[SK_BUFF]: Use the helpers to get the layer header pointer
[linux-2.6/mini2440.git] / include / linux / skbuff.h
blob47c57be97d435493a16825c490d71ecc64c4951a
1 /*
2 * Definitions for the 'struct sk_buff' memory handlers.
4 * Authors:
5 * Alan Cox, <gw4pts@gw4pts.ampr.org>
6 * Florian La Roche, <rzsfl@rz.uni-sb.de>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
14 #ifndef _LINUX_SKBUFF_H
15 #define _LINUX_SKBUFF_H
17 #include <linux/kernel.h>
18 #include <linux/compiler.h>
19 #include <linux/time.h>
20 #include <linux/cache.h>
22 #include <asm/atomic.h>
23 #include <asm/types.h>
24 #include <linux/spinlock.h>
25 #include <linux/net.h>
26 #include <linux/textsearch.h>
27 #include <net/checksum.h>
28 #include <linux/rcupdate.h>
29 #include <linux/dmaengine.h>
30 #include <linux/hrtimer.h>
32 #define HAVE_ALLOC_SKB /* For the drivers to know */
33 #define HAVE_ALIGNABLE_SKB /* Ditto 8) */
35 #define CHECKSUM_NONE 0
36 #define CHECKSUM_PARTIAL 1
37 #define CHECKSUM_UNNECESSARY 2
38 #define CHECKSUM_COMPLETE 3
40 #define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \
41 ~(SMP_CACHE_BYTES - 1))
42 #define SKB_WITH_OVERHEAD(X) \
43 (((X) - sizeof(struct skb_shared_info)) & \
44 ~(SMP_CACHE_BYTES - 1))
45 #define SKB_MAX_ORDER(X, ORDER) \
46 SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
47 #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
48 #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
50 /* A. Checksumming of received packets by device.
52 * NONE: device failed to checksum this packet.
53 * skb->csum is undefined.
55 * UNNECESSARY: device parsed packet and wouldbe verified checksum.
56 * skb->csum is undefined.
57 * It is bad option, but, unfortunately, many of vendors do this.
58 * Apparently with secret goal to sell you new device, when you
59 * will add new protocol to your host. F.e. IPv6. 8)
61 * COMPLETE: the most generic way. Device supplied checksum of _all_
62 * the packet as seen by netif_rx in skb->csum.
63 * NOTE: Even if device supports only some protocols, but
64 * is able to produce some skb->csum, it MUST use COMPLETE,
65 * not UNNECESSARY.
67 * B. Checksumming on output.
69 * NONE: skb is checksummed by protocol or csum is not required.
71 * PARTIAL: device is required to csum packet as seen by hard_start_xmit
72 * from skb->h.raw to the end and to record the checksum
73 * at skb->h.raw+skb->csum.
75 * Device must show its capabilities in dev->features, set
76 * at device setup time.
77 * NETIF_F_HW_CSUM - it is clever device, it is able to checksum
78 * everything.
79 * NETIF_F_NO_CSUM - loopback or reliable single hop media.
80 * NETIF_F_IP_CSUM - device is dumb. It is able to csum only
81 * TCP/UDP over IPv4. Sigh. Vendors like this
82 * way by an unknown reason. Though, see comment above
83 * about CHECKSUM_UNNECESSARY. 8)
85 * Any questions? No questions, good. --ANK
88 struct net_device;
90 #ifdef CONFIG_NETFILTER
91 struct nf_conntrack {
92 atomic_t use;
93 void (*destroy)(struct nf_conntrack *);
96 #ifdef CONFIG_BRIDGE_NETFILTER
97 struct nf_bridge_info {
98 atomic_t use;
99 struct net_device *physindev;
100 struct net_device *physoutdev;
101 #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
102 struct net_device *netoutdev;
103 #endif
104 unsigned int mask;
105 unsigned long data[32 / sizeof(unsigned long)];
107 #endif
109 #endif
111 struct sk_buff_head {
112 /* These two members must be first. */
113 struct sk_buff *next;
114 struct sk_buff *prev;
116 __u32 qlen;
117 spinlock_t lock;
120 struct sk_buff;
122 /* To allow 64K frame to be packed as single skb without frag_list */
123 #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2)
125 typedef struct skb_frag_struct skb_frag_t;
127 struct skb_frag_struct {
128 struct page *page;
129 __u16 page_offset;
130 __u16 size;
133 /* This data is invariant across clones and lives at
134 * the end of the header data, ie. at skb->end.
136 struct skb_shared_info {
137 atomic_t dataref;
138 unsigned short nr_frags;
139 unsigned short gso_size;
140 /* Warning: this field is not always filled in (UFO)! */
141 unsigned short gso_segs;
142 unsigned short gso_type;
143 __be32 ip6_frag_id;
144 struct sk_buff *frag_list;
145 skb_frag_t frags[MAX_SKB_FRAGS];
148 /* We divide dataref into two halves. The higher 16 bits hold references
149 * to the payload part of skb->data. The lower 16 bits hold references to
150 * the entire skb->data. It is up to the users of the skb to agree on
151 * where the payload starts.
153 * All users must obey the rule that the skb->data reference count must be
154 * greater than or equal to the payload reference count.
156 * Holding a reference to the payload part means that the user does not
157 * care about modifications to the header part of skb->data.
159 #define SKB_DATAREF_SHIFT 16
160 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
163 enum {
164 SKB_FCLONE_UNAVAILABLE,
165 SKB_FCLONE_ORIG,
166 SKB_FCLONE_CLONE,
169 enum {
170 SKB_GSO_TCPV4 = 1 << 0,
171 SKB_GSO_UDP = 1 << 1,
173 /* This indicates the skb is from an untrusted source. */
174 SKB_GSO_DODGY = 1 << 2,
176 /* This indicates the tcp segment has CWR set. */
177 SKB_GSO_TCP_ECN = 1 << 3,
179 SKB_GSO_TCPV6 = 1 << 4,
182 /**
183 * struct sk_buff - socket buffer
184 * @next: Next buffer in list
185 * @prev: Previous buffer in list
186 * @sk: Socket we are owned by
187 * @tstamp: Time we arrived
188 * @dev: Device we arrived on/are leaving by
189 * @iif: ifindex of device we arrived on
190 * @h: Transport layer header
191 * @nh: Network layer header
192 * @mac: Link layer header
193 * @dst: destination entry
194 * @sp: the security path, used for xfrm
195 * @cb: Control buffer. Free for use by every layer. Put private vars here
196 * @len: Length of actual data
197 * @data_len: Data length
198 * @mac_len: Length of link layer header
199 * @csum: Checksum
200 * @local_df: allow local fragmentation
201 * @cloned: Head may be cloned (check refcnt to be sure)
202 * @nohdr: Payload reference only, must not modify header
203 * @pkt_type: Packet class
204 * @fclone: skbuff clone status
205 * @ip_summed: Driver fed us an IP checksum
206 * @priority: Packet queueing priority
207 * @users: User count - see {datagram,tcp}.c
208 * @protocol: Packet protocol from driver
209 * @truesize: Buffer size
210 * @head: Head of buffer
211 * @data: Data head pointer
212 * @tail: Tail pointer
213 * @end: End pointer
214 * @destructor: Destruct function
215 * @mark: Generic packet mark
216 * @nfct: Associated connection, if any
217 * @ipvs_property: skbuff is owned by ipvs
218 * @nfctinfo: Relationship of this skb to the connection
219 * @nfct_reasm: netfilter conntrack re-assembly pointer
220 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
221 * @tc_index: Traffic control index
222 * @tc_verd: traffic control verdict
223 * @dma_cookie: a cookie to one of several possible DMA operations
224 * done by skb DMA functions
225 * @secmark: security marking
228 struct sk_buff {
229 /* These two members must be first. */
230 struct sk_buff *next;
231 struct sk_buff *prev;
233 struct sock *sk;
234 ktime_t tstamp;
235 struct net_device *dev;
236 int iif;
237 /* 4 byte hole on 64 bit*/
239 union {
240 unsigned char *raw;
241 } h;
243 union {
244 unsigned char *raw;
245 } nh;
247 union {
248 unsigned char *raw;
249 } mac;
251 struct dst_entry *dst;
252 struct sec_path *sp;
255 * This is the control buffer. It is free to use for every
256 * layer. Please put your private variables there. If you
257 * want to keep them across layers you have to do a skb_clone()
258 * first. This is owned by whoever has the skb queued ATM.
260 char cb[48];
262 unsigned int len,
263 data_len,
264 mac_len;
265 union {
266 __wsum csum;
267 __u32 csum_offset;
269 __u32 priority;
270 __u8 local_df:1,
271 cloned:1,
272 ip_summed:2,
273 nohdr:1,
274 nfctinfo:3;
275 __u8 pkt_type:3,
276 fclone:2,
277 ipvs_property:1;
278 __be16 protocol;
280 void (*destructor)(struct sk_buff *skb);
281 #ifdef CONFIG_NETFILTER
282 struct nf_conntrack *nfct;
283 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
284 struct sk_buff *nfct_reasm;
285 #endif
286 #ifdef CONFIG_BRIDGE_NETFILTER
287 struct nf_bridge_info *nf_bridge;
288 #endif
289 #endif /* CONFIG_NETFILTER */
290 #ifdef CONFIG_NET_SCHED
291 __u16 tc_index; /* traffic control index */
292 #ifdef CONFIG_NET_CLS_ACT
293 __u16 tc_verd; /* traffic control verdict */
294 #endif
295 #endif
296 #ifdef CONFIG_NET_DMA
297 dma_cookie_t dma_cookie;
298 #endif
299 #ifdef CONFIG_NETWORK_SECMARK
300 __u32 secmark;
301 #endif
303 __u32 mark;
305 /* These elements must be at the end, see alloc_skb() for details. */
306 unsigned int truesize;
307 atomic_t users;
308 unsigned char *head,
309 *data,
310 *tail,
311 *end;
314 #ifdef __KERNEL__
316 * Handling routines are only of interest to the kernel
318 #include <linux/slab.h>
320 #include <asm/system.h>
322 extern void kfree_skb(struct sk_buff *skb);
323 extern void __kfree_skb(struct sk_buff *skb);
324 extern struct sk_buff *__alloc_skb(unsigned int size,
325 gfp_t priority, int fclone, int node);
326 static inline struct sk_buff *alloc_skb(unsigned int size,
327 gfp_t priority)
329 return __alloc_skb(size, priority, 0, -1);
332 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
333 gfp_t priority)
335 return __alloc_skb(size, priority, 1, -1);
338 extern void kfree_skbmem(struct sk_buff *skb);
339 extern struct sk_buff *skb_clone(struct sk_buff *skb,
340 gfp_t priority);
341 extern struct sk_buff *skb_copy(const struct sk_buff *skb,
342 gfp_t priority);
343 extern struct sk_buff *pskb_copy(struct sk_buff *skb,
344 gfp_t gfp_mask);
345 extern int pskb_expand_head(struct sk_buff *skb,
346 int nhead, int ntail,
347 gfp_t gfp_mask);
348 extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
349 unsigned int headroom);
350 extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
351 int newheadroom, int newtailroom,
352 gfp_t priority);
353 extern int skb_pad(struct sk_buff *skb, int pad);
354 #define dev_kfree_skb(a) kfree_skb(a)
355 extern void skb_over_panic(struct sk_buff *skb, int len,
356 void *here);
357 extern void skb_under_panic(struct sk_buff *skb, int len,
358 void *here);
359 extern void skb_truesize_bug(struct sk_buff *skb);
361 static inline void skb_truesize_check(struct sk_buff *skb)
363 if (unlikely((int)skb->truesize < sizeof(struct sk_buff) + skb->len))
364 skb_truesize_bug(skb);
367 extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
368 int getfrag(void *from, char *to, int offset,
369 int len,int odd, struct sk_buff *skb),
370 void *from, int length);
372 struct skb_seq_state
374 __u32 lower_offset;
375 __u32 upper_offset;
376 __u32 frag_idx;
377 __u32 stepped_offset;
378 struct sk_buff *root_skb;
379 struct sk_buff *cur_skb;
380 __u8 *frag_data;
383 extern void skb_prepare_seq_read(struct sk_buff *skb,
384 unsigned int from, unsigned int to,
385 struct skb_seq_state *st);
386 extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
387 struct skb_seq_state *st);
388 extern void skb_abort_seq_read(struct skb_seq_state *st);
390 extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
391 unsigned int to, struct ts_config *config,
392 struct ts_state *state);
394 /* Internal */
395 #define skb_shinfo(SKB) ((struct skb_shared_info *)((SKB)->end))
398 * skb_queue_empty - check if a queue is empty
399 * @list: queue head
401 * Returns true if the queue is empty, false otherwise.
403 static inline int skb_queue_empty(const struct sk_buff_head *list)
405 return list->next == (struct sk_buff *)list;
409 * skb_get - reference buffer
410 * @skb: buffer to reference
412 * Makes another reference to a socket buffer and returns a pointer
413 * to the buffer.
415 static inline struct sk_buff *skb_get(struct sk_buff *skb)
417 atomic_inc(&skb->users);
418 return skb;
422 * If users == 1, we are the only owner and are can avoid redundant
423 * atomic change.
427 * skb_cloned - is the buffer a clone
428 * @skb: buffer to check
430 * Returns true if the buffer was generated with skb_clone() and is
431 * one of multiple shared copies of the buffer. Cloned buffers are
432 * shared data so must not be written to under normal circumstances.
434 static inline int skb_cloned(const struct sk_buff *skb)
436 return skb->cloned &&
437 (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
441 * skb_header_cloned - is the header a clone
442 * @skb: buffer to check
444 * Returns true if modifying the header part of the buffer requires
445 * the data to be copied.
447 static inline int skb_header_cloned(const struct sk_buff *skb)
449 int dataref;
451 if (!skb->cloned)
452 return 0;
454 dataref = atomic_read(&skb_shinfo(skb)->dataref);
455 dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
456 return dataref != 1;
460 * skb_header_release - release reference to header
461 * @skb: buffer to operate on
463 * Drop a reference to the header part of the buffer. This is done
464 * by acquiring a payload reference. You must not read from the header
465 * part of skb->data after this.
467 static inline void skb_header_release(struct sk_buff *skb)
469 BUG_ON(skb->nohdr);
470 skb->nohdr = 1;
471 atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
475 * skb_shared - is the buffer shared
476 * @skb: buffer to check
478 * Returns true if more than one person has a reference to this
479 * buffer.
481 static inline int skb_shared(const struct sk_buff *skb)
483 return atomic_read(&skb->users) != 1;
487 * skb_share_check - check if buffer is shared and if so clone it
488 * @skb: buffer to check
489 * @pri: priority for memory allocation
491 * If the buffer is shared the buffer is cloned and the old copy
492 * drops a reference. A new clone with a single reference is returned.
493 * If the buffer is not shared the original buffer is returned. When
494 * being called from interrupt status or with spinlocks held pri must
495 * be GFP_ATOMIC.
497 * NULL is returned on a memory allocation failure.
499 static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
500 gfp_t pri)
502 might_sleep_if(pri & __GFP_WAIT);
503 if (skb_shared(skb)) {
504 struct sk_buff *nskb = skb_clone(skb, pri);
505 kfree_skb(skb);
506 skb = nskb;
508 return skb;
512 * Copy shared buffers into a new sk_buff. We effectively do COW on
513 * packets to handle cases where we have a local reader and forward
514 * and a couple of other messy ones. The normal one is tcpdumping
515 * a packet thats being forwarded.
519 * skb_unshare - make a copy of a shared buffer
520 * @skb: buffer to check
521 * @pri: priority for memory allocation
523 * If the socket buffer is a clone then this function creates a new
524 * copy of the data, drops a reference count on the old copy and returns
525 * the new copy with the reference count at 1. If the buffer is not a clone
526 * the original buffer is returned. When called with a spinlock held or
527 * from interrupt state @pri must be %GFP_ATOMIC
529 * %NULL is returned on a memory allocation failure.
531 static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
532 gfp_t pri)
534 might_sleep_if(pri & __GFP_WAIT);
535 if (skb_cloned(skb)) {
536 struct sk_buff *nskb = skb_copy(skb, pri);
537 kfree_skb(skb); /* Free our shared copy */
538 skb = nskb;
540 return skb;
544 * skb_peek
545 * @list_: list to peek at
547 * Peek an &sk_buff. Unlike most other operations you _MUST_
548 * be careful with this one. A peek leaves the buffer on the
549 * list and someone else may run off with it. You must hold
550 * the appropriate locks or have a private queue to do this.
552 * Returns %NULL for an empty list or a pointer to the head element.
553 * The reference count is not incremented and the reference is therefore
554 * volatile. Use with caution.
556 static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
558 struct sk_buff *list = ((struct sk_buff *)list_)->next;
559 if (list == (struct sk_buff *)list_)
560 list = NULL;
561 return list;
565 * skb_peek_tail
566 * @list_: list to peek at
568 * Peek an &sk_buff. Unlike most other operations you _MUST_
569 * be careful with this one. A peek leaves the buffer on the
570 * list and someone else may run off with it. You must hold
571 * the appropriate locks or have a private queue to do this.
573 * Returns %NULL for an empty list or a pointer to the tail element.
574 * The reference count is not incremented and the reference is therefore
575 * volatile. Use with caution.
577 static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
579 struct sk_buff *list = ((struct sk_buff *)list_)->prev;
580 if (list == (struct sk_buff *)list_)
581 list = NULL;
582 return list;
586 * skb_queue_len - get queue length
587 * @list_: list to measure
589 * Return the length of an &sk_buff queue.
591 static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
593 return list_->qlen;
597 * This function creates a split out lock class for each invocation;
598 * this is needed for now since a whole lot of users of the skb-queue
599 * infrastructure in drivers have different locking usage (in hardirq)
600 * than the networking core (in softirq only). In the long run either the
601 * network layer or drivers should need annotation to consolidate the
602 * main types of usage into 3 classes.
604 static inline void skb_queue_head_init(struct sk_buff_head *list)
606 spin_lock_init(&list->lock);
607 list->prev = list->next = (struct sk_buff *)list;
608 list->qlen = 0;
611 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
612 struct lock_class_key *class)
614 skb_queue_head_init(list);
615 lockdep_set_class(&list->lock, class);
619 * Insert an sk_buff at the start of a list.
621 * The "__skb_xxxx()" functions are the non-atomic ones that
622 * can only be called with interrupts disabled.
626 * __skb_queue_after - queue a buffer at the list head
627 * @list: list to use
628 * @prev: place after this buffer
629 * @newsk: buffer to queue
631 * Queue a buffer int the middle of a list. This function takes no locks
632 * and you must therefore hold required locks before calling it.
634 * A buffer cannot be placed on two lists at the same time.
636 static inline void __skb_queue_after(struct sk_buff_head *list,
637 struct sk_buff *prev,
638 struct sk_buff *newsk)
640 struct sk_buff *next;
641 list->qlen++;
643 next = prev->next;
644 newsk->next = next;
645 newsk->prev = prev;
646 next->prev = prev->next = newsk;
650 * __skb_queue_head - queue a buffer at the list head
651 * @list: list to use
652 * @newsk: buffer to queue
654 * Queue a buffer at the start of a list. This function takes no locks
655 * and you must therefore hold required locks before calling it.
657 * A buffer cannot be placed on two lists at the same time.
659 extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
660 static inline void __skb_queue_head(struct sk_buff_head *list,
661 struct sk_buff *newsk)
663 __skb_queue_after(list, (struct sk_buff *)list, newsk);
667 * __skb_queue_tail - queue a buffer at the list tail
668 * @list: list to use
669 * @newsk: buffer to queue
671 * Queue a buffer at the end of a list. This function takes no locks
672 * and you must therefore hold required locks before calling it.
674 * A buffer cannot be placed on two lists at the same time.
676 extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
677 static inline void __skb_queue_tail(struct sk_buff_head *list,
678 struct sk_buff *newsk)
680 struct sk_buff *prev, *next;
682 list->qlen++;
683 next = (struct sk_buff *)list;
684 prev = next->prev;
685 newsk->next = next;
686 newsk->prev = prev;
687 next->prev = prev->next = newsk;
692 * __skb_dequeue - remove from the head of the queue
693 * @list: list to dequeue from
695 * Remove the head of the list. This function does not take any locks
696 * so must be used with appropriate locks held only. The head item is
697 * returned or %NULL if the list is empty.
699 extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
700 static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
702 struct sk_buff *next, *prev, *result;
704 prev = (struct sk_buff *) list;
705 next = prev->next;
706 result = NULL;
707 if (next != prev) {
708 result = next;
709 next = next->next;
710 list->qlen--;
711 next->prev = prev;
712 prev->next = next;
713 result->next = result->prev = NULL;
715 return result;
720 * Insert a packet on a list.
722 extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
723 static inline void __skb_insert(struct sk_buff *newsk,
724 struct sk_buff *prev, struct sk_buff *next,
725 struct sk_buff_head *list)
727 newsk->next = next;
728 newsk->prev = prev;
729 next->prev = prev->next = newsk;
730 list->qlen++;
734 * Place a packet after a given packet in a list.
736 extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
737 static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
739 __skb_insert(newsk, old, old->next, list);
743 * remove sk_buff from list. _Must_ be called atomically, and with
744 * the list known..
746 extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
747 static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
749 struct sk_buff *next, *prev;
751 list->qlen--;
752 next = skb->next;
753 prev = skb->prev;
754 skb->next = skb->prev = NULL;
755 next->prev = prev;
756 prev->next = next;
760 /* XXX: more streamlined implementation */
763 * __skb_dequeue_tail - remove from the tail of the queue
764 * @list: list to dequeue from
766 * Remove the tail of the list. This function does not take any locks
767 * so must be used with appropriate locks held only. The tail item is
768 * returned or %NULL if the list is empty.
770 extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
771 static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
773 struct sk_buff *skb = skb_peek_tail(list);
774 if (skb)
775 __skb_unlink(skb, list);
776 return skb;
780 static inline int skb_is_nonlinear(const struct sk_buff *skb)
782 return skb->data_len;
785 static inline unsigned int skb_headlen(const struct sk_buff *skb)
787 return skb->len - skb->data_len;
790 static inline int skb_pagelen(const struct sk_buff *skb)
792 int i, len = 0;
794 for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
795 len += skb_shinfo(skb)->frags[i].size;
796 return len + skb_headlen(skb);
799 static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
800 struct page *page, int off, int size)
802 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
804 frag->page = page;
805 frag->page_offset = off;
806 frag->size = size;
807 skb_shinfo(skb)->nr_frags = i + 1;
810 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
811 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
812 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
815 * Add data to an sk_buff
817 static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
819 unsigned char *tmp = skb->tail;
820 SKB_LINEAR_ASSERT(skb);
821 skb->tail += len;
822 skb->len += len;
823 return tmp;
827 * skb_put - add data to a buffer
828 * @skb: buffer to use
829 * @len: amount of data to add
831 * This function extends the used data area of the buffer. If this would
832 * exceed the total buffer size the kernel will panic. A pointer to the
833 * first byte of the extra data is returned.
835 static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len)
837 unsigned char *tmp = skb->tail;
838 SKB_LINEAR_ASSERT(skb);
839 skb->tail += len;
840 skb->len += len;
841 if (unlikely(skb->tail>skb->end))
842 skb_over_panic(skb, len, current_text_addr());
843 return tmp;
846 static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
848 skb->data -= len;
849 skb->len += len;
850 return skb->data;
854 * skb_push - add data to the start of a buffer
855 * @skb: buffer to use
856 * @len: amount of data to add
858 * This function extends the used data area of the buffer at the buffer
859 * start. If this would exceed the total buffer headroom the kernel will
860 * panic. A pointer to the first byte of the extra data is returned.
862 static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len)
864 skb->data -= len;
865 skb->len += len;
866 if (unlikely(skb->data<skb->head))
867 skb_under_panic(skb, len, current_text_addr());
868 return skb->data;
871 static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
873 skb->len -= len;
874 BUG_ON(skb->len < skb->data_len);
875 return skb->data += len;
879 * skb_pull - remove data from the start of a buffer
880 * @skb: buffer to use
881 * @len: amount of data to remove
883 * This function removes data from the start of a buffer, returning
884 * the memory to the headroom. A pointer to the next data in the buffer
885 * is returned. Once the data has been pulled future pushes will overwrite
886 * the old data.
888 static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len)
890 return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
893 extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
895 static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
897 if (len > skb_headlen(skb) &&
898 !__pskb_pull_tail(skb, len-skb_headlen(skb)))
899 return NULL;
900 skb->len -= len;
901 return skb->data += len;
904 static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
906 return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
909 static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
911 if (likely(len <= skb_headlen(skb)))
912 return 1;
913 if (unlikely(len > skb->len))
914 return 0;
915 return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL;
919 * skb_headroom - bytes at buffer head
920 * @skb: buffer to check
922 * Return the number of bytes of free space at the head of an &sk_buff.
924 static inline int skb_headroom(const struct sk_buff *skb)
926 return skb->data - skb->head;
930 * skb_tailroom - bytes at buffer end
931 * @skb: buffer to check
933 * Return the number of bytes of free space at the tail of an sk_buff
935 static inline int skb_tailroom(const struct sk_buff *skb)
937 return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
941 * skb_reserve - adjust headroom
942 * @skb: buffer to alter
943 * @len: bytes to move
945 * Increase the headroom of an empty &sk_buff by reducing the tail
946 * room. This is only allowed for an empty buffer.
948 static inline void skb_reserve(struct sk_buff *skb, int len)
950 skb->data += len;
951 skb->tail += len;
954 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
956 return skb->h.raw;
959 static inline void skb_reset_transport_header(struct sk_buff *skb)
961 skb->h.raw = skb->data;
964 static inline void skb_set_transport_header(struct sk_buff *skb,
965 const int offset)
967 skb->h.raw = skb->data + offset;
970 static inline int skb_transport_offset(const struct sk_buff *skb)
972 return skb->h.raw - skb->data;
975 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
977 return skb->nh.raw;
980 static inline void skb_reset_network_header(struct sk_buff *skb)
982 skb->nh.raw = skb->data;
985 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
987 skb->nh.raw = skb->data + offset;
990 static inline int skb_network_offset(const struct sk_buff *skb)
992 return skb->nh.raw - skb->data;
995 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
997 return skb->mac.raw;
1000 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1002 return skb->mac.raw != NULL;
1005 static inline void skb_reset_mac_header(struct sk_buff *skb)
1007 skb->mac.raw = skb->data;
1010 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1012 skb->mac.raw = skb->data + offset;
1016 * CPUs often take a performance hit when accessing unaligned memory
1017 * locations. The actual performance hit varies, it can be small if the
1018 * hardware handles it or large if we have to take an exception and fix it
1019 * in software.
1021 * Since an ethernet header is 14 bytes network drivers often end up with
1022 * the IP header at an unaligned offset. The IP header can be aligned by
1023 * shifting the start of the packet by 2 bytes. Drivers should do this
1024 * with:
1026 * skb_reserve(NET_IP_ALIGN);
1028 * The downside to this alignment of the IP header is that the DMA is now
1029 * unaligned. On some architectures the cost of an unaligned DMA is high
1030 * and this cost outweighs the gains made by aligning the IP header.
1032 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1033 * to be overridden.
1035 #ifndef NET_IP_ALIGN
1036 #define NET_IP_ALIGN 2
1037 #endif
1040 * The networking layer reserves some headroom in skb data (via
1041 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1042 * the header has to grow. In the default case, if the header has to grow
1043 * 16 bytes or less we avoid the reallocation.
1045 * Unfortunately this headroom changes the DMA alignment of the resulting
1046 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1047 * on some architectures. An architecture can override this value,
1048 * perhaps setting it to a cacheline in size (since that will maintain
1049 * cacheline alignment of the DMA). It must be a power of 2.
1051 * Various parts of the networking layer expect at least 16 bytes of
1052 * headroom, you should not reduce this.
1054 #ifndef NET_SKB_PAD
1055 #define NET_SKB_PAD 16
1056 #endif
1058 extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
1060 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
1062 if (unlikely(skb->data_len)) {
1063 WARN_ON(1);
1064 return;
1066 skb->len = len;
1067 skb->tail = skb->data + len;
1071 * skb_trim - remove end from a buffer
1072 * @skb: buffer to alter
1073 * @len: new length
1075 * Cut the length of a buffer down by removing data from the tail. If
1076 * the buffer is already under the length specified it is not modified.
1077 * The skb must be linear.
1079 static inline void skb_trim(struct sk_buff *skb, unsigned int len)
1081 if (skb->len > len)
1082 __skb_trim(skb, len);
1086 static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
1088 if (skb->data_len)
1089 return ___pskb_trim(skb, len);
1090 __skb_trim(skb, len);
1091 return 0;
1094 static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
1096 return (len < skb->len) ? __pskb_trim(skb, len) : 0;
1100 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1101 * @skb: buffer to alter
1102 * @len: new length
1104 * This is identical to pskb_trim except that the caller knows that
1105 * the skb is not cloned so we should never get an error due to out-
1106 * of-memory.
1108 static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
1110 int err = pskb_trim(skb, len);
1111 BUG_ON(err);
1115 * skb_orphan - orphan a buffer
1116 * @skb: buffer to orphan
1118 * If a buffer currently has an owner then we call the owner's
1119 * destructor function and make the @skb unowned. The buffer continues
1120 * to exist but is no longer charged to its former owner.
1122 static inline void skb_orphan(struct sk_buff *skb)
1124 if (skb->destructor)
1125 skb->destructor(skb);
1126 skb->destructor = NULL;
1127 skb->sk = NULL;
1131 * __skb_queue_purge - empty a list
1132 * @list: list to empty
1134 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1135 * the list and one reference dropped. This function does not take the
1136 * list lock and the caller must hold the relevant locks to use it.
1138 extern void skb_queue_purge(struct sk_buff_head *list);
1139 static inline void __skb_queue_purge(struct sk_buff_head *list)
1141 struct sk_buff *skb;
1142 while ((skb = __skb_dequeue(list)) != NULL)
1143 kfree_skb(skb);
1147 * __dev_alloc_skb - allocate an skbuff for receiving
1148 * @length: length to allocate
1149 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1151 * Allocate a new &sk_buff and assign it a usage count of one. The
1152 * buffer has unspecified headroom built in. Users should allocate
1153 * the headroom they think they need without accounting for the
1154 * built in space. The built in space is used for optimisations.
1156 * %NULL is returned if there is no free memory.
1158 static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
1159 gfp_t gfp_mask)
1161 struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
1162 if (likely(skb))
1163 skb_reserve(skb, NET_SKB_PAD);
1164 return skb;
1168 * dev_alloc_skb - allocate an skbuff for receiving
1169 * @length: length to allocate
1171 * Allocate a new &sk_buff and assign it a usage count of one. The
1172 * buffer has unspecified headroom built in. Users should allocate
1173 * the headroom they think they need without accounting for the
1174 * built in space. The built in space is used for optimisations.
1176 * %NULL is returned if there is no free memory. Although this function
1177 * allocates memory it can be called from an interrupt.
1179 static inline struct sk_buff *dev_alloc_skb(unsigned int length)
1181 return __dev_alloc_skb(length, GFP_ATOMIC);
1184 extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
1185 unsigned int length, gfp_t gfp_mask);
1188 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1189 * @dev: network device to receive on
1190 * @length: length to allocate
1192 * Allocate a new &sk_buff and assign it a usage count of one. The
1193 * buffer has unspecified headroom built in. Users should allocate
1194 * the headroom they think they need without accounting for the
1195 * built in space. The built in space is used for optimisations.
1197 * %NULL is returned if there is no free memory. Although this function
1198 * allocates memory it can be called from an interrupt.
1200 static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
1201 unsigned int length)
1203 return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
1207 * skb_cow - copy header of skb when it is required
1208 * @skb: buffer to cow
1209 * @headroom: needed headroom
1211 * If the skb passed lacks sufficient headroom or its data part
1212 * is shared, data is reallocated. If reallocation fails, an error
1213 * is returned and original skb is not changed.
1215 * The result is skb with writable area skb->head...skb->tail
1216 * and at least @headroom of space at head.
1218 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
1220 int delta = (headroom > NET_SKB_PAD ? headroom : NET_SKB_PAD) -
1221 skb_headroom(skb);
1223 if (delta < 0)
1224 delta = 0;
1226 if (delta || skb_cloned(skb))
1227 return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) &
1228 ~(NET_SKB_PAD-1), 0, GFP_ATOMIC);
1229 return 0;
1233 * skb_padto - pad an skbuff up to a minimal size
1234 * @skb: buffer to pad
1235 * @len: minimal length
1237 * Pads up a buffer to ensure the trailing bytes exist and are
1238 * blanked. If the buffer already contains sufficient data it
1239 * is untouched. Otherwise it is extended. Returns zero on
1240 * success. The skb is freed on error.
1243 static inline int skb_padto(struct sk_buff *skb, unsigned int len)
1245 unsigned int size = skb->len;
1246 if (likely(size >= len))
1247 return 0;
1248 return skb_pad(skb, len-size);
1251 static inline int skb_add_data(struct sk_buff *skb,
1252 char __user *from, int copy)
1254 const int off = skb->len;
1256 if (skb->ip_summed == CHECKSUM_NONE) {
1257 int err = 0;
1258 __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
1259 copy, 0, &err);
1260 if (!err) {
1261 skb->csum = csum_block_add(skb->csum, csum, off);
1262 return 0;
1264 } else if (!copy_from_user(skb_put(skb, copy), from, copy))
1265 return 0;
1267 __skb_trim(skb, off);
1268 return -EFAULT;
1271 static inline int skb_can_coalesce(struct sk_buff *skb, int i,
1272 struct page *page, int off)
1274 if (i) {
1275 struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
1277 return page == frag->page &&
1278 off == frag->page_offset + frag->size;
1280 return 0;
1283 static inline int __skb_linearize(struct sk_buff *skb)
1285 return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
1289 * skb_linearize - convert paged skb to linear one
1290 * @skb: buffer to linarize
1292 * If there is no free memory -ENOMEM is returned, otherwise zero
1293 * is returned and the old skb data released.
1295 static inline int skb_linearize(struct sk_buff *skb)
1297 return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
1301 * skb_linearize_cow - make sure skb is linear and writable
1302 * @skb: buffer to process
1304 * If there is no free memory -ENOMEM is returned, otherwise zero
1305 * is returned and the old skb data released.
1307 static inline int skb_linearize_cow(struct sk_buff *skb)
1309 return skb_is_nonlinear(skb) || skb_cloned(skb) ?
1310 __skb_linearize(skb) : 0;
1314 * skb_postpull_rcsum - update checksum for received skb after pull
1315 * @skb: buffer to update
1316 * @start: start of data before pull
1317 * @len: length of data pulled
1319 * After doing a pull on a received packet, you need to call this to
1320 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
1321 * CHECKSUM_NONE so that it can be recomputed from scratch.
1324 static inline void skb_postpull_rcsum(struct sk_buff *skb,
1325 const void *start, unsigned int len)
1327 if (skb->ip_summed == CHECKSUM_COMPLETE)
1328 skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
1331 unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
1334 * pskb_trim_rcsum - trim received skb and update checksum
1335 * @skb: buffer to trim
1336 * @len: new length
1338 * This is exactly the same as pskb_trim except that it ensures the
1339 * checksum of received packets are still valid after the operation.
1342 static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
1344 if (likely(len >= skb->len))
1345 return 0;
1346 if (skb->ip_summed == CHECKSUM_COMPLETE)
1347 skb->ip_summed = CHECKSUM_NONE;
1348 return __pskb_trim(skb, len);
1351 #define skb_queue_walk(queue, skb) \
1352 for (skb = (queue)->next; \
1353 prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
1354 skb = skb->next)
1356 #define skb_queue_reverse_walk(queue, skb) \
1357 for (skb = (queue)->prev; \
1358 prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
1359 skb = skb->prev)
1362 extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
1363 int noblock, int *err);
1364 extern unsigned int datagram_poll(struct file *file, struct socket *sock,
1365 struct poll_table_struct *wait);
1366 extern int skb_copy_datagram_iovec(const struct sk_buff *from,
1367 int offset, struct iovec *to,
1368 int size);
1369 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
1370 int hlen,
1371 struct iovec *iov);
1372 extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
1373 extern void skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
1374 unsigned int flags);
1375 extern __wsum skb_checksum(const struct sk_buff *skb, int offset,
1376 int len, __wsum csum);
1377 extern int skb_copy_bits(const struct sk_buff *skb, int offset,
1378 void *to, int len);
1379 extern int skb_store_bits(const struct sk_buff *skb, int offset,
1380 void *from, int len);
1381 extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb,
1382 int offset, u8 *to, int len,
1383 __wsum csum);
1384 extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
1385 extern void skb_split(struct sk_buff *skb,
1386 struct sk_buff *skb1, const u32 len);
1388 extern struct sk_buff *skb_segment(struct sk_buff *skb, int features);
1390 static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
1391 int len, void *buffer)
1393 int hlen = skb_headlen(skb);
1395 if (hlen - offset >= len)
1396 return skb->data + offset;
1398 if (skb_copy_bits(skb, offset, buffer, len) < 0)
1399 return NULL;
1401 return buffer;
1404 extern void skb_init(void);
1405 extern void skb_add_mtu(int mtu);
1408 * skb_get_timestamp - get timestamp from a skb
1409 * @skb: skb to get stamp from
1410 * @stamp: pointer to struct timeval to store stamp in
1412 * Timestamps are stored in the skb as offsets to a base timestamp.
1413 * This function converts the offset back to a struct timeval and stores
1414 * it in stamp.
1416 static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
1418 *stamp = ktime_to_timeval(skb->tstamp);
1421 static inline void __net_timestamp(struct sk_buff *skb)
1423 skb->tstamp = ktime_get_real();
1427 extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
1428 extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
1431 * skb_checksum_complete - Calculate checksum of an entire packet
1432 * @skb: packet to process
1434 * This function calculates the checksum over the entire packet plus
1435 * the value of skb->csum. The latter can be used to supply the
1436 * checksum of a pseudo header as used by TCP/UDP. It returns the
1437 * checksum.
1439 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
1440 * this function can be used to verify that checksum on received
1441 * packets. In that case the function should return zero if the
1442 * checksum is correct. In particular, this function will return zero
1443 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
1444 * hardware has already verified the correctness of the checksum.
1446 static inline unsigned int skb_checksum_complete(struct sk_buff *skb)
1448 return skb->ip_summed != CHECKSUM_UNNECESSARY &&
1449 __skb_checksum_complete(skb);
1452 #ifdef CONFIG_NETFILTER
1453 static inline void nf_conntrack_put(struct nf_conntrack *nfct)
1455 if (nfct && atomic_dec_and_test(&nfct->use))
1456 nfct->destroy(nfct);
1458 static inline void nf_conntrack_get(struct nf_conntrack *nfct)
1460 if (nfct)
1461 atomic_inc(&nfct->use);
1463 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1464 static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
1466 if (skb)
1467 atomic_inc(&skb->users);
1469 static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
1471 if (skb)
1472 kfree_skb(skb);
1474 #endif
1475 #ifdef CONFIG_BRIDGE_NETFILTER
1476 static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
1478 if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
1479 kfree(nf_bridge);
1481 static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
1483 if (nf_bridge)
1484 atomic_inc(&nf_bridge->use);
1486 #endif /* CONFIG_BRIDGE_NETFILTER */
1487 static inline void nf_reset(struct sk_buff *skb)
1489 nf_conntrack_put(skb->nfct);
1490 skb->nfct = NULL;
1491 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1492 nf_conntrack_put_reasm(skb->nfct_reasm);
1493 skb->nfct_reasm = NULL;
1494 #endif
1495 #ifdef CONFIG_BRIDGE_NETFILTER
1496 nf_bridge_put(skb->nf_bridge);
1497 skb->nf_bridge = NULL;
1498 #endif
1501 /* Note: This doesn't put any conntrack and bridge info in dst. */
1502 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1504 dst->nfct = src->nfct;
1505 nf_conntrack_get(src->nfct);
1506 dst->nfctinfo = src->nfctinfo;
1507 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1508 dst->nfct_reasm = src->nfct_reasm;
1509 nf_conntrack_get_reasm(src->nfct_reasm);
1510 #endif
1511 #ifdef CONFIG_BRIDGE_NETFILTER
1512 dst->nf_bridge = src->nf_bridge;
1513 nf_bridge_get(src->nf_bridge);
1514 #endif
1517 static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1519 nf_conntrack_put(dst->nfct);
1520 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1521 nf_conntrack_put_reasm(dst->nfct_reasm);
1522 #endif
1523 #ifdef CONFIG_BRIDGE_NETFILTER
1524 nf_bridge_put(dst->nf_bridge);
1525 #endif
1526 __nf_copy(dst, src);
1529 #else /* CONFIG_NETFILTER */
1530 static inline void nf_reset(struct sk_buff *skb) {}
1531 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src) {}
1532 static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) {}
1533 #endif /* CONFIG_NETFILTER */
1535 #ifdef CONFIG_NETWORK_SECMARK
1536 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1538 to->secmark = from->secmark;
1541 static inline void skb_init_secmark(struct sk_buff *skb)
1543 skb->secmark = 0;
1545 #else
1546 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1549 static inline void skb_init_secmark(struct sk_buff *skb)
1551 #endif
1553 static inline int skb_is_gso(const struct sk_buff *skb)
1555 return skb_shinfo(skb)->gso_size;
1558 #endif /* __KERNEL__ */
1559 #endif /* _LINUX_SKBUFF_H */