "traffic classification disabled!\n"); 1604 dev->num_tc = 0; 1605 return; 1606 } 1607 1608 /* Invalidated prio to tc mappings set to TC0 */ 1609 for (i = 1; i < TC_BITMASK + 1; i++) { 1610 int q = netdev_get_prio_tc_map(dev, i); 1611 1612 tc = &dev->tc_to_txq[q]; 1613 if (tc->offset + tc->count > txq) { 1614 pr_warning("Number of in use tx queues " 1615 "changed. Priority %i to tc " 1616 "mapping %i is no longer valid " 1617 "setting map to 0\n", 1618 i, q); 1619 netdev_set_prio_tc_map(dev, i, 0); 1620 } 1621 } 1622 } 1623 1624 /* 1625 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 1626 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed. 1627 */ 1628 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 1629 { 1630 int rc; 1631 1632 if (txq < 1 || txq > dev->num_tx_queues) 1633 return -EINVAL; 1634 1635 if (dev->reg_state == NETREG_REGISTERED || 1636 dev->reg_state == NETREG_UNREGISTERING) { 1637 ASSERT_RTNL(); 1638 1639 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 1640 txq); 1641 if (rc) 1642 return rc; 1643 1644 if (dev->num_tc) 1645 netif_setup_tc(dev, txq); 1646 1647 if (txq < dev->real_num_tx_queues) 1648 qdisc_reset_all_tx_gt(dev, txq); 1649 } 1650 1651 dev->real_num_tx_queues = txq; 1652 return 0; 1653 } 1654 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 1655 1656 #ifdef CONFIG_RPS 1657 /** 1658 * netif_set_real_num_rx_queues - set actual number of RX queues used 1659 * @dev: Network device 1660 * @rxq: Actual number of RX queues 1661 * 1662 * This must be called either with the rtnl_lock held or before 1663 * registration of the net device. Returns 0 on success, or a 1664 * negative error code. If called before registration, it always 1665 * succeeds. 1666 */ 1667 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 1668 { 1669 int rc; 1670 1671 if (rxq < 1 || rxq > dev->num_rx_queues) 1672 return -EINVAL; 1673 1674 if (dev->reg_state == NETREG_REGISTERED) { 1675 ASSERT_RTNL(); 1676 1677 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 1678 rxq); 1679 if (rc) 1680 return rc; 1681 } 1682 1683 dev->real_num_rx_queues = rxq; 1684 return 0; 1685 } 1686 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 1687 #endif 1688 1689 static inline void __netif_reschedule(struct Qdisc *q) 1690 { 1691 struct softnet_data *sd; 1692 unsigned long flags; 1693 1694 local_irq_save(flags); 1695 sd = &__get_cpu_var(softnet_data); 1696 q->next_sched = NULL; 1697 *sd->output_queue_tailp = q; 1698 sd->output_queue_tailp = &q->next_sched; 1699 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1700 local_irq_restore(flags); 1701 } 1702 1703 void __netif_schedule(struct Qdisc *q) 1704 { 1705 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 1706 __netif_reschedule(q); 1707 } 1708 EXPORT_SYMBOL(__netif_schedule); 1709 1710 void dev_kfree_skb_irq(struct sk_buff *skb) 1711 { 1712 if (atomic_dec_and_test(&skb->users)) { 1713 struct softnet_data *sd; 1714 unsigned long flags; 1715 1716 local_irq_save(flags); 1717 sd = &__get_cpu_var(softnet_data); 1718 skb->next = sd->completion_queue; 1719 sd->completion_queue = skb; 1720 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1721 local_irq_restore(flags); 1722 } 1723 } 1724 EXPORT_SYMBOL(dev_kfree_skb_irq); 1725 1726 void dev_kfree_skb_any(struct sk_buff *skb) 1727 { 1728 if (in_irq() || irqs_disabled()) 1729 dev_kfree_skb_irq(skb); 1730 else 1731 dev_kfree_skb(skb); 1732 } 1733 EXPORT_SYMBOL(dev_kfree_skb_any); 1734 1735 1736 /** 1737 * netif_device_detach - mark device as removed 1738 * @dev: network device 1739 * 1740 * Mark device as removed from system and therefore no longer available. 1741 */ 1742 void netif_device_detach(struct net_device *dev) 1743 { 1744 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 1745 netif_running(dev)) { 1746 netif_tx_stop_all_queues(dev); 1747 } 1748 } 1749 EXPORT_SYMBOL(netif_device_detach); 1750 1751 /** 1752 * netif_device_attach - mark device as attached 1753 * @dev: network device 1754 * 1755 * Mark device as attached from system and restart if needed. 1756 */ 1757 void netif_device_attach(struct net_device *dev) 1758 { 1759 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 1760 netif_running(dev)) { 1761 netif_tx_wake_all_queues(dev); 1762 __netdev_watchdog_up(dev); 1763 } 1764 } 1765 EXPORT_SYMBOL(netif_device_attach); 1766 1767 /** 1768 * skb_dev_set -- assign a new device to a buffer 1769 * @skb: buffer for the new device 1770 * @dev: network device 1771 * 1772 * If an skb is owned by a device already, we have to reset 1773 * all data private to the namespace a device belongs to 1774 * before assigning it a new device. 1775 */ 1776 #ifdef CONFIG_NET_NS 1777 void skb_set_dev(struct sk_buff *skb, struct net_device *dev) 1778 { 1779 skb_dst_drop(skb); 1780 if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) { 1781 secpath_reset(skb); 1782 nf_reset(skb); 1783 skb_init_secmark(skb); 1784 skb->mark = 0; 1785 skb->priority = 0; 1786 skb->nf_trace = 0; 1787 skb->ipvs_property = 0; 1788 #ifdef CONFIG_NET_SCHED 1789 skb->tc_index = 0; 1790 #endif 1791 } 1792 skb->dev = dev; 1793 } 1794 EXPORT_SYMBOL(skb_set_dev); 1795 #endif /* CONFIG_NET_NS */ 1796 1797 /* 1798 * Invalidate hardware checksum when packet is to be mangled, and 1799 * complete checksum manually on outgoing path. 1800 */ 1801 int skb_checksum_help(struct sk_buff *skb) 1802 { 1803 __wsum csum; 1804 int ret = 0, offset; 1805 1806 if (skb->ip_summed == CHECKSUM_COMPLETE) 1807 goto out_set_summed; 1808 1809 if (unlikely(skb_shinfo(skb)->gso_size)) { 1810 /* Let GSO fix up the checksum. */ 1811 goto out_set_summed; 1812 } 1813 1814 offset = skb_checksum_start_offset(skb); 1815 BUG_ON(offset >= skb_headlen(skb)); 1816 csum = skb_checksum(skb, offset, skb->len - offset, 0); 1817 1818 offset += skb->csum_offset; 1819 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); 1820 1821 if (skb_cloned(skb) && 1822 !skb_clone_writable(skb, offset + sizeof(__sum16))) { 1823 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 1824 if (ret) 1825 goto out; 1826 } 1827 1828 *(__sum16 *)(skb->data + offset) = csum_fold(csum); 1829 out_set_summed: 1830 skb->ip_summed = CHECKSUM_NONE; 1831 out: 1832 return ret; 1833 } 1834 EXPORT_SYMBOL(skb_checksum_help); 1835 1836 /** 1837 * skb_gso_segment - Perform segmentation on skb. 1838 * @skb: buffer to segment 1839 * @features: features for the output path (see dev->features) 1840 * 1841 * This function segments the given skb and returns a list of segments. 1842 * 1843 * It may return NULL if the skb requires no segmentation. This is 1844 * only possible when GSO is used for verifying header integrity. 1845 */ 1846 struct sk_buff *skb_gso_segment(struct sk_buff *skb, u32 features) 1847 { 1848 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); 1849 struct packet_type *ptype; 1850 __be16 type = skb->protocol; 1851 int vlan_depth = ETH_HLEN; 1852 int err; 1853 1854 while (type == htons(ETH_P_8021Q)) { 1855 struct vlan_hdr *vh; 1856 1857 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN))) 1858 return ERR_PTR(-EINVAL); 1859 1860 vh = (struct vlan_hdr *)(skb->data + vlan_depth); 1861 type = vh->h_vlan_encapsulated_proto; 1862 vlan_depth += VLAN_HLEN; 1863 } 1864 1865 skb_reset_mac_header(skb); 1866 skb->mac_len = skb->network_header - skb->mac_header; 1867 __skb_pull(skb, skb->mac_len); 1868 1869 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1870 struct net_device *dev = skb->dev; 1871 struct ethtool_drvinfo info = {}; 1872 1873 if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo) 1874 dev->ethtool_ops->get_drvinfo(dev, &info); 1875 1876 WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d ip_summed=%d\n", 1877 info.driver, dev ? dev->features : 0L, 1878 skb->sk ? skb->sk->sk_route_caps : 0L, 1879 skb->len, skb->data_len, skb->ip_summed); 1880 1881 if (skb_header_cloned(skb) && 1882 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) 1883 return ERR_PTR(err); 1884 } 1885 1886 rcu_read_lock(); 1887 list_for_each_entry_rcu(ptype, 1888 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 1889 if (ptype->type == type && !ptype->dev && ptype->gso_segment) { 1890 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1891 err = ptype->gso_send_check(skb); 1892 segs = ERR_PTR(err); 1893 if (err || skb_gso_ok(skb, features)) 1894 break; 1895 __skb_push(skb, (skb->data - 1896 skb_network_header(skb))); 1897 } 1898 segs = ptype->gso_segment(skb, features); 1899 break; 1900 } 1901 } 1902 rcu_read_unlock(); 1903 1904 __skb_push(skb, skb->data - skb_mac_header(skb)); 1905 1906 return segs; 1907 } 1908 EXPORT_SYMBOL(skb_gso_segment); 1909 1910 /* Take action when hardware reception checksum errors are detected. */ 1911 #ifdef CONFIG_BUG 1912 void netdev_rx_csum_fault(struct net_device *dev) 1913 { 1914 if (net_ratelimit()) { 1915 printk(KERN_ERR "%s: hw csum failure.\n", 1916 dev ? dev->name : "<unknown>"); 1917 dump_stack(); 1918 } 1919 } 1920 EXPORT_SYMBOL(netdev_rx_csum_fault); 1921 #endif 1922 1923 /* Actually, we should eliminate this check as soon as we know, that: 1924 * 1. IOMMU is present and allows to map all the memory. 1925 * 2. No high memory really exists on this machine. 1926 */ 1927 1928 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 1929 { 1930 #ifdef CONFIG_HIGHMEM 1931 int i; 1932 if (!(dev->features & NETIF_F_HIGHDMA)) { 1933 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 1934 if (PageHighMem(skb_shinfo(skb)->frags[i].page)) 1935 return 1; 1936 } 1937 1938 if (PCI_DMA_BUS_IS_PHYS) { 1939 struct device *pdev = dev->dev.parent; 1940 1941 if (!pdev) 1942 return 0; 1943 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 1944 dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page); 1945 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask) 1946 return 1; 1947 } 1948 } 1949 #endif 1950 return 0; 1951 } 1952 1953 struct dev_gso_cb { 1954 void (*destructor)(struct sk_buff *skb); 1955 }; 1956 1957 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) 1958 1959 static void dev_gso_skb_destructor(struct sk_buff *skb) 1960 { 1961 struct dev_gso_cb *cb; 1962 1963 do { 1964 struct sk_buff *nskb = skb->next; 1965 1966 skb->next = nskb->next; 1967 nskb->next = NULL; 1968 kfree_skb(nskb); 1969 } while (skb->next); 1970 1971 cb = DEV_GSO_CB(skb); 1972 if (cb->destructor) 1973 cb->destructor(skb); 1974 } 1975 1976 /** 1977 * dev_gso_segment - Perform emulated hardware segmentation on skb. 1978 * @skb: buffer to segment 1979 * @features: device features as applicable to this skb 1980 * 1981 * This function segments the given skb and stores the list of segments 1982 * in skb->next. 1983 */ 1984 static int dev_gso_segment(struct sk_buff *skb, int features) 1985 { 1986 struct sk_buff *segs; 1987 1988 segs = skb_gso_segment(skb, features); 1989 1990 /* Verifying header integrity only. */ 1991 if (!segs) 1992 return 0; 1993 1994 if (IS_ERR(segs)) 1995 return PTR_ERR(segs); 1996 1997 skb->next = segs; 1998 DEV_GSO_CB(skb)->destructor = skb->destructor; 1999 skb->destructor = dev_gso_skb_destructor; 2000 2001 return 0; 2002 } 2003 2004 /* 2005 * Try to orphan skb early, right before transmission by the device. 2006 * We cannot orphan skb if tx timestamp is requested or the sk-reference 2007 * is needed on driver level for other reasons, e.g. see net/can/raw.c 2008 */ 2009 static inline void skb_orphan_try(struct sk_buff *skb) 2010 { 2011 struct sock *sk = skb->sk; 2012 2013 if (sk && !skb_shinfo(skb)->tx_flags) { 2014 /* skb_tx_hash() wont be able to get sk. 2015 * We copy sk_hash into skb->rxhash 2016 */ 2017 if (!skb->rxhash) 2018 skb->rxhash = sk->sk_hash; 2019 skb_orphan(skb); 2020 } 2021 } 2022 2023 static bool can_checksum_protocol(unsigned long features, __be16 protocol) 2024 { 2025 return ((features & NETIF_F_GEN_CSUM) || 2026 ((features & NETIF_F_V4_CSUM) && 2027 protocol == htons(ETH_P_IP)) || 2028 ((features & NETIF_F_V6_CSUM) && 2029 protocol == htons(ETH_P_IPV6)) || 2030 ((features & NETIF_F_FCOE_CRC) && 2031 protocol == htons(ETH_P_FCOE))); 2032 } 2033 2034 static u32 harmonize_features(struct sk_buff *skb, __be16 protocol, u32 features) 2035 { 2036 if (!can_checksum_protocol(features, protocol)) { 2037 features &= ~NETIF_F_ALL_CSUM; 2038 features &= ~NETIF_F_SG; 2039 } else if (illegal_highdma(skb->dev, skb)) { 2040 features &= ~NETIF_F_SG; 2041 } 2042 2043 return features; 2044 } 2045 2046 u32 netif_skb_features(struct sk_buff *skb) 2047 { 2048 __be16 protocol = skb->protocol; 2049 u32 features = skb->dev->features; 2050 2051 if (protocol == htons(ETH_P_8021Q)) { 2052 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; 2053 protocol = veh->h_vlan_encapsulated_proto; 2054 } else if (!vlan_tx_tag_present(skb)) { 2055 return harmonize_features(skb, protocol, features); 2056 } 2057 2058 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_TX); 2059 2060 if (protocol != htons(ETH_P_8021Q)) { 2061 return harmonize_features(skb, protocol, features); 2062 } else { 2063 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | 2064 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX; 2065 return harmonize_features(skb, protocol, features); 2066 } 2067 } 2068 EXPORT_SYMBOL(netif_skb_features); 2069 2070 /* 2071 * Returns true if either: 2072 * 1. skb has frag_list and the device doesn't support FRAGLIST, or 2073 * 2. skb is fragmented and the device does not support SG, or if 2074 * at least one of fragments is in highmem and device does not 2075 * support DMA from it. 2076 */ 2077 static inline int skb_needs_linearize(struct sk_buff *skb, 2078 int features) 2079 { 2080 return skb_is_nonlinear(skb) && 2081 ((skb_has_frag_list(skb) && 2082 !(features & NETIF_F_FRAGLIST)) || 2083 (skb_shinfo(skb)->nr_frags && 2084 !(features & NETIF_F_SG))); 2085 } 2086 2087 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, 2088 struct netdev_queue *txq) 2089 { 2090 const struct net_device_ops *ops = dev->netdev_ops; 2091 int rc = NETDEV_TX_OK; 2092 2093 if (likely(!skb->next)) { 2094 u32 features; 2095 2096 /* 2097 * If device doesn't need skb->dst, release it right now while 2098 * its hot in this cpu cache 2099 */ 2100 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 2101 skb_dst_drop(skb); 2102 2103 if (!list_empty(&ptype_all)) 2104 dev_queue_xmit_nit(skb, dev); 2105 2106 skb_orphan_try(skb); 2107 2108 features = netif_skb_features(skb); 2109 2110 if (vlan_tx_tag_present(skb) && 2111 !(features & NETIF_F_HW_VLAN_TX)) { 2112 skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb)); 2113 if (unlikely(!skb)) 2114 goto out; 2115 2116 skb->vlan_tci = 0; 2117 } 2118 2119 if (netif_needs_gso(skb, features)) { 2120 if (unlikely(dev_gso_segment(skb, features))) 2121 goto out_kfree_skb; 2122 if (skb->next) 2123 goto gso; 2124 } else { 2125 if (skb_needs_linearize(skb, features) && 2126 __skb_linearize(skb)) 2127 goto out_kfree_skb; 2128 2129 /* If packet is not checksummed and device does not 2130 * support checksumming for this protocol, complete 2131 * checksumming here. 2132 */ 2133 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2134 skb_set_transport_header(skb, 2135 skb_checksum_start_offset(skb)); 2136 if (!(features & NETIF_F_ALL_CSUM) && 2137 skb_checksum_help(skb)) 2138 goto out_kfree_skb; 2139 } 2140 } 2141 2142 rc = ops->ndo_start_xmit(skb, dev); 2143 trace_net_dev_xmit(skb, rc); 2144 if (rc == NETDEV_TX_OK) 2145 txq_trans_update(txq); 2146 return rc; 2147 } 2148 2149 gso: 2150 do { 2151 struct sk_buff *nskb = skb->next; 2152 2153 skb->next = nskb->next; 2154 nskb->next = NULL; 2155 2156 /* 2157 * If device doesn't need nskb->dst, release it right now while 2158 * its hot in this cpu cache 2159 */ 2160 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 2161 skb_dst_drop(nskb); 2162 2163 rc = ops->ndo_start_xmit(nskb, dev); 2164 trace_net_dev_xmit(nskb, rc); 2165 if (unlikely(rc != NETDEV_TX_OK)) { 2166 if (rc & ~NETDEV_TX_MASK) 2167 goto out_kfree_gso_skb; 2168 nskb->next = skb->next; 2169 skb->next = nskb; 2170 return rc; 2171 } 2172 txq_trans_update(txq); 2173 if (unlikely(netif_tx_queue_stopped(txq) && skb->next)) 2174 return NETDEV_TX_BUSY; 2175 } while (skb->next); 2176 2177 out_kfree_gso_skb: 2178 if (likely(skb->next == NULL)) 2179 skb->destructor = DEV_GSO_CB(skb)->destructor; 2180 out_kfree_skb: 2181 kfree_skb(skb); 2182 out: 2183 return rc; 2184 } 2185 2186 static u32 hashrnd __read_mostly; 2187 2188 /* 2189 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 2190 * to be used as a distribution range. 2191 */ 2192 u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb, 2193 unsigned int num_tx_queues) 2194 { 2195 u32 hash; 2196 u16 qoffset = 0; 2197 u16 qcount = num_tx_queues; 2198 2199 if (skb_rx_queue_recorded(skb)) { 2200 hash = skb_get_rx_queue(skb); 2201 while (unlikely(hash >= num_tx_queues)) 2202 hash -= num_tx_queues; 2203 return hash; 2204 } 2205 2206 if (dev->num_tc) { 2207 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 2208 qoffset = dev->tc_to_txq[tc].offset; 2209 qcount = dev->tc_to_txq[tc].count; 2210 } 2211 2212 if (skb->sk && skb->sk->sk_hash) 2213 hash = skb->sk->sk_hash; 2214 else 2215 hash = (__force u16) skb->protocol ^ skb->rxhash; 2216 hash = jhash_1word(hash, hashrnd); 2217 2218 return (u16) (((u64) hash * qcount) >> 32) + qoffset; 2219 } 2220 EXPORT_SYMBOL(__skb_tx_hash); 2221 2222 static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index) 2223 { 2224 if (unlikely(queue_index >= dev->real_num_tx_queues)) { 2225 if (net_ratelimit()) { 2226 pr_warning("%s selects TX queue %d, but " 2227 "real number of TX queues is %d\n", 2228 dev->name, queue_index, dev->real_num_tx_queues); 2229 } 2230 return 0; 2231 } 2232 return queue_index; 2233 } 2234 2235 static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb) 2236 { 2237 #ifdef CONFIG_XPS 2238 struct xps_dev_maps *dev_maps; 2239 struct xps_map *map; 2240 int queue_index = -1; 2241 2242 rcu_read_lock(); 2243 dev_maps = rcu_dereference(dev->xps_maps); 2244 if (dev_maps) { 2245 map = rcu_dereference( 2246 dev_maps->cpu_map[raw_smp_processor_id()]); 2247 if (map) { 2248 if (map->len == 1) 2249 queue_index = map->queues[0]; 2250 else { 2251 u32 hash; 2252 if (skb->sk && skb->sk->sk_hash) 2253 hash = skb->sk->sk_hash; 2254 else 2255 hash = (__force u16) skb->protocol ^ 2256 skb->rxhash; 2257 hash = jhash_1word(hash, hashrnd); 2258 queue_index = map->queues[ 2259 ((u64)hash * map->len) >> 32]; 2260 } 2261 if (unlikely(queue_index >= dev->real_num_tx_queues)) 2262 queue_index = -1; 2263 } 2264 } 2265 rcu_read_unlock(); 2266 2267 return queue_index; 2268 #else 2269 return -1; 2270 #endif 2271 } 2272 2273 static struct netdev_queue *dev_pick_tx(struct net_device *dev, 2274 struct sk_buff *skb) 2275 { 2276 int queue_index; 2277 const struct net_device_ops *ops = dev->netdev_ops; 2278 2279 if (dev->real_num_tx_queues == 1) 2280 queue_index = 0; 2281 else if (ops->ndo_select_queue) { 2282 queue_index = ops->ndo_select_queue(dev, skb); 2283 queue_index = dev_cap_txqueue(dev, queue_index); 2284 } else { 2285 struct sock *sk = skb->sk; 2286 queue_index = sk_tx_queue_get(sk); 2287 2288 if (queue_index < 0 || skb->ooo_okay || 2289 queue_index >= dev->real_num_tx_queues) { 2290 int old_index = queue_index; 2291 2292 queue_index = get_xps_queue(dev, skb); 2293 if (queue_index < 0) 2294 queue_index = skb_tx_hash(dev, skb); 2295 2296 if (queue_index != old_index && sk) { 2297 struct dst_entry *dst = 2298 rcu_dereference_check(sk->sk_dst_cache, 1); 2299 2300 if (dst && skb_dst(skb) == dst) 2301 sk_tx_queue_set(sk, queue_index); 2302 } 2303 } 2304 } 2305 2306 skb_set_queue_mapping(skb, queue_index); 2307 return netdev_get_tx_queue(dev, queue_index); 2308 } 2309 2310 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 2311 struct net_device *dev, 2312 struct netdev_queue *txq) 2313 { 2314 spinlock_t *root_lock = qdisc_lock(q); 2315 bool contended; 2316 int rc; 2317 2318 qdisc_skb_cb(skb)->pkt_len = skb->len; 2319 qdisc_calculate_pkt_len(skb, q); 2320 /* 2321 * Heuristic to force contended enqueues to serialize on a 2322 * separate lock before trying to get qdisc main lock. 2323 * This permits __QDISC_STATE_RUNNING owner to get the lock more often 2324 * and dequeue packets faster. 2325 */ 2326 contended = qdisc_is_running(q); 2327 if (unlikely(contended)) 2328 spin_lock(&q->busylock); 2329 2330 spin_lock(root_lock); 2331 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 2332 kfree_skb(skb); 2333 rc = NET_XMIT_DROP; 2334 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 2335 qdisc_run_begin(q)) { 2336 /* 2337 * This is a work-conserving queue; there are no old skbs 2338 * waiting to be sent out; and the qdisc is not running - 2339 * xmit the skb directly. 2340 */ 2341 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE)) 2342 skb_dst_force(skb); 2343 2344 qdisc_bstats_update(q, skb); 2345 2346 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) { 2347 if (unlikely(contended)) { 2348 spin_unlock(&q->busylock); 2349 contended = false; 2350 } 2351 __qdisc_run(q); 2352 } else 2353 qdisc_run_end(q); 2354 2355 rc = NET_XMIT_SUCCESS; 2356 } else { 2357 skb_dst_force(skb); 2358 rc = q->enqueue(skb, q) & NET_XMIT_MASK; 2359 if (qdisc_run_begin(q)) { 2360 if (unlikely(contended)) { 2361 spin_unlock(&q->busylock); 2362 contended = false; 2363 } 2364 __qdisc_run(q); 2365 } 2366 } 2367 spin_unlock(root_lock); 2368 if (unlikely(contended)) 2369 spin_unlock(&q->busylock); 2370 return rc; 2371 } 2372 2373 static DEFINE_PER_CPU(int, xmit_recursion); 2374 #define RECURSION_LIMIT 10 2375 2376 /** 2377 * dev_queue_xmit - transmit a buffer 2378 * @skb: buffer to transmit 2379 * 2380 * Queue a buffer for transmission to a network device. The caller must 2381 * have set the device and priority and built the buffer before calling 2382 * this function. The function can be called from an interrupt. 2383 * 2384 * A negative errno code is returned on a failure. A success does not 2385 * guarantee the frame will be transmitted as it may be dropped due 2386 * to congestion or traffic shaping. 2387 * 2388 * ----------------------------------------------------------------------------------- 2389 * I notice this method can also return errors from the queue disciplines, 2390 * including NET_XMIT_DROP, which is a positive value. So, errors can also 2391 * be positive. 2392 * 2393 * Regardless of the return value, the skb is consumed, so it is currently 2394 * difficult to retry a send to this method. (You can bump the ref count 2395 * before sending to hold a reference for retry if you are careful.) 2396 * 2397 * When calling this method, interrupts MUST be enabled. This is because 2398 * the BH enable code must have IRQs enabled so that it will not deadlock. 2399 * --BLG 2400 */ 2401 int dev_queue_xmit(struct sk_buff *skb) 2402 { 2403 struct net_device *dev = skb->dev; 2404 struct netdev_queue *txq; 2405 struct Qdisc *q; 2406 int rc = -ENOMEM; 2407 2408 /* Disable soft irqs for various locks below. Also 2409 * stops preemption for RCU. 2410 */ 2411 rcu_read_lock_bh(); 2412 2413 txq = dev_pick_tx(dev, skb); 2414 q = rcu_dereference_bh(txq->qdisc); 2415 2416 #ifdef CONFIG_NET_CLS_ACT 2417 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS); 2418 #endif 2419 trace_net_dev_queue(skb); 2420 if (q->enqueue) { 2421 rc = __dev_xmit_skb(skb, q, dev, txq); 2422 goto out; 2423 } 2424 2425 /* The device has no queue. Common case for software devices: 2426 loopback, all the sorts of tunnels... 2427 2428 Really, it is unlikely that netif_tx_lock protection is necessary 2429 here. (f.e. loopback and IP tunnels are clean ignoring statistics 2430 counters.) 2431 However, it is possible, that they rely on protection 2432 made by us here. 2433 2434 Check this and shot the lock. It is not prone from deadlocks. 2435 Either shot noqueue qdisc, it is even simpler 8) 2436 */ 2437 if (dev->flags & IFF_UP) { 2438 int cpu = smp_processor_id(); /* ok because BHs are off */ 2439 2440 if (txq->xmit_lock_owner != cpu) { 2441 2442 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT) 2443 goto recursion_alert; 2444 2445 HARD_TX_LOCK(dev, txq, cpu); 2446 2447 if (!netif_tx_queue_stopped(txq)) { 2448 __this_cpu_inc(xmit_recursion); 2449 rc = dev_hard_start_xmit(skb, dev, txq); 2450 __this_cpu_dec(xmit_recursion); 2451 if (dev_xmit_complete(rc)) { 2452 HARD_TX_UNLOCK(dev, txq); 2453 goto out; 2454 } 2455 } 2456 HARD_TX_UNLOCK(dev, txq); 2457 if (net_ratelimit()) 2458 printk(KERN_CRIT "Virtual device %s asks to " 2459 "queue packet!\n", dev->name); 2460 } else { 2461 /* Recursion is detected! It is possible, 2462 * unfortunately 2463 */ 2464 recursion_alert: 2465 if (net_ratelimit()) 2466 printk(KERN_CRIT "Dead loop on virtual device " 2467 "%s, fix it urgently!\n", dev->name); 2468 } 2469 } 2470 2471 rc = -ENETDOWN; 2472 rcu_read_unlock_bh(); 2473 2474 kfree_skb(skb); 2475 return rc; 2476 out: 2477 rcu_read_unlock_bh(); 2478 return rc; 2479 } 2480 EXPORT_SYMBOL(dev_queue_xmit); 2481 2482 2483 /*======================================================================= 2484 Receiver routines 2485 =======================================================================*/ 2486 2487 int netdev_max_backlog __read_mostly = 1000; 2488 int netdev_tstamp_prequeue __read_mostly = 1; 2489 int netdev_budget __read_mostly = 300; 2490 int weight_p __read_mostly = 64; /* old backlog weight */ 2491 2492 /* Called with irq disabled */ 2493 static inline void ____napi_schedule(struct softnet_data *sd, 2494 struct napi_struct *napi) 2495 { 2496 list_add_tail(&napi->poll_list, &sd->poll_list); 2497 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2498 } 2499 2500 /* 2501 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses 2502 * and src/dst port numbers. Returns a non-zero hash number on success 2503 * and 0 on failure. 2504 */ 2505 __u32 __skb_get_rxhash(struct sk_buff *skb) 2506 { 2507 int nhoff, hash = 0, poff; 2508 const struct ipv6hdr *ip6; 2509 const struct iphdr *ip; 2510 u8 ip_proto; 2511 u32 addr1, addr2, ihl; 2512 union { 2513 u32 v32; 2514 u16 v16[2]; 2515 } ports; 2516 2517 nhoff = skb_network_offset(skb); 2518 2519 switch (skb->protocol) { 2520 case __constant_htons(ETH_P_IP): 2521 if (!pskb_may_pull(skb, sizeof(*ip) + nhoff)) 2522 goto done; 2523 2524 ip = (const struct iphdr *) (skb->data + nhoff); 2525 if (ip->frag_off & htons(IP_MF | IP_OFFSET)) 2526 ip_proto = 0; 2527 else 2528 ip_proto = ip->protocol; 2529 addr1 = (__force u32) ip->saddr; 2530 addr2 = (__force u32) ip->daddr; 2531 ihl = ip->ihl; 2532 break; 2533 case __constant_htons(ETH_P_IPV6): 2534 if (!pskb_may_pull(skb, sizeof(*ip6) + nhoff)) 2535 goto done; 2536 2537 ip6 = (const struct ipv6hdr *) (skb->data + nhoff); 2538 ip_proto = ip6->nexthdr; 2539 addr1 = (__force u32) ip6->saddr.s6_addr32[3]; 2540 addr2 = (__force u32) ip6->daddr.s6_addr32[3]; 2541 ihl = (40 >> 2); 2542 break; 2543 default: 2544 goto done; 2545 } 2546 2547 ports.v32 = 0; 2548 poff = proto_ports_offset(ip_proto); 2549 if (poff >= 0) { 2550 nhoff += ihl * 4 + poff; 2551 if (pskb_may_pull(skb, nhoff + 4)) { 2552 ports.v32 = * (__force u32 *) (skb->data + nhoff); 2553 if (ports.v16[1] < ports.v16[0]) 2554 swap(ports.v16[0], ports.v16[1]); 2555 } 2556 } 2557 2558 /* get a consistent hash (same value on both flow directions) */ 2559 if (addr2 < addr1) 2560 swap(addr1, addr2); 2561 2562 hash = jhash_3words(addr1, addr2, ports.v32, hashrnd); 2563 if (!hash) 2564 hash = 1; 2565 2566 done: 2567 return hash; 2568 } 2569 EXPORT_SYMBOL(__skb_get_rxhash); 2570 2571 #ifdef CONFIG_RPS 2572 2573 /* One global table that all flow-based protocols share. */ 2574 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 2575 EXPORT_SYMBOL(rps_sock_flow_table); 2576 2577 static struct rps_dev_flow * 2578 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 2579 struct rps_dev_flow *rflow, u16 next_cpu) 2580 { 2581 u16 tcpu; 2582 2583 tcpu = rflow->cpu = next_cpu; 2584 if (tcpu != RPS_NO_CPU) { 2585 #ifdef CONFIG_RFS_ACCEL 2586 struct netdev_rx_queue *rxqueue; 2587 struct rps_dev_flow_table *flow_table; 2588 struct rps_dev_flow *old_rflow; 2589 u32 flow_id; 2590 u16 rxq_index; 2591 int rc; 2592 2593 /* Should we steer this flow to a different hardware queue? */ 2594 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 2595 !(dev->features & NETIF_F_NTUPLE)) 2596 goto out; 2597 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 2598 if (rxq_index == skb_get_rx_queue(skb)) 2599 goto out; 2600 2601 rxqueue = dev->_rx + rxq_index; 2602 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2603 if (!flow_table) 2604 goto out; 2605 flow_id = skb->rxhash & flow_table->mask; 2606 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 2607 rxq_index, flow_id); 2608 if (rc < 0) 2609 goto out; 2610 old_rflow = rflow; 2611 rflow = &flow_table->flows[flow_id]; 2612 rflow->cpu = next_cpu; 2613 rflow->filter = rc; 2614 if (old_rflow->filter == rflow->filter) 2615 old_rflow->filter = RPS_NO_FILTER; 2616 out: 2617 #endif 2618 rflow->last_qtail = 2619 per_cpu(softnet_data, tcpu).input_queue_head; 2620 } 2621 2622 return rflow; 2623 } 2624 2625 /* 2626 * get_rps_cpu is called from netif_receive_skb and returns the target 2627 * CPU from the RPS map of the receiving queue for a given skb. 2628 * rcu_read_lock must be held on entry. 2629 */ 2630 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 2631 struct rps_dev_flow **rflowp) 2632 { 2633 struct netdev_rx_queue *rxqueue; 2634 struct rps_map *map; 2635 struct rps_dev_flow_table *flow_table; 2636 struct rps_sock_flow_table *sock_flow_table; 2637 int cpu = -1; 2638 u16 tcpu; 2639 2640 if (skb_rx_queue_recorded(skb)) { 2641 u16 index = skb_get_rx_queue(skb); 2642 if (unlikely(index >= dev->real_num_rx_queues)) { 2643 WARN_ONCE(dev->real_num_rx_queues > 1, 2644 "%s received packet on queue %u, but number " 2645 "of RX queues is %u\n", 2646 dev->name, index, dev->real_num_rx_queues); 2647 goto done; 2648 } 2649 rxqueue = dev->_rx + index; 2650 } else 2651 rxqueue = dev->_rx; 2652 2653 map = rcu_dereference(rxqueue->rps_map); 2654 if (map) { 2655 if (map->len == 1 && 2656 !rcu_dereference_raw(rxqueue->rps_flow_table)) { 2657 tcpu = map->cpus[0]; 2658 if (cpu_online(tcpu)) 2659 cpu = tcpu; 2660 goto done; 2661 } 2662 } else if (!rcu_dereference_raw(rxqueue->rps_flow_table)) { 2663 goto done; 2664 } 2665 2666 skb_reset_network_header(skb); 2667 if (!skb_get_rxhash(skb)) 2668 goto done; 2669 2670 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2671 sock_flow_table = rcu_dereference(rps_sock_flow_table); 2672 if (flow_table && sock_flow_table) { 2673 u16 next_cpu; 2674 struct rps_dev_flow *rflow; 2675 2676 rflow = &flow_table->flows[skb->rxhash & flow_table->mask]; 2677 tcpu = rflow->cpu; 2678 2679 next_cpu = sock_flow_table->ents[skb->rxhash & 2680 sock_flow_table->mask]; 2681 2682 /* 2683 * If the desired CPU (where last recvmsg was done) is 2684 * different from current CPU (one in the rx-queue flow 2685 * table entry), switch if one of the following holds: 2686 * - Current CPU is unset (equal to RPS_NO_CPU). 2687 * - Current CPU is offline. 2688 * - The current CPU's queue tail has advanced beyond the 2689 * last packet that was enqueued using this table entry. 2690 * This guarantees that all previous packets for the flow 2691 * have been dequeued, thus preserving in order delivery. 2692 */ 2693 if (unlikely(tcpu != next_cpu) && 2694 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) || 2695 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 2696 rflow->last_qtail)) >= 0)) 2697 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 2698 2699 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) { 2700 *rflowp = rflow; 2701 cpu = tcpu; 2702 goto done; 2703 } 2704 } 2705 2706 if (map) { 2707 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32]; 2708 2709 if (cpu_online(tcpu)) { 2710 cpu = tcpu; 2711 goto done; 2712 } 2713 } 2714 2715 done: 2716 return cpu; 2717 } 2718 2719 #ifdef CONFIG_RFS_ACCEL 2720 2721 /** 2722 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 2723 * @dev: Device on which the filter was set 2724 * @rxq_index: RX queue index 2725 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 2726 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 2727 * 2728 * Drivers that implement ndo_rx_flow_steer() should periodically call 2729 * this function for each installed filter and remove the filters for 2730 * which it returns %true. 2731 */ 2732 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 2733 u32 flow_id, u16 filter_id) 2734 { 2735 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 2736 struct rps_dev_flow_table *flow_table; 2737 struct rps_dev_flow *rflow; 2738 bool expire = true; 2739 int cpu; 2740 2741 rcu_read_lock(); 2742 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2743 if (flow_table && flow_id <= flow_table->mask) { 2744 rflow = &flow_table->flows[flow_id]; 2745 cpu = ACCESS_ONCE(rflow->cpu); 2746 if (rflow->filter == filter_id && cpu != RPS_NO_CPU && 2747 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 2748 rflow->last_qtail) < 2749 (int)(10 * flow_table->mask))) 2750 expire = false; 2751 } 2752 rcu_read_unlock(); 2753 return expire; 2754 } 2755 EXPORT_SYMBOL(rps_may_expire_flow); 2756 2757 #endif /* CONFIG_RFS_ACCEL */ 2758 2759 /* Called from hardirq (IPI) context */ 2760 static void rps_trigger_softirq(void *data) 2761 { 2762 struct softnet_data *sd = data; 2763 2764 ____napi_schedule(sd, &sd->backlog); 2765 sd->received_rps++; 2766 } 2767 2768 #endif /* CONFIG_RPS */ 2769 2770 /* 2771 * Check if this softnet_data structure is another cpu one 2772 * If yes, queue it to our IPI list and return 1 2773 * If no, return 0 2774 */ 2775 static int rps_ipi_queued(struct softnet_data *sd) 2776 { 2777 #ifdef CONFIG_RPS 2778 struct softnet_data *mysd = &__get_cpu_var(softnet_data); 2779 2780 if (sd != mysd) { 2781 sd->rps_ipi_next = mysd->rps_ipi_list; 2782 mysd->rps_ipi_list = sd; 2783 2784 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2785 return 1; 2786 } 2787 #endif /* CONFIG_RPS */ 2788 return 0; 2789 } 2790 2791 /* 2792 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 2793 * queue (may be a remote CPU queue). 2794 */ 2795 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 2796 unsigned int *qtail) 2797 { 2798 struct softnet_data *sd; 2799 unsigned long flags; 2800 2801 sd = &per_cpu(softnet_data, cpu); 2802 2803 local_irq_save(flags); 2804 2805 rps_lock(sd); 2806 if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) { 2807 if (skb_queue_len(&sd->input_pkt_queue)) { 2808 enqueue: 2809 __skb_queue_tail(&sd->input_pkt_queue, skb); 2810 input_queue_tail_incr_save(sd, qtail); 2811 rps_unlock(sd); 2812 local_irq_restore(flags); 2813 return NET_RX_SUCCESS; 2814 } 2815 2816 /* Schedule NAPI for backlog device 2817 * We can use non atomic operation since we own the queue lock 2818 */ 2819 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { 2820 if (!rps_ipi_queued(sd)) 2821 ____napi_schedule(sd, &sd->backlog); 2822 } 2823 goto enqueue; 2824 } 2825 2826 sd->dropped++; 2827 rps_unlock(sd); 2828 2829 local_irq_restore(flags); 2830 2831 atomic_long_inc(&skb->dev->rx_dropped); 2832 kfree_skb(skb); 2833 return NET_RX_DROP; 2834 } 2835 2836 /** 2837 * netif_rx - post buffer to the network code 2838 * @skb: buffer to post 2839 * 2840 * This function receives a packet from a device driver and queues it for 2841 * the upper (protocol) levels to process. It always succeeds. The buffer 2842 * may be dropped during processing for congestion control or by the 2843 * protocol layers. 2844 * 2845 * return values: 2846 * NET_RX_SUCCESS (no congestion) 2847 * NET_RX_DROP (packet was dropped) 2848 * 2849 */ 2850 2851 int netif_rx(struct sk_buff *skb) 2852 { 2853 int ret; 2854 2855 /* if netpoll wants it, pretend we never saw it */ 2856 if (netpoll_rx(skb)) 2857 return NET_RX_DROP; 2858 2859 if (netdev_tstamp_prequeue) 2860 net_timestamp_check(skb); 2861 2862 trace_netif_rx(skb); 2863 #ifdef CONFIG_RPS 2864 { 2865 struct rps_dev_flow voidflow, *rflow = &voidflow; 2866 int cpu; 2867 2868 preempt_disable(); 2869 rcu_read_lock(); 2870 2871 cpu = get_rps_cpu(skb->dev, skb, &rflow); 2872 if (cpu < 0) 2873 cpu = smp_processor_id(); 2874 2875 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 2876 2877 rcu_read_unlock(); 2878 preempt_enable(); 2879 } 2880 #else 2881 { 2882 unsigned int qtail; 2883 ret = enqueue_to_backlog(skb, get_cpu(), &qtail); 2884 put_cpu(); 2885 } 2886 #endif 2887 return ret; 2888 } 2889 EXPORT_SYMBOL(netif_rx); 2890 2891 int netif_rx_ni(struct sk_buff *skb) 2892 { 2893 int err; 2894 2895 preempt_disable(); 2896 err = netif_rx(skb); 2897 if (local_softirq_pending()) 2898 do_softirq(); 2899 preempt_enable(); 2900 2901 return err; 2902 } 2903 EXPORT_SYMBOL(netif_rx_ni); 2904 2905 static void net_tx_action(struct softirq_action *h) 2906 { 2907 struct softnet_data *sd = &__get_cpu_var(softnet_data); 2908 2909 if (sd->completion_queue) { 2910 struct sk_buff *clist; 2911 2912 local_irq_disable(); 2913 clist = sd->completion_queue; 2914 sd->completion_queue = NULL; 2915 local_irq_enable(); 2916 2917 while (clist) { 2918 struct sk_buff *skb = clist; 2919 clist = clist->next; 2920 2921 WARN_ON(atomic_read(&skb->users)); 2922 trace_kfree_skb(skb, net_tx_action); 2923 __kfree_skb(skb); 2924 } 2925 } 2926 2927 if (sd->output_queue) { 2928 struct Qdisc *head; 2929 2930 local_irq_disable(); 2931 head = sd->output_queue; 2932 sd->output_queue = NULL; 2933 sd->output_queue_tailp = &sd->output_queue; 2934 local_irq_enable(); 2935 2936 while (head) { 2937 struct Qdisc *q = head; 2938 spinlock_t *root_lock; 2939 2940 head = head->next_sched; 2941 2942 root_lock = qdisc_lock(q); 2943 if (spin_trylock(root_lock)) { 2944 smp_mb__before_clear_bit(); 2945 clear_bit(__QDISC_STATE_SCHED, 2946 &q->state); 2947 qdisc_run(q); 2948 spin_unlock(root_lock); 2949 } else { 2950 if (!test_bit(__QDISC_STATE_DEACTIVATED, 2951 &q->state)) { 2952 __netif_reschedule(q); 2953 } else { 2954 smp_mb__before_clear_bit(); 2955 clear_bit(__QDISC_STATE_SCHED, 2956 &q->state); 2957 } 2958 } 2959 } 2960 } 2961 } 2962 2963 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \ 2964 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)) 2965 /* This hook is defined here for ATM LANE */ 2966 int (*br_fdb_test_addr_hook)(struct net_device *dev, 2967 unsigned char *addr) __read_mostly; 2968 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 2969 #endif 2970 2971 #ifdef CONFIG_NET_CLS_ACT 2972 /* TODO: Maybe we should just force sch_ingress to be compiled in 2973 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions 2974 * a compare and 2 stores extra right now if we dont have it on 2975 * but have CONFIG_NET_CLS_ACT 2976 * NOTE: This doesn't stop any functionality; if you dont have 2977 * the ingress scheduler, you just can't add policies on ingress. 2978 * 2979 */ 2980 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq) 2981 { 2982 struct net_device *dev = skb->dev; 2983 u32 ttl = G_TC_RTTL(skb->tc_verd); 2984 int result = TC_ACT_OK; 2985 struct Qdisc *q; 2986 2987 if (unlikely(MAX_RED_LOOP < ttl++)) { 2988 if (net_ratelimit()) 2989 pr_warning( "Redir loop detected Dropping packet (%d->%d)\n", 2990 skb->skb_iif, dev->ifindex); 2991 return TC_ACT_SHOT; 2992 } 2993 2994 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl); 2995 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS); 2996 2997 q = rxq->qdisc; 2998 if (q != &noop_qdisc) { 2999 spin_lock(qdisc_lock(q)); 3000 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) 3001 result = qdisc_enqueue_root(skb, q); 3002 spin_unlock(qdisc_lock(q)); 3003 } 3004 3005 return result; 3006 } 3007 3008 static inline struct sk_buff *handle_ing(struct sk_buff *skb, 3009 struct packet_type **pt_prev, 3010 int *ret, struct net_device *orig_dev) 3011 { 3012 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue); 3013 3014 if (!rxq || rxq->qdisc == &noop_qdisc) 3015 goto out; 3016 3017 if (*pt_prev) { 3018 *ret = deliver_skb(skb, *pt_prev, orig_dev); 3019 *pt_prev = NULL; 3020 } 3021 3022 switch (ing_filter(skb, rxq)) { 3023 case TC_ACT_SHOT: 3024 case TC_ACT_STOLEN: 3025 kfree_skb(skb); 3026 return NULL; 3027 } 3028 3029 out: 3030 skb->tc_verd = 0; 3031 return skb; 3032 } 3033 #endif 3034 3035 /** 3036 * netdev_rx_handler_register - register receive handler 3037 * @dev: device to register a handler for 3038 * @rx_handler: receive handler to register 3039 * @rx_handler_data: data pointer that is used by rx handler 3040 * 3041 * Register a receive hander for a device. This handler will then be 3042 * called from __netif_receive_skb. A negative errno code is returned 3043 * on a failure. 3044 * 3045 * The caller must hold the rtnl_mutex. 3046 * 3047 * For a general description of rx_handler, see enum rx_handler_result. 3048 */ 3049 int netdev_rx_handler_register(struct net_device *dev, 3050 rx_handler_func_t *rx_handler, 3051 void *rx_handler_data) 3052 { 3053 ASSERT_RTNL(); 3054 3055 if (dev->rx_handler) 3056 return -EBUSY; 3057 3058 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 3059 rcu_assign_pointer(dev->rx_handler, rx_handler); 3060 3061 return 0; 3062 } 3063 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 3064 3065 /** 3066 * netdev_rx_handler_unregister - unregister receive handler 3067 * @dev: device to unregister a handler from 3068 * 3069 * Unregister a receive hander from a device. 3070 * 3071 * The caller must hold the rtnl_mutex. 3072 */ 3073 void netdev_rx_handler_unregister(struct net_device *dev) 3074 { 3075 3076 ASSERT_RTNL(); 3077 rcu_assign_pointer(dev->rx_handler, NULL); 3078 rcu_assign_pointer(dev->rx_handler_data, NULL); 3079 } 3080 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 3081 3082 static int __netif_receive_skb(struct sk_buff *skb) 3083 { 3084 struct packet_type *ptype, *pt_prev; 3085 rx_handler_func_t *rx_handler; 3086 struct net_device *orig_dev; 3087 struct net_device *null_or_dev; 3088 bool deliver_exact = false; 3089 int ret = NET_RX_DROP; 3090 __be16 type; 3091 3092 if (!netdev_tstamp_prequeue) 3093 net_timestamp_check(skb); 3094 3095 trace_netif_receive_skb(skb); 3096 3097 /* if we've gotten here through NAPI, check netpoll */ 3098 if (netpoll_receive_skb(skb)) 3099 return NET_RX_DROP; 3100 3101 if (!skb->skb_iif) 3102 skb->skb_iif = skb->dev->ifindex; 3103 orig_dev = skb->dev; 3104 3105 skb_reset_network_header(skb); 3106 skb_reset_transport_header(skb); 3107 skb->mac_len = skb->network_header - skb->mac_header; 3108 3109 pt_prev = NULL; 3110 3111 rcu_read_lock(); 3112 3113 another_round: 3114 3115 __this_cpu_inc(softnet_data.processed); 3116 3117 if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) { 3118 skb = vlan_untag(skb); 3119 if (unlikely(!skb)) 3120 goto out; 3121 } 3122 3123 #ifdef CONFIG_NET_CLS_ACT 3124 if (skb->tc_verd & TC_NCLS) { 3125 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); 3126 goto ncls; 3127 } 3128 #endif 3129 3130 list_for_each_entry_rcu(ptype, &ptype_all, list) { 3131 if (!ptype->dev || ptype->dev == skb->dev) { 3132 if (pt_prev) 3133 ret = deliver_skb(skb, pt_prev, orig_dev); 3134 pt_prev = ptype; 3135 } 3136 } 3137 3138 #ifdef CONFIG_NET_CLS_ACT 3139 skb = handle_ing(skb, &pt_prev, &ret, orig_dev); 3140 if (!skb) 3141 goto out; 3142 ncls: 3143 #endif 3144 3145 rx_handler = rcu_dereference(skb->dev->rx_handler); 3146 if (rx_handler) { 3147 if (pt_prev) { 3148 ret = deliver_skb(skb, pt_prev, orig_dev); 3149 pt_prev = NULL; 3150 } 3151 switch (rx_handler(&skb)) { 3152 case RX_HANDLER_CONSUMED: 3153 goto out; 3154 case RX_HANDLER_ANOTHER: 3155 goto another_round; 3156 case RX_HANDLER_EXACT: 3157 deliver_exact = true; 3158 case RX_HANDLER_PASS: 3159 break; 3160 default: 3161 BUG(); 3162 } 3163 } 3164 3165 if (vlan_tx_tag_present(skb)) { 3166 if (pt_prev) { 3167 ret = deliver_skb(skb, pt_prev, orig_dev); 3168 pt_prev = NULL; 3169 } 3170 if (vlan_do_receive(&skb)) { 3171 ret = __netif_receive_skb(skb); 3172 goto out; 3173 } else if (unlikely(!skb)) 3174 goto out; 3175 } 3176 3177 /* deliver only exact match when indicated */ 3178 null_or_dev = deliver_exact ? skb->dev : NULL; 3179 3180 type = skb->protocol; 3181 list_for_each_entry_rcu(ptype, 3182 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 3183 if (ptype->type == type && 3184 (ptype->dev == null_or_dev || ptype->dev == skb->dev || 3185 ptype->dev == orig_dev)) { 3186 if (pt_prev) 3187 ret = deliver_skb(skb, pt_prev, orig_dev); 3188 pt_prev = ptype; 3189 } 3190 } 3191 3192 if (pt_prev) { 3193 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 3194 } else { 3195 atomic_long_inc(&skb->dev->rx_dropped); 3196 kfree_skb(skb); 3197 /* Jamal, now you will not able to escape explaining 3198 * me how you were going to use this. :-) 3199 */ 3200 ret = NET_RX_DROP; 3201 } 3202 3203 out: 3204 rcu_read_unlock(); 3205 return ret; 3206 } 3207 3208 /** 3209 * netif_receive_skb - process receive buffer from network 3210 * @skb: buffer to process 3211 * 3212 * netif_receive_skb() is the main receive data processing function. 3213 * It always succeeds. The buffer may be dropped during processing 3214 * for congestion control or by the protocol layers. 3215 * 3216 * This function may only be called from softirq context and interrupts 3217 * should be enabled. 3218 * 3219 * Return values (usually ignored): 3220 * NET_RX_SUCCESS: no congestion 3221 * NET_RX_DROP: packet was dropped 3222 */ 3223 int netif_receive_skb(struct sk_buff *skb) 3224 { 3225 if (netdev_tstamp_prequeue) 3226 net_timestamp_check(skb); 3227 3228 if (skb_defer_rx_timestamp(skb)) 3229 return NET_RX_SUCCESS; 3230 3231 #ifdef CONFIG_RPS 3232 { 3233 struct rps_dev_flow voidflow, *rflow = &voidflow; 3234 int cpu, ret; 3235 3236 rcu_read_lock(); 3237 3238 cpu = get_rps_cpu(skb->dev, skb, &rflow); 3239 3240 if (cpu >= 0) { 3241 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 3242 rcu_read_unlock(); 3243 } else { 3244 rcu_read_unlock(); 3245 ret = __netif_receive_skb(skb); 3246 } 3247 3248 return ret; 3249 } 3250 #else 3251 return __netif_receive_skb(skb); 3252 #endif 3253 } 3254 EXPORT_SYMBOL(netif_receive_skb); 3255 3256 /* Network device is going away, flush any packets still pending 3257 * Called with irqs disabled. 3258 */ 3259 static void flush_backlog(void *arg) 3260 { 3261 struct net_device *dev = arg; 3262 struct softnet_data *sd = &__get_cpu_var(softnet_data); 3263 struct sk_buff *skb, *tmp; 3264 3265 rps_lock(sd); 3266 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 3267 if (skb->dev == dev) { 3268 __skb_unlink(skb, &sd->input_pkt_queue); 3269 kfree_skb(skb); 3270 input_queue_head_incr(sd); 3271 } 3272 } 3273 rps_unlock(sd); 3274 3275 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 3276 if (skb->dev == dev) { 3277 __skb_unlink(skb, &sd->process_queue); 3278 kfree_skb(skb); 3279 input_queue_head_incr(sd); 3280 } 3281 } 3282 } 3283 3284 static int napi_gro_complete(struct sk_buff *skb) 3285 { 3286 struct packet_type *ptype; 3287 __be16 type = skb->protocol; 3288 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 3289 int err = -ENOENT; 3290 3291 if (NAPI_GRO_CB(skb)->count == 1) { 3292 skb_shinfo(skb)->gso_size = 0; 3293 goto out; 3294 } 3295 3296 rcu_read_lock(); 3297 list_for_each_entry_rcu(ptype, head, list) { 3298 if (ptype->type != type || ptype->dev || !ptype->gro_complete) 3299 continue; 3300 3301 err = ptype->gro_complete(skb); 3302 break; 3303 } 3304 rcu_read_unlock(); 3305 3306 if (err) { 3307 WARN_ON(&ptype->list == head); 3308 kfree_skb(skb); 3309 return NET_RX_SUCCESS; 3310 } 3311 3312 out: 3313 return netif_receive_skb(skb); 3314 } 3315 3316 inline void napi_gro_flush(struct napi_struct *napi) 3317 { 3318 struct sk_buff *skb, *next; 3319 3320 for (skb = napi->gro_list; skb; skb = next) { 3321 next = skb->next; 3322 skb->next = NULL; 3323 napi_gro_complete(skb); 3324 } 3325 3326 napi->gro_count = 0; 3327 napi->gro_list = NULL; 3328 } 3329 EXPORT_SYMBOL(napi_gro_flush); 3330 3331 enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3332 { 3333 struct sk_buff **pp = NULL; 3334 struct packet_type *ptype; 3335 __be16 type = skb->protocol; 3336 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 3337 int same_flow; 3338 int mac_len; 3339 enum gro_result ret; 3340 3341 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb)) 3342 goto normal; 3343 3344 if (skb_is_gso(skb) || skb_has_frag_list(skb)) 3345 goto normal; 3346 3347 rcu_read_lock(); 3348 list_for_each_entry_rcu(ptype, head, list) { 3349 if (ptype->type != type || ptype->dev || !ptype->gro_receive) 3350 continue; 3351 3352 skb_set_network_header(skb, skb_gro_offset(skb)); 3353 mac_len = skb->network_header - skb->mac_header; 3354 skb->mac_len = mac_len; 3355 NAPI_GRO_CB(skb)->same_flow = 0; 3356 NAPI_GRO_CB(skb)->flush = 0; 3357 NAPI_GRO_CB(skb)->free = 0; 3358 3359 pp = ptype->gro_receive(&napi->gro_list, skb); 3360 break; 3361 } 3362 rcu_read_unlock(); 3363 3364 if (&ptype->list == head) 3365 goto normal; 3366 3367 same_flow = NAPI_GRO_CB(skb)->same_flow; 3368 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; 3369 3370 if (pp) { 3371 struct sk_buff *nskb = *pp; 3372 3373 *pp = nskb->next; 3374 nskb->next = NULL; 3375 napi_gro_complete(nskb); 3376 napi->gro_count--; 3377 } 3378 3379 if (same_flow) 3380 goto ok; 3381 3382 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS) 3383 goto normal; 3384 3385 napi->gro_count++; 3386 NAPI_GRO_CB(skb)->count = 1; 3387 skb_shinfo(skb)->gso_size = skb_gro_len(skb); 3388 skb->next = napi->gro_list; 3389 napi->gro_list = skb; 3390 ret = GRO_HELD; 3391 3392 pull: 3393 if (skb_headlen(skb) < skb_gro_offset(skb)) { 3394 int grow = skb_gro_offset(skb) - skb_headlen(skb); 3395 3396 BUG_ON(skb->end - skb->tail < grow); 3397 3398 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); 3399 3400 skb->tail += grow; 3401 skb->data_len -= grow; 3402 3403 skb_shinfo(skb)->frags[0].page_offset += grow; 3404 skb_shinfo(skb)->frags[0].size -= grow; 3405 3406 if (unlikely(!skb_shinfo(skb)->frags[0].size)) { 3407 put_page(skb_shinfo(skb)->frags[0].page); 3408 memmove(skb_shinfo(skb)->frags, 3409 skb_shinfo(skb)->frags + 1, 3410 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t)); 3411 } 3412 } 3413 3414 ok: 3415 return ret; 3416 3417 normal: 3418 ret = GRO_NORMAL; 3419 goto pull; 3420 } 3421 EXPORT_SYMBOL(dev_gro_receive); 3422 3423 static inline gro_result_t 3424 __napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3425 { 3426 struct sk_buff *p; 3427 3428 for (p = napi->gro_list; p; p = p->next) { 3429 unsigned long diffs; 3430 3431 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; 3432 diffs |= p->vlan_tci ^ skb->vlan_tci; 3433 diffs |= compare_ether_header(skb_mac_header(p), 3434 skb_gro_mac_header(skb)); 3435 NAPI_GRO_CB(p)->same_flow = !diffs; 3436 NAPI_GRO_CB(p)->flush = 0; 3437 } 3438 3439 return dev_gro_receive(napi, skb); 3440 } 3441 3442 gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) 3443 { 3444 switch (ret) { 3445 case GRO_NORMAL: 3446 if (netif_receive_skb(skb)) 3447 ret = GRO_DROP; 3448 break; 3449 3450 case GRO_DROP: 3451 case GRO_MERGED_FREE: 3452 kfree_skb(skb); 3453 break; 3454 3455 case GRO_HELD: 3456 case GRO_MERGED: 3457 break; 3458 } 3459 3460 return ret; 3461 } 3462 EXPORT_SYMBOL(napi_skb_finish); 3463 3464 void skb_gro_reset_offset(struct sk_buff *skb) 3465 { 3466 NAPI_GRO_CB(skb)->data_offset = 0; 3467 NAPI_GRO_CB(skb)->frag0 = NULL; 3468 NAPI_GRO_CB(skb)->frag0_len = 0; 3469 3470 if (skb->mac_header == skb->tail && 3471 !PageHighMem(skb_shinfo(skb)->frags[0].page)) { 3472 NAPI_GRO_CB(skb)->frag0 = 3473 page_address(skb_shinfo(skb)->frags[0].page) + 3474 skb_shinfo(skb)->frags[0].page_offset; 3475 NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size; 3476 } 3477 } 3478 EXPORT_SYMBOL(skb_gro_reset_offset); 3479 3480 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3481 { 3482 skb_gro_reset_offset(skb); 3483 3484 return napi_skb_finish(__napi_gro_receive(napi, skb), skb); 3485 } 3486 EXPORT_SYMBOL(napi_gro_receive); 3487 3488 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) 3489 { 3490 __skb_pull(skb, skb_headlen(skb)); 3491 skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb)); 3492 skb->vlan_tci = 0; 3493 skb->dev = napi->dev; 3494 skb->skb_iif = 0; 3495 3496 napi->skb = skb; 3497 } 3498 3499 struct sk_buff *napi_get_frags(struct napi_struct *napi) 3500 { 3501 struct sk_buff *skb = napi->skb; 3502 3503 if (!skb) { 3504 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD); 3505 if (skb) 3506 napi->skb = skb; 3507 } 3508 return skb; 3509 } 3510 EXPORT_SYMBOL(napi_get_frags); 3511 3512 gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, 3513 gro_result_t ret) 3514 { 3515 switch (ret) { 3516 case GRO_NORMAL: 3517 case GRO_HELD: 3518 skb->protocol = eth_type_trans(skb, skb->dev); 3519 3520 if (ret == GRO_HELD) 3521 skb_gro_pull(skb, -ETH_HLEN); 3522 else if (netif_receive_skb(skb)) 3523 ret = GRO_DROP; 3524 break; 3525 3526 case GRO_DROP: 3527 case GRO_MERGED_FREE: 3528 napi_reuse_skb(napi, skb); 3529 break; 3530 3531 case GRO_MERGED: 3532 break; 3533 } 3534 3535 return ret; 3536 } 3537 EXPORT_SYMBOL(napi_frags_finish); 3538 3539 struct sk_buff *napi_frags_skb(struct napi_struct *napi) 3540 { 3541 struct sk_buff *skb = napi->skb; 3542 struct ethhdr *eth; 3543 unsigned int hlen; 3544 unsigned int off; 3545 3546 napi->skb = NULL; 3547 3548 skb_reset_mac_header(skb); 3549 skb_gro_reset_offset(skb); 3550 3551 off = skb_gro_offset(skb); 3552 hlen = off + sizeof(*eth); 3553 eth = skb_gro_header_fast(skb, off); 3554 if (skb_gro_header_hard(skb, hlen)) { 3555 eth = skb_gro_header_slow(skb, hlen, off); 3556 if (unlikely(!eth)) { 3557 napi_reuse_skb(napi, skb); 3558 skb = NULL; 3559 goto out; 3560 } 3561 } 3562 3563 skb_gro_pull(skb, sizeof(*eth)); 3564 3565 /* 3566 * This works because the only protocols we care about don't require 3567 * special handling. We'll fix it up properly at the end. 3568 */ 3569 skb->protocol = eth->h_proto; 3570 3571 out: 3572 return skb; 3573 } 3574 EXPORT_SYMBOL(napi_frags_skb); 3575 3576 gro_result_t napi_gro_frags(struct napi_struct *napi) 3577 { 3578 struct sk_buff *skb = napi_frags_skb(napi); 3579 3580 if (!skb) 3581 return GRO_DROP; 3582 3583 return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb)); 3584 } 3585 EXPORT_SYMBOL(napi_gro_frags); 3586 3587 /* 3588 * net_rps_action sends any pending IPI's for rps. 3589 * Note: called with local irq disabled, but exits with local irq enabled. 3590 */ 3591 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 3592 { 3593 #ifdef CONFIG_RPS 3594 struct softnet_data *remsd = sd->rps_ipi_list; 3595 3596 if (remsd) { 3597 sd->rps_ipi_list = NULL; 3598 3599 local_irq_enable(); 3600 3601 /* Send pending IPI's to kick RPS processing on remote cpus. */ 3602 while (remsd) { 3603 struct softnet_data *next = remsd->rps_ipi_next; 3604 3605 if (cpu_online(remsd->cpu)) 3606 __smp_call_function_single(remsd->cpu, 3607 &remsd->csd, 0); 3608 remsd = next; 3609 } 3610 } else 3611 #endif 3612 local_irq_enable(); 3613 } 3614 3615 static int process_backlog(struct napi_struct *napi, int quota) 3616 { 3617 int work = 0; 3618 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 3619 3620 #ifdef CONFIG_RPS 3621 /* Check if we have pending ipi, its better to send them now, 3622 * not waiting net_rx_action() end. 3623 */ 3624 if (sd->rps_ipi_list) { 3625 local_irq_disable(); 3626 net_rps_action_and_irq_enable(sd); 3627 } 3628 #endif 3629 napi->weight = weight_p; 3630 local_irq_disable(); 3631 while (work < quota) { 3632 struct sk_buff *skb; 3633 unsigned int qlen; 3634 3635 while ((skb = __skb_dequeue(&sd->process_queue))) { 3636 local_irq_enable(); 3637 __netif_receive_skb(skb); 3638 local_irq_disable(); 3639 input_queue_head_incr(sd); 3640 if (++work >= quota) { 3641 local_irq_enable(); 3642 return work; 3643 } 3644 } 3645 3646 rps_lock(sd); 3647 qlen = skb_queue_len(&sd->input_pkt_queue); 3648 if (qlen) 3649 skb_queue_splice_tail_init(&sd->input_pkt_queue, 3650 &sd->process_queue); 3651 3652 if (qlen < quota - work) { 3653 /* 3654 * Inline a custom version of __napi_complete(). 3655 * only current cpu owns and manipulates this napi, 3656 * and NAPI_STATE_SCHED is the only possible flag set on backlog. 3657 * we can use a plain write instead of clear_bit(), 3658 * and we dont need an smp_mb() memory barrier. 3659 */ 3660 list_del(&napi->poll_list); 3661 napi->state = 0; 3662 3663 quota = work + qlen; 3664 } 3665 rps_unlock(sd); 3666 } 3667 local_irq_enable(); 3668 3669 return work; 3670 } 3671 3672 /** 3673 * __napi_schedule - schedule for receive 3674 * @n: entry to schedule 3675 * 3676 * The entry's receive function will be scheduled to run 3677 */ 3678 void __napi_schedule(struct napi_struct *n) 3679 { 3680 unsigned long flags; 3681 3682 local_irq_save(flags); 3683 ____napi_schedule(&__get_cpu_var(softnet_data), n); 3684 local_irq_restore(flags); 3685 } 3686 EXPORT_SYMBOL(__napi_schedule); 3687 3688 void __napi_complete(struct napi_struct *n) 3689 { 3690 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); 3691 BUG_ON(n->gro_list); 3692 3693 list_del(&n->poll_list); 3694 smp_mb__before_clear_bit(); 3695 clear_bit(NAPI_STATE_SCHED, &n->state); 3696 } 3697 EXPORT_SYMBOL(__napi_complete); 3698 3699 void napi_complete(struct napi_struct *n) 3700 { 3701 unsigned long flags; 3702 3703 /* 3704 * don't let napi dequeue from the cpu poll list 3705 * just in case its running on a different cpu 3706 */ 3707 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state))) 3708 return; 3709 3710 napi_gro_flush(n); 3711 local_irq_save(flags); 3712 __napi_complete(n); 3713 local_irq_restore(flags); 3714 } 3715 EXPORT_SYMBOL(napi_complete); 3716 3717 void netif_napi_add(struct net_device *dev, struct napi_struct *napi, 3718 int (*poll)(struct napi_struct *, int), int weight) 3719 { 3720 INIT_LIST_HEAD(&napi->poll_list); 3721 napi->gro_count = 0; 3722 napi->gro_list = NULL; 3723 napi->skb = NULL; 3724 napi->poll = poll; 3725 napi->weight = weight; 3726 list_add(&napi->dev_list, &dev->napi_list); 3727 napi->dev = dev; 3728 #ifdef CONFIG_NETPOLL 3729 spin_lock_init(&napi->poll_lock); 3730 napi->poll_owner = -1; 3731 #endif 3732 set_bit(NAPI_STATE_SCHED, &napi->state); 3733 } 3734 EXPORT_SYMBOL(netif_napi_add); 3735 3736 void netif_napi_del(struct napi_struct *napi) 3737 { 3738 struct sk_buff *skb, *next; 3739 3740 list_del_init(&napi->dev_list); 3741 napi_free_frags(napi); 3742 3743 for (skb = napi->gro_list; skb; skb = next) { 3744 next = skb->next; 3745 skb->next = NULL; 3746 kfree_skb(skb); 3747 } 3748 3749 napi->gro_list = NULL; 3750 napi->gro_count = 0; 3751 } 3752 EXPORT_SYMBOL(netif_napi_del); 3753 3754 static void net_rx_action(struct softirq_action *h) 3755 { 3756 struct softnet_data *sd = &__get_cpu_var(softnet_data); 3757 unsigned long time_limit = jiffies + 2; 3758 int budget = netdev_budget; 3759 void *have; 3760 3761 local_irq_disable(); 3762 3763 while (!list_empty(&sd->poll_list)) { 3764 struct napi_struct *n; 3765 int work, weight; 3766 3767 /* If softirq window is exhuasted then punt. 3768 * Allow this to run for 2 jiffies since which will allow 3769 * an average latency of 1.5/HZ. 3770 */ 3771 if (unlikely(budget <= 0 || time_after(jiffies, time_limit))) 3772 goto softnet_break; 3773 3774 local_irq_enable(); 3775 3776 /* Even though interrupts have been re-enabled, this 3777 * access is safe because interrupts can only add new 3778 * entries to the tail of this list, and only ->poll() 3779 * calls can remove this head entry from the list. 3780 */ 3781 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list); 3782 3783 have = netpoll_poll_lock(n); 3784 3785 weight = n->weight; 3786 3787 /* This NAPI_STATE_SCHED test is for avoiding a race 3788 * with netpoll's poll_napi(). Only the entity which 3789 * obtains the lock and sees NAPI_STATE_SCHED set will 3790 * actually make the ->poll() call. Therefore we avoid 3791 * accidentally calling ->poll() when NAPI is not scheduled. 3792 */ 3793 work = 0; 3794 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 3795 work = n->poll(n, weight); 3796 trace_napi_poll(n); 3797 } 3798 3799 WARN_ON_ONCE(work > weight); 3800 3801 budget -= work; 3802 3803 local_irq_disable(); 3804 3805 /* Drivers must not modify the NAPI state if they 3806 * consume the entire weight. In such cases this code 3807 * still "owns" the NAPI instance and therefore can 3808 * move the instance around on the list at-will. 3809 */ 3810 if (unlikely(work == weight)) { 3811 if (unlikely(napi_disable_pending(n))) { 3812 local_irq_enable(); 3813 napi_complete(n); 3814 local_irq_disable(); 3815 } else 3816 list_move_tail(&n->poll_list, &sd->poll_list); 3817 } 3818 3819 netpoll_poll_unlock(have); 3820 } 3821 out: 3822 net_rps_action_and_irq_enable(sd); 3823 3824 #ifdef CONFIG_NET_DMA 3825 /* 3826 * There may not be any more sk_buffs coming right now, so push 3827 * any pending DMA copies to hardware 3828 */ 3829 dma_issue_pending_all(); 3830 #endif 3831 3832 return; 3833 3834 softnet_break: 3835 sd->time_squeeze++; 3836 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 3837 goto out; 3838 } 3839 3840 static gifconf_func_t *gifconf_list[NPROTO]; 3841 3842 /** 3843 * register_gifconf - register a SIOCGIF handler 3844 * @family: Address family 3845 * @gifconf: Function handler 3846 * 3847 * Register protocol dependent address dumping routines. The handler 3848 * that is passed must not be freed or reused until it has been replaced 3849 * by another handler. 3850 */ 3851 int register_gifconf(unsigned int family, gifconf_func_t *gifconf) 3852 { 3853 if (family >= NPROTO) 3854 return -EINVAL; 3855 gifconf_list[family] = gifconf; 3856 return 0; 3857 } 3858 EXPORT_SYMBOL(register_gifconf); 3859 3860 3861 /* 3862 * Map an interface index to its name (SIOCGIFNAME) 3863 */ 3864 3865 /* 3866 * We need this ioctl for efficient implementation of the 3867 * if_indextoname() function required by the IPv6 API. Without 3868 * it, we would have to search all the interfaces to find a 3869 * match. --pb 3870 */ 3871 3872 static int dev_ifname(struct net *net, struct ifreq __user *arg) 3873 { 3874 struct net_device *dev; 3875 struct ifreq ifr; 3876 3877 /* 3878 * Fetch the caller's info block. 3879 */ 3880 3881 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 3882 return -EFAULT; 3883 3884 rcu_read_lock(); 3885 dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex); 3886 if (!dev) { 3887 rcu_read_unlock(); 3888 return -ENODEV; 3889 } 3890 3891 strcpy(ifr.ifr_name, dev->name); 3892 rcu_read_unlock(); 3893 3894 if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) 3895 return -EFAULT; 3896 return 0; 3897 } 3898 3899 /* 3900 * Perform a SIOCGIFCONF call. This structure will change 3901 * size eventually, and there is nothing I can do about it. 3902 * Thus we will need a 'compatibility mode'. 3903 */ 3904 3905 static int dev_ifconf(struct net *net, char __user *arg) 3906 { 3907 struct ifconf ifc; 3908 struct net_device *dev; 3909 char __user *pos; 3910 int len; 3911 int total; 3912 int i; 3913 3914 /* 3915 * Fetch the caller's info block. 3916 */ 3917 3918 if (copy_from_user(&ifc, arg, sizeof(struct ifconf))) 3919 return -EFAULT; 3920 3921 pos = ifc.ifc_buf; 3922 len = ifc.ifc_len; 3923 3924 /* 3925 * Loop over the interfaces, and write an info block for each. 3926 */ 3927 3928 total = 0; 3929 for_each_netdev(net, dev) { 3930 for (i = 0; i < NPROTO; i++) { 3931 if (gifconf_list[i]) { 3932 int done; 3933 if (!pos) 3934 done = gifconf_list[i](dev, NULL, 0); 3935 else 3936 done = gifconf_list[i](dev, pos + total, 3937 len - total); 3938 if (done < 0) 3939 return -EFAULT; 3940 total += done; 3941 } 3942 } 3943 } 3944 3945 /* 3946 * All done. Write the updated control block back to the caller. 3947 */ 3948 ifc.ifc_len = total; 3949 3950 /* 3951 * Both BSD and Solaris return 0 here, so we do too. 3952 */ 3953 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0; 3954 } 3955 3956 #ifdef CONFIG_PROC_FS 3957 /* 3958 * This is invoked by the /proc filesystem handler to display a device 3959 * in detail. 3960 */ 3961 void *dev_seq_start(struct seq_file *seq, loff_t *pos) 3962 __acquires(RCU) 3963 { 3964 struct net *net = seq_file_net(seq); 3965 loff_t off; 3966 struct net_device *dev; 3967 3968 rcu_read_lock(); 3969 if (!*pos) 3970 return SEQ_START_TOKEN; 3971 3972 off = 1; 3973 for_each_netdev_rcu(net, dev) 3974 if (off++ == *pos) 3975 return dev; 3976 3977 return NULL; 3978 } 3979 3980 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3981 { 3982 struct net_device *dev = v; 3983 3984 if (v == SEQ_START_TOKEN) 3985 dev = first_net_device_rcu(seq_file_net(seq)); 3986 else 3987 dev = next_net_device_rcu(dev); 3988 3989 ++*pos; 3990 return dev; 3991 } 3992 3993 void dev_seq_stop(struct seq_file *seq, void *v) 3994 __releases(RCU) 3995 { 3996 rcu_read_unlock(); 3997 } 3998 3999 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev) 4000 { 4001 struct rtnl_link_stats64 temp; 4002 const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp); 4003 4004 seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu " 4005 "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n", 4006 dev->name, stats->rx_bytes, stats->rx_packets, 4007 stats->rx_errors, 4008 stats->rx_dropped + stats->rx_missed_errors, 4009 stats->rx_fifo_errors, 4010 stats->rx_length_errors + stats->rx_over_errors + 4011 stats->rx_crc_errors + stats->rx_frame_errors, 4012 stats->rx_compressed, stats->multicast, 4013 stats->tx_bytes, stats->tx_packets, 4014 stats->tx_errors, stats->tx_dropped, 4015 stats->tx_fifo_errors, stats->collisions, 4016 stats->tx_carrier_errors + 4017 stats->tx_aborted_errors + 4018 stats->tx_window_errors + 4019 stats->tx_heartbeat_errors, 4020 stats->tx_compressed); 4021 } 4022 4023 /* 4024 * Called from the PROCfs module. This now uses the new arbitrary sized 4025 * /proc/net interface to create /proc/net/dev 4026 */ 4027 static int dev_seq_show(struct seq_file *seq, void *v) 4028 { 4029 if (v == SEQ_START_TOKEN) 4030 seq_puts(seq, "Inter-| Receive " 4031 " | Transmit\n" 4032 " face |bytes packets errs drop fifo frame " 4033 "compressed multicast|bytes packets errs " 4034 "drop fifo colls carrier compressed\n"); 4035 else 4036 dev_seq_printf_stats(seq, v); 4037 return 0; 4038 } 4039 4040 static struct softnet_data *softnet_get_online(loff_t *pos) 4041 { 4042 struct softnet_data *sd = NULL; 4043 4044 while (*pos < nr_cpu_ids) 4045 if (cpu_online(*pos)) { 4046 sd = &per_cpu(softnet_data, *pos); 4047 break; 4048 } else 4049 ++*pos; 4050 return sd; 4051 } 4052 4053 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) 4054 { 4055 return softnet_get_online(pos); 4056 } 4057 4058 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4059 { 4060 ++*pos; 4061 return softnet_get_online(pos); 4062 } 4063 4064 static void softnet_seq_stop(struct seq_file *seq, void *v) 4065 { 4066 } 4067 4068 static int softnet_seq_show(struct seq_file *seq, void *v) 4069 { 4070 struct softnet_data *sd = v; 4071 4072 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 4073 sd->processed, sd->dropped, sd->time_squeeze, 0, 4074 0, 0, 0, 0, /* was fastroute */ 4075 sd->cpu_collision, sd->received_rps); 4076 return 0; 4077 } 4078 4079 static const struct seq_operations dev_seq_ops = { 4080 .start = dev_seq_start, 4081 .next = dev_seq_next, 4082 .stop = dev_seq_stop, 4083 .show = dev_seq_show, 4084 }; 4085 4086 static int dev_seq_open(struct inode *inode, struct file *file) 4087 { 4088 return seq_open_net(inode, file, &dev_seq_ops, 4089 sizeof(struct seq_net_private)); 4090 } 4091 4092 static const struct file_operations dev_seq_fops = { 4093 .owner = THIS_MODULE, 4094 .open = dev_seq_open, 4095 .read = seq_read, 4096 .llseek = seq_lseek, 4097 .release = seq_release_net, 4098 }; 4099 4100 static const struct seq_operations softnet_seq_ops = { 4101 .start = softnet_seq_start, 4102 .next = softnet_seq_next, 4103 .stop = softnet_seq_stop, 4104 .show = softnet_seq_show, 4105 }; 4106 4107 static int softnet_seq_open(struct inode *inode, struct file *file) 4108 { 4109 return seq_open(file, &softnet_seq_ops); 4110 } 4111 4112 static const struct file_operations softnet_seq_fops = { 4113 .owner = THIS_MODULE, 4114 .open = softnet_seq_open, 4115 .read = seq_read, 4116 .llseek = seq_lseek, 4117 .release = seq_release, 4118 }; 4119 4120 static void *ptype_get_idx(loff_t pos) 4121 { 4122 struct packet_type *pt = NULL; 4123 loff_t i = 0; 4124 int t; 4125 4126 list_for_each_entry_rcu(pt, &ptype_all, list) { 4127 if (i == pos) 4128 return pt; 4129 ++i; 4130 } 4131 4132 for (t = 0; t < PTYPE_HASH_SIZE; t++) { 4133 list_for_each_entry_rcu(pt, &ptype_base[t], list) { 4134 if (i == pos) 4135 return pt; 4136 ++i; 4137 } 4138 } 4139 return NULL; 4140 } 4141 4142 static void *ptype_seq_start(struct seq_file *seq, loff_t *pos) 4143 __acquires(RCU) 4144 { 4145 rcu_read_lock(); 4146 return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN; 4147 } 4148 4149 static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4150 { 4151 struct packet_type *pt; 4152 struct list_head *nxt; 4153 int hash; 4154 4155 ++*pos; 4156 if (v == SEQ_START_TOKEN) 4157 return ptype_get_idx(0); 4158 4159 pt = v; 4160 nxt = pt->list.next; 4161 if (pt->type == htons(ETH_P_ALL)) { 4162 if (nxt != &ptype_all) 4163 goto found; 4164 hash = 0; 4165 nxt = ptype_base[0].next; 4166 } else 4167 hash = ntohs(pt->type) & PTYPE_HASH_MASK; 4168 4169 while (nxt == &ptype_base[hash]) { 4170 if (++hash >= PTYPE_HASH_SIZE) 4171 return NULL; 4172 nxt = ptype_base[hash].next; 4173 } 4174 found: 4175 return list_entry(nxt, struct packet_type, list); 4176 } 4177 4178 static void ptype_seq_stop(struct seq_file *seq, void *v) 4179 __releases(RCU) 4180 { 4181 rcu_read_unlock(); 4182 } 4183 4184 static int ptype_seq_show(struct seq_file *seq, void *v) 4185 { 4186 struct packet_type *pt = v; 4187 4188 if (v == SEQ_START_TOKEN) 4189 seq_puts(seq, "Type Device Function\n"); 4190 else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) { 4191 if (pt->type == htons(ETH_P_ALL)) 4192 seq_puts(seq, "ALL "); 4193 else 4194 seq_printf(seq, "%04x", ntohs(pt->type)); 4195 4196 seq_printf(seq, " %-8s %pF\n", 4197 pt->dev ? pt->dev->name : "", pt->func); 4198 } 4199 4200 return 0; 4201 } 4202 4203 static const struct seq_operations ptype_seq_ops = { 4204 .start = ptype_seq_start, 4205 .next = ptype_seq_next, 4206 .stop = ptype_seq_stop, 4207 .show = ptype_seq_show, 4208 }; 4209 4210 static int ptype_seq_open(struct inode *inode, struct file *file) 4211 { 4212 return seq_open_net(inode, file, &ptype_seq_ops, 4213 sizeof(struct seq_net_private)); 4214 } 4215 4216 static const struct file_operations ptype_seq_fops = { 4217 .owner = THIS_MODULE, 4218 .open = ptype_seq_open, 4219 .read = seq_read, 4220 .llseek = seq_lseek, 4221 .release = seq_release_net, 4222 }; 4223 4224 4225 static int __net_init dev_proc_net_init(struct net *net) 4226 { 4227 int rc = -ENOMEM; 4228 4229 if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops)) 4230 goto out; 4231 if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops)) 4232 goto out_dev; 4233 if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops)) 4234 goto out_softnet; 4235 4236 if (wext_proc_init(net)) 4237 goto out_ptype; 4238 rc = 0; 4239 out: 4240 return rc; 4241 out_ptype: 4242 proc_net_remove(net, "ptype"); 4243 out_softnet: 4244 proc_net_remove(net, "softnet_stat"); 4245 out_dev: 4246 proc_net_remove(net, "dev"); 4247 goto out; 4248 } 4249 4250 static void __net_exit dev_proc_net_exit(struct net *net) 4251 { 4252 wext_proc_exit(net); 4253 4254 proc_net_remove(net, "ptype"); 4255 proc_net_remove(net, "softnet_stat"); 4256 proc_net_remove(net, "dev"); 4257 } 4258 4259 static struct pernet_operations __net_initdata dev_proc_ops = { 4260 .init = dev_proc_net_init, 4261 .exit = dev_proc_net_exit, 4262 }; 4263 4264 static int __init dev_proc_init(void) 4265 { 4266 return register_pernet_subsys(&dev_proc_ops); 4267 } 4268 #else 4269 #define dev_proc_init() 0 4270 #endif /* CONFIG_PROC_FS */ 4271 4272 4273 /** 4274 * netdev_set_master - set up master pointer 4275 * @slave: slave device 4276 * @master: new master device 4277 * 4278 * Changes the master device of the slave. Pass %NULL to break the 4279 * bonding. The caller must hold the RTNL semaphore. On a failure 4280 * a negative errno code is returned. On success the reference counts 4281 * are adjusted and the function returns zero. 4282 */ 4283 int netdev_set_master(struct net_device *slave, struct net_device *master) 4284 { 4285 struct net_device *old = slave->master; 4286 4287 ASSERT_RTNL(); 4288 4289 if (master) { 4290 if (old) 4291 return -EBUSY; 4292 dev_hold(master); 4293 } 4294 4295 slave->master = master; 4296 4297 if (old) { 4298 synchronize_net(); 4299 dev_put(old); 4300 } 4301 return 0; 4302 } 4303 EXPORT_SYMBOL(netdev_set_master); 4304 4305 /** 4306 * netdev_set_bond_master - set up bonding master/slave pair 4307 * @slave: slave device 4308 * @master: new master device 4309 * 4310 * Changes the master device of the slave. Pass %NULL to break the 4311 * bonding. The caller must hold the RTNL semaphore. On a failure 4312 * a negative errno code is returned. On success %RTM_NEWLINK is sent 4313 * to the routing socket and the function returns zero. 4314 */ 4315 int netdev_set_bond_master(struct net_device *slave, struct net_device *master) 4316 { 4317 int err; 4318 4319 ASSERT_RTNL(); 4320 4321 err = netdev_set_master(slave, master); 4322 if (err) 4323 return err; 4324 if (master) 4325 slave->flags |= IFF_SLAVE; 4326 else 4327 slave->flags &= ~IFF_SLAVE; 4328 4329 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE); 4330 return 0; 4331 } 4332 EXPORT_SYMBOL(netdev_set_bond_master); 4333 4334 static void dev_change_rx_flags(struct net_device *dev, int flags) 4335 { 4336 const struct net_device_ops *ops = dev->netdev_ops; 4337 4338 if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags) 4339 ops->ndo_change_rx_flags(dev, flags); 4340 } 4341 4342 static int __dev_set_promiscuity(struct net_device *dev, int inc) 4343 { 4344 unsigned short old_flags = dev->flags; 4345 uid_t uid; 4346 gid_t gid; 4347 4348 ASSERT_RTNL(); 4349 4350 dev->flags |= IFF_PROMISC; 4351 dev->promiscuity += inc; 4352 if (dev->promiscuity == 0) { 4353 /* 4354 * Avoid overflow. 4355 * If inc causes overflow, untouch promisc and return error. 4356 */ 4357 if (inc < 0) 4358 dev->flags &= ~IFF_PROMISC; 4359 else { 4360 dev->promiscuity -= inc; 4361 printk(KERN_WARNING "%s: promiscuity touches roof, " 4362 "set promiscuity failed, promiscuity feature " 4363 "of device might be broken.\n", dev->name); 4364 return -EOVERFLOW; 4365 } 4366 } 4367 if (dev->flags != old_flags) { 4368 printk(KERN_INFO "device %s %s promiscuous mode\n", 4369 dev->name, (dev->flags & IFF_PROMISC) ? "entered" : 4370 "left"); 4371 if (audit_enabled) { 4372 current_uid_gid(&uid, &gid); 4373 audit_log(current->audit_context, GFP_ATOMIC, 4374 AUDIT_ANOM_PROMISCUOUS, 4375 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 4376 dev->name, (dev->flags & IFF_PROMISC), 4377 (old_flags & IFF_PROMISC), 4378 audit_get_loginuid(current), 4379 uid, gid, 4380 audit_get_sessionid(current)); 4381 } 4382 4383 dev_change_rx_flags(dev, IFF_PROMISC); 4384 } 4385 return 0; 4386 } 4387 4388 /** 4389 * dev_set_promiscuity - update promiscuity count on a device 4390 * @dev: device 4391 * @inc: modifier 4392 * 4393 * Add or remove promiscuity from a device. While the count in the device 4394 * remains above zero the interface remains promiscuous. Once it hits zero 4395 * the device reverts back to normal filtering operation. A negative inc 4396 * value is used to drop promiscuity on the device. 4397 * Return 0 if successful or a negative errno code on error. 4398 */ 4399 int dev_set_promiscuity(struct net_device *dev, int inc) 4400 { 4401 unsigned short old_flags = dev->flags; 4402 int err; 4403 4404 err = __dev_set_promiscuity(dev, inc); 4405 if (err < 0) 4406 return err; 4407 if (dev->flags != old_flags) 4408 dev_set_rx_mode(dev); 4409 return err; 4410 } 4411 EXPORT_SYMBOL(dev_set_promiscuity); 4412 4413 /** 4414 * dev_set_allmulti - update allmulti count on a device 4415 * @dev: device 4416 * @inc: modifier 4417 * 4418 * Add or remove reception of all multicast frames to a device. While the 4419 * count in the device remains above zero the interface remains listening 4420 * to all interfaces. Once it hits zero the device reverts back to normal 4421 * filtering operation. A negative @inc value is used to drop the counter 4422 * when releasing a resource needing all multicasts. 4423 * Return 0 if successful or a negative errno code on error. 4424 */ 4425 4426 int dev_set_allmulti(struct net_device *dev, int inc) 4427 { 4428 unsigned short old_flags = dev->flags; 4429 4430 ASSERT_RTNL(); 4431 4432 dev->flags |= IFF_ALLMULTI; 4433 dev->allmulti += inc; 4434 if (dev->allmulti == 0) { 4435 /* 4436 * Avoid overflow. 4437 * If inc causes overflow, untouch allmulti and return error. 4438 */ 4439 if (inc < 0) 4440 dev->flags &= ~IFF_ALLMULTI; 4441 else { 4442 dev->allmulti -= inc; 4443 printk(KERN_WARNING "%s: allmulti touches roof, " 4444 "set allmulti failed, allmulti feature of " 4445 "device might be broken.\n", dev->name); 4446 return -EOVERFLOW; 4447 } 4448 } 4449 if (dev->flags ^ old_flags) { 4450 dev_change_rx_flags(dev, IFF_ALLMULTI); 4451 dev_set_rx_mode(dev); 4452 } 4453 return 0; 4454 } 4455 EXPORT_SYMBOL(dev_set_allmulti); 4456 4457 /* 4458 * Upload unicast and multicast address lists to device and 4459 * configure RX filtering. When the device doesn't support unicast 4460 * filtering it is put in promiscuous mode while unicast addresses 4461 * are present. 4462 */ 4463 void __dev_set_rx_mode(struct net_device *dev) 4464 { 4465 const struct net_device_ops *ops = dev->netdev_ops; 4466 4467 /* dev_open will call this function so the list will stay sane. */ 4468 if (!(dev->flags&IFF_UP)) 4469 return; 4470 4471 if (!netif_device_present(dev)) 4472 return; 4473 4474 if (ops->ndo_set_rx_mode) 4475 ops->ndo_set_rx_mode(dev); 4476 else { 4477 /* Unicast addresses changes may only happen under the rtnl, 4478 * therefore calling __dev_set_promiscuity here is safe. 4479 */ 4480 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 4481 __dev_set_promiscuity(dev, 1); 4482 dev->uc_promisc = 1; 4483 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 4484 __dev_set_promiscuity(dev, -1); 4485 dev->uc_promisc = 0; 4486 } 4487 4488 if (ops->ndo_set_multicast_list) 4489 ops->ndo_set_multicast_list(dev); 4490 } 4491 } 4492 4493 void dev_set_rx_mode(struct net_device *dev) 4494 { 4495 netif_addr_lock_bh(dev); 4496 __dev_set_rx_mode(dev); 4497 netif_addr_unlock_bh(dev); 4498 } 4499 4500 /** 4501 * dev_ethtool_get_settings - call device's ethtool_ops::get_settings() 4502 * @dev: device 4503 * @cmd: memory area for ethtool_ops::get_settings() result 4504 * 4505 * The cmd arg is initialized properly (cleared and 4506 * ethtool_cmd::cmd field set to ETHTOOL_GSET). 4507 * 4508 * Return device's ethtool_ops::get_settings() result value or 4509 * -EOPNOTSUPP when device doesn't expose 4510 * ethtool_ops::get_settings() operation. 4511 */ 4512 int dev_ethtool_get_settings(struct net_device *dev, 4513 struct ethtool_cmd *cmd) 4514 { 4515 if (!dev->ethtool_ops || !dev->ethtool_ops->get_settings) 4516 return -EOPNOTSUPP; 4517 4518 memset(cmd, 0, sizeof(struct ethtool_cmd)); 4519 cmd->cmd = ETHTOOL_GSET; 4520 return dev->ethtool_ops->get_settings(dev, cmd); 4521 } 4522 EXPORT_SYMBOL(dev_ethtool_get_settings); 4523 4524 /** 4525 * dev_get_flags - get flags reported to userspace 4526 * @dev: device 4527 * 4528 * Get the combination of flag bits exported through APIs to userspace. 4529 */ 4530 unsigned dev_get_flags(const struct net_device *dev) 4531 { 4532 unsigned flags; 4533 4534 flags = (dev->flags & ~(IFF_PROMISC | 4535 IFF_ALLMULTI | 4536 IFF_RUNNING | 4537 IFF_LOWER_UP | 4538 IFF_DORMANT)) | 4539 (dev->gflags & (IFF_PROMISC | 4540 IFF_ALLMULTI)); 4541 4542 if (netif_running(dev)) { 4543 if (netif_oper_up(dev)) 4544 flags |= IFF_RUNNING; 4545 if (netif_carrier_ok(dev)) 4546 flags |= IFF_LOWER_UP; 4547 if (netif_dormant(dev)) 4548 flags |= IFF_DORMANT; 4549 } 4550 4551 return flags; 4552 } 4553 EXPORT_SYMBOL(dev_get_flags); 4554 4555 int __dev_change_flags(struct net_device *dev, unsigned int flags) 4556 { 4557 int old_flags = dev->flags; 4558 int ret; 4559 4560 ASSERT_RTNL(); 4561 4562 /* 4563 * Set the flags on our device. 4564 */ 4565 4566 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 4567 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 4568 IFF_AUTOMEDIA)) | 4569 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 4570 IFF_ALLMULTI)); 4571 4572 /* 4573 * Load in the correct multicast list now the flags have changed. 4574 */ 4575 4576 if ((old_flags ^ flags) & IFF_MULTICAST) 4577 dev_change_rx_flags(dev, IFF_MULTICAST); 4578 4579 dev_set_rx_mode(dev); 4580 4581 /* 4582 * Have we downed the interface. We handle IFF_UP ourselves 4583 * according to user attempts to set it, rather than blindly 4584 * setting it. 4585 */ 4586 4587 ret = 0; 4588 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ 4589 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev); 4590 4591 if (!ret) 4592 dev_set_rx_mode(dev); 4593 } 4594 4595 if ((flags ^ dev->gflags) & IFF_PROMISC) { 4596 int inc = (flags & IFF_PROMISC) ? 1 : -1; 4597 4598 dev->gflags ^= IFF_PROMISC; 4599 dev_set_promiscuity(dev, inc); 4600 } 4601 4602 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 4603 is important. Some (broken) drivers set IFF_PROMISC, when 4604 IFF_ALLMULTI is requested not asking us and not reporting. 4605 */ 4606 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 4607 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 4608 4609 dev->gflags ^= IFF_ALLMULTI; 4610 dev_set_allmulti(dev, inc); 4611 } 4612 4613 return ret; 4614 } 4615 4616 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags) 4617 { 4618 unsigned int changes = dev->flags ^ old_flags; 4619 4620 if (changes & IFF_UP) { 4621 if (dev->flags & IFF_UP) 4622 call_netdevice_notifiers(NETDEV_UP, dev); 4623 else 4624 call_netdevice_notifiers(NETDEV_DOWN, dev); 4625 } 4626 4627 if (dev->flags & IFF_UP && 4628 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) 4629 call_netdevice_notifiers(NETDEV_CHANGE, dev); 4630 } 4631 4632 /** 4633 * dev_change_flags - change device settings 4634 * @dev: device 4635 * @flags: device state flags 4636 * 4637 * Change settings on device based state flags. The flags are 4638 * in the userspace exported format. 4639 */ 4640 int dev_change_flags(struct net_device *dev, unsigned flags) 4641 { 4642 int ret, changes; 4643 int old_flags = dev->flags; 4644 4645 ret = __dev_change_flags(dev, flags); 4646 if (ret < 0) 4647 return ret; 4648 4649 changes = old_flags ^ dev->flags; 4650 if (changes) 4651 rtmsg_ifinfo(RTM_NEWLINK, dev, changes); 4652 4653 __dev_notify_flags(dev, old_flags); 4654 return ret; 4655 } 4656 EXPORT_SYMBOL(dev_change_flags); 4657 4658 /** 4659 * dev_set_mtu - Change maximum transfer unit 4660 * @dev: device 4661 * @new_mtu: new transfer unit 4662 * 4663 * Change the maximum transfer size of the network device. 4664 */ 4665 int dev_set_mtu(struct net_device *dev, int new_mtu) 4666 { 4667 const struct net_device_ops *ops = dev->netdev_ops; 4668 int err; 4669 4670 if (new_mtu == dev->mtu) 4671 return 0; 4672 4673 /* MTU must be positive. */ 4674 if (new_mtu < 0) 4675 return -EINVAL; 4676 4677 if (!netif_device_present(dev)) 4678 return -ENODEV; 4679 4680 err = 0; 4681 if (ops->ndo_change_mtu) 4682 err = ops->ndo_change_mtu(dev, new_mtu); 4683 else 4684 dev->mtu = new_mtu; 4685 4686 if (!err && dev->flags & IFF_UP) 4687 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); 4688 return err; 4689 } 4690 EXPORT_SYMBOL(dev_set_mtu); 4691 4692 /** 4693 * dev_set_group - Change group this device belongs to 4694 * @dev: device 4695 * @new_group: group this device should belong to 4696 */ 4697 void dev_set_group(struct net_device *dev, int new_group) 4698 { 4699 dev->group = new_group; 4700 } 4701 EXPORT_SYMBOL(dev_set_group); 4702 4703 /** 4704 * dev_set_mac_address - Change Media Access Control Address 4705 * @dev: device 4706 * @sa: new address 4707 * 4708 * Change the hardware (MAC) address of the device 4709 */ 4710 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) 4711 { 4712 const struct net_device_ops *ops = dev->netdev_ops; 4713 int err; 4714 4715 if (!ops->ndo_set_mac_address) 4716 return -EOPNOTSUPP; 4717 if (sa->sa_family != dev->type) 4718 return -EINVAL; 4719 if (!netif_device_present(dev)) 4720 return -ENODEV; 4721 err = ops->ndo_set_mac_address(dev, sa); 4722 if (!err) 4723 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4724 return err; 4725 } 4726 EXPORT_SYMBOL(dev_set_mac_address); 4727 4728 /* 4729 * Perform the SIOCxIFxxx calls, inside rcu_read_lock() 4730 */ 4731 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd) 4732 { 4733 int err; 4734 struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name); 4735 4736 if (!dev) 4737 return -ENODEV; 4738 4739 switch (cmd) { 4740 case SIOCGIFFLAGS: /* Get interface flags */ 4741 ifr->ifr_flags = (short) dev_get_flags(dev); 4742 return 0; 4743 4744 case SIOCGIFMETRIC: /* Get the metric on the interface 4745 (currently unused) */ 4746 ifr->ifr_metric = 0; 4747 return 0; 4748 4749 case SIOCGIFMTU: /* Get the MTU of a device */ 4750 ifr->ifr_mtu = dev->mtu; 4751 return 0; 4752 4753 case SIOCGIFHWADDR: 4754 if (!dev->addr_len) 4755 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data); 4756 else 4757 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr, 4758 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4759 ifr->ifr_hwaddr.sa_family = dev->type; 4760 return 0; 4761 4762 case SIOCGIFSLAVE: 4763 err = -EINVAL; 4764 break; 4765 4766 case SIOCGIFMAP: 4767 ifr->ifr_map.mem_start = dev->mem_start; 4768 ifr->ifr_map.mem_end = dev->mem_end; 4769 ifr->ifr_map.base_addr = dev->base_addr; 4770 ifr->ifr_map.irq = dev->irq; 4771 ifr->ifr_map.dma = dev->dma; 4772 ifr->ifr_map.port = dev->if_port; 4773 return 0; 4774 4775 case SIOCGIFINDEX: 4776 ifr->ifr_ifindex = dev->ifindex; 4777 return 0; 4778 4779 case SIOCGIFTXQLEN: 4780 ifr->ifr_qlen = dev->tx_queue_len; 4781 return 0; 4782 4783 default: 4784 /* dev_ioctl() should ensure this case 4785 * is never reached 4786 */ 4787 WARN_ON(1); 4788 err = -ENOTTY; 4789 break; 4790 4791 } 4792 return err; 4793 } 4794 4795 /* 4796 * Perform the SIOCxIFxxx calls, inside rtnl_lock() 4797 */ 4798 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd) 4799 { 4800 int err; 4801 struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name); 4802 const struct net_device_ops *ops; 4803 4804 if (!dev) 4805 return -ENODEV; 4806 4807 ops = dev->netdev_ops; 4808 4809 switch (cmd) { 4810 case SIOCSIFFLAGS: /* Set interface flags */ 4811 return dev_change_flags(dev, ifr->ifr_flags); 4812 4813 case SIOCSIFMETRIC: /* Set the metric on the interface 4814 (currently unused) */ 4815 return -EOPNOTSUPP; 4816 4817 case SIOCSIFMTU: /* Set the MTU of a device */ 4818 return dev_set_mtu(dev, ifr->ifr_mtu); 4819 4820 case SIOCSIFHWADDR: 4821 return dev_set_mac_address(dev, &ifr->ifr_hwaddr); 4822 4823 case SIOCSIFHWBROADCAST: 4824 if (ifr->ifr_hwaddr.sa_family != dev->type) 4825 return -EINVAL; 4826 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data, 4827 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4828 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4829 return 0; 4830 4831 case SIOCSIFMAP: 4832 if (ops->ndo_set_config) { 4833 if (!netif_device_present(dev)) 4834 return -ENODEV; 4835 return ops->ndo_set_config(dev, &ifr->ifr_map); 4836 } 4837 return -EOPNOTSUPP; 4838 4839 case SIOCADDMULTI: 4840 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4841 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4842 return -EINVAL; 4843 if (!netif_device_present(dev)) 4844 return -ENODEV; 4845 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data); 4846 4847 case SIOCDELMULTI: 4848 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4849 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4850 return -EINVAL; 4851 if (!netif_device_present(dev)) 4852 return -ENODEV; 4853 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data); 4854 4855 case SIOCSIFTXQLEN: 4856 if (ifr->ifr_qlen < 0) 4857 return -EINVAL; 4858 dev->tx_queue_len = ifr->ifr_qlen; 4859 return 0; 4860 4861 case SIOCSIFNAME: 4862 ifr->ifr_newname[IFNAMSIZ-1] = '\0'; 4863 return dev_change_name(dev, ifr->ifr_newname); 4864 4865 /* 4866 * Unknown or private ioctl 4867 */ 4868 default: 4869 if ((cmd >= SIOCDEVPRIVATE && 4870 cmd <= SIOCDEVPRIVATE + 15) || 4871 cmd == SIOCBONDENSLAVE || 4872 cmd == SIOCBONDRELEASE || 4873 cmd == SIOCBONDSETHWADDR || 4874 cmd == SIOCBONDSLAVEINFOQUERY || 4875 cmd == SIOCBONDINFOQUERY || 4876 cmd == SIOCBONDCHANGEACTIVE || 4877 cmd == SIOCGMIIPHY || 4878 cmd == SIOCGMIIREG || 4879 cmd == SIOCSMIIREG || 4880 cmd == SIOCBRADDIF || 4881 cmd == SIOCBRDELIF || 4882 cmd == SIOCSHWTSTAMP || 4883 cmd == SIOCWANDEV) { 4884 err = -EOPNOTSUPP; 4885 if (ops->ndo_do_ioctl) { 4886 if (netif_device_present(dev)) 4887 err = ops->ndo_do_ioctl(dev, ifr, cmd); 4888 else 4889 err = -ENODEV; 4890 } 4891 } else 4892 err = -EINVAL; 4893 4894 } 4895 return err; 4896 } 4897 4898 /* 4899 * This function handles all "interface"-type I/O control requests. The actual 4900 * 'doing' part of this is dev_ifsioc above. 4901 */ 4902 4903 /** 4904 * dev_ioctl - network device ioctl 4905 * @net: the applicable net namespace 4906 * @cmd: command to issue 4907 * @arg: pointer to a struct ifreq in user space 4908 * 4909 * Issue ioctl functions to devices. This is normally called by the 4910 * user space syscall interfaces but can sometimes be useful for 4911 * other purposes. The return value is the return from the syscall if 4912 * positive or a negative errno code on error. 4913 */ 4914 4915 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg) 4916 { 4917 struct ifreq ifr; 4918 int ret; 4919 char *colon; 4920 4921 /* One special case: SIOCGIFCONF takes ifconf argument 4922 and requires shared lock, because it sleeps writing 4923 to user space. 4924 */ 4925 4926 if (cmd == SIOCGIFCONF) { 4927 rtnl_lock(); 4928 ret = dev_ifconf(net, (char __user *) arg); 4929 rtnl_unlock(); 4930 return ret; 4931 } 4932 if (cmd == SIOCGIFNAME) 4933 return dev_ifname(net, (struct ifreq __user *)arg); 4934 4935 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 4936 return -EFAULT; 4937 4938 ifr.ifr_name[IFNAMSIZ-1] = 0; 4939 4940 colon = strchr(ifr.ifr_name, ':'); 4941 if (colon) 4942 *colon = 0; 4943 4944 /* 4945 * See which interface the caller is talking about. 4946 */ 4947 4948 switch (cmd) { 4949 /* 4950 * These ioctl calls: 4951 * - can be done by all. 4952 * - atomic and do not require locking. 4953 * - return a value 4954 */ 4955 case SIOCGIFFLAGS: 4956 case SIOCGIFMETRIC: 4957 case SIOCGIFMTU: 4958 case SIOCGIFHWADDR: 4959 case SIOCGIFSLAVE: 4960 case SIOCGIFMAP: 4961 case SIOCGIFINDEX: 4962 case SIOCGIFTXQLEN: 4963 dev_load(net, ifr.ifr_name); 4964 rcu_read_lock(); 4965 ret = dev_ifsioc_locked(net, &ifr, cmd); 4966 rcu_read_unlock(); 4967 if (!ret) { 4968 if (colon) 4969 *colon = ':'; 4970 if (copy_to_user(arg, &ifr, 4971 sizeof(struct ifreq))) 4972 ret = -EFAULT; 4973 } 4974 return ret; 4975 4976 case SIOCETHTOOL: 4977 dev_load(net, ifr.ifr_name); 4978 rtnl_lock(); 4979 ret = dev_ethtool(net, &ifr); 4980 rtnl_unlock(); 4981 if (!ret) { 4982 if (colon) 4983 *colon = ':'; 4984 if (copy_to_user(arg, &ifr, 4985 sizeof(struct ifreq))) 4986 ret = -EFAULT; 4987 } 4988 return ret; 4989 4990 /* 4991 * These ioctl calls: 4992 * - require superuser power. 4993 * - require strict serialization. 4994 * - return a value 4995 */ 4996 case SIOCGMIIPHY: 4997 case SIOCGMIIREG: 4998 case SIOCSIFNAME: 4999 if (!capable(CAP_NET_ADMIN)) 5000 return -EPERM; 5001 dev_load(net, ifr.ifr_name); 5002 rtnl_lock(); 5003 ret = dev_ifsioc(net, &ifr, cmd); 5004 rtnl_unlock(); 5005 if (!ret) { 5006 if (colon) 5007 *colon = ':'; 5008 if (copy_to_user(arg, &ifr, 5009 sizeof(struct ifreq))) 5010 ret = -EFAULT; 5011 } 5012 return ret; 5013 5014 /* 5015 * These ioctl calls: 5016 * - require superuser power. 5017 * - require strict serialization. 5018 * - do not return a value 5019 */ 5020 case SIOCSIFFLAGS: 5021 case SIOCSIFMETRIC: 5022 case SIOCSIFMTU: 5023 case SIOCSIFMAP: 5024 case SIOCSIFHWADDR: 5025 case SIOCSIFSLAVE: 5026 case SIOCADDMULTI: 5027 case SIOCDELMULTI: 5028 case SIOCSIFHWBROADCAST: 5029 case SIOCSIFTXQLEN: 5030 case SIOCSMIIREG: 5031 case SIOCBONDENSLAVE: 5032 case SIOCBONDRELEASE: 5033 case SIOCBONDSETHWADDR: 5034 case SIOCBONDCHANGEACTIVE: 5035 case SIOCBRADDIF: 5036 case SIOCBRDELIF: 5037 case SIOCSHWTSTAMP: 5038 if (!capable(CAP_NET_ADMIN)) 5039 return -EPERM; 5040 /* fall through */ 5041 case SIOCBONDSLAVEINFOQUERY: 5042 case SIOCBONDINFOQUERY: 5043 dev_load(net, ifr.ifr_name); 5044 rtnl_lock(); 5045 ret = dev_ifsioc(net, &ifr, cmd); 5046 rtnl_unlock(); 5047 return ret; 5048 5049 case SIOCGIFMEM: 5050 /* Get the per device memory space. We can add this but 5051 * currently do not support it */ 5052 case SIOCSIFMEM: 5053 /* Set the per device memory buffer space. 5054 * Not applicable in our case */ 5055 case SIOCSIFLINK: 5056 return -ENOTTY; 5057 5058 /* 5059 * Unknown or private ioctl. 5060 */ 5061 default: 5062 if (cmd == SIOCWANDEV || 5063 (cmd >= SIOCDEVPRIVATE && 5064 cmd <= SIOCDEVPRIVATE + 15)) { 5065 dev_load(net, ifr.ifr_name); 5066 rtnl_lock(); 5067 ret = dev_ifsioc(net, &ifr, cmd); 5068 rtnl_unlock(); 5069 if (!ret && copy_to_user(arg, &ifr, 5070 sizeof(struct ifreq))) 5071 ret = -EFAULT; 5072 return ret; 5073 } 5074 /* Take care of Wireless Extensions */ 5075 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) 5076 return wext_handle_ioctl(net, &ifr, cmd, arg); 5077 return -ENOTTY; 5078 } 5079 } 5080 5081 5082 /** 5083 * dev_new_index - allocate an ifindex 5084 * @net: the applicable net namespace 5085 * 5086 * Returns a suitable unique value for a new device interface 5087 * number. The caller must hold the rtnl semaphore or the 5088 * dev_base_lock to be sure it remains unique. 5089 */ 5090 static int dev_new_index(struct net *net) 5091 { 5092 static int ifindex; 5093 for (;;) { 5094 if (++ifindex <= 0) 5095 ifindex = 1; 5096 if (!__dev_get_by_index(net, ifindex)) 5097 return ifindex; 5098 } 5099 } 5100 5101 /* Delayed registration/unregisteration */ 5102 static LIST_HEAD(net_todo_list); 5103 5104 static void net_set_todo(struct net_device *dev) 5105 { 5106 list_add_tail(&dev->todo_list, &net_todo_list); 5107 } 5108 5109 static void rollback_registered_many(struct list_head *head) 5110 { 5111 struct net_device *dev, *tmp; 5112 5113 BUG_ON(dev_boot_phase); 5114 ASSERT_RTNL(); 5115 5116 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 5117 /* Some devices call without registering 5118 * for initialization unwind. Remove those 5119 * devices and proceed with the remaining. 5120 */ 5121 if (dev->reg_state == NETREG_UNINITIALIZED) { 5122 pr_debug("unregister_netdevice: device %s/%p never " 5123 "was registered\n", dev->name, dev); 5124 5125 WARN_ON(1); 5126 list_del(&dev->unreg_list); 5127 continue; 5128 } 5129 dev->dismantle = true; 5130 BUG_ON(dev->reg_state != NETREG_REGISTERED); 5131 } 5132 5133 /* If device is running, close it first. */ 5134 dev_close_many(head); 5135 5136 list_for_each_entry(dev, head, unreg_list) { 5137 /* And unlink it from device chain. */ 5138 unlist_netdevice(dev); 5139 5140 dev->reg_state = NETREG_UNREGISTERING; 5141 } 5142 5143 synchronize_net(); 5144 5145 list_for_each_entry(dev, head, unreg_list) { 5146 /* Shutdown queueing discipline. */ 5147 dev_shutdown(dev); 5148 5149 5150 /* Notify protocols, that we are about to destroy 5151 this device. They should clean all the things. 5152 */ 5153 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5154 5155 if (!dev->rtnl_link_ops || 5156 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 5157 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U); 5158 5159 /* 5160 * Flush the unicast and multicast chains 5161 */ 5162 dev_uc_flush(dev); 5163 dev_mc_flush(dev); 5164 5165 if (dev->netdev_ops->ndo_uninit) 5166 dev->netdev_ops->ndo_uninit(dev); 5167 5168 /* Notifier chain MUST detach us from master device. */ 5169 WARN_ON(dev->master); 5170 5171 /* Remove entries from kobject tree */ 5172 netdev_unregister_kobject(dev); 5173 } 5174 5175 /* Process any work delayed until the end of the batch */ 5176 dev = list_first_entry(head, struct net_device, unreg_list); 5177 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 5178 5179 rcu_barrier(); 5180 5181 list_for_each_entry(dev, head, unreg_list) 5182 dev_put(dev); 5183 } 5184 5185 static void rollback_registered(struct net_device *dev) 5186 { 5187 LIST_HEAD(single); 5188 5189 list_add(&dev->unreg_list, &single); 5190 rollback_registered_many(&single); 5191 list_del(&single); 5192 } 5193 5194 u32 netdev_fix_features(struct net_device *dev, u32 features) 5195 { 5196 /* Fix illegal checksum combinations */ 5197 if ((features & NETIF_F_HW_CSUM) && 5198 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5199 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 5200 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 5201 } 5202 5203 if ((features & NETIF_F_NO_CSUM) && 5204 (features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5205 netdev_warn(dev, "mixed no checksumming and other settings.\n"); 5206 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM); 5207 } 5208 5209 /* Fix illegal SG+CSUM combinations. */ 5210 if ((features & NETIF_F_SG) && 5211 !(features & NETIF_F_ALL_CSUM)) { 5212 netdev_dbg(dev, 5213 "Dropping NETIF_F_SG since no checksum feature.\n"); 5214 features &= ~NETIF_F_SG; 5215 } 5216 5217 /* TSO requires that SG is present as well. */ 5218 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 5219 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 5220 features &= ~NETIF_F_ALL_TSO; 5221 } 5222 5223 /* TSO ECN requires that TSO is present as well. */ 5224 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 5225 features &= ~NETIF_F_TSO_ECN; 5226 5227 /* Software GSO depends on SG. */ 5228 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 5229 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 5230 features &= ~NETIF_F_GSO; 5231 } 5232 5233 /* UFO needs SG and checksumming */ 5234 if (features & NETIF_F_UFO) { 5235 /* maybe split UFO into V4 and V6? */ 5236 if (!((features & NETIF_F_GEN_CSUM) || 5237 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM)) 5238 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5239 netdev_dbg(dev, 5240 "Dropping NETIF_F_UFO since no checksum offload features.\n"); 5241 features &= ~NETIF_F_UFO; 5242 } 5243 5244 if (!(features & NETIF_F_SG)) { 5245 netdev_dbg(dev, 5246 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n"); 5247 features &= ~NETIF_F_UFO; 5248 } 5249 } 5250 5251 return features; 5252 } 5253 EXPORT_SYMBOL(netdev_fix_features); 5254 5255 int __netdev_update_features(struct net_device *dev) 5256 { 5257 u32 features; 5258 int err = 0; 5259 5260 ASSERT_RTNL(); 5261 5262 features = netdev_get_wanted_features(dev); 5263 5264 if (dev->netdev_ops->ndo_fix_features) 5265 features = dev->netdev_ops->ndo_fix_features(dev, features); 5266 5267 /* driver might be less strict about feature dependencies */ 5268 features = netdev_fix_features(dev, features); 5269 5270 if (dev->features == features) 5271 return 0; 5272 5273 netdev_dbg(dev, "Features changed: 0x%08x -> 0x%08x\n", 5274 dev->features, features); 5275 5276 if (dev->netdev_ops->ndo_set_features) 5277 err = dev->netdev_ops->ndo_set_features(dev, features); 5278 5279 if (unlikely(err < 0)) { 5280 netdev_err(dev, 5281 "set_features() failed (%d); wanted 0x%08x, left 0x%08x\n", 5282 err, features, dev->features); 5283 return -1; 5284 } 5285 5286 if (!err) 5287 dev->features = features; 5288 5289 return 1; 5290 } 5291 5292 /** 5293 * netdev_update_features - recalculate device features 5294 * @dev: the device to check 5295 * 5296 * Recalculate dev->features set and send notifications if it 5297 * has changed. Should be called after driver or hardware dependent 5298 * conditions might have changed that influence the features. 5299 */ 5300 void netdev_update_features(struct net_device *dev) 5301 { 5302 if (__netdev_update_features(dev)) 5303 netdev_features_change(dev); 5304 } 5305 EXPORT_SYMBOL(netdev_update_features); 5306 5307 /** 5308 * netdev_change_features - recalculate device features 5309 * @dev: the device to check 5310 * 5311 * Recalculate dev->features set and send notifications even 5312 * if they have not changed. Should be called instead of 5313 * netdev_update_features() if also dev->vlan_features might 5314 * have changed to allow the changes to be propagated to stacked 5315 * VLAN devices. 5316 */ 5317 void netdev_change_features(struct net_device *dev) 5318 { 5319 __netdev_update_features(dev); 5320 netdev_features_change(dev); 5321 } 5322 EXPORT_SYMBOL(netdev_change_features); 5323 5324 /** 5325 * netif_stacked_transfer_operstate - transfer operstate 5326 * @rootdev: the root or lower level device to transfer state from 5327 * @dev: the device to transfer operstate to 5328 * 5329 * Transfer operational state from root to device. This is normally 5330 * called when a stacking relationship exists between the root 5331 * device and the device(a leaf device). 5332 */ 5333 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 5334 struct net_device *dev) 5335 { 5336 if (rootdev->operstate == IF_OPER_DORMANT) 5337 netif_dormant_on(dev); 5338 else 5339 netif_dormant_off(dev); 5340 5341 if (netif_carrier_ok(rootdev)) { 5342 if (!netif_carrier_ok(dev)) 5343 netif_carrier_on(dev); 5344 } else { 5345 if (netif_carrier_ok(dev)) 5346 netif_carrier_off(dev); 5347 } 5348 } 5349 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 5350 5351 #ifdef CONFIG_RPS 5352 static int netif_alloc_rx_queues(struct net_device *dev) 5353 { 5354 unsigned int i, count = dev->num_rx_queues; 5355 struct netdev_rx_queue *rx; 5356 5357 BUG_ON(count < 1); 5358 5359 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL); 5360 if (!rx) { 5361 pr_err("netdev: Unable to allocate %u rx queues.\n", count); 5362 return -ENOMEM; 5363 } 5364 dev->_rx = rx; 5365 5366 for (i = 0; i < count; i++) 5367 rx[i].dev = dev; 5368 return 0; 5369 } 5370 #endif 5371 5372 static void netdev_init_one_queue(struct net_device *dev, 5373 struct netdev_queue *queue, void *_unused) 5374 { 5375 /* Initialize queue lock */ 5376 spin_lock_init(&queue->_xmit_lock); 5377 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 5378 queue->xmit_lock_owner = -1; 5379 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 5380 queue->dev = dev; 5381 } 5382 5383 static int netif_alloc_netdev_queues(struct net_device *dev) 5384 { 5385 unsigned int count = dev->num_tx_queues; 5386 struct netdev_queue *tx; 5387 5388 BUG_ON(count < 1); 5389 5390 tx = kcalloc(count, sizeof(struct netdev_queue), GFP_KERNEL); 5391 if (!tx) { 5392 pr_err("netdev: Unable to allocate %u tx queues.\n", 5393 count); 5394 return -ENOMEM; 5395 } 5396 dev->_tx = tx; 5397 5398 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 5399 spin_lock_init(&dev->tx_global_lock); 5400 5401 return 0; 5402 } 5403 5404 /** 5405 * register_netdevice - register a network device 5406 * @dev: device to register 5407 * 5408 * Take a completed network device structure and add it to the kernel 5409 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 5410 * chain. 0 is returned on success. A negative errno code is returned 5411 * on a failure to set up the device, or if the name is a duplicate. 5412 * 5413 * Callers must hold the rtnl semaphore. You may want 5414 * register_netdev() instead of this. 5415 * 5416 * BUGS: 5417 * The locking appears insufficient to guarantee two parallel registers 5418 * will not get the same name. 5419 */ 5420 5421 int register_netdevice(struct net_device *dev) 5422 { 5423 int ret; 5424 struct net *net = dev_net(dev); 5425 5426 BUG_ON(dev_boot_phase); 5427 ASSERT_RTNL(); 5428 5429 might_sleep(); 5430 5431 /* When net_device's are persistent, this will be fatal. */ 5432 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 5433 BUG_ON(!net); 5434 5435 spin_lock_init(&dev->addr_list_lock); 5436 netdev_set_addr_lockdep_class(dev); 5437 5438 dev->iflink = -1; 5439 5440 ret = dev_get_valid_name(dev, dev->name); 5441 if (ret < 0) 5442 goto out; 5443 5444 /* Init, if this function is available */ 5445 if (dev->netdev_ops->ndo_init) { 5446 ret = dev->netdev_ops->ndo_init(dev); 5447 if (ret) { 5448 if (ret > 0) 5449 ret = -EIO; 5450 goto out; 5451 } 5452 } 5453 5454 dev->ifindex = dev_new_index(net); 5455 if (dev->iflink == -1) 5456 dev->iflink = dev->ifindex; 5457 5458 /* Transfer changeable features to wanted_features and enable 5459 * software offloads (GSO and GRO). 5460 */ 5461 dev->hw_features |= NETIF_F_SOFT_FEATURES; 5462 dev->features |= NETIF_F_SOFT_FEATURES; 5463 dev->wanted_features = dev->features & dev->hw_features; 5464 5465 /* Turn on no cache copy if HW is doing checksum */ 5466 dev->hw_features |= NETIF_F_NOCACHE_COPY; 5467 if ((dev->features & NETIF_F_ALL_CSUM) && 5468 !(dev->features & NETIF_F_NO_CSUM)) { 5469 dev->wanted_features |= NETIF_F_NOCACHE_COPY; 5470 dev->features |= NETIF_F_NOCACHE_COPY; 5471 } 5472 5473 /* Enable GRO and NETIF_F_HIGHDMA for vlans by default, 5474 * vlan_dev_init() will do the dev->features check, so these features 5475 * are enabled only if supported by underlying device. 5476 */ 5477 dev->vlan_features |= (NETIF_F_GRO | NETIF_F_HIGHDMA); 5478 5479 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 5480 ret = notifier_to_errno(ret); 5481 if (ret) 5482 goto err_uninit; 5483 5484 ret = netdev_register_kobject(dev); 5485 if (ret) 5486 goto err_uninit; 5487 dev->reg_state = NETREG_REGISTERED; 5488 5489 __netdev_update_features(dev); 5490 5491 /* 5492 * Default initial state at registry is that the 5493 * device is present. 5494 */ 5495 5496 set_bit(__LINK_STATE_PRESENT, &dev->state); 5497 5498 dev_init_scheduler(dev); 5499 dev_hold(dev); 5500 list_netdevice(dev); 5501 5502 /* Notify protocols, that a new device appeared. */ 5503 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 5504 ret = notifier_to_errno(ret); 5505 if (ret) { 5506 rollback_registered(dev); 5507 dev->reg_state = NETREG_UNREGISTERED; 5508 } 5509 /* 5510 * Prevent userspace races by waiting until the network 5511 * device is fully setup before sending notifications. 5512 */ 5513 if (!dev->rtnl_link_ops || 5514 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 5515 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 5516 5517 out: 5518 return ret; 5519 5520 err_uninit: 5521 if (dev->netdev_ops->ndo_uninit) 5522 dev->netdev_ops->ndo_uninit(dev); 5523 goto out; 5524 } 5525 EXPORT_SYMBOL(register_netdevice); 5526 5527 /** 5528 * init_dummy_netdev - init a dummy network device for NAPI 5529 * @dev: device to init 5530 * 5531 * This takes a network device structure and initialize the minimum 5532 * amount of fields so it can be used to schedule NAPI polls without 5533 * registering a full blown interface. This is to be used by drivers 5534 * that need to tie several hardware interfaces to a single NAPI 5535 * poll scheduler due to HW limitations. 5536 */ 5537 int init_dummy_netdev(struct net_device *dev) 5538 { 5539 /* Clear everything. Note we don't initialize spinlocks 5540 * are they aren't supposed to be taken by any of the 5541 * NAPI code and this dummy netdev is supposed to be 5542 * only ever used for NAPI polls 5543 */ 5544 memset(dev, 0, sizeof(struct net_device)); 5545 5546 /* make sure we BUG if trying to hit standard 5547 * register/unregister code path 5548 */ 5549 dev->reg_state = NETREG_DUMMY; 5550 5551 /* NAPI wants this */ 5552 INIT_LIST_HEAD(&dev->napi_list); 5553 5554 /* a dummy interface is started by default */ 5555 set_bit(__LINK_STATE_PRESENT, &dev->state); 5556 set_bit(__LINK_STATE_START, &dev->state); 5557 5558 /* Note : We dont allocate pcpu_refcnt for dummy devices, 5559 * because users of this 'device' dont need to change 5560 * its refcount. 5561 */ 5562 5563 return 0; 5564 } 5565 EXPORT_SYMBOL_GPL(init_dummy_netdev); 5566 5567 5568 /** 5569 * register_netdev - register a network device 5570 * @dev: device to register 5571 * 5572 * Take a completed network device structure and add it to the kernel 5573 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 5574 * chain. 0 is returned on success. A negative errno code is returned 5575 * on a failure to set up the device, or if the name is a duplicate. 5576 * 5577 * This is a wrapper around register_netdevice that takes the rtnl semaphore 5578 * and expands the device name if you passed a format string to 5579 * alloc_netdev. 5580 */ 5581 int register_netdev(struct net_device *dev) 5582 { 5583 int err; 5584 5585 rtnl_lock(); 5586 err = register_netdevice(dev); 5587 rtnl_unlock(); 5588 return err; 5589 } 5590 EXPORT_SYMBOL(register_netdev); 5591 5592 int netdev_refcnt_read(const struct net_device *dev) 5593 { 5594 int i, refcnt = 0; 5595 5596 for_each_possible_cpu(i) 5597 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 5598 return refcnt; 5599 } 5600 EXPORT_SYMBOL(netdev_refcnt_read); 5601 5602 /* 5603 * netdev_wait_allrefs - wait until all references are gone. 5604 * 5605 * This is called when unregistering network devices. 5606 * 5607 * Any protocol or device that holds a reference should register 5608 * for netdevice notification, and cleanup and put back the 5609 * reference if they receive an UNREGISTER event. 5610 * We can get stuck here if buggy protocols don't correctly 5611 * call dev_put. 5612 */ 5613 static void netdev_wait_allrefs(struct net_device *dev) 5614 { 5615 unsigned long rebroadcast_time, warning_time; 5616 int refcnt; 5617 5618 linkwatch_forget_dev(dev); 5619 5620 rebroadcast_time = warning_time = jiffies; 5621 refcnt = netdev_refcnt_read(dev); 5622 5623 while (refcnt != 0) { 5624 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 5625 rtnl_lock(); 5626 5627 /* Rebroadcast unregister notification */ 5628 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5629 /* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users 5630 * should have already handle it the first time */ 5631 5632 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 5633 &dev->state)) { 5634 /* We must not have linkwatch events 5635 * pending on unregister. If this 5636 * happens, we simply run the queue 5637 * unscheduled, resulting in a noop 5638 * for this device. 5639 */ 5640 linkwatch_run_queue(); 5641 } 5642 5643 __rtnl_unlock(); 5644 5645 rebroadcast_time = jiffies; 5646 } 5647 5648 msleep(250); 5649 5650 refcnt = netdev_refcnt_read(dev); 5651 5652 if (time_after(jiffies, warning_time + 10 * HZ)) { 5653 printk(KERN_EMERG "unregister_netdevice: " 5654 "waiting for %s to become free. Usage " 5655 "count = %d\n", 5656 dev->name, refcnt); 5657 warning_time = jiffies; 5658 } 5659 } 5660 } 5661 5662 /* The sequence is: 5663 * 5664 * rtnl_lock(); 5665 * ... 5666 * register_netdevice(x1); 5667 * register_netdevice(x2); 5668 * ... 5669 * unregister_netdevice(y1); 5670 * unregister_netdevice(y2); 5671 * ... 5672 * rtnl_unlock(); 5673 * free_netdev(y1); 5674 * free_netdev(y2); 5675 * 5676 * We are invoked by rtnl_unlock(). 5677 * This allows us to deal with problems: 5678 * 1) We can delete sysfs objects which invoke hotplug 5679 * without deadlocking with linkwatch via keventd. 5680 * 2) Since we run with the RTNL semaphore not held, we can sleep 5681 * safely in order to wait for the netdev refcnt to drop to zero. 5682 * 5683 * We must not return until all unregister events added during 5684 * the interval the lock was held have been completed. 5685 */ 5686 void netdev_run_todo(void) 5687 { 5688 struct list_head list; 5689 5690 /* Snapshot list, allow later requests */ 5691 list_replace_init(&net_todo_list, &list); 5692 5693 __rtnl_unlock(); 5694 5695 while (!list_empty(&list)) { 5696 struct net_device *dev 5697 = list_first_entry(&list, struct net_device, todo_list); 5698 list_del(&dev->todo_list); 5699 5700 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 5701 printk(KERN_ERR "network todo '%s' but state %d\n", 5702 dev->name, dev->reg_state); 5703 dump_stack(); 5704 continue; 5705 } 5706 5707 dev->reg_state = NETREG_UNREGISTERED; 5708 5709 on_each_cpu(flush_backlog, dev, 1); 5710 5711 netdev_wait_allrefs(dev); 5712 5713 /* paranoia */ 5714 BUG_ON(netdev_refcnt_read(dev)); 5715 WARN_ON(rcu_dereference_raw(dev->ip_ptr)); 5716 WARN_ON(rcu_dereference_raw(dev->ip6_ptr)); 5717 WARN_ON(dev->dn_ptr); 5718 5719 if (dev->destructor) 5720 dev->destructor(dev); 5721 5722 /* Free network device */ 5723 kobject_put(&dev->dev.kobj); 5724 } 5725 } 5726 5727 /* Convert net_device_stats to rtnl_link_stats64. They have the same 5728 * fields in the same order, with only the type differing. 5729 */ 5730 static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 5731 const struct net_device_stats *netdev_stats) 5732 { 5733 #if BITS_PER_LONG == 64 5734 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats)); 5735 memcpy(stats64, netdev_stats, sizeof(*stats64)); 5736 #else 5737 size_t i, n = sizeof(*stats64) / sizeof(u64); 5738 const unsigned long *src = (const unsigned long *)netdev_stats; 5739 u64 *dst = (u64 *)stats64; 5740 5741 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) != 5742 sizeof(*stats64) / sizeof(u64)); 5743 for (i = 0; i < n; i++) 5744 dst[i] = src[i]; 5745 #endif 5746 } 5747 5748 /** 5749 * dev_get_stats - get network device statistics 5750 * @dev: device to get statistics from 5751 * @storage: place to store stats 5752 * 5753 * Get network statistics from device. Return @storage. 5754 * The device driver may provide its own method by setting 5755 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 5756 * otherwise the internal statistics structure is used. 5757 */ 5758 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 5759 struct rtnl_link_stats64 *storage) 5760 { 5761 const struct net_device_ops *ops = dev->netdev_ops; 5762 5763 if (ops->ndo_get_stats64) { 5764 memset(storage, 0, sizeof(*storage)); 5765 ops->ndo_get_stats64(dev, storage); 5766 } else if (ops->ndo_get_stats) { 5767 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 5768 } else { 5769 netdev_stats_to_stats64(storage, &dev->stats); 5770 } 5771 storage->rx_dropped += atomic_long_read(&dev->rx_dropped); 5772 return storage; 5773 } 5774 EXPORT_SYMBOL(dev_get_stats); 5775 5776 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 5777 { 5778 struct netdev_queue *queue = dev_ingress_queue(dev); 5779 5780 #ifdef CONFIG_NET_CLS_ACT 5781 if (queue) 5782 return queue; 5783 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 5784 if (!queue) 5785 return NULL; 5786 netdev_init_one_queue(dev, queue, NULL); 5787 queue->qdisc = &noop_qdisc; 5788 queue->qdisc_sleeping = &noop_qdisc; 5789 rcu_assign_pointer(dev->ingress_queue, queue); 5790 #endif 5791 return queue; 5792 } 5793 5794 /** 5795 * alloc_netdev_mqs - allocate network device 5796 * @sizeof_priv: size of private data to allocate space for 5797 * @name: device name format string 5798 * @setup: callback to initialize device 5799 * @txqs: the number of TX subqueues to allocate 5800 * @rxqs: the number of RX subqueues to allocate 5801 * 5802 * Allocates a struct net_device with private data area for driver use 5803 * and performs basic initialization. Also allocates subquue structs 5804 * for each queue on the device. 5805 */ 5806 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 5807 void (*setup)(struct net_device *), 5808 unsigned int txqs, unsigned int rxqs) 5809 { 5810 struct net_device *dev; 5811 size_t alloc_size; 5812 struct net_device *p; 5813 5814 BUG_ON(strlen(name) >= sizeof(dev->name)); 5815 5816 if (txqs < 1) { 5817 pr_err("alloc_netdev: Unable to allocate device " 5818 "with zero queues.\n"); 5819 return NULL; 5820 } 5821 5822 #ifdef CONFIG_RPS 5823 if (rxqs < 1) { 5824 pr_err("alloc_netdev: Unable to allocate device " 5825 "with zero RX queues.\n"); 5826 return NULL; 5827 } 5828 #endif 5829 5830 alloc_size = sizeof(struct net_device); 5831 if (sizeof_priv) { 5832 /* ensure 32-byte alignment of private area */ 5833 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 5834 alloc_size += sizeof_priv; 5835 } 5836 /* ensure 32-byte alignment of whole construct */ 5837 alloc_size += NETDEV_ALIGN - 1; 5838 5839 p = kzalloc(alloc_size, GFP_KERNEL); 5840 if (!p) { 5841 printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n"); 5842 return NULL; 5843 } 5844 5845 dev = PTR_ALIGN(p, NETDEV_ALIGN); 5846 dev->padded = (char *)dev - (char *)p; 5847 5848 dev->pcpu_refcnt = alloc_percpu(int); 5849 if (!dev->pcpu_refcnt) 5850 goto free_p; 5851 5852 if (dev_addr_init(dev)) 5853 goto free_pcpu; 5854 5855 dev_mc_init(dev); 5856 dev_uc_init(dev); 5857 5858 dev_net_set(dev, &init_net); 5859 5860 dev->gso_max_size = GSO_MAX_SIZE; 5861 5862 INIT_LIST_HEAD(&dev->ethtool_ntuple_list.list); 5863 dev->ethtool_ntuple_list.count = 0; 5864 INIT_LIST_HEAD(&dev->napi_list); 5865 INIT_LIST_HEAD(&dev->unreg_list); 5866 INIT_LIST_HEAD(&dev->link_watch_list); 5867 dev->priv_flags = IFF_XMIT_DST_RELEASE; 5868 setup(dev); 5869 5870 dev->num_tx_queues = txqs; 5871 dev->real_num_tx_queues = txqs; 5872 if (netif_alloc_netdev_queues(dev)) 5873 goto free_all; 5874 5875 #ifdef CONFIG_RPS 5876 dev->num_rx_queues = rxqs; 5877 dev->real_num_rx_queues = rxqs; 5878 if (netif_alloc_rx_queues(dev)) 5879 goto free_all; 5880 #endif 5881 5882 strcpy(dev->name, name); 5883 dev->group = INIT_NETDEV_GROUP; 5884 return dev; 5885 5886 free_all: 5887 free_netdev(dev); 5888 return NULL; 5889 5890 free_pcpu: 5891 free_percpu(dev->pcpu_refcnt); 5892 kfree(dev->_tx); 5893 #ifdef CONFIG_RPS 5894 kfree(dev->_rx); 5895 #endif 5896 5897 free_p: 5898 kfree(p); 5899 return NULL; 5900 } 5901 EXPORT_SYMBOL(alloc_netdev_mqs); 5902 5903 /** 5904 * free_netdev - free network device 5905 * @dev: device 5906 * 5907 * This function does the last stage of destroying an allocated device 5908 * interface. The reference to the device object is released. 5909 * If this is the last reference then it will be freed. 5910 */ 5911 void free_netdev(struct net_device *dev) 5912 { 5913 struct napi_struct *p, *n; 5914 5915 release_net(dev_net(dev)); 5916 5917 kfree(dev->_tx); 5918 #ifdef CONFIG_RPS 5919 kfree(dev->_rx); 5920 #endif 5921 5922 kfree(rcu_dereference_raw(dev->ingress_queue)); 5923 5924 /* Flush device addresses */ 5925 dev_addr_flush(dev); 5926 5927 /* Clear ethtool n-tuple list */ 5928 ethtool_ntuple_flush(dev); 5929 5930 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 5931 netif_napi_del(p); 5932 5933 free_percpu(dev->pcpu_refcnt); 5934 dev->pcpu_refcnt = NULL; 5935 5936 /* Compatibility with error handling in drivers */ 5937 if (dev->reg_state == NETREG_UNINITIALIZED) { 5938 kfree((char *)dev - dev->padded); 5939 return; 5940 } 5941 5942 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 5943 dev->reg_state = NETREG_RELEASED; 5944 5945 /* will free via device release */ 5946 put_device(&dev->dev); 5947 } 5948 EXPORT_SYMBOL(free_netdev); 5949 5950 /** 5951 * synchronize_net - Synchronize with packet receive processing 5952 * 5953 * Wait for packets currently being received to be done. 5954 * Does not block later packets from starting. 5955 */ 5956 void synchronize_net(void) 5957 { 5958 might_sleep(); 5959 synchronize_rcu(); 5960 } 5961 EXPORT_SYMBOL(synchronize_net); 5962 5963 /** 5964 * unregister_netdevice_queue - remove device from the kernel 5965 * @dev: device 5966 * @head: list 5967 * 5968 * This function shuts down a device interface and removes it 5969 * from the kernel tables. 5970 * If head not NULL, device is queued to be unregistered later. 5971 * 5972 * Callers must hold the rtnl semaphore. You may want 5973 * unregister_netdev() instead of this. 5974 */ 5975 5976 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 5977 { 5978 ASSERT_RTNL(); 5979 5980 if (head) { 5981 list_move_tail(&dev->unreg_list, head); 5982 } else { 5983 rollback_registered(dev); 5984 /* Finish processing unregister after unlock */ 5985 net_set_todo(dev); 5986 } 5987 } 5988 EXPORT_SYMBOL(unregister_netdevice_queue); 5989 5990 /** 5991 * unregister_netdevice_many - unregister many devices 5992 * @head: list of devices 5993 */ 5994 void unregister_netdevice_many(struct list_head *head) 5995 { 5996 struct net_device *dev; 5997 5998 if (!list_empty(head)) { 5999 rollback_registered_many(head); 6000 list_for_each_entry(dev, head, unreg_list) 6001 net_set_todo(dev); 6002 } 6003 } 6004 EXPORT_SYMBOL(unregister_netdevice_many); 6005 6006 /** 6007 * unregister_netdev - remove device from the kernel 6008 * @dev: device 6009 * 6010 * This function shuts down a device interface and removes it 6011 * from the kernel tables. 6012 * 6013 * This is just a wrapper for unregister_netdevice that takes 6014 * the rtnl semaphore. In general you want to use this and not 6015 * unregister_netdevice. 6016 */ 6017 void unregister_netdev(struct net_device *dev) 6018 { 6019 rtnl_lock(); 6020 unregister_netdevice(dev); 6021 rtnl_unlock(); 6022 } 6023 EXPORT_SYMBOL(unregister_netdev); 6024 6025 /** 6026 * dev_change_net_namespace - move device to different nethost namespace 6027 * @dev: device 6028 * @net: network namespace 6029 * @pat: If not NULL name pattern to try if the current device name 6030 * is already taken in the destination network namespace. 6031 * 6032 * This function shuts down a device interface and moves it 6033 * to a new network namespace. On success 0 is returned, on 6034 * a failure a netagive errno code is returned. 6035 * 6036 * Callers must hold the rtnl semaphore. 6037 */ 6038 6039 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat) 6040 { 6041 int err; 6042 6043 ASSERT_RTNL(); 6044 6045 /* Don't allow namespace local devices to be moved. */ 6046 err = -EINVAL; 6047 if (dev->features & NETIF_F_NETNS_LOCAL) 6048 goto out; 6049 6050 /* Ensure the device has been registrered */ 6051 err = -EINVAL; 6052 if (dev->reg_state != NETREG_REGISTERED) 6053 goto out; 6054 6055 /* Get out if there is nothing todo */ 6056 err = 0; 6057 if (net_eq(dev_net(dev), net)) 6058 goto out; 6059 6060 /* Pick the destination device name, and ensure 6061 * we can use it in the destination network namespace. 6062 */ 6063 err = -EEXIST; 6064 if (__dev_get_by_name(net, dev->name)) { 6065 /* We get here if we can't use the current device name */ 6066 if (!pat) 6067 goto out; 6068 if (dev_get_valid_name(dev, pat) < 0) 6069 goto out; 6070 } 6071 6072 /* 6073 * And now a mini version of register_netdevice unregister_netdevice. 6074 */ 6075 6076 /* If device is running close it first. */ 6077 dev_close(dev); 6078 6079 /* And unlink it from device chain */ 6080 err = -ENODEV; 6081 unlist_netdevice(dev); 6082 6083 synchronize_net(); 6084 6085 /* Shutdown queueing discipline. */ 6086 dev_shutdown(dev); 6087 6088 /* Notify protocols, that we are about to destroy 6089 this device. They should clean all the things. 6090 6091 Note that dev->reg_state stays at NETREG_REGISTERED. 6092 This is wanted because this way 8021q and macvlan know 6093 the device is just moving and can keep their slaves up. 6094 */ 6095 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 6096 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 6097 6098 /* 6099 * Flush the unicast and multicast chains 6100 */ 6101 dev_uc_flush(dev); 6102 dev_mc_flush(dev); 6103 6104 /* Actually switch the network namespace */ 6105 dev_net_set(dev, net); 6106 6107 /* If there is an ifindex conflict assign a new one */ 6108 if (__dev_get_by_index(net, dev->ifindex)) { 6109 int iflink = (dev->iflink == dev->ifindex); 6110 dev->ifindex = dev_new_index(net); 6111 if (iflink) 6112 dev->iflink = dev->ifindex; 6113 } 6114 6115 /* Fixup kobjects */ 6116 err = device_rename(&dev->dev, dev->name); 6117 WARN_ON(err); 6118 6119 /* Add the device back in the hashes */ 6120 list_netdevice(dev); 6121 6122 /* Notify protocols, that a new device appeared. */ 6123 call_netdevice_notifiers(NETDEV_REGISTER, dev); 6124 6125 /* 6126 * Prevent userspace races by waiting until the network 6127 * device is fully setup before sending notifications. 6128 */ 6129 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 6130 6131 synchronize_net(); 6132 err = 0; 6133 out: 6134 return err; 6135 } 6136 EXPORT_SYMBOL_GPL(dev_change_net_namespace); 6137 6138 static int dev_cpu_callback(struct notifier_block *nfb, 6139 unsigned long action, 6140 void *ocpu) 6141 { 6142 struct sk_buff **list_skb; 6143 struct sk_buff *skb; 6144 unsigned int cpu, oldcpu = (unsigned long)ocpu; 6145 struct softnet_data *sd, *oldsd; 6146 6147 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) 6148 return NOTIFY_OK; 6149 6150 local_irq_disable(); 6151 cpu = smp_processor_id(); 6152 sd = &per_cpu(softnet_data, cpu); 6153 oldsd = &per_cpu(softnet_data, oldcpu); 6154 6155 /* Find end of our completion_queue. */ 6156 list_skb = &sd->completion_queue; 6157 while (*list_skb) 6158 list_skb = &(*list_skb)->next; 6159 /* Append completion queue from offline CPU. */ 6160 *list_skb = oldsd->completion_queue; 6161 oldsd->completion_queue = NULL; 6162 6163 /* Append output queue from offline CPU. */ 6164 if (oldsd->output_queue) { 6165 *sd->output_queue_tailp = oldsd->output_queue; 6166 sd->output_queue_tailp = oldsd->output_queue_tailp; 6167 oldsd->output_queue = NULL; 6168 oldsd->output_queue_tailp = &oldsd->output_queue; 6169 } 6170 6171 raise_softirq_irqoff(NET_TX_SOFTIRQ); 6172 local_irq_enable(); 6173 6174 /* Process offline CPU's input_pkt_queue */ 6175 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 6176 netif_rx(skb); 6177 input_queue_head_incr(oldsd); 6178 } 6179 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) { 6180 netif_rx(skb); 6181 input_queue_head_incr(oldsd); 6182 } 6183 6184 return NOTIFY_OK; 6185 } 6186 6187 6188 /** 6189 * netdev_increment_features - increment feature set by one 6190 * @all: current feature set 6191 * @one: new feature set 6192 * @mask: mask feature set 6193 * 6194 * Computes a new feature set after adding a device with feature set 6195 * @one to the master device with current feature set @all. Will not 6196 * enable anything that is off in @mask. Returns the new feature set. 6197 */ 6198 u32 netdev_increment_features(u32 all, u32 one, u32 mask) 6199 { 6200 if (mask & NETIF_F_GEN_CSUM) 6201 mask |= NETIF_F_ALL_CSUM; 6202 mask |= NETIF_F_VLAN_CHALLENGED; 6203 6204 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask; 6205 all &= one | ~NETIF_F_ALL_FOR_ALL; 6206 6207 /* If device needs checksumming, downgrade to it. */ 6208 if (all & (NETIF_F_ALL_CSUM & ~NETIF_F_NO_CSUM)) 6209 all &= ~NETIF_F_NO_CSUM; 6210 6211 /* If one device supports hw checksumming, set for all. */ 6212 if (all & NETIF_F_GEN_CSUM) 6213 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); 6214 6215 return all; 6216 } 6217 EXPORT_SYMBOL(netdev_increment_features); 6218 6219 static struct hlist_head *netdev_create_hash(void) 6220 { 6221 int i; 6222 struct hlist_head *hash; 6223 6224 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL); 6225 if (hash != NULL) 6226 for (i = 0; i < NETDEV_HASHENTRIES; i++) 6227 INIT_HLIST_HEAD(&hash[i]); 6228 6229 return hash; 6230 } 6231 6232 /* Initialize per network namespace state */ 6233 static int __net_init netdev_init(struct net *net) 6234 { 6235 INIT_LIST_HEAD(&net->dev_base_head); 6236 6237 net->dev_name_head = netdev_create_hash(); 6238 if (net->dev_name_head == NULL) 6239 goto err_name; 6240 6241 net->dev_index_head = netdev_create_hash(); 6242 if (net->dev_index_head == NULL) 6243 goto err_idx; 6244 6245 return 0; 6246 6247 err_idx: 6248 kfree(net->dev_name_head); 6249 err_name: 6250 return -ENOMEM; 6251 } 6252 6253 /** 6254 * netdev_drivername - network driver for the device 6255 * @dev: network device 6256 * @buffer: buffer for resulting name 6257 * @len: size of buffer 6258 * 6259 * Determine network driver for device. 6260 */ 6261 char *netdev_drivername(const struct net_device *dev, char *buffer, int len) 6262 { 6263 const struct device_driver *driver; 6264 const struct device *parent; 6265 6266 if (len <= 0 || !buffer) 6267 return buffer; 6268 buffer[0] = 0; 6269 6270 parent = dev->dev.parent; 6271 6272 if (!parent) 6273 return buffer; 6274 6275 driver = parent->driver; 6276 if (driver && driver->name) 6277 strlcpy(buffer, driver->name, len); 6278 return buffer; 6279 } 6280 6281 static int __netdev_printk(const char *level, const struct net_device *dev, 6282 struct va_format *vaf) 6283 { 6284 int r; 6285 6286 if (dev && dev->dev.parent) 6287 r = dev_printk(level, dev->dev.parent, "%s: %pV", 6288 netdev_name(dev), vaf); 6289 else if (dev) 6290 r = printk("%s%s: %pV", level, netdev_name(dev), vaf); 6291 else 6292 r = printk("%s(NULL net_device): %pV", level, vaf); 6293 6294 return r; 6295 } 6296 6297 int netdev_printk(const char *level, const struct net_device *dev, 6298 const char *format, ...) 6299 { 6300 struct va_format vaf; 6301 va_list args; 6302 int r; 6303 6304 va_start(args, format); 6305 6306 vaf.fmt = format; 6307 vaf.va = &args; 6308 6309 r = __netdev_printk(level, dev, &vaf); 6310 va_end(args); 6311 6312 return r; 6313 } 6314 EXPORT_SYMBOL(netdev_printk); 6315 6316 #define define_netdev_printk_level(func, level) \ 6317 int func(const struct net_device *dev, const char *fmt, ...) \ 6318 { \ 6319 int r; \ 6320 struct va_format vaf; \ 6321 va_list args; \ 6322 \ 6323 va_start(args, fmt); \ 6324 \ 6325 vaf.fmt = fmt; \ 6326 vaf.va = &args; \ 6327 \ 6328 r = __netdev_printk(level, dev, &vaf); \ 6329 va_end(args); \ 6330 \ 6331 return r; \ 6332 } \ 6333 EXPORT_SYMBOL(func); 6334 6335 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 6336 define_netdev_printk_level(netdev_alert, KERN_ALERT); 6337 define_netdev_printk_level(netdev_crit, KERN_CRIT); 6338 define_netdev_printk_level(netdev_err, KERN_ERR); 6339 define_netdev_printk_level(netdev_warn, KERN_WARNING); 6340 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 6341 define_netdev_printk_level(netdev_info, KERN_INFO); 6342 6343 static void __net_exit netdev_exit(struct net *net) 6344 { 6345 kfree(net->dev_name_head); 6346 kfree(net->dev_index_head); 6347 } 6348 6349 static struct pernet_operations __net_initdata netdev_net_ops = { 6350 .init = netdev_init, 6351 .exit = netdev_exit, 6352 }; 6353 6354 static void __net_exit default_device_exit(struct net *net) 6355 { 6356 struct net_device *dev, *aux; 6357 /* 6358 * Push all migratable network devices back to the 6359 * initial network namespace 6360 */ 6361 rtnl_lock(); 6362 for_each_netdev_safe(net, dev, aux) { 6363 int err; 6364 char fb_name[IFNAMSIZ]; 6365 6366 /* Ignore unmoveable devices (i.e. loopback) */ 6367 if (dev->features & NETIF_F_NETNS_LOCAL) 6368 continue; 6369 6370 /* Leave virtual devices for the generic cleanup */ 6371 if (dev->rtnl_link_ops) 6372 continue; 6373 6374 /* Push remaining network devices to init_net */ 6375 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 6376 err = dev_change_net_namespace(dev, &init_net, fb_name); 6377 if (err) { 6378 printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n", 6379 __func__, dev->name, err); 6380 BUG(); 6381 } 6382 } 6383 rtnl_unlock(); 6384 } 6385 6386 static void __net_exit default_device_exit_batch(struct list_head *net_list) 6387 { 6388 /* At exit all network devices most be removed from a network 6389 * namespace. Do this in the reverse order of registration. 6390 * Do this across as many network namespaces as possible to 6391 * improve batching efficiency. 6392 */ 6393 struct net_device *dev; 6394 struct net *net; 6395 LIST_HEAD(dev_kill_list); 6396 6397 rtnl_lock(); 6398 list_for_each_entry(net, net_list, exit_list) { 6399 for_each_netdev_reverse(net, dev) { 6400 if (dev->rtnl_link_ops) 6401 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 6402 else 6403 unregister_netdevice_queue(dev, &dev_kill_list); 6404 } 6405 } 6406 unregister_netdevice_many(&dev_kill_list); 6407 list_del(&dev_kill_list); 6408 rtnl_unlock(); 6409 } 6410 6411 static struct pernet_operations __net_initdata default_device_ops = { 6412 .exit = default_device_exit, 6413 .exit_batch = default_device_exit_batch, 6414 }; 6415 6416 /* 6417 * Initialize the DEV module. At boot time this walks the device list and 6418 * unhooks any devices that fail to initialise (normally hardware not 6419 * present) and leaves us with a valid list of present and active devices. 6420 * 6421 */ 6422 6423 /* 6424 * This is called single threaded during boot, so no need 6425 * to take the rtnl semaphore. 6426 */ 6427 static int __init net_dev_init(void) 6428 { 6429 int i, rc = -ENOMEM; 6430 6431 BUG_ON(!dev_boot_phase); 6432 6433 if (dev_proc_init()) 6434 goto out; 6435 6436 if (netdev_kobject_init()) 6437 goto out; 6438 6439 INIT_LIST_HEAD(&ptype_all); 6440 for (i = 0; i < PTYPE_HASH_SIZE; i++) 6441 INIT_LIST_HEAD(&ptype_base[i]); 6442 6443 if (register_pernet_subsys(&netdev_net_ops)) 6444 goto out; 6445 6446 /* 6447 * Initialise the packet receive queues. 6448 */ 6449 6450 for_each_possible_cpu(i) { 6451 struct softnet_data *sd = &per_cpu(softnet_data, i); 6452 6453 memset(sd, 0, sizeof(*sd)); 6454 skb_queue_head_init(&sd->input_pkt_queue); 6455 skb_queue_head_init(&sd->process_queue); 6456 sd->completion_queue = NULL; 6457 INIT_LIST_HEAD(&sd->poll_list); 6458 sd->output_queue = NULL; 6459 sd->output_queue_tailp = &sd->output_queue; 6460 #ifdef CONFIG_RPS 6461 sd->csd.func = rps_trigger_softirq; 6462 sd->csd.info = sd; 6463 sd->csd.flags = 0; 6464 sd->cpu = i; 6465 #endif 6466 6467 sd->backlog.poll = process_backlog; 6468 sd->backlog.weight = weight_p; 6469 sd->backlog.gro_list = NULL; 6470 sd->backlog.gro_count = 0; 6471 } 6472 6473 dev_boot_phase = 0; 6474 6475 /* The loopback device is special if any other network devices 6476 * is present in a network namespace the loopback device must 6477 * be present. Since we now dynamically allocate and free the 6478 * loopback device ensure this invariant is maintained by 6479 * keeping the loopback device as the first device on the 6480 * list of network devices. Ensuring the loopback devices 6481 * is the first device that appears and the last network device 6482 * that disappears. 6483 */ 6484 if (register_pernet_device(&loopback_net_ops)) 6485 goto out; 6486 6487 if (register_pernet_device(&default_device_ops)) 6488 goto out; 6489 6490 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 6491 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 6492 6493 hotcpu_notifier(dev_cpu_callback, 0); 6494 dst_init(); 6495 dev_mcast_init(); 6496 rc = 0; 6497 out: 6498 return rc; 6499 } 6500 6501 subsys_initcall(net_dev_init); 6502 6503 static int __init initialize_hashrnd(void) 6504 { 6505 get_random_bytes(&hashrnd, sizeof(hashrnd)); 6506 return 0; 6507 } 6508 6509 late_initcall_sync(initialize_hashrnd); 6510 6511