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>
134 #include <linux/if_macvlan.h>
136 #include "net-sysfs.h"
138 /* Instead of increasing this, you should create a hash table. */
139 #define MAX_GRO_SKBS 8
141 /* This should be increased if a protocol with a bigger head is added. */
142 #define GRO_MAX_HEAD (MAX_HEADER + 128)
144 static DEFINE_SPINLOCK(ptype_lock);
145 static DEFINE_SPINLOCK(offload_lock);
146 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
147 struct list_head ptype_all __read_mostly; /* Taps */
148 static struct list_head offload_base __read_mostly;
151 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
154 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
156 * Writers must hold the rtnl semaphore while they loop through the
157 * dev_base_head list, and hold dev_base_lock for writing when they do the
158 * actual updates. This allows pure readers to access the list even
159 * while a writer is preparing to update it.
161 * To put it another way, dev_base_lock is held for writing only to
162 * protect against pure readers; the rtnl semaphore provides the
163 * protection against other writers.
165 * See, for example usages, register_netdevice() and
166 * unregister_netdevice(), which must be called with the rtnl
169 DEFINE_RWLOCK(dev_base_lock);
170 EXPORT_SYMBOL(dev_base_lock);
172 /* protects napi_hash addition/deletion and napi_gen_id */
173 static DEFINE_SPINLOCK(napi_hash_lock);
175 static unsigned int napi_gen_id;
176 static DEFINE_HASHTABLE(napi_hash, 8);
178 static seqcount_t devnet_rename_seq;
180 static inline void dev_base_seq_inc(struct net *net)
182 while (++net->dev_base_seq == 0);
185 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
187 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
189 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
192 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
194 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
197 static inline void rps_lock(struct softnet_data *sd)
200 spin_lock(&sd->input_pkt_queue.lock);
204 static inline void rps_unlock(struct softnet_data *sd)
207 spin_unlock(&sd->input_pkt_queue.lock);
211 /* Device list insertion */
212 static void list_netdevice(struct net_device *dev)
214 struct net *net = dev_net(dev);
218 write_lock_bh(&dev_base_lock);
219 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
220 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
221 hlist_add_head_rcu(&dev->index_hlist,
222 dev_index_hash(net, dev->ifindex));
223 write_unlock_bh(&dev_base_lock);
225 dev_base_seq_inc(net);
228 /* Device list removal
229 * caller must respect a RCU grace period before freeing/reusing dev
231 static void unlist_netdevice(struct net_device *dev)
235 /* Unlink dev from the device chain */
236 write_lock_bh(&dev_base_lock);
237 list_del_rcu(&dev->dev_list);
238 hlist_del_rcu(&dev->name_hlist);
239 hlist_del_rcu(&dev->index_hlist);
240 write_unlock_bh(&dev_base_lock);
242 dev_base_seq_inc(dev_net(dev));
249 static RAW_NOTIFIER_HEAD(netdev_chain);
252 * Device drivers call our routines to queue packets here. We empty the
253 * queue in the local softnet handler.
256 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
257 EXPORT_PER_CPU_SYMBOL(softnet_data);
259 #ifdef CONFIG_LOCKDEP
261 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
262 * according to dev->type
264 static const unsigned short netdev_lock_type[] =
265 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
266 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
267 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
268 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
269 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
270 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
271 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
272 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
273 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
274 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
275 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
276 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
277 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
278 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
279 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
281 static const char *const netdev_lock_name[] =
282 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
283 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
284 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
285 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
286 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
287 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
288 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
289 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
290 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
291 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
292 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
293 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
294 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
295 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
296 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
298 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
299 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
301 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
305 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
306 if (netdev_lock_type[i] == dev_type)
308 /* the last key is used by default */
309 return ARRAY_SIZE(netdev_lock_type) - 1;
312 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
313 unsigned short dev_type)
317 i = netdev_lock_pos(dev_type);
318 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
319 netdev_lock_name[i]);
322 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
326 i = netdev_lock_pos(dev->type);
327 lockdep_set_class_and_name(&dev->addr_list_lock,
328 &netdev_addr_lock_key[i],
329 netdev_lock_name[i]);
332 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
333 unsigned short dev_type)
336 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
341 /*******************************************************************************
343 Protocol management and registration routines
345 *******************************************************************************/
348 * Add a protocol ID to the list. Now that the input handler is
349 * smarter we can dispense with all the messy stuff that used to be
352 * BEWARE!!! Protocol handlers, mangling input packets,
353 * MUST BE last in hash buckets and checking protocol handlers
354 * MUST start from promiscuous ptype_all chain in net_bh.
355 * It is true now, do not change it.
356 * Explanation follows: if protocol handler, mangling packet, will
357 * be the first on list, it is not able to sense, that packet
358 * is cloned and should be copied-on-write, so that it will
359 * change it and subsequent readers will get broken packet.
363 static inline struct list_head *ptype_head(const struct packet_type *pt)
365 if (pt->type == htons(ETH_P_ALL))
368 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
372 * dev_add_pack - add packet handler
373 * @pt: packet type declaration
375 * Add a protocol handler to the networking stack. The passed &packet_type
376 * is linked into kernel lists and may not be freed until it has been
377 * removed from the kernel lists.
379 * This call does not sleep therefore it can not
380 * guarantee all CPU's that are in middle of receiving packets
381 * will see the new packet type (until the next received packet).
384 void dev_add_pack(struct packet_type *pt)
386 struct list_head *head = ptype_head(pt);
388 spin_lock(&ptype_lock);
389 list_add_rcu(&pt->list, head);
390 spin_unlock(&ptype_lock);
392 EXPORT_SYMBOL(dev_add_pack);
395 * __dev_remove_pack - remove packet handler
396 * @pt: packet type declaration
398 * Remove a protocol handler that was previously added to the kernel
399 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
400 * from the kernel lists and can be freed or reused once this function
403 * The packet type might still be in use by receivers
404 * and must not be freed until after all the CPU's have gone
405 * through a quiescent state.
407 void __dev_remove_pack(struct packet_type *pt)
409 struct list_head *head = ptype_head(pt);
410 struct packet_type *pt1;
412 spin_lock(&ptype_lock);
414 list_for_each_entry(pt1, head, list) {
416 list_del_rcu(&pt->list);
421 pr_warn("dev_remove_pack: %p not found\n", pt);
423 spin_unlock(&ptype_lock);
425 EXPORT_SYMBOL(__dev_remove_pack);
428 * dev_remove_pack - remove packet handler
429 * @pt: packet type declaration
431 * Remove a protocol handler that was previously added to the kernel
432 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
433 * from the kernel lists and can be freed or reused once this function
436 * This call sleeps to guarantee that no CPU is looking at the packet
439 void dev_remove_pack(struct packet_type *pt)
441 __dev_remove_pack(pt);
445 EXPORT_SYMBOL(dev_remove_pack);
449 * dev_add_offload - register offload handlers
450 * @po: protocol offload declaration
452 * Add protocol offload handlers to the networking stack. The passed
453 * &proto_offload is linked into kernel lists and may not be freed until
454 * it has been removed from the kernel lists.
456 * This call does not sleep therefore it can not
457 * guarantee all CPU's that are in middle of receiving packets
458 * will see the new offload handlers (until the next received packet).
460 void dev_add_offload(struct packet_offload *po)
462 struct list_head *head = &offload_base;
464 spin_lock(&offload_lock);
465 list_add_rcu(&po->list, head);
466 spin_unlock(&offload_lock);
468 EXPORT_SYMBOL(dev_add_offload);
471 * __dev_remove_offload - remove offload handler
472 * @po: packet offload declaration
474 * Remove a protocol offload handler that was previously added to the
475 * kernel offload handlers by dev_add_offload(). The passed &offload_type
476 * is removed from the kernel lists and can be freed or reused once this
479 * The packet type might still be in use by receivers
480 * and must not be freed until after all the CPU's have gone
481 * through a quiescent state.
483 static void __dev_remove_offload(struct packet_offload *po)
485 struct list_head *head = &offload_base;
486 struct packet_offload *po1;
488 spin_lock(&offload_lock);
490 list_for_each_entry(po1, head, list) {
492 list_del_rcu(&po->list);
497 pr_warn("dev_remove_offload: %p not found\n", po);
499 spin_unlock(&offload_lock);
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, GFP_KERNEL);
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, GFP_KERNEL);
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, close_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, close_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->close_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;
1366 /* Remove the devices that don't need to be closed */
1367 list_for_each_entry_safe(dev, tmp, head, close_list)
1368 if (!(dev->flags & IFF_UP))
1369 list_del_init(&dev->close_list);
1371 __dev_close_many(head);
1373 list_for_each_entry_safe(dev, tmp, head, close_list) {
1374 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1375 call_netdevice_notifiers(NETDEV_DOWN, dev);
1376 list_del_init(&dev->close_list);
1383 * dev_close - shutdown an interface.
1384 * @dev: device to shutdown
1386 * This function moves an active device into down state. A
1387 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1388 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1391 int dev_close(struct net_device *dev)
1393 if (dev->flags & IFF_UP) {
1396 /* Block netpoll rx while the interface is going down */
1397 netpoll_rx_disable(dev);
1399 list_add(&dev->close_list, &single);
1400 dev_close_many(&single);
1403 netpoll_rx_enable(dev);
1407 EXPORT_SYMBOL(dev_close);
1411 * dev_disable_lro - disable Large Receive Offload on a device
1414 * Disable Large Receive Offload (LRO) on a net device. Must be
1415 * called under RTNL. This is needed if received packets may be
1416 * forwarded to another interface.
1418 void dev_disable_lro(struct net_device *dev)
1421 * If we're trying to disable lro on a vlan device
1422 * use the underlying physical device instead
1424 if (is_vlan_dev(dev))
1425 dev = vlan_dev_real_dev(dev);
1427 /* the same for macvlan devices */
1428 if (netif_is_macvlan(dev))
1429 dev = macvlan_dev_real_dev(dev);
1431 dev->wanted_features &= ~NETIF_F_LRO;
1432 netdev_update_features(dev);
1434 if (unlikely(dev->features & NETIF_F_LRO))
1435 netdev_WARN(dev, "failed to disable LRO!\n");
1437 EXPORT_SYMBOL(dev_disable_lro);
1439 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1440 struct net_device *dev)
1442 struct netdev_notifier_info info;
1444 netdev_notifier_info_init(&info, dev);
1445 return nb->notifier_call(nb, val, &info);
1448 static int dev_boot_phase = 1;
1451 * register_netdevice_notifier - register a network notifier block
1454 * Register a notifier to be called when network device events occur.
1455 * The notifier passed is linked into the kernel structures and must
1456 * not be reused until it has been unregistered. A negative errno code
1457 * is returned on a failure.
1459 * When registered all registration and up events are replayed
1460 * to the new notifier to allow device to have a race free
1461 * view of the network device list.
1464 int register_netdevice_notifier(struct notifier_block *nb)
1466 struct net_device *dev;
1467 struct net_device *last;
1472 err = raw_notifier_chain_register(&netdev_chain, nb);
1478 for_each_netdev(net, dev) {
1479 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1480 err = notifier_to_errno(err);
1484 if (!(dev->flags & IFF_UP))
1487 call_netdevice_notifier(nb, NETDEV_UP, dev);
1498 for_each_netdev(net, dev) {
1502 if (dev->flags & IFF_UP) {
1503 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1505 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1507 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1512 raw_notifier_chain_unregister(&netdev_chain, nb);
1515 EXPORT_SYMBOL(register_netdevice_notifier);
1518 * unregister_netdevice_notifier - unregister a network notifier block
1521 * Unregister a notifier previously registered by
1522 * register_netdevice_notifier(). The notifier is unlinked into the
1523 * kernel structures and may then be reused. A negative errno code
1524 * is returned on a failure.
1526 * After unregistering unregister and down device events are synthesized
1527 * for all devices on the device list to the removed notifier to remove
1528 * the need for special case cleanup code.
1531 int unregister_netdevice_notifier(struct notifier_block *nb)
1533 struct net_device *dev;
1538 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1543 for_each_netdev(net, dev) {
1544 if (dev->flags & IFF_UP) {
1545 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1547 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1549 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1556 EXPORT_SYMBOL(unregister_netdevice_notifier);
1559 * call_netdevice_notifiers_info - call all network notifier blocks
1560 * @val: value passed unmodified to notifier function
1561 * @dev: net_device pointer passed unmodified to notifier function
1562 * @info: notifier information data
1564 * Call all network notifier blocks. Parameters and return value
1565 * are as for raw_notifier_call_chain().
1568 static int call_netdevice_notifiers_info(unsigned long val,
1569 struct net_device *dev,
1570 struct netdev_notifier_info *info)
1573 netdev_notifier_info_init(info, dev);
1574 return raw_notifier_call_chain(&netdev_chain, val, info);
1578 * call_netdevice_notifiers - call all network notifier blocks
1579 * @val: value passed unmodified to notifier function
1580 * @dev: net_device pointer passed unmodified to notifier function
1582 * Call all network notifier blocks. Parameters and return value
1583 * are as for raw_notifier_call_chain().
1586 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1588 struct netdev_notifier_info info;
1590 return call_netdevice_notifiers_info(val, dev, &info);
1592 EXPORT_SYMBOL(call_netdevice_notifiers);
1594 static struct static_key netstamp_needed __read_mostly;
1595 #ifdef HAVE_JUMP_LABEL
1596 /* We are not allowed to call static_key_slow_dec() from irq context
1597 * If net_disable_timestamp() is called from irq context, defer the
1598 * static_key_slow_dec() calls.
1600 static atomic_t netstamp_needed_deferred;
1603 void net_enable_timestamp(void)
1605 #ifdef HAVE_JUMP_LABEL
1606 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1610 static_key_slow_dec(&netstamp_needed);
1614 static_key_slow_inc(&netstamp_needed);
1616 EXPORT_SYMBOL(net_enable_timestamp);
1618 void net_disable_timestamp(void)
1620 #ifdef HAVE_JUMP_LABEL
1621 if (in_interrupt()) {
1622 atomic_inc(&netstamp_needed_deferred);
1626 static_key_slow_dec(&netstamp_needed);
1628 EXPORT_SYMBOL(net_disable_timestamp);
1630 static inline void net_timestamp_set(struct sk_buff *skb)
1632 skb->tstamp.tv64 = 0;
1633 if (static_key_false(&netstamp_needed))
1634 __net_timestamp(skb);
1637 #define net_timestamp_check(COND, SKB) \
1638 if (static_key_false(&netstamp_needed)) { \
1639 if ((COND) && !(SKB)->tstamp.tv64) \
1640 __net_timestamp(SKB); \
1643 static inline bool is_skb_forwardable(struct net_device *dev,
1644 struct sk_buff *skb)
1648 if (!(dev->flags & IFF_UP))
1651 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1652 if (skb->len <= len)
1655 /* if TSO is enabled, we don't care about the length as the packet
1656 * could be forwarded without being segmented before
1658 if (skb_is_gso(skb))
1665 * dev_forward_skb - loopback an skb to another netif
1667 * @dev: destination network device
1668 * @skb: buffer to forward
1671 * NET_RX_SUCCESS (no congestion)
1672 * NET_RX_DROP (packet was dropped, but freed)
1674 * dev_forward_skb can be used for injecting an skb from the
1675 * start_xmit function of one device into the receive queue
1676 * of another device.
1678 * The receiving device may be in another namespace, so
1679 * we have to clear all information in the skb that could
1680 * impact namespace isolation.
1682 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1684 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1685 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1686 atomic_long_inc(&dev->rx_dropped);
1692 if (unlikely(!is_skb_forwardable(dev, skb))) {
1693 atomic_long_inc(&dev->rx_dropped);
1698 skb_scrub_packet(skb, true);
1699 skb->protocol = eth_type_trans(skb, dev);
1701 return netif_rx(skb);
1703 EXPORT_SYMBOL_GPL(dev_forward_skb);
1705 static inline int deliver_skb(struct sk_buff *skb,
1706 struct packet_type *pt_prev,
1707 struct net_device *orig_dev)
1709 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1711 atomic_inc(&skb->users);
1712 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1715 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1717 if (!ptype->af_packet_priv || !skb->sk)
1720 if (ptype->id_match)
1721 return ptype->id_match(ptype, skb->sk);
1722 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1729 * Support routine. Sends outgoing frames to any network
1730 * taps currently in use.
1733 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1735 struct packet_type *ptype;
1736 struct sk_buff *skb2 = NULL;
1737 struct packet_type *pt_prev = NULL;
1740 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1741 /* Never send packets back to the socket
1742 * they originated from - MvS (miquels@drinkel.ow.org)
1744 if ((ptype->dev == dev || !ptype->dev) &&
1745 (!skb_loop_sk(ptype, skb))) {
1747 deliver_skb(skb2, pt_prev, skb->dev);
1752 skb2 = skb_clone(skb, GFP_ATOMIC);
1756 net_timestamp_set(skb2);
1758 /* skb->nh should be correctly
1759 set by sender, so that the second statement is
1760 just protection against buggy protocols.
1762 skb_reset_mac_header(skb2);
1764 if (skb_network_header(skb2) < skb2->data ||
1765 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1766 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1767 ntohs(skb2->protocol),
1769 skb_reset_network_header(skb2);
1772 skb2->transport_header = skb2->network_header;
1773 skb2->pkt_type = PACKET_OUTGOING;
1778 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1783 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1784 * @dev: Network device
1785 * @txq: number of queues available
1787 * If real_num_tx_queues is changed the tc mappings may no longer be
1788 * valid. To resolve this verify the tc mapping remains valid and if
1789 * not NULL the mapping. With no priorities mapping to this
1790 * offset/count pair it will no longer be used. In the worst case TC0
1791 * is invalid nothing can be done so disable priority mappings. If is
1792 * expected that drivers will fix this mapping if they can before
1793 * calling netif_set_real_num_tx_queues.
1795 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1798 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1800 /* If TC0 is invalidated disable TC mapping */
1801 if (tc->offset + tc->count > txq) {
1802 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1807 /* Invalidated prio to tc mappings set to TC0 */
1808 for (i = 1; i < TC_BITMASK + 1; i++) {
1809 int q = netdev_get_prio_tc_map(dev, i);
1811 tc = &dev->tc_to_txq[q];
1812 if (tc->offset + tc->count > txq) {
1813 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1815 netdev_set_prio_tc_map(dev, i, 0);
1821 static DEFINE_MUTEX(xps_map_mutex);
1822 #define xmap_dereference(P) \
1823 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1825 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1828 struct xps_map *map = NULL;
1832 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1834 for (pos = 0; map && pos < map->len; pos++) {
1835 if (map->queues[pos] == index) {
1837 map->queues[pos] = map->queues[--map->len];
1839 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1840 kfree_rcu(map, rcu);
1850 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1852 struct xps_dev_maps *dev_maps;
1854 bool active = false;
1856 mutex_lock(&xps_map_mutex);
1857 dev_maps = xmap_dereference(dev->xps_maps);
1862 for_each_possible_cpu(cpu) {
1863 for (i = index; i < dev->num_tx_queues; i++) {
1864 if (!remove_xps_queue(dev_maps, cpu, i))
1867 if (i == dev->num_tx_queues)
1872 RCU_INIT_POINTER(dev->xps_maps, NULL);
1873 kfree_rcu(dev_maps, rcu);
1876 for (i = index; i < dev->num_tx_queues; i++)
1877 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1881 mutex_unlock(&xps_map_mutex);
1884 static struct xps_map *expand_xps_map(struct xps_map *map,
1887 struct xps_map *new_map;
1888 int alloc_len = XPS_MIN_MAP_ALLOC;
1891 for (pos = 0; map && pos < map->len; pos++) {
1892 if (map->queues[pos] != index)
1897 /* Need to add queue to this CPU's existing map */
1899 if (pos < map->alloc_len)
1902 alloc_len = map->alloc_len * 2;
1905 /* Need to allocate new map to store queue on this CPU's map */
1906 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1911 for (i = 0; i < pos; i++)
1912 new_map->queues[i] = map->queues[i];
1913 new_map->alloc_len = alloc_len;
1919 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
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 struct dev_kfree_skb_cb {
2148 enum skb_free_reason reason;
2151 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2153 return (struct dev_kfree_skb_cb *)skb->cb;
2156 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2158 unsigned long flags;
2160 if (likely(atomic_read(&skb->users) == 1)) {
2162 atomic_set(&skb->users, 0);
2163 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2166 get_kfree_skb_cb(skb)->reason = reason;
2167 local_irq_save(flags);
2168 skb->next = __this_cpu_read(softnet_data.completion_queue);
2169 __this_cpu_write(softnet_data.completion_queue, skb);
2170 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2171 local_irq_restore(flags);
2173 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2175 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2177 if (in_irq() || irqs_disabled())
2178 __dev_kfree_skb_irq(skb, reason);
2182 EXPORT_SYMBOL(__dev_kfree_skb_any);
2186 * netif_device_detach - mark device as removed
2187 * @dev: network device
2189 * Mark device as removed from system and therefore no longer available.
2191 void netif_device_detach(struct net_device *dev)
2193 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2194 netif_running(dev)) {
2195 netif_tx_stop_all_queues(dev);
2198 EXPORT_SYMBOL(netif_device_detach);
2201 * netif_device_attach - mark device as attached
2202 * @dev: network device
2204 * Mark device as attached from system and restart if needed.
2206 void netif_device_attach(struct net_device *dev)
2208 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2209 netif_running(dev)) {
2210 netif_tx_wake_all_queues(dev);
2211 __netdev_watchdog_up(dev);
2214 EXPORT_SYMBOL(netif_device_attach);
2216 static void skb_warn_bad_offload(const struct sk_buff *skb)
2218 static const netdev_features_t null_features = 0;
2219 struct net_device *dev = skb->dev;
2220 const char *driver = "";
2222 if (!net_ratelimit())
2225 if (dev && dev->dev.parent)
2226 driver = dev_driver_string(dev->dev.parent);
2228 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2229 "gso_type=%d ip_summed=%d\n",
2230 driver, dev ? &dev->features : &null_features,
2231 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2232 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2233 skb_shinfo(skb)->gso_type, skb->ip_summed);
2237 * Invalidate hardware checksum when packet is to be mangled, and
2238 * complete checksum manually on outgoing path.
2240 int skb_checksum_help(struct sk_buff *skb)
2243 int ret = 0, offset;
2245 if (skb->ip_summed == CHECKSUM_COMPLETE)
2246 goto out_set_summed;
2248 if (unlikely(skb_shinfo(skb)->gso_size)) {
2249 skb_warn_bad_offload(skb);
2253 /* Before computing a checksum, we should make sure no frag could
2254 * be modified by an external entity : checksum could be wrong.
2256 if (skb_has_shared_frag(skb)) {
2257 ret = __skb_linearize(skb);
2262 offset = skb_checksum_start_offset(skb);
2263 BUG_ON(offset >= skb_headlen(skb));
2264 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2266 offset += skb->csum_offset;
2267 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2269 if (skb_cloned(skb) &&
2270 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2271 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2276 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2278 skb->ip_summed = CHECKSUM_NONE;
2282 EXPORT_SYMBOL(skb_checksum_help);
2284 __be16 skb_network_protocol(struct sk_buff *skb)
2286 __be16 type = skb->protocol;
2287 int vlan_depth = ETH_HLEN;
2289 /* Tunnel gso handlers can set protocol to ethernet. */
2290 if (type == htons(ETH_P_TEB)) {
2293 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2296 eth = (struct ethhdr *)skb_mac_header(skb);
2297 type = eth->h_proto;
2300 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2301 struct vlan_hdr *vh;
2303 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2306 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2307 type = vh->h_vlan_encapsulated_proto;
2308 vlan_depth += VLAN_HLEN;
2315 * skb_mac_gso_segment - mac layer segmentation handler.
2316 * @skb: buffer to segment
2317 * @features: features for the output path (see dev->features)
2319 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2320 netdev_features_t features)
2322 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2323 struct packet_offload *ptype;
2324 __be16 type = skb_network_protocol(skb);
2326 if (unlikely(!type))
2327 return ERR_PTR(-EINVAL);
2329 __skb_pull(skb, skb->mac_len);
2332 list_for_each_entry_rcu(ptype, &offload_base, list) {
2333 if (ptype->type == type && ptype->callbacks.gso_segment) {
2334 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2337 err = ptype->callbacks.gso_send_check(skb);
2338 segs = ERR_PTR(err);
2339 if (err || skb_gso_ok(skb, features))
2341 __skb_push(skb, (skb->data -
2342 skb_network_header(skb)));
2344 segs = ptype->callbacks.gso_segment(skb, features);
2350 __skb_push(skb, skb->data - skb_mac_header(skb));
2354 EXPORT_SYMBOL(skb_mac_gso_segment);
2357 /* openvswitch calls this on rx path, so we need a different check.
2359 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2362 return skb->ip_summed != CHECKSUM_PARTIAL;
2364 return skb->ip_summed == CHECKSUM_NONE;
2368 * __skb_gso_segment - Perform segmentation on skb.
2369 * @skb: buffer to segment
2370 * @features: features for the output path (see dev->features)
2371 * @tx_path: whether it is called in TX path
2373 * This function segments the given skb and returns a list of segments.
2375 * It may return NULL if the skb requires no segmentation. This is
2376 * only possible when GSO is used for verifying header integrity.
2378 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2379 netdev_features_t features, bool tx_path)
2381 if (unlikely(skb_needs_check(skb, tx_path))) {
2384 skb_warn_bad_offload(skb);
2386 if (skb_header_cloned(skb) &&
2387 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2388 return ERR_PTR(err);
2391 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2392 SKB_GSO_CB(skb)->encap_level = 0;
2394 skb_reset_mac_header(skb);
2395 skb_reset_mac_len(skb);
2397 return skb_mac_gso_segment(skb, features);
2399 EXPORT_SYMBOL(__skb_gso_segment);
2401 /* Take action when hardware reception checksum errors are detected. */
2403 void netdev_rx_csum_fault(struct net_device *dev)
2405 if (net_ratelimit()) {
2406 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2410 EXPORT_SYMBOL(netdev_rx_csum_fault);
2413 /* Actually, we should eliminate this check as soon as we know, that:
2414 * 1. IOMMU is present and allows to map all the memory.
2415 * 2. No high memory really exists on this machine.
2418 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2420 #ifdef CONFIG_HIGHMEM
2422 if (!(dev->features & NETIF_F_HIGHDMA)) {
2423 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2424 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2425 if (PageHighMem(skb_frag_page(frag)))
2430 if (PCI_DMA_BUS_IS_PHYS) {
2431 struct device *pdev = dev->dev.parent;
2435 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2436 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2437 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2438 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2447 void (*destructor)(struct sk_buff *skb);
2450 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2452 static void dev_gso_skb_destructor(struct sk_buff *skb)
2454 struct dev_gso_cb *cb;
2456 kfree_skb_list(skb->next);
2459 cb = DEV_GSO_CB(skb);
2461 cb->destructor(skb);
2465 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2466 * @skb: buffer to segment
2467 * @features: device features as applicable to this skb
2469 * This function segments the given skb and stores the list of segments
2472 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2474 struct sk_buff *segs;
2476 segs = skb_gso_segment(skb, features);
2478 /* Verifying header integrity only. */
2483 return PTR_ERR(segs);
2486 DEV_GSO_CB(skb)->destructor = skb->destructor;
2487 skb->destructor = dev_gso_skb_destructor;
2492 static netdev_features_t harmonize_features(struct sk_buff *skb,
2493 netdev_features_t features)
2495 if (skb->ip_summed != CHECKSUM_NONE &&
2496 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2497 features &= ~NETIF_F_ALL_CSUM;
2498 } else if (illegal_highdma(skb->dev, skb)) {
2499 features &= ~NETIF_F_SG;
2505 netdev_features_t netif_skb_features(struct sk_buff *skb)
2507 __be16 protocol = skb->protocol;
2508 netdev_features_t features = skb->dev->features;
2510 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2511 features &= ~NETIF_F_GSO_MASK;
2513 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2514 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2515 protocol = veh->h_vlan_encapsulated_proto;
2516 } else if (!vlan_tx_tag_present(skb)) {
2517 return harmonize_features(skb, features);
2520 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2521 NETIF_F_HW_VLAN_STAG_TX);
2523 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2524 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2525 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2526 NETIF_F_HW_VLAN_STAG_TX;
2528 return harmonize_features(skb, features);
2530 EXPORT_SYMBOL(netif_skb_features);
2532 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2533 struct netdev_queue *txq, void *accel_priv)
2535 const struct net_device_ops *ops = dev->netdev_ops;
2536 int rc = NETDEV_TX_OK;
2537 unsigned int skb_len;
2539 if (likely(!skb->next)) {
2540 netdev_features_t features;
2543 * If device doesn't need skb->dst, release it right now while
2544 * its hot in this cpu cache
2546 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2549 features = netif_skb_features(skb);
2551 if (vlan_tx_tag_present(skb) &&
2552 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2553 skb = __vlan_put_tag(skb, skb->vlan_proto,
2554 vlan_tx_tag_get(skb));
2561 /* If encapsulation offload request, verify we are testing
2562 * hardware encapsulation features instead of standard
2563 * features for the netdev
2565 if (skb->encapsulation)
2566 features &= dev->hw_enc_features;
2568 if (netif_needs_gso(skb, features)) {
2569 if (unlikely(dev_gso_segment(skb, features)))
2574 if (skb_needs_linearize(skb, features) &&
2575 __skb_linearize(skb))
2578 /* If packet is not checksummed and device does not
2579 * support checksumming for this protocol, complete
2580 * checksumming here.
2582 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2583 if (skb->encapsulation)
2584 skb_set_inner_transport_header(skb,
2585 skb_checksum_start_offset(skb));
2587 skb_set_transport_header(skb,
2588 skb_checksum_start_offset(skb));
2589 if (!(features & NETIF_F_ALL_CSUM) &&
2590 skb_checksum_help(skb))
2595 if (!list_empty(&ptype_all))
2596 dev_queue_xmit_nit(skb, dev);
2600 rc = ops->ndo_dfwd_start_xmit(skb, dev, accel_priv);
2602 rc = ops->ndo_start_xmit(skb, dev);
2604 trace_net_dev_xmit(skb, rc, dev, skb_len);
2605 if (rc == NETDEV_TX_OK && txq)
2606 txq_trans_update(txq);
2612 struct sk_buff *nskb = skb->next;
2614 skb->next = nskb->next;
2617 if (!list_empty(&ptype_all))
2618 dev_queue_xmit_nit(nskb, dev);
2620 skb_len = nskb->len;
2622 rc = ops->ndo_dfwd_start_xmit(nskb, dev, accel_priv);
2624 rc = ops->ndo_start_xmit(nskb, dev);
2625 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2626 if (unlikely(rc != NETDEV_TX_OK)) {
2627 if (rc & ~NETDEV_TX_MASK)
2628 goto out_kfree_gso_skb;
2629 nskb->next = skb->next;
2633 txq_trans_update(txq);
2634 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2635 return NETDEV_TX_BUSY;
2636 } while (skb->next);
2639 if (likely(skb->next == NULL)) {
2640 skb->destructor = DEV_GSO_CB(skb)->destructor;
2649 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2651 static void qdisc_pkt_len_init(struct sk_buff *skb)
2653 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2655 qdisc_skb_cb(skb)->pkt_len = skb->len;
2657 /* To get more precise estimation of bytes sent on wire,
2658 * we add to pkt_len the headers size of all segments
2660 if (shinfo->gso_size) {
2661 unsigned int hdr_len;
2662 u16 gso_segs = shinfo->gso_segs;
2664 /* mac layer + network layer */
2665 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2667 /* + transport layer */
2668 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2669 hdr_len += tcp_hdrlen(skb);
2671 hdr_len += sizeof(struct udphdr);
2673 if (shinfo->gso_type & SKB_GSO_DODGY)
2674 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2677 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2681 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2682 struct net_device *dev,
2683 struct netdev_queue *txq)
2685 spinlock_t *root_lock = qdisc_lock(q);
2689 qdisc_pkt_len_init(skb);
2690 qdisc_calculate_pkt_len(skb, q);
2692 * Heuristic to force contended enqueues to serialize on a
2693 * separate lock before trying to get qdisc main lock.
2694 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2695 * and dequeue packets faster.
2697 contended = qdisc_is_running(q);
2698 if (unlikely(contended))
2699 spin_lock(&q->busylock);
2701 spin_lock(root_lock);
2702 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2705 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2706 qdisc_run_begin(q)) {
2708 * This is a work-conserving queue; there are no old skbs
2709 * waiting to be sent out; and the qdisc is not running -
2710 * xmit the skb directly.
2712 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2715 qdisc_bstats_update(q, skb);
2717 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2718 if (unlikely(contended)) {
2719 spin_unlock(&q->busylock);
2726 rc = NET_XMIT_SUCCESS;
2729 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2730 if (qdisc_run_begin(q)) {
2731 if (unlikely(contended)) {
2732 spin_unlock(&q->busylock);
2738 spin_unlock(root_lock);
2739 if (unlikely(contended))
2740 spin_unlock(&q->busylock);
2744 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2745 static void skb_update_prio(struct sk_buff *skb)
2747 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2749 if (!skb->priority && skb->sk && map) {
2750 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2752 if (prioidx < map->priomap_len)
2753 skb->priority = map->priomap[prioidx];
2757 #define skb_update_prio(skb)
2760 static DEFINE_PER_CPU(int, xmit_recursion);
2761 #define RECURSION_LIMIT 10
2764 * dev_loopback_xmit - loop back @skb
2765 * @skb: buffer to transmit
2767 int dev_loopback_xmit(struct sk_buff *skb)
2769 skb_reset_mac_header(skb);
2770 __skb_pull(skb, skb_network_offset(skb));
2771 skb->pkt_type = PACKET_LOOPBACK;
2772 skb->ip_summed = CHECKSUM_UNNECESSARY;
2773 WARN_ON(!skb_dst(skb));
2778 EXPORT_SYMBOL(dev_loopback_xmit);
2781 * dev_queue_xmit - transmit a buffer
2782 * @skb: buffer to transmit
2784 * Queue a buffer for transmission to a network device. The caller must
2785 * have set the device and priority and built the buffer before calling
2786 * this function. The function can be called from an interrupt.
2788 * A negative errno code is returned on a failure. A success does not
2789 * guarantee the frame will be transmitted as it may be dropped due
2790 * to congestion or traffic shaping.
2792 * -----------------------------------------------------------------------------------
2793 * I notice this method can also return errors from the queue disciplines,
2794 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2797 * Regardless of the return value, the skb is consumed, so it is currently
2798 * difficult to retry a send to this method. (You can bump the ref count
2799 * before sending to hold a reference for retry if you are careful.)
2801 * When calling this method, interrupts MUST be enabled. This is because
2802 * the BH enable code must have IRQs enabled so that it will not deadlock.
2805 int dev_queue_xmit(struct sk_buff *skb)
2807 struct net_device *dev = skb->dev;
2808 struct netdev_queue *txq;
2812 skb_reset_mac_header(skb);
2814 /* Disable soft irqs for various locks below. Also
2815 * stops preemption for RCU.
2819 skb_update_prio(skb);
2821 txq = netdev_pick_tx(dev, skb);
2822 q = rcu_dereference_bh(txq->qdisc);
2824 #ifdef CONFIG_NET_CLS_ACT
2825 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2827 trace_net_dev_queue(skb);
2829 rc = __dev_xmit_skb(skb, q, dev, txq);
2833 /* The device has no queue. Common case for software devices:
2834 loopback, all the sorts of tunnels...
2836 Really, it is unlikely that netif_tx_lock protection is necessary
2837 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2839 However, it is possible, that they rely on protection
2842 Check this and shot the lock. It is not prone from deadlocks.
2843 Either shot noqueue qdisc, it is even simpler 8)
2845 if (dev->flags & IFF_UP) {
2846 int cpu = smp_processor_id(); /* ok because BHs are off */
2848 if (txq->xmit_lock_owner != cpu) {
2850 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2851 goto recursion_alert;
2853 HARD_TX_LOCK(dev, txq, cpu);
2855 if (!netif_xmit_stopped(txq)) {
2856 __this_cpu_inc(xmit_recursion);
2857 rc = dev_hard_start_xmit(skb, dev, txq, NULL);
2858 __this_cpu_dec(xmit_recursion);
2859 if (dev_xmit_complete(rc)) {
2860 HARD_TX_UNLOCK(dev, txq);
2864 HARD_TX_UNLOCK(dev, txq);
2865 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2868 /* Recursion is detected! It is possible,
2872 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2878 rcu_read_unlock_bh();
2883 rcu_read_unlock_bh();
2886 EXPORT_SYMBOL(dev_queue_xmit);
2889 /*=======================================================================
2891 =======================================================================*/
2893 int netdev_max_backlog __read_mostly = 1000;
2894 EXPORT_SYMBOL(netdev_max_backlog);
2896 int netdev_tstamp_prequeue __read_mostly = 1;
2897 int netdev_budget __read_mostly = 300;
2898 int weight_p __read_mostly = 64; /* old backlog weight */
2900 /* Called with irq disabled */
2901 static inline void ____napi_schedule(struct softnet_data *sd,
2902 struct napi_struct *napi)
2904 list_add_tail(&napi->poll_list, &sd->poll_list);
2905 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2910 /* One global table that all flow-based protocols share. */
2911 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2912 EXPORT_SYMBOL(rps_sock_flow_table);
2914 struct static_key rps_needed __read_mostly;
2916 static struct rps_dev_flow *
2917 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2918 struct rps_dev_flow *rflow, u16 next_cpu)
2920 if (next_cpu != RPS_NO_CPU) {
2921 #ifdef CONFIG_RFS_ACCEL
2922 struct netdev_rx_queue *rxqueue;
2923 struct rps_dev_flow_table *flow_table;
2924 struct rps_dev_flow *old_rflow;
2929 /* Should we steer this flow to a different hardware queue? */
2930 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2931 !(dev->features & NETIF_F_NTUPLE))
2933 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2934 if (rxq_index == skb_get_rx_queue(skb))
2937 rxqueue = dev->_rx + rxq_index;
2938 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2941 flow_id = skb->rxhash & flow_table->mask;
2942 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2943 rxq_index, flow_id);
2947 rflow = &flow_table->flows[flow_id];
2949 if (old_rflow->filter == rflow->filter)
2950 old_rflow->filter = RPS_NO_FILTER;
2954 per_cpu(softnet_data, next_cpu).input_queue_head;
2957 rflow->cpu = next_cpu;
2962 * get_rps_cpu is called from netif_receive_skb and returns the target
2963 * CPU from the RPS map of the receiving queue for a given skb.
2964 * rcu_read_lock must be held on entry.
2966 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2967 struct rps_dev_flow **rflowp)
2969 struct netdev_rx_queue *rxqueue;
2970 struct rps_map *map;
2971 struct rps_dev_flow_table *flow_table;
2972 struct rps_sock_flow_table *sock_flow_table;
2976 if (skb_rx_queue_recorded(skb)) {
2977 u16 index = skb_get_rx_queue(skb);
2978 if (unlikely(index >= dev->real_num_rx_queues)) {
2979 WARN_ONCE(dev->real_num_rx_queues > 1,
2980 "%s received packet on queue %u, but number "
2981 "of RX queues is %u\n",
2982 dev->name, index, dev->real_num_rx_queues);
2985 rxqueue = dev->_rx + index;
2989 map = rcu_dereference(rxqueue->rps_map);
2991 if (map->len == 1 &&
2992 !rcu_access_pointer(rxqueue->rps_flow_table)) {
2993 tcpu = map->cpus[0];
2994 if (cpu_online(tcpu))
2998 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3002 skb_reset_network_header(skb);
3003 if (!skb_get_hash(skb))
3006 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3007 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3008 if (flow_table && sock_flow_table) {
3010 struct rps_dev_flow *rflow;
3012 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3015 next_cpu = sock_flow_table->ents[skb->rxhash &
3016 sock_flow_table->mask];
3019 * If the desired CPU (where last recvmsg was done) is
3020 * different from current CPU (one in the rx-queue flow
3021 * table entry), switch if one of the following holds:
3022 * - Current CPU is unset (equal to RPS_NO_CPU).
3023 * - Current CPU is offline.
3024 * - The current CPU's queue tail has advanced beyond the
3025 * last packet that was enqueued using this table entry.
3026 * This guarantees that all previous packets for the flow
3027 * have been dequeued, thus preserving in order delivery.
3029 if (unlikely(tcpu != next_cpu) &&
3030 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3031 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3032 rflow->last_qtail)) >= 0)) {
3034 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3037 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3045 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3047 if (cpu_online(tcpu)) {
3057 #ifdef CONFIG_RFS_ACCEL
3060 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3061 * @dev: Device on which the filter was set
3062 * @rxq_index: RX queue index
3063 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3064 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3066 * Drivers that implement ndo_rx_flow_steer() should periodically call
3067 * this function for each installed filter and remove the filters for
3068 * which it returns %true.
3070 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3071 u32 flow_id, u16 filter_id)
3073 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3074 struct rps_dev_flow_table *flow_table;
3075 struct rps_dev_flow *rflow;
3080 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3081 if (flow_table && flow_id <= flow_table->mask) {
3082 rflow = &flow_table->flows[flow_id];
3083 cpu = ACCESS_ONCE(rflow->cpu);
3084 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3085 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3086 rflow->last_qtail) <
3087 (int)(10 * flow_table->mask)))
3093 EXPORT_SYMBOL(rps_may_expire_flow);
3095 #endif /* CONFIG_RFS_ACCEL */
3097 /* Called from hardirq (IPI) context */
3098 static void rps_trigger_softirq(void *data)
3100 struct softnet_data *sd = data;
3102 ____napi_schedule(sd, &sd->backlog);
3106 #endif /* CONFIG_RPS */
3109 * Check if this softnet_data structure is another cpu one
3110 * If yes, queue it to our IPI list and return 1
3113 static int rps_ipi_queued(struct softnet_data *sd)
3116 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3119 sd->rps_ipi_next = mysd->rps_ipi_list;
3120 mysd->rps_ipi_list = sd;
3122 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3125 #endif /* CONFIG_RPS */
3129 #ifdef CONFIG_NET_FLOW_LIMIT
3130 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3133 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3135 #ifdef CONFIG_NET_FLOW_LIMIT
3136 struct sd_flow_limit *fl;
3137 struct softnet_data *sd;
3138 unsigned int old_flow, new_flow;
3140 if (qlen < (netdev_max_backlog >> 1))
3143 sd = &__get_cpu_var(softnet_data);
3146 fl = rcu_dereference(sd->flow_limit);
3148 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3149 old_flow = fl->history[fl->history_head];
3150 fl->history[fl->history_head] = new_flow;
3153 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3155 if (likely(fl->buckets[old_flow]))
3156 fl->buckets[old_flow]--;
3158 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3170 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3171 * queue (may be a remote CPU queue).
3173 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3174 unsigned int *qtail)
3176 struct softnet_data *sd;
3177 unsigned long flags;
3180 sd = &per_cpu(softnet_data, cpu);
3182 local_irq_save(flags);
3185 qlen = skb_queue_len(&sd->input_pkt_queue);
3186 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3187 if (skb_queue_len(&sd->input_pkt_queue)) {
3189 __skb_queue_tail(&sd->input_pkt_queue, skb);
3190 input_queue_tail_incr_save(sd, qtail);
3192 local_irq_restore(flags);
3193 return NET_RX_SUCCESS;
3196 /* Schedule NAPI for backlog device
3197 * We can use non atomic operation since we own the queue lock
3199 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3200 if (!rps_ipi_queued(sd))
3201 ____napi_schedule(sd, &sd->backlog);
3209 local_irq_restore(flags);
3211 atomic_long_inc(&skb->dev->rx_dropped);
3217 * netif_rx - post buffer to the network code
3218 * @skb: buffer to post
3220 * This function receives a packet from a device driver and queues it for
3221 * the upper (protocol) levels to process. It always succeeds. The buffer
3222 * may be dropped during processing for congestion control or by the
3226 * NET_RX_SUCCESS (no congestion)
3227 * NET_RX_DROP (packet was dropped)
3231 int netif_rx(struct sk_buff *skb)
3235 /* if netpoll wants it, pretend we never saw it */
3236 if (netpoll_rx(skb))
3239 net_timestamp_check(netdev_tstamp_prequeue, skb);
3241 trace_netif_rx(skb);
3243 if (static_key_false(&rps_needed)) {
3244 struct rps_dev_flow voidflow, *rflow = &voidflow;
3250 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3252 cpu = smp_processor_id();
3254 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3262 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3267 EXPORT_SYMBOL(netif_rx);
3269 int netif_rx_ni(struct sk_buff *skb)
3274 err = netif_rx(skb);
3275 if (local_softirq_pending())
3281 EXPORT_SYMBOL(netif_rx_ni);
3283 static void net_tx_action(struct softirq_action *h)
3285 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3287 if (sd->completion_queue) {
3288 struct sk_buff *clist;
3290 local_irq_disable();
3291 clist = sd->completion_queue;
3292 sd->completion_queue = NULL;
3296 struct sk_buff *skb = clist;
3297 clist = clist->next;
3299 WARN_ON(atomic_read(&skb->users));
3300 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3301 trace_consume_skb(skb);
3303 trace_kfree_skb(skb, net_tx_action);
3308 if (sd->output_queue) {
3311 local_irq_disable();
3312 head = sd->output_queue;
3313 sd->output_queue = NULL;
3314 sd->output_queue_tailp = &sd->output_queue;
3318 struct Qdisc *q = head;
3319 spinlock_t *root_lock;
3321 head = head->next_sched;
3323 root_lock = qdisc_lock(q);
3324 if (spin_trylock(root_lock)) {
3325 smp_mb__before_clear_bit();
3326 clear_bit(__QDISC_STATE_SCHED,
3329 spin_unlock(root_lock);
3331 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3333 __netif_reschedule(q);
3335 smp_mb__before_clear_bit();
3336 clear_bit(__QDISC_STATE_SCHED,
3344 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3345 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3346 /* This hook is defined here for ATM LANE */
3347 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3348 unsigned char *addr) __read_mostly;
3349 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3352 #ifdef CONFIG_NET_CLS_ACT
3353 /* TODO: Maybe we should just force sch_ingress to be compiled in
3354 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3355 * a compare and 2 stores extra right now if we dont have it on
3356 * but have CONFIG_NET_CLS_ACT
3357 * NOTE: This doesn't stop any functionality; if you dont have
3358 * the ingress scheduler, you just can't add policies on ingress.
3361 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3363 struct net_device *dev = skb->dev;
3364 u32 ttl = G_TC_RTTL(skb->tc_verd);
3365 int result = TC_ACT_OK;
3368 if (unlikely(MAX_RED_LOOP < ttl++)) {
3369 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3370 skb->skb_iif, dev->ifindex);
3374 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3375 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3378 if (q != &noop_qdisc) {
3379 spin_lock(qdisc_lock(q));
3380 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3381 result = qdisc_enqueue_root(skb, q);
3382 spin_unlock(qdisc_lock(q));
3388 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3389 struct packet_type **pt_prev,
3390 int *ret, struct net_device *orig_dev)
3392 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3394 if (!rxq || rxq->qdisc == &noop_qdisc)
3398 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3402 switch (ing_filter(skb, rxq)) {
3416 * netdev_rx_handler_register - register receive handler
3417 * @dev: device to register a handler for
3418 * @rx_handler: receive handler to register
3419 * @rx_handler_data: data pointer that is used by rx handler
3421 * Register a receive hander for a device. This handler will then be
3422 * called from __netif_receive_skb. A negative errno code is returned
3425 * The caller must hold the rtnl_mutex.
3427 * For a general description of rx_handler, see enum rx_handler_result.
3429 int netdev_rx_handler_register(struct net_device *dev,
3430 rx_handler_func_t *rx_handler,
3431 void *rx_handler_data)
3435 if (dev->rx_handler)
3438 /* Note: rx_handler_data must be set before rx_handler */
3439 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3440 rcu_assign_pointer(dev->rx_handler, rx_handler);
3444 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3447 * netdev_rx_handler_unregister - unregister receive handler
3448 * @dev: device to unregister a handler from
3450 * Unregister a receive handler from a device.
3452 * The caller must hold the rtnl_mutex.
3454 void netdev_rx_handler_unregister(struct net_device *dev)
3458 RCU_INIT_POINTER(dev->rx_handler, NULL);
3459 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3460 * section has a guarantee to see a non NULL rx_handler_data
3464 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3466 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3469 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3470 * the special handling of PFMEMALLOC skbs.
3472 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3474 switch (skb->protocol) {
3475 case __constant_htons(ETH_P_ARP):
3476 case __constant_htons(ETH_P_IP):
3477 case __constant_htons(ETH_P_IPV6):
3478 case __constant_htons(ETH_P_8021Q):
3479 case __constant_htons(ETH_P_8021AD):
3486 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3488 struct packet_type *ptype, *pt_prev;
3489 rx_handler_func_t *rx_handler;
3490 struct net_device *orig_dev;
3491 struct net_device *null_or_dev;
3492 bool deliver_exact = false;
3493 int ret = NET_RX_DROP;
3496 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3498 trace_netif_receive_skb(skb);
3500 /* if we've gotten here through NAPI, check netpoll */
3501 if (netpoll_receive_skb(skb))
3504 orig_dev = skb->dev;
3506 skb_reset_network_header(skb);
3507 if (!skb_transport_header_was_set(skb))
3508 skb_reset_transport_header(skb);
3509 skb_reset_mac_len(skb);
3516 skb->skb_iif = skb->dev->ifindex;
3518 __this_cpu_inc(softnet_data.processed);
3520 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3521 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3522 skb = vlan_untag(skb);
3527 #ifdef CONFIG_NET_CLS_ACT
3528 if (skb->tc_verd & TC_NCLS) {
3529 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3537 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3538 if (!ptype->dev || ptype->dev == skb->dev) {
3540 ret = deliver_skb(skb, pt_prev, orig_dev);
3546 #ifdef CONFIG_NET_CLS_ACT
3547 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3553 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3556 if (vlan_tx_tag_present(skb)) {
3558 ret = deliver_skb(skb, pt_prev, orig_dev);
3561 if (vlan_do_receive(&skb))
3563 else if (unlikely(!skb))
3567 rx_handler = rcu_dereference(skb->dev->rx_handler);
3570 ret = deliver_skb(skb, pt_prev, orig_dev);
3573 switch (rx_handler(&skb)) {
3574 case RX_HANDLER_CONSUMED:
3575 ret = NET_RX_SUCCESS;
3577 case RX_HANDLER_ANOTHER:
3579 case RX_HANDLER_EXACT:
3580 deliver_exact = true;
3581 case RX_HANDLER_PASS:
3588 if (unlikely(vlan_tx_tag_present(skb))) {
3589 if (vlan_tx_tag_get_id(skb))
3590 skb->pkt_type = PACKET_OTHERHOST;
3591 /* Note: we might in the future use prio bits
3592 * and set skb->priority like in vlan_do_receive()
3593 * For the time being, just ignore Priority Code Point
3598 /* deliver only exact match when indicated */
3599 null_or_dev = deliver_exact ? skb->dev : NULL;
3601 type = skb->protocol;
3602 list_for_each_entry_rcu(ptype,
3603 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3604 if (ptype->type == type &&
3605 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3606 ptype->dev == orig_dev)) {
3608 ret = deliver_skb(skb, pt_prev, orig_dev);
3614 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3617 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3620 atomic_long_inc(&skb->dev->rx_dropped);
3622 /* Jamal, now you will not able to escape explaining
3623 * me how you were going to use this. :-)
3634 static int __netif_receive_skb(struct sk_buff *skb)
3638 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3639 unsigned long pflags = current->flags;
3642 * PFMEMALLOC skbs are special, they should
3643 * - be delivered to SOCK_MEMALLOC sockets only
3644 * - stay away from userspace
3645 * - have bounded memory usage
3647 * Use PF_MEMALLOC as this saves us from propagating the allocation
3648 * context down to all allocation sites.
3650 current->flags |= PF_MEMALLOC;
3651 ret = __netif_receive_skb_core(skb, true);
3652 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3654 ret = __netif_receive_skb_core(skb, false);
3660 * netif_receive_skb - process receive buffer from network
3661 * @skb: buffer to process
3663 * netif_receive_skb() is the main receive data processing function.
3664 * It always succeeds. The buffer may be dropped during processing
3665 * for congestion control or by the protocol layers.
3667 * This function may only be called from softirq context and interrupts
3668 * should be enabled.
3670 * Return values (usually ignored):
3671 * NET_RX_SUCCESS: no congestion
3672 * NET_RX_DROP: packet was dropped
3674 int netif_receive_skb(struct sk_buff *skb)
3676 net_timestamp_check(netdev_tstamp_prequeue, skb);
3678 if (skb_defer_rx_timestamp(skb))
3679 return NET_RX_SUCCESS;
3682 if (static_key_false(&rps_needed)) {
3683 struct rps_dev_flow voidflow, *rflow = &voidflow;
3688 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3691 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3698 return __netif_receive_skb(skb);
3700 EXPORT_SYMBOL(netif_receive_skb);
3702 /* Network device is going away, flush any packets still pending
3703 * Called with irqs disabled.
3705 static void flush_backlog(void *arg)
3707 struct net_device *dev = arg;
3708 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3709 struct sk_buff *skb, *tmp;
3712 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3713 if (skb->dev == dev) {
3714 __skb_unlink(skb, &sd->input_pkt_queue);
3716 input_queue_head_incr(sd);
3721 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3722 if (skb->dev == dev) {
3723 __skb_unlink(skb, &sd->process_queue);
3725 input_queue_head_incr(sd);
3730 static int napi_gro_complete(struct sk_buff *skb)
3732 struct packet_offload *ptype;
3733 __be16 type = skb->protocol;
3734 struct list_head *head = &offload_base;
3737 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3739 if (NAPI_GRO_CB(skb)->count == 1) {
3740 skb_shinfo(skb)->gso_size = 0;
3745 list_for_each_entry_rcu(ptype, head, list) {
3746 if (ptype->type != type || !ptype->callbacks.gro_complete)
3749 err = ptype->callbacks.gro_complete(skb, 0);
3755 WARN_ON(&ptype->list == head);
3757 return NET_RX_SUCCESS;
3761 return netif_receive_skb(skb);
3764 /* napi->gro_list contains packets ordered by age.
3765 * youngest packets at the head of it.
3766 * Complete skbs in reverse order to reduce latencies.
3768 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3770 struct sk_buff *skb, *prev = NULL;
3772 /* scan list and build reverse chain */
3773 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3778 for (skb = prev; skb; skb = prev) {
3781 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3785 napi_gro_complete(skb);
3789 napi->gro_list = NULL;
3791 EXPORT_SYMBOL(napi_gro_flush);
3793 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3796 unsigned int maclen = skb->dev->hard_header_len;
3798 for (p = napi->gro_list; p; p = p->next) {
3799 unsigned long diffs;
3801 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3802 diffs |= p->vlan_tci ^ skb->vlan_tci;
3803 if (maclen == ETH_HLEN)
3804 diffs |= compare_ether_header(skb_mac_header(p),
3805 skb_gro_mac_header(skb));
3807 diffs = memcmp(skb_mac_header(p),
3808 skb_gro_mac_header(skb),
3810 NAPI_GRO_CB(p)->same_flow = !diffs;
3811 NAPI_GRO_CB(p)->flush = 0;
3815 static void skb_gro_reset_offset(struct sk_buff *skb)
3817 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3818 const skb_frag_t *frag0 = &pinfo->frags[0];
3820 NAPI_GRO_CB(skb)->data_offset = 0;
3821 NAPI_GRO_CB(skb)->frag0 = NULL;
3822 NAPI_GRO_CB(skb)->frag0_len = 0;
3824 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3826 !PageHighMem(skb_frag_page(frag0))) {
3827 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3828 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3832 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3834 struct sk_buff **pp = NULL;
3835 struct packet_offload *ptype;
3836 __be16 type = skb->protocol;
3837 struct list_head *head = &offload_base;
3839 enum gro_result ret;
3841 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3844 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3847 skb_gro_reset_offset(skb);
3848 gro_list_prepare(napi, skb);
3851 list_for_each_entry_rcu(ptype, head, list) {
3852 if (ptype->type != type || !ptype->callbacks.gro_receive)
3855 skb_set_network_header(skb, skb_gro_offset(skb));
3856 skb_reset_mac_len(skb);
3857 NAPI_GRO_CB(skb)->same_flow = 0;
3858 NAPI_GRO_CB(skb)->flush = 0;
3859 NAPI_GRO_CB(skb)->free = 0;
3861 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3866 if (&ptype->list == head)
3869 same_flow = NAPI_GRO_CB(skb)->same_flow;
3870 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3873 struct sk_buff *nskb = *pp;
3877 napi_gro_complete(nskb);
3884 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3888 NAPI_GRO_CB(skb)->count = 1;
3889 NAPI_GRO_CB(skb)->age = jiffies;
3890 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3891 skb->next = napi->gro_list;
3892 napi->gro_list = skb;
3896 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3897 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3899 BUG_ON(skb->end - skb->tail < grow);
3901 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3904 skb->data_len -= grow;
3906 skb_shinfo(skb)->frags[0].page_offset += grow;
3907 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3909 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3910 skb_frag_unref(skb, 0);
3911 memmove(skb_shinfo(skb)->frags,
3912 skb_shinfo(skb)->frags + 1,
3913 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3926 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3930 if (netif_receive_skb(skb))
3938 case GRO_MERGED_FREE:
3939 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
3940 kmem_cache_free(skbuff_head_cache, skb);
3953 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3955 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
3957 EXPORT_SYMBOL(napi_gro_receive);
3959 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
3961 __skb_pull(skb, skb_headlen(skb));
3962 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
3963 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
3965 skb->dev = napi->dev;
3971 struct sk_buff *napi_get_frags(struct napi_struct *napi)
3973 struct sk_buff *skb = napi->skb;
3976 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
3981 EXPORT_SYMBOL(napi_get_frags);
3983 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
3988 if (netif_receive_skb(skb))
3993 case GRO_MERGED_FREE:
3994 napi_reuse_skb(napi, skb);
4005 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4007 struct sk_buff *skb = napi->skb;
4011 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4012 napi_reuse_skb(napi, skb);
4015 skb->protocol = eth_type_trans(skb, skb->dev);
4020 gro_result_t napi_gro_frags(struct napi_struct *napi)
4022 struct sk_buff *skb = napi_frags_skb(napi);
4027 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4029 EXPORT_SYMBOL(napi_gro_frags);
4032 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4033 * Note: called with local irq disabled, but exits with local irq enabled.
4035 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4038 struct softnet_data *remsd = sd->rps_ipi_list;
4041 sd->rps_ipi_list = NULL;
4045 /* Send pending IPI's to kick RPS processing on remote cpus. */
4047 struct softnet_data *next = remsd->rps_ipi_next;
4049 if (cpu_online(remsd->cpu))
4050 __smp_call_function_single(remsd->cpu,
4059 static int process_backlog(struct napi_struct *napi, int quota)
4062 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4065 /* Check if we have pending ipi, its better to send them now,
4066 * not waiting net_rx_action() end.
4068 if (sd->rps_ipi_list) {
4069 local_irq_disable();
4070 net_rps_action_and_irq_enable(sd);
4073 napi->weight = weight_p;
4074 local_irq_disable();
4075 while (work < quota) {
4076 struct sk_buff *skb;
4079 while ((skb = __skb_dequeue(&sd->process_queue))) {
4081 __netif_receive_skb(skb);
4082 local_irq_disable();
4083 input_queue_head_incr(sd);
4084 if (++work >= quota) {
4091 qlen = skb_queue_len(&sd->input_pkt_queue);
4093 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4094 &sd->process_queue);
4096 if (qlen < quota - work) {
4098 * Inline a custom version of __napi_complete().
4099 * only current cpu owns and manipulates this napi,
4100 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4101 * we can use a plain write instead of clear_bit(),
4102 * and we dont need an smp_mb() memory barrier.
4104 list_del(&napi->poll_list);
4107 quota = work + qlen;
4117 * __napi_schedule - schedule for receive
4118 * @n: entry to schedule
4120 * The entry's receive function will be scheduled to run
4122 void __napi_schedule(struct napi_struct *n)
4124 unsigned long flags;
4126 local_irq_save(flags);
4127 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4128 local_irq_restore(flags);
4130 EXPORT_SYMBOL(__napi_schedule);
4132 void __napi_complete(struct napi_struct *n)
4134 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4135 BUG_ON(n->gro_list);
4137 list_del(&n->poll_list);
4138 smp_mb__before_clear_bit();
4139 clear_bit(NAPI_STATE_SCHED, &n->state);
4141 EXPORT_SYMBOL(__napi_complete);
4143 void napi_complete(struct napi_struct *n)
4145 unsigned long flags;
4148 * don't let napi dequeue from the cpu poll list
4149 * just in case its running on a different cpu
4151 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4154 napi_gro_flush(n, false);
4155 local_irq_save(flags);
4157 local_irq_restore(flags);
4159 EXPORT_SYMBOL(napi_complete);
4161 /* must be called under rcu_read_lock(), as we dont take a reference */
4162 struct napi_struct *napi_by_id(unsigned int napi_id)
4164 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4165 struct napi_struct *napi;
4167 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4168 if (napi->napi_id == napi_id)
4173 EXPORT_SYMBOL_GPL(napi_by_id);
4175 void napi_hash_add(struct napi_struct *napi)
4177 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4179 spin_lock(&napi_hash_lock);
4181 /* 0 is not a valid id, we also skip an id that is taken
4182 * we expect both events to be extremely rare
4185 while (!napi->napi_id) {
4186 napi->napi_id = ++napi_gen_id;
4187 if (napi_by_id(napi->napi_id))
4191 hlist_add_head_rcu(&napi->napi_hash_node,
4192 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4194 spin_unlock(&napi_hash_lock);
4197 EXPORT_SYMBOL_GPL(napi_hash_add);
4199 /* Warning : caller is responsible to make sure rcu grace period
4200 * is respected before freeing memory containing @napi
4202 void napi_hash_del(struct napi_struct *napi)
4204 spin_lock(&napi_hash_lock);
4206 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4207 hlist_del_rcu(&napi->napi_hash_node);
4209 spin_unlock(&napi_hash_lock);
4211 EXPORT_SYMBOL_GPL(napi_hash_del);
4213 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4214 int (*poll)(struct napi_struct *, int), int weight)
4216 INIT_LIST_HEAD(&napi->poll_list);
4217 napi->gro_count = 0;
4218 napi->gro_list = NULL;
4221 if (weight > NAPI_POLL_WEIGHT)
4222 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4224 napi->weight = weight;
4225 list_add(&napi->dev_list, &dev->napi_list);
4227 #ifdef CONFIG_NETPOLL
4228 spin_lock_init(&napi->poll_lock);
4229 napi->poll_owner = -1;
4231 set_bit(NAPI_STATE_SCHED, &napi->state);
4233 EXPORT_SYMBOL(netif_napi_add);
4235 void netif_napi_del(struct napi_struct *napi)
4237 list_del_init(&napi->dev_list);
4238 napi_free_frags(napi);
4240 kfree_skb_list(napi->gro_list);
4241 napi->gro_list = NULL;
4242 napi->gro_count = 0;
4244 EXPORT_SYMBOL(netif_napi_del);
4246 static void net_rx_action(struct softirq_action *h)
4248 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4249 unsigned long time_limit = jiffies + 2;
4250 int budget = netdev_budget;
4253 local_irq_disable();
4255 while (!list_empty(&sd->poll_list)) {
4256 struct napi_struct *n;
4259 /* If softirq window is exhuasted then punt.
4260 * Allow this to run for 2 jiffies since which will allow
4261 * an average latency of 1.5/HZ.
4263 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4268 /* Even though interrupts have been re-enabled, this
4269 * access is safe because interrupts can only add new
4270 * entries to the tail of this list, and only ->poll()
4271 * calls can remove this head entry from the list.
4273 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4275 have = netpoll_poll_lock(n);
4279 /* This NAPI_STATE_SCHED test is for avoiding a race
4280 * with netpoll's poll_napi(). Only the entity which
4281 * obtains the lock and sees NAPI_STATE_SCHED set will
4282 * actually make the ->poll() call. Therefore we avoid
4283 * accidentally calling ->poll() when NAPI is not scheduled.
4286 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4287 work = n->poll(n, weight);
4291 WARN_ON_ONCE(work > weight);
4295 local_irq_disable();
4297 /* Drivers must not modify the NAPI state if they
4298 * consume the entire weight. In such cases this code
4299 * still "owns" the NAPI instance and therefore can
4300 * move the instance around on the list at-will.
4302 if (unlikely(work == weight)) {
4303 if (unlikely(napi_disable_pending(n))) {
4306 local_irq_disable();
4309 /* flush too old packets
4310 * If HZ < 1000, flush all packets.
4313 napi_gro_flush(n, HZ >= 1000);
4314 local_irq_disable();
4316 list_move_tail(&n->poll_list, &sd->poll_list);
4320 netpoll_poll_unlock(have);
4323 net_rps_action_and_irq_enable(sd);
4325 #ifdef CONFIG_NET_DMA
4327 * There may not be any more sk_buffs coming right now, so push
4328 * any pending DMA copies to hardware
4330 dma_issue_pending_all();
4337 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4341 struct netdev_adjacent {
4342 struct net_device *dev;
4344 /* upper master flag, there can only be one master device per list */
4347 /* counter for the number of times this device was added to us */
4350 /* private field for the users */
4353 struct list_head list;
4354 struct rcu_head rcu;
4357 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4358 struct net_device *adj_dev,
4359 struct list_head *adj_list)
4361 struct netdev_adjacent *adj;
4363 list_for_each_entry(adj, adj_list, list) {
4364 if (adj->dev == adj_dev)
4371 * netdev_has_upper_dev - Check if device is linked to an upper device
4373 * @upper_dev: upper device to check
4375 * Find out if a device is linked to specified upper device and return true
4376 * in case it is. Note that this checks only immediate upper device,
4377 * not through a complete stack of devices. The caller must hold the RTNL lock.
4379 bool netdev_has_upper_dev(struct net_device *dev,
4380 struct net_device *upper_dev)
4384 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4386 EXPORT_SYMBOL(netdev_has_upper_dev);
4389 * netdev_has_any_upper_dev - Check if device is linked to some device
4392 * Find out if a device is linked to an upper device and return true in case
4393 * it is. The caller must hold the RTNL lock.
4395 static bool netdev_has_any_upper_dev(struct net_device *dev)
4399 return !list_empty(&dev->all_adj_list.upper);
4403 * netdev_master_upper_dev_get - Get master upper device
4406 * Find a master upper device and return pointer to it or NULL in case
4407 * it's not there. The caller must hold the RTNL lock.
4409 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4411 struct netdev_adjacent *upper;
4415 if (list_empty(&dev->adj_list.upper))
4418 upper = list_first_entry(&dev->adj_list.upper,
4419 struct netdev_adjacent, list);
4420 if (likely(upper->master))
4424 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4426 void *netdev_adjacent_get_private(struct list_head *adj_list)
4428 struct netdev_adjacent *adj;
4430 adj = list_entry(adj_list, struct netdev_adjacent, list);
4432 return adj->private;
4434 EXPORT_SYMBOL(netdev_adjacent_get_private);
4437 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4439 * @iter: list_head ** of the current position
4441 * Gets the next device from the dev's upper list, starting from iter
4442 * position. The caller must hold RCU read lock.
4444 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4445 struct list_head **iter)
4447 struct netdev_adjacent *upper;
4449 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4451 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4453 if (&upper->list == &dev->all_adj_list.upper)
4456 *iter = &upper->list;
4460 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4463 * netdev_lower_get_next_private - Get the next ->private from the
4464 * lower neighbour list
4466 * @iter: list_head ** of the current position
4468 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4469 * list, starting from iter position. The caller must hold either hold the
4470 * RTNL lock or its own locking that guarantees that the neighbour lower
4471 * list will remain unchainged.
4473 void *netdev_lower_get_next_private(struct net_device *dev,
4474 struct list_head **iter)
4476 struct netdev_adjacent *lower;
4478 lower = list_entry(*iter, struct netdev_adjacent, list);
4480 if (&lower->list == &dev->adj_list.lower)
4484 *iter = lower->list.next;
4486 return lower->private;
4488 EXPORT_SYMBOL(netdev_lower_get_next_private);
4491 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4492 * lower neighbour list, RCU
4495 * @iter: list_head ** of the current position
4497 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4498 * list, starting from iter position. The caller must hold RCU read lock.
4500 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4501 struct list_head **iter)
4503 struct netdev_adjacent *lower;
4505 WARN_ON_ONCE(!rcu_read_lock_held());
4507 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4509 if (&lower->list == &dev->adj_list.lower)
4513 *iter = &lower->list;
4515 return lower->private;
4517 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4520 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4521 * lower neighbour list, RCU
4525 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4526 * list. The caller must hold RCU read lock.
4528 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4530 struct netdev_adjacent *lower;
4532 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4533 struct netdev_adjacent, list);
4535 return lower->private;
4538 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4541 * netdev_master_upper_dev_get_rcu - Get master upper device
4544 * Find a master upper device and return pointer to it or NULL in case
4545 * it's not there. The caller must hold the RCU read lock.
4547 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4549 struct netdev_adjacent *upper;
4551 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4552 struct netdev_adjacent, list);
4553 if (upper && likely(upper->master))
4557 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4559 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4560 struct net_device *adj_dev,
4561 struct list_head *dev_list,
4562 void *private, bool master)
4564 struct netdev_adjacent *adj;
4565 char linkname[IFNAMSIZ+7];
4568 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4575 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4580 adj->master = master;
4582 adj->private = private;
4585 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4586 adj_dev->name, dev->name, adj_dev->name);
4588 if (dev_list == &dev->adj_list.lower) {
4589 sprintf(linkname, "lower_%s", adj_dev->name);
4590 ret = sysfs_create_link(&(dev->dev.kobj),
4591 &(adj_dev->dev.kobj), linkname);
4594 } else if (dev_list == &dev->adj_list.upper) {
4595 sprintf(linkname, "upper_%s", adj_dev->name);
4596 ret = sysfs_create_link(&(dev->dev.kobj),
4597 &(adj_dev->dev.kobj), linkname);
4602 /* Ensure that master link is always the first item in list. */
4604 ret = sysfs_create_link(&(dev->dev.kobj),
4605 &(adj_dev->dev.kobj), "master");
4607 goto remove_symlinks;
4609 list_add_rcu(&adj->list, dev_list);
4611 list_add_tail_rcu(&adj->list, dev_list);
4617 if (dev_list == &dev->adj_list.lower) {
4618 sprintf(linkname, "lower_%s", adj_dev->name);
4619 sysfs_remove_link(&(dev->dev.kobj), linkname);
4620 } else if (dev_list == &dev->adj_list.upper) {
4621 sprintf(linkname, "upper_%s", adj_dev->name);
4622 sysfs_remove_link(&(dev->dev.kobj), linkname);
4632 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4633 struct net_device *adj_dev,
4634 struct list_head *dev_list)
4636 struct netdev_adjacent *adj;
4637 char linkname[IFNAMSIZ+7];
4639 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4642 pr_err("tried to remove device %s from %s\n",
4643 dev->name, adj_dev->name);
4647 if (adj->ref_nr > 1) {
4648 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4655 sysfs_remove_link(&(dev->dev.kobj), "master");
4657 if (dev_list == &dev->adj_list.lower) {
4658 sprintf(linkname, "lower_%s", adj_dev->name);
4659 sysfs_remove_link(&(dev->dev.kobj), linkname);
4660 } else if (dev_list == &dev->adj_list.upper) {
4661 sprintf(linkname, "upper_%s", adj_dev->name);
4662 sysfs_remove_link(&(dev->dev.kobj), linkname);
4665 list_del_rcu(&adj->list);
4666 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4667 adj_dev->name, dev->name, adj_dev->name);
4669 kfree_rcu(adj, rcu);
4672 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4673 struct net_device *upper_dev,
4674 struct list_head *up_list,
4675 struct list_head *down_list,
4676 void *private, bool master)
4680 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4685 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4688 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4695 static int __netdev_adjacent_dev_link(struct net_device *dev,
4696 struct net_device *upper_dev)
4698 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4699 &dev->all_adj_list.upper,
4700 &upper_dev->all_adj_list.lower,
4704 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4705 struct net_device *upper_dev,
4706 struct list_head *up_list,
4707 struct list_head *down_list)
4709 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4710 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4713 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4714 struct net_device *upper_dev)
4716 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4717 &dev->all_adj_list.upper,
4718 &upper_dev->all_adj_list.lower);
4721 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4722 struct net_device *upper_dev,
4723 void *private, bool master)
4725 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4730 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4731 &dev->adj_list.upper,
4732 &upper_dev->adj_list.lower,
4735 __netdev_adjacent_dev_unlink(dev, upper_dev);
4742 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4743 struct net_device *upper_dev)
4745 __netdev_adjacent_dev_unlink(dev, upper_dev);
4746 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4747 &dev->adj_list.upper,
4748 &upper_dev->adj_list.lower);
4751 static int __netdev_upper_dev_link(struct net_device *dev,
4752 struct net_device *upper_dev, bool master,
4755 struct netdev_adjacent *i, *j, *to_i, *to_j;
4760 if (dev == upper_dev)
4763 /* To prevent loops, check if dev is not upper device to upper_dev. */
4764 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4767 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4770 if (master && netdev_master_upper_dev_get(dev))
4773 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4778 /* Now that we linked these devs, make all the upper_dev's
4779 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4780 * versa, and don't forget the devices itself. All of these
4781 * links are non-neighbours.
4783 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4784 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4785 pr_debug("Interlinking %s with %s, non-neighbour\n",
4786 i->dev->name, j->dev->name);
4787 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4793 /* add dev to every upper_dev's upper device */
4794 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4795 pr_debug("linking %s's upper device %s with %s\n",
4796 upper_dev->name, i->dev->name, dev->name);
4797 ret = __netdev_adjacent_dev_link(dev, i->dev);
4799 goto rollback_upper_mesh;
4802 /* add upper_dev to every dev's lower device */
4803 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4804 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4805 i->dev->name, upper_dev->name);
4806 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4808 goto rollback_lower_mesh;
4811 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4814 rollback_lower_mesh:
4816 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4819 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4824 rollback_upper_mesh:
4826 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4829 __netdev_adjacent_dev_unlink(dev, i->dev);
4837 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4838 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4839 if (i == to_i && j == to_j)
4841 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4847 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4853 * netdev_upper_dev_link - Add a link to the upper device
4855 * @upper_dev: new upper device
4857 * Adds a link to device which is upper to this one. The caller must hold
4858 * the RTNL lock. On a failure a negative errno code is returned.
4859 * On success the reference counts are adjusted and the function
4862 int netdev_upper_dev_link(struct net_device *dev,
4863 struct net_device *upper_dev)
4865 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4867 EXPORT_SYMBOL(netdev_upper_dev_link);
4870 * netdev_master_upper_dev_link - Add a master link to the upper device
4872 * @upper_dev: new upper device
4874 * Adds a link to device which is upper to this one. In this case, only
4875 * one master upper device can be linked, although other non-master devices
4876 * might be linked as well. The caller must hold the RTNL lock.
4877 * On a failure a negative errno code is returned. On success the reference
4878 * counts are adjusted and the function returns zero.
4880 int netdev_master_upper_dev_link(struct net_device *dev,
4881 struct net_device *upper_dev)
4883 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4885 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4887 int netdev_master_upper_dev_link_private(struct net_device *dev,
4888 struct net_device *upper_dev,
4891 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4893 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4896 * netdev_upper_dev_unlink - Removes a link to upper device
4898 * @upper_dev: new upper device
4900 * Removes a link to device which is upper to this one. The caller must hold
4903 void netdev_upper_dev_unlink(struct net_device *dev,
4904 struct net_device *upper_dev)
4906 struct netdev_adjacent *i, *j;
4909 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4911 /* Here is the tricky part. We must remove all dev's lower
4912 * devices from all upper_dev's upper devices and vice
4913 * versa, to maintain the graph relationship.
4915 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4916 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
4917 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4919 /* remove also the devices itself from lower/upper device
4922 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4923 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4925 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
4926 __netdev_adjacent_dev_unlink(dev, i->dev);
4928 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4930 EXPORT_SYMBOL(netdev_upper_dev_unlink);
4932 void *netdev_lower_dev_get_private(struct net_device *dev,
4933 struct net_device *lower_dev)
4935 struct netdev_adjacent *lower;
4939 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
4943 return lower->private;
4945 EXPORT_SYMBOL(netdev_lower_dev_get_private);
4947 static void dev_change_rx_flags(struct net_device *dev, int flags)
4949 const struct net_device_ops *ops = dev->netdev_ops;
4951 if (ops->ndo_change_rx_flags)
4952 ops->ndo_change_rx_flags(dev, flags);
4955 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
4957 unsigned int old_flags = dev->flags;
4963 dev->flags |= IFF_PROMISC;
4964 dev->promiscuity += inc;
4965 if (dev->promiscuity == 0) {
4968 * If inc causes overflow, untouch promisc and return error.
4971 dev->flags &= ~IFF_PROMISC;
4973 dev->promiscuity -= inc;
4974 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
4979 if (dev->flags != old_flags) {
4980 pr_info("device %s %s promiscuous mode\n",
4982 dev->flags & IFF_PROMISC ? "entered" : "left");
4983 if (audit_enabled) {
4984 current_uid_gid(&uid, &gid);
4985 audit_log(current->audit_context, GFP_ATOMIC,
4986 AUDIT_ANOM_PROMISCUOUS,
4987 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
4988 dev->name, (dev->flags & IFF_PROMISC),
4989 (old_flags & IFF_PROMISC),
4990 from_kuid(&init_user_ns, audit_get_loginuid(current)),
4991 from_kuid(&init_user_ns, uid),
4992 from_kgid(&init_user_ns, gid),
4993 audit_get_sessionid(current));
4996 dev_change_rx_flags(dev, IFF_PROMISC);
4999 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5004 * dev_set_promiscuity - update promiscuity count on a device
5008 * Add or remove promiscuity from a device. While the count in the device
5009 * remains above zero the interface remains promiscuous. Once it hits zero
5010 * the device reverts back to normal filtering operation. A negative inc
5011 * value is used to drop promiscuity on the device.
5012 * Return 0 if successful or a negative errno code on error.
5014 int dev_set_promiscuity(struct net_device *dev, int inc)
5016 unsigned int old_flags = dev->flags;
5019 err = __dev_set_promiscuity(dev, inc, true);
5022 if (dev->flags != old_flags)
5023 dev_set_rx_mode(dev);
5026 EXPORT_SYMBOL(dev_set_promiscuity);
5028 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5030 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5034 dev->flags |= IFF_ALLMULTI;
5035 dev->allmulti += inc;
5036 if (dev->allmulti == 0) {
5039 * If inc causes overflow, untouch allmulti and return error.
5042 dev->flags &= ~IFF_ALLMULTI;
5044 dev->allmulti -= inc;
5045 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5050 if (dev->flags ^ old_flags) {
5051 dev_change_rx_flags(dev, IFF_ALLMULTI);
5052 dev_set_rx_mode(dev);
5054 __dev_notify_flags(dev, old_flags,
5055 dev->gflags ^ old_gflags);
5061 * dev_set_allmulti - update allmulti count on a device
5065 * Add or remove reception of all multicast frames to a device. While the
5066 * count in the device remains above zero the interface remains listening
5067 * to all interfaces. Once it hits zero the device reverts back to normal
5068 * filtering operation. A negative @inc value is used to drop the counter
5069 * when releasing a resource needing all multicasts.
5070 * Return 0 if successful or a negative errno code on error.
5073 int dev_set_allmulti(struct net_device *dev, int inc)
5075 return __dev_set_allmulti(dev, inc, true);
5077 EXPORT_SYMBOL(dev_set_allmulti);
5080 * Upload unicast and multicast address lists to device and
5081 * configure RX filtering. When the device doesn't support unicast
5082 * filtering it is put in promiscuous mode while unicast addresses
5085 void __dev_set_rx_mode(struct net_device *dev)
5087 const struct net_device_ops *ops = dev->netdev_ops;
5089 /* dev_open will call this function so the list will stay sane. */
5090 if (!(dev->flags&IFF_UP))
5093 if (!netif_device_present(dev))
5096 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5097 /* Unicast addresses changes may only happen under the rtnl,
5098 * therefore calling __dev_set_promiscuity here is safe.
5100 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5101 __dev_set_promiscuity(dev, 1, false);
5102 dev->uc_promisc = true;
5103 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5104 __dev_set_promiscuity(dev, -1, false);
5105 dev->uc_promisc = false;
5109 if (ops->ndo_set_rx_mode)
5110 ops->ndo_set_rx_mode(dev);
5113 void dev_set_rx_mode(struct net_device *dev)
5115 netif_addr_lock_bh(dev);
5116 __dev_set_rx_mode(dev);
5117 netif_addr_unlock_bh(dev);
5121 * dev_get_flags - get flags reported to userspace
5124 * Get the combination of flag bits exported through APIs to userspace.
5126 unsigned int dev_get_flags(const struct net_device *dev)
5130 flags = (dev->flags & ~(IFF_PROMISC |
5135 (dev->gflags & (IFF_PROMISC |
5138 if (netif_running(dev)) {
5139 if (netif_oper_up(dev))
5140 flags |= IFF_RUNNING;
5141 if (netif_carrier_ok(dev))
5142 flags |= IFF_LOWER_UP;
5143 if (netif_dormant(dev))
5144 flags |= IFF_DORMANT;
5149 EXPORT_SYMBOL(dev_get_flags);
5151 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5153 unsigned int old_flags = dev->flags;
5159 * Set the flags on our device.
5162 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5163 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5165 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5169 * Load in the correct multicast list now the flags have changed.
5172 if ((old_flags ^ flags) & IFF_MULTICAST)
5173 dev_change_rx_flags(dev, IFF_MULTICAST);
5175 dev_set_rx_mode(dev);
5178 * Have we downed the interface. We handle IFF_UP ourselves
5179 * according to user attempts to set it, rather than blindly
5184 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5185 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5188 dev_set_rx_mode(dev);
5191 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5192 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5193 unsigned int old_flags = dev->flags;
5195 dev->gflags ^= IFF_PROMISC;
5197 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5198 if (dev->flags != old_flags)
5199 dev_set_rx_mode(dev);
5202 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5203 is important. Some (broken) drivers set IFF_PROMISC, when
5204 IFF_ALLMULTI is requested not asking us and not reporting.
5206 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5207 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5209 dev->gflags ^= IFF_ALLMULTI;
5210 __dev_set_allmulti(dev, inc, false);
5216 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5217 unsigned int gchanges)
5219 unsigned int changes = dev->flags ^ old_flags;
5222 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5224 if (changes & IFF_UP) {
5225 if (dev->flags & IFF_UP)
5226 call_netdevice_notifiers(NETDEV_UP, dev);
5228 call_netdevice_notifiers(NETDEV_DOWN, dev);
5231 if (dev->flags & IFF_UP &&
5232 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5233 struct netdev_notifier_change_info change_info;
5235 change_info.flags_changed = changes;
5236 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5242 * dev_change_flags - change device settings
5244 * @flags: device state flags
5246 * Change settings on device based state flags. The flags are
5247 * in the userspace exported format.
5249 int dev_change_flags(struct net_device *dev, unsigned int flags)
5252 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5254 ret = __dev_change_flags(dev, flags);
5258 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5259 __dev_notify_flags(dev, old_flags, changes);
5262 EXPORT_SYMBOL(dev_change_flags);
5265 * dev_set_mtu - Change maximum transfer unit
5267 * @new_mtu: new transfer unit
5269 * Change the maximum transfer size of the network device.
5271 int dev_set_mtu(struct net_device *dev, int new_mtu)
5273 const struct net_device_ops *ops = dev->netdev_ops;
5276 if (new_mtu == dev->mtu)
5279 /* MTU must be positive. */
5283 if (!netif_device_present(dev))
5287 if (ops->ndo_change_mtu)
5288 err = ops->ndo_change_mtu(dev, new_mtu);
5293 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5296 EXPORT_SYMBOL(dev_set_mtu);
5299 * dev_set_group - Change group this device belongs to
5301 * @new_group: group this device should belong to
5303 void dev_set_group(struct net_device *dev, int new_group)
5305 dev->group = new_group;
5307 EXPORT_SYMBOL(dev_set_group);
5310 * dev_set_mac_address - Change Media Access Control Address
5314 * Change the hardware (MAC) address of the device
5316 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5318 const struct net_device_ops *ops = dev->netdev_ops;
5321 if (!ops->ndo_set_mac_address)
5323 if (sa->sa_family != dev->type)
5325 if (!netif_device_present(dev))
5327 err = ops->ndo_set_mac_address(dev, sa);
5330 dev->addr_assign_type = NET_ADDR_SET;
5331 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5332 add_device_randomness(dev->dev_addr, dev->addr_len);
5335 EXPORT_SYMBOL(dev_set_mac_address);
5338 * dev_change_carrier - Change device carrier
5340 * @new_carrier: new value
5342 * Change device carrier
5344 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5346 const struct net_device_ops *ops = dev->netdev_ops;
5348 if (!ops->ndo_change_carrier)
5350 if (!netif_device_present(dev))
5352 return ops->ndo_change_carrier(dev, new_carrier);
5354 EXPORT_SYMBOL(dev_change_carrier);
5357 * dev_get_phys_port_id - Get device physical port ID
5361 * Get device physical port ID
5363 int dev_get_phys_port_id(struct net_device *dev,
5364 struct netdev_phys_port_id *ppid)
5366 const struct net_device_ops *ops = dev->netdev_ops;
5368 if (!ops->ndo_get_phys_port_id)
5370 return ops->ndo_get_phys_port_id(dev, ppid);
5372 EXPORT_SYMBOL(dev_get_phys_port_id);
5375 * dev_new_index - allocate an ifindex
5376 * @net: the applicable net namespace
5378 * Returns a suitable unique value for a new device interface
5379 * number. The caller must hold the rtnl semaphore or the
5380 * dev_base_lock to be sure it remains unique.
5382 static int dev_new_index(struct net *net)
5384 int ifindex = net->ifindex;
5388 if (!__dev_get_by_index(net, ifindex))
5389 return net->ifindex = ifindex;
5393 /* Delayed registration/unregisteration */
5394 static LIST_HEAD(net_todo_list);
5395 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5397 static void net_set_todo(struct net_device *dev)
5399 list_add_tail(&dev->todo_list, &net_todo_list);
5400 dev_net(dev)->dev_unreg_count++;
5403 static void rollback_registered_many(struct list_head *head)
5405 struct net_device *dev, *tmp;
5406 LIST_HEAD(close_head);
5408 BUG_ON(dev_boot_phase);
5411 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5412 /* Some devices call without registering
5413 * for initialization unwind. Remove those
5414 * devices and proceed with the remaining.
5416 if (dev->reg_state == NETREG_UNINITIALIZED) {
5417 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5421 list_del(&dev->unreg_list);
5424 dev->dismantle = true;
5425 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5428 /* If device is running, close it first. */
5429 list_for_each_entry(dev, head, unreg_list)
5430 list_add_tail(&dev->close_list, &close_head);
5431 dev_close_many(&close_head);
5433 list_for_each_entry(dev, head, unreg_list) {
5434 /* And unlink it from device chain. */
5435 unlist_netdevice(dev);
5437 dev->reg_state = NETREG_UNREGISTERING;
5442 list_for_each_entry(dev, head, unreg_list) {
5443 /* Shutdown queueing discipline. */
5447 /* Notify protocols, that we are about to destroy
5448 this device. They should clean all the things.
5450 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5452 if (!dev->rtnl_link_ops ||
5453 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5454 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5457 * Flush the unicast and multicast chains
5462 if (dev->netdev_ops->ndo_uninit)
5463 dev->netdev_ops->ndo_uninit(dev);
5465 /* Notifier chain MUST detach us all upper devices. */
5466 WARN_ON(netdev_has_any_upper_dev(dev));
5468 /* Remove entries from kobject tree */
5469 netdev_unregister_kobject(dev);
5471 /* Remove XPS queueing entries */
5472 netif_reset_xps_queues_gt(dev, 0);
5478 list_for_each_entry(dev, head, unreg_list)
5482 static void rollback_registered(struct net_device *dev)
5486 list_add(&dev->unreg_list, &single);
5487 rollback_registered_many(&single);
5491 static netdev_features_t netdev_fix_features(struct net_device *dev,
5492 netdev_features_t features)
5494 /* Fix illegal checksum combinations */
5495 if ((features & NETIF_F_HW_CSUM) &&
5496 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5497 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5498 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5501 /* TSO requires that SG is present as well. */
5502 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5503 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5504 features &= ~NETIF_F_ALL_TSO;
5507 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5508 !(features & NETIF_F_IP_CSUM)) {
5509 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5510 features &= ~NETIF_F_TSO;
5511 features &= ~NETIF_F_TSO_ECN;
5514 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5515 !(features & NETIF_F_IPV6_CSUM)) {
5516 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5517 features &= ~NETIF_F_TSO6;
5520 /* TSO ECN requires that TSO is present as well. */
5521 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5522 features &= ~NETIF_F_TSO_ECN;
5524 /* Software GSO depends on SG. */
5525 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5526 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5527 features &= ~NETIF_F_GSO;
5530 /* UFO needs SG and checksumming */
5531 if (features & NETIF_F_UFO) {
5532 /* maybe split UFO into V4 and V6? */
5533 if (!((features & NETIF_F_GEN_CSUM) ||
5534 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5535 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5537 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5538 features &= ~NETIF_F_UFO;
5541 if (!(features & NETIF_F_SG)) {
5543 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5544 features &= ~NETIF_F_UFO;
5551 int __netdev_update_features(struct net_device *dev)
5553 netdev_features_t features;
5558 features = netdev_get_wanted_features(dev);
5560 if (dev->netdev_ops->ndo_fix_features)
5561 features = dev->netdev_ops->ndo_fix_features(dev, features);
5563 /* driver might be less strict about feature dependencies */
5564 features = netdev_fix_features(dev, features);
5566 if (dev->features == features)
5569 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5570 &dev->features, &features);
5572 if (dev->netdev_ops->ndo_set_features)
5573 err = dev->netdev_ops->ndo_set_features(dev, features);
5575 if (unlikely(err < 0)) {
5577 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5578 err, &features, &dev->features);
5583 dev->features = features;
5589 * netdev_update_features - recalculate device features
5590 * @dev: the device to check
5592 * Recalculate dev->features set and send notifications if it
5593 * has changed. Should be called after driver or hardware dependent
5594 * conditions might have changed that influence the features.
5596 void netdev_update_features(struct net_device *dev)
5598 if (__netdev_update_features(dev))
5599 netdev_features_change(dev);
5601 EXPORT_SYMBOL(netdev_update_features);
5604 * netdev_change_features - recalculate device features
5605 * @dev: the device to check
5607 * Recalculate dev->features set and send notifications even
5608 * if they have not changed. Should be called instead of
5609 * netdev_update_features() if also dev->vlan_features might
5610 * have changed to allow the changes to be propagated to stacked
5613 void netdev_change_features(struct net_device *dev)
5615 __netdev_update_features(dev);
5616 netdev_features_change(dev);
5618 EXPORT_SYMBOL(netdev_change_features);
5621 * netif_stacked_transfer_operstate - transfer operstate
5622 * @rootdev: the root or lower level device to transfer state from
5623 * @dev: the device to transfer operstate to
5625 * Transfer operational state from root to device. This is normally
5626 * called when a stacking relationship exists between the root
5627 * device and the device(a leaf device).
5629 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5630 struct net_device *dev)
5632 if (rootdev->operstate == IF_OPER_DORMANT)
5633 netif_dormant_on(dev);
5635 netif_dormant_off(dev);
5637 if (netif_carrier_ok(rootdev)) {
5638 if (!netif_carrier_ok(dev))
5639 netif_carrier_on(dev);
5641 if (netif_carrier_ok(dev))
5642 netif_carrier_off(dev);
5645 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5648 static int netif_alloc_rx_queues(struct net_device *dev)
5650 unsigned int i, count = dev->num_rx_queues;
5651 struct netdev_rx_queue *rx;
5655 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5661 for (i = 0; i < count; i++)
5667 static void netdev_init_one_queue(struct net_device *dev,
5668 struct netdev_queue *queue, void *_unused)
5670 /* Initialize queue lock */
5671 spin_lock_init(&queue->_xmit_lock);
5672 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5673 queue->xmit_lock_owner = -1;
5674 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5677 dql_init(&queue->dql, HZ);
5681 static void netif_free_tx_queues(struct net_device *dev)
5683 if (is_vmalloc_addr(dev->_tx))
5689 static int netif_alloc_netdev_queues(struct net_device *dev)
5691 unsigned int count = dev->num_tx_queues;
5692 struct netdev_queue *tx;
5693 size_t sz = count * sizeof(*tx);
5695 BUG_ON(count < 1 || count > 0xffff);
5697 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5705 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5706 spin_lock_init(&dev->tx_global_lock);
5712 * register_netdevice - register a network device
5713 * @dev: device to register
5715 * Take a completed network device structure and add it to the kernel
5716 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5717 * chain. 0 is returned on success. A negative errno code is returned
5718 * on a failure to set up the device, or if the name is a duplicate.
5720 * Callers must hold the rtnl semaphore. You may want
5721 * register_netdev() instead of this.
5724 * The locking appears insufficient to guarantee two parallel registers
5725 * will not get the same name.
5728 int register_netdevice(struct net_device *dev)
5731 struct net *net = dev_net(dev);
5733 BUG_ON(dev_boot_phase);
5738 /* When net_device's are persistent, this will be fatal. */
5739 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5742 spin_lock_init(&dev->addr_list_lock);
5743 netdev_set_addr_lockdep_class(dev);
5747 ret = dev_get_valid_name(net, dev, dev->name);
5751 /* Init, if this function is available */
5752 if (dev->netdev_ops->ndo_init) {
5753 ret = dev->netdev_ops->ndo_init(dev);
5761 if (((dev->hw_features | dev->features) &
5762 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5763 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5764 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5765 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5772 dev->ifindex = dev_new_index(net);
5773 else if (__dev_get_by_index(net, dev->ifindex))
5776 if (dev->iflink == -1)
5777 dev->iflink = dev->ifindex;
5779 /* Transfer changeable features to wanted_features and enable
5780 * software offloads (GSO and GRO).
5782 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5783 dev->features |= NETIF_F_SOFT_FEATURES;
5784 dev->wanted_features = dev->features & dev->hw_features;
5786 /* Turn on no cache copy if HW is doing checksum */
5787 if (!(dev->flags & IFF_LOOPBACK)) {
5788 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5789 if (dev->features & NETIF_F_ALL_CSUM) {
5790 dev->wanted_features |= NETIF_F_NOCACHE_COPY;
5791 dev->features |= NETIF_F_NOCACHE_COPY;
5795 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5797 dev->vlan_features |= NETIF_F_HIGHDMA;
5799 /* Make NETIF_F_SG inheritable to tunnel devices.
5801 dev->hw_enc_features |= NETIF_F_SG;
5803 /* Make NETIF_F_SG inheritable to MPLS.
5805 dev->mpls_features |= NETIF_F_SG;
5807 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5808 ret = notifier_to_errno(ret);
5812 ret = netdev_register_kobject(dev);
5815 dev->reg_state = NETREG_REGISTERED;
5817 __netdev_update_features(dev);
5820 * Default initial state at registry is that the
5821 * device is present.
5824 set_bit(__LINK_STATE_PRESENT, &dev->state);
5826 linkwatch_init_dev(dev);
5828 dev_init_scheduler(dev);
5830 list_netdevice(dev);
5831 add_device_randomness(dev->dev_addr, dev->addr_len);
5833 /* If the device has permanent device address, driver should
5834 * set dev_addr and also addr_assign_type should be set to
5835 * NET_ADDR_PERM (default value).
5837 if (dev->addr_assign_type == NET_ADDR_PERM)
5838 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5840 /* Notify protocols, that a new device appeared. */
5841 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5842 ret = notifier_to_errno(ret);
5844 rollback_registered(dev);
5845 dev->reg_state = NETREG_UNREGISTERED;
5848 * Prevent userspace races by waiting until the network
5849 * device is fully setup before sending notifications.
5851 if (!dev->rtnl_link_ops ||
5852 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5853 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5859 if (dev->netdev_ops->ndo_uninit)
5860 dev->netdev_ops->ndo_uninit(dev);
5863 EXPORT_SYMBOL(register_netdevice);
5866 * init_dummy_netdev - init a dummy network device for NAPI
5867 * @dev: device to init
5869 * This takes a network device structure and initialize the minimum
5870 * amount of fields so it can be used to schedule NAPI polls without
5871 * registering a full blown interface. This is to be used by drivers
5872 * that need to tie several hardware interfaces to a single NAPI
5873 * poll scheduler due to HW limitations.
5875 int init_dummy_netdev(struct net_device *dev)
5877 /* Clear everything. Note we don't initialize spinlocks
5878 * are they aren't supposed to be taken by any of the
5879 * NAPI code and this dummy netdev is supposed to be
5880 * only ever used for NAPI polls
5882 memset(dev, 0, sizeof(struct net_device));
5884 /* make sure we BUG if trying to hit standard
5885 * register/unregister code path
5887 dev->reg_state = NETREG_DUMMY;
5889 /* NAPI wants this */
5890 INIT_LIST_HEAD(&dev->napi_list);
5892 /* a dummy interface is started by default */
5893 set_bit(__LINK_STATE_PRESENT, &dev->state);
5894 set_bit(__LINK_STATE_START, &dev->state);
5896 /* Note : We dont allocate pcpu_refcnt for dummy devices,
5897 * because users of this 'device' dont need to change
5903 EXPORT_SYMBOL_GPL(init_dummy_netdev);
5907 * register_netdev - register a network device
5908 * @dev: device to register
5910 * Take a completed network device structure and add it to the kernel
5911 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5912 * chain. 0 is returned on success. A negative errno code is returned
5913 * on a failure to set up the device, or if the name is a duplicate.
5915 * This is a wrapper around register_netdevice that takes the rtnl semaphore
5916 * and expands the device name if you passed a format string to
5919 int register_netdev(struct net_device *dev)
5924 err = register_netdevice(dev);
5928 EXPORT_SYMBOL(register_netdev);
5930 int netdev_refcnt_read(const struct net_device *dev)
5934 for_each_possible_cpu(i)
5935 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5938 EXPORT_SYMBOL(netdev_refcnt_read);
5941 * netdev_wait_allrefs - wait until all references are gone.
5942 * @dev: target net_device
5944 * This is called when unregistering network devices.
5946 * Any protocol or device that holds a reference should register
5947 * for netdevice notification, and cleanup and put back the
5948 * reference if they receive an UNREGISTER event.
5949 * We can get stuck here if buggy protocols don't correctly
5952 static void netdev_wait_allrefs(struct net_device *dev)
5954 unsigned long rebroadcast_time, warning_time;
5957 linkwatch_forget_dev(dev);
5959 rebroadcast_time = warning_time = jiffies;
5960 refcnt = netdev_refcnt_read(dev);
5962 while (refcnt != 0) {
5963 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5966 /* Rebroadcast unregister notification */
5967 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5973 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
5974 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
5976 /* We must not have linkwatch events
5977 * pending on unregister. If this
5978 * happens, we simply run the queue
5979 * unscheduled, resulting in a noop
5982 linkwatch_run_queue();
5987 rebroadcast_time = jiffies;
5992 refcnt = netdev_refcnt_read(dev);
5994 if (time_after(jiffies, warning_time + 10 * HZ)) {
5995 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
5997 warning_time = jiffies;
6006 * register_netdevice(x1);
6007 * register_netdevice(x2);
6009 * unregister_netdevice(y1);
6010 * unregister_netdevice(y2);
6016 * We are invoked by rtnl_unlock().
6017 * This allows us to deal with problems:
6018 * 1) We can delete sysfs objects which invoke hotplug
6019 * without deadlocking with linkwatch via keventd.
6020 * 2) Since we run with the RTNL semaphore not held, we can sleep
6021 * safely in order to wait for the netdev refcnt to drop to zero.
6023 * We must not return until all unregister events added during
6024 * the interval the lock was held have been completed.
6026 void netdev_run_todo(void)
6028 struct list_head list;
6030 /* Snapshot list, allow later requests */
6031 list_replace_init(&net_todo_list, &list);
6036 /* Wait for rcu callbacks to finish before next phase */
6037 if (!list_empty(&list))
6040 while (!list_empty(&list)) {
6041 struct net_device *dev
6042 = list_first_entry(&list, struct net_device, todo_list);
6043 list_del(&dev->todo_list);
6046 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6049 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6050 pr_err("network todo '%s' but state %d\n",
6051 dev->name, dev->reg_state);
6056 dev->reg_state = NETREG_UNREGISTERED;
6058 on_each_cpu(flush_backlog, dev, 1);
6060 netdev_wait_allrefs(dev);
6063 BUG_ON(netdev_refcnt_read(dev));
6064 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6065 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6066 WARN_ON(dev->dn_ptr);
6068 if (dev->destructor)
6069 dev->destructor(dev);
6071 /* Report a network device has been unregistered */
6073 dev_net(dev)->dev_unreg_count--;
6075 wake_up(&netdev_unregistering_wq);
6077 /* Free network device */
6078 kobject_put(&dev->dev.kobj);
6082 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6083 * fields in the same order, with only the type differing.
6085 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6086 const struct net_device_stats *netdev_stats)
6088 #if BITS_PER_LONG == 64
6089 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6090 memcpy(stats64, netdev_stats, sizeof(*stats64));
6092 size_t i, n = sizeof(*stats64) / sizeof(u64);
6093 const unsigned long *src = (const unsigned long *)netdev_stats;
6094 u64 *dst = (u64 *)stats64;
6096 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6097 sizeof(*stats64) / sizeof(u64));
6098 for (i = 0; i < n; i++)
6102 EXPORT_SYMBOL(netdev_stats_to_stats64);
6105 * dev_get_stats - get network device statistics
6106 * @dev: device to get statistics from
6107 * @storage: place to store stats
6109 * Get network statistics from device. Return @storage.
6110 * The device driver may provide its own method by setting
6111 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6112 * otherwise the internal statistics structure is used.
6114 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6115 struct rtnl_link_stats64 *storage)
6117 const struct net_device_ops *ops = dev->netdev_ops;
6119 if (ops->ndo_get_stats64) {
6120 memset(storage, 0, sizeof(*storage));
6121 ops->ndo_get_stats64(dev, storage);
6122 } else if (ops->ndo_get_stats) {
6123 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6125 netdev_stats_to_stats64(storage, &dev->stats);
6127 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6130 EXPORT_SYMBOL(dev_get_stats);
6132 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6134 struct netdev_queue *queue = dev_ingress_queue(dev);
6136 #ifdef CONFIG_NET_CLS_ACT
6139 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6142 netdev_init_one_queue(dev, queue, NULL);
6143 queue->qdisc = &noop_qdisc;
6144 queue->qdisc_sleeping = &noop_qdisc;
6145 rcu_assign_pointer(dev->ingress_queue, queue);
6150 static const struct ethtool_ops default_ethtool_ops;
6152 void netdev_set_default_ethtool_ops(struct net_device *dev,
6153 const struct ethtool_ops *ops)
6155 if (dev->ethtool_ops == &default_ethtool_ops)
6156 dev->ethtool_ops = ops;
6158 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6160 void netdev_freemem(struct net_device *dev)
6162 char *addr = (char *)dev - dev->padded;
6164 if (is_vmalloc_addr(addr))
6171 * alloc_netdev_mqs - allocate network device
6172 * @sizeof_priv: size of private data to allocate space for
6173 * @name: device name format string
6174 * @setup: callback to initialize device
6175 * @txqs: the number of TX subqueues to allocate
6176 * @rxqs: the number of RX subqueues to allocate
6178 * Allocates a struct net_device with private data area for driver use
6179 * and performs basic initialization. Also allocates subquue structs
6180 * for each queue on the device.
6182 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6183 void (*setup)(struct net_device *),
6184 unsigned int txqs, unsigned int rxqs)
6186 struct net_device *dev;
6188 struct net_device *p;
6190 BUG_ON(strlen(name) >= sizeof(dev->name));
6193 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6199 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6204 alloc_size = sizeof(struct net_device);
6206 /* ensure 32-byte alignment of private area */
6207 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6208 alloc_size += sizeof_priv;
6210 /* ensure 32-byte alignment of whole construct */
6211 alloc_size += NETDEV_ALIGN - 1;
6213 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6215 p = vzalloc(alloc_size);
6219 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6220 dev->padded = (char *)dev - (char *)p;
6222 dev->pcpu_refcnt = alloc_percpu(int);
6223 if (!dev->pcpu_refcnt)
6226 if (dev_addr_init(dev))
6232 dev_net_set(dev, &init_net);
6234 dev->gso_max_size = GSO_MAX_SIZE;
6235 dev->gso_max_segs = GSO_MAX_SEGS;
6237 INIT_LIST_HEAD(&dev->napi_list);
6238 INIT_LIST_HEAD(&dev->unreg_list);
6239 INIT_LIST_HEAD(&dev->close_list);
6240 INIT_LIST_HEAD(&dev->link_watch_list);
6241 INIT_LIST_HEAD(&dev->adj_list.upper);
6242 INIT_LIST_HEAD(&dev->adj_list.lower);
6243 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6244 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6245 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6248 dev->num_tx_queues = txqs;
6249 dev->real_num_tx_queues = txqs;
6250 if (netif_alloc_netdev_queues(dev))
6254 dev->num_rx_queues = rxqs;
6255 dev->real_num_rx_queues = rxqs;
6256 if (netif_alloc_rx_queues(dev))
6260 strcpy(dev->name, name);
6261 dev->group = INIT_NETDEV_GROUP;
6262 if (!dev->ethtool_ops)
6263 dev->ethtool_ops = &default_ethtool_ops;
6271 free_percpu(dev->pcpu_refcnt);
6272 netif_free_tx_queues(dev);
6278 netdev_freemem(dev);
6281 EXPORT_SYMBOL(alloc_netdev_mqs);
6284 * free_netdev - free network device
6287 * This function does the last stage of destroying an allocated device
6288 * interface. The reference to the device object is released.
6289 * If this is the last reference then it will be freed.
6291 void free_netdev(struct net_device *dev)
6293 struct napi_struct *p, *n;
6295 release_net(dev_net(dev));
6297 netif_free_tx_queues(dev);
6302 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6304 /* Flush device addresses */
6305 dev_addr_flush(dev);
6307 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6310 free_percpu(dev->pcpu_refcnt);
6311 dev->pcpu_refcnt = NULL;
6313 /* Compatibility with error handling in drivers */
6314 if (dev->reg_state == NETREG_UNINITIALIZED) {
6315 netdev_freemem(dev);
6319 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6320 dev->reg_state = NETREG_RELEASED;
6322 /* will free via device release */
6323 put_device(&dev->dev);
6325 EXPORT_SYMBOL(free_netdev);
6328 * synchronize_net - Synchronize with packet receive processing
6330 * Wait for packets currently being received to be done.
6331 * Does not block later packets from starting.
6333 void synchronize_net(void)
6336 if (rtnl_is_locked())
6337 synchronize_rcu_expedited();
6341 EXPORT_SYMBOL(synchronize_net);
6344 * unregister_netdevice_queue - remove device from the kernel
6348 * This function shuts down a device interface and removes it
6349 * from the kernel tables.
6350 * If head not NULL, device is queued to be unregistered later.
6352 * Callers must hold the rtnl semaphore. You may want
6353 * unregister_netdev() instead of this.
6356 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6361 list_move_tail(&dev->unreg_list, head);
6363 rollback_registered(dev);
6364 /* Finish processing unregister after unlock */
6368 EXPORT_SYMBOL(unregister_netdevice_queue);
6371 * unregister_netdevice_many - unregister many devices
6372 * @head: list of devices
6374 void unregister_netdevice_many(struct list_head *head)
6376 struct net_device *dev;
6378 if (!list_empty(head)) {
6379 rollback_registered_many(head);
6380 list_for_each_entry(dev, head, unreg_list)
6384 EXPORT_SYMBOL(unregister_netdevice_many);
6387 * unregister_netdev - remove device from the kernel
6390 * This function shuts down a device interface and removes it
6391 * from the kernel tables.
6393 * This is just a wrapper for unregister_netdevice that takes
6394 * the rtnl semaphore. In general you want to use this and not
6395 * unregister_netdevice.
6397 void unregister_netdev(struct net_device *dev)
6400 unregister_netdevice(dev);
6403 EXPORT_SYMBOL(unregister_netdev);
6406 * dev_change_net_namespace - move device to different nethost namespace
6408 * @net: network namespace
6409 * @pat: If not NULL name pattern to try if the current device name
6410 * is already taken in the destination network namespace.
6412 * This function shuts down a device interface and moves it
6413 * to a new network namespace. On success 0 is returned, on
6414 * a failure a netagive errno code is returned.
6416 * Callers must hold the rtnl semaphore.
6419 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6425 /* Don't allow namespace local devices to be moved. */
6427 if (dev->features & NETIF_F_NETNS_LOCAL)
6430 /* Ensure the device has been registrered */
6431 if (dev->reg_state != NETREG_REGISTERED)
6434 /* Get out if there is nothing todo */
6436 if (net_eq(dev_net(dev), net))
6439 /* Pick the destination device name, and ensure
6440 * we can use it in the destination network namespace.
6443 if (__dev_get_by_name(net, dev->name)) {
6444 /* We get here if we can't use the current device name */
6447 if (dev_get_valid_name(net, dev, pat) < 0)
6452 * And now a mini version of register_netdevice unregister_netdevice.
6455 /* If device is running close it first. */
6458 /* And unlink it from device chain */
6460 unlist_netdevice(dev);
6464 /* Shutdown queueing discipline. */
6467 /* Notify protocols, that we are about to destroy
6468 this device. They should clean all the things.
6470 Note that dev->reg_state stays at NETREG_REGISTERED.
6471 This is wanted because this way 8021q and macvlan know
6472 the device is just moving and can keep their slaves up.
6474 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6476 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6477 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6480 * Flush the unicast and multicast chains
6485 /* Send a netdev-removed uevent to the old namespace */
6486 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6488 /* Actually switch the network namespace */
6489 dev_net_set(dev, net);
6491 /* If there is an ifindex conflict assign a new one */
6492 if (__dev_get_by_index(net, dev->ifindex)) {
6493 int iflink = (dev->iflink == dev->ifindex);
6494 dev->ifindex = dev_new_index(net);
6496 dev->iflink = dev->ifindex;
6499 /* Send a netdev-add uevent to the new namespace */
6500 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6502 /* Fixup kobjects */
6503 err = device_rename(&dev->dev, dev->name);
6506 /* Add the device back in the hashes */
6507 list_netdevice(dev);
6509 /* Notify protocols, that a new device appeared. */
6510 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6513 * Prevent userspace races by waiting until the network
6514 * device is fully setup before sending notifications.
6516 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6523 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6525 static int dev_cpu_callback(struct notifier_block *nfb,
6526 unsigned long action,
6529 struct sk_buff **list_skb;
6530 struct sk_buff *skb;
6531 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6532 struct softnet_data *sd, *oldsd;
6534 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6537 local_irq_disable();
6538 cpu = smp_processor_id();
6539 sd = &per_cpu(softnet_data, cpu);
6540 oldsd = &per_cpu(softnet_data, oldcpu);
6542 /* Find end of our completion_queue. */
6543 list_skb = &sd->completion_queue;
6545 list_skb = &(*list_skb)->next;
6546 /* Append completion queue from offline CPU. */
6547 *list_skb = oldsd->completion_queue;
6548 oldsd->completion_queue = NULL;
6550 /* Append output queue from offline CPU. */
6551 if (oldsd->output_queue) {
6552 *sd->output_queue_tailp = oldsd->output_queue;
6553 sd->output_queue_tailp = oldsd->output_queue_tailp;
6554 oldsd->output_queue = NULL;
6555 oldsd->output_queue_tailp = &oldsd->output_queue;
6557 /* Append NAPI poll list from offline CPU. */
6558 if (!list_empty(&oldsd->poll_list)) {
6559 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6560 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6563 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6566 /* Process offline CPU's input_pkt_queue */
6567 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6569 input_queue_head_incr(oldsd);
6571 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6573 input_queue_head_incr(oldsd);
6581 * netdev_increment_features - increment feature set by one
6582 * @all: current feature set
6583 * @one: new feature set
6584 * @mask: mask feature set
6586 * Computes a new feature set after adding a device with feature set
6587 * @one to the master device with current feature set @all. Will not
6588 * enable anything that is off in @mask. Returns the new feature set.
6590 netdev_features_t netdev_increment_features(netdev_features_t all,
6591 netdev_features_t one, netdev_features_t mask)
6593 if (mask & NETIF_F_GEN_CSUM)
6594 mask |= NETIF_F_ALL_CSUM;
6595 mask |= NETIF_F_VLAN_CHALLENGED;
6597 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6598 all &= one | ~NETIF_F_ALL_FOR_ALL;
6600 /* If one device supports hw checksumming, set for all. */
6601 if (all & NETIF_F_GEN_CSUM)
6602 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6606 EXPORT_SYMBOL(netdev_increment_features);
6608 static struct hlist_head * __net_init netdev_create_hash(void)
6611 struct hlist_head *hash;
6613 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6615 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6616 INIT_HLIST_HEAD(&hash[i]);
6621 /* Initialize per network namespace state */
6622 static int __net_init netdev_init(struct net *net)
6624 if (net != &init_net)
6625 INIT_LIST_HEAD(&net->dev_base_head);
6627 net->dev_name_head = netdev_create_hash();
6628 if (net->dev_name_head == NULL)
6631 net->dev_index_head = netdev_create_hash();
6632 if (net->dev_index_head == NULL)
6638 kfree(net->dev_name_head);
6644 * netdev_drivername - network driver for the device
6645 * @dev: network device
6647 * Determine network driver for device.
6649 const char *netdev_drivername(const struct net_device *dev)
6651 const struct device_driver *driver;
6652 const struct device *parent;
6653 const char *empty = "";
6655 parent = dev->dev.parent;
6659 driver = parent->driver;
6660 if (driver && driver->name)
6661 return driver->name;
6665 static int __netdev_printk(const char *level, const struct net_device *dev,
6666 struct va_format *vaf)
6670 if (dev && dev->dev.parent) {
6671 r = dev_printk_emit(level[1] - '0',
6674 dev_driver_string(dev->dev.parent),
6675 dev_name(dev->dev.parent),
6676 netdev_name(dev), vaf);
6678 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6680 r = printk("%s(NULL net_device): %pV", level, vaf);
6686 int netdev_printk(const char *level, const struct net_device *dev,
6687 const char *format, ...)
6689 struct va_format vaf;
6693 va_start(args, format);
6698 r = __netdev_printk(level, dev, &vaf);
6704 EXPORT_SYMBOL(netdev_printk);
6706 #define define_netdev_printk_level(func, level) \
6707 int func(const struct net_device *dev, const char *fmt, ...) \
6710 struct va_format vaf; \
6713 va_start(args, fmt); \
6718 r = __netdev_printk(level, dev, &vaf); \
6724 EXPORT_SYMBOL(func);
6726 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6727 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6728 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6729 define_netdev_printk_level(netdev_err, KERN_ERR);
6730 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6731 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6732 define_netdev_printk_level(netdev_info, KERN_INFO);
6734 static void __net_exit netdev_exit(struct net *net)
6736 kfree(net->dev_name_head);
6737 kfree(net->dev_index_head);
6740 static struct pernet_operations __net_initdata netdev_net_ops = {
6741 .init = netdev_init,
6742 .exit = netdev_exit,
6745 static void __net_exit default_device_exit(struct net *net)
6747 struct net_device *dev, *aux;
6749 * Push all migratable network devices back to the
6750 * initial network namespace
6753 for_each_netdev_safe(net, dev, aux) {
6755 char fb_name[IFNAMSIZ];
6757 /* Ignore unmoveable devices (i.e. loopback) */
6758 if (dev->features & NETIF_F_NETNS_LOCAL)
6761 /* Leave virtual devices for the generic cleanup */
6762 if (dev->rtnl_link_ops)
6765 /* Push remaining network devices to init_net */
6766 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6767 err = dev_change_net_namespace(dev, &init_net, fb_name);
6769 pr_emerg("%s: failed to move %s to init_net: %d\n",
6770 __func__, dev->name, err);
6777 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6779 /* Return with the rtnl_lock held when there are no network
6780 * devices unregistering in any network namespace in net_list.
6787 prepare_to_wait(&netdev_unregistering_wq, &wait,
6788 TASK_UNINTERRUPTIBLE);
6789 unregistering = false;
6791 list_for_each_entry(net, net_list, exit_list) {
6792 if (net->dev_unreg_count > 0) {
6793 unregistering = true;
6802 finish_wait(&netdev_unregistering_wq, &wait);
6805 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6807 /* At exit all network devices most be removed from a network
6808 * namespace. Do this in the reverse order of registration.
6809 * Do this across as many network namespaces as possible to
6810 * improve batching efficiency.
6812 struct net_device *dev;
6814 LIST_HEAD(dev_kill_list);
6816 /* To prevent network device cleanup code from dereferencing
6817 * loopback devices or network devices that have been freed
6818 * wait here for all pending unregistrations to complete,
6819 * before unregistring the loopback device and allowing the
6820 * network namespace be freed.
6822 * The netdev todo list containing all network devices
6823 * unregistrations that happen in default_device_exit_batch
6824 * will run in the rtnl_unlock() at the end of
6825 * default_device_exit_batch.
6827 rtnl_lock_unregistering(net_list);
6828 list_for_each_entry(net, net_list, exit_list) {
6829 for_each_netdev_reverse(net, dev) {
6830 if (dev->rtnl_link_ops)
6831 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6833 unregister_netdevice_queue(dev, &dev_kill_list);
6836 unregister_netdevice_many(&dev_kill_list);
6837 list_del(&dev_kill_list);
6841 static struct pernet_operations __net_initdata default_device_ops = {
6842 .exit = default_device_exit,
6843 .exit_batch = default_device_exit_batch,
6847 * Initialize the DEV module. At boot time this walks the device list and
6848 * unhooks any devices that fail to initialise (normally hardware not
6849 * present) and leaves us with a valid list of present and active devices.
6854 * This is called single threaded during boot, so no need
6855 * to take the rtnl semaphore.
6857 static int __init net_dev_init(void)
6859 int i, rc = -ENOMEM;
6861 BUG_ON(!dev_boot_phase);
6863 if (dev_proc_init())
6866 if (netdev_kobject_init())
6869 INIT_LIST_HEAD(&ptype_all);
6870 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6871 INIT_LIST_HEAD(&ptype_base[i]);
6873 INIT_LIST_HEAD(&offload_base);
6875 if (register_pernet_subsys(&netdev_net_ops))
6879 * Initialise the packet receive queues.
6882 for_each_possible_cpu(i) {
6883 struct softnet_data *sd = &per_cpu(softnet_data, i);
6885 memset(sd, 0, sizeof(*sd));
6886 skb_queue_head_init(&sd->input_pkt_queue);
6887 skb_queue_head_init(&sd->process_queue);
6888 sd->completion_queue = NULL;
6889 INIT_LIST_HEAD(&sd->poll_list);
6890 sd->output_queue = NULL;
6891 sd->output_queue_tailp = &sd->output_queue;
6893 sd->csd.func = rps_trigger_softirq;
6899 sd->backlog.poll = process_backlog;
6900 sd->backlog.weight = weight_p;
6901 sd->backlog.gro_list = NULL;
6902 sd->backlog.gro_count = 0;
6904 #ifdef CONFIG_NET_FLOW_LIMIT
6905 sd->flow_limit = NULL;
6911 /* The loopback device is special if any other network devices
6912 * is present in a network namespace the loopback device must
6913 * be present. Since we now dynamically allocate and free the
6914 * loopback device ensure this invariant is maintained by
6915 * keeping the loopback device as the first device on the
6916 * list of network devices. Ensuring the loopback devices
6917 * is the first device that appears and the last network device
6920 if (register_pernet_device(&loopback_net_ops))
6923 if (register_pernet_device(&default_device_ops))
6926 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6927 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6929 hotcpu_notifier(dev_cpu_callback, 0);
6936 subsys_initcall(net_dev_init);