]>
Commit | Line | Data |
---|---|---|
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) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) | |
45 | #define SKB_MAX_ORDER(X, ORDER) \ | |
46 | SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) | |
47 | #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) | |
48 | #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) | |
49 | ||
50 | /* A. Checksumming of received packets by device. | |
51 | * | |
52 | * NONE: device failed to checksum this packet. | |
53 | * skb->csum is undefined. | |
54 | * | |
55 | * UNNECESSARY: device parsed packet and wouldbe verified checksum. | |
56 | * skb->csum is undefined. | |
57 | * It is bad option, but, unfortunately, many of vendors do this. | |
58 | * Apparently with secret goal to sell you new device, when you | |
59 | * will add new protocol to your host. F.e. IPv6. 8) | |
60 | * | |
61 | * COMPLETE: the most generic way. Device supplied checksum of _all_ | |
62 | * the packet as seen by netif_rx in skb->csum. | |
63 | * NOTE: Even if device supports only some protocols, but | |
64 | * is able to produce some skb->csum, it MUST use COMPLETE, | |
65 | * not UNNECESSARY. | |
66 | * | |
67 | * PARTIAL: identical to the case for output below. This may occur | |
68 | * on a packet received directly from another Linux OS, e.g., | |
69 | * a virtualised Linux kernel on the same host. The packet can | |
70 | * be treated in the same way as UNNECESSARY except that on | |
71 | * output (i.e., forwarding) the checksum must be filled in | |
72 | * by the OS or the hardware. | |
73 | * | |
74 | * B. Checksumming on output. | |
75 | * | |
76 | * NONE: skb is checksummed by protocol or csum is not required. | |
77 | * | |
78 | * PARTIAL: device is required to csum packet as seen by hard_start_xmit | |
79 | * from skb->csum_start to the end and to record the checksum | |
80 | * at skb->csum_start + skb->csum_offset. | |
81 | * | |
82 | * Device must show its capabilities in dev->features, set | |
83 | * at device setup time. | |
84 | * NETIF_F_HW_CSUM - it is clever device, it is able to checksum | |
85 | * everything. | |
86 | * NETIF_F_NO_CSUM - loopback or reliable single hop media. | |
87 | * NETIF_F_IP_CSUM - device is dumb. It is able to csum only | |
88 | * TCP/UDP over IPv4. Sigh. Vendors like this | |
89 | * way by an unknown reason. Though, see comment above | |
90 | * about CHECKSUM_UNNECESSARY. 8) | |
91 | * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. | |
92 | * | |
93 | * Any questions? No questions, good. --ANK | |
94 | */ | |
95 | ||
96 | struct net_device; | |
97 | struct scatterlist; | |
98 | struct pipe_inode_info; | |
99 | ||
100 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
101 | struct nf_conntrack { | |
102 | atomic_t use; | |
103 | }; | |
104 | #endif | |
105 | ||
106 | #ifdef CONFIG_BRIDGE_NETFILTER | |
107 | struct nf_bridge_info { | |
108 | atomic_t use; | |
109 | struct net_device *physindev; | |
110 | struct net_device *physoutdev; | |
111 | unsigned int mask; | |
112 | unsigned long data[32 / sizeof(unsigned long)]; | |
113 | }; | |
114 | #endif | |
115 | ||
116 | struct sk_buff_head { | |
117 | /* These two members must be first. */ | |
118 | struct sk_buff *next; | |
119 | struct sk_buff *prev; | |
120 | ||
121 | __u32 qlen; | |
122 | spinlock_t lock; | |
123 | }; | |
124 | ||
125 | struct sk_buff; | |
126 | ||
127 | /* To allow 64K frame to be packed as single skb without frag_list */ | |
128 | #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2) | |
129 | ||
130 | typedef struct skb_frag_struct skb_frag_t; | |
131 | ||
132 | struct skb_frag_struct { | |
133 | struct page *page; | |
134 | __u32 page_offset; | |
135 | __u32 size; | |
136 | }; | |
137 | ||
138 | /* This data is invariant across clones and lives at | |
139 | * the end of the header data, ie. at skb->end. | |
140 | */ | |
141 | struct skb_shared_info { | |
142 | atomic_t dataref; | |
143 | unsigned short nr_frags; | |
144 | unsigned short gso_size; | |
145 | /* Warning: this field is not always filled in (UFO)! */ | |
146 | unsigned short gso_segs; | |
147 | unsigned short gso_type; | |
148 | __be32 ip6_frag_id; | |
149 | #ifdef CONFIG_HAS_DMA | |
150 | unsigned int num_dma_maps; | |
151 | #endif | |
152 | struct sk_buff *frag_list; | |
153 | skb_frag_t frags[MAX_SKB_FRAGS]; | |
154 | #ifdef CONFIG_HAS_DMA | |
155 | dma_addr_t dma_maps[MAX_SKB_FRAGS + 1]; | |
156 | #endif | |
157 | }; | |
158 | ||
159 | /* We divide dataref into two halves. The higher 16 bits hold references | |
160 | * to the payload part of skb->data. The lower 16 bits hold references to | |
161 | * the entire skb->data. A clone of a headerless skb holds the length of | |
162 | * the header in skb->hdr_len. | |
163 | * | |
164 | * All users must obey the rule that the skb->data reference count must be | |
165 | * greater than or equal to the payload reference count. | |
166 | * | |
167 | * Holding a reference to the payload part means that the user does not | |
168 | * care about modifications to the header part of skb->data. | |
169 | */ | |
170 | #define SKB_DATAREF_SHIFT 16 | |
171 | #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) | |
172 | ||
173 | ||
174 | enum { | |
175 | SKB_FCLONE_UNAVAILABLE, | |
176 | SKB_FCLONE_ORIG, | |
177 | SKB_FCLONE_CLONE, | |
178 | }; | |
179 | ||
180 | enum { | |
181 | SKB_GSO_TCPV4 = 1 << 0, | |
182 | SKB_GSO_UDP = 1 << 1, | |
183 | ||
184 | /* This indicates the skb is from an untrusted source. */ | |
185 | SKB_GSO_DODGY = 1 << 2, | |
186 | ||
187 | /* This indicates the tcp segment has CWR set. */ | |
188 | SKB_GSO_TCP_ECN = 1 << 3, | |
189 | ||
190 | SKB_GSO_TCPV6 = 1 << 4, | |
191 | }; | |
192 | ||
193 | #if BITS_PER_LONG > 32 | |
194 | #define NET_SKBUFF_DATA_USES_OFFSET 1 | |
195 | #endif | |
196 | ||
197 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
198 | typedef unsigned int sk_buff_data_t; | |
199 | #else | |
200 | typedef unsigned char *sk_buff_data_t; | |
201 | #endif | |
202 | ||
203 | /** | |
204 | * struct sk_buff - socket buffer | |
205 | * @next: Next buffer in list | |
206 | * @prev: Previous buffer in list | |
207 | * @sk: Socket we are owned by | |
208 | * @tstamp: Time we arrived | |
209 | * @dev: Device we arrived on/are leaving by | |
210 | * @transport_header: Transport layer header | |
211 | * @network_header: Network layer header | |
212 | * @mac_header: Link layer header | |
213 | * @dst: destination entry | |
214 | * @sp: the security path, used for xfrm | |
215 | * @cb: Control buffer. Free for use by every layer. Put private vars here | |
216 | * @len: Length of actual data | |
217 | * @data_len: Data length | |
218 | * @mac_len: Length of link layer header | |
219 | * @hdr_len: writable header length of cloned skb | |
220 | * @csum: Checksum (must include start/offset pair) | |
221 | * @csum_start: Offset from skb->head where checksumming should start | |
222 | * @csum_offset: Offset from csum_start where checksum should be stored | |
223 | * @local_df: allow local fragmentation | |
224 | * @cloned: Head may be cloned (check refcnt to be sure) | |
225 | * @nohdr: Payload reference only, must not modify header | |
226 | * @pkt_type: Packet class | |
227 | * @fclone: skbuff clone status | |
228 | * @ip_summed: Driver fed us an IP checksum | |
229 | * @priority: Packet queueing priority | |
230 | * @users: User count - see {datagram,tcp}.c | |
231 | * @protocol: Packet protocol from driver | |
232 | * @truesize: Buffer size | |
233 | * @head: Head of buffer | |
234 | * @data: Data head pointer | |
235 | * @tail: Tail pointer | |
236 | * @end: End pointer | |
237 | * @destructor: Destruct function | |
238 | * @mark: Generic packet mark | |
239 | * @nfct: Associated connection, if any | |
240 | * @ipvs_property: skbuff is owned by ipvs | |
241 | * @peeked: this packet has been seen already, so stats have been | |
242 | * done for it, don't do them again | |
243 | * @nf_trace: netfilter packet trace flag | |
244 | * @nfctinfo: Relationship of this skb to the connection | |
245 | * @nfct_reasm: netfilter conntrack re-assembly pointer | |
246 | * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c | |
247 | * @iif: ifindex of device we arrived on | |
248 | * @queue_mapping: Queue mapping for multiqueue devices | |
249 | * @tc_index: Traffic control index | |
250 | * @tc_verd: traffic control verdict | |
251 | * @ndisc_nodetype: router type (from link layer) | |
252 | * @do_not_encrypt: set to prevent encryption of this frame | |
253 | * @dma_cookie: a cookie to one of several possible DMA operations | |
254 | * done by skb DMA functions | |
255 | * @secmark: security marking | |
256 | * @vlan_tci: vlan tag control information | |
257 | */ | |
258 | ||
259 | struct sk_buff { | |
260 | /* These two members must be first. */ | |
261 | struct sk_buff *next; | |
262 | struct sk_buff *prev; | |
263 | ||
264 | struct sock *sk; | |
265 | ktime_t tstamp; | |
266 | struct net_device *dev; | |
267 | ||
268 | union { | |
269 | struct dst_entry *dst; | |
270 | struct rtable *rtable; | |
271 | }; | |
272 | #ifdef CONFIG_XFRM | |
273 | struct sec_path *sp; | |
274 | #endif | |
275 | /* | |
276 | * This is the control buffer. It is free to use for every | |
277 | * layer. Please put your private variables there. If you | |
278 | * want to keep them across layers you have to do a skb_clone() | |
279 | * first. This is owned by whoever has the skb queued ATM. | |
280 | */ | |
281 | char cb[48]; | |
282 | ||
283 | unsigned int len, | |
284 | data_len; | |
285 | __u16 mac_len, | |
286 | hdr_len; | |
287 | union { | |
288 | __wsum csum; | |
289 | struct { | |
290 | __u16 csum_start; | |
291 | __u16 csum_offset; | |
292 | }; | |
293 | }; | |
294 | __u32 priority; | |
295 | __u8 local_df:1, | |
296 | cloned:1, | |
297 | ip_summed:2, | |
298 | nohdr:1, | |
299 | nfctinfo:3; | |
300 | __u8 pkt_type:3, | |
301 | fclone:2, | |
302 | ipvs_property:1, | |
303 | peeked:1, | |
304 | nf_trace:1; | |
305 | __be16 protocol; | |
306 | ||
307 | void (*destructor)(struct sk_buff *skb); | |
308 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
309 | struct nf_conntrack *nfct; | |
310 | struct sk_buff *nfct_reasm; | |
311 | #endif | |
312 | #ifdef CONFIG_BRIDGE_NETFILTER | |
313 | struct nf_bridge_info *nf_bridge; | |
314 | #endif | |
315 | ||
316 | int iif; | |
317 | __u16 queue_mapping; | |
318 | #ifdef CONFIG_NET_SCHED | |
319 | __u16 tc_index; /* traffic control index */ | |
320 | #ifdef CONFIG_NET_CLS_ACT | |
321 | __u16 tc_verd; /* traffic control verdict */ | |
322 | #endif | |
323 | #endif | |
324 | #ifdef CONFIG_IPV6_NDISC_NODETYPE | |
325 | __u8 ndisc_nodetype:2; | |
326 | #endif | |
327 | #if defined(CONFIG_MAC80211) || defined(CONFIG_MAC80211_MODULE) | |
328 | __u8 do_not_encrypt:1; | |
329 | #endif | |
330 | /* 0/13/14 bit hole */ | |
331 | ||
332 | #ifdef CONFIG_NET_DMA | |
333 | dma_cookie_t dma_cookie; | |
334 | #endif | |
335 | #ifdef CONFIG_NETWORK_SECMARK | |
336 | __u32 secmark; | |
337 | #endif | |
338 | ||
339 | __u32 mark; | |
340 | ||
341 | __u16 vlan_tci; | |
342 | ||
343 | sk_buff_data_t transport_header; | |
344 | sk_buff_data_t network_header; | |
345 | sk_buff_data_t mac_header; | |
346 | /* These elements must be at the end, see alloc_skb() for details. */ | |
347 | sk_buff_data_t tail; | |
348 | sk_buff_data_t end; | |
349 | unsigned char *head, | |
350 | *data; | |
351 | unsigned int truesize; | |
352 | atomic_t users; | |
353 | }; | |
354 | ||
355 | #ifdef __KERNEL__ | |
356 | /* | |
357 | * Handling routines are only of interest to the kernel | |
358 | */ | |
359 | #include <linux/slab.h> | |
360 | ||
361 | #include <asm/system.h> | |
362 | ||
363 | #ifdef CONFIG_HAS_DMA | |
364 | #include <linux/dma-mapping.h> | |
365 | extern int skb_dma_map(struct device *dev, struct sk_buff *skb, | |
366 | enum dma_data_direction dir); | |
367 | extern void skb_dma_unmap(struct device *dev, struct sk_buff *skb, | |
368 | enum dma_data_direction dir); | |
369 | #endif | |
370 | ||
371 | extern void kfree_skb(struct sk_buff *skb); | |
372 | extern void __kfree_skb(struct sk_buff *skb); | |
373 | extern struct sk_buff *__alloc_skb(unsigned int size, | |
374 | gfp_t priority, int fclone, int node); | |
375 | static inline struct sk_buff *alloc_skb(unsigned int size, | |
376 | gfp_t priority) | |
377 | { | |
378 | return __alloc_skb(size, priority, 0, -1); | |
379 | } | |
380 | ||
381 | static inline struct sk_buff *alloc_skb_fclone(unsigned int size, | |
382 | gfp_t priority) | |
383 | { | |
384 | return __alloc_skb(size, priority, 1, -1); | |
385 | } | |
386 | ||
387 | extern int skb_recycle_check(struct sk_buff *skb, int skb_size); | |
388 | ||
389 | extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src); | |
390 | extern struct sk_buff *skb_clone(struct sk_buff *skb, | |
391 | gfp_t priority); | |
392 | extern struct sk_buff *skb_copy(const struct sk_buff *skb, | |
393 | gfp_t priority); | |
394 | extern struct sk_buff *pskb_copy(struct sk_buff *skb, | |
395 | gfp_t gfp_mask); | |
396 | extern int pskb_expand_head(struct sk_buff *skb, | |
397 | int nhead, int ntail, | |
398 | gfp_t gfp_mask); | |
399 | extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, | |
400 | unsigned int headroom); | |
401 | extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb, | |
402 | int newheadroom, int newtailroom, | |
403 | gfp_t priority); | |
404 | extern int skb_to_sgvec(struct sk_buff *skb, | |
405 | struct scatterlist *sg, int offset, | |
406 | int len); | |
407 | extern int skb_cow_data(struct sk_buff *skb, int tailbits, | |
408 | struct sk_buff **trailer); | |
409 | extern int skb_pad(struct sk_buff *skb, int pad); | |
410 | #define dev_kfree_skb(a) kfree_skb(a) | |
411 | extern void skb_over_panic(struct sk_buff *skb, int len, | |
412 | void *here); | |
413 | extern void skb_under_panic(struct sk_buff *skb, int len, | |
414 | void *here); | |
415 | extern void skb_truesize_bug(struct sk_buff *skb); | |
416 | ||
417 | static inline void skb_truesize_check(struct sk_buff *skb) | |
418 | { | |
419 | int len = sizeof(struct sk_buff) + skb->len; | |
420 | ||
421 | if (unlikely((int)skb->truesize < len)) | |
422 | skb_truesize_bug(skb); | |
423 | } | |
424 | ||
425 | extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, | |
426 | int getfrag(void *from, char *to, int offset, | |
427 | int len,int odd, struct sk_buff *skb), | |
428 | void *from, int length); | |
429 | ||
430 | struct skb_seq_state | |
431 | { | |
432 | __u32 lower_offset; | |
433 | __u32 upper_offset; | |
434 | __u32 frag_idx; | |
435 | __u32 stepped_offset; | |
436 | struct sk_buff *root_skb; | |
437 | struct sk_buff *cur_skb; | |
438 | __u8 *frag_data; | |
439 | }; | |
440 | ||
441 | extern void skb_prepare_seq_read(struct sk_buff *skb, | |
442 | unsigned int from, unsigned int to, | |
443 | struct skb_seq_state *st); | |
444 | extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data, | |
445 | struct skb_seq_state *st); | |
446 | extern void skb_abort_seq_read(struct skb_seq_state *st); | |
447 | ||
448 | extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, | |
449 | unsigned int to, struct ts_config *config, | |
450 | struct ts_state *state); | |
451 | ||
452 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
453 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
454 | { | |
455 | return skb->head + skb->end; | |
456 | } | |
457 | #else | |
458 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
459 | { | |
460 | return skb->end; | |
461 | } | |
462 | #endif | |
463 | ||
464 | /* Internal */ | |
465 | #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) | |
466 | ||
467 | /** | |
468 | * skb_queue_empty - check if a queue is empty | |
469 | * @list: queue head | |
470 | * | |
471 | * Returns true if the queue is empty, false otherwise. | |
472 | */ | |
473 | static inline int skb_queue_empty(const struct sk_buff_head *list) | |
474 | { | |
475 | return list->next == (struct sk_buff *)list; | |
476 | } | |
477 | ||
478 | /** | |
479 | * skb_queue_is_last - check if skb is the last entry in the queue | |
480 | * @list: queue head | |
481 | * @skb: buffer | |
482 | * | |
483 | * Returns true if @skb is the last buffer on the list. | |
484 | */ | |
485 | static inline bool skb_queue_is_last(const struct sk_buff_head *list, | |
486 | const struct sk_buff *skb) | |
487 | { | |
488 | return (skb->next == (struct sk_buff *) list); | |
489 | } | |
490 | ||
491 | /** | |
492 | * skb_queue_next - return the next packet in the queue | |
493 | * @list: queue head | |
494 | * @skb: current buffer | |
495 | * | |
496 | * Return the next packet in @list after @skb. It is only valid to | |
497 | * call this if skb_queue_is_last() evaluates to false. | |
498 | */ | |
499 | static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list, | |
500 | const struct sk_buff *skb) | |
501 | { | |
502 | /* This BUG_ON may seem severe, but if we just return then we | |
503 | * are going to dereference garbage. | |
504 | */ | |
505 | BUG_ON(skb_queue_is_last(list, skb)); | |
506 | return skb->next; | |
507 | } | |
508 | ||
509 | /** | |
510 | * skb_get - reference buffer | |
511 | * @skb: buffer to reference | |
512 | * | |
513 | * Makes another reference to a socket buffer and returns a pointer | |
514 | * to the buffer. | |
515 | */ | |
516 | static inline struct sk_buff *skb_get(struct sk_buff *skb) | |
517 | { | |
518 | atomic_inc(&skb->users); | |
519 | return skb; | |
520 | } | |
521 | ||
522 | /* | |
523 | * If users == 1, we are the only owner and are can avoid redundant | |
524 | * atomic change. | |
525 | */ | |
526 | ||
527 | /** | |
528 | * skb_cloned - is the buffer a clone | |
529 | * @skb: buffer to check | |
530 | * | |
531 | * Returns true if the buffer was generated with skb_clone() and is | |
532 | * one of multiple shared copies of the buffer. Cloned buffers are | |
533 | * shared data so must not be written to under normal circumstances. | |
534 | */ | |
535 | static inline int skb_cloned(const struct sk_buff *skb) | |
536 | { | |
537 | return skb->cloned && | |
538 | (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; | |
539 | } | |
540 | ||
541 | /** | |
542 | * skb_header_cloned - is the header a clone | |
543 | * @skb: buffer to check | |
544 | * | |
545 | * Returns true if modifying the header part of the buffer requires | |
546 | * the data to be copied. | |
547 | */ | |
548 | static inline int skb_header_cloned(const struct sk_buff *skb) | |
549 | { | |
550 | int dataref; | |
551 | ||
552 | if (!skb->cloned) | |
553 | return 0; | |
554 | ||
555 | dataref = atomic_read(&skb_shinfo(skb)->dataref); | |
556 | dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); | |
557 | return dataref != 1; | |
558 | } | |
559 | ||
560 | /** | |
561 | * skb_header_release - release reference to header | |
562 | * @skb: buffer to operate on | |
563 | * | |
564 | * Drop a reference to the header part of the buffer. This is done | |
565 | * by acquiring a payload reference. You must not read from the header | |
566 | * part of skb->data after this. | |
567 | */ | |
568 | static inline void skb_header_release(struct sk_buff *skb) | |
569 | { | |
570 | BUG_ON(skb->nohdr); | |
571 | skb->nohdr = 1; | |
572 | atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); | |
573 | } | |
574 | ||
575 | /** | |
576 | * skb_shared - is the buffer shared | |
577 | * @skb: buffer to check | |
578 | * | |
579 | * Returns true if more than one person has a reference to this | |
580 | * buffer. | |
581 | */ | |
582 | static inline int skb_shared(const struct sk_buff *skb) | |
583 | { | |
584 | return atomic_read(&skb->users) != 1; | |
585 | } | |
586 | ||
587 | /** | |
588 | * skb_share_check - check if buffer is shared and if so clone it | |
589 | * @skb: buffer to check | |
590 | * @pri: priority for memory allocation | |
591 | * | |
592 | * If the buffer is shared the buffer is cloned and the old copy | |
593 | * drops a reference. A new clone with a single reference is returned. | |
594 | * If the buffer is not shared the original buffer is returned. When | |
595 | * being called from interrupt status or with spinlocks held pri must | |
596 | * be GFP_ATOMIC. | |
597 | * | |
598 | * NULL is returned on a memory allocation failure. | |
599 | */ | |
600 | static inline struct sk_buff *skb_share_check(struct sk_buff *skb, | |
601 | gfp_t pri) | |
602 | { | |
603 | might_sleep_if(pri & __GFP_WAIT); | |
604 | if (skb_shared(skb)) { | |
605 | struct sk_buff *nskb = skb_clone(skb, pri); | |
606 | kfree_skb(skb); | |
607 | skb = nskb; | |
608 | } | |
609 | return skb; | |
610 | } | |
611 | ||
612 | /* | |
613 | * Copy shared buffers into a new sk_buff. We effectively do COW on | |
614 | * packets to handle cases where we have a local reader and forward | |
615 | * and a couple of other messy ones. The normal one is tcpdumping | |
616 | * a packet thats being forwarded. | |
617 | */ | |
618 | ||
619 | /** | |
620 | * skb_unshare - make a copy of a shared buffer | |
621 | * @skb: buffer to check | |
622 | * @pri: priority for memory allocation | |
623 | * | |
624 | * If the socket buffer is a clone then this function creates a new | |
625 | * copy of the data, drops a reference count on the old copy and returns | |
626 | * the new copy with the reference count at 1. If the buffer is not a clone | |
627 | * the original buffer is returned. When called with a spinlock held or | |
628 | * from interrupt state @pri must be %GFP_ATOMIC | |
629 | * | |
630 | * %NULL is returned on a memory allocation failure. | |
631 | */ | |
632 | static inline struct sk_buff *skb_unshare(struct sk_buff *skb, | |
633 | gfp_t pri) | |
634 | { | |
635 | might_sleep_if(pri & __GFP_WAIT); | |
636 | if (skb_cloned(skb)) { | |
637 | struct sk_buff *nskb = skb_copy(skb, pri); | |
638 | kfree_skb(skb); /* Free our shared copy */ | |
639 | skb = nskb; | |
640 | } | |
641 | return skb; | |
642 | } | |
643 | ||
644 | /** | |
645 | * skb_peek | |
646 | * @list_: list to peek at | |
647 | * | |
648 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
649 | * be careful with this one. A peek leaves the buffer on the | |
650 | * list and someone else may run off with it. You must hold | |
651 | * the appropriate locks or have a private queue to do this. | |
652 | * | |
653 | * Returns %NULL for an empty list or a pointer to the head element. | |
654 | * The reference count is not incremented and the reference is therefore | |
655 | * volatile. Use with caution. | |
656 | */ | |
657 | static inline struct sk_buff *skb_peek(struct sk_buff_head *list_) | |
658 | { | |
659 | struct sk_buff *list = ((struct sk_buff *)list_)->next; | |
660 | if (list == (struct sk_buff *)list_) | |
661 | list = NULL; | |
662 | return list; | |
663 | } | |
664 | ||
665 | /** | |
666 | * skb_peek_tail | |
667 | * @list_: list to peek at | |
668 | * | |
669 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
670 | * be careful with this one. A peek leaves the buffer on the | |
671 | * list and someone else may run off with it. You must hold | |
672 | * the appropriate locks or have a private queue to do this. | |
673 | * | |
674 | * Returns %NULL for an empty list or a pointer to the tail element. | |
675 | * The reference count is not incremented and the reference is therefore | |
676 | * volatile. Use with caution. | |
677 | */ | |
678 | static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_) | |
679 | { | |
680 | struct sk_buff *list = ((struct sk_buff *)list_)->prev; | |
681 | if (list == (struct sk_buff *)list_) | |
682 | list = NULL; | |
683 | return list; | |
684 | } | |
685 | ||
686 | /** | |
687 | * skb_queue_len - get queue length | |
688 | * @list_: list to measure | |
689 | * | |
690 | * Return the length of an &sk_buff queue. | |
691 | */ | |
692 | static inline __u32 skb_queue_len(const struct sk_buff_head *list_) | |
693 | { | |
694 | return list_->qlen; | |
695 | } | |
696 | ||
697 | /** | |
698 | * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head | |
699 | * @list: queue to initialize | |
700 | * | |
701 | * This initializes only the list and queue length aspects of | |
702 | * an sk_buff_head object. This allows to initialize the list | |
703 | * aspects of an sk_buff_head without reinitializing things like | |
704 | * the spinlock. It can also be used for on-stack sk_buff_head | |
705 | * objects where the spinlock is known to not be used. | |
706 | */ | |
707 | static inline void __skb_queue_head_init(struct sk_buff_head *list) | |
708 | { | |
709 | list->prev = list->next = (struct sk_buff *)list; | |
710 | list->qlen = 0; | |
711 | } | |
712 | ||
713 | /* | |
714 | * This function creates a split out lock class for each invocation; | |
715 | * this is needed for now since a whole lot of users of the skb-queue | |
716 | * infrastructure in drivers have different locking usage (in hardirq) | |
717 | * than the networking core (in softirq only). In the long run either the | |
718 | * network layer or drivers should need annotation to consolidate the | |
719 | * main types of usage into 3 classes. | |
720 | */ | |
721 | static inline void skb_queue_head_init(struct sk_buff_head *list) | |
722 | { | |
723 | spin_lock_init(&list->lock); | |
724 | __skb_queue_head_init(list); | |
725 | } | |
726 | ||
727 | static inline void skb_queue_head_init_class(struct sk_buff_head *list, | |
728 | struct lock_class_key *class) | |
729 | { | |
730 | skb_queue_head_init(list); | |
731 | lockdep_set_class(&list->lock, class); | |
732 | } | |
733 | ||
734 | /* | |
735 | * Insert an sk_buff on a list. | |
736 | * | |
737 | * The "__skb_xxxx()" functions are the non-atomic ones that | |
738 | * can only be called with interrupts disabled. | |
739 | */ | |
740 | extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); | |
741 | static inline void __skb_insert(struct sk_buff *newsk, | |
742 | struct sk_buff *prev, struct sk_buff *next, | |
743 | struct sk_buff_head *list) | |
744 | { | |
745 | newsk->next = next; | |
746 | newsk->prev = prev; | |
747 | next->prev = prev->next = newsk; | |
748 | list->qlen++; | |
749 | } | |
750 | ||
751 | static inline void __skb_queue_splice(const struct sk_buff_head *list, | |
752 | struct sk_buff *prev, | |
753 | struct sk_buff *next) | |
754 | { | |
755 | struct sk_buff *first = list->next; | |
756 | struct sk_buff *last = list->prev; | |
757 | ||
758 | first->prev = prev; | |
759 | prev->next = first; | |
760 | ||
761 | last->next = next; | |
762 | next->prev = last; | |
763 | } | |
764 | ||
765 | /** | |
766 | * skb_queue_splice - join two skb lists, this is designed for stacks | |
767 | * @list: the new list to add | |
768 | * @head: the place to add it in the first list | |
769 | */ | |
770 | static inline void skb_queue_splice(const struct sk_buff_head *list, | |
771 | struct sk_buff_head *head) | |
772 | { | |
773 | if (!skb_queue_empty(list)) { | |
774 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
775 | head->qlen += list->qlen; | |
776 | } | |
777 | } | |
778 | ||
779 | /** | |
780 | * skb_queue_splice - join two skb lists and reinitialise the emptied list | |
781 | * @list: the new list to add | |
782 | * @head: the place to add it in the first list | |
783 | * | |
784 | * The list at @list is reinitialised | |
785 | */ | |
786 | static inline void skb_queue_splice_init(struct sk_buff_head *list, | |
787 | struct sk_buff_head *head) | |
788 | { | |
789 | if (!skb_queue_empty(list)) { | |
790 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
791 | head->qlen += list->qlen; | |
792 | __skb_queue_head_init(list); | |
793 | } | |
794 | } | |
795 | ||
796 | /** | |
797 | * skb_queue_splice_tail - join two skb lists, each list being a queue | |
798 | * @list: the new list to add | |
799 | * @head: the place to add it in the first list | |
800 | */ | |
801 | static inline void skb_queue_splice_tail(const struct sk_buff_head *list, | |
802 | struct sk_buff_head *head) | |
803 | { | |
804 | if (!skb_queue_empty(list)) { | |
805 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
806 | head->qlen += list->qlen; | |
807 | } | |
808 | } | |
809 | ||
810 | /** | |
811 | * skb_queue_splice_tail - join two skb lists and reinitialise the emptied list | |
812 | * @list: the new list to add | |
813 | * @head: the place to add it in the first list | |
814 | * | |
815 | * Each of the lists is a queue. | |
816 | * The list at @list is reinitialised | |
817 | */ | |
818 | static inline void skb_queue_splice_tail_init(struct sk_buff_head *list, | |
819 | struct sk_buff_head *head) | |
820 | { | |
821 | if (!skb_queue_empty(list)) { | |
822 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
823 | head->qlen += list->qlen; | |
824 | __skb_queue_head_init(list); | |
825 | } | |
826 | } | |
827 | ||
828 | /** | |
829 | * __skb_queue_after - queue a buffer at the list head | |
830 | * @list: list to use | |
831 | * @prev: place after this buffer | |
832 | * @newsk: buffer to queue | |
833 | * | |
834 | * Queue a buffer int the middle of a list. This function takes no locks | |
835 | * and you must therefore hold required locks before calling it. | |
836 | * | |
837 | * A buffer cannot be placed on two lists at the same time. | |
838 | */ | |
839 | static inline void __skb_queue_after(struct sk_buff_head *list, | |
840 | struct sk_buff *prev, | |
841 | struct sk_buff *newsk) | |
842 | { | |
843 | __skb_insert(newsk, prev, prev->next, list); | |
844 | } | |
845 | ||
846 | extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, | |
847 | struct sk_buff_head *list); | |
848 | ||
849 | static inline void __skb_queue_before(struct sk_buff_head *list, | |
850 | struct sk_buff *next, | |
851 | struct sk_buff *newsk) | |
852 | { | |
853 | __skb_insert(newsk, next->prev, next, list); | |
854 | } | |
855 | ||
856 | /** | |
857 | * __skb_queue_head - queue a buffer at the list head | |
858 | * @list: list to use | |
859 | * @newsk: buffer to queue | |
860 | * | |
861 | * Queue a buffer at the start of a list. This function takes no locks | |
862 | * and you must therefore hold required locks before calling it. | |
863 | * | |
864 | * A buffer cannot be placed on two lists at the same time. | |
865 | */ | |
866 | extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); | |
867 | static inline void __skb_queue_head(struct sk_buff_head *list, | |
868 | struct sk_buff *newsk) | |
869 | { | |
870 | __skb_queue_after(list, (struct sk_buff *)list, newsk); | |
871 | } | |
872 | ||
873 | /** | |
874 | * __skb_queue_tail - queue a buffer at the list tail | |
875 | * @list: list to use | |
876 | * @newsk: buffer to queue | |
877 | * | |
878 | * Queue a buffer at the end of a list. This function takes no locks | |
879 | * and you must therefore hold required locks before calling it. | |
880 | * | |
881 | * A buffer cannot be placed on two lists at the same time. | |
882 | */ | |
883 | extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); | |
884 | static inline void __skb_queue_tail(struct sk_buff_head *list, | |
885 | struct sk_buff *newsk) | |
886 | { | |
887 | __skb_queue_before(list, (struct sk_buff *)list, newsk); | |
888 | } | |
889 | ||
890 | /* | |
891 | * remove sk_buff from list. _Must_ be called atomically, and with | |
892 | * the list known.. | |
893 | */ | |
894 | extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); | |
895 | static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) | |
896 | { | |
897 | struct sk_buff *next, *prev; | |
898 | ||
899 | list->qlen--; | |
900 | next = skb->next; | |
901 | prev = skb->prev; | |
902 | skb->next = skb->prev = NULL; | |
903 | next->prev = prev; | |
904 | prev->next = next; | |
905 | } | |
906 | ||
907 | /** | |
908 | * __skb_dequeue - remove from the head of the queue | |
909 | * @list: list to dequeue from | |
910 | * | |
911 | * Remove the head of the list. This function does not take any locks | |
912 | * so must be used with appropriate locks held only. The head item is | |
913 | * returned or %NULL if the list is empty. | |
914 | */ | |
915 | extern struct sk_buff *skb_dequeue(struct sk_buff_head *list); | |
916 | static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) | |
917 | { | |
918 | struct sk_buff *skb = skb_peek(list); | |
919 | if (skb) | |
920 | __skb_unlink(skb, list); | |
921 | return skb; | |
922 | } | |
923 | ||
924 | /** | |
925 | * __skb_dequeue_tail - remove from the tail of the queue | |
926 | * @list: list to dequeue from | |
927 | * | |
928 | * Remove the tail of the list. This function does not take any locks | |
929 | * so must be used with appropriate locks held only. The tail item is | |
930 | * returned or %NULL if the list is empty. | |
931 | */ | |
932 | extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); | |
933 | static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) | |
934 | { | |
935 | struct sk_buff *skb = skb_peek_tail(list); | |
936 | if (skb) | |
937 | __skb_unlink(skb, list); | |
938 | return skb; | |
939 | } | |
940 | ||
941 | ||
942 | static inline int skb_is_nonlinear(const struct sk_buff *skb) | |
943 | { | |
944 | return skb->data_len; | |
945 | } | |
946 | ||
947 | static inline unsigned int skb_headlen(const struct sk_buff *skb) | |
948 | { | |
949 | return skb->len - skb->data_len; | |
950 | } | |
951 | ||
952 | static inline int skb_pagelen(const struct sk_buff *skb) | |
953 | { | |
954 | int i, len = 0; | |
955 | ||
956 | for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) | |
957 | len += skb_shinfo(skb)->frags[i].size; | |
958 | return len + skb_headlen(skb); | |
959 | } | |
960 | ||
961 | static inline void skb_fill_page_desc(struct sk_buff *skb, int i, | |
962 | struct page *page, int off, int size) | |
963 | { | |
964 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; | |
965 | ||
966 | frag->page = page; | |
967 | frag->page_offset = off; | |
968 | frag->size = size; | |
969 | skb_shinfo(skb)->nr_frags = i + 1; | |
970 | } | |
971 | ||
972 | extern void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, | |
973 | int off, int size); | |
974 | ||
975 | #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) | |
976 | #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list) | |
977 | #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) | |
978 | ||
979 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
980 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
981 | { | |
982 | return skb->head + skb->tail; | |
983 | } | |
984 | ||
985 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
986 | { | |
987 | skb->tail = skb->data - skb->head; | |
988 | } | |
989 | ||
990 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
991 | { | |
992 | skb_reset_tail_pointer(skb); | |
993 | skb->tail += offset; | |
994 | } | |
995 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ | |
996 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
997 | { | |
998 | return skb->tail; | |
999 | } | |
1000 | ||
1001 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
1002 | { | |
1003 | skb->tail = skb->data; | |
1004 | } | |
1005 | ||
1006 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
1007 | { | |
1008 | skb->tail = skb->data + offset; | |
1009 | } | |
1010 | ||
1011 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ | |
1012 | ||
1013 | /* | |
1014 | * Add data to an sk_buff | |
1015 | */ | |
1016 | extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len); | |
1017 | static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) | |
1018 | { | |
1019 | unsigned char *tmp = skb_tail_pointer(skb); | |
1020 | SKB_LINEAR_ASSERT(skb); | |
1021 | skb->tail += len; | |
1022 | skb->len += len; | |
1023 | return tmp; | |
1024 | } | |
1025 | ||
1026 | extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len); | |
1027 | static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) | |
1028 | { | |
1029 | skb->data -= len; | |
1030 | skb->len += len; | |
1031 | return skb->data; | |
1032 | } | |
1033 | ||
1034 | extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len); | |
1035 | static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) | |
1036 | { | |
1037 | skb->len -= len; | |
1038 | BUG_ON(skb->len < skb->data_len); | |
1039 | return skb->data += len; | |
1040 | } | |
1041 | ||
1042 | extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); | |
1043 | ||
1044 | static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) | |
1045 | { | |
1046 | if (len > skb_headlen(skb) && | |
1047 | !__pskb_pull_tail(skb, len - skb_headlen(skb))) | |
1048 | return NULL; | |
1049 | skb->len -= len; | |
1050 | return skb->data += len; | |
1051 | } | |
1052 | ||
1053 | static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) | |
1054 | { | |
1055 | return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); | |
1056 | } | |
1057 | ||
1058 | static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) | |
1059 | { | |
1060 | if (likely(len <= skb_headlen(skb))) | |
1061 | return 1; | |
1062 | if (unlikely(len > skb->len)) | |
1063 | return 0; | |
1064 | return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL; | |
1065 | } | |
1066 | ||
1067 | /** | |
1068 | * skb_headroom - bytes at buffer head | |
1069 | * @skb: buffer to check | |
1070 | * | |
1071 | * Return the number of bytes of free space at the head of an &sk_buff. | |
1072 | */ | |
1073 | static inline unsigned int skb_headroom(const struct sk_buff *skb) | |
1074 | { | |
1075 | return skb->data - skb->head; | |
1076 | } | |
1077 | ||
1078 | /** | |
1079 | * skb_tailroom - bytes at buffer end | |
1080 | * @skb: buffer to check | |
1081 | * | |
1082 | * Return the number of bytes of free space at the tail of an sk_buff | |
1083 | */ | |
1084 | static inline int skb_tailroom(const struct sk_buff *skb) | |
1085 | { | |
1086 | return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; | |
1087 | } | |
1088 | ||
1089 | /** | |
1090 | * skb_reserve - adjust headroom | |
1091 | * @skb: buffer to alter | |
1092 | * @len: bytes to move | |
1093 | * | |
1094 | * Increase the headroom of an empty &sk_buff by reducing the tail | |
1095 | * room. This is only allowed for an empty buffer. | |
1096 | */ | |
1097 | static inline void skb_reserve(struct sk_buff *skb, int len) | |
1098 | { | |
1099 | skb->data += len; | |
1100 | skb->tail += len; | |
1101 | } | |
1102 | ||
1103 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
1104 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) | |
1105 | { | |
1106 | return skb->head + skb->transport_header; | |
1107 | } | |
1108 | ||
1109 | static inline void skb_reset_transport_header(struct sk_buff *skb) | |
1110 | { | |
1111 | skb->transport_header = skb->data - skb->head; | |
1112 | } | |
1113 | ||
1114 | static inline void skb_set_transport_header(struct sk_buff *skb, | |
1115 | const int offset) | |
1116 | { | |
1117 | skb_reset_transport_header(skb); | |
1118 | skb->transport_header += offset; | |
1119 | } | |
1120 | ||
1121 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) | |
1122 | { | |
1123 | return skb->head + skb->network_header; | |
1124 | } | |
1125 | ||
1126 | static inline void skb_reset_network_header(struct sk_buff *skb) | |
1127 | { | |
1128 | skb->network_header = skb->data - skb->head; | |
1129 | } | |
1130 | ||
1131 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) | |
1132 | { | |
1133 | skb_reset_network_header(skb); | |
1134 | skb->network_header += offset; | |
1135 | } | |
1136 | ||
1137 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) | |
1138 | { | |
1139 | return skb->head + skb->mac_header; | |
1140 | } | |
1141 | ||
1142 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) | |
1143 | { | |
1144 | return skb->mac_header != ~0U; | |
1145 | } | |
1146 | ||
1147 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1148 | { | |
1149 | skb->mac_header = skb->data - skb->head; | |
1150 | } | |
1151 | ||
1152 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1153 | { | |
1154 | skb_reset_mac_header(skb); | |
1155 | skb->mac_header += offset; | |
1156 | } | |
1157 | ||
1158 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ | |
1159 | ||
1160 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) | |
1161 | { | |
1162 | return skb->transport_header; | |
1163 | } | |
1164 | ||
1165 | static inline void skb_reset_transport_header(struct sk_buff *skb) | |
1166 | { | |
1167 | skb->transport_header = skb->data; | |
1168 | } | |
1169 | ||
1170 | static inline void skb_set_transport_header(struct sk_buff *skb, | |
1171 | const int offset) | |
1172 | { | |
1173 | skb->transport_header = skb->data + offset; | |
1174 | } | |
1175 | ||
1176 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) | |
1177 | { | |
1178 | return skb->network_header; | |
1179 | } | |
1180 | ||
1181 | static inline void skb_reset_network_header(struct sk_buff *skb) | |
1182 | { | |
1183 | skb->network_header = skb->data; | |
1184 | } | |
1185 | ||
1186 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) | |
1187 | { | |
1188 | skb->network_header = skb->data + offset; | |
1189 | } | |
1190 | ||
1191 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) | |
1192 | { | |
1193 | return skb->mac_header; | |
1194 | } | |
1195 | ||
1196 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) | |
1197 | { | |
1198 | return skb->mac_header != NULL; | |
1199 | } | |
1200 | ||
1201 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1202 | { | |
1203 | skb->mac_header = skb->data; | |
1204 | } | |
1205 | ||
1206 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1207 | { | |
1208 | skb->mac_header = skb->data + offset; | |
1209 | } | |
1210 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ | |
1211 | ||
1212 | static inline int skb_transport_offset(const struct sk_buff *skb) | |
1213 | { | |
1214 | return skb_transport_header(skb) - skb->data; | |
1215 | } | |
1216 | ||
1217 | static inline u32 skb_network_header_len(const struct sk_buff *skb) | |
1218 | { | |
1219 | return skb->transport_header - skb->network_header; | |
1220 | } | |
1221 | ||
1222 | static inline int skb_network_offset(const struct sk_buff *skb) | |
1223 | { | |
1224 | return skb_network_header(skb) - skb->data; | |
1225 | } | |
1226 | ||
1227 | /* | |
1228 | * CPUs often take a performance hit when accessing unaligned memory | |
1229 | * locations. The actual performance hit varies, it can be small if the | |
1230 | * hardware handles it or large if we have to take an exception and fix it | |
1231 | * in software. | |
1232 | * | |
1233 | * Since an ethernet header is 14 bytes network drivers often end up with | |
1234 | * the IP header at an unaligned offset. The IP header can be aligned by | |
1235 | * shifting the start of the packet by 2 bytes. Drivers should do this | |
1236 | * with: | |
1237 | * | |
1238 | * skb_reserve(NET_IP_ALIGN); | |
1239 | * | |
1240 | * The downside to this alignment of the IP header is that the DMA is now | |
1241 | * unaligned. On some architectures the cost of an unaligned DMA is high | |
1242 | * and this cost outweighs the gains made by aligning the IP header. | |
1243 | * | |
1244 | * Since this trade off varies between architectures, we allow NET_IP_ALIGN | |
1245 | * to be overridden. | |
1246 | */ | |
1247 | #ifndef NET_IP_ALIGN | |
1248 | #define NET_IP_ALIGN 2 | |
1249 | #endif | |
1250 | ||
1251 | /* | |
1252 | * The networking layer reserves some headroom in skb data (via | |
1253 | * dev_alloc_skb). This is used to avoid having to reallocate skb data when | |
1254 | * the header has to grow. In the default case, if the header has to grow | |
1255 | * 16 bytes or less we avoid the reallocation. | |
1256 | * | |
1257 | * Unfortunately this headroom changes the DMA alignment of the resulting | |
1258 | * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive | |
1259 | * on some architectures. An architecture can override this value, | |
1260 | * perhaps setting it to a cacheline in size (since that will maintain | |
1261 | * cacheline alignment of the DMA). It must be a power of 2. | |
1262 | * | |
1263 | * Various parts of the networking layer expect at least 16 bytes of | |
1264 | * headroom, you should not reduce this. | |
1265 | */ | |
1266 | #ifndef NET_SKB_PAD | |
1267 | #define NET_SKB_PAD 16 | |
1268 | #endif | |
1269 | ||
1270 | extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); | |
1271 | ||
1272 | static inline void __skb_trim(struct sk_buff *skb, unsigned int len) | |
1273 | { | |
1274 | if (unlikely(skb->data_len)) { | |
1275 | WARN_ON(1); | |
1276 | return; | |
1277 | } | |
1278 | skb->len = len; | |
1279 | skb_set_tail_pointer(skb, len); | |
1280 | } | |
1281 | ||
1282 | extern void skb_trim(struct sk_buff *skb, unsigned int len); | |
1283 | ||
1284 | static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) | |
1285 | { | |
1286 | if (skb->data_len) | |
1287 | return ___pskb_trim(skb, len); | |
1288 | __skb_trim(skb, len); | |
1289 | return 0; | |
1290 | } | |
1291 | ||
1292 | static inline int pskb_trim(struct sk_buff *skb, unsigned int len) | |
1293 | { | |
1294 | return (len < skb->len) ? __pskb_trim(skb, len) : 0; | |
1295 | } | |
1296 | ||
1297 | /** | |
1298 | * pskb_trim_unique - remove end from a paged unique (not cloned) buffer | |
1299 | * @skb: buffer to alter | |
1300 | * @len: new length | |
1301 | * | |
1302 | * This is identical to pskb_trim except that the caller knows that | |
1303 | * the skb is not cloned so we should never get an error due to out- | |
1304 | * of-memory. | |
1305 | */ | |
1306 | static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) | |
1307 | { | |
1308 | int err = pskb_trim(skb, len); | |
1309 | BUG_ON(err); | |
1310 | } | |
1311 | ||
1312 | /** | |
1313 | * skb_orphan - orphan a buffer | |
1314 | * @skb: buffer to orphan | |
1315 | * | |
1316 | * If a buffer currently has an owner then we call the owner's | |
1317 | * destructor function and make the @skb unowned. The buffer continues | |
1318 | * to exist but is no longer charged to its former owner. | |
1319 | */ | |
1320 | static inline void skb_orphan(struct sk_buff *skb) | |
1321 | { | |
1322 | if (skb->destructor) | |
1323 | skb->destructor(skb); | |
1324 | skb->destructor = NULL; | |
1325 | skb->sk = NULL; | |
1326 | } | |
1327 | ||
1328 | /** | |
1329 | * __skb_queue_purge - empty a list | |
1330 | * @list: list to empty | |
1331 | * | |
1332 | * Delete all buffers on an &sk_buff list. Each buffer is removed from | |
1333 | * the list and one reference dropped. This function does not take the | |
1334 | * list lock and the caller must hold the relevant locks to use it. | |
1335 | */ | |
1336 | extern void skb_queue_purge(struct sk_buff_head *list); | |
1337 | static inline void __skb_queue_purge(struct sk_buff_head *list) | |
1338 | { | |
1339 | struct sk_buff *skb; | |
1340 | while ((skb = __skb_dequeue(list)) != NULL) | |
1341 | kfree_skb(skb); | |
1342 | } | |
1343 | ||
1344 | /** | |
1345 | * __dev_alloc_skb - allocate an skbuff for receiving | |
1346 | * @length: length to allocate | |
1347 | * @gfp_mask: get_free_pages mask, passed to alloc_skb | |
1348 | * | |
1349 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
1350 | * buffer has unspecified headroom built in. Users should allocate | |
1351 | * the headroom they think they need without accounting for the | |
1352 | * built in space. The built in space is used for optimisations. | |
1353 | * | |
1354 | * %NULL is returned if there is no free memory. | |
1355 | */ | |
1356 | static inline struct sk_buff *__dev_alloc_skb(unsigned int length, | |
1357 | gfp_t gfp_mask) | |
1358 | { | |
1359 | struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); | |
1360 | if (likely(skb)) | |
1361 | skb_reserve(skb, NET_SKB_PAD); | |
1362 | return skb; | |
1363 | } | |
1364 | ||
1365 | extern struct sk_buff *dev_alloc_skb(unsigned int length); | |
1366 | ||
1367 | extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev, | |
1368 | unsigned int length, gfp_t gfp_mask); | |
1369 | ||
1370 | /** | |
1371 | * netdev_alloc_skb - allocate an skbuff for rx on a specific device | |
1372 | * @dev: network device to receive on | |
1373 | * @length: length to allocate | |
1374 | * | |
1375 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
1376 | * buffer has unspecified headroom built in. Users should allocate | |
1377 | * the headroom they think they need without accounting for the | |
1378 | * built in space. The built in space is used for optimisations. | |
1379 | * | |
1380 | * %NULL is returned if there is no free memory. Although this function | |
1381 | * allocates memory it can be called from an interrupt. | |
1382 | */ | |
1383 | static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, | |
1384 | unsigned int length) | |
1385 | { | |
1386 | return __netdev_alloc_skb(dev, length, GFP_ATOMIC); | |
1387 | } | |
1388 | ||
1389 | extern struct page *__netdev_alloc_page(struct net_device *dev, gfp_t gfp_mask); | |
1390 | ||
1391 | /** | |
1392 | * netdev_alloc_page - allocate a page for ps-rx on a specific device | |
1393 | * @dev: network device to receive on | |
1394 | * | |
1395 | * Allocate a new page node local to the specified device. | |
1396 | * | |
1397 | * %NULL is returned if there is no free memory. | |
1398 | */ | |
1399 | static inline struct page *netdev_alloc_page(struct net_device *dev) | |
1400 | { | |
1401 | return __netdev_alloc_page(dev, GFP_ATOMIC); | |
1402 | } | |
1403 | ||
1404 | static inline void netdev_free_page(struct net_device *dev, struct page *page) | |
1405 | { | |
1406 | __free_page(page); | |
1407 | } | |
1408 | ||
1409 | /** | |
1410 | * skb_clone_writable - is the header of a clone writable | |
1411 | * @skb: buffer to check | |
1412 | * @len: length up to which to write | |
1413 | * | |
1414 | * Returns true if modifying the header part of the cloned buffer | |
1415 | * does not requires the data to be copied. | |
1416 | */ | |
1417 | static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len) | |
1418 | { | |
1419 | return !skb_header_cloned(skb) && | |
1420 | skb_headroom(skb) + len <= skb->hdr_len; | |
1421 | } | |
1422 | ||
1423 | static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom, | |
1424 | int cloned) | |
1425 | { | |
1426 | int delta = 0; | |
1427 | ||
1428 | if (headroom < NET_SKB_PAD) | |
1429 | headroom = NET_SKB_PAD; | |
1430 | if (headroom > skb_headroom(skb)) | |
1431 | delta = headroom - skb_headroom(skb); | |
1432 | ||
1433 | if (delta || cloned) | |
1434 | return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, | |
1435 | GFP_ATOMIC); | |
1436 | return 0; | |
1437 | } | |
1438 | ||
1439 | /** | |
1440 | * skb_cow - copy header of skb when it is required | |
1441 | * @skb: buffer to cow | |
1442 | * @headroom: needed headroom | |
1443 | * | |
1444 | * If the skb passed lacks sufficient headroom or its data part | |
1445 | * is shared, data is reallocated. If reallocation fails, an error | |
1446 | * is returned and original skb is not changed. | |
1447 | * | |
1448 | * The result is skb with writable area skb->head...skb->tail | |
1449 | * and at least @headroom of space at head. | |
1450 | */ | |
1451 | static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) | |
1452 | { | |
1453 | return __skb_cow(skb, headroom, skb_cloned(skb)); | |
1454 | } | |
1455 | ||
1456 | /** | |
1457 | * skb_cow_head - skb_cow but only making the head writable | |
1458 | * @skb: buffer to cow | |
1459 | * @headroom: needed headroom | |
1460 | * | |
1461 | * This function is identical to skb_cow except that we replace the | |
1462 | * skb_cloned check by skb_header_cloned. It should be used when | |
1463 | * you only need to push on some header and do not need to modify | |
1464 | * the data. | |
1465 | */ | |
1466 | static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom) | |
1467 | { | |
1468 | return __skb_cow(skb, headroom, skb_header_cloned(skb)); | |
1469 | } | |
1470 | ||
1471 | /** | |
1472 | * skb_padto - pad an skbuff up to a minimal size | |
1473 | * @skb: buffer to pad | |
1474 | * @len: minimal length | |
1475 | * | |
1476 | * Pads up a buffer to ensure the trailing bytes exist and are | |
1477 | * blanked. If the buffer already contains sufficient data it | |
1478 | * is untouched. Otherwise it is extended. Returns zero on | |
1479 | * success. The skb is freed on error. | |
1480 | */ | |
1481 | ||
1482 | static inline int skb_padto(struct sk_buff *skb, unsigned int len) | |
1483 | { | |
1484 | unsigned int size = skb->len; | |
1485 | if (likely(size >= len)) | |
1486 | return 0; | |
1487 | return skb_pad(skb, len - size); | |
1488 | } | |
1489 | ||
1490 | static inline int skb_add_data(struct sk_buff *skb, | |
1491 | char __user *from, int copy) | |
1492 | { | |
1493 | const int off = skb->len; | |
1494 | ||
1495 | if (skb->ip_summed == CHECKSUM_NONE) { | |
1496 | int err = 0; | |
1497 | __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), | |
1498 | copy, 0, &err); | |
1499 | if (!err) { | |
1500 | skb->csum = csum_block_add(skb->csum, csum, off); | |
1501 | return 0; | |
1502 | } | |
1503 | } else if (!copy_from_user(skb_put(skb, copy), from, copy)) | |
1504 | return 0; | |
1505 | ||
1506 | __skb_trim(skb, off); | |
1507 | return -EFAULT; | |
1508 | } | |
1509 | ||
1510 | static inline int skb_can_coalesce(struct sk_buff *skb, int i, | |
1511 | struct page *page, int off) | |
1512 | { | |
1513 | if (i) { | |
1514 | struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; | |
1515 | ||
1516 | return page == frag->page && | |
1517 | off == frag->page_offset + frag->size; | |
1518 | } | |
1519 | return 0; | |
1520 | } | |
1521 | ||
1522 | static inline int __skb_linearize(struct sk_buff *skb) | |
1523 | { | |
1524 | return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; | |
1525 | } | |
1526 | ||
1527 | /** | |
1528 | * skb_linearize - convert paged skb to linear one | |
1529 | * @skb: buffer to linarize | |
1530 | * | |
1531 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
1532 | * is returned and the old skb data released. | |
1533 | */ | |
1534 | static inline int skb_linearize(struct sk_buff *skb) | |
1535 | { | |
1536 | return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; | |
1537 | } | |
1538 | ||
1539 | /** | |
1540 | * skb_linearize_cow - make sure skb is linear and writable | |
1541 | * @skb: buffer to process | |
1542 | * | |
1543 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
1544 | * is returned and the old skb data released. | |
1545 | */ | |
1546 | static inline int skb_linearize_cow(struct sk_buff *skb) | |
1547 | { | |
1548 | return skb_is_nonlinear(skb) || skb_cloned(skb) ? | |
1549 | __skb_linearize(skb) : 0; | |
1550 | } | |
1551 | ||
1552 | /** | |
1553 | * skb_postpull_rcsum - update checksum for received skb after pull | |
1554 | * @skb: buffer to update | |
1555 | * @start: start of data before pull | |
1556 | * @len: length of data pulled | |
1557 | * | |
1558 | * After doing a pull on a received packet, you need to call this to | |
1559 | * update the CHECKSUM_COMPLETE checksum, or set ip_summed to | |
1560 | * CHECKSUM_NONE so that it can be recomputed from scratch. | |
1561 | */ | |
1562 | ||
1563 | static inline void skb_postpull_rcsum(struct sk_buff *skb, | |
1564 | const void *start, unsigned int len) | |
1565 | { | |
1566 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1567 | skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); | |
1568 | } | |
1569 | ||
1570 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); | |
1571 | ||
1572 | /** | |
1573 | * pskb_trim_rcsum - trim received skb and update checksum | |
1574 | * @skb: buffer to trim | |
1575 | * @len: new length | |
1576 | * | |
1577 | * This is exactly the same as pskb_trim except that it ensures the | |
1578 | * checksum of received packets are still valid after the operation. | |
1579 | */ | |
1580 | ||
1581 | static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) | |
1582 | { | |
1583 | if (likely(len >= skb->len)) | |
1584 | return 0; | |
1585 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1586 | skb->ip_summed = CHECKSUM_NONE; | |
1587 | return __pskb_trim(skb, len); | |
1588 | } | |
1589 | ||
1590 | #define skb_queue_walk(queue, skb) \ | |
1591 | for (skb = (queue)->next; \ | |
1592 | prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \ | |
1593 | skb = skb->next) | |
1594 | ||
1595 | #define skb_queue_walk_safe(queue, skb, tmp) \ | |
1596 | for (skb = (queue)->next, tmp = skb->next; \ | |
1597 | skb != (struct sk_buff *)(queue); \ | |
1598 | skb = tmp, tmp = skb->next) | |
1599 | ||
1600 | #define skb_queue_walk_from(queue, skb) \ | |
1601 | for (; prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \ | |
1602 | skb = skb->next) | |
1603 | ||
1604 | #define skb_queue_walk_from_safe(queue, skb, tmp) \ | |
1605 | for (tmp = skb->next; \ | |
1606 | skb != (struct sk_buff *)(queue); \ | |
1607 | skb = tmp, tmp = skb->next) | |
1608 | ||
1609 | #define skb_queue_reverse_walk(queue, skb) \ | |
1610 | for (skb = (queue)->prev; \ | |
1611 | prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \ | |
1612 | skb = skb->prev) | |
1613 | ||
1614 | ||
1615 | extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, | |
1616 | int *peeked, int *err); | |
1617 | extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, | |
1618 | int noblock, int *err); | |
1619 | extern unsigned int datagram_poll(struct file *file, struct socket *sock, | |
1620 | struct poll_table_struct *wait); | |
1621 | extern int skb_copy_datagram_iovec(const struct sk_buff *from, | |
1622 | int offset, struct iovec *to, | |
1623 | int size); | |
1624 | extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, | |
1625 | int hlen, | |
1626 | struct iovec *iov); | |
1627 | extern int skb_copy_datagram_from_iovec(struct sk_buff *skb, | |
1628 | int offset, | |
1629 | struct iovec *from, | |
1630 | int len); | |
1631 | extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb); | |
1632 | extern int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, | |
1633 | unsigned int flags); | |
1634 | extern __wsum skb_checksum(const struct sk_buff *skb, int offset, | |
1635 | int len, __wsum csum); | |
1636 | extern int skb_copy_bits(const struct sk_buff *skb, int offset, | |
1637 | void *to, int len); | |
1638 | extern int skb_store_bits(struct sk_buff *skb, int offset, | |
1639 | const void *from, int len); | |
1640 | extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, | |
1641 | int offset, u8 *to, int len, | |
1642 | __wsum csum); | |
1643 | extern int skb_splice_bits(struct sk_buff *skb, | |
1644 | unsigned int offset, | |
1645 | struct pipe_inode_info *pipe, | |
1646 | unsigned int len, | |
1647 | unsigned int flags); | |
1648 | extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); | |
1649 | extern void skb_split(struct sk_buff *skb, | |
1650 | struct sk_buff *skb1, const u32 len); | |
1651 | ||
1652 | extern struct sk_buff *skb_segment(struct sk_buff *skb, int features); | |
1653 | ||
1654 | static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, | |
1655 | int len, void *buffer) | |
1656 | { | |
1657 | int hlen = skb_headlen(skb); | |
1658 | ||
1659 | if (hlen - offset >= len) | |
1660 | return skb->data + offset; | |
1661 | ||
1662 | if (skb_copy_bits(skb, offset, buffer, len) < 0) | |
1663 | return NULL; | |
1664 | ||
1665 | return buffer; | |
1666 | } | |
1667 | ||
1668 | static inline void skb_copy_from_linear_data(const struct sk_buff *skb, | |
1669 | void *to, | |
1670 | const unsigned int len) | |
1671 | { | |
1672 | memcpy(to, skb->data, len); | |
1673 | } | |
1674 | ||
1675 | static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, | |
1676 | const int offset, void *to, | |
1677 | const unsigned int len) | |
1678 | { | |
1679 | memcpy(to, skb->data + offset, len); | |
1680 | } | |
1681 | ||
1682 | static inline void skb_copy_to_linear_data(struct sk_buff *skb, | |
1683 | const void *from, | |
1684 | const unsigned int len) | |
1685 | { | |
1686 | memcpy(skb->data, from, len); | |
1687 | } | |
1688 | ||
1689 | static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, | |
1690 | const int offset, | |
1691 | const void *from, | |
1692 | const unsigned int len) | |
1693 | { | |
1694 | memcpy(skb->data + offset, from, len); | |
1695 | } | |
1696 | ||
1697 | extern void skb_init(void); | |
1698 | ||
1699 | /** | |
1700 | * skb_get_timestamp - get timestamp from a skb | |
1701 | * @skb: skb to get stamp from | |
1702 | * @stamp: pointer to struct timeval to store stamp in | |
1703 | * | |
1704 | * Timestamps are stored in the skb as offsets to a base timestamp. | |
1705 | * This function converts the offset back to a struct timeval and stores | |
1706 | * it in stamp. | |
1707 | */ | |
1708 | static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp) | |
1709 | { | |
1710 | *stamp = ktime_to_timeval(skb->tstamp); | |
1711 | } | |
1712 | ||
1713 | static inline void __net_timestamp(struct sk_buff *skb) | |
1714 | { | |
1715 | skb->tstamp = ktime_get_real(); | |
1716 | } | |
1717 | ||
1718 | static inline ktime_t net_timedelta(ktime_t t) | |
1719 | { | |
1720 | return ktime_sub(ktime_get_real(), t); | |
1721 | } | |
1722 | ||
1723 | static inline ktime_t net_invalid_timestamp(void) | |
1724 | { | |
1725 | return ktime_set(0, 0); | |
1726 | } | |
1727 | ||
1728 | extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); | |
1729 | extern __sum16 __skb_checksum_complete(struct sk_buff *skb); | |
1730 | ||
1731 | static inline int skb_csum_unnecessary(const struct sk_buff *skb) | |
1732 | { | |
1733 | return skb->ip_summed & CHECKSUM_UNNECESSARY; | |
1734 | } | |
1735 | ||
1736 | /** | |
1737 | * skb_checksum_complete - Calculate checksum of an entire packet | |
1738 | * @skb: packet to process | |
1739 | * | |
1740 | * This function calculates the checksum over the entire packet plus | |
1741 | * the value of skb->csum. The latter can be used to supply the | |
1742 | * checksum of a pseudo header as used by TCP/UDP. It returns the | |
1743 | * checksum. | |
1744 | * | |
1745 | * For protocols that contain complete checksums such as ICMP/TCP/UDP, | |
1746 | * this function can be used to verify that checksum on received | |
1747 | * packets. In that case the function should return zero if the | |
1748 | * checksum is correct. In particular, this function will return zero | |
1749 | * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the | |
1750 | * hardware has already verified the correctness of the checksum. | |
1751 | */ | |
1752 | static inline __sum16 skb_checksum_complete(struct sk_buff *skb) | |
1753 | { | |
1754 | return skb_csum_unnecessary(skb) ? | |
1755 | 0 : __skb_checksum_complete(skb); | |
1756 | } | |
1757 | ||
1758 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1759 | extern void nf_conntrack_destroy(struct nf_conntrack *nfct); | |
1760 | static inline void nf_conntrack_put(struct nf_conntrack *nfct) | |
1761 | { | |
1762 | if (nfct && atomic_dec_and_test(&nfct->use)) | |
1763 | nf_conntrack_destroy(nfct); | |
1764 | } | |
1765 | static inline void nf_conntrack_get(struct nf_conntrack *nfct) | |
1766 | { | |
1767 | if (nfct) | |
1768 | atomic_inc(&nfct->use); | |
1769 | } | |
1770 | static inline void nf_conntrack_get_reasm(struct sk_buff *skb) | |
1771 | { | |
1772 | if (skb) | |
1773 | atomic_inc(&skb->users); | |
1774 | } | |
1775 | static inline void nf_conntrack_put_reasm(struct sk_buff *skb) | |
1776 | { | |
1777 | if (skb) | |
1778 | kfree_skb(skb); | |
1779 | } | |
1780 | #endif | |
1781 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1782 | static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) | |
1783 | { | |
1784 | if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) | |
1785 | kfree(nf_bridge); | |
1786 | } | |
1787 | static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) | |
1788 | { | |
1789 | if (nf_bridge) | |
1790 | atomic_inc(&nf_bridge->use); | |
1791 | } | |
1792 | #endif /* CONFIG_BRIDGE_NETFILTER */ | |
1793 | static inline void nf_reset(struct sk_buff *skb) | |
1794 | { | |
1795 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1796 | nf_conntrack_put(skb->nfct); | |
1797 | skb->nfct = NULL; | |
1798 | nf_conntrack_put_reasm(skb->nfct_reasm); | |
1799 | skb->nfct_reasm = NULL; | |
1800 | #endif | |
1801 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1802 | nf_bridge_put(skb->nf_bridge); | |
1803 | skb->nf_bridge = NULL; | |
1804 | #endif | |
1805 | } | |
1806 | ||
1807 | /* Note: This doesn't put any conntrack and bridge info in dst. */ | |
1808 | static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src) | |
1809 | { | |
1810 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1811 | dst->nfct = src->nfct; | |
1812 | nf_conntrack_get(src->nfct); | |
1813 | dst->nfctinfo = src->nfctinfo; | |
1814 | dst->nfct_reasm = src->nfct_reasm; | |
1815 | nf_conntrack_get_reasm(src->nfct_reasm); | |
1816 | #endif | |
1817 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1818 | dst->nf_bridge = src->nf_bridge; | |
1819 | nf_bridge_get(src->nf_bridge); | |
1820 | #endif | |
1821 | } | |
1822 | ||
1823 | static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) | |
1824 | { | |
1825 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
1826 | nf_conntrack_put(dst->nfct); | |
1827 | nf_conntrack_put_reasm(dst->nfct_reasm); | |
1828 | #endif | |
1829 | #ifdef CONFIG_BRIDGE_NETFILTER | |
1830 | nf_bridge_put(dst->nf_bridge); | |
1831 | #endif | |
1832 | __nf_copy(dst, src); | |
1833 | } | |
1834 | ||
1835 | #ifdef CONFIG_NETWORK_SECMARK | |
1836 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
1837 | { | |
1838 | to->secmark = from->secmark; | |
1839 | } | |
1840 | ||
1841 | static inline void skb_init_secmark(struct sk_buff *skb) | |
1842 | { | |
1843 | skb->secmark = 0; | |
1844 | } | |
1845 | #else | |
1846 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
1847 | { } | |
1848 | ||
1849 | static inline void skb_init_secmark(struct sk_buff *skb) | |
1850 | { } | |
1851 | #endif | |
1852 | ||
1853 | static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping) | |
1854 | { | |
1855 | skb->queue_mapping = queue_mapping; | |
1856 | } | |
1857 | ||
1858 | static inline u16 skb_get_queue_mapping(struct sk_buff *skb) | |
1859 | { | |
1860 | return skb->queue_mapping; | |
1861 | } | |
1862 | ||
1863 | static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from) | |
1864 | { | |
1865 | to->queue_mapping = from->queue_mapping; | |
1866 | } | |
1867 | ||
1868 | #ifdef CONFIG_XFRM | |
1869 | static inline struct sec_path *skb_sec_path(struct sk_buff *skb) | |
1870 | { | |
1871 | return skb->sp; | |
1872 | } | |
1873 | #else | |
1874 | static inline struct sec_path *skb_sec_path(struct sk_buff *skb) | |
1875 | { | |
1876 | return NULL; | |
1877 | } | |
1878 | #endif | |
1879 | ||
1880 | static inline int skb_is_gso(const struct sk_buff *skb) | |
1881 | { | |
1882 | return skb_shinfo(skb)->gso_size; | |
1883 | } | |
1884 | ||
1885 | static inline int skb_is_gso_v6(const struct sk_buff *skb) | |
1886 | { | |
1887 | return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6; | |
1888 | } | |
1889 | ||
1890 | extern void __skb_warn_lro_forwarding(const struct sk_buff *skb); | |
1891 | ||
1892 | static inline bool skb_warn_if_lro(const struct sk_buff *skb) | |
1893 | { | |
1894 | /* LRO sets gso_size but not gso_type, whereas if GSO is really | |
1895 | * wanted then gso_type will be set. */ | |
1896 | struct skb_shared_info *shinfo = skb_shinfo(skb); | |
1897 | if (shinfo->gso_size != 0 && unlikely(shinfo->gso_type == 0)) { | |
1898 | __skb_warn_lro_forwarding(skb); | |
1899 | return true; | |
1900 | } | |
1901 | return false; | |
1902 | } | |
1903 | ||
1904 | static inline void skb_forward_csum(struct sk_buff *skb) | |
1905 | { | |
1906 | /* Unfortunately we don't support this one. Any brave souls? */ | |
1907 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
1908 | skb->ip_summed = CHECKSUM_NONE; | |
1909 | } | |
1910 | ||
1911 | bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); | |
1912 | #endif /* __KERNEL__ */ | |
1913 | #endif /* _LINUX_SKBUFF_H */ |