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 #ifdef CONFIG_IPV6_NDISC_NODETYPE
317 __u8 ndisc_nodetype:2;
321 #ifdef CONFIG_NET_DMA
322 dma_cookie_t dma_cookie;
324 #ifdef CONFIG_NETWORK_SECMARK
330 sk_buff_data_t transport_header;
331 sk_buff_data_t network_header;
332 sk_buff_data_t mac_header;
333 /* These elements must be at the end, see alloc_skb() for details. */
338 unsigned int truesize;
344 * Handling routines are only of interest to the kernel
346 #include <linux/slab.h>
348 #include <asm/system.h>
350 extern void kfree_skb(struct sk_buff *skb);
351 extern void __kfree_skb(struct sk_buff *skb);
352 extern struct sk_buff *__alloc_skb(unsigned int size,
353 gfp_t priority, int fclone, int node);
354 static inline struct sk_buff *alloc_skb(unsigned int size,
357 return __alloc_skb(size, priority, 0, -1);
360 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
363 return __alloc_skb(size, priority, 1, -1);
366 extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
367 extern struct sk_buff *skb_clone(struct sk_buff *skb,
369 extern struct sk_buff *skb_copy(const struct sk_buff *skb,
371 extern struct sk_buff *pskb_copy(struct sk_buff *skb,
373 extern int pskb_expand_head(struct sk_buff *skb,
374 int nhead, int ntail,
376 extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
377 unsigned int headroom);
378 extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
379 int newheadroom, int newtailroom,
381 extern int skb_to_sgvec(struct sk_buff *skb,
382 struct scatterlist *sg, int offset,
384 extern int skb_cow_data(struct sk_buff *skb, int tailbits,
385 struct sk_buff **trailer);
386 extern int skb_pad(struct sk_buff *skb, int pad);
387 #define dev_kfree_skb(a) kfree_skb(a)
388 extern void skb_over_panic(struct sk_buff *skb, int len,
390 extern void skb_under_panic(struct sk_buff *skb, int len,
392 extern void skb_truesize_bug(struct sk_buff *skb);
394 static inline void skb_truesize_check(struct sk_buff *skb)
396 int len = sizeof(struct sk_buff) + skb->len;
398 if (unlikely((int)skb->truesize < len))
399 skb_truesize_bug(skb);
402 extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
403 int getfrag(void *from, char *to, int offset,
404 int len,int odd, struct sk_buff *skb),
405 void *from, int length);
412 __u32 stepped_offset;
413 struct sk_buff *root_skb;
414 struct sk_buff *cur_skb;
418 extern void skb_prepare_seq_read(struct sk_buff *skb,
419 unsigned int from, unsigned int to,
420 struct skb_seq_state *st);
421 extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
422 struct skb_seq_state *st);
423 extern void skb_abort_seq_read(struct skb_seq_state *st);
425 extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
426 unsigned int to, struct ts_config *config,
427 struct ts_state *state);
429 #ifdef NET_SKBUFF_DATA_USES_OFFSET
430 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
432 return skb->head + skb->end;
435 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
442 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
445 * skb_queue_empty - check if a queue is empty
448 * Returns true if the queue is empty, false otherwise.
450 static inline int skb_queue_empty(const struct sk_buff_head *list)
452 return list->next == (struct sk_buff *)list;
456 * skb_get - reference buffer
457 * @skb: buffer to reference
459 * Makes another reference to a socket buffer and returns a pointer
462 static inline struct sk_buff *skb_get(struct sk_buff *skb)
464 atomic_inc(&skb->users);
469 * If users == 1, we are the only owner and are can avoid redundant
474 * skb_cloned - is the buffer a clone
475 * @skb: buffer to check
477 * Returns true if the buffer was generated with skb_clone() and is
478 * one of multiple shared copies of the buffer. Cloned buffers are
479 * shared data so must not be written to under normal circumstances.
481 static inline int skb_cloned(const struct sk_buff *skb)
483 return skb->cloned &&
484 (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
488 * skb_header_cloned - is the header a clone
489 * @skb: buffer to check
491 * Returns true if modifying the header part of the buffer requires
492 * the data to be copied.
494 static inline int skb_header_cloned(const struct sk_buff *skb)
501 dataref = atomic_read(&skb_shinfo(skb)->dataref);
502 dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
507 * skb_header_release - release reference to header
508 * @skb: buffer to operate on
510 * Drop a reference to the header part of the buffer. This is done
511 * by acquiring a payload reference. You must not read from the header
512 * part of skb->data after this.
514 static inline void skb_header_release(struct sk_buff *skb)
518 atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
522 * skb_shared - is the buffer shared
523 * @skb: buffer to check
525 * Returns true if more than one person has a reference to this
528 static inline int skb_shared(const struct sk_buff *skb)
530 return atomic_read(&skb->users) != 1;
534 * skb_share_check - check if buffer is shared and if so clone it
535 * @skb: buffer to check
536 * @pri: priority for memory allocation
538 * If the buffer is shared the buffer is cloned and the old copy
539 * drops a reference. A new clone with a single reference is returned.
540 * If the buffer is not shared the original buffer is returned. When
541 * being called from interrupt status or with spinlocks held pri must
544 * NULL is returned on a memory allocation failure.
546 static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
549 might_sleep_if(pri & __GFP_WAIT);
550 if (skb_shared(skb)) {
551 struct sk_buff *nskb = skb_clone(skb, pri);
559 * Copy shared buffers into a new sk_buff. We effectively do COW on
560 * packets to handle cases where we have a local reader and forward
561 * and a couple of other messy ones. The normal one is tcpdumping
562 * a packet thats being forwarded.
566 * skb_unshare - make a copy of a shared buffer
567 * @skb: buffer to check
568 * @pri: priority for memory allocation
570 * If the socket buffer is a clone then this function creates a new
571 * copy of the data, drops a reference count on the old copy and returns
572 * the new copy with the reference count at 1. If the buffer is not a clone
573 * the original buffer is returned. When called with a spinlock held or
574 * from interrupt state @pri must be %GFP_ATOMIC
576 * %NULL is returned on a memory allocation failure.
578 static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
581 might_sleep_if(pri & __GFP_WAIT);
582 if (skb_cloned(skb)) {
583 struct sk_buff *nskb = skb_copy(skb, pri);
584 kfree_skb(skb); /* Free our shared copy */
592 * @list_: list to peek at
594 * Peek an &sk_buff. Unlike most other operations you _MUST_
595 * be careful with this one. A peek leaves the buffer on the
596 * list and someone else may run off with it. You must hold
597 * the appropriate locks or have a private queue to do this.
599 * Returns %NULL for an empty list or a pointer to the head element.
600 * The reference count is not incremented and the reference is therefore
601 * volatile. Use with caution.
603 static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
605 struct sk_buff *list = ((struct sk_buff *)list_)->next;
606 if (list == (struct sk_buff *)list_)
613 * @list_: list to peek at
615 * Peek an &sk_buff. Unlike most other operations you _MUST_
616 * be careful with this one. A peek leaves the buffer on the
617 * list and someone else may run off with it. You must hold
618 * the appropriate locks or have a private queue to do this.
620 * Returns %NULL for an empty list or a pointer to the tail element.
621 * The reference count is not incremented and the reference is therefore
622 * volatile. Use with caution.
624 static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
626 struct sk_buff *list = ((struct sk_buff *)list_)->prev;
627 if (list == (struct sk_buff *)list_)
633 * skb_queue_len - get queue length
634 * @list_: list to measure
636 * Return the length of an &sk_buff queue.
638 static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
644 * This function creates a split out lock class for each invocation;
645 * this is needed for now since a whole lot of users of the skb-queue
646 * infrastructure in drivers have different locking usage (in hardirq)
647 * than the networking core (in softirq only). In the long run either the
648 * network layer or drivers should need annotation to consolidate the
649 * main types of usage into 3 classes.
651 static inline void skb_queue_head_init(struct sk_buff_head *list)
653 spin_lock_init(&list->lock);
654 list->prev = list->next = (struct sk_buff *)list;
658 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
659 struct lock_class_key *class)
661 skb_queue_head_init(list);
662 lockdep_set_class(&list->lock, class);
666 * Insert an sk_buff at the start of a list.
668 * The "__skb_xxxx()" functions are the non-atomic ones that
669 * can only be called with interrupts disabled.
673 * __skb_queue_after - queue a buffer at the list head
675 * @prev: place after this buffer
676 * @newsk: buffer to queue
678 * Queue a buffer int the middle of a list. This function takes no locks
679 * and you must therefore hold required locks before calling it.
681 * A buffer cannot be placed on two lists at the same time.
683 static inline void __skb_queue_after(struct sk_buff_head *list,
684 struct sk_buff *prev,
685 struct sk_buff *newsk)
687 struct sk_buff *next;
693 next->prev = prev->next = newsk;
697 * __skb_queue_head - queue a buffer at the list head
699 * @newsk: buffer to queue
701 * Queue a buffer at the start of a list. This function takes no locks
702 * and you must therefore hold required locks before calling it.
704 * A buffer cannot be placed on two lists at the same time.
706 extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
707 static inline void __skb_queue_head(struct sk_buff_head *list,
708 struct sk_buff *newsk)
710 __skb_queue_after(list, (struct sk_buff *)list, newsk);
714 * __skb_queue_tail - queue a buffer at the list tail
716 * @newsk: buffer to queue
718 * Queue a buffer at the end of a list. This function takes no locks
719 * and you must therefore hold required locks before calling it.
721 * A buffer cannot be placed on two lists at the same time.
723 extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
724 static inline void __skb_queue_tail(struct sk_buff_head *list,
725 struct sk_buff *newsk)
727 struct sk_buff *prev, *next;
730 next = (struct sk_buff *)list;
734 next->prev = prev->next = newsk;
739 * __skb_dequeue - remove from the head of the queue
740 * @list: list to dequeue from
742 * Remove the head of the list. This function does not take any locks
743 * so must be used with appropriate locks held only. The head item is
744 * returned or %NULL if the list is empty.
746 extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
747 static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
749 struct sk_buff *next, *prev, *result;
751 prev = (struct sk_buff *) list;
760 result->next = result->prev = NULL;
767 * Insert a packet on a list.
769 extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
770 static inline void __skb_insert(struct sk_buff *newsk,
771 struct sk_buff *prev, struct sk_buff *next,
772 struct sk_buff_head *list)
776 next->prev = prev->next = newsk;
781 * Place a packet after a given packet in a list.
783 extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
784 static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
786 __skb_insert(newsk, old, old->next, list);
790 * remove sk_buff from list. _Must_ be called atomically, and with
793 extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
794 static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
796 struct sk_buff *next, *prev;
801 skb->next = skb->prev = NULL;
807 /* XXX: more streamlined implementation */
810 * __skb_dequeue_tail - remove from the tail of the queue
811 * @list: list to dequeue from
813 * Remove the tail of the list. This function does not take any locks
814 * so must be used with appropriate locks held only. The tail item is
815 * returned or %NULL if the list is empty.
817 extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
818 static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
820 struct sk_buff *skb = skb_peek_tail(list);
822 __skb_unlink(skb, list);
827 static inline int skb_is_nonlinear(const struct sk_buff *skb)
829 return skb->data_len;
832 static inline unsigned int skb_headlen(const struct sk_buff *skb)
834 return skb->len - skb->data_len;
837 static inline int skb_pagelen(const struct sk_buff *skb)
841 for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
842 len += skb_shinfo(skb)->frags[i].size;
843 return len + skb_headlen(skb);
846 static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
847 struct page *page, int off, int size)
849 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
852 frag->page_offset = off;
854 skb_shinfo(skb)->nr_frags = i + 1;
857 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
858 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
859 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
861 #ifdef NET_SKBUFF_DATA_USES_OFFSET
862 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
864 return skb->head + skb->tail;
867 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
869 skb->tail = skb->data - skb->head;
872 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
874 skb_reset_tail_pointer(skb);
877 #else /* NET_SKBUFF_DATA_USES_OFFSET */
878 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
883 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
885 skb->tail = skb->data;
888 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
890 skb->tail = skb->data + offset;
893 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
896 * Add data to an sk_buff
898 extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
899 static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
901 unsigned char *tmp = skb_tail_pointer(skb);
902 SKB_LINEAR_ASSERT(skb);
908 extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len);
909 static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
916 extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);
917 static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
920 BUG_ON(skb->len < skb->data_len);
921 return skb->data += len;
924 extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
926 static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
928 if (len > skb_headlen(skb) &&
929 !__pskb_pull_tail(skb, len-skb_headlen(skb)))
932 return skb->data += len;
935 static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
937 return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
940 static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
942 if (likely(len <= skb_headlen(skb)))
944 if (unlikely(len > skb->len))
946 return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL;
950 * skb_headroom - bytes at buffer head
951 * @skb: buffer to check
953 * Return the number of bytes of free space at the head of an &sk_buff.
955 static inline unsigned int skb_headroom(const struct sk_buff *skb)
957 return skb->data - skb->head;
961 * skb_tailroom - bytes at buffer end
962 * @skb: buffer to check
964 * Return the number of bytes of free space at the tail of an sk_buff
966 static inline int skb_tailroom(const struct sk_buff *skb)
968 return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
972 * skb_reserve - adjust headroom
973 * @skb: buffer to alter
974 * @len: bytes to move
976 * Increase the headroom of an empty &sk_buff by reducing the tail
977 * room. This is only allowed for an empty buffer.
979 static inline void skb_reserve(struct sk_buff *skb, int len)
985 #ifdef NET_SKBUFF_DATA_USES_OFFSET
986 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
988 return skb->head + skb->transport_header;
991 static inline void skb_reset_transport_header(struct sk_buff *skb)
993 skb->transport_header = skb->data - skb->head;
996 static inline void skb_set_transport_header(struct sk_buff *skb,
999 skb_reset_transport_header(skb);
1000 skb->transport_header += offset;
1003 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1005 return skb->head + skb->network_header;
1008 static inline void skb_reset_network_header(struct sk_buff *skb)
1010 skb->network_header = skb->data - skb->head;
1013 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1015 skb_reset_network_header(skb);
1016 skb->network_header += offset;
1019 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1021 return skb->head + skb->mac_header;
1024 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1026 return skb->mac_header != ~0U;
1029 static inline void skb_reset_mac_header(struct sk_buff *skb)
1031 skb->mac_header = skb->data - skb->head;
1034 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1036 skb_reset_mac_header(skb);
1037 skb->mac_header += offset;
1040 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1042 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
1044 return skb->transport_header;
1047 static inline void skb_reset_transport_header(struct sk_buff *skb)
1049 skb->transport_header = skb->data;
1052 static inline void skb_set_transport_header(struct sk_buff *skb,
1055 skb->transport_header = skb->data + offset;
1058 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1060 return skb->network_header;
1063 static inline void skb_reset_network_header(struct sk_buff *skb)
1065 skb->network_header = skb->data;
1068 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1070 skb->network_header = skb->data + offset;
1073 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1075 return skb->mac_header;
1078 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1080 return skb->mac_header != NULL;
1083 static inline void skb_reset_mac_header(struct sk_buff *skb)
1085 skb->mac_header = skb->data;
1088 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1090 skb->mac_header = skb->data + offset;
1092 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1094 static inline int skb_transport_offset(const struct sk_buff *skb)
1096 return skb_transport_header(skb) - skb->data;
1099 static inline u32 skb_network_header_len(const struct sk_buff *skb)
1101 return skb->transport_header - skb->network_header;
1104 static inline int skb_network_offset(const struct sk_buff *skb)
1106 return skb_network_header(skb) - skb->data;
1110 * CPUs often take a performance hit when accessing unaligned memory
1111 * locations. The actual performance hit varies, it can be small if the
1112 * hardware handles it or large if we have to take an exception and fix it
1115 * Since an ethernet header is 14 bytes network drivers often end up with
1116 * the IP header at an unaligned offset. The IP header can be aligned by
1117 * shifting the start of the packet by 2 bytes. Drivers should do this
1120 * skb_reserve(NET_IP_ALIGN);
1122 * The downside to this alignment of the IP header is that the DMA is now
1123 * unaligned. On some architectures the cost of an unaligned DMA is high
1124 * and this cost outweighs the gains made by aligning the IP header.
1126 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1129 #ifndef NET_IP_ALIGN
1130 #define NET_IP_ALIGN 2
1134 * The networking layer reserves some headroom in skb data (via
1135 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1136 * the header has to grow. In the default case, if the header has to grow
1137 * 16 bytes or less we avoid the reallocation.
1139 * Unfortunately this headroom changes the DMA alignment of the resulting
1140 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1141 * on some architectures. An architecture can override this value,
1142 * perhaps setting it to a cacheline in size (since that will maintain
1143 * cacheline alignment of the DMA). It must be a power of 2.
1145 * Various parts of the networking layer expect at least 16 bytes of
1146 * headroom, you should not reduce this.
1149 #define NET_SKB_PAD 16
1152 extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
1154 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
1156 if (unlikely(skb->data_len)) {
1161 skb_set_tail_pointer(skb, len);
1164 extern void skb_trim(struct sk_buff *skb, unsigned int len);
1166 static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
1169 return ___pskb_trim(skb, len);
1170 __skb_trim(skb, len);
1174 static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
1176 return (len < skb->len) ? __pskb_trim(skb, len) : 0;
1180 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1181 * @skb: buffer to alter
1184 * This is identical to pskb_trim except that the caller knows that
1185 * the skb is not cloned so we should never get an error due to out-
1188 static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
1190 int err = pskb_trim(skb, len);
1195 * skb_orphan - orphan a buffer
1196 * @skb: buffer to orphan
1198 * If a buffer currently has an owner then we call the owner's
1199 * destructor function and make the @skb unowned. The buffer continues
1200 * to exist but is no longer charged to its former owner.
1202 static inline void skb_orphan(struct sk_buff *skb)
1204 if (skb->destructor)
1205 skb->destructor(skb);
1206 skb->destructor = NULL;
1211 * __skb_queue_purge - empty a list
1212 * @list: list to empty
1214 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1215 * the list and one reference dropped. This function does not take the
1216 * list lock and the caller must hold the relevant locks to use it.
1218 extern void skb_queue_purge(struct sk_buff_head *list);
1219 static inline void __skb_queue_purge(struct sk_buff_head *list)
1221 struct sk_buff *skb;
1222 while ((skb = __skb_dequeue(list)) != NULL)
1227 * __dev_alloc_skb - allocate an skbuff for receiving
1228 * @length: length to allocate
1229 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1231 * Allocate a new &sk_buff and assign it a usage count of one. The
1232 * buffer has unspecified headroom built in. Users should allocate
1233 * the headroom they think they need without accounting for the
1234 * built in space. The built in space is used for optimisations.
1236 * %NULL is returned if there is no free memory.
1238 static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
1241 struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
1243 skb_reserve(skb, NET_SKB_PAD);
1247 extern struct sk_buff *dev_alloc_skb(unsigned int length);
1249 extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
1250 unsigned int length, gfp_t gfp_mask);
1253 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1254 * @dev: network device to receive on
1255 * @length: length to allocate
1257 * Allocate a new &sk_buff and assign it a usage count of one. The
1258 * buffer has unspecified headroom built in. Users should allocate
1259 * the headroom they think they need without accounting for the
1260 * built in space. The built in space is used for optimisations.
1262 * %NULL is returned if there is no free memory. Although this function
1263 * allocates memory it can be called from an interrupt.
1265 static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
1266 unsigned int length)
1268 return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
1272 * skb_clone_writable - is the header of a clone writable
1273 * @skb: buffer to check
1274 * @len: length up to which to write
1276 * Returns true if modifying the header part of the cloned buffer
1277 * does not requires the data to be copied.
1279 static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len)
1281 return !skb_header_cloned(skb) &&
1282 skb_headroom(skb) + len <= skb->hdr_len;
1285 static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
1290 if (headroom < NET_SKB_PAD)
1291 headroom = NET_SKB_PAD;
1292 if (headroom > skb_headroom(skb))
1293 delta = headroom - skb_headroom(skb);
1295 if (delta || cloned)
1296 return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
1302 * skb_cow - copy header of skb when it is required
1303 * @skb: buffer to cow
1304 * @headroom: needed headroom
1306 * If the skb passed lacks sufficient headroom or its data part
1307 * is shared, data is reallocated. If reallocation fails, an error
1308 * is returned and original skb is not changed.
1310 * The result is skb with writable area skb->head...skb->tail
1311 * and at least @headroom of space at head.
1313 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
1315 return __skb_cow(skb, headroom, skb_cloned(skb));
1319 * skb_cow_head - skb_cow but only making the head writable
1320 * @skb: buffer to cow
1321 * @headroom: needed headroom
1323 * This function is identical to skb_cow except that we replace the
1324 * skb_cloned check by skb_header_cloned. It should be used when
1325 * you only need to push on some header and do not need to modify
1328 static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
1330 return __skb_cow(skb, headroom, skb_header_cloned(skb));
1334 * skb_padto - pad an skbuff up to a minimal size
1335 * @skb: buffer to pad
1336 * @len: minimal length
1338 * Pads up a buffer to ensure the trailing bytes exist and are
1339 * blanked. If the buffer already contains sufficient data it
1340 * is untouched. Otherwise it is extended. Returns zero on
1341 * success. The skb is freed on error.
1344 static inline int skb_padto(struct sk_buff *skb, unsigned int len)
1346 unsigned int size = skb->len;
1347 if (likely(size >= len))
1349 return skb_pad(skb, len-size);
1352 static inline int skb_add_data(struct sk_buff *skb,
1353 char __user *from, int copy)
1355 const int off = skb->len;
1357 if (skb->ip_summed == CHECKSUM_NONE) {
1359 __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
1362 skb->csum = csum_block_add(skb->csum, csum, off);
1365 } else if (!copy_from_user(skb_put(skb, copy), from, copy))
1368 __skb_trim(skb, off);
1372 static inline int skb_can_coalesce(struct sk_buff *skb, int i,
1373 struct page *page, int off)
1376 struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
1378 return page == frag->page &&
1379 off == frag->page_offset + frag->size;
1384 static inline int __skb_linearize(struct sk_buff *skb)
1386 return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
1390 * skb_linearize - convert paged skb to linear one
1391 * @skb: buffer to linarize
1393 * If there is no free memory -ENOMEM is returned, otherwise zero
1394 * is returned and the old skb data released.
1396 static inline int skb_linearize(struct sk_buff *skb)
1398 return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
1402 * skb_linearize_cow - make sure skb is linear and writable
1403 * @skb: buffer to process
1405 * If there is no free memory -ENOMEM is returned, otherwise zero
1406 * is returned and the old skb data released.
1408 static inline int skb_linearize_cow(struct sk_buff *skb)
1410 return skb_is_nonlinear(skb) || skb_cloned(skb) ?
1411 __skb_linearize(skb) : 0;
1415 * skb_postpull_rcsum - update checksum for received skb after pull
1416 * @skb: buffer to update
1417 * @start: start of data before pull
1418 * @len: length of data pulled
1420 * After doing a pull on a received packet, you need to call this to
1421 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
1422 * CHECKSUM_NONE so that it can be recomputed from scratch.
1425 static inline void skb_postpull_rcsum(struct sk_buff *skb,
1426 const void *start, unsigned int len)
1428 if (skb->ip_summed == CHECKSUM_COMPLETE)
1429 skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
1432 unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
1435 * pskb_trim_rcsum - trim received skb and update checksum
1436 * @skb: buffer to trim
1439 * This is exactly the same as pskb_trim except that it ensures the
1440 * checksum of received packets are still valid after the operation.
1443 static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
1445 if (likely(len >= skb->len))
1447 if (skb->ip_summed == CHECKSUM_COMPLETE)
1448 skb->ip_summed = CHECKSUM_NONE;
1449 return __pskb_trim(skb, len);
1452 #define skb_queue_walk(queue, skb) \
1453 for (skb = (queue)->next; \
1454 prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
1457 #define skb_queue_walk_safe(queue, skb, tmp) \
1458 for (skb = (queue)->next, tmp = skb->next; \
1459 skb != (struct sk_buff *)(queue); \
1460 skb = tmp, tmp = skb->next)
1462 #define skb_queue_reverse_walk(queue, skb) \
1463 for (skb = (queue)->prev; \
1464 prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
1468 extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
1469 int *peeked, int *err);
1470 extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
1471 int noblock, int *err);
1472 extern unsigned int datagram_poll(struct file *file, struct socket *sock,
1473 struct poll_table_struct *wait);
1474 extern int skb_copy_datagram_iovec(const struct sk_buff *from,
1475 int offset, struct iovec *to,
1477 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
1480 extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
1481 extern int skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
1482 unsigned int flags);
1483 extern __wsum skb_checksum(const struct sk_buff *skb, int offset,
1484 int len, __wsum csum);
1485 extern int skb_copy_bits(const struct sk_buff *skb, int offset,
1487 extern int skb_store_bits(struct sk_buff *skb, int offset,
1488 const void *from, int len);
1489 extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb,
1490 int offset, u8 *to, int len,
1492 extern int skb_splice_bits(struct sk_buff *skb,
1493 unsigned int offset,
1494 struct pipe_inode_info *pipe,
1496 unsigned int flags);
1497 extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
1498 extern void skb_split(struct sk_buff *skb,
1499 struct sk_buff *skb1, const u32 len);
1501 extern struct sk_buff *skb_segment(struct sk_buff *skb, int features);
1503 static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
1504 int len, void *buffer)
1506 int hlen = skb_headlen(skb);
1508 if (hlen - offset >= len)
1509 return skb->data + offset;
1511 if (skb_copy_bits(skb, offset, buffer, len) < 0)
1517 static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
1519 const unsigned int len)
1521 memcpy(to, skb->data, len);
1524 static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
1525 const int offset, void *to,
1526 const unsigned int len)
1528 memcpy(to, skb->data + offset, len);
1531 static inline void skb_copy_to_linear_data(struct sk_buff *skb,
1533 const unsigned int len)
1535 memcpy(skb->data, from, len);
1538 static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
1541 const unsigned int len)
1543 memcpy(skb->data + offset, from, len);
1546 extern void skb_init(void);
1549 * skb_get_timestamp - get timestamp from a skb
1550 * @skb: skb to get stamp from
1551 * @stamp: pointer to struct timeval to store stamp in
1553 * Timestamps are stored in the skb as offsets to a base timestamp.
1554 * This function converts the offset back to a struct timeval and stores
1557 static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
1559 *stamp = ktime_to_timeval(skb->tstamp);
1562 static inline void __net_timestamp(struct sk_buff *skb)
1564 skb->tstamp = ktime_get_real();
1567 static inline ktime_t net_timedelta(ktime_t t)
1569 return ktime_sub(ktime_get_real(), t);
1572 static inline ktime_t net_invalid_timestamp(void)
1574 return ktime_set(0, 0);
1577 extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
1578 extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
1580 static inline int skb_csum_unnecessary(const struct sk_buff *skb)
1582 return skb->ip_summed & CHECKSUM_UNNECESSARY;
1586 * skb_checksum_complete - Calculate checksum of an entire packet
1587 * @skb: packet to process
1589 * This function calculates the checksum over the entire packet plus
1590 * the value of skb->csum. The latter can be used to supply the
1591 * checksum of a pseudo header as used by TCP/UDP. It returns the
1594 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
1595 * this function can be used to verify that checksum on received
1596 * packets. In that case the function should return zero if the
1597 * checksum is correct. In particular, this function will return zero
1598 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
1599 * hardware has already verified the correctness of the checksum.
1601 static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
1603 return skb_csum_unnecessary(skb) ?
1604 0 : __skb_checksum_complete(skb);
1607 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1608 extern void nf_conntrack_destroy(struct nf_conntrack *nfct);
1609 static inline void nf_conntrack_put(struct nf_conntrack *nfct)
1611 if (nfct && atomic_dec_and_test(&nfct->use))
1612 nf_conntrack_destroy(nfct);
1614 static inline void nf_conntrack_get(struct nf_conntrack *nfct)
1617 atomic_inc(&nfct->use);
1619 static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
1622 atomic_inc(&skb->users);
1624 static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
1630 #ifdef CONFIG_BRIDGE_NETFILTER
1631 static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
1633 if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
1636 static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
1639 atomic_inc(&nf_bridge->use);
1641 #endif /* CONFIG_BRIDGE_NETFILTER */
1642 static inline void nf_reset(struct sk_buff *skb)
1644 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1645 nf_conntrack_put(skb->nfct);
1647 nf_conntrack_put_reasm(skb->nfct_reasm);
1648 skb->nfct_reasm = NULL;
1650 #ifdef CONFIG_BRIDGE_NETFILTER
1651 nf_bridge_put(skb->nf_bridge);
1652 skb->nf_bridge = NULL;
1656 /* Note: This doesn't put any conntrack and bridge info in dst. */
1657 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1659 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1660 dst->nfct = src->nfct;
1661 nf_conntrack_get(src->nfct);
1662 dst->nfctinfo = src->nfctinfo;
1663 dst->nfct_reasm = src->nfct_reasm;
1664 nf_conntrack_get_reasm(src->nfct_reasm);
1666 #ifdef CONFIG_BRIDGE_NETFILTER
1667 dst->nf_bridge = src->nf_bridge;
1668 nf_bridge_get(src->nf_bridge);
1672 static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1674 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1675 nf_conntrack_put(dst->nfct);
1676 nf_conntrack_put_reasm(dst->nfct_reasm);
1678 #ifdef CONFIG_BRIDGE_NETFILTER
1679 nf_bridge_put(dst->nf_bridge);
1681 __nf_copy(dst, src);
1684 #ifdef CONFIG_NETWORK_SECMARK
1685 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1687 to->secmark = from->secmark;
1690 static inline void skb_init_secmark(struct sk_buff *skb)
1695 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1698 static inline void skb_init_secmark(struct sk_buff *skb)
1702 static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
1704 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1705 skb->queue_mapping = queue_mapping;
1709 static inline u16 skb_get_queue_mapping(struct sk_buff *skb)
1711 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1712 return skb->queue_mapping;
1718 static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
1720 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
1721 to->queue_mapping = from->queue_mapping;
1725 static inline int skb_is_gso(const struct sk_buff *skb)
1727 return skb_shinfo(skb)->gso_size;
1730 static inline int skb_is_gso_v6(const struct sk_buff *skb)
1732 return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
1735 static inline void skb_forward_csum(struct sk_buff *skb)
1737 /* Unfortunately we don't support this one. Any brave souls? */
1738 if (skb->ip_summed == CHECKSUM_COMPLETE)
1739 skb->ip_summed = CHECKSUM_NONE;
1742 bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
1743 #endif /* __KERNEL__ */
1744 #endif /* _LINUX_SKBUFF_H */