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;
150 static int netif_rx_internal(struct sk_buff *skb);
153 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
156 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
158 * Writers must hold the rtnl semaphore while they loop through the
159 * dev_base_head list, and hold dev_base_lock for writing when they do the
160 * actual updates. This allows pure readers to access the list even
161 * while a writer is preparing to update it.
163 * To put it another way, dev_base_lock is held for writing only to
164 * protect against pure readers; the rtnl semaphore provides the
165 * protection against other writers.
167 * See, for example usages, register_netdevice() and
168 * unregister_netdevice(), which must be called with the rtnl
171 DEFINE_RWLOCK(dev_base_lock);
172 EXPORT_SYMBOL(dev_base_lock);
174 /* protects napi_hash addition/deletion and napi_gen_id */
175 static DEFINE_SPINLOCK(napi_hash_lock);
177 static unsigned int napi_gen_id;
178 static DEFINE_HASHTABLE(napi_hash, 8);
180 static seqcount_t devnet_rename_seq;
182 static inline void dev_base_seq_inc(struct net *net)
184 while (++net->dev_base_seq == 0);
187 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
189 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
191 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
194 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
196 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
199 static inline void rps_lock(struct softnet_data *sd)
202 spin_lock(&sd->input_pkt_queue.lock);
206 static inline void rps_unlock(struct softnet_data *sd)
209 spin_unlock(&sd->input_pkt_queue.lock);
213 /* Device list insertion */
214 static void list_netdevice(struct net_device *dev)
216 struct net *net = dev_net(dev);
220 write_lock_bh(&dev_base_lock);
221 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
222 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
223 hlist_add_head_rcu(&dev->index_hlist,
224 dev_index_hash(net, dev->ifindex));
225 write_unlock_bh(&dev_base_lock);
227 dev_base_seq_inc(net);
230 /* Device list removal
231 * caller must respect a RCU grace period before freeing/reusing dev
233 static void unlist_netdevice(struct net_device *dev)
237 /* Unlink dev from the device chain */
238 write_lock_bh(&dev_base_lock);
239 list_del_rcu(&dev->dev_list);
240 hlist_del_rcu(&dev->name_hlist);
241 hlist_del_rcu(&dev->index_hlist);
242 write_unlock_bh(&dev_base_lock);
244 dev_base_seq_inc(dev_net(dev));
251 static RAW_NOTIFIER_HEAD(netdev_chain);
254 * Device drivers call our routines to queue packets here. We empty the
255 * queue in the local softnet handler.
258 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
259 EXPORT_PER_CPU_SYMBOL(softnet_data);
261 #ifdef CONFIG_LOCKDEP
263 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
264 * according to dev->type
266 static const unsigned short netdev_lock_type[] =
267 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
268 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
269 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
270 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
271 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
272 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
273 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
274 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
275 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
276 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
277 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
278 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
279 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
280 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
281 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
283 static const char *const netdev_lock_name[] =
284 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
285 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
286 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
287 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
288 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
289 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
290 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
291 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
292 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
293 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
294 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
295 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
296 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
297 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
298 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
300 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
301 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
303 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
307 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
308 if (netdev_lock_type[i] == dev_type)
310 /* the last key is used by default */
311 return ARRAY_SIZE(netdev_lock_type) - 1;
314 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
315 unsigned short dev_type)
319 i = netdev_lock_pos(dev_type);
320 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
321 netdev_lock_name[i]);
324 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
328 i = netdev_lock_pos(dev->type);
329 lockdep_set_class_and_name(&dev->addr_list_lock,
330 &netdev_addr_lock_key[i],
331 netdev_lock_name[i]);
334 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
335 unsigned short dev_type)
338 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
343 /*******************************************************************************
345 Protocol management and registration routines
347 *******************************************************************************/
350 * Add a protocol ID to the list. Now that the input handler is
351 * smarter we can dispense with all the messy stuff that used to be
354 * BEWARE!!! Protocol handlers, mangling input packets,
355 * MUST BE last in hash buckets and checking protocol handlers
356 * MUST start from promiscuous ptype_all chain in net_bh.
357 * It is true now, do not change it.
358 * Explanation follows: if protocol handler, mangling packet, will
359 * be the first on list, it is not able to sense, that packet
360 * is cloned and should be copied-on-write, so that it will
361 * change it and subsequent readers will get broken packet.
365 static inline struct list_head *ptype_head(const struct packet_type *pt)
367 if (pt->type == htons(ETH_P_ALL))
370 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
374 * dev_add_pack - add packet handler
375 * @pt: packet type declaration
377 * Add a protocol handler to the networking stack. The passed &packet_type
378 * is linked into kernel lists and may not be freed until it has been
379 * removed from the kernel lists.
381 * This call does not sleep therefore it can not
382 * guarantee all CPU's that are in middle of receiving packets
383 * will see the new packet type (until the next received packet).
386 void dev_add_pack(struct packet_type *pt)
388 struct list_head *head = ptype_head(pt);
390 spin_lock(&ptype_lock);
391 list_add_rcu(&pt->list, head);
392 spin_unlock(&ptype_lock);
394 EXPORT_SYMBOL(dev_add_pack);
397 * __dev_remove_pack - remove packet handler
398 * @pt: packet type declaration
400 * Remove a protocol handler that was previously added to the kernel
401 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
402 * from the kernel lists and can be freed or reused once this function
405 * The packet type might still be in use by receivers
406 * and must not be freed until after all the CPU's have gone
407 * through a quiescent state.
409 void __dev_remove_pack(struct packet_type *pt)
411 struct list_head *head = ptype_head(pt);
412 struct packet_type *pt1;
414 spin_lock(&ptype_lock);
416 list_for_each_entry(pt1, head, list) {
418 list_del_rcu(&pt->list);
423 pr_warn("dev_remove_pack: %p not found\n", pt);
425 spin_unlock(&ptype_lock);
427 EXPORT_SYMBOL(__dev_remove_pack);
430 * dev_remove_pack - remove packet handler
431 * @pt: packet type declaration
433 * Remove a protocol handler that was previously added to the kernel
434 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
435 * from the kernel lists and can be freed or reused once this function
438 * This call sleeps to guarantee that no CPU is looking at the packet
441 void dev_remove_pack(struct packet_type *pt)
443 __dev_remove_pack(pt);
447 EXPORT_SYMBOL(dev_remove_pack);
451 * dev_add_offload - register offload handlers
452 * @po: protocol offload declaration
454 * Add protocol offload handlers to the networking stack. The passed
455 * &proto_offload is linked into kernel lists and may not be freed until
456 * it has been removed from the kernel lists.
458 * This call does not sleep therefore it can not
459 * guarantee all CPU's that are in middle of receiving packets
460 * will see the new offload handlers (until the next received packet).
462 void dev_add_offload(struct packet_offload *po)
464 struct list_head *head = &offload_base;
466 spin_lock(&offload_lock);
467 list_add_rcu(&po->list, head);
468 spin_unlock(&offload_lock);
470 EXPORT_SYMBOL(dev_add_offload);
473 * __dev_remove_offload - remove offload handler
474 * @po: packet offload declaration
476 * Remove a protocol offload handler that was previously added to the
477 * kernel offload handlers by dev_add_offload(). The passed &offload_type
478 * is removed from the kernel lists and can be freed or reused once this
481 * The packet type might still be in use by receivers
482 * and must not be freed until after all the CPU's have gone
483 * through a quiescent state.
485 static void __dev_remove_offload(struct packet_offload *po)
487 struct list_head *head = &offload_base;
488 struct packet_offload *po1;
490 spin_lock(&offload_lock);
492 list_for_each_entry(po1, head, list) {
494 list_del_rcu(&po->list);
499 pr_warn("dev_remove_offload: %p not found\n", po);
501 spin_unlock(&offload_lock);
505 * dev_remove_offload - remove packet offload handler
506 * @po: packet offload declaration
508 * Remove a packet offload handler that was previously added to the kernel
509 * offload handlers by dev_add_offload(). The passed &offload_type is
510 * removed from the kernel lists and can be freed or reused once this
513 * This call sleeps to guarantee that no CPU is looking at the packet
516 void dev_remove_offload(struct packet_offload *po)
518 __dev_remove_offload(po);
522 EXPORT_SYMBOL(dev_remove_offload);
524 /******************************************************************************
526 Device Boot-time Settings Routines
528 *******************************************************************************/
530 /* Boot time configuration table */
531 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
534 * netdev_boot_setup_add - add new setup entry
535 * @name: name of the device
536 * @map: configured settings for the device
538 * Adds new setup entry to the dev_boot_setup list. The function
539 * returns 0 on error and 1 on success. This is a generic routine to
542 static int netdev_boot_setup_add(char *name, struct ifmap *map)
544 struct netdev_boot_setup *s;
548 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
549 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
550 memset(s[i].name, 0, sizeof(s[i].name));
551 strlcpy(s[i].name, name, IFNAMSIZ);
552 memcpy(&s[i].map, map, sizeof(s[i].map));
557 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
561 * netdev_boot_setup_check - check boot time settings
562 * @dev: the netdevice
564 * Check boot time settings for the device.
565 * The found settings are set for the device to be used
566 * later in the device probing.
567 * Returns 0 if no settings found, 1 if they are.
569 int netdev_boot_setup_check(struct net_device *dev)
571 struct netdev_boot_setup *s = dev_boot_setup;
574 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
575 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
576 !strcmp(dev->name, s[i].name)) {
577 dev->irq = s[i].map.irq;
578 dev->base_addr = s[i].map.base_addr;
579 dev->mem_start = s[i].map.mem_start;
580 dev->mem_end = s[i].map.mem_end;
586 EXPORT_SYMBOL(netdev_boot_setup_check);
590 * netdev_boot_base - get address from boot time settings
591 * @prefix: prefix for network device
592 * @unit: id for network device
594 * Check boot time settings for the base address of device.
595 * The found settings are set for the device to be used
596 * later in the device probing.
597 * Returns 0 if no settings found.
599 unsigned long netdev_boot_base(const char *prefix, int unit)
601 const struct netdev_boot_setup *s = dev_boot_setup;
605 sprintf(name, "%s%d", prefix, unit);
608 * If device already registered then return base of 1
609 * to indicate not to probe for this interface
611 if (__dev_get_by_name(&init_net, name))
614 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
615 if (!strcmp(name, s[i].name))
616 return s[i].map.base_addr;
621 * Saves at boot time configured settings for any netdevice.
623 int __init netdev_boot_setup(char *str)
628 str = get_options(str, ARRAY_SIZE(ints), ints);
633 memset(&map, 0, sizeof(map));
637 map.base_addr = ints[2];
639 map.mem_start = ints[3];
641 map.mem_end = ints[4];
643 /* Add new entry to the list */
644 return netdev_boot_setup_add(str, &map);
647 __setup("netdev=", netdev_boot_setup);
649 /*******************************************************************************
651 Device Interface Subroutines
653 *******************************************************************************/
656 * __dev_get_by_name - find a device by its name
657 * @net: the applicable net namespace
658 * @name: name to find
660 * Find an interface by name. Must be called under RTNL semaphore
661 * or @dev_base_lock. If the name is found a pointer to the device
662 * is returned. If the name is not found then %NULL is returned. The
663 * reference counters are not incremented so the caller must be
664 * careful with locks.
667 struct net_device *__dev_get_by_name(struct net *net, const char *name)
669 struct net_device *dev;
670 struct hlist_head *head = dev_name_hash(net, name);
672 hlist_for_each_entry(dev, head, name_hlist)
673 if (!strncmp(dev->name, name, IFNAMSIZ))
678 EXPORT_SYMBOL(__dev_get_by_name);
681 * dev_get_by_name_rcu - find a device by its name
682 * @net: the applicable net namespace
683 * @name: name to find
685 * Find an interface by name.
686 * If the name is found a pointer to the device is returned.
687 * If the name is not found then %NULL is returned.
688 * The reference counters are not incremented so the caller must be
689 * careful with locks. The caller must hold RCU lock.
692 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
694 struct net_device *dev;
695 struct hlist_head *head = dev_name_hash(net, name);
697 hlist_for_each_entry_rcu(dev, head, name_hlist)
698 if (!strncmp(dev->name, name, IFNAMSIZ))
703 EXPORT_SYMBOL(dev_get_by_name_rcu);
706 * dev_get_by_name - find a device by its name
707 * @net: the applicable net namespace
708 * @name: name to find
710 * Find an interface by name. This can be called from any
711 * context and does its own locking. The returned handle has
712 * the usage count incremented and the caller must use dev_put() to
713 * release it when it is no longer needed. %NULL is returned if no
714 * matching device is found.
717 struct net_device *dev_get_by_name(struct net *net, const char *name)
719 struct net_device *dev;
722 dev = dev_get_by_name_rcu(net, name);
728 EXPORT_SYMBOL(dev_get_by_name);
731 * __dev_get_by_index - find a device by its ifindex
732 * @net: the applicable net namespace
733 * @ifindex: index of device
735 * Search for an interface by index. Returns %NULL if the device
736 * is not found or a pointer to the device. The device has not
737 * had its reference counter increased so the caller must be careful
738 * about locking. The caller must hold either the RTNL semaphore
742 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
744 struct net_device *dev;
745 struct hlist_head *head = dev_index_hash(net, ifindex);
747 hlist_for_each_entry(dev, head, index_hlist)
748 if (dev->ifindex == ifindex)
753 EXPORT_SYMBOL(__dev_get_by_index);
756 * dev_get_by_index_rcu - find a device by its ifindex
757 * @net: the applicable net namespace
758 * @ifindex: index of device
760 * Search for an interface by index. Returns %NULL if the device
761 * is not found or a pointer to the device. The device has not
762 * had its reference counter increased so the caller must be careful
763 * about locking. The caller must hold RCU lock.
766 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
768 struct net_device *dev;
769 struct hlist_head *head = dev_index_hash(net, ifindex);
771 hlist_for_each_entry_rcu(dev, head, index_hlist)
772 if (dev->ifindex == ifindex)
777 EXPORT_SYMBOL(dev_get_by_index_rcu);
781 * dev_get_by_index - find a device by its ifindex
782 * @net: the applicable net namespace
783 * @ifindex: index of device
785 * Search for an interface by index. Returns NULL if the device
786 * is not found or a pointer to the device. The device returned has
787 * had a reference added and the pointer is safe until the user calls
788 * dev_put to indicate they have finished with it.
791 struct net_device *dev_get_by_index(struct net *net, int ifindex)
793 struct net_device *dev;
796 dev = dev_get_by_index_rcu(net, ifindex);
802 EXPORT_SYMBOL(dev_get_by_index);
805 * netdev_get_name - get a netdevice name, knowing its ifindex.
806 * @net: network namespace
807 * @name: a pointer to the buffer where the name will be stored.
808 * @ifindex: the ifindex of the interface to get the name from.
810 * The use of raw_seqcount_begin() and cond_resched() before
811 * retrying is required as we want to give the writers a chance
812 * to complete when CONFIG_PREEMPT is not set.
814 int netdev_get_name(struct net *net, char *name, int ifindex)
816 struct net_device *dev;
820 seq = raw_seqcount_begin(&devnet_rename_seq);
822 dev = dev_get_by_index_rcu(net, ifindex);
828 strcpy(name, dev->name);
830 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
839 * dev_getbyhwaddr_rcu - find a device by its hardware address
840 * @net: the applicable net namespace
841 * @type: media type of device
842 * @ha: hardware address
844 * Search for an interface by MAC address. Returns NULL if the device
845 * is not found or a pointer to the device.
846 * The caller must hold RCU or RTNL.
847 * The returned device has not had its ref count increased
848 * and the caller must therefore be careful about locking
852 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
855 struct net_device *dev;
857 for_each_netdev_rcu(net, dev)
858 if (dev->type == type &&
859 !memcmp(dev->dev_addr, ha, dev->addr_len))
864 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
866 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
868 struct net_device *dev;
871 for_each_netdev(net, dev)
872 if (dev->type == type)
877 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
879 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
881 struct net_device *dev, *ret = NULL;
884 for_each_netdev_rcu(net, dev)
885 if (dev->type == type) {
893 EXPORT_SYMBOL(dev_getfirstbyhwtype);
896 * dev_get_by_flags_rcu - find any device with given flags
897 * @net: the applicable net namespace
898 * @if_flags: IFF_* values
899 * @mask: bitmask of bits in if_flags to check
901 * Search for any interface with the given flags. Returns NULL if a device
902 * is not found or a pointer to the device. Must be called inside
903 * rcu_read_lock(), and result refcount is unchanged.
906 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
909 struct net_device *dev, *ret;
912 for_each_netdev_rcu(net, dev) {
913 if (((dev->flags ^ if_flags) & mask) == 0) {
920 EXPORT_SYMBOL(dev_get_by_flags_rcu);
923 * dev_valid_name - check if name is okay for network device
926 * Network device names need to be valid file names to
927 * to allow sysfs to work. We also disallow any kind of
930 bool dev_valid_name(const char *name)
934 if (strlen(name) >= IFNAMSIZ)
936 if (!strcmp(name, ".") || !strcmp(name, ".."))
940 if (*name == '/' || isspace(*name))
946 EXPORT_SYMBOL(dev_valid_name);
949 * __dev_alloc_name - allocate a name for a device
950 * @net: network namespace to allocate the device name in
951 * @name: name format string
952 * @buf: scratch buffer and result name string
954 * Passed a format string - eg "lt%d" it will try and find a suitable
955 * id. It scans list of devices to build up a free map, then chooses
956 * the first empty slot. The caller must hold the dev_base or rtnl lock
957 * while allocating the name and adding the device in order to avoid
959 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
960 * Returns the number of the unit assigned or a negative errno code.
963 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
967 const int max_netdevices = 8*PAGE_SIZE;
968 unsigned long *inuse;
969 struct net_device *d;
971 p = strnchr(name, IFNAMSIZ-1, '%');
974 * Verify the string as this thing may have come from
975 * the user. There must be either one "%d" and no other "%"
978 if (p[1] != 'd' || strchr(p + 2, '%'))
981 /* Use one page as a bit array of possible slots */
982 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
986 for_each_netdev(net, d) {
987 if (!sscanf(d->name, name, &i))
989 if (i < 0 || i >= max_netdevices)
992 /* avoid cases where sscanf is not exact inverse of printf */
993 snprintf(buf, IFNAMSIZ, name, i);
994 if (!strncmp(buf, d->name, IFNAMSIZ))
998 i = find_first_zero_bit(inuse, max_netdevices);
999 free_page((unsigned long) inuse);
1003 snprintf(buf, IFNAMSIZ, name, i);
1004 if (!__dev_get_by_name(net, buf))
1007 /* It is possible to run out of possible slots
1008 * when the name is long and there isn't enough space left
1009 * for the digits, or if all bits are used.
1015 * dev_alloc_name - allocate a name for a device
1017 * @name: name format string
1019 * Passed a format string - eg "lt%d" it will try and find a suitable
1020 * id. It scans list of devices to build up a free map, then chooses
1021 * the first empty slot. The caller must hold the dev_base or rtnl lock
1022 * while allocating the name and adding the device in order to avoid
1024 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1025 * Returns the number of the unit assigned or a negative errno code.
1028 int dev_alloc_name(struct net_device *dev, const char *name)
1034 BUG_ON(!dev_net(dev));
1036 ret = __dev_alloc_name(net, name, buf);
1038 strlcpy(dev->name, buf, IFNAMSIZ);
1041 EXPORT_SYMBOL(dev_alloc_name);
1043 static int dev_alloc_name_ns(struct net *net,
1044 struct net_device *dev,
1050 ret = __dev_alloc_name(net, name, buf);
1052 strlcpy(dev->name, buf, IFNAMSIZ);
1056 static int dev_get_valid_name(struct net *net,
1057 struct net_device *dev,
1062 if (!dev_valid_name(name))
1065 if (strchr(name, '%'))
1066 return dev_alloc_name_ns(net, dev, name);
1067 else if (__dev_get_by_name(net, name))
1069 else if (dev->name != name)
1070 strlcpy(dev->name, name, IFNAMSIZ);
1076 * dev_change_name - change name of a device
1078 * @newname: name (or format string) must be at least IFNAMSIZ
1080 * Change name of a device, can pass format strings "eth%d".
1083 int dev_change_name(struct net_device *dev, const char *newname)
1085 char oldname[IFNAMSIZ];
1091 BUG_ON(!dev_net(dev));
1094 if (dev->flags & IFF_UP)
1097 write_seqcount_begin(&devnet_rename_seq);
1099 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1100 write_seqcount_end(&devnet_rename_seq);
1104 memcpy(oldname, dev->name, IFNAMSIZ);
1106 err = dev_get_valid_name(net, dev, newname);
1108 write_seqcount_end(&devnet_rename_seq);
1113 ret = device_rename(&dev->dev, dev->name);
1115 memcpy(dev->name, oldname, IFNAMSIZ);
1116 write_seqcount_end(&devnet_rename_seq);
1120 write_seqcount_end(&devnet_rename_seq);
1122 netdev_adjacent_rename_links(dev, oldname);
1124 write_lock_bh(&dev_base_lock);
1125 hlist_del_rcu(&dev->name_hlist);
1126 write_unlock_bh(&dev_base_lock);
1130 write_lock_bh(&dev_base_lock);
1131 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1132 write_unlock_bh(&dev_base_lock);
1134 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1135 ret = notifier_to_errno(ret);
1138 /* err >= 0 after dev_alloc_name() or stores the first errno */
1141 write_seqcount_begin(&devnet_rename_seq);
1142 memcpy(dev->name, oldname, IFNAMSIZ);
1143 memcpy(oldname, newname, IFNAMSIZ);
1146 pr_err("%s: name change rollback failed: %d\n",
1155 * dev_set_alias - change ifalias of a device
1157 * @alias: name up to IFALIASZ
1158 * @len: limit of bytes to copy from info
1160 * Set ifalias for a device,
1162 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1168 if (len >= IFALIASZ)
1172 kfree(dev->ifalias);
1173 dev->ifalias = NULL;
1177 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1180 dev->ifalias = new_ifalias;
1182 strlcpy(dev->ifalias, alias, len+1);
1188 * netdev_features_change - device changes features
1189 * @dev: device to cause notification
1191 * Called to indicate a device has changed features.
1193 void netdev_features_change(struct net_device *dev)
1195 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1197 EXPORT_SYMBOL(netdev_features_change);
1200 * netdev_state_change - device changes state
1201 * @dev: device to cause notification
1203 * Called to indicate a device has changed state. This function calls
1204 * the notifier chains for netdev_chain and sends a NEWLINK message
1205 * to the routing socket.
1207 void netdev_state_change(struct net_device *dev)
1209 if (dev->flags & IFF_UP) {
1210 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1211 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1214 EXPORT_SYMBOL(netdev_state_change);
1217 * netdev_notify_peers - notify network peers about existence of @dev
1218 * @dev: network device
1220 * Generate traffic such that interested network peers are aware of
1221 * @dev, such as by generating a gratuitous ARP. This may be used when
1222 * a device wants to inform the rest of the network about some sort of
1223 * reconfiguration such as a failover event or virtual machine
1226 void netdev_notify_peers(struct net_device *dev)
1229 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1232 EXPORT_SYMBOL(netdev_notify_peers);
1234 static int __dev_open(struct net_device *dev)
1236 const struct net_device_ops *ops = dev->netdev_ops;
1241 if (!netif_device_present(dev))
1244 /* Block netpoll from trying to do any rx path servicing.
1245 * If we don't do this there is a chance ndo_poll_controller
1246 * or ndo_poll may be running while we open the device
1248 netpoll_poll_disable(dev);
1250 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1251 ret = notifier_to_errno(ret);
1255 set_bit(__LINK_STATE_START, &dev->state);
1257 if (ops->ndo_validate_addr)
1258 ret = ops->ndo_validate_addr(dev);
1260 if (!ret && ops->ndo_open)
1261 ret = ops->ndo_open(dev);
1263 netpoll_poll_enable(dev);
1266 clear_bit(__LINK_STATE_START, &dev->state);
1268 dev->flags |= IFF_UP;
1269 net_dmaengine_get();
1270 dev_set_rx_mode(dev);
1272 add_device_randomness(dev->dev_addr, dev->addr_len);
1279 * dev_open - prepare an interface for use.
1280 * @dev: device to open
1282 * Takes a device from down to up state. The device's private open
1283 * function is invoked and then the multicast lists are loaded. Finally
1284 * the device is moved into the up state and a %NETDEV_UP message is
1285 * sent to the netdev notifier chain.
1287 * Calling this function on an active interface is a nop. On a failure
1288 * a negative errno code is returned.
1290 int dev_open(struct net_device *dev)
1294 if (dev->flags & IFF_UP)
1297 ret = __dev_open(dev);
1301 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1302 call_netdevice_notifiers(NETDEV_UP, dev);
1306 EXPORT_SYMBOL(dev_open);
1308 static int __dev_close_many(struct list_head *head)
1310 struct net_device *dev;
1315 list_for_each_entry(dev, head, close_list) {
1316 /* Temporarily disable netpoll until the interface is down */
1317 netpoll_poll_disable(dev);
1319 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1321 clear_bit(__LINK_STATE_START, &dev->state);
1323 /* Synchronize to scheduled poll. We cannot touch poll list, it
1324 * can be even on different cpu. So just clear netif_running().
1326 * dev->stop() will invoke napi_disable() on all of it's
1327 * napi_struct instances on this device.
1329 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1332 dev_deactivate_many(head);
1334 list_for_each_entry(dev, head, close_list) {
1335 const struct net_device_ops *ops = dev->netdev_ops;
1338 * Call the device specific close. This cannot fail.
1339 * Only if device is UP
1341 * We allow it to be called even after a DETACH hot-plug
1347 dev->flags &= ~IFF_UP;
1348 net_dmaengine_put();
1349 netpoll_poll_enable(dev);
1355 static int __dev_close(struct net_device *dev)
1360 list_add(&dev->close_list, &single);
1361 retval = __dev_close_many(&single);
1367 static int dev_close_many(struct list_head *head)
1369 struct net_device *dev, *tmp;
1371 /* Remove the devices that don't need to be closed */
1372 list_for_each_entry_safe(dev, tmp, head, close_list)
1373 if (!(dev->flags & IFF_UP))
1374 list_del_init(&dev->close_list);
1376 __dev_close_many(head);
1378 list_for_each_entry_safe(dev, tmp, head, close_list) {
1379 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1380 call_netdevice_notifiers(NETDEV_DOWN, dev);
1381 list_del_init(&dev->close_list);
1388 * dev_close - shutdown an interface.
1389 * @dev: device to shutdown
1391 * This function moves an active device into down state. A
1392 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1393 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1396 int dev_close(struct net_device *dev)
1398 if (dev->flags & IFF_UP) {
1401 list_add(&dev->close_list, &single);
1402 dev_close_many(&single);
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 bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
1647 if (!(dev->flags & IFF_UP))
1650 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1651 if (skb->len <= len)
1654 /* if TSO is enabled, we don't care about the length as the packet
1655 * could be forwarded without being segmented before
1657 if (skb_is_gso(skb))
1662 EXPORT_SYMBOL_GPL(is_skb_forwardable);
1664 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1666 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1667 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1668 atomic_long_inc(&dev->rx_dropped);
1674 if (unlikely(!is_skb_forwardable(dev, skb))) {
1675 atomic_long_inc(&dev->rx_dropped);
1680 skb_scrub_packet(skb, true);
1681 skb->protocol = eth_type_trans(skb, dev);
1685 EXPORT_SYMBOL_GPL(__dev_forward_skb);
1688 * dev_forward_skb - loopback an skb to another netif
1690 * @dev: destination network device
1691 * @skb: buffer to forward
1694 * NET_RX_SUCCESS (no congestion)
1695 * NET_RX_DROP (packet was dropped, but freed)
1697 * dev_forward_skb can be used for injecting an skb from the
1698 * start_xmit function of one device into the receive queue
1699 * of another device.
1701 * The receiving device may be in another namespace, so
1702 * we have to clear all information in the skb that could
1703 * impact namespace isolation.
1705 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1707 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1709 EXPORT_SYMBOL_GPL(dev_forward_skb);
1711 static inline int deliver_skb(struct sk_buff *skb,
1712 struct packet_type *pt_prev,
1713 struct net_device *orig_dev)
1715 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1717 atomic_inc(&skb->users);
1718 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1721 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1723 if (!ptype->af_packet_priv || !skb->sk)
1726 if (ptype->id_match)
1727 return ptype->id_match(ptype, skb->sk);
1728 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1735 * Support routine. Sends outgoing frames to any network
1736 * taps currently in use.
1739 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1741 struct packet_type *ptype;
1742 struct sk_buff *skb2 = NULL;
1743 struct packet_type *pt_prev = NULL;
1746 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1747 /* Never send packets back to the socket
1748 * they originated from - MvS (miquels@drinkel.ow.org)
1750 if ((ptype->dev == dev || !ptype->dev) &&
1751 (!skb_loop_sk(ptype, skb))) {
1753 deliver_skb(skb2, pt_prev, skb->dev);
1758 skb2 = skb_clone(skb, GFP_ATOMIC);
1762 net_timestamp_set(skb2);
1764 /* skb->nh should be correctly
1765 set by sender, so that the second statement is
1766 just protection against buggy protocols.
1768 skb_reset_mac_header(skb2);
1770 if (skb_network_header(skb2) < skb2->data ||
1771 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1772 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1773 ntohs(skb2->protocol),
1775 skb_reset_network_header(skb2);
1778 skb2->transport_header = skb2->network_header;
1779 skb2->pkt_type = PACKET_OUTGOING;
1784 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1789 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1790 * @dev: Network device
1791 * @txq: number of queues available
1793 * If real_num_tx_queues is changed the tc mappings may no longer be
1794 * valid. To resolve this verify the tc mapping remains valid and if
1795 * not NULL the mapping. With no priorities mapping to this
1796 * offset/count pair it will no longer be used. In the worst case TC0
1797 * is invalid nothing can be done so disable priority mappings. If is
1798 * expected that drivers will fix this mapping if they can before
1799 * calling netif_set_real_num_tx_queues.
1801 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1804 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1806 /* If TC0 is invalidated disable TC mapping */
1807 if (tc->offset + tc->count > txq) {
1808 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1813 /* Invalidated prio to tc mappings set to TC0 */
1814 for (i = 1; i < TC_BITMASK + 1; i++) {
1815 int q = netdev_get_prio_tc_map(dev, i);
1817 tc = &dev->tc_to_txq[q];
1818 if (tc->offset + tc->count > txq) {
1819 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1821 netdev_set_prio_tc_map(dev, i, 0);
1827 static DEFINE_MUTEX(xps_map_mutex);
1828 #define xmap_dereference(P) \
1829 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1831 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1834 struct xps_map *map = NULL;
1838 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1840 for (pos = 0; map && pos < map->len; pos++) {
1841 if (map->queues[pos] == index) {
1843 map->queues[pos] = map->queues[--map->len];
1845 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1846 kfree_rcu(map, rcu);
1856 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1858 struct xps_dev_maps *dev_maps;
1860 bool active = false;
1862 mutex_lock(&xps_map_mutex);
1863 dev_maps = xmap_dereference(dev->xps_maps);
1868 for_each_possible_cpu(cpu) {
1869 for (i = index; i < dev->num_tx_queues; i++) {
1870 if (!remove_xps_queue(dev_maps, cpu, i))
1873 if (i == dev->num_tx_queues)
1878 RCU_INIT_POINTER(dev->xps_maps, NULL);
1879 kfree_rcu(dev_maps, rcu);
1882 for (i = index; i < dev->num_tx_queues; i++)
1883 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1887 mutex_unlock(&xps_map_mutex);
1890 static struct xps_map *expand_xps_map(struct xps_map *map,
1893 struct xps_map *new_map;
1894 int alloc_len = XPS_MIN_MAP_ALLOC;
1897 for (pos = 0; map && pos < map->len; pos++) {
1898 if (map->queues[pos] != index)
1903 /* Need to add queue to this CPU's existing map */
1905 if (pos < map->alloc_len)
1908 alloc_len = map->alloc_len * 2;
1911 /* Need to allocate new map to store queue on this CPU's map */
1912 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1917 for (i = 0; i < pos; i++)
1918 new_map->queues[i] = map->queues[i];
1919 new_map->alloc_len = alloc_len;
1925 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1928 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1929 struct xps_map *map, *new_map;
1930 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1931 int cpu, numa_node_id = -2;
1932 bool active = false;
1934 mutex_lock(&xps_map_mutex);
1936 dev_maps = xmap_dereference(dev->xps_maps);
1938 /* allocate memory for queue storage */
1939 for_each_online_cpu(cpu) {
1940 if (!cpumask_test_cpu(cpu, mask))
1944 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1945 if (!new_dev_maps) {
1946 mutex_unlock(&xps_map_mutex);
1950 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1953 map = expand_xps_map(map, cpu, index);
1957 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1961 goto out_no_new_maps;
1963 for_each_possible_cpu(cpu) {
1964 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1965 /* add queue to CPU maps */
1968 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1969 while ((pos < map->len) && (map->queues[pos] != index))
1972 if (pos == map->len)
1973 map->queues[map->len++] = index;
1975 if (numa_node_id == -2)
1976 numa_node_id = cpu_to_node(cpu);
1977 else if (numa_node_id != cpu_to_node(cpu))
1980 } else if (dev_maps) {
1981 /* fill in the new device map from the old device map */
1982 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1983 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1988 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1990 /* Cleanup old maps */
1992 for_each_possible_cpu(cpu) {
1993 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1994 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1995 if (map && map != new_map)
1996 kfree_rcu(map, rcu);
1999 kfree_rcu(dev_maps, rcu);
2002 dev_maps = new_dev_maps;
2006 /* update Tx queue numa node */
2007 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2008 (numa_node_id >= 0) ? numa_node_id :
2014 /* removes queue from unused CPUs */
2015 for_each_possible_cpu(cpu) {
2016 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2019 if (remove_xps_queue(dev_maps, cpu, index))
2023 /* free map if not active */
2025 RCU_INIT_POINTER(dev->xps_maps, NULL);
2026 kfree_rcu(dev_maps, rcu);
2030 mutex_unlock(&xps_map_mutex);
2034 /* remove any maps that we added */
2035 for_each_possible_cpu(cpu) {
2036 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2037 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2039 if (new_map && new_map != map)
2043 mutex_unlock(&xps_map_mutex);
2045 kfree(new_dev_maps);
2048 EXPORT_SYMBOL(netif_set_xps_queue);
2052 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2053 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2055 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2059 if (txq < 1 || txq > dev->num_tx_queues)
2062 if (dev->reg_state == NETREG_REGISTERED ||
2063 dev->reg_state == NETREG_UNREGISTERING) {
2066 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2072 netif_setup_tc(dev, txq);
2074 if (txq < dev->real_num_tx_queues) {
2075 qdisc_reset_all_tx_gt(dev, txq);
2077 netif_reset_xps_queues_gt(dev, txq);
2082 dev->real_num_tx_queues = txq;
2085 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2089 * netif_set_real_num_rx_queues - set actual number of RX queues used
2090 * @dev: Network device
2091 * @rxq: Actual number of RX queues
2093 * This must be called either with the rtnl_lock held or before
2094 * registration of the net device. Returns 0 on success, or a
2095 * negative error code. If called before registration, it always
2098 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2102 if (rxq < 1 || rxq > dev->num_rx_queues)
2105 if (dev->reg_state == NETREG_REGISTERED) {
2108 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2114 dev->real_num_rx_queues = rxq;
2117 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2121 * netif_get_num_default_rss_queues - default number of RSS queues
2123 * This routine should set an upper limit on the number of RSS queues
2124 * used by default by multiqueue devices.
2126 int netif_get_num_default_rss_queues(void)
2128 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2130 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2132 static inline void __netif_reschedule(struct Qdisc *q)
2134 struct softnet_data *sd;
2135 unsigned long flags;
2137 local_irq_save(flags);
2138 sd = &__get_cpu_var(softnet_data);
2139 q->next_sched = NULL;
2140 *sd->output_queue_tailp = q;
2141 sd->output_queue_tailp = &q->next_sched;
2142 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2143 local_irq_restore(flags);
2146 void __netif_schedule(struct Qdisc *q)
2148 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2149 __netif_reschedule(q);
2151 EXPORT_SYMBOL(__netif_schedule);
2153 struct dev_kfree_skb_cb {
2154 enum skb_free_reason reason;
2157 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2159 return (struct dev_kfree_skb_cb *)skb->cb;
2162 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2164 unsigned long flags;
2166 if (likely(atomic_read(&skb->users) == 1)) {
2168 atomic_set(&skb->users, 0);
2169 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2172 get_kfree_skb_cb(skb)->reason = reason;
2173 local_irq_save(flags);
2174 skb->next = __this_cpu_read(softnet_data.completion_queue);
2175 __this_cpu_write(softnet_data.completion_queue, skb);
2176 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2177 local_irq_restore(flags);
2179 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2181 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2183 if (in_irq() || irqs_disabled())
2184 __dev_kfree_skb_irq(skb, reason);
2188 EXPORT_SYMBOL(__dev_kfree_skb_any);
2192 * netif_device_detach - mark device as removed
2193 * @dev: network device
2195 * Mark device as removed from system and therefore no longer available.
2197 void netif_device_detach(struct net_device *dev)
2199 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2200 netif_running(dev)) {
2201 netif_tx_stop_all_queues(dev);
2204 EXPORT_SYMBOL(netif_device_detach);
2207 * netif_device_attach - mark device as attached
2208 * @dev: network device
2210 * Mark device as attached from system and restart if needed.
2212 void netif_device_attach(struct net_device *dev)
2214 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2215 netif_running(dev)) {
2216 netif_tx_wake_all_queues(dev);
2217 __netdev_watchdog_up(dev);
2220 EXPORT_SYMBOL(netif_device_attach);
2222 static void skb_warn_bad_offload(const struct sk_buff *skb)
2224 static const netdev_features_t null_features = 0;
2225 struct net_device *dev = skb->dev;
2226 const char *driver = "";
2228 if (!net_ratelimit())
2231 if (dev && dev->dev.parent)
2232 driver = dev_driver_string(dev->dev.parent);
2234 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2235 "gso_type=%d ip_summed=%d\n",
2236 driver, dev ? &dev->features : &null_features,
2237 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2238 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2239 skb_shinfo(skb)->gso_type, skb->ip_summed);
2243 * Invalidate hardware checksum when packet is to be mangled, and
2244 * complete checksum manually on outgoing path.
2246 int skb_checksum_help(struct sk_buff *skb)
2249 int ret = 0, offset;
2251 if (skb->ip_summed == CHECKSUM_COMPLETE)
2252 goto out_set_summed;
2254 if (unlikely(skb_shinfo(skb)->gso_size)) {
2255 skb_warn_bad_offload(skb);
2259 /* Before computing a checksum, we should make sure no frag could
2260 * be modified by an external entity : checksum could be wrong.
2262 if (skb_has_shared_frag(skb)) {
2263 ret = __skb_linearize(skb);
2268 offset = skb_checksum_start_offset(skb);
2269 BUG_ON(offset >= skb_headlen(skb));
2270 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2272 offset += skb->csum_offset;
2273 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2275 if (skb_cloned(skb) &&
2276 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2277 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2282 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2284 skb->ip_summed = CHECKSUM_NONE;
2288 EXPORT_SYMBOL(skb_checksum_help);
2290 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2292 __be16 type = skb->protocol;
2293 int vlan_depth = skb->mac_len;
2295 /* Tunnel gso handlers can set protocol to ethernet. */
2296 if (type == htons(ETH_P_TEB)) {
2299 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2302 eth = (struct ethhdr *)skb_mac_header(skb);
2303 type = eth->h_proto;
2306 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2307 struct vlan_hdr *vh;
2309 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2312 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2313 type = vh->h_vlan_encapsulated_proto;
2314 vlan_depth += VLAN_HLEN;
2317 *depth = vlan_depth;
2323 * skb_mac_gso_segment - mac layer segmentation handler.
2324 * @skb: buffer to segment
2325 * @features: features for the output path (see dev->features)
2327 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2328 netdev_features_t features)
2330 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2331 struct packet_offload *ptype;
2332 int vlan_depth = skb->mac_len;
2333 __be16 type = skb_network_protocol(skb, &vlan_depth);
2335 if (unlikely(!type))
2336 return ERR_PTR(-EINVAL);
2338 __skb_pull(skb, vlan_depth);
2341 list_for_each_entry_rcu(ptype, &offload_base, list) {
2342 if (ptype->type == type && ptype->callbacks.gso_segment) {
2343 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2346 err = ptype->callbacks.gso_send_check(skb);
2347 segs = ERR_PTR(err);
2348 if (err || skb_gso_ok(skb, features))
2350 __skb_push(skb, (skb->data -
2351 skb_network_header(skb)));
2353 segs = ptype->callbacks.gso_segment(skb, features);
2359 __skb_push(skb, skb->data - skb_mac_header(skb));
2363 EXPORT_SYMBOL(skb_mac_gso_segment);
2366 /* openvswitch calls this on rx path, so we need a different check.
2368 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2371 return skb->ip_summed != CHECKSUM_PARTIAL;
2373 return skb->ip_summed == CHECKSUM_NONE;
2377 * __skb_gso_segment - Perform segmentation on skb.
2378 * @skb: buffer to segment
2379 * @features: features for the output path (see dev->features)
2380 * @tx_path: whether it is called in TX path
2382 * This function segments the given skb and returns a list of segments.
2384 * It may return NULL if the skb requires no segmentation. This is
2385 * only possible when GSO is used for verifying header integrity.
2387 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2388 netdev_features_t features, bool tx_path)
2390 if (unlikely(skb_needs_check(skb, tx_path))) {
2393 skb_warn_bad_offload(skb);
2395 if (skb_header_cloned(skb) &&
2396 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2397 return ERR_PTR(err);
2400 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2401 SKB_GSO_CB(skb)->encap_level = 0;
2403 skb_reset_mac_header(skb);
2404 skb_reset_mac_len(skb);
2406 return skb_mac_gso_segment(skb, features);
2408 EXPORT_SYMBOL(__skb_gso_segment);
2410 /* Take action when hardware reception checksum errors are detected. */
2412 void netdev_rx_csum_fault(struct net_device *dev)
2414 if (net_ratelimit()) {
2415 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2419 EXPORT_SYMBOL(netdev_rx_csum_fault);
2422 /* Actually, we should eliminate this check as soon as we know, that:
2423 * 1. IOMMU is present and allows to map all the memory.
2424 * 2. No high memory really exists on this machine.
2427 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2429 #ifdef CONFIG_HIGHMEM
2431 if (!(dev->features & NETIF_F_HIGHDMA)) {
2432 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2433 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2434 if (PageHighMem(skb_frag_page(frag)))
2439 if (PCI_DMA_BUS_IS_PHYS) {
2440 struct device *pdev = dev->dev.parent;
2444 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2445 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2446 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2447 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2456 void (*destructor)(struct sk_buff *skb);
2459 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2461 static void dev_gso_skb_destructor(struct sk_buff *skb)
2463 struct dev_gso_cb *cb;
2465 kfree_skb_list(skb->next);
2468 cb = DEV_GSO_CB(skb);
2470 cb->destructor(skb);
2474 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2475 * @skb: buffer to segment
2476 * @features: device features as applicable to this skb
2478 * This function segments the given skb and stores the list of segments
2481 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2483 struct sk_buff *segs;
2485 segs = skb_gso_segment(skb, features);
2487 /* Verifying header integrity only. */
2492 return PTR_ERR(segs);
2495 DEV_GSO_CB(skb)->destructor = skb->destructor;
2496 skb->destructor = dev_gso_skb_destructor;
2501 static netdev_features_t harmonize_features(struct sk_buff *skb,
2502 netdev_features_t features)
2506 if (skb->ip_summed != CHECKSUM_NONE &&
2507 !can_checksum_protocol(features, skb_network_protocol(skb, &tmp))) {
2508 features &= ~NETIF_F_ALL_CSUM;
2509 } else if (illegal_highdma(skb->dev, skb)) {
2510 features &= ~NETIF_F_SG;
2516 netdev_features_t netif_skb_features(struct sk_buff *skb)
2518 __be16 protocol = skb->protocol;
2519 netdev_features_t features = skb->dev->features;
2521 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2522 features &= ~NETIF_F_GSO_MASK;
2524 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2525 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2526 protocol = veh->h_vlan_encapsulated_proto;
2527 } else if (!vlan_tx_tag_present(skb)) {
2528 return harmonize_features(skb, features);
2531 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2532 NETIF_F_HW_VLAN_STAG_TX);
2534 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2535 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2536 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2537 NETIF_F_HW_VLAN_STAG_TX;
2539 return harmonize_features(skb, features);
2541 EXPORT_SYMBOL(netif_skb_features);
2543 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2544 struct netdev_queue *txq)
2546 const struct net_device_ops *ops = dev->netdev_ops;
2547 int rc = NETDEV_TX_OK;
2548 unsigned int skb_len;
2550 if (likely(!skb->next)) {
2551 netdev_features_t features;
2554 * If device doesn't need skb->dst, release it right now while
2555 * its hot in this cpu cache
2557 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2560 features = netif_skb_features(skb);
2562 if (vlan_tx_tag_present(skb) &&
2563 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2564 skb = __vlan_put_tag(skb, skb->vlan_proto,
2565 vlan_tx_tag_get(skb));
2572 /* If encapsulation offload request, verify we are testing
2573 * hardware encapsulation features instead of standard
2574 * features for the netdev
2576 if (skb->encapsulation)
2577 features &= dev->hw_enc_features;
2579 if (netif_needs_gso(skb, features)) {
2580 if (unlikely(dev_gso_segment(skb, features)))
2585 if (skb_needs_linearize(skb, features) &&
2586 __skb_linearize(skb))
2589 /* If packet is not checksummed and device does not
2590 * support checksumming for this protocol, complete
2591 * checksumming here.
2593 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2594 if (skb->encapsulation)
2595 skb_set_inner_transport_header(skb,
2596 skb_checksum_start_offset(skb));
2598 skb_set_transport_header(skb,
2599 skb_checksum_start_offset(skb));
2600 if (!(features & NETIF_F_ALL_CSUM) &&
2601 skb_checksum_help(skb))
2606 if (!list_empty(&ptype_all))
2607 dev_queue_xmit_nit(skb, dev);
2610 trace_net_dev_start_xmit(skb, dev);
2611 rc = ops->ndo_start_xmit(skb, dev);
2612 trace_net_dev_xmit(skb, rc, dev, skb_len);
2613 if (rc == NETDEV_TX_OK)
2614 txq_trans_update(txq);
2620 struct sk_buff *nskb = skb->next;
2622 skb->next = nskb->next;
2625 if (!list_empty(&ptype_all))
2626 dev_queue_xmit_nit(nskb, dev);
2628 skb_len = nskb->len;
2629 trace_net_dev_start_xmit(nskb, dev);
2630 rc = ops->ndo_start_xmit(nskb, dev);
2631 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2632 if (unlikely(rc != NETDEV_TX_OK)) {
2633 if (rc & ~NETDEV_TX_MASK)
2634 goto out_kfree_gso_skb;
2635 nskb->next = skb->next;
2639 txq_trans_update(txq);
2640 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2641 return NETDEV_TX_BUSY;
2642 } while (skb->next);
2645 if (likely(skb->next == NULL)) {
2646 skb->destructor = DEV_GSO_CB(skb)->destructor;
2655 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2657 static void qdisc_pkt_len_init(struct sk_buff *skb)
2659 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2661 qdisc_skb_cb(skb)->pkt_len = skb->len;
2663 /* To get more precise estimation of bytes sent on wire,
2664 * we add to pkt_len the headers size of all segments
2666 if (shinfo->gso_size) {
2667 unsigned int hdr_len;
2668 u16 gso_segs = shinfo->gso_segs;
2670 /* mac layer + network layer */
2671 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2673 /* + transport layer */
2674 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2675 hdr_len += tcp_hdrlen(skb);
2677 hdr_len += sizeof(struct udphdr);
2679 if (shinfo->gso_type & SKB_GSO_DODGY)
2680 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2683 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2687 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2688 struct net_device *dev,
2689 struct netdev_queue *txq)
2691 spinlock_t *root_lock = qdisc_lock(q);
2695 qdisc_pkt_len_init(skb);
2696 qdisc_calculate_pkt_len(skb, q);
2698 * Heuristic to force contended enqueues to serialize on a
2699 * separate lock before trying to get qdisc main lock.
2700 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2701 * and dequeue packets faster.
2703 contended = qdisc_is_running(q);
2704 if (unlikely(contended))
2705 spin_lock(&q->busylock);
2707 spin_lock(root_lock);
2708 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2711 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2712 qdisc_run_begin(q)) {
2714 * This is a work-conserving queue; there are no old skbs
2715 * waiting to be sent out; and the qdisc is not running -
2716 * xmit the skb directly.
2718 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2721 qdisc_bstats_update(q, skb);
2723 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2724 if (unlikely(contended)) {
2725 spin_unlock(&q->busylock);
2732 rc = NET_XMIT_SUCCESS;
2735 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2736 if (qdisc_run_begin(q)) {
2737 if (unlikely(contended)) {
2738 spin_unlock(&q->busylock);
2744 spin_unlock(root_lock);
2745 if (unlikely(contended))
2746 spin_unlock(&q->busylock);
2750 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2751 static void skb_update_prio(struct sk_buff *skb)
2753 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2755 if (!skb->priority && skb->sk && map) {
2756 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2758 if (prioidx < map->priomap_len)
2759 skb->priority = map->priomap[prioidx];
2763 #define skb_update_prio(skb)
2766 static DEFINE_PER_CPU(int, xmit_recursion);
2767 #define RECURSION_LIMIT 10
2770 * dev_loopback_xmit - loop back @skb
2771 * @skb: buffer to transmit
2773 int dev_loopback_xmit(struct sk_buff *skb)
2775 skb_reset_mac_header(skb);
2776 __skb_pull(skb, skb_network_offset(skb));
2777 skb->pkt_type = PACKET_LOOPBACK;
2778 skb->ip_summed = CHECKSUM_UNNECESSARY;
2779 WARN_ON(!skb_dst(skb));
2784 EXPORT_SYMBOL(dev_loopback_xmit);
2787 * __dev_queue_xmit - transmit a buffer
2788 * @skb: buffer to transmit
2789 * @accel_priv: private data used for L2 forwarding offload
2791 * Queue a buffer for transmission to a network device. The caller must
2792 * have set the device and priority and built the buffer before calling
2793 * this function. The function can be called from an interrupt.
2795 * A negative errno code is returned on a failure. A success does not
2796 * guarantee the frame will be transmitted as it may be dropped due
2797 * to congestion or traffic shaping.
2799 * -----------------------------------------------------------------------------------
2800 * I notice this method can also return errors from the queue disciplines,
2801 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2804 * Regardless of the return value, the skb is consumed, so it is currently
2805 * difficult to retry a send to this method. (You can bump the ref count
2806 * before sending to hold a reference for retry if you are careful.)
2808 * When calling this method, interrupts MUST be enabled. This is because
2809 * the BH enable code must have IRQs enabled so that it will not deadlock.
2812 static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
2814 struct net_device *dev = skb->dev;
2815 struct netdev_queue *txq;
2819 skb_reset_mac_header(skb);
2821 /* Disable soft irqs for various locks below. Also
2822 * stops preemption for RCU.
2826 skb_update_prio(skb);
2828 txq = netdev_pick_tx(dev, skb, accel_priv);
2829 q = rcu_dereference_bh(txq->qdisc);
2831 #ifdef CONFIG_NET_CLS_ACT
2832 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2834 trace_net_dev_queue(skb);
2836 rc = __dev_xmit_skb(skb, q, dev, txq);
2840 /* The device has no queue. Common case for software devices:
2841 loopback, all the sorts of tunnels...
2843 Really, it is unlikely that netif_tx_lock protection is necessary
2844 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2846 However, it is possible, that they rely on protection
2849 Check this and shot the lock. It is not prone from deadlocks.
2850 Either shot noqueue qdisc, it is even simpler 8)
2852 if (dev->flags & IFF_UP) {
2853 int cpu = smp_processor_id(); /* ok because BHs are off */
2855 if (txq->xmit_lock_owner != cpu) {
2857 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2858 goto recursion_alert;
2860 HARD_TX_LOCK(dev, txq, cpu);
2862 if (!netif_xmit_stopped(txq)) {
2863 __this_cpu_inc(xmit_recursion);
2864 rc = dev_hard_start_xmit(skb, dev, txq);
2865 __this_cpu_dec(xmit_recursion);
2866 if (dev_xmit_complete(rc)) {
2867 HARD_TX_UNLOCK(dev, txq);
2871 HARD_TX_UNLOCK(dev, txq);
2872 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2875 /* Recursion is detected! It is possible,
2879 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2885 rcu_read_unlock_bh();
2887 atomic_long_inc(&dev->tx_dropped);
2891 rcu_read_unlock_bh();
2895 int dev_queue_xmit(struct sk_buff *skb)
2897 return __dev_queue_xmit(skb, NULL);
2899 EXPORT_SYMBOL(dev_queue_xmit);
2901 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2903 return __dev_queue_xmit(skb, accel_priv);
2905 EXPORT_SYMBOL(dev_queue_xmit_accel);
2908 /*=======================================================================
2910 =======================================================================*/
2912 int netdev_max_backlog __read_mostly = 1000;
2913 EXPORT_SYMBOL(netdev_max_backlog);
2915 int netdev_tstamp_prequeue __read_mostly = 1;
2916 int netdev_budget __read_mostly = 300;
2917 int weight_p __read_mostly = 64; /* old backlog weight */
2919 /* Called with irq disabled */
2920 static inline void ____napi_schedule(struct softnet_data *sd,
2921 struct napi_struct *napi)
2923 list_add_tail(&napi->poll_list, &sd->poll_list);
2924 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2929 /* One global table that all flow-based protocols share. */
2930 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2931 EXPORT_SYMBOL(rps_sock_flow_table);
2933 struct static_key rps_needed __read_mostly;
2935 static struct rps_dev_flow *
2936 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2937 struct rps_dev_flow *rflow, u16 next_cpu)
2939 if (next_cpu != RPS_NO_CPU) {
2940 #ifdef CONFIG_RFS_ACCEL
2941 struct netdev_rx_queue *rxqueue;
2942 struct rps_dev_flow_table *flow_table;
2943 struct rps_dev_flow *old_rflow;
2948 /* Should we steer this flow to a different hardware queue? */
2949 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2950 !(dev->features & NETIF_F_NTUPLE))
2952 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2953 if (rxq_index == skb_get_rx_queue(skb))
2956 rxqueue = dev->_rx + rxq_index;
2957 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2960 flow_id = skb_get_hash(skb) & flow_table->mask;
2961 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2962 rxq_index, flow_id);
2966 rflow = &flow_table->flows[flow_id];
2968 if (old_rflow->filter == rflow->filter)
2969 old_rflow->filter = RPS_NO_FILTER;
2973 per_cpu(softnet_data, next_cpu).input_queue_head;
2976 rflow->cpu = next_cpu;
2981 * get_rps_cpu is called from netif_receive_skb and returns the target
2982 * CPU from the RPS map of the receiving queue for a given skb.
2983 * rcu_read_lock must be held on entry.
2985 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2986 struct rps_dev_flow **rflowp)
2988 struct netdev_rx_queue *rxqueue;
2989 struct rps_map *map;
2990 struct rps_dev_flow_table *flow_table;
2991 struct rps_sock_flow_table *sock_flow_table;
2996 if (skb_rx_queue_recorded(skb)) {
2997 u16 index = skb_get_rx_queue(skb);
2998 if (unlikely(index >= dev->real_num_rx_queues)) {
2999 WARN_ONCE(dev->real_num_rx_queues > 1,
3000 "%s received packet on queue %u, but number "
3001 "of RX queues is %u\n",
3002 dev->name, index, dev->real_num_rx_queues);
3005 rxqueue = dev->_rx + index;
3009 map = rcu_dereference(rxqueue->rps_map);
3011 if (map->len == 1 &&
3012 !rcu_access_pointer(rxqueue->rps_flow_table)) {
3013 tcpu = map->cpus[0];
3014 if (cpu_online(tcpu))
3018 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3022 skb_reset_network_header(skb);
3023 hash = skb_get_hash(skb);
3027 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3028 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3029 if (flow_table && sock_flow_table) {
3031 struct rps_dev_flow *rflow;
3033 rflow = &flow_table->flows[hash & flow_table->mask];
3036 next_cpu = sock_flow_table->ents[hash & sock_flow_table->mask];
3039 * If the desired CPU (where last recvmsg was done) is
3040 * different from current CPU (one in the rx-queue flow
3041 * table entry), switch if one of the following holds:
3042 * - Current CPU is unset (equal to RPS_NO_CPU).
3043 * - Current CPU is offline.
3044 * - The current CPU's queue tail has advanced beyond the
3045 * last packet that was enqueued using this table entry.
3046 * This guarantees that all previous packets for the flow
3047 * have been dequeued, thus preserving in order delivery.
3049 if (unlikely(tcpu != next_cpu) &&
3050 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3051 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3052 rflow->last_qtail)) >= 0)) {
3054 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3057 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3065 tcpu = map->cpus[((u64) hash * map->len) >> 32];
3067 if (cpu_online(tcpu)) {
3077 #ifdef CONFIG_RFS_ACCEL
3080 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3081 * @dev: Device on which the filter was set
3082 * @rxq_index: RX queue index
3083 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3084 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3086 * Drivers that implement ndo_rx_flow_steer() should periodically call
3087 * this function for each installed filter and remove the filters for
3088 * which it returns %true.
3090 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3091 u32 flow_id, u16 filter_id)
3093 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3094 struct rps_dev_flow_table *flow_table;
3095 struct rps_dev_flow *rflow;
3100 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3101 if (flow_table && flow_id <= flow_table->mask) {
3102 rflow = &flow_table->flows[flow_id];
3103 cpu = ACCESS_ONCE(rflow->cpu);
3104 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3105 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3106 rflow->last_qtail) <
3107 (int)(10 * flow_table->mask)))
3113 EXPORT_SYMBOL(rps_may_expire_flow);
3115 #endif /* CONFIG_RFS_ACCEL */
3117 /* Called from hardirq (IPI) context */
3118 static void rps_trigger_softirq(void *data)
3120 struct softnet_data *sd = data;
3122 ____napi_schedule(sd, &sd->backlog);
3126 #endif /* CONFIG_RPS */
3129 * Check if this softnet_data structure is another cpu one
3130 * If yes, queue it to our IPI list and return 1
3133 static int rps_ipi_queued(struct softnet_data *sd)
3136 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3139 sd->rps_ipi_next = mysd->rps_ipi_list;
3140 mysd->rps_ipi_list = sd;
3142 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3145 #endif /* CONFIG_RPS */
3149 #ifdef CONFIG_NET_FLOW_LIMIT
3150 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3153 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3155 #ifdef CONFIG_NET_FLOW_LIMIT
3156 struct sd_flow_limit *fl;
3157 struct softnet_data *sd;
3158 unsigned int old_flow, new_flow;
3160 if (qlen < (netdev_max_backlog >> 1))
3163 sd = &__get_cpu_var(softnet_data);
3166 fl = rcu_dereference(sd->flow_limit);
3168 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3169 old_flow = fl->history[fl->history_head];
3170 fl->history[fl->history_head] = new_flow;
3173 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3175 if (likely(fl->buckets[old_flow]))
3176 fl->buckets[old_flow]--;
3178 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3190 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3191 * queue (may be a remote CPU queue).
3193 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3194 unsigned int *qtail)
3196 struct softnet_data *sd;
3197 unsigned long flags;
3200 sd = &per_cpu(softnet_data, cpu);
3202 local_irq_save(flags);
3205 qlen = skb_queue_len(&sd->input_pkt_queue);
3206 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3207 if (skb_queue_len(&sd->input_pkt_queue)) {
3209 __skb_queue_tail(&sd->input_pkt_queue, skb);
3210 input_queue_tail_incr_save(sd, qtail);
3212 local_irq_restore(flags);
3213 return NET_RX_SUCCESS;
3216 /* Schedule NAPI for backlog device
3217 * We can use non atomic operation since we own the queue lock
3219 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3220 if (!rps_ipi_queued(sd))
3221 ____napi_schedule(sd, &sd->backlog);
3229 local_irq_restore(flags);
3231 atomic_long_inc(&skb->dev->rx_dropped);
3236 static int netif_rx_internal(struct sk_buff *skb)
3240 net_timestamp_check(netdev_tstamp_prequeue, skb);
3242 trace_netif_rx(skb);
3244 if (static_key_false(&rps_needed)) {
3245 struct rps_dev_flow voidflow, *rflow = &voidflow;
3251 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3253 cpu = smp_processor_id();
3255 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3263 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3270 * netif_rx - post buffer to the network code
3271 * @skb: buffer to post
3273 * This function receives a packet from a device driver and queues it for
3274 * the upper (protocol) levels to process. It always succeeds. The buffer
3275 * may be dropped during processing for congestion control or by the
3279 * NET_RX_SUCCESS (no congestion)
3280 * NET_RX_DROP (packet was dropped)
3284 int netif_rx(struct sk_buff *skb)
3286 trace_netif_rx_entry(skb);
3288 return netif_rx_internal(skb);
3290 EXPORT_SYMBOL(netif_rx);
3292 int netif_rx_ni(struct sk_buff *skb)
3296 trace_netif_rx_ni_entry(skb);
3299 err = netif_rx_internal(skb);
3300 if (local_softirq_pending())
3306 EXPORT_SYMBOL(netif_rx_ni);
3308 static void net_tx_action(struct softirq_action *h)
3310 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3312 if (sd->completion_queue) {
3313 struct sk_buff *clist;
3315 local_irq_disable();
3316 clist = sd->completion_queue;
3317 sd->completion_queue = NULL;
3321 struct sk_buff *skb = clist;
3322 clist = clist->next;
3324 WARN_ON(atomic_read(&skb->users));
3325 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3326 trace_consume_skb(skb);
3328 trace_kfree_skb(skb, net_tx_action);
3333 if (sd->output_queue) {
3336 local_irq_disable();
3337 head = sd->output_queue;
3338 sd->output_queue = NULL;
3339 sd->output_queue_tailp = &sd->output_queue;
3343 struct Qdisc *q = head;
3344 spinlock_t *root_lock;
3346 head = head->next_sched;
3348 root_lock = qdisc_lock(q);
3349 if (spin_trylock(root_lock)) {
3350 smp_mb__before_clear_bit();
3351 clear_bit(__QDISC_STATE_SCHED,
3354 spin_unlock(root_lock);
3356 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3358 __netif_reschedule(q);
3360 smp_mb__before_clear_bit();
3361 clear_bit(__QDISC_STATE_SCHED,
3369 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3370 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3371 /* This hook is defined here for ATM LANE */
3372 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3373 unsigned char *addr) __read_mostly;
3374 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3377 #ifdef CONFIG_NET_CLS_ACT
3378 /* TODO: Maybe we should just force sch_ingress to be compiled in
3379 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3380 * a compare and 2 stores extra right now if we dont have it on
3381 * but have CONFIG_NET_CLS_ACT
3382 * NOTE: This doesn't stop any functionality; if you dont have
3383 * the ingress scheduler, you just can't add policies on ingress.
3386 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3388 struct net_device *dev = skb->dev;
3389 u32 ttl = G_TC_RTTL(skb->tc_verd);
3390 int result = TC_ACT_OK;
3393 if (unlikely(MAX_RED_LOOP < ttl++)) {
3394 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3395 skb->skb_iif, dev->ifindex);
3399 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3400 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3403 if (q != &noop_qdisc) {
3404 spin_lock(qdisc_lock(q));
3405 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3406 result = qdisc_enqueue_root(skb, q);
3407 spin_unlock(qdisc_lock(q));
3413 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3414 struct packet_type **pt_prev,
3415 int *ret, struct net_device *orig_dev)
3417 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3419 if (!rxq || rxq->qdisc == &noop_qdisc)
3423 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3427 switch (ing_filter(skb, rxq)) {
3441 * netdev_rx_handler_register - register receive handler
3442 * @dev: device to register a handler for
3443 * @rx_handler: receive handler to register
3444 * @rx_handler_data: data pointer that is used by rx handler
3446 * Register a receive handler for a device. This handler will then be
3447 * called from __netif_receive_skb. A negative errno code is returned
3450 * The caller must hold the rtnl_mutex.
3452 * For a general description of rx_handler, see enum rx_handler_result.
3454 int netdev_rx_handler_register(struct net_device *dev,
3455 rx_handler_func_t *rx_handler,
3456 void *rx_handler_data)
3460 if (dev->rx_handler)
3463 /* Note: rx_handler_data must be set before rx_handler */
3464 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3465 rcu_assign_pointer(dev->rx_handler, rx_handler);
3469 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3472 * netdev_rx_handler_unregister - unregister receive handler
3473 * @dev: device to unregister a handler from
3475 * Unregister a receive handler from a device.
3477 * The caller must hold the rtnl_mutex.
3479 void netdev_rx_handler_unregister(struct net_device *dev)
3483 RCU_INIT_POINTER(dev->rx_handler, NULL);
3484 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3485 * section has a guarantee to see a non NULL rx_handler_data
3489 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3491 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3494 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3495 * the special handling of PFMEMALLOC skbs.
3497 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3499 switch (skb->protocol) {
3500 case htons(ETH_P_ARP):
3501 case htons(ETH_P_IP):
3502 case htons(ETH_P_IPV6):
3503 case htons(ETH_P_8021Q):
3504 case htons(ETH_P_8021AD):
3511 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3513 struct packet_type *ptype, *pt_prev;
3514 rx_handler_func_t *rx_handler;
3515 struct net_device *orig_dev;
3516 struct net_device *null_or_dev;
3517 bool deliver_exact = false;
3518 int ret = NET_RX_DROP;
3521 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3523 trace_netif_receive_skb(skb);
3525 orig_dev = skb->dev;
3527 skb_reset_network_header(skb);
3528 if (!skb_transport_header_was_set(skb))
3529 skb_reset_transport_header(skb);
3530 skb_reset_mac_len(skb);
3537 skb->skb_iif = skb->dev->ifindex;
3539 __this_cpu_inc(softnet_data.processed);
3541 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3542 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3543 skb = vlan_untag(skb);
3548 #ifdef CONFIG_NET_CLS_ACT
3549 if (skb->tc_verd & TC_NCLS) {
3550 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3558 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3559 if (!ptype->dev || ptype->dev == skb->dev) {
3561 ret = deliver_skb(skb, pt_prev, orig_dev);
3567 #ifdef CONFIG_NET_CLS_ACT
3568 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3574 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3577 if (vlan_tx_tag_present(skb)) {
3579 ret = deliver_skb(skb, pt_prev, orig_dev);
3582 if (vlan_do_receive(&skb))
3584 else if (unlikely(!skb))
3588 rx_handler = rcu_dereference(skb->dev->rx_handler);
3591 ret = deliver_skb(skb, pt_prev, orig_dev);
3594 switch (rx_handler(&skb)) {
3595 case RX_HANDLER_CONSUMED:
3596 ret = NET_RX_SUCCESS;
3598 case RX_HANDLER_ANOTHER:
3600 case RX_HANDLER_EXACT:
3601 deliver_exact = true;
3602 case RX_HANDLER_PASS:
3609 if (unlikely(vlan_tx_tag_present(skb))) {
3610 if (vlan_tx_tag_get_id(skb))
3611 skb->pkt_type = PACKET_OTHERHOST;
3612 /* Note: we might in the future use prio bits
3613 * and set skb->priority like in vlan_do_receive()
3614 * For the time being, just ignore Priority Code Point
3619 /* deliver only exact match when indicated */
3620 null_or_dev = deliver_exact ? skb->dev : NULL;
3622 type = skb->protocol;
3623 list_for_each_entry_rcu(ptype,
3624 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3625 if (ptype->type == type &&
3626 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3627 ptype->dev == orig_dev)) {
3629 ret = deliver_skb(skb, pt_prev, orig_dev);
3635 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3638 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3641 atomic_long_inc(&skb->dev->rx_dropped);
3643 /* Jamal, now you will not able to escape explaining
3644 * me how you were going to use this. :-)
3654 static int __netif_receive_skb(struct sk_buff *skb)
3658 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3659 unsigned long pflags = current->flags;
3662 * PFMEMALLOC skbs are special, they should
3663 * - be delivered to SOCK_MEMALLOC sockets only
3664 * - stay away from userspace
3665 * - have bounded memory usage
3667 * Use PF_MEMALLOC as this saves us from propagating the allocation
3668 * context down to all allocation sites.
3670 current->flags |= PF_MEMALLOC;
3671 ret = __netif_receive_skb_core(skb, true);
3672 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3674 ret = __netif_receive_skb_core(skb, false);
3679 static int netif_receive_skb_internal(struct sk_buff *skb)
3681 net_timestamp_check(netdev_tstamp_prequeue, skb);
3683 if (skb_defer_rx_timestamp(skb))
3684 return NET_RX_SUCCESS;
3687 if (static_key_false(&rps_needed)) {
3688 struct rps_dev_flow voidflow, *rflow = &voidflow;
3693 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3696 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3703 return __netif_receive_skb(skb);
3707 * netif_receive_skb - process receive buffer from network
3708 * @skb: buffer to process
3710 * netif_receive_skb() is the main receive data processing function.
3711 * It always succeeds. The buffer may be dropped during processing
3712 * for congestion control or by the protocol layers.
3714 * This function may only be called from softirq context and interrupts
3715 * should be enabled.
3717 * Return values (usually ignored):
3718 * NET_RX_SUCCESS: no congestion
3719 * NET_RX_DROP: packet was dropped
3721 int netif_receive_skb(struct sk_buff *skb)
3723 trace_netif_receive_skb_entry(skb);
3725 return netif_receive_skb_internal(skb);
3727 EXPORT_SYMBOL(netif_receive_skb);
3729 /* Network device is going away, flush any packets still pending
3730 * Called with irqs disabled.
3732 static void flush_backlog(void *arg)
3734 struct net_device *dev = arg;
3735 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3736 struct sk_buff *skb, *tmp;
3739 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3740 if (skb->dev == dev) {
3741 __skb_unlink(skb, &sd->input_pkt_queue);
3743 input_queue_head_incr(sd);
3748 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3749 if (skb->dev == dev) {
3750 __skb_unlink(skb, &sd->process_queue);
3752 input_queue_head_incr(sd);
3757 static int napi_gro_complete(struct sk_buff *skb)
3759 struct packet_offload *ptype;
3760 __be16 type = skb->protocol;
3761 struct list_head *head = &offload_base;
3764 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3766 if (NAPI_GRO_CB(skb)->count == 1) {
3767 skb_shinfo(skb)->gso_size = 0;
3772 list_for_each_entry_rcu(ptype, head, list) {
3773 if (ptype->type != type || !ptype->callbacks.gro_complete)
3776 err = ptype->callbacks.gro_complete(skb, 0);
3782 WARN_ON(&ptype->list == head);
3784 return NET_RX_SUCCESS;
3788 return netif_receive_skb_internal(skb);
3791 /* napi->gro_list contains packets ordered by age.
3792 * youngest packets at the head of it.
3793 * Complete skbs in reverse order to reduce latencies.
3795 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3797 struct sk_buff *skb, *prev = NULL;
3799 /* scan list and build reverse chain */
3800 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3805 for (skb = prev; skb; skb = prev) {
3808 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3812 napi_gro_complete(skb);
3816 napi->gro_list = NULL;
3818 EXPORT_SYMBOL(napi_gro_flush);
3820 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3823 unsigned int maclen = skb->dev->hard_header_len;
3824 u32 hash = skb_get_hash_raw(skb);
3826 for (p = napi->gro_list; p; p = p->next) {
3827 unsigned long diffs;
3829 NAPI_GRO_CB(p)->flush = 0;
3831 if (hash != skb_get_hash_raw(p)) {
3832 NAPI_GRO_CB(p)->same_flow = 0;
3836 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3837 diffs |= p->vlan_tci ^ skb->vlan_tci;
3838 if (maclen == ETH_HLEN)
3839 diffs |= compare_ether_header(skb_mac_header(p),
3840 skb_mac_header(skb));
3842 diffs = memcmp(skb_mac_header(p),
3843 skb_mac_header(skb),
3845 NAPI_GRO_CB(p)->same_flow = !diffs;
3849 static void skb_gro_reset_offset(struct sk_buff *skb)
3851 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3852 const skb_frag_t *frag0 = &pinfo->frags[0];
3854 NAPI_GRO_CB(skb)->data_offset = 0;
3855 NAPI_GRO_CB(skb)->frag0 = NULL;
3856 NAPI_GRO_CB(skb)->frag0_len = 0;
3858 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3860 !PageHighMem(skb_frag_page(frag0))) {
3861 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3862 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3866 static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
3868 struct skb_shared_info *pinfo = skb_shinfo(skb);
3870 BUG_ON(skb->end - skb->tail < grow);
3872 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3874 skb->data_len -= grow;
3877 pinfo->frags[0].page_offset += grow;
3878 skb_frag_size_sub(&pinfo->frags[0], grow);
3880 if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
3881 skb_frag_unref(skb, 0);
3882 memmove(pinfo->frags, pinfo->frags + 1,
3883 --pinfo->nr_frags * sizeof(pinfo->frags[0]));
3887 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3889 struct sk_buff **pp = NULL;
3890 struct packet_offload *ptype;
3891 __be16 type = skb->protocol;
3892 struct list_head *head = &offload_base;
3894 enum gro_result ret;
3897 if (!(skb->dev->features & NETIF_F_GRO))
3900 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3903 gro_list_prepare(napi, skb);
3904 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3907 list_for_each_entry_rcu(ptype, head, list) {
3908 if (ptype->type != type || !ptype->callbacks.gro_receive)
3911 skb_set_network_header(skb, skb_gro_offset(skb));
3912 skb_reset_mac_len(skb);
3913 NAPI_GRO_CB(skb)->same_flow = 0;
3914 NAPI_GRO_CB(skb)->flush = 0;
3915 NAPI_GRO_CB(skb)->free = 0;
3916 NAPI_GRO_CB(skb)->udp_mark = 0;
3918 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3923 if (&ptype->list == head)
3926 same_flow = NAPI_GRO_CB(skb)->same_flow;
3927 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3930 struct sk_buff *nskb = *pp;
3934 napi_gro_complete(nskb);
3941 if (NAPI_GRO_CB(skb)->flush)
3944 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
3945 struct sk_buff *nskb = napi->gro_list;
3947 /* locate the end of the list to select the 'oldest' flow */
3948 while (nskb->next) {
3954 napi_gro_complete(nskb);
3958 NAPI_GRO_CB(skb)->count = 1;
3959 NAPI_GRO_CB(skb)->age = jiffies;
3960 NAPI_GRO_CB(skb)->last = skb;
3961 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3962 skb->next = napi->gro_list;
3963 napi->gro_list = skb;
3967 grow = skb_gro_offset(skb) - skb_headlen(skb);
3969 gro_pull_from_frag0(skb, grow);
3978 struct packet_offload *gro_find_receive_by_type(__be16 type)
3980 struct list_head *offload_head = &offload_base;
3981 struct packet_offload *ptype;
3983 list_for_each_entry_rcu(ptype, offload_head, list) {
3984 if (ptype->type != type || !ptype->callbacks.gro_receive)
3990 EXPORT_SYMBOL(gro_find_receive_by_type);
3992 struct packet_offload *gro_find_complete_by_type(__be16 type)
3994 struct list_head *offload_head = &offload_base;
3995 struct packet_offload *ptype;
3997 list_for_each_entry_rcu(ptype, offload_head, list) {
3998 if (ptype->type != type || !ptype->callbacks.gro_complete)
4004 EXPORT_SYMBOL(gro_find_complete_by_type);
4006 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4010 if (netif_receive_skb_internal(skb))
4018 case GRO_MERGED_FREE:
4019 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
4020 kmem_cache_free(skbuff_head_cache, skb);
4033 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4035 trace_napi_gro_receive_entry(skb);
4037 skb_gro_reset_offset(skb);
4039 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4041 EXPORT_SYMBOL(napi_gro_receive);
4043 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4045 __skb_pull(skb, skb_headlen(skb));
4046 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4047 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4049 skb->dev = napi->dev;
4051 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4056 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4058 struct sk_buff *skb = napi->skb;
4061 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4066 EXPORT_SYMBOL(napi_get_frags);
4068 static gro_result_t napi_frags_finish(struct napi_struct *napi,
4069 struct sk_buff *skb,
4075 __skb_push(skb, ETH_HLEN);
4076 skb->protocol = eth_type_trans(skb, skb->dev);
4077 if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4082 case GRO_MERGED_FREE:
4083 napi_reuse_skb(napi, skb);
4093 /* Upper GRO stack assumes network header starts at gro_offset=0
4094 * Drivers could call both napi_gro_frags() and napi_gro_receive()
4095 * We copy ethernet header into skb->data to have a common layout.
4097 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4099 struct sk_buff *skb = napi->skb;
4100 const struct ethhdr *eth;
4101 unsigned int hlen = sizeof(*eth);
4105 skb_reset_mac_header(skb);
4106 skb_gro_reset_offset(skb);
4108 eth = skb_gro_header_fast(skb, 0);
4109 if (unlikely(skb_gro_header_hard(skb, hlen))) {
4110 eth = skb_gro_header_slow(skb, hlen, 0);
4111 if (unlikely(!eth)) {
4112 napi_reuse_skb(napi, skb);
4116 gro_pull_from_frag0(skb, hlen);
4117 NAPI_GRO_CB(skb)->frag0 += hlen;
4118 NAPI_GRO_CB(skb)->frag0_len -= hlen;
4120 __skb_pull(skb, hlen);
4123 * This works because the only protocols we care about don't require
4125 * We'll fix it up properly in napi_frags_finish()
4127 skb->protocol = eth->h_proto;
4132 gro_result_t napi_gro_frags(struct napi_struct *napi)
4134 struct sk_buff *skb = napi_frags_skb(napi);
4139 trace_napi_gro_frags_entry(skb);
4141 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4143 EXPORT_SYMBOL(napi_gro_frags);
4146 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4147 * Note: called with local irq disabled, but exits with local irq enabled.
4149 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4152 struct softnet_data *remsd = sd->rps_ipi_list;
4155 sd->rps_ipi_list = NULL;
4159 /* Send pending IPI's to kick RPS processing on remote cpus. */
4161 struct softnet_data *next = remsd->rps_ipi_next;
4163 if (cpu_online(remsd->cpu))
4164 smp_call_function_single_async(remsd->cpu,
4173 static int process_backlog(struct napi_struct *napi, int quota)
4176 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4179 /* Check if we have pending ipi, its better to send them now,
4180 * not waiting net_rx_action() end.
4182 if (sd->rps_ipi_list) {
4183 local_irq_disable();
4184 net_rps_action_and_irq_enable(sd);
4187 napi->weight = weight_p;
4188 local_irq_disable();
4189 while (work < quota) {
4190 struct sk_buff *skb;
4193 while ((skb = __skb_dequeue(&sd->process_queue))) {
4195 __netif_receive_skb(skb);
4196 local_irq_disable();
4197 input_queue_head_incr(sd);
4198 if (++work >= quota) {
4205 qlen = skb_queue_len(&sd->input_pkt_queue);
4207 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4208 &sd->process_queue);
4210 if (qlen < quota - work) {
4212 * Inline a custom version of __napi_complete().
4213 * only current cpu owns and manipulates this napi,
4214 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4215 * we can use a plain write instead of clear_bit(),
4216 * and we dont need an smp_mb() memory barrier.
4218 list_del(&napi->poll_list);
4221 quota = work + qlen;
4231 * __napi_schedule - schedule for receive
4232 * @n: entry to schedule
4234 * The entry's receive function will be scheduled to run
4236 void __napi_schedule(struct napi_struct *n)
4238 unsigned long flags;
4240 local_irq_save(flags);
4241 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4242 local_irq_restore(flags);
4244 EXPORT_SYMBOL(__napi_schedule);
4246 void __napi_complete(struct napi_struct *n)
4248 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4249 BUG_ON(n->gro_list);
4251 list_del(&n->poll_list);
4252 smp_mb__before_clear_bit();
4253 clear_bit(NAPI_STATE_SCHED, &n->state);
4255 EXPORT_SYMBOL(__napi_complete);
4257 void napi_complete(struct napi_struct *n)
4259 unsigned long flags;
4262 * don't let napi dequeue from the cpu poll list
4263 * just in case its running on a different cpu
4265 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4268 napi_gro_flush(n, false);
4269 local_irq_save(flags);
4271 local_irq_restore(flags);
4273 EXPORT_SYMBOL(napi_complete);
4275 /* must be called under rcu_read_lock(), as we dont take a reference */
4276 struct napi_struct *napi_by_id(unsigned int napi_id)
4278 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4279 struct napi_struct *napi;
4281 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4282 if (napi->napi_id == napi_id)
4287 EXPORT_SYMBOL_GPL(napi_by_id);
4289 void napi_hash_add(struct napi_struct *napi)
4291 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4293 spin_lock(&napi_hash_lock);
4295 /* 0 is not a valid id, we also skip an id that is taken
4296 * we expect both events to be extremely rare
4299 while (!napi->napi_id) {
4300 napi->napi_id = ++napi_gen_id;
4301 if (napi_by_id(napi->napi_id))
4305 hlist_add_head_rcu(&napi->napi_hash_node,
4306 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4308 spin_unlock(&napi_hash_lock);
4311 EXPORT_SYMBOL_GPL(napi_hash_add);
4313 /* Warning : caller is responsible to make sure rcu grace period
4314 * is respected before freeing memory containing @napi
4316 void napi_hash_del(struct napi_struct *napi)
4318 spin_lock(&napi_hash_lock);
4320 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4321 hlist_del_rcu(&napi->napi_hash_node);
4323 spin_unlock(&napi_hash_lock);
4325 EXPORT_SYMBOL_GPL(napi_hash_del);
4327 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4328 int (*poll)(struct napi_struct *, int), int weight)
4330 INIT_LIST_HEAD(&napi->poll_list);
4331 napi->gro_count = 0;
4332 napi->gro_list = NULL;
4335 if (weight > NAPI_POLL_WEIGHT)
4336 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4338 napi->weight = weight;
4339 list_add(&napi->dev_list, &dev->napi_list);
4341 #ifdef CONFIG_NETPOLL
4342 spin_lock_init(&napi->poll_lock);
4343 napi->poll_owner = -1;
4345 set_bit(NAPI_STATE_SCHED, &napi->state);
4347 EXPORT_SYMBOL(netif_napi_add);
4349 void netif_napi_del(struct napi_struct *napi)
4351 list_del_init(&napi->dev_list);
4352 napi_free_frags(napi);
4354 kfree_skb_list(napi->gro_list);
4355 napi->gro_list = NULL;
4356 napi->gro_count = 0;
4358 EXPORT_SYMBOL(netif_napi_del);
4360 static void net_rx_action(struct softirq_action *h)
4362 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4363 unsigned long time_limit = jiffies + 2;
4364 int budget = netdev_budget;
4367 local_irq_disable();
4369 while (!list_empty(&sd->poll_list)) {
4370 struct napi_struct *n;
4373 /* If softirq window is exhuasted then punt.
4374 * Allow this to run for 2 jiffies since which will allow
4375 * an average latency of 1.5/HZ.
4377 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4382 /* Even though interrupts have been re-enabled, this
4383 * access is safe because interrupts can only add new
4384 * entries to the tail of this list, and only ->poll()
4385 * calls can remove this head entry from the list.
4387 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4389 have = netpoll_poll_lock(n);
4393 /* This NAPI_STATE_SCHED test is for avoiding a race
4394 * with netpoll's poll_napi(). Only the entity which
4395 * obtains the lock and sees NAPI_STATE_SCHED set will
4396 * actually make the ->poll() call. Therefore we avoid
4397 * accidentally calling ->poll() when NAPI is not scheduled.
4400 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4401 work = n->poll(n, weight);
4405 WARN_ON_ONCE(work > weight);
4409 local_irq_disable();
4411 /* Drivers must not modify the NAPI state if they
4412 * consume the entire weight. In such cases this code
4413 * still "owns" the NAPI instance and therefore can
4414 * move the instance around on the list at-will.
4416 if (unlikely(work == weight)) {
4417 if (unlikely(napi_disable_pending(n))) {
4420 local_irq_disable();
4423 /* flush too old packets
4424 * If HZ < 1000, flush all packets.
4427 napi_gro_flush(n, HZ >= 1000);
4428 local_irq_disable();
4430 list_move_tail(&n->poll_list, &sd->poll_list);
4434 netpoll_poll_unlock(have);
4437 net_rps_action_and_irq_enable(sd);
4439 #ifdef CONFIG_NET_DMA
4441 * There may not be any more sk_buffs coming right now, so push
4442 * any pending DMA copies to hardware
4444 dma_issue_pending_all();
4451 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4455 struct netdev_adjacent {
4456 struct net_device *dev;
4458 /* upper master flag, there can only be one master device per list */
4461 /* counter for the number of times this device was added to us */
4464 /* private field for the users */
4467 struct list_head list;
4468 struct rcu_head rcu;
4471 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4472 struct net_device *adj_dev,
4473 struct list_head *adj_list)
4475 struct netdev_adjacent *adj;
4477 list_for_each_entry(adj, adj_list, list) {
4478 if (adj->dev == adj_dev)
4485 * netdev_has_upper_dev - Check if device is linked to an upper device
4487 * @upper_dev: upper device to check
4489 * Find out if a device is linked to specified upper device and return true
4490 * in case it is. Note that this checks only immediate upper device,
4491 * not through a complete stack of devices. The caller must hold the RTNL lock.
4493 bool netdev_has_upper_dev(struct net_device *dev,
4494 struct net_device *upper_dev)
4498 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4500 EXPORT_SYMBOL(netdev_has_upper_dev);
4503 * netdev_has_any_upper_dev - Check if device is linked to some device
4506 * Find out if a device is linked to an upper device and return true in case
4507 * it is. The caller must hold the RTNL lock.
4509 static bool netdev_has_any_upper_dev(struct net_device *dev)
4513 return !list_empty(&dev->all_adj_list.upper);
4517 * netdev_master_upper_dev_get - Get master upper device
4520 * Find a master upper device and return pointer to it or NULL in case
4521 * it's not there. The caller must hold the RTNL lock.
4523 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4525 struct netdev_adjacent *upper;
4529 if (list_empty(&dev->adj_list.upper))
4532 upper = list_first_entry(&dev->adj_list.upper,
4533 struct netdev_adjacent, list);
4534 if (likely(upper->master))
4538 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4540 void *netdev_adjacent_get_private(struct list_head *adj_list)
4542 struct netdev_adjacent *adj;
4544 adj = list_entry(adj_list, struct netdev_adjacent, list);
4546 return adj->private;
4548 EXPORT_SYMBOL(netdev_adjacent_get_private);
4551 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
4553 * @iter: list_head ** of the current position
4555 * Gets the next device from the dev's upper list, starting from iter
4556 * position. The caller must hold RCU read lock.
4558 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
4559 struct list_head **iter)
4561 struct netdev_adjacent *upper;
4563 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4565 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4567 if (&upper->list == &dev->adj_list.upper)
4570 *iter = &upper->list;
4574 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
4577 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4579 * @iter: list_head ** of the current position
4581 * Gets the next device from the dev's upper list, starting from iter
4582 * position. The caller must hold RCU read lock.
4584 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4585 struct list_head **iter)
4587 struct netdev_adjacent *upper;
4589 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4591 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4593 if (&upper->list == &dev->all_adj_list.upper)
4596 *iter = &upper->list;
4600 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4603 * netdev_lower_get_next_private - Get the next ->private from the
4604 * lower neighbour list
4606 * @iter: list_head ** of the current position
4608 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4609 * list, starting from iter position. The caller must hold either hold the
4610 * RTNL lock or its own locking that guarantees that the neighbour lower
4611 * list will remain unchainged.
4613 void *netdev_lower_get_next_private(struct net_device *dev,
4614 struct list_head **iter)
4616 struct netdev_adjacent *lower;
4618 lower = list_entry(*iter, struct netdev_adjacent, list);
4620 if (&lower->list == &dev->adj_list.lower)
4623 *iter = lower->list.next;
4625 return lower->private;
4627 EXPORT_SYMBOL(netdev_lower_get_next_private);
4630 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4631 * lower neighbour list, RCU
4634 * @iter: list_head ** of the current position
4636 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4637 * list, starting from iter position. The caller must hold RCU read lock.
4639 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4640 struct list_head **iter)
4642 struct netdev_adjacent *lower;
4644 WARN_ON_ONCE(!rcu_read_lock_held());
4646 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4648 if (&lower->list == &dev->adj_list.lower)
4651 *iter = &lower->list;
4653 return lower->private;
4655 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4658 * netdev_lower_get_next - Get the next device from the lower neighbour
4661 * @iter: list_head ** of the current position
4663 * Gets the next netdev_adjacent from the dev's lower neighbour
4664 * list, starting from iter position. The caller must hold RTNL lock or
4665 * its own locking that guarantees that the neighbour lower
4666 * list will remain unchainged.
4668 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
4670 struct netdev_adjacent *lower;
4672 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
4674 if (&lower->list == &dev->adj_list.lower)
4677 *iter = &lower->list;
4681 EXPORT_SYMBOL(netdev_lower_get_next);
4684 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4685 * lower neighbour list, RCU
4689 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4690 * list. The caller must hold RCU read lock.
4692 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4694 struct netdev_adjacent *lower;
4696 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4697 struct netdev_adjacent, list);
4699 return lower->private;
4702 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4705 * netdev_master_upper_dev_get_rcu - Get master upper device
4708 * Find a master upper device and return pointer to it or NULL in case
4709 * it's not there. The caller must hold the RCU read lock.
4711 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4713 struct netdev_adjacent *upper;
4715 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4716 struct netdev_adjacent, list);
4717 if (upper && likely(upper->master))
4721 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4723 static int netdev_adjacent_sysfs_add(struct net_device *dev,
4724 struct net_device *adj_dev,
4725 struct list_head *dev_list)
4727 char linkname[IFNAMSIZ+7];
4728 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4729 "upper_%s" : "lower_%s", adj_dev->name);
4730 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
4733 static void netdev_adjacent_sysfs_del(struct net_device *dev,
4735 struct list_head *dev_list)
4737 char linkname[IFNAMSIZ+7];
4738 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4739 "upper_%s" : "lower_%s", name);
4740 sysfs_remove_link(&(dev->dev.kobj), linkname);
4743 #define netdev_adjacent_is_neigh_list(dev, dev_list) \
4744 (dev_list == &dev->adj_list.upper || \
4745 dev_list == &dev->adj_list.lower)
4747 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4748 struct net_device *adj_dev,
4749 struct list_head *dev_list,
4750 void *private, bool master)
4752 struct netdev_adjacent *adj;
4755 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4762 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4767 adj->master = master;
4769 adj->private = private;
4772 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4773 adj_dev->name, dev->name, adj_dev->name);
4775 if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
4776 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
4781 /* Ensure that master link is always the first item in list. */
4783 ret = sysfs_create_link(&(dev->dev.kobj),
4784 &(adj_dev->dev.kobj), "master");
4786 goto remove_symlinks;
4788 list_add_rcu(&adj->list, dev_list);
4790 list_add_tail_rcu(&adj->list, dev_list);
4796 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4797 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4805 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4806 struct net_device *adj_dev,
4807 struct list_head *dev_list)
4809 struct netdev_adjacent *adj;
4811 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4814 pr_err("tried to remove device %s from %s\n",
4815 dev->name, adj_dev->name);
4819 if (adj->ref_nr > 1) {
4820 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4827 sysfs_remove_link(&(dev->dev.kobj), "master");
4829 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4830 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4832 list_del_rcu(&adj->list);
4833 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4834 adj_dev->name, dev->name, adj_dev->name);
4836 kfree_rcu(adj, rcu);
4839 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4840 struct net_device *upper_dev,
4841 struct list_head *up_list,
4842 struct list_head *down_list,
4843 void *private, bool master)
4847 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4852 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4855 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4862 static int __netdev_adjacent_dev_link(struct net_device *dev,
4863 struct net_device *upper_dev)
4865 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4866 &dev->all_adj_list.upper,
4867 &upper_dev->all_adj_list.lower,
4871 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4872 struct net_device *upper_dev,
4873 struct list_head *up_list,
4874 struct list_head *down_list)
4876 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4877 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4880 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4881 struct net_device *upper_dev)
4883 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4884 &dev->all_adj_list.upper,
4885 &upper_dev->all_adj_list.lower);
4888 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4889 struct net_device *upper_dev,
4890 void *private, bool master)
4892 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4897 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4898 &dev->adj_list.upper,
4899 &upper_dev->adj_list.lower,
4902 __netdev_adjacent_dev_unlink(dev, upper_dev);
4909 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4910 struct net_device *upper_dev)
4912 __netdev_adjacent_dev_unlink(dev, upper_dev);
4913 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4914 &dev->adj_list.upper,
4915 &upper_dev->adj_list.lower);
4918 static int __netdev_upper_dev_link(struct net_device *dev,
4919 struct net_device *upper_dev, bool master,
4922 struct netdev_adjacent *i, *j, *to_i, *to_j;
4927 if (dev == upper_dev)
4930 /* To prevent loops, check if dev is not upper device to upper_dev. */
4931 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4934 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4937 if (master && netdev_master_upper_dev_get(dev))
4940 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4945 /* Now that we linked these devs, make all the upper_dev's
4946 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4947 * versa, and don't forget the devices itself. All of these
4948 * links are non-neighbours.
4950 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4951 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4952 pr_debug("Interlinking %s with %s, non-neighbour\n",
4953 i->dev->name, j->dev->name);
4954 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4960 /* add dev to every upper_dev's upper device */
4961 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4962 pr_debug("linking %s's upper device %s with %s\n",
4963 upper_dev->name, i->dev->name, dev->name);
4964 ret = __netdev_adjacent_dev_link(dev, i->dev);
4966 goto rollback_upper_mesh;
4969 /* add upper_dev to every dev's lower device */
4970 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4971 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4972 i->dev->name, upper_dev->name);
4973 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4975 goto rollback_lower_mesh;
4978 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4981 rollback_lower_mesh:
4983 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4986 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4991 rollback_upper_mesh:
4993 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4996 __netdev_adjacent_dev_unlink(dev, i->dev);
5004 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5005 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5006 if (i == to_i && j == to_j)
5008 __netdev_adjacent_dev_unlink(i->dev, j->dev);
5014 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5020 * netdev_upper_dev_link - Add a link to the upper device
5022 * @upper_dev: new upper device
5024 * Adds a link to device which is upper to this one. The caller must hold
5025 * the RTNL lock. On a failure a negative errno code is returned.
5026 * On success the reference counts are adjusted and the function
5029 int netdev_upper_dev_link(struct net_device *dev,
5030 struct net_device *upper_dev)
5032 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
5034 EXPORT_SYMBOL(netdev_upper_dev_link);
5037 * netdev_master_upper_dev_link - Add a master link to the upper device
5039 * @upper_dev: new upper device
5041 * Adds a link to device which is upper to this one. In this case, only
5042 * one master upper device can be linked, although other non-master devices
5043 * might be linked as well. The caller must hold the RTNL lock.
5044 * On a failure a negative errno code is returned. On success the reference
5045 * counts are adjusted and the function returns zero.
5047 int netdev_master_upper_dev_link(struct net_device *dev,
5048 struct net_device *upper_dev)
5050 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
5052 EXPORT_SYMBOL(netdev_master_upper_dev_link);
5054 int netdev_master_upper_dev_link_private(struct net_device *dev,
5055 struct net_device *upper_dev,
5058 return __netdev_upper_dev_link(dev, upper_dev, true, private);
5060 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
5063 * netdev_upper_dev_unlink - Removes a link to upper device
5065 * @upper_dev: new upper device
5067 * Removes a link to device which is upper to this one. The caller must hold
5070 void netdev_upper_dev_unlink(struct net_device *dev,
5071 struct net_device *upper_dev)
5073 struct netdev_adjacent *i, *j;
5076 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5078 /* Here is the tricky part. We must remove all dev's lower
5079 * devices from all upper_dev's upper devices and vice
5080 * versa, to maintain the graph relationship.
5082 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5083 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5084 __netdev_adjacent_dev_unlink(i->dev, j->dev);
5086 /* remove also the devices itself from lower/upper device
5089 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5090 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
5092 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5093 __netdev_adjacent_dev_unlink(dev, i->dev);
5095 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5097 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5099 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5101 struct netdev_adjacent *iter;
5103 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5104 netdev_adjacent_sysfs_del(iter->dev, oldname,
5105 &iter->dev->adj_list.lower);
5106 netdev_adjacent_sysfs_add(iter->dev, dev,
5107 &iter->dev->adj_list.lower);
5110 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5111 netdev_adjacent_sysfs_del(iter->dev, oldname,
5112 &iter->dev->adj_list.upper);
5113 netdev_adjacent_sysfs_add(iter->dev, dev,
5114 &iter->dev->adj_list.upper);
5118 void *netdev_lower_dev_get_private(struct net_device *dev,
5119 struct net_device *lower_dev)
5121 struct netdev_adjacent *lower;
5125 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
5129 return lower->private;
5131 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5134 int dev_get_nest_level(struct net_device *dev,
5135 bool (*type_check)(struct net_device *dev))
5137 struct net_device *lower = NULL;
5138 struct list_head *iter;
5144 netdev_for_each_lower_dev(dev, lower, iter) {
5145 nest = dev_get_nest_level(lower, type_check);
5146 if (max_nest < nest)
5150 if (type_check(dev))
5155 EXPORT_SYMBOL(dev_get_nest_level);
5157 static void dev_change_rx_flags(struct net_device *dev, int flags)
5159 const struct net_device_ops *ops = dev->netdev_ops;
5161 if (ops->ndo_change_rx_flags)
5162 ops->ndo_change_rx_flags(dev, flags);
5165 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5167 unsigned int old_flags = dev->flags;
5173 dev->flags |= IFF_PROMISC;
5174 dev->promiscuity += inc;
5175 if (dev->promiscuity == 0) {
5178 * If inc causes overflow, untouch promisc and return error.
5181 dev->flags &= ~IFF_PROMISC;
5183 dev->promiscuity -= inc;
5184 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5189 if (dev->flags != old_flags) {
5190 pr_info("device %s %s promiscuous mode\n",
5192 dev->flags & IFF_PROMISC ? "entered" : "left");
5193 if (audit_enabled) {
5194 current_uid_gid(&uid, &gid);
5195 audit_log(current->audit_context, GFP_ATOMIC,
5196 AUDIT_ANOM_PROMISCUOUS,
5197 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5198 dev->name, (dev->flags & IFF_PROMISC),
5199 (old_flags & IFF_PROMISC),
5200 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5201 from_kuid(&init_user_ns, uid),
5202 from_kgid(&init_user_ns, gid),
5203 audit_get_sessionid(current));
5206 dev_change_rx_flags(dev, IFF_PROMISC);
5209 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5214 * dev_set_promiscuity - update promiscuity count on a device
5218 * Add or remove promiscuity from a device. While the count in the device
5219 * remains above zero the interface remains promiscuous. Once it hits zero
5220 * the device reverts back to normal filtering operation. A negative inc
5221 * value is used to drop promiscuity on the device.
5222 * Return 0 if successful or a negative errno code on error.
5224 int dev_set_promiscuity(struct net_device *dev, int inc)
5226 unsigned int old_flags = dev->flags;
5229 err = __dev_set_promiscuity(dev, inc, true);
5232 if (dev->flags != old_flags)
5233 dev_set_rx_mode(dev);
5236 EXPORT_SYMBOL(dev_set_promiscuity);
5238 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5240 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5244 dev->flags |= IFF_ALLMULTI;
5245 dev->allmulti += inc;
5246 if (dev->allmulti == 0) {
5249 * If inc causes overflow, untouch allmulti and return error.
5252 dev->flags &= ~IFF_ALLMULTI;
5254 dev->allmulti -= inc;
5255 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5260 if (dev->flags ^ old_flags) {
5261 dev_change_rx_flags(dev, IFF_ALLMULTI);
5262 dev_set_rx_mode(dev);
5264 __dev_notify_flags(dev, old_flags,
5265 dev->gflags ^ old_gflags);
5271 * dev_set_allmulti - update allmulti count on a device
5275 * Add or remove reception of all multicast frames to a device. While the
5276 * count in the device remains above zero the interface remains listening
5277 * to all interfaces. Once it hits zero the device reverts back to normal
5278 * filtering operation. A negative @inc value is used to drop the counter
5279 * when releasing a resource needing all multicasts.
5280 * Return 0 if successful or a negative errno code on error.
5283 int dev_set_allmulti(struct net_device *dev, int inc)
5285 return __dev_set_allmulti(dev, inc, true);
5287 EXPORT_SYMBOL(dev_set_allmulti);
5290 * Upload unicast and multicast address lists to device and
5291 * configure RX filtering. When the device doesn't support unicast
5292 * filtering it is put in promiscuous mode while unicast addresses
5295 void __dev_set_rx_mode(struct net_device *dev)
5297 const struct net_device_ops *ops = dev->netdev_ops;
5299 /* dev_open will call this function so the list will stay sane. */
5300 if (!(dev->flags&IFF_UP))
5303 if (!netif_device_present(dev))
5306 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5307 /* Unicast addresses changes may only happen under the rtnl,
5308 * therefore calling __dev_set_promiscuity here is safe.
5310 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5311 __dev_set_promiscuity(dev, 1, false);
5312 dev->uc_promisc = true;
5313 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5314 __dev_set_promiscuity(dev, -1, false);
5315 dev->uc_promisc = false;
5319 if (ops->ndo_set_rx_mode)
5320 ops->ndo_set_rx_mode(dev);
5323 void dev_set_rx_mode(struct net_device *dev)
5325 netif_addr_lock_bh(dev);
5326 __dev_set_rx_mode(dev);
5327 netif_addr_unlock_bh(dev);
5331 * dev_get_flags - get flags reported to userspace
5334 * Get the combination of flag bits exported through APIs to userspace.
5336 unsigned int dev_get_flags(const struct net_device *dev)
5340 flags = (dev->flags & ~(IFF_PROMISC |
5345 (dev->gflags & (IFF_PROMISC |
5348 if (netif_running(dev)) {
5349 if (netif_oper_up(dev))
5350 flags |= IFF_RUNNING;
5351 if (netif_carrier_ok(dev))
5352 flags |= IFF_LOWER_UP;
5353 if (netif_dormant(dev))
5354 flags |= IFF_DORMANT;
5359 EXPORT_SYMBOL(dev_get_flags);
5361 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5363 unsigned int old_flags = dev->flags;
5369 * Set the flags on our device.
5372 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5373 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5375 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5379 * Load in the correct multicast list now the flags have changed.
5382 if ((old_flags ^ flags) & IFF_MULTICAST)
5383 dev_change_rx_flags(dev, IFF_MULTICAST);
5385 dev_set_rx_mode(dev);
5388 * Have we downed the interface. We handle IFF_UP ourselves
5389 * according to user attempts to set it, rather than blindly
5394 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5395 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5398 dev_set_rx_mode(dev);
5401 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5402 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5403 unsigned int old_flags = dev->flags;
5405 dev->gflags ^= IFF_PROMISC;
5407 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5408 if (dev->flags != old_flags)
5409 dev_set_rx_mode(dev);
5412 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5413 is important. Some (broken) drivers set IFF_PROMISC, when
5414 IFF_ALLMULTI is requested not asking us and not reporting.
5416 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5417 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5419 dev->gflags ^= IFF_ALLMULTI;
5420 __dev_set_allmulti(dev, inc, false);
5426 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5427 unsigned int gchanges)
5429 unsigned int changes = dev->flags ^ old_flags;
5432 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5434 if (changes & IFF_UP) {
5435 if (dev->flags & IFF_UP)
5436 call_netdevice_notifiers(NETDEV_UP, dev);
5438 call_netdevice_notifiers(NETDEV_DOWN, dev);
5441 if (dev->flags & IFF_UP &&
5442 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5443 struct netdev_notifier_change_info change_info;
5445 change_info.flags_changed = changes;
5446 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5452 * dev_change_flags - change device settings
5454 * @flags: device state flags
5456 * Change settings on device based state flags. The flags are
5457 * in the userspace exported format.
5459 int dev_change_flags(struct net_device *dev, unsigned int flags)
5462 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5464 ret = __dev_change_flags(dev, flags);
5468 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5469 __dev_notify_flags(dev, old_flags, changes);
5472 EXPORT_SYMBOL(dev_change_flags);
5474 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5476 const struct net_device_ops *ops = dev->netdev_ops;
5478 if (ops->ndo_change_mtu)
5479 return ops->ndo_change_mtu(dev, new_mtu);
5486 * dev_set_mtu - Change maximum transfer unit
5488 * @new_mtu: new transfer unit
5490 * Change the maximum transfer size of the network device.
5492 int dev_set_mtu(struct net_device *dev, int new_mtu)
5496 if (new_mtu == dev->mtu)
5499 /* MTU must be positive. */
5503 if (!netif_device_present(dev))
5506 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
5507 err = notifier_to_errno(err);
5511 orig_mtu = dev->mtu;
5512 err = __dev_set_mtu(dev, new_mtu);
5515 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5516 err = notifier_to_errno(err);
5518 /* setting mtu back and notifying everyone again,
5519 * so that they have a chance to revert changes.
5521 __dev_set_mtu(dev, orig_mtu);
5522 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5527 EXPORT_SYMBOL(dev_set_mtu);
5530 * dev_set_group - Change group this device belongs to
5532 * @new_group: group this device should belong to
5534 void dev_set_group(struct net_device *dev, int new_group)
5536 dev->group = new_group;
5538 EXPORT_SYMBOL(dev_set_group);
5541 * dev_set_mac_address - Change Media Access Control Address
5545 * Change the hardware (MAC) address of the device
5547 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5549 const struct net_device_ops *ops = dev->netdev_ops;
5552 if (!ops->ndo_set_mac_address)
5554 if (sa->sa_family != dev->type)
5556 if (!netif_device_present(dev))
5558 err = ops->ndo_set_mac_address(dev, sa);
5561 dev->addr_assign_type = NET_ADDR_SET;
5562 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5563 add_device_randomness(dev->dev_addr, dev->addr_len);
5566 EXPORT_SYMBOL(dev_set_mac_address);
5569 * dev_change_carrier - Change device carrier
5571 * @new_carrier: new value
5573 * Change device carrier
5575 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5577 const struct net_device_ops *ops = dev->netdev_ops;
5579 if (!ops->ndo_change_carrier)
5581 if (!netif_device_present(dev))
5583 return ops->ndo_change_carrier(dev, new_carrier);
5585 EXPORT_SYMBOL(dev_change_carrier);
5588 * dev_get_phys_port_id - Get device physical port ID
5592 * Get device physical port ID
5594 int dev_get_phys_port_id(struct net_device *dev,
5595 struct netdev_phys_port_id *ppid)
5597 const struct net_device_ops *ops = dev->netdev_ops;
5599 if (!ops->ndo_get_phys_port_id)
5601 return ops->ndo_get_phys_port_id(dev, ppid);
5603 EXPORT_SYMBOL(dev_get_phys_port_id);
5606 * dev_new_index - allocate an ifindex
5607 * @net: the applicable net namespace
5609 * Returns a suitable unique value for a new device interface
5610 * number. The caller must hold the rtnl semaphore or the
5611 * dev_base_lock to be sure it remains unique.
5613 static int dev_new_index(struct net *net)
5615 int ifindex = net->ifindex;
5619 if (!__dev_get_by_index(net, ifindex))
5620 return net->ifindex = ifindex;
5624 /* Delayed registration/unregisteration */
5625 static LIST_HEAD(net_todo_list);
5626 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5628 static void net_set_todo(struct net_device *dev)
5630 list_add_tail(&dev->todo_list, &net_todo_list);
5631 dev_net(dev)->dev_unreg_count++;
5634 static void rollback_registered_many(struct list_head *head)
5636 struct net_device *dev, *tmp;
5637 LIST_HEAD(close_head);
5639 BUG_ON(dev_boot_phase);
5642 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5643 /* Some devices call without registering
5644 * for initialization unwind. Remove those
5645 * devices and proceed with the remaining.
5647 if (dev->reg_state == NETREG_UNINITIALIZED) {
5648 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5652 list_del(&dev->unreg_list);
5655 dev->dismantle = true;
5656 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5659 /* If device is running, close it first. */
5660 list_for_each_entry(dev, head, unreg_list)
5661 list_add_tail(&dev->close_list, &close_head);
5662 dev_close_many(&close_head);
5664 list_for_each_entry(dev, head, unreg_list) {
5665 /* And unlink it from device chain. */
5666 unlist_netdevice(dev);
5668 dev->reg_state = NETREG_UNREGISTERING;
5673 list_for_each_entry(dev, head, unreg_list) {
5674 /* Shutdown queueing discipline. */
5678 /* Notify protocols, that we are about to destroy
5679 this device. They should clean all the things.
5681 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5684 * Flush the unicast and multicast chains
5689 if (dev->netdev_ops->ndo_uninit)
5690 dev->netdev_ops->ndo_uninit(dev);
5692 if (!dev->rtnl_link_ops ||
5693 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5694 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5696 /* Notifier chain MUST detach us all upper devices. */
5697 WARN_ON(netdev_has_any_upper_dev(dev));
5699 /* Remove entries from kobject tree */
5700 netdev_unregister_kobject(dev);
5702 /* Remove XPS queueing entries */
5703 netif_reset_xps_queues_gt(dev, 0);
5709 list_for_each_entry(dev, head, unreg_list)
5713 static void rollback_registered(struct net_device *dev)
5717 list_add(&dev->unreg_list, &single);
5718 rollback_registered_many(&single);
5722 static netdev_features_t netdev_fix_features(struct net_device *dev,
5723 netdev_features_t features)
5725 /* Fix illegal checksum combinations */
5726 if ((features & NETIF_F_HW_CSUM) &&
5727 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5728 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5729 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5732 /* TSO requires that SG is present as well. */
5733 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5734 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5735 features &= ~NETIF_F_ALL_TSO;
5738 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5739 !(features & NETIF_F_IP_CSUM)) {
5740 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5741 features &= ~NETIF_F_TSO;
5742 features &= ~NETIF_F_TSO_ECN;
5745 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5746 !(features & NETIF_F_IPV6_CSUM)) {
5747 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5748 features &= ~NETIF_F_TSO6;
5751 /* TSO ECN requires that TSO is present as well. */
5752 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5753 features &= ~NETIF_F_TSO_ECN;
5755 /* Software GSO depends on SG. */
5756 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5757 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5758 features &= ~NETIF_F_GSO;
5761 /* UFO needs SG and checksumming */
5762 if (features & NETIF_F_UFO) {
5763 /* maybe split UFO into V4 and V6? */
5764 if (!((features & NETIF_F_GEN_CSUM) ||
5765 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5766 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5768 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5769 features &= ~NETIF_F_UFO;
5772 if (!(features & NETIF_F_SG)) {
5774 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5775 features &= ~NETIF_F_UFO;
5779 #ifdef CONFIG_NET_RX_BUSY_POLL
5780 if (dev->netdev_ops->ndo_busy_poll)
5781 features |= NETIF_F_BUSY_POLL;
5784 features &= ~NETIF_F_BUSY_POLL;
5789 int __netdev_update_features(struct net_device *dev)
5791 netdev_features_t features;
5796 features = netdev_get_wanted_features(dev);
5798 if (dev->netdev_ops->ndo_fix_features)
5799 features = dev->netdev_ops->ndo_fix_features(dev, features);
5801 /* driver might be less strict about feature dependencies */
5802 features = netdev_fix_features(dev, features);
5804 if (dev->features == features)
5807 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5808 &dev->features, &features);
5810 if (dev->netdev_ops->ndo_set_features)
5811 err = dev->netdev_ops->ndo_set_features(dev, features);
5813 if (unlikely(err < 0)) {
5815 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5816 err, &features, &dev->features);
5821 dev->features = features;
5827 * netdev_update_features - recalculate device features
5828 * @dev: the device to check
5830 * Recalculate dev->features set and send notifications if it
5831 * has changed. Should be called after driver or hardware dependent
5832 * conditions might have changed that influence the features.
5834 void netdev_update_features(struct net_device *dev)
5836 if (__netdev_update_features(dev))
5837 netdev_features_change(dev);
5839 EXPORT_SYMBOL(netdev_update_features);
5842 * netdev_change_features - recalculate device features
5843 * @dev: the device to check
5845 * Recalculate dev->features set and send notifications even
5846 * if they have not changed. Should be called instead of
5847 * netdev_update_features() if also dev->vlan_features might
5848 * have changed to allow the changes to be propagated to stacked
5851 void netdev_change_features(struct net_device *dev)
5853 __netdev_update_features(dev);
5854 netdev_features_change(dev);
5856 EXPORT_SYMBOL(netdev_change_features);
5859 * netif_stacked_transfer_operstate - transfer operstate
5860 * @rootdev: the root or lower level device to transfer state from
5861 * @dev: the device to transfer operstate to
5863 * Transfer operational state from root to device. This is normally
5864 * called when a stacking relationship exists between the root
5865 * device and the device(a leaf device).
5867 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5868 struct net_device *dev)
5870 if (rootdev->operstate == IF_OPER_DORMANT)
5871 netif_dormant_on(dev);
5873 netif_dormant_off(dev);
5875 if (netif_carrier_ok(rootdev)) {
5876 if (!netif_carrier_ok(dev))
5877 netif_carrier_on(dev);
5879 if (netif_carrier_ok(dev))
5880 netif_carrier_off(dev);
5883 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5886 static int netif_alloc_rx_queues(struct net_device *dev)
5888 unsigned int i, count = dev->num_rx_queues;
5889 struct netdev_rx_queue *rx;
5893 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5899 for (i = 0; i < count; i++)
5905 static void netdev_init_one_queue(struct net_device *dev,
5906 struct netdev_queue *queue, void *_unused)
5908 /* Initialize queue lock */
5909 spin_lock_init(&queue->_xmit_lock);
5910 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5911 queue->xmit_lock_owner = -1;
5912 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5915 dql_init(&queue->dql, HZ);
5919 static void netif_free_tx_queues(struct net_device *dev)
5921 if (is_vmalloc_addr(dev->_tx))
5927 static int netif_alloc_netdev_queues(struct net_device *dev)
5929 unsigned int count = dev->num_tx_queues;
5930 struct netdev_queue *tx;
5931 size_t sz = count * sizeof(*tx);
5933 BUG_ON(count < 1 || count > 0xffff);
5935 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5943 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5944 spin_lock_init(&dev->tx_global_lock);
5950 * register_netdevice - register a network device
5951 * @dev: device to register
5953 * Take a completed network device structure and add it to the kernel
5954 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5955 * chain. 0 is returned on success. A negative errno code is returned
5956 * on a failure to set up the device, or if the name is a duplicate.
5958 * Callers must hold the rtnl semaphore. You may want
5959 * register_netdev() instead of this.
5962 * The locking appears insufficient to guarantee two parallel registers
5963 * will not get the same name.
5966 int register_netdevice(struct net_device *dev)
5969 struct net *net = dev_net(dev);
5971 BUG_ON(dev_boot_phase);
5976 /* When net_device's are persistent, this will be fatal. */
5977 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5980 spin_lock_init(&dev->addr_list_lock);
5981 netdev_set_addr_lockdep_class(dev);
5985 ret = dev_get_valid_name(net, dev, dev->name);
5989 /* Init, if this function is available */
5990 if (dev->netdev_ops->ndo_init) {
5991 ret = dev->netdev_ops->ndo_init(dev);
5999 if (((dev->hw_features | dev->features) &
6000 NETIF_F_HW_VLAN_CTAG_FILTER) &&
6001 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
6002 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
6003 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
6010 dev->ifindex = dev_new_index(net);
6011 else if (__dev_get_by_index(net, dev->ifindex))
6014 if (dev->iflink == -1)
6015 dev->iflink = dev->ifindex;
6017 /* Transfer changeable features to wanted_features and enable
6018 * software offloads (GSO and GRO).
6020 dev->hw_features |= NETIF_F_SOFT_FEATURES;
6021 dev->features |= NETIF_F_SOFT_FEATURES;
6022 dev->wanted_features = dev->features & dev->hw_features;
6024 if (!(dev->flags & IFF_LOOPBACK)) {
6025 dev->hw_features |= NETIF_F_NOCACHE_COPY;
6028 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6030 dev->vlan_features |= NETIF_F_HIGHDMA;
6032 /* Make NETIF_F_SG inheritable to tunnel devices.
6034 dev->hw_enc_features |= NETIF_F_SG;
6036 /* Make NETIF_F_SG inheritable to MPLS.
6038 dev->mpls_features |= NETIF_F_SG;
6040 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
6041 ret = notifier_to_errno(ret);
6045 ret = netdev_register_kobject(dev);
6048 dev->reg_state = NETREG_REGISTERED;
6050 __netdev_update_features(dev);
6053 * Default initial state at registry is that the
6054 * device is present.
6057 set_bit(__LINK_STATE_PRESENT, &dev->state);
6059 linkwatch_init_dev(dev);
6061 dev_init_scheduler(dev);
6063 list_netdevice(dev);
6064 add_device_randomness(dev->dev_addr, dev->addr_len);
6066 /* If the device has permanent device address, driver should
6067 * set dev_addr and also addr_assign_type should be set to
6068 * NET_ADDR_PERM (default value).
6070 if (dev->addr_assign_type == NET_ADDR_PERM)
6071 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
6073 /* Notify protocols, that a new device appeared. */
6074 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6075 ret = notifier_to_errno(ret);
6077 rollback_registered(dev);
6078 dev->reg_state = NETREG_UNREGISTERED;
6081 * Prevent userspace races by waiting until the network
6082 * device is fully setup before sending notifications.
6084 if (!dev->rtnl_link_ops ||
6085 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6086 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6092 if (dev->netdev_ops->ndo_uninit)
6093 dev->netdev_ops->ndo_uninit(dev);
6096 EXPORT_SYMBOL(register_netdevice);
6099 * init_dummy_netdev - init a dummy network device for NAPI
6100 * @dev: device to init
6102 * This takes a network device structure and initialize the minimum
6103 * amount of fields so it can be used to schedule NAPI polls without
6104 * registering a full blown interface. This is to be used by drivers
6105 * that need to tie several hardware interfaces to a single NAPI
6106 * poll scheduler due to HW limitations.
6108 int init_dummy_netdev(struct net_device *dev)
6110 /* Clear everything. Note we don't initialize spinlocks
6111 * are they aren't supposed to be taken by any of the
6112 * NAPI code and this dummy netdev is supposed to be
6113 * only ever used for NAPI polls
6115 memset(dev, 0, sizeof(struct net_device));
6117 /* make sure we BUG if trying to hit standard
6118 * register/unregister code path
6120 dev->reg_state = NETREG_DUMMY;
6122 /* NAPI wants this */
6123 INIT_LIST_HEAD(&dev->napi_list);
6125 /* a dummy interface is started by default */
6126 set_bit(__LINK_STATE_PRESENT, &dev->state);
6127 set_bit(__LINK_STATE_START, &dev->state);
6129 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6130 * because users of this 'device' dont need to change
6136 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6140 * register_netdev - register a network device
6141 * @dev: device to register
6143 * Take a completed network device structure and add it to the kernel
6144 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6145 * chain. 0 is returned on success. A negative errno code is returned
6146 * on a failure to set up the device, or if the name is a duplicate.
6148 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6149 * and expands the device name if you passed a format string to
6152 int register_netdev(struct net_device *dev)
6157 err = register_netdevice(dev);
6161 EXPORT_SYMBOL(register_netdev);
6163 int netdev_refcnt_read(const struct net_device *dev)
6167 for_each_possible_cpu(i)
6168 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6171 EXPORT_SYMBOL(netdev_refcnt_read);
6174 * netdev_wait_allrefs - wait until all references are gone.
6175 * @dev: target net_device
6177 * This is called when unregistering network devices.
6179 * Any protocol or device that holds a reference should register
6180 * for netdevice notification, and cleanup and put back the
6181 * reference if they receive an UNREGISTER event.
6182 * We can get stuck here if buggy protocols don't correctly
6185 static void netdev_wait_allrefs(struct net_device *dev)
6187 unsigned long rebroadcast_time, warning_time;
6190 linkwatch_forget_dev(dev);
6192 rebroadcast_time = warning_time = jiffies;
6193 refcnt = netdev_refcnt_read(dev);
6195 while (refcnt != 0) {
6196 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6199 /* Rebroadcast unregister notification */
6200 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6206 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6207 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6209 /* We must not have linkwatch events
6210 * pending on unregister. If this
6211 * happens, we simply run the queue
6212 * unscheduled, resulting in a noop
6215 linkwatch_run_queue();
6220 rebroadcast_time = jiffies;
6225 refcnt = netdev_refcnt_read(dev);
6227 if (time_after(jiffies, warning_time + 10 * HZ)) {
6228 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6230 warning_time = jiffies;
6239 * register_netdevice(x1);
6240 * register_netdevice(x2);
6242 * unregister_netdevice(y1);
6243 * unregister_netdevice(y2);
6249 * We are invoked by rtnl_unlock().
6250 * This allows us to deal with problems:
6251 * 1) We can delete sysfs objects which invoke hotplug
6252 * without deadlocking with linkwatch via keventd.
6253 * 2) Since we run with the RTNL semaphore not held, we can sleep
6254 * safely in order to wait for the netdev refcnt to drop to zero.
6256 * We must not return until all unregister events added during
6257 * the interval the lock was held have been completed.
6259 void netdev_run_todo(void)
6261 struct list_head list;
6263 /* Snapshot list, allow later requests */
6264 list_replace_init(&net_todo_list, &list);
6269 /* Wait for rcu callbacks to finish before next phase */
6270 if (!list_empty(&list))
6273 while (!list_empty(&list)) {
6274 struct net_device *dev
6275 = list_first_entry(&list, struct net_device, todo_list);
6276 list_del(&dev->todo_list);
6279 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6282 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6283 pr_err("network todo '%s' but state %d\n",
6284 dev->name, dev->reg_state);
6289 dev->reg_state = NETREG_UNREGISTERED;
6291 on_each_cpu(flush_backlog, dev, 1);
6293 netdev_wait_allrefs(dev);
6296 BUG_ON(netdev_refcnt_read(dev));
6297 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6298 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6299 WARN_ON(dev->dn_ptr);
6301 if (dev->destructor)
6302 dev->destructor(dev);
6304 /* Report a network device has been unregistered */
6306 dev_net(dev)->dev_unreg_count--;
6308 wake_up(&netdev_unregistering_wq);
6310 /* Free network device */
6311 kobject_put(&dev->dev.kobj);
6315 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6316 * fields in the same order, with only the type differing.
6318 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6319 const struct net_device_stats *netdev_stats)
6321 #if BITS_PER_LONG == 64
6322 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6323 memcpy(stats64, netdev_stats, sizeof(*stats64));
6325 size_t i, n = sizeof(*stats64) / sizeof(u64);
6326 const unsigned long *src = (const unsigned long *)netdev_stats;
6327 u64 *dst = (u64 *)stats64;
6329 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6330 sizeof(*stats64) / sizeof(u64));
6331 for (i = 0; i < n; i++)
6335 EXPORT_SYMBOL(netdev_stats_to_stats64);
6338 * dev_get_stats - get network device statistics
6339 * @dev: device to get statistics from
6340 * @storage: place to store stats
6342 * Get network statistics from device. Return @storage.
6343 * The device driver may provide its own method by setting
6344 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6345 * otherwise the internal statistics structure is used.
6347 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6348 struct rtnl_link_stats64 *storage)
6350 const struct net_device_ops *ops = dev->netdev_ops;
6352 if (ops->ndo_get_stats64) {
6353 memset(storage, 0, sizeof(*storage));
6354 ops->ndo_get_stats64(dev, storage);
6355 } else if (ops->ndo_get_stats) {
6356 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6358 netdev_stats_to_stats64(storage, &dev->stats);
6360 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6361 storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6364 EXPORT_SYMBOL(dev_get_stats);
6366 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6368 struct netdev_queue *queue = dev_ingress_queue(dev);
6370 #ifdef CONFIG_NET_CLS_ACT
6373 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6376 netdev_init_one_queue(dev, queue, NULL);
6377 queue->qdisc = &noop_qdisc;
6378 queue->qdisc_sleeping = &noop_qdisc;
6379 rcu_assign_pointer(dev->ingress_queue, queue);
6384 static const struct ethtool_ops default_ethtool_ops;
6386 void netdev_set_default_ethtool_ops(struct net_device *dev,
6387 const struct ethtool_ops *ops)
6389 if (dev->ethtool_ops == &default_ethtool_ops)
6390 dev->ethtool_ops = ops;
6392 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6394 void netdev_freemem(struct net_device *dev)
6396 char *addr = (char *)dev - dev->padded;
6398 if (is_vmalloc_addr(addr))
6405 * alloc_netdev_mqs - allocate network device
6406 * @sizeof_priv: size of private data to allocate space for
6407 * @name: device name format string
6408 * @setup: callback to initialize device
6409 * @txqs: the number of TX subqueues to allocate
6410 * @rxqs: the number of RX subqueues to allocate
6412 * Allocates a struct net_device with private data area for driver use
6413 * and performs basic initialization. Also allocates subqueue structs
6414 * for each queue on the device.
6416 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6417 void (*setup)(struct net_device *),
6418 unsigned int txqs, unsigned int rxqs)
6420 struct net_device *dev;
6422 struct net_device *p;
6424 BUG_ON(strlen(name) >= sizeof(dev->name));
6427 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6433 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6438 alloc_size = sizeof(struct net_device);
6440 /* ensure 32-byte alignment of private area */
6441 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6442 alloc_size += sizeof_priv;
6444 /* ensure 32-byte alignment of whole construct */
6445 alloc_size += NETDEV_ALIGN - 1;
6447 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6449 p = vzalloc(alloc_size);
6453 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6454 dev->padded = (char *)dev - (char *)p;
6456 dev->pcpu_refcnt = alloc_percpu(int);
6457 if (!dev->pcpu_refcnt)
6460 if (dev_addr_init(dev))
6466 dev_net_set(dev, &init_net);
6468 dev->gso_max_size = GSO_MAX_SIZE;
6469 dev->gso_max_segs = GSO_MAX_SEGS;
6471 INIT_LIST_HEAD(&dev->napi_list);
6472 INIT_LIST_HEAD(&dev->unreg_list);
6473 INIT_LIST_HEAD(&dev->close_list);
6474 INIT_LIST_HEAD(&dev->link_watch_list);
6475 INIT_LIST_HEAD(&dev->adj_list.upper);
6476 INIT_LIST_HEAD(&dev->adj_list.lower);
6477 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6478 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6479 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6482 dev->num_tx_queues = txqs;
6483 dev->real_num_tx_queues = txqs;
6484 if (netif_alloc_netdev_queues(dev))
6488 dev->num_rx_queues = rxqs;
6489 dev->real_num_rx_queues = rxqs;
6490 if (netif_alloc_rx_queues(dev))
6494 strcpy(dev->name, name);
6495 dev->group = INIT_NETDEV_GROUP;
6496 if (!dev->ethtool_ops)
6497 dev->ethtool_ops = &default_ethtool_ops;
6505 free_percpu(dev->pcpu_refcnt);
6507 netdev_freemem(dev);
6510 EXPORT_SYMBOL(alloc_netdev_mqs);
6513 * free_netdev - free network device
6516 * This function does the last stage of destroying an allocated device
6517 * interface. The reference to the device object is released.
6518 * If this is the last reference then it will be freed.
6520 void free_netdev(struct net_device *dev)
6522 struct napi_struct *p, *n;
6524 release_net(dev_net(dev));
6526 netif_free_tx_queues(dev);
6531 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6533 /* Flush device addresses */
6534 dev_addr_flush(dev);
6536 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6539 free_percpu(dev->pcpu_refcnt);
6540 dev->pcpu_refcnt = NULL;
6542 /* Compatibility with error handling in drivers */
6543 if (dev->reg_state == NETREG_UNINITIALIZED) {
6544 netdev_freemem(dev);
6548 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6549 dev->reg_state = NETREG_RELEASED;
6551 /* will free via device release */
6552 put_device(&dev->dev);
6554 EXPORT_SYMBOL(free_netdev);
6557 * synchronize_net - Synchronize with packet receive processing
6559 * Wait for packets currently being received to be done.
6560 * Does not block later packets from starting.
6562 void synchronize_net(void)
6565 if (rtnl_is_locked())
6566 synchronize_rcu_expedited();
6570 EXPORT_SYMBOL(synchronize_net);
6573 * unregister_netdevice_queue - remove device from the kernel
6577 * This function shuts down a device interface and removes it
6578 * from the kernel tables.
6579 * If head not NULL, device is queued to be unregistered later.
6581 * Callers must hold the rtnl semaphore. You may want
6582 * unregister_netdev() instead of this.
6585 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6590 list_move_tail(&dev->unreg_list, head);
6592 rollback_registered(dev);
6593 /* Finish processing unregister after unlock */
6597 EXPORT_SYMBOL(unregister_netdevice_queue);
6600 * unregister_netdevice_many - unregister many devices
6601 * @head: list of devices
6603 void unregister_netdevice_many(struct list_head *head)
6605 struct net_device *dev;
6607 if (!list_empty(head)) {
6608 rollback_registered_many(head);
6609 list_for_each_entry(dev, head, unreg_list)
6613 EXPORT_SYMBOL(unregister_netdevice_many);
6616 * unregister_netdev - remove device from the kernel
6619 * This function shuts down a device interface and removes it
6620 * from the kernel tables.
6622 * This is just a wrapper for unregister_netdevice that takes
6623 * the rtnl semaphore. In general you want to use this and not
6624 * unregister_netdevice.
6626 void unregister_netdev(struct net_device *dev)
6629 unregister_netdevice(dev);
6632 EXPORT_SYMBOL(unregister_netdev);
6635 * dev_change_net_namespace - move device to different nethost namespace
6637 * @net: network namespace
6638 * @pat: If not NULL name pattern to try if the current device name
6639 * is already taken in the destination network namespace.
6641 * This function shuts down a device interface and moves it
6642 * to a new network namespace. On success 0 is returned, on
6643 * a failure a netagive errno code is returned.
6645 * Callers must hold the rtnl semaphore.
6648 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6654 /* Don't allow namespace local devices to be moved. */
6656 if (dev->features & NETIF_F_NETNS_LOCAL)
6659 /* Ensure the device has been registrered */
6660 if (dev->reg_state != NETREG_REGISTERED)
6663 /* Get out if there is nothing todo */
6665 if (net_eq(dev_net(dev), net))
6668 /* Pick the destination device name, and ensure
6669 * we can use it in the destination network namespace.
6672 if (__dev_get_by_name(net, dev->name)) {
6673 /* We get here if we can't use the current device name */
6676 if (dev_get_valid_name(net, dev, pat) < 0)
6681 * And now a mini version of register_netdevice unregister_netdevice.
6684 /* If device is running close it first. */
6687 /* And unlink it from device chain */
6689 unlist_netdevice(dev);
6693 /* Shutdown queueing discipline. */
6696 /* Notify protocols, that we are about to destroy
6697 this device. They should clean all the things.
6699 Note that dev->reg_state stays at NETREG_REGISTERED.
6700 This is wanted because this way 8021q and macvlan know
6701 the device is just moving and can keep their slaves up.
6703 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6705 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6706 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6709 * Flush the unicast and multicast chains
6714 /* Send a netdev-removed uevent to the old namespace */
6715 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6717 /* Actually switch the network namespace */
6718 dev_net_set(dev, net);
6720 /* If there is an ifindex conflict assign a new one */
6721 if (__dev_get_by_index(net, dev->ifindex)) {
6722 int iflink = (dev->iflink == dev->ifindex);
6723 dev->ifindex = dev_new_index(net);
6725 dev->iflink = dev->ifindex;
6728 /* Send a netdev-add uevent to the new namespace */
6729 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6731 /* Fixup kobjects */
6732 err = device_rename(&dev->dev, dev->name);
6735 /* Add the device back in the hashes */
6736 list_netdevice(dev);
6738 /* Notify protocols, that a new device appeared. */
6739 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6742 * Prevent userspace races by waiting until the network
6743 * device is fully setup before sending notifications.
6745 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6752 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6754 static int dev_cpu_callback(struct notifier_block *nfb,
6755 unsigned long action,
6758 struct sk_buff **list_skb;
6759 struct sk_buff *skb;
6760 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6761 struct softnet_data *sd, *oldsd;
6763 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6766 local_irq_disable();
6767 cpu = smp_processor_id();
6768 sd = &per_cpu(softnet_data, cpu);
6769 oldsd = &per_cpu(softnet_data, oldcpu);
6771 /* Find end of our completion_queue. */
6772 list_skb = &sd->completion_queue;
6774 list_skb = &(*list_skb)->next;
6775 /* Append completion queue from offline CPU. */
6776 *list_skb = oldsd->completion_queue;
6777 oldsd->completion_queue = NULL;
6779 /* Append output queue from offline CPU. */
6780 if (oldsd->output_queue) {
6781 *sd->output_queue_tailp = oldsd->output_queue;
6782 sd->output_queue_tailp = oldsd->output_queue_tailp;
6783 oldsd->output_queue = NULL;
6784 oldsd->output_queue_tailp = &oldsd->output_queue;
6786 /* Append NAPI poll list from offline CPU. */
6787 if (!list_empty(&oldsd->poll_list)) {
6788 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6789 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6792 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6795 /* Process offline CPU's input_pkt_queue */
6796 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6797 netif_rx_internal(skb);
6798 input_queue_head_incr(oldsd);
6800 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6801 netif_rx_internal(skb);
6802 input_queue_head_incr(oldsd);
6810 * netdev_increment_features - increment feature set by one
6811 * @all: current feature set
6812 * @one: new feature set
6813 * @mask: mask feature set
6815 * Computes a new feature set after adding a device with feature set
6816 * @one to the master device with current feature set @all. Will not
6817 * enable anything that is off in @mask. Returns the new feature set.
6819 netdev_features_t netdev_increment_features(netdev_features_t all,
6820 netdev_features_t one, netdev_features_t mask)
6822 if (mask & NETIF_F_GEN_CSUM)
6823 mask |= NETIF_F_ALL_CSUM;
6824 mask |= NETIF_F_VLAN_CHALLENGED;
6826 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6827 all &= one | ~NETIF_F_ALL_FOR_ALL;
6829 /* If one device supports hw checksumming, set for all. */
6830 if (all & NETIF_F_GEN_CSUM)
6831 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6835 EXPORT_SYMBOL(netdev_increment_features);
6837 static struct hlist_head * __net_init netdev_create_hash(void)
6840 struct hlist_head *hash;
6842 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6844 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6845 INIT_HLIST_HEAD(&hash[i]);
6850 /* Initialize per network namespace state */
6851 static int __net_init netdev_init(struct net *net)
6853 if (net != &init_net)
6854 INIT_LIST_HEAD(&net->dev_base_head);
6856 net->dev_name_head = netdev_create_hash();
6857 if (net->dev_name_head == NULL)
6860 net->dev_index_head = netdev_create_hash();
6861 if (net->dev_index_head == NULL)
6867 kfree(net->dev_name_head);
6873 * netdev_drivername - network driver for the device
6874 * @dev: network device
6876 * Determine network driver for device.
6878 const char *netdev_drivername(const struct net_device *dev)
6880 const struct device_driver *driver;
6881 const struct device *parent;
6882 const char *empty = "";
6884 parent = dev->dev.parent;
6888 driver = parent->driver;
6889 if (driver && driver->name)
6890 return driver->name;
6894 static int __netdev_printk(const char *level, const struct net_device *dev,
6895 struct va_format *vaf)
6899 if (dev && dev->dev.parent) {
6900 r = dev_printk_emit(level[1] - '0',
6903 dev_driver_string(dev->dev.parent),
6904 dev_name(dev->dev.parent),
6905 netdev_name(dev), vaf);
6907 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6909 r = printk("%s(NULL net_device): %pV", level, vaf);
6915 int netdev_printk(const char *level, const struct net_device *dev,
6916 const char *format, ...)
6918 struct va_format vaf;
6922 va_start(args, format);
6927 r = __netdev_printk(level, dev, &vaf);
6933 EXPORT_SYMBOL(netdev_printk);
6935 #define define_netdev_printk_level(func, level) \
6936 int func(const struct net_device *dev, const char *fmt, ...) \
6939 struct va_format vaf; \
6942 va_start(args, fmt); \
6947 r = __netdev_printk(level, dev, &vaf); \
6953 EXPORT_SYMBOL(func);
6955 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6956 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6957 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6958 define_netdev_printk_level(netdev_err, KERN_ERR);
6959 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6960 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6961 define_netdev_printk_level(netdev_info, KERN_INFO);
6963 static void __net_exit netdev_exit(struct net *net)
6965 kfree(net->dev_name_head);
6966 kfree(net->dev_index_head);
6969 static struct pernet_operations __net_initdata netdev_net_ops = {
6970 .init = netdev_init,
6971 .exit = netdev_exit,
6974 static void __net_exit default_device_exit(struct net *net)
6976 struct net_device *dev, *aux;
6978 * Push all migratable network devices back to the
6979 * initial network namespace
6982 for_each_netdev_safe(net, dev, aux) {
6984 char fb_name[IFNAMSIZ];
6986 /* Ignore unmoveable devices (i.e. loopback) */
6987 if (dev->features & NETIF_F_NETNS_LOCAL)
6990 /* Leave virtual devices for the generic cleanup */
6991 if (dev->rtnl_link_ops)
6994 /* Push remaining network devices to init_net */
6995 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6996 err = dev_change_net_namespace(dev, &init_net, fb_name);
6998 pr_emerg("%s: failed to move %s to init_net: %d\n",
6999 __func__, dev->name, err);
7006 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
7008 /* Return with the rtnl_lock held when there are no network
7009 * devices unregistering in any network namespace in net_list.
7016 prepare_to_wait(&netdev_unregistering_wq, &wait,
7017 TASK_UNINTERRUPTIBLE);
7018 unregistering = false;
7020 list_for_each_entry(net, net_list, exit_list) {
7021 if (net->dev_unreg_count > 0) {
7022 unregistering = true;
7031 finish_wait(&netdev_unregistering_wq, &wait);
7034 static void __net_exit default_device_exit_batch(struct list_head *net_list)
7036 /* At exit all network devices most be removed from a network
7037 * namespace. Do this in the reverse order of registration.
7038 * Do this across as many network namespaces as possible to
7039 * improve batching efficiency.
7041 struct net_device *dev;
7043 LIST_HEAD(dev_kill_list);
7045 /* To prevent network device cleanup code from dereferencing
7046 * loopback devices or network devices that have been freed
7047 * wait here for all pending unregistrations to complete,
7048 * before unregistring the loopback device and allowing the
7049 * network namespace be freed.
7051 * The netdev todo list containing all network devices
7052 * unregistrations that happen in default_device_exit_batch
7053 * will run in the rtnl_unlock() at the end of
7054 * default_device_exit_batch.
7056 rtnl_lock_unregistering(net_list);
7057 list_for_each_entry(net, net_list, exit_list) {
7058 for_each_netdev_reverse(net, dev) {
7059 if (dev->rtnl_link_ops)
7060 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
7062 unregister_netdevice_queue(dev, &dev_kill_list);
7065 unregister_netdevice_many(&dev_kill_list);
7066 list_del(&dev_kill_list);
7070 static struct pernet_operations __net_initdata default_device_ops = {
7071 .exit = default_device_exit,
7072 .exit_batch = default_device_exit_batch,
7076 * Initialize the DEV module. At boot time this walks the device list and
7077 * unhooks any devices that fail to initialise (normally hardware not
7078 * present) and leaves us with a valid list of present and active devices.
7083 * This is called single threaded during boot, so no need
7084 * to take the rtnl semaphore.
7086 static int __init net_dev_init(void)
7088 int i, rc = -ENOMEM;
7090 BUG_ON(!dev_boot_phase);
7092 if (dev_proc_init())
7095 if (netdev_kobject_init())
7098 INIT_LIST_HEAD(&ptype_all);
7099 for (i = 0; i < PTYPE_HASH_SIZE; i++)
7100 INIT_LIST_HEAD(&ptype_base[i]);
7102 INIT_LIST_HEAD(&offload_base);
7104 if (register_pernet_subsys(&netdev_net_ops))
7108 * Initialise the packet receive queues.
7111 for_each_possible_cpu(i) {
7112 struct softnet_data *sd = &per_cpu(softnet_data, i);
7114 skb_queue_head_init(&sd->input_pkt_queue);
7115 skb_queue_head_init(&sd->process_queue);
7116 INIT_LIST_HEAD(&sd->poll_list);
7117 sd->output_queue_tailp = &sd->output_queue;
7119 sd->csd.func = rps_trigger_softirq;
7124 sd->backlog.poll = process_backlog;
7125 sd->backlog.weight = weight_p;
7130 /* The loopback device is special if any other network devices
7131 * is present in a network namespace the loopback device must
7132 * be present. Since we now dynamically allocate and free the
7133 * loopback device ensure this invariant is maintained by
7134 * keeping the loopback device as the first device on the
7135 * list of network devices. Ensuring the loopback devices
7136 * is the first device that appears and the last network device
7139 if (register_pernet_device(&loopback_net_ops))
7142 if (register_pernet_device(&default_device_ops))
7145 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7146 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7148 hotcpu_notifier(dev_cpu_callback, 0);
7155 subsys_initcall(net_dev_init);