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();
2886 rcu_read_unlock_bh();
2890 int dev_queue_xmit(struct sk_buff *skb)
2892 return __dev_queue_xmit(skb, NULL);
2894 EXPORT_SYMBOL(dev_queue_xmit);
2896 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2898 return __dev_queue_xmit(skb, accel_priv);
2900 EXPORT_SYMBOL(dev_queue_xmit_accel);
2903 /*=======================================================================
2905 =======================================================================*/
2907 int netdev_max_backlog __read_mostly = 1000;
2908 EXPORT_SYMBOL(netdev_max_backlog);
2910 int netdev_tstamp_prequeue __read_mostly = 1;
2911 int netdev_budget __read_mostly = 300;
2912 int weight_p __read_mostly = 64; /* old backlog weight */
2914 /* Called with irq disabled */
2915 static inline void ____napi_schedule(struct softnet_data *sd,
2916 struct napi_struct *napi)
2918 list_add_tail(&napi->poll_list, &sd->poll_list);
2919 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2924 /* One global table that all flow-based protocols share. */
2925 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2926 EXPORT_SYMBOL(rps_sock_flow_table);
2928 struct static_key rps_needed __read_mostly;
2930 static struct rps_dev_flow *
2931 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2932 struct rps_dev_flow *rflow, u16 next_cpu)
2934 if (next_cpu != RPS_NO_CPU) {
2935 #ifdef CONFIG_RFS_ACCEL
2936 struct netdev_rx_queue *rxqueue;
2937 struct rps_dev_flow_table *flow_table;
2938 struct rps_dev_flow *old_rflow;
2943 /* Should we steer this flow to a different hardware queue? */
2944 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2945 !(dev->features & NETIF_F_NTUPLE))
2947 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2948 if (rxq_index == skb_get_rx_queue(skb))
2951 rxqueue = dev->_rx + rxq_index;
2952 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2955 flow_id = skb->rxhash & flow_table->mask;
2956 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2957 rxq_index, flow_id);
2961 rflow = &flow_table->flows[flow_id];
2963 if (old_rflow->filter == rflow->filter)
2964 old_rflow->filter = RPS_NO_FILTER;
2968 per_cpu(softnet_data, next_cpu).input_queue_head;
2971 rflow->cpu = next_cpu;
2976 * get_rps_cpu is called from netif_receive_skb and returns the target
2977 * CPU from the RPS map of the receiving queue for a given skb.
2978 * rcu_read_lock must be held on entry.
2980 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2981 struct rps_dev_flow **rflowp)
2983 struct netdev_rx_queue *rxqueue;
2984 struct rps_map *map;
2985 struct rps_dev_flow_table *flow_table;
2986 struct rps_sock_flow_table *sock_flow_table;
2990 if (skb_rx_queue_recorded(skb)) {
2991 u16 index = skb_get_rx_queue(skb);
2992 if (unlikely(index >= dev->real_num_rx_queues)) {
2993 WARN_ONCE(dev->real_num_rx_queues > 1,
2994 "%s received packet on queue %u, but number "
2995 "of RX queues is %u\n",
2996 dev->name, index, dev->real_num_rx_queues);
2999 rxqueue = dev->_rx + index;
3003 map = rcu_dereference(rxqueue->rps_map);
3005 if (map->len == 1 &&
3006 !rcu_access_pointer(rxqueue->rps_flow_table)) {
3007 tcpu = map->cpus[0];
3008 if (cpu_online(tcpu))
3012 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3016 skb_reset_network_header(skb);
3017 if (!skb_get_hash(skb))
3020 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3021 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3022 if (flow_table && sock_flow_table) {
3024 struct rps_dev_flow *rflow;
3026 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3029 next_cpu = sock_flow_table->ents[skb->rxhash &
3030 sock_flow_table->mask];
3033 * If the desired CPU (where last recvmsg was done) is
3034 * different from current CPU (one in the rx-queue flow
3035 * table entry), switch if one of the following holds:
3036 * - Current CPU is unset (equal to RPS_NO_CPU).
3037 * - Current CPU is offline.
3038 * - The current CPU's queue tail has advanced beyond the
3039 * last packet that was enqueued using this table entry.
3040 * This guarantees that all previous packets for the flow
3041 * have been dequeued, thus preserving in order delivery.
3043 if (unlikely(tcpu != next_cpu) &&
3044 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3045 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3046 rflow->last_qtail)) >= 0)) {
3048 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3051 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3059 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3061 if (cpu_online(tcpu)) {
3071 #ifdef CONFIG_RFS_ACCEL
3074 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3075 * @dev: Device on which the filter was set
3076 * @rxq_index: RX queue index
3077 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3078 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3080 * Drivers that implement ndo_rx_flow_steer() should periodically call
3081 * this function for each installed filter and remove the filters for
3082 * which it returns %true.
3084 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3085 u32 flow_id, u16 filter_id)
3087 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3088 struct rps_dev_flow_table *flow_table;
3089 struct rps_dev_flow *rflow;
3094 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3095 if (flow_table && flow_id <= flow_table->mask) {
3096 rflow = &flow_table->flows[flow_id];
3097 cpu = ACCESS_ONCE(rflow->cpu);
3098 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3099 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3100 rflow->last_qtail) <
3101 (int)(10 * flow_table->mask)))
3107 EXPORT_SYMBOL(rps_may_expire_flow);
3109 #endif /* CONFIG_RFS_ACCEL */
3111 /* Called from hardirq (IPI) context */
3112 static void rps_trigger_softirq(void *data)
3114 struct softnet_data *sd = data;
3116 ____napi_schedule(sd, &sd->backlog);
3120 #endif /* CONFIG_RPS */
3123 * Check if this softnet_data structure is another cpu one
3124 * If yes, queue it to our IPI list and return 1
3127 static int rps_ipi_queued(struct softnet_data *sd)
3130 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3133 sd->rps_ipi_next = mysd->rps_ipi_list;
3134 mysd->rps_ipi_list = sd;
3136 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3139 #endif /* CONFIG_RPS */
3143 #ifdef CONFIG_NET_FLOW_LIMIT
3144 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3147 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3149 #ifdef CONFIG_NET_FLOW_LIMIT
3150 struct sd_flow_limit *fl;
3151 struct softnet_data *sd;
3152 unsigned int old_flow, new_flow;
3154 if (qlen < (netdev_max_backlog >> 1))
3157 sd = &__get_cpu_var(softnet_data);
3160 fl = rcu_dereference(sd->flow_limit);
3162 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3163 old_flow = fl->history[fl->history_head];
3164 fl->history[fl->history_head] = new_flow;
3167 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3169 if (likely(fl->buckets[old_flow]))
3170 fl->buckets[old_flow]--;
3172 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3184 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3185 * queue (may be a remote CPU queue).
3187 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3188 unsigned int *qtail)
3190 struct softnet_data *sd;
3191 unsigned long flags;
3194 sd = &per_cpu(softnet_data, cpu);
3196 local_irq_save(flags);
3199 qlen = skb_queue_len(&sd->input_pkt_queue);
3200 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3201 if (skb_queue_len(&sd->input_pkt_queue)) {
3203 __skb_queue_tail(&sd->input_pkt_queue, skb);
3204 input_queue_tail_incr_save(sd, qtail);
3206 local_irq_restore(flags);
3207 return NET_RX_SUCCESS;
3210 /* Schedule NAPI for backlog device
3211 * We can use non atomic operation since we own the queue lock
3213 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3214 if (!rps_ipi_queued(sd))
3215 ____napi_schedule(sd, &sd->backlog);
3223 local_irq_restore(flags);
3225 atomic_long_inc(&skb->dev->rx_dropped);
3230 static int netif_rx_internal(struct sk_buff *skb)
3234 /* if netpoll wants it, pretend we never saw it */
3235 if (netpoll_rx(skb))
3238 net_timestamp_check(netdev_tstamp_prequeue, skb);
3240 trace_netif_rx(skb);
3242 if (static_key_false(&rps_needed)) {
3243 struct rps_dev_flow voidflow, *rflow = &voidflow;
3249 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3251 cpu = smp_processor_id();
3253 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3261 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3268 * netif_rx - post buffer to the network code
3269 * @skb: buffer to post
3271 * This function receives a packet from a device driver and queues it for
3272 * the upper (protocol) levels to process. It always succeeds. The buffer
3273 * may be dropped during processing for congestion control or by the
3277 * NET_RX_SUCCESS (no congestion)
3278 * NET_RX_DROP (packet was dropped)
3282 int netif_rx(struct sk_buff *skb)
3284 trace_netif_rx_entry(skb);
3286 return netif_rx_internal(skb);
3288 EXPORT_SYMBOL(netif_rx);
3290 int netif_rx_ni(struct sk_buff *skb)
3294 trace_netif_rx_ni_entry(skb);
3297 err = netif_rx_internal(skb);
3298 if (local_softirq_pending())
3304 EXPORT_SYMBOL(netif_rx_ni);
3306 static void net_tx_action(struct softirq_action *h)
3308 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3310 if (sd->completion_queue) {
3311 struct sk_buff *clist;
3313 local_irq_disable();
3314 clist = sd->completion_queue;
3315 sd->completion_queue = NULL;
3319 struct sk_buff *skb = clist;
3320 clist = clist->next;
3322 WARN_ON(atomic_read(&skb->users));
3323 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3324 trace_consume_skb(skb);
3326 trace_kfree_skb(skb, net_tx_action);
3331 if (sd->output_queue) {
3334 local_irq_disable();
3335 head = sd->output_queue;
3336 sd->output_queue = NULL;
3337 sd->output_queue_tailp = &sd->output_queue;
3341 struct Qdisc *q = head;
3342 spinlock_t *root_lock;
3344 head = head->next_sched;
3346 root_lock = qdisc_lock(q);
3347 if (spin_trylock(root_lock)) {
3348 smp_mb__before_clear_bit();
3349 clear_bit(__QDISC_STATE_SCHED,
3352 spin_unlock(root_lock);
3354 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3356 __netif_reschedule(q);
3358 smp_mb__before_clear_bit();
3359 clear_bit(__QDISC_STATE_SCHED,
3367 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3368 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3369 /* This hook is defined here for ATM LANE */
3370 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3371 unsigned char *addr) __read_mostly;
3372 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3375 #ifdef CONFIG_NET_CLS_ACT
3376 /* TODO: Maybe we should just force sch_ingress to be compiled in
3377 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3378 * a compare and 2 stores extra right now if we dont have it on
3379 * but have CONFIG_NET_CLS_ACT
3380 * NOTE: This doesn't stop any functionality; if you dont have
3381 * the ingress scheduler, you just can't add policies on ingress.
3384 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3386 struct net_device *dev = skb->dev;
3387 u32 ttl = G_TC_RTTL(skb->tc_verd);
3388 int result = TC_ACT_OK;
3391 if (unlikely(MAX_RED_LOOP < ttl++)) {
3392 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3393 skb->skb_iif, dev->ifindex);
3397 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3398 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3401 if (q != &noop_qdisc) {
3402 spin_lock(qdisc_lock(q));
3403 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3404 result = qdisc_enqueue_root(skb, q);
3405 spin_unlock(qdisc_lock(q));
3411 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3412 struct packet_type **pt_prev,
3413 int *ret, struct net_device *orig_dev)
3415 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3417 if (!rxq || rxq->qdisc == &noop_qdisc)
3421 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3425 switch (ing_filter(skb, rxq)) {
3439 * netdev_rx_handler_register - register receive handler
3440 * @dev: device to register a handler for
3441 * @rx_handler: receive handler to register
3442 * @rx_handler_data: data pointer that is used by rx handler
3444 * Register a receive hander for a device. This handler will then be
3445 * called from __netif_receive_skb. A negative errno code is returned
3448 * The caller must hold the rtnl_mutex.
3450 * For a general description of rx_handler, see enum rx_handler_result.
3452 int netdev_rx_handler_register(struct net_device *dev,
3453 rx_handler_func_t *rx_handler,
3454 void *rx_handler_data)
3458 if (dev->rx_handler)
3461 /* Note: rx_handler_data must be set before rx_handler */
3462 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3463 rcu_assign_pointer(dev->rx_handler, rx_handler);
3467 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3470 * netdev_rx_handler_unregister - unregister receive handler
3471 * @dev: device to unregister a handler from
3473 * Unregister a receive handler from a device.
3475 * The caller must hold the rtnl_mutex.
3477 void netdev_rx_handler_unregister(struct net_device *dev)
3481 RCU_INIT_POINTER(dev->rx_handler, NULL);
3482 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3483 * section has a guarantee to see a non NULL rx_handler_data
3487 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3489 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3492 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3493 * the special handling of PFMEMALLOC skbs.
3495 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3497 switch (skb->protocol) {
3498 case __constant_htons(ETH_P_ARP):
3499 case __constant_htons(ETH_P_IP):
3500 case __constant_htons(ETH_P_IPV6):
3501 case __constant_htons(ETH_P_8021Q):
3502 case __constant_htons(ETH_P_8021AD):
3509 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3511 struct packet_type *ptype, *pt_prev;
3512 rx_handler_func_t *rx_handler;
3513 struct net_device *orig_dev;
3514 struct net_device *null_or_dev;
3515 bool deliver_exact = false;
3516 int ret = NET_RX_DROP;
3519 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3521 trace_netif_receive_skb(skb);
3523 /* if we've gotten here through NAPI, check netpoll */
3524 if (netpoll_receive_skb(skb))
3527 orig_dev = skb->dev;
3529 skb_reset_network_header(skb);
3530 if (!skb_transport_header_was_set(skb))
3531 skb_reset_transport_header(skb);
3532 skb_reset_mac_len(skb);
3539 skb->skb_iif = skb->dev->ifindex;
3541 __this_cpu_inc(softnet_data.processed);
3543 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3544 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3545 skb = vlan_untag(skb);
3550 #ifdef CONFIG_NET_CLS_ACT
3551 if (skb->tc_verd & TC_NCLS) {
3552 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3560 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3561 if (!ptype->dev || ptype->dev == skb->dev) {
3563 ret = deliver_skb(skb, pt_prev, orig_dev);
3569 #ifdef CONFIG_NET_CLS_ACT
3570 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3576 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3579 if (vlan_tx_tag_present(skb)) {
3581 ret = deliver_skb(skb, pt_prev, orig_dev);
3584 if (vlan_do_receive(&skb))
3586 else if (unlikely(!skb))
3590 rx_handler = rcu_dereference(skb->dev->rx_handler);
3593 ret = deliver_skb(skb, pt_prev, orig_dev);
3596 switch (rx_handler(&skb)) {
3597 case RX_HANDLER_CONSUMED:
3598 ret = NET_RX_SUCCESS;
3600 case RX_HANDLER_ANOTHER:
3602 case RX_HANDLER_EXACT:
3603 deliver_exact = true;
3604 case RX_HANDLER_PASS:
3611 if (unlikely(vlan_tx_tag_present(skb))) {
3612 if (vlan_tx_tag_get_id(skb))
3613 skb->pkt_type = PACKET_OTHERHOST;
3614 /* Note: we might in the future use prio bits
3615 * and set skb->priority like in vlan_do_receive()
3616 * For the time being, just ignore Priority Code Point
3621 /* deliver only exact match when indicated */
3622 null_or_dev = deliver_exact ? skb->dev : NULL;
3624 type = skb->protocol;
3625 list_for_each_entry_rcu(ptype,
3626 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3627 if (ptype->type == type &&
3628 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3629 ptype->dev == orig_dev)) {
3631 ret = deliver_skb(skb, pt_prev, orig_dev);
3637 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3640 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3643 atomic_long_inc(&skb->dev->rx_dropped);
3645 /* Jamal, now you will not able to escape explaining
3646 * me how you were going to use this. :-)
3657 static int __netif_receive_skb(struct sk_buff *skb)
3661 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3662 unsigned long pflags = current->flags;
3665 * PFMEMALLOC skbs are special, they should
3666 * - be delivered to SOCK_MEMALLOC sockets only
3667 * - stay away from userspace
3668 * - have bounded memory usage
3670 * Use PF_MEMALLOC as this saves us from propagating the allocation
3671 * context down to all allocation sites.
3673 current->flags |= PF_MEMALLOC;
3674 ret = __netif_receive_skb_core(skb, true);
3675 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3677 ret = __netif_receive_skb_core(skb, false);
3682 static int netif_receive_skb_internal(struct sk_buff *skb)
3684 net_timestamp_check(netdev_tstamp_prequeue, skb);
3686 if (skb_defer_rx_timestamp(skb))
3687 return NET_RX_SUCCESS;
3690 if (static_key_false(&rps_needed)) {
3691 struct rps_dev_flow voidflow, *rflow = &voidflow;
3696 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3699 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3706 return __netif_receive_skb(skb);
3710 * netif_receive_skb - process receive buffer from network
3711 * @skb: buffer to process
3713 * netif_receive_skb() is the main receive data processing function.
3714 * It always succeeds. The buffer may be dropped during processing
3715 * for congestion control or by the protocol layers.
3717 * This function may only be called from softirq context and interrupts
3718 * should be enabled.
3720 * Return values (usually ignored):
3721 * NET_RX_SUCCESS: no congestion
3722 * NET_RX_DROP: packet was dropped
3724 int netif_receive_skb(struct sk_buff *skb)
3726 trace_netif_receive_skb_entry(skb);
3728 return netif_receive_skb_internal(skb);
3730 EXPORT_SYMBOL(netif_receive_skb);
3732 /* Network device is going away, flush any packets still pending
3733 * Called with irqs disabled.
3735 static void flush_backlog(void *arg)
3737 struct net_device *dev = arg;
3738 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3739 struct sk_buff *skb, *tmp;
3742 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3743 if (skb->dev == dev) {
3744 __skb_unlink(skb, &sd->input_pkt_queue);
3746 input_queue_head_incr(sd);
3751 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3752 if (skb->dev == dev) {
3753 __skb_unlink(skb, &sd->process_queue);
3755 input_queue_head_incr(sd);
3760 static int napi_gro_complete(struct sk_buff *skb)
3762 struct packet_offload *ptype;
3763 __be16 type = skb->protocol;
3764 struct list_head *head = &offload_base;
3767 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3769 if (NAPI_GRO_CB(skb)->count == 1) {
3770 skb_shinfo(skb)->gso_size = 0;
3775 list_for_each_entry_rcu(ptype, head, list) {
3776 if (ptype->type != type || !ptype->callbacks.gro_complete)
3779 err = ptype->callbacks.gro_complete(skb, 0);
3785 WARN_ON(&ptype->list == head);
3787 return NET_RX_SUCCESS;
3791 return netif_receive_skb_internal(skb);
3794 /* napi->gro_list contains packets ordered by age.
3795 * youngest packets at the head of it.
3796 * Complete skbs in reverse order to reduce latencies.
3798 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3800 struct sk_buff *skb, *prev = NULL;
3802 /* scan list and build reverse chain */
3803 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3808 for (skb = prev; skb; skb = prev) {
3811 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3815 napi_gro_complete(skb);
3819 napi->gro_list = NULL;
3821 EXPORT_SYMBOL(napi_gro_flush);
3823 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3826 unsigned int maclen = skb->dev->hard_header_len;
3827 u32 hash = skb_get_hash_raw(skb);
3829 for (p = napi->gro_list; p; p = p->next) {
3830 unsigned long diffs;
3832 NAPI_GRO_CB(p)->flush = 0;
3834 if (hash != skb_get_hash_raw(p)) {
3835 NAPI_GRO_CB(p)->same_flow = 0;
3839 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3840 diffs |= p->vlan_tci ^ skb->vlan_tci;
3841 if (maclen == ETH_HLEN)
3842 diffs |= compare_ether_header(skb_mac_header(p),
3843 skb_gro_mac_header(skb));
3845 diffs = memcmp(skb_mac_header(p),
3846 skb_gro_mac_header(skb),
3848 NAPI_GRO_CB(p)->same_flow = !diffs;
3852 static void skb_gro_reset_offset(struct sk_buff *skb)
3854 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3855 const skb_frag_t *frag0 = &pinfo->frags[0];
3857 NAPI_GRO_CB(skb)->data_offset = 0;
3858 NAPI_GRO_CB(skb)->frag0 = NULL;
3859 NAPI_GRO_CB(skb)->frag0_len = 0;
3861 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3863 !PageHighMem(skb_frag_page(frag0))) {
3864 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3865 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3869 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3871 struct sk_buff **pp = NULL;
3872 struct packet_offload *ptype;
3873 __be16 type = skb->protocol;
3874 struct list_head *head = &offload_base;
3876 enum gro_result ret;
3878 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3881 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3884 skb_gro_reset_offset(skb);
3885 gro_list_prepare(napi, skb);
3886 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3889 list_for_each_entry_rcu(ptype, head, list) {
3890 if (ptype->type != type || !ptype->callbacks.gro_receive)
3893 skb_set_network_header(skb, skb_gro_offset(skb));
3894 skb_reset_mac_len(skb);
3895 NAPI_GRO_CB(skb)->same_flow = 0;
3896 NAPI_GRO_CB(skb)->flush = 0;
3897 NAPI_GRO_CB(skb)->free = 0;
3898 NAPI_GRO_CB(skb)->udp_mark = 0;
3900 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3905 if (&ptype->list == head)
3908 same_flow = NAPI_GRO_CB(skb)->same_flow;
3909 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3912 struct sk_buff *nskb = *pp;
3916 napi_gro_complete(nskb);
3923 if (NAPI_GRO_CB(skb)->flush)
3926 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
3927 struct sk_buff *nskb = napi->gro_list;
3929 /* locate the end of the list to select the 'oldest' flow */
3930 while (nskb->next) {
3936 napi_gro_complete(nskb);
3940 NAPI_GRO_CB(skb)->count = 1;
3941 NAPI_GRO_CB(skb)->age = jiffies;
3942 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3943 skb->next = napi->gro_list;
3944 napi->gro_list = skb;
3948 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3949 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3951 BUG_ON(skb->end - skb->tail < grow);
3953 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3956 skb->data_len -= grow;
3958 skb_shinfo(skb)->frags[0].page_offset += grow;
3959 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3961 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3962 skb_frag_unref(skb, 0);
3963 memmove(skb_shinfo(skb)->frags,
3964 skb_shinfo(skb)->frags + 1,
3965 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3977 struct packet_offload *gro_find_receive_by_type(__be16 type)
3979 struct list_head *offload_head = &offload_base;
3980 struct packet_offload *ptype;
3982 list_for_each_entry_rcu(ptype, offload_head, list) {
3983 if (ptype->type != type || !ptype->callbacks.gro_receive)
3989 EXPORT_SYMBOL(gro_find_receive_by_type);
3991 struct packet_offload *gro_find_complete_by_type(__be16 type)
3993 struct list_head *offload_head = &offload_base;
3994 struct packet_offload *ptype;
3996 list_for_each_entry_rcu(ptype, offload_head, list) {
3997 if (ptype->type != type || !ptype->callbacks.gro_complete)
4003 EXPORT_SYMBOL(gro_find_complete_by_type);
4005 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4009 if (netif_receive_skb_internal(skb))
4017 case GRO_MERGED_FREE:
4018 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
4019 kmem_cache_free(skbuff_head_cache, skb);
4032 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4034 trace_napi_gro_receive_entry(skb);
4036 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4038 EXPORT_SYMBOL(napi_gro_receive);
4040 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4042 __skb_pull(skb, skb_headlen(skb));
4043 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4044 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4046 skb->dev = napi->dev;
4052 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4054 struct sk_buff *skb = napi->skb;
4057 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4062 EXPORT_SYMBOL(napi_get_frags);
4064 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
4069 if (netif_receive_skb_internal(skb))
4074 case GRO_MERGED_FREE:
4075 napi_reuse_skb(napi, skb);
4086 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4088 struct sk_buff *skb = napi->skb;
4092 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4093 napi_reuse_skb(napi, skb);
4096 skb->protocol = eth_type_trans(skb, skb->dev);
4101 gro_result_t napi_gro_frags(struct napi_struct *napi)
4103 struct sk_buff *skb = napi_frags_skb(napi);
4108 trace_napi_gro_frags_entry(skb);
4110 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4112 EXPORT_SYMBOL(napi_gro_frags);
4115 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4116 * Note: called with local irq disabled, but exits with local irq enabled.
4118 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4121 struct softnet_data *remsd = sd->rps_ipi_list;
4124 sd->rps_ipi_list = NULL;
4128 /* Send pending IPI's to kick RPS processing on remote cpus. */
4130 struct softnet_data *next = remsd->rps_ipi_next;
4132 if (cpu_online(remsd->cpu))
4133 __smp_call_function_single(remsd->cpu,
4142 static int process_backlog(struct napi_struct *napi, int quota)
4145 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4148 /* Check if we have pending ipi, its better to send them now,
4149 * not waiting net_rx_action() end.
4151 if (sd->rps_ipi_list) {
4152 local_irq_disable();
4153 net_rps_action_and_irq_enable(sd);
4156 napi->weight = weight_p;
4157 local_irq_disable();
4158 while (work < quota) {
4159 struct sk_buff *skb;
4162 while ((skb = __skb_dequeue(&sd->process_queue))) {
4164 __netif_receive_skb(skb);
4165 local_irq_disable();
4166 input_queue_head_incr(sd);
4167 if (++work >= quota) {
4174 qlen = skb_queue_len(&sd->input_pkt_queue);
4176 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4177 &sd->process_queue);
4179 if (qlen < quota - work) {
4181 * Inline a custom version of __napi_complete().
4182 * only current cpu owns and manipulates this napi,
4183 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4184 * we can use a plain write instead of clear_bit(),
4185 * and we dont need an smp_mb() memory barrier.
4187 list_del(&napi->poll_list);
4190 quota = work + qlen;
4200 * __napi_schedule - schedule for receive
4201 * @n: entry to schedule
4203 * The entry's receive function will be scheduled to run
4205 void __napi_schedule(struct napi_struct *n)
4207 unsigned long flags;
4209 local_irq_save(flags);
4210 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4211 local_irq_restore(flags);
4213 EXPORT_SYMBOL(__napi_schedule);
4215 void __napi_complete(struct napi_struct *n)
4217 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4218 BUG_ON(n->gro_list);
4220 list_del(&n->poll_list);
4221 smp_mb__before_clear_bit();
4222 clear_bit(NAPI_STATE_SCHED, &n->state);
4224 EXPORT_SYMBOL(__napi_complete);
4226 void napi_complete(struct napi_struct *n)
4228 unsigned long flags;
4231 * don't let napi dequeue from the cpu poll list
4232 * just in case its running on a different cpu
4234 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4237 napi_gro_flush(n, false);
4238 local_irq_save(flags);
4240 local_irq_restore(flags);
4242 EXPORT_SYMBOL(napi_complete);
4244 /* must be called under rcu_read_lock(), as we dont take a reference */
4245 struct napi_struct *napi_by_id(unsigned int napi_id)
4247 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4248 struct napi_struct *napi;
4250 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4251 if (napi->napi_id == napi_id)
4256 EXPORT_SYMBOL_GPL(napi_by_id);
4258 void napi_hash_add(struct napi_struct *napi)
4260 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4262 spin_lock(&napi_hash_lock);
4264 /* 0 is not a valid id, we also skip an id that is taken
4265 * we expect both events to be extremely rare
4268 while (!napi->napi_id) {
4269 napi->napi_id = ++napi_gen_id;
4270 if (napi_by_id(napi->napi_id))
4274 hlist_add_head_rcu(&napi->napi_hash_node,
4275 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4277 spin_unlock(&napi_hash_lock);
4280 EXPORT_SYMBOL_GPL(napi_hash_add);
4282 /* Warning : caller is responsible to make sure rcu grace period
4283 * is respected before freeing memory containing @napi
4285 void napi_hash_del(struct napi_struct *napi)
4287 spin_lock(&napi_hash_lock);
4289 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4290 hlist_del_rcu(&napi->napi_hash_node);
4292 spin_unlock(&napi_hash_lock);
4294 EXPORT_SYMBOL_GPL(napi_hash_del);
4296 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4297 int (*poll)(struct napi_struct *, int), int weight)
4299 INIT_LIST_HEAD(&napi->poll_list);
4300 napi->gro_count = 0;
4301 napi->gro_list = NULL;
4304 if (weight > NAPI_POLL_WEIGHT)
4305 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4307 napi->weight = weight;
4308 list_add(&napi->dev_list, &dev->napi_list);
4310 #ifdef CONFIG_NETPOLL
4311 spin_lock_init(&napi->poll_lock);
4312 napi->poll_owner = -1;
4314 set_bit(NAPI_STATE_SCHED, &napi->state);
4316 EXPORT_SYMBOL(netif_napi_add);
4318 void netif_napi_del(struct napi_struct *napi)
4320 list_del_init(&napi->dev_list);
4321 napi_free_frags(napi);
4323 kfree_skb_list(napi->gro_list);
4324 napi->gro_list = NULL;
4325 napi->gro_count = 0;
4327 EXPORT_SYMBOL(netif_napi_del);
4329 static void net_rx_action(struct softirq_action *h)
4331 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4332 unsigned long time_limit = jiffies + 2;
4333 int budget = netdev_budget;
4336 local_irq_disable();
4338 while (!list_empty(&sd->poll_list)) {
4339 struct napi_struct *n;
4342 /* If softirq window is exhuasted then punt.
4343 * Allow this to run for 2 jiffies since which will allow
4344 * an average latency of 1.5/HZ.
4346 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4351 /* Even though interrupts have been re-enabled, this
4352 * access is safe because interrupts can only add new
4353 * entries to the tail of this list, and only ->poll()
4354 * calls can remove this head entry from the list.
4356 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4358 have = netpoll_poll_lock(n);
4362 /* This NAPI_STATE_SCHED test is for avoiding a race
4363 * with netpoll's poll_napi(). Only the entity which
4364 * obtains the lock and sees NAPI_STATE_SCHED set will
4365 * actually make the ->poll() call. Therefore we avoid
4366 * accidentally calling ->poll() when NAPI is not scheduled.
4369 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4370 work = n->poll(n, weight);
4374 WARN_ON_ONCE(work > weight);
4378 local_irq_disable();
4380 /* Drivers must not modify the NAPI state if they
4381 * consume the entire weight. In such cases this code
4382 * still "owns" the NAPI instance and therefore can
4383 * move the instance around on the list at-will.
4385 if (unlikely(work == weight)) {
4386 if (unlikely(napi_disable_pending(n))) {
4389 local_irq_disable();
4392 /* flush too old packets
4393 * If HZ < 1000, flush all packets.
4396 napi_gro_flush(n, HZ >= 1000);
4397 local_irq_disable();
4399 list_move_tail(&n->poll_list, &sd->poll_list);
4403 netpoll_poll_unlock(have);
4406 net_rps_action_and_irq_enable(sd);
4408 #ifdef CONFIG_NET_DMA
4410 * There may not be any more sk_buffs coming right now, so push
4411 * any pending DMA copies to hardware
4413 dma_issue_pending_all();
4420 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4424 struct netdev_adjacent {
4425 struct net_device *dev;
4427 /* upper master flag, there can only be one master device per list */
4430 /* counter for the number of times this device was added to us */
4433 /* private field for the users */
4436 struct list_head list;
4437 struct rcu_head rcu;
4440 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4441 struct net_device *adj_dev,
4442 struct list_head *adj_list)
4444 struct netdev_adjacent *adj;
4446 list_for_each_entry(adj, adj_list, list) {
4447 if (adj->dev == adj_dev)
4454 * netdev_has_upper_dev - Check if device is linked to an upper device
4456 * @upper_dev: upper device to check
4458 * Find out if a device is linked to specified upper device and return true
4459 * in case it is. Note that this checks only immediate upper device,
4460 * not through a complete stack of devices. The caller must hold the RTNL lock.
4462 bool netdev_has_upper_dev(struct net_device *dev,
4463 struct net_device *upper_dev)
4467 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4469 EXPORT_SYMBOL(netdev_has_upper_dev);
4472 * netdev_has_any_upper_dev - Check if device is linked to some device
4475 * Find out if a device is linked to an upper device and return true in case
4476 * it is. The caller must hold the RTNL lock.
4478 static bool netdev_has_any_upper_dev(struct net_device *dev)
4482 return !list_empty(&dev->all_adj_list.upper);
4486 * netdev_master_upper_dev_get - Get master upper device
4489 * Find a master upper device and return pointer to it or NULL in case
4490 * it's not there. The caller must hold the RTNL lock.
4492 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4494 struct netdev_adjacent *upper;
4498 if (list_empty(&dev->adj_list.upper))
4501 upper = list_first_entry(&dev->adj_list.upper,
4502 struct netdev_adjacent, list);
4503 if (likely(upper->master))
4507 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4509 void *netdev_adjacent_get_private(struct list_head *adj_list)
4511 struct netdev_adjacent *adj;
4513 adj = list_entry(adj_list, struct netdev_adjacent, list);
4515 return adj->private;
4517 EXPORT_SYMBOL(netdev_adjacent_get_private);
4520 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4522 * @iter: list_head ** of the current position
4524 * Gets the next device from the dev's upper list, starting from iter
4525 * position. The caller must hold RCU read lock.
4527 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4528 struct list_head **iter)
4530 struct netdev_adjacent *upper;
4532 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4534 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4536 if (&upper->list == &dev->all_adj_list.upper)
4539 *iter = &upper->list;
4543 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4546 * netdev_lower_get_next_private - Get the next ->private from the
4547 * lower neighbour list
4549 * @iter: list_head ** of the current position
4551 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4552 * list, starting from iter position. The caller must hold either hold the
4553 * RTNL lock or its own locking that guarantees that the neighbour lower
4554 * list will remain unchainged.
4556 void *netdev_lower_get_next_private(struct net_device *dev,
4557 struct list_head **iter)
4559 struct netdev_adjacent *lower;
4561 lower = list_entry(*iter, struct netdev_adjacent, list);
4563 if (&lower->list == &dev->adj_list.lower)
4567 *iter = lower->list.next;
4569 return lower->private;
4571 EXPORT_SYMBOL(netdev_lower_get_next_private);
4574 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4575 * lower neighbour list, RCU
4578 * @iter: list_head ** of the current position
4580 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4581 * list, starting from iter position. The caller must hold RCU read lock.
4583 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4584 struct list_head **iter)
4586 struct netdev_adjacent *lower;
4588 WARN_ON_ONCE(!rcu_read_lock_held());
4590 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4592 if (&lower->list == &dev->adj_list.lower)
4596 *iter = &lower->list;
4598 return lower->private;
4600 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4603 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4604 * lower neighbour list, RCU
4608 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4609 * list. The caller must hold RCU read lock.
4611 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4613 struct netdev_adjacent *lower;
4615 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4616 struct netdev_adjacent, list);
4618 return lower->private;
4621 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4624 * netdev_master_upper_dev_get_rcu - Get master upper device
4627 * Find a master upper device and return pointer to it or NULL in case
4628 * it's not there. The caller must hold the RCU read lock.
4630 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4632 struct netdev_adjacent *upper;
4634 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4635 struct netdev_adjacent, list);
4636 if (upper && likely(upper->master))
4640 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4642 static int netdev_adjacent_sysfs_add(struct net_device *dev,
4643 struct net_device *adj_dev,
4644 struct list_head *dev_list)
4646 char linkname[IFNAMSIZ+7];
4647 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4648 "upper_%s" : "lower_%s", adj_dev->name);
4649 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
4652 static void netdev_adjacent_sysfs_del(struct net_device *dev,
4654 struct list_head *dev_list)
4656 char linkname[IFNAMSIZ+7];
4657 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4658 "upper_%s" : "lower_%s", name);
4659 sysfs_remove_link(&(dev->dev.kobj), linkname);
4662 #define netdev_adjacent_is_neigh_list(dev, dev_list) \
4663 (dev_list == &dev->adj_list.upper || \
4664 dev_list == &dev->adj_list.lower)
4666 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4667 struct net_device *adj_dev,
4668 struct list_head *dev_list,
4669 void *private, bool master)
4671 struct netdev_adjacent *adj;
4674 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4681 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4686 adj->master = master;
4688 adj->private = private;
4691 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4692 adj_dev->name, dev->name, adj_dev->name);
4694 if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
4695 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
4700 /* Ensure that master link is always the first item in list. */
4702 ret = sysfs_create_link(&(dev->dev.kobj),
4703 &(adj_dev->dev.kobj), "master");
4705 goto remove_symlinks;
4707 list_add_rcu(&adj->list, dev_list);
4709 list_add_tail_rcu(&adj->list, dev_list);
4715 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4716 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4724 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4725 struct net_device *adj_dev,
4726 struct list_head *dev_list)
4728 struct netdev_adjacent *adj;
4730 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4733 pr_err("tried to remove device %s from %s\n",
4734 dev->name, adj_dev->name);
4738 if (adj->ref_nr > 1) {
4739 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4746 sysfs_remove_link(&(dev->dev.kobj), "master");
4748 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4749 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4751 list_del_rcu(&adj->list);
4752 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4753 adj_dev->name, dev->name, adj_dev->name);
4755 kfree_rcu(adj, rcu);
4758 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4759 struct net_device *upper_dev,
4760 struct list_head *up_list,
4761 struct list_head *down_list,
4762 void *private, bool master)
4766 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4771 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4774 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4781 static int __netdev_adjacent_dev_link(struct net_device *dev,
4782 struct net_device *upper_dev)
4784 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4785 &dev->all_adj_list.upper,
4786 &upper_dev->all_adj_list.lower,
4790 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4791 struct net_device *upper_dev,
4792 struct list_head *up_list,
4793 struct list_head *down_list)
4795 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4796 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4799 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4800 struct net_device *upper_dev)
4802 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4803 &dev->all_adj_list.upper,
4804 &upper_dev->all_adj_list.lower);
4807 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4808 struct net_device *upper_dev,
4809 void *private, bool master)
4811 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4816 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4817 &dev->adj_list.upper,
4818 &upper_dev->adj_list.lower,
4821 __netdev_adjacent_dev_unlink(dev, upper_dev);
4828 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4829 struct net_device *upper_dev)
4831 __netdev_adjacent_dev_unlink(dev, upper_dev);
4832 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4833 &dev->adj_list.upper,
4834 &upper_dev->adj_list.lower);
4837 static int __netdev_upper_dev_link(struct net_device *dev,
4838 struct net_device *upper_dev, bool master,
4841 struct netdev_adjacent *i, *j, *to_i, *to_j;
4846 if (dev == upper_dev)
4849 /* To prevent loops, check if dev is not upper device to upper_dev. */
4850 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4853 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4856 if (master && netdev_master_upper_dev_get(dev))
4859 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4864 /* Now that we linked these devs, make all the upper_dev's
4865 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4866 * versa, and don't forget the devices itself. All of these
4867 * links are non-neighbours.
4869 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4870 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4871 pr_debug("Interlinking %s with %s, non-neighbour\n",
4872 i->dev->name, j->dev->name);
4873 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4879 /* add dev to every upper_dev's upper device */
4880 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4881 pr_debug("linking %s's upper device %s with %s\n",
4882 upper_dev->name, i->dev->name, dev->name);
4883 ret = __netdev_adjacent_dev_link(dev, i->dev);
4885 goto rollback_upper_mesh;
4888 /* add upper_dev to every dev's lower device */
4889 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4890 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4891 i->dev->name, upper_dev->name);
4892 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4894 goto rollback_lower_mesh;
4897 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4900 rollback_lower_mesh:
4902 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4905 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4910 rollback_upper_mesh:
4912 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4915 __netdev_adjacent_dev_unlink(dev, i->dev);
4923 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4924 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4925 if (i == to_i && j == to_j)
4927 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4933 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4939 * netdev_upper_dev_link - Add a link to the upper device
4941 * @upper_dev: new upper device
4943 * Adds a link to device which is upper to this one. The caller must hold
4944 * the RTNL lock. On a failure a negative errno code is returned.
4945 * On success the reference counts are adjusted and the function
4948 int netdev_upper_dev_link(struct net_device *dev,
4949 struct net_device *upper_dev)
4951 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4953 EXPORT_SYMBOL(netdev_upper_dev_link);
4956 * netdev_master_upper_dev_link - Add a master link to the upper device
4958 * @upper_dev: new upper device
4960 * Adds a link to device which is upper to this one. In this case, only
4961 * one master upper device can be linked, although other non-master devices
4962 * might be linked as well. The caller must hold the RTNL lock.
4963 * On a failure a negative errno code is returned. On success the reference
4964 * counts are adjusted and the function returns zero.
4966 int netdev_master_upper_dev_link(struct net_device *dev,
4967 struct net_device *upper_dev)
4969 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4971 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4973 int netdev_master_upper_dev_link_private(struct net_device *dev,
4974 struct net_device *upper_dev,
4977 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4979 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4982 * netdev_upper_dev_unlink - Removes a link to upper device
4984 * @upper_dev: new upper device
4986 * Removes a link to device which is upper to this one. The caller must hold
4989 void netdev_upper_dev_unlink(struct net_device *dev,
4990 struct net_device *upper_dev)
4992 struct netdev_adjacent *i, *j;
4995 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4997 /* Here is the tricky part. We must remove all dev's lower
4998 * devices from all upper_dev's upper devices and vice
4999 * versa, to maintain the graph relationship.
5001 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5002 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5003 __netdev_adjacent_dev_unlink(i->dev, j->dev);
5005 /* remove also the devices itself from lower/upper device
5008 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5009 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
5011 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5012 __netdev_adjacent_dev_unlink(dev, i->dev);
5014 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5016 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5018 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5020 struct netdev_adjacent *iter;
5022 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5023 netdev_adjacent_sysfs_del(iter->dev, oldname,
5024 &iter->dev->adj_list.lower);
5025 netdev_adjacent_sysfs_add(iter->dev, dev,
5026 &iter->dev->adj_list.lower);
5029 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5030 netdev_adjacent_sysfs_del(iter->dev, oldname,
5031 &iter->dev->adj_list.upper);
5032 netdev_adjacent_sysfs_add(iter->dev, dev,
5033 &iter->dev->adj_list.upper);
5037 void *netdev_lower_dev_get_private(struct net_device *dev,
5038 struct net_device *lower_dev)
5040 struct netdev_adjacent *lower;
5044 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
5048 return lower->private;
5050 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5052 static void dev_change_rx_flags(struct net_device *dev, int flags)
5054 const struct net_device_ops *ops = dev->netdev_ops;
5056 if (ops->ndo_change_rx_flags)
5057 ops->ndo_change_rx_flags(dev, flags);
5060 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5062 unsigned int old_flags = dev->flags;
5068 dev->flags |= IFF_PROMISC;
5069 dev->promiscuity += inc;
5070 if (dev->promiscuity == 0) {
5073 * If inc causes overflow, untouch promisc and return error.
5076 dev->flags &= ~IFF_PROMISC;
5078 dev->promiscuity -= inc;
5079 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5084 if (dev->flags != old_flags) {
5085 pr_info("device %s %s promiscuous mode\n",
5087 dev->flags & IFF_PROMISC ? "entered" : "left");
5088 if (audit_enabled) {
5089 current_uid_gid(&uid, &gid);
5090 audit_log(current->audit_context, GFP_ATOMIC,
5091 AUDIT_ANOM_PROMISCUOUS,
5092 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5093 dev->name, (dev->flags & IFF_PROMISC),
5094 (old_flags & IFF_PROMISC),
5095 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5096 from_kuid(&init_user_ns, uid),
5097 from_kgid(&init_user_ns, gid),
5098 audit_get_sessionid(current));
5101 dev_change_rx_flags(dev, IFF_PROMISC);
5104 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5109 * dev_set_promiscuity - update promiscuity count on a device
5113 * Add or remove promiscuity from a device. While the count in the device
5114 * remains above zero the interface remains promiscuous. Once it hits zero
5115 * the device reverts back to normal filtering operation. A negative inc
5116 * value is used to drop promiscuity on the device.
5117 * Return 0 if successful or a negative errno code on error.
5119 int dev_set_promiscuity(struct net_device *dev, int inc)
5121 unsigned int old_flags = dev->flags;
5124 err = __dev_set_promiscuity(dev, inc, true);
5127 if (dev->flags != old_flags)
5128 dev_set_rx_mode(dev);
5131 EXPORT_SYMBOL(dev_set_promiscuity);
5133 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5135 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5139 dev->flags |= IFF_ALLMULTI;
5140 dev->allmulti += inc;
5141 if (dev->allmulti == 0) {
5144 * If inc causes overflow, untouch allmulti and return error.
5147 dev->flags &= ~IFF_ALLMULTI;
5149 dev->allmulti -= inc;
5150 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5155 if (dev->flags ^ old_flags) {
5156 dev_change_rx_flags(dev, IFF_ALLMULTI);
5157 dev_set_rx_mode(dev);
5159 __dev_notify_flags(dev, old_flags,
5160 dev->gflags ^ old_gflags);
5166 * dev_set_allmulti - update allmulti count on a device
5170 * Add or remove reception of all multicast frames to a device. While the
5171 * count in the device remains above zero the interface remains listening
5172 * to all interfaces. Once it hits zero the device reverts back to normal
5173 * filtering operation. A negative @inc value is used to drop the counter
5174 * when releasing a resource needing all multicasts.
5175 * Return 0 if successful or a negative errno code on error.
5178 int dev_set_allmulti(struct net_device *dev, int inc)
5180 return __dev_set_allmulti(dev, inc, true);
5182 EXPORT_SYMBOL(dev_set_allmulti);
5185 * Upload unicast and multicast address lists to device and
5186 * configure RX filtering. When the device doesn't support unicast
5187 * filtering it is put in promiscuous mode while unicast addresses
5190 void __dev_set_rx_mode(struct net_device *dev)
5192 const struct net_device_ops *ops = dev->netdev_ops;
5194 /* dev_open will call this function so the list will stay sane. */
5195 if (!(dev->flags&IFF_UP))
5198 if (!netif_device_present(dev))
5201 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5202 /* Unicast addresses changes may only happen under the rtnl,
5203 * therefore calling __dev_set_promiscuity here is safe.
5205 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5206 __dev_set_promiscuity(dev, 1, false);
5207 dev->uc_promisc = true;
5208 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5209 __dev_set_promiscuity(dev, -1, false);
5210 dev->uc_promisc = false;
5214 if (ops->ndo_set_rx_mode)
5215 ops->ndo_set_rx_mode(dev);
5218 void dev_set_rx_mode(struct net_device *dev)
5220 netif_addr_lock_bh(dev);
5221 __dev_set_rx_mode(dev);
5222 netif_addr_unlock_bh(dev);
5226 * dev_get_flags - get flags reported to userspace
5229 * Get the combination of flag bits exported through APIs to userspace.
5231 unsigned int dev_get_flags(const struct net_device *dev)
5235 flags = (dev->flags & ~(IFF_PROMISC |
5240 (dev->gflags & (IFF_PROMISC |
5243 if (netif_running(dev)) {
5244 if (netif_oper_up(dev))
5245 flags |= IFF_RUNNING;
5246 if (netif_carrier_ok(dev))
5247 flags |= IFF_LOWER_UP;
5248 if (netif_dormant(dev))
5249 flags |= IFF_DORMANT;
5254 EXPORT_SYMBOL(dev_get_flags);
5256 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5258 unsigned int old_flags = dev->flags;
5264 * Set the flags on our device.
5267 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5268 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5270 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5274 * Load in the correct multicast list now the flags have changed.
5277 if ((old_flags ^ flags) & IFF_MULTICAST)
5278 dev_change_rx_flags(dev, IFF_MULTICAST);
5280 dev_set_rx_mode(dev);
5283 * Have we downed the interface. We handle IFF_UP ourselves
5284 * according to user attempts to set it, rather than blindly
5289 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5290 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5293 dev_set_rx_mode(dev);
5296 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5297 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5298 unsigned int old_flags = dev->flags;
5300 dev->gflags ^= IFF_PROMISC;
5302 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5303 if (dev->flags != old_flags)
5304 dev_set_rx_mode(dev);
5307 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5308 is important. Some (broken) drivers set IFF_PROMISC, when
5309 IFF_ALLMULTI is requested not asking us and not reporting.
5311 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5312 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5314 dev->gflags ^= IFF_ALLMULTI;
5315 __dev_set_allmulti(dev, inc, false);
5321 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5322 unsigned int gchanges)
5324 unsigned int changes = dev->flags ^ old_flags;
5327 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5329 if (changes & IFF_UP) {
5330 if (dev->flags & IFF_UP)
5331 call_netdevice_notifiers(NETDEV_UP, dev);
5333 call_netdevice_notifiers(NETDEV_DOWN, dev);
5336 if (dev->flags & IFF_UP &&
5337 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5338 struct netdev_notifier_change_info change_info;
5340 change_info.flags_changed = changes;
5341 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5347 * dev_change_flags - change device settings
5349 * @flags: device state flags
5351 * Change settings on device based state flags. The flags are
5352 * in the userspace exported format.
5354 int dev_change_flags(struct net_device *dev, unsigned int flags)
5357 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5359 ret = __dev_change_flags(dev, flags);
5363 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5364 __dev_notify_flags(dev, old_flags, changes);
5367 EXPORT_SYMBOL(dev_change_flags);
5369 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5371 const struct net_device_ops *ops = dev->netdev_ops;
5373 if (ops->ndo_change_mtu)
5374 return ops->ndo_change_mtu(dev, new_mtu);
5381 * dev_set_mtu - Change maximum transfer unit
5383 * @new_mtu: new transfer unit
5385 * Change the maximum transfer size of the network device.
5387 int dev_set_mtu(struct net_device *dev, int new_mtu)
5391 if (new_mtu == dev->mtu)
5394 /* MTU must be positive. */
5398 if (!netif_device_present(dev))
5401 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
5402 err = notifier_to_errno(err);
5406 orig_mtu = dev->mtu;
5407 err = __dev_set_mtu(dev, new_mtu);
5410 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5411 err = notifier_to_errno(err);
5413 /* setting mtu back and notifying everyone again,
5414 * so that they have a chance to revert changes.
5416 __dev_set_mtu(dev, orig_mtu);
5417 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5422 EXPORT_SYMBOL(dev_set_mtu);
5425 * dev_set_group - Change group this device belongs to
5427 * @new_group: group this device should belong to
5429 void dev_set_group(struct net_device *dev, int new_group)
5431 dev->group = new_group;
5433 EXPORT_SYMBOL(dev_set_group);
5436 * dev_set_mac_address - Change Media Access Control Address
5440 * Change the hardware (MAC) address of the device
5442 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5444 const struct net_device_ops *ops = dev->netdev_ops;
5447 if (!ops->ndo_set_mac_address)
5449 if (sa->sa_family != dev->type)
5451 if (!netif_device_present(dev))
5453 err = ops->ndo_set_mac_address(dev, sa);
5456 dev->addr_assign_type = NET_ADDR_SET;
5457 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5458 add_device_randomness(dev->dev_addr, dev->addr_len);
5461 EXPORT_SYMBOL(dev_set_mac_address);
5464 * dev_change_carrier - Change device carrier
5466 * @new_carrier: new value
5468 * Change device carrier
5470 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5472 const struct net_device_ops *ops = dev->netdev_ops;
5474 if (!ops->ndo_change_carrier)
5476 if (!netif_device_present(dev))
5478 return ops->ndo_change_carrier(dev, new_carrier);
5480 EXPORT_SYMBOL(dev_change_carrier);
5483 * dev_get_phys_port_id - Get device physical port ID
5487 * Get device physical port ID
5489 int dev_get_phys_port_id(struct net_device *dev,
5490 struct netdev_phys_port_id *ppid)
5492 const struct net_device_ops *ops = dev->netdev_ops;
5494 if (!ops->ndo_get_phys_port_id)
5496 return ops->ndo_get_phys_port_id(dev, ppid);
5498 EXPORT_SYMBOL(dev_get_phys_port_id);
5501 * dev_new_index - allocate an ifindex
5502 * @net: the applicable net namespace
5504 * Returns a suitable unique value for a new device interface
5505 * number. The caller must hold the rtnl semaphore or the
5506 * dev_base_lock to be sure it remains unique.
5508 static int dev_new_index(struct net *net)
5510 int ifindex = net->ifindex;
5514 if (!__dev_get_by_index(net, ifindex))
5515 return net->ifindex = ifindex;
5519 /* Delayed registration/unregisteration */
5520 static LIST_HEAD(net_todo_list);
5521 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5523 static void net_set_todo(struct net_device *dev)
5525 list_add_tail(&dev->todo_list, &net_todo_list);
5526 dev_net(dev)->dev_unreg_count++;
5529 static void rollback_registered_many(struct list_head *head)
5531 struct net_device *dev, *tmp;
5532 LIST_HEAD(close_head);
5534 BUG_ON(dev_boot_phase);
5537 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5538 /* Some devices call without registering
5539 * for initialization unwind. Remove those
5540 * devices and proceed with the remaining.
5542 if (dev->reg_state == NETREG_UNINITIALIZED) {
5543 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5547 list_del(&dev->unreg_list);
5550 dev->dismantle = true;
5551 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5554 /* If device is running, close it first. */
5555 list_for_each_entry(dev, head, unreg_list)
5556 list_add_tail(&dev->close_list, &close_head);
5557 dev_close_many(&close_head);
5559 list_for_each_entry(dev, head, unreg_list) {
5560 /* And unlink it from device chain. */
5561 unlist_netdevice(dev);
5563 dev->reg_state = NETREG_UNREGISTERING;
5568 list_for_each_entry(dev, head, unreg_list) {
5569 /* Shutdown queueing discipline. */
5573 /* Notify protocols, that we are about to destroy
5574 this device. They should clean all the things.
5576 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5578 if (!dev->rtnl_link_ops ||
5579 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5580 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5583 * Flush the unicast and multicast chains
5588 if (dev->netdev_ops->ndo_uninit)
5589 dev->netdev_ops->ndo_uninit(dev);
5591 /* Notifier chain MUST detach us all upper devices. */
5592 WARN_ON(netdev_has_any_upper_dev(dev));
5594 /* Remove entries from kobject tree */
5595 netdev_unregister_kobject(dev);
5597 /* Remove XPS queueing entries */
5598 netif_reset_xps_queues_gt(dev, 0);
5604 list_for_each_entry(dev, head, unreg_list)
5608 static void rollback_registered(struct net_device *dev)
5612 list_add(&dev->unreg_list, &single);
5613 rollback_registered_many(&single);
5617 static netdev_features_t netdev_fix_features(struct net_device *dev,
5618 netdev_features_t features)
5620 /* Fix illegal checksum combinations */
5621 if ((features & NETIF_F_HW_CSUM) &&
5622 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5623 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5624 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5627 /* TSO requires that SG is present as well. */
5628 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5629 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5630 features &= ~NETIF_F_ALL_TSO;
5633 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5634 !(features & NETIF_F_IP_CSUM)) {
5635 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5636 features &= ~NETIF_F_TSO;
5637 features &= ~NETIF_F_TSO_ECN;
5640 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5641 !(features & NETIF_F_IPV6_CSUM)) {
5642 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5643 features &= ~NETIF_F_TSO6;
5646 /* TSO ECN requires that TSO is present as well. */
5647 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5648 features &= ~NETIF_F_TSO_ECN;
5650 /* Software GSO depends on SG. */
5651 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5652 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5653 features &= ~NETIF_F_GSO;
5656 /* UFO needs SG and checksumming */
5657 if (features & NETIF_F_UFO) {
5658 /* maybe split UFO into V4 and V6? */
5659 if (!((features & NETIF_F_GEN_CSUM) ||
5660 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5661 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5663 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5664 features &= ~NETIF_F_UFO;
5667 if (!(features & NETIF_F_SG)) {
5669 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5670 features &= ~NETIF_F_UFO;
5677 int __netdev_update_features(struct net_device *dev)
5679 netdev_features_t features;
5684 features = netdev_get_wanted_features(dev);
5686 if (dev->netdev_ops->ndo_fix_features)
5687 features = dev->netdev_ops->ndo_fix_features(dev, features);
5689 /* driver might be less strict about feature dependencies */
5690 features = netdev_fix_features(dev, features);
5692 if (dev->features == features)
5695 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5696 &dev->features, &features);
5698 if (dev->netdev_ops->ndo_set_features)
5699 err = dev->netdev_ops->ndo_set_features(dev, features);
5701 if (unlikely(err < 0)) {
5703 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5704 err, &features, &dev->features);
5709 dev->features = features;
5715 * netdev_update_features - recalculate device features
5716 * @dev: the device to check
5718 * Recalculate dev->features set and send notifications if it
5719 * has changed. Should be called after driver or hardware dependent
5720 * conditions might have changed that influence the features.
5722 void netdev_update_features(struct net_device *dev)
5724 if (__netdev_update_features(dev))
5725 netdev_features_change(dev);
5727 EXPORT_SYMBOL(netdev_update_features);
5730 * netdev_change_features - recalculate device features
5731 * @dev: the device to check
5733 * Recalculate dev->features set and send notifications even
5734 * if they have not changed. Should be called instead of
5735 * netdev_update_features() if also dev->vlan_features might
5736 * have changed to allow the changes to be propagated to stacked
5739 void netdev_change_features(struct net_device *dev)
5741 __netdev_update_features(dev);
5742 netdev_features_change(dev);
5744 EXPORT_SYMBOL(netdev_change_features);
5747 * netif_stacked_transfer_operstate - transfer operstate
5748 * @rootdev: the root or lower level device to transfer state from
5749 * @dev: the device to transfer operstate to
5751 * Transfer operational state from root to device. This is normally
5752 * called when a stacking relationship exists between the root
5753 * device and the device(a leaf device).
5755 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5756 struct net_device *dev)
5758 if (rootdev->operstate == IF_OPER_DORMANT)
5759 netif_dormant_on(dev);
5761 netif_dormant_off(dev);
5763 if (netif_carrier_ok(rootdev)) {
5764 if (!netif_carrier_ok(dev))
5765 netif_carrier_on(dev);
5767 if (netif_carrier_ok(dev))
5768 netif_carrier_off(dev);
5771 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5774 static int netif_alloc_rx_queues(struct net_device *dev)
5776 unsigned int i, count = dev->num_rx_queues;
5777 struct netdev_rx_queue *rx;
5781 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5787 for (i = 0; i < count; i++)
5793 static void netdev_init_one_queue(struct net_device *dev,
5794 struct netdev_queue *queue, void *_unused)
5796 /* Initialize queue lock */
5797 spin_lock_init(&queue->_xmit_lock);
5798 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5799 queue->xmit_lock_owner = -1;
5800 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5803 dql_init(&queue->dql, HZ);
5807 static void netif_free_tx_queues(struct net_device *dev)
5809 if (is_vmalloc_addr(dev->_tx))
5815 static int netif_alloc_netdev_queues(struct net_device *dev)
5817 unsigned int count = dev->num_tx_queues;
5818 struct netdev_queue *tx;
5819 size_t sz = count * sizeof(*tx);
5821 BUG_ON(count < 1 || count > 0xffff);
5823 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5831 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5832 spin_lock_init(&dev->tx_global_lock);
5838 * register_netdevice - register a network device
5839 * @dev: device to register
5841 * Take a completed network device structure and add it to the kernel
5842 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5843 * chain. 0 is returned on success. A negative errno code is returned
5844 * on a failure to set up the device, or if the name is a duplicate.
5846 * Callers must hold the rtnl semaphore. You may want
5847 * register_netdev() instead of this.
5850 * The locking appears insufficient to guarantee two parallel registers
5851 * will not get the same name.
5854 int register_netdevice(struct net_device *dev)
5857 struct net *net = dev_net(dev);
5859 BUG_ON(dev_boot_phase);
5864 /* When net_device's are persistent, this will be fatal. */
5865 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5868 spin_lock_init(&dev->addr_list_lock);
5869 netdev_set_addr_lockdep_class(dev);
5873 ret = dev_get_valid_name(net, dev, dev->name);
5877 /* Init, if this function is available */
5878 if (dev->netdev_ops->ndo_init) {
5879 ret = dev->netdev_ops->ndo_init(dev);
5887 if (((dev->hw_features | dev->features) &
5888 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5889 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5890 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5891 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5898 dev->ifindex = dev_new_index(net);
5899 else if (__dev_get_by_index(net, dev->ifindex))
5902 if (dev->iflink == -1)
5903 dev->iflink = dev->ifindex;
5905 /* Transfer changeable features to wanted_features and enable
5906 * software offloads (GSO and GRO).
5908 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5909 dev->features |= NETIF_F_SOFT_FEATURES;
5910 dev->wanted_features = dev->features & dev->hw_features;
5912 if (!(dev->flags & IFF_LOOPBACK)) {
5913 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5916 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5918 dev->vlan_features |= NETIF_F_HIGHDMA;
5920 /* Make NETIF_F_SG inheritable to tunnel devices.
5922 dev->hw_enc_features |= NETIF_F_SG;
5924 /* Make NETIF_F_SG inheritable to MPLS.
5926 dev->mpls_features |= NETIF_F_SG;
5928 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5929 ret = notifier_to_errno(ret);
5933 ret = netdev_register_kobject(dev);
5936 dev->reg_state = NETREG_REGISTERED;
5938 __netdev_update_features(dev);
5941 * Default initial state at registry is that the
5942 * device is present.
5945 set_bit(__LINK_STATE_PRESENT, &dev->state);
5947 linkwatch_init_dev(dev);
5949 dev_init_scheduler(dev);
5951 list_netdevice(dev);
5952 add_device_randomness(dev->dev_addr, dev->addr_len);
5954 /* If the device has permanent device address, driver should
5955 * set dev_addr and also addr_assign_type should be set to
5956 * NET_ADDR_PERM (default value).
5958 if (dev->addr_assign_type == NET_ADDR_PERM)
5959 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5961 /* Notify protocols, that a new device appeared. */
5962 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5963 ret = notifier_to_errno(ret);
5965 rollback_registered(dev);
5966 dev->reg_state = NETREG_UNREGISTERED;
5969 * Prevent userspace races by waiting until the network
5970 * device is fully setup before sending notifications.
5972 if (!dev->rtnl_link_ops ||
5973 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5974 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5980 if (dev->netdev_ops->ndo_uninit)
5981 dev->netdev_ops->ndo_uninit(dev);
5984 EXPORT_SYMBOL(register_netdevice);
5987 * init_dummy_netdev - init a dummy network device for NAPI
5988 * @dev: device to init
5990 * This takes a network device structure and initialize the minimum
5991 * amount of fields so it can be used to schedule NAPI polls without
5992 * registering a full blown interface. This is to be used by drivers
5993 * that need to tie several hardware interfaces to a single NAPI
5994 * poll scheduler due to HW limitations.
5996 int init_dummy_netdev(struct net_device *dev)
5998 /* Clear everything. Note we don't initialize spinlocks
5999 * are they aren't supposed to be taken by any of the
6000 * NAPI code and this dummy netdev is supposed to be
6001 * only ever used for NAPI polls
6003 memset(dev, 0, sizeof(struct net_device));
6005 /* make sure we BUG if trying to hit standard
6006 * register/unregister code path
6008 dev->reg_state = NETREG_DUMMY;
6010 /* NAPI wants this */
6011 INIT_LIST_HEAD(&dev->napi_list);
6013 /* a dummy interface is started by default */
6014 set_bit(__LINK_STATE_PRESENT, &dev->state);
6015 set_bit(__LINK_STATE_START, &dev->state);
6017 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6018 * because users of this 'device' dont need to change
6024 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6028 * register_netdev - register a network device
6029 * @dev: device to register
6031 * Take a completed network device structure and add it to the kernel
6032 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6033 * chain. 0 is returned on success. A negative errno code is returned
6034 * on a failure to set up the device, or if the name is a duplicate.
6036 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6037 * and expands the device name if you passed a format string to
6040 int register_netdev(struct net_device *dev)
6045 err = register_netdevice(dev);
6049 EXPORT_SYMBOL(register_netdev);
6051 int netdev_refcnt_read(const struct net_device *dev)
6055 for_each_possible_cpu(i)
6056 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6059 EXPORT_SYMBOL(netdev_refcnt_read);
6062 * netdev_wait_allrefs - wait until all references are gone.
6063 * @dev: target net_device
6065 * This is called when unregistering network devices.
6067 * Any protocol or device that holds a reference should register
6068 * for netdevice notification, and cleanup and put back the
6069 * reference if they receive an UNREGISTER event.
6070 * We can get stuck here if buggy protocols don't correctly
6073 static void netdev_wait_allrefs(struct net_device *dev)
6075 unsigned long rebroadcast_time, warning_time;
6078 linkwatch_forget_dev(dev);
6080 rebroadcast_time = warning_time = jiffies;
6081 refcnt = netdev_refcnt_read(dev);
6083 while (refcnt != 0) {
6084 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6087 /* Rebroadcast unregister notification */
6088 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6094 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6095 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6097 /* We must not have linkwatch events
6098 * pending on unregister. If this
6099 * happens, we simply run the queue
6100 * unscheduled, resulting in a noop
6103 linkwatch_run_queue();
6108 rebroadcast_time = jiffies;
6113 refcnt = netdev_refcnt_read(dev);
6115 if (time_after(jiffies, warning_time + 10 * HZ)) {
6116 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6118 warning_time = jiffies;
6127 * register_netdevice(x1);
6128 * register_netdevice(x2);
6130 * unregister_netdevice(y1);
6131 * unregister_netdevice(y2);
6137 * We are invoked by rtnl_unlock().
6138 * This allows us to deal with problems:
6139 * 1) We can delete sysfs objects which invoke hotplug
6140 * without deadlocking with linkwatch via keventd.
6141 * 2) Since we run with the RTNL semaphore not held, we can sleep
6142 * safely in order to wait for the netdev refcnt to drop to zero.
6144 * We must not return until all unregister events added during
6145 * the interval the lock was held have been completed.
6147 void netdev_run_todo(void)
6149 struct list_head list;
6151 /* Snapshot list, allow later requests */
6152 list_replace_init(&net_todo_list, &list);
6157 /* Wait for rcu callbacks to finish before next phase */
6158 if (!list_empty(&list))
6161 while (!list_empty(&list)) {
6162 struct net_device *dev
6163 = list_first_entry(&list, struct net_device, todo_list);
6164 list_del(&dev->todo_list);
6167 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6170 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6171 pr_err("network todo '%s' but state %d\n",
6172 dev->name, dev->reg_state);
6177 dev->reg_state = NETREG_UNREGISTERED;
6179 on_each_cpu(flush_backlog, dev, 1);
6181 netdev_wait_allrefs(dev);
6184 BUG_ON(netdev_refcnt_read(dev));
6185 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6186 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6187 WARN_ON(dev->dn_ptr);
6189 if (dev->destructor)
6190 dev->destructor(dev);
6192 /* Report a network device has been unregistered */
6194 dev_net(dev)->dev_unreg_count--;
6196 wake_up(&netdev_unregistering_wq);
6198 /* Free network device */
6199 kobject_put(&dev->dev.kobj);
6203 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6204 * fields in the same order, with only the type differing.
6206 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6207 const struct net_device_stats *netdev_stats)
6209 #if BITS_PER_LONG == 64
6210 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6211 memcpy(stats64, netdev_stats, sizeof(*stats64));
6213 size_t i, n = sizeof(*stats64) / sizeof(u64);
6214 const unsigned long *src = (const unsigned long *)netdev_stats;
6215 u64 *dst = (u64 *)stats64;
6217 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6218 sizeof(*stats64) / sizeof(u64));
6219 for (i = 0; i < n; i++)
6223 EXPORT_SYMBOL(netdev_stats_to_stats64);
6226 * dev_get_stats - get network device statistics
6227 * @dev: device to get statistics from
6228 * @storage: place to store stats
6230 * Get network statistics from device. Return @storage.
6231 * The device driver may provide its own method by setting
6232 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6233 * otherwise the internal statistics structure is used.
6235 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6236 struct rtnl_link_stats64 *storage)
6238 const struct net_device_ops *ops = dev->netdev_ops;
6240 if (ops->ndo_get_stats64) {
6241 memset(storage, 0, sizeof(*storage));
6242 ops->ndo_get_stats64(dev, storage);
6243 } else if (ops->ndo_get_stats) {
6244 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6246 netdev_stats_to_stats64(storage, &dev->stats);
6248 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6251 EXPORT_SYMBOL(dev_get_stats);
6253 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6255 struct netdev_queue *queue = dev_ingress_queue(dev);
6257 #ifdef CONFIG_NET_CLS_ACT
6260 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6263 netdev_init_one_queue(dev, queue, NULL);
6264 queue->qdisc = &noop_qdisc;
6265 queue->qdisc_sleeping = &noop_qdisc;
6266 rcu_assign_pointer(dev->ingress_queue, queue);
6271 static const struct ethtool_ops default_ethtool_ops;
6273 void netdev_set_default_ethtool_ops(struct net_device *dev,
6274 const struct ethtool_ops *ops)
6276 if (dev->ethtool_ops == &default_ethtool_ops)
6277 dev->ethtool_ops = ops;
6279 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6281 void netdev_freemem(struct net_device *dev)
6283 char *addr = (char *)dev - dev->padded;
6285 if (is_vmalloc_addr(addr))
6292 * alloc_netdev_mqs - allocate network device
6293 * @sizeof_priv: size of private data to allocate space for
6294 * @name: device name format string
6295 * @setup: callback to initialize device
6296 * @txqs: the number of TX subqueues to allocate
6297 * @rxqs: the number of RX subqueues to allocate
6299 * Allocates a struct net_device with private data area for driver use
6300 * and performs basic initialization. Also allocates subqueue structs
6301 * for each queue on the device.
6303 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6304 void (*setup)(struct net_device *),
6305 unsigned int txqs, unsigned int rxqs)
6307 struct net_device *dev;
6309 struct net_device *p;
6311 BUG_ON(strlen(name) >= sizeof(dev->name));
6314 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6320 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6325 alloc_size = sizeof(struct net_device);
6327 /* ensure 32-byte alignment of private area */
6328 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6329 alloc_size += sizeof_priv;
6331 /* ensure 32-byte alignment of whole construct */
6332 alloc_size += NETDEV_ALIGN - 1;
6334 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6336 p = vzalloc(alloc_size);
6340 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6341 dev->padded = (char *)dev - (char *)p;
6343 dev->pcpu_refcnt = alloc_percpu(int);
6344 if (!dev->pcpu_refcnt)
6347 if (dev_addr_init(dev))
6353 dev_net_set(dev, &init_net);
6355 dev->gso_max_size = GSO_MAX_SIZE;
6356 dev->gso_max_segs = GSO_MAX_SEGS;
6358 INIT_LIST_HEAD(&dev->napi_list);
6359 INIT_LIST_HEAD(&dev->unreg_list);
6360 INIT_LIST_HEAD(&dev->close_list);
6361 INIT_LIST_HEAD(&dev->link_watch_list);
6362 INIT_LIST_HEAD(&dev->adj_list.upper);
6363 INIT_LIST_HEAD(&dev->adj_list.lower);
6364 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6365 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6366 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6369 dev->num_tx_queues = txqs;
6370 dev->real_num_tx_queues = txqs;
6371 if (netif_alloc_netdev_queues(dev))
6375 dev->num_rx_queues = rxqs;
6376 dev->real_num_rx_queues = rxqs;
6377 if (netif_alloc_rx_queues(dev))
6381 strcpy(dev->name, name);
6382 dev->group = INIT_NETDEV_GROUP;
6383 if (!dev->ethtool_ops)
6384 dev->ethtool_ops = &default_ethtool_ops;
6392 free_percpu(dev->pcpu_refcnt);
6393 netif_free_tx_queues(dev);
6399 netdev_freemem(dev);
6402 EXPORT_SYMBOL(alloc_netdev_mqs);
6405 * free_netdev - free network device
6408 * This function does the last stage of destroying an allocated device
6409 * interface. The reference to the device object is released.
6410 * If this is the last reference then it will be freed.
6412 void free_netdev(struct net_device *dev)
6414 struct napi_struct *p, *n;
6416 release_net(dev_net(dev));
6418 netif_free_tx_queues(dev);
6423 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6425 /* Flush device addresses */
6426 dev_addr_flush(dev);
6428 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6431 free_percpu(dev->pcpu_refcnt);
6432 dev->pcpu_refcnt = NULL;
6434 /* Compatibility with error handling in drivers */
6435 if (dev->reg_state == NETREG_UNINITIALIZED) {
6436 netdev_freemem(dev);
6440 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6441 dev->reg_state = NETREG_RELEASED;
6443 /* will free via device release */
6444 put_device(&dev->dev);
6446 EXPORT_SYMBOL(free_netdev);
6449 * synchronize_net - Synchronize with packet receive processing
6451 * Wait for packets currently being received to be done.
6452 * Does not block later packets from starting.
6454 void synchronize_net(void)
6457 if (rtnl_is_locked())
6458 synchronize_rcu_expedited();
6462 EXPORT_SYMBOL(synchronize_net);
6465 * unregister_netdevice_queue - remove device from the kernel
6469 * This function shuts down a device interface and removes it
6470 * from the kernel tables.
6471 * If head not NULL, device is queued to be unregistered later.
6473 * Callers must hold the rtnl semaphore. You may want
6474 * unregister_netdev() instead of this.
6477 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6482 list_move_tail(&dev->unreg_list, head);
6484 rollback_registered(dev);
6485 /* Finish processing unregister after unlock */
6489 EXPORT_SYMBOL(unregister_netdevice_queue);
6492 * unregister_netdevice_many - unregister many devices
6493 * @head: list of devices
6495 void unregister_netdevice_many(struct list_head *head)
6497 struct net_device *dev;
6499 if (!list_empty(head)) {
6500 rollback_registered_many(head);
6501 list_for_each_entry(dev, head, unreg_list)
6505 EXPORT_SYMBOL(unregister_netdevice_many);
6508 * unregister_netdev - remove device from the kernel
6511 * This function shuts down a device interface and removes it
6512 * from the kernel tables.
6514 * This is just a wrapper for unregister_netdevice that takes
6515 * the rtnl semaphore. In general you want to use this and not
6516 * unregister_netdevice.
6518 void unregister_netdev(struct net_device *dev)
6521 unregister_netdevice(dev);
6524 EXPORT_SYMBOL(unregister_netdev);
6527 * dev_change_net_namespace - move device to different nethost namespace
6529 * @net: network namespace
6530 * @pat: If not NULL name pattern to try if the current device name
6531 * is already taken in the destination network namespace.
6533 * This function shuts down a device interface and moves it
6534 * to a new network namespace. On success 0 is returned, on
6535 * a failure a netagive errno code is returned.
6537 * Callers must hold the rtnl semaphore.
6540 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6546 /* Don't allow namespace local devices to be moved. */
6548 if (dev->features & NETIF_F_NETNS_LOCAL)
6551 /* Ensure the device has been registrered */
6552 if (dev->reg_state != NETREG_REGISTERED)
6555 /* Get out if there is nothing todo */
6557 if (net_eq(dev_net(dev), net))
6560 /* Pick the destination device name, and ensure
6561 * we can use it in the destination network namespace.
6564 if (__dev_get_by_name(net, dev->name)) {
6565 /* We get here if we can't use the current device name */
6568 if (dev_get_valid_name(net, dev, pat) < 0)
6573 * And now a mini version of register_netdevice unregister_netdevice.
6576 /* If device is running close it first. */
6579 /* And unlink it from device chain */
6581 unlist_netdevice(dev);
6585 /* Shutdown queueing discipline. */
6588 /* Notify protocols, that we are about to destroy
6589 this device. They should clean all the things.
6591 Note that dev->reg_state stays at NETREG_REGISTERED.
6592 This is wanted because this way 8021q and macvlan know
6593 the device is just moving and can keep their slaves up.
6595 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6597 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6598 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6601 * Flush the unicast and multicast chains
6606 /* Send a netdev-removed uevent to the old namespace */
6607 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6609 /* Actually switch the network namespace */
6610 dev_net_set(dev, net);
6612 /* If there is an ifindex conflict assign a new one */
6613 if (__dev_get_by_index(net, dev->ifindex)) {
6614 int iflink = (dev->iflink == dev->ifindex);
6615 dev->ifindex = dev_new_index(net);
6617 dev->iflink = dev->ifindex;
6620 /* Send a netdev-add uevent to the new namespace */
6621 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6623 /* Fixup kobjects */
6624 err = device_rename(&dev->dev, dev->name);
6627 /* Add the device back in the hashes */
6628 list_netdevice(dev);
6630 /* Notify protocols, that a new device appeared. */
6631 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6634 * Prevent userspace races by waiting until the network
6635 * device is fully setup before sending notifications.
6637 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6644 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6646 static int dev_cpu_callback(struct notifier_block *nfb,
6647 unsigned long action,
6650 struct sk_buff **list_skb;
6651 struct sk_buff *skb;
6652 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6653 struct softnet_data *sd, *oldsd;
6655 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6658 local_irq_disable();
6659 cpu = smp_processor_id();
6660 sd = &per_cpu(softnet_data, cpu);
6661 oldsd = &per_cpu(softnet_data, oldcpu);
6663 /* Find end of our completion_queue. */
6664 list_skb = &sd->completion_queue;
6666 list_skb = &(*list_skb)->next;
6667 /* Append completion queue from offline CPU. */
6668 *list_skb = oldsd->completion_queue;
6669 oldsd->completion_queue = NULL;
6671 /* Append output queue from offline CPU. */
6672 if (oldsd->output_queue) {
6673 *sd->output_queue_tailp = oldsd->output_queue;
6674 sd->output_queue_tailp = oldsd->output_queue_tailp;
6675 oldsd->output_queue = NULL;
6676 oldsd->output_queue_tailp = &oldsd->output_queue;
6678 /* Append NAPI poll list from offline CPU. */
6679 if (!list_empty(&oldsd->poll_list)) {
6680 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6681 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6684 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6687 /* Process offline CPU's input_pkt_queue */
6688 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6689 netif_rx_internal(skb);
6690 input_queue_head_incr(oldsd);
6692 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6693 netif_rx_internal(skb);
6694 input_queue_head_incr(oldsd);
6702 * netdev_increment_features - increment feature set by one
6703 * @all: current feature set
6704 * @one: new feature set
6705 * @mask: mask feature set
6707 * Computes a new feature set after adding a device with feature set
6708 * @one to the master device with current feature set @all. Will not
6709 * enable anything that is off in @mask. Returns the new feature set.
6711 netdev_features_t netdev_increment_features(netdev_features_t all,
6712 netdev_features_t one, netdev_features_t mask)
6714 if (mask & NETIF_F_GEN_CSUM)
6715 mask |= NETIF_F_ALL_CSUM;
6716 mask |= NETIF_F_VLAN_CHALLENGED;
6718 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6719 all &= one | ~NETIF_F_ALL_FOR_ALL;
6721 /* If one device supports hw checksumming, set for all. */
6722 if (all & NETIF_F_GEN_CSUM)
6723 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6727 EXPORT_SYMBOL(netdev_increment_features);
6729 static struct hlist_head * __net_init netdev_create_hash(void)
6732 struct hlist_head *hash;
6734 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6736 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6737 INIT_HLIST_HEAD(&hash[i]);
6742 /* Initialize per network namespace state */
6743 static int __net_init netdev_init(struct net *net)
6745 if (net != &init_net)
6746 INIT_LIST_HEAD(&net->dev_base_head);
6748 net->dev_name_head = netdev_create_hash();
6749 if (net->dev_name_head == NULL)
6752 net->dev_index_head = netdev_create_hash();
6753 if (net->dev_index_head == NULL)
6759 kfree(net->dev_name_head);
6765 * netdev_drivername - network driver for the device
6766 * @dev: network device
6768 * Determine network driver for device.
6770 const char *netdev_drivername(const struct net_device *dev)
6772 const struct device_driver *driver;
6773 const struct device *parent;
6774 const char *empty = "";
6776 parent = dev->dev.parent;
6780 driver = parent->driver;
6781 if (driver && driver->name)
6782 return driver->name;
6786 static int __netdev_printk(const char *level, const struct net_device *dev,
6787 struct va_format *vaf)
6791 if (dev && dev->dev.parent) {
6792 r = dev_printk_emit(level[1] - '0',
6795 dev_driver_string(dev->dev.parent),
6796 dev_name(dev->dev.parent),
6797 netdev_name(dev), vaf);
6799 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6801 r = printk("%s(NULL net_device): %pV", level, vaf);
6807 int netdev_printk(const char *level, const struct net_device *dev,
6808 const char *format, ...)
6810 struct va_format vaf;
6814 va_start(args, format);
6819 r = __netdev_printk(level, dev, &vaf);
6825 EXPORT_SYMBOL(netdev_printk);
6827 #define define_netdev_printk_level(func, level) \
6828 int func(const struct net_device *dev, const char *fmt, ...) \
6831 struct va_format vaf; \
6834 va_start(args, fmt); \
6839 r = __netdev_printk(level, dev, &vaf); \
6845 EXPORT_SYMBOL(func);
6847 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6848 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6849 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6850 define_netdev_printk_level(netdev_err, KERN_ERR);
6851 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6852 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6853 define_netdev_printk_level(netdev_info, KERN_INFO);
6855 static void __net_exit netdev_exit(struct net *net)
6857 kfree(net->dev_name_head);
6858 kfree(net->dev_index_head);
6861 static struct pernet_operations __net_initdata netdev_net_ops = {
6862 .init = netdev_init,
6863 .exit = netdev_exit,
6866 static void __net_exit default_device_exit(struct net *net)
6868 struct net_device *dev, *aux;
6870 * Push all migratable network devices back to the
6871 * initial network namespace
6874 for_each_netdev_safe(net, dev, aux) {
6876 char fb_name[IFNAMSIZ];
6878 /* Ignore unmoveable devices (i.e. loopback) */
6879 if (dev->features & NETIF_F_NETNS_LOCAL)
6882 /* Leave virtual devices for the generic cleanup */
6883 if (dev->rtnl_link_ops)
6886 /* Push remaining network devices to init_net */
6887 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6888 err = dev_change_net_namespace(dev, &init_net, fb_name);
6890 pr_emerg("%s: failed to move %s to init_net: %d\n",
6891 __func__, dev->name, err);
6898 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6900 /* Return with the rtnl_lock held when there are no network
6901 * devices unregistering in any network namespace in net_list.
6908 prepare_to_wait(&netdev_unregistering_wq, &wait,
6909 TASK_UNINTERRUPTIBLE);
6910 unregistering = false;
6912 list_for_each_entry(net, net_list, exit_list) {
6913 if (net->dev_unreg_count > 0) {
6914 unregistering = true;
6923 finish_wait(&netdev_unregistering_wq, &wait);
6926 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6928 /* At exit all network devices most be removed from a network
6929 * namespace. Do this in the reverse order of registration.
6930 * Do this across as many network namespaces as possible to
6931 * improve batching efficiency.
6933 struct net_device *dev;
6935 LIST_HEAD(dev_kill_list);
6937 /* To prevent network device cleanup code from dereferencing
6938 * loopback devices or network devices that have been freed
6939 * wait here for all pending unregistrations to complete,
6940 * before unregistring the loopback device and allowing the
6941 * network namespace be freed.
6943 * The netdev todo list containing all network devices
6944 * unregistrations that happen in default_device_exit_batch
6945 * will run in the rtnl_unlock() at the end of
6946 * default_device_exit_batch.
6948 rtnl_lock_unregistering(net_list);
6949 list_for_each_entry(net, net_list, exit_list) {
6950 for_each_netdev_reverse(net, dev) {
6951 if (dev->rtnl_link_ops)
6952 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6954 unregister_netdevice_queue(dev, &dev_kill_list);
6957 unregister_netdevice_many(&dev_kill_list);
6958 list_del(&dev_kill_list);
6962 static struct pernet_operations __net_initdata default_device_ops = {
6963 .exit = default_device_exit,
6964 .exit_batch = default_device_exit_batch,
6968 * Initialize the DEV module. At boot time this walks the device list and
6969 * unhooks any devices that fail to initialise (normally hardware not
6970 * present) and leaves us with a valid list of present and active devices.
6975 * This is called single threaded during boot, so no need
6976 * to take the rtnl semaphore.
6978 static int __init net_dev_init(void)
6980 int i, rc = -ENOMEM;
6982 BUG_ON(!dev_boot_phase);
6984 if (dev_proc_init())
6987 if (netdev_kobject_init())
6990 INIT_LIST_HEAD(&ptype_all);
6991 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6992 INIT_LIST_HEAD(&ptype_base[i]);
6994 INIT_LIST_HEAD(&offload_base);
6996 if (register_pernet_subsys(&netdev_net_ops))
7000 * Initialise the packet receive queues.
7003 for_each_possible_cpu(i) {
7004 struct softnet_data *sd = &per_cpu(softnet_data, i);
7006 skb_queue_head_init(&sd->input_pkt_queue);
7007 skb_queue_head_init(&sd->process_queue);
7008 INIT_LIST_HEAD(&sd->poll_list);
7009 sd->output_queue_tailp = &sd->output_queue;
7011 sd->csd.func = rps_trigger_softirq;
7016 sd->backlog.poll = process_backlog;
7017 sd->backlog.weight = weight_p;
7022 /* The loopback device is special if any other network devices
7023 * is present in a network namespace the loopback device must
7024 * be present. Since we now dynamically allocate and free the
7025 * loopback device ensure this invariant is maintained by
7026 * keeping the loopback device as the first device on the
7027 * list of network devices. Ensuring the loopback devices
7028 * is the first device that appears and the last network device
7031 if (register_pernet_device(&loopback_net_ops))
7034 if (register_pernet_device(&default_device_ops))
7037 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7038 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7040 hotcpu_notifier(dev_cpu_callback, 0);
7047 subsys_initcall(net_dev_init);