dev.c 216.1 KB
Newer Older
L
Linus Torvalds 已提交
1
/*
2
 *      NET3    Protocol independent device support routines.
L
Linus Torvalds 已提交
3 4 5 6 7 8 9
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	Derived from the non IP parts of dev.c 1.0.19
10
 *              Authors:	Ross Biro
L
Linus Torvalds 已提交
11 12 13 14 15 16 17 18 19 20 21 22 23
 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
 *
 *	Additional Authors:
 *		Florian la Roche <rzsfl@rz.uni-sb.de>
 *		Alan Cox <gw4pts@gw4pts.ampr.org>
 *		David Hinds <dahinds@users.sourceforge.net>
 *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 *		Adam Sulmicki <adam@cfar.umd.edu>
 *              Pekka Riikonen <priikone@poesidon.pspt.fi>
 *
 *	Changes:
 *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
24 25 26
 *                                      to 2 if register_netdev gets called
 *                                      before net_dev_init & also removed a
 *                                      few lines of code in the process.
L
Linus Torvalds 已提交
27 28 29 30 31 32 33 34 35 36 37 38
 *		Alan Cox	:	device private ioctl copies fields back.
 *		Alan Cox	:	Transmit queue code does relevant
 *					stunts to keep the queue safe.
 *		Alan Cox	:	Fixed double lock.
 *		Alan Cox	:	Fixed promisc NULL pointer trap
 *		????????	:	Support the full private ioctl range
 *		Alan Cox	:	Moved ioctl permission check into
 *					drivers
 *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
 *		Alan Cox	:	100 backlog just doesn't cut it when
 *					you start doing multicast video 8)
 *		Alan Cox	:	Rewrote net_bh and list manager.
39
 *              Alan Cox        :       Fix ETH_P_ALL echoback lengths.
L
Linus Torvalds 已提交
40 41 42 43 44 45 46 47 48
 *		Alan Cox	:	Took out transmit every packet pass
 *					Saved a few bytes in the ioctl handler
 *		Alan Cox	:	Network driver sets packet type before
 *					calling netif_rx. Saves a function
 *					call a packet.
 *		Alan Cox	:	Hashed net_bh()
 *		Richard Kooijman:	Timestamp fixes.
 *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
 *		Alan Cox	:	Device lock protection.
49
 *              Alan Cox        :       Fixed nasty side effect of device close
L
Linus Torvalds 已提交
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
 *					changes.
 *		Rudi Cilibrasi	:	Pass the right thing to
 *					set_mac_address()
 *		Dave Miller	:	32bit quantity for the device lock to
 *					make it work out on a Sparc.
 *		Bjorn Ekwall	:	Added KERNELD hack.
 *		Alan Cox	:	Cleaned up the backlog initialise.
 *		Craig Metz	:	SIOCGIFCONF fix if space for under
 *					1 device.
 *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
 *					is no device open function.
 *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
 *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
 *		Cyrus Durgin	:	Cleaned for KMOD
 *		Adam Sulmicki   :	Bug Fix : Network Device Unload
 *					A network device unload needs to purge
 *					the backlog queue.
 *	Paul Rusty Russell	:	SIOCSIFNAME
 *              Pekka Riikonen  :	Netdev boot-time settings code
 *              Andrew Morton   :       Make unregister_netdevice wait
70 71
 *                                      indefinitely on dev->refcnt
 *              J Hadi Salim    :       - Backlog queue sampling
L
Linus Torvalds 已提交
72 73 74
 *				        - netif_rx() feedback
 */

75
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
76
#include <linux/bitops.h>
77
#include <linux/capability.h>
L
Linus Torvalds 已提交
78 79 80
#include <linux/cpu.h>
#include <linux/types.h>
#include <linux/kernel.h>
81
#include <linux/hash.h>
82
#include <linux/slab.h>
L
Linus Torvalds 已提交
83
#include <linux/sched.h>
84
#include <linux/sched/mm.h>
A
Arjan van de Ven 已提交
85
#include <linux/mutex.h>
L
Linus Torvalds 已提交
86 87 88 89 90 91 92 93 94
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
95
#include <linux/ethtool.h>
L
Linus Torvalds 已提交
96 97
#include <linux/notifier.h>
#include <linux/skbuff.h>
98
#include <linux/bpf.h>
D
David S. Miller 已提交
99
#include <linux/bpf_trace.h>
100
#include <net/net_namespace.h>
L
Linus Torvalds 已提交
101
#include <net/sock.h>
E
Eric Dumazet 已提交
102
#include <net/busy_poll.h>
L
Linus Torvalds 已提交
103 104 105
#include <linux/rtnetlink.h>
#include <linux/stat.h>
#include <net/dst.h>
106
#include <net/dst_metadata.h>
L
Linus Torvalds 已提交
107
#include <net/pkt_sched.h>
108
#include <net/pkt_cls.h>
L
Linus Torvalds 已提交
109
#include <net/checksum.h>
110
#include <net/xfrm.h>
L
Linus Torvalds 已提交
111 112 113 114 115 116 117 118
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netpoll.h>
#include <linux/rcupdate.h>
#include <linux/delay.h>
#include <net/iw_handler.h>
#include <asm/current.h>
S
Steve Grubb 已提交
119
#include <linux/audit.h>
120
#include <linux/dmaengine.h>
121
#include <linux/err.h>
122
#include <linux/ctype.h>
123
#include <linux/if_arp.h>
124
#include <linux/if_vlan.h>
125
#include <linux/ip.h>
126
#include <net/ip.h>
127
#include <net/mpls.h>
128 129
#include <linux/ipv6.h>
#include <linux/in.h>
D
David S. Miller 已提交
130 131
#include <linux/jhash.h>
#include <linux/random.h>
132
#include <trace/events/napi.h>
133
#include <trace/events/net.h>
134
#include <trace/events/skb.h>
135
#include <linux/pci.h>
136
#include <linux/inetdevice.h>
137
#include <linux/cpu_rmap.h>
138
#include <linux/static_key.h>
E
Eliezer Tamir 已提交
139
#include <linux/hashtable.h>
140
#include <linux/vmalloc.h>
141
#include <linux/if_macvlan.h>
142
#include <linux/errqueue.h>
143
#include <linux/hrtimer.h>
144
#include <linux/netfilter_ingress.h>
145
#include <linux/crash_dump.h>
146
#include <linux/sctp.h>
L
Linus Torvalds 已提交
147

148 149
#include "net-sysfs.h"

150 151 152
/* Instead of increasing this, you should create a hash table. */
#define MAX_GRO_SKBS 8

H
Herbert Xu 已提交
153 154 155
/* This should be increased if a protocol with a bigger head is added. */
#define GRO_MAX_HEAD (MAX_HEADER + 128)

L
Linus Torvalds 已提交
156
static DEFINE_SPINLOCK(ptype_lock);
157
static DEFINE_SPINLOCK(offload_lock);
158 159
struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
struct list_head ptype_all __read_mostly;	/* Taps */
160
static struct list_head offload_base __read_mostly;
L
Linus Torvalds 已提交
161

162
static int netif_rx_internal(struct sk_buff *skb);
163 164 165
static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info);
166
static struct napi_struct *napi_by_id(unsigned int napi_id);
167

L
Linus Torvalds 已提交
168
/*
169
 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
L
Linus Torvalds 已提交
170 171
 * semaphore.
 *
172
 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
L
Linus Torvalds 已提交
173 174
 *
 * Writers must hold the rtnl semaphore while they loop through the
175
 * dev_base_head list, and hold dev_base_lock for writing when they do the
L
Linus Torvalds 已提交
176 177 178 179 180 181 182 183 184 185 186 187 188 189
 * actual updates.  This allows pure readers to access the list even
 * while a writer is preparing to update it.
 *
 * To put it another way, dev_base_lock is held for writing only to
 * protect against pure readers; the rtnl semaphore provides the
 * protection against other writers.
 *
 * See, for example usages, register_netdevice() and
 * unregister_netdevice(), which must be called with the rtnl
 * semaphore held.
 */
DEFINE_RWLOCK(dev_base_lock);
EXPORT_SYMBOL(dev_base_lock);

E
Eliezer Tamir 已提交
190 191 192
/* protects napi_hash addition/deletion and napi_gen_id */
static DEFINE_SPINLOCK(napi_hash_lock);

193
static unsigned int napi_gen_id = NR_CPUS;
194
static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
E
Eliezer Tamir 已提交
195

196
static seqcount_t devnet_rename_seq;
197

198 199
static inline void dev_base_seq_inc(struct net *net)
{
200 201
	while (++net->dev_base_seq == 0)
		;
202 203
}

204
static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
L
Linus Torvalds 已提交
205
{
206
	unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ));
207

208
	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
L
Linus Torvalds 已提交
209 210
}

211
static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
L
Linus Torvalds 已提交
212
{
213
	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
L
Linus Torvalds 已提交
214 215
}

E
Eric Dumazet 已提交
216
static inline void rps_lock(struct softnet_data *sd)
217 218
{
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
219
	spin_lock(&sd->input_pkt_queue.lock);
220 221 222
#endif
}

E
Eric Dumazet 已提交
223
static inline void rps_unlock(struct softnet_data *sd)
224 225
{
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
226
	spin_unlock(&sd->input_pkt_queue.lock);
227 228 229
#endif
}

230
/* Device list insertion */
231
static void list_netdevice(struct net_device *dev)
232
{
233
	struct net *net = dev_net(dev);
234 235 236 237

	ASSERT_RTNL();

	write_lock_bh(&dev_base_lock);
238
	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
239
	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
240 241
	hlist_add_head_rcu(&dev->index_hlist,
			   dev_index_hash(net, dev->ifindex));
242
	write_unlock_bh(&dev_base_lock);
243 244

	dev_base_seq_inc(net);
245 246
}

247 248 249
/* Device list removal
 * caller must respect a RCU grace period before freeing/reusing dev
 */
250 251 252 253 254 255
static void unlist_netdevice(struct net_device *dev)
{
	ASSERT_RTNL();

	/* Unlink dev from the device chain */
	write_lock_bh(&dev_base_lock);
256
	list_del_rcu(&dev->dev_list);
257
	hlist_del_rcu(&dev->name_hlist);
258
	hlist_del_rcu(&dev->index_hlist);
259
	write_unlock_bh(&dev_base_lock);
260 261

	dev_base_seq_inc(dev_net(dev));
262 263
}

L
Linus Torvalds 已提交
264 265 266 267
/*
 *	Our notifier list
 */

268
static RAW_NOTIFIER_HEAD(netdev_chain);
L
Linus Torvalds 已提交
269 270 271 272 273

/*
 *	Device drivers call our routines to queue packets here. We empty the
 *	queue in the local softnet handler.
 */
274

275
DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
E
Eric Dumazet 已提交
276
EXPORT_PER_CPU_SYMBOL(softnet_data);
L
Linus Torvalds 已提交
277

278
#ifdef CONFIG_LOCKDEP
279
/*
280
 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
281 282
 * according to dev->type
 */
283 284
static const unsigned short netdev_lock_type[] = {
	 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
285 286 287 288 289 290 291 292 293 294 295
	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
296 297 298
	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
	 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
299

300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315
static const char *const netdev_lock_name[] = {
	"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
	"_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
	"_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
	"_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
	"_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
	"_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
	"_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
	"_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
	"_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
	"_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
	"_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
	"_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
	"_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
	"_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
	"_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
316 317

static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
318
static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
319 320 321 322 323 324 325 326 327 328 329 330

static inline unsigned short netdev_lock_pos(unsigned short dev_type)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
		if (netdev_lock_type[i] == dev_type)
			return i;
	/* the last key is used by default */
	return ARRAY_SIZE(netdev_lock_type) - 1;
}

331 332
static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
						 unsigned short dev_type)
333 334 335 336 337 338 339
{
	int i;

	i = netdev_lock_pos(dev_type);
	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
				   netdev_lock_name[i]);
}
340 341 342 343 344 345 346 347 348 349

static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
{
	int i;

	i = netdev_lock_pos(dev->type);
	lockdep_set_class_and_name(&dev->addr_list_lock,
				   &netdev_addr_lock_key[i],
				   netdev_lock_name[i]);
}
350
#else
351 352 353 354 355
static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
						 unsigned short dev_type)
{
}
static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
356 357 358
{
}
#endif
L
Linus Torvalds 已提交
359 360

/*******************************************************************************
361 362 363 364
 *
 *		Protocol management and registration routines
 *
 *******************************************************************************/
L
Linus Torvalds 已提交
365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382


/*
 *	Add a protocol ID to the list. Now that the input handler is
 *	smarter we can dispense with all the messy stuff that used to be
 *	here.
 *
 *	BEWARE!!! Protocol handlers, mangling input packets,
 *	MUST BE last in hash buckets and checking protocol handlers
 *	MUST start from promiscuous ptype_all chain in net_bh.
 *	It is true now, do not change it.
 *	Explanation follows: if protocol handler, mangling packet, will
 *	be the first on list, it is not able to sense, that packet
 *	is cloned and should be copied-on-write, so that it will
 *	change it and subsequent readers will get broken packet.
 *							--ANK (980803)
 */

383 384 385
static inline struct list_head *ptype_head(const struct packet_type *pt)
{
	if (pt->type == htons(ETH_P_ALL))
386
		return pt->dev ? &pt->dev->ptype_all : &ptype_all;
387
	else
388 389
		return pt->dev ? &pt->dev->ptype_specific :
				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
390 391
}

L
Linus Torvalds 已提交
392 393 394 395 396 397 398 399
/**
 *	dev_add_pack - add packet handler
 *	@pt: packet type declaration
 *
 *	Add a protocol handler to the networking stack. The passed &packet_type
 *	is linked into kernel lists and may not be freed until it has been
 *	removed from the kernel lists.
 *
400
 *	This call does not sleep therefore it can not
L
Linus Torvalds 已提交
401 402 403 404 405 406
 *	guarantee all CPU's that are in middle of receiving packets
 *	will see the new packet type (until the next received packet).
 */

void dev_add_pack(struct packet_type *pt)
{
407
	struct list_head *head = ptype_head(pt);
L
Linus Torvalds 已提交
408

409 410 411
	spin_lock(&ptype_lock);
	list_add_rcu(&pt->list, head);
	spin_unlock(&ptype_lock);
L
Linus Torvalds 已提交
412
}
E
Eric Dumazet 已提交
413
EXPORT_SYMBOL(dev_add_pack);
L
Linus Torvalds 已提交
414 415 416 417 418 419 420 421

/**
 *	__dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
422
 *	returns.
L
Linus Torvalds 已提交
423 424 425 426 427 428 429
 *
 *      The packet type might still be in use by receivers
 *	and must not be freed until after all the CPU's have gone
 *	through a quiescent state.
 */
void __dev_remove_pack(struct packet_type *pt)
{
430
	struct list_head *head = ptype_head(pt);
L
Linus Torvalds 已提交
431 432
	struct packet_type *pt1;

433
	spin_lock(&ptype_lock);
L
Linus Torvalds 已提交
434 435 436 437 438 439 440 441

	list_for_each_entry(pt1, head, list) {
		if (pt == pt1) {
			list_del_rcu(&pt->list);
			goto out;
		}
	}

442
	pr_warn("dev_remove_pack: %p not found\n", pt);
L
Linus Torvalds 已提交
443
out:
444
	spin_unlock(&ptype_lock);
L
Linus Torvalds 已提交
445
}
E
Eric Dumazet 已提交
446 447
EXPORT_SYMBOL(__dev_remove_pack);

L
Linus Torvalds 已提交
448 449 450 451 452 453 454 455 456 457 458 459 460 461 462
/**
 *	dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
 *	returns.
 *
 *	This call sleeps to guarantee that no CPU is looking at the packet
 *	type after return.
 */
void dev_remove_pack(struct packet_type *pt)
{
	__dev_remove_pack(pt);
463

L
Linus Torvalds 已提交
464 465
	synchronize_net();
}
E
Eric Dumazet 已提交
466
EXPORT_SYMBOL(dev_remove_pack);
L
Linus Torvalds 已提交
467

468 469 470 471 472 473 474 475 476 477 478 479 480 481 482

/**
 *	dev_add_offload - register offload handlers
 *	@po: protocol offload declaration
 *
 *	Add protocol offload handlers to the networking stack. The passed
 *	&proto_offload is linked into kernel lists and may not be freed until
 *	it has been removed from the kernel lists.
 *
 *	This call does not sleep therefore it can not
 *	guarantee all CPU's that are in middle of receiving packets
 *	will see the new offload handlers (until the next received packet).
 */
void dev_add_offload(struct packet_offload *po)
{
483
	struct packet_offload *elem;
484 485

	spin_lock(&offload_lock);
486 487 488 489 490
	list_for_each_entry(elem, &offload_base, list) {
		if (po->priority < elem->priority)
			break;
	}
	list_add_rcu(&po->list, elem->list.prev);
491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507
	spin_unlock(&offload_lock);
}
EXPORT_SYMBOL(dev_add_offload);

/**
 *	__dev_remove_offload	 - remove offload handler
 *	@po: packet offload declaration
 *
 *	Remove a protocol offload handler that was previously added to the
 *	kernel offload handlers by dev_add_offload(). The passed &offload_type
 *	is removed from the kernel lists and can be freed or reused once this
 *	function returns.
 *
 *      The packet type might still be in use by receivers
 *	and must not be freed until after all the CPU's have gone
 *	through a quiescent state.
 */
S
stephen hemminger 已提交
508
static void __dev_remove_offload(struct packet_offload *po)
509 510 511 512
{
	struct list_head *head = &offload_base;
	struct packet_offload *po1;

513
	spin_lock(&offload_lock);
514 515 516 517 518 519 520 521 522 523

	list_for_each_entry(po1, head, list) {
		if (po == po1) {
			list_del_rcu(&po->list);
			goto out;
		}
	}

	pr_warn("dev_remove_offload: %p not found\n", po);
out:
524
	spin_unlock(&offload_lock);
525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546
}

/**
 *	dev_remove_offload	 - remove packet offload handler
 *	@po: packet offload declaration
 *
 *	Remove a packet offload handler that was previously added to the kernel
 *	offload handlers by dev_add_offload(). The passed &offload_type is
 *	removed from the kernel lists and can be freed or reused once this
 *	function returns.
 *
 *	This call sleeps to guarantee that no CPU is looking at the packet
 *	type after return.
 */
void dev_remove_offload(struct packet_offload *po)
{
	__dev_remove_offload(po);

	synchronize_net();
}
EXPORT_SYMBOL(dev_remove_offload);

L
Linus Torvalds 已提交
547
/******************************************************************************
548 549 550 551
 *
 *		      Device Boot-time Settings Routines
 *
 ******************************************************************************/
L
Linus Torvalds 已提交
552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573

/* Boot time configuration table */
static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];

/**
 *	netdev_boot_setup_add	- add new setup entry
 *	@name: name of the device
 *	@map: configured settings for the device
 *
 *	Adds new setup entry to the dev_boot_setup list.  The function
 *	returns 0 on error and 1 on success.  This is a generic routine to
 *	all netdevices.
 */
static int netdev_boot_setup_add(char *name, struct ifmap *map)
{
	struct netdev_boot_setup *s;
	int i;

	s = dev_boot_setup;
	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
			memset(s[i].name, 0, sizeof(s[i].name));
574
			strlcpy(s[i].name, name, IFNAMSIZ);
L
Linus Torvalds 已提交
575 576 577 578 579 580 581 582 583
			memcpy(&s[i].map, map, sizeof(s[i].map));
			break;
		}
	}

	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
}

/**
584 585
 * netdev_boot_setup_check	- check boot time settings
 * @dev: the netdevice
L
Linus Torvalds 已提交
586
 *
587 588 589 590
 * Check boot time settings for the device.
 * The found settings are set for the device to be used
 * later in the device probing.
 * Returns 0 if no settings found, 1 if they are.
L
Linus Torvalds 已提交
591 592 593 594 595 596 597 598
 */
int netdev_boot_setup_check(struct net_device *dev)
{
	struct netdev_boot_setup *s = dev_boot_setup;
	int i;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
599
		    !strcmp(dev->name, s[i].name)) {
600 601 602 603
			dev->irq = s[i].map.irq;
			dev->base_addr = s[i].map.base_addr;
			dev->mem_start = s[i].map.mem_start;
			dev->mem_end = s[i].map.mem_end;
L
Linus Torvalds 已提交
604 605 606 607 608
			return 1;
		}
	}
	return 0;
}
E
Eric Dumazet 已提交
609
EXPORT_SYMBOL(netdev_boot_setup_check);
L
Linus Torvalds 已提交
610 611 612


/**
613 614 615 616 617 618 619 620
 * netdev_boot_base	- get address from boot time settings
 * @prefix: prefix for network device
 * @unit: id for network device
 *
 * Check boot time settings for the base address of device.
 * The found settings are set for the device to be used
 * later in the device probing.
 * Returns 0 if no settings found.
L
Linus Torvalds 已提交
621 622 623 624 625 626 627 628 629 630 631 632 633
 */
unsigned long netdev_boot_base(const char *prefix, int unit)
{
	const struct netdev_boot_setup *s = dev_boot_setup;
	char name[IFNAMSIZ];
	int i;

	sprintf(name, "%s%d", prefix, unit);

	/*
	 * If device already registered then return base of 1
	 * to indicate not to probe for this interface
	 */
634
	if (__dev_get_by_name(&init_net, name))
L
Linus Torvalds 已提交
635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672
		return 1;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
		if (!strcmp(name, s[i].name))
			return s[i].map.base_addr;
	return 0;
}

/*
 * Saves at boot time configured settings for any netdevice.
 */
int __init netdev_boot_setup(char *str)
{
	int ints[5];
	struct ifmap map;

	str = get_options(str, ARRAY_SIZE(ints), ints);
	if (!str || !*str)
		return 0;

	/* Save settings */
	memset(&map, 0, sizeof(map));
	if (ints[0] > 0)
		map.irq = ints[1];
	if (ints[0] > 1)
		map.base_addr = ints[2];
	if (ints[0] > 2)
		map.mem_start = ints[3];
	if (ints[0] > 3)
		map.mem_end = ints[4];

	/* Add new entry to the list */
	return netdev_boot_setup_add(str, &map);
}

__setup("netdev=", netdev_boot_setup);

/*******************************************************************************
673 674 675 676
 *
 *			    Device Interface Subroutines
 *
 *******************************************************************************/
L
Linus Torvalds 已提交
677

678 679 680 681 682 683 684 685 686 687 688 689 690
/**
 *	dev_get_iflink	- get 'iflink' value of a interface
 *	@dev: targeted interface
 *
 *	Indicates the ifindex the interface is linked to.
 *	Physical interfaces have the same 'ifindex' and 'iflink' values.
 */

int dev_get_iflink(const struct net_device *dev)
{
	if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
		return dev->netdev_ops->ndo_get_iflink(dev);

691
	return dev->ifindex;
692 693 694
}
EXPORT_SYMBOL(dev_get_iflink);

695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
/**
 *	dev_fill_metadata_dst - Retrieve tunnel egress information.
 *	@dev: targeted interface
 *	@skb: The packet.
 *
 *	For better visibility of tunnel traffic OVS needs to retrieve
 *	egress tunnel information for a packet. Following API allows
 *	user to get this info.
 */
int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
{
	struct ip_tunnel_info *info;

	if (!dev->netdev_ops  || !dev->netdev_ops->ndo_fill_metadata_dst)
		return -EINVAL;

	info = skb_tunnel_info_unclone(skb);
	if (!info)
		return -ENOMEM;
	if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
		return -EINVAL;

	return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
}
EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);

L
Linus Torvalds 已提交
721 722
/**
 *	__dev_get_by_name	- find a device by its name
723
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
724 725 726 727 728 729 730 731 732
 *	@name: name to find
 *
 *	Find an interface by name. Must be called under RTNL semaphore
 *	or @dev_base_lock. If the name is found a pointer to the device
 *	is returned. If the name is not found then %NULL is returned. The
 *	reference counters are not incremented so the caller must be
 *	careful with locks.
 */

733
struct net_device *__dev_get_by_name(struct net *net, const char *name)
L
Linus Torvalds 已提交
734
{
E
Eric Dumazet 已提交
735 736
	struct net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);
L
Linus Torvalds 已提交
737

738
	hlist_for_each_entry(dev, head, name_hlist)
L
Linus Torvalds 已提交
739 740
		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;
E
Eric Dumazet 已提交
741

L
Linus Torvalds 已提交
742 743
	return NULL;
}
E
Eric Dumazet 已提交
744
EXPORT_SYMBOL(__dev_get_by_name);
L
Linus Torvalds 已提交
745

746
/**
747 748 749 750 751 752 753 754 755
 * dev_get_by_name_rcu	- find a device by its name
 * @net: the applicable net namespace
 * @name: name to find
 *
 * Find an interface by name.
 * If the name is found a pointer to the device is returned.
 * If the name is not found then %NULL is returned.
 * The reference counters are not incremented so the caller must be
 * careful with locks. The caller must hold RCU lock.
756 757 758 759 760 761 762
 */

struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
{
	struct net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);

763
	hlist_for_each_entry_rcu(dev, head, name_hlist)
764 765 766 767 768 769 770
		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_name_rcu);

L
Linus Torvalds 已提交
771 772
/**
 *	dev_get_by_name		- find a device by its name
773
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
774 775 776 777 778 779 780 781 782
 *	@name: name to find
 *
 *	Find an interface by name. This can be called from any
 *	context and does its own locking. The returned handle has
 *	the usage count incremented and the caller must use dev_put() to
 *	release it when it is no longer needed. %NULL is returned if no
 *	matching device is found.
 */

783
struct net_device *dev_get_by_name(struct net *net, const char *name)
L
Linus Torvalds 已提交
784 785 786
{
	struct net_device *dev;

787 788
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
L
Linus Torvalds 已提交
789 790
	if (dev)
		dev_hold(dev);
791
	rcu_read_unlock();
L
Linus Torvalds 已提交
792 793
	return dev;
}
E
Eric Dumazet 已提交
794
EXPORT_SYMBOL(dev_get_by_name);
L
Linus Torvalds 已提交
795 796 797

/**
 *	__dev_get_by_index - find a device by its ifindex
798
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
799 800 801 802 803 804 805 806 807
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not
 *	had its reference counter increased so the caller must be careful
 *	about locking. The caller must hold either the RTNL semaphore
 *	or @dev_base_lock.
 */

808
struct net_device *__dev_get_by_index(struct net *net, int ifindex)
L
Linus Torvalds 已提交
809
{
E
Eric Dumazet 已提交
810 811
	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);
L
Linus Torvalds 已提交
812

813
	hlist_for_each_entry(dev, head, index_hlist)
L
Linus Torvalds 已提交
814 815
		if (dev->ifindex == ifindex)
			return dev;
E
Eric Dumazet 已提交
816

L
Linus Torvalds 已提交
817 818
	return NULL;
}
E
Eric Dumazet 已提交
819
EXPORT_SYMBOL(__dev_get_by_index);
L
Linus Torvalds 已提交
820

821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836
/**
 *	dev_get_by_index_rcu - find a device by its ifindex
 *	@net: the applicable net namespace
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not
 *	had its reference counter increased so the caller must be careful
 *	about locking. The caller must hold RCU lock.
 */

struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
{
	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);

837
	hlist_for_each_entry_rcu(dev, head, index_hlist)
838 839 840 841 842 843 844
		if (dev->ifindex == ifindex)
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_index_rcu);

L
Linus Torvalds 已提交
845 846 847

/**
 *	dev_get_by_index - find a device by its ifindex
848
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
849 850 851 852 853 854 855 856
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns NULL if the device
 *	is not found or a pointer to the device. The device returned has
 *	had a reference added and the pointer is safe until the user calls
 *	dev_put to indicate they have finished with it.
 */

857
struct net_device *dev_get_by_index(struct net *net, int ifindex)
L
Linus Torvalds 已提交
858 859 860
{
	struct net_device *dev;

861 862
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
L
Linus Torvalds 已提交
863 864
	if (dev)
		dev_hold(dev);
865
	rcu_read_unlock();
L
Linus Torvalds 已提交
866 867
	return dev;
}
E
Eric Dumazet 已提交
868
EXPORT_SYMBOL(dev_get_by_index);
L
Linus Torvalds 已提交
869

870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894
/**
 *	dev_get_by_napi_id - find a device by napi_id
 *	@napi_id: ID of the NAPI struct
 *
 *	Search for an interface by NAPI ID. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not had
 *	its reference counter increased so the caller must be careful
 *	about locking. The caller must hold RCU lock.
 */

struct net_device *dev_get_by_napi_id(unsigned int napi_id)
{
	struct napi_struct *napi;

	WARN_ON_ONCE(!rcu_read_lock_held());

	if (napi_id < MIN_NAPI_ID)
		return NULL;

	napi = napi_by_id(napi_id);

	return napi ? napi->dev : NULL;
}
EXPORT_SYMBOL(dev_get_by_napi_id);

895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928
/**
 *	netdev_get_name - get a netdevice name, knowing its ifindex.
 *	@net: network namespace
 *	@name: a pointer to the buffer where the name will be stored.
 *	@ifindex: the ifindex of the interface to get the name from.
 *
 *	The use of raw_seqcount_begin() and cond_resched() before
 *	retrying is required as we want to give the writers a chance
 *	to complete when CONFIG_PREEMPT is not set.
 */
int netdev_get_name(struct net *net, char *name, int ifindex)
{
	struct net_device *dev;
	unsigned int seq;

retry:
	seq = raw_seqcount_begin(&devnet_rename_seq);
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
	if (!dev) {
		rcu_read_unlock();
		return -ENODEV;
	}

	strcpy(name, dev->name);
	rcu_read_unlock();
	if (read_seqcount_retry(&devnet_rename_seq, seq)) {
		cond_resched();
		goto retry;
	}

	return 0;
}

L
Linus Torvalds 已提交
929
/**
930
 *	dev_getbyhwaddr_rcu - find a device by its hardware address
931
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
932 933 934 935
 *	@type: media type of device
 *	@ha: hardware address
 *
 *	Search for an interface by MAC address. Returns NULL if the device
E
Eric Dumazet 已提交
936 937
 *	is not found or a pointer to the device.
 *	The caller must hold RCU or RTNL.
938
 *	The returned device has not had its ref count increased
L
Linus Torvalds 已提交
939 940 941 942
 *	and the caller must therefore be careful about locking
 *
 */

943 944
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
				       const char *ha)
L
Linus Torvalds 已提交
945 946 947
{
	struct net_device *dev;

948
	for_each_netdev_rcu(net, dev)
L
Linus Torvalds 已提交
949 950
		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
951 952 953
			return dev;

	return NULL;
L
Linus Torvalds 已提交
954
}
955
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
956

957
struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
L
Linus Torvalds 已提交
958 959 960
{
	struct net_device *dev;

961
	ASSERT_RTNL();
962
	for_each_netdev(net, dev)
963
		if (dev->type == type)
964 965 966
			return dev;

	return NULL;
967 968 969
}
EXPORT_SYMBOL(__dev_getfirstbyhwtype);

970
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
971
{
972
	struct net_device *dev, *ret = NULL;
973

974 975 976 977 978 979 980 981 982
	rcu_read_lock();
	for_each_netdev_rcu(net, dev)
		if (dev->type == type) {
			dev_hold(dev);
			ret = dev;
			break;
		}
	rcu_read_unlock();
	return ret;
L
Linus Torvalds 已提交
983 984 985 986
}
EXPORT_SYMBOL(dev_getfirstbyhwtype);

/**
987
 *	__dev_get_by_flags - find any device with given flags
988
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
989 990 991 992
 *	@if_flags: IFF_* values
 *	@mask: bitmask of bits in if_flags to check
 *
 *	Search for any interface with the given flags. Returns NULL if a device
E
Eric Dumazet 已提交
993
 *	is not found or a pointer to the device. Must be called inside
994
 *	rtnl_lock(), and result refcount is unchanged.
L
Linus Torvalds 已提交
995 996
 */

997 998
struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
				      unsigned short mask)
L
Linus Torvalds 已提交
999
{
1000
	struct net_device *dev, *ret;
L
Linus Torvalds 已提交
1001

1002 1003
	ASSERT_RTNL();

1004
	ret = NULL;
1005
	for_each_netdev(net, dev) {
L
Linus Torvalds 已提交
1006
		if (((dev->flags ^ if_flags) & mask) == 0) {
1007
			ret = dev;
L
Linus Torvalds 已提交
1008 1009 1010
			break;
		}
	}
1011
	return ret;
L
Linus Torvalds 已提交
1012
}
1013
EXPORT_SYMBOL(__dev_get_by_flags);
L
Linus Torvalds 已提交
1014 1015 1016 1017 1018 1019

/**
 *	dev_valid_name - check if name is okay for network device
 *	@name: name string
 *
 *	Network device names need to be valid file names to
1020 1021
 *	to allow sysfs to work.  We also disallow any kind of
 *	whitespace.
L
Linus Torvalds 已提交
1022
 */
1023
bool dev_valid_name(const char *name)
L
Linus Torvalds 已提交
1024
{
1025
	if (*name == '\0')
1026
		return false;
1027
	if (strlen(name) >= IFNAMSIZ)
1028
		return false;
1029
	if (!strcmp(name, ".") || !strcmp(name, ".."))
1030
		return false;
1031 1032

	while (*name) {
1033
		if (*name == '/' || *name == ':' || isspace(*name))
1034
			return false;
1035 1036
		name++;
	}
1037
	return true;
L
Linus Torvalds 已提交
1038
}
E
Eric Dumazet 已提交
1039
EXPORT_SYMBOL(dev_valid_name);
L
Linus Torvalds 已提交
1040 1041

/**
1042 1043
 *	__dev_alloc_name - allocate a name for a device
 *	@net: network namespace to allocate the device name in
L
Linus Torvalds 已提交
1044
 *	@name: name format string
1045
 *	@buf:  scratch buffer and result name string
L
Linus Torvalds 已提交
1046 1047
 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
S
Stephen Hemminger 已提交
1048 1049 1050 1051 1052 1053
 *	id. It scans list of devices to build up a free map, then chooses
 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 *	while allocating the name and adding the device in order to avoid
 *	duplicates.
 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 *	Returns the number of the unit assigned or a negative errno code.
L
Linus Torvalds 已提交
1054 1055
 */

1056
static int __dev_alloc_name(struct net *net, const char *name, char *buf)
L
Linus Torvalds 已提交
1057 1058 1059 1060
{
	int i = 0;
	const char *p;
	const int max_netdevices = 8*PAGE_SIZE;
S
Stephen Hemminger 已提交
1061
	unsigned long *inuse;
L
Linus Torvalds 已提交
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074
	struct net_device *d;

	p = strnchr(name, IFNAMSIZ-1, '%');
	if (p) {
		/*
		 * Verify the string as this thing may have come from
		 * the user.  There must be either one "%d" and no other "%"
		 * characters.
		 */
		if (p[1] != 'd' || strchr(p + 2, '%'))
			return -EINVAL;

		/* Use one page as a bit array of possible slots */
S
Stephen Hemminger 已提交
1075
		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
L
Linus Torvalds 已提交
1076 1077 1078
		if (!inuse)
			return -ENOMEM;

1079
		for_each_netdev(net, d) {
L
Linus Torvalds 已提交
1080 1081 1082 1083 1084 1085
			if (!sscanf(d->name, name, &i))
				continue;
			if (i < 0 || i >= max_netdevices)
				continue;

			/*  avoid cases where sscanf is not exact inverse of printf */
1086
			snprintf(buf, IFNAMSIZ, name, i);
L
Linus Torvalds 已提交
1087 1088 1089 1090 1091 1092 1093 1094
			if (!strncmp(buf, d->name, IFNAMSIZ))
				set_bit(i, inuse);
		}

		i = find_first_zero_bit(inuse, max_netdevices);
		free_page((unsigned long) inuse);
	}

1095 1096
	if (buf != name)
		snprintf(buf, IFNAMSIZ, name, i);
1097
	if (!__dev_get_by_name(net, buf))
L
Linus Torvalds 已提交
1098 1099 1100 1101 1102 1103 1104 1105 1106
		return i;

	/* It is possible to run out of possible slots
	 * when the name is long and there isn't enough space left
	 * for the digits, or if all bits are used.
	 */
	return -ENFILE;
}

1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126
/**
 *	dev_alloc_name - allocate a name for a device
 *	@dev: device
 *	@name: name format string
 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
 *	id. It scans list of devices to build up a free map, then chooses
 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 *	while allocating the name and adding the device in order to avoid
 *	duplicates.
 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 *	Returns the number of the unit assigned or a negative errno code.
 */

int dev_alloc_name(struct net_device *dev, const char *name)
{
	char buf[IFNAMSIZ];
	struct net *net;
	int ret;

1127 1128
	BUG_ON(!dev_net(dev));
	net = dev_net(dev);
1129 1130 1131 1132 1133
	ret = __dev_alloc_name(net, name, buf);
	if (ret >= 0)
		strlcpy(dev->name, buf, IFNAMSIZ);
	return ret;
}
E
Eric Dumazet 已提交
1134
EXPORT_SYMBOL(dev_alloc_name);
1135

1136 1137 1138
static int dev_alloc_name_ns(struct net *net,
			     struct net_device *dev,
			     const char *name)
1139
{
1140 1141
	char buf[IFNAMSIZ];
	int ret;
1142

1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153
	ret = __dev_alloc_name(net, name, buf);
	if (ret >= 0)
		strlcpy(dev->name, buf, IFNAMSIZ);
	return ret;
}

static int dev_get_valid_name(struct net *net,
			      struct net_device *dev,
			      const char *name)
{
	BUG_ON(!net);
1154

1155 1156 1157
	if (!dev_valid_name(name))
		return -EINVAL;

1158
	if (strchr(name, '%'))
1159
		return dev_alloc_name_ns(net, dev, name);
1160 1161
	else if (__dev_get_by_name(net, name))
		return -EEXIST;
1162 1163
	else if (dev->name != name)
		strlcpy(dev->name, name, IFNAMSIZ);
1164 1165 1166

	return 0;
}
L
Linus Torvalds 已提交
1167 1168 1169 1170 1171 1172 1173 1174 1175

/**
 *	dev_change_name - change name of a device
 *	@dev: device
 *	@newname: name (or format string) must be at least IFNAMSIZ
 *
 *	Change name of a device, can pass format strings "eth%d".
 *	for wildcarding.
 */
1176
int dev_change_name(struct net_device *dev, const char *newname)
L
Linus Torvalds 已提交
1177
{
1178
	unsigned char old_assign_type;
1179
	char oldname[IFNAMSIZ];
L
Linus Torvalds 已提交
1180
	int err = 0;
1181
	int ret;
1182
	struct net *net;
L
Linus Torvalds 已提交
1183 1184

	ASSERT_RTNL();
1185
	BUG_ON(!dev_net(dev));
L
Linus Torvalds 已提交
1186

1187
	net = dev_net(dev);
L
Linus Torvalds 已提交
1188 1189 1190
	if (dev->flags & IFF_UP)
		return -EBUSY;

1191
	write_seqcount_begin(&devnet_rename_seq);
1192 1193

	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1194
		write_seqcount_end(&devnet_rename_seq);
1195
		return 0;
1196
	}
1197

1198 1199
	memcpy(oldname, dev->name, IFNAMSIZ);

1200
	err = dev_get_valid_name(net, dev, newname);
1201
	if (err < 0) {
1202
		write_seqcount_end(&devnet_rename_seq);
1203
		return err;
1204
	}
L
Linus Torvalds 已提交
1205

1206 1207 1208
	if (oldname[0] && !strchr(oldname, '%'))
		netdev_info(dev, "renamed from %s\n", oldname);

1209 1210 1211
	old_assign_type = dev->name_assign_type;
	dev->name_assign_type = NET_NAME_RENAMED;

1212
rollback:
1213 1214 1215
	ret = device_rename(&dev->dev, dev->name);
	if (ret) {
		memcpy(dev->name, oldname, IFNAMSIZ);
1216
		dev->name_assign_type = old_assign_type;
1217
		write_seqcount_end(&devnet_rename_seq);
1218
		return ret;
1219
	}
1220

1221
	write_seqcount_end(&devnet_rename_seq);
1222

1223 1224
	netdev_adjacent_rename_links(dev, oldname);

1225
	write_lock_bh(&dev_base_lock);
1226
	hlist_del_rcu(&dev->name_hlist);
1227 1228 1229 1230 1231 1232
	write_unlock_bh(&dev_base_lock);

	synchronize_rcu();

	write_lock_bh(&dev_base_lock);
	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1233 1234
	write_unlock_bh(&dev_base_lock);

1235
	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1236 1237 1238
	ret = notifier_to_errno(ret);

	if (ret) {
1239 1240
		/* err >= 0 after dev_alloc_name() or stores the first errno */
		if (err >= 0) {
1241
			err = ret;
1242
			write_seqcount_begin(&devnet_rename_seq);
1243
			memcpy(dev->name, oldname, IFNAMSIZ);
1244
			memcpy(oldname, newname, IFNAMSIZ);
1245 1246
			dev->name_assign_type = old_assign_type;
			old_assign_type = NET_NAME_RENAMED;
1247
			goto rollback;
1248
		} else {
1249
			pr_err("%s: name change rollback failed: %d\n",
1250
			       dev->name, ret);
1251 1252
		}
	}
L
Linus Torvalds 已提交
1253 1254 1255 1256

	return err;
}

1257 1258 1259 1260
/**
 *	dev_set_alias - change ifalias of a device
 *	@dev: device
 *	@alias: name up to IFALIASZ
1261
 *	@len: limit of bytes to copy from info
1262 1263 1264 1265 1266
 *
 *	Set ifalias for a device,
 */
int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
{
1267 1268
	char *new_ifalias;

1269 1270 1271 1272 1273
	ASSERT_RTNL();

	if (len >= IFALIASZ)
		return -EINVAL;

1274
	if (!len) {
1275 1276
		kfree(dev->ifalias);
		dev->ifalias = NULL;
1277 1278 1279
		return 0;
	}

1280 1281
	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
	if (!new_ifalias)
1282
		return -ENOMEM;
1283
	dev->ifalias = new_ifalias;
1284 1285
	memcpy(dev->ifalias, alias, len);
	dev->ifalias[len] = 0;
1286 1287 1288 1289 1290

	return len;
}


1291
/**
S
Stephen Hemminger 已提交
1292
 *	netdev_features_change - device changes features
1293 1294 1295 1296 1297 1298
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
1299
	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1300 1301 1302
}
EXPORT_SYMBOL(netdev_features_change);

L
Linus Torvalds 已提交
1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313
/**
 *	netdev_state_change - device changes state
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed state. This function calls
 *	the notifier chains for netdev_chain and sends a NEWLINK message
 *	to the routing socket.
 */
void netdev_state_change(struct net_device *dev)
{
	if (dev->flags & IFF_UP) {
1314 1315 1316 1317 1318
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = 0;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
1319
		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
L
Linus Torvalds 已提交
1320 1321
	}
}
E
Eric Dumazet 已提交
1322
EXPORT_SYMBOL(netdev_state_change);
L
Linus Torvalds 已提交
1323

1324
/**
1325 1326
 * netdev_notify_peers - notify network peers about existence of @dev
 * @dev: network device
1327 1328 1329 1330 1331 1332 1333 1334
 *
 * Generate traffic such that interested network peers are aware of
 * @dev, such as by generating a gratuitous ARP. This may be used when
 * a device wants to inform the rest of the network about some sort of
 * reconfiguration such as a failover event or virtual machine
 * migration.
 */
void netdev_notify_peers(struct net_device *dev)
1335
{
1336 1337
	rtnl_lock();
	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1338
	call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
1339
	rtnl_unlock();
1340
}
1341
EXPORT_SYMBOL(netdev_notify_peers);
1342

1343
static int __dev_open(struct net_device *dev)
L
Linus Torvalds 已提交
1344
{
1345
	const struct net_device_ops *ops = dev->netdev_ops;
1346
	int ret;
L
Linus Torvalds 已提交
1347

1348 1349
	ASSERT_RTNL();

L
Linus Torvalds 已提交
1350 1351 1352
	if (!netif_device_present(dev))
		return -ENODEV;

1353 1354 1355 1356
	/* Block netpoll from trying to do any rx path servicing.
	 * If we don't do this there is a chance ndo_poll_controller
	 * or ndo_poll may be running while we open the device
	 */
1357
	netpoll_poll_disable(dev);
1358

1359 1360 1361 1362 1363
	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

L
Linus Torvalds 已提交
1364
	set_bit(__LINK_STATE_START, &dev->state);
1365

1366 1367
	if (ops->ndo_validate_addr)
		ret = ops->ndo_validate_addr(dev);
1368

1369 1370
	if (!ret && ops->ndo_open)
		ret = ops->ndo_open(dev);
L
Linus Torvalds 已提交
1371

1372
	netpoll_poll_enable(dev);
1373

1374 1375 1376
	if (ret)
		clear_bit(__LINK_STATE_START, &dev->state);
	else {
L
Linus Torvalds 已提交
1377
		dev->flags |= IFF_UP;
1378
		dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
1379
		dev_activate(dev);
1380
		add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
1381
	}
1382

L
Linus Torvalds 已提交
1383 1384 1385 1386
	return ret;
}

/**
1387 1388
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
L
Linus Torvalds 已提交
1389
 *
1390 1391 1392 1393 1394 1395 1396
 *	Takes a device from down to up state. The device's private open
 *	function is invoked and then the multicast lists are loaded. Finally
 *	the device is moved into the up state and a %NETDEV_UP message is
 *	sent to the netdev notifier chain.
 *
 *	Calling this function on an active interface is a nop. On a failure
 *	a negative errno code is returned.
L
Linus Torvalds 已提交
1397
 */
1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408
int dev_open(struct net_device *dev)
{
	int ret;

	if (dev->flags & IFF_UP)
		return 0;

	ret = __dev_open(dev);
	if (ret < 0)
		return ret;

1409
	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1410 1411 1412 1413 1414 1415
	call_netdevice_notifiers(NETDEV_UP, dev);

	return ret;
}
EXPORT_SYMBOL(dev_open);

1416
static int __dev_close_many(struct list_head *head)
L
Linus Torvalds 已提交
1417
{
1418
	struct net_device *dev;
1419

1420
	ASSERT_RTNL();
1421 1422
	might_sleep();

1423
	list_for_each_entry(dev, head, close_list) {
1424
		/* Temporarily disable netpoll until the interface is down */
1425
		netpoll_poll_disable(dev);
1426

1427
		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
L
Linus Torvalds 已提交
1428

1429
		clear_bit(__LINK_STATE_START, &dev->state);
L
Linus Torvalds 已提交
1430

1431 1432 1433 1434 1435 1436
		/* Synchronize to scheduled poll. We cannot touch poll list, it
		 * can be even on different cpu. So just clear netif_running().
		 *
		 * dev->stop() will invoke napi_disable() on all of it's
		 * napi_struct instances on this device.
		 */
1437
		smp_mb__after_atomic(); /* Commit netif_running(). */
1438
	}
L
Linus Torvalds 已提交
1439

1440
	dev_deactivate_many(head);
1441

1442
	list_for_each_entry(dev, head, close_list) {
1443
		const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
1444

1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455
		/*
		 *	Call the device specific close. This cannot fail.
		 *	Only if device is UP
		 *
		 *	We allow it to be called even after a DETACH hot-plug
		 *	event.
		 */
		if (ops->ndo_stop)
			ops->ndo_stop(dev);

		dev->flags &= ~IFF_UP;
1456
		netpoll_poll_enable(dev);
1457 1458 1459 1460 1461 1462 1463
	}

	return 0;
}

static int __dev_close(struct net_device *dev)
{
1464
	int retval;
1465 1466
	LIST_HEAD(single);

1467
	list_add(&dev->close_list, &single);
1468 1469
	retval = __dev_close_many(&single);
	list_del(&single);
1470

1471
	return retval;
1472 1473
}

1474
int dev_close_many(struct list_head *head, bool unlink)
1475 1476
{
	struct net_device *dev, *tmp;
L
Linus Torvalds 已提交
1477

1478 1479
	/* Remove the devices that don't need to be closed */
	list_for_each_entry_safe(dev, tmp, head, close_list)
1480
		if (!(dev->flags & IFF_UP))
1481
			list_del_init(&dev->close_list);
1482 1483

	__dev_close_many(head);
L
Linus Torvalds 已提交
1484

1485
	list_for_each_entry_safe(dev, tmp, head, close_list) {
1486
		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1487
		call_netdevice_notifiers(NETDEV_DOWN, dev);
1488 1489
		if (unlink)
			list_del_init(&dev->close_list);
1490
	}
1491 1492 1493

	return 0;
}
1494
EXPORT_SYMBOL(dev_close_many);
1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506

/**
 *	dev_close - shutdown an interface.
 *	@dev: device to shutdown
 *
 *	This function moves an active device into down state. A
 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
 *	chain.
 */
int dev_close(struct net_device *dev)
{
1507 1508
	if (dev->flags & IFF_UP) {
		LIST_HEAD(single);
L
Linus Torvalds 已提交
1509

1510
		list_add(&dev->close_list, &single);
1511
		dev_close_many(&single, true);
1512 1513
		list_del(&single);
	}
1514
	return 0;
L
Linus Torvalds 已提交
1515
}
E
Eric Dumazet 已提交
1516
EXPORT_SYMBOL(dev_close);
L
Linus Torvalds 已提交
1517 1518


1519 1520 1521 1522 1523 1524 1525 1526 1527 1528
/**
 *	dev_disable_lro - disable Large Receive Offload on a device
 *	@dev: device
 *
 *	Disable Large Receive Offload (LRO) on a net device.  Must be
 *	called under RTNL.  This is needed if received packets may be
 *	forwarded to another interface.
 */
void dev_disable_lro(struct net_device *dev)
{
1529 1530
	struct net_device *lower_dev;
	struct list_head *iter;
1531

M
Michał Mirosław 已提交
1532 1533
	dev->wanted_features &= ~NETIF_F_LRO;
	netdev_update_features(dev);
1534

1535 1536
	if (unlikely(dev->features & NETIF_F_LRO))
		netdev_WARN(dev, "failed to disable LRO!\n");
1537 1538 1539

	netdev_for_each_lower_dev(dev, lower_dev, iter)
		dev_disable_lro(lower_dev);
1540 1541 1542
}
EXPORT_SYMBOL(dev_disable_lro);

1543 1544 1545 1546 1547 1548 1549 1550
static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
				   struct net_device *dev)
{
	struct netdev_notifier_info info;

	netdev_notifier_info_init(&info, dev);
	return nb->notifier_call(nb, val, &info);
}
1551

1552 1553
static int dev_boot_phase = 1;

L
Linus Torvalds 已提交
1554
/**
1555 1556
 * register_netdevice_notifier - register a network notifier block
 * @nb: notifier
L
Linus Torvalds 已提交
1557
 *
1558 1559 1560 1561
 * Register a notifier to be called when network device events occur.
 * The notifier passed is linked into the kernel structures and must
 * not be reused until it has been unregistered. A negative errno code
 * is returned on a failure.
L
Linus Torvalds 已提交
1562
 *
1563 1564 1565
 * When registered all registration and up events are replayed
 * to the new notifier to allow device to have a race free
 * view of the network device list.
L
Linus Torvalds 已提交
1566 1567 1568 1569 1570
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
1571
	struct net_device *last;
1572
	struct net *net;
L
Linus Torvalds 已提交
1573 1574 1575
	int err;

	rtnl_lock();
1576
	err = raw_notifier_chain_register(&netdev_chain, nb);
1577 1578
	if (err)
		goto unlock;
1579 1580 1581 1582
	if (dev_boot_phase)
		goto unlock;
	for_each_net(net) {
		for_each_netdev(net, dev) {
1583
			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1584 1585 1586 1587 1588 1589
			err = notifier_to_errno(err);
			if (err)
				goto rollback;

			if (!(dev->flags & IFF_UP))
				continue;
L
Linus Torvalds 已提交
1590

1591
			call_netdevice_notifier(nb, NETDEV_UP, dev);
1592
		}
L
Linus Torvalds 已提交
1593
	}
1594 1595

unlock:
L
Linus Torvalds 已提交
1596 1597
	rtnl_unlock();
	return err;
1598 1599 1600

rollback:
	last = dev;
1601 1602 1603
	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev == last)
1604
				goto outroll;
1605

1606
			if (dev->flags & IFF_UP) {
1607 1608 1609
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1610
			}
1611
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1612 1613
		}
	}
1614

1615
outroll:
1616
	raw_notifier_chain_unregister(&netdev_chain, nb);
1617
	goto unlock;
L
Linus Torvalds 已提交
1618
}
E
Eric Dumazet 已提交
1619
EXPORT_SYMBOL(register_netdevice_notifier);
L
Linus Torvalds 已提交
1620 1621

/**
1622 1623
 * unregister_netdevice_notifier - unregister a network notifier block
 * @nb: notifier
L
Linus Torvalds 已提交
1624
 *
1625 1626 1627 1628
 * Unregister a notifier previously registered by
 * register_netdevice_notifier(). The notifier is unlinked into the
 * kernel structures and may then be reused. A negative errno code
 * is returned on a failure.
1629
 *
1630 1631 1632
 * After unregistering unregister and down device events are synthesized
 * for all devices on the device list to the removed notifier to remove
 * the need for special case cleanup code.
L
Linus Torvalds 已提交
1633 1634 1635 1636
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
1637 1638
	struct net_device *dev;
	struct net *net;
1639 1640 1641
	int err;

	rtnl_lock();
1642
	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1643 1644 1645 1646 1647 1648
	if (err)
		goto unlock;

	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev->flags & IFF_UP) {
1649 1650 1651
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1652
			}
1653
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1654 1655 1656
		}
	}
unlock:
1657 1658
	rtnl_unlock();
	return err;
L
Linus Torvalds 已提交
1659
}
E
Eric Dumazet 已提交
1660
EXPORT_SYMBOL(unregister_netdevice_notifier);
L
Linus Torvalds 已提交
1661

1662 1663 1664 1665 1666 1667 1668 1669 1670 1671
/**
 *	call_netdevice_notifiers_info - call all network notifier blocks
 *	@val: value passed unmodified to notifier function
 *	@dev: net_device pointer passed unmodified to notifier function
 *	@info: notifier information data
 *
 *	Call all network notifier blocks.  Parameters and return value
 *	are as for raw_notifier_call_chain().
 */

S
stephen hemminger 已提交
1672 1673 1674
static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info)
1675 1676 1677 1678 1679 1680
{
	ASSERT_RTNL();
	netdev_notifier_info_init(info, dev);
	return raw_notifier_call_chain(&netdev_chain, val, info);
}

L
Linus Torvalds 已提交
1681 1682 1683
/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
1684
 *      @dev: net_device pointer passed unmodified to notifier function
L
Linus Torvalds 已提交
1685 1686
 *
 *	Call all network notifier blocks.  Parameters and return value
1687
 *	are as for raw_notifier_call_chain().
L
Linus Torvalds 已提交
1688 1689
 */

1690
int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
L
Linus Torvalds 已提交
1691
{
1692 1693 1694
	struct netdev_notifier_info info;

	return call_netdevice_notifiers_info(val, dev, &info);
L
Linus Torvalds 已提交
1695
}
1696
EXPORT_SYMBOL(call_netdevice_notifiers);
L
Linus Torvalds 已提交
1697

1698
#ifdef CONFIG_NET_INGRESS
1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713
static struct static_key ingress_needed __read_mostly;

void net_inc_ingress_queue(void)
{
	static_key_slow_inc(&ingress_needed);
}
EXPORT_SYMBOL_GPL(net_inc_ingress_queue);

void net_dec_ingress_queue(void)
{
	static_key_slow_dec(&ingress_needed);
}
EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
#endif

D
Daniel Borkmann 已提交
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729
#ifdef CONFIG_NET_EGRESS
static struct static_key egress_needed __read_mostly;

void net_inc_egress_queue(void)
{
	static_key_slow_inc(&egress_needed);
}
EXPORT_SYMBOL_GPL(net_inc_egress_queue);

void net_dec_egress_queue(void)
{
	static_key_slow_dec(&egress_needed);
}
EXPORT_SYMBOL_GPL(net_dec_egress_queue);
#endif

1730
static struct static_key netstamp_needed __read_mostly;
1731 1732
#ifdef HAVE_JUMP_LABEL
static atomic_t netstamp_needed_deferred;
1733
static atomic_t netstamp_wanted;
1734
static void netstamp_clear(struct work_struct *work)
L
Linus Torvalds 已提交
1735
{
1736
	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1737
	int wanted;
1738

1739 1740 1741 1742 1743
	wanted = atomic_add_return(deferred, &netstamp_wanted);
	if (wanted > 0)
		static_key_enable(&netstamp_needed);
	else
		static_key_disable(&netstamp_needed);
1744 1745
}
static DECLARE_WORK(netstamp_work, netstamp_clear);
1746
#endif
1747 1748 1749

void net_enable_timestamp(void)
{
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762
#ifdef HAVE_JUMP_LABEL
	int wanted;

	while (1) {
		wanted = atomic_read(&netstamp_wanted);
		if (wanted <= 0)
			break;
		if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted)
			return;
	}
	atomic_inc(&netstamp_needed_deferred);
	schedule_work(&netstamp_work);
#else
1763
	static_key_slow_inc(&netstamp_needed);
1764
#endif
L
Linus Torvalds 已提交
1765
}
E
Eric Dumazet 已提交
1766
EXPORT_SYMBOL(net_enable_timestamp);
L
Linus Torvalds 已提交
1767 1768 1769

void net_disable_timestamp(void)
{
1770
#ifdef HAVE_JUMP_LABEL
1771 1772 1773 1774 1775 1776 1777 1778 1779 1780
	int wanted;

	while (1) {
		wanted = atomic_read(&netstamp_wanted);
		if (wanted <= 1)
			break;
		if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted)
			return;
	}
	atomic_dec(&netstamp_needed_deferred);
1781 1782
	schedule_work(&netstamp_work);
#else
1783
	static_key_slow_dec(&netstamp_needed);
1784
#endif
L
Linus Torvalds 已提交
1785
}
E
Eric Dumazet 已提交
1786
EXPORT_SYMBOL(net_disable_timestamp);
L
Linus Torvalds 已提交
1787

E
Eric Dumazet 已提交
1788
static inline void net_timestamp_set(struct sk_buff *skb)
L
Linus Torvalds 已提交
1789
{
T
Thomas Gleixner 已提交
1790
	skb->tstamp = 0;
1791
	if (static_key_false(&netstamp_needed))
1792
		__net_timestamp(skb);
L
Linus Torvalds 已提交
1793 1794
}

1795
#define net_timestamp_check(COND, SKB)			\
1796
	if (static_key_false(&netstamp_needed)) {		\
T
Thomas Gleixner 已提交
1797
		if ((COND) && !(SKB)->tstamp)	\
1798 1799
			__net_timestamp(SKB);		\
	}						\
E
Eric Dumazet 已提交
1800

1801
bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819
{
	unsigned int len;

	if (!(dev->flags & IFF_UP))
		return false;

	len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
	if (skb->len <= len)
		return true;

	/* if TSO is enabled, we don't care about the length as the packet
	 * could be forwarded without being segmented before
	 */
	if (skb_is_gso(skb))
		return true;

	return false;
}
1820
EXPORT_SYMBOL_GPL(is_skb_forwardable);
1821

H
Herbert Xu 已提交
1822 1823
int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
1824
	int ret = ____dev_forward_skb(dev, skb);
H
Herbert Xu 已提交
1825

1826 1827 1828 1829
	if (likely(!ret)) {
		skb->protocol = eth_type_trans(skb, dev);
		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
	}
H
Herbert Xu 已提交
1830

1831
	return ret;
H
Herbert Xu 已提交
1832 1833 1834
}
EXPORT_SYMBOL_GPL(__dev_forward_skb);

1835 1836 1837 1838 1839 1840 1841 1842
/**
 * dev_forward_skb - loopback an skb to another netif
 *
 * @dev: destination network device
 * @skb: buffer to forward
 *
 * return values:
 *	NET_RX_SUCCESS	(no congestion)
1843
 *	NET_RX_DROP     (packet was dropped, but freed)
1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854
 *
 * dev_forward_skb can be used for injecting an skb from the
 * start_xmit function of one device into the receive queue
 * of another device.
 *
 * The receiving device may be in another namespace, so
 * we have to clear all information in the skb that could
 * impact namespace isolation.
 */
int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
H
Herbert Xu 已提交
1855
	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1856 1857 1858
}
EXPORT_SYMBOL_GPL(dev_forward_skb);

1859 1860 1861 1862
static inline int deliver_skb(struct sk_buff *skb,
			      struct packet_type *pt_prev,
			      struct net_device *orig_dev)
{
1863 1864
	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
		return -ENOMEM;
1865
	refcount_inc(&skb->users);
1866 1867 1868
	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

1869 1870
static inline void deliver_ptype_list_skb(struct sk_buff *skb,
					  struct packet_type **pt,
1871 1872
					  struct net_device *orig_dev,
					  __be16 type,
1873 1874 1875 1876 1877 1878 1879 1880
					  struct list_head *ptype_list)
{
	struct packet_type *ptype, *pt_prev = *pt;

	list_for_each_entry_rcu(ptype, ptype_list, list) {
		if (ptype->type != type)
			continue;
		if (pt_prev)
1881
			deliver_skb(skb, pt_prev, orig_dev);
1882 1883 1884 1885 1886
		pt_prev = ptype;
	}
	*pt = pt_prev;
}

1887 1888
static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
{
1889
	if (!ptype->af_packet_priv || !skb->sk)
1890 1891 1892 1893 1894 1895 1896 1897 1898 1899
		return false;

	if (ptype->id_match)
		return ptype->id_match(ptype, skb->sk);
	else if ((struct sock *)ptype->af_packet_priv == skb->sk)
		return true;

	return false;
}

L
Linus Torvalds 已提交
1900 1901 1902 1903 1904
/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

1905
void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
L
Linus Torvalds 已提交
1906 1907
{
	struct packet_type *ptype;
1908 1909
	struct sk_buff *skb2 = NULL;
	struct packet_type *pt_prev = NULL;
1910
	struct list_head *ptype_list = &ptype_all;
1911

L
Linus Torvalds 已提交
1912
	rcu_read_lock();
1913 1914
again:
	list_for_each_entry_rcu(ptype, ptype_list, list) {
L
Linus Torvalds 已提交
1915 1916 1917
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
1918 1919
		if (skb_loop_sk(ptype, skb))
			continue;
1920

1921 1922 1923 1924 1925
		if (pt_prev) {
			deliver_skb(skb2, pt_prev, skb->dev);
			pt_prev = ptype;
			continue;
		}
L
Linus Torvalds 已提交
1926

1927 1928 1929 1930
		/* need to clone skb, done only once */
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			goto out_unlock;
1931

1932
		net_timestamp_set(skb2);
L
Linus Torvalds 已提交
1933

1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945
		/* skb->nh should be correctly
		 * set by sender, so that the second statement is
		 * just protection against buggy protocols.
		 */
		skb_reset_mac_header(skb2);

		if (skb_network_header(skb2) < skb2->data ||
		    skb_network_header(skb2) > skb_tail_pointer(skb2)) {
			net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
					     ntohs(skb2->protocol),
					     dev->name);
			skb_reset_network_header(skb2);
L
Linus Torvalds 已提交
1946
		}
1947 1948 1949 1950 1951 1952 1953 1954 1955

		skb2->transport_header = skb2->network_header;
		skb2->pkt_type = PACKET_OUTGOING;
		pt_prev = ptype;
	}

	if (ptype_list == &ptype_all) {
		ptype_list = &dev->ptype_all;
		goto again;
L
Linus Torvalds 已提交
1956
	}
1957
out_unlock:
1958 1959
	if (pt_prev)
		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
L
Linus Torvalds 已提交
1960 1961
	rcu_read_unlock();
}
1962
EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
L
Linus Torvalds 已提交
1963

1964 1965
/**
 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976
 * @dev: Network device
 * @txq: number of queues available
 *
 * If real_num_tx_queues is changed the tc mappings may no longer be
 * valid. To resolve this verify the tc mapping remains valid and if
 * not NULL the mapping. With no priorities mapping to this
 * offset/count pair it will no longer be used. In the worst case TC0
 * is invalid nothing can be done so disable priority mappings. If is
 * expected that drivers will fix this mapping if they can before
 * calling netif_set_real_num_tx_queues.
 */
E
Eric Dumazet 已提交
1977
static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1978 1979 1980 1981 1982 1983
{
	int i;
	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];

	/* If TC0 is invalidated disable TC mapping */
	if (tc->offset + tc->count > txq) {
1984
		pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1985 1986 1987 1988 1989 1990 1991 1992 1993 1994
		dev->num_tc = 0;
		return;
	}

	/* Invalidated prio to tc mappings set to TC0 */
	for (i = 1; i < TC_BITMASK + 1; i++) {
		int q = netdev_get_prio_tc_map(dev, i);

		tc = &dev->tc_to_txq[q];
		if (tc->offset + tc->count > txq) {
1995 1996
			pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
				i, q);
1997 1998 1999 2000 2001
			netdev_set_prio_tc_map(dev, i, 0);
		}
	}
}

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
{
	if (dev->num_tc) {
		struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
		int i;

		for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
			if ((txq - tc->offset) < tc->count)
				return i;
		}

		return -1;
	}

	return 0;
}

2019 2020 2021 2022 2023
#ifdef CONFIG_XPS
static DEFINE_MUTEX(xps_map_mutex);
#define xmap_dereference(P)		\
	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))

2024 2025
static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
			     int tci, u16 index)
2026
{
2027 2028
	struct xps_map *map = NULL;
	int pos;
2029

2030
	if (dev_maps)
2031 2032 2033
		map = xmap_dereference(dev_maps->cpu_map[tci]);
	if (!map)
		return false;
2034

2035 2036 2037 2038 2039 2040
	for (pos = map->len; pos--;) {
		if (map->queues[pos] != index)
			continue;

		if (map->len > 1) {
			map->queues[pos] = map->queues[--map->len];
2041
			break;
2042
		}
2043 2044 2045 2046

		RCU_INIT_POINTER(dev_maps->cpu_map[tci], NULL);
		kfree_rcu(map, rcu);
		return false;
2047 2048
	}

2049
	return true;
2050 2051
}

2052 2053 2054 2055
static bool remove_xps_queue_cpu(struct net_device *dev,
				 struct xps_dev_maps *dev_maps,
				 int cpu, u16 offset, u16 count)
{
2056 2057 2058
	int num_tc = dev->num_tc ? : 1;
	bool active = false;
	int tci;
2059

2060 2061 2062 2063 2064 2065 2066 2067 2068
	for (tci = cpu * num_tc; num_tc--; tci++) {
		int i, j;

		for (i = count, j = offset; i--; j++) {
			if (!remove_xps_queue(dev_maps, cpu, j))
				break;
		}

		active |= i < 0;
2069 2070
	}

2071
	return active;
2072 2073 2074 2075
}

static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
				   u16 count)
2076 2077
{
	struct xps_dev_maps *dev_maps;
2078
	int cpu, i;
2079 2080 2081 2082 2083 2084 2085 2086
	bool active = false;

	mutex_lock(&xps_map_mutex);
	dev_maps = xmap_dereference(dev->xps_maps);

	if (!dev_maps)
		goto out_no_maps;

2087 2088 2089
	for_each_possible_cpu(cpu)
		active |= remove_xps_queue_cpu(dev, dev_maps, cpu,
					       offset, count);
2090 2091

	if (!active) {
2092 2093 2094 2095
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

2096
	for (i = offset + (count - 1); count--; i--)
2097 2098 2099
		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     NUMA_NO_NODE);

2100 2101 2102 2103
out_no_maps:
	mutex_unlock(&xps_map_mutex);
}

2104 2105 2106 2107 2108
static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
{
	netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
}

2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143
static struct xps_map *expand_xps_map(struct xps_map *map,
				      int cpu, u16 index)
{
	struct xps_map *new_map;
	int alloc_len = XPS_MIN_MAP_ALLOC;
	int i, pos;

	for (pos = 0; map && pos < map->len; pos++) {
		if (map->queues[pos] != index)
			continue;
		return map;
	}

	/* Need to add queue to this CPU's existing map */
	if (map) {
		if (pos < map->alloc_len)
			return map;

		alloc_len = map->alloc_len * 2;
	}

	/* Need to allocate new map to store queue on this CPU's map */
	new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
			       cpu_to_node(cpu));
	if (!new_map)
		return NULL;

	for (i = 0; i < pos; i++)
		new_map->queues[i] = map->queues[i];
	new_map->alloc_len = alloc_len;
	new_map->len = pos;

	return new_map;
}

2144 2145
int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
			u16 index)
2146
{
2147
	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2148 2149
	int i, cpu, tci, numa_node_id = -2;
	int maps_sz, num_tc = 1, tc = 0;
2150
	struct xps_map *map, *new_map;
2151
	bool active = false;
2152

2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163
	if (dev->num_tc) {
		num_tc = dev->num_tc;
		tc = netdev_txq_to_tc(dev, index);
		if (tc < 0)
			return -EINVAL;
	}

	maps_sz = XPS_DEV_MAPS_SIZE(num_tc);
	if (maps_sz < L1_CACHE_BYTES)
		maps_sz = L1_CACHE_BYTES;

2164 2165 2166 2167
	mutex_lock(&xps_map_mutex);

	dev_maps = xmap_dereference(dev->xps_maps);

2168
	/* allocate memory for queue storage */
2169
	for_each_cpu_and(cpu, cpu_online_mask, mask) {
2170 2171
		if (!new_dev_maps)
			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
2172 2173
		if (!new_dev_maps) {
			mutex_unlock(&xps_map_mutex);
2174
			return -ENOMEM;
2175
		}
2176

2177 2178
		tci = cpu * num_tc + tc;
		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[tci]) :
2179 2180 2181 2182 2183 2184
				 NULL;

		map = expand_xps_map(map, cpu, index);
		if (!map)
			goto error;

2185
		RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
2186 2187 2188 2189 2190
	}

	if (!new_dev_maps)
		goto out_no_new_maps;

2191
	for_each_possible_cpu(cpu) {
2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203
		/* copy maps belonging to foreign traffic classes */
		for (i = tc, tci = cpu * num_tc; dev_maps && i--; tci++) {
			/* fill in the new device map from the old device map */
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
		}

		/* We need to explicitly update tci as prevous loop
		 * could break out early if dev_maps is NULL.
		 */
		tci = cpu * num_tc + tc;

2204 2205 2206 2207
		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
			/* add queue to CPU maps */
			int pos = 0;

2208
			map = xmap_dereference(new_dev_maps->cpu_map[tci]);
2209 2210 2211 2212 2213
			while ((pos < map->len) && (map->queues[pos] != index))
				pos++;

			if (pos == map->len)
				map->queues[map->len++] = index;
2214 2215 2216 2217 2218 2219
#ifdef CONFIG_NUMA
			if (numa_node_id == -2)
				numa_node_id = cpu_to_node(cpu);
			else if (numa_node_id != cpu_to_node(cpu))
				numa_node_id = -1;
#endif
2220 2221
		} else if (dev_maps) {
			/* fill in the new device map from the old device map */
2222 2223
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
2224
		}
2225

2226 2227 2228 2229 2230 2231
		/* copy maps belonging to foreign traffic classes */
		for (i = num_tc - tc, tci++; dev_maps && --i; tci++) {
			/* fill in the new device map from the old device map */
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
		}
2232 2233
	}

2234 2235
	rcu_assign_pointer(dev->xps_maps, new_dev_maps);

2236
	/* Cleanup old maps */
2237 2238 2239 2240 2241 2242 2243
	if (!dev_maps)
		goto out_no_old_maps;

	for_each_possible_cpu(cpu) {
		for (i = num_tc, tci = cpu * num_tc; i--; tci++) {
			new_map = xmap_dereference(new_dev_maps->cpu_map[tci]);
			map = xmap_dereference(dev_maps->cpu_map[tci]);
2244 2245 2246
			if (map && map != new_map)
				kfree_rcu(map, rcu);
		}
2247 2248
	}

2249 2250 2251
	kfree_rcu(dev_maps, rcu);

out_no_old_maps:
2252 2253
	dev_maps = new_dev_maps;
	active = true;
2254

2255 2256
out_no_new_maps:
	/* update Tx queue numa node */
2257 2258 2259 2260
	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
				     (numa_node_id >= 0) ? numa_node_id :
				     NUMA_NO_NODE);

2261 2262 2263 2264 2265
	if (!dev_maps)
		goto out_no_maps;

	/* removes queue from unused CPUs */
	for_each_possible_cpu(cpu) {
2266 2267 2268 2269 2270 2271
		for (i = tc, tci = cpu * num_tc; i--; tci++)
			active |= remove_xps_queue(dev_maps, tci, index);
		if (!cpumask_test_cpu(cpu, mask) || !cpu_online(cpu))
			active |= remove_xps_queue(dev_maps, tci, index);
		for (i = num_tc - tc, tci++; --i; tci++)
			active |= remove_xps_queue(dev_maps, tci, index);
2272 2273 2274 2275 2276 2277 2278 2279 2280
	}

	/* free map if not active */
	if (!active) {
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

out_no_maps:
2281 2282 2283 2284
	mutex_unlock(&xps_map_mutex);

	return 0;
error:
2285 2286
	/* remove any maps that we added */
	for_each_possible_cpu(cpu) {
2287 2288 2289 2290 2291 2292 2293 2294
		for (i = num_tc, tci = cpu * num_tc; i--; tci++) {
			new_map = xmap_dereference(new_dev_maps->cpu_map[tci]);
			map = dev_maps ?
			      xmap_dereference(dev_maps->cpu_map[tci]) :
			      NULL;
			if (new_map && new_map != map)
				kfree(new_map);
		}
2295 2296
	}

2297 2298 2299 2300 2301 2302 2303 2304
	mutex_unlock(&xps_map_mutex);

	kfree(new_dev_maps);
	return -ENOMEM;
}
EXPORT_SYMBOL(netif_set_xps_queue);

#endif
2305 2306
void netdev_reset_tc(struct net_device *dev)
{
2307 2308 2309
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320
	dev->num_tc = 0;
	memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
	memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
}
EXPORT_SYMBOL(netdev_reset_tc);

int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
{
	if (tc >= dev->num_tc)
		return -EINVAL;

2321 2322 2323
#ifdef CONFIG_XPS
	netif_reset_xps_queues(dev, offset, count);
#endif
2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334
	dev->tc_to_txq[tc].count = count;
	dev->tc_to_txq[tc].offset = offset;
	return 0;
}
EXPORT_SYMBOL(netdev_set_tc_queue);

int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
{
	if (num_tc > TC_MAX_QUEUE)
		return -EINVAL;

2335 2336 2337
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2338 2339 2340 2341 2342
	dev->num_tc = num_tc;
	return 0;
}
EXPORT_SYMBOL(netdev_set_num_tc);

2343 2344 2345 2346
/*
 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
 */
2347
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2348
{
T
Tom Herbert 已提交
2349 2350
	int rc;

2351 2352
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
2353

2354 2355
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
2356 2357
		ASSERT_RTNL();

T
Tom Herbert 已提交
2358 2359
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
2360 2361 2362
		if (rc)
			return rc;

2363 2364 2365
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

2366
		if (txq < dev->real_num_tx_queues) {
2367
			qdisc_reset_all_tx_gt(dev, txq);
2368 2369 2370 2371
#ifdef CONFIG_XPS
			netif_reset_xps_queues_gt(dev, txq);
#endif
		}
2372
	}
2373 2374 2375

	dev->real_num_tx_queues = txq;
	return 0;
2376 2377
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2378

2379
#ifdef CONFIG_SYSFS
2380 2381 2382 2383 2384 2385 2386
/**
 *	netif_set_real_num_rx_queues - set actual number of RX queues used
 *	@dev: Network device
 *	@rxq: Actual number of RX queues
 *
 *	This must be called either with the rtnl_lock held or before
 *	registration of the net device.  Returns 0 on success, or a
2387 2388
 *	negative error code.  If called before registration, it always
 *	succeeds.
2389 2390 2391 2392 2393
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
2394 2395 2396
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411
	if (dev->reg_state == NETREG_REGISTERED) {
		ASSERT_RTNL();

		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
						  rxq);
		if (rc)
			return rc;
	}

	dev->real_num_rx_queues = rxq;
	return 0;
}
EXPORT_SYMBOL(netif_set_real_num_rx_queues);
#endif

2412 2413
/**
 * netif_get_num_default_rss_queues - default number of RSS queues
2414 2415 2416 2417
 *
 * This routine should set an upper limit on the number of RSS queues
 * used by default by multiqueue devices.
 */
2418
int netif_get_num_default_rss_queues(void)
2419
{
2420 2421
	return is_kdump_kernel() ?
		1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2422 2423 2424
}
EXPORT_SYMBOL(netif_get_num_default_rss_queues);

2425
static void __netif_reschedule(struct Qdisc *q)
2426
{
2427 2428
	struct softnet_data *sd;
	unsigned long flags;
2429

2430
	local_irq_save(flags);
2431
	sd = this_cpu_ptr(&softnet_data);
2432 2433 2434
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
2435 2436 2437 2438 2439 2440 2441 2442
	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_restore(flags);
}

void __netif_schedule(struct Qdisc *q)
{
	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
		__netif_reschedule(q);
2443 2444 2445
}
EXPORT_SYMBOL(__netif_schedule);

2446 2447 2448 2449 2450
struct dev_kfree_skb_cb {
	enum skb_free_reason reason;
};

static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2451
{
2452 2453 2454
	return (struct dev_kfree_skb_cb *)skb->cb;
}

2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479
void netif_schedule_queue(struct netdev_queue *txq)
{
	rcu_read_lock();
	if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
		struct Qdisc *q = rcu_dereference(txq->qdisc);

		__netif_schedule(q);
	}
	rcu_read_unlock();
}
EXPORT_SYMBOL(netif_schedule_queue);

void netif_tx_wake_queue(struct netdev_queue *dev_queue)
{
	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
		struct Qdisc *q;

		rcu_read_lock();
		q = rcu_dereference(dev_queue->qdisc);
		__netif_schedule(q);
		rcu_read_unlock();
	}
}
EXPORT_SYMBOL(netif_tx_wake_queue);

2480
void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2481
{
2482
	unsigned long flags;
2483

2484 2485 2486
	if (unlikely(!skb))
		return;

2487
	if (likely(refcount_read(&skb->users) == 1)) {
2488
		smp_rmb();
2489 2490
		refcount_set(&skb->users, 0);
	} else if (likely(!refcount_dec_and_test(&skb->users))) {
2491
		return;
2492
	}
2493 2494 2495 2496 2497 2498
	get_kfree_skb_cb(skb)->reason = reason;
	local_irq_save(flags);
	skb->next = __this_cpu_read(softnet_data.completion_queue);
	__this_cpu_write(softnet_data.completion_queue, skb);
	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_restore(flags);
2499
}
2500
EXPORT_SYMBOL(__dev_kfree_skb_irq);
2501

2502
void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2503 2504
{
	if (in_irq() || irqs_disabled())
2505
		__dev_kfree_skb_irq(skb, reason);
2506 2507 2508
	else
		dev_kfree_skb(skb);
}
2509
EXPORT_SYMBOL(__dev_kfree_skb_any);
2510 2511


2512 2513 2514 2515 2516 2517
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
2518 2519 2520 2521
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2522
		netif_tx_stop_all_queues(dev);
2523 2524 2525 2526
	}
}
EXPORT_SYMBOL(netif_device_detach);

2527 2528 2529 2530 2531 2532
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
2533 2534 2535 2536
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2537
		netif_tx_wake_all_queues(dev);
2538
		__netdev_watchdog_up(dev);
2539 2540 2541 2542
	}
}
EXPORT_SYMBOL(netif_device_attach);

J
Jiri Pirko 已提交
2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562
/*
 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 * to be used as a distribution range.
 */
u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
		  unsigned int num_tx_queues)
{
	u32 hash;
	u16 qoffset = 0;
	u16 qcount = num_tx_queues;

	if (skb_rx_queue_recorded(skb)) {
		hash = skb_get_rx_queue(skb);
		while (unlikely(hash >= num_tx_queues))
			hash -= num_tx_queues;
		return hash;
	}

	if (dev->num_tc) {
		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
2563

J
Jiri Pirko 已提交
2564 2565 2566 2567 2568 2569 2570 2571
		qoffset = dev->tc_to_txq[tc].offset;
		qcount = dev->tc_to_txq[tc].count;
	}

	return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
}
EXPORT_SYMBOL(__skb_tx_hash);

2572 2573
static void skb_warn_bad_offload(const struct sk_buff *skb)
{
W
Wei Tang 已提交
2574
	static const netdev_features_t null_features;
2575
	struct net_device *dev = skb->dev;
2576
	const char *name = "";
2577

2578 2579 2580
	if (!net_ratelimit())
		return;

2581 2582 2583 2584 2585 2586
	if (dev) {
		if (dev->dev.parent)
			name = dev_driver_string(dev->dev.parent);
		else
			name = netdev_name(dev);
	}
2587 2588
	WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
	     "gso_type=%d ip_summed=%d\n",
2589
	     name, dev ? &dev->features : &null_features,
2590
	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
2591 2592 2593 2594
	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
	     skb_shinfo(skb)->gso_type, skb->ip_summed);
}

L
Linus Torvalds 已提交
2595 2596 2597 2598
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
2599
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
2600
{
2601
	__wsum csum;
2602
	int ret = 0, offset;
L
Linus Torvalds 已提交
2603

2604
	if (skb->ip_summed == CHECKSUM_COMPLETE)
2605 2606 2607
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
2608 2609
		skb_warn_bad_offload(skb);
		return -EINVAL;
L
Linus Torvalds 已提交
2610 2611
	}

2612 2613 2614 2615 2616 2617 2618 2619 2620
	/* Before computing a checksum, we should make sure no frag could
	 * be modified by an external entity : checksum could be wrong.
	 */
	if (skb_has_shared_frag(skb)) {
		ret = __skb_linearize(skb);
		if (ret)
			goto out;
	}

2621
	offset = skb_checksum_start_offset(skb);
2622 2623 2624 2625 2626 2627 2628 2629
	BUG_ON(offset >= skb_headlen(skb));
	csum = skb_checksum(skb, offset, skb->len - offset, 0);

	offset += skb->csum_offset;
	BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));

	if (skb_cloned(skb) &&
	    !skb_clone_writable(skb, offset + sizeof(__sum16))) {
L
Linus Torvalds 已提交
2630 2631 2632 2633 2634
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

2635
	*(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
2636
out_set_summed:
L
Linus Torvalds 已提交
2637
	skb->ip_summed = CHECKSUM_NONE;
2638
out:
L
Linus Torvalds 已提交
2639 2640
	return ret;
}
E
Eric Dumazet 已提交
2641
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
2642

2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678
int skb_crc32c_csum_help(struct sk_buff *skb)
{
	__le32 crc32c_csum;
	int ret = 0, offset, start;

	if (skb->ip_summed != CHECKSUM_PARTIAL)
		goto out;

	if (unlikely(skb_is_gso(skb)))
		goto out;

	/* Before computing a checksum, we should make sure no frag could
	 * be modified by an external entity : checksum could be wrong.
	 */
	if (unlikely(skb_has_shared_frag(skb))) {
		ret = __skb_linearize(skb);
		if (ret)
			goto out;
	}
	start = skb_checksum_start_offset(skb);
	offset = start + offsetof(struct sctphdr, checksum);
	if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
		ret = -EINVAL;
		goto out;
	}
	if (skb_cloned(skb) &&
	    !skb_clone_writable(skb, offset + sizeof(__le32))) {
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}
	crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start,
						  skb->len - start, ~(__u32)0,
						  crc32c_csum_stub));
	*(__le32 *)(skb->data + offset) = crc32c_csum;
	skb->ip_summed = CHECKSUM_NONE;
2679
	skb->csum_not_inet = 0;
2680 2681 2682 2683
out:
	return ret;
}

2684
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2685
{
A
Al Viro 已提交
2686
	__be16 type = skb->protocol;
2687

2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698
	/* Tunnel gso handlers can set protocol to ethernet. */
	if (type == htons(ETH_P_TEB)) {
		struct ethhdr *eth;

		if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
			return 0;

		eth = (struct ethhdr *)skb_mac_header(skb);
		type = eth->h_proto;
	}

2699
	return __vlan_get_protocol(skb, type, depth);
2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711
}

/**
 *	skb_mac_gso_segment - mac layer segmentation handler.
 *	@skb: buffer to segment
 *	@features: features for the output path (see dev->features)
 */
struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
				    netdev_features_t features)
{
	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
	struct packet_offload *ptype;
2712 2713
	int vlan_depth = skb->mac_len;
	__be16 type = skb_network_protocol(skb, &vlan_depth);
2714 2715 2716 2717

	if (unlikely(!type))
		return ERR_PTR(-EINVAL);

2718
	__skb_pull(skb, vlan_depth);
2719 2720

	rcu_read_lock();
2721
	list_for_each_entry_rcu(ptype, &offload_base, list) {
2722 2723
		if (ptype->type == type && ptype->callbacks.gso_segment) {
			segs = ptype->callbacks.gso_segment(skb, features);
2724 2725 2726 2727 2728
			break;
		}
	}
	rcu_read_unlock();

2729
	__skb_push(skb, skb->data - skb_mac_header(skb));
2730

2731 2732
	return segs;
}
2733 2734 2735 2736 2737 2738 2739 2740
EXPORT_SYMBOL(skb_mac_gso_segment);


/* openvswitch calls this on rx path, so we need a different check.
 */
static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
{
	if (tx_path)
2741 2742 2743 2744
		return skb->ip_summed != CHECKSUM_PARTIAL &&
		       skb->ip_summed != CHECKSUM_NONE;

	return skb->ip_summed == CHECKSUM_NONE;
2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756
}

/**
 *	__skb_gso_segment - Perform segmentation on skb.
 *	@skb: buffer to segment
 *	@features: features for the output path (see dev->features)
 *	@tx_path: whether it is called in TX path
 *
 *	This function segments the given skb and returns a list of segments.
 *
 *	It may return NULL if the skb requires no segmentation.  This is
 *	only possible when GSO is used for verifying header integrity.
2757 2758
 *
 *	Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
2759 2760 2761 2762
 */
struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
				  netdev_features_t features, bool tx_path)
{
2763 2764
	struct sk_buff *segs;

2765 2766 2767
	if (unlikely(skb_needs_check(skb, tx_path))) {
		int err;

2768
		/* We're going to init ->check field in TCP or UDP header */
2769 2770
		err = skb_cow_head(skb, 0);
		if (err < 0)
2771 2772 2773
			return ERR_PTR(err);
	}

2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786
	/* Only report GSO partial support if it will enable us to
	 * support segmentation on this frame without needing additional
	 * work.
	 */
	if (features & NETIF_F_GSO_PARTIAL) {
		netdev_features_t partial_features = NETIF_F_GSO_ROBUST;
		struct net_device *dev = skb->dev;

		partial_features |= dev->features & dev->gso_partial_features;
		if (!skb_gso_ok(skb, features | partial_features))
			features &= ~NETIF_F_GSO_PARTIAL;
	}

2787 2788 2789
	BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
		     sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));

2790
	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2791 2792
	SKB_GSO_CB(skb)->encap_level = 0;

2793 2794 2795
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);

2796 2797 2798 2799 2800 2801
	segs = skb_mac_gso_segment(skb, features);

	if (unlikely(skb_needs_check(skb, tx_path)))
		skb_warn_bad_offload(skb);

	return segs;
2802
}
2803
EXPORT_SYMBOL(__skb_gso_segment);
2804

2805 2806 2807 2808 2809
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
2810
		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2811 2812 2813 2814 2815 2816
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
2817 2818 2819 2820 2821
/* Actually, we should eliminate this check as soon as we know, that:
 * 1. IOMMU is present and allows to map all the memory.
 * 2. No high memory really exists on this machine.
 */

2822
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
2823
{
2824
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
2825
	int i;
2826

2827
	if (!(dev->features & NETIF_F_HIGHDMA)) {
2828 2829
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2830

2831
			if (PageHighMem(skb_frag_page(frag)))
2832
				return 1;
2833
		}
2834
	}
L
Linus Torvalds 已提交
2835

2836 2837
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
2838

E
Eric Dumazet 已提交
2839 2840
		if (!pdev)
			return 0;
2841
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2842 2843
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2844

2845 2846 2847 2848
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
2849
#endif
L
Linus Torvalds 已提交
2850 2851 2852
	return 0;
}

2853 2854 2855
/* If MPLS offload request, verify we are testing hardware MPLS features
 * instead of standard features for the netdev.
 */
P
Pravin B Shelar 已提交
2856
#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2857 2858 2859 2860
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
2861
	if (eth_p_mpls(type))
2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874
		features &= skb->dev->mpls_features;

	return features;
}
#else
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
	return features;
}
#endif

2875
static netdev_features_t harmonize_features(struct sk_buff *skb,
2876
	netdev_features_t features)
2877
{
2878
	int tmp;
2879 2880 2881 2882
	__be16 type;

	type = skb_network_protocol(skb, &tmp);
	features = net_mpls_features(skb, features, type);
2883

2884
	if (skb->ip_summed != CHECKSUM_NONE &&
2885
	    !can_checksum_protocol(features, type)) {
2886
		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2887
	}
2888 2889
	if (illegal_highdma(skb->dev, skb))
		features &= ~NETIF_F_SG;
2890 2891 2892 2893

	return features;
}

2894 2895 2896 2897 2898 2899 2900 2901
netdev_features_t passthru_features_check(struct sk_buff *skb,
					  struct net_device *dev,
					  netdev_features_t features)
{
	return features;
}
EXPORT_SYMBOL(passthru_features_check);

2902 2903 2904 2905 2906 2907 2908
static netdev_features_t dflt_features_check(const struct sk_buff *skb,
					     struct net_device *dev,
					     netdev_features_t features)
{
	return vlan_features_check(skb, features);
}

2909 2910 2911 2912 2913 2914 2915 2916 2917
static netdev_features_t gso_features_check(const struct sk_buff *skb,
					    struct net_device *dev,
					    netdev_features_t features)
{
	u16 gso_segs = skb_shinfo(skb)->gso_segs;

	if (gso_segs > dev->gso_max_segs)
		return features & ~NETIF_F_GSO_MASK;

2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928
	/* Support for GSO partial features requires software
	 * intervention before we can actually process the packets
	 * so we need to strip support for any partial features now
	 * and we can pull them back in after we have partially
	 * segmented the frame.
	 */
	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
		features &= ~dev->gso_partial_features;

	/* Make sure to clear the IPv4 ID mangling feature if the
	 * IPv4 header has the potential to be fragmented.
2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940
	 */
	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
		struct iphdr *iph = skb->encapsulation ?
				    inner_ip_hdr(skb) : ip_hdr(skb);

		if (!(iph->frag_off & htons(IP_DF)))
			features &= ~NETIF_F_TSO_MANGLEID;
	}

	return features;
}

2941
netdev_features_t netif_skb_features(struct sk_buff *skb)
2942
{
2943
	struct net_device *dev = skb->dev;
2944
	netdev_features_t features = dev->features;
2945

2946 2947
	if (skb_is_gso(skb))
		features = gso_features_check(skb, dev, features);
2948

2949 2950 2951 2952 2953 2954 2955
	/* If encapsulation offload request, verify we are testing
	 * hardware encapsulation features instead of standard
	 * features for the netdev
	 */
	if (skb->encapsulation)
		features &= dev->hw_enc_features;

2956 2957 2958 2959 2960
	if (skb_vlan_tagged(skb))
		features = netdev_intersect_features(features,
						     dev->vlan_features |
						     NETIF_F_HW_VLAN_CTAG_TX |
						     NETIF_F_HW_VLAN_STAG_TX);
2961

2962 2963 2964
	if (dev->netdev_ops->ndo_features_check)
		features &= dev->netdev_ops->ndo_features_check(skb, dev,
								features);
2965 2966
	else
		features &= dflt_features_check(skb, dev, features);
2967

2968
	return harmonize_features(skb, features);
2969
}
2970
EXPORT_SYMBOL(netif_skb_features);
2971

2972
static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2973
		    struct netdev_queue *txq, bool more)
2974
{
2975 2976
	unsigned int len;
	int rc;
2977

2978
	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2979
		dev_queue_xmit_nit(skb, dev);
2980

2981 2982
	len = skb->len;
	trace_net_dev_start_xmit(skb, dev);
2983
	rc = netdev_start_xmit(skb, dev, txq, more);
2984
	trace_net_dev_xmit(skb, rc, dev, len);
E
Eric Dumazet 已提交
2985

2986 2987
	return rc;
}
2988

2989 2990
struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
				    struct netdev_queue *txq, int *ret)
2991 2992 2993
{
	struct sk_buff *skb = first;
	int rc = NETDEV_TX_OK;
2994

2995 2996
	while (skb) {
		struct sk_buff *next = skb->next;
2997

2998
		skb->next = NULL;
2999
		rc = xmit_one(skb, dev, txq, next != NULL);
3000 3001 3002 3003
		if (unlikely(!dev_xmit_complete(rc))) {
			skb->next = next;
			goto out;
		}
3004

3005 3006 3007 3008
		skb = next;
		if (netif_xmit_stopped(txq) && skb) {
			rc = NETDEV_TX_BUSY;
			break;
3009
		}
3010
	}
3011

3012 3013 3014 3015
out:
	*ret = rc;
	return skb;
}
3016

E
Eric Dumazet 已提交
3017 3018
static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
					  netdev_features_t features)
3019
{
3020
	if (skb_vlan_tag_present(skb) &&
3021 3022
	    !vlan_hw_offload_capable(features, skb->vlan_proto))
		skb = __vlan_hwaccel_push_inside(skb);
3023 3024
	return skb;
}
3025

3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036
int skb_csum_hwoffload_help(struct sk_buff *skb,
			    const netdev_features_t features)
{
	if (unlikely(skb->csum_not_inet))
		return !!(features & NETIF_F_SCTP_CRC) ? 0 :
			skb_crc32c_csum_help(skb);

	return !!(features & NETIF_F_CSUM_MASK) ? 0 : skb_checksum_help(skb);
}
EXPORT_SYMBOL(skb_csum_hwoffload_help);

3037
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
3038 3039
{
	netdev_features_t features;
3040

3041 3042 3043 3044
	features = netif_skb_features(skb);
	skb = validate_xmit_vlan(skb, features);
	if (unlikely(!skb))
		goto out_null;
3045

3046
	if (netif_needs_gso(skb, features)) {
3047 3048 3049
		struct sk_buff *segs;

		segs = skb_gso_segment(skb, features);
3050
		if (IS_ERR(segs)) {
3051
			goto out_kfree_skb;
3052 3053 3054
		} else if (segs) {
			consume_skb(skb);
			skb = segs;
3055
		}
3056 3057 3058 3059
	} else {
		if (skb_needs_linearize(skb, features) &&
		    __skb_linearize(skb))
			goto out_kfree_skb;
3060

3061 3062 3063
		if (validate_xmit_xfrm(skb, features))
			goto out_kfree_skb;

3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074
		/* If packet is not checksummed and device does not
		 * support checksumming for this protocol, complete
		 * checksumming here.
		 */
		if (skb->ip_summed == CHECKSUM_PARTIAL) {
			if (skb->encapsulation)
				skb_set_inner_transport_header(skb,
							       skb_checksum_start_offset(skb));
			else
				skb_set_transport_header(skb,
							 skb_checksum_start_offset(skb));
3075
			if (skb_csum_hwoffload_help(skb, features))
3076
				goto out_kfree_skb;
3077
		}
3078
	}
3079

3080
	return skb;
3081

3082 3083
out_kfree_skb:
	kfree_skb(skb);
3084
out_null:
E
Eric Dumazet 已提交
3085
	atomic_long_inc(&dev->tx_dropped);
3086 3087
	return NULL;
}
3088

3089 3090 3091 3092
struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
{
	struct sk_buff *next, *head = NULL, *tail;

3093
	for (; skb != NULL; skb = next) {
3094 3095
		next = skb->next;
		skb->next = NULL;
3096 3097 3098 3099

		/* in case skb wont be segmented, point to itself */
		skb->prev = skb;

3100
		skb = validate_xmit_skb(skb, dev);
3101 3102
		if (!skb)
			continue;
3103

3104 3105 3106 3107 3108 3109 3110 3111
		if (!head)
			head = skb;
		else
			tail->next = skb;
		/* If skb was segmented, skb->prev points to
		 * the last segment. If not, it still contains skb.
		 */
		tail = skb->prev;
3112 3113
	}
	return head;
3114
}
3115
EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
3116

3117 3118 3119 3120 3121 3122 3123 3124 3125 3126
static void qdisc_pkt_len_init(struct sk_buff *skb)
{
	const struct skb_shared_info *shinfo = skb_shinfo(skb);

	qdisc_skb_cb(skb)->pkt_len = skb->len;

	/* To get more precise estimation of bytes sent on wire,
	 * we add to pkt_len the headers size of all segments
	 */
	if (shinfo->gso_size)  {
3127
		unsigned int hdr_len;
3128
		u16 gso_segs = shinfo->gso_segs;
3129

3130 3131 3132 3133
		/* mac layer + network layer */
		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);

		/* + transport layer */
3134 3135 3136 3137
		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			hdr_len += tcp_hdrlen(skb);
		else
			hdr_len += sizeof(struct udphdr);
3138 3139 3140 3141 3142 3143

		if (shinfo->gso_type & SKB_GSO_DODGY)
			gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
						shinfo->gso_size);

		qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
3144 3145 3146
	}
}

3147 3148 3149 3150 3151
static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
				 struct net_device *dev,
				 struct netdev_queue *txq)
{
	spinlock_t *root_lock = qdisc_lock(q);
3152
	struct sk_buff *to_free = NULL;
E
Eric Dumazet 已提交
3153
	bool contended;
3154 3155
	int rc;

E
Eric Dumazet 已提交
3156
	qdisc_calculate_pkt_len(skb, q);
3157 3158 3159
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
3160
	 * This permits qdisc->running owner to get the lock more
Y
Ying Xue 已提交
3161
	 * often and dequeue packets faster.
3162
	 */
E
Eric Dumazet 已提交
3163
	contended = qdisc_is_running(q);
3164 3165 3166
	if (unlikely(contended))
		spin_lock(&q->busylock);

3167 3168
	spin_lock(root_lock);
	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3169
		__qdisc_drop(skb, &to_free);
3170 3171
		rc = NET_XMIT_DROP;
	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3172
		   qdisc_run_begin(q)) {
3173 3174 3175 3176 3177
		/*
		 * This is a work-conserving queue; there are no old skbs
		 * waiting to be sent out; and the qdisc is not running -
		 * xmit the skb directly.
		 */
3178 3179 3180

		qdisc_bstats_update(q, skb);

3181
		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
3182 3183 3184 3185
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
3186
			__qdisc_run(q);
3187
		} else
3188
			qdisc_run_end(q);
3189 3190 3191

		rc = NET_XMIT_SUCCESS;
	} else {
3192
		rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3193 3194 3195 3196 3197 3198 3199
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
3200 3201
	}
	spin_unlock(root_lock);
3202 3203
	if (unlikely(to_free))
		kfree_skb_list(to_free);
3204 3205
	if (unlikely(contended))
		spin_unlock(&q->busylock);
3206 3207 3208
	return rc;
}

3209
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3210 3211
static void skb_update_prio(struct sk_buff *skb)
{
I
Igor Maravic 已提交
3212
	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
3213

3214
	if (!skb->priority && skb->sk && map) {
3215 3216
		unsigned int prioidx =
			sock_cgroup_prioidx(&skb->sk->sk_cgrp_data);
3217 3218 3219 3220

		if (prioidx < map->priomap_len)
			skb->priority = map->priomap[prioidx];
	}
3221 3222 3223 3224 3225
}
#else
#define skb_update_prio(skb)
#endif

3226 3227 3228
DEFINE_PER_CPU(int, xmit_recursion);
EXPORT_SYMBOL(xmit_recursion);

3229 3230
/**
 *	dev_loopback_xmit - loop back @skb
3231 3232
 *	@net: network namespace this loopback is happening in
 *	@sk:  sk needed to be a netfilter okfn
3233 3234
 *	@skb: buffer to transmit
 */
3235
int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247
{
	skb_reset_mac_header(skb);
	__skb_pull(skb, skb_network_offset(skb));
	skb->pkt_type = PACKET_LOOPBACK;
	skb->ip_summed = CHECKSUM_UNNECESSARY;
	WARN_ON(!skb_dst(skb));
	skb_dst_force(skb);
	netif_rx_ni(skb);
	return 0;
}
EXPORT_SYMBOL(dev_loopback_xmit);

D
Daniel Borkmann 已提交
3248 3249 3250 3251 3252 3253 3254 3255 3256 3257
#ifdef CONFIG_NET_EGRESS
static struct sk_buff *
sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
{
	struct tcf_proto *cl = rcu_dereference_bh(dev->egress_cl_list);
	struct tcf_result cl_res;

	if (!cl)
		return skb;

3258
	/* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */
D
Daniel Borkmann 已提交
3259 3260
	qdisc_bstats_cpu_update(cl->q, skb);

3261
	switch (tcf_classify(skb, cl, &cl_res, false)) {
D
Daniel Borkmann 已提交
3262 3263 3264 3265 3266 3267 3268
	case TC_ACT_OK:
	case TC_ACT_RECLASSIFY:
		skb->tc_index = TC_H_MIN(cl_res.classid);
		break;
	case TC_ACT_SHOT:
		qdisc_qstats_cpu_drop(cl->q);
		*ret = NET_XMIT_DROP;
3269 3270
		kfree_skb(skb);
		return NULL;
D
Daniel Borkmann 已提交
3271 3272
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
3273
	case TC_ACT_TRAP:
D
Daniel Borkmann 已提交
3274
		*ret = NET_XMIT_SUCCESS;
3275
		consume_skb(skb);
D
Daniel Borkmann 已提交
3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289
		return NULL;
	case TC_ACT_REDIRECT:
		/* No need to push/pop skb's mac_header here on egress! */
		skb_do_redirect(skb);
		*ret = NET_XMIT_SUCCESS;
		return NULL;
	default:
		break;
	}

	return skb;
}
#endif /* CONFIG_NET_EGRESS */

3290 3291 3292 3293 3294 3295 3296 3297 3298 3299
static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
{
#ifdef CONFIG_XPS
	struct xps_dev_maps *dev_maps;
	struct xps_map *map;
	int queue_index = -1;

	rcu_read_lock();
	dev_maps = rcu_dereference(dev->xps_maps);
	if (dev_maps) {
3300 3301 3302 3303 3304 3305 3306 3307
		unsigned int tci = skb->sender_cpu - 1;

		if (dev->num_tc) {
			tci *= dev->num_tc;
			tci += netdev_get_prio_tc_map(dev, skb->priority);
		}

		map = rcu_dereference(dev_maps->cpu_map[tci]);
3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333
		if (map) {
			if (map->len == 1)
				queue_index = map->queues[0];
			else
				queue_index = map->queues[reciprocal_scale(skb_get_hash(skb),
									   map->len)];
			if (unlikely(queue_index >= dev->real_num_tx_queues))
				queue_index = -1;
		}
	}
	rcu_read_unlock();

	return queue_index;
#else
	return -1;
#endif
}

static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
	int queue_index = sk_tx_queue_get(sk);

	if (queue_index < 0 || skb->ooo_okay ||
	    queue_index >= dev->real_num_tx_queues) {
		int new_index = get_xps_queue(dev, skb);
3334

3335 3336 3337 3338
		if (new_index < 0)
			new_index = skb_tx_hash(dev, skb);

		if (queue_index != new_index && sk &&
3339
		    sk_fullsock(sk) &&
3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355
		    rcu_access_pointer(sk->sk_dst_cache))
			sk_tx_queue_set(sk, new_index);

		queue_index = new_index;
	}

	return queue_index;
}

struct netdev_queue *netdev_pick_tx(struct net_device *dev,
				    struct sk_buff *skb,
				    void *accel_priv)
{
	int queue_index = 0;

#ifdef CONFIG_XPS
3356 3357 3358
	u32 sender_cpu = skb->sender_cpu - 1;

	if (sender_cpu >= (u32)NR_CPUS)
3359 3360 3361 3362 3363
		skb->sender_cpu = raw_smp_processor_id() + 1;
#endif

	if (dev->real_num_tx_queues != 1) {
		const struct net_device_ops *ops = dev->netdev_ops;
3364

3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378
		if (ops->ndo_select_queue)
			queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
							    __netdev_pick_tx);
		else
			queue_index = __netdev_pick_tx(dev, skb);

		if (!accel_priv)
			queue_index = netdev_cap_txqueue(dev, queue_index);
	}

	skb_set_queue_mapping(skb, queue_index);
	return netdev_get_tx_queue(dev, queue_index);
}

3379
/**
3380
 *	__dev_queue_xmit - transmit a buffer
3381
 *	@skb: buffer to transmit
3382
 *	@accel_priv: private data used for L2 forwarding offload
3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404
 *
 *	Queue a buffer for transmission to a network device. The caller must
 *	have set the device and priority and built the buffer before calling
 *	this function. The function can be called from an interrupt.
 *
 *	A negative errno code is returned on a failure. A success does not
 *	guarantee the frame will be transmitted as it may be dropped due
 *	to congestion or traffic shaping.
 *
 * -----------------------------------------------------------------------------------
 *      I notice this method can also return errors from the queue disciplines,
 *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
 *      be positive.
 *
 *      Regardless of the return value, the skb is consumed, so it is currently
 *      difficult to retry a send to this method.  (You can bump the ref count
 *      before sending to hold a reference for retry if you are careful.)
 *
 *      When calling this method, interrupts MUST be enabled.  This is because
 *      the BH enable code must have IRQs enabled so that it will not deadlock.
 *          --BLG
 */
3405
static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
L
Linus Torvalds 已提交
3406 3407
{
	struct net_device *dev = skb->dev;
3408
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
3409 3410 3411
	struct Qdisc *q;
	int rc = -ENOMEM;

3412 3413
	skb_reset_mac_header(skb);

3414 3415 3416
	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);

3417 3418
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
3419
	 */
3420
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
3421

3422 3423
	skb_update_prio(skb);

D
Daniel Borkmann 已提交
3424 3425
	qdisc_pkt_len_init(skb);
#ifdef CONFIG_NET_CLS_ACT
3426
	skb->tc_at_ingress = 0;
D
Daniel Borkmann 已提交
3427 3428 3429 3430 3431 3432 3433 3434
# ifdef CONFIG_NET_EGRESS
	if (static_key_false(&egress_needed)) {
		skb = sch_handle_egress(skb, &rc, dev);
		if (!skb)
			goto out;
	}
# endif
#endif
3435 3436 3437 3438 3439 3440 3441 3442
	/* If device/qdisc don't need skb->dst, release it right now while
	 * its hot in this cpu cache.
	 */
	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
		skb_dst_drop(skb);
	else
		skb_dst_force(skb);

3443
	txq = netdev_pick_tx(dev, skb, accel_priv);
3444
	q = rcu_dereference_bh(txq->qdisc);
3445

3446
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
3447
	if (q->enqueue) {
3448
		rc = __dev_xmit_skb(skb, q, dev, txq);
3449
		goto out;
L
Linus Torvalds 已提交
3450 3451 3452
	}

	/* The device has no queue. Common case for software devices:
3453
	 * loopback, all the sorts of tunnels...
L
Linus Torvalds 已提交
3454

3455 3456 3457 3458 3459
	 * Really, it is unlikely that netif_tx_lock protection is necessary
	 * here.  (f.e. loopback and IP tunnels are clean ignoring statistics
	 * counters.)
	 * However, it is possible, that they rely on protection
	 * made by us here.
L
Linus Torvalds 已提交
3460

3461 3462
	 * Check this and shot the lock. It is not prone from deadlocks.
	 *Either shot noqueue qdisc, it is even simpler 8)
L
Linus Torvalds 已提交
3463 3464 3465 3466
	 */
	if (dev->flags & IFF_UP) {
		int cpu = smp_processor_id(); /* ok because BHs are off */

3467
		if (txq->xmit_lock_owner != cpu) {
3468 3469
			if (unlikely(__this_cpu_read(xmit_recursion) >
				     XMIT_RECURSION_LIMIT))
3470 3471
				goto recursion_alert;

3472 3473
			skb = validate_xmit_skb(skb, dev);
			if (!skb)
E
Eric Dumazet 已提交
3474
				goto out;
3475

3476
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
3477

3478
			if (!netif_xmit_stopped(txq)) {
3479
				__this_cpu_inc(xmit_recursion);
3480
				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3481
				__this_cpu_dec(xmit_recursion);
3482
				if (dev_xmit_complete(rc)) {
3483
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
3484 3485 3486
					goto out;
				}
			}
3487
			HARD_TX_UNLOCK(dev, txq);
3488 3489
			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
					     dev->name);
L
Linus Torvalds 已提交
3490 3491
		} else {
			/* Recursion is detected! It is possible,
3492 3493 3494
			 * unfortunately
			 */
recursion_alert:
3495 3496
			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
					     dev->name);
L
Linus Torvalds 已提交
3497 3498 3499 3500
		}
	}

	rc = -ENETDOWN;
3501
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3502

3503
	atomic_long_inc(&dev->tx_dropped);
3504
	kfree_skb_list(skb);
L
Linus Torvalds 已提交
3505 3506
	return rc;
out:
3507
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3508 3509
	return rc;
}
3510

3511
int dev_queue_xmit(struct sk_buff *skb)
3512 3513 3514
{
	return __dev_queue_xmit(skb, NULL);
}
3515
EXPORT_SYMBOL(dev_queue_xmit);
L
Linus Torvalds 已提交
3516

3517 3518 3519 3520 3521 3522
int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
{
	return __dev_queue_xmit(skb, accel_priv);
}
EXPORT_SYMBOL(dev_queue_xmit_accel);

L
Linus Torvalds 已提交
3523

3524 3525 3526
/*************************************************************************
 *			Receiver routines
 *************************************************************************/
L
Linus Torvalds 已提交
3527

3528
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
3529 3530
EXPORT_SYMBOL(netdev_max_backlog);

E
Eric Dumazet 已提交
3531
int netdev_tstamp_prequeue __read_mostly = 1;
3532
int netdev_budget __read_mostly = 300;
3533
unsigned int __read_mostly netdev_budget_usecs = 2000;
3534 3535 3536 3537 3538
int weight_p __read_mostly = 64;           /* old backlog weight */
int dev_weight_rx_bias __read_mostly = 1;  /* bias for backlog weight */
int dev_weight_tx_bias __read_mostly = 1;  /* bias for output_queue quota */
int dev_rx_weight __read_mostly = 64;
int dev_tx_weight __read_mostly = 64;
L
Linus Torvalds 已提交
3539

E
Eric Dumazet 已提交
3540 3541 3542 3543 3544 3545 3546 3547
/* Called with irq disabled */
static inline void ____napi_schedule(struct softnet_data *sd,
				     struct napi_struct *napi)
{
	list_add_tail(&napi->poll_list, &sd->poll_list);
	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
}

3548 3549 3550
#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
3551
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3552
EXPORT_SYMBOL(rps_sock_flow_table);
3553 3554
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
3555

3556
struct static_key rps_needed __read_mostly;
3557
EXPORT_SYMBOL(rps_needed);
E
Eric Dumazet 已提交
3558 3559
struct static_key rfs_needed __read_mostly;
EXPORT_SYMBOL(rfs_needed);
3560

3561 3562 3563 3564
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
3565
	if (next_cpu < nr_cpu_ids) {
3566 3567 3568 3569 3570 3571 3572 3573 3574
#ifdef CONFIG_RFS_ACCEL
		struct netdev_rx_queue *rxqueue;
		struct rps_dev_flow_table *flow_table;
		struct rps_dev_flow *old_rflow;
		u32 flow_id;
		u16 rxq_index;
		int rc;

		/* Should we steer this flow to a different hardware queue? */
3575 3576
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
3577 3578 3579 3580 3581 3582 3583 3584 3585
			goto out;
		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
		if (rxq_index == skb_get_rx_queue(skb))
			goto out;

		rxqueue = dev->_rx + rxq_index;
		flow_table = rcu_dereference(rxqueue->rps_flow_table);
		if (!flow_table)
			goto out;
3586
		flow_id = skb_get_hash(skb) & flow_table->mask;
3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598
		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
							rxq_index, flow_id);
		if (rc < 0)
			goto out;
		old_rflow = rflow;
		rflow = &flow_table->flows[flow_id];
		rflow->filter = rc;
		if (old_rflow->filter == rflow->filter)
			old_rflow->filter = RPS_NO_FILTER;
	out:
#endif
		rflow->last_qtail =
3599
			per_cpu(softnet_data, next_cpu).input_queue_head;
3600 3601
	}

3602
	rflow->cpu = next_cpu;
3603 3604 3605
	return rflow;
}

3606 3607 3608 3609 3610 3611 3612 3613
/*
 * get_rps_cpu is called from netif_receive_skb and returns the target
 * CPU from the RPS map of the receiving queue for a given skb.
 * rcu_read_lock must be held on entry.
 */
static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
		       struct rps_dev_flow **rflowp)
{
3614 3615
	const struct rps_sock_flow_table *sock_flow_table;
	struct netdev_rx_queue *rxqueue = dev->_rx;
3616
	struct rps_dev_flow_table *flow_table;
3617
	struct rps_map *map;
3618
	int cpu = -1;
3619
	u32 tcpu;
3620
	u32 hash;
3621 3622 3623

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
3624

3625 3626 3627 3628 3629
		if (unlikely(index >= dev->real_num_rx_queues)) {
			WARN_ONCE(dev->real_num_rx_queues > 1,
				  "%s received packet on queue %u, but number "
				  "of RX queues is %u\n",
				  dev->name, index, dev->real_num_rx_queues);
3630 3631
			goto done;
		}
3632 3633
		rxqueue += index;
	}
3634

3635 3636 3637
	/* Avoid computing hash if RFS/RPS is not active for this rxqueue */

	flow_table = rcu_dereference(rxqueue->rps_flow_table);
E
Eric Dumazet 已提交
3638
	map = rcu_dereference(rxqueue->rps_map);
3639
	if (!flow_table && !map)
3640 3641
		goto done;

3642
	skb_reset_network_header(skb);
3643 3644
	hash = skb_get_hash(skb);
	if (!hash)
3645 3646
		goto done;

T
Tom Herbert 已提交
3647 3648 3649
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		struct rps_dev_flow *rflow;
3650 3651 3652 3653 3654 3655 3656
		u32 next_cpu;
		u32 ident;

		/* First check into global flow table if there is a match */
		ident = sock_flow_table->ents[hash & sock_flow_table->mask];
		if ((ident ^ hash) & ~rps_cpu_mask)
			goto try_rps;
T
Tom Herbert 已提交
3657

3658 3659 3660 3661 3662
		next_cpu = ident & rps_cpu_mask;

		/* OK, now we know there is a match,
		 * we can look at the local (per receive queue) flow table
		 */
3663
		rflow = &flow_table->flows[hash & flow_table->mask];
T
Tom Herbert 已提交
3664 3665 3666 3667 3668 3669
		tcpu = rflow->cpu;

		/*
		 * If the desired CPU (where last recvmsg was done) is
		 * different from current CPU (one in the rx-queue flow
		 * table entry), switch if one of the following holds:
3670
		 *   - Current CPU is unset (>= nr_cpu_ids).
T
Tom Herbert 已提交
3671 3672 3673 3674 3675 3676 3677
		 *   - Current CPU is offline.
		 *   - The current CPU's queue tail has advanced beyond the
		 *     last packet that was enqueued using this table entry.
		 *     This guarantees that all previous packets for the flow
		 *     have been dequeued, thus preserving in order delivery.
		 */
		if (unlikely(tcpu != next_cpu) &&
3678
		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
T
Tom Herbert 已提交
3679
		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3680 3681
		      rflow->last_qtail)) >= 0)) {
			tcpu = next_cpu;
3682
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3683
		}
3684

3685
		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
T
Tom Herbert 已提交
3686 3687 3688 3689 3690 3691
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

3692 3693
try_rps:

T
Tom Herbert 已提交
3694
	if (map) {
3695
		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
T
Tom Herbert 已提交
3696 3697 3698 3699 3700 3701 3702 3703 3704 3705
		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725
#ifdef CONFIG_RFS_ACCEL

/**
 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
 * @dev: Device on which the filter was set
 * @rxq_index: RX queue index
 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
 *
 * Drivers that implement ndo_rx_flow_steer() should periodically call
 * this function for each installed filter and remove the filters for
 * which it returns %true.
 */
bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
			 u32 flow_id, u16 filter_id)
{
	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
	struct rps_dev_flow_table *flow_table;
	struct rps_dev_flow *rflow;
	bool expire = true;
3726
	unsigned int cpu;
3727 3728 3729 3730 3731 3732

	rcu_read_lock();
	flow_table = rcu_dereference(rxqueue->rps_flow_table);
	if (flow_table && flow_id <= flow_table->mask) {
		rflow = &flow_table->flows[flow_id];
		cpu = ACCESS_ONCE(rflow->cpu);
3733
		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745
		    ((int)(per_cpu(softnet_data, cpu).input_queue_head -
			   rflow->last_qtail) <
		     (int)(10 * flow_table->mask)))
			expire = false;
	}
	rcu_read_unlock();
	return expire;
}
EXPORT_SYMBOL(rps_may_expire_flow);

#endif /* CONFIG_RFS_ACCEL */

T
Tom Herbert 已提交
3746
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
3747
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
3748
{
E
Eric Dumazet 已提交
3749 3750
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
3751
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
3752
	sd->received_rps++;
T
Tom Herbert 已提交
3753
}
E
Eric Dumazet 已提交
3754

T
Tom Herbert 已提交
3755
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
3756

E
Eric Dumazet 已提交
3757 3758 3759 3760 3761 3762 3763 3764
/*
 * Check if this softnet_data structure is another cpu one
 * If yes, queue it to our IPI list and return 1
 * If no, return 0
 */
static int rps_ipi_queued(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
3765
	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
E
Eric Dumazet 已提交
3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777

	if (sd != mysd) {
		sd->rps_ipi_next = mysd->rps_ipi_list;
		mysd->rps_ipi_list = sd;

		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
		return 1;
	}
#endif /* CONFIG_RPS */
	return 0;
}

3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791
#ifdef CONFIG_NET_FLOW_LIMIT
int netdev_flow_limit_table_len __read_mostly = (1 << 12);
#endif

static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
{
#ifdef CONFIG_NET_FLOW_LIMIT
	struct sd_flow_limit *fl;
	struct softnet_data *sd;
	unsigned int old_flow, new_flow;

	if (qlen < (netdev_max_backlog >> 1))
		return false;

3792
	sd = this_cpu_ptr(&softnet_data);
3793 3794 3795 3796

	rcu_read_lock();
	fl = rcu_dereference(sd->flow_limit);
	if (fl) {
3797
		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817
		old_flow = fl->history[fl->history_head];
		fl->history[fl->history_head] = new_flow;

		fl->history_head++;
		fl->history_head &= FLOW_LIMIT_HISTORY - 1;

		if (likely(fl->buckets[old_flow]))
			fl->buckets[old_flow]--;

		if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
			fl->count++;
			rcu_read_unlock();
			return true;
		}
	}
	rcu_read_unlock();
#endif
	return false;
}

T
Tom Herbert 已提交
3818 3819 3820 3821
/*
 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
 * queue (may be a remote CPU queue).
 */
T
Tom Herbert 已提交
3822 3823
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
3824
{
E
Eric Dumazet 已提交
3825
	struct softnet_data *sd;
T
Tom Herbert 已提交
3826
	unsigned long flags;
3827
	unsigned int qlen;
T
Tom Herbert 已提交
3828

E
Eric Dumazet 已提交
3829
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
3830 3831 3832

	local_irq_save(flags);

E
Eric Dumazet 已提交
3833
	rps_lock(sd);
3834 3835
	if (!netif_running(skb->dev))
		goto drop;
3836 3837
	qlen = skb_queue_len(&sd->input_pkt_queue);
	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3838
		if (qlen) {
T
Tom Herbert 已提交
3839
enqueue:
E
Eric Dumazet 已提交
3840
			__skb_queue_tail(&sd->input_pkt_queue, skb);
3841
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
3842
			rps_unlock(sd);
3843
			local_irq_restore(flags);
T
Tom Herbert 已提交
3844 3845 3846
			return NET_RX_SUCCESS;
		}

3847 3848 3849 3850
		/* Schedule NAPI for backlog device
		 * We can use non atomic operation since we own the queue lock
		 */
		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
E
Eric Dumazet 已提交
3851
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
3852
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
3853 3854 3855 3856
		}
		goto enqueue;
	}

3857
drop:
C
Changli Gao 已提交
3858
	sd->dropped++;
E
Eric Dumazet 已提交
3859
	rps_unlock(sd);
T
Tom Herbert 已提交
3860 3861 3862

	local_irq_restore(flags);

3863
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
3864 3865 3866
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
3867

3868
static int netif_rx_internal(struct sk_buff *skb)
L
Linus Torvalds 已提交
3869
{
3870
	int ret;
L
Linus Torvalds 已提交
3871

3872
	net_timestamp_check(netdev_tstamp_prequeue, skb);
L
Linus Torvalds 已提交
3873

3874
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
3875
#ifdef CONFIG_RPS
3876
	if (static_key_false(&rps_needed)) {
T
Tom Herbert 已提交
3877
		struct rps_dev_flow voidflow, *rflow = &voidflow;
3878 3879
		int cpu;

3880
		preempt_disable();
3881
		rcu_read_lock();
T
Tom Herbert 已提交
3882 3883

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3884 3885
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
3886 3887 3888

		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);

3889
		rcu_read_unlock();
3890
		preempt_enable();
3891 3892
	} else
#endif
T
Tom Herbert 已提交
3893 3894
	{
		unsigned int qtail;
3895

T
Tom Herbert 已提交
3896 3897 3898
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
3899
	return ret;
L
Linus Torvalds 已提交
3900
}
3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922

/**
 *	netif_rx	-	post buffer to the network code
 *	@skb: buffer to post
 *
 *	This function receives a packet from a device driver and queues it for
 *	the upper (protocol) levels to process.  It always succeeds. The buffer
 *	may be dropped during processing for congestion control or by the
 *	protocol layers.
 *
 *	return values:
 *	NET_RX_SUCCESS	(no congestion)
 *	NET_RX_DROP     (packet was dropped)
 *
 */

int netif_rx(struct sk_buff *skb)
{
	trace_netif_rx_entry(skb);

	return netif_rx_internal(skb);
}
E
Eric Dumazet 已提交
3923
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
3924 3925 3926 3927 3928

int netif_rx_ni(struct sk_buff *skb)
{
	int err;

3929 3930
	trace_netif_rx_ni_entry(skb);

L
Linus Torvalds 已提交
3931
	preempt_disable();
3932
	err = netif_rx_internal(skb);
L
Linus Torvalds 已提交
3933 3934 3935 3936 3937 3938 3939 3940
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

3941
static __latent_entropy void net_tx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
3942
{
3943
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
L
Linus Torvalds 已提交
3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954

	if (sd->completion_queue) {
		struct sk_buff *clist;

		local_irq_disable();
		clist = sd->completion_queue;
		sd->completion_queue = NULL;
		local_irq_enable();

		while (clist) {
			struct sk_buff *skb = clist;
3955

L
Linus Torvalds 已提交
3956 3957
			clist = clist->next;

3958
			WARN_ON(refcount_read(&skb->users));
3959 3960 3961 3962
			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
				trace_consume_skb(skb);
			else
				trace_kfree_skb(skb, net_tx_action);
3963 3964 3965 3966 3967

			if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
				__kfree_skb(skb);
			else
				__kfree_skb_defer(skb);
L
Linus Torvalds 已提交
3968
		}
3969 3970

		__kfree_skb_flush();
L
Linus Torvalds 已提交
3971 3972 3973
	}

	if (sd->output_queue) {
3974
		struct Qdisc *head;
L
Linus Torvalds 已提交
3975 3976 3977 3978

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
3979
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
3980 3981 3982
		local_irq_enable();

		while (head) {
3983 3984 3985
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
3986 3987
			head = head->next_sched;

3988
			root_lock = qdisc_lock(q);
3989 3990 3991 3992 3993 3994 3995 3996
			spin_lock(root_lock);
			/* We need to make sure head->next_sched is read
			 * before clearing __QDISC_STATE_SCHED
			 */
			smp_mb__before_atomic();
			clear_bit(__QDISC_STATE_SCHED, &q->state);
			qdisc_run(q);
			spin_unlock(root_lock);
L
Linus Torvalds 已提交
3997 3998 3999 4000
		}
	}
}

4001
#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
4002 4003 4004
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
4005
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
4006
#endif
L
Linus Torvalds 已提交
4007

D
Daniel Borkmann 已提交
4008 4009 4010
static inline struct sk_buff *
sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
		   struct net_device *orig_dev)
4011
{
4012
#ifdef CONFIG_NET_CLS_ACT
4013 4014
	struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
	struct tcf_result cl_res;
4015

4016 4017 4018
	/* If there's at least one ingress present somewhere (so
	 * we get here via enabled static key), remaining devices
	 * that are not configured with an ingress qdisc will bail
4019
	 * out here.
4020
	 */
4021
	if (!cl)
4022
		return skb;
4023 4024 4025
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
4026 4027
	}

4028
	qdisc_skb_cb(skb)->pkt_len = skb->len;
4029
	skb->tc_at_ingress = 1;
4030
	qdisc_bstats_cpu_update(cl->q, skb);
4031

4032
	switch (tcf_classify(skb, cl, &cl_res, false)) {
4033 4034 4035 4036 4037
	case TC_ACT_OK:
	case TC_ACT_RECLASSIFY:
		skb->tc_index = TC_H_MIN(cl_res.classid);
		break;
	case TC_ACT_SHOT:
4038
		qdisc_qstats_cpu_drop(cl->q);
4039 4040
		kfree_skb(skb);
		return NULL;
4041 4042
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
4043
	case TC_ACT_TRAP:
4044
		consume_skb(skb);
4045
		return NULL;
4046 4047 4048 4049 4050 4051 4052 4053
	case TC_ACT_REDIRECT:
		/* skb_mac_header check was done by cls/act_bpf, so
		 * we can safely push the L2 header back before
		 * redirecting to another netdev
		 */
		__skb_push(skb, skb->mac_len);
		skb_do_redirect(skb);
		return NULL;
4054 4055
	default:
		break;
4056
	}
4057
#endif /* CONFIG_NET_CLS_ACT */
4058 4059
	return skb;
}
L
Linus Torvalds 已提交
4060

M
Mahesh Bandewar 已提交
4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076
/**
 *	netdev_is_rx_handler_busy - check if receive handler is registered
 *	@dev: device to check
 *
 *	Check if a receive handler is already registered for a given device.
 *	Return true if there one.
 *
 *	The caller must hold the rtnl_mutex.
 */
bool netdev_is_rx_handler_busy(struct net_device *dev)
{
	ASSERT_RTNL();
	return dev && rtnl_dereference(dev->rx_handler);
}
EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);

4077 4078 4079 4080
/**
 *	netdev_rx_handler_register - register receive handler
 *	@dev: device to register a handler for
 *	@rx_handler: receive handler to register
J
Jiri Pirko 已提交
4081
 *	@rx_handler_data: data pointer that is used by rx handler
4082
 *
4083
 *	Register a receive handler for a device. This handler will then be
4084 4085 4086 4087
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
4088 4089
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
4090 4091
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
4092 4093
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
4094
{
M
Mahesh Bandewar 已提交
4095
	if (netdev_is_rx_handler_busy(dev))
4096 4097
		return -EBUSY;

4098
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
4099
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
4100 4101 4102 4103 4104 4105 4106 4107 4108 4109
	rcu_assign_pointer(dev->rx_handler, rx_handler);

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_register);

/**
 *	netdev_rx_handler_unregister - unregister receive handler
 *	@dev: device to unregister a handler from
 *
K
Kusanagi Kouichi 已提交
4110
 *	Unregister a receive handler from a device.
4111 4112 4113 4114 4115 4116 4117
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
4118
	RCU_INIT_POINTER(dev->rx_handler, NULL);
4119 4120 4121 4122 4123
	/* a reader seeing a non NULL rx_handler in a rcu_read_lock()
	 * section has a guarantee to see a non NULL rx_handler_data
	 * as well.
	 */
	synchronize_net();
4124
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
4125 4126 4127
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

4128 4129 4130 4131 4132 4133 4134
/*
 * Limit the use of PFMEMALLOC reserves to those protocols that implement
 * the special handling of PFMEMALLOC skbs.
 */
static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
{
	switch (skb->protocol) {
4135 4136 4137 4138 4139
	case htons(ETH_P_ARP):
	case htons(ETH_P_IP):
	case htons(ETH_P_IPV6):
	case htons(ETH_P_8021Q):
	case htons(ETH_P_8021AD):
4140 4141 4142 4143 4144 4145
		return true;
	default:
		return false;
	}
}

4146 4147 4148
static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
			     int *ret, struct net_device *orig_dev)
{
4149
#ifdef CONFIG_NETFILTER_INGRESS
4150
	if (nf_hook_ingress_active(skb)) {
4151 4152
		int ingress_retval;

4153 4154 4155 4156 4157
		if (*pt_prev) {
			*ret = deliver_skb(skb, *pt_prev, orig_dev);
			*pt_prev = NULL;
		}

4158 4159 4160 4161
		rcu_read_lock();
		ingress_retval = nf_hook_ingress(skb);
		rcu_read_unlock();
		return ingress_retval;
4162
	}
4163
#endif /* CONFIG_NETFILTER_INGRESS */
4164 4165 4166
	return 0;
}

4167
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
4168 4169
{
	struct packet_type *ptype, *pt_prev;
4170
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
4171
	struct net_device *orig_dev;
4172
	bool deliver_exact = false;
L
Linus Torvalds 已提交
4173
	int ret = NET_RX_DROP;
A
Al Viro 已提交
4174
	__be16 type;
L
Linus Torvalds 已提交
4175

4176
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
4177

4178
	trace_netif_receive_skb(skb);
4179

J
Joe Eykholt 已提交
4180
	orig_dev = skb->dev;
4181

4182
	skb_reset_network_header(skb);
4183 4184
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
4185
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
4186 4187 4188

	pt_prev = NULL;

4189
another_round:
4190
	skb->skb_iif = skb->dev->ifindex;
4191 4192 4193

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
4194 4195
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
4196
		skb = skb_vlan_untag(skb);
4197
		if (unlikely(!skb))
4198
			goto out;
4199 4200
	}

4201 4202
	if (skb_skip_tc_classify(skb))
		goto skip_classify;
L
Linus Torvalds 已提交
4203

4204
	if (pfmemalloc)
4205 4206
		goto skip_taps;

L
Linus Torvalds 已提交
4207
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
4208 4209 4210 4211 4212 4213 4214 4215 4216
		if (pt_prev)
			ret = deliver_skb(skb, pt_prev, orig_dev);
		pt_prev = ptype;
	}

	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
		if (pt_prev)
			ret = deliver_skb(skb, pt_prev, orig_dev);
		pt_prev = ptype;
L
Linus Torvalds 已提交
4217 4218
	}

4219
skip_taps:
4220
#ifdef CONFIG_NET_INGRESS
4221
	if (static_key_false(&ingress_needed)) {
D
Daniel Borkmann 已提交
4222
		skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev);
4223
		if (!skb)
4224
			goto out;
4225 4226

		if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
4227
			goto out;
4228
	}
4229
#endif
4230
	skb_reset_tc(skb);
4231
skip_classify:
4232
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
4233 4234
		goto drop;

4235
	if (skb_vlan_tag_present(skb)) {
4236 4237 4238 4239
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4240
		if (vlan_do_receive(&skb))
4241 4242
			goto another_round;
		else if (unlikely(!skb))
4243
			goto out;
4244 4245
	}

4246
	rx_handler = rcu_dereference(skb->dev->rx_handler);
4247 4248 4249 4250 4251
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4252 4253
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
4254
			ret = NET_RX_SUCCESS;
4255
			goto out;
4256
		case RX_HANDLER_ANOTHER:
4257
			goto another_round;
4258 4259 4260 4261 4262 4263 4264
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
4265
	}
L
Linus Torvalds 已提交
4266

4267 4268
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
4269 4270 4271 4272 4273 4274 4275
			skb->pkt_type = PACKET_OTHERHOST;
		/* Note: we might in the future use prio bits
		 * and set skb->priority like in vlan_do_receive()
		 * For the time being, just ignore Priority Code Point
		 */
		skb->vlan_tci = 0;
	}
4276

4277 4278
	type = skb->protocol;

4279
	/* deliver only exact match when indicated */
4280 4281 4282 4283 4284
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
4285

4286 4287 4288 4289 4290 4291
	deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
			       &orig_dev->ptype_specific);

	if (unlikely(skb->dev != orig_dev)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &skb->dev->ptype_specific);
L
Linus Torvalds 已提交
4292 4293 4294
	}

	if (pt_prev) {
4295
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
4296
			goto drop;
4297 4298
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
4299
	} else {
4300
drop:
4301 4302 4303 4304
		if (!deliver_exact)
			atomic_long_inc(&skb->dev->rx_dropped);
		else
			atomic_long_inc(&skb->dev->rx_nohandler);
L
Linus Torvalds 已提交
4305 4306 4307 4308 4309 4310 4311
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

4312
out:
4313 4314 4315 4316 4317 4318 4319 4320
	return ret;
}

static int __netif_receive_skb(struct sk_buff *skb)
{
	int ret;

	if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
4321
		unsigned int noreclaim_flag;
4322 4323 4324 4325 4326 4327 4328 4329 4330 4331

		/*
		 * PFMEMALLOC skbs are special, they should
		 * - be delivered to SOCK_MEMALLOC sockets only
		 * - stay away from userspace
		 * - have bounded memory usage
		 *
		 * Use PF_MEMALLOC as this saves us from propagating the allocation
		 * context down to all allocation sites.
		 */
4332
		noreclaim_flag = memalloc_noreclaim_save();
4333
		ret = __netif_receive_skb_core(skb, true);
4334
		memalloc_noreclaim_restore(noreclaim_flag);
4335 4336 4337
	} else
		ret = __netif_receive_skb_core(skb, false);

L
Linus Torvalds 已提交
4338 4339
	return ret;
}
T
Tom Herbert 已提交
4340

D
David S. Miller 已提交
4341 4342 4343 4344
static struct static_key generic_xdp_needed __read_mostly;

static int generic_xdp_install(struct net_device *dev, struct netdev_xdp *xdp)
{
M
Martin KaFai Lau 已提交
4345
	struct bpf_prog *old = rtnl_dereference(dev->xdp_prog);
D
David S. Miller 已提交
4346 4347 4348 4349
	struct bpf_prog *new = xdp->prog;
	int ret = 0;

	switch (xdp->command) {
M
Martin KaFai Lau 已提交
4350
	case XDP_SETUP_PROG:
D
David S. Miller 已提交
4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363
		rcu_assign_pointer(dev->xdp_prog, new);
		if (old)
			bpf_prog_put(old);

		if (old && !new) {
			static_key_slow_dec(&generic_xdp_needed);
		} else if (new && !old) {
			static_key_slow_inc(&generic_xdp_needed);
			dev_disable_lro(dev);
		}
		break;

	case XDP_QUERY_PROG:
M
Martin KaFai Lau 已提交
4364 4365
		xdp->prog_attached = !!old;
		xdp->prog_id = old ? old->aux->id : 0;
D
David S. Miller 已提交
4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458
		break;

	default:
		ret = -EINVAL;
		break;
	}

	return ret;
}

static u32 netif_receive_generic_xdp(struct sk_buff *skb,
				     struct bpf_prog *xdp_prog)
{
	struct xdp_buff xdp;
	u32 act = XDP_DROP;
	void *orig_data;
	int hlen, off;
	u32 mac_len;

	/* Reinjected packets coming from act_mirred or similar should
	 * not get XDP generic processing.
	 */
	if (skb_cloned(skb))
		return XDP_PASS;

	if (skb_linearize(skb))
		goto do_drop;

	/* The XDP program wants to see the packet starting at the MAC
	 * header.
	 */
	mac_len = skb->data - skb_mac_header(skb);
	hlen = skb_headlen(skb) + mac_len;
	xdp.data = skb->data - mac_len;
	xdp.data_end = xdp.data + hlen;
	xdp.data_hard_start = skb->data - skb_headroom(skb);
	orig_data = xdp.data;

	act = bpf_prog_run_xdp(xdp_prog, &xdp);

	off = xdp.data - orig_data;
	if (off > 0)
		__skb_pull(skb, off);
	else if (off < 0)
		__skb_push(skb, -off);

	switch (act) {
	case XDP_TX:
		__skb_push(skb, mac_len);
		/* fall through */
	case XDP_PASS:
		break;

	default:
		bpf_warn_invalid_xdp_action(act);
		/* fall through */
	case XDP_ABORTED:
		trace_xdp_exception(skb->dev, xdp_prog, act);
		/* fall through */
	case XDP_DROP:
	do_drop:
		kfree_skb(skb);
		break;
	}

	return act;
}

/* When doing generic XDP we have to bypass the qdisc layer and the
 * network taps in order to match in-driver-XDP behavior.
 */
static void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
{
	struct net_device *dev = skb->dev;
	struct netdev_queue *txq;
	bool free_skb = true;
	int cpu, rc;

	txq = netdev_pick_tx(dev, skb, NULL);
	cpu = smp_processor_id();
	HARD_TX_LOCK(dev, txq, cpu);
	if (!netif_xmit_stopped(txq)) {
		rc = netdev_start_xmit(skb, dev, txq, 0);
		if (dev_xmit_complete(rc))
			free_skb = false;
	}
	HARD_TX_UNLOCK(dev, txq);
	if (free_skb) {
		trace_xdp_exception(dev, xdp_prog, XDP_TX);
		kfree_skb(skb);
	}
}

4459
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
4460
{
4461 4462
	int ret;

4463
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
4464

4465 4466 4467
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

4468 4469
	rcu_read_lock();

D
David S. Miller 已提交
4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484
	if (static_key_false(&generic_xdp_needed)) {
		struct bpf_prog *xdp_prog = rcu_dereference(skb->dev->xdp_prog);

		if (xdp_prog) {
			u32 act = netif_receive_generic_xdp(skb, xdp_prog);

			if (act != XDP_PASS) {
				rcu_read_unlock();
				if (act == XDP_TX)
					generic_xdp_tx(skb, xdp_prog);
				return NET_RX_DROP;
			}
		}
	}

E
Eric Dumazet 已提交
4485
#ifdef CONFIG_RPS
4486
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
4487
		struct rps_dev_flow voidflow, *rflow = &voidflow;
4488
		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
4489

E
Eric Dumazet 已提交
4490 4491 4492
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
4493
			return ret;
E
Eric Dumazet 已提交
4494
		}
T
Tom Herbert 已提交
4495
	}
4496
#endif
4497 4498 4499
	ret = __netif_receive_skb(skb);
	rcu_read_unlock();
	return ret;
T
Tom Herbert 已提交
4500
}
4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516

/**
 *	netif_receive_skb - process receive buffer from network
 *	@skb: buffer to process
 *
 *	netif_receive_skb() is the main receive data processing function.
 *	It always succeeds. The buffer may be dropped during processing
 *	for congestion control or by the protocol layers.
 *
 *	This function may only be called from softirq context and interrupts
 *	should be enabled.
 *
 *	Return values (usually ignored):
 *	NET_RX_SUCCESS: no congestion
 *	NET_RX_DROP: packet was dropped
 */
4517
int netif_receive_skb(struct sk_buff *skb)
4518 4519 4520 4521 4522
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
4523
EXPORT_SYMBOL(netif_receive_skb);
L
Linus Torvalds 已提交
4524

4525
DEFINE_PER_CPU(struct work_struct, flush_works);
4526 4527 4528

/* Network device is going away, flush any packets still pending */
static void flush_backlog(struct work_struct *work)
4529 4530
{
	struct sk_buff *skb, *tmp;
4531 4532 4533 4534
	struct softnet_data *sd;

	local_bh_disable();
	sd = this_cpu_ptr(&softnet_data);
4535

4536
	local_irq_disable();
E
Eric Dumazet 已提交
4537
	rps_lock(sd);
4538
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
4539
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
E
Eric Dumazet 已提交
4540
			__skb_unlink(skb, &sd->input_pkt_queue);
4541
			kfree_skb(skb);
4542
			input_queue_head_incr(sd);
4543
		}
4544
	}
E
Eric Dumazet 已提交
4545
	rps_unlock(sd);
4546
	local_irq_enable();
4547 4548

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
4549
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
4550 4551
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
4552
			input_queue_head_incr(sd);
4553 4554
		}
	}
4555 4556 4557
	local_bh_enable();
}

4558
static void flush_all_backlogs(void)
4559 4560 4561 4562 4563
{
	unsigned int cpu;

	get_online_cpus();

4564 4565 4566
	for_each_online_cpu(cpu)
		queue_work_on(cpu, system_highpri_wq,
			      per_cpu_ptr(&flush_works, cpu));
4567 4568

	for_each_online_cpu(cpu)
4569
		flush_work(per_cpu_ptr(&flush_works, cpu));
4570 4571

	put_online_cpus();
4572 4573
}

4574 4575
static int napi_gro_complete(struct sk_buff *skb)
{
4576
	struct packet_offload *ptype;
4577
	__be16 type = skb->protocol;
4578
	struct list_head *head = &offload_base;
4579 4580
	int err = -ENOENT;

4581 4582
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

4583 4584
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
4585
		goto out;
4586
	}
4587 4588 4589

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4590
		if (ptype->type != type || !ptype->callbacks.gro_complete)
4591 4592
			continue;

4593
		err = ptype->callbacks.gro_complete(skb, 0);
4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604
		break;
	}
	rcu_read_unlock();

	if (err) {
		WARN_ON(&ptype->list == head);
		kfree_skb(skb);
		return NET_RX_SUCCESS;
	}

out:
4605
	return netif_receive_skb_internal(skb);
4606 4607
}

4608 4609 4610 4611 4612
/* napi->gro_list contains packets ordered by age.
 * youngest packets at the head of it.
 * Complete skbs in reverse order to reduce latencies.
 */
void napi_gro_flush(struct napi_struct *napi, bool flush_old)
4613
{
4614
	struct sk_buff *skb, *prev = NULL;
4615

4616 4617 4618 4619 4620 4621 4622
	/* scan list and build reverse chain */
	for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
		skb->prev = prev;
		prev = skb;
	}

	for (skb = prev; skb; skb = prev) {
4623
		skb->next = NULL;
4624 4625 4626 4627 4628

		if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
			return;

		prev = skb->prev;
4629
		napi_gro_complete(skb);
4630
		napi->gro_count--;
4631 4632 4633 4634
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
4635
EXPORT_SYMBOL(napi_gro_flush);
4636

E
Eric Dumazet 已提交
4637 4638 4639 4640
static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
{
	struct sk_buff *p;
	unsigned int maclen = skb->dev->hard_header_len;
4641
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
4642 4643 4644 4645

	for (p = napi->gro_list; p; p = p->next) {
		unsigned long diffs;

4646 4647 4648 4649 4650 4651 4652
		NAPI_GRO_CB(p)->flush = 0;

		if (hash != skb_get_hash_raw(p)) {
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}

E
Eric Dumazet 已提交
4653 4654
		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
		diffs |= p->vlan_tci ^ skb->vlan_tci;
4655
		diffs |= skb_metadata_dst_cmp(p, skb);
E
Eric Dumazet 已提交
4656 4657
		if (maclen == ETH_HLEN)
			diffs |= compare_ether_header(skb_mac_header(p),
4658
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
4659 4660
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
4661
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
4662 4663 4664 4665 4666
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679
static void skb_gro_reset_offset(struct sk_buff *skb)
{
	const struct skb_shared_info *pinfo = skb_shinfo(skb);
	const skb_frag_t *frag0 = &pinfo->frags[0];

	NAPI_GRO_CB(skb)->data_offset = 0;
	NAPI_GRO_CB(skb)->frag0 = NULL;
	NAPI_GRO_CB(skb)->frag0_len = 0;

	if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
	    pinfo->nr_frags &&
	    !PageHighMem(skb_frag_page(frag0))) {
		NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
4680 4681 4682
		NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int,
						    skb_frag_size(frag0),
						    skb->end - skb->tail);
E
Eric Dumazet 已提交
4683 4684 4685
	}
}

4686 4687 4688 4689 4690 4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706
static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
{
	struct skb_shared_info *pinfo = skb_shinfo(skb);

	BUG_ON(skb->end - skb->tail < grow);

	memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);

	skb->data_len -= grow;
	skb->tail += grow;

	pinfo->frags[0].page_offset += grow;
	skb_frag_size_sub(&pinfo->frags[0], grow);

	if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
		skb_frag_unref(skb, 0);
		memmove(pinfo->frags, pinfo->frags + 1,
			--pinfo->nr_frags * sizeof(pinfo->frags[0]));
	}
}

R
Rami Rosen 已提交
4707
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4708 4709
{
	struct sk_buff **pp = NULL;
4710
	struct packet_offload *ptype;
4711
	__be16 type = skb->protocol;
4712
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
4713
	int same_flow;
4714
	enum gro_result ret;
4715
	int grow;
4716

D
David S. Miller 已提交
4717
	if (netif_elide_gro(skb->dev))
4718 4719
		goto normal;

E
Eric Dumazet 已提交
4720 4721
	gro_list_prepare(napi, skb);

4722 4723
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4724
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4725 4726
			continue;

4727
		skb_set_network_header(skb, skb_gro_offset(skb));
4728
		skb_reset_mac_len(skb);
4729
		NAPI_GRO_CB(skb)->same_flow = 0;
E
Eric Dumazet 已提交
4730
		NAPI_GRO_CB(skb)->flush = skb_is_gso(skb) || skb_has_frag_list(skb);
H
Herbert Xu 已提交
4731
		NAPI_GRO_CB(skb)->free = 0;
4732
		NAPI_GRO_CB(skb)->encap_mark = 0;
S
Sabrina Dubroca 已提交
4733
		NAPI_GRO_CB(skb)->recursion_counter = 0;
4734
		NAPI_GRO_CB(skb)->is_fou = 0;
4735
		NAPI_GRO_CB(skb)->is_atomic = 1;
4736
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4737

4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752
		/* Setup for GRO checksum validation */
		switch (skb->ip_summed) {
		case CHECKSUM_COMPLETE:
			NAPI_GRO_CB(skb)->csum = skb->csum;
			NAPI_GRO_CB(skb)->csum_valid = 1;
			NAPI_GRO_CB(skb)->csum_cnt = 0;
			break;
		case CHECKSUM_UNNECESSARY:
			NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
			NAPI_GRO_CB(skb)->csum_valid = 0;
			break;
		default:
			NAPI_GRO_CB(skb)->csum_cnt = 0;
			NAPI_GRO_CB(skb)->csum_valid = 0;
		}
4753

4754
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4755 4756 4757 4758 4759 4760 4761
		break;
	}
	rcu_read_unlock();

	if (&ptype->list == head)
		goto normal;

4762 4763 4764 4765 4766
	if (IS_ERR(pp) && PTR_ERR(pp) == -EINPROGRESS) {
		ret = GRO_CONSUMED;
		goto ok;
	}

H
Herbert Xu 已提交
4767
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4768
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4769

4770 4771 4772 4773 4774 4775
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4776
		napi->gro_count--;
4777 4778
	}

H
Herbert Xu 已提交
4779
	if (same_flow)
4780 4781
		goto ok;

4782
	if (NAPI_GRO_CB(skb)->flush)
4783 4784
		goto normal;

4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798
	if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
		struct sk_buff *nskb = napi->gro_list;

		/* locate the end of the list to select the 'oldest' flow */
		while (nskb->next) {
			pp = &nskb->next;
			nskb = *pp;
		}
		*pp = NULL;
		nskb->next = NULL;
		napi_gro_complete(nskb);
	} else {
		napi->gro_count++;
	}
4799
	NAPI_GRO_CB(skb)->count = 1;
4800
	NAPI_GRO_CB(skb)->age = jiffies;
4801
	NAPI_GRO_CB(skb)->last = skb;
4802
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4803 4804
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4805
	ret = GRO_HELD;
4806

4807
pull:
4808 4809 4810
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4811
ok:
4812
	return ret;
4813 4814

normal:
4815 4816
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4817
}
4818

4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830
struct packet_offload *gro_find_receive_by_type(__be16 type)
{
	struct list_head *offload_head = &offload_base;
	struct packet_offload *ptype;

	list_for_each_entry_rcu(ptype, offload_head, list) {
		if (ptype->type != type || !ptype->callbacks.gro_receive)
			continue;
		return ptype;
	}
	return NULL;
}
4831
EXPORT_SYMBOL(gro_find_receive_by_type);
4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844

struct packet_offload *gro_find_complete_by_type(__be16 type)
{
	struct list_head *offload_head = &offload_base;
	struct packet_offload *ptype;

	list_for_each_entry_rcu(ptype, offload_head, list) {
		if (ptype->type != type || !ptype->callbacks.gro_complete)
			continue;
		return ptype;
	}
	return NULL;
}
4845
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4846

4847 4848 4849 4850 4851 4852 4853
static void napi_skb_free_stolen_head(struct sk_buff *skb)
{
	skb_dst_drop(skb);
	secpath_reset(skb);
	kmem_cache_free(skbuff_head_cache, skb);
}

R
Rami Rosen 已提交
4854
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4855
{
4856 4857
	switch (ret) {
	case GRO_NORMAL:
4858
		if (netif_receive_skb_internal(skb))
4859 4860
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4861

4862
	case GRO_DROP:
H
Herbert Xu 已提交
4863 4864
		kfree_skb(skb);
		break;
4865

4866
	case GRO_MERGED_FREE:
4867 4868 4869
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
			napi_skb_free_stolen_head(skb);
		else
4870
			__kfree_skb(skb);
4871 4872
		break;

4873 4874
	case GRO_HELD:
	case GRO_MERGED:
4875
	case GRO_CONSUMED:
4876
		break;
H
Herbert Xu 已提交
4877 4878
	}

4879
	return ret;
4880 4881
}

4882
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4883
{
4884
	skb_mark_napi_id(skb, napi);
4885
	trace_napi_gro_receive_entry(skb);
4886

4887 4888
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4889
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4890 4891 4892
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4893
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4894
{
4895 4896 4897 4898
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4899
	__skb_pull(skb, skb_headlen(skb));
4900 4901
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4902
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4903
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4904
	skb->skb_iif = 0;
4905 4906
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4907
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4908
	secpath_reset(skb);
4909 4910 4911 4912

	napi->skb = skb;
}

4913
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4914 4915 4916 4917
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4918
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
4919 4920 4921 4922
		if (skb) {
			napi->skb = skb;
			skb_mark_napi_id(skb, napi);
		}
4923
	}
4924 4925
	return skb;
}
4926
EXPORT_SYMBOL(napi_get_frags);
4927

4928 4929 4930
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4931
{
4932 4933
	switch (ret) {
	case GRO_NORMAL:
4934 4935 4936 4937
	case GRO_HELD:
		__skb_push(skb, ETH_HLEN);
		skb->protocol = eth_type_trans(skb, skb->dev);
		if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4938
			ret = GRO_DROP;
4939
		break;
H
Herbert Xu 已提交
4940

4941 4942 4943
	case GRO_DROP:
		napi_reuse_skb(napi, skb);
		break;
4944

4945 4946 4947 4948 4949 4950 4951
	case GRO_MERGED_FREE:
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
			napi_skb_free_stolen_head(skb);
		else
			napi_reuse_skb(napi, skb);
		break;

4952
	case GRO_MERGED:
4953
	case GRO_CONSUMED:
4954
		break;
4955
	}
H
Herbert Xu 已提交
4956

4957
	return ret;
H
Herbert Xu 已提交
4958
}
4959

4960 4961 4962 4963
/* Upper GRO stack assumes network header starts at gro_offset=0
 * Drivers could call both napi_gro_frags() and napi_gro_receive()
 * We copy ethernet header into skb->data to have a common layout.
 */
E
Eric Dumazet 已提交
4964
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4965 4966
{
	struct sk_buff *skb = napi->skb;
4967 4968
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4969 4970 4971

	napi->skb = NULL;

4972 4973 4974 4975 4976 4977 4978
	skb_reset_mac_header(skb);
	skb_gro_reset_offset(skb);

	eth = skb_gro_header_fast(skb, 0);
	if (unlikely(skb_gro_header_hard(skb, hlen))) {
		eth = skb_gro_header_slow(skb, hlen, 0);
		if (unlikely(!eth)) {
4979 4980
			net_warn_ratelimited("%s: dropping impossible skb from %s\n",
					     __func__, napi->dev->name);
4981 4982 4983 4984 4985 4986 4987
			napi_reuse_skb(napi, skb);
			return NULL;
		}
	} else {
		gro_pull_from_frag0(skb, hlen);
		NAPI_GRO_CB(skb)->frag0 += hlen;
		NAPI_GRO_CB(skb)->frag0_len -= hlen;
4988
	}
4989 4990 4991 4992 4993 4994 4995 4996
	__skb_pull(skb, hlen);

	/*
	 * This works because the only protocols we care about don't require
	 * special handling.
	 * We'll fix it up properly in napi_frags_finish()
	 */
	skb->protocol = eth->h_proto;
4997 4998 4999 5000

	return skb;
}

5001
gro_result_t napi_gro_frags(struct napi_struct *napi)
5002
{
5003
	struct sk_buff *skb = napi_frags_skb(napi);
5004 5005

	if (!skb)
5006
		return GRO_DROP;
5007

5008 5009
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
5010
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
5011
}
H
Herbert Xu 已提交
5012 5013
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038
/* Compute the checksum from gro_offset and return the folded value
 * after adding in any pseudo checksum.
 */
__sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
{
	__wsum wsum;
	__sum16 sum;

	wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);

	/* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
	sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
	if (likely(!sum)) {
		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
		    !skb->csum_complete_sw)
			netdev_rx_csum_fault(skb->dev);
	}

	NAPI_GRO_CB(skb)->csum = wsum;
	NAPI_GRO_CB(skb)->csum_valid = 1;

	return sum;
}
EXPORT_SYMBOL(__skb_gro_checksum_complete);

5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051
static void net_rps_send_ipi(struct softnet_data *remsd)
{
#ifdef CONFIG_RPS
	while (remsd) {
		struct softnet_data *next = remsd->rps_ipi_next;

		if (cpu_online(remsd->cpu))
			smp_call_function_single_async(remsd->cpu, &remsd->csd);
		remsd = next;
	}
#endif
}

5052
/*
5053
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066
 * Note: called with local irq disabled, but exits with local irq enabled.
 */
static void net_rps_action_and_irq_enable(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	struct softnet_data *remsd = sd->rps_ipi_list;

	if (remsd) {
		sd->rps_ipi_list = NULL;

		local_irq_enable();

		/* Send pending IPI's to kick RPS processing on remote cpus. */
5067
		net_rps_send_ipi(remsd);
5068 5069 5070 5071 5072
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
5073 5074 5075 5076 5077 5078 5079 5080 5081
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

5082
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
5083
{
E
Eric Dumazet 已提交
5084
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
5085 5086
	bool again = true;
	int work = 0;
L
Linus Torvalds 已提交
5087

5088 5089 5090
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
5091
	if (sd_has_rps_ipi_waiting(sd)) {
5092 5093 5094
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
5095

5096
	napi->weight = dev_rx_weight;
5097
	while (again) {
L
Linus Torvalds 已提交
5098
		struct sk_buff *skb;
5099 5100

		while ((skb = __skb_dequeue(&sd->process_queue))) {
5101
			rcu_read_lock();
5102
			__netif_receive_skb(skb);
5103
			rcu_read_unlock();
5104
			input_queue_head_incr(sd);
5105
			if (++work >= quota)
5106
				return work;
5107

5108
		}
L
Linus Torvalds 已提交
5109

5110
		local_irq_disable();
E
Eric Dumazet 已提交
5111
		rps_lock(sd);
5112
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
5113 5114 5115
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
5116 5117 5118
			 * and NAPI_STATE_SCHED is the only possible flag set
			 * on backlog.
			 * We can use a plain write instead of clear_bit(),
E
Eric Dumazet 已提交
5119 5120 5121
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
5122 5123 5124 5125
			again = false;
		} else {
			skb_queue_splice_tail_init(&sd->input_pkt_queue,
						   &sd->process_queue);
5126
		}
E
Eric Dumazet 已提交
5127
		rps_unlock(sd);
5128
		local_irq_enable();
5129
	}
L
Linus Torvalds 已提交
5130

5131 5132
	return work;
}
L
Linus Torvalds 已提交
5133

5134 5135
/**
 * __napi_schedule - schedule for receive
5136
 * @n: entry to schedule
5137
 *
5138 5139
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
5140
 */
H
Harvey Harrison 已提交
5141
void __napi_schedule(struct napi_struct *n)
5142 5143
{
	unsigned long flags;
L
Linus Torvalds 已提交
5144

5145
	local_irq_save(flags);
5146
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
5147
	local_irq_restore(flags);
L
Linus Torvalds 已提交
5148
}
5149 5150
EXPORT_SYMBOL(__napi_schedule);

E
Eric Dumazet 已提交
5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183
/**
 *	napi_schedule_prep - check if napi can be scheduled
 *	@n: napi context
 *
 * Test if NAPI routine is already running, and if not mark
 * it as running.  This is used as a condition variable
 * insure only one NAPI poll instance runs.  We also make
 * sure there is no pending NAPI disable.
 */
bool napi_schedule_prep(struct napi_struct *n)
{
	unsigned long val, new;

	do {
		val = READ_ONCE(n->state);
		if (unlikely(val & NAPIF_STATE_DISABLE))
			return false;
		new = val | NAPIF_STATE_SCHED;

		/* Sets STATE_MISSED bit if STATE_SCHED was already set
		 * This was suggested by Alexander Duyck, as compiler
		 * emits better code than :
		 * if (val & NAPIF_STATE_SCHED)
		 *     new |= NAPIF_STATE_MISSED;
		 */
		new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
						   NAPIF_STATE_MISSED;
	} while (cmpxchg(&n->state, val, new) != val);

	return !(val & NAPIF_STATE_SCHED);
}
EXPORT_SYMBOL(napi_schedule_prep);

5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195
/**
 * __napi_schedule_irqoff - schedule for receive
 * @n: entry to schedule
 *
 * Variant of __napi_schedule() assuming hard irqs are masked
 */
void __napi_schedule_irqoff(struct napi_struct *n)
{
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
}
EXPORT_SYMBOL(__napi_schedule_irqoff);

5196
bool napi_complete_done(struct napi_struct *n, int work_done)
5197
{
E
Eric Dumazet 已提交
5198
	unsigned long flags, val, new;
5199 5200

	/*
5201 5202 5203 5204
	 * 1) Don't let napi dequeue from the cpu poll list
	 *    just in case its running on a different cpu.
	 * 2) If we are busy polling, do nothing here, we have
	 *    the guarantee we will be called later.
5205
	 */
5206 5207
	if (unlikely(n->state & (NAPIF_STATE_NPSVC |
				 NAPIF_STATE_IN_BUSY_POLL)))
5208
		return false;
5209

5210 5211
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
5212

5213 5214 5215 5216 5217 5218 5219 5220 5221
		if (work_done)
			timeout = n->dev->gro_flush_timeout;

		if (timeout)
			hrtimer_start(&n->timer, ns_to_ktime(timeout),
				      HRTIMER_MODE_REL_PINNED);
		else
			napi_gro_flush(n, false);
	}
E
Eric Dumazet 已提交
5222
	if (unlikely(!list_empty(&n->poll_list))) {
E
Eric Dumazet 已提交
5223 5224
		/* If n->poll_list is not empty, we need to mask irqs */
		local_irq_save(flags);
E
Eric Dumazet 已提交
5225
		list_del_init(&n->poll_list);
E
Eric Dumazet 已提交
5226 5227
		local_irq_restore(flags);
	}
E
Eric Dumazet 已提交
5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248

	do {
		val = READ_ONCE(n->state);

		WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));

		new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED);

		/* If STATE_MISSED was set, leave STATE_SCHED set,
		 * because we will call napi->poll() one more time.
		 * This C code was suggested by Alexander Duyck to help gcc.
		 */
		new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
						    NAPIF_STATE_SCHED;
	} while (cmpxchg(&n->state, val, new) != val);

	if (unlikely(val & NAPIF_STATE_MISSED)) {
		__napi_schedule(n);
		return false;
	}

5249
	return true;
5250
}
5251
EXPORT_SYMBOL(napi_complete_done);
5252

E
Eliezer Tamir 已提交
5253
/* must be called under rcu_read_lock(), as we dont take a reference */
E
Eric Dumazet 已提交
5254
static struct napi_struct *napi_by_id(unsigned int napi_id)
E
Eliezer Tamir 已提交
5255 5256 5257 5258 5259 5260 5261 5262 5263 5264
{
	unsigned int hash = napi_id % HASH_SIZE(napi_hash);
	struct napi_struct *napi;

	hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
		if (napi->napi_id == napi_id)
			return napi;

	return NULL;
}
E
Eric Dumazet 已提交
5265 5266

#if defined(CONFIG_NET_RX_BUSY_POLL)
5267

5268
#define BUSY_POLL_BUDGET 8
5269 5270 5271 5272 5273

static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock)
{
	int rc;

E
Eric Dumazet 已提交
5274 5275 5276 5277 5278 5279 5280 5281 5282 5283
	/* Busy polling means there is a high chance device driver hard irq
	 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was
	 * set in napi_schedule_prep().
	 * Since we are about to call napi->poll() once more, we can safely
	 * clear NAPI_STATE_MISSED.
	 *
	 * Note: x86 could use a single "lock and ..." instruction
	 * to perform these two clear_bit()
	 */
	clear_bit(NAPI_STATE_MISSED, &napi->state);
5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297
	clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state);

	local_bh_disable();

	/* All we really want here is to re-enable device interrupts.
	 * Ideally, a new ndo_busy_poll_stop() could avoid another round.
	 */
	rc = napi->poll(napi, BUSY_POLL_BUDGET);
	netpoll_poll_unlock(have_poll_lock);
	if (rc == BUSY_POLL_BUDGET)
		__napi_schedule(napi);
	local_bh_enable();
}

5298 5299 5300
void napi_busy_loop(unsigned int napi_id,
		    bool (*loop_end)(void *, unsigned long),
		    void *loop_end_arg)
E
Eric Dumazet 已提交
5301
{
5302
	unsigned long start_time = loop_end ? busy_loop_current_time() : 0;
5303 5304
	int (*napi_poll)(struct napi_struct *napi, int budget);
	void *have_poll_lock = NULL;
E
Eric Dumazet 已提交
5305
	struct napi_struct *napi;
5306 5307 5308

restart:
	napi_poll = NULL;
E
Eric Dumazet 已提交
5309

5310
	rcu_read_lock();
E
Eric Dumazet 已提交
5311

5312
	napi = napi_by_id(napi_id);
E
Eric Dumazet 已提交
5313 5314 5315
	if (!napi)
		goto out;

5316 5317
	preempt_disable();
	for (;;) {
5318 5319
		int work = 0;

5320
		local_bh_disable();
5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336
		if (!napi_poll) {
			unsigned long val = READ_ONCE(napi->state);

			/* If multiple threads are competing for this napi,
			 * we avoid dirtying napi->state as much as we can.
			 */
			if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED |
				   NAPIF_STATE_IN_BUSY_POLL))
				goto count;
			if (cmpxchg(&napi->state, val,
				    val | NAPIF_STATE_IN_BUSY_POLL |
					  NAPIF_STATE_SCHED) != val)
				goto count;
			have_poll_lock = netpoll_poll_lock(napi);
			napi_poll = napi->poll;
		}
5337 5338
		work = napi_poll(napi, BUSY_POLL_BUDGET);
		trace_napi_poll(napi, work, BUSY_POLL_BUDGET);
5339
count:
5340
		if (work > 0)
5341
			__NET_ADD_STATS(dev_net(napi->dev),
5342
					LINUX_MIB_BUSYPOLLRXPACKETS, work);
5343
		local_bh_enable();
E
Eric Dumazet 已提交
5344

5345
		if (!loop_end || loop_end(loop_end_arg, start_time))
5346
			break;
E
Eric Dumazet 已提交
5347

5348 5349 5350 5351 5352 5353
		if (unlikely(need_resched())) {
			if (napi_poll)
				busy_poll_stop(napi, have_poll_lock);
			preempt_enable();
			rcu_read_unlock();
			cond_resched();
5354
			if (loop_end(loop_end_arg, start_time))
5355
				return;
5356 5357
			goto restart;
		}
5358
		cpu_relax();
5359 5360 5361 5362
	}
	if (napi_poll)
		busy_poll_stop(napi, have_poll_lock);
	preempt_enable();
E
Eric Dumazet 已提交
5363
out:
5364
	rcu_read_unlock();
E
Eric Dumazet 已提交
5365
}
5366
EXPORT_SYMBOL(napi_busy_loop);
E
Eric Dumazet 已提交
5367 5368

#endif /* CONFIG_NET_RX_BUSY_POLL */
E
Eliezer Tamir 已提交
5369

5370
static void napi_hash_add(struct napi_struct *napi)
E
Eliezer Tamir 已提交
5371
{
E
Eric Dumazet 已提交
5372 5373
	if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) ||
	    test_and_set_bit(NAPI_STATE_HASHED, &napi->state))
5374
		return;
E
Eliezer Tamir 已提交
5375

5376
	spin_lock(&napi_hash_lock);
E
Eliezer Tamir 已提交
5377

5378
	/* 0..NR_CPUS range is reserved for sender_cpu use */
5379
	do {
5380 5381
		if (unlikely(++napi_gen_id < MIN_NAPI_ID))
			napi_gen_id = MIN_NAPI_ID;
5382 5383
	} while (napi_by_id(napi_gen_id));
	napi->napi_id = napi_gen_id;
E
Eliezer Tamir 已提交
5384

5385 5386
	hlist_add_head_rcu(&napi->napi_hash_node,
			   &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
E
Eliezer Tamir 已提交
5387

5388
	spin_unlock(&napi_hash_lock);
E
Eliezer Tamir 已提交
5389 5390 5391 5392 5393
}

/* Warning : caller is responsible to make sure rcu grace period
 * is respected before freeing memory containing @napi
 */
5394
bool napi_hash_del(struct napi_struct *napi)
E
Eliezer Tamir 已提交
5395
{
5396 5397
	bool rcu_sync_needed = false;

E
Eliezer Tamir 已提交
5398 5399
	spin_lock(&napi_hash_lock);

5400 5401
	if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) {
		rcu_sync_needed = true;
E
Eliezer Tamir 已提交
5402
		hlist_del_rcu(&napi->napi_hash_node);
5403
	}
E
Eliezer Tamir 已提交
5404
	spin_unlock(&napi_hash_lock);
5405
	return rcu_sync_needed;
E
Eliezer Tamir 已提交
5406 5407 5408
}
EXPORT_SYMBOL_GPL(napi_hash_del);

5409 5410 5411 5412 5413
static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
{
	struct napi_struct *napi;

	napi = container_of(timer, struct napi_struct, timer);
E
Eric Dumazet 已提交
5414 5415 5416 5417 5418 5419 5420

	/* Note : we use a relaxed variant of napi_schedule_prep() not setting
	 * NAPI_STATE_MISSED, since we do not react to a device IRQ.
	 */
	if (napi->gro_list && !napi_disable_pending(napi) &&
	    !test_and_set_bit(NAPI_STATE_SCHED, &napi->state))
		__napi_schedule_irqoff(napi);
5421 5422 5423 5424

	return HRTIMER_NORESTART;
}

5425 5426 5427 5428
void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
		    int (*poll)(struct napi_struct *, int), int weight)
{
	INIT_LIST_HEAD(&napi->poll_list);
5429 5430
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
5431
	napi->gro_count = 0;
5432
	napi->gro_list = NULL;
H
Herbert Xu 已提交
5433
	napi->skb = NULL;
5434
	napi->poll = poll;
E
Eric Dumazet 已提交
5435 5436 5437
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
5438 5439 5440
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
5441
#ifdef CONFIG_NETPOLL
5442 5443 5444
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
5445
	napi_hash_add(napi);
5446 5447 5448
}
EXPORT_SYMBOL(netif_napi_add);

5449 5450 5451 5452 5453 5454 5455
void napi_disable(struct napi_struct *n)
{
	might_sleep();
	set_bit(NAPI_STATE_DISABLE, &n->state);

	while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
		msleep(1);
5456 5457
	while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
		msleep(1);
5458 5459 5460 5461 5462 5463 5464

	hrtimer_cancel(&n->timer);

	clear_bit(NAPI_STATE_DISABLE, &n->state);
}
EXPORT_SYMBOL(napi_disable);

5465
/* Must be called in process context */
5466 5467
void netif_napi_del(struct napi_struct *napi)
{
5468 5469 5470
	might_sleep();
	if (napi_hash_del(napi))
		synchronize_net();
5471
	list_del_init(&napi->dev_list);
5472
	napi_free_frags(napi);
5473

E
Eric Dumazet 已提交
5474
	kfree_skb_list(napi->gro_list);
5475
	napi->gro_list = NULL;
5476
	napi->gro_count = 0;
5477 5478 5479
}
EXPORT_SYMBOL(netif_napi_del);

5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499
static int napi_poll(struct napi_struct *n, struct list_head *repoll)
{
	void *have;
	int work, weight;

	list_del_init(&n->poll_list);

	have = netpoll_poll_lock(n);

	weight = n->weight;

	/* This NAPI_STATE_SCHED test is for avoiding a race
	 * with netpoll's poll_napi().  Only the entity which
	 * obtains the lock and sees NAPI_STATE_SCHED set will
	 * actually make the ->poll() call.  Therefore we avoid
	 * accidentally calling ->poll() when NAPI is not scheduled.
	 */
	work = 0;
	if (test_bit(NAPI_STATE_SCHED, &n->state)) {
		work = n->poll(n, weight);
5500
		trace_napi_poll(n, work, weight);
5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524
	}

	WARN_ON_ONCE(work > weight);

	if (likely(work < weight))
		goto out_unlock;

	/* Drivers must not modify the NAPI state if they
	 * consume the entire weight.  In such cases this code
	 * still "owns" the NAPI instance and therefore can
	 * move the instance around on the list at-will.
	 */
	if (unlikely(napi_disable_pending(n))) {
		napi_complete(n);
		goto out_unlock;
	}

	if (n->gro_list) {
		/* flush too old packets
		 * If HZ < 1000, flush all packets.
		 */
		napi_gro_flush(n, HZ >= 1000);
	}

5525 5526 5527 5528 5529 5530 5531 5532 5533
	/* Some drivers may have called napi_schedule
	 * prior to exhausting their budget.
	 */
	if (unlikely(!list_empty(&n->poll_list))) {
		pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
			     n->dev ? n->dev->name : "backlog");
		goto out_unlock;
	}

5534 5535 5536 5537 5538 5539 5540 5541
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

5542
static __latent_entropy void net_rx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
5543
{
5544
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
5545 5546
	unsigned long time_limit = jiffies +
		usecs_to_jiffies(netdev_budget_usecs);
5547
	int budget = netdev_budget;
E
Eric Dumazet 已提交
5548 5549
	LIST_HEAD(list);
	LIST_HEAD(repoll);
5550

L
Linus Torvalds 已提交
5551
	local_irq_disable();
E
Eric Dumazet 已提交
5552 5553
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
5554

H
Herbert Xu 已提交
5555
	for (;;) {
5556
		struct napi_struct *n;
L
Linus Torvalds 已提交
5557

H
Herbert Xu 已提交
5558 5559
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
5560
				goto out;
H
Herbert Xu 已提交
5561 5562 5563
			break;
		}

5564 5565 5566
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
5567
		/* If softirq window is exhausted then punt.
5568 5569
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
5570
		 */
H
Herbert Xu 已提交
5571 5572 5573 5574 5575
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
5576
	}
E
Eric Dumazet 已提交
5577 5578 5579 5580 5581 5582 5583 5584 5585

	local_irq_disable();

	list_splice_tail_init(&sd->poll_list, &list);
	list_splice_tail(&repoll, &list);
	list_splice(&list, &sd->poll_list);
	if (!list_empty(&sd->poll_list))
		__raise_softirq_irqoff(NET_RX_SOFTIRQ);

5586
	net_rps_action_and_irq_enable(sd);
5587 5588
out:
	__kfree_skb_flush();
L
Linus Torvalds 已提交
5589 5590
}

5591
struct netdev_adjacent {
J
Jiri Pirko 已提交
5592
	struct net_device *dev;
5593 5594

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
5595
	bool master;
5596 5597 5598 5599

	/* counter for the number of times this device was added to us */
	u16 ref_nr;

5600 5601 5602
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
5603 5604 5605 5606
	struct list_head list;
	struct rcu_head rcu;
};

5607
static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
5608
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
5609
{
5610 5611
	struct netdev_adjacent *adj;

5612
	list_for_each_entry(adj, adj_list, list) {
5613 5614
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
5615 5616 5617 5618
	}
	return NULL;
}

5619 5620 5621 5622 5623 5624 5625
static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
{
	struct net_device *dev = data;

	return upper_dev == dev;
}

J
Jiri Pirko 已提交
5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639
/**
 * netdev_has_upper_dev - Check if device is linked to an upper device
 * @dev: device
 * @upper_dev: upper device to check
 *
 * Find out if a device is linked to specified upper device and return true
 * in case it is. Note that this checks only immediate upper device,
 * not through a complete stack of devices. The caller must hold the RTNL lock.
 */
bool netdev_has_upper_dev(struct net_device *dev,
			  struct net_device *upper_dev)
{
	ASSERT_RTNL();

5640 5641
	return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
					     upper_dev);
J
Jiri Pirko 已提交
5642 5643 5644
}
EXPORT_SYMBOL(netdev_has_upper_dev);

5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662
/**
 * netdev_has_upper_dev_all - Check if device is linked to an upper device
 * @dev: device
 * @upper_dev: upper device to check
 *
 * Find out if a device is linked to specified upper device and return true
 * in case it is. Note that this checks the entire upper device chain.
 * The caller must hold rcu lock.
 */

bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
				  struct net_device *upper_dev)
{
	return !!netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
					       upper_dev);
}
EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);

J
Jiri Pirko 已提交
5663 5664 5665 5666 5667 5668 5669
/**
 * netdev_has_any_upper_dev - Check if device is linked to some device
 * @dev: device
 *
 * Find out if a device is linked to an upper device and return true in case
 * it is. The caller must hold the RTNL lock.
 */
S
stephen hemminger 已提交
5670
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
5671 5672 5673
{
	ASSERT_RTNL();

5674
	return !list_empty(&dev->adj_list.upper);
J
Jiri Pirko 已提交
5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685
}

/**
 * netdev_master_upper_dev_get - Get master upper device
 * @dev: device
 *
 * Find a master upper device and return pointer to it or NULL in case
 * it's not there. The caller must hold the RTNL lock.
 */
struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
{
5686
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5687 5688 5689

	ASSERT_RTNL();

5690
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
5691 5692
		return NULL;

5693
	upper = list_first_entry(&dev->adj_list.upper,
5694
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5695 5696 5697 5698 5699 5700
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

5701 5702 5703 5704 5705 5706 5707 5708 5709 5710 5711 5712 5713 5714
/**
 * netdev_has_any_lower_dev - Check if device is linked to some device
 * @dev: device
 *
 * Find out if a device is linked to a lower device and return true in case
 * it is. The caller must hold the RTNL lock.
 */
static bool netdev_has_any_lower_dev(struct net_device *dev)
{
	ASSERT_RTNL();

	return !list_empty(&dev->adj_list.lower);
}

5715 5716 5717 5718 5719 5720 5721 5722 5723 5724
void *netdev_adjacent_get_private(struct list_head *adj_list)
{
	struct netdev_adjacent *adj;

	adj = list_entry(adj_list, struct netdev_adjacent, list);

	return adj->private;
}
EXPORT_SYMBOL(netdev_adjacent_get_private);

5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750
/**
 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next device from the dev's upper list, starting from iter
 * position. The caller must hold RCU read lock.
 */
struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
						 struct list_head **iter)
{
	struct netdev_adjacent *upper;

	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());

	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

	if (&upper->list == &dev->adj_list.upper)
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}
EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);

5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794 5795
static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
						    struct list_head **iter)
{
	struct netdev_adjacent *upper;

	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());

	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

	if (&upper->list == &dev->adj_list.upper)
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}

int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
				  int (*fn)(struct net_device *dev,
					    void *data),
				  void *data)
{
	struct net_device *udev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.upper,
	     udev = netdev_next_upper_dev_rcu(dev, &iter);
	     udev;
	     udev = netdev_next_upper_dev_rcu(dev, &iter)) {
		/* first is the upper device itself */
		ret = fn(udev, data);
		if (ret)
			return ret;

		/* then look at all of its upper devices */
		ret = netdev_walk_all_upper_dev_rcu(udev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);

5796 5797 5798 5799 5800 5801 5802 5803 5804
/**
 * netdev_lower_get_next_private - Get the next ->private from the
 *				   lower neighbour list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 * list, starting from iter position. The caller must hold either hold the
 * RTNL lock or its own locking that guarantees that the neighbour lower
5805
 * list will remain unchanged.
5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816
 */
void *netdev_lower_get_next_private(struct net_device *dev,
				    struct list_head **iter)
{
	struct netdev_adjacent *lower;

	lower = list_entry(*iter, struct netdev_adjacent, list);

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

5817
	*iter = lower->list.next;
5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_get_next_private);

/**
 * netdev_lower_get_next_private_rcu - Get the next ->private from the
 *				       lower neighbour list, RCU
 *				       variant
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 * list, starting from iter position. The caller must hold RCU read lock.
 */
void *netdev_lower_get_next_private_rcu(struct net_device *dev,
					struct list_head **iter)
{
	struct netdev_adjacent *lower;

	WARN_ON_ONCE(!rcu_read_lock_held());

	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

5845
	*iter = &lower->list;
5846 5847 5848 5849 5850

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);

5851 5852 5853 5854 5855 5856 5857 5858 5859
/**
 * netdev_lower_get_next - Get the next device from the lower neighbour
 *                         list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent from the dev's lower neighbour
 * list, starting from iter position. The caller must hold RTNL lock or
 * its own locking that guarantees that the neighbour lower
5860
 * list will remain unchanged.
5861 5862 5863 5864 5865
 */
void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
{
	struct netdev_adjacent *lower;

5866
	lower = list_entry(*iter, struct netdev_adjacent, list);
5867 5868 5869 5870

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

5871
	*iter = lower->list.next;
5872 5873 5874 5875 5876

	return lower->dev;
}
EXPORT_SYMBOL(netdev_lower_get_next);

5877 5878 5879 5880 5881
static struct net_device *netdev_next_lower_dev(struct net_device *dev,
						struct list_head **iter)
{
	struct netdev_adjacent *lower;

5882
	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
5883 5884 5885 5886

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

5887
	*iter = &lower->list;
5888 5889 5890 5891 5892 5893 5894 5895 5896 5897 5898 5899 5900 5901 5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912 5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935 5936 5937 5938 5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961

	return lower->dev;
}

int netdev_walk_all_lower_dev(struct net_device *dev,
			      int (*fn)(struct net_device *dev,
					void *data),
			      void *data)
{
	struct net_device *ldev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.lower,
	     ldev = netdev_next_lower_dev(dev, &iter);
	     ldev;
	     ldev = netdev_next_lower_dev(dev, &iter)) {
		/* first is the lower device itself */
		ret = fn(ldev, data);
		if (ret)
			return ret;

		/* then look at all of its lower devices */
		ret = netdev_walk_all_lower_dev(ldev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);

static struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
						    struct list_head **iter)
{
	struct netdev_adjacent *lower;

	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
	if (&lower->list == &dev->adj_list.lower)
		return NULL;

	*iter = &lower->list;

	return lower->dev;
}

int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
				  int (*fn)(struct net_device *dev,
					    void *data),
				  void *data)
{
	struct net_device *ldev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.lower,
	     ldev = netdev_next_lower_dev_rcu(dev, &iter);
	     ldev;
	     ldev = netdev_next_lower_dev_rcu(dev, &iter)) {
		/* first is the lower device itself */
		ret = fn(ldev, data);
		if (ret)
			return ret;

		/* then look at all of its lower devices */
		ret = netdev_walk_all_lower_dev_rcu(ldev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);

5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982
/**
 * netdev_lower_get_first_private_rcu - Get the first ->private from the
 *				       lower neighbour list, RCU
 *				       variant
 * @dev: device
 *
 * Gets the first netdev_adjacent->private from the dev's lower neighbour
 * list. The caller must hold RCU read lock.
 */
void *netdev_lower_get_first_private_rcu(struct net_device *dev)
{
	struct netdev_adjacent *lower;

	lower = list_first_or_null_rcu(&dev->adj_list.lower,
			struct netdev_adjacent, list);
	if (lower)
		return lower->private;
	return NULL;
}
EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);

J
Jiri Pirko 已提交
5983 5984 5985 5986 5987 5988 5989 5990 5991
/**
 * netdev_master_upper_dev_get_rcu - Get master upper device
 * @dev: device
 *
 * Find a master upper device and return pointer to it or NULL in case
 * it's not there. The caller must hold the RCU read lock.
 */
struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
{
5992
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5993

5994
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
5995
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5996 5997 5998 5999 6000 6001
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

6002
static int netdev_adjacent_sysfs_add(struct net_device *dev,
6003 6004 6005 6006
			      struct net_device *adj_dev,
			      struct list_head *dev_list)
{
	char linkname[IFNAMSIZ+7];
6007

6008 6009 6010 6011 6012
	sprintf(linkname, dev_list == &dev->adj_list.upper ?
		"upper_%s" : "lower_%s", adj_dev->name);
	return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
				 linkname);
}
6013
static void netdev_adjacent_sysfs_del(struct net_device *dev,
6014 6015 6016 6017
			       char *name,
			       struct list_head *dev_list)
{
	char linkname[IFNAMSIZ+7];
6018

6019 6020 6021 6022 6023
	sprintf(linkname, dev_list == &dev->adj_list.upper ?
		"upper_%s" : "lower_%s", name);
	sysfs_remove_link(&(dev->dev.kobj), linkname);
}

6024 6025 6026 6027 6028 6029 6030 6031
static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
						 struct net_device *adj_dev,
						 struct list_head *dev_list)
{
	return (dev_list == &dev->adj_list.upper ||
		dev_list == &dev->adj_list.lower) &&
		net_eq(dev_net(dev), dev_net(adj_dev));
}
6032

6033 6034
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
6035
					struct list_head *dev_list,
6036
					void *private, bool master)
6037 6038
{
	struct netdev_adjacent *adj;
6039
	int ret;
6040

6041
	adj = __netdev_find_adj(adj_dev, dev_list);
6042 6043

	if (adj) {
6044
		adj->ref_nr += 1;
6045 6046 6047
		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
			 dev->name, adj_dev->name, adj->ref_nr);

6048 6049 6050 6051 6052 6053 6054 6055 6056
		return 0;
	}

	adj = kmalloc(sizeof(*adj), GFP_KERNEL);
	if (!adj)
		return -ENOMEM;

	adj->dev = adj_dev;
	adj->master = master;
6057
	adj->ref_nr = 1;
6058
	adj->private = private;
6059
	dev_hold(adj_dev);
6060

6061 6062
	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
6063

6064
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
6065
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
6066 6067 6068 6069
		if (ret)
			goto free_adj;
	}

6070
	/* Ensure that master link is always the first item in list. */
6071 6072 6073 6074
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
6075
			goto remove_symlinks;
6076

6077
		list_add_rcu(&adj->list, dev_list);
6078
	} else {
6079
		list_add_tail_rcu(&adj->list, dev_list);
6080
	}
6081 6082

	return 0;
6083

6084
remove_symlinks:
6085
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
6086
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
6087 6088
free_adj:
	kfree(adj);
6089
	dev_put(adj_dev);
6090 6091

	return ret;
6092 6093
}

S
stephen hemminger 已提交
6094 6095
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
6096
					 u16 ref_nr,
S
stephen hemminger 已提交
6097
					 struct list_head *dev_list)
6098 6099 6100
{
	struct netdev_adjacent *adj;

6101 6102 6103
	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
		 dev->name, adj_dev->name, ref_nr);

6104
	adj = __netdev_find_adj(adj_dev, dev_list);
6105

6106
	if (!adj) {
6107
		pr_err("Adjacency does not exist for device %s from %s\n",
6108
		       dev->name, adj_dev->name);
6109 6110
		WARN_ON(1);
		return;
6111
	}
6112

6113
	if (adj->ref_nr > ref_nr) {
6114 6115 6116
		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
			 dev->name, adj_dev->name, ref_nr,
			 adj->ref_nr - ref_nr);
6117
		adj->ref_nr -= ref_nr;
6118 6119 6120
		return;
	}

6121 6122 6123
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

6124
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
6125
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
6126

6127
	list_del_rcu(&adj->list);
6128
	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
6129
		 adj_dev->name, dev->name, adj_dev->name);
6130 6131 6132 6133
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
6134 6135 6136 6137 6138
static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
					    struct net_device *upper_dev,
					    struct list_head *up_list,
					    struct list_head *down_list,
					    void *private, bool master)
6139 6140 6141
{
	int ret;

6142
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
6143
					   private, master);
6144 6145 6146
	if (ret)
		return ret;

6147
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
6148
					   private, false);
6149
	if (ret) {
6150
		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
6151 6152 6153 6154 6155 6156
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
6157 6158
static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
					       struct net_device *upper_dev,
6159
					       u16 ref_nr,
S
stephen hemminger 已提交
6160 6161
					       struct list_head *up_list,
					       struct list_head *down_list)
6162
{
6163 6164
	__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
6165 6166
}

S
stephen hemminger 已提交
6167 6168 6169
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
6170
{
6171 6172 6173 6174
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->adj_list.upper,
						&upper_dev->adj_list.lower,
						private, master);
6175 6176
}

S
stephen hemminger 已提交
6177 6178
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
6179
{
6180
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
6181 6182 6183
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
6184

J
Jiri Pirko 已提交
6185
static int __netdev_upper_dev_link(struct net_device *dev,
6186
				   struct net_device *upper_dev, bool master,
6187
				   void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
6188
{
6189
	struct netdev_notifier_changeupper_info changeupper_info;
6190
	int ret = 0;
J
Jiri Pirko 已提交
6191 6192 6193 6194 6195 6196 6197

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
6198
	if (netdev_has_upper_dev(upper_dev, dev))
J
Jiri Pirko 已提交
6199 6200
		return -EBUSY;

6201
	if (netdev_has_upper_dev(dev, upper_dev))
J
Jiri Pirko 已提交
6202 6203 6204 6205 6206
		return -EEXIST;

	if (master && netdev_master_upper_dev_get(dev))
		return -EBUSY;

6207 6208 6209
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = master;
	changeupper_info.linking = true;
6210
	changeupper_info.upper_info = upper_info;
6211

6212 6213 6214 6215 6216 6217
	ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

6218
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
6219
						   master);
6220 6221
	if (ret)
		return ret;
J
Jiri Pirko 已提交
6222

6223 6224 6225 6226
	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
6227
		goto rollback;
6228

J
Jiri Pirko 已提交
6229
	return 0;
6230

6231
rollback:
6232
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
6233 6234

	return ret;
J
Jiri Pirko 已提交
6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249
}

/**
 * netdev_upper_dev_link - Add a link to the upper device
 * @dev: device
 * @upper_dev: new upper device
 *
 * Adds a link to device which is upper to this one. The caller must hold
 * the RTNL lock. On a failure a negative errno code is returned.
 * On success the reference counts are adjusted and the function
 * returns zero.
 */
int netdev_upper_dev_link(struct net_device *dev,
			  struct net_device *upper_dev)
{
6250
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL, NULL);
J
Jiri Pirko 已提交
6251 6252 6253 6254 6255 6256 6257
}
EXPORT_SYMBOL(netdev_upper_dev_link);

/**
 * netdev_master_upper_dev_link - Add a master link to the upper device
 * @dev: device
 * @upper_dev: new upper device
6258
 * @upper_priv: upper device private
6259
 * @upper_info: upper info to be passed down via notifier
J
Jiri Pirko 已提交
6260 6261 6262 6263 6264 6265 6266 6267
 *
 * Adds a link to device which is upper to this one. In this case, only
 * one master upper device can be linked, although other non-master devices
 * might be linked as well. The caller must hold the RTNL lock.
 * On a failure a negative errno code is returned. On success the reference
 * counts are adjusted and the function returns zero.
 */
int netdev_master_upper_dev_link(struct net_device *dev,
6268
				 struct net_device *upper_dev,
6269
				 void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
6270
{
6271 6272
	return __netdev_upper_dev_link(dev, upper_dev, true,
				       upper_priv, upper_info);
J
Jiri Pirko 已提交
6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 6286
}
EXPORT_SYMBOL(netdev_master_upper_dev_link);

/**
 * netdev_upper_dev_unlink - Removes a link to upper device
 * @dev: device
 * @upper_dev: new upper device
 *
 * Removes a link to device which is upper to this one. The caller must hold
 * the RTNL lock.
 */
void netdev_upper_dev_unlink(struct net_device *dev,
			     struct net_device *upper_dev)
{
6287
	struct netdev_notifier_changeupper_info changeupper_info;
6288

J
Jiri Pirko 已提交
6289 6290
	ASSERT_RTNL();

6291 6292 6293 6294
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
	changeupper_info.linking = false;

6295 6296 6297
	call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
				      &changeupper_info.info);

6298
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
6299

6300 6301
	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
				      &changeupper_info.info);
J
Jiri Pirko 已提交
6302 6303 6304
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

6305 6306 6307
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
6308
 * @bonding_info: info to dispatch
6309 6310 6311 6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324
 *
 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
 * The caller must hold the RTNL lock.
 */
void netdev_bonding_info_change(struct net_device *dev,
				struct netdev_bonding_info *bonding_info)
{
	struct netdev_notifier_bonding_info	info;

	memcpy(&info.bonding_info, bonding_info,
	       sizeof(struct netdev_bonding_info));
	call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev,
				      &info.info);
}
EXPORT_SYMBOL(netdev_bonding_info_change);

E
Eric Dumazet 已提交
6325
static void netdev_adjacent_add_links(struct net_device *dev)
6326 6327 6328 6329 6330 6331
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
6332
		if (!net_eq(net, dev_net(iter->dev)))
6333 6334 6335 6336 6337 6338 6339 6340
			continue;
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(dev, iter->dev,
					  &dev->adj_list.upper);
	}

	list_for_each_entry(iter, &dev->adj_list.lower, list) {
W
Wei Tang 已提交
6341
		if (!net_eq(net, dev_net(iter->dev)))
6342 6343 6344 6345 6346 6347 6348 6349
			continue;
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(dev, iter->dev,
					  &dev->adj_list.lower);
	}
}

E
Eric Dumazet 已提交
6350
static void netdev_adjacent_del_links(struct net_device *dev)
6351 6352 6353 6354 6355 6356
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
6357
		if (!net_eq(net, dev_net(iter->dev)))
6358 6359 6360 6361 6362 6363 6364 6365
			continue;
		netdev_adjacent_sysfs_del(iter->dev, dev->name,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_del(dev, iter->dev->name,
					  &dev->adj_list.upper);
	}

	list_for_each_entry(iter, &dev->adj_list.lower, list) {
W
Wei Tang 已提交
6366
		if (!net_eq(net, dev_net(iter->dev)))
6367 6368 6369 6370 6371 6372 6373 6374
			continue;
		netdev_adjacent_sysfs_del(iter->dev, dev->name,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_del(dev, iter->dev->name,
					  &dev->adj_list.lower);
	}
}

6375
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
6376
{
6377
	struct netdev_adjacent *iter;
6378

6379 6380
	struct net *net = dev_net(dev);

6381
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
6382
		if (!net_eq(net, dev_net(iter->dev)))
6383
			continue;
6384 6385 6386 6387 6388
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
6389

6390
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
W
Wei Tang 已提交
6391
		if (!net_eq(net, dev_net(iter->dev)))
6392
			continue;
6393 6394 6395 6396 6397
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
6398 6399 6400 6401 6402 6403 6404 6405 6406
}

void *netdev_lower_dev_get_private(struct net_device *dev,
				   struct net_device *lower_dev)
{
	struct netdev_adjacent *lower;

	if (!lower_dev)
		return NULL;
6407
	lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
6408 6409 6410 6411 6412 6413 6414
	if (!lower)
		return NULL;

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_dev_get_private);

6415

6416
int dev_get_nest_level(struct net_device *dev)
6417 6418 6419 6420 6421 6422 6423 6424 6425
{
	struct net_device *lower = NULL;
	struct list_head *iter;
	int max_nest = -1;
	int nest;

	ASSERT_RTNL();

	netdev_for_each_lower_dev(dev, lower, iter) {
6426
		nest = dev_get_nest_level(lower);
6427 6428 6429 6430
		if (max_nest < nest)
			max_nest = nest;
	}

6431
	return max_nest + 1;
6432 6433 6434
}
EXPORT_SYMBOL(dev_get_nest_level);

6435 6436 6437 6438 6439 6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454
/**
 * netdev_lower_change - Dispatch event about lower device state change
 * @lower_dev: device
 * @lower_state_info: state to dispatch
 *
 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
 * The caller must hold the RTNL lock.
 */
void netdev_lower_state_changed(struct net_device *lower_dev,
				void *lower_state_info)
{
	struct netdev_notifier_changelowerstate_info changelowerstate_info;

	ASSERT_RTNL();
	changelowerstate_info.lower_state_info = lower_state_info;
	call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, lower_dev,
				      &changelowerstate_info.info);
}
EXPORT_SYMBOL(netdev_lower_state_changed);

6455 6456
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
6457 6458
	const struct net_device_ops *ops = dev->netdev_ops;

6459
	if (ops->ndo_change_rx_flags)
6460
		ops->ndo_change_rx_flags(dev, flags);
6461 6462
}

6463
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6464
{
6465
	unsigned int old_flags = dev->flags;
6466 6467
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
6468

6469 6470
	ASSERT_RTNL();

6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481
	dev->flags |= IFF_PROMISC;
	dev->promiscuity += inc;
	if (dev->promiscuity == 0) {
		/*
		 * Avoid overflow.
		 * If inc causes overflow, untouch promisc and return error.
		 */
		if (inc < 0)
			dev->flags &= ~IFF_PROMISC;
		else {
			dev->promiscuity -= inc;
6482 6483
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
6484 6485 6486
			return -EOVERFLOW;
		}
	}
6487
	if (dev->flags != old_flags) {
6488 6489 6490
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
6491 6492
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
6493 6494 6495 6496 6497
			audit_log(current->audit_context, GFP_ATOMIC,
				AUDIT_ANOM_PROMISCUOUS,
				"dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
				dev->name, (dev->flags & IFF_PROMISC),
				(old_flags & IFF_PROMISC),
6498
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
6499 6500
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
6501
				audit_get_sessionid(current));
6502
		}
6503

6504
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
6505
	}
6506 6507
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
6508
	return 0;
L
Linus Torvalds 已提交
6509 6510
}

6511 6512 6513 6514 6515 6516 6517 6518 6519
/**
 *	dev_set_promiscuity	- update promiscuity count on a device
 *	@dev: device
 *	@inc: modifier
 *
 *	Add or remove promiscuity from a device. While the count in the device
 *	remains above zero the interface remains promiscuous. Once it hits zero
 *	the device reverts back to normal filtering operation. A negative inc
 *	value is used to drop promiscuity on the device.
6520
 *	Return 0 if successful or a negative errno code on error.
6521
 */
6522
int dev_set_promiscuity(struct net_device *dev, int inc)
6523
{
6524
	unsigned int old_flags = dev->flags;
6525
	int err;
6526

6527
	err = __dev_set_promiscuity(dev, inc, true);
6528
	if (err < 0)
6529
		return err;
6530 6531
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
6532
	return err;
6533
}
E
Eric Dumazet 已提交
6534
EXPORT_SYMBOL(dev_set_promiscuity);
6535

6536
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6537
{
6538
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
6539

6540 6541
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6542
	dev->flags |= IFF_ALLMULTI;
6543 6544 6545 6546 6547 6548 6549 6550 6551 6552
	dev->allmulti += inc;
	if (dev->allmulti == 0) {
		/*
		 * Avoid overflow.
		 * If inc causes overflow, untouch allmulti and return error.
		 */
		if (inc < 0)
			dev->flags &= ~IFF_ALLMULTI;
		else {
			dev->allmulti -= inc;
6553 6554
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
6555 6556 6557
			return -EOVERFLOW;
		}
	}
6558
	if (dev->flags ^ old_flags) {
6559
		dev_change_rx_flags(dev, IFF_ALLMULTI);
6560
		dev_set_rx_mode(dev);
6561 6562 6563
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
6564
	}
6565
	return 0;
6566
}
6567 6568 6569 6570 6571 6572 6573 6574 6575 6576 6577 6578 6579 6580 6581 6582 6583 6584

/**
 *	dev_set_allmulti	- update allmulti count on a device
 *	@dev: device
 *	@inc: modifier
 *
 *	Add or remove reception of all multicast frames to a device. While the
 *	count in the device remains above zero the interface remains listening
 *	to all interfaces. Once it hits zero the device reverts back to normal
 *	filtering operation. A negative @inc value is used to drop the counter
 *	when releasing a resource needing all multicasts.
 *	Return 0 if successful or a negative errno code on error.
 */

int dev_set_allmulti(struct net_device *dev, int inc)
{
	return __dev_set_allmulti(dev, inc, true);
}
E
Eric Dumazet 已提交
6585
EXPORT_SYMBOL(dev_set_allmulti);
6586 6587 6588 6589

/*
 *	Upload unicast and multicast address lists to device and
 *	configure RX filtering. When the device doesn't support unicast
J
Joe Perches 已提交
6590
 *	filtering it is put in promiscuous mode while unicast addresses
6591 6592 6593 6594
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
6595 6596
	const struct net_device_ops *ops = dev->netdev_ops;

6597 6598 6599 6600 6601
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
6602
		return;
6603

6604
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
6605 6606 6607
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
6608
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
6609
			__dev_set_promiscuity(dev, 1, false);
6610
			dev->uc_promisc = true;
6611
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
6612
			__dev_set_promiscuity(dev, -1, false);
6613
			dev->uc_promisc = false;
6614 6615
		}
	}
6616 6617 6618

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
6619 6620 6621 6622
}

void dev_set_rx_mode(struct net_device *dev)
{
6623
	netif_addr_lock_bh(dev);
6624
	__dev_set_rx_mode(dev);
6625
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
6626 6627
}

6628 6629 6630 6631 6632 6633
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
6634
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
6635
{
6636
	unsigned int flags;
L
Linus Torvalds 已提交
6637 6638 6639

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
6640 6641 6642
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
6643 6644 6645
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
6646 6647 6648 6649 6650 6651 6652 6653
	if (netif_running(dev)) {
		if (netif_oper_up(dev))
			flags |= IFF_RUNNING;
		if (netif_carrier_ok(dev))
			flags |= IFF_LOWER_UP;
		if (netif_dormant(dev))
			flags |= IFF_DORMANT;
	}
L
Linus Torvalds 已提交
6654 6655 6656

	return flags;
}
E
Eric Dumazet 已提交
6657
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
6658

6659
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
6660
{
6661
	unsigned int old_flags = dev->flags;
6662
	int ret;
L
Linus Torvalds 已提交
6663

6664 6665
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6666 6667 6668 6669 6670 6671 6672 6673 6674 6675 6676 6677 6678 6679
	/*
	 *	Set the flags on our device.
	 */

	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
			       IFF_AUTOMEDIA)) |
		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
				    IFF_ALLMULTI));

	/*
	 *	Load in the correct multicast list now the flags have changed.
	 */

6680 6681
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
6682

6683
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6684 6685 6686 6687 6688 6689 6690 6691

	/*
	 *	Have we downed the interface. We handle IFF_UP ourselves
	 *	according to user attempts to set it, rather than blindly
	 *	setting it.
	 */

	ret = 0;
6692
	if ((old_flags ^ flags) & IFF_UP)
6693
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
6694 6695

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
6696
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
6697
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
6698

L
Linus Torvalds 已提交
6699
		dev->gflags ^= IFF_PROMISC;
6700 6701 6702 6703

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6704 6705 6706
	}

	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
6707 6708
	 * is important. Some (broken) drivers set IFF_PROMISC, when
	 * IFF_ALLMULTI is requested not asking us and not reporting.
L
Linus Torvalds 已提交
6709 6710
	 */
	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
E
Eric Dumazet 已提交
6711 6712
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
6713
		dev->gflags ^= IFF_ALLMULTI;
6714
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
6715 6716
	}

6717 6718 6719
	return ret;
}

6720 6721
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
6722 6723 6724
{
	unsigned int changes = dev->flags ^ old_flags;

6725
	if (gchanges)
6726
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
6727

6728 6729 6730 6731 6732 6733 6734 6735
	if (changes & IFF_UP) {
		if (dev->flags & IFF_UP)
			call_netdevice_notifiers(NETDEV_UP, dev);
		else
			call_netdevice_notifiers(NETDEV_DOWN, dev);
	}

	if (dev->flags & IFF_UP &&
6736 6737 6738 6739 6740 6741 6742
	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = changes;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
	}
6743 6744 6745 6746 6747 6748 6749 6750 6751 6752
}

/**
 *	dev_change_flags - change device settings
 *	@dev: device
 *	@flags: device state flags
 *
 *	Change settings on device based state flags. The flags are
 *	in the userspace exported format.
 */
6753
int dev_change_flags(struct net_device *dev, unsigned int flags)
6754
{
6755
	int ret;
6756
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
6757 6758 6759 6760 6761

	ret = __dev_change_flags(dev, flags);
	if (ret < 0)
		return ret;

6762
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
6763
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
6764 6765
	return ret;
}
E
Eric Dumazet 已提交
6766
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
6767

6768 6769 6770 6771 6772 6773 6774 6775 6776 6777 6778
static int __dev_set_mtu(struct net_device *dev, int new_mtu)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (ops->ndo_change_mtu)
		return ops->ndo_change_mtu(dev, new_mtu);

	dev->mtu = new_mtu;
	return 0;
}

6779 6780 6781 6782 6783 6784 6785
/**
 *	dev_set_mtu - Change maximum transfer unit
 *	@dev: device
 *	@new_mtu: new transfer unit
 *
 *	Change the maximum transfer size of the network device.
 */
L
Linus Torvalds 已提交
6786 6787
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
6788
	int err, orig_mtu;
L
Linus Torvalds 已提交
6789 6790 6791 6792

	if (new_mtu == dev->mtu)
		return 0;

6793 6794 6795 6796
	/* MTU must be positive, and in range */
	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
		net_err_ratelimited("%s: Invalid MTU %d requested, hw min %d\n",
				    dev->name, new_mtu, dev->min_mtu);
L
Linus Torvalds 已提交
6797
		return -EINVAL;
6798 6799 6800 6801
	}

	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
		net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
6802
				    dev->name, new_mtu, dev->max_mtu);
6803 6804
		return -EINVAL;
	}
L
Linus Torvalds 已提交
6805 6806 6807 6808

	if (!netif_device_present(dev))
		return -ENODEV;

6809 6810 6811 6812
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
6813

6814 6815
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
6816

6817 6818 6819 6820 6821 6822 6823 6824 6825 6826 6827
	if (!err) {
		err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
		err = notifier_to_errno(err);
		if (err) {
			/* setting mtu back and notifying everyone again,
			 * so that they have a chance to revert changes.
			 */
			__dev_set_mtu(dev, orig_mtu);
			call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
		}
	}
L
Linus Torvalds 已提交
6828 6829
	return err;
}
E
Eric Dumazet 已提交
6830
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
6831

6832 6833 6834 6835 6836 6837 6838 6839 6840 6841 6842
/**
 *	dev_set_group - Change group this device belongs to
 *	@dev: device
 *	@new_group: group this device should belong to
 */
void dev_set_group(struct net_device *dev, int new_group)
{
	dev->group = new_group;
}
EXPORT_SYMBOL(dev_set_group);

6843 6844 6845 6846 6847 6848 6849
/**
 *	dev_set_mac_address - Change Media Access Control Address
 *	@dev: device
 *	@sa: new address
 *
 *	Change the hardware (MAC) address of the device
 */
L
Linus Torvalds 已提交
6850 6851
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
6852
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
6853 6854
	int err;

6855
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
6856 6857 6858 6859 6860
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
6861
	err = ops->ndo_set_mac_address(dev, sa);
6862 6863
	if (err)
		return err;
J
Jiri Pirko 已提交
6864
	dev->addr_assign_type = NET_ADDR_SET;
6865
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
6866
	add_device_randomness(dev->dev_addr, dev->addr_len);
6867
	return 0;
L
Linus Torvalds 已提交
6868
}
E
Eric Dumazet 已提交
6869
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
6870

J
Jiri Pirko 已提交
6871 6872 6873
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
6874
 *	@new_carrier: new value
J
Jiri Pirko 已提交
6875 6876 6877 6878 6879 6880 6881 6882 6883 6884 6885 6886 6887 6888 6889
 *
 *	Change device carrier
 */
int dev_change_carrier(struct net_device *dev, bool new_carrier)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_change_carrier)
		return -EOPNOTSUPP;
	if (!netif_device_present(dev))
		return -ENODEV;
	return ops->ndo_change_carrier(dev, new_carrier);
}
EXPORT_SYMBOL(dev_change_carrier);

6890 6891 6892 6893 6894 6895 6896 6897
/**
 *	dev_get_phys_port_id - Get device physical port ID
 *	@dev: device
 *	@ppid: port ID
 *
 *	Get device physical port ID
 */
int dev_get_phys_port_id(struct net_device *dev,
6898
			 struct netdev_phys_item_id *ppid)
6899 6900 6901 6902 6903 6904 6905 6906 6907
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_get_phys_port_id)
		return -EOPNOTSUPP;
	return ops->ndo_get_phys_port_id(dev, ppid);
}
EXPORT_SYMBOL(dev_get_phys_port_id);

6908 6909 6910 6911
/**
 *	dev_get_phys_port_name - Get device physical port name
 *	@dev: device
 *	@name: port name
6912
 *	@len: limit of bytes to copy to name
6913 6914 6915 6916 6917 6918 6919 6920 6921 6922 6923 6924 6925 6926
 *
 *	Get device physical port name
 */
int dev_get_phys_port_name(struct net_device *dev,
			   char *name, size_t len)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_get_phys_port_name)
		return -EOPNOTSUPP;
	return ops->ndo_get_phys_port_name(dev, name, len);
}
EXPORT_SYMBOL(dev_get_phys_port_name);

6927 6928 6929 6930 6931 6932 6933 6934 6935 6936 6937 6938 6939 6940 6941 6942 6943 6944 6945 6946
/**
 *	dev_change_proto_down - update protocol port state information
 *	@dev: device
 *	@proto_down: new value
 *
 *	This info can be used by switch drivers to set the phys state of the
 *	port.
 */
int dev_change_proto_down(struct net_device *dev, bool proto_down)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_change_proto_down)
		return -EOPNOTSUPP;
	if (!netif_device_present(dev))
		return -ENODEV;
	return ops->ndo_change_proto_down(dev, proto_down);
}
EXPORT_SYMBOL(dev_change_proto_down);

6947
u8 __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, u32 *prog_id)
6948 6949 6950 6951 6952 6953 6954 6955
{
	struct netdev_xdp xdp;

	memset(&xdp, 0, sizeof(xdp));
	xdp.command = XDP_QUERY_PROG;

	/* Query must always succeed. */
	WARN_ON(xdp_op(dev, &xdp) < 0);
M
Martin KaFai Lau 已提交
6956 6957 6958
	if (prog_id)
		*prog_id = xdp.prog_id;

6959 6960 6961 6962
	return xdp.prog_attached;
}

static int dev_xdp_install(struct net_device *dev, xdp_op_t xdp_op,
6963
			   struct netlink_ext_ack *extack, u32 flags,
6964 6965 6966 6967 6968
			   struct bpf_prog *prog)
{
	struct netdev_xdp xdp;

	memset(&xdp, 0, sizeof(xdp));
6969 6970 6971 6972
	if (flags & XDP_FLAGS_HW_MODE)
		xdp.command = XDP_SETUP_PROG_HW;
	else
		xdp.command = XDP_SETUP_PROG;
6973
	xdp.extack = extack;
6974
	xdp.flags = flags;
6975 6976 6977 6978 6979
	xdp.prog = prog;

	return xdp_op(dev, &xdp);
}

6980 6981 6982
/**
 *	dev_change_xdp_fd - set or clear a bpf program for a device rx path
 *	@dev: device
6983
 *	@extack: netlink extended ack
6984
 *	@fd: new program fd or negative value to clear
6985
 *	@flags: xdp-related flags
6986 6987 6988
 *
 *	Set or clear a bpf program for a device
 */
6989 6990
int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
		      int fd, u32 flags)
6991 6992 6993
{
	const struct net_device_ops *ops = dev->netdev_ops;
	struct bpf_prog *prog = NULL;
6994
	xdp_op_t xdp_op, xdp_chk;
6995 6996
	int err;

6997 6998
	ASSERT_RTNL();

6999
	xdp_op = xdp_chk = ops->ndo_xdp;
7000
	if (!xdp_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE)))
7001
		return -EOPNOTSUPP;
D
David S. Miller 已提交
7002 7003
	if (!xdp_op || (flags & XDP_FLAGS_SKB_MODE))
		xdp_op = generic_xdp_install;
7004 7005
	if (xdp_op == xdp_chk)
		xdp_chk = generic_xdp_install;
D
David S. Miller 已提交
7006

7007
	if (fd >= 0) {
M
Martin KaFai Lau 已提交
7008
		if (xdp_chk && __dev_xdp_attached(dev, xdp_chk, NULL))
7009 7010
			return -EEXIST;
		if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) &&
M
Martin KaFai Lau 已提交
7011
		    __dev_xdp_attached(dev, xdp_op, NULL))
7012
			return -EBUSY;
7013

7014 7015 7016 7017 7018
		prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP);
		if (IS_ERR(prog))
			return PTR_ERR(prog);
	}

7019
	err = dev_xdp_install(dev, xdp_op, extack, flags, prog);
7020 7021 7022 7023 7024 7025
	if (err < 0 && prog)
		bpf_prog_put(prog);

	return err;
}

L
Linus Torvalds 已提交
7026 7027
/**
 *	dev_new_index	-	allocate an ifindex
7028
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
7029 7030 7031 7032 7033
 *
 *	Returns a suitable unique value for a new device interface
 *	number.  The caller must hold the rtnl semaphore or the
 *	dev_base_lock to be sure it remains unique.
 */
7034
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
7035
{
7036
	int ifindex = net->ifindex;
7037

L
Linus Torvalds 已提交
7038 7039 7040
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
7041
		if (!__dev_get_by_index(net, ifindex))
7042
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
7043 7044 7045 7046
	}
}

/* Delayed registration/unregisteration */
7047
static LIST_HEAD(net_todo_list);
7048
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
7049

7050
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
7051 7052
{
	list_add_tail(&dev->todo_list, &net_todo_list);
7053
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
7054 7055
}

7056
static void rollback_registered_many(struct list_head *head)
7057
{
7058
	struct net_device *dev, *tmp;
7059
	LIST_HEAD(close_head);
7060

7061 7062 7063
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

7064
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
7065
		/* Some devices call without registering
7066 7067
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
7068 7069
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
7070 7071
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
7072

7073
			WARN_ON(1);
7074 7075
			list_del(&dev->unreg_list);
			continue;
7076
		}
7077
		dev->dismantle = true;
7078
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
7079
	}
7080

7081
	/* If device is running, close it first. */
7082 7083
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
7084
	dev_close_many(&close_head, true);
7085

7086
	list_for_each_entry(dev, head, unreg_list) {
7087 7088
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
7089

7090 7091
		dev->reg_state = NETREG_UNREGISTERING;
	}
7092
	flush_all_backlogs();
7093 7094 7095

	synchronize_net();

7096
	list_for_each_entry(dev, head, unreg_list) {
7097 7098
		struct sk_buff *skb = NULL;

7099 7100
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
7101 7102


7103
		/* Notify protocols, that we are about to destroy
7104 7105
		 * this device. They should clean all the things.
		 */
7106
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7107

7108 7109
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7110
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0,
7111 7112
						     GFP_KERNEL);

7113 7114 7115
		/*
		 *	Flush the unicast and multicast chains
		 */
7116
		dev_uc_flush(dev);
7117
		dev_mc_flush(dev);
7118

7119 7120
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
7121

7122 7123
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
7124

J
Jiri Pirko 已提交
7125 7126
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
7127
		WARN_ON(netdev_has_any_lower_dev(dev));
7128

7129 7130
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
7131 7132 7133 7134
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
7135
	}
7136

7137
	synchronize_net();
7138

7139
	list_for_each_entry(dev, head, unreg_list)
7140 7141 7142 7143 7144 7145 7146 7147 7148
		dev_put(dev);
}

static void rollback_registered(struct net_device *dev)
{
	LIST_HEAD(single);

	list_add(&dev->unreg_list, &single);
	rollback_registered_many(&single);
E
Eric Dumazet 已提交
7149
	list_del(&single);
7150 7151
}

7152 7153 7154 7155 7156
static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
	struct net_device *upper, netdev_features_t features)
{
	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
	netdev_features_t feature;
7157
	int feature_bit;
7158

7159 7160
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
7161 7162 7163 7164 7165 7166 7167 7168 7169 7170 7171 7172 7173 7174 7175 7176
		if (!(upper->wanted_features & feature)
		    && (features & feature)) {
			netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
				   &feature, upper->name);
			features &= ~feature;
		}
	}

	return features;
}

static void netdev_sync_lower_features(struct net_device *upper,
	struct net_device *lower, netdev_features_t features)
{
	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
	netdev_features_t feature;
7177
	int feature_bit;
7178

7179 7180
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
7181 7182 7183 7184 7185 7186 7187 7188 7189 7190 7191 7192 7193
		if (!(features & feature) && (lower->features & feature)) {
			netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
				   &feature, lower->name);
			lower->wanted_features &= ~feature;
			netdev_update_features(lower);

			if (unlikely(lower->features & feature))
				netdev_WARN(upper, "failed to disable %pNF on %s!\n",
					    &feature, lower->name);
		}
	}
}

7194 7195
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
7196
{
7197 7198 7199
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
7200
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
7201 7202 7203
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

7204
	/* TSO requires that SG is present as well. */
7205
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
7206
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
7207
		features &= ~NETIF_F_ALL_TSO;
7208 7209
	}

7210 7211 7212 7213 7214 7215 7216 7217 7218 7219 7220 7221 7222
	if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
					!(features & NETIF_F_IP_CSUM)) {
		netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
		features &= ~NETIF_F_TSO;
		features &= ~NETIF_F_TSO_ECN;
	}

	if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
					 !(features & NETIF_F_IPV6_CSUM)) {
		netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
		features &= ~NETIF_F_TSO6;
	}

7223 7224 7225 7226
	/* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
	if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
		features &= ~NETIF_F_TSO_MANGLEID;

7227 7228 7229 7230
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

7231 7232
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
7233
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
7234 7235 7236
		features &= ~NETIF_F_GSO;
	}

7237
	/* UFO needs SG and checksumming */
7238
	if (features & NETIF_F_UFO) {
7239
		/* maybe split UFO into V4 and V6? */
7240 7241 7242
		if (!(features & NETIF_F_HW_CSUM) &&
		    ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) !=
		     (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) {
7243
			netdev_dbg(dev,
7244
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
7245 7246 7247 7248
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
7249
			netdev_dbg(dev,
7250
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
7251 7252 7253 7254
			features &= ~NETIF_F_UFO;
		}
	}

7255 7256 7257 7258 7259 7260 7261 7262
	/* GSO partial features require GSO partial be set */
	if ((features & dev->gso_partial_features) &&
	    !(features & NETIF_F_GSO_PARTIAL)) {
		netdev_dbg(dev,
			   "Dropping partially supported GSO features since no GSO partial.\n");
		features &= ~dev->gso_partial_features;
	}

7263 7264 7265
	return features;
}

7266
int __netdev_update_features(struct net_device *dev)
7267
{
7268
	struct net_device *upper, *lower;
7269
	netdev_features_t features;
7270
	struct list_head *iter;
7271
	int err = -1;
7272

7273 7274
	ASSERT_RTNL();

7275 7276 7277 7278 7279 7280 7281 7282
	features = netdev_get_wanted_features(dev);

	if (dev->netdev_ops->ndo_fix_features)
		features = dev->netdev_ops->ndo_fix_features(dev, features);

	/* driver might be less strict about feature dependencies */
	features = netdev_fix_features(dev, features);

7283 7284 7285 7286
	/* some features can't be enabled if they're off an an upper device */
	netdev_for_each_upper_dev_rcu(dev, upper, iter)
		features = netdev_sync_upper_features(dev, upper, features);

7287
	if (dev->features == features)
7288
		goto sync_lower;
7289

7290 7291
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
7292 7293 7294

	if (dev->netdev_ops->ndo_set_features)
		err = dev->netdev_ops->ndo_set_features(dev, features);
7295 7296
	else
		err = 0;
7297

7298
	if (unlikely(err < 0)) {
7299
		netdev_err(dev,
7300 7301
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
7302 7303 7304 7305
		/* return non-0 since some features might have changed and
		 * it's better to fire a spurious notification than miss it
		 */
		return -1;
7306 7307
	}

7308
sync_lower:
7309 7310 7311 7312 7313 7314
	/* some features must be disabled on lower devices when disabled
	 * on an upper device (think: bonding master or bridge)
	 */
	netdev_for_each_lower_dev(dev, lower, iter)
		netdev_sync_lower_features(dev, lower, features);

7315 7316 7317
	if (!err)
		dev->features = features;

7318
	return err < 0 ? 0 : 1;
7319 7320
}

7321 7322 7323 7324 7325 7326 7327 7328
/**
 *	netdev_update_features - recalculate device features
 *	@dev: the device to check
 *
 *	Recalculate dev->features set and send notifications if it
 *	has changed. Should be called after driver or hardware dependent
 *	conditions might have changed that influence the features.
 */
7329 7330 7331 7332
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
7333 7334 7335
}
EXPORT_SYMBOL(netdev_update_features);

7336 7337 7338 7339 7340 7341 7342 7343 7344 7345 7346 7347 7348 7349 7350 7351 7352
/**
 *	netdev_change_features - recalculate device features
 *	@dev: the device to check
 *
 *	Recalculate dev->features set and send notifications even
 *	if they have not changed. Should be called instead of
 *	netdev_update_features() if also dev->vlan_features might
 *	have changed to allow the changes to be propagated to stacked
 *	VLAN devices.
 */
void netdev_change_features(struct net_device *dev)
{
	__netdev_update_features(dev);
	netdev_features_change(dev);
}
EXPORT_SYMBOL(netdev_change_features);

7353 7354 7355 7356 7357 7358 7359 7360 7361 7362 7363 7364 7365 7366 7367 7368 7369
/**
 *	netif_stacked_transfer_operstate -	transfer operstate
 *	@rootdev: the root or lower level device to transfer state from
 *	@dev: the device to transfer operstate to
 *
 *	Transfer operational state from root to device. This is normally
 *	called when a stacking relationship exists between the root
 *	device and the device(a leaf device).
 */
void netif_stacked_transfer_operstate(const struct net_device *rootdev,
					struct net_device *dev)
{
	if (rootdev->operstate == IF_OPER_DORMANT)
		netif_dormant_on(dev);
	else
		netif_dormant_off(dev);

7370 7371 7372 7373
	if (netif_carrier_ok(rootdev))
		netif_carrier_on(dev);
	else
		netif_carrier_off(dev);
7374 7375 7376
}
EXPORT_SYMBOL(netif_stacked_transfer_operstate);

7377
#ifdef CONFIG_SYSFS
7378 7379 7380
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
7381
	struct netdev_rx_queue *rx;
7382
	size_t sz = count * sizeof(*rx);
7383

T
Tom Herbert 已提交
7384
	BUG_ON(count < 1);
7385

7386 7387 7388 7389
	rx = kvzalloc(sz, GFP_KERNEL | __GFP_REPEAT);
	if (!rx)
		return -ENOMEM;

T
Tom Herbert 已提交
7390 7391 7392
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
7393
		rx[i].dev = dev;
7394 7395
	return 0;
}
T
Tom Herbert 已提交
7396
#endif
7397

C
Changli Gao 已提交
7398 7399 7400 7401 7402 7403 7404
static void netdev_init_one_queue(struct net_device *dev,
				  struct netdev_queue *queue, void *_unused)
{
	/* Initialize queue lock */
	spin_lock_init(&queue->_xmit_lock);
	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
	queue->xmit_lock_owner = -1;
7405
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
7406
	queue->dev = dev;
T
Tom Herbert 已提交
7407 7408 7409
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
7410 7411
}

7412 7413
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
7414
	kvfree(dev->_tx);
7415 7416
}

7417 7418 7419 7420
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
7421
	size_t sz = count * sizeof(*tx);
7422

7423 7424
	if (count < 1 || count > 0xffff)
		return -EINVAL;
7425

7426 7427 7428 7429
	tx = kvzalloc(sz, GFP_KERNEL | __GFP_REPEAT);
	if (!tx)
		return -ENOMEM;

7430
	dev->_tx = tx;
T
Tom Herbert 已提交
7431

7432 7433
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
7434 7435

	return 0;
7436 7437
}

7438 7439 7440 7441 7442 7443
void netif_tx_stop_all_queues(struct net_device *dev)
{
	unsigned int i;

	for (i = 0; i < dev->num_tx_queues; i++) {
		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
7444

7445 7446 7447 7448 7449
		netif_tx_stop_queue(txq);
	}
}
EXPORT_SYMBOL(netif_tx_stop_all_queues);

L
Linus Torvalds 已提交
7450 7451 7452 7453 7454 7455 7456 7457 7458 7459 7460 7461 7462 7463 7464 7465 7466 7467 7468 7469
/**
 *	register_netdevice	- register a network device
 *	@dev: device to register
 *
 *	Take a completed network device structure and add it to the kernel
 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
 *	chain. 0 is returned on success. A negative errno code is returned
 *	on a failure to set up the device, or if the name is a duplicate.
 *
 *	Callers must hold the rtnl semaphore. You may want
 *	register_netdev() instead of this.
 *
 *	BUGS:
 *	The locking appears insufficient to guarantee two parallel registers
 *	will not get the same name.
 */

int register_netdevice(struct net_device *dev)
{
	int ret;
7470
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
7471 7472 7473 7474

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

7475 7476
	might_sleep();

L
Linus Torvalds 已提交
7477 7478
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
7479
	BUG_ON(!net);
L
Linus Torvalds 已提交
7480

7481
	spin_lock_init(&dev->addr_list_lock);
7482
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
7483

7484
	ret = dev_get_valid_name(net, dev, dev->name);
7485 7486 7487
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
7488
	/* Init, if this function is available */
7489 7490
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
7491 7492 7493
		if (ret) {
			if (ret > 0)
				ret = -EIO;
7494
			goto out;
L
Linus Torvalds 已提交
7495 7496
		}
	}
7497

7498 7499
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
7500 7501 7502 7503 7504 7505 7506
	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
		ret = -EINVAL;
		goto err_uninit;
	}

7507 7508 7509 7510 7511 7512
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

7513 7514 7515 7516
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
7517 7518
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
7519

7520
	if (!(dev->flags & IFF_LOOPBACK))
7521
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
7522

7523 7524 7525 7526 7527
	/* If IPv4 TCP segmentation offload is supported we should also
	 * allow the device to enable segmenting the frame with the option
	 * of ignoring a static IP ID value.  This doesn't enable the
	 * feature itself but allows the user to enable it later.
	 */
7528 7529
	if (dev->hw_features & NETIF_F_TSO)
		dev->hw_features |= NETIF_F_TSO_MANGLEID;
7530 7531 7532 7533 7534 7535
	if (dev->vlan_features & NETIF_F_TSO)
		dev->vlan_features |= NETIF_F_TSO_MANGLEID;
	if (dev->mpls_features & NETIF_F_TSO)
		dev->mpls_features |= NETIF_F_TSO_MANGLEID;
	if (dev->hw_enc_features & NETIF_F_TSO)
		dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
7536

7537
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
7538
	 */
7539
	dev->vlan_features |= NETIF_F_HIGHDMA;
7540

7541 7542
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
7543
	dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
7544

S
Simon Horman 已提交
7545 7546 7547 7548
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

7549 7550 7551 7552 7553
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

7554
	ret = netdev_register_kobject(dev);
7555
	if (ret)
7556
		goto err_uninit;
7557 7558
	dev->reg_state = NETREG_REGISTERED;

7559
	__netdev_update_features(dev);
7560

L
Linus Torvalds 已提交
7561 7562 7563 7564 7565 7566 7567
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

7568 7569
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
7570 7571
	dev_init_scheduler(dev);
	dev_hold(dev);
7572
	list_netdevice(dev);
7573
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
7574

7575 7576 7577 7578 7579 7580 7581
	/* If the device has permanent device address, driver should
	 * set dev_addr and also addr_assign_type should be set to
	 * NET_ADDR_PERM (default value).
	 */
	if (dev->addr_assign_type == NET_ADDR_PERM)
		memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);

L
Linus Torvalds 已提交
7582
	/* Notify protocols, that a new device appeared. */
7583
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
7584
	ret = notifier_to_errno(ret);
7585 7586 7587 7588
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
7589 7590 7591 7592
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7593 7594
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7595
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
7596 7597 7598

out:
	return ret;
7599 7600

err_uninit:
7601 7602
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
7603 7604
	if (dev->priv_destructor)
		dev->priv_destructor(dev);
7605
	goto out;
L
Linus Torvalds 已提交
7606
}
E
Eric Dumazet 已提交
7607
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
7608

7609 7610 7611 7612 7613 7614 7615 7616 7617 7618 7619 7620 7621 7622 7623 7624 7625 7626 7627 7628 7629 7630 7631 7632 7633 7634 7635 7636 7637 7638 7639
/**
 *	init_dummy_netdev	- init a dummy network device for NAPI
 *	@dev: device to init
 *
 *	This takes a network device structure and initialize the minimum
 *	amount of fields so it can be used to schedule NAPI polls without
 *	registering a full blown interface. This is to be used by drivers
 *	that need to tie several hardware interfaces to a single NAPI
 *	poll scheduler due to HW limitations.
 */
int init_dummy_netdev(struct net_device *dev)
{
	/* Clear everything. Note we don't initialize spinlocks
	 * are they aren't supposed to be taken by any of the
	 * NAPI code and this dummy netdev is supposed to be
	 * only ever used for NAPI polls
	 */
	memset(dev, 0, sizeof(struct net_device));

	/* make sure we BUG if trying to hit standard
	 * register/unregister code path
	 */
	dev->reg_state = NETREG_DUMMY;

	/* NAPI wants this */
	INIT_LIST_HEAD(&dev->napi_list);

	/* a dummy interface is started by default */
	set_bit(__LINK_STATE_PRESENT, &dev->state);
	set_bit(__LINK_STATE_START, &dev->state);

E
Eric Dumazet 已提交
7640 7641 7642 7643 7644
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

7645 7646 7647 7648 7649
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
7650 7651 7652 7653 7654 7655 7656 7657 7658
/**
 *	register_netdev	- register a network device
 *	@dev: device to register
 *
 *	Take a completed network device structure and add it to the kernel
 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
 *	chain. 0 is returned on success. A negative errno code is returned
 *	on a failure to set up the device, or if the name is a duplicate.
 *
7659
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
7660 7661 7662 7663 7664 7665 7666 7667 7668 7669 7670 7671 7672 7673
 *	and expands the device name if you passed a format string to
 *	alloc_netdev.
 */
int register_netdev(struct net_device *dev)
{
	int err;

	rtnl_lock();
	err = register_netdevice(dev);
	rtnl_unlock();
	return err;
}
EXPORT_SYMBOL(register_netdev);

E
Eric Dumazet 已提交
7674 7675 7676 7677 7678 7679 7680 7681 7682 7683
int netdev_refcnt_read(const struct net_device *dev)
{
	int i, refcnt = 0;

	for_each_possible_cpu(i)
		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
	return refcnt;
}
EXPORT_SYMBOL(netdev_refcnt_read);

7684
/**
L
Linus Torvalds 已提交
7685
 * netdev_wait_allrefs - wait until all references are gone.
7686
 * @dev: target net_device
L
Linus Torvalds 已提交
7687 7688 7689 7690 7691 7692 7693
 *
 * This is called when unregistering network devices.
 *
 * Any protocol or device that holds a reference should register
 * for netdevice notification, and cleanup and put back the
 * reference if they receive an UNREGISTER event.
 * We can get stuck here if buggy protocols don't correctly
7694
 * call dev_put.
L
Linus Torvalds 已提交
7695 7696 7697 7698
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
7699
	int refcnt;
L
Linus Torvalds 已提交
7700

7701 7702
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
7703
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
7704 7705 7706
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
7707
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
7708
			rtnl_lock();
L
Linus Torvalds 已提交
7709 7710

			/* Rebroadcast unregister notification */
7711
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
7712

7713
			__rtnl_unlock();
7714
			rcu_barrier();
7715 7716
			rtnl_lock();

7717
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
7718 7719 7720 7721 7722 7723 7724 7725 7726 7727 7728
			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
				     &dev->state)) {
				/* We must not have linkwatch events
				 * pending on unregister. If this
				 * happens, we simply run the queue
				 * unscheduled, resulting in a noop
				 * for this device.
				 */
				linkwatch_run_queue();
			}

7729
			__rtnl_unlock();
L
Linus Torvalds 已提交
7730 7731 7732 7733 7734 7735

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
7736 7737
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
7738
		if (time_after(jiffies, warning_time + 10 * HZ)) {
7739 7740
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
7741 7742 7743 7744 7745 7746 7747 7748 7749 7750 7751 7752 7753 7754 7755 7756 7757 7758 7759
			warning_time = jiffies;
		}
	}
}

/* The sequence is:
 *
 *	rtnl_lock();
 *	...
 *	register_netdevice(x1);
 *	register_netdevice(x2);
 *	...
 *	unregister_netdevice(y1);
 *	unregister_netdevice(y2);
 *      ...
 *	rtnl_unlock();
 *	free_netdev(y1);
 *	free_netdev(y2);
 *
H
Herbert Xu 已提交
7760
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
7761
 * This allows us to deal with problems:
7762
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
7763 7764 7765
 *    without deadlocking with linkwatch via keventd.
 * 2) Since we run with the RTNL semaphore not held, we can sleep
 *    safely in order to wait for the netdev refcnt to drop to zero.
H
Herbert Xu 已提交
7766 7767 7768
 *
 * We must not return until all unregister events added during
 * the interval the lock was held have been completed.
L
Linus Torvalds 已提交
7769 7770 7771
 */
void netdev_run_todo(void)
{
7772
	struct list_head list;
L
Linus Torvalds 已提交
7773 7774

	/* Snapshot list, allow later requests */
7775
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
7776 7777

	__rtnl_unlock();
7778

7779 7780

	/* Wait for rcu callbacks to finish before next phase */
7781 7782 7783
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
7784 7785
	while (!list_empty(&list)) {
		struct net_device *dev
7786
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
7787 7788
		list_del(&dev->todo_list);

7789
		rtnl_lock();
7790
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7791
		__rtnl_unlock();
7792

7793
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
7794
			pr_err("network todo '%s' but state %d\n",
7795 7796 7797 7798
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
7799

7800
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
7801

7802
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
7803

7804
		/* paranoia */
E
Eric Dumazet 已提交
7805
		BUG_ON(netdev_refcnt_read(dev));
7806 7807
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
7808 7809
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
7810
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
7811

7812 7813 7814 7815
		if (dev->priv_destructor)
			dev->priv_destructor(dev);
		if (dev->needs_free_netdev)
			free_netdev(dev);
7816

7817 7818 7819 7820 7821 7822
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

7823 7824
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
7825 7826 7827
	}
}

7828 7829 7830 7831
/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
 * all the same fields in the same order as net_device_stats, with only
 * the type differing, but rtnl_link_stats64 may have additional fields
 * at the end for newer counters.
7832
 */
7833 7834
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
7835 7836
{
#if BITS_PER_LONG == 64
7837
	BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats));
7838
	memcpy(stats64, netdev_stats, sizeof(*netdev_stats));
7839 7840 7841
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + sizeof(*netdev_stats), 0,
	       sizeof(*stats64) - sizeof(*netdev_stats));
7842
#else
7843
	size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long);
7844 7845 7846
	const unsigned long *src = (const unsigned long *)netdev_stats;
	u64 *dst = (u64 *)stats64;

7847
	BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
7848 7849
	for (i = 0; i < n; i++)
		dst[i] = src[i];
7850 7851 7852
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + n * sizeof(u64), 0,
	       sizeof(*stats64) - n * sizeof(u64));
7853 7854
#endif
}
7855
EXPORT_SYMBOL(netdev_stats_to_stats64);
7856

7857 7858 7859
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
7860
 *	@storage: place to store stats
7861
 *
7862 7863 7864 7865
 *	Get network statistics from device. Return @storage.
 *	The device driver may provide its own method by setting
 *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
 *	otherwise the internal statistics structure is used.
7866
 */
7867 7868
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
7869
{
7870 7871
	const struct net_device_ops *ops = dev->netdev_ops;

7872 7873
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
7874 7875
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
7876
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
7877 7878
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
7879
	}
7880 7881 7882
	storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped);
	storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped);
	storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler);
7883
	return storage;
R
Rusty Russell 已提交
7884
}
7885
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
7886

7887
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
7888
{
7889
	struct netdev_queue *queue = dev_ingress_queue(dev);
7890

7891 7892 7893 7894 7895 7896 7897
#ifdef CONFIG_NET_CLS_ACT
	if (queue)
		return queue;
	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
	if (!queue)
		return NULL;
	netdev_init_one_queue(dev, queue, NULL);
E
Eric Dumazet 已提交
7898
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
7899 7900 7901 7902
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
7903 7904
}

7905 7906
static const struct ethtool_ops default_ethtool_ops;

7907 7908 7909 7910 7911 7912 7913 7914
void netdev_set_default_ethtool_ops(struct net_device *dev,
				    const struct ethtool_ops *ops)
{
	if (dev->ethtool_ops == &default_ethtool_ops)
		dev->ethtool_ops = ops;
}
EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);

7915 7916 7917 7918
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
7919
	kvfree(addr);
7920 7921
}

L
Linus Torvalds 已提交
7922
/**
7923 7924 7925 7926 7927 7928 7929 7930 7931 7932 7933
 * alloc_netdev_mqs - allocate network device
 * @sizeof_priv: size of private data to allocate space for
 * @name: device name format string
 * @name_assign_type: origin of device name
 * @setup: callback to initialize device
 * @txqs: the number of TX subqueues to allocate
 * @rxqs: the number of RX subqueues to allocate
 *
 * Allocates a struct net_device with private data area for driver use
 * and performs basic initialization.  Also allocates subqueue structs
 * for each queue on the device.
L
Linus Torvalds 已提交
7934
 */
T
Tom Herbert 已提交
7935
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
7936
		unsigned char name_assign_type,
T
Tom Herbert 已提交
7937 7938
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
7939 7940
{
	struct net_device *dev;
7941
	size_t alloc_size;
7942
	struct net_device *p;
L
Linus Torvalds 已提交
7943

7944 7945
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
7946
	if (txqs < 1) {
7947
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
7948 7949 7950
		return NULL;
	}

7951
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
7952
	if (rxqs < 1) {
7953
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
7954 7955 7956 7957
		return NULL;
	}
#endif

7958
	alloc_size = sizeof(struct net_device);
7959 7960
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
7961
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
7962 7963 7964
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
7965
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
7966

7967
	p = kvzalloc(alloc_size, GFP_KERNEL | __GFP_REPEAT);
7968
	if (!p)
L
Linus Torvalds 已提交
7969 7970
		return NULL;

7971
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
7972
	dev->padded = (char *)dev - (char *)p;
7973

E
Eric Dumazet 已提交
7974 7975
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
7976
		goto free_dev;
7977 7978

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
7979
		goto free_pcpu;
7980

7981
	dev_mc_init(dev);
7982
	dev_uc_init(dev);
J
Jiri Pirko 已提交
7983

7984
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
7985

7986
	dev->gso_max_size = GSO_MAX_SIZE;
7987
	dev->gso_max_segs = GSO_MAX_SEGS;
7988 7989 7990

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
7991
	INIT_LIST_HEAD(&dev->close_list);
7992
	INIT_LIST_HEAD(&dev->link_watch_list);
7993 7994
	INIT_LIST_HEAD(&dev->adj_list.upper);
	INIT_LIST_HEAD(&dev->adj_list.lower);
7995 7996
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
7997 7998 7999
#ifdef CONFIG_NET_SCHED
	hash_init(dev->qdisc_hash);
#endif
8000
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
8001 8002
	setup(dev);

8003
	if (!dev->tx_queue_len) {
8004
		dev->priv_flags |= IFF_NO_QUEUE;
8005
		dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
8006
	}
8007

T
Tom Herbert 已提交
8008 8009
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
8010
	if (netif_alloc_netdev_queues(dev))
8011
		goto free_all;
8012

8013
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
8014 8015
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
8016
	if (netif_alloc_rx_queues(dev))
8017
		goto free_all;
E
Eric Dumazet 已提交
8018
#endif
T
Tom Herbert 已提交
8019

L
Linus Torvalds 已提交
8020
	strcpy(dev->name, name);
8021
	dev->name_assign_type = name_assign_type;
8022
	dev->group = INIT_NETDEV_GROUP;
8023 8024
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
8025 8026 8027

	nf_hook_ingress_init(dev);

L
Linus Torvalds 已提交
8028
	return dev;
8029

8030 8031 8032 8033
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
8034 8035
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
8036 8037
free_dev:
	netdev_freemem(dev);
8038
	return NULL;
L
Linus Torvalds 已提交
8039
}
T
Tom Herbert 已提交
8040
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
8041 8042

/**
8043 8044
 * free_netdev - free network device
 * @dev: device
L
Linus Torvalds 已提交
8045
 *
8046 8047 8048 8049
 * This function does the last stage of destroying an allocated device
 * interface. The reference to the device object is released. If this
 * is the last reference then it will be freed.Must be called in process
 * context.
L
Linus Torvalds 已提交
8050 8051 8052
 */
void free_netdev(struct net_device *dev)
{
8053
	struct napi_struct *p, *n;
D
David S. Miller 已提交
8054
	struct bpf_prog *prog;
8055

8056
	might_sleep();
8057
	netif_free_tx_queues(dev);
8058
#ifdef CONFIG_SYSFS
8059
	kvfree(dev->_rx);
T
Tom Herbert 已提交
8060
#endif
8061

8062
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
8063

8064 8065 8066
	/* Flush device addresses */
	dev_addr_flush(dev);

8067 8068 8069
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
8070 8071 8072
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

D
David S. Miller 已提交
8073 8074 8075 8076 8077 8078
	prog = rcu_dereference_protected(dev->xdp_prog, 1);
	if (prog) {
		bpf_prog_put(prog);
		static_key_slow_dec(&generic_xdp_needed);
	}

S
Stephen Hemminger 已提交
8079
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
8080
	if (dev->reg_state == NETREG_UNINITIALIZED) {
8081
		netdev_freemem(dev);
L
Linus Torvalds 已提交
8082 8083 8084 8085 8086 8087
		return;
	}

	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
	dev->reg_state = NETREG_RELEASED;

8088 8089
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
8090
}
E
Eric Dumazet 已提交
8091
EXPORT_SYMBOL(free_netdev);
8092

8093 8094 8095 8096 8097 8098
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
8099
void synchronize_net(void)
L
Linus Torvalds 已提交
8100 8101
{
	might_sleep();
8102 8103 8104 8105
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
8106
}
E
Eric Dumazet 已提交
8107
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
8108 8109

/**
8110
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
8111
 *	@dev: device
8112
 *	@head: list
8113
 *
L
Linus Torvalds 已提交
8114
 *	This function shuts down a device interface and removes it
8115
 *	from the kernel tables.
8116
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
8117 8118 8119 8120 8121
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

8122
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
8123
{
8124 8125
	ASSERT_RTNL();

8126
	if (head) {
8127
		list_move_tail(&dev->unreg_list, head);
8128 8129 8130 8131 8132
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
8133
}
8134
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
8135

8136 8137 8138
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
8139 8140 8141
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
8142 8143 8144 8145 8146 8147 8148 8149 8150
 */
void unregister_netdevice_many(struct list_head *head)
{
	struct net_device *dev;

	if (!list_empty(head)) {
		rollback_registered_many(head);
		list_for_each_entry(dev, head, unreg_list)
			net_set_todo(dev);
8151
		list_del(head);
8152 8153
	}
}
8154
EXPORT_SYMBOL(unregister_netdevice_many);
8155

L
Linus Torvalds 已提交
8156 8157 8158 8159 8160
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
8161
 *	from the kernel tables.
L
Linus Torvalds 已提交
8162 8163 8164 8165 8166 8167 8168 8169 8170 8171 8172 8173 8174
 *
 *	This is just a wrapper for unregister_netdevice that takes
 *	the rtnl semaphore.  In general you want to use this and not
 *	unregister_netdevice.
 */
void unregister_netdev(struct net_device *dev)
{
	rtnl_lock();
	unregister_netdevice(dev);
	rtnl_unlock();
}
EXPORT_SYMBOL(unregister_netdev);

8175 8176 8177 8178 8179 8180 8181 8182 8183 8184 8185 8186 8187 8188 8189 8190 8191 8192 8193 8194 8195 8196 8197 8198 8199 8200 8201 8202 8203 8204 8205
/**
 *	dev_change_net_namespace - move device to different nethost namespace
 *	@dev: device
 *	@net: network namespace
 *	@pat: If not NULL name pattern to try if the current device name
 *	      is already taken in the destination network namespace.
 *
 *	This function shuts down a device interface and moves it
 *	to a new network namespace. On success 0 is returned, on
 *	a failure a netagive errno code is returned.
 *
 *	Callers must hold the rtnl semaphore.
 */

int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
{
	int err;

	ASSERT_RTNL();

	/* Don't allow namespace local devices to be moved. */
	err = -EINVAL;
	if (dev->features & NETIF_F_NETNS_LOCAL)
		goto out;

	/* Ensure the device has been registrered */
	if (dev->reg_state != NETREG_REGISTERED)
		goto out;

	/* Get out if there is nothing todo */
	err = 0;
8206
	if (net_eq(dev_net(dev), net))
8207 8208 8209 8210 8211 8212
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
8213
	if (__dev_get_by_name(net, dev->name)) {
8214 8215 8216
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
8217
		if (dev_get_valid_name(net, dev, pat) < 0)
8218 8219 8220 8221 8222 8223 8224 8225
			goto out;
	}

	/*
	 * And now a mini version of register_netdevice unregister_netdevice.
	 */

	/* If device is running close it first. */
8226
	dev_close(dev);
8227 8228 8229 8230 8231 8232 8233 8234 8235 8236 8237

	/* And unlink it from device chain */
	err = -ENODEV;
	unlist_netdevice(dev);

	synchronize_net();

	/* Shutdown queueing discipline. */
	dev_shutdown(dev);

	/* Notify protocols, that we are about to destroy
8238 8239 8240 8241 8242 8243
	 * this device. They should clean all the things.
	 *
	 * Note that dev->reg_state stays at NETREG_REGISTERED.
	 * This is wanted because this way 8021q and macvlan know
	 * the device is just moving and can keep their slaves up.
	 */
8244
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
8245 8246
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
8247
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
8248 8249 8250 8251

	/*
	 *	Flush the unicast and multicast chains
	 */
8252
	dev_uc_flush(dev);
8253
	dev_mc_flush(dev);
8254

8255 8256
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
8257
	netdev_adjacent_del_links(dev);
8258

8259
	/* Actually switch the network namespace */
8260
	dev_net_set(dev, net);
8261 8262

	/* If there is an ifindex conflict assign a new one */
8263
	if (__dev_get_by_index(net, dev->ifindex))
8264 8265
		dev->ifindex = dev_new_index(net);

8266 8267
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
8268
	netdev_adjacent_add_links(dev);
8269

8270
	/* Fixup kobjects */
8271
	err = device_rename(&dev->dev, dev->name);
8272
	WARN_ON(err);
8273 8274 8275 8276 8277 8278 8279

	/* Add the device back in the hashes */
	list_netdevice(dev);

	/* Notify protocols, that a new device appeared. */
	call_netdevice_notifiers(NETDEV_REGISTER, dev);

8280 8281 8282 8283
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
8284
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
8285

8286 8287 8288 8289 8290
	synchronize_net();
	err = 0;
out:
	return err;
}
8291
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
8292

8293
static int dev_cpu_dead(unsigned int oldcpu)
L
Linus Torvalds 已提交
8294 8295 8296
{
	struct sk_buff **list_skb;
	struct sk_buff *skb;
8297
	unsigned int cpu;
8298
	struct softnet_data *sd, *oldsd, *remsd = NULL;
L
Linus Torvalds 已提交
8299 8300 8301 8302 8303 8304 8305 8306 8307 8308 8309 8310 8311 8312 8313

	local_irq_disable();
	cpu = smp_processor_id();
	sd = &per_cpu(softnet_data, cpu);
	oldsd = &per_cpu(softnet_data, oldcpu);

	/* Find end of our completion_queue. */
	list_skb = &sd->completion_queue;
	while (*list_skb)
		list_skb = &(*list_skb)->next;
	/* Append completion queue from offline CPU. */
	*list_skb = oldsd->completion_queue;
	oldsd->completion_queue = NULL;

	/* Append output queue from offline CPU. */
8314 8315 8316 8317 8318 8319
	if (oldsd->output_queue) {
		*sd->output_queue_tailp = oldsd->output_queue;
		sd->output_queue_tailp = oldsd->output_queue_tailp;
		oldsd->output_queue = NULL;
		oldsd->output_queue_tailp = &oldsd->output_queue;
	}
E
Eric Dumazet 已提交
8320 8321 8322 8323 8324 8325 8326 8327 8328 8329 8330 8331 8332 8333
	/* Append NAPI poll list from offline CPU, with one exception :
	 * process_backlog() must be called by cpu owning percpu backlog.
	 * We properly handle process_queue & input_pkt_queue later.
	 */
	while (!list_empty(&oldsd->poll_list)) {
		struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
							    struct napi_struct,
							    poll_list);

		list_del_init(&napi->poll_list);
		if (napi->poll == process_backlog)
			napi->state = 0;
		else
			____napi_schedule(sd, napi);
8334
	}
L
Linus Torvalds 已提交
8335 8336 8337 8338

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

8339 8340 8341 8342 8343 8344 8345
#ifdef CONFIG_RPS
	remsd = oldsd->rps_ipi_list;
	oldsd->rps_ipi_list = NULL;
#endif
	/* send out pending IPI's on offline CPU */
	net_rps_send_ipi(remsd);

L
Linus Torvalds 已提交
8346
	/* Process offline CPU's input_pkt_queue */
8347
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
8348
		netif_rx_ni(skb);
8349
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
8350
	}
E
Eric Dumazet 已提交
8351
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
8352
		netif_rx_ni(skb);
8353 8354
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
8355

8356
	return 0;
L
Linus Torvalds 已提交
8357 8358
}

8359
/**
8360 8361 8362 8363
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
8364 8365
 *
 *	Computes a new feature set after adding a device with feature set
8366 8367
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
8368
 */
8369 8370
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
8371
{
8372
	if (mask & NETIF_F_HW_CSUM)
8373
		mask |= NETIF_F_CSUM_MASK;
8374
	mask |= NETIF_F_VLAN_CHALLENGED;
8375

8376
	all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
8377
	all &= one | ~NETIF_F_ALL_FOR_ALL;
8378

8379
	/* If one device supports hw checksumming, set for all. */
8380 8381
	if (all & NETIF_F_HW_CSUM)
		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
8382 8383 8384

	return all;
}
8385
EXPORT_SYMBOL(netdev_increment_features);
8386

8387
static struct hlist_head * __net_init netdev_create_hash(void)
8388 8389 8390 8391 8392 8393 8394 8395 8396 8397 8398 8399
{
	int i;
	struct hlist_head *hash;

	hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
	if (hash != NULL)
		for (i = 0; i < NETDEV_HASHENTRIES; i++)
			INIT_HLIST_HEAD(&hash[i]);

	return hash;
}

8400
/* Initialize per network namespace state */
8401
static int __net_init netdev_init(struct net *net)
8402
{
8403 8404
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
8405

8406 8407 8408
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
8409

8410 8411 8412
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
8413 8414

	return 0;
8415 8416 8417 8418 8419

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
8420 8421
}

8422 8423 8424 8425 8426 8427
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
8428
const char *netdev_drivername(const struct net_device *dev)
8429
{
8430 8431
	const struct device_driver *driver;
	const struct device *parent;
8432
	const char *empty = "";
8433 8434 8435

	parent = dev->dev.parent;
	if (!parent)
8436
		return empty;
8437 8438 8439

	driver = parent->driver;
	if (driver && driver->name)
8440 8441
		return driver->name;
	return empty;
8442 8443
}

8444 8445
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
8446
{
8447
	if (dev && dev->dev.parent) {
8448 8449 8450 8451 8452 8453 8454
		dev_printk_emit(level[1] - '0',
				dev->dev.parent,
				"%s %s %s%s: %pV",
				dev_driver_string(dev->dev.parent),
				dev_name(dev->dev.parent),
				netdev_name(dev), netdev_reg_state(dev),
				vaf);
8455
	} else if (dev) {
8456 8457
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
8458
	} else {
8459
		printk("%s(NULL net_device): %pV", level, vaf);
8460
	}
8461 8462
}

8463 8464
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
8465 8466 8467 8468 8469 8470 8471 8472 8473
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

	vaf.fmt = format;
	vaf.va = &args;

8474
	__netdev_printk(level, dev, &vaf);
8475

8476 8477 8478 8479 8480
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
8481
void func(const struct net_device *dev, const char *fmt, ...)	\
8482 8483 8484 8485 8486 8487 8488 8489 8490
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
8491
	__netdev_printk(level, dev, &vaf);			\
8492
								\
8493 8494 8495 8496 8497 8498 8499 8500 8501 8502 8503 8504
	va_end(args);						\
}								\
EXPORT_SYMBOL(func);

define_netdev_printk_level(netdev_emerg, KERN_EMERG);
define_netdev_printk_level(netdev_alert, KERN_ALERT);
define_netdev_printk_level(netdev_crit, KERN_CRIT);
define_netdev_printk_level(netdev_err, KERN_ERR);
define_netdev_printk_level(netdev_warn, KERN_WARNING);
define_netdev_printk_level(netdev_notice, KERN_NOTICE);
define_netdev_printk_level(netdev_info, KERN_INFO);

8505
static void __net_exit netdev_exit(struct net *net)
8506 8507 8508 8509 8510
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

8511
static struct pernet_operations __net_initdata netdev_net_ops = {
8512 8513 8514 8515
	.init = netdev_init,
	.exit = netdev_exit,
};

8516
static void __net_exit default_device_exit(struct net *net)
8517
{
8518
	struct net_device *dev, *aux;
8519
	/*
8520
	 * Push all migratable network devices back to the
8521 8522 8523
	 * initial network namespace
	 */
	rtnl_lock();
8524
	for_each_netdev_safe(net, dev, aux) {
8525
		int err;
8526
		char fb_name[IFNAMSIZ];
8527 8528 8529 8530 8531

		/* Ignore unmoveable devices (i.e. loopback) */
		if (dev->features & NETIF_F_NETNS_LOCAL)
			continue;

8532 8533 8534
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
8535

L
Lucas De Marchi 已提交
8536
		/* Push remaining network devices to init_net */
8537 8538
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
8539
		if (err) {
8540 8541
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
8542
			BUG();
8543 8544 8545 8546 8547
		}
	}
	rtnl_unlock();
}

8548 8549 8550 8551 8552 8553 8554
static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
{
	/* Return with the rtnl_lock held when there are no network
	 * devices unregistering in any network namespace in net_list.
	 */
	struct net *net;
	bool unregistering;
8555
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
8556

8557
	add_wait_queue(&netdev_unregistering_wq, &wait);
8558 8559 8560 8561 8562 8563 8564 8565 8566 8567 8568 8569
	for (;;) {
		unregistering = false;
		rtnl_lock();
		list_for_each_entry(net, net_list, exit_list) {
			if (net->dev_unreg_count > 0) {
				unregistering = true;
				break;
			}
		}
		if (!unregistering)
			break;
		__rtnl_unlock();
8570 8571

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
8572
	}
8573
	remove_wait_queue(&netdev_unregistering_wq, &wait);
8574 8575
}

8576 8577 8578
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
8579
	 * namespace.  Do this in the reverse order of registration.
8580 8581 8582 8583 8584 8585 8586
	 * Do this across as many network namespaces as possible to
	 * improve batching efficiency.
	 */
	struct net_device *dev;
	struct net *net;
	LIST_HEAD(dev_kill_list);

8587 8588 8589 8590 8591 8592 8593 8594 8595 8596 8597 8598
	/* To prevent network device cleanup code from dereferencing
	 * loopback devices or network devices that have been freed
	 * wait here for all pending unregistrations to complete,
	 * before unregistring the loopback device and allowing the
	 * network namespace be freed.
	 *
	 * The netdev todo list containing all network devices
	 * unregistrations that happen in default_device_exit_batch
	 * will run in the rtnl_unlock() at the end of
	 * default_device_exit_batch.
	 */
	rtnl_lock_unregistering(net_list);
8599 8600
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
8601
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
8602 8603 8604 8605 8606 8607 8608 8609 8610
				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
			else
				unregister_netdevice_queue(dev, &dev_kill_list);
		}
	}
	unregister_netdevice_many(&dev_kill_list);
	rtnl_unlock();
}

8611
static struct pernet_operations __net_initdata default_device_ops = {
8612
	.exit = default_device_exit,
8613
	.exit_batch = default_device_exit_batch,
8614 8615
};

L
Linus Torvalds 已提交
8616 8617 8618 8619 8620 8621 8622 8623 8624 8625 8626 8627 8628 8629 8630 8631 8632 8633 8634 8635
/*
 *	Initialize the DEV module. At boot time this walks the device list and
 *	unhooks any devices that fail to initialise (normally hardware not
 *	present) and leaves us with a valid list of present and active devices.
 *
 */

/*
 *       This is called single threaded during boot, so no need
 *       to take the rtnl semaphore.
 */
static int __init net_dev_init(void)
{
	int i, rc = -ENOMEM;

	BUG_ON(!dev_boot_phase);

	if (dev_proc_init())
		goto out;

8636
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
8637 8638 8639
		goto out;

	INIT_LIST_HEAD(&ptype_all);
8640
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
8641 8642
		INIT_LIST_HEAD(&ptype_base[i]);

8643 8644
	INIT_LIST_HEAD(&offload_base);

8645 8646
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
8647 8648 8649 8650 8651

	/*
	 *	Initialise the packet receive queues.
	 */

8652
	for_each_possible_cpu(i) {
8653
		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
E
Eric Dumazet 已提交
8654
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
8655

8656 8657
		INIT_WORK(flush, flush_backlog);

E
Eric Dumazet 已提交
8658
		skb_queue_head_init(&sd->input_pkt_queue);
8659
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
8660
		INIT_LIST_HEAD(&sd->poll_list);
8661
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
8662
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
8663 8664 8665
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
8666
#endif
T
Tom Herbert 已提交
8667

E
Eric Dumazet 已提交
8668 8669
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
8670 8671 8672 8673
	}

	dev_boot_phase = 0;

8674 8675 8676 8677 8678 8679 8680 8681 8682 8683 8684 8685 8686 8687 8688
	/* The loopback device is special if any other network devices
	 * is present in a network namespace the loopback device must
	 * be present. Since we now dynamically allocate and free the
	 * loopback device ensure this invariant is maintained by
	 * keeping the loopback device as the first device on the
	 * list of network devices.  Ensuring the loopback devices
	 * is the first device that appears and the last network device
	 * that disappears.
	 */
	if (register_pernet_device(&loopback_net_ops))
		goto out;

	if (register_pernet_device(&default_device_ops))
		goto out;

8689 8690
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
8691

8692 8693 8694
	rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead",
				       NULL, dev_cpu_dead);
	WARN_ON(rc < 0);
L
Linus Torvalds 已提交
8695 8696 8697 8698 8699 8700
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);