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
{
122 struct net_device
*physindev
;
123 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;
474 /* 8/10 bit hole (depending on ndisc_nodetype presence) */
475 kmemcheck_bitfield_end(flags2
);
477 #ifdef CONFIG_NET_DMA
478 dma_cookie_t dma_cookie
;
480 #ifdef CONFIG_NETWORK_SECMARK
489 sk_buff_data_t transport_header
;
490 sk_buff_data_t network_header
;
491 sk_buff_data_t mac_header
;
492 /* These elements must be at the end, see alloc_skb() for details. */
497 unsigned int truesize
;
503 * Handling routines are only of interest to the kernel
505 #include <linux/slab.h>
509 * skb might have a dst pointer attached, refcounted or not.
510 * _skb_refdst low order bit is set if refcount was _not_ taken
512 #define SKB_DST_NOREF 1UL
513 #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
516 * skb_dst - returns skb dst_entry
519 * Returns skb dst_entry, regardless of reference taken or not.
521 static inline struct dst_entry
*skb_dst(const struct sk_buff
*skb
)
523 /* If refdst was not refcounted, check we still are in a
524 * rcu_read_lock section
526 WARN_ON((skb
->_skb_refdst
& SKB_DST_NOREF
) &&
527 !rcu_read_lock_held() &&
528 !rcu_read_lock_bh_held());
529 return (struct dst_entry
*)(skb
->_skb_refdst
& SKB_DST_PTRMASK
);
533 * skb_dst_set - sets skb dst
537 * Sets skb dst, assuming a reference was taken on dst and should
538 * be released by skb_dst_drop()
540 static inline void skb_dst_set(struct sk_buff
*skb
, struct dst_entry
*dst
)
542 skb
->_skb_refdst
= (unsigned long)dst
;
545 extern void skb_dst_set_noref(struct sk_buff
*skb
, struct dst_entry
*dst
);
548 * skb_dst_is_noref - Test if skb dst isn't refcounted
551 static inline bool skb_dst_is_noref(const struct sk_buff
*skb
)
553 return (skb
->_skb_refdst
& SKB_DST_NOREF
) && skb_dst(skb
);
556 static inline struct rtable
*skb_rtable(const struct sk_buff
*skb
)
558 return (struct rtable
*)skb_dst(skb
);
561 extern void kfree_skb(struct sk_buff
*skb
);
562 extern void consume_skb(struct sk_buff
*skb
);
563 extern void __kfree_skb(struct sk_buff
*skb
);
564 extern struct kmem_cache
*skbuff_head_cache
;
566 extern void kfree_skb_partial(struct sk_buff
*skb
, bool head_stolen
);
567 extern bool skb_try_coalesce(struct sk_buff
*to
, struct sk_buff
*from
,
568 bool *fragstolen
, int *delta_truesize
);
570 extern struct sk_buff
*__alloc_skb(unsigned int size
,
571 gfp_t priority
, int fclone
, int node
);
572 extern struct sk_buff
*build_skb(void *data
, unsigned int frag_size
);
573 static inline struct sk_buff
*alloc_skb(unsigned int size
,
576 return __alloc_skb(size
, priority
, 0, NUMA_NO_NODE
);
579 static inline struct sk_buff
*alloc_skb_fclone(unsigned int size
,
582 return __alloc_skb(size
, priority
, 1, NUMA_NO_NODE
);
585 extern void skb_recycle(struct sk_buff
*skb
);
586 extern bool skb_recycle_check(struct sk_buff
*skb
, int skb_size
);
588 extern struct sk_buff
*skb_morph(struct sk_buff
*dst
, struct sk_buff
*src
);
589 extern int skb_copy_ubufs(struct sk_buff
*skb
, gfp_t gfp_mask
);
590 extern struct sk_buff
*skb_clone(struct sk_buff
*skb
,
592 extern struct sk_buff
*skb_copy(const struct sk_buff
*skb
,
594 extern struct sk_buff
*__pskb_copy(struct sk_buff
*skb
,
595 int headroom
, gfp_t gfp_mask
);
597 extern int pskb_expand_head(struct sk_buff
*skb
,
598 int nhead
, int ntail
,
600 extern struct sk_buff
*skb_realloc_headroom(struct sk_buff
*skb
,
601 unsigned int headroom
);
602 extern struct sk_buff
*skb_copy_expand(const struct sk_buff
*skb
,
603 int newheadroom
, int newtailroom
,
605 extern int skb_to_sgvec(struct sk_buff
*skb
,
606 struct scatterlist
*sg
, int offset
,
608 extern int skb_cow_data(struct sk_buff
*skb
, int tailbits
,
609 struct sk_buff
**trailer
);
610 extern int skb_pad(struct sk_buff
*skb
, int pad
);
611 #define dev_kfree_skb(a) consume_skb(a)
613 extern int skb_append_datato_frags(struct sock
*sk
, struct sk_buff
*skb
,
614 int getfrag(void *from
, char *to
, int offset
,
615 int len
,int odd
, struct sk_buff
*skb
),
616 void *from
, int length
);
618 struct skb_seq_state
{
622 __u32 stepped_offset
;
623 struct sk_buff
*root_skb
;
624 struct sk_buff
*cur_skb
;
628 extern void skb_prepare_seq_read(struct sk_buff
*skb
,
629 unsigned int from
, unsigned int to
,
630 struct skb_seq_state
*st
);
631 extern unsigned int skb_seq_read(unsigned int consumed
, const u8
**data
,
632 struct skb_seq_state
*st
);
633 extern void skb_abort_seq_read(struct skb_seq_state
*st
);
635 extern unsigned int skb_find_text(struct sk_buff
*skb
, unsigned int from
,
636 unsigned int to
, struct ts_config
*config
,
637 struct ts_state
*state
);
639 extern void __skb_get_rxhash(struct sk_buff
*skb
);
640 static inline __u32
skb_get_rxhash(struct sk_buff
*skb
)
643 __skb_get_rxhash(skb
);
648 #ifdef NET_SKBUFF_DATA_USES_OFFSET
649 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
651 return skb
->head
+ skb
->end
;
654 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
659 static inline unsigned char *skb_end_pointer(const struct sk_buff
*skb
)
664 static inline unsigned int skb_end_offset(const struct sk_buff
*skb
)
666 return skb
->end
- skb
->head
;
671 #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
673 static inline struct skb_shared_hwtstamps
*skb_hwtstamps(struct sk_buff
*skb
)
675 return &skb_shinfo(skb
)->hwtstamps
;
679 * skb_queue_empty - check if a queue is empty
682 * Returns true if the queue is empty, false otherwise.
684 static inline int skb_queue_empty(const struct sk_buff_head
*list
)
686 return list
->next
== (struct sk_buff
*)list
;
690 * skb_queue_is_last - check if skb is the last entry in the queue
694 * Returns true if @skb is the last buffer on the list.
696 static inline bool skb_queue_is_last(const struct sk_buff_head
*list
,
697 const struct sk_buff
*skb
)
699 return skb
->next
== (struct sk_buff
*)list
;
703 * skb_queue_is_first - check if skb is the first entry in the queue
707 * Returns true if @skb is the first buffer on the list.
709 static inline bool skb_queue_is_first(const struct sk_buff_head
*list
,
710 const struct sk_buff
*skb
)
712 return skb
->prev
== (struct sk_buff
*)list
;
716 * skb_queue_next - return the next packet in the queue
718 * @skb: current buffer
720 * Return the next packet in @list after @skb. It is only valid to
721 * call this if skb_queue_is_last() evaluates to false.
723 static inline struct sk_buff
*skb_queue_next(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_last(list
, skb
));
734 * skb_queue_prev - return the prev packet in the queue
736 * @skb: current buffer
738 * Return the prev packet in @list before @skb. It is only valid to
739 * call this if skb_queue_is_first() evaluates to false.
741 static inline struct sk_buff
*skb_queue_prev(const struct sk_buff_head
*list
,
742 const struct sk_buff
*skb
)
744 /* This BUG_ON may seem severe, but if we just return then we
745 * are going to dereference garbage.
747 BUG_ON(skb_queue_is_first(list
, skb
));
752 * skb_get - reference buffer
753 * @skb: buffer to reference
755 * Makes another reference to a socket buffer and returns a pointer
758 static inline struct sk_buff
*skb_get(struct sk_buff
*skb
)
760 atomic_inc(&skb
->users
);
765 * If users == 1, we are the only owner and are can avoid redundant
770 * skb_cloned - is the buffer a clone
771 * @skb: buffer to check
773 * Returns true if the buffer was generated with skb_clone() and is
774 * one of multiple shared copies of the buffer. Cloned buffers are
775 * shared data so must not be written to under normal circumstances.
777 static inline int skb_cloned(const struct sk_buff
*skb
)
779 return skb
->cloned
&&
780 (atomic_read(&skb_shinfo(skb
)->dataref
) & SKB_DATAREF_MASK
) != 1;
784 * skb_header_cloned - is the header a clone
785 * @skb: buffer to check
787 * Returns true if modifying the header part of the buffer requires
788 * the data to be copied.
790 static inline int skb_header_cloned(const struct sk_buff
*skb
)
797 dataref
= atomic_read(&skb_shinfo(skb
)->dataref
);
798 dataref
= (dataref
& SKB_DATAREF_MASK
) - (dataref
>> SKB_DATAREF_SHIFT
);
803 * skb_header_release - release reference to header
804 * @skb: buffer to operate on
806 * Drop a reference to the header part of the buffer. This is done
807 * by acquiring a payload reference. You must not read from the header
808 * part of skb->data after this.
810 static inline void skb_header_release(struct sk_buff
*skb
)
814 atomic_add(1 << SKB_DATAREF_SHIFT
, &skb_shinfo(skb
)->dataref
);
818 * skb_shared - is the buffer shared
819 * @skb: buffer to check
821 * Returns true if more than one person has a reference to this
824 static inline int skb_shared(const struct sk_buff
*skb
)
826 return atomic_read(&skb
->users
) != 1;
830 * skb_share_check - check if buffer is shared and if so clone it
831 * @skb: buffer to check
832 * @pri: priority for memory allocation
834 * If the buffer is shared the buffer is cloned and the old copy
835 * drops a reference. A new clone with a single reference is returned.
836 * If the buffer is not shared the original buffer is returned. When
837 * being called from interrupt status or with spinlocks held pri must
840 * NULL is returned on a memory allocation failure.
842 static inline struct sk_buff
*skb_share_check(struct sk_buff
*skb
,
845 might_sleep_if(pri
& __GFP_WAIT
);
846 if (skb_shared(skb
)) {
847 struct sk_buff
*nskb
= skb_clone(skb
, pri
);
855 * Copy shared buffers into a new sk_buff. We effectively do COW on
856 * packets to handle cases where we have a local reader and forward
857 * and a couple of other messy ones. The normal one is tcpdumping
858 * a packet thats being forwarded.
862 * skb_unshare - make a copy of a shared buffer
863 * @skb: buffer to check
864 * @pri: priority for memory allocation
866 * If the socket buffer is a clone then this function creates a new
867 * copy of the data, drops a reference count on the old copy and returns
868 * the new copy with the reference count at 1. If the buffer is not a clone
869 * the original buffer is returned. When called with a spinlock held or
870 * from interrupt state @pri must be %GFP_ATOMIC
872 * %NULL is returned on a memory allocation failure.
874 static inline struct sk_buff
*skb_unshare(struct sk_buff
*skb
,
877 might_sleep_if(pri
& __GFP_WAIT
);
878 if (skb_cloned(skb
)) {
879 struct sk_buff
*nskb
= skb_copy(skb
, pri
);
880 kfree_skb(skb
); /* Free our shared copy */
887 * skb_peek - peek at the head of an &sk_buff_head
888 * @list_: list to peek at
890 * Peek an &sk_buff. Unlike most other operations you _MUST_
891 * be careful with this one. A peek leaves the buffer on the
892 * list and someone else may run off with it. You must hold
893 * the appropriate locks or have a private queue to do this.
895 * Returns %NULL for an empty list or a pointer to the head element.
896 * The reference count is not incremented and the reference is therefore
897 * volatile. Use with caution.
899 static inline struct sk_buff
*skb_peek(const struct sk_buff_head
*list_
)
901 struct sk_buff
*skb
= list_
->next
;
903 if (skb
== (struct sk_buff
*)list_
)
909 * skb_peek_next - peek skb following the given one from a queue
910 * @skb: skb to start from
911 * @list_: list to peek at
913 * Returns %NULL when the end of the list is met or a pointer to the
914 * next element. The reference count is not incremented and the
915 * reference is therefore volatile. Use with caution.
917 static inline struct sk_buff
*skb_peek_next(struct sk_buff
*skb
,
918 const struct sk_buff_head
*list_
)
920 struct sk_buff
*next
= skb
->next
;
922 if (next
== (struct sk_buff
*)list_
)
928 * skb_peek_tail - peek at the tail of an &sk_buff_head
929 * @list_: list to peek at
931 * Peek an &sk_buff. Unlike most other operations you _MUST_
932 * be careful with this one. A peek leaves the buffer on the
933 * list and someone else may run off with it. You must hold
934 * the appropriate locks or have a private queue to do this.
936 * Returns %NULL for an empty list or a pointer to the tail element.
937 * The reference count is not incremented and the reference is therefore
938 * volatile. Use with caution.
940 static inline struct sk_buff
*skb_peek_tail(const struct sk_buff_head
*list_
)
942 struct sk_buff
*skb
= list_
->prev
;
944 if (skb
== (struct sk_buff
*)list_
)
951 * skb_queue_len - get queue length
952 * @list_: list to measure
954 * Return the length of an &sk_buff queue.
956 static inline __u32
skb_queue_len(const struct sk_buff_head
*list_
)
962 * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
963 * @list: queue to initialize
965 * This initializes only the list and queue length aspects of
966 * an sk_buff_head object. This allows to initialize the list
967 * aspects of an sk_buff_head without reinitializing things like
968 * the spinlock. It can also be used for on-stack sk_buff_head
969 * objects where the spinlock is known to not be used.
971 static inline void __skb_queue_head_init(struct sk_buff_head
*list
)
973 list
->prev
= list
->next
= (struct sk_buff
*)list
;
978 * This function creates a split out lock class for each invocation;
979 * this is needed for now since a whole lot of users of the skb-queue
980 * infrastructure in drivers have different locking usage (in hardirq)
981 * than the networking core (in softirq only). In the long run either the
982 * network layer or drivers should need annotation to consolidate the
983 * main types of usage into 3 classes.
985 static inline void skb_queue_head_init(struct sk_buff_head
*list
)
987 spin_lock_init(&list
->lock
);
988 __skb_queue_head_init(list
);
991 static inline void skb_queue_head_init_class(struct sk_buff_head
*list
,
992 struct lock_class_key
*class)
994 skb_queue_head_init(list
);
995 lockdep_set_class(&list
->lock
, class);
999 * Insert an sk_buff on a list.
1001 * The "__skb_xxxx()" functions are the non-atomic ones that
1002 * can only be called with interrupts disabled.
1004 extern void skb_insert(struct sk_buff
*old
, struct sk_buff
*newsk
, struct sk_buff_head
*list
);
1005 static inline void __skb_insert(struct sk_buff
*newsk
,
1006 struct sk_buff
*prev
, struct sk_buff
*next
,
1007 struct sk_buff_head
*list
)
1011 next
->prev
= prev
->next
= newsk
;
1015 static inline void __skb_queue_splice(const struct sk_buff_head
*list
,
1016 struct sk_buff
*prev
,
1017 struct sk_buff
*next
)
1019 struct sk_buff
*first
= list
->next
;
1020 struct sk_buff
*last
= list
->prev
;
1030 * skb_queue_splice - join two skb lists, this is designed for stacks
1031 * @list: the new list to add
1032 * @head: the place to add it in the first list
1034 static inline void skb_queue_splice(const struct sk_buff_head
*list
,
1035 struct sk_buff_head
*head
)
1037 if (!skb_queue_empty(list
)) {
1038 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1039 head
->qlen
+= list
->qlen
;
1044 * skb_queue_splice_init - join two skb lists and reinitialise the emptied list
1045 * @list: the new list to add
1046 * @head: the place to add it in the first list
1048 * The list at @list is reinitialised
1050 static inline void skb_queue_splice_init(struct sk_buff_head
*list
,
1051 struct sk_buff_head
*head
)
1053 if (!skb_queue_empty(list
)) {
1054 __skb_queue_splice(list
, (struct sk_buff
*) head
, head
->next
);
1055 head
->qlen
+= list
->qlen
;
1056 __skb_queue_head_init(list
);
1061 * skb_queue_splice_tail - join two skb lists, each list being a queue
1062 * @list: the new list to add
1063 * @head: the place to add it in the first list
1065 static inline void skb_queue_splice_tail(const struct sk_buff_head
*list
,
1066 struct sk_buff_head
*head
)
1068 if (!skb_queue_empty(list
)) {
1069 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1070 head
->qlen
+= list
->qlen
;
1075 * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list
1076 * @list: the new list to add
1077 * @head: the place to add it in the first list
1079 * Each of the lists is a queue.
1080 * The list at @list is reinitialised
1082 static inline void skb_queue_splice_tail_init(struct sk_buff_head
*list
,
1083 struct sk_buff_head
*head
)
1085 if (!skb_queue_empty(list
)) {
1086 __skb_queue_splice(list
, head
->prev
, (struct sk_buff
*) head
);
1087 head
->qlen
+= list
->qlen
;
1088 __skb_queue_head_init(list
);
1093 * __skb_queue_after - queue a buffer at the list head
1094 * @list: list to use
1095 * @prev: place after this buffer
1096 * @newsk: buffer to queue
1098 * Queue a buffer int the middle of a list. This function takes no locks
1099 * and you must therefore hold required locks before calling it.
1101 * A buffer cannot be placed on two lists at the same time.
1103 static inline void __skb_queue_after(struct sk_buff_head
*list
,
1104 struct sk_buff
*prev
,
1105 struct sk_buff
*newsk
)
1107 __skb_insert(newsk
, prev
, prev
->next
, list
);
1110 extern void skb_append(struct sk_buff
*old
, struct sk_buff
*newsk
,
1111 struct sk_buff_head
*list
);
1113 static inline void __skb_queue_before(struct sk_buff_head
*list
,
1114 struct sk_buff
*next
,
1115 struct sk_buff
*newsk
)
1117 __skb_insert(newsk
, next
->prev
, next
, list
);
1121 * __skb_queue_head - queue a buffer at the list head
1122 * @list: list to use
1123 * @newsk: buffer to queue
1125 * Queue a buffer at the start of a list. This function takes no locks
1126 * and you must therefore hold required locks before calling it.
1128 * A buffer cannot be placed on two lists at the same time.
1130 extern void skb_queue_head(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1131 static inline void __skb_queue_head(struct sk_buff_head
*list
,
1132 struct sk_buff
*newsk
)
1134 __skb_queue_after(list
, (struct sk_buff
*)list
, newsk
);
1138 * __skb_queue_tail - queue a buffer at the list tail
1139 * @list: list to use
1140 * @newsk: buffer to queue
1142 * Queue a buffer at the end of a list. This function takes no locks
1143 * and you must therefore hold required locks before calling it.
1145 * A buffer cannot be placed on two lists at the same time.
1147 extern void skb_queue_tail(struct sk_buff_head
*list
, struct sk_buff
*newsk
);
1148 static inline void __skb_queue_tail(struct sk_buff_head
*list
,
1149 struct sk_buff
*newsk
)
1151 __skb_queue_before(list
, (struct sk_buff
*)list
, newsk
);
1155 * remove sk_buff from list. _Must_ be called atomically, and with
1158 extern void skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
);
1159 static inline void __skb_unlink(struct sk_buff
*skb
, struct sk_buff_head
*list
)
1161 struct sk_buff
*next
, *prev
;
1166 skb
->next
= skb
->prev
= NULL
;
1172 * __skb_dequeue - remove from the head of the queue
1173 * @list: list to dequeue from
1175 * Remove the head of the list. This function does not take any locks
1176 * so must be used with appropriate locks held only. The head item is
1177 * returned or %NULL if the list is empty.
1179 extern struct sk_buff
*skb_dequeue(struct sk_buff_head
*list
);
1180 static inline struct sk_buff
*__skb_dequeue(struct sk_buff_head
*list
)
1182 struct sk_buff
*skb
= skb_peek(list
);
1184 __skb_unlink(skb
, list
);
1189 * __skb_dequeue_tail - remove from the tail of the queue
1190 * @list: list to dequeue from
1192 * Remove the tail of the list. This function does not take any locks
1193 * so must be used with appropriate locks held only. The tail item is
1194 * returned or %NULL if the list is empty.
1196 extern struct sk_buff
*skb_dequeue_tail(struct sk_buff_head
*list
);
1197 static inline struct sk_buff
*__skb_dequeue_tail(struct sk_buff_head
*list
)
1199 struct sk_buff
*skb
= skb_peek_tail(list
);
1201 __skb_unlink(skb
, list
);
1206 static inline bool skb_is_nonlinear(const struct sk_buff
*skb
)
1208 return skb
->data_len
;
1211 static inline unsigned int skb_headlen(const struct sk_buff
*skb
)
1213 return skb
->len
- skb
->data_len
;
1216 static inline int skb_pagelen(const struct sk_buff
*skb
)
1220 for (i
= (int)skb_shinfo(skb
)->nr_frags
- 1; i
>= 0; i
--)
1221 len
+= skb_frag_size(&skb_shinfo(skb
)->frags
[i
]);
1222 return len
+ skb_headlen(skb
);
1226 * __skb_fill_page_desc - initialise a paged fragment in an skb
1227 * @skb: buffer containing fragment to be initialised
1228 * @i: paged fragment index to initialise
1229 * @page: the page to use for this fragment
1230 * @off: the offset to the data with @page
1231 * @size: the length of the data
1233 * Initialises the @i'th fragment of @skb to point to &size bytes at
1234 * offset @off within @page.
1236 * Does not take any additional reference on the fragment.
1238 static inline void __skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1239 struct page
*page
, int off
, int size
)
1241 skb_frag_t
*frag
= &skb_shinfo(skb
)->frags
[i
];
1243 frag
->page
.p
= page
;
1244 frag
->page_offset
= off
;
1245 skb_frag_size_set(frag
, size
);
1249 * skb_fill_page_desc - initialise a paged fragment in an skb
1250 * @skb: buffer containing fragment to be initialised
1251 * @i: paged fragment index to initialise
1252 * @page: the page to use for this fragment
1253 * @off: the offset to the data with @page
1254 * @size: the length of the data
1256 * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
1257 * @skb to point to &size bytes at offset @off within @page. In
1258 * addition updates @skb such that @i is the last fragment.
1260 * Does not take any additional reference on the fragment.
1262 static inline void skb_fill_page_desc(struct sk_buff
*skb
, int i
,
1263 struct page
*page
, int off
, int size
)
1265 __skb_fill_page_desc(skb
, i
, page
, off
, size
);
1266 skb_shinfo(skb
)->nr_frags
= i
+ 1;
1269 extern void skb_add_rx_frag(struct sk_buff
*skb
, int i
, struct page
*page
,
1270 int off
, int size
, unsigned int truesize
);
1272 #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
1273 #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb))
1274 #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
1276 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1277 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1279 return skb
->head
+ skb
->tail
;
1282 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1284 skb
->tail
= skb
->data
- skb
->head
;
1287 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1289 skb_reset_tail_pointer(skb
);
1290 skb
->tail
+= offset
;
1292 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1293 static inline unsigned char *skb_tail_pointer(const struct sk_buff
*skb
)
1298 static inline void skb_reset_tail_pointer(struct sk_buff
*skb
)
1300 skb
->tail
= skb
->data
;
1303 static inline void skb_set_tail_pointer(struct sk_buff
*skb
, const int offset
)
1305 skb
->tail
= skb
->data
+ offset
;
1308 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1311 * Add data to an sk_buff
1313 extern unsigned char *skb_put(struct sk_buff
*skb
, unsigned int len
);
1314 static inline unsigned char *__skb_put(struct sk_buff
*skb
, unsigned int len
)
1316 unsigned char *tmp
= skb_tail_pointer(skb
);
1317 SKB_LINEAR_ASSERT(skb
);
1323 extern unsigned char *skb_push(struct sk_buff
*skb
, unsigned int len
);
1324 static inline unsigned char *__skb_push(struct sk_buff
*skb
, unsigned int len
)
1331 extern unsigned char *skb_pull(struct sk_buff
*skb
, unsigned int len
);
1332 static inline unsigned char *__skb_pull(struct sk_buff
*skb
, unsigned int len
)
1335 BUG_ON(skb
->len
< skb
->data_len
);
1336 return skb
->data
+= len
;
1339 static inline unsigned char *skb_pull_inline(struct sk_buff
*skb
, unsigned int len
)
1341 return unlikely(len
> skb
->len
) ? NULL
: __skb_pull(skb
, len
);
1344 extern unsigned char *__pskb_pull_tail(struct sk_buff
*skb
, int delta
);
1346 static inline unsigned char *__pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1348 if (len
> skb_headlen(skb
) &&
1349 !__pskb_pull_tail(skb
, len
- skb_headlen(skb
)))
1352 return skb
->data
+= len
;
1355 static inline unsigned char *pskb_pull(struct sk_buff
*skb
, unsigned int len
)
1357 return unlikely(len
> skb
->len
) ? NULL
: __pskb_pull(skb
, len
);
1360 static inline int pskb_may_pull(struct sk_buff
*skb
, unsigned int len
)
1362 if (likely(len
<= skb_headlen(skb
)))
1364 if (unlikely(len
> skb
->len
))
1366 return __pskb_pull_tail(skb
, len
- skb_headlen(skb
)) != NULL
;
1370 * skb_headroom - bytes at buffer head
1371 * @skb: buffer to check
1373 * Return the number of bytes of free space at the head of an &sk_buff.
1375 static inline unsigned int skb_headroom(const struct sk_buff
*skb
)
1377 return skb
->data
- skb
->head
;
1381 * skb_tailroom - bytes at buffer end
1382 * @skb: buffer to check
1384 * Return the number of bytes of free space at the tail of an sk_buff
1386 static inline int skb_tailroom(const struct sk_buff
*skb
)
1388 return skb_is_nonlinear(skb
) ? 0 : skb
->end
- skb
->tail
;
1392 * skb_availroom - bytes at buffer end
1393 * @skb: buffer to check
1395 * Return the number of bytes of free space at the tail of an sk_buff
1396 * allocated by sk_stream_alloc()
1398 static inline int skb_availroom(const struct sk_buff
*skb
)
1400 return skb_is_nonlinear(skb
) ? 0 : skb
->avail_size
- skb
->len
;
1404 * skb_reserve - adjust headroom
1405 * @skb: buffer to alter
1406 * @len: bytes to move
1408 * Increase the headroom of an empty &sk_buff by reducing the tail
1409 * room. This is only allowed for an empty buffer.
1411 static inline void skb_reserve(struct sk_buff
*skb
, int len
)
1417 static inline void skb_reset_mac_len(struct sk_buff
*skb
)
1419 skb
->mac_len
= skb
->network_header
- skb
->mac_header
;
1422 #ifdef NET_SKBUFF_DATA_USES_OFFSET
1423 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1425 return skb
->head
+ skb
->transport_header
;
1428 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1430 skb
->transport_header
= skb
->data
- skb
->head
;
1433 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1436 skb_reset_transport_header(skb
);
1437 skb
->transport_header
+= offset
;
1440 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1442 return skb
->head
+ skb
->network_header
;
1445 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1447 skb
->network_header
= skb
->data
- skb
->head
;
1450 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1452 skb_reset_network_header(skb
);
1453 skb
->network_header
+= offset
;
1456 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1458 return skb
->head
+ skb
->mac_header
;
1461 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1463 return skb
->mac_header
!= ~0U;
1466 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1468 skb
->mac_header
= skb
->data
- skb
->head
;
1471 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1473 skb_reset_mac_header(skb
);
1474 skb
->mac_header
+= offset
;
1477 #else /* NET_SKBUFF_DATA_USES_OFFSET */
1479 static inline unsigned char *skb_transport_header(const struct sk_buff
*skb
)
1481 return skb
->transport_header
;
1484 static inline void skb_reset_transport_header(struct sk_buff
*skb
)
1486 skb
->transport_header
= skb
->data
;
1489 static inline void skb_set_transport_header(struct sk_buff
*skb
,
1492 skb
->transport_header
= skb
->data
+ offset
;
1495 static inline unsigned char *skb_network_header(const struct sk_buff
*skb
)
1497 return skb
->network_header
;
1500 static inline void skb_reset_network_header(struct sk_buff
*skb
)
1502 skb
->network_header
= skb
->data
;
1505 static inline void skb_set_network_header(struct sk_buff
*skb
, const int offset
)
1507 skb
->network_header
= skb
->data
+ offset
;
1510 static inline unsigned char *skb_mac_header(const struct sk_buff
*skb
)
1512 return skb
->mac_header
;
1515 static inline int skb_mac_header_was_set(const struct sk_buff
*skb
)
1517 return skb
->mac_header
!= NULL
;
1520 static inline void skb_reset_mac_header(struct sk_buff
*skb
)
1522 skb
->mac_header
= skb
->data
;
1525 static inline void skb_set_mac_header(struct sk_buff
*skb
, const int offset
)
1527 skb
->mac_header
= skb
->data
+ offset
;
1529 #endif /* NET_SKBUFF_DATA_USES_OFFSET */
1531 static inline void skb_mac_header_rebuild(struct sk_buff
*skb
)
1533 if (skb_mac_header_was_set(skb
)) {
1534 const unsigned char *old_mac
= skb_mac_header(skb
);
1536 skb_set_mac_header(skb
, -skb
->mac_len
);
1537 memmove(skb_mac_header(skb
), old_mac
, skb
->mac_len
);
1541 static inline int skb_checksum_start_offset(const struct sk_buff
*skb
)
1543 return skb
->csum_start
- skb_headroom(skb
);
1546 static inline int skb_transport_offset(const struct sk_buff
*skb
)
1548 return skb_transport_header(skb
) - skb
->data
;
1551 static inline u32
skb_network_header_len(const struct sk_buff
*skb
)
1553 return skb
->transport_header
- skb
->network_header
;
1556 static inline int skb_network_offset(const struct sk_buff
*skb
)
1558 return skb_network_header(skb
) - skb
->data
;
1561 static inline int pskb_network_may_pull(struct sk_buff
*skb
, unsigned int len
)
1563 return pskb_may_pull(skb
, skb_network_offset(skb
) + len
);
1567 * CPUs often take a performance hit when accessing unaligned memory
1568 * locations. The actual performance hit varies, it can be small if the
1569 * hardware handles it or large if we have to take an exception and fix it
1572 * Since an ethernet header is 14 bytes network drivers often end up with
1573 * the IP header at an unaligned offset. The IP header can be aligned by
1574 * shifting the start of the packet by 2 bytes. Drivers should do this
1577 * skb_reserve(skb, NET_IP_ALIGN);
1579 * The downside to this alignment of the IP header is that the DMA is now
1580 * unaligned. On some architectures the cost of an unaligned DMA is high
1581 * and this cost outweighs the gains made by aligning the IP header.
1583 * Since this trade off varies between architectures, we allow NET_IP_ALIGN
1586 #ifndef NET_IP_ALIGN
1587 #define NET_IP_ALIGN 2
1591 * The networking layer reserves some headroom in skb data (via
1592 * dev_alloc_skb). This is used to avoid having to reallocate skb data when
1593 * the header has to grow. In the default case, if the header has to grow
1594 * 32 bytes or less we avoid the reallocation.
1596 * Unfortunately this headroom changes the DMA alignment of the resulting
1597 * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
1598 * on some architectures. An architecture can override this value,
1599 * perhaps setting it to a cacheline in size (since that will maintain
1600 * cacheline alignment of the DMA). It must be a power of 2.
1602 * Various parts of the networking layer expect at least 32 bytes of
1603 * headroom, you should not reduce this.
1605 * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
1606 * to reduce average number of cache lines per packet.
1607 * get_rps_cpus() for example only access one 64 bytes aligned block :
1608 * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
1611 #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
1614 extern int ___pskb_trim(struct sk_buff
*skb
, unsigned int len
);
1616 static inline void __skb_trim(struct sk_buff
*skb
, unsigned int len
)
1618 if (unlikely(skb_is_nonlinear(skb
))) {
1623 skb_set_tail_pointer(skb
, len
);
1626 extern void skb_trim(struct sk_buff
*skb
, unsigned int len
);
1628 static inline int __pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1631 return ___pskb_trim(skb
, len
);
1632 __skb_trim(skb
, len
);
1636 static inline int pskb_trim(struct sk_buff
*skb
, unsigned int len
)
1638 return (len
< skb
->len
) ? __pskb_trim(skb
, len
) : 0;
1642 * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
1643 * @skb: buffer to alter
1646 * This is identical to pskb_trim except that the caller knows that
1647 * the skb is not cloned so we should never get an error due to out-
1650 static inline void pskb_trim_unique(struct sk_buff
*skb
, unsigned int len
)
1652 int err
= pskb_trim(skb
, len
);
1657 * skb_orphan - orphan a buffer
1658 * @skb: buffer to orphan
1660 * If a buffer currently has an owner then we call the owner's
1661 * destructor function and make the @skb unowned. The buffer continues
1662 * to exist but is no longer charged to its former owner.
1664 static inline void skb_orphan(struct sk_buff
*skb
)
1666 if (skb
->destructor
)
1667 skb
->destructor(skb
);
1668 skb
->destructor
= NULL
;
1673 * __skb_queue_purge - empty a list
1674 * @list: list to empty
1676 * Delete all buffers on an &sk_buff list. Each buffer is removed from
1677 * the list and one reference dropped. This function does not take the
1678 * list lock and the caller must hold the relevant locks to use it.
1680 extern void skb_queue_purge(struct sk_buff_head
*list
);
1681 static inline void __skb_queue_purge(struct sk_buff_head
*list
)
1683 struct sk_buff
*skb
;
1684 while ((skb
= __skb_dequeue(list
)) != NULL
)
1688 extern void *netdev_alloc_frag(unsigned int fragsz
);
1690 extern struct sk_buff
*__netdev_alloc_skb(struct net_device
*dev
,
1691 unsigned int length
,
1695 * netdev_alloc_skb - allocate an skbuff for rx on a specific device
1696 * @dev: network device to receive on
1697 * @length: length to allocate
1699 * Allocate a new &sk_buff and assign it a usage count of one. The
1700 * buffer has unspecified headroom built in. Users should allocate
1701 * the headroom they think they need without accounting for the
1702 * built in space. The built in space is used for optimisations.
1704 * %NULL is returned if there is no free memory. Although this function
1705 * allocates memory it can be called from an interrupt.
1707 static inline struct sk_buff
*netdev_alloc_skb(struct net_device
*dev
,
1708 unsigned int length
)
1710 return __netdev_alloc_skb(dev
, length
, GFP_ATOMIC
);
1713 /* legacy helper around __netdev_alloc_skb() */
1714 static inline struct sk_buff
*__dev_alloc_skb(unsigned int length
,
1717 return __netdev_alloc_skb(NULL
, length
, gfp_mask
);
1720 /* legacy helper around netdev_alloc_skb() */
1721 static inline struct sk_buff
*dev_alloc_skb(unsigned int length
)
1723 return netdev_alloc_skb(NULL
, length
);
1727 static inline struct sk_buff
*__netdev_alloc_skb_ip_align(struct net_device
*dev
,
1728 unsigned int length
, gfp_t gfp
)
1730 struct sk_buff
*skb
= __netdev_alloc_skb(dev
, length
+ NET_IP_ALIGN
, gfp
);
1732 if (NET_IP_ALIGN
&& skb
)
1733 skb_reserve(skb
, NET_IP_ALIGN
);
1737 static inline struct sk_buff
*netdev_alloc_skb_ip_align(struct net_device
*dev
,
1738 unsigned int length
)
1740 return __netdev_alloc_skb_ip_align(dev
, length
, GFP_ATOMIC
);
1744 * skb_frag_page - retrieve the page refered to by a paged fragment
1745 * @frag: the paged fragment
1747 * Returns the &struct page associated with @frag.
1749 static inline struct page
*skb_frag_page(const skb_frag_t
*frag
)
1751 return frag
->page
.p
;
1755 * __skb_frag_ref - take an addition reference on a paged fragment.
1756 * @frag: the paged fragment
1758 * Takes an additional reference on the paged fragment @frag.
1760 static inline void __skb_frag_ref(skb_frag_t
*frag
)
1762 get_page(skb_frag_page(frag
));
1766 * skb_frag_ref - take an addition reference on a paged fragment of an skb.
1768 * @f: the fragment offset.
1770 * Takes an additional reference on the @f'th paged fragment of @skb.
1772 static inline void skb_frag_ref(struct sk_buff
*skb
, int f
)
1774 __skb_frag_ref(&skb_shinfo(skb
)->frags
[f
]);
1778 * __skb_frag_unref - release a reference on a paged fragment.
1779 * @frag: the paged fragment
1781 * Releases a reference on the paged fragment @frag.
1783 static inline void __skb_frag_unref(skb_frag_t
*frag
)
1785 put_page(skb_frag_page(frag
));
1789 * skb_frag_unref - release a reference on a paged fragment of an skb.
1791 * @f: the fragment offset
1793 * Releases a reference on the @f'th paged fragment of @skb.
1795 static inline void skb_frag_unref(struct sk_buff
*skb
, int f
)
1797 __skb_frag_unref(&skb_shinfo(skb
)->frags
[f
]);
1801 * skb_frag_address - gets the address of the data contained in a paged fragment
1802 * @frag: the paged fragment buffer
1804 * Returns the address of the data within @frag. The page must already
1807 static inline void *skb_frag_address(const skb_frag_t
*frag
)
1809 return page_address(skb_frag_page(frag
)) + frag
->page_offset
;
1813 * skb_frag_address_safe - gets the address of the data contained in a paged fragment
1814 * @frag: the paged fragment buffer
1816 * Returns the address of the data within @frag. Checks that the page
1817 * is mapped and returns %NULL otherwise.
1819 static inline void *skb_frag_address_safe(const skb_frag_t
*frag
)
1821 void *ptr
= page_address(skb_frag_page(frag
));
1825 return ptr
+ frag
->page_offset
;
1829 * __skb_frag_set_page - sets the page contained in a paged fragment
1830 * @frag: the paged fragment
1831 * @page: the page to set
1833 * Sets the fragment @frag to contain @page.
1835 static inline void __skb_frag_set_page(skb_frag_t
*frag
, struct page
*page
)
1837 frag
->page
.p
= page
;
1841 * skb_frag_set_page - sets the page contained in a paged fragment of an skb
1843 * @f: the fragment offset
1844 * @page: the page to set
1846 * Sets the @f'th fragment of @skb to contain @page.
1848 static inline void skb_frag_set_page(struct sk_buff
*skb
, int f
,
1851 __skb_frag_set_page(&skb_shinfo(skb
)->frags
[f
], page
);
1855 * skb_frag_dma_map - maps a paged fragment via the DMA API
1856 * @dev: the device to map the fragment to
1857 * @frag: the paged fragment to map
1858 * @offset: the offset within the fragment (starting at the
1859 * fragment's own offset)
1860 * @size: the number of bytes to map
1861 * @dir: the direction of the mapping (%PCI_DMA_*)
1863 * Maps the page associated with @frag to @device.
1865 static inline dma_addr_t
skb_frag_dma_map(struct device
*dev
,
1866 const skb_frag_t
*frag
,
1867 size_t offset
, size_t size
,
1868 enum dma_data_direction dir
)
1870 return dma_map_page(dev
, skb_frag_page(frag
),
1871 frag
->page_offset
+ offset
, size
, dir
);
1874 static inline struct sk_buff
*pskb_copy(struct sk_buff
*skb
,
1877 return __pskb_copy(skb
, skb_headroom(skb
), gfp_mask
);
1881 * skb_clone_writable - is the header of a clone writable
1882 * @skb: buffer to check
1883 * @len: length up to which to write
1885 * Returns true if modifying the header part of the cloned buffer
1886 * does not requires the data to be copied.
1888 static inline int skb_clone_writable(const struct sk_buff
*skb
, unsigned int len
)
1890 return !skb_header_cloned(skb
) &&
1891 skb_headroom(skb
) + len
<= skb
->hdr_len
;
1894 static inline int __skb_cow(struct sk_buff
*skb
, unsigned int headroom
,
1899 if (headroom
> skb_headroom(skb
))
1900 delta
= headroom
- skb_headroom(skb
);
1902 if (delta
|| cloned
)
1903 return pskb_expand_head(skb
, ALIGN(delta
, NET_SKB_PAD
), 0,
1909 * skb_cow - copy header of skb when it is required
1910 * @skb: buffer to cow
1911 * @headroom: needed headroom
1913 * If the skb passed lacks sufficient headroom or its data part
1914 * is shared, data is reallocated. If reallocation fails, an error
1915 * is returned and original skb is not changed.
1917 * The result is skb with writable area skb->head...skb->tail
1918 * and at least @headroom of space at head.
1920 static inline int skb_cow(struct sk_buff
*skb
, unsigned int headroom
)
1922 return __skb_cow(skb
, headroom
, skb_cloned(skb
));
1926 * skb_cow_head - skb_cow but only making the head writable
1927 * @skb: buffer to cow
1928 * @headroom: needed headroom
1930 * This function is identical to skb_cow except that we replace the
1931 * skb_cloned check by skb_header_cloned. It should be used when
1932 * you only need to push on some header and do not need to modify
1935 static inline int skb_cow_head(struct sk_buff
*skb
, unsigned int headroom
)
1937 return __skb_cow(skb
, headroom
, skb_header_cloned(skb
));
1941 * skb_padto - pad an skbuff up to a minimal size
1942 * @skb: buffer to pad
1943 * @len: minimal length
1945 * Pads up a buffer to ensure the trailing bytes exist and are
1946 * blanked. If the buffer already contains sufficient data it
1947 * is untouched. Otherwise it is extended. Returns zero on
1948 * success. The skb is freed on error.
1951 static inline int skb_padto(struct sk_buff
*skb
, unsigned int len
)
1953 unsigned int size
= skb
->len
;
1954 if (likely(size
>= len
))
1956 return skb_pad(skb
, len
- size
);
1959 static inline int skb_add_data(struct sk_buff
*skb
,
1960 char __user
*from
, int copy
)
1962 const int off
= skb
->len
;
1964 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1966 __wsum csum
= csum_and_copy_from_user(from
, skb_put(skb
, copy
),
1969 skb
->csum
= csum_block_add(skb
->csum
, csum
, off
);
1972 } else if (!copy_from_user(skb_put(skb
, copy
), from
, copy
))
1975 __skb_trim(skb
, off
);
1979 static inline bool skb_can_coalesce(struct sk_buff
*skb
, int i
,
1980 const struct page
*page
, int off
)
1983 const struct skb_frag_struct
*frag
= &skb_shinfo(skb
)->frags
[i
- 1];
1985 return page
== skb_frag_page(frag
) &&
1986 off
== frag
->page_offset
+ skb_frag_size(frag
);
1991 static inline int __skb_linearize(struct sk_buff
*skb
)
1993 return __pskb_pull_tail(skb
, skb
->data_len
) ? 0 : -ENOMEM
;
1997 * skb_linearize - convert paged skb to linear one
1998 * @skb: buffer to linarize
2000 * If there is no free memory -ENOMEM is returned, otherwise zero
2001 * is returned and the old skb data released.
2003 static inline int skb_linearize(struct sk_buff
*skb
)
2005 return skb_is_nonlinear(skb
) ? __skb_linearize(skb
) : 0;
2009 * skb_linearize_cow - make sure skb is linear and writable
2010 * @skb: buffer to process
2012 * If there is no free memory -ENOMEM is returned, otherwise zero
2013 * is returned and the old skb data released.
2015 static inline int skb_linearize_cow(struct sk_buff
*skb
)
2017 return skb_is_nonlinear(skb
) || skb_cloned(skb
) ?
2018 __skb_linearize(skb
) : 0;
2022 * skb_postpull_rcsum - update checksum for received skb after pull
2023 * @skb: buffer to update
2024 * @start: start of data before pull
2025 * @len: length of data pulled
2027 * After doing a pull on a received packet, you need to call this to
2028 * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
2029 * CHECKSUM_NONE so that it can be recomputed from scratch.
2032 static inline void skb_postpull_rcsum(struct sk_buff
*skb
,
2033 const void *start
, unsigned int len
)
2035 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2036 skb
->csum
= csum_sub(skb
->csum
, csum_partial(start
, len
, 0));
2039 unsigned char *skb_pull_rcsum(struct sk_buff
*skb
, unsigned int len
);
2042 * pskb_trim_rcsum - trim received skb and update checksum
2043 * @skb: buffer to trim
2046 * This is exactly the same as pskb_trim except that it ensures the
2047 * checksum of received packets are still valid after the operation.
2050 static inline int pskb_trim_rcsum(struct sk_buff
*skb
, unsigned int len
)
2052 if (likely(len
>= skb
->len
))
2054 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2055 skb
->ip_summed
= CHECKSUM_NONE
;
2056 return __pskb_trim(skb
, len
);
2059 #define skb_queue_walk(queue, skb) \
2060 for (skb = (queue)->next; \
2061 skb != (struct sk_buff *)(queue); \
2064 #define skb_queue_walk_safe(queue, skb, tmp) \
2065 for (skb = (queue)->next, tmp = skb->next; \
2066 skb != (struct sk_buff *)(queue); \
2067 skb = tmp, tmp = skb->next)
2069 #define skb_queue_walk_from(queue, skb) \
2070 for (; skb != (struct sk_buff *)(queue); \
2073 #define skb_queue_walk_from_safe(queue, skb, tmp) \
2074 for (tmp = skb->next; \
2075 skb != (struct sk_buff *)(queue); \
2076 skb = tmp, tmp = skb->next)
2078 #define skb_queue_reverse_walk(queue, skb) \
2079 for (skb = (queue)->prev; \
2080 skb != (struct sk_buff *)(queue); \
2083 #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
2084 for (skb = (queue)->prev, tmp = skb->prev; \
2085 skb != (struct sk_buff *)(queue); \
2086 skb = tmp, tmp = skb->prev)
2088 #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
2089 for (tmp = skb->prev; \
2090 skb != (struct sk_buff *)(queue); \
2091 skb = tmp, tmp = skb->prev)
2093 static inline bool skb_has_frag_list(const struct sk_buff
*skb
)
2095 return skb_shinfo(skb
)->frag_list
!= NULL
;
2098 static inline void skb_frag_list_init(struct sk_buff
*skb
)
2100 skb_shinfo(skb
)->frag_list
= NULL
;
2103 static inline void skb_frag_add_head(struct sk_buff
*skb
, struct sk_buff
*frag
)
2105 frag
->next
= skb_shinfo(skb
)->frag_list
;
2106 skb_shinfo(skb
)->frag_list
= frag
;
2109 #define skb_walk_frags(skb, iter) \
2110 for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
2112 extern struct sk_buff
*__skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2113 int *peeked
, int *off
, int *err
);
2114 extern struct sk_buff
*skb_recv_datagram(struct sock
*sk
, unsigned flags
,
2115 int noblock
, int *err
);
2116 extern unsigned int datagram_poll(struct file
*file
, struct socket
*sock
,
2117 struct poll_table_struct
*wait
);
2118 extern int skb_copy_datagram_iovec(const struct sk_buff
*from
,
2119 int offset
, struct iovec
*to
,
2121 extern int skb_copy_and_csum_datagram_iovec(struct sk_buff
*skb
,
2124 extern int skb_copy_datagram_from_iovec(struct sk_buff
*skb
,
2126 const struct iovec
*from
,
2129 extern int skb_copy_datagram_const_iovec(const struct sk_buff
*from
,
2131 const struct iovec
*to
,
2134 extern void skb_free_datagram(struct sock
*sk
, struct sk_buff
*skb
);
2135 extern void skb_free_datagram_locked(struct sock
*sk
,
2136 struct sk_buff
*skb
);
2137 extern int skb_kill_datagram(struct sock
*sk
, struct sk_buff
*skb
,
2138 unsigned int flags
);
2139 extern __wsum
skb_checksum(const struct sk_buff
*skb
, int offset
,
2140 int len
, __wsum csum
);
2141 extern int skb_copy_bits(const struct sk_buff
*skb
, int offset
,
2143 extern int skb_store_bits(struct sk_buff
*skb
, int offset
,
2144 const void *from
, int len
);
2145 extern __wsum
skb_copy_and_csum_bits(const struct sk_buff
*skb
,
2146 int offset
, u8
*to
, int len
,
2148 extern int skb_splice_bits(struct sk_buff
*skb
,
2149 unsigned int offset
,
2150 struct pipe_inode_info
*pipe
,
2152 unsigned int flags
);
2153 extern void skb_copy_and_csum_dev(const struct sk_buff
*skb
, u8
*to
);
2154 extern void skb_split(struct sk_buff
*skb
,
2155 struct sk_buff
*skb1
, const u32 len
);
2156 extern int skb_shift(struct sk_buff
*tgt
, struct sk_buff
*skb
,
2159 extern struct sk_buff
*skb_segment(struct sk_buff
*skb
,
2160 netdev_features_t features
);
2162 static inline void *skb_header_pointer(const struct sk_buff
*skb
, int offset
,
2163 int len
, void *buffer
)
2165 int hlen
= skb_headlen(skb
);
2167 if (hlen
- offset
>= len
)
2168 return skb
->data
+ offset
;
2170 if (skb_copy_bits(skb
, offset
, buffer
, len
) < 0)
2176 static inline void skb_copy_from_linear_data(const struct sk_buff
*skb
,
2178 const unsigned int len
)
2180 memcpy(to
, skb
->data
, len
);
2183 static inline void skb_copy_from_linear_data_offset(const struct sk_buff
*skb
,
2184 const int offset
, void *to
,
2185 const unsigned int len
)
2187 memcpy(to
, skb
->data
+ offset
, len
);
2190 static inline void skb_copy_to_linear_data(struct sk_buff
*skb
,
2192 const unsigned int len
)
2194 memcpy(skb
->data
, from
, len
);
2197 static inline void skb_copy_to_linear_data_offset(struct sk_buff
*skb
,
2200 const unsigned int len
)
2202 memcpy(skb
->data
+ offset
, from
, len
);
2205 extern void skb_init(void);
2207 static inline ktime_t
skb_get_ktime(const struct sk_buff
*skb
)
2213 * skb_get_timestamp - get timestamp from a skb
2214 * @skb: skb to get stamp from
2215 * @stamp: pointer to struct timeval to store stamp in
2217 * Timestamps are stored in the skb as offsets to a base timestamp.
2218 * This function converts the offset back to a struct timeval and stores
2221 static inline void skb_get_timestamp(const struct sk_buff
*skb
,
2222 struct timeval
*stamp
)
2224 *stamp
= ktime_to_timeval(skb
->tstamp
);
2227 static inline void skb_get_timestampns(const struct sk_buff
*skb
,
2228 struct timespec
*stamp
)
2230 *stamp
= ktime_to_timespec(skb
->tstamp
);
2233 static inline void __net_timestamp(struct sk_buff
*skb
)
2235 skb
->tstamp
= ktime_get_real();
2238 static inline ktime_t
net_timedelta(ktime_t t
)
2240 return ktime_sub(ktime_get_real(), t
);
2243 static inline ktime_t
net_invalid_timestamp(void)
2245 return ktime_set(0, 0);
2248 extern void skb_timestamping_init(void);
2250 #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
2252 extern void skb_clone_tx_timestamp(struct sk_buff
*skb
);
2253 extern bool skb_defer_rx_timestamp(struct sk_buff
*skb
);
2255 #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
2257 static inline void skb_clone_tx_timestamp(struct sk_buff
*skb
)
2261 static inline bool skb_defer_rx_timestamp(struct sk_buff
*skb
)
2266 #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
2269 * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
2271 * PHY drivers may accept clones of transmitted packets for
2272 * timestamping via their phy_driver.txtstamp method. These drivers
2273 * must call this function to return the skb back to the stack, with
2274 * or without a timestamp.
2276 * @skb: clone of the the original outgoing packet
2277 * @hwtstamps: hardware time stamps, may be NULL if not available
2280 void skb_complete_tx_timestamp(struct sk_buff
*skb
,
2281 struct skb_shared_hwtstamps
*hwtstamps
);
2284 * skb_tstamp_tx - queue clone of skb with send time stamps
2285 * @orig_skb: the original outgoing packet
2286 * @hwtstamps: hardware time stamps, may be NULL if not available
2288 * If the skb has a socket associated, then this function clones the
2289 * skb (thus sharing the actual data and optional structures), stores
2290 * the optional hardware time stamping information (if non NULL) or
2291 * generates a software time stamp (otherwise), then queues the clone
2292 * to the error queue of the socket. Errors are silently ignored.
2294 extern void skb_tstamp_tx(struct sk_buff
*orig_skb
,
2295 struct skb_shared_hwtstamps
*hwtstamps
);
2297 static inline void sw_tx_timestamp(struct sk_buff
*skb
)
2299 if (skb_shinfo(skb
)->tx_flags
& SKBTX_SW_TSTAMP
&&
2300 !(skb_shinfo(skb
)->tx_flags
& SKBTX_IN_PROGRESS
))
2301 skb_tstamp_tx(skb
, NULL
);
2305 * skb_tx_timestamp() - Driver hook for transmit timestamping
2307 * Ethernet MAC Drivers should call this function in their hard_xmit()
2308 * function immediately before giving the sk_buff to the MAC hardware.
2310 * @skb: A socket buffer.
2312 static inline void skb_tx_timestamp(struct sk_buff
*skb
)
2314 skb_clone_tx_timestamp(skb
);
2315 sw_tx_timestamp(skb
);
2319 * skb_complete_wifi_ack - deliver skb with wifi status
2321 * @skb: the original outgoing packet
2322 * @acked: ack status
2325 void skb_complete_wifi_ack(struct sk_buff
*skb
, bool acked
);
2327 extern __sum16
__skb_checksum_complete_head(struct sk_buff
*skb
, int len
);
2328 extern __sum16
__skb_checksum_complete(struct sk_buff
*skb
);
2330 static inline int skb_csum_unnecessary(const struct sk_buff
*skb
)
2332 return skb
->ip_summed
& CHECKSUM_UNNECESSARY
;
2336 * skb_checksum_complete - Calculate checksum of an entire packet
2337 * @skb: packet to process
2339 * This function calculates the checksum over the entire packet plus
2340 * the value of skb->csum. The latter can be used to supply the
2341 * checksum of a pseudo header as used by TCP/UDP. It returns the
2344 * For protocols that contain complete checksums such as ICMP/TCP/UDP,
2345 * this function can be used to verify that checksum on received
2346 * packets. In that case the function should return zero if the
2347 * checksum is correct. In particular, this function will return zero
2348 * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
2349 * hardware has already verified the correctness of the checksum.
2351 static inline __sum16
skb_checksum_complete(struct sk_buff
*skb
)
2353 return skb_csum_unnecessary(skb
) ?
2354 0 : __skb_checksum_complete(skb
);
2357 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2358 extern void nf_conntrack_destroy(struct nf_conntrack
*nfct
);
2359 static inline void nf_conntrack_put(struct nf_conntrack
*nfct
)
2361 if (nfct
&& atomic_dec_and_test(&nfct
->use
))
2362 nf_conntrack_destroy(nfct
);
2364 static inline void nf_conntrack_get(struct nf_conntrack
*nfct
)
2367 atomic_inc(&nfct
->use
);
2370 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2371 static inline void nf_conntrack_get_reasm(struct sk_buff
*skb
)
2374 atomic_inc(&skb
->users
);
2376 static inline void nf_conntrack_put_reasm(struct sk_buff
*skb
)
2382 #ifdef CONFIG_BRIDGE_NETFILTER
2383 static inline void nf_bridge_put(struct nf_bridge_info
*nf_bridge
)
2385 if (nf_bridge
&& atomic_dec_and_test(&nf_bridge
->use
))
2388 static inline void nf_bridge_get(struct nf_bridge_info
*nf_bridge
)
2391 atomic_inc(&nf_bridge
->use
);
2393 #endif /* CONFIG_BRIDGE_NETFILTER */
2394 static inline void nf_reset(struct sk_buff
*skb
)
2396 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2397 nf_conntrack_put(skb
->nfct
);
2400 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2401 nf_conntrack_put_reasm(skb
->nfct_reasm
);
2402 skb
->nfct_reasm
= NULL
;
2404 #ifdef CONFIG_BRIDGE_NETFILTER
2405 nf_bridge_put(skb
->nf_bridge
);
2406 skb
->nf_bridge
= NULL
;
2410 /* Note: This doesn't put any conntrack and bridge info in dst. */
2411 static inline void __nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2413 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2414 dst
->nfct
= src
->nfct
;
2415 nf_conntrack_get(src
->nfct
);
2416 dst
->nfctinfo
= src
->nfctinfo
;
2418 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2419 dst
->nfct_reasm
= src
->nfct_reasm
;
2420 nf_conntrack_get_reasm(src
->nfct_reasm
);
2422 #ifdef CONFIG_BRIDGE_NETFILTER
2423 dst
->nf_bridge
= src
->nf_bridge
;
2424 nf_bridge_get(src
->nf_bridge
);
2428 static inline void nf_copy(struct sk_buff
*dst
, const struct sk_buff
*src
)
2430 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
2431 nf_conntrack_put(dst
->nfct
);
2433 #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
2434 nf_conntrack_put_reasm(dst
->nfct_reasm
);
2436 #ifdef CONFIG_BRIDGE_NETFILTER
2437 nf_bridge_put(dst
->nf_bridge
);
2439 __nf_copy(dst
, src
);
2442 #ifdef CONFIG_NETWORK_SECMARK
2443 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2445 to
->secmark
= from
->secmark
;
2448 static inline void skb_init_secmark(struct sk_buff
*skb
)
2453 static inline void skb_copy_secmark(struct sk_buff
*to
, const struct sk_buff
*from
)
2456 static inline void skb_init_secmark(struct sk_buff
*skb
)
2460 static inline void skb_set_queue_mapping(struct sk_buff
*skb
, u16 queue_mapping
)
2462 skb
->queue_mapping
= queue_mapping
;
2465 static inline u16
skb_get_queue_mapping(const struct sk_buff
*skb
)
2467 return skb
->queue_mapping
;
2470 static inline void skb_copy_queue_mapping(struct sk_buff
*to
, const struct sk_buff
*from
)
2472 to
->queue_mapping
= from
->queue_mapping
;
2475 static inline void skb_record_rx_queue(struct sk_buff
*skb
, u16 rx_queue
)
2477 skb
->queue_mapping
= rx_queue
+ 1;
2480 static inline u16
skb_get_rx_queue(const struct sk_buff
*skb
)
2482 return skb
->queue_mapping
- 1;
2485 static inline bool skb_rx_queue_recorded(const struct sk_buff
*skb
)
2487 return skb
->queue_mapping
!= 0;
2490 extern u16
__skb_tx_hash(const struct net_device
*dev
,
2491 const struct sk_buff
*skb
,
2492 unsigned int num_tx_queues
);
2495 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2500 static inline struct sec_path
*skb_sec_path(struct sk_buff
*skb
)
2506 static inline bool skb_is_gso(const struct sk_buff
*skb
)
2508 return skb_shinfo(skb
)->gso_size
;
2511 static inline bool skb_is_gso_v6(const struct sk_buff
*skb
)
2513 return skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
;
2516 extern void __skb_warn_lro_forwarding(const struct sk_buff
*skb
);
2518 static inline bool skb_warn_if_lro(const struct sk_buff
*skb
)
2520 /* LRO sets gso_size but not gso_type, whereas if GSO is really
2521 * wanted then gso_type will be set. */
2522 const struct skb_shared_info
*shinfo
= skb_shinfo(skb
);
2524 if (skb_is_nonlinear(skb
) && shinfo
->gso_size
!= 0 &&
2525 unlikely(shinfo
->gso_type
== 0)) {
2526 __skb_warn_lro_forwarding(skb
);
2532 static inline void skb_forward_csum(struct sk_buff
*skb
)
2534 /* Unfortunately we don't support this one. Any brave souls? */
2535 if (skb
->ip_summed
== CHECKSUM_COMPLETE
)
2536 skb
->ip_summed
= CHECKSUM_NONE
;
2540 * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
2541 * @skb: skb to check
2543 * fresh skbs have their ip_summed set to CHECKSUM_NONE.
2544 * Instead of forcing ip_summed to CHECKSUM_NONE, we can
2545 * use this helper, to document places where we make this assertion.
2547 static inline void skb_checksum_none_assert(const struct sk_buff
*skb
)
2550 BUG_ON(skb
->ip_summed
!= CHECKSUM_NONE
);
2554 bool skb_partial_csum_set(struct sk_buff
*skb
, u16 start
, u16 off
);
2556 static inline bool skb_is_recycleable(const struct sk_buff
*skb
, int skb_size
)
2558 if (irqs_disabled())
2561 if (skb_shinfo(skb
)->tx_flags
& SKBTX_DEV_ZEROCOPY
)
2564 if (skb_is_nonlinear(skb
) || skb
->fclone
!= SKB_FCLONE_UNAVAILABLE
)
2567 skb_size
= SKB_DATA_ALIGN(skb_size
+ NET_SKB_PAD
);
2568 if (skb_end_offset(skb
) < skb_size
)
2571 if (skb_shared(skb
) || skb_cloned(skb
))
2578 * skb_head_is_locked - Determine if the skb->head is locked down
2579 * @skb: skb to check
2581 * The head on skbs build around a head frag can be removed if they are
2582 * not cloned. This function returns true if the skb head is locked down
2583 * due to either being allocated via kmalloc, or by being a clone with
2584 * multiple references to the head.
2586 static inline bool skb_head_is_locked(const struct sk_buff
*skb
)
2588 return !skb
->head_frag
|| skb_cloned(skb
);
2590 #endif /* __KERNEL__ */
2591 #endif /* _LINUX_SKBUFF_H */