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 ctx field is used to track device context.
242 * The desc field is used to track userspace buffer index.
245 void (*callback
)(struct ubuf_info
*);
250 /* This data is invariant across clones and lives at
251 * the end of the header data, ie. at skb->end.
253 struct skb_shared_info
{
254 unsigned char nr_frags
;
256 unsigned short gso_size
;
257 /* Warning: this field is not always filled in (UFO)! */
258 unsigned short gso_segs
;
259 unsigned short gso_type
;
260 struct sk_buff
*frag_list
;
261 struct skb_shared_hwtstamps hwtstamps
;
265 * Warning : all fields before dataref are cleared in __alloc_skb()
269 /* Intermediate layers must ensure that destructor_arg
270 * remains valid until skb destructor */
271 void * destructor_arg
;
273 /* must be last field, see pskb_expand_head() */
274 skb_frag_t frags
[MAX_SKB_FRAGS
];
277 /* We divide dataref into two halves. The higher 16 bits hold references
278 * to the payload part of skb->data. The lower 16 bits hold references to
279 * the entire skb->data. A clone of a headerless skb holds the length of
280 * the header in skb->hdr_len.
282 * All users must obey the rule that the skb->data reference count must be
283 * greater than or equal to the payload reference count.
285 * Holding a reference to the payload part means that the user does not
286 * care about modifications to the header part of skb->data.
288 #define SKB_DATAREF_SHIFT 16
289 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
293 SKB_FCLONE_UNAVAILABLE
,
299 SKB_GSO_TCPV4
= 1 << 0,
300 SKB_GSO_UDP
= 1 << 1,
302 /* This indicates the skb is from an untrusted source. */
303 SKB_GSO_DODGY
= 1 << 2,
305 /* This indicates the tcp segment has CWR set. */
306 SKB_GSO_TCP_ECN
= 1 << 3,
308 SKB_GSO_TCPV6
= 1 << 4,
310 SKB_GSO_FCOE
= 1 << 5,
313 #if BITS_PER_LONG > 32
314 #define NET_SKBUFF_DATA_USES_OFFSET 1
317 #ifdef NET_SKBUFF_DATA_USES_OFFSET
318 typedef unsigned int sk_buff_data_t
;
320 typedef unsigned char *sk_buff_data_t
;
323 #if defined(CONFIG_NF_DEFRAG_IPV4) || defined(CONFIG_NF_DEFRAG_IPV4_MODULE) || \
324 defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
325 #define NET_SKBUFF_NF_DEFRAG_NEEDED 1
329 * struct sk_buff - socket buffer
330 * @next: Next buffer in list
331 * @prev: Previous buffer in list
332 * @tstamp: Time we arrived
333 * @sk: Socket we are owned by
334 * @dev: Device we arrived on/are leaving by
335 * @cb: Control buffer. Free for use by every layer. Put private vars here
336 * @_skb_refdst: destination entry (with norefcount bit)
337 * @sp: the security path, used for xfrm
338 * @len: Length of actual data
339 * @data_len: Data length
340 * @mac_len: Length of link layer header
341 * @hdr_len: writable header length of cloned skb
342 * @csum: Checksum (must include start/offset pair)
343 * @csum_start: Offset from skb->head where checksumming should start
344 * @csum_offset: Offset from csum_start where checksum should be stored
345 * @priority: Packet queueing priority
346 * @local_df: allow local fragmentation
347 * @cloned: Head may be cloned (check refcnt to be sure)
348 * @ip_summed: Driver fed us an IP checksum
349 * @nohdr: Payload reference only, must not modify header
350 * @nfctinfo: Relationship of this skb to the connection
351 * @pkt_type: Packet class
352 * @fclone: skbuff clone status
353 * @ipvs_property: skbuff is owned by ipvs
354 * @peeked: this packet has been seen already, so stats have been
355 * done for it, don't do them again
356 * @nf_trace: netfilter packet trace flag
357 * @protocol: Packet protocol from driver
358 * @destructor: Destruct function
359 * @nfct: Associated connection, if any
360 * @nfct_reasm: netfilter conntrack re-assembly pointer
361 * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
362 * @skb_iif: ifindex of device we arrived on
363 * @tc_index: Traffic control index
364 * @tc_verd: traffic control verdict
365 * @rxhash: the packet hash computed on receive
366 * @queue_mapping: Queue mapping for multiqueue devices
367 * @ndisc_nodetype: router type (from link layer)
368 * @ooo_okay: allow the mapping of a socket to a queue to be changed
369 * @l4_rxhash: indicate rxhash is a canonical 4-tuple hash over transport
371 * @wifi_acked_valid: wifi_acked was set
372 * @wifi_acked: whether frame was acked on wifi or not
373 * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS
374 * @dma_cookie: a cookie to one of several possible DMA operations
375 * done by skb DMA functions
376 * @secmark: security marking
377 * @mark: Generic packet mark
378 * @dropcount: total number of sk_receive_queue overflows
379 * @vlan_tci: vlan tag control information
380 * @transport_header: Transport layer header
381 * @network_header: Network layer header
382 * @mac_header: Link layer header
383 * @tail: Tail pointer
385 * @head: Head of buffer
386 * @data: Data head pointer
387 * @truesize: Buffer size
388 * @users: User count - see {datagram,tcp}.c
392 /* These two members must be first. */
393 struct sk_buff
*next
;
394 struct sk_buff
*prev
;
399 struct net_device
*dev
;
402 * This is the control buffer. It is free to use for every
403 * layer. Please put your private variables there. If you
404 * want to keep them across layers you have to do a skb_clone()
405 * first. This is owned by whoever has the skb queued ATM.
407 char cb
[48] __aligned(8);
409 unsigned long _skb_refdst
;
425 kmemcheck_bitfield_begin(flags1
);
436 kmemcheck_bitfield_end(flags1
);
439 void (*destructor
)(struct sk_buff
*skb
);
440 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
441 struct nf_conntrack
*nfct
;
443 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
444 struct sk_buff
*nfct_reasm
;
446 #ifdef CONFIG_BRIDGE_NETFILTER
447 struct nf_bridge_info
*nf_bridge
;
456 #ifdef CONFIG_NET_SCHED
457 __u16 tc_index
; /* traffic control index */
458 #ifdef CONFIG_NET_CLS_ACT
459 __u16 tc_verd
; /* traffic control verdict */
464 kmemcheck_bitfield_begin(flags2
);
465 #ifdef CONFIG_IPV6_NDISC_NODETYPE
466 __u8 ndisc_nodetype
:2;
470 __u8 wifi_acked_valid
:1;
473 /* 9/11 bit hole (depending on ndisc_nodetype presence) */
474 kmemcheck_bitfield_end(flags2
);
476 #ifdef CONFIG_NET_DMA
477 dma_cookie_t dma_cookie
;
479 #ifdef CONFIG_NETWORK_SECMARK
488 sk_buff_data_t transport_header
;
489 sk_buff_data_t network_header
;
490 sk_buff_data_t mac_header
;
491 /* These elements must be at the end, see alloc_skb() for details. */
496 unsigned int truesize
;
502 * Handling routines are only of interest to the kernel
504 #include <linux/slab.h>
508 * skb might have a dst pointer attached, refcounted or not.
509 * _skb_refdst low order bit is set if refcount was _not_ taken
511 #define SKB_DST_NOREF 1UL
512 #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
515 * skb_dst - returns skb dst_entry
518 * Returns skb dst_entry, regardless of reference taken or not.
520 static inline struct dst_entry
*skb_dst(const struct sk_buff
*skb
)
522 /* If refdst was not refcounted, check we still are in a
523 * rcu_read_lock section
525 WARN_ON((skb
->_skb_refdst
& SKB_DST_NOREF
) &&
526 !rcu_read_lock_held() &&
527 !rcu_read_lock_bh_held());
528 return (struct dst_entry
*)(skb
->_skb_refdst
& SKB_DST_PTRMASK
);
532 * skb_dst_set - sets skb dst
536 * Sets skb dst, assuming a reference was taken on dst and should
537 * be released by skb_dst_drop()
539 static inline void skb_dst_set(struct sk_buff
*skb
, struct dst_entry
*dst
)
541 skb
->_skb_refdst
= (unsigned long)dst
;
544 extern void skb_dst_set_noref(struct sk_buff
*skb
, struct dst_entry
*dst
);
547 * skb_dst_is_noref - Test if skb dst isn't refcounted
550 static inline bool skb_dst_is_noref(const struct sk_buff
*skb
)
552 return (skb
->_skb_refdst
& SKB_DST_NOREF
) && skb_dst(skb
);
555 static inline struct rtable
*skb_rtable(const struct sk_buff
*skb
)
557 return (struct rtable
*)skb_dst(skb
);
560 extern void kfree_skb(struct sk_buff
*skb
);
561 extern void consume_skb(struct sk_buff
*skb
);
562 extern void __kfree_skb(struct sk_buff
*skb
);
563 extern struct sk_buff
*__alloc_skb(unsigned int size
,
564 gfp_t priority
, int fclone
, int node
);
565 extern struct sk_buff
*build_skb(void *data
);
566 static inline struct sk_buff
*alloc_skb(unsigned int size
,
569 return __alloc_skb(size
, priority
, 0, NUMA_NO_NODE
);
572 static inline struct sk_buff
*alloc_skb_fclone(unsigned int size
,
575 return __alloc_skb(size
, priority
, 1, NUMA_NO_NODE
);
578 extern void skb_recycle(struct sk_buff
*skb
);
579 extern bool skb_recycle_check(struct sk_buff
*skb
, int skb_size
);
581 extern struct sk_buff
*skb_morph(struct sk_buff
*dst
, struct sk_buff
*src
);
582 extern int skb_copy_ubufs(struct sk_buff
*skb
, gfp_t gfp_mask
);
583 extern struct sk_buff
*skb_clone(struct sk_buff
*skb
,
585 extern struct sk_buff
*skb_copy(const struct sk_buff
*skb
,
587 extern struct sk_buff
*__pskb_copy(struct sk_buff
*skb
,
588 int headroom
, gfp_t gfp_mask
);
590 extern int pskb_expand_head(struct sk_buff
*skb
,
591 int nhead
, int ntail
,
593 extern struct sk_buff
*skb_realloc_headroom(struct sk_buff
*skb
,
594 unsigned int headroom
);
595 extern struct sk_buff
*skb_copy_expand(const struct sk_buff
*skb
,
596 int newheadroom
, int newtailroom
,
598 extern int skb_to_sgvec(struct sk_buff
*skb
,
599 struct scatterlist
*sg
, int offset
,
601 extern int skb_cow_data(struct sk_buff
*skb
, int tailbits
,
602 struct sk_buff
**trailer
);
603 extern int skb_pad(struct sk_buff
*skb
, int pad
);
604 #define dev_kfree_skb(a) consume_skb(a)
606 extern int skb_append_datato_frags(struct sock
*sk
, struct sk_buff
*skb
,
607 int getfrag(void *from
, char *to
, int offset
,
608 int len
,int odd
, struct sk_buff
*skb
),
609 void *from
, int length
);
611 struct skb_seq_state
{
615 __u32 stepped_offset
;
616 struct sk_buff
*root_skb
;
617 struct sk_buff
*cur_skb
;
621 extern void skb_prepare_seq_read(struct sk_buff
*skb
,
622 unsigned int from
, unsigned int to
,
623 struct skb_seq_state
*st
);
624 extern unsigned int skb_seq_read(unsigned int consumed
, const u8
**data
,
625 struct skb_seq_state
*st
);
626 extern void skb_abort_seq_read(struct skb_seq_state
*st
);
628 extern unsigned int skb_find_text(struct sk_buff
*skb
, unsigned int from
,
629 unsigned int to
, struct ts_config
*config
,
630 struct ts_state
*state
);
632 extern void __skb_get_rxhash(struct sk_buff
*skb
);
633 static inline __u32
skb_get_rxhash(struct sk_buff
*skb
)
636 __skb_get_rxhash(skb
);
641 #ifdef NET_SKBUFF_DATA_USES_OFFSET
642 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
644 return skb
->head
+ skb
->end
;
647 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
654 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
656 static inline struct skb_shared_hwtstamps
*skb_hwtstamps(struct sk_buff
*skb
)
658 return &skb_shinfo(skb
)->hwtstamps
;
662 * skb_queue_empty - check if a queue is empty
665 * Returns true if the queue is empty, false otherwise.
667 static inline int skb_queue_empty(const struct sk_buff_head
*list
)
669 return list
->next
== (struct sk_buff
*)list
;
673 * skb_queue_is_last - check if skb is the last entry in the queue
677 * Returns true if @skb is the last buffer on the list.
679 static inline bool skb_queue_is_last(const struct sk_buff_head
*list
,
680 const struct sk_buff
*skb
)
682 return skb
->next
== (struct sk_buff
*)list
;
686 * skb_queue_is_first - check if skb is the first entry in the queue
690 * Returns true if @skb is the first buffer on the list.
692 static inline bool skb_queue_is_first(const struct sk_buff_head
*list
,
693 const struct sk_buff
*skb
)
695 return skb
->prev
== (struct sk_buff
*)list
;
699 * skb_queue_next - return the next packet in the queue
701 * @skb: current buffer
703 * Return the next packet in @list after @skb. It is only valid to
704 * call this if skb_queue_is_last() evaluates to false.
706 static inline struct sk_buff
*skb_queue_next(const struct sk_buff_head
*list
,
707 const struct sk_buff
*skb
)
709 /* This BUG_ON may seem severe, but if we just return then we
710 * are going to dereference garbage.
712 BUG_ON(skb_queue_is_last(list
, skb
));
717 * skb_queue_prev - return the prev packet in the queue
719 * @skb: current buffer
721 * Return the prev packet in @list before @skb. It is only valid to
722 * call this if skb_queue_is_first() evaluates to false.
724 static inline struct sk_buff
*skb_queue_prev(const struct sk_buff_head
*list
,
725 const struct sk_buff
*skb
)
727 /* This BUG_ON may seem severe, but if we just return then we
728 * are going to dereference garbage.
730 BUG_ON(skb_queue_is_first(list
, skb
));
735 * skb_get - reference buffer
736 * @skb: buffer to reference
738 * Makes another reference to a socket buffer and returns a pointer
741 static inline struct sk_buff
*skb_get(struct sk_buff
*skb
)
743 atomic_inc(&skb
->users
);
748 * If users == 1, we are the only owner and are can avoid redundant
753 * skb_cloned - is the buffer a clone
754 * @skb: buffer to check
756 * Returns true if the buffer was generated with skb_clone() and is
757 * one of multiple shared copies of the buffer. Cloned buffers are
758 * shared data so must not be written to under normal circumstances.
760 static inline int skb_cloned(const struct sk_buff
*skb
)
762 return skb
->cloned
&&
763 (atomic_read(&skb_shinfo(skb
)->dataref
) & SKB_DATAREF_MASK
) != 1;
767 * skb_header_cloned - is the header a clone
768 * @skb: buffer to check
770 * Returns true if modifying the header part of the buffer requires
771 * the data to be copied.
773 static inline int skb_header_cloned(const struct sk_buff
*skb
)
780 dataref
= atomic_read(&skb_shinfo(skb
)->dataref
);
781 dataref
= (dataref
& SKB_DATAREF_MASK
) - (dataref
>> SKB_DATAREF_SHIFT
);
786 * skb_header_release - release reference to header
787 * @skb: buffer to operate on
789 * Drop a reference to the header part of the buffer. This is done
790 * by acquiring a payload reference. You must not read from the header
791 * part of skb->data after this.
793 static inline void skb_header_release(struct sk_buff
*skb
)
797 atomic_add(1 << SKB_DATAREF_SHIFT
, &skb_shinfo(skb
)->dataref
);
801 * skb_shared - is the buffer shared
802 * @skb: buffer to check
804 * Returns true if more than one person has a reference to this
807 static inline int skb_shared(const struct sk_buff
*skb
)
809 return atomic_read(&skb
->users
) != 1;
813 * skb_share_check - check if buffer is shared and if so clone it
814 * @skb: buffer to check
815 * @pri: priority for memory allocation
817 * If the buffer is shared the buffer is cloned and the old copy
818 * drops a reference. A new clone with a single reference is returned.
819 * If the buffer is not shared the original buffer is returned. When
820 * being called from interrupt status or with spinlocks held pri must
823 * NULL is returned on a memory allocation failure.
825 static inline struct sk_buff
*skb_share_check(struct sk_buff
*skb
,
828 might_sleep_if(pri
& __GFP_WAIT
);
829 if (skb_shared(skb
)) {
830 struct sk_buff
*nskb
= skb_clone(skb
, pri
);
838 * Copy shared buffers into a new sk_buff. We effectively do COW on
839 * packets to handle cases where we have a local reader and forward
840 * and a couple of other messy ones. The normal one is tcpdumping
841 * a packet thats being forwarded.
845 * skb_unshare - make a copy of a shared buffer
846 * @skb: buffer to check
847 * @pri: priority for memory allocation
849 * If the socket buffer is a clone then this function creates a new
850 * copy of the data, drops a reference count on the old copy and returns
851 * the new copy with the reference count at 1. If the buffer is not a clone
852 * the original buffer is returned. When called with a spinlock held or
853 * from interrupt state @pri must be %GFP_ATOMIC
855 * %NULL is returned on a memory allocation failure.
857 static inline struct sk_buff
*skb_unshare(struct sk_buff
*skb
,
860 might_sleep_if(pri
& __GFP_WAIT
);
861 if (skb_cloned(skb
)) {
862 struct sk_buff
*nskb
= skb_copy(skb
, pri
);
863 kfree_skb(skb
); /* Free our shared copy */
870 * skb_peek - peek at the head of an &sk_buff_head
871 * @list_: list to peek at
873 * Peek an &sk_buff. Unlike most other operations you _MUST_
874 * be careful with this one. A peek leaves the buffer on the
875 * list and someone else may run off with it. You must hold
876 * the appropriate locks or have a private queue to do this.
878 * Returns %NULL for an empty list or a pointer to the head element.
879 * The reference count is not incremented and the reference is therefore
880 * volatile. Use with caution.
882 static inline struct sk_buff
*skb_peek(const struct sk_buff_head
*list_
)
884 struct sk_buff
*list
= ((const struct sk_buff
*)list_
)->next
;
885 if (list
== (struct sk_buff
*)list_
)
891 * skb_peek_next - peek skb following the given one from a queue
892 * @skb: skb to start from
893 * @list_: list to peek at
895 * Returns %NULL when the end of the list is met or a pointer to the
896 * next element. The reference count is not incremented and the
897 * reference is therefore volatile. Use with caution.
899 static inline struct sk_buff
*skb_peek_next(struct sk_buff
*skb
,
900 const struct sk_buff_head
*list_
)
902 struct sk_buff
*next
= skb
->next
;
903 if (next
== (struct sk_buff
*)list_
)
909 * skb_peek_tail - peek at the tail of an &sk_buff_head
910 * @list_: list to peek at
912 * Peek an &sk_buff. Unlike most other operations you _MUST_
913 * be careful with this one. A peek leaves the buffer on the
914 * list and someone else may run off with it. You must hold
915 * the appropriate locks or have a private queue to do this.
917 * Returns %NULL for an empty list or a pointer to the tail element.
918 * The reference count is not incremented and the reference is therefore
919 * volatile. Use with caution.
921 static inline struct sk_buff
*skb_peek_tail(const struct sk_buff_head
*list_
)
923 struct sk_buff
*list
= ((const struct sk_buff
*)list_
)->prev
;
924 if (list
== (struct sk_buff
*)list_
)
930 * skb_queue_len - get queue length
931 * @list_: list to measure
933 * Return the length of an &sk_buff queue.
935 static inline __u32
skb_queue_len(const struct sk_buff_head
*list_
)
941 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
942 * @list: queue to initialize
944 * This initializes only the list and queue length aspects of
945 * an sk_buff_head object. This allows to initialize the list
946 * aspects of an sk_buff_head without reinitializing things like
947 * the spinlock. It can also be used for on-stack sk_buff_head
948 * objects where the spinlock is known to not be used.
950 static inline void __skb_queue_head_init(struct sk_buff_head
*list
)
952 list
->prev
= list
->next
= (struct sk_buff
*)list
;
957 * This function creates a split out lock class for each invocation;
958 * this is needed for now since a whole lot of users of the skb-queue
959 * infrastructure in drivers have different locking usage (in hardirq)
960 * than the networking core (in softirq only). In the long run either the
961 * network layer or drivers should need annotation to consolidate the
962 * main types of usage into 3 classes.
964 static inline void skb_queue_head_init(struct sk_buff_head
*list
)
966 spin_lock_init(&list
->lock
);
967 __skb_queue_head_init(list
);
970 static inline void skb_queue_head_init_class(struct sk_buff_head
*list
,
971 struct lock_class_key
*class)
973 skb_queue_head_init(list
);
974 lockdep_set_class(&list
->lock
, class);
978 * Insert an sk_buff on a list.
980 * The "__skb_xxxx()" functions are the non-atomic ones that
981 * can only be called with interrupts disabled.
983 extern void skb_insert(struct sk_buff
*old
, struct sk_buff
*newsk
, struct sk_buff_head
*list
);
984 static inline void __skb_insert(struct sk_buff
*newsk
,
985 struct sk_buff
*prev
, struct sk_buff
*next
,
986 struct sk_buff_head
*list
)
990 next
->prev
= prev
->next
= newsk
;
994 static inline void __skb_queue_splice(const struct sk_buff_head
*list
,
995 struct sk_buff
*prev
,
996 struct sk_buff
*next
)
998 struct sk_buff
*first
= list
->next
;
999 struct sk_buff
*last
= list
->prev
;
1009 * skb_queue_splice - join two skb lists, this is designed for stacks
1010 * @list: the new list to add
1011 * @head: the place to add it in the first list
1013 static inline void skb_queue_splice(const struct sk_buff_head
*list
,
1014 struct sk_buff_head
*head
)
1016 if (!skb_queue_empty(list
)) {
1017 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1018 head
->qlen
+= list
->qlen
;
1023 * skb_queue_splice_init - join two skb lists and reinitialise the emptied list
1024 * @list: the new list to add
1025 * @head: the place to add it in the first list
1027 * The list at @list is reinitialised
1029 static inline void skb_queue_splice_init(struct sk_buff_head
*list
,
1030 struct sk_buff_head
*head
)
1032 if (!skb_queue_empty(list
)) {
1033 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1034 head
->qlen
+= list
->qlen
;
1035 __skb_queue_head_init(list
);
1040 * skb_queue_splice_tail - join two skb lists, each list being a queue
1041 * @list: the new list to add
1042 * @head: the place to add it in the first list
1044 static inline void skb_queue_splice_tail(const struct sk_buff_head
*list
,
1045 struct sk_buff_head
*head
)
1047 if (!skb_queue_empty(list
)) {
1048 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1049 head
->qlen
+= list
->qlen
;
1054 * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list
1055 * @list: the new list to add
1056 * @head: the place to add it in the first list
1058 * Each of the lists is a queue.
1059 * The list at @list is reinitialised
1061 static inline void skb_queue_splice_tail_init(struct sk_buff_head
*list
,
1062 struct sk_buff_head
*head
)
1064 if (!skb_queue_empty(list
)) {
1065 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1066 head
->qlen
+= list
->qlen
;
1067 __skb_queue_head_init(list
);
1072 * __skb_queue_after - queue a buffer at the list head
1073 * @list: list to use
1074 * @prev: place after this buffer
1075 * @newsk: buffer to queue
1077 * Queue a buffer int the middle of a list. This function takes no locks
1078 * and you must therefore hold required locks before calling it.
1080 * A buffer cannot be placed on two lists at the same time.
1082 static inline void __skb_queue_after(struct sk_buff_head
*list
,
1083 struct sk_buff
*prev
,
1084 struct sk_buff
*newsk
)
1086 __skb_insert(newsk
, prev
, prev
->next
, list
);
1089 extern void skb_append(struct sk_buff
*old
, struct sk_buff
*newsk
,
1090 struct sk_buff_head
*list
);
1092 static inline void __skb_queue_before(struct sk_buff_head
*list
,
1093 struct sk_buff
*next
,
1094 struct sk_buff
*newsk
)
1096 __skb_insert(newsk
, next
->prev
, next
, list
);
1100 * __skb_queue_head - queue a buffer at the list head
1101 * @list: list to use
1102 * @newsk: buffer to queue
1104 * Queue a buffer at the start of a list. This function takes no locks
1105 * and you must therefore hold required locks before calling it.
1107 * A buffer cannot be placed on two lists at the same time.
1109 extern void skb_queue_head(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1110 static inline void __skb_queue_head(struct sk_buff_head
*list
,
1111 struct sk_buff
*newsk
)
1113 __skb_queue_after(list
, (struct sk_buff
*)list
, newsk
);
1117 * __skb_queue_tail - queue a buffer at the list tail
1118 * @list: list to use
1119 * @newsk: buffer to queue
1121 * Queue a buffer at the end of a list. This function takes no locks
1122 * and you must therefore hold required locks before calling it.
1124 * A buffer cannot be placed on two lists at the same time.
1126 extern void skb_queue_tail(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1127 static inline void __skb_queue_tail(struct sk_buff_head
*list
,
1128 struct sk_buff
*newsk
)
1130 __skb_queue_before(list
, (struct sk_buff
*)list
, newsk
);
1134 * remove sk_buff from list. _Must_ be called atomically, and with
1137 extern void skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
);
1138 static inline void __skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
)
1140 struct sk_buff
*next
, *prev
;
1145 skb
->next
= skb
->prev
= NULL
;
1151 * __skb_dequeue - remove from the head of the queue
1152 * @list: list to dequeue from
1154 * Remove the head of the list. This function does not take any locks
1155 * so must be used with appropriate locks held only. The head item is
1156 * returned or %NULL if the list is empty.
1158 extern struct sk_buff
*skb_dequeue(struct sk_buff_head
*list
);
1159 static inline struct sk_buff
*__skb_dequeue(struct sk_buff_head
*list
)
1161 struct sk_buff
*skb
= skb_peek(list
);
1163 __skb_unlink(skb
, list
);
1168 * __skb_dequeue_tail - remove from the tail of the queue
1169 * @list: list to dequeue from
1171 * Remove the tail of the list. This function does not take any locks
1172 * so must be used with appropriate locks held only. The tail item is
1173 * returned or %NULL if the list is empty.
1175 extern struct sk_buff
*skb_dequeue_tail(struct sk_buff_head
*list
);
1176 static inline struct sk_buff
*__skb_dequeue_tail(struct sk_buff_head
*list
)
1178 struct sk_buff
*skb
= skb_peek_tail(list
);
1180 __skb_unlink(skb
, list
);
1185 static inline bool skb_is_nonlinear(const struct sk_buff
*skb
)
1187 return skb
->data_len
;
1190 static inline unsigned int skb_headlen(const struct sk_buff
*skb
)
1192 return skb
->len
- skb
->data_len
;
1195 static inline int skb_pagelen(const struct sk_buff
*skb
)
1199 for (i
= (int)skb_shinfo(skb
)->nr_frags
- 1; i
>= 0; i
--)
1200 len
+= skb_frag_size(&skb_shinfo(skb
)->frags
[i
]);
1201 return len
+ skb_headlen(skb
);
1205 * __skb_fill_page_desc - initialise a paged fragment in an skb
1206 * @skb: buffer containing fragment to be initialised
1207 * @i: paged fragment index to initialise
1208 * @page: the page to use for this fragment
1209 * @off: the offset to the data with @page
1210 * @size: the length of the data
1212 * Initialises the @i'th fragment of @skb to point to &size bytes at
1213 * offset @off within @page.
1215 * Does not take any additional reference on the fragment.
1217 static inline void __skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1218 struct page
*page
, int off
, int size
)
1220 skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
];
1222 frag
->page
.p
= page
;
1223 frag
->page_offset
= off
;
1224 skb_frag_size_set(frag
, size
);
1228 * skb_fill_page_desc - initialise a paged fragment in an skb
1229 * @skb: buffer containing fragment to be initialised
1230 * @i: paged fragment index to initialise
1231 * @page: the page to use for this fragment
1232 * @off: the offset to the data with @page
1233 * @size: the length of the data
1235 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
1236 * @skb to point to &size bytes at offset @off within @page. In
1237 * addition updates @skb such that @i is the last fragment.
1239 * Does not take any additional reference on the fragment.
1241 static inline void skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1242 struct page
*page
, int off
, int size
)
1244 __skb_fill_page_desc(skb
, i
, page
, off
, size
);
1245 skb_shinfo(skb
)->nr_frags
= i
+ 1;
1248 extern void skb_add_rx_frag(struct sk_buff
*skb
, int i
, struct page
*page
,
1249 int off
, int size
, unsigned int truesize
);
1251 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
1252 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb))
1253 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
1255 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1256 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1258 return skb
->head
+ skb
->tail
;
1261 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1263 skb
->tail
= skb
->data
- skb
->head
;
1266 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1268 skb_reset_tail_pointer(skb
);
1269 skb
->tail
+= offset
;
1271 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1272 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1277 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1279 skb
->tail
= skb
->data
;
1282 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1284 skb
->tail
= skb
->data
+ offset
;
1287 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1290 * Add data to an sk_buff
1292 extern unsigned char *skb_put(struct sk_buff
*skb
, unsigned int len
);
1293 static inline unsigned char *__skb_put(struct sk_buff
*skb
, unsigned int len
)
1295 unsigned char *tmp
= skb_tail_pointer(skb
);
1296 SKB_LINEAR_ASSERT(skb
);
1302 extern unsigned char *skb_push(struct sk_buff
*skb
, unsigned int len
);
1303 static inline unsigned char *__skb_push(struct sk_buff
*skb
, unsigned int len
)
1310 extern unsigned char *skb_pull(struct sk_buff
*skb
, unsigned int len
);
1311 static inline unsigned char *__skb_pull(struct sk_buff
*skb
, unsigned int len
)
1314 BUG_ON(skb
->len
< skb
->data_len
);
1315 return skb
->data
+= len
;
1318 static inline unsigned char *skb_pull_inline(struct sk_buff
*skb
, unsigned int len
)
1320 return unlikely(len
> skb
->len
) ? NULL
: __skb_pull(skb
, len
);
1323 extern unsigned char *__pskb_pull_tail(struct sk_buff
*skb
, int delta
);
1325 static inline unsigned char *__pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1327 if (len
> skb_headlen(skb
) &&
1328 !__pskb_pull_tail(skb
, len
- skb_headlen(skb
)))
1331 return skb
->data
+= len
;
1334 static inline unsigned char *pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1336 return unlikely(len
> skb
->len
) ? NULL
: __pskb_pull(skb
, len
);
1339 static inline int pskb_may_pull(struct sk_buff
*skb
, unsigned int len
)
1341 if (likely(len
<= skb_headlen(skb
)))
1343 if (unlikely(len
> skb
->len
))
1345 return __pskb_pull_tail(skb
, len
- skb_headlen(skb
)) != NULL
;
1349 * skb_headroom - bytes at buffer head
1350 * @skb: buffer to check
1352 * Return the number of bytes of free space at the head of an &sk_buff.
1354 static inline unsigned int skb_headroom(const struct sk_buff
*skb
)
1356 return skb
->data
- skb
->head
;
1360 * skb_tailroom - bytes at buffer end
1361 * @skb: buffer to check
1363 * Return the number of bytes of free space at the tail of an sk_buff
1365 static inline int skb_tailroom(const struct sk_buff
*skb
)
1367 return skb_is_nonlinear(skb
) ? 0 : skb
->end
- skb
->tail
;
1371 * skb_availroom - bytes at buffer end
1372 * @skb: buffer to check
1374 * Return the number of bytes of free space at the tail of an sk_buff
1375 * allocated by sk_stream_alloc()
1377 static inline int skb_availroom(const struct sk_buff
*skb
)
1379 return skb_is_nonlinear(skb
) ? 0 : skb
->avail_size
- skb
->len
;
1383 * skb_reserve - adjust headroom
1384 * @skb: buffer to alter
1385 * @len: bytes to move
1387 * Increase the headroom of an empty &sk_buff by reducing the tail
1388 * room. This is only allowed for an empty buffer.
1390 static inline void skb_reserve(struct sk_buff
*skb
, int len
)
1396 static inline void skb_reset_mac_len(struct sk_buff
*skb
)
1398 skb
->mac_len
= skb
->network_header
- skb
->mac_header
;
1401 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1402 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1404 return skb
->head
+ skb
->transport_header
;
1407 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1409 skb
->transport_header
= skb
->data
- skb
->head
;
1412 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1415 skb_reset_transport_header(skb
);
1416 skb
->transport_header
+= offset
;
1419 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1421 return skb
->head
+ skb
->network_header
;
1424 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1426 skb
->network_header
= skb
->data
- skb
->head
;
1429 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1431 skb_reset_network_header(skb
);
1432 skb
->network_header
+= offset
;
1435 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1437 return skb
->head
+ skb
->mac_header
;
1440 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1442 return skb
->mac_header
!= ~0U;
1445 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1447 skb
->mac_header
= skb
->data
- skb
->head
;
1450 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1452 skb_reset_mac_header(skb
);
1453 skb
->mac_header
+= offset
;
1456 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1458 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1460 return skb
->transport_header
;
1463 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1465 skb
->transport_header
= skb
->data
;
1468 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1471 skb
->transport_header
= skb
->data
+ offset
;
1474 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1476 return skb
->network_header
;
1479 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1481 skb
->network_header
= skb
->data
;
1484 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1486 skb
->network_header
= skb
->data
+ offset
;
1489 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1491 return skb
->mac_header
;
1494 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1496 return skb
->mac_header
!= NULL
;
1499 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1501 skb
->mac_header
= skb
->data
;
1504 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1506 skb
->mac_header
= skb
->data
+ offset
;
1508 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1510 static inline void skb_mac_header_rebuild(struct sk_buff
*skb
)
1512 if (skb_mac_header_was_set(skb
)) {
1513 const unsigned char *old_mac
= skb_mac_header(skb
);
1515 skb_set_mac_header(skb
, -skb
->mac_len
);
1516 memmove(skb_mac_header(skb
), old_mac
, skb
->mac_len
);
1520 static inline int skb_checksum_start_offset(const struct sk_buff
*skb
)
1522 return skb
->csum_start
- skb_headroom(skb
);
1525 static inline int skb_transport_offset(const struct sk_buff
*skb
)
1527 return skb_transport_header(skb
) - skb
->data
;
1530 static inline u32
skb_network_header_len(const struct sk_buff
*skb
)
1532 return skb
->transport_header
- skb
->network_header
;
1535 static inline int skb_network_offset(const struct sk_buff
*skb
)
1537 return skb_network_header(skb
) - skb
->data
;
1540 static inline int pskb_network_may_pull(struct sk_buff
*skb
, unsigned int len
)
1542 return pskb_may_pull(skb
, skb_network_offset(skb
) + len
);
1546 * CPUs often take a performance hit when accessing unaligned memory
1547 * locations. The actual performance hit varies, it can be small if the
1548 * hardware handles it or large if we have to take an exception and fix it
1551 * Since an ethernet header is 14 bytes network drivers often end up with
1552 * the IP header at an unaligned offset. The IP header can be aligned by
1553 * shifting the start of the packet by 2 bytes. Drivers should do this
1556 * skb_reserve(skb, NET_IP_ALIGN);
1558 * The downside to this alignment of the IP header is that the DMA is now
1559 * unaligned. On some architectures the cost of an unaligned DMA is high
1560 * and this cost outweighs the gains made by aligning the IP header.
1562 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1565 #ifndef NET_IP_ALIGN
1566 #define NET_IP_ALIGN 2
1570 * The networking layer reserves some headroom in skb data (via
1571 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1572 * the header has to grow. In the default case, if the header has to grow
1573 * 32 bytes or less we avoid the reallocation.
1575 * Unfortunately this headroom changes the DMA alignment of the resulting
1576 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1577 * on some architectures. An architecture can override this value,
1578 * perhaps setting it to a cacheline in size (since that will maintain
1579 * cacheline alignment of the DMA). It must be a power of 2.
1581 * Various parts of the networking layer expect at least 32 bytes of
1582 * headroom, you should not reduce this.
1584 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
1585 * to reduce average number of cache lines per packet.
1586 * get_rps_cpus() for example only access one 64 bytes aligned block :
1587 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
1590 #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
1593 extern int ___pskb_trim(struct sk_buff
*skb
, unsigned int len
);
1595 static inline void __skb_trim(struct sk_buff
*skb
, unsigned int len
)
1597 if (unlikely(skb_is_nonlinear(skb
))) {
1602 skb_set_tail_pointer(skb
, len
);
1605 extern void skb_trim(struct sk_buff
*skb
, unsigned int len
);
1607 static inline int __pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1610 return ___pskb_trim(skb
, len
);
1611 __skb_trim(skb
, len
);
1615 static inline int pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1617 return (len
< skb
->len
) ? __pskb_trim(skb
, len
) : 0;
1621 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1622 * @skb: buffer to alter
1625 * This is identical to pskb_trim except that the caller knows that
1626 * the skb is not cloned so we should never get an error due to out-
1629 static inline void pskb_trim_unique(struct sk_buff
*skb
, unsigned int len
)
1631 int err
= pskb_trim(skb
, len
);
1636 * skb_orphan - orphan a buffer
1637 * @skb: buffer to orphan
1639 * If a buffer currently has an owner then we call the owner's
1640 * destructor function and make the @skb unowned. The buffer continues
1641 * to exist but is no longer charged to its former owner.
1643 static inline void skb_orphan(struct sk_buff
*skb
)
1645 if (skb
->destructor
)
1646 skb
->destructor(skb
);
1647 skb
->destructor
= NULL
;
1652 * __skb_queue_purge - empty a list
1653 * @list: list to empty
1655 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1656 * the list and one reference dropped. This function does not take the
1657 * list lock and the caller must hold the relevant locks to use it.
1659 extern void skb_queue_purge(struct sk_buff_head
*list
);
1660 static inline void __skb_queue_purge(struct sk_buff_head
*list
)
1662 struct sk_buff
*skb
;
1663 while ((skb
= __skb_dequeue(list
)) != NULL
)
1668 * __dev_alloc_skb - allocate an skbuff for receiving
1669 * @length: length to allocate
1670 * @gfp_mask: get_free_pages mask, passed to alloc_skb
1672 * Allocate a new &sk_buff and assign it a usage count of one. The
1673 * buffer has unspecified headroom built in. Users should allocate
1674 * the headroom they think they need without accounting for the
1675 * built in space. The built in space is used for optimisations.
1677 * %NULL is returned if there is no free memory.
1679 static inline struct sk_buff
*__dev_alloc_skb(unsigned int length
,
1682 struct sk_buff
*skb
= alloc_skb(length
+ NET_SKB_PAD
, gfp_mask
);
1684 skb_reserve(skb
, NET_SKB_PAD
);
1688 extern struct sk_buff
*dev_alloc_skb(unsigned int length
);
1690 extern struct sk_buff
*__netdev_alloc_skb(struct net_device
*dev
,
1691 unsigned int length
, gfp_t gfp_mask
);
1694 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1695 * @dev: network device to receive on
1696 * @length: length to allocate
1698 * Allocate a new &sk_buff and assign it a usage count of one. The
1699 * buffer has unspecified headroom built in. Users should allocate
1700 * the headroom they think they need without accounting for the
1701 * built in space. The built in space is used for optimisations.
1703 * %NULL is returned if there is no free memory. Although this function
1704 * allocates memory it can be called from an interrupt.
1706 static inline struct sk_buff
*netdev_alloc_skb(struct net_device
*dev
,
1707 unsigned int length
)
1709 return __netdev_alloc_skb(dev
, length
, GFP_ATOMIC
);
1712 static inline struct sk_buff
*__netdev_alloc_skb_ip_align(struct net_device
*dev
,
1713 unsigned int length
, gfp_t gfp
)
1715 struct sk_buff
*skb
= __netdev_alloc_skb(dev
, length
+ NET_IP_ALIGN
, gfp
);
1717 if (NET_IP_ALIGN
&& skb
)
1718 skb_reserve(skb
, NET_IP_ALIGN
);
1722 static inline struct sk_buff
*netdev_alloc_skb_ip_align(struct net_device
*dev
,
1723 unsigned int length
)
1725 return __netdev_alloc_skb_ip_align(dev
, length
, GFP_ATOMIC
);
1729 * skb_frag_page - retrieve the page refered to by a paged fragment
1730 * @frag: the paged fragment
1732 * Returns the &struct page associated with @frag.
1734 static inline struct page
*skb_frag_page(const skb_frag_t
*frag
)
1736 return frag
->page
.p
;
1740 * __skb_frag_ref - take an addition reference on a paged fragment.
1741 * @frag: the paged fragment
1743 * Takes an additional reference on the paged fragment @frag.
1745 static inline void __skb_frag_ref(skb_frag_t
*frag
)
1747 get_page(skb_frag_page(frag
));
1751 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
1753 * @f: the fragment offset.
1755 * Takes an additional reference on the @f'th paged fragment of @skb.
1757 static inline void skb_frag_ref(struct sk_buff
*skb
, int f
)
1759 __skb_frag_ref(&skb_shinfo(skb
)->frags
[f
]);
1763 * __skb_frag_unref - release a reference on a paged fragment.
1764 * @frag: the paged fragment
1766 * Releases a reference on the paged fragment @frag.
1768 static inline void __skb_frag_unref(skb_frag_t
*frag
)
1770 put_page(skb_frag_page(frag
));
1774 * skb_frag_unref - release a reference on a paged fragment of an skb.
1776 * @f: the fragment offset
1778 * Releases a reference on the @f'th paged fragment of @skb.
1780 static inline void skb_frag_unref(struct sk_buff
*skb
, int f
)
1782 __skb_frag_unref(&skb_shinfo(skb
)->frags
[f
]);
1786 * skb_frag_address - gets the address of the data contained in a paged fragment
1787 * @frag: the paged fragment buffer
1789 * Returns the address of the data within @frag. The page must already
1792 static inline void *skb_frag_address(const skb_frag_t
*frag
)
1794 return page_address(skb_frag_page(frag
)) + frag
->page_offset
;
1798 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
1799 * @frag: the paged fragment buffer
1801 * Returns the address of the data within @frag. Checks that the page
1802 * is mapped and returns %NULL otherwise.
1804 static inline void *skb_frag_address_safe(const skb_frag_t
*frag
)
1806 void *ptr
= page_address(skb_frag_page(frag
));
1810 return ptr
+ frag
->page_offset
;
1814 * __skb_frag_set_page - sets the page contained in a paged fragment
1815 * @frag: the paged fragment
1816 * @page: the page to set
1818 * Sets the fragment @frag to contain @page.
1820 static inline void __skb_frag_set_page(skb_frag_t
*frag
, struct page
*page
)
1822 frag
->page
.p
= page
;
1826 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
1828 * @f: the fragment offset
1829 * @page: the page to set
1831 * Sets the @f'th fragment of @skb to contain @page.
1833 static inline void skb_frag_set_page(struct sk_buff
*skb
, int f
,
1836 __skb_frag_set_page(&skb_shinfo(skb
)->frags
[f
], page
);
1840 * skb_frag_dma_map - maps a paged fragment via the DMA API
1841 * @dev: the device to map the fragment to
1842 * @frag: the paged fragment to map
1843 * @offset: the offset within the fragment (starting at the
1844 * fragment's own offset)
1845 * @size: the number of bytes to map
1846 * @dir: the direction of the mapping (%PCI_DMA_*)
1848 * Maps the page associated with @frag to @device.
1850 static inline dma_addr_t
skb_frag_dma_map(struct device
*dev
,
1851 const skb_frag_t
*frag
,
1852 size_t offset
, size_t size
,
1853 enum dma_data_direction dir
)
1855 return dma_map_page(dev
, skb_frag_page(frag
),
1856 frag
->page_offset
+ offset
, size
, dir
);
1859 static inline struct sk_buff
*pskb_copy(struct sk_buff
*skb
,
1862 return __pskb_copy(skb
, skb_headroom(skb
), gfp_mask
);
1866 * skb_clone_writable - is the header of a clone writable
1867 * @skb: buffer to check
1868 * @len: length up to which to write
1870 * Returns true if modifying the header part of the cloned buffer
1871 * does not requires the data to be copied.
1873 static inline int skb_clone_writable(const struct sk_buff
*skb
, unsigned int len
)
1875 return !skb_header_cloned(skb
) &&
1876 skb_headroom(skb
) + len
<= skb
->hdr_len
;
1879 static inline int __skb_cow(struct sk_buff
*skb
, unsigned int headroom
,
1884 if (headroom
< NET_SKB_PAD
)
1885 headroom
= NET_SKB_PAD
;
1886 if (headroom
> skb_headroom(skb
))
1887 delta
= headroom
- skb_headroom(skb
);
1889 if (delta
|| cloned
)
1890 return pskb_expand_head(skb
, ALIGN(delta
, NET_SKB_PAD
), 0,
1896 * skb_cow - copy header of skb when it is required
1897 * @skb: buffer to cow
1898 * @headroom: needed headroom
1900 * If the skb passed lacks sufficient headroom or its data part
1901 * is shared, data is reallocated. If reallocation fails, an error
1902 * is returned and original skb is not changed.
1904 * The result is skb with writable area skb->head...skb->tail
1905 * and at least @headroom of space at head.
1907 static inline int skb_cow(struct sk_buff
*skb
, unsigned int headroom
)
1909 return __skb_cow(skb
, headroom
, skb_cloned(skb
));
1913 * skb_cow_head - skb_cow but only making the head writable
1914 * @skb: buffer to cow
1915 * @headroom: needed headroom
1917 * This function is identical to skb_cow except that we replace the
1918 * skb_cloned check by skb_header_cloned. It should be used when
1919 * you only need to push on some header and do not need to modify
1922 static inline int skb_cow_head(struct sk_buff
*skb
, unsigned int headroom
)
1924 return __skb_cow(skb
, headroom
, skb_header_cloned(skb
));
1928 * skb_padto - pad an skbuff up to a minimal size
1929 * @skb: buffer to pad
1930 * @len: minimal length
1932 * Pads up a buffer to ensure the trailing bytes exist and are
1933 * blanked. If the buffer already contains sufficient data it
1934 * is untouched. Otherwise it is extended. Returns zero on
1935 * success. The skb is freed on error.
1938 static inline int skb_padto(struct sk_buff
*skb
, unsigned int len
)
1940 unsigned int size
= skb
->len
;
1941 if (likely(size
>= len
))
1943 return skb_pad(skb
, len
- size
);
1946 static inline int skb_add_data(struct sk_buff
*skb
,
1947 char __user
*from
, int copy
)
1949 const int off
= skb
->len
;
1951 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1953 __wsum csum
= csum_and_copy_from_user(from
, skb_put(skb
, copy
),
1956 skb
->csum
= csum_block_add(skb
->csum
, csum
, off
);
1959 } else if (!copy_from_user(skb_put(skb
, copy
), from
, copy
))
1962 __skb_trim(skb
, off
);
1966 static inline int skb_can_coalesce(struct sk_buff
*skb
, int i
,
1967 const struct page
*page
, int off
)
1970 const struct skb_frag_struct
*frag
= &skb_shinfo(skb
)->frags
[i
- 1];
1972 return page
== skb_frag_page(frag
) &&
1973 off
== frag
->page_offset
+ skb_frag_size(frag
);
1978 static inline int __skb_linearize(struct sk_buff
*skb
)
1980 return __pskb_pull_tail(skb
, skb
->data_len
) ? 0 : -ENOMEM
;
1984 * skb_linearize - convert paged skb to linear one
1985 * @skb: buffer to linarize
1987 * If there is no free memory -ENOMEM is returned, otherwise zero
1988 * is returned and the old skb data released.
1990 static inline int skb_linearize(struct sk_buff
*skb
)
1992 return skb_is_nonlinear(skb
) ? __skb_linearize(skb
) : 0;
1996 * skb_linearize_cow - make sure skb is linear and writable
1997 * @skb: buffer to process
1999 * If there is no free memory -ENOMEM is returned, otherwise zero
2000 * is returned and the old skb data released.
2002 static inline int skb_linearize_cow(struct sk_buff
*skb
)
2004 return skb_is_nonlinear(skb
) || skb_cloned(skb
) ?
2005 __skb_linearize(skb
) : 0;
2009 * skb_postpull_rcsum - update checksum for received skb after pull
2010 * @skb: buffer to update
2011 * @start: start of data before pull
2012 * @len: length of data pulled
2014 * After doing a pull on a received packet, you need to call this to
2015 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
2016 * CHECKSUM_NONE so that it can be recomputed from scratch.
2019 static inline void skb_postpull_rcsum(struct sk_buff
*skb
,
2020 const void *start
, unsigned int len
)
2022 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2023 skb
->csum
= csum_sub(skb
->csum
, csum_partial(start
, len
, 0));
2026 unsigned char *skb_pull_rcsum(struct sk_buff
*skb
, unsigned int len
);
2029 * pskb_trim_rcsum - trim received skb and update checksum
2030 * @skb: buffer to trim
2033 * This is exactly the same as pskb_trim except that it ensures the
2034 * checksum of received packets are still valid after the operation.
2037 static inline int pskb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
2039 if (likely(len
>= skb
->len
))
2041 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2042 skb
->ip_summed
= CHECKSUM_NONE
;
2043 return __pskb_trim(skb
, len
);
2046 #define skb_queue_walk(queue, skb) \
2047 for (skb = (queue)->next; \
2048 skb != (struct sk_buff *)(queue); \
2051 #define skb_queue_walk_safe(queue, skb, tmp) \
2052 for (skb = (queue)->next, tmp = skb->next; \
2053 skb != (struct sk_buff *)(queue); \
2054 skb = tmp, tmp = skb->next)
2056 #define skb_queue_walk_from(queue, skb) \
2057 for (; skb != (struct sk_buff *)(queue); \
2060 #define skb_queue_walk_from_safe(queue, skb, tmp) \
2061 for (tmp = skb->next; \
2062 skb != (struct sk_buff *)(queue); \
2063 skb = tmp, tmp = skb->next)
2065 #define skb_queue_reverse_walk(queue, skb) \
2066 for (skb = (queue)->prev; \
2067 skb != (struct sk_buff *)(queue); \
2070 #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
2071 for (skb = (queue)->prev, tmp = skb->prev; \
2072 skb != (struct sk_buff *)(queue); \
2073 skb = tmp, tmp = skb->prev)
2075 #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
2076 for (tmp = skb->prev; \
2077 skb != (struct sk_buff *)(queue); \
2078 skb = tmp, tmp = skb->prev)
2080 static inline bool skb_has_frag_list(const struct sk_buff
*skb
)
2082 return skb_shinfo(skb
)->frag_list
!= NULL
;
2085 static inline void skb_frag_list_init(struct sk_buff
*skb
)
2087 skb_shinfo(skb
)->frag_list
= NULL
;
2090 static inline void skb_frag_add_head(struct sk_buff
*skb
, struct sk_buff
*frag
)
2092 frag
->next
= skb_shinfo(skb
)->frag_list
;
2093 skb_shinfo(skb
)->frag_list
= frag
;
2096 #define skb_walk_frags(skb, iter) \
2097 for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
2099 extern struct sk_buff
*__skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2100 int *peeked
, int *off
, int *err
);
2101 extern struct sk_buff
*skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2102 int noblock
, int *err
);
2103 extern unsigned int datagram_poll(struct file
*file
, struct socket
*sock
,
2104 struct poll_table_struct
*wait
);
2105 extern int skb_copy_datagram_iovec(const struct sk_buff
*from
,
2106 int offset
, struct iovec
*to
,
2108 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff
*skb
,
2111 extern int skb_copy_datagram_from_iovec(struct sk_buff
*skb
,
2113 const struct iovec
*from
,
2116 extern int skb_copy_datagram_const_iovec(const struct sk_buff
*from
,
2118 const struct iovec
*to
,
2121 extern void skb_free_datagram(struct sock
*sk
, struct sk_buff
*skb
);
2122 extern void skb_free_datagram_locked(struct sock
*sk
,
2123 struct sk_buff
*skb
);
2124 extern int skb_kill_datagram(struct sock
*sk
, struct sk_buff
*skb
,
2125 unsigned int flags
);
2126 extern __wsum
skb_checksum(const struct sk_buff
*skb
, int offset
,
2127 int len
, __wsum csum
);
2128 extern int skb_copy_bits(const struct sk_buff
*skb
, int offset
,
2130 extern int skb_store_bits(struct sk_buff
*skb
, int offset
,
2131 const void *from
, int len
);
2132 extern __wsum
skb_copy_and_csum_bits(const struct sk_buff
*skb
,
2133 int offset
, u8
*to
, int len
,
2135 extern int skb_splice_bits(struct sk_buff
*skb
,
2136 unsigned int offset
,
2137 struct pipe_inode_info
*pipe
,
2139 unsigned int flags
);
2140 extern void skb_copy_and_csum_dev(const struct sk_buff
*skb
, u8
*to
);
2141 extern void skb_split(struct sk_buff
*skb
,
2142 struct sk_buff
*skb1
, const u32 len
);
2143 extern int skb_shift(struct sk_buff
*tgt
, struct sk_buff
*skb
,
2146 extern struct sk_buff
*skb_segment(struct sk_buff
*skb
,
2147 netdev_features_t features
);
2149 static inline void *skb_header_pointer(const struct sk_buff
*skb
, int offset
,
2150 int len
, void *buffer
)
2152 int hlen
= skb_headlen(skb
);
2154 if (hlen
- offset
>= len
)
2155 return skb
->data
+ offset
;
2157 if (skb_copy_bits(skb
, offset
, buffer
, len
) < 0)
2163 static inline void skb_copy_from_linear_data(const struct sk_buff
*skb
,
2165 const unsigned int len
)
2167 memcpy(to
, skb
->data
, len
);
2170 static inline void skb_copy_from_linear_data_offset(const struct sk_buff
*skb
,
2171 const int offset
, void *to
,
2172 const unsigned int len
)
2174 memcpy(to
, skb
->data
+ offset
, len
);
2177 static inline void skb_copy_to_linear_data(struct sk_buff
*skb
,
2179 const unsigned int len
)
2181 memcpy(skb
->data
, from
, len
);
2184 static inline void skb_copy_to_linear_data_offset(struct sk_buff
*skb
,
2187 const unsigned int len
)
2189 memcpy(skb
->data
+ offset
, from
, len
);
2192 extern void skb_init(void);
2194 static inline ktime_t
skb_get_ktime(const struct sk_buff
*skb
)
2200 * skb_get_timestamp - get timestamp from a skb
2201 * @skb: skb to get stamp from
2202 * @stamp: pointer to struct timeval to store stamp in
2204 * Timestamps are stored in the skb as offsets to a base timestamp.
2205 * This function converts the offset back to a struct timeval and stores
2208 static inline void skb_get_timestamp(const struct sk_buff
*skb
,
2209 struct timeval
*stamp
)
2211 *stamp
= ktime_to_timeval(skb
->tstamp
);
2214 static inline void skb_get_timestampns(const struct sk_buff
*skb
,
2215 struct timespec
*stamp
)
2217 *stamp
= ktime_to_timespec(skb
->tstamp
);
2220 static inline void __net_timestamp(struct sk_buff
*skb
)
2222 skb
->tstamp
= ktime_get_real();
2225 static inline ktime_t
net_timedelta(ktime_t t
)
2227 return ktime_sub(ktime_get_real(), t
);
2230 static inline ktime_t
net_invalid_timestamp(void)
2232 return ktime_set(0, 0);
2235 extern void skb_timestamping_init(void);
2237 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
2239 extern void skb_clone_tx_timestamp(struct sk_buff
*skb
);
2240 extern bool skb_defer_rx_timestamp(struct sk_buff
*skb
);
2242 #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
2244 static inline void skb_clone_tx_timestamp(struct sk_buff
*skb
)
2248 static inline bool skb_defer_rx_timestamp(struct sk_buff
*skb
)
2253 #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
2256 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
2258 * PHY drivers may accept clones of transmitted packets for
2259 * timestamping via their phy_driver.txtstamp method. These drivers
2260 * must call this function to return the skb back to the stack, with
2261 * or without a timestamp.
2263 * @skb: clone of the the original outgoing packet
2264 * @hwtstamps: hardware time stamps, may be NULL if not available
2267 void skb_complete_tx_timestamp(struct sk_buff
*skb
,
2268 struct skb_shared_hwtstamps
*hwtstamps
);
2271 * skb_tstamp_tx - queue clone of skb with send time stamps
2272 * @orig_skb: the original outgoing packet
2273 * @hwtstamps: hardware time stamps, may be NULL if not available
2275 * If the skb has a socket associated, then this function clones the
2276 * skb (thus sharing the actual data and optional structures), stores
2277 * the optional hardware time stamping information (if non NULL) or
2278 * generates a software time stamp (otherwise), then queues the clone
2279 * to the error queue of the socket. Errors are silently ignored.
2281 extern void skb_tstamp_tx(struct sk_buff
*orig_skb
,
2282 struct skb_shared_hwtstamps
*hwtstamps
);
2284 static inline void sw_tx_timestamp(struct sk_buff
*skb
)
2286 if (skb_shinfo(skb
)->tx_flags
& SKBTX_SW_TSTAMP
&&
2287 !(skb_shinfo(skb
)->tx_flags
& SKBTX_IN_PROGRESS
))
2288 skb_tstamp_tx(skb
, NULL
);
2292 * skb_tx_timestamp() - Driver hook for transmit timestamping
2294 * Ethernet MAC Drivers should call this function in their hard_xmit()
2295 * function immediately before giving the sk_buff to the MAC hardware.
2297 * @skb: A socket buffer.
2299 static inline void skb_tx_timestamp(struct sk_buff
*skb
)
2301 skb_clone_tx_timestamp(skb
);
2302 sw_tx_timestamp(skb
);
2306 * skb_complete_wifi_ack - deliver skb with wifi status
2308 * @skb: the original outgoing packet
2309 * @acked: ack status
2312 void skb_complete_wifi_ack(struct sk_buff
*skb
, bool acked
);
2314 extern __sum16
__skb_checksum_complete_head(struct sk_buff
*skb
, int len
);
2315 extern __sum16
__skb_checksum_complete(struct sk_buff
*skb
);
2317 static inline int skb_csum_unnecessary(const struct sk_buff
*skb
)
2319 return skb
->ip_summed
& CHECKSUM_UNNECESSARY
;
2323 * skb_checksum_complete - Calculate checksum of an entire packet
2324 * @skb: packet to process
2326 * This function calculates the checksum over the entire packet plus
2327 * the value of skb->csum. The latter can be used to supply the
2328 * checksum of a pseudo header as used by TCP/UDP. It returns the
2331 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
2332 * this function can be used to verify that checksum on received
2333 * packets. In that case the function should return zero if the
2334 * checksum is correct. In particular, this function will return zero
2335 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
2336 * hardware has already verified the correctness of the checksum.
2338 static inline __sum16
skb_checksum_complete(struct sk_buff
*skb
)
2340 return skb_csum_unnecessary(skb
) ?
2341 0 : __skb_checksum_complete(skb
);
2344 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2345 extern void nf_conntrack_destroy(struct nf_conntrack
*nfct
);
2346 static inline void nf_conntrack_put(struct nf_conntrack
*nfct
)
2348 if (nfct
&& atomic_dec_and_test(&nfct
->use
))
2349 nf_conntrack_destroy(nfct
);
2351 static inline void nf_conntrack_get(struct nf_conntrack
*nfct
)
2354 atomic_inc(&nfct
->use
);
2357 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2358 static inline void nf_conntrack_get_reasm(struct sk_buff
*skb
)
2361 atomic_inc(&skb
->users
);
2363 static inline void nf_conntrack_put_reasm(struct sk_buff
*skb
)
2369 #ifdef CONFIG_BRIDGE_NETFILTER
2370 static inline void nf_bridge_put(struct nf_bridge_info
*nf_bridge
)
2372 if (nf_bridge
&& atomic_dec_and_test(&nf_bridge
->use
))
2375 static inline void nf_bridge_get(struct nf_bridge_info
*nf_bridge
)
2378 atomic_inc(&nf_bridge
->use
);
2380 #endif /* CONFIG_BRIDGE_NETFILTER */
2381 static inline void nf_reset(struct sk_buff
*skb
)
2383 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2384 nf_conntrack_put(skb
->nfct
);
2387 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2388 nf_conntrack_put_reasm(skb
->nfct_reasm
);
2389 skb
->nfct_reasm
= NULL
;
2391 #ifdef CONFIG_BRIDGE_NETFILTER
2392 nf_bridge_put(skb
->nf_bridge
);
2393 skb
->nf_bridge
= NULL
;
2397 /* Note: This doesn't put any conntrack and bridge info in dst. */
2398 static inline void __nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2400 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2401 dst
->nfct
= src
->nfct
;
2402 nf_conntrack_get(src
->nfct
);
2403 dst
->nfctinfo
= src
->nfctinfo
;
2405 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2406 dst
->nfct_reasm
= src
->nfct_reasm
;
2407 nf_conntrack_get_reasm(src
->nfct_reasm
);
2409 #ifdef CONFIG_BRIDGE_NETFILTER
2410 dst
->nf_bridge
= src
->nf_bridge
;
2411 nf_bridge_get(src
->nf_bridge
);
2415 static inline void nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2417 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2418 nf_conntrack_put(dst
->nfct
);
2420 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2421 nf_conntrack_put_reasm(dst
->nfct_reasm
);
2423 #ifdef CONFIG_BRIDGE_NETFILTER
2424 nf_bridge_put(dst
->nf_bridge
);
2426 __nf_copy(dst
, src
);
2429 #ifdef CONFIG_NETWORK_SECMARK
2430 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2432 to
->secmark
= from
->secmark
;
2435 static inline void skb_init_secmark(struct sk_buff
*skb
)
2440 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2443 static inline void skb_init_secmark(struct sk_buff
*skb
)
2447 static inline void skb_set_queue_mapping(struct sk_buff
*skb
, u16 queue_mapping
)
2449 skb
->queue_mapping
= queue_mapping
;
2452 static inline u16
skb_get_queue_mapping(const struct sk_buff
*skb
)
2454 return skb
->queue_mapping
;
2457 static inline void skb_copy_queue_mapping(struct sk_buff
*to
, const struct sk_buff
*from
)
2459 to
->queue_mapping
= from
->queue_mapping
;
2462 static inline void skb_record_rx_queue(struct sk_buff
*skb
, u16 rx_queue
)
2464 skb
->queue_mapping
= rx_queue
+ 1;
2467 static inline u16
skb_get_rx_queue(const struct sk_buff
*skb
)
2469 return skb
->queue_mapping
- 1;
2472 static inline bool skb_rx_queue_recorded(const struct sk_buff
*skb
)
2474 return skb
->queue_mapping
!= 0;
2477 extern u16
__skb_tx_hash(const struct net_device
*dev
,
2478 const struct sk_buff
*skb
,
2479 unsigned int num_tx_queues
);
2482 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2487 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2493 static inline bool skb_is_gso(const struct sk_buff
*skb
)
2495 return skb_shinfo(skb
)->gso_size
;
2498 static inline bool skb_is_gso_v6(const struct sk_buff
*skb
)
2500 return skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
;
2503 extern void __skb_warn_lro_forwarding(const struct sk_buff
*skb
);
2505 static inline bool skb_warn_if_lro(const struct sk_buff
*skb
)
2507 /* LRO sets gso_size but not gso_type, whereas if GSO is really
2508 * wanted then gso_type will be set. */
2509 const struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
2511 if (skb_is_nonlinear(skb
) && shinfo
->gso_size
!= 0 &&
2512 unlikely(shinfo
->gso_type
== 0)) {
2513 __skb_warn_lro_forwarding(skb
);
2519 static inline void skb_forward_csum(struct sk_buff
*skb
)
2521 /* Unfortunately we don't support this one. Any brave souls? */
2522 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2523 skb
->ip_summed
= CHECKSUM_NONE
;
2527 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
2528 * @skb: skb to check
2530 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
2531 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
2532 * use this helper, to document places where we make this assertion.
2534 static inline void skb_checksum_none_assert(const struct sk_buff
*skb
)
2537 BUG_ON(skb
->ip_summed
!= CHECKSUM_NONE
);
2541 bool skb_partial_csum_set(struct sk_buff
*skb
, u16 start
, u16 off
);
2543 static inline bool skb_is_recycleable(const struct sk_buff
*skb
, int skb_size
)
2545 if (irqs_disabled())
2548 if (skb_shinfo(skb
)->tx_flags
& SKBTX_DEV_ZEROCOPY
)
2551 if (skb_is_nonlinear(skb
) || skb
->fclone
!= SKB_FCLONE_UNAVAILABLE
)
2554 skb_size
= SKB_DATA_ALIGN(skb_size
+ NET_SKB_PAD
);
2555 if (skb_end_pointer(skb
) - skb
->head
< skb_size
)
2558 if (skb_shared(skb
) || skb_cloned(skb
))
2563 #endif /* __KERNEL__ */
2564 #endif /* _LINUX_SKBUFF_H */