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/kmemcheck.h>
19 #include <linux/compiler.h>
20 #include <linux/time.h>
21 #include <linux/bug.h>
22 #include <linux/cache.h>
24 #include <linux/atomic.h>
25 #include <asm/types.h>
26 #include <linux/spinlock.h>
27 #include <linux/net.h>
28 #include <linux/textsearch.h>
29 #include <net/checksum.h>
30 #include <linux/rcupdate.h>
31 #include <linux/dmaengine.h>
32 #include <linux/hrtimer.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/netdev_features.h>
36 /* Don't change this without changing skb_csum_unnecessary! */
37 #define CHECKSUM_NONE 0
38 #define CHECKSUM_UNNECESSARY 1
39 #define CHECKSUM_COMPLETE 2
40 #define CHECKSUM_PARTIAL 3
42 #define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \
43 ~(SMP_CACHE_BYTES - 1))
44 #define SKB_WITH_OVERHEAD(X) \
45 ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
46 #define SKB_MAX_ORDER(X, ORDER) \
47 SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
48 #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
49 #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
51 /* return minimum truesize of one skb containing X bytes of data */
52 #define SKB_TRUESIZE(X) ((X) + \
53 SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \
54 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
56 /* A. Checksumming of received packets by device.
58 * NONE: device failed to checksum this packet.
59 * skb->csum is undefined.
61 * UNNECESSARY: device parsed packet and wouldbe verified checksum.
62 * skb->csum is undefined.
63 * It is bad option, but, unfortunately, many of vendors do this.
64 * Apparently with secret goal to sell you new device, when you
65 * will add new protocol to your host. F.e. IPv6. 8)
67 * COMPLETE: the most generic way. Device supplied checksum of _all_
68 * the packet as seen by netif_rx in skb->csum.
69 * NOTE: Even if device supports only some protocols, but
70 * is able to produce some skb->csum, it MUST use COMPLETE,
73 * PARTIAL: identical to the case for output below. This may occur
74 * on a packet received directly from another Linux OS, e.g.,
75 * a virtualised Linux kernel on the same host. The packet can
76 * be treated in the same way as UNNECESSARY except that on
77 * output (i.e., forwarding) the checksum must be filled in
78 * by the OS or the hardware.
80 * B. Checksumming on output.
82 * NONE: skb is checksummed by protocol or csum is not required.
84 * PARTIAL: device is required to csum packet as seen by hard_start_xmit
85 * from skb->csum_start to the end and to record the checksum
86 * at skb->csum_start + skb->csum_offset.
88 * Device must show its capabilities in dev->features, set
89 * at device setup time.
90 * NETIF_F_HW_CSUM - it is clever device, it is able to checksum
92 * NETIF_F_IP_CSUM - device is dumb. It is able to csum only
93 * TCP/UDP over IPv4. Sigh. Vendors like this
94 * way by an unknown reason. Though, see comment above
95 * about CHECKSUM_UNNECESSARY. 8)
96 * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead.
98 * UNNECESSARY: device will do per protocol specific csum. Protocol drivers
99 * that do not want net to perform the checksum calculation should use
100 * this flag in their outgoing skbs.
101 * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC
102 * offload. Correspondingly, the FCoE protocol driver
103 * stack should use CHECKSUM_UNNECESSARY.
105 * Any questions? No questions, good. --ANK
110 struct pipe_inode_info
;
112 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
113 struct nf_conntrack
{
118 #ifdef CONFIG_BRIDGE_NETFILTER
119 struct nf_bridge_info
{
121 struct net_device
*physindev
;
122 struct net_device
*physoutdev
;
124 unsigned long data
[32 / sizeof(unsigned long)];
128 struct sk_buff_head
{
129 /* These two members must be first. */
130 struct sk_buff
*next
;
131 struct sk_buff
*prev
;
139 /* To allow 64K frame to be packed as single skb without frag_list we
140 * require 64K/PAGE_SIZE pages plus 1 additional page to allow for
141 * buffers which do not start on a page boundary.
143 * Since GRO uses frags we allocate at least 16 regardless of page
146 #if (65536/PAGE_SIZE + 1) < 16
147 #define MAX_SKB_FRAGS 16UL
149 #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1)
152 typedef struct skb_frag_struct skb_frag_t
;
154 struct skb_frag_struct
{
158 #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
167 static inline unsigned int skb_frag_size(const skb_frag_t
*frag
)
172 static inline void skb_frag_size_set(skb_frag_t
*frag
, unsigned int size
)
177 static inline void skb_frag_size_add(skb_frag_t
*frag
, int delta
)
182 static inline void skb_frag_size_sub(skb_frag_t
*frag
, int delta
)
187 #define HAVE_HW_TIME_STAMP
190 * struct skb_shared_hwtstamps - hardware time stamps
191 * @hwtstamp: hardware time stamp transformed into duration
192 * since arbitrary point in time
193 * @syststamp: hwtstamp transformed to system time base
195 * Software time stamps generated by ktime_get_real() are stored in
196 * skb->tstamp. The relation between the different kinds of time
197 * stamps is as follows:
199 * syststamp and tstamp can be compared against each other in
200 * arbitrary combinations. The accuracy of a
201 * syststamp/tstamp/"syststamp from other device" comparison is
202 * limited by the accuracy of the transformation into system time
203 * base. This depends on the device driver and its underlying
206 * hwtstamps can only be compared against other hwtstamps from
209 * This structure is attached to packets as part of the
210 * &skb_shared_info. Use skb_hwtstamps() to get a pointer.
212 struct skb_shared_hwtstamps
{
217 /* Definitions for tx_flags in struct skb_shared_info */
219 /* generate hardware time stamp */
220 SKBTX_HW_TSTAMP
= 1 << 0,
222 /* generate software time stamp */
223 SKBTX_SW_TSTAMP
= 1 << 1,
225 /* device driver is going to provide hardware time stamp */
226 SKBTX_IN_PROGRESS
= 1 << 2,
228 /* ensure the originating sk reference is available on driver level */
229 SKBTX_DRV_NEEDS_SK_REF
= 1 << 3,
231 /* device driver supports TX zero-copy buffers */
232 SKBTX_DEV_ZEROCOPY
= 1 << 4,
234 /* generate wifi status information (where possible) */
235 SKBTX_WIFI_STATUS
= 1 << 5,
239 * The callback notifies userspace to release buffers when skb DMA is done in
240 * lower device, the skb last reference should be 0 when calling this.
241 * The desc is used to track userspace buffer index.
244 void (*callback
)(void *);
249 /* This data is invariant across clones and lives at
250 * the end of the header data, ie. at skb->end.
252 struct skb_shared_info
{
253 unsigned char nr_frags
;
255 unsigned short gso_size
;
256 /* Warning: this field is not always filled in (UFO)! */
257 unsigned short gso_segs
;
258 unsigned short gso_type
;
259 struct sk_buff
*frag_list
;
260 struct skb_shared_hwtstamps hwtstamps
;
264 * Warning : all fields before dataref are cleared in __alloc_skb()
268 /* Intermediate layers must ensure that destructor_arg
269 * remains valid until skb destructor */
270 void * destructor_arg
;
272 /* must be last field, see pskb_expand_head() */
273 skb_frag_t frags
[MAX_SKB_FRAGS
];
276 /* We divide dataref into two halves. The higher 16 bits hold references
277 * to the payload part of skb->data. The lower 16 bits hold references to
278 * the entire skb->data. A clone of a headerless skb holds the length of
279 * the header in skb->hdr_len.
281 * All users must obey the rule that the skb->data reference count must be
282 * greater than or equal to the payload reference count.
284 * Holding a reference to the payload part means that the user does not
285 * care about modifications to the header part of skb->data.
287 #define SKB_DATAREF_SHIFT 16
288 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
292 SKB_FCLONE_UNAVAILABLE
,
298 SKB_GSO_TCPV4
= 1 << 0,
299 SKB_GSO_UDP
= 1 << 1,
301 /* This indicates the skb is from an untrusted source. */
302 SKB_GSO_DODGY
= 1 << 2,
304 /* This indicates the tcp segment has CWR set. */
305 SKB_GSO_TCP_ECN
= 1 << 3,
307 SKB_GSO_TCPV6
= 1 << 4,
309 SKB_GSO_FCOE
= 1 << 5,
312 #if BITS_PER_LONG > 32
313 #define NET_SKBUFF_DATA_USES_OFFSET 1
316 #ifdef NET_SKBUFF_DATA_USES_OFFSET
317 typedef unsigned int sk_buff_data_t
;
319 typedef unsigned char *sk_buff_data_t
;
322 #if defined(CONFIG_NF_DEFRAG_IPV4) || defined(CONFIG_NF_DEFRAG_IPV4_MODULE) || \
323 defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
324 #define NET_SKBUFF_NF_DEFRAG_NEEDED 1
328 * struct sk_buff - socket buffer
329 * @next: Next buffer in list
330 * @prev: Previous buffer in list
331 * @tstamp: Time we arrived
332 * @sk: Socket we are owned by
333 * @dev: Device we arrived on/are leaving by
334 * @cb: Control buffer. Free for use by every layer. Put private vars here
335 * @_skb_refdst: destination entry (with norefcount bit)
336 * @sp: the security path, used for xfrm
337 * @len: Length of actual data
338 * @data_len: Data length
339 * @mac_len: Length of link layer header
340 * @hdr_len: writable header length of cloned skb
341 * @csum: Checksum (must include start/offset pair)
342 * @csum_start: Offset from skb->head where checksumming should start
343 * @csum_offset: Offset from csum_start where checksum should be stored
344 * @priority: Packet queueing priority
345 * @local_df: allow local fragmentation
346 * @cloned: Head may be cloned (check refcnt to be sure)
347 * @ip_summed: Driver fed us an IP checksum
348 * @nohdr: Payload reference only, must not modify header
349 * @nfctinfo: Relationship of this skb to the connection
350 * @pkt_type: Packet class
351 * @fclone: skbuff clone status
352 * @ipvs_property: skbuff is owned by ipvs
353 * @peeked: this packet has been seen already, so stats have been
354 * done for it, don't do them again
355 * @nf_trace: netfilter packet trace flag
356 * @protocol: Packet protocol from driver
357 * @destructor: Destruct function
358 * @nfct: Associated connection, if any
359 * @nfct_reasm: netfilter conntrack re-assembly pointer
360 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
361 * @skb_iif: ifindex of device we arrived on
362 * @tc_index: Traffic control index
363 * @tc_verd: traffic control verdict
364 * @rxhash: the packet hash computed on receive
365 * @queue_mapping: Queue mapping for multiqueue devices
366 * @ndisc_nodetype: router type (from link layer)
367 * @ooo_okay: allow the mapping of a socket to a queue to be changed
368 * @l4_rxhash: indicate rxhash is a canonical 4-tuple hash over transport
370 * @wifi_acked_valid: wifi_acked was set
371 * @wifi_acked: whether frame was acked on wifi or not
372 * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS
373 * @dma_cookie: a cookie to one of several possible DMA operations
374 * done by skb DMA functions
375 * @secmark: security marking
376 * @mark: Generic packet mark
377 * @dropcount: total number of sk_receive_queue overflows
378 * @vlan_tci: vlan tag control information
379 * @transport_header: Transport layer header
380 * @network_header: Network layer header
381 * @mac_header: Link layer header
382 * @tail: Tail pointer
384 * @head: Head of buffer
385 * @data: Data head pointer
386 * @truesize: Buffer size
387 * @users: User count - see {datagram,tcp}.c
391 /* These two members must be first. */
392 struct sk_buff
*next
;
393 struct sk_buff
*prev
;
398 struct net_device
*dev
;
401 * This is the control buffer. It is free to use for every
402 * layer. Please put your private variables there. If you
403 * want to keep them across layers you have to do a skb_clone()
404 * first. This is owned by whoever has the skb queued ATM.
406 char cb
[48] __aligned(8);
408 unsigned long _skb_refdst
;
424 kmemcheck_bitfield_begin(flags1
);
435 kmemcheck_bitfield_end(flags1
);
438 void (*destructor
)(struct sk_buff
*skb
);
439 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
440 struct nf_conntrack
*nfct
;
442 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
443 struct sk_buff
*nfct_reasm
;
445 #ifdef CONFIG_BRIDGE_NETFILTER
446 struct nf_bridge_info
*nf_bridge
;
455 #ifdef CONFIG_NET_SCHED
456 __u16 tc_index
; /* traffic control index */
457 #ifdef CONFIG_NET_CLS_ACT
458 __u16 tc_verd
; /* traffic control verdict */
463 kmemcheck_bitfield_begin(flags2
);
464 #ifdef CONFIG_IPV6_NDISC_NODETYPE
465 __u8 ndisc_nodetype
:2;
469 __u8 wifi_acked_valid
:1;
472 /* 9/11 bit hole (depending on ndisc_nodetype presence) */
473 kmemcheck_bitfield_end(flags2
);
475 #ifdef CONFIG_NET_DMA
476 dma_cookie_t dma_cookie
;
478 #ifdef CONFIG_NETWORK_SECMARK
487 sk_buff_data_t transport_header
;
488 sk_buff_data_t network_header
;
489 sk_buff_data_t mac_header
;
490 /* These elements must be at the end, see alloc_skb() for details. */
495 unsigned int truesize
;
501 * Handling routines are only of interest to the kernel
503 #include <linux/slab.h>
507 * skb might have a dst pointer attached, refcounted or not.
508 * _skb_refdst low order bit is set if refcount was _not_ taken
510 #define SKB_DST_NOREF 1UL
511 #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
514 * skb_dst - returns skb dst_entry
517 * Returns skb dst_entry, regardless of reference taken or not.
519 static inline struct dst_entry
*skb_dst(const struct sk_buff
*skb
)
521 /* If refdst was not refcounted, check we still are in a
522 * rcu_read_lock section
524 WARN_ON((skb
->_skb_refdst
& SKB_DST_NOREF
) &&
525 !rcu_read_lock_held() &&
526 !rcu_read_lock_bh_held());
527 return (struct dst_entry
*)(skb
->_skb_refdst
& SKB_DST_PTRMASK
);
531 * skb_dst_set - sets skb dst
535 * Sets skb dst, assuming a reference was taken on dst and should
536 * be released by skb_dst_drop()
538 static inline void skb_dst_set(struct sk_buff
*skb
, struct dst_entry
*dst
)
540 skb
->_skb_refdst
= (unsigned long)dst
;
543 extern void skb_dst_set_noref(struct sk_buff
*skb
, struct dst_entry
*dst
);
546 * skb_dst_is_noref - Test if skb dst isn't refcounted
549 static inline bool skb_dst_is_noref(const struct sk_buff
*skb
)
551 return (skb
->_skb_refdst
& SKB_DST_NOREF
) && skb_dst(skb
);
554 static inline struct rtable
*skb_rtable(const struct sk_buff
*skb
)
556 return (struct rtable
*)skb_dst(skb
);
559 extern void kfree_skb(struct sk_buff
*skb
);
560 extern void consume_skb(struct sk_buff
*skb
);
561 extern void __kfree_skb(struct sk_buff
*skb
);
562 extern struct sk_buff
*__alloc_skb(unsigned int size
,
563 gfp_t priority
, int fclone
, int node
);
564 extern struct sk_buff
*build_skb(void *data
);
565 static inline struct sk_buff
*alloc_skb(unsigned int size
,
568 return __alloc_skb(size
, priority
, 0, NUMA_NO_NODE
);
571 static inline struct sk_buff
*alloc_skb_fclone(unsigned int size
,
574 return __alloc_skb(size
, priority
, 1, NUMA_NO_NODE
);
577 extern void skb_recycle(struct sk_buff
*skb
);
578 extern bool skb_recycle_check(struct sk_buff
*skb
, int skb_size
);
580 extern struct sk_buff
*skb_morph(struct sk_buff
*dst
, struct sk_buff
*src
);
581 extern int skb_copy_ubufs(struct sk_buff
*skb
, gfp_t gfp_mask
);
582 extern struct sk_buff
*skb_clone(struct sk_buff
*skb
,
584 extern struct sk_buff
*skb_copy(const struct sk_buff
*skb
,
586 extern struct sk_buff
*__pskb_copy(struct sk_buff
*skb
,
587 int headroom
, gfp_t gfp_mask
);
589 extern int pskb_expand_head(struct sk_buff
*skb
,
590 int nhead
, int ntail
,
592 extern struct sk_buff
*skb_realloc_headroom(struct sk_buff
*skb
,
593 unsigned int headroom
);
594 extern struct sk_buff
*skb_copy_expand(const struct sk_buff
*skb
,
595 int newheadroom
, int newtailroom
,
597 extern int skb_to_sgvec(struct sk_buff
*skb
,
598 struct scatterlist
*sg
, int offset
,
600 extern int skb_cow_data(struct sk_buff
*skb
, int tailbits
,
601 struct sk_buff
**trailer
);
602 extern int skb_pad(struct sk_buff
*skb
, int pad
);
603 #define dev_kfree_skb(a) consume_skb(a)
605 extern int skb_append_datato_frags(struct sock
*sk
, struct sk_buff
*skb
,
606 int getfrag(void *from
, char *to
, int offset
,
607 int len
,int odd
, struct sk_buff
*skb
),
608 void *from
, int length
);
610 struct skb_seq_state
{
614 __u32 stepped_offset
;
615 struct sk_buff
*root_skb
;
616 struct sk_buff
*cur_skb
;
620 extern void skb_prepare_seq_read(struct sk_buff
*skb
,
621 unsigned int from
, unsigned int to
,
622 struct skb_seq_state
*st
);
623 extern unsigned int skb_seq_read(unsigned int consumed
, const u8
**data
,
624 struct skb_seq_state
*st
);
625 extern void skb_abort_seq_read(struct skb_seq_state
*st
);
627 extern unsigned int skb_find_text(struct sk_buff
*skb
, unsigned int from
,
628 unsigned int to
, struct ts_config
*config
,
629 struct ts_state
*state
);
631 extern void __skb_get_rxhash(struct sk_buff
*skb
);
632 static inline __u32
skb_get_rxhash(struct sk_buff
*skb
)
635 __skb_get_rxhash(skb
);
640 #ifdef NET_SKBUFF_DATA_USES_OFFSET
641 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
643 return skb
->head
+ skb
->end
;
646 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
653 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
655 static inline struct skb_shared_hwtstamps
*skb_hwtstamps(struct sk_buff
*skb
)
657 return &skb_shinfo(skb
)->hwtstamps
;
661 * skb_queue_empty - check if a queue is empty
664 * Returns true if the queue is empty, false otherwise.
666 static inline int skb_queue_empty(const struct sk_buff_head
*list
)
668 return list
->next
== (struct sk_buff
*)list
;
672 * skb_queue_is_last - check if skb is the last entry in the queue
676 * Returns true if @skb is the last buffer on the list.
678 static inline bool skb_queue_is_last(const struct sk_buff_head
*list
,
679 const struct sk_buff
*skb
)
681 return skb
->next
== (struct sk_buff
*)list
;
685 * skb_queue_is_first - check if skb is the first entry in the queue
689 * Returns true if @skb is the first buffer on the list.
691 static inline bool skb_queue_is_first(const struct sk_buff_head
*list
,
692 const struct sk_buff
*skb
)
694 return skb
->prev
== (struct sk_buff
*)list
;
698 * skb_queue_next - return the next packet in the queue
700 * @skb: current buffer
702 * Return the next packet in @list after @skb. It is only valid to
703 * call this if skb_queue_is_last() evaluates to false.
705 static inline struct sk_buff
*skb_queue_next(const struct sk_buff_head
*list
,
706 const struct sk_buff
*skb
)
708 /* This BUG_ON may seem severe, but if we just return then we
709 * are going to dereference garbage.
711 BUG_ON(skb_queue_is_last(list
, skb
));
716 * skb_queue_prev - return the prev packet in the queue
718 * @skb: current buffer
720 * Return the prev packet in @list before @skb. It is only valid to
721 * call this if skb_queue_is_first() evaluates to false.
723 static inline struct sk_buff
*skb_queue_prev(const struct sk_buff_head
*list
,
724 const struct sk_buff
*skb
)
726 /* This BUG_ON may seem severe, but if we just return then we
727 * are going to dereference garbage.
729 BUG_ON(skb_queue_is_first(list
, skb
));
734 * skb_get - reference buffer
735 * @skb: buffer to reference
737 * Makes another reference to a socket buffer and returns a pointer
740 static inline struct sk_buff
*skb_get(struct sk_buff
*skb
)
742 atomic_inc(&skb
->users
);
747 * If users == 1, we are the only owner and are can avoid redundant
752 * skb_cloned - is the buffer a clone
753 * @skb: buffer to check
755 * Returns true if the buffer was generated with skb_clone() and is
756 * one of multiple shared copies of the buffer. Cloned buffers are
757 * shared data so must not be written to under normal circumstances.
759 static inline int skb_cloned(const struct sk_buff
*skb
)
761 return skb
->cloned
&&
762 (atomic_read(&skb_shinfo(skb
)->dataref
) & SKB_DATAREF_MASK
) != 1;
766 * skb_header_cloned - is the header a clone
767 * @skb: buffer to check
769 * Returns true if modifying the header part of the buffer requires
770 * the data to be copied.
772 static inline int skb_header_cloned(const struct sk_buff
*skb
)
779 dataref
= atomic_read(&skb_shinfo(skb
)->dataref
);
780 dataref
= (dataref
& SKB_DATAREF_MASK
) - (dataref
>> SKB_DATAREF_SHIFT
);
785 * skb_header_release - release reference to header
786 * @skb: buffer to operate on
788 * Drop a reference to the header part of the buffer. This is done
789 * by acquiring a payload reference. You must not read from the header
790 * part of skb->data after this.
792 static inline void skb_header_release(struct sk_buff
*skb
)
796 atomic_add(1 << SKB_DATAREF_SHIFT
, &skb_shinfo(skb
)->dataref
);
800 * skb_shared - is the buffer shared
801 * @skb: buffer to check
803 * Returns true if more than one person has a reference to this
806 static inline int skb_shared(const struct sk_buff
*skb
)
808 return atomic_read(&skb
->users
) != 1;
812 * skb_share_check - check if buffer is shared and if so clone it
813 * @skb: buffer to check
814 * @pri: priority for memory allocation
816 * If the buffer is shared the buffer is cloned and the old copy
817 * drops a reference. A new clone with a single reference is returned.
818 * If the buffer is not shared the original buffer is returned. When
819 * being called from interrupt status or with spinlocks held pri must
822 * NULL is returned on a memory allocation failure.
824 static inline struct sk_buff
*skb_share_check(struct sk_buff
*skb
,
827 might_sleep_if(pri
& __GFP_WAIT
);
828 if (skb_shared(skb
)) {
829 struct sk_buff
*nskb
= skb_clone(skb
, pri
);
837 * Copy shared buffers into a new sk_buff. We effectively do COW on
838 * packets to handle cases where we have a local reader and forward
839 * and a couple of other messy ones. The normal one is tcpdumping
840 * a packet thats being forwarded.
844 * skb_unshare - make a copy of a shared buffer
845 * @skb: buffer to check
846 * @pri: priority for memory allocation
848 * If the socket buffer is a clone then this function creates a new
849 * copy of the data, drops a reference count on the old copy and returns
850 * the new copy with the reference count at 1. If the buffer is not a clone
851 * the original buffer is returned. When called with a spinlock held or
852 * from interrupt state @pri must be %GFP_ATOMIC
854 * %NULL is returned on a memory allocation failure.
856 static inline struct sk_buff
*skb_unshare(struct sk_buff
*skb
,
859 might_sleep_if(pri
& __GFP_WAIT
);
860 if (skb_cloned(skb
)) {
861 struct sk_buff
*nskb
= skb_copy(skb
, pri
);
862 kfree_skb(skb
); /* Free our shared copy */
869 * skb_peek - peek at the head of an &sk_buff_head
870 * @list_: list to peek at
872 * Peek an &sk_buff. Unlike most other operations you _MUST_
873 * be careful with this one. A peek leaves the buffer on the
874 * list and someone else may run off with it. You must hold
875 * the appropriate locks or have a private queue to do this.
877 * Returns %NULL for an empty list or a pointer to the head element.
878 * The reference count is not incremented and the reference is therefore
879 * volatile. Use with caution.
881 static inline struct sk_buff
*skb_peek(const struct sk_buff_head
*list_
)
883 struct sk_buff
*list
= ((const struct sk_buff
*)list_
)->next
;
884 if (list
== (struct sk_buff
*)list_
)
890 * skb_peek_next - peek skb following the given one from a queue
891 * @skb: skb to start from
892 * @list_: list to peek at
894 * Returns %NULL when the end of the list is met or a pointer to the
895 * next element. The reference count is not incremented and the
896 * reference is therefore volatile. Use with caution.
898 static inline struct sk_buff
*skb_peek_next(struct sk_buff
*skb
,
899 const struct sk_buff_head
*list_
)
901 struct sk_buff
*next
= skb
->next
;
902 if (next
== (struct sk_buff
*)list_
)
908 * skb_peek_tail - peek at the tail of an &sk_buff_head
909 * @list_: list to peek at
911 * Peek an &sk_buff. Unlike most other operations you _MUST_
912 * be careful with this one. A peek leaves the buffer on the
913 * list and someone else may run off with it. You must hold
914 * the appropriate locks or have a private queue to do this.
916 * Returns %NULL for an empty list or a pointer to the tail element.
917 * The reference count is not incremented and the reference is therefore
918 * volatile. Use with caution.
920 static inline struct sk_buff
*skb_peek_tail(const struct sk_buff_head
*list_
)
922 struct sk_buff
*list
= ((const struct sk_buff
*)list_
)->prev
;
923 if (list
== (struct sk_buff
*)list_
)
929 * skb_queue_len - get queue length
930 * @list_: list to measure
932 * Return the length of an &sk_buff queue.
934 static inline __u32
skb_queue_len(const struct sk_buff_head
*list_
)
940 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
941 * @list: queue to initialize
943 * This initializes only the list and queue length aspects of
944 * an sk_buff_head object. This allows to initialize the list
945 * aspects of an sk_buff_head without reinitializing things like
946 * the spinlock. It can also be used for on-stack sk_buff_head
947 * objects where the spinlock is known to not be used.
949 static inline void __skb_queue_head_init(struct sk_buff_head
*list
)
951 list
->prev
= list
->next
= (struct sk_buff
*)list
;
956 * This function creates a split out lock class for each invocation;
957 * this is needed for now since a whole lot of users of the skb-queue
958 * infrastructure in drivers have different locking usage (in hardirq)
959 * than the networking core (in softirq only). In the long run either the
960 * network layer or drivers should need annotation to consolidate the
961 * main types of usage into 3 classes.
963 static inline void skb_queue_head_init(struct sk_buff_head
*list
)
965 spin_lock_init(&list
->lock
);
966 __skb_queue_head_init(list
);
969 static inline void skb_queue_head_init_class(struct sk_buff_head
*list
,
970 struct lock_class_key
*class)
972 skb_queue_head_init(list
);
973 lockdep_set_class(&list
->lock
, class);
977 * Insert an sk_buff on a list.
979 * The "__skb_xxxx()" functions are the non-atomic ones that
980 * can only be called with interrupts disabled.
982 extern void skb_insert(struct sk_buff
*old
, struct sk_buff
*newsk
, struct sk_buff_head
*list
);
983 static inline void __skb_insert(struct sk_buff
*newsk
,
984 struct sk_buff
*prev
, struct sk_buff
*next
,
985 struct sk_buff_head
*list
)
989 next
->prev
= prev
->next
= newsk
;
993 static inline void __skb_queue_splice(const struct sk_buff_head
*list
,
994 struct sk_buff
*prev
,
995 struct sk_buff
*next
)
997 struct sk_buff
*first
= list
->next
;
998 struct sk_buff
*last
= list
->prev
;
1008 * skb_queue_splice - join two skb lists, this is designed for stacks
1009 * @list: the new list to add
1010 * @head: the place to add it in the first list
1012 static inline void skb_queue_splice(const struct sk_buff_head
*list
,
1013 struct sk_buff_head
*head
)
1015 if (!skb_queue_empty(list
)) {
1016 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1017 head
->qlen
+= list
->qlen
;
1022 * skb_queue_splice - join two skb lists and reinitialise the emptied list
1023 * @list: the new list to add
1024 * @head: the place to add it in the first list
1026 * The list at @list is reinitialised
1028 static inline void skb_queue_splice_init(struct sk_buff_head
*list
,
1029 struct sk_buff_head
*head
)
1031 if (!skb_queue_empty(list
)) {
1032 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1033 head
->qlen
+= list
->qlen
;
1034 __skb_queue_head_init(list
);
1039 * skb_queue_splice_tail - join two skb lists, each list being a queue
1040 * @list: the new list to add
1041 * @head: the place to add it in the first list
1043 static inline void skb_queue_splice_tail(const struct sk_buff_head
*list
,
1044 struct sk_buff_head
*head
)
1046 if (!skb_queue_empty(list
)) {
1047 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1048 head
->qlen
+= list
->qlen
;
1053 * skb_queue_splice_tail - join two skb lists and reinitialise the emptied list
1054 * @list: the new list to add
1055 * @head: the place to add it in the first list
1057 * Each of the lists is a queue.
1058 * The list at @list is reinitialised
1060 static inline void skb_queue_splice_tail_init(struct sk_buff_head
*list
,
1061 struct sk_buff_head
*head
)
1063 if (!skb_queue_empty(list
)) {
1064 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1065 head
->qlen
+= list
->qlen
;
1066 __skb_queue_head_init(list
);
1071 * __skb_queue_after - queue a buffer at the list head
1072 * @list: list to use
1073 * @prev: place after this buffer
1074 * @newsk: buffer to queue
1076 * Queue a buffer int the middle of a list. This function takes no locks
1077 * and you must therefore hold required locks before calling it.
1079 * A buffer cannot be placed on two lists at the same time.
1081 static inline void __skb_queue_after(struct sk_buff_head
*list
,
1082 struct sk_buff
*prev
,
1083 struct sk_buff
*newsk
)
1085 __skb_insert(newsk
, prev
, prev
->next
, list
);
1088 extern void skb_append(struct sk_buff
*old
, struct sk_buff
*newsk
,
1089 struct sk_buff_head
*list
);
1091 static inline void __skb_queue_before(struct sk_buff_head
*list
,
1092 struct sk_buff
*next
,
1093 struct sk_buff
*newsk
)
1095 __skb_insert(newsk
, next
->prev
, next
, list
);
1099 * __skb_queue_head - queue a buffer at the list head
1100 * @list: list to use
1101 * @newsk: buffer to queue
1103 * Queue a buffer at the start of a list. This function takes no locks
1104 * and you must therefore hold required locks before calling it.
1106 * A buffer cannot be placed on two lists at the same time.
1108 extern void skb_queue_head(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1109 static inline void __skb_queue_head(struct sk_buff_head
*list
,
1110 struct sk_buff
*newsk
)
1112 __skb_queue_after(list
, (struct sk_buff
*)list
, newsk
);
1116 * __skb_queue_tail - queue a buffer at the list tail
1117 * @list: list to use
1118 * @newsk: buffer to queue
1120 * Queue a buffer at the end of a list. This function takes no locks
1121 * and you must therefore hold required locks before calling it.
1123 * A buffer cannot be placed on two lists at the same time.
1125 extern void skb_queue_tail(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1126 static inline void __skb_queue_tail(struct sk_buff_head
*list
,
1127 struct sk_buff
*newsk
)
1129 __skb_queue_before(list
, (struct sk_buff
*)list
, newsk
);
1133 * remove sk_buff from list. _Must_ be called atomically, and with
1136 extern void skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
);
1137 static inline void __skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
)
1139 struct sk_buff
*next
, *prev
;
1144 skb
->next
= skb
->prev
= NULL
;
1150 * __skb_dequeue - remove from the head of the queue
1151 * @list: list to dequeue from
1153 * Remove the head of the list. This function does not take any locks
1154 * so must be used with appropriate locks held only. The head item is
1155 * returned or %NULL if the list is empty.
1157 extern struct sk_buff
*skb_dequeue(struct sk_buff_head
*list
);
1158 static inline struct sk_buff
*__skb_dequeue(struct sk_buff_head
*list
)
1160 struct sk_buff
*skb
= skb_peek(list
);
1162 __skb_unlink(skb
, list
);
1167 * __skb_dequeue_tail - remove from the tail of the queue
1168 * @list: list to dequeue from
1170 * Remove the tail of the list. This function does not take any locks
1171 * so must be used with appropriate locks held only. The tail item is
1172 * returned or %NULL if the list is empty.
1174 extern struct sk_buff
*skb_dequeue_tail(struct sk_buff_head
*list
);
1175 static inline struct sk_buff
*__skb_dequeue_tail(struct sk_buff_head
*list
)
1177 struct sk_buff
*skb
= skb_peek_tail(list
);
1179 __skb_unlink(skb
, list
);
1184 static inline bool skb_is_nonlinear(const struct sk_buff
*skb
)
1186 return skb
->data_len
;
1189 static inline unsigned int skb_headlen(const struct sk_buff
*skb
)
1191 return skb
->len
- skb
->data_len
;
1194 static inline int skb_pagelen(const struct sk_buff
*skb
)
1198 for (i
= (int)skb_shinfo(skb
)->nr_frags
- 1; i
>= 0; i
--)
1199 len
+= skb_frag_size(&skb_shinfo(skb
)->frags
[i
]);
1200 return len
+ skb_headlen(skb
);
1204 * __skb_fill_page_desc - initialise a paged fragment in an skb
1205 * @skb: buffer containing fragment to be initialised
1206 * @i: paged fragment index to initialise
1207 * @page: the page to use for this fragment
1208 * @off: the offset to the data with @page
1209 * @size: the length of the data
1211 * Initialises the @i'th fragment of @skb to point to &size bytes at
1212 * offset @off within @page.
1214 * Does not take any additional reference on the fragment.
1216 static inline void __skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1217 struct page
*page
, int off
, int size
)
1219 skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
];
1221 frag
->page
.p
= page
;
1222 frag
->page_offset
= off
;
1223 skb_frag_size_set(frag
, size
);
1227 * skb_fill_page_desc - initialise a paged fragment in an skb
1228 * @skb: buffer containing fragment to be initialised
1229 * @i: paged fragment index to initialise
1230 * @page: the page to use for this fragment
1231 * @off: the offset to the data with @page
1232 * @size: the length of the data
1234 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
1235 * @skb to point to &size bytes at offset @off within @page. In
1236 * addition updates @skb such that @i is the last fragment.
1238 * Does not take any additional reference on the fragment.
1240 static inline void skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1241 struct page
*page
, int off
, int size
)
1243 __skb_fill_page_desc(skb
, i
, page
, off
, size
);
1244 skb_shinfo(skb
)->nr_frags
= i
+ 1;
1247 extern void skb_add_rx_frag(struct sk_buff
*skb
, int i
, struct page
*page
,
1248 int off
, int size
, unsigned int truesize
);
1250 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
1251 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb))
1252 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
1254 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1255 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1257 return skb
->head
+ skb
->tail
;
1260 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1262 skb
->tail
= skb
->data
- skb
->head
;
1265 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1267 skb_reset_tail_pointer(skb
);
1268 skb
->tail
+= offset
;
1270 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1271 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1276 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1278 skb
->tail
= skb
->data
;
1281 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1283 skb
->tail
= skb
->data
+ offset
;
1286 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1289 * Add data to an sk_buff
1291 extern unsigned char *skb_put(struct sk_buff
*skb
, unsigned int len
);
1292 static inline unsigned char *__skb_put(struct sk_buff
*skb
, unsigned int len
)
1294 unsigned char *tmp
= skb_tail_pointer(skb
);
1295 SKB_LINEAR_ASSERT(skb
);
1301 extern unsigned char *skb_push(struct sk_buff
*skb
, unsigned int len
);
1302 static inline unsigned char *__skb_push(struct sk_buff
*skb
, unsigned int len
)
1309 extern unsigned char *skb_pull(struct sk_buff
*skb
, unsigned int len
);
1310 static inline unsigned char *__skb_pull(struct sk_buff
*skb
, unsigned int len
)
1313 BUG_ON(skb
->len
< skb
->data_len
);
1314 return skb
->data
+= len
;
1317 static inline unsigned char *skb_pull_inline(struct sk_buff
*skb
, unsigned int len
)
1319 return unlikely(len
> skb
->len
) ? NULL
: __skb_pull(skb
, len
);
1322 extern unsigned char *__pskb_pull_tail(struct sk_buff
*skb
, int delta
);
1324 static inline unsigned char *__pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1326 if (len
> skb_headlen(skb
) &&
1327 !__pskb_pull_tail(skb
, len
- skb_headlen(skb
)))
1330 return skb
->data
+= len
;
1333 static inline unsigned char *pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1335 return unlikely(len
> skb
->len
) ? NULL
: __pskb_pull(skb
, len
);
1338 static inline int pskb_may_pull(struct sk_buff
*skb
, unsigned int len
)
1340 if (likely(len
<= skb_headlen(skb
)))
1342 if (unlikely(len
> skb
->len
))
1344 return __pskb_pull_tail(skb
, len
- skb_headlen(skb
)) != NULL
;
1348 * skb_headroom - bytes at buffer head
1349 * @skb: buffer to check
1351 * Return the number of bytes of free space at the head of an &sk_buff.
1353 static inline unsigned int skb_headroom(const struct sk_buff
*skb
)
1355 return skb
->data
- skb
->head
;
1359 * skb_tailroom - bytes at buffer end
1360 * @skb: buffer to check
1362 * Return the number of bytes of free space at the tail of an sk_buff
1364 static inline int skb_tailroom(const struct sk_buff
*skb
)
1366 return skb_is_nonlinear(skb
) ? 0 : skb
->end
- skb
->tail
;
1370 * skb_availroom - bytes at buffer end
1371 * @skb: buffer to check
1373 * Return the number of bytes of free space at the tail of an sk_buff
1374 * allocated by sk_stream_alloc()
1376 static inline int skb_availroom(const struct sk_buff
*skb
)
1378 return skb_is_nonlinear(skb
) ? 0 : skb
->avail_size
- skb
->len
;
1382 * skb_reserve - adjust headroom
1383 * @skb: buffer to alter
1384 * @len: bytes to move
1386 * Increase the headroom of an empty &sk_buff by reducing the tail
1387 * room. This is only allowed for an empty buffer.
1389 static inline void skb_reserve(struct sk_buff
*skb
, int len
)
1395 static inline void skb_reset_mac_len(struct sk_buff
*skb
)
1397 skb
->mac_len
= skb
->network_header
- skb
->mac_header
;
1400 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1401 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1403 return skb
->head
+ skb
->transport_header
;
1406 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1408 skb
->transport_header
= skb
->data
- skb
->head
;
1411 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1414 skb_reset_transport_header(skb
);
1415 skb
->transport_header
+= offset
;
1418 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1420 return skb
->head
+ skb
->network_header
;
1423 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1425 skb
->network_header
= skb
->data
- skb
->head
;
1428 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1430 skb_reset_network_header(skb
);
1431 skb
->network_header
+= offset
;
1434 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1436 return skb
->head
+ skb
->mac_header
;
1439 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1441 return skb
->mac_header
!= ~0U;
1444 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1446 skb
->mac_header
= skb
->data
- skb
->head
;
1449 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1451 skb_reset_mac_header(skb
);
1452 skb
->mac_header
+= offset
;
1455 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1457 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1459 return skb
->transport_header
;
1462 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1464 skb
->transport_header
= skb
->data
;
1467 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1470 skb
->transport_header
= skb
->data
+ offset
;
1473 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1475 return skb
->network_header
;
1478 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1480 skb
->network_header
= skb
->data
;
1483 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1485 skb
->network_header
= skb
->data
+ offset
;
1488 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1490 return skb
->mac_header
;
1493 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1495 return skb
->mac_header
!= NULL
;
1498 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1500 skb
->mac_header
= skb
->data
;
1503 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1505 skb
->mac_header
= skb
->data
+ offset
;
1507 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1509 static inline void skb_mac_header_rebuild(struct sk_buff
*skb
)
1511 if (skb_mac_header_was_set(skb
)) {
1512 const unsigned char *old_mac
= skb_mac_header(skb
);
1514 skb_set_mac_header(skb
, -skb
->mac_len
);
1515 memmove(skb_mac_header(skb
), old_mac
, skb
->mac_len
);
1519 static inline int skb_checksum_start_offset(const struct sk_buff
*skb
)
1521 return skb
->csum_start
- skb_headroom(skb
);
1524 static inline int skb_transport_offset(const struct sk_buff
*skb
)
1526 return skb_transport_header(skb
) - skb
->data
;
1529 static inline u32
skb_network_header_len(const struct sk_buff
*skb
)
1531 return skb
->transport_header
- skb
->network_header
;
1534 static inline int skb_network_offset(const struct sk_buff
*skb
)
1536 return skb_network_header(skb
) - skb
->data
;
1539 static inline int pskb_network_may_pull(struct sk_buff
*skb
, unsigned int len
)
1541 return pskb_may_pull(skb
, skb_network_offset(skb
) + len
);
1545 * CPUs often take a performance hit when accessing unaligned memory
1546 * locations. The actual performance hit varies, it can be small if the
1547 * hardware handles it or large if we have to take an exception and fix it
1550 * Since an ethernet header is 14 bytes network drivers often end up with
1551 * the IP header at an unaligned offset. The IP header can be aligned by
1552 * shifting the start of the packet by 2 bytes. Drivers should do this
1555 * skb_reserve(skb, NET_IP_ALIGN);
1557 * The downside to this alignment of the IP header is that the DMA is now
1558 * unaligned. On some architectures the cost of an unaligned DMA is high
1559 * and this cost outweighs the gains made by aligning the IP header.
1561 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1564 #ifndef NET_IP_ALIGN
1565 #define NET_IP_ALIGN 2
1569 * The networking layer reserves some headroom in skb data (via
1570 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1571 * the header has to grow. In the default case, if the header has to grow
1572 * 32 bytes or less we avoid the reallocation.
1574 * Unfortunately this headroom changes the DMA alignment of the resulting
1575 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1576 * on some architectures. An architecture can override this value,
1577 * perhaps setting it to a cacheline in size (since that will maintain
1578 * cacheline alignment of the DMA). It must be a power of 2.
1580 * Various parts of the networking layer expect at least 32 bytes of
1581 * headroom, you should not reduce this.
1583 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
1584 * to reduce average number of cache lines per packet.
1585 * get_rps_cpus() for example only access one 64 bytes aligned block :
1586 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
1589 #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
1592 extern int ___pskb_trim(struct sk_buff
*skb
, unsigned int len
);
1594 static inline void __skb_trim(struct sk_buff
*skb
, unsigned int len
)
1596 if (unlikely(skb_is_nonlinear(skb
))) {
1601 skb_set_tail_pointer(skb
, len
);
1604 extern void skb_trim(struct sk_buff
*skb
, unsigned int len
);
1606 static inline int __pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1609 return ___pskb_trim(skb
, len
);
1610 __skb_trim(skb
, len
);
1614 static inline int pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1616 return (len
< skb
->len
) ? __pskb_trim(skb
, len
) : 0;
1620 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1621 * @skb: buffer to alter
1624 * This is identical to pskb_trim except that the caller knows that
1625 * the skb is not cloned so we should never get an error due to out-
1628 static inline void pskb_trim_unique(struct sk_buff
*skb
, unsigned int len
)
1630 int err
= pskb_trim(skb
, len
);
1635 * skb_orphan - orphan a buffer
1636 * @skb: buffer to orphan
1638 * If a buffer currently has an owner then we call the owner's
1639 * destructor function and make the @skb unowned. The buffer continues
1640 * to exist but is no longer charged to its former owner.
1642 static inline void skb_orphan(struct sk_buff
*skb
)
1644 if (skb
->destructor
)
1645 skb
->destructor(skb
);
1646 skb
->destructor
= NULL
;
1651 * __skb_queue_purge - empty a list
1652 * @list: list to empty
1654 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1655 * the list and one reference dropped. This function does not take the
1656 * list lock and the caller must hold the relevant locks to use it.
1658 extern void skb_queue_purge(struct sk_buff_head
*list
);
1659 static inline void __skb_queue_purge(struct sk_buff_head
*list
)
1661 struct sk_buff
*skb
;
1662 while ((skb
= __skb_dequeue(list
)) != NULL
)
1667 * __dev_alloc_skb - allocate an skbuff for receiving
1668 * @length: length to allocate
1669 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1671 * Allocate a new &sk_buff and assign it a usage count of one. The
1672 * buffer has unspecified headroom built in. Users should allocate
1673 * the headroom they think they need without accounting for the
1674 * built in space. The built in space is used for optimisations.
1676 * %NULL is returned if there is no free memory.
1678 static inline struct sk_buff
*__dev_alloc_skb(unsigned int length
,
1681 struct sk_buff
*skb
= alloc_skb(length
+ NET_SKB_PAD
, gfp_mask
);
1683 skb_reserve(skb
, NET_SKB_PAD
);
1687 extern struct sk_buff
*dev_alloc_skb(unsigned int length
);
1689 extern struct sk_buff
*__netdev_alloc_skb(struct net_device
*dev
,
1690 unsigned int length
, gfp_t gfp_mask
);
1693 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1694 * @dev: network device to receive on
1695 * @length: length to allocate
1697 * Allocate a new &sk_buff and assign it a usage count of one. The
1698 * buffer has unspecified headroom built in. Users should allocate
1699 * the headroom they think they need without accounting for the
1700 * built in space. The built in space is used for optimisations.
1702 * %NULL is returned if there is no free memory. Although this function
1703 * allocates memory it can be called from an interrupt.
1705 static inline struct sk_buff
*netdev_alloc_skb(struct net_device
*dev
,
1706 unsigned int length
)
1708 return __netdev_alloc_skb(dev
, length
, GFP_ATOMIC
);
1711 static inline struct sk_buff
*__netdev_alloc_skb_ip_align(struct net_device
*dev
,
1712 unsigned int length
, gfp_t gfp
)
1714 struct sk_buff
*skb
= __netdev_alloc_skb(dev
, length
+ NET_IP_ALIGN
, gfp
);
1716 if (NET_IP_ALIGN
&& skb
)
1717 skb_reserve(skb
, NET_IP_ALIGN
);
1721 static inline struct sk_buff
*netdev_alloc_skb_ip_align(struct net_device
*dev
,
1722 unsigned int length
)
1724 return __netdev_alloc_skb_ip_align(dev
, length
, GFP_ATOMIC
);
1728 * skb_frag_page - retrieve the page refered to by a paged fragment
1729 * @frag: the paged fragment
1731 * Returns the &struct page associated with @frag.
1733 static inline struct page
*skb_frag_page(const skb_frag_t
*frag
)
1735 return frag
->page
.p
;
1739 * __skb_frag_ref - take an addition reference on a paged fragment.
1740 * @frag: the paged fragment
1742 * Takes an additional reference on the paged fragment @frag.
1744 static inline void __skb_frag_ref(skb_frag_t
*frag
)
1746 get_page(skb_frag_page(frag
));
1750 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
1752 * @f: the fragment offset.
1754 * Takes an additional reference on the @f'th paged fragment of @skb.
1756 static inline void skb_frag_ref(struct sk_buff
*skb
, int f
)
1758 __skb_frag_ref(&skb_shinfo(skb
)->frags
[f
]);
1762 * __skb_frag_unref - release a reference on a paged fragment.
1763 * @frag: the paged fragment
1765 * Releases a reference on the paged fragment @frag.
1767 static inline void __skb_frag_unref(skb_frag_t
*frag
)
1769 put_page(skb_frag_page(frag
));
1773 * skb_frag_unref - release a reference on a paged fragment of an skb.
1775 * @f: the fragment offset
1777 * Releases a reference on the @f'th paged fragment of @skb.
1779 static inline void skb_frag_unref(struct sk_buff
*skb
, int f
)
1781 __skb_frag_unref(&skb_shinfo(skb
)->frags
[f
]);
1785 * skb_frag_address - gets the address of the data contained in a paged fragment
1786 * @frag: the paged fragment buffer
1788 * Returns the address of the data within @frag. The page must already
1791 static inline void *skb_frag_address(const skb_frag_t
*frag
)
1793 return page_address(skb_frag_page(frag
)) + frag
->page_offset
;
1797 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
1798 * @frag: the paged fragment buffer
1800 * Returns the address of the data within @frag. Checks that the page
1801 * is mapped and returns %NULL otherwise.
1803 static inline void *skb_frag_address_safe(const skb_frag_t
*frag
)
1805 void *ptr
= page_address(skb_frag_page(frag
));
1809 return ptr
+ frag
->page_offset
;
1813 * __skb_frag_set_page - sets the page contained in a paged fragment
1814 * @frag: the paged fragment
1815 * @page: the page to set
1817 * Sets the fragment @frag to contain @page.
1819 static inline void __skb_frag_set_page(skb_frag_t
*frag
, struct page
*page
)
1821 frag
->page
.p
= page
;
1825 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
1827 * @f: the fragment offset
1828 * @page: the page to set
1830 * Sets the @f'th fragment of @skb to contain @page.
1832 static inline void skb_frag_set_page(struct sk_buff
*skb
, int f
,
1835 __skb_frag_set_page(&skb_shinfo(skb
)->frags
[f
], page
);
1839 * skb_frag_dma_map - maps a paged fragment via the DMA API
1840 * @dev: the device to map the fragment to
1841 * @frag: the paged fragment to map
1842 * @offset: the offset within the fragment (starting at the
1843 * fragment's own offset)
1844 * @size: the number of bytes to map
1845 * @dir: the direction of the mapping (%PCI_DMA_*)
1847 * Maps the page associated with @frag to @device.
1849 static inline dma_addr_t
skb_frag_dma_map(struct device
*dev
,
1850 const skb_frag_t
*frag
,
1851 size_t offset
, size_t size
,
1852 enum dma_data_direction dir
)
1854 return dma_map_page(dev
, skb_frag_page(frag
),
1855 frag
->page_offset
+ offset
, size
, dir
);
1858 static inline struct sk_buff
*pskb_copy(struct sk_buff
*skb
,
1861 return __pskb_copy(skb
, skb_headroom(skb
), gfp_mask
);
1865 * skb_clone_writable - is the header of a clone writable
1866 * @skb: buffer to check
1867 * @len: length up to which to write
1869 * Returns true if modifying the header part of the cloned buffer
1870 * does not requires the data to be copied.
1872 static inline int skb_clone_writable(const struct sk_buff
*skb
, unsigned int len
)
1874 return !skb_header_cloned(skb
) &&
1875 skb_headroom(skb
) + len
<= skb
->hdr_len
;
1878 static inline int __skb_cow(struct sk_buff
*skb
, unsigned int headroom
,
1883 if (headroom
< NET_SKB_PAD
)
1884 headroom
= NET_SKB_PAD
;
1885 if (headroom
> skb_headroom(skb
))
1886 delta
= headroom
- skb_headroom(skb
);
1888 if (delta
|| cloned
)
1889 return pskb_expand_head(skb
, ALIGN(delta
, NET_SKB_PAD
), 0,
1895 * skb_cow - copy header of skb when it is required
1896 * @skb: buffer to cow
1897 * @headroom: needed headroom
1899 * If the skb passed lacks sufficient headroom or its data part
1900 * is shared, data is reallocated. If reallocation fails, an error
1901 * is returned and original skb is not changed.
1903 * The result is skb with writable area skb->head...skb->tail
1904 * and at least @headroom of space at head.
1906 static inline int skb_cow(struct sk_buff
*skb
, unsigned int headroom
)
1908 return __skb_cow(skb
, headroom
, skb_cloned(skb
));
1912 * skb_cow_head - skb_cow but only making the head writable
1913 * @skb: buffer to cow
1914 * @headroom: needed headroom
1916 * This function is identical to skb_cow except that we replace the
1917 * skb_cloned check by skb_header_cloned. It should be used when
1918 * you only need to push on some header and do not need to modify
1921 static inline int skb_cow_head(struct sk_buff
*skb
, unsigned int headroom
)
1923 return __skb_cow(skb
, headroom
, skb_header_cloned(skb
));
1927 * skb_padto - pad an skbuff up to a minimal size
1928 * @skb: buffer to pad
1929 * @len: minimal length
1931 * Pads up a buffer to ensure the trailing bytes exist and are
1932 * blanked. If the buffer already contains sufficient data it
1933 * is untouched. Otherwise it is extended. Returns zero on
1934 * success. The skb is freed on error.
1937 static inline int skb_padto(struct sk_buff
*skb
, unsigned int len
)
1939 unsigned int size
= skb
->len
;
1940 if (likely(size
>= len
))
1942 return skb_pad(skb
, len
- size
);
1945 static inline int skb_add_data(struct sk_buff
*skb
,
1946 char __user
*from
, int copy
)
1948 const int off
= skb
->len
;
1950 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1952 __wsum csum
= csum_and_copy_from_user(from
, skb_put(skb
, copy
),
1955 skb
->csum
= csum_block_add(skb
->csum
, csum
, off
);
1958 } else if (!copy_from_user(skb_put(skb
, copy
), from
, copy
))
1961 __skb_trim(skb
, off
);
1965 static inline int skb_can_coalesce(struct sk_buff
*skb
, int i
,
1966 const struct page
*page
, int off
)
1969 const struct skb_frag_struct
*frag
= &skb_shinfo(skb
)->frags
[i
- 1];
1971 return page
== skb_frag_page(frag
) &&
1972 off
== frag
->page_offset
+ skb_frag_size(frag
);
1977 static inline int __skb_linearize(struct sk_buff
*skb
)
1979 return __pskb_pull_tail(skb
, skb
->data_len
) ? 0 : -ENOMEM
;
1983 * skb_linearize - convert paged skb to linear one
1984 * @skb: buffer to linarize
1986 * If there is no free memory -ENOMEM is returned, otherwise zero
1987 * is returned and the old skb data released.
1989 static inline int skb_linearize(struct sk_buff
*skb
)
1991 return skb_is_nonlinear(skb
) ? __skb_linearize(skb
) : 0;
1995 * skb_linearize_cow - make sure skb is linear and writable
1996 * @skb: buffer to process
1998 * If there is no free memory -ENOMEM is returned, otherwise zero
1999 * is returned and the old skb data released.
2001 static inline int skb_linearize_cow(struct sk_buff
*skb
)
2003 return skb_is_nonlinear(skb
) || skb_cloned(skb
) ?
2004 __skb_linearize(skb
) : 0;
2008 * skb_postpull_rcsum - update checksum for received skb after pull
2009 * @skb: buffer to update
2010 * @start: start of data before pull
2011 * @len: length of data pulled
2013 * After doing a pull on a received packet, you need to call this to
2014 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
2015 * CHECKSUM_NONE so that it can be recomputed from scratch.
2018 static inline void skb_postpull_rcsum(struct sk_buff
*skb
,
2019 const void *start
, unsigned int len
)
2021 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2022 skb
->csum
= csum_sub(skb
->csum
, csum_partial(start
, len
, 0));
2025 unsigned char *skb_pull_rcsum(struct sk_buff
*skb
, unsigned int len
);
2028 * pskb_trim_rcsum - trim received skb and update checksum
2029 * @skb: buffer to trim
2032 * This is exactly the same as pskb_trim except that it ensures the
2033 * checksum of received packets are still valid after the operation.
2036 static inline int pskb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
2038 if (likely(len
>= skb
->len
))
2040 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2041 skb
->ip_summed
= CHECKSUM_NONE
;
2042 return __pskb_trim(skb
, len
);
2045 #define skb_queue_walk(queue, skb) \
2046 for (skb = (queue)->next; \
2047 skb != (struct sk_buff *)(queue); \
2050 #define skb_queue_walk_safe(queue, skb, tmp) \
2051 for (skb = (queue)->next, tmp = skb->next; \
2052 skb != (struct sk_buff *)(queue); \
2053 skb = tmp, tmp = skb->next)
2055 #define skb_queue_walk_from(queue, skb) \
2056 for (; skb != (struct sk_buff *)(queue); \
2059 #define skb_queue_walk_from_safe(queue, skb, tmp) \
2060 for (tmp = skb->next; \
2061 skb != (struct sk_buff *)(queue); \
2062 skb = tmp, tmp = skb->next)
2064 #define skb_queue_reverse_walk(queue, skb) \
2065 for (skb = (queue)->prev; \
2066 skb != (struct sk_buff *)(queue); \
2069 #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
2070 for (skb = (queue)->prev, tmp = skb->prev; \
2071 skb != (struct sk_buff *)(queue); \
2072 skb = tmp, tmp = skb->prev)
2074 #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
2075 for (tmp = skb->prev; \
2076 skb != (struct sk_buff *)(queue); \
2077 skb = tmp, tmp = skb->prev)
2079 static inline bool skb_has_frag_list(const struct sk_buff
*skb
)
2081 return skb_shinfo(skb
)->frag_list
!= NULL
;
2084 static inline void skb_frag_list_init(struct sk_buff
*skb
)
2086 skb_shinfo(skb
)->frag_list
= NULL
;
2089 static inline void skb_frag_add_head(struct sk_buff
*skb
, struct sk_buff
*frag
)
2091 frag
->next
= skb_shinfo(skb
)->frag_list
;
2092 skb_shinfo(skb
)->frag_list
= frag
;
2095 #define skb_walk_frags(skb, iter) \
2096 for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
2098 extern struct sk_buff
*__skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2099 int *peeked
, int *off
, int *err
);
2100 extern struct sk_buff
*skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2101 int noblock
, int *err
);
2102 extern unsigned int datagram_poll(struct file
*file
, struct socket
*sock
,
2103 struct poll_table_struct
*wait
);
2104 extern int skb_copy_datagram_iovec(const struct sk_buff
*from
,
2105 int offset
, struct iovec
*to
,
2107 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff
*skb
,
2110 extern int skb_copy_datagram_from_iovec(struct sk_buff
*skb
,
2112 const struct iovec
*from
,
2115 extern int skb_copy_datagram_const_iovec(const struct sk_buff
*from
,
2117 const struct iovec
*to
,
2120 extern void skb_free_datagram(struct sock
*sk
, struct sk_buff
*skb
);
2121 extern void skb_free_datagram_locked(struct sock
*sk
,
2122 struct sk_buff
*skb
);
2123 extern int skb_kill_datagram(struct sock
*sk
, struct sk_buff
*skb
,
2124 unsigned int flags
);
2125 extern __wsum
skb_checksum(const struct sk_buff
*skb
, int offset
,
2126 int len
, __wsum csum
);
2127 extern int skb_copy_bits(const struct sk_buff
*skb
, int offset
,
2129 extern int skb_store_bits(struct sk_buff
*skb
, int offset
,
2130 const void *from
, int len
);
2131 extern __wsum
skb_copy_and_csum_bits(const struct sk_buff
*skb
,
2132 int offset
, u8
*to
, int len
,
2134 extern int skb_splice_bits(struct sk_buff
*skb
,
2135 unsigned int offset
,
2136 struct pipe_inode_info
*pipe
,
2138 unsigned int flags
);
2139 extern void skb_copy_and_csum_dev(const struct sk_buff
*skb
, u8
*to
);
2140 extern void skb_split(struct sk_buff
*skb
,
2141 struct sk_buff
*skb1
, const u32 len
);
2142 extern int skb_shift(struct sk_buff
*tgt
, struct sk_buff
*skb
,
2145 extern struct sk_buff
*skb_segment(struct sk_buff
*skb
,
2146 netdev_features_t features
);
2148 static inline void *skb_header_pointer(const struct sk_buff
*skb
, int offset
,
2149 int len
, void *buffer
)
2151 int hlen
= skb_headlen(skb
);
2153 if (hlen
- offset
>= len
)
2154 return skb
->data
+ offset
;
2156 if (skb_copy_bits(skb
, offset
, buffer
, len
) < 0)
2162 static inline void skb_copy_from_linear_data(const struct sk_buff
*skb
,
2164 const unsigned int len
)
2166 memcpy(to
, skb
->data
, len
);
2169 static inline void skb_copy_from_linear_data_offset(const struct sk_buff
*skb
,
2170 const int offset
, void *to
,
2171 const unsigned int len
)
2173 memcpy(to
, skb
->data
+ offset
, len
);
2176 static inline void skb_copy_to_linear_data(struct sk_buff
*skb
,
2178 const unsigned int len
)
2180 memcpy(skb
->data
, from
, len
);
2183 static inline void skb_copy_to_linear_data_offset(struct sk_buff
*skb
,
2186 const unsigned int len
)
2188 memcpy(skb
->data
+ offset
, from
, len
);
2191 extern void skb_init(void);
2193 static inline ktime_t
skb_get_ktime(const struct sk_buff
*skb
)
2199 * skb_get_timestamp - get timestamp from a skb
2200 * @skb: skb to get stamp from
2201 * @stamp: pointer to struct timeval to store stamp in
2203 * Timestamps are stored in the skb as offsets to a base timestamp.
2204 * This function converts the offset back to a struct timeval and stores
2207 static inline void skb_get_timestamp(const struct sk_buff
*skb
,
2208 struct timeval
*stamp
)
2210 *stamp
= ktime_to_timeval(skb
->tstamp
);
2213 static inline void skb_get_timestampns(const struct sk_buff
*skb
,
2214 struct timespec
*stamp
)
2216 *stamp
= ktime_to_timespec(skb
->tstamp
);
2219 static inline void __net_timestamp(struct sk_buff
*skb
)
2221 skb
->tstamp
= ktime_get_real();
2224 static inline ktime_t
net_timedelta(ktime_t t
)
2226 return ktime_sub(ktime_get_real(), t
);
2229 static inline ktime_t
net_invalid_timestamp(void)
2231 return ktime_set(0, 0);
2234 extern void skb_timestamping_init(void);
2236 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
2238 extern void skb_clone_tx_timestamp(struct sk_buff
*skb
);
2239 extern bool skb_defer_rx_timestamp(struct sk_buff
*skb
);
2241 #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
2243 static inline void skb_clone_tx_timestamp(struct sk_buff
*skb
)
2247 static inline bool skb_defer_rx_timestamp(struct sk_buff
*skb
)
2252 #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
2255 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
2257 * PHY drivers may accept clones of transmitted packets for
2258 * timestamping via their phy_driver.txtstamp method. These drivers
2259 * must call this function to return the skb back to the stack, with
2260 * or without a timestamp.
2262 * @skb: clone of the the original outgoing packet
2263 * @hwtstamps: hardware time stamps, may be NULL if not available
2266 void skb_complete_tx_timestamp(struct sk_buff
*skb
,
2267 struct skb_shared_hwtstamps
*hwtstamps
);
2270 * skb_tstamp_tx - queue clone of skb with send time stamps
2271 * @orig_skb: the original outgoing packet
2272 * @hwtstamps: hardware time stamps, may be NULL if not available
2274 * If the skb has a socket associated, then this function clones the
2275 * skb (thus sharing the actual data and optional structures), stores
2276 * the optional hardware time stamping information (if non NULL) or
2277 * generates a software time stamp (otherwise), then queues the clone
2278 * to the error queue of the socket. Errors are silently ignored.
2280 extern void skb_tstamp_tx(struct sk_buff
*orig_skb
,
2281 struct skb_shared_hwtstamps
*hwtstamps
);
2283 static inline void sw_tx_timestamp(struct sk_buff
*skb
)
2285 if (skb_shinfo(skb
)->tx_flags
& SKBTX_SW_TSTAMP
&&
2286 !(skb_shinfo(skb
)->tx_flags
& SKBTX_IN_PROGRESS
))
2287 skb_tstamp_tx(skb
, NULL
);
2291 * skb_tx_timestamp() - Driver hook for transmit timestamping
2293 * Ethernet MAC Drivers should call this function in their hard_xmit()
2294 * function immediately before giving the sk_buff to the MAC hardware.
2296 * @skb: A socket buffer.
2298 static inline void skb_tx_timestamp(struct sk_buff
*skb
)
2300 skb_clone_tx_timestamp(skb
);
2301 sw_tx_timestamp(skb
);
2305 * skb_complete_wifi_ack - deliver skb with wifi status
2307 * @skb: the original outgoing packet
2308 * @acked: ack status
2311 void skb_complete_wifi_ack(struct sk_buff
*skb
, bool acked
);
2313 extern __sum16
__skb_checksum_complete_head(struct sk_buff
*skb
, int len
);
2314 extern __sum16
__skb_checksum_complete(struct sk_buff
*skb
);
2316 static inline int skb_csum_unnecessary(const struct sk_buff
*skb
)
2318 return skb
->ip_summed
& CHECKSUM_UNNECESSARY
;
2322 * skb_checksum_complete - Calculate checksum of an entire packet
2323 * @skb: packet to process
2325 * This function calculates the checksum over the entire packet plus
2326 * the value of skb->csum. The latter can be used to supply the
2327 * checksum of a pseudo header as used by TCP/UDP. It returns the
2330 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
2331 * this function can be used to verify that checksum on received
2332 * packets. In that case the function should return zero if the
2333 * checksum is correct. In particular, this function will return zero
2334 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
2335 * hardware has already verified the correctness of the checksum.
2337 static inline __sum16
skb_checksum_complete(struct sk_buff
*skb
)
2339 return skb_csum_unnecessary(skb
) ?
2340 0 : __skb_checksum_complete(skb
);
2343 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2344 extern void nf_conntrack_destroy(struct nf_conntrack
*nfct
);
2345 static inline void nf_conntrack_put(struct nf_conntrack
*nfct
)
2347 if (nfct
&& atomic_dec_and_test(&nfct
->use
))
2348 nf_conntrack_destroy(nfct
);
2350 static inline void nf_conntrack_get(struct nf_conntrack
*nfct
)
2353 atomic_inc(&nfct
->use
);
2356 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2357 static inline void nf_conntrack_get_reasm(struct sk_buff
*skb
)
2360 atomic_inc(&skb
->users
);
2362 static inline void nf_conntrack_put_reasm(struct sk_buff
*skb
)
2368 #ifdef CONFIG_BRIDGE_NETFILTER
2369 static inline void nf_bridge_put(struct nf_bridge_info
*nf_bridge
)
2371 if (nf_bridge
&& atomic_dec_and_test(&nf_bridge
->use
))
2374 static inline void nf_bridge_get(struct nf_bridge_info
*nf_bridge
)
2377 atomic_inc(&nf_bridge
->use
);
2379 #endif /* CONFIG_BRIDGE_NETFILTER */
2380 static inline void nf_reset(struct sk_buff
*skb
)
2382 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2383 nf_conntrack_put(skb
->nfct
);
2386 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2387 nf_conntrack_put_reasm(skb
->nfct_reasm
);
2388 skb
->nfct_reasm
= NULL
;
2390 #ifdef CONFIG_BRIDGE_NETFILTER
2391 nf_bridge_put(skb
->nf_bridge
);
2392 skb
->nf_bridge
= NULL
;
2396 /* Note: This doesn't put any conntrack and bridge info in dst. */
2397 static inline void __nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2399 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2400 dst
->nfct
= src
->nfct
;
2401 nf_conntrack_get(src
->nfct
);
2402 dst
->nfctinfo
= src
->nfctinfo
;
2404 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2405 dst
->nfct_reasm
= src
->nfct_reasm
;
2406 nf_conntrack_get_reasm(src
->nfct_reasm
);
2408 #ifdef CONFIG_BRIDGE_NETFILTER
2409 dst
->nf_bridge
= src
->nf_bridge
;
2410 nf_bridge_get(src
->nf_bridge
);
2414 static inline void nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2416 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2417 nf_conntrack_put(dst
->nfct
);
2419 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2420 nf_conntrack_put_reasm(dst
->nfct_reasm
);
2422 #ifdef CONFIG_BRIDGE_NETFILTER
2423 nf_bridge_put(dst
->nf_bridge
);
2425 __nf_copy(dst
, src
);
2428 #ifdef CONFIG_NETWORK_SECMARK
2429 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2431 to
->secmark
= from
->secmark
;
2434 static inline void skb_init_secmark(struct sk_buff
*skb
)
2439 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2442 static inline void skb_init_secmark(struct sk_buff
*skb
)
2446 static inline void skb_set_queue_mapping(struct sk_buff
*skb
, u16 queue_mapping
)
2448 skb
->queue_mapping
= queue_mapping
;
2451 static inline u16
skb_get_queue_mapping(const struct sk_buff
*skb
)
2453 return skb
->queue_mapping
;
2456 static inline void skb_copy_queue_mapping(struct sk_buff
*to
, const struct sk_buff
*from
)
2458 to
->queue_mapping
= from
->queue_mapping
;
2461 static inline void skb_record_rx_queue(struct sk_buff
*skb
, u16 rx_queue
)
2463 skb
->queue_mapping
= rx_queue
+ 1;
2466 static inline u16
skb_get_rx_queue(const struct sk_buff
*skb
)
2468 return skb
->queue_mapping
- 1;
2471 static inline bool skb_rx_queue_recorded(const struct sk_buff
*skb
)
2473 return skb
->queue_mapping
!= 0;
2476 extern u16
__skb_tx_hash(const struct net_device
*dev
,
2477 const struct sk_buff
*skb
,
2478 unsigned int num_tx_queues
);
2481 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2486 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2492 static inline bool skb_is_gso(const struct sk_buff
*skb
)
2494 return skb_shinfo(skb
)->gso_size
;
2497 static inline bool skb_is_gso_v6(const struct sk_buff
*skb
)
2499 return skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
;
2502 extern void __skb_warn_lro_forwarding(const struct sk_buff
*skb
);
2504 static inline bool skb_warn_if_lro(const struct sk_buff
*skb
)
2506 /* LRO sets gso_size but not gso_type, whereas if GSO is really
2507 * wanted then gso_type will be set. */
2508 const struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
2510 if (skb_is_nonlinear(skb
) && shinfo
->gso_size
!= 0 &&
2511 unlikely(shinfo
->gso_type
== 0)) {
2512 __skb_warn_lro_forwarding(skb
);
2518 static inline void skb_forward_csum(struct sk_buff
*skb
)
2520 /* Unfortunately we don't support this one. Any brave souls? */
2521 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2522 skb
->ip_summed
= CHECKSUM_NONE
;
2526 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
2527 * @skb: skb to check
2529 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
2530 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
2531 * use this helper, to document places where we make this assertion.
2533 static inline void skb_checksum_none_assert(const struct sk_buff
*skb
)
2536 BUG_ON(skb
->ip_summed
!= CHECKSUM_NONE
);
2540 bool skb_partial_csum_set(struct sk_buff
*skb
, u16 start
, u16 off
);
2542 static inline bool skb_is_recycleable(const struct sk_buff
*skb
, int skb_size
)
2544 if (irqs_disabled())
2547 if (skb_shinfo(skb
)->tx_flags
& SKBTX_DEV_ZEROCOPY
)
2550 if (skb_is_nonlinear(skb
) || skb
->fclone
!= SKB_FCLONE_UNAVAILABLE
)
2553 skb_size
= SKB_DATA_ALIGN(skb_size
+ NET_SKB_PAD
);
2554 if (skb_end_pointer(skb
) - skb
->head
< skb_size
)
2557 if (skb_shared(skb
) || skb_cloned(skb
))
2562 #endif /* __KERNEL__ */
2563 #endif /* _LINUX_SKBUFF_H */