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 #ifdef CONFIG_HAS_DMA
150 unsigned int num_dma_maps;
152 struct sk_buff *frag_list;
153 skb_frag_t frags[MAX_SKB_FRAGS];
154 #ifdef CONFIG_HAS_DMA
155 dma_addr_t dma_maps[MAX_SKB_FRAGS + 1];
159 /* We divide dataref into two halves. The higher 16 bits hold references
160 * to the payload part of skb->data. The lower 16 bits hold references to
161 * the entire skb->data. A clone of a headerless skb holds the length of
162 * the header in skb->hdr_len.
164 * All users must obey the rule that the skb->data reference count must be
165 * greater than or equal to the payload reference count.
167 * Holding a reference to the payload part means that the user does not
168 * care about modifications to the header part of skb->data.
170 #define SKB_DATAREF_SHIFT 16
171 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
175 SKB_FCLONE_UNAVAILABLE,
181 SKB_GSO_TCPV4 = 1 << 0,
182 SKB_GSO_UDP = 1 << 1,
184 /* This indicates the skb is from an untrusted source. */
185 SKB_GSO_DODGY = 1 << 2,
187 /* This indicates the tcp segment has CWR set. */
188 SKB_GSO_TCP_ECN = 1 << 3,
190 SKB_GSO_TCPV6 = 1 << 4,
193 #if BITS_PER_LONG > 32
194 #define NET_SKBUFF_DATA_USES_OFFSET 1
197 #ifdef NET_SKBUFF_DATA_USES_OFFSET
198 typedef unsigned int sk_buff_data_t;
200 typedef unsigned char *sk_buff_data_t;
204 * struct sk_buff - socket buffer
205 * @next: Next buffer in list
206 * @prev: Previous buffer in list
207 * @sk: Socket we are owned by
208 * @tstamp: Time we arrived
209 * @dev: Device we arrived on/are leaving by
210 * @transport_header: Transport layer header
211 * @network_header: Network layer header
212 * @mac_header: Link layer header
213 * @dst: destination entry
214 * @sp: the security path, used for xfrm
215 * @cb: Control buffer. Free for use by every layer. Put private vars here
216 * @len: Length of actual data
217 * @data_len: Data length
218 * @mac_len: Length of link layer header
219 * @hdr_len: writable header length of cloned skb
220 * @csum: Checksum (must include start/offset pair)
221 * @csum_start: Offset from skb->head where checksumming should start
222 * @csum_offset: Offset from csum_start where checksum should be stored
223 * @local_df: allow local fragmentation
224 * @cloned: Head may be cloned (check refcnt to be sure)
225 * @nohdr: Payload reference only, must not modify header
226 * @pkt_type: Packet class
227 * @fclone: skbuff clone status
228 * @ip_summed: Driver fed us an IP checksum
229 * @priority: Packet queueing priority
230 * @users: User count - see {datagram,tcp}.c
231 * @protocol: Packet protocol from driver
232 * @truesize: Buffer size
233 * @head: Head of buffer
234 * @data: Data head pointer
235 * @tail: Tail pointer
237 * @destructor: Destruct function
238 * @mark: Generic packet mark
239 * @nfct: Associated connection, if any
240 * @ipvs_property: skbuff is owned by ipvs
241 * @peeked: this packet has been seen already, so stats have been
242 * done for it, don't do them again
243 * @nf_trace: netfilter packet trace flag
244 * @nfctinfo: Relationship of this skb to the connection
245 * @nfct_reasm: netfilter conntrack re-assembly pointer
246 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
247 * @iif: ifindex of device we arrived on
248 * @queue_mapping: Queue mapping for multiqueue devices
249 * @tc_index: Traffic control index
250 * @tc_verd: traffic control verdict
251 * @ndisc_nodetype: router type (from link layer)
252 * @do_not_encrypt: set to prevent encryption of this frame
253 * @dma_cookie: a cookie to one of several possible DMA operations
254 * done by skb DMA functions
255 * @secmark: security marking
256 * @vlan_tci: vlan tag control information
260 /* These two members must be first. */
261 struct sk_buff *next;
262 struct sk_buff *prev;
266 struct net_device *dev;
269 struct dst_entry *dst;
270 struct rtable *rtable;
275 * This is the control buffer. It is free to use for every
276 * layer. Please put your private variables there. If you
277 * want to keep them across layers you have to do a skb_clone()
278 * first. This is owned by whoever has the skb queued ATM.
306 void (*destructor)(struct sk_buff *skb);
307 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
308 struct nf_conntrack *nfct;
309 struct sk_buff *nfct_reasm;
311 #ifdef CONFIG_BRIDGE_NETFILTER
312 struct nf_bridge_info *nf_bridge;
317 #ifdef CONFIG_NET_SCHED
318 __u16 tc_index; /* traffic control index */
319 #ifdef CONFIG_NET_CLS_ACT
320 __u16 tc_verd; /* traffic control verdict */
323 #ifdef CONFIG_IPV6_NDISC_NODETYPE
324 __u8 ndisc_nodetype:2;
326 #if defined(CONFIG_MAC80211) || defined(CONFIG_MAC80211_MODULE)
327 __u8 do_not_encrypt:1;
329 /* 0/13/14 bit hole */
331 #ifdef CONFIG_NET_DMA
332 dma_cookie_t dma_cookie;
334 #ifdef CONFIG_NETWORK_SECMARK
342 sk_buff_data_t transport_header;
343 sk_buff_data_t network_header;
344 sk_buff_data_t mac_header;
345 /* These elements must be at the end, see alloc_skb() for details. */
350 unsigned int truesize;
356 * Handling routines are only of interest to the kernel
358 #include <linux/slab.h>
360 #include <asm/system.h>
362 #ifdef CONFIG_HAS_DMA
363 #include <linux/dma-mapping.h>
364 extern int skb_dma_map(struct device *dev, struct sk_buff *skb,
365 enum dma_data_direction dir);
366 extern void skb_dma_unmap(struct device *dev, struct sk_buff *skb,
367 enum dma_data_direction dir);
370 extern void kfree_skb(struct sk_buff *skb);
371 extern void __kfree_skb(struct sk_buff *skb);
372 extern struct sk_buff *__alloc_skb(unsigned int size,
373 gfp_t priority, int fclone, int node);
374 static inline struct sk_buff *alloc_skb(unsigned int size,
377 return __alloc_skb(size, priority, 0, -1);
380 static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
383 return __alloc_skb(size, priority, 1, -1);
386 extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
387 extern struct sk_buff *skb_clone(struct sk_buff *skb,
389 extern struct sk_buff *skb_copy(const struct sk_buff *skb,
391 extern struct sk_buff *pskb_copy(struct sk_buff *skb,
393 extern int pskb_expand_head(struct sk_buff *skb,
394 int nhead, int ntail,
396 extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
397 unsigned int headroom);
398 extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
399 int newheadroom, int newtailroom,
401 extern int skb_to_sgvec(struct sk_buff *skb,
402 struct scatterlist *sg, int offset,
404 extern int skb_cow_data(struct sk_buff *skb, int tailbits,
405 struct sk_buff **trailer);
406 extern int skb_pad(struct sk_buff *skb, int pad);
407 #define dev_kfree_skb(a) kfree_skb(a)
408 extern void skb_over_panic(struct sk_buff *skb, int len,
410 extern void skb_under_panic(struct sk_buff *skb, int len,
412 extern void skb_truesize_bug(struct sk_buff *skb);
414 static inline void skb_truesize_check(struct sk_buff *skb)
416 int len = sizeof(struct sk_buff) + skb->len;
418 if (unlikely((int)skb->truesize < len))
419 skb_truesize_bug(skb);
422 extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
423 int getfrag(void *from, char *to, int offset,
424 int len,int odd, struct sk_buff *skb),
425 void *from, int length);
432 __u32 stepped_offset;
433 struct sk_buff *root_skb;
434 struct sk_buff *cur_skb;
438 extern void skb_prepare_seq_read(struct sk_buff *skb,
439 unsigned int from, unsigned int to,
440 struct skb_seq_state *st);
441 extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
442 struct skb_seq_state *st);
443 extern void skb_abort_seq_read(struct skb_seq_state *st);
445 extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
446 unsigned int to, struct ts_config *config,
447 struct ts_state *state);
449 #ifdef NET_SKBUFF_DATA_USES_OFFSET
450 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
452 return skb->head + skb->end;
455 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
462 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
465 * skb_queue_empty - check if a queue is empty
468 * Returns true if the queue is empty, false otherwise.
470 static inline int skb_queue_empty(const struct sk_buff_head *list)
472 return list->next == (struct sk_buff *)list;
476 * skb_queue_is_last - check if skb is the last entry in the queue
480 * Returns true if @skb is the last buffer on the list.
482 static inline bool skb_queue_is_last(const struct sk_buff_head *list,
483 const struct sk_buff *skb)
485 return (skb->next == (struct sk_buff *) list);
489 * skb_get - reference buffer
490 * @skb: buffer to reference
492 * Makes another reference to a socket buffer and returns a pointer
495 static inline struct sk_buff *skb_get(struct sk_buff *skb)
497 atomic_inc(&skb->users);
502 * If users == 1, we are the only owner and are can avoid redundant
507 * skb_cloned - is the buffer a clone
508 * @skb: buffer to check
510 * Returns true if the buffer was generated with skb_clone() and is
511 * one of multiple shared copies of the buffer. Cloned buffers are
512 * shared data so must not be written to under normal circumstances.
514 static inline int skb_cloned(const struct sk_buff *skb)
516 return skb->cloned &&
517 (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
521 * skb_header_cloned - is the header a clone
522 * @skb: buffer to check
524 * Returns true if modifying the header part of the buffer requires
525 * the data to be copied.
527 static inline int skb_header_cloned(const struct sk_buff *skb)
534 dataref = atomic_read(&skb_shinfo(skb)->dataref);
535 dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
540 * skb_header_release - release reference to header
541 * @skb: buffer to operate on
543 * Drop a reference to the header part of the buffer. This is done
544 * by acquiring a payload reference. You must not read from the header
545 * part of skb->data after this.
547 static inline void skb_header_release(struct sk_buff *skb)
551 atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
555 * skb_shared - is the buffer shared
556 * @skb: buffer to check
558 * Returns true if more than one person has a reference to this
561 static inline int skb_shared(const struct sk_buff *skb)
563 return atomic_read(&skb->users) != 1;
567 * skb_share_check - check if buffer is shared and if so clone it
568 * @skb: buffer to check
569 * @pri: priority for memory allocation
571 * If the buffer is shared the buffer is cloned and the old copy
572 * drops a reference. A new clone with a single reference is returned.
573 * If the buffer is not shared the original buffer is returned. When
574 * being called from interrupt status or with spinlocks held pri must
577 * NULL is returned on a memory allocation failure.
579 static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
582 might_sleep_if(pri & __GFP_WAIT);
583 if (skb_shared(skb)) {
584 struct sk_buff *nskb = skb_clone(skb, pri);
592 * Copy shared buffers into a new sk_buff. We effectively do COW on
593 * packets to handle cases where we have a local reader and forward
594 * and a couple of other messy ones. The normal one is tcpdumping
595 * a packet thats being forwarded.
599 * skb_unshare - make a copy of a shared buffer
600 * @skb: buffer to check
601 * @pri: priority for memory allocation
603 * If the socket buffer is a clone then this function creates a new
604 * copy of the data, drops a reference count on the old copy and returns
605 * the new copy with the reference count at 1. If the buffer is not a clone
606 * the original buffer is returned. When called with a spinlock held or
607 * from interrupt state @pri must be %GFP_ATOMIC
609 * %NULL is returned on a memory allocation failure.
611 static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
614 might_sleep_if(pri & __GFP_WAIT);
615 if (skb_cloned(skb)) {
616 struct sk_buff *nskb = skb_copy(skb, pri);
617 kfree_skb(skb); /* Free our shared copy */
625 * @list_: list to peek at
627 * Peek an &sk_buff. Unlike most other operations you _MUST_
628 * be careful with this one. A peek leaves the buffer on the
629 * list and someone else may run off with it. You must hold
630 * the appropriate locks or have a private queue to do this.
632 * Returns %NULL for an empty list or a pointer to the head element.
633 * The reference count is not incremented and the reference is therefore
634 * volatile. Use with caution.
636 static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
638 struct sk_buff *list = ((struct sk_buff *)list_)->next;
639 if (list == (struct sk_buff *)list_)
646 * @list_: list to peek at
648 * Peek an &sk_buff. Unlike most other operations you _MUST_
649 * be careful with this one. A peek leaves the buffer on the
650 * list and someone else may run off with it. You must hold
651 * the appropriate locks or have a private queue to do this.
653 * Returns %NULL for an empty list or a pointer to the tail element.
654 * The reference count is not incremented and the reference is therefore
655 * volatile. Use with caution.
657 static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
659 struct sk_buff *list = ((struct sk_buff *)list_)->prev;
660 if (list == (struct sk_buff *)list_)
666 * skb_queue_len - get queue length
667 * @list_: list to measure
669 * Return the length of an &sk_buff queue.
671 static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
677 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
678 * @list: queue to initialize
680 * This initializes only the list and queue length aspects of
681 * an sk_buff_head object. This allows to initialize the list
682 * aspects of an sk_buff_head without reinitializing things like
683 * the spinlock. It can also be used for on-stack sk_buff_head
684 * objects where the spinlock is known to not be used.
686 static inline void __skb_queue_head_init(struct sk_buff_head *list)
688 list->prev = list->next = (struct sk_buff *)list;
693 * This function creates a split out lock class for each invocation;
694 * this is needed for now since a whole lot of users of the skb-queue
695 * infrastructure in drivers have different locking usage (in hardirq)
696 * than the networking core (in softirq only). In the long run either the
697 * network layer or drivers should need annotation to consolidate the
698 * main types of usage into 3 classes.
700 static inline void skb_queue_head_init(struct sk_buff_head *list)
702 spin_lock_init(&list->lock);
703 __skb_queue_head_init(list);
706 static inline void skb_queue_head_init_class(struct sk_buff_head *list,
707 struct lock_class_key *class)
709 skb_queue_head_init(list);
710 lockdep_set_class(&list->lock, class);
714 * Insert an sk_buff on a list.
716 * The "__skb_xxxx()" functions are the non-atomic ones that
717 * can only be called with interrupts disabled.
719 extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
720 static inline void __skb_insert(struct sk_buff *newsk,
721 struct sk_buff *prev, struct sk_buff *next,
722 struct sk_buff_head *list)
726 next->prev = prev->next = newsk;
730 static inline void __skb_queue_splice(const struct sk_buff_head *list,
731 struct sk_buff *prev,
732 struct sk_buff *next)
734 struct sk_buff *first = list->next;
735 struct sk_buff *last = list->prev;
745 * skb_queue_splice - join two skb lists, this is designed for stacks
746 * @list: the new list to add
747 * @head: the place to add it in the first list
749 static inline void skb_queue_splice(const struct sk_buff_head *list,
750 struct sk_buff_head *head)
752 if (!skb_queue_empty(list)) {
753 __skb_queue_splice(list, (struct sk_buff *) head, head->next);
754 head->qlen += list->qlen;
759 * skb_queue_splice - join two skb lists and reinitialise the emptied list
760 * @list: the new list to add
761 * @head: the place to add it in the first list
763 * The list at @list is reinitialised
765 static inline void skb_queue_splice_init(struct sk_buff_head *list,
766 struct sk_buff_head *head)
768 if (!skb_queue_empty(list)) {
769 __skb_queue_splice(list, (struct sk_buff *) head, head->next);
770 head->qlen += list->qlen;
771 __skb_queue_head_init(list);
776 * skb_queue_splice_tail - join two skb lists, each list being a queue
777 * @list: the new list to add
778 * @head: the place to add it in the first list
780 static inline void skb_queue_splice_tail(const struct sk_buff_head *list,
781 struct sk_buff_head *head)
783 if (!skb_queue_empty(list)) {
784 __skb_queue_splice(list, head->prev, (struct sk_buff *) head);
785 head->qlen += list->qlen;
790 * skb_queue_splice_tail - join two skb lists and reinitialise the emptied list
791 * @list: the new list to add
792 * @head: the place to add it in the first list
794 * Each of the lists is a queue.
795 * The list at @list is reinitialised
797 static inline void skb_queue_splice_tail_init(struct sk_buff_head *list,
798 struct sk_buff_head *head)
800 if (!skb_queue_empty(list)) {
801 __skb_queue_splice(list, head->prev, (struct sk_buff *) head);
802 head->qlen += list->qlen;
803 __skb_queue_head_init(list);
808 * __skb_queue_after - queue a buffer at the list head
810 * @prev: place after this buffer
811 * @newsk: buffer to queue
813 * Queue a buffer int the middle of a list. This function takes no locks
814 * and you must therefore hold required locks before calling it.
816 * A buffer cannot be placed on two lists at the same time.
818 static inline void __skb_queue_after(struct sk_buff_head *list,
819 struct sk_buff *prev,
820 struct sk_buff *newsk)
822 __skb_insert(newsk, prev, prev->next, list);
825 extern void skb_append(struct sk_buff *old, struct sk_buff *newsk,
826 struct sk_buff_head *list);
828 static inline void __skb_queue_before(struct sk_buff_head *list,
829 struct sk_buff *next,
830 struct sk_buff *newsk)
832 __skb_insert(newsk, next->prev, next, list);
836 * __skb_queue_head - queue a buffer at the list head
838 * @newsk: buffer to queue
840 * Queue a buffer at the start of a list. This function takes no locks
841 * and you must therefore hold required locks before calling it.
843 * A buffer cannot be placed on two lists at the same time.
845 extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
846 static inline void __skb_queue_head(struct sk_buff_head *list,
847 struct sk_buff *newsk)
849 __skb_queue_after(list, (struct sk_buff *)list, newsk);
853 * __skb_queue_tail - queue a buffer at the list tail
855 * @newsk: buffer to queue
857 * Queue a buffer at the end of a list. This function takes no locks
858 * and you must therefore hold required locks before calling it.
860 * A buffer cannot be placed on two lists at the same time.
862 extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
863 static inline void __skb_queue_tail(struct sk_buff_head *list,
864 struct sk_buff *newsk)
866 __skb_queue_before(list, (struct sk_buff *)list, newsk);
870 * remove sk_buff from list. _Must_ be called atomically, and with
873 extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
874 static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
876 struct sk_buff *next, *prev;
881 skb->next = skb->prev = NULL;
887 * __skb_dequeue - remove from the head of the queue
888 * @list: list to dequeue from
890 * Remove the head of the list. This function does not take any locks
891 * so must be used with appropriate locks held only. The head item is
892 * returned or %NULL if the list is empty.
894 extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
895 static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
897 struct sk_buff *skb = skb_peek(list);
899 __skb_unlink(skb, list);
904 * __skb_dequeue_tail - remove from the tail of the queue
905 * @list: list to dequeue from
907 * Remove the tail of the list. This function does not take any locks
908 * so must be used with appropriate locks held only. The tail item is
909 * returned or %NULL if the list is empty.
911 extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
912 static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
914 struct sk_buff *skb = skb_peek_tail(list);
916 __skb_unlink(skb, list);
921 static inline int skb_is_nonlinear(const struct sk_buff *skb)
923 return skb->data_len;
926 static inline unsigned int skb_headlen(const struct sk_buff *skb)
928 return skb->len - skb->data_len;
931 static inline int skb_pagelen(const struct sk_buff *skb)
935 for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
936 len += skb_shinfo(skb)->frags[i].size;
937 return len + skb_headlen(skb);
940 static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
941 struct page *page, int off, int size)
943 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
946 frag->page_offset = off;
948 skb_shinfo(skb)->nr_frags = i + 1;
951 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
952 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
953 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
955 #ifdef NET_SKBUFF_DATA_USES_OFFSET
956 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
958 return skb->head + skb->tail;
961 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
963 skb->tail = skb->data - skb->head;
966 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
968 skb_reset_tail_pointer(skb);
971 #else /* NET_SKBUFF_DATA_USES_OFFSET */
972 static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
977 static inline void skb_reset_tail_pointer(struct sk_buff *skb)
979 skb->tail = skb->data;
982 static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
984 skb->tail = skb->data + offset;
987 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
990 * Add data to an sk_buff
992 extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
993 static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
995 unsigned char *tmp = skb_tail_pointer(skb);
996 SKB_LINEAR_ASSERT(skb);
1002 extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len);
1003 static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
1010 extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);
1011 static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
1014 BUG_ON(skb->len < skb->data_len);
1015 return skb->data += len;
1018 extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
1020 static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
1022 if (len > skb_headlen(skb) &&
1023 !__pskb_pull_tail(skb, len - skb_headlen(skb)))
1026 return skb->data += len;
1029 static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
1031 return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
1034 static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
1036 if (likely(len <= skb_headlen(skb)))
1038 if (unlikely(len > skb->len))
1040 return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL;
1044 * skb_headroom - bytes at buffer head
1045 * @skb: buffer to check
1047 * Return the number of bytes of free space at the head of an &sk_buff.
1049 static inline unsigned int skb_headroom(const struct sk_buff *skb)
1051 return skb->data - skb->head;
1055 * skb_tailroom - bytes at buffer end
1056 * @skb: buffer to check
1058 * Return the number of bytes of free space at the tail of an sk_buff
1060 static inline int skb_tailroom(const struct sk_buff *skb)
1062 return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
1066 * skb_reserve - adjust headroom
1067 * @skb: buffer to alter
1068 * @len: bytes to move
1070 * Increase the headroom of an empty &sk_buff by reducing the tail
1071 * room. This is only allowed for an empty buffer.
1073 static inline void skb_reserve(struct sk_buff *skb, int len)
1079 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1080 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
1082 return skb->head + skb->transport_header;
1085 static inline void skb_reset_transport_header(struct sk_buff *skb)
1087 skb->transport_header = skb->data - skb->head;
1090 static inline void skb_set_transport_header(struct sk_buff *skb,
1093 skb_reset_transport_header(skb);
1094 skb->transport_header += offset;
1097 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1099 return skb->head + skb->network_header;
1102 static inline void skb_reset_network_header(struct sk_buff *skb)
1104 skb->network_header = skb->data - skb->head;
1107 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1109 skb_reset_network_header(skb);
1110 skb->network_header += offset;
1113 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1115 return skb->head + skb->mac_header;
1118 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1120 return skb->mac_header != ~0U;
1123 static inline void skb_reset_mac_header(struct sk_buff *skb)
1125 skb->mac_header = skb->data - skb->head;
1128 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1130 skb_reset_mac_header(skb);
1131 skb->mac_header += offset;
1134 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1136 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
1138 return skb->transport_header;
1141 static inline void skb_reset_transport_header(struct sk_buff *skb)
1143 skb->transport_header = skb->data;
1146 static inline void skb_set_transport_header(struct sk_buff *skb,
1149 skb->transport_header = skb->data + offset;
1152 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
1154 return skb->network_header;
1157 static inline void skb_reset_network_header(struct sk_buff *skb)
1159 skb->network_header = skb->data;
1162 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
1164 skb->network_header = skb->data + offset;
1167 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
1169 return skb->mac_header;
1172 static inline int skb_mac_header_was_set(const struct sk_buff *skb)
1174 return skb->mac_header != NULL;
1177 static inline void skb_reset_mac_header(struct sk_buff *skb)
1179 skb->mac_header = skb->data;
1182 static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
1184 skb->mac_header = skb->data + offset;
1186 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1188 static inline int skb_transport_offset(const struct sk_buff *skb)
1190 return skb_transport_header(skb) - skb->data;
1193 static inline u32 skb_network_header_len(const struct sk_buff *skb)
1195 return skb->transport_header - skb->network_header;
1198 static inline int skb_network_offset(const struct sk_buff *skb)
1200 return skb_network_header(skb) - skb->data;
1204 * CPUs often take a performance hit when accessing unaligned memory
1205 * locations. The actual performance hit varies, it can be small if the
1206 * hardware handles it or large if we have to take an exception and fix it
1209 * Since an ethernet header is 14 bytes network drivers often end up with
1210 * the IP header at an unaligned offset. The IP header can be aligned by
1211 * shifting the start of the packet by 2 bytes. Drivers should do this
1214 * skb_reserve(NET_IP_ALIGN);
1216 * The downside to this alignment of the IP header is that the DMA is now
1217 * unaligned. On some architectures the cost of an unaligned DMA is high
1218 * and this cost outweighs the gains made by aligning the IP header.
1220 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1223 #ifndef NET_IP_ALIGN
1224 #define NET_IP_ALIGN 2
1228 * The networking layer reserves some headroom in skb data (via
1229 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1230 * the header has to grow. In the default case, if the header has to grow
1231 * 16 bytes or less we avoid the reallocation.
1233 * Unfortunately this headroom changes the DMA alignment of the resulting
1234 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1235 * on some architectures. An architecture can override this value,
1236 * perhaps setting it to a cacheline in size (since that will maintain
1237 * cacheline alignment of the DMA). It must be a power of 2.
1239 * Various parts of the networking layer expect at least 16 bytes of
1240 * headroom, you should not reduce this.
1243 #define NET_SKB_PAD 16
1246 extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
1248 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
1250 if (unlikely(skb->data_len)) {
1255 skb_set_tail_pointer(skb, len);
1258 extern void skb_trim(struct sk_buff *skb, unsigned int len);
1260 static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
1263 return ___pskb_trim(skb, len);
1264 __skb_trim(skb, len);
1268 static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
1270 return (len < skb->len) ? __pskb_trim(skb, len) : 0;
1274 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1275 * @skb: buffer to alter
1278 * This is identical to pskb_trim except that the caller knows that
1279 * the skb is not cloned so we should never get an error due to out-
1282 static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
1284 int err = pskb_trim(skb, len);
1289 * skb_orphan - orphan a buffer
1290 * @skb: buffer to orphan
1292 * If a buffer currently has an owner then we call the owner's
1293 * destructor function and make the @skb unowned. The buffer continues
1294 * to exist but is no longer charged to its former owner.
1296 static inline void skb_orphan(struct sk_buff *skb)
1298 if (skb->destructor)
1299 skb->destructor(skb);
1300 skb->destructor = NULL;
1305 * __skb_queue_purge - empty a list
1306 * @list: list to empty
1308 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1309 * the list and one reference dropped. This function does not take the
1310 * list lock and the caller must hold the relevant locks to use it.
1312 extern void skb_queue_purge(struct sk_buff_head *list);
1313 static inline void __skb_queue_purge(struct sk_buff_head *list)
1315 struct sk_buff *skb;
1316 while ((skb = __skb_dequeue(list)) != NULL)
1321 * __dev_alloc_skb - allocate an skbuff for receiving
1322 * @length: length to allocate
1323 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1325 * Allocate a new &sk_buff and assign it a usage count of one. The
1326 * buffer has unspecified headroom built in. Users should allocate
1327 * the headroom they think they need without accounting for the
1328 * built in space. The built in space is used for optimisations.
1330 * %NULL is returned if there is no free memory.
1332 static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
1335 struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
1337 skb_reserve(skb, NET_SKB_PAD);
1341 extern struct sk_buff *dev_alloc_skb(unsigned int length);
1343 extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
1344 unsigned int length, gfp_t gfp_mask);
1347 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1348 * @dev: network device to receive on
1349 * @length: length to allocate
1351 * Allocate a new &sk_buff and assign it a usage count of one. The
1352 * buffer has unspecified headroom built in. Users should allocate
1353 * the headroom they think they need without accounting for the
1354 * built in space. The built in space is used for optimisations.
1356 * %NULL is returned if there is no free memory. Although this function
1357 * allocates memory it can be called from an interrupt.
1359 static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
1360 unsigned int length)
1362 return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
1366 * skb_clone_writable - is the header of a clone writable
1367 * @skb: buffer to check
1368 * @len: length up to which to write
1370 * Returns true if modifying the header part of the cloned buffer
1371 * does not requires the data to be copied.
1373 static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len)
1375 return !skb_header_cloned(skb) &&
1376 skb_headroom(skb) + len <= skb->hdr_len;
1379 static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
1384 if (headroom < NET_SKB_PAD)
1385 headroom = NET_SKB_PAD;
1386 if (headroom > skb_headroom(skb))
1387 delta = headroom - skb_headroom(skb);
1389 if (delta || cloned)
1390 return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
1396 * skb_cow - copy header of skb when it is required
1397 * @skb: buffer to cow
1398 * @headroom: needed headroom
1400 * If the skb passed lacks sufficient headroom or its data part
1401 * is shared, data is reallocated. If reallocation fails, an error
1402 * is returned and original skb is not changed.
1404 * The result is skb with writable area skb->head...skb->tail
1405 * and at least @headroom of space at head.
1407 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
1409 return __skb_cow(skb, headroom, skb_cloned(skb));
1413 * skb_cow_head - skb_cow but only making the head writable
1414 * @skb: buffer to cow
1415 * @headroom: needed headroom
1417 * This function is identical to skb_cow except that we replace the
1418 * skb_cloned check by skb_header_cloned. It should be used when
1419 * you only need to push on some header and do not need to modify
1422 static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
1424 return __skb_cow(skb, headroom, skb_header_cloned(skb));
1428 * skb_padto - pad an skbuff up to a minimal size
1429 * @skb: buffer to pad
1430 * @len: minimal length
1432 * Pads up a buffer to ensure the trailing bytes exist and are
1433 * blanked. If the buffer already contains sufficient data it
1434 * is untouched. Otherwise it is extended. Returns zero on
1435 * success. The skb is freed on error.
1438 static inline int skb_padto(struct sk_buff *skb, unsigned int len)
1440 unsigned int size = skb->len;
1441 if (likely(size >= len))
1443 return skb_pad(skb, len - size);
1446 static inline int skb_add_data(struct sk_buff *skb,
1447 char __user *from, int copy)
1449 const int off = skb->len;
1451 if (skb->ip_summed == CHECKSUM_NONE) {
1453 __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy),
1456 skb->csum = csum_block_add(skb->csum, csum, off);
1459 } else if (!copy_from_user(skb_put(skb, copy), from, copy))
1462 __skb_trim(skb, off);
1466 static inline int skb_can_coalesce(struct sk_buff *skb, int i,
1467 struct page *page, int off)
1470 struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
1472 return page == frag->page &&
1473 off == frag->page_offset + frag->size;
1478 static inline int __skb_linearize(struct sk_buff *skb)
1480 return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
1484 * skb_linearize - convert paged skb to linear one
1485 * @skb: buffer to linarize
1487 * If there is no free memory -ENOMEM is returned, otherwise zero
1488 * is returned and the old skb data released.
1490 static inline int skb_linearize(struct sk_buff *skb)
1492 return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
1496 * skb_linearize_cow - make sure skb is linear and writable
1497 * @skb: buffer to process
1499 * If there is no free memory -ENOMEM is returned, otherwise zero
1500 * is returned and the old skb data released.
1502 static inline int skb_linearize_cow(struct sk_buff *skb)
1504 return skb_is_nonlinear(skb) || skb_cloned(skb) ?
1505 __skb_linearize(skb) : 0;
1509 * skb_postpull_rcsum - update checksum for received skb after pull
1510 * @skb: buffer to update
1511 * @start: start of data before pull
1512 * @len: length of data pulled
1514 * After doing a pull on a received packet, you need to call this to
1515 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
1516 * CHECKSUM_NONE so that it can be recomputed from scratch.
1519 static inline void skb_postpull_rcsum(struct sk_buff *skb,
1520 const void *start, unsigned int len)
1522 if (skb->ip_summed == CHECKSUM_COMPLETE)
1523 skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
1526 unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
1529 * pskb_trim_rcsum - trim received skb and update checksum
1530 * @skb: buffer to trim
1533 * This is exactly the same as pskb_trim except that it ensures the
1534 * checksum of received packets are still valid after the operation.
1537 static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
1539 if (likely(len >= skb->len))
1541 if (skb->ip_summed == CHECKSUM_COMPLETE)
1542 skb->ip_summed = CHECKSUM_NONE;
1543 return __pskb_trim(skb, len);
1546 #define skb_queue_walk(queue, skb) \
1547 for (skb = (queue)->next; \
1548 prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
1551 #define skb_queue_walk_safe(queue, skb, tmp) \
1552 for (skb = (queue)->next, tmp = skb->next; \
1553 skb != (struct sk_buff *)(queue); \
1554 skb = tmp, tmp = skb->next)
1556 #define skb_queue_reverse_walk(queue, skb) \
1557 for (skb = (queue)->prev; \
1558 prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
1562 extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
1563 int *peeked, int *err);
1564 extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
1565 int noblock, int *err);
1566 extern unsigned int datagram_poll(struct file *file, struct socket *sock,
1567 struct poll_table_struct *wait);
1568 extern int skb_copy_datagram_iovec(const struct sk_buff *from,
1569 int offset, struct iovec *to,
1571 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
1574 extern int skb_copy_datagram_from_iovec(struct sk_buff *skb,
1578 extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
1579 extern int skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
1580 unsigned int flags);
1581 extern __wsum skb_checksum(const struct sk_buff *skb, int offset,
1582 int len, __wsum csum);
1583 extern int skb_copy_bits(const struct sk_buff *skb, int offset,
1585 extern int skb_store_bits(struct sk_buff *skb, int offset,
1586 const void *from, int len);
1587 extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb,
1588 int offset, u8 *to, int len,
1590 extern int skb_splice_bits(struct sk_buff *skb,
1591 unsigned int offset,
1592 struct pipe_inode_info *pipe,
1594 unsigned int flags);
1595 extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
1596 extern void skb_split(struct sk_buff *skb,
1597 struct sk_buff *skb1, const u32 len);
1599 extern struct sk_buff *skb_segment(struct sk_buff *skb, int features);
1601 static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
1602 int len, void *buffer)
1604 int hlen = skb_headlen(skb);
1606 if (hlen - offset >= len)
1607 return skb->data + offset;
1609 if (skb_copy_bits(skb, offset, buffer, len) < 0)
1615 static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
1617 const unsigned int len)
1619 memcpy(to, skb->data, len);
1622 static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
1623 const int offset, void *to,
1624 const unsigned int len)
1626 memcpy(to, skb->data + offset, len);
1629 static inline void skb_copy_to_linear_data(struct sk_buff *skb,
1631 const unsigned int len)
1633 memcpy(skb->data, from, len);
1636 static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
1639 const unsigned int len)
1641 memcpy(skb->data + offset, from, len);
1644 extern void skb_init(void);
1647 * skb_get_timestamp - get timestamp from a skb
1648 * @skb: skb to get stamp from
1649 * @stamp: pointer to struct timeval to store stamp in
1651 * Timestamps are stored in the skb as offsets to a base timestamp.
1652 * This function converts the offset back to a struct timeval and stores
1655 static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
1657 *stamp = ktime_to_timeval(skb->tstamp);
1660 static inline void __net_timestamp(struct sk_buff *skb)
1662 skb->tstamp = ktime_get_real();
1665 static inline ktime_t net_timedelta(ktime_t t)
1667 return ktime_sub(ktime_get_real(), t);
1670 static inline ktime_t net_invalid_timestamp(void)
1672 return ktime_set(0, 0);
1675 extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
1676 extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
1678 static inline int skb_csum_unnecessary(const struct sk_buff *skb)
1680 return skb->ip_summed & CHECKSUM_UNNECESSARY;
1684 * skb_checksum_complete - Calculate checksum of an entire packet
1685 * @skb: packet to process
1687 * This function calculates the checksum over the entire packet plus
1688 * the value of skb->csum. The latter can be used to supply the
1689 * checksum of a pseudo header as used by TCP/UDP. It returns the
1692 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
1693 * this function can be used to verify that checksum on received
1694 * packets. In that case the function should return zero if the
1695 * checksum is correct. In particular, this function will return zero
1696 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
1697 * hardware has already verified the correctness of the checksum.
1699 static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
1701 return skb_csum_unnecessary(skb) ?
1702 0 : __skb_checksum_complete(skb);
1705 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1706 extern void nf_conntrack_destroy(struct nf_conntrack *nfct);
1707 static inline void nf_conntrack_put(struct nf_conntrack *nfct)
1709 if (nfct && atomic_dec_and_test(&nfct->use))
1710 nf_conntrack_destroy(nfct);
1712 static inline void nf_conntrack_get(struct nf_conntrack *nfct)
1715 atomic_inc(&nfct->use);
1717 static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
1720 atomic_inc(&skb->users);
1722 static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
1728 #ifdef CONFIG_BRIDGE_NETFILTER
1729 static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
1731 if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
1734 static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
1737 atomic_inc(&nf_bridge->use);
1739 #endif /* CONFIG_BRIDGE_NETFILTER */
1740 static inline void nf_reset(struct sk_buff *skb)
1742 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1743 nf_conntrack_put(skb->nfct);
1745 nf_conntrack_put_reasm(skb->nfct_reasm);
1746 skb->nfct_reasm = NULL;
1748 #ifdef CONFIG_BRIDGE_NETFILTER
1749 nf_bridge_put(skb->nf_bridge);
1750 skb->nf_bridge = NULL;
1754 /* Note: This doesn't put any conntrack and bridge info in dst. */
1755 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1757 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1758 dst->nfct = src->nfct;
1759 nf_conntrack_get(src->nfct);
1760 dst->nfctinfo = src->nfctinfo;
1761 dst->nfct_reasm = src->nfct_reasm;
1762 nf_conntrack_get_reasm(src->nfct_reasm);
1764 #ifdef CONFIG_BRIDGE_NETFILTER
1765 dst->nf_bridge = src->nf_bridge;
1766 nf_bridge_get(src->nf_bridge);
1770 static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
1772 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1773 nf_conntrack_put(dst->nfct);
1774 nf_conntrack_put_reasm(dst->nfct_reasm);
1776 #ifdef CONFIG_BRIDGE_NETFILTER
1777 nf_bridge_put(dst->nf_bridge);
1779 __nf_copy(dst, src);
1782 #ifdef CONFIG_NETWORK_SECMARK
1783 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1785 to->secmark = from->secmark;
1788 static inline void skb_init_secmark(struct sk_buff *skb)
1793 static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
1796 static inline void skb_init_secmark(struct sk_buff *skb)
1800 static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
1802 skb->queue_mapping = queue_mapping;
1805 static inline u16 skb_get_queue_mapping(struct sk_buff *skb)
1807 return skb->queue_mapping;
1810 static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
1812 to->queue_mapping = from->queue_mapping;
1815 static inline int skb_is_gso(const struct sk_buff *skb)
1817 return skb_shinfo(skb)->gso_size;
1820 static inline int skb_is_gso_v6(const struct sk_buff *skb)
1822 return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
1825 extern void __skb_warn_lro_forwarding(const struct sk_buff *skb);
1827 static inline bool skb_warn_if_lro(const struct sk_buff *skb)
1829 /* LRO sets gso_size but not gso_type, whereas if GSO is really
1830 * wanted then gso_type will be set. */
1831 struct skb_shared_info *shinfo = skb_shinfo(skb);
1832 if (shinfo->gso_size != 0 && unlikely(shinfo->gso_type == 0)) {
1833 __skb_warn_lro_forwarding(skb);
1839 static inline void skb_forward_csum(struct sk_buff *skb)
1841 /* Unfortunately we don't support this one. Any brave souls? */
1842 if (skb->ip_summed == CHECKSUM_COMPLETE)
1843 skb->ip_summed = CHECKSUM_NONE;
1846 bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
1847 #endif /* __KERNEL__ */
1848 #endif /* _LINUX_SKBUFF_H */