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, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * 14 * Additional Authors: 15 * Florian la Roche <rzsfl@rz.uni-sb.de> 16 * Alan Cox <gw4pts@gw4pts.ampr.org> 17 * David Hinds <dahinds@users.sourceforge.net> 18 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 19 * Adam Sulmicki <adam@cfar.umd.edu> 20 * Pekka Riikonen <priikone@poesidon.pspt.fi> 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 void dev_base_seq_inc(struct net *net) 203 { 204 while (++net->dev_base_seq == 0); 205 } 206 207 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 208 { 209 unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ)); 210 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 211 } 212 213 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 214 { 215 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 216 } 217 218 static inline void rps_lock(struct softnet_data *sd) 219 { 220 #ifdef CONFIG_RPS 221 spin_lock(&sd->input_pkt_queue.lock); 222 #endif 223 } 224 225 static inline void rps_unlock(struct softnet_data *sd) 226 { 227 #ifdef CONFIG_RPS 228 spin_unlock(&sd->input_pkt_queue.lock); 229 #endif 230 } 231 232 /* Device list insertion */ 233 static int list_netdevice(struct net_device *dev) 234 { 235 struct net *net = dev_net(dev); 236 237 ASSERT_RTNL(); 238 239 write_lock_bh(&dev_base_lock); 240 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 241 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 242 hlist_add_head_rcu(&dev->index_hlist, 243 dev_index_hash(net, dev->ifindex)); 244 write_unlock_bh(&dev_base_lock); 245 246 dev_base_seq_inc(net); 247 248 return 0; 249 } 250 251 /* Device list removal 252 * caller must respect a RCU grace period before freeing/reusing dev 253 */ 254 static void unlist_netdevice(struct net_device *dev) 255 { 256 ASSERT_RTNL(); 257 258 /* Unlink dev from the device chain */ 259 write_lock_bh(&dev_base_lock); 260 list_del_rcu(&dev->dev_list); 261 hlist_del_rcu(&dev->name_hlist); 262 hlist_del_rcu(&dev->index_hlist); 263 write_unlock_bh(&dev_base_lock); 264 265 dev_base_seq_inc(dev_net(dev)); 266 } 267 268 /* 269 * Our notifier list 270 */ 271 272 static RAW_NOTIFIER_HEAD(netdev_chain); 273 274 /* 275 * Device drivers call our routines to queue packets here. We empty the 276 * queue in the local softnet handler. 277 */ 278 279 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 280 EXPORT_PER_CPU_SYMBOL(softnet_data); 281 282 #ifdef CONFIG_LOCKDEP 283 /* 284 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 285 * according to dev->type 286 */ 287 static const unsigned short netdev_lock_type[] = 288 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 289 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 290 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 291 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 292 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 293 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 294 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 295 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 296 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 297 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 298 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 299 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 300 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211, 301 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, 302 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154, 303 ARPHRD_VOID, ARPHRD_NONE}; 304 305 static const char *const netdev_lock_name[] = 306 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 307 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 308 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 309 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 310 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 311 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 312 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 313 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 314 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 315 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 316 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 317 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 318 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211", 319 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", 320 "_xmit_PHONET_PIPE", "_xmit_IEEE802154", 321 "_xmit_VOID", "_xmit_NONE"}; 322 323 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 324 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 325 326 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 327 { 328 int i; 329 330 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 331 if (netdev_lock_type[i] == dev_type) 332 return i; 333 /* the last key is used by default */ 334 return ARRAY_SIZE(netdev_lock_type) - 1; 335 } 336 337 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 338 unsigned short dev_type) 339 { 340 int i; 341 342 i = netdev_lock_pos(dev_type); 343 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 344 netdev_lock_name[i]); 345 } 346 347 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 348 { 349 int i; 350 351 i = netdev_lock_pos(dev->type); 352 lockdep_set_class_and_name(&dev->addr_list_lock, 353 &netdev_addr_lock_key[i], 354 netdev_lock_name[i]); 355 } 356 #else 357 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 358 unsigned short dev_type) 359 { 360 } 361 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 362 { 363 } 364 #endif 365 366 /******************************************************************************* 367 368 Protocol management and registration routines 369 370 *******************************************************************************/ 371 372 /* 373 * Add a protocol ID to the list. Now that the input handler is 374 * smarter we can dispense with all the messy stuff that used to be 375 * here. 376 * 377 * BEWARE!!! Protocol handlers, mangling input packets, 378 * MUST BE last in hash buckets and checking protocol handlers 379 * MUST start from promiscuous ptype_all chain in net_bh. 380 * It is true now, do not change it. 381 * Explanation follows: if protocol handler, mangling packet, will 382 * be the first on list, it is not able to sense, that packet 383 * is cloned and should be copied-on-write, so that it will 384 * change it and subsequent readers will get broken packet. 385 * --ANK (980803) 386 */ 387 388 static inline struct list_head *ptype_head(const struct packet_type *pt) 389 { 390 if (pt->type == htons(ETH_P_ALL)) 391 return &ptype_all; 392 else 393 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 394 } 395 396 /** 397 * dev_add_pack - add packet handler 398 * @pt: packet type declaration 399 * 400 * Add a protocol handler to the networking stack. The passed &packet_type 401 * is linked into kernel lists and may not be freed until it has been 402 * removed from the kernel lists. 403 * 404 * This call does not sleep therefore it can not 405 * guarantee all CPU's that are in middle of receiving packets 406 * will see the new packet type (until the next received packet). 407 */ 408 409 void dev_add_pack(struct packet_type *pt) 410 { 411 struct list_head *head = ptype_head(pt); 412 413 spin_lock(&ptype_lock); 414 list_add_rcu(&pt->list, head); 415 spin_unlock(&ptype_lock); 416 } 417 EXPORT_SYMBOL(dev_add_pack); 418 419 /** 420 * __dev_remove_pack - remove packet handler 421 * @pt: packet type declaration 422 * 423 * Remove a protocol handler that was previously added to the kernel 424 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 425 * from the kernel lists and can be freed or reused once this function 426 * returns. 427 * 428 * The packet type might still be in use by receivers 429 * and must not be freed until after all the CPU's have gone 430 * through a quiescent state. 431 */ 432 void __dev_remove_pack(struct packet_type *pt) 433 { 434 struct list_head *head = ptype_head(pt); 435 struct packet_type *pt1; 436 437 spin_lock(&ptype_lock); 438 439 list_for_each_entry(pt1, head, list) { 440 if (pt == pt1) { 441 list_del_rcu(&pt->list); 442 goto out; 443 } 444 } 445 446 printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt); 447 out: 448 spin_unlock(&ptype_lock); 449 } 450 EXPORT_SYMBOL(__dev_remove_pack); 451 452 /** 453 * dev_remove_pack - remove packet handler 454 * @pt: packet type declaration 455 * 456 * Remove a protocol handler that was previously added to the kernel 457 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 458 * from the kernel lists and can be freed or reused once this function 459 * returns. 460 * 461 * This call sleeps to guarantee that no CPU is looking at the packet 462 * type after return. 463 */ 464 void dev_remove_pack(struct packet_type *pt) 465 { 466 __dev_remove_pack(pt); 467 468 synchronize_net(); 469 } 470 EXPORT_SYMBOL(dev_remove_pack); 471 472 /****************************************************************************** 473 474 Device Boot-time Settings Routines 475 476 *******************************************************************************/ 477 478 /* Boot time configuration table */ 479 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; 480 481 /** 482 * netdev_boot_setup_add - add new setup entry 483 * @name: name of the device 484 * @map: configured settings for the device 485 * 486 * Adds new setup entry to the dev_boot_setup list. The function 487 * returns 0 on error and 1 on success. This is a generic routine to 488 * all netdevices. 489 */ 490 static int netdev_boot_setup_add(char *name, struct ifmap *map) 491 { 492 struct netdev_boot_setup *s; 493 int i; 494 495 s = dev_boot_setup; 496 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 497 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { 498 memset(s[i].name, 0, sizeof(s[i].name)); 499 strlcpy(s[i].name, name, IFNAMSIZ); 500 memcpy(&s[i].map, map, sizeof(s[i].map)); 501 break; 502 } 503 } 504 505 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; 506 } 507 508 /** 509 * netdev_boot_setup_check - check boot time settings 510 * @dev: the netdevice 511 * 512 * Check boot time settings for the device. 513 * The found settings are set for the device to be used 514 * later in the device probing. 515 * Returns 0 if no settings found, 1 if they are. 516 */ 517 int netdev_boot_setup_check(struct net_device *dev) 518 { 519 struct netdev_boot_setup *s = dev_boot_setup; 520 int i; 521 522 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 523 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && 524 !strcmp(dev->name, s[i].name)) { 525 dev->irq = s[i].map.irq; 526 dev->base_addr = s[i].map.base_addr; 527 dev->mem_start = s[i].map.mem_start; 528 dev->mem_end = s[i].map.mem_end; 529 return 1; 530 } 531 } 532 return 0; 533 } 534 EXPORT_SYMBOL(netdev_boot_setup_check); 535 536 537 /** 538 * netdev_boot_base - get address from boot time settings 539 * @prefix: prefix for network device 540 * @unit: id for network device 541 * 542 * Check boot time settings for the base address of device. 543 * The found settings are set for the device to be used 544 * later in the device probing. 545 * Returns 0 if no settings found. 546 */ 547 unsigned long netdev_boot_base(const char *prefix, int unit) 548 { 549 const struct netdev_boot_setup *s = dev_boot_setup; 550 char name[IFNAMSIZ]; 551 int i; 552 553 sprintf(name, "%s%d", prefix, unit); 554 555 /* 556 * If device already registered then return base of 1 557 * to indicate not to probe for this interface 558 */ 559 if (__dev_get_by_name(&init_net, name)) 560 return 1; 561 562 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) 563 if (!strcmp(name, s[i].name)) 564 return s[i].map.base_addr; 565 return 0; 566 } 567 568 /* 569 * Saves at boot time configured settings for any netdevice. 570 */ 571 int __init netdev_boot_setup(char *str) 572 { 573 int ints[5]; 574 struct ifmap map; 575 576 str = get_options(str, ARRAY_SIZE(ints), ints); 577 if (!str || !*str) 578 return 0; 579 580 /* Save settings */ 581 memset(&map, 0, sizeof(map)); 582 if (ints[0] > 0) 583 map.irq = ints[1]; 584 if (ints[0] > 1) 585 map.base_addr = ints[2]; 586 if (ints[0] > 2) 587 map.mem_start = ints[3]; 588 if (ints[0] > 3) 589 map.mem_end = ints[4]; 590 591 /* Add new entry to the list */ 592 return netdev_boot_setup_add(str, &map); 593 } 594 595 __setup("netdev=", netdev_boot_setup); 596 597 /******************************************************************************* 598 599 Device Interface Subroutines 600 601 *******************************************************************************/ 602 603 /** 604 * __dev_get_by_name - find a device by its name 605 * @net: the applicable net namespace 606 * @name: name to find 607 * 608 * Find an interface by name. Must be called under RTNL semaphore 609 * or @dev_base_lock. If the name is found a pointer to the device 610 * is returned. If the name is not found then %NULL is returned. The 611 * reference counters are not incremented so the caller must be 612 * careful with locks. 613 */ 614 615 struct net_device *__dev_get_by_name(struct net *net, const char *name) 616 { 617 struct hlist_node *p; 618 struct net_device *dev; 619 struct hlist_head *head = dev_name_hash(net, name); 620 621 hlist_for_each_entry(dev, p, head, name_hlist) 622 if (!strncmp(dev->name, name, IFNAMSIZ)) 623 return dev; 624 625 return NULL; 626 } 627 EXPORT_SYMBOL(__dev_get_by_name); 628 629 /** 630 * dev_get_by_name_rcu - find a device by its name 631 * @net: the applicable net namespace 632 * @name: name to find 633 * 634 * Find an interface by name. 635 * If the name is found a pointer to the device is returned. 636 * If the name is not found then %NULL is returned. 637 * The reference counters are not incremented so the caller must be 638 * careful with locks. The caller must hold RCU lock. 639 */ 640 641 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 642 { 643 struct hlist_node *p; 644 struct net_device *dev; 645 struct hlist_head *head = dev_name_hash(net, name); 646 647 hlist_for_each_entry_rcu(dev, p, head, name_hlist) 648 if (!strncmp(dev->name, name, IFNAMSIZ)) 649 return dev; 650 651 return NULL; 652 } 653 EXPORT_SYMBOL(dev_get_by_name_rcu); 654 655 /** 656 * dev_get_by_name - find a device by its name 657 * @net: the applicable net namespace 658 * @name: name to find 659 * 660 * Find an interface by name. This can be called from any 661 * context and does its own locking. The returned handle has 662 * the usage count incremented and the caller must use dev_put() to 663 * release it when it is no longer needed. %NULL is returned if no 664 * matching device is found. 665 */ 666 667 struct net_device *dev_get_by_name(struct net *net, const char *name) 668 { 669 struct net_device *dev; 670 671 rcu_read_lock(); 672 dev = dev_get_by_name_rcu(net, name); 673 if (dev) 674 dev_hold(dev); 675 rcu_read_unlock(); 676 return dev; 677 } 678 EXPORT_SYMBOL(dev_get_by_name); 679 680 /** 681 * __dev_get_by_index - find a device by its ifindex 682 * @net: the applicable net namespace 683 * @ifindex: index of device 684 * 685 * Search for an interface by index. Returns %NULL if the device 686 * is not found or a pointer to the device. The device has not 687 * had its reference counter increased so the caller must be careful 688 * about locking. The caller must hold either the RTNL semaphore 689 * or @dev_base_lock. 690 */ 691 692 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 693 { 694 struct hlist_node *p; 695 struct net_device *dev; 696 struct hlist_head *head = dev_index_hash(net, ifindex); 697 698 hlist_for_each_entry(dev, p, head, index_hlist) 699 if (dev->ifindex == ifindex) 700 return dev; 701 702 return NULL; 703 } 704 EXPORT_SYMBOL(__dev_get_by_index); 705 706 /** 707 * dev_get_by_index_rcu - find a device by its ifindex 708 * @net: the applicable net namespace 709 * @ifindex: index of device 710 * 711 * Search for an interface by index. Returns %NULL if the device 712 * is not found or a pointer to the device. The device has not 713 * had its reference counter increased so the caller must be careful 714 * about locking. The caller must hold RCU lock. 715 */ 716 717 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 718 { 719 struct hlist_node *p; 720 struct net_device *dev; 721 struct hlist_head *head = dev_index_hash(net, ifindex); 722 723 hlist_for_each_entry_rcu(dev, p, head, index_hlist) 724 if (dev->ifindex == ifindex) 725 return dev; 726 727 return NULL; 728 } 729 EXPORT_SYMBOL(dev_get_by_index_rcu); 730 731 732 /** 733 * dev_get_by_index - find a device by its ifindex 734 * @net: the applicable net namespace 735 * @ifindex: index of device 736 * 737 * Search for an interface by index. Returns NULL if the device 738 * is not found or a pointer to the device. The device returned has 739 * had a reference added and the pointer is safe until the user calls 740 * dev_put to indicate they have finished with it. 741 */ 742 743 struct net_device *dev_get_by_index(struct net *net, int ifindex) 744 { 745 struct net_device *dev; 746 747 rcu_read_lock(); 748 dev = dev_get_by_index_rcu(net, ifindex); 749 if (dev) 750 dev_hold(dev); 751 rcu_read_unlock(); 752 return dev; 753 } 754 EXPORT_SYMBOL(dev_get_by_index); 755 756 /** 757 * dev_getbyhwaddr_rcu - find a device by its hardware address 758 * @net: the applicable net namespace 759 * @type: media type of device 760 * @ha: hardware address 761 * 762 * Search for an interface by MAC address. Returns NULL if the device 763 * is not found or a pointer to the device. 764 * The caller must hold RCU or RTNL. 765 * The returned device has not had its ref count increased 766 * and the caller must therefore be careful about locking 767 * 768 */ 769 770 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 771 const char *ha) 772 { 773 struct net_device *dev; 774 775 for_each_netdev_rcu(net, dev) 776 if (dev->type == type && 777 !memcmp(dev->dev_addr, ha, dev->addr_len)) 778 return dev; 779 780 return NULL; 781 } 782 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 783 784 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type) 785 { 786 struct net_device *dev; 787 788 ASSERT_RTNL(); 789 for_each_netdev(net, dev) 790 if (dev->type == type) 791 return dev; 792 793 return NULL; 794 } 795 EXPORT_SYMBOL(__dev_getfirstbyhwtype); 796 797 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 798 { 799 struct net_device *dev, *ret = NULL; 800 801 rcu_read_lock(); 802 for_each_netdev_rcu(net, dev) 803 if (dev->type == type) { 804 dev_hold(dev); 805 ret = dev; 806 break; 807 } 808 rcu_read_unlock(); 809 return ret; 810 } 811 EXPORT_SYMBOL(dev_getfirstbyhwtype); 812 813 /** 814 * dev_get_by_flags_rcu - find any device with given flags 815 * @net: the applicable net namespace 816 * @if_flags: IFF_* values 817 * @mask: bitmask of bits in if_flags to check 818 * 819 * Search for any interface with the given flags. Returns NULL if a device 820 * is not found or a pointer to the device. Must be called inside 821 * rcu_read_lock(), and result refcount is unchanged. 822 */ 823 824 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags, 825 unsigned short mask) 826 { 827 struct net_device *dev, *ret; 828 829 ret = NULL; 830 for_each_netdev_rcu(net, dev) { 831 if (((dev->flags ^ if_flags) & mask) == 0) { 832 ret = dev; 833 break; 834 } 835 } 836 return ret; 837 } 838 EXPORT_SYMBOL(dev_get_by_flags_rcu); 839 840 /** 841 * dev_valid_name - check if name is okay for network device 842 * @name: name string 843 * 844 * Network device names need to be valid file names to 845 * to allow sysfs to work. We also disallow any kind of 846 * whitespace. 847 */ 848 int dev_valid_name(const char *name) 849 { 850 if (*name == '\0') 851 return 0; 852 if (strlen(name) >= IFNAMSIZ) 853 return 0; 854 if (!strcmp(name, ".") || !strcmp(name, "..")) 855 return 0; 856 857 while (*name) { 858 if (*name == '/' || isspace(*name)) 859 return 0; 860 name++; 861 } 862 return 1; 863 } 864 EXPORT_SYMBOL(dev_valid_name); 865 866 /** 867 * __dev_alloc_name - allocate a name for a device 868 * @net: network namespace to allocate the device name in 869 * @name: name format string 870 * @buf: scratch buffer and result name string 871 * 872 * Passed a format string - eg "lt%d" it will try and find a suitable 873 * id. It scans list of devices to build up a free map, then chooses 874 * the first empty slot. The caller must hold the dev_base or rtnl lock 875 * while allocating the name and adding the device in order to avoid 876 * duplicates. 877 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 878 * Returns the number of the unit assigned or a negative errno code. 879 */ 880 881 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 882 { 883 int i = 0; 884 const char *p; 885 const int max_netdevices = 8*PAGE_SIZE; 886 unsigned long *inuse; 887 struct net_device *d; 888 889 p = strnchr(name, IFNAMSIZ-1, '%'); 890 if (p) { 891 /* 892 * Verify the string as this thing may have come from 893 * the user. There must be either one "%d" and no other "%" 894 * characters. 895 */ 896 if (p[1] != 'd' || strchr(p + 2, '%')) 897 return -EINVAL; 898 899 /* Use one page as a bit array of possible slots */ 900 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 901 if (!inuse) 902 return -ENOMEM; 903 904 for_each_netdev(net, d) { 905 if (!sscanf(d->name, name, &i)) 906 continue; 907 if (i < 0 || i >= max_netdevices) 908 continue; 909 910 /* avoid cases where sscanf is not exact inverse of printf */ 911 snprintf(buf, IFNAMSIZ, name, i); 912 if (!strncmp(buf, d->name, IFNAMSIZ)) 913 set_bit(i, inuse); 914 } 915 916 i = find_first_zero_bit(inuse, max_netdevices); 917 free_page((unsigned long) inuse); 918 } 919 920 if (buf != name) 921 snprintf(buf, IFNAMSIZ, name, i); 922 if (!__dev_get_by_name(net, buf)) 923 return i; 924 925 /* It is possible to run out of possible slots 926 * when the name is long and there isn't enough space left 927 * for the digits, or if all bits are used. 928 */ 929 return -ENFILE; 930 } 931 932 /** 933 * dev_alloc_name - allocate a name for a device 934 * @dev: device 935 * @name: name format string 936 * 937 * Passed a format string - eg "lt%d" it will try and find a suitable 938 * id. It scans list of devices to build up a free map, then chooses 939 * the first empty slot. The caller must hold the dev_base or rtnl lock 940 * while allocating the name and adding the device in order to avoid 941 * duplicates. 942 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 943 * Returns the number of the unit assigned or a negative errno code. 944 */ 945 946 int dev_alloc_name(struct net_device *dev, const char *name) 947 { 948 char buf[IFNAMSIZ]; 949 struct net *net; 950 int ret; 951 952 BUG_ON(!dev_net(dev)); 953 net = dev_net(dev); 954 ret = __dev_alloc_name(net, name, buf); 955 if (ret >= 0) 956 strlcpy(dev->name, buf, IFNAMSIZ); 957 return ret; 958 } 959 EXPORT_SYMBOL(dev_alloc_name); 960 961 static int dev_get_valid_name(struct net_device *dev, const char *name) 962 { 963 struct net *net; 964 965 BUG_ON(!dev_net(dev)); 966 net = dev_net(dev); 967 968 if (!dev_valid_name(name)) 969 return -EINVAL; 970 971 if (strchr(name, '%')) 972 return dev_alloc_name(dev, name); 973 else if (__dev_get_by_name(net, name)) 974 return -EEXIST; 975 else if (dev->name != name) 976 strlcpy(dev->name, name, IFNAMSIZ); 977 978 return 0; 979 } 980 981 /** 982 * dev_change_name - change name of a device 983 * @dev: device 984 * @newname: name (or format string) must be at least IFNAMSIZ 985 * 986 * Change name of a device, can pass format strings "eth%d". 987 * for wildcarding. 988 */ 989 int dev_change_name(struct net_device *dev, const char *newname) 990 { 991 char oldname[IFNAMSIZ]; 992 int err = 0; 993 int ret; 994 struct net *net; 995 996 ASSERT_RTNL(); 997 BUG_ON(!dev_net(dev)); 998 999 net = dev_net(dev); 1000 if (dev->flags & IFF_UP) 1001 return -EBUSY; 1002 1003 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) 1004 return 0; 1005 1006 memcpy(oldname, dev->name, IFNAMSIZ); 1007 1008 err = dev_get_valid_name(dev, newname); 1009 if (err < 0) 1010 return err; 1011 1012 rollback: 1013 ret = device_rename(&dev->dev, dev->name); 1014 if (ret) { 1015 memcpy(dev->name, oldname, IFNAMSIZ); 1016 return ret; 1017 } 1018 1019 write_lock_bh(&dev_base_lock); 1020 hlist_del_rcu(&dev->name_hlist); 1021 write_unlock_bh(&dev_base_lock); 1022 1023 synchronize_rcu(); 1024 1025 write_lock_bh(&dev_base_lock); 1026 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 1027 write_unlock_bh(&dev_base_lock); 1028 1029 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1030 ret = notifier_to_errno(ret); 1031 1032 if (ret) { 1033 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1034 if (err >= 0) { 1035 err = ret; 1036 memcpy(dev->name, oldname, IFNAMSIZ); 1037 goto rollback; 1038 } else { 1039 printk(KERN_ERR 1040 "%s: name change rollback failed: %d.\n", 1041 dev->name, ret); 1042 } 1043 } 1044 1045 return err; 1046 } 1047 1048 /** 1049 * dev_set_alias - change ifalias of a device 1050 * @dev: device 1051 * @alias: name up to IFALIASZ 1052 * @len: limit of bytes to copy from info 1053 * 1054 * Set ifalias for a device, 1055 */ 1056 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1057 { 1058 ASSERT_RTNL(); 1059 1060 if (len >= IFALIASZ) 1061 return -EINVAL; 1062 1063 if (!len) { 1064 if (dev->ifalias) { 1065 kfree(dev->ifalias); 1066 dev->ifalias = NULL; 1067 } 1068 return 0; 1069 } 1070 1071 dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL); 1072 if (!dev->ifalias) 1073 return -ENOMEM; 1074 1075 strlcpy(dev->ifalias, alias, len+1); 1076 return len; 1077 } 1078 1079 1080 /** 1081 * netdev_features_change - device changes features 1082 * @dev: device to cause notification 1083 * 1084 * Called to indicate a device has changed features. 1085 */ 1086 void netdev_features_change(struct net_device *dev) 1087 { 1088 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1089 } 1090 EXPORT_SYMBOL(netdev_features_change); 1091 1092 /** 1093 * netdev_state_change - device changes state 1094 * @dev: device to cause notification 1095 * 1096 * Called to indicate a device has changed state. This function calls 1097 * the notifier chains for netdev_chain and sends a NEWLINK message 1098 * to the routing socket. 1099 */ 1100 void netdev_state_change(struct net_device *dev) 1101 { 1102 if (dev->flags & IFF_UP) { 1103 call_netdevice_notifiers(NETDEV_CHANGE, dev); 1104 rtmsg_ifinfo(RTM_NEWLINK, dev, 0); 1105 } 1106 } 1107 EXPORT_SYMBOL(netdev_state_change); 1108 1109 int netdev_bonding_change(struct net_device *dev, unsigned long event) 1110 { 1111 return call_netdevice_notifiers(event, dev); 1112 } 1113 EXPORT_SYMBOL(netdev_bonding_change); 1114 1115 /** 1116 * dev_load - load a network module 1117 * @net: the applicable net namespace 1118 * @name: name of interface 1119 * 1120 * If a network interface is not present and the process has suitable 1121 * privileges this function loads the module. If module loading is not 1122 * available in this kernel then it becomes a nop. 1123 */ 1124 1125 void dev_load(struct net *net, const char *name) 1126 { 1127 struct net_device *dev; 1128 int no_module; 1129 1130 rcu_read_lock(); 1131 dev = dev_get_by_name_rcu(net, name); 1132 rcu_read_unlock(); 1133 1134 no_module = !dev; 1135 if (no_module && capable(CAP_NET_ADMIN)) 1136 no_module = request_module("netdev-%s", name); 1137 if (no_module && capable(CAP_SYS_MODULE)) { 1138 if (!request_module("%s", name)) 1139 pr_err("Loading kernel module for a network device " 1140 "with CAP_SYS_MODULE (deprecated). Use CAP_NET_ADMIN and alias netdev-%s " 1141 "instead\n", name); 1142 } 1143 } 1144 EXPORT_SYMBOL(dev_load); 1145 1146 static int __dev_open(struct net_device *dev) 1147 { 1148 const struct net_device_ops *ops = dev->netdev_ops; 1149 int ret; 1150 1151 ASSERT_RTNL(); 1152 1153 if (!netif_device_present(dev)) 1154 return -ENODEV; 1155 1156 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev); 1157 ret = notifier_to_errno(ret); 1158 if (ret) 1159 return ret; 1160 1161 set_bit(__LINK_STATE_START, &dev->state); 1162 1163 if (ops->ndo_validate_addr) 1164 ret = ops->ndo_validate_addr(dev); 1165 1166 if (!ret && ops->ndo_open) 1167 ret = ops->ndo_open(dev); 1168 1169 if (ret) 1170 clear_bit(__LINK_STATE_START, &dev->state); 1171 else { 1172 dev->flags |= IFF_UP; 1173 net_dmaengine_get(); 1174 dev_set_rx_mode(dev); 1175 dev_activate(dev); 1176 } 1177 1178 return ret; 1179 } 1180 1181 /** 1182 * dev_open - prepare an interface for use. 1183 * @dev: device to open 1184 * 1185 * Takes a device from down to up state. The device's private open 1186 * function is invoked and then the multicast lists are loaded. Finally 1187 * the device is moved into the up state and a %NETDEV_UP message is 1188 * sent to the netdev notifier chain. 1189 * 1190 * Calling this function on an active interface is a nop. On a failure 1191 * a negative errno code is returned. 1192 */ 1193 int dev_open(struct net_device *dev) 1194 { 1195 int ret; 1196 1197 if (dev->flags & IFF_UP) 1198 return 0; 1199 1200 ret = __dev_open(dev); 1201 if (ret < 0) 1202 return ret; 1203 1204 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1205 call_netdevice_notifiers(NETDEV_UP, dev); 1206 1207 return ret; 1208 } 1209 EXPORT_SYMBOL(dev_open); 1210 1211 static int __dev_close_many(struct list_head *head) 1212 { 1213 struct net_device *dev; 1214 1215 ASSERT_RTNL(); 1216 might_sleep(); 1217 1218 list_for_each_entry(dev, head, unreg_list) { 1219 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1220 1221 clear_bit(__LINK_STATE_START, &dev->state); 1222 1223 /* Synchronize to scheduled poll. We cannot touch poll list, it 1224 * can be even on different cpu. So just clear netif_running(). 1225 * 1226 * dev->stop() will invoke napi_disable() on all of it's 1227 * napi_struct instances on this device. 1228 */ 1229 smp_mb__after_clear_bit(); /* Commit netif_running(). */ 1230 } 1231 1232 dev_deactivate_many(head); 1233 1234 list_for_each_entry(dev, head, unreg_list) { 1235 const struct net_device_ops *ops = dev->netdev_ops; 1236 1237 /* 1238 * Call the device specific close. This cannot fail. 1239 * Only if device is UP 1240 * 1241 * We allow it to be called even after a DETACH hot-plug 1242 * event. 1243 */ 1244 if (ops->ndo_stop) 1245 ops->ndo_stop(dev); 1246 1247 dev->flags &= ~IFF_UP; 1248 net_dmaengine_put(); 1249 } 1250 1251 return 0; 1252 } 1253 1254 static int __dev_close(struct net_device *dev) 1255 { 1256 int retval; 1257 LIST_HEAD(single); 1258 1259 list_add(&dev->unreg_list, &single); 1260 retval = __dev_close_many(&single); 1261 list_del(&single); 1262 return retval; 1263 } 1264 1265 static int dev_close_many(struct list_head *head) 1266 { 1267 struct net_device *dev, *tmp; 1268 LIST_HEAD(tmp_list); 1269 1270 list_for_each_entry_safe(dev, tmp, head, unreg_list) 1271 if (!(dev->flags & IFF_UP)) 1272 list_move(&dev->unreg_list, &tmp_list); 1273 1274 __dev_close_many(head); 1275 1276 list_for_each_entry(dev, head, unreg_list) { 1277 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1278 call_netdevice_notifiers(NETDEV_DOWN, dev); 1279 } 1280 1281 /* rollback_registered_many needs the complete original list */ 1282 list_splice(&tmp_list, head); 1283 return 0; 1284 } 1285 1286 /** 1287 * dev_close - shutdown an interface. 1288 * @dev: device to shutdown 1289 * 1290 * This function moves an active device into down state. A 1291 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1292 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1293 * chain. 1294 */ 1295 int dev_close(struct net_device *dev) 1296 { 1297 if (dev->flags & IFF_UP) { 1298 LIST_HEAD(single); 1299 1300 list_add(&dev->unreg_list, &single); 1301 dev_close_many(&single); 1302 list_del(&single); 1303 } 1304 return 0; 1305 } 1306 EXPORT_SYMBOL(dev_close); 1307 1308 1309 /** 1310 * dev_disable_lro - disable Large Receive Offload on a device 1311 * @dev: device 1312 * 1313 * Disable Large Receive Offload (LRO) on a net device. Must be 1314 * called under RTNL. This is needed if received packets may be 1315 * forwarded to another interface. 1316 */ 1317 void dev_disable_lro(struct net_device *dev) 1318 { 1319 u32 flags; 1320 1321 /* 1322 * If we're trying to disable lro on a vlan device 1323 * use the underlying physical device instead 1324 */ 1325 if (is_vlan_dev(dev)) 1326 dev = vlan_dev_real_dev(dev); 1327 1328 if (dev->ethtool_ops && dev->ethtool_ops->get_flags) 1329 flags = dev->ethtool_ops->get_flags(dev); 1330 else 1331 flags = ethtool_op_get_flags(dev); 1332 1333 if (!(flags & ETH_FLAG_LRO)) 1334 return; 1335 1336 __ethtool_set_flags(dev, flags & ~ETH_FLAG_LRO); 1337 if (unlikely(dev->features & NETIF_F_LRO)) 1338 netdev_WARN(dev, "failed to disable LRO!\n"); 1339 } 1340 EXPORT_SYMBOL(dev_disable_lro); 1341 1342 1343 static int dev_boot_phase = 1; 1344 1345 /** 1346 * register_netdevice_notifier - register a network notifier block 1347 * @nb: notifier 1348 * 1349 * Register a notifier to be called when network device events occur. 1350 * The notifier passed is linked into the kernel structures and must 1351 * not be reused until it has been unregistered. A negative errno code 1352 * is returned on a failure. 1353 * 1354 * When registered all registration and up events are replayed 1355 * to the new notifier to allow device to have a race free 1356 * view of the network device list. 1357 */ 1358 1359 int register_netdevice_notifier(struct notifier_block *nb) 1360 { 1361 struct net_device *dev; 1362 struct net_device *last; 1363 struct net *net; 1364 int err; 1365 1366 rtnl_lock(); 1367 err = raw_notifier_chain_register(&netdev_chain, nb); 1368 if (err) 1369 goto unlock; 1370 if (dev_boot_phase) 1371 goto unlock; 1372 for_each_net(net) { 1373 for_each_netdev(net, dev) { 1374 err = nb->notifier_call(nb, NETDEV_REGISTER, dev); 1375 err = notifier_to_errno(err); 1376 if (err) 1377 goto rollback; 1378 1379 if (!(dev->flags & IFF_UP)) 1380 continue; 1381 1382 nb->notifier_call(nb, NETDEV_UP, dev); 1383 } 1384 } 1385 1386 unlock: 1387 rtnl_unlock(); 1388 return err; 1389 1390 rollback: 1391 last = dev; 1392 for_each_net(net) { 1393 for_each_netdev(net, dev) { 1394 if (dev == last) 1395 break; 1396 1397 if (dev->flags & IFF_UP) { 1398 nb->notifier_call(nb, NETDEV_GOING_DOWN, dev); 1399 nb->notifier_call(nb, NETDEV_DOWN, dev); 1400 } 1401 nb->notifier_call(nb, NETDEV_UNREGISTER, dev); 1402 nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev); 1403 } 1404 } 1405 1406 raw_notifier_chain_unregister(&netdev_chain, nb); 1407 goto unlock; 1408 } 1409 EXPORT_SYMBOL(register_netdevice_notifier); 1410 1411 /** 1412 * unregister_netdevice_notifier - unregister a network notifier block 1413 * @nb: notifier 1414 * 1415 * Unregister a notifier previously registered by 1416 * register_netdevice_notifier(). The notifier is unlinked into the 1417 * kernel structures and may then be reused. A negative errno code 1418 * is returned on a failure. 1419 */ 1420 1421 int unregister_netdevice_notifier(struct notifier_block *nb) 1422 { 1423 int err; 1424 1425 rtnl_lock(); 1426 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1427 rtnl_unlock(); 1428 return err; 1429 } 1430 EXPORT_SYMBOL(unregister_netdevice_notifier); 1431 1432 /** 1433 * call_netdevice_notifiers - call all network notifier blocks 1434 * @val: value passed unmodified to notifier function 1435 * @dev: net_device pointer passed unmodified to notifier function 1436 * 1437 * Call all network notifier blocks. Parameters and return value 1438 * are as for raw_notifier_call_chain(). 1439 */ 1440 1441 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1442 { 1443 ASSERT_RTNL(); 1444 return raw_notifier_call_chain(&netdev_chain, val, dev); 1445 } 1446 EXPORT_SYMBOL(call_netdevice_notifiers); 1447 1448 /* When > 0 there are consumers of rx skb time stamps */ 1449 static atomic_t netstamp_needed = ATOMIC_INIT(0); 1450 1451 void net_enable_timestamp(void) 1452 { 1453 atomic_inc(&netstamp_needed); 1454 } 1455 EXPORT_SYMBOL(net_enable_timestamp); 1456 1457 void net_disable_timestamp(void) 1458 { 1459 atomic_dec(&netstamp_needed); 1460 } 1461 EXPORT_SYMBOL(net_disable_timestamp); 1462 1463 static inline void net_timestamp_set(struct sk_buff *skb) 1464 { 1465 if (atomic_read(&netstamp_needed)) 1466 __net_timestamp(skb); 1467 else 1468 skb->tstamp.tv64 = 0; 1469 } 1470 1471 static inline void net_timestamp_check(struct sk_buff *skb) 1472 { 1473 if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed)) 1474 __net_timestamp(skb); 1475 } 1476 1477 static inline bool is_skb_forwardable(struct net_device *dev, 1478 struct sk_buff *skb) 1479 { 1480 unsigned int len; 1481 1482 if (!(dev->flags & IFF_UP)) 1483 return false; 1484 1485 len = dev->mtu + dev->hard_header_len + VLAN_HLEN; 1486 if (skb->len <= len) 1487 return true; 1488 1489 /* if TSO is enabled, we don't care about the length as the packet 1490 * could be forwarded without being segmented before 1491 */ 1492 if (skb_is_gso(skb)) 1493 return true; 1494 1495 return false; 1496 } 1497 1498 /** 1499 * dev_forward_skb - loopback an skb to another netif 1500 * 1501 * @dev: destination network device 1502 * @skb: buffer to forward 1503 * 1504 * return values: 1505 * NET_RX_SUCCESS (no congestion) 1506 * NET_RX_DROP (packet was dropped, but freed) 1507 * 1508 * dev_forward_skb can be used for injecting an skb from the 1509 * start_xmit function of one device into the receive queue 1510 * of another device. 1511 * 1512 * The receiving device may be in another namespace, so 1513 * we have to clear all information in the skb that could 1514 * impact namespace isolation. 1515 */ 1516 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 1517 { 1518 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) { 1519 if (skb_copy_ubufs(skb, GFP_ATOMIC)) { 1520 atomic_long_inc(&dev->rx_dropped); 1521 kfree_skb(skb); 1522 return NET_RX_DROP; 1523 } 1524 } 1525 1526 skb_orphan(skb); 1527 nf_reset(skb); 1528 1529 if (unlikely(!is_skb_forwardable(dev, skb))) { 1530 atomic_long_inc(&dev->rx_dropped); 1531 kfree_skb(skb); 1532 return NET_RX_DROP; 1533 } 1534 skb_set_dev(skb, dev); 1535 skb->tstamp.tv64 = 0; 1536 skb->pkt_type = PACKET_HOST; 1537 skb->protocol = eth_type_trans(skb, dev); 1538 return netif_rx(skb); 1539 } 1540 EXPORT_SYMBOL_GPL(dev_forward_skb); 1541 1542 static inline int deliver_skb(struct sk_buff *skb, 1543 struct packet_type *pt_prev, 1544 struct net_device *orig_dev) 1545 { 1546 atomic_inc(&skb->users); 1547 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1548 } 1549 1550 /* 1551 * Support routine. Sends outgoing frames to any network 1552 * taps currently in use. 1553 */ 1554 1555 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 1556 { 1557 struct packet_type *ptype; 1558 struct sk_buff *skb2 = NULL; 1559 struct packet_type *pt_prev = NULL; 1560 1561 rcu_read_lock(); 1562 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1563 /* Never send packets back to the socket 1564 * they originated from - MvS (miquels@drinkel.ow.org) 1565 */ 1566 if ((ptype->dev == dev || !ptype->dev) && 1567 (ptype->af_packet_priv == NULL || 1568 (struct sock *)ptype->af_packet_priv != skb->sk)) { 1569 if (pt_prev) { 1570 deliver_skb(skb2, pt_prev, skb->dev); 1571 pt_prev = ptype; 1572 continue; 1573 } 1574 1575 skb2 = skb_clone(skb, GFP_ATOMIC); 1576 if (!skb2) 1577 break; 1578 1579 net_timestamp_set(skb2); 1580 1581 /* skb->nh should be correctly 1582 set by sender, so that the second statement is 1583 just protection against buggy protocols. 1584 */ 1585 skb_reset_mac_header(skb2); 1586 1587 if (skb_network_header(skb2) < skb2->data || 1588 skb2->network_header > skb2->tail) { 1589 if (net_ratelimit()) 1590 printk(KERN_CRIT "protocol %04x is " 1591 "buggy, dev %s\n", 1592 ntohs(skb2->protocol), 1593 dev->name); 1594 skb_reset_network_header(skb2); 1595 } 1596 1597 skb2->transport_header = skb2->network_header; 1598 skb2->pkt_type = PACKET_OUTGOING; 1599 pt_prev = ptype; 1600 } 1601 } 1602 if (pt_prev) 1603 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 1604 rcu_read_unlock(); 1605 } 1606 1607 /* netif_setup_tc - Handle tc mappings on real_num_tx_queues change 1608 * @dev: Network device 1609 * @txq: number of queues available 1610 * 1611 * If real_num_tx_queues is changed the tc mappings may no longer be 1612 * valid. To resolve this verify the tc mapping remains valid and if 1613 * not NULL the mapping. With no priorities mapping to this 1614 * offset/count pair it will no longer be used. In the worst case TC0 1615 * is invalid nothing can be done so disable priority mappings. If is 1616 * expected that drivers will fix this mapping if they can before 1617 * calling netif_set_real_num_tx_queues. 1618 */ 1619 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 1620 { 1621 int i; 1622 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 1623 1624 /* If TC0 is invalidated disable TC mapping */ 1625 if (tc->offset + tc->count > txq) { 1626 pr_warning("Number of in use tx queues changed " 1627 "invalidating tc mappings. Priority " 1628 "traffic classification disabled!\n"); 1629 dev->num_tc = 0; 1630 return; 1631 } 1632 1633 /* Invalidated prio to tc mappings set to TC0 */ 1634 for (i = 1; i < TC_BITMASK + 1; i++) { 1635 int q = netdev_get_prio_tc_map(dev, i); 1636 1637 tc = &dev->tc_to_txq[q]; 1638 if (tc->offset + tc->count > txq) { 1639 pr_warning("Number of in use tx queues " 1640 "changed. Priority %i to tc " 1641 "mapping %i is no longer valid " 1642 "setting map to 0\n", 1643 i, q); 1644 netdev_set_prio_tc_map(dev, i, 0); 1645 } 1646 } 1647 } 1648 1649 /* 1650 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 1651 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed. 1652 */ 1653 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 1654 { 1655 int rc; 1656 1657 if (txq < 1 || txq > dev->num_tx_queues) 1658 return -EINVAL; 1659 1660 if (dev->reg_state == NETREG_REGISTERED || 1661 dev->reg_state == NETREG_UNREGISTERING) { 1662 ASSERT_RTNL(); 1663 1664 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 1665 txq); 1666 if (rc) 1667 return rc; 1668 1669 if (dev->num_tc) 1670 netif_setup_tc(dev, txq); 1671 1672 if (txq < dev->real_num_tx_queues) 1673 qdisc_reset_all_tx_gt(dev, txq); 1674 } 1675 1676 dev->real_num_tx_queues = txq; 1677 return 0; 1678 } 1679 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 1680 1681 #ifdef CONFIG_RPS 1682 /** 1683 * netif_set_real_num_rx_queues - set actual number of RX queues used 1684 * @dev: Network device 1685 * @rxq: Actual number of RX queues 1686 * 1687 * This must be called either with the rtnl_lock held or before 1688 * registration of the net device. Returns 0 on success, or a 1689 * negative error code. If called before registration, it always 1690 * succeeds. 1691 */ 1692 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 1693 { 1694 int rc; 1695 1696 if (rxq < 1 || rxq > dev->num_rx_queues) 1697 return -EINVAL; 1698 1699 if (dev->reg_state == NETREG_REGISTERED) { 1700 ASSERT_RTNL(); 1701 1702 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 1703 rxq); 1704 if (rc) 1705 return rc; 1706 } 1707 1708 dev->real_num_rx_queues = rxq; 1709 return 0; 1710 } 1711 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 1712 #endif 1713 1714 static inline void __netif_reschedule(struct Qdisc *q) 1715 { 1716 struct softnet_data *sd; 1717 unsigned long flags; 1718 1719 local_irq_save(flags); 1720 sd = &__get_cpu_var(softnet_data); 1721 q->next_sched = NULL; 1722 *sd->output_queue_tailp = q; 1723 sd->output_queue_tailp = &q->next_sched; 1724 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1725 local_irq_restore(flags); 1726 } 1727 1728 void __netif_schedule(struct Qdisc *q) 1729 { 1730 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 1731 __netif_reschedule(q); 1732 } 1733 EXPORT_SYMBOL(__netif_schedule); 1734 1735 void dev_kfree_skb_irq(struct sk_buff *skb) 1736 { 1737 if (atomic_dec_and_test(&skb->users)) { 1738 struct softnet_data *sd; 1739 unsigned long flags; 1740 1741 local_irq_save(flags); 1742 sd = &__get_cpu_var(softnet_data); 1743 skb->next = sd->completion_queue; 1744 sd->completion_queue = skb; 1745 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1746 local_irq_restore(flags); 1747 } 1748 } 1749 EXPORT_SYMBOL(dev_kfree_skb_irq); 1750 1751 void dev_kfree_skb_any(struct sk_buff *skb) 1752 { 1753 if (in_irq() || irqs_disabled()) 1754 dev_kfree_skb_irq(skb); 1755 else 1756 dev_kfree_skb(skb); 1757 } 1758 EXPORT_SYMBOL(dev_kfree_skb_any); 1759 1760 1761 /** 1762 * netif_device_detach - mark device as removed 1763 * @dev: network device 1764 * 1765 * Mark device as removed from system and therefore no longer available. 1766 */ 1767 void netif_device_detach(struct net_device *dev) 1768 { 1769 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 1770 netif_running(dev)) { 1771 netif_tx_stop_all_queues(dev); 1772 } 1773 } 1774 EXPORT_SYMBOL(netif_device_detach); 1775 1776 /** 1777 * netif_device_attach - mark device as attached 1778 * @dev: network device 1779 * 1780 * Mark device as attached from system and restart if needed. 1781 */ 1782 void netif_device_attach(struct net_device *dev) 1783 { 1784 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 1785 netif_running(dev)) { 1786 netif_tx_wake_all_queues(dev); 1787 __netdev_watchdog_up(dev); 1788 } 1789 } 1790 EXPORT_SYMBOL(netif_device_attach); 1791 1792 /** 1793 * skb_dev_set -- assign a new device to a buffer 1794 * @skb: buffer for the new device 1795 * @dev: network device 1796 * 1797 * If an skb is owned by a device already, we have to reset 1798 * all data private to the namespace a device belongs to 1799 * before assigning it a new device. 1800 */ 1801 #ifdef CONFIG_NET_NS 1802 void skb_set_dev(struct sk_buff *skb, struct net_device *dev) 1803 { 1804 skb_dst_drop(skb); 1805 if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) { 1806 secpath_reset(skb); 1807 nf_reset(skb); 1808 skb_init_secmark(skb); 1809 skb->mark = 0; 1810 skb->priority = 0; 1811 skb->nf_trace = 0; 1812 skb->ipvs_property = 0; 1813 #ifdef CONFIG_NET_SCHED 1814 skb->tc_index = 0; 1815 #endif 1816 } 1817 skb->dev = dev; 1818 } 1819 EXPORT_SYMBOL(skb_set_dev); 1820 #endif /* CONFIG_NET_NS */ 1821 1822 /* 1823 * Invalidate hardware checksum when packet is to be mangled, and 1824 * complete checksum manually on outgoing path. 1825 */ 1826 int skb_checksum_help(struct sk_buff *skb) 1827 { 1828 __wsum csum; 1829 int ret = 0, offset; 1830 1831 if (skb->ip_summed == CHECKSUM_COMPLETE) 1832 goto out_set_summed; 1833 1834 if (unlikely(skb_shinfo(skb)->gso_size)) { 1835 /* Let GSO fix up the checksum. */ 1836 goto out_set_summed; 1837 } 1838 1839 offset = skb_checksum_start_offset(skb); 1840 BUG_ON(offset >= skb_headlen(skb)); 1841 csum = skb_checksum(skb, offset, skb->len - offset, 0); 1842 1843 offset += skb->csum_offset; 1844 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); 1845 1846 if (skb_cloned(skb) && 1847 !skb_clone_writable(skb, offset + sizeof(__sum16))) { 1848 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 1849 if (ret) 1850 goto out; 1851 } 1852 1853 *(__sum16 *)(skb->data + offset) = csum_fold(csum); 1854 out_set_summed: 1855 skb->ip_summed = CHECKSUM_NONE; 1856 out: 1857 return ret; 1858 } 1859 EXPORT_SYMBOL(skb_checksum_help); 1860 1861 /** 1862 * skb_gso_segment - Perform segmentation on skb. 1863 * @skb: buffer to segment 1864 * @features: features for the output path (see dev->features) 1865 * 1866 * This function segments the given skb and returns a list of segments. 1867 * 1868 * It may return NULL if the skb requires no segmentation. This is 1869 * only possible when GSO is used for verifying header integrity. 1870 */ 1871 struct sk_buff *skb_gso_segment(struct sk_buff *skb, u32 features) 1872 { 1873 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); 1874 struct packet_type *ptype; 1875 __be16 type = skb->protocol; 1876 int vlan_depth = ETH_HLEN; 1877 int err; 1878 1879 while (type == htons(ETH_P_8021Q)) { 1880 struct vlan_hdr *vh; 1881 1882 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN))) 1883 return ERR_PTR(-EINVAL); 1884 1885 vh = (struct vlan_hdr *)(skb->data + vlan_depth); 1886 type = vh->h_vlan_encapsulated_proto; 1887 vlan_depth += VLAN_HLEN; 1888 } 1889 1890 skb_reset_mac_header(skb); 1891 skb->mac_len = skb->network_header - skb->mac_header; 1892 __skb_pull(skb, skb->mac_len); 1893 1894 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1895 struct net_device *dev = skb->dev; 1896 struct ethtool_drvinfo info = {}; 1897 1898 if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo) 1899 dev->ethtool_ops->get_drvinfo(dev, &info); 1900 1901 WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d ip_summed=%d\n", 1902 info.driver, dev ? dev->features : 0L, 1903 skb->sk ? skb->sk->sk_route_caps : 0L, 1904 skb->len, skb->data_len, skb->ip_summed); 1905 1906 if (skb_header_cloned(skb) && 1907 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) 1908 return ERR_PTR(err); 1909 } 1910 1911 rcu_read_lock(); 1912 list_for_each_entry_rcu(ptype, 1913 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 1914 if (ptype->type == type && !ptype->dev && ptype->gso_segment) { 1915 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1916 err = ptype->gso_send_check(skb); 1917 segs = ERR_PTR(err); 1918 if (err || skb_gso_ok(skb, features)) 1919 break; 1920 __skb_push(skb, (skb->data - 1921 skb_network_header(skb))); 1922 } 1923 segs = ptype->gso_segment(skb, features); 1924 break; 1925 } 1926 } 1927 rcu_read_unlock(); 1928 1929 __skb_push(skb, skb->data - skb_mac_header(skb)); 1930 1931 return segs; 1932 } 1933 EXPORT_SYMBOL(skb_gso_segment); 1934 1935 /* Take action when hardware reception checksum errors are detected. */ 1936 #ifdef CONFIG_BUG 1937 void netdev_rx_csum_fault(struct net_device *dev) 1938 { 1939 if (net_ratelimit()) { 1940 printk(KERN_ERR "%s: hw csum failure.\n", 1941 dev ? dev->name : "<unknown>"); 1942 dump_stack(); 1943 } 1944 } 1945 EXPORT_SYMBOL(netdev_rx_csum_fault); 1946 #endif 1947 1948 /* Actually, we should eliminate this check as soon as we know, that: 1949 * 1. IOMMU is present and allows to map all the memory. 1950 * 2. No high memory really exists on this machine. 1951 */ 1952 1953 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 1954 { 1955 #ifdef CONFIG_HIGHMEM 1956 int i; 1957 if (!(dev->features & NETIF_F_HIGHDMA)) { 1958 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 1959 if (PageHighMem(skb_shinfo(skb)->frags[i].page)) 1960 return 1; 1961 } 1962 1963 if (PCI_DMA_BUS_IS_PHYS) { 1964 struct device *pdev = dev->dev.parent; 1965 1966 if (!pdev) 1967 return 0; 1968 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 1969 dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page); 1970 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask) 1971 return 1; 1972 } 1973 } 1974 #endif 1975 return 0; 1976 } 1977 1978 struct dev_gso_cb { 1979 void (*destructor)(struct sk_buff *skb); 1980 }; 1981 1982 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) 1983 1984 static void dev_gso_skb_destructor(struct sk_buff *skb) 1985 { 1986 struct dev_gso_cb *cb; 1987 1988 do { 1989 struct sk_buff *nskb = skb->next; 1990 1991 skb->next = nskb->next; 1992 nskb->next = NULL; 1993 kfree_skb(nskb); 1994 } while (skb->next); 1995 1996 cb = DEV_GSO_CB(skb); 1997 if (cb->destructor) 1998 cb->destructor(skb); 1999 } 2000 2001 /** 2002 * dev_gso_segment - Perform emulated hardware segmentation on skb. 2003 * @skb: buffer to segment 2004 * @features: device features as applicable to this skb 2005 * 2006 * This function segments the given skb and stores the list of segments 2007 * in skb->next. 2008 */ 2009 static int dev_gso_segment(struct sk_buff *skb, int features) 2010 { 2011 struct sk_buff *segs; 2012 2013 segs = skb_gso_segment(skb, features); 2014 2015 /* Verifying header integrity only. */ 2016 if (!segs) 2017 return 0; 2018 2019 if (IS_ERR(segs)) 2020 return PTR_ERR(segs); 2021 2022 skb->next = segs; 2023 DEV_GSO_CB(skb)->destructor = skb->destructor; 2024 skb->destructor = dev_gso_skb_destructor; 2025 2026 return 0; 2027 } 2028 2029 /* 2030 * Try to orphan skb early, right before transmission by the device. 2031 * We cannot orphan skb if tx timestamp is requested or the sk-reference 2032 * is needed on driver level for other reasons, e.g. see net/can/raw.c 2033 */ 2034 static inline void skb_orphan_try(struct sk_buff *skb) 2035 { 2036 struct sock *sk = skb->sk; 2037 2038 if (sk && !skb_shinfo(skb)->tx_flags) { 2039 /* skb_tx_hash() wont be able to get sk. 2040 * We copy sk_hash into skb->rxhash 2041 */ 2042 if (!skb->rxhash) 2043 skb->rxhash = sk->sk_hash; 2044 skb_orphan(skb); 2045 } 2046 } 2047 2048 static bool can_checksum_protocol(unsigned long features, __be16 protocol) 2049 { 2050 return ((features & NETIF_F_GEN_CSUM) || 2051 ((features & NETIF_F_V4_CSUM) && 2052 protocol == htons(ETH_P_IP)) || 2053 ((features & NETIF_F_V6_CSUM) && 2054 protocol == htons(ETH_P_IPV6)) || 2055 ((features & NETIF_F_FCOE_CRC) && 2056 protocol == htons(ETH_P_FCOE))); 2057 } 2058 2059 static u32 harmonize_features(struct sk_buff *skb, __be16 protocol, u32 features) 2060 { 2061 if (!can_checksum_protocol(features, protocol)) { 2062 features &= ~NETIF_F_ALL_CSUM; 2063 features &= ~NETIF_F_SG; 2064 } else if (illegal_highdma(skb->dev, skb)) { 2065 features &= ~NETIF_F_SG; 2066 } 2067 2068 return features; 2069 } 2070 2071 u32 netif_skb_features(struct sk_buff *skb) 2072 { 2073 __be16 protocol = skb->protocol; 2074 u32 features = skb->dev->features; 2075 2076 if (protocol == htons(ETH_P_8021Q)) { 2077 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; 2078 protocol = veh->h_vlan_encapsulated_proto; 2079 } else if (!vlan_tx_tag_present(skb)) { 2080 return harmonize_features(skb, protocol, features); 2081 } 2082 2083 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_TX); 2084 2085 if (protocol != htons(ETH_P_8021Q)) { 2086 return harmonize_features(skb, protocol, features); 2087 } else { 2088 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | 2089 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX; 2090 return harmonize_features(skb, protocol, features); 2091 } 2092 } 2093 EXPORT_SYMBOL(netif_skb_features); 2094 2095 /* 2096 * Returns true if either: 2097 * 1. skb has frag_list and the device doesn't support FRAGLIST, or 2098 * 2. skb is fragmented and the device does not support SG, or if 2099 * at least one of fragments is in highmem and device does not 2100 * support DMA from it. 2101 */ 2102 static inline int skb_needs_linearize(struct sk_buff *skb, 2103 int features) 2104 { 2105 return skb_is_nonlinear(skb) && 2106 ((skb_has_frag_list(skb) && 2107 !(features & NETIF_F_FRAGLIST)) || 2108 (skb_shinfo(skb)->nr_frags && 2109 !(features & NETIF_F_SG))); 2110 } 2111 2112 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, 2113 struct netdev_queue *txq) 2114 { 2115 const struct net_device_ops *ops = dev->netdev_ops; 2116 int rc = NETDEV_TX_OK; 2117 unsigned int skb_len; 2118 2119 if (likely(!skb->next)) { 2120 u32 features; 2121 2122 /* 2123 * If device doesn't need skb->dst, release it right now while 2124 * its hot in this cpu cache 2125 */ 2126 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 2127 skb_dst_drop(skb); 2128 2129 if (!list_empty(&ptype_all)) 2130 dev_queue_xmit_nit(skb, dev); 2131 2132 skb_orphan_try(skb); 2133 2134 features = netif_skb_features(skb); 2135 2136 if (vlan_tx_tag_present(skb) && 2137 !(features & NETIF_F_HW_VLAN_TX)) { 2138 skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb)); 2139 if (unlikely(!skb)) 2140 goto out; 2141 2142 skb->vlan_tci = 0; 2143 } 2144 2145 if (netif_needs_gso(skb, features)) { 2146 if (unlikely(dev_gso_segment(skb, features))) 2147 goto out_kfree_skb; 2148 if (skb->next) 2149 goto gso; 2150 } else { 2151 if (skb_needs_linearize(skb, features) && 2152 __skb_linearize(skb)) 2153 goto out_kfree_skb; 2154 2155 /* If packet is not checksummed and device does not 2156 * support checksumming for this protocol, complete 2157 * checksumming here. 2158 */ 2159 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2160 skb_set_transport_header(skb, 2161 skb_checksum_start_offset(skb)); 2162 if (!(features & NETIF_F_ALL_CSUM) && 2163 skb_checksum_help(skb)) 2164 goto out_kfree_skb; 2165 } 2166 } 2167 2168 skb_len = skb->len; 2169 rc = ops->ndo_start_xmit(skb, dev); 2170 trace_net_dev_xmit(skb, rc, dev, skb_len); 2171 if (rc == NETDEV_TX_OK) 2172 txq_trans_update(txq); 2173 return rc; 2174 } 2175 2176 gso: 2177 do { 2178 struct sk_buff *nskb = skb->next; 2179 2180 skb->next = nskb->next; 2181 nskb->next = NULL; 2182 2183 /* 2184 * If device doesn't need nskb->dst, release it right now while 2185 * its hot in this cpu cache 2186 */ 2187 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 2188 skb_dst_drop(nskb); 2189 2190 skb_len = nskb->len; 2191 rc = ops->ndo_start_xmit(nskb, dev); 2192 trace_net_dev_xmit(nskb, rc, dev, skb_len); 2193 if (unlikely(rc != NETDEV_TX_OK)) { 2194 if (rc & ~NETDEV_TX_MASK) 2195 goto out_kfree_gso_skb; 2196 nskb->next = skb->next; 2197 skb->next = nskb; 2198 return rc; 2199 } 2200 txq_trans_update(txq); 2201 if (unlikely(netif_tx_queue_stopped(txq) && skb->next)) 2202 return NETDEV_TX_BUSY; 2203 } while (skb->next); 2204 2205 out_kfree_gso_skb: 2206 if (likely(skb->next == NULL)) 2207 skb->destructor = DEV_GSO_CB(skb)->destructor; 2208 out_kfree_skb: 2209 kfree_skb(skb); 2210 out: 2211 return rc; 2212 } 2213 2214 static u32 hashrnd __read_mostly; 2215 2216 /* 2217 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 2218 * to be used as a distribution range. 2219 */ 2220 u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb, 2221 unsigned int num_tx_queues) 2222 { 2223 u32 hash; 2224 u16 qoffset = 0; 2225 u16 qcount = num_tx_queues; 2226 2227 if (skb_rx_queue_recorded(skb)) { 2228 hash = skb_get_rx_queue(skb); 2229 while (unlikely(hash >= num_tx_queues)) 2230 hash -= num_tx_queues; 2231 return hash; 2232 } 2233 2234 if (dev->num_tc) { 2235 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 2236 qoffset = dev->tc_to_txq[tc].offset; 2237 qcount = dev->tc_to_txq[tc].count; 2238 } 2239 2240 if (skb->sk && skb->sk->sk_hash) 2241 hash = skb->sk->sk_hash; 2242 else 2243 hash = (__force u16) skb->protocol ^ skb->rxhash; 2244 hash = jhash_1word(hash, hashrnd); 2245 2246 return (u16) (((u64) hash * qcount) >> 32) + qoffset; 2247 } 2248 EXPORT_SYMBOL(__skb_tx_hash); 2249 2250 static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index) 2251 { 2252 if (unlikely(queue_index >= dev->real_num_tx_queues)) { 2253 if (net_ratelimit()) { 2254 pr_warning("%s selects TX queue %d, but " 2255 "real number of TX queues is %d\n", 2256 dev->name, queue_index, dev->real_num_tx_queues); 2257 } 2258 return 0; 2259 } 2260 return queue_index; 2261 } 2262 2263 static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb) 2264 { 2265 #ifdef CONFIG_XPS 2266 struct xps_dev_maps *dev_maps; 2267 struct xps_map *map; 2268 int queue_index = -1; 2269 2270 rcu_read_lock(); 2271 dev_maps = rcu_dereference(dev->xps_maps); 2272 if (dev_maps) { 2273 map = rcu_dereference( 2274 dev_maps->cpu_map[raw_smp_processor_id()]); 2275 if (map) { 2276 if (map->len == 1) 2277 queue_index = map->queues[0]; 2278 else { 2279 u32 hash; 2280 if (skb->sk && skb->sk->sk_hash) 2281 hash = skb->sk->sk_hash; 2282 else 2283 hash = (__force u16) skb->protocol ^ 2284 skb->rxhash; 2285 hash = jhash_1word(hash, hashrnd); 2286 queue_index = map->queues[ 2287 ((u64)hash * map->len) >> 32]; 2288 } 2289 if (unlikely(queue_index >= dev->real_num_tx_queues)) 2290 queue_index = -1; 2291 } 2292 } 2293 rcu_read_unlock(); 2294 2295 return queue_index; 2296 #else 2297 return -1; 2298 #endif 2299 } 2300 2301 static struct netdev_queue *dev_pick_tx(struct net_device *dev, 2302 struct sk_buff *skb) 2303 { 2304 int queue_index; 2305 const struct net_device_ops *ops = dev->netdev_ops; 2306 2307 if (dev->real_num_tx_queues == 1) 2308 queue_index = 0; 2309 else if (ops->ndo_select_queue) { 2310 queue_index = ops->ndo_select_queue(dev, skb); 2311 queue_index = dev_cap_txqueue(dev, queue_index); 2312 } else { 2313 struct sock *sk = skb->sk; 2314 queue_index = sk_tx_queue_get(sk); 2315 2316 if (queue_index < 0 || skb->ooo_okay || 2317 queue_index >= dev->real_num_tx_queues) { 2318 int old_index = queue_index; 2319 2320 queue_index = get_xps_queue(dev, skb); 2321 if (queue_index < 0) 2322 queue_index = skb_tx_hash(dev, skb); 2323 2324 if (queue_index != old_index && sk) { 2325 struct dst_entry *dst = 2326 rcu_dereference_check(sk->sk_dst_cache, 1); 2327 2328 if (dst && skb_dst(skb) == dst) 2329 sk_tx_queue_set(sk, queue_index); 2330 } 2331 } 2332 } 2333 2334 skb_set_queue_mapping(skb, queue_index); 2335 return netdev_get_tx_queue(dev, queue_index); 2336 } 2337 2338 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 2339 struct net_device *dev, 2340 struct netdev_queue *txq) 2341 { 2342 spinlock_t *root_lock = qdisc_lock(q); 2343 bool contended; 2344 int rc; 2345 2346 qdisc_skb_cb(skb)->pkt_len = skb->len; 2347 qdisc_calculate_pkt_len(skb, q); 2348 /* 2349 * Heuristic to force contended enqueues to serialize on a 2350 * separate lock before trying to get qdisc main lock. 2351 * This permits __QDISC_STATE_RUNNING owner to get the lock more often 2352 * and dequeue packets faster. 2353 */ 2354 contended = qdisc_is_running(q); 2355 if (unlikely(contended)) 2356 spin_lock(&q->busylock); 2357 2358 spin_lock(root_lock); 2359 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 2360 kfree_skb(skb); 2361 rc = NET_XMIT_DROP; 2362 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 2363 qdisc_run_begin(q)) { 2364 /* 2365 * This is a work-conserving queue; there are no old skbs 2366 * waiting to be sent out; and the qdisc is not running - 2367 * xmit the skb directly. 2368 */ 2369 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE)) 2370 skb_dst_force(skb); 2371 2372 qdisc_bstats_update(q, skb); 2373 2374 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) { 2375 if (unlikely(contended)) { 2376 spin_unlock(&q->busylock); 2377 contended = false; 2378 } 2379 __qdisc_run(q); 2380 } else 2381 qdisc_run_end(q); 2382 2383 rc = NET_XMIT_SUCCESS; 2384 } else { 2385 skb_dst_force(skb); 2386 rc = q->enqueue(skb, q) & NET_XMIT_MASK; 2387 if (qdisc_run_begin(q)) { 2388 if (unlikely(contended)) { 2389 spin_unlock(&q->busylock); 2390 contended = false; 2391 } 2392 __qdisc_run(q); 2393 } 2394 } 2395 spin_unlock(root_lock); 2396 if (unlikely(contended)) 2397 spin_unlock(&q->busylock); 2398 return rc; 2399 } 2400 2401 static DEFINE_PER_CPU(int, xmit_recursion); 2402 #define RECURSION_LIMIT 10 2403 2404 /** 2405 * dev_queue_xmit - transmit a buffer 2406 * @skb: buffer to transmit 2407 * 2408 * Queue a buffer for transmission to a network device. The caller must 2409 * have set the device and priority and built the buffer before calling 2410 * this function. The function can be called from an interrupt. 2411 * 2412 * A negative errno code is returned on a failure. A success does not 2413 * guarantee the frame will be transmitted as it may be dropped due 2414 * to congestion or traffic shaping. 2415 * 2416 * ----------------------------------------------------------------------------------- 2417 * I notice this method can also return errors from the queue disciplines, 2418 * including NET_XMIT_DROP, which is a positive value. So, errors can also 2419 * be positive. 2420 * 2421 * Regardless of the return value, the skb is consumed, so it is currently 2422 * difficult to retry a send to this method. (You can bump the ref count 2423 * before sending to hold a reference for retry if you are careful.) 2424 * 2425 * When calling this method, interrupts MUST be enabled. This is because 2426 * the BH enable code must have IRQs enabled so that it will not deadlock. 2427 * --BLG 2428 */ 2429 int dev_queue_xmit(struct sk_buff *skb) 2430 { 2431 struct net_device *dev = skb->dev; 2432 struct netdev_queue *txq; 2433 struct Qdisc *q; 2434 int rc = -ENOMEM; 2435 2436 /* Disable soft irqs for various locks below. Also 2437 * stops preemption for RCU. 2438 */ 2439 rcu_read_lock_bh(); 2440 2441 txq = dev_pick_tx(dev, skb); 2442 q = rcu_dereference_bh(txq->qdisc); 2443 2444 #ifdef CONFIG_NET_CLS_ACT 2445 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS); 2446 #endif 2447 trace_net_dev_queue(skb); 2448 if (q->enqueue) { 2449 rc = __dev_xmit_skb(skb, q, dev, txq); 2450 goto out; 2451 } 2452 2453 /* The device has no queue. Common case for software devices: 2454 loopback, all the sorts of tunnels... 2455 2456 Really, it is unlikely that netif_tx_lock protection is necessary 2457 here. (f.e. loopback and IP tunnels are clean ignoring statistics 2458 counters.) 2459 However, it is possible, that they rely on protection 2460 made by us here. 2461 2462 Check this and shot the lock. It is not prone from deadlocks. 2463 Either shot noqueue qdisc, it is even simpler 8) 2464 */ 2465 if (dev->flags & IFF_UP) { 2466 int cpu = smp_processor_id(); /* ok because BHs are off */ 2467 2468 if (txq->xmit_lock_owner != cpu) { 2469 2470 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT) 2471 goto recursion_alert; 2472 2473 HARD_TX_LOCK(dev, txq, cpu); 2474 2475 if (!netif_tx_queue_stopped(txq)) { 2476 __this_cpu_inc(xmit_recursion); 2477 rc = dev_hard_start_xmit(skb, dev, txq); 2478 __this_cpu_dec(xmit_recursion); 2479 if (dev_xmit_complete(rc)) { 2480 HARD_TX_UNLOCK(dev, txq); 2481 goto out; 2482 } 2483 } 2484 HARD_TX_UNLOCK(dev, txq); 2485 if (net_ratelimit()) 2486 printk(KERN_CRIT "Virtual device %s asks to " 2487 "queue packet!\n", dev->name); 2488 } else { 2489 /* Recursion is detected! It is possible, 2490 * unfortunately 2491 */ 2492 recursion_alert: 2493 if (net_ratelimit()) 2494 printk(KERN_CRIT "Dead loop on virtual device " 2495 "%s, fix it urgently!\n", dev->name); 2496 } 2497 } 2498 2499 rc = -ENETDOWN; 2500 rcu_read_unlock_bh(); 2501 2502 kfree_skb(skb); 2503 return rc; 2504 out: 2505 rcu_read_unlock_bh(); 2506 return rc; 2507 } 2508 EXPORT_SYMBOL(dev_queue_xmit); 2509 2510 2511 /*======================================================================= 2512 Receiver routines 2513 =======================================================================*/ 2514 2515 int netdev_max_backlog __read_mostly = 1000; 2516 int netdev_tstamp_prequeue __read_mostly = 1; 2517 int netdev_budget __read_mostly = 300; 2518 int weight_p __read_mostly = 64; /* old backlog weight */ 2519 2520 /* Called with irq disabled */ 2521 static inline void ____napi_schedule(struct softnet_data *sd, 2522 struct napi_struct *napi) 2523 { 2524 list_add_tail(&napi->poll_list, &sd->poll_list); 2525 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2526 } 2527 2528 /* 2529 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses 2530 * and src/dst port numbers. Returns a non-zero hash number on success 2531 * and 0 on failure. 2532 */ 2533 __u32 __skb_get_rxhash(struct sk_buff *skb) 2534 { 2535 int nhoff, hash = 0, poff; 2536 const struct ipv6hdr *ip6; 2537 const struct iphdr *ip; 2538 u8 ip_proto; 2539 u32 addr1, addr2, ihl; 2540 union { 2541 u32 v32; 2542 u16 v16[2]; 2543 } ports; 2544 2545 nhoff = skb_network_offset(skb); 2546 2547 switch (skb->protocol) { 2548 case __constant_htons(ETH_P_IP): 2549 if (!pskb_may_pull(skb, sizeof(*ip) + nhoff)) 2550 goto done; 2551 2552 ip = (const struct iphdr *) (skb->data + nhoff); 2553 if (ip_is_fragment(ip)) 2554 ip_proto = 0; 2555 else 2556 ip_proto = ip->protocol; 2557 addr1 = (__force u32) ip->saddr; 2558 addr2 = (__force u32) ip->daddr; 2559 ihl = ip->ihl; 2560 break; 2561 case __constant_htons(ETH_P_IPV6): 2562 if (!pskb_may_pull(skb, sizeof(*ip6) + nhoff)) 2563 goto done; 2564 2565 ip6 = (const struct ipv6hdr *) (skb->data + nhoff); 2566 ip_proto = ip6->nexthdr; 2567 addr1 = (__force u32) ip6->saddr.s6_addr32[3]; 2568 addr2 = (__force u32) ip6->daddr.s6_addr32[3]; 2569 ihl = (40 >> 2); 2570 break; 2571 default: 2572 goto done; 2573 } 2574 2575 ports.v32 = 0; 2576 poff = proto_ports_offset(ip_proto); 2577 if (poff >= 0) { 2578 nhoff += ihl * 4 + poff; 2579 if (pskb_may_pull(skb, nhoff + 4)) { 2580 ports.v32 = * (__force u32 *) (skb->data + nhoff); 2581 if (ports.v16[1] < ports.v16[0]) 2582 swap(ports.v16[0], ports.v16[1]); 2583 } 2584 } 2585 2586 /* get a consistent hash (same value on both flow directions) */ 2587 if (addr2 < addr1) 2588 swap(addr1, addr2); 2589 2590 hash = jhash_3words(addr1, addr2, ports.v32, hashrnd); 2591 if (!hash) 2592 hash = 1; 2593 2594 done: 2595 return hash; 2596 } 2597 EXPORT_SYMBOL(__skb_get_rxhash); 2598 2599 #ifdef CONFIG_RPS 2600 2601 /* One global table that all flow-based protocols share. */ 2602 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 2603 EXPORT_SYMBOL(rps_sock_flow_table); 2604 2605 static struct rps_dev_flow * 2606 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 2607 struct rps_dev_flow *rflow, u16 next_cpu) 2608 { 2609 u16 tcpu; 2610 2611 tcpu = rflow->cpu = next_cpu; 2612 if (tcpu != RPS_NO_CPU) { 2613 #ifdef CONFIG_RFS_ACCEL 2614 struct netdev_rx_queue *rxqueue; 2615 struct rps_dev_flow_table *flow_table; 2616 struct rps_dev_flow *old_rflow; 2617 u32 flow_id; 2618 u16 rxq_index; 2619 int rc; 2620 2621 /* Should we steer this flow to a different hardware queue? */ 2622 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 2623 !(dev->features & NETIF_F_NTUPLE)) 2624 goto out; 2625 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 2626 if (rxq_index == skb_get_rx_queue(skb)) 2627 goto out; 2628 2629 rxqueue = dev->_rx + rxq_index; 2630 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2631 if (!flow_table) 2632 goto out; 2633 flow_id = skb->rxhash & flow_table->mask; 2634 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 2635 rxq_index, flow_id); 2636 if (rc < 0) 2637 goto out; 2638 old_rflow = rflow; 2639 rflow = &flow_table->flows[flow_id]; 2640 rflow->cpu = next_cpu; 2641 rflow->filter = rc; 2642 if (old_rflow->filter == rflow->filter) 2643 old_rflow->filter = RPS_NO_FILTER; 2644 out: 2645 #endif 2646 rflow->last_qtail = 2647 per_cpu(softnet_data, tcpu).input_queue_head; 2648 } 2649 2650 return rflow; 2651 } 2652 2653 /* 2654 * get_rps_cpu is called from netif_receive_skb and returns the target 2655 * CPU from the RPS map of the receiving queue for a given skb. 2656 * rcu_read_lock must be held on entry. 2657 */ 2658 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 2659 struct rps_dev_flow **rflowp) 2660 { 2661 struct netdev_rx_queue *rxqueue; 2662 struct rps_map *map; 2663 struct rps_dev_flow_table *flow_table; 2664 struct rps_sock_flow_table *sock_flow_table; 2665 int cpu = -1; 2666 u16 tcpu; 2667 2668 if (skb_rx_queue_recorded(skb)) { 2669 u16 index = skb_get_rx_queue(skb); 2670 if (unlikely(index >= dev->real_num_rx_queues)) { 2671 WARN_ONCE(dev->real_num_rx_queues > 1, 2672 "%s received packet on queue %u, but number " 2673 "of RX queues is %u\n", 2674 dev->name, index, dev->real_num_rx_queues); 2675 goto done; 2676 } 2677 rxqueue = dev->_rx + index; 2678 } else 2679 rxqueue = dev->_rx; 2680 2681 map = rcu_dereference(rxqueue->rps_map); 2682 if (map) { 2683 if (map->len == 1 && 2684 !rcu_dereference_raw(rxqueue->rps_flow_table)) { 2685 tcpu = map->cpus[0]; 2686 if (cpu_online(tcpu)) 2687 cpu = tcpu; 2688 goto done; 2689 } 2690 } else if (!rcu_dereference_raw(rxqueue->rps_flow_table)) { 2691 goto done; 2692 } 2693 2694 skb_reset_network_header(skb); 2695 if (!skb_get_rxhash(skb)) 2696 goto done; 2697 2698 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2699 sock_flow_table = rcu_dereference(rps_sock_flow_table); 2700 if (flow_table && sock_flow_table) { 2701 u16 next_cpu; 2702 struct rps_dev_flow *rflow; 2703 2704 rflow = &flow_table->flows[skb->rxhash & flow_table->mask]; 2705 tcpu = rflow->cpu; 2706 2707 next_cpu = sock_flow_table->ents[skb->rxhash & 2708 sock_flow_table->mask]; 2709 2710 /* 2711 * If the desired CPU (where last recvmsg was done) is 2712 * different from current CPU (one in the rx-queue flow 2713 * table entry), switch if one of the following holds: 2714 * - Current CPU is unset (equal to RPS_NO_CPU). 2715 * - Current CPU is offline. 2716 * - The current CPU's queue tail has advanced beyond the 2717 * last packet that was enqueued using this table entry. 2718 * This guarantees that all previous packets for the flow 2719 * have been dequeued, thus preserving in order delivery. 2720 */ 2721 if (unlikely(tcpu != next_cpu) && 2722 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) || 2723 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 2724 rflow->last_qtail)) >= 0)) 2725 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 2726 2727 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) { 2728 *rflowp = rflow; 2729 cpu = tcpu; 2730 goto done; 2731 } 2732 } 2733 2734 if (map) { 2735 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32]; 2736 2737 if (cpu_online(tcpu)) { 2738 cpu = tcpu; 2739 goto done; 2740 } 2741 } 2742 2743 done: 2744 return cpu; 2745 } 2746 2747 #ifdef CONFIG_RFS_ACCEL 2748 2749 /** 2750 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 2751 * @dev: Device on which the filter was set 2752 * @rxq_index: RX queue index 2753 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 2754 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 2755 * 2756 * Drivers that implement ndo_rx_flow_steer() should periodically call 2757 * this function for each installed filter and remove the filters for 2758 * which it returns %true. 2759 */ 2760 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 2761 u32 flow_id, u16 filter_id) 2762 { 2763 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 2764 struct rps_dev_flow_table *flow_table; 2765 struct rps_dev_flow *rflow; 2766 bool expire = true; 2767 int cpu; 2768 2769 rcu_read_lock(); 2770 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2771 if (flow_table && flow_id <= flow_table->mask) { 2772 rflow = &flow_table->flows[flow_id]; 2773 cpu = ACCESS_ONCE(rflow->cpu); 2774 if (rflow->filter == filter_id && cpu != RPS_NO_CPU && 2775 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 2776 rflow->last_qtail) < 2777 (int)(10 * flow_table->mask))) 2778 expire = false; 2779 } 2780 rcu_read_unlock(); 2781 return expire; 2782 } 2783 EXPORT_SYMBOL(rps_may_expire_flow); 2784 2785 #endif /* CONFIG_RFS_ACCEL */ 2786 2787 /* Called from hardirq (IPI) context */ 2788 static void rps_trigger_softirq(void *data) 2789 { 2790 struct softnet_data *sd = data; 2791 2792 ____napi_schedule(sd, &sd->backlog); 2793 sd->received_rps++; 2794 } 2795 2796 #endif /* CONFIG_RPS */ 2797 2798 /* 2799 * Check if this softnet_data structure is another cpu one 2800 * If yes, queue it to our IPI list and return 1 2801 * If no, return 0 2802 */ 2803 static int rps_ipi_queued(struct softnet_data *sd) 2804 { 2805 #ifdef CONFIG_RPS 2806 struct softnet_data *mysd = &__get_cpu_var(softnet_data); 2807 2808 if (sd != mysd) { 2809 sd->rps_ipi_next = mysd->rps_ipi_list; 2810 mysd->rps_ipi_list = sd; 2811 2812 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2813 return 1; 2814 } 2815 #endif /* CONFIG_RPS */ 2816 return 0; 2817 } 2818 2819 /* 2820 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 2821 * queue (may be a remote CPU queue). 2822 */ 2823 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 2824 unsigned int *qtail) 2825 { 2826 struct softnet_data *sd; 2827 unsigned long flags; 2828 2829 sd = &per_cpu(softnet_data, cpu); 2830 2831 local_irq_save(flags); 2832 2833 rps_lock(sd); 2834 if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) { 2835 if (skb_queue_len(&sd->input_pkt_queue)) { 2836 enqueue: 2837 __skb_queue_tail(&sd->input_pkt_queue, skb); 2838 input_queue_tail_incr_save(sd, qtail); 2839 rps_unlock(sd); 2840 local_irq_restore(flags); 2841 return NET_RX_SUCCESS; 2842 } 2843 2844 /* Schedule NAPI for backlog device 2845 * We can use non atomic operation since we own the queue lock 2846 */ 2847 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { 2848 if (!rps_ipi_queued(sd)) 2849 ____napi_schedule(sd, &sd->backlog); 2850 } 2851 goto enqueue; 2852 } 2853 2854 sd->dropped++; 2855 rps_unlock(sd); 2856 2857 local_irq_restore(flags); 2858 2859 atomic_long_inc(&skb->dev->rx_dropped); 2860 kfree_skb(skb); 2861 return NET_RX_DROP; 2862 } 2863 2864 /** 2865 * netif_rx - post buffer to the network code 2866 * @skb: buffer to post 2867 * 2868 * This function receives a packet from a device driver and queues it for 2869 * the upper (protocol) levels to process. It always succeeds. The buffer 2870 * may be dropped during processing for congestion control or by the 2871 * protocol layers. 2872 * 2873 * return values: 2874 * NET_RX_SUCCESS (no congestion) 2875 * NET_RX_DROP (packet was dropped) 2876 * 2877 */ 2878 2879 int netif_rx(struct sk_buff *skb) 2880 { 2881 int ret; 2882 2883 /* if netpoll wants it, pretend we never saw it */ 2884 if (netpoll_rx(skb)) 2885 return NET_RX_DROP; 2886 2887 if (netdev_tstamp_prequeue) 2888 net_timestamp_check(skb); 2889 2890 trace_netif_rx(skb); 2891 #ifdef CONFIG_RPS 2892 { 2893 struct rps_dev_flow voidflow, *rflow = &voidflow; 2894 int cpu; 2895 2896 preempt_disable(); 2897 rcu_read_lock(); 2898 2899 cpu = get_rps_cpu(skb->dev, skb, &rflow); 2900 if (cpu < 0) 2901 cpu = smp_processor_id(); 2902 2903 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 2904 2905 rcu_read_unlock(); 2906 preempt_enable(); 2907 } 2908 #else 2909 { 2910 unsigned int qtail; 2911 ret = enqueue_to_backlog(skb, get_cpu(), &qtail); 2912 put_cpu(); 2913 } 2914 #endif 2915 return ret; 2916 } 2917 EXPORT_SYMBOL(netif_rx); 2918 2919 int netif_rx_ni(struct sk_buff *skb) 2920 { 2921 int err; 2922 2923 preempt_disable(); 2924 err = netif_rx(skb); 2925 if (local_softirq_pending()) 2926 do_softirq(); 2927 preempt_enable(); 2928 2929 return err; 2930 } 2931 EXPORT_SYMBOL(netif_rx_ni); 2932 2933 static void net_tx_action(struct softirq_action *h) 2934 { 2935 struct softnet_data *sd = &__get_cpu_var(softnet_data); 2936 2937 if (sd->completion_queue) { 2938 struct sk_buff *clist; 2939 2940 local_irq_disable(); 2941 clist = sd->completion_queue; 2942 sd->completion_queue = NULL; 2943 local_irq_enable(); 2944 2945 while (clist) { 2946 struct sk_buff *skb = clist; 2947 clist = clist->next; 2948 2949 WARN_ON(atomic_read(&skb->users)); 2950 trace_kfree_skb(skb, net_tx_action); 2951 __kfree_skb(skb); 2952 } 2953 } 2954 2955 if (sd->output_queue) { 2956 struct Qdisc *head; 2957 2958 local_irq_disable(); 2959 head = sd->output_queue; 2960 sd->output_queue = NULL; 2961 sd->output_queue_tailp = &sd->output_queue; 2962 local_irq_enable(); 2963 2964 while (head) { 2965 struct Qdisc *q = head; 2966 spinlock_t *root_lock; 2967 2968 head = head->next_sched; 2969 2970 root_lock = qdisc_lock(q); 2971 if (spin_trylock(root_lock)) { 2972 smp_mb__before_clear_bit(); 2973 clear_bit(__QDISC_STATE_SCHED, 2974 &q->state); 2975 qdisc_run(q); 2976 spin_unlock(root_lock); 2977 } else { 2978 if (!test_bit(__QDISC_STATE_DEACTIVATED, 2979 &q->state)) { 2980 __netif_reschedule(q); 2981 } else { 2982 smp_mb__before_clear_bit(); 2983 clear_bit(__QDISC_STATE_SCHED, 2984 &q->state); 2985 } 2986 } 2987 } 2988 } 2989 } 2990 2991 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \ 2992 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)) 2993 /* This hook is defined here for ATM LANE */ 2994 int (*br_fdb_test_addr_hook)(struct net_device *dev, 2995 unsigned char *addr) __read_mostly; 2996 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 2997 #endif 2998 2999 #ifdef CONFIG_NET_CLS_ACT 3000 /* TODO: Maybe we should just force sch_ingress to be compiled in 3001 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions 3002 * a compare and 2 stores extra right now if we dont have it on 3003 * but have CONFIG_NET_CLS_ACT 3004 * NOTE: This doesn't stop any functionality; if you dont have 3005 * the ingress scheduler, you just can't add policies on ingress. 3006 * 3007 */ 3008 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq) 3009 { 3010 struct net_device *dev = skb->dev; 3011 u32 ttl = G_TC_RTTL(skb->tc_verd); 3012 int result = TC_ACT_OK; 3013 struct Qdisc *q; 3014 3015 if (unlikely(MAX_RED_LOOP < ttl++)) { 3016 if (net_ratelimit()) 3017 pr_warning( "Redir loop detected Dropping packet (%d->%d)\n", 3018 skb->skb_iif, dev->ifindex); 3019 return TC_ACT_SHOT; 3020 } 3021 3022 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl); 3023 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS); 3024 3025 q = rxq->qdisc; 3026 if (q != &noop_qdisc) { 3027 spin_lock(qdisc_lock(q)); 3028 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) 3029 result = qdisc_enqueue_root(skb, q); 3030 spin_unlock(qdisc_lock(q)); 3031 } 3032 3033 return result; 3034 } 3035 3036 static inline struct sk_buff *handle_ing(struct sk_buff *skb, 3037 struct packet_type **pt_prev, 3038 int *ret, struct net_device *orig_dev) 3039 { 3040 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue); 3041 3042 if (!rxq || rxq->qdisc == &noop_qdisc) 3043 goto out; 3044 3045 if (*pt_prev) { 3046 *ret = deliver_skb(skb, *pt_prev, orig_dev); 3047 *pt_prev = NULL; 3048 } 3049 3050 switch (ing_filter(skb, rxq)) { 3051 case TC_ACT_SHOT: 3052 case TC_ACT_STOLEN: 3053 kfree_skb(skb); 3054 return NULL; 3055 } 3056 3057 out: 3058 skb->tc_verd = 0; 3059 return skb; 3060 } 3061 #endif 3062 3063 /** 3064 * netdev_rx_handler_register - register receive handler 3065 * @dev: device to register a handler for 3066 * @rx_handler: receive handler to register 3067 * @rx_handler_data: data pointer that is used by rx handler 3068 * 3069 * Register a receive hander for a device. This handler will then be 3070 * called from __netif_receive_skb. A negative errno code is returned 3071 * on a failure. 3072 * 3073 * The caller must hold the rtnl_mutex. 3074 * 3075 * For a general description of rx_handler, see enum rx_handler_result. 3076 */ 3077 int netdev_rx_handler_register(struct net_device *dev, 3078 rx_handler_func_t *rx_handler, 3079 void *rx_handler_data) 3080 { 3081 ASSERT_RTNL(); 3082 3083 if (dev->rx_handler) 3084 return -EBUSY; 3085 3086 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 3087 rcu_assign_pointer(dev->rx_handler, rx_handler); 3088 3089 return 0; 3090 } 3091 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 3092 3093 /** 3094 * netdev_rx_handler_unregister - unregister receive handler 3095 * @dev: device to unregister a handler from 3096 * 3097 * Unregister a receive hander from a device. 3098 * 3099 * The caller must hold the rtnl_mutex. 3100 */ 3101 void netdev_rx_handler_unregister(struct net_device *dev) 3102 { 3103 3104 ASSERT_RTNL(); 3105 rcu_assign_pointer(dev->rx_handler, NULL); 3106 rcu_assign_pointer(dev->rx_handler_data, NULL); 3107 } 3108 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 3109 3110 static int __netif_receive_skb(struct sk_buff *skb) 3111 { 3112 struct packet_type *ptype, *pt_prev; 3113 rx_handler_func_t *rx_handler; 3114 struct net_device *orig_dev; 3115 struct net_device *null_or_dev; 3116 bool deliver_exact = false; 3117 int ret = NET_RX_DROP; 3118 __be16 type; 3119 3120 if (!netdev_tstamp_prequeue) 3121 net_timestamp_check(skb); 3122 3123 trace_netif_receive_skb(skb); 3124 3125 /* if we've gotten here through NAPI, check netpoll */ 3126 if (netpoll_receive_skb(skb)) 3127 return NET_RX_DROP; 3128 3129 if (!skb->skb_iif) 3130 skb->skb_iif = skb->dev->ifindex; 3131 orig_dev = skb->dev; 3132 3133 skb_reset_network_header(skb); 3134 skb_reset_transport_header(skb); 3135 skb_reset_mac_len(skb); 3136 3137 pt_prev = NULL; 3138 3139 rcu_read_lock(); 3140 3141 another_round: 3142 3143 __this_cpu_inc(softnet_data.processed); 3144 3145 if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) { 3146 skb = vlan_untag(skb); 3147 if (unlikely(!skb)) 3148 goto out; 3149 } 3150 3151 #ifdef CONFIG_NET_CLS_ACT 3152 if (skb->tc_verd & TC_NCLS) { 3153 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); 3154 goto ncls; 3155 } 3156 #endif 3157 3158 list_for_each_entry_rcu(ptype, &ptype_all, list) { 3159 if (!ptype->dev || ptype->dev == skb->dev) { 3160 if (pt_prev) 3161 ret = deliver_skb(skb, pt_prev, orig_dev); 3162 pt_prev = ptype; 3163 } 3164 } 3165 3166 #ifdef CONFIG_NET_CLS_ACT 3167 skb = handle_ing(skb, &pt_prev, &ret, orig_dev); 3168 if (!skb) 3169 goto out; 3170 ncls: 3171 #endif 3172 3173 rx_handler = rcu_dereference(skb->dev->rx_handler); 3174 if (rx_handler) { 3175 if (pt_prev) { 3176 ret = deliver_skb(skb, pt_prev, orig_dev); 3177 pt_prev = NULL; 3178 } 3179 switch (rx_handler(&skb)) { 3180 case RX_HANDLER_CONSUMED: 3181 goto out; 3182 case RX_HANDLER_ANOTHER: 3183 goto another_round; 3184 case RX_HANDLER_EXACT: 3185 deliver_exact = true; 3186 case RX_HANDLER_PASS: 3187 break; 3188 default: 3189 BUG(); 3190 } 3191 } 3192 3193 if (vlan_tx_tag_present(skb)) { 3194 if (pt_prev) { 3195 ret = deliver_skb(skb, pt_prev, orig_dev); 3196 pt_prev = NULL; 3197 } 3198 if (vlan_do_receive(&skb)) { 3199 ret = __netif_receive_skb(skb); 3200 goto out; 3201 } else if (unlikely(!skb)) 3202 goto out; 3203 } 3204 3205 /* deliver only exact match when indicated */ 3206 null_or_dev = deliver_exact ? skb->dev : NULL; 3207 3208 type = skb->protocol; 3209 list_for_each_entry_rcu(ptype, 3210 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 3211 if (ptype->type == type && 3212 (ptype->dev == null_or_dev || ptype->dev == skb->dev || 3213 ptype->dev == orig_dev)) { 3214 if (pt_prev) 3215 ret = deliver_skb(skb, pt_prev, orig_dev); 3216 pt_prev = ptype; 3217 } 3218 } 3219 3220 if (pt_prev) { 3221 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 3222 } else { 3223 atomic_long_inc(&skb->dev->rx_dropped); 3224 kfree_skb(skb); 3225 /* Jamal, now you will not able to escape explaining 3226 * me how you were going to use this. :-) 3227 */ 3228 ret = NET_RX_DROP; 3229 } 3230 3231 out: 3232 rcu_read_unlock(); 3233 return ret; 3234 } 3235 3236 /** 3237 * netif_receive_skb - process receive buffer from network 3238 * @skb: buffer to process 3239 * 3240 * netif_receive_skb() is the main receive data processing function. 3241 * It always succeeds. The buffer may be dropped during processing 3242 * for congestion control or by the protocol layers. 3243 * 3244 * This function may only be called from softirq context and interrupts 3245 * should be enabled. 3246 * 3247 * Return values (usually ignored): 3248 * NET_RX_SUCCESS: no congestion 3249 * NET_RX_DROP: packet was dropped 3250 */ 3251 int netif_receive_skb(struct sk_buff *skb) 3252 { 3253 if (netdev_tstamp_prequeue) 3254 net_timestamp_check(skb); 3255 3256 if (skb_defer_rx_timestamp(skb)) 3257 return NET_RX_SUCCESS; 3258 3259 #ifdef CONFIG_RPS 3260 { 3261 struct rps_dev_flow voidflow, *rflow = &voidflow; 3262 int cpu, ret; 3263 3264 rcu_read_lock(); 3265 3266 cpu = get_rps_cpu(skb->dev, skb, &rflow); 3267 3268 if (cpu >= 0) { 3269 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 3270 rcu_read_unlock(); 3271 } else { 3272 rcu_read_unlock(); 3273 ret = __netif_receive_skb(skb); 3274 } 3275 3276 return ret; 3277 } 3278 #else 3279 return __netif_receive_skb(skb); 3280 #endif 3281 } 3282 EXPORT_SYMBOL(netif_receive_skb); 3283 3284 /* Network device is going away, flush any packets still pending 3285 * Called with irqs disabled. 3286 */ 3287 static void flush_backlog(void *arg) 3288 { 3289 struct net_device *dev = arg; 3290 struct softnet_data *sd = &__get_cpu_var(softnet_data); 3291 struct sk_buff *skb, *tmp; 3292 3293 rps_lock(sd); 3294 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 3295 if (skb->dev == dev) { 3296 __skb_unlink(skb, &sd->input_pkt_queue); 3297 kfree_skb(skb); 3298 input_queue_head_incr(sd); 3299 } 3300 } 3301 rps_unlock(sd); 3302 3303 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 3304 if (skb->dev == dev) { 3305 __skb_unlink(skb, &sd->process_queue); 3306 kfree_skb(skb); 3307 input_queue_head_incr(sd); 3308 } 3309 } 3310 } 3311 3312 static int napi_gro_complete(struct sk_buff *skb) 3313 { 3314 struct packet_type *ptype; 3315 __be16 type = skb->protocol; 3316 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 3317 int err = -ENOENT; 3318 3319 if (NAPI_GRO_CB(skb)->count == 1) { 3320 skb_shinfo(skb)->gso_size = 0; 3321 goto out; 3322 } 3323 3324 rcu_read_lock(); 3325 list_for_each_entry_rcu(ptype, head, list) { 3326 if (ptype->type != type || ptype->dev || !ptype->gro_complete) 3327 continue; 3328 3329 err = ptype->gro_complete(skb); 3330 break; 3331 } 3332 rcu_read_unlock(); 3333 3334 if (err) { 3335 WARN_ON(&ptype->list == head); 3336 kfree_skb(skb); 3337 return NET_RX_SUCCESS; 3338 } 3339 3340 out: 3341 return netif_receive_skb(skb); 3342 } 3343 3344 inline void napi_gro_flush(struct napi_struct *napi) 3345 { 3346 struct sk_buff *skb, *next; 3347 3348 for (skb = napi->gro_list; skb; skb = next) { 3349 next = skb->next; 3350 skb->next = NULL; 3351 napi_gro_complete(skb); 3352 } 3353 3354 napi->gro_count = 0; 3355 napi->gro_list = NULL; 3356 } 3357 EXPORT_SYMBOL(napi_gro_flush); 3358 3359 enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3360 { 3361 struct sk_buff **pp = NULL; 3362 struct packet_type *ptype; 3363 __be16 type = skb->protocol; 3364 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 3365 int same_flow; 3366 int mac_len; 3367 enum gro_result ret; 3368 3369 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb)) 3370 goto normal; 3371 3372 if (skb_is_gso(skb) || skb_has_frag_list(skb)) 3373 goto normal; 3374 3375 rcu_read_lock(); 3376 list_for_each_entry_rcu(ptype, head, list) { 3377 if (ptype->type != type || ptype->dev || !ptype->gro_receive) 3378 continue; 3379 3380 skb_set_network_header(skb, skb_gro_offset(skb)); 3381 mac_len = skb->network_header - skb->mac_header; 3382 skb->mac_len = mac_len; 3383 NAPI_GRO_CB(skb)->same_flow = 0; 3384 NAPI_GRO_CB(skb)->flush = 0; 3385 NAPI_GRO_CB(skb)->free = 0; 3386 3387 pp = ptype->gro_receive(&napi->gro_list, skb); 3388 break; 3389 } 3390 rcu_read_unlock(); 3391 3392 if (&ptype->list == head) 3393 goto normal; 3394 3395 same_flow = NAPI_GRO_CB(skb)->same_flow; 3396 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; 3397 3398 if (pp) { 3399 struct sk_buff *nskb = *pp; 3400 3401 *pp = nskb->next; 3402 nskb->next = NULL; 3403 napi_gro_complete(nskb); 3404 napi->gro_count--; 3405 } 3406 3407 if (same_flow) 3408 goto ok; 3409 3410 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS) 3411 goto normal; 3412 3413 napi->gro_count++; 3414 NAPI_GRO_CB(skb)->count = 1; 3415 skb_shinfo(skb)->gso_size = skb_gro_len(skb); 3416 skb->next = napi->gro_list; 3417 napi->gro_list = skb; 3418 ret = GRO_HELD; 3419 3420 pull: 3421 if (skb_headlen(skb) < skb_gro_offset(skb)) { 3422 int grow = skb_gro_offset(skb) - skb_headlen(skb); 3423 3424 BUG_ON(skb->end - skb->tail < grow); 3425 3426 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); 3427 3428 skb->tail += grow; 3429 skb->data_len -= grow; 3430 3431 skb_shinfo(skb)->frags[0].page_offset += grow; 3432 skb_shinfo(skb)->frags[0].size -= grow; 3433 3434 if (unlikely(!skb_shinfo(skb)->frags[0].size)) { 3435 put_page(skb_shinfo(skb)->frags[0].page); 3436 memmove(skb_shinfo(skb)->frags, 3437 skb_shinfo(skb)->frags + 1, 3438 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t)); 3439 } 3440 } 3441 3442 ok: 3443 return ret; 3444 3445 normal: 3446 ret = GRO_NORMAL; 3447 goto pull; 3448 } 3449 EXPORT_SYMBOL(dev_gro_receive); 3450 3451 static inline gro_result_t 3452 __napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3453 { 3454 struct sk_buff *p; 3455 3456 for (p = napi->gro_list; p; p = p->next) { 3457 unsigned long diffs; 3458 3459 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; 3460 diffs |= p->vlan_tci ^ skb->vlan_tci; 3461 diffs |= compare_ether_header(skb_mac_header(p), 3462 skb_gro_mac_header(skb)); 3463 NAPI_GRO_CB(p)->same_flow = !diffs; 3464 NAPI_GRO_CB(p)->flush = 0; 3465 } 3466 3467 return dev_gro_receive(napi, skb); 3468 } 3469 3470 gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) 3471 { 3472 switch (ret) { 3473 case GRO_NORMAL: 3474 if (netif_receive_skb(skb)) 3475 ret = GRO_DROP; 3476 break; 3477 3478 case GRO_DROP: 3479 case GRO_MERGED_FREE: 3480 kfree_skb(skb); 3481 break; 3482 3483 case GRO_HELD: 3484 case GRO_MERGED: 3485 break; 3486 } 3487 3488 return ret; 3489 } 3490 EXPORT_SYMBOL(napi_skb_finish); 3491 3492 void skb_gro_reset_offset(struct sk_buff *skb) 3493 { 3494 NAPI_GRO_CB(skb)->data_offset = 0; 3495 NAPI_GRO_CB(skb)->frag0 = NULL; 3496 NAPI_GRO_CB(skb)->frag0_len = 0; 3497 3498 if (skb->mac_header == skb->tail && 3499 !PageHighMem(skb_shinfo(skb)->frags[0].page)) { 3500 NAPI_GRO_CB(skb)->frag0 = 3501 page_address(skb_shinfo(skb)->frags[0].page) + 3502 skb_shinfo(skb)->frags[0].page_offset; 3503 NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size; 3504 } 3505 } 3506 EXPORT_SYMBOL(skb_gro_reset_offset); 3507 3508 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3509 { 3510 skb_gro_reset_offset(skb); 3511 3512 return napi_skb_finish(__napi_gro_receive(napi, skb), skb); 3513 } 3514 EXPORT_SYMBOL(napi_gro_receive); 3515 3516 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) 3517 { 3518 __skb_pull(skb, skb_headlen(skb)); 3519 skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb)); 3520 skb->vlan_tci = 0; 3521 skb->dev = napi->dev; 3522 skb->skb_iif = 0; 3523 3524 napi->skb = skb; 3525 } 3526 3527 struct sk_buff *napi_get_frags(struct napi_struct *napi) 3528 { 3529 struct sk_buff *skb = napi->skb; 3530 3531 if (!skb) { 3532 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD); 3533 if (skb) 3534 napi->skb = skb; 3535 } 3536 return skb; 3537 } 3538 EXPORT_SYMBOL(napi_get_frags); 3539 3540 gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, 3541 gro_result_t ret) 3542 { 3543 switch (ret) { 3544 case GRO_NORMAL: 3545 case GRO_HELD: 3546 skb->protocol = eth_type_trans(skb, skb->dev); 3547 3548 if (ret == GRO_HELD) 3549 skb_gro_pull(skb, -ETH_HLEN); 3550 else if (netif_receive_skb(skb)) 3551 ret = GRO_DROP; 3552 break; 3553 3554 case GRO_DROP: 3555 case GRO_MERGED_FREE: 3556 napi_reuse_skb(napi, skb); 3557 break; 3558 3559 case GRO_MERGED: 3560 break; 3561 } 3562 3563 return ret; 3564 } 3565 EXPORT_SYMBOL(napi_frags_finish); 3566 3567 struct sk_buff *napi_frags_skb(struct napi_struct *napi) 3568 { 3569 struct sk_buff *skb = napi->skb; 3570 struct ethhdr *eth; 3571 unsigned int hlen; 3572 unsigned int off; 3573 3574 napi->skb = NULL; 3575 3576 skb_reset_mac_header(skb); 3577 skb_gro_reset_offset(skb); 3578 3579 off = skb_gro_offset(skb); 3580 hlen = off + sizeof(*eth); 3581 eth = skb_gro_header_fast(skb, off); 3582 if (skb_gro_header_hard(skb, hlen)) { 3583 eth = skb_gro_header_slow(skb, hlen, off); 3584 if (unlikely(!eth)) { 3585 napi_reuse_skb(napi, skb); 3586 skb = NULL; 3587 goto out; 3588 } 3589 } 3590 3591 skb_gro_pull(skb, sizeof(*eth)); 3592 3593 /* 3594 * This works because the only protocols we care about don't require 3595 * special handling. We'll fix it up properly at the end. 3596 */ 3597 skb->protocol = eth->h_proto; 3598 3599 out: 3600 return skb; 3601 } 3602 EXPORT_SYMBOL(napi_frags_skb); 3603 3604 gro_result_t napi_gro_frags(struct napi_struct *napi) 3605 { 3606 struct sk_buff *skb = napi_frags_skb(napi); 3607 3608 if (!skb) 3609 return GRO_DROP; 3610 3611 return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb)); 3612 } 3613 EXPORT_SYMBOL(napi_gro_frags); 3614 3615 /* 3616 * net_rps_action sends any pending IPI's for rps. 3617 * Note: called with local irq disabled, but exits with local irq enabled. 3618 */ 3619 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 3620 { 3621 #ifdef CONFIG_RPS 3622 struct softnet_data *remsd = sd->rps_ipi_list; 3623 3624 if (remsd) { 3625 sd->rps_ipi_list = NULL; 3626 3627 local_irq_enable(); 3628 3629 /* Send pending IPI's to kick RPS processing on remote cpus. */ 3630 while (remsd) { 3631 struct softnet_data *next = remsd->rps_ipi_next; 3632 3633 if (cpu_online(remsd->cpu)) 3634 __smp_call_function_single(remsd->cpu, 3635 &remsd->csd, 0); 3636 remsd = next; 3637 } 3638 } else 3639 #endif 3640 local_irq_enable(); 3641 } 3642 3643 static int process_backlog(struct napi_struct *napi, int quota) 3644 { 3645 int work = 0; 3646 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 3647 3648 #ifdef CONFIG_RPS 3649 /* Check if we have pending ipi, its better to send them now, 3650 * not waiting net_rx_action() end. 3651 */ 3652 if (sd->rps_ipi_list) { 3653 local_irq_disable(); 3654 net_rps_action_and_irq_enable(sd); 3655 } 3656 #endif 3657 napi->weight = weight_p; 3658 local_irq_disable(); 3659 while (work < quota) { 3660 struct sk_buff *skb; 3661 unsigned int qlen; 3662 3663 while ((skb = __skb_dequeue(&sd->process_queue))) { 3664 local_irq_enable(); 3665 __netif_receive_skb(skb); 3666 local_irq_disable(); 3667 input_queue_head_incr(sd); 3668 if (++work >= quota) { 3669 local_irq_enable(); 3670 return work; 3671 } 3672 } 3673 3674 rps_lock(sd); 3675 qlen = skb_queue_len(&sd->input_pkt_queue); 3676 if (qlen) 3677 skb_queue_splice_tail_init(&sd->input_pkt_queue, 3678 &sd->process_queue); 3679 3680 if (qlen < quota - work) { 3681 /* 3682 * Inline a custom version of __napi_complete(). 3683 * only current cpu owns and manipulates this napi, 3684 * and NAPI_STATE_SCHED is the only possible flag set on backlog. 3685 * we can use a plain write instead of clear_bit(), 3686 * and we dont need an smp_mb() memory barrier. 3687 */ 3688 list_del(&napi->poll_list); 3689 napi->state = 0; 3690 3691 quota = work + qlen; 3692 } 3693 rps_unlock(sd); 3694 } 3695 local_irq_enable(); 3696 3697 return work; 3698 } 3699 3700 /** 3701 * __napi_schedule - schedule for receive 3702 * @n: entry to schedule 3703 * 3704 * The entry's receive function will be scheduled to run 3705 */ 3706 void __napi_schedule(struct napi_struct *n) 3707 { 3708 unsigned long flags; 3709 3710 local_irq_save(flags); 3711 ____napi_schedule(&__get_cpu_var(softnet_data), n); 3712 local_irq_restore(flags); 3713 } 3714 EXPORT_SYMBOL(__napi_schedule); 3715 3716 void __napi_complete(struct napi_struct *n) 3717 { 3718 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); 3719 BUG_ON(n->gro_list); 3720 3721 list_del(&n->poll_list); 3722 smp_mb__before_clear_bit(); 3723 clear_bit(NAPI_STATE_SCHED, &n->state); 3724 } 3725 EXPORT_SYMBOL(__napi_complete); 3726 3727 void napi_complete(struct napi_struct *n) 3728 { 3729 unsigned long flags; 3730 3731 /* 3732 * don't let napi dequeue from the cpu poll list 3733 * just in case its running on a different cpu 3734 */ 3735 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state))) 3736 return; 3737 3738 napi_gro_flush(n); 3739 local_irq_save(flags); 3740 __napi_complete(n); 3741 local_irq_restore(flags); 3742 } 3743 EXPORT_SYMBOL(napi_complete); 3744 3745 void netif_napi_add(struct net_device *dev, struct napi_struct *napi, 3746 int (*poll)(struct napi_struct *, int), int weight) 3747 { 3748 INIT_LIST_HEAD(&napi->poll_list); 3749 napi->gro_count = 0; 3750 napi->gro_list = NULL; 3751 napi->skb = NULL; 3752 napi->poll = poll; 3753 napi->weight = weight; 3754 list_add(&napi->dev_list, &dev->napi_list); 3755 napi->dev = dev; 3756 #ifdef CONFIG_NETPOLL 3757 spin_lock_init(&napi->poll_lock); 3758 napi->poll_owner = -1; 3759 #endif 3760 set_bit(NAPI_STATE_SCHED, &napi->state); 3761 } 3762 EXPORT_SYMBOL(netif_napi_add); 3763 3764 void netif_napi_del(struct napi_struct *napi) 3765 { 3766 struct sk_buff *skb, *next; 3767 3768 list_del_init(&napi->dev_list); 3769 napi_free_frags(napi); 3770 3771 for (skb = napi->gro_list; skb; skb = next) { 3772 next = skb->next; 3773 skb->next = NULL; 3774 kfree_skb(skb); 3775 } 3776 3777 napi->gro_list = NULL; 3778 napi->gro_count = 0; 3779 } 3780 EXPORT_SYMBOL(netif_napi_del); 3781 3782 static void net_rx_action(struct softirq_action *h) 3783 { 3784 struct softnet_data *sd = &__get_cpu_var(softnet_data); 3785 unsigned long time_limit = jiffies + 2; 3786 int budget = netdev_budget; 3787 void *have; 3788 3789 local_irq_disable(); 3790 3791 while (!list_empty(&sd->poll_list)) { 3792 struct napi_struct *n; 3793 int work, weight; 3794 3795 /* If softirq window is exhuasted then punt. 3796 * Allow this to run for 2 jiffies since which will allow 3797 * an average latency of 1.5/HZ. 3798 */ 3799 if (unlikely(budget <= 0 || time_after(jiffies, time_limit))) 3800 goto softnet_break; 3801 3802 local_irq_enable(); 3803 3804 /* Even though interrupts have been re-enabled, this 3805 * access is safe because interrupts can only add new 3806 * entries to the tail of this list, and only ->poll() 3807 * calls can remove this head entry from the list. 3808 */ 3809 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list); 3810 3811 have = netpoll_poll_lock(n); 3812 3813 weight = n->weight; 3814 3815 /* This NAPI_STATE_SCHED test is for avoiding a race 3816 * with netpoll's poll_napi(). Only the entity which 3817 * obtains the lock and sees NAPI_STATE_SCHED set will 3818 * actually make the ->poll() call. Therefore we avoid 3819 * accidentally calling ->poll() when NAPI is not scheduled. 3820 */ 3821 work = 0; 3822 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 3823 work = n->poll(n, weight); 3824 trace_napi_poll(n); 3825 } 3826 3827 WARN_ON_ONCE(work > weight); 3828 3829 budget -= work; 3830 3831 local_irq_disable(); 3832 3833 /* Drivers must not modify the NAPI state if they 3834 * consume the entire weight. In such cases this code 3835 * still "owns" the NAPI instance and therefore can 3836 * move the instance around on the list at-will. 3837 */ 3838 if (unlikely(work == weight)) { 3839 if (unlikely(napi_disable_pending(n))) { 3840 local_irq_enable(); 3841 napi_complete(n); 3842 local_irq_disable(); 3843 } else 3844 list_move_tail(&n->poll_list, &sd->poll_list); 3845 } 3846 3847 netpoll_poll_unlock(have); 3848 } 3849 out: 3850 net_rps_action_and_irq_enable(sd); 3851 3852 #ifdef CONFIG_NET_DMA 3853 /* 3854 * There may not be any more sk_buffs coming right now, so push 3855 * any pending DMA copies to hardware 3856 */ 3857 dma_issue_pending_all(); 3858 #endif 3859 3860 return; 3861 3862 softnet_break: 3863 sd->time_squeeze++; 3864 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 3865 goto out; 3866 } 3867 3868 static gifconf_func_t *gifconf_list[NPROTO]; 3869 3870 /** 3871 * register_gifconf - register a SIOCGIF handler 3872 * @family: Address family 3873 * @gifconf: Function handler 3874 * 3875 * Register protocol dependent address dumping routines. The handler 3876 * that is passed must not be freed or reused until it has been replaced 3877 * by another handler. 3878 */ 3879 int register_gifconf(unsigned int family, gifconf_func_t *gifconf) 3880 { 3881 if (family >= NPROTO) 3882 return -EINVAL; 3883 gifconf_list[family] = gifconf; 3884 return 0; 3885 } 3886 EXPORT_SYMBOL(register_gifconf); 3887 3888 3889 /* 3890 * Map an interface index to its name (SIOCGIFNAME) 3891 */ 3892 3893 /* 3894 * We need this ioctl for efficient implementation of the 3895 * if_indextoname() function required by the IPv6 API. Without 3896 * it, we would have to search all the interfaces to find a 3897 * match. --pb 3898 */ 3899 3900 static int dev_ifname(struct net *net, struct ifreq __user *arg) 3901 { 3902 struct net_device *dev; 3903 struct ifreq ifr; 3904 3905 /* 3906 * Fetch the caller's info block. 3907 */ 3908 3909 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 3910 return -EFAULT; 3911 3912 rcu_read_lock(); 3913 dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex); 3914 if (!dev) { 3915 rcu_read_unlock(); 3916 return -ENODEV; 3917 } 3918 3919 strcpy(ifr.ifr_name, dev->name); 3920 rcu_read_unlock(); 3921 3922 if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) 3923 return -EFAULT; 3924 return 0; 3925 } 3926 3927 /* 3928 * Perform a SIOCGIFCONF call. This structure will change 3929 * size eventually, and there is nothing I can do about it. 3930 * Thus we will need a 'compatibility mode'. 3931 */ 3932 3933 static int dev_ifconf(struct net *net, char __user *arg) 3934 { 3935 struct ifconf ifc; 3936 struct net_device *dev; 3937 char __user *pos; 3938 int len; 3939 int total; 3940 int i; 3941 3942 /* 3943 * Fetch the caller's info block. 3944 */ 3945 3946 if (copy_from_user(&ifc, arg, sizeof(struct ifconf))) 3947 return -EFAULT; 3948 3949 pos = ifc.ifc_buf; 3950 len = ifc.ifc_len; 3951 3952 /* 3953 * Loop over the interfaces, and write an info block for each. 3954 */ 3955 3956 total = 0; 3957 for_each_netdev(net, dev) { 3958 for (i = 0; i < NPROTO; i++) { 3959 if (gifconf_list[i]) { 3960 int done; 3961 if (!pos) 3962 done = gifconf_list[i](dev, NULL, 0); 3963 else 3964 done = gifconf_list[i](dev, pos + total, 3965 len - total); 3966 if (done < 0) 3967 return -EFAULT; 3968 total += done; 3969 } 3970 } 3971 } 3972 3973 /* 3974 * All done. Write the updated control block back to the caller. 3975 */ 3976 ifc.ifc_len = total; 3977 3978 /* 3979 * Both BSD and Solaris return 0 here, so we do too. 3980 */ 3981 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0; 3982 } 3983 3984 #ifdef CONFIG_PROC_FS 3985 /* 3986 * This is invoked by the /proc filesystem handler to display a device 3987 * in detail. 3988 */ 3989 void *dev_seq_start(struct seq_file *seq, loff_t *pos) 3990 __acquires(RCU) 3991 { 3992 struct net *net = seq_file_net(seq); 3993 loff_t off; 3994 struct net_device *dev; 3995 3996 rcu_read_lock(); 3997 if (!*pos) 3998 return SEQ_START_TOKEN; 3999 4000 off = 1; 4001 for_each_netdev_rcu(net, dev) 4002 if (off++ == *pos) 4003 return dev; 4004 4005 return NULL; 4006 } 4007 4008 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4009 { 4010 struct net_device *dev = v; 4011 4012 if (v == SEQ_START_TOKEN) 4013 dev = first_net_device_rcu(seq_file_net(seq)); 4014 else 4015 dev = next_net_device_rcu(dev); 4016 4017 ++*pos; 4018 return dev; 4019 } 4020 4021 void dev_seq_stop(struct seq_file *seq, void *v) 4022 __releases(RCU) 4023 { 4024 rcu_read_unlock(); 4025 } 4026 4027 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev) 4028 { 4029 struct rtnl_link_stats64 temp; 4030 const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp); 4031 4032 seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu " 4033 "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n", 4034 dev->name, stats->rx_bytes, stats->rx_packets, 4035 stats->rx_errors, 4036 stats->rx_dropped + stats->rx_missed_errors, 4037 stats->rx_fifo_errors, 4038 stats->rx_length_errors + stats->rx_over_errors + 4039 stats->rx_crc_errors + stats->rx_frame_errors, 4040 stats->rx_compressed, stats->multicast, 4041 stats->tx_bytes, stats->tx_packets, 4042 stats->tx_errors, stats->tx_dropped, 4043 stats->tx_fifo_errors, stats->collisions, 4044 stats->tx_carrier_errors + 4045 stats->tx_aborted_errors + 4046 stats->tx_window_errors + 4047 stats->tx_heartbeat_errors, 4048 stats->tx_compressed); 4049 } 4050 4051 /* 4052 * Called from the PROCfs module. This now uses the new arbitrary sized 4053 * /proc/net interface to create /proc/net/dev 4054 */ 4055 static int dev_seq_show(struct seq_file *seq, void *v) 4056 { 4057 if (v == SEQ_START_TOKEN) 4058 seq_puts(seq, "Inter-| Receive " 4059 " | Transmit\n" 4060 " face |bytes packets errs drop fifo frame " 4061 "compressed multicast|bytes packets errs " 4062 "drop fifo colls carrier compressed\n"); 4063 else 4064 dev_seq_printf_stats(seq, v); 4065 return 0; 4066 } 4067 4068 static struct softnet_data *softnet_get_online(loff_t *pos) 4069 { 4070 struct softnet_data *sd = NULL; 4071 4072 while (*pos < nr_cpu_ids) 4073 if (cpu_online(*pos)) { 4074 sd = &per_cpu(softnet_data, *pos); 4075 break; 4076 } else 4077 ++*pos; 4078 return sd; 4079 } 4080 4081 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) 4082 { 4083 return softnet_get_online(pos); 4084 } 4085 4086 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4087 { 4088 ++*pos; 4089 return softnet_get_online(pos); 4090 } 4091 4092 static void softnet_seq_stop(struct seq_file *seq, void *v) 4093 { 4094 } 4095 4096 static int softnet_seq_show(struct seq_file *seq, void *v) 4097 { 4098 struct softnet_data *sd = v; 4099 4100 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 4101 sd->processed, sd->dropped, sd->time_squeeze, 0, 4102 0, 0, 0, 0, /* was fastroute */ 4103 sd->cpu_collision, sd->received_rps); 4104 return 0; 4105 } 4106 4107 static const struct seq_operations dev_seq_ops = { 4108 .start = dev_seq_start, 4109 .next = dev_seq_next, 4110 .stop = dev_seq_stop, 4111 .show = dev_seq_show, 4112 }; 4113 4114 static int dev_seq_open(struct inode *inode, struct file *file) 4115 { 4116 return seq_open_net(inode, file, &dev_seq_ops, 4117 sizeof(struct seq_net_private)); 4118 } 4119 4120 static const struct file_operations dev_seq_fops = { 4121 .owner = THIS_MODULE, 4122 .open = dev_seq_open, 4123 .read = seq_read, 4124 .llseek = seq_lseek, 4125 .release = seq_release_net, 4126 }; 4127 4128 static const struct seq_operations softnet_seq_ops = { 4129 .start = softnet_seq_start, 4130 .next = softnet_seq_next, 4131 .stop = softnet_seq_stop, 4132 .show = softnet_seq_show, 4133 }; 4134 4135 static int softnet_seq_open(struct inode *inode, struct file *file) 4136 { 4137 return seq_open(file, &softnet_seq_ops); 4138 } 4139 4140 static const struct file_operations softnet_seq_fops = { 4141 .owner = THIS_MODULE, 4142 .open = softnet_seq_open, 4143 .read = seq_read, 4144 .llseek = seq_lseek, 4145 .release = seq_release, 4146 }; 4147 4148 static void *ptype_get_idx(loff_t pos) 4149 { 4150 struct packet_type *pt = NULL; 4151 loff_t i = 0; 4152 int t; 4153 4154 list_for_each_entry_rcu(pt, &ptype_all, list) { 4155 if (i == pos) 4156 return pt; 4157 ++i; 4158 } 4159 4160 for (t = 0; t < PTYPE_HASH_SIZE; t++) { 4161 list_for_each_entry_rcu(pt, &ptype_base[t], list) { 4162 if (i == pos) 4163 return pt; 4164 ++i; 4165 } 4166 } 4167 return NULL; 4168 } 4169 4170 static void *ptype_seq_start(struct seq_file *seq, loff_t *pos) 4171 __acquires(RCU) 4172 { 4173 rcu_read_lock(); 4174 return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN; 4175 } 4176 4177 static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4178 { 4179 struct packet_type *pt; 4180 struct list_head *nxt; 4181 int hash; 4182 4183 ++*pos; 4184 if (v == SEQ_START_TOKEN) 4185 return ptype_get_idx(0); 4186 4187 pt = v; 4188 nxt = pt->list.next; 4189 if (pt->type == htons(ETH_P_ALL)) { 4190 if (nxt != &ptype_all) 4191 goto found; 4192 hash = 0; 4193 nxt = ptype_base[0].next; 4194 } else 4195 hash = ntohs(pt->type) & PTYPE_HASH_MASK; 4196 4197 while (nxt == &ptype_base[hash]) { 4198 if (++hash >= PTYPE_HASH_SIZE) 4199 return NULL; 4200 nxt = ptype_base[hash].next; 4201 } 4202 found: 4203 return list_entry(nxt, struct packet_type, list); 4204 } 4205 4206 static void ptype_seq_stop(struct seq_file *seq, void *v) 4207 __releases(RCU) 4208 { 4209 rcu_read_unlock(); 4210 } 4211 4212 static int ptype_seq_show(struct seq_file *seq, void *v) 4213 { 4214 struct packet_type *pt = v; 4215 4216 if (v == SEQ_START_TOKEN) 4217 seq_puts(seq, "Type Device Function\n"); 4218 else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) { 4219 if (pt->type == htons(ETH_P_ALL)) 4220 seq_puts(seq, "ALL "); 4221 else 4222 seq_printf(seq, "%04x", ntohs(pt->type)); 4223 4224 seq_printf(seq, " %-8s %pF\n", 4225 pt->dev ? pt->dev->name : "", pt->func); 4226 } 4227 4228 return 0; 4229 } 4230 4231 static const struct seq_operations ptype_seq_ops = { 4232 .start = ptype_seq_start, 4233 .next = ptype_seq_next, 4234 .stop = ptype_seq_stop, 4235 .show = ptype_seq_show, 4236 }; 4237 4238 static int ptype_seq_open(struct inode *inode, struct file *file) 4239 { 4240 return seq_open_net(inode, file, &ptype_seq_ops, 4241 sizeof(struct seq_net_private)); 4242 } 4243 4244 static const struct file_operations ptype_seq_fops = { 4245 .owner = THIS_MODULE, 4246 .open = ptype_seq_open, 4247 .read = seq_read, 4248 .llseek = seq_lseek, 4249 .release = seq_release_net, 4250 }; 4251 4252 4253 static int __net_init dev_proc_net_init(struct net *net) 4254 { 4255 int rc = -ENOMEM; 4256 4257 if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops)) 4258 goto out; 4259 if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops)) 4260 goto out_dev; 4261 if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops)) 4262 goto out_softnet; 4263 4264 if (wext_proc_init(net)) 4265 goto out_ptype; 4266 rc = 0; 4267 out: 4268 return rc; 4269 out_ptype: 4270 proc_net_remove(net, "ptype"); 4271 out_softnet: 4272 proc_net_remove(net, "softnet_stat"); 4273 out_dev: 4274 proc_net_remove(net, "dev"); 4275 goto out; 4276 } 4277 4278 static void __net_exit dev_proc_net_exit(struct net *net) 4279 { 4280 wext_proc_exit(net); 4281 4282 proc_net_remove(net, "ptype"); 4283 proc_net_remove(net, "softnet_stat"); 4284 proc_net_remove(net, "dev"); 4285 } 4286 4287 static struct pernet_operations __net_initdata dev_proc_ops = { 4288 .init = dev_proc_net_init, 4289 .exit = dev_proc_net_exit, 4290 }; 4291 4292 static int __init dev_proc_init(void) 4293 { 4294 return register_pernet_subsys(&dev_proc_ops); 4295 } 4296 #else 4297 #define dev_proc_init() 0 4298 #endif /* CONFIG_PROC_FS */ 4299 4300 4301 /** 4302 * netdev_set_master - set up master pointer 4303 * @slave: slave device 4304 * @master: new master device 4305 * 4306 * Changes the master device of the slave. Pass %NULL to break the 4307 * bonding. The caller must hold the RTNL semaphore. On a failure 4308 * a negative errno code is returned. On success the reference counts 4309 * are adjusted and the function returns zero. 4310 */ 4311 int netdev_set_master(struct net_device *slave, struct net_device *master) 4312 { 4313 struct net_device *old = slave->master; 4314 4315 ASSERT_RTNL(); 4316 4317 if (master) { 4318 if (old) 4319 return -EBUSY; 4320 dev_hold(master); 4321 } 4322 4323 slave->master = master; 4324 4325 if (old) 4326 dev_put(old); 4327 return 0; 4328 } 4329 EXPORT_SYMBOL(netdev_set_master); 4330 4331 /** 4332 * netdev_set_bond_master - set up bonding master/slave pair 4333 * @slave: slave device 4334 * @master: new master device 4335 * 4336 * Changes the master device of the slave. Pass %NULL to break the 4337 * bonding. The caller must hold the RTNL semaphore. On a failure 4338 * a negative errno code is returned. On success %RTM_NEWLINK is sent 4339 * to the routing socket and the function returns zero. 4340 */ 4341 int netdev_set_bond_master(struct net_device *slave, struct net_device *master) 4342 { 4343 int err; 4344 4345 ASSERT_RTNL(); 4346 4347 err = netdev_set_master(slave, master); 4348 if (err) 4349 return err; 4350 if (master) 4351 slave->flags |= IFF_SLAVE; 4352 else 4353 slave->flags &= ~IFF_SLAVE; 4354 4355 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE); 4356 return 0; 4357 } 4358 EXPORT_SYMBOL(netdev_set_bond_master); 4359 4360 static void dev_change_rx_flags(struct net_device *dev, int flags) 4361 { 4362 const struct net_device_ops *ops = dev->netdev_ops; 4363 4364 if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags) 4365 ops->ndo_change_rx_flags(dev, flags); 4366 } 4367 4368 static int __dev_set_promiscuity(struct net_device *dev, int inc) 4369 { 4370 unsigned short old_flags = dev->flags; 4371 uid_t uid; 4372 gid_t gid; 4373 4374 ASSERT_RTNL(); 4375 4376 dev->flags |= IFF_PROMISC; 4377 dev->promiscuity += inc; 4378 if (dev->promiscuity == 0) { 4379 /* 4380 * Avoid overflow. 4381 * If inc causes overflow, untouch promisc and return error. 4382 */ 4383 if (inc < 0) 4384 dev->flags &= ~IFF_PROMISC; 4385 else { 4386 dev->promiscuity -= inc; 4387 printk(KERN_WARNING "%s: promiscuity touches roof, " 4388 "set promiscuity failed, promiscuity feature " 4389 "of device might be broken.\n", dev->name); 4390 return -EOVERFLOW; 4391 } 4392 } 4393 if (dev->flags != old_flags) { 4394 printk(KERN_INFO "device %s %s promiscuous mode\n", 4395 dev->name, (dev->flags & IFF_PROMISC) ? "entered" : 4396 "left"); 4397 if (audit_enabled) { 4398 current_uid_gid(&uid, &gid); 4399 audit_log(current->audit_context, GFP_ATOMIC, 4400 AUDIT_ANOM_PROMISCUOUS, 4401 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 4402 dev->name, (dev->flags & IFF_PROMISC), 4403 (old_flags & IFF_PROMISC), 4404 audit_get_loginuid(current), 4405 uid, gid, 4406 audit_get_sessionid(current)); 4407 } 4408 4409 dev_change_rx_flags(dev, IFF_PROMISC); 4410 } 4411 return 0; 4412 } 4413 4414 /** 4415 * dev_set_promiscuity - update promiscuity count on a device 4416 * @dev: device 4417 * @inc: modifier 4418 * 4419 * Add or remove promiscuity from a device. While the count in the device 4420 * remains above zero the interface remains promiscuous. Once it hits zero 4421 * the device reverts back to normal filtering operation. A negative inc 4422 * value is used to drop promiscuity on the device. 4423 * Return 0 if successful or a negative errno code on error. 4424 */ 4425 int dev_set_promiscuity(struct net_device *dev, int inc) 4426 { 4427 unsigned short old_flags = dev->flags; 4428 int err; 4429 4430 err = __dev_set_promiscuity(dev, inc); 4431 if (err < 0) 4432 return err; 4433 if (dev->flags != old_flags) 4434 dev_set_rx_mode(dev); 4435 return err; 4436 } 4437 EXPORT_SYMBOL(dev_set_promiscuity); 4438 4439 /** 4440 * dev_set_allmulti - update allmulti count on a device 4441 * @dev: device 4442 * @inc: modifier 4443 * 4444 * Add or remove reception of all multicast frames to a device. While the 4445 * count in the device remains above zero the interface remains listening 4446 * to all interfaces. Once it hits zero the device reverts back to normal 4447 * filtering operation. A negative @inc value is used to drop the counter 4448 * when releasing a resource needing all multicasts. 4449 * Return 0 if successful or a negative errno code on error. 4450 */ 4451 4452 int dev_set_allmulti(struct net_device *dev, int inc) 4453 { 4454 unsigned short old_flags = dev->flags; 4455 4456 ASSERT_RTNL(); 4457 4458 dev->flags |= IFF_ALLMULTI; 4459 dev->allmulti += inc; 4460 if (dev->allmulti == 0) { 4461 /* 4462 * Avoid overflow. 4463 * If inc causes overflow, untouch allmulti and return error. 4464 */ 4465 if (inc < 0) 4466 dev->flags &= ~IFF_ALLMULTI; 4467 else { 4468 dev->allmulti -= inc; 4469 printk(KERN_WARNING "%s: allmulti touches roof, " 4470 "set allmulti failed, allmulti feature of " 4471 "device might be broken.\n", dev->name); 4472 return -EOVERFLOW; 4473 } 4474 } 4475 if (dev->flags ^ old_flags) { 4476 dev_change_rx_flags(dev, IFF_ALLMULTI); 4477 dev_set_rx_mode(dev); 4478 } 4479 return 0; 4480 } 4481 EXPORT_SYMBOL(dev_set_allmulti); 4482 4483 /* 4484 * Upload unicast and multicast address lists to device and 4485 * configure RX filtering. When the device doesn't support unicast 4486 * filtering it is put in promiscuous mode while unicast addresses 4487 * are present. 4488 */ 4489 void __dev_set_rx_mode(struct net_device *dev) 4490 { 4491 const struct net_device_ops *ops = dev->netdev_ops; 4492 4493 /* dev_open will call this function so the list will stay sane. */ 4494 if (!(dev->flags&IFF_UP)) 4495 return; 4496 4497 if (!netif_device_present(dev)) 4498 return; 4499 4500 if (ops->ndo_set_rx_mode) 4501 ops->ndo_set_rx_mode(dev); 4502 else { 4503 /* Unicast addresses changes may only happen under the rtnl, 4504 * therefore calling __dev_set_promiscuity here is safe. 4505 */ 4506 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 4507 __dev_set_promiscuity(dev, 1); 4508 dev->uc_promisc = true; 4509 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 4510 __dev_set_promiscuity(dev, -1); 4511 dev->uc_promisc = false; 4512 } 4513 4514 if (ops->ndo_set_multicast_list) 4515 ops->ndo_set_multicast_list(dev); 4516 } 4517 } 4518 4519 void dev_set_rx_mode(struct net_device *dev) 4520 { 4521 netif_addr_lock_bh(dev); 4522 __dev_set_rx_mode(dev); 4523 netif_addr_unlock_bh(dev); 4524 } 4525 4526 /** 4527 * dev_ethtool_get_settings - call device's ethtool_ops::get_settings() 4528 * @dev: device 4529 * @cmd: memory area for ethtool_ops::get_settings() result 4530 * 4531 * The cmd arg is initialized properly (cleared and 4532 * ethtool_cmd::cmd field set to ETHTOOL_GSET). 4533 * 4534 * Return device's ethtool_ops::get_settings() result value or 4535 * -EOPNOTSUPP when device doesn't expose 4536 * ethtool_ops::get_settings() operation. 4537 */ 4538 int dev_ethtool_get_settings(struct net_device *dev, 4539 struct ethtool_cmd *cmd) 4540 { 4541 if (!dev->ethtool_ops || !dev->ethtool_ops->get_settings) 4542 return -EOPNOTSUPP; 4543 4544 memset(cmd, 0, sizeof(struct ethtool_cmd)); 4545 cmd->cmd = ETHTOOL_GSET; 4546 return dev->ethtool_ops->get_settings(dev, cmd); 4547 } 4548 EXPORT_SYMBOL(dev_ethtool_get_settings); 4549 4550 /** 4551 * dev_get_flags - get flags reported to userspace 4552 * @dev: device 4553 * 4554 * Get the combination of flag bits exported through APIs to userspace. 4555 */ 4556 unsigned dev_get_flags(const struct net_device *dev) 4557 { 4558 unsigned flags; 4559 4560 flags = (dev->flags & ~(IFF_PROMISC | 4561 IFF_ALLMULTI | 4562 IFF_RUNNING | 4563 IFF_LOWER_UP | 4564 IFF_DORMANT)) | 4565 (dev->gflags & (IFF_PROMISC | 4566 IFF_ALLMULTI)); 4567 4568 if (netif_running(dev)) { 4569 if (netif_oper_up(dev)) 4570 flags |= IFF_RUNNING; 4571 if (netif_carrier_ok(dev)) 4572 flags |= IFF_LOWER_UP; 4573 if (netif_dormant(dev)) 4574 flags |= IFF_DORMANT; 4575 } 4576 4577 return flags; 4578 } 4579 EXPORT_SYMBOL(dev_get_flags); 4580 4581 int __dev_change_flags(struct net_device *dev, unsigned int flags) 4582 { 4583 int old_flags = dev->flags; 4584 int ret; 4585 4586 ASSERT_RTNL(); 4587 4588 /* 4589 * Set the flags on our device. 4590 */ 4591 4592 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 4593 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 4594 IFF_AUTOMEDIA)) | 4595 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 4596 IFF_ALLMULTI)); 4597 4598 /* 4599 * Load in the correct multicast list now the flags have changed. 4600 */ 4601 4602 if ((old_flags ^ flags) & IFF_MULTICAST) 4603 dev_change_rx_flags(dev, IFF_MULTICAST); 4604 4605 dev_set_rx_mode(dev); 4606 4607 /* 4608 * Have we downed the interface. We handle IFF_UP ourselves 4609 * according to user attempts to set it, rather than blindly 4610 * setting it. 4611 */ 4612 4613 ret = 0; 4614 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ 4615 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev); 4616 4617 if (!ret) 4618 dev_set_rx_mode(dev); 4619 } 4620 4621 if ((flags ^ dev->gflags) & IFF_PROMISC) { 4622 int inc = (flags & IFF_PROMISC) ? 1 : -1; 4623 4624 dev->gflags ^= IFF_PROMISC; 4625 dev_set_promiscuity(dev, inc); 4626 } 4627 4628 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 4629 is important. Some (broken) drivers set IFF_PROMISC, when 4630 IFF_ALLMULTI is requested not asking us and not reporting. 4631 */ 4632 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 4633 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 4634 4635 dev->gflags ^= IFF_ALLMULTI; 4636 dev_set_allmulti(dev, inc); 4637 } 4638 4639 return ret; 4640 } 4641 4642 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags) 4643 { 4644 unsigned int changes = dev->flags ^ old_flags; 4645 4646 if (changes & IFF_UP) { 4647 if (dev->flags & IFF_UP) 4648 call_netdevice_notifiers(NETDEV_UP, dev); 4649 else 4650 call_netdevice_notifiers(NETDEV_DOWN, dev); 4651 } 4652 4653 if (dev->flags & IFF_UP && 4654 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) 4655 call_netdevice_notifiers(NETDEV_CHANGE, dev); 4656 } 4657 4658 /** 4659 * dev_change_flags - change device settings 4660 * @dev: device 4661 * @flags: device state flags 4662 * 4663 * Change settings on device based state flags. The flags are 4664 * in the userspace exported format. 4665 */ 4666 int dev_change_flags(struct net_device *dev, unsigned flags) 4667 { 4668 int ret, changes; 4669 int old_flags = dev->flags; 4670 4671 ret = __dev_change_flags(dev, flags); 4672 if (ret < 0) 4673 return ret; 4674 4675 changes = old_flags ^ dev->flags; 4676 if (changes) 4677 rtmsg_ifinfo(RTM_NEWLINK, dev, changes); 4678 4679 __dev_notify_flags(dev, old_flags); 4680 return ret; 4681 } 4682 EXPORT_SYMBOL(dev_change_flags); 4683 4684 /** 4685 * dev_set_mtu - Change maximum transfer unit 4686 * @dev: device 4687 * @new_mtu: new transfer unit 4688 * 4689 * Change the maximum transfer size of the network device. 4690 */ 4691 int dev_set_mtu(struct net_device *dev, int new_mtu) 4692 { 4693 const struct net_device_ops *ops = dev->netdev_ops; 4694 int err; 4695 4696 if (new_mtu == dev->mtu) 4697 return 0; 4698 4699 /* MTU must be positive. */ 4700 if (new_mtu < 0) 4701 return -EINVAL; 4702 4703 if (!netif_device_present(dev)) 4704 return -ENODEV; 4705 4706 err = 0; 4707 if (ops->ndo_change_mtu) 4708 err = ops->ndo_change_mtu(dev, new_mtu); 4709 else 4710 dev->mtu = new_mtu; 4711 4712 if (!err && dev->flags & IFF_UP) 4713 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); 4714 return err; 4715 } 4716 EXPORT_SYMBOL(dev_set_mtu); 4717 4718 /** 4719 * dev_set_group - Change group this device belongs to 4720 * @dev: device 4721 * @new_group: group this device should belong to 4722 */ 4723 void dev_set_group(struct net_device *dev, int new_group) 4724 { 4725 dev->group = new_group; 4726 } 4727 EXPORT_SYMBOL(dev_set_group); 4728 4729 /** 4730 * dev_set_mac_address - Change Media Access Control Address 4731 * @dev: device 4732 * @sa: new address 4733 * 4734 * Change the hardware (MAC) address of the device 4735 */ 4736 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) 4737 { 4738 const struct net_device_ops *ops = dev->netdev_ops; 4739 int err; 4740 4741 if (!ops->ndo_set_mac_address) 4742 return -EOPNOTSUPP; 4743 if (sa->sa_family != dev->type) 4744 return -EINVAL; 4745 if (!netif_device_present(dev)) 4746 return -ENODEV; 4747 err = ops->ndo_set_mac_address(dev, sa); 4748 if (!err) 4749 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4750 return err; 4751 } 4752 EXPORT_SYMBOL(dev_set_mac_address); 4753 4754 /* 4755 * Perform the SIOCxIFxxx calls, inside rcu_read_lock() 4756 */ 4757 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd) 4758 { 4759 int err; 4760 struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name); 4761 4762 if (!dev) 4763 return -ENODEV; 4764 4765 switch (cmd) { 4766 case SIOCGIFFLAGS: /* Get interface flags */ 4767 ifr->ifr_flags = (short) dev_get_flags(dev); 4768 return 0; 4769 4770 case SIOCGIFMETRIC: /* Get the metric on the interface 4771 (currently unused) */ 4772 ifr->ifr_metric = 0; 4773 return 0; 4774 4775 case SIOCGIFMTU: /* Get the MTU of a device */ 4776 ifr->ifr_mtu = dev->mtu; 4777 return 0; 4778 4779 case SIOCGIFHWADDR: 4780 if (!dev->addr_len) 4781 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data); 4782 else 4783 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr, 4784 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4785 ifr->ifr_hwaddr.sa_family = dev->type; 4786 return 0; 4787 4788 case SIOCGIFSLAVE: 4789 err = -EINVAL; 4790 break; 4791 4792 case SIOCGIFMAP: 4793 ifr->ifr_map.mem_start = dev->mem_start; 4794 ifr->ifr_map.mem_end = dev->mem_end; 4795 ifr->ifr_map.base_addr = dev->base_addr; 4796 ifr->ifr_map.irq = dev->irq; 4797 ifr->ifr_map.dma = dev->dma; 4798 ifr->ifr_map.port = dev->if_port; 4799 return 0; 4800 4801 case SIOCGIFINDEX: 4802 ifr->ifr_ifindex = dev->ifindex; 4803 return 0; 4804 4805 case SIOCGIFTXQLEN: 4806 ifr->ifr_qlen = dev->tx_queue_len; 4807 return 0; 4808 4809 default: 4810 /* dev_ioctl() should ensure this case 4811 * is never reached 4812 */ 4813 WARN_ON(1); 4814 err = -ENOTTY; 4815 break; 4816 4817 } 4818 return err; 4819 } 4820 4821 /* 4822 * Perform the SIOCxIFxxx calls, inside rtnl_lock() 4823 */ 4824 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd) 4825 { 4826 int err; 4827 struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name); 4828 const struct net_device_ops *ops; 4829 4830 if (!dev) 4831 return -ENODEV; 4832 4833 ops = dev->netdev_ops; 4834 4835 switch (cmd) { 4836 case SIOCSIFFLAGS: /* Set interface flags */ 4837 return dev_change_flags(dev, ifr->ifr_flags); 4838 4839 case SIOCSIFMETRIC: /* Set the metric on the interface 4840 (currently unused) */ 4841 return -EOPNOTSUPP; 4842 4843 case SIOCSIFMTU: /* Set the MTU of a device */ 4844 return dev_set_mtu(dev, ifr->ifr_mtu); 4845 4846 case SIOCSIFHWADDR: 4847 return dev_set_mac_address(dev, &ifr->ifr_hwaddr); 4848 4849 case SIOCSIFHWBROADCAST: 4850 if (ifr->ifr_hwaddr.sa_family != dev->type) 4851 return -EINVAL; 4852 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data, 4853 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4854 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4855 return 0; 4856 4857 case SIOCSIFMAP: 4858 if (ops->ndo_set_config) { 4859 if (!netif_device_present(dev)) 4860 return -ENODEV; 4861 return ops->ndo_set_config(dev, &ifr->ifr_map); 4862 } 4863 return -EOPNOTSUPP; 4864 4865 case SIOCADDMULTI: 4866 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4867 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4868 return -EINVAL; 4869 if (!netif_device_present(dev)) 4870 return -ENODEV; 4871 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data); 4872 4873 case SIOCDELMULTI: 4874 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4875 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4876 return -EINVAL; 4877 if (!netif_device_present(dev)) 4878 return -ENODEV; 4879 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data); 4880 4881 case SIOCSIFTXQLEN: 4882 if (ifr->ifr_qlen < 0) 4883 return -EINVAL; 4884 dev->tx_queue_len = ifr->ifr_qlen; 4885 return 0; 4886 4887 case SIOCSIFNAME: 4888 ifr->ifr_newname[IFNAMSIZ-1] = '\0'; 4889 return dev_change_name(dev, ifr->ifr_newname); 4890 4891 /* 4892 * Unknown or private ioctl 4893 */ 4894 default: 4895 if ((cmd >= SIOCDEVPRIVATE && 4896 cmd <= SIOCDEVPRIVATE + 15) || 4897 cmd == SIOCBONDENSLAVE || 4898 cmd == SIOCBONDRELEASE || 4899 cmd == SIOCBONDSETHWADDR || 4900 cmd == SIOCBONDSLAVEINFOQUERY || 4901 cmd == SIOCBONDINFOQUERY || 4902 cmd == SIOCBONDCHANGEACTIVE || 4903 cmd == SIOCGMIIPHY || 4904 cmd == SIOCGMIIREG || 4905 cmd == SIOCSMIIREG || 4906 cmd == SIOCBRADDIF || 4907 cmd == SIOCBRDELIF || 4908 cmd == SIOCSHWTSTAMP || 4909 cmd == SIOCWANDEV) { 4910 err = -EOPNOTSUPP; 4911 if (ops->ndo_do_ioctl) { 4912 if (netif_device_present(dev)) 4913 err = ops->ndo_do_ioctl(dev, ifr, cmd); 4914 else 4915 err = -ENODEV; 4916 } 4917 } else 4918 err = -EINVAL; 4919 4920 } 4921 return err; 4922 } 4923 4924 /* 4925 * This function handles all "interface"-type I/O control requests. The actual 4926 * 'doing' part of this is dev_ifsioc above. 4927 */ 4928 4929 /** 4930 * dev_ioctl - network device ioctl 4931 * @net: the applicable net namespace 4932 * @cmd: command to issue 4933 * @arg: pointer to a struct ifreq in user space 4934 * 4935 * Issue ioctl functions to devices. This is normally called by the 4936 * user space syscall interfaces but can sometimes be useful for 4937 * other purposes. The return value is the return from the syscall if 4938 * positive or a negative errno code on error. 4939 */ 4940 4941 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg) 4942 { 4943 struct ifreq ifr; 4944 int ret; 4945 char *colon; 4946 4947 /* One special case: SIOCGIFCONF takes ifconf argument 4948 and requires shared lock, because it sleeps writing 4949 to user space. 4950 */ 4951 4952 if (cmd == SIOCGIFCONF) { 4953 rtnl_lock(); 4954 ret = dev_ifconf(net, (char __user *) arg); 4955 rtnl_unlock(); 4956 return ret; 4957 } 4958 if (cmd == SIOCGIFNAME) 4959 return dev_ifname(net, (struct ifreq __user *)arg); 4960 4961 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 4962 return -EFAULT; 4963 4964 ifr.ifr_name[IFNAMSIZ-1] = 0; 4965 4966 colon = strchr(ifr.ifr_name, ':'); 4967 if (colon) 4968 *colon = 0; 4969 4970 /* 4971 * See which interface the caller is talking about. 4972 */ 4973 4974 switch (cmd) { 4975 /* 4976 * These ioctl calls: 4977 * - can be done by all. 4978 * - atomic and do not require locking. 4979 * - return a value 4980 */ 4981 case SIOCGIFFLAGS: 4982 case SIOCGIFMETRIC: 4983 case SIOCGIFMTU: 4984 case SIOCGIFHWADDR: 4985 case SIOCGIFSLAVE: 4986 case SIOCGIFMAP: 4987 case SIOCGIFINDEX: 4988 case SIOCGIFTXQLEN: 4989 dev_load(net, ifr.ifr_name); 4990 rcu_read_lock(); 4991 ret = dev_ifsioc_locked(net, &ifr, cmd); 4992 rcu_read_unlock(); 4993 if (!ret) { 4994 if (colon) 4995 *colon = ':'; 4996 if (copy_to_user(arg, &ifr, 4997 sizeof(struct ifreq))) 4998 ret = -EFAULT; 4999 } 5000 return ret; 5001 5002 case SIOCETHTOOL: 5003 dev_load(net, ifr.ifr_name); 5004 rtnl_lock(); 5005 ret = dev_ethtool(net, &ifr); 5006 rtnl_unlock(); 5007 if (!ret) { 5008 if (colon) 5009 *colon = ':'; 5010 if (copy_to_user(arg, &ifr, 5011 sizeof(struct ifreq))) 5012 ret = -EFAULT; 5013 } 5014 return ret; 5015 5016 /* 5017 * These ioctl calls: 5018 * - require superuser power. 5019 * - require strict serialization. 5020 * - return a value 5021 */ 5022 case SIOCGMIIPHY: 5023 case SIOCGMIIREG: 5024 case SIOCSIFNAME: 5025 if (!capable(CAP_NET_ADMIN)) 5026 return -EPERM; 5027 dev_load(net, ifr.ifr_name); 5028 rtnl_lock(); 5029 ret = dev_ifsioc(net, &ifr, cmd); 5030 rtnl_unlock(); 5031 if (!ret) { 5032 if (colon) 5033 *colon = ':'; 5034 if (copy_to_user(arg, &ifr, 5035 sizeof(struct ifreq))) 5036 ret = -EFAULT; 5037 } 5038 return ret; 5039 5040 /* 5041 * These ioctl calls: 5042 * - require superuser power. 5043 * - require strict serialization. 5044 * - do not return a value 5045 */ 5046 case SIOCSIFFLAGS: 5047 case SIOCSIFMETRIC: 5048 case SIOCSIFMTU: 5049 case SIOCSIFMAP: 5050 case SIOCSIFHWADDR: 5051 case SIOCSIFSLAVE: 5052 case SIOCADDMULTI: 5053 case SIOCDELMULTI: 5054 case SIOCSIFHWBROADCAST: 5055 case SIOCSIFTXQLEN: 5056 case SIOCSMIIREG: 5057 case SIOCBONDENSLAVE: 5058 case SIOCBONDRELEASE: 5059 case SIOCBONDSETHWADDR: 5060 case SIOCBONDCHANGEACTIVE: 5061 case SIOCBRADDIF: 5062 case SIOCBRDELIF: 5063 case SIOCSHWTSTAMP: 5064 if (!capable(CAP_NET_ADMIN)) 5065 return -EPERM; 5066 /* fall through */ 5067 case SIOCBONDSLAVEINFOQUERY: 5068 case SIOCBONDINFOQUERY: 5069 dev_load(net, ifr.ifr_name); 5070 rtnl_lock(); 5071 ret = dev_ifsioc(net, &ifr, cmd); 5072 rtnl_unlock(); 5073 return ret; 5074 5075 case SIOCGIFMEM: 5076 /* Get the per device memory space. We can add this but 5077 * currently do not support it */ 5078 case SIOCSIFMEM: 5079 /* Set the per device memory buffer space. 5080 * Not applicable in our case */ 5081 case SIOCSIFLINK: 5082 return -ENOTTY; 5083 5084 /* 5085 * Unknown or private ioctl. 5086 */ 5087 default: 5088 if (cmd == SIOCWANDEV || 5089 (cmd >= SIOCDEVPRIVATE && 5090 cmd <= SIOCDEVPRIVATE + 15)) { 5091 dev_load(net, ifr.ifr_name); 5092 rtnl_lock(); 5093 ret = dev_ifsioc(net, &ifr, cmd); 5094 rtnl_unlock(); 5095 if (!ret && copy_to_user(arg, &ifr, 5096 sizeof(struct ifreq))) 5097 ret = -EFAULT; 5098 return ret; 5099 } 5100 /* Take care of Wireless Extensions */ 5101 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) 5102 return wext_handle_ioctl(net, &ifr, cmd, arg); 5103 return -ENOTTY; 5104 } 5105 } 5106 5107 5108 /** 5109 * dev_new_index - allocate an ifindex 5110 * @net: the applicable net namespace 5111 * 5112 * Returns a suitable unique value for a new device interface 5113 * number. The caller must hold the rtnl semaphore or the 5114 * dev_base_lock to be sure it remains unique. 5115 */ 5116 static int dev_new_index(struct net *net) 5117 { 5118 static int ifindex; 5119 for (;;) { 5120 if (++ifindex <= 0) 5121 ifindex = 1; 5122 if (!__dev_get_by_index(net, ifindex)) 5123 return ifindex; 5124 } 5125 } 5126 5127 /* Delayed registration/unregisteration */ 5128 static LIST_HEAD(net_todo_list); 5129 5130 static void net_set_todo(struct net_device *dev) 5131 { 5132 list_add_tail(&dev->todo_list, &net_todo_list); 5133 } 5134 5135 static void rollback_registered_many(struct list_head *head) 5136 { 5137 struct net_device *dev, *tmp; 5138 5139 BUG_ON(dev_boot_phase); 5140 ASSERT_RTNL(); 5141 5142 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 5143 /* Some devices call without registering 5144 * for initialization unwind. Remove those 5145 * devices and proceed with the remaining. 5146 */ 5147 if (dev->reg_state == NETREG_UNINITIALIZED) { 5148 pr_debug("unregister_netdevice: device %s/%p never " 5149 "was registered\n", dev->name, dev); 5150 5151 WARN_ON(1); 5152 list_del(&dev->unreg_list); 5153 continue; 5154 } 5155 dev->dismantle = true; 5156 BUG_ON(dev->reg_state != NETREG_REGISTERED); 5157 } 5158 5159 /* If device is running, close it first. */ 5160 dev_close_many(head); 5161 5162 list_for_each_entry(dev, head, unreg_list) { 5163 /* And unlink it from device chain. */ 5164 unlist_netdevice(dev); 5165 5166 dev->reg_state = NETREG_UNREGISTERING; 5167 } 5168 5169 synchronize_net(); 5170 5171 list_for_each_entry(dev, head, unreg_list) { 5172 /* Shutdown queueing discipline. */ 5173 dev_shutdown(dev); 5174 5175 5176 /* Notify protocols, that we are about to destroy 5177 this device. They should clean all the things. 5178 */ 5179 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5180 5181 if (!dev->rtnl_link_ops || 5182 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 5183 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U); 5184 5185 /* 5186 * Flush the unicast and multicast chains 5187 */ 5188 dev_uc_flush(dev); 5189 dev_mc_flush(dev); 5190 5191 if (dev->netdev_ops->ndo_uninit) 5192 dev->netdev_ops->ndo_uninit(dev); 5193 5194 /* Notifier chain MUST detach us from master device. */ 5195 WARN_ON(dev->master); 5196 5197 /* Remove entries from kobject tree */ 5198 netdev_unregister_kobject(dev); 5199 } 5200 5201 /* Process any work delayed until the end of the batch */ 5202 dev = list_first_entry(head, struct net_device, unreg_list); 5203 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 5204 5205 rcu_barrier(); 5206 5207 list_for_each_entry(dev, head, unreg_list) 5208 dev_put(dev); 5209 } 5210 5211 static void rollback_registered(struct net_device *dev) 5212 { 5213 LIST_HEAD(single); 5214 5215 list_add(&dev->unreg_list, &single); 5216 rollback_registered_many(&single); 5217 list_del(&single); 5218 } 5219 5220 static u32 netdev_fix_features(struct net_device *dev, u32 features) 5221 { 5222 /* Fix illegal checksum combinations */ 5223 if ((features & NETIF_F_HW_CSUM) && 5224 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5225 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 5226 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 5227 } 5228 5229 if ((features & NETIF_F_NO_CSUM) && 5230 (features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5231 netdev_warn(dev, "mixed no checksumming and other settings.\n"); 5232 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM); 5233 } 5234 5235 /* Fix illegal SG+CSUM combinations. */ 5236 if ((features & NETIF_F_SG) && 5237 !(features & NETIF_F_ALL_CSUM)) { 5238 netdev_dbg(dev, 5239 "Dropping NETIF_F_SG since no checksum feature.\n"); 5240 features &= ~NETIF_F_SG; 5241 } 5242 5243 /* TSO requires that SG is present as well. */ 5244 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 5245 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 5246 features &= ~NETIF_F_ALL_TSO; 5247 } 5248 5249 /* TSO ECN requires that TSO is present as well. */ 5250 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 5251 features &= ~NETIF_F_TSO_ECN; 5252 5253 /* Software GSO depends on SG. */ 5254 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 5255 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 5256 features &= ~NETIF_F_GSO; 5257 } 5258 5259 /* UFO needs SG and checksumming */ 5260 if (features & NETIF_F_UFO) { 5261 /* maybe split UFO into V4 and V6? */ 5262 if (!((features & NETIF_F_GEN_CSUM) || 5263 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM)) 5264 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 5265 netdev_dbg(dev, 5266 "Dropping NETIF_F_UFO since no checksum offload features.\n"); 5267 features &= ~NETIF_F_UFO; 5268 } 5269 5270 if (!(features & NETIF_F_SG)) { 5271 netdev_dbg(dev, 5272 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n"); 5273 features &= ~NETIF_F_UFO; 5274 } 5275 } 5276 5277 return features; 5278 } 5279 5280 int __netdev_update_features(struct net_device *dev) 5281 { 5282 u32 features; 5283 int err = 0; 5284 5285 ASSERT_RTNL(); 5286 5287 features = netdev_get_wanted_features(dev); 5288 5289 if (dev->netdev_ops->ndo_fix_features) 5290 features = dev->netdev_ops->ndo_fix_features(dev, features); 5291 5292 /* driver might be less strict about feature dependencies */ 5293 features = netdev_fix_features(dev, features); 5294 5295 if (dev->features == features) 5296 return 0; 5297 5298 netdev_dbg(dev, "Features changed: 0x%08x -> 0x%08x\n", 5299 dev->features, features); 5300 5301 if (dev->netdev_ops->ndo_set_features) 5302 err = dev->netdev_ops->ndo_set_features(dev, features); 5303 5304 if (unlikely(err < 0)) { 5305 netdev_err(dev, 5306 "set_features() failed (%d); wanted 0x%08x, left 0x%08x\n", 5307 err, features, dev->features); 5308 return -1; 5309 } 5310 5311 if (!err) 5312 dev->features = features; 5313 5314 return 1; 5315 } 5316 5317 /** 5318 * netdev_update_features - recalculate device features 5319 * @dev: the device to check 5320 * 5321 * Recalculate dev->features set and send notifications if it 5322 * has changed. Should be called after driver or hardware dependent 5323 * conditions might have changed that influence the features. 5324 */ 5325 void netdev_update_features(struct net_device *dev) 5326 { 5327 if (__netdev_update_features(dev)) 5328 netdev_features_change(dev); 5329 } 5330 EXPORT_SYMBOL(netdev_update_features); 5331 5332 /** 5333 * netdev_change_features - recalculate device features 5334 * @dev: the device to check 5335 * 5336 * Recalculate dev->features set and send notifications even 5337 * if they have not changed. Should be called instead of 5338 * netdev_update_features() if also dev->vlan_features might 5339 * have changed to allow the changes to be propagated to stacked 5340 * VLAN devices. 5341 */ 5342 void netdev_change_features(struct net_device *dev) 5343 { 5344 __netdev_update_features(dev); 5345 netdev_features_change(dev); 5346 } 5347 EXPORT_SYMBOL(netdev_change_features); 5348 5349 /** 5350 * netif_stacked_transfer_operstate - transfer operstate 5351 * @rootdev: the root or lower level device to transfer state from 5352 * @dev: the device to transfer operstate to 5353 * 5354 * Transfer operational state from root to device. This is normally 5355 * called when a stacking relationship exists between the root 5356 * device and the device(a leaf device). 5357 */ 5358 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 5359 struct net_device *dev) 5360 { 5361 if (rootdev->operstate == IF_OPER_DORMANT) 5362 netif_dormant_on(dev); 5363 else 5364 netif_dormant_off(dev); 5365 5366 if (netif_carrier_ok(rootdev)) { 5367 if (!netif_carrier_ok(dev)) 5368 netif_carrier_on(dev); 5369 } else { 5370 if (netif_carrier_ok(dev)) 5371 netif_carrier_off(dev); 5372 } 5373 } 5374 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 5375 5376 #ifdef CONFIG_RPS 5377 static int netif_alloc_rx_queues(struct net_device *dev) 5378 { 5379 unsigned int i, count = dev->num_rx_queues; 5380 struct netdev_rx_queue *rx; 5381 5382 BUG_ON(count < 1); 5383 5384 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL); 5385 if (!rx) { 5386 pr_err("netdev: Unable to allocate %u rx queues.\n", count); 5387 return -ENOMEM; 5388 } 5389 dev->_rx = rx; 5390 5391 for (i = 0; i < count; i++) 5392 rx[i].dev = dev; 5393 return 0; 5394 } 5395 #endif 5396 5397 static void netdev_init_one_queue(struct net_device *dev, 5398 struct netdev_queue *queue, void *_unused) 5399 { 5400 /* Initialize queue lock */ 5401 spin_lock_init(&queue->_xmit_lock); 5402 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 5403 queue->xmit_lock_owner = -1; 5404 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 5405 queue->dev = dev; 5406 } 5407 5408 static int netif_alloc_netdev_queues(struct net_device *dev) 5409 { 5410 unsigned int count = dev->num_tx_queues; 5411 struct netdev_queue *tx; 5412 5413 BUG_ON(count < 1); 5414 5415 tx = kcalloc(count, sizeof(struct netdev_queue), GFP_KERNEL); 5416 if (!tx) { 5417 pr_err("netdev: Unable to allocate %u tx queues.\n", 5418 count); 5419 return -ENOMEM; 5420 } 5421 dev->_tx = tx; 5422 5423 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 5424 spin_lock_init(&dev->tx_global_lock); 5425 5426 return 0; 5427 } 5428 5429 /** 5430 * register_netdevice - register a network device 5431 * @dev: device to register 5432 * 5433 * Take a completed network device structure and add it to the kernel 5434 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 5435 * chain. 0 is returned on success. A negative errno code is returned 5436 * on a failure to set up the device, or if the name is a duplicate. 5437 * 5438 * Callers must hold the rtnl semaphore. You may want 5439 * register_netdev() instead of this. 5440 * 5441 * BUGS: 5442 * The locking appears insufficient to guarantee two parallel registers 5443 * will not get the same name. 5444 */ 5445 5446 int register_netdevice(struct net_device *dev) 5447 { 5448 int ret; 5449 struct net *net = dev_net(dev); 5450 5451 BUG_ON(dev_boot_phase); 5452 ASSERT_RTNL(); 5453 5454 might_sleep(); 5455 5456 /* When net_device's are persistent, this will be fatal. */ 5457 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 5458 BUG_ON(!net); 5459 5460 spin_lock_init(&dev->addr_list_lock); 5461 netdev_set_addr_lockdep_class(dev); 5462 5463 dev->iflink = -1; 5464 5465 ret = dev_get_valid_name(dev, dev->name); 5466 if (ret < 0) 5467 goto out; 5468 5469 /* Init, if this function is available */ 5470 if (dev->netdev_ops->ndo_init) { 5471 ret = dev->netdev_ops->ndo_init(dev); 5472 if (ret) { 5473 if (ret > 0) 5474 ret = -EIO; 5475 goto out; 5476 } 5477 } 5478 5479 dev->ifindex = dev_new_index(net); 5480 if (dev->iflink == -1) 5481 dev->iflink = dev->ifindex; 5482 5483 /* Transfer changeable features to wanted_features and enable 5484 * software offloads (GSO and GRO). 5485 */ 5486 dev->hw_features |= NETIF_F_SOFT_FEATURES; 5487 dev->features |= NETIF_F_SOFT_FEATURES; 5488 dev->wanted_features = dev->features & dev->hw_features; 5489 5490 /* Turn on no cache copy if HW is doing checksum */ 5491 dev->hw_features |= NETIF_F_NOCACHE_COPY; 5492 if ((dev->features & NETIF_F_ALL_CSUM) && 5493 !(dev->features & NETIF_F_NO_CSUM)) { 5494 dev->wanted_features |= NETIF_F_NOCACHE_COPY; 5495 dev->features |= NETIF_F_NOCACHE_COPY; 5496 } 5497 5498 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 5499 */ 5500 dev->vlan_features |= NETIF_F_HIGHDMA; 5501 5502 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 5503 ret = notifier_to_errno(ret); 5504 if (ret) 5505 goto err_uninit; 5506 5507 ret = netdev_register_kobject(dev); 5508 if (ret) 5509 goto err_uninit; 5510 dev->reg_state = NETREG_REGISTERED; 5511 5512 __netdev_update_features(dev); 5513 5514 /* 5515 * Default initial state at registry is that the 5516 * device is present. 5517 */ 5518 5519 set_bit(__LINK_STATE_PRESENT, &dev->state); 5520 5521 dev_init_scheduler(dev); 5522 dev_hold(dev); 5523 list_netdevice(dev); 5524 5525 /* Notify protocols, that a new device appeared. */ 5526 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 5527 ret = notifier_to_errno(ret); 5528 if (ret) { 5529 rollback_registered(dev); 5530 dev->reg_state = NETREG_UNREGISTERED; 5531 } 5532 /* 5533 * Prevent userspace races by waiting until the network 5534 * device is fully setup before sending notifications. 5535 */ 5536 if (!dev->rtnl_link_ops || 5537 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 5538 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 5539 5540 out: 5541 return ret; 5542 5543 err_uninit: 5544 if (dev->netdev_ops->ndo_uninit) 5545 dev->netdev_ops->ndo_uninit(dev); 5546 goto out; 5547 } 5548 EXPORT_SYMBOL(register_netdevice); 5549 5550 /** 5551 * init_dummy_netdev - init a dummy network device for NAPI 5552 * @dev: device to init 5553 * 5554 * This takes a network device structure and initialize the minimum 5555 * amount of fields so it can be used to schedule NAPI polls without 5556 * registering a full blown interface. This is to be used by drivers 5557 * that need to tie several hardware interfaces to a single NAPI 5558 * poll scheduler due to HW limitations. 5559 */ 5560 int init_dummy_netdev(struct net_device *dev) 5561 { 5562 /* Clear everything. Note we don't initialize spinlocks 5563 * are they aren't supposed to be taken by any of the 5564 * NAPI code and this dummy netdev is supposed to be 5565 * only ever used for NAPI polls 5566 */ 5567 memset(dev, 0, sizeof(struct net_device)); 5568 5569 /* make sure we BUG if trying to hit standard 5570 * register/unregister code path 5571 */ 5572 dev->reg_state = NETREG_DUMMY; 5573 5574 /* NAPI wants this */ 5575 INIT_LIST_HEAD(&dev->napi_list); 5576 5577 /* a dummy interface is started by default */ 5578 set_bit(__LINK_STATE_PRESENT, &dev->state); 5579 set_bit(__LINK_STATE_START, &dev->state); 5580 5581 /* Note : We dont allocate pcpu_refcnt for dummy devices, 5582 * because users of this 'device' dont need to change 5583 * its refcount. 5584 */ 5585 5586 return 0; 5587 } 5588 EXPORT_SYMBOL_GPL(init_dummy_netdev); 5589 5590 5591 /** 5592 * register_netdev - register a network device 5593 * @dev: device to register 5594 * 5595 * Take a completed network device structure and add it to the kernel 5596 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 5597 * chain. 0 is returned on success. A negative errno code is returned 5598 * on a failure to set up the device, or if the name is a duplicate. 5599 * 5600 * This is a wrapper around register_netdevice that takes the rtnl semaphore 5601 * and expands the device name if you passed a format string to 5602 * alloc_netdev. 5603 */ 5604 int register_netdev(struct net_device *dev) 5605 { 5606 int err; 5607 5608 rtnl_lock(); 5609 err = register_netdevice(dev); 5610 rtnl_unlock(); 5611 return err; 5612 } 5613 EXPORT_SYMBOL(register_netdev); 5614 5615 int netdev_refcnt_read(const struct net_device *dev) 5616 { 5617 int i, refcnt = 0; 5618 5619 for_each_possible_cpu(i) 5620 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 5621 return refcnt; 5622 } 5623 EXPORT_SYMBOL(netdev_refcnt_read); 5624 5625 /* 5626 * netdev_wait_allrefs - wait until all references are gone. 5627 * 5628 * This is called when unregistering network devices. 5629 * 5630 * Any protocol or device that holds a reference should register 5631 * for netdevice notification, and cleanup and put back the 5632 * reference if they receive an UNREGISTER event. 5633 * We can get stuck here if buggy protocols don't correctly 5634 * call dev_put. 5635 */ 5636 static void netdev_wait_allrefs(struct net_device *dev) 5637 { 5638 unsigned long rebroadcast_time, warning_time; 5639 int refcnt; 5640 5641 linkwatch_forget_dev(dev); 5642 5643 rebroadcast_time = warning_time = jiffies; 5644 refcnt = netdev_refcnt_read(dev); 5645 5646 while (refcnt != 0) { 5647 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 5648 rtnl_lock(); 5649 5650 /* Rebroadcast unregister notification */ 5651 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5652 /* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users 5653 * should have already handle it the first time */ 5654 5655 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 5656 &dev->state)) { 5657 /* We must not have linkwatch events 5658 * pending on unregister. If this 5659 * happens, we simply run the queue 5660 * unscheduled, resulting in a noop 5661 * for this device. 5662 */ 5663 linkwatch_run_queue(); 5664 } 5665 5666 __rtnl_unlock(); 5667 5668 rebroadcast_time = jiffies; 5669 } 5670 5671 msleep(250); 5672 5673 refcnt = netdev_refcnt_read(dev); 5674 5675 if (time_after(jiffies, warning_time + 10 * HZ)) { 5676 printk(KERN_EMERG "unregister_netdevice: " 5677 "waiting for %s to become free. Usage " 5678 "count = %d\n", 5679 dev->name, refcnt); 5680 warning_time = jiffies; 5681 } 5682 } 5683 } 5684 5685 /* The sequence is: 5686 * 5687 * rtnl_lock(); 5688 * ... 5689 * register_netdevice(x1); 5690 * register_netdevice(x2); 5691 * ... 5692 * unregister_netdevice(y1); 5693 * unregister_netdevice(y2); 5694 * ... 5695 * rtnl_unlock(); 5696 * free_netdev(y1); 5697 * free_netdev(y2); 5698 * 5699 * We are invoked by rtnl_unlock(). 5700 * This allows us to deal with problems: 5701 * 1) We can delete sysfs objects which invoke hotplug 5702 * without deadlocking with linkwatch via keventd. 5703 * 2) Since we run with the RTNL semaphore not held, we can sleep 5704 * safely in order to wait for the netdev refcnt to drop to zero. 5705 * 5706 * We must not return until all unregister events added during 5707 * the interval the lock was held have been completed. 5708 */ 5709 void netdev_run_todo(void) 5710 { 5711 struct list_head list; 5712 5713 /* Snapshot list, allow later requests */ 5714 list_replace_init(&net_todo_list, &list); 5715 5716 __rtnl_unlock(); 5717 5718 while (!list_empty(&list)) { 5719 struct net_device *dev 5720 = list_first_entry(&list, struct net_device, todo_list); 5721 list_del(&dev->todo_list); 5722 5723 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 5724 printk(KERN_ERR "network todo '%s' but state %d\n", 5725 dev->name, dev->reg_state); 5726 dump_stack(); 5727 continue; 5728 } 5729 5730 dev->reg_state = NETREG_UNREGISTERED; 5731 5732 on_each_cpu(flush_backlog, dev, 1); 5733 5734 netdev_wait_allrefs(dev); 5735 5736 /* paranoia */ 5737 BUG_ON(netdev_refcnt_read(dev)); 5738 WARN_ON(rcu_dereference_raw(dev->ip_ptr)); 5739 WARN_ON(rcu_dereference_raw(dev->ip6_ptr)); 5740 WARN_ON(dev->dn_ptr); 5741 5742 if (dev->destructor) 5743 dev->destructor(dev); 5744 5745 /* Free network device */ 5746 kobject_put(&dev->dev.kobj); 5747 } 5748 } 5749 5750 /* Convert net_device_stats to rtnl_link_stats64. They have the same 5751 * fields in the same order, with only the type differing. 5752 */ 5753 static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 5754 const struct net_device_stats *netdev_stats) 5755 { 5756 #if BITS_PER_LONG == 64 5757 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats)); 5758 memcpy(stats64, netdev_stats, sizeof(*stats64)); 5759 #else 5760 size_t i, n = sizeof(*stats64) / sizeof(u64); 5761 const unsigned long *src = (const unsigned long *)netdev_stats; 5762 u64 *dst = (u64 *)stats64; 5763 5764 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) != 5765 sizeof(*stats64) / sizeof(u64)); 5766 for (i = 0; i < n; i++) 5767 dst[i] = src[i]; 5768 #endif 5769 } 5770 5771 /** 5772 * dev_get_stats - get network device statistics 5773 * @dev: device to get statistics from 5774 * @storage: place to store stats 5775 * 5776 * Get network statistics from device. Return @storage. 5777 * The device driver may provide its own method by setting 5778 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 5779 * otherwise the internal statistics structure is used. 5780 */ 5781 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 5782 struct rtnl_link_stats64 *storage) 5783 { 5784 const struct net_device_ops *ops = dev->netdev_ops; 5785 5786 if (ops->ndo_get_stats64) { 5787 memset(storage, 0, sizeof(*storage)); 5788 ops->ndo_get_stats64(dev, storage); 5789 } else if (ops->ndo_get_stats) { 5790 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 5791 } else { 5792 netdev_stats_to_stats64(storage, &dev->stats); 5793 } 5794 storage->rx_dropped += atomic_long_read(&dev->rx_dropped); 5795 return storage; 5796 } 5797 EXPORT_SYMBOL(dev_get_stats); 5798 5799 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 5800 { 5801 struct netdev_queue *queue = dev_ingress_queue(dev); 5802 5803 #ifdef CONFIG_NET_CLS_ACT 5804 if (queue) 5805 return queue; 5806 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 5807 if (!queue) 5808 return NULL; 5809 netdev_init_one_queue(dev, queue, NULL); 5810 queue->qdisc = &noop_qdisc; 5811 queue->qdisc_sleeping = &noop_qdisc; 5812 rcu_assign_pointer(dev->ingress_queue, queue); 5813 #endif 5814 return queue; 5815 } 5816 5817 /** 5818 * alloc_netdev_mqs - allocate network device 5819 * @sizeof_priv: size of private data to allocate space for 5820 * @name: device name format string 5821 * @setup: callback to initialize device 5822 * @txqs: the number of TX subqueues to allocate 5823 * @rxqs: the number of RX subqueues to allocate 5824 * 5825 * Allocates a struct net_device with private data area for driver use 5826 * and performs basic initialization. Also allocates subquue structs 5827 * for each queue on the device. 5828 */ 5829 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 5830 void (*setup)(struct net_device *), 5831 unsigned int txqs, unsigned int rxqs) 5832 { 5833 struct net_device *dev; 5834 size_t alloc_size; 5835 struct net_device *p; 5836 5837 BUG_ON(strlen(name) >= sizeof(dev->name)); 5838 5839 if (txqs < 1) { 5840 pr_err("alloc_netdev: Unable to allocate device " 5841 "with zero queues.\n"); 5842 return NULL; 5843 } 5844 5845 #ifdef CONFIG_RPS 5846 if (rxqs < 1) { 5847 pr_err("alloc_netdev: Unable to allocate device " 5848 "with zero RX queues.\n"); 5849 return NULL; 5850 } 5851 #endif 5852 5853 alloc_size = sizeof(struct net_device); 5854 if (sizeof_priv) { 5855 /* ensure 32-byte alignment of private area */ 5856 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 5857 alloc_size += sizeof_priv; 5858 } 5859 /* ensure 32-byte alignment of whole construct */ 5860 alloc_size += NETDEV_ALIGN - 1; 5861 5862 p = kzalloc(alloc_size, GFP_KERNEL); 5863 if (!p) { 5864 printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n"); 5865 return NULL; 5866 } 5867 5868 dev = PTR_ALIGN(p, NETDEV_ALIGN); 5869 dev->padded = (char *)dev - (char *)p; 5870 5871 dev->pcpu_refcnt = alloc_percpu(int); 5872 if (!dev->pcpu_refcnt) 5873 goto free_p; 5874 5875 if (dev_addr_init(dev)) 5876 goto free_pcpu; 5877 5878 dev_mc_init(dev); 5879 dev_uc_init(dev); 5880 5881 dev_net_set(dev, &init_net); 5882 5883 dev->gso_max_size = GSO_MAX_SIZE; 5884 5885 INIT_LIST_HEAD(&dev->napi_list); 5886 INIT_LIST_HEAD(&dev->unreg_list); 5887 INIT_LIST_HEAD(&dev->link_watch_list); 5888 dev->priv_flags = IFF_XMIT_DST_RELEASE; 5889 setup(dev); 5890 5891 dev->num_tx_queues = txqs; 5892 dev->real_num_tx_queues = txqs; 5893 if (netif_alloc_netdev_queues(dev)) 5894 goto free_all; 5895 5896 #ifdef CONFIG_RPS 5897 dev->num_rx_queues = rxqs; 5898 dev->real_num_rx_queues = rxqs; 5899 if (netif_alloc_rx_queues(dev)) 5900 goto free_all; 5901 #endif 5902 5903 strcpy(dev->name, name); 5904 dev->group = INIT_NETDEV_GROUP; 5905 return dev; 5906 5907 free_all: 5908 free_netdev(dev); 5909 return NULL; 5910 5911 free_pcpu: 5912 free_percpu(dev->pcpu_refcnt); 5913 kfree(dev->_tx); 5914 #ifdef CONFIG_RPS 5915 kfree(dev->_rx); 5916 #endif 5917 5918 free_p: 5919 kfree(p); 5920 return NULL; 5921 } 5922 EXPORT_SYMBOL(alloc_netdev_mqs); 5923 5924 /** 5925 * free_netdev - free network device 5926 * @dev: device 5927 * 5928 * This function does the last stage of destroying an allocated device 5929 * interface. The reference to the device object is released. 5930 * If this is the last reference then it will be freed. 5931 */ 5932 void free_netdev(struct net_device *dev) 5933 { 5934 struct napi_struct *p, *n; 5935 5936 release_net(dev_net(dev)); 5937 5938 kfree(dev->_tx); 5939 #ifdef CONFIG_RPS 5940 kfree(dev->_rx); 5941 #endif 5942 5943 kfree(rcu_dereference_raw(dev->ingress_queue)); 5944 5945 /* Flush device addresses */ 5946 dev_addr_flush(dev); 5947 5948 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 5949 netif_napi_del(p); 5950 5951 free_percpu(dev->pcpu_refcnt); 5952 dev->pcpu_refcnt = NULL; 5953 5954 /* Compatibility with error handling in drivers */ 5955 if (dev->reg_state == NETREG_UNINITIALIZED) { 5956 kfree((char *)dev - dev->padded); 5957 return; 5958 } 5959 5960 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 5961 dev->reg_state = NETREG_RELEASED; 5962 5963 /* will free via device release */ 5964 put_device(&dev->dev); 5965 } 5966 EXPORT_SYMBOL(free_netdev); 5967 5968 /** 5969 * synchronize_net - Synchronize with packet receive processing 5970 * 5971 * Wait for packets currently being received to be done. 5972 * Does not block later packets from starting. 5973 */ 5974 void synchronize_net(void) 5975 { 5976 might_sleep(); 5977 if (rtnl_is_locked()) 5978 synchronize_rcu_expedited(); 5979 else 5980 synchronize_rcu(); 5981 } 5982 EXPORT_SYMBOL(synchronize_net); 5983 5984 /** 5985 * unregister_netdevice_queue - remove device from the kernel 5986 * @dev: device 5987 * @head: list 5988 * 5989 * This function shuts down a device interface and removes it 5990 * from the kernel tables. 5991 * If head not NULL, device is queued to be unregistered later. 5992 * 5993 * Callers must hold the rtnl semaphore. You may want 5994 * unregister_netdev() instead of this. 5995 */ 5996 5997 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 5998 { 5999 ASSERT_RTNL(); 6000 6001 if (head) { 6002 list_move_tail(&dev->unreg_list, head); 6003 } else { 6004 rollback_registered(dev); 6005 /* Finish processing unregister after unlock */ 6006 net_set_todo(dev); 6007 } 6008 } 6009 EXPORT_SYMBOL(unregister_netdevice_queue); 6010 6011 /** 6012 * unregister_netdevice_many - unregister many devices 6013 * @head: list of devices 6014 */ 6015 void unregister_netdevice_many(struct list_head *head) 6016 { 6017 struct net_device *dev; 6018 6019 if (!list_empty(head)) { 6020 rollback_registered_many(head); 6021 list_for_each_entry(dev, head, unreg_list) 6022 net_set_todo(dev); 6023 } 6024 } 6025 EXPORT_SYMBOL(unregister_netdevice_many); 6026 6027 /** 6028 * unregister_netdev - remove device from the kernel 6029 * @dev: device 6030 * 6031 * This function shuts down a device interface and removes it 6032 * from the kernel tables. 6033 * 6034 * This is just a wrapper for unregister_netdevice that takes 6035 * the rtnl semaphore. In general you want to use this and not 6036 * unregister_netdevice. 6037 */ 6038 void unregister_netdev(struct net_device *dev) 6039 { 6040 rtnl_lock(); 6041 unregister_netdevice(dev); 6042 rtnl_unlock(); 6043 } 6044 EXPORT_SYMBOL(unregister_netdev); 6045 6046 /** 6047 * dev_change_net_namespace - move device to different nethost namespace 6048 * @dev: device 6049 * @net: network namespace 6050 * @pat: If not NULL name pattern to try if the current device name 6051 * is already taken in the destination network namespace. 6052 * 6053 * This function shuts down a device interface and moves it 6054 * to a new network namespace. On success 0 is returned, on 6055 * a failure a netagive errno code is returned. 6056 * 6057 * Callers must hold the rtnl semaphore. 6058 */ 6059 6060 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat) 6061 { 6062 int err; 6063 6064 ASSERT_RTNL(); 6065 6066 /* Don't allow namespace local devices to be moved. */ 6067 err = -EINVAL; 6068 if (dev->features & NETIF_F_NETNS_LOCAL) 6069 goto out; 6070 6071 /* Ensure the device has been registrered */ 6072 err = -EINVAL; 6073 if (dev->reg_state != NETREG_REGISTERED) 6074 goto out; 6075 6076 /* Get out if there is nothing todo */ 6077 err = 0; 6078 if (net_eq(dev_net(dev), net)) 6079 goto out; 6080 6081 /* Pick the destination device name, and ensure 6082 * we can use it in the destination network namespace. 6083 */ 6084 err = -EEXIST; 6085 if (__dev_get_by_name(net, dev->name)) { 6086 /* We get here if we can't use the current device name */ 6087 if (!pat) 6088 goto out; 6089 if (dev_get_valid_name(dev, pat) < 0) 6090 goto out; 6091 } 6092 6093 /* 6094 * And now a mini version of register_netdevice unregister_netdevice. 6095 */ 6096 6097 /* If device is running close it first. */ 6098 dev_close(dev); 6099 6100 /* And unlink it from device chain */ 6101 err = -ENODEV; 6102 unlist_netdevice(dev); 6103 6104 synchronize_net(); 6105 6106 /* Shutdown queueing discipline. */ 6107 dev_shutdown(dev); 6108 6109 /* Notify protocols, that we are about to destroy 6110 this device. They should clean all the things. 6111 6112 Note that dev->reg_state stays at NETREG_REGISTERED. 6113 This is wanted because this way 8021q and macvlan know 6114 the device is just moving and can keep their slaves up. 6115 */ 6116 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 6117 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 6118 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U); 6119 6120 /* 6121 * Flush the unicast and multicast chains 6122 */ 6123 dev_uc_flush(dev); 6124 dev_mc_flush(dev); 6125 6126 /* Actually switch the network namespace */ 6127 dev_net_set(dev, net); 6128 6129 /* If there is an ifindex conflict assign a new one */ 6130 if (__dev_get_by_index(net, dev->ifindex)) { 6131 int iflink = (dev->iflink == dev->ifindex); 6132 dev->ifindex = dev_new_index(net); 6133 if (iflink) 6134 dev->iflink = dev->ifindex; 6135 } 6136 6137 /* Fixup kobjects */ 6138 err = device_rename(&dev->dev, dev->name); 6139 WARN_ON(err); 6140 6141 /* Add the device back in the hashes */ 6142 list_netdevice(dev); 6143 6144 /* Notify protocols, that a new device appeared. */ 6145 call_netdevice_notifiers(NETDEV_REGISTER, dev); 6146 6147 /* 6148 * Prevent userspace races by waiting until the network 6149 * device is fully setup before sending notifications. 6150 */ 6151 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 6152 6153 synchronize_net(); 6154 err = 0; 6155 out: 6156 return err; 6157 } 6158 EXPORT_SYMBOL_GPL(dev_change_net_namespace); 6159 6160 static int dev_cpu_callback(struct notifier_block *nfb, 6161 unsigned long action, 6162 void *ocpu) 6163 { 6164 struct sk_buff **list_skb; 6165 struct sk_buff *skb; 6166 unsigned int cpu, oldcpu = (unsigned long)ocpu; 6167 struct softnet_data *sd, *oldsd; 6168 6169 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) 6170 return NOTIFY_OK; 6171 6172 local_irq_disable(); 6173 cpu = smp_processor_id(); 6174 sd = &per_cpu(softnet_data, cpu); 6175 oldsd = &per_cpu(softnet_data, oldcpu); 6176 6177 /* Find end of our completion_queue. */ 6178 list_skb = &sd->completion_queue; 6179 while (*list_skb) 6180 list_skb = &(*list_skb)->next; 6181 /* Append completion queue from offline CPU. */ 6182 *list_skb = oldsd->completion_queue; 6183 oldsd->completion_queue = NULL; 6184 6185 /* Append output queue from offline CPU. */ 6186 if (oldsd->output_queue) { 6187 *sd->output_queue_tailp = oldsd->output_queue; 6188 sd->output_queue_tailp = oldsd->output_queue_tailp; 6189 oldsd->output_queue = NULL; 6190 oldsd->output_queue_tailp = &oldsd->output_queue; 6191 } 6192 /* Append NAPI poll list from offline CPU. */ 6193 if (!list_empty(&oldsd->poll_list)) { 6194 list_splice_init(&oldsd->poll_list, &sd->poll_list); 6195 raise_softirq_irqoff(NET_RX_SOFTIRQ); 6196 } 6197 6198 raise_softirq_irqoff(NET_TX_SOFTIRQ); 6199 local_irq_enable(); 6200 6201 /* Process offline CPU's input_pkt_queue */ 6202 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 6203 netif_rx(skb); 6204 input_queue_head_incr(oldsd); 6205 } 6206 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) { 6207 netif_rx(skb); 6208 input_queue_head_incr(oldsd); 6209 } 6210 6211 return NOTIFY_OK; 6212 } 6213 6214 6215 /** 6216 * netdev_increment_features - increment feature set by one 6217 * @all: current feature set 6218 * @one: new feature set 6219 * @mask: mask feature set 6220 * 6221 * Computes a new feature set after adding a device with feature set 6222 * @one to the master device with current feature set @all. Will not 6223 * enable anything that is off in @mask. Returns the new feature set. 6224 */ 6225 u32 netdev_increment_features(u32 all, u32 one, u32 mask) 6226 { 6227 if (mask & NETIF_F_GEN_CSUM) 6228 mask |= NETIF_F_ALL_CSUM; 6229 mask |= NETIF_F_VLAN_CHALLENGED; 6230 6231 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask; 6232 all &= one | ~NETIF_F_ALL_FOR_ALL; 6233 6234 /* If device needs checksumming, downgrade to it. */ 6235 if (all & (NETIF_F_ALL_CSUM & ~NETIF_F_NO_CSUM)) 6236 all &= ~NETIF_F_NO_CSUM; 6237 6238 /* If one device supports hw checksumming, set for all. */ 6239 if (all & NETIF_F_GEN_CSUM) 6240 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); 6241 6242 return all; 6243 } 6244 EXPORT_SYMBOL(netdev_increment_features); 6245 6246 static struct hlist_head *netdev_create_hash(void) 6247 { 6248 int i; 6249 struct hlist_head *hash; 6250 6251 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL); 6252 if (hash != NULL) 6253 for (i = 0; i < NETDEV_HASHENTRIES; i++) 6254 INIT_HLIST_HEAD(&hash[i]); 6255 6256 return hash; 6257 } 6258 6259 /* Initialize per network namespace state */ 6260 static int __net_init netdev_init(struct net *net) 6261 { 6262 INIT_LIST_HEAD(&net->dev_base_head); 6263 6264 net->dev_name_head = netdev_create_hash(); 6265 if (net->dev_name_head == NULL) 6266 goto err_name; 6267 6268 net->dev_index_head = netdev_create_hash(); 6269 if (net->dev_index_head == NULL) 6270 goto err_idx; 6271 6272 return 0; 6273 6274 err_idx: 6275 kfree(net->dev_name_head); 6276 err_name: 6277 return -ENOMEM; 6278 } 6279 6280 /** 6281 * netdev_drivername - network driver for the device 6282 * @dev: network device 6283 * 6284 * Determine network driver for device. 6285 */ 6286 const char *netdev_drivername(const struct net_device *dev) 6287 { 6288 const struct device_driver *driver; 6289 const struct device *parent; 6290 const char *empty = ""; 6291 6292 parent = dev->dev.parent; 6293 if (!parent) 6294 return empty; 6295 6296 driver = parent->driver; 6297 if (driver && driver->name) 6298 return driver->name; 6299 return empty; 6300 } 6301 6302 static int __netdev_printk(const char *level, const struct net_device *dev, 6303 struct va_format *vaf) 6304 { 6305 int r; 6306 6307 if (dev && dev->dev.parent) 6308 r = dev_printk(level, dev->dev.parent, "%s: %pV", 6309 netdev_name(dev), vaf); 6310 else if (dev) 6311 r = printk("%s%s: %pV", level, netdev_name(dev), vaf); 6312 else 6313 r = printk("%s(NULL net_device): %pV", level, vaf); 6314 6315 return r; 6316 } 6317 6318 int netdev_printk(const char *level, const struct net_device *dev, 6319 const char *format, ...) 6320 { 6321 struct va_format vaf; 6322 va_list args; 6323 int r; 6324 6325 va_start(args, format); 6326 6327 vaf.fmt = format; 6328 vaf.va = &args; 6329 6330 r = __netdev_printk(level, dev, &vaf); 6331 va_end(args); 6332 6333 return r; 6334 } 6335 EXPORT_SYMBOL(netdev_printk); 6336 6337 #define define_netdev_printk_level(func, level) \ 6338 int func(const struct net_device *dev, const char *fmt, ...) \ 6339 { \ 6340 int r; \ 6341 struct va_format vaf; \ 6342 va_list args; \ 6343 \ 6344 va_start(args, fmt); \ 6345 \ 6346 vaf.fmt = fmt; \ 6347 vaf.va = &args; \ 6348 \ 6349 r = __netdev_printk(level, dev, &vaf); \ 6350 va_end(args); \ 6351 \ 6352 return r; \ 6353 } \ 6354 EXPORT_SYMBOL(func); 6355 6356 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 6357 define_netdev_printk_level(netdev_alert, KERN_ALERT); 6358 define_netdev_printk_level(netdev_crit, KERN_CRIT); 6359 define_netdev_printk_level(netdev_err, KERN_ERR); 6360 define_netdev_printk_level(netdev_warn, KERN_WARNING); 6361 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 6362 define_netdev_printk_level(netdev_info, KERN_INFO); 6363 6364 static void __net_exit netdev_exit(struct net *net) 6365 { 6366 kfree(net->dev_name_head); 6367 kfree(net->dev_index_head); 6368 } 6369 6370 static struct pernet_operations __net_initdata netdev_net_ops = { 6371 .init = netdev_init, 6372 .exit = netdev_exit, 6373 }; 6374 6375 static void __net_exit default_device_exit(struct net *net) 6376 { 6377 struct net_device *dev, *aux; 6378 /* 6379 * Push all migratable network devices back to the 6380 * initial network namespace 6381 */ 6382 rtnl_lock(); 6383 for_each_netdev_safe(net, dev, aux) { 6384 int err; 6385 char fb_name[IFNAMSIZ]; 6386 6387 /* Ignore unmoveable devices (i.e. loopback) */ 6388 if (dev->features & NETIF_F_NETNS_LOCAL) 6389 continue; 6390 6391 /* Leave virtual devices for the generic cleanup */ 6392 if (dev->rtnl_link_ops) 6393 continue; 6394 6395 /* Push remaining network devices to init_net */ 6396 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 6397 err = dev_change_net_namespace(dev, &init_net, fb_name); 6398 if (err) { 6399 printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n", 6400 __func__, dev->name, err); 6401 BUG(); 6402 } 6403 } 6404 rtnl_unlock(); 6405 } 6406 6407 static void __net_exit default_device_exit_batch(struct list_head *net_list) 6408 { 6409 /* At exit all network devices most be removed from a network 6410 * namespace. Do this in the reverse order of registration. 6411 * Do this across as many network namespaces as possible to 6412 * improve batching efficiency. 6413 */ 6414 struct net_device *dev; 6415 struct net *net; 6416 LIST_HEAD(dev_kill_list); 6417 6418 rtnl_lock(); 6419 list_for_each_entry(net, net_list, exit_list) { 6420 for_each_netdev_reverse(net, dev) { 6421 if (dev->rtnl_link_ops) 6422 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 6423 else 6424 unregister_netdevice_queue(dev, &dev_kill_list); 6425 } 6426 } 6427 unregister_netdevice_many(&dev_kill_list); 6428 list_del(&dev_kill_list); 6429 rtnl_unlock(); 6430 } 6431 6432 static struct pernet_operations __net_initdata default_device_ops = { 6433 .exit = default_device_exit, 6434 .exit_batch = default_device_exit_batch, 6435 }; 6436 6437 /* 6438 * Initialize the DEV module. At boot time this walks the device list and 6439 * unhooks any devices that fail to initialise (normally hardware not 6440 * present) and leaves us with a valid list of present and active devices. 6441 * 6442 */ 6443 6444 /* 6445 * This is called single threaded during boot, so no need 6446 * to take the rtnl semaphore. 6447 */ 6448 static int __init net_dev_init(void) 6449 { 6450 int i, rc = -ENOMEM; 6451 6452 BUG_ON(!dev_boot_phase); 6453 6454 if (dev_proc_init()) 6455 goto out; 6456 6457 if (netdev_kobject_init()) 6458 goto out; 6459 6460 INIT_LIST_HEAD(&ptype_all); 6461 for (i = 0; i < PTYPE_HASH_SIZE; i++) 6462 INIT_LIST_HEAD(&ptype_base[i]); 6463 6464 if (register_pernet_subsys(&netdev_net_ops)) 6465 goto out; 6466 6467 /* 6468 * Initialise the packet receive queues. 6469 */ 6470 6471 for_each_possible_cpu(i) { 6472 struct softnet_data *sd = &per_cpu(softnet_data, i); 6473 6474 memset(sd, 0, sizeof(*sd)); 6475 skb_queue_head_init(&sd->input_pkt_queue); 6476 skb_queue_head_init(&sd->process_queue); 6477 sd->completion_queue = NULL; 6478 INIT_LIST_HEAD(&sd->poll_list); 6479 sd->output_queue = NULL; 6480 sd->output_queue_tailp = &sd->output_queue; 6481 #ifdef CONFIG_RPS 6482 sd->csd.func = rps_trigger_softirq; 6483 sd->csd.info = sd; 6484 sd->csd.flags = 0; 6485 sd->cpu = i; 6486 #endif 6487 6488 sd->backlog.poll = process_backlog; 6489 sd->backlog.weight = weight_p; 6490 sd->backlog.gro_list = NULL; 6491 sd->backlog.gro_count = 0; 6492 } 6493 6494 dev_boot_phase = 0; 6495 6496 /* The loopback device is special if any other network devices 6497 * is present in a network namespace the loopback device must 6498 * be present. Since we now dynamically allocate and free the 6499 * loopback device ensure this invariant is maintained by 6500 * keeping the loopback device as the first device on the 6501 * list of network devices. Ensuring the loopback devices 6502 * is the first device that appears and the last network device 6503 * that disappears. 6504 */ 6505 if (register_pernet_device(&loopback_net_ops)) 6506 goto out; 6507 6508 if (register_pernet_device(&default_device_ops)) 6509 goto out; 6510 6511 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 6512 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 6513 6514 hotcpu_notifier(dev_cpu_callback, 0); 6515 dst_init(); 6516 dev_mcast_init(); 6517 rc = 0; 6518 out: 6519 return rc; 6520 } 6521 6522 subsys_initcall(net_dev_init); 6523 6524 static int __init initialize_hashrnd(void) 6525 { 6526 get_random_bytes(&hashrnd, sizeof(hashrnd)); 6527 return 0; 6528 } 6529 6530 late_initcall_sync(initialize_hashrnd); 6531 6532