2 * NET3 Protocol independent device support routines.
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.
9 * Derived from the non IP parts of dev.c 1.0.19
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
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>
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
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
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
51 * Rudi Cilibrasi : Pass the right thing to
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
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
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
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>
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>
99 #include <linux/rtnetlink.h>
100 #include <linux/stat.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>
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>
135 #include "net-sysfs.h"
137 /* Instead of increasing this, you should create a hash table. */
138 #define MAX_GRO_SKBS 8
140 /* This should be increased if a protocol with a bigger head is added. */
141 #define GRO_MAX_HEAD (MAX_HEADER + 128)
143 static DEFINE_SPINLOCK(ptype_lock);
144 static DEFINE_SPINLOCK(offload_lock);
145 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
146 struct list_head ptype_all __read_mostly; /* Taps */
147 static struct list_head offload_base __read_mostly;
150 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
153 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
155 * Writers must hold the rtnl semaphore while they loop through the
156 * dev_base_head list, and hold dev_base_lock for writing when they do the
157 * actual updates. This allows pure readers to access the list even
158 * while a writer is preparing to update it.
160 * To put it another way, dev_base_lock is held for writing only to
161 * protect against pure readers; the rtnl semaphore provides the
162 * protection against other writers.
164 * See, for example usages, register_netdevice() and
165 * unregister_netdevice(), which must be called with the rtnl
168 DEFINE_RWLOCK(dev_base_lock);
169 EXPORT_SYMBOL(dev_base_lock);
171 /* protects napi_hash addition/deletion and napi_gen_id */
172 static DEFINE_SPINLOCK(napi_hash_lock);
174 static unsigned int napi_gen_id;
175 static DEFINE_HASHTABLE(napi_hash, 8);
177 seqcount_t devnet_rename_seq;
179 static inline void dev_base_seq_inc(struct net *net)
181 while (++net->dev_base_seq == 0);
184 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
186 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
188 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
191 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
193 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
196 static inline void rps_lock(struct softnet_data *sd)
199 spin_lock(&sd->input_pkt_queue.lock);
203 static inline void rps_unlock(struct softnet_data *sd)
206 spin_unlock(&sd->input_pkt_queue.lock);
210 /* Device list insertion */
211 static void list_netdevice(struct net_device *dev)
213 struct net *net = dev_net(dev);
217 write_lock_bh(&dev_base_lock);
218 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
219 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
220 hlist_add_head_rcu(&dev->index_hlist,
221 dev_index_hash(net, dev->ifindex));
222 write_unlock_bh(&dev_base_lock);
224 dev_base_seq_inc(net);
227 /* Device list removal
228 * caller must respect a RCU grace period before freeing/reusing dev
230 static void unlist_netdevice(struct net_device *dev)
234 /* Unlink dev from the device chain */
235 write_lock_bh(&dev_base_lock);
236 list_del_rcu(&dev->dev_list);
237 hlist_del_rcu(&dev->name_hlist);
238 hlist_del_rcu(&dev->index_hlist);
239 write_unlock_bh(&dev_base_lock);
241 dev_base_seq_inc(dev_net(dev));
248 static RAW_NOTIFIER_HEAD(netdev_chain);
251 * Device drivers call our routines to queue packets here. We empty the
252 * queue in the local softnet handler.
255 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
256 EXPORT_PER_CPU_SYMBOL(softnet_data);
258 #ifdef CONFIG_LOCKDEP
260 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
261 * according to dev->type
263 static const unsigned short netdev_lock_type[] =
264 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
265 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
266 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
267 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
268 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
269 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
270 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
271 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
272 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
273 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
274 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
275 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
276 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
277 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
278 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
280 static const char *const netdev_lock_name[] =
281 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
282 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
283 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
284 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
285 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
286 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
287 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
288 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
289 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
290 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
291 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
292 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
293 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
294 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
295 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
297 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
298 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
300 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
304 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
305 if (netdev_lock_type[i] == dev_type)
307 /* the last key is used by default */
308 return ARRAY_SIZE(netdev_lock_type) - 1;
311 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
312 unsigned short dev_type)
316 i = netdev_lock_pos(dev_type);
317 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
318 netdev_lock_name[i]);
321 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
325 i = netdev_lock_pos(dev->type);
326 lockdep_set_class_and_name(&dev->addr_list_lock,
327 &netdev_addr_lock_key[i],
328 netdev_lock_name[i]);
331 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
332 unsigned short dev_type)
335 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
340 /*******************************************************************************
342 Protocol management and registration routines
344 *******************************************************************************/
347 * Add a protocol ID to the list. Now that the input handler is
348 * smarter we can dispense with all the messy stuff that used to be
351 * BEWARE!!! Protocol handlers, mangling input packets,
352 * MUST BE last in hash buckets and checking protocol handlers
353 * MUST start from promiscuous ptype_all chain in net_bh.
354 * It is true now, do not change it.
355 * Explanation follows: if protocol handler, mangling packet, will
356 * be the first on list, it is not able to sense, that packet
357 * is cloned and should be copied-on-write, so that it will
358 * change it and subsequent readers will get broken packet.
362 static inline struct list_head *ptype_head(const struct packet_type *pt)
364 if (pt->type == htons(ETH_P_ALL))
367 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
371 * dev_add_pack - add packet handler
372 * @pt: packet type declaration
374 * Add a protocol handler to the networking stack. The passed &packet_type
375 * is linked into kernel lists and may not be freed until it has been
376 * removed from the kernel lists.
378 * This call does not sleep therefore it can not
379 * guarantee all CPU's that are in middle of receiving packets
380 * will see the new packet type (until the next received packet).
383 void dev_add_pack(struct packet_type *pt)
385 struct list_head *head = ptype_head(pt);
387 spin_lock(&ptype_lock);
388 list_add_rcu(&pt->list, head);
389 spin_unlock(&ptype_lock);
391 EXPORT_SYMBOL(dev_add_pack);
394 * __dev_remove_pack - remove packet handler
395 * @pt: packet type declaration
397 * Remove a protocol handler that was previously added to the kernel
398 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
399 * from the kernel lists and can be freed or reused once this function
402 * The packet type might still be in use by receivers
403 * and must not be freed until after all the CPU's have gone
404 * through a quiescent state.
406 void __dev_remove_pack(struct packet_type *pt)
408 struct list_head *head = ptype_head(pt);
409 struct packet_type *pt1;
411 spin_lock(&ptype_lock);
413 list_for_each_entry(pt1, head, list) {
415 list_del_rcu(&pt->list);
420 pr_warn("dev_remove_pack: %p not found\n", pt);
422 spin_unlock(&ptype_lock);
424 EXPORT_SYMBOL(__dev_remove_pack);
427 * dev_remove_pack - remove packet handler
428 * @pt: packet type declaration
430 * Remove a protocol handler that was previously added to the kernel
431 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
432 * from the kernel lists and can be freed or reused once this function
435 * This call sleeps to guarantee that no CPU is looking at the packet
438 void dev_remove_pack(struct packet_type *pt)
440 __dev_remove_pack(pt);
444 EXPORT_SYMBOL(dev_remove_pack);
448 * dev_add_offload - register offload handlers
449 * @po: protocol offload declaration
451 * Add protocol offload handlers to the networking stack. The passed
452 * &proto_offload is linked into kernel lists and may not be freed until
453 * it has been removed from the kernel lists.
455 * This call does not sleep therefore it can not
456 * guarantee all CPU's that are in middle of receiving packets
457 * will see the new offload handlers (until the next received packet).
459 void dev_add_offload(struct packet_offload *po)
461 struct list_head *head = &offload_base;
463 spin_lock(&offload_lock);
464 list_add_rcu(&po->list, head);
465 spin_unlock(&offload_lock);
467 EXPORT_SYMBOL(dev_add_offload);
470 * __dev_remove_offload - remove offload handler
471 * @po: packet offload declaration
473 * Remove a protocol offload handler that was previously added to the
474 * kernel offload handlers by dev_add_offload(). The passed &offload_type
475 * is removed from the kernel lists and can be freed or reused once this
478 * The packet type might still be in use by receivers
479 * and must not be freed until after all the CPU's have gone
480 * through a quiescent state.
482 void __dev_remove_offload(struct packet_offload *po)
484 struct list_head *head = &offload_base;
485 struct packet_offload *po1;
487 spin_lock(&offload_lock);
489 list_for_each_entry(po1, head, list) {
491 list_del_rcu(&po->list);
496 pr_warn("dev_remove_offload: %p not found\n", po);
498 spin_unlock(&offload_lock);
500 EXPORT_SYMBOL(__dev_remove_offload);
503 * dev_remove_offload - remove packet offload handler
504 * @po: packet offload declaration
506 * Remove a packet offload handler that was previously added to the kernel
507 * offload handlers by dev_add_offload(). The passed &offload_type is
508 * removed from the kernel lists and can be freed or reused once this
511 * This call sleeps to guarantee that no CPU is looking at the packet
514 void dev_remove_offload(struct packet_offload *po)
516 __dev_remove_offload(po);
520 EXPORT_SYMBOL(dev_remove_offload);
522 /******************************************************************************
524 Device Boot-time Settings Routines
526 *******************************************************************************/
528 /* Boot time configuration table */
529 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
532 * netdev_boot_setup_add - add new setup entry
533 * @name: name of the device
534 * @map: configured settings for the device
536 * Adds new setup entry to the dev_boot_setup list. The function
537 * returns 0 on error and 1 on success. This is a generic routine to
540 static int netdev_boot_setup_add(char *name, struct ifmap *map)
542 struct netdev_boot_setup *s;
546 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
547 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
548 memset(s[i].name, 0, sizeof(s[i].name));
549 strlcpy(s[i].name, name, IFNAMSIZ);
550 memcpy(&s[i].map, map, sizeof(s[i].map));
555 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
559 * netdev_boot_setup_check - check boot time settings
560 * @dev: the netdevice
562 * Check boot time settings for the device.
563 * The found settings are set for the device to be used
564 * later in the device probing.
565 * Returns 0 if no settings found, 1 if they are.
567 int netdev_boot_setup_check(struct net_device *dev)
569 struct netdev_boot_setup *s = dev_boot_setup;
572 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
573 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
574 !strcmp(dev->name, s[i].name)) {
575 dev->irq = s[i].map.irq;
576 dev->base_addr = s[i].map.base_addr;
577 dev->mem_start = s[i].map.mem_start;
578 dev->mem_end = s[i].map.mem_end;
584 EXPORT_SYMBOL(netdev_boot_setup_check);
588 * netdev_boot_base - get address from boot time settings
589 * @prefix: prefix for network device
590 * @unit: id for network device
592 * Check boot time settings for the base address of device.
593 * The found settings are set for the device to be used
594 * later in the device probing.
595 * Returns 0 if no settings found.
597 unsigned long netdev_boot_base(const char *prefix, int unit)
599 const struct netdev_boot_setup *s = dev_boot_setup;
603 sprintf(name, "%s%d", prefix, unit);
606 * If device already registered then return base of 1
607 * to indicate not to probe for this interface
609 if (__dev_get_by_name(&init_net, name))
612 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
613 if (!strcmp(name, s[i].name))
614 return s[i].map.base_addr;
619 * Saves at boot time configured settings for any netdevice.
621 int __init netdev_boot_setup(char *str)
626 str = get_options(str, ARRAY_SIZE(ints), ints);
631 memset(&map, 0, sizeof(map));
635 map.base_addr = ints[2];
637 map.mem_start = ints[3];
639 map.mem_end = ints[4];
641 /* Add new entry to the list */
642 return netdev_boot_setup_add(str, &map);
645 __setup("netdev=", netdev_boot_setup);
647 /*******************************************************************************
649 Device Interface Subroutines
651 *******************************************************************************/
654 * __dev_get_by_name - find a device by its name
655 * @net: the applicable net namespace
656 * @name: name to find
658 * Find an interface by name. Must be called under RTNL semaphore
659 * or @dev_base_lock. If the name is found a pointer to the device
660 * is returned. If the name is not found then %NULL is returned. The
661 * reference counters are not incremented so the caller must be
662 * careful with locks.
665 struct net_device *__dev_get_by_name(struct net *net, const char *name)
667 struct net_device *dev;
668 struct hlist_head *head = dev_name_hash(net, name);
670 hlist_for_each_entry(dev, head, name_hlist)
671 if (!strncmp(dev->name, name, IFNAMSIZ))
676 EXPORT_SYMBOL(__dev_get_by_name);
679 * dev_get_by_name_rcu - find a device by its name
680 * @net: the applicable net namespace
681 * @name: name to find
683 * Find an interface by name.
684 * If the name is found a pointer to the device is returned.
685 * If the name is not found then %NULL is returned.
686 * The reference counters are not incremented so the caller must be
687 * careful with locks. The caller must hold RCU lock.
690 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
692 struct net_device *dev;
693 struct hlist_head *head = dev_name_hash(net, name);
695 hlist_for_each_entry_rcu(dev, head, name_hlist)
696 if (!strncmp(dev->name, name, IFNAMSIZ))
701 EXPORT_SYMBOL(dev_get_by_name_rcu);
704 * dev_get_by_name - find a device by its name
705 * @net: the applicable net namespace
706 * @name: name to find
708 * Find an interface by name. This can be called from any
709 * context and does its own locking. The returned handle has
710 * the usage count incremented and the caller must use dev_put() to
711 * release it when it is no longer needed. %NULL is returned if no
712 * matching device is found.
715 struct net_device *dev_get_by_name(struct net *net, const char *name)
717 struct net_device *dev;
720 dev = dev_get_by_name_rcu(net, name);
726 EXPORT_SYMBOL(dev_get_by_name);
729 * __dev_get_by_index - find a device by its ifindex
730 * @net: the applicable net namespace
731 * @ifindex: index of device
733 * Search for an interface by index. Returns %NULL if the device
734 * is not found or a pointer to the device. The device has not
735 * had its reference counter increased so the caller must be careful
736 * about locking. The caller must hold either the RTNL semaphore
740 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
742 struct net_device *dev;
743 struct hlist_head *head = dev_index_hash(net, ifindex);
745 hlist_for_each_entry(dev, head, index_hlist)
746 if (dev->ifindex == ifindex)
751 EXPORT_SYMBOL(__dev_get_by_index);
754 * dev_get_by_index_rcu - find a device by its ifindex
755 * @net: the applicable net namespace
756 * @ifindex: index of device
758 * Search for an interface by index. Returns %NULL if the device
759 * is not found or a pointer to the device. The device has not
760 * had its reference counter increased so the caller must be careful
761 * about locking. The caller must hold RCU lock.
764 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
766 struct net_device *dev;
767 struct hlist_head *head = dev_index_hash(net, ifindex);
769 hlist_for_each_entry_rcu(dev, head, index_hlist)
770 if (dev->ifindex == ifindex)
775 EXPORT_SYMBOL(dev_get_by_index_rcu);
779 * dev_get_by_index - find a device by its ifindex
780 * @net: the applicable net namespace
781 * @ifindex: index of device
783 * Search for an interface by index. Returns NULL if the device
784 * is not found or a pointer to the device. The device returned has
785 * had a reference added and the pointer is safe until the user calls
786 * dev_put to indicate they have finished with it.
789 struct net_device *dev_get_by_index(struct net *net, int ifindex)
791 struct net_device *dev;
794 dev = dev_get_by_index_rcu(net, ifindex);
800 EXPORT_SYMBOL(dev_get_by_index);
803 * netdev_get_name - get a netdevice name, knowing its ifindex.
804 * @net: network namespace
805 * @name: a pointer to the buffer where the name will be stored.
806 * @ifindex: the ifindex of the interface to get the name from.
808 * The use of raw_seqcount_begin() and cond_resched() before
809 * retrying is required as we want to give the writers a chance
810 * to complete when CONFIG_PREEMPT is not set.
812 int netdev_get_name(struct net *net, char *name, int ifindex)
814 struct net_device *dev;
818 seq = raw_seqcount_begin(&devnet_rename_seq);
820 dev = dev_get_by_index_rcu(net, ifindex);
826 strcpy(name, dev->name);
828 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
837 * dev_getbyhwaddr_rcu - find a device by its hardware address
838 * @net: the applicable net namespace
839 * @type: media type of device
840 * @ha: hardware address
842 * Search for an interface by MAC address. Returns NULL if the device
843 * is not found or a pointer to the device.
844 * The caller must hold RCU or RTNL.
845 * The returned device has not had its ref count increased
846 * and the caller must therefore be careful about locking
850 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
853 struct net_device *dev;
855 for_each_netdev_rcu(net, dev)
856 if (dev->type == type &&
857 !memcmp(dev->dev_addr, ha, dev->addr_len))
862 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
864 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
866 struct net_device *dev;
869 for_each_netdev(net, dev)
870 if (dev->type == type)
875 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
877 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
879 struct net_device *dev, *ret = NULL;
882 for_each_netdev_rcu(net, dev)
883 if (dev->type == type) {
891 EXPORT_SYMBOL(dev_getfirstbyhwtype);
894 * dev_get_by_flags_rcu - find any device with given flags
895 * @net: the applicable net namespace
896 * @if_flags: IFF_* values
897 * @mask: bitmask of bits in if_flags to check
899 * Search for any interface with the given flags. Returns NULL if a device
900 * is not found or a pointer to the device. Must be called inside
901 * rcu_read_lock(), and result refcount is unchanged.
904 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
907 struct net_device *dev, *ret;
910 for_each_netdev_rcu(net, dev) {
911 if (((dev->flags ^ if_flags) & mask) == 0) {
918 EXPORT_SYMBOL(dev_get_by_flags_rcu);
921 * dev_valid_name - check if name is okay for network device
924 * Network device names need to be valid file names to
925 * to allow sysfs to work. We also disallow any kind of
928 bool dev_valid_name(const char *name)
932 if (strlen(name) >= IFNAMSIZ)
934 if (!strcmp(name, ".") || !strcmp(name, ".."))
938 if (*name == '/' || isspace(*name))
944 EXPORT_SYMBOL(dev_valid_name);
947 * __dev_alloc_name - allocate a name for a device
948 * @net: network namespace to allocate the device name in
949 * @name: name format string
950 * @buf: scratch buffer and result name string
952 * Passed a format string - eg "lt%d" it will try and find a suitable
953 * id. It scans list of devices to build up a free map, then chooses
954 * the first empty slot. The caller must hold the dev_base or rtnl lock
955 * while allocating the name and adding the device in order to avoid
957 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
958 * Returns the number of the unit assigned or a negative errno code.
961 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
965 const int max_netdevices = 8*PAGE_SIZE;
966 unsigned long *inuse;
967 struct net_device *d;
969 p = strnchr(name, IFNAMSIZ-1, '%');
972 * Verify the string as this thing may have come from
973 * the user. There must be either one "%d" and no other "%"
976 if (p[1] != 'd' || strchr(p + 2, '%'))
979 /* Use one page as a bit array of possible slots */
980 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
984 for_each_netdev(net, d) {
985 if (!sscanf(d->name, name, &i))
987 if (i < 0 || i >= max_netdevices)
990 /* avoid cases where sscanf is not exact inverse of printf */
991 snprintf(buf, IFNAMSIZ, name, i);
992 if (!strncmp(buf, d->name, IFNAMSIZ))
996 i = find_first_zero_bit(inuse, max_netdevices);
997 free_page((unsigned long) inuse);
1001 snprintf(buf, IFNAMSIZ, name, i);
1002 if (!__dev_get_by_name(net, buf))
1005 /* It is possible to run out of possible slots
1006 * when the name is long and there isn't enough space left
1007 * for the digits, or if all bits are used.
1013 * dev_alloc_name - allocate a name for a device
1015 * @name: name format string
1017 * Passed a format string - eg "lt%d" it will try and find a suitable
1018 * id. It scans list of devices to build up a free map, then chooses
1019 * the first empty slot. The caller must hold the dev_base or rtnl lock
1020 * while allocating the name and adding the device in order to avoid
1022 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1023 * Returns the number of the unit assigned or a negative errno code.
1026 int dev_alloc_name(struct net_device *dev, const char *name)
1032 BUG_ON(!dev_net(dev));
1034 ret = __dev_alloc_name(net, name, buf);
1036 strlcpy(dev->name, buf, IFNAMSIZ);
1039 EXPORT_SYMBOL(dev_alloc_name);
1041 static int dev_alloc_name_ns(struct net *net,
1042 struct net_device *dev,
1048 ret = __dev_alloc_name(net, name, buf);
1050 strlcpy(dev->name, buf, IFNAMSIZ);
1054 static int dev_get_valid_name(struct net *net,
1055 struct net_device *dev,
1060 if (!dev_valid_name(name))
1063 if (strchr(name, '%'))
1064 return dev_alloc_name_ns(net, dev, name);
1065 else if (__dev_get_by_name(net, name))
1067 else if (dev->name != name)
1068 strlcpy(dev->name, name, IFNAMSIZ);
1074 * dev_change_name - change name of a device
1076 * @newname: name (or format string) must be at least IFNAMSIZ
1078 * Change name of a device, can pass format strings "eth%d".
1081 int dev_change_name(struct net_device *dev, const char *newname)
1083 char oldname[IFNAMSIZ];
1089 BUG_ON(!dev_net(dev));
1092 if (dev->flags & IFF_UP)
1095 write_seqcount_begin(&devnet_rename_seq);
1097 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1098 write_seqcount_end(&devnet_rename_seq);
1102 memcpy(oldname, dev->name, IFNAMSIZ);
1104 err = dev_get_valid_name(net, dev, newname);
1106 write_seqcount_end(&devnet_rename_seq);
1111 ret = device_rename(&dev->dev, dev->name);
1113 memcpy(dev->name, oldname, IFNAMSIZ);
1114 write_seqcount_end(&devnet_rename_seq);
1118 write_seqcount_end(&devnet_rename_seq);
1120 write_lock_bh(&dev_base_lock);
1121 hlist_del_rcu(&dev->name_hlist);
1122 write_unlock_bh(&dev_base_lock);
1126 write_lock_bh(&dev_base_lock);
1127 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1128 write_unlock_bh(&dev_base_lock);
1130 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1131 ret = notifier_to_errno(ret);
1134 /* err >= 0 after dev_alloc_name() or stores the first errno */
1137 write_seqcount_begin(&devnet_rename_seq);
1138 memcpy(dev->name, oldname, IFNAMSIZ);
1141 pr_err("%s: name change rollback failed: %d\n",
1150 * dev_set_alias - change ifalias of a device
1152 * @alias: name up to IFALIASZ
1153 * @len: limit of bytes to copy from info
1155 * Set ifalias for a device,
1157 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1163 if (len >= IFALIASZ)
1167 kfree(dev->ifalias);
1168 dev->ifalias = NULL;
1172 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1175 dev->ifalias = new_ifalias;
1177 strlcpy(dev->ifalias, alias, len+1);
1183 * netdev_features_change - device changes features
1184 * @dev: device to cause notification
1186 * Called to indicate a device has changed features.
1188 void netdev_features_change(struct net_device *dev)
1190 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1192 EXPORT_SYMBOL(netdev_features_change);
1195 * netdev_state_change - device changes state
1196 * @dev: device to cause notification
1198 * Called to indicate a device has changed state. This function calls
1199 * the notifier chains for netdev_chain and sends a NEWLINK message
1200 * to the routing socket.
1202 void netdev_state_change(struct net_device *dev)
1204 if (dev->flags & IFF_UP) {
1205 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1206 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
1209 EXPORT_SYMBOL(netdev_state_change);
1212 * netdev_notify_peers - notify network peers about existence of @dev
1213 * @dev: network device
1215 * Generate traffic such that interested network peers are aware of
1216 * @dev, such as by generating a gratuitous ARP. This may be used when
1217 * a device wants to inform the rest of the network about some sort of
1218 * reconfiguration such as a failover event or virtual machine
1221 void netdev_notify_peers(struct net_device *dev)
1224 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1227 EXPORT_SYMBOL(netdev_notify_peers);
1229 static int __dev_open(struct net_device *dev)
1231 const struct net_device_ops *ops = dev->netdev_ops;
1236 if (!netif_device_present(dev))
1239 /* Block netpoll from trying to do any rx path servicing.
1240 * If we don't do this there is a chance ndo_poll_controller
1241 * or ndo_poll may be running while we open the device
1243 netpoll_rx_disable(dev);
1245 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1246 ret = notifier_to_errno(ret);
1250 set_bit(__LINK_STATE_START, &dev->state);
1252 if (ops->ndo_validate_addr)
1253 ret = ops->ndo_validate_addr(dev);
1255 if (!ret && ops->ndo_open)
1256 ret = ops->ndo_open(dev);
1258 netpoll_rx_enable(dev);
1261 clear_bit(__LINK_STATE_START, &dev->state);
1263 dev->flags |= IFF_UP;
1264 net_dmaengine_get();
1265 dev_set_rx_mode(dev);
1267 add_device_randomness(dev->dev_addr, dev->addr_len);
1274 * dev_open - prepare an interface for use.
1275 * @dev: device to open
1277 * Takes a device from down to up state. The device's private open
1278 * function is invoked and then the multicast lists are loaded. Finally
1279 * the device is moved into the up state and a %NETDEV_UP message is
1280 * sent to the netdev notifier chain.
1282 * Calling this function on an active interface is a nop. On a failure
1283 * a negative errno code is returned.
1285 int dev_open(struct net_device *dev)
1289 if (dev->flags & IFF_UP)
1292 ret = __dev_open(dev);
1296 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1297 call_netdevice_notifiers(NETDEV_UP, dev);
1301 EXPORT_SYMBOL(dev_open);
1303 static int __dev_close_many(struct list_head *head)
1305 struct net_device *dev;
1310 list_for_each_entry(dev, head, unreg_list) {
1311 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1313 clear_bit(__LINK_STATE_START, &dev->state);
1315 /* Synchronize to scheduled poll. We cannot touch poll list, it
1316 * can be even on different cpu. So just clear netif_running().
1318 * dev->stop() will invoke napi_disable() on all of it's
1319 * napi_struct instances on this device.
1321 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1324 dev_deactivate_many(head);
1326 list_for_each_entry(dev, head, unreg_list) {
1327 const struct net_device_ops *ops = dev->netdev_ops;
1330 * Call the device specific close. This cannot fail.
1331 * Only if device is UP
1333 * We allow it to be called even after a DETACH hot-plug
1339 dev->flags &= ~IFF_UP;
1340 net_dmaengine_put();
1346 static int __dev_close(struct net_device *dev)
1351 /* Temporarily disable netpoll until the interface is down */
1352 netpoll_rx_disable(dev);
1354 list_add(&dev->unreg_list, &single);
1355 retval = __dev_close_many(&single);
1358 netpoll_rx_enable(dev);
1362 static int dev_close_many(struct list_head *head)
1364 struct net_device *dev, *tmp;
1365 LIST_HEAD(tmp_list);
1367 list_for_each_entry_safe(dev, tmp, head, unreg_list)
1368 if (!(dev->flags & IFF_UP))
1369 list_move(&dev->unreg_list, &tmp_list);
1371 __dev_close_many(head);
1373 list_for_each_entry(dev, head, unreg_list) {
1374 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1375 call_netdevice_notifiers(NETDEV_DOWN, dev);
1378 /* rollback_registered_many needs the complete original list */
1379 list_splice(&tmp_list, head);
1384 * dev_close - shutdown an interface.
1385 * @dev: device to shutdown
1387 * This function moves an active device into down state. A
1388 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1389 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1392 int dev_close(struct net_device *dev)
1394 if (dev->flags & IFF_UP) {
1397 /* Block netpoll rx while the interface is going down */
1398 netpoll_rx_disable(dev);
1400 list_add(&dev->unreg_list, &single);
1401 dev_close_many(&single);
1404 netpoll_rx_enable(dev);
1408 EXPORT_SYMBOL(dev_close);
1412 * dev_disable_lro - disable Large Receive Offload on a device
1415 * Disable Large Receive Offload (LRO) on a net device. Must be
1416 * called under RTNL. This is needed if received packets may be
1417 * forwarded to another interface.
1419 void dev_disable_lro(struct net_device *dev)
1422 * If we're trying to disable lro on a vlan device
1423 * use the underlying physical device instead
1425 if (is_vlan_dev(dev))
1426 dev = vlan_dev_real_dev(dev);
1428 dev->wanted_features &= ~NETIF_F_LRO;
1429 netdev_update_features(dev);
1431 if (unlikely(dev->features & NETIF_F_LRO))
1432 netdev_WARN(dev, "failed to disable LRO!\n");
1434 EXPORT_SYMBOL(dev_disable_lro);
1436 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1437 struct net_device *dev)
1439 struct netdev_notifier_info info;
1441 netdev_notifier_info_init(&info, dev);
1442 return nb->notifier_call(nb, val, &info);
1445 static int dev_boot_phase = 1;
1448 * register_netdevice_notifier - register a network notifier block
1451 * Register a notifier to be called when network device events occur.
1452 * The notifier passed is linked into the kernel structures and must
1453 * not be reused until it has been unregistered. A negative errno code
1454 * is returned on a failure.
1456 * When registered all registration and up events are replayed
1457 * to the new notifier to allow device to have a race free
1458 * view of the network device list.
1461 int register_netdevice_notifier(struct notifier_block *nb)
1463 struct net_device *dev;
1464 struct net_device *last;
1469 err = raw_notifier_chain_register(&netdev_chain, nb);
1475 for_each_netdev(net, dev) {
1476 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1477 err = notifier_to_errno(err);
1481 if (!(dev->flags & IFF_UP))
1484 call_netdevice_notifier(nb, NETDEV_UP, dev);
1495 for_each_netdev(net, dev) {
1499 if (dev->flags & IFF_UP) {
1500 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1502 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1504 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1509 raw_notifier_chain_unregister(&netdev_chain, nb);
1512 EXPORT_SYMBOL(register_netdevice_notifier);
1515 * unregister_netdevice_notifier - unregister a network notifier block
1518 * Unregister a notifier previously registered by
1519 * register_netdevice_notifier(). The notifier is unlinked into the
1520 * kernel structures and may then be reused. A negative errno code
1521 * is returned on a failure.
1523 * After unregistering unregister and down device events are synthesized
1524 * for all devices on the device list to the removed notifier to remove
1525 * the need for special case cleanup code.
1528 int unregister_netdevice_notifier(struct notifier_block *nb)
1530 struct net_device *dev;
1535 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1540 for_each_netdev(net, dev) {
1541 if (dev->flags & IFF_UP) {
1542 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1544 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1546 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1553 EXPORT_SYMBOL(unregister_netdevice_notifier);
1556 * call_netdevice_notifiers_info - call all network notifier blocks
1557 * @val: value passed unmodified to notifier function
1558 * @dev: net_device pointer passed unmodified to notifier function
1559 * @info: notifier information data
1561 * Call all network notifier blocks. Parameters and return value
1562 * are as for raw_notifier_call_chain().
1565 int call_netdevice_notifiers_info(unsigned long val, struct net_device *dev,
1566 struct netdev_notifier_info *info)
1569 netdev_notifier_info_init(info, dev);
1570 return raw_notifier_call_chain(&netdev_chain, val, info);
1572 EXPORT_SYMBOL(call_netdevice_notifiers_info);
1575 * call_netdevice_notifiers - call all network notifier blocks
1576 * @val: value passed unmodified to notifier function
1577 * @dev: net_device pointer passed unmodified to notifier function
1579 * Call all network notifier blocks. Parameters and return value
1580 * are as for raw_notifier_call_chain().
1583 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1585 struct netdev_notifier_info info;
1587 return call_netdevice_notifiers_info(val, dev, &info);
1589 EXPORT_SYMBOL(call_netdevice_notifiers);
1591 static struct static_key netstamp_needed __read_mostly;
1592 #ifdef HAVE_JUMP_LABEL
1593 /* We are not allowed to call static_key_slow_dec() from irq context
1594 * If net_disable_timestamp() is called from irq context, defer the
1595 * static_key_slow_dec() calls.
1597 static atomic_t netstamp_needed_deferred;
1600 void net_enable_timestamp(void)
1602 #ifdef HAVE_JUMP_LABEL
1603 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1607 static_key_slow_dec(&netstamp_needed);
1611 static_key_slow_inc(&netstamp_needed);
1613 EXPORT_SYMBOL(net_enable_timestamp);
1615 void net_disable_timestamp(void)
1617 #ifdef HAVE_JUMP_LABEL
1618 if (in_interrupt()) {
1619 atomic_inc(&netstamp_needed_deferred);
1623 static_key_slow_dec(&netstamp_needed);
1625 EXPORT_SYMBOL(net_disable_timestamp);
1627 static inline void net_timestamp_set(struct sk_buff *skb)
1629 skb->tstamp.tv64 = 0;
1630 if (static_key_false(&netstamp_needed))
1631 __net_timestamp(skb);
1634 #define net_timestamp_check(COND, SKB) \
1635 if (static_key_false(&netstamp_needed)) { \
1636 if ((COND) && !(SKB)->tstamp.tv64) \
1637 __net_timestamp(SKB); \
1640 static inline bool is_skb_forwardable(struct net_device *dev,
1641 struct sk_buff *skb)
1645 if (!(dev->flags & IFF_UP))
1648 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1649 if (skb->len <= len)
1652 /* if TSO is enabled, we don't care about the length as the packet
1653 * could be forwarded without being segmented before
1655 if (skb_is_gso(skb))
1662 * dev_forward_skb - loopback an skb to another netif
1664 * @dev: destination network device
1665 * @skb: buffer to forward
1668 * NET_RX_SUCCESS (no congestion)
1669 * NET_RX_DROP (packet was dropped, but freed)
1671 * dev_forward_skb can be used for injecting an skb from the
1672 * start_xmit function of one device into the receive queue
1673 * of another device.
1675 * The receiving device may be in another namespace, so
1676 * we have to clear all information in the skb that could
1677 * impact namespace isolation.
1679 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1681 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1682 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1683 atomic_long_inc(&dev->rx_dropped);
1689 if (unlikely(!is_skb_forwardable(dev, skb))) {
1690 atomic_long_inc(&dev->rx_dropped);
1694 skb_scrub_packet(skb);
1695 skb->protocol = eth_type_trans(skb, dev);
1697 /* eth_type_trans() can set pkt_type.
1698 * clear pkt_type _after_ calling eth_type_trans()
1700 skb->pkt_type = PACKET_HOST;
1702 return netif_rx(skb);
1704 EXPORT_SYMBOL_GPL(dev_forward_skb);
1706 static inline int deliver_skb(struct sk_buff *skb,
1707 struct packet_type *pt_prev,
1708 struct net_device *orig_dev)
1710 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1712 atomic_inc(&skb->users);
1713 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1716 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1718 if (!ptype->af_packet_priv || !skb->sk)
1721 if (ptype->id_match)
1722 return ptype->id_match(ptype, skb->sk);
1723 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1730 * Support routine. Sends outgoing frames to any network
1731 * taps currently in use.
1734 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1736 struct packet_type *ptype;
1737 struct sk_buff *skb2 = NULL;
1738 struct packet_type *pt_prev = NULL;
1741 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1742 /* Never send packets back to the socket
1743 * they originated from - MvS (miquels@drinkel.ow.org)
1745 if ((ptype->dev == dev || !ptype->dev) &&
1746 (!skb_loop_sk(ptype, skb))) {
1748 deliver_skb(skb2, pt_prev, skb->dev);
1753 skb2 = skb_clone(skb, GFP_ATOMIC);
1757 net_timestamp_set(skb2);
1759 /* skb->nh should be correctly
1760 set by sender, so that the second statement is
1761 just protection against buggy protocols.
1763 skb_reset_mac_header(skb2);
1765 if (skb_network_header(skb2) < skb2->data ||
1766 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1767 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1768 ntohs(skb2->protocol),
1770 skb_reset_network_header(skb2);
1773 skb2->transport_header = skb2->network_header;
1774 skb2->pkt_type = PACKET_OUTGOING;
1779 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1784 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1785 * @dev: Network device
1786 * @txq: number of queues available
1788 * If real_num_tx_queues is changed the tc mappings may no longer be
1789 * valid. To resolve this verify the tc mapping remains valid and if
1790 * not NULL the mapping. With no priorities mapping to this
1791 * offset/count pair it will no longer be used. In the worst case TC0
1792 * is invalid nothing can be done so disable priority mappings. If is
1793 * expected that drivers will fix this mapping if they can before
1794 * calling netif_set_real_num_tx_queues.
1796 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1799 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1801 /* If TC0 is invalidated disable TC mapping */
1802 if (tc->offset + tc->count > txq) {
1803 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1808 /* Invalidated prio to tc mappings set to TC0 */
1809 for (i = 1; i < TC_BITMASK + 1; i++) {
1810 int q = netdev_get_prio_tc_map(dev, i);
1812 tc = &dev->tc_to_txq[q];
1813 if (tc->offset + tc->count > txq) {
1814 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1816 netdev_set_prio_tc_map(dev, i, 0);
1822 static DEFINE_MUTEX(xps_map_mutex);
1823 #define xmap_dereference(P) \
1824 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1826 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1829 struct xps_map *map = NULL;
1833 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1835 for (pos = 0; map && pos < map->len; pos++) {
1836 if (map->queues[pos] == index) {
1838 map->queues[pos] = map->queues[--map->len];
1840 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1841 kfree_rcu(map, rcu);
1851 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1853 struct xps_dev_maps *dev_maps;
1855 bool active = false;
1857 mutex_lock(&xps_map_mutex);
1858 dev_maps = xmap_dereference(dev->xps_maps);
1863 for_each_possible_cpu(cpu) {
1864 for (i = index; i < dev->num_tx_queues; i++) {
1865 if (!remove_xps_queue(dev_maps, cpu, i))
1868 if (i == dev->num_tx_queues)
1873 RCU_INIT_POINTER(dev->xps_maps, NULL);
1874 kfree_rcu(dev_maps, rcu);
1877 for (i = index; i < dev->num_tx_queues; i++)
1878 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1882 mutex_unlock(&xps_map_mutex);
1885 static struct xps_map *expand_xps_map(struct xps_map *map,
1888 struct xps_map *new_map;
1889 int alloc_len = XPS_MIN_MAP_ALLOC;
1892 for (pos = 0; map && pos < map->len; pos++) {
1893 if (map->queues[pos] != index)
1898 /* Need to add queue to this CPU's existing map */
1900 if (pos < map->alloc_len)
1903 alloc_len = map->alloc_len * 2;
1906 /* Need to allocate new map to store queue on this CPU's map */
1907 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1912 for (i = 0; i < pos; i++)
1913 new_map->queues[i] = map->queues[i];
1914 new_map->alloc_len = alloc_len;
1920 int netif_set_xps_queue(struct net_device *dev, struct cpumask *mask, u16 index)
1922 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1923 struct xps_map *map, *new_map;
1924 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1925 int cpu, numa_node_id = -2;
1926 bool active = false;
1928 mutex_lock(&xps_map_mutex);
1930 dev_maps = xmap_dereference(dev->xps_maps);
1932 /* allocate memory for queue storage */
1933 for_each_online_cpu(cpu) {
1934 if (!cpumask_test_cpu(cpu, mask))
1938 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1939 if (!new_dev_maps) {
1940 mutex_unlock(&xps_map_mutex);
1944 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1947 map = expand_xps_map(map, cpu, index);
1951 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1955 goto out_no_new_maps;
1957 for_each_possible_cpu(cpu) {
1958 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1959 /* add queue to CPU maps */
1962 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1963 while ((pos < map->len) && (map->queues[pos] != index))
1966 if (pos == map->len)
1967 map->queues[map->len++] = index;
1969 if (numa_node_id == -2)
1970 numa_node_id = cpu_to_node(cpu);
1971 else if (numa_node_id != cpu_to_node(cpu))
1974 } else if (dev_maps) {
1975 /* fill in the new device map from the old device map */
1976 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1977 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1982 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1984 /* Cleanup old maps */
1986 for_each_possible_cpu(cpu) {
1987 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1988 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1989 if (map && map != new_map)
1990 kfree_rcu(map, rcu);
1993 kfree_rcu(dev_maps, rcu);
1996 dev_maps = new_dev_maps;
2000 /* update Tx queue numa node */
2001 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2002 (numa_node_id >= 0) ? numa_node_id :
2008 /* removes queue from unused CPUs */
2009 for_each_possible_cpu(cpu) {
2010 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2013 if (remove_xps_queue(dev_maps, cpu, index))
2017 /* free map if not active */
2019 RCU_INIT_POINTER(dev->xps_maps, NULL);
2020 kfree_rcu(dev_maps, rcu);
2024 mutex_unlock(&xps_map_mutex);
2028 /* remove any maps that we added */
2029 for_each_possible_cpu(cpu) {
2030 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2031 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2033 if (new_map && new_map != map)
2037 mutex_unlock(&xps_map_mutex);
2039 kfree(new_dev_maps);
2042 EXPORT_SYMBOL(netif_set_xps_queue);
2046 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2047 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2049 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2053 if (txq < 1 || txq > dev->num_tx_queues)
2056 if (dev->reg_state == NETREG_REGISTERED ||
2057 dev->reg_state == NETREG_UNREGISTERING) {
2060 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2066 netif_setup_tc(dev, txq);
2068 if (txq < dev->real_num_tx_queues) {
2069 qdisc_reset_all_tx_gt(dev, txq);
2071 netif_reset_xps_queues_gt(dev, txq);
2076 dev->real_num_tx_queues = txq;
2079 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2083 * netif_set_real_num_rx_queues - set actual number of RX queues used
2084 * @dev: Network device
2085 * @rxq: Actual number of RX queues
2087 * This must be called either with the rtnl_lock held or before
2088 * registration of the net device. Returns 0 on success, or a
2089 * negative error code. If called before registration, it always
2092 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2096 if (rxq < 1 || rxq > dev->num_rx_queues)
2099 if (dev->reg_state == NETREG_REGISTERED) {
2102 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2108 dev->real_num_rx_queues = rxq;
2111 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2115 * netif_get_num_default_rss_queues - default number of RSS queues
2117 * This routine should set an upper limit on the number of RSS queues
2118 * used by default by multiqueue devices.
2120 int netif_get_num_default_rss_queues(void)
2122 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2124 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2126 static inline void __netif_reschedule(struct Qdisc *q)
2128 struct softnet_data *sd;
2129 unsigned long flags;
2131 local_irq_save(flags);
2132 sd = &__get_cpu_var(softnet_data);
2133 q->next_sched = NULL;
2134 *sd->output_queue_tailp = q;
2135 sd->output_queue_tailp = &q->next_sched;
2136 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2137 local_irq_restore(flags);
2140 void __netif_schedule(struct Qdisc *q)
2142 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2143 __netif_reschedule(q);
2145 EXPORT_SYMBOL(__netif_schedule);
2147 void dev_kfree_skb_irq(struct sk_buff *skb)
2149 if (atomic_dec_and_test(&skb->users)) {
2150 struct softnet_data *sd;
2151 unsigned long flags;
2153 local_irq_save(flags);
2154 sd = &__get_cpu_var(softnet_data);
2155 skb->next = sd->completion_queue;
2156 sd->completion_queue = skb;
2157 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2158 local_irq_restore(flags);
2161 EXPORT_SYMBOL(dev_kfree_skb_irq);
2163 void dev_kfree_skb_any(struct sk_buff *skb)
2165 if (in_irq() || irqs_disabled())
2166 dev_kfree_skb_irq(skb);
2170 EXPORT_SYMBOL(dev_kfree_skb_any);
2174 * netif_device_detach - mark device as removed
2175 * @dev: network device
2177 * Mark device as removed from system and therefore no longer available.
2179 void netif_device_detach(struct net_device *dev)
2181 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2182 netif_running(dev)) {
2183 netif_tx_stop_all_queues(dev);
2186 EXPORT_SYMBOL(netif_device_detach);
2189 * netif_device_attach - mark device as attached
2190 * @dev: network device
2192 * Mark device as attached from system and restart if needed.
2194 void netif_device_attach(struct net_device *dev)
2196 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2197 netif_running(dev)) {
2198 netif_tx_wake_all_queues(dev);
2199 __netdev_watchdog_up(dev);
2202 EXPORT_SYMBOL(netif_device_attach);
2204 static void skb_warn_bad_offload(const struct sk_buff *skb)
2206 static const netdev_features_t null_features = 0;
2207 struct net_device *dev = skb->dev;
2208 const char *driver = "";
2210 if (!net_ratelimit())
2213 if (dev && dev->dev.parent)
2214 driver = dev_driver_string(dev->dev.parent);
2216 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2217 "gso_type=%d ip_summed=%d\n",
2218 driver, dev ? &dev->features : &null_features,
2219 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2220 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2221 skb_shinfo(skb)->gso_type, skb->ip_summed);
2225 * Invalidate hardware checksum when packet is to be mangled, and
2226 * complete checksum manually on outgoing path.
2228 int skb_checksum_help(struct sk_buff *skb)
2231 int ret = 0, offset;
2233 if (skb->ip_summed == CHECKSUM_COMPLETE)
2234 goto out_set_summed;
2236 if (unlikely(skb_shinfo(skb)->gso_size)) {
2237 skb_warn_bad_offload(skb);
2241 /* Before computing a checksum, we should make sure no frag could
2242 * be modified by an external entity : checksum could be wrong.
2244 if (skb_has_shared_frag(skb)) {
2245 ret = __skb_linearize(skb);
2250 offset = skb_checksum_start_offset(skb);
2251 BUG_ON(offset >= skb_headlen(skb));
2252 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2254 offset += skb->csum_offset;
2255 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2257 if (skb_cloned(skb) &&
2258 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2259 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2264 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2266 skb->ip_summed = CHECKSUM_NONE;
2270 EXPORT_SYMBOL(skb_checksum_help);
2272 __be16 skb_network_protocol(struct sk_buff *skb)
2274 __be16 type = skb->protocol;
2275 int vlan_depth = ETH_HLEN;
2277 /* Tunnel gso handlers can set protocol to ethernet. */
2278 if (type == htons(ETH_P_TEB)) {
2281 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2284 eth = (struct ethhdr *)skb_mac_header(skb);
2285 type = eth->h_proto;
2288 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2289 struct vlan_hdr *vh;
2291 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2294 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2295 type = vh->h_vlan_encapsulated_proto;
2296 vlan_depth += VLAN_HLEN;
2303 * skb_mac_gso_segment - mac layer segmentation handler.
2304 * @skb: buffer to segment
2305 * @features: features for the output path (see dev->features)
2307 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2308 netdev_features_t features)
2310 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2311 struct packet_offload *ptype;
2312 __be16 type = skb_network_protocol(skb);
2314 if (unlikely(!type))
2315 return ERR_PTR(-EINVAL);
2317 __skb_pull(skb, skb->mac_len);
2320 list_for_each_entry_rcu(ptype, &offload_base, list) {
2321 if (ptype->type == type && ptype->callbacks.gso_segment) {
2322 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2325 err = ptype->callbacks.gso_send_check(skb);
2326 segs = ERR_PTR(err);
2327 if (err || skb_gso_ok(skb, features))
2329 __skb_push(skb, (skb->data -
2330 skb_network_header(skb)));
2332 segs = ptype->callbacks.gso_segment(skb, features);
2338 __skb_push(skb, skb->data - skb_mac_header(skb));
2342 EXPORT_SYMBOL(skb_mac_gso_segment);
2345 /* openvswitch calls this on rx path, so we need a different check.
2347 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2350 return skb->ip_summed != CHECKSUM_PARTIAL;
2352 return skb->ip_summed == CHECKSUM_NONE;
2356 * __skb_gso_segment - Perform segmentation on skb.
2357 * @skb: buffer to segment
2358 * @features: features for the output path (see dev->features)
2359 * @tx_path: whether it is called in TX path
2361 * This function segments the given skb and returns a list of segments.
2363 * It may return NULL if the skb requires no segmentation. This is
2364 * only possible when GSO is used for verifying header integrity.
2366 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2367 netdev_features_t features, bool tx_path)
2369 if (unlikely(skb_needs_check(skb, tx_path))) {
2372 skb_warn_bad_offload(skb);
2374 if (skb_header_cloned(skb) &&
2375 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2376 return ERR_PTR(err);
2379 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2380 skb_reset_mac_header(skb);
2381 skb_reset_mac_len(skb);
2383 return skb_mac_gso_segment(skb, features);
2385 EXPORT_SYMBOL(__skb_gso_segment);
2387 /* Take action when hardware reception checksum errors are detected. */
2389 void netdev_rx_csum_fault(struct net_device *dev)
2391 if (net_ratelimit()) {
2392 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2396 EXPORT_SYMBOL(netdev_rx_csum_fault);
2399 /* Actually, we should eliminate this check as soon as we know, that:
2400 * 1. IOMMU is present and allows to map all the memory.
2401 * 2. No high memory really exists on this machine.
2404 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2406 #ifdef CONFIG_HIGHMEM
2408 if (!(dev->features & NETIF_F_HIGHDMA)) {
2409 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2410 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2411 if (PageHighMem(skb_frag_page(frag)))
2416 if (PCI_DMA_BUS_IS_PHYS) {
2417 struct device *pdev = dev->dev.parent;
2421 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2422 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2423 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2424 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2433 void (*destructor)(struct sk_buff *skb);
2436 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2438 static void dev_gso_skb_destructor(struct sk_buff *skb)
2440 struct dev_gso_cb *cb;
2443 struct sk_buff *nskb = skb->next;
2445 skb->next = nskb->next;
2448 } while (skb->next);
2450 cb = DEV_GSO_CB(skb);
2452 cb->destructor(skb);
2456 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2457 * @skb: buffer to segment
2458 * @features: device features as applicable to this skb
2460 * This function segments the given skb and stores the list of segments
2463 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2465 struct sk_buff *segs;
2467 segs = skb_gso_segment(skb, features);
2469 /* Verifying header integrity only. */
2474 return PTR_ERR(segs);
2477 DEV_GSO_CB(skb)->destructor = skb->destructor;
2478 skb->destructor = dev_gso_skb_destructor;
2483 static netdev_features_t harmonize_features(struct sk_buff *skb,
2484 netdev_features_t features)
2486 if (skb->ip_summed != CHECKSUM_NONE &&
2487 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2488 features &= ~NETIF_F_ALL_CSUM;
2489 } else if (illegal_highdma(skb->dev, skb)) {
2490 features &= ~NETIF_F_SG;
2496 netdev_features_t netif_skb_features(struct sk_buff *skb)
2498 __be16 protocol = skb->protocol;
2499 netdev_features_t features = skb->dev->features;
2501 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2502 features &= ~NETIF_F_GSO_MASK;
2504 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2505 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2506 protocol = veh->h_vlan_encapsulated_proto;
2507 } else if (!vlan_tx_tag_present(skb)) {
2508 return harmonize_features(skb, features);
2511 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2512 NETIF_F_HW_VLAN_STAG_TX);
2514 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2515 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2516 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2517 NETIF_F_HW_VLAN_STAG_TX;
2519 return harmonize_features(skb, features);
2521 EXPORT_SYMBOL(netif_skb_features);
2524 * Returns true if either:
2525 * 1. skb has frag_list and the device doesn't support FRAGLIST, or
2526 * 2. skb is fragmented and the device does not support SG.
2528 static inline int skb_needs_linearize(struct sk_buff *skb,
2529 netdev_features_t features)
2531 return skb_is_nonlinear(skb) &&
2532 ((skb_has_frag_list(skb) &&
2533 !(features & NETIF_F_FRAGLIST)) ||
2534 (skb_shinfo(skb)->nr_frags &&
2535 !(features & NETIF_F_SG)));
2538 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2539 struct netdev_queue *txq)
2541 const struct net_device_ops *ops = dev->netdev_ops;
2542 int rc = NETDEV_TX_OK;
2543 unsigned int skb_len;
2545 if (likely(!skb->next)) {
2546 netdev_features_t features;
2549 * If device doesn't need skb->dst, release it right now while
2550 * its hot in this cpu cache
2552 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2555 features = netif_skb_features(skb);
2557 if (vlan_tx_tag_present(skb) &&
2558 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2559 skb = __vlan_put_tag(skb, skb->vlan_proto,
2560 vlan_tx_tag_get(skb));
2567 /* If encapsulation offload request, verify we are testing
2568 * hardware encapsulation features instead of standard
2569 * features for the netdev
2571 if (skb->encapsulation)
2572 features &= dev->hw_enc_features;
2574 if (netif_needs_gso(skb, features)) {
2575 if (unlikely(dev_gso_segment(skb, features)))
2580 if (skb_needs_linearize(skb, features) &&
2581 __skb_linearize(skb))
2584 /* If packet is not checksummed and device does not
2585 * support checksumming for this protocol, complete
2586 * checksumming here.
2588 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2589 if (skb->encapsulation)
2590 skb_set_inner_transport_header(skb,
2591 skb_checksum_start_offset(skb));
2593 skb_set_transport_header(skb,
2594 skb_checksum_start_offset(skb));
2595 if (!(features & NETIF_F_ALL_CSUM) &&
2596 skb_checksum_help(skb))
2601 if (!list_empty(&ptype_all))
2602 dev_queue_xmit_nit(skb, dev);
2605 rc = ops->ndo_start_xmit(skb, dev);
2606 trace_net_dev_xmit(skb, rc, dev, skb_len);
2607 if (rc == NETDEV_TX_OK)
2608 txq_trans_update(txq);
2614 struct sk_buff *nskb = skb->next;
2616 skb->next = nskb->next;
2619 if (!list_empty(&ptype_all))
2620 dev_queue_xmit_nit(nskb, dev);
2622 skb_len = nskb->len;
2623 rc = ops->ndo_start_xmit(nskb, dev);
2624 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2625 if (unlikely(rc != NETDEV_TX_OK)) {
2626 if (rc & ~NETDEV_TX_MASK)
2627 goto out_kfree_gso_skb;
2628 nskb->next = skb->next;
2632 txq_trans_update(txq);
2633 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2634 return NETDEV_TX_BUSY;
2635 } while (skb->next);
2638 if (likely(skb->next == NULL)) {
2639 skb->destructor = DEV_GSO_CB(skb)->destructor;
2649 static void qdisc_pkt_len_init(struct sk_buff *skb)
2651 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2653 qdisc_skb_cb(skb)->pkt_len = skb->len;
2655 /* To get more precise estimation of bytes sent on wire,
2656 * we add to pkt_len the headers size of all segments
2658 if (shinfo->gso_size) {
2659 unsigned int hdr_len;
2660 u16 gso_segs = shinfo->gso_segs;
2662 /* mac layer + network layer */
2663 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2665 /* + transport layer */
2666 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2667 hdr_len += tcp_hdrlen(skb);
2669 hdr_len += sizeof(struct udphdr);
2671 if (shinfo->gso_type & SKB_GSO_DODGY)
2672 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2675 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2679 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2680 struct net_device *dev,
2681 struct netdev_queue *txq)
2683 spinlock_t *root_lock = qdisc_lock(q);
2687 qdisc_pkt_len_init(skb);
2688 qdisc_calculate_pkt_len(skb, q);
2690 * Heuristic to force contended enqueues to serialize on a
2691 * separate lock before trying to get qdisc main lock.
2692 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2693 * and dequeue packets faster.
2695 contended = qdisc_is_running(q);
2696 if (unlikely(contended))
2697 spin_lock(&q->busylock);
2699 spin_lock(root_lock);
2700 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2703 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2704 qdisc_run_begin(q)) {
2706 * This is a work-conserving queue; there are no old skbs
2707 * waiting to be sent out; and the qdisc is not running -
2708 * xmit the skb directly.
2710 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2713 qdisc_bstats_update(q, skb);
2715 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2716 if (unlikely(contended)) {
2717 spin_unlock(&q->busylock);
2724 rc = NET_XMIT_SUCCESS;
2727 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2728 if (qdisc_run_begin(q)) {
2729 if (unlikely(contended)) {
2730 spin_unlock(&q->busylock);
2736 spin_unlock(root_lock);
2737 if (unlikely(contended))
2738 spin_unlock(&q->busylock);
2742 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
2743 static void skb_update_prio(struct sk_buff *skb)
2745 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2747 if (!skb->priority && skb->sk && map) {
2748 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2750 if (prioidx < map->priomap_len)
2751 skb->priority = map->priomap[prioidx];
2755 #define skb_update_prio(skb)
2758 static DEFINE_PER_CPU(int, xmit_recursion);
2759 #define RECURSION_LIMIT 10
2762 * dev_loopback_xmit - loop back @skb
2763 * @skb: buffer to transmit
2765 int dev_loopback_xmit(struct sk_buff *skb)
2767 skb_reset_mac_header(skb);
2768 __skb_pull(skb, skb_network_offset(skb));
2769 skb->pkt_type = PACKET_LOOPBACK;
2770 skb->ip_summed = CHECKSUM_UNNECESSARY;
2771 WARN_ON(!skb_dst(skb));
2776 EXPORT_SYMBOL(dev_loopback_xmit);
2779 * dev_queue_xmit - transmit a buffer
2780 * @skb: buffer to transmit
2782 * Queue a buffer for transmission to a network device. The caller must
2783 * have set the device and priority and built the buffer before calling
2784 * this function. The function can be called from an interrupt.
2786 * A negative errno code is returned on a failure. A success does not
2787 * guarantee the frame will be transmitted as it may be dropped due
2788 * to congestion or traffic shaping.
2790 * -----------------------------------------------------------------------------------
2791 * I notice this method can also return errors from the queue disciplines,
2792 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2795 * Regardless of the return value, the skb is consumed, so it is currently
2796 * difficult to retry a send to this method. (You can bump the ref count
2797 * before sending to hold a reference for retry if you are careful.)
2799 * When calling this method, interrupts MUST be enabled. This is because
2800 * the BH enable code must have IRQs enabled so that it will not deadlock.
2803 int dev_queue_xmit(struct sk_buff *skb)
2805 struct net_device *dev = skb->dev;
2806 struct netdev_queue *txq;
2810 skb_reset_mac_header(skb);
2812 /* Disable soft irqs for various locks below. Also
2813 * stops preemption for RCU.
2817 skb_update_prio(skb);
2819 txq = netdev_pick_tx(dev, skb);
2820 q = rcu_dereference_bh(txq->qdisc);
2822 #ifdef CONFIG_NET_CLS_ACT
2823 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2825 trace_net_dev_queue(skb);
2827 rc = __dev_xmit_skb(skb, q, dev, txq);
2831 /* The device has no queue. Common case for software devices:
2832 loopback, all the sorts of tunnels...
2834 Really, it is unlikely that netif_tx_lock protection is necessary
2835 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2837 However, it is possible, that they rely on protection
2840 Check this and shot the lock. It is not prone from deadlocks.
2841 Either shot noqueue qdisc, it is even simpler 8)
2843 if (dev->flags & IFF_UP) {
2844 int cpu = smp_processor_id(); /* ok because BHs are off */
2846 if (txq->xmit_lock_owner != cpu) {
2848 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2849 goto recursion_alert;
2851 HARD_TX_LOCK(dev, txq, cpu);
2853 if (!netif_xmit_stopped(txq)) {
2854 __this_cpu_inc(xmit_recursion);
2855 rc = dev_hard_start_xmit(skb, dev, txq);
2856 __this_cpu_dec(xmit_recursion);
2857 if (dev_xmit_complete(rc)) {
2858 HARD_TX_UNLOCK(dev, txq);
2862 HARD_TX_UNLOCK(dev, txq);
2863 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2866 /* Recursion is detected! It is possible,
2870 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2876 rcu_read_unlock_bh();
2881 rcu_read_unlock_bh();
2884 EXPORT_SYMBOL(dev_queue_xmit);
2887 /*=======================================================================
2889 =======================================================================*/
2891 int netdev_max_backlog __read_mostly = 1000;
2892 EXPORT_SYMBOL(netdev_max_backlog);
2894 int netdev_tstamp_prequeue __read_mostly = 1;
2895 int netdev_budget __read_mostly = 300;
2896 int weight_p __read_mostly = 64; /* old backlog weight */
2898 /* Called with irq disabled */
2899 static inline void ____napi_schedule(struct softnet_data *sd,
2900 struct napi_struct *napi)
2902 list_add_tail(&napi->poll_list, &sd->poll_list);
2903 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2908 /* One global table that all flow-based protocols share. */
2909 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2910 EXPORT_SYMBOL(rps_sock_flow_table);
2912 struct static_key rps_needed __read_mostly;
2914 static struct rps_dev_flow *
2915 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2916 struct rps_dev_flow *rflow, u16 next_cpu)
2918 if (next_cpu != RPS_NO_CPU) {
2919 #ifdef CONFIG_RFS_ACCEL
2920 struct netdev_rx_queue *rxqueue;
2921 struct rps_dev_flow_table *flow_table;
2922 struct rps_dev_flow *old_rflow;
2927 /* Should we steer this flow to a different hardware queue? */
2928 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2929 !(dev->features & NETIF_F_NTUPLE))
2931 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2932 if (rxq_index == skb_get_rx_queue(skb))
2935 rxqueue = dev->_rx + rxq_index;
2936 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2939 flow_id = skb->rxhash & flow_table->mask;
2940 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2941 rxq_index, flow_id);
2945 rflow = &flow_table->flows[flow_id];
2947 if (old_rflow->filter == rflow->filter)
2948 old_rflow->filter = RPS_NO_FILTER;
2952 per_cpu(softnet_data, next_cpu).input_queue_head;
2955 rflow->cpu = next_cpu;
2960 * get_rps_cpu is called from netif_receive_skb and returns the target
2961 * CPU from the RPS map of the receiving queue for a given skb.
2962 * rcu_read_lock must be held on entry.
2964 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2965 struct rps_dev_flow **rflowp)
2967 struct netdev_rx_queue *rxqueue;
2968 struct rps_map *map;
2969 struct rps_dev_flow_table *flow_table;
2970 struct rps_sock_flow_table *sock_flow_table;
2974 if (skb_rx_queue_recorded(skb)) {
2975 u16 index = skb_get_rx_queue(skb);
2976 if (unlikely(index >= dev->real_num_rx_queues)) {
2977 WARN_ONCE(dev->real_num_rx_queues > 1,
2978 "%s received packet on queue %u, but number "
2979 "of RX queues is %u\n",
2980 dev->name, index, dev->real_num_rx_queues);
2983 rxqueue = dev->_rx + index;
2987 map = rcu_dereference(rxqueue->rps_map);
2989 if (map->len == 1 &&
2990 !rcu_access_pointer(rxqueue->rps_flow_table)) {
2991 tcpu = map->cpus[0];
2992 if (cpu_online(tcpu))
2996 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3000 skb_reset_network_header(skb);
3001 if (!skb_get_rxhash(skb))
3004 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3005 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3006 if (flow_table && sock_flow_table) {
3008 struct rps_dev_flow *rflow;
3010 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3013 next_cpu = sock_flow_table->ents[skb->rxhash &
3014 sock_flow_table->mask];
3017 * If the desired CPU (where last recvmsg was done) is
3018 * different from current CPU (one in the rx-queue flow
3019 * table entry), switch if one of the following holds:
3020 * - Current CPU is unset (equal to RPS_NO_CPU).
3021 * - Current CPU is offline.
3022 * - The current CPU's queue tail has advanced beyond the
3023 * last packet that was enqueued using this table entry.
3024 * This guarantees that all previous packets for the flow
3025 * have been dequeued, thus preserving in order delivery.
3027 if (unlikely(tcpu != next_cpu) &&
3028 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3029 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3030 rflow->last_qtail)) >= 0)) {
3032 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3035 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3043 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3045 if (cpu_online(tcpu)) {
3055 #ifdef CONFIG_RFS_ACCEL
3058 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3059 * @dev: Device on which the filter was set
3060 * @rxq_index: RX queue index
3061 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3062 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3064 * Drivers that implement ndo_rx_flow_steer() should periodically call
3065 * this function for each installed filter and remove the filters for
3066 * which it returns %true.
3068 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3069 u32 flow_id, u16 filter_id)
3071 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3072 struct rps_dev_flow_table *flow_table;
3073 struct rps_dev_flow *rflow;
3078 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3079 if (flow_table && flow_id <= flow_table->mask) {
3080 rflow = &flow_table->flows[flow_id];
3081 cpu = ACCESS_ONCE(rflow->cpu);
3082 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3083 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3084 rflow->last_qtail) <
3085 (int)(10 * flow_table->mask)))
3091 EXPORT_SYMBOL(rps_may_expire_flow);
3093 #endif /* CONFIG_RFS_ACCEL */
3095 /* Called from hardirq (IPI) context */
3096 static void rps_trigger_softirq(void *data)
3098 struct softnet_data *sd = data;
3100 ____napi_schedule(sd, &sd->backlog);
3104 #endif /* CONFIG_RPS */
3107 * Check if this softnet_data structure is another cpu one
3108 * If yes, queue it to our IPI list and return 1
3111 static int rps_ipi_queued(struct softnet_data *sd)
3114 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3117 sd->rps_ipi_next = mysd->rps_ipi_list;
3118 mysd->rps_ipi_list = sd;
3120 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3123 #endif /* CONFIG_RPS */
3127 #ifdef CONFIG_NET_FLOW_LIMIT
3128 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3131 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3133 #ifdef CONFIG_NET_FLOW_LIMIT
3134 struct sd_flow_limit *fl;
3135 struct softnet_data *sd;
3136 unsigned int old_flow, new_flow;
3138 if (qlen < (netdev_max_backlog >> 1))
3141 sd = &__get_cpu_var(softnet_data);
3144 fl = rcu_dereference(sd->flow_limit);
3146 new_flow = skb_get_rxhash(skb) & (fl->num_buckets - 1);
3147 old_flow = fl->history[fl->history_head];
3148 fl->history[fl->history_head] = new_flow;
3151 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3153 if (likely(fl->buckets[old_flow]))
3154 fl->buckets[old_flow]--;
3156 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3168 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3169 * queue (may be a remote CPU queue).
3171 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3172 unsigned int *qtail)
3174 struct softnet_data *sd;
3175 unsigned long flags;
3178 sd = &per_cpu(softnet_data, cpu);
3180 local_irq_save(flags);
3183 qlen = skb_queue_len(&sd->input_pkt_queue);
3184 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3185 if (skb_queue_len(&sd->input_pkt_queue)) {
3187 __skb_queue_tail(&sd->input_pkt_queue, skb);
3188 input_queue_tail_incr_save(sd, qtail);
3190 local_irq_restore(flags);
3191 return NET_RX_SUCCESS;
3194 /* Schedule NAPI for backlog device
3195 * We can use non atomic operation since we own the queue lock
3197 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3198 if (!rps_ipi_queued(sd))
3199 ____napi_schedule(sd, &sd->backlog);
3207 local_irq_restore(flags);
3209 atomic_long_inc(&skb->dev->rx_dropped);
3215 * netif_rx - post buffer to the network code
3216 * @skb: buffer to post
3218 * This function receives a packet from a device driver and queues it for
3219 * the upper (protocol) levels to process. It always succeeds. The buffer
3220 * may be dropped during processing for congestion control or by the
3224 * NET_RX_SUCCESS (no congestion)
3225 * NET_RX_DROP (packet was dropped)
3229 int netif_rx(struct sk_buff *skb)
3233 /* if netpoll wants it, pretend we never saw it */
3234 if (netpoll_rx(skb))
3237 net_timestamp_check(netdev_tstamp_prequeue, skb);
3239 trace_netif_rx(skb);
3241 if (static_key_false(&rps_needed)) {
3242 struct rps_dev_flow voidflow, *rflow = &voidflow;
3248 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3250 cpu = smp_processor_id();
3252 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3260 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3265 EXPORT_SYMBOL(netif_rx);
3267 int netif_rx_ni(struct sk_buff *skb)
3272 err = netif_rx(skb);
3273 if (local_softirq_pending())
3279 EXPORT_SYMBOL(netif_rx_ni);
3281 static void net_tx_action(struct softirq_action *h)
3283 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3285 if (sd->completion_queue) {
3286 struct sk_buff *clist;
3288 local_irq_disable();
3289 clist = sd->completion_queue;
3290 sd->completion_queue = NULL;
3294 struct sk_buff *skb = clist;
3295 clist = clist->next;
3297 WARN_ON(atomic_read(&skb->users));
3298 trace_kfree_skb(skb, net_tx_action);
3303 if (sd->output_queue) {
3306 local_irq_disable();
3307 head = sd->output_queue;
3308 sd->output_queue = NULL;
3309 sd->output_queue_tailp = &sd->output_queue;
3313 struct Qdisc *q = head;
3314 spinlock_t *root_lock;
3316 head = head->next_sched;
3318 root_lock = qdisc_lock(q);
3319 if (spin_trylock(root_lock)) {
3320 smp_mb__before_clear_bit();
3321 clear_bit(__QDISC_STATE_SCHED,
3324 spin_unlock(root_lock);
3326 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3328 __netif_reschedule(q);
3330 smp_mb__before_clear_bit();
3331 clear_bit(__QDISC_STATE_SCHED,
3339 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3340 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3341 /* This hook is defined here for ATM LANE */
3342 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3343 unsigned char *addr) __read_mostly;
3344 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3347 #ifdef CONFIG_NET_CLS_ACT
3348 /* TODO: Maybe we should just force sch_ingress to be compiled in
3349 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3350 * a compare and 2 stores extra right now if we dont have it on
3351 * but have CONFIG_NET_CLS_ACT
3352 * NOTE: This doesn't stop any functionality; if you dont have
3353 * the ingress scheduler, you just can't add policies on ingress.
3356 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3358 struct net_device *dev = skb->dev;
3359 u32 ttl = G_TC_RTTL(skb->tc_verd);
3360 int result = TC_ACT_OK;
3363 if (unlikely(MAX_RED_LOOP < ttl++)) {
3364 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3365 skb->skb_iif, dev->ifindex);
3369 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3370 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3373 if (q != &noop_qdisc) {
3374 spin_lock(qdisc_lock(q));
3375 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3376 result = qdisc_enqueue_root(skb, q);
3377 spin_unlock(qdisc_lock(q));
3383 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3384 struct packet_type **pt_prev,
3385 int *ret, struct net_device *orig_dev)
3387 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3389 if (!rxq || rxq->qdisc == &noop_qdisc)
3393 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3397 switch (ing_filter(skb, rxq)) {
3411 * netdev_rx_handler_register - register receive handler
3412 * @dev: device to register a handler for
3413 * @rx_handler: receive handler to register
3414 * @rx_handler_data: data pointer that is used by rx handler
3416 * Register a receive hander for a device. This handler will then be
3417 * called from __netif_receive_skb. A negative errno code is returned
3420 * The caller must hold the rtnl_mutex.
3422 * For a general description of rx_handler, see enum rx_handler_result.
3424 int netdev_rx_handler_register(struct net_device *dev,
3425 rx_handler_func_t *rx_handler,
3426 void *rx_handler_data)
3430 if (dev->rx_handler)
3433 /* Note: rx_handler_data must be set before rx_handler */
3434 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3435 rcu_assign_pointer(dev->rx_handler, rx_handler);
3439 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3442 * netdev_rx_handler_unregister - unregister receive handler
3443 * @dev: device to unregister a handler from
3445 * Unregister a receive handler from a device.
3447 * The caller must hold the rtnl_mutex.
3449 void netdev_rx_handler_unregister(struct net_device *dev)
3453 RCU_INIT_POINTER(dev->rx_handler, NULL);
3454 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3455 * section has a guarantee to see a non NULL rx_handler_data
3459 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3461 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3464 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3465 * the special handling of PFMEMALLOC skbs.
3467 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3469 switch (skb->protocol) {
3470 case __constant_htons(ETH_P_ARP):
3471 case __constant_htons(ETH_P_IP):
3472 case __constant_htons(ETH_P_IPV6):
3473 case __constant_htons(ETH_P_8021Q):
3474 case __constant_htons(ETH_P_8021AD):
3481 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3483 struct packet_type *ptype, *pt_prev;
3484 rx_handler_func_t *rx_handler;
3485 struct net_device *orig_dev;
3486 struct net_device *null_or_dev;
3487 bool deliver_exact = false;
3488 int ret = NET_RX_DROP;
3491 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3493 trace_netif_receive_skb(skb);
3495 /* if we've gotten here through NAPI, check netpoll */
3496 if (netpoll_receive_skb(skb))
3499 orig_dev = skb->dev;
3501 skb_reset_network_header(skb);
3502 if (!skb_transport_header_was_set(skb))
3503 skb_reset_transport_header(skb);
3504 skb_reset_mac_len(skb);
3511 skb->skb_iif = skb->dev->ifindex;
3513 __this_cpu_inc(softnet_data.processed);
3515 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3516 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3517 skb = vlan_untag(skb);
3522 #ifdef CONFIG_NET_CLS_ACT
3523 if (skb->tc_verd & TC_NCLS) {
3524 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3532 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3533 if (!ptype->dev || ptype->dev == skb->dev) {
3535 ret = deliver_skb(skb, pt_prev, orig_dev);
3541 #ifdef CONFIG_NET_CLS_ACT
3542 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3548 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3551 if (vlan_tx_tag_present(skb)) {
3553 ret = deliver_skb(skb, pt_prev, orig_dev);
3556 if (vlan_do_receive(&skb))
3558 else if (unlikely(!skb))
3562 rx_handler = rcu_dereference(skb->dev->rx_handler);
3565 ret = deliver_skb(skb, pt_prev, orig_dev);
3568 switch (rx_handler(&skb)) {
3569 case RX_HANDLER_CONSUMED:
3570 ret = NET_RX_SUCCESS;
3572 case RX_HANDLER_ANOTHER:
3574 case RX_HANDLER_EXACT:
3575 deliver_exact = true;
3576 case RX_HANDLER_PASS:
3583 if (vlan_tx_nonzero_tag_present(skb))
3584 skb->pkt_type = PACKET_OTHERHOST;
3586 /* deliver only exact match when indicated */
3587 null_or_dev = deliver_exact ? skb->dev : NULL;
3589 type = skb->protocol;
3590 list_for_each_entry_rcu(ptype,
3591 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3592 if (ptype->type == type &&
3593 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3594 ptype->dev == orig_dev)) {
3596 ret = deliver_skb(skb, pt_prev, orig_dev);
3602 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3605 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3608 atomic_long_inc(&skb->dev->rx_dropped);
3610 /* Jamal, now you will not able to escape explaining
3611 * me how you were going to use this. :-)
3622 static int __netif_receive_skb(struct sk_buff *skb)
3626 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3627 unsigned long pflags = current->flags;
3630 * PFMEMALLOC skbs are special, they should
3631 * - be delivered to SOCK_MEMALLOC sockets only
3632 * - stay away from userspace
3633 * - have bounded memory usage
3635 * Use PF_MEMALLOC as this saves us from propagating the allocation
3636 * context down to all allocation sites.
3638 current->flags |= PF_MEMALLOC;
3639 ret = __netif_receive_skb_core(skb, true);
3640 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3642 ret = __netif_receive_skb_core(skb, false);
3648 * netif_receive_skb - process receive buffer from network
3649 * @skb: buffer to process
3651 * netif_receive_skb() is the main receive data processing function.
3652 * It always succeeds. The buffer may be dropped during processing
3653 * for congestion control or by the protocol layers.
3655 * This function may only be called from softirq context and interrupts
3656 * should be enabled.
3658 * Return values (usually ignored):
3659 * NET_RX_SUCCESS: no congestion
3660 * NET_RX_DROP: packet was dropped
3662 int netif_receive_skb(struct sk_buff *skb)
3664 net_timestamp_check(netdev_tstamp_prequeue, skb);
3666 if (skb_defer_rx_timestamp(skb))
3667 return NET_RX_SUCCESS;
3670 if (static_key_false(&rps_needed)) {
3671 struct rps_dev_flow voidflow, *rflow = &voidflow;
3676 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3679 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3686 return __netif_receive_skb(skb);
3688 EXPORT_SYMBOL(netif_receive_skb);
3690 /* Network device is going away, flush any packets still pending
3691 * Called with irqs disabled.
3693 static void flush_backlog(void *arg)
3695 struct net_device *dev = arg;
3696 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3697 struct sk_buff *skb, *tmp;
3700 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3701 if (skb->dev == dev) {
3702 __skb_unlink(skb, &sd->input_pkt_queue);
3704 input_queue_head_incr(sd);
3709 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3710 if (skb->dev == dev) {
3711 __skb_unlink(skb, &sd->process_queue);
3713 input_queue_head_incr(sd);
3718 static int napi_gro_complete(struct sk_buff *skb)
3720 struct packet_offload *ptype;
3721 __be16 type = skb->protocol;
3722 struct list_head *head = &offload_base;
3725 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3727 if (NAPI_GRO_CB(skb)->count == 1) {
3728 skb_shinfo(skb)->gso_size = 0;
3733 list_for_each_entry_rcu(ptype, head, list) {
3734 if (ptype->type != type || !ptype->callbacks.gro_complete)
3737 err = ptype->callbacks.gro_complete(skb);
3743 WARN_ON(&ptype->list == head);
3745 return NET_RX_SUCCESS;
3749 return netif_receive_skb(skb);
3752 /* napi->gro_list contains packets ordered by age.
3753 * youngest packets at the head of it.
3754 * Complete skbs in reverse order to reduce latencies.
3756 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3758 struct sk_buff *skb, *prev = NULL;
3760 /* scan list and build reverse chain */
3761 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3766 for (skb = prev; skb; skb = prev) {
3769 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3773 napi_gro_complete(skb);
3777 napi->gro_list = NULL;
3779 EXPORT_SYMBOL(napi_gro_flush);
3781 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3784 unsigned int maclen = skb->dev->hard_header_len;
3786 for (p = napi->gro_list; p; p = p->next) {
3787 unsigned long diffs;
3789 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3790 diffs |= p->vlan_tci ^ skb->vlan_tci;
3791 if (maclen == ETH_HLEN)
3792 diffs |= compare_ether_header(skb_mac_header(p),
3793 skb_gro_mac_header(skb));
3795 diffs = memcmp(skb_mac_header(p),
3796 skb_gro_mac_header(skb),
3798 NAPI_GRO_CB(p)->same_flow = !diffs;
3799 NAPI_GRO_CB(p)->flush = 0;
3803 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3805 struct sk_buff **pp = NULL;
3806 struct packet_offload *ptype;
3807 __be16 type = skb->protocol;
3808 struct list_head *head = &offload_base;
3810 enum gro_result ret;
3812 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3815 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3818 gro_list_prepare(napi, skb);
3821 list_for_each_entry_rcu(ptype, head, list) {
3822 if (ptype->type != type || !ptype->callbacks.gro_receive)
3825 skb_set_network_header(skb, skb_gro_offset(skb));
3826 skb_reset_mac_len(skb);
3827 NAPI_GRO_CB(skb)->same_flow = 0;
3828 NAPI_GRO_CB(skb)->flush = 0;
3829 NAPI_GRO_CB(skb)->free = 0;
3831 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3836 if (&ptype->list == head)
3839 same_flow = NAPI_GRO_CB(skb)->same_flow;
3840 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3843 struct sk_buff *nskb = *pp;
3847 napi_gro_complete(nskb);
3854 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3858 NAPI_GRO_CB(skb)->count = 1;
3859 NAPI_GRO_CB(skb)->age = jiffies;
3860 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3861 skb->next = napi->gro_list;
3862 napi->gro_list = skb;
3866 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3867 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3869 BUG_ON(skb->end - skb->tail < grow);
3871 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3874 skb->data_len -= grow;
3876 skb_shinfo(skb)->frags[0].page_offset += grow;
3877 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3879 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3880 skb_frag_unref(skb, 0);
3881 memmove(skb_shinfo(skb)->frags,
3882 skb_shinfo(skb)->frags + 1,
3883 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3896 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3900 if (netif_receive_skb(skb))
3908 case GRO_MERGED_FREE:
3909 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
3910 kmem_cache_free(skbuff_head_cache, skb);
3923 static void skb_gro_reset_offset(struct sk_buff *skb)
3925 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3926 const skb_frag_t *frag0 = &pinfo->frags[0];
3928 NAPI_GRO_CB(skb)->data_offset = 0;
3929 NAPI_GRO_CB(skb)->frag0 = NULL;
3930 NAPI_GRO_CB(skb)->frag0_len = 0;
3932 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3934 !PageHighMem(skb_frag_page(frag0))) {
3935 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3936 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3940 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3942 skb_gro_reset_offset(skb);
3944 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
3946 EXPORT_SYMBOL(napi_gro_receive);
3948 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
3950 __skb_pull(skb, skb_headlen(skb));
3951 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
3952 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
3954 skb->dev = napi->dev;
3960 struct sk_buff *napi_get_frags(struct napi_struct *napi)
3962 struct sk_buff *skb = napi->skb;
3965 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
3971 EXPORT_SYMBOL(napi_get_frags);
3973 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
3979 skb->protocol = eth_type_trans(skb, skb->dev);
3981 if (ret == GRO_HELD)
3982 skb_gro_pull(skb, -ETH_HLEN);
3983 else if (netif_receive_skb(skb))
3988 case GRO_MERGED_FREE:
3989 napi_reuse_skb(napi, skb);
3999 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4001 struct sk_buff *skb = napi->skb;
4008 skb_reset_mac_header(skb);
4009 skb_gro_reset_offset(skb);
4011 off = skb_gro_offset(skb);
4012 hlen = off + sizeof(*eth);
4013 eth = skb_gro_header_fast(skb, off);
4014 if (skb_gro_header_hard(skb, hlen)) {
4015 eth = skb_gro_header_slow(skb, hlen, off);
4016 if (unlikely(!eth)) {
4017 napi_reuse_skb(napi, skb);
4023 skb_gro_pull(skb, sizeof(*eth));
4026 * This works because the only protocols we care about don't require
4027 * special handling. We'll fix it up properly at the end.
4029 skb->protocol = eth->h_proto;
4035 gro_result_t napi_gro_frags(struct napi_struct *napi)
4037 struct sk_buff *skb = napi_frags_skb(napi);
4042 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4044 EXPORT_SYMBOL(napi_gro_frags);
4047 * net_rps_action sends any pending IPI's for rps.
4048 * Note: called with local irq disabled, but exits with local irq enabled.
4050 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4053 struct softnet_data *remsd = sd->rps_ipi_list;
4056 sd->rps_ipi_list = NULL;
4060 /* Send pending IPI's to kick RPS processing on remote cpus. */
4062 struct softnet_data *next = remsd->rps_ipi_next;
4064 if (cpu_online(remsd->cpu))
4065 __smp_call_function_single(remsd->cpu,
4074 static int process_backlog(struct napi_struct *napi, int quota)
4077 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4080 /* Check if we have pending ipi, its better to send them now,
4081 * not waiting net_rx_action() end.
4083 if (sd->rps_ipi_list) {
4084 local_irq_disable();
4085 net_rps_action_and_irq_enable(sd);
4088 napi->weight = weight_p;
4089 local_irq_disable();
4090 while (work < quota) {
4091 struct sk_buff *skb;
4094 while ((skb = __skb_dequeue(&sd->process_queue))) {
4096 __netif_receive_skb(skb);
4097 local_irq_disable();
4098 input_queue_head_incr(sd);
4099 if (++work >= quota) {
4106 qlen = skb_queue_len(&sd->input_pkt_queue);
4108 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4109 &sd->process_queue);
4111 if (qlen < quota - work) {
4113 * Inline a custom version of __napi_complete().
4114 * only current cpu owns and manipulates this napi,
4115 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4116 * we can use a plain write instead of clear_bit(),
4117 * and we dont need an smp_mb() memory barrier.
4119 list_del(&napi->poll_list);
4122 quota = work + qlen;
4132 * __napi_schedule - schedule for receive
4133 * @n: entry to schedule
4135 * The entry's receive function will be scheduled to run
4137 void __napi_schedule(struct napi_struct *n)
4139 unsigned long flags;
4141 local_irq_save(flags);
4142 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4143 local_irq_restore(flags);
4145 EXPORT_SYMBOL(__napi_schedule);
4147 void __napi_complete(struct napi_struct *n)
4149 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4150 BUG_ON(n->gro_list);
4152 list_del(&n->poll_list);
4153 smp_mb__before_clear_bit();
4154 clear_bit(NAPI_STATE_SCHED, &n->state);
4156 EXPORT_SYMBOL(__napi_complete);
4158 void napi_complete(struct napi_struct *n)
4160 unsigned long flags;
4163 * don't let napi dequeue from the cpu poll list
4164 * just in case its running on a different cpu
4166 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4169 napi_gro_flush(n, false);
4170 local_irq_save(flags);
4172 local_irq_restore(flags);
4174 EXPORT_SYMBOL(napi_complete);
4176 /* must be called under rcu_read_lock(), as we dont take a reference */
4177 struct napi_struct *napi_by_id(unsigned int napi_id)
4179 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4180 struct napi_struct *napi;
4182 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4183 if (napi->napi_id == napi_id)
4188 EXPORT_SYMBOL_GPL(napi_by_id);
4190 void napi_hash_add(struct napi_struct *napi)
4192 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4194 spin_lock(&napi_hash_lock);
4196 /* 0 is not a valid id, we also skip an id that is taken
4197 * we expect both events to be extremely rare
4200 while (!napi->napi_id) {
4201 napi->napi_id = ++napi_gen_id;
4202 if (napi_by_id(napi->napi_id))
4206 hlist_add_head_rcu(&napi->napi_hash_node,
4207 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4209 spin_unlock(&napi_hash_lock);
4212 EXPORT_SYMBOL_GPL(napi_hash_add);
4214 /* Warning : caller is responsible to make sure rcu grace period
4215 * is respected before freeing memory containing @napi
4217 void napi_hash_del(struct napi_struct *napi)
4219 spin_lock(&napi_hash_lock);
4221 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4222 hlist_del_rcu(&napi->napi_hash_node);
4224 spin_unlock(&napi_hash_lock);
4226 EXPORT_SYMBOL_GPL(napi_hash_del);
4228 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4229 int (*poll)(struct napi_struct *, int), int weight)
4231 INIT_LIST_HEAD(&napi->poll_list);
4232 napi->gro_count = 0;
4233 napi->gro_list = NULL;
4236 if (weight > NAPI_POLL_WEIGHT)
4237 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4239 napi->weight = weight;
4240 list_add(&napi->dev_list, &dev->napi_list);
4242 #ifdef CONFIG_NETPOLL
4243 spin_lock_init(&napi->poll_lock);
4244 napi->poll_owner = -1;
4246 set_bit(NAPI_STATE_SCHED, &napi->state);
4248 EXPORT_SYMBOL(netif_napi_add);
4250 void netif_napi_del(struct napi_struct *napi)
4252 struct sk_buff *skb, *next;
4254 list_del_init(&napi->dev_list);
4255 napi_free_frags(napi);
4257 for (skb = napi->gro_list; skb; skb = next) {
4263 napi->gro_list = NULL;
4264 napi->gro_count = 0;
4266 EXPORT_SYMBOL(netif_napi_del);
4268 static void net_rx_action(struct softirq_action *h)
4270 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4271 unsigned long time_limit = jiffies + 2;
4272 int budget = netdev_budget;
4275 local_irq_disable();
4277 while (!list_empty(&sd->poll_list)) {
4278 struct napi_struct *n;
4281 /* If softirq window is exhuasted then punt.
4282 * Allow this to run for 2 jiffies since which will allow
4283 * an average latency of 1.5/HZ.
4285 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4290 /* Even though interrupts have been re-enabled, this
4291 * access is safe because interrupts can only add new
4292 * entries to the tail of this list, and only ->poll()
4293 * calls can remove this head entry from the list.
4295 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4297 have = netpoll_poll_lock(n);
4301 /* This NAPI_STATE_SCHED test is for avoiding a race
4302 * with netpoll's poll_napi(). Only the entity which
4303 * obtains the lock and sees NAPI_STATE_SCHED set will
4304 * actually make the ->poll() call. Therefore we avoid
4305 * accidentally calling ->poll() when NAPI is not scheduled.
4308 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4309 work = n->poll(n, weight);
4313 WARN_ON_ONCE(work > weight);
4317 local_irq_disable();
4319 /* Drivers must not modify the NAPI state if they
4320 * consume the entire weight. In such cases this code
4321 * still "owns" the NAPI instance and therefore can
4322 * move the instance around on the list at-will.
4324 if (unlikely(work == weight)) {
4325 if (unlikely(napi_disable_pending(n))) {
4328 local_irq_disable();
4331 /* flush too old packets
4332 * If HZ < 1000, flush all packets.
4335 napi_gro_flush(n, HZ >= 1000);
4336 local_irq_disable();
4338 list_move_tail(&n->poll_list, &sd->poll_list);
4342 netpoll_poll_unlock(have);
4345 net_rps_action_and_irq_enable(sd);
4347 #ifdef CONFIG_NET_DMA
4349 * There may not be any more sk_buffs coming right now, so push
4350 * any pending DMA copies to hardware
4352 dma_issue_pending_all();
4359 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4363 struct netdev_upper {
4364 struct net_device *dev;
4366 struct list_head list;
4367 struct rcu_head rcu;
4368 struct list_head search_list;
4371 static void __append_search_uppers(struct list_head *search_list,
4372 struct net_device *dev)
4374 struct netdev_upper *upper;
4376 list_for_each_entry(upper, &dev->upper_dev_list, list) {
4377 /* check if this upper is not already in search list */
4378 if (list_empty(&upper->search_list))
4379 list_add_tail(&upper->search_list, search_list);
4383 static bool __netdev_search_upper_dev(struct net_device *dev,
4384 struct net_device *upper_dev)
4386 LIST_HEAD(search_list);
4387 struct netdev_upper *upper;
4388 struct netdev_upper *tmp;
4391 __append_search_uppers(&search_list, dev);
4392 list_for_each_entry(upper, &search_list, search_list) {
4393 if (upper->dev == upper_dev) {
4397 __append_search_uppers(&search_list, upper->dev);
4399 list_for_each_entry_safe(upper, tmp, &search_list, search_list)
4400 INIT_LIST_HEAD(&upper->search_list);
4404 static struct netdev_upper *__netdev_find_upper(struct net_device *dev,
4405 struct net_device *upper_dev)
4407 struct netdev_upper *upper;
4409 list_for_each_entry(upper, &dev->upper_dev_list, list) {
4410 if (upper->dev == upper_dev)
4417 * netdev_has_upper_dev - Check if device is linked to an upper device
4419 * @upper_dev: upper device to check
4421 * Find out if a device is linked to specified upper device and return true
4422 * in case it is. Note that this checks only immediate upper device,
4423 * not through a complete stack of devices. The caller must hold the RTNL lock.
4425 bool netdev_has_upper_dev(struct net_device *dev,
4426 struct net_device *upper_dev)
4430 return __netdev_find_upper(dev, upper_dev);
4432 EXPORT_SYMBOL(netdev_has_upper_dev);
4435 * netdev_has_any_upper_dev - Check if device is linked to some device
4438 * Find out if a device is linked to an upper device and return true in case
4439 * it is. The caller must hold the RTNL lock.
4441 bool netdev_has_any_upper_dev(struct net_device *dev)
4445 return !list_empty(&dev->upper_dev_list);
4447 EXPORT_SYMBOL(netdev_has_any_upper_dev);
4450 * netdev_master_upper_dev_get - Get master upper device
4453 * Find a master upper device and return pointer to it or NULL in case
4454 * it's not there. The caller must hold the RTNL lock.
4456 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4458 struct netdev_upper *upper;
4462 if (list_empty(&dev->upper_dev_list))
4465 upper = list_first_entry(&dev->upper_dev_list,
4466 struct netdev_upper, list);
4467 if (likely(upper->master))
4471 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4474 * netdev_master_upper_dev_get_rcu - Get master upper device
4477 * Find a master upper device and return pointer to it or NULL in case
4478 * it's not there. The caller must hold the RCU read lock.
4480 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4482 struct netdev_upper *upper;
4484 upper = list_first_or_null_rcu(&dev->upper_dev_list,
4485 struct netdev_upper, list);
4486 if (upper && likely(upper->master))
4490 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4492 static int __netdev_upper_dev_link(struct net_device *dev,
4493 struct net_device *upper_dev, bool master)
4495 struct netdev_upper *upper;
4499 if (dev == upper_dev)
4502 /* To prevent loops, check if dev is not upper device to upper_dev. */
4503 if (__netdev_search_upper_dev(upper_dev, dev))
4506 if (__netdev_find_upper(dev, upper_dev))
4509 if (master && netdev_master_upper_dev_get(dev))
4512 upper = kmalloc(sizeof(*upper), GFP_KERNEL);
4516 upper->dev = upper_dev;
4517 upper->master = master;
4518 INIT_LIST_HEAD(&upper->search_list);
4520 /* Ensure that master upper link is always the first item in list. */
4522 list_add_rcu(&upper->list, &dev->upper_dev_list);
4524 list_add_tail_rcu(&upper->list, &dev->upper_dev_list);
4525 dev_hold(upper_dev);
4526 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4531 * netdev_upper_dev_link - Add a link to the upper device
4533 * @upper_dev: new upper device
4535 * Adds a link to device which is upper to this one. The caller must hold
4536 * the RTNL lock. On a failure a negative errno code is returned.
4537 * On success the reference counts are adjusted and the function
4540 int netdev_upper_dev_link(struct net_device *dev,
4541 struct net_device *upper_dev)
4543 return __netdev_upper_dev_link(dev, upper_dev, false);
4545 EXPORT_SYMBOL(netdev_upper_dev_link);
4548 * netdev_master_upper_dev_link - Add a master link to the upper device
4550 * @upper_dev: new upper device
4552 * Adds a link to device which is upper to this one. In this case, only
4553 * one master upper device can be linked, although other non-master devices
4554 * might be linked as well. The caller must hold the RTNL lock.
4555 * On a failure a negative errno code is returned. On success the reference
4556 * counts are adjusted and the function returns zero.
4558 int netdev_master_upper_dev_link(struct net_device *dev,
4559 struct net_device *upper_dev)
4561 return __netdev_upper_dev_link(dev, upper_dev, true);
4563 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4566 * netdev_upper_dev_unlink - Removes a link to upper device
4568 * @upper_dev: new upper device
4570 * Removes a link to device which is upper to this one. The caller must hold
4573 void netdev_upper_dev_unlink(struct net_device *dev,
4574 struct net_device *upper_dev)
4576 struct netdev_upper *upper;
4580 upper = __netdev_find_upper(dev, upper_dev);
4583 list_del_rcu(&upper->list);
4585 kfree_rcu(upper, rcu);
4586 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4588 EXPORT_SYMBOL(netdev_upper_dev_unlink);
4590 static void dev_change_rx_flags(struct net_device *dev, int flags)
4592 const struct net_device_ops *ops = dev->netdev_ops;
4594 if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags)
4595 ops->ndo_change_rx_flags(dev, flags);
4598 static int __dev_set_promiscuity(struct net_device *dev, int inc)
4600 unsigned int old_flags = dev->flags;
4606 dev->flags |= IFF_PROMISC;
4607 dev->promiscuity += inc;
4608 if (dev->promiscuity == 0) {
4611 * If inc causes overflow, untouch promisc and return error.
4614 dev->flags &= ~IFF_PROMISC;
4616 dev->promiscuity -= inc;
4617 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
4622 if (dev->flags != old_flags) {
4623 pr_info("device %s %s promiscuous mode\n",
4625 dev->flags & IFF_PROMISC ? "entered" : "left");
4626 if (audit_enabled) {
4627 current_uid_gid(&uid, &gid);
4628 audit_log(current->audit_context, GFP_ATOMIC,
4629 AUDIT_ANOM_PROMISCUOUS,
4630 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
4631 dev->name, (dev->flags & IFF_PROMISC),
4632 (old_flags & IFF_PROMISC),
4633 from_kuid(&init_user_ns, audit_get_loginuid(current)),
4634 from_kuid(&init_user_ns, uid),
4635 from_kgid(&init_user_ns, gid),
4636 audit_get_sessionid(current));
4639 dev_change_rx_flags(dev, IFF_PROMISC);
4645 * dev_set_promiscuity - update promiscuity count on a device
4649 * Add or remove promiscuity from a device. While the count in the device
4650 * remains above zero the interface remains promiscuous. Once it hits zero
4651 * the device reverts back to normal filtering operation. A negative inc
4652 * value is used to drop promiscuity on the device.
4653 * Return 0 if successful or a negative errno code on error.
4655 int dev_set_promiscuity(struct net_device *dev, int inc)
4657 unsigned int old_flags = dev->flags;
4660 err = __dev_set_promiscuity(dev, inc);
4663 if (dev->flags != old_flags)
4664 dev_set_rx_mode(dev);
4667 EXPORT_SYMBOL(dev_set_promiscuity);
4670 * dev_set_allmulti - update allmulti count on a device
4674 * Add or remove reception of all multicast frames to a device. While the
4675 * count in the device remains above zero the interface remains listening
4676 * to all interfaces. Once it hits zero the device reverts back to normal
4677 * filtering operation. A negative @inc value is used to drop the counter
4678 * when releasing a resource needing all multicasts.
4679 * Return 0 if successful or a negative errno code on error.
4682 int dev_set_allmulti(struct net_device *dev, int inc)
4684 unsigned int old_flags = dev->flags;
4688 dev->flags |= IFF_ALLMULTI;
4689 dev->allmulti += inc;
4690 if (dev->allmulti == 0) {
4693 * If inc causes overflow, untouch allmulti and return error.
4696 dev->flags &= ~IFF_ALLMULTI;
4698 dev->allmulti -= inc;
4699 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
4704 if (dev->flags ^ old_flags) {
4705 dev_change_rx_flags(dev, IFF_ALLMULTI);
4706 dev_set_rx_mode(dev);
4710 EXPORT_SYMBOL(dev_set_allmulti);
4713 * Upload unicast and multicast address lists to device and
4714 * configure RX filtering. When the device doesn't support unicast
4715 * filtering it is put in promiscuous mode while unicast addresses
4718 void __dev_set_rx_mode(struct net_device *dev)
4720 const struct net_device_ops *ops = dev->netdev_ops;
4722 /* dev_open will call this function so the list will stay sane. */
4723 if (!(dev->flags&IFF_UP))
4726 if (!netif_device_present(dev))
4729 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
4730 /* Unicast addresses changes may only happen under the rtnl,
4731 * therefore calling __dev_set_promiscuity here is safe.
4733 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
4734 __dev_set_promiscuity(dev, 1);
4735 dev->uc_promisc = true;
4736 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
4737 __dev_set_promiscuity(dev, -1);
4738 dev->uc_promisc = false;
4742 if (ops->ndo_set_rx_mode)
4743 ops->ndo_set_rx_mode(dev);
4746 void dev_set_rx_mode(struct net_device *dev)
4748 netif_addr_lock_bh(dev);
4749 __dev_set_rx_mode(dev);
4750 netif_addr_unlock_bh(dev);
4754 * dev_get_flags - get flags reported to userspace
4757 * Get the combination of flag bits exported through APIs to userspace.
4759 unsigned int dev_get_flags(const struct net_device *dev)
4763 flags = (dev->flags & ~(IFF_PROMISC |
4768 (dev->gflags & (IFF_PROMISC |
4771 if (netif_running(dev)) {
4772 if (netif_oper_up(dev))
4773 flags |= IFF_RUNNING;
4774 if (netif_carrier_ok(dev))
4775 flags |= IFF_LOWER_UP;
4776 if (netif_dormant(dev))
4777 flags |= IFF_DORMANT;
4782 EXPORT_SYMBOL(dev_get_flags);
4784 int __dev_change_flags(struct net_device *dev, unsigned int flags)
4786 unsigned int old_flags = dev->flags;
4792 * Set the flags on our device.
4795 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
4796 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
4798 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
4802 * Load in the correct multicast list now the flags have changed.
4805 if ((old_flags ^ flags) & IFF_MULTICAST)
4806 dev_change_rx_flags(dev, IFF_MULTICAST);
4808 dev_set_rx_mode(dev);
4811 * Have we downed the interface. We handle IFF_UP ourselves
4812 * according to user attempts to set it, rather than blindly
4817 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
4818 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
4821 dev_set_rx_mode(dev);
4824 if ((flags ^ dev->gflags) & IFF_PROMISC) {
4825 int inc = (flags & IFF_PROMISC) ? 1 : -1;
4827 dev->gflags ^= IFF_PROMISC;
4828 dev_set_promiscuity(dev, inc);
4831 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
4832 is important. Some (broken) drivers set IFF_PROMISC, when
4833 IFF_ALLMULTI is requested not asking us and not reporting.
4835 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
4836 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
4838 dev->gflags ^= IFF_ALLMULTI;
4839 dev_set_allmulti(dev, inc);
4845 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags)
4847 unsigned int changes = dev->flags ^ old_flags;
4849 if (changes & IFF_UP) {
4850 if (dev->flags & IFF_UP)
4851 call_netdevice_notifiers(NETDEV_UP, dev);
4853 call_netdevice_notifiers(NETDEV_DOWN, dev);
4856 if (dev->flags & IFF_UP &&
4857 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
4858 struct netdev_notifier_change_info change_info;
4860 change_info.flags_changed = changes;
4861 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
4867 * dev_change_flags - change device settings
4869 * @flags: device state flags
4871 * Change settings on device based state flags. The flags are
4872 * in the userspace exported format.
4874 int dev_change_flags(struct net_device *dev, unsigned int flags)
4877 unsigned int changes, old_flags = dev->flags;
4879 ret = __dev_change_flags(dev, flags);
4883 changes = old_flags ^ dev->flags;
4885 rtmsg_ifinfo(RTM_NEWLINK, dev, changes);
4887 __dev_notify_flags(dev, old_flags);
4890 EXPORT_SYMBOL(dev_change_flags);
4893 * dev_set_mtu - Change maximum transfer unit
4895 * @new_mtu: new transfer unit
4897 * Change the maximum transfer size of the network device.
4899 int dev_set_mtu(struct net_device *dev, int new_mtu)
4901 const struct net_device_ops *ops = dev->netdev_ops;
4904 if (new_mtu == dev->mtu)
4907 /* MTU must be positive. */
4911 if (!netif_device_present(dev))
4915 if (ops->ndo_change_mtu)
4916 err = ops->ndo_change_mtu(dev, new_mtu);
4921 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
4924 EXPORT_SYMBOL(dev_set_mtu);
4927 * dev_set_group - Change group this device belongs to
4929 * @new_group: group this device should belong to
4931 void dev_set_group(struct net_device *dev, int new_group)
4933 dev->group = new_group;
4935 EXPORT_SYMBOL(dev_set_group);
4938 * dev_set_mac_address - Change Media Access Control Address
4942 * Change the hardware (MAC) address of the device
4944 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
4946 const struct net_device_ops *ops = dev->netdev_ops;
4949 if (!ops->ndo_set_mac_address)
4951 if (sa->sa_family != dev->type)
4953 if (!netif_device_present(dev))
4955 err = ops->ndo_set_mac_address(dev, sa);
4958 dev->addr_assign_type = NET_ADDR_SET;
4959 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
4960 add_device_randomness(dev->dev_addr, dev->addr_len);
4963 EXPORT_SYMBOL(dev_set_mac_address);
4966 * dev_change_carrier - Change device carrier
4968 * @new_carrier: new value
4970 * Change device carrier
4972 int dev_change_carrier(struct net_device *dev, bool new_carrier)
4974 const struct net_device_ops *ops = dev->netdev_ops;
4976 if (!ops->ndo_change_carrier)
4978 if (!netif_device_present(dev))
4980 return ops->ndo_change_carrier(dev, new_carrier);
4982 EXPORT_SYMBOL(dev_change_carrier);
4985 * dev_new_index - allocate an ifindex
4986 * @net: the applicable net namespace
4988 * Returns a suitable unique value for a new device interface
4989 * number. The caller must hold the rtnl semaphore or the
4990 * dev_base_lock to be sure it remains unique.
4992 static int dev_new_index(struct net *net)
4994 int ifindex = net->ifindex;
4998 if (!__dev_get_by_index(net, ifindex))
4999 return net->ifindex = ifindex;
5003 /* Delayed registration/unregisteration */
5004 static LIST_HEAD(net_todo_list);
5006 static void net_set_todo(struct net_device *dev)
5008 list_add_tail(&dev->todo_list, &net_todo_list);
5011 static void rollback_registered_many(struct list_head *head)
5013 struct net_device *dev, *tmp;
5015 BUG_ON(dev_boot_phase);
5018 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5019 /* Some devices call without registering
5020 * for initialization unwind. Remove those
5021 * devices and proceed with the remaining.
5023 if (dev->reg_state == NETREG_UNINITIALIZED) {
5024 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5028 list_del(&dev->unreg_list);
5031 dev->dismantle = true;
5032 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5035 /* If device is running, close it first. */
5036 dev_close_many(head);
5038 list_for_each_entry(dev, head, unreg_list) {
5039 /* And unlink it from device chain. */
5040 unlist_netdevice(dev);
5042 dev->reg_state = NETREG_UNREGISTERING;
5047 list_for_each_entry(dev, head, unreg_list) {
5048 /* Shutdown queueing discipline. */
5052 /* Notify protocols, that we are about to destroy
5053 this device. They should clean all the things.
5055 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5057 if (!dev->rtnl_link_ops ||
5058 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5059 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
5062 * Flush the unicast and multicast chains
5067 if (dev->netdev_ops->ndo_uninit)
5068 dev->netdev_ops->ndo_uninit(dev);
5070 /* Notifier chain MUST detach us all upper devices. */
5071 WARN_ON(netdev_has_any_upper_dev(dev));
5073 /* Remove entries from kobject tree */
5074 netdev_unregister_kobject(dev);
5076 /* Remove XPS queueing entries */
5077 netif_reset_xps_queues_gt(dev, 0);
5083 list_for_each_entry(dev, head, unreg_list)
5087 static void rollback_registered(struct net_device *dev)
5091 list_add(&dev->unreg_list, &single);
5092 rollback_registered_many(&single);
5096 static netdev_features_t netdev_fix_features(struct net_device *dev,
5097 netdev_features_t features)
5099 /* Fix illegal checksum combinations */
5100 if ((features & NETIF_F_HW_CSUM) &&
5101 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5102 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5103 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5106 /* TSO requires that SG is present as well. */
5107 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5108 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5109 features &= ~NETIF_F_ALL_TSO;
5112 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5113 !(features & NETIF_F_IP_CSUM)) {
5114 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5115 features &= ~NETIF_F_TSO;
5116 features &= ~NETIF_F_TSO_ECN;
5119 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5120 !(features & NETIF_F_IPV6_CSUM)) {
5121 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5122 features &= ~NETIF_F_TSO6;
5125 /* TSO ECN requires that TSO is present as well. */
5126 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5127 features &= ~NETIF_F_TSO_ECN;
5129 /* Software GSO depends on SG. */
5130 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5131 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5132 features &= ~NETIF_F_GSO;
5135 /* UFO needs SG and checksumming */
5136 if (features & NETIF_F_UFO) {
5137 /* maybe split UFO into V4 and V6? */
5138 if (!((features & NETIF_F_GEN_CSUM) ||
5139 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5140 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5142 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5143 features &= ~NETIF_F_UFO;
5146 if (!(features & NETIF_F_SG)) {
5148 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5149 features &= ~NETIF_F_UFO;
5156 int __netdev_update_features(struct net_device *dev)
5158 netdev_features_t features;
5163 features = netdev_get_wanted_features(dev);
5165 if (dev->netdev_ops->ndo_fix_features)
5166 features = dev->netdev_ops->ndo_fix_features(dev, features);
5168 /* driver might be less strict about feature dependencies */
5169 features = netdev_fix_features(dev, features);
5171 if (dev->features == features)
5174 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5175 &dev->features, &features);
5177 if (dev->netdev_ops->ndo_set_features)
5178 err = dev->netdev_ops->ndo_set_features(dev, features);
5180 if (unlikely(err < 0)) {
5182 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5183 err, &features, &dev->features);
5188 dev->features = features;
5194 * netdev_update_features - recalculate device features
5195 * @dev: the device to check
5197 * Recalculate dev->features set and send notifications if it
5198 * has changed. Should be called after driver or hardware dependent
5199 * conditions might have changed that influence the features.
5201 void netdev_update_features(struct net_device *dev)
5203 if (__netdev_update_features(dev))
5204 netdev_features_change(dev);
5206 EXPORT_SYMBOL(netdev_update_features);
5209 * netdev_change_features - recalculate device features
5210 * @dev: the device to check
5212 * Recalculate dev->features set and send notifications even
5213 * if they have not changed. Should be called instead of
5214 * netdev_update_features() if also dev->vlan_features might
5215 * have changed to allow the changes to be propagated to stacked
5218 void netdev_change_features(struct net_device *dev)
5220 __netdev_update_features(dev);
5221 netdev_features_change(dev);
5223 EXPORT_SYMBOL(netdev_change_features);
5226 * netif_stacked_transfer_operstate - transfer operstate
5227 * @rootdev: the root or lower level device to transfer state from
5228 * @dev: the device to transfer operstate to
5230 * Transfer operational state from root to device. This is normally
5231 * called when a stacking relationship exists between the root
5232 * device and the device(a leaf device).
5234 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5235 struct net_device *dev)
5237 if (rootdev->operstate == IF_OPER_DORMANT)
5238 netif_dormant_on(dev);
5240 netif_dormant_off(dev);
5242 if (netif_carrier_ok(rootdev)) {
5243 if (!netif_carrier_ok(dev))
5244 netif_carrier_on(dev);
5246 if (netif_carrier_ok(dev))
5247 netif_carrier_off(dev);
5250 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5253 static int netif_alloc_rx_queues(struct net_device *dev)
5255 unsigned int i, count = dev->num_rx_queues;
5256 struct netdev_rx_queue *rx;
5260 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5266 for (i = 0; i < count; i++)
5272 static void netdev_init_one_queue(struct net_device *dev,
5273 struct netdev_queue *queue, void *_unused)
5275 /* Initialize queue lock */
5276 spin_lock_init(&queue->_xmit_lock);
5277 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5278 queue->xmit_lock_owner = -1;
5279 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5282 dql_init(&queue->dql, HZ);
5286 static void netif_free_tx_queues(struct net_device *dev)
5288 if (is_vmalloc_addr(dev->_tx))
5294 static int netif_alloc_netdev_queues(struct net_device *dev)
5296 unsigned int count = dev->num_tx_queues;
5297 struct netdev_queue *tx;
5298 size_t sz = count * sizeof(*tx);
5300 BUG_ON(count < 1 || count > 0xffff);
5302 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5310 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5311 spin_lock_init(&dev->tx_global_lock);
5317 * register_netdevice - register a network device
5318 * @dev: device to register
5320 * Take a completed network device structure and add it to the kernel
5321 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5322 * chain. 0 is returned on success. A negative errno code is returned
5323 * on a failure to set up the device, or if the name is a duplicate.
5325 * Callers must hold the rtnl semaphore. You may want
5326 * register_netdev() instead of this.
5329 * The locking appears insufficient to guarantee two parallel registers
5330 * will not get the same name.
5333 int register_netdevice(struct net_device *dev)
5336 struct net *net = dev_net(dev);
5338 BUG_ON(dev_boot_phase);
5343 /* When net_device's are persistent, this will be fatal. */
5344 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5347 spin_lock_init(&dev->addr_list_lock);
5348 netdev_set_addr_lockdep_class(dev);
5352 ret = dev_get_valid_name(net, dev, dev->name);
5356 /* Init, if this function is available */
5357 if (dev->netdev_ops->ndo_init) {
5358 ret = dev->netdev_ops->ndo_init(dev);
5366 if (((dev->hw_features | dev->features) &
5367 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5368 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5369 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5370 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5377 dev->ifindex = dev_new_index(net);
5378 else if (__dev_get_by_index(net, dev->ifindex))
5381 if (dev->iflink == -1)
5382 dev->iflink = dev->ifindex;
5384 /* Transfer changeable features to wanted_features and enable
5385 * software offloads (GSO and GRO).
5387 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5388 dev->features |= NETIF_F_SOFT_FEATURES;
5389 dev->wanted_features = dev->features & dev->hw_features;
5391 /* Turn on no cache copy if HW is doing checksum */
5392 if (!(dev->flags & IFF_LOOPBACK)) {
5393 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5394 if (dev->features & NETIF_F_ALL_CSUM) {
5395 dev->wanted_features |= NETIF_F_NOCACHE_COPY;
5396 dev->features |= NETIF_F_NOCACHE_COPY;
5400 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5402 dev->vlan_features |= NETIF_F_HIGHDMA;
5404 /* Make NETIF_F_SG inheritable to tunnel devices.
5406 dev->hw_enc_features |= NETIF_F_SG;
5408 /* Make NETIF_F_SG inheritable to MPLS.
5410 dev->mpls_features |= NETIF_F_SG;
5412 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5413 ret = notifier_to_errno(ret);
5417 ret = netdev_register_kobject(dev);
5420 dev->reg_state = NETREG_REGISTERED;
5422 __netdev_update_features(dev);
5425 * Default initial state at registry is that the
5426 * device is present.
5429 set_bit(__LINK_STATE_PRESENT, &dev->state);
5431 linkwatch_init_dev(dev);
5433 dev_init_scheduler(dev);
5435 list_netdevice(dev);
5436 add_device_randomness(dev->dev_addr, dev->addr_len);
5438 /* If the device has permanent device address, driver should
5439 * set dev_addr and also addr_assign_type should be set to
5440 * NET_ADDR_PERM (default value).
5442 if (dev->addr_assign_type == NET_ADDR_PERM)
5443 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5445 /* Notify protocols, that a new device appeared. */
5446 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5447 ret = notifier_to_errno(ret);
5449 rollback_registered(dev);
5450 dev->reg_state = NETREG_UNREGISTERED;
5453 * Prevent userspace races by waiting until the network
5454 * device is fully setup before sending notifications.
5456 if (!dev->rtnl_link_ops ||
5457 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5458 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
5464 if (dev->netdev_ops->ndo_uninit)
5465 dev->netdev_ops->ndo_uninit(dev);
5468 EXPORT_SYMBOL(register_netdevice);
5471 * init_dummy_netdev - init a dummy network device for NAPI
5472 * @dev: device to init
5474 * This takes a network device structure and initialize the minimum
5475 * amount of fields so it can be used to schedule NAPI polls without
5476 * registering a full blown interface. This is to be used by drivers
5477 * that need to tie several hardware interfaces to a single NAPI
5478 * poll scheduler due to HW limitations.
5480 int init_dummy_netdev(struct net_device *dev)
5482 /* Clear everything. Note we don't initialize spinlocks
5483 * are they aren't supposed to be taken by any of the
5484 * NAPI code and this dummy netdev is supposed to be
5485 * only ever used for NAPI polls
5487 memset(dev, 0, sizeof(struct net_device));
5489 /* make sure we BUG if trying to hit standard
5490 * register/unregister code path
5492 dev->reg_state = NETREG_DUMMY;
5494 /* NAPI wants this */
5495 INIT_LIST_HEAD(&dev->napi_list);
5497 /* a dummy interface is started by default */
5498 set_bit(__LINK_STATE_PRESENT, &dev->state);
5499 set_bit(__LINK_STATE_START, &dev->state);
5501 /* Note : We dont allocate pcpu_refcnt for dummy devices,
5502 * because users of this 'device' dont need to change
5508 EXPORT_SYMBOL_GPL(init_dummy_netdev);
5512 * register_netdev - register a network device
5513 * @dev: device to register
5515 * Take a completed network device structure and add it to the kernel
5516 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5517 * chain. 0 is returned on success. A negative errno code is returned
5518 * on a failure to set up the device, or if the name is a duplicate.
5520 * This is a wrapper around register_netdevice that takes the rtnl semaphore
5521 * and expands the device name if you passed a format string to
5524 int register_netdev(struct net_device *dev)
5529 err = register_netdevice(dev);
5533 EXPORT_SYMBOL(register_netdev);
5535 int netdev_refcnt_read(const struct net_device *dev)
5539 for_each_possible_cpu(i)
5540 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5543 EXPORT_SYMBOL(netdev_refcnt_read);
5546 * netdev_wait_allrefs - wait until all references are gone.
5547 * @dev: target net_device
5549 * This is called when unregistering network devices.
5551 * Any protocol or device that holds a reference should register
5552 * for netdevice notification, and cleanup and put back the
5553 * reference if they receive an UNREGISTER event.
5554 * We can get stuck here if buggy protocols don't correctly
5557 static void netdev_wait_allrefs(struct net_device *dev)
5559 unsigned long rebroadcast_time, warning_time;
5562 linkwatch_forget_dev(dev);
5564 rebroadcast_time = warning_time = jiffies;
5565 refcnt = netdev_refcnt_read(dev);
5567 while (refcnt != 0) {
5568 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5571 /* Rebroadcast unregister notification */
5572 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5578 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
5579 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
5581 /* We must not have linkwatch events
5582 * pending on unregister. If this
5583 * happens, we simply run the queue
5584 * unscheduled, resulting in a noop
5587 linkwatch_run_queue();
5592 rebroadcast_time = jiffies;
5597 refcnt = netdev_refcnt_read(dev);
5599 if (time_after(jiffies, warning_time + 10 * HZ)) {
5600 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
5602 warning_time = jiffies;
5611 * register_netdevice(x1);
5612 * register_netdevice(x2);
5614 * unregister_netdevice(y1);
5615 * unregister_netdevice(y2);
5621 * We are invoked by rtnl_unlock().
5622 * This allows us to deal with problems:
5623 * 1) We can delete sysfs objects which invoke hotplug
5624 * without deadlocking with linkwatch via keventd.
5625 * 2) Since we run with the RTNL semaphore not held, we can sleep
5626 * safely in order to wait for the netdev refcnt to drop to zero.
5628 * We must not return until all unregister events added during
5629 * the interval the lock was held have been completed.
5631 void netdev_run_todo(void)
5633 struct list_head list;
5635 /* Snapshot list, allow later requests */
5636 list_replace_init(&net_todo_list, &list);
5641 /* Wait for rcu callbacks to finish before next phase */
5642 if (!list_empty(&list))
5645 while (!list_empty(&list)) {
5646 struct net_device *dev
5647 = list_first_entry(&list, struct net_device, todo_list);
5648 list_del(&dev->todo_list);
5651 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
5654 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
5655 pr_err("network todo '%s' but state %d\n",
5656 dev->name, dev->reg_state);
5661 dev->reg_state = NETREG_UNREGISTERED;
5663 on_each_cpu(flush_backlog, dev, 1);
5665 netdev_wait_allrefs(dev);
5668 BUG_ON(netdev_refcnt_read(dev));
5669 WARN_ON(rcu_access_pointer(dev->ip_ptr));
5670 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
5671 WARN_ON(dev->dn_ptr);
5673 if (dev->destructor)
5674 dev->destructor(dev);
5676 /* Free network device */
5677 kobject_put(&dev->dev.kobj);
5681 /* Convert net_device_stats to rtnl_link_stats64. They have the same
5682 * fields in the same order, with only the type differing.
5684 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
5685 const struct net_device_stats *netdev_stats)
5687 #if BITS_PER_LONG == 64
5688 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
5689 memcpy(stats64, netdev_stats, sizeof(*stats64));
5691 size_t i, n = sizeof(*stats64) / sizeof(u64);
5692 const unsigned long *src = (const unsigned long *)netdev_stats;
5693 u64 *dst = (u64 *)stats64;
5695 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
5696 sizeof(*stats64) / sizeof(u64));
5697 for (i = 0; i < n; i++)
5701 EXPORT_SYMBOL(netdev_stats_to_stats64);
5704 * dev_get_stats - get network device statistics
5705 * @dev: device to get statistics from
5706 * @storage: place to store stats
5708 * Get network statistics from device. Return @storage.
5709 * The device driver may provide its own method by setting
5710 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
5711 * otherwise the internal statistics structure is used.
5713 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
5714 struct rtnl_link_stats64 *storage)
5716 const struct net_device_ops *ops = dev->netdev_ops;
5718 if (ops->ndo_get_stats64) {
5719 memset(storage, 0, sizeof(*storage));
5720 ops->ndo_get_stats64(dev, storage);
5721 } else if (ops->ndo_get_stats) {
5722 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
5724 netdev_stats_to_stats64(storage, &dev->stats);
5726 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
5729 EXPORT_SYMBOL(dev_get_stats);
5731 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
5733 struct netdev_queue *queue = dev_ingress_queue(dev);
5735 #ifdef CONFIG_NET_CLS_ACT
5738 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
5741 netdev_init_one_queue(dev, queue, NULL);
5742 queue->qdisc = &noop_qdisc;
5743 queue->qdisc_sleeping = &noop_qdisc;
5744 rcu_assign_pointer(dev->ingress_queue, queue);
5749 static const struct ethtool_ops default_ethtool_ops;
5751 void netdev_set_default_ethtool_ops(struct net_device *dev,
5752 const struct ethtool_ops *ops)
5754 if (dev->ethtool_ops == &default_ethtool_ops)
5755 dev->ethtool_ops = ops;
5757 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
5760 * alloc_netdev_mqs - allocate network device
5761 * @sizeof_priv: size of private data to allocate space for
5762 * @name: device name format string
5763 * @setup: callback to initialize device
5764 * @txqs: the number of TX subqueues to allocate
5765 * @rxqs: the number of RX subqueues to allocate
5767 * Allocates a struct net_device with private data area for driver use
5768 * and performs basic initialization. Also allocates subquue structs
5769 * for each queue on the device.
5771 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
5772 void (*setup)(struct net_device *),
5773 unsigned int txqs, unsigned int rxqs)
5775 struct net_device *dev;
5777 struct net_device *p;
5779 BUG_ON(strlen(name) >= sizeof(dev->name));
5782 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
5788 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
5793 alloc_size = sizeof(struct net_device);
5795 /* ensure 32-byte alignment of private area */
5796 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
5797 alloc_size += sizeof_priv;
5799 /* ensure 32-byte alignment of whole construct */
5800 alloc_size += NETDEV_ALIGN - 1;
5802 p = kzalloc(alloc_size, GFP_KERNEL);
5806 dev = PTR_ALIGN(p, NETDEV_ALIGN);
5807 dev->padded = (char *)dev - (char *)p;
5809 dev->pcpu_refcnt = alloc_percpu(int);
5810 if (!dev->pcpu_refcnt)
5813 if (dev_addr_init(dev))
5819 dev_net_set(dev, &init_net);
5821 dev->gso_max_size = GSO_MAX_SIZE;
5822 dev->gso_max_segs = GSO_MAX_SEGS;
5824 INIT_LIST_HEAD(&dev->napi_list);
5825 INIT_LIST_HEAD(&dev->unreg_list);
5826 INIT_LIST_HEAD(&dev->link_watch_list);
5827 INIT_LIST_HEAD(&dev->upper_dev_list);
5828 dev->priv_flags = IFF_XMIT_DST_RELEASE;
5831 dev->num_tx_queues = txqs;
5832 dev->real_num_tx_queues = txqs;
5833 if (netif_alloc_netdev_queues(dev))
5837 dev->num_rx_queues = rxqs;
5838 dev->real_num_rx_queues = rxqs;
5839 if (netif_alloc_rx_queues(dev))
5843 strcpy(dev->name, name);
5844 dev->group = INIT_NETDEV_GROUP;
5845 if (!dev->ethtool_ops)
5846 dev->ethtool_ops = &default_ethtool_ops;
5854 free_percpu(dev->pcpu_refcnt);
5855 netif_free_tx_queues(dev);
5864 EXPORT_SYMBOL(alloc_netdev_mqs);
5867 * free_netdev - free network device
5870 * This function does the last stage of destroying an allocated device
5871 * interface. The reference to the device object is released.
5872 * If this is the last reference then it will be freed.
5874 void free_netdev(struct net_device *dev)
5876 struct napi_struct *p, *n;
5878 release_net(dev_net(dev));
5880 netif_free_tx_queues(dev);
5885 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
5887 /* Flush device addresses */
5888 dev_addr_flush(dev);
5890 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
5893 free_percpu(dev->pcpu_refcnt);
5894 dev->pcpu_refcnt = NULL;
5896 /* Compatibility with error handling in drivers */
5897 if (dev->reg_state == NETREG_UNINITIALIZED) {
5898 kfree((char *)dev - dev->padded);
5902 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
5903 dev->reg_state = NETREG_RELEASED;
5905 /* will free via device release */
5906 put_device(&dev->dev);
5908 EXPORT_SYMBOL(free_netdev);
5911 * synchronize_net - Synchronize with packet receive processing
5913 * Wait for packets currently being received to be done.
5914 * Does not block later packets from starting.
5916 void synchronize_net(void)
5919 if (rtnl_is_locked())
5920 synchronize_rcu_expedited();
5924 EXPORT_SYMBOL(synchronize_net);
5927 * unregister_netdevice_queue - remove device from the kernel
5931 * This function shuts down a device interface and removes it
5932 * from the kernel tables.
5933 * If head not NULL, device is queued to be unregistered later.
5935 * Callers must hold the rtnl semaphore. You may want
5936 * unregister_netdev() instead of this.
5939 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
5944 list_move_tail(&dev->unreg_list, head);
5946 rollback_registered(dev);
5947 /* Finish processing unregister after unlock */
5951 EXPORT_SYMBOL(unregister_netdevice_queue);
5954 * unregister_netdevice_many - unregister many devices
5955 * @head: list of devices
5957 void unregister_netdevice_many(struct list_head *head)
5959 struct net_device *dev;
5961 if (!list_empty(head)) {
5962 rollback_registered_many(head);
5963 list_for_each_entry(dev, head, unreg_list)
5967 EXPORT_SYMBOL(unregister_netdevice_many);
5970 * unregister_netdev - remove device from the kernel
5973 * This function shuts down a device interface and removes it
5974 * from the kernel tables.
5976 * This is just a wrapper for unregister_netdevice that takes
5977 * the rtnl semaphore. In general you want to use this and not
5978 * unregister_netdevice.
5980 void unregister_netdev(struct net_device *dev)
5983 unregister_netdevice(dev);
5986 EXPORT_SYMBOL(unregister_netdev);
5989 * dev_change_net_namespace - move device to different nethost namespace
5991 * @net: network namespace
5992 * @pat: If not NULL name pattern to try if the current device name
5993 * is already taken in the destination network namespace.
5995 * This function shuts down a device interface and moves it
5996 * to a new network namespace. On success 0 is returned, on
5997 * a failure a netagive errno code is returned.
5999 * Callers must hold the rtnl semaphore.
6002 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6008 /* Don't allow namespace local devices to be moved. */
6010 if (dev->features & NETIF_F_NETNS_LOCAL)
6013 /* Ensure the device has been registrered */
6014 if (dev->reg_state != NETREG_REGISTERED)
6017 /* Get out if there is nothing todo */
6019 if (net_eq(dev_net(dev), net))
6022 /* Pick the destination device name, and ensure
6023 * we can use it in the destination network namespace.
6026 if (__dev_get_by_name(net, dev->name)) {
6027 /* We get here if we can't use the current device name */
6030 if (dev_get_valid_name(net, dev, pat) < 0)
6035 * And now a mini version of register_netdevice unregister_netdevice.
6038 /* If device is running close it first. */
6041 /* And unlink it from device chain */
6043 unlist_netdevice(dev);
6047 /* Shutdown queueing discipline. */
6050 /* Notify protocols, that we are about to destroy
6051 this device. They should clean all the things.
6053 Note that dev->reg_state stays at NETREG_REGISTERED.
6054 This is wanted because this way 8021q and macvlan know
6055 the device is just moving and can keep their slaves up.
6057 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6059 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6060 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
6063 * Flush the unicast and multicast chains
6068 /* Send a netdev-removed uevent to the old namespace */
6069 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6071 /* Actually switch the network namespace */
6072 dev_net_set(dev, net);
6074 /* If there is an ifindex conflict assign a new one */
6075 if (__dev_get_by_index(net, dev->ifindex)) {
6076 int iflink = (dev->iflink == dev->ifindex);
6077 dev->ifindex = dev_new_index(net);
6079 dev->iflink = dev->ifindex;
6082 /* Send a netdev-add uevent to the new namespace */
6083 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6085 /* Fixup kobjects */
6086 err = device_rename(&dev->dev, dev->name);
6089 /* Add the device back in the hashes */
6090 list_netdevice(dev);
6092 /* Notify protocols, that a new device appeared. */
6093 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6096 * Prevent userspace races by waiting until the network
6097 * device is fully setup before sending notifications.
6099 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
6106 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6108 static int dev_cpu_callback(struct notifier_block *nfb,
6109 unsigned long action,
6112 struct sk_buff **list_skb;
6113 struct sk_buff *skb;
6114 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6115 struct softnet_data *sd, *oldsd;
6117 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6120 local_irq_disable();
6121 cpu = smp_processor_id();
6122 sd = &per_cpu(softnet_data, cpu);
6123 oldsd = &per_cpu(softnet_data, oldcpu);
6125 /* Find end of our completion_queue. */
6126 list_skb = &sd->completion_queue;
6128 list_skb = &(*list_skb)->next;
6129 /* Append completion queue from offline CPU. */
6130 *list_skb = oldsd->completion_queue;
6131 oldsd->completion_queue = NULL;
6133 /* Append output queue from offline CPU. */
6134 if (oldsd->output_queue) {
6135 *sd->output_queue_tailp = oldsd->output_queue;
6136 sd->output_queue_tailp = oldsd->output_queue_tailp;
6137 oldsd->output_queue = NULL;
6138 oldsd->output_queue_tailp = &oldsd->output_queue;
6140 /* Append NAPI poll list from offline CPU. */
6141 if (!list_empty(&oldsd->poll_list)) {
6142 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6143 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6146 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6149 /* Process offline CPU's input_pkt_queue */
6150 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6152 input_queue_head_incr(oldsd);
6154 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6156 input_queue_head_incr(oldsd);
6164 * netdev_increment_features - increment feature set by one
6165 * @all: current feature set
6166 * @one: new feature set
6167 * @mask: mask feature set
6169 * Computes a new feature set after adding a device with feature set
6170 * @one to the master device with current feature set @all. Will not
6171 * enable anything that is off in @mask. Returns the new feature set.
6173 netdev_features_t netdev_increment_features(netdev_features_t all,
6174 netdev_features_t one, netdev_features_t mask)
6176 if (mask & NETIF_F_GEN_CSUM)
6177 mask |= NETIF_F_ALL_CSUM;
6178 mask |= NETIF_F_VLAN_CHALLENGED;
6180 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6181 all &= one | ~NETIF_F_ALL_FOR_ALL;
6183 /* If one device supports hw checksumming, set for all. */
6184 if (all & NETIF_F_GEN_CSUM)
6185 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6189 EXPORT_SYMBOL(netdev_increment_features);
6191 static struct hlist_head * __net_init netdev_create_hash(void)
6194 struct hlist_head *hash;
6196 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6198 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6199 INIT_HLIST_HEAD(&hash[i]);
6204 /* Initialize per network namespace state */
6205 static int __net_init netdev_init(struct net *net)
6207 if (net != &init_net)
6208 INIT_LIST_HEAD(&net->dev_base_head);
6210 net->dev_name_head = netdev_create_hash();
6211 if (net->dev_name_head == NULL)
6214 net->dev_index_head = netdev_create_hash();
6215 if (net->dev_index_head == NULL)
6221 kfree(net->dev_name_head);
6227 * netdev_drivername - network driver for the device
6228 * @dev: network device
6230 * Determine network driver for device.
6232 const char *netdev_drivername(const struct net_device *dev)
6234 const struct device_driver *driver;
6235 const struct device *parent;
6236 const char *empty = "";
6238 parent = dev->dev.parent;
6242 driver = parent->driver;
6243 if (driver && driver->name)
6244 return driver->name;
6248 static int __netdev_printk(const char *level, const struct net_device *dev,
6249 struct va_format *vaf)
6253 if (dev && dev->dev.parent) {
6254 r = dev_printk_emit(level[1] - '0',
6257 dev_driver_string(dev->dev.parent),
6258 dev_name(dev->dev.parent),
6259 netdev_name(dev), vaf);
6261 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6263 r = printk("%s(NULL net_device): %pV", level, vaf);
6269 int netdev_printk(const char *level, const struct net_device *dev,
6270 const char *format, ...)
6272 struct va_format vaf;
6276 va_start(args, format);
6281 r = __netdev_printk(level, dev, &vaf);
6287 EXPORT_SYMBOL(netdev_printk);
6289 #define define_netdev_printk_level(func, level) \
6290 int func(const struct net_device *dev, const char *fmt, ...) \
6293 struct va_format vaf; \
6296 va_start(args, fmt); \
6301 r = __netdev_printk(level, dev, &vaf); \
6307 EXPORT_SYMBOL(func);
6309 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6310 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6311 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6312 define_netdev_printk_level(netdev_err, KERN_ERR);
6313 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6314 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6315 define_netdev_printk_level(netdev_info, KERN_INFO);
6317 static void __net_exit netdev_exit(struct net *net)
6319 kfree(net->dev_name_head);
6320 kfree(net->dev_index_head);
6323 static struct pernet_operations __net_initdata netdev_net_ops = {
6324 .init = netdev_init,
6325 .exit = netdev_exit,
6328 static void __net_exit default_device_exit(struct net *net)
6330 struct net_device *dev, *aux;
6332 * Push all migratable network devices back to the
6333 * initial network namespace
6336 for_each_netdev_safe(net, dev, aux) {
6338 char fb_name[IFNAMSIZ];
6340 /* Ignore unmoveable devices (i.e. loopback) */
6341 if (dev->features & NETIF_F_NETNS_LOCAL)
6344 /* Leave virtual devices for the generic cleanup */
6345 if (dev->rtnl_link_ops)
6348 /* Push remaining network devices to init_net */
6349 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6350 err = dev_change_net_namespace(dev, &init_net, fb_name);
6352 pr_emerg("%s: failed to move %s to init_net: %d\n",
6353 __func__, dev->name, err);
6360 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6362 /* At exit all network devices most be removed from a network
6363 * namespace. Do this in the reverse order of registration.
6364 * Do this across as many network namespaces as possible to
6365 * improve batching efficiency.
6367 struct net_device *dev;
6369 LIST_HEAD(dev_kill_list);
6372 list_for_each_entry(net, net_list, exit_list) {
6373 for_each_netdev_reverse(net, dev) {
6374 if (dev->rtnl_link_ops)
6375 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6377 unregister_netdevice_queue(dev, &dev_kill_list);
6380 unregister_netdevice_many(&dev_kill_list);
6381 list_del(&dev_kill_list);
6385 static struct pernet_operations __net_initdata default_device_ops = {
6386 .exit = default_device_exit,
6387 .exit_batch = default_device_exit_batch,
6391 * Initialize the DEV module. At boot time this walks the device list and
6392 * unhooks any devices that fail to initialise (normally hardware not
6393 * present) and leaves us with a valid list of present and active devices.
6398 * This is called single threaded during boot, so no need
6399 * to take the rtnl semaphore.
6401 static int __init net_dev_init(void)
6403 int i, rc = -ENOMEM;
6405 BUG_ON(!dev_boot_phase);
6407 if (dev_proc_init())
6410 if (netdev_kobject_init())
6413 INIT_LIST_HEAD(&ptype_all);
6414 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6415 INIT_LIST_HEAD(&ptype_base[i]);
6417 INIT_LIST_HEAD(&offload_base);
6419 if (register_pernet_subsys(&netdev_net_ops))
6423 * Initialise the packet receive queues.
6426 for_each_possible_cpu(i) {
6427 struct softnet_data *sd = &per_cpu(softnet_data, i);
6429 memset(sd, 0, sizeof(*sd));
6430 skb_queue_head_init(&sd->input_pkt_queue);
6431 skb_queue_head_init(&sd->process_queue);
6432 sd->completion_queue = NULL;
6433 INIT_LIST_HEAD(&sd->poll_list);
6434 sd->output_queue = NULL;
6435 sd->output_queue_tailp = &sd->output_queue;
6437 sd->csd.func = rps_trigger_softirq;
6443 sd->backlog.poll = process_backlog;
6444 sd->backlog.weight = weight_p;
6445 sd->backlog.gro_list = NULL;
6446 sd->backlog.gro_count = 0;
6448 #ifdef CONFIG_NET_FLOW_LIMIT
6449 sd->flow_limit = NULL;
6455 /* The loopback device is special if any other network devices
6456 * is present in a network namespace the loopback device must
6457 * be present. Since we now dynamically allocate and free the
6458 * loopback device ensure this invariant is maintained by
6459 * keeping the loopback device as the first device on the
6460 * list of network devices. Ensuring the loopback devices
6461 * is the first device that appears and the last network device
6464 if (register_pernet_device(&loopback_net_ops))
6467 if (register_pernet_device(&default_device_ops))
6470 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6471 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6473 hotcpu_notifier(dev_cpu_callback, 0);
6480 subsys_initcall(net_dev_init);