| 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 <linux/bitops.h> |
| 77 | #include <linux/capability.h> |
| 78 | #include <linux/cpu.h> |
| 79 | #include <linux/types.h> |
| 80 | #include <linux/kernel.h> |
| 81 | #include <linux/hash.h> |
| 82 | #include <linux/slab.h> |
| 83 | #include <linux/sched.h> |
| 84 | #include <linux/mutex.h> |
| 85 | #include <linux/string.h> |
| 86 | #include <linux/mm.h> |
| 87 | #include <linux/socket.h> |
| 88 | #include <linux/sockios.h> |
| 89 | #include <linux/errno.h> |
| 90 | #include <linux/interrupt.h> |
| 91 | #include <linux/if_ether.h> |
| 92 | #include <linux/netdevice.h> |
| 93 | #include <linux/etherdevice.h> |
| 94 | #include <linux/ethtool.h> |
| 95 | #include <linux/notifier.h> |
| 96 | #include <linux/skbuff.h> |
| 97 | #include <net/net_namespace.h> |
| 98 | #include <net/sock.h> |
| 99 | #include <linux/rtnetlink.h> |
| 100 | #include <linux/stat.h> |
| 101 | #include <net/dst.h> |
| 102 | #include <net/pkt_sched.h> |
| 103 | #include <net/checksum.h> |
| 104 | #include <net/xfrm.h> |
| 105 | #include <linux/highmem.h> |
| 106 | #include <linux/init.h> |
| 107 | #include <linux/module.h> |
| 108 | #include <linux/netpoll.h> |
| 109 | #include <linux/rcupdate.h> |
| 110 | #include <linux/delay.h> |
| 111 | #include <net/iw_handler.h> |
| 112 | #include <asm/current.h> |
| 113 | #include <linux/audit.h> |
| 114 | #include <linux/dmaengine.h> |
| 115 | #include <linux/err.h> |
| 116 | #include <linux/ctype.h> |
| 117 | #include <linux/if_arp.h> |
| 118 | #include <linux/if_vlan.h> |
| 119 | #include <linux/ip.h> |
| 120 | #include <net/ip.h> |
| 121 | #include <linux/ipv6.h> |
| 122 | #include <linux/in.h> |
| 123 | #include <linux/jhash.h> |
| 124 | #include <linux/random.h> |
| 125 | #include <trace/events/napi.h> |
| 126 | #include <trace/events/net.h> |
| 127 | #include <trace/events/skb.h> |
| 128 | #include <linux/pci.h> |
| 129 | #include <linux/inetdevice.h> |
| 130 | #include <linux/cpu_rmap.h> |
| 131 | #include <linux/static_key.h> |
| 132 | #include <linux/hashtable.h> |
| 133 | #include <linux/vmalloc.h> |
| 134 | #include <linux/if_macvlan.h> |
| 135 | |
| 136 | #include "net-sysfs.h" |
| 137 | |
| 138 | /* Instead of increasing this, you should create a hash table. */ |
| 139 | #define MAX_GRO_SKBS 8 |
| 140 | |
| 141 | /* This should be increased if a protocol with a bigger head is added. */ |
| 142 | #define GRO_MAX_HEAD (MAX_HEADER + 128) |
| 143 | |
| 144 | static DEFINE_SPINLOCK(ptype_lock); |
| 145 | static DEFINE_SPINLOCK(offload_lock); |
| 146 | struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; |
| 147 | struct list_head ptype_all __read_mostly; /* Taps */ |
| 148 | static struct list_head offload_base __read_mostly; |
| 149 | |
| 150 | /* |
| 151 | * The @dev_base_head list is protected by @dev_base_lock and the rtnl |
| 152 | * semaphore. |
| 153 | * |
| 154 | * Pure readers hold dev_base_lock for reading, or rcu_read_lock() |
| 155 | * |
| 156 | * Writers must hold the rtnl semaphore while they loop through the |
| 157 | * dev_base_head list, and hold dev_base_lock for writing when they do the |
| 158 | * actual updates. This allows pure readers to access the list even |
| 159 | * while a writer is preparing to update it. |
| 160 | * |
| 161 | * To put it another way, dev_base_lock is held for writing only to |
| 162 | * protect against pure readers; the rtnl semaphore provides the |
| 163 | * protection against other writers. |
| 164 | * |
| 165 | * See, for example usages, register_netdevice() and |
| 166 | * unregister_netdevice(), which must be called with the rtnl |
| 167 | * semaphore held. |
| 168 | */ |
| 169 | DEFINE_RWLOCK(dev_base_lock); |
| 170 | EXPORT_SYMBOL(dev_base_lock); |
| 171 | |
| 172 | /* protects napi_hash addition/deletion and napi_gen_id */ |
| 173 | static DEFINE_SPINLOCK(napi_hash_lock); |
| 174 | |
| 175 | static unsigned int napi_gen_id; |
| 176 | static DEFINE_HASHTABLE(napi_hash, 8); |
| 177 | |
| 178 | static seqcount_t devnet_rename_seq; |
| 179 | |
| 180 | static inline void dev_base_seq_inc(struct net *net) |
| 181 | { |
| 182 | while (++net->dev_base_seq == 0); |
| 183 | } |
| 184 | |
| 185 | static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) |
| 186 | { |
| 187 | unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ)); |
| 188 | |
| 189 | return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; |
| 190 | } |
| 191 | |
| 192 | static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) |
| 193 | { |
| 194 | return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; |
| 195 | } |
| 196 | |
| 197 | static inline void rps_lock(struct softnet_data *sd) |
| 198 | { |
| 199 | #ifdef CONFIG_RPS |
| 200 | spin_lock(&sd->input_pkt_queue.lock); |
| 201 | #endif |
| 202 | } |
| 203 | |
| 204 | static inline void rps_unlock(struct softnet_data *sd) |
| 205 | { |
| 206 | #ifdef CONFIG_RPS |
| 207 | spin_unlock(&sd->input_pkt_queue.lock); |
| 208 | #endif |
| 209 | } |
| 210 | |
| 211 | /* Device list insertion */ |
| 212 | static void list_netdevice(struct net_device *dev) |
| 213 | { |
| 214 | struct net *net = dev_net(dev); |
| 215 | |
| 216 | ASSERT_RTNL(); |
| 217 | |
| 218 | write_lock_bh(&dev_base_lock); |
| 219 | list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); |
| 220 | hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); |
| 221 | hlist_add_head_rcu(&dev->index_hlist, |
| 222 | dev_index_hash(net, dev->ifindex)); |
| 223 | write_unlock_bh(&dev_base_lock); |
| 224 | |
| 225 | dev_base_seq_inc(net); |
| 226 | } |
| 227 | |
| 228 | /* Device list removal |
| 229 | * caller must respect a RCU grace period before freeing/reusing dev |
| 230 | */ |
| 231 | static void unlist_netdevice(struct net_device *dev) |
| 232 | { |
| 233 | ASSERT_RTNL(); |
| 234 | |
| 235 | /* Unlink dev from the device chain */ |
| 236 | write_lock_bh(&dev_base_lock); |
| 237 | list_del_rcu(&dev->dev_list); |
| 238 | hlist_del_rcu(&dev->name_hlist); |
| 239 | hlist_del_rcu(&dev->index_hlist); |
| 240 | write_unlock_bh(&dev_base_lock); |
| 241 | |
| 242 | dev_base_seq_inc(dev_net(dev)); |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Our notifier list |
| 247 | */ |
| 248 | |
| 249 | static RAW_NOTIFIER_HEAD(netdev_chain); |
| 250 | |
| 251 | /* |
| 252 | * Device drivers call our routines to queue packets here. We empty the |
| 253 | * queue in the local softnet handler. |
| 254 | */ |
| 255 | |
| 256 | DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); |
| 257 | EXPORT_PER_CPU_SYMBOL(softnet_data); |
| 258 | |
| 259 | #ifdef CONFIG_LOCKDEP |
| 260 | /* |
| 261 | * register_netdevice() inits txq->_xmit_lock and sets lockdep class |
| 262 | * according to dev->type |
| 263 | */ |
| 264 | static const unsigned short netdev_lock_type[] = |
| 265 | {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, |
| 266 | ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, |
| 267 | ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, |
| 268 | ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, |
| 269 | ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, |
| 270 | ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, |
| 271 | ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, |
| 272 | ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, |
| 273 | ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, |
| 274 | ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, |
| 275 | ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, |
| 276 | ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, |
| 277 | ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, |
| 278 | ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, |
| 279 | ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; |
| 280 | |
| 281 | static const char *const netdev_lock_name[] = |
| 282 | {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", |
| 283 | "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", |
| 284 | "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", |
| 285 | "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", |
| 286 | "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", |
| 287 | "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", |
| 288 | "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", |
| 289 | "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", |
| 290 | "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", |
| 291 | "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", |
| 292 | "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", |
| 293 | "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", |
| 294 | "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", |
| 295 | "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", |
| 296 | "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; |
| 297 | |
| 298 | static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; |
| 299 | static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; |
| 300 | |
| 301 | static inline unsigned short netdev_lock_pos(unsigned short dev_type) |
| 302 | { |
| 303 | int i; |
| 304 | |
| 305 | for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) |
| 306 | if (netdev_lock_type[i] == dev_type) |
| 307 | return i; |
| 308 | /* the last key is used by default */ |
| 309 | return ARRAY_SIZE(netdev_lock_type) - 1; |
| 310 | } |
| 311 | |
| 312 | static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, |
| 313 | unsigned short dev_type) |
| 314 | { |
| 315 | int i; |
| 316 | |
| 317 | i = netdev_lock_pos(dev_type); |
| 318 | lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], |
| 319 | netdev_lock_name[i]); |
| 320 | } |
| 321 | |
| 322 | static inline void netdev_set_addr_lockdep_class(struct net_device *dev) |
| 323 | { |
| 324 | int i; |
| 325 | |
| 326 | i = netdev_lock_pos(dev->type); |
| 327 | lockdep_set_class_and_name(&dev->addr_list_lock, |
| 328 | &netdev_addr_lock_key[i], |
| 329 | netdev_lock_name[i]); |
| 330 | } |
| 331 | #else |
| 332 | static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, |
| 333 | unsigned short dev_type) |
| 334 | { |
| 335 | } |
| 336 | static inline void netdev_set_addr_lockdep_class(struct net_device *dev) |
| 337 | { |
| 338 | } |
| 339 | #endif |
| 340 | |
| 341 | /******************************************************************************* |
| 342 | |
| 343 | Protocol management and registration routines |
| 344 | |
| 345 | *******************************************************************************/ |
| 346 | |
| 347 | /* |
| 348 | * Add a protocol ID to the list. Now that the input handler is |
| 349 | * smarter we can dispense with all the messy stuff that used to be |
| 350 | * here. |
| 351 | * |
| 352 | * BEWARE!!! Protocol handlers, mangling input packets, |
| 353 | * MUST BE last in hash buckets and checking protocol handlers |
| 354 | * MUST start from promiscuous ptype_all chain in net_bh. |
| 355 | * It is true now, do not change it. |
| 356 | * Explanation follows: if protocol handler, mangling packet, will |
| 357 | * be the first on list, it is not able to sense, that packet |
| 358 | * is cloned and should be copied-on-write, so that it will |
| 359 | * change it and subsequent readers will get broken packet. |
| 360 | * --ANK (980803) |
| 361 | */ |
| 362 | |
| 363 | static inline struct list_head *ptype_head(const struct packet_type *pt) |
| 364 | { |
| 365 | if (pt->type == htons(ETH_P_ALL)) |
| 366 | return &ptype_all; |
| 367 | else |
| 368 | return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; |
| 369 | } |
| 370 | |
| 371 | /** |
| 372 | * dev_add_pack - add packet handler |
| 373 | * @pt: packet type declaration |
| 374 | * |
| 375 | * Add a protocol handler to the networking stack. The passed &packet_type |
| 376 | * is linked into kernel lists and may not be freed until it has been |
| 377 | * removed from the kernel lists. |
| 378 | * |
| 379 | * This call does not sleep therefore it can not |
| 380 | * guarantee all CPU's that are in middle of receiving packets |
| 381 | * will see the new packet type (until the next received packet). |
| 382 | */ |
| 383 | |
| 384 | void dev_add_pack(struct packet_type *pt) |
| 385 | { |
| 386 | struct list_head *head = ptype_head(pt); |
| 387 | |
| 388 | spin_lock(&ptype_lock); |
| 389 | list_add_rcu(&pt->list, head); |
| 390 | spin_unlock(&ptype_lock); |
| 391 | } |
| 392 | EXPORT_SYMBOL(dev_add_pack); |
| 393 | |
| 394 | /** |
| 395 | * __dev_remove_pack - remove packet handler |
| 396 | * @pt: packet type declaration |
| 397 | * |
| 398 | * Remove a protocol handler that was previously added to the kernel |
| 399 | * protocol handlers by dev_add_pack(). The passed &packet_type is removed |
| 400 | * from the kernel lists and can be freed or reused once this function |
| 401 | * returns. |
| 402 | * |
| 403 | * The packet type might still be in use by receivers |
| 404 | * and must not be freed until after all the CPU's have gone |
| 405 | * through a quiescent state. |
| 406 | */ |
| 407 | void __dev_remove_pack(struct packet_type *pt) |
| 408 | { |
| 409 | struct list_head *head = ptype_head(pt); |
| 410 | struct packet_type *pt1; |
| 411 | |
| 412 | spin_lock(&ptype_lock); |
| 413 | |
| 414 | list_for_each_entry(pt1, head, list) { |
| 415 | if (pt == pt1) { |
| 416 | list_del_rcu(&pt->list); |
| 417 | goto out; |
| 418 | } |
| 419 | } |
| 420 | |
| 421 | pr_warn("dev_remove_pack: %p not found\n", pt); |
| 422 | out: |
| 423 | spin_unlock(&ptype_lock); |
| 424 | } |
| 425 | EXPORT_SYMBOL(__dev_remove_pack); |
| 426 | |
| 427 | /** |
| 428 | * dev_remove_pack - remove packet handler |
| 429 | * @pt: packet type declaration |
| 430 | * |
| 431 | * Remove a protocol handler that was previously added to the kernel |
| 432 | * protocol handlers by dev_add_pack(). The passed &packet_type is removed |
| 433 | * from the kernel lists and can be freed or reused once this function |
| 434 | * returns. |
| 435 | * |
| 436 | * This call sleeps to guarantee that no CPU is looking at the packet |
| 437 | * type after return. |
| 438 | */ |
| 439 | void dev_remove_pack(struct packet_type *pt) |
| 440 | { |
| 441 | __dev_remove_pack(pt); |
| 442 | |
| 443 | synchronize_net(); |
| 444 | } |
| 445 | EXPORT_SYMBOL(dev_remove_pack); |
| 446 | |
| 447 | |
| 448 | /** |
| 449 | * dev_add_offload - register offload handlers |
| 450 | * @po: protocol offload declaration |
| 451 | * |
| 452 | * Add protocol offload handlers to the networking stack. The passed |
| 453 | * &proto_offload is linked into kernel lists and may not be freed until |
| 454 | * it has been removed from the kernel lists. |
| 455 | * |
| 456 | * This call does not sleep therefore it can not |
| 457 | * guarantee all CPU's that are in middle of receiving packets |
| 458 | * will see the new offload handlers (until the next received packet). |
| 459 | */ |
| 460 | void dev_add_offload(struct packet_offload *po) |
| 461 | { |
| 462 | struct list_head *head = &offload_base; |
| 463 | |
| 464 | spin_lock(&offload_lock); |
| 465 | list_add_rcu(&po->list, head); |
| 466 | spin_unlock(&offload_lock); |
| 467 | } |
| 468 | EXPORT_SYMBOL(dev_add_offload); |
| 469 | |
| 470 | /** |
| 471 | * __dev_remove_offload - remove offload handler |
| 472 | * @po: packet offload declaration |
| 473 | * |
| 474 | * Remove a protocol offload handler that was previously added to the |
| 475 | * kernel offload handlers by dev_add_offload(). The passed &offload_type |
| 476 | * is removed from the kernel lists and can be freed or reused once this |
| 477 | * function returns. |
| 478 | * |
| 479 | * The packet type might still be in use by receivers |
| 480 | * and must not be freed until after all the CPU's have gone |
| 481 | * through a quiescent state. |
| 482 | */ |
| 483 | static void __dev_remove_offload(struct packet_offload *po) |
| 484 | { |
| 485 | struct list_head *head = &offload_base; |
| 486 | struct packet_offload *po1; |
| 487 | |
| 488 | spin_lock(&offload_lock); |
| 489 | |
| 490 | list_for_each_entry(po1, head, list) { |
| 491 | if (po == po1) { |
| 492 | list_del_rcu(&po->list); |
| 493 | goto out; |
| 494 | } |
| 495 | } |
| 496 | |
| 497 | pr_warn("dev_remove_offload: %p not found\n", po); |
| 498 | out: |
| 499 | spin_unlock(&offload_lock); |
| 500 | } |
| 501 | |
| 502 | /** |
| 503 | * dev_remove_offload - remove packet offload handler |
| 504 | * @po: packet offload declaration |
| 505 | * |
| 506 | * Remove a packet offload handler that was previously added to the kernel |
| 507 | * offload handlers by dev_add_offload(). The passed &offload_type is |
| 508 | * removed from the kernel lists and can be freed or reused once this |
| 509 | * function returns. |
| 510 | * |
| 511 | * This call sleeps to guarantee that no CPU is looking at the packet |
| 512 | * type after return. |
| 513 | */ |
| 514 | void dev_remove_offload(struct packet_offload *po) |
| 515 | { |
| 516 | __dev_remove_offload(po); |
| 517 | |
| 518 | synchronize_net(); |
| 519 | } |
| 520 | EXPORT_SYMBOL(dev_remove_offload); |
| 521 | |
| 522 | /****************************************************************************** |
| 523 | |
| 524 | Device Boot-time Settings Routines |
| 525 | |
| 526 | *******************************************************************************/ |
| 527 | |
| 528 | /* Boot time configuration table */ |
| 529 | static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; |
| 530 | |
| 531 | /** |
| 532 | * netdev_boot_setup_add - add new setup entry |
| 533 | * @name: name of the device |
| 534 | * @map: configured settings for the device |
| 535 | * |
| 536 | * Adds new setup entry to the dev_boot_setup list. The function |
| 537 | * returns 0 on error and 1 on success. This is a generic routine to |
| 538 | * all netdevices. |
| 539 | */ |
| 540 | static int netdev_boot_setup_add(char *name, struct ifmap *map) |
| 541 | { |
| 542 | struct netdev_boot_setup *s; |
| 543 | int i; |
| 544 | |
| 545 | s = dev_boot_setup; |
| 546 | for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { |
| 547 | if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { |
| 548 | memset(s[i].name, 0, sizeof(s[i].name)); |
| 549 | strlcpy(s[i].name, name, IFNAMSIZ); |
| 550 | memcpy(&s[i].map, map, sizeof(s[i].map)); |
| 551 | break; |
| 552 | } |
| 553 | } |
| 554 | |
| 555 | return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; |
| 556 | } |
| 557 | |
| 558 | /** |
| 559 | * netdev_boot_setup_check - check boot time settings |
| 560 | * @dev: the netdevice |
| 561 | * |
| 562 | * Check boot time settings for the device. |
| 563 | * The found settings are set for the device to be used |
| 564 | * later in the device probing. |
| 565 | * Returns 0 if no settings found, 1 if they are. |
| 566 | */ |
| 567 | int netdev_boot_setup_check(struct net_device *dev) |
| 568 | { |
| 569 | struct netdev_boot_setup *s = dev_boot_setup; |
| 570 | int i; |
| 571 | |
| 572 | for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { |
| 573 | if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && |
| 574 | !strcmp(dev->name, s[i].name)) { |
| 575 | dev->irq = s[i].map.irq; |
| 576 | dev->base_addr = s[i].map.base_addr; |
| 577 | dev->mem_start = s[i].map.mem_start; |
| 578 | dev->mem_end = s[i].map.mem_end; |
| 579 | return 1; |
| 580 | } |
| 581 | } |
| 582 | return 0; |
| 583 | } |
| 584 | EXPORT_SYMBOL(netdev_boot_setup_check); |
| 585 | |
| 586 | |
| 587 | /** |
| 588 | * netdev_boot_base - get address from boot time settings |
| 589 | * @prefix: prefix for network device |
| 590 | * @unit: id for network device |
| 591 | * |
| 592 | * Check boot time settings for the base address of device. |
| 593 | * The found settings are set for the device to be used |
| 594 | * later in the device probing. |
| 595 | * Returns 0 if no settings found. |
| 596 | */ |
| 597 | unsigned long netdev_boot_base(const char *prefix, int unit) |
| 598 | { |
| 599 | const struct netdev_boot_setup *s = dev_boot_setup; |
| 600 | char name[IFNAMSIZ]; |
| 601 | int i; |
| 602 | |
| 603 | sprintf(name, "%s%d", prefix, unit); |
| 604 | |
| 605 | /* |
| 606 | * If device already registered then return base of 1 |
| 607 | * to indicate not to probe for this interface |
| 608 | */ |
| 609 | if (__dev_get_by_name(&init_net, name)) |
| 610 | return 1; |
| 611 | |
| 612 | for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) |
| 613 | if (!strcmp(name, s[i].name)) |
| 614 | return s[i].map.base_addr; |
| 615 | return 0; |
| 616 | } |
| 617 | |
| 618 | /* |
| 619 | * Saves at boot time configured settings for any netdevice. |
| 620 | */ |
| 621 | int __init netdev_boot_setup(char *str) |
| 622 | { |
| 623 | int ints[5]; |
| 624 | struct ifmap map; |
| 625 | |
| 626 | str = get_options(str, ARRAY_SIZE(ints), ints); |
| 627 | if (!str || !*str) |
| 628 | return 0; |
| 629 | |
| 630 | /* Save settings */ |
| 631 | memset(&map, 0, sizeof(map)); |
| 632 | if (ints[0] > 0) |
| 633 | map.irq = ints[1]; |
| 634 | if (ints[0] > 1) |
| 635 | map.base_addr = ints[2]; |
| 636 | if (ints[0] > 2) |
| 637 | map.mem_start = ints[3]; |
| 638 | if (ints[0] > 3) |
| 639 | map.mem_end = ints[4]; |
| 640 | |
| 641 | /* Add new entry to the list */ |
| 642 | return netdev_boot_setup_add(str, &map); |
| 643 | } |
| 644 | |
| 645 | __setup("netdev=", netdev_boot_setup); |
| 646 | |
| 647 | /******************************************************************************* |
| 648 | |
| 649 | Device Interface Subroutines |
| 650 | |
| 651 | *******************************************************************************/ |
| 652 | |
| 653 | /** |
| 654 | * __dev_get_by_name - find a device by its name |
| 655 | * @net: the applicable net namespace |
| 656 | * @name: name to find |
| 657 | * |
| 658 | * Find an interface by name. Must be called under RTNL semaphore |
| 659 | * or @dev_base_lock. If the name is found a pointer to the device |
| 660 | * is returned. If the name is not found then %NULL is returned. The |
| 661 | * reference counters are not incremented so the caller must be |
| 662 | * careful with locks. |
| 663 | */ |
| 664 | |
| 665 | struct net_device *__dev_get_by_name(struct net *net, const char *name) |
| 666 | { |
| 667 | struct net_device *dev; |
| 668 | struct hlist_head *head = dev_name_hash(net, name); |
| 669 | |
| 670 | hlist_for_each_entry(dev, head, name_hlist) |
| 671 | if (!strncmp(dev->name, name, IFNAMSIZ)) |
| 672 | return dev; |
| 673 | |
| 674 | return NULL; |
| 675 | } |
| 676 | EXPORT_SYMBOL(__dev_get_by_name); |
| 677 | |
| 678 | /** |
| 679 | * dev_get_by_name_rcu - find a device by its name |
| 680 | * @net: the applicable net namespace |
| 681 | * @name: name to find |
| 682 | * |
| 683 | * Find an interface by name. |
| 684 | * If the name is found a pointer to the device is returned. |
| 685 | * If the name is not found then %NULL is returned. |
| 686 | * The reference counters are not incremented so the caller must be |
| 687 | * careful with locks. The caller must hold RCU lock. |
| 688 | */ |
| 689 | |
| 690 | struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) |
| 691 | { |
| 692 | struct net_device *dev; |
| 693 | struct hlist_head *head = dev_name_hash(net, name); |
| 694 | |
| 695 | hlist_for_each_entry_rcu(dev, head, name_hlist) |
| 696 | if (!strncmp(dev->name, name, IFNAMSIZ)) |
| 697 | return dev; |
| 698 | |
| 699 | return NULL; |
| 700 | } |
| 701 | EXPORT_SYMBOL(dev_get_by_name_rcu); |
| 702 | |
| 703 | /** |
| 704 | * dev_get_by_name - find a device by its name |
| 705 | * @net: the applicable net namespace |
| 706 | * @name: name to find |
| 707 | * |
| 708 | * Find an interface by name. This can be called from any |
| 709 | * context and does its own locking. The returned handle has |
| 710 | * the usage count incremented and the caller must use dev_put() to |
| 711 | * release it when it is no longer needed. %NULL is returned if no |
| 712 | * matching device is found. |
| 713 | */ |
| 714 | |
| 715 | struct net_device *dev_get_by_name(struct net *net, const char *name) |
| 716 | { |
| 717 | struct net_device *dev; |
| 718 | |
| 719 | rcu_read_lock(); |
| 720 | dev = dev_get_by_name_rcu(net, name); |
| 721 | if (dev) |
| 722 | dev_hold(dev); |
| 723 | rcu_read_unlock(); |
| 724 | return dev; |
| 725 | } |
| 726 | EXPORT_SYMBOL(dev_get_by_name); |
| 727 | |
| 728 | /** |
| 729 | * __dev_get_by_index - find a device by its ifindex |
| 730 | * @net: the applicable net namespace |
| 731 | * @ifindex: index of device |
| 732 | * |
| 733 | * Search for an interface by index. Returns %NULL if the device |
| 734 | * is not found or a pointer to the device. The device has not |
| 735 | * had its reference counter increased so the caller must be careful |
| 736 | * about locking. The caller must hold either the RTNL semaphore |
| 737 | * or @dev_base_lock. |
| 738 | */ |
| 739 | |
| 740 | struct net_device *__dev_get_by_index(struct net *net, int ifindex) |
| 741 | { |
| 742 | struct net_device *dev; |
| 743 | struct hlist_head *head = dev_index_hash(net, ifindex); |
| 744 | |
| 745 | hlist_for_each_entry(dev, head, index_hlist) |
| 746 | if (dev->ifindex == ifindex) |
| 747 | return dev; |
| 748 | |
| 749 | return NULL; |
| 750 | } |
| 751 | EXPORT_SYMBOL(__dev_get_by_index); |
| 752 | |
| 753 | /** |
| 754 | * dev_get_by_index_rcu - find a device by its ifindex |
| 755 | * @net: the applicable net namespace |
| 756 | * @ifindex: index of device |
| 757 | * |
| 758 | * Search for an interface by index. Returns %NULL if the device |
| 759 | * is not found or a pointer to the device. The device has not |
| 760 | * had its reference counter increased so the caller must be careful |
| 761 | * about locking. The caller must hold RCU lock. |
| 762 | */ |
| 763 | |
| 764 | struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) |
| 765 | { |
| 766 | struct net_device *dev; |
| 767 | struct hlist_head *head = dev_index_hash(net, ifindex); |
| 768 | |
| 769 | hlist_for_each_entry_rcu(dev, head, index_hlist) |
| 770 | if (dev->ifindex == ifindex) |
| 771 | return dev; |
| 772 | |
| 773 | return NULL; |
| 774 | } |
| 775 | EXPORT_SYMBOL(dev_get_by_index_rcu); |
| 776 | |
| 777 | |
| 778 | /** |
| 779 | * dev_get_by_index - find a device by its ifindex |
| 780 | * @net: the applicable net namespace |
| 781 | * @ifindex: index of device |
| 782 | * |
| 783 | * Search for an interface by index. Returns NULL if the device |
| 784 | * is not found or a pointer to the device. The device returned has |
| 785 | * had a reference added and the pointer is safe until the user calls |
| 786 | * dev_put to indicate they have finished with it. |
| 787 | */ |
| 788 | |
| 789 | struct net_device *dev_get_by_index(struct net *net, int ifindex) |
| 790 | { |
| 791 | struct net_device *dev; |
| 792 | |
| 793 | rcu_read_lock(); |
| 794 | dev = dev_get_by_index_rcu(net, ifindex); |
| 795 | if (dev) |
| 796 | dev_hold(dev); |
| 797 | rcu_read_unlock(); |
| 798 | return dev; |
| 799 | } |
| 800 | EXPORT_SYMBOL(dev_get_by_index); |
| 801 | |
| 802 | /** |
| 803 | * netdev_get_name - get a netdevice name, knowing its ifindex. |
| 804 | * @net: network namespace |
| 805 | * @name: a pointer to the buffer where the name will be stored. |
| 806 | * @ifindex: the ifindex of the interface to get the name from. |
| 807 | * |
| 808 | * The use of raw_seqcount_begin() and cond_resched() before |
| 809 | * retrying is required as we want to give the writers a chance |
| 810 | * to complete when CONFIG_PREEMPT is not set. |
| 811 | */ |
| 812 | int netdev_get_name(struct net *net, char *name, int ifindex) |
| 813 | { |
| 814 | struct net_device *dev; |
| 815 | unsigned int seq; |
| 816 | |
| 817 | retry: |
| 818 | seq = raw_seqcount_begin(&devnet_rename_seq); |
| 819 | rcu_read_lock(); |
| 820 | dev = dev_get_by_index_rcu(net, ifindex); |
| 821 | if (!dev) { |
| 822 | rcu_read_unlock(); |
| 823 | return -ENODEV; |
| 824 | } |
| 825 | |
| 826 | strcpy(name, dev->name); |
| 827 | rcu_read_unlock(); |
| 828 | if (read_seqcount_retry(&devnet_rename_seq, seq)) { |
| 829 | cond_resched(); |
| 830 | goto retry; |
| 831 | } |
| 832 | |
| 833 | return 0; |
| 834 | } |
| 835 | |
| 836 | /** |
| 837 | * dev_getbyhwaddr_rcu - find a device by its hardware address |
| 838 | * @net: the applicable net namespace |
| 839 | * @type: media type of device |
| 840 | * @ha: hardware address |
| 841 | * |
| 842 | * Search for an interface by MAC address. Returns NULL if the device |
| 843 | * is not found or a pointer to the device. |
| 844 | * The caller must hold RCU or RTNL. |
| 845 | * The returned device has not had its ref count increased |
| 846 | * and the caller must therefore be careful about locking |
| 847 | * |
| 848 | */ |
| 849 | |
| 850 | struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, |
| 851 | const char *ha) |
| 852 | { |
| 853 | struct net_device *dev; |
| 854 | |
| 855 | for_each_netdev_rcu(net, dev) |
| 856 | if (dev->type == type && |
| 857 | !memcmp(dev->dev_addr, ha, dev->addr_len)) |
| 858 | return dev; |
| 859 | |
| 860 | return NULL; |
| 861 | } |
| 862 | EXPORT_SYMBOL(dev_getbyhwaddr_rcu); |
| 863 | |
| 864 | struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type) |
| 865 | { |
| 866 | struct net_device *dev; |
| 867 | |
| 868 | ASSERT_RTNL(); |
| 869 | for_each_netdev(net, dev) |
| 870 | if (dev->type == type) |
| 871 | return dev; |
| 872 | |
| 873 | return NULL; |
| 874 | } |
| 875 | EXPORT_SYMBOL(__dev_getfirstbyhwtype); |
| 876 | |
| 877 | struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) |
| 878 | { |
| 879 | struct net_device *dev, *ret = NULL; |
| 880 | |
| 881 | rcu_read_lock(); |
| 882 | for_each_netdev_rcu(net, dev) |
| 883 | if (dev->type == type) { |
| 884 | dev_hold(dev); |
| 885 | ret = dev; |
| 886 | break; |
| 887 | } |
| 888 | rcu_read_unlock(); |
| 889 | return ret; |
| 890 | } |
| 891 | EXPORT_SYMBOL(dev_getfirstbyhwtype); |
| 892 | |
| 893 | /** |
| 894 | * dev_get_by_flags_rcu - find any device with given flags |
| 895 | * @net: the applicable net namespace |
| 896 | * @if_flags: IFF_* values |
| 897 | * @mask: bitmask of bits in if_flags to check |
| 898 | * |
| 899 | * Search for any interface with the given flags. Returns NULL if a device |
| 900 | * is not found or a pointer to the device. Must be called inside |
| 901 | * rcu_read_lock(), and result refcount is unchanged. |
| 902 | */ |
| 903 | |
| 904 | struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags, |
| 905 | unsigned short mask) |
| 906 | { |
| 907 | struct net_device *dev, *ret; |
| 908 | |
| 909 | ret = NULL; |
| 910 | for_each_netdev_rcu(net, dev) { |
| 911 | if (((dev->flags ^ if_flags) & mask) == 0) { |
| 912 | ret = dev; |
| 913 | break; |
| 914 | } |
| 915 | } |
| 916 | return ret; |
| 917 | } |
| 918 | EXPORT_SYMBOL(dev_get_by_flags_rcu); |
| 919 | |
| 920 | /** |
| 921 | * dev_valid_name - check if name is okay for network device |
| 922 | * @name: name string |
| 923 | * |
| 924 | * Network device names need to be valid file names to |
| 925 | * to allow sysfs to work. We also disallow any kind of |
| 926 | * whitespace. |
| 927 | */ |
| 928 | bool dev_valid_name(const char *name) |
| 929 | { |
| 930 | if (*name == '\0') |
| 931 | return false; |
| 932 | if (strlen(name) >= IFNAMSIZ) |
| 933 | return false; |
| 934 | if (!strcmp(name, ".") || !strcmp(name, "..")) |
| 935 | return false; |
| 936 | |
| 937 | while (*name) { |
| 938 | if (*name == '/' || isspace(*name)) |
| 939 | return false; |
| 940 | name++; |
| 941 | } |
| 942 | return true; |
| 943 | } |
| 944 | EXPORT_SYMBOL(dev_valid_name); |
| 945 | |
| 946 | /** |
| 947 | * __dev_alloc_name - allocate a name for a device |
| 948 | * @net: network namespace to allocate the device name in |
| 949 | * @name: name format string |
| 950 | * @buf: scratch buffer and result name string |
| 951 | * |
| 952 | * Passed a format string - eg "lt%d" it will try and find a suitable |
| 953 | * id. It scans list of devices to build up a free map, then chooses |
| 954 | * the first empty slot. The caller must hold the dev_base or rtnl lock |
| 955 | * while allocating the name and adding the device in order to avoid |
| 956 | * duplicates. |
| 957 | * Limited to bits_per_byte * page size devices (ie 32K on most platforms). |
| 958 | * Returns the number of the unit assigned or a negative errno code. |
| 959 | */ |
| 960 | |
| 961 | static int __dev_alloc_name(struct net *net, const char *name, char *buf) |
| 962 | { |
| 963 | int i = 0; |
| 964 | const char *p; |
| 965 | const int max_netdevices = 8*PAGE_SIZE; |
| 966 | unsigned long *inuse; |
| 967 | struct net_device *d; |
| 968 | |
| 969 | p = strnchr(name, IFNAMSIZ-1, '%'); |
| 970 | if (p) { |
| 971 | /* |
| 972 | * Verify the string as this thing may have come from |
| 973 | * the user. There must be either one "%d" and no other "%" |
| 974 | * characters. |
| 975 | */ |
| 976 | if (p[1] != 'd' || strchr(p + 2, '%')) |
| 977 | return -EINVAL; |
| 978 | |
| 979 | /* Use one page as a bit array of possible slots */ |
| 980 | inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); |
| 981 | if (!inuse) |
| 982 | return -ENOMEM; |
| 983 | |
| 984 | for_each_netdev(net, d) { |
| 985 | if (!sscanf(d->name, name, &i)) |
| 986 | continue; |
| 987 | if (i < 0 || i >= max_netdevices) |
| 988 | continue; |
| 989 | |
| 990 | /* avoid cases where sscanf is not exact inverse of printf */ |
| 991 | snprintf(buf, IFNAMSIZ, name, i); |
| 992 | if (!strncmp(buf, d->name, IFNAMSIZ)) |
| 993 | set_bit(i, inuse); |
| 994 | } |
| 995 | |
| 996 | i = find_first_zero_bit(inuse, max_netdevices); |
| 997 | free_page((unsigned long) inuse); |
| 998 | } |
| 999 | |
| 1000 | if (buf != name) |
| 1001 | snprintf(buf, IFNAMSIZ, name, i); |
| 1002 | if (!__dev_get_by_name(net, buf)) |
| 1003 | return i; |
| 1004 | |
| 1005 | /* It is possible to run out of possible slots |
| 1006 | * when the name is long and there isn't enough space left |
| 1007 | * for the digits, or if all bits are used. |
| 1008 | */ |
| 1009 | return -ENFILE; |
| 1010 | } |
| 1011 | |
| 1012 | /** |
| 1013 | * dev_alloc_name - allocate a name for a device |
| 1014 | * @dev: device |
| 1015 | * @name: name format string |
| 1016 | * |
| 1017 | * Passed a format string - eg "lt%d" it will try and find a suitable |
| 1018 | * id. It scans list of devices to build up a free map, then chooses |
| 1019 | * the first empty slot. The caller must hold the dev_base or rtnl lock |
| 1020 | * while allocating the name and adding the device in order to avoid |
| 1021 | * duplicates. |
| 1022 | * Limited to bits_per_byte * page size devices (ie 32K on most platforms). |
| 1023 | * Returns the number of the unit assigned or a negative errno code. |
| 1024 | */ |
| 1025 | |
| 1026 | int dev_alloc_name(struct net_device *dev, const char *name) |
| 1027 | { |
| 1028 | char buf[IFNAMSIZ]; |
| 1029 | struct net *net; |
| 1030 | int ret; |
| 1031 | |
| 1032 | BUG_ON(!dev_net(dev)); |
| 1033 | net = dev_net(dev); |
| 1034 | ret = __dev_alloc_name(net, name, buf); |
| 1035 | if (ret >= 0) |
| 1036 | strlcpy(dev->name, buf, IFNAMSIZ); |
| 1037 | return ret; |
| 1038 | } |
| 1039 | EXPORT_SYMBOL(dev_alloc_name); |
| 1040 | |
| 1041 | static int dev_alloc_name_ns(struct net *net, |
| 1042 | struct net_device *dev, |
| 1043 | const char *name) |
| 1044 | { |
| 1045 | char buf[IFNAMSIZ]; |
| 1046 | int ret; |
| 1047 | |
| 1048 | ret = __dev_alloc_name(net, name, buf); |
| 1049 | if (ret >= 0) |
| 1050 | strlcpy(dev->name, buf, IFNAMSIZ); |
| 1051 | return ret; |
| 1052 | } |
| 1053 | |
| 1054 | static int dev_get_valid_name(struct net *net, |
| 1055 | struct net_device *dev, |
| 1056 | const char *name) |
| 1057 | { |
| 1058 | BUG_ON(!net); |
| 1059 | |
| 1060 | if (!dev_valid_name(name)) |
| 1061 | return -EINVAL; |
| 1062 | |
| 1063 | if (strchr(name, '%')) |
| 1064 | return dev_alloc_name_ns(net, dev, name); |
| 1065 | else if (__dev_get_by_name(net, name)) |
| 1066 | return -EEXIST; |
| 1067 | else if (dev->name != name) |
| 1068 | strlcpy(dev->name, name, IFNAMSIZ); |
| 1069 | |
| 1070 | return 0; |
| 1071 | } |
| 1072 | |
| 1073 | /** |
| 1074 | * dev_change_name - change name of a device |
| 1075 | * @dev: device |
| 1076 | * @newname: name (or format string) must be at least IFNAMSIZ |
| 1077 | * |
| 1078 | * Change name of a device, can pass format strings "eth%d". |
| 1079 | * for wildcarding. |
| 1080 | */ |
| 1081 | int dev_change_name(struct net_device *dev, const char *newname) |
| 1082 | { |
| 1083 | char oldname[IFNAMSIZ]; |
| 1084 | int err = 0; |
| 1085 | int ret; |
| 1086 | struct net *net; |
| 1087 | |
| 1088 | ASSERT_RTNL(); |
| 1089 | BUG_ON(!dev_net(dev)); |
| 1090 | |
| 1091 | net = dev_net(dev); |
| 1092 | if (dev->flags & IFF_UP) |
| 1093 | return -EBUSY; |
| 1094 | |
| 1095 | write_seqcount_begin(&devnet_rename_seq); |
| 1096 | |
| 1097 | if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { |
| 1098 | write_seqcount_end(&devnet_rename_seq); |
| 1099 | return 0; |
| 1100 | } |
| 1101 | |
| 1102 | memcpy(oldname, dev->name, IFNAMSIZ); |
| 1103 | |
| 1104 | err = dev_get_valid_name(net, dev, newname); |
| 1105 | if (err < 0) { |
| 1106 | write_seqcount_end(&devnet_rename_seq); |
| 1107 | return err; |
| 1108 | } |
| 1109 | |
| 1110 | rollback: |
| 1111 | ret = device_rename(&dev->dev, dev->name); |
| 1112 | if (ret) { |
| 1113 | memcpy(dev->name, oldname, IFNAMSIZ); |
| 1114 | write_seqcount_end(&devnet_rename_seq); |
| 1115 | return ret; |
| 1116 | } |
| 1117 | |
| 1118 | write_seqcount_end(&devnet_rename_seq); |
| 1119 | |
| 1120 | write_lock_bh(&dev_base_lock); |
| 1121 | hlist_del_rcu(&dev->name_hlist); |
| 1122 | write_unlock_bh(&dev_base_lock); |
| 1123 | |
| 1124 | synchronize_rcu(); |
| 1125 | |
| 1126 | write_lock_bh(&dev_base_lock); |
| 1127 | hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); |
| 1128 | write_unlock_bh(&dev_base_lock); |
| 1129 | |
| 1130 | ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); |
| 1131 | ret = notifier_to_errno(ret); |
| 1132 | |
| 1133 | if (ret) { |
| 1134 | /* err >= 0 after dev_alloc_name() or stores the first errno */ |
| 1135 | if (err >= 0) { |
| 1136 | err = ret; |
| 1137 | write_seqcount_begin(&devnet_rename_seq); |
| 1138 | memcpy(dev->name, oldname, IFNAMSIZ); |
| 1139 | goto rollback; |
| 1140 | } else { |
| 1141 | pr_err("%s: name change rollback failed: %d\n", |
| 1142 | dev->name, ret); |
| 1143 | } |
| 1144 | } |
| 1145 | |
| 1146 | return err; |
| 1147 | } |
| 1148 | |
| 1149 | /** |
| 1150 | * dev_set_alias - change ifalias of a device |
| 1151 | * @dev: device |
| 1152 | * @alias: name up to IFALIASZ |
| 1153 | * @len: limit of bytes to copy from info |
| 1154 | * |
| 1155 | * Set ifalias for a device, |
| 1156 | */ |
| 1157 | int dev_set_alias(struct net_device *dev, const char *alias, size_t len) |
| 1158 | { |
| 1159 | char *new_ifalias; |
| 1160 | |
| 1161 | ASSERT_RTNL(); |
| 1162 | |
| 1163 | if (len >= IFALIASZ) |
| 1164 | return -EINVAL; |
| 1165 | |
| 1166 | if (!len) { |
| 1167 | kfree(dev->ifalias); |
| 1168 | dev->ifalias = NULL; |
| 1169 | return 0; |
| 1170 | } |
| 1171 | |
| 1172 | new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL); |
| 1173 | if (!new_ifalias) |
| 1174 | return -ENOMEM; |
| 1175 | dev->ifalias = new_ifalias; |
| 1176 | |
| 1177 | strlcpy(dev->ifalias, alias, len+1); |
| 1178 | return len; |
| 1179 | } |
| 1180 | |
| 1181 | |
| 1182 | /** |
| 1183 | * netdev_features_change - device changes features |
| 1184 | * @dev: device to cause notification |
| 1185 | * |
| 1186 | * Called to indicate a device has changed features. |
| 1187 | */ |
| 1188 | void netdev_features_change(struct net_device *dev) |
| 1189 | { |
| 1190 | call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); |
| 1191 | } |
| 1192 | EXPORT_SYMBOL(netdev_features_change); |
| 1193 | |
| 1194 | /** |
| 1195 | * netdev_state_change - device changes state |
| 1196 | * @dev: device to cause notification |
| 1197 | * |
| 1198 | * Called to indicate a device has changed state. This function calls |
| 1199 | * the notifier chains for netdev_chain and sends a NEWLINK message |
| 1200 | * to the routing socket. |
| 1201 | */ |
| 1202 | void netdev_state_change(struct net_device *dev) |
| 1203 | { |
| 1204 | if (dev->flags & IFF_UP) { |
| 1205 | call_netdevice_notifiers(NETDEV_CHANGE, dev); |
| 1206 | rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL); |
| 1207 | } |
| 1208 | } |
| 1209 | EXPORT_SYMBOL(netdev_state_change); |
| 1210 | |
| 1211 | /** |
| 1212 | * netdev_notify_peers - notify network peers about existence of @dev |
| 1213 | * @dev: network device |
| 1214 | * |
| 1215 | * Generate traffic such that interested network peers are aware of |
| 1216 | * @dev, such as by generating a gratuitous ARP. This may be used when |
| 1217 | * a device wants to inform the rest of the network about some sort of |
| 1218 | * reconfiguration such as a failover event or virtual machine |
| 1219 | * migration. |
| 1220 | */ |
| 1221 | void netdev_notify_peers(struct net_device *dev) |
| 1222 | { |
| 1223 | rtnl_lock(); |
| 1224 | call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); |
| 1225 | rtnl_unlock(); |
| 1226 | } |
| 1227 | EXPORT_SYMBOL(netdev_notify_peers); |
| 1228 | |
| 1229 | static int __dev_open(struct net_device *dev) |
| 1230 | { |
| 1231 | const struct net_device_ops *ops = dev->netdev_ops; |
| 1232 | int ret; |
| 1233 | |
| 1234 | ASSERT_RTNL(); |
| 1235 | |
| 1236 | if (!netif_device_present(dev)) |
| 1237 | return -ENODEV; |
| 1238 | |
| 1239 | /* Block netpoll from trying to do any rx path servicing. |
| 1240 | * If we don't do this there is a chance ndo_poll_controller |
| 1241 | * or ndo_poll may be running while we open the device |
| 1242 | */ |
| 1243 | netpoll_rx_disable(dev); |
| 1244 | |
| 1245 | ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev); |
| 1246 | ret = notifier_to_errno(ret); |
| 1247 | if (ret) |
| 1248 | return ret; |
| 1249 | |
| 1250 | set_bit(__LINK_STATE_START, &dev->state); |
| 1251 | |
| 1252 | if (ops->ndo_validate_addr) |
| 1253 | ret = ops->ndo_validate_addr(dev); |
| 1254 | |
| 1255 | if (!ret && ops->ndo_open) |
| 1256 | ret = ops->ndo_open(dev); |
| 1257 | |
| 1258 | netpoll_rx_enable(dev); |
| 1259 | |
| 1260 | if (ret) |
| 1261 | clear_bit(__LINK_STATE_START, &dev->state); |
| 1262 | else { |
| 1263 | dev->flags |= IFF_UP; |
| 1264 | net_dmaengine_get(); |
| 1265 | dev_set_rx_mode(dev); |
| 1266 | dev_activate(dev); |
| 1267 | add_device_randomness(dev->dev_addr, dev->addr_len); |
| 1268 | } |
| 1269 | |
| 1270 | return ret; |
| 1271 | } |
| 1272 | |
| 1273 | /** |
| 1274 | * dev_open - prepare an interface for use. |
| 1275 | * @dev: device to open |
| 1276 | * |
| 1277 | * Takes a device from down to up state. The device's private open |
| 1278 | * function is invoked and then the multicast lists are loaded. Finally |
| 1279 | * the device is moved into the up state and a %NETDEV_UP message is |
| 1280 | * sent to the netdev notifier chain. |
| 1281 | * |
| 1282 | * Calling this function on an active interface is a nop. On a failure |
| 1283 | * a negative errno code is returned. |
| 1284 | */ |
| 1285 | int dev_open(struct net_device *dev) |
| 1286 | { |
| 1287 | int ret; |
| 1288 | |
| 1289 | if (dev->flags & IFF_UP) |
| 1290 | return 0; |
| 1291 | |
| 1292 | ret = __dev_open(dev); |
| 1293 | if (ret < 0) |
| 1294 | return ret; |
| 1295 | |
| 1296 | rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); |
| 1297 | call_netdevice_notifiers(NETDEV_UP, dev); |
| 1298 | |
| 1299 | return ret; |
| 1300 | } |
| 1301 | EXPORT_SYMBOL(dev_open); |
| 1302 | |
| 1303 | static int __dev_close_many(struct list_head *head) |
| 1304 | { |
| 1305 | struct net_device *dev; |
| 1306 | |
| 1307 | ASSERT_RTNL(); |
| 1308 | might_sleep(); |
| 1309 | |
| 1310 | list_for_each_entry(dev, head, close_list) { |
| 1311 | call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); |
| 1312 | |
| 1313 | clear_bit(__LINK_STATE_START, &dev->state); |
| 1314 | |
| 1315 | /* Synchronize to scheduled poll. We cannot touch poll list, it |
| 1316 | * can be even on different cpu. So just clear netif_running(). |
| 1317 | * |
| 1318 | * dev->stop() will invoke napi_disable() on all of it's |
| 1319 | * napi_struct instances on this device. |
| 1320 | */ |
| 1321 | smp_mb__after_clear_bit(); /* Commit netif_running(). */ |
| 1322 | } |
| 1323 | |
| 1324 | dev_deactivate_many(head); |
| 1325 | |
| 1326 | list_for_each_entry(dev, head, close_list) { |
| 1327 | const struct net_device_ops *ops = dev->netdev_ops; |
| 1328 | |
| 1329 | /* |
| 1330 | * Call the device specific close. This cannot fail. |
| 1331 | * Only if device is UP |
| 1332 | * |
| 1333 | * We allow it to be called even after a DETACH hot-plug |
| 1334 | * event. |
| 1335 | */ |
| 1336 | if (ops->ndo_stop) |
| 1337 | ops->ndo_stop(dev); |
| 1338 | |
| 1339 | dev->flags &= ~IFF_UP; |
| 1340 | net_dmaengine_put(); |
| 1341 | } |
| 1342 | |
| 1343 | return 0; |
| 1344 | } |
| 1345 | |
| 1346 | static int __dev_close(struct net_device *dev) |
| 1347 | { |
| 1348 | int retval; |
| 1349 | LIST_HEAD(single); |
| 1350 | |
| 1351 | /* Temporarily disable netpoll until the interface is down */ |
| 1352 | netpoll_rx_disable(dev); |
| 1353 | |
| 1354 | list_add(&dev->close_list, &single); |
| 1355 | retval = __dev_close_many(&single); |
| 1356 | list_del(&single); |
| 1357 | |
| 1358 | netpoll_rx_enable(dev); |
| 1359 | return retval; |
| 1360 | } |
| 1361 | |
| 1362 | static int dev_close_many(struct list_head *head) |
| 1363 | { |
| 1364 | struct net_device *dev, *tmp; |
| 1365 | |
| 1366 | /* Remove the devices that don't need to be closed */ |
| 1367 | list_for_each_entry_safe(dev, tmp, head, close_list) |
| 1368 | if (!(dev->flags & IFF_UP)) |
| 1369 | list_del_init(&dev->close_list); |
| 1370 | |
| 1371 | __dev_close_many(head); |
| 1372 | |
| 1373 | list_for_each_entry_safe(dev, tmp, head, close_list) { |
| 1374 | rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); |
| 1375 | call_netdevice_notifiers(NETDEV_DOWN, dev); |
| 1376 | list_del_init(&dev->close_list); |
| 1377 | } |
| 1378 | |
| 1379 | return 0; |
| 1380 | } |
| 1381 | |
| 1382 | /** |
| 1383 | * dev_close - shutdown an interface. |
| 1384 | * @dev: device to shutdown |
| 1385 | * |
| 1386 | * This function moves an active device into down state. A |
| 1387 | * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device |
| 1388 | * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier |
| 1389 | * chain. |
| 1390 | */ |
| 1391 | int dev_close(struct net_device *dev) |
| 1392 | { |
| 1393 | if (dev->flags & IFF_UP) { |
| 1394 | LIST_HEAD(single); |
| 1395 | |
| 1396 | /* Block netpoll rx while the interface is going down */ |
| 1397 | netpoll_rx_disable(dev); |
| 1398 | |
| 1399 | list_add(&dev->close_list, &single); |
| 1400 | dev_close_many(&single); |
| 1401 | list_del(&single); |
| 1402 | |
| 1403 | netpoll_rx_enable(dev); |
| 1404 | } |
| 1405 | return 0; |
| 1406 | } |
| 1407 | EXPORT_SYMBOL(dev_close); |
| 1408 | |
| 1409 | |
| 1410 | /** |
| 1411 | * dev_disable_lro - disable Large Receive Offload on a device |
| 1412 | * @dev: device |
| 1413 | * |
| 1414 | * Disable Large Receive Offload (LRO) on a net device. Must be |
| 1415 | * called under RTNL. This is needed if received packets may be |
| 1416 | * forwarded to another interface. |
| 1417 | */ |
| 1418 | void dev_disable_lro(struct net_device *dev) |
| 1419 | { |
| 1420 | /* |
| 1421 | * If we're trying to disable lro on a vlan device |
| 1422 | * use the underlying physical device instead |
| 1423 | */ |
| 1424 | if (is_vlan_dev(dev)) |
| 1425 | dev = vlan_dev_real_dev(dev); |
| 1426 | |
| 1427 | /* the same for macvlan devices */ |
| 1428 | if (netif_is_macvlan(dev)) |
| 1429 | dev = macvlan_dev_real_dev(dev); |
| 1430 | |
| 1431 | dev->wanted_features &= ~NETIF_F_LRO; |
| 1432 | netdev_update_features(dev); |
| 1433 | |
| 1434 | if (unlikely(dev->features & NETIF_F_LRO)) |
| 1435 | netdev_WARN(dev, "failed to disable LRO!\n"); |
| 1436 | } |
| 1437 | EXPORT_SYMBOL(dev_disable_lro); |
| 1438 | |
| 1439 | static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, |
| 1440 | struct net_device *dev) |
| 1441 | { |
| 1442 | struct netdev_notifier_info info; |
| 1443 | |
| 1444 | netdev_notifier_info_init(&info, dev); |
| 1445 | return nb->notifier_call(nb, val, &info); |
| 1446 | } |
| 1447 | |
| 1448 | static int dev_boot_phase = 1; |
| 1449 | |
| 1450 | /** |
| 1451 | * register_netdevice_notifier - register a network notifier block |
| 1452 | * @nb: notifier |
| 1453 | * |
| 1454 | * Register a notifier to be called when network device events occur. |
| 1455 | * The notifier passed is linked into the kernel structures and must |
| 1456 | * not be reused until it has been unregistered. A negative errno code |
| 1457 | * is returned on a failure. |
| 1458 | * |
| 1459 | * When registered all registration and up events are replayed |
| 1460 | * to the new notifier to allow device to have a race free |
| 1461 | * view of the network device list. |
| 1462 | */ |
| 1463 | |
| 1464 | int register_netdevice_notifier(struct notifier_block *nb) |
| 1465 | { |
| 1466 | struct net_device *dev; |
| 1467 | struct net_device *last; |
| 1468 | struct net *net; |
| 1469 | int err; |
| 1470 | |
| 1471 | rtnl_lock(); |
| 1472 | err = raw_notifier_chain_register(&netdev_chain, nb); |
| 1473 | if (err) |
| 1474 | goto unlock; |
| 1475 | if (dev_boot_phase) |
| 1476 | goto unlock; |
| 1477 | for_each_net(net) { |
| 1478 | for_each_netdev(net, dev) { |
| 1479 | err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); |
| 1480 | err = notifier_to_errno(err); |
| 1481 | if (err) |
| 1482 | goto rollback; |
| 1483 | |
| 1484 | if (!(dev->flags & IFF_UP)) |
| 1485 | continue; |
| 1486 | |
| 1487 | call_netdevice_notifier(nb, NETDEV_UP, dev); |
| 1488 | } |
| 1489 | } |
| 1490 | |
| 1491 | unlock: |
| 1492 | rtnl_unlock(); |
| 1493 | return err; |
| 1494 | |
| 1495 | rollback: |
| 1496 | last = dev; |
| 1497 | for_each_net(net) { |
| 1498 | for_each_netdev(net, dev) { |
| 1499 | if (dev == last) |
| 1500 | goto outroll; |
| 1501 | |
| 1502 | if (dev->flags & IFF_UP) { |
| 1503 | call_netdevice_notifier(nb, NETDEV_GOING_DOWN, |
| 1504 | dev); |
| 1505 | call_netdevice_notifier(nb, NETDEV_DOWN, dev); |
| 1506 | } |
| 1507 | call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); |
| 1508 | } |
| 1509 | } |
| 1510 | |
| 1511 | outroll: |
| 1512 | raw_notifier_chain_unregister(&netdev_chain, nb); |
| 1513 | goto unlock; |
| 1514 | } |
| 1515 | EXPORT_SYMBOL(register_netdevice_notifier); |
| 1516 | |
| 1517 | /** |
| 1518 | * unregister_netdevice_notifier - unregister a network notifier block |
| 1519 | * @nb: notifier |
| 1520 | * |
| 1521 | * Unregister a notifier previously registered by |
| 1522 | * register_netdevice_notifier(). The notifier is unlinked into the |
| 1523 | * kernel structures and may then be reused. A negative errno code |
| 1524 | * is returned on a failure. |
| 1525 | * |
| 1526 | * After unregistering unregister and down device events are synthesized |
| 1527 | * for all devices on the device list to the removed notifier to remove |
| 1528 | * the need for special case cleanup code. |
| 1529 | */ |
| 1530 | |
| 1531 | int unregister_netdevice_notifier(struct notifier_block *nb) |
| 1532 | { |
| 1533 | struct net_device *dev; |
| 1534 | struct net *net; |
| 1535 | int err; |
| 1536 | |
| 1537 | rtnl_lock(); |
| 1538 | err = raw_notifier_chain_unregister(&netdev_chain, nb); |
| 1539 | if (err) |
| 1540 | goto unlock; |
| 1541 | |
| 1542 | for_each_net(net) { |
| 1543 | for_each_netdev(net, dev) { |
| 1544 | if (dev->flags & IFF_UP) { |
| 1545 | call_netdevice_notifier(nb, NETDEV_GOING_DOWN, |
| 1546 | dev); |
| 1547 | call_netdevice_notifier(nb, NETDEV_DOWN, dev); |
| 1548 | } |
| 1549 | call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); |
| 1550 | } |
| 1551 | } |
| 1552 | unlock: |
| 1553 | rtnl_unlock(); |
| 1554 | return err; |
| 1555 | } |
| 1556 | EXPORT_SYMBOL(unregister_netdevice_notifier); |
| 1557 | |
| 1558 | /** |
| 1559 | * call_netdevice_notifiers_info - call all network notifier blocks |
| 1560 | * @val: value passed unmodified to notifier function |
| 1561 | * @dev: net_device pointer passed unmodified to notifier function |
| 1562 | * @info: notifier information data |
| 1563 | * |
| 1564 | * Call all network notifier blocks. Parameters and return value |
| 1565 | * are as for raw_notifier_call_chain(). |
| 1566 | */ |
| 1567 | |
| 1568 | static int call_netdevice_notifiers_info(unsigned long val, |
| 1569 | struct net_device *dev, |
| 1570 | struct netdev_notifier_info *info) |
| 1571 | { |
| 1572 | ASSERT_RTNL(); |
| 1573 | netdev_notifier_info_init(info, dev); |
| 1574 | return raw_notifier_call_chain(&netdev_chain, val, info); |
| 1575 | } |
| 1576 | |
| 1577 | /** |
| 1578 | * call_netdevice_notifiers - call all network notifier blocks |
| 1579 | * @val: value passed unmodified to notifier function |
| 1580 | * @dev: net_device pointer passed unmodified to notifier function |
| 1581 | * |
| 1582 | * Call all network notifier blocks. Parameters and return value |
| 1583 | * are as for raw_notifier_call_chain(). |
| 1584 | */ |
| 1585 | |
| 1586 | int call_netdevice_notifiers(unsigned long val, struct net_device *dev) |
| 1587 | { |
| 1588 | struct netdev_notifier_info info; |
| 1589 | |
| 1590 | return call_netdevice_notifiers_info(val, dev, &info); |
| 1591 | } |
| 1592 | EXPORT_SYMBOL(call_netdevice_notifiers); |
| 1593 | |
| 1594 | static struct static_key netstamp_needed __read_mostly; |
| 1595 | #ifdef HAVE_JUMP_LABEL |
| 1596 | /* We are not allowed to call static_key_slow_dec() from irq context |
| 1597 | * If net_disable_timestamp() is called from irq context, defer the |
| 1598 | * static_key_slow_dec() calls. |
| 1599 | */ |
| 1600 | static atomic_t netstamp_needed_deferred; |
| 1601 | #endif |
| 1602 | |
| 1603 | void net_enable_timestamp(void) |
| 1604 | { |
| 1605 | #ifdef HAVE_JUMP_LABEL |
| 1606 | int deferred = atomic_xchg(&netstamp_needed_deferred, 0); |
| 1607 | |
| 1608 | if (deferred) { |
| 1609 | while (--deferred) |
| 1610 | static_key_slow_dec(&netstamp_needed); |
| 1611 | return; |
| 1612 | } |
| 1613 | #endif |
| 1614 | static_key_slow_inc(&netstamp_needed); |
| 1615 | } |
| 1616 | EXPORT_SYMBOL(net_enable_timestamp); |
| 1617 | |
| 1618 | void net_disable_timestamp(void) |
| 1619 | { |
| 1620 | #ifdef HAVE_JUMP_LABEL |
| 1621 | if (in_interrupt()) { |
| 1622 | atomic_inc(&netstamp_needed_deferred); |
| 1623 | return; |
| 1624 | } |
| 1625 | #endif |
| 1626 | static_key_slow_dec(&netstamp_needed); |
| 1627 | } |
| 1628 | EXPORT_SYMBOL(net_disable_timestamp); |
| 1629 | |
| 1630 | static inline void net_timestamp_set(struct sk_buff *skb) |
| 1631 | { |
| 1632 | skb->tstamp.tv64 = 0; |
| 1633 | if (static_key_false(&netstamp_needed)) |
| 1634 | __net_timestamp(skb); |
| 1635 | } |
| 1636 | |
| 1637 | #define net_timestamp_check(COND, SKB) \ |
| 1638 | if (static_key_false(&netstamp_needed)) { \ |
| 1639 | if ((COND) && !(SKB)->tstamp.tv64) \ |
| 1640 | __net_timestamp(SKB); \ |
| 1641 | } \ |
| 1642 | |
| 1643 | static inline bool is_skb_forwardable(struct net_device *dev, |
| 1644 | struct sk_buff *skb) |
| 1645 | { |
| 1646 | unsigned int len; |
| 1647 | |
| 1648 | if (!(dev->flags & IFF_UP)) |
| 1649 | return false; |
| 1650 | |
| 1651 | len = dev->mtu + dev->hard_header_len + VLAN_HLEN; |
| 1652 | if (skb->len <= len) |
| 1653 | return true; |
| 1654 | |
| 1655 | /* if TSO is enabled, we don't care about the length as the packet |
| 1656 | * could be forwarded without being segmented before |
| 1657 | */ |
| 1658 | if (skb_is_gso(skb)) |
| 1659 | return true; |
| 1660 | |
| 1661 | return false; |
| 1662 | } |
| 1663 | |
| 1664 | /** |
| 1665 | * dev_forward_skb - loopback an skb to another netif |
| 1666 | * |
| 1667 | * @dev: destination network device |
| 1668 | * @skb: buffer to forward |
| 1669 | * |
| 1670 | * return values: |
| 1671 | * NET_RX_SUCCESS (no congestion) |
| 1672 | * NET_RX_DROP (packet was dropped, but freed) |
| 1673 | * |
| 1674 | * dev_forward_skb can be used for injecting an skb from the |
| 1675 | * start_xmit function of one device into the receive queue |
| 1676 | * of another device. |
| 1677 | * |
| 1678 | * The receiving device may be in another namespace, so |
| 1679 | * we have to clear all information in the skb that could |
| 1680 | * impact namespace isolation. |
| 1681 | */ |
| 1682 | int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) |
| 1683 | { |
| 1684 | if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) { |
| 1685 | if (skb_copy_ubufs(skb, GFP_ATOMIC)) { |
| 1686 | atomic_long_inc(&dev->rx_dropped); |
| 1687 | kfree_skb(skb); |
| 1688 | return NET_RX_DROP; |
| 1689 | } |
| 1690 | } |
| 1691 | |
| 1692 | if (unlikely(!is_skb_forwardable(dev, skb))) { |
| 1693 | atomic_long_inc(&dev->rx_dropped); |
| 1694 | kfree_skb(skb); |
| 1695 | return NET_RX_DROP; |
| 1696 | } |
| 1697 | |
| 1698 | skb_scrub_packet(skb, true); |
| 1699 | skb->protocol = eth_type_trans(skb, dev); |
| 1700 | |
| 1701 | return netif_rx(skb); |
| 1702 | } |
| 1703 | EXPORT_SYMBOL_GPL(dev_forward_skb); |
| 1704 | |
| 1705 | static inline int deliver_skb(struct sk_buff *skb, |
| 1706 | struct packet_type *pt_prev, |
| 1707 | struct net_device *orig_dev) |
| 1708 | { |
| 1709 | if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) |
| 1710 | return -ENOMEM; |
| 1711 | atomic_inc(&skb->users); |
| 1712 | return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); |
| 1713 | } |
| 1714 | |
| 1715 | static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) |
| 1716 | { |
| 1717 | if (!ptype->af_packet_priv || !skb->sk) |
| 1718 | return false; |
| 1719 | |
| 1720 | if (ptype->id_match) |
| 1721 | return ptype->id_match(ptype, skb->sk); |
| 1722 | else if ((struct sock *)ptype->af_packet_priv == skb->sk) |
| 1723 | return true; |
| 1724 | |
| 1725 | return false; |
| 1726 | } |
| 1727 | |
| 1728 | /* |
| 1729 | * Support routine. Sends outgoing frames to any network |
| 1730 | * taps currently in use. |
| 1731 | */ |
| 1732 | |
| 1733 | static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) |
| 1734 | { |
| 1735 | struct packet_type *ptype; |
| 1736 | struct sk_buff *skb2 = NULL; |
| 1737 | struct packet_type *pt_prev = NULL; |
| 1738 | |
| 1739 | rcu_read_lock(); |
| 1740 | list_for_each_entry_rcu(ptype, &ptype_all, list) { |
| 1741 | /* Never send packets back to the socket |
| 1742 | * they originated from - MvS (miquels@drinkel.ow.org) |
| 1743 | */ |
| 1744 | if ((ptype->dev == dev || !ptype->dev) && |
| 1745 | (!skb_loop_sk(ptype, skb))) { |
| 1746 | if (pt_prev) { |
| 1747 | deliver_skb(skb2, pt_prev, skb->dev); |
| 1748 | pt_prev = ptype; |
| 1749 | continue; |
| 1750 | } |
| 1751 | |
| 1752 | skb2 = skb_clone(skb, GFP_ATOMIC); |
| 1753 | if (!skb2) |
| 1754 | break; |
| 1755 | |
| 1756 | net_timestamp_set(skb2); |
| 1757 | |
| 1758 | /* skb->nh should be correctly |
| 1759 | set by sender, so that the second statement is |
| 1760 | just protection against buggy protocols. |
| 1761 | */ |
| 1762 | skb_reset_mac_header(skb2); |
| 1763 | |
| 1764 | if (skb_network_header(skb2) < skb2->data || |
| 1765 | skb_network_header(skb2) > skb_tail_pointer(skb2)) { |
| 1766 | net_crit_ratelimited("protocol %04x is buggy, dev %s\n", |
| 1767 | ntohs(skb2->protocol), |
| 1768 | dev->name); |
| 1769 | skb_reset_network_header(skb2); |
| 1770 | } |
| 1771 | |
| 1772 | skb2->transport_header = skb2->network_header; |
| 1773 | skb2->pkt_type = PACKET_OUTGOING; |
| 1774 | pt_prev = ptype; |
| 1775 | } |
| 1776 | } |
| 1777 | if (pt_prev) |
| 1778 | pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); |
| 1779 | rcu_read_unlock(); |
| 1780 | } |
| 1781 | |
| 1782 | /** |
| 1783 | * netif_setup_tc - Handle tc mappings on real_num_tx_queues change |
| 1784 | * @dev: Network device |
| 1785 | * @txq: number of queues available |
| 1786 | * |
| 1787 | * If real_num_tx_queues is changed the tc mappings may no longer be |
| 1788 | * valid. To resolve this verify the tc mapping remains valid and if |
| 1789 | * not NULL the mapping. With no priorities mapping to this |
| 1790 | * offset/count pair it will no longer be used. In the worst case TC0 |
| 1791 | * is invalid nothing can be done so disable priority mappings. If is |
| 1792 | * expected that drivers will fix this mapping if they can before |
| 1793 | * calling netif_set_real_num_tx_queues. |
| 1794 | */ |
| 1795 | static void netif_setup_tc(struct net_device *dev, unsigned int txq) |
| 1796 | { |
| 1797 | int i; |
| 1798 | struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; |
| 1799 | |
| 1800 | /* If TC0 is invalidated disable TC mapping */ |
| 1801 | if (tc->offset + tc->count > txq) { |
| 1802 | pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); |
| 1803 | dev->num_tc = 0; |
| 1804 | return; |
| 1805 | } |
| 1806 | |
| 1807 | /* Invalidated prio to tc mappings set to TC0 */ |
| 1808 | for (i = 1; i < TC_BITMASK + 1; i++) { |
| 1809 | int q = netdev_get_prio_tc_map(dev, i); |
| 1810 | |
| 1811 | tc = &dev->tc_to_txq[q]; |
| 1812 | if (tc->offset + tc->count > txq) { |
| 1813 | pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n", |
| 1814 | i, q); |
| 1815 | netdev_set_prio_tc_map(dev, i, 0); |
| 1816 | } |
| 1817 | } |
| 1818 | } |
| 1819 | |
| 1820 | #ifdef CONFIG_XPS |
| 1821 | static DEFINE_MUTEX(xps_map_mutex); |
| 1822 | #define xmap_dereference(P) \ |
| 1823 | rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) |
| 1824 | |
| 1825 | static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps, |
| 1826 | int cpu, u16 index) |
| 1827 | { |
| 1828 | struct xps_map *map = NULL; |
| 1829 | int pos; |
| 1830 | |
| 1831 | if (dev_maps) |
| 1832 | map = xmap_dereference(dev_maps->cpu_map[cpu]); |
| 1833 | |
| 1834 | for (pos = 0; map && pos < map->len; pos++) { |
| 1835 | if (map->queues[pos] == index) { |
| 1836 | if (map->len > 1) { |
| 1837 | map->queues[pos] = map->queues[--map->len]; |
| 1838 | } else { |
| 1839 | RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL); |
| 1840 | kfree_rcu(map, rcu); |
| 1841 | map = NULL; |
| 1842 | } |
| 1843 | break; |
| 1844 | } |
| 1845 | } |
| 1846 | |
| 1847 | return map; |
| 1848 | } |
| 1849 | |
| 1850 | static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) |
| 1851 | { |
| 1852 | struct xps_dev_maps *dev_maps; |
| 1853 | int cpu, i; |
| 1854 | bool active = false; |
| 1855 | |
| 1856 | mutex_lock(&xps_map_mutex); |
| 1857 | dev_maps = xmap_dereference(dev->xps_maps); |
| 1858 | |
| 1859 | if (!dev_maps) |
| 1860 | goto out_no_maps; |
| 1861 | |
| 1862 | for_each_possible_cpu(cpu) { |
| 1863 | for (i = index; i < dev->num_tx_queues; i++) { |
| 1864 | if (!remove_xps_queue(dev_maps, cpu, i)) |
| 1865 | break; |
| 1866 | } |
| 1867 | if (i == dev->num_tx_queues) |
| 1868 | active = true; |
| 1869 | } |
| 1870 | |
| 1871 | if (!active) { |
| 1872 | RCU_INIT_POINTER(dev->xps_maps, NULL); |
| 1873 | kfree_rcu(dev_maps, rcu); |
| 1874 | } |
| 1875 | |
| 1876 | for (i = index; i < dev->num_tx_queues; i++) |
| 1877 | netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i), |
| 1878 | NUMA_NO_NODE); |
| 1879 | |
| 1880 | out_no_maps: |
| 1881 | mutex_unlock(&xps_map_mutex); |
| 1882 | } |
| 1883 | |
| 1884 | static struct xps_map *expand_xps_map(struct xps_map *map, |
| 1885 | int cpu, u16 index) |
| 1886 | { |
| 1887 | struct xps_map *new_map; |
| 1888 | int alloc_len = XPS_MIN_MAP_ALLOC; |
| 1889 | int i, pos; |
| 1890 | |
| 1891 | for (pos = 0; map && pos < map->len; pos++) { |
| 1892 | if (map->queues[pos] != index) |
| 1893 | continue; |
| 1894 | return map; |
| 1895 | } |
| 1896 | |
| 1897 | /* Need to add queue to this CPU's existing map */ |
| 1898 | if (map) { |
| 1899 | if (pos < map->alloc_len) |
| 1900 | return map; |
| 1901 | |
| 1902 | alloc_len = map->alloc_len * 2; |
| 1903 | } |
| 1904 | |
| 1905 | /* Need to allocate new map to store queue on this CPU's map */ |
| 1906 | new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, |
| 1907 | cpu_to_node(cpu)); |
| 1908 | if (!new_map) |
| 1909 | return NULL; |
| 1910 | |
| 1911 | for (i = 0; i < pos; i++) |
| 1912 | new_map->queues[i] = map->queues[i]; |
| 1913 | new_map->alloc_len = alloc_len; |
| 1914 | new_map->len = pos; |
| 1915 | |
| 1916 | return new_map; |
| 1917 | } |
| 1918 | |
| 1919 | int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, |
| 1920 | u16 index) |
| 1921 | { |
| 1922 | struct xps_dev_maps *dev_maps, *new_dev_maps = NULL; |
| 1923 | struct xps_map *map, *new_map; |
| 1924 | int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES); |
| 1925 | int cpu, numa_node_id = -2; |
| 1926 | bool active = false; |
| 1927 | |
| 1928 | mutex_lock(&xps_map_mutex); |
| 1929 | |
| 1930 | dev_maps = xmap_dereference(dev->xps_maps); |
| 1931 | |
| 1932 | /* allocate memory for queue storage */ |
| 1933 | for_each_online_cpu(cpu) { |
| 1934 | if (!cpumask_test_cpu(cpu, mask)) |
| 1935 | continue; |
| 1936 | |
| 1937 | if (!new_dev_maps) |
| 1938 | new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); |
| 1939 | if (!new_dev_maps) { |
| 1940 | mutex_unlock(&xps_map_mutex); |
| 1941 | return -ENOMEM; |
| 1942 | } |
| 1943 | |
| 1944 | map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) : |
| 1945 | NULL; |
| 1946 | |
| 1947 | map = expand_xps_map(map, cpu, index); |
| 1948 | if (!map) |
| 1949 | goto error; |
| 1950 | |
| 1951 | RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map); |
| 1952 | } |
| 1953 | |
| 1954 | if (!new_dev_maps) |
| 1955 | goto out_no_new_maps; |
| 1956 | |
| 1957 | for_each_possible_cpu(cpu) { |
| 1958 | if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) { |
| 1959 | /* add queue to CPU maps */ |
| 1960 | int pos = 0; |
| 1961 | |
| 1962 | map = xmap_dereference(new_dev_maps->cpu_map[cpu]); |
| 1963 | while ((pos < map->len) && (map->queues[pos] != index)) |
| 1964 | pos++; |
| 1965 | |
| 1966 | if (pos == map->len) |
| 1967 | map->queues[map->len++] = index; |
| 1968 | #ifdef CONFIG_NUMA |
| 1969 | if (numa_node_id == -2) |
| 1970 | numa_node_id = cpu_to_node(cpu); |
| 1971 | else if (numa_node_id != cpu_to_node(cpu)) |
| 1972 | numa_node_id = -1; |
| 1973 | #endif |
| 1974 | } else if (dev_maps) { |
| 1975 | /* fill in the new device map from the old device map */ |
| 1976 | map = xmap_dereference(dev_maps->cpu_map[cpu]); |
| 1977 | RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map); |
| 1978 | } |
| 1979 | |
| 1980 | } |
| 1981 | |
| 1982 | rcu_assign_pointer(dev->xps_maps, new_dev_maps); |
| 1983 | |
| 1984 | /* Cleanup old maps */ |
| 1985 | if (dev_maps) { |
| 1986 | for_each_possible_cpu(cpu) { |
| 1987 | new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]); |
| 1988 | map = xmap_dereference(dev_maps->cpu_map[cpu]); |
| 1989 | if (map && map != new_map) |
| 1990 | kfree_rcu(map, rcu); |
| 1991 | } |
| 1992 | |
| 1993 | kfree_rcu(dev_maps, rcu); |
| 1994 | } |
| 1995 | |
| 1996 | dev_maps = new_dev_maps; |
| 1997 | active = true; |
| 1998 | |
| 1999 | out_no_new_maps: |
| 2000 | /* update Tx queue numa node */ |
| 2001 | netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), |
| 2002 | (numa_node_id >= 0) ? numa_node_id : |
| 2003 | NUMA_NO_NODE); |
| 2004 | |
| 2005 | if (!dev_maps) |
| 2006 | goto out_no_maps; |
| 2007 | |
| 2008 | /* removes queue from unused CPUs */ |
| 2009 | for_each_possible_cpu(cpu) { |
| 2010 | if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) |
| 2011 | continue; |
| 2012 | |
| 2013 | if (remove_xps_queue(dev_maps, cpu, index)) |
| 2014 | active = true; |
| 2015 | } |
| 2016 | |
| 2017 | /* free map if not active */ |
| 2018 | if (!active) { |
| 2019 | RCU_INIT_POINTER(dev->xps_maps, NULL); |
| 2020 | kfree_rcu(dev_maps, rcu); |
| 2021 | } |
| 2022 | |
| 2023 | out_no_maps: |
| 2024 | mutex_unlock(&xps_map_mutex); |
| 2025 | |
| 2026 | return 0; |
| 2027 | error: |
| 2028 | /* remove any maps that we added */ |
| 2029 | for_each_possible_cpu(cpu) { |
| 2030 | new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]); |
| 2031 | map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) : |
| 2032 | NULL; |
| 2033 | if (new_map && new_map != map) |
| 2034 | kfree(new_map); |
| 2035 | } |
| 2036 | |
| 2037 | mutex_unlock(&xps_map_mutex); |
| 2038 | |
| 2039 | kfree(new_dev_maps); |
| 2040 | return -ENOMEM; |
| 2041 | } |
| 2042 | EXPORT_SYMBOL(netif_set_xps_queue); |
| 2043 | |
| 2044 | #endif |
| 2045 | /* |
| 2046 | * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues |
| 2047 | * greater then real_num_tx_queues stale skbs on the qdisc must be flushed. |
| 2048 | */ |
| 2049 | int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) |
| 2050 | { |
| 2051 | int rc; |
| 2052 | |
| 2053 | if (txq < 1 || txq > dev->num_tx_queues) |
| 2054 | return -EINVAL; |
| 2055 | |
| 2056 | if (dev->reg_state == NETREG_REGISTERED || |
| 2057 | dev->reg_state == NETREG_UNREGISTERING) { |
| 2058 | ASSERT_RTNL(); |
| 2059 | |
| 2060 | rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, |
| 2061 | txq); |
| 2062 | if (rc) |
| 2063 | return rc; |
| 2064 | |
| 2065 | if (dev->num_tc) |
| 2066 | netif_setup_tc(dev, txq); |
| 2067 | |
| 2068 | if (txq < dev->real_num_tx_queues) { |
| 2069 | qdisc_reset_all_tx_gt(dev, txq); |
| 2070 | #ifdef CONFIG_XPS |
| 2071 | netif_reset_xps_queues_gt(dev, txq); |
| 2072 | #endif |
| 2073 | } |
| 2074 | } |
| 2075 | |
| 2076 | dev->real_num_tx_queues = txq; |
| 2077 | return 0; |
| 2078 | } |
| 2079 | EXPORT_SYMBOL(netif_set_real_num_tx_queues); |
| 2080 | |
| 2081 | #ifdef CONFIG_RPS |
| 2082 | /** |
| 2083 | * netif_set_real_num_rx_queues - set actual number of RX queues used |
| 2084 | * @dev: Network device |
| 2085 | * @rxq: Actual number of RX queues |
| 2086 | * |
| 2087 | * This must be called either with the rtnl_lock held or before |
| 2088 | * registration of the net device. Returns 0 on success, or a |
| 2089 | * negative error code. If called before registration, it always |
| 2090 | * succeeds. |
| 2091 | */ |
| 2092 | int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) |
| 2093 | { |
| 2094 | int rc; |
| 2095 | |
| 2096 | if (rxq < 1 || rxq > dev->num_rx_queues) |
| 2097 | return -EINVAL; |
| 2098 | |
| 2099 | if (dev->reg_state == NETREG_REGISTERED) { |
| 2100 | ASSERT_RTNL(); |
| 2101 | |
| 2102 | rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, |
| 2103 | rxq); |
| 2104 | if (rc) |
| 2105 | return rc; |
| 2106 | } |
| 2107 | |
| 2108 | dev->real_num_rx_queues = rxq; |
| 2109 | return 0; |
| 2110 | } |
| 2111 | EXPORT_SYMBOL(netif_set_real_num_rx_queues); |
| 2112 | #endif |
| 2113 | |
| 2114 | /** |
| 2115 | * netif_get_num_default_rss_queues - default number of RSS queues |
| 2116 | * |
| 2117 | * This routine should set an upper limit on the number of RSS queues |
| 2118 | * used by default by multiqueue devices. |
| 2119 | */ |
| 2120 | int netif_get_num_default_rss_queues(void) |
| 2121 | { |
| 2122 | return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus()); |
| 2123 | } |
| 2124 | EXPORT_SYMBOL(netif_get_num_default_rss_queues); |
| 2125 | |
| 2126 | static inline void __netif_reschedule(struct Qdisc *q) |
| 2127 | { |
| 2128 | struct softnet_data *sd; |
| 2129 | unsigned long flags; |
| 2130 | |
| 2131 | local_irq_save(flags); |
| 2132 | sd = &__get_cpu_var(softnet_data); |
| 2133 | q->next_sched = NULL; |
| 2134 | *sd->output_queue_tailp = q; |
| 2135 | sd->output_queue_tailp = &q->next_sched; |
| 2136 | raise_softirq_irqoff(NET_TX_SOFTIRQ); |
| 2137 | local_irq_restore(flags); |
| 2138 | } |
| 2139 | |
| 2140 | void __netif_schedule(struct Qdisc *q) |
| 2141 | { |
| 2142 | if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) |
| 2143 | __netif_reschedule(q); |
| 2144 | } |
| 2145 | EXPORT_SYMBOL(__netif_schedule); |
| 2146 | |
| 2147 | struct dev_kfree_skb_cb { |
| 2148 | enum skb_free_reason reason; |
| 2149 | }; |
| 2150 | |
| 2151 | static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) |
| 2152 | { |
| 2153 | return (struct dev_kfree_skb_cb *)skb->cb; |
| 2154 | } |
| 2155 | |
| 2156 | void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) |
| 2157 | { |
| 2158 | unsigned long flags; |
| 2159 | |
| 2160 | if (likely(atomic_read(&skb->users) == 1)) { |
| 2161 | smp_rmb(); |
| 2162 | atomic_set(&skb->users, 0); |
| 2163 | } else if (likely(!atomic_dec_and_test(&skb->users))) { |
| 2164 | return; |
| 2165 | } |
| 2166 | get_kfree_skb_cb(skb)->reason = reason; |
| 2167 | local_irq_save(flags); |
| 2168 | skb->next = __this_cpu_read(softnet_data.completion_queue); |
| 2169 | __this_cpu_write(softnet_data.completion_queue, skb); |
| 2170 | raise_softirq_irqoff(NET_TX_SOFTIRQ); |
| 2171 | local_irq_restore(flags); |
| 2172 | } |
| 2173 | EXPORT_SYMBOL(__dev_kfree_skb_irq); |
| 2174 | |
| 2175 | void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason) |
| 2176 | { |
| 2177 | if (in_irq() || irqs_disabled()) |
| 2178 | __dev_kfree_skb_irq(skb, reason); |
| 2179 | else |
| 2180 | dev_kfree_skb(skb); |
| 2181 | } |
| 2182 | EXPORT_SYMBOL(__dev_kfree_skb_any); |
| 2183 | |
| 2184 | |
| 2185 | /** |
| 2186 | * netif_device_detach - mark device as removed |
| 2187 | * @dev: network device |
| 2188 | * |
| 2189 | * Mark device as removed from system and therefore no longer available. |
| 2190 | */ |
| 2191 | void netif_device_detach(struct net_device *dev) |
| 2192 | { |
| 2193 | if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && |
| 2194 | netif_running(dev)) { |
| 2195 | netif_tx_stop_all_queues(dev); |
| 2196 | } |
| 2197 | } |
| 2198 | EXPORT_SYMBOL(netif_device_detach); |
| 2199 | |
| 2200 | /** |
| 2201 | * netif_device_attach - mark device as attached |
| 2202 | * @dev: network device |
| 2203 | * |
| 2204 | * Mark device as attached from system and restart if needed. |
| 2205 | */ |
| 2206 | void netif_device_attach(struct net_device *dev) |
| 2207 | { |
| 2208 | if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && |
| 2209 | netif_running(dev)) { |
| 2210 | netif_tx_wake_all_queues(dev); |
| 2211 | __netdev_watchdog_up(dev); |
| 2212 | } |
| 2213 | } |
| 2214 | EXPORT_SYMBOL(netif_device_attach); |
| 2215 | |
| 2216 | static void skb_warn_bad_offload(const struct sk_buff *skb) |
| 2217 | { |
| 2218 | static const netdev_features_t null_features = 0; |
| 2219 | struct net_device *dev = skb->dev; |
| 2220 | const char *driver = ""; |
| 2221 | |
| 2222 | if (!net_ratelimit()) |
| 2223 | return; |
| 2224 | |
| 2225 | if (dev && dev->dev.parent) |
| 2226 | driver = dev_driver_string(dev->dev.parent); |
| 2227 | |
| 2228 | WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d " |
| 2229 | "gso_type=%d ip_summed=%d\n", |
| 2230 | driver, dev ? &dev->features : &null_features, |
| 2231 | skb->sk ? &skb->sk->sk_route_caps : &null_features, |
| 2232 | skb->len, skb->data_len, skb_shinfo(skb)->gso_size, |
| 2233 | skb_shinfo(skb)->gso_type, skb->ip_summed); |
| 2234 | } |
| 2235 | |
| 2236 | /* |
| 2237 | * Invalidate hardware checksum when packet is to be mangled, and |
| 2238 | * complete checksum manually on outgoing path. |
| 2239 | */ |
| 2240 | int skb_checksum_help(struct sk_buff *skb) |
| 2241 | { |
| 2242 | __wsum csum; |
| 2243 | int ret = 0, offset; |
| 2244 | |
| 2245 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
| 2246 | goto out_set_summed; |
| 2247 | |
| 2248 | if (unlikely(skb_shinfo(skb)->gso_size)) { |
| 2249 | skb_warn_bad_offload(skb); |
| 2250 | return -EINVAL; |
| 2251 | } |
| 2252 | |
| 2253 | /* Before computing a checksum, we should make sure no frag could |
| 2254 | * be modified by an external entity : checksum could be wrong. |
| 2255 | */ |
| 2256 | if (skb_has_shared_frag(skb)) { |
| 2257 | ret = __skb_linearize(skb); |
| 2258 | if (ret) |
| 2259 | goto out; |
| 2260 | } |
| 2261 | |
| 2262 | offset = skb_checksum_start_offset(skb); |
| 2263 | BUG_ON(offset >= skb_headlen(skb)); |
| 2264 | csum = skb_checksum(skb, offset, skb->len - offset, 0); |
| 2265 | |
| 2266 | offset += skb->csum_offset; |
| 2267 | BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); |
| 2268 | |
| 2269 | if (skb_cloned(skb) && |
| 2270 | !skb_clone_writable(skb, offset + sizeof(__sum16))) { |
| 2271 | ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); |
| 2272 | if (ret) |
| 2273 | goto out; |
| 2274 | } |
| 2275 | |
| 2276 | *(__sum16 *)(skb->data + offset) = csum_fold(csum); |
| 2277 | out_set_summed: |
| 2278 | skb->ip_summed = CHECKSUM_NONE; |
| 2279 | out: |
| 2280 | return ret; |
| 2281 | } |
| 2282 | EXPORT_SYMBOL(skb_checksum_help); |
| 2283 | |
| 2284 | __be16 skb_network_protocol(struct sk_buff *skb) |
| 2285 | { |
| 2286 | __be16 type = skb->protocol; |
| 2287 | int vlan_depth = ETH_HLEN; |
| 2288 | |
| 2289 | /* Tunnel gso handlers can set protocol to ethernet. */ |
| 2290 | if (type == htons(ETH_P_TEB)) { |
| 2291 | struct ethhdr *eth; |
| 2292 | |
| 2293 | if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) |
| 2294 | return 0; |
| 2295 | |
| 2296 | eth = (struct ethhdr *)skb_mac_header(skb); |
| 2297 | type = eth->h_proto; |
| 2298 | } |
| 2299 | |
| 2300 | while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) { |
| 2301 | struct vlan_hdr *vh; |
| 2302 | |
| 2303 | if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN))) |
| 2304 | return 0; |
| 2305 | |
| 2306 | vh = (struct vlan_hdr *)(skb->data + vlan_depth); |
| 2307 | type = vh->h_vlan_encapsulated_proto; |
| 2308 | vlan_depth += VLAN_HLEN; |
| 2309 | } |
| 2310 | |
| 2311 | return type; |
| 2312 | } |
| 2313 | |
| 2314 | /** |
| 2315 | * skb_mac_gso_segment - mac layer segmentation handler. |
| 2316 | * @skb: buffer to segment |
| 2317 | * @features: features for the output path (see dev->features) |
| 2318 | */ |
| 2319 | struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb, |
| 2320 | netdev_features_t features) |
| 2321 | { |
| 2322 | struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); |
| 2323 | struct packet_offload *ptype; |
| 2324 | __be16 type = skb_network_protocol(skb); |
| 2325 | |
| 2326 | if (unlikely(!type)) |
| 2327 | return ERR_PTR(-EINVAL); |
| 2328 | |
| 2329 | __skb_pull(skb, skb->mac_len); |
| 2330 | |
| 2331 | rcu_read_lock(); |
| 2332 | list_for_each_entry_rcu(ptype, &offload_base, list) { |
| 2333 | if (ptype->type == type && ptype->callbacks.gso_segment) { |
| 2334 | if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { |
| 2335 | int err; |
| 2336 | |
| 2337 | err = ptype->callbacks.gso_send_check(skb); |
| 2338 | segs = ERR_PTR(err); |
| 2339 | if (err || skb_gso_ok(skb, features)) |
| 2340 | break; |
| 2341 | __skb_push(skb, (skb->data - |
| 2342 | skb_network_header(skb))); |
| 2343 | } |
| 2344 | segs = ptype->callbacks.gso_segment(skb, features); |
| 2345 | break; |
| 2346 | } |
| 2347 | } |
| 2348 | rcu_read_unlock(); |
| 2349 | |
| 2350 | __skb_push(skb, skb->data - skb_mac_header(skb)); |
| 2351 | |
| 2352 | return segs; |
| 2353 | } |
| 2354 | EXPORT_SYMBOL(skb_mac_gso_segment); |
| 2355 | |
| 2356 | |
| 2357 | /* openvswitch calls this on rx path, so we need a different check. |
| 2358 | */ |
| 2359 | static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) |
| 2360 | { |
| 2361 | if (tx_path) |
| 2362 | return skb->ip_summed != CHECKSUM_PARTIAL; |
| 2363 | else |
| 2364 | return skb->ip_summed == CHECKSUM_NONE; |
| 2365 | } |
| 2366 | |
| 2367 | /** |
| 2368 | * __skb_gso_segment - Perform segmentation on skb. |
| 2369 | * @skb: buffer to segment |
| 2370 | * @features: features for the output path (see dev->features) |
| 2371 | * @tx_path: whether it is called in TX path |
| 2372 | * |
| 2373 | * This function segments the given skb and returns a list of segments. |
| 2374 | * |
| 2375 | * It may return NULL if the skb requires no segmentation. This is |
| 2376 | * only possible when GSO is used for verifying header integrity. |
| 2377 | */ |
| 2378 | struct sk_buff *__skb_gso_segment(struct sk_buff *skb, |
| 2379 | netdev_features_t features, bool tx_path) |
| 2380 | { |
| 2381 | if (unlikely(skb_needs_check(skb, tx_path))) { |
| 2382 | int err; |
| 2383 | |
| 2384 | skb_warn_bad_offload(skb); |
| 2385 | |
| 2386 | if (skb_header_cloned(skb) && |
| 2387 | (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) |
| 2388 | return ERR_PTR(err); |
| 2389 | } |
| 2390 | |
| 2391 | SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); |
| 2392 | SKB_GSO_CB(skb)->encap_level = 0; |
| 2393 | |
| 2394 | skb_reset_mac_header(skb); |
| 2395 | skb_reset_mac_len(skb); |
| 2396 | |
| 2397 | return skb_mac_gso_segment(skb, features); |
| 2398 | } |
| 2399 | EXPORT_SYMBOL(__skb_gso_segment); |
| 2400 | |
| 2401 | /* Take action when hardware reception checksum errors are detected. */ |
| 2402 | #ifdef CONFIG_BUG |
| 2403 | void netdev_rx_csum_fault(struct net_device *dev) |
| 2404 | { |
| 2405 | if (net_ratelimit()) { |
| 2406 | pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>"); |
| 2407 | dump_stack(); |
| 2408 | } |
| 2409 | } |
| 2410 | EXPORT_SYMBOL(netdev_rx_csum_fault); |
| 2411 | #endif |
| 2412 | |
| 2413 | /* Actually, we should eliminate this check as soon as we know, that: |
| 2414 | * 1. IOMMU is present and allows to map all the memory. |
| 2415 | * 2. No high memory really exists on this machine. |
| 2416 | */ |
| 2417 | |
| 2418 | static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) |
| 2419 | { |
| 2420 | #ifdef CONFIG_HIGHMEM |
| 2421 | int i; |
| 2422 | if (!(dev->features & NETIF_F_HIGHDMA)) { |
| 2423 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 2424 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 2425 | if (PageHighMem(skb_frag_page(frag))) |
| 2426 | return 1; |
| 2427 | } |
| 2428 | } |
| 2429 | |
| 2430 | if (PCI_DMA_BUS_IS_PHYS) { |
| 2431 | struct device *pdev = dev->dev.parent; |
| 2432 | |
| 2433 | if (!pdev) |
| 2434 | return 0; |
| 2435 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 2436 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 2437 | dma_addr_t addr = page_to_phys(skb_frag_page(frag)); |
| 2438 | if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask) |
| 2439 | return 1; |
| 2440 | } |
| 2441 | } |
| 2442 | #endif |
| 2443 | return 0; |
| 2444 | } |
| 2445 | |
| 2446 | struct dev_gso_cb { |
| 2447 | void (*destructor)(struct sk_buff *skb); |
| 2448 | }; |
| 2449 | |
| 2450 | #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) |
| 2451 | |
| 2452 | static void dev_gso_skb_destructor(struct sk_buff *skb) |
| 2453 | { |
| 2454 | struct dev_gso_cb *cb; |
| 2455 | |
| 2456 | kfree_skb_list(skb->next); |
| 2457 | skb->next = NULL; |
| 2458 | |
| 2459 | cb = DEV_GSO_CB(skb); |
| 2460 | if (cb->destructor) |
| 2461 | cb->destructor(skb); |
| 2462 | } |
| 2463 | |
| 2464 | /** |
| 2465 | * dev_gso_segment - Perform emulated hardware segmentation on skb. |
| 2466 | * @skb: buffer to segment |
| 2467 | * @features: device features as applicable to this skb |
| 2468 | * |
| 2469 | * This function segments the given skb and stores the list of segments |
| 2470 | * in skb->next. |
| 2471 | */ |
| 2472 | static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features) |
| 2473 | { |
| 2474 | struct sk_buff *segs; |
| 2475 | |
| 2476 | segs = skb_gso_segment(skb, features); |
| 2477 | |
| 2478 | /* Verifying header integrity only. */ |
| 2479 | if (!segs) |
| 2480 | return 0; |
| 2481 | |
| 2482 | if (IS_ERR(segs)) |
| 2483 | return PTR_ERR(segs); |
| 2484 | |
| 2485 | skb->next = segs; |
| 2486 | DEV_GSO_CB(skb)->destructor = skb->destructor; |
| 2487 | skb->destructor = dev_gso_skb_destructor; |
| 2488 | |
| 2489 | return 0; |
| 2490 | } |
| 2491 | |
| 2492 | static netdev_features_t harmonize_features(struct sk_buff *skb, |
| 2493 | netdev_features_t features) |
| 2494 | { |
| 2495 | if (skb->ip_summed != CHECKSUM_NONE && |
| 2496 | !can_checksum_protocol(features, skb_network_protocol(skb))) { |
| 2497 | features &= ~NETIF_F_ALL_CSUM; |
| 2498 | } else if (illegal_highdma(skb->dev, skb)) { |
| 2499 | features &= ~NETIF_F_SG; |
| 2500 | } |
| 2501 | |
| 2502 | return features; |
| 2503 | } |
| 2504 | |
| 2505 | netdev_features_t netif_skb_features(struct sk_buff *skb) |
| 2506 | { |
| 2507 | __be16 protocol = skb->protocol; |
| 2508 | netdev_features_t features = skb->dev->features; |
| 2509 | |
| 2510 | if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs) |
| 2511 | features &= ~NETIF_F_GSO_MASK; |
| 2512 | |
| 2513 | if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) { |
| 2514 | struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; |
| 2515 | protocol = veh->h_vlan_encapsulated_proto; |
| 2516 | } else if (!vlan_tx_tag_present(skb)) { |
| 2517 | return harmonize_features(skb, features); |
| 2518 | } |
| 2519 | |
| 2520 | features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX | |
| 2521 | NETIF_F_HW_VLAN_STAG_TX); |
| 2522 | |
| 2523 | if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) |
| 2524 | features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | |
| 2525 | NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX | |
| 2526 | NETIF_F_HW_VLAN_STAG_TX; |
| 2527 | |
| 2528 | return harmonize_features(skb, features); |
| 2529 | } |
| 2530 | EXPORT_SYMBOL(netif_skb_features); |
| 2531 | |
| 2532 | int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, |
| 2533 | struct netdev_queue *txq) |
| 2534 | { |
| 2535 | const struct net_device_ops *ops = dev->netdev_ops; |
| 2536 | int rc = NETDEV_TX_OK; |
| 2537 | unsigned int skb_len; |
| 2538 | |
| 2539 | if (likely(!skb->next)) { |
| 2540 | netdev_features_t features; |
| 2541 | |
| 2542 | /* |
| 2543 | * If device doesn't need skb->dst, release it right now while |
| 2544 | * its hot in this cpu cache |
| 2545 | */ |
| 2546 | if (dev->priv_flags & IFF_XMIT_DST_RELEASE) |
| 2547 | skb_dst_drop(skb); |
| 2548 | |
| 2549 | features = netif_skb_features(skb); |
| 2550 | |
| 2551 | if (vlan_tx_tag_present(skb) && |
| 2552 | !vlan_hw_offload_capable(features, skb->vlan_proto)) { |
| 2553 | skb = __vlan_put_tag(skb, skb->vlan_proto, |
| 2554 | vlan_tx_tag_get(skb)); |
| 2555 | if (unlikely(!skb)) |
| 2556 | goto out; |
| 2557 | |
| 2558 | skb->vlan_tci = 0; |
| 2559 | } |
| 2560 | |
| 2561 | /* If encapsulation offload request, verify we are testing |
| 2562 | * hardware encapsulation features instead of standard |
| 2563 | * features for the netdev |
| 2564 | */ |
| 2565 | if (skb->encapsulation) |
| 2566 | features &= dev->hw_enc_features; |
| 2567 | |
| 2568 | if (netif_needs_gso(skb, features)) { |
| 2569 | if (unlikely(dev_gso_segment(skb, features))) |
| 2570 | goto out_kfree_skb; |
| 2571 | if (skb->next) |
| 2572 | goto gso; |
| 2573 | } else { |
| 2574 | if (skb_needs_linearize(skb, features) && |
| 2575 | __skb_linearize(skb)) |
| 2576 | goto out_kfree_skb; |
| 2577 | |
| 2578 | /* If packet is not checksummed and device does not |
| 2579 | * support checksumming for this protocol, complete |
| 2580 | * checksumming here. |
| 2581 | */ |
| 2582 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
| 2583 | if (skb->encapsulation) |
| 2584 | skb_set_inner_transport_header(skb, |
| 2585 | skb_checksum_start_offset(skb)); |
| 2586 | else |
| 2587 | skb_set_transport_header(skb, |
| 2588 | skb_checksum_start_offset(skb)); |
| 2589 | if (!(features & NETIF_F_ALL_CSUM) && |
| 2590 | skb_checksum_help(skb)) |
| 2591 | goto out_kfree_skb; |
| 2592 | } |
| 2593 | } |
| 2594 | |
| 2595 | if (!list_empty(&ptype_all)) |
| 2596 | dev_queue_xmit_nit(skb, dev); |
| 2597 | |
| 2598 | skb_len = skb->len; |
| 2599 | trace_net_dev_start_xmit(skb, dev); |
| 2600 | rc = ops->ndo_start_xmit(skb, dev); |
| 2601 | trace_net_dev_xmit(skb, rc, dev, skb_len); |
| 2602 | if (rc == NETDEV_TX_OK) |
| 2603 | txq_trans_update(txq); |
| 2604 | return rc; |
| 2605 | } |
| 2606 | |
| 2607 | gso: |
| 2608 | do { |
| 2609 | struct sk_buff *nskb = skb->next; |
| 2610 | |
| 2611 | skb->next = nskb->next; |
| 2612 | nskb->next = NULL; |
| 2613 | |
| 2614 | if (!list_empty(&ptype_all)) |
| 2615 | dev_queue_xmit_nit(nskb, dev); |
| 2616 | |
| 2617 | skb_len = nskb->len; |
| 2618 | trace_net_dev_start_xmit(nskb, dev); |
| 2619 | rc = ops->ndo_start_xmit(nskb, dev); |
| 2620 | trace_net_dev_xmit(nskb, rc, dev, skb_len); |
| 2621 | if (unlikely(rc != NETDEV_TX_OK)) { |
| 2622 | if (rc & ~NETDEV_TX_MASK) |
| 2623 | goto out_kfree_gso_skb; |
| 2624 | nskb->next = skb->next; |
| 2625 | skb->next = nskb; |
| 2626 | return rc; |
| 2627 | } |
| 2628 | txq_trans_update(txq); |
| 2629 | if (unlikely(netif_xmit_stopped(txq) && skb->next)) |
| 2630 | return NETDEV_TX_BUSY; |
| 2631 | } while (skb->next); |
| 2632 | |
| 2633 | out_kfree_gso_skb: |
| 2634 | if (likely(skb->next == NULL)) { |
| 2635 | skb->destructor = DEV_GSO_CB(skb)->destructor; |
| 2636 | consume_skb(skb); |
| 2637 | return rc; |
| 2638 | } |
| 2639 | out_kfree_skb: |
| 2640 | kfree_skb(skb); |
| 2641 | out: |
| 2642 | return rc; |
| 2643 | } |
| 2644 | EXPORT_SYMBOL_GPL(dev_hard_start_xmit); |
| 2645 | |
| 2646 | static void qdisc_pkt_len_init(struct sk_buff *skb) |
| 2647 | { |
| 2648 | const struct skb_shared_info *shinfo = skb_shinfo(skb); |
| 2649 | |
| 2650 | qdisc_skb_cb(skb)->pkt_len = skb->len; |
| 2651 | |
| 2652 | /* To get more precise estimation of bytes sent on wire, |
| 2653 | * we add to pkt_len the headers size of all segments |
| 2654 | */ |
| 2655 | if (shinfo->gso_size) { |
| 2656 | unsigned int hdr_len; |
| 2657 | u16 gso_segs = shinfo->gso_segs; |
| 2658 | |
| 2659 | /* mac layer + network layer */ |
| 2660 | hdr_len = skb_transport_header(skb) - skb_mac_header(skb); |
| 2661 | |
| 2662 | /* + transport layer */ |
| 2663 | if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) |
| 2664 | hdr_len += tcp_hdrlen(skb); |
| 2665 | else |
| 2666 | hdr_len += sizeof(struct udphdr); |
| 2667 | |
| 2668 | if (shinfo->gso_type & SKB_GSO_DODGY) |
| 2669 | gso_segs = DIV_ROUND_UP(skb->len - hdr_len, |
| 2670 | shinfo->gso_size); |
| 2671 | |
| 2672 | qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; |
| 2673 | } |
| 2674 | } |
| 2675 | |
| 2676 | static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, |
| 2677 | struct net_device *dev, |
| 2678 | struct netdev_queue *txq) |
| 2679 | { |
| 2680 | spinlock_t *root_lock = qdisc_lock(q); |
| 2681 | bool contended; |
| 2682 | int rc; |
| 2683 | |
| 2684 | qdisc_pkt_len_init(skb); |
| 2685 | qdisc_calculate_pkt_len(skb, q); |
| 2686 | /* |
| 2687 | * Heuristic to force contended enqueues to serialize on a |
| 2688 | * separate lock before trying to get qdisc main lock. |
| 2689 | * This permits __QDISC_STATE_RUNNING owner to get the lock more often |
| 2690 | * and dequeue packets faster. |
| 2691 | */ |
| 2692 | contended = qdisc_is_running(q); |
| 2693 | if (unlikely(contended)) |
| 2694 | spin_lock(&q->busylock); |
| 2695 | |
| 2696 | spin_lock(root_lock); |
| 2697 | if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { |
| 2698 | kfree_skb(skb); |
| 2699 | rc = NET_XMIT_DROP; |
| 2700 | } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && |
| 2701 | qdisc_run_begin(q)) { |
| 2702 | /* |
| 2703 | * This is a work-conserving queue; there are no old skbs |
| 2704 | * waiting to be sent out; and the qdisc is not running - |
| 2705 | * xmit the skb directly. |
| 2706 | */ |
| 2707 | if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE)) |
| 2708 | skb_dst_force(skb); |
| 2709 | |
| 2710 | qdisc_bstats_update(q, skb); |
| 2711 | |
| 2712 | if (sch_direct_xmit(skb, q, dev, txq, root_lock)) { |
| 2713 | if (unlikely(contended)) { |
| 2714 | spin_unlock(&q->busylock); |
| 2715 | contended = false; |
| 2716 | } |
| 2717 | __qdisc_run(q); |
| 2718 | } else |
| 2719 | qdisc_run_end(q); |
| 2720 | |
| 2721 | rc = NET_XMIT_SUCCESS; |
| 2722 | } else { |
| 2723 | skb_dst_force(skb); |
| 2724 | rc = q->enqueue(skb, q) & NET_XMIT_MASK; |
| 2725 | if (qdisc_run_begin(q)) { |
| 2726 | if (unlikely(contended)) { |
| 2727 | spin_unlock(&q->busylock); |
| 2728 | contended = false; |
| 2729 | } |
| 2730 | __qdisc_run(q); |
| 2731 | } |
| 2732 | } |
| 2733 | spin_unlock(root_lock); |
| 2734 | if (unlikely(contended)) |
| 2735 | spin_unlock(&q->busylock); |
| 2736 | return rc; |
| 2737 | } |
| 2738 | |
| 2739 | #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) |
| 2740 | static void skb_update_prio(struct sk_buff *skb) |
| 2741 | { |
| 2742 | struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap); |
| 2743 | |
| 2744 | if (!skb->priority && skb->sk && map) { |
| 2745 | unsigned int prioidx = skb->sk->sk_cgrp_prioidx; |
| 2746 | |
| 2747 | if (prioidx < map->priomap_len) |
| 2748 | skb->priority = map->priomap[prioidx]; |
| 2749 | } |
| 2750 | } |
| 2751 | #else |
| 2752 | #define skb_update_prio(skb) |
| 2753 | #endif |
| 2754 | |
| 2755 | static DEFINE_PER_CPU(int, xmit_recursion); |
| 2756 | #define RECURSION_LIMIT 10 |
| 2757 | |
| 2758 | /** |
| 2759 | * dev_loopback_xmit - loop back @skb |
| 2760 | * @skb: buffer to transmit |
| 2761 | */ |
| 2762 | int dev_loopback_xmit(struct sk_buff *skb) |
| 2763 | { |
| 2764 | skb_reset_mac_header(skb); |
| 2765 | __skb_pull(skb, skb_network_offset(skb)); |
| 2766 | skb->pkt_type = PACKET_LOOPBACK; |
| 2767 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 2768 | WARN_ON(!skb_dst(skb)); |
| 2769 | skb_dst_force(skb); |
| 2770 | netif_rx_ni(skb); |
| 2771 | return 0; |
| 2772 | } |
| 2773 | EXPORT_SYMBOL(dev_loopback_xmit); |
| 2774 | |
| 2775 | /** |
| 2776 | * dev_queue_xmit - transmit a buffer |
| 2777 | * @skb: buffer to transmit |
| 2778 | * |
| 2779 | * Queue a buffer for transmission to a network device. The caller must |
| 2780 | * have set the device and priority and built the buffer before calling |
| 2781 | * this function. The function can be called from an interrupt. |
| 2782 | * |
| 2783 | * A negative errno code is returned on a failure. A success does not |
| 2784 | * guarantee the frame will be transmitted as it may be dropped due |
| 2785 | * to congestion or traffic shaping. |
| 2786 | * |
| 2787 | * ----------------------------------------------------------------------------------- |
| 2788 | * I notice this method can also return errors from the queue disciplines, |
| 2789 | * including NET_XMIT_DROP, which is a positive value. So, errors can also |
| 2790 | * be positive. |
| 2791 | * |
| 2792 | * Regardless of the return value, the skb is consumed, so it is currently |
| 2793 | * difficult to retry a send to this method. (You can bump the ref count |
| 2794 | * before sending to hold a reference for retry if you are careful.) |
| 2795 | * |
| 2796 | * When calling this method, interrupts MUST be enabled. This is because |
| 2797 | * the BH enable code must have IRQs enabled so that it will not deadlock. |
| 2798 | * --BLG |
| 2799 | */ |
| 2800 | int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv) |
| 2801 | { |
| 2802 | struct net_device *dev = skb->dev; |
| 2803 | struct netdev_queue *txq; |
| 2804 | struct Qdisc *q; |
| 2805 | int rc = -ENOMEM; |
| 2806 | |
| 2807 | skb_reset_mac_header(skb); |
| 2808 | |
| 2809 | /* Disable soft irqs for various locks below. Also |
| 2810 | * stops preemption for RCU. |
| 2811 | */ |
| 2812 | rcu_read_lock_bh(); |
| 2813 | |
| 2814 | skb_update_prio(skb); |
| 2815 | |
| 2816 | txq = netdev_pick_tx(dev, skb, accel_priv); |
| 2817 | q = rcu_dereference_bh(txq->qdisc); |
| 2818 | |
| 2819 | #ifdef CONFIG_NET_CLS_ACT |
| 2820 | skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS); |
| 2821 | #endif |
| 2822 | trace_net_dev_queue(skb); |
| 2823 | if (q->enqueue) { |
| 2824 | rc = __dev_xmit_skb(skb, q, dev, txq); |
| 2825 | goto out; |
| 2826 | } |
| 2827 | |
| 2828 | /* The device has no queue. Common case for software devices: |
| 2829 | loopback, all the sorts of tunnels... |
| 2830 | |
| 2831 | Really, it is unlikely that netif_tx_lock protection is necessary |
| 2832 | here. (f.e. loopback and IP tunnels are clean ignoring statistics |
| 2833 | counters.) |
| 2834 | However, it is possible, that they rely on protection |
| 2835 | made by us here. |
| 2836 | |
| 2837 | Check this and shot the lock. It is not prone from deadlocks. |
| 2838 | Either shot noqueue qdisc, it is even simpler 8) |
| 2839 | */ |
| 2840 | if (dev->flags & IFF_UP) { |
| 2841 | int cpu = smp_processor_id(); /* ok because BHs are off */ |
| 2842 | |
| 2843 | if (txq->xmit_lock_owner != cpu) { |
| 2844 | |
| 2845 | if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT) |
| 2846 | goto recursion_alert; |
| 2847 | |
| 2848 | HARD_TX_LOCK(dev, txq, cpu); |
| 2849 | |
| 2850 | if (!netif_xmit_stopped(txq)) { |
| 2851 | __this_cpu_inc(xmit_recursion); |
| 2852 | rc = dev_hard_start_xmit(skb, dev, txq); |
| 2853 | __this_cpu_dec(xmit_recursion); |
| 2854 | if (dev_xmit_complete(rc)) { |
| 2855 | HARD_TX_UNLOCK(dev, txq); |
| 2856 | goto out; |
| 2857 | } |
| 2858 | } |
| 2859 | HARD_TX_UNLOCK(dev, txq); |
| 2860 | net_crit_ratelimited("Virtual device %s asks to queue packet!\n", |
| 2861 | dev->name); |
| 2862 | } else { |
| 2863 | /* Recursion is detected! It is possible, |
| 2864 | * unfortunately |
| 2865 | */ |
| 2866 | recursion_alert: |
| 2867 | net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", |
| 2868 | dev->name); |
| 2869 | } |
| 2870 | } |
| 2871 | |
| 2872 | rc = -ENETDOWN; |
| 2873 | rcu_read_unlock_bh(); |
| 2874 | |
| 2875 | kfree_skb(skb); |
| 2876 | return rc; |
| 2877 | out: |
| 2878 | rcu_read_unlock_bh(); |
| 2879 | return rc; |
| 2880 | } |
| 2881 | |
| 2882 | int dev_queue_xmit(struct sk_buff *skb) |
| 2883 | { |
| 2884 | return __dev_queue_xmit(skb, NULL); |
| 2885 | } |
| 2886 | EXPORT_SYMBOL(dev_queue_xmit); |
| 2887 | |
| 2888 | int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv) |
| 2889 | { |
| 2890 | return __dev_queue_xmit(skb, accel_priv); |
| 2891 | } |
| 2892 | EXPORT_SYMBOL(dev_queue_xmit_accel); |
| 2893 | |
| 2894 | |
| 2895 | /*======================================================================= |
| 2896 | Receiver routines |
| 2897 | =======================================================================*/ |
| 2898 | |
| 2899 | int netdev_max_backlog __read_mostly = 1000; |
| 2900 | EXPORT_SYMBOL(netdev_max_backlog); |
| 2901 | |
| 2902 | int netdev_tstamp_prequeue __read_mostly = 1; |
| 2903 | int netdev_budget __read_mostly = 300; |
| 2904 | int weight_p __read_mostly = 64; /* old backlog weight */ |
| 2905 | |
| 2906 | /* Called with irq disabled */ |
| 2907 | static inline void ____napi_schedule(struct softnet_data *sd, |
| 2908 | struct napi_struct *napi) |
| 2909 | { |
| 2910 | list_add_tail(&napi->poll_list, &sd->poll_list); |
| 2911 | __raise_softirq_irqoff(NET_RX_SOFTIRQ); |
| 2912 | } |
| 2913 | |
| 2914 | #ifdef CONFIG_RPS |
| 2915 | |
| 2916 | /* One global table that all flow-based protocols share. */ |
| 2917 | struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; |
| 2918 | EXPORT_SYMBOL(rps_sock_flow_table); |
| 2919 | |
| 2920 | struct static_key rps_needed __read_mostly; |
| 2921 | |
| 2922 | static struct rps_dev_flow * |
| 2923 | set_rps_cpu(struct net_device *dev, struct sk_buff *skb, |
| 2924 | struct rps_dev_flow *rflow, u16 next_cpu) |
| 2925 | { |
| 2926 | if (next_cpu != RPS_NO_CPU) { |
| 2927 | #ifdef CONFIG_RFS_ACCEL |
| 2928 | struct netdev_rx_queue *rxqueue; |
| 2929 | struct rps_dev_flow_table *flow_table; |
| 2930 | struct rps_dev_flow *old_rflow; |
| 2931 | u32 flow_id; |
| 2932 | u16 rxq_index; |
| 2933 | int rc; |
| 2934 | |
| 2935 | /* Should we steer this flow to a different hardware queue? */ |
| 2936 | if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || |
| 2937 | !(dev->features & NETIF_F_NTUPLE)) |
| 2938 | goto out; |
| 2939 | rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); |
| 2940 | if (rxq_index == skb_get_rx_queue(skb)) |
| 2941 | goto out; |
| 2942 | |
| 2943 | rxqueue = dev->_rx + rxq_index; |
| 2944 | flow_table = rcu_dereference(rxqueue->rps_flow_table); |
| 2945 | if (!flow_table) |
| 2946 | goto out; |
| 2947 | flow_id = skb->rxhash & flow_table->mask; |
| 2948 | rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, |
| 2949 | rxq_index, flow_id); |
| 2950 | if (rc < 0) |
| 2951 | goto out; |
| 2952 | old_rflow = rflow; |
| 2953 | rflow = &flow_table->flows[flow_id]; |
| 2954 | rflow->filter = rc; |
| 2955 | if (old_rflow->filter == rflow->filter) |
| 2956 | old_rflow->filter = RPS_NO_FILTER; |
| 2957 | out: |
| 2958 | #endif |
| 2959 | rflow->last_qtail = |
| 2960 | per_cpu(softnet_data, next_cpu).input_queue_head; |
| 2961 | } |
| 2962 | |
| 2963 | rflow->cpu = next_cpu; |
| 2964 | return rflow; |
| 2965 | } |
| 2966 | |
| 2967 | /* |
| 2968 | * get_rps_cpu is called from netif_receive_skb and returns the target |
| 2969 | * CPU from the RPS map of the receiving queue for a given skb. |
| 2970 | * rcu_read_lock must be held on entry. |
| 2971 | */ |
| 2972 | static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, |
| 2973 | struct rps_dev_flow **rflowp) |
| 2974 | { |
| 2975 | struct netdev_rx_queue *rxqueue; |
| 2976 | struct rps_map *map; |
| 2977 | struct rps_dev_flow_table *flow_table; |
| 2978 | struct rps_sock_flow_table *sock_flow_table; |
| 2979 | int cpu = -1; |
| 2980 | u16 tcpu; |
| 2981 | |
| 2982 | if (skb_rx_queue_recorded(skb)) { |
| 2983 | u16 index = skb_get_rx_queue(skb); |
| 2984 | if (unlikely(index >= dev->real_num_rx_queues)) { |
| 2985 | WARN_ONCE(dev->real_num_rx_queues > 1, |
| 2986 | "%s received packet on queue %u, but number " |
| 2987 | "of RX queues is %u\n", |
| 2988 | dev->name, index, dev->real_num_rx_queues); |
| 2989 | goto done; |
| 2990 | } |
| 2991 | rxqueue = dev->_rx + index; |
| 2992 | } else |
| 2993 | rxqueue = dev->_rx; |
| 2994 | |
| 2995 | map = rcu_dereference(rxqueue->rps_map); |
| 2996 | if (map) { |
| 2997 | if (map->len == 1 && |
| 2998 | !rcu_access_pointer(rxqueue->rps_flow_table)) { |
| 2999 | tcpu = map->cpus[0]; |
| 3000 | if (cpu_online(tcpu)) |
| 3001 | cpu = tcpu; |
| 3002 | goto done; |
| 3003 | } |
| 3004 | } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) { |
| 3005 | goto done; |
| 3006 | } |
| 3007 | |
| 3008 | skb_reset_network_header(skb); |
| 3009 | if (!skb_get_hash(skb)) |
| 3010 | goto done; |
| 3011 | |
| 3012 | flow_table = rcu_dereference(rxqueue->rps_flow_table); |
| 3013 | sock_flow_table = rcu_dereference(rps_sock_flow_table); |
| 3014 | if (flow_table && sock_flow_table) { |
| 3015 | u16 next_cpu; |
| 3016 | struct rps_dev_flow *rflow; |
| 3017 | |
| 3018 | rflow = &flow_table->flows[skb->rxhash & flow_table->mask]; |
| 3019 | tcpu = rflow->cpu; |
| 3020 | |
| 3021 | next_cpu = sock_flow_table->ents[skb->rxhash & |
| 3022 | sock_flow_table->mask]; |
| 3023 | |
| 3024 | /* |
| 3025 | * If the desired CPU (where last recvmsg was done) is |
| 3026 | * different from current CPU (one in the rx-queue flow |
| 3027 | * table entry), switch if one of the following holds: |
| 3028 | * - Current CPU is unset (equal to RPS_NO_CPU). |
| 3029 | * - Current CPU is offline. |
| 3030 | * - The current CPU's queue tail has advanced beyond the |
| 3031 | * last packet that was enqueued using this table entry. |
| 3032 | * This guarantees that all previous packets for the flow |
| 3033 | * have been dequeued, thus preserving in order delivery. |
| 3034 | */ |
| 3035 | if (unlikely(tcpu != next_cpu) && |
| 3036 | (tcpu == RPS_NO_CPU || !cpu_online(tcpu) || |
| 3037 | ((int)(per_cpu(softnet_data, tcpu).input_queue_head - |
| 3038 | rflow->last_qtail)) >= 0)) { |
| 3039 | tcpu = next_cpu; |
| 3040 | rflow = set_rps_cpu(dev, skb, rflow, next_cpu); |
| 3041 | } |
| 3042 | |
| 3043 | if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) { |
| 3044 | *rflowp = rflow; |
| 3045 | cpu = tcpu; |
| 3046 | goto done; |
| 3047 | } |
| 3048 | } |
| 3049 | |
| 3050 | if (map) { |
| 3051 | tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32]; |
| 3052 | |
| 3053 | if (cpu_online(tcpu)) { |
| 3054 | cpu = tcpu; |
| 3055 | goto done; |
| 3056 | } |
| 3057 | } |
| 3058 | |
| 3059 | done: |
| 3060 | return cpu; |
| 3061 | } |
| 3062 | |
| 3063 | #ifdef CONFIG_RFS_ACCEL |
| 3064 | |
| 3065 | /** |
| 3066 | * rps_may_expire_flow - check whether an RFS hardware filter may be removed |
| 3067 | * @dev: Device on which the filter was set |
| 3068 | * @rxq_index: RX queue index |
| 3069 | * @flow_id: Flow ID passed to ndo_rx_flow_steer() |
| 3070 | * @filter_id: Filter ID returned by ndo_rx_flow_steer() |
| 3071 | * |
| 3072 | * Drivers that implement ndo_rx_flow_steer() should periodically call |
| 3073 | * this function for each installed filter and remove the filters for |
| 3074 | * which it returns %true. |
| 3075 | */ |
| 3076 | bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, |
| 3077 | u32 flow_id, u16 filter_id) |
| 3078 | { |
| 3079 | struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; |
| 3080 | struct rps_dev_flow_table *flow_table; |
| 3081 | struct rps_dev_flow *rflow; |
| 3082 | bool expire = true; |
| 3083 | int cpu; |
| 3084 | |
| 3085 | rcu_read_lock(); |
| 3086 | flow_table = rcu_dereference(rxqueue->rps_flow_table); |
| 3087 | if (flow_table && flow_id <= flow_table->mask) { |
| 3088 | rflow = &flow_table->flows[flow_id]; |
| 3089 | cpu = ACCESS_ONCE(rflow->cpu); |
| 3090 | if (rflow->filter == filter_id && cpu != RPS_NO_CPU && |
| 3091 | ((int)(per_cpu(softnet_data, cpu).input_queue_head - |
| 3092 | rflow->last_qtail) < |
| 3093 | (int)(10 * flow_table->mask))) |
| 3094 | expire = false; |
| 3095 | } |
| 3096 | rcu_read_unlock(); |
| 3097 | return expire; |
| 3098 | } |
| 3099 | EXPORT_SYMBOL(rps_may_expire_flow); |
| 3100 | |
| 3101 | #endif /* CONFIG_RFS_ACCEL */ |
| 3102 | |
| 3103 | /* Called from hardirq (IPI) context */ |
| 3104 | static void rps_trigger_softirq(void *data) |
| 3105 | { |
| 3106 | struct softnet_data *sd = data; |
| 3107 | |
| 3108 | ____napi_schedule(sd, &sd->backlog); |
| 3109 | sd->received_rps++; |
| 3110 | } |
| 3111 | |
| 3112 | #endif /* CONFIG_RPS */ |
| 3113 | |
| 3114 | /* |
| 3115 | * Check if this softnet_data structure is another cpu one |
| 3116 | * If yes, queue it to our IPI list and return 1 |
| 3117 | * If no, return 0 |
| 3118 | */ |
| 3119 | static int rps_ipi_queued(struct softnet_data *sd) |
| 3120 | { |
| 3121 | #ifdef CONFIG_RPS |
| 3122 | struct softnet_data *mysd = &__get_cpu_var(softnet_data); |
| 3123 | |
| 3124 | if (sd != mysd) { |
| 3125 | sd->rps_ipi_next = mysd->rps_ipi_list; |
| 3126 | mysd->rps_ipi_list = sd; |
| 3127 | |
| 3128 | __raise_softirq_irqoff(NET_RX_SOFTIRQ); |
| 3129 | return 1; |
| 3130 | } |
| 3131 | #endif /* CONFIG_RPS */ |
| 3132 | return 0; |
| 3133 | } |
| 3134 | |
| 3135 | #ifdef CONFIG_NET_FLOW_LIMIT |
| 3136 | int netdev_flow_limit_table_len __read_mostly = (1 << 12); |
| 3137 | #endif |
| 3138 | |
| 3139 | static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) |
| 3140 | { |
| 3141 | #ifdef CONFIG_NET_FLOW_LIMIT |
| 3142 | struct sd_flow_limit *fl; |
| 3143 | struct softnet_data *sd; |
| 3144 | unsigned int old_flow, new_flow; |
| 3145 | |
| 3146 | if (qlen < (netdev_max_backlog >> 1)) |
| 3147 | return false; |
| 3148 | |
| 3149 | sd = &__get_cpu_var(softnet_data); |
| 3150 | |
| 3151 | rcu_read_lock(); |
| 3152 | fl = rcu_dereference(sd->flow_limit); |
| 3153 | if (fl) { |
| 3154 | new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); |
| 3155 | old_flow = fl->history[fl->history_head]; |
| 3156 | fl->history[fl->history_head] = new_flow; |
| 3157 | |
| 3158 | fl->history_head++; |
| 3159 | fl->history_head &= FLOW_LIMIT_HISTORY - 1; |
| 3160 | |
| 3161 | if (likely(fl->buckets[old_flow])) |
| 3162 | fl->buckets[old_flow]--; |
| 3163 | |
| 3164 | if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { |
| 3165 | fl->count++; |
| 3166 | rcu_read_unlock(); |
| 3167 | return true; |
| 3168 | } |
| 3169 | } |
| 3170 | rcu_read_unlock(); |
| 3171 | #endif |
| 3172 | return false; |
| 3173 | } |
| 3174 | |
| 3175 | /* |
| 3176 | * enqueue_to_backlog is called to queue an skb to a per CPU backlog |
| 3177 | * queue (may be a remote CPU queue). |
| 3178 | */ |
| 3179 | static int enqueue_to_backlog(struct sk_buff *skb, int cpu, |
| 3180 | unsigned int *qtail) |
| 3181 | { |
| 3182 | struct softnet_data *sd; |
| 3183 | unsigned long flags; |
| 3184 | unsigned int qlen; |
| 3185 | |
| 3186 | sd = &per_cpu(softnet_data, cpu); |
| 3187 | |
| 3188 | local_irq_save(flags); |
| 3189 | |
| 3190 | rps_lock(sd); |
| 3191 | qlen = skb_queue_len(&sd->input_pkt_queue); |
| 3192 | if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) { |
| 3193 | if (skb_queue_len(&sd->input_pkt_queue)) { |
| 3194 | enqueue: |
| 3195 | __skb_queue_tail(&sd->input_pkt_queue, skb); |
| 3196 | input_queue_tail_incr_save(sd, qtail); |
| 3197 | rps_unlock(sd); |
| 3198 | local_irq_restore(flags); |
| 3199 | return NET_RX_SUCCESS; |
| 3200 | } |
| 3201 | |
| 3202 | /* Schedule NAPI for backlog device |
| 3203 | * We can use non atomic operation since we own the queue lock |
| 3204 | */ |
| 3205 | if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { |
| 3206 | if (!rps_ipi_queued(sd)) |
| 3207 | ____napi_schedule(sd, &sd->backlog); |
| 3208 | } |
| 3209 | goto enqueue; |
| 3210 | } |
| 3211 | |
| 3212 | sd->dropped++; |
| 3213 | rps_unlock(sd); |
| 3214 | |
| 3215 | local_irq_restore(flags); |
| 3216 | |
| 3217 | atomic_long_inc(&skb->dev->rx_dropped); |
| 3218 | kfree_skb(skb); |
| 3219 | return NET_RX_DROP; |
| 3220 | } |
| 3221 | |
| 3222 | /** |
| 3223 | * netif_rx - post buffer to the network code |
| 3224 | * @skb: buffer to post |
| 3225 | * |
| 3226 | * This function receives a packet from a device driver and queues it for |
| 3227 | * the upper (protocol) levels to process. It always succeeds. The buffer |
| 3228 | * may be dropped during processing for congestion control or by the |
| 3229 | * protocol layers. |
| 3230 | * |
| 3231 | * return values: |
| 3232 | * NET_RX_SUCCESS (no congestion) |
| 3233 | * NET_RX_DROP (packet was dropped) |
| 3234 | * |
| 3235 | */ |
| 3236 | |
| 3237 | int netif_rx(struct sk_buff *skb) |
| 3238 | { |
| 3239 | int ret; |
| 3240 | |
| 3241 | /* if netpoll wants it, pretend we never saw it */ |
| 3242 | if (netpoll_rx(skb)) |
| 3243 | return NET_RX_DROP; |
| 3244 | |
| 3245 | net_timestamp_check(netdev_tstamp_prequeue, skb); |
| 3246 | |
| 3247 | trace_netif_rx(skb); |
| 3248 | #ifdef CONFIG_RPS |
| 3249 | if (static_key_false(&rps_needed)) { |
| 3250 | struct rps_dev_flow voidflow, *rflow = &voidflow; |
| 3251 | int cpu; |
| 3252 | |
| 3253 | preempt_disable(); |
| 3254 | rcu_read_lock(); |
| 3255 | |
| 3256 | cpu = get_rps_cpu(skb->dev, skb, &rflow); |
| 3257 | if (cpu < 0) |
| 3258 | cpu = smp_processor_id(); |
| 3259 | |
| 3260 | ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); |
| 3261 | |
| 3262 | rcu_read_unlock(); |
| 3263 | preempt_enable(); |
| 3264 | } else |
| 3265 | #endif |
| 3266 | { |
| 3267 | unsigned int qtail; |
| 3268 | ret = enqueue_to_backlog(skb, get_cpu(), &qtail); |
| 3269 | put_cpu(); |
| 3270 | } |
| 3271 | return ret; |
| 3272 | } |
| 3273 | EXPORT_SYMBOL(netif_rx); |
| 3274 | |
| 3275 | int netif_rx_ni(struct sk_buff *skb) |
| 3276 | { |
| 3277 | int err; |
| 3278 | |
| 3279 | preempt_disable(); |
| 3280 | err = netif_rx(skb); |
| 3281 | if (local_softirq_pending()) |
| 3282 | do_softirq(); |
| 3283 | preempt_enable(); |
| 3284 | |
| 3285 | return err; |
| 3286 | } |
| 3287 | EXPORT_SYMBOL(netif_rx_ni); |
| 3288 | |
| 3289 | static void net_tx_action(struct softirq_action *h) |
| 3290 | { |
| 3291 | struct softnet_data *sd = &__get_cpu_var(softnet_data); |
| 3292 | |
| 3293 | if (sd->completion_queue) { |
| 3294 | struct sk_buff *clist; |
| 3295 | |
| 3296 | local_irq_disable(); |
| 3297 | clist = sd->completion_queue; |
| 3298 | sd->completion_queue = NULL; |
| 3299 | local_irq_enable(); |
| 3300 | |
| 3301 | while (clist) { |
| 3302 | struct sk_buff *skb = clist; |
| 3303 | clist = clist->next; |
| 3304 | |
| 3305 | WARN_ON(atomic_read(&skb->users)); |
| 3306 | if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED)) |
| 3307 | trace_consume_skb(skb); |
| 3308 | else |
| 3309 | trace_kfree_skb(skb, net_tx_action); |
| 3310 | __kfree_skb(skb); |
| 3311 | } |
| 3312 | } |
| 3313 | |
| 3314 | if (sd->output_queue) { |
| 3315 | struct Qdisc *head; |
| 3316 | |
| 3317 | local_irq_disable(); |
| 3318 | head = sd->output_queue; |
| 3319 | sd->output_queue = NULL; |
| 3320 | sd->output_queue_tailp = &sd->output_queue; |
| 3321 | local_irq_enable(); |
| 3322 | |
| 3323 | while (head) { |
| 3324 | struct Qdisc *q = head; |
| 3325 | spinlock_t *root_lock; |
| 3326 | |
| 3327 | head = head->next_sched; |
| 3328 | |
| 3329 | root_lock = qdisc_lock(q); |
| 3330 | if (spin_trylock(root_lock)) { |
| 3331 | smp_mb__before_clear_bit(); |
| 3332 | clear_bit(__QDISC_STATE_SCHED, |
| 3333 | &q->state); |
| 3334 | qdisc_run(q); |
| 3335 | spin_unlock(root_lock); |
| 3336 | } else { |
| 3337 | if (!test_bit(__QDISC_STATE_DEACTIVATED, |
| 3338 | &q->state)) { |
| 3339 | __netif_reschedule(q); |
| 3340 | } else { |
| 3341 | smp_mb__before_clear_bit(); |
| 3342 | clear_bit(__QDISC_STATE_SCHED, |
| 3343 | &q->state); |
| 3344 | } |
| 3345 | } |
| 3346 | } |
| 3347 | } |
| 3348 | } |
| 3349 | |
| 3350 | #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \ |
| 3351 | (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)) |
| 3352 | /* This hook is defined here for ATM LANE */ |
| 3353 | int (*br_fdb_test_addr_hook)(struct net_device *dev, |
| 3354 | unsigned char *addr) __read_mostly; |
| 3355 | EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); |
| 3356 | #endif |
| 3357 | |
| 3358 | #ifdef CONFIG_NET_CLS_ACT |
| 3359 | /* TODO: Maybe we should just force sch_ingress to be compiled in |
| 3360 | * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions |
| 3361 | * a compare and 2 stores extra right now if we dont have it on |
| 3362 | * but have CONFIG_NET_CLS_ACT |
| 3363 | * NOTE: This doesn't stop any functionality; if you dont have |
| 3364 | * the ingress scheduler, you just can't add policies on ingress. |
| 3365 | * |
| 3366 | */ |
| 3367 | static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq) |
| 3368 | { |
| 3369 | struct net_device *dev = skb->dev; |
| 3370 | u32 ttl = G_TC_RTTL(skb->tc_verd); |
| 3371 | int result = TC_ACT_OK; |
| 3372 | struct Qdisc *q; |
| 3373 | |
| 3374 | if (unlikely(MAX_RED_LOOP < ttl++)) { |
| 3375 | net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n", |
| 3376 | skb->skb_iif, dev->ifindex); |
| 3377 | return TC_ACT_SHOT; |
| 3378 | } |
| 3379 | |
| 3380 | skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl); |
| 3381 | skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS); |
| 3382 | |
| 3383 | q = rxq->qdisc; |
| 3384 | if (q != &noop_qdisc) { |
| 3385 | spin_lock(qdisc_lock(q)); |
| 3386 | if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) |
| 3387 | result = qdisc_enqueue_root(skb, q); |
| 3388 | spin_unlock(qdisc_lock(q)); |
| 3389 | } |
| 3390 | |
| 3391 | return result; |
| 3392 | } |
| 3393 | |
| 3394 | static inline struct sk_buff *handle_ing(struct sk_buff *skb, |
| 3395 | struct packet_type **pt_prev, |
| 3396 | int *ret, struct net_device *orig_dev) |
| 3397 | { |
| 3398 | struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue); |
| 3399 | |
| 3400 | if (!rxq || rxq->qdisc == &noop_qdisc) |
| 3401 | goto out; |
| 3402 | |
| 3403 | if (*pt_prev) { |
| 3404 | *ret = deliver_skb(skb, *pt_prev, orig_dev); |
| 3405 | *pt_prev = NULL; |
| 3406 | } |
| 3407 | |
| 3408 | switch (ing_filter(skb, rxq)) { |
| 3409 | case TC_ACT_SHOT: |
| 3410 | case TC_ACT_STOLEN: |
| 3411 | kfree_skb(skb); |
| 3412 | return NULL; |
| 3413 | } |
| 3414 | |
| 3415 | out: |
| 3416 | skb->tc_verd = 0; |
| 3417 | return skb; |
| 3418 | } |
| 3419 | #endif |
| 3420 | |
| 3421 | /** |
| 3422 | * netdev_rx_handler_register - register receive handler |
| 3423 | * @dev: device to register a handler for |
| 3424 | * @rx_handler: receive handler to register |
| 3425 | * @rx_handler_data: data pointer that is used by rx handler |
| 3426 | * |
| 3427 | * Register a receive hander for a device. This handler will then be |
| 3428 | * called from __netif_receive_skb. A negative errno code is returned |
| 3429 | * on a failure. |
| 3430 | * |
| 3431 | * The caller must hold the rtnl_mutex. |
| 3432 | * |
| 3433 | * For a general description of rx_handler, see enum rx_handler_result. |
| 3434 | */ |
| 3435 | int netdev_rx_handler_register(struct net_device *dev, |
| 3436 | rx_handler_func_t *rx_handler, |
| 3437 | void *rx_handler_data) |
| 3438 | { |
| 3439 | ASSERT_RTNL(); |
| 3440 | |
| 3441 | if (dev->rx_handler) |
| 3442 | return -EBUSY; |
| 3443 | |
| 3444 | /* Note: rx_handler_data must be set before rx_handler */ |
| 3445 | rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); |
| 3446 | rcu_assign_pointer(dev->rx_handler, rx_handler); |
| 3447 | |
| 3448 | return 0; |
| 3449 | } |
| 3450 | EXPORT_SYMBOL_GPL(netdev_rx_handler_register); |
| 3451 | |
| 3452 | /** |
| 3453 | * netdev_rx_handler_unregister - unregister receive handler |
| 3454 | * @dev: device to unregister a handler from |
| 3455 | * |
| 3456 | * Unregister a receive handler from a device. |
| 3457 | * |
| 3458 | * The caller must hold the rtnl_mutex. |
| 3459 | */ |
| 3460 | void netdev_rx_handler_unregister(struct net_device *dev) |
| 3461 | { |
| 3462 | |
| 3463 | ASSERT_RTNL(); |
| 3464 | RCU_INIT_POINTER(dev->rx_handler, NULL); |
| 3465 | /* a reader seeing a non NULL rx_handler in a rcu_read_lock() |
| 3466 | * section has a guarantee to see a non NULL rx_handler_data |
| 3467 | * as well. |
| 3468 | */ |
| 3469 | synchronize_net(); |
| 3470 | RCU_INIT_POINTER(dev->rx_handler_data, NULL); |
| 3471 | } |
| 3472 | EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); |
| 3473 | |
| 3474 | /* |
| 3475 | * Limit the use of PFMEMALLOC reserves to those protocols that implement |
| 3476 | * the special handling of PFMEMALLOC skbs. |
| 3477 | */ |
| 3478 | static bool skb_pfmemalloc_protocol(struct sk_buff *skb) |
| 3479 | { |
| 3480 | switch (skb->protocol) { |
| 3481 | case __constant_htons(ETH_P_ARP): |
| 3482 | case __constant_htons(ETH_P_IP): |
| 3483 | case __constant_htons(ETH_P_IPV6): |
| 3484 | case __constant_htons(ETH_P_8021Q): |
| 3485 | case __constant_htons(ETH_P_8021AD): |
| 3486 | return true; |
| 3487 | default: |
| 3488 | return false; |
| 3489 | } |
| 3490 | } |
| 3491 | |
| 3492 | static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc) |
| 3493 | { |
| 3494 | struct packet_type *ptype, *pt_prev; |
| 3495 | rx_handler_func_t *rx_handler; |
| 3496 | struct net_device *orig_dev; |
| 3497 | struct net_device *null_or_dev; |
| 3498 | bool deliver_exact = false; |
| 3499 | int ret = NET_RX_DROP; |
| 3500 | __be16 type; |
| 3501 | |
| 3502 | net_timestamp_check(!netdev_tstamp_prequeue, skb); |
| 3503 | |
| 3504 | trace_netif_receive_skb(skb); |
| 3505 | |
| 3506 | /* if we've gotten here through NAPI, check netpoll */ |
| 3507 | if (netpoll_receive_skb(skb)) |
| 3508 | goto out; |
| 3509 | |
| 3510 | orig_dev = skb->dev; |
| 3511 | |
| 3512 | skb_reset_network_header(skb); |
| 3513 | if (!skb_transport_header_was_set(skb)) |
| 3514 | skb_reset_transport_header(skb); |
| 3515 | skb_reset_mac_len(skb); |
| 3516 | |
| 3517 | pt_prev = NULL; |
| 3518 | |
| 3519 | rcu_read_lock(); |
| 3520 | |
| 3521 | another_round: |
| 3522 | skb->skb_iif = skb->dev->ifindex; |
| 3523 | |
| 3524 | __this_cpu_inc(softnet_data.processed); |
| 3525 | |
| 3526 | if (skb->protocol == cpu_to_be16(ETH_P_8021Q) || |
| 3527 | skb->protocol == cpu_to_be16(ETH_P_8021AD)) { |
| 3528 | skb = vlan_untag(skb); |
| 3529 | if (unlikely(!skb)) |
| 3530 | goto unlock; |
| 3531 | } |
| 3532 | |
| 3533 | #ifdef CONFIG_NET_CLS_ACT |
| 3534 | if (skb->tc_verd & TC_NCLS) { |
| 3535 | skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); |
| 3536 | goto ncls; |
| 3537 | } |
| 3538 | #endif |
| 3539 | |
| 3540 | if (pfmemalloc) |
| 3541 | goto skip_taps; |
| 3542 | |
| 3543 | list_for_each_entry_rcu(ptype, &ptype_all, list) { |
| 3544 | if (!ptype->dev || ptype->dev == skb->dev) { |
| 3545 | if (pt_prev) |
| 3546 | ret = deliver_skb(skb, pt_prev, orig_dev); |
| 3547 | pt_prev = ptype; |
| 3548 | } |
| 3549 | } |
| 3550 | |
| 3551 | skip_taps: |
| 3552 | #ifdef CONFIG_NET_CLS_ACT |
| 3553 | skb = handle_ing(skb, &pt_prev, &ret, orig_dev); |
| 3554 | if (!skb) |
| 3555 | goto unlock; |
| 3556 | ncls: |
| 3557 | #endif |
| 3558 | |
| 3559 | if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) |
| 3560 | goto drop; |
| 3561 | |
| 3562 | if (vlan_tx_tag_present(skb)) { |
| 3563 | if (pt_prev) { |
| 3564 | ret = deliver_skb(skb, pt_prev, orig_dev); |
| 3565 | pt_prev = NULL; |
| 3566 | } |
| 3567 | if (vlan_do_receive(&skb)) |
| 3568 | goto another_round; |
| 3569 | else if (unlikely(!skb)) |
| 3570 | goto unlock; |
| 3571 | } |
| 3572 | |
| 3573 | rx_handler = rcu_dereference(skb->dev->rx_handler); |
| 3574 | if (rx_handler) { |
| 3575 | if (pt_prev) { |
| 3576 | ret = deliver_skb(skb, pt_prev, orig_dev); |
| 3577 | pt_prev = NULL; |
| 3578 | } |
| 3579 | switch (rx_handler(&skb)) { |
| 3580 | case RX_HANDLER_CONSUMED: |
| 3581 | ret = NET_RX_SUCCESS; |
| 3582 | goto unlock; |
| 3583 | case RX_HANDLER_ANOTHER: |
| 3584 | goto another_round; |
| 3585 | case RX_HANDLER_EXACT: |
| 3586 | deliver_exact = true; |
| 3587 | case RX_HANDLER_PASS: |
| 3588 | break; |
| 3589 | default: |
| 3590 | BUG(); |
| 3591 | } |
| 3592 | } |
| 3593 | |
| 3594 | if (unlikely(vlan_tx_tag_present(skb))) { |
| 3595 | if (vlan_tx_tag_get_id(skb)) |
| 3596 | skb->pkt_type = PACKET_OTHERHOST; |
| 3597 | /* Note: we might in the future use prio bits |
| 3598 | * and set skb->priority like in vlan_do_receive() |
| 3599 | * For the time being, just ignore Priority Code Point |
| 3600 | */ |
| 3601 | skb->vlan_tci = 0; |
| 3602 | } |
| 3603 | |
| 3604 | /* deliver only exact match when indicated */ |
| 3605 | null_or_dev = deliver_exact ? skb->dev : NULL; |
| 3606 | |
| 3607 | type = skb->protocol; |
| 3608 | list_for_each_entry_rcu(ptype, |
| 3609 | &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { |
| 3610 | if (ptype->type == type && |
| 3611 | (ptype->dev == null_or_dev || ptype->dev == skb->dev || |
| 3612 | ptype->dev == orig_dev)) { |
| 3613 | if (pt_prev) |
| 3614 | ret = deliver_skb(skb, pt_prev, orig_dev); |
| 3615 | pt_prev = ptype; |
| 3616 | } |
| 3617 | } |
| 3618 | |
| 3619 | if (pt_prev) { |
| 3620 | if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) |
| 3621 | goto drop; |
| 3622 | else |
| 3623 | ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); |
| 3624 | } else { |
| 3625 | drop: |
| 3626 | atomic_long_inc(&skb->dev->rx_dropped); |
| 3627 | kfree_skb(skb); |
| 3628 | /* Jamal, now you will not able to escape explaining |
| 3629 | * me how you were going to use this. :-) |
| 3630 | */ |
| 3631 | ret = NET_RX_DROP; |
| 3632 | } |
| 3633 | |
| 3634 | unlock: |
| 3635 | rcu_read_unlock(); |
| 3636 | out: |
| 3637 | return ret; |
| 3638 | } |
| 3639 | |
| 3640 | static int __netif_receive_skb(struct sk_buff *skb) |
| 3641 | { |
| 3642 | int ret; |
| 3643 | |
| 3644 | if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { |
| 3645 | unsigned long pflags = current->flags; |
| 3646 | |
| 3647 | /* |
| 3648 | * PFMEMALLOC skbs are special, they should |
| 3649 | * - be delivered to SOCK_MEMALLOC sockets only |
| 3650 | * - stay away from userspace |
| 3651 | * - have bounded memory usage |
| 3652 | * |
| 3653 | * Use PF_MEMALLOC as this saves us from propagating the allocation |
| 3654 | * context down to all allocation sites. |
| 3655 | */ |
| 3656 | current->flags |= PF_MEMALLOC; |
| 3657 | ret = __netif_receive_skb_core(skb, true); |
| 3658 | tsk_restore_flags(current, pflags, PF_MEMALLOC); |
| 3659 | } else |
| 3660 | ret = __netif_receive_skb_core(skb, false); |
| 3661 | |
| 3662 | return ret; |
| 3663 | } |
| 3664 | |
| 3665 | /** |
| 3666 | * netif_receive_skb - process receive buffer from network |
| 3667 | * @skb: buffer to process |
| 3668 | * |
| 3669 | * netif_receive_skb() is the main receive data processing function. |
| 3670 | * It always succeeds. The buffer may be dropped during processing |
| 3671 | * for congestion control or by the protocol layers. |
| 3672 | * |
| 3673 | * This function may only be called from softirq context and interrupts |
| 3674 | * should be enabled. |
| 3675 | * |
| 3676 | * Return values (usually ignored): |
| 3677 | * NET_RX_SUCCESS: no congestion |
| 3678 | * NET_RX_DROP: packet was dropped |
| 3679 | */ |
| 3680 | int netif_receive_skb(struct sk_buff *skb) |
| 3681 | { |
| 3682 | net_timestamp_check(netdev_tstamp_prequeue, skb); |
| 3683 | |
| 3684 | if (skb_defer_rx_timestamp(skb)) |
| 3685 | return NET_RX_SUCCESS; |
| 3686 | |
| 3687 | #ifdef CONFIG_RPS |
| 3688 | if (static_key_false(&rps_needed)) { |
| 3689 | struct rps_dev_flow voidflow, *rflow = &voidflow; |
| 3690 | int cpu, ret; |
| 3691 | |
| 3692 | rcu_read_lock(); |
| 3693 | |
| 3694 | cpu = get_rps_cpu(skb->dev, skb, &rflow); |
| 3695 | |
| 3696 | if (cpu >= 0) { |
| 3697 | ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); |
| 3698 | rcu_read_unlock(); |
| 3699 | return ret; |
| 3700 | } |
| 3701 | rcu_read_unlock(); |
| 3702 | } |
| 3703 | #endif |
| 3704 | return __netif_receive_skb(skb); |
| 3705 | } |
| 3706 | EXPORT_SYMBOL(netif_receive_skb); |
| 3707 | |
| 3708 | /* Network device is going away, flush any packets still pending |
| 3709 | * Called with irqs disabled. |
| 3710 | */ |
| 3711 | static void flush_backlog(void *arg) |
| 3712 | { |
| 3713 | struct net_device *dev = arg; |
| 3714 | struct softnet_data *sd = &__get_cpu_var(softnet_data); |
| 3715 | struct sk_buff *skb, *tmp; |
| 3716 | |
| 3717 | rps_lock(sd); |
| 3718 | skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { |
| 3719 | if (skb->dev == dev) { |
| 3720 | __skb_unlink(skb, &sd->input_pkt_queue); |
| 3721 | kfree_skb(skb); |
| 3722 | input_queue_head_incr(sd); |
| 3723 | } |
| 3724 | } |
| 3725 | rps_unlock(sd); |
| 3726 | |
| 3727 | skb_queue_walk_safe(&sd->process_queue, skb, tmp) { |
| 3728 | if (skb->dev == dev) { |
| 3729 | __skb_unlink(skb, &sd->process_queue); |
| 3730 | kfree_skb(skb); |
| 3731 | input_queue_head_incr(sd); |
| 3732 | } |
| 3733 | } |
| 3734 | } |
| 3735 | |
| 3736 | static int napi_gro_complete(struct sk_buff *skb) |
| 3737 | { |
| 3738 | struct packet_offload *ptype; |
| 3739 | __be16 type = skb->protocol; |
| 3740 | struct list_head *head = &offload_base; |
| 3741 | int err = -ENOENT; |
| 3742 | |
| 3743 | BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb)); |
| 3744 | |
| 3745 | if (NAPI_GRO_CB(skb)->count == 1) { |
| 3746 | skb_shinfo(skb)->gso_size = 0; |
| 3747 | goto out; |
| 3748 | } |
| 3749 | |
| 3750 | rcu_read_lock(); |
| 3751 | list_for_each_entry_rcu(ptype, head, list) { |
| 3752 | if (ptype->type != type || !ptype->callbacks.gro_complete) |
| 3753 | continue; |
| 3754 | |
| 3755 | err = ptype->callbacks.gro_complete(skb, 0); |
| 3756 | break; |
| 3757 | } |
| 3758 | rcu_read_unlock(); |
| 3759 | |
| 3760 | if (err) { |
| 3761 | WARN_ON(&ptype->list == head); |
| 3762 | kfree_skb(skb); |
| 3763 | return NET_RX_SUCCESS; |
| 3764 | } |
| 3765 | |
| 3766 | out: |
| 3767 | return netif_receive_skb(skb); |
| 3768 | } |
| 3769 | |
| 3770 | /* napi->gro_list contains packets ordered by age. |
| 3771 | * youngest packets at the head of it. |
| 3772 | * Complete skbs in reverse order to reduce latencies. |
| 3773 | */ |
| 3774 | void napi_gro_flush(struct napi_struct *napi, bool flush_old) |
| 3775 | { |
| 3776 | struct sk_buff *skb, *prev = NULL; |
| 3777 | |
| 3778 | /* scan list and build reverse chain */ |
| 3779 | for (skb = napi->gro_list; skb != NULL; skb = skb->next) { |
| 3780 | skb->prev = prev; |
| 3781 | prev = skb; |
| 3782 | } |
| 3783 | |
| 3784 | for (skb = prev; skb; skb = prev) { |
| 3785 | skb->next = NULL; |
| 3786 | |
| 3787 | if (flush_old && NAPI_GRO_CB(skb)->age == jiffies) |
| 3788 | return; |
| 3789 | |
| 3790 | prev = skb->prev; |
| 3791 | napi_gro_complete(skb); |
| 3792 | napi->gro_count--; |
| 3793 | } |
| 3794 | |
| 3795 | napi->gro_list = NULL; |
| 3796 | } |
| 3797 | EXPORT_SYMBOL(napi_gro_flush); |
| 3798 | |
| 3799 | static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb) |
| 3800 | { |
| 3801 | struct sk_buff *p; |
| 3802 | unsigned int maclen = skb->dev->hard_header_len; |
| 3803 | |
| 3804 | for (p = napi->gro_list; p; p = p->next) { |
| 3805 | unsigned long diffs; |
| 3806 | |
| 3807 | diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; |
| 3808 | diffs |= p->vlan_tci ^ skb->vlan_tci; |
| 3809 | if (maclen == ETH_HLEN) |
| 3810 | diffs |= compare_ether_header(skb_mac_header(p), |
| 3811 | skb_gro_mac_header(skb)); |
| 3812 | else if (!diffs) |
| 3813 | diffs = memcmp(skb_mac_header(p), |
| 3814 | skb_gro_mac_header(skb), |
| 3815 | maclen); |
| 3816 | NAPI_GRO_CB(p)->same_flow = !diffs; |
| 3817 | NAPI_GRO_CB(p)->flush = 0; |
| 3818 | } |
| 3819 | } |
| 3820 | |
| 3821 | static void skb_gro_reset_offset(struct sk_buff *skb) |
| 3822 | { |
| 3823 | const struct skb_shared_info *pinfo = skb_shinfo(skb); |
| 3824 | const skb_frag_t *frag0 = &pinfo->frags[0]; |
| 3825 | |
| 3826 | NAPI_GRO_CB(skb)->data_offset = 0; |
| 3827 | NAPI_GRO_CB(skb)->frag0 = NULL; |
| 3828 | NAPI_GRO_CB(skb)->frag0_len = 0; |
| 3829 | |
| 3830 | if (skb_mac_header(skb) == skb_tail_pointer(skb) && |
| 3831 | pinfo->nr_frags && |
| 3832 | !PageHighMem(skb_frag_page(frag0))) { |
| 3833 | NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0); |
| 3834 | NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0); |
| 3835 | } |
| 3836 | } |
| 3837 | |
| 3838 | static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) |
| 3839 | { |
| 3840 | struct sk_buff **pp = NULL; |
| 3841 | struct packet_offload *ptype; |
| 3842 | __be16 type = skb->protocol; |
| 3843 | struct list_head *head = &offload_base; |
| 3844 | int same_flow; |
| 3845 | enum gro_result ret; |
| 3846 | |
| 3847 | if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb)) |
| 3848 | goto normal; |
| 3849 | |
| 3850 | if (skb_is_gso(skb) || skb_has_frag_list(skb)) |
| 3851 | goto normal; |
| 3852 | |
| 3853 | skb_gro_reset_offset(skb); |
| 3854 | gro_list_prepare(napi, skb); |
| 3855 | NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */ |
| 3856 | |
| 3857 | rcu_read_lock(); |
| 3858 | list_for_each_entry_rcu(ptype, head, list) { |
| 3859 | if (ptype->type != type || !ptype->callbacks.gro_receive) |
| 3860 | continue; |
| 3861 | |
| 3862 | skb_set_network_header(skb, skb_gro_offset(skb)); |
| 3863 | skb_reset_mac_len(skb); |
| 3864 | NAPI_GRO_CB(skb)->same_flow = 0; |
| 3865 | NAPI_GRO_CB(skb)->flush = 0; |
| 3866 | NAPI_GRO_CB(skb)->free = 0; |
| 3867 | |
| 3868 | pp = ptype->callbacks.gro_receive(&napi->gro_list, skb); |
| 3869 | break; |
| 3870 | } |
| 3871 | rcu_read_unlock(); |
| 3872 | |
| 3873 | if (&ptype->list == head) |
| 3874 | goto normal; |
| 3875 | |
| 3876 | same_flow = NAPI_GRO_CB(skb)->same_flow; |
| 3877 | ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; |
| 3878 | |
| 3879 | if (pp) { |
| 3880 | struct sk_buff *nskb = *pp; |
| 3881 | |
| 3882 | *pp = nskb->next; |
| 3883 | nskb->next = NULL; |
| 3884 | napi_gro_complete(nskb); |
| 3885 | napi->gro_count--; |
| 3886 | } |
| 3887 | |
| 3888 | if (same_flow) |
| 3889 | goto ok; |
| 3890 | |
| 3891 | if (NAPI_GRO_CB(skb)->flush) |
| 3892 | goto normal; |
| 3893 | |
| 3894 | if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) { |
| 3895 | struct sk_buff *nskb = napi->gro_list; |
| 3896 | |
| 3897 | /* locate the end of the list to select the 'oldest' flow */ |
| 3898 | while (nskb->next) { |
| 3899 | pp = &nskb->next; |
| 3900 | nskb = *pp; |
| 3901 | } |
| 3902 | *pp = NULL; |
| 3903 | nskb->next = NULL; |
| 3904 | napi_gro_complete(nskb); |
| 3905 | } else { |
| 3906 | napi->gro_count++; |
| 3907 | } |
| 3908 | NAPI_GRO_CB(skb)->count = 1; |
| 3909 | NAPI_GRO_CB(skb)->age = jiffies; |
| 3910 | skb_shinfo(skb)->gso_size = skb_gro_len(skb); |
| 3911 | skb->next = napi->gro_list; |
| 3912 | napi->gro_list = skb; |
| 3913 | ret = GRO_HELD; |
| 3914 | |
| 3915 | pull: |
| 3916 | if (skb_headlen(skb) < skb_gro_offset(skb)) { |
| 3917 | int grow = skb_gro_offset(skb) - skb_headlen(skb); |
| 3918 | |
| 3919 | BUG_ON(skb->end - skb->tail < grow); |
| 3920 | |
| 3921 | memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); |
| 3922 | |
| 3923 | skb->tail += grow; |
| 3924 | skb->data_len -= grow; |
| 3925 | |
| 3926 | skb_shinfo(skb)->frags[0].page_offset += grow; |
| 3927 | skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow); |
| 3928 | |
| 3929 | if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) { |
| 3930 | skb_frag_unref(skb, 0); |
| 3931 | memmove(skb_shinfo(skb)->frags, |
| 3932 | skb_shinfo(skb)->frags + 1, |
| 3933 | --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t)); |
| 3934 | } |
| 3935 | } |
| 3936 | |
| 3937 | ok: |
| 3938 | return ret; |
| 3939 | |
| 3940 | normal: |
| 3941 | ret = GRO_NORMAL; |
| 3942 | goto pull; |
| 3943 | } |
| 3944 | |
| 3945 | struct packet_offload *gro_find_receive_by_type(__be16 type) |
| 3946 | { |
| 3947 | struct list_head *offload_head = &offload_base; |
| 3948 | struct packet_offload *ptype; |
| 3949 | |
| 3950 | list_for_each_entry_rcu(ptype, offload_head, list) { |
| 3951 | if (ptype->type != type || !ptype->callbacks.gro_receive) |
| 3952 | continue; |
| 3953 | return ptype; |
| 3954 | } |
| 3955 | return NULL; |
| 3956 | } |
| 3957 | |
| 3958 | struct packet_offload *gro_find_complete_by_type(__be16 type) |
| 3959 | { |
| 3960 | struct list_head *offload_head = &offload_base; |
| 3961 | struct packet_offload *ptype; |
| 3962 | |
| 3963 | list_for_each_entry_rcu(ptype, offload_head, list) { |
| 3964 | if (ptype->type != type || !ptype->callbacks.gro_complete) |
| 3965 | continue; |
| 3966 | return ptype; |
| 3967 | } |
| 3968 | return NULL; |
| 3969 | } |
| 3970 | |
| 3971 | static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) |
| 3972 | { |
| 3973 | switch (ret) { |
| 3974 | case GRO_NORMAL: |
| 3975 | if (netif_receive_skb(skb)) |
| 3976 | ret = GRO_DROP; |
| 3977 | break; |
| 3978 | |
| 3979 | case GRO_DROP: |
| 3980 | kfree_skb(skb); |
| 3981 | break; |
| 3982 | |
| 3983 | case GRO_MERGED_FREE: |
| 3984 | if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) |
| 3985 | kmem_cache_free(skbuff_head_cache, skb); |
| 3986 | else |
| 3987 | __kfree_skb(skb); |
| 3988 | break; |
| 3989 | |
| 3990 | case GRO_HELD: |
| 3991 | case GRO_MERGED: |
| 3992 | break; |
| 3993 | } |
| 3994 | |
| 3995 | return ret; |
| 3996 | } |
| 3997 | |
| 3998 | gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) |
| 3999 | { |
| 4000 | return napi_skb_finish(dev_gro_receive(napi, skb), skb); |
| 4001 | } |
| 4002 | EXPORT_SYMBOL(napi_gro_receive); |
| 4003 | |
| 4004 | static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) |
| 4005 | { |
| 4006 | __skb_pull(skb, skb_headlen(skb)); |
| 4007 | /* restore the reserve we had after netdev_alloc_skb_ip_align() */ |
| 4008 | skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb)); |
| 4009 | skb->vlan_tci = 0; |
| 4010 | skb->dev = napi->dev; |
| 4011 | skb->skb_iif = 0; |
| 4012 | |
| 4013 | napi->skb = skb; |
| 4014 | } |
| 4015 | |
| 4016 | struct sk_buff *napi_get_frags(struct napi_struct *napi) |
| 4017 | { |
| 4018 | struct sk_buff *skb = napi->skb; |
| 4019 | |
| 4020 | if (!skb) { |
| 4021 | skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD); |
| 4022 | napi->skb = skb; |
| 4023 | } |
| 4024 | return skb; |
| 4025 | } |
| 4026 | EXPORT_SYMBOL(napi_get_frags); |
| 4027 | |
| 4028 | static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, |
| 4029 | gro_result_t ret) |
| 4030 | { |
| 4031 | switch (ret) { |
| 4032 | case GRO_NORMAL: |
| 4033 | if (netif_receive_skb(skb)) |
| 4034 | ret = GRO_DROP; |
| 4035 | break; |
| 4036 | |
| 4037 | case GRO_DROP: |
| 4038 | case GRO_MERGED_FREE: |
| 4039 | napi_reuse_skb(napi, skb); |
| 4040 | break; |
| 4041 | |
| 4042 | case GRO_HELD: |
| 4043 | case GRO_MERGED: |
| 4044 | break; |
| 4045 | } |
| 4046 | |
| 4047 | return ret; |
| 4048 | } |
| 4049 | |
| 4050 | static struct sk_buff *napi_frags_skb(struct napi_struct *napi) |
| 4051 | { |
| 4052 | struct sk_buff *skb = napi->skb; |
| 4053 | |
| 4054 | napi->skb = NULL; |
| 4055 | |
| 4056 | if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) { |
| 4057 | napi_reuse_skb(napi, skb); |
| 4058 | return NULL; |
| 4059 | } |
| 4060 | skb->protocol = eth_type_trans(skb, skb->dev); |
| 4061 | |
| 4062 | return skb; |
| 4063 | } |
| 4064 | |
| 4065 | gro_result_t napi_gro_frags(struct napi_struct *napi) |
| 4066 | { |
| 4067 | struct sk_buff *skb = napi_frags_skb(napi); |
| 4068 | |
| 4069 | if (!skb) |
| 4070 | return GRO_DROP; |
| 4071 | |
| 4072 | return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb)); |
| 4073 | } |
| 4074 | EXPORT_SYMBOL(napi_gro_frags); |
| 4075 | |
| 4076 | /* |
| 4077 | * net_rps_action_and_irq_enable sends any pending IPI's for rps. |
| 4078 | * Note: called with local irq disabled, but exits with local irq enabled. |
| 4079 | */ |
| 4080 | static void net_rps_action_and_irq_enable(struct softnet_data *sd) |
| 4081 | { |
| 4082 | #ifdef CONFIG_RPS |
| 4083 | struct softnet_data *remsd = sd->rps_ipi_list; |
| 4084 | |
| 4085 | if (remsd) { |
| 4086 | sd->rps_ipi_list = NULL; |
| 4087 | |
| 4088 | local_irq_enable(); |
| 4089 | |
| 4090 | /* Send pending IPI's to kick RPS processing on remote cpus. */ |
| 4091 | while (remsd) { |
| 4092 | struct softnet_data *next = remsd->rps_ipi_next; |
| 4093 | |
| 4094 | if (cpu_online(remsd->cpu)) |
| 4095 | __smp_call_function_single(remsd->cpu, |
| 4096 | &remsd->csd, 0); |
| 4097 | remsd = next; |
| 4098 | } |
| 4099 | } else |
| 4100 | #endif |
| 4101 | local_irq_enable(); |
| 4102 | } |
| 4103 | |
| 4104 | static int process_backlog(struct napi_struct *napi, int quota) |
| 4105 | { |
| 4106 | int work = 0; |
| 4107 | struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); |
| 4108 | |
| 4109 | #ifdef CONFIG_RPS |
| 4110 | /* Check if we have pending ipi, its better to send them now, |
| 4111 | * not waiting net_rx_action() end. |
| 4112 | */ |
| 4113 | if (sd->rps_ipi_list) { |
| 4114 | local_irq_disable(); |
| 4115 | net_rps_action_and_irq_enable(sd); |
| 4116 | } |
| 4117 | #endif |
| 4118 | napi->weight = weight_p; |
| 4119 | local_irq_disable(); |
| 4120 | while (work < quota) { |
| 4121 | struct sk_buff *skb; |
| 4122 | unsigned int qlen; |
| 4123 | |
| 4124 | while ((skb = __skb_dequeue(&sd->process_queue))) { |
| 4125 | local_irq_enable(); |
| 4126 | __netif_receive_skb(skb); |
| 4127 | local_irq_disable(); |
| 4128 | input_queue_head_incr(sd); |
| 4129 | if (++work >= quota) { |
| 4130 | local_irq_enable(); |
| 4131 | return work; |
| 4132 | } |
| 4133 | } |
| 4134 | |
| 4135 | rps_lock(sd); |
| 4136 | qlen = skb_queue_len(&sd->input_pkt_queue); |
| 4137 | if (qlen) |
| 4138 | skb_queue_splice_tail_init(&sd->input_pkt_queue, |
| 4139 | &sd->process_queue); |
| 4140 | |
| 4141 | if (qlen < quota - work) { |
| 4142 | /* |
| 4143 | * Inline a custom version of __napi_complete(). |
| 4144 | * only current cpu owns and manipulates this napi, |
| 4145 | * and NAPI_STATE_SCHED is the only possible flag set on backlog. |
| 4146 | * we can use a plain write instead of clear_bit(), |
| 4147 | * and we dont need an smp_mb() memory barrier. |
| 4148 | */ |
| 4149 | list_del(&napi->poll_list); |
| 4150 | napi->state = 0; |
| 4151 | |
| 4152 | quota = work + qlen; |
| 4153 | } |
| 4154 | rps_unlock(sd); |
| 4155 | } |
| 4156 | local_irq_enable(); |
| 4157 | |
| 4158 | return work; |
| 4159 | } |
| 4160 | |
| 4161 | /** |
| 4162 | * __napi_schedule - schedule for receive |
| 4163 | * @n: entry to schedule |
| 4164 | * |
| 4165 | * The entry's receive function will be scheduled to run |
| 4166 | */ |
| 4167 | void __napi_schedule(struct napi_struct *n) |
| 4168 | { |
| 4169 | unsigned long flags; |
| 4170 | |
| 4171 | local_irq_save(flags); |
| 4172 | ____napi_schedule(&__get_cpu_var(softnet_data), n); |
| 4173 | local_irq_restore(flags); |
| 4174 | } |
| 4175 | EXPORT_SYMBOL(__napi_schedule); |
| 4176 | |
| 4177 | void __napi_complete(struct napi_struct *n) |
| 4178 | { |
| 4179 | BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); |
| 4180 | BUG_ON(n->gro_list); |
| 4181 | |
| 4182 | list_del(&n->poll_list); |
| 4183 | smp_mb__before_clear_bit(); |
| 4184 | clear_bit(NAPI_STATE_SCHED, &n->state); |
| 4185 | } |
| 4186 | EXPORT_SYMBOL(__napi_complete); |
| 4187 | |
| 4188 | void napi_complete(struct napi_struct *n) |
| 4189 | { |
| 4190 | unsigned long flags; |
| 4191 | |
| 4192 | /* |
| 4193 | * don't let napi dequeue from the cpu poll list |
| 4194 | * just in case its running on a different cpu |
| 4195 | */ |
| 4196 | if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state))) |
| 4197 | return; |
| 4198 | |
| 4199 | napi_gro_flush(n, false); |
| 4200 | local_irq_save(flags); |
| 4201 | __napi_complete(n); |
| 4202 | local_irq_restore(flags); |
| 4203 | } |
| 4204 | EXPORT_SYMBOL(napi_complete); |
| 4205 | |
| 4206 | /* must be called under rcu_read_lock(), as we dont take a reference */ |
| 4207 | struct napi_struct *napi_by_id(unsigned int napi_id) |
| 4208 | { |
| 4209 | unsigned int hash = napi_id % HASH_SIZE(napi_hash); |
| 4210 | struct napi_struct *napi; |
| 4211 | |
| 4212 | hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) |
| 4213 | if (napi->napi_id == napi_id) |
| 4214 | return napi; |
| 4215 | |
| 4216 | return NULL; |
| 4217 | } |
| 4218 | EXPORT_SYMBOL_GPL(napi_by_id); |
| 4219 | |
| 4220 | void napi_hash_add(struct napi_struct *napi) |
| 4221 | { |
| 4222 | if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) { |
| 4223 | |
| 4224 | spin_lock(&napi_hash_lock); |
| 4225 | |
| 4226 | /* 0 is not a valid id, we also skip an id that is taken |
| 4227 | * we expect both events to be extremely rare |
| 4228 | */ |
| 4229 | napi->napi_id = 0; |
| 4230 | while (!napi->napi_id) { |
| 4231 | napi->napi_id = ++napi_gen_id; |
| 4232 | if (napi_by_id(napi->napi_id)) |
| 4233 | napi->napi_id = 0; |
| 4234 | } |
| 4235 | |
| 4236 | hlist_add_head_rcu(&napi->napi_hash_node, |
| 4237 | &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); |
| 4238 | |
| 4239 | spin_unlock(&napi_hash_lock); |
| 4240 | } |
| 4241 | } |
| 4242 | EXPORT_SYMBOL_GPL(napi_hash_add); |
| 4243 | |
| 4244 | /* Warning : caller is responsible to make sure rcu grace period |
| 4245 | * is respected before freeing memory containing @napi |
| 4246 | */ |
| 4247 | void napi_hash_del(struct napi_struct *napi) |
| 4248 | { |
| 4249 | spin_lock(&napi_hash_lock); |
| 4250 | |
| 4251 | if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) |
| 4252 | hlist_del_rcu(&napi->napi_hash_node); |
| 4253 | |
| 4254 | spin_unlock(&napi_hash_lock); |
| 4255 | } |
| 4256 | EXPORT_SYMBOL_GPL(napi_hash_del); |
| 4257 | |
| 4258 | void netif_napi_add(struct net_device *dev, struct napi_struct *napi, |
| 4259 | int (*poll)(struct napi_struct *, int), int weight) |
| 4260 | { |
| 4261 | INIT_LIST_HEAD(&napi->poll_list); |
| 4262 | napi->gro_count = 0; |
| 4263 | napi->gro_list = NULL; |
| 4264 | napi->skb = NULL; |
| 4265 | napi->poll = poll; |
| 4266 | if (weight > NAPI_POLL_WEIGHT) |
| 4267 | pr_err_once("netif_napi_add() called with weight %d on device %s\n", |
| 4268 | weight, dev->name); |
| 4269 | napi->weight = weight; |
| 4270 | list_add(&napi->dev_list, &dev->napi_list); |
| 4271 | napi->dev = dev; |
| 4272 | #ifdef CONFIG_NETPOLL |
| 4273 | spin_lock_init(&napi->poll_lock); |
| 4274 | napi->poll_owner = -1; |
| 4275 | #endif |
| 4276 | set_bit(NAPI_STATE_SCHED, &napi->state); |
| 4277 | } |
| 4278 | EXPORT_SYMBOL(netif_napi_add); |
| 4279 | |
| 4280 | void netif_napi_del(struct napi_struct *napi) |
| 4281 | { |
| 4282 | list_del_init(&napi->dev_list); |
| 4283 | napi_free_frags(napi); |
| 4284 | |
| 4285 | kfree_skb_list(napi->gro_list); |
| 4286 | napi->gro_list = NULL; |
| 4287 | napi->gro_count = 0; |
| 4288 | } |
| 4289 | EXPORT_SYMBOL(netif_napi_del); |
| 4290 | |
| 4291 | static void net_rx_action(struct softirq_action *h) |
| 4292 | { |
| 4293 | struct softnet_data *sd = &__get_cpu_var(softnet_data); |
| 4294 | unsigned long time_limit = jiffies + 2; |
| 4295 | int budget = netdev_budget; |
| 4296 | void *have; |
| 4297 | |
| 4298 | local_irq_disable(); |
| 4299 | |
| 4300 | while (!list_empty(&sd->poll_list)) { |
| 4301 | struct napi_struct *n; |
| 4302 | int work, weight; |
| 4303 | |
| 4304 | /* If softirq window is exhuasted then punt. |
| 4305 | * Allow this to run for 2 jiffies since which will allow |
| 4306 | * an average latency of 1.5/HZ. |
| 4307 | */ |
| 4308 | if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit))) |
| 4309 | goto softnet_break; |
| 4310 | |
| 4311 | local_irq_enable(); |
| 4312 | |
| 4313 | /* Even though interrupts have been re-enabled, this |
| 4314 | * access is safe because interrupts can only add new |
| 4315 | * entries to the tail of this list, and only ->poll() |
| 4316 | * calls can remove this head entry from the list. |
| 4317 | */ |
| 4318 | n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list); |
| 4319 | |
| 4320 | have = netpoll_poll_lock(n); |
| 4321 | |
| 4322 | weight = n->weight; |
| 4323 | |
| 4324 | /* This NAPI_STATE_SCHED test is for avoiding a race |
| 4325 | * with netpoll's poll_napi(). Only the entity which |
| 4326 | * obtains the lock and sees NAPI_STATE_SCHED set will |
| 4327 | * actually make the ->poll() call. Therefore we avoid |
| 4328 | * accidentally calling ->poll() when NAPI is not scheduled. |
| 4329 | */ |
| 4330 | work = 0; |
| 4331 | if (test_bit(NAPI_STATE_SCHED, &n->state)) { |
| 4332 | work = n->poll(n, weight); |
| 4333 | trace_napi_poll(n); |
| 4334 | } |
| 4335 | |
| 4336 | WARN_ON_ONCE(work > weight); |
| 4337 | |
| 4338 | budget -= work; |
| 4339 | |
| 4340 | local_irq_disable(); |
| 4341 | |
| 4342 | /* Drivers must not modify the NAPI state if they |
| 4343 | * consume the entire weight. In such cases this code |
| 4344 | * still "owns" the NAPI instance and therefore can |
| 4345 | * move the instance around on the list at-will. |
| 4346 | */ |
| 4347 | if (unlikely(work == weight)) { |
| 4348 | if (unlikely(napi_disable_pending(n))) { |
| 4349 | local_irq_enable(); |
| 4350 | napi_complete(n); |
| 4351 | local_irq_disable(); |
| 4352 | } else { |
| 4353 | if (n->gro_list) { |
| 4354 | /* flush too old packets |
| 4355 | * If HZ < 1000, flush all packets. |
| 4356 | */ |
| 4357 | local_irq_enable(); |
| 4358 | napi_gro_flush(n, HZ >= 1000); |
| 4359 | local_irq_disable(); |
| 4360 | } |
| 4361 | list_move_tail(&n->poll_list, &sd->poll_list); |
| 4362 | } |
| 4363 | } |
| 4364 | |
| 4365 | netpoll_poll_unlock(have); |
| 4366 | } |
| 4367 | out: |
| 4368 | net_rps_action_and_irq_enable(sd); |
| 4369 | |
| 4370 | #ifdef CONFIG_NET_DMA |
| 4371 | /* |
| 4372 | * There may not be any more sk_buffs coming right now, so push |
| 4373 | * any pending DMA copies to hardware |
| 4374 | */ |
| 4375 | dma_issue_pending_all(); |
| 4376 | #endif |
| 4377 | |
| 4378 | return; |
| 4379 | |
| 4380 | softnet_break: |
| 4381 | sd->time_squeeze++; |
| 4382 | __raise_softirq_irqoff(NET_RX_SOFTIRQ); |
| 4383 | goto out; |
| 4384 | } |
| 4385 | |
| 4386 | struct netdev_adjacent { |
| 4387 | struct net_device *dev; |
| 4388 | |
| 4389 | /* upper master flag, there can only be one master device per list */ |
| 4390 | bool master; |
| 4391 | |
| 4392 | /* counter for the number of times this device was added to us */ |
| 4393 | u16 ref_nr; |
| 4394 | |
| 4395 | /* private field for the users */ |
| 4396 | void *private; |
| 4397 | |
| 4398 | struct list_head list; |
| 4399 | struct rcu_head rcu; |
| 4400 | }; |
| 4401 | |
| 4402 | static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev, |
| 4403 | struct net_device *adj_dev, |
| 4404 | struct list_head *adj_list) |
| 4405 | { |
| 4406 | struct netdev_adjacent *adj; |
| 4407 | |
| 4408 | list_for_each_entry(adj, adj_list, list) { |
| 4409 | if (adj->dev == adj_dev) |
| 4410 | return adj; |
| 4411 | } |
| 4412 | return NULL; |
| 4413 | } |
| 4414 | |
| 4415 | /** |
| 4416 | * netdev_has_upper_dev - Check if device is linked to an upper device |
| 4417 | * @dev: device |
| 4418 | * @upper_dev: upper device to check |
| 4419 | * |
| 4420 | * Find out if a device is linked to specified upper device and return true |
| 4421 | * in case it is. Note that this checks only immediate upper device, |
| 4422 | * not through a complete stack of devices. The caller must hold the RTNL lock. |
| 4423 | */ |
| 4424 | bool netdev_has_upper_dev(struct net_device *dev, |
| 4425 | struct net_device *upper_dev) |
| 4426 | { |
| 4427 | ASSERT_RTNL(); |
| 4428 | |
| 4429 | return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper); |
| 4430 | } |
| 4431 | EXPORT_SYMBOL(netdev_has_upper_dev); |
| 4432 | |
| 4433 | /** |
| 4434 | * netdev_has_any_upper_dev - Check if device is linked to some device |
| 4435 | * @dev: device |
| 4436 | * |
| 4437 | * Find out if a device is linked to an upper device and return true in case |
| 4438 | * it is. The caller must hold the RTNL lock. |
| 4439 | */ |
| 4440 | static bool netdev_has_any_upper_dev(struct net_device *dev) |
| 4441 | { |
| 4442 | ASSERT_RTNL(); |
| 4443 | |
| 4444 | return !list_empty(&dev->all_adj_list.upper); |
| 4445 | } |
| 4446 | |
| 4447 | /** |
| 4448 | * netdev_master_upper_dev_get - Get master upper device |
| 4449 | * @dev: device |
| 4450 | * |
| 4451 | * Find a master upper device and return pointer to it or NULL in case |
| 4452 | * it's not there. The caller must hold the RTNL lock. |
| 4453 | */ |
| 4454 | struct net_device *netdev_master_upper_dev_get(struct net_device *dev) |
| 4455 | { |
| 4456 | struct netdev_adjacent *upper; |
| 4457 | |
| 4458 | ASSERT_RTNL(); |
| 4459 | |
| 4460 | if (list_empty(&dev->adj_list.upper)) |
| 4461 | return NULL; |
| 4462 | |
| 4463 | upper = list_first_entry(&dev->adj_list.upper, |
| 4464 | struct netdev_adjacent, list); |
| 4465 | if (likely(upper->master)) |
| 4466 | return upper->dev; |
| 4467 | return NULL; |
| 4468 | } |
| 4469 | EXPORT_SYMBOL(netdev_master_upper_dev_get); |
| 4470 | |
| 4471 | void *netdev_adjacent_get_private(struct list_head *adj_list) |
| 4472 | { |
| 4473 | struct netdev_adjacent *adj; |
| 4474 | |
| 4475 | adj = list_entry(adj_list, struct netdev_adjacent, list); |
| 4476 | |
| 4477 | return adj->private; |
| 4478 | } |
| 4479 | EXPORT_SYMBOL(netdev_adjacent_get_private); |
| 4480 | |
| 4481 | /** |
| 4482 | * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list |
| 4483 | * @dev: device |
| 4484 | * @iter: list_head ** of the current position |
| 4485 | * |
| 4486 | * Gets the next device from the dev's upper list, starting from iter |
| 4487 | * position. The caller must hold RCU read lock. |
| 4488 | */ |
| 4489 | struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev, |
| 4490 | struct list_head **iter) |
| 4491 | { |
| 4492 | struct netdev_adjacent *upper; |
| 4493 | |
| 4494 | WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); |
| 4495 | |
| 4496 | upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); |
| 4497 | |
| 4498 | if (&upper->list == &dev->all_adj_list.upper) |
| 4499 | return NULL; |
| 4500 | |
| 4501 | *iter = &upper->list; |
| 4502 | |
| 4503 | return upper->dev; |
| 4504 | } |
| 4505 | EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu); |
| 4506 | |
| 4507 | /** |
| 4508 | * netdev_lower_get_next_private - Get the next ->private from the |
| 4509 | * lower neighbour list |
| 4510 | * @dev: device |
| 4511 | * @iter: list_head ** of the current position |
| 4512 | * |
| 4513 | * Gets the next netdev_adjacent->private from the dev's lower neighbour |
| 4514 | * list, starting from iter position. The caller must hold either hold the |
| 4515 | * RTNL lock or its own locking that guarantees that the neighbour lower |
| 4516 | * list will remain unchainged. |
| 4517 | */ |
| 4518 | void *netdev_lower_get_next_private(struct net_device *dev, |
| 4519 | struct list_head **iter) |
| 4520 | { |
| 4521 | struct netdev_adjacent *lower; |
| 4522 | |
| 4523 | lower = list_entry(*iter, struct netdev_adjacent, list); |
| 4524 | |
| 4525 | if (&lower->list == &dev->adj_list.lower) |
| 4526 | return NULL; |
| 4527 | |
| 4528 | if (iter) |
| 4529 | *iter = lower->list.next; |
| 4530 | |
| 4531 | return lower->private; |
| 4532 | } |
| 4533 | EXPORT_SYMBOL(netdev_lower_get_next_private); |
| 4534 | |
| 4535 | /** |
| 4536 | * netdev_lower_get_next_private_rcu - Get the next ->private from the |
| 4537 | * lower neighbour list, RCU |
| 4538 | * variant |
| 4539 | * @dev: device |
| 4540 | * @iter: list_head ** of the current position |
| 4541 | * |
| 4542 | * Gets the next netdev_adjacent->private from the dev's lower neighbour |
| 4543 | * list, starting from iter position. The caller must hold RCU read lock. |
| 4544 | */ |
| 4545 | void *netdev_lower_get_next_private_rcu(struct net_device *dev, |
| 4546 | struct list_head **iter) |
| 4547 | { |
| 4548 | struct netdev_adjacent *lower; |
| 4549 | |
| 4550 | WARN_ON_ONCE(!rcu_read_lock_held()); |
| 4551 | |
| 4552 | lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); |
| 4553 | |
| 4554 | if (&lower->list == &dev->adj_list.lower) |
| 4555 | return NULL; |
| 4556 | |
| 4557 | if (iter) |
| 4558 | *iter = &lower->list; |
| 4559 | |
| 4560 | return lower->private; |
| 4561 | } |
| 4562 | EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); |
| 4563 | |
| 4564 | /** |
| 4565 | * netdev_lower_get_first_private_rcu - Get the first ->private from the |
| 4566 | * lower neighbour list, RCU |
| 4567 | * variant |
| 4568 | * @dev: device |
| 4569 | * |
| 4570 | * Gets the first netdev_adjacent->private from the dev's lower neighbour |
| 4571 | * list. The caller must hold RCU read lock. |
| 4572 | */ |
| 4573 | void *netdev_lower_get_first_private_rcu(struct net_device *dev) |
| 4574 | { |
| 4575 | struct netdev_adjacent *lower; |
| 4576 | |
| 4577 | lower = list_first_or_null_rcu(&dev->adj_list.lower, |
| 4578 | struct netdev_adjacent, list); |
| 4579 | if (lower) |
| 4580 | return lower->private; |
| 4581 | return NULL; |
| 4582 | } |
| 4583 | EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); |
| 4584 | |
| 4585 | /** |
| 4586 | * netdev_master_upper_dev_get_rcu - Get master upper device |
| 4587 | * @dev: device |
| 4588 | * |
| 4589 | * Find a master upper device and return pointer to it or NULL in case |
| 4590 | * it's not there. The caller must hold the RCU read lock. |
| 4591 | */ |
| 4592 | struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) |
| 4593 | { |
| 4594 | struct netdev_adjacent *upper; |
| 4595 | |
| 4596 | upper = list_first_or_null_rcu(&dev->adj_list.upper, |
| 4597 | struct netdev_adjacent, list); |
| 4598 | if (upper && likely(upper->master)) |
| 4599 | return upper->dev; |
| 4600 | return NULL; |
| 4601 | } |
| 4602 | EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); |
| 4603 | |
| 4604 | static int __netdev_adjacent_dev_insert(struct net_device *dev, |
| 4605 | struct net_device *adj_dev, |
| 4606 | struct list_head *dev_list, |
| 4607 | void *private, bool master) |
| 4608 | { |
| 4609 | struct netdev_adjacent *adj; |
| 4610 | char linkname[IFNAMSIZ+7]; |
| 4611 | int ret; |
| 4612 | |
| 4613 | adj = __netdev_find_adj(dev, adj_dev, dev_list); |
| 4614 | |
| 4615 | if (adj) { |
| 4616 | adj->ref_nr++; |
| 4617 | return 0; |
| 4618 | } |
| 4619 | |
| 4620 | adj = kmalloc(sizeof(*adj), GFP_KERNEL); |
| 4621 | if (!adj) |
| 4622 | return -ENOMEM; |
| 4623 | |
| 4624 | adj->dev = adj_dev; |
| 4625 | adj->master = master; |
| 4626 | adj->ref_nr = 1; |
| 4627 | adj->private = private; |
| 4628 | dev_hold(adj_dev); |
| 4629 | |
| 4630 | pr_debug("dev_hold for %s, because of link added from %s to %s\n", |
| 4631 | adj_dev->name, dev->name, adj_dev->name); |
| 4632 | |
| 4633 | if (dev_list == &dev->adj_list.lower) { |
| 4634 | sprintf(linkname, "lower_%s", adj_dev->name); |
| 4635 | ret = sysfs_create_link(&(dev->dev.kobj), |
| 4636 | &(adj_dev->dev.kobj), linkname); |
| 4637 | if (ret) |
| 4638 | goto free_adj; |
| 4639 | } else if (dev_list == &dev->adj_list.upper) { |
| 4640 | sprintf(linkname, "upper_%s", adj_dev->name); |
| 4641 | ret = sysfs_create_link(&(dev->dev.kobj), |
| 4642 | &(adj_dev->dev.kobj), linkname); |
| 4643 | if (ret) |
| 4644 | goto free_adj; |
| 4645 | } |
| 4646 | |
| 4647 | /* Ensure that master link is always the first item in list. */ |
| 4648 | if (master) { |
| 4649 | ret = sysfs_create_link(&(dev->dev.kobj), |
| 4650 | &(adj_dev->dev.kobj), "master"); |
| 4651 | if (ret) |
| 4652 | goto remove_symlinks; |
| 4653 | |
| 4654 | list_add_rcu(&adj->list, dev_list); |
| 4655 | } else { |
| 4656 | list_add_tail_rcu(&adj->list, dev_list); |
| 4657 | } |
| 4658 | |
| 4659 | return 0; |
| 4660 | |
| 4661 | remove_symlinks: |
| 4662 | if (dev_list == &dev->adj_list.lower) { |
| 4663 | sprintf(linkname, "lower_%s", adj_dev->name); |
| 4664 | sysfs_remove_link(&(dev->dev.kobj), linkname); |
| 4665 | } else if (dev_list == &dev->adj_list.upper) { |
| 4666 | sprintf(linkname, "upper_%s", adj_dev->name); |
| 4667 | sysfs_remove_link(&(dev->dev.kobj), linkname); |
| 4668 | } |
| 4669 | |
| 4670 | free_adj: |
| 4671 | kfree(adj); |
| 4672 | dev_put(adj_dev); |
| 4673 | |
| 4674 | return ret; |
| 4675 | } |
| 4676 | |
| 4677 | static void __netdev_adjacent_dev_remove(struct net_device *dev, |
| 4678 | struct net_device *adj_dev, |
| 4679 | struct list_head *dev_list) |
| 4680 | { |
| 4681 | struct netdev_adjacent *adj; |
| 4682 | char linkname[IFNAMSIZ+7]; |
| 4683 | |
| 4684 | adj = __netdev_find_adj(dev, adj_dev, dev_list); |
| 4685 | |
| 4686 | if (!adj) { |
| 4687 | pr_err("tried to remove device %s from %s\n", |
| 4688 | dev->name, adj_dev->name); |
| 4689 | BUG(); |
| 4690 | } |
| 4691 | |
| 4692 | if (adj->ref_nr > 1) { |
| 4693 | pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name, |
| 4694 | adj->ref_nr-1); |
| 4695 | adj->ref_nr--; |
| 4696 | return; |
| 4697 | } |
| 4698 | |
| 4699 | if (adj->master) |
| 4700 | sysfs_remove_link(&(dev->dev.kobj), "master"); |
| 4701 | |
| 4702 | if (dev_list == &dev->adj_list.lower) { |
| 4703 | sprintf(linkname, "lower_%s", adj_dev->name); |
| 4704 | sysfs_remove_link(&(dev->dev.kobj), linkname); |
| 4705 | } else if (dev_list == &dev->adj_list.upper) { |
| 4706 | sprintf(linkname, "upper_%s", adj_dev->name); |
| 4707 | sysfs_remove_link(&(dev->dev.kobj), linkname); |
| 4708 | } |
| 4709 | |
| 4710 | list_del_rcu(&adj->list); |
| 4711 | pr_debug("dev_put for %s, because link removed from %s to %s\n", |
| 4712 | adj_dev->name, dev->name, adj_dev->name); |
| 4713 | dev_put(adj_dev); |
| 4714 | kfree_rcu(adj, rcu); |
| 4715 | } |
| 4716 | |
| 4717 | static int __netdev_adjacent_dev_link_lists(struct net_device *dev, |
| 4718 | struct net_device *upper_dev, |
| 4719 | struct list_head *up_list, |
| 4720 | struct list_head *down_list, |
| 4721 | void *private, bool master) |
| 4722 | { |
| 4723 | int ret; |
| 4724 | |
| 4725 | ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private, |
| 4726 | master); |
| 4727 | if (ret) |
| 4728 | return ret; |
| 4729 | |
| 4730 | ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private, |
| 4731 | false); |
| 4732 | if (ret) { |
| 4733 | __netdev_adjacent_dev_remove(dev, upper_dev, up_list); |
| 4734 | return ret; |
| 4735 | } |
| 4736 | |
| 4737 | return 0; |
| 4738 | } |
| 4739 | |
| 4740 | static int __netdev_adjacent_dev_link(struct net_device *dev, |
| 4741 | struct net_device *upper_dev) |
| 4742 | { |
| 4743 | return __netdev_adjacent_dev_link_lists(dev, upper_dev, |
| 4744 | &dev->all_adj_list.upper, |
| 4745 | &upper_dev->all_adj_list.lower, |
| 4746 | NULL, false); |
| 4747 | } |
| 4748 | |
| 4749 | static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, |
| 4750 | struct net_device *upper_dev, |
| 4751 | struct list_head *up_list, |
| 4752 | struct list_head *down_list) |
| 4753 | { |
| 4754 | __netdev_adjacent_dev_remove(dev, upper_dev, up_list); |
| 4755 | __netdev_adjacent_dev_remove(upper_dev, dev, down_list); |
| 4756 | } |
| 4757 | |
| 4758 | static void __netdev_adjacent_dev_unlink(struct net_device *dev, |
| 4759 | struct net_device *upper_dev) |
| 4760 | { |
| 4761 | __netdev_adjacent_dev_unlink_lists(dev, upper_dev, |
| 4762 | &dev->all_adj_list.upper, |
| 4763 | &upper_dev->all_adj_list.lower); |
| 4764 | } |
| 4765 | |
| 4766 | static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, |
| 4767 | struct net_device *upper_dev, |
| 4768 | void *private, bool master) |
| 4769 | { |
| 4770 | int ret = __netdev_adjacent_dev_link(dev, upper_dev); |
| 4771 | |
| 4772 | if (ret) |
| 4773 | return ret; |
| 4774 | |
| 4775 | ret = __netdev_adjacent_dev_link_lists(dev, upper_dev, |
| 4776 | &dev->adj_list.upper, |
| 4777 | &upper_dev->adj_list.lower, |
| 4778 | private, master); |
| 4779 | if (ret) { |
| 4780 | __netdev_adjacent_dev_unlink(dev, upper_dev); |
| 4781 | return ret; |
| 4782 | } |
| 4783 | |
| 4784 | return 0; |
| 4785 | } |
| 4786 | |
| 4787 | static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, |
| 4788 | struct net_device *upper_dev) |
| 4789 | { |
| 4790 | __netdev_adjacent_dev_unlink(dev, upper_dev); |
| 4791 | __netdev_adjacent_dev_unlink_lists(dev, upper_dev, |
| 4792 | &dev->adj_list.upper, |
| 4793 | &upper_dev->adj_list.lower); |
| 4794 | } |
| 4795 | |
| 4796 | static int __netdev_upper_dev_link(struct net_device *dev, |
| 4797 | struct net_device *upper_dev, bool master, |
| 4798 | void *private) |
| 4799 | { |
| 4800 | struct netdev_adjacent *i, *j, *to_i, *to_j; |
| 4801 | int ret = 0; |
| 4802 | |
| 4803 | ASSERT_RTNL(); |
| 4804 | |
| 4805 | if (dev == upper_dev) |
| 4806 | return -EBUSY; |
| 4807 | |
| 4808 | /* To prevent loops, check if dev is not upper device to upper_dev. */ |
| 4809 | if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper)) |
| 4810 | return -EBUSY; |
| 4811 | |
| 4812 | if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper)) |
| 4813 | return -EEXIST; |
| 4814 | |
| 4815 | if (master && netdev_master_upper_dev_get(dev)) |
| 4816 | return -EBUSY; |
| 4817 | |
| 4818 | ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private, |
| 4819 | master); |
| 4820 | if (ret) |
| 4821 | return ret; |
| 4822 | |
| 4823 | /* Now that we linked these devs, make all the upper_dev's |
| 4824 | * all_adj_list.upper visible to every dev's all_adj_list.lower an |
| 4825 | * versa, and don't forget the devices itself. All of these |
| 4826 | * links are non-neighbours. |
| 4827 | */ |
| 4828 | list_for_each_entry(i, &dev->all_adj_list.lower, list) { |
| 4829 | list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) { |
| 4830 | pr_debug("Interlinking %s with %s, non-neighbour\n", |
| 4831 | i->dev->name, j->dev->name); |
| 4832 | ret = __netdev_adjacent_dev_link(i->dev, j->dev); |
| 4833 | if (ret) |
| 4834 | goto rollback_mesh; |
| 4835 | } |
| 4836 | } |
| 4837 | |
| 4838 | /* add dev to every upper_dev's upper device */ |
| 4839 | list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) { |
| 4840 | pr_debug("linking %s's upper device %s with %s\n", |
| 4841 | upper_dev->name, i->dev->name, dev->name); |
| 4842 | ret = __netdev_adjacent_dev_link(dev, i->dev); |
| 4843 | if (ret) |
| 4844 | goto rollback_upper_mesh; |
| 4845 | } |
| 4846 | |
| 4847 | /* add upper_dev to every dev's lower device */ |
| 4848 | list_for_each_entry(i, &dev->all_adj_list.lower, list) { |
| 4849 | pr_debug("linking %s's lower device %s with %s\n", dev->name, |
| 4850 | i->dev->name, upper_dev->name); |
| 4851 | ret = __netdev_adjacent_dev_link(i->dev, upper_dev); |
| 4852 | if (ret) |
| 4853 | goto rollback_lower_mesh; |
| 4854 | } |
| 4855 | |
| 4856 | call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev); |
| 4857 | return 0; |
| 4858 | |
| 4859 | rollback_lower_mesh: |
| 4860 | to_i = i; |
| 4861 | list_for_each_entry(i, &dev->all_adj_list.lower, list) { |
| 4862 | if (i == to_i) |
| 4863 | break; |
| 4864 | __netdev_adjacent_dev_unlink(i->dev, upper_dev); |
| 4865 | } |
| 4866 | |
| 4867 | i = NULL; |
| 4868 | |
| 4869 | rollback_upper_mesh: |
| 4870 | to_i = i; |
| 4871 | list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) { |
| 4872 | if (i == to_i) |
| 4873 | break; |
| 4874 | __netdev_adjacent_dev_unlink(dev, i->dev); |
| 4875 | } |
| 4876 | |
| 4877 | i = j = NULL; |
| 4878 | |
| 4879 | rollback_mesh: |
| 4880 | to_i = i; |
| 4881 | to_j = j; |
| 4882 | list_for_each_entry(i, &dev->all_adj_list.lower, list) { |
| 4883 | list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) { |
| 4884 | if (i == to_i && j == to_j) |
| 4885 | break; |
| 4886 | __netdev_adjacent_dev_unlink(i->dev, j->dev); |
| 4887 | } |
| 4888 | if (i == to_i) |
| 4889 | break; |
| 4890 | } |
| 4891 | |
| 4892 | __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); |
| 4893 | |
| 4894 | return ret; |
| 4895 | } |
| 4896 | |
| 4897 | /** |
| 4898 | * netdev_upper_dev_link - Add a link to the upper device |
| 4899 | * @dev: device |
| 4900 | * @upper_dev: new upper device |
| 4901 | * |
| 4902 | * Adds a link to device which is upper to this one. The caller must hold |
| 4903 | * the RTNL lock. On a failure a negative errno code is returned. |
| 4904 | * On success the reference counts are adjusted and the function |
| 4905 | * returns zero. |
| 4906 | */ |
| 4907 | int netdev_upper_dev_link(struct net_device *dev, |
| 4908 | struct net_device *upper_dev) |
| 4909 | { |
| 4910 | return __netdev_upper_dev_link(dev, upper_dev, false, NULL); |
| 4911 | } |
| 4912 | EXPORT_SYMBOL(netdev_upper_dev_link); |
| 4913 | |
| 4914 | /** |
| 4915 | * netdev_master_upper_dev_link - Add a master link to the upper device |
| 4916 | * @dev: device |
| 4917 | * @upper_dev: new upper device |
| 4918 | * |
| 4919 | * Adds a link to device which is upper to this one. In this case, only |
| 4920 | * one master upper device can be linked, although other non-master devices |
| 4921 | * might be linked as well. The caller must hold the RTNL lock. |
| 4922 | * On a failure a negative errno code is returned. On success the reference |
| 4923 | * counts are adjusted and the function returns zero. |
| 4924 | */ |
| 4925 | int netdev_master_upper_dev_link(struct net_device *dev, |
| 4926 | struct net_device *upper_dev) |
| 4927 | { |
| 4928 | return __netdev_upper_dev_link(dev, upper_dev, true, NULL); |
| 4929 | } |
| 4930 | EXPORT_SYMBOL(netdev_master_upper_dev_link); |
| 4931 | |
| 4932 | int netdev_master_upper_dev_link_private(struct net_device *dev, |
| 4933 | struct net_device *upper_dev, |
| 4934 | void *private) |
| 4935 | { |
| 4936 | return __netdev_upper_dev_link(dev, upper_dev, true, private); |
| 4937 | } |
| 4938 | EXPORT_SYMBOL(netdev_master_upper_dev_link_private); |
| 4939 | |
| 4940 | /** |
| 4941 | * netdev_upper_dev_unlink - Removes a link to upper device |
| 4942 | * @dev: device |
| 4943 | * @upper_dev: new upper device |
| 4944 | * |
| 4945 | * Removes a link to device which is upper to this one. The caller must hold |
| 4946 | * the RTNL lock. |
| 4947 | */ |
| 4948 | void netdev_upper_dev_unlink(struct net_device *dev, |
| 4949 | struct net_device *upper_dev) |
| 4950 | { |
| 4951 | struct netdev_adjacent *i, *j; |
| 4952 | ASSERT_RTNL(); |
| 4953 | |
| 4954 | __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); |
| 4955 | |
| 4956 | /* Here is the tricky part. We must remove all dev's lower |
| 4957 | * devices from all upper_dev's upper devices and vice |
| 4958 | * versa, to maintain the graph relationship. |
| 4959 | */ |
| 4960 | list_for_each_entry(i, &dev->all_adj_list.lower, list) |
| 4961 | list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) |
| 4962 | __netdev_adjacent_dev_unlink(i->dev, j->dev); |
| 4963 | |
| 4964 | /* remove also the devices itself from lower/upper device |
| 4965 | * list |
| 4966 | */ |
| 4967 | list_for_each_entry(i, &dev->all_adj_list.lower, list) |
| 4968 | __netdev_adjacent_dev_unlink(i->dev, upper_dev); |
| 4969 | |
| 4970 | list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) |
| 4971 | __netdev_adjacent_dev_unlink(dev, i->dev); |
| 4972 | |
| 4973 | call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev); |
| 4974 | } |
| 4975 | EXPORT_SYMBOL(netdev_upper_dev_unlink); |
| 4976 | |
| 4977 | void *netdev_lower_dev_get_private(struct net_device *dev, |
| 4978 | struct net_device *lower_dev) |
| 4979 | { |
| 4980 | struct netdev_adjacent *lower; |
| 4981 | |
| 4982 | if (!lower_dev) |
| 4983 | return NULL; |
| 4984 | lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower); |
| 4985 | if (!lower) |
| 4986 | return NULL; |
| 4987 | |
| 4988 | return lower->private; |
| 4989 | } |
| 4990 | EXPORT_SYMBOL(netdev_lower_dev_get_private); |
| 4991 | |
| 4992 | static void dev_change_rx_flags(struct net_device *dev, int flags) |
| 4993 | { |
| 4994 | const struct net_device_ops *ops = dev->netdev_ops; |
| 4995 | |
| 4996 | if (ops->ndo_change_rx_flags) |
| 4997 | ops->ndo_change_rx_flags(dev, flags); |
| 4998 | } |
| 4999 | |
| 5000 | static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) |
| 5001 | { |
| 5002 | unsigned int old_flags = dev->flags; |
| 5003 | kuid_t uid; |
| 5004 | kgid_t gid; |
| 5005 | |
| 5006 | ASSERT_RTNL(); |
| 5007 | |
| 5008 | dev->flags |= IFF_PROMISC; |
| 5009 | dev->promiscuity += inc; |
| 5010 | if (dev->promiscuity == 0) { |
| 5011 | /* |
| 5012 | * Avoid overflow. |
| 5013 | * If inc causes overflow, untouch promisc and return error. |
| 5014 | */ |
| 5015 | if (inc < 0) |
| 5016 | dev->flags &= ~IFF_PROMISC; |
| 5017 | else { |
| 5018 | dev->promiscuity -= inc; |
| 5019 | pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n", |
| 5020 | dev->name); |
| 5021 | return -EOVERFLOW; |
| 5022 | } |
| 5023 | } |
| 5024 | if (dev->flags != old_flags) { |
| 5025 | pr_info("device %s %s promiscuous mode\n", |
| 5026 | dev->name, |
| 5027 | dev->flags & IFF_PROMISC ? "entered" : "left"); |
| 5028 | if (audit_enabled) { |
| 5029 | current_uid_gid(&uid, &gid); |
| 5030 | audit_log(current->audit_context, GFP_ATOMIC, |
| 5031 | AUDIT_ANOM_PROMISCUOUS, |
| 5032 | "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", |
| 5033 | dev->name, (dev->flags & IFF_PROMISC), |
| 5034 | (old_flags & IFF_PROMISC), |
| 5035 | from_kuid(&init_user_ns, audit_get_loginuid(current)), |
| 5036 | from_kuid(&init_user_ns, uid), |
| 5037 | from_kgid(&init_user_ns, gid), |
| 5038 | audit_get_sessionid(current)); |
| 5039 | } |
| 5040 | |
| 5041 | dev_change_rx_flags(dev, IFF_PROMISC); |
| 5042 | } |
| 5043 | if (notify) |
| 5044 | __dev_notify_flags(dev, old_flags, IFF_PROMISC); |
| 5045 | return 0; |
| 5046 | } |
| 5047 | |
| 5048 | /** |
| 5049 | * dev_set_promiscuity - update promiscuity count on a device |
| 5050 | * @dev: device |
| 5051 | * @inc: modifier |
| 5052 | * |
| 5053 | * Add or remove promiscuity from a device. While the count in the device |
| 5054 | * remains above zero the interface remains promiscuous. Once it hits zero |
| 5055 | * the device reverts back to normal filtering operation. A negative inc |
| 5056 | * value is used to drop promiscuity on the device. |
| 5057 | * Return 0 if successful or a negative errno code on error. |
| 5058 | */ |
| 5059 | int dev_set_promiscuity(struct net_device *dev, int inc) |
| 5060 | { |
| 5061 | unsigned int old_flags = dev->flags; |
| 5062 | int err; |
| 5063 | |
| 5064 | err = __dev_set_promiscuity(dev, inc, true); |
| 5065 | if (err < 0) |
| 5066 | return err; |
| 5067 | if (dev->flags != old_flags) |
| 5068 | dev_set_rx_mode(dev); |
| 5069 | return err; |
| 5070 | } |
| 5071 | EXPORT_SYMBOL(dev_set_promiscuity); |
| 5072 | |
| 5073 | static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) |
| 5074 | { |
| 5075 | unsigned int old_flags = dev->flags, old_gflags = dev->gflags; |
| 5076 | |
| 5077 | ASSERT_RTNL(); |
| 5078 | |
| 5079 | dev->flags |= IFF_ALLMULTI; |
| 5080 | dev->allmulti += inc; |
| 5081 | if (dev->allmulti == 0) { |
| 5082 | /* |
| 5083 | * Avoid overflow. |
| 5084 | * If inc causes overflow, untouch allmulti and return error. |
| 5085 | */ |
| 5086 | if (inc < 0) |
| 5087 | dev->flags &= ~IFF_ALLMULTI; |
| 5088 | else { |
| 5089 | dev->allmulti -= inc; |
| 5090 | pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n", |
| 5091 | dev->name); |
| 5092 | return -EOVERFLOW; |
| 5093 | } |
| 5094 | } |
| 5095 | if (dev->flags ^ old_flags) { |
| 5096 | dev_change_rx_flags(dev, IFF_ALLMULTI); |
| 5097 | dev_set_rx_mode(dev); |
| 5098 | if (notify) |
| 5099 | __dev_notify_flags(dev, old_flags, |
| 5100 | dev->gflags ^ old_gflags); |
| 5101 | } |
| 5102 | return 0; |
| 5103 | } |
| 5104 | |
| 5105 | /** |
| 5106 | * dev_set_allmulti - update allmulti count on a device |
| 5107 | * @dev: device |
| 5108 | * @inc: modifier |
| 5109 | * |
| 5110 | * Add or remove reception of all multicast frames to a device. While the |
| 5111 | * count in the device remains above zero the interface remains listening |
| 5112 | * to all interfaces. Once it hits zero the device reverts back to normal |
| 5113 | * filtering operation. A negative @inc value is used to drop the counter |
| 5114 | * when releasing a resource needing all multicasts. |
| 5115 | * Return 0 if successful or a negative errno code on error. |
| 5116 | */ |
| 5117 | |
| 5118 | int dev_set_allmulti(struct net_device *dev, int inc) |
| 5119 | { |
| 5120 | return __dev_set_allmulti(dev, inc, true); |
| 5121 | } |
| 5122 | EXPORT_SYMBOL(dev_set_allmulti); |
| 5123 | |
| 5124 | /* |
| 5125 | * Upload unicast and multicast address lists to device and |
| 5126 | * configure RX filtering. When the device doesn't support unicast |
| 5127 | * filtering it is put in promiscuous mode while unicast addresses |
| 5128 | * are present. |
| 5129 | */ |
| 5130 | void __dev_set_rx_mode(struct net_device *dev) |
| 5131 | { |
| 5132 | const struct net_device_ops *ops = dev->netdev_ops; |
| 5133 | |
| 5134 | /* dev_open will call this function so the list will stay sane. */ |
| 5135 | if (!(dev->flags&IFF_UP)) |
| 5136 | return; |
| 5137 | |
| 5138 | if (!netif_device_present(dev)) |
| 5139 | return; |
| 5140 | |
| 5141 | if (!(dev->priv_flags & IFF_UNICAST_FLT)) { |
| 5142 | /* Unicast addresses changes may only happen under the rtnl, |
| 5143 | * therefore calling __dev_set_promiscuity here is safe. |
| 5144 | */ |
| 5145 | if (!netdev_uc_empty(dev) && !dev->uc_promisc) { |
| 5146 | __dev_set_promiscuity(dev, 1, false); |
| 5147 | dev->uc_promisc = true; |
| 5148 | } else if (netdev_uc_empty(dev) && dev->uc_promisc) { |
| 5149 | __dev_set_promiscuity(dev, -1, false); |
| 5150 | dev->uc_promisc = false; |
| 5151 | } |
| 5152 | } |
| 5153 | |
| 5154 | if (ops->ndo_set_rx_mode) |
| 5155 | ops->ndo_set_rx_mode(dev); |
| 5156 | } |
| 5157 | |
| 5158 | void dev_set_rx_mode(struct net_device *dev) |
| 5159 | { |
| 5160 | netif_addr_lock_bh(dev); |
| 5161 | __dev_set_rx_mode(dev); |
| 5162 | netif_addr_unlock_bh(dev); |
| 5163 | } |
| 5164 | |
| 5165 | /** |
| 5166 | * dev_get_flags - get flags reported to userspace |
| 5167 | * @dev: device |
| 5168 | * |
| 5169 | * Get the combination of flag bits exported through APIs to userspace. |
| 5170 | */ |
| 5171 | unsigned int dev_get_flags(const struct net_device *dev) |
| 5172 | { |
| 5173 | unsigned int flags; |
| 5174 | |
| 5175 | flags = (dev->flags & ~(IFF_PROMISC | |
| 5176 | IFF_ALLMULTI | |
| 5177 | IFF_RUNNING | |
| 5178 | IFF_LOWER_UP | |
| 5179 | IFF_DORMANT)) | |
| 5180 | (dev->gflags & (IFF_PROMISC | |
| 5181 | IFF_ALLMULTI)); |
| 5182 | |
| 5183 | if (netif_running(dev)) { |
| 5184 | if (netif_oper_up(dev)) |
| 5185 | flags |= IFF_RUNNING; |
| 5186 | if (netif_carrier_ok(dev)) |
| 5187 | flags |= IFF_LOWER_UP; |
| 5188 | if (netif_dormant(dev)) |
| 5189 | flags |= IFF_DORMANT; |
| 5190 | } |
| 5191 | |
| 5192 | return flags; |
| 5193 | } |
| 5194 | EXPORT_SYMBOL(dev_get_flags); |
| 5195 | |
| 5196 | int __dev_change_flags(struct net_device *dev, unsigned int flags) |
| 5197 | { |
| 5198 | unsigned int old_flags = dev->flags; |
| 5199 | int ret; |
| 5200 | |
| 5201 | ASSERT_RTNL(); |
| 5202 | |
| 5203 | /* |
| 5204 | * Set the flags on our device. |
| 5205 | */ |
| 5206 | |
| 5207 | dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | |
| 5208 | IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | |
| 5209 | IFF_AUTOMEDIA)) | |
| 5210 | (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | |
| 5211 | IFF_ALLMULTI)); |
| 5212 | |
| 5213 | /* |
| 5214 | * Load in the correct multicast list now the flags have changed. |
| 5215 | */ |
| 5216 | |
| 5217 | if ((old_flags ^ flags) & IFF_MULTICAST) |
| 5218 | dev_change_rx_flags(dev, IFF_MULTICAST); |
| 5219 | |
| 5220 | dev_set_rx_mode(dev); |
| 5221 | |
| 5222 | /* |
| 5223 | * Have we downed the interface. We handle IFF_UP ourselves |
| 5224 | * according to user attempts to set it, rather than blindly |
| 5225 | * setting it. |
| 5226 | */ |
| 5227 | |
| 5228 | ret = 0; |
| 5229 | if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ |
| 5230 | ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev); |
| 5231 | |
| 5232 | if (!ret) |
| 5233 | dev_set_rx_mode(dev); |
| 5234 | } |
| 5235 | |
| 5236 | if ((flags ^ dev->gflags) & IFF_PROMISC) { |
| 5237 | int inc = (flags & IFF_PROMISC) ? 1 : -1; |
| 5238 | unsigned int old_flags = dev->flags; |
| 5239 | |
| 5240 | dev->gflags ^= IFF_PROMISC; |
| 5241 | |
| 5242 | if (__dev_set_promiscuity(dev, inc, false) >= 0) |
| 5243 | if (dev->flags != old_flags) |
| 5244 | dev_set_rx_mode(dev); |
| 5245 | } |
| 5246 | |
| 5247 | /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI |
| 5248 | is important. Some (broken) drivers set IFF_PROMISC, when |
| 5249 | IFF_ALLMULTI is requested not asking us and not reporting. |
| 5250 | */ |
| 5251 | if ((flags ^ dev->gflags) & IFF_ALLMULTI) { |
| 5252 | int inc = (flags & IFF_ALLMULTI) ? 1 : -1; |
| 5253 | |
| 5254 | dev->gflags ^= IFF_ALLMULTI; |
| 5255 | __dev_set_allmulti(dev, inc, false); |
| 5256 | } |
| 5257 | |
| 5258 | return ret; |
| 5259 | } |
| 5260 | |
| 5261 | void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, |
| 5262 | unsigned int gchanges) |
| 5263 | { |
| 5264 | unsigned int changes = dev->flags ^ old_flags; |
| 5265 | |
| 5266 | if (gchanges) |
| 5267 | rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC); |
| 5268 | |
| 5269 | if (changes & IFF_UP) { |
| 5270 | if (dev->flags & IFF_UP) |
| 5271 | call_netdevice_notifiers(NETDEV_UP, dev); |
| 5272 | else |
| 5273 | call_netdevice_notifiers(NETDEV_DOWN, dev); |
| 5274 | } |
| 5275 | |
| 5276 | if (dev->flags & IFF_UP && |
| 5277 | (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { |
| 5278 | struct netdev_notifier_change_info change_info; |
| 5279 | |
| 5280 | change_info.flags_changed = changes; |
| 5281 | call_netdevice_notifiers_info(NETDEV_CHANGE, dev, |
| 5282 | &change_info.info); |
| 5283 | } |
| 5284 | } |
| 5285 | |
| 5286 | /** |
| 5287 | * dev_change_flags - change device settings |
| 5288 | * @dev: device |
| 5289 | * @flags: device state flags |
| 5290 | * |
| 5291 | * Change settings on device based state flags. The flags are |
| 5292 | * in the userspace exported format. |
| 5293 | */ |
| 5294 | int dev_change_flags(struct net_device *dev, unsigned int flags) |
| 5295 | { |
| 5296 | int ret; |
| 5297 | unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; |
| 5298 | |
| 5299 | ret = __dev_change_flags(dev, flags); |
| 5300 | if (ret < 0) |
| 5301 | return ret; |
| 5302 | |
| 5303 | changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); |
| 5304 | __dev_notify_flags(dev, old_flags, changes); |
| 5305 | return ret; |
| 5306 | } |
| 5307 | EXPORT_SYMBOL(dev_change_flags); |
| 5308 | |
| 5309 | static int __dev_set_mtu(struct net_device *dev, int new_mtu) |
| 5310 | { |
| 5311 | const struct net_device_ops *ops = dev->netdev_ops; |
| 5312 | |
| 5313 | if (ops->ndo_change_mtu) |
| 5314 | return ops->ndo_change_mtu(dev, new_mtu); |
| 5315 | |
| 5316 | dev->mtu = new_mtu; |
| 5317 | return 0; |
| 5318 | } |
| 5319 | |
| 5320 | /** |
| 5321 | * dev_set_mtu - Change maximum transfer unit |
| 5322 | * @dev: device |
| 5323 | * @new_mtu: new transfer unit |
| 5324 | * |
| 5325 | * Change the maximum transfer size of the network device. |
| 5326 | */ |
| 5327 | int dev_set_mtu(struct net_device *dev, int new_mtu) |
| 5328 | { |
| 5329 | int err, orig_mtu; |
| 5330 | |
| 5331 | if (new_mtu == dev->mtu) |
| 5332 | return 0; |
| 5333 | |
| 5334 | /* MTU must be positive. */ |
| 5335 | if (new_mtu < 0) |
| 5336 | return -EINVAL; |
| 5337 | |
| 5338 | if (!netif_device_present(dev)) |
| 5339 | return -ENODEV; |
| 5340 | |
| 5341 | orig_mtu = dev->mtu; |
| 5342 | err = __dev_set_mtu(dev, new_mtu); |
| 5343 | |
| 5344 | if (!err) { |
| 5345 | err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); |
| 5346 | err = notifier_to_errno(err); |
| 5347 | if (err) { |
| 5348 | /* setting mtu back and notifying everyone again, |
| 5349 | * so that they have a chance to revert changes. |
| 5350 | */ |
| 5351 | __dev_set_mtu(dev, orig_mtu); |
| 5352 | call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); |
| 5353 | } |
| 5354 | } |
| 5355 | return err; |
| 5356 | } |
| 5357 | EXPORT_SYMBOL(dev_set_mtu); |
| 5358 | |
| 5359 | /** |
| 5360 | * dev_set_group - Change group this device belongs to |
| 5361 | * @dev: device |
| 5362 | * @new_group: group this device should belong to |
| 5363 | */ |
| 5364 | void dev_set_group(struct net_device *dev, int new_group) |
| 5365 | { |
| 5366 | dev->group = new_group; |
| 5367 | } |
| 5368 | EXPORT_SYMBOL(dev_set_group); |
| 5369 | |
| 5370 | /** |
| 5371 | * dev_set_mac_address - Change Media Access Control Address |
| 5372 | * @dev: device |
| 5373 | * @sa: new address |
| 5374 | * |
| 5375 | * Change the hardware (MAC) address of the device |
| 5376 | */ |
| 5377 | int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) |
| 5378 | { |
| 5379 | const struct net_device_ops *ops = dev->netdev_ops; |
| 5380 | int err; |
| 5381 | |
| 5382 | if (!ops->ndo_set_mac_address) |
| 5383 | return -EOPNOTSUPP; |
| 5384 | if (sa->sa_family != dev->type) |
| 5385 | return -EINVAL; |
| 5386 | if (!netif_device_present(dev)) |
| 5387 | return -ENODEV; |
| 5388 | err = ops->ndo_set_mac_address(dev, sa); |
| 5389 | if (err) |
| 5390 | return err; |
| 5391 | dev->addr_assign_type = NET_ADDR_SET; |
| 5392 | call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); |
| 5393 | add_device_randomness(dev->dev_addr, dev->addr_len); |
| 5394 | return 0; |
| 5395 | } |
| 5396 | EXPORT_SYMBOL(dev_set_mac_address); |
| 5397 | |
| 5398 | /** |
| 5399 | * dev_change_carrier - Change device carrier |
| 5400 | * @dev: device |
| 5401 | * @new_carrier: new value |
| 5402 | * |
| 5403 | * Change device carrier |
| 5404 | */ |
| 5405 | int dev_change_carrier(struct net_device *dev, bool new_carrier) |
| 5406 | { |
| 5407 | const struct net_device_ops *ops = dev->netdev_ops; |
| 5408 | |
| 5409 | if (!ops->ndo_change_carrier) |
| 5410 | return -EOPNOTSUPP; |
| 5411 | if (!netif_device_present(dev)) |
| 5412 | return -ENODEV; |
| 5413 | return ops->ndo_change_carrier(dev, new_carrier); |
| 5414 | } |
| 5415 | EXPORT_SYMBOL(dev_change_carrier); |
| 5416 | |
| 5417 | /** |
| 5418 | * dev_get_phys_port_id - Get device physical port ID |
| 5419 | * @dev: device |
| 5420 | * @ppid: port ID |
| 5421 | * |
| 5422 | * Get device physical port ID |
| 5423 | */ |
| 5424 | int dev_get_phys_port_id(struct net_device *dev, |
| 5425 | struct netdev_phys_port_id *ppid) |
| 5426 | { |
| 5427 | const struct net_device_ops *ops = dev->netdev_ops; |
| 5428 | |
| 5429 | if (!ops->ndo_get_phys_port_id) |
| 5430 | return -EOPNOTSUPP; |
| 5431 | return ops->ndo_get_phys_port_id(dev, ppid); |
| 5432 | } |
| 5433 | EXPORT_SYMBOL(dev_get_phys_port_id); |
| 5434 | |
| 5435 | /** |
| 5436 | * dev_new_index - allocate an ifindex |
| 5437 | * @net: the applicable net namespace |
| 5438 | * |
| 5439 | * Returns a suitable unique value for a new device interface |
| 5440 | * number. The caller must hold the rtnl semaphore or the |
| 5441 | * dev_base_lock to be sure it remains unique. |
| 5442 | */ |
| 5443 | static int dev_new_index(struct net *net) |
| 5444 | { |
| 5445 | int ifindex = net->ifindex; |
| 5446 | for (;;) { |
| 5447 | if (++ifindex <= 0) |
| 5448 | ifindex = 1; |
| 5449 | if (!__dev_get_by_index(net, ifindex)) |
| 5450 | return net->ifindex = ifindex; |
| 5451 | } |
| 5452 | } |
| 5453 | |
| 5454 | /* Delayed registration/unregisteration */ |
| 5455 | static LIST_HEAD(net_todo_list); |
| 5456 | static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); |
| 5457 | |
| 5458 | static void net_set_todo(struct net_device *dev) |
| 5459 | { |
| 5460 | list_add_tail(&dev->todo_list, &net_todo_list); |
| 5461 | dev_net(dev)->dev_unreg_count++; |
| 5462 | } |
| 5463 | |
| 5464 | static void rollback_registered_many(struct list_head *head) |
| 5465 | { |
| 5466 | struct net_device *dev, *tmp; |
| 5467 | LIST_HEAD(close_head); |
| 5468 | |
| 5469 | BUG_ON(dev_boot_phase); |
| 5470 | ASSERT_RTNL(); |
| 5471 | |
| 5472 | list_for_each_entry_safe(dev, tmp, head, unreg_list) { |
| 5473 | /* Some devices call without registering |
| 5474 | * for initialization unwind. Remove those |
| 5475 | * devices and proceed with the remaining. |
| 5476 | */ |
| 5477 | if (dev->reg_state == NETREG_UNINITIALIZED) { |
| 5478 | pr_debug("unregister_netdevice: device %s/%p never was registered\n", |
| 5479 | dev->name, dev); |
| 5480 | |
| 5481 | WARN_ON(1); |
| 5482 | list_del(&dev->unreg_list); |
| 5483 | continue; |
| 5484 | } |
| 5485 | dev->dismantle = true; |
| 5486 | BUG_ON(dev->reg_state != NETREG_REGISTERED); |
| 5487 | } |
| 5488 | |
| 5489 | /* If device is running, close it first. */ |
| 5490 | list_for_each_entry(dev, head, unreg_list) |
| 5491 | list_add_tail(&dev->close_list, &close_head); |
| 5492 | dev_close_many(&close_head); |
| 5493 | |
| 5494 | list_for_each_entry(dev, head, unreg_list) { |
| 5495 | /* And unlink it from device chain. */ |
| 5496 | unlist_netdevice(dev); |
| 5497 | |
| 5498 | dev->reg_state = NETREG_UNREGISTERING; |
| 5499 | } |
| 5500 | |
| 5501 | synchronize_net(); |
| 5502 | |
| 5503 | list_for_each_entry(dev, head, unreg_list) { |
| 5504 | /* Shutdown queueing discipline. */ |
| 5505 | dev_shutdown(dev); |
| 5506 | |
| 5507 | |
| 5508 | /* Notify protocols, that we are about to destroy |
| 5509 | this device. They should clean all the things. |
| 5510 | */ |
| 5511 | call_netdevice_notifiers(NETDEV_UNREGISTER, dev); |
| 5512 | |
| 5513 | if (!dev->rtnl_link_ops || |
| 5514 | dev->rtnl_link_state == RTNL_LINK_INITIALIZED) |
| 5515 | rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL); |
| 5516 | |
| 5517 | /* |
| 5518 | * Flush the unicast and multicast chains |
| 5519 | */ |
| 5520 | dev_uc_flush(dev); |
| 5521 | dev_mc_flush(dev); |
| 5522 | |
| 5523 | if (dev->netdev_ops->ndo_uninit) |
| 5524 | dev->netdev_ops->ndo_uninit(dev); |
| 5525 | |
| 5526 | /* Notifier chain MUST detach us all upper devices. */ |
| 5527 | WARN_ON(netdev_has_any_upper_dev(dev)); |
| 5528 | |
| 5529 | /* Remove entries from kobject tree */ |
| 5530 | netdev_unregister_kobject(dev); |
| 5531 | #ifdef CONFIG_XPS |
| 5532 | /* Remove XPS queueing entries */ |
| 5533 | netif_reset_xps_queues_gt(dev, 0); |
| 5534 | #endif |
| 5535 | } |
| 5536 | |
| 5537 | synchronize_net(); |
| 5538 | |
| 5539 | list_for_each_entry(dev, head, unreg_list) |
| 5540 | dev_put(dev); |
| 5541 | } |
| 5542 | |
| 5543 | static void rollback_registered(struct net_device *dev) |
| 5544 | { |
| 5545 | LIST_HEAD(single); |
| 5546 | |
| 5547 | list_add(&dev->unreg_list, &single); |
| 5548 | rollback_registered_many(&single); |
| 5549 | list_del(&single); |
| 5550 | } |
| 5551 | |
| 5552 | static netdev_features_t netdev_fix_features(struct net_device *dev, |
| 5553 | netdev_features_t features) |
| 5554 | { |
| 5555 | /* Fix illegal checksum combinations */ |
| 5556 | if ((features & NETIF_F_HW_CSUM) && |
| 5557 | (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { |
| 5558 | netdev_warn(dev, "mixed HW and IP checksum settings.\n"); |
| 5559 | features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); |
| 5560 | } |
| 5561 | |
| 5562 | /* TSO requires that SG is present as well. */ |
| 5563 | if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { |
| 5564 | netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); |
| 5565 | features &= ~NETIF_F_ALL_TSO; |
| 5566 | } |
| 5567 | |
| 5568 | if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && |
| 5569 | !(features & NETIF_F_IP_CSUM)) { |
| 5570 | netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); |
| 5571 | features &= ~NETIF_F_TSO; |
| 5572 | features &= ~NETIF_F_TSO_ECN; |
| 5573 | } |
| 5574 | |
| 5575 | if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && |
| 5576 | !(features & NETIF_F_IPV6_CSUM)) { |
| 5577 | netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); |
| 5578 | features &= ~NETIF_F_TSO6; |
| 5579 | } |
| 5580 | |
| 5581 | /* TSO ECN requires that TSO is present as well. */ |
| 5582 | if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) |
| 5583 | features &= ~NETIF_F_TSO_ECN; |
| 5584 | |
| 5585 | /* Software GSO depends on SG. */ |
| 5586 | if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { |
| 5587 | netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); |
| 5588 | features &= ~NETIF_F_GSO; |
| 5589 | } |
| 5590 | |
| 5591 | /* UFO needs SG and checksumming */ |
| 5592 | if (features & NETIF_F_UFO) { |
| 5593 | /* maybe split UFO into V4 and V6? */ |
| 5594 | if (!((features & NETIF_F_GEN_CSUM) || |
| 5595 | (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM)) |
| 5596 | == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { |
| 5597 | netdev_dbg(dev, |
| 5598 | "Dropping NETIF_F_UFO since no checksum offload features.\n"); |
| 5599 | features &= ~NETIF_F_UFO; |
| 5600 | } |
| 5601 | |
| 5602 | if (!(features & NETIF_F_SG)) { |
| 5603 | netdev_dbg(dev, |
| 5604 | "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n"); |
| 5605 | features &= ~NETIF_F_UFO; |
| 5606 | } |
| 5607 | } |
| 5608 | |
| 5609 | return features; |
| 5610 | } |
| 5611 | |
| 5612 | int __netdev_update_features(struct net_device *dev) |
| 5613 | { |
| 5614 | netdev_features_t features; |
| 5615 | int err = 0; |
| 5616 | |
| 5617 | ASSERT_RTNL(); |
| 5618 | |
| 5619 | features = netdev_get_wanted_features(dev); |
| 5620 | |
| 5621 | if (dev->netdev_ops->ndo_fix_features) |
| 5622 | features = dev->netdev_ops->ndo_fix_features(dev, features); |
| 5623 | |
| 5624 | /* driver might be less strict about feature dependencies */ |
| 5625 | features = netdev_fix_features(dev, features); |
| 5626 | |
| 5627 | if (dev->features == features) |
| 5628 | return 0; |
| 5629 | |
| 5630 | netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", |
| 5631 | &dev->features, &features); |
| 5632 | |
| 5633 | if (dev->netdev_ops->ndo_set_features) |
| 5634 | err = dev->netdev_ops->ndo_set_features(dev, features); |
| 5635 | |
| 5636 | if (unlikely(err < 0)) { |
| 5637 | netdev_err(dev, |
| 5638 | "set_features() failed (%d); wanted %pNF, left %pNF\n", |
| 5639 | err, &features, &dev->features); |
| 5640 | return -1; |
| 5641 | } |
| 5642 | |
| 5643 | if (!err) |
| 5644 | dev->features = features; |
| 5645 | |
| 5646 | return 1; |
| 5647 | } |
| 5648 | |
| 5649 | /** |
| 5650 | * netdev_update_features - recalculate device features |
| 5651 | * @dev: the device to check |
| 5652 | * |
| 5653 | * Recalculate dev->features set and send notifications if it |
| 5654 | * has changed. Should be called after driver or hardware dependent |
| 5655 | * conditions might have changed that influence the features. |
| 5656 | */ |
| 5657 | void netdev_update_features(struct net_device *dev) |
| 5658 | { |
| 5659 | if (__netdev_update_features(dev)) |
| 5660 | netdev_features_change(dev); |
| 5661 | } |
| 5662 | EXPORT_SYMBOL(netdev_update_features); |
| 5663 | |
| 5664 | /** |
| 5665 | * netdev_change_features - recalculate device features |
| 5666 | * @dev: the device to check |
| 5667 | * |
| 5668 | * Recalculate dev->features set and send notifications even |
| 5669 | * if they have not changed. Should be called instead of |
| 5670 | * netdev_update_features() if also dev->vlan_features might |
| 5671 | * have changed to allow the changes to be propagated to stacked |
| 5672 | * VLAN devices. |
| 5673 | */ |
| 5674 | void netdev_change_features(struct net_device *dev) |
| 5675 | { |
| 5676 | __netdev_update_features(dev); |
| 5677 | netdev_features_change(dev); |
| 5678 | } |
| 5679 | EXPORT_SYMBOL(netdev_change_features); |
| 5680 | |
| 5681 | /** |
| 5682 | * netif_stacked_transfer_operstate - transfer operstate |
| 5683 | * @rootdev: the root or lower level device to transfer state from |
| 5684 | * @dev: the device to transfer operstate to |
| 5685 | * |
| 5686 | * Transfer operational state from root to device. This is normally |
| 5687 | * called when a stacking relationship exists between the root |
| 5688 | * device and the device(a leaf device). |
| 5689 | */ |
| 5690 | void netif_stacked_transfer_operstate(const struct net_device *rootdev, |
| 5691 | struct net_device *dev) |
| 5692 | { |
| 5693 | if (rootdev->operstate == IF_OPER_DORMANT) |
| 5694 | netif_dormant_on(dev); |
| 5695 | else |
| 5696 | netif_dormant_off(dev); |
| 5697 | |
| 5698 | if (netif_carrier_ok(rootdev)) { |
| 5699 | if (!netif_carrier_ok(dev)) |
| 5700 | netif_carrier_on(dev); |
| 5701 | } else { |
| 5702 | if (netif_carrier_ok(dev)) |
| 5703 | netif_carrier_off(dev); |
| 5704 | } |
| 5705 | } |
| 5706 | EXPORT_SYMBOL(netif_stacked_transfer_operstate); |
| 5707 | |
| 5708 | #ifdef CONFIG_RPS |
| 5709 | static int netif_alloc_rx_queues(struct net_device *dev) |
| 5710 | { |
| 5711 | unsigned int i, count = dev->num_rx_queues; |
| 5712 | struct netdev_rx_queue *rx; |
| 5713 | |
| 5714 | BUG_ON(count < 1); |
| 5715 | |
| 5716 | rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL); |
| 5717 | if (!rx) |
| 5718 | return -ENOMEM; |
| 5719 | |
| 5720 | dev->_rx = rx; |
| 5721 | |
| 5722 | for (i = 0; i < count; i++) |
| 5723 | rx[i].dev = dev; |
| 5724 | return 0; |
| 5725 | } |
| 5726 | #endif |
| 5727 | |
| 5728 | static void netdev_init_one_queue(struct net_device *dev, |
| 5729 | struct netdev_queue *queue, void *_unused) |
| 5730 | { |
| 5731 | /* Initialize queue lock */ |
| 5732 | spin_lock_init(&queue->_xmit_lock); |
| 5733 | netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); |
| 5734 | queue->xmit_lock_owner = -1; |
| 5735 | netdev_queue_numa_node_write(queue, NUMA_NO_NODE); |
| 5736 | queue->dev = dev; |
| 5737 | #ifdef CONFIG_BQL |
| 5738 | dql_init(&queue->dql, HZ); |
| 5739 | #endif |
| 5740 | } |
| 5741 | |
| 5742 | static void netif_free_tx_queues(struct net_device *dev) |
| 5743 | { |
| 5744 | if (is_vmalloc_addr(dev->_tx)) |
| 5745 | vfree(dev->_tx); |
| 5746 | else |
| 5747 | kfree(dev->_tx); |
| 5748 | } |
| 5749 | |
| 5750 | static int netif_alloc_netdev_queues(struct net_device *dev) |
| 5751 | { |
| 5752 | unsigned int count = dev->num_tx_queues; |
| 5753 | struct netdev_queue *tx; |
| 5754 | size_t sz = count * sizeof(*tx); |
| 5755 | |
| 5756 | BUG_ON(count < 1 || count > 0xffff); |
| 5757 | |
| 5758 | tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); |
| 5759 | if (!tx) { |
| 5760 | tx = vzalloc(sz); |
| 5761 | if (!tx) |
| 5762 | return -ENOMEM; |
| 5763 | } |
| 5764 | dev->_tx = tx; |
| 5765 | |
| 5766 | netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); |
| 5767 | spin_lock_init(&dev->tx_global_lock); |
| 5768 | |
| 5769 | return 0; |
| 5770 | } |
| 5771 | |
| 5772 | /** |
| 5773 | * register_netdevice - register a network device |
| 5774 | * @dev: device to register |
| 5775 | * |
| 5776 | * Take a completed network device structure and add it to the kernel |
| 5777 | * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier |
| 5778 | * chain. 0 is returned on success. A negative errno code is returned |
| 5779 | * on a failure to set up the device, or if the name is a duplicate. |
| 5780 | * |
| 5781 | * Callers must hold the rtnl semaphore. You may want |
| 5782 | * register_netdev() instead of this. |
| 5783 | * |
| 5784 | * BUGS: |
| 5785 | * The locking appears insufficient to guarantee two parallel registers |
| 5786 | * will not get the same name. |
| 5787 | */ |
| 5788 | |
| 5789 | int register_netdevice(struct net_device *dev) |
| 5790 | { |
| 5791 | int ret; |
| 5792 | struct net *net = dev_net(dev); |
| 5793 | |
| 5794 | BUG_ON(dev_boot_phase); |
| 5795 | ASSERT_RTNL(); |
| 5796 | |
| 5797 | might_sleep(); |
| 5798 | |
| 5799 | /* When net_device's are persistent, this will be fatal. */ |
| 5800 | BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); |
| 5801 | BUG_ON(!net); |
| 5802 | |
| 5803 | spin_lock_init(&dev->addr_list_lock); |
| 5804 | netdev_set_addr_lockdep_class(dev); |
| 5805 | |
| 5806 | dev->iflink = -1; |
| 5807 | |
| 5808 | ret = dev_get_valid_name(net, dev, dev->name); |
| 5809 | if (ret < 0) |
| 5810 | goto out; |
| 5811 | |
| 5812 | /* Init, if this function is available */ |
| 5813 | if (dev->netdev_ops->ndo_init) { |
| 5814 | ret = dev->netdev_ops->ndo_init(dev); |
| 5815 | if (ret) { |
| 5816 | if (ret > 0) |
| 5817 | ret = -EIO; |
| 5818 | goto out; |
| 5819 | } |
| 5820 | } |
| 5821 | |
| 5822 | if (((dev->hw_features | dev->features) & |
| 5823 | NETIF_F_HW_VLAN_CTAG_FILTER) && |
| 5824 | (!dev->netdev_ops->ndo_vlan_rx_add_vid || |
| 5825 | !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { |
| 5826 | netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); |
| 5827 | ret = -EINVAL; |
| 5828 | goto err_uninit; |
| 5829 | } |
| 5830 | |
| 5831 | ret = -EBUSY; |
| 5832 | if (!dev->ifindex) |
| 5833 | dev->ifindex = dev_new_index(net); |
| 5834 | else if (__dev_get_by_index(net, dev->ifindex)) |
| 5835 | goto err_uninit; |
| 5836 | |
| 5837 | if (dev->iflink == -1) |
| 5838 | dev->iflink = dev->ifindex; |
| 5839 | |
| 5840 | /* Transfer changeable features to wanted_features and enable |
| 5841 | * software offloads (GSO and GRO). |
| 5842 | */ |
| 5843 | dev->hw_features |= NETIF_F_SOFT_FEATURES; |
| 5844 | dev->features |= NETIF_F_SOFT_FEATURES; |
| 5845 | dev->wanted_features = dev->features & dev->hw_features; |
| 5846 | |
| 5847 | if (!(dev->flags & IFF_LOOPBACK)) { |
| 5848 | dev->hw_features |= NETIF_F_NOCACHE_COPY; |
| 5849 | } |
| 5850 | |
| 5851 | /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. |
| 5852 | */ |
| 5853 | dev->vlan_features |= NETIF_F_HIGHDMA; |
| 5854 | |
| 5855 | /* Make NETIF_F_SG inheritable to tunnel devices. |
| 5856 | */ |
| 5857 | dev->hw_enc_features |= NETIF_F_SG; |
| 5858 | |
| 5859 | /* Make NETIF_F_SG inheritable to MPLS. |
| 5860 | */ |
| 5861 | dev->mpls_features |= NETIF_F_SG; |
| 5862 | |
| 5863 | ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); |
| 5864 | ret = notifier_to_errno(ret); |
| 5865 | if (ret) |
| 5866 | goto err_uninit; |
| 5867 | |
| 5868 | ret = netdev_register_kobject(dev); |
| 5869 | if (ret) |
| 5870 | goto err_uninit; |
| 5871 | dev->reg_state = NETREG_REGISTERED; |
| 5872 | |
| 5873 | __netdev_update_features(dev); |
| 5874 | |
| 5875 | /* |
| 5876 | * Default initial state at registry is that the |
| 5877 | * device is present. |
| 5878 | */ |
| 5879 | |
| 5880 | set_bit(__LINK_STATE_PRESENT, &dev->state); |
| 5881 | |
| 5882 | linkwatch_init_dev(dev); |
| 5883 | |
| 5884 | dev_init_scheduler(dev); |
| 5885 | dev_hold(dev); |
| 5886 | list_netdevice(dev); |
| 5887 | add_device_randomness(dev->dev_addr, dev->addr_len); |
| 5888 | |
| 5889 | /* If the device has permanent device address, driver should |
| 5890 | * set dev_addr and also addr_assign_type should be set to |
| 5891 | * NET_ADDR_PERM (default value). |
| 5892 | */ |
| 5893 | if (dev->addr_assign_type == NET_ADDR_PERM) |
| 5894 | memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); |
| 5895 | |
| 5896 | /* Notify protocols, that a new device appeared. */ |
| 5897 | ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); |
| 5898 | ret = notifier_to_errno(ret); |
| 5899 | if (ret) { |
| 5900 | rollback_registered(dev); |
| 5901 | dev->reg_state = NETREG_UNREGISTERED; |
| 5902 | } |
| 5903 | /* |
| 5904 | * Prevent userspace races by waiting until the network |
| 5905 | * device is fully setup before sending notifications. |
| 5906 | */ |
| 5907 | if (!dev->rtnl_link_ops || |
| 5908 | dev->rtnl_link_state == RTNL_LINK_INITIALIZED) |
| 5909 | rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); |
| 5910 | |
| 5911 | out: |
| 5912 | return ret; |
| 5913 | |
| 5914 | err_uninit: |
| 5915 | if (dev->netdev_ops->ndo_uninit) |
| 5916 | dev->netdev_ops->ndo_uninit(dev); |
| 5917 | goto out; |
| 5918 | } |
| 5919 | EXPORT_SYMBOL(register_netdevice); |
| 5920 | |
| 5921 | /** |
| 5922 | * init_dummy_netdev - init a dummy network device for NAPI |
| 5923 | * @dev: device to init |
| 5924 | * |
| 5925 | * This takes a network device structure and initialize the minimum |
| 5926 | * amount of fields so it can be used to schedule NAPI polls without |
| 5927 | * registering a full blown interface. This is to be used by drivers |
| 5928 | * that need to tie several hardware interfaces to a single NAPI |
| 5929 | * poll scheduler due to HW limitations. |
| 5930 | */ |
| 5931 | int init_dummy_netdev(struct net_device *dev) |
| 5932 | { |
| 5933 | /* Clear everything. Note we don't initialize spinlocks |
| 5934 | * are they aren't supposed to be taken by any of the |
| 5935 | * NAPI code and this dummy netdev is supposed to be |
| 5936 | * only ever used for NAPI polls |
| 5937 | */ |
| 5938 | memset(dev, 0, sizeof(struct net_device)); |
| 5939 | |
| 5940 | /* make sure we BUG if trying to hit standard |
| 5941 | * register/unregister code path |
| 5942 | */ |
| 5943 | dev->reg_state = NETREG_DUMMY; |
| 5944 | |
| 5945 | /* NAPI wants this */ |
| 5946 | INIT_LIST_HEAD(&dev->napi_list); |
| 5947 | |
| 5948 | /* a dummy interface is started by default */ |
| 5949 | set_bit(__LINK_STATE_PRESENT, &dev->state); |
| 5950 | set_bit(__LINK_STATE_START, &dev->state); |
| 5951 | |
| 5952 | /* Note : We dont allocate pcpu_refcnt for dummy devices, |
| 5953 | * because users of this 'device' dont need to change |
| 5954 | * its refcount. |
| 5955 | */ |
| 5956 | |
| 5957 | return 0; |
| 5958 | } |
| 5959 | EXPORT_SYMBOL_GPL(init_dummy_netdev); |
| 5960 | |
| 5961 | |
| 5962 | /** |
| 5963 | * register_netdev - register a network device |
| 5964 | * @dev: device to register |
| 5965 | * |
| 5966 | * Take a completed network device structure and add it to the kernel |
| 5967 | * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier |
| 5968 | * chain. 0 is returned on success. A negative errno code is returned |
| 5969 | * on a failure to set up the device, or if the name is a duplicate. |
| 5970 | * |
| 5971 | * This is a wrapper around register_netdevice that takes the rtnl semaphore |
| 5972 | * and expands the device name if you passed a format string to |
| 5973 | * alloc_netdev. |
| 5974 | */ |
| 5975 | int register_netdev(struct net_device *dev) |
| 5976 | { |
| 5977 | int err; |
| 5978 | |
| 5979 | rtnl_lock(); |
| 5980 | err = register_netdevice(dev); |
| 5981 | rtnl_unlock(); |
| 5982 | return err; |
| 5983 | } |
| 5984 | EXPORT_SYMBOL(register_netdev); |
| 5985 | |
| 5986 | int netdev_refcnt_read(const struct net_device *dev) |
| 5987 | { |
| 5988 | int i, refcnt = 0; |
| 5989 | |
| 5990 | for_each_possible_cpu(i) |
| 5991 | refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); |
| 5992 | return refcnt; |
| 5993 | } |
| 5994 | EXPORT_SYMBOL(netdev_refcnt_read); |
| 5995 | |
| 5996 | /** |
| 5997 | * netdev_wait_allrefs - wait until all references are gone. |
| 5998 | * @dev: target net_device |
| 5999 | * |
| 6000 | * This is called when unregistering network devices. |
| 6001 | * |
| 6002 | * Any protocol or device that holds a reference should register |
| 6003 | * for netdevice notification, and cleanup and put back the |
| 6004 | * reference if they receive an UNREGISTER event. |
| 6005 | * We can get stuck here if buggy protocols don't correctly |
| 6006 | * call dev_put. |
| 6007 | */ |
| 6008 | static void netdev_wait_allrefs(struct net_device *dev) |
| 6009 | { |
| 6010 | unsigned long rebroadcast_time, warning_time; |
| 6011 | int refcnt; |
| 6012 | |
| 6013 | linkwatch_forget_dev(dev); |
| 6014 | |
| 6015 | rebroadcast_time = warning_time = jiffies; |
| 6016 | refcnt = netdev_refcnt_read(dev); |
| 6017 | |
| 6018 | while (refcnt != 0) { |
| 6019 | if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { |
| 6020 | rtnl_lock(); |
| 6021 | |
| 6022 | /* Rebroadcast unregister notification */ |
| 6023 | call_netdevice_notifiers(NETDEV_UNREGISTER, dev); |
| 6024 | |
| 6025 | __rtnl_unlock(); |
| 6026 | rcu_barrier(); |
| 6027 | rtnl_lock(); |
| 6028 | |
| 6029 | call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); |
| 6030 | if (test_bit(__LINK_STATE_LINKWATCH_PENDING, |
| 6031 | &dev->state)) { |
| 6032 | /* We must not have linkwatch events |
| 6033 | * pending on unregister. If this |
| 6034 | * happens, we simply run the queue |
| 6035 | * unscheduled, resulting in a noop |
| 6036 | * for this device. |
| 6037 | */ |
| 6038 | linkwatch_run_queue(); |
| 6039 | } |
| 6040 | |
| 6041 | __rtnl_unlock(); |
| 6042 | |
| 6043 | rebroadcast_time = jiffies; |
| 6044 | } |
| 6045 | |
| 6046 | msleep(250); |
| 6047 | |
| 6048 | refcnt = netdev_refcnt_read(dev); |
| 6049 | |
| 6050 | if (time_after(jiffies, warning_time + 10 * HZ)) { |
| 6051 | pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", |
| 6052 | dev->name, refcnt); |
| 6053 | warning_time = jiffies; |
| 6054 | } |
| 6055 | } |
| 6056 | } |
| 6057 | |
| 6058 | /* The sequence is: |
| 6059 | * |
| 6060 | * rtnl_lock(); |
| 6061 | * ... |
| 6062 | * register_netdevice(x1); |
| 6063 | * register_netdevice(x2); |
| 6064 | * ... |
| 6065 | * unregister_netdevice(y1); |
| 6066 | * unregister_netdevice(y2); |
| 6067 | * ... |
| 6068 | * rtnl_unlock(); |
| 6069 | * free_netdev(y1); |
| 6070 | * free_netdev(y2); |
| 6071 | * |
| 6072 | * We are invoked by rtnl_unlock(). |
| 6073 | * This allows us to deal with problems: |
| 6074 | * 1) We can delete sysfs objects which invoke hotplug |
| 6075 | * without deadlocking with linkwatch via keventd. |
| 6076 | * 2) Since we run with the RTNL semaphore not held, we can sleep |
| 6077 | * safely in order to wait for the netdev refcnt to drop to zero. |
| 6078 | * |
| 6079 | * We must not return until all unregister events added during |
| 6080 | * the interval the lock was held have been completed. |
| 6081 | */ |
| 6082 | void netdev_run_todo(void) |
| 6083 | { |
| 6084 | struct list_head list; |
| 6085 | |
| 6086 | /* Snapshot list, allow later requests */ |
| 6087 | list_replace_init(&net_todo_list, &list); |
| 6088 | |
| 6089 | __rtnl_unlock(); |
| 6090 | |
| 6091 | |
| 6092 | /* Wait for rcu callbacks to finish before next phase */ |
| 6093 | if (!list_empty(&list)) |
| 6094 | rcu_barrier(); |
| 6095 | |
| 6096 | while (!list_empty(&list)) { |
| 6097 | struct net_device *dev |
| 6098 | = list_first_entry(&list, struct net_device, todo_list); |
| 6099 | list_del(&dev->todo_list); |
| 6100 | |
| 6101 | rtnl_lock(); |
| 6102 | call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); |
| 6103 | __rtnl_unlock(); |
| 6104 | |
| 6105 | if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { |
| 6106 | pr_err("network todo '%s' but state %d\n", |
| 6107 | dev->name, dev->reg_state); |
| 6108 | dump_stack(); |
| 6109 | continue; |
| 6110 | } |
| 6111 | |
| 6112 | dev->reg_state = NETREG_UNREGISTERED; |
| 6113 | |
| 6114 | on_each_cpu(flush_backlog, dev, 1); |
| 6115 | |
| 6116 | netdev_wait_allrefs(dev); |
| 6117 | |
| 6118 | /* paranoia */ |
| 6119 | BUG_ON(netdev_refcnt_read(dev)); |
| 6120 | WARN_ON(rcu_access_pointer(dev->ip_ptr)); |
| 6121 | WARN_ON(rcu_access_pointer(dev->ip6_ptr)); |
| 6122 | WARN_ON(dev->dn_ptr); |
| 6123 | |
| 6124 | if (dev->destructor) |
| 6125 | dev->destructor(dev); |
| 6126 | |
| 6127 | /* Report a network device has been unregistered */ |
| 6128 | rtnl_lock(); |
| 6129 | dev_net(dev)->dev_unreg_count--; |
| 6130 | __rtnl_unlock(); |
| 6131 | wake_up(&netdev_unregistering_wq); |
| 6132 | |
| 6133 | /* Free network device */ |
| 6134 | kobject_put(&dev->dev.kobj); |
| 6135 | } |
| 6136 | } |
| 6137 | |
| 6138 | /* Convert net_device_stats to rtnl_link_stats64. They have the same |
| 6139 | * fields in the same order, with only the type differing. |
| 6140 | */ |
| 6141 | void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, |
| 6142 | const struct net_device_stats *netdev_stats) |
| 6143 | { |
| 6144 | #if BITS_PER_LONG == 64 |
| 6145 | BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats)); |
| 6146 | memcpy(stats64, netdev_stats, sizeof(*stats64)); |
| 6147 | #else |
| 6148 | size_t i, n = sizeof(*stats64) / sizeof(u64); |
| 6149 | const unsigned long *src = (const unsigned long *)netdev_stats; |
| 6150 | u64 *dst = (u64 *)stats64; |
| 6151 | |
| 6152 | BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) != |
| 6153 | sizeof(*stats64) / sizeof(u64)); |
| 6154 | for (i = 0; i < n; i++) |
| 6155 | dst[i] = src[i]; |
| 6156 | #endif |
| 6157 | } |
| 6158 | EXPORT_SYMBOL(netdev_stats_to_stats64); |
| 6159 | |
| 6160 | /** |
| 6161 | * dev_get_stats - get network device statistics |
| 6162 | * @dev: device to get statistics from |
| 6163 | * @storage: place to store stats |
| 6164 | * |
| 6165 | * Get network statistics from device. Return @storage. |
| 6166 | * The device driver may provide its own method by setting |
| 6167 | * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; |
| 6168 | * otherwise the internal statistics structure is used. |
| 6169 | */ |
| 6170 | struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, |
| 6171 | struct rtnl_link_stats64 *storage) |
| 6172 | { |
| 6173 | const struct net_device_ops *ops = dev->netdev_ops; |
| 6174 | |
| 6175 | if (ops->ndo_get_stats64) { |
| 6176 | memset(storage, 0, sizeof(*storage)); |
| 6177 | ops->ndo_get_stats64(dev, storage); |
| 6178 | } else if (ops->ndo_get_stats) { |
| 6179 | netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); |
| 6180 | } else { |
| 6181 | netdev_stats_to_stats64(storage, &dev->stats); |
| 6182 | } |
| 6183 | storage->rx_dropped += atomic_long_read(&dev->rx_dropped); |
| 6184 | return storage; |
| 6185 | } |
| 6186 | EXPORT_SYMBOL(dev_get_stats); |
| 6187 | |
| 6188 | struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) |
| 6189 | { |
| 6190 | struct netdev_queue *queue = dev_ingress_queue(dev); |
| 6191 | |
| 6192 | #ifdef CONFIG_NET_CLS_ACT |
| 6193 | if (queue) |
| 6194 | return queue; |
| 6195 | queue = kzalloc(sizeof(*queue), GFP_KERNEL); |
| 6196 | if (!queue) |
| 6197 | return NULL; |
| 6198 | netdev_init_one_queue(dev, queue, NULL); |
| 6199 | queue->qdisc = &noop_qdisc; |
| 6200 | queue->qdisc_sleeping = &noop_qdisc; |
| 6201 | rcu_assign_pointer(dev->ingress_queue, queue); |
| 6202 | #endif |
| 6203 | return queue; |
| 6204 | } |
| 6205 | |
| 6206 | static const struct ethtool_ops default_ethtool_ops; |
| 6207 | |
| 6208 | void netdev_set_default_ethtool_ops(struct net_device *dev, |
| 6209 | const struct ethtool_ops *ops) |
| 6210 | { |
| 6211 | if (dev->ethtool_ops == &default_ethtool_ops) |
| 6212 | dev->ethtool_ops = ops; |
| 6213 | } |
| 6214 | EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); |
| 6215 | |
| 6216 | void netdev_freemem(struct net_device *dev) |
| 6217 | { |
| 6218 | char *addr = (char *)dev - dev->padded; |
| 6219 | |
| 6220 | if (is_vmalloc_addr(addr)) |
| 6221 | vfree(addr); |
| 6222 | else |
| 6223 | kfree(addr); |
| 6224 | } |
| 6225 | |
| 6226 | /** |
| 6227 | * alloc_netdev_mqs - allocate network device |
| 6228 | * @sizeof_priv: size of private data to allocate space for |
| 6229 | * @name: device name format string |
| 6230 | * @setup: callback to initialize device |
| 6231 | * @txqs: the number of TX subqueues to allocate |
| 6232 | * @rxqs: the number of RX subqueues to allocate |
| 6233 | * |
| 6234 | * Allocates a struct net_device with private data area for driver use |
| 6235 | * and performs basic initialization. Also allocates subquue structs |
| 6236 | * for each queue on the device. |
| 6237 | */ |
| 6238 | struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, |
| 6239 | void (*setup)(struct net_device *), |
| 6240 | unsigned int txqs, unsigned int rxqs) |
| 6241 | { |
| 6242 | struct net_device *dev; |
| 6243 | size_t alloc_size; |
| 6244 | struct net_device *p; |
| 6245 | |
| 6246 | BUG_ON(strlen(name) >= sizeof(dev->name)); |
| 6247 | |
| 6248 | if (txqs < 1) { |
| 6249 | pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); |
| 6250 | return NULL; |
| 6251 | } |
| 6252 | |
| 6253 | #ifdef CONFIG_RPS |
| 6254 | if (rxqs < 1) { |
| 6255 | pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); |
| 6256 | return NULL; |
| 6257 | } |
| 6258 | #endif |
| 6259 | |
| 6260 | alloc_size = sizeof(struct net_device); |
| 6261 | if (sizeof_priv) { |
| 6262 | /* ensure 32-byte alignment of private area */ |
| 6263 | alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); |
| 6264 | alloc_size += sizeof_priv; |
| 6265 | } |
| 6266 | /* ensure 32-byte alignment of whole construct */ |
| 6267 | alloc_size += NETDEV_ALIGN - 1; |
| 6268 | |
| 6269 | p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); |
| 6270 | if (!p) |
| 6271 | p = vzalloc(alloc_size); |
| 6272 | if (!p) |
| 6273 | return NULL; |
| 6274 | |
| 6275 | dev = PTR_ALIGN(p, NETDEV_ALIGN); |
| 6276 | dev->padded = (char *)dev - (char *)p; |
| 6277 | |
| 6278 | dev->pcpu_refcnt = alloc_percpu(int); |
| 6279 | if (!dev->pcpu_refcnt) |
| 6280 | goto free_dev; |
| 6281 | |
| 6282 | if (dev_addr_init(dev)) |
| 6283 | goto free_pcpu; |
| 6284 | |
| 6285 | dev_mc_init(dev); |
| 6286 | dev_uc_init(dev); |
| 6287 | |
| 6288 | dev_net_set(dev, &init_net); |
| 6289 | |
| 6290 | dev->gso_max_size = GSO_MAX_SIZE; |
| 6291 | dev->gso_max_segs = GSO_MAX_SEGS; |
| 6292 | |
| 6293 | INIT_LIST_HEAD(&dev->napi_list); |
| 6294 | INIT_LIST_HEAD(&dev->unreg_list); |
| 6295 | INIT_LIST_HEAD(&dev->close_list); |
| 6296 | INIT_LIST_HEAD(&dev->link_watch_list); |
| 6297 | INIT_LIST_HEAD(&dev->adj_list.upper); |
| 6298 | INIT_LIST_HEAD(&dev->adj_list.lower); |
| 6299 | INIT_LIST_HEAD(&dev->all_adj_list.upper); |
| 6300 | INIT_LIST_HEAD(&dev->all_adj_list.lower); |
| 6301 | dev->priv_flags = IFF_XMIT_DST_RELEASE; |
| 6302 | setup(dev); |
| 6303 | |
| 6304 | dev->num_tx_queues = txqs; |
| 6305 | dev->real_num_tx_queues = txqs; |
| 6306 | if (netif_alloc_netdev_queues(dev)) |
| 6307 | goto free_all; |
| 6308 | |
| 6309 | #ifdef CONFIG_RPS |
| 6310 | dev->num_rx_queues = rxqs; |
| 6311 | dev->real_num_rx_queues = rxqs; |
| 6312 | if (netif_alloc_rx_queues(dev)) |
| 6313 | goto free_all; |
| 6314 | #endif |
| 6315 | |
| 6316 | strcpy(dev->name, name); |
| 6317 | dev->group = INIT_NETDEV_GROUP; |
| 6318 | if (!dev->ethtool_ops) |
| 6319 | dev->ethtool_ops = &default_ethtool_ops; |
| 6320 | return dev; |
| 6321 | |
| 6322 | free_all: |
| 6323 | free_netdev(dev); |
| 6324 | return NULL; |
| 6325 | |
| 6326 | free_pcpu: |
| 6327 | free_percpu(dev->pcpu_refcnt); |
| 6328 | netif_free_tx_queues(dev); |
| 6329 | #ifdef CONFIG_RPS |
| 6330 | kfree(dev->_rx); |
| 6331 | #endif |
| 6332 | |
| 6333 | free_dev: |
| 6334 | netdev_freemem(dev); |
| 6335 | return NULL; |
| 6336 | } |
| 6337 | EXPORT_SYMBOL(alloc_netdev_mqs); |
| 6338 | |
| 6339 | /** |
| 6340 | * free_netdev - free network device |
| 6341 | * @dev: device |
| 6342 | * |
| 6343 | * This function does the last stage of destroying an allocated device |
| 6344 | * interface. The reference to the device object is released. |
| 6345 | * If this is the last reference then it will be freed. |
| 6346 | */ |
| 6347 | void free_netdev(struct net_device *dev) |
| 6348 | { |
| 6349 | struct napi_struct *p, *n; |
| 6350 | |
| 6351 | release_net(dev_net(dev)); |
| 6352 | |
| 6353 | netif_free_tx_queues(dev); |
| 6354 | #ifdef CONFIG_RPS |
| 6355 | kfree(dev->_rx); |
| 6356 | #endif |
| 6357 | |
| 6358 | kfree(rcu_dereference_protected(dev->ingress_queue, 1)); |
| 6359 | |
| 6360 | /* Flush device addresses */ |
| 6361 | dev_addr_flush(dev); |
| 6362 | |
| 6363 | list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) |
| 6364 | netif_napi_del(p); |
| 6365 | |
| 6366 | free_percpu(dev->pcpu_refcnt); |
| 6367 | dev->pcpu_refcnt = NULL; |
| 6368 | |
| 6369 | /* Compatibility with error handling in drivers */ |
| 6370 | if (dev->reg_state == NETREG_UNINITIALIZED) { |
| 6371 | netdev_freemem(dev); |
| 6372 | return; |
| 6373 | } |
| 6374 | |
| 6375 | BUG_ON(dev->reg_state != NETREG_UNREGISTERED); |
| 6376 | dev->reg_state = NETREG_RELEASED; |
| 6377 | |
| 6378 | /* will free via device release */ |
| 6379 | put_device(&dev->dev); |
| 6380 | } |
| 6381 | EXPORT_SYMBOL(free_netdev); |
| 6382 | |
| 6383 | /** |
| 6384 | * synchronize_net - Synchronize with packet receive processing |
| 6385 | * |
| 6386 | * Wait for packets currently being received to be done. |
| 6387 | * Does not block later packets from starting. |
| 6388 | */ |
| 6389 | void synchronize_net(void) |
| 6390 | { |
| 6391 | might_sleep(); |
| 6392 | if (rtnl_is_locked()) |
| 6393 | synchronize_rcu_expedited(); |
| 6394 | else |
| 6395 | synchronize_rcu(); |
| 6396 | } |
| 6397 | EXPORT_SYMBOL(synchronize_net); |
| 6398 | |
| 6399 | /** |
| 6400 | * unregister_netdevice_queue - remove device from the kernel |
| 6401 | * @dev: device |
| 6402 | * @head: list |
| 6403 | * |
| 6404 | * This function shuts down a device interface and removes it |
| 6405 | * from the kernel tables. |
| 6406 | * If head not NULL, device is queued to be unregistered later. |
| 6407 | * |
| 6408 | * Callers must hold the rtnl semaphore. You may want |
| 6409 | * unregister_netdev() instead of this. |
| 6410 | */ |
| 6411 | |
| 6412 | void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) |
| 6413 | { |
| 6414 | ASSERT_RTNL(); |
| 6415 | |
| 6416 | if (head) { |
| 6417 | list_move_tail(&dev->unreg_list, head); |
| 6418 | } else { |
| 6419 | rollback_registered(dev); |
| 6420 | /* Finish processing unregister after unlock */ |
| 6421 | net_set_todo(dev); |
| 6422 | } |
| 6423 | } |
| 6424 | EXPORT_SYMBOL(unregister_netdevice_queue); |
| 6425 | |
| 6426 | /** |
| 6427 | * unregister_netdevice_many - unregister many devices |
| 6428 | * @head: list of devices |
| 6429 | */ |
| 6430 | void unregister_netdevice_many(struct list_head *head) |
| 6431 | { |
| 6432 | struct net_device *dev; |
| 6433 | |
| 6434 | if (!list_empty(head)) { |
| 6435 | rollback_registered_many(head); |
| 6436 | list_for_each_entry(dev, head, unreg_list) |
| 6437 | net_set_todo(dev); |
| 6438 | } |
| 6439 | } |
| 6440 | EXPORT_SYMBOL(unregister_netdevice_many); |
| 6441 | |
| 6442 | /** |
| 6443 | * unregister_netdev - remove device from the kernel |
| 6444 | * @dev: device |
| 6445 | * |
| 6446 | * This function shuts down a device interface and removes it |
| 6447 | * from the kernel tables. |
| 6448 | * |
| 6449 | * This is just a wrapper for unregister_netdevice that takes |
| 6450 | * the rtnl semaphore. In general you want to use this and not |
| 6451 | * unregister_netdevice. |
| 6452 | */ |
| 6453 | void unregister_netdev(struct net_device *dev) |
| 6454 | { |
| 6455 | rtnl_lock(); |
| 6456 | unregister_netdevice(dev); |
| 6457 | rtnl_unlock(); |
| 6458 | } |
| 6459 | EXPORT_SYMBOL(unregister_netdev); |
| 6460 | |
| 6461 | /** |
| 6462 | * dev_change_net_namespace - move device to different nethost namespace |
| 6463 | * @dev: device |
| 6464 | * @net: network namespace |
| 6465 | * @pat: If not NULL name pattern to try if the current device name |
| 6466 | * is already taken in the destination network namespace. |
| 6467 | * |
| 6468 | * This function shuts down a device interface and moves it |
| 6469 | * to a new network namespace. On success 0 is returned, on |
| 6470 | * a failure a netagive errno code is returned. |
| 6471 | * |
| 6472 | * Callers must hold the rtnl semaphore. |
| 6473 | */ |
| 6474 | |
| 6475 | int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat) |
| 6476 | { |
| 6477 | int err; |
| 6478 | |
| 6479 | ASSERT_RTNL(); |
| 6480 | |
| 6481 | /* Don't allow namespace local devices to be moved. */ |
| 6482 | err = -EINVAL; |
| 6483 | if (dev->features & NETIF_F_NETNS_LOCAL) |
| 6484 | goto out; |
| 6485 | |
| 6486 | /* Ensure the device has been registrered */ |
| 6487 | if (dev->reg_state != NETREG_REGISTERED) |
| 6488 | goto out; |
| 6489 | |
| 6490 | /* Get out if there is nothing todo */ |
| 6491 | err = 0; |
| 6492 | if (net_eq(dev_net(dev), net)) |
| 6493 | goto out; |
| 6494 | |
| 6495 | /* Pick the destination device name, and ensure |
| 6496 | * we can use it in the destination network namespace. |
| 6497 | */ |
| 6498 | err = -EEXIST; |
| 6499 | if (__dev_get_by_name(net, dev->name)) { |
| 6500 | /* We get here if we can't use the current device name */ |
| 6501 | if (!pat) |
| 6502 | goto out; |
| 6503 | if (dev_get_valid_name(net, dev, pat) < 0) |
| 6504 | goto out; |
| 6505 | } |
| 6506 | |
| 6507 | /* |
| 6508 | * And now a mini version of register_netdevice unregister_netdevice. |
| 6509 | */ |
| 6510 | |
| 6511 | /* If device is running close it first. */ |
| 6512 | dev_close(dev); |
| 6513 | |
| 6514 | /* And unlink it from device chain */ |
| 6515 | err = -ENODEV; |
| 6516 | unlist_netdevice(dev); |
| 6517 | |
| 6518 | synchronize_net(); |
| 6519 | |
| 6520 | /* Shutdown queueing discipline. */ |
| 6521 | dev_shutdown(dev); |
| 6522 | |
| 6523 | /* Notify protocols, that we are about to destroy |
| 6524 | this device. They should clean all the things. |
| 6525 | |
| 6526 | Note that dev->reg_state stays at NETREG_REGISTERED. |
| 6527 | This is wanted because this way 8021q and macvlan know |
| 6528 | the device is just moving and can keep their slaves up. |
| 6529 | */ |
| 6530 | call_netdevice_notifiers(NETDEV_UNREGISTER, dev); |
| 6531 | rcu_barrier(); |
| 6532 | call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); |
| 6533 | rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL); |
| 6534 | |
| 6535 | /* |
| 6536 | * Flush the unicast and multicast chains |
| 6537 | */ |
| 6538 | dev_uc_flush(dev); |
| 6539 | dev_mc_flush(dev); |
| 6540 | |
| 6541 | /* Send a netdev-removed uevent to the old namespace */ |
| 6542 | kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); |
| 6543 | |
| 6544 | /* Actually switch the network namespace */ |
| 6545 | dev_net_set(dev, net); |
| 6546 | |
| 6547 | /* If there is an ifindex conflict assign a new one */ |
| 6548 | if (__dev_get_by_index(net, dev->ifindex)) { |
| 6549 | int iflink = (dev->iflink == dev->ifindex); |
| 6550 | dev->ifindex = dev_new_index(net); |
| 6551 | if (iflink) |
| 6552 | dev->iflink = dev->ifindex; |
| 6553 | } |
| 6554 | |
| 6555 | /* Send a netdev-add uevent to the new namespace */ |
| 6556 | kobject_uevent(&dev->dev.kobj, KOBJ_ADD); |
| 6557 | |
| 6558 | /* Fixup kobjects */ |
| 6559 | err = device_rename(&dev->dev, dev->name); |
| 6560 | WARN_ON(err); |
| 6561 | |
| 6562 | /* Add the device back in the hashes */ |
| 6563 | list_netdevice(dev); |
| 6564 | |
| 6565 | /* Notify protocols, that a new device appeared. */ |
| 6566 | call_netdevice_notifiers(NETDEV_REGISTER, dev); |
| 6567 | |
| 6568 | /* |
| 6569 | * Prevent userspace races by waiting until the network |
| 6570 | * device is fully setup before sending notifications. |
| 6571 | */ |
| 6572 | rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); |
| 6573 | |
| 6574 | synchronize_net(); |
| 6575 | err = 0; |
| 6576 | out: |
| 6577 | return err; |
| 6578 | } |
| 6579 | EXPORT_SYMBOL_GPL(dev_change_net_namespace); |
| 6580 | |
| 6581 | static int dev_cpu_callback(struct notifier_block *nfb, |
| 6582 | unsigned long action, |
| 6583 | void *ocpu) |
| 6584 | { |
| 6585 | struct sk_buff **list_skb; |
| 6586 | struct sk_buff *skb; |
| 6587 | unsigned int cpu, oldcpu = (unsigned long)ocpu; |
| 6588 | struct softnet_data *sd, *oldsd; |
| 6589 | |
| 6590 | if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) |
| 6591 | return NOTIFY_OK; |
| 6592 | |
| 6593 | local_irq_disable(); |
| 6594 | cpu = smp_processor_id(); |
| 6595 | sd = &per_cpu(softnet_data, cpu); |
| 6596 | oldsd = &per_cpu(softnet_data, oldcpu); |
| 6597 | |
| 6598 | /* Find end of our completion_queue. */ |
| 6599 | list_skb = &sd->completion_queue; |
| 6600 | while (*list_skb) |
| 6601 | list_skb = &(*list_skb)->next; |
| 6602 | /* Append completion queue from offline CPU. */ |
| 6603 | *list_skb = oldsd->completion_queue; |
| 6604 | oldsd->completion_queue = NULL; |
| 6605 | |
| 6606 | /* Append output queue from offline CPU. */ |
| 6607 | if (oldsd->output_queue) { |
| 6608 | *sd->output_queue_tailp = oldsd->output_queue; |
| 6609 | sd->output_queue_tailp = oldsd->output_queue_tailp; |
| 6610 | oldsd->output_queue = NULL; |
| 6611 | oldsd->output_queue_tailp = &oldsd->output_queue; |
| 6612 | } |
| 6613 | /* Append NAPI poll list from offline CPU. */ |
| 6614 | if (!list_empty(&oldsd->poll_list)) { |
| 6615 | list_splice_init(&oldsd->poll_list, &sd->poll_list); |
| 6616 | raise_softirq_irqoff(NET_RX_SOFTIRQ); |
| 6617 | } |
| 6618 | |
| 6619 | raise_softirq_irqoff(NET_TX_SOFTIRQ); |
| 6620 | local_irq_enable(); |
| 6621 | |
| 6622 | /* Process offline CPU's input_pkt_queue */ |
| 6623 | while ((skb = __skb_dequeue(&oldsd->process_queue))) { |
| 6624 | netif_rx(skb); |
| 6625 | input_queue_head_incr(oldsd); |
| 6626 | } |
| 6627 | while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) { |
| 6628 | netif_rx(skb); |
| 6629 | input_queue_head_incr(oldsd); |
| 6630 | } |
| 6631 | |
| 6632 | return NOTIFY_OK; |
| 6633 | } |
| 6634 | |
| 6635 | |
| 6636 | /** |
| 6637 | * netdev_increment_features - increment feature set by one |
| 6638 | * @all: current feature set |
| 6639 | * @one: new feature set |
| 6640 | * @mask: mask feature set |
| 6641 | * |
| 6642 | * Computes a new feature set after adding a device with feature set |
| 6643 | * @one to the master device with current feature set @all. Will not |
| 6644 | * enable anything that is off in @mask. Returns the new feature set. |
| 6645 | */ |
| 6646 | netdev_features_t netdev_increment_features(netdev_features_t all, |
| 6647 | netdev_features_t one, netdev_features_t mask) |
| 6648 | { |
| 6649 | if (mask & NETIF_F_GEN_CSUM) |
| 6650 | mask |= NETIF_F_ALL_CSUM; |
| 6651 | mask |= NETIF_F_VLAN_CHALLENGED; |
| 6652 | |
| 6653 | all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask; |
| 6654 | all &= one | ~NETIF_F_ALL_FOR_ALL; |
| 6655 | |
| 6656 | /* If one device supports hw checksumming, set for all. */ |
| 6657 | if (all & NETIF_F_GEN_CSUM) |
| 6658 | all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); |
| 6659 | |
| 6660 | return all; |
| 6661 | } |
| 6662 | EXPORT_SYMBOL(netdev_increment_features); |
| 6663 | |
| 6664 | static struct hlist_head * __net_init netdev_create_hash(void) |
| 6665 | { |
| 6666 | int i; |
| 6667 | struct hlist_head *hash; |
| 6668 | |
| 6669 | hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL); |
| 6670 | if (hash != NULL) |
| 6671 | for (i = 0; i < NETDEV_HASHENTRIES; i++) |
| 6672 | INIT_HLIST_HEAD(&hash[i]); |
| 6673 | |
| 6674 | return hash; |
| 6675 | } |
| 6676 | |
| 6677 | /* Initialize per network namespace state */ |
| 6678 | static int __net_init netdev_init(struct net *net) |
| 6679 | { |
| 6680 | if (net != &init_net) |
| 6681 | INIT_LIST_HEAD(&net->dev_base_head); |
| 6682 | |
| 6683 | net->dev_name_head = netdev_create_hash(); |
| 6684 | if (net->dev_name_head == NULL) |
| 6685 | goto err_name; |
| 6686 | |
| 6687 | net->dev_index_head = netdev_create_hash(); |
| 6688 | if (net->dev_index_head == NULL) |
| 6689 | goto err_idx; |
| 6690 | |
| 6691 | return 0; |
| 6692 | |
| 6693 | err_idx: |
| 6694 | kfree(net->dev_name_head); |
| 6695 | err_name: |
| 6696 | return -ENOMEM; |
| 6697 | } |
| 6698 | |
| 6699 | /** |
| 6700 | * netdev_drivername - network driver for the device |
| 6701 | * @dev: network device |
| 6702 | * |
| 6703 | * Determine network driver for device. |
| 6704 | */ |
| 6705 | const char *netdev_drivername(const struct net_device *dev) |
| 6706 | { |
| 6707 | const struct device_driver *driver; |
| 6708 | const struct device *parent; |
| 6709 | const char *empty = ""; |
| 6710 | |
| 6711 | parent = dev->dev.parent; |
| 6712 | if (!parent) |
| 6713 | return empty; |
| 6714 | |
| 6715 | driver = parent->driver; |
| 6716 | if (driver && driver->name) |
| 6717 | return driver->name; |
| 6718 | return empty; |
| 6719 | } |
| 6720 | |
| 6721 | static int __netdev_printk(const char *level, const struct net_device *dev, |
| 6722 | struct va_format *vaf) |
| 6723 | { |
| 6724 | int r; |
| 6725 | |
| 6726 | if (dev && dev->dev.parent) { |
| 6727 | r = dev_printk_emit(level[1] - '0', |
| 6728 | dev->dev.parent, |
| 6729 | "%s %s %s: %pV", |
| 6730 | dev_driver_string(dev->dev.parent), |
| 6731 | dev_name(dev->dev.parent), |
| 6732 | netdev_name(dev), vaf); |
| 6733 | } else if (dev) { |
| 6734 | r = printk("%s%s: %pV", level, netdev_name(dev), vaf); |
| 6735 | } else { |
| 6736 | r = printk("%s(NULL net_device): %pV", level, vaf); |
| 6737 | } |
| 6738 | |
| 6739 | return r; |
| 6740 | } |
| 6741 | |
| 6742 | int netdev_printk(const char *level, const struct net_device *dev, |
| 6743 | const char *format, ...) |
| 6744 | { |
| 6745 | struct va_format vaf; |
| 6746 | va_list args; |
| 6747 | int r; |
| 6748 | |
| 6749 | va_start(args, format); |
| 6750 | |
| 6751 | vaf.fmt = format; |
| 6752 | vaf.va = &args; |
| 6753 | |
| 6754 | r = __netdev_printk(level, dev, &vaf); |
| 6755 | |
| 6756 | va_end(args); |
| 6757 | |
| 6758 | return r; |
| 6759 | } |
| 6760 | EXPORT_SYMBOL(netdev_printk); |
| 6761 | |
| 6762 | #define define_netdev_printk_level(func, level) \ |
| 6763 | int func(const struct net_device *dev, const char *fmt, ...) \ |
| 6764 | { \ |
| 6765 | int r; \ |
| 6766 | struct va_format vaf; \ |
| 6767 | va_list args; \ |
| 6768 | \ |
| 6769 | va_start(args, fmt); \ |
| 6770 | \ |
| 6771 | vaf.fmt = fmt; \ |
| 6772 | vaf.va = &args; \ |
| 6773 | \ |
| 6774 | r = __netdev_printk(level, dev, &vaf); \ |
| 6775 | \ |
| 6776 | va_end(args); \ |
| 6777 | \ |
| 6778 | return r; \ |
| 6779 | } \ |
| 6780 | EXPORT_SYMBOL(func); |
| 6781 | |
| 6782 | define_netdev_printk_level(netdev_emerg, KERN_EMERG); |
| 6783 | define_netdev_printk_level(netdev_alert, KERN_ALERT); |
| 6784 | define_netdev_printk_level(netdev_crit, KERN_CRIT); |
| 6785 | define_netdev_printk_level(netdev_err, KERN_ERR); |
| 6786 | define_netdev_printk_level(netdev_warn, KERN_WARNING); |
| 6787 | define_netdev_printk_level(netdev_notice, KERN_NOTICE); |
| 6788 | define_netdev_printk_level(netdev_info, KERN_INFO); |
| 6789 | |
| 6790 | static void __net_exit netdev_exit(struct net *net) |
| 6791 | { |
| 6792 | kfree(net->dev_name_head); |
| 6793 | kfree(net->dev_index_head); |
| 6794 | } |
| 6795 | |
| 6796 | static struct pernet_operations __net_initdata netdev_net_ops = { |
| 6797 | .init = netdev_init, |
| 6798 | .exit = netdev_exit, |
| 6799 | }; |
| 6800 | |
| 6801 | static void __net_exit default_device_exit(struct net *net) |
| 6802 | { |
| 6803 | struct net_device *dev, *aux; |
| 6804 | /* |
| 6805 | * Push all migratable network devices back to the |
| 6806 | * initial network namespace |
| 6807 | */ |
| 6808 | rtnl_lock(); |
| 6809 | for_each_netdev_safe(net, dev, aux) { |
| 6810 | int err; |
| 6811 | char fb_name[IFNAMSIZ]; |
| 6812 | |
| 6813 | /* Ignore unmoveable devices (i.e. loopback) */ |
| 6814 | if (dev->features & NETIF_F_NETNS_LOCAL) |
| 6815 | continue; |
| 6816 | |
| 6817 | /* Leave virtual devices for the generic cleanup */ |
| 6818 | if (dev->rtnl_link_ops) |
| 6819 | continue; |
| 6820 | |
| 6821 | /* Push remaining network devices to init_net */ |
| 6822 | snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); |
| 6823 | err = dev_change_net_namespace(dev, &init_net, fb_name); |
| 6824 | if (err) { |
| 6825 | pr_emerg("%s: failed to move %s to init_net: %d\n", |
| 6826 | __func__, dev->name, err); |
| 6827 | BUG(); |
| 6828 | } |
| 6829 | } |
| 6830 | rtnl_unlock(); |
| 6831 | } |
| 6832 | |
| 6833 | static void __net_exit rtnl_lock_unregistering(struct list_head *net_list) |
| 6834 | { |
| 6835 | /* Return with the rtnl_lock held when there are no network |
| 6836 | * devices unregistering in any network namespace in net_list. |
| 6837 | */ |
| 6838 | struct net *net; |
| 6839 | bool unregistering; |
| 6840 | DEFINE_WAIT(wait); |
| 6841 | |
| 6842 | for (;;) { |
| 6843 | prepare_to_wait(&netdev_unregistering_wq, &wait, |
| 6844 | TASK_UNINTERRUPTIBLE); |
| 6845 | unregistering = false; |
| 6846 | rtnl_lock(); |
| 6847 | list_for_each_entry(net, net_list, exit_list) { |
| 6848 | if (net->dev_unreg_count > 0) { |
| 6849 | unregistering = true; |
| 6850 | break; |
| 6851 | } |
| 6852 | } |
| 6853 | if (!unregistering) |
| 6854 | break; |
| 6855 | __rtnl_unlock(); |
| 6856 | schedule(); |
| 6857 | } |
| 6858 | finish_wait(&netdev_unregistering_wq, &wait); |
| 6859 | } |
| 6860 | |
| 6861 | static void __net_exit default_device_exit_batch(struct list_head *net_list) |
| 6862 | { |
| 6863 | /* At exit all network devices most be removed from a network |
| 6864 | * namespace. Do this in the reverse order of registration. |
| 6865 | * Do this across as many network namespaces as possible to |
| 6866 | * improve batching efficiency. |
| 6867 | */ |
| 6868 | struct net_device *dev; |
| 6869 | struct net *net; |
| 6870 | LIST_HEAD(dev_kill_list); |
| 6871 | |
| 6872 | /* To prevent network device cleanup code from dereferencing |
| 6873 | * loopback devices or network devices that have been freed |
| 6874 | * wait here for all pending unregistrations to complete, |
| 6875 | * before unregistring the loopback device and allowing the |
| 6876 | * network namespace be freed. |
| 6877 | * |
| 6878 | * The netdev todo list containing all network devices |
| 6879 | * unregistrations that happen in default_device_exit_batch |
| 6880 | * will run in the rtnl_unlock() at the end of |
| 6881 | * default_device_exit_batch. |
| 6882 | */ |
| 6883 | rtnl_lock_unregistering(net_list); |
| 6884 | list_for_each_entry(net, net_list, exit_list) { |
| 6885 | for_each_netdev_reverse(net, dev) { |
| 6886 | if (dev->rtnl_link_ops) |
| 6887 | dev->rtnl_link_ops->dellink(dev, &dev_kill_list); |
| 6888 | else |
| 6889 | unregister_netdevice_queue(dev, &dev_kill_list); |
| 6890 | } |
| 6891 | } |
| 6892 | unregister_netdevice_many(&dev_kill_list); |
| 6893 | list_del(&dev_kill_list); |
| 6894 | rtnl_unlock(); |
| 6895 | } |
| 6896 | |
| 6897 | static struct pernet_operations __net_initdata default_device_ops = { |
| 6898 | .exit = default_device_exit, |
| 6899 | .exit_batch = default_device_exit_batch, |
| 6900 | }; |
| 6901 | |
| 6902 | /* |
| 6903 | * Initialize the DEV module. At boot time this walks the device list and |
| 6904 | * unhooks any devices that fail to initialise (normally hardware not |
| 6905 | * present) and leaves us with a valid list of present and active devices. |
| 6906 | * |
| 6907 | */ |
| 6908 | |
| 6909 | /* |
| 6910 | * This is called single threaded during boot, so no need |
| 6911 | * to take the rtnl semaphore. |
| 6912 | */ |
| 6913 | static int __init net_dev_init(void) |
| 6914 | { |
| 6915 | int i, rc = -ENOMEM; |
| 6916 | |
| 6917 | BUG_ON(!dev_boot_phase); |
| 6918 | |
| 6919 | if (dev_proc_init()) |
| 6920 | goto out; |
| 6921 | |
| 6922 | if (netdev_kobject_init()) |
| 6923 | goto out; |
| 6924 | |
| 6925 | INIT_LIST_HEAD(&ptype_all); |
| 6926 | for (i = 0; i < PTYPE_HASH_SIZE; i++) |
| 6927 | INIT_LIST_HEAD(&ptype_base[i]); |
| 6928 | |
| 6929 | INIT_LIST_HEAD(&offload_base); |
| 6930 | |
| 6931 | if (register_pernet_subsys(&netdev_net_ops)) |
| 6932 | goto out; |
| 6933 | |
| 6934 | /* |
| 6935 | * Initialise the packet receive queues. |
| 6936 | */ |
| 6937 | |
| 6938 | for_each_possible_cpu(i) { |
| 6939 | struct softnet_data *sd = &per_cpu(softnet_data, i); |
| 6940 | |
| 6941 | memset(sd, 0, sizeof(*sd)); |
| 6942 | skb_queue_head_init(&sd->input_pkt_queue); |
| 6943 | skb_queue_head_init(&sd->process_queue); |
| 6944 | sd->completion_queue = NULL; |
| 6945 | INIT_LIST_HEAD(&sd->poll_list); |
| 6946 | sd->output_queue = NULL; |
| 6947 | sd->output_queue_tailp = &sd->output_queue; |
| 6948 | #ifdef CONFIG_RPS |
| 6949 | sd->csd.func = rps_trigger_softirq; |
| 6950 | sd->csd.info = sd; |
| 6951 | sd->csd.flags = 0; |
| 6952 | sd->cpu = i; |
| 6953 | #endif |
| 6954 | |
| 6955 | sd->backlog.poll = process_backlog; |
| 6956 | sd->backlog.weight = weight_p; |
| 6957 | sd->backlog.gro_list = NULL; |
| 6958 | sd->backlog.gro_count = 0; |
| 6959 | |
| 6960 | #ifdef CONFIG_NET_FLOW_LIMIT |
| 6961 | sd->flow_limit = NULL; |
| 6962 | #endif |
| 6963 | } |
| 6964 | |
| 6965 | dev_boot_phase = 0; |
| 6966 | |
| 6967 | /* The loopback device is special if any other network devices |
| 6968 | * is present in a network namespace the loopback device must |
| 6969 | * be present. Since we now dynamically allocate and free the |
| 6970 | * loopback device ensure this invariant is maintained by |
| 6971 | * keeping the loopback device as the first device on the |
| 6972 | * list of network devices. Ensuring the loopback devices |
| 6973 | * is the first device that appears and the last network device |
| 6974 | * that disappears. |
| 6975 | */ |
| 6976 | if (register_pernet_device(&loopback_net_ops)) |
| 6977 | goto out; |
| 6978 | |
| 6979 | if (register_pernet_device(&default_device_ops)) |
| 6980 | goto out; |
| 6981 | |
| 6982 | open_softirq(NET_TX_SOFTIRQ, net_tx_action); |
| 6983 | open_softirq(NET_RX_SOFTIRQ, net_rx_action); |
| 6984 | |
| 6985 | hotcpu_notifier(dev_cpu_callback, 0); |
| 6986 | dst_init(); |
| 6987 | rc = 0; |
| 6988 | out: |
| 6989 | return rc; |
| 6990 | } |
| 6991 | |
| 6992 | subsys_initcall(net_dev_init); |