Merge tag 'pinctrl-v3.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[deliverable/linux.git] / net / core / dev.c
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 #include <linux/errqueue.h>
136
137 #include "net-sysfs.h"
138
139 /* Instead of increasing this, you should create a hash table. */
140 #define MAX_GRO_SKBS 8
141
142 /* This should be increased if a protocol with a bigger head is added. */
143 #define GRO_MAX_HEAD (MAX_HEADER + 128)
144
145 static DEFINE_SPINLOCK(ptype_lock);
146 static DEFINE_SPINLOCK(offload_lock);
147 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
148 struct list_head ptype_all __read_mostly; /* Taps */
149 static struct list_head offload_base __read_mostly;
150
151 static int netif_rx_internal(struct sk_buff *skb);
152 static int call_netdevice_notifiers_info(unsigned long val,
153 struct net_device *dev,
154 struct netdev_notifier_info *info);
155
156 /*
157 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
158 * semaphore.
159 *
160 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
161 *
162 * Writers must hold the rtnl semaphore while they loop through the
163 * dev_base_head list, and hold dev_base_lock for writing when they do the
164 * actual updates. This allows pure readers to access the list even
165 * while a writer is preparing to update it.
166 *
167 * To put it another way, dev_base_lock is held for writing only to
168 * protect against pure readers; the rtnl semaphore provides the
169 * protection against other writers.
170 *
171 * See, for example usages, register_netdevice() and
172 * unregister_netdevice(), which must be called with the rtnl
173 * semaphore held.
174 */
175 DEFINE_RWLOCK(dev_base_lock);
176 EXPORT_SYMBOL(dev_base_lock);
177
178 /* protects napi_hash addition/deletion and napi_gen_id */
179 static DEFINE_SPINLOCK(napi_hash_lock);
180
181 static unsigned int napi_gen_id;
182 static DEFINE_HASHTABLE(napi_hash, 8);
183
184 static seqcount_t devnet_rename_seq;
185
186 static inline void dev_base_seq_inc(struct net *net)
187 {
188 while (++net->dev_base_seq == 0);
189 }
190
191 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
192 {
193 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
194
195 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
196 }
197
198 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
199 {
200 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
201 }
202
203 static inline void rps_lock(struct softnet_data *sd)
204 {
205 #ifdef CONFIG_RPS
206 spin_lock(&sd->input_pkt_queue.lock);
207 #endif
208 }
209
210 static inline void rps_unlock(struct softnet_data *sd)
211 {
212 #ifdef CONFIG_RPS
213 spin_unlock(&sd->input_pkt_queue.lock);
214 #endif
215 }
216
217 /* Device list insertion */
218 static void list_netdevice(struct net_device *dev)
219 {
220 struct net *net = dev_net(dev);
221
222 ASSERT_RTNL();
223
224 write_lock_bh(&dev_base_lock);
225 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
226 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
227 hlist_add_head_rcu(&dev->index_hlist,
228 dev_index_hash(net, dev->ifindex));
229 write_unlock_bh(&dev_base_lock);
230
231 dev_base_seq_inc(net);
232 }
233
234 /* Device list removal
235 * caller must respect a RCU grace period before freeing/reusing dev
236 */
237 static void unlist_netdevice(struct net_device *dev)
238 {
239 ASSERT_RTNL();
240
241 /* Unlink dev from the device chain */
242 write_lock_bh(&dev_base_lock);
243 list_del_rcu(&dev->dev_list);
244 hlist_del_rcu(&dev->name_hlist);
245 hlist_del_rcu(&dev->index_hlist);
246 write_unlock_bh(&dev_base_lock);
247
248 dev_base_seq_inc(dev_net(dev));
249 }
250
251 /*
252 * Our notifier list
253 */
254
255 static RAW_NOTIFIER_HEAD(netdev_chain);
256
257 /*
258 * Device drivers call our routines to queue packets here. We empty the
259 * queue in the local softnet handler.
260 */
261
262 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
263 EXPORT_PER_CPU_SYMBOL(softnet_data);
264
265 #ifdef CONFIG_LOCKDEP
266 /*
267 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
268 * according to dev->type
269 */
270 static const unsigned short netdev_lock_type[] =
271 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
272 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
273 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
274 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
275 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
276 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
277 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
278 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
279 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
280 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
281 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
282 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
283 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
284 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
285 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
286
287 static const char *const netdev_lock_name[] =
288 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
289 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
290 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
291 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
292 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
293 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
294 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
295 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
296 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
297 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
298 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
299 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
300 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
301 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
302 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
303
304 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
305 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
306
307 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
308 {
309 int i;
310
311 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
312 if (netdev_lock_type[i] == dev_type)
313 return i;
314 /* the last key is used by default */
315 return ARRAY_SIZE(netdev_lock_type) - 1;
316 }
317
318 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
319 unsigned short dev_type)
320 {
321 int i;
322
323 i = netdev_lock_pos(dev_type);
324 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
325 netdev_lock_name[i]);
326 }
327
328 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
329 {
330 int i;
331
332 i = netdev_lock_pos(dev->type);
333 lockdep_set_class_and_name(&dev->addr_list_lock,
334 &netdev_addr_lock_key[i],
335 netdev_lock_name[i]);
336 }
337 #else
338 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
339 unsigned short dev_type)
340 {
341 }
342 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
343 {
344 }
345 #endif
346
347 /*******************************************************************************
348
349 Protocol management and registration routines
350
351 *******************************************************************************/
352
353 /*
354 * Add a protocol ID to the list. Now that the input handler is
355 * smarter we can dispense with all the messy stuff that used to be
356 * here.
357 *
358 * BEWARE!!! Protocol handlers, mangling input packets,
359 * MUST BE last in hash buckets and checking protocol handlers
360 * MUST start from promiscuous ptype_all chain in net_bh.
361 * It is true now, do not change it.
362 * Explanation follows: if protocol handler, mangling packet, will
363 * be the first on list, it is not able to sense, that packet
364 * is cloned and should be copied-on-write, so that it will
365 * change it and subsequent readers will get broken packet.
366 * --ANK (980803)
367 */
368
369 static inline struct list_head *ptype_head(const struct packet_type *pt)
370 {
371 if (pt->type == htons(ETH_P_ALL))
372 return &ptype_all;
373 else
374 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
375 }
376
377 /**
378 * dev_add_pack - add packet handler
379 * @pt: packet type declaration
380 *
381 * Add a protocol handler to the networking stack. The passed &packet_type
382 * is linked into kernel lists and may not be freed until it has been
383 * removed from the kernel lists.
384 *
385 * This call does not sleep therefore it can not
386 * guarantee all CPU's that are in middle of receiving packets
387 * will see the new packet type (until the next received packet).
388 */
389
390 void dev_add_pack(struct packet_type *pt)
391 {
392 struct list_head *head = ptype_head(pt);
393
394 spin_lock(&ptype_lock);
395 list_add_rcu(&pt->list, head);
396 spin_unlock(&ptype_lock);
397 }
398 EXPORT_SYMBOL(dev_add_pack);
399
400 /**
401 * __dev_remove_pack - remove packet handler
402 * @pt: packet type declaration
403 *
404 * Remove a protocol handler that was previously added to the kernel
405 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
406 * from the kernel lists and can be freed or reused once this function
407 * returns.
408 *
409 * The packet type might still be in use by receivers
410 * and must not be freed until after all the CPU's have gone
411 * through a quiescent state.
412 */
413 void __dev_remove_pack(struct packet_type *pt)
414 {
415 struct list_head *head = ptype_head(pt);
416 struct packet_type *pt1;
417
418 spin_lock(&ptype_lock);
419
420 list_for_each_entry(pt1, head, list) {
421 if (pt == pt1) {
422 list_del_rcu(&pt->list);
423 goto out;
424 }
425 }
426
427 pr_warn("dev_remove_pack: %p not found\n", pt);
428 out:
429 spin_unlock(&ptype_lock);
430 }
431 EXPORT_SYMBOL(__dev_remove_pack);
432
433 /**
434 * dev_remove_pack - remove packet handler
435 * @pt: packet type declaration
436 *
437 * Remove a protocol handler that was previously added to the kernel
438 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
439 * from the kernel lists and can be freed or reused once this function
440 * returns.
441 *
442 * This call sleeps to guarantee that no CPU is looking at the packet
443 * type after return.
444 */
445 void dev_remove_pack(struct packet_type *pt)
446 {
447 __dev_remove_pack(pt);
448
449 synchronize_net();
450 }
451 EXPORT_SYMBOL(dev_remove_pack);
452
453
454 /**
455 * dev_add_offload - register offload handlers
456 * @po: protocol offload declaration
457 *
458 * Add protocol offload handlers to the networking stack. The passed
459 * &proto_offload is linked into kernel lists and may not be freed until
460 * it has been removed from the kernel lists.
461 *
462 * This call does not sleep therefore it can not
463 * guarantee all CPU's that are in middle of receiving packets
464 * will see the new offload handlers (until the next received packet).
465 */
466 void dev_add_offload(struct packet_offload *po)
467 {
468 struct list_head *head = &offload_base;
469
470 spin_lock(&offload_lock);
471 list_add_rcu(&po->list, head);
472 spin_unlock(&offload_lock);
473 }
474 EXPORT_SYMBOL(dev_add_offload);
475
476 /**
477 * __dev_remove_offload - remove offload handler
478 * @po: packet offload declaration
479 *
480 * Remove a protocol offload handler that was previously added to the
481 * kernel offload handlers by dev_add_offload(). The passed &offload_type
482 * is removed from the kernel lists and can be freed or reused once this
483 * function returns.
484 *
485 * The packet type might still be in use by receivers
486 * and must not be freed until after all the CPU's have gone
487 * through a quiescent state.
488 */
489 static void __dev_remove_offload(struct packet_offload *po)
490 {
491 struct list_head *head = &offload_base;
492 struct packet_offload *po1;
493
494 spin_lock(&offload_lock);
495
496 list_for_each_entry(po1, head, list) {
497 if (po == po1) {
498 list_del_rcu(&po->list);
499 goto out;
500 }
501 }
502
503 pr_warn("dev_remove_offload: %p not found\n", po);
504 out:
505 spin_unlock(&offload_lock);
506 }
507
508 /**
509 * dev_remove_offload - remove packet offload handler
510 * @po: packet offload declaration
511 *
512 * Remove a packet offload handler that was previously added to the kernel
513 * offload handlers by dev_add_offload(). The passed &offload_type is
514 * removed from the kernel lists and can be freed or reused once this
515 * function returns.
516 *
517 * This call sleeps to guarantee that no CPU is looking at the packet
518 * type after return.
519 */
520 void dev_remove_offload(struct packet_offload *po)
521 {
522 __dev_remove_offload(po);
523
524 synchronize_net();
525 }
526 EXPORT_SYMBOL(dev_remove_offload);
527
528 /******************************************************************************
529
530 Device Boot-time Settings Routines
531
532 *******************************************************************************/
533
534 /* Boot time configuration table */
535 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
536
537 /**
538 * netdev_boot_setup_add - add new setup entry
539 * @name: name of the device
540 * @map: configured settings for the device
541 *
542 * Adds new setup entry to the dev_boot_setup list. The function
543 * returns 0 on error and 1 on success. This is a generic routine to
544 * all netdevices.
545 */
546 static int netdev_boot_setup_add(char *name, struct ifmap *map)
547 {
548 struct netdev_boot_setup *s;
549 int i;
550
551 s = dev_boot_setup;
552 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
553 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
554 memset(s[i].name, 0, sizeof(s[i].name));
555 strlcpy(s[i].name, name, IFNAMSIZ);
556 memcpy(&s[i].map, map, sizeof(s[i].map));
557 break;
558 }
559 }
560
561 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
562 }
563
564 /**
565 * netdev_boot_setup_check - check boot time settings
566 * @dev: the netdevice
567 *
568 * Check boot time settings for the device.
569 * The found settings are set for the device to be used
570 * later in the device probing.
571 * Returns 0 if no settings found, 1 if they are.
572 */
573 int netdev_boot_setup_check(struct net_device *dev)
574 {
575 struct netdev_boot_setup *s = dev_boot_setup;
576 int i;
577
578 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
579 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
580 !strcmp(dev->name, s[i].name)) {
581 dev->irq = s[i].map.irq;
582 dev->base_addr = s[i].map.base_addr;
583 dev->mem_start = s[i].map.mem_start;
584 dev->mem_end = s[i].map.mem_end;
585 return 1;
586 }
587 }
588 return 0;
589 }
590 EXPORT_SYMBOL(netdev_boot_setup_check);
591
592
593 /**
594 * netdev_boot_base - get address from boot time settings
595 * @prefix: prefix for network device
596 * @unit: id for network device
597 *
598 * Check boot time settings for the base address of device.
599 * The found settings are set for the device to be used
600 * later in the device probing.
601 * Returns 0 if no settings found.
602 */
603 unsigned long netdev_boot_base(const char *prefix, int unit)
604 {
605 const struct netdev_boot_setup *s = dev_boot_setup;
606 char name[IFNAMSIZ];
607 int i;
608
609 sprintf(name, "%s%d", prefix, unit);
610
611 /*
612 * If device already registered then return base of 1
613 * to indicate not to probe for this interface
614 */
615 if (__dev_get_by_name(&init_net, name))
616 return 1;
617
618 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
619 if (!strcmp(name, s[i].name))
620 return s[i].map.base_addr;
621 return 0;
622 }
623
624 /*
625 * Saves at boot time configured settings for any netdevice.
626 */
627 int __init netdev_boot_setup(char *str)
628 {
629 int ints[5];
630 struct ifmap map;
631
632 str = get_options(str, ARRAY_SIZE(ints), ints);
633 if (!str || !*str)
634 return 0;
635
636 /* Save settings */
637 memset(&map, 0, sizeof(map));
638 if (ints[0] > 0)
639 map.irq = ints[1];
640 if (ints[0] > 1)
641 map.base_addr = ints[2];
642 if (ints[0] > 2)
643 map.mem_start = ints[3];
644 if (ints[0] > 3)
645 map.mem_end = ints[4];
646
647 /* Add new entry to the list */
648 return netdev_boot_setup_add(str, &map);
649 }
650
651 __setup("netdev=", netdev_boot_setup);
652
653 /*******************************************************************************
654
655 Device Interface Subroutines
656
657 *******************************************************************************/
658
659 /**
660 * __dev_get_by_name - find a device by its name
661 * @net: the applicable net namespace
662 * @name: name to find
663 *
664 * Find an interface by name. Must be called under RTNL semaphore
665 * or @dev_base_lock. If the name is found a pointer to the device
666 * is returned. If the name is not found then %NULL is returned. The
667 * reference counters are not incremented so the caller must be
668 * careful with locks.
669 */
670
671 struct net_device *__dev_get_by_name(struct net *net, const char *name)
672 {
673 struct net_device *dev;
674 struct hlist_head *head = dev_name_hash(net, name);
675
676 hlist_for_each_entry(dev, head, name_hlist)
677 if (!strncmp(dev->name, name, IFNAMSIZ))
678 return dev;
679
680 return NULL;
681 }
682 EXPORT_SYMBOL(__dev_get_by_name);
683
684 /**
685 * dev_get_by_name_rcu - find a device by its name
686 * @net: the applicable net namespace
687 * @name: name to find
688 *
689 * Find an interface by name.
690 * If the name is found a pointer to the device is returned.
691 * If the name is not found then %NULL is returned.
692 * The reference counters are not incremented so the caller must be
693 * careful with locks. The caller must hold RCU lock.
694 */
695
696 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
697 {
698 struct net_device *dev;
699 struct hlist_head *head = dev_name_hash(net, name);
700
701 hlist_for_each_entry_rcu(dev, head, name_hlist)
702 if (!strncmp(dev->name, name, IFNAMSIZ))
703 return dev;
704
705 return NULL;
706 }
707 EXPORT_SYMBOL(dev_get_by_name_rcu);
708
709 /**
710 * dev_get_by_name - find a device by its name
711 * @net: the applicable net namespace
712 * @name: name to find
713 *
714 * Find an interface by name. This can be called from any
715 * context and does its own locking. The returned handle has
716 * the usage count incremented and the caller must use dev_put() to
717 * release it when it is no longer needed. %NULL is returned if no
718 * matching device is found.
719 */
720
721 struct net_device *dev_get_by_name(struct net *net, const char *name)
722 {
723 struct net_device *dev;
724
725 rcu_read_lock();
726 dev = dev_get_by_name_rcu(net, name);
727 if (dev)
728 dev_hold(dev);
729 rcu_read_unlock();
730 return dev;
731 }
732 EXPORT_SYMBOL(dev_get_by_name);
733
734 /**
735 * __dev_get_by_index - find a device by its ifindex
736 * @net: the applicable net namespace
737 * @ifindex: index of device
738 *
739 * Search for an interface by index. Returns %NULL if the device
740 * is not found or a pointer to the device. The device has not
741 * had its reference counter increased so the caller must be careful
742 * about locking. The caller must hold either the RTNL semaphore
743 * or @dev_base_lock.
744 */
745
746 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
747 {
748 struct net_device *dev;
749 struct hlist_head *head = dev_index_hash(net, ifindex);
750
751 hlist_for_each_entry(dev, head, index_hlist)
752 if (dev->ifindex == ifindex)
753 return dev;
754
755 return NULL;
756 }
757 EXPORT_SYMBOL(__dev_get_by_index);
758
759 /**
760 * dev_get_by_index_rcu - find a device by its ifindex
761 * @net: the applicable net namespace
762 * @ifindex: index of device
763 *
764 * Search for an interface by index. Returns %NULL if the device
765 * is not found or a pointer to the device. The device has not
766 * had its reference counter increased so the caller must be careful
767 * about locking. The caller must hold RCU lock.
768 */
769
770 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
771 {
772 struct net_device *dev;
773 struct hlist_head *head = dev_index_hash(net, ifindex);
774
775 hlist_for_each_entry_rcu(dev, head, index_hlist)
776 if (dev->ifindex == ifindex)
777 return dev;
778
779 return NULL;
780 }
781 EXPORT_SYMBOL(dev_get_by_index_rcu);
782
783
784 /**
785 * dev_get_by_index - find a device by its ifindex
786 * @net: the applicable net namespace
787 * @ifindex: index of device
788 *
789 * Search for an interface by index. Returns NULL if the device
790 * is not found or a pointer to the device. The device returned has
791 * had a reference added and the pointer is safe until the user calls
792 * dev_put to indicate they have finished with it.
793 */
794
795 struct net_device *dev_get_by_index(struct net *net, int ifindex)
796 {
797 struct net_device *dev;
798
799 rcu_read_lock();
800 dev = dev_get_by_index_rcu(net, ifindex);
801 if (dev)
802 dev_hold(dev);
803 rcu_read_unlock();
804 return dev;
805 }
806 EXPORT_SYMBOL(dev_get_by_index);
807
808 /**
809 * netdev_get_name - get a netdevice name, knowing its ifindex.
810 * @net: network namespace
811 * @name: a pointer to the buffer where the name will be stored.
812 * @ifindex: the ifindex of the interface to get the name from.
813 *
814 * The use of raw_seqcount_begin() and cond_resched() before
815 * retrying is required as we want to give the writers a chance
816 * to complete when CONFIG_PREEMPT is not set.
817 */
818 int netdev_get_name(struct net *net, char *name, int ifindex)
819 {
820 struct net_device *dev;
821 unsigned int seq;
822
823 retry:
824 seq = raw_seqcount_begin(&devnet_rename_seq);
825 rcu_read_lock();
826 dev = dev_get_by_index_rcu(net, ifindex);
827 if (!dev) {
828 rcu_read_unlock();
829 return -ENODEV;
830 }
831
832 strcpy(name, dev->name);
833 rcu_read_unlock();
834 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
835 cond_resched();
836 goto retry;
837 }
838
839 return 0;
840 }
841
842 /**
843 * dev_getbyhwaddr_rcu - find a device by its hardware address
844 * @net: the applicable net namespace
845 * @type: media type of device
846 * @ha: hardware address
847 *
848 * Search for an interface by MAC address. Returns NULL if the device
849 * is not found or a pointer to the device.
850 * The caller must hold RCU or RTNL.
851 * The returned device has not had its ref count increased
852 * and the caller must therefore be careful about locking
853 *
854 */
855
856 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
857 const char *ha)
858 {
859 struct net_device *dev;
860
861 for_each_netdev_rcu(net, dev)
862 if (dev->type == type &&
863 !memcmp(dev->dev_addr, ha, dev->addr_len))
864 return dev;
865
866 return NULL;
867 }
868 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
869
870 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
871 {
872 struct net_device *dev;
873
874 ASSERT_RTNL();
875 for_each_netdev(net, dev)
876 if (dev->type == type)
877 return dev;
878
879 return NULL;
880 }
881 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
882
883 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
884 {
885 struct net_device *dev, *ret = NULL;
886
887 rcu_read_lock();
888 for_each_netdev_rcu(net, dev)
889 if (dev->type == type) {
890 dev_hold(dev);
891 ret = dev;
892 break;
893 }
894 rcu_read_unlock();
895 return ret;
896 }
897 EXPORT_SYMBOL(dev_getfirstbyhwtype);
898
899 /**
900 * dev_get_by_flags_rcu - find any device with given flags
901 * @net: the applicable net namespace
902 * @if_flags: IFF_* values
903 * @mask: bitmask of bits in if_flags to check
904 *
905 * Search for any interface with the given flags. Returns NULL if a device
906 * is not found or a pointer to the device. Must be called inside
907 * rcu_read_lock(), and result refcount is unchanged.
908 */
909
910 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
911 unsigned short mask)
912 {
913 struct net_device *dev, *ret;
914
915 ret = NULL;
916 for_each_netdev_rcu(net, dev) {
917 if (((dev->flags ^ if_flags) & mask) == 0) {
918 ret = dev;
919 break;
920 }
921 }
922 return ret;
923 }
924 EXPORT_SYMBOL(dev_get_by_flags_rcu);
925
926 /**
927 * dev_valid_name - check if name is okay for network device
928 * @name: name string
929 *
930 * Network device names need to be valid file names to
931 * to allow sysfs to work. We also disallow any kind of
932 * whitespace.
933 */
934 bool dev_valid_name(const char *name)
935 {
936 if (*name == '\0')
937 return false;
938 if (strlen(name) >= IFNAMSIZ)
939 return false;
940 if (!strcmp(name, ".") || !strcmp(name, ".."))
941 return false;
942
943 while (*name) {
944 if (*name == '/' || isspace(*name))
945 return false;
946 name++;
947 }
948 return true;
949 }
950 EXPORT_SYMBOL(dev_valid_name);
951
952 /**
953 * __dev_alloc_name - allocate a name for a device
954 * @net: network namespace to allocate the device name in
955 * @name: name format string
956 * @buf: scratch buffer and result name string
957 *
958 * Passed a format string - eg "lt%d" it will try and find a suitable
959 * id. It scans list of devices to build up a free map, then chooses
960 * the first empty slot. The caller must hold the dev_base or rtnl lock
961 * while allocating the name and adding the device in order to avoid
962 * duplicates.
963 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
964 * Returns the number of the unit assigned or a negative errno code.
965 */
966
967 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
968 {
969 int i = 0;
970 const char *p;
971 const int max_netdevices = 8*PAGE_SIZE;
972 unsigned long *inuse;
973 struct net_device *d;
974
975 p = strnchr(name, IFNAMSIZ-1, '%');
976 if (p) {
977 /*
978 * Verify the string as this thing may have come from
979 * the user. There must be either one "%d" and no other "%"
980 * characters.
981 */
982 if (p[1] != 'd' || strchr(p + 2, '%'))
983 return -EINVAL;
984
985 /* Use one page as a bit array of possible slots */
986 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
987 if (!inuse)
988 return -ENOMEM;
989
990 for_each_netdev(net, d) {
991 if (!sscanf(d->name, name, &i))
992 continue;
993 if (i < 0 || i >= max_netdevices)
994 continue;
995
996 /* avoid cases where sscanf is not exact inverse of printf */
997 snprintf(buf, IFNAMSIZ, name, i);
998 if (!strncmp(buf, d->name, IFNAMSIZ))
999 set_bit(i, inuse);
1000 }
1001
1002 i = find_first_zero_bit(inuse, max_netdevices);
1003 free_page((unsigned long) inuse);
1004 }
1005
1006 if (buf != name)
1007 snprintf(buf, IFNAMSIZ, name, i);
1008 if (!__dev_get_by_name(net, buf))
1009 return i;
1010
1011 /* It is possible to run out of possible slots
1012 * when the name is long and there isn't enough space left
1013 * for the digits, or if all bits are used.
1014 */
1015 return -ENFILE;
1016 }
1017
1018 /**
1019 * dev_alloc_name - allocate a name for a device
1020 * @dev: device
1021 * @name: name format string
1022 *
1023 * Passed a format string - eg "lt%d" it will try and find a suitable
1024 * id. It scans list of devices to build up a free map, then chooses
1025 * the first empty slot. The caller must hold the dev_base or rtnl lock
1026 * while allocating the name and adding the device in order to avoid
1027 * duplicates.
1028 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1029 * Returns the number of the unit assigned or a negative errno code.
1030 */
1031
1032 int dev_alloc_name(struct net_device *dev, const char *name)
1033 {
1034 char buf[IFNAMSIZ];
1035 struct net *net;
1036 int ret;
1037
1038 BUG_ON(!dev_net(dev));
1039 net = dev_net(dev);
1040 ret = __dev_alloc_name(net, name, buf);
1041 if (ret >= 0)
1042 strlcpy(dev->name, buf, IFNAMSIZ);
1043 return ret;
1044 }
1045 EXPORT_SYMBOL(dev_alloc_name);
1046
1047 static int dev_alloc_name_ns(struct net *net,
1048 struct net_device *dev,
1049 const char *name)
1050 {
1051 char buf[IFNAMSIZ];
1052 int ret;
1053
1054 ret = __dev_alloc_name(net, name, buf);
1055 if (ret >= 0)
1056 strlcpy(dev->name, buf, IFNAMSIZ);
1057 return ret;
1058 }
1059
1060 static int dev_get_valid_name(struct net *net,
1061 struct net_device *dev,
1062 const char *name)
1063 {
1064 BUG_ON(!net);
1065
1066 if (!dev_valid_name(name))
1067 return -EINVAL;
1068
1069 if (strchr(name, '%'))
1070 return dev_alloc_name_ns(net, dev, name);
1071 else if (__dev_get_by_name(net, name))
1072 return -EEXIST;
1073 else if (dev->name != name)
1074 strlcpy(dev->name, name, IFNAMSIZ);
1075
1076 return 0;
1077 }
1078
1079 /**
1080 * dev_change_name - change name of a device
1081 * @dev: device
1082 * @newname: name (or format string) must be at least IFNAMSIZ
1083 *
1084 * Change name of a device, can pass format strings "eth%d".
1085 * for wildcarding.
1086 */
1087 int dev_change_name(struct net_device *dev, const char *newname)
1088 {
1089 unsigned char old_assign_type;
1090 char oldname[IFNAMSIZ];
1091 int err = 0;
1092 int ret;
1093 struct net *net;
1094
1095 ASSERT_RTNL();
1096 BUG_ON(!dev_net(dev));
1097
1098 net = dev_net(dev);
1099 if (dev->flags & IFF_UP)
1100 return -EBUSY;
1101
1102 write_seqcount_begin(&devnet_rename_seq);
1103
1104 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1105 write_seqcount_end(&devnet_rename_seq);
1106 return 0;
1107 }
1108
1109 memcpy(oldname, dev->name, IFNAMSIZ);
1110
1111 err = dev_get_valid_name(net, dev, newname);
1112 if (err < 0) {
1113 write_seqcount_end(&devnet_rename_seq);
1114 return err;
1115 }
1116
1117 if (oldname[0] && !strchr(oldname, '%'))
1118 netdev_info(dev, "renamed from %s\n", oldname);
1119
1120 old_assign_type = dev->name_assign_type;
1121 dev->name_assign_type = NET_NAME_RENAMED;
1122
1123 rollback:
1124 ret = device_rename(&dev->dev, dev->name);
1125 if (ret) {
1126 memcpy(dev->name, oldname, IFNAMSIZ);
1127 dev->name_assign_type = old_assign_type;
1128 write_seqcount_end(&devnet_rename_seq);
1129 return ret;
1130 }
1131
1132 write_seqcount_end(&devnet_rename_seq);
1133
1134 netdev_adjacent_rename_links(dev, oldname);
1135
1136 write_lock_bh(&dev_base_lock);
1137 hlist_del_rcu(&dev->name_hlist);
1138 write_unlock_bh(&dev_base_lock);
1139
1140 synchronize_rcu();
1141
1142 write_lock_bh(&dev_base_lock);
1143 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1144 write_unlock_bh(&dev_base_lock);
1145
1146 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1147 ret = notifier_to_errno(ret);
1148
1149 if (ret) {
1150 /* err >= 0 after dev_alloc_name() or stores the first errno */
1151 if (err >= 0) {
1152 err = ret;
1153 write_seqcount_begin(&devnet_rename_seq);
1154 memcpy(dev->name, oldname, IFNAMSIZ);
1155 memcpy(oldname, newname, IFNAMSIZ);
1156 dev->name_assign_type = old_assign_type;
1157 old_assign_type = NET_NAME_RENAMED;
1158 goto rollback;
1159 } else {
1160 pr_err("%s: name change rollback failed: %d\n",
1161 dev->name, ret);
1162 }
1163 }
1164
1165 return err;
1166 }
1167
1168 /**
1169 * dev_set_alias - change ifalias of a device
1170 * @dev: device
1171 * @alias: name up to IFALIASZ
1172 * @len: limit of bytes to copy from info
1173 *
1174 * Set ifalias for a device,
1175 */
1176 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1177 {
1178 char *new_ifalias;
1179
1180 ASSERT_RTNL();
1181
1182 if (len >= IFALIASZ)
1183 return -EINVAL;
1184
1185 if (!len) {
1186 kfree(dev->ifalias);
1187 dev->ifalias = NULL;
1188 return 0;
1189 }
1190
1191 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1192 if (!new_ifalias)
1193 return -ENOMEM;
1194 dev->ifalias = new_ifalias;
1195
1196 strlcpy(dev->ifalias, alias, len+1);
1197 return len;
1198 }
1199
1200
1201 /**
1202 * netdev_features_change - device changes features
1203 * @dev: device to cause notification
1204 *
1205 * Called to indicate a device has changed features.
1206 */
1207 void netdev_features_change(struct net_device *dev)
1208 {
1209 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1210 }
1211 EXPORT_SYMBOL(netdev_features_change);
1212
1213 /**
1214 * netdev_state_change - device changes state
1215 * @dev: device to cause notification
1216 *
1217 * Called to indicate a device has changed state. This function calls
1218 * the notifier chains for netdev_chain and sends a NEWLINK message
1219 * to the routing socket.
1220 */
1221 void netdev_state_change(struct net_device *dev)
1222 {
1223 if (dev->flags & IFF_UP) {
1224 struct netdev_notifier_change_info change_info;
1225
1226 change_info.flags_changed = 0;
1227 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
1228 &change_info.info);
1229 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1230 }
1231 }
1232 EXPORT_SYMBOL(netdev_state_change);
1233
1234 /**
1235 * netdev_notify_peers - notify network peers about existence of @dev
1236 * @dev: network device
1237 *
1238 * Generate traffic such that interested network peers are aware of
1239 * @dev, such as by generating a gratuitous ARP. This may be used when
1240 * a device wants to inform the rest of the network about some sort of
1241 * reconfiguration such as a failover event or virtual machine
1242 * migration.
1243 */
1244 void netdev_notify_peers(struct net_device *dev)
1245 {
1246 rtnl_lock();
1247 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1248 rtnl_unlock();
1249 }
1250 EXPORT_SYMBOL(netdev_notify_peers);
1251
1252 static int __dev_open(struct net_device *dev)
1253 {
1254 const struct net_device_ops *ops = dev->netdev_ops;
1255 int ret;
1256
1257 ASSERT_RTNL();
1258
1259 if (!netif_device_present(dev))
1260 return -ENODEV;
1261
1262 /* Block netpoll from trying to do any rx path servicing.
1263 * If we don't do this there is a chance ndo_poll_controller
1264 * or ndo_poll may be running while we open the device
1265 */
1266 netpoll_poll_disable(dev);
1267
1268 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1269 ret = notifier_to_errno(ret);
1270 if (ret)
1271 return ret;
1272
1273 set_bit(__LINK_STATE_START, &dev->state);
1274
1275 if (ops->ndo_validate_addr)
1276 ret = ops->ndo_validate_addr(dev);
1277
1278 if (!ret && ops->ndo_open)
1279 ret = ops->ndo_open(dev);
1280
1281 netpoll_poll_enable(dev);
1282
1283 if (ret)
1284 clear_bit(__LINK_STATE_START, &dev->state);
1285 else {
1286 dev->flags |= IFF_UP;
1287 net_dmaengine_get();
1288 dev_set_rx_mode(dev);
1289 dev_activate(dev);
1290 add_device_randomness(dev->dev_addr, dev->addr_len);
1291 }
1292
1293 return ret;
1294 }
1295
1296 /**
1297 * dev_open - prepare an interface for use.
1298 * @dev: device to open
1299 *
1300 * Takes a device from down to up state. The device's private open
1301 * function is invoked and then the multicast lists are loaded. Finally
1302 * the device is moved into the up state and a %NETDEV_UP message is
1303 * sent to the netdev notifier chain.
1304 *
1305 * Calling this function on an active interface is a nop. On a failure
1306 * a negative errno code is returned.
1307 */
1308 int dev_open(struct net_device *dev)
1309 {
1310 int ret;
1311
1312 if (dev->flags & IFF_UP)
1313 return 0;
1314
1315 ret = __dev_open(dev);
1316 if (ret < 0)
1317 return ret;
1318
1319 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1320 call_netdevice_notifiers(NETDEV_UP, dev);
1321
1322 return ret;
1323 }
1324 EXPORT_SYMBOL(dev_open);
1325
1326 static int __dev_close_many(struct list_head *head)
1327 {
1328 struct net_device *dev;
1329
1330 ASSERT_RTNL();
1331 might_sleep();
1332
1333 list_for_each_entry(dev, head, close_list) {
1334 /* Temporarily disable netpoll until the interface is down */
1335 netpoll_poll_disable(dev);
1336
1337 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1338
1339 clear_bit(__LINK_STATE_START, &dev->state);
1340
1341 /* Synchronize to scheduled poll. We cannot touch poll list, it
1342 * can be even on different cpu. So just clear netif_running().
1343 *
1344 * dev->stop() will invoke napi_disable() on all of it's
1345 * napi_struct instances on this device.
1346 */
1347 smp_mb__after_atomic(); /* Commit netif_running(). */
1348 }
1349
1350 dev_deactivate_many(head);
1351
1352 list_for_each_entry(dev, head, close_list) {
1353 const struct net_device_ops *ops = dev->netdev_ops;
1354
1355 /*
1356 * Call the device specific close. This cannot fail.
1357 * Only if device is UP
1358 *
1359 * We allow it to be called even after a DETACH hot-plug
1360 * event.
1361 */
1362 if (ops->ndo_stop)
1363 ops->ndo_stop(dev);
1364
1365 dev->flags &= ~IFF_UP;
1366 net_dmaengine_put();
1367 netpoll_poll_enable(dev);
1368 }
1369
1370 return 0;
1371 }
1372
1373 static int __dev_close(struct net_device *dev)
1374 {
1375 int retval;
1376 LIST_HEAD(single);
1377
1378 list_add(&dev->close_list, &single);
1379 retval = __dev_close_many(&single);
1380 list_del(&single);
1381
1382 return retval;
1383 }
1384
1385 static int dev_close_many(struct list_head *head)
1386 {
1387 struct net_device *dev, *tmp;
1388
1389 /* Remove the devices that don't need to be closed */
1390 list_for_each_entry_safe(dev, tmp, head, close_list)
1391 if (!(dev->flags & IFF_UP))
1392 list_del_init(&dev->close_list);
1393
1394 __dev_close_many(head);
1395
1396 list_for_each_entry_safe(dev, tmp, head, close_list) {
1397 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1398 call_netdevice_notifiers(NETDEV_DOWN, dev);
1399 list_del_init(&dev->close_list);
1400 }
1401
1402 return 0;
1403 }
1404
1405 /**
1406 * dev_close - shutdown an interface.
1407 * @dev: device to shutdown
1408 *
1409 * This function moves an active device into down state. A
1410 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1411 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1412 * chain.
1413 */
1414 int dev_close(struct net_device *dev)
1415 {
1416 if (dev->flags & IFF_UP) {
1417 LIST_HEAD(single);
1418
1419 list_add(&dev->close_list, &single);
1420 dev_close_many(&single);
1421 list_del(&single);
1422 }
1423 return 0;
1424 }
1425 EXPORT_SYMBOL(dev_close);
1426
1427
1428 /**
1429 * dev_disable_lro - disable Large Receive Offload on a device
1430 * @dev: device
1431 *
1432 * Disable Large Receive Offload (LRO) on a net device. Must be
1433 * called under RTNL. This is needed if received packets may be
1434 * forwarded to another interface.
1435 */
1436 void dev_disable_lro(struct net_device *dev)
1437 {
1438 /*
1439 * If we're trying to disable lro on a vlan device
1440 * use the underlying physical device instead
1441 */
1442 if (is_vlan_dev(dev))
1443 dev = vlan_dev_real_dev(dev);
1444
1445 /* the same for macvlan devices */
1446 if (netif_is_macvlan(dev))
1447 dev = macvlan_dev_real_dev(dev);
1448
1449 dev->wanted_features &= ~NETIF_F_LRO;
1450 netdev_update_features(dev);
1451
1452 if (unlikely(dev->features & NETIF_F_LRO))
1453 netdev_WARN(dev, "failed to disable LRO!\n");
1454 }
1455 EXPORT_SYMBOL(dev_disable_lro);
1456
1457 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1458 struct net_device *dev)
1459 {
1460 struct netdev_notifier_info info;
1461
1462 netdev_notifier_info_init(&info, dev);
1463 return nb->notifier_call(nb, val, &info);
1464 }
1465
1466 static int dev_boot_phase = 1;
1467
1468 /**
1469 * register_netdevice_notifier - register a network notifier block
1470 * @nb: notifier
1471 *
1472 * Register a notifier to be called when network device events occur.
1473 * The notifier passed is linked into the kernel structures and must
1474 * not be reused until it has been unregistered. A negative errno code
1475 * is returned on a failure.
1476 *
1477 * When registered all registration and up events are replayed
1478 * to the new notifier to allow device to have a race free
1479 * view of the network device list.
1480 */
1481
1482 int register_netdevice_notifier(struct notifier_block *nb)
1483 {
1484 struct net_device *dev;
1485 struct net_device *last;
1486 struct net *net;
1487 int err;
1488
1489 rtnl_lock();
1490 err = raw_notifier_chain_register(&netdev_chain, nb);
1491 if (err)
1492 goto unlock;
1493 if (dev_boot_phase)
1494 goto unlock;
1495 for_each_net(net) {
1496 for_each_netdev(net, dev) {
1497 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1498 err = notifier_to_errno(err);
1499 if (err)
1500 goto rollback;
1501
1502 if (!(dev->flags & IFF_UP))
1503 continue;
1504
1505 call_netdevice_notifier(nb, NETDEV_UP, dev);
1506 }
1507 }
1508
1509 unlock:
1510 rtnl_unlock();
1511 return err;
1512
1513 rollback:
1514 last = dev;
1515 for_each_net(net) {
1516 for_each_netdev(net, dev) {
1517 if (dev == last)
1518 goto outroll;
1519
1520 if (dev->flags & IFF_UP) {
1521 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1522 dev);
1523 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1524 }
1525 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1526 }
1527 }
1528
1529 outroll:
1530 raw_notifier_chain_unregister(&netdev_chain, nb);
1531 goto unlock;
1532 }
1533 EXPORT_SYMBOL(register_netdevice_notifier);
1534
1535 /**
1536 * unregister_netdevice_notifier - unregister a network notifier block
1537 * @nb: notifier
1538 *
1539 * Unregister a notifier previously registered by
1540 * register_netdevice_notifier(). The notifier is unlinked into the
1541 * kernel structures and may then be reused. A negative errno code
1542 * is returned on a failure.
1543 *
1544 * After unregistering unregister and down device events are synthesized
1545 * for all devices on the device list to the removed notifier to remove
1546 * the need for special case cleanup code.
1547 */
1548
1549 int unregister_netdevice_notifier(struct notifier_block *nb)
1550 {
1551 struct net_device *dev;
1552 struct net *net;
1553 int err;
1554
1555 rtnl_lock();
1556 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1557 if (err)
1558 goto unlock;
1559
1560 for_each_net(net) {
1561 for_each_netdev(net, dev) {
1562 if (dev->flags & IFF_UP) {
1563 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1564 dev);
1565 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1566 }
1567 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1568 }
1569 }
1570 unlock:
1571 rtnl_unlock();
1572 return err;
1573 }
1574 EXPORT_SYMBOL(unregister_netdevice_notifier);
1575
1576 /**
1577 * call_netdevice_notifiers_info - call all network notifier blocks
1578 * @val: value passed unmodified to notifier function
1579 * @dev: net_device pointer passed unmodified to notifier function
1580 * @info: notifier information data
1581 *
1582 * Call all network notifier blocks. Parameters and return value
1583 * are as for raw_notifier_call_chain().
1584 */
1585
1586 static int call_netdevice_notifiers_info(unsigned long val,
1587 struct net_device *dev,
1588 struct netdev_notifier_info *info)
1589 {
1590 ASSERT_RTNL();
1591 netdev_notifier_info_init(info, dev);
1592 return raw_notifier_call_chain(&netdev_chain, val, info);
1593 }
1594
1595 /**
1596 * call_netdevice_notifiers - call all network notifier blocks
1597 * @val: value passed unmodified to notifier function
1598 * @dev: net_device pointer passed unmodified to notifier function
1599 *
1600 * Call all network notifier blocks. Parameters and return value
1601 * are as for raw_notifier_call_chain().
1602 */
1603
1604 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1605 {
1606 struct netdev_notifier_info info;
1607
1608 return call_netdevice_notifiers_info(val, dev, &info);
1609 }
1610 EXPORT_SYMBOL(call_netdevice_notifiers);
1611
1612 static struct static_key netstamp_needed __read_mostly;
1613 #ifdef HAVE_JUMP_LABEL
1614 /* We are not allowed to call static_key_slow_dec() from irq context
1615 * If net_disable_timestamp() is called from irq context, defer the
1616 * static_key_slow_dec() calls.
1617 */
1618 static atomic_t netstamp_needed_deferred;
1619 #endif
1620
1621 void net_enable_timestamp(void)
1622 {
1623 #ifdef HAVE_JUMP_LABEL
1624 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1625
1626 if (deferred) {
1627 while (--deferred)
1628 static_key_slow_dec(&netstamp_needed);
1629 return;
1630 }
1631 #endif
1632 static_key_slow_inc(&netstamp_needed);
1633 }
1634 EXPORT_SYMBOL(net_enable_timestamp);
1635
1636 void net_disable_timestamp(void)
1637 {
1638 #ifdef HAVE_JUMP_LABEL
1639 if (in_interrupt()) {
1640 atomic_inc(&netstamp_needed_deferred);
1641 return;
1642 }
1643 #endif
1644 static_key_slow_dec(&netstamp_needed);
1645 }
1646 EXPORT_SYMBOL(net_disable_timestamp);
1647
1648 static inline void net_timestamp_set(struct sk_buff *skb)
1649 {
1650 skb->tstamp.tv64 = 0;
1651 if (static_key_false(&netstamp_needed))
1652 __net_timestamp(skb);
1653 }
1654
1655 #define net_timestamp_check(COND, SKB) \
1656 if (static_key_false(&netstamp_needed)) { \
1657 if ((COND) && !(SKB)->tstamp.tv64) \
1658 __net_timestamp(SKB); \
1659 } \
1660
1661 bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
1662 {
1663 unsigned int len;
1664
1665 if (!(dev->flags & IFF_UP))
1666 return false;
1667
1668 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1669 if (skb->len <= len)
1670 return true;
1671
1672 /* if TSO is enabled, we don't care about the length as the packet
1673 * could be forwarded without being segmented before
1674 */
1675 if (skb_is_gso(skb))
1676 return true;
1677
1678 return false;
1679 }
1680 EXPORT_SYMBOL_GPL(is_skb_forwardable);
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 0;
1702 }
1703 EXPORT_SYMBOL_GPL(__dev_forward_skb);
1704
1705 /**
1706 * dev_forward_skb - loopback an skb to another netif
1707 *
1708 * @dev: destination network device
1709 * @skb: buffer to forward
1710 *
1711 * return values:
1712 * NET_RX_SUCCESS (no congestion)
1713 * NET_RX_DROP (packet was dropped, but freed)
1714 *
1715 * dev_forward_skb can be used for injecting an skb from the
1716 * start_xmit function of one device into the receive queue
1717 * of another device.
1718 *
1719 * The receiving device may be in another namespace, so
1720 * we have to clear all information in the skb that could
1721 * impact namespace isolation.
1722 */
1723 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1724 {
1725 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1726 }
1727 EXPORT_SYMBOL_GPL(dev_forward_skb);
1728
1729 static inline int deliver_skb(struct sk_buff *skb,
1730 struct packet_type *pt_prev,
1731 struct net_device *orig_dev)
1732 {
1733 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1734 return -ENOMEM;
1735 atomic_inc(&skb->users);
1736 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1737 }
1738
1739 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1740 {
1741 if (!ptype->af_packet_priv || !skb->sk)
1742 return false;
1743
1744 if (ptype->id_match)
1745 return ptype->id_match(ptype, skb->sk);
1746 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1747 return true;
1748
1749 return false;
1750 }
1751
1752 /*
1753 * Support routine. Sends outgoing frames to any network
1754 * taps currently in use.
1755 */
1756
1757 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1758 {
1759 struct packet_type *ptype;
1760 struct sk_buff *skb2 = NULL;
1761 struct packet_type *pt_prev = NULL;
1762
1763 rcu_read_lock();
1764 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1765 /* Never send packets back to the socket
1766 * they originated from - MvS (miquels@drinkel.ow.org)
1767 */
1768 if ((ptype->dev == dev || !ptype->dev) &&
1769 (!skb_loop_sk(ptype, skb))) {
1770 if (pt_prev) {
1771 deliver_skb(skb2, pt_prev, skb->dev);
1772 pt_prev = ptype;
1773 continue;
1774 }
1775
1776 skb2 = skb_clone(skb, GFP_ATOMIC);
1777 if (!skb2)
1778 break;
1779
1780 net_timestamp_set(skb2);
1781
1782 /* skb->nh should be correctly
1783 set by sender, so that the second statement is
1784 just protection against buggy protocols.
1785 */
1786 skb_reset_mac_header(skb2);
1787
1788 if (skb_network_header(skb2) < skb2->data ||
1789 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1790 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1791 ntohs(skb2->protocol),
1792 dev->name);
1793 skb_reset_network_header(skb2);
1794 }
1795
1796 skb2->transport_header = skb2->network_header;
1797 skb2->pkt_type = PACKET_OUTGOING;
1798 pt_prev = ptype;
1799 }
1800 }
1801 if (pt_prev)
1802 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1803 rcu_read_unlock();
1804 }
1805
1806 /**
1807 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1808 * @dev: Network device
1809 * @txq: number of queues available
1810 *
1811 * If real_num_tx_queues is changed the tc mappings may no longer be
1812 * valid. To resolve this verify the tc mapping remains valid and if
1813 * not NULL the mapping. With no priorities mapping to this
1814 * offset/count pair it will no longer be used. In the worst case TC0
1815 * is invalid nothing can be done so disable priority mappings. If is
1816 * expected that drivers will fix this mapping if they can before
1817 * calling netif_set_real_num_tx_queues.
1818 */
1819 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1820 {
1821 int i;
1822 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1823
1824 /* If TC0 is invalidated disable TC mapping */
1825 if (tc->offset + tc->count > txq) {
1826 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1827 dev->num_tc = 0;
1828 return;
1829 }
1830
1831 /* Invalidated prio to tc mappings set to TC0 */
1832 for (i = 1; i < TC_BITMASK + 1; i++) {
1833 int q = netdev_get_prio_tc_map(dev, i);
1834
1835 tc = &dev->tc_to_txq[q];
1836 if (tc->offset + tc->count > txq) {
1837 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1838 i, q);
1839 netdev_set_prio_tc_map(dev, i, 0);
1840 }
1841 }
1842 }
1843
1844 #ifdef CONFIG_XPS
1845 static DEFINE_MUTEX(xps_map_mutex);
1846 #define xmap_dereference(P) \
1847 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1848
1849 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1850 int cpu, u16 index)
1851 {
1852 struct xps_map *map = NULL;
1853 int pos;
1854
1855 if (dev_maps)
1856 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1857
1858 for (pos = 0; map && pos < map->len; pos++) {
1859 if (map->queues[pos] == index) {
1860 if (map->len > 1) {
1861 map->queues[pos] = map->queues[--map->len];
1862 } else {
1863 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1864 kfree_rcu(map, rcu);
1865 map = NULL;
1866 }
1867 break;
1868 }
1869 }
1870
1871 return map;
1872 }
1873
1874 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1875 {
1876 struct xps_dev_maps *dev_maps;
1877 int cpu, i;
1878 bool active = false;
1879
1880 mutex_lock(&xps_map_mutex);
1881 dev_maps = xmap_dereference(dev->xps_maps);
1882
1883 if (!dev_maps)
1884 goto out_no_maps;
1885
1886 for_each_possible_cpu(cpu) {
1887 for (i = index; i < dev->num_tx_queues; i++) {
1888 if (!remove_xps_queue(dev_maps, cpu, i))
1889 break;
1890 }
1891 if (i == dev->num_tx_queues)
1892 active = true;
1893 }
1894
1895 if (!active) {
1896 RCU_INIT_POINTER(dev->xps_maps, NULL);
1897 kfree_rcu(dev_maps, rcu);
1898 }
1899
1900 for (i = index; i < dev->num_tx_queues; i++)
1901 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1902 NUMA_NO_NODE);
1903
1904 out_no_maps:
1905 mutex_unlock(&xps_map_mutex);
1906 }
1907
1908 static struct xps_map *expand_xps_map(struct xps_map *map,
1909 int cpu, u16 index)
1910 {
1911 struct xps_map *new_map;
1912 int alloc_len = XPS_MIN_MAP_ALLOC;
1913 int i, pos;
1914
1915 for (pos = 0; map && pos < map->len; pos++) {
1916 if (map->queues[pos] != index)
1917 continue;
1918 return map;
1919 }
1920
1921 /* Need to add queue to this CPU's existing map */
1922 if (map) {
1923 if (pos < map->alloc_len)
1924 return map;
1925
1926 alloc_len = map->alloc_len * 2;
1927 }
1928
1929 /* Need to allocate new map to store queue on this CPU's map */
1930 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1931 cpu_to_node(cpu));
1932 if (!new_map)
1933 return NULL;
1934
1935 for (i = 0; i < pos; i++)
1936 new_map->queues[i] = map->queues[i];
1937 new_map->alloc_len = alloc_len;
1938 new_map->len = pos;
1939
1940 return new_map;
1941 }
1942
1943 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1944 u16 index)
1945 {
1946 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1947 struct xps_map *map, *new_map;
1948 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1949 int cpu, numa_node_id = -2;
1950 bool active = false;
1951
1952 mutex_lock(&xps_map_mutex);
1953
1954 dev_maps = xmap_dereference(dev->xps_maps);
1955
1956 /* allocate memory for queue storage */
1957 for_each_online_cpu(cpu) {
1958 if (!cpumask_test_cpu(cpu, mask))
1959 continue;
1960
1961 if (!new_dev_maps)
1962 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1963 if (!new_dev_maps) {
1964 mutex_unlock(&xps_map_mutex);
1965 return -ENOMEM;
1966 }
1967
1968 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1969 NULL;
1970
1971 map = expand_xps_map(map, cpu, index);
1972 if (!map)
1973 goto error;
1974
1975 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1976 }
1977
1978 if (!new_dev_maps)
1979 goto out_no_new_maps;
1980
1981 for_each_possible_cpu(cpu) {
1982 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1983 /* add queue to CPU maps */
1984 int pos = 0;
1985
1986 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1987 while ((pos < map->len) && (map->queues[pos] != index))
1988 pos++;
1989
1990 if (pos == map->len)
1991 map->queues[map->len++] = index;
1992 #ifdef CONFIG_NUMA
1993 if (numa_node_id == -2)
1994 numa_node_id = cpu_to_node(cpu);
1995 else if (numa_node_id != cpu_to_node(cpu))
1996 numa_node_id = -1;
1997 #endif
1998 } else if (dev_maps) {
1999 /* fill in the new device map from the old device map */
2000 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2001 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2002 }
2003
2004 }
2005
2006 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
2007
2008 /* Cleanup old maps */
2009 if (dev_maps) {
2010 for_each_possible_cpu(cpu) {
2011 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2012 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2013 if (map && map != new_map)
2014 kfree_rcu(map, rcu);
2015 }
2016
2017 kfree_rcu(dev_maps, rcu);
2018 }
2019
2020 dev_maps = new_dev_maps;
2021 active = true;
2022
2023 out_no_new_maps:
2024 /* update Tx queue numa node */
2025 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2026 (numa_node_id >= 0) ? numa_node_id :
2027 NUMA_NO_NODE);
2028
2029 if (!dev_maps)
2030 goto out_no_maps;
2031
2032 /* removes queue from unused CPUs */
2033 for_each_possible_cpu(cpu) {
2034 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2035 continue;
2036
2037 if (remove_xps_queue(dev_maps, cpu, index))
2038 active = true;
2039 }
2040
2041 /* free map if not active */
2042 if (!active) {
2043 RCU_INIT_POINTER(dev->xps_maps, NULL);
2044 kfree_rcu(dev_maps, rcu);
2045 }
2046
2047 out_no_maps:
2048 mutex_unlock(&xps_map_mutex);
2049
2050 return 0;
2051 error:
2052 /* remove any maps that we added */
2053 for_each_possible_cpu(cpu) {
2054 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2055 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2056 NULL;
2057 if (new_map && new_map != map)
2058 kfree(new_map);
2059 }
2060
2061 mutex_unlock(&xps_map_mutex);
2062
2063 kfree(new_dev_maps);
2064 return -ENOMEM;
2065 }
2066 EXPORT_SYMBOL(netif_set_xps_queue);
2067
2068 #endif
2069 /*
2070 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2071 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2072 */
2073 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2074 {
2075 int rc;
2076
2077 if (txq < 1 || txq > dev->num_tx_queues)
2078 return -EINVAL;
2079
2080 if (dev->reg_state == NETREG_REGISTERED ||
2081 dev->reg_state == NETREG_UNREGISTERING) {
2082 ASSERT_RTNL();
2083
2084 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2085 txq);
2086 if (rc)
2087 return rc;
2088
2089 if (dev->num_tc)
2090 netif_setup_tc(dev, txq);
2091
2092 if (txq < dev->real_num_tx_queues) {
2093 qdisc_reset_all_tx_gt(dev, txq);
2094 #ifdef CONFIG_XPS
2095 netif_reset_xps_queues_gt(dev, txq);
2096 #endif
2097 }
2098 }
2099
2100 dev->real_num_tx_queues = txq;
2101 return 0;
2102 }
2103 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2104
2105 #ifdef CONFIG_SYSFS
2106 /**
2107 * netif_set_real_num_rx_queues - set actual number of RX queues used
2108 * @dev: Network device
2109 * @rxq: Actual number of RX queues
2110 *
2111 * This must be called either with the rtnl_lock held or before
2112 * registration of the net device. Returns 0 on success, or a
2113 * negative error code. If called before registration, it always
2114 * succeeds.
2115 */
2116 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2117 {
2118 int rc;
2119
2120 if (rxq < 1 || rxq > dev->num_rx_queues)
2121 return -EINVAL;
2122
2123 if (dev->reg_state == NETREG_REGISTERED) {
2124 ASSERT_RTNL();
2125
2126 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2127 rxq);
2128 if (rc)
2129 return rc;
2130 }
2131
2132 dev->real_num_rx_queues = rxq;
2133 return 0;
2134 }
2135 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2136 #endif
2137
2138 /**
2139 * netif_get_num_default_rss_queues - default number of RSS queues
2140 *
2141 * This routine should set an upper limit on the number of RSS queues
2142 * used by default by multiqueue devices.
2143 */
2144 int netif_get_num_default_rss_queues(void)
2145 {
2146 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2147 }
2148 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2149
2150 static inline void __netif_reschedule(struct Qdisc *q)
2151 {
2152 struct softnet_data *sd;
2153 unsigned long flags;
2154
2155 local_irq_save(flags);
2156 sd = &__get_cpu_var(softnet_data);
2157 q->next_sched = NULL;
2158 *sd->output_queue_tailp = q;
2159 sd->output_queue_tailp = &q->next_sched;
2160 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2161 local_irq_restore(flags);
2162 }
2163
2164 void __netif_schedule(struct Qdisc *q)
2165 {
2166 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2167 __netif_reschedule(q);
2168 }
2169 EXPORT_SYMBOL(__netif_schedule);
2170
2171 struct dev_kfree_skb_cb {
2172 enum skb_free_reason reason;
2173 };
2174
2175 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2176 {
2177 return (struct dev_kfree_skb_cb *)skb->cb;
2178 }
2179
2180 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2181 {
2182 unsigned long flags;
2183
2184 if (likely(atomic_read(&skb->users) == 1)) {
2185 smp_rmb();
2186 atomic_set(&skb->users, 0);
2187 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2188 return;
2189 }
2190 get_kfree_skb_cb(skb)->reason = reason;
2191 local_irq_save(flags);
2192 skb->next = __this_cpu_read(softnet_data.completion_queue);
2193 __this_cpu_write(softnet_data.completion_queue, skb);
2194 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2195 local_irq_restore(flags);
2196 }
2197 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2198
2199 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2200 {
2201 if (in_irq() || irqs_disabled())
2202 __dev_kfree_skb_irq(skb, reason);
2203 else
2204 dev_kfree_skb(skb);
2205 }
2206 EXPORT_SYMBOL(__dev_kfree_skb_any);
2207
2208
2209 /**
2210 * netif_device_detach - mark device as removed
2211 * @dev: network device
2212 *
2213 * Mark device as removed from system and therefore no longer available.
2214 */
2215 void netif_device_detach(struct net_device *dev)
2216 {
2217 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2218 netif_running(dev)) {
2219 netif_tx_stop_all_queues(dev);
2220 }
2221 }
2222 EXPORT_SYMBOL(netif_device_detach);
2223
2224 /**
2225 * netif_device_attach - mark device as attached
2226 * @dev: network device
2227 *
2228 * Mark device as attached from system and restart if needed.
2229 */
2230 void netif_device_attach(struct net_device *dev)
2231 {
2232 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2233 netif_running(dev)) {
2234 netif_tx_wake_all_queues(dev);
2235 __netdev_watchdog_up(dev);
2236 }
2237 }
2238 EXPORT_SYMBOL(netif_device_attach);
2239
2240 static void skb_warn_bad_offload(const struct sk_buff *skb)
2241 {
2242 static const netdev_features_t null_features = 0;
2243 struct net_device *dev = skb->dev;
2244 const char *driver = "";
2245
2246 if (!net_ratelimit())
2247 return;
2248
2249 if (dev && dev->dev.parent)
2250 driver = dev_driver_string(dev->dev.parent);
2251
2252 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2253 "gso_type=%d ip_summed=%d\n",
2254 driver, dev ? &dev->features : &null_features,
2255 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2256 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2257 skb_shinfo(skb)->gso_type, skb->ip_summed);
2258 }
2259
2260 /*
2261 * Invalidate hardware checksum when packet is to be mangled, and
2262 * complete checksum manually on outgoing path.
2263 */
2264 int skb_checksum_help(struct sk_buff *skb)
2265 {
2266 __wsum csum;
2267 int ret = 0, offset;
2268
2269 if (skb->ip_summed == CHECKSUM_COMPLETE)
2270 goto out_set_summed;
2271
2272 if (unlikely(skb_shinfo(skb)->gso_size)) {
2273 skb_warn_bad_offload(skb);
2274 return -EINVAL;
2275 }
2276
2277 /* Before computing a checksum, we should make sure no frag could
2278 * be modified by an external entity : checksum could be wrong.
2279 */
2280 if (skb_has_shared_frag(skb)) {
2281 ret = __skb_linearize(skb);
2282 if (ret)
2283 goto out;
2284 }
2285
2286 offset = skb_checksum_start_offset(skb);
2287 BUG_ON(offset >= skb_headlen(skb));
2288 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2289
2290 offset += skb->csum_offset;
2291 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2292
2293 if (skb_cloned(skb) &&
2294 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2295 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2296 if (ret)
2297 goto out;
2298 }
2299
2300 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2301 out_set_summed:
2302 skb->ip_summed = CHECKSUM_NONE;
2303 out:
2304 return ret;
2305 }
2306 EXPORT_SYMBOL(skb_checksum_help);
2307
2308 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2309 {
2310 unsigned int vlan_depth = skb->mac_len;
2311 __be16 type = skb->protocol;
2312
2313 /* Tunnel gso handlers can set protocol to ethernet. */
2314 if (type == htons(ETH_P_TEB)) {
2315 struct ethhdr *eth;
2316
2317 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2318 return 0;
2319
2320 eth = (struct ethhdr *)skb_mac_header(skb);
2321 type = eth->h_proto;
2322 }
2323
2324 /* if skb->protocol is 802.1Q/AD then the header should already be
2325 * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
2326 * ETH_HLEN otherwise
2327 */
2328 if (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2329 if (vlan_depth) {
2330 if (WARN_ON(vlan_depth < VLAN_HLEN))
2331 return 0;
2332 vlan_depth -= VLAN_HLEN;
2333 } else {
2334 vlan_depth = ETH_HLEN;
2335 }
2336 do {
2337 struct vlan_hdr *vh;
2338
2339 if (unlikely(!pskb_may_pull(skb,
2340 vlan_depth + VLAN_HLEN)))
2341 return 0;
2342
2343 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2344 type = vh->h_vlan_encapsulated_proto;
2345 vlan_depth += VLAN_HLEN;
2346 } while (type == htons(ETH_P_8021Q) ||
2347 type == htons(ETH_P_8021AD));
2348 }
2349
2350 *depth = vlan_depth;
2351
2352 return type;
2353 }
2354
2355 /**
2356 * skb_mac_gso_segment - mac layer segmentation handler.
2357 * @skb: buffer to segment
2358 * @features: features for the output path (see dev->features)
2359 */
2360 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2361 netdev_features_t features)
2362 {
2363 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2364 struct packet_offload *ptype;
2365 int vlan_depth = skb->mac_len;
2366 __be16 type = skb_network_protocol(skb, &vlan_depth);
2367
2368 if (unlikely(!type))
2369 return ERR_PTR(-EINVAL);
2370
2371 __skb_pull(skb, vlan_depth);
2372
2373 rcu_read_lock();
2374 list_for_each_entry_rcu(ptype, &offload_base, list) {
2375 if (ptype->type == type && ptype->callbacks.gso_segment) {
2376 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2377 int err;
2378
2379 err = ptype->callbacks.gso_send_check(skb);
2380 segs = ERR_PTR(err);
2381 if (err || skb_gso_ok(skb, features))
2382 break;
2383 __skb_push(skb, (skb->data -
2384 skb_network_header(skb)));
2385 }
2386 segs = ptype->callbacks.gso_segment(skb, features);
2387 break;
2388 }
2389 }
2390 rcu_read_unlock();
2391
2392 __skb_push(skb, skb->data - skb_mac_header(skb));
2393
2394 return segs;
2395 }
2396 EXPORT_SYMBOL(skb_mac_gso_segment);
2397
2398
2399 /* openvswitch calls this on rx path, so we need a different check.
2400 */
2401 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2402 {
2403 if (tx_path)
2404 return skb->ip_summed != CHECKSUM_PARTIAL;
2405 else
2406 return skb->ip_summed == CHECKSUM_NONE;
2407 }
2408
2409 /**
2410 * __skb_gso_segment - Perform segmentation on skb.
2411 * @skb: buffer to segment
2412 * @features: features for the output path (see dev->features)
2413 * @tx_path: whether it is called in TX path
2414 *
2415 * This function segments the given skb and returns a list of segments.
2416 *
2417 * It may return NULL if the skb requires no segmentation. This is
2418 * only possible when GSO is used for verifying header integrity.
2419 */
2420 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2421 netdev_features_t features, bool tx_path)
2422 {
2423 if (unlikely(skb_needs_check(skb, tx_path))) {
2424 int err;
2425
2426 skb_warn_bad_offload(skb);
2427
2428 err = skb_cow_head(skb, 0);
2429 if (err < 0)
2430 return ERR_PTR(err);
2431 }
2432
2433 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2434 SKB_GSO_CB(skb)->encap_level = 0;
2435
2436 skb_reset_mac_header(skb);
2437 skb_reset_mac_len(skb);
2438
2439 return skb_mac_gso_segment(skb, features);
2440 }
2441 EXPORT_SYMBOL(__skb_gso_segment);
2442
2443 /* Take action when hardware reception checksum errors are detected. */
2444 #ifdef CONFIG_BUG
2445 void netdev_rx_csum_fault(struct net_device *dev)
2446 {
2447 if (net_ratelimit()) {
2448 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2449 dump_stack();
2450 }
2451 }
2452 EXPORT_SYMBOL(netdev_rx_csum_fault);
2453 #endif
2454
2455 /* Actually, we should eliminate this check as soon as we know, that:
2456 * 1. IOMMU is present and allows to map all the memory.
2457 * 2. No high memory really exists on this machine.
2458 */
2459
2460 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2461 {
2462 #ifdef CONFIG_HIGHMEM
2463 int i;
2464 if (!(dev->features & NETIF_F_HIGHDMA)) {
2465 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2466 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2467 if (PageHighMem(skb_frag_page(frag)))
2468 return 1;
2469 }
2470 }
2471
2472 if (PCI_DMA_BUS_IS_PHYS) {
2473 struct device *pdev = dev->dev.parent;
2474
2475 if (!pdev)
2476 return 0;
2477 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2478 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2479 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2480 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2481 return 1;
2482 }
2483 }
2484 #endif
2485 return 0;
2486 }
2487
2488 struct dev_gso_cb {
2489 void (*destructor)(struct sk_buff *skb);
2490 };
2491
2492 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2493
2494 static void dev_gso_skb_destructor(struct sk_buff *skb)
2495 {
2496 struct dev_gso_cb *cb;
2497
2498 kfree_skb_list(skb->next);
2499 skb->next = NULL;
2500
2501 cb = DEV_GSO_CB(skb);
2502 if (cb->destructor)
2503 cb->destructor(skb);
2504 }
2505
2506 /**
2507 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2508 * @skb: buffer to segment
2509 * @features: device features as applicable to this skb
2510 *
2511 * This function segments the given skb and stores the list of segments
2512 * in skb->next.
2513 */
2514 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2515 {
2516 struct sk_buff *segs;
2517
2518 segs = skb_gso_segment(skb, features);
2519
2520 /* Verifying header integrity only. */
2521 if (!segs)
2522 return 0;
2523
2524 if (IS_ERR(segs))
2525 return PTR_ERR(segs);
2526
2527 skb->next = segs;
2528 DEV_GSO_CB(skb)->destructor = skb->destructor;
2529 skb->destructor = dev_gso_skb_destructor;
2530
2531 return 0;
2532 }
2533
2534 /* If MPLS offload request, verify we are testing hardware MPLS features
2535 * instead of standard features for the netdev.
2536 */
2537 #ifdef CONFIG_NET_MPLS_GSO
2538 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2539 netdev_features_t features,
2540 __be16 type)
2541 {
2542 if (type == htons(ETH_P_MPLS_UC) || type == htons(ETH_P_MPLS_MC))
2543 features &= skb->dev->mpls_features;
2544
2545 return features;
2546 }
2547 #else
2548 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2549 netdev_features_t features,
2550 __be16 type)
2551 {
2552 return features;
2553 }
2554 #endif
2555
2556 static netdev_features_t harmonize_features(struct sk_buff *skb,
2557 netdev_features_t features)
2558 {
2559 int tmp;
2560 __be16 type;
2561
2562 type = skb_network_protocol(skb, &tmp);
2563 features = net_mpls_features(skb, features, type);
2564
2565 if (skb->ip_summed != CHECKSUM_NONE &&
2566 !can_checksum_protocol(features, type)) {
2567 features &= ~NETIF_F_ALL_CSUM;
2568 } else if (illegal_highdma(skb->dev, skb)) {
2569 features &= ~NETIF_F_SG;
2570 }
2571
2572 return features;
2573 }
2574
2575 netdev_features_t netif_skb_features(struct sk_buff *skb)
2576 {
2577 __be16 protocol = skb->protocol;
2578 netdev_features_t features = skb->dev->features;
2579
2580 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2581 features &= ~NETIF_F_GSO_MASK;
2582
2583 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2584 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2585 protocol = veh->h_vlan_encapsulated_proto;
2586 } else if (!vlan_tx_tag_present(skb)) {
2587 return harmonize_features(skb, features);
2588 }
2589
2590 features = netdev_intersect_features(features,
2591 skb->dev->vlan_features |
2592 NETIF_F_HW_VLAN_CTAG_TX |
2593 NETIF_F_HW_VLAN_STAG_TX);
2594
2595 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2596 features = netdev_intersect_features(features,
2597 NETIF_F_SG |
2598 NETIF_F_HIGHDMA |
2599 NETIF_F_FRAGLIST |
2600 NETIF_F_GEN_CSUM |
2601 NETIF_F_HW_VLAN_CTAG_TX |
2602 NETIF_F_HW_VLAN_STAG_TX);
2603
2604 return harmonize_features(skb, features);
2605 }
2606 EXPORT_SYMBOL(netif_skb_features);
2607
2608 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2609 struct netdev_queue *txq)
2610 {
2611 const struct net_device_ops *ops = dev->netdev_ops;
2612 int rc = NETDEV_TX_OK;
2613 unsigned int skb_len;
2614
2615 if (likely(!skb->next)) {
2616 netdev_features_t features;
2617
2618 /*
2619 * If device doesn't need skb->dst, release it right now while
2620 * its hot in this cpu cache
2621 */
2622 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2623 skb_dst_drop(skb);
2624
2625 features = netif_skb_features(skb);
2626
2627 if (vlan_tx_tag_present(skb) &&
2628 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2629 skb = __vlan_put_tag(skb, skb->vlan_proto,
2630 vlan_tx_tag_get(skb));
2631 if (unlikely(!skb))
2632 goto out;
2633
2634 skb->vlan_tci = 0;
2635 }
2636
2637 /* If encapsulation offload request, verify we are testing
2638 * hardware encapsulation features instead of standard
2639 * features for the netdev
2640 */
2641 if (skb->encapsulation)
2642 features &= dev->hw_enc_features;
2643
2644 if (netif_needs_gso(skb, features)) {
2645 if (unlikely(dev_gso_segment(skb, features)))
2646 goto out_kfree_skb;
2647 if (skb->next)
2648 goto gso;
2649 } else {
2650 if (skb_needs_linearize(skb, features) &&
2651 __skb_linearize(skb))
2652 goto out_kfree_skb;
2653
2654 /* If packet is not checksummed and device does not
2655 * support checksumming for this protocol, complete
2656 * checksumming here.
2657 */
2658 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2659 if (skb->encapsulation)
2660 skb_set_inner_transport_header(skb,
2661 skb_checksum_start_offset(skb));
2662 else
2663 skb_set_transport_header(skb,
2664 skb_checksum_start_offset(skb));
2665 if (!(features & NETIF_F_ALL_CSUM) &&
2666 skb_checksum_help(skb))
2667 goto out_kfree_skb;
2668 }
2669 }
2670
2671 if (!list_empty(&ptype_all))
2672 dev_queue_xmit_nit(skb, dev);
2673
2674 skb_len = skb->len;
2675 trace_net_dev_start_xmit(skb, dev);
2676 rc = ops->ndo_start_xmit(skb, dev);
2677 trace_net_dev_xmit(skb, rc, dev, skb_len);
2678 if (rc == NETDEV_TX_OK)
2679 txq_trans_update(txq);
2680 return rc;
2681 }
2682
2683 gso:
2684 do {
2685 struct sk_buff *nskb = skb->next;
2686
2687 skb->next = nskb->next;
2688 nskb->next = NULL;
2689
2690 if (!list_empty(&ptype_all))
2691 dev_queue_xmit_nit(nskb, dev);
2692
2693 skb_len = nskb->len;
2694 trace_net_dev_start_xmit(nskb, dev);
2695 rc = ops->ndo_start_xmit(nskb, dev);
2696 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2697 if (unlikely(rc != NETDEV_TX_OK)) {
2698 if (rc & ~NETDEV_TX_MASK)
2699 goto out_kfree_gso_skb;
2700 nskb->next = skb->next;
2701 skb->next = nskb;
2702 return rc;
2703 }
2704 txq_trans_update(txq);
2705 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2706 return NETDEV_TX_BUSY;
2707 } while (skb->next);
2708
2709 out_kfree_gso_skb:
2710 if (likely(skb->next == NULL)) {
2711 skb->destructor = DEV_GSO_CB(skb)->destructor;
2712 consume_skb(skb);
2713 return rc;
2714 }
2715 out_kfree_skb:
2716 kfree_skb(skb);
2717 out:
2718 return rc;
2719 }
2720 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2721
2722 static void qdisc_pkt_len_init(struct sk_buff *skb)
2723 {
2724 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2725
2726 qdisc_skb_cb(skb)->pkt_len = skb->len;
2727
2728 /* To get more precise estimation of bytes sent on wire,
2729 * we add to pkt_len the headers size of all segments
2730 */
2731 if (shinfo->gso_size) {
2732 unsigned int hdr_len;
2733 u16 gso_segs = shinfo->gso_segs;
2734
2735 /* mac layer + network layer */
2736 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2737
2738 /* + transport layer */
2739 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2740 hdr_len += tcp_hdrlen(skb);
2741 else
2742 hdr_len += sizeof(struct udphdr);
2743
2744 if (shinfo->gso_type & SKB_GSO_DODGY)
2745 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2746 shinfo->gso_size);
2747
2748 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2749 }
2750 }
2751
2752 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2753 struct net_device *dev,
2754 struct netdev_queue *txq)
2755 {
2756 spinlock_t *root_lock = qdisc_lock(q);
2757 bool contended;
2758 int rc;
2759
2760 qdisc_pkt_len_init(skb);
2761 qdisc_calculate_pkt_len(skb, q);
2762 /*
2763 * Heuristic to force contended enqueues to serialize on a
2764 * separate lock before trying to get qdisc main lock.
2765 * This permits __QDISC___STATE_RUNNING owner to get the lock more
2766 * often and dequeue packets faster.
2767 */
2768 contended = qdisc_is_running(q);
2769 if (unlikely(contended))
2770 spin_lock(&q->busylock);
2771
2772 spin_lock(root_lock);
2773 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2774 kfree_skb(skb);
2775 rc = NET_XMIT_DROP;
2776 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2777 qdisc_run_begin(q)) {
2778 /*
2779 * This is a work-conserving queue; there are no old skbs
2780 * waiting to be sent out; and the qdisc is not running -
2781 * xmit the skb directly.
2782 */
2783 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2784 skb_dst_force(skb);
2785
2786 qdisc_bstats_update(q, skb);
2787
2788 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2789 if (unlikely(contended)) {
2790 spin_unlock(&q->busylock);
2791 contended = false;
2792 }
2793 __qdisc_run(q);
2794 } else
2795 qdisc_run_end(q);
2796
2797 rc = NET_XMIT_SUCCESS;
2798 } else {
2799 skb_dst_force(skb);
2800 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2801 if (qdisc_run_begin(q)) {
2802 if (unlikely(contended)) {
2803 spin_unlock(&q->busylock);
2804 contended = false;
2805 }
2806 __qdisc_run(q);
2807 }
2808 }
2809 spin_unlock(root_lock);
2810 if (unlikely(contended))
2811 spin_unlock(&q->busylock);
2812 return rc;
2813 }
2814
2815 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2816 static void skb_update_prio(struct sk_buff *skb)
2817 {
2818 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2819
2820 if (!skb->priority && skb->sk && map) {
2821 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2822
2823 if (prioidx < map->priomap_len)
2824 skb->priority = map->priomap[prioidx];
2825 }
2826 }
2827 #else
2828 #define skb_update_prio(skb)
2829 #endif
2830
2831 static DEFINE_PER_CPU(int, xmit_recursion);
2832 #define RECURSION_LIMIT 10
2833
2834 /**
2835 * dev_loopback_xmit - loop back @skb
2836 * @skb: buffer to transmit
2837 */
2838 int dev_loopback_xmit(struct sk_buff *skb)
2839 {
2840 skb_reset_mac_header(skb);
2841 __skb_pull(skb, skb_network_offset(skb));
2842 skb->pkt_type = PACKET_LOOPBACK;
2843 skb->ip_summed = CHECKSUM_UNNECESSARY;
2844 WARN_ON(!skb_dst(skb));
2845 skb_dst_force(skb);
2846 netif_rx_ni(skb);
2847 return 0;
2848 }
2849 EXPORT_SYMBOL(dev_loopback_xmit);
2850
2851 /**
2852 * __dev_queue_xmit - transmit a buffer
2853 * @skb: buffer to transmit
2854 * @accel_priv: private data used for L2 forwarding offload
2855 *
2856 * Queue a buffer for transmission to a network device. The caller must
2857 * have set the device and priority and built the buffer before calling
2858 * this function. The function can be called from an interrupt.
2859 *
2860 * A negative errno code is returned on a failure. A success does not
2861 * guarantee the frame will be transmitted as it may be dropped due
2862 * to congestion or traffic shaping.
2863 *
2864 * -----------------------------------------------------------------------------------
2865 * I notice this method can also return errors from the queue disciplines,
2866 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2867 * be positive.
2868 *
2869 * Regardless of the return value, the skb is consumed, so it is currently
2870 * difficult to retry a send to this method. (You can bump the ref count
2871 * before sending to hold a reference for retry if you are careful.)
2872 *
2873 * When calling this method, interrupts MUST be enabled. This is because
2874 * the BH enable code must have IRQs enabled so that it will not deadlock.
2875 * --BLG
2876 */
2877 static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
2878 {
2879 struct net_device *dev = skb->dev;
2880 struct netdev_queue *txq;
2881 struct Qdisc *q;
2882 int rc = -ENOMEM;
2883
2884 skb_reset_mac_header(skb);
2885
2886 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
2887 __skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);
2888
2889 /* Disable soft irqs for various locks below. Also
2890 * stops preemption for RCU.
2891 */
2892 rcu_read_lock_bh();
2893
2894 skb_update_prio(skb);
2895
2896 txq = netdev_pick_tx(dev, skb, accel_priv);
2897 q = rcu_dereference_bh(txq->qdisc);
2898
2899 #ifdef CONFIG_NET_CLS_ACT
2900 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2901 #endif
2902 trace_net_dev_queue(skb);
2903 if (q->enqueue) {
2904 rc = __dev_xmit_skb(skb, q, dev, txq);
2905 goto out;
2906 }
2907
2908 /* The device has no queue. Common case for software devices:
2909 loopback, all the sorts of tunnels...
2910
2911 Really, it is unlikely that netif_tx_lock protection is necessary
2912 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2913 counters.)
2914 However, it is possible, that they rely on protection
2915 made by us here.
2916
2917 Check this and shot the lock. It is not prone from deadlocks.
2918 Either shot noqueue qdisc, it is even simpler 8)
2919 */
2920 if (dev->flags & IFF_UP) {
2921 int cpu = smp_processor_id(); /* ok because BHs are off */
2922
2923 if (txq->xmit_lock_owner != cpu) {
2924
2925 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2926 goto recursion_alert;
2927
2928 HARD_TX_LOCK(dev, txq, cpu);
2929
2930 if (!netif_xmit_stopped(txq)) {
2931 __this_cpu_inc(xmit_recursion);
2932 rc = dev_hard_start_xmit(skb, dev, txq);
2933 __this_cpu_dec(xmit_recursion);
2934 if (dev_xmit_complete(rc)) {
2935 HARD_TX_UNLOCK(dev, txq);
2936 goto out;
2937 }
2938 }
2939 HARD_TX_UNLOCK(dev, txq);
2940 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2941 dev->name);
2942 } else {
2943 /* Recursion is detected! It is possible,
2944 * unfortunately
2945 */
2946 recursion_alert:
2947 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2948 dev->name);
2949 }
2950 }
2951
2952 rc = -ENETDOWN;
2953 rcu_read_unlock_bh();
2954
2955 atomic_long_inc(&dev->tx_dropped);
2956 kfree_skb(skb);
2957 return rc;
2958 out:
2959 rcu_read_unlock_bh();
2960 return rc;
2961 }
2962
2963 int dev_queue_xmit(struct sk_buff *skb)
2964 {
2965 return __dev_queue_xmit(skb, NULL);
2966 }
2967 EXPORT_SYMBOL(dev_queue_xmit);
2968
2969 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2970 {
2971 return __dev_queue_xmit(skb, accel_priv);
2972 }
2973 EXPORT_SYMBOL(dev_queue_xmit_accel);
2974
2975
2976 /*=======================================================================
2977 Receiver routines
2978 =======================================================================*/
2979
2980 int netdev_max_backlog __read_mostly = 1000;
2981 EXPORT_SYMBOL(netdev_max_backlog);
2982
2983 int netdev_tstamp_prequeue __read_mostly = 1;
2984 int netdev_budget __read_mostly = 300;
2985 int weight_p __read_mostly = 64; /* old backlog weight */
2986
2987 /* Called with irq disabled */
2988 static inline void ____napi_schedule(struct softnet_data *sd,
2989 struct napi_struct *napi)
2990 {
2991 list_add_tail(&napi->poll_list, &sd->poll_list);
2992 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2993 }
2994
2995 #ifdef CONFIG_RPS
2996
2997 /* One global table that all flow-based protocols share. */
2998 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2999 EXPORT_SYMBOL(rps_sock_flow_table);
3000
3001 struct static_key rps_needed __read_mostly;
3002
3003 static struct rps_dev_flow *
3004 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3005 struct rps_dev_flow *rflow, u16 next_cpu)
3006 {
3007 if (next_cpu != RPS_NO_CPU) {
3008 #ifdef CONFIG_RFS_ACCEL
3009 struct netdev_rx_queue *rxqueue;
3010 struct rps_dev_flow_table *flow_table;
3011 struct rps_dev_flow *old_rflow;
3012 u32 flow_id;
3013 u16 rxq_index;
3014 int rc;
3015
3016 /* Should we steer this flow to a different hardware queue? */
3017 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
3018 !(dev->features & NETIF_F_NTUPLE))
3019 goto out;
3020 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
3021 if (rxq_index == skb_get_rx_queue(skb))
3022 goto out;
3023
3024 rxqueue = dev->_rx + rxq_index;
3025 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3026 if (!flow_table)
3027 goto out;
3028 flow_id = skb_get_hash(skb) & flow_table->mask;
3029 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
3030 rxq_index, flow_id);
3031 if (rc < 0)
3032 goto out;
3033 old_rflow = rflow;
3034 rflow = &flow_table->flows[flow_id];
3035 rflow->filter = rc;
3036 if (old_rflow->filter == rflow->filter)
3037 old_rflow->filter = RPS_NO_FILTER;
3038 out:
3039 #endif
3040 rflow->last_qtail =
3041 per_cpu(softnet_data, next_cpu).input_queue_head;
3042 }
3043
3044 rflow->cpu = next_cpu;
3045 return rflow;
3046 }
3047
3048 /*
3049 * get_rps_cpu is called from netif_receive_skb and returns the target
3050 * CPU from the RPS map of the receiving queue for a given skb.
3051 * rcu_read_lock must be held on entry.
3052 */
3053 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3054 struct rps_dev_flow **rflowp)
3055 {
3056 struct netdev_rx_queue *rxqueue;
3057 struct rps_map *map;
3058 struct rps_dev_flow_table *flow_table;
3059 struct rps_sock_flow_table *sock_flow_table;
3060 int cpu = -1;
3061 u16 tcpu;
3062 u32 hash;
3063
3064 if (skb_rx_queue_recorded(skb)) {
3065 u16 index = skb_get_rx_queue(skb);
3066 if (unlikely(index >= dev->real_num_rx_queues)) {
3067 WARN_ONCE(dev->real_num_rx_queues > 1,
3068 "%s received packet on queue %u, but number "
3069 "of RX queues is %u\n",
3070 dev->name, index, dev->real_num_rx_queues);
3071 goto done;
3072 }
3073 rxqueue = dev->_rx + index;
3074 } else
3075 rxqueue = dev->_rx;
3076
3077 map = rcu_dereference(rxqueue->rps_map);
3078 if (map) {
3079 if (map->len == 1 &&
3080 !rcu_access_pointer(rxqueue->rps_flow_table)) {
3081 tcpu = map->cpus[0];
3082 if (cpu_online(tcpu))
3083 cpu = tcpu;
3084 goto done;
3085 }
3086 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3087 goto done;
3088 }
3089
3090 skb_reset_network_header(skb);
3091 hash = skb_get_hash(skb);
3092 if (!hash)
3093 goto done;
3094
3095 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3096 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3097 if (flow_table && sock_flow_table) {
3098 u16 next_cpu;
3099 struct rps_dev_flow *rflow;
3100
3101 rflow = &flow_table->flows[hash & flow_table->mask];
3102 tcpu = rflow->cpu;
3103
3104 next_cpu = sock_flow_table->ents[hash & sock_flow_table->mask];
3105
3106 /*
3107 * If the desired CPU (where last recvmsg was done) is
3108 * different from current CPU (one in the rx-queue flow
3109 * table entry), switch if one of the following holds:
3110 * - Current CPU is unset (equal to RPS_NO_CPU).
3111 * - Current CPU is offline.
3112 * - The current CPU's queue tail has advanced beyond the
3113 * last packet that was enqueued using this table entry.
3114 * This guarantees that all previous packets for the flow
3115 * have been dequeued, thus preserving in order delivery.
3116 */
3117 if (unlikely(tcpu != next_cpu) &&
3118 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3119 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3120 rflow->last_qtail)) >= 0)) {
3121 tcpu = next_cpu;
3122 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3123 }
3124
3125 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3126 *rflowp = rflow;
3127 cpu = tcpu;
3128 goto done;
3129 }
3130 }
3131
3132 if (map) {
3133 tcpu = map->cpus[((u64) hash * map->len) >> 32];
3134
3135 if (cpu_online(tcpu)) {
3136 cpu = tcpu;
3137 goto done;
3138 }
3139 }
3140
3141 done:
3142 return cpu;
3143 }
3144
3145 #ifdef CONFIG_RFS_ACCEL
3146
3147 /**
3148 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3149 * @dev: Device on which the filter was set
3150 * @rxq_index: RX queue index
3151 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3152 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3153 *
3154 * Drivers that implement ndo_rx_flow_steer() should periodically call
3155 * this function for each installed filter and remove the filters for
3156 * which it returns %true.
3157 */
3158 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3159 u32 flow_id, u16 filter_id)
3160 {
3161 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3162 struct rps_dev_flow_table *flow_table;
3163 struct rps_dev_flow *rflow;
3164 bool expire = true;
3165 int cpu;
3166
3167 rcu_read_lock();
3168 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3169 if (flow_table && flow_id <= flow_table->mask) {
3170 rflow = &flow_table->flows[flow_id];
3171 cpu = ACCESS_ONCE(rflow->cpu);
3172 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3173 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3174 rflow->last_qtail) <
3175 (int)(10 * flow_table->mask)))
3176 expire = false;
3177 }
3178 rcu_read_unlock();
3179 return expire;
3180 }
3181 EXPORT_SYMBOL(rps_may_expire_flow);
3182
3183 #endif /* CONFIG_RFS_ACCEL */
3184
3185 /* Called from hardirq (IPI) context */
3186 static void rps_trigger_softirq(void *data)
3187 {
3188 struct softnet_data *sd = data;
3189
3190 ____napi_schedule(sd, &sd->backlog);
3191 sd->received_rps++;
3192 }
3193
3194 #endif /* CONFIG_RPS */
3195
3196 /*
3197 * Check if this softnet_data structure is another cpu one
3198 * If yes, queue it to our IPI list and return 1
3199 * If no, return 0
3200 */
3201 static int rps_ipi_queued(struct softnet_data *sd)
3202 {
3203 #ifdef CONFIG_RPS
3204 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3205
3206 if (sd != mysd) {
3207 sd->rps_ipi_next = mysd->rps_ipi_list;
3208 mysd->rps_ipi_list = sd;
3209
3210 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3211 return 1;
3212 }
3213 #endif /* CONFIG_RPS */
3214 return 0;
3215 }
3216
3217 #ifdef CONFIG_NET_FLOW_LIMIT
3218 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3219 #endif
3220
3221 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3222 {
3223 #ifdef CONFIG_NET_FLOW_LIMIT
3224 struct sd_flow_limit *fl;
3225 struct softnet_data *sd;
3226 unsigned int old_flow, new_flow;
3227
3228 if (qlen < (netdev_max_backlog >> 1))
3229 return false;
3230
3231 sd = &__get_cpu_var(softnet_data);
3232
3233 rcu_read_lock();
3234 fl = rcu_dereference(sd->flow_limit);
3235 if (fl) {
3236 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3237 old_flow = fl->history[fl->history_head];
3238 fl->history[fl->history_head] = new_flow;
3239
3240 fl->history_head++;
3241 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3242
3243 if (likely(fl->buckets[old_flow]))
3244 fl->buckets[old_flow]--;
3245
3246 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3247 fl->count++;
3248 rcu_read_unlock();
3249 return true;
3250 }
3251 }
3252 rcu_read_unlock();
3253 #endif
3254 return false;
3255 }
3256
3257 /*
3258 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3259 * queue (may be a remote CPU queue).
3260 */
3261 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3262 unsigned int *qtail)
3263 {
3264 struct softnet_data *sd;
3265 unsigned long flags;
3266 unsigned int qlen;
3267
3268 sd = &per_cpu(softnet_data, cpu);
3269
3270 local_irq_save(flags);
3271
3272 rps_lock(sd);
3273 qlen = skb_queue_len(&sd->input_pkt_queue);
3274 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3275 if (skb_queue_len(&sd->input_pkt_queue)) {
3276 enqueue:
3277 __skb_queue_tail(&sd->input_pkt_queue, skb);
3278 input_queue_tail_incr_save(sd, qtail);
3279 rps_unlock(sd);
3280 local_irq_restore(flags);
3281 return NET_RX_SUCCESS;
3282 }
3283
3284 /* Schedule NAPI for backlog device
3285 * We can use non atomic operation since we own the queue lock
3286 */
3287 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3288 if (!rps_ipi_queued(sd))
3289 ____napi_schedule(sd, &sd->backlog);
3290 }
3291 goto enqueue;
3292 }
3293
3294 sd->dropped++;
3295 rps_unlock(sd);
3296
3297 local_irq_restore(flags);
3298
3299 atomic_long_inc(&skb->dev->rx_dropped);
3300 kfree_skb(skb);
3301 return NET_RX_DROP;
3302 }
3303
3304 static int netif_rx_internal(struct sk_buff *skb)
3305 {
3306 int ret;
3307
3308 net_timestamp_check(netdev_tstamp_prequeue, skb);
3309
3310 trace_netif_rx(skb);
3311 #ifdef CONFIG_RPS
3312 if (static_key_false(&rps_needed)) {
3313 struct rps_dev_flow voidflow, *rflow = &voidflow;
3314 int cpu;
3315
3316 preempt_disable();
3317 rcu_read_lock();
3318
3319 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3320 if (cpu < 0)
3321 cpu = smp_processor_id();
3322
3323 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3324
3325 rcu_read_unlock();
3326 preempt_enable();
3327 } else
3328 #endif
3329 {
3330 unsigned int qtail;
3331 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3332 put_cpu();
3333 }
3334 return ret;
3335 }
3336
3337 /**
3338 * netif_rx - post buffer to the network code
3339 * @skb: buffer to post
3340 *
3341 * This function receives a packet from a device driver and queues it for
3342 * the upper (protocol) levels to process. It always succeeds. The buffer
3343 * may be dropped during processing for congestion control or by the
3344 * protocol layers.
3345 *
3346 * return values:
3347 * NET_RX_SUCCESS (no congestion)
3348 * NET_RX_DROP (packet was dropped)
3349 *
3350 */
3351
3352 int netif_rx(struct sk_buff *skb)
3353 {
3354 trace_netif_rx_entry(skb);
3355
3356 return netif_rx_internal(skb);
3357 }
3358 EXPORT_SYMBOL(netif_rx);
3359
3360 int netif_rx_ni(struct sk_buff *skb)
3361 {
3362 int err;
3363
3364 trace_netif_rx_ni_entry(skb);
3365
3366 preempt_disable();
3367 err = netif_rx_internal(skb);
3368 if (local_softirq_pending())
3369 do_softirq();
3370 preempt_enable();
3371
3372 return err;
3373 }
3374 EXPORT_SYMBOL(netif_rx_ni);
3375
3376 static void net_tx_action(struct softirq_action *h)
3377 {
3378 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3379
3380 if (sd->completion_queue) {
3381 struct sk_buff *clist;
3382
3383 local_irq_disable();
3384 clist = sd->completion_queue;
3385 sd->completion_queue = NULL;
3386 local_irq_enable();
3387
3388 while (clist) {
3389 struct sk_buff *skb = clist;
3390 clist = clist->next;
3391
3392 WARN_ON(atomic_read(&skb->users));
3393 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3394 trace_consume_skb(skb);
3395 else
3396 trace_kfree_skb(skb, net_tx_action);
3397 __kfree_skb(skb);
3398 }
3399 }
3400
3401 if (sd->output_queue) {
3402 struct Qdisc *head;
3403
3404 local_irq_disable();
3405 head = sd->output_queue;
3406 sd->output_queue = NULL;
3407 sd->output_queue_tailp = &sd->output_queue;
3408 local_irq_enable();
3409
3410 while (head) {
3411 struct Qdisc *q = head;
3412 spinlock_t *root_lock;
3413
3414 head = head->next_sched;
3415
3416 root_lock = qdisc_lock(q);
3417 if (spin_trylock(root_lock)) {
3418 smp_mb__before_atomic();
3419 clear_bit(__QDISC_STATE_SCHED,
3420 &q->state);
3421 qdisc_run(q);
3422 spin_unlock(root_lock);
3423 } else {
3424 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3425 &q->state)) {
3426 __netif_reschedule(q);
3427 } else {
3428 smp_mb__before_atomic();
3429 clear_bit(__QDISC_STATE_SCHED,
3430 &q->state);
3431 }
3432 }
3433 }
3434 }
3435 }
3436
3437 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3438 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3439 /* This hook is defined here for ATM LANE */
3440 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3441 unsigned char *addr) __read_mostly;
3442 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3443 #endif
3444
3445 #ifdef CONFIG_NET_CLS_ACT
3446 /* TODO: Maybe we should just force sch_ingress to be compiled in
3447 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3448 * a compare and 2 stores extra right now if we dont have it on
3449 * but have CONFIG_NET_CLS_ACT
3450 * NOTE: This doesn't stop any functionality; if you dont have
3451 * the ingress scheduler, you just can't add policies on ingress.
3452 *
3453 */
3454 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3455 {
3456 struct net_device *dev = skb->dev;
3457 u32 ttl = G_TC_RTTL(skb->tc_verd);
3458 int result = TC_ACT_OK;
3459 struct Qdisc *q;
3460
3461 if (unlikely(MAX_RED_LOOP < ttl++)) {
3462 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3463 skb->skb_iif, dev->ifindex);
3464 return TC_ACT_SHOT;
3465 }
3466
3467 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3468 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3469
3470 q = rxq->qdisc;
3471 if (q != &noop_qdisc) {
3472 spin_lock(qdisc_lock(q));
3473 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3474 result = qdisc_enqueue_root(skb, q);
3475 spin_unlock(qdisc_lock(q));
3476 }
3477
3478 return result;
3479 }
3480
3481 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3482 struct packet_type **pt_prev,
3483 int *ret, struct net_device *orig_dev)
3484 {
3485 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3486
3487 if (!rxq || rxq->qdisc == &noop_qdisc)
3488 goto out;
3489
3490 if (*pt_prev) {
3491 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3492 *pt_prev = NULL;
3493 }
3494
3495 switch (ing_filter(skb, rxq)) {
3496 case TC_ACT_SHOT:
3497 case TC_ACT_STOLEN:
3498 kfree_skb(skb);
3499 return NULL;
3500 }
3501
3502 out:
3503 skb->tc_verd = 0;
3504 return skb;
3505 }
3506 #endif
3507
3508 /**
3509 * netdev_rx_handler_register - register receive handler
3510 * @dev: device to register a handler for
3511 * @rx_handler: receive handler to register
3512 * @rx_handler_data: data pointer that is used by rx handler
3513 *
3514 * Register a receive handler for a device. This handler will then be
3515 * called from __netif_receive_skb. A negative errno code is returned
3516 * on a failure.
3517 *
3518 * The caller must hold the rtnl_mutex.
3519 *
3520 * For a general description of rx_handler, see enum rx_handler_result.
3521 */
3522 int netdev_rx_handler_register(struct net_device *dev,
3523 rx_handler_func_t *rx_handler,
3524 void *rx_handler_data)
3525 {
3526 ASSERT_RTNL();
3527
3528 if (dev->rx_handler)
3529 return -EBUSY;
3530
3531 /* Note: rx_handler_data must be set before rx_handler */
3532 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3533 rcu_assign_pointer(dev->rx_handler, rx_handler);
3534
3535 return 0;
3536 }
3537 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3538
3539 /**
3540 * netdev_rx_handler_unregister - unregister receive handler
3541 * @dev: device to unregister a handler from
3542 *
3543 * Unregister a receive handler from a device.
3544 *
3545 * The caller must hold the rtnl_mutex.
3546 */
3547 void netdev_rx_handler_unregister(struct net_device *dev)
3548 {
3549
3550 ASSERT_RTNL();
3551 RCU_INIT_POINTER(dev->rx_handler, NULL);
3552 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3553 * section has a guarantee to see a non NULL rx_handler_data
3554 * as well.
3555 */
3556 synchronize_net();
3557 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3558 }
3559 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3560
3561 /*
3562 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3563 * the special handling of PFMEMALLOC skbs.
3564 */
3565 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3566 {
3567 switch (skb->protocol) {
3568 case htons(ETH_P_ARP):
3569 case htons(ETH_P_IP):
3570 case htons(ETH_P_IPV6):
3571 case htons(ETH_P_8021Q):
3572 case htons(ETH_P_8021AD):
3573 return true;
3574 default:
3575 return false;
3576 }
3577 }
3578
3579 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3580 {
3581 struct packet_type *ptype, *pt_prev;
3582 rx_handler_func_t *rx_handler;
3583 struct net_device *orig_dev;
3584 struct net_device *null_or_dev;
3585 bool deliver_exact = false;
3586 int ret = NET_RX_DROP;
3587 __be16 type;
3588
3589 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3590
3591 trace_netif_receive_skb(skb);
3592
3593 orig_dev = skb->dev;
3594
3595 skb_reset_network_header(skb);
3596 if (!skb_transport_header_was_set(skb))
3597 skb_reset_transport_header(skb);
3598 skb_reset_mac_len(skb);
3599
3600 pt_prev = NULL;
3601
3602 rcu_read_lock();
3603
3604 another_round:
3605 skb->skb_iif = skb->dev->ifindex;
3606
3607 __this_cpu_inc(softnet_data.processed);
3608
3609 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3610 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3611 skb = skb_vlan_untag(skb);
3612 if (unlikely(!skb))
3613 goto unlock;
3614 }
3615
3616 #ifdef CONFIG_NET_CLS_ACT
3617 if (skb->tc_verd & TC_NCLS) {
3618 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3619 goto ncls;
3620 }
3621 #endif
3622
3623 if (pfmemalloc)
3624 goto skip_taps;
3625
3626 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3627 if (!ptype->dev || ptype->dev == skb->dev) {
3628 if (pt_prev)
3629 ret = deliver_skb(skb, pt_prev, orig_dev);
3630 pt_prev = ptype;
3631 }
3632 }
3633
3634 skip_taps:
3635 #ifdef CONFIG_NET_CLS_ACT
3636 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3637 if (!skb)
3638 goto unlock;
3639 ncls:
3640 #endif
3641
3642 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3643 goto drop;
3644
3645 if (vlan_tx_tag_present(skb)) {
3646 if (pt_prev) {
3647 ret = deliver_skb(skb, pt_prev, orig_dev);
3648 pt_prev = NULL;
3649 }
3650 if (vlan_do_receive(&skb))
3651 goto another_round;
3652 else if (unlikely(!skb))
3653 goto unlock;
3654 }
3655
3656 rx_handler = rcu_dereference(skb->dev->rx_handler);
3657 if (rx_handler) {
3658 if (pt_prev) {
3659 ret = deliver_skb(skb, pt_prev, orig_dev);
3660 pt_prev = NULL;
3661 }
3662 switch (rx_handler(&skb)) {
3663 case RX_HANDLER_CONSUMED:
3664 ret = NET_RX_SUCCESS;
3665 goto unlock;
3666 case RX_HANDLER_ANOTHER:
3667 goto another_round;
3668 case RX_HANDLER_EXACT:
3669 deliver_exact = true;
3670 case RX_HANDLER_PASS:
3671 break;
3672 default:
3673 BUG();
3674 }
3675 }
3676
3677 if (unlikely(vlan_tx_tag_present(skb))) {
3678 if (vlan_tx_tag_get_id(skb))
3679 skb->pkt_type = PACKET_OTHERHOST;
3680 /* Note: we might in the future use prio bits
3681 * and set skb->priority like in vlan_do_receive()
3682 * For the time being, just ignore Priority Code Point
3683 */
3684 skb->vlan_tci = 0;
3685 }
3686
3687 /* deliver only exact match when indicated */
3688 null_or_dev = deliver_exact ? skb->dev : NULL;
3689
3690 type = skb->protocol;
3691 list_for_each_entry_rcu(ptype,
3692 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3693 if (ptype->type == type &&
3694 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3695 ptype->dev == orig_dev)) {
3696 if (pt_prev)
3697 ret = deliver_skb(skb, pt_prev, orig_dev);
3698 pt_prev = ptype;
3699 }
3700 }
3701
3702 if (pt_prev) {
3703 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3704 goto drop;
3705 else
3706 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3707 } else {
3708 drop:
3709 atomic_long_inc(&skb->dev->rx_dropped);
3710 kfree_skb(skb);
3711 /* Jamal, now you will not able to escape explaining
3712 * me how you were going to use this. :-)
3713 */
3714 ret = NET_RX_DROP;
3715 }
3716
3717 unlock:
3718 rcu_read_unlock();
3719 return ret;
3720 }
3721
3722 static int __netif_receive_skb(struct sk_buff *skb)
3723 {
3724 int ret;
3725
3726 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3727 unsigned long pflags = current->flags;
3728
3729 /*
3730 * PFMEMALLOC skbs are special, they should
3731 * - be delivered to SOCK_MEMALLOC sockets only
3732 * - stay away from userspace
3733 * - have bounded memory usage
3734 *
3735 * Use PF_MEMALLOC as this saves us from propagating the allocation
3736 * context down to all allocation sites.
3737 */
3738 current->flags |= PF_MEMALLOC;
3739 ret = __netif_receive_skb_core(skb, true);
3740 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3741 } else
3742 ret = __netif_receive_skb_core(skb, false);
3743
3744 return ret;
3745 }
3746
3747 static int netif_receive_skb_internal(struct sk_buff *skb)
3748 {
3749 net_timestamp_check(netdev_tstamp_prequeue, skb);
3750
3751 if (skb_defer_rx_timestamp(skb))
3752 return NET_RX_SUCCESS;
3753
3754 #ifdef CONFIG_RPS
3755 if (static_key_false(&rps_needed)) {
3756 struct rps_dev_flow voidflow, *rflow = &voidflow;
3757 int cpu, ret;
3758
3759 rcu_read_lock();
3760
3761 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3762
3763 if (cpu >= 0) {
3764 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3765 rcu_read_unlock();
3766 return ret;
3767 }
3768 rcu_read_unlock();
3769 }
3770 #endif
3771 return __netif_receive_skb(skb);
3772 }
3773
3774 /**
3775 * netif_receive_skb - process receive buffer from network
3776 * @skb: buffer to process
3777 *
3778 * netif_receive_skb() is the main receive data processing function.
3779 * It always succeeds. The buffer may be dropped during processing
3780 * for congestion control or by the protocol layers.
3781 *
3782 * This function may only be called from softirq context and interrupts
3783 * should be enabled.
3784 *
3785 * Return values (usually ignored):
3786 * NET_RX_SUCCESS: no congestion
3787 * NET_RX_DROP: packet was dropped
3788 */
3789 int netif_receive_skb(struct sk_buff *skb)
3790 {
3791 trace_netif_receive_skb_entry(skb);
3792
3793 return netif_receive_skb_internal(skb);
3794 }
3795 EXPORT_SYMBOL(netif_receive_skb);
3796
3797 /* Network device is going away, flush any packets still pending
3798 * Called with irqs disabled.
3799 */
3800 static void flush_backlog(void *arg)
3801 {
3802 struct net_device *dev = arg;
3803 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3804 struct sk_buff *skb, *tmp;
3805
3806 rps_lock(sd);
3807 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3808 if (skb->dev == dev) {
3809 __skb_unlink(skb, &sd->input_pkt_queue);
3810 kfree_skb(skb);
3811 input_queue_head_incr(sd);
3812 }
3813 }
3814 rps_unlock(sd);
3815
3816 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3817 if (skb->dev == dev) {
3818 __skb_unlink(skb, &sd->process_queue);
3819 kfree_skb(skb);
3820 input_queue_head_incr(sd);
3821 }
3822 }
3823 }
3824
3825 static int napi_gro_complete(struct sk_buff *skb)
3826 {
3827 struct packet_offload *ptype;
3828 __be16 type = skb->protocol;
3829 struct list_head *head = &offload_base;
3830 int err = -ENOENT;
3831
3832 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3833
3834 if (NAPI_GRO_CB(skb)->count == 1) {
3835 skb_shinfo(skb)->gso_size = 0;
3836 goto out;
3837 }
3838
3839 rcu_read_lock();
3840 list_for_each_entry_rcu(ptype, head, list) {
3841 if (ptype->type != type || !ptype->callbacks.gro_complete)
3842 continue;
3843
3844 err = ptype->callbacks.gro_complete(skb, 0);
3845 break;
3846 }
3847 rcu_read_unlock();
3848
3849 if (err) {
3850 WARN_ON(&ptype->list == head);
3851 kfree_skb(skb);
3852 return NET_RX_SUCCESS;
3853 }
3854
3855 out:
3856 return netif_receive_skb_internal(skb);
3857 }
3858
3859 /* napi->gro_list contains packets ordered by age.
3860 * youngest packets at the head of it.
3861 * Complete skbs in reverse order to reduce latencies.
3862 */
3863 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3864 {
3865 struct sk_buff *skb, *prev = NULL;
3866
3867 /* scan list and build reverse chain */
3868 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3869 skb->prev = prev;
3870 prev = skb;
3871 }
3872
3873 for (skb = prev; skb; skb = prev) {
3874 skb->next = NULL;
3875
3876 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3877 return;
3878
3879 prev = skb->prev;
3880 napi_gro_complete(skb);
3881 napi->gro_count--;
3882 }
3883
3884 napi->gro_list = NULL;
3885 }
3886 EXPORT_SYMBOL(napi_gro_flush);
3887
3888 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3889 {
3890 struct sk_buff *p;
3891 unsigned int maclen = skb->dev->hard_header_len;
3892 u32 hash = skb_get_hash_raw(skb);
3893
3894 for (p = napi->gro_list; p; p = p->next) {
3895 unsigned long diffs;
3896
3897 NAPI_GRO_CB(p)->flush = 0;
3898
3899 if (hash != skb_get_hash_raw(p)) {
3900 NAPI_GRO_CB(p)->same_flow = 0;
3901 continue;
3902 }
3903
3904 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3905 diffs |= p->vlan_tci ^ skb->vlan_tci;
3906 if (maclen == ETH_HLEN)
3907 diffs |= compare_ether_header(skb_mac_header(p),
3908 skb_mac_header(skb));
3909 else if (!diffs)
3910 diffs = memcmp(skb_mac_header(p),
3911 skb_mac_header(skb),
3912 maclen);
3913 NAPI_GRO_CB(p)->same_flow = !diffs;
3914 }
3915 }
3916
3917 static void skb_gro_reset_offset(struct sk_buff *skb)
3918 {
3919 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3920 const skb_frag_t *frag0 = &pinfo->frags[0];
3921
3922 NAPI_GRO_CB(skb)->data_offset = 0;
3923 NAPI_GRO_CB(skb)->frag0 = NULL;
3924 NAPI_GRO_CB(skb)->frag0_len = 0;
3925
3926 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3927 pinfo->nr_frags &&
3928 !PageHighMem(skb_frag_page(frag0))) {
3929 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3930 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3931 }
3932 }
3933
3934 static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
3935 {
3936 struct skb_shared_info *pinfo = skb_shinfo(skb);
3937
3938 BUG_ON(skb->end - skb->tail < grow);
3939
3940 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3941
3942 skb->data_len -= grow;
3943 skb->tail += grow;
3944
3945 pinfo->frags[0].page_offset += grow;
3946 skb_frag_size_sub(&pinfo->frags[0], grow);
3947
3948 if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
3949 skb_frag_unref(skb, 0);
3950 memmove(pinfo->frags, pinfo->frags + 1,
3951 --pinfo->nr_frags * sizeof(pinfo->frags[0]));
3952 }
3953 }
3954
3955 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3956 {
3957 struct sk_buff **pp = NULL;
3958 struct packet_offload *ptype;
3959 __be16 type = skb->protocol;
3960 struct list_head *head = &offload_base;
3961 int same_flow;
3962 enum gro_result ret;
3963 int grow;
3964
3965 if (!(skb->dev->features & NETIF_F_GRO))
3966 goto normal;
3967
3968 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3969 goto normal;
3970
3971 gro_list_prepare(napi, skb);
3972 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3973
3974 rcu_read_lock();
3975 list_for_each_entry_rcu(ptype, head, list) {
3976 if (ptype->type != type || !ptype->callbacks.gro_receive)
3977 continue;
3978
3979 skb_set_network_header(skb, skb_gro_offset(skb));
3980 skb_reset_mac_len(skb);
3981 NAPI_GRO_CB(skb)->same_flow = 0;
3982 NAPI_GRO_CB(skb)->flush = 0;
3983 NAPI_GRO_CB(skb)->free = 0;
3984 NAPI_GRO_CB(skb)->udp_mark = 0;
3985
3986 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3987 break;
3988 }
3989 rcu_read_unlock();
3990
3991 if (&ptype->list == head)
3992 goto normal;
3993
3994 same_flow = NAPI_GRO_CB(skb)->same_flow;
3995 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3996
3997 if (pp) {
3998 struct sk_buff *nskb = *pp;
3999
4000 *pp = nskb->next;
4001 nskb->next = NULL;
4002 napi_gro_complete(nskb);
4003 napi->gro_count--;
4004 }
4005
4006 if (same_flow)
4007 goto ok;
4008
4009 if (NAPI_GRO_CB(skb)->flush)
4010 goto normal;
4011
4012 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
4013 struct sk_buff *nskb = napi->gro_list;
4014
4015 /* locate the end of the list to select the 'oldest' flow */
4016 while (nskb->next) {
4017 pp = &nskb->next;
4018 nskb = *pp;
4019 }
4020 *pp = NULL;
4021 nskb->next = NULL;
4022 napi_gro_complete(nskb);
4023 } else {
4024 napi->gro_count++;
4025 }
4026 NAPI_GRO_CB(skb)->count = 1;
4027 NAPI_GRO_CB(skb)->age = jiffies;
4028 NAPI_GRO_CB(skb)->last = skb;
4029 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4030 skb->next = napi->gro_list;
4031 napi->gro_list = skb;
4032 ret = GRO_HELD;
4033
4034 pull:
4035 grow = skb_gro_offset(skb) - skb_headlen(skb);
4036 if (grow > 0)
4037 gro_pull_from_frag0(skb, grow);
4038 ok:
4039 return ret;
4040
4041 normal:
4042 ret = GRO_NORMAL;
4043 goto pull;
4044 }
4045
4046 struct packet_offload *gro_find_receive_by_type(__be16 type)
4047 {
4048 struct list_head *offload_head = &offload_base;
4049 struct packet_offload *ptype;
4050
4051 list_for_each_entry_rcu(ptype, offload_head, list) {
4052 if (ptype->type != type || !ptype->callbacks.gro_receive)
4053 continue;
4054 return ptype;
4055 }
4056 return NULL;
4057 }
4058 EXPORT_SYMBOL(gro_find_receive_by_type);
4059
4060 struct packet_offload *gro_find_complete_by_type(__be16 type)
4061 {
4062 struct list_head *offload_head = &offload_base;
4063 struct packet_offload *ptype;
4064
4065 list_for_each_entry_rcu(ptype, offload_head, list) {
4066 if (ptype->type != type || !ptype->callbacks.gro_complete)
4067 continue;
4068 return ptype;
4069 }
4070 return NULL;
4071 }
4072 EXPORT_SYMBOL(gro_find_complete_by_type);
4073
4074 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4075 {
4076 switch (ret) {
4077 case GRO_NORMAL:
4078 if (netif_receive_skb_internal(skb))
4079 ret = GRO_DROP;
4080 break;
4081
4082 case GRO_DROP:
4083 kfree_skb(skb);
4084 break;
4085
4086 case GRO_MERGED_FREE:
4087 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
4088 kmem_cache_free(skbuff_head_cache, skb);
4089 else
4090 __kfree_skb(skb);
4091 break;
4092
4093 case GRO_HELD:
4094 case GRO_MERGED:
4095 break;
4096 }
4097
4098 return ret;
4099 }
4100
4101 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4102 {
4103 trace_napi_gro_receive_entry(skb);
4104
4105 skb_gro_reset_offset(skb);
4106
4107 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4108 }
4109 EXPORT_SYMBOL(napi_gro_receive);
4110
4111 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4112 {
4113 __skb_pull(skb, skb_headlen(skb));
4114 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4115 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4116 skb->vlan_tci = 0;
4117 skb->dev = napi->dev;
4118 skb->skb_iif = 0;
4119 skb->encapsulation = 0;
4120 skb_shinfo(skb)->gso_type = 0;
4121 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4122
4123 napi->skb = skb;
4124 }
4125
4126 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4127 {
4128 struct sk_buff *skb = napi->skb;
4129
4130 if (!skb) {
4131 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4132 napi->skb = skb;
4133 }
4134 return skb;
4135 }
4136 EXPORT_SYMBOL(napi_get_frags);
4137
4138 static gro_result_t napi_frags_finish(struct napi_struct *napi,
4139 struct sk_buff *skb,
4140 gro_result_t ret)
4141 {
4142 switch (ret) {
4143 case GRO_NORMAL:
4144 case GRO_HELD:
4145 __skb_push(skb, ETH_HLEN);
4146 skb->protocol = eth_type_trans(skb, skb->dev);
4147 if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4148 ret = GRO_DROP;
4149 break;
4150
4151 case GRO_DROP:
4152 case GRO_MERGED_FREE:
4153 napi_reuse_skb(napi, skb);
4154 break;
4155
4156 case GRO_MERGED:
4157 break;
4158 }
4159
4160 return ret;
4161 }
4162
4163 /* Upper GRO stack assumes network header starts at gro_offset=0
4164 * Drivers could call both napi_gro_frags() and napi_gro_receive()
4165 * We copy ethernet header into skb->data to have a common layout.
4166 */
4167 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4168 {
4169 struct sk_buff *skb = napi->skb;
4170 const struct ethhdr *eth;
4171 unsigned int hlen = sizeof(*eth);
4172
4173 napi->skb = NULL;
4174
4175 skb_reset_mac_header(skb);
4176 skb_gro_reset_offset(skb);
4177
4178 eth = skb_gro_header_fast(skb, 0);
4179 if (unlikely(skb_gro_header_hard(skb, hlen))) {
4180 eth = skb_gro_header_slow(skb, hlen, 0);
4181 if (unlikely(!eth)) {
4182 napi_reuse_skb(napi, skb);
4183 return NULL;
4184 }
4185 } else {
4186 gro_pull_from_frag0(skb, hlen);
4187 NAPI_GRO_CB(skb)->frag0 += hlen;
4188 NAPI_GRO_CB(skb)->frag0_len -= hlen;
4189 }
4190 __skb_pull(skb, hlen);
4191
4192 /*
4193 * This works because the only protocols we care about don't require
4194 * special handling.
4195 * We'll fix it up properly in napi_frags_finish()
4196 */
4197 skb->protocol = eth->h_proto;
4198
4199 return skb;
4200 }
4201
4202 gro_result_t napi_gro_frags(struct napi_struct *napi)
4203 {
4204 struct sk_buff *skb = napi_frags_skb(napi);
4205
4206 if (!skb)
4207 return GRO_DROP;
4208
4209 trace_napi_gro_frags_entry(skb);
4210
4211 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4212 }
4213 EXPORT_SYMBOL(napi_gro_frags);
4214
4215 /*
4216 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4217 * Note: called with local irq disabled, but exits with local irq enabled.
4218 */
4219 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4220 {
4221 #ifdef CONFIG_RPS
4222 struct softnet_data *remsd = sd->rps_ipi_list;
4223
4224 if (remsd) {
4225 sd->rps_ipi_list = NULL;
4226
4227 local_irq_enable();
4228
4229 /* Send pending IPI's to kick RPS processing on remote cpus. */
4230 while (remsd) {
4231 struct softnet_data *next = remsd->rps_ipi_next;
4232
4233 if (cpu_online(remsd->cpu))
4234 smp_call_function_single_async(remsd->cpu,
4235 &remsd->csd);
4236 remsd = next;
4237 }
4238 } else
4239 #endif
4240 local_irq_enable();
4241 }
4242
4243 static int process_backlog(struct napi_struct *napi, int quota)
4244 {
4245 int work = 0;
4246 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4247
4248 #ifdef CONFIG_RPS
4249 /* Check if we have pending ipi, its better to send them now,
4250 * not waiting net_rx_action() end.
4251 */
4252 if (sd->rps_ipi_list) {
4253 local_irq_disable();
4254 net_rps_action_and_irq_enable(sd);
4255 }
4256 #endif
4257 napi->weight = weight_p;
4258 local_irq_disable();
4259 while (1) {
4260 struct sk_buff *skb;
4261
4262 while ((skb = __skb_dequeue(&sd->process_queue))) {
4263 local_irq_enable();
4264 __netif_receive_skb(skb);
4265 local_irq_disable();
4266 input_queue_head_incr(sd);
4267 if (++work >= quota) {
4268 local_irq_enable();
4269 return work;
4270 }
4271 }
4272
4273 rps_lock(sd);
4274 if (skb_queue_empty(&sd->input_pkt_queue)) {
4275 /*
4276 * Inline a custom version of __napi_complete().
4277 * only current cpu owns and manipulates this napi,
4278 * and NAPI_STATE_SCHED is the only possible flag set
4279 * on backlog.
4280 * We can use a plain write instead of clear_bit(),
4281 * and we dont need an smp_mb() memory barrier.
4282 */
4283 list_del(&napi->poll_list);
4284 napi->state = 0;
4285 rps_unlock(sd);
4286
4287 break;
4288 }
4289
4290 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4291 &sd->process_queue);
4292 rps_unlock(sd);
4293 }
4294 local_irq_enable();
4295
4296 return work;
4297 }
4298
4299 /**
4300 * __napi_schedule - schedule for receive
4301 * @n: entry to schedule
4302 *
4303 * The entry's receive function will be scheduled to run
4304 */
4305 void __napi_schedule(struct napi_struct *n)
4306 {
4307 unsigned long flags;
4308
4309 local_irq_save(flags);
4310 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4311 local_irq_restore(flags);
4312 }
4313 EXPORT_SYMBOL(__napi_schedule);
4314
4315 void __napi_complete(struct napi_struct *n)
4316 {
4317 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4318 BUG_ON(n->gro_list);
4319
4320 list_del(&n->poll_list);
4321 smp_mb__before_atomic();
4322 clear_bit(NAPI_STATE_SCHED, &n->state);
4323 }
4324 EXPORT_SYMBOL(__napi_complete);
4325
4326 void napi_complete(struct napi_struct *n)
4327 {
4328 unsigned long flags;
4329
4330 /*
4331 * don't let napi dequeue from the cpu poll list
4332 * just in case its running on a different cpu
4333 */
4334 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4335 return;
4336
4337 napi_gro_flush(n, false);
4338 local_irq_save(flags);
4339 __napi_complete(n);
4340 local_irq_restore(flags);
4341 }
4342 EXPORT_SYMBOL(napi_complete);
4343
4344 /* must be called under rcu_read_lock(), as we dont take a reference */
4345 struct napi_struct *napi_by_id(unsigned int napi_id)
4346 {
4347 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4348 struct napi_struct *napi;
4349
4350 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4351 if (napi->napi_id == napi_id)
4352 return napi;
4353
4354 return NULL;
4355 }
4356 EXPORT_SYMBOL_GPL(napi_by_id);
4357
4358 void napi_hash_add(struct napi_struct *napi)
4359 {
4360 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4361
4362 spin_lock(&napi_hash_lock);
4363
4364 /* 0 is not a valid id, we also skip an id that is taken
4365 * we expect both events to be extremely rare
4366 */
4367 napi->napi_id = 0;
4368 while (!napi->napi_id) {
4369 napi->napi_id = ++napi_gen_id;
4370 if (napi_by_id(napi->napi_id))
4371 napi->napi_id = 0;
4372 }
4373
4374 hlist_add_head_rcu(&napi->napi_hash_node,
4375 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4376
4377 spin_unlock(&napi_hash_lock);
4378 }
4379 }
4380 EXPORT_SYMBOL_GPL(napi_hash_add);
4381
4382 /* Warning : caller is responsible to make sure rcu grace period
4383 * is respected before freeing memory containing @napi
4384 */
4385 void napi_hash_del(struct napi_struct *napi)
4386 {
4387 spin_lock(&napi_hash_lock);
4388
4389 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4390 hlist_del_rcu(&napi->napi_hash_node);
4391
4392 spin_unlock(&napi_hash_lock);
4393 }
4394 EXPORT_SYMBOL_GPL(napi_hash_del);
4395
4396 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4397 int (*poll)(struct napi_struct *, int), int weight)
4398 {
4399 INIT_LIST_HEAD(&napi->poll_list);
4400 napi->gro_count = 0;
4401 napi->gro_list = NULL;
4402 napi->skb = NULL;
4403 napi->poll = poll;
4404 if (weight > NAPI_POLL_WEIGHT)
4405 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4406 weight, dev->name);
4407 napi->weight = weight;
4408 list_add(&napi->dev_list, &dev->napi_list);
4409 napi->dev = dev;
4410 #ifdef CONFIG_NETPOLL
4411 spin_lock_init(&napi->poll_lock);
4412 napi->poll_owner = -1;
4413 #endif
4414 set_bit(NAPI_STATE_SCHED, &napi->state);
4415 }
4416 EXPORT_SYMBOL(netif_napi_add);
4417
4418 void netif_napi_del(struct napi_struct *napi)
4419 {
4420 list_del_init(&napi->dev_list);
4421 napi_free_frags(napi);
4422
4423 kfree_skb_list(napi->gro_list);
4424 napi->gro_list = NULL;
4425 napi->gro_count = 0;
4426 }
4427 EXPORT_SYMBOL(netif_napi_del);
4428
4429 static void net_rx_action(struct softirq_action *h)
4430 {
4431 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4432 unsigned long time_limit = jiffies + 2;
4433 int budget = netdev_budget;
4434 void *have;
4435
4436 local_irq_disable();
4437
4438 while (!list_empty(&sd->poll_list)) {
4439 struct napi_struct *n;
4440 int work, weight;
4441
4442 /* If softirq window is exhuasted then punt.
4443 * Allow this to run for 2 jiffies since which will allow
4444 * an average latency of 1.5/HZ.
4445 */
4446 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4447 goto softnet_break;
4448
4449 local_irq_enable();
4450
4451 /* Even though interrupts have been re-enabled, this
4452 * access is safe because interrupts can only add new
4453 * entries to the tail of this list, and only ->poll()
4454 * calls can remove this head entry from the list.
4455 */
4456 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4457
4458 have = netpoll_poll_lock(n);
4459
4460 weight = n->weight;
4461
4462 /* This NAPI_STATE_SCHED test is for avoiding a race
4463 * with netpoll's poll_napi(). Only the entity which
4464 * obtains the lock and sees NAPI_STATE_SCHED set will
4465 * actually make the ->poll() call. Therefore we avoid
4466 * accidentally calling ->poll() when NAPI is not scheduled.
4467 */
4468 work = 0;
4469 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4470 work = n->poll(n, weight);
4471 trace_napi_poll(n);
4472 }
4473
4474 WARN_ON_ONCE(work > weight);
4475
4476 budget -= work;
4477
4478 local_irq_disable();
4479
4480 /* Drivers must not modify the NAPI state if they
4481 * consume the entire weight. In such cases this code
4482 * still "owns" the NAPI instance and therefore can
4483 * move the instance around on the list at-will.
4484 */
4485 if (unlikely(work == weight)) {
4486 if (unlikely(napi_disable_pending(n))) {
4487 local_irq_enable();
4488 napi_complete(n);
4489 local_irq_disable();
4490 } else {
4491 if (n->gro_list) {
4492 /* flush too old packets
4493 * If HZ < 1000, flush all packets.
4494 */
4495 local_irq_enable();
4496 napi_gro_flush(n, HZ >= 1000);
4497 local_irq_disable();
4498 }
4499 list_move_tail(&n->poll_list, &sd->poll_list);
4500 }
4501 }
4502
4503 netpoll_poll_unlock(have);
4504 }
4505 out:
4506 net_rps_action_and_irq_enable(sd);
4507
4508 #ifdef CONFIG_NET_DMA
4509 /*
4510 * There may not be any more sk_buffs coming right now, so push
4511 * any pending DMA copies to hardware
4512 */
4513 dma_issue_pending_all();
4514 #endif
4515
4516 return;
4517
4518 softnet_break:
4519 sd->time_squeeze++;
4520 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4521 goto out;
4522 }
4523
4524 struct netdev_adjacent {
4525 struct net_device *dev;
4526
4527 /* upper master flag, there can only be one master device per list */
4528 bool master;
4529
4530 /* counter for the number of times this device was added to us */
4531 u16 ref_nr;
4532
4533 /* private field for the users */
4534 void *private;
4535
4536 struct list_head list;
4537 struct rcu_head rcu;
4538 };
4539
4540 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4541 struct net_device *adj_dev,
4542 struct list_head *adj_list)
4543 {
4544 struct netdev_adjacent *adj;
4545
4546 list_for_each_entry(adj, adj_list, list) {
4547 if (adj->dev == adj_dev)
4548 return adj;
4549 }
4550 return NULL;
4551 }
4552
4553 /**
4554 * netdev_has_upper_dev - Check if device is linked to an upper device
4555 * @dev: device
4556 * @upper_dev: upper device to check
4557 *
4558 * Find out if a device is linked to specified upper device and return true
4559 * in case it is. Note that this checks only immediate upper device,
4560 * not through a complete stack of devices. The caller must hold the RTNL lock.
4561 */
4562 bool netdev_has_upper_dev(struct net_device *dev,
4563 struct net_device *upper_dev)
4564 {
4565 ASSERT_RTNL();
4566
4567 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4568 }
4569 EXPORT_SYMBOL(netdev_has_upper_dev);
4570
4571 /**
4572 * netdev_has_any_upper_dev - Check if device is linked to some device
4573 * @dev: device
4574 *
4575 * Find out if a device is linked to an upper device and return true in case
4576 * it is. The caller must hold the RTNL lock.
4577 */
4578 static bool netdev_has_any_upper_dev(struct net_device *dev)
4579 {
4580 ASSERT_RTNL();
4581
4582 return !list_empty(&dev->all_adj_list.upper);
4583 }
4584
4585 /**
4586 * netdev_master_upper_dev_get - 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 RTNL lock.
4591 */
4592 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4593 {
4594 struct netdev_adjacent *upper;
4595
4596 ASSERT_RTNL();
4597
4598 if (list_empty(&dev->adj_list.upper))
4599 return NULL;
4600
4601 upper = list_first_entry(&dev->adj_list.upper,
4602 struct netdev_adjacent, list);
4603 if (likely(upper->master))
4604 return upper->dev;
4605 return NULL;
4606 }
4607 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4608
4609 void *netdev_adjacent_get_private(struct list_head *adj_list)
4610 {
4611 struct netdev_adjacent *adj;
4612
4613 adj = list_entry(adj_list, struct netdev_adjacent, list);
4614
4615 return adj->private;
4616 }
4617 EXPORT_SYMBOL(netdev_adjacent_get_private);
4618
4619 /**
4620 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
4621 * @dev: device
4622 * @iter: list_head ** of the current position
4623 *
4624 * Gets the next device from the dev's upper list, starting from iter
4625 * position. The caller must hold RCU read lock.
4626 */
4627 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
4628 struct list_head **iter)
4629 {
4630 struct netdev_adjacent *upper;
4631
4632 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4633
4634 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4635
4636 if (&upper->list == &dev->adj_list.upper)
4637 return NULL;
4638
4639 *iter = &upper->list;
4640
4641 return upper->dev;
4642 }
4643 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
4644
4645 /**
4646 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4647 * @dev: device
4648 * @iter: list_head ** of the current position
4649 *
4650 * Gets the next device from the dev's upper list, starting from iter
4651 * position. The caller must hold RCU read lock.
4652 */
4653 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4654 struct list_head **iter)
4655 {
4656 struct netdev_adjacent *upper;
4657
4658 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4659
4660 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4661
4662 if (&upper->list == &dev->all_adj_list.upper)
4663 return NULL;
4664
4665 *iter = &upper->list;
4666
4667 return upper->dev;
4668 }
4669 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4670
4671 /**
4672 * netdev_lower_get_next_private - Get the next ->private from the
4673 * lower neighbour list
4674 * @dev: device
4675 * @iter: list_head ** of the current position
4676 *
4677 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4678 * list, starting from iter position. The caller must hold either hold the
4679 * RTNL lock or its own locking that guarantees that the neighbour lower
4680 * list will remain unchainged.
4681 */
4682 void *netdev_lower_get_next_private(struct net_device *dev,
4683 struct list_head **iter)
4684 {
4685 struct netdev_adjacent *lower;
4686
4687 lower = list_entry(*iter, struct netdev_adjacent, list);
4688
4689 if (&lower->list == &dev->adj_list.lower)
4690 return NULL;
4691
4692 *iter = lower->list.next;
4693
4694 return lower->private;
4695 }
4696 EXPORT_SYMBOL(netdev_lower_get_next_private);
4697
4698 /**
4699 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4700 * lower neighbour list, RCU
4701 * variant
4702 * @dev: device
4703 * @iter: list_head ** of the current position
4704 *
4705 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4706 * list, starting from iter position. The caller must hold RCU read lock.
4707 */
4708 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4709 struct list_head **iter)
4710 {
4711 struct netdev_adjacent *lower;
4712
4713 WARN_ON_ONCE(!rcu_read_lock_held());
4714
4715 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4716
4717 if (&lower->list == &dev->adj_list.lower)
4718 return NULL;
4719
4720 *iter = &lower->list;
4721
4722 return lower->private;
4723 }
4724 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4725
4726 /**
4727 * netdev_lower_get_next - Get the next device from the lower neighbour
4728 * list
4729 * @dev: device
4730 * @iter: list_head ** of the current position
4731 *
4732 * Gets the next netdev_adjacent from the dev's lower neighbour
4733 * list, starting from iter position. The caller must hold RTNL lock or
4734 * its own locking that guarantees that the neighbour lower
4735 * list will remain unchainged.
4736 */
4737 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
4738 {
4739 struct netdev_adjacent *lower;
4740
4741 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
4742
4743 if (&lower->list == &dev->adj_list.lower)
4744 return NULL;
4745
4746 *iter = &lower->list;
4747
4748 return lower->dev;
4749 }
4750 EXPORT_SYMBOL(netdev_lower_get_next);
4751
4752 /**
4753 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4754 * lower neighbour list, RCU
4755 * variant
4756 * @dev: device
4757 *
4758 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4759 * list. The caller must hold RCU read lock.
4760 */
4761 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4762 {
4763 struct netdev_adjacent *lower;
4764
4765 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4766 struct netdev_adjacent, list);
4767 if (lower)
4768 return lower->private;
4769 return NULL;
4770 }
4771 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4772
4773 /**
4774 * netdev_master_upper_dev_get_rcu - Get master upper device
4775 * @dev: device
4776 *
4777 * Find a master upper device and return pointer to it or NULL in case
4778 * it's not there. The caller must hold the RCU read lock.
4779 */
4780 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4781 {
4782 struct netdev_adjacent *upper;
4783
4784 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4785 struct netdev_adjacent, list);
4786 if (upper && likely(upper->master))
4787 return upper->dev;
4788 return NULL;
4789 }
4790 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4791
4792 static int netdev_adjacent_sysfs_add(struct net_device *dev,
4793 struct net_device *adj_dev,
4794 struct list_head *dev_list)
4795 {
4796 char linkname[IFNAMSIZ+7];
4797 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4798 "upper_%s" : "lower_%s", adj_dev->name);
4799 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
4800 linkname);
4801 }
4802 static void netdev_adjacent_sysfs_del(struct net_device *dev,
4803 char *name,
4804 struct list_head *dev_list)
4805 {
4806 char linkname[IFNAMSIZ+7];
4807 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4808 "upper_%s" : "lower_%s", name);
4809 sysfs_remove_link(&(dev->dev.kobj), linkname);
4810 }
4811
4812 #define netdev_adjacent_is_neigh_list(dev, dev_list) \
4813 (dev_list == &dev->adj_list.upper || \
4814 dev_list == &dev->adj_list.lower)
4815
4816 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4817 struct net_device *adj_dev,
4818 struct list_head *dev_list,
4819 void *private, bool master)
4820 {
4821 struct netdev_adjacent *adj;
4822 int ret;
4823
4824 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4825
4826 if (adj) {
4827 adj->ref_nr++;
4828 return 0;
4829 }
4830
4831 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4832 if (!adj)
4833 return -ENOMEM;
4834
4835 adj->dev = adj_dev;
4836 adj->master = master;
4837 adj->ref_nr = 1;
4838 adj->private = private;
4839 dev_hold(adj_dev);
4840
4841 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4842 adj_dev->name, dev->name, adj_dev->name);
4843
4844 if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
4845 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
4846 if (ret)
4847 goto free_adj;
4848 }
4849
4850 /* Ensure that master link is always the first item in list. */
4851 if (master) {
4852 ret = sysfs_create_link(&(dev->dev.kobj),
4853 &(adj_dev->dev.kobj), "master");
4854 if (ret)
4855 goto remove_symlinks;
4856
4857 list_add_rcu(&adj->list, dev_list);
4858 } else {
4859 list_add_tail_rcu(&adj->list, dev_list);
4860 }
4861
4862 return 0;
4863
4864 remove_symlinks:
4865 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4866 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4867 free_adj:
4868 kfree(adj);
4869 dev_put(adj_dev);
4870
4871 return ret;
4872 }
4873
4874 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4875 struct net_device *adj_dev,
4876 struct list_head *dev_list)
4877 {
4878 struct netdev_adjacent *adj;
4879
4880 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4881
4882 if (!adj) {
4883 pr_err("tried to remove device %s from %s\n",
4884 dev->name, adj_dev->name);
4885 BUG();
4886 }
4887
4888 if (adj->ref_nr > 1) {
4889 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4890 adj->ref_nr-1);
4891 adj->ref_nr--;
4892 return;
4893 }
4894
4895 if (adj->master)
4896 sysfs_remove_link(&(dev->dev.kobj), "master");
4897
4898 if (netdev_adjacent_is_neigh_list(dev, dev_list) &&
4899 net_eq(dev_net(dev),dev_net(adj_dev)))
4900 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4901
4902 list_del_rcu(&adj->list);
4903 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4904 adj_dev->name, dev->name, adj_dev->name);
4905 dev_put(adj_dev);
4906 kfree_rcu(adj, rcu);
4907 }
4908
4909 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4910 struct net_device *upper_dev,
4911 struct list_head *up_list,
4912 struct list_head *down_list,
4913 void *private, bool master)
4914 {
4915 int ret;
4916
4917 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4918 master);
4919 if (ret)
4920 return ret;
4921
4922 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4923 false);
4924 if (ret) {
4925 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4926 return ret;
4927 }
4928
4929 return 0;
4930 }
4931
4932 static int __netdev_adjacent_dev_link(struct net_device *dev,
4933 struct net_device *upper_dev)
4934 {
4935 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4936 &dev->all_adj_list.upper,
4937 &upper_dev->all_adj_list.lower,
4938 NULL, false);
4939 }
4940
4941 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4942 struct net_device *upper_dev,
4943 struct list_head *up_list,
4944 struct list_head *down_list)
4945 {
4946 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4947 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4948 }
4949
4950 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4951 struct net_device *upper_dev)
4952 {
4953 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4954 &dev->all_adj_list.upper,
4955 &upper_dev->all_adj_list.lower);
4956 }
4957
4958 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4959 struct net_device *upper_dev,
4960 void *private, bool master)
4961 {
4962 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4963
4964 if (ret)
4965 return ret;
4966
4967 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4968 &dev->adj_list.upper,
4969 &upper_dev->adj_list.lower,
4970 private, master);
4971 if (ret) {
4972 __netdev_adjacent_dev_unlink(dev, upper_dev);
4973 return ret;
4974 }
4975
4976 return 0;
4977 }
4978
4979 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4980 struct net_device *upper_dev)
4981 {
4982 __netdev_adjacent_dev_unlink(dev, upper_dev);
4983 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4984 &dev->adj_list.upper,
4985 &upper_dev->adj_list.lower);
4986 }
4987
4988 static int __netdev_upper_dev_link(struct net_device *dev,
4989 struct net_device *upper_dev, bool master,
4990 void *private)
4991 {
4992 struct netdev_adjacent *i, *j, *to_i, *to_j;
4993 int ret = 0;
4994
4995 ASSERT_RTNL();
4996
4997 if (dev == upper_dev)
4998 return -EBUSY;
4999
5000 /* To prevent loops, check if dev is not upper device to upper_dev. */
5001 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
5002 return -EBUSY;
5003
5004 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
5005 return -EEXIST;
5006
5007 if (master && netdev_master_upper_dev_get(dev))
5008 return -EBUSY;
5009
5010 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
5011 master);
5012 if (ret)
5013 return ret;
5014
5015 /* Now that we linked these devs, make all the upper_dev's
5016 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5017 * versa, and don't forget the devices itself. All of these
5018 * links are non-neighbours.
5019 */
5020 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5021 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5022 pr_debug("Interlinking %s with %s, non-neighbour\n",
5023 i->dev->name, j->dev->name);
5024 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
5025 if (ret)
5026 goto rollback_mesh;
5027 }
5028 }
5029
5030 /* add dev to every upper_dev's upper device */
5031 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5032 pr_debug("linking %s's upper device %s with %s\n",
5033 upper_dev->name, i->dev->name, dev->name);
5034 ret = __netdev_adjacent_dev_link(dev, i->dev);
5035 if (ret)
5036 goto rollback_upper_mesh;
5037 }
5038
5039 /* add upper_dev to every dev's lower device */
5040 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5041 pr_debug("linking %s's lower device %s with %s\n", dev->name,
5042 i->dev->name, upper_dev->name);
5043 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
5044 if (ret)
5045 goto rollback_lower_mesh;
5046 }
5047
5048 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5049 return 0;
5050
5051 rollback_lower_mesh:
5052 to_i = i;
5053 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5054 if (i == to_i)
5055 break;
5056 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
5057 }
5058
5059 i = NULL;
5060
5061 rollback_upper_mesh:
5062 to_i = i;
5063 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5064 if (i == to_i)
5065 break;
5066 __netdev_adjacent_dev_unlink(dev, i->dev);
5067 }
5068
5069 i = j = NULL;
5070
5071 rollback_mesh:
5072 to_i = i;
5073 to_j = j;
5074 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5075 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5076 if (i == to_i && j == to_j)
5077 break;
5078 __netdev_adjacent_dev_unlink(i->dev, j->dev);
5079 }
5080 if (i == to_i)
5081 break;
5082 }
5083
5084 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5085
5086 return ret;
5087 }
5088
5089 /**
5090 * netdev_upper_dev_link - Add a link to the upper device
5091 * @dev: device
5092 * @upper_dev: new upper device
5093 *
5094 * Adds a link to device which is upper to this one. The caller must hold
5095 * the RTNL lock. On a failure a negative errno code is returned.
5096 * On success the reference counts are adjusted and the function
5097 * returns zero.
5098 */
5099 int netdev_upper_dev_link(struct net_device *dev,
5100 struct net_device *upper_dev)
5101 {
5102 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
5103 }
5104 EXPORT_SYMBOL(netdev_upper_dev_link);
5105
5106 /**
5107 * netdev_master_upper_dev_link - Add a master link to the upper device
5108 * @dev: device
5109 * @upper_dev: new upper device
5110 *
5111 * Adds a link to device which is upper to this one. In this case, only
5112 * one master upper device can be linked, although other non-master devices
5113 * might be linked as well. The caller must hold the RTNL lock.
5114 * On a failure a negative errno code is returned. On success the reference
5115 * counts are adjusted and the function returns zero.
5116 */
5117 int netdev_master_upper_dev_link(struct net_device *dev,
5118 struct net_device *upper_dev)
5119 {
5120 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
5121 }
5122 EXPORT_SYMBOL(netdev_master_upper_dev_link);
5123
5124 int netdev_master_upper_dev_link_private(struct net_device *dev,
5125 struct net_device *upper_dev,
5126 void *private)
5127 {
5128 return __netdev_upper_dev_link(dev, upper_dev, true, private);
5129 }
5130 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
5131
5132 /**
5133 * netdev_upper_dev_unlink - Removes a link to upper device
5134 * @dev: device
5135 * @upper_dev: new upper device
5136 *
5137 * Removes a link to device which is upper to this one. The caller must hold
5138 * the RTNL lock.
5139 */
5140 void netdev_upper_dev_unlink(struct net_device *dev,
5141 struct net_device *upper_dev)
5142 {
5143 struct netdev_adjacent *i, *j;
5144 ASSERT_RTNL();
5145
5146 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5147
5148 /* Here is the tricky part. We must remove all dev's lower
5149 * devices from all upper_dev's upper devices and vice
5150 * versa, to maintain the graph relationship.
5151 */
5152 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5153 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5154 __netdev_adjacent_dev_unlink(i->dev, j->dev);
5155
5156 /* remove also the devices itself from lower/upper device
5157 * list
5158 */
5159 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5160 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
5161
5162 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5163 __netdev_adjacent_dev_unlink(dev, i->dev);
5164
5165 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5166 }
5167 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5168
5169 void netdev_adjacent_add_links(struct net_device *dev)
5170 {
5171 struct netdev_adjacent *iter;
5172
5173 struct net *net = dev_net(dev);
5174
5175 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5176 if (!net_eq(net,dev_net(iter->dev)))
5177 continue;
5178 netdev_adjacent_sysfs_add(iter->dev, dev,
5179 &iter->dev->adj_list.lower);
5180 netdev_adjacent_sysfs_add(dev, iter->dev,
5181 &dev->adj_list.upper);
5182 }
5183
5184 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5185 if (!net_eq(net,dev_net(iter->dev)))
5186 continue;
5187 netdev_adjacent_sysfs_add(iter->dev, dev,
5188 &iter->dev->adj_list.upper);
5189 netdev_adjacent_sysfs_add(dev, iter->dev,
5190 &dev->adj_list.lower);
5191 }
5192 }
5193
5194 void netdev_adjacent_del_links(struct net_device *dev)
5195 {
5196 struct netdev_adjacent *iter;
5197
5198 struct net *net = dev_net(dev);
5199
5200 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5201 if (!net_eq(net,dev_net(iter->dev)))
5202 continue;
5203 netdev_adjacent_sysfs_del(iter->dev, dev->name,
5204 &iter->dev->adj_list.lower);
5205 netdev_adjacent_sysfs_del(dev, iter->dev->name,
5206 &dev->adj_list.upper);
5207 }
5208
5209 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5210 if (!net_eq(net,dev_net(iter->dev)))
5211 continue;
5212 netdev_adjacent_sysfs_del(iter->dev, dev->name,
5213 &iter->dev->adj_list.upper);
5214 netdev_adjacent_sysfs_del(dev, iter->dev->name,
5215 &dev->adj_list.lower);
5216 }
5217 }
5218
5219 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5220 {
5221 struct netdev_adjacent *iter;
5222
5223 struct net *net = dev_net(dev);
5224
5225 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5226 if (!net_eq(net,dev_net(iter->dev)))
5227 continue;
5228 netdev_adjacent_sysfs_del(iter->dev, oldname,
5229 &iter->dev->adj_list.lower);
5230 netdev_adjacent_sysfs_add(iter->dev, dev,
5231 &iter->dev->adj_list.lower);
5232 }
5233
5234 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5235 if (!net_eq(net,dev_net(iter->dev)))
5236 continue;
5237 netdev_adjacent_sysfs_del(iter->dev, oldname,
5238 &iter->dev->adj_list.upper);
5239 netdev_adjacent_sysfs_add(iter->dev, dev,
5240 &iter->dev->adj_list.upper);
5241 }
5242 }
5243
5244 void *netdev_lower_dev_get_private(struct net_device *dev,
5245 struct net_device *lower_dev)
5246 {
5247 struct netdev_adjacent *lower;
5248
5249 if (!lower_dev)
5250 return NULL;
5251 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
5252 if (!lower)
5253 return NULL;
5254
5255 return lower->private;
5256 }
5257 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5258
5259
5260 int dev_get_nest_level(struct net_device *dev,
5261 bool (*type_check)(struct net_device *dev))
5262 {
5263 struct net_device *lower = NULL;
5264 struct list_head *iter;
5265 int max_nest = -1;
5266 int nest;
5267
5268 ASSERT_RTNL();
5269
5270 netdev_for_each_lower_dev(dev, lower, iter) {
5271 nest = dev_get_nest_level(lower, type_check);
5272 if (max_nest < nest)
5273 max_nest = nest;
5274 }
5275
5276 if (type_check(dev))
5277 max_nest++;
5278
5279 return max_nest;
5280 }
5281 EXPORT_SYMBOL(dev_get_nest_level);
5282
5283 static void dev_change_rx_flags(struct net_device *dev, int flags)
5284 {
5285 const struct net_device_ops *ops = dev->netdev_ops;
5286
5287 if (ops->ndo_change_rx_flags)
5288 ops->ndo_change_rx_flags(dev, flags);
5289 }
5290
5291 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5292 {
5293 unsigned int old_flags = dev->flags;
5294 kuid_t uid;
5295 kgid_t gid;
5296
5297 ASSERT_RTNL();
5298
5299 dev->flags |= IFF_PROMISC;
5300 dev->promiscuity += inc;
5301 if (dev->promiscuity == 0) {
5302 /*
5303 * Avoid overflow.
5304 * If inc causes overflow, untouch promisc and return error.
5305 */
5306 if (inc < 0)
5307 dev->flags &= ~IFF_PROMISC;
5308 else {
5309 dev->promiscuity -= inc;
5310 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5311 dev->name);
5312 return -EOVERFLOW;
5313 }
5314 }
5315 if (dev->flags != old_flags) {
5316 pr_info("device %s %s promiscuous mode\n",
5317 dev->name,
5318 dev->flags & IFF_PROMISC ? "entered" : "left");
5319 if (audit_enabled) {
5320 current_uid_gid(&uid, &gid);
5321 audit_log(current->audit_context, GFP_ATOMIC,
5322 AUDIT_ANOM_PROMISCUOUS,
5323 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5324 dev->name, (dev->flags & IFF_PROMISC),
5325 (old_flags & IFF_PROMISC),
5326 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5327 from_kuid(&init_user_ns, uid),
5328 from_kgid(&init_user_ns, gid),
5329 audit_get_sessionid(current));
5330 }
5331
5332 dev_change_rx_flags(dev, IFF_PROMISC);
5333 }
5334 if (notify)
5335 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5336 return 0;
5337 }
5338
5339 /**
5340 * dev_set_promiscuity - update promiscuity count on a device
5341 * @dev: device
5342 * @inc: modifier
5343 *
5344 * Add or remove promiscuity from a device. While the count in the device
5345 * remains above zero the interface remains promiscuous. Once it hits zero
5346 * the device reverts back to normal filtering operation. A negative inc
5347 * value is used to drop promiscuity on the device.
5348 * Return 0 if successful or a negative errno code on error.
5349 */
5350 int dev_set_promiscuity(struct net_device *dev, int inc)
5351 {
5352 unsigned int old_flags = dev->flags;
5353 int err;
5354
5355 err = __dev_set_promiscuity(dev, inc, true);
5356 if (err < 0)
5357 return err;
5358 if (dev->flags != old_flags)
5359 dev_set_rx_mode(dev);
5360 return err;
5361 }
5362 EXPORT_SYMBOL(dev_set_promiscuity);
5363
5364 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5365 {
5366 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5367
5368 ASSERT_RTNL();
5369
5370 dev->flags |= IFF_ALLMULTI;
5371 dev->allmulti += inc;
5372 if (dev->allmulti == 0) {
5373 /*
5374 * Avoid overflow.
5375 * If inc causes overflow, untouch allmulti and return error.
5376 */
5377 if (inc < 0)
5378 dev->flags &= ~IFF_ALLMULTI;
5379 else {
5380 dev->allmulti -= inc;
5381 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5382 dev->name);
5383 return -EOVERFLOW;
5384 }
5385 }
5386 if (dev->flags ^ old_flags) {
5387 dev_change_rx_flags(dev, IFF_ALLMULTI);
5388 dev_set_rx_mode(dev);
5389 if (notify)
5390 __dev_notify_flags(dev, old_flags,
5391 dev->gflags ^ old_gflags);
5392 }
5393 return 0;
5394 }
5395
5396 /**
5397 * dev_set_allmulti - update allmulti count on a device
5398 * @dev: device
5399 * @inc: modifier
5400 *
5401 * Add or remove reception of all multicast frames to a device. While the
5402 * count in the device remains above zero the interface remains listening
5403 * to all interfaces. Once it hits zero the device reverts back to normal
5404 * filtering operation. A negative @inc value is used to drop the counter
5405 * when releasing a resource needing all multicasts.
5406 * Return 0 if successful or a negative errno code on error.
5407 */
5408
5409 int dev_set_allmulti(struct net_device *dev, int inc)
5410 {
5411 return __dev_set_allmulti(dev, inc, true);
5412 }
5413 EXPORT_SYMBOL(dev_set_allmulti);
5414
5415 /*
5416 * Upload unicast and multicast address lists to device and
5417 * configure RX filtering. When the device doesn't support unicast
5418 * filtering it is put in promiscuous mode while unicast addresses
5419 * are present.
5420 */
5421 void __dev_set_rx_mode(struct net_device *dev)
5422 {
5423 const struct net_device_ops *ops = dev->netdev_ops;
5424
5425 /* dev_open will call this function so the list will stay sane. */
5426 if (!(dev->flags&IFF_UP))
5427 return;
5428
5429 if (!netif_device_present(dev))
5430 return;
5431
5432 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5433 /* Unicast addresses changes may only happen under the rtnl,
5434 * therefore calling __dev_set_promiscuity here is safe.
5435 */
5436 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5437 __dev_set_promiscuity(dev, 1, false);
5438 dev->uc_promisc = true;
5439 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5440 __dev_set_promiscuity(dev, -1, false);
5441 dev->uc_promisc = false;
5442 }
5443 }
5444
5445 if (ops->ndo_set_rx_mode)
5446 ops->ndo_set_rx_mode(dev);
5447 }
5448
5449 void dev_set_rx_mode(struct net_device *dev)
5450 {
5451 netif_addr_lock_bh(dev);
5452 __dev_set_rx_mode(dev);
5453 netif_addr_unlock_bh(dev);
5454 }
5455
5456 /**
5457 * dev_get_flags - get flags reported to userspace
5458 * @dev: device
5459 *
5460 * Get the combination of flag bits exported through APIs to userspace.
5461 */
5462 unsigned int dev_get_flags(const struct net_device *dev)
5463 {
5464 unsigned int flags;
5465
5466 flags = (dev->flags & ~(IFF_PROMISC |
5467 IFF_ALLMULTI |
5468 IFF_RUNNING |
5469 IFF_LOWER_UP |
5470 IFF_DORMANT)) |
5471 (dev->gflags & (IFF_PROMISC |
5472 IFF_ALLMULTI));
5473
5474 if (netif_running(dev)) {
5475 if (netif_oper_up(dev))
5476 flags |= IFF_RUNNING;
5477 if (netif_carrier_ok(dev))
5478 flags |= IFF_LOWER_UP;
5479 if (netif_dormant(dev))
5480 flags |= IFF_DORMANT;
5481 }
5482
5483 return flags;
5484 }
5485 EXPORT_SYMBOL(dev_get_flags);
5486
5487 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5488 {
5489 unsigned int old_flags = dev->flags;
5490 int ret;
5491
5492 ASSERT_RTNL();
5493
5494 /*
5495 * Set the flags on our device.
5496 */
5497
5498 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5499 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5500 IFF_AUTOMEDIA)) |
5501 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5502 IFF_ALLMULTI));
5503
5504 /*
5505 * Load in the correct multicast list now the flags have changed.
5506 */
5507
5508 if ((old_flags ^ flags) & IFF_MULTICAST)
5509 dev_change_rx_flags(dev, IFF_MULTICAST);
5510
5511 dev_set_rx_mode(dev);
5512
5513 /*
5514 * Have we downed the interface. We handle IFF_UP ourselves
5515 * according to user attempts to set it, rather than blindly
5516 * setting it.
5517 */
5518
5519 ret = 0;
5520 if ((old_flags ^ flags) & IFF_UP)
5521 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5522
5523 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5524 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5525 unsigned int old_flags = dev->flags;
5526
5527 dev->gflags ^= IFF_PROMISC;
5528
5529 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5530 if (dev->flags != old_flags)
5531 dev_set_rx_mode(dev);
5532 }
5533
5534 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5535 is important. Some (broken) drivers set IFF_PROMISC, when
5536 IFF_ALLMULTI is requested not asking us and not reporting.
5537 */
5538 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5539 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5540
5541 dev->gflags ^= IFF_ALLMULTI;
5542 __dev_set_allmulti(dev, inc, false);
5543 }
5544
5545 return ret;
5546 }
5547
5548 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5549 unsigned int gchanges)
5550 {
5551 unsigned int changes = dev->flags ^ old_flags;
5552
5553 if (gchanges)
5554 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5555
5556 if (changes & IFF_UP) {
5557 if (dev->flags & IFF_UP)
5558 call_netdevice_notifiers(NETDEV_UP, dev);
5559 else
5560 call_netdevice_notifiers(NETDEV_DOWN, dev);
5561 }
5562
5563 if (dev->flags & IFF_UP &&
5564 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5565 struct netdev_notifier_change_info change_info;
5566
5567 change_info.flags_changed = changes;
5568 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5569 &change_info.info);
5570 }
5571 }
5572
5573 /**
5574 * dev_change_flags - change device settings
5575 * @dev: device
5576 * @flags: device state flags
5577 *
5578 * Change settings on device based state flags. The flags are
5579 * in the userspace exported format.
5580 */
5581 int dev_change_flags(struct net_device *dev, unsigned int flags)
5582 {
5583 int ret;
5584 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5585
5586 ret = __dev_change_flags(dev, flags);
5587 if (ret < 0)
5588 return ret;
5589
5590 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5591 __dev_notify_flags(dev, old_flags, changes);
5592 return ret;
5593 }
5594 EXPORT_SYMBOL(dev_change_flags);
5595
5596 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5597 {
5598 const struct net_device_ops *ops = dev->netdev_ops;
5599
5600 if (ops->ndo_change_mtu)
5601 return ops->ndo_change_mtu(dev, new_mtu);
5602
5603 dev->mtu = new_mtu;
5604 return 0;
5605 }
5606
5607 /**
5608 * dev_set_mtu - Change maximum transfer unit
5609 * @dev: device
5610 * @new_mtu: new transfer unit
5611 *
5612 * Change the maximum transfer size of the network device.
5613 */
5614 int dev_set_mtu(struct net_device *dev, int new_mtu)
5615 {
5616 int err, orig_mtu;
5617
5618 if (new_mtu == dev->mtu)
5619 return 0;
5620
5621 /* MTU must be positive. */
5622 if (new_mtu < 0)
5623 return -EINVAL;
5624
5625 if (!netif_device_present(dev))
5626 return -ENODEV;
5627
5628 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
5629 err = notifier_to_errno(err);
5630 if (err)
5631 return err;
5632
5633 orig_mtu = dev->mtu;
5634 err = __dev_set_mtu(dev, new_mtu);
5635
5636 if (!err) {
5637 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5638 err = notifier_to_errno(err);
5639 if (err) {
5640 /* setting mtu back and notifying everyone again,
5641 * so that they have a chance to revert changes.
5642 */
5643 __dev_set_mtu(dev, orig_mtu);
5644 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5645 }
5646 }
5647 return err;
5648 }
5649 EXPORT_SYMBOL(dev_set_mtu);
5650
5651 /**
5652 * dev_set_group - Change group this device belongs to
5653 * @dev: device
5654 * @new_group: group this device should belong to
5655 */
5656 void dev_set_group(struct net_device *dev, int new_group)
5657 {
5658 dev->group = new_group;
5659 }
5660 EXPORT_SYMBOL(dev_set_group);
5661
5662 /**
5663 * dev_set_mac_address - Change Media Access Control Address
5664 * @dev: device
5665 * @sa: new address
5666 *
5667 * Change the hardware (MAC) address of the device
5668 */
5669 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5670 {
5671 const struct net_device_ops *ops = dev->netdev_ops;
5672 int err;
5673
5674 if (!ops->ndo_set_mac_address)
5675 return -EOPNOTSUPP;
5676 if (sa->sa_family != dev->type)
5677 return -EINVAL;
5678 if (!netif_device_present(dev))
5679 return -ENODEV;
5680 err = ops->ndo_set_mac_address(dev, sa);
5681 if (err)
5682 return err;
5683 dev->addr_assign_type = NET_ADDR_SET;
5684 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5685 add_device_randomness(dev->dev_addr, dev->addr_len);
5686 return 0;
5687 }
5688 EXPORT_SYMBOL(dev_set_mac_address);
5689
5690 /**
5691 * dev_change_carrier - Change device carrier
5692 * @dev: device
5693 * @new_carrier: new value
5694 *
5695 * Change device carrier
5696 */
5697 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5698 {
5699 const struct net_device_ops *ops = dev->netdev_ops;
5700
5701 if (!ops->ndo_change_carrier)
5702 return -EOPNOTSUPP;
5703 if (!netif_device_present(dev))
5704 return -ENODEV;
5705 return ops->ndo_change_carrier(dev, new_carrier);
5706 }
5707 EXPORT_SYMBOL(dev_change_carrier);
5708
5709 /**
5710 * dev_get_phys_port_id - Get device physical port ID
5711 * @dev: device
5712 * @ppid: port ID
5713 *
5714 * Get device physical port ID
5715 */
5716 int dev_get_phys_port_id(struct net_device *dev,
5717 struct netdev_phys_port_id *ppid)
5718 {
5719 const struct net_device_ops *ops = dev->netdev_ops;
5720
5721 if (!ops->ndo_get_phys_port_id)
5722 return -EOPNOTSUPP;
5723 return ops->ndo_get_phys_port_id(dev, ppid);
5724 }
5725 EXPORT_SYMBOL(dev_get_phys_port_id);
5726
5727 /**
5728 * dev_new_index - allocate an ifindex
5729 * @net: the applicable net namespace
5730 *
5731 * Returns a suitable unique value for a new device interface
5732 * number. The caller must hold the rtnl semaphore or the
5733 * dev_base_lock to be sure it remains unique.
5734 */
5735 static int dev_new_index(struct net *net)
5736 {
5737 int ifindex = net->ifindex;
5738 for (;;) {
5739 if (++ifindex <= 0)
5740 ifindex = 1;
5741 if (!__dev_get_by_index(net, ifindex))
5742 return net->ifindex = ifindex;
5743 }
5744 }
5745
5746 /* Delayed registration/unregisteration */
5747 static LIST_HEAD(net_todo_list);
5748 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5749
5750 static void net_set_todo(struct net_device *dev)
5751 {
5752 list_add_tail(&dev->todo_list, &net_todo_list);
5753 dev_net(dev)->dev_unreg_count++;
5754 }
5755
5756 static void rollback_registered_many(struct list_head *head)
5757 {
5758 struct net_device *dev, *tmp;
5759 LIST_HEAD(close_head);
5760
5761 BUG_ON(dev_boot_phase);
5762 ASSERT_RTNL();
5763
5764 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5765 /* Some devices call without registering
5766 * for initialization unwind. Remove those
5767 * devices and proceed with the remaining.
5768 */
5769 if (dev->reg_state == NETREG_UNINITIALIZED) {
5770 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5771 dev->name, dev);
5772
5773 WARN_ON(1);
5774 list_del(&dev->unreg_list);
5775 continue;
5776 }
5777 dev->dismantle = true;
5778 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5779 }
5780
5781 /* If device is running, close it first. */
5782 list_for_each_entry(dev, head, unreg_list)
5783 list_add_tail(&dev->close_list, &close_head);
5784 dev_close_many(&close_head);
5785
5786 list_for_each_entry(dev, head, unreg_list) {
5787 /* And unlink it from device chain. */
5788 unlist_netdevice(dev);
5789
5790 dev->reg_state = NETREG_UNREGISTERING;
5791 }
5792
5793 synchronize_net();
5794
5795 list_for_each_entry(dev, head, unreg_list) {
5796 /* Shutdown queueing discipline. */
5797 dev_shutdown(dev);
5798
5799
5800 /* Notify protocols, that we are about to destroy
5801 this device. They should clean all the things.
5802 */
5803 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5804
5805 /*
5806 * Flush the unicast and multicast chains
5807 */
5808 dev_uc_flush(dev);
5809 dev_mc_flush(dev);
5810
5811 if (dev->netdev_ops->ndo_uninit)
5812 dev->netdev_ops->ndo_uninit(dev);
5813
5814 if (!dev->rtnl_link_ops ||
5815 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5816 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5817
5818 /* Notifier chain MUST detach us all upper devices. */
5819 WARN_ON(netdev_has_any_upper_dev(dev));
5820
5821 /* Remove entries from kobject tree */
5822 netdev_unregister_kobject(dev);
5823 #ifdef CONFIG_XPS
5824 /* Remove XPS queueing entries */
5825 netif_reset_xps_queues_gt(dev, 0);
5826 #endif
5827 }
5828
5829 synchronize_net();
5830
5831 list_for_each_entry(dev, head, unreg_list)
5832 dev_put(dev);
5833 }
5834
5835 static void rollback_registered(struct net_device *dev)
5836 {
5837 LIST_HEAD(single);
5838
5839 list_add(&dev->unreg_list, &single);
5840 rollback_registered_many(&single);
5841 list_del(&single);
5842 }
5843
5844 static netdev_features_t netdev_fix_features(struct net_device *dev,
5845 netdev_features_t features)
5846 {
5847 /* Fix illegal checksum combinations */
5848 if ((features & NETIF_F_HW_CSUM) &&
5849 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5850 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5851 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5852 }
5853
5854 /* TSO requires that SG is present as well. */
5855 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5856 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5857 features &= ~NETIF_F_ALL_TSO;
5858 }
5859
5860 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5861 !(features & NETIF_F_IP_CSUM)) {
5862 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5863 features &= ~NETIF_F_TSO;
5864 features &= ~NETIF_F_TSO_ECN;
5865 }
5866
5867 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5868 !(features & NETIF_F_IPV6_CSUM)) {
5869 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5870 features &= ~NETIF_F_TSO6;
5871 }
5872
5873 /* TSO ECN requires that TSO is present as well. */
5874 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5875 features &= ~NETIF_F_TSO_ECN;
5876
5877 /* Software GSO depends on SG. */
5878 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5879 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5880 features &= ~NETIF_F_GSO;
5881 }
5882
5883 /* UFO needs SG and checksumming */
5884 if (features & NETIF_F_UFO) {
5885 /* maybe split UFO into V4 and V6? */
5886 if (!((features & NETIF_F_GEN_CSUM) ||
5887 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5888 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5889 netdev_dbg(dev,
5890 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5891 features &= ~NETIF_F_UFO;
5892 }
5893
5894 if (!(features & NETIF_F_SG)) {
5895 netdev_dbg(dev,
5896 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5897 features &= ~NETIF_F_UFO;
5898 }
5899 }
5900
5901 #ifdef CONFIG_NET_RX_BUSY_POLL
5902 if (dev->netdev_ops->ndo_busy_poll)
5903 features |= NETIF_F_BUSY_POLL;
5904 else
5905 #endif
5906 features &= ~NETIF_F_BUSY_POLL;
5907
5908 return features;
5909 }
5910
5911 int __netdev_update_features(struct net_device *dev)
5912 {
5913 netdev_features_t features;
5914 int err = 0;
5915
5916 ASSERT_RTNL();
5917
5918 features = netdev_get_wanted_features(dev);
5919
5920 if (dev->netdev_ops->ndo_fix_features)
5921 features = dev->netdev_ops->ndo_fix_features(dev, features);
5922
5923 /* driver might be less strict about feature dependencies */
5924 features = netdev_fix_features(dev, features);
5925
5926 if (dev->features == features)
5927 return 0;
5928
5929 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5930 &dev->features, &features);
5931
5932 if (dev->netdev_ops->ndo_set_features)
5933 err = dev->netdev_ops->ndo_set_features(dev, features);
5934
5935 if (unlikely(err < 0)) {
5936 netdev_err(dev,
5937 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5938 err, &features, &dev->features);
5939 return -1;
5940 }
5941
5942 if (!err)
5943 dev->features = features;
5944
5945 return 1;
5946 }
5947
5948 /**
5949 * netdev_update_features - recalculate device features
5950 * @dev: the device to check
5951 *
5952 * Recalculate dev->features set and send notifications if it
5953 * has changed. Should be called after driver or hardware dependent
5954 * conditions might have changed that influence the features.
5955 */
5956 void netdev_update_features(struct net_device *dev)
5957 {
5958 if (__netdev_update_features(dev))
5959 netdev_features_change(dev);
5960 }
5961 EXPORT_SYMBOL(netdev_update_features);
5962
5963 /**
5964 * netdev_change_features - recalculate device features
5965 * @dev: the device to check
5966 *
5967 * Recalculate dev->features set and send notifications even
5968 * if they have not changed. Should be called instead of
5969 * netdev_update_features() if also dev->vlan_features might
5970 * have changed to allow the changes to be propagated to stacked
5971 * VLAN devices.
5972 */
5973 void netdev_change_features(struct net_device *dev)
5974 {
5975 __netdev_update_features(dev);
5976 netdev_features_change(dev);
5977 }
5978 EXPORT_SYMBOL(netdev_change_features);
5979
5980 /**
5981 * netif_stacked_transfer_operstate - transfer operstate
5982 * @rootdev: the root or lower level device to transfer state from
5983 * @dev: the device to transfer operstate to
5984 *
5985 * Transfer operational state from root to device. This is normally
5986 * called when a stacking relationship exists between the root
5987 * device and the device(a leaf device).
5988 */
5989 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5990 struct net_device *dev)
5991 {
5992 if (rootdev->operstate == IF_OPER_DORMANT)
5993 netif_dormant_on(dev);
5994 else
5995 netif_dormant_off(dev);
5996
5997 if (netif_carrier_ok(rootdev)) {
5998 if (!netif_carrier_ok(dev))
5999 netif_carrier_on(dev);
6000 } else {
6001 if (netif_carrier_ok(dev))
6002 netif_carrier_off(dev);
6003 }
6004 }
6005 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
6006
6007 #ifdef CONFIG_SYSFS
6008 static int netif_alloc_rx_queues(struct net_device *dev)
6009 {
6010 unsigned int i, count = dev->num_rx_queues;
6011 struct netdev_rx_queue *rx;
6012
6013 BUG_ON(count < 1);
6014
6015 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
6016 if (!rx)
6017 return -ENOMEM;
6018
6019 dev->_rx = rx;
6020
6021 for (i = 0; i < count; i++)
6022 rx[i].dev = dev;
6023 return 0;
6024 }
6025 #endif
6026
6027 static void netdev_init_one_queue(struct net_device *dev,
6028 struct netdev_queue *queue, void *_unused)
6029 {
6030 /* Initialize queue lock */
6031 spin_lock_init(&queue->_xmit_lock);
6032 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
6033 queue->xmit_lock_owner = -1;
6034 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
6035 queue->dev = dev;
6036 #ifdef CONFIG_BQL
6037 dql_init(&queue->dql, HZ);
6038 #endif
6039 }
6040
6041 static void netif_free_tx_queues(struct net_device *dev)
6042 {
6043 kvfree(dev->_tx);
6044 }
6045
6046 static int netif_alloc_netdev_queues(struct net_device *dev)
6047 {
6048 unsigned int count = dev->num_tx_queues;
6049 struct netdev_queue *tx;
6050 size_t sz = count * sizeof(*tx);
6051
6052 BUG_ON(count < 1 || count > 0xffff);
6053
6054 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6055 if (!tx) {
6056 tx = vzalloc(sz);
6057 if (!tx)
6058 return -ENOMEM;
6059 }
6060 dev->_tx = tx;
6061
6062 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
6063 spin_lock_init(&dev->tx_global_lock);
6064
6065 return 0;
6066 }
6067
6068 /**
6069 * register_netdevice - register a network device
6070 * @dev: device to register
6071 *
6072 * Take a completed network device structure and add it to the kernel
6073 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6074 * chain. 0 is returned on success. A negative errno code is returned
6075 * on a failure to set up the device, or if the name is a duplicate.
6076 *
6077 * Callers must hold the rtnl semaphore. You may want
6078 * register_netdev() instead of this.
6079 *
6080 * BUGS:
6081 * The locking appears insufficient to guarantee two parallel registers
6082 * will not get the same name.
6083 */
6084
6085 int register_netdevice(struct net_device *dev)
6086 {
6087 int ret;
6088 struct net *net = dev_net(dev);
6089
6090 BUG_ON(dev_boot_phase);
6091 ASSERT_RTNL();
6092
6093 might_sleep();
6094
6095 /* When net_device's are persistent, this will be fatal. */
6096 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
6097 BUG_ON(!net);
6098
6099 spin_lock_init(&dev->addr_list_lock);
6100 netdev_set_addr_lockdep_class(dev);
6101
6102 dev->iflink = -1;
6103
6104 ret = dev_get_valid_name(net, dev, dev->name);
6105 if (ret < 0)
6106 goto out;
6107
6108 /* Init, if this function is available */
6109 if (dev->netdev_ops->ndo_init) {
6110 ret = dev->netdev_ops->ndo_init(dev);
6111 if (ret) {
6112 if (ret > 0)
6113 ret = -EIO;
6114 goto out;
6115 }
6116 }
6117
6118 if (((dev->hw_features | dev->features) &
6119 NETIF_F_HW_VLAN_CTAG_FILTER) &&
6120 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
6121 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
6122 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
6123 ret = -EINVAL;
6124 goto err_uninit;
6125 }
6126
6127 ret = -EBUSY;
6128 if (!dev->ifindex)
6129 dev->ifindex = dev_new_index(net);
6130 else if (__dev_get_by_index(net, dev->ifindex))
6131 goto err_uninit;
6132
6133 if (dev->iflink == -1)
6134 dev->iflink = dev->ifindex;
6135
6136 /* Transfer changeable features to wanted_features and enable
6137 * software offloads (GSO and GRO).
6138 */
6139 dev->hw_features |= NETIF_F_SOFT_FEATURES;
6140 dev->features |= NETIF_F_SOFT_FEATURES;
6141 dev->wanted_features = dev->features & dev->hw_features;
6142
6143 if (!(dev->flags & IFF_LOOPBACK)) {
6144 dev->hw_features |= NETIF_F_NOCACHE_COPY;
6145 }
6146
6147 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6148 */
6149 dev->vlan_features |= NETIF_F_HIGHDMA;
6150
6151 /* Make NETIF_F_SG inheritable to tunnel devices.
6152 */
6153 dev->hw_enc_features |= NETIF_F_SG;
6154
6155 /* Make NETIF_F_SG inheritable to MPLS.
6156 */
6157 dev->mpls_features |= NETIF_F_SG;
6158
6159 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
6160 ret = notifier_to_errno(ret);
6161 if (ret)
6162 goto err_uninit;
6163
6164 ret = netdev_register_kobject(dev);
6165 if (ret)
6166 goto err_uninit;
6167 dev->reg_state = NETREG_REGISTERED;
6168
6169 __netdev_update_features(dev);
6170
6171 /*
6172 * Default initial state at registry is that the
6173 * device is present.
6174 */
6175
6176 set_bit(__LINK_STATE_PRESENT, &dev->state);
6177
6178 linkwatch_init_dev(dev);
6179
6180 dev_init_scheduler(dev);
6181 dev_hold(dev);
6182 list_netdevice(dev);
6183 add_device_randomness(dev->dev_addr, dev->addr_len);
6184
6185 /* If the device has permanent device address, driver should
6186 * set dev_addr and also addr_assign_type should be set to
6187 * NET_ADDR_PERM (default value).
6188 */
6189 if (dev->addr_assign_type == NET_ADDR_PERM)
6190 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
6191
6192 /* Notify protocols, that a new device appeared. */
6193 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6194 ret = notifier_to_errno(ret);
6195 if (ret) {
6196 rollback_registered(dev);
6197 dev->reg_state = NETREG_UNREGISTERED;
6198 }
6199 /*
6200 * Prevent userspace races by waiting until the network
6201 * device is fully setup before sending notifications.
6202 */
6203 if (!dev->rtnl_link_ops ||
6204 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6205 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6206
6207 out:
6208 return ret;
6209
6210 err_uninit:
6211 if (dev->netdev_ops->ndo_uninit)
6212 dev->netdev_ops->ndo_uninit(dev);
6213 goto out;
6214 }
6215 EXPORT_SYMBOL(register_netdevice);
6216
6217 /**
6218 * init_dummy_netdev - init a dummy network device for NAPI
6219 * @dev: device to init
6220 *
6221 * This takes a network device structure and initialize the minimum
6222 * amount of fields so it can be used to schedule NAPI polls without
6223 * registering a full blown interface. This is to be used by drivers
6224 * that need to tie several hardware interfaces to a single NAPI
6225 * poll scheduler due to HW limitations.
6226 */
6227 int init_dummy_netdev(struct net_device *dev)
6228 {
6229 /* Clear everything. Note we don't initialize spinlocks
6230 * are they aren't supposed to be taken by any of the
6231 * NAPI code and this dummy netdev is supposed to be
6232 * only ever used for NAPI polls
6233 */
6234 memset(dev, 0, sizeof(struct net_device));
6235
6236 /* make sure we BUG if trying to hit standard
6237 * register/unregister code path
6238 */
6239 dev->reg_state = NETREG_DUMMY;
6240
6241 /* NAPI wants this */
6242 INIT_LIST_HEAD(&dev->napi_list);
6243
6244 /* a dummy interface is started by default */
6245 set_bit(__LINK_STATE_PRESENT, &dev->state);
6246 set_bit(__LINK_STATE_START, &dev->state);
6247
6248 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6249 * because users of this 'device' dont need to change
6250 * its refcount.
6251 */
6252
6253 return 0;
6254 }
6255 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6256
6257
6258 /**
6259 * register_netdev - register a network device
6260 * @dev: device to register
6261 *
6262 * Take a completed network device structure and add it to the kernel
6263 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6264 * chain. 0 is returned on success. A negative errno code is returned
6265 * on a failure to set up the device, or if the name is a duplicate.
6266 *
6267 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6268 * and expands the device name if you passed a format string to
6269 * alloc_netdev.
6270 */
6271 int register_netdev(struct net_device *dev)
6272 {
6273 int err;
6274
6275 rtnl_lock();
6276 err = register_netdevice(dev);
6277 rtnl_unlock();
6278 return err;
6279 }
6280 EXPORT_SYMBOL(register_netdev);
6281
6282 int netdev_refcnt_read(const struct net_device *dev)
6283 {
6284 int i, refcnt = 0;
6285
6286 for_each_possible_cpu(i)
6287 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6288 return refcnt;
6289 }
6290 EXPORT_SYMBOL(netdev_refcnt_read);
6291
6292 /**
6293 * netdev_wait_allrefs - wait until all references are gone.
6294 * @dev: target net_device
6295 *
6296 * This is called when unregistering network devices.
6297 *
6298 * Any protocol or device that holds a reference should register
6299 * for netdevice notification, and cleanup and put back the
6300 * reference if they receive an UNREGISTER event.
6301 * We can get stuck here if buggy protocols don't correctly
6302 * call dev_put.
6303 */
6304 static void netdev_wait_allrefs(struct net_device *dev)
6305 {
6306 unsigned long rebroadcast_time, warning_time;
6307 int refcnt;
6308
6309 linkwatch_forget_dev(dev);
6310
6311 rebroadcast_time = warning_time = jiffies;
6312 refcnt = netdev_refcnt_read(dev);
6313
6314 while (refcnt != 0) {
6315 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6316 rtnl_lock();
6317
6318 /* Rebroadcast unregister notification */
6319 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6320
6321 __rtnl_unlock();
6322 rcu_barrier();
6323 rtnl_lock();
6324
6325 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6326 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6327 &dev->state)) {
6328 /* We must not have linkwatch events
6329 * pending on unregister. If this
6330 * happens, we simply run the queue
6331 * unscheduled, resulting in a noop
6332 * for this device.
6333 */
6334 linkwatch_run_queue();
6335 }
6336
6337 __rtnl_unlock();
6338
6339 rebroadcast_time = jiffies;
6340 }
6341
6342 msleep(250);
6343
6344 refcnt = netdev_refcnt_read(dev);
6345
6346 if (time_after(jiffies, warning_time + 10 * HZ)) {
6347 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6348 dev->name, refcnt);
6349 warning_time = jiffies;
6350 }
6351 }
6352 }
6353
6354 /* The sequence is:
6355 *
6356 * rtnl_lock();
6357 * ...
6358 * register_netdevice(x1);
6359 * register_netdevice(x2);
6360 * ...
6361 * unregister_netdevice(y1);
6362 * unregister_netdevice(y2);
6363 * ...
6364 * rtnl_unlock();
6365 * free_netdev(y1);
6366 * free_netdev(y2);
6367 *
6368 * We are invoked by rtnl_unlock().
6369 * This allows us to deal with problems:
6370 * 1) We can delete sysfs objects which invoke hotplug
6371 * without deadlocking with linkwatch via keventd.
6372 * 2) Since we run with the RTNL semaphore not held, we can sleep
6373 * safely in order to wait for the netdev refcnt to drop to zero.
6374 *
6375 * We must not return until all unregister events added during
6376 * the interval the lock was held have been completed.
6377 */
6378 void netdev_run_todo(void)
6379 {
6380 struct list_head list;
6381
6382 /* Snapshot list, allow later requests */
6383 list_replace_init(&net_todo_list, &list);
6384
6385 __rtnl_unlock();
6386
6387
6388 /* Wait for rcu callbacks to finish before next phase */
6389 if (!list_empty(&list))
6390 rcu_barrier();
6391
6392 while (!list_empty(&list)) {
6393 struct net_device *dev
6394 = list_first_entry(&list, struct net_device, todo_list);
6395 list_del(&dev->todo_list);
6396
6397 rtnl_lock();
6398 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6399 __rtnl_unlock();
6400
6401 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6402 pr_err("network todo '%s' but state %d\n",
6403 dev->name, dev->reg_state);
6404 dump_stack();
6405 continue;
6406 }
6407
6408 dev->reg_state = NETREG_UNREGISTERED;
6409
6410 on_each_cpu(flush_backlog, dev, 1);
6411
6412 netdev_wait_allrefs(dev);
6413
6414 /* paranoia */
6415 BUG_ON(netdev_refcnt_read(dev));
6416 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6417 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6418 WARN_ON(dev->dn_ptr);
6419
6420 if (dev->destructor)
6421 dev->destructor(dev);
6422
6423 /* Report a network device has been unregistered */
6424 rtnl_lock();
6425 dev_net(dev)->dev_unreg_count--;
6426 __rtnl_unlock();
6427 wake_up(&netdev_unregistering_wq);
6428
6429 /* Free network device */
6430 kobject_put(&dev->dev.kobj);
6431 }
6432 }
6433
6434 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6435 * fields in the same order, with only the type differing.
6436 */
6437 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6438 const struct net_device_stats *netdev_stats)
6439 {
6440 #if BITS_PER_LONG == 64
6441 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6442 memcpy(stats64, netdev_stats, sizeof(*stats64));
6443 #else
6444 size_t i, n = sizeof(*stats64) / sizeof(u64);
6445 const unsigned long *src = (const unsigned long *)netdev_stats;
6446 u64 *dst = (u64 *)stats64;
6447
6448 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6449 sizeof(*stats64) / sizeof(u64));
6450 for (i = 0; i < n; i++)
6451 dst[i] = src[i];
6452 #endif
6453 }
6454 EXPORT_SYMBOL(netdev_stats_to_stats64);
6455
6456 /**
6457 * dev_get_stats - get network device statistics
6458 * @dev: device to get statistics from
6459 * @storage: place to store stats
6460 *
6461 * Get network statistics from device. Return @storage.
6462 * The device driver may provide its own method by setting
6463 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6464 * otherwise the internal statistics structure is used.
6465 */
6466 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6467 struct rtnl_link_stats64 *storage)
6468 {
6469 const struct net_device_ops *ops = dev->netdev_ops;
6470
6471 if (ops->ndo_get_stats64) {
6472 memset(storage, 0, sizeof(*storage));
6473 ops->ndo_get_stats64(dev, storage);
6474 } else if (ops->ndo_get_stats) {
6475 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6476 } else {
6477 netdev_stats_to_stats64(storage, &dev->stats);
6478 }
6479 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6480 storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6481 return storage;
6482 }
6483 EXPORT_SYMBOL(dev_get_stats);
6484
6485 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6486 {
6487 struct netdev_queue *queue = dev_ingress_queue(dev);
6488
6489 #ifdef CONFIG_NET_CLS_ACT
6490 if (queue)
6491 return queue;
6492 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6493 if (!queue)
6494 return NULL;
6495 netdev_init_one_queue(dev, queue, NULL);
6496 queue->qdisc = &noop_qdisc;
6497 queue->qdisc_sleeping = &noop_qdisc;
6498 rcu_assign_pointer(dev->ingress_queue, queue);
6499 #endif
6500 return queue;
6501 }
6502
6503 static const struct ethtool_ops default_ethtool_ops;
6504
6505 void netdev_set_default_ethtool_ops(struct net_device *dev,
6506 const struct ethtool_ops *ops)
6507 {
6508 if (dev->ethtool_ops == &default_ethtool_ops)
6509 dev->ethtool_ops = ops;
6510 }
6511 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6512
6513 void netdev_freemem(struct net_device *dev)
6514 {
6515 char *addr = (char *)dev - dev->padded;
6516
6517 kvfree(addr);
6518 }
6519
6520 /**
6521 * alloc_netdev_mqs - allocate network device
6522 * @sizeof_priv: size of private data to allocate space for
6523 * @name: device name format string
6524 * @name_assign_type: origin of device name
6525 * @setup: callback to initialize device
6526 * @txqs: the number of TX subqueues to allocate
6527 * @rxqs: the number of RX subqueues to allocate
6528 *
6529 * Allocates a struct net_device with private data area for driver use
6530 * and performs basic initialization. Also allocates subqueue structs
6531 * for each queue on the device.
6532 */
6533 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6534 unsigned char name_assign_type,
6535 void (*setup)(struct net_device *),
6536 unsigned int txqs, unsigned int rxqs)
6537 {
6538 struct net_device *dev;
6539 size_t alloc_size;
6540 struct net_device *p;
6541
6542 BUG_ON(strlen(name) >= sizeof(dev->name));
6543
6544 if (txqs < 1) {
6545 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6546 return NULL;
6547 }
6548
6549 #ifdef CONFIG_SYSFS
6550 if (rxqs < 1) {
6551 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6552 return NULL;
6553 }
6554 #endif
6555
6556 alloc_size = sizeof(struct net_device);
6557 if (sizeof_priv) {
6558 /* ensure 32-byte alignment of private area */
6559 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6560 alloc_size += sizeof_priv;
6561 }
6562 /* ensure 32-byte alignment of whole construct */
6563 alloc_size += NETDEV_ALIGN - 1;
6564
6565 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6566 if (!p)
6567 p = vzalloc(alloc_size);
6568 if (!p)
6569 return NULL;
6570
6571 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6572 dev->padded = (char *)dev - (char *)p;
6573
6574 dev->pcpu_refcnt = alloc_percpu(int);
6575 if (!dev->pcpu_refcnt)
6576 goto free_dev;
6577
6578 if (dev_addr_init(dev))
6579 goto free_pcpu;
6580
6581 dev_mc_init(dev);
6582 dev_uc_init(dev);
6583
6584 dev_net_set(dev, &init_net);
6585
6586 dev->gso_max_size = GSO_MAX_SIZE;
6587 dev->gso_max_segs = GSO_MAX_SEGS;
6588
6589 INIT_LIST_HEAD(&dev->napi_list);
6590 INIT_LIST_HEAD(&dev->unreg_list);
6591 INIT_LIST_HEAD(&dev->close_list);
6592 INIT_LIST_HEAD(&dev->link_watch_list);
6593 INIT_LIST_HEAD(&dev->adj_list.upper);
6594 INIT_LIST_HEAD(&dev->adj_list.lower);
6595 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6596 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6597 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6598 setup(dev);
6599
6600 dev->num_tx_queues = txqs;
6601 dev->real_num_tx_queues = txqs;
6602 if (netif_alloc_netdev_queues(dev))
6603 goto free_all;
6604
6605 #ifdef CONFIG_SYSFS
6606 dev->num_rx_queues = rxqs;
6607 dev->real_num_rx_queues = rxqs;
6608 if (netif_alloc_rx_queues(dev))
6609 goto free_all;
6610 #endif
6611
6612 strcpy(dev->name, name);
6613 dev->name_assign_type = name_assign_type;
6614 dev->group = INIT_NETDEV_GROUP;
6615 if (!dev->ethtool_ops)
6616 dev->ethtool_ops = &default_ethtool_ops;
6617 return dev;
6618
6619 free_all:
6620 free_netdev(dev);
6621 return NULL;
6622
6623 free_pcpu:
6624 free_percpu(dev->pcpu_refcnt);
6625 free_dev:
6626 netdev_freemem(dev);
6627 return NULL;
6628 }
6629 EXPORT_SYMBOL(alloc_netdev_mqs);
6630
6631 /**
6632 * free_netdev - free network device
6633 * @dev: device
6634 *
6635 * This function does the last stage of destroying an allocated device
6636 * interface. The reference to the device object is released.
6637 * If this is the last reference then it will be freed.
6638 */
6639 void free_netdev(struct net_device *dev)
6640 {
6641 struct napi_struct *p, *n;
6642
6643 release_net(dev_net(dev));
6644
6645 netif_free_tx_queues(dev);
6646 #ifdef CONFIG_SYSFS
6647 kfree(dev->_rx);
6648 #endif
6649
6650 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6651
6652 /* Flush device addresses */
6653 dev_addr_flush(dev);
6654
6655 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6656 netif_napi_del(p);
6657
6658 free_percpu(dev->pcpu_refcnt);
6659 dev->pcpu_refcnt = NULL;
6660
6661 /* Compatibility with error handling in drivers */
6662 if (dev->reg_state == NETREG_UNINITIALIZED) {
6663 netdev_freemem(dev);
6664 return;
6665 }
6666
6667 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6668 dev->reg_state = NETREG_RELEASED;
6669
6670 /* will free via device release */
6671 put_device(&dev->dev);
6672 }
6673 EXPORT_SYMBOL(free_netdev);
6674
6675 /**
6676 * synchronize_net - Synchronize with packet receive processing
6677 *
6678 * Wait for packets currently being received to be done.
6679 * Does not block later packets from starting.
6680 */
6681 void synchronize_net(void)
6682 {
6683 might_sleep();
6684 if (rtnl_is_locked())
6685 synchronize_rcu_expedited();
6686 else
6687 synchronize_rcu();
6688 }
6689 EXPORT_SYMBOL(synchronize_net);
6690
6691 /**
6692 * unregister_netdevice_queue - remove device from the kernel
6693 * @dev: device
6694 * @head: list
6695 *
6696 * This function shuts down a device interface and removes it
6697 * from the kernel tables.
6698 * If head not NULL, device is queued to be unregistered later.
6699 *
6700 * Callers must hold the rtnl semaphore. You may want
6701 * unregister_netdev() instead of this.
6702 */
6703
6704 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6705 {
6706 ASSERT_RTNL();
6707
6708 if (head) {
6709 list_move_tail(&dev->unreg_list, head);
6710 } else {
6711 rollback_registered(dev);
6712 /* Finish processing unregister after unlock */
6713 net_set_todo(dev);
6714 }
6715 }
6716 EXPORT_SYMBOL(unregister_netdevice_queue);
6717
6718 /**
6719 * unregister_netdevice_many - unregister many devices
6720 * @head: list of devices
6721 *
6722 * Note: As most callers use a stack allocated list_head,
6723 * we force a list_del() to make sure stack wont be corrupted later.
6724 */
6725 void unregister_netdevice_many(struct list_head *head)
6726 {
6727 struct net_device *dev;
6728
6729 if (!list_empty(head)) {
6730 rollback_registered_many(head);
6731 list_for_each_entry(dev, head, unreg_list)
6732 net_set_todo(dev);
6733 list_del(head);
6734 }
6735 }
6736 EXPORT_SYMBOL(unregister_netdevice_many);
6737
6738 /**
6739 * unregister_netdev - remove device from the kernel
6740 * @dev: device
6741 *
6742 * This function shuts down a device interface and removes it
6743 * from the kernel tables.
6744 *
6745 * This is just a wrapper for unregister_netdevice that takes
6746 * the rtnl semaphore. In general you want to use this and not
6747 * unregister_netdevice.
6748 */
6749 void unregister_netdev(struct net_device *dev)
6750 {
6751 rtnl_lock();
6752 unregister_netdevice(dev);
6753 rtnl_unlock();
6754 }
6755 EXPORT_SYMBOL(unregister_netdev);
6756
6757 /**
6758 * dev_change_net_namespace - move device to different nethost namespace
6759 * @dev: device
6760 * @net: network namespace
6761 * @pat: If not NULL name pattern to try if the current device name
6762 * is already taken in the destination network namespace.
6763 *
6764 * This function shuts down a device interface and moves it
6765 * to a new network namespace. On success 0 is returned, on
6766 * a failure a netagive errno code is returned.
6767 *
6768 * Callers must hold the rtnl semaphore.
6769 */
6770
6771 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6772 {
6773 int err;
6774
6775 ASSERT_RTNL();
6776
6777 /* Don't allow namespace local devices to be moved. */
6778 err = -EINVAL;
6779 if (dev->features & NETIF_F_NETNS_LOCAL)
6780 goto out;
6781
6782 /* Ensure the device has been registrered */
6783 if (dev->reg_state != NETREG_REGISTERED)
6784 goto out;
6785
6786 /* Get out if there is nothing todo */
6787 err = 0;
6788 if (net_eq(dev_net(dev), net))
6789 goto out;
6790
6791 /* Pick the destination device name, and ensure
6792 * we can use it in the destination network namespace.
6793 */
6794 err = -EEXIST;
6795 if (__dev_get_by_name(net, dev->name)) {
6796 /* We get here if we can't use the current device name */
6797 if (!pat)
6798 goto out;
6799 if (dev_get_valid_name(net, dev, pat) < 0)
6800 goto out;
6801 }
6802
6803 /*
6804 * And now a mini version of register_netdevice unregister_netdevice.
6805 */
6806
6807 /* If device is running close it first. */
6808 dev_close(dev);
6809
6810 /* And unlink it from device chain */
6811 err = -ENODEV;
6812 unlist_netdevice(dev);
6813
6814 synchronize_net();
6815
6816 /* Shutdown queueing discipline. */
6817 dev_shutdown(dev);
6818
6819 /* Notify protocols, that we are about to destroy
6820 this device. They should clean all the things.
6821
6822 Note that dev->reg_state stays at NETREG_REGISTERED.
6823 This is wanted because this way 8021q and macvlan know
6824 the device is just moving and can keep their slaves up.
6825 */
6826 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6827 rcu_barrier();
6828 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6829 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6830
6831 /*
6832 * Flush the unicast and multicast chains
6833 */
6834 dev_uc_flush(dev);
6835 dev_mc_flush(dev);
6836
6837 /* Send a netdev-removed uevent to the old namespace */
6838 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6839 netdev_adjacent_del_links(dev);
6840
6841 /* Actually switch the network namespace */
6842 dev_net_set(dev, net);
6843
6844 /* If there is an ifindex conflict assign a new one */
6845 if (__dev_get_by_index(net, dev->ifindex)) {
6846 int iflink = (dev->iflink == dev->ifindex);
6847 dev->ifindex = dev_new_index(net);
6848 if (iflink)
6849 dev->iflink = dev->ifindex;
6850 }
6851
6852 /* Send a netdev-add uevent to the new namespace */
6853 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6854 netdev_adjacent_add_links(dev);
6855
6856 /* Fixup kobjects */
6857 err = device_rename(&dev->dev, dev->name);
6858 WARN_ON(err);
6859
6860 /* Add the device back in the hashes */
6861 list_netdevice(dev);
6862
6863 /* Notify protocols, that a new device appeared. */
6864 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6865
6866 /*
6867 * Prevent userspace races by waiting until the network
6868 * device is fully setup before sending notifications.
6869 */
6870 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6871
6872 synchronize_net();
6873 err = 0;
6874 out:
6875 return err;
6876 }
6877 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6878
6879 static int dev_cpu_callback(struct notifier_block *nfb,
6880 unsigned long action,
6881 void *ocpu)
6882 {
6883 struct sk_buff **list_skb;
6884 struct sk_buff *skb;
6885 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6886 struct softnet_data *sd, *oldsd;
6887
6888 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6889 return NOTIFY_OK;
6890
6891 local_irq_disable();
6892 cpu = smp_processor_id();
6893 sd = &per_cpu(softnet_data, cpu);
6894 oldsd = &per_cpu(softnet_data, oldcpu);
6895
6896 /* Find end of our completion_queue. */
6897 list_skb = &sd->completion_queue;
6898 while (*list_skb)
6899 list_skb = &(*list_skb)->next;
6900 /* Append completion queue from offline CPU. */
6901 *list_skb = oldsd->completion_queue;
6902 oldsd->completion_queue = NULL;
6903
6904 /* Append output queue from offline CPU. */
6905 if (oldsd->output_queue) {
6906 *sd->output_queue_tailp = oldsd->output_queue;
6907 sd->output_queue_tailp = oldsd->output_queue_tailp;
6908 oldsd->output_queue = NULL;
6909 oldsd->output_queue_tailp = &oldsd->output_queue;
6910 }
6911 /* Append NAPI poll list from offline CPU. */
6912 if (!list_empty(&oldsd->poll_list)) {
6913 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6914 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6915 }
6916
6917 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6918 local_irq_enable();
6919
6920 /* Process offline CPU's input_pkt_queue */
6921 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6922 netif_rx_internal(skb);
6923 input_queue_head_incr(oldsd);
6924 }
6925 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6926 netif_rx_internal(skb);
6927 input_queue_head_incr(oldsd);
6928 }
6929
6930 return NOTIFY_OK;
6931 }
6932
6933
6934 /**
6935 * netdev_increment_features - increment feature set by one
6936 * @all: current feature set
6937 * @one: new feature set
6938 * @mask: mask feature set
6939 *
6940 * Computes a new feature set after adding a device with feature set
6941 * @one to the master device with current feature set @all. Will not
6942 * enable anything that is off in @mask. Returns the new feature set.
6943 */
6944 netdev_features_t netdev_increment_features(netdev_features_t all,
6945 netdev_features_t one, netdev_features_t mask)
6946 {
6947 if (mask & NETIF_F_GEN_CSUM)
6948 mask |= NETIF_F_ALL_CSUM;
6949 mask |= NETIF_F_VLAN_CHALLENGED;
6950
6951 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6952 all &= one | ~NETIF_F_ALL_FOR_ALL;
6953
6954 /* If one device supports hw checksumming, set for all. */
6955 if (all & NETIF_F_GEN_CSUM)
6956 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6957
6958 return all;
6959 }
6960 EXPORT_SYMBOL(netdev_increment_features);
6961
6962 static struct hlist_head * __net_init netdev_create_hash(void)
6963 {
6964 int i;
6965 struct hlist_head *hash;
6966
6967 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6968 if (hash != NULL)
6969 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6970 INIT_HLIST_HEAD(&hash[i]);
6971
6972 return hash;
6973 }
6974
6975 /* Initialize per network namespace state */
6976 static int __net_init netdev_init(struct net *net)
6977 {
6978 if (net != &init_net)
6979 INIT_LIST_HEAD(&net->dev_base_head);
6980
6981 net->dev_name_head = netdev_create_hash();
6982 if (net->dev_name_head == NULL)
6983 goto err_name;
6984
6985 net->dev_index_head = netdev_create_hash();
6986 if (net->dev_index_head == NULL)
6987 goto err_idx;
6988
6989 return 0;
6990
6991 err_idx:
6992 kfree(net->dev_name_head);
6993 err_name:
6994 return -ENOMEM;
6995 }
6996
6997 /**
6998 * netdev_drivername - network driver for the device
6999 * @dev: network device
7000 *
7001 * Determine network driver for device.
7002 */
7003 const char *netdev_drivername(const struct net_device *dev)
7004 {
7005 const struct device_driver *driver;
7006 const struct device *parent;
7007 const char *empty = "";
7008
7009 parent = dev->dev.parent;
7010 if (!parent)
7011 return empty;
7012
7013 driver = parent->driver;
7014 if (driver && driver->name)
7015 return driver->name;
7016 return empty;
7017 }
7018
7019 static int __netdev_printk(const char *level, const struct net_device *dev,
7020 struct va_format *vaf)
7021 {
7022 int r;
7023
7024 if (dev && dev->dev.parent) {
7025 r = dev_printk_emit(level[1] - '0',
7026 dev->dev.parent,
7027 "%s %s %s%s: %pV",
7028 dev_driver_string(dev->dev.parent),
7029 dev_name(dev->dev.parent),
7030 netdev_name(dev), netdev_reg_state(dev),
7031 vaf);
7032 } else if (dev) {
7033 r = printk("%s%s%s: %pV", level, netdev_name(dev),
7034 netdev_reg_state(dev), vaf);
7035 } else {
7036 r = printk("%s(NULL net_device): %pV", level, vaf);
7037 }
7038
7039 return r;
7040 }
7041
7042 int netdev_printk(const char *level, const struct net_device *dev,
7043 const char *format, ...)
7044 {
7045 struct va_format vaf;
7046 va_list args;
7047 int r;
7048
7049 va_start(args, format);
7050
7051 vaf.fmt = format;
7052 vaf.va = &args;
7053
7054 r = __netdev_printk(level, dev, &vaf);
7055
7056 va_end(args);
7057
7058 return r;
7059 }
7060 EXPORT_SYMBOL(netdev_printk);
7061
7062 #define define_netdev_printk_level(func, level) \
7063 int func(const struct net_device *dev, const char *fmt, ...) \
7064 { \
7065 int r; \
7066 struct va_format vaf; \
7067 va_list args; \
7068 \
7069 va_start(args, fmt); \
7070 \
7071 vaf.fmt = fmt; \
7072 vaf.va = &args; \
7073 \
7074 r = __netdev_printk(level, dev, &vaf); \
7075 \
7076 va_end(args); \
7077 \
7078 return r; \
7079 } \
7080 EXPORT_SYMBOL(func);
7081
7082 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
7083 define_netdev_printk_level(netdev_alert, KERN_ALERT);
7084 define_netdev_printk_level(netdev_crit, KERN_CRIT);
7085 define_netdev_printk_level(netdev_err, KERN_ERR);
7086 define_netdev_printk_level(netdev_warn, KERN_WARNING);
7087 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
7088 define_netdev_printk_level(netdev_info, KERN_INFO);
7089
7090 static void __net_exit netdev_exit(struct net *net)
7091 {
7092 kfree(net->dev_name_head);
7093 kfree(net->dev_index_head);
7094 }
7095
7096 static struct pernet_operations __net_initdata netdev_net_ops = {
7097 .init = netdev_init,
7098 .exit = netdev_exit,
7099 };
7100
7101 static void __net_exit default_device_exit(struct net *net)
7102 {
7103 struct net_device *dev, *aux;
7104 /*
7105 * Push all migratable network devices back to the
7106 * initial network namespace
7107 */
7108 rtnl_lock();
7109 for_each_netdev_safe(net, dev, aux) {
7110 int err;
7111 char fb_name[IFNAMSIZ];
7112
7113 /* Ignore unmoveable devices (i.e. loopback) */
7114 if (dev->features & NETIF_F_NETNS_LOCAL)
7115 continue;
7116
7117 /* Leave virtual devices for the generic cleanup */
7118 if (dev->rtnl_link_ops)
7119 continue;
7120
7121 /* Push remaining network devices to init_net */
7122 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
7123 err = dev_change_net_namespace(dev, &init_net, fb_name);
7124 if (err) {
7125 pr_emerg("%s: failed to move %s to init_net: %d\n",
7126 __func__, dev->name, err);
7127 BUG();
7128 }
7129 }
7130 rtnl_unlock();
7131 }
7132
7133 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
7134 {
7135 /* Return with the rtnl_lock held when there are no network
7136 * devices unregistering in any network namespace in net_list.
7137 */
7138 struct net *net;
7139 bool unregistering;
7140 DEFINE_WAIT(wait);
7141
7142 for (;;) {
7143 prepare_to_wait(&netdev_unregistering_wq, &wait,
7144 TASK_UNINTERRUPTIBLE);
7145 unregistering = false;
7146 rtnl_lock();
7147 list_for_each_entry(net, net_list, exit_list) {
7148 if (net->dev_unreg_count > 0) {
7149 unregistering = true;
7150 break;
7151 }
7152 }
7153 if (!unregistering)
7154 break;
7155 __rtnl_unlock();
7156 schedule();
7157 }
7158 finish_wait(&netdev_unregistering_wq, &wait);
7159 }
7160
7161 static void __net_exit default_device_exit_batch(struct list_head *net_list)
7162 {
7163 /* At exit all network devices most be removed from a network
7164 * namespace. Do this in the reverse order of registration.
7165 * Do this across as many network namespaces as possible to
7166 * improve batching efficiency.
7167 */
7168 struct net_device *dev;
7169 struct net *net;
7170 LIST_HEAD(dev_kill_list);
7171
7172 /* To prevent network device cleanup code from dereferencing
7173 * loopback devices or network devices that have been freed
7174 * wait here for all pending unregistrations to complete,
7175 * before unregistring the loopback device and allowing the
7176 * network namespace be freed.
7177 *
7178 * The netdev todo list containing all network devices
7179 * unregistrations that happen in default_device_exit_batch
7180 * will run in the rtnl_unlock() at the end of
7181 * default_device_exit_batch.
7182 */
7183 rtnl_lock_unregistering(net_list);
7184 list_for_each_entry(net, net_list, exit_list) {
7185 for_each_netdev_reverse(net, dev) {
7186 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
7187 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
7188 else
7189 unregister_netdevice_queue(dev, &dev_kill_list);
7190 }
7191 }
7192 unregister_netdevice_many(&dev_kill_list);
7193 rtnl_unlock();
7194 }
7195
7196 static struct pernet_operations __net_initdata default_device_ops = {
7197 .exit = default_device_exit,
7198 .exit_batch = default_device_exit_batch,
7199 };
7200
7201 /*
7202 * Initialize the DEV module. At boot time this walks the device list and
7203 * unhooks any devices that fail to initialise (normally hardware not
7204 * present) and leaves us with a valid list of present and active devices.
7205 *
7206 */
7207
7208 /*
7209 * This is called single threaded during boot, so no need
7210 * to take the rtnl semaphore.
7211 */
7212 static int __init net_dev_init(void)
7213 {
7214 int i, rc = -ENOMEM;
7215
7216 BUG_ON(!dev_boot_phase);
7217
7218 if (dev_proc_init())
7219 goto out;
7220
7221 if (netdev_kobject_init())
7222 goto out;
7223
7224 INIT_LIST_HEAD(&ptype_all);
7225 for (i = 0; i < PTYPE_HASH_SIZE; i++)
7226 INIT_LIST_HEAD(&ptype_base[i]);
7227
7228 INIT_LIST_HEAD(&offload_base);
7229
7230 if (register_pernet_subsys(&netdev_net_ops))
7231 goto out;
7232
7233 /*
7234 * Initialise the packet receive queues.
7235 */
7236
7237 for_each_possible_cpu(i) {
7238 struct softnet_data *sd = &per_cpu(softnet_data, i);
7239
7240 skb_queue_head_init(&sd->input_pkt_queue);
7241 skb_queue_head_init(&sd->process_queue);
7242 INIT_LIST_HEAD(&sd->poll_list);
7243 sd->output_queue_tailp = &sd->output_queue;
7244 #ifdef CONFIG_RPS
7245 sd->csd.func = rps_trigger_softirq;
7246 sd->csd.info = sd;
7247 sd->cpu = i;
7248 #endif
7249
7250 sd->backlog.poll = process_backlog;
7251 sd->backlog.weight = weight_p;
7252 }
7253
7254 dev_boot_phase = 0;
7255
7256 /* The loopback device is special if any other network devices
7257 * is present in a network namespace the loopback device must
7258 * be present. Since we now dynamically allocate and free the
7259 * loopback device ensure this invariant is maintained by
7260 * keeping the loopback device as the first device on the
7261 * list of network devices. Ensuring the loopback devices
7262 * is the first device that appears and the last network device
7263 * that disappears.
7264 */
7265 if (register_pernet_device(&loopback_net_ops))
7266 goto out;
7267
7268 if (register_pernet_device(&default_device_ops))
7269 goto out;
7270
7271 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7272 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7273
7274 hotcpu_notifier(dev_cpu_callback, 0);
7275 dst_init();
7276 rc = 0;
7277 out:
7278 return rc;
7279 }
7280
7281 subsys_initcall(net_dev_init);
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