2 * Definitions for the 'struct sk_buff' memory handlers.
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 /* Don't change this without changing skb_csum_unnecessary! */
36 #define CHECKSUM_NONE 0
37 #define CHECKSUM_UNNECESSARY 1
38 #define CHECKSUM_COMPLETE 2
39 #define CHECKSUM_PARTIAL 3
41 #define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \
42 ~(SMP_CACHE_BYTES - 1))
43 #define SKB_WITH_OVERHEAD(X) \
44 ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
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,
67 * PARTIAL: identical to the case for output below. This may occur
68 * on a packet received directly from another Linux OS, e.g.,
69 * a virtualised Linux kernel on the same host. The packet can
70 * be treated in the same way as UNNECESSARY except that on
71 * output (i.e., forwarding) the checksum must be filled in
72 * by the OS or the hardware.
74 * B. Checksumming on output.
76 * NONE: skb is checksummed by protocol or csum is not required.
78 * PARTIAL: device is required to csum packet as seen by hard_start_xmit
79 * from skb->csum_start to the end and to record the checksum
80 * at skb->csum_start + skb->csum_offset.
82 * Device must show its capabilities in dev->features, set
83 * at device setup time.
84 * NETIF_F_HW_CSUM - it is clever device, it is able to checksum
86 * NETIF_F_NO_CSUM - loopback or reliable single hop media.
87 * NETIF_F_IP_CSUM - device is dumb. It is able to csum only
88 * TCP/UDP over IPv4. Sigh. Vendors like this
89 * way by an unknown reason. Though, see comment above
90 * about CHECKSUM_UNNECESSARY. 8)
91 * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead.
93 * Any questions? No questions, good. --ANK
98 struct pipe_inode_info;
100 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
101 struct nf_conntrack {
106 #ifdef CONFIG_BRIDGE_NETFILTER
107 struct nf_bridge_info {
109 struct net_device *physindev;
110 struct net_device *physoutdev;
112 unsigned long data[32 / sizeof(unsigned long)];
116 struct sk_buff_head {
117 /* These two members must be first. */
118 struct sk_buff *next;
119 struct sk_buff *prev;
127 /* To allow 64K frame to be packed as single skb without frag_list */
128 #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2)
130 typedef struct skb_frag_struct skb_frag_t;
132 struct skb_frag_struct {
138 /* This data is invariant across clones and lives at
139 * the end of the header data, ie. at skb->end.
141 struct skb_shared_info {
143 unsigned short nr_frags;
144 unsigned short gso_size;
145 /* Warning: this field is not always filled in (UFO)! */
146 unsigned short gso_segs;
147 unsigned short gso_type;
149 struct sk_buff *frag_list;
150 skb_frag_t frags[MAX_SKB_FRAGS];
153 /* We divide dataref into two halves. The higher 16 bits hold references
154 * to the payload part of skb->data. The lower 16 bits hold references to
155 * the entire skb->data. A clone of a headerless skb holds the length of
156 * the header in skb->hdr_len.
158 * All users must obey the rule that the skb->data reference count must be
159 * greater than or equal to the payload reference count.
161 * Holding a reference to the payload part means that the user does not
162 * care about modifications to the header part of skb->data.
164 #define SKB_DATAREF_SHIFT 16
165 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
169 SKB_FCLONE_UNAVAILABLE,
175 SKB_GSO_TCPV4 = 1 << 0,
176 SKB_GSO_UDP = 1 << 1,
178 /* This indicates the skb is from an untrusted source. */
179 SKB_GSO_DODGY = 1 << 2,
181 /* This indicates the tcp segment has CWR set. */
182 SKB_GSO_TCP_ECN = 1 << 3,
184 SKB_GSO_TCPV6 = 1 << 4,
187 #if BITS_PER_LONG > 32
188 #define NET_SKBUFF_DATA_USES_OFFSET 1
191 #ifdef NET_SKBUFF_DATA_USES_OFFSET
192 typedef unsigned int sk_buff_data_t;
194 typedef unsigned char *sk_buff_data_t;
198 * struct sk_buff - socket buffer
199 * @next: Next buffer in list
200 * @prev: Previous buffer in list
201 * @sk: Socket we are owned by
202 * @tstamp: Time we arrived
203 * @dev: Device we arrived on/are leaving by
204 * @transport_header: Transport layer header
205 * @network_header: Network layer header
206 * @mac_header: Link layer header
207 * @dst: destination entry
208 * @sp: the security path, used for xfrm
209 * @cb: Control buffer. Free for use by every layer. Put private vars here
210 * @len: Length of actual data
211 * @data_len: Data length
212 * @mac_len: Length of link layer header
213 * @hdr_len: writable header length of cloned skb
214 * @csum: Checksum (must include start/offset pair)
215 * @csum_start: Offset from skb->head where checksumming should start
216 * @csum_offset: Offset from csum_start where checksum should be stored
217 * @local_df: allow local fragmentation
218 * @cloned: Head may be cloned (check refcnt to be sure)
219 * @nohdr: Payload reference only, must not modify header
220 * @pkt_type: Packet class
221 * @fclone: skbuff clone status
222 * @ip_summed: Driver fed us an IP checksum
223 * @priority: Packet queueing priority
224 * @users: User count - see {datagram,tcp}.c
225 * @protocol: Packet protocol from driver
226 * @truesize: Buffer size
227 * @head: Head of buffer
228 * @data: Data head pointer
229 * @tail: Tail pointer
231 * @destructor: Destruct function
232 * @mark: Generic packet mark
233 * @nfct: Associated connection, if any
234 * @ipvs_property: skbuff is owned by ipvs
235 * @peeked: this packet has been seen already, so stats have been
236 * done for it, don't do them again
237 * @nf_trace: netfilter packet trace flag
238 * @nfctinfo: Relationship of this skb to the connection
239 * @nfct_reasm: netfilter conntrack re-assembly pointer
240 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
241 * @iif: ifindex of device we arrived on
242 * @queue_mapping: Queue mapping for multiqueue devices
243 * @tc_index: Traffic control index
244 * @tc_verd: traffic control verdict
245 * @dma_cookie: a cookie to one of several possible DMA operations
246 * done by skb DMA functions
247 * @secmark: security marking
251 /* These two members must be first. */
252 struct sk_buff *next;
253 struct sk_buff *prev;
257 struct net_device *dev;
260 struct dst_entry *dst;
261 struct rtable *rtable;
266 * This is the control buffer. It is free to use for every
267 * layer. Please put your private variables there. If you
268 * want to keep them across layers you have to do a skb_clone()
269 * first. This is owned by whoever has the skb queued ATM.
297 void (*destructor)(struct sk_buff *skb);
298 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
299 struct nf_conntrack *nfct;
300 struct sk_buff *nfct_reasm;
302 #ifdef CONFIG_BRIDGE_NETFILTER
303 struct nf_bridge_info *nf_bridge;
307 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
310 #ifdef CONFIG_NET_SCHED
311 __u16 tc_index; /* traffic control index */
312 #ifdef CONFIG_NET_CLS_ACT
313 __u16 tc_verd; /* traffic control verdict */
316 __u8 ndisc_nodetype:2;
319 #ifdef CONFIG_NET_DMA
320 dma_cookie_t dma_cookie;
322 #ifdef CONFIG_NETWORK_SECMARK
328 sk_buff_data_t transport_header;
329 sk_buff_data_t network_header;
330 sk_buff_data_t mac_header;
331 /* These elements must be at the end, see alloc_skb() for details. */
336 unsigned int truesize;
342 * Handling routines are only of interest to the kernel
344 #include <linux/slab.h>
346 #include <asm/system.h>
348 extern void kfree_skb(struct sk_buff *skb);
349 extern void __kfree_skb(struct sk_buff *skb);
350 extern struct sk_buff *__alloc_skb(unsigned int size,
351 gfp_t priority, int fclone, int node);
352 static inline struct sk_buff *alloc_skb(unsigned int size,
355 return __alloc_skb(size, priority, 0, -1);
358 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
361 return __alloc_skb(size, priority, 1, -1);
364 extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
365 extern struct sk_buff *skb_clone(struct sk_buff *skb,
367 extern struct sk_buff *skb_copy(const struct sk_buff *skb,
369 extern struct sk_buff *pskb_copy(struct sk_buff *skb,
371 extern int pskb_expand_head(struct sk_buff *skb,
372 int nhead, int ntail,
374 extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
375 unsigned int headroom);
376 extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
377 int newheadroom, int newtailroom,
379 extern int skb_to_sgvec(struct sk_buff *skb,
380 struct scatterlist *sg, int offset,
382 extern int skb_cow_data(struct sk_buff *skb, int tailbits,
383 struct sk_buff **trailer);
384 extern int skb_pad(struct sk_buff *skb, int pad);
385 #define dev_kfree_skb(a) kfree_skb(a)
386 extern void skb_over_panic(struct sk_buff *skb, int len,
388 extern void skb_under_panic(struct sk_buff *skb, int len,
390 extern void skb_truesize_bug(struct sk_buff *skb);
392 static inline void skb_truesize_check(struct sk_buff *skb)
394 int len = sizeof(struct sk_buff) + skb->len;
396 if (unlikely((int)skb->truesize < len))
397 skb_truesize_bug(skb);
400 extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
401 int getfrag(void *from, char *to, int offset,
402 int len,int odd, struct sk_buff *skb),
403 void *from, int length);
410 __u32 stepped_offset;
411 struct sk_buff *root_skb;
412 struct sk_buff *cur_skb;
416 extern void skb_prepare_seq_read(struct sk_buff *skb,
417 unsigned int from, unsigned int to,
418 struct skb_seq_state *st);
419 extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
420 struct skb_seq_state *st);
421 extern void skb_abort_seq_read(struct skb_seq_state *st);
423 extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
424 unsigned int to, struct ts_config *config,
425 struct ts_state *state);
427 #ifdef NET_SKBUFF_DATA_USES_OFFSET
428 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
430 return skb->head + skb->end;
433 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
440 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
443 * skb_queue_empty - check if a queue is empty
446 * Returns true if the queue is empty, false otherwise.
448 static inline int skb_queue_empty(const struct sk_buff_head *list)
450 return list->next == (struct sk_buff *)list;
454 * skb_get - reference buffer
455 * @skb: buffer to reference
457 * Makes another reference to a socket buffer and returns a pointer
460 static inline struct sk_buff *skb_get(struct sk_buff *skb)
462 atomic_inc(&skb->users);
467 * If users == 1, we are the only owner and are can avoid redundant
472 * skb_cloned - is the buffer a clone
473 * @skb: buffer to check
475 * Returns true if the buffer was generated with skb_clone() and is
476 * one of multiple shared copies of the buffer. Cloned buffers are
477 * shared data so must not be written to under normal circumstances.
479 static inline int skb_cloned(const struct sk_buff *skb)
481 return skb->cloned &&
482 (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
486 * skb_header_cloned - is the header a clone
487 * @skb: buffer to check
489 * Returns true if modifying the header part of the buffer requires
490 * the data to be copied.
492 static inline int skb_header_cloned(const struct sk_buff *skb)
499 dataref = atomic_read(&skb_shinfo(skb)->dataref);
500 dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
505 * skb_header_release - release reference to header
506 * @skb: buffer to operate on
508 * Drop a reference to the header part of the buffer. This is done
509 * by acquiring a payload reference. You must not read from the header
510 * part of skb->data after this.
512 static inline void skb_header_release(struct sk_buff *skb)
516 atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
520 * skb_shared - is the buffer shared
521 * @skb: buffer to check
523 * Returns true if more than one person has a reference to this
526 static inline int skb_shared(const struct sk_buff *skb)
528 return atomic_read(&skb->users) != 1;
532 * skb_share_check - check if buffer is shared and if so clone it
533 * @skb: buffer to check
534 * @pri: priority for memory allocation
536 * If the buffer is shared the buffer is cloned and the old copy
537 * drops a reference. A new clone with a single reference is returned.
538 * If the buffer is not shared the original buffer is returned. When
539 * being called from interrupt status or with spinlocks held pri must
542 * NULL is returned on a memory allocation failure.
544 static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
547 might_sleep_if(pri & __GFP_WAIT);
548 if (skb_shared(skb)) {
549 struct sk_buff *nskb = skb_clone(skb, pri);
557 * Copy shared buffers into a new sk_buff. We effectively do COW on
558 * packets to handle cases where we have a local reader and forward
559 * and a couple of other messy ones. The normal one is tcpdumping
560 * a packet thats being forwarded.
564 * skb_unshare - make a copy of a shared buffer
565 * @skb: buffer to check
566 * @pri: priority for memory allocation
568 * If the socket buffer is a clone then this function creates a new
569 * copy of the data, drops a reference count on the old copy and returns
570 * the new copy with the reference count at 1. If the buffer is not a clone
571 * the original buffer is returned. When called with a spinlock held or
572 * from interrupt state @pri must be %GFP_ATOMIC
574 * %NULL is returned on a memory allocation failure.
576 static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
579 might_sleep_if(pri & __GFP_WAIT);
580 if (skb_cloned(skb)) {
581 struct sk_buff *nskb = skb_copy(skb, pri);
582 kfree_skb(skb); /* Free our shared copy */
590 * @list_: list to peek at
592 * Peek an &sk_buff. Unlike most other operations you _MUST_
593 * be careful with this one. A peek leaves the buffer on the
594 * list and someone else may run off with it. You must hold
595 * the appropriate locks or have a private queue to do this.
597 * Returns %NULL for an empty list or a pointer to the head element.
598 * The reference count is not incremented and the reference is therefore
599 * volatile. Use with caution.
601 static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
603 struct sk_buff *list = ((struct sk_buff *)list_)->next;
604 if (list == (struct sk_buff *)list_)
611 * @list_: list to peek at
613 * Peek an &sk_buff. Unlike most other operations you _MUST_
614 * be careful with this one. A peek leaves the buffer on the
615 * list and someone else may run off with it. You must hold
616 * the appropriate locks or have a private queue to do this.
618 * Returns %NULL for an empty list or a pointer to the tail element.
619 * The reference count is not incremented and the reference is therefore
620 * volatile. Use with caution.
622 static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
624 struct sk_buff *list = ((struct sk_buff *)list_)->prev;
625 if (list == (struct sk_buff *)list_)
631 * skb_queue_len - get queue length
632 * @list_: list to measure
634 * Return the length of an &sk_buff queue.
636 static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
642 * This function creates a split out lock class for each invocation;
643 * this is needed for now since a whole lot of users of the skb-queue
644 * infrastructure in drivers have different locking usage (in hardirq)
645 * than the networking core (in softirq only). In the long run either the
646 * network layer or drivers should need annotation to consolidate the
647 * main types of usage into 3 classes.
649 static inline void skb_queue_head_init(struct sk_buff_head *list)
651 spin_lock_init(&list->lock);
652 list->prev = list->next = (struct sk_buff *)list;
656 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
657 struct lock_class_key *class)
659 skb_queue_head_init(list);
660 lockdep_set_class(&list->lock, class);
664 * Insert an sk_buff at the start of a list.
666 * The "__skb_xxxx()" functions are the non-atomic ones that
667 * can only be called with interrupts disabled.
671 * __skb_queue_after - queue a buffer at the list head
673 * @prev: place after this buffer
674 * @newsk: buffer to queue
676 * Queue a buffer int the middle of a list. This function takes no locks
677 * and you must therefore hold required locks before calling it.
679 * A buffer cannot be placed on two lists at the same time.
681 static inline void __skb_queue_after(struct sk_buff_head *list,
682 struct sk_buff *prev,
683 struct sk_buff *newsk)
685 struct sk_buff *next;
691 next->prev = prev->next = newsk;
695 * __skb_queue_head - queue a buffer at the list head
697 * @newsk: buffer to queue
699 * Queue a buffer at the start of a list. This function takes no locks
700 * and you must therefore hold required locks before calling it.
702 * A buffer cannot be placed on two lists at the same time.
704 extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
705 static inline void __skb_queue_head(struct sk_buff_head *list,
706 struct sk_buff *newsk)
708 __skb_queue_after(list, (struct sk_buff *)list, newsk);
712 * __skb_queue_tail - queue a buffer at the list tail
714 * @newsk: buffer to queue
716 * Queue a buffer at the end of a list. This function takes no locks
717 * and you must therefore hold required locks before calling it.
719 * A buffer cannot be placed on two lists at the same time.
721 extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
722 static inline void __skb_queue_tail(struct sk_buff_head *list,
723 struct sk_buff *newsk)
725 struct sk_buff *prev, *next;
728 next = (struct sk_buff *)list;
732 next->prev = prev->next = newsk;
737 * __skb_dequeue - remove from the head of the queue
738 * @list: list to dequeue from
740 * Remove the head of the list. This function does not take any locks
741 * so must be used with appropriate locks held only. The head item is
742 * returned or %NULL if the list is empty.
744 extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
745 static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
747 struct sk_buff *next, *prev, *result;
749 prev = (struct sk_buff *) list;
758 result->next = result->prev = NULL;
765 * Insert a packet on a list.
767 extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
768 static inline void __skb_insert(struct sk_buff *newsk,
769 struct sk_buff *prev, struct sk_buff *next,
770 struct sk_buff_head *list)
774 next->prev = prev->next = newsk;
779 * Place a packet after a given packet in a list.
781 extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
782 static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
784 __skb_insert(newsk, old, old->next, list);
788 * remove sk_buff from list. _Must_ be called atomically, and with
791 extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
792 static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
794 struct sk_buff *next, *prev;
799 skb->next = skb->prev = NULL;
805 /* XXX: more streamlined implementation */
808 * __skb_dequeue_tail - remove from the tail of the queue
809 * @list: list to dequeue from
811 * Remove the tail of the list. This function does not take any locks
812 * so must be used with appropriate locks held only. The tail item is
813 * returned or %NULL if the list is empty.
815 extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
816 static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
818 struct sk_buff *skb = skb_peek_tail(list);
820 __skb_unlink(skb, list);
825 static inline int skb_is_nonlinear(const struct sk_buff *skb)
827 return skb->data_len;
830 static inline unsigned int skb_headlen(const struct sk_buff *skb)
832 return skb->len - skb->data_len;
835 static inline int skb_pagelen(const struct sk_buff *skb)
839 for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
840 len += skb_shinfo(skb)->frags[i].size;
841 return len + skb_headlen(skb);
844 static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
845 struct page *page, int off, int size)
847 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
850 frag->page_offset = off;
852 skb_shinfo(skb)->nr_frags = i + 1;
855 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
856 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
857 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
859 #ifdef NET_SKBUFF_DATA_USES_OFFSET
860 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
862 return skb->head + skb->tail;
865 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
867 skb->tail = skb->data - skb->head;
870 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
872 skb_reset_tail_pointer(skb);
875 #else /* NET_SKBUFF_DATA_USES_OFFSET */
876 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
881 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
883 skb->tail = skb->data;
886 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
888 skb->tail = skb->data + offset;
891 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
894 * Add data to an sk_buff
896 extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
897 static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
899 unsigned char *tmp = skb_tail_pointer(skb);
900 SKB_LINEAR_ASSERT(skb);
906 extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len);
907 static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
914 extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);
915 static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
918 BUG_ON(skb->len < skb->data_len);
919 return skb->data += len;
922 extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
924 static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
926 if (len > skb_headlen(skb) &&
927 !__pskb_pull_tail(skb, len-skb_headlen(skb)))
930 return skb->data += len;
933 static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
935 return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
938 static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
940 if (likely(len <= skb_headlen(skb)))
942 if (unlikely(len > skb->len))
944 return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL;
948 * skb_headroom - bytes at buffer head
949 * @skb: buffer to check
951 * Return the number of bytes of free space at the head of an &sk_buff.
953 static inline unsigned int skb_headroom(const struct sk_buff *skb)
955 return skb->data - skb->head;
959 * skb_tailroom - bytes at buffer end
960 * @skb: buffer to check
962 * Return the number of bytes of free space at the tail of an sk_buff
964 static inline int skb_tailroom(const struct sk_buff *skb)
966 return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
970 * skb_reserve - adjust headroom
971 * @skb: buffer to alter
972 * @len: bytes to move
974 * Increase the headroom of an empty &sk_buff by reducing the tail
975 * room. This is only allowed for an empty buffer.
977 static inline void skb_reserve(struct sk_buff *skb, int len)
983 #ifdef NET_SKBUFF_DATA_USES_OFFSET
984 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
986 return skb->head + skb->transport_header;
989 static inline void skb_reset_transport_header(struct sk_buff *skb)
991 skb->transport_header = skb->data - skb->head;
994 static inline void skb_set_transport_header(struct sk_buff *skb,
997 skb_reset_transport_header(skb);
998 skb->transport_header += offset;
1001 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1003 return skb->head + skb->network_header;
1006 static inline void skb_reset_network_header(struct sk_buff *skb)
1008 skb->network_header = skb->data - skb->head;
1011 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1013 skb_reset_network_header(skb);
1014 skb->network_header += offset;
1017 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1019 return skb->head + skb->mac_header;
1022 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1024 return skb->mac_header != ~0U;
1027 static inline void skb_reset_mac_header(struct sk_buff *skb)
1029 skb->mac_header = skb->data - skb->head;
1032 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1034 skb_reset_mac_header(skb);
1035 skb->mac_header += offset;
1038 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1040 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
1042 return skb->transport_header;
1045 static inline void skb_reset_transport_header(struct sk_buff *skb)
1047 skb->transport_header = skb->data;
1050 static inline void skb_set_transport_header(struct sk_buff *skb,
1053 skb->transport_header = skb->data + offset;
1056 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1058 return skb->network_header;
1061 static inline void skb_reset_network_header(struct sk_buff *skb)
1063 skb->network_header = skb->data;
1066 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1068 skb->network_header = skb->data + offset;
1071 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1073 return skb->mac_header;
1076 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1078 return skb->mac_header != NULL;
1081 static inline void skb_reset_mac_header(struct sk_buff *skb)
1083 skb->mac_header = skb->data;
1086 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1088 skb->mac_header = skb->data + offset;
1090 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1092 static inline int skb_transport_offset(const struct sk_buff *skb)
1094 return skb_transport_header(skb) - skb->data;
1097 static inline u32 skb_network_header_len(const struct sk_buff *skb)
1099 return skb->transport_header - skb->network_header;
1102 static inline int skb_network_offset(const struct sk_buff *skb)
1104 return skb_network_header(skb) - skb->data;
1108 * CPUs often take a performance hit when accessing unaligned memory
1109 * locations. The actual performance hit varies, it can be small if the
1110 * hardware handles it or large if we have to take an exception and fix it
1113 * Since an ethernet header is 14 bytes network drivers often end up with
1114 * the IP header at an unaligned offset. The IP header can be aligned by
1115 * shifting the start of the packet by 2 bytes. Drivers should do this
1118 * skb_reserve(NET_IP_ALIGN);
1120 * The downside to this alignment of the IP header is that the DMA is now
1121 * unaligned. On some architectures the cost of an unaligned DMA is high
1122 * and this cost outweighs the gains made by aligning the IP header.
1124 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1127 #ifndef NET_IP_ALIGN
1128 #define NET_IP_ALIGN 2
1132 * The networking layer reserves some headroom in skb data (via
1133 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1134 * the header has to grow. In the default case, if the header has to grow
1135 * 16 bytes or less we avoid the reallocation.
1137 * Unfortunately this headroom changes the DMA alignment of the resulting
1138 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1139 * on some architectures. An architecture can override this value,
1140 * perhaps setting it to a cacheline in size (since that will maintain
1141 * cacheline alignment of the DMA). It must be a power of 2.
1143 * Various parts of the networking layer expect at least 16 bytes of
1144 * headroom, you should not reduce this.
1147 #define NET_SKB_PAD 16
1150 extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
1152 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
1154 if (unlikely(skb->data_len)) {
1159 skb_set_tail_pointer(skb, len);
1162 extern void skb_trim(struct sk_buff *skb, unsigned int len);
1164 static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
1167 return ___pskb_trim(skb, len);
1168 __skb_trim(skb, len);
1172 static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
1174 return (len < skb->len) ? __pskb_trim(skb, len) : 0;
1178 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1179 * @skb: buffer to alter
1182 * This is identical to pskb_trim except that the caller knows that
1183 * the skb is not cloned so we should never get an error due to out-
1186 static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
1188 int err = pskb_trim(skb, len);
1193 * skb_orphan - orphan a buffer
1194 * @skb: buffer to orphan
1196 * If a buffer currently has an owner then we call the owner's
1197 * destructor function and make the @skb unowned. The buffer continues
1198 * to exist but is no longer charged to its former owner.
1200 static inline void skb_orphan(struct sk_buff *skb)
1202 if (skb->destructor)
1203 skb->destructor(skb);
1204 skb->destructor = NULL;
1209 * __skb_queue_purge - empty a list
1210 * @list: list to empty
1212 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1213 * the list and one reference dropped. This function does not take the
1214 * list lock and the caller must hold the relevant locks to use it.
1216 extern void skb_queue_purge(struct sk_buff_head *list);
1217 static inline void __skb_queue_purge(struct sk_buff_head *list)
1219 struct sk_buff *skb;
1220 while ((skb = __skb_dequeue(list)) != NULL)
1225 * __dev_alloc_skb - allocate an skbuff for receiving
1226 * @length: length to allocate
1227 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1229 * Allocate a new &sk_buff and assign it a usage count of one. The
1230 * buffer has unspecified headroom built in. Users should allocate
1231 * the headroom they think they need without accounting for the
1232 * built in space. The built in space is used for optimisations.
1234 * %NULL is returned if there is no free memory.
1236 static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
1239 struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
1241 skb_reserve(skb, NET_SKB_PAD);
1245 extern struct sk_buff *dev_alloc_skb(unsigned int length);
1247 extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
1248 unsigned int length, gfp_t gfp_mask);
1251 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1252 * @dev: network device to receive on
1253 * @length: length to allocate
1255 * Allocate a new &sk_buff and assign it a usage count of one. The
1256 * buffer has unspecified headroom built in. Users should allocate
1257 * the headroom they think they need without accounting for the
1258 * built in space. The built in space is used for optimisations.
1260 * %NULL is returned if there is no free memory. Although this function
1261 * allocates memory it can be called from an interrupt.
1263 static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
1264 unsigned int length)
1266 return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
1270 * skb_clone_writable - is the header of a clone writable
1271 * @skb: buffer to check
1272 * @len: length up to which to write
1274 * Returns true if modifying the header part of the cloned buffer
1275 * does not requires the data to be copied.
1277 static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len)
1279 return !skb_header_cloned(skb) &&
1280 skb_headroom(skb) + len <= skb->hdr_len;
1283 static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
1288 if (headroom < NET_SKB_PAD)
1289 headroom = NET_SKB_PAD;
1290 if (headroom > skb_headroom(skb))
1291 delta = headroom - skb_headroom(skb);
1293 if (delta || cloned)
1294 return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
1300 * skb_cow - copy header of skb when it is required
1301 * @skb: buffer to cow
1302 * @headroom: needed headroom
1304 * If the skb passed lacks sufficient headroom or its data part
1305 * is shared, data is reallocated. If reallocation fails, an error
1306 * is returned and original skb is not changed.
1308 * The result is skb with writable area skb->head...skb->tail
1309 * and at least @headroom of space at head.
1311 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
1313 return __skb_cow(skb, headroom, skb_cloned(skb));
1317 * skb_cow_head - skb_cow but only making the head writable
1318 * @skb: buffer to cow
1319 * @headroom: needed headroom
1321 * This function is identical to skb_cow except that we replace the
1322 * skb_cloned check by skb_header_cloned. It should be used when
1323 * you only need to push on some header and do not need to modify
1326 static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
1328 return __skb_cow(skb, headroom, skb_header_cloned(skb));
1332 * skb_padto - pad an skbuff up to a minimal size
1333 * @skb: buffer to pad
1334 * @len: minimal length
1336 * Pads up a buffer to ensure the trailing bytes exist and are
1337 * blanked. If the buffer already contains sufficient data it
1338 * is untouched. Otherwise it is extended. Returns zero on
1339 * success. The skb is freed on error.
1342 static inline int skb_padto(struct sk_buff *skb, unsigned int len)
1344 unsigned int size = skb->len;
1345 if (likely(size >= len))
1347 return skb_pad(skb, len-size);
1350 static inline int skb_add_data(struct sk_buff *skb,
1351 char __user *from, int copy)
1353 const int off = skb->len;
1355 if (skb->ip_summed == CHECKSUM_NONE) {
1357 __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
1360 skb->csum = csum_block_add(skb->csum, csum, off);
1363 } else if (!copy_from_user(skb_put(skb, copy), from, copy))
1366 __skb_trim(skb, off);
1370 static inline int skb_can_coalesce(struct sk_buff *skb, int i,
1371 struct page *page, int off)
1374 struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
1376 return page == frag->page &&
1377 off == frag->page_offset + frag->size;
1382 static inline int __skb_linearize(struct sk_buff *skb)
1384 return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
1388 * skb_linearize - convert paged skb to linear one
1389 * @skb: buffer to linarize
1391 * If there is no free memory -ENOMEM is returned, otherwise zero
1392 * is returned and the old skb data released.
1394 static inline int skb_linearize(struct sk_buff *skb)
1396 return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
1400 * skb_linearize_cow - make sure skb is linear and writable
1401 * @skb: buffer to process
1403 * If there is no free memory -ENOMEM is returned, otherwise zero
1404 * is returned and the old skb data released.
1406 static inline int skb_linearize_cow(struct sk_buff *skb)
1408 return skb_is_nonlinear(skb) || skb_cloned(skb) ?
1409 __skb_linearize(skb) : 0;
1413 * skb_postpull_rcsum - update checksum for received skb after pull
1414 * @skb: buffer to update
1415 * @start: start of data before pull
1416 * @len: length of data pulled
1418 * After doing a pull on a received packet, you need to call this to
1419 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
1420 * CHECKSUM_NONE so that it can be recomputed from scratch.
1423 static inline void skb_postpull_rcsum(struct sk_buff *skb,
1424 const void *start, unsigned int len)
1426 if (skb->ip_summed == CHECKSUM_COMPLETE)
1427 skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
1430 unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
1433 * pskb_trim_rcsum - trim received skb and update checksum
1434 * @skb: buffer to trim
1437 * This is exactly the same as pskb_trim except that it ensures the
1438 * checksum of received packets are still valid after the operation.
1441 static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
1443 if (likely(len >= skb->len))
1445 if (skb->ip_summed == CHECKSUM_COMPLETE)
1446 skb->ip_summed = CHECKSUM_NONE;
1447 return __pskb_trim(skb, len);
1450 #define skb_queue_walk(queue, skb) \
1451 for (skb = (queue)->next; \
1452 prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
1455 #define skb_queue_walk_safe(queue, skb, tmp) \
1456 for (skb = (queue)->next, tmp = skb->next; \
1457 skb != (struct sk_buff *)(queue); \
1458 skb = tmp, tmp = skb->next)
1460 #define skb_queue_reverse_walk(queue, skb) \
1461 for (skb = (queue)->prev; \
1462 prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
1466 extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
1467 int *peeked, int *err);
1468 extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
1469 int noblock, int *err);
1470 extern unsigned int datagram_poll(struct file *file, struct socket *sock,
1471 struct poll_table_struct *wait);
1472 extern int skb_copy_datagram_iovec(const struct sk_buff *from,
1473 int offset, struct iovec *to,
1475 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
1478 extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
1479 extern int skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
1480 unsigned int flags);
1481 extern __wsum skb_checksum(const struct sk_buff *skb, int offset,
1482 int len, __wsum csum);
1483 extern int skb_copy_bits(const struct sk_buff *skb, int offset,
1485 extern int skb_store_bits(struct sk_buff *skb, int offset,
1486 const void *from, int len);
1487 extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb,
1488 int offset, u8 *to, int len,
1490 extern int skb_splice_bits(struct sk_buff *skb,
1491 unsigned int offset,
1492 struct pipe_inode_info *pipe,
1494 unsigned int flags);
1495 extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
1496 extern void skb_split(struct sk_buff *skb,
1497 struct sk_buff *skb1, const u32 len);
1499 extern struct sk_buff *skb_segment(struct sk_buff *skb, int features);
1501 static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
1502 int len, void *buffer)
1504 int hlen = skb_headlen(skb);
1506 if (hlen - offset >= len)
1507 return skb->data + offset;
1509 if (skb_copy_bits(skb, offset, buffer, len) < 0)
1515 static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
1517 const unsigned int len)
1519 memcpy(to, skb->data, len);
1522 static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
1523 const int offset, void *to,
1524 const unsigned int len)
1526 memcpy(to, skb->data + offset, len);
1529 static inline void skb_copy_to_linear_data(struct sk_buff *skb,
1531 const unsigned int len)
1533 memcpy(skb->data, from, len);
1536 static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
1539 const unsigned int len)
1541 memcpy(skb->data + offset, from, len);
1544 extern void skb_init(void);
1547 * skb_get_timestamp - get timestamp from a skb
1548 * @skb: skb to get stamp from
1549 * @stamp: pointer to struct timeval to store stamp in
1551 * Timestamps are stored in the skb as offsets to a base timestamp.
1552 * This function converts the offset back to a struct timeval and stores
1555 static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
1557 *stamp = ktime_to_timeval(skb->tstamp);
1560 static inline void __net_timestamp(struct sk_buff *skb)
1562 skb->tstamp = ktime_get_real();
1565 static inline ktime_t net_timedelta(ktime_t t)
1567 return ktime_sub(ktime_get_real(), t);
1570 static inline ktime_t net_invalid_timestamp(void)
1572 return ktime_set(0, 0);
1575 extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
1576 extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
1578 static inline int skb_csum_unnecessary(const struct sk_buff *skb)
1580 return skb->ip_summed & CHECKSUM_UNNECESSARY;
1584 * skb_checksum_complete - Calculate checksum of an entire packet
1585 * @skb: packet to process
1587 * This function calculates the checksum over the entire packet plus
1588 * the value of skb->csum. The latter can be used to supply the
1589 * checksum of a pseudo header as used by TCP/UDP. It returns the
1592 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
1593 * this function can be used to verify that checksum on received
1594 * packets. In that case the function should return zero if the
1595 * checksum is correct. In particular, this function will return zero
1596 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
1597 * hardware has already verified the correctness of the checksum.
1599 static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
1601 return skb_csum_unnecessary(skb) ?
1602 0 : __skb_checksum_complete(skb);
1605 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1606 extern void nf_conntrack_destroy(struct nf_conntrack *nfct);
1607 static inline void nf_conntrack_put(struct nf_conntrack *nfct)
1609 if (nfct && atomic_dec_and_test(&nfct->use))
1610 nf_conntrack_destroy(nfct);
1612 static inline void nf_conntrack_get(struct nf_conntrack *nfct)
1615 atomic_inc(&nfct->use);
1617 static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
1620 atomic_inc(&skb->users);
1622 static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
1628 #ifdef CONFIG_BRIDGE_NETFILTER
1629 static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
1631 if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
1634 static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
1637 atomic_inc(&nf_bridge->use);
1639 #endif /* CONFIG_BRIDGE_NETFILTER */
1640 static inline void nf_reset(struct sk_buff *skb)
1642 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1643 nf_conntrack_put(skb->nfct);
1645 nf_conntrack_put_reasm(skb->nfct_reasm);
1646 skb->nfct_reasm = NULL;
1648 #ifdef CONFIG_BRIDGE_NETFILTER
1649 nf_bridge_put(skb->nf_bridge);
1650 skb->nf_bridge = NULL;
1654 /* Note: This doesn't put any conntrack and bridge info in dst. */
1655 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1657 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1658 dst->nfct = src->nfct;
1659 nf_conntrack_get(src->nfct);
1660 dst->nfctinfo = src->nfctinfo;
1661 dst->nfct_reasm = src->nfct_reasm;
1662 nf_conntrack_get_reasm(src->nfct_reasm);
1664 #ifdef CONFIG_BRIDGE_NETFILTER
1665 dst->nf_bridge = src->nf_bridge;
1666 nf_bridge_get(src->nf_bridge);
1670 static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1672 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1673 nf_conntrack_put(dst->nfct);
1674 nf_conntrack_put_reasm(dst->nfct_reasm);
1676 #ifdef CONFIG_BRIDGE_NETFILTER
1677 nf_bridge_put(dst->nf_bridge);
1679 __nf_copy(dst, src);
1682 #ifdef CONFIG_NETWORK_SECMARK
1683 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1685 to->secmark = from->secmark;
1688 static inline void skb_init_secmark(struct sk_buff *skb)
1693 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1696 static inline void skb_init_secmark(struct sk_buff *skb)
1700 static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
1702 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1703 skb->queue_mapping = queue_mapping;
1707 static inline u16 skb_get_queue_mapping(struct sk_buff *skb)
1709 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1710 return skb->queue_mapping;
1716 static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
1718 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1719 to->queue_mapping = from->queue_mapping;
1723 static inline int skb_is_gso(const struct sk_buff *skb)
1725 return skb_shinfo(skb)->gso_size;
1728 static inline int skb_is_gso_v6(const struct sk_buff *skb)
1730 return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
1733 static inline void skb_forward_csum(struct sk_buff *skb)
1735 /* Unfortunately we don't support this one. Any brave souls? */
1736 if (skb->ip_summed == CHECKSUM_COMPLETE)
1737 skb->ip_summed = CHECKSUM_NONE;
1740 bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
1741 #endif /* __KERNEL__ */
1742 #endif /* _LINUX_SKBUFF_H */