Commit | Line | Data |
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1da177e4 LT |
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 | ||
1da177e4 | 17 | #include <linux/kernel.h> |
fe55f6d5 | 18 | #include <linux/kmemcheck.h> |
1da177e4 LT |
19 | #include <linux/compiler.h> |
20 | #include <linux/time.h> | |
187f1882 | 21 | #include <linux/bug.h> |
1da177e4 LT |
22 | #include <linux/cache.h> |
23 | ||
60063497 | 24 | #include <linux/atomic.h> |
1da177e4 LT |
25 | #include <asm/types.h> |
26 | #include <linux/spinlock.h> | |
1da177e4 | 27 | #include <linux/net.h> |
3fc7e8a6 | 28 | #include <linux/textsearch.h> |
1da177e4 | 29 | #include <net/checksum.h> |
a80958f4 | 30 | #include <linux/rcupdate.h> |
97fc2f08 | 31 | #include <linux/dmaengine.h> |
b7aa0bf7 | 32 | #include <linux/hrtimer.h> |
131ea667 | 33 | #include <linux/dma-mapping.h> |
c8f44aff | 34 | #include <linux/netdev_features.h> |
363ec392 | 35 | #include <linux/sched.h> |
5203cd28 | 36 | #include <net/flow_keys.h> |
1da177e4 | 37 | |
78ea85f1 DB |
38 | /* A. Checksumming of received packets by device. |
39 | * | |
40 | * CHECKSUM_NONE: | |
41 | * | |
42 | * Device failed to checksum this packet e.g. due to lack of capabilities. | |
43 | * The packet contains full (though not verified) checksum in packet but | |
44 | * not in skb->csum. Thus, skb->csum is undefined in this case. | |
45 | * | |
46 | * CHECKSUM_UNNECESSARY: | |
47 | * | |
48 | * The hardware you're dealing with doesn't calculate the full checksum | |
49 | * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums | |
77cffe23 TH |
50 | * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY |
51 | * if their checksums are okay. skb->csum is still undefined in this case | |
52 | * though. It is a bad option, but, unfortunately, nowadays most vendors do | |
53 | * this. Apparently with the secret goal to sell you new devices, when you | |
54 | * will add new protocol to your host, f.e. IPv6 8) | |
55 | * | |
56 | * CHECKSUM_UNNECESSARY is applicable to following protocols: | |
57 | * TCP: IPv6 and IPv4. | |
58 | * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a | |
59 | * zero UDP checksum for either IPv4 or IPv6, the networking stack | |
60 | * may perform further validation in this case. | |
61 | * GRE: only if the checksum is present in the header. | |
62 | * SCTP: indicates the CRC in SCTP header has been validated. | |
63 | * | |
64 | * skb->csum_level indicates the number of consecutive checksums found in | |
65 | * the packet minus one that have been verified as CHECKSUM_UNNECESSARY. | |
66 | * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet | |
67 | * and a device is able to verify the checksums for UDP (possibly zero), | |
68 | * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to | |
69 | * two. If the device were only able to verify the UDP checksum and not | |
70 | * GRE, either because it doesn't support GRE checksum of because GRE | |
71 | * checksum is bad, skb->csum_level would be set to zero (TCP checksum is | |
72 | * not considered in this case). | |
78ea85f1 DB |
73 | * |
74 | * CHECKSUM_COMPLETE: | |
75 | * | |
76 | * This is the most generic way. The device supplied checksum of the _whole_ | |
77 | * packet as seen by netif_rx() and fills out in skb->csum. Meaning, the | |
78 | * hardware doesn't need to parse L3/L4 headers to implement this. | |
79 | * | |
80 | * Note: Even if device supports only some protocols, but is able to produce | |
81 | * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY. | |
82 | * | |
83 | * CHECKSUM_PARTIAL: | |
84 | * | |
85 | * This is identical to the case for output below. This may occur on a packet | |
86 | * received directly from another Linux OS, e.g., a virtualized Linux kernel | |
87 | * on the same host. The packet can be treated in the same way as | |
88 | * CHECKSUM_UNNECESSARY, except that on output (i.e., forwarding) the | |
89 | * checksum must be filled in by the OS or the hardware. | |
90 | * | |
91 | * B. Checksumming on output. | |
92 | * | |
93 | * CHECKSUM_NONE: | |
94 | * | |
95 | * The skb was already checksummed by the protocol, or a checksum is not | |
96 | * required. | |
97 | * | |
98 | * CHECKSUM_PARTIAL: | |
99 | * | |
100 | * The device is required to checksum the packet as seen by hard_start_xmit() | |
101 | * from skb->csum_start up to the end, and to record/write the checksum at | |
102 | * offset skb->csum_start + skb->csum_offset. | |
103 | * | |
104 | * The device must show its capabilities in dev->features, set up at device | |
105 | * setup time, e.g. netdev_features.h: | |
106 | * | |
107 | * NETIF_F_HW_CSUM - It's a clever device, it's able to checksum everything. | |
108 | * NETIF_F_IP_CSUM - Device is dumb, it's able to checksum only TCP/UDP over | |
109 | * IPv4. Sigh. Vendors like this way for an unknown reason. | |
110 | * Though, see comment above about CHECKSUM_UNNECESSARY. 8) | |
111 | * NETIF_F_IPV6_CSUM - About as dumb as the last one but does IPv6 instead. | |
112 | * NETIF_F_... - Well, you get the picture. | |
113 | * | |
114 | * CHECKSUM_UNNECESSARY: | |
115 | * | |
116 | * Normally, the device will do per protocol specific checksumming. Protocol | |
117 | * implementations that do not want the NIC to perform the checksum | |
118 | * calculation should use this flag in their outgoing skbs. | |
119 | * | |
120 | * NETIF_F_FCOE_CRC - This indicates that the device can do FCoE FC CRC | |
121 | * offload. Correspondingly, the FCoE protocol driver | |
122 | * stack should use CHECKSUM_UNNECESSARY. | |
123 | * | |
124 | * Any questions? No questions, good. --ANK | |
125 | */ | |
126 | ||
60476372 | 127 | /* Don't change this without changing skb_csum_unnecessary! */ |
78ea85f1 DB |
128 | #define CHECKSUM_NONE 0 |
129 | #define CHECKSUM_UNNECESSARY 1 | |
130 | #define CHECKSUM_COMPLETE 2 | |
131 | #define CHECKSUM_PARTIAL 3 | |
1da177e4 | 132 | |
77cffe23 TH |
133 | /* Maximum value in skb->csum_level */ |
134 | #define SKB_MAX_CSUM_LEVEL 3 | |
135 | ||
0bec8c88 | 136 | #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES) |
fc910a27 | 137 | #define SKB_WITH_OVERHEAD(X) \ |
deea84b0 | 138 | ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) |
fc910a27 DM |
139 | #define SKB_MAX_ORDER(X, ORDER) \ |
140 | SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) | |
1da177e4 LT |
141 | #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) |
142 | #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) | |
143 | ||
87fb4b7b ED |
144 | /* return minimum truesize of one skb containing X bytes of data */ |
145 | #define SKB_TRUESIZE(X) ((X) + \ | |
146 | SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \ | |
147 | SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) | |
148 | ||
1da177e4 | 149 | struct net_device; |
716ea3a7 | 150 | struct scatterlist; |
9c55e01c | 151 | struct pipe_inode_info; |
1da177e4 | 152 | |
5f79e0f9 | 153 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
1da177e4 LT |
154 | struct nf_conntrack { |
155 | atomic_t use; | |
1da177e4 | 156 | }; |
5f79e0f9 | 157 | #endif |
1da177e4 LT |
158 | |
159 | #ifdef CONFIG_BRIDGE_NETFILTER | |
160 | struct nf_bridge_info { | |
bf1ac5ca ED |
161 | atomic_t use; |
162 | unsigned int mask; | |
163 | struct net_device *physindev; | |
164 | struct net_device *physoutdev; | |
165 | unsigned long data[32 / sizeof(unsigned long)]; | |
1da177e4 LT |
166 | }; |
167 | #endif | |
168 | ||
1da177e4 LT |
169 | struct sk_buff_head { |
170 | /* These two members must be first. */ | |
171 | struct sk_buff *next; | |
172 | struct sk_buff *prev; | |
173 | ||
174 | __u32 qlen; | |
175 | spinlock_t lock; | |
176 | }; | |
177 | ||
178 | struct sk_buff; | |
179 | ||
9d4dde52 IC |
180 | /* To allow 64K frame to be packed as single skb without frag_list we |
181 | * require 64K/PAGE_SIZE pages plus 1 additional page to allow for | |
182 | * buffers which do not start on a page boundary. | |
183 | * | |
184 | * Since GRO uses frags we allocate at least 16 regardless of page | |
185 | * size. | |
a715dea3 | 186 | */ |
9d4dde52 | 187 | #if (65536/PAGE_SIZE + 1) < 16 |
eec00954 | 188 | #define MAX_SKB_FRAGS 16UL |
a715dea3 | 189 | #else |
9d4dde52 | 190 | #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1) |
a715dea3 | 191 | #endif |
1da177e4 LT |
192 | |
193 | typedef struct skb_frag_struct skb_frag_t; | |
194 | ||
195 | struct skb_frag_struct { | |
a8605c60 IC |
196 | struct { |
197 | struct page *p; | |
198 | } page; | |
cb4dfe56 | 199 | #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536) |
a309bb07 DM |
200 | __u32 page_offset; |
201 | __u32 size; | |
cb4dfe56 ED |
202 | #else |
203 | __u16 page_offset; | |
204 | __u16 size; | |
205 | #endif | |
1da177e4 LT |
206 | }; |
207 | ||
9e903e08 ED |
208 | static inline unsigned int skb_frag_size(const skb_frag_t *frag) |
209 | { | |
210 | return frag->size; | |
211 | } | |
212 | ||
213 | static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) | |
214 | { | |
215 | frag->size = size; | |
216 | } | |
217 | ||
218 | static inline void skb_frag_size_add(skb_frag_t *frag, int delta) | |
219 | { | |
220 | frag->size += delta; | |
221 | } | |
222 | ||
223 | static inline void skb_frag_size_sub(skb_frag_t *frag, int delta) | |
224 | { | |
225 | frag->size -= delta; | |
226 | } | |
227 | ||
ac45f602 PO |
228 | #define HAVE_HW_TIME_STAMP |
229 | ||
230 | /** | |
d3a21be8 | 231 | * struct skb_shared_hwtstamps - hardware time stamps |
ac45f602 PO |
232 | * @hwtstamp: hardware time stamp transformed into duration |
233 | * since arbitrary point in time | |
ac45f602 PO |
234 | * |
235 | * Software time stamps generated by ktime_get_real() are stored in | |
4d276eb6 | 236 | * skb->tstamp. |
ac45f602 PO |
237 | * |
238 | * hwtstamps can only be compared against other hwtstamps from | |
239 | * the same device. | |
240 | * | |
241 | * This structure is attached to packets as part of the | |
242 | * &skb_shared_info. Use skb_hwtstamps() to get a pointer. | |
243 | */ | |
244 | struct skb_shared_hwtstamps { | |
245 | ktime_t hwtstamp; | |
ac45f602 PO |
246 | }; |
247 | ||
2244d07b OH |
248 | /* Definitions for tx_flags in struct skb_shared_info */ |
249 | enum { | |
250 | /* generate hardware time stamp */ | |
251 | SKBTX_HW_TSTAMP = 1 << 0, | |
252 | ||
e7fd2885 | 253 | /* generate software time stamp when queueing packet to NIC */ |
2244d07b OH |
254 | SKBTX_SW_TSTAMP = 1 << 1, |
255 | ||
256 | /* device driver is going to provide hardware time stamp */ | |
257 | SKBTX_IN_PROGRESS = 1 << 2, | |
258 | ||
a6686f2f | 259 | /* device driver supports TX zero-copy buffers */ |
62b1a8ab | 260 | SKBTX_DEV_ZEROCOPY = 1 << 3, |
6e3e939f JB |
261 | |
262 | /* generate wifi status information (where possible) */ | |
62b1a8ab | 263 | SKBTX_WIFI_STATUS = 1 << 4, |
c9af6db4 PS |
264 | |
265 | /* This indicates at least one fragment might be overwritten | |
266 | * (as in vmsplice(), sendfile() ...) | |
267 | * If we need to compute a TX checksum, we'll need to copy | |
268 | * all frags to avoid possible bad checksum | |
269 | */ | |
270 | SKBTX_SHARED_FRAG = 1 << 5, | |
e7fd2885 WB |
271 | |
272 | /* generate software time stamp when entering packet scheduling */ | |
273 | SKBTX_SCHED_TSTAMP = 1 << 6, | |
e1c8a607 WB |
274 | |
275 | /* generate software timestamp on peer data acknowledgment */ | |
276 | SKBTX_ACK_TSTAMP = 1 << 7, | |
a6686f2f SM |
277 | }; |
278 | ||
e1c8a607 WB |
279 | #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \ |
280 | SKBTX_SCHED_TSTAMP | \ | |
281 | SKBTX_ACK_TSTAMP) | |
f24b9be5 WB |
282 | #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP) |
283 | ||
a6686f2f SM |
284 | /* |
285 | * The callback notifies userspace to release buffers when skb DMA is done in | |
286 | * lower device, the skb last reference should be 0 when calling this. | |
e19d6763 MT |
287 | * The zerocopy_success argument is true if zero copy transmit occurred, |
288 | * false on data copy or out of memory error caused by data copy attempt. | |
ca8f4fb2 MT |
289 | * The ctx field is used to track device context. |
290 | * The desc field is used to track userspace buffer index. | |
a6686f2f SM |
291 | */ |
292 | struct ubuf_info { | |
e19d6763 | 293 | void (*callback)(struct ubuf_info *, bool zerocopy_success); |
ca8f4fb2 | 294 | void *ctx; |
a6686f2f | 295 | unsigned long desc; |
ac45f602 PO |
296 | }; |
297 | ||
1da177e4 LT |
298 | /* This data is invariant across clones and lives at |
299 | * the end of the header data, ie. at skb->end. | |
300 | */ | |
301 | struct skb_shared_info { | |
9f42f126 IC |
302 | unsigned char nr_frags; |
303 | __u8 tx_flags; | |
7967168c HX |
304 | unsigned short gso_size; |
305 | /* Warning: this field is not always filled in (UFO)! */ | |
306 | unsigned short gso_segs; | |
307 | unsigned short gso_type; | |
1da177e4 | 308 | struct sk_buff *frag_list; |
ac45f602 | 309 | struct skb_shared_hwtstamps hwtstamps; |
09c2d251 | 310 | u32 tskey; |
9f42f126 | 311 | __be32 ip6_frag_id; |
ec7d2f2c ED |
312 | |
313 | /* | |
314 | * Warning : all fields before dataref are cleared in __alloc_skb() | |
315 | */ | |
316 | atomic_t dataref; | |
317 | ||
69e3c75f JB |
318 | /* Intermediate layers must ensure that destructor_arg |
319 | * remains valid until skb destructor */ | |
320 | void * destructor_arg; | |
a6686f2f | 321 | |
fed66381 ED |
322 | /* must be last field, see pskb_expand_head() */ |
323 | skb_frag_t frags[MAX_SKB_FRAGS]; | |
1da177e4 LT |
324 | }; |
325 | ||
326 | /* We divide dataref into two halves. The higher 16 bits hold references | |
327 | * to the payload part of skb->data. The lower 16 bits hold references to | |
334a8132 PM |
328 | * the entire skb->data. A clone of a headerless skb holds the length of |
329 | * the header in skb->hdr_len. | |
1da177e4 LT |
330 | * |
331 | * All users must obey the rule that the skb->data reference count must be | |
332 | * greater than or equal to the payload reference count. | |
333 | * | |
334 | * Holding a reference to the payload part means that the user does not | |
335 | * care about modifications to the header part of skb->data. | |
336 | */ | |
337 | #define SKB_DATAREF_SHIFT 16 | |
338 | #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) | |
339 | ||
d179cd12 DM |
340 | |
341 | enum { | |
342 | SKB_FCLONE_UNAVAILABLE, | |
343 | SKB_FCLONE_ORIG, | |
344 | SKB_FCLONE_CLONE, | |
345 | }; | |
346 | ||
7967168c HX |
347 | enum { |
348 | SKB_GSO_TCPV4 = 1 << 0, | |
f83ef8c0 | 349 | SKB_GSO_UDP = 1 << 1, |
576a30eb HX |
350 | |
351 | /* This indicates the skb is from an untrusted source. */ | |
352 | SKB_GSO_DODGY = 1 << 2, | |
b0da8537 MC |
353 | |
354 | /* This indicates the tcp segment has CWR set. */ | |
f83ef8c0 HX |
355 | SKB_GSO_TCP_ECN = 1 << 3, |
356 | ||
357 | SKB_GSO_TCPV6 = 1 << 4, | |
01d5b2fc CL |
358 | |
359 | SKB_GSO_FCOE = 1 << 5, | |
68c33163 PS |
360 | |
361 | SKB_GSO_GRE = 1 << 6, | |
73136267 | 362 | |
4b28252c | 363 | SKB_GSO_GRE_CSUM = 1 << 7, |
0d89d203 | 364 | |
4b28252c | 365 | SKB_GSO_IPIP = 1 << 8, |
cb32f511 | 366 | |
4b28252c | 367 | SKB_GSO_SIT = 1 << 9, |
61c1db7f | 368 | |
4b28252c | 369 | SKB_GSO_UDP_TUNNEL = 1 << 10, |
0f4f4ffa TH |
370 | |
371 | SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11, | |
4749c09c | 372 | |
4b28252c TH |
373 | SKB_GSO_MPLS = 1 << 12, |
374 | ||
7967168c HX |
375 | }; |
376 | ||
2e07fa9c ACM |
377 | #if BITS_PER_LONG > 32 |
378 | #define NET_SKBUFF_DATA_USES_OFFSET 1 | |
379 | #endif | |
380 | ||
381 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
382 | typedef unsigned int sk_buff_data_t; | |
383 | #else | |
384 | typedef unsigned char *sk_buff_data_t; | |
385 | #endif | |
386 | ||
363ec392 ED |
387 | /** |
388 | * struct skb_mstamp - multi resolution time stamps | |
389 | * @stamp_us: timestamp in us resolution | |
390 | * @stamp_jiffies: timestamp in jiffies | |
391 | */ | |
392 | struct skb_mstamp { | |
393 | union { | |
394 | u64 v64; | |
395 | struct { | |
396 | u32 stamp_us; | |
397 | u32 stamp_jiffies; | |
398 | }; | |
399 | }; | |
400 | }; | |
401 | ||
402 | /** | |
403 | * skb_mstamp_get - get current timestamp | |
404 | * @cl: place to store timestamps | |
405 | */ | |
406 | static inline void skb_mstamp_get(struct skb_mstamp *cl) | |
407 | { | |
408 | u64 val = local_clock(); | |
409 | ||
410 | do_div(val, NSEC_PER_USEC); | |
411 | cl->stamp_us = (u32)val; | |
412 | cl->stamp_jiffies = (u32)jiffies; | |
413 | } | |
414 | ||
415 | /** | |
416 | * skb_mstamp_delta - compute the difference in usec between two skb_mstamp | |
417 | * @t1: pointer to newest sample | |
418 | * @t0: pointer to oldest sample | |
419 | */ | |
420 | static inline u32 skb_mstamp_us_delta(const struct skb_mstamp *t1, | |
421 | const struct skb_mstamp *t0) | |
422 | { | |
423 | s32 delta_us = t1->stamp_us - t0->stamp_us; | |
424 | u32 delta_jiffies = t1->stamp_jiffies - t0->stamp_jiffies; | |
425 | ||
426 | /* If delta_us is negative, this might be because interval is too big, | |
427 | * or local_clock() drift is too big : fallback using jiffies. | |
428 | */ | |
429 | if (delta_us <= 0 || | |
430 | delta_jiffies >= (INT_MAX / (USEC_PER_SEC / HZ))) | |
431 | ||
432 | delta_us = jiffies_to_usecs(delta_jiffies); | |
433 | ||
434 | return delta_us; | |
435 | } | |
436 | ||
437 | ||
1da177e4 LT |
438 | /** |
439 | * struct sk_buff - socket buffer | |
440 | * @next: Next buffer in list | |
441 | * @prev: Previous buffer in list | |
363ec392 | 442 | * @tstamp: Time we arrived/left |
d84e0bd7 | 443 | * @sk: Socket we are owned by |
1da177e4 | 444 | * @dev: Device we arrived on/are leaving by |
d84e0bd7 | 445 | * @cb: Control buffer. Free for use by every layer. Put private vars here |
7fee226a | 446 | * @_skb_refdst: destination entry (with norefcount bit) |
67be2dd1 | 447 | * @sp: the security path, used for xfrm |
1da177e4 LT |
448 | * @len: Length of actual data |
449 | * @data_len: Data length | |
450 | * @mac_len: Length of link layer header | |
334a8132 | 451 | * @hdr_len: writable header length of cloned skb |
663ead3b HX |
452 | * @csum: Checksum (must include start/offset pair) |
453 | * @csum_start: Offset from skb->head where checksumming should start | |
454 | * @csum_offset: Offset from csum_start where checksum should be stored | |
d84e0bd7 | 455 | * @priority: Packet queueing priority |
60ff7467 | 456 | * @ignore_df: allow local fragmentation |
1da177e4 | 457 | * @cloned: Head may be cloned (check refcnt to be sure) |
d84e0bd7 | 458 | * @ip_summed: Driver fed us an IP checksum |
1da177e4 | 459 | * @nohdr: Payload reference only, must not modify header |
d84e0bd7 | 460 | * @nfctinfo: Relationship of this skb to the connection |
1da177e4 | 461 | * @pkt_type: Packet class |
c83c2486 | 462 | * @fclone: skbuff clone status |
c83c2486 | 463 | * @ipvs_property: skbuff is owned by ipvs |
31729363 RD |
464 | * @peeked: this packet has been seen already, so stats have been |
465 | * done for it, don't do them again | |
ba9dda3a | 466 | * @nf_trace: netfilter packet trace flag |
d84e0bd7 DB |
467 | * @protocol: Packet protocol from driver |
468 | * @destructor: Destruct function | |
469 | * @nfct: Associated connection, if any | |
1da177e4 | 470 | * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c |
8964be4a | 471 | * @skb_iif: ifindex of device we arrived on |
1da177e4 LT |
472 | * @tc_index: Traffic control index |
473 | * @tc_verd: traffic control verdict | |
61b905da | 474 | * @hash: the packet hash |
d84e0bd7 | 475 | * @queue_mapping: Queue mapping for multiqueue devices |
0b725a2c | 476 | * @xmit_more: More SKBs are pending for this queue |
553a5672 | 477 | * @ndisc_nodetype: router type (from link layer) |
d84e0bd7 | 478 | * @ooo_okay: allow the mapping of a socket to a queue to be changed |
61b905da | 479 | * @l4_hash: indicate hash is a canonical 4-tuple hash over transport |
4ca2462e | 480 | * ports. |
a3b18ddb | 481 | * @sw_hash: indicates hash was computed in software stack |
6e3e939f JB |
482 | * @wifi_acked_valid: wifi_acked was set |
483 | * @wifi_acked: whether frame was acked on wifi or not | |
3bdc0eba | 484 | * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS |
f4b8ea78 RD |
485 | * @dma_cookie: a cookie to one of several possible DMA operations |
486 | * done by skb DMA functions | |
06021292 | 487 | * @napi_id: id of the NAPI struct this skb came from |
984bc16c | 488 | * @secmark: security marking |
d84e0bd7 DB |
489 | * @mark: Generic packet mark |
490 | * @dropcount: total number of sk_receive_queue overflows | |
86a9bad3 | 491 | * @vlan_proto: vlan encapsulation protocol |
6aa895b0 | 492 | * @vlan_tci: vlan tag control information |
0d89d203 | 493 | * @inner_protocol: Protocol (encapsulation) |
6a674e9c JG |
494 | * @inner_transport_header: Inner transport layer header (encapsulation) |
495 | * @inner_network_header: Network layer header (encapsulation) | |
aefbd2b3 | 496 | * @inner_mac_header: Link layer header (encapsulation) |
d84e0bd7 DB |
497 | * @transport_header: Transport layer header |
498 | * @network_header: Network layer header | |
499 | * @mac_header: Link layer header | |
500 | * @tail: Tail pointer | |
501 | * @end: End pointer | |
502 | * @head: Head of buffer | |
503 | * @data: Data head pointer | |
504 | * @truesize: Buffer size | |
505 | * @users: User count - see {datagram,tcp}.c | |
1da177e4 LT |
506 | */ |
507 | ||
508 | struct sk_buff { | |
509 | /* These two members must be first. */ | |
510 | struct sk_buff *next; | |
511 | struct sk_buff *prev; | |
512 | ||
363ec392 ED |
513 | union { |
514 | ktime_t tstamp; | |
515 | struct skb_mstamp skb_mstamp; | |
516 | }; | |
da3f5cf1 FF |
517 | |
518 | struct sock *sk; | |
1da177e4 | 519 | struct net_device *dev; |
1da177e4 | 520 | |
1da177e4 LT |
521 | /* |
522 | * This is the control buffer. It is free to use for every | |
523 | * layer. Please put your private variables there. If you | |
524 | * want to keep them across layers you have to do a skb_clone() | |
525 | * first. This is owned by whoever has the skb queued ATM. | |
526 | */ | |
da3f5cf1 | 527 | char cb[48] __aligned(8); |
1da177e4 | 528 | |
7fee226a | 529 | unsigned long _skb_refdst; |
b1937227 | 530 | void (*destructor)(struct sk_buff *skb); |
da3f5cf1 FF |
531 | #ifdef CONFIG_XFRM |
532 | struct sec_path *sp; | |
b1937227 ED |
533 | #endif |
534 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
535 | struct nf_conntrack *nfct; | |
536 | #endif | |
537 | #ifdef CONFIG_BRIDGE_NETFILTER | |
538 | struct nf_bridge_info *nf_bridge; | |
da3f5cf1 | 539 | #endif |
1da177e4 | 540 | unsigned int len, |
334a8132 PM |
541 | data_len; |
542 | __u16 mac_len, | |
543 | hdr_len; | |
b1937227 ED |
544 | |
545 | /* Following fields are _not_ copied in __copy_skb_header() | |
546 | * Note that queue_mapping is here mostly to fill a hole. | |
547 | */ | |
fe55f6d5 | 548 | kmemcheck_bitfield_begin(flags1); |
b1937227 ED |
549 | __u16 queue_mapping; |
550 | __u8 cloned:1, | |
6869c4d8 | 551 | nohdr:1, |
b1937227 ED |
552 | fclone:2, |
553 | peeked:1, | |
554 | head_frag:1, | |
555 | xmit_more:1; | |
556 | /* one bit hole */ | |
557 | kmemcheck_bitfield_end(flags1); | |
558 | ||
559 | ||
560 | ||
561 | /* fields enclosed in headers_start/headers_end are copied | |
562 | * using a single memcpy() in __copy_skb_header() | |
563 | */ | |
564 | __u32 headers_start[0]; | |
233577a2 HFS |
565 | |
566 | /* if you move pkt_type around you also must adapt those constants */ | |
567 | #ifdef __BIG_ENDIAN_BITFIELD | |
568 | #define PKT_TYPE_MAX (7 << 5) | |
569 | #else | |
570 | #define PKT_TYPE_MAX 7 | |
571 | #endif | |
572 | #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) | |
573 | ||
574 | __u8 __pkt_type_offset[0]; | |
b1937227 | 575 | __u8 pkt_type:3; |
c93bdd0e | 576 | __u8 pfmemalloc:1; |
b1937227 ED |
577 | __u8 ignore_df:1; |
578 | __u8 nfctinfo:3; | |
579 | ||
580 | __u8 nf_trace:1; | |
581 | __u8 ip_summed:2; | |
3853b584 | 582 | __u8 ooo_okay:1; |
61b905da | 583 | __u8 l4_hash:1; |
a3b18ddb | 584 | __u8 sw_hash:1; |
6e3e939f JB |
585 | __u8 wifi_acked_valid:1; |
586 | __u8 wifi_acked:1; | |
b1937227 | 587 | |
3bdc0eba | 588 | __u8 no_fcs:1; |
77cffe23 | 589 | /* Indicates the inner headers are valid in the skbuff. */ |
6a674e9c | 590 | __u8 encapsulation:1; |
7e2b10c1 | 591 | __u8 encap_hdr_csum:1; |
5d0c2b95 | 592 | __u8 csum_valid:1; |
7e3cead5 | 593 | __u8 csum_complete_sw:1; |
b1937227 ED |
594 | __u8 csum_level:2; |
595 | __u8 csum_bad:1; | |
fe55f6d5 | 596 | |
b1937227 ED |
597 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
598 | __u8 ndisc_nodetype:2; | |
599 | #endif | |
600 | __u8 ipvs_property:1; | |
601 | /* 5 or 7 bit hole */ | |
602 | ||
603 | #ifdef CONFIG_NET_SCHED | |
604 | __u16 tc_index; /* traffic control index */ | |
605 | #ifdef CONFIG_NET_CLS_ACT | |
606 | __u16 tc_verd; /* traffic control verdict */ | |
607 | #endif | |
608 | #endif | |
609 | ||
610 | union { | |
611 | __wsum csum; | |
612 | struct { | |
613 | __u16 csum_start; | |
614 | __u16 csum_offset; | |
615 | }; | |
616 | }; | |
617 | __u32 priority; | |
618 | int skb_iif; | |
619 | __u32 hash; | |
620 | __be16 vlan_proto; | |
621 | __u16 vlan_tci; | |
e0d1095a | 622 | #if defined CONFIG_NET_DMA || defined CONFIG_NET_RX_BUSY_POLL |
06021292 ET |
623 | union { |
624 | unsigned int napi_id; | |
625 | dma_cookie_t dma_cookie; | |
626 | }; | |
97fc2f08 | 627 | #endif |
984bc16c JM |
628 | #ifdef CONFIG_NETWORK_SECMARK |
629 | __u32 secmark; | |
630 | #endif | |
3b885787 NH |
631 | union { |
632 | __u32 mark; | |
633 | __u32 dropcount; | |
16fad69c | 634 | __u32 reserved_tailroom; |
3b885787 | 635 | }; |
1da177e4 | 636 | |
0d89d203 | 637 | __be16 inner_protocol; |
1a37e412 SH |
638 | __u16 inner_transport_header; |
639 | __u16 inner_network_header; | |
640 | __u16 inner_mac_header; | |
b1937227 ED |
641 | |
642 | __be16 protocol; | |
1a37e412 SH |
643 | __u16 transport_header; |
644 | __u16 network_header; | |
645 | __u16 mac_header; | |
b1937227 ED |
646 | |
647 | __u32 headers_end[0]; | |
648 | ||
1da177e4 | 649 | /* These elements must be at the end, see alloc_skb() for details. */ |
27a884dc | 650 | sk_buff_data_t tail; |
4305b541 | 651 | sk_buff_data_t end; |
1da177e4 | 652 | unsigned char *head, |
4305b541 | 653 | *data; |
27a884dc ACM |
654 | unsigned int truesize; |
655 | atomic_t users; | |
1da177e4 LT |
656 | }; |
657 | ||
658 | #ifdef __KERNEL__ | |
659 | /* | |
660 | * Handling routines are only of interest to the kernel | |
661 | */ | |
662 | #include <linux/slab.h> | |
663 | ||
1da177e4 | 664 | |
c93bdd0e MG |
665 | #define SKB_ALLOC_FCLONE 0x01 |
666 | #define SKB_ALLOC_RX 0x02 | |
667 | ||
668 | /* Returns true if the skb was allocated from PFMEMALLOC reserves */ | |
669 | static inline bool skb_pfmemalloc(const struct sk_buff *skb) | |
670 | { | |
671 | return unlikely(skb->pfmemalloc); | |
672 | } | |
673 | ||
7fee226a ED |
674 | /* |
675 | * skb might have a dst pointer attached, refcounted or not. | |
676 | * _skb_refdst low order bit is set if refcount was _not_ taken | |
677 | */ | |
678 | #define SKB_DST_NOREF 1UL | |
679 | #define SKB_DST_PTRMASK ~(SKB_DST_NOREF) | |
680 | ||
681 | /** | |
682 | * skb_dst - returns skb dst_entry | |
683 | * @skb: buffer | |
684 | * | |
685 | * Returns skb dst_entry, regardless of reference taken or not. | |
686 | */ | |
adf30907 ED |
687 | static inline struct dst_entry *skb_dst(const struct sk_buff *skb) |
688 | { | |
7fee226a ED |
689 | /* If refdst was not refcounted, check we still are in a |
690 | * rcu_read_lock section | |
691 | */ | |
692 | WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) && | |
693 | !rcu_read_lock_held() && | |
694 | !rcu_read_lock_bh_held()); | |
695 | return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK); | |
adf30907 ED |
696 | } |
697 | ||
7fee226a ED |
698 | /** |
699 | * skb_dst_set - sets skb dst | |
700 | * @skb: buffer | |
701 | * @dst: dst entry | |
702 | * | |
703 | * Sets skb dst, assuming a reference was taken on dst and should | |
704 | * be released by skb_dst_drop() | |
705 | */ | |
adf30907 ED |
706 | static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) |
707 | { | |
7fee226a ED |
708 | skb->_skb_refdst = (unsigned long)dst; |
709 | } | |
710 | ||
7965bd4d JP |
711 | void __skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst, |
712 | bool force); | |
932bc4d7 JA |
713 | |
714 | /** | |
715 | * skb_dst_set_noref - sets skb dst, hopefully, without taking reference | |
716 | * @skb: buffer | |
717 | * @dst: dst entry | |
718 | * | |
719 | * Sets skb dst, assuming a reference was not taken on dst. | |
720 | * If dst entry is cached, we do not take reference and dst_release | |
721 | * will be avoided by refdst_drop. If dst entry is not cached, we take | |
722 | * reference, so that last dst_release can destroy the dst immediately. | |
723 | */ | |
724 | static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst) | |
725 | { | |
726 | __skb_dst_set_noref(skb, dst, false); | |
727 | } | |
728 | ||
729 | /** | |
730 | * skb_dst_set_noref_force - sets skb dst, without taking reference | |
731 | * @skb: buffer | |
732 | * @dst: dst entry | |
733 | * | |
734 | * Sets skb dst, assuming a reference was not taken on dst. | |
735 | * No reference is taken and no dst_release will be called. While for | |
736 | * cached dsts deferred reclaim is a basic feature, for entries that are | |
737 | * not cached it is caller's job to guarantee that last dst_release for | |
738 | * provided dst happens when nobody uses it, eg. after a RCU grace period. | |
739 | */ | |
740 | static inline void skb_dst_set_noref_force(struct sk_buff *skb, | |
741 | struct dst_entry *dst) | |
742 | { | |
743 | __skb_dst_set_noref(skb, dst, true); | |
744 | } | |
7fee226a ED |
745 | |
746 | /** | |
25985edc | 747 | * skb_dst_is_noref - Test if skb dst isn't refcounted |
7fee226a ED |
748 | * @skb: buffer |
749 | */ | |
750 | static inline bool skb_dst_is_noref(const struct sk_buff *skb) | |
751 | { | |
752 | return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb); | |
adf30907 ED |
753 | } |
754 | ||
511c3f92 ED |
755 | static inline struct rtable *skb_rtable(const struct sk_buff *skb) |
756 | { | |
adf30907 | 757 | return (struct rtable *)skb_dst(skb); |
511c3f92 ED |
758 | } |
759 | ||
7965bd4d JP |
760 | void kfree_skb(struct sk_buff *skb); |
761 | void kfree_skb_list(struct sk_buff *segs); | |
762 | void skb_tx_error(struct sk_buff *skb); | |
763 | void consume_skb(struct sk_buff *skb); | |
764 | void __kfree_skb(struct sk_buff *skb); | |
d7e8883c | 765 | extern struct kmem_cache *skbuff_head_cache; |
bad43ca8 | 766 | |
7965bd4d JP |
767 | void kfree_skb_partial(struct sk_buff *skb, bool head_stolen); |
768 | bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, | |
769 | bool *fragstolen, int *delta_truesize); | |
bad43ca8 | 770 | |
7965bd4d JP |
771 | struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags, |
772 | int node); | |
773 | struct sk_buff *build_skb(void *data, unsigned int frag_size); | |
d179cd12 | 774 | static inline struct sk_buff *alloc_skb(unsigned int size, |
dd0fc66f | 775 | gfp_t priority) |
d179cd12 | 776 | { |
564824b0 | 777 | return __alloc_skb(size, priority, 0, NUMA_NO_NODE); |
d179cd12 DM |
778 | } |
779 | ||
2e4e4410 ED |
780 | struct sk_buff *alloc_skb_with_frags(unsigned long header_len, |
781 | unsigned long data_len, | |
782 | int max_page_order, | |
783 | int *errcode, | |
784 | gfp_t gfp_mask); | |
785 | ||
d179cd12 | 786 | static inline struct sk_buff *alloc_skb_fclone(unsigned int size, |
dd0fc66f | 787 | gfp_t priority) |
d179cd12 | 788 | { |
c93bdd0e | 789 | return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE); |
d179cd12 DM |
790 | } |
791 | ||
7965bd4d | 792 | struct sk_buff *__alloc_skb_head(gfp_t priority, int node); |
0ebd0ac5 PM |
793 | static inline struct sk_buff *alloc_skb_head(gfp_t priority) |
794 | { | |
795 | return __alloc_skb_head(priority, -1); | |
796 | } | |
797 | ||
7965bd4d JP |
798 | struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src); |
799 | int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask); | |
800 | struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority); | |
801 | struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority); | |
bad93e9d OP |
802 | struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom, |
803 | gfp_t gfp_mask, bool fclone); | |
804 | static inline struct sk_buff *__pskb_copy(struct sk_buff *skb, int headroom, | |
805 | gfp_t gfp_mask) | |
806 | { | |
807 | return __pskb_copy_fclone(skb, headroom, gfp_mask, false); | |
808 | } | |
7965bd4d JP |
809 | |
810 | int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, gfp_t gfp_mask); | |
811 | struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, | |
812 | unsigned int headroom); | |
813 | struct sk_buff *skb_copy_expand(const struct sk_buff *skb, int newheadroom, | |
814 | int newtailroom, gfp_t priority); | |
25a91d8d FD |
815 | int skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg, |
816 | int offset, int len); | |
7965bd4d JP |
817 | int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, |
818 | int len); | |
819 | int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer); | |
820 | int skb_pad(struct sk_buff *skb, int pad); | |
ead2ceb0 | 821 | #define dev_kfree_skb(a) consume_skb(a) |
1da177e4 | 822 | |
7965bd4d JP |
823 | int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, |
824 | int getfrag(void *from, char *to, int offset, | |
825 | int len, int odd, struct sk_buff *skb), | |
826 | void *from, int length); | |
e89e9cf5 | 827 | |
d94d9fee | 828 | struct skb_seq_state { |
677e90ed TG |
829 | __u32 lower_offset; |
830 | __u32 upper_offset; | |
831 | __u32 frag_idx; | |
832 | __u32 stepped_offset; | |
833 | struct sk_buff *root_skb; | |
834 | struct sk_buff *cur_skb; | |
835 | __u8 *frag_data; | |
836 | }; | |
837 | ||
7965bd4d JP |
838 | void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, |
839 | unsigned int to, struct skb_seq_state *st); | |
840 | unsigned int skb_seq_read(unsigned int consumed, const u8 **data, | |
841 | struct skb_seq_state *st); | |
842 | void skb_abort_seq_read(struct skb_seq_state *st); | |
677e90ed | 843 | |
7965bd4d JP |
844 | unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, |
845 | unsigned int to, struct ts_config *config, | |
846 | struct ts_state *state); | |
3fc7e8a6 | 847 | |
09323cc4 TH |
848 | /* |
849 | * Packet hash types specify the type of hash in skb_set_hash. | |
850 | * | |
851 | * Hash types refer to the protocol layer addresses which are used to | |
852 | * construct a packet's hash. The hashes are used to differentiate or identify | |
853 | * flows of the protocol layer for the hash type. Hash types are either | |
854 | * layer-2 (L2), layer-3 (L3), or layer-4 (L4). | |
855 | * | |
856 | * Properties of hashes: | |
857 | * | |
858 | * 1) Two packets in different flows have different hash values | |
859 | * 2) Two packets in the same flow should have the same hash value | |
860 | * | |
861 | * A hash at a higher layer is considered to be more specific. A driver should | |
862 | * set the most specific hash possible. | |
863 | * | |
864 | * A driver cannot indicate a more specific hash than the layer at which a hash | |
865 | * was computed. For instance an L3 hash cannot be set as an L4 hash. | |
866 | * | |
867 | * A driver may indicate a hash level which is less specific than the | |
868 | * actual layer the hash was computed on. For instance, a hash computed | |
869 | * at L4 may be considered an L3 hash. This should only be done if the | |
870 | * driver can't unambiguously determine that the HW computed the hash at | |
871 | * the higher layer. Note that the "should" in the second property above | |
872 | * permits this. | |
873 | */ | |
874 | enum pkt_hash_types { | |
875 | PKT_HASH_TYPE_NONE, /* Undefined type */ | |
876 | PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */ | |
877 | PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */ | |
878 | PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */ | |
879 | }; | |
880 | ||
881 | static inline void | |
882 | skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type) | |
883 | { | |
61b905da | 884 | skb->l4_hash = (type == PKT_HASH_TYPE_L4); |
a3b18ddb | 885 | skb->sw_hash = 0; |
61b905da | 886 | skb->hash = hash; |
09323cc4 TH |
887 | } |
888 | ||
3958afa1 TH |
889 | void __skb_get_hash(struct sk_buff *skb); |
890 | static inline __u32 skb_get_hash(struct sk_buff *skb) | |
bfb564e7 | 891 | { |
a3b18ddb | 892 | if (!skb->l4_hash && !skb->sw_hash) |
3958afa1 | 893 | __skb_get_hash(skb); |
bfb564e7 | 894 | |
61b905da | 895 | return skb->hash; |
bfb564e7 KK |
896 | } |
897 | ||
57bdf7f4 TH |
898 | static inline __u32 skb_get_hash_raw(const struct sk_buff *skb) |
899 | { | |
61b905da | 900 | return skb->hash; |
57bdf7f4 TH |
901 | } |
902 | ||
7539fadc TH |
903 | static inline void skb_clear_hash(struct sk_buff *skb) |
904 | { | |
61b905da | 905 | skb->hash = 0; |
a3b18ddb | 906 | skb->sw_hash = 0; |
61b905da | 907 | skb->l4_hash = 0; |
7539fadc TH |
908 | } |
909 | ||
910 | static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb) | |
911 | { | |
61b905da | 912 | if (!skb->l4_hash) |
7539fadc TH |
913 | skb_clear_hash(skb); |
914 | } | |
915 | ||
3df7a74e TH |
916 | static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from) |
917 | { | |
61b905da | 918 | to->hash = from->hash; |
a3b18ddb | 919 | to->sw_hash = from->sw_hash; |
61b905da | 920 | to->l4_hash = from->l4_hash; |
3df7a74e TH |
921 | }; |
922 | ||
4305b541 ACM |
923 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
924 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
925 | { | |
926 | return skb->head + skb->end; | |
927 | } | |
ec47ea82 AD |
928 | |
929 | static inline unsigned int skb_end_offset(const struct sk_buff *skb) | |
930 | { | |
931 | return skb->end; | |
932 | } | |
4305b541 ACM |
933 | #else |
934 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
935 | { | |
936 | return skb->end; | |
937 | } | |
ec47ea82 AD |
938 | |
939 | static inline unsigned int skb_end_offset(const struct sk_buff *skb) | |
940 | { | |
941 | return skb->end - skb->head; | |
942 | } | |
4305b541 ACM |
943 | #endif |
944 | ||
1da177e4 | 945 | /* Internal */ |
4305b541 | 946 | #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) |
1da177e4 | 947 | |
ac45f602 PO |
948 | static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb) |
949 | { | |
950 | return &skb_shinfo(skb)->hwtstamps; | |
951 | } | |
952 | ||
1da177e4 LT |
953 | /** |
954 | * skb_queue_empty - check if a queue is empty | |
955 | * @list: queue head | |
956 | * | |
957 | * Returns true if the queue is empty, false otherwise. | |
958 | */ | |
959 | static inline int skb_queue_empty(const struct sk_buff_head *list) | |
960 | { | |
fd44b93c | 961 | return list->next == (const struct sk_buff *) list; |
1da177e4 LT |
962 | } |
963 | ||
fc7ebb21 DM |
964 | /** |
965 | * skb_queue_is_last - check if skb is the last entry in the queue | |
966 | * @list: queue head | |
967 | * @skb: buffer | |
968 | * | |
969 | * Returns true if @skb is the last buffer on the list. | |
970 | */ | |
971 | static inline bool skb_queue_is_last(const struct sk_buff_head *list, | |
972 | const struct sk_buff *skb) | |
973 | { | |
fd44b93c | 974 | return skb->next == (const struct sk_buff *) list; |
fc7ebb21 DM |
975 | } |
976 | ||
832d11c5 IJ |
977 | /** |
978 | * skb_queue_is_first - check if skb is the first entry in the queue | |
979 | * @list: queue head | |
980 | * @skb: buffer | |
981 | * | |
982 | * Returns true if @skb is the first buffer on the list. | |
983 | */ | |
984 | static inline bool skb_queue_is_first(const struct sk_buff_head *list, | |
985 | const struct sk_buff *skb) | |
986 | { | |
fd44b93c | 987 | return skb->prev == (const struct sk_buff *) list; |
832d11c5 IJ |
988 | } |
989 | ||
249c8b42 DM |
990 | /** |
991 | * skb_queue_next - return the next packet in the queue | |
992 | * @list: queue head | |
993 | * @skb: current buffer | |
994 | * | |
995 | * Return the next packet in @list after @skb. It is only valid to | |
996 | * call this if skb_queue_is_last() evaluates to false. | |
997 | */ | |
998 | static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list, | |
999 | const struct sk_buff *skb) | |
1000 | { | |
1001 | /* This BUG_ON may seem severe, but if we just return then we | |
1002 | * are going to dereference garbage. | |
1003 | */ | |
1004 | BUG_ON(skb_queue_is_last(list, skb)); | |
1005 | return skb->next; | |
1006 | } | |
1007 | ||
832d11c5 IJ |
1008 | /** |
1009 | * skb_queue_prev - return the prev packet in the queue | |
1010 | * @list: queue head | |
1011 | * @skb: current buffer | |
1012 | * | |
1013 | * Return the prev packet in @list before @skb. It is only valid to | |
1014 | * call this if skb_queue_is_first() evaluates to false. | |
1015 | */ | |
1016 | static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list, | |
1017 | const struct sk_buff *skb) | |
1018 | { | |
1019 | /* This BUG_ON may seem severe, but if we just return then we | |
1020 | * are going to dereference garbage. | |
1021 | */ | |
1022 | BUG_ON(skb_queue_is_first(list, skb)); | |
1023 | return skb->prev; | |
1024 | } | |
1025 | ||
1da177e4 LT |
1026 | /** |
1027 | * skb_get - reference buffer | |
1028 | * @skb: buffer to reference | |
1029 | * | |
1030 | * Makes another reference to a socket buffer and returns a pointer | |
1031 | * to the buffer. | |
1032 | */ | |
1033 | static inline struct sk_buff *skb_get(struct sk_buff *skb) | |
1034 | { | |
1035 | atomic_inc(&skb->users); | |
1036 | return skb; | |
1037 | } | |
1038 | ||
1039 | /* | |
1040 | * If users == 1, we are the only owner and are can avoid redundant | |
1041 | * atomic change. | |
1042 | */ | |
1043 | ||
1da177e4 LT |
1044 | /** |
1045 | * skb_cloned - is the buffer a clone | |
1046 | * @skb: buffer to check | |
1047 | * | |
1048 | * Returns true if the buffer was generated with skb_clone() and is | |
1049 | * one of multiple shared copies of the buffer. Cloned buffers are | |
1050 | * shared data so must not be written to under normal circumstances. | |
1051 | */ | |
1052 | static inline int skb_cloned(const struct sk_buff *skb) | |
1053 | { | |
1054 | return skb->cloned && | |
1055 | (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; | |
1056 | } | |
1057 | ||
14bbd6a5 PS |
1058 | static inline int skb_unclone(struct sk_buff *skb, gfp_t pri) |
1059 | { | |
1060 | might_sleep_if(pri & __GFP_WAIT); | |
1061 | ||
1062 | if (skb_cloned(skb)) | |
1063 | return pskb_expand_head(skb, 0, 0, pri); | |
1064 | ||
1065 | return 0; | |
1066 | } | |
1067 | ||
1da177e4 LT |
1068 | /** |
1069 | * skb_header_cloned - is the header a clone | |
1070 | * @skb: buffer to check | |
1071 | * | |
1072 | * Returns true if modifying the header part of the buffer requires | |
1073 | * the data to be copied. | |
1074 | */ | |
1075 | static inline int skb_header_cloned(const struct sk_buff *skb) | |
1076 | { | |
1077 | int dataref; | |
1078 | ||
1079 | if (!skb->cloned) | |
1080 | return 0; | |
1081 | ||
1082 | dataref = atomic_read(&skb_shinfo(skb)->dataref); | |
1083 | dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); | |
1084 | return dataref != 1; | |
1085 | } | |
1086 | ||
1087 | /** | |
1088 | * skb_header_release - release reference to header | |
1089 | * @skb: buffer to operate on | |
1090 | * | |
1091 | * Drop a reference to the header part of the buffer. This is done | |
1092 | * by acquiring a payload reference. You must not read from the header | |
1093 | * part of skb->data after this. | |
f4a775d1 | 1094 | * Note : Check if you can use __skb_header_release() instead. |
1da177e4 LT |
1095 | */ |
1096 | static inline void skb_header_release(struct sk_buff *skb) | |
1097 | { | |
1098 | BUG_ON(skb->nohdr); | |
1099 | skb->nohdr = 1; | |
1100 | atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); | |
1101 | } | |
1102 | ||
f4a775d1 ED |
1103 | /** |
1104 | * __skb_header_release - release reference to header | |
1105 | * @skb: buffer to operate on | |
1106 | * | |
1107 | * Variant of skb_header_release() assuming skb is private to caller. | |
1108 | * We can avoid one atomic operation. | |
1109 | */ | |
1110 | static inline void __skb_header_release(struct sk_buff *skb) | |
1111 | { | |
1112 | skb->nohdr = 1; | |
1113 | atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT)); | |
1114 | } | |
1115 | ||
1116 | ||
1da177e4 LT |
1117 | /** |
1118 | * skb_shared - is the buffer shared | |
1119 | * @skb: buffer to check | |
1120 | * | |
1121 | * Returns true if more than one person has a reference to this | |
1122 | * buffer. | |
1123 | */ | |
1124 | static inline int skb_shared(const struct sk_buff *skb) | |
1125 | { | |
1126 | return atomic_read(&skb->users) != 1; | |
1127 | } | |
1128 | ||
1129 | /** | |
1130 | * skb_share_check - check if buffer is shared and if so clone it | |
1131 | * @skb: buffer to check | |
1132 | * @pri: priority for memory allocation | |
1133 | * | |
1134 | * If the buffer is shared the buffer is cloned and the old copy | |
1135 | * drops a reference. A new clone with a single reference is returned. | |
1136 | * If the buffer is not shared the original buffer is returned. When | |
1137 | * being called from interrupt status or with spinlocks held pri must | |
1138 | * be GFP_ATOMIC. | |
1139 | * | |
1140 | * NULL is returned on a memory allocation failure. | |
1141 | */ | |
47061bc4 | 1142 | static inline struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri) |
1da177e4 LT |
1143 | { |
1144 | might_sleep_if(pri & __GFP_WAIT); | |
1145 | if (skb_shared(skb)) { | |
1146 | struct sk_buff *nskb = skb_clone(skb, pri); | |
47061bc4 ED |
1147 | |
1148 | if (likely(nskb)) | |
1149 | consume_skb(skb); | |
1150 | else | |
1151 | kfree_skb(skb); | |
1da177e4 LT |
1152 | skb = nskb; |
1153 | } | |
1154 | return skb; | |
1155 | } | |
1156 | ||
1157 | /* | |
1158 | * Copy shared buffers into a new sk_buff. We effectively do COW on | |
1159 | * packets to handle cases where we have a local reader and forward | |
1160 | * and a couple of other messy ones. The normal one is tcpdumping | |
1161 | * a packet thats being forwarded. | |
1162 | */ | |
1163 | ||
1164 | /** | |
1165 | * skb_unshare - make a copy of a shared buffer | |
1166 | * @skb: buffer to check | |
1167 | * @pri: priority for memory allocation | |
1168 | * | |
1169 | * If the socket buffer is a clone then this function creates a new | |
1170 | * copy of the data, drops a reference count on the old copy and returns | |
1171 | * the new copy with the reference count at 1. If the buffer is not a clone | |
1172 | * the original buffer is returned. When called with a spinlock held or | |
1173 | * from interrupt state @pri must be %GFP_ATOMIC | |
1174 | * | |
1175 | * %NULL is returned on a memory allocation failure. | |
1176 | */ | |
e2bf521d | 1177 | static inline struct sk_buff *skb_unshare(struct sk_buff *skb, |
dd0fc66f | 1178 | gfp_t pri) |
1da177e4 LT |
1179 | { |
1180 | might_sleep_if(pri & __GFP_WAIT); | |
1181 | if (skb_cloned(skb)) { | |
1182 | struct sk_buff *nskb = skb_copy(skb, pri); | |
1183 | kfree_skb(skb); /* Free our shared copy */ | |
1184 | skb = nskb; | |
1185 | } | |
1186 | return skb; | |
1187 | } | |
1188 | ||
1189 | /** | |
1a5778aa | 1190 | * skb_peek - peek at the head of an &sk_buff_head |
1da177e4 LT |
1191 | * @list_: list to peek at |
1192 | * | |
1193 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
1194 | * be careful with this one. A peek leaves the buffer on the | |
1195 | * list and someone else may run off with it. You must hold | |
1196 | * the appropriate locks or have a private queue to do this. | |
1197 | * | |
1198 | * Returns %NULL for an empty list or a pointer to the head element. | |
1199 | * The reference count is not incremented and the reference is therefore | |
1200 | * volatile. Use with caution. | |
1201 | */ | |
05bdd2f1 | 1202 | static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_) |
1da177e4 | 1203 | { |
18d07000 ED |
1204 | struct sk_buff *skb = list_->next; |
1205 | ||
1206 | if (skb == (struct sk_buff *)list_) | |
1207 | skb = NULL; | |
1208 | return skb; | |
1da177e4 LT |
1209 | } |
1210 | ||
da5ef6e5 PE |
1211 | /** |
1212 | * skb_peek_next - peek skb following the given one from a queue | |
1213 | * @skb: skb to start from | |
1214 | * @list_: list to peek at | |
1215 | * | |
1216 | * Returns %NULL when the end of the list is met or a pointer to the | |
1217 | * next element. The reference count is not incremented and the | |
1218 | * reference is therefore volatile. Use with caution. | |
1219 | */ | |
1220 | static inline struct sk_buff *skb_peek_next(struct sk_buff *skb, | |
1221 | const struct sk_buff_head *list_) | |
1222 | { | |
1223 | struct sk_buff *next = skb->next; | |
18d07000 | 1224 | |
da5ef6e5 PE |
1225 | if (next == (struct sk_buff *)list_) |
1226 | next = NULL; | |
1227 | return next; | |
1228 | } | |
1229 | ||
1da177e4 | 1230 | /** |
1a5778aa | 1231 | * skb_peek_tail - peek at the tail of an &sk_buff_head |
1da177e4 LT |
1232 | * @list_: list to peek at |
1233 | * | |
1234 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
1235 | * be careful with this one. A peek leaves the buffer on the | |
1236 | * list and someone else may run off with it. You must hold | |
1237 | * the appropriate locks or have a private queue to do this. | |
1238 | * | |
1239 | * Returns %NULL for an empty list or a pointer to the tail element. | |
1240 | * The reference count is not incremented and the reference is therefore | |
1241 | * volatile. Use with caution. | |
1242 | */ | |
05bdd2f1 | 1243 | static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_) |
1da177e4 | 1244 | { |
18d07000 ED |
1245 | struct sk_buff *skb = list_->prev; |
1246 | ||
1247 | if (skb == (struct sk_buff *)list_) | |
1248 | skb = NULL; | |
1249 | return skb; | |
1250 | ||
1da177e4 LT |
1251 | } |
1252 | ||
1253 | /** | |
1254 | * skb_queue_len - get queue length | |
1255 | * @list_: list to measure | |
1256 | * | |
1257 | * Return the length of an &sk_buff queue. | |
1258 | */ | |
1259 | static inline __u32 skb_queue_len(const struct sk_buff_head *list_) | |
1260 | { | |
1261 | return list_->qlen; | |
1262 | } | |
1263 | ||
67fed459 DM |
1264 | /** |
1265 | * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head | |
1266 | * @list: queue to initialize | |
1267 | * | |
1268 | * This initializes only the list and queue length aspects of | |
1269 | * an sk_buff_head object. This allows to initialize the list | |
1270 | * aspects of an sk_buff_head without reinitializing things like | |
1271 | * the spinlock. It can also be used for on-stack sk_buff_head | |
1272 | * objects where the spinlock is known to not be used. | |
1273 | */ | |
1274 | static inline void __skb_queue_head_init(struct sk_buff_head *list) | |
1275 | { | |
1276 | list->prev = list->next = (struct sk_buff *)list; | |
1277 | list->qlen = 0; | |
1278 | } | |
1279 | ||
76f10ad0 AV |
1280 | /* |
1281 | * This function creates a split out lock class for each invocation; | |
1282 | * this is needed for now since a whole lot of users of the skb-queue | |
1283 | * infrastructure in drivers have different locking usage (in hardirq) | |
1284 | * than the networking core (in softirq only). In the long run either the | |
1285 | * network layer or drivers should need annotation to consolidate the | |
1286 | * main types of usage into 3 classes. | |
1287 | */ | |
1da177e4 LT |
1288 | static inline void skb_queue_head_init(struct sk_buff_head *list) |
1289 | { | |
1290 | spin_lock_init(&list->lock); | |
67fed459 | 1291 | __skb_queue_head_init(list); |
1da177e4 LT |
1292 | } |
1293 | ||
c2ecba71 PE |
1294 | static inline void skb_queue_head_init_class(struct sk_buff_head *list, |
1295 | struct lock_class_key *class) | |
1296 | { | |
1297 | skb_queue_head_init(list); | |
1298 | lockdep_set_class(&list->lock, class); | |
1299 | } | |
1300 | ||
1da177e4 | 1301 | /* |
bf299275 | 1302 | * Insert an sk_buff on a list. |
1da177e4 LT |
1303 | * |
1304 | * The "__skb_xxxx()" functions are the non-atomic ones that | |
1305 | * can only be called with interrupts disabled. | |
1306 | */ | |
7965bd4d JP |
1307 | void skb_insert(struct sk_buff *old, struct sk_buff *newsk, |
1308 | struct sk_buff_head *list); | |
bf299275 GR |
1309 | static inline void __skb_insert(struct sk_buff *newsk, |
1310 | struct sk_buff *prev, struct sk_buff *next, | |
1311 | struct sk_buff_head *list) | |
1312 | { | |
1313 | newsk->next = next; | |
1314 | newsk->prev = prev; | |
1315 | next->prev = prev->next = newsk; | |
1316 | list->qlen++; | |
1317 | } | |
1da177e4 | 1318 | |
67fed459 DM |
1319 | static inline void __skb_queue_splice(const struct sk_buff_head *list, |
1320 | struct sk_buff *prev, | |
1321 | struct sk_buff *next) | |
1322 | { | |
1323 | struct sk_buff *first = list->next; | |
1324 | struct sk_buff *last = list->prev; | |
1325 | ||
1326 | first->prev = prev; | |
1327 | prev->next = first; | |
1328 | ||
1329 | last->next = next; | |
1330 | next->prev = last; | |
1331 | } | |
1332 | ||
1333 | /** | |
1334 | * skb_queue_splice - join two skb lists, this is designed for stacks | |
1335 | * @list: the new list to add | |
1336 | * @head: the place to add it in the first list | |
1337 | */ | |
1338 | static inline void skb_queue_splice(const struct sk_buff_head *list, | |
1339 | struct sk_buff_head *head) | |
1340 | { | |
1341 | if (!skb_queue_empty(list)) { | |
1342 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
1d4a31dd | 1343 | head->qlen += list->qlen; |
67fed459 DM |
1344 | } |
1345 | } | |
1346 | ||
1347 | /** | |
d9619496 | 1348 | * skb_queue_splice_init - join two skb lists and reinitialise the emptied list |
67fed459 DM |
1349 | * @list: the new list to add |
1350 | * @head: the place to add it in the first list | |
1351 | * | |
1352 | * The list at @list is reinitialised | |
1353 | */ | |
1354 | static inline void skb_queue_splice_init(struct sk_buff_head *list, | |
1355 | struct sk_buff_head *head) | |
1356 | { | |
1357 | if (!skb_queue_empty(list)) { | |
1358 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
1d4a31dd | 1359 | head->qlen += list->qlen; |
67fed459 DM |
1360 | __skb_queue_head_init(list); |
1361 | } | |
1362 | } | |
1363 | ||
1364 | /** | |
1365 | * skb_queue_splice_tail - join two skb lists, each list being a queue | |
1366 | * @list: the new list to add | |
1367 | * @head: the place to add it in the first list | |
1368 | */ | |
1369 | static inline void skb_queue_splice_tail(const struct sk_buff_head *list, | |
1370 | struct sk_buff_head *head) | |
1371 | { | |
1372 | if (!skb_queue_empty(list)) { | |
1373 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
1d4a31dd | 1374 | head->qlen += list->qlen; |
67fed459 DM |
1375 | } |
1376 | } | |
1377 | ||
1378 | /** | |
d9619496 | 1379 | * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list |
67fed459 DM |
1380 | * @list: the new list to add |
1381 | * @head: the place to add it in the first list | |
1382 | * | |
1383 | * Each of the lists is a queue. | |
1384 | * The list at @list is reinitialised | |
1385 | */ | |
1386 | static inline void skb_queue_splice_tail_init(struct sk_buff_head *list, | |
1387 | struct sk_buff_head *head) | |
1388 | { | |
1389 | if (!skb_queue_empty(list)) { | |
1390 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
1d4a31dd | 1391 | head->qlen += list->qlen; |
67fed459 DM |
1392 | __skb_queue_head_init(list); |
1393 | } | |
1394 | } | |
1395 | ||
1da177e4 | 1396 | /** |
300ce174 | 1397 | * __skb_queue_after - queue a buffer at the list head |
1da177e4 | 1398 | * @list: list to use |
300ce174 | 1399 | * @prev: place after this buffer |
1da177e4 LT |
1400 | * @newsk: buffer to queue |
1401 | * | |
300ce174 | 1402 | * Queue a buffer int the middle of a list. This function takes no locks |
1da177e4 LT |
1403 | * and you must therefore hold required locks before calling it. |
1404 | * | |
1405 | * A buffer cannot be placed on two lists at the same time. | |
1406 | */ | |
300ce174 SH |
1407 | static inline void __skb_queue_after(struct sk_buff_head *list, |
1408 | struct sk_buff *prev, | |
1409 | struct sk_buff *newsk) | |
1da177e4 | 1410 | { |
bf299275 | 1411 | __skb_insert(newsk, prev, prev->next, list); |
1da177e4 LT |
1412 | } |
1413 | ||
7965bd4d JP |
1414 | void skb_append(struct sk_buff *old, struct sk_buff *newsk, |
1415 | struct sk_buff_head *list); | |
7de6c033 | 1416 | |
f5572855 GR |
1417 | static inline void __skb_queue_before(struct sk_buff_head *list, |
1418 | struct sk_buff *next, | |
1419 | struct sk_buff *newsk) | |
1420 | { | |
1421 | __skb_insert(newsk, next->prev, next, list); | |
1422 | } | |
1423 | ||
300ce174 SH |
1424 | /** |
1425 | * __skb_queue_head - queue a buffer at the list head | |
1426 | * @list: list to use | |
1427 | * @newsk: buffer to queue | |
1428 | * | |
1429 | * Queue a buffer at the start of a list. This function takes no locks | |
1430 | * and you must therefore hold required locks before calling it. | |
1431 | * | |
1432 | * A buffer cannot be placed on two lists at the same time. | |
1433 | */ | |
7965bd4d | 1434 | void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); |
300ce174 SH |
1435 | static inline void __skb_queue_head(struct sk_buff_head *list, |
1436 | struct sk_buff *newsk) | |
1437 | { | |
1438 | __skb_queue_after(list, (struct sk_buff *)list, newsk); | |
1439 | } | |
1440 | ||
1da177e4 LT |
1441 | /** |
1442 | * __skb_queue_tail - queue a buffer at the list tail | |
1443 | * @list: list to use | |
1444 | * @newsk: buffer to queue | |
1445 | * | |
1446 | * Queue a buffer at the end of a list. This function takes no locks | |
1447 | * and you must therefore hold required locks before calling it. | |
1448 | * | |
1449 | * A buffer cannot be placed on two lists at the same time. | |
1450 | */ | |
7965bd4d | 1451 | void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); |
1da177e4 LT |
1452 | static inline void __skb_queue_tail(struct sk_buff_head *list, |
1453 | struct sk_buff *newsk) | |
1454 | { | |
f5572855 | 1455 | __skb_queue_before(list, (struct sk_buff *)list, newsk); |
1da177e4 LT |
1456 | } |
1457 | ||
1da177e4 LT |
1458 | /* |
1459 | * remove sk_buff from list. _Must_ be called atomically, and with | |
1460 | * the list known.. | |
1461 | */ | |
7965bd4d | 1462 | void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); |
1da177e4 LT |
1463 | static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) |
1464 | { | |
1465 | struct sk_buff *next, *prev; | |
1466 | ||
1467 | list->qlen--; | |
1468 | next = skb->next; | |
1469 | prev = skb->prev; | |
1470 | skb->next = skb->prev = NULL; | |
1da177e4 LT |
1471 | next->prev = prev; |
1472 | prev->next = next; | |
1473 | } | |
1474 | ||
f525c06d GR |
1475 | /** |
1476 | * __skb_dequeue - remove from the head of the queue | |
1477 | * @list: list to dequeue from | |
1478 | * | |
1479 | * Remove the head of the list. This function does not take any locks | |
1480 | * so must be used with appropriate locks held only. The head item is | |
1481 | * returned or %NULL if the list is empty. | |
1482 | */ | |
7965bd4d | 1483 | struct sk_buff *skb_dequeue(struct sk_buff_head *list); |
f525c06d GR |
1484 | static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) |
1485 | { | |
1486 | struct sk_buff *skb = skb_peek(list); | |
1487 | if (skb) | |
1488 | __skb_unlink(skb, list); | |
1489 | return skb; | |
1490 | } | |
1da177e4 LT |
1491 | |
1492 | /** | |
1493 | * __skb_dequeue_tail - remove from the tail of the queue | |
1494 | * @list: list to dequeue from | |
1495 | * | |
1496 | * Remove the tail of the list. This function does not take any locks | |
1497 | * so must be used with appropriate locks held only. The tail item is | |
1498 | * returned or %NULL if the list is empty. | |
1499 | */ | |
7965bd4d | 1500 | struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); |
1da177e4 LT |
1501 | static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) |
1502 | { | |
1503 | struct sk_buff *skb = skb_peek_tail(list); | |
1504 | if (skb) | |
1505 | __skb_unlink(skb, list); | |
1506 | return skb; | |
1507 | } | |
1508 | ||
1509 | ||
bdcc0924 | 1510 | static inline bool skb_is_nonlinear(const struct sk_buff *skb) |
1da177e4 LT |
1511 | { |
1512 | return skb->data_len; | |
1513 | } | |
1514 | ||
1515 | static inline unsigned int skb_headlen(const struct sk_buff *skb) | |
1516 | { | |
1517 | return skb->len - skb->data_len; | |
1518 | } | |
1519 | ||
1520 | static inline int skb_pagelen(const struct sk_buff *skb) | |
1521 | { | |
1522 | int i, len = 0; | |
1523 | ||
1524 | for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) | |
9e903e08 | 1525 | len += skb_frag_size(&skb_shinfo(skb)->frags[i]); |
1da177e4 LT |
1526 | return len + skb_headlen(skb); |
1527 | } | |
1528 | ||
131ea667 IC |
1529 | /** |
1530 | * __skb_fill_page_desc - initialise a paged fragment in an skb | |
1531 | * @skb: buffer containing fragment to be initialised | |
1532 | * @i: paged fragment index to initialise | |
1533 | * @page: the page to use for this fragment | |
1534 | * @off: the offset to the data with @page | |
1535 | * @size: the length of the data | |
1536 | * | |
1537 | * Initialises the @i'th fragment of @skb to point to &size bytes at | |
1538 | * offset @off within @page. | |
1539 | * | |
1540 | * Does not take any additional reference on the fragment. | |
1541 | */ | |
1542 | static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, | |
1543 | struct page *page, int off, int size) | |
1da177e4 LT |
1544 | { |
1545 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; | |
1546 | ||
c48a11c7 MG |
1547 | /* |
1548 | * Propagate page->pfmemalloc to the skb if we can. The problem is | |
1549 | * that not all callers have unique ownership of the page. If | |
1550 | * pfmemalloc is set, we check the mapping as a mapping implies | |
1551 | * page->index is set (index and pfmemalloc share space). | |
1552 | * If it's a valid mapping, we cannot use page->pfmemalloc but we | |
1553 | * do not lose pfmemalloc information as the pages would not be | |
1554 | * allocated using __GFP_MEMALLOC. | |
1555 | */ | |
a8605c60 | 1556 | frag->page.p = page; |
1da177e4 | 1557 | frag->page_offset = off; |
9e903e08 | 1558 | skb_frag_size_set(frag, size); |
cca7af38 PE |
1559 | |
1560 | page = compound_head(page); | |
1561 | if (page->pfmemalloc && !page->mapping) | |
1562 | skb->pfmemalloc = true; | |
131ea667 IC |
1563 | } |
1564 | ||
1565 | /** | |
1566 | * skb_fill_page_desc - initialise a paged fragment in an skb | |
1567 | * @skb: buffer containing fragment to be initialised | |
1568 | * @i: paged fragment index to initialise | |
1569 | * @page: the page to use for this fragment | |
1570 | * @off: the offset to the data with @page | |
1571 | * @size: the length of the data | |
1572 | * | |
1573 | * As per __skb_fill_page_desc() -- initialises the @i'th fragment of | |
bc32383c | 1574 | * @skb to point to @size bytes at offset @off within @page. In |
131ea667 IC |
1575 | * addition updates @skb such that @i is the last fragment. |
1576 | * | |
1577 | * Does not take any additional reference on the fragment. | |
1578 | */ | |
1579 | static inline void skb_fill_page_desc(struct sk_buff *skb, int i, | |
1580 | struct page *page, int off, int size) | |
1581 | { | |
1582 | __skb_fill_page_desc(skb, i, page, off, size); | |
1da177e4 LT |
1583 | skb_shinfo(skb)->nr_frags = i + 1; |
1584 | } | |
1585 | ||
7965bd4d JP |
1586 | void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, |
1587 | int size, unsigned int truesize); | |
654bed16 | 1588 | |
f8e617e1 JW |
1589 | void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, |
1590 | unsigned int truesize); | |
1591 | ||
1da177e4 | 1592 | #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) |
21dc3301 | 1593 | #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb)) |
1da177e4 LT |
1594 | #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) |
1595 | ||
27a884dc ACM |
1596 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
1597 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
1598 | { | |
1599 | return skb->head + skb->tail; | |
1600 | } | |
1601 | ||
1602 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
1603 | { | |
1604 | skb->tail = skb->data - skb->head; | |
1605 | } | |
1606 | ||
1607 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
1608 | { | |
1609 | skb_reset_tail_pointer(skb); | |
1610 | skb->tail += offset; | |
1611 | } | |
7cc46190 | 1612 | |
27a884dc ACM |
1613 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ |
1614 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
1615 | { | |
1616 | return skb->tail; | |
1617 | } | |
1618 | ||
1619 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
1620 | { | |
1621 | skb->tail = skb->data; | |
1622 | } | |
1623 | ||
1624 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
1625 | { | |
1626 | skb->tail = skb->data + offset; | |
1627 | } | |
4305b541 | 1628 | |
27a884dc ACM |
1629 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ |
1630 | ||
1da177e4 LT |
1631 | /* |
1632 | * Add data to an sk_buff | |
1633 | */ | |
0c7ddf36 | 1634 | unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len); |
7965bd4d | 1635 | unsigned char *skb_put(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1636 | static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) |
1637 | { | |
27a884dc | 1638 | unsigned char *tmp = skb_tail_pointer(skb); |
1da177e4 LT |
1639 | SKB_LINEAR_ASSERT(skb); |
1640 | skb->tail += len; | |
1641 | skb->len += len; | |
1642 | return tmp; | |
1643 | } | |
1644 | ||
7965bd4d | 1645 | unsigned char *skb_push(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1646 | static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) |
1647 | { | |
1648 | skb->data -= len; | |
1649 | skb->len += len; | |
1650 | return skb->data; | |
1651 | } | |
1652 | ||
7965bd4d | 1653 | unsigned char *skb_pull(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1654 | static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) |
1655 | { | |
1656 | skb->len -= len; | |
1657 | BUG_ON(skb->len < skb->data_len); | |
1658 | return skb->data += len; | |
1659 | } | |
1660 | ||
47d29646 DM |
1661 | static inline unsigned char *skb_pull_inline(struct sk_buff *skb, unsigned int len) |
1662 | { | |
1663 | return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); | |
1664 | } | |
1665 | ||
7965bd4d | 1666 | unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); |
1da177e4 LT |
1667 | |
1668 | static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) | |
1669 | { | |
1670 | if (len > skb_headlen(skb) && | |
987c402a | 1671 | !__pskb_pull_tail(skb, len - skb_headlen(skb))) |
1da177e4 LT |
1672 | return NULL; |
1673 | skb->len -= len; | |
1674 | return skb->data += len; | |
1675 | } | |
1676 | ||
1677 | static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) | |
1678 | { | |
1679 | return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); | |
1680 | } | |
1681 | ||
1682 | static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) | |
1683 | { | |
1684 | if (likely(len <= skb_headlen(skb))) | |
1685 | return 1; | |
1686 | if (unlikely(len > skb->len)) | |
1687 | return 0; | |
987c402a | 1688 | return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL; |
1da177e4 LT |
1689 | } |
1690 | ||
1691 | /** | |
1692 | * skb_headroom - bytes at buffer head | |
1693 | * @skb: buffer to check | |
1694 | * | |
1695 | * Return the number of bytes of free space at the head of an &sk_buff. | |
1696 | */ | |
c2636b4d | 1697 | static inline unsigned int skb_headroom(const struct sk_buff *skb) |
1da177e4 LT |
1698 | { |
1699 | return skb->data - skb->head; | |
1700 | } | |
1701 | ||
1702 | /** | |
1703 | * skb_tailroom - bytes at buffer end | |
1704 | * @skb: buffer to check | |
1705 | * | |
1706 | * Return the number of bytes of free space at the tail of an sk_buff | |
1707 | */ | |
1708 | static inline int skb_tailroom(const struct sk_buff *skb) | |
1709 | { | |
4305b541 | 1710 | return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; |
1da177e4 LT |
1711 | } |
1712 | ||
a21d4572 ED |
1713 | /** |
1714 | * skb_availroom - bytes at buffer end | |
1715 | * @skb: buffer to check | |
1716 | * | |
1717 | * Return the number of bytes of free space at the tail of an sk_buff | |
1718 | * allocated by sk_stream_alloc() | |
1719 | */ | |
1720 | static inline int skb_availroom(const struct sk_buff *skb) | |
1721 | { | |
16fad69c ED |
1722 | if (skb_is_nonlinear(skb)) |
1723 | return 0; | |
1724 | ||
1725 | return skb->end - skb->tail - skb->reserved_tailroom; | |
a21d4572 ED |
1726 | } |
1727 | ||
1da177e4 LT |
1728 | /** |
1729 | * skb_reserve - adjust headroom | |
1730 | * @skb: buffer to alter | |
1731 | * @len: bytes to move | |
1732 | * | |
1733 | * Increase the headroom of an empty &sk_buff by reducing the tail | |
1734 | * room. This is only allowed for an empty buffer. | |
1735 | */ | |
8243126c | 1736 | static inline void skb_reserve(struct sk_buff *skb, int len) |
1da177e4 LT |
1737 | { |
1738 | skb->data += len; | |
1739 | skb->tail += len; | |
1740 | } | |
1741 | ||
6a674e9c JG |
1742 | static inline void skb_reset_inner_headers(struct sk_buff *skb) |
1743 | { | |
aefbd2b3 | 1744 | skb->inner_mac_header = skb->mac_header; |
6a674e9c JG |
1745 | skb->inner_network_header = skb->network_header; |
1746 | skb->inner_transport_header = skb->transport_header; | |
1747 | } | |
1748 | ||
0b5c9db1 JP |
1749 | static inline void skb_reset_mac_len(struct sk_buff *skb) |
1750 | { | |
1751 | skb->mac_len = skb->network_header - skb->mac_header; | |
1752 | } | |
1753 | ||
6a674e9c JG |
1754 | static inline unsigned char *skb_inner_transport_header(const struct sk_buff |
1755 | *skb) | |
1756 | { | |
1757 | return skb->head + skb->inner_transport_header; | |
1758 | } | |
1759 | ||
1760 | static inline void skb_reset_inner_transport_header(struct sk_buff *skb) | |
1761 | { | |
1762 | skb->inner_transport_header = skb->data - skb->head; | |
1763 | } | |
1764 | ||
1765 | static inline void skb_set_inner_transport_header(struct sk_buff *skb, | |
1766 | const int offset) | |
1767 | { | |
1768 | skb_reset_inner_transport_header(skb); | |
1769 | skb->inner_transport_header += offset; | |
1770 | } | |
1771 | ||
1772 | static inline unsigned char *skb_inner_network_header(const struct sk_buff *skb) | |
1773 | { | |
1774 | return skb->head + skb->inner_network_header; | |
1775 | } | |
1776 | ||
1777 | static inline void skb_reset_inner_network_header(struct sk_buff *skb) | |
1778 | { | |
1779 | skb->inner_network_header = skb->data - skb->head; | |
1780 | } | |
1781 | ||
1782 | static inline void skb_set_inner_network_header(struct sk_buff *skb, | |
1783 | const int offset) | |
1784 | { | |
1785 | skb_reset_inner_network_header(skb); | |
1786 | skb->inner_network_header += offset; | |
1787 | } | |
1788 | ||
aefbd2b3 PS |
1789 | static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb) |
1790 | { | |
1791 | return skb->head + skb->inner_mac_header; | |
1792 | } | |
1793 | ||
1794 | static inline void skb_reset_inner_mac_header(struct sk_buff *skb) | |
1795 | { | |
1796 | skb->inner_mac_header = skb->data - skb->head; | |
1797 | } | |
1798 | ||
1799 | static inline void skb_set_inner_mac_header(struct sk_buff *skb, | |
1800 | const int offset) | |
1801 | { | |
1802 | skb_reset_inner_mac_header(skb); | |
1803 | skb->inner_mac_header += offset; | |
1804 | } | |
fda55eca ED |
1805 | static inline bool skb_transport_header_was_set(const struct sk_buff *skb) |
1806 | { | |
35d04610 | 1807 | return skb->transport_header != (typeof(skb->transport_header))~0U; |
fda55eca ED |
1808 | } |
1809 | ||
9c70220b ACM |
1810 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) |
1811 | { | |
2e07fa9c | 1812 | return skb->head + skb->transport_header; |
9c70220b ACM |
1813 | } |
1814 | ||
badff6d0 ACM |
1815 | static inline void skb_reset_transport_header(struct sk_buff *skb) |
1816 | { | |
2e07fa9c | 1817 | skb->transport_header = skb->data - skb->head; |
badff6d0 ACM |
1818 | } |
1819 | ||
967b05f6 ACM |
1820 | static inline void skb_set_transport_header(struct sk_buff *skb, |
1821 | const int offset) | |
1822 | { | |
2e07fa9c ACM |
1823 | skb_reset_transport_header(skb); |
1824 | skb->transport_header += offset; | |
ea2ae17d ACM |
1825 | } |
1826 | ||
d56f90a7 ACM |
1827 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) |
1828 | { | |
2e07fa9c | 1829 | return skb->head + skb->network_header; |
d56f90a7 ACM |
1830 | } |
1831 | ||
c1d2bbe1 ACM |
1832 | static inline void skb_reset_network_header(struct sk_buff *skb) |
1833 | { | |
2e07fa9c | 1834 | skb->network_header = skb->data - skb->head; |
c1d2bbe1 ACM |
1835 | } |
1836 | ||
c14d2450 ACM |
1837 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) |
1838 | { | |
2e07fa9c ACM |
1839 | skb_reset_network_header(skb); |
1840 | skb->network_header += offset; | |
c14d2450 ACM |
1841 | } |
1842 | ||
2e07fa9c | 1843 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) |
bbe735e4 | 1844 | { |
2e07fa9c | 1845 | return skb->head + skb->mac_header; |
bbe735e4 ACM |
1846 | } |
1847 | ||
2e07fa9c | 1848 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) |
cfe1fc77 | 1849 | { |
35d04610 | 1850 | return skb->mac_header != (typeof(skb->mac_header))~0U; |
2e07fa9c ACM |
1851 | } |
1852 | ||
1853 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1854 | { | |
1855 | skb->mac_header = skb->data - skb->head; | |
1856 | } | |
1857 | ||
1858 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1859 | { | |
1860 | skb_reset_mac_header(skb); | |
1861 | skb->mac_header += offset; | |
1862 | } | |
1863 | ||
0e3da5bb TT |
1864 | static inline void skb_pop_mac_header(struct sk_buff *skb) |
1865 | { | |
1866 | skb->mac_header = skb->network_header; | |
1867 | } | |
1868 | ||
fbbdb8f0 YX |
1869 | static inline void skb_probe_transport_header(struct sk_buff *skb, |
1870 | const int offset_hint) | |
1871 | { | |
1872 | struct flow_keys keys; | |
1873 | ||
1874 | if (skb_transport_header_was_set(skb)) | |
1875 | return; | |
1876 | else if (skb_flow_dissect(skb, &keys)) | |
1877 | skb_set_transport_header(skb, keys.thoff); | |
1878 | else | |
1879 | skb_set_transport_header(skb, offset_hint); | |
1880 | } | |
1881 | ||
03606895 ED |
1882 | static inline void skb_mac_header_rebuild(struct sk_buff *skb) |
1883 | { | |
1884 | if (skb_mac_header_was_set(skb)) { | |
1885 | const unsigned char *old_mac = skb_mac_header(skb); | |
1886 | ||
1887 | skb_set_mac_header(skb, -skb->mac_len); | |
1888 | memmove(skb_mac_header(skb), old_mac, skb->mac_len); | |
1889 | } | |
1890 | } | |
1891 | ||
04fb451e MM |
1892 | static inline int skb_checksum_start_offset(const struct sk_buff *skb) |
1893 | { | |
1894 | return skb->csum_start - skb_headroom(skb); | |
1895 | } | |
1896 | ||
2e07fa9c ACM |
1897 | static inline int skb_transport_offset(const struct sk_buff *skb) |
1898 | { | |
1899 | return skb_transport_header(skb) - skb->data; | |
1900 | } | |
1901 | ||
1902 | static inline u32 skb_network_header_len(const struct sk_buff *skb) | |
1903 | { | |
1904 | return skb->transport_header - skb->network_header; | |
1905 | } | |
1906 | ||
6a674e9c JG |
1907 | static inline u32 skb_inner_network_header_len(const struct sk_buff *skb) |
1908 | { | |
1909 | return skb->inner_transport_header - skb->inner_network_header; | |
1910 | } | |
1911 | ||
2e07fa9c ACM |
1912 | static inline int skb_network_offset(const struct sk_buff *skb) |
1913 | { | |
1914 | return skb_network_header(skb) - skb->data; | |
1915 | } | |
48d49d0c | 1916 | |
6a674e9c JG |
1917 | static inline int skb_inner_network_offset(const struct sk_buff *skb) |
1918 | { | |
1919 | return skb_inner_network_header(skb) - skb->data; | |
1920 | } | |
1921 | ||
f9599ce1 CG |
1922 | static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len) |
1923 | { | |
1924 | return pskb_may_pull(skb, skb_network_offset(skb) + len); | |
1925 | } | |
1926 | ||
1da177e4 LT |
1927 | /* |
1928 | * CPUs often take a performance hit when accessing unaligned memory | |
1929 | * locations. The actual performance hit varies, it can be small if the | |
1930 | * hardware handles it or large if we have to take an exception and fix it | |
1931 | * in software. | |
1932 | * | |
1933 | * Since an ethernet header is 14 bytes network drivers often end up with | |
1934 | * the IP header at an unaligned offset. The IP header can be aligned by | |
1935 | * shifting the start of the packet by 2 bytes. Drivers should do this | |
1936 | * with: | |
1937 | * | |
8660c124 | 1938 | * skb_reserve(skb, NET_IP_ALIGN); |
1da177e4 LT |
1939 | * |
1940 | * The downside to this alignment of the IP header is that the DMA is now | |
1941 | * unaligned. On some architectures the cost of an unaligned DMA is high | |
1942 | * and this cost outweighs the gains made by aligning the IP header. | |
8660c124 | 1943 | * |
1da177e4 LT |
1944 | * Since this trade off varies between architectures, we allow NET_IP_ALIGN |
1945 | * to be overridden. | |
1946 | */ | |
1947 | #ifndef NET_IP_ALIGN | |
1948 | #define NET_IP_ALIGN 2 | |
1949 | #endif | |
1950 | ||
025be81e AB |
1951 | /* |
1952 | * The networking layer reserves some headroom in skb data (via | |
1953 | * dev_alloc_skb). This is used to avoid having to reallocate skb data when | |
1954 | * the header has to grow. In the default case, if the header has to grow | |
d6301d3d | 1955 | * 32 bytes or less we avoid the reallocation. |
025be81e AB |
1956 | * |
1957 | * Unfortunately this headroom changes the DMA alignment of the resulting | |
1958 | * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive | |
1959 | * on some architectures. An architecture can override this value, | |
1960 | * perhaps setting it to a cacheline in size (since that will maintain | |
1961 | * cacheline alignment of the DMA). It must be a power of 2. | |
1962 | * | |
d6301d3d | 1963 | * Various parts of the networking layer expect at least 32 bytes of |
025be81e | 1964 | * headroom, you should not reduce this. |
5933dd2f ED |
1965 | * |
1966 | * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS) | |
1967 | * to reduce average number of cache lines per packet. | |
1968 | * get_rps_cpus() for example only access one 64 bytes aligned block : | |
18e8c134 | 1969 | * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8) |
025be81e AB |
1970 | */ |
1971 | #ifndef NET_SKB_PAD | |
5933dd2f | 1972 | #define NET_SKB_PAD max(32, L1_CACHE_BYTES) |
025be81e AB |
1973 | #endif |
1974 | ||
7965bd4d | 1975 | int ___pskb_trim(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1976 | |
1977 | static inline void __skb_trim(struct sk_buff *skb, unsigned int len) | |
1978 | { | |
c4264f27 | 1979 | if (unlikely(skb_is_nonlinear(skb))) { |
3cc0e873 HX |
1980 | WARN_ON(1); |
1981 | return; | |
1982 | } | |
27a884dc ACM |
1983 | skb->len = len; |
1984 | skb_set_tail_pointer(skb, len); | |
1da177e4 LT |
1985 | } |
1986 | ||
7965bd4d | 1987 | void skb_trim(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1988 | |
1989 | static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) | |
1990 | { | |
3cc0e873 HX |
1991 | if (skb->data_len) |
1992 | return ___pskb_trim(skb, len); | |
1993 | __skb_trim(skb, len); | |
1994 | return 0; | |
1da177e4 LT |
1995 | } |
1996 | ||
1997 | static inline int pskb_trim(struct sk_buff *skb, unsigned int len) | |
1998 | { | |
1999 | return (len < skb->len) ? __pskb_trim(skb, len) : 0; | |
2000 | } | |
2001 | ||
e9fa4f7b HX |
2002 | /** |
2003 | * pskb_trim_unique - remove end from a paged unique (not cloned) buffer | |
2004 | * @skb: buffer to alter | |
2005 | * @len: new length | |
2006 | * | |
2007 | * This is identical to pskb_trim except that the caller knows that | |
2008 | * the skb is not cloned so we should never get an error due to out- | |
2009 | * of-memory. | |
2010 | */ | |
2011 | static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) | |
2012 | { | |
2013 | int err = pskb_trim(skb, len); | |
2014 | BUG_ON(err); | |
2015 | } | |
2016 | ||
1da177e4 LT |
2017 | /** |
2018 | * skb_orphan - orphan a buffer | |
2019 | * @skb: buffer to orphan | |
2020 | * | |
2021 | * If a buffer currently has an owner then we call the owner's | |
2022 | * destructor function and make the @skb unowned. The buffer continues | |
2023 | * to exist but is no longer charged to its former owner. | |
2024 | */ | |
2025 | static inline void skb_orphan(struct sk_buff *skb) | |
2026 | { | |
c34a7612 | 2027 | if (skb->destructor) { |
1da177e4 | 2028 | skb->destructor(skb); |
c34a7612 ED |
2029 | skb->destructor = NULL; |
2030 | skb->sk = NULL; | |
376c7311 ED |
2031 | } else { |
2032 | BUG_ON(skb->sk); | |
c34a7612 | 2033 | } |
1da177e4 LT |
2034 | } |
2035 | ||
a353e0ce MT |
2036 | /** |
2037 | * skb_orphan_frags - orphan the frags contained in a buffer | |
2038 | * @skb: buffer to orphan frags from | |
2039 | * @gfp_mask: allocation mask for replacement pages | |
2040 | * | |
2041 | * For each frag in the SKB which needs a destructor (i.e. has an | |
2042 | * owner) create a copy of that frag and release the original | |
2043 | * page by calling the destructor. | |
2044 | */ | |
2045 | static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask) | |
2046 | { | |
2047 | if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY))) | |
2048 | return 0; | |
2049 | return skb_copy_ubufs(skb, gfp_mask); | |
2050 | } | |
2051 | ||
1da177e4 LT |
2052 | /** |
2053 | * __skb_queue_purge - empty a list | |
2054 | * @list: list to empty | |
2055 | * | |
2056 | * Delete all buffers on an &sk_buff list. Each buffer is removed from | |
2057 | * the list and one reference dropped. This function does not take the | |
2058 | * list lock and the caller must hold the relevant locks to use it. | |
2059 | */ | |
7965bd4d | 2060 | void skb_queue_purge(struct sk_buff_head *list); |
1da177e4 LT |
2061 | static inline void __skb_queue_purge(struct sk_buff_head *list) |
2062 | { | |
2063 | struct sk_buff *skb; | |
2064 | while ((skb = __skb_dequeue(list)) != NULL) | |
2065 | kfree_skb(skb); | |
2066 | } | |
2067 | ||
e5e67305 AD |
2068 | #define NETDEV_FRAG_PAGE_MAX_ORDER get_order(32768) |
2069 | #define NETDEV_FRAG_PAGE_MAX_SIZE (PAGE_SIZE << NETDEV_FRAG_PAGE_MAX_ORDER) | |
2070 | #define NETDEV_PAGECNT_MAX_BIAS NETDEV_FRAG_PAGE_MAX_SIZE | |
2071 | ||
7965bd4d | 2072 | void *netdev_alloc_frag(unsigned int fragsz); |
1da177e4 | 2073 | |
7965bd4d JP |
2074 | struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length, |
2075 | gfp_t gfp_mask); | |
8af27456 CH |
2076 | |
2077 | /** | |
2078 | * netdev_alloc_skb - allocate an skbuff for rx on a specific device | |
2079 | * @dev: network device to receive on | |
2080 | * @length: length to allocate | |
2081 | * | |
2082 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
2083 | * buffer has unspecified headroom built in. Users should allocate | |
2084 | * the headroom they think they need without accounting for the | |
2085 | * built in space. The built in space is used for optimisations. | |
2086 | * | |
2087 | * %NULL is returned if there is no free memory. Although this function | |
2088 | * allocates memory it can be called from an interrupt. | |
2089 | */ | |
2090 | static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, | |
6f532612 | 2091 | unsigned int length) |
8af27456 CH |
2092 | { |
2093 | return __netdev_alloc_skb(dev, length, GFP_ATOMIC); | |
2094 | } | |
2095 | ||
6f532612 ED |
2096 | /* legacy helper around __netdev_alloc_skb() */ |
2097 | static inline struct sk_buff *__dev_alloc_skb(unsigned int length, | |
2098 | gfp_t gfp_mask) | |
2099 | { | |
2100 | return __netdev_alloc_skb(NULL, length, gfp_mask); | |
2101 | } | |
2102 | ||
2103 | /* legacy helper around netdev_alloc_skb() */ | |
2104 | static inline struct sk_buff *dev_alloc_skb(unsigned int length) | |
2105 | { | |
2106 | return netdev_alloc_skb(NULL, length); | |
2107 | } | |
2108 | ||
2109 | ||
4915a0de ED |
2110 | static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, |
2111 | unsigned int length, gfp_t gfp) | |
61321bbd | 2112 | { |
4915a0de | 2113 | struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); |
61321bbd ED |
2114 | |
2115 | if (NET_IP_ALIGN && skb) | |
2116 | skb_reserve(skb, NET_IP_ALIGN); | |
2117 | return skb; | |
2118 | } | |
2119 | ||
4915a0de ED |
2120 | static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, |
2121 | unsigned int length) | |
2122 | { | |
2123 | return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC); | |
2124 | } | |
2125 | ||
bc6fc9fa FF |
2126 | /** |
2127 | * __skb_alloc_pages - allocate pages for ps-rx on a skb and preserve pfmemalloc data | |
0614002b MG |
2128 | * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX |
2129 | * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used | |
2130 | * @order: size of the allocation | |
2131 | * | |
2132 | * Allocate a new page. | |
2133 | * | |
2134 | * %NULL is returned if there is no free memory. | |
2135 | */ | |
2136 | static inline struct page *__skb_alloc_pages(gfp_t gfp_mask, | |
2137 | struct sk_buff *skb, | |
2138 | unsigned int order) | |
2139 | { | |
2140 | struct page *page; | |
2141 | ||
2142 | gfp_mask |= __GFP_COLD; | |
2143 | ||
2144 | if (!(gfp_mask & __GFP_NOMEMALLOC)) | |
2145 | gfp_mask |= __GFP_MEMALLOC; | |
2146 | ||
2147 | page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, order); | |
2148 | if (skb && page && page->pfmemalloc) | |
2149 | skb->pfmemalloc = true; | |
2150 | ||
2151 | return page; | |
2152 | } | |
2153 | ||
2154 | /** | |
2155 | * __skb_alloc_page - allocate a page for ps-rx for a given skb and preserve pfmemalloc data | |
2156 | * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX | |
2157 | * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used | |
2158 | * | |
2159 | * Allocate a new page. | |
2160 | * | |
2161 | * %NULL is returned if there is no free memory. | |
2162 | */ | |
2163 | static inline struct page *__skb_alloc_page(gfp_t gfp_mask, | |
2164 | struct sk_buff *skb) | |
2165 | { | |
2166 | return __skb_alloc_pages(gfp_mask, skb, 0); | |
2167 | } | |
2168 | ||
2169 | /** | |
2170 | * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page | |
2171 | * @page: The page that was allocated from skb_alloc_page | |
2172 | * @skb: The skb that may need pfmemalloc set | |
2173 | */ | |
2174 | static inline void skb_propagate_pfmemalloc(struct page *page, | |
2175 | struct sk_buff *skb) | |
2176 | { | |
2177 | if (page && page->pfmemalloc) | |
2178 | skb->pfmemalloc = true; | |
2179 | } | |
2180 | ||
131ea667 | 2181 | /** |
e227867f | 2182 | * skb_frag_page - retrieve the page referred to by a paged fragment |
131ea667 IC |
2183 | * @frag: the paged fragment |
2184 | * | |
2185 | * Returns the &struct page associated with @frag. | |
2186 | */ | |
2187 | static inline struct page *skb_frag_page(const skb_frag_t *frag) | |
2188 | { | |
a8605c60 | 2189 | return frag->page.p; |
131ea667 IC |
2190 | } |
2191 | ||
2192 | /** | |
2193 | * __skb_frag_ref - take an addition reference on a paged fragment. | |
2194 | * @frag: the paged fragment | |
2195 | * | |
2196 | * Takes an additional reference on the paged fragment @frag. | |
2197 | */ | |
2198 | static inline void __skb_frag_ref(skb_frag_t *frag) | |
2199 | { | |
2200 | get_page(skb_frag_page(frag)); | |
2201 | } | |
2202 | ||
2203 | /** | |
2204 | * skb_frag_ref - take an addition reference on a paged fragment of an skb. | |
2205 | * @skb: the buffer | |
2206 | * @f: the fragment offset. | |
2207 | * | |
2208 | * Takes an additional reference on the @f'th paged fragment of @skb. | |
2209 | */ | |
2210 | static inline void skb_frag_ref(struct sk_buff *skb, int f) | |
2211 | { | |
2212 | __skb_frag_ref(&skb_shinfo(skb)->frags[f]); | |
2213 | } | |
2214 | ||
2215 | /** | |
2216 | * __skb_frag_unref - release a reference on a paged fragment. | |
2217 | * @frag: the paged fragment | |
2218 | * | |
2219 | * Releases a reference on the paged fragment @frag. | |
2220 | */ | |
2221 | static inline void __skb_frag_unref(skb_frag_t *frag) | |
2222 | { | |
2223 | put_page(skb_frag_page(frag)); | |
2224 | } | |
2225 | ||
2226 | /** | |
2227 | * skb_frag_unref - release a reference on a paged fragment of an skb. | |
2228 | * @skb: the buffer | |
2229 | * @f: the fragment offset | |
2230 | * | |
2231 | * Releases a reference on the @f'th paged fragment of @skb. | |
2232 | */ | |
2233 | static inline void skb_frag_unref(struct sk_buff *skb, int f) | |
2234 | { | |
2235 | __skb_frag_unref(&skb_shinfo(skb)->frags[f]); | |
2236 | } | |
2237 | ||
2238 | /** | |
2239 | * skb_frag_address - gets the address of the data contained in a paged fragment | |
2240 | * @frag: the paged fragment buffer | |
2241 | * | |
2242 | * Returns the address of the data within @frag. The page must already | |
2243 | * be mapped. | |
2244 | */ | |
2245 | static inline void *skb_frag_address(const skb_frag_t *frag) | |
2246 | { | |
2247 | return page_address(skb_frag_page(frag)) + frag->page_offset; | |
2248 | } | |
2249 | ||
2250 | /** | |
2251 | * skb_frag_address_safe - gets the address of the data contained in a paged fragment | |
2252 | * @frag: the paged fragment buffer | |
2253 | * | |
2254 | * Returns the address of the data within @frag. Checks that the page | |
2255 | * is mapped and returns %NULL otherwise. | |
2256 | */ | |
2257 | static inline void *skb_frag_address_safe(const skb_frag_t *frag) | |
2258 | { | |
2259 | void *ptr = page_address(skb_frag_page(frag)); | |
2260 | if (unlikely(!ptr)) | |
2261 | return NULL; | |
2262 | ||
2263 | return ptr + frag->page_offset; | |
2264 | } | |
2265 | ||
2266 | /** | |
2267 | * __skb_frag_set_page - sets the page contained in a paged fragment | |
2268 | * @frag: the paged fragment | |
2269 | * @page: the page to set | |
2270 | * | |
2271 | * Sets the fragment @frag to contain @page. | |
2272 | */ | |
2273 | static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page) | |
2274 | { | |
a8605c60 | 2275 | frag->page.p = page; |
131ea667 IC |
2276 | } |
2277 | ||
2278 | /** | |
2279 | * skb_frag_set_page - sets the page contained in a paged fragment of an skb | |
2280 | * @skb: the buffer | |
2281 | * @f: the fragment offset | |
2282 | * @page: the page to set | |
2283 | * | |
2284 | * Sets the @f'th fragment of @skb to contain @page. | |
2285 | */ | |
2286 | static inline void skb_frag_set_page(struct sk_buff *skb, int f, | |
2287 | struct page *page) | |
2288 | { | |
2289 | __skb_frag_set_page(&skb_shinfo(skb)->frags[f], page); | |
2290 | } | |
2291 | ||
400dfd3a ED |
2292 | bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio); |
2293 | ||
131ea667 IC |
2294 | /** |
2295 | * skb_frag_dma_map - maps a paged fragment via the DMA API | |
f83347df | 2296 | * @dev: the device to map the fragment to |
131ea667 IC |
2297 | * @frag: the paged fragment to map |
2298 | * @offset: the offset within the fragment (starting at the | |
2299 | * fragment's own offset) | |
2300 | * @size: the number of bytes to map | |
f83347df | 2301 | * @dir: the direction of the mapping (%PCI_DMA_*) |
131ea667 IC |
2302 | * |
2303 | * Maps the page associated with @frag to @device. | |
2304 | */ | |
2305 | static inline dma_addr_t skb_frag_dma_map(struct device *dev, | |
2306 | const skb_frag_t *frag, | |
2307 | size_t offset, size_t size, | |
2308 | enum dma_data_direction dir) | |
2309 | { | |
2310 | return dma_map_page(dev, skb_frag_page(frag), | |
2311 | frag->page_offset + offset, size, dir); | |
2312 | } | |
2313 | ||
117632e6 ED |
2314 | static inline struct sk_buff *pskb_copy(struct sk_buff *skb, |
2315 | gfp_t gfp_mask) | |
2316 | { | |
2317 | return __pskb_copy(skb, skb_headroom(skb), gfp_mask); | |
2318 | } | |
2319 | ||
bad93e9d OP |
2320 | |
2321 | static inline struct sk_buff *pskb_copy_for_clone(struct sk_buff *skb, | |
2322 | gfp_t gfp_mask) | |
2323 | { | |
2324 | return __pskb_copy_fclone(skb, skb_headroom(skb), gfp_mask, true); | |
2325 | } | |
2326 | ||
2327 | ||
334a8132 PM |
2328 | /** |
2329 | * skb_clone_writable - is the header of a clone writable | |
2330 | * @skb: buffer to check | |
2331 | * @len: length up to which to write | |
2332 | * | |
2333 | * Returns true if modifying the header part of the cloned buffer | |
2334 | * does not requires the data to be copied. | |
2335 | */ | |
05bdd2f1 | 2336 | static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len) |
334a8132 PM |
2337 | { |
2338 | return !skb_header_cloned(skb) && | |
2339 | skb_headroom(skb) + len <= skb->hdr_len; | |
2340 | } | |
2341 | ||
d9cc2048 HX |
2342 | static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom, |
2343 | int cloned) | |
2344 | { | |
2345 | int delta = 0; | |
2346 | ||
d9cc2048 HX |
2347 | if (headroom > skb_headroom(skb)) |
2348 | delta = headroom - skb_headroom(skb); | |
2349 | ||
2350 | if (delta || cloned) | |
2351 | return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, | |
2352 | GFP_ATOMIC); | |
2353 | return 0; | |
2354 | } | |
2355 | ||
1da177e4 LT |
2356 | /** |
2357 | * skb_cow - copy header of skb when it is required | |
2358 | * @skb: buffer to cow | |
2359 | * @headroom: needed headroom | |
2360 | * | |
2361 | * If the skb passed lacks sufficient headroom or its data part | |
2362 | * is shared, data is reallocated. If reallocation fails, an error | |
2363 | * is returned and original skb is not changed. | |
2364 | * | |
2365 | * The result is skb with writable area skb->head...skb->tail | |
2366 | * and at least @headroom of space at head. | |
2367 | */ | |
2368 | static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) | |
2369 | { | |
d9cc2048 HX |
2370 | return __skb_cow(skb, headroom, skb_cloned(skb)); |
2371 | } | |
1da177e4 | 2372 | |
d9cc2048 HX |
2373 | /** |
2374 | * skb_cow_head - skb_cow but only making the head writable | |
2375 | * @skb: buffer to cow | |
2376 | * @headroom: needed headroom | |
2377 | * | |
2378 | * This function is identical to skb_cow except that we replace the | |
2379 | * skb_cloned check by skb_header_cloned. It should be used when | |
2380 | * you only need to push on some header and do not need to modify | |
2381 | * the data. | |
2382 | */ | |
2383 | static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom) | |
2384 | { | |
2385 | return __skb_cow(skb, headroom, skb_header_cloned(skb)); | |
1da177e4 LT |
2386 | } |
2387 | ||
2388 | /** | |
2389 | * skb_padto - pad an skbuff up to a minimal size | |
2390 | * @skb: buffer to pad | |
2391 | * @len: minimal length | |
2392 | * | |
2393 | * Pads up a buffer to ensure the trailing bytes exist and are | |
2394 | * blanked. If the buffer already contains sufficient data it | |
5b057c6b HX |
2395 | * is untouched. Otherwise it is extended. Returns zero on |
2396 | * success. The skb is freed on error. | |
1da177e4 LT |
2397 | */ |
2398 | ||
5b057c6b | 2399 | static inline int skb_padto(struct sk_buff *skb, unsigned int len) |
1da177e4 LT |
2400 | { |
2401 | unsigned int size = skb->len; | |
2402 | if (likely(size >= len)) | |
5b057c6b | 2403 | return 0; |
987c402a | 2404 | return skb_pad(skb, len - size); |
1da177e4 LT |
2405 | } |
2406 | ||
2407 | static inline int skb_add_data(struct sk_buff *skb, | |
2408 | char __user *from, int copy) | |
2409 | { | |
2410 | const int off = skb->len; | |
2411 | ||
2412 | if (skb->ip_summed == CHECKSUM_NONE) { | |
2413 | int err = 0; | |
5084205f | 2414 | __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), |
1da177e4 LT |
2415 | copy, 0, &err); |
2416 | if (!err) { | |
2417 | skb->csum = csum_block_add(skb->csum, csum, off); | |
2418 | return 0; | |
2419 | } | |
2420 | } else if (!copy_from_user(skb_put(skb, copy), from, copy)) | |
2421 | return 0; | |
2422 | ||
2423 | __skb_trim(skb, off); | |
2424 | return -EFAULT; | |
2425 | } | |
2426 | ||
38ba0a65 ED |
2427 | static inline bool skb_can_coalesce(struct sk_buff *skb, int i, |
2428 | const struct page *page, int off) | |
1da177e4 LT |
2429 | { |
2430 | if (i) { | |
9e903e08 | 2431 | const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; |
1da177e4 | 2432 | |
ea2ab693 | 2433 | return page == skb_frag_page(frag) && |
9e903e08 | 2434 | off == frag->page_offset + skb_frag_size(frag); |
1da177e4 | 2435 | } |
38ba0a65 | 2436 | return false; |
1da177e4 LT |
2437 | } |
2438 | ||
364c6bad HX |
2439 | static inline int __skb_linearize(struct sk_buff *skb) |
2440 | { | |
2441 | return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; | |
2442 | } | |
2443 | ||
1da177e4 LT |
2444 | /** |
2445 | * skb_linearize - convert paged skb to linear one | |
2446 | * @skb: buffer to linarize | |
1da177e4 LT |
2447 | * |
2448 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
2449 | * is returned and the old skb data released. | |
2450 | */ | |
364c6bad HX |
2451 | static inline int skb_linearize(struct sk_buff *skb) |
2452 | { | |
2453 | return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; | |
2454 | } | |
2455 | ||
cef401de ED |
2456 | /** |
2457 | * skb_has_shared_frag - can any frag be overwritten | |
2458 | * @skb: buffer to test | |
2459 | * | |
2460 | * Return true if the skb has at least one frag that might be modified | |
2461 | * by an external entity (as in vmsplice()/sendfile()) | |
2462 | */ | |
2463 | static inline bool skb_has_shared_frag(const struct sk_buff *skb) | |
2464 | { | |
c9af6db4 PS |
2465 | return skb_is_nonlinear(skb) && |
2466 | skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; | |
cef401de ED |
2467 | } |
2468 | ||
364c6bad HX |
2469 | /** |
2470 | * skb_linearize_cow - make sure skb is linear and writable | |
2471 | * @skb: buffer to process | |
2472 | * | |
2473 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
2474 | * is returned and the old skb data released. | |
2475 | */ | |
2476 | static inline int skb_linearize_cow(struct sk_buff *skb) | |
1da177e4 | 2477 | { |
364c6bad HX |
2478 | return skb_is_nonlinear(skb) || skb_cloned(skb) ? |
2479 | __skb_linearize(skb) : 0; | |
1da177e4 LT |
2480 | } |
2481 | ||
2482 | /** | |
2483 | * skb_postpull_rcsum - update checksum for received skb after pull | |
2484 | * @skb: buffer to update | |
2485 | * @start: start of data before pull | |
2486 | * @len: length of data pulled | |
2487 | * | |
2488 | * After doing a pull on a received packet, you need to call this to | |
84fa7933 PM |
2489 | * update the CHECKSUM_COMPLETE checksum, or set ip_summed to |
2490 | * CHECKSUM_NONE so that it can be recomputed from scratch. | |
1da177e4 LT |
2491 | */ |
2492 | ||
2493 | static inline void skb_postpull_rcsum(struct sk_buff *skb, | |
cbb042f9 | 2494 | const void *start, unsigned int len) |
1da177e4 | 2495 | { |
84fa7933 | 2496 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
2497 | skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); |
2498 | } | |
2499 | ||
cbb042f9 HX |
2500 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); |
2501 | ||
7ce5a27f DM |
2502 | /** |
2503 | * pskb_trim_rcsum - trim received skb and update checksum | |
2504 | * @skb: buffer to trim | |
2505 | * @len: new length | |
2506 | * | |
2507 | * This is exactly the same as pskb_trim except that it ensures the | |
2508 | * checksum of received packets are still valid after the operation. | |
2509 | */ | |
2510 | ||
2511 | static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) | |
2512 | { | |
2513 | if (likely(len >= skb->len)) | |
2514 | return 0; | |
2515 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
2516 | skb->ip_summed = CHECKSUM_NONE; | |
2517 | return __pskb_trim(skb, len); | |
2518 | } | |
2519 | ||
1da177e4 LT |
2520 | #define skb_queue_walk(queue, skb) \ |
2521 | for (skb = (queue)->next; \ | |
a1e4891f | 2522 | skb != (struct sk_buff *)(queue); \ |
1da177e4 LT |
2523 | skb = skb->next) |
2524 | ||
46f8914e JC |
2525 | #define skb_queue_walk_safe(queue, skb, tmp) \ |
2526 | for (skb = (queue)->next, tmp = skb->next; \ | |
2527 | skb != (struct sk_buff *)(queue); \ | |
2528 | skb = tmp, tmp = skb->next) | |
2529 | ||
1164f52a | 2530 | #define skb_queue_walk_from(queue, skb) \ |
a1e4891f | 2531 | for (; skb != (struct sk_buff *)(queue); \ |
1164f52a DM |
2532 | skb = skb->next) |
2533 | ||
2534 | #define skb_queue_walk_from_safe(queue, skb, tmp) \ | |
2535 | for (tmp = skb->next; \ | |
2536 | skb != (struct sk_buff *)(queue); \ | |
2537 | skb = tmp, tmp = skb->next) | |
2538 | ||
300ce174 SH |
2539 | #define skb_queue_reverse_walk(queue, skb) \ |
2540 | for (skb = (queue)->prev; \ | |
a1e4891f | 2541 | skb != (struct sk_buff *)(queue); \ |
300ce174 SH |
2542 | skb = skb->prev) |
2543 | ||
686a2955 DM |
2544 | #define skb_queue_reverse_walk_safe(queue, skb, tmp) \ |
2545 | for (skb = (queue)->prev, tmp = skb->prev; \ | |
2546 | skb != (struct sk_buff *)(queue); \ | |
2547 | skb = tmp, tmp = skb->prev) | |
2548 | ||
2549 | #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \ | |
2550 | for (tmp = skb->prev; \ | |
2551 | skb != (struct sk_buff *)(queue); \ | |
2552 | skb = tmp, tmp = skb->prev) | |
1da177e4 | 2553 | |
21dc3301 | 2554 | static inline bool skb_has_frag_list(const struct sk_buff *skb) |
ee039871 DM |
2555 | { |
2556 | return skb_shinfo(skb)->frag_list != NULL; | |
2557 | } | |
2558 | ||
2559 | static inline void skb_frag_list_init(struct sk_buff *skb) | |
2560 | { | |
2561 | skb_shinfo(skb)->frag_list = NULL; | |
2562 | } | |
2563 | ||
2564 | static inline void skb_frag_add_head(struct sk_buff *skb, struct sk_buff *frag) | |
2565 | { | |
2566 | frag->next = skb_shinfo(skb)->frag_list; | |
2567 | skb_shinfo(skb)->frag_list = frag; | |
2568 | } | |
2569 | ||
2570 | #define skb_walk_frags(skb, iter) \ | |
2571 | for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next) | |
2572 | ||
7965bd4d JP |
2573 | struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, |
2574 | int *peeked, int *off, int *err); | |
2575 | struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock, | |
2576 | int *err); | |
2577 | unsigned int datagram_poll(struct file *file, struct socket *sock, | |
2578 | struct poll_table_struct *wait); | |
2579 | int skb_copy_datagram_iovec(const struct sk_buff *from, int offset, | |
2580 | struct iovec *to, int size); | |
2581 | int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, int hlen, | |
2582 | struct iovec *iov); | |
2583 | int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, | |
2584 | const struct iovec *from, int from_offset, | |
2585 | int len); | |
2586 | int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *frm, | |
2587 | int offset, size_t count); | |
2588 | int skb_copy_datagram_const_iovec(const struct sk_buff *from, int offset, | |
2589 | const struct iovec *to, int to_offset, | |
2590 | int size); | |
2591 | void skb_free_datagram(struct sock *sk, struct sk_buff *skb); | |
2592 | void skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb); | |
2593 | int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags); | |
7965bd4d JP |
2594 | int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len); |
2595 | int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len); | |
2596 | __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, | |
2597 | int len, __wsum csum); | |
2598 | int skb_splice_bits(struct sk_buff *skb, unsigned int offset, | |
2599 | struct pipe_inode_info *pipe, unsigned int len, | |
2600 | unsigned int flags); | |
2601 | void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); | |
af2806f8 | 2602 | unsigned int skb_zerocopy_headlen(const struct sk_buff *from); |
36d5fe6a ZK |
2603 | int skb_zerocopy(struct sk_buff *to, struct sk_buff *from, |
2604 | int len, int hlen); | |
7965bd4d JP |
2605 | void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); |
2606 | int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen); | |
2607 | void skb_scrub_packet(struct sk_buff *skb, bool xnet); | |
de960aa9 | 2608 | unsigned int skb_gso_transport_seglen(const struct sk_buff *skb); |
7965bd4d | 2609 | struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features); |
0d5501c1 | 2610 | struct sk_buff *skb_vlan_untag(struct sk_buff *skb); |
20380731 | 2611 | |
2817a336 DB |
2612 | struct skb_checksum_ops { |
2613 | __wsum (*update)(const void *mem, int len, __wsum wsum); | |
2614 | __wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len); | |
2615 | }; | |
2616 | ||
2617 | __wsum __skb_checksum(const struct sk_buff *skb, int offset, int len, | |
2618 | __wsum csum, const struct skb_checksum_ops *ops); | |
2619 | __wsum skb_checksum(const struct sk_buff *skb, int offset, int len, | |
2620 | __wsum csum); | |
2621 | ||
690e36e7 DM |
2622 | static inline void *__skb_header_pointer(const struct sk_buff *skb, int offset, |
2623 | int len, void *data, int hlen, void *buffer) | |
1da177e4 | 2624 | { |
55820ee2 | 2625 | if (hlen - offset >= len) |
690e36e7 | 2626 | return data + offset; |
1da177e4 | 2627 | |
690e36e7 DM |
2628 | if (!skb || |
2629 | skb_copy_bits(skb, offset, buffer, len) < 0) | |
1da177e4 LT |
2630 | return NULL; |
2631 | ||
2632 | return buffer; | |
2633 | } | |
2634 | ||
690e36e7 DM |
2635 | static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, |
2636 | int len, void *buffer) | |
2637 | { | |
2638 | return __skb_header_pointer(skb, offset, len, skb->data, | |
2639 | skb_headlen(skb), buffer); | |
2640 | } | |
2641 | ||
4262e5cc DB |
2642 | /** |
2643 | * skb_needs_linearize - check if we need to linearize a given skb | |
2644 | * depending on the given device features. | |
2645 | * @skb: socket buffer to check | |
2646 | * @features: net device features | |
2647 | * | |
2648 | * Returns true if either: | |
2649 | * 1. skb has frag_list and the device doesn't support FRAGLIST, or | |
2650 | * 2. skb is fragmented and the device does not support SG. | |
2651 | */ | |
2652 | static inline bool skb_needs_linearize(struct sk_buff *skb, | |
2653 | netdev_features_t features) | |
2654 | { | |
2655 | return skb_is_nonlinear(skb) && | |
2656 | ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) || | |
2657 | (skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG))); | |
2658 | } | |
2659 | ||
d626f62b ACM |
2660 | static inline void skb_copy_from_linear_data(const struct sk_buff *skb, |
2661 | void *to, | |
2662 | const unsigned int len) | |
2663 | { | |
2664 | memcpy(to, skb->data, len); | |
2665 | } | |
2666 | ||
2667 | static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, | |
2668 | const int offset, void *to, | |
2669 | const unsigned int len) | |
2670 | { | |
2671 | memcpy(to, skb->data + offset, len); | |
2672 | } | |
2673 | ||
27d7ff46 ACM |
2674 | static inline void skb_copy_to_linear_data(struct sk_buff *skb, |
2675 | const void *from, | |
2676 | const unsigned int len) | |
2677 | { | |
2678 | memcpy(skb->data, from, len); | |
2679 | } | |
2680 | ||
2681 | static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, | |
2682 | const int offset, | |
2683 | const void *from, | |
2684 | const unsigned int len) | |
2685 | { | |
2686 | memcpy(skb->data + offset, from, len); | |
2687 | } | |
2688 | ||
7965bd4d | 2689 | void skb_init(void); |
1da177e4 | 2690 | |
ac45f602 PO |
2691 | static inline ktime_t skb_get_ktime(const struct sk_buff *skb) |
2692 | { | |
2693 | return skb->tstamp; | |
2694 | } | |
2695 | ||
a61bbcf2 PM |
2696 | /** |
2697 | * skb_get_timestamp - get timestamp from a skb | |
2698 | * @skb: skb to get stamp from | |
2699 | * @stamp: pointer to struct timeval to store stamp in | |
2700 | * | |
2701 | * Timestamps are stored in the skb as offsets to a base timestamp. | |
2702 | * This function converts the offset back to a struct timeval and stores | |
2703 | * it in stamp. | |
2704 | */ | |
ac45f602 PO |
2705 | static inline void skb_get_timestamp(const struct sk_buff *skb, |
2706 | struct timeval *stamp) | |
a61bbcf2 | 2707 | { |
b7aa0bf7 | 2708 | *stamp = ktime_to_timeval(skb->tstamp); |
a61bbcf2 PM |
2709 | } |
2710 | ||
ac45f602 PO |
2711 | static inline void skb_get_timestampns(const struct sk_buff *skb, |
2712 | struct timespec *stamp) | |
2713 | { | |
2714 | *stamp = ktime_to_timespec(skb->tstamp); | |
2715 | } | |
2716 | ||
b7aa0bf7 | 2717 | static inline void __net_timestamp(struct sk_buff *skb) |
a61bbcf2 | 2718 | { |
b7aa0bf7 | 2719 | skb->tstamp = ktime_get_real(); |
a61bbcf2 PM |
2720 | } |
2721 | ||
164891aa SH |
2722 | static inline ktime_t net_timedelta(ktime_t t) |
2723 | { | |
2724 | return ktime_sub(ktime_get_real(), t); | |
2725 | } | |
2726 | ||
b9ce204f IJ |
2727 | static inline ktime_t net_invalid_timestamp(void) |
2728 | { | |
2729 | return ktime_set(0, 0); | |
2730 | } | |
a61bbcf2 | 2731 | |
62bccb8c AD |
2732 | struct sk_buff *skb_clone_sk(struct sk_buff *skb); |
2733 | ||
c1f19b51 RC |
2734 | #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING |
2735 | ||
7965bd4d JP |
2736 | void skb_clone_tx_timestamp(struct sk_buff *skb); |
2737 | bool skb_defer_rx_timestamp(struct sk_buff *skb); | |
c1f19b51 RC |
2738 | |
2739 | #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */ | |
2740 | ||
2741 | static inline void skb_clone_tx_timestamp(struct sk_buff *skb) | |
2742 | { | |
2743 | } | |
2744 | ||
2745 | static inline bool skb_defer_rx_timestamp(struct sk_buff *skb) | |
2746 | { | |
2747 | return false; | |
2748 | } | |
2749 | ||
2750 | #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */ | |
2751 | ||
2752 | /** | |
2753 | * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps | |
2754 | * | |
da92b194 RC |
2755 | * PHY drivers may accept clones of transmitted packets for |
2756 | * timestamping via their phy_driver.txtstamp method. These drivers | |
2757 | * must call this function to return the skb back to the stack, with | |
2758 | * or without a timestamp. | |
2759 | * | |
c1f19b51 | 2760 | * @skb: clone of the the original outgoing packet |
da92b194 | 2761 | * @hwtstamps: hardware time stamps, may be NULL if not available |
c1f19b51 RC |
2762 | * |
2763 | */ | |
2764 | void skb_complete_tx_timestamp(struct sk_buff *skb, | |
2765 | struct skb_shared_hwtstamps *hwtstamps); | |
2766 | ||
e7fd2885 WB |
2767 | void __skb_tstamp_tx(struct sk_buff *orig_skb, |
2768 | struct skb_shared_hwtstamps *hwtstamps, | |
2769 | struct sock *sk, int tstype); | |
2770 | ||
ac45f602 PO |
2771 | /** |
2772 | * skb_tstamp_tx - queue clone of skb with send time stamps | |
2773 | * @orig_skb: the original outgoing packet | |
2774 | * @hwtstamps: hardware time stamps, may be NULL if not available | |
2775 | * | |
2776 | * If the skb has a socket associated, then this function clones the | |
2777 | * skb (thus sharing the actual data and optional structures), stores | |
2778 | * the optional hardware time stamping information (if non NULL) or | |
2779 | * generates a software time stamp (otherwise), then queues the clone | |
2780 | * to the error queue of the socket. Errors are silently ignored. | |
2781 | */ | |
7965bd4d JP |
2782 | void skb_tstamp_tx(struct sk_buff *orig_skb, |
2783 | struct skb_shared_hwtstamps *hwtstamps); | |
ac45f602 | 2784 | |
4507a715 RC |
2785 | static inline void sw_tx_timestamp(struct sk_buff *skb) |
2786 | { | |
2244d07b OH |
2787 | if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP && |
2788 | !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) | |
4507a715 RC |
2789 | skb_tstamp_tx(skb, NULL); |
2790 | } | |
2791 | ||
2792 | /** | |
2793 | * skb_tx_timestamp() - Driver hook for transmit timestamping | |
2794 | * | |
2795 | * Ethernet MAC Drivers should call this function in their hard_xmit() | |
4ff75b7c | 2796 | * function immediately before giving the sk_buff to the MAC hardware. |
4507a715 | 2797 | * |
73409f3b DM |
2798 | * Specifically, one should make absolutely sure that this function is |
2799 | * called before TX completion of this packet can trigger. Otherwise | |
2800 | * the packet could potentially already be freed. | |
2801 | * | |
4507a715 RC |
2802 | * @skb: A socket buffer. |
2803 | */ | |
2804 | static inline void skb_tx_timestamp(struct sk_buff *skb) | |
2805 | { | |
c1f19b51 | 2806 | skb_clone_tx_timestamp(skb); |
4507a715 RC |
2807 | sw_tx_timestamp(skb); |
2808 | } | |
2809 | ||
6e3e939f JB |
2810 | /** |
2811 | * skb_complete_wifi_ack - deliver skb with wifi status | |
2812 | * | |
2813 | * @skb: the original outgoing packet | |
2814 | * @acked: ack status | |
2815 | * | |
2816 | */ | |
2817 | void skb_complete_wifi_ack(struct sk_buff *skb, bool acked); | |
2818 | ||
7965bd4d JP |
2819 | __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); |
2820 | __sum16 __skb_checksum_complete(struct sk_buff *skb); | |
fb286bb2 | 2821 | |
60476372 HX |
2822 | static inline int skb_csum_unnecessary(const struct sk_buff *skb) |
2823 | { | |
5d0c2b95 | 2824 | return ((skb->ip_summed & CHECKSUM_UNNECESSARY) || skb->csum_valid); |
60476372 HX |
2825 | } |
2826 | ||
fb286bb2 HX |
2827 | /** |
2828 | * skb_checksum_complete - Calculate checksum of an entire packet | |
2829 | * @skb: packet to process | |
2830 | * | |
2831 | * This function calculates the checksum over the entire packet plus | |
2832 | * the value of skb->csum. The latter can be used to supply the | |
2833 | * checksum of a pseudo header as used by TCP/UDP. It returns the | |
2834 | * checksum. | |
2835 | * | |
2836 | * For protocols that contain complete checksums such as ICMP/TCP/UDP, | |
2837 | * this function can be used to verify that checksum on received | |
2838 | * packets. In that case the function should return zero if the | |
2839 | * checksum is correct. In particular, this function will return zero | |
2840 | * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the | |
2841 | * hardware has already verified the correctness of the checksum. | |
2842 | */ | |
4381ca3c | 2843 | static inline __sum16 skb_checksum_complete(struct sk_buff *skb) |
fb286bb2 | 2844 | { |
60476372 HX |
2845 | return skb_csum_unnecessary(skb) ? |
2846 | 0 : __skb_checksum_complete(skb); | |
fb286bb2 HX |
2847 | } |
2848 | ||
77cffe23 TH |
2849 | static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb) |
2850 | { | |
2851 | if (skb->ip_summed == CHECKSUM_UNNECESSARY) { | |
2852 | if (skb->csum_level == 0) | |
2853 | skb->ip_summed = CHECKSUM_NONE; | |
2854 | else | |
2855 | skb->csum_level--; | |
2856 | } | |
2857 | } | |
2858 | ||
2859 | static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb) | |
2860 | { | |
2861 | if (skb->ip_summed == CHECKSUM_UNNECESSARY) { | |
2862 | if (skb->csum_level < SKB_MAX_CSUM_LEVEL) | |
2863 | skb->csum_level++; | |
2864 | } else if (skb->ip_summed == CHECKSUM_NONE) { | |
2865 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
2866 | skb->csum_level = 0; | |
2867 | } | |
2868 | } | |
2869 | ||
5a212329 TH |
2870 | static inline void __skb_mark_checksum_bad(struct sk_buff *skb) |
2871 | { | |
2872 | /* Mark current checksum as bad (typically called from GRO | |
2873 | * path). In the case that ip_summed is CHECKSUM_NONE | |
2874 | * this must be the first checksum encountered in the packet. | |
2875 | * When ip_summed is CHECKSUM_UNNECESSARY, this is the first | |
2876 | * checksum after the last one validated. For UDP, a zero | |
2877 | * checksum can not be marked as bad. | |
2878 | */ | |
2879 | ||
2880 | if (skb->ip_summed == CHECKSUM_NONE || | |
2881 | skb->ip_summed == CHECKSUM_UNNECESSARY) | |
2882 | skb->csum_bad = 1; | |
2883 | } | |
2884 | ||
76ba0aae TH |
2885 | /* Check if we need to perform checksum complete validation. |
2886 | * | |
2887 | * Returns true if checksum complete is needed, false otherwise | |
2888 | * (either checksum is unnecessary or zero checksum is allowed). | |
2889 | */ | |
2890 | static inline bool __skb_checksum_validate_needed(struct sk_buff *skb, | |
2891 | bool zero_okay, | |
2892 | __sum16 check) | |
2893 | { | |
5d0c2b95 TH |
2894 | if (skb_csum_unnecessary(skb) || (zero_okay && !check)) { |
2895 | skb->csum_valid = 1; | |
77cffe23 | 2896 | __skb_decr_checksum_unnecessary(skb); |
76ba0aae TH |
2897 | return false; |
2898 | } | |
2899 | ||
2900 | return true; | |
2901 | } | |
2902 | ||
2903 | /* For small packets <= CHECKSUM_BREAK peform checksum complete directly | |
2904 | * in checksum_init. | |
2905 | */ | |
2906 | #define CHECKSUM_BREAK 76 | |
2907 | ||
2908 | /* Validate (init) checksum based on checksum complete. | |
2909 | * | |
2910 | * Return values: | |
2911 | * 0: checksum is validated or try to in skb_checksum_complete. In the latter | |
2912 | * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo | |
2913 | * checksum is stored in skb->csum for use in __skb_checksum_complete | |
2914 | * non-zero: value of invalid checksum | |
2915 | * | |
2916 | */ | |
2917 | static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb, | |
2918 | bool complete, | |
2919 | __wsum psum) | |
2920 | { | |
2921 | if (skb->ip_summed == CHECKSUM_COMPLETE) { | |
2922 | if (!csum_fold(csum_add(psum, skb->csum))) { | |
5d0c2b95 | 2923 | skb->csum_valid = 1; |
76ba0aae TH |
2924 | return 0; |
2925 | } | |
5a212329 TH |
2926 | } else if (skb->csum_bad) { |
2927 | /* ip_summed == CHECKSUM_NONE in this case */ | |
2928 | return 1; | |
76ba0aae TH |
2929 | } |
2930 | ||
2931 | skb->csum = psum; | |
2932 | ||
5d0c2b95 TH |
2933 | if (complete || skb->len <= CHECKSUM_BREAK) { |
2934 | __sum16 csum; | |
2935 | ||
2936 | csum = __skb_checksum_complete(skb); | |
2937 | skb->csum_valid = !csum; | |
2938 | return csum; | |
2939 | } | |
76ba0aae TH |
2940 | |
2941 | return 0; | |
2942 | } | |
2943 | ||
2944 | static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto) | |
2945 | { | |
2946 | return 0; | |
2947 | } | |
2948 | ||
2949 | /* Perform checksum validate (init). Note that this is a macro since we only | |
2950 | * want to calculate the pseudo header which is an input function if necessary. | |
2951 | * First we try to validate without any computation (checksum unnecessary) and | |
2952 | * then calculate based on checksum complete calling the function to compute | |
2953 | * pseudo header. | |
2954 | * | |
2955 | * Return values: | |
2956 | * 0: checksum is validated or try to in skb_checksum_complete | |
2957 | * non-zero: value of invalid checksum | |
2958 | */ | |
2959 | #define __skb_checksum_validate(skb, proto, complete, \ | |
2960 | zero_okay, check, compute_pseudo) \ | |
2961 | ({ \ | |
2962 | __sum16 __ret = 0; \ | |
5d0c2b95 | 2963 | skb->csum_valid = 0; \ |
76ba0aae TH |
2964 | if (__skb_checksum_validate_needed(skb, zero_okay, check)) \ |
2965 | __ret = __skb_checksum_validate_complete(skb, \ | |
2966 | complete, compute_pseudo(skb, proto)); \ | |
2967 | __ret; \ | |
2968 | }) | |
2969 | ||
2970 | #define skb_checksum_init(skb, proto, compute_pseudo) \ | |
2971 | __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo) | |
2972 | ||
2973 | #define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \ | |
2974 | __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo) | |
2975 | ||
2976 | #define skb_checksum_validate(skb, proto, compute_pseudo) \ | |
2977 | __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo) | |
2978 | ||
2979 | #define skb_checksum_validate_zero_check(skb, proto, check, \ | |
2980 | compute_pseudo) \ | |
2981 | __skb_checksum_validate_(skb, proto, true, true, check, compute_pseudo) | |
2982 | ||
2983 | #define skb_checksum_simple_validate(skb) \ | |
2984 | __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo) | |
2985 | ||
d96535a1 TH |
2986 | static inline bool __skb_checksum_convert_check(struct sk_buff *skb) |
2987 | { | |
2988 | return (skb->ip_summed == CHECKSUM_NONE && | |
2989 | skb->csum_valid && !skb->csum_bad); | |
2990 | } | |
2991 | ||
2992 | static inline void __skb_checksum_convert(struct sk_buff *skb, | |
2993 | __sum16 check, __wsum pseudo) | |
2994 | { | |
2995 | skb->csum = ~pseudo; | |
2996 | skb->ip_summed = CHECKSUM_COMPLETE; | |
2997 | } | |
2998 | ||
2999 | #define skb_checksum_try_convert(skb, proto, check, compute_pseudo) \ | |
3000 | do { \ | |
3001 | if (__skb_checksum_convert_check(skb)) \ | |
3002 | __skb_checksum_convert(skb, check, \ | |
3003 | compute_pseudo(skb, proto)); \ | |
3004 | } while (0) | |
3005 | ||
5f79e0f9 | 3006 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
7965bd4d | 3007 | void nf_conntrack_destroy(struct nf_conntrack *nfct); |
1da177e4 LT |
3008 | static inline void nf_conntrack_put(struct nf_conntrack *nfct) |
3009 | { | |
3010 | if (nfct && atomic_dec_and_test(&nfct->use)) | |
de6e05c4 | 3011 | nf_conntrack_destroy(nfct); |
1da177e4 LT |
3012 | } |
3013 | static inline void nf_conntrack_get(struct nf_conntrack *nfct) | |
3014 | { | |
3015 | if (nfct) | |
3016 | atomic_inc(&nfct->use); | |
3017 | } | |
2fc72c7b | 3018 | #endif |
1da177e4 LT |
3019 | #ifdef CONFIG_BRIDGE_NETFILTER |
3020 | static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) | |
3021 | { | |
3022 | if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) | |
3023 | kfree(nf_bridge); | |
3024 | } | |
3025 | static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) | |
3026 | { | |
3027 | if (nf_bridge) | |
3028 | atomic_inc(&nf_bridge->use); | |
3029 | } | |
3030 | #endif /* CONFIG_BRIDGE_NETFILTER */ | |
a193a4ab PM |
3031 | static inline void nf_reset(struct sk_buff *skb) |
3032 | { | |
5f79e0f9 | 3033 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
a193a4ab PM |
3034 | nf_conntrack_put(skb->nfct); |
3035 | skb->nfct = NULL; | |
2fc72c7b | 3036 | #endif |
a193a4ab PM |
3037 | #ifdef CONFIG_BRIDGE_NETFILTER |
3038 | nf_bridge_put(skb->nf_bridge); | |
3039 | skb->nf_bridge = NULL; | |
3040 | #endif | |
3041 | } | |
3042 | ||
124dff01 PM |
3043 | static inline void nf_reset_trace(struct sk_buff *skb) |
3044 | { | |
478b360a | 3045 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) |
130549fe G |
3046 | skb->nf_trace = 0; |
3047 | #endif | |
a193a4ab PM |
3048 | } |
3049 | ||
edda553c | 3050 | /* Note: This doesn't put any conntrack and bridge info in dst. */ |
b1937227 ED |
3051 | static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src, |
3052 | bool copy) | |
edda553c | 3053 | { |
5f79e0f9 | 3054 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
edda553c YK |
3055 | dst->nfct = src->nfct; |
3056 | nf_conntrack_get(src->nfct); | |
b1937227 ED |
3057 | if (copy) |
3058 | dst->nfctinfo = src->nfctinfo; | |
2fc72c7b | 3059 | #endif |
edda553c YK |
3060 | #ifdef CONFIG_BRIDGE_NETFILTER |
3061 | dst->nf_bridge = src->nf_bridge; | |
3062 | nf_bridge_get(src->nf_bridge); | |
3063 | #endif | |
478b360a | 3064 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) |
b1937227 ED |
3065 | if (copy) |
3066 | dst->nf_trace = src->nf_trace; | |
478b360a | 3067 | #endif |
edda553c YK |
3068 | } |
3069 | ||
e7ac05f3 YK |
3070 | static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) |
3071 | { | |
e7ac05f3 | 3072 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
5f79e0f9 | 3073 | nf_conntrack_put(dst->nfct); |
2fc72c7b | 3074 | #endif |
e7ac05f3 YK |
3075 | #ifdef CONFIG_BRIDGE_NETFILTER |
3076 | nf_bridge_put(dst->nf_bridge); | |
3077 | #endif | |
b1937227 | 3078 | __nf_copy(dst, src, true); |
e7ac05f3 YK |
3079 | } |
3080 | ||
984bc16c JM |
3081 | #ifdef CONFIG_NETWORK_SECMARK |
3082 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
3083 | { | |
3084 | to->secmark = from->secmark; | |
3085 | } | |
3086 | ||
3087 | static inline void skb_init_secmark(struct sk_buff *skb) | |
3088 | { | |
3089 | skb->secmark = 0; | |
3090 | } | |
3091 | #else | |
3092 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
3093 | { } | |
3094 | ||
3095 | static inline void skb_init_secmark(struct sk_buff *skb) | |
3096 | { } | |
3097 | #endif | |
3098 | ||
574f7194 EB |
3099 | static inline bool skb_irq_freeable(const struct sk_buff *skb) |
3100 | { | |
3101 | return !skb->destructor && | |
3102 | #if IS_ENABLED(CONFIG_XFRM) | |
3103 | !skb->sp && | |
3104 | #endif | |
3105 | #if IS_ENABLED(CONFIG_NF_CONNTRACK) | |
3106 | !skb->nfct && | |
3107 | #endif | |
3108 | !skb->_skb_refdst && | |
3109 | !skb_has_frag_list(skb); | |
3110 | } | |
3111 | ||
f25f4e44 PWJ |
3112 | static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping) |
3113 | { | |
f25f4e44 | 3114 | skb->queue_mapping = queue_mapping; |
f25f4e44 PWJ |
3115 | } |
3116 | ||
9247744e | 3117 | static inline u16 skb_get_queue_mapping(const struct sk_buff *skb) |
4e3ab47a | 3118 | { |
4e3ab47a | 3119 | return skb->queue_mapping; |
4e3ab47a PE |
3120 | } |
3121 | ||
f25f4e44 PWJ |
3122 | static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from) |
3123 | { | |
f25f4e44 | 3124 | to->queue_mapping = from->queue_mapping; |
f25f4e44 PWJ |
3125 | } |
3126 | ||
d5a9e24a DM |
3127 | static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue) |
3128 | { | |
3129 | skb->queue_mapping = rx_queue + 1; | |
3130 | } | |
3131 | ||
9247744e | 3132 | static inline u16 skb_get_rx_queue(const struct sk_buff *skb) |
d5a9e24a DM |
3133 | { |
3134 | return skb->queue_mapping - 1; | |
3135 | } | |
3136 | ||
9247744e | 3137 | static inline bool skb_rx_queue_recorded(const struct sk_buff *skb) |
d5a9e24a | 3138 | { |
a02cec21 | 3139 | return skb->queue_mapping != 0; |
d5a9e24a DM |
3140 | } |
3141 | ||
0e001614 | 3142 | u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb, |
7965bd4d | 3143 | unsigned int num_tx_queues); |
9247744e | 3144 | |
def8b4fa AD |
3145 | static inline struct sec_path *skb_sec_path(struct sk_buff *skb) |
3146 | { | |
0b3d8e08 | 3147 | #ifdef CONFIG_XFRM |
def8b4fa | 3148 | return skb->sp; |
def8b4fa | 3149 | #else |
def8b4fa | 3150 | return NULL; |
def8b4fa | 3151 | #endif |
0b3d8e08 | 3152 | } |
def8b4fa | 3153 | |
68c33163 PS |
3154 | /* Keeps track of mac header offset relative to skb->head. |
3155 | * It is useful for TSO of Tunneling protocol. e.g. GRE. | |
3156 | * For non-tunnel skb it points to skb_mac_header() and for | |
3347c960 ED |
3157 | * tunnel skb it points to outer mac header. |
3158 | * Keeps track of level of encapsulation of network headers. | |
3159 | */ | |
68c33163 | 3160 | struct skb_gso_cb { |
3347c960 ED |
3161 | int mac_offset; |
3162 | int encap_level; | |
7e2b10c1 | 3163 | __u16 csum_start; |
68c33163 PS |
3164 | }; |
3165 | #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb) | |
3166 | ||
3167 | static inline int skb_tnl_header_len(const struct sk_buff *inner_skb) | |
3168 | { | |
3169 | return (skb_mac_header(inner_skb) - inner_skb->head) - | |
3170 | SKB_GSO_CB(inner_skb)->mac_offset; | |
3171 | } | |
3172 | ||
1e2bd517 PS |
3173 | static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra) |
3174 | { | |
3175 | int new_headroom, headroom; | |
3176 | int ret; | |
3177 | ||
3178 | headroom = skb_headroom(skb); | |
3179 | ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC); | |
3180 | if (ret) | |
3181 | return ret; | |
3182 | ||
3183 | new_headroom = skb_headroom(skb); | |
3184 | SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom); | |
3185 | return 0; | |
3186 | } | |
3187 | ||
7e2b10c1 TH |
3188 | /* Compute the checksum for a gso segment. First compute the checksum value |
3189 | * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and | |
3190 | * then add in skb->csum (checksum from csum_start to end of packet). | |
3191 | * skb->csum and csum_start are then updated to reflect the checksum of the | |
3192 | * resultant packet starting from the transport header-- the resultant checksum | |
3193 | * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo | |
3194 | * header. | |
3195 | */ | |
3196 | static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res) | |
3197 | { | |
3198 | int plen = SKB_GSO_CB(skb)->csum_start - skb_headroom(skb) - | |
3199 | skb_transport_offset(skb); | |
3200 | __u16 csum; | |
3201 | ||
3202 | csum = csum_fold(csum_partial(skb_transport_header(skb), | |
3203 | plen, skb->csum)); | |
3204 | skb->csum = res; | |
3205 | SKB_GSO_CB(skb)->csum_start -= plen; | |
3206 | ||
3207 | return csum; | |
3208 | } | |
3209 | ||
bdcc0924 | 3210 | static inline bool skb_is_gso(const struct sk_buff *skb) |
89114afd HX |
3211 | { |
3212 | return skb_shinfo(skb)->gso_size; | |
3213 | } | |
3214 | ||
36a8f39e | 3215 | /* Note: Should be called only if skb_is_gso(skb) is true */ |
bdcc0924 | 3216 | static inline bool skb_is_gso_v6(const struct sk_buff *skb) |
eabd7e35 BG |
3217 | { |
3218 | return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6; | |
3219 | } | |
3220 | ||
7965bd4d | 3221 | void __skb_warn_lro_forwarding(const struct sk_buff *skb); |
4497b076 BH |
3222 | |
3223 | static inline bool skb_warn_if_lro(const struct sk_buff *skb) | |
3224 | { | |
3225 | /* LRO sets gso_size but not gso_type, whereas if GSO is really | |
3226 | * wanted then gso_type will be set. */ | |
05bdd2f1 ED |
3227 | const struct skb_shared_info *shinfo = skb_shinfo(skb); |
3228 | ||
b78462eb AD |
3229 | if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 && |
3230 | unlikely(shinfo->gso_type == 0)) { | |
4497b076 BH |
3231 | __skb_warn_lro_forwarding(skb); |
3232 | return true; | |
3233 | } | |
3234 | return false; | |
3235 | } | |
3236 | ||
35fc92a9 HX |
3237 | static inline void skb_forward_csum(struct sk_buff *skb) |
3238 | { | |
3239 | /* Unfortunately we don't support this one. Any brave souls? */ | |
3240 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
3241 | skb->ip_summed = CHECKSUM_NONE; | |
3242 | } | |
3243 | ||
bc8acf2c ED |
3244 | /** |
3245 | * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE | |
3246 | * @skb: skb to check | |
3247 | * | |
3248 | * fresh skbs have their ip_summed set to CHECKSUM_NONE. | |
3249 | * Instead of forcing ip_summed to CHECKSUM_NONE, we can | |
3250 | * use this helper, to document places where we make this assertion. | |
3251 | */ | |
05bdd2f1 | 3252 | static inline void skb_checksum_none_assert(const struct sk_buff *skb) |
bc8acf2c ED |
3253 | { |
3254 | #ifdef DEBUG | |
3255 | BUG_ON(skb->ip_summed != CHECKSUM_NONE); | |
3256 | #endif | |
3257 | } | |
3258 | ||
f35d9d8a | 3259 | bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); |
a6686f2f | 3260 | |
ed1f50c3 PD |
3261 | int skb_checksum_setup(struct sk_buff *skb, bool recalculate); |
3262 | ||
56193d1b AD |
3263 | u32 skb_get_poff(const struct sk_buff *skb); |
3264 | u32 __skb_get_poff(const struct sk_buff *skb, void *data, | |
3265 | const struct flow_keys *keys, int hlen); | |
f77668dc | 3266 | |
3a7c1ee4 AD |
3267 | /** |
3268 | * skb_head_is_locked - Determine if the skb->head is locked down | |
3269 | * @skb: skb to check | |
3270 | * | |
3271 | * The head on skbs build around a head frag can be removed if they are | |
3272 | * not cloned. This function returns true if the skb head is locked down | |
3273 | * due to either being allocated via kmalloc, or by being a clone with | |
3274 | * multiple references to the head. | |
3275 | */ | |
3276 | static inline bool skb_head_is_locked(const struct sk_buff *skb) | |
3277 | { | |
3278 | return !skb->head_frag || skb_cloned(skb); | |
3279 | } | |
fe6cc55f FW |
3280 | |
3281 | /** | |
3282 | * skb_gso_network_seglen - Return length of individual segments of a gso packet | |
3283 | * | |
3284 | * @skb: GSO skb | |
3285 | * | |
3286 | * skb_gso_network_seglen is used to determine the real size of the | |
3287 | * individual segments, including Layer3 (IP, IPv6) and L4 headers (TCP/UDP). | |
3288 | * | |
3289 | * The MAC/L2 header is not accounted for. | |
3290 | */ | |
3291 | static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb) | |
3292 | { | |
3293 | unsigned int hdr_len = skb_transport_header(skb) - | |
3294 | skb_network_header(skb); | |
3295 | return hdr_len + skb_gso_transport_seglen(skb); | |
3296 | } | |
1da177e4 LT |
3297 | #endif /* __KERNEL__ */ |
3298 | #endif /* _LINUX_SKBUFF_H */ |