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_rx_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_rx_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 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1318 clear_bit(__LINK_STATE_START, &dev->state);
1320 /* Synchronize to scheduled poll. We cannot touch poll list, it
1321 * can be even on different cpu. So just clear netif_running().
1323 * dev->stop() will invoke napi_disable() on all of it's
1324 * napi_struct instances on this device.
1326 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1329 dev_deactivate_many(head);
1331 list_for_each_entry(dev, head, close_list) {
1332 const struct net_device_ops *ops = dev->netdev_ops;
1335 * Call the device specific close. This cannot fail.
1336 * Only if device is UP
1338 * We allow it to be called even after a DETACH hot-plug
1344 dev->flags &= ~IFF_UP;
1345 net_dmaengine_put();
1351 static int __dev_close(struct net_device *dev)
1356 /* Temporarily disable netpoll until the interface is down */
1357 netpoll_rx_disable(dev);
1359 list_add(&dev->close_list, &single);
1360 retval = __dev_close_many(&single);
1363 netpoll_rx_enable(dev);
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 /* Block netpoll rx while the interface is going down */
1402 netpoll_rx_disable(dev);
1404 list_add(&dev->close_list, &single);
1405 dev_close_many(&single);
1408 netpoll_rx_enable(dev);
1412 EXPORT_SYMBOL(dev_close);
1416 * dev_disable_lro - disable Large Receive Offload on a device
1419 * Disable Large Receive Offload (LRO) on a net device. Must be
1420 * called under RTNL. This is needed if received packets may be
1421 * forwarded to another interface.
1423 void dev_disable_lro(struct net_device *dev)
1426 * If we're trying to disable lro on a vlan device
1427 * use the underlying physical device instead
1429 if (is_vlan_dev(dev))
1430 dev = vlan_dev_real_dev(dev);
1432 /* the same for macvlan devices */
1433 if (netif_is_macvlan(dev))
1434 dev = macvlan_dev_real_dev(dev);
1436 dev->wanted_features &= ~NETIF_F_LRO;
1437 netdev_update_features(dev);
1439 if (unlikely(dev->features & NETIF_F_LRO))
1440 netdev_WARN(dev, "failed to disable LRO!\n");
1442 EXPORT_SYMBOL(dev_disable_lro);
1444 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1445 struct net_device *dev)
1447 struct netdev_notifier_info info;
1449 netdev_notifier_info_init(&info, dev);
1450 return nb->notifier_call(nb, val, &info);
1453 static int dev_boot_phase = 1;
1456 * register_netdevice_notifier - register a network notifier block
1459 * Register a notifier to be called when network device events occur.
1460 * The notifier passed is linked into the kernel structures and must
1461 * not be reused until it has been unregistered. A negative errno code
1462 * is returned on a failure.
1464 * When registered all registration and up events are replayed
1465 * to the new notifier to allow device to have a race free
1466 * view of the network device list.
1469 int register_netdevice_notifier(struct notifier_block *nb)
1471 struct net_device *dev;
1472 struct net_device *last;
1477 err = raw_notifier_chain_register(&netdev_chain, nb);
1483 for_each_netdev(net, dev) {
1484 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1485 err = notifier_to_errno(err);
1489 if (!(dev->flags & IFF_UP))
1492 call_netdevice_notifier(nb, NETDEV_UP, dev);
1503 for_each_netdev(net, dev) {
1507 if (dev->flags & IFF_UP) {
1508 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1510 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1512 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1517 raw_notifier_chain_unregister(&netdev_chain, nb);
1520 EXPORT_SYMBOL(register_netdevice_notifier);
1523 * unregister_netdevice_notifier - unregister a network notifier block
1526 * Unregister a notifier previously registered by
1527 * register_netdevice_notifier(). The notifier is unlinked into the
1528 * kernel structures and may then be reused. A negative errno code
1529 * is returned on a failure.
1531 * After unregistering unregister and down device events are synthesized
1532 * for all devices on the device list to the removed notifier to remove
1533 * the need for special case cleanup code.
1536 int unregister_netdevice_notifier(struct notifier_block *nb)
1538 struct net_device *dev;
1543 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1548 for_each_netdev(net, dev) {
1549 if (dev->flags & IFF_UP) {
1550 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1552 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1554 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1561 EXPORT_SYMBOL(unregister_netdevice_notifier);
1564 * call_netdevice_notifiers_info - call all network notifier blocks
1565 * @val: value passed unmodified to notifier function
1566 * @dev: net_device pointer passed unmodified to notifier function
1567 * @info: notifier information data
1569 * Call all network notifier blocks. Parameters and return value
1570 * are as for raw_notifier_call_chain().
1573 static int call_netdevice_notifiers_info(unsigned long val,
1574 struct net_device *dev,
1575 struct netdev_notifier_info *info)
1578 netdev_notifier_info_init(info, dev);
1579 return raw_notifier_call_chain(&netdev_chain, val, info);
1583 * call_netdevice_notifiers - call all network notifier blocks
1584 * @val: value passed unmodified to notifier function
1585 * @dev: net_device pointer passed unmodified to notifier function
1587 * Call all network notifier blocks. Parameters and return value
1588 * are as for raw_notifier_call_chain().
1591 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1593 struct netdev_notifier_info info;
1595 return call_netdevice_notifiers_info(val, dev, &info);
1597 EXPORT_SYMBOL(call_netdevice_notifiers);
1599 static struct static_key netstamp_needed __read_mostly;
1600 #ifdef HAVE_JUMP_LABEL
1601 /* We are not allowed to call static_key_slow_dec() from irq context
1602 * If net_disable_timestamp() is called from irq context, defer the
1603 * static_key_slow_dec() calls.
1605 static atomic_t netstamp_needed_deferred;
1608 void net_enable_timestamp(void)
1610 #ifdef HAVE_JUMP_LABEL
1611 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1615 static_key_slow_dec(&netstamp_needed);
1619 static_key_slow_inc(&netstamp_needed);
1621 EXPORT_SYMBOL(net_enable_timestamp);
1623 void net_disable_timestamp(void)
1625 #ifdef HAVE_JUMP_LABEL
1626 if (in_interrupt()) {
1627 atomic_inc(&netstamp_needed_deferred);
1631 static_key_slow_dec(&netstamp_needed);
1633 EXPORT_SYMBOL(net_disable_timestamp);
1635 static inline void net_timestamp_set(struct sk_buff *skb)
1637 skb->tstamp.tv64 = 0;
1638 if (static_key_false(&netstamp_needed))
1639 __net_timestamp(skb);
1642 #define net_timestamp_check(COND, SKB) \
1643 if (static_key_false(&netstamp_needed)) { \
1644 if ((COND) && !(SKB)->tstamp.tv64) \
1645 __net_timestamp(SKB); \
1648 static inline bool is_skb_forwardable(struct net_device *dev,
1649 struct sk_buff *skb)
1653 if (!(dev->flags & IFF_UP))
1656 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1657 if (skb->len <= len)
1660 /* if TSO is enabled, we don't care about the length as the packet
1661 * could be forwarded without being segmented before
1663 if (skb_is_gso(skb))
1670 * dev_forward_skb - loopback an skb to another netif
1672 * @dev: destination network device
1673 * @skb: buffer to forward
1676 * NET_RX_SUCCESS (no congestion)
1677 * NET_RX_DROP (packet was dropped, but freed)
1679 * dev_forward_skb can be used for injecting an skb from the
1680 * start_xmit function of one device into the receive queue
1681 * of another device.
1683 * The receiving device may be in another namespace, so
1684 * we have to clear all information in the skb that could
1685 * impact namespace isolation.
1687 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1689 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1690 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1691 atomic_long_inc(&dev->rx_dropped);
1697 if (unlikely(!is_skb_forwardable(dev, skb))) {
1698 atomic_long_inc(&dev->rx_dropped);
1703 skb_scrub_packet(skb, true);
1704 skb->protocol = eth_type_trans(skb, dev);
1706 return netif_rx_internal(skb);
1708 EXPORT_SYMBOL_GPL(dev_forward_skb);
1710 static inline int deliver_skb(struct sk_buff *skb,
1711 struct packet_type *pt_prev,
1712 struct net_device *orig_dev)
1714 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1716 atomic_inc(&skb->users);
1717 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1720 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1722 if (!ptype->af_packet_priv || !skb->sk)
1725 if (ptype->id_match)
1726 return ptype->id_match(ptype, skb->sk);
1727 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1734 * Support routine. Sends outgoing frames to any network
1735 * taps currently in use.
1738 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1740 struct packet_type *ptype;
1741 struct sk_buff *skb2 = NULL;
1742 struct packet_type *pt_prev = NULL;
1745 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1746 /* Never send packets back to the socket
1747 * they originated from - MvS (miquels@drinkel.ow.org)
1749 if ((ptype->dev == dev || !ptype->dev) &&
1750 (!skb_loop_sk(ptype, skb))) {
1752 deliver_skb(skb2, pt_prev, skb->dev);
1757 skb2 = skb_clone(skb, GFP_ATOMIC);
1761 net_timestamp_set(skb2);
1763 /* skb->nh should be correctly
1764 set by sender, so that the second statement is
1765 just protection against buggy protocols.
1767 skb_reset_mac_header(skb2);
1769 if (skb_network_header(skb2) < skb2->data ||
1770 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1771 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1772 ntohs(skb2->protocol),
1774 skb_reset_network_header(skb2);
1777 skb2->transport_header = skb2->network_header;
1778 skb2->pkt_type = PACKET_OUTGOING;
1783 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1788 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1789 * @dev: Network device
1790 * @txq: number of queues available
1792 * If real_num_tx_queues is changed the tc mappings may no longer be
1793 * valid. To resolve this verify the tc mapping remains valid and if
1794 * not NULL the mapping. With no priorities mapping to this
1795 * offset/count pair it will no longer be used. In the worst case TC0
1796 * is invalid nothing can be done so disable priority mappings. If is
1797 * expected that drivers will fix this mapping if they can before
1798 * calling netif_set_real_num_tx_queues.
1800 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1803 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1805 /* If TC0 is invalidated disable TC mapping */
1806 if (tc->offset + tc->count > txq) {
1807 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1812 /* Invalidated prio to tc mappings set to TC0 */
1813 for (i = 1; i < TC_BITMASK + 1; i++) {
1814 int q = netdev_get_prio_tc_map(dev, i);
1816 tc = &dev->tc_to_txq[q];
1817 if (tc->offset + tc->count > txq) {
1818 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1820 netdev_set_prio_tc_map(dev, i, 0);
1826 static DEFINE_MUTEX(xps_map_mutex);
1827 #define xmap_dereference(P) \
1828 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1830 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1833 struct xps_map *map = NULL;
1837 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1839 for (pos = 0; map && pos < map->len; pos++) {
1840 if (map->queues[pos] == index) {
1842 map->queues[pos] = map->queues[--map->len];
1844 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1845 kfree_rcu(map, rcu);
1855 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1857 struct xps_dev_maps *dev_maps;
1859 bool active = false;
1861 mutex_lock(&xps_map_mutex);
1862 dev_maps = xmap_dereference(dev->xps_maps);
1867 for_each_possible_cpu(cpu) {
1868 for (i = index; i < dev->num_tx_queues; i++) {
1869 if (!remove_xps_queue(dev_maps, cpu, i))
1872 if (i == dev->num_tx_queues)
1877 RCU_INIT_POINTER(dev->xps_maps, NULL);
1878 kfree_rcu(dev_maps, rcu);
1881 for (i = index; i < dev->num_tx_queues; i++)
1882 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1886 mutex_unlock(&xps_map_mutex);
1889 static struct xps_map *expand_xps_map(struct xps_map *map,
1892 struct xps_map *new_map;
1893 int alloc_len = XPS_MIN_MAP_ALLOC;
1896 for (pos = 0; map && pos < map->len; pos++) {
1897 if (map->queues[pos] != index)
1902 /* Need to add queue to this CPU's existing map */
1904 if (pos < map->alloc_len)
1907 alloc_len = map->alloc_len * 2;
1910 /* Need to allocate new map to store queue on this CPU's map */
1911 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1916 for (i = 0; i < pos; i++)
1917 new_map->queues[i] = map->queues[i];
1918 new_map->alloc_len = alloc_len;
1924 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1927 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1928 struct xps_map *map, *new_map;
1929 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1930 int cpu, numa_node_id = -2;
1931 bool active = false;
1933 mutex_lock(&xps_map_mutex);
1935 dev_maps = xmap_dereference(dev->xps_maps);
1937 /* allocate memory for queue storage */
1938 for_each_online_cpu(cpu) {
1939 if (!cpumask_test_cpu(cpu, mask))
1943 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1944 if (!new_dev_maps) {
1945 mutex_unlock(&xps_map_mutex);
1949 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1952 map = expand_xps_map(map, cpu, index);
1956 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1960 goto out_no_new_maps;
1962 for_each_possible_cpu(cpu) {
1963 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1964 /* add queue to CPU maps */
1967 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1968 while ((pos < map->len) && (map->queues[pos] != index))
1971 if (pos == map->len)
1972 map->queues[map->len++] = index;
1974 if (numa_node_id == -2)
1975 numa_node_id = cpu_to_node(cpu);
1976 else if (numa_node_id != cpu_to_node(cpu))
1979 } else if (dev_maps) {
1980 /* fill in the new device map from the old device map */
1981 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1982 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1987 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1989 /* Cleanup old maps */
1991 for_each_possible_cpu(cpu) {
1992 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1993 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1994 if (map && map != new_map)
1995 kfree_rcu(map, rcu);
1998 kfree_rcu(dev_maps, rcu);
2001 dev_maps = new_dev_maps;
2005 /* update Tx queue numa node */
2006 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2007 (numa_node_id >= 0) ? numa_node_id :
2013 /* removes queue from unused CPUs */
2014 for_each_possible_cpu(cpu) {
2015 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2018 if (remove_xps_queue(dev_maps, cpu, index))
2022 /* free map if not active */
2024 RCU_INIT_POINTER(dev->xps_maps, NULL);
2025 kfree_rcu(dev_maps, rcu);
2029 mutex_unlock(&xps_map_mutex);
2033 /* remove any maps that we added */
2034 for_each_possible_cpu(cpu) {
2035 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2036 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2038 if (new_map && new_map != map)
2042 mutex_unlock(&xps_map_mutex);
2044 kfree(new_dev_maps);
2047 EXPORT_SYMBOL(netif_set_xps_queue);
2051 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2052 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2054 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2058 if (txq < 1 || txq > dev->num_tx_queues)
2061 if (dev->reg_state == NETREG_REGISTERED ||
2062 dev->reg_state == NETREG_UNREGISTERING) {
2065 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2071 netif_setup_tc(dev, txq);
2073 if (txq < dev->real_num_tx_queues) {
2074 qdisc_reset_all_tx_gt(dev, txq);
2076 netif_reset_xps_queues_gt(dev, txq);
2081 dev->real_num_tx_queues = txq;
2084 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2088 * netif_set_real_num_rx_queues - set actual number of RX queues used
2089 * @dev: Network device
2090 * @rxq: Actual number of RX queues
2092 * This must be called either with the rtnl_lock held or before
2093 * registration of the net device. Returns 0 on success, or a
2094 * negative error code. If called before registration, it always
2097 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2101 if (rxq < 1 || rxq > dev->num_rx_queues)
2104 if (dev->reg_state == NETREG_REGISTERED) {
2107 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2113 dev->real_num_rx_queues = rxq;
2116 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2120 * netif_get_num_default_rss_queues - default number of RSS queues
2122 * This routine should set an upper limit on the number of RSS queues
2123 * used by default by multiqueue devices.
2125 int netif_get_num_default_rss_queues(void)
2127 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2129 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2131 static inline void __netif_reschedule(struct Qdisc *q)
2133 struct softnet_data *sd;
2134 unsigned long flags;
2136 local_irq_save(flags);
2137 sd = &__get_cpu_var(softnet_data);
2138 q->next_sched = NULL;
2139 *sd->output_queue_tailp = q;
2140 sd->output_queue_tailp = &q->next_sched;
2141 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2142 local_irq_restore(flags);
2145 void __netif_schedule(struct Qdisc *q)
2147 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2148 __netif_reschedule(q);
2150 EXPORT_SYMBOL(__netif_schedule);
2152 struct dev_kfree_skb_cb {
2153 enum skb_free_reason reason;
2156 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2158 return (struct dev_kfree_skb_cb *)skb->cb;
2161 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2163 unsigned long flags;
2165 if (likely(atomic_read(&skb->users) == 1)) {
2167 atomic_set(&skb->users, 0);
2168 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2171 get_kfree_skb_cb(skb)->reason = reason;
2172 local_irq_save(flags);
2173 skb->next = __this_cpu_read(softnet_data.completion_queue);
2174 __this_cpu_write(softnet_data.completion_queue, skb);
2175 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2176 local_irq_restore(flags);
2178 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2180 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2182 if (in_irq() || irqs_disabled())
2183 __dev_kfree_skb_irq(skb, reason);
2187 EXPORT_SYMBOL(__dev_kfree_skb_any);
2191 * netif_device_detach - mark device as removed
2192 * @dev: network device
2194 * Mark device as removed from system and therefore no longer available.
2196 void netif_device_detach(struct net_device *dev)
2198 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2199 netif_running(dev)) {
2200 netif_tx_stop_all_queues(dev);
2203 EXPORT_SYMBOL(netif_device_detach);
2206 * netif_device_attach - mark device as attached
2207 * @dev: network device
2209 * Mark device as attached from system and restart if needed.
2211 void netif_device_attach(struct net_device *dev)
2213 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2214 netif_running(dev)) {
2215 netif_tx_wake_all_queues(dev);
2216 __netdev_watchdog_up(dev);
2219 EXPORT_SYMBOL(netif_device_attach);
2221 static void skb_warn_bad_offload(const struct sk_buff *skb)
2223 static const netdev_features_t null_features = 0;
2224 struct net_device *dev = skb->dev;
2225 const char *driver = "";
2227 if (!net_ratelimit())
2230 if (dev && dev->dev.parent)
2231 driver = dev_driver_string(dev->dev.parent);
2233 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2234 "gso_type=%d ip_summed=%d\n",
2235 driver, dev ? &dev->features : &null_features,
2236 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2237 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2238 skb_shinfo(skb)->gso_type, skb->ip_summed);
2242 * Invalidate hardware checksum when packet is to be mangled, and
2243 * complete checksum manually on outgoing path.
2245 int skb_checksum_help(struct sk_buff *skb)
2248 int ret = 0, offset;
2250 if (skb->ip_summed == CHECKSUM_COMPLETE)
2251 goto out_set_summed;
2253 if (unlikely(skb_shinfo(skb)->gso_size)) {
2254 skb_warn_bad_offload(skb);
2258 /* Before computing a checksum, we should make sure no frag could
2259 * be modified by an external entity : checksum could be wrong.
2261 if (skb_has_shared_frag(skb)) {
2262 ret = __skb_linearize(skb);
2267 offset = skb_checksum_start_offset(skb);
2268 BUG_ON(offset >= skb_headlen(skb));
2269 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2271 offset += skb->csum_offset;
2272 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2274 if (skb_cloned(skb) &&
2275 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2276 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2281 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2283 skb->ip_summed = CHECKSUM_NONE;
2287 EXPORT_SYMBOL(skb_checksum_help);
2289 __be16 skb_network_protocol(struct sk_buff *skb)
2291 __be16 type = skb->protocol;
2292 int vlan_depth = ETH_HLEN;
2294 /* Tunnel gso handlers can set protocol to ethernet. */
2295 if (type == htons(ETH_P_TEB)) {
2298 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2301 eth = (struct ethhdr *)skb_mac_header(skb);
2302 type = eth->h_proto;
2305 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2306 struct vlan_hdr *vh;
2308 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2311 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2312 type = vh->h_vlan_encapsulated_proto;
2313 vlan_depth += VLAN_HLEN;
2320 * skb_mac_gso_segment - mac layer segmentation handler.
2321 * @skb: buffer to segment
2322 * @features: features for the output path (see dev->features)
2324 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2325 netdev_features_t features)
2327 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2328 struct packet_offload *ptype;
2329 __be16 type = skb_network_protocol(skb);
2331 if (unlikely(!type))
2332 return ERR_PTR(-EINVAL);
2334 __skb_pull(skb, skb->mac_len);
2337 list_for_each_entry_rcu(ptype, &offload_base, list) {
2338 if (ptype->type == type && ptype->callbacks.gso_segment) {
2339 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2342 err = ptype->callbacks.gso_send_check(skb);
2343 segs = ERR_PTR(err);
2344 if (err || skb_gso_ok(skb, features))
2346 __skb_push(skb, (skb->data -
2347 skb_network_header(skb)));
2349 segs = ptype->callbacks.gso_segment(skb, features);
2355 __skb_push(skb, skb->data - skb_mac_header(skb));
2359 EXPORT_SYMBOL(skb_mac_gso_segment);
2362 /* openvswitch calls this on rx path, so we need a different check.
2364 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2367 return skb->ip_summed != CHECKSUM_PARTIAL;
2369 return skb->ip_summed == CHECKSUM_NONE;
2373 * __skb_gso_segment - Perform segmentation on skb.
2374 * @skb: buffer to segment
2375 * @features: features for the output path (see dev->features)
2376 * @tx_path: whether it is called in TX path
2378 * This function segments the given skb and returns a list of segments.
2380 * It may return NULL if the skb requires no segmentation. This is
2381 * only possible when GSO is used for verifying header integrity.
2383 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2384 netdev_features_t features, bool tx_path)
2386 if (unlikely(skb_needs_check(skb, tx_path))) {
2389 skb_warn_bad_offload(skb);
2391 if (skb_header_cloned(skb) &&
2392 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2393 return ERR_PTR(err);
2396 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2397 SKB_GSO_CB(skb)->encap_level = 0;
2399 skb_reset_mac_header(skb);
2400 skb_reset_mac_len(skb);
2402 return skb_mac_gso_segment(skb, features);
2404 EXPORT_SYMBOL(__skb_gso_segment);
2406 /* Take action when hardware reception checksum errors are detected. */
2408 void netdev_rx_csum_fault(struct net_device *dev)
2410 if (net_ratelimit()) {
2411 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2415 EXPORT_SYMBOL(netdev_rx_csum_fault);
2418 /* Actually, we should eliminate this check as soon as we know, that:
2419 * 1. IOMMU is present and allows to map all the memory.
2420 * 2. No high memory really exists on this machine.
2423 static int illegal_highdma(const struct net_device *dev, struct sk_buff *skb)
2425 #ifdef CONFIG_HIGHMEM
2427 if (!(dev->features & NETIF_F_HIGHDMA)) {
2428 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2429 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2430 if (PageHighMem(skb_frag_page(frag)))
2435 if (PCI_DMA_BUS_IS_PHYS) {
2436 struct device *pdev = dev->dev.parent;
2440 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2441 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2442 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2443 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2452 void (*destructor)(struct sk_buff *skb);
2455 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2457 static void dev_gso_skb_destructor(struct sk_buff *skb)
2459 struct dev_gso_cb *cb;
2461 kfree_skb_list(skb->next);
2464 cb = DEV_GSO_CB(skb);
2466 cb->destructor(skb);
2470 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2471 * @skb: buffer to segment
2472 * @features: device features as applicable to this skb
2474 * This function segments the given skb and stores the list of segments
2477 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2479 struct sk_buff *segs;
2481 segs = skb_gso_segment(skb, features);
2483 /* Verifying header integrity only. */
2488 return PTR_ERR(segs);
2491 DEV_GSO_CB(skb)->destructor = skb->destructor;
2492 skb->destructor = dev_gso_skb_destructor;
2497 static netdev_features_t harmonize_features(struct sk_buff *skb,
2498 const struct net_device *dev,
2499 netdev_features_t features)
2501 if (skb->ip_summed != CHECKSUM_NONE &&
2502 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2503 features &= ~NETIF_F_ALL_CSUM;
2504 } else if (illegal_highdma(dev, skb)) {
2505 features &= ~NETIF_F_SG;
2511 netdev_features_t netif_skb_dev_features(struct sk_buff *skb,
2512 const struct net_device *dev)
2514 __be16 protocol = skb->protocol;
2515 netdev_features_t features = dev->features;
2517 if (skb_shinfo(skb)->gso_segs > dev->gso_max_segs)
2518 features &= ~NETIF_F_GSO_MASK;
2520 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2521 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2522 protocol = veh->h_vlan_encapsulated_proto;
2523 } else if (!vlan_tx_tag_present(skb)) {
2524 return harmonize_features(skb, dev, features);
2527 features &= (dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2528 NETIF_F_HW_VLAN_STAG_TX);
2530 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2531 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2532 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2533 NETIF_F_HW_VLAN_STAG_TX;
2535 return harmonize_features(skb, dev, features);
2537 EXPORT_SYMBOL(netif_skb_dev_features);
2539 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2540 struct netdev_queue *txq)
2542 const struct net_device_ops *ops = dev->netdev_ops;
2543 int rc = NETDEV_TX_OK;
2544 unsigned int skb_len;
2546 if (likely(!skb->next)) {
2547 netdev_features_t features;
2550 * If device doesn't need skb->dst, release it right now while
2551 * its hot in this cpu cache
2553 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2556 features = netif_skb_features(skb);
2558 if (vlan_tx_tag_present(skb) &&
2559 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2560 skb = __vlan_put_tag(skb, skb->vlan_proto,
2561 vlan_tx_tag_get(skb));
2568 /* If encapsulation offload request, verify we are testing
2569 * hardware encapsulation features instead of standard
2570 * features for the netdev
2572 if (skb->encapsulation)
2573 features &= dev->hw_enc_features;
2575 if (netif_needs_gso(skb, features)) {
2576 if (unlikely(dev_gso_segment(skb, features)))
2581 if (skb_needs_linearize(skb, features) &&
2582 __skb_linearize(skb))
2585 /* If packet is not checksummed and device does not
2586 * support checksumming for this protocol, complete
2587 * checksumming here.
2589 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2590 if (skb->encapsulation)
2591 skb_set_inner_transport_header(skb,
2592 skb_checksum_start_offset(skb));
2594 skb_set_transport_header(skb,
2595 skb_checksum_start_offset(skb));
2596 if (!(features & NETIF_F_ALL_CSUM) &&
2597 skb_checksum_help(skb))
2602 if (!list_empty(&ptype_all))
2603 dev_queue_xmit_nit(skb, dev);
2606 trace_net_dev_start_xmit(skb, dev);
2607 rc = ops->ndo_start_xmit(skb, dev);
2608 trace_net_dev_xmit(skb, rc, dev, skb_len);
2609 if (rc == NETDEV_TX_OK)
2610 txq_trans_update(txq);
2616 struct sk_buff *nskb = skb->next;
2618 skb->next = nskb->next;
2621 if (!list_empty(&ptype_all))
2622 dev_queue_xmit_nit(nskb, dev);
2624 skb_len = nskb->len;
2625 trace_net_dev_start_xmit(nskb, dev);
2626 rc = ops->ndo_start_xmit(nskb, dev);
2627 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2628 if (unlikely(rc != NETDEV_TX_OK)) {
2629 if (rc & ~NETDEV_TX_MASK)
2630 goto out_kfree_gso_skb;
2631 nskb->next = skb->next;
2635 txq_trans_update(txq);
2636 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2637 return NETDEV_TX_BUSY;
2638 } while (skb->next);
2641 if (likely(skb->next == NULL)) {
2642 skb->destructor = DEV_GSO_CB(skb)->destructor;
2651 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2653 static void qdisc_pkt_len_init(struct sk_buff *skb)
2655 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2657 qdisc_skb_cb(skb)->pkt_len = skb->len;
2659 /* To get more precise estimation of bytes sent on wire,
2660 * we add to pkt_len the headers size of all segments
2662 if (shinfo->gso_size) {
2663 unsigned int hdr_len;
2664 u16 gso_segs = shinfo->gso_segs;
2666 /* mac layer + network layer */
2667 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2669 /* + transport layer */
2670 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2671 hdr_len += tcp_hdrlen(skb);
2673 hdr_len += sizeof(struct udphdr);
2675 if (shinfo->gso_type & SKB_GSO_DODGY)
2676 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2679 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2683 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2684 struct net_device *dev,
2685 struct netdev_queue *txq)
2687 spinlock_t *root_lock = qdisc_lock(q);
2691 qdisc_pkt_len_init(skb);
2692 qdisc_calculate_pkt_len(skb, q);
2694 * Heuristic to force contended enqueues to serialize on a
2695 * separate lock before trying to get qdisc main lock.
2696 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2697 * and dequeue packets faster.
2699 contended = qdisc_is_running(q);
2700 if (unlikely(contended))
2701 spin_lock(&q->busylock);
2703 spin_lock(root_lock);
2704 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2707 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2708 qdisc_run_begin(q)) {
2710 * This is a work-conserving queue; there are no old skbs
2711 * waiting to be sent out; and the qdisc is not running -
2712 * xmit the skb directly.
2714 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2717 qdisc_bstats_update(q, skb);
2719 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2720 if (unlikely(contended)) {
2721 spin_unlock(&q->busylock);
2728 rc = NET_XMIT_SUCCESS;
2731 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2732 if (qdisc_run_begin(q)) {
2733 if (unlikely(contended)) {
2734 spin_unlock(&q->busylock);
2740 spin_unlock(root_lock);
2741 if (unlikely(contended))
2742 spin_unlock(&q->busylock);
2746 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2747 static void skb_update_prio(struct sk_buff *skb)
2749 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2751 if (!skb->priority && skb->sk && map) {
2752 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2754 if (prioidx < map->priomap_len)
2755 skb->priority = map->priomap[prioidx];
2759 #define skb_update_prio(skb)
2762 static DEFINE_PER_CPU(int, xmit_recursion);
2763 #define RECURSION_LIMIT 10
2766 * dev_loopback_xmit - loop back @skb
2767 * @skb: buffer to transmit
2769 int dev_loopback_xmit(struct sk_buff *skb)
2771 skb_reset_mac_header(skb);
2772 __skb_pull(skb, skb_network_offset(skb));
2773 skb->pkt_type = PACKET_LOOPBACK;
2774 skb->ip_summed = CHECKSUM_UNNECESSARY;
2775 WARN_ON(!skb_dst(skb));
2780 EXPORT_SYMBOL(dev_loopback_xmit);
2783 * __dev_queue_xmit - transmit a buffer
2784 * @skb: buffer to transmit
2785 * @accel_priv: private data used for L2 forwarding offload
2787 * Queue a buffer for transmission to a network device. The caller must
2788 * have set the device and priority and built the buffer before calling
2789 * this function. The function can be called from an interrupt.
2791 * A negative errno code is returned on a failure. A success does not
2792 * guarantee the frame will be transmitted as it may be dropped due
2793 * to congestion or traffic shaping.
2795 * -----------------------------------------------------------------------------------
2796 * I notice this method can also return errors from the queue disciplines,
2797 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2800 * Regardless of the return value, the skb is consumed, so it is currently
2801 * difficult to retry a send to this method. (You can bump the ref count
2802 * before sending to hold a reference for retry if you are careful.)
2804 * When calling this method, interrupts MUST be enabled. This is because
2805 * the BH enable code must have IRQs enabled so that it will not deadlock.
2808 static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
2810 struct net_device *dev = skb->dev;
2811 struct netdev_queue *txq;
2815 skb_reset_mac_header(skb);
2817 /* Disable soft irqs for various locks below. Also
2818 * stops preemption for RCU.
2822 skb_update_prio(skb);
2824 txq = netdev_pick_tx(dev, skb, accel_priv);
2825 q = rcu_dereference_bh(txq->qdisc);
2827 #ifdef CONFIG_NET_CLS_ACT
2828 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2830 trace_net_dev_queue(skb);
2832 rc = __dev_xmit_skb(skb, q, dev, txq);
2836 /* The device has no queue. Common case for software devices:
2837 loopback, all the sorts of tunnels...
2839 Really, it is unlikely that netif_tx_lock protection is necessary
2840 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2842 However, it is possible, that they rely on protection
2845 Check this and shot the lock. It is not prone from deadlocks.
2846 Either shot noqueue qdisc, it is even simpler 8)
2848 if (dev->flags & IFF_UP) {
2849 int cpu = smp_processor_id(); /* ok because BHs are off */
2851 if (txq->xmit_lock_owner != cpu) {
2853 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2854 goto recursion_alert;
2856 HARD_TX_LOCK(dev, txq, cpu);
2858 if (!netif_xmit_stopped(txq)) {
2859 __this_cpu_inc(xmit_recursion);
2860 rc = dev_hard_start_xmit(skb, dev, txq);
2861 __this_cpu_dec(xmit_recursion);
2862 if (dev_xmit_complete(rc)) {
2863 HARD_TX_UNLOCK(dev, txq);
2867 HARD_TX_UNLOCK(dev, txq);
2868 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2871 /* Recursion is detected! It is possible,
2875 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2881 rcu_read_unlock_bh();
2883 atomic_long_inc(&dev->tx_dropped);
2887 rcu_read_unlock_bh();
2891 int dev_queue_xmit(struct sk_buff *skb)
2893 return __dev_queue_xmit(skb, NULL);
2895 EXPORT_SYMBOL(dev_queue_xmit);
2897 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2899 return __dev_queue_xmit(skb, accel_priv);
2901 EXPORT_SYMBOL(dev_queue_xmit_accel);
2904 /*=======================================================================
2906 =======================================================================*/
2908 int netdev_max_backlog __read_mostly = 1000;
2909 EXPORT_SYMBOL(netdev_max_backlog);
2911 int netdev_tstamp_prequeue __read_mostly = 1;
2912 int netdev_budget __read_mostly = 300;
2913 int weight_p __read_mostly = 64; /* old backlog weight */
2915 /* Called with irq disabled */
2916 static inline void ____napi_schedule(struct softnet_data *sd,
2917 struct napi_struct *napi)
2919 list_add_tail(&napi->poll_list, &sd->poll_list);
2920 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2925 /* One global table that all flow-based protocols share. */
2926 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2927 EXPORT_SYMBOL(rps_sock_flow_table);
2929 struct static_key rps_needed __read_mostly;
2931 static struct rps_dev_flow *
2932 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2933 struct rps_dev_flow *rflow, u16 next_cpu)
2935 if (next_cpu != RPS_NO_CPU) {
2936 #ifdef CONFIG_RFS_ACCEL
2937 struct netdev_rx_queue *rxqueue;
2938 struct rps_dev_flow_table *flow_table;
2939 struct rps_dev_flow *old_rflow;
2944 /* Should we steer this flow to a different hardware queue? */
2945 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2946 !(dev->features & NETIF_F_NTUPLE))
2948 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2949 if (rxq_index == skb_get_rx_queue(skb))
2952 rxqueue = dev->_rx + rxq_index;
2953 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2956 flow_id = skb_get_hash(skb) & flow_table->mask;
2957 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2958 rxq_index, flow_id);
2962 rflow = &flow_table->flows[flow_id];
2964 if (old_rflow->filter == rflow->filter)
2965 old_rflow->filter = RPS_NO_FILTER;
2969 per_cpu(softnet_data, next_cpu).input_queue_head;
2972 rflow->cpu = next_cpu;
2977 * get_rps_cpu is called from netif_receive_skb and returns the target
2978 * CPU from the RPS map of the receiving queue for a given skb.
2979 * rcu_read_lock must be held on entry.
2981 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2982 struct rps_dev_flow **rflowp)
2984 struct netdev_rx_queue *rxqueue;
2985 struct rps_map *map;
2986 struct rps_dev_flow_table *flow_table;
2987 struct rps_sock_flow_table *sock_flow_table;
2992 if (skb_rx_queue_recorded(skb)) {
2993 u16 index = skb_get_rx_queue(skb);
2994 if (unlikely(index >= dev->real_num_rx_queues)) {
2995 WARN_ONCE(dev->real_num_rx_queues > 1,
2996 "%s received packet on queue %u, but number "
2997 "of RX queues is %u\n",
2998 dev->name, index, dev->real_num_rx_queues);
3001 rxqueue = dev->_rx + index;
3005 map = rcu_dereference(rxqueue->rps_map);
3007 if (map->len == 1 &&
3008 !rcu_access_pointer(rxqueue->rps_flow_table)) {
3009 tcpu = map->cpus[0];
3010 if (cpu_online(tcpu))
3014 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3018 skb_reset_network_header(skb);
3019 hash = skb_get_hash(skb);
3023 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3024 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3025 if (flow_table && sock_flow_table) {
3027 struct rps_dev_flow *rflow;
3029 rflow = &flow_table->flows[hash & flow_table->mask];
3032 next_cpu = sock_flow_table->ents[hash & sock_flow_table->mask];
3035 * If the desired CPU (where last recvmsg was done) is
3036 * different from current CPU (one in the rx-queue flow
3037 * table entry), switch if one of the following holds:
3038 * - Current CPU is unset (equal to RPS_NO_CPU).
3039 * - Current CPU is offline.
3040 * - The current CPU's queue tail has advanced beyond the
3041 * last packet that was enqueued using this table entry.
3042 * This guarantees that all previous packets for the flow
3043 * have been dequeued, thus preserving in order delivery.
3045 if (unlikely(tcpu != next_cpu) &&
3046 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3047 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3048 rflow->last_qtail)) >= 0)) {
3050 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3053 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3061 tcpu = map->cpus[((u64) hash * map->len) >> 32];
3063 if (cpu_online(tcpu)) {
3073 #ifdef CONFIG_RFS_ACCEL
3076 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3077 * @dev: Device on which the filter was set
3078 * @rxq_index: RX queue index
3079 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3080 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3082 * Drivers that implement ndo_rx_flow_steer() should periodically call
3083 * this function for each installed filter and remove the filters for
3084 * which it returns %true.
3086 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3087 u32 flow_id, u16 filter_id)
3089 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3090 struct rps_dev_flow_table *flow_table;
3091 struct rps_dev_flow *rflow;
3096 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3097 if (flow_table && flow_id <= flow_table->mask) {
3098 rflow = &flow_table->flows[flow_id];
3099 cpu = ACCESS_ONCE(rflow->cpu);
3100 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3101 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3102 rflow->last_qtail) <
3103 (int)(10 * flow_table->mask)))
3109 EXPORT_SYMBOL(rps_may_expire_flow);
3111 #endif /* CONFIG_RFS_ACCEL */
3113 /* Called from hardirq (IPI) context */
3114 static void rps_trigger_softirq(void *data)
3116 struct softnet_data *sd = data;
3118 ____napi_schedule(sd, &sd->backlog);
3122 #endif /* CONFIG_RPS */
3125 * Check if this softnet_data structure is another cpu one
3126 * If yes, queue it to our IPI list and return 1
3129 static int rps_ipi_queued(struct softnet_data *sd)
3132 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3135 sd->rps_ipi_next = mysd->rps_ipi_list;
3136 mysd->rps_ipi_list = sd;
3138 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3141 #endif /* CONFIG_RPS */
3145 #ifdef CONFIG_NET_FLOW_LIMIT
3146 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3149 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3151 #ifdef CONFIG_NET_FLOW_LIMIT
3152 struct sd_flow_limit *fl;
3153 struct softnet_data *sd;
3154 unsigned int old_flow, new_flow;
3156 if (qlen < (netdev_max_backlog >> 1))
3159 sd = &__get_cpu_var(softnet_data);
3162 fl = rcu_dereference(sd->flow_limit);
3164 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3165 old_flow = fl->history[fl->history_head];
3166 fl->history[fl->history_head] = new_flow;
3169 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3171 if (likely(fl->buckets[old_flow]))
3172 fl->buckets[old_flow]--;
3174 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3186 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3187 * queue (may be a remote CPU queue).
3189 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3190 unsigned int *qtail)
3192 struct softnet_data *sd;
3193 unsigned long flags;
3196 sd = &per_cpu(softnet_data, cpu);
3198 local_irq_save(flags);
3201 qlen = skb_queue_len(&sd->input_pkt_queue);
3202 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3203 if (skb_queue_len(&sd->input_pkt_queue)) {
3205 __skb_queue_tail(&sd->input_pkt_queue, skb);
3206 input_queue_tail_incr_save(sd, qtail);
3208 local_irq_restore(flags);
3209 return NET_RX_SUCCESS;
3212 /* Schedule NAPI for backlog device
3213 * We can use non atomic operation since we own the queue lock
3215 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3216 if (!rps_ipi_queued(sd))
3217 ____napi_schedule(sd, &sd->backlog);
3225 local_irq_restore(flags);
3227 atomic_long_inc(&skb->dev->rx_dropped);
3232 static int netif_rx_internal(struct sk_buff *skb)
3236 net_timestamp_check(netdev_tstamp_prequeue, skb);
3238 trace_netif_rx(skb);
3240 if (static_key_false(&rps_needed)) {
3241 struct rps_dev_flow voidflow, *rflow = &voidflow;
3247 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3249 cpu = smp_processor_id();
3251 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3259 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3266 * netif_rx - post buffer to the network code
3267 * @skb: buffer to post
3269 * This function receives a packet from a device driver and queues it for
3270 * the upper (protocol) levels to process. It always succeeds. The buffer
3271 * may be dropped during processing for congestion control or by the
3275 * NET_RX_SUCCESS (no congestion)
3276 * NET_RX_DROP (packet was dropped)
3280 int netif_rx(struct sk_buff *skb)
3282 trace_netif_rx_entry(skb);
3284 return netif_rx_internal(skb);
3286 EXPORT_SYMBOL(netif_rx);
3288 int netif_rx_ni(struct sk_buff *skb)
3292 trace_netif_rx_ni_entry(skb);
3295 err = netif_rx_internal(skb);
3296 if (local_softirq_pending())
3302 EXPORT_SYMBOL(netif_rx_ni);
3304 static void net_tx_action(struct softirq_action *h)
3306 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3308 if (sd->completion_queue) {
3309 struct sk_buff *clist;
3311 local_irq_disable();
3312 clist = sd->completion_queue;
3313 sd->completion_queue = NULL;
3317 struct sk_buff *skb = clist;
3318 clist = clist->next;
3320 WARN_ON(atomic_read(&skb->users));
3321 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3322 trace_consume_skb(skb);
3324 trace_kfree_skb(skb, net_tx_action);
3329 if (sd->output_queue) {
3332 local_irq_disable();
3333 head = sd->output_queue;
3334 sd->output_queue = NULL;
3335 sd->output_queue_tailp = &sd->output_queue;
3339 struct Qdisc *q = head;
3340 spinlock_t *root_lock;
3342 head = head->next_sched;
3344 root_lock = qdisc_lock(q);
3345 if (spin_trylock(root_lock)) {
3346 smp_mb__before_clear_bit();
3347 clear_bit(__QDISC_STATE_SCHED,
3350 spin_unlock(root_lock);
3352 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3354 __netif_reschedule(q);
3356 smp_mb__before_clear_bit();
3357 clear_bit(__QDISC_STATE_SCHED,
3365 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3366 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3367 /* This hook is defined here for ATM LANE */
3368 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3369 unsigned char *addr) __read_mostly;
3370 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3373 #ifdef CONFIG_NET_CLS_ACT
3374 /* TODO: Maybe we should just force sch_ingress to be compiled in
3375 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3376 * a compare and 2 stores extra right now if we dont have it on
3377 * but have CONFIG_NET_CLS_ACT
3378 * NOTE: This doesn't stop any functionality; if you dont have
3379 * the ingress scheduler, you just can't add policies on ingress.
3382 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3384 struct net_device *dev = skb->dev;
3385 u32 ttl = G_TC_RTTL(skb->tc_verd);
3386 int result = TC_ACT_OK;
3389 if (unlikely(MAX_RED_LOOP < ttl++)) {
3390 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3391 skb->skb_iif, dev->ifindex);
3395 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3396 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3399 if (q != &noop_qdisc) {
3400 spin_lock(qdisc_lock(q));
3401 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3402 result = qdisc_enqueue_root(skb, q);
3403 spin_unlock(qdisc_lock(q));
3409 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3410 struct packet_type **pt_prev,
3411 int *ret, struct net_device *orig_dev)
3413 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3415 if (!rxq || rxq->qdisc == &noop_qdisc)
3419 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3423 switch (ing_filter(skb, rxq)) {
3437 * netdev_rx_handler_register - register receive handler
3438 * @dev: device to register a handler for
3439 * @rx_handler: receive handler to register
3440 * @rx_handler_data: data pointer that is used by rx handler
3442 * Register a receive hander for a device. This handler will then be
3443 * called from __netif_receive_skb. A negative errno code is returned
3446 * The caller must hold the rtnl_mutex.
3448 * For a general description of rx_handler, see enum rx_handler_result.
3450 int netdev_rx_handler_register(struct net_device *dev,
3451 rx_handler_func_t *rx_handler,
3452 void *rx_handler_data)
3456 if (dev->rx_handler)
3459 /* Note: rx_handler_data must be set before rx_handler */
3460 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3461 rcu_assign_pointer(dev->rx_handler, rx_handler);
3465 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3468 * netdev_rx_handler_unregister - unregister receive handler
3469 * @dev: device to unregister a handler from
3471 * Unregister a receive handler from a device.
3473 * The caller must hold the rtnl_mutex.
3475 void netdev_rx_handler_unregister(struct net_device *dev)
3479 RCU_INIT_POINTER(dev->rx_handler, NULL);
3480 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3481 * section has a guarantee to see a non NULL rx_handler_data
3485 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3487 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3490 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3491 * the special handling of PFMEMALLOC skbs.
3493 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3495 switch (skb->protocol) {
3496 case htons(ETH_P_ARP):
3497 case htons(ETH_P_IP):
3498 case htons(ETH_P_IPV6):
3499 case htons(ETH_P_8021Q):
3500 case htons(ETH_P_8021AD):
3507 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3509 struct packet_type *ptype, *pt_prev;
3510 rx_handler_func_t *rx_handler;
3511 struct net_device *orig_dev;
3512 struct net_device *null_or_dev;
3513 bool deliver_exact = false;
3514 int ret = NET_RX_DROP;
3517 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3519 trace_netif_receive_skb(skb);
3521 orig_dev = skb->dev;
3523 skb_reset_network_header(skb);
3524 if (!skb_transport_header_was_set(skb))
3525 skb_reset_transport_header(skb);
3526 skb_reset_mac_len(skb);
3533 skb->skb_iif = skb->dev->ifindex;
3535 __this_cpu_inc(softnet_data.processed);
3537 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3538 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3539 skb = vlan_untag(skb);
3544 #ifdef CONFIG_NET_CLS_ACT
3545 if (skb->tc_verd & TC_NCLS) {
3546 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3554 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3555 if (!ptype->dev || ptype->dev == skb->dev) {
3557 ret = deliver_skb(skb, pt_prev, orig_dev);
3563 #ifdef CONFIG_NET_CLS_ACT
3564 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3570 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3573 if (vlan_tx_tag_present(skb)) {
3575 ret = deliver_skb(skb, pt_prev, orig_dev);
3578 if (vlan_do_receive(&skb))
3580 else if (unlikely(!skb))
3584 rx_handler = rcu_dereference(skb->dev->rx_handler);
3587 ret = deliver_skb(skb, pt_prev, orig_dev);
3590 switch (rx_handler(&skb)) {
3591 case RX_HANDLER_CONSUMED:
3592 ret = NET_RX_SUCCESS;
3594 case RX_HANDLER_ANOTHER:
3596 case RX_HANDLER_EXACT:
3597 deliver_exact = true;
3598 case RX_HANDLER_PASS:
3605 if (unlikely(vlan_tx_tag_present(skb))) {
3606 if (vlan_tx_tag_get_id(skb))
3607 skb->pkt_type = PACKET_OTHERHOST;
3608 /* Note: we might in the future use prio bits
3609 * and set skb->priority like in vlan_do_receive()
3610 * For the time being, just ignore Priority Code Point
3615 /* deliver only exact match when indicated */
3616 null_or_dev = deliver_exact ? skb->dev : NULL;
3618 type = skb->protocol;
3619 list_for_each_entry_rcu(ptype,
3620 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3621 if (ptype->type == type &&
3622 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3623 ptype->dev == orig_dev)) {
3625 ret = deliver_skb(skb, pt_prev, orig_dev);
3631 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3634 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3637 atomic_long_inc(&skb->dev->rx_dropped);
3639 /* Jamal, now you will not able to escape explaining
3640 * me how you were going to use this. :-)
3650 static int __netif_receive_skb(struct sk_buff *skb)
3654 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3655 unsigned long pflags = current->flags;
3658 * PFMEMALLOC skbs are special, they should
3659 * - be delivered to SOCK_MEMALLOC sockets only
3660 * - stay away from userspace
3661 * - have bounded memory usage
3663 * Use PF_MEMALLOC as this saves us from propagating the allocation
3664 * context down to all allocation sites.
3666 current->flags |= PF_MEMALLOC;
3667 ret = __netif_receive_skb_core(skb, true);
3668 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3670 ret = __netif_receive_skb_core(skb, false);
3675 static int netif_receive_skb_internal(struct sk_buff *skb)
3677 net_timestamp_check(netdev_tstamp_prequeue, skb);
3679 if (skb_defer_rx_timestamp(skb))
3680 return NET_RX_SUCCESS;
3683 if (static_key_false(&rps_needed)) {
3684 struct rps_dev_flow voidflow, *rflow = &voidflow;
3689 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3692 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3699 return __netif_receive_skb(skb);
3703 * netif_receive_skb - process receive buffer from network
3704 * @skb: buffer to process
3706 * netif_receive_skb() is the main receive data processing function.
3707 * It always succeeds. The buffer may be dropped during processing
3708 * for congestion control or by the protocol layers.
3710 * This function may only be called from softirq context and interrupts
3711 * should be enabled.
3713 * Return values (usually ignored):
3714 * NET_RX_SUCCESS: no congestion
3715 * NET_RX_DROP: packet was dropped
3717 int netif_receive_skb(struct sk_buff *skb)
3719 trace_netif_receive_skb_entry(skb);
3721 return netif_receive_skb_internal(skb);
3723 EXPORT_SYMBOL(netif_receive_skb);
3725 /* Network device is going away, flush any packets still pending
3726 * Called with irqs disabled.
3728 static void flush_backlog(void *arg)
3730 struct net_device *dev = arg;
3731 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3732 struct sk_buff *skb, *tmp;
3735 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3736 if (skb->dev == dev) {
3737 __skb_unlink(skb, &sd->input_pkt_queue);
3739 input_queue_head_incr(sd);
3744 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3745 if (skb->dev == dev) {
3746 __skb_unlink(skb, &sd->process_queue);
3748 input_queue_head_incr(sd);
3753 static int napi_gro_complete(struct sk_buff *skb)
3755 struct packet_offload *ptype;
3756 __be16 type = skb->protocol;
3757 struct list_head *head = &offload_base;
3760 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3762 if (NAPI_GRO_CB(skb)->count == 1) {
3763 skb_shinfo(skb)->gso_size = 0;
3768 list_for_each_entry_rcu(ptype, head, list) {
3769 if (ptype->type != type || !ptype->callbacks.gro_complete)
3772 err = ptype->callbacks.gro_complete(skb, 0);
3778 WARN_ON(&ptype->list == head);
3780 return NET_RX_SUCCESS;
3784 return netif_receive_skb_internal(skb);
3787 /* napi->gro_list contains packets ordered by age.
3788 * youngest packets at the head of it.
3789 * Complete skbs in reverse order to reduce latencies.
3791 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3793 struct sk_buff *skb, *prev = NULL;
3795 /* scan list and build reverse chain */
3796 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3801 for (skb = prev; skb; skb = prev) {
3804 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3808 napi_gro_complete(skb);
3812 napi->gro_list = NULL;
3814 EXPORT_SYMBOL(napi_gro_flush);
3816 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3819 unsigned int maclen = skb->dev->hard_header_len;
3820 u32 hash = skb_get_hash_raw(skb);
3822 for (p = napi->gro_list; p; p = p->next) {
3823 unsigned long diffs;
3825 NAPI_GRO_CB(p)->flush = 0;
3827 if (hash != skb_get_hash_raw(p)) {
3828 NAPI_GRO_CB(p)->same_flow = 0;
3832 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3833 diffs |= p->vlan_tci ^ skb->vlan_tci;
3834 if (maclen == ETH_HLEN)
3835 diffs |= compare_ether_header(skb_mac_header(p),
3836 skb_gro_mac_header(skb));
3838 diffs = memcmp(skb_mac_header(p),
3839 skb_gro_mac_header(skb),
3841 NAPI_GRO_CB(p)->same_flow = !diffs;
3845 static void skb_gro_reset_offset(struct sk_buff *skb)
3847 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3848 const skb_frag_t *frag0 = &pinfo->frags[0];
3850 NAPI_GRO_CB(skb)->data_offset = 0;
3851 NAPI_GRO_CB(skb)->frag0 = NULL;
3852 NAPI_GRO_CB(skb)->frag0_len = 0;
3854 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3856 !PageHighMem(skb_frag_page(frag0))) {
3857 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3858 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3862 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3864 struct sk_buff **pp = NULL;
3865 struct packet_offload *ptype;
3866 __be16 type = skb->protocol;
3867 struct list_head *head = &offload_base;
3869 enum gro_result ret;
3871 if (!(skb->dev->features & NETIF_F_GRO))
3874 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3877 skb_gro_reset_offset(skb);
3878 gro_list_prepare(napi, skb);
3879 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3882 list_for_each_entry_rcu(ptype, head, list) {
3883 if (ptype->type != type || !ptype->callbacks.gro_receive)
3886 skb_set_network_header(skb, skb_gro_offset(skb));
3887 skb_reset_mac_len(skb);
3888 NAPI_GRO_CB(skb)->same_flow = 0;
3889 NAPI_GRO_CB(skb)->flush = 0;
3890 NAPI_GRO_CB(skb)->free = 0;
3891 NAPI_GRO_CB(skb)->udp_mark = 0;
3893 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3898 if (&ptype->list == head)
3901 same_flow = NAPI_GRO_CB(skb)->same_flow;
3902 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3905 struct sk_buff *nskb = *pp;
3909 napi_gro_complete(nskb);
3916 if (NAPI_GRO_CB(skb)->flush)
3919 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
3920 struct sk_buff *nskb = napi->gro_list;
3922 /* locate the end of the list to select the 'oldest' flow */
3923 while (nskb->next) {
3929 napi_gro_complete(nskb);
3933 NAPI_GRO_CB(skb)->count = 1;
3934 NAPI_GRO_CB(skb)->age = jiffies;
3935 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3936 skb->next = napi->gro_list;
3937 napi->gro_list = skb;
3941 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3942 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3944 BUG_ON(skb->end - skb->tail < grow);
3946 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3949 skb->data_len -= grow;
3951 skb_shinfo(skb)->frags[0].page_offset += grow;
3952 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3954 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3955 skb_frag_unref(skb, 0);
3956 memmove(skb_shinfo(skb)->frags,
3957 skb_shinfo(skb)->frags + 1,
3958 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3970 struct packet_offload *gro_find_receive_by_type(__be16 type)
3972 struct list_head *offload_head = &offload_base;
3973 struct packet_offload *ptype;
3975 list_for_each_entry_rcu(ptype, offload_head, list) {
3976 if (ptype->type != type || !ptype->callbacks.gro_receive)
3982 EXPORT_SYMBOL(gro_find_receive_by_type);
3984 struct packet_offload *gro_find_complete_by_type(__be16 type)
3986 struct list_head *offload_head = &offload_base;
3987 struct packet_offload *ptype;
3989 list_for_each_entry_rcu(ptype, offload_head, list) {
3990 if (ptype->type != type || !ptype->callbacks.gro_complete)
3996 EXPORT_SYMBOL(gro_find_complete_by_type);
3998 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4002 if (netif_receive_skb_internal(skb))
4010 case GRO_MERGED_FREE:
4011 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
4012 kmem_cache_free(skbuff_head_cache, skb);
4025 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4027 trace_napi_gro_receive_entry(skb);
4029 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4031 EXPORT_SYMBOL(napi_gro_receive);
4033 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4035 __skb_pull(skb, skb_headlen(skb));
4036 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4037 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4039 skb->dev = napi->dev;
4045 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4047 struct sk_buff *skb = napi->skb;
4050 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4055 EXPORT_SYMBOL(napi_get_frags);
4057 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
4062 if (netif_receive_skb_internal(skb))
4067 case GRO_MERGED_FREE:
4068 napi_reuse_skb(napi, skb);
4079 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4081 struct sk_buff *skb = napi->skb;
4085 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4086 napi_reuse_skb(napi, skb);
4089 skb->protocol = eth_type_trans(skb, skb->dev);
4094 gro_result_t napi_gro_frags(struct napi_struct *napi)
4096 struct sk_buff *skb = napi_frags_skb(napi);
4101 trace_napi_gro_frags_entry(skb);
4103 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4105 EXPORT_SYMBOL(napi_gro_frags);
4108 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4109 * Note: called with local irq disabled, but exits with local irq enabled.
4111 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4114 struct softnet_data *remsd = sd->rps_ipi_list;
4117 sd->rps_ipi_list = NULL;
4121 /* Send pending IPI's to kick RPS processing on remote cpus. */
4123 struct softnet_data *next = remsd->rps_ipi_next;
4125 if (cpu_online(remsd->cpu))
4126 __smp_call_function_single(remsd->cpu,
4135 static int process_backlog(struct napi_struct *napi, int quota)
4138 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4141 /* Check if we have pending ipi, its better to send them now,
4142 * not waiting net_rx_action() end.
4144 if (sd->rps_ipi_list) {
4145 local_irq_disable();
4146 net_rps_action_and_irq_enable(sd);
4149 napi->weight = weight_p;
4150 local_irq_disable();
4151 while (work < quota) {
4152 struct sk_buff *skb;
4155 while ((skb = __skb_dequeue(&sd->process_queue))) {
4157 __netif_receive_skb(skb);
4158 local_irq_disable();
4159 input_queue_head_incr(sd);
4160 if (++work >= quota) {
4167 qlen = skb_queue_len(&sd->input_pkt_queue);
4169 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4170 &sd->process_queue);
4172 if (qlen < quota - work) {
4174 * Inline a custom version of __napi_complete().
4175 * only current cpu owns and manipulates this napi,
4176 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4177 * we can use a plain write instead of clear_bit(),
4178 * and we dont need an smp_mb() memory barrier.
4180 list_del(&napi->poll_list);
4183 quota = work + qlen;
4193 * __napi_schedule - schedule for receive
4194 * @n: entry to schedule
4196 * The entry's receive function will be scheduled to run
4198 void __napi_schedule(struct napi_struct *n)
4200 unsigned long flags;
4202 local_irq_save(flags);
4203 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4204 local_irq_restore(flags);
4206 EXPORT_SYMBOL(__napi_schedule);
4208 void __napi_complete(struct napi_struct *n)
4210 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4211 BUG_ON(n->gro_list);
4213 list_del(&n->poll_list);
4214 smp_mb__before_clear_bit();
4215 clear_bit(NAPI_STATE_SCHED, &n->state);
4217 EXPORT_SYMBOL(__napi_complete);
4219 void napi_complete(struct napi_struct *n)
4221 unsigned long flags;
4224 * don't let napi dequeue from the cpu poll list
4225 * just in case its running on a different cpu
4227 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4230 napi_gro_flush(n, false);
4231 local_irq_save(flags);
4233 local_irq_restore(flags);
4235 EXPORT_SYMBOL(napi_complete);
4237 /* must be called under rcu_read_lock(), as we dont take a reference */
4238 struct napi_struct *napi_by_id(unsigned int napi_id)
4240 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4241 struct napi_struct *napi;
4243 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4244 if (napi->napi_id == napi_id)
4249 EXPORT_SYMBOL_GPL(napi_by_id);
4251 void napi_hash_add(struct napi_struct *napi)
4253 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4255 spin_lock(&napi_hash_lock);
4257 /* 0 is not a valid id, we also skip an id that is taken
4258 * we expect both events to be extremely rare
4261 while (!napi->napi_id) {
4262 napi->napi_id = ++napi_gen_id;
4263 if (napi_by_id(napi->napi_id))
4267 hlist_add_head_rcu(&napi->napi_hash_node,
4268 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4270 spin_unlock(&napi_hash_lock);
4273 EXPORT_SYMBOL_GPL(napi_hash_add);
4275 /* Warning : caller is responsible to make sure rcu grace period
4276 * is respected before freeing memory containing @napi
4278 void napi_hash_del(struct napi_struct *napi)
4280 spin_lock(&napi_hash_lock);
4282 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4283 hlist_del_rcu(&napi->napi_hash_node);
4285 spin_unlock(&napi_hash_lock);
4287 EXPORT_SYMBOL_GPL(napi_hash_del);
4289 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4290 int (*poll)(struct napi_struct *, int), int weight)
4292 INIT_LIST_HEAD(&napi->poll_list);
4293 napi->gro_count = 0;
4294 napi->gro_list = NULL;
4297 if (weight > NAPI_POLL_WEIGHT)
4298 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4300 napi->weight = weight;
4301 list_add(&napi->dev_list, &dev->napi_list);
4303 #ifdef CONFIG_NETPOLL
4304 spin_lock_init(&napi->poll_lock);
4305 napi->poll_owner = -1;
4307 set_bit(NAPI_STATE_SCHED, &napi->state);
4309 EXPORT_SYMBOL(netif_napi_add);
4311 void netif_napi_del(struct napi_struct *napi)
4313 list_del_init(&napi->dev_list);
4314 napi_free_frags(napi);
4316 kfree_skb_list(napi->gro_list);
4317 napi->gro_list = NULL;
4318 napi->gro_count = 0;
4320 EXPORT_SYMBOL(netif_napi_del);
4322 static void net_rx_action(struct softirq_action *h)
4324 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4325 unsigned long time_limit = jiffies + 2;
4326 int budget = netdev_budget;
4329 local_irq_disable();
4331 while (!list_empty(&sd->poll_list)) {
4332 struct napi_struct *n;
4335 /* If softirq window is exhuasted then punt.
4336 * Allow this to run for 2 jiffies since which will allow
4337 * an average latency of 1.5/HZ.
4339 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4344 /* Even though interrupts have been re-enabled, this
4345 * access is safe because interrupts can only add new
4346 * entries to the tail of this list, and only ->poll()
4347 * calls can remove this head entry from the list.
4349 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4351 have = netpoll_poll_lock(n);
4355 /* This NAPI_STATE_SCHED test is for avoiding a race
4356 * with netpoll's poll_napi(). Only the entity which
4357 * obtains the lock and sees NAPI_STATE_SCHED set will
4358 * actually make the ->poll() call. Therefore we avoid
4359 * accidentally calling ->poll() when NAPI is not scheduled.
4362 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4363 work = n->poll(n, weight);
4367 WARN_ON_ONCE(work > weight);
4371 local_irq_disable();
4373 /* Drivers must not modify the NAPI state if they
4374 * consume the entire weight. In such cases this code
4375 * still "owns" the NAPI instance and therefore can
4376 * move the instance around on the list at-will.
4378 if (unlikely(work == weight)) {
4379 if (unlikely(napi_disable_pending(n))) {
4382 local_irq_disable();
4385 /* flush too old packets
4386 * If HZ < 1000, flush all packets.
4389 napi_gro_flush(n, HZ >= 1000);
4390 local_irq_disable();
4392 list_move_tail(&n->poll_list, &sd->poll_list);
4396 netpoll_poll_unlock(have);
4399 net_rps_action_and_irq_enable(sd);
4401 #ifdef CONFIG_NET_DMA
4403 * There may not be any more sk_buffs coming right now, so push
4404 * any pending DMA copies to hardware
4406 dma_issue_pending_all();
4413 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4417 struct netdev_adjacent {
4418 struct net_device *dev;
4420 /* upper master flag, there can only be one master device per list */
4423 /* counter for the number of times this device was added to us */
4426 /* private field for the users */
4429 struct list_head list;
4430 struct rcu_head rcu;
4433 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4434 struct net_device *adj_dev,
4435 struct list_head *adj_list)
4437 struct netdev_adjacent *adj;
4439 list_for_each_entry(adj, adj_list, list) {
4440 if (adj->dev == adj_dev)
4447 * netdev_has_upper_dev - Check if device is linked to an upper device
4449 * @upper_dev: upper device to check
4451 * Find out if a device is linked to specified upper device and return true
4452 * in case it is. Note that this checks only immediate upper device,
4453 * not through a complete stack of devices. The caller must hold the RTNL lock.
4455 bool netdev_has_upper_dev(struct net_device *dev,
4456 struct net_device *upper_dev)
4460 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4462 EXPORT_SYMBOL(netdev_has_upper_dev);
4465 * netdev_has_any_upper_dev - Check if device is linked to some device
4468 * Find out if a device is linked to an upper device and return true in case
4469 * it is. The caller must hold the RTNL lock.
4471 static bool netdev_has_any_upper_dev(struct net_device *dev)
4475 return !list_empty(&dev->all_adj_list.upper);
4479 * netdev_master_upper_dev_get - Get master upper device
4482 * Find a master upper device and return pointer to it or NULL in case
4483 * it's not there. The caller must hold the RTNL lock.
4485 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4487 struct netdev_adjacent *upper;
4491 if (list_empty(&dev->adj_list.upper))
4494 upper = list_first_entry(&dev->adj_list.upper,
4495 struct netdev_adjacent, list);
4496 if (likely(upper->master))
4500 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4502 void *netdev_adjacent_get_private(struct list_head *adj_list)
4504 struct netdev_adjacent *adj;
4506 adj = list_entry(adj_list, struct netdev_adjacent, list);
4508 return adj->private;
4510 EXPORT_SYMBOL(netdev_adjacent_get_private);
4513 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4515 * @iter: list_head ** of the current position
4517 * Gets the next device from the dev's upper list, starting from iter
4518 * position. The caller must hold RCU read lock.
4520 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4521 struct list_head **iter)
4523 struct netdev_adjacent *upper;
4525 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4527 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4529 if (&upper->list == &dev->all_adj_list.upper)
4532 *iter = &upper->list;
4536 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4539 * netdev_lower_get_next_private - Get the next ->private from the
4540 * lower neighbour list
4542 * @iter: list_head ** of the current position
4544 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4545 * list, starting from iter position. The caller must hold either hold the
4546 * RTNL lock or its own locking that guarantees that the neighbour lower
4547 * list will remain unchainged.
4549 void *netdev_lower_get_next_private(struct net_device *dev,
4550 struct list_head **iter)
4552 struct netdev_adjacent *lower;
4554 lower = list_entry(*iter, struct netdev_adjacent, list);
4556 if (&lower->list == &dev->adj_list.lower)
4560 *iter = lower->list.next;
4562 return lower->private;
4564 EXPORT_SYMBOL(netdev_lower_get_next_private);
4567 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4568 * lower neighbour list, RCU
4571 * @iter: list_head ** of the current position
4573 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4574 * list, starting from iter position. The caller must hold RCU read lock.
4576 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4577 struct list_head **iter)
4579 struct netdev_adjacent *lower;
4581 WARN_ON_ONCE(!rcu_read_lock_held());
4583 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4585 if (&lower->list == &dev->adj_list.lower)
4589 *iter = &lower->list;
4591 return lower->private;
4593 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4596 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4597 * lower neighbour list, RCU
4601 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4602 * list. The caller must hold RCU read lock.
4604 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4606 struct netdev_adjacent *lower;
4608 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4609 struct netdev_adjacent, list);
4611 return lower->private;
4614 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4617 * netdev_master_upper_dev_get_rcu - Get master upper device
4620 * Find a master upper device and return pointer to it or NULL in case
4621 * it's not there. The caller must hold the RCU read lock.
4623 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4625 struct netdev_adjacent *upper;
4627 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4628 struct netdev_adjacent, list);
4629 if (upper && likely(upper->master))
4633 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4635 static int netdev_adjacent_sysfs_add(struct net_device *dev,
4636 struct net_device *adj_dev,
4637 struct list_head *dev_list)
4639 char linkname[IFNAMSIZ+7];
4640 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4641 "upper_%s" : "lower_%s", adj_dev->name);
4642 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
4645 static void netdev_adjacent_sysfs_del(struct net_device *dev,
4647 struct list_head *dev_list)
4649 char linkname[IFNAMSIZ+7];
4650 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4651 "upper_%s" : "lower_%s", name);
4652 sysfs_remove_link(&(dev->dev.kobj), linkname);
4655 #define netdev_adjacent_is_neigh_list(dev, dev_list) \
4656 (dev_list == &dev->adj_list.upper || \
4657 dev_list == &dev->adj_list.lower)
4659 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4660 struct net_device *adj_dev,
4661 struct list_head *dev_list,
4662 void *private, bool master)
4664 struct netdev_adjacent *adj;
4667 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4674 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4679 adj->master = master;
4681 adj->private = private;
4684 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4685 adj_dev->name, dev->name, adj_dev->name);
4687 if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
4688 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
4693 /* Ensure that master link is always the first item in list. */
4695 ret = sysfs_create_link(&(dev->dev.kobj),
4696 &(adj_dev->dev.kobj), "master");
4698 goto remove_symlinks;
4700 list_add_rcu(&adj->list, dev_list);
4702 list_add_tail_rcu(&adj->list, dev_list);
4708 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4709 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4717 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4718 struct net_device *adj_dev,
4719 struct list_head *dev_list)
4721 struct netdev_adjacent *adj;
4723 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4726 pr_err("tried to remove device %s from %s\n",
4727 dev->name, adj_dev->name);
4731 if (adj->ref_nr > 1) {
4732 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4739 sysfs_remove_link(&(dev->dev.kobj), "master");
4741 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4742 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4744 list_del_rcu(&adj->list);
4745 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4746 adj_dev->name, dev->name, adj_dev->name);
4748 kfree_rcu(adj, rcu);
4751 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4752 struct net_device *upper_dev,
4753 struct list_head *up_list,
4754 struct list_head *down_list,
4755 void *private, bool master)
4759 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4764 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4767 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4774 static int __netdev_adjacent_dev_link(struct net_device *dev,
4775 struct net_device *upper_dev)
4777 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4778 &dev->all_adj_list.upper,
4779 &upper_dev->all_adj_list.lower,
4783 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4784 struct net_device *upper_dev,
4785 struct list_head *up_list,
4786 struct list_head *down_list)
4788 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4789 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4792 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4793 struct net_device *upper_dev)
4795 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4796 &dev->all_adj_list.upper,
4797 &upper_dev->all_adj_list.lower);
4800 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4801 struct net_device *upper_dev,
4802 void *private, bool master)
4804 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4809 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4810 &dev->adj_list.upper,
4811 &upper_dev->adj_list.lower,
4814 __netdev_adjacent_dev_unlink(dev, upper_dev);
4821 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4822 struct net_device *upper_dev)
4824 __netdev_adjacent_dev_unlink(dev, upper_dev);
4825 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4826 &dev->adj_list.upper,
4827 &upper_dev->adj_list.lower);
4830 static int __netdev_upper_dev_link(struct net_device *dev,
4831 struct net_device *upper_dev, bool master,
4834 struct netdev_adjacent *i, *j, *to_i, *to_j;
4839 if (dev == upper_dev)
4842 /* To prevent loops, check if dev is not upper device to upper_dev. */
4843 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4846 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4849 if (master && netdev_master_upper_dev_get(dev))
4852 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4857 /* Now that we linked these devs, make all the upper_dev's
4858 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4859 * versa, and don't forget the devices itself. All of these
4860 * links are non-neighbours.
4862 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4863 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4864 pr_debug("Interlinking %s with %s, non-neighbour\n",
4865 i->dev->name, j->dev->name);
4866 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4872 /* add dev to every upper_dev's upper device */
4873 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4874 pr_debug("linking %s's upper device %s with %s\n",
4875 upper_dev->name, i->dev->name, dev->name);
4876 ret = __netdev_adjacent_dev_link(dev, i->dev);
4878 goto rollback_upper_mesh;
4881 /* add upper_dev to every dev's lower device */
4882 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4883 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4884 i->dev->name, upper_dev->name);
4885 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4887 goto rollback_lower_mesh;
4890 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4893 rollback_lower_mesh:
4895 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4898 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4903 rollback_upper_mesh:
4905 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4908 __netdev_adjacent_dev_unlink(dev, i->dev);
4916 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4917 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4918 if (i == to_i && j == to_j)
4920 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4926 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4932 * netdev_upper_dev_link - Add a link to the upper device
4934 * @upper_dev: new upper device
4936 * Adds a link to device which is upper to this one. The caller must hold
4937 * the RTNL lock. On a failure a negative errno code is returned.
4938 * On success the reference counts are adjusted and the function
4941 int netdev_upper_dev_link(struct net_device *dev,
4942 struct net_device *upper_dev)
4944 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4946 EXPORT_SYMBOL(netdev_upper_dev_link);
4949 * netdev_master_upper_dev_link - Add a master link to the upper device
4951 * @upper_dev: new upper device
4953 * Adds a link to device which is upper to this one. In this case, only
4954 * one master upper device can be linked, although other non-master devices
4955 * might be linked as well. The caller must hold the RTNL lock.
4956 * On a failure a negative errno code is returned. On success the reference
4957 * counts are adjusted and the function returns zero.
4959 int netdev_master_upper_dev_link(struct net_device *dev,
4960 struct net_device *upper_dev)
4962 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4964 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4966 int netdev_master_upper_dev_link_private(struct net_device *dev,
4967 struct net_device *upper_dev,
4970 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4972 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4975 * netdev_upper_dev_unlink - Removes a link to upper device
4977 * @upper_dev: new upper device
4979 * Removes a link to device which is upper to this one. The caller must hold
4982 void netdev_upper_dev_unlink(struct net_device *dev,
4983 struct net_device *upper_dev)
4985 struct netdev_adjacent *i, *j;
4988 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4990 /* Here is the tricky part. We must remove all dev's lower
4991 * devices from all upper_dev's upper devices and vice
4992 * versa, to maintain the graph relationship.
4994 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4995 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
4996 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4998 /* remove also the devices itself from lower/upper device
5001 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5002 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
5004 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5005 __netdev_adjacent_dev_unlink(dev, i->dev);
5007 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5009 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5011 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5013 struct netdev_adjacent *iter;
5015 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5016 netdev_adjacent_sysfs_del(iter->dev, oldname,
5017 &iter->dev->adj_list.lower);
5018 netdev_adjacent_sysfs_add(iter->dev, dev,
5019 &iter->dev->adj_list.lower);
5022 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5023 netdev_adjacent_sysfs_del(iter->dev, oldname,
5024 &iter->dev->adj_list.upper);
5025 netdev_adjacent_sysfs_add(iter->dev, dev,
5026 &iter->dev->adj_list.upper);
5030 void *netdev_lower_dev_get_private(struct net_device *dev,
5031 struct net_device *lower_dev)
5033 struct netdev_adjacent *lower;
5037 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
5041 return lower->private;
5043 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5045 static void dev_change_rx_flags(struct net_device *dev, int flags)
5047 const struct net_device_ops *ops = dev->netdev_ops;
5049 if (ops->ndo_change_rx_flags)
5050 ops->ndo_change_rx_flags(dev, flags);
5053 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5055 unsigned int old_flags = dev->flags;
5061 dev->flags |= IFF_PROMISC;
5062 dev->promiscuity += inc;
5063 if (dev->promiscuity == 0) {
5066 * If inc causes overflow, untouch promisc and return error.
5069 dev->flags &= ~IFF_PROMISC;
5071 dev->promiscuity -= inc;
5072 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5077 if (dev->flags != old_flags) {
5078 pr_info("device %s %s promiscuous mode\n",
5080 dev->flags & IFF_PROMISC ? "entered" : "left");
5081 if (audit_enabled) {
5082 current_uid_gid(&uid, &gid);
5083 audit_log(current->audit_context, GFP_ATOMIC,
5084 AUDIT_ANOM_PROMISCUOUS,
5085 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5086 dev->name, (dev->flags & IFF_PROMISC),
5087 (old_flags & IFF_PROMISC),
5088 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5089 from_kuid(&init_user_ns, uid),
5090 from_kgid(&init_user_ns, gid),
5091 audit_get_sessionid(current));
5094 dev_change_rx_flags(dev, IFF_PROMISC);
5097 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5102 * dev_set_promiscuity - update promiscuity count on a device
5106 * Add or remove promiscuity from a device. While the count in the device
5107 * remains above zero the interface remains promiscuous. Once it hits zero
5108 * the device reverts back to normal filtering operation. A negative inc
5109 * value is used to drop promiscuity on the device.
5110 * Return 0 if successful or a negative errno code on error.
5112 int dev_set_promiscuity(struct net_device *dev, int inc)
5114 unsigned int old_flags = dev->flags;
5117 err = __dev_set_promiscuity(dev, inc, true);
5120 if (dev->flags != old_flags)
5121 dev_set_rx_mode(dev);
5124 EXPORT_SYMBOL(dev_set_promiscuity);
5126 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5128 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5132 dev->flags |= IFF_ALLMULTI;
5133 dev->allmulti += inc;
5134 if (dev->allmulti == 0) {
5137 * If inc causes overflow, untouch allmulti and return error.
5140 dev->flags &= ~IFF_ALLMULTI;
5142 dev->allmulti -= inc;
5143 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5148 if (dev->flags ^ old_flags) {
5149 dev_change_rx_flags(dev, IFF_ALLMULTI);
5150 dev_set_rx_mode(dev);
5152 __dev_notify_flags(dev, old_flags,
5153 dev->gflags ^ old_gflags);
5159 * dev_set_allmulti - update allmulti count on a device
5163 * Add or remove reception of all multicast frames to a device. While the
5164 * count in the device remains above zero the interface remains listening
5165 * to all interfaces. Once it hits zero the device reverts back to normal
5166 * filtering operation. A negative @inc value is used to drop the counter
5167 * when releasing a resource needing all multicasts.
5168 * Return 0 if successful or a negative errno code on error.
5171 int dev_set_allmulti(struct net_device *dev, int inc)
5173 return __dev_set_allmulti(dev, inc, true);
5175 EXPORT_SYMBOL(dev_set_allmulti);
5178 * Upload unicast and multicast address lists to device and
5179 * configure RX filtering. When the device doesn't support unicast
5180 * filtering it is put in promiscuous mode while unicast addresses
5183 void __dev_set_rx_mode(struct net_device *dev)
5185 const struct net_device_ops *ops = dev->netdev_ops;
5187 /* dev_open will call this function so the list will stay sane. */
5188 if (!(dev->flags&IFF_UP))
5191 if (!netif_device_present(dev))
5194 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5195 /* Unicast addresses changes may only happen under the rtnl,
5196 * therefore calling __dev_set_promiscuity here is safe.
5198 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5199 __dev_set_promiscuity(dev, 1, false);
5200 dev->uc_promisc = true;
5201 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5202 __dev_set_promiscuity(dev, -1, false);
5203 dev->uc_promisc = false;
5207 if (ops->ndo_set_rx_mode)
5208 ops->ndo_set_rx_mode(dev);
5211 void dev_set_rx_mode(struct net_device *dev)
5213 netif_addr_lock_bh(dev);
5214 __dev_set_rx_mode(dev);
5215 netif_addr_unlock_bh(dev);
5219 * dev_get_flags - get flags reported to userspace
5222 * Get the combination of flag bits exported through APIs to userspace.
5224 unsigned int dev_get_flags(const struct net_device *dev)
5228 flags = (dev->flags & ~(IFF_PROMISC |
5233 (dev->gflags & (IFF_PROMISC |
5236 if (netif_running(dev)) {
5237 if (netif_oper_up(dev))
5238 flags |= IFF_RUNNING;
5239 if (netif_carrier_ok(dev))
5240 flags |= IFF_LOWER_UP;
5241 if (netif_dormant(dev))
5242 flags |= IFF_DORMANT;
5247 EXPORT_SYMBOL(dev_get_flags);
5249 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5251 unsigned int old_flags = dev->flags;
5257 * Set the flags on our device.
5260 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5261 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5263 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5267 * Load in the correct multicast list now the flags have changed.
5270 if ((old_flags ^ flags) & IFF_MULTICAST)
5271 dev_change_rx_flags(dev, IFF_MULTICAST);
5273 dev_set_rx_mode(dev);
5276 * Have we downed the interface. We handle IFF_UP ourselves
5277 * according to user attempts to set it, rather than blindly
5282 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5283 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5286 dev_set_rx_mode(dev);
5289 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5290 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5291 unsigned int old_flags = dev->flags;
5293 dev->gflags ^= IFF_PROMISC;
5295 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5296 if (dev->flags != old_flags)
5297 dev_set_rx_mode(dev);
5300 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5301 is important. Some (broken) drivers set IFF_PROMISC, when
5302 IFF_ALLMULTI is requested not asking us and not reporting.
5304 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5305 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5307 dev->gflags ^= IFF_ALLMULTI;
5308 __dev_set_allmulti(dev, inc, false);
5314 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5315 unsigned int gchanges)
5317 unsigned int changes = dev->flags ^ old_flags;
5320 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5322 if (changes & IFF_UP) {
5323 if (dev->flags & IFF_UP)
5324 call_netdevice_notifiers(NETDEV_UP, dev);
5326 call_netdevice_notifiers(NETDEV_DOWN, dev);
5329 if (dev->flags & IFF_UP &&
5330 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5331 struct netdev_notifier_change_info change_info;
5333 change_info.flags_changed = changes;
5334 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5340 * dev_change_flags - change device settings
5342 * @flags: device state flags
5344 * Change settings on device based state flags. The flags are
5345 * in the userspace exported format.
5347 int dev_change_flags(struct net_device *dev, unsigned int flags)
5350 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5352 ret = __dev_change_flags(dev, flags);
5356 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5357 __dev_notify_flags(dev, old_flags, changes);
5360 EXPORT_SYMBOL(dev_change_flags);
5362 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5364 const struct net_device_ops *ops = dev->netdev_ops;
5366 if (ops->ndo_change_mtu)
5367 return ops->ndo_change_mtu(dev, new_mtu);
5374 * dev_set_mtu - Change maximum transfer unit
5376 * @new_mtu: new transfer unit
5378 * Change the maximum transfer size of the network device.
5380 int dev_set_mtu(struct net_device *dev, int new_mtu)
5384 if (new_mtu == dev->mtu)
5387 /* MTU must be positive. */
5391 if (!netif_device_present(dev))
5394 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
5395 err = notifier_to_errno(err);
5399 orig_mtu = dev->mtu;
5400 err = __dev_set_mtu(dev, new_mtu);
5403 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5404 err = notifier_to_errno(err);
5406 /* setting mtu back and notifying everyone again,
5407 * so that they have a chance to revert changes.
5409 __dev_set_mtu(dev, orig_mtu);
5410 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5415 EXPORT_SYMBOL(dev_set_mtu);
5418 * dev_set_group - Change group this device belongs to
5420 * @new_group: group this device should belong to
5422 void dev_set_group(struct net_device *dev, int new_group)
5424 dev->group = new_group;
5426 EXPORT_SYMBOL(dev_set_group);
5429 * dev_set_mac_address - Change Media Access Control Address
5433 * Change the hardware (MAC) address of the device
5435 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5437 const struct net_device_ops *ops = dev->netdev_ops;
5440 if (!ops->ndo_set_mac_address)
5442 if (sa->sa_family != dev->type)
5444 if (!netif_device_present(dev))
5446 err = ops->ndo_set_mac_address(dev, sa);
5449 dev->addr_assign_type = NET_ADDR_SET;
5450 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5451 add_device_randomness(dev->dev_addr, dev->addr_len);
5454 EXPORT_SYMBOL(dev_set_mac_address);
5457 * dev_change_carrier - Change device carrier
5459 * @new_carrier: new value
5461 * Change device carrier
5463 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5465 const struct net_device_ops *ops = dev->netdev_ops;
5467 if (!ops->ndo_change_carrier)
5469 if (!netif_device_present(dev))
5471 return ops->ndo_change_carrier(dev, new_carrier);
5473 EXPORT_SYMBOL(dev_change_carrier);
5476 * dev_get_phys_port_id - Get device physical port ID
5480 * Get device physical port ID
5482 int dev_get_phys_port_id(struct net_device *dev,
5483 struct netdev_phys_port_id *ppid)
5485 const struct net_device_ops *ops = dev->netdev_ops;
5487 if (!ops->ndo_get_phys_port_id)
5489 return ops->ndo_get_phys_port_id(dev, ppid);
5491 EXPORT_SYMBOL(dev_get_phys_port_id);
5494 * dev_new_index - allocate an ifindex
5495 * @net: the applicable net namespace
5497 * Returns a suitable unique value for a new device interface
5498 * number. The caller must hold the rtnl semaphore or the
5499 * dev_base_lock to be sure it remains unique.
5501 static int dev_new_index(struct net *net)
5503 int ifindex = net->ifindex;
5507 if (!__dev_get_by_index(net, ifindex))
5508 return net->ifindex = ifindex;
5512 /* Delayed registration/unregisteration */
5513 static LIST_HEAD(net_todo_list);
5514 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5516 static void net_set_todo(struct net_device *dev)
5518 list_add_tail(&dev->todo_list, &net_todo_list);
5519 dev_net(dev)->dev_unreg_count++;
5522 static void rollback_registered_many(struct list_head *head)
5524 struct net_device *dev, *tmp;
5525 LIST_HEAD(close_head);
5527 BUG_ON(dev_boot_phase);
5530 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5531 /* Some devices call without registering
5532 * for initialization unwind. Remove those
5533 * devices and proceed with the remaining.
5535 if (dev->reg_state == NETREG_UNINITIALIZED) {
5536 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5540 list_del(&dev->unreg_list);
5543 dev->dismantle = true;
5544 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5547 /* If device is running, close it first. */
5548 list_for_each_entry(dev, head, unreg_list)
5549 list_add_tail(&dev->close_list, &close_head);
5550 dev_close_many(&close_head);
5552 list_for_each_entry(dev, head, unreg_list) {
5553 /* And unlink it from device chain. */
5554 unlist_netdevice(dev);
5556 dev->reg_state = NETREG_UNREGISTERING;
5561 list_for_each_entry(dev, head, unreg_list) {
5562 /* Shutdown queueing discipline. */
5566 /* Notify protocols, that we are about to destroy
5567 this device. They should clean all the things.
5569 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5571 if (!dev->rtnl_link_ops ||
5572 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5573 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5576 * Flush the unicast and multicast chains
5581 if (dev->netdev_ops->ndo_uninit)
5582 dev->netdev_ops->ndo_uninit(dev);
5584 /* Notifier chain MUST detach us all upper devices. */
5585 WARN_ON(netdev_has_any_upper_dev(dev));
5587 /* Remove entries from kobject tree */
5588 netdev_unregister_kobject(dev);
5590 /* Remove XPS queueing entries */
5591 netif_reset_xps_queues_gt(dev, 0);
5597 list_for_each_entry(dev, head, unreg_list)
5601 static void rollback_registered(struct net_device *dev)
5605 list_add(&dev->unreg_list, &single);
5606 rollback_registered_many(&single);
5610 static netdev_features_t netdev_fix_features(struct net_device *dev,
5611 netdev_features_t features)
5613 /* Fix illegal checksum combinations */
5614 if ((features & NETIF_F_HW_CSUM) &&
5615 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5616 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5617 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5620 /* TSO requires that SG is present as well. */
5621 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5622 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5623 features &= ~NETIF_F_ALL_TSO;
5626 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5627 !(features & NETIF_F_IP_CSUM)) {
5628 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5629 features &= ~NETIF_F_TSO;
5630 features &= ~NETIF_F_TSO_ECN;
5633 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5634 !(features & NETIF_F_IPV6_CSUM)) {
5635 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5636 features &= ~NETIF_F_TSO6;
5639 /* TSO ECN requires that TSO is present as well. */
5640 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5641 features &= ~NETIF_F_TSO_ECN;
5643 /* Software GSO depends on SG. */
5644 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5645 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5646 features &= ~NETIF_F_GSO;
5649 /* UFO needs SG and checksumming */
5650 if (features & NETIF_F_UFO) {
5651 /* maybe split UFO into V4 and V6? */
5652 if (!((features & NETIF_F_GEN_CSUM) ||
5653 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5654 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5656 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5657 features &= ~NETIF_F_UFO;
5660 if (!(features & NETIF_F_SG)) {
5662 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5663 features &= ~NETIF_F_UFO;
5670 int __netdev_update_features(struct net_device *dev)
5672 netdev_features_t features;
5677 features = netdev_get_wanted_features(dev);
5679 if (dev->netdev_ops->ndo_fix_features)
5680 features = dev->netdev_ops->ndo_fix_features(dev, features);
5682 /* driver might be less strict about feature dependencies */
5683 features = netdev_fix_features(dev, features);
5685 if (dev->features == features)
5688 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5689 &dev->features, &features);
5691 if (dev->netdev_ops->ndo_set_features)
5692 err = dev->netdev_ops->ndo_set_features(dev, features);
5694 if (unlikely(err < 0)) {
5696 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5697 err, &features, &dev->features);
5702 dev->features = features;
5708 * netdev_update_features - recalculate device features
5709 * @dev: the device to check
5711 * Recalculate dev->features set and send notifications if it
5712 * has changed. Should be called after driver or hardware dependent
5713 * conditions might have changed that influence the features.
5715 void netdev_update_features(struct net_device *dev)
5717 if (__netdev_update_features(dev))
5718 netdev_features_change(dev);
5720 EXPORT_SYMBOL(netdev_update_features);
5723 * netdev_change_features - recalculate device features
5724 * @dev: the device to check
5726 * Recalculate dev->features set and send notifications even
5727 * if they have not changed. Should be called instead of
5728 * netdev_update_features() if also dev->vlan_features might
5729 * have changed to allow the changes to be propagated to stacked
5732 void netdev_change_features(struct net_device *dev)
5734 __netdev_update_features(dev);
5735 netdev_features_change(dev);
5737 EXPORT_SYMBOL(netdev_change_features);
5740 * netif_stacked_transfer_operstate - transfer operstate
5741 * @rootdev: the root or lower level device to transfer state from
5742 * @dev: the device to transfer operstate to
5744 * Transfer operational state from root to device. This is normally
5745 * called when a stacking relationship exists between the root
5746 * device and the device(a leaf device).
5748 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5749 struct net_device *dev)
5751 if (rootdev->operstate == IF_OPER_DORMANT)
5752 netif_dormant_on(dev);
5754 netif_dormant_off(dev);
5756 if (netif_carrier_ok(rootdev)) {
5757 if (!netif_carrier_ok(dev))
5758 netif_carrier_on(dev);
5760 if (netif_carrier_ok(dev))
5761 netif_carrier_off(dev);
5764 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5767 static int netif_alloc_rx_queues(struct net_device *dev)
5769 unsigned int i, count = dev->num_rx_queues;
5770 struct netdev_rx_queue *rx;
5774 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5780 for (i = 0; i < count; i++)
5786 static void netdev_init_one_queue(struct net_device *dev,
5787 struct netdev_queue *queue, void *_unused)
5789 /* Initialize queue lock */
5790 spin_lock_init(&queue->_xmit_lock);
5791 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5792 queue->xmit_lock_owner = -1;
5793 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5796 dql_init(&queue->dql, HZ);
5800 static void netif_free_tx_queues(struct net_device *dev)
5802 if (is_vmalloc_addr(dev->_tx))
5808 static int netif_alloc_netdev_queues(struct net_device *dev)
5810 unsigned int count = dev->num_tx_queues;
5811 struct netdev_queue *tx;
5812 size_t sz = count * sizeof(*tx);
5814 BUG_ON(count < 1 || count > 0xffff);
5816 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5824 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5825 spin_lock_init(&dev->tx_global_lock);
5831 * register_netdevice - register a network device
5832 * @dev: device to register
5834 * Take a completed network device structure and add it to the kernel
5835 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5836 * chain. 0 is returned on success. A negative errno code is returned
5837 * on a failure to set up the device, or if the name is a duplicate.
5839 * Callers must hold the rtnl semaphore. You may want
5840 * register_netdev() instead of this.
5843 * The locking appears insufficient to guarantee two parallel registers
5844 * will not get the same name.
5847 int register_netdevice(struct net_device *dev)
5850 struct net *net = dev_net(dev);
5852 BUG_ON(dev_boot_phase);
5857 /* When net_device's are persistent, this will be fatal. */
5858 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5861 spin_lock_init(&dev->addr_list_lock);
5862 netdev_set_addr_lockdep_class(dev);
5866 ret = dev_get_valid_name(net, dev, dev->name);
5870 /* Init, if this function is available */
5871 if (dev->netdev_ops->ndo_init) {
5872 ret = dev->netdev_ops->ndo_init(dev);
5880 if (((dev->hw_features | dev->features) &
5881 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5882 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5883 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5884 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5891 dev->ifindex = dev_new_index(net);
5892 else if (__dev_get_by_index(net, dev->ifindex))
5895 if (dev->iflink == -1)
5896 dev->iflink = dev->ifindex;
5898 /* Transfer changeable features to wanted_features and enable
5899 * software offloads (GSO and GRO).
5901 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5902 dev->features |= NETIF_F_SOFT_FEATURES;
5903 dev->wanted_features = dev->features & dev->hw_features;
5905 if (!(dev->flags & IFF_LOOPBACK)) {
5906 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5909 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5911 dev->vlan_features |= NETIF_F_HIGHDMA;
5913 /* Make NETIF_F_SG inheritable to tunnel devices.
5915 dev->hw_enc_features |= NETIF_F_SG;
5917 /* Make NETIF_F_SG inheritable to MPLS.
5919 dev->mpls_features |= NETIF_F_SG;
5921 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5922 ret = notifier_to_errno(ret);
5926 ret = netdev_register_kobject(dev);
5929 dev->reg_state = NETREG_REGISTERED;
5931 __netdev_update_features(dev);
5934 * Default initial state at registry is that the
5935 * device is present.
5938 set_bit(__LINK_STATE_PRESENT, &dev->state);
5940 linkwatch_init_dev(dev);
5942 dev_init_scheduler(dev);
5944 list_netdevice(dev);
5945 add_device_randomness(dev->dev_addr, dev->addr_len);
5947 /* If the device has permanent device address, driver should
5948 * set dev_addr and also addr_assign_type should be set to
5949 * NET_ADDR_PERM (default value).
5951 if (dev->addr_assign_type == NET_ADDR_PERM)
5952 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5954 /* Notify protocols, that a new device appeared. */
5955 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5956 ret = notifier_to_errno(ret);
5958 rollback_registered(dev);
5959 dev->reg_state = NETREG_UNREGISTERED;
5962 * Prevent userspace races by waiting until the network
5963 * device is fully setup before sending notifications.
5965 if (!dev->rtnl_link_ops ||
5966 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5967 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5973 if (dev->netdev_ops->ndo_uninit)
5974 dev->netdev_ops->ndo_uninit(dev);
5977 EXPORT_SYMBOL(register_netdevice);
5980 * init_dummy_netdev - init a dummy network device for NAPI
5981 * @dev: device to init
5983 * This takes a network device structure and initialize the minimum
5984 * amount of fields so it can be used to schedule NAPI polls without
5985 * registering a full blown interface. This is to be used by drivers
5986 * that need to tie several hardware interfaces to a single NAPI
5987 * poll scheduler due to HW limitations.
5989 int init_dummy_netdev(struct net_device *dev)
5991 /* Clear everything. Note we don't initialize spinlocks
5992 * are they aren't supposed to be taken by any of the
5993 * NAPI code and this dummy netdev is supposed to be
5994 * only ever used for NAPI polls
5996 memset(dev, 0, sizeof(struct net_device));
5998 /* make sure we BUG if trying to hit standard
5999 * register/unregister code path
6001 dev->reg_state = NETREG_DUMMY;
6003 /* NAPI wants this */
6004 INIT_LIST_HEAD(&dev->napi_list);
6006 /* a dummy interface is started by default */
6007 set_bit(__LINK_STATE_PRESENT, &dev->state);
6008 set_bit(__LINK_STATE_START, &dev->state);
6010 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6011 * because users of this 'device' dont need to change
6017 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6021 * register_netdev - register a network device
6022 * @dev: device to register
6024 * Take a completed network device structure and add it to the kernel
6025 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6026 * chain. 0 is returned on success. A negative errno code is returned
6027 * on a failure to set up the device, or if the name is a duplicate.
6029 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6030 * and expands the device name if you passed a format string to
6033 int register_netdev(struct net_device *dev)
6038 err = register_netdevice(dev);
6042 EXPORT_SYMBOL(register_netdev);
6044 int netdev_refcnt_read(const struct net_device *dev)
6048 for_each_possible_cpu(i)
6049 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6052 EXPORT_SYMBOL(netdev_refcnt_read);
6055 * netdev_wait_allrefs - wait until all references are gone.
6056 * @dev: target net_device
6058 * This is called when unregistering network devices.
6060 * Any protocol or device that holds a reference should register
6061 * for netdevice notification, and cleanup and put back the
6062 * reference if they receive an UNREGISTER event.
6063 * We can get stuck here if buggy protocols don't correctly
6066 static void netdev_wait_allrefs(struct net_device *dev)
6068 unsigned long rebroadcast_time, warning_time;
6071 linkwatch_forget_dev(dev);
6073 rebroadcast_time = warning_time = jiffies;
6074 refcnt = netdev_refcnt_read(dev);
6076 while (refcnt != 0) {
6077 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6080 /* Rebroadcast unregister notification */
6081 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6087 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6088 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6090 /* We must not have linkwatch events
6091 * pending on unregister. If this
6092 * happens, we simply run the queue
6093 * unscheduled, resulting in a noop
6096 linkwatch_run_queue();
6101 rebroadcast_time = jiffies;
6106 refcnt = netdev_refcnt_read(dev);
6108 if (time_after(jiffies, warning_time + 10 * HZ)) {
6109 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6111 warning_time = jiffies;
6120 * register_netdevice(x1);
6121 * register_netdevice(x2);
6123 * unregister_netdevice(y1);
6124 * unregister_netdevice(y2);
6130 * We are invoked by rtnl_unlock().
6131 * This allows us to deal with problems:
6132 * 1) We can delete sysfs objects which invoke hotplug
6133 * without deadlocking with linkwatch via keventd.
6134 * 2) Since we run with the RTNL semaphore not held, we can sleep
6135 * safely in order to wait for the netdev refcnt to drop to zero.
6137 * We must not return until all unregister events added during
6138 * the interval the lock was held have been completed.
6140 void netdev_run_todo(void)
6142 struct list_head list;
6144 /* Snapshot list, allow later requests */
6145 list_replace_init(&net_todo_list, &list);
6150 /* Wait for rcu callbacks to finish before next phase */
6151 if (!list_empty(&list))
6154 while (!list_empty(&list)) {
6155 struct net_device *dev
6156 = list_first_entry(&list, struct net_device, todo_list);
6157 list_del(&dev->todo_list);
6160 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6163 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6164 pr_err("network todo '%s' but state %d\n",
6165 dev->name, dev->reg_state);
6170 dev->reg_state = NETREG_UNREGISTERED;
6172 on_each_cpu(flush_backlog, dev, 1);
6174 netdev_wait_allrefs(dev);
6177 BUG_ON(netdev_refcnt_read(dev));
6178 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6179 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6180 WARN_ON(dev->dn_ptr);
6182 if (dev->destructor)
6183 dev->destructor(dev);
6185 /* Report a network device has been unregistered */
6187 dev_net(dev)->dev_unreg_count--;
6189 wake_up(&netdev_unregistering_wq);
6191 /* Free network device */
6192 kobject_put(&dev->dev.kobj);
6196 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6197 * fields in the same order, with only the type differing.
6199 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6200 const struct net_device_stats *netdev_stats)
6202 #if BITS_PER_LONG == 64
6203 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6204 memcpy(stats64, netdev_stats, sizeof(*stats64));
6206 size_t i, n = sizeof(*stats64) / sizeof(u64);
6207 const unsigned long *src = (const unsigned long *)netdev_stats;
6208 u64 *dst = (u64 *)stats64;
6210 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6211 sizeof(*stats64) / sizeof(u64));
6212 for (i = 0; i < n; i++)
6216 EXPORT_SYMBOL(netdev_stats_to_stats64);
6219 * dev_get_stats - get network device statistics
6220 * @dev: device to get statistics from
6221 * @storage: place to store stats
6223 * Get network statistics from device. Return @storage.
6224 * The device driver may provide its own method by setting
6225 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6226 * otherwise the internal statistics structure is used.
6228 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6229 struct rtnl_link_stats64 *storage)
6231 const struct net_device_ops *ops = dev->netdev_ops;
6233 if (ops->ndo_get_stats64) {
6234 memset(storage, 0, sizeof(*storage));
6235 ops->ndo_get_stats64(dev, storage);
6236 } else if (ops->ndo_get_stats) {
6237 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6239 netdev_stats_to_stats64(storage, &dev->stats);
6241 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6242 storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6245 EXPORT_SYMBOL(dev_get_stats);
6247 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6249 struct netdev_queue *queue = dev_ingress_queue(dev);
6251 #ifdef CONFIG_NET_CLS_ACT
6254 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6257 netdev_init_one_queue(dev, queue, NULL);
6258 queue->qdisc = &noop_qdisc;
6259 queue->qdisc_sleeping = &noop_qdisc;
6260 rcu_assign_pointer(dev->ingress_queue, queue);
6265 static const struct ethtool_ops default_ethtool_ops;
6267 void netdev_set_default_ethtool_ops(struct net_device *dev,
6268 const struct ethtool_ops *ops)
6270 if (dev->ethtool_ops == &default_ethtool_ops)
6271 dev->ethtool_ops = ops;
6273 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6275 void netdev_freemem(struct net_device *dev)
6277 char *addr = (char *)dev - dev->padded;
6279 if (is_vmalloc_addr(addr))
6286 * alloc_netdev_mqs - allocate network device
6287 * @sizeof_priv: size of private data to allocate space for
6288 * @name: device name format string
6289 * @setup: callback to initialize device
6290 * @txqs: the number of TX subqueues to allocate
6291 * @rxqs: the number of RX subqueues to allocate
6293 * Allocates a struct net_device with private data area for driver use
6294 * and performs basic initialization. Also allocates subqueue structs
6295 * for each queue on the device.
6297 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6298 void (*setup)(struct net_device *),
6299 unsigned int txqs, unsigned int rxqs)
6301 struct net_device *dev;
6303 struct net_device *p;
6305 BUG_ON(strlen(name) >= sizeof(dev->name));
6308 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6314 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6319 alloc_size = sizeof(struct net_device);
6321 /* ensure 32-byte alignment of private area */
6322 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6323 alloc_size += sizeof_priv;
6325 /* ensure 32-byte alignment of whole construct */
6326 alloc_size += NETDEV_ALIGN - 1;
6328 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6330 p = vzalloc(alloc_size);
6334 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6335 dev->padded = (char *)dev - (char *)p;
6337 dev->pcpu_refcnt = alloc_percpu(int);
6338 if (!dev->pcpu_refcnt)
6341 if (dev_addr_init(dev))
6347 dev_net_set(dev, &init_net);
6349 dev->gso_max_size = GSO_MAX_SIZE;
6350 dev->gso_max_segs = GSO_MAX_SEGS;
6352 INIT_LIST_HEAD(&dev->napi_list);
6353 INIT_LIST_HEAD(&dev->unreg_list);
6354 INIT_LIST_HEAD(&dev->close_list);
6355 INIT_LIST_HEAD(&dev->link_watch_list);
6356 INIT_LIST_HEAD(&dev->adj_list.upper);
6357 INIT_LIST_HEAD(&dev->adj_list.lower);
6358 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6359 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6360 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6363 dev->num_tx_queues = txqs;
6364 dev->real_num_tx_queues = txqs;
6365 if (netif_alloc_netdev_queues(dev))
6369 dev->num_rx_queues = rxqs;
6370 dev->real_num_rx_queues = rxqs;
6371 if (netif_alloc_rx_queues(dev))
6375 strcpy(dev->name, name);
6376 dev->group = INIT_NETDEV_GROUP;
6377 if (!dev->ethtool_ops)
6378 dev->ethtool_ops = &default_ethtool_ops;
6386 free_percpu(dev->pcpu_refcnt);
6387 netif_free_tx_queues(dev);
6393 netdev_freemem(dev);
6396 EXPORT_SYMBOL(alloc_netdev_mqs);
6399 * free_netdev - free network device
6402 * This function does the last stage of destroying an allocated device
6403 * interface. The reference to the device object is released.
6404 * If this is the last reference then it will be freed.
6406 void free_netdev(struct net_device *dev)
6408 struct napi_struct *p, *n;
6410 release_net(dev_net(dev));
6412 netif_free_tx_queues(dev);
6417 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6419 /* Flush device addresses */
6420 dev_addr_flush(dev);
6422 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6425 free_percpu(dev->pcpu_refcnt);
6426 dev->pcpu_refcnt = NULL;
6428 /* Compatibility with error handling in drivers */
6429 if (dev->reg_state == NETREG_UNINITIALIZED) {
6430 netdev_freemem(dev);
6434 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6435 dev->reg_state = NETREG_RELEASED;
6437 /* will free via device release */
6438 put_device(&dev->dev);
6440 EXPORT_SYMBOL(free_netdev);
6443 * synchronize_net - Synchronize with packet receive processing
6445 * Wait for packets currently being received to be done.
6446 * Does not block later packets from starting.
6448 void synchronize_net(void)
6451 if (rtnl_is_locked())
6452 synchronize_rcu_expedited();
6456 EXPORT_SYMBOL(synchronize_net);
6459 * unregister_netdevice_queue - remove device from the kernel
6463 * This function shuts down a device interface and removes it
6464 * from the kernel tables.
6465 * If head not NULL, device is queued to be unregistered later.
6467 * Callers must hold the rtnl semaphore. You may want
6468 * unregister_netdev() instead of this.
6471 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6476 list_move_tail(&dev->unreg_list, head);
6478 rollback_registered(dev);
6479 /* Finish processing unregister after unlock */
6483 EXPORT_SYMBOL(unregister_netdevice_queue);
6486 * unregister_netdevice_many - unregister many devices
6487 * @head: list of devices
6489 void unregister_netdevice_many(struct list_head *head)
6491 struct net_device *dev;
6493 if (!list_empty(head)) {
6494 rollback_registered_many(head);
6495 list_for_each_entry(dev, head, unreg_list)
6499 EXPORT_SYMBOL(unregister_netdevice_many);
6502 * unregister_netdev - remove device from the kernel
6505 * This function shuts down a device interface and removes it
6506 * from the kernel tables.
6508 * This is just a wrapper for unregister_netdevice that takes
6509 * the rtnl semaphore. In general you want to use this and not
6510 * unregister_netdevice.
6512 void unregister_netdev(struct net_device *dev)
6515 unregister_netdevice(dev);
6518 EXPORT_SYMBOL(unregister_netdev);
6521 * dev_change_net_namespace - move device to different nethost namespace
6523 * @net: network namespace
6524 * @pat: If not NULL name pattern to try if the current device name
6525 * is already taken in the destination network namespace.
6527 * This function shuts down a device interface and moves it
6528 * to a new network namespace. On success 0 is returned, on
6529 * a failure a netagive errno code is returned.
6531 * Callers must hold the rtnl semaphore.
6534 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6540 /* Don't allow namespace local devices to be moved. */
6542 if (dev->features & NETIF_F_NETNS_LOCAL)
6545 /* Ensure the device has been registrered */
6546 if (dev->reg_state != NETREG_REGISTERED)
6549 /* Get out if there is nothing todo */
6551 if (net_eq(dev_net(dev), net))
6554 /* Pick the destination device name, and ensure
6555 * we can use it in the destination network namespace.
6558 if (__dev_get_by_name(net, dev->name)) {
6559 /* We get here if we can't use the current device name */
6562 if (dev_get_valid_name(net, dev, pat) < 0)
6567 * And now a mini version of register_netdevice unregister_netdevice.
6570 /* If device is running close it first. */
6573 /* And unlink it from device chain */
6575 unlist_netdevice(dev);
6579 /* Shutdown queueing discipline. */
6582 /* Notify protocols, that we are about to destroy
6583 this device. They should clean all the things.
6585 Note that dev->reg_state stays at NETREG_REGISTERED.
6586 This is wanted because this way 8021q and macvlan know
6587 the device is just moving and can keep their slaves up.
6589 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6591 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6592 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6595 * Flush the unicast and multicast chains
6600 /* Send a netdev-removed uevent to the old namespace */
6601 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6603 /* Actually switch the network namespace */
6604 dev_net_set(dev, net);
6606 /* If there is an ifindex conflict assign a new one */
6607 if (__dev_get_by_index(net, dev->ifindex)) {
6608 int iflink = (dev->iflink == dev->ifindex);
6609 dev->ifindex = dev_new_index(net);
6611 dev->iflink = dev->ifindex;
6614 /* Send a netdev-add uevent to the new namespace */
6615 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6617 /* Fixup kobjects */
6618 err = device_rename(&dev->dev, dev->name);
6621 /* Add the device back in the hashes */
6622 list_netdevice(dev);
6624 /* Notify protocols, that a new device appeared. */
6625 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6628 * Prevent userspace races by waiting until the network
6629 * device is fully setup before sending notifications.
6631 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6638 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6640 static int dev_cpu_callback(struct notifier_block *nfb,
6641 unsigned long action,
6644 struct sk_buff **list_skb;
6645 struct sk_buff *skb;
6646 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6647 struct softnet_data *sd, *oldsd;
6649 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6652 local_irq_disable();
6653 cpu = smp_processor_id();
6654 sd = &per_cpu(softnet_data, cpu);
6655 oldsd = &per_cpu(softnet_data, oldcpu);
6657 /* Find end of our completion_queue. */
6658 list_skb = &sd->completion_queue;
6660 list_skb = &(*list_skb)->next;
6661 /* Append completion queue from offline CPU. */
6662 *list_skb = oldsd->completion_queue;
6663 oldsd->completion_queue = NULL;
6665 /* Append output queue from offline CPU. */
6666 if (oldsd->output_queue) {
6667 *sd->output_queue_tailp = oldsd->output_queue;
6668 sd->output_queue_tailp = oldsd->output_queue_tailp;
6669 oldsd->output_queue = NULL;
6670 oldsd->output_queue_tailp = &oldsd->output_queue;
6672 /* Append NAPI poll list from offline CPU. */
6673 if (!list_empty(&oldsd->poll_list)) {
6674 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6675 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6678 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6681 /* Process offline CPU's input_pkt_queue */
6682 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6683 netif_rx_internal(skb);
6684 input_queue_head_incr(oldsd);
6686 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6687 netif_rx_internal(skb);
6688 input_queue_head_incr(oldsd);
6696 * netdev_increment_features - increment feature set by one
6697 * @all: current feature set
6698 * @one: new feature set
6699 * @mask: mask feature set
6701 * Computes a new feature set after adding a device with feature set
6702 * @one to the master device with current feature set @all. Will not
6703 * enable anything that is off in @mask. Returns the new feature set.
6705 netdev_features_t netdev_increment_features(netdev_features_t all,
6706 netdev_features_t one, netdev_features_t mask)
6708 if (mask & NETIF_F_GEN_CSUM)
6709 mask |= NETIF_F_ALL_CSUM;
6710 mask |= NETIF_F_VLAN_CHALLENGED;
6712 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6713 all &= one | ~NETIF_F_ALL_FOR_ALL;
6715 /* If one device supports hw checksumming, set for all. */
6716 if (all & NETIF_F_GEN_CSUM)
6717 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6721 EXPORT_SYMBOL(netdev_increment_features);
6723 static struct hlist_head * __net_init netdev_create_hash(void)
6726 struct hlist_head *hash;
6728 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6730 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6731 INIT_HLIST_HEAD(&hash[i]);
6736 /* Initialize per network namespace state */
6737 static int __net_init netdev_init(struct net *net)
6739 if (net != &init_net)
6740 INIT_LIST_HEAD(&net->dev_base_head);
6742 net->dev_name_head = netdev_create_hash();
6743 if (net->dev_name_head == NULL)
6746 net->dev_index_head = netdev_create_hash();
6747 if (net->dev_index_head == NULL)
6753 kfree(net->dev_name_head);
6759 * netdev_drivername - network driver for the device
6760 * @dev: network device
6762 * Determine network driver for device.
6764 const char *netdev_drivername(const struct net_device *dev)
6766 const struct device_driver *driver;
6767 const struct device *parent;
6768 const char *empty = "";
6770 parent = dev->dev.parent;
6774 driver = parent->driver;
6775 if (driver && driver->name)
6776 return driver->name;
6780 static int __netdev_printk(const char *level, const struct net_device *dev,
6781 struct va_format *vaf)
6785 if (dev && dev->dev.parent) {
6786 r = dev_printk_emit(level[1] - '0',
6789 dev_driver_string(dev->dev.parent),
6790 dev_name(dev->dev.parent),
6791 netdev_name(dev), vaf);
6793 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6795 r = printk("%s(NULL net_device): %pV", level, vaf);
6801 int netdev_printk(const char *level, const struct net_device *dev,
6802 const char *format, ...)
6804 struct va_format vaf;
6808 va_start(args, format);
6813 r = __netdev_printk(level, dev, &vaf);
6819 EXPORT_SYMBOL(netdev_printk);
6821 #define define_netdev_printk_level(func, level) \
6822 int func(const struct net_device *dev, const char *fmt, ...) \
6825 struct va_format vaf; \
6828 va_start(args, fmt); \
6833 r = __netdev_printk(level, dev, &vaf); \
6839 EXPORT_SYMBOL(func);
6841 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6842 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6843 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6844 define_netdev_printk_level(netdev_err, KERN_ERR);
6845 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6846 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6847 define_netdev_printk_level(netdev_info, KERN_INFO);
6849 static void __net_exit netdev_exit(struct net *net)
6851 kfree(net->dev_name_head);
6852 kfree(net->dev_index_head);
6855 static struct pernet_operations __net_initdata netdev_net_ops = {
6856 .init = netdev_init,
6857 .exit = netdev_exit,
6860 static void __net_exit default_device_exit(struct net *net)
6862 struct net_device *dev, *aux;
6864 * Push all migratable network devices back to the
6865 * initial network namespace
6868 for_each_netdev_safe(net, dev, aux) {
6870 char fb_name[IFNAMSIZ];
6872 /* Ignore unmoveable devices (i.e. loopback) */
6873 if (dev->features & NETIF_F_NETNS_LOCAL)
6876 /* Leave virtual devices for the generic cleanup */
6877 if (dev->rtnl_link_ops)
6880 /* Push remaining network devices to init_net */
6881 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6882 err = dev_change_net_namespace(dev, &init_net, fb_name);
6884 pr_emerg("%s: failed to move %s to init_net: %d\n",
6885 __func__, dev->name, err);
6892 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6894 /* Return with the rtnl_lock held when there are no network
6895 * devices unregistering in any network namespace in net_list.
6902 prepare_to_wait(&netdev_unregistering_wq, &wait,
6903 TASK_UNINTERRUPTIBLE);
6904 unregistering = false;
6906 list_for_each_entry(net, net_list, exit_list) {
6907 if (net->dev_unreg_count > 0) {
6908 unregistering = true;
6917 finish_wait(&netdev_unregistering_wq, &wait);
6920 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6922 /* At exit all network devices most be removed from a network
6923 * namespace. Do this in the reverse order of registration.
6924 * Do this across as many network namespaces as possible to
6925 * improve batching efficiency.
6927 struct net_device *dev;
6929 LIST_HEAD(dev_kill_list);
6931 /* To prevent network device cleanup code from dereferencing
6932 * loopback devices or network devices that have been freed
6933 * wait here for all pending unregistrations to complete,
6934 * before unregistring the loopback device and allowing the
6935 * network namespace be freed.
6937 * The netdev todo list containing all network devices
6938 * unregistrations that happen in default_device_exit_batch
6939 * will run in the rtnl_unlock() at the end of
6940 * default_device_exit_batch.
6942 rtnl_lock_unregistering(net_list);
6943 list_for_each_entry(net, net_list, exit_list) {
6944 for_each_netdev_reverse(net, dev) {
6945 if (dev->rtnl_link_ops)
6946 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6948 unregister_netdevice_queue(dev, &dev_kill_list);
6951 unregister_netdevice_many(&dev_kill_list);
6952 list_del(&dev_kill_list);
6956 static struct pernet_operations __net_initdata default_device_ops = {
6957 .exit = default_device_exit,
6958 .exit_batch = default_device_exit_batch,
6962 * Initialize the DEV module. At boot time this walks the device list and
6963 * unhooks any devices that fail to initialise (normally hardware not
6964 * present) and leaves us with a valid list of present and active devices.
6969 * This is called single threaded during boot, so no need
6970 * to take the rtnl semaphore.
6972 static int __init net_dev_init(void)
6974 int i, rc = -ENOMEM;
6976 BUG_ON(!dev_boot_phase);
6978 if (dev_proc_init())
6981 if (netdev_kobject_init())
6984 INIT_LIST_HEAD(&ptype_all);
6985 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6986 INIT_LIST_HEAD(&ptype_base[i]);
6988 INIT_LIST_HEAD(&offload_base);
6990 if (register_pernet_subsys(&netdev_net_ops))
6994 * Initialise the packet receive queues.
6997 for_each_possible_cpu(i) {
6998 struct softnet_data *sd = &per_cpu(softnet_data, i);
7000 skb_queue_head_init(&sd->input_pkt_queue);
7001 skb_queue_head_init(&sd->process_queue);
7002 INIT_LIST_HEAD(&sd->poll_list);
7003 sd->output_queue_tailp = &sd->output_queue;
7005 sd->csd.func = rps_trigger_softirq;
7010 sd->backlog.poll = process_backlog;
7011 sd->backlog.weight = weight_p;
7016 /* The loopback device is special if any other network devices
7017 * is present in a network namespace the loopback device must
7018 * be present. Since we now dynamically allocate and free the
7019 * loopback device ensure this invariant is maintained by
7020 * keeping the loopback device as the first device on the
7021 * list of network devices. Ensuring the loopback devices
7022 * is the first device that appears and the last network device
7025 if (register_pernet_device(&loopback_net_ops))
7028 if (register_pernet_device(&default_device_ops))
7031 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7032 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7034 hotcpu_notifier(dev_cpu_callback, 0);
7041 subsys_initcall(net_dev_init);