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1 | /* | |
2 | * Definitions for the 'struct sk_buff' memory handlers. | |
3 | * | |
4 | * Authors: | |
5 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
6 | * Florian La Roche, <rzsfl@rz.uni-sb.de> | |
7 | * | |
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. | |
12 | */ | |
13 | ||
14 | #ifndef _LINUX_SKBUFF_H | |
15 | #define _LINUX_SKBUFF_H | |
16 | ||
17 | #include <linux/kernel.h> | |
18 | #include <linux/compiler.h> | |
19 | #include <linux/time.h> | |
20 | #include <linux/cache.h> | |
21 | ||
22 | #include <asm/atomic.h> | |
23 | #include <asm/types.h> | |
24 | #include <linux/spinlock.h> | |
25 | #include <linux/net.h> | |
26 | #include <linux/textsearch.h> | |
27 | #include <net/checksum.h> | |
28 | #include <linux/rcupdate.h> | |
29 | #include <linux/dmaengine.h> | |
30 | #include <linux/hrtimer.h> | |
31 | ||
32 | #define HAVE_ALLOC_SKB /* For the drivers to know */ | |
33 | #define HAVE_ALIGNABLE_SKB /* Ditto 8) */ | |
34 | ||
35 | /* Don't change this without changing skb_csum_unnecessary! */ | |
36 | #define CHECKSUM_NONE 0 | |
37 | #define CHECKSUM_UNNECESSARY 1 | |
38 | #define CHECKSUM_COMPLETE 2 | |
39 | #define CHECKSUM_PARTIAL 3 | |
40 | ||
41 | #define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \ | |
42 | ~(SMP_CACHE_BYTES - 1)) | |
43 | #define SKB_WITH_OVERHEAD(X) \ | |
44 | (((X) - sizeof(struct skb_shared_info)) & \ | |
45 | ~(SMP_CACHE_BYTES - 1)) | |
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)) | |
50 | ||
51 | /* A. Checksumming of received packets by device. | |
52 | * | |
53 | * NONE: device failed to checksum this packet. | |
54 | * skb->csum is undefined. | |
55 | * | |
56 | * UNNECESSARY: device parsed packet and wouldbe verified checksum. | |
57 | * skb->csum is undefined. | |
58 | * It is bad option, but, unfortunately, many of vendors do this. | |
59 | * Apparently with secret goal to sell you new device, when you | |
60 | * will add new protocol to your host. F.e. IPv6. 8) | |
61 | * | |
62 | * COMPLETE: the most generic way. Device supplied checksum of _all_ | |
63 | * the packet as seen by netif_rx in skb->csum. | |
64 | * NOTE: Even if device supports only some protocols, but | |
65 | * is able to produce some skb->csum, it MUST use COMPLETE, | |
66 | * not UNNECESSARY. | |
67 | * | |
68 | * B. Checksumming on output. | |
69 | * | |
70 | * NONE: skb is checksummed by protocol or csum is not required. | |
71 | * | |
72 | * PARTIAL: device is required to csum packet as seen by hard_start_xmit | |
73 | * from skb->transport_header to the end and to record the checksum | |
74 | * at skb->transport_header + skb->csum. | |
75 | * | |
76 | * Device must show its capabilities in dev->features, set | |
77 | * at device setup time. | |
78 | * NETIF_F_HW_CSUM - it is clever device, it is able to checksum | |
79 | * everything. | |
80 | * NETIF_F_NO_CSUM - loopback or reliable single hop media. | |
81 | * NETIF_F_IP_CSUM - device is dumb. It is able to csum only | |
82 | * TCP/UDP over IPv4. Sigh. Vendors like this | |
83 | * way by an unknown reason. Though, see comment above | |
84 | * about CHECKSUM_UNNECESSARY. 8) | |
85 | * | |
86 | * Any questions? No questions, good. --ANK | |
87 | */ | |
88 | ||
89 | struct net_device; | |
90 | struct scatterlist; | |
91 | ||
92 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
93 | struct nf_conntrack { | |
94 | atomic_t use; | |
95 | }; | |
96 | #endif | |
97 | ||
98 | #ifdef CONFIG_BRIDGE_NETFILTER | |
99 | struct nf_bridge_info { | |
100 | atomic_t use; | |
101 | struct net_device *physindev; | |
102 | struct net_device *physoutdev; | |
103 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) | |
104 | struct net_device *netoutdev; | |
105 | #endif | |
106 | unsigned int mask; | |
107 | unsigned long data[32 / sizeof(unsigned long)]; | |
108 | }; | |
109 | #endif | |
110 | ||
111 | struct sk_buff_head { | |
112 | /* These two members must be first. */ | |
113 | struct sk_buff *next; | |
114 | struct sk_buff *prev; | |
115 | ||
116 | __u32 qlen; | |
117 | spinlock_t lock; | |
118 | }; | |
119 | ||
120 | struct sk_buff; | |
121 | ||
122 | /* To allow 64K frame to be packed as single skb without frag_list */ | |
123 | #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2) | |
124 | ||
125 | typedef struct skb_frag_struct skb_frag_t; | |
126 | ||
127 | struct skb_frag_struct { | |
128 | struct page *page; | |
129 | __u16 page_offset; | |
130 | __u16 size; | |
131 | }; | |
132 | ||
133 | /* This data is invariant across clones and lives at | |
134 | * the end of the header data, ie. at skb->end. | |
135 | */ | |
136 | struct skb_shared_info { | |
137 | atomic_t dataref; | |
138 | unsigned short nr_frags; | |
139 | unsigned short gso_size; | |
140 | /* Warning: this field is not always filled in (UFO)! */ | |
141 | unsigned short gso_segs; | |
142 | unsigned short gso_type; | |
143 | __be32 ip6_frag_id; | |
144 | struct sk_buff *frag_list; | |
145 | skb_frag_t frags[MAX_SKB_FRAGS]; | |
146 | }; | |
147 | ||
148 | /* We divide dataref into two halves. The higher 16 bits hold references | |
149 | * to the payload part of skb->data. The lower 16 bits hold references to | |
150 | * the entire skb->data. A clone of a headerless skb holds the length of | |
151 | * the header in skb->hdr_len. | |
152 | * | |
153 | * All users must obey the rule that the skb->data reference count must be | |
154 | * greater than or equal to the payload reference count. | |
155 | * | |
156 | * Holding a reference to the payload part means that the user does not | |
157 | * care about modifications to the header part of skb->data. | |
158 | */ | |
159 | #define SKB_DATAREF_SHIFT 16 | |
160 | #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) | |
161 | ||
162 | ||
163 | enum { | |
164 | SKB_FCLONE_UNAVAILABLE, | |
165 | SKB_FCLONE_ORIG, | |
166 | SKB_FCLONE_CLONE, | |
167 | }; | |
168 | ||
169 | enum { | |
170 | SKB_GSO_TCPV4 = 1 << 0, | |
171 | SKB_GSO_UDP = 1 << 1, | |
172 | ||
173 | /* This indicates the skb is from an untrusted source. */ | |
174 | SKB_GSO_DODGY = 1 << 2, | |
175 | ||
176 | /* This indicates the tcp segment has CWR set. */ | |
177 | SKB_GSO_TCP_ECN = 1 << 3, | |
178 | ||
179 | SKB_GSO_TCPV6 = 1 << 4, | |
180 | }; | |
181 | ||
182 | #if BITS_PER_LONG > 32 | |
183 | #define NET_SKBUFF_DATA_USES_OFFSET 1 | |
184 | #endif | |
185 | ||
186 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
187 | typedef unsigned int sk_buff_data_t; | |
188 | #else | |
189 | typedef unsigned char *sk_buff_data_t; | |
190 | #endif | |
191 | ||
192 | /** | |
193 | * struct sk_buff - socket buffer | |
194 | * @next: Next buffer in list | |
195 | * @prev: Previous buffer in list | |
196 | * @sk: Socket we are owned by | |
197 | * @tstamp: Time we arrived | |
198 | * @dev: Device we arrived on/are leaving by | |
199 | * @iif: ifindex of device we arrived on | |
200 | * @transport_header: Transport layer header | |
201 | * @network_header: Network layer header | |
202 | * @mac_header: Link layer header | |
203 | * @dst: destination entry | |
204 | * @sp: the security path, used for xfrm | |
205 | * @cb: Control buffer. Free for use by every layer. Put private vars here | |
206 | * @len: Length of actual data | |
207 | * @data_len: Data length | |
208 | * @mac_len: Length of link layer header | |
209 | * @hdr_len: writable header length of cloned skb | |
210 | * @csum: Checksum (must include start/offset pair) | |
211 | * @csum_start: Offset from skb->head where checksumming should start | |
212 | * @csum_offset: Offset from csum_start where checksum should be stored | |
213 | * @local_df: allow local fragmentation | |
214 | * @cloned: Head may be cloned (check refcnt to be sure) | |
215 | * @nohdr: Payload reference only, must not modify header | |
216 | * @pkt_type: Packet class | |
217 | * @fclone: skbuff clone status | |
218 | * @ip_summed: Driver fed us an IP checksum | |
219 | * @priority: Packet queueing priority | |
220 | * @users: User count - see {datagram,tcp}.c | |
221 | * @protocol: Packet protocol from driver | |
222 | * @truesize: Buffer size | |
223 | * @head: Head of buffer | |
224 | * @data: Data head pointer | |
225 | * @tail: Tail pointer | |
226 | * @end: End pointer | |
227 | * @destructor: Destruct function | |
228 | * @mark: Generic packet mark | |
229 | * @nfct: Associated connection, if any | |
230 | * @ipvs_property: skbuff is owned by ipvs | |
231 | * @nfctinfo: Relationship of this skb to the connection | |
232 | * @nfct_reasm: netfilter conntrack re-assembly pointer | |
233 | * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c | |
234 | * @tc_index: Traffic control index | |
235 | * @tc_verd: traffic control verdict | |
236 | * @dma_cookie: a cookie to one of several possible DMA operations | |
237 | * done by skb DMA functions | |
238 | * @secmark: security marking | |
239 | */ | |
240 | ||
241 | struct sk_buff { | |
242 | /* These two members must be first. */ | |
243 | struct sk_buff *next; | |
244 | struct sk_buff *prev; | |
245 | ||
246 | struct sock *sk; | |
247 | ktime_t tstamp; | |
248 | struct net_device *dev; | |
249 | int iif; | |
250 | /* 4 byte hole on 64 bit*/ | |
251 | ||
252 | struct dst_entry *dst; | |
253 | struct sec_path *sp; | |
254 | ||
255 | /* | |
256 | * This is the control buffer. It is free to use for every | |
257 | * layer. Please put your private variables there. If you | |
258 | * want to keep them across layers you have to do a skb_clone() | |
259 | * first. This is owned by whoever has the skb queued ATM. | |
260 | */ | |
261 | char cb[48]; | |
262 | ||
263 | unsigned int len, | |
264 | data_len; | |
265 | __u16 mac_len, | |
266 | hdr_len; | |
267 | union { | |
268 | __wsum csum; | |
269 | struct { | |
270 | __u16 csum_start; | |
271 | __u16 csum_offset; | |
272 | }; | |
273 | }; | |
274 | __u32 priority; | |
275 | __u8 local_df:1, | |
276 | cloned:1, | |
277 | ip_summed:2, | |
278 | nohdr:1, | |
279 | nfctinfo:3; | |
280 | __u8 pkt_type:3, | |
281 | fclone:2, | |
282 | ipvs_property:1; | |
283 | __be16 protocol; | |
284 | ||
285 | void (*destructor)(struct sk_buff *skb); | |
286 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
287 | struct nf_conntrack *nfct; | |
288 | struct sk_buff *nfct_reasm; | |
289 | #endif | |
290 | #ifdef CONFIG_BRIDGE_NETFILTER | |
291 | struct nf_bridge_info *nf_bridge; | |
292 | #endif | |
293 | #ifdef CONFIG_NET_SCHED | |
294 | __u16 tc_index; /* traffic control index */ | |
295 | #ifdef CONFIG_NET_CLS_ACT | |
296 | __u16 tc_verd; /* traffic control verdict */ | |
297 | #endif | |
298 | #endif | |
299 | #ifdef CONFIG_NET_DMA | |
300 | dma_cookie_t dma_cookie; | |
301 | #endif | |
302 | #ifdef CONFIG_NETWORK_SECMARK | |
303 | __u32 secmark; | |
304 | #endif | |
305 | ||
306 | __u32 mark; | |
307 | ||
308 | sk_buff_data_t transport_header; | |
309 | sk_buff_data_t network_header; | |
310 | sk_buff_data_t mac_header; | |
311 | /* These elements must be at the end, see alloc_skb() for details. */ | |
312 | sk_buff_data_t tail; | |
313 | sk_buff_data_t end; | |
314 | unsigned char *head, | |
315 | *data; | |
316 | unsigned int truesize; | |
317 | atomic_t users; | |
318 | }; | |
319 | ||
320 | #ifdef __KERNEL__ | |
321 | /* | |
322 | * Handling routines are only of interest to the kernel | |
323 | */ | |
324 | #include <linux/slab.h> | |
325 | ||
326 | #include <asm/system.h> | |
327 | ||
328 | extern void kfree_skb(struct sk_buff *skb); | |
329 | extern void __kfree_skb(struct sk_buff *skb); | |
330 | extern struct sk_buff *__alloc_skb(unsigned int size, | |
331 | gfp_t priority, int fclone, int node); | |
332 | static inline struct sk_buff *alloc_skb(unsigned int size, | |
333 | gfp_t priority) | |
334 | { | |
335 | return __alloc_skb(size, priority, 0, -1); | |
336 | } | |
337 | ||
338 | static inline struct sk_buff *alloc_skb_fclone(unsigned int size, | |
339 | gfp_t priority) | |
340 | { | |
341 | return __alloc_skb(size, priority, 1, -1); | |
342 | } | |
343 | ||
344 | extern void kfree_skbmem(struct sk_buff *skb); | |
345 | extern struct sk_buff *skb_clone(struct sk_buff *skb, | |
346 | gfp_t priority); | |
347 | extern struct sk_buff *skb_copy(const struct sk_buff *skb, | |
348 | gfp_t priority); | |
349 | extern struct sk_buff *pskb_copy(struct sk_buff *skb, | |
350 | gfp_t gfp_mask); | |
351 | extern int pskb_expand_head(struct sk_buff *skb, | |
352 | int nhead, int ntail, | |
353 | gfp_t gfp_mask); | |
354 | extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, | |
355 | unsigned int headroom); | |
356 | extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb, | |
357 | int newheadroom, int newtailroom, | |
358 | gfp_t priority); | |
359 | extern int skb_to_sgvec(struct sk_buff *skb, | |
360 | struct scatterlist *sg, int offset, | |
361 | int len); | |
362 | extern int skb_cow_data(struct sk_buff *skb, int tailbits, | |
363 | struct sk_buff **trailer); | |
364 | extern int skb_pad(struct sk_buff *skb, int pad); | |
365 | #define dev_kfree_skb(a) kfree_skb(a) | |
366 | extern void skb_over_panic(struct sk_buff *skb, int len, | |
367 | void *here); | |
368 | extern void skb_under_panic(struct sk_buff *skb, int len, | |
369 | void *here); | |
370 | extern void skb_truesize_bug(struct sk_buff *skb); | |
371 | ||
372 | static inline void skb_truesize_check(struct sk_buff *skb) | |
373 | { | |
374 | if (unlikely((int)skb->truesize < sizeof(struct sk_buff) + skb->len)) | |
375 | skb_truesize_bug(skb); | |
376 | } | |
377 | ||
378 | extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, | |
379 | int getfrag(void *from, char *to, int offset, | |
380 | int len,int odd, struct sk_buff *skb), | |
381 | void *from, int length); | |
382 | ||
383 | struct skb_seq_state | |
384 | { | |
385 | __u32 lower_offset; | |
386 | __u32 upper_offset; | |
387 | __u32 frag_idx; | |
388 | __u32 stepped_offset; | |
389 | struct sk_buff *root_skb; | |
390 | struct sk_buff *cur_skb; | |
391 | __u8 *frag_data; | |
392 | }; | |
393 | ||
394 | extern void skb_prepare_seq_read(struct sk_buff *skb, | |
395 | unsigned int from, unsigned int to, | |
396 | struct skb_seq_state *st); | |
397 | extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data, | |
398 | struct skb_seq_state *st); | |
399 | extern void skb_abort_seq_read(struct skb_seq_state *st); | |
400 | ||
401 | extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, | |
402 | unsigned int to, struct ts_config *config, | |
403 | struct ts_state *state); | |
404 | ||
405 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
406 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
407 | { | |
408 | return skb->head + skb->end; | |
409 | } | |
410 | #else | |
411 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
412 | { | |
413 | return skb->end; | |
414 | } | |
415 | #endif | |
416 | ||
417 | /* Internal */ | |
418 | #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) | |
419 | ||
420 | /** | |
421 | * skb_queue_empty - check if a queue is empty | |
422 | * @list: queue head | |
423 | * | |
424 | * Returns true if the queue is empty, false otherwise. | |
425 | */ | |
426 | static inline int skb_queue_empty(const struct sk_buff_head *list) | |
427 | { | |
428 | return list->next == (struct sk_buff *)list; | |
429 | } | |
430 | ||
431 | /** | |
432 | * skb_get - reference buffer | |
433 | * @skb: buffer to reference | |
434 | * | |
435 | * Makes another reference to a socket buffer and returns a pointer | |
436 | * to the buffer. | |
437 | */ | |
438 | static inline struct sk_buff *skb_get(struct sk_buff *skb) | |
439 | { | |
440 | atomic_inc(&skb->users); | |
441 | return skb; | |
442 | } | |
443 | ||
444 | /* | |
445 | * If users == 1, we are the only owner and are can avoid redundant | |
446 | * atomic change. | |
447 | */ | |
448 | ||
449 | /** | |
450 | * skb_cloned - is the buffer a clone | |
451 | * @skb: buffer to check | |
452 | * | |
453 | * Returns true if the buffer was generated with skb_clone() and is | |
454 | * one of multiple shared copies of the buffer. Cloned buffers are | |
455 | * shared data so must not be written to under normal circumstances. | |
456 | */ | |
457 | static inline int skb_cloned(const struct sk_buff *skb) | |
458 | { | |
459 | return skb->cloned && | |
460 | (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; | |
461 | } | |
462 | ||
463 | /** | |
464 | * skb_header_cloned - is the header a clone | |
465 | * @skb: buffer to check | |
466 | * | |
467 | * Returns true if modifying the header part of the buffer requires | |
468 | * the data to be copied. | |
469 | */ | |
470 | static inline int skb_header_cloned(const struct sk_buff *skb) | |
471 | { | |
472 | int dataref; | |
473 | ||
474 | if (!skb->cloned) | |
475 | return 0; | |
476 | ||
477 | dataref = atomic_read(&skb_shinfo(skb)->dataref); | |
478 | dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); | |
479 | return dataref != 1; | |
480 | } | |
481 | ||
482 | /** | |
483 | * skb_header_release - release reference to header | |
484 | * @skb: buffer to operate on | |
485 | * | |
486 | * Drop a reference to the header part of the buffer. This is done | |
487 | * by acquiring a payload reference. You must not read from the header | |
488 | * part of skb->data after this. | |
489 | */ | |
490 | static inline void skb_header_release(struct sk_buff *skb) | |
491 | { | |
492 | BUG_ON(skb->nohdr); | |
493 | skb->nohdr = 1; | |
494 | atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); | |
495 | } | |
496 | ||
497 | /** | |
498 | * skb_shared - is the buffer shared | |
499 | * @skb: buffer to check | |
500 | * | |
501 | * Returns true if more than one person has a reference to this | |
502 | * buffer. | |
503 | */ | |
504 | static inline int skb_shared(const struct sk_buff *skb) | |
505 | { | |
506 | return atomic_read(&skb->users) != 1; | |
507 | } | |
508 | ||
509 | /** | |
510 | * skb_share_check - check if buffer is shared and if so clone it | |
511 | * @skb: buffer to check | |
512 | * @pri: priority for memory allocation | |
513 | * | |
514 | * If the buffer is shared the buffer is cloned and the old copy | |
515 | * drops a reference. A new clone with a single reference is returned. | |
516 | * If the buffer is not shared the original buffer is returned. When | |
517 | * being called from interrupt status or with spinlocks held pri must | |
518 | * be GFP_ATOMIC. | |
519 | * | |
520 | * NULL is returned on a memory allocation failure. | |
521 | */ | |
522 | static inline struct sk_buff *skb_share_check(struct sk_buff *skb, | |
523 | gfp_t pri) | |
524 | { | |
525 | might_sleep_if(pri & __GFP_WAIT); | |
526 | if (skb_shared(skb)) { | |
527 | struct sk_buff *nskb = skb_clone(skb, pri); | |
528 | kfree_skb(skb); | |
529 | skb = nskb; | |
530 | } | |
531 | return skb; | |
532 | } | |
533 | ||
534 | /* | |
535 | * Copy shared buffers into a new sk_buff. We effectively do COW on | |
536 | * packets to handle cases where we have a local reader and forward | |
537 | * and a couple of other messy ones. The normal one is tcpdumping | |
538 | * a packet thats being forwarded. | |
539 | */ | |
540 | ||
541 | /** | |
542 | * skb_unshare - make a copy of a shared buffer | |
543 | * @skb: buffer to check | |
544 | * @pri: priority for memory allocation | |
545 | * | |
546 | * If the socket buffer is a clone then this function creates a new | |
547 | * copy of the data, drops a reference count on the old copy and returns | |
548 | * the new copy with the reference count at 1. If the buffer is not a clone | |
549 | * the original buffer is returned. When called with a spinlock held or | |
550 | * from interrupt state @pri must be %GFP_ATOMIC | |
551 | * | |
552 | * %NULL is returned on a memory allocation failure. | |
553 | */ | |
554 | static inline struct sk_buff *skb_unshare(struct sk_buff *skb, | |
555 | gfp_t pri) | |
556 | { | |
557 | might_sleep_if(pri & __GFP_WAIT); | |
558 | if (skb_cloned(skb)) { | |
559 | struct sk_buff *nskb = skb_copy(skb, pri); | |
560 | kfree_skb(skb); /* Free our shared copy */ | |
561 | skb = nskb; | |
562 | } | |
563 | return skb; | |
564 | } | |
565 | ||
566 | /** | |
567 | * skb_peek | |
568 | * @list_: list to peek at | |
569 | * | |
570 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
571 | * be careful with this one. A peek leaves the buffer on the | |
572 | * list and someone else may run off with it. You must hold | |
573 | * the appropriate locks or have a private queue to do this. | |
574 | * | |
575 | * Returns %NULL for an empty list or a pointer to the head element. | |
576 | * The reference count is not incremented and the reference is therefore | |
577 | * volatile. Use with caution. | |
578 | */ | |
579 | static inline struct sk_buff *skb_peek(struct sk_buff_head *list_) | |
580 | { | |
581 | struct sk_buff *list = ((struct sk_buff *)list_)->next; | |
582 | if (list == (struct sk_buff *)list_) | |
583 | list = NULL; | |
584 | return list; | |
585 | } | |
586 | ||
587 | /** | |
588 | * skb_peek_tail | |
589 | * @list_: list to peek at | |
590 | * | |
591 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
592 | * be careful with this one. A peek leaves the buffer on the | |
593 | * list and someone else may run off with it. You must hold | |
594 | * the appropriate locks or have a private queue to do this. | |
595 | * | |
596 | * Returns %NULL for an empty list or a pointer to the tail element. | |
597 | * The reference count is not incremented and the reference is therefore | |
598 | * volatile. Use with caution. | |
599 | */ | |
600 | static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_) | |
601 | { | |
602 | struct sk_buff *list = ((struct sk_buff *)list_)->prev; | |
603 | if (list == (struct sk_buff *)list_) | |
604 | list = NULL; | |
605 | return list; | |
606 | } | |
607 | ||
608 | /** | |
609 | * skb_queue_len - get queue length | |
610 | * @list_: list to measure | |
611 | * | |
612 | * Return the length of an &sk_buff queue. | |
613 | */ | |
614 | static inline __u32 skb_queue_len(const struct sk_buff_head *list_) | |
615 | { | |
616 | return list_->qlen; | |
617 | } | |
618 | ||
619 | /* | |
620 | * This function creates a split out lock class for each invocation; | |
621 | * this is needed for now since a whole lot of users of the skb-queue | |
622 | * infrastructure in drivers have different locking usage (in hardirq) | |
623 | * than the networking core (in softirq only). In the long run either the | |
624 | * network layer or drivers should need annotation to consolidate the | |
625 | * main types of usage into 3 classes. | |
626 | */ | |
627 | static inline void skb_queue_head_init(struct sk_buff_head *list) | |
628 | { | |
629 | spin_lock_init(&list->lock); | |
630 | list->prev = list->next = (struct sk_buff *)list; | |
631 | list->qlen = 0; | |
632 | } | |
633 | ||
634 | static inline void skb_queue_head_init_class(struct sk_buff_head *list, | |
635 | struct lock_class_key *class) | |
636 | { | |
637 | skb_queue_head_init(list); | |
638 | lockdep_set_class(&list->lock, class); | |
639 | } | |
640 | ||
641 | /* | |
642 | * Insert an sk_buff at the start of a list. | |
643 | * | |
644 | * The "__skb_xxxx()" functions are the non-atomic ones that | |
645 | * can only be called with interrupts disabled. | |
646 | */ | |
647 | ||
648 | /** | |
649 | * __skb_queue_after - queue a buffer at the list head | |
650 | * @list: list to use | |
651 | * @prev: place after this buffer | |
652 | * @newsk: buffer to queue | |
653 | * | |
654 | * Queue a buffer int the middle of a list. This function takes no locks | |
655 | * and you must therefore hold required locks before calling it. | |
656 | * | |
657 | * A buffer cannot be placed on two lists at the same time. | |
658 | */ | |
659 | static inline void __skb_queue_after(struct sk_buff_head *list, | |
660 | struct sk_buff *prev, | |
661 | struct sk_buff *newsk) | |
662 | { | |
663 | struct sk_buff *next; | |
664 | list->qlen++; | |
665 | ||
666 | next = prev->next; | |
667 | newsk->next = next; | |
668 | newsk->prev = prev; | |
669 | next->prev = prev->next = newsk; | |
670 | } | |
671 | ||
672 | /** | |
673 | * __skb_queue_head - queue a buffer at the list head | |
674 | * @list: list to use | |
675 | * @newsk: buffer to queue | |
676 | * | |
677 | * Queue a buffer at the start of a list. This function takes no locks | |
678 | * and you must therefore hold required locks before calling it. | |
679 | * | |
680 | * A buffer cannot be placed on two lists at the same time. | |
681 | */ | |
682 | extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); | |
683 | static inline void __skb_queue_head(struct sk_buff_head *list, | |
684 | struct sk_buff *newsk) | |
685 | { | |
686 | __skb_queue_after(list, (struct sk_buff *)list, newsk); | |
687 | } | |
688 | ||
689 | /** | |
690 | * __skb_queue_tail - queue a buffer at the list tail | |
691 | * @list: list to use | |
692 | * @newsk: buffer to queue | |
693 | * | |
694 | * Queue a buffer at the end of a list. This function takes no locks | |
695 | * and you must therefore hold required locks before calling it. | |
696 | * | |
697 | * A buffer cannot be placed on two lists at the same time. | |
698 | */ | |
699 | extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); | |
700 | static inline void __skb_queue_tail(struct sk_buff_head *list, | |
701 | struct sk_buff *newsk) | |
702 | { | |
703 | struct sk_buff *prev, *next; | |
704 | ||
705 | list->qlen++; | |
706 | next = (struct sk_buff *)list; | |
707 | prev = next->prev; | |
708 | newsk->next = next; | |
709 | newsk->prev = prev; | |
710 | next->prev = prev->next = newsk; | |
711 | } | |
712 | ||
713 | ||
714 | /** | |
715 | * __skb_dequeue - remove from the head of the queue | |
716 | * @list: list to dequeue from | |
717 | * | |
718 | * Remove the head of the list. This function does not take any locks | |
719 | * so must be used with appropriate locks held only. The head item is | |
720 | * returned or %NULL if the list is empty. | |
721 | */ | |
722 | extern struct sk_buff *skb_dequeue(struct sk_buff_head *list); | |
723 | static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) | |
724 | { | |
725 | struct sk_buff *next, *prev, *result; | |
726 | ||
727 | prev = (struct sk_buff *) list; | |
728 | next = prev->next; | |
729 | result = NULL; | |
730 | if (next != prev) { | |
731 | result = next; | |
732 | next = next->next; | |
733 | list->qlen--; | |
734 | next->prev = prev; | |
735 | prev->next = next; | |
736 | result->next = result->prev = NULL; | |
737 | } | |
738 | return result; | |
739 | } | |
740 | ||
741 | ||
742 | /* | |
743 | * Insert a packet on a list. | |
744 | */ | |
745 | extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); | |
746 | static inline void __skb_insert(struct sk_buff *newsk, | |
747 | struct sk_buff *prev, struct sk_buff *next, | |
748 | struct sk_buff_head *list) | |
749 | { | |
750 | newsk->next = next; | |
751 | newsk->prev = prev; | |
752 | next->prev = prev->next = newsk; | |
753 | list->qlen++; | |
754 | } | |
755 | ||
756 | /* | |
757 | * Place a packet after a given packet in a list. | |
758 | */ | |
759 | extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); | |
760 | static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list) | |
761 | { | |
762 | __skb_insert(newsk, old, old->next, list); | |
763 | } | |
764 | ||
765 | /* | |
766 | * remove sk_buff from list. _Must_ be called atomically, and with | |
767 | * the list known.. | |
768 | */ | |
769 | extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); | |
770 | static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) | |
771 | { | |
772 | struct sk_buff *next, *prev; | |
773 | ||
774 | list->qlen--; | |
775 | next = skb->next; | |
776 | prev = skb->prev; | |
777 | skb->next = skb->prev = NULL; | |
778 | next->prev = prev; | |
779 | prev->next = next; | |
780 | } | |
781 | ||
782 | ||
783 | /* XXX: more streamlined implementation */ | |
784 | ||
785 | /** | |
786 | * __skb_dequeue_tail - remove from the tail of the queue | |
787 | * @list: list to dequeue from | |
788 | * | |
789 | * Remove the tail of the list. This function does not take any locks | |
790 | * so must be used with appropriate locks held only. The tail item is | |
791 | * returned or %NULL if the list is empty. | |
792 | */ | |
793 | extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); | |
794 | static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) | |
795 | { | |
796 | struct sk_buff *skb = skb_peek_tail(list); | |
797 | if (skb) | |
798 | __skb_unlink(skb, list); | |
799 | return skb; | |
800 | } | |
801 | ||
802 | ||
803 | static inline int skb_is_nonlinear(const struct sk_buff *skb) | |
804 | { | |
805 | return skb->data_len; | |
806 | } | |
807 | ||
808 | static inline unsigned int skb_headlen(const struct sk_buff *skb) | |
809 | { | |
810 | return skb->len - skb->data_len; | |
811 | } | |
812 | ||
813 | static inline int skb_pagelen(const struct sk_buff *skb) | |
814 | { | |
815 | int i, len = 0; | |
816 | ||
817 | for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) | |
818 | len += skb_shinfo(skb)->frags[i].size; | |
819 | return len + skb_headlen(skb); | |
820 | } | |
821 | ||
822 | static inline void skb_fill_page_desc(struct sk_buff *skb, int i, | |
823 | struct page *page, int off, int size) | |
824 | { | |
825 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; | |
826 | ||
827 | frag->page = page; | |
828 | frag->page_offset = off; | |
829 | frag->size = size; | |
830 | skb_shinfo(skb)->nr_frags = i + 1; | |
831 | } | |
832 | ||
833 | #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) | |
834 | #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list) | |
835 | #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) | |
836 | ||
837 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
838 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
839 | { | |
840 | return skb->head + skb->tail; | |
841 | } | |
842 | ||
843 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
844 | { | |
845 | skb->tail = skb->data - skb->head; | |
846 | } | |
847 | ||
848 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
849 | { | |
850 | skb_reset_tail_pointer(skb); | |
851 | skb->tail += offset; | |
852 | } | |
853 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ | |
854 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
855 | { | |
856 | return skb->tail; | |
857 | } | |
858 | ||
859 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
860 | { | |
861 | skb->tail = skb->data; | |
862 | } | |
863 | ||
864 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
865 | { | |
866 | skb->tail = skb->data + offset; | |
867 | } | |
868 | ||
869 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ | |
870 | ||
871 | /* | |
872 | * Add data to an sk_buff | |
873 | */ | |
874 | static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) | |
875 | { | |
876 | unsigned char *tmp = skb_tail_pointer(skb); | |
877 | SKB_LINEAR_ASSERT(skb); | |
878 | skb->tail += len; | |
879 | skb->len += len; | |
880 | return tmp; | |
881 | } | |
882 | ||
883 | /** | |
884 | * skb_put - add data to a buffer | |
885 | * @skb: buffer to use | |
886 | * @len: amount of data to add | |
887 | * | |
888 | * This function extends the used data area of the buffer. If this would | |
889 | * exceed the total buffer size the kernel will panic. A pointer to the | |
890 | * first byte of the extra data is returned. | |
891 | */ | |
892 | static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len) | |
893 | { | |
894 | unsigned char *tmp = skb_tail_pointer(skb); | |
895 | SKB_LINEAR_ASSERT(skb); | |
896 | skb->tail += len; | |
897 | skb->len += len; | |
898 | if (unlikely(skb->tail > skb->end)) | |
899 | skb_over_panic(skb, len, current_text_addr()); | |
900 | return tmp; | |
901 | } | |
902 | ||
903 | static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) | |
904 | { | |
905 | skb->data -= len; | |
906 | skb->len += len; | |
907 | return skb->data; | |
908 | } | |
909 | ||
910 | /** | |
911 | * skb_push - add data to the start of a buffer | |
912 | * @skb: buffer to use | |
913 | * @len: amount of data to add | |
914 | * | |
915 | * This function extends the used data area of the buffer at the buffer | |
916 | * start. If this would exceed the total buffer headroom the kernel will | |
917 | * panic. A pointer to the first byte of the extra data is returned. | |
918 | */ | |
919 | static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len) | |
920 | { | |
921 | skb->data -= len; | |
922 | skb->len += len; | |
923 | if (unlikely(skb->data<skb->head)) | |
924 | skb_under_panic(skb, len, current_text_addr()); | |
925 | return skb->data; | |
926 | } | |
927 | ||
928 | static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) | |
929 | { | |
930 | skb->len -= len; | |
931 | BUG_ON(skb->len < skb->data_len); | |
932 | return skb->data += len; | |
933 | } | |
934 | ||
935 | /** | |
936 | * skb_pull - remove data from the start of a buffer | |
937 | * @skb: buffer to use | |
938 | * @len: amount of data to remove | |
939 | * | |
940 | * This function removes data from the start of a buffer, returning | |
941 | * the memory to the headroom. A pointer to the next data in the buffer | |
942 | * is returned. Once the data has been pulled future pushes will overwrite | |
943 | * the old data. | |
944 | */ | |
945 | static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) | |
946 | { | |
947 | return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); | |
948 | } | |
949 | ||
950 | extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); | |
951 | ||
952 | static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) | |
953 | { | |
954 | if (len > skb_headlen(skb) && | |
955 | !__pskb_pull_tail(skb, len-skb_headlen(skb))) | |
956 | return NULL; | |
957 | skb->len -= len; | |
958 | return skb->data += len; | |
959 | } | |
960 | ||
961 | static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) | |
962 | { | |
963 | return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); | |
964 | } | |
965 | ||
966 | static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) | |
967 | { | |
968 | if (likely(len <= skb_headlen(skb))) | |
969 | return 1; | |
970 | if (unlikely(len > skb->len)) | |
971 | return 0; | |
972 | return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL; | |
973 | } | |
974 | ||
975 | /** | |
976 | * skb_headroom - bytes at buffer head | |
977 | * @skb: buffer to check | |
978 | * | |
979 | * Return the number of bytes of free space at the head of an &sk_buff. | |
980 | */ | |
981 | static inline int skb_headroom(const struct sk_buff *skb) | |
982 | { | |
983 | return skb->data - skb->head; | |
984 | } | |
985 | ||
986 | /** | |
987 | * skb_tailroom - bytes at buffer end | |
988 | * @skb: buffer to check | |
989 | * | |
990 | * Return the number of bytes of free space at the tail of an sk_buff | |
991 | */ | |
992 | static inline int skb_tailroom(const struct sk_buff *skb) | |
993 | { | |
994 | return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; | |
995 | } | |
996 | ||
997 | /** | |
998 | * skb_reserve - adjust headroom | |
999 | * @skb: buffer to alter | |
1000 | * @len: bytes to move | |
1001 | * | |
1002 | * Increase the headroom of an empty &sk_buff by reducing the tail | |
1003 | * room. This is only allowed for an empty buffer. | |
1004 | */ | |
1005 | static inline void skb_reserve(struct sk_buff *skb, int len) | |
1006 | { | |
1007 | skb->data += len; | |
1008 | skb->tail += len; | |
1009 | } | |
1010 | ||
1011 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
1012 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) | |
1013 | { | |
1014 | return skb->head + skb->transport_header; | |
1015 | } | |
1016 | ||
1017 | static inline void skb_reset_transport_header(struct sk_buff *skb) | |
1018 | { | |
1019 | skb->transport_header = skb->data - skb->head; | |
1020 | } | |
1021 | ||
1022 | static inline void skb_set_transport_header(struct sk_buff *skb, | |
1023 | const int offset) | |
1024 | { | |
1025 | skb_reset_transport_header(skb); | |
1026 | skb->transport_header += offset; | |
1027 | } | |
1028 | ||
1029 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) | |
1030 | { | |
1031 | return skb->head + skb->network_header; | |
1032 | } | |
1033 | ||
1034 | static inline void skb_reset_network_header(struct sk_buff *skb) | |
1035 | { | |
1036 | skb->network_header = skb->data - skb->head; | |
1037 | } | |
1038 | ||
1039 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) | |
1040 | { | |
1041 | skb_reset_network_header(skb); | |
1042 | skb->network_header += offset; | |
1043 | } | |
1044 | ||
1045 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) | |
1046 | { | |
1047 | return skb->head + skb->mac_header; | |
1048 | } | |
1049 | ||
1050 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) | |
1051 | { | |
1052 | return skb->mac_header != ~0U; | |
1053 | } | |
1054 | ||
1055 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1056 | { | |
1057 | skb->mac_header = skb->data - skb->head; | |
1058 | } | |
1059 | ||
1060 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1061 | { | |
1062 | skb_reset_mac_header(skb); | |
1063 | skb->mac_header += offset; | |
1064 | } | |
1065 | ||
1066 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ | |
1067 | ||
1068 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) | |
1069 | { | |
1070 | return skb->transport_header; | |
1071 | } | |
1072 | ||
1073 | static inline void skb_reset_transport_header(struct sk_buff *skb) | |
1074 | { | |
1075 | skb->transport_header = skb->data; | |
1076 | } | |
1077 | ||
1078 | static inline void skb_set_transport_header(struct sk_buff *skb, | |
1079 | const int offset) | |
1080 | { | |
1081 | skb->transport_header = skb->data + offset; | |
1082 | } | |
1083 | ||
1084 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) | |
1085 | { | |
1086 | return skb->network_header; | |
1087 | } | |
1088 | ||
1089 | static inline void skb_reset_network_header(struct sk_buff *skb) | |
1090 | { | |
1091 | skb->network_header = skb->data; | |
1092 | } | |
1093 | ||
1094 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) | |
1095 | { | |
1096 | skb->network_header = skb->data + offset; | |
1097 | } | |
1098 | ||
1099 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) | |
1100 | { | |
1101 | return skb->mac_header; | |
1102 | } | |
1103 | ||
1104 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) | |
1105 | { | |
1106 | return skb->mac_header != NULL; | |
1107 | } | |
1108 | ||
1109 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1110 | { | |
1111 | skb->mac_header = skb->data; | |
1112 | } | |
1113 | ||
1114 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1115 | { | |
1116 | skb->mac_header = skb->data + offset; | |
1117 | } | |
1118 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ | |
1119 | ||
1120 | static inline int skb_transport_offset(const struct sk_buff *skb) | |
1121 | { | |
1122 | return skb_transport_header(skb) - skb->data; | |
1123 | } | |
1124 | ||
1125 | static inline u32 skb_network_header_len(const struct sk_buff *skb) | |
1126 | { | |
1127 | return skb->transport_header - skb->network_header; | |
1128 | } | |
1129 | ||
1130 | static inline int skb_network_offset(const struct sk_buff *skb) | |
1131 | { | |
1132 | return skb_network_header(skb) - skb->data; | |
1133 | } | |
1134 | ||
1135 | /* | |
1136 | * CPUs often take a performance hit when accessing unaligned memory | |
1137 | * locations. The actual performance hit varies, it can be small if the | |
1138 | * hardware handles it or large if we have to take an exception and fix it | |
1139 | * in software. | |
1140 | * | |
1141 | * Since an ethernet header is 14 bytes network drivers often end up with | |
1142 | * the IP header at an unaligned offset. The IP header can be aligned by | |
1143 | * shifting the start of the packet by 2 bytes. Drivers should do this | |
1144 | * with: | |
1145 | * | |
1146 | * skb_reserve(NET_IP_ALIGN); | |
1147 | * | |
1148 | * The downside to this alignment of the IP header is that the DMA is now | |
1149 | * unaligned. On some architectures the cost of an unaligned DMA is high | |
1150 | * and this cost outweighs the gains made by aligning the IP header. | |
1151 | * | |
1152 | * Since this trade off varies between architectures, we allow NET_IP_ALIGN | |
1153 | * to be overridden. | |
1154 | */ | |
1155 | #ifndef NET_IP_ALIGN | |
1156 | #define NET_IP_ALIGN 2 | |
1157 | #endif | |
1158 | ||
1159 | /* | |
1160 | * The networking layer reserves some headroom in skb data (via | |
1161 | * dev_alloc_skb). This is used to avoid having to reallocate skb data when | |
1162 | * the header has to grow. In the default case, if the header has to grow | |
1163 | * 16 bytes or less we avoid the reallocation. | |
1164 | * | |
1165 | * Unfortunately this headroom changes the DMA alignment of the resulting | |
1166 | * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive | |
1167 | * on some architectures. An architecture can override this value, | |
1168 | * perhaps setting it to a cacheline in size (since that will maintain | |
1169 | * cacheline alignment of the DMA). It must be a power of 2. | |
1170 | * | |
1171 | * Various parts of the networking layer expect at least 16 bytes of | |
1172 | * headroom, you should not reduce this. | |
1173 | */ | |
1174 | #ifndef NET_SKB_PAD | |
1175 | #define NET_SKB_PAD 16 | |
1176 | #endif | |
1177 | ||
1178 | extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); | |
1179 | ||
1180 | static inline void __skb_trim(struct sk_buff *skb, unsigned int len) | |
1181 | { | |
1182 | if (unlikely(skb->data_len)) { | |
1183 | WARN_ON(1); | |
1184 | return; | |
1185 | } | |
1186 | skb->len = len; | |
1187 | skb_set_tail_pointer(skb, len); | |
1188 | } | |
1189 | ||
1190 | /** | |
1191 | * skb_trim - remove end from a buffer | |
1192 | * @skb: buffer to alter | |
1193 | * @len: new length | |
1194 | * | |
1195 | * Cut the length of a buffer down by removing data from the tail. If | |
1196 | * the buffer is already under the length specified it is not modified. | |
1197 | * The skb must be linear. | |
1198 | */ | |
1199 | static inline void skb_trim(struct sk_buff *skb, unsigned int len) | |
1200 | { | |
1201 | if (skb->len > len) | |
1202 | __skb_trim(skb, len); | |
1203 | } | |
1204 | ||
1205 | ||
1206 | static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) | |
1207 | { | |
1208 | if (skb->data_len) | |
1209 | return ___pskb_trim(skb, len); | |
1210 | __skb_trim(skb, len); | |
1211 | return 0; | |
1212 | } | |
1213 | ||
1214 | static inline int pskb_trim(struct sk_buff *skb, unsigned int len) | |
1215 | { | |
1216 | return (len < skb->len) ? __pskb_trim(skb, len) : 0; | |
1217 | } | |
1218 | ||
1219 | /** | |
1220 | * pskb_trim_unique - remove end from a paged unique (not cloned) buffer | |
1221 | * @skb: buffer to alter | |
1222 | * @len: new length | |
1223 | * | |
1224 | * This is identical to pskb_trim except that the caller knows that | |
1225 | * the skb is not cloned so we should never get an error due to out- | |
1226 | * of-memory. | |
1227 | */ | |
1228 | static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) | |
1229 | { | |
1230 | int err = pskb_trim(skb, len); | |
1231 | BUG_ON(err); | |
1232 | } | |
1233 | ||
1234 | /** | |
1235 | * skb_orphan - orphan a buffer | |
1236 | * @skb: buffer to orphan | |
1237 | * | |
1238 | * If a buffer currently has an owner then we call the owner's | |
1239 | * destructor function and make the @skb unowned. The buffer continues | |
1240 | * to exist but is no longer charged to its former owner. | |
1241 | */ | |
1242 | static inline void skb_orphan(struct sk_buff *skb) | |
1243 | { | |
1244 | if (skb->destructor) | |
1245 | skb->destructor(skb); | |
1246 | skb->destructor = NULL; | |
1247 | skb->sk = NULL; | |
1248 | } | |
1249 | ||
1250 | /** | |
1251 | * __skb_queue_purge - empty a list | |
1252 | * @list: list to empty | |
1253 | * | |
1254 | * Delete all buffers on an &sk_buff list. Each buffer is removed from | |
1255 | * the list and one reference dropped. This function does not take the | |
1256 | * list lock and the caller must hold the relevant locks to use it. | |
1257 | */ | |
1258 | extern void skb_queue_purge(struct sk_buff_head *list); | |
1259 | static inline void __skb_queue_purge(struct sk_buff_head *list) | |
1260 | { | |
1261 | struct sk_buff *skb; | |
1262 | while ((skb = __skb_dequeue(list)) != NULL) | |
1263 | kfree_skb(skb); | |
1264 | } | |
1265 | ||
1266 | /** | |
1267 | * __dev_alloc_skb - allocate an skbuff for receiving | |
1268 | * @length: length to allocate | |
1269 | * @gfp_mask: get_free_pages mask, passed to alloc_skb | |
1270 | * | |
1271 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
1272 | * buffer has unspecified headroom built in. Users should allocate | |
1273 | * the headroom they think they need without accounting for the | |
1274 | * built in space. The built in space is used for optimisations. | |
1275 | * | |
1276 | * %NULL is returned if there is no free memory. | |
1277 | */ | |
1278 | static inline struct sk_buff *__dev_alloc_skb(unsigned int length, | |
1279 | gfp_t gfp_mask) | |
1280 | { | |
1281 | struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); | |
1282 | if (likely(skb)) | |
1283 | skb_reserve(skb, NET_SKB_PAD); | |
1284 | return skb; | |
1285 | } | |
1286 | ||
1287 | /** | |
1288 | * dev_alloc_skb - allocate an skbuff for receiving | |
1289 | * @length: length to allocate | |
1290 | * | |
1291 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
1292 | * buffer has unspecified headroom built in. Users should allocate | |
1293 | * the headroom they think they need without accounting for the | |
1294 | * built in space. The built in space is used for optimisations. | |
1295 | * | |
1296 | * %NULL is returned if there is no free memory. Although this function | |
1297 | * allocates memory it can be called from an interrupt. | |
1298 | */ | |
1299 | static inline struct sk_buff *dev_alloc_skb(unsigned int length) | |
1300 | { | |
1301 | return __dev_alloc_skb(length, GFP_ATOMIC); | |
1302 | } | |
1303 | ||
1304 | extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev, | |
1305 | unsigned int length, gfp_t gfp_mask); | |
1306 | ||
1307 | /** | |
1308 | * netdev_alloc_skb - allocate an skbuff for rx on a specific device | |
1309 | * @dev: network device to receive on | |
1310 | * @length: length to allocate | |
1311 | * | |
1312 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
1313 | * buffer has unspecified headroom built in. Users should allocate | |
1314 | * the headroom they think they need without accounting for the | |
1315 | * built in space. The built in space is used for optimisations. | |
1316 | * | |
1317 | * %NULL is returned if there is no free memory. Although this function | |
1318 | * allocates memory it can be called from an interrupt. | |
1319 | */ | |
1320 | static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, | |
1321 | unsigned int length) | |
1322 | { | |
1323 | return __netdev_alloc_skb(dev, length, GFP_ATOMIC); | |
1324 | } | |
1325 | ||
1326 | /** | |
1327 | * skb_clone_writable - is the header of a clone writable | |
1328 | * @skb: buffer to check | |
1329 | * @len: length up to which to write | |
1330 | * | |
1331 | * Returns true if modifying the header part of the cloned buffer | |
1332 | * does not requires the data to be copied. | |
1333 | */ | |
1334 | static inline int skb_clone_writable(struct sk_buff *skb, int len) | |
1335 | { | |
1336 | return !skb_header_cloned(skb) && | |
1337 | skb_headroom(skb) + len <= skb->hdr_len; | |
1338 | } | |
1339 | ||
1340 | /** | |
1341 | * skb_cow - copy header of skb when it is required | |
1342 | * @skb: buffer to cow | |
1343 | * @headroom: needed headroom | |
1344 | * | |
1345 | * If the skb passed lacks sufficient headroom or its data part | |
1346 | * is shared, data is reallocated. If reallocation fails, an error | |
1347 | * is returned and original skb is not changed. | |
1348 | * | |
1349 | * The result is skb with writable area skb->head...skb->tail | |
1350 | * and at least @headroom of space at head. | |
1351 | */ | |
1352 | static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) | |
1353 | { | |
1354 | int delta = (headroom > NET_SKB_PAD ? headroom : NET_SKB_PAD) - | |
1355 | skb_headroom(skb); | |
1356 | ||
1357 | if (delta < 0) | |
1358 | delta = 0; | |
1359 | ||
1360 | if (delta || skb_cloned(skb)) | |
1361 | return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) & | |
1362 | ~(NET_SKB_PAD-1), 0, GFP_ATOMIC); | |
1363 | return 0; | |
1364 | } | |
1365 | ||
1366 | /** | |
1367 | * skb_padto - pad an skbuff up to a minimal size | |
1368 | * @skb: buffer to pad | |
1369 | * @len: minimal length | |
1370 | * | |
1371 | * Pads up a buffer to ensure the trailing bytes exist and are | |
1372 | * blanked. If the buffer already contains sufficient data it | |
1373 | * is untouched. Otherwise it is extended. Returns zero on | |
1374 | * success. The skb is freed on error. | |
1375 | */ | |
1376 | ||
1377 | static inline int skb_padto(struct sk_buff *skb, unsigned int len) | |
1378 | { | |
1379 | unsigned int size = skb->len; | |
1380 | if (likely(size >= len)) | |
1381 | return 0; | |
1382 | return skb_pad(skb, len-size); | |
1383 | } | |
1384 | ||
1385 | static inline int skb_add_data(struct sk_buff *skb, | |
1386 | char __user *from, int copy) | |
1387 | { | |
1388 | const int off = skb->len; | |
1389 | ||
1390 | if (skb->ip_summed == CHECKSUM_NONE) { | |
1391 | int err = 0; | |
1392 | __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), | |
1393 | copy, 0, &err); | |
1394 | if (!err) { | |
1395 | skb->csum = csum_block_add(skb->csum, csum, off); | |
1396 | return 0; | |
1397 | } | |
1398 | } else if (!copy_from_user(skb_put(skb, copy), from, copy)) | |
1399 | return 0; | |
1400 | ||
1401 | __skb_trim(skb, off); | |
1402 | return -EFAULT; | |
1403 | } | |
1404 | ||
1405 | static inline int skb_can_coalesce(struct sk_buff *skb, int i, | |
1406 | struct page *page, int off) | |
1407 | { | |
1408 | if (i) { | |
1409 | struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; | |
1410 | ||
1411 | return page == frag->page && | |
1412 | off == frag->page_offset + frag->size; | |
1413 | } | |
1414 | return 0; | |
1415 | } | |
1416 | ||
1417 | static inline int __skb_linearize(struct sk_buff *skb) | |
1418 | { | |
1419 | return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; | |
1420 | } | |
1421 | ||
1422 | /** | |
1423 | * skb_linearize - convert paged skb to linear one | |
1424 | * @skb: buffer to linarize | |
1425 | * | |
1426 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
1427 | * is returned and the old skb data released. | |
1428 | */ | |
1429 | static inline int skb_linearize(struct sk_buff *skb) | |
1430 | { | |
1431 | return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; | |
1432 | } | |
1433 | ||
1434 | /** | |
1435 | * skb_linearize_cow - make sure skb is linear and writable | |
1436 | * @skb: buffer to process | |
1437 | * | |
1438 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
1439 | * is returned and the old skb data released. | |
1440 | */ | |
1441 | static inline int skb_linearize_cow(struct sk_buff *skb) | |
1442 | { | |
1443 | return skb_is_nonlinear(skb) || skb_cloned(skb) ? | |
1444 | __skb_linearize(skb) : 0; | |
1445 | } | |
1446 | ||
1447 | /** | |
1448 | * skb_postpull_rcsum - update checksum for received skb after pull | |
1449 | * @skb: buffer to update | |
1450 | * @start: start of data before pull | |
1451 | * @len: length of data pulled | |
1452 | * | |
1453 | * After doing a pull on a received packet, you need to call this to | |
1454 | * update the CHECKSUM_COMPLETE checksum, or set ip_summed to | |
1455 | * CHECKSUM_NONE so that it can be recomputed from scratch. | |
1456 | */ | |
1457 | ||
1458 | static inline void skb_postpull_rcsum(struct sk_buff *skb, | |
1459 | const void *start, unsigned int len) | |
1460 | { | |
1461 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1462 | skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); | |
1463 | } | |
1464 | ||
1465 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); | |
1466 | ||
1467 | /** | |
1468 | * pskb_trim_rcsum - trim received skb and update checksum | |
1469 | * @skb: buffer to trim | |
1470 | * @len: new length | |
1471 | * | |
1472 | * This is exactly the same as pskb_trim except that it ensures the | |
1473 | * checksum of received packets are still valid after the operation. | |
1474 | */ | |
1475 | ||
1476 | static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) | |
1477 | { | |
1478 | if (likely(len >= skb->len)) | |
1479 | return 0; | |
1480 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1481 | skb->ip_summed = CHECKSUM_NONE; | |
1482 | return __pskb_trim(skb, len); | |
1483 | } | |
1484 | ||
1485 | #define skb_queue_walk(queue, skb) \ | |
1486 | for (skb = (queue)->next; \ | |
1487 | prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \ | |
1488 | skb = skb->next) | |
1489 | ||
1490 | #define skb_queue_walk_safe(queue, skb, tmp) \ | |
1491 | for (skb = (queue)->next, tmp = skb->next; \ | |
1492 | skb != (struct sk_buff *)(queue); \ | |
1493 | skb = tmp, tmp = skb->next) | |
1494 | ||
1495 | #define skb_queue_reverse_walk(queue, skb) \ | |
1496 | for (skb = (queue)->prev; \ | |
1497 | prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \ | |
1498 | skb = skb->prev) | |
1499 | ||
1500 | ||
1501 | extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, | |
1502 | int noblock, int *err); | |
1503 | extern unsigned int datagram_poll(struct file *file, struct socket *sock, | |
1504 | struct poll_table_struct *wait); | |
1505 | extern int skb_copy_datagram_iovec(const struct sk_buff *from, | |
1506 | int offset, struct iovec *to, | |
1507 | int size); | |
1508 | extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, | |
1509 | int hlen, | |
1510 | struct iovec *iov); | |
1511 | extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb); | |
1512 | extern void skb_kill_datagram(struct sock *sk, struct sk_buff *skb, | |
1513 | unsigned int flags); | |
1514 | extern __wsum skb_checksum(const struct sk_buff *skb, int offset, | |
1515 | int len, __wsum csum); | |
1516 | extern int skb_copy_bits(const struct sk_buff *skb, int offset, | |
1517 | void *to, int len); | |
1518 | extern int skb_store_bits(struct sk_buff *skb, int offset, | |
1519 | const void *from, int len); | |
1520 | extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, | |
1521 | int offset, u8 *to, int len, | |
1522 | __wsum csum); | |
1523 | extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); | |
1524 | extern void skb_split(struct sk_buff *skb, | |
1525 | struct sk_buff *skb1, const u32 len); | |
1526 | ||
1527 | extern struct sk_buff *skb_segment(struct sk_buff *skb, int features); | |
1528 | ||
1529 | static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, | |
1530 | int len, void *buffer) | |
1531 | { | |
1532 | int hlen = skb_headlen(skb); | |
1533 | ||
1534 | if (hlen - offset >= len) | |
1535 | return skb->data + offset; | |
1536 | ||
1537 | if (skb_copy_bits(skb, offset, buffer, len) < 0) | |
1538 | return NULL; | |
1539 | ||
1540 | return buffer; | |
1541 | } | |
1542 | ||
1543 | static inline void skb_copy_from_linear_data(const struct sk_buff *skb, | |
1544 | void *to, | |
1545 | const unsigned int len) | |
1546 | { | |
1547 | memcpy(to, skb->data, len); | |
1548 | } | |
1549 | ||
1550 | static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, | |
1551 | const int offset, void *to, | |
1552 | const unsigned int len) | |
1553 | { | |
1554 | memcpy(to, skb->data + offset, len); | |
1555 | } | |
1556 | ||
1557 | static inline void skb_copy_to_linear_data(struct sk_buff *skb, | |
1558 | const void *from, | |
1559 | const unsigned int len) | |
1560 | { | |
1561 | memcpy(skb->data, from, len); | |
1562 | } | |
1563 | ||
1564 | static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, | |
1565 | const int offset, | |
1566 | const void *from, | |
1567 | const unsigned int len) | |
1568 | { | |
1569 | memcpy(skb->data + offset, from, len); | |
1570 | } | |
1571 | ||
1572 | extern void skb_init(void); | |
1573 | ||
1574 | /** | |
1575 | * skb_get_timestamp - get timestamp from a skb | |
1576 | * @skb: skb to get stamp from | |
1577 | * @stamp: pointer to struct timeval to store stamp in | |
1578 | * | |
1579 | * Timestamps are stored in the skb as offsets to a base timestamp. | |
1580 | * This function converts the offset back to a struct timeval and stores | |
1581 | * it in stamp. | |
1582 | */ | |
1583 | static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp) | |
1584 | { | |
1585 | *stamp = ktime_to_timeval(skb->tstamp); | |
1586 | } | |
1587 | ||
1588 | static inline void __net_timestamp(struct sk_buff *skb) | |
1589 | { | |
1590 | skb->tstamp = ktime_get_real(); | |
1591 | } | |
1592 | ||
1593 | static inline ktime_t net_timedelta(ktime_t t) | |
1594 | { | |
1595 | return ktime_sub(ktime_get_real(), t); | |
1596 | } | |
1597 | ||
1598 | static inline ktime_t net_invalid_timestamp(void) | |
1599 | { | |
1600 | return ktime_set(0, 0); | |
1601 | } | |
1602 | ||
1603 | extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); | |
1604 | extern __sum16 __skb_checksum_complete(struct sk_buff *skb); | |
1605 | ||
1606 | static inline int skb_csum_unnecessary(const struct sk_buff *skb) | |
1607 | { | |
1608 | return skb->ip_summed & CHECKSUM_UNNECESSARY; | |
1609 | } | |
1610 | ||
1611 | /** | |
1612 | * skb_checksum_complete - Calculate checksum of an entire packet | |
1613 | * @skb: packet to process | |
1614 | * | |
1615 | * This function calculates the checksum over the entire packet plus | |
1616 | * the value of skb->csum. The latter can be used to supply the | |
1617 | * checksum of a pseudo header as used by TCP/UDP. It returns the | |
1618 | * checksum. | |
1619 | * | |
1620 | * For protocols that contain complete checksums such as ICMP/TCP/UDP, | |
1621 | * this function can be used to verify that checksum on received | |
1622 | * packets. In that case the function should return zero if the | |
1623 | * checksum is correct. In particular, this function will return zero | |
1624 | * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the | |
1625 | * hardware has already verified the correctness of the checksum. | |
1626 | */ | |
1627 | static inline unsigned int skb_checksum_complete(struct sk_buff *skb) | |
1628 | { | |
1629 | return skb_csum_unnecessary(skb) ? | |
1630 | 0 : __skb_checksum_complete(skb); | |
1631 | } | |
1632 | ||
1633 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1634 | extern void nf_conntrack_destroy(struct nf_conntrack *nfct); | |
1635 | static inline void nf_conntrack_put(struct nf_conntrack *nfct) | |
1636 | { | |
1637 | if (nfct && atomic_dec_and_test(&nfct->use)) | |
1638 | nf_conntrack_destroy(nfct); | |
1639 | } | |
1640 | static inline void nf_conntrack_get(struct nf_conntrack *nfct) | |
1641 | { | |
1642 | if (nfct) | |
1643 | atomic_inc(&nfct->use); | |
1644 | } | |
1645 | static inline void nf_conntrack_get_reasm(struct sk_buff *skb) | |
1646 | { | |
1647 | if (skb) | |
1648 | atomic_inc(&skb->users); | |
1649 | } | |
1650 | static inline void nf_conntrack_put_reasm(struct sk_buff *skb) | |
1651 | { | |
1652 | if (skb) | |
1653 | kfree_skb(skb); | |
1654 | } | |
1655 | #endif | |
1656 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1657 | static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) | |
1658 | { | |
1659 | if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) | |
1660 | kfree(nf_bridge); | |
1661 | } | |
1662 | static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) | |
1663 | { | |
1664 | if (nf_bridge) | |
1665 | atomic_inc(&nf_bridge->use); | |
1666 | } | |
1667 | #endif /* CONFIG_BRIDGE_NETFILTER */ | |
1668 | static inline void nf_reset(struct sk_buff *skb) | |
1669 | { | |
1670 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1671 | nf_conntrack_put(skb->nfct); | |
1672 | skb->nfct = NULL; | |
1673 | nf_conntrack_put_reasm(skb->nfct_reasm); | |
1674 | skb->nfct_reasm = NULL; | |
1675 | #endif | |
1676 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1677 | nf_bridge_put(skb->nf_bridge); | |
1678 | skb->nf_bridge = NULL; | |
1679 | #endif | |
1680 | } | |
1681 | ||
1682 | /* Note: This doesn't put any conntrack and bridge info in dst. */ | |
1683 | static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src) | |
1684 | { | |
1685 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1686 | dst->nfct = src->nfct; | |
1687 | nf_conntrack_get(src->nfct); | |
1688 | dst->nfctinfo = src->nfctinfo; | |
1689 | dst->nfct_reasm = src->nfct_reasm; | |
1690 | nf_conntrack_get_reasm(src->nfct_reasm); | |
1691 | #endif | |
1692 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1693 | dst->nf_bridge = src->nf_bridge; | |
1694 | nf_bridge_get(src->nf_bridge); | |
1695 | #endif | |
1696 | } | |
1697 | ||
1698 | static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) | |
1699 | { | |
1700 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1701 | nf_conntrack_put(dst->nfct); | |
1702 | nf_conntrack_put_reasm(dst->nfct_reasm); | |
1703 | #endif | |
1704 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1705 | nf_bridge_put(dst->nf_bridge); | |
1706 | #endif | |
1707 | __nf_copy(dst, src); | |
1708 | } | |
1709 | ||
1710 | #ifdef CONFIG_NETWORK_SECMARK | |
1711 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
1712 | { | |
1713 | to->secmark = from->secmark; | |
1714 | } | |
1715 | ||
1716 | static inline void skb_init_secmark(struct sk_buff *skb) | |
1717 | { | |
1718 | skb->secmark = 0; | |
1719 | } | |
1720 | #else | |
1721 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
1722 | { } | |
1723 | ||
1724 | static inline void skb_init_secmark(struct sk_buff *skb) | |
1725 | { } | |
1726 | #endif | |
1727 | ||
1728 | static inline int skb_is_gso(const struct sk_buff *skb) | |
1729 | { | |
1730 | return skb_shinfo(skb)->gso_size; | |
1731 | } | |
1732 | ||
1733 | static inline void skb_forward_csum(struct sk_buff *skb) | |
1734 | { | |
1735 | /* Unfortunately we don't support this one. Any brave souls? */ | |
1736 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1737 | skb->ip_summed = CHECKSUM_NONE; | |
1738 | } | |
1739 | ||
1740 | #endif /* __KERNEL__ */ | |
1741 | #endif /* _LINUX_SKBUFF_H */ |