skbuff.h 69.0 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
/*
 *	Definitions for the 'struct sk_buff' memory handlers.
 *
 *	Authors:
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *		Florian La Roche, <rzsfl@rz.uni-sb.de>
 *
 *	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.
 */

#ifndef _LINUX_SKBUFF_H
#define _LINUX_SKBUFF_H

#include <linux/kernel.h>
18
#include <linux/kmemcheck.h>
L
Linus Torvalds 已提交
19 20 21 22
#include <linux/compiler.h>
#include <linux/time.h>
#include <linux/cache.h>

A
Arun Sharma 已提交
23
#include <linux/atomic.h>
L
Linus Torvalds 已提交
24 25 26
#include <asm/types.h>
#include <linux/spinlock.h>
#include <linux/net.h>
27
#include <linux/textsearch.h>
L
Linus Torvalds 已提交
28
#include <net/checksum.h>
29
#include <linux/rcupdate.h>
30
#include <linux/dmaengine.h>
31
#include <linux/hrtimer.h>
32
#include <linux/dma-mapping.h>
33
#include <linux/netdev_features.h>
L
Linus Torvalds 已提交
34

35
/* Don't change this without changing skb_csum_unnecessary! */
L
Linus Torvalds 已提交
36
#define CHECKSUM_NONE 0
37 38 39
#define CHECKSUM_UNNECESSARY 1
#define CHECKSUM_COMPLETE 2
#define CHECKSUM_PARTIAL 3
L
Linus Torvalds 已提交
40 41 42

#define SKB_DATA_ALIGN(X)	(((X) + (SMP_CACHE_BYTES - 1)) & \
				 ~(SMP_CACHE_BYTES - 1))
43
#define SKB_WITH_OVERHEAD(X)	\
44
	((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
45 46
#define SKB_MAX_ORDER(X, ORDER) \
	SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
L
Linus Torvalds 已提交
47 48 49
#define SKB_MAX_HEAD(X)		(SKB_MAX_ORDER((X), 0))
#define SKB_MAX_ALLOC		(SKB_MAX_ORDER(0, 2))

E
Eric Dumazet 已提交
50 51 52 53 54
/* return minimum truesize of one skb containing X bytes of data */
#define SKB_TRUESIZE(X) ((X) +						\
			 SKB_DATA_ALIGN(sizeof(struct sk_buff)) +	\
			 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))

L
Linus Torvalds 已提交
55 56 57 58 59 60 61 62 63 64 65
/* A. Checksumming of received packets by device.
 *
 *	NONE: device failed to checksum this packet.
 *		skb->csum is undefined.
 *
 *	UNNECESSARY: device parsed packet and wouldbe verified checksum.
 *		skb->csum is undefined.
 *	      It is bad option, but, unfortunately, many of vendors do this.
 *	      Apparently with secret goal to sell you new device, when you
 *	      will add new protocol to your host. F.e. IPv6. 8)
 *
66
 *	COMPLETE: the most generic way. Device supplied checksum of _all_
L
Linus Torvalds 已提交
67 68
 *	    the packet as seen by netif_rx in skb->csum.
 *	    NOTE: Even if device supports only some protocols, but
69
 *	    is able to produce some skb->csum, it MUST use COMPLETE,
L
Linus Torvalds 已提交
70 71
 *	    not UNNECESSARY.
 *
72 73 74 75 76 77 78
 *	PARTIAL: identical to the case for output below.  This may occur
 *	    on a packet received directly from another Linux OS, e.g.,
 *	    a virtualised Linux kernel on the same host.  The packet can
 *	    be treated in the same way as UNNECESSARY except that on
 *	    output (i.e., forwarding) the checksum must be filled in
 *	    by the OS or the hardware.
 *
L
Linus Torvalds 已提交
79 80 81 82
 * B. Checksumming on output.
 *
 *	NONE: skb is checksummed by protocol or csum is not required.
 *
83
 *	PARTIAL: device is required to csum packet as seen by hard_start_xmit
84 85
 *	from skb->csum_start to the end and to record the checksum
 *	at skb->csum_start + skb->csum_offset.
L
Linus Torvalds 已提交
86 87 88 89 90 91 92 93 94
 *
 *	Device must show its capabilities in dev->features, set
 *	at device setup time.
 *	NETIF_F_HW_CSUM	- it is clever device, it is able to checksum
 *			  everything.
 *	NETIF_F_IP_CSUM - device is dumb. It is able to csum only
 *			  TCP/UDP over IPv4. Sigh. Vendors like this
 *			  way by an unknown reason. Though, see comment above
 *			  about CHECKSUM_UNNECESSARY. 8)
95
 *	NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead.
L
Linus Torvalds 已提交
96 97 98 99 100
 *
 *	Any questions? No questions, good. 		--ANK
 */

struct net_device;
101
struct scatterlist;
J
Jens Axboe 已提交
102
struct pipe_inode_info;
L
Linus Torvalds 已提交
103

104
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
L
Linus Torvalds 已提交
105 106 107
struct nf_conntrack {
	atomic_t use;
};
108
#endif
L
Linus Torvalds 已提交
109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130

#ifdef CONFIG_BRIDGE_NETFILTER
struct nf_bridge_info {
	atomic_t use;
	struct net_device *physindev;
	struct net_device *physoutdev;
	unsigned int mask;
	unsigned long data[32 / sizeof(unsigned long)];
};
#endif

struct sk_buff_head {
	/* These two members must be first. */
	struct sk_buff	*next;
	struct sk_buff	*prev;

	__u32		qlen;
	spinlock_t	lock;
};

struct sk_buff;

131 132 133 134
/* To allow 64K frame to be packed as single skb without frag_list. Since
 * GRO uses frags we allocate at least 16 regardless of page size.
 */
#if (65536/PAGE_SIZE + 2) < 16
135
#define MAX_SKB_FRAGS 16UL
136
#else
L
Linus Torvalds 已提交
137
#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2)
138
#endif
L
Linus Torvalds 已提交
139 140 141 142

typedef struct skb_frag_struct skb_frag_t;

struct skb_frag_struct {
143 144 145
	struct {
		struct page *p;
	} page;
146
#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
147 148
	__u32 page_offset;
	__u32 size;
149 150 151 152
#else
	__u16 page_offset;
	__u16 size;
#endif
L
Linus Torvalds 已提交
153 154
};

E
Eric Dumazet 已提交
155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174
static inline unsigned int skb_frag_size(const skb_frag_t *frag)
{
	return frag->size;
}

static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size)
{
	frag->size = size;
}

static inline void skb_frag_size_add(skb_frag_t *frag, int delta)
{
	frag->size += delta;
}

static inline void skb_frag_size_sub(skb_frag_t *frag, int delta)
{
	frag->size -= delta;
}

175 176 177
#define HAVE_HW_TIME_STAMP

/**
178
 * struct skb_shared_hwtstamps - hardware time stamps
179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204
 * @hwtstamp:	hardware time stamp transformed into duration
 *		since arbitrary point in time
 * @syststamp:	hwtstamp transformed to system time base
 *
 * Software time stamps generated by ktime_get_real() are stored in
 * skb->tstamp. The relation between the different kinds of time
 * stamps is as follows:
 *
 * syststamp and tstamp can be compared against each other in
 * arbitrary combinations.  The accuracy of a
 * syststamp/tstamp/"syststamp from other device" comparison is
 * limited by the accuracy of the transformation into system time
 * base. This depends on the device driver and its underlying
 * hardware.
 *
 * hwtstamps can only be compared against other hwtstamps from
 * the same device.
 *
 * This structure is attached to packets as part of the
 * &skb_shared_info. Use skb_hwtstamps() to get a pointer.
 */
struct skb_shared_hwtstamps {
	ktime_t	hwtstamp;
	ktime_t	syststamp;
};

205 206 207 208 209 210 211 212 213 214 215 216 217
/* Definitions for tx_flags in struct skb_shared_info */
enum {
	/* generate hardware time stamp */
	SKBTX_HW_TSTAMP = 1 << 0,

	/* generate software time stamp */
	SKBTX_SW_TSTAMP = 1 << 1,

	/* device driver is going to provide hardware time stamp */
	SKBTX_IN_PROGRESS = 1 << 2,

	/* ensure the originating sk reference is available on driver level */
	SKBTX_DRV_NEEDS_SK_REF = 1 << 3,
218 219 220

	/* device driver supports TX zero-copy buffers */
	SKBTX_DEV_ZEROCOPY = 1 << 4,
221 222 223

	/* generate wifi status information (where possible) */
	SKBTX_WIFI_STATUS = 1 << 5,
224 225 226 227 228 229 230 231 232 233 234
};

/*
 * The callback notifies userspace to release buffers when skb DMA is done in
 * lower device, the skb last reference should be 0 when calling this.
 * The desc is used to track userspace buffer index.
 */
struct ubuf_info {
	void (*callback)(void *);
	void *arg;
	unsigned long desc;
235 236
};

L
Linus Torvalds 已提交
237 238 239 240
/* This data is invariant across clones and lives at
 * the end of the header data, ie. at skb->end.
 */
struct skb_shared_info {
B
Benjamin LaHaise 已提交
241
	unsigned short	nr_frags;
242 243 244 245
	unsigned short	gso_size;
	/* Warning: this field is not always filled in (UFO)! */
	unsigned short	gso_segs;
	unsigned short  gso_type;
A
Al Viro 已提交
246
	__be32          ip6_frag_id;
247
	__u8		tx_flags;
L
Linus Torvalds 已提交
248
	struct sk_buff	*frag_list;
249
	struct skb_shared_hwtstamps hwtstamps;
E
Eric Dumazet 已提交
250 251 252 253 254 255

	/*
	 * Warning : all fields before dataref are cleared in __alloc_skb()
	 */
	atomic_t	dataref;

J
Johann Baudy 已提交
256 257 258
	/* Intermediate layers must ensure that destructor_arg
	 * remains valid until skb destructor */
	void *		destructor_arg;
259

260 261
	/* must be last field, see pskb_expand_head() */
	skb_frag_t	frags[MAX_SKB_FRAGS];
L
Linus Torvalds 已提交
262 263 264 265
};

/* We divide dataref into two halves.  The higher 16 bits hold references
 * to the payload part of skb->data.  The lower 16 bits hold references to
266 267
 * the entire skb->data.  A clone of a headerless skb holds the length of
 * the header in skb->hdr_len.
L
Linus Torvalds 已提交
268 269 270 271 272 273 274 275 276 277
 *
 * All users must obey the rule that the skb->data reference count must be
 * greater than or equal to the payload reference count.
 *
 * Holding a reference to the payload part means that the user does not
 * care about modifications to the header part of skb->data.
 */
#define SKB_DATAREF_SHIFT 16
#define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)

278 279 280 281 282 283 284

enum {
	SKB_FCLONE_UNAVAILABLE,
	SKB_FCLONE_ORIG,
	SKB_FCLONE_CLONE,
};

285 286
enum {
	SKB_GSO_TCPV4 = 1 << 0,
H
Herbert Xu 已提交
287
	SKB_GSO_UDP = 1 << 1,
288 289 290

	/* This indicates the skb is from an untrusted source. */
	SKB_GSO_DODGY = 1 << 2,
M
Michael Chan 已提交
291 292

	/* This indicates the tcp segment has CWR set. */
H
Herbert Xu 已提交
293 294 295
	SKB_GSO_TCP_ECN = 1 << 3,

	SKB_GSO_TCPV6 = 1 << 4,
296 297

	SKB_GSO_FCOE = 1 << 5,
298 299
};

300 301 302 303 304 305 306 307 308 309
#if BITS_PER_LONG > 32
#define NET_SKBUFF_DATA_USES_OFFSET 1
#endif

#ifdef NET_SKBUFF_DATA_USES_OFFSET
typedef unsigned int sk_buff_data_t;
#else
typedef unsigned char *sk_buff_data_t;
#endif

310 311 312 313 314
#if defined(CONFIG_NF_DEFRAG_IPV4) || defined(CONFIG_NF_DEFRAG_IPV4_MODULE) || \
    defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
#define NET_SKBUFF_NF_DEFRAG_NEEDED 1
#endif

L
Linus Torvalds 已提交
315 316 317 318
/** 
 *	struct sk_buff - socket buffer
 *	@next: Next buffer in list
 *	@prev: Previous buffer in list
H
Herbert Xu 已提交
319
 *	@tstamp: Time we arrived
320
 *	@sk: Socket we are owned by
L
Linus Torvalds 已提交
321
 *	@dev: Device we arrived on/are leaving by
322
 *	@cb: Control buffer. Free for use by every layer. Put private vars here
E
Eric Dumazet 已提交
323
 *	@_skb_refdst: destination entry (with norefcount bit)
324
 *	@sp: the security path, used for xfrm
L
Linus Torvalds 已提交
325 326 327
 *	@len: Length of actual data
 *	@data_len: Data length
 *	@mac_len: Length of link layer header
328
 *	@hdr_len: writable header length of cloned skb
329 330 331
 *	@csum: Checksum (must include start/offset pair)
 *	@csum_start: Offset from skb->head where checksumming should start
 *	@csum_offset: Offset from csum_start where checksum should be stored
332
 *	@priority: Packet queueing priority
333
 *	@local_df: allow local fragmentation
L
Linus Torvalds 已提交
334
 *	@cloned: Head may be cloned (check refcnt to be sure)
335
 *	@ip_summed: Driver fed us an IP checksum
L
Linus Torvalds 已提交
336
 *	@nohdr: Payload reference only, must not modify header
337
 *	@nfctinfo: Relationship of this skb to the connection
L
Linus Torvalds 已提交
338
 *	@pkt_type: Packet class
339 340
 *	@fclone: skbuff clone status
 *	@ipvs_property: skbuff is owned by ipvs
341 342
 *	@peeked: this packet has been seen already, so stats have been
 *		done for it, don't do them again
343
 *	@nf_trace: netfilter packet trace flag
344 345 346
 *	@protocol: Packet protocol from driver
 *	@destructor: Destruct function
 *	@nfct: Associated connection, if any
R
Randy Dunlap 已提交
347
 *	@nfct_reasm: netfilter conntrack re-assembly pointer
L
Linus Torvalds 已提交
348
 *	@nf_bridge: Saved data about a bridged frame - see br_netfilter.c
349
 *	@skb_iif: ifindex of device we arrived on
L
Linus Torvalds 已提交
350 351
 *	@tc_index: Traffic control index
 *	@tc_verd: traffic control verdict
352 353
 *	@rxhash: the packet hash computed on receive
 *	@queue_mapping: Queue mapping for multiqueue devices
354
 *	@ndisc_nodetype: router type (from link layer)
355
 *	@ooo_okay: allow the mapping of a socket to a queue to be changed
356 357
 *	@l4_rxhash: indicate rxhash is a canonical 4-tuple hash over transport
 *		ports.
358 359
 *	@wifi_acked_valid: wifi_acked was set
 *	@wifi_acked: whether frame was acked on wifi or not
R
Randy Dunlap 已提交
360 361
 *	@dma_cookie: a cookie to one of several possible DMA operations
 *		done by skb DMA functions
362
 *	@secmark: security marking
363 364
 *	@mark: Generic packet mark
 *	@dropcount: total number of sk_receive_queue overflows
365
 *	@vlan_tci: vlan tag control information
366 367 368 369 370 371 372 373 374
 *	@transport_header: Transport layer header
 *	@network_header: Network layer header
 *	@mac_header: Link layer header
 *	@tail: Tail pointer
 *	@end: End pointer
 *	@head: Head of buffer
 *	@data: Data head pointer
 *	@truesize: Buffer size
 *	@users: User count - see {datagram,tcp}.c
L
Linus Torvalds 已提交
375 376 377 378 379 380 381
 */

struct sk_buff {
	/* These two members must be first. */
	struct sk_buff		*next;
	struct sk_buff		*prev;

382
	ktime_t			tstamp;
383 384

	struct sock		*sk;
L
Linus Torvalds 已提交
385 386 387 388 389 390 391 392
	struct net_device	*dev;

	/*
	 * This is the control buffer. It is free to use for every
	 * layer. Please put your private variables there. If you
	 * want to keep them across layers you have to do a skb_clone()
	 * first. This is owned by whoever has the skb queued ATM.
	 */
393
	char			cb[48] __aligned(8);
L
Linus Torvalds 已提交
394

E
Eric Dumazet 已提交
395
	unsigned long		_skb_refdst;
396 397 398
#ifdef CONFIG_XFRM
	struct	sec_path	*sp;
#endif
L
Linus Torvalds 已提交
399
	unsigned int		len,
400 401 402
				data_len;
	__u16			mac_len,
				hdr_len;
A
Al Viro 已提交
403 404
	union {
		__wsum		csum;
405 406 407 408
		struct {
			__u16	csum_start;
			__u16	csum_offset;
		};
A
Al Viro 已提交
409
	};
L
Linus Torvalds 已提交
410
	__u32			priority;
411
	kmemcheck_bitfield_begin(flags1);
412 413 414
	__u8			local_df:1,
				cloned:1,
				ip_summed:2,
415 416
				nohdr:1,
				nfctinfo:3;
417
	__u8			pkt_type:3,
418
				fclone:2,
419
				ipvs_property:1,
420
				peeked:1,
421
				nf_trace:1;
422
	kmemcheck_bitfield_end(flags1);
E
Eric Dumazet 已提交
423
	__be16			protocol;
L
Linus Torvalds 已提交
424 425

	void			(*destructor)(struct sk_buff *skb);
426
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
427
	struct nf_conntrack	*nfct;
428 429
#endif
#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
430 431
	struct sk_buff		*nfct_reasm;
#endif
L
Linus Torvalds 已提交
432 433 434
#ifdef CONFIG_BRIDGE_NETFILTER
	struct nf_bridge_info	*nf_bridge;
#endif
435

436
	int			skb_iif;
L
Linus Torvalds 已提交
437
#ifdef CONFIG_NET_SCHED
438
	__u16			tc_index;	/* traffic control index */
L
Linus Torvalds 已提交
439
#ifdef CONFIG_NET_CLS_ACT
440
	__u16			tc_verd;	/* traffic control verdict */
L
Linus Torvalds 已提交
441 442
#endif
#endif
443

T
Tom Herbert 已提交
444 445
	__u32			rxhash;

446
	__u16			queue_mapping;
447
	kmemcheck_bitfield_begin(flags2);
448
#ifdef CONFIG_IPV6_NDISC_NODETYPE
449
	__u8			ndisc_nodetype:2;
450
#endif
451
	__u8			ooo_okay:1;
452
	__u8			l4_rxhash:1;
453 454 455
	__u8			wifi_acked_valid:1;
	__u8			wifi_acked:1;
	/* 10/12 bit hole (depending on ndisc_nodetype presence) */
456 457
	kmemcheck_bitfield_end(flags2);

458 459 460
#ifdef CONFIG_NET_DMA
	dma_cookie_t		dma_cookie;
#endif
461 462 463
#ifdef CONFIG_NETWORK_SECMARK
	__u32			secmark;
#endif
464 465 466 467
	union {
		__u32		mark;
		__u32		dropcount;
	};
L
Linus Torvalds 已提交
468

469 470
	__u16			vlan_tci;

471 472 473
	sk_buff_data_t		transport_header;
	sk_buff_data_t		network_header;
	sk_buff_data_t		mac_header;
L
Linus Torvalds 已提交
474
	/* These elements must be at the end, see alloc_skb() for details.  */
475
	sk_buff_data_t		tail;
476
	sk_buff_data_t		end;
L
Linus Torvalds 已提交
477
	unsigned char		*head,
478
				*data;
479 480
	unsigned int		truesize;
	atomic_t		users;
L
Linus Torvalds 已提交
481 482 483 484 485 486 487 488 489 490
};

#ifdef __KERNEL__
/*
 *	Handling routines are only of interest to the kernel
 */
#include <linux/slab.h>

#include <asm/system.h>

E
Eric Dumazet 已提交
491 492 493 494 495 496 497 498 499 500 501 502 503
/*
 * skb might have a dst pointer attached, refcounted or not.
 * _skb_refdst low order bit is set if refcount was _not_ taken
 */
#define SKB_DST_NOREF	1UL
#define SKB_DST_PTRMASK	~(SKB_DST_NOREF)

/**
 * skb_dst - returns skb dst_entry
 * @skb: buffer
 *
 * Returns skb dst_entry, regardless of reference taken or not.
 */
E
Eric Dumazet 已提交
504 505
static inline struct dst_entry *skb_dst(const struct sk_buff *skb)
{
E
Eric Dumazet 已提交
506 507 508 509 510 511 512
	/* If refdst was not refcounted, check we still are in a 
	 * rcu_read_lock section
	 */
	WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) &&
		!rcu_read_lock_held() &&
		!rcu_read_lock_bh_held());
	return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK);
E
Eric Dumazet 已提交
513 514
}

E
Eric Dumazet 已提交
515 516 517 518 519 520 521 522
/**
 * skb_dst_set - sets skb dst
 * @skb: buffer
 * @dst: dst entry
 *
 * Sets skb dst, assuming a reference was taken on dst and should
 * be released by skb_dst_drop()
 */
E
Eric Dumazet 已提交
523 524
static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
{
E
Eric Dumazet 已提交
525 526 527
	skb->_skb_refdst = (unsigned long)dst;
}

E
Eric Dumazet 已提交
528
extern void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst);
E
Eric Dumazet 已提交
529 530

/**
L
Lucas De Marchi 已提交
531
 * skb_dst_is_noref - Test if skb dst isn't refcounted
E
Eric Dumazet 已提交
532 533 534 535 536
 * @skb: buffer
 */
static inline bool skb_dst_is_noref(const struct sk_buff *skb)
{
	return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb);
E
Eric Dumazet 已提交
537 538
}

E
Eric Dumazet 已提交
539 540
static inline struct rtable *skb_rtable(const struct sk_buff *skb)
{
E
Eric Dumazet 已提交
541
	return (struct rtable *)skb_dst(skb);
E
Eric Dumazet 已提交
542 543
}

544
extern void kfree_skb(struct sk_buff *skb);
545
extern void consume_skb(struct sk_buff *skb);
L
Linus Torvalds 已提交
546
extern void	       __kfree_skb(struct sk_buff *skb);
547
extern struct sk_buff *__alloc_skb(unsigned int size,
548
				   gfp_t priority, int fclone, int node);
E
Eric Dumazet 已提交
549
extern struct sk_buff *build_skb(void *data);
550
static inline struct sk_buff *alloc_skb(unsigned int size,
A
Al Viro 已提交
551
					gfp_t priority)
552
{
E
Eric Dumazet 已提交
553
	return __alloc_skb(size, priority, 0, NUMA_NO_NODE);
554 555 556
}

static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
A
Al Viro 已提交
557
					       gfp_t priority)
558
{
E
Eric Dumazet 已提交
559
	return __alloc_skb(size, priority, 1, NUMA_NO_NODE);
560 561
}

562
extern void skb_recycle(struct sk_buff *skb);
563
extern bool skb_recycle_check(struct sk_buff *skb, int skb_size);
564

H
Herbert Xu 已提交
565
extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
566
extern int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask);
V
Victor Fusco 已提交
567
extern struct sk_buff *skb_clone(struct sk_buff *skb,
A
Al Viro 已提交
568
				 gfp_t priority);
V
Victor Fusco 已提交
569
extern struct sk_buff *skb_copy(const struct sk_buff *skb,
A
Al Viro 已提交
570
				gfp_t priority);
E
Eric Dumazet 已提交
571 572 573
extern struct sk_buff *__pskb_copy(struct sk_buff *skb,
				 int headroom, gfp_t gfp_mask);

L
Linus Torvalds 已提交
574
extern int	       pskb_expand_head(struct sk_buff *skb,
V
Victor Fusco 已提交
575
					int nhead, int ntail,
A
Al Viro 已提交
576
					gfp_t gfp_mask);
L
Linus Torvalds 已提交
577 578 579 580
extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
					    unsigned int headroom);
extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
				       int newheadroom, int newtailroom,
A
Al Viro 已提交
581
				       gfp_t priority);
582 583 584 585 586
extern int	       skb_to_sgvec(struct sk_buff *skb,
				    struct scatterlist *sg, int offset,
				    int len);
extern int	       skb_cow_data(struct sk_buff *skb, int tailbits,
				    struct sk_buff **trailer);
587
extern int	       skb_pad(struct sk_buff *skb, int pad);
588
#define dev_kfree_skb(a)	consume_skb(a)
L
Linus Torvalds 已提交
589

590 591 592 593 594
extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
			int getfrag(void *from, char *to, int offset,
			int len,int odd, struct sk_buff *skb),
			void *from, int length);

E
Eric Dumazet 已提交
595
struct skb_seq_state {
596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611
	__u32		lower_offset;
	__u32		upper_offset;
	__u32		frag_idx;
	__u32		stepped_offset;
	struct sk_buff	*root_skb;
	struct sk_buff	*cur_skb;
	__u8		*frag_data;
};

extern void	      skb_prepare_seq_read(struct sk_buff *skb,
					   unsigned int from, unsigned int to,
					   struct skb_seq_state *st);
extern unsigned int   skb_seq_read(unsigned int consumed, const u8 **data,
				   struct skb_seq_state *st);
extern void	      skb_abort_seq_read(struct skb_seq_state *st);

612 613 614 615
extern unsigned int   skb_find_text(struct sk_buff *skb, unsigned int from,
				    unsigned int to, struct ts_config *config,
				    struct ts_state *state);

616
extern void __skb_get_rxhash(struct sk_buff *skb);
617 618 619
static inline __u32 skb_get_rxhash(struct sk_buff *skb)
{
	if (!skb->rxhash)
620
		__skb_get_rxhash(skb);
621 622 623 624

	return skb->rxhash;
}

625 626 627 628 629 630 631 632 633 634 635 636
#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
{
	return skb->head + skb->end;
}
#else
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
{
	return skb->end;
}
#endif

L
Linus Torvalds 已提交
637
/* Internal */
638
#define skb_shinfo(SKB)	((struct skb_shared_info *)(skb_end_pointer(SKB)))
L
Linus Torvalds 已提交
639

640 641 642 643 644
static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb)
{
	return &skb_shinfo(skb)->hwtstamps;
}

L
Linus Torvalds 已提交
645 646 647 648 649 650 651 652 653 654 655
/**
 *	skb_queue_empty - check if a queue is empty
 *	@list: queue head
 *
 *	Returns true if the queue is empty, false otherwise.
 */
static inline int skb_queue_empty(const struct sk_buff_head *list)
{
	return list->next == (struct sk_buff *)list;
}

D
David S. Miller 已提交
656 657 658 659 660 661 662 663 664 665
/**
 *	skb_queue_is_last - check if skb is the last entry in the queue
 *	@list: queue head
 *	@skb: buffer
 *
 *	Returns true if @skb is the last buffer on the list.
 */
static inline bool skb_queue_is_last(const struct sk_buff_head *list,
				     const struct sk_buff *skb)
{
E
Eric Dumazet 已提交
666
	return skb->next == (struct sk_buff *)list;
D
David S. Miller 已提交
667 668
}

669 670 671 672 673 674 675 676 677 678
/**
 *	skb_queue_is_first - check if skb is the first entry in the queue
 *	@list: queue head
 *	@skb: buffer
 *
 *	Returns true if @skb is the first buffer on the list.
 */
static inline bool skb_queue_is_first(const struct sk_buff_head *list,
				      const struct sk_buff *skb)
{
E
Eric Dumazet 已提交
679
	return skb->prev == (struct sk_buff *)list;
680 681
}

D
David S. Miller 已提交
682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699
/**
 *	skb_queue_next - return the next packet in the queue
 *	@list: queue head
 *	@skb: current buffer
 *
 *	Return the next packet in @list after @skb.  It is only valid to
 *	call this if skb_queue_is_last() evaluates to false.
 */
static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list,
					     const struct sk_buff *skb)
{
	/* This BUG_ON may seem severe, but if we just return then we
	 * are going to dereference garbage.
	 */
	BUG_ON(skb_queue_is_last(list, skb));
	return skb->next;
}

700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717
/**
 *	skb_queue_prev - return the prev packet in the queue
 *	@list: queue head
 *	@skb: current buffer
 *
 *	Return the prev packet in @list before @skb.  It is only valid to
 *	call this if skb_queue_is_first() evaluates to false.
 */
static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list,
					     const struct sk_buff *skb)
{
	/* This BUG_ON may seem severe, but if we just return then we
	 * are going to dereference garbage.
	 */
	BUG_ON(skb_queue_is_first(list, skb));
	return skb->prev;
}

L
Linus Torvalds 已提交
718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808
/**
 *	skb_get - reference buffer
 *	@skb: buffer to reference
 *
 *	Makes another reference to a socket buffer and returns a pointer
 *	to the buffer.
 */
static inline struct sk_buff *skb_get(struct sk_buff *skb)
{
	atomic_inc(&skb->users);
	return skb;
}

/*
 * If users == 1, we are the only owner and are can avoid redundant
 * atomic change.
 */

/**
 *	skb_cloned - is the buffer a clone
 *	@skb: buffer to check
 *
 *	Returns true if the buffer was generated with skb_clone() and is
 *	one of multiple shared copies of the buffer. Cloned buffers are
 *	shared data so must not be written to under normal circumstances.
 */
static inline int skb_cloned(const struct sk_buff *skb)
{
	return skb->cloned &&
	       (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
}

/**
 *	skb_header_cloned - is the header a clone
 *	@skb: buffer to check
 *
 *	Returns true if modifying the header part of the buffer requires
 *	the data to be copied.
 */
static inline int skb_header_cloned(const struct sk_buff *skb)
{
	int dataref;

	if (!skb->cloned)
		return 0;

	dataref = atomic_read(&skb_shinfo(skb)->dataref);
	dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
	return dataref != 1;
}

/**
 *	skb_header_release - release reference to header
 *	@skb: buffer to operate on
 *
 *	Drop a reference to the header part of the buffer.  This is done
 *	by acquiring a payload reference.  You must not read from the header
 *	part of skb->data after this.
 */
static inline void skb_header_release(struct sk_buff *skb)
{
	BUG_ON(skb->nohdr);
	skb->nohdr = 1;
	atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
}

/**
 *	skb_shared - is the buffer shared
 *	@skb: buffer to check
 *
 *	Returns true if more than one person has a reference to this
 *	buffer.
 */
static inline int skb_shared(const struct sk_buff *skb)
{
	return atomic_read(&skb->users) != 1;
}

/**
 *	skb_share_check - check if buffer is shared and if so clone it
 *	@skb: buffer to check
 *	@pri: priority for memory allocation
 *
 *	If the buffer is shared the buffer is cloned and the old copy
 *	drops a reference. A new clone with a single reference is returned.
 *	If the buffer is not shared the original buffer is returned. When
 *	being called from interrupt status or with spinlocks held pri must
 *	be GFP_ATOMIC.
 *
 *	NULL is returned on a memory allocation failure.
 */
V
Victor Fusco 已提交
809
static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
A
Al Viro 已提交
810
					      gfp_t pri)
L
Linus Torvalds 已提交
811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
{
	might_sleep_if(pri & __GFP_WAIT);
	if (skb_shared(skb)) {
		struct sk_buff *nskb = skb_clone(skb, pri);
		kfree_skb(skb);
		skb = nskb;
	}
	return skb;
}

/*
 *	Copy shared buffers into a new sk_buff. We effectively do COW on
 *	packets to handle cases where we have a local reader and forward
 *	and a couple of other messy ones. The normal one is tcpdumping
 *	a packet thats being forwarded.
 */

/**
 *	skb_unshare - make a copy of a shared buffer
 *	@skb: buffer to check
 *	@pri: priority for memory allocation
 *
 *	If the socket buffer is a clone then this function creates a new
 *	copy of the data, drops a reference count on the old copy and returns
 *	the new copy with the reference count at 1. If the buffer is not a clone
 *	the original buffer is returned. When called with a spinlock held or
 *	from interrupt state @pri must be %GFP_ATOMIC
 *
 *	%NULL is returned on a memory allocation failure.
 */
841
static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
A
Al Viro 已提交
842
					  gfp_t pri)
L
Linus Torvalds 已提交
843 844 845 846 847 848 849 850 851 852 853
{
	might_sleep_if(pri & __GFP_WAIT);
	if (skb_cloned(skb)) {
		struct sk_buff *nskb = skb_copy(skb, pri);
		kfree_skb(skb);	/* Free our shared copy */
		skb = nskb;
	}
	return skb;
}

/**
854
 *	skb_peek - peek at the head of an &sk_buff_head
L
Linus Torvalds 已提交
855 856 857 858 859 860 861 862 863 864 865
 *	@list_: list to peek at
 *
 *	Peek an &sk_buff. Unlike most other operations you _MUST_
 *	be careful with this one. A peek leaves the buffer on the
 *	list and someone else may run off with it. You must hold
 *	the appropriate locks or have a private queue to do this.
 *
 *	Returns %NULL for an empty list or a pointer to the head element.
 *	The reference count is not incremented and the reference is therefore
 *	volatile. Use with caution.
 */
866
static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_)
L
Linus Torvalds 已提交
867
{
868
	struct sk_buff *list = ((const struct sk_buff *)list_)->next;
L
Linus Torvalds 已提交
869 870 871 872 873 874
	if (list == (struct sk_buff *)list_)
		list = NULL;
	return list;
}

/**
875
 *	skb_peek_tail - peek at the tail of an &sk_buff_head
L
Linus Torvalds 已提交
876 877 878 879 880 881 882 883 884 885 886
 *	@list_: list to peek at
 *
 *	Peek an &sk_buff. Unlike most other operations you _MUST_
 *	be careful with this one. A peek leaves the buffer on the
 *	list and someone else may run off with it. You must hold
 *	the appropriate locks or have a private queue to do this.
 *
 *	Returns %NULL for an empty list or a pointer to the tail element.
 *	The reference count is not incremented and the reference is therefore
 *	volatile. Use with caution.
 */
887
static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_)
L
Linus Torvalds 已提交
888
{
889
	struct sk_buff *list = ((const struct sk_buff *)list_)->prev;
L
Linus Torvalds 已提交
890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905
	if (list == (struct sk_buff *)list_)
		list = NULL;
	return list;
}

/**
 *	skb_queue_len	- get queue length
 *	@list_: list to measure
 *
 *	Return the length of an &sk_buff queue.
 */
static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
{
	return list_->qlen;
}

906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921
/**
 *	__skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
 *	@list: queue to initialize
 *
 *	This initializes only the list and queue length aspects of
 *	an sk_buff_head object.  This allows to initialize the list
 *	aspects of an sk_buff_head without reinitializing things like
 *	the spinlock.  It can also be used for on-stack sk_buff_head
 *	objects where the spinlock is known to not be used.
 */
static inline void __skb_queue_head_init(struct sk_buff_head *list)
{
	list->prev = list->next = (struct sk_buff *)list;
	list->qlen = 0;
}

922 923 924 925 926 927 928 929
/*
 * This function creates a split out lock class for each invocation;
 * this is needed for now since a whole lot of users of the skb-queue
 * infrastructure in drivers have different locking usage (in hardirq)
 * than the networking core (in softirq only). In the long run either the
 * network layer or drivers should need annotation to consolidate the
 * main types of usage into 3 classes.
 */
L
Linus Torvalds 已提交
930 931 932
static inline void skb_queue_head_init(struct sk_buff_head *list)
{
	spin_lock_init(&list->lock);
933
	__skb_queue_head_init(list);
L
Linus Torvalds 已提交
934 935
}

936 937 938 939 940 941 942
static inline void skb_queue_head_init_class(struct sk_buff_head *list,
		struct lock_class_key *class)
{
	skb_queue_head_init(list);
	lockdep_set_class(&list->lock, class);
}

L
Linus Torvalds 已提交
943
/*
944
 *	Insert an sk_buff on a list.
L
Linus Torvalds 已提交
945 946 947 948
 *
 *	The "__skb_xxxx()" functions are the non-atomic ones that
 *	can only be called with interrupts disabled.
 */
949 950 951 952 953 954 955 956 957 958
extern void        skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
static inline void __skb_insert(struct sk_buff *newsk,
				struct sk_buff *prev, struct sk_buff *next,
				struct sk_buff_head *list)
{
	newsk->next = next;
	newsk->prev = prev;
	next->prev  = prev->next = newsk;
	list->qlen++;
}
L
Linus Torvalds 已提交
959

960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983
static inline void __skb_queue_splice(const struct sk_buff_head *list,
				      struct sk_buff *prev,
				      struct sk_buff *next)
{
	struct sk_buff *first = list->next;
	struct sk_buff *last = list->prev;

	first->prev = prev;
	prev->next = first;

	last->next = next;
	next->prev = last;
}

/**
 *	skb_queue_splice - join two skb lists, this is designed for stacks
 *	@list: the new list to add
 *	@head: the place to add it in the first list
 */
static inline void skb_queue_splice(const struct sk_buff_head *list,
				    struct sk_buff_head *head)
{
	if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, (struct sk_buff *) head, head->next);
984
		head->qlen += list->qlen;
985 986 987 988 989 990 991 992 993 994 995 996 997 998 999
	}
}

/**
 *	skb_queue_splice - join two skb lists and reinitialise the emptied list
 *	@list: the new list to add
 *	@head: the place to add it in the first list
 *
 *	The list at @list is reinitialised
 */
static inline void skb_queue_splice_init(struct sk_buff_head *list,
					 struct sk_buff_head *head)
{
	if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, (struct sk_buff *) head, head->next);
1000
		head->qlen += list->qlen;
1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014
		__skb_queue_head_init(list);
	}
}

/**
 *	skb_queue_splice_tail - join two skb lists, each list being a queue
 *	@list: the new list to add
 *	@head: the place to add it in the first list
 */
static inline void skb_queue_splice_tail(const struct sk_buff_head *list,
					 struct sk_buff_head *head)
{
	if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
1015
		head->qlen += list->qlen;
1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031
	}
}

/**
 *	skb_queue_splice_tail - join two skb lists and reinitialise the emptied list
 *	@list: the new list to add
 *	@head: the place to add it in the first list
 *
 *	Each of the lists is a queue.
 *	The list at @list is reinitialised
 */
static inline void skb_queue_splice_tail_init(struct sk_buff_head *list,
					      struct sk_buff_head *head)
{
	if (!skb_queue_empty(list)) {
		__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
1032
		head->qlen += list->qlen;
1033 1034 1035 1036
		__skb_queue_head_init(list);
	}
}

L
Linus Torvalds 已提交
1037
/**
1038
 *	__skb_queue_after - queue a buffer at the list head
L
Linus Torvalds 已提交
1039
 *	@list: list to use
1040
 *	@prev: place after this buffer
L
Linus Torvalds 已提交
1041 1042
 *	@newsk: buffer to queue
 *
1043
 *	Queue a buffer int the middle of a list. This function takes no locks
L
Linus Torvalds 已提交
1044 1045 1046 1047
 *	and you must therefore hold required locks before calling it.
 *
 *	A buffer cannot be placed on two lists at the same time.
 */
1048 1049 1050
static inline void __skb_queue_after(struct sk_buff_head *list,
				     struct sk_buff *prev,
				     struct sk_buff *newsk)
L
Linus Torvalds 已提交
1051
{
1052
	__skb_insert(newsk, prev, prev->next, list);
L
Linus Torvalds 已提交
1053 1054
}

1055 1056 1057
extern void skb_append(struct sk_buff *old, struct sk_buff *newsk,
		       struct sk_buff_head *list);

1058 1059 1060 1061 1062 1063 1064
static inline void __skb_queue_before(struct sk_buff_head *list,
				      struct sk_buff *next,
				      struct sk_buff *newsk)
{
	__skb_insert(newsk, next->prev, next, list);
}

1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081
/**
 *	__skb_queue_head - queue a buffer at the list head
 *	@list: list to use
 *	@newsk: buffer to queue
 *
 *	Queue a buffer at the start of a list. This function takes no locks
 *	and you must therefore hold required locks before calling it.
 *
 *	A buffer cannot be placed on two lists at the same time.
 */
extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
static inline void __skb_queue_head(struct sk_buff_head *list,
				    struct sk_buff *newsk)
{
	__skb_queue_after(list, (struct sk_buff *)list, newsk);
}

L
Linus Torvalds 已提交
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095
/**
 *	__skb_queue_tail - queue a buffer at the list tail
 *	@list: list to use
 *	@newsk: buffer to queue
 *
 *	Queue a buffer at the end of a list. This function takes no locks
 *	and you must therefore hold required locks before calling it.
 *
 *	A buffer cannot be placed on two lists at the same time.
 */
extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
static inline void __skb_queue_tail(struct sk_buff_head *list,
				   struct sk_buff *newsk)
{
1096
	__skb_queue_before(list, (struct sk_buff *)list, newsk);
L
Linus Torvalds 已提交
1097 1098 1099 1100 1101 1102
}

/*
 * remove sk_buff from list. _Must_ be called atomically, and with
 * the list known..
 */
D
David S. Miller 已提交
1103
extern void	   skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
L
Linus Torvalds 已提交
1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115
static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
{
	struct sk_buff *next, *prev;

	list->qlen--;
	next	   = skb->next;
	prev	   = skb->prev;
	skb->next  = skb->prev = NULL;
	next->prev = prev;
	prev->next = next;
}

1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131
/**
 *	__skb_dequeue - remove from the head of the queue
 *	@list: list to dequeue from
 *
 *	Remove the head of the list. This function does not take any locks
 *	so must be used with appropriate locks held only. The head item is
 *	returned or %NULL if the list is empty.
 */
extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
{
	struct sk_buff *skb = skb_peek(list);
	if (skb)
		__skb_unlink(skb, list);
	return skb;
}
L
Linus Torvalds 已提交
1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165

/**
 *	__skb_dequeue_tail - remove from the tail of the queue
 *	@list: list to dequeue from
 *
 *	Remove the tail of the list. This function does not take any locks
 *	so must be used with appropriate locks held only. The tail item is
 *	returned or %NULL if the list is empty.
 */
extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
{
	struct sk_buff *skb = skb_peek_tail(list);
	if (skb)
		__skb_unlink(skb, list);
	return skb;
}


static inline int skb_is_nonlinear(const struct sk_buff *skb)
{
	return skb->data_len;
}

static inline unsigned int skb_headlen(const struct sk_buff *skb)
{
	return skb->len - skb->data_len;
}

static inline int skb_pagelen(const struct sk_buff *skb)
{
	int i, len = 0;

	for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
E
Eric Dumazet 已提交
1166
		len += skb_frag_size(&skb_shinfo(skb)->frags[i]);
L
Linus Torvalds 已提交
1167 1168 1169
	return len + skb_headlen(skb);
}

1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184
/**
 * __skb_fill_page_desc - initialise a paged fragment in an skb
 * @skb: buffer containing fragment to be initialised
 * @i: paged fragment index to initialise
 * @page: the page to use for this fragment
 * @off: the offset to the data with @page
 * @size: the length of the data
 *
 * Initialises the @i'th fragment of @skb to point to &size bytes at
 * offset @off within @page.
 *
 * Does not take any additional reference on the fragment.
 */
static inline void __skb_fill_page_desc(struct sk_buff *skb, int i,
					struct page *page, int off, int size)
L
Linus Torvalds 已提交
1185 1186 1187
{
	skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

1188
	frag->page.p		  = page;
L
Linus Torvalds 已提交
1189
	frag->page_offset	  = off;
E
Eric Dumazet 已提交
1190
	skb_frag_size_set(frag, size);
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210
}

/**
 * skb_fill_page_desc - initialise a paged fragment in an skb
 * @skb: buffer containing fragment to be initialised
 * @i: paged fragment index to initialise
 * @page: the page to use for this fragment
 * @off: the offset to the data with @page
 * @size: the length of the data
 *
 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
 * @skb to point to &size bytes at offset @off within @page. In
 * addition updates @skb such that @i is the last fragment.
 *
 * Does not take any additional reference on the fragment.
 */
static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
				      struct page *page, int off, int size)
{
	__skb_fill_page_desc(skb, i, page, off, size);
L
Linus Torvalds 已提交
1211 1212 1213
	skb_shinfo(skb)->nr_frags = i + 1;
}

P
Peter Zijlstra 已提交
1214 1215 1216
extern void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page,
			    int off, int size);

L
Linus Torvalds 已提交
1217
#define SKB_PAGE_ASSERT(skb) 	BUG_ON(skb_shinfo(skb)->nr_frags)
1218
#define SKB_FRAG_ASSERT(skb) 	BUG_ON(skb_has_frag_list(skb))
L
Linus Torvalds 已提交
1219 1220
#define SKB_LINEAR_ASSERT(skb)  BUG_ON(skb_is_nonlinear(skb))

1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251
#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
{
	return skb->head + skb->tail;
}

static inline void skb_reset_tail_pointer(struct sk_buff *skb)
{
	skb->tail = skb->data - skb->head;
}

static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
{
	skb_reset_tail_pointer(skb);
	skb->tail += offset;
}
#else /* NET_SKBUFF_DATA_USES_OFFSET */
static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
{
	return skb->tail;
}

static inline void skb_reset_tail_pointer(struct sk_buff *skb)
{
	skb->tail = skb->data;
}

static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
{
	skb->tail = skb->data + offset;
}
1252

1253 1254
#endif /* NET_SKBUFF_DATA_USES_OFFSET */

L
Linus Torvalds 已提交
1255 1256 1257
/*
 *	Add data to an sk_buff
 */
1258
extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
L
Linus Torvalds 已提交
1259 1260
static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
{
1261
	unsigned char *tmp = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1262 1263 1264 1265 1266 1267
	SKB_LINEAR_ASSERT(skb);
	skb->tail += len;
	skb->len  += len;
	return tmp;
}

1268
extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len);
L
Linus Torvalds 已提交
1269 1270 1271 1272 1273 1274 1275
static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
{
	skb->data -= len;
	skb->len  += len;
	return skb->data;
}

1276
extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);
L
Linus Torvalds 已提交
1277 1278 1279 1280 1281 1282 1283
static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
{
	skb->len -= len;
	BUG_ON(skb->len < skb->data_len);
	return skb->data += len;
}

1284 1285 1286 1287 1288
static inline unsigned char *skb_pull_inline(struct sk_buff *skb, unsigned int len)
{
	return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
}

L
Linus Torvalds 已提交
1289 1290 1291 1292 1293
extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);

static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
{
	if (len > skb_headlen(skb) &&
G
Gerrit Renker 已提交
1294
	    !__pskb_pull_tail(skb, len - skb_headlen(skb)))
L
Linus Torvalds 已提交
1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310
		return NULL;
	skb->len -= len;
	return skb->data += len;
}

static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
{
	return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
}

static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
{
	if (likely(len <= skb_headlen(skb)))
		return 1;
	if (unlikely(len > skb->len))
		return 0;
G
Gerrit Renker 已提交
1311
	return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL;
L
Linus Torvalds 已提交
1312 1313 1314 1315 1316 1317 1318 1319
}

/**
 *	skb_headroom - bytes at buffer head
 *	@skb: buffer to check
 *
 *	Return the number of bytes of free space at the head of an &sk_buff.
 */
1320
static inline unsigned int skb_headroom(const struct sk_buff *skb)
L
Linus Torvalds 已提交
1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332
{
	return skb->data - skb->head;
}

/**
 *	skb_tailroom - bytes at buffer end
 *	@skb: buffer to check
 *
 *	Return the number of bytes of free space at the tail of an sk_buff
 */
static inline int skb_tailroom(const struct sk_buff *skb)
{
1333
	return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
L
Linus Torvalds 已提交
1334 1335 1336 1337 1338 1339 1340 1341 1342 1343
}

/**
 *	skb_reserve - adjust headroom
 *	@skb: buffer to alter
 *	@len: bytes to move
 *
 *	Increase the headroom of an empty &sk_buff by reducing the tail
 *	room. This is only allowed for an empty buffer.
 */
1344
static inline void skb_reserve(struct sk_buff *skb, int len)
L
Linus Torvalds 已提交
1345 1346 1347 1348 1349
{
	skb->data += len;
	skb->tail += len;
}

1350 1351 1352 1353 1354
static inline void skb_reset_mac_len(struct sk_buff *skb)
{
	skb->mac_len = skb->network_header - skb->mac_header;
}

1355
#ifdef NET_SKBUFF_DATA_USES_OFFSET
1356 1357
static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
{
1358
	return skb->head + skb->transport_header;
1359 1360
}

1361 1362
static inline void skb_reset_transport_header(struct sk_buff *skb)
{
1363
	skb->transport_header = skb->data - skb->head;
1364 1365
}

1366 1367 1368
static inline void skb_set_transport_header(struct sk_buff *skb,
					    const int offset)
{
1369 1370
	skb_reset_transport_header(skb);
	skb->transport_header += offset;
1371 1372
}

1373 1374
static inline unsigned char *skb_network_header(const struct sk_buff *skb)
{
1375
	return skb->head + skb->network_header;
1376 1377
}

1378 1379
static inline void skb_reset_network_header(struct sk_buff *skb)
{
1380
	skb->network_header = skb->data - skb->head;
1381 1382
}

1383 1384
static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
{
1385 1386
	skb_reset_network_header(skb);
	skb->network_header += offset;
1387 1388
}

1389
static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1390
{
1391
	return skb->head + skb->mac_header;
1392 1393
}

1394
static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1395
{
1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440
	return skb->mac_header != ~0U;
}

static inline void skb_reset_mac_header(struct sk_buff *skb)
{
	skb->mac_header = skb->data - skb->head;
}

static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
{
	skb_reset_mac_header(skb);
	skb->mac_header += offset;
}

#else /* NET_SKBUFF_DATA_USES_OFFSET */

static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
{
	return skb->transport_header;
}

static inline void skb_reset_transport_header(struct sk_buff *skb)
{
	skb->transport_header = skb->data;
}

static inline void skb_set_transport_header(struct sk_buff *skb,
					    const int offset)
{
	skb->transport_header = skb->data + offset;
}

static inline unsigned char *skb_network_header(const struct sk_buff *skb)
{
	return skb->network_header;
}

static inline void skb_reset_network_header(struct sk_buff *skb)
{
	skb->network_header = skb->data;
}

static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
{
	skb->network_header = skb->data + offset;
1441 1442
}

1443 1444
static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
{
1445
	return skb->mac_header;
1446 1447 1448 1449
}

static inline int skb_mac_header_was_set(const struct sk_buff *skb)
{
1450
	return skb->mac_header != NULL;
1451 1452
}

1453 1454
static inline void skb_reset_mac_header(struct sk_buff *skb)
{
1455
	skb->mac_header = skb->data;
1456 1457
}

1458 1459
static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
{
1460
	skb->mac_header = skb->data + offset;
1461
}
1462 1463
#endif /* NET_SKBUFF_DATA_USES_OFFSET */

1464 1465 1466 1467 1468
static inline int skb_checksum_start_offset(const struct sk_buff *skb)
{
	return skb->csum_start - skb_headroom(skb);
}

1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482
static inline int skb_transport_offset(const struct sk_buff *skb)
{
	return skb_transport_header(skb) - skb->data;
}

static inline u32 skb_network_header_len(const struct sk_buff *skb)
{
	return skb->transport_header - skb->network_header;
}

static inline int skb_network_offset(const struct sk_buff *skb)
{
	return skb_network_header(skb) - skb->data;
}
1483

1484 1485 1486 1487 1488
static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len)
{
	return pskb_may_pull(skb, skb_network_offset(skb) + len);
}

L
Linus Torvalds 已提交
1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499
/*
 * CPUs often take a performance hit when accessing unaligned memory
 * locations. The actual performance hit varies, it can be small if the
 * hardware handles it or large if we have to take an exception and fix it
 * in software.
 *
 * Since an ethernet header is 14 bytes network drivers often end up with
 * the IP header at an unaligned offset. The IP header can be aligned by
 * shifting the start of the packet by 2 bytes. Drivers should do this
 * with:
 *
1500
 * skb_reserve(skb, NET_IP_ALIGN);
L
Linus Torvalds 已提交
1501 1502 1503 1504
 *
 * The downside to this alignment of the IP header is that the DMA is now
 * unaligned. On some architectures the cost of an unaligned DMA is high
 * and this cost outweighs the gains made by aligning the IP header.
1505
 *
L
Linus Torvalds 已提交
1506 1507 1508 1509 1510 1511 1512
 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
 * to be overridden.
 */
#ifndef NET_IP_ALIGN
#define NET_IP_ALIGN	2
#endif

1513 1514 1515 1516
/*
 * The networking layer reserves some headroom in skb data (via
 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
 * the header has to grow. In the default case, if the header has to grow
1517
 * 32 bytes or less we avoid the reallocation.
1518 1519 1520 1521 1522 1523 1524
 *
 * Unfortunately this headroom changes the DMA alignment of the resulting
 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
 * on some architectures. An architecture can override this value,
 * perhaps setting it to a cacheline in size (since that will maintain
 * cacheline alignment of the DMA). It must be a power of 2.
 *
1525
 * Various parts of the networking layer expect at least 32 bytes of
1526
 * headroom, you should not reduce this.
1527 1528 1529 1530
 *
 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
 * to reduce average number of cache lines per packet.
 * get_rps_cpus() for example only access one 64 bytes aligned block :
1531
 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
1532 1533
 */
#ifndef NET_SKB_PAD
1534
#define NET_SKB_PAD	max(32, L1_CACHE_BYTES)
1535 1536
#endif

1537
extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
L
Linus Torvalds 已提交
1538 1539 1540

static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
{
1541
	if (unlikely(skb_is_nonlinear(skb))) {
1542 1543 1544
		WARN_ON(1);
		return;
	}
1545 1546
	skb->len = len;
	skb_set_tail_pointer(skb, len);
L
Linus Torvalds 已提交
1547 1548
}

1549
extern void skb_trim(struct sk_buff *skb, unsigned int len);
L
Linus Torvalds 已提交
1550 1551 1552

static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
{
1553 1554 1555 1556
	if (skb->data_len)
		return ___pskb_trim(skb, len);
	__skb_trim(skb, len);
	return 0;
L
Linus Torvalds 已提交
1557 1558 1559 1560 1561 1562 1563
}

static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
{
	return (len < skb->len) ? __pskb_trim(skb, len) : 0;
}

1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578
/**
 *	pskb_trim_unique - remove end from a paged unique (not cloned) buffer
 *	@skb: buffer to alter
 *	@len: new length
 *
 *	This is identical to pskb_trim except that the caller knows that
 *	the skb is not cloned so we should never get an error due to out-
 *	of-memory.
 */
static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
{
	int err = pskb_trim(skb, len);
	BUG_ON(err);
}

L
Linus Torvalds 已提交
1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611
/**
 *	skb_orphan - orphan a buffer
 *	@skb: buffer to orphan
 *
 *	If a buffer currently has an owner then we call the owner's
 *	destructor function and make the @skb unowned. The buffer continues
 *	to exist but is no longer charged to its former owner.
 */
static inline void skb_orphan(struct sk_buff *skb)
{
	if (skb->destructor)
		skb->destructor(skb);
	skb->destructor = NULL;
	skb->sk		= NULL;
}

/**
 *	__skb_queue_purge - empty a list
 *	@list: list to empty
 *
 *	Delete all buffers on an &sk_buff list. Each buffer is removed from
 *	the list and one reference dropped. This function does not take the
 *	list lock and the caller must hold the relevant locks to use it.
 */
extern void skb_queue_purge(struct sk_buff_head *list);
static inline void __skb_queue_purge(struct sk_buff_head *list)
{
	struct sk_buff *skb;
	while ((skb = __skb_dequeue(list)) != NULL)
		kfree_skb(skb);
}

/**
1612
 *	__dev_alloc_skb - allocate an skbuff for receiving
L
Linus Torvalds 已提交
1613 1614 1615 1616 1617 1618 1619 1620
 *	@length: length to allocate
 *	@gfp_mask: get_free_pages mask, passed to alloc_skb
 *
 *	Allocate a new &sk_buff and assign it a usage count of one. The
 *	buffer has unspecified headroom built in. Users should allocate
 *	the headroom they think they need without accounting for the
 *	built in space. The built in space is used for optimisations.
 *
1621
 *	%NULL is returned if there is no free memory.
L
Linus Torvalds 已提交
1622 1623
 */
static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
A
Al Viro 已提交
1624
					      gfp_t gfp_mask)
L
Linus Torvalds 已提交
1625
{
1626
	struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
L
Linus Torvalds 已提交
1627
	if (likely(skb))
1628
		skb_reserve(skb, NET_SKB_PAD);
L
Linus Torvalds 已提交
1629 1630 1631
	return skb;
}

1632
extern struct sk_buff *dev_alloc_skb(unsigned int length);
L
Linus Torvalds 已提交
1633

1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655
extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
		unsigned int length, gfp_t gfp_mask);

/**
 *	netdev_alloc_skb - allocate an skbuff for rx on a specific device
 *	@dev: network device to receive on
 *	@length: length to allocate
 *
 *	Allocate a new &sk_buff and assign it a usage count of one. The
 *	buffer has unspecified headroom built in. Users should allocate
 *	the headroom they think they need without accounting for the
 *	built in space. The built in space is used for optimisations.
 *
 *	%NULL is returned if there is no free memory. Although this function
 *	allocates memory it can be called from an interrupt.
 */
static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
		unsigned int length)
{
	return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
}

1656 1657
static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
		unsigned int length, gfp_t gfp)
1658
{
1659
	struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
1660 1661 1662 1663 1664 1665

	if (NET_IP_ALIGN && skb)
		skb_reserve(skb, NET_IP_ALIGN);
	return skb;
}

1666 1667 1668 1669 1670 1671
static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
		unsigned int length)
{
	return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC);
}

1672 1673 1674 1675 1676 1677 1678 1679
/**
 * skb_frag_page - retrieve the page refered to by a paged fragment
 * @frag: the paged fragment
 *
 * Returns the &struct page associated with @frag.
 */
static inline struct page *skb_frag_page(const skb_frag_t *frag)
{
1680
	return frag->page.p;
1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765
}

/**
 * __skb_frag_ref - take an addition reference on a paged fragment.
 * @frag: the paged fragment
 *
 * Takes an additional reference on the paged fragment @frag.
 */
static inline void __skb_frag_ref(skb_frag_t *frag)
{
	get_page(skb_frag_page(frag));
}

/**
 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
 * @skb: the buffer
 * @f: the fragment offset.
 *
 * Takes an additional reference on the @f'th paged fragment of @skb.
 */
static inline void skb_frag_ref(struct sk_buff *skb, int f)
{
	__skb_frag_ref(&skb_shinfo(skb)->frags[f]);
}

/**
 * __skb_frag_unref - release a reference on a paged fragment.
 * @frag: the paged fragment
 *
 * Releases a reference on the paged fragment @frag.
 */
static inline void __skb_frag_unref(skb_frag_t *frag)
{
	put_page(skb_frag_page(frag));
}

/**
 * skb_frag_unref - release a reference on a paged fragment of an skb.
 * @skb: the buffer
 * @f: the fragment offset
 *
 * Releases a reference on the @f'th paged fragment of @skb.
 */
static inline void skb_frag_unref(struct sk_buff *skb, int f)
{
	__skb_frag_unref(&skb_shinfo(skb)->frags[f]);
}

/**
 * skb_frag_address - gets the address of the data contained in a paged fragment
 * @frag: the paged fragment buffer
 *
 * Returns the address of the data within @frag. The page must already
 * be mapped.
 */
static inline void *skb_frag_address(const skb_frag_t *frag)
{
	return page_address(skb_frag_page(frag)) + frag->page_offset;
}

/**
 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
 * @frag: the paged fragment buffer
 *
 * Returns the address of the data within @frag. Checks that the page
 * is mapped and returns %NULL otherwise.
 */
static inline void *skb_frag_address_safe(const skb_frag_t *frag)
{
	void *ptr = page_address(skb_frag_page(frag));
	if (unlikely(!ptr))
		return NULL;

	return ptr + frag->page_offset;
}

/**
 * __skb_frag_set_page - sets the page contained in a paged fragment
 * @frag: the paged fragment
 * @page: the page to set
 *
 * Sets the fragment @frag to contain @page.
 */
static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page)
{
1766
	frag->page.p = page;
1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784
}

/**
 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
 * @skb: the buffer
 * @f: the fragment offset
 * @page: the page to set
 *
 * Sets the @f'th fragment of @skb to contain @page.
 */
static inline void skb_frag_set_page(struct sk_buff *skb, int f,
				     struct page *page)
{
	__skb_frag_set_page(&skb_shinfo(skb)->frags[f], page);
}

/**
 * skb_frag_dma_map - maps a paged fragment via the DMA API
1785
 * @dev: the device to map the fragment to
1786 1787 1788 1789
 * @frag: the paged fragment to map
 * @offset: the offset within the fragment (starting at the
 *          fragment's own offset)
 * @size: the number of bytes to map
1790
 * @dir: the direction of the mapping (%PCI_DMA_*)
1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802
 *
 * Maps the page associated with @frag to @device.
 */
static inline dma_addr_t skb_frag_dma_map(struct device *dev,
					  const skb_frag_t *frag,
					  size_t offset, size_t size,
					  enum dma_data_direction dir)
{
	return dma_map_page(dev, skb_frag_page(frag),
			    frag->page_offset + offset, size, dir);
}

E
Eric Dumazet 已提交
1803 1804 1805 1806 1807 1808
static inline struct sk_buff *pskb_copy(struct sk_buff *skb,
					gfp_t gfp_mask)
{
	return __pskb_copy(skb, skb_headroom(skb), gfp_mask);
}

1809 1810 1811 1812 1813 1814 1815 1816
/**
 *	skb_clone_writable - is the header of a clone writable
 *	@skb: buffer to check
 *	@len: length up to which to write
 *
 *	Returns true if modifying the header part of the cloned buffer
 *	does not requires the data to be copied.
 */
1817
static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len)
1818 1819 1820 1821 1822
{
	return !skb_header_cloned(skb) &&
	       skb_headroom(skb) + len <= skb->hdr_len;
}

H
Herbert Xu 已提交
1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838
static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
			    int cloned)
{
	int delta = 0;

	if (headroom < NET_SKB_PAD)
		headroom = NET_SKB_PAD;
	if (headroom > skb_headroom(skb))
		delta = headroom - skb_headroom(skb);

	if (delta || cloned)
		return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
					GFP_ATOMIC);
	return 0;
}

L
Linus Torvalds 已提交
1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852
/**
 *	skb_cow - copy header of skb when it is required
 *	@skb: buffer to cow
 *	@headroom: needed headroom
 *
 *	If the skb passed lacks sufficient headroom or its data part
 *	is shared, data is reallocated. If reallocation fails, an error
 *	is returned and original skb is not changed.
 *
 *	The result is skb with writable area skb->head...skb->tail
 *	and at least @headroom of space at head.
 */
static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
{
H
Herbert Xu 已提交
1853 1854
	return __skb_cow(skb, headroom, skb_cloned(skb));
}
L
Linus Torvalds 已提交
1855

H
Herbert Xu 已提交
1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868
/**
 *	skb_cow_head - skb_cow but only making the head writable
 *	@skb: buffer to cow
 *	@headroom: needed headroom
 *
 *	This function is identical to skb_cow except that we replace the
 *	skb_cloned check by skb_header_cloned.  It should be used when
 *	you only need to push on some header and do not need to modify
 *	the data.
 */
static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
{
	return __skb_cow(skb, headroom, skb_header_cloned(skb));
L
Linus Torvalds 已提交
1869 1870 1871 1872 1873 1874 1875 1876 1877
}

/**
 *	skb_padto	- pad an skbuff up to a minimal size
 *	@skb: buffer to pad
 *	@len: minimal length
 *
 *	Pads up a buffer to ensure the trailing bytes exist and are
 *	blanked. If the buffer already contains sufficient data it
1878 1879
 *	is untouched. Otherwise it is extended. Returns zero on
 *	success. The skb is freed on error.
L
Linus Torvalds 已提交
1880 1881
 */
 
1882
static inline int skb_padto(struct sk_buff *skb, unsigned int len)
L
Linus Torvalds 已提交
1883 1884 1885
{
	unsigned int size = skb->len;
	if (likely(size >= len))
1886
		return 0;
G
Gerrit Renker 已提交
1887
	return skb_pad(skb, len - size);
L
Linus Torvalds 已提交
1888 1889 1890 1891 1892 1893 1894 1895 1896
}

static inline int skb_add_data(struct sk_buff *skb,
			       char __user *from, int copy)
{
	const int off = skb->len;

	if (skb->ip_summed == CHECKSUM_NONE) {
		int err = 0;
1897
		__wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
L
Linus Torvalds 已提交
1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910
							    copy, 0, &err);
		if (!err) {
			skb->csum = csum_block_add(skb->csum, csum, off);
			return 0;
		}
	} else if (!copy_from_user(skb_put(skb, copy), from, copy))
		return 0;

	__skb_trim(skb, off);
	return -EFAULT;
}

static inline int skb_can_coalesce(struct sk_buff *skb, int i,
1911
				   const struct page *page, int off)
L
Linus Torvalds 已提交
1912 1913
{
	if (i) {
E
Eric Dumazet 已提交
1914
		const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
L
Linus Torvalds 已提交
1915

1916
		return page == skb_frag_page(frag) &&
E
Eric Dumazet 已提交
1917
		       off == frag->page_offset + skb_frag_size(frag);
L
Linus Torvalds 已提交
1918 1919 1920 1921
	}
	return 0;
}

H
Herbert Xu 已提交
1922 1923 1924 1925 1926
static inline int __skb_linearize(struct sk_buff *skb)
{
	return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
}

L
Linus Torvalds 已提交
1927 1928 1929 1930 1931 1932 1933
/**
 *	skb_linearize - convert paged skb to linear one
 *	@skb: buffer to linarize
 *
 *	If there is no free memory -ENOMEM is returned, otherwise zero
 *	is returned and the old skb data released.
 */
H
Herbert Xu 已提交
1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946
static inline int skb_linearize(struct sk_buff *skb)
{
	return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
}

/**
 *	skb_linearize_cow - make sure skb is linear and writable
 *	@skb: buffer to process
 *
 *	If there is no free memory -ENOMEM is returned, otherwise zero
 *	is returned and the old skb data released.
 */
static inline int skb_linearize_cow(struct sk_buff *skb)
L
Linus Torvalds 已提交
1947
{
H
Herbert Xu 已提交
1948 1949
	return skb_is_nonlinear(skb) || skb_cloned(skb) ?
	       __skb_linearize(skb) : 0;
L
Linus Torvalds 已提交
1950 1951 1952 1953 1954 1955 1956 1957 1958
}

/**
 *	skb_postpull_rcsum - update checksum for received skb after pull
 *	@skb: buffer to update
 *	@start: start of data before pull
 *	@len: length of data pulled
 *
 *	After doing a pull on a received packet, you need to call this to
1959 1960
 *	update the CHECKSUM_COMPLETE checksum, or set ip_summed to
 *	CHECKSUM_NONE so that it can be recomputed from scratch.
L
Linus Torvalds 已提交
1961 1962 1963
 */

static inline void skb_postpull_rcsum(struct sk_buff *skb,
1964
				      const void *start, unsigned int len)
L
Linus Torvalds 已提交
1965
{
1966
	if (skb->ip_summed == CHECKSUM_COMPLETE)
L
Linus Torvalds 已提交
1967 1968 1969
		skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
}

1970 1971
unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);

L
Linus Torvalds 已提交
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982
/**
 *	pskb_trim_rcsum - trim received skb and update checksum
 *	@skb: buffer to trim
 *	@len: new length
 *
 *	This is exactly the same as pskb_trim except that it ensures the
 *	checksum of received packets are still valid after the operation.
 */

static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
{
1983
	if (likely(len >= skb->len))
L
Linus Torvalds 已提交
1984
		return 0;
1985
	if (skb->ip_summed == CHECKSUM_COMPLETE)
L
Linus Torvalds 已提交
1986 1987 1988 1989 1990 1991
		skb->ip_summed = CHECKSUM_NONE;
	return __pskb_trim(skb, len);
}

#define skb_queue_walk(queue, skb) \
		for (skb = (queue)->next;					\
1992
		     skb != (struct sk_buff *)(queue);				\
L
Linus Torvalds 已提交
1993 1994
		     skb = skb->next)

1995 1996 1997 1998 1999
#define skb_queue_walk_safe(queue, skb, tmp)					\
		for (skb = (queue)->next, tmp = skb->next;			\
		     skb != (struct sk_buff *)(queue);				\
		     skb = tmp, tmp = skb->next)

2000
#define skb_queue_walk_from(queue, skb)						\
2001
		for (; skb != (struct sk_buff *)(queue);			\
2002 2003 2004 2005 2006 2007 2008
		     skb = skb->next)

#define skb_queue_walk_from_safe(queue, skb, tmp)				\
		for (tmp = skb->next;						\
		     skb != (struct sk_buff *)(queue);				\
		     skb = tmp, tmp = skb->next)

2009 2010
#define skb_queue_reverse_walk(queue, skb) \
		for (skb = (queue)->prev;					\
2011
		     skb != (struct sk_buff *)(queue);				\
2012 2013
		     skb = skb->prev)

2014 2015 2016 2017 2018 2019 2020 2021 2022
#define skb_queue_reverse_walk_safe(queue, skb, tmp)				\
		for (skb = (queue)->prev, tmp = skb->prev;			\
		     skb != (struct sk_buff *)(queue);				\
		     skb = tmp, tmp = skb->prev)

#define skb_queue_reverse_walk_from_safe(queue, skb, tmp)			\
		for (tmp = skb->prev;						\
		     skb != (struct sk_buff *)(queue);				\
		     skb = tmp, tmp = skb->prev)
L
Linus Torvalds 已提交
2023

2024
static inline bool skb_has_frag_list(const struct sk_buff *skb)
2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042
{
	return skb_shinfo(skb)->frag_list != NULL;
}

static inline void skb_frag_list_init(struct sk_buff *skb)
{
	skb_shinfo(skb)->frag_list = NULL;
}

static inline void skb_frag_add_head(struct sk_buff *skb, struct sk_buff *frag)
{
	frag->next = skb_shinfo(skb)->frag_list;
	skb_shinfo(skb)->frag_list = frag;
}

#define skb_walk_frags(skb, iter)	\
	for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)

2043 2044
extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
					   int *peeked, int *err);
L
Linus Torvalds 已提交
2045 2046 2047 2048 2049 2050 2051
extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
					 int noblock, int *err);
extern unsigned int    datagram_poll(struct file *file, struct socket *sock,
				     struct poll_table_struct *wait);
extern int	       skb_copy_datagram_iovec(const struct sk_buff *from,
					       int offset, struct iovec *to,
					       int size);
2052
extern int	       skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
L
Linus Torvalds 已提交
2053 2054
							int hlen,
							struct iovec *iov);
2055 2056
extern int	       skb_copy_datagram_from_iovec(struct sk_buff *skb,
						    int offset,
2057 2058
						    const struct iovec *from,
						    int from_offset,
2059
						    int len);
2060 2061 2062 2063 2064
extern int	       skb_copy_datagram_const_iovec(const struct sk_buff *from,
						     int offset,
						     const struct iovec *to,
						     int to_offset,
						     int size);
L
Linus Torvalds 已提交
2065
extern void	       skb_free_datagram(struct sock *sk, struct sk_buff *skb);
2066 2067
extern void	       skb_free_datagram_locked(struct sock *sk,
						struct sk_buff *skb);
2068
extern int	       skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
2069
					 unsigned int flags);
2070 2071
extern __wsum	       skb_checksum(const struct sk_buff *skb, int offset,
				    int len, __wsum csum);
L
Linus Torvalds 已提交
2072 2073
extern int	       skb_copy_bits(const struct sk_buff *skb, int offset,
				     void *to, int len);
2074 2075
extern int	       skb_store_bits(struct sk_buff *skb, int offset,
				      const void *from, int len);
2076
extern __wsum	       skb_copy_and_csum_bits(const struct sk_buff *skb,
L
Linus Torvalds 已提交
2077
					      int offset, u8 *to, int len,
2078
					      __wsum csum);
J
Jens Axboe 已提交
2079 2080 2081 2082 2083
extern int             skb_splice_bits(struct sk_buff *skb,
						unsigned int offset,
						struct pipe_inode_info *pipe,
						unsigned int len,
						unsigned int flags);
L
Linus Torvalds 已提交
2084 2085 2086
extern void	       skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
extern void	       skb_split(struct sk_buff *skb,
				 struct sk_buff *skb1, const u32 len);
2087 2088
extern int	       skb_shift(struct sk_buff *tgt, struct sk_buff *skb,
				 int shiftlen);
L
Linus Torvalds 已提交
2089

2090 2091
extern struct sk_buff *skb_segment(struct sk_buff *skb,
				   netdev_features_t features);
2092

L
Linus Torvalds 已提交
2093 2094 2095 2096 2097
static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
				       int len, void *buffer)
{
	int hlen = skb_headlen(skb);

2098
	if (hlen - offset >= len)
L
Linus Torvalds 已提交
2099 2100 2101 2102 2103 2104 2105 2106
		return skb->data + offset;

	if (skb_copy_bits(skb, offset, buffer, len) < 0)
		return NULL;

	return buffer;
}

2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120
static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
					     void *to,
					     const unsigned int len)
{
	memcpy(to, skb->data, len);
}

static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
						    const int offset, void *to,
						    const unsigned int len)
{
	memcpy(to, skb->data + offset, len);
}

2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135
static inline void skb_copy_to_linear_data(struct sk_buff *skb,
					   const void *from,
					   const unsigned int len)
{
	memcpy(skb->data, from, len);
}

static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
						  const int offset,
						  const void *from,
						  const unsigned int len)
{
	memcpy(skb->data + offset, from, len);
}

L
Linus Torvalds 已提交
2136 2137
extern void skb_init(void);

2138 2139 2140 2141 2142
static inline ktime_t skb_get_ktime(const struct sk_buff *skb)
{
	return skb->tstamp;
}

2143 2144 2145 2146 2147 2148 2149 2150 2151
/**
 *	skb_get_timestamp - get timestamp from a skb
 *	@skb: skb to get stamp from
 *	@stamp: pointer to struct timeval to store stamp in
 *
 *	Timestamps are stored in the skb as offsets to a base timestamp.
 *	This function converts the offset back to a struct timeval and stores
 *	it in stamp.
 */
2152 2153
static inline void skb_get_timestamp(const struct sk_buff *skb,
				     struct timeval *stamp)
2154
{
2155
	*stamp = ktime_to_timeval(skb->tstamp);
2156 2157
}

2158 2159 2160 2161 2162 2163
static inline void skb_get_timestampns(const struct sk_buff *skb,
				       struct timespec *stamp)
{
	*stamp = ktime_to_timespec(skb->tstamp);
}

2164
static inline void __net_timestamp(struct sk_buff *skb)
2165
{
2166
	skb->tstamp = ktime_get_real();
2167 2168
}

2169 2170 2171 2172 2173
static inline ktime_t net_timedelta(ktime_t t)
{
	return ktime_sub(ktime_get_real(), t);
}

2174 2175 2176 2177
static inline ktime_t net_invalid_timestamp(void)
{
	return ktime_set(0, 0);
}
2178

2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201
extern void skb_timestamping_init(void);

#ifdef CONFIG_NETWORK_PHY_TIMESTAMPING

extern void skb_clone_tx_timestamp(struct sk_buff *skb);
extern bool skb_defer_rx_timestamp(struct sk_buff *skb);

#else /* CONFIG_NETWORK_PHY_TIMESTAMPING */

static inline void skb_clone_tx_timestamp(struct sk_buff *skb)
{
}

static inline bool skb_defer_rx_timestamp(struct sk_buff *skb)
{
	return false;
}

#endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */

/**
 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
 *
2202 2203 2204 2205 2206
 * PHY drivers may accept clones of transmitted packets for
 * timestamping via their phy_driver.txtstamp method. These drivers
 * must call this function to return the skb back to the stack, with
 * or without a timestamp.
 *
2207
 * @skb: clone of the the original outgoing packet
2208
 * @hwtstamps: hardware time stamps, may be NULL if not available
2209 2210 2211 2212 2213
 *
 */
void skb_complete_tx_timestamp(struct sk_buff *skb,
			       struct skb_shared_hwtstamps *hwtstamps);

2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227
/**
 * skb_tstamp_tx - queue clone of skb with send time stamps
 * @orig_skb:	the original outgoing packet
 * @hwtstamps:	hardware time stamps, may be NULL if not available
 *
 * If the skb has a socket associated, then this function clones the
 * skb (thus sharing the actual data and optional structures), stores
 * the optional hardware time stamping information (if non NULL) or
 * generates a software time stamp (otherwise), then queues the clone
 * to the error queue of the socket.  Errors are silently ignored.
 */
extern void skb_tstamp_tx(struct sk_buff *orig_skb,
			struct skb_shared_hwtstamps *hwtstamps);

2228 2229
static inline void sw_tx_timestamp(struct sk_buff *skb)
{
2230 2231
	if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP &&
	    !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
2232 2233 2234 2235 2236 2237 2238
		skb_tstamp_tx(skb, NULL);
}

/**
 * skb_tx_timestamp() - Driver hook for transmit timestamping
 *
 * Ethernet MAC Drivers should call this function in their hard_xmit()
2239
 * function immediately before giving the sk_buff to the MAC hardware.
2240 2241 2242 2243 2244
 *
 * @skb: A socket buffer.
 */
static inline void skb_tx_timestamp(struct sk_buff *skb)
{
2245
	skb_clone_tx_timestamp(skb);
2246 2247 2248
	sw_tx_timestamp(skb);
}

2249 2250 2251 2252 2253 2254 2255 2256 2257
/**
 * skb_complete_wifi_ack - deliver skb with wifi status
 *
 * @skb: the original outgoing packet
 * @acked: ack status
 *
 */
void skb_complete_wifi_ack(struct sk_buff *skb, bool acked);

2258
extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
2259
extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
2260

2261 2262 2263 2264 2265
static inline int skb_csum_unnecessary(const struct sk_buff *skb)
{
	return skb->ip_summed & CHECKSUM_UNNECESSARY;
}

2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281
/**
 *	skb_checksum_complete - Calculate checksum of an entire packet
 *	@skb: packet to process
 *
 *	This function calculates the checksum over the entire packet plus
 *	the value of skb->csum.  The latter can be used to supply the
 *	checksum of a pseudo header as used by TCP/UDP.  It returns the
 *	checksum.
 *
 *	For protocols that contain complete checksums such as ICMP/TCP/UDP,
 *	this function can be used to verify that checksum on received
 *	packets.  In that case the function should return zero if the
 *	checksum is correct.  In particular, this function will return zero
 *	if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
 *	hardware has already verified the correctness of the checksum.
 */
2282
static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
2283
{
2284 2285
	return skb_csum_unnecessary(skb) ?
	       0 : __skb_checksum_complete(skb);
2286 2287
}

2288
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2289
extern void nf_conntrack_destroy(struct nf_conntrack *nfct);
L
Linus Torvalds 已提交
2290 2291 2292
static inline void nf_conntrack_put(struct nf_conntrack *nfct)
{
	if (nfct && atomic_dec_and_test(&nfct->use))
2293
		nf_conntrack_destroy(nfct);
L
Linus Torvalds 已提交
2294 2295 2296 2297 2298 2299
}
static inline void nf_conntrack_get(struct nf_conntrack *nfct)
{
	if (nfct)
		atomic_inc(&nfct->use);
}
2300 2301
#endif
#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312
static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
{
	if (skb)
		atomic_inc(&skb->users);
}
static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
{
	if (skb)
		kfree_skb(skb);
}
#endif
L
Linus Torvalds 已提交
2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
#ifdef CONFIG_BRIDGE_NETFILTER
static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
{
	if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
		kfree(nf_bridge);
}
static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
{
	if (nf_bridge)
		atomic_inc(&nf_bridge->use);
}
#endif /* CONFIG_BRIDGE_NETFILTER */
2325 2326
static inline void nf_reset(struct sk_buff *skb)
{
2327
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2328 2329
	nf_conntrack_put(skb->nfct);
	skb->nfct = NULL;
2330 2331
#endif
#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2332 2333 2334 2335 2336 2337 2338 2339 2340
	nf_conntrack_put_reasm(skb->nfct_reasm);
	skb->nfct_reasm = NULL;
#endif
#ifdef CONFIG_BRIDGE_NETFILTER
	nf_bridge_put(skb->nf_bridge);
	skb->nf_bridge = NULL;
#endif
}

2341 2342 2343
/* Note: This doesn't put any conntrack and bridge info in dst. */
static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
{
2344
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2345 2346 2347
	dst->nfct = src->nfct;
	nf_conntrack_get(src->nfct);
	dst->nfctinfo = src->nfctinfo;
2348 2349
#endif
#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2350 2351 2352 2353 2354 2355 2356 2357 2358
	dst->nfct_reasm = src->nfct_reasm;
	nf_conntrack_get_reasm(src->nfct_reasm);
#endif
#ifdef CONFIG_BRIDGE_NETFILTER
	dst->nf_bridge  = src->nf_bridge;
	nf_bridge_get(src->nf_bridge);
#endif
}

2359 2360 2361
static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
{
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2362
	nf_conntrack_put(dst->nfct);
2363 2364
#endif
#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2365 2366 2367 2368 2369 2370 2371 2372
	nf_conntrack_put_reasm(dst->nfct_reasm);
#endif
#ifdef CONFIG_BRIDGE_NETFILTER
	nf_bridge_put(dst->nf_bridge);
#endif
	__nf_copy(dst, src);
}

2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390
#ifdef CONFIG_NETWORK_SECMARK
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
{
	to->secmark = from->secmark;
}

static inline void skb_init_secmark(struct sk_buff *skb)
{
	skb->secmark = 0;
}
#else
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
{ }

static inline void skb_init_secmark(struct sk_buff *skb)
{ }
#endif

2391 2392 2393 2394 2395
static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
{
	skb->queue_mapping = queue_mapping;
}

2396
static inline u16 skb_get_queue_mapping(const struct sk_buff *skb)
2397 2398 2399 2400
{
	return skb->queue_mapping;
}

2401 2402 2403 2404 2405
static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
{
	to->queue_mapping = from->queue_mapping;
}

2406 2407 2408 2409 2410
static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue)
{
	skb->queue_mapping = rx_queue + 1;
}

2411
static inline u16 skb_get_rx_queue(const struct sk_buff *skb)
2412 2413 2414 2415
{
	return skb->queue_mapping - 1;
}

2416
static inline bool skb_rx_queue_recorded(const struct sk_buff *skb)
2417
{
E
Eric Dumazet 已提交
2418
	return skb->queue_mapping != 0;
2419 2420
}

2421 2422 2423
extern u16 __skb_tx_hash(const struct net_device *dev,
			 const struct sk_buff *skb,
			 unsigned int num_tx_queues);
2424

2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436
#ifdef CONFIG_XFRM
static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
{
	return skb->sp;
}
#else
static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
{
	return NULL;
}
#endif

H
Herbert Xu 已提交
2437 2438 2439 2440 2441
static inline int skb_is_gso(const struct sk_buff *skb)
{
	return skb_shinfo(skb)->gso_size;
}

B
Brice Goglin 已提交
2442 2443 2444 2445 2446
static inline int skb_is_gso_v6(const struct sk_buff *skb)
{
	return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
}

2447 2448 2449 2450 2451 2452
extern void __skb_warn_lro_forwarding(const struct sk_buff *skb);

static inline bool skb_warn_if_lro(const struct sk_buff *skb)
{
	/* LRO sets gso_size but not gso_type, whereas if GSO is really
	 * wanted then gso_type will be set. */
2453 2454
	const struct skb_shared_info *shinfo = skb_shinfo(skb);

2455 2456
	if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 &&
	    unlikely(shinfo->gso_type == 0)) {
2457 2458 2459 2460 2461 2462
		__skb_warn_lro_forwarding(skb);
		return true;
	}
	return false;
}

2463 2464 2465 2466 2467 2468 2469
static inline void skb_forward_csum(struct sk_buff *skb)
{
	/* Unfortunately we don't support this one.  Any brave souls? */
	if (skb->ip_summed == CHECKSUM_COMPLETE)
		skb->ip_summed = CHECKSUM_NONE;
}

2470 2471 2472 2473 2474 2475 2476 2477
/**
 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
 * @skb: skb to check
 *
 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
 * use this helper, to document places where we make this assertion.
 */
2478
static inline void skb_checksum_none_assert(const struct sk_buff *skb)
2479 2480 2481 2482 2483 2484
{
#ifdef DEBUG
	BUG_ON(skb->ip_summed != CHECKSUM_NONE);
#endif
}

2485
bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
2486

2487
static inline bool skb_is_recycleable(const struct sk_buff *skb, int skb_size)
2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506
{
	if (irqs_disabled())
		return false;

	if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY)
		return false;

	if (skb_is_nonlinear(skb) || skb->fclone != SKB_FCLONE_UNAVAILABLE)
		return false;

	skb_size = SKB_DATA_ALIGN(skb_size + NET_SKB_PAD);
	if (skb_end_pointer(skb) - skb->head < skb_size)
		return false;

	if (skb_shared(skb) || skb_cloned(skb))
		return false;

	return true;
}
L
Linus Torvalds 已提交
2507 2508
#endif	/* __KERNEL__ */
#endif	/* _LINUX_SKBUFF_H */