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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 | 22 | #include <linux/cache.h> |
56b17425 | 23 | #include <linux/rbtree.h> |
51f3d02b | 24 | #include <linux/socket.h> |
1da177e4 | 25 | |
60063497 | 26 | #include <linux/atomic.h> |
1da177e4 LT |
27 | #include <asm/types.h> |
28 | #include <linux/spinlock.h> | |
1da177e4 | 29 | #include <linux/net.h> |
3fc7e8a6 | 30 | #include <linux/textsearch.h> |
1da177e4 | 31 | #include <net/checksum.h> |
a80958f4 | 32 | #include <linux/rcupdate.h> |
b7aa0bf7 | 33 | #include <linux/hrtimer.h> |
131ea667 | 34 | #include <linux/dma-mapping.h> |
c8f44aff | 35 | #include <linux/netdev_features.h> |
363ec392 | 36 | #include <linux/sched.h> |
5203cd28 | 37 | #include <net/flow_keys.h> |
1da177e4 | 38 | |
78ea85f1 DB |
39 | /* A. Checksumming of received packets by device. |
40 | * | |
41 | * CHECKSUM_NONE: | |
42 | * | |
43 | * Device failed to checksum this packet e.g. due to lack of capabilities. | |
44 | * The packet contains full (though not verified) checksum in packet but | |
45 | * not in skb->csum. Thus, skb->csum is undefined in this case. | |
46 | * | |
47 | * CHECKSUM_UNNECESSARY: | |
48 | * | |
49 | * The hardware you're dealing with doesn't calculate the full checksum | |
50 | * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums | |
77cffe23 TH |
51 | * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY |
52 | * if their checksums are okay. skb->csum is still undefined in this case | |
53 | * though. It is a bad option, but, unfortunately, nowadays most vendors do | |
54 | * this. Apparently with the secret goal to sell you new devices, when you | |
55 | * will add new protocol to your host, f.e. IPv6 8) | |
56 | * | |
57 | * CHECKSUM_UNNECESSARY is applicable to following protocols: | |
58 | * TCP: IPv6 and IPv4. | |
59 | * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a | |
60 | * zero UDP checksum for either IPv4 or IPv6, the networking stack | |
61 | * may perform further validation in this case. | |
62 | * GRE: only if the checksum is present in the header. | |
63 | * SCTP: indicates the CRC in SCTP header has been validated. | |
64 | * | |
65 | * skb->csum_level indicates the number of consecutive checksums found in | |
66 | * the packet minus one that have been verified as CHECKSUM_UNNECESSARY. | |
67 | * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet | |
68 | * and a device is able to verify the checksums for UDP (possibly zero), | |
69 | * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to | |
70 | * two. If the device were only able to verify the UDP checksum and not | |
71 | * GRE, either because it doesn't support GRE checksum of because GRE | |
72 | * checksum is bad, skb->csum_level would be set to zero (TCP checksum is | |
73 | * not considered in this case). | |
78ea85f1 DB |
74 | * |
75 | * CHECKSUM_COMPLETE: | |
76 | * | |
77 | * This is the most generic way. The device supplied checksum of the _whole_ | |
78 | * packet as seen by netif_rx() and fills out in skb->csum. Meaning, the | |
79 | * hardware doesn't need to parse L3/L4 headers to implement this. | |
80 | * | |
81 | * Note: Even if device supports only some protocols, but is able to produce | |
82 | * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY. | |
83 | * | |
84 | * CHECKSUM_PARTIAL: | |
85 | * | |
86 | * This is identical to the case for output below. This may occur on a packet | |
87 | * received directly from another Linux OS, e.g., a virtualized Linux kernel | |
88 | * on the same host. The packet can be treated in the same way as | |
89 | * CHECKSUM_UNNECESSARY, except that on output (i.e., forwarding) the | |
90 | * checksum must be filled in by the OS or the hardware. | |
91 | * | |
92 | * B. Checksumming on output. | |
93 | * | |
94 | * CHECKSUM_NONE: | |
95 | * | |
96 | * The skb was already checksummed by the protocol, or a checksum is not | |
97 | * required. | |
98 | * | |
99 | * CHECKSUM_PARTIAL: | |
100 | * | |
101 | * The device is required to checksum the packet as seen by hard_start_xmit() | |
102 | * from skb->csum_start up to the end, and to record/write the checksum at | |
103 | * offset skb->csum_start + skb->csum_offset. | |
104 | * | |
105 | * The device must show its capabilities in dev->features, set up at device | |
106 | * setup time, e.g. netdev_features.h: | |
107 | * | |
108 | * NETIF_F_HW_CSUM - It's a clever device, it's able to checksum everything. | |
109 | * NETIF_F_IP_CSUM - Device is dumb, it's able to checksum only TCP/UDP over | |
110 | * IPv4. Sigh. Vendors like this way for an unknown reason. | |
111 | * Though, see comment above about CHECKSUM_UNNECESSARY. 8) | |
112 | * NETIF_F_IPV6_CSUM - About as dumb as the last one but does IPv6 instead. | |
113 | * NETIF_F_... - Well, you get the picture. | |
114 | * | |
115 | * CHECKSUM_UNNECESSARY: | |
116 | * | |
117 | * Normally, the device will do per protocol specific checksumming. Protocol | |
118 | * implementations that do not want the NIC to perform the checksum | |
119 | * calculation should use this flag in their outgoing skbs. | |
120 | * | |
121 | * NETIF_F_FCOE_CRC - This indicates that the device can do FCoE FC CRC | |
122 | * offload. Correspondingly, the FCoE protocol driver | |
123 | * stack should use CHECKSUM_UNNECESSARY. | |
124 | * | |
125 | * Any questions? No questions, good. --ANK | |
126 | */ | |
127 | ||
60476372 | 128 | /* Don't change this without changing skb_csum_unnecessary! */ |
78ea85f1 DB |
129 | #define CHECKSUM_NONE 0 |
130 | #define CHECKSUM_UNNECESSARY 1 | |
131 | #define CHECKSUM_COMPLETE 2 | |
132 | #define CHECKSUM_PARTIAL 3 | |
1da177e4 | 133 | |
77cffe23 TH |
134 | /* Maximum value in skb->csum_level */ |
135 | #define SKB_MAX_CSUM_LEVEL 3 | |
136 | ||
0bec8c88 | 137 | #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES) |
fc910a27 | 138 | #define SKB_WITH_OVERHEAD(X) \ |
deea84b0 | 139 | ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) |
fc910a27 DM |
140 | #define SKB_MAX_ORDER(X, ORDER) \ |
141 | SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) | |
1da177e4 LT |
142 | #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) |
143 | #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) | |
144 | ||
87fb4b7b ED |
145 | /* return minimum truesize of one skb containing X bytes of data */ |
146 | #define SKB_TRUESIZE(X) ((X) + \ | |
147 | SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \ | |
148 | SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) | |
149 | ||
1da177e4 | 150 | struct net_device; |
716ea3a7 | 151 | struct scatterlist; |
9c55e01c | 152 | struct pipe_inode_info; |
a8f820aa | 153 | struct iov_iter; |
1da177e4 | 154 | |
5f79e0f9 | 155 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
1da177e4 LT |
156 | struct nf_conntrack { |
157 | atomic_t use; | |
1da177e4 | 158 | }; |
5f79e0f9 | 159 | #endif |
1da177e4 | 160 | |
34666d46 | 161 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
1da177e4 | 162 | struct nf_bridge_info { |
bf1ac5ca ED |
163 | atomic_t use; |
164 | unsigned int mask; | |
165 | struct net_device *physindev; | |
166 | struct net_device *physoutdev; | |
167 | unsigned long data[32 / sizeof(unsigned long)]; | |
1da177e4 LT |
168 | }; |
169 | #endif | |
170 | ||
1da177e4 LT |
171 | struct sk_buff_head { |
172 | /* These two members must be first. */ | |
173 | struct sk_buff *next; | |
174 | struct sk_buff *prev; | |
175 | ||
176 | __u32 qlen; | |
177 | spinlock_t lock; | |
178 | }; | |
179 | ||
180 | struct sk_buff; | |
181 | ||
9d4dde52 IC |
182 | /* To allow 64K frame to be packed as single skb without frag_list we |
183 | * require 64K/PAGE_SIZE pages plus 1 additional page to allow for | |
184 | * buffers which do not start on a page boundary. | |
185 | * | |
186 | * Since GRO uses frags we allocate at least 16 regardless of page | |
187 | * size. | |
a715dea3 | 188 | */ |
9d4dde52 | 189 | #if (65536/PAGE_SIZE + 1) < 16 |
eec00954 | 190 | #define MAX_SKB_FRAGS 16UL |
a715dea3 | 191 | #else |
9d4dde52 | 192 | #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1) |
a715dea3 | 193 | #endif |
1da177e4 LT |
194 | |
195 | typedef struct skb_frag_struct skb_frag_t; | |
196 | ||
197 | struct skb_frag_struct { | |
a8605c60 IC |
198 | struct { |
199 | struct page *p; | |
200 | } page; | |
cb4dfe56 | 201 | #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536) |
a309bb07 DM |
202 | __u32 page_offset; |
203 | __u32 size; | |
cb4dfe56 ED |
204 | #else |
205 | __u16 page_offset; | |
206 | __u16 size; | |
207 | #endif | |
1da177e4 LT |
208 | }; |
209 | ||
9e903e08 ED |
210 | static inline unsigned int skb_frag_size(const skb_frag_t *frag) |
211 | { | |
212 | return frag->size; | |
213 | } | |
214 | ||
215 | static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) | |
216 | { | |
217 | frag->size = size; | |
218 | } | |
219 | ||
220 | static inline void skb_frag_size_add(skb_frag_t *frag, int delta) | |
221 | { | |
222 | frag->size += delta; | |
223 | } | |
224 | ||
225 | static inline void skb_frag_size_sub(skb_frag_t *frag, int delta) | |
226 | { | |
227 | frag->size -= delta; | |
228 | } | |
229 | ||
ac45f602 PO |
230 | #define HAVE_HW_TIME_STAMP |
231 | ||
232 | /** | |
d3a21be8 | 233 | * struct skb_shared_hwtstamps - hardware time stamps |
ac45f602 PO |
234 | * @hwtstamp: hardware time stamp transformed into duration |
235 | * since arbitrary point in time | |
ac45f602 PO |
236 | * |
237 | * Software time stamps generated by ktime_get_real() are stored in | |
4d276eb6 | 238 | * skb->tstamp. |
ac45f602 PO |
239 | * |
240 | * hwtstamps can only be compared against other hwtstamps from | |
241 | * the same device. | |
242 | * | |
243 | * This structure is attached to packets as part of the | |
244 | * &skb_shared_info. Use skb_hwtstamps() to get a pointer. | |
245 | */ | |
246 | struct skb_shared_hwtstamps { | |
247 | ktime_t hwtstamp; | |
ac45f602 PO |
248 | }; |
249 | ||
2244d07b OH |
250 | /* Definitions for tx_flags in struct skb_shared_info */ |
251 | enum { | |
252 | /* generate hardware time stamp */ | |
253 | SKBTX_HW_TSTAMP = 1 << 0, | |
254 | ||
e7fd2885 | 255 | /* generate software time stamp when queueing packet to NIC */ |
2244d07b OH |
256 | SKBTX_SW_TSTAMP = 1 << 1, |
257 | ||
258 | /* device driver is going to provide hardware time stamp */ | |
259 | SKBTX_IN_PROGRESS = 1 << 2, | |
260 | ||
a6686f2f | 261 | /* device driver supports TX zero-copy buffers */ |
62b1a8ab | 262 | SKBTX_DEV_ZEROCOPY = 1 << 3, |
6e3e939f JB |
263 | |
264 | /* generate wifi status information (where possible) */ | |
62b1a8ab | 265 | SKBTX_WIFI_STATUS = 1 << 4, |
c9af6db4 PS |
266 | |
267 | /* This indicates at least one fragment might be overwritten | |
268 | * (as in vmsplice(), sendfile() ...) | |
269 | * If we need to compute a TX checksum, we'll need to copy | |
270 | * all frags to avoid possible bad checksum | |
271 | */ | |
272 | SKBTX_SHARED_FRAG = 1 << 5, | |
e7fd2885 WB |
273 | |
274 | /* generate software time stamp when entering packet scheduling */ | |
275 | SKBTX_SCHED_TSTAMP = 1 << 6, | |
e1c8a607 WB |
276 | |
277 | /* generate software timestamp on peer data acknowledgment */ | |
278 | SKBTX_ACK_TSTAMP = 1 << 7, | |
a6686f2f SM |
279 | }; |
280 | ||
e1c8a607 WB |
281 | #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \ |
282 | SKBTX_SCHED_TSTAMP | \ | |
283 | SKBTX_ACK_TSTAMP) | |
f24b9be5 WB |
284 | #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP) |
285 | ||
a6686f2f SM |
286 | /* |
287 | * The callback notifies userspace to release buffers when skb DMA is done in | |
288 | * lower device, the skb last reference should be 0 when calling this. | |
e19d6763 MT |
289 | * The zerocopy_success argument is true if zero copy transmit occurred, |
290 | * false on data copy or out of memory error caused by data copy attempt. | |
ca8f4fb2 MT |
291 | * The ctx field is used to track device context. |
292 | * The desc field is used to track userspace buffer index. | |
a6686f2f SM |
293 | */ |
294 | struct ubuf_info { | |
e19d6763 | 295 | void (*callback)(struct ubuf_info *, bool zerocopy_success); |
ca8f4fb2 | 296 | void *ctx; |
a6686f2f | 297 | unsigned long desc; |
ac45f602 PO |
298 | }; |
299 | ||
1da177e4 LT |
300 | /* This data is invariant across clones and lives at |
301 | * the end of the header data, ie. at skb->end. | |
302 | */ | |
303 | struct skb_shared_info { | |
9f42f126 IC |
304 | unsigned char nr_frags; |
305 | __u8 tx_flags; | |
7967168c HX |
306 | unsigned short gso_size; |
307 | /* Warning: this field is not always filled in (UFO)! */ | |
308 | unsigned short gso_segs; | |
309 | unsigned short gso_type; | |
1da177e4 | 310 | struct sk_buff *frag_list; |
ac45f602 | 311 | struct skb_shared_hwtstamps hwtstamps; |
09c2d251 | 312 | u32 tskey; |
9f42f126 | 313 | __be32 ip6_frag_id; |
ec7d2f2c ED |
314 | |
315 | /* | |
316 | * Warning : all fields before dataref are cleared in __alloc_skb() | |
317 | */ | |
318 | atomic_t dataref; | |
319 | ||
69e3c75f JB |
320 | /* Intermediate layers must ensure that destructor_arg |
321 | * remains valid until skb destructor */ | |
322 | void * destructor_arg; | |
a6686f2f | 323 | |
fed66381 ED |
324 | /* must be last field, see pskb_expand_head() */ |
325 | skb_frag_t frags[MAX_SKB_FRAGS]; | |
1da177e4 LT |
326 | }; |
327 | ||
328 | /* We divide dataref into two halves. The higher 16 bits hold references | |
329 | * to the payload part of skb->data. The lower 16 bits hold references to | |
334a8132 PM |
330 | * the entire skb->data. A clone of a headerless skb holds the length of |
331 | * the header in skb->hdr_len. | |
1da177e4 LT |
332 | * |
333 | * All users must obey the rule that the skb->data reference count must be | |
334 | * greater than or equal to the payload reference count. | |
335 | * | |
336 | * Holding a reference to the payload part means that the user does not | |
337 | * care about modifications to the header part of skb->data. | |
338 | */ | |
339 | #define SKB_DATAREF_SHIFT 16 | |
340 | #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) | |
341 | ||
d179cd12 DM |
342 | |
343 | enum { | |
c8753d55 VS |
344 | SKB_FCLONE_UNAVAILABLE, /* skb has no fclone (from head_cache) */ |
345 | SKB_FCLONE_ORIG, /* orig skb (from fclone_cache) */ | |
346 | SKB_FCLONE_CLONE, /* companion fclone skb (from fclone_cache) */ | |
347 | SKB_FCLONE_FREE, /* this companion fclone skb is available */ | |
d179cd12 DM |
348 | }; |
349 | ||
7967168c HX |
350 | enum { |
351 | SKB_GSO_TCPV4 = 1 << 0, | |
f83ef8c0 | 352 | SKB_GSO_UDP = 1 << 1, |
576a30eb HX |
353 | |
354 | /* This indicates the skb is from an untrusted source. */ | |
355 | SKB_GSO_DODGY = 1 << 2, | |
b0da8537 MC |
356 | |
357 | /* This indicates the tcp segment has CWR set. */ | |
f83ef8c0 HX |
358 | SKB_GSO_TCP_ECN = 1 << 3, |
359 | ||
360 | SKB_GSO_TCPV6 = 1 << 4, | |
01d5b2fc CL |
361 | |
362 | SKB_GSO_FCOE = 1 << 5, | |
68c33163 PS |
363 | |
364 | SKB_GSO_GRE = 1 << 6, | |
73136267 | 365 | |
4b28252c | 366 | SKB_GSO_GRE_CSUM = 1 << 7, |
0d89d203 | 367 | |
4b28252c | 368 | SKB_GSO_IPIP = 1 << 8, |
cb32f511 | 369 | |
4b28252c | 370 | SKB_GSO_SIT = 1 << 9, |
61c1db7f | 371 | |
4b28252c | 372 | SKB_GSO_UDP_TUNNEL = 1 << 10, |
0f4f4ffa TH |
373 | |
374 | SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11, | |
4749c09c | 375 | |
59b93b41 | 376 | SKB_GSO_TUNNEL_REMCSUM = 1 << 12, |
7967168c HX |
377 | }; |
378 | ||
2e07fa9c ACM |
379 | #if BITS_PER_LONG > 32 |
380 | #define NET_SKBUFF_DATA_USES_OFFSET 1 | |
381 | #endif | |
382 | ||
383 | #ifdef NET_SKBUFF_DATA_USES_OFFSET | |
384 | typedef unsigned int sk_buff_data_t; | |
385 | #else | |
386 | typedef unsigned char *sk_buff_data_t; | |
387 | #endif | |
388 | ||
363ec392 ED |
389 | /** |
390 | * struct skb_mstamp - multi resolution time stamps | |
391 | * @stamp_us: timestamp in us resolution | |
392 | * @stamp_jiffies: timestamp in jiffies | |
393 | */ | |
394 | struct skb_mstamp { | |
395 | union { | |
396 | u64 v64; | |
397 | struct { | |
398 | u32 stamp_us; | |
399 | u32 stamp_jiffies; | |
400 | }; | |
401 | }; | |
402 | }; | |
403 | ||
404 | /** | |
405 | * skb_mstamp_get - get current timestamp | |
406 | * @cl: place to store timestamps | |
407 | */ | |
408 | static inline void skb_mstamp_get(struct skb_mstamp *cl) | |
409 | { | |
410 | u64 val = local_clock(); | |
411 | ||
412 | do_div(val, NSEC_PER_USEC); | |
413 | cl->stamp_us = (u32)val; | |
414 | cl->stamp_jiffies = (u32)jiffies; | |
415 | } | |
416 | ||
417 | /** | |
418 | * skb_mstamp_delta - compute the difference in usec between two skb_mstamp | |
419 | * @t1: pointer to newest sample | |
420 | * @t0: pointer to oldest sample | |
421 | */ | |
422 | static inline u32 skb_mstamp_us_delta(const struct skb_mstamp *t1, | |
423 | const struct skb_mstamp *t0) | |
424 | { | |
425 | s32 delta_us = t1->stamp_us - t0->stamp_us; | |
426 | u32 delta_jiffies = t1->stamp_jiffies - t0->stamp_jiffies; | |
427 | ||
428 | /* If delta_us is negative, this might be because interval is too big, | |
429 | * or local_clock() drift is too big : fallback using jiffies. | |
430 | */ | |
431 | if (delta_us <= 0 || | |
432 | delta_jiffies >= (INT_MAX / (USEC_PER_SEC / HZ))) | |
433 | ||
434 | delta_us = jiffies_to_usecs(delta_jiffies); | |
435 | ||
436 | return delta_us; | |
437 | } | |
438 | ||
439 | ||
1da177e4 LT |
440 | /** |
441 | * struct sk_buff - socket buffer | |
442 | * @next: Next buffer in list | |
443 | * @prev: Previous buffer in list | |
363ec392 | 444 | * @tstamp: Time we arrived/left |
56b17425 | 445 | * @rbnode: RB tree node, alternative to next/prev for netem/tcp |
d84e0bd7 | 446 | * @sk: Socket we are owned by |
1da177e4 | 447 | * @dev: Device we arrived on/are leaving by |
d84e0bd7 | 448 | * @cb: Control buffer. Free for use by every layer. Put private vars here |
7fee226a | 449 | * @_skb_refdst: destination entry (with norefcount bit) |
67be2dd1 | 450 | * @sp: the security path, used for xfrm |
1da177e4 LT |
451 | * @len: Length of actual data |
452 | * @data_len: Data length | |
453 | * @mac_len: Length of link layer header | |
334a8132 | 454 | * @hdr_len: writable header length of cloned skb |
663ead3b HX |
455 | * @csum: Checksum (must include start/offset pair) |
456 | * @csum_start: Offset from skb->head where checksumming should start | |
457 | * @csum_offset: Offset from csum_start where checksum should be stored | |
d84e0bd7 | 458 | * @priority: Packet queueing priority |
60ff7467 | 459 | * @ignore_df: allow local fragmentation |
1da177e4 | 460 | * @cloned: Head may be cloned (check refcnt to be sure) |
d84e0bd7 | 461 | * @ip_summed: Driver fed us an IP checksum |
1da177e4 | 462 | * @nohdr: Payload reference only, must not modify header |
d84e0bd7 | 463 | * @nfctinfo: Relationship of this skb to the connection |
1da177e4 | 464 | * @pkt_type: Packet class |
c83c2486 | 465 | * @fclone: skbuff clone status |
c83c2486 | 466 | * @ipvs_property: skbuff is owned by ipvs |
31729363 RD |
467 | * @peeked: this packet has been seen already, so stats have been |
468 | * done for it, don't do them again | |
ba9dda3a | 469 | * @nf_trace: netfilter packet trace flag |
d84e0bd7 DB |
470 | * @protocol: Packet protocol from driver |
471 | * @destructor: Destruct function | |
472 | * @nfct: Associated connection, if any | |
1da177e4 | 473 | * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c |
8964be4a | 474 | * @skb_iif: ifindex of device we arrived on |
1da177e4 LT |
475 | * @tc_index: Traffic control index |
476 | * @tc_verd: traffic control verdict | |
61b905da | 477 | * @hash: the packet hash |
d84e0bd7 | 478 | * @queue_mapping: Queue mapping for multiqueue devices |
0b725a2c | 479 | * @xmit_more: More SKBs are pending for this queue |
553a5672 | 480 | * @ndisc_nodetype: router type (from link layer) |
d84e0bd7 | 481 | * @ooo_okay: allow the mapping of a socket to a queue to be changed |
61b905da | 482 | * @l4_hash: indicate hash is a canonical 4-tuple hash over transport |
4ca2462e | 483 | * ports. |
a3b18ddb | 484 | * @sw_hash: indicates hash was computed in software stack |
6e3e939f JB |
485 | * @wifi_acked_valid: wifi_acked was set |
486 | * @wifi_acked: whether frame was acked on wifi or not | |
3bdc0eba | 487 | * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS |
06021292 | 488 | * @napi_id: id of the NAPI struct this skb came from |
984bc16c | 489 | * @secmark: security marking |
d84e0bd7 DB |
490 | * @mark: Generic packet mark |
491 | * @dropcount: total number of sk_receive_queue overflows | |
86a9bad3 | 492 | * @vlan_proto: vlan encapsulation protocol |
6aa895b0 | 493 | * @vlan_tci: vlan tag control information |
0d89d203 | 494 | * @inner_protocol: Protocol (encapsulation) |
6a674e9c JG |
495 | * @inner_transport_header: Inner transport layer header (encapsulation) |
496 | * @inner_network_header: Network layer header (encapsulation) | |
aefbd2b3 | 497 | * @inner_mac_header: Link layer header (encapsulation) |
d84e0bd7 DB |
498 | * @transport_header: Transport layer header |
499 | * @network_header: Network layer header | |
500 | * @mac_header: Link layer header | |
501 | * @tail: Tail pointer | |
502 | * @end: End pointer | |
503 | * @head: Head of buffer | |
504 | * @data: Data head pointer | |
505 | * @truesize: Buffer size | |
506 | * @users: User count - see {datagram,tcp}.c | |
1da177e4 LT |
507 | */ |
508 | ||
509 | struct sk_buff { | |
363ec392 | 510 | union { |
56b17425 ED |
511 | struct { |
512 | /* These two members must be first. */ | |
513 | struct sk_buff *next; | |
514 | struct sk_buff *prev; | |
515 | ||
516 | union { | |
517 | ktime_t tstamp; | |
518 | struct skb_mstamp skb_mstamp; | |
519 | }; | |
520 | }; | |
521 | struct rb_node rbnode; /* used in netem & tcp stack */ | |
363ec392 | 522 | }; |
da3f5cf1 | 523 | struct sock *sk; |
1da177e4 | 524 | struct net_device *dev; |
1da177e4 | 525 | |
1da177e4 LT |
526 | /* |
527 | * This is the control buffer. It is free to use for every | |
528 | * layer. Please put your private variables there. If you | |
529 | * want to keep them across layers you have to do a skb_clone() | |
530 | * first. This is owned by whoever has the skb queued ATM. | |
531 | */ | |
da3f5cf1 | 532 | char cb[48] __aligned(8); |
1da177e4 | 533 | |
7fee226a | 534 | unsigned long _skb_refdst; |
b1937227 | 535 | void (*destructor)(struct sk_buff *skb); |
da3f5cf1 FF |
536 | #ifdef CONFIG_XFRM |
537 | struct sec_path *sp; | |
b1937227 ED |
538 | #endif |
539 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) | |
540 | struct nf_conntrack *nfct; | |
541 | #endif | |
85224844 | 542 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
b1937227 | 543 | struct nf_bridge_info *nf_bridge; |
da3f5cf1 | 544 | #endif |
1da177e4 | 545 | unsigned int len, |
334a8132 PM |
546 | data_len; |
547 | __u16 mac_len, | |
548 | hdr_len; | |
b1937227 ED |
549 | |
550 | /* Following fields are _not_ copied in __copy_skb_header() | |
551 | * Note that queue_mapping is here mostly to fill a hole. | |
552 | */ | |
fe55f6d5 | 553 | kmemcheck_bitfield_begin(flags1); |
b1937227 ED |
554 | __u16 queue_mapping; |
555 | __u8 cloned:1, | |
6869c4d8 | 556 | nohdr:1, |
b84f4cc9 | 557 | fclone:2, |
a59322be | 558 | peeked:1, |
b1937227 ED |
559 | head_frag:1, |
560 | xmit_more:1; | |
561 | /* one bit hole */ | |
fe55f6d5 | 562 | kmemcheck_bitfield_end(flags1); |
4031ae6e | 563 | |
b1937227 ED |
564 | /* fields enclosed in headers_start/headers_end are copied |
565 | * using a single memcpy() in __copy_skb_header() | |
566 | */ | |
ebcf34f3 | 567 | /* private: */ |
b1937227 | 568 | __u32 headers_start[0]; |
ebcf34f3 | 569 | /* public: */ |
4031ae6e | 570 | |
233577a2 HFS |
571 | /* if you move pkt_type around you also must adapt those constants */ |
572 | #ifdef __BIG_ENDIAN_BITFIELD | |
573 | #define PKT_TYPE_MAX (7 << 5) | |
574 | #else | |
575 | #define PKT_TYPE_MAX 7 | |
1da177e4 | 576 | #endif |
233577a2 | 577 | #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) |
fe55f6d5 | 578 | |
233577a2 | 579 | __u8 __pkt_type_offset[0]; |
b1937227 | 580 | __u8 pkt_type:3; |
c93bdd0e | 581 | __u8 pfmemalloc:1; |
b1937227 ED |
582 | __u8 ignore_df:1; |
583 | __u8 nfctinfo:3; | |
584 | ||
585 | __u8 nf_trace:1; | |
586 | __u8 ip_summed:2; | |
3853b584 | 587 | __u8 ooo_okay:1; |
61b905da | 588 | __u8 l4_hash:1; |
a3b18ddb | 589 | __u8 sw_hash:1; |
6e3e939f JB |
590 | __u8 wifi_acked_valid:1; |
591 | __u8 wifi_acked:1; | |
b1937227 | 592 | |
3bdc0eba | 593 | __u8 no_fcs:1; |
77cffe23 | 594 | /* Indicates the inner headers are valid in the skbuff. */ |
6a674e9c | 595 | __u8 encapsulation:1; |
7e2b10c1 | 596 | __u8 encap_hdr_csum:1; |
5d0c2b95 | 597 | __u8 csum_valid:1; |
7e3cead5 | 598 | __u8 csum_complete_sw:1; |
b1937227 ED |
599 | __u8 csum_level:2; |
600 | __u8 csum_bad:1; | |
fe55f6d5 | 601 | |
b1937227 ED |
602 | #ifdef CONFIG_IPV6_NDISC_NODETYPE |
603 | __u8 ndisc_nodetype:2; | |
604 | #endif | |
605 | __u8 ipvs_property:1; | |
8bce6d7d | 606 | __u8 inner_protocol_type:1; |
e585f236 TH |
607 | __u8 remcsum_offload:1; |
608 | /* 3 or 5 bit hole */ | |
b1937227 ED |
609 | |
610 | #ifdef CONFIG_NET_SCHED | |
611 | __u16 tc_index; /* traffic control index */ | |
612 | #ifdef CONFIG_NET_CLS_ACT | |
613 | __u16 tc_verd; /* traffic control verdict */ | |
614 | #endif | |
615 | #endif | |
fe55f6d5 | 616 | |
b1937227 ED |
617 | union { |
618 | __wsum csum; | |
619 | struct { | |
620 | __u16 csum_start; | |
621 | __u16 csum_offset; | |
622 | }; | |
623 | }; | |
624 | __u32 priority; | |
625 | int skb_iif; | |
626 | __u32 hash; | |
627 | __be16 vlan_proto; | |
628 | __u16 vlan_tci; | |
7bced397 DW |
629 | #ifdef CONFIG_NET_RX_BUSY_POLL |
630 | unsigned int napi_id; | |
97fc2f08 | 631 | #endif |
984bc16c JM |
632 | #ifdef CONFIG_NETWORK_SECMARK |
633 | __u32 secmark; | |
634 | #endif | |
3b885787 NH |
635 | union { |
636 | __u32 mark; | |
637 | __u32 dropcount; | |
16fad69c | 638 | __u32 reserved_tailroom; |
3b885787 | 639 | }; |
1da177e4 | 640 | |
8bce6d7d TH |
641 | union { |
642 | __be16 inner_protocol; | |
643 | __u8 inner_ipproto; | |
644 | }; | |
645 | ||
1a37e412 SH |
646 | __u16 inner_transport_header; |
647 | __u16 inner_network_header; | |
648 | __u16 inner_mac_header; | |
b1937227 ED |
649 | |
650 | __be16 protocol; | |
1a37e412 SH |
651 | __u16 transport_header; |
652 | __u16 network_header; | |
653 | __u16 mac_header; | |
b1937227 | 654 | |
ebcf34f3 | 655 | /* private: */ |
b1937227 | 656 | __u32 headers_end[0]; |
ebcf34f3 | 657 | /* public: */ |
b1937227 | 658 | |
1da177e4 | 659 | /* These elements must be at the end, see alloc_skb() for details. */ |
27a884dc | 660 | sk_buff_data_t tail; |
4305b541 | 661 | sk_buff_data_t end; |
1da177e4 | 662 | unsigned char *head, |
4305b541 | 663 | *data; |
27a884dc ACM |
664 | unsigned int truesize; |
665 | atomic_t users; | |
1da177e4 LT |
666 | }; |
667 | ||
668 | #ifdef __KERNEL__ | |
669 | /* | |
670 | * Handling routines are only of interest to the kernel | |
671 | */ | |
672 | #include <linux/slab.h> | |
673 | ||
1da177e4 | 674 | |
c93bdd0e MG |
675 | #define SKB_ALLOC_FCLONE 0x01 |
676 | #define SKB_ALLOC_RX 0x02 | |
677 | ||
678 | /* Returns true if the skb was allocated from PFMEMALLOC reserves */ | |
679 | static inline bool skb_pfmemalloc(const struct sk_buff *skb) | |
680 | { | |
681 | return unlikely(skb->pfmemalloc); | |
682 | } | |
683 | ||
7fee226a ED |
684 | /* |
685 | * skb might have a dst pointer attached, refcounted or not. | |
686 | * _skb_refdst low order bit is set if refcount was _not_ taken | |
687 | */ | |
688 | #define SKB_DST_NOREF 1UL | |
689 | #define SKB_DST_PTRMASK ~(SKB_DST_NOREF) | |
690 | ||
691 | /** | |
692 | * skb_dst - returns skb dst_entry | |
693 | * @skb: buffer | |
694 | * | |
695 | * Returns skb dst_entry, regardless of reference taken or not. | |
696 | */ | |
adf30907 ED |
697 | static inline struct dst_entry *skb_dst(const struct sk_buff *skb) |
698 | { | |
7fee226a ED |
699 | /* If refdst was not refcounted, check we still are in a |
700 | * rcu_read_lock section | |
701 | */ | |
702 | WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) && | |
703 | !rcu_read_lock_held() && | |
704 | !rcu_read_lock_bh_held()); | |
705 | return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK); | |
adf30907 ED |
706 | } |
707 | ||
7fee226a ED |
708 | /** |
709 | * skb_dst_set - sets skb dst | |
710 | * @skb: buffer | |
711 | * @dst: dst entry | |
712 | * | |
713 | * Sets skb dst, assuming a reference was taken on dst and should | |
714 | * be released by skb_dst_drop() | |
715 | */ | |
adf30907 ED |
716 | static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) |
717 | { | |
7fee226a ED |
718 | skb->_skb_refdst = (unsigned long)dst; |
719 | } | |
720 | ||
7965bd4d JP |
721 | void __skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst, |
722 | bool force); | |
932bc4d7 JA |
723 | |
724 | /** | |
725 | * skb_dst_set_noref - sets skb dst, hopefully, without taking reference | |
726 | * @skb: buffer | |
727 | * @dst: dst entry | |
728 | * | |
729 | * Sets skb dst, assuming a reference was not taken on dst. | |
730 | * If dst entry is cached, we do not take reference and dst_release | |
731 | * will be avoided by refdst_drop. If dst entry is not cached, we take | |
732 | * reference, so that last dst_release can destroy the dst immediately. | |
733 | */ | |
734 | static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst) | |
735 | { | |
736 | __skb_dst_set_noref(skb, dst, false); | |
737 | } | |
738 | ||
739 | /** | |
740 | * skb_dst_set_noref_force - sets skb dst, without taking reference | |
741 | * @skb: buffer | |
742 | * @dst: dst entry | |
743 | * | |
744 | * Sets skb dst, assuming a reference was not taken on dst. | |
745 | * No reference is taken and no dst_release will be called. While for | |
746 | * cached dsts deferred reclaim is a basic feature, for entries that are | |
747 | * not cached it is caller's job to guarantee that last dst_release for | |
748 | * provided dst happens when nobody uses it, eg. after a RCU grace period. | |
749 | */ | |
750 | static inline void skb_dst_set_noref_force(struct sk_buff *skb, | |
751 | struct dst_entry *dst) | |
752 | { | |
753 | __skb_dst_set_noref(skb, dst, true); | |
754 | } | |
7fee226a ED |
755 | |
756 | /** | |
25985edc | 757 | * skb_dst_is_noref - Test if skb dst isn't refcounted |
7fee226a ED |
758 | * @skb: buffer |
759 | */ | |
760 | static inline bool skb_dst_is_noref(const struct sk_buff *skb) | |
761 | { | |
762 | return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb); | |
adf30907 ED |
763 | } |
764 | ||
511c3f92 ED |
765 | static inline struct rtable *skb_rtable(const struct sk_buff *skb) |
766 | { | |
adf30907 | 767 | return (struct rtable *)skb_dst(skb); |
511c3f92 ED |
768 | } |
769 | ||
7965bd4d JP |
770 | void kfree_skb(struct sk_buff *skb); |
771 | void kfree_skb_list(struct sk_buff *segs); | |
772 | void skb_tx_error(struct sk_buff *skb); | |
773 | void consume_skb(struct sk_buff *skb); | |
774 | void __kfree_skb(struct sk_buff *skb); | |
d7e8883c | 775 | extern struct kmem_cache *skbuff_head_cache; |
bad43ca8 | 776 | |
7965bd4d JP |
777 | void kfree_skb_partial(struct sk_buff *skb, bool head_stolen); |
778 | bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, | |
779 | bool *fragstolen, int *delta_truesize); | |
bad43ca8 | 780 | |
7965bd4d JP |
781 | struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags, |
782 | int node); | |
783 | struct sk_buff *build_skb(void *data, unsigned int frag_size); | |
d179cd12 | 784 | static inline struct sk_buff *alloc_skb(unsigned int size, |
dd0fc66f | 785 | gfp_t priority) |
d179cd12 | 786 | { |
564824b0 | 787 | return __alloc_skb(size, priority, 0, NUMA_NO_NODE); |
d179cd12 DM |
788 | } |
789 | ||
2e4e4410 ED |
790 | struct sk_buff *alloc_skb_with_frags(unsigned long header_len, |
791 | unsigned long data_len, | |
792 | int max_page_order, | |
793 | int *errcode, | |
794 | gfp_t gfp_mask); | |
795 | ||
d0bf4a9e ED |
796 | /* Layout of fast clones : [skb1][skb2][fclone_ref] */ |
797 | struct sk_buff_fclones { | |
798 | struct sk_buff skb1; | |
799 | ||
800 | struct sk_buff skb2; | |
801 | ||
802 | atomic_t fclone_ref; | |
803 | }; | |
804 | ||
805 | /** | |
806 | * skb_fclone_busy - check if fclone is busy | |
807 | * @skb: buffer | |
808 | * | |
809 | * Returns true is skb is a fast clone, and its clone is not freed. | |
39bb5e62 ED |
810 | * Some drivers call skb_orphan() in their ndo_start_xmit(), |
811 | * so we also check that this didnt happen. | |
d0bf4a9e | 812 | */ |
39bb5e62 ED |
813 | static inline bool skb_fclone_busy(const struct sock *sk, |
814 | const struct sk_buff *skb) | |
d0bf4a9e ED |
815 | { |
816 | const struct sk_buff_fclones *fclones; | |
817 | ||
818 | fclones = container_of(skb, struct sk_buff_fclones, skb1); | |
819 | ||
820 | return skb->fclone == SKB_FCLONE_ORIG && | |
39bb5e62 ED |
821 | fclones->skb2.fclone == SKB_FCLONE_CLONE && |
822 | fclones->skb2.sk == sk; | |
d0bf4a9e ED |
823 | } |
824 | ||
d179cd12 | 825 | static inline struct sk_buff *alloc_skb_fclone(unsigned int size, |
dd0fc66f | 826 | gfp_t priority) |
d179cd12 | 827 | { |
c93bdd0e | 828 | return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE); |
d179cd12 DM |
829 | } |
830 | ||
7965bd4d | 831 | struct sk_buff *__alloc_skb_head(gfp_t priority, int node); |
0ebd0ac5 PM |
832 | static inline struct sk_buff *alloc_skb_head(gfp_t priority) |
833 | { | |
834 | return __alloc_skb_head(priority, -1); | |
835 | } | |
836 | ||
7965bd4d JP |
837 | struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src); |
838 | int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask); | |
839 | struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority); | |
840 | struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority); | |
bad93e9d OP |
841 | struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom, |
842 | gfp_t gfp_mask, bool fclone); | |
843 | static inline struct sk_buff *__pskb_copy(struct sk_buff *skb, int headroom, | |
844 | gfp_t gfp_mask) | |
845 | { | |
846 | return __pskb_copy_fclone(skb, headroom, gfp_mask, false); | |
847 | } | |
7965bd4d JP |
848 | |
849 | int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, gfp_t gfp_mask); | |
850 | struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, | |
851 | unsigned int headroom); | |
852 | struct sk_buff *skb_copy_expand(const struct sk_buff *skb, int newheadroom, | |
853 | int newtailroom, gfp_t priority); | |
25a91d8d FD |
854 | int skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg, |
855 | int offset, int len); | |
7965bd4d JP |
856 | int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, |
857 | int len); | |
858 | int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer); | |
859 | int skb_pad(struct sk_buff *skb, int pad); | |
ead2ceb0 | 860 | #define dev_kfree_skb(a) consume_skb(a) |
1da177e4 | 861 | |
7965bd4d JP |
862 | int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, |
863 | int getfrag(void *from, char *to, int offset, | |
864 | int len, int odd, struct sk_buff *skb), | |
865 | void *from, int length); | |
e89e9cf5 | 866 | |
d94d9fee | 867 | struct skb_seq_state { |
677e90ed TG |
868 | __u32 lower_offset; |
869 | __u32 upper_offset; | |
870 | __u32 frag_idx; | |
871 | __u32 stepped_offset; | |
872 | struct sk_buff *root_skb; | |
873 | struct sk_buff *cur_skb; | |
874 | __u8 *frag_data; | |
875 | }; | |
876 | ||
7965bd4d JP |
877 | void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, |
878 | unsigned int to, struct skb_seq_state *st); | |
879 | unsigned int skb_seq_read(unsigned int consumed, const u8 **data, | |
880 | struct skb_seq_state *st); | |
881 | void skb_abort_seq_read(struct skb_seq_state *st); | |
677e90ed | 882 | |
7965bd4d JP |
883 | unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, |
884 | unsigned int to, struct ts_config *config, | |
885 | struct ts_state *state); | |
3fc7e8a6 | 886 | |
09323cc4 TH |
887 | /* |
888 | * Packet hash types specify the type of hash in skb_set_hash. | |
889 | * | |
890 | * Hash types refer to the protocol layer addresses which are used to | |
891 | * construct a packet's hash. The hashes are used to differentiate or identify | |
892 | * flows of the protocol layer for the hash type. Hash types are either | |
893 | * layer-2 (L2), layer-3 (L3), or layer-4 (L4). | |
894 | * | |
895 | * Properties of hashes: | |
896 | * | |
897 | * 1) Two packets in different flows have different hash values | |
898 | * 2) Two packets in the same flow should have the same hash value | |
899 | * | |
900 | * A hash at a higher layer is considered to be more specific. A driver should | |
901 | * set the most specific hash possible. | |
902 | * | |
903 | * A driver cannot indicate a more specific hash than the layer at which a hash | |
904 | * was computed. For instance an L3 hash cannot be set as an L4 hash. | |
905 | * | |
906 | * A driver may indicate a hash level which is less specific than the | |
907 | * actual layer the hash was computed on. For instance, a hash computed | |
908 | * at L4 may be considered an L3 hash. This should only be done if the | |
909 | * driver can't unambiguously determine that the HW computed the hash at | |
910 | * the higher layer. Note that the "should" in the second property above | |
911 | * permits this. | |
912 | */ | |
913 | enum pkt_hash_types { | |
914 | PKT_HASH_TYPE_NONE, /* Undefined type */ | |
915 | PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */ | |
916 | PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */ | |
917 | PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */ | |
918 | }; | |
919 | ||
920 | static inline void | |
921 | skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type) | |
922 | { | |
61b905da | 923 | skb->l4_hash = (type == PKT_HASH_TYPE_L4); |
a3b18ddb | 924 | skb->sw_hash = 0; |
61b905da | 925 | skb->hash = hash; |
09323cc4 TH |
926 | } |
927 | ||
3958afa1 TH |
928 | void __skb_get_hash(struct sk_buff *skb); |
929 | static inline __u32 skb_get_hash(struct sk_buff *skb) | |
bfb564e7 | 930 | { |
a3b18ddb | 931 | if (!skb->l4_hash && !skb->sw_hash) |
3958afa1 | 932 | __skb_get_hash(skb); |
bfb564e7 | 933 | |
61b905da | 934 | return skb->hash; |
bfb564e7 KK |
935 | } |
936 | ||
57bdf7f4 TH |
937 | static inline __u32 skb_get_hash_raw(const struct sk_buff *skb) |
938 | { | |
61b905da | 939 | return skb->hash; |
57bdf7f4 TH |
940 | } |
941 | ||
7539fadc TH |
942 | static inline void skb_clear_hash(struct sk_buff *skb) |
943 | { | |
61b905da | 944 | skb->hash = 0; |
a3b18ddb | 945 | skb->sw_hash = 0; |
61b905da | 946 | skb->l4_hash = 0; |
7539fadc TH |
947 | } |
948 | ||
949 | static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb) | |
950 | { | |
61b905da | 951 | if (!skb->l4_hash) |
7539fadc TH |
952 | skb_clear_hash(skb); |
953 | } | |
954 | ||
3df7a74e TH |
955 | static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from) |
956 | { | |
61b905da | 957 | to->hash = from->hash; |
a3b18ddb | 958 | to->sw_hash = from->sw_hash; |
61b905da | 959 | to->l4_hash = from->l4_hash; |
3df7a74e TH |
960 | }; |
961 | ||
4305b541 ACM |
962 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
963 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
964 | { | |
965 | return skb->head + skb->end; | |
966 | } | |
ec47ea82 AD |
967 | |
968 | static inline unsigned int skb_end_offset(const struct sk_buff *skb) | |
969 | { | |
970 | return skb->end; | |
971 | } | |
4305b541 ACM |
972 | #else |
973 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) | |
974 | { | |
975 | return skb->end; | |
976 | } | |
ec47ea82 AD |
977 | |
978 | static inline unsigned int skb_end_offset(const struct sk_buff *skb) | |
979 | { | |
980 | return skb->end - skb->head; | |
981 | } | |
4305b541 ACM |
982 | #endif |
983 | ||
1da177e4 | 984 | /* Internal */ |
4305b541 | 985 | #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) |
1da177e4 | 986 | |
ac45f602 PO |
987 | static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb) |
988 | { | |
989 | return &skb_shinfo(skb)->hwtstamps; | |
990 | } | |
991 | ||
1da177e4 LT |
992 | /** |
993 | * skb_queue_empty - check if a queue is empty | |
994 | * @list: queue head | |
995 | * | |
996 | * Returns true if the queue is empty, false otherwise. | |
997 | */ | |
998 | static inline int skb_queue_empty(const struct sk_buff_head *list) | |
999 | { | |
fd44b93c | 1000 | return list->next == (const struct sk_buff *) list; |
1da177e4 LT |
1001 | } |
1002 | ||
fc7ebb21 DM |
1003 | /** |
1004 | * skb_queue_is_last - check if skb is the last entry in the queue | |
1005 | * @list: queue head | |
1006 | * @skb: buffer | |
1007 | * | |
1008 | * Returns true if @skb is the last buffer on the list. | |
1009 | */ | |
1010 | static inline bool skb_queue_is_last(const struct sk_buff_head *list, | |
1011 | const struct sk_buff *skb) | |
1012 | { | |
fd44b93c | 1013 | return skb->next == (const struct sk_buff *) list; |
fc7ebb21 DM |
1014 | } |
1015 | ||
832d11c5 IJ |
1016 | /** |
1017 | * skb_queue_is_first - check if skb is the first entry in the queue | |
1018 | * @list: queue head | |
1019 | * @skb: buffer | |
1020 | * | |
1021 | * Returns true if @skb is the first buffer on the list. | |
1022 | */ | |
1023 | static inline bool skb_queue_is_first(const struct sk_buff_head *list, | |
1024 | const struct sk_buff *skb) | |
1025 | { | |
fd44b93c | 1026 | return skb->prev == (const struct sk_buff *) list; |
832d11c5 IJ |
1027 | } |
1028 | ||
249c8b42 DM |
1029 | /** |
1030 | * skb_queue_next - return the next packet in the queue | |
1031 | * @list: queue head | |
1032 | * @skb: current buffer | |
1033 | * | |
1034 | * Return the next packet in @list after @skb. It is only valid to | |
1035 | * call this if skb_queue_is_last() evaluates to false. | |
1036 | */ | |
1037 | static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list, | |
1038 | const struct sk_buff *skb) | |
1039 | { | |
1040 | /* This BUG_ON may seem severe, but if we just return then we | |
1041 | * are going to dereference garbage. | |
1042 | */ | |
1043 | BUG_ON(skb_queue_is_last(list, skb)); | |
1044 | return skb->next; | |
1045 | } | |
1046 | ||
832d11c5 IJ |
1047 | /** |
1048 | * skb_queue_prev - return the prev packet in the queue | |
1049 | * @list: queue head | |
1050 | * @skb: current buffer | |
1051 | * | |
1052 | * Return the prev packet in @list before @skb. It is only valid to | |
1053 | * call this if skb_queue_is_first() evaluates to false. | |
1054 | */ | |
1055 | static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list, | |
1056 | const struct sk_buff *skb) | |
1057 | { | |
1058 | /* This BUG_ON may seem severe, but if we just return then we | |
1059 | * are going to dereference garbage. | |
1060 | */ | |
1061 | BUG_ON(skb_queue_is_first(list, skb)); | |
1062 | return skb->prev; | |
1063 | } | |
1064 | ||
1da177e4 LT |
1065 | /** |
1066 | * skb_get - reference buffer | |
1067 | * @skb: buffer to reference | |
1068 | * | |
1069 | * Makes another reference to a socket buffer and returns a pointer | |
1070 | * to the buffer. | |
1071 | */ | |
1072 | static inline struct sk_buff *skb_get(struct sk_buff *skb) | |
1073 | { | |
1074 | atomic_inc(&skb->users); | |
1075 | return skb; | |
1076 | } | |
1077 | ||
1078 | /* | |
1079 | * If users == 1, we are the only owner and are can avoid redundant | |
1080 | * atomic change. | |
1081 | */ | |
1082 | ||
1da177e4 LT |
1083 | /** |
1084 | * skb_cloned - is the buffer a clone | |
1085 | * @skb: buffer to check | |
1086 | * | |
1087 | * Returns true if the buffer was generated with skb_clone() and is | |
1088 | * one of multiple shared copies of the buffer. Cloned buffers are | |
1089 | * shared data so must not be written to under normal circumstances. | |
1090 | */ | |
1091 | static inline int skb_cloned(const struct sk_buff *skb) | |
1092 | { | |
1093 | return skb->cloned && | |
1094 | (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; | |
1095 | } | |
1096 | ||
14bbd6a5 PS |
1097 | static inline int skb_unclone(struct sk_buff *skb, gfp_t pri) |
1098 | { | |
1099 | might_sleep_if(pri & __GFP_WAIT); | |
1100 | ||
1101 | if (skb_cloned(skb)) | |
1102 | return pskb_expand_head(skb, 0, 0, pri); | |
1103 | ||
1104 | return 0; | |
1105 | } | |
1106 | ||
1da177e4 LT |
1107 | /** |
1108 | * skb_header_cloned - is the header a clone | |
1109 | * @skb: buffer to check | |
1110 | * | |
1111 | * Returns true if modifying the header part of the buffer requires | |
1112 | * the data to be copied. | |
1113 | */ | |
1114 | static inline int skb_header_cloned(const struct sk_buff *skb) | |
1115 | { | |
1116 | int dataref; | |
1117 | ||
1118 | if (!skb->cloned) | |
1119 | return 0; | |
1120 | ||
1121 | dataref = atomic_read(&skb_shinfo(skb)->dataref); | |
1122 | dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); | |
1123 | return dataref != 1; | |
1124 | } | |
1125 | ||
1126 | /** | |
1127 | * skb_header_release - release reference to header | |
1128 | * @skb: buffer to operate on | |
1129 | * | |
1130 | * Drop a reference to the header part of the buffer. This is done | |
1131 | * by acquiring a payload reference. You must not read from the header | |
1132 | * part of skb->data after this. | |
f4a775d1 | 1133 | * Note : Check if you can use __skb_header_release() instead. |
1da177e4 LT |
1134 | */ |
1135 | static inline void skb_header_release(struct sk_buff *skb) | |
1136 | { | |
1137 | BUG_ON(skb->nohdr); | |
1138 | skb->nohdr = 1; | |
1139 | atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); | |
1140 | } | |
1141 | ||
f4a775d1 ED |
1142 | /** |
1143 | * __skb_header_release - release reference to header | |
1144 | * @skb: buffer to operate on | |
1145 | * | |
1146 | * Variant of skb_header_release() assuming skb is private to caller. | |
1147 | * We can avoid one atomic operation. | |
1148 | */ | |
1149 | static inline void __skb_header_release(struct sk_buff *skb) | |
1150 | { | |
1151 | skb->nohdr = 1; | |
1152 | atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT)); | |
1153 | } | |
1154 | ||
1155 | ||
1da177e4 LT |
1156 | /** |
1157 | * skb_shared - is the buffer shared | |
1158 | * @skb: buffer to check | |
1159 | * | |
1160 | * Returns true if more than one person has a reference to this | |
1161 | * buffer. | |
1162 | */ | |
1163 | static inline int skb_shared(const struct sk_buff *skb) | |
1164 | { | |
1165 | return atomic_read(&skb->users) != 1; | |
1166 | } | |
1167 | ||
1168 | /** | |
1169 | * skb_share_check - check if buffer is shared and if so clone it | |
1170 | * @skb: buffer to check | |
1171 | * @pri: priority for memory allocation | |
1172 | * | |
1173 | * If the buffer is shared the buffer is cloned and the old copy | |
1174 | * drops a reference. A new clone with a single reference is returned. | |
1175 | * If the buffer is not shared the original buffer is returned. When | |
1176 | * being called from interrupt status or with spinlocks held pri must | |
1177 | * be GFP_ATOMIC. | |
1178 | * | |
1179 | * NULL is returned on a memory allocation failure. | |
1180 | */ | |
47061bc4 | 1181 | static inline struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri) |
1da177e4 LT |
1182 | { |
1183 | might_sleep_if(pri & __GFP_WAIT); | |
1184 | if (skb_shared(skb)) { | |
1185 | struct sk_buff *nskb = skb_clone(skb, pri); | |
47061bc4 ED |
1186 | |
1187 | if (likely(nskb)) | |
1188 | consume_skb(skb); | |
1189 | else | |
1190 | kfree_skb(skb); | |
1da177e4 LT |
1191 | skb = nskb; |
1192 | } | |
1193 | return skb; | |
1194 | } | |
1195 | ||
1196 | /* | |
1197 | * Copy shared buffers into a new sk_buff. We effectively do COW on | |
1198 | * packets to handle cases where we have a local reader and forward | |
1199 | * and a couple of other messy ones. The normal one is tcpdumping | |
1200 | * a packet thats being forwarded. | |
1201 | */ | |
1202 | ||
1203 | /** | |
1204 | * skb_unshare - make a copy of a shared buffer | |
1205 | * @skb: buffer to check | |
1206 | * @pri: priority for memory allocation | |
1207 | * | |
1208 | * If the socket buffer is a clone then this function creates a new | |
1209 | * copy of the data, drops a reference count on the old copy and returns | |
1210 | * the new copy with the reference count at 1. If the buffer is not a clone | |
1211 | * the original buffer is returned. When called with a spinlock held or | |
1212 | * from interrupt state @pri must be %GFP_ATOMIC | |
1213 | * | |
1214 | * %NULL is returned on a memory allocation failure. | |
1215 | */ | |
e2bf521d | 1216 | static inline struct sk_buff *skb_unshare(struct sk_buff *skb, |
dd0fc66f | 1217 | gfp_t pri) |
1da177e4 LT |
1218 | { |
1219 | might_sleep_if(pri & __GFP_WAIT); | |
1220 | if (skb_cloned(skb)) { | |
1221 | struct sk_buff *nskb = skb_copy(skb, pri); | |
31eff81e AA |
1222 | |
1223 | /* Free our shared copy */ | |
1224 | if (likely(nskb)) | |
1225 | consume_skb(skb); | |
1226 | else | |
1227 | kfree_skb(skb); | |
1da177e4 LT |
1228 | skb = nskb; |
1229 | } | |
1230 | return skb; | |
1231 | } | |
1232 | ||
1233 | /** | |
1a5778aa | 1234 | * skb_peek - peek at the head of an &sk_buff_head |
1da177e4 LT |
1235 | * @list_: list to peek at |
1236 | * | |
1237 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
1238 | * be careful with this one. A peek leaves the buffer on the | |
1239 | * list and someone else may run off with it. You must hold | |
1240 | * the appropriate locks or have a private queue to do this. | |
1241 | * | |
1242 | * Returns %NULL for an empty list or a pointer to the head element. | |
1243 | * The reference count is not incremented and the reference is therefore | |
1244 | * volatile. Use with caution. | |
1245 | */ | |
05bdd2f1 | 1246 | static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_) |
1da177e4 | 1247 | { |
18d07000 ED |
1248 | struct sk_buff *skb = list_->next; |
1249 | ||
1250 | if (skb == (struct sk_buff *)list_) | |
1251 | skb = NULL; | |
1252 | return skb; | |
1da177e4 LT |
1253 | } |
1254 | ||
da5ef6e5 PE |
1255 | /** |
1256 | * skb_peek_next - peek skb following the given one from a queue | |
1257 | * @skb: skb to start from | |
1258 | * @list_: list to peek at | |
1259 | * | |
1260 | * Returns %NULL when the end of the list is met or a pointer to the | |
1261 | * next element. The reference count is not incremented and the | |
1262 | * reference is therefore volatile. Use with caution. | |
1263 | */ | |
1264 | static inline struct sk_buff *skb_peek_next(struct sk_buff *skb, | |
1265 | const struct sk_buff_head *list_) | |
1266 | { | |
1267 | struct sk_buff *next = skb->next; | |
18d07000 | 1268 | |
da5ef6e5 PE |
1269 | if (next == (struct sk_buff *)list_) |
1270 | next = NULL; | |
1271 | return next; | |
1272 | } | |
1273 | ||
1da177e4 | 1274 | /** |
1a5778aa | 1275 | * skb_peek_tail - peek at the tail of an &sk_buff_head |
1da177e4 LT |
1276 | * @list_: list to peek at |
1277 | * | |
1278 | * Peek an &sk_buff. Unlike most other operations you _MUST_ | |
1279 | * be careful with this one. A peek leaves the buffer on the | |
1280 | * list and someone else may run off with it. You must hold | |
1281 | * the appropriate locks or have a private queue to do this. | |
1282 | * | |
1283 | * Returns %NULL for an empty list or a pointer to the tail element. | |
1284 | * The reference count is not incremented and the reference is therefore | |
1285 | * volatile. Use with caution. | |
1286 | */ | |
05bdd2f1 | 1287 | static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_) |
1da177e4 | 1288 | { |
18d07000 ED |
1289 | struct sk_buff *skb = list_->prev; |
1290 | ||
1291 | if (skb == (struct sk_buff *)list_) | |
1292 | skb = NULL; | |
1293 | return skb; | |
1294 | ||
1da177e4 LT |
1295 | } |
1296 | ||
1297 | /** | |
1298 | * skb_queue_len - get queue length | |
1299 | * @list_: list to measure | |
1300 | * | |
1301 | * Return the length of an &sk_buff queue. | |
1302 | */ | |
1303 | static inline __u32 skb_queue_len(const struct sk_buff_head *list_) | |
1304 | { | |
1305 | return list_->qlen; | |
1306 | } | |
1307 | ||
67fed459 DM |
1308 | /** |
1309 | * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head | |
1310 | * @list: queue to initialize | |
1311 | * | |
1312 | * This initializes only the list and queue length aspects of | |
1313 | * an sk_buff_head object. This allows to initialize the list | |
1314 | * aspects of an sk_buff_head without reinitializing things like | |
1315 | * the spinlock. It can also be used for on-stack sk_buff_head | |
1316 | * objects where the spinlock is known to not be used. | |
1317 | */ | |
1318 | static inline void __skb_queue_head_init(struct sk_buff_head *list) | |
1319 | { | |
1320 | list->prev = list->next = (struct sk_buff *)list; | |
1321 | list->qlen = 0; | |
1322 | } | |
1323 | ||
76f10ad0 AV |
1324 | /* |
1325 | * This function creates a split out lock class for each invocation; | |
1326 | * this is needed for now since a whole lot of users of the skb-queue | |
1327 | * infrastructure in drivers have different locking usage (in hardirq) | |
1328 | * than the networking core (in softirq only). In the long run either the | |
1329 | * network layer or drivers should need annotation to consolidate the | |
1330 | * main types of usage into 3 classes. | |
1331 | */ | |
1da177e4 LT |
1332 | static inline void skb_queue_head_init(struct sk_buff_head *list) |
1333 | { | |
1334 | spin_lock_init(&list->lock); | |
67fed459 | 1335 | __skb_queue_head_init(list); |
1da177e4 LT |
1336 | } |
1337 | ||
c2ecba71 PE |
1338 | static inline void skb_queue_head_init_class(struct sk_buff_head *list, |
1339 | struct lock_class_key *class) | |
1340 | { | |
1341 | skb_queue_head_init(list); | |
1342 | lockdep_set_class(&list->lock, class); | |
1343 | } | |
1344 | ||
1da177e4 | 1345 | /* |
bf299275 | 1346 | * Insert an sk_buff on a list. |
1da177e4 LT |
1347 | * |
1348 | * The "__skb_xxxx()" functions are the non-atomic ones that | |
1349 | * can only be called with interrupts disabled. | |
1350 | */ | |
7965bd4d JP |
1351 | void skb_insert(struct sk_buff *old, struct sk_buff *newsk, |
1352 | struct sk_buff_head *list); | |
bf299275 GR |
1353 | static inline void __skb_insert(struct sk_buff *newsk, |
1354 | struct sk_buff *prev, struct sk_buff *next, | |
1355 | struct sk_buff_head *list) | |
1356 | { | |
1357 | newsk->next = next; | |
1358 | newsk->prev = prev; | |
1359 | next->prev = prev->next = newsk; | |
1360 | list->qlen++; | |
1361 | } | |
1da177e4 | 1362 | |
67fed459 DM |
1363 | static inline void __skb_queue_splice(const struct sk_buff_head *list, |
1364 | struct sk_buff *prev, | |
1365 | struct sk_buff *next) | |
1366 | { | |
1367 | struct sk_buff *first = list->next; | |
1368 | struct sk_buff *last = list->prev; | |
1369 | ||
1370 | first->prev = prev; | |
1371 | prev->next = first; | |
1372 | ||
1373 | last->next = next; | |
1374 | next->prev = last; | |
1375 | } | |
1376 | ||
1377 | /** | |
1378 | * skb_queue_splice - join two skb lists, this is designed for stacks | |
1379 | * @list: the new list to add | |
1380 | * @head: the place to add it in the first list | |
1381 | */ | |
1382 | static inline void skb_queue_splice(const struct sk_buff_head *list, | |
1383 | struct sk_buff_head *head) | |
1384 | { | |
1385 | if (!skb_queue_empty(list)) { | |
1386 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
1d4a31dd | 1387 | head->qlen += list->qlen; |
67fed459 DM |
1388 | } |
1389 | } | |
1390 | ||
1391 | /** | |
d9619496 | 1392 | * skb_queue_splice_init - join two skb lists and reinitialise the emptied list |
67fed459 DM |
1393 | * @list: the new list to add |
1394 | * @head: the place to add it in the first list | |
1395 | * | |
1396 | * The list at @list is reinitialised | |
1397 | */ | |
1398 | static inline void skb_queue_splice_init(struct sk_buff_head *list, | |
1399 | struct sk_buff_head *head) | |
1400 | { | |
1401 | if (!skb_queue_empty(list)) { | |
1402 | __skb_queue_splice(list, (struct sk_buff *) head, head->next); | |
1d4a31dd | 1403 | head->qlen += list->qlen; |
67fed459 DM |
1404 | __skb_queue_head_init(list); |
1405 | } | |
1406 | } | |
1407 | ||
1408 | /** | |
1409 | * skb_queue_splice_tail - join two skb lists, each list being a queue | |
1410 | * @list: the new list to add | |
1411 | * @head: the place to add it in the first list | |
1412 | */ | |
1413 | static inline void skb_queue_splice_tail(const struct sk_buff_head *list, | |
1414 | struct sk_buff_head *head) | |
1415 | { | |
1416 | if (!skb_queue_empty(list)) { | |
1417 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
1d4a31dd | 1418 | head->qlen += list->qlen; |
67fed459 DM |
1419 | } |
1420 | } | |
1421 | ||
1422 | /** | |
d9619496 | 1423 | * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list |
67fed459 DM |
1424 | * @list: the new list to add |
1425 | * @head: the place to add it in the first list | |
1426 | * | |
1427 | * Each of the lists is a queue. | |
1428 | * The list at @list is reinitialised | |
1429 | */ | |
1430 | static inline void skb_queue_splice_tail_init(struct sk_buff_head *list, | |
1431 | struct sk_buff_head *head) | |
1432 | { | |
1433 | if (!skb_queue_empty(list)) { | |
1434 | __skb_queue_splice(list, head->prev, (struct sk_buff *) head); | |
1d4a31dd | 1435 | head->qlen += list->qlen; |
67fed459 DM |
1436 | __skb_queue_head_init(list); |
1437 | } | |
1438 | } | |
1439 | ||
1da177e4 | 1440 | /** |
300ce174 | 1441 | * __skb_queue_after - queue a buffer at the list head |
1da177e4 | 1442 | * @list: list to use |
300ce174 | 1443 | * @prev: place after this buffer |
1da177e4 LT |
1444 | * @newsk: buffer to queue |
1445 | * | |
300ce174 | 1446 | * Queue a buffer int the middle of a list. This function takes no locks |
1da177e4 LT |
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 | */ | |
300ce174 SH |
1451 | static inline void __skb_queue_after(struct sk_buff_head *list, |
1452 | struct sk_buff *prev, | |
1453 | struct sk_buff *newsk) | |
1da177e4 | 1454 | { |
bf299275 | 1455 | __skb_insert(newsk, prev, prev->next, list); |
1da177e4 LT |
1456 | } |
1457 | ||
7965bd4d JP |
1458 | void skb_append(struct sk_buff *old, struct sk_buff *newsk, |
1459 | struct sk_buff_head *list); | |
7de6c033 | 1460 | |
f5572855 GR |
1461 | static inline void __skb_queue_before(struct sk_buff_head *list, |
1462 | struct sk_buff *next, | |
1463 | struct sk_buff *newsk) | |
1464 | { | |
1465 | __skb_insert(newsk, next->prev, next, list); | |
1466 | } | |
1467 | ||
300ce174 SH |
1468 | /** |
1469 | * __skb_queue_head - queue a buffer at the list head | |
1470 | * @list: list to use | |
1471 | * @newsk: buffer to queue | |
1472 | * | |
1473 | * Queue a buffer at the start of a list. This function takes no locks | |
1474 | * and you must therefore hold required locks before calling it. | |
1475 | * | |
1476 | * A buffer cannot be placed on two lists at the same time. | |
1477 | */ | |
7965bd4d | 1478 | void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); |
300ce174 SH |
1479 | static inline void __skb_queue_head(struct sk_buff_head *list, |
1480 | struct sk_buff *newsk) | |
1481 | { | |
1482 | __skb_queue_after(list, (struct sk_buff *)list, newsk); | |
1483 | } | |
1484 | ||
1da177e4 LT |
1485 | /** |
1486 | * __skb_queue_tail - queue a buffer at the list tail | |
1487 | * @list: list to use | |
1488 | * @newsk: buffer to queue | |
1489 | * | |
1490 | * Queue a buffer at the end of a list. This function takes no locks | |
1491 | * and you must therefore hold required locks before calling it. | |
1492 | * | |
1493 | * A buffer cannot be placed on two lists at the same time. | |
1494 | */ | |
7965bd4d | 1495 | void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); |
1da177e4 LT |
1496 | static inline void __skb_queue_tail(struct sk_buff_head *list, |
1497 | struct sk_buff *newsk) | |
1498 | { | |
f5572855 | 1499 | __skb_queue_before(list, (struct sk_buff *)list, newsk); |
1da177e4 LT |
1500 | } |
1501 | ||
1da177e4 LT |
1502 | /* |
1503 | * remove sk_buff from list. _Must_ be called atomically, and with | |
1504 | * the list known.. | |
1505 | */ | |
7965bd4d | 1506 | void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); |
1da177e4 LT |
1507 | static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) |
1508 | { | |
1509 | struct sk_buff *next, *prev; | |
1510 | ||
1511 | list->qlen--; | |
1512 | next = skb->next; | |
1513 | prev = skb->prev; | |
1514 | skb->next = skb->prev = NULL; | |
1da177e4 LT |
1515 | next->prev = prev; |
1516 | prev->next = next; | |
1517 | } | |
1518 | ||
f525c06d GR |
1519 | /** |
1520 | * __skb_dequeue - remove from the head of the queue | |
1521 | * @list: list to dequeue from | |
1522 | * | |
1523 | * Remove the head of the list. This function does not take any locks | |
1524 | * so must be used with appropriate locks held only. The head item is | |
1525 | * returned or %NULL if the list is empty. | |
1526 | */ | |
7965bd4d | 1527 | struct sk_buff *skb_dequeue(struct sk_buff_head *list); |
f525c06d GR |
1528 | static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) |
1529 | { | |
1530 | struct sk_buff *skb = skb_peek(list); | |
1531 | if (skb) | |
1532 | __skb_unlink(skb, list); | |
1533 | return skb; | |
1534 | } | |
1da177e4 LT |
1535 | |
1536 | /** | |
1537 | * __skb_dequeue_tail - remove from the tail of the queue | |
1538 | * @list: list to dequeue from | |
1539 | * | |
1540 | * Remove the tail of the list. This function does not take any locks | |
1541 | * so must be used with appropriate locks held only. The tail item is | |
1542 | * returned or %NULL if the list is empty. | |
1543 | */ | |
7965bd4d | 1544 | struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); |
1da177e4 LT |
1545 | static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) |
1546 | { | |
1547 | struct sk_buff *skb = skb_peek_tail(list); | |
1548 | if (skb) | |
1549 | __skb_unlink(skb, list); | |
1550 | return skb; | |
1551 | } | |
1552 | ||
1553 | ||
bdcc0924 | 1554 | static inline bool skb_is_nonlinear(const struct sk_buff *skb) |
1da177e4 LT |
1555 | { |
1556 | return skb->data_len; | |
1557 | } | |
1558 | ||
1559 | static inline unsigned int skb_headlen(const struct sk_buff *skb) | |
1560 | { | |
1561 | return skb->len - skb->data_len; | |
1562 | } | |
1563 | ||
1564 | static inline int skb_pagelen(const struct sk_buff *skb) | |
1565 | { | |
1566 | int i, len = 0; | |
1567 | ||
1568 | for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) | |
9e903e08 | 1569 | len += skb_frag_size(&skb_shinfo(skb)->frags[i]); |
1da177e4 LT |
1570 | return len + skb_headlen(skb); |
1571 | } | |
1572 | ||
131ea667 IC |
1573 | /** |
1574 | * __skb_fill_page_desc - initialise a paged fragment in an skb | |
1575 | * @skb: buffer containing fragment to be initialised | |
1576 | * @i: paged fragment index to initialise | |
1577 | * @page: the page to use for this fragment | |
1578 | * @off: the offset to the data with @page | |
1579 | * @size: the length of the data | |
1580 | * | |
1581 | * Initialises the @i'th fragment of @skb to point to &size bytes at | |
1582 | * offset @off within @page. | |
1583 | * | |
1584 | * Does not take any additional reference on the fragment. | |
1585 | */ | |
1586 | static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, | |
1587 | struct page *page, int off, int size) | |
1da177e4 LT |
1588 | { |
1589 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; | |
1590 | ||
c48a11c7 MG |
1591 | /* |
1592 | * Propagate page->pfmemalloc to the skb if we can. The problem is | |
1593 | * that not all callers have unique ownership of the page. If | |
1594 | * pfmemalloc is set, we check the mapping as a mapping implies | |
1595 | * page->index is set (index and pfmemalloc share space). | |
1596 | * If it's a valid mapping, we cannot use page->pfmemalloc but we | |
1597 | * do not lose pfmemalloc information as the pages would not be | |
1598 | * allocated using __GFP_MEMALLOC. | |
1599 | */ | |
a8605c60 | 1600 | frag->page.p = page; |
1da177e4 | 1601 | frag->page_offset = off; |
9e903e08 | 1602 | skb_frag_size_set(frag, size); |
cca7af38 PE |
1603 | |
1604 | page = compound_head(page); | |
1605 | if (page->pfmemalloc && !page->mapping) | |
1606 | skb->pfmemalloc = true; | |
131ea667 IC |
1607 | } |
1608 | ||
1609 | /** | |
1610 | * skb_fill_page_desc - initialise a paged fragment in an skb | |
1611 | * @skb: buffer containing fragment to be initialised | |
1612 | * @i: paged fragment index to initialise | |
1613 | * @page: the page to use for this fragment | |
1614 | * @off: the offset to the data with @page | |
1615 | * @size: the length of the data | |
1616 | * | |
1617 | * As per __skb_fill_page_desc() -- initialises the @i'th fragment of | |
bc32383c | 1618 | * @skb to point to @size bytes at offset @off within @page. In |
131ea667 IC |
1619 | * addition updates @skb such that @i is the last fragment. |
1620 | * | |
1621 | * Does not take any additional reference on the fragment. | |
1622 | */ | |
1623 | static inline void skb_fill_page_desc(struct sk_buff *skb, int i, | |
1624 | struct page *page, int off, int size) | |
1625 | { | |
1626 | __skb_fill_page_desc(skb, i, page, off, size); | |
1da177e4 LT |
1627 | skb_shinfo(skb)->nr_frags = i + 1; |
1628 | } | |
1629 | ||
7965bd4d JP |
1630 | void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, |
1631 | int size, unsigned int truesize); | |
654bed16 | 1632 | |
f8e617e1 JW |
1633 | void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, |
1634 | unsigned int truesize); | |
1635 | ||
1da177e4 | 1636 | #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) |
21dc3301 | 1637 | #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb)) |
1da177e4 LT |
1638 | #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) |
1639 | ||
27a884dc ACM |
1640 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
1641 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
1642 | { | |
1643 | return skb->head + skb->tail; | |
1644 | } | |
1645 | ||
1646 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
1647 | { | |
1648 | skb->tail = skb->data - skb->head; | |
1649 | } | |
1650 | ||
1651 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
1652 | { | |
1653 | skb_reset_tail_pointer(skb); | |
1654 | skb->tail += offset; | |
1655 | } | |
7cc46190 | 1656 | |
27a884dc ACM |
1657 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ |
1658 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) | |
1659 | { | |
1660 | return skb->tail; | |
1661 | } | |
1662 | ||
1663 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) | |
1664 | { | |
1665 | skb->tail = skb->data; | |
1666 | } | |
1667 | ||
1668 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) | |
1669 | { | |
1670 | skb->tail = skb->data + offset; | |
1671 | } | |
4305b541 | 1672 | |
27a884dc ACM |
1673 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ |
1674 | ||
1da177e4 LT |
1675 | /* |
1676 | * Add data to an sk_buff | |
1677 | */ | |
0c7ddf36 | 1678 | unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len); |
7965bd4d | 1679 | unsigned char *skb_put(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1680 | static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) |
1681 | { | |
27a884dc | 1682 | unsigned char *tmp = skb_tail_pointer(skb); |
1da177e4 LT |
1683 | SKB_LINEAR_ASSERT(skb); |
1684 | skb->tail += len; | |
1685 | skb->len += len; | |
1686 | return tmp; | |
1687 | } | |
1688 | ||
7965bd4d | 1689 | unsigned char *skb_push(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1690 | static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) |
1691 | { | |
1692 | skb->data -= len; | |
1693 | skb->len += len; | |
1694 | return skb->data; | |
1695 | } | |
1696 | ||
7965bd4d | 1697 | unsigned char *skb_pull(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
1698 | static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) |
1699 | { | |
1700 | skb->len -= len; | |
1701 | BUG_ON(skb->len < skb->data_len); | |
1702 | return skb->data += len; | |
1703 | } | |
1704 | ||
47d29646 DM |
1705 | static inline unsigned char *skb_pull_inline(struct sk_buff *skb, unsigned int len) |
1706 | { | |
1707 | return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); | |
1708 | } | |
1709 | ||
7965bd4d | 1710 | unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); |
1da177e4 LT |
1711 | |
1712 | static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) | |
1713 | { | |
1714 | if (len > skb_headlen(skb) && | |
987c402a | 1715 | !__pskb_pull_tail(skb, len - skb_headlen(skb))) |
1da177e4 LT |
1716 | return NULL; |
1717 | skb->len -= len; | |
1718 | return skb->data += len; | |
1719 | } | |
1720 | ||
1721 | static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) | |
1722 | { | |
1723 | return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); | |
1724 | } | |
1725 | ||
1726 | static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) | |
1727 | { | |
1728 | if (likely(len <= skb_headlen(skb))) | |
1729 | return 1; | |
1730 | if (unlikely(len > skb->len)) | |
1731 | return 0; | |
987c402a | 1732 | return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL; |
1da177e4 LT |
1733 | } |
1734 | ||
1735 | /** | |
1736 | * skb_headroom - bytes at buffer head | |
1737 | * @skb: buffer to check | |
1738 | * | |
1739 | * Return the number of bytes of free space at the head of an &sk_buff. | |
1740 | */ | |
c2636b4d | 1741 | static inline unsigned int skb_headroom(const struct sk_buff *skb) |
1da177e4 LT |
1742 | { |
1743 | return skb->data - skb->head; | |
1744 | } | |
1745 | ||
1746 | /** | |
1747 | * skb_tailroom - bytes at buffer end | |
1748 | * @skb: buffer to check | |
1749 | * | |
1750 | * Return the number of bytes of free space at the tail of an sk_buff | |
1751 | */ | |
1752 | static inline int skb_tailroom(const struct sk_buff *skb) | |
1753 | { | |
4305b541 | 1754 | return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; |
1da177e4 LT |
1755 | } |
1756 | ||
a21d4572 ED |
1757 | /** |
1758 | * skb_availroom - bytes at buffer end | |
1759 | * @skb: buffer to check | |
1760 | * | |
1761 | * Return the number of bytes of free space at the tail of an sk_buff | |
1762 | * allocated by sk_stream_alloc() | |
1763 | */ | |
1764 | static inline int skb_availroom(const struct sk_buff *skb) | |
1765 | { | |
16fad69c ED |
1766 | if (skb_is_nonlinear(skb)) |
1767 | return 0; | |
1768 | ||
1769 | return skb->end - skb->tail - skb->reserved_tailroom; | |
a21d4572 ED |
1770 | } |
1771 | ||
1da177e4 LT |
1772 | /** |
1773 | * skb_reserve - adjust headroom | |
1774 | * @skb: buffer to alter | |
1775 | * @len: bytes to move | |
1776 | * | |
1777 | * Increase the headroom of an empty &sk_buff by reducing the tail | |
1778 | * room. This is only allowed for an empty buffer. | |
1779 | */ | |
8243126c | 1780 | static inline void skb_reserve(struct sk_buff *skb, int len) |
1da177e4 LT |
1781 | { |
1782 | skb->data += len; | |
1783 | skb->tail += len; | |
1784 | } | |
1785 | ||
8bce6d7d TH |
1786 | #define ENCAP_TYPE_ETHER 0 |
1787 | #define ENCAP_TYPE_IPPROTO 1 | |
1788 | ||
1789 | static inline void skb_set_inner_protocol(struct sk_buff *skb, | |
1790 | __be16 protocol) | |
1791 | { | |
1792 | skb->inner_protocol = protocol; | |
1793 | skb->inner_protocol_type = ENCAP_TYPE_ETHER; | |
1794 | } | |
1795 | ||
1796 | static inline void skb_set_inner_ipproto(struct sk_buff *skb, | |
1797 | __u8 ipproto) | |
1798 | { | |
1799 | skb->inner_ipproto = ipproto; | |
1800 | skb->inner_protocol_type = ENCAP_TYPE_IPPROTO; | |
1801 | } | |
1802 | ||
6a674e9c JG |
1803 | static inline void skb_reset_inner_headers(struct sk_buff *skb) |
1804 | { | |
aefbd2b3 | 1805 | skb->inner_mac_header = skb->mac_header; |
6a674e9c JG |
1806 | skb->inner_network_header = skb->network_header; |
1807 | skb->inner_transport_header = skb->transport_header; | |
1808 | } | |
1809 | ||
0b5c9db1 JP |
1810 | static inline void skb_reset_mac_len(struct sk_buff *skb) |
1811 | { | |
1812 | skb->mac_len = skb->network_header - skb->mac_header; | |
1813 | } | |
1814 | ||
6a674e9c JG |
1815 | static inline unsigned char *skb_inner_transport_header(const struct sk_buff |
1816 | *skb) | |
1817 | { | |
1818 | return skb->head + skb->inner_transport_header; | |
1819 | } | |
1820 | ||
1821 | static inline void skb_reset_inner_transport_header(struct sk_buff *skb) | |
1822 | { | |
1823 | skb->inner_transport_header = skb->data - skb->head; | |
1824 | } | |
1825 | ||
1826 | static inline void skb_set_inner_transport_header(struct sk_buff *skb, | |
1827 | const int offset) | |
1828 | { | |
1829 | skb_reset_inner_transport_header(skb); | |
1830 | skb->inner_transport_header += offset; | |
1831 | } | |
1832 | ||
1833 | static inline unsigned char *skb_inner_network_header(const struct sk_buff *skb) | |
1834 | { | |
1835 | return skb->head + skb->inner_network_header; | |
1836 | } | |
1837 | ||
1838 | static inline void skb_reset_inner_network_header(struct sk_buff *skb) | |
1839 | { | |
1840 | skb->inner_network_header = skb->data - skb->head; | |
1841 | } | |
1842 | ||
1843 | static inline void skb_set_inner_network_header(struct sk_buff *skb, | |
1844 | const int offset) | |
1845 | { | |
1846 | skb_reset_inner_network_header(skb); | |
1847 | skb->inner_network_header += offset; | |
1848 | } | |
1849 | ||
aefbd2b3 PS |
1850 | static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb) |
1851 | { | |
1852 | return skb->head + skb->inner_mac_header; | |
1853 | } | |
1854 | ||
1855 | static inline void skb_reset_inner_mac_header(struct sk_buff *skb) | |
1856 | { | |
1857 | skb->inner_mac_header = skb->data - skb->head; | |
1858 | } | |
1859 | ||
1860 | static inline void skb_set_inner_mac_header(struct sk_buff *skb, | |
1861 | const int offset) | |
1862 | { | |
1863 | skb_reset_inner_mac_header(skb); | |
1864 | skb->inner_mac_header += offset; | |
1865 | } | |
fda55eca ED |
1866 | static inline bool skb_transport_header_was_set(const struct sk_buff *skb) |
1867 | { | |
35d04610 | 1868 | return skb->transport_header != (typeof(skb->transport_header))~0U; |
fda55eca ED |
1869 | } |
1870 | ||
9c70220b ACM |
1871 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) |
1872 | { | |
2e07fa9c | 1873 | return skb->head + skb->transport_header; |
9c70220b ACM |
1874 | } |
1875 | ||
badff6d0 ACM |
1876 | static inline void skb_reset_transport_header(struct sk_buff *skb) |
1877 | { | |
2e07fa9c | 1878 | skb->transport_header = skb->data - skb->head; |
badff6d0 ACM |
1879 | } |
1880 | ||
967b05f6 ACM |
1881 | static inline void skb_set_transport_header(struct sk_buff *skb, |
1882 | const int offset) | |
1883 | { | |
2e07fa9c ACM |
1884 | skb_reset_transport_header(skb); |
1885 | skb->transport_header += offset; | |
ea2ae17d ACM |
1886 | } |
1887 | ||
d56f90a7 ACM |
1888 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) |
1889 | { | |
2e07fa9c | 1890 | return skb->head + skb->network_header; |
d56f90a7 ACM |
1891 | } |
1892 | ||
c1d2bbe1 ACM |
1893 | static inline void skb_reset_network_header(struct sk_buff *skb) |
1894 | { | |
2e07fa9c | 1895 | skb->network_header = skb->data - skb->head; |
c1d2bbe1 ACM |
1896 | } |
1897 | ||
c14d2450 ACM |
1898 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) |
1899 | { | |
2e07fa9c ACM |
1900 | skb_reset_network_header(skb); |
1901 | skb->network_header += offset; | |
c14d2450 ACM |
1902 | } |
1903 | ||
2e07fa9c | 1904 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) |
bbe735e4 | 1905 | { |
2e07fa9c | 1906 | return skb->head + skb->mac_header; |
bbe735e4 ACM |
1907 | } |
1908 | ||
2e07fa9c | 1909 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) |
cfe1fc77 | 1910 | { |
35d04610 | 1911 | return skb->mac_header != (typeof(skb->mac_header))~0U; |
2e07fa9c ACM |
1912 | } |
1913 | ||
1914 | static inline void skb_reset_mac_header(struct sk_buff *skb) | |
1915 | { | |
1916 | skb->mac_header = skb->data - skb->head; | |
1917 | } | |
1918 | ||
1919 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) | |
1920 | { | |
1921 | skb_reset_mac_header(skb); | |
1922 | skb->mac_header += offset; | |
1923 | } | |
1924 | ||
0e3da5bb TT |
1925 | static inline void skb_pop_mac_header(struct sk_buff *skb) |
1926 | { | |
1927 | skb->mac_header = skb->network_header; | |
1928 | } | |
1929 | ||
fbbdb8f0 YX |
1930 | static inline void skb_probe_transport_header(struct sk_buff *skb, |
1931 | const int offset_hint) | |
1932 | { | |
1933 | struct flow_keys keys; | |
1934 | ||
1935 | if (skb_transport_header_was_set(skb)) | |
1936 | return; | |
1937 | else if (skb_flow_dissect(skb, &keys)) | |
1938 | skb_set_transport_header(skb, keys.thoff); | |
1939 | else | |
1940 | skb_set_transport_header(skb, offset_hint); | |
1941 | } | |
1942 | ||
03606895 ED |
1943 | static inline void skb_mac_header_rebuild(struct sk_buff *skb) |
1944 | { | |
1945 | if (skb_mac_header_was_set(skb)) { | |
1946 | const unsigned char *old_mac = skb_mac_header(skb); | |
1947 | ||
1948 | skb_set_mac_header(skb, -skb->mac_len); | |
1949 | memmove(skb_mac_header(skb), old_mac, skb->mac_len); | |
1950 | } | |
1951 | } | |
1952 | ||
04fb451e MM |
1953 | static inline int skb_checksum_start_offset(const struct sk_buff *skb) |
1954 | { | |
1955 | return skb->csum_start - skb_headroom(skb); | |
1956 | } | |
1957 | ||
2e07fa9c ACM |
1958 | static inline int skb_transport_offset(const struct sk_buff *skb) |
1959 | { | |
1960 | return skb_transport_header(skb) - skb->data; | |
1961 | } | |
1962 | ||
1963 | static inline u32 skb_network_header_len(const struct sk_buff *skb) | |
1964 | { | |
1965 | return skb->transport_header - skb->network_header; | |
1966 | } | |
1967 | ||
6a674e9c JG |
1968 | static inline u32 skb_inner_network_header_len(const struct sk_buff *skb) |
1969 | { | |
1970 | return skb->inner_transport_header - skb->inner_network_header; | |
1971 | } | |
1972 | ||
2e07fa9c ACM |
1973 | static inline int skb_network_offset(const struct sk_buff *skb) |
1974 | { | |
1975 | return skb_network_header(skb) - skb->data; | |
1976 | } | |
48d49d0c | 1977 | |
6a674e9c JG |
1978 | static inline int skb_inner_network_offset(const struct sk_buff *skb) |
1979 | { | |
1980 | return skb_inner_network_header(skb) - skb->data; | |
1981 | } | |
1982 | ||
f9599ce1 CG |
1983 | static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len) |
1984 | { | |
1985 | return pskb_may_pull(skb, skb_network_offset(skb) + len); | |
1986 | } | |
1987 | ||
1da177e4 LT |
1988 | /* |
1989 | * CPUs often take a performance hit when accessing unaligned memory | |
1990 | * locations. The actual performance hit varies, it can be small if the | |
1991 | * hardware handles it or large if we have to take an exception and fix it | |
1992 | * in software. | |
1993 | * | |
1994 | * Since an ethernet header is 14 bytes network drivers often end up with | |
1995 | * the IP header at an unaligned offset. The IP header can be aligned by | |
1996 | * shifting the start of the packet by 2 bytes. Drivers should do this | |
1997 | * with: | |
1998 | * | |
8660c124 | 1999 | * skb_reserve(skb, NET_IP_ALIGN); |
1da177e4 LT |
2000 | * |
2001 | * The downside to this alignment of the IP header is that the DMA is now | |
2002 | * unaligned. On some architectures the cost of an unaligned DMA is high | |
2003 | * and this cost outweighs the gains made by aligning the IP header. | |
8660c124 | 2004 | * |
1da177e4 LT |
2005 | * Since this trade off varies between architectures, we allow NET_IP_ALIGN |
2006 | * to be overridden. | |
2007 | */ | |
2008 | #ifndef NET_IP_ALIGN | |
2009 | #define NET_IP_ALIGN 2 | |
2010 | #endif | |
2011 | ||
025be81e AB |
2012 | /* |
2013 | * The networking layer reserves some headroom in skb data (via | |
2014 | * dev_alloc_skb). This is used to avoid having to reallocate skb data when | |
2015 | * the header has to grow. In the default case, if the header has to grow | |
d6301d3d | 2016 | * 32 bytes or less we avoid the reallocation. |
025be81e AB |
2017 | * |
2018 | * Unfortunately this headroom changes the DMA alignment of the resulting | |
2019 | * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive | |
2020 | * on some architectures. An architecture can override this value, | |
2021 | * perhaps setting it to a cacheline in size (since that will maintain | |
2022 | * cacheline alignment of the DMA). It must be a power of 2. | |
2023 | * | |
d6301d3d | 2024 | * Various parts of the networking layer expect at least 32 bytes of |
025be81e | 2025 | * headroom, you should not reduce this. |
5933dd2f ED |
2026 | * |
2027 | * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS) | |
2028 | * to reduce average number of cache lines per packet. | |
2029 | * get_rps_cpus() for example only access one 64 bytes aligned block : | |
18e8c134 | 2030 | * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8) |
025be81e AB |
2031 | */ |
2032 | #ifndef NET_SKB_PAD | |
5933dd2f | 2033 | #define NET_SKB_PAD max(32, L1_CACHE_BYTES) |
025be81e AB |
2034 | #endif |
2035 | ||
7965bd4d | 2036 | int ___pskb_trim(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
2037 | |
2038 | static inline void __skb_trim(struct sk_buff *skb, unsigned int len) | |
2039 | { | |
c4264f27 | 2040 | if (unlikely(skb_is_nonlinear(skb))) { |
3cc0e873 HX |
2041 | WARN_ON(1); |
2042 | return; | |
2043 | } | |
27a884dc ACM |
2044 | skb->len = len; |
2045 | skb_set_tail_pointer(skb, len); | |
1da177e4 LT |
2046 | } |
2047 | ||
7965bd4d | 2048 | void skb_trim(struct sk_buff *skb, unsigned int len); |
1da177e4 LT |
2049 | |
2050 | static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) | |
2051 | { | |
3cc0e873 HX |
2052 | if (skb->data_len) |
2053 | return ___pskb_trim(skb, len); | |
2054 | __skb_trim(skb, len); | |
2055 | return 0; | |
1da177e4 LT |
2056 | } |
2057 | ||
2058 | static inline int pskb_trim(struct sk_buff *skb, unsigned int len) | |
2059 | { | |
2060 | return (len < skb->len) ? __pskb_trim(skb, len) : 0; | |
2061 | } | |
2062 | ||
e9fa4f7b HX |
2063 | /** |
2064 | * pskb_trim_unique - remove end from a paged unique (not cloned) buffer | |
2065 | * @skb: buffer to alter | |
2066 | * @len: new length | |
2067 | * | |
2068 | * This is identical to pskb_trim except that the caller knows that | |
2069 | * the skb is not cloned so we should never get an error due to out- | |
2070 | * of-memory. | |
2071 | */ | |
2072 | static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) | |
2073 | { | |
2074 | int err = pskb_trim(skb, len); | |
2075 | BUG_ON(err); | |
2076 | } | |
2077 | ||
1da177e4 LT |
2078 | /** |
2079 | * skb_orphan - orphan a buffer | |
2080 | * @skb: buffer to orphan | |
2081 | * | |
2082 | * If a buffer currently has an owner then we call the owner's | |
2083 | * destructor function and make the @skb unowned. The buffer continues | |
2084 | * to exist but is no longer charged to its former owner. | |
2085 | */ | |
2086 | static inline void skb_orphan(struct sk_buff *skb) | |
2087 | { | |
c34a7612 | 2088 | if (skb->destructor) { |
1da177e4 | 2089 | skb->destructor(skb); |
c34a7612 ED |
2090 | skb->destructor = NULL; |
2091 | skb->sk = NULL; | |
376c7311 ED |
2092 | } else { |
2093 | BUG_ON(skb->sk); | |
c34a7612 | 2094 | } |
1da177e4 LT |
2095 | } |
2096 | ||
a353e0ce MT |
2097 | /** |
2098 | * skb_orphan_frags - orphan the frags contained in a buffer | |
2099 | * @skb: buffer to orphan frags from | |
2100 | * @gfp_mask: allocation mask for replacement pages | |
2101 | * | |
2102 | * For each frag in the SKB which needs a destructor (i.e. has an | |
2103 | * owner) create a copy of that frag and release the original | |
2104 | * page by calling the destructor. | |
2105 | */ | |
2106 | static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask) | |
2107 | { | |
2108 | if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY))) | |
2109 | return 0; | |
2110 | return skb_copy_ubufs(skb, gfp_mask); | |
2111 | } | |
2112 | ||
1da177e4 LT |
2113 | /** |
2114 | * __skb_queue_purge - empty a list | |
2115 | * @list: list to empty | |
2116 | * | |
2117 | * Delete all buffers on an &sk_buff list. Each buffer is removed from | |
2118 | * the list and one reference dropped. This function does not take the | |
2119 | * list lock and the caller must hold the relevant locks to use it. | |
2120 | */ | |
7965bd4d | 2121 | void skb_queue_purge(struct sk_buff_head *list); |
1da177e4 LT |
2122 | static inline void __skb_queue_purge(struct sk_buff_head *list) |
2123 | { | |
2124 | struct sk_buff *skb; | |
2125 | while ((skb = __skb_dequeue(list)) != NULL) | |
2126 | kfree_skb(skb); | |
2127 | } | |
2128 | ||
e5e67305 AD |
2129 | #define NETDEV_FRAG_PAGE_MAX_ORDER get_order(32768) |
2130 | #define NETDEV_FRAG_PAGE_MAX_SIZE (PAGE_SIZE << NETDEV_FRAG_PAGE_MAX_ORDER) | |
2131 | #define NETDEV_PAGECNT_MAX_BIAS NETDEV_FRAG_PAGE_MAX_SIZE | |
2132 | ||
7965bd4d | 2133 | void *netdev_alloc_frag(unsigned int fragsz); |
1da177e4 | 2134 | |
7965bd4d JP |
2135 | struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length, |
2136 | gfp_t gfp_mask); | |
8af27456 CH |
2137 | |
2138 | /** | |
2139 | * netdev_alloc_skb - allocate an skbuff for rx on a specific device | |
2140 | * @dev: network device to receive on | |
2141 | * @length: length to allocate | |
2142 | * | |
2143 | * Allocate a new &sk_buff and assign it a usage count of one. The | |
2144 | * buffer has unspecified headroom built in. Users should allocate | |
2145 | * the headroom they think they need without accounting for the | |
2146 | * built in space. The built in space is used for optimisations. | |
2147 | * | |
2148 | * %NULL is returned if there is no free memory. Although this function | |
2149 | * allocates memory it can be called from an interrupt. | |
2150 | */ | |
2151 | static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, | |
6f532612 | 2152 | unsigned int length) |
8af27456 CH |
2153 | { |
2154 | return __netdev_alloc_skb(dev, length, GFP_ATOMIC); | |
2155 | } | |
2156 | ||
6f532612 ED |
2157 | /* legacy helper around __netdev_alloc_skb() */ |
2158 | static inline struct sk_buff *__dev_alloc_skb(unsigned int length, | |
2159 | gfp_t gfp_mask) | |
2160 | { | |
2161 | return __netdev_alloc_skb(NULL, length, gfp_mask); | |
2162 | } | |
2163 | ||
2164 | /* legacy helper around netdev_alloc_skb() */ | |
2165 | static inline struct sk_buff *dev_alloc_skb(unsigned int length) | |
2166 | { | |
2167 | return netdev_alloc_skb(NULL, length); | |
2168 | } | |
2169 | ||
2170 | ||
4915a0de ED |
2171 | static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, |
2172 | unsigned int length, gfp_t gfp) | |
61321bbd | 2173 | { |
4915a0de | 2174 | struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); |
61321bbd ED |
2175 | |
2176 | if (NET_IP_ALIGN && skb) | |
2177 | skb_reserve(skb, NET_IP_ALIGN); | |
2178 | return skb; | |
2179 | } | |
2180 | ||
4915a0de ED |
2181 | static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, |
2182 | unsigned int length) | |
2183 | { | |
2184 | return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC); | |
2185 | } | |
2186 | ||
71dfda58 AD |
2187 | /** |
2188 | * __dev_alloc_pages - allocate page for network Rx | |
2189 | * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx | |
2190 | * @order: size of the allocation | |
2191 | * | |
2192 | * Allocate a new page. | |
2193 | * | |
2194 | * %NULL is returned if there is no free memory. | |
2195 | */ | |
2196 | static inline struct page *__dev_alloc_pages(gfp_t gfp_mask, | |
2197 | unsigned int order) | |
2198 | { | |
2199 | /* This piece of code contains several assumptions. | |
2200 | * 1. This is for device Rx, therefor a cold page is preferred. | |
2201 | * 2. The expectation is the user wants a compound page. | |
2202 | * 3. If requesting a order 0 page it will not be compound | |
2203 | * due to the check to see if order has a value in prep_new_page | |
2204 | * 4. __GFP_MEMALLOC is ignored if __GFP_NOMEMALLOC is set due to | |
2205 | * code in gfp_to_alloc_flags that should be enforcing this. | |
2206 | */ | |
2207 | gfp_mask |= __GFP_COLD | __GFP_COMP | __GFP_MEMALLOC; | |
2208 | ||
2209 | return alloc_pages_node(NUMA_NO_NODE, gfp_mask, order); | |
2210 | } | |
2211 | ||
2212 | static inline struct page *dev_alloc_pages(unsigned int order) | |
2213 | { | |
2214 | return __dev_alloc_pages(GFP_ATOMIC, order); | |
2215 | } | |
2216 | ||
2217 | /** | |
2218 | * __dev_alloc_page - allocate a page for network Rx | |
2219 | * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx | |
2220 | * | |
2221 | * Allocate a new page. | |
2222 | * | |
2223 | * %NULL is returned if there is no free memory. | |
2224 | */ | |
2225 | static inline struct page *__dev_alloc_page(gfp_t gfp_mask) | |
2226 | { | |
2227 | return __dev_alloc_pages(gfp_mask, 0); | |
2228 | } | |
2229 | ||
2230 | static inline struct page *dev_alloc_page(void) | |
2231 | { | |
2232 | return __dev_alloc_page(GFP_ATOMIC); | |
2233 | } | |
2234 | ||
0614002b MG |
2235 | /** |
2236 | * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page | |
2237 | * @page: The page that was allocated from skb_alloc_page | |
2238 | * @skb: The skb that may need pfmemalloc set | |
2239 | */ | |
2240 | static inline void skb_propagate_pfmemalloc(struct page *page, | |
2241 | struct sk_buff *skb) | |
2242 | { | |
2243 | if (page && page->pfmemalloc) | |
2244 | skb->pfmemalloc = true; | |
2245 | } | |
2246 | ||
131ea667 | 2247 | /** |
e227867f | 2248 | * skb_frag_page - retrieve the page referred to by a paged fragment |
131ea667 IC |
2249 | * @frag: the paged fragment |
2250 | * | |
2251 | * Returns the &struct page associated with @frag. | |
2252 | */ | |
2253 | static inline struct page *skb_frag_page(const skb_frag_t *frag) | |
2254 | { | |
a8605c60 | 2255 | return frag->page.p; |
131ea667 IC |
2256 | } |
2257 | ||
2258 | /** | |
2259 | * __skb_frag_ref - take an addition reference on a paged fragment. | |
2260 | * @frag: the paged fragment | |
2261 | * | |
2262 | * Takes an additional reference on the paged fragment @frag. | |
2263 | */ | |
2264 | static inline void __skb_frag_ref(skb_frag_t *frag) | |
2265 | { | |
2266 | get_page(skb_frag_page(frag)); | |
2267 | } | |
2268 | ||
2269 | /** | |
2270 | * skb_frag_ref - take an addition reference on a paged fragment of an skb. | |
2271 | * @skb: the buffer | |
2272 | * @f: the fragment offset. | |
2273 | * | |
2274 | * Takes an additional reference on the @f'th paged fragment of @skb. | |
2275 | */ | |
2276 | static inline void skb_frag_ref(struct sk_buff *skb, int f) | |
2277 | { | |
2278 | __skb_frag_ref(&skb_shinfo(skb)->frags[f]); | |
2279 | } | |
2280 | ||
2281 | /** | |
2282 | * __skb_frag_unref - release a reference on a paged fragment. | |
2283 | * @frag: the paged fragment | |
2284 | * | |
2285 | * Releases a reference on the paged fragment @frag. | |
2286 | */ | |
2287 | static inline void __skb_frag_unref(skb_frag_t *frag) | |
2288 | { | |
2289 | put_page(skb_frag_page(frag)); | |
2290 | } | |
2291 | ||
2292 | /** | |
2293 | * skb_frag_unref - release a reference on a paged fragment of an skb. | |
2294 | * @skb: the buffer | |
2295 | * @f: the fragment offset | |
2296 | * | |
2297 | * Releases a reference on the @f'th paged fragment of @skb. | |
2298 | */ | |
2299 | static inline void skb_frag_unref(struct sk_buff *skb, int f) | |
2300 | { | |
2301 | __skb_frag_unref(&skb_shinfo(skb)->frags[f]); | |
2302 | } | |
2303 | ||
2304 | /** | |
2305 | * skb_frag_address - gets the address of the data contained in a paged fragment | |
2306 | * @frag: the paged fragment buffer | |
2307 | * | |
2308 | * Returns the address of the data within @frag. The page must already | |
2309 | * be mapped. | |
2310 | */ | |
2311 | static inline void *skb_frag_address(const skb_frag_t *frag) | |
2312 | { | |
2313 | return page_address(skb_frag_page(frag)) + frag->page_offset; | |
2314 | } | |
2315 | ||
2316 | /** | |
2317 | * skb_frag_address_safe - gets the address of the data contained in a paged fragment | |
2318 | * @frag: the paged fragment buffer | |
2319 | * | |
2320 | * Returns the address of the data within @frag. Checks that the page | |
2321 | * is mapped and returns %NULL otherwise. | |
2322 | */ | |
2323 | static inline void *skb_frag_address_safe(const skb_frag_t *frag) | |
2324 | { | |
2325 | void *ptr = page_address(skb_frag_page(frag)); | |
2326 | if (unlikely(!ptr)) | |
2327 | return NULL; | |
2328 | ||
2329 | return ptr + frag->page_offset; | |
2330 | } | |
2331 | ||
2332 | /** | |
2333 | * __skb_frag_set_page - sets the page contained in a paged fragment | |
2334 | * @frag: the paged fragment | |
2335 | * @page: the page to set | |
2336 | * | |
2337 | * Sets the fragment @frag to contain @page. | |
2338 | */ | |
2339 | static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page) | |
2340 | { | |
a8605c60 | 2341 | frag->page.p = page; |
131ea667 IC |
2342 | } |
2343 | ||
2344 | /** | |
2345 | * skb_frag_set_page - sets the page contained in a paged fragment of an skb | |
2346 | * @skb: the buffer | |
2347 | * @f: the fragment offset | |
2348 | * @page: the page to set | |
2349 | * | |
2350 | * Sets the @f'th fragment of @skb to contain @page. | |
2351 | */ | |
2352 | static inline void skb_frag_set_page(struct sk_buff *skb, int f, | |
2353 | struct page *page) | |
2354 | { | |
2355 | __skb_frag_set_page(&skb_shinfo(skb)->frags[f], page); | |
2356 | } | |
2357 | ||
400dfd3a ED |
2358 | bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio); |
2359 | ||
131ea667 IC |
2360 | /** |
2361 | * skb_frag_dma_map - maps a paged fragment via the DMA API | |
f83347df | 2362 | * @dev: the device to map the fragment to |
131ea667 IC |
2363 | * @frag: the paged fragment to map |
2364 | * @offset: the offset within the fragment (starting at the | |
2365 | * fragment's own offset) | |
2366 | * @size: the number of bytes to map | |
f83347df | 2367 | * @dir: the direction of the mapping (%PCI_DMA_*) |
131ea667 IC |
2368 | * |
2369 | * Maps the page associated with @frag to @device. | |
2370 | */ | |
2371 | static inline dma_addr_t skb_frag_dma_map(struct device *dev, | |
2372 | const skb_frag_t *frag, | |
2373 | size_t offset, size_t size, | |
2374 | enum dma_data_direction dir) | |
2375 | { | |
2376 | return dma_map_page(dev, skb_frag_page(frag), | |
2377 | frag->page_offset + offset, size, dir); | |
2378 | } | |
2379 | ||
117632e6 ED |
2380 | static inline struct sk_buff *pskb_copy(struct sk_buff *skb, |
2381 | gfp_t gfp_mask) | |
2382 | { | |
2383 | return __pskb_copy(skb, skb_headroom(skb), gfp_mask); | |
2384 | } | |
2385 | ||
bad93e9d OP |
2386 | |
2387 | static inline struct sk_buff *pskb_copy_for_clone(struct sk_buff *skb, | |
2388 | gfp_t gfp_mask) | |
2389 | { | |
2390 | return __pskb_copy_fclone(skb, skb_headroom(skb), gfp_mask, true); | |
2391 | } | |
2392 | ||
2393 | ||
334a8132 PM |
2394 | /** |
2395 | * skb_clone_writable - is the header of a clone writable | |
2396 | * @skb: buffer to check | |
2397 | * @len: length up to which to write | |
2398 | * | |
2399 | * Returns true if modifying the header part of the cloned buffer | |
2400 | * does not requires the data to be copied. | |
2401 | */ | |
05bdd2f1 | 2402 | static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len) |
334a8132 PM |
2403 | { |
2404 | return !skb_header_cloned(skb) && | |
2405 | skb_headroom(skb) + len <= skb->hdr_len; | |
2406 | } | |
2407 | ||
d9cc2048 HX |
2408 | static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom, |
2409 | int cloned) | |
2410 | { | |
2411 | int delta = 0; | |
2412 | ||
d9cc2048 HX |
2413 | if (headroom > skb_headroom(skb)) |
2414 | delta = headroom - skb_headroom(skb); | |
2415 | ||
2416 | if (delta || cloned) | |
2417 | return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, | |
2418 | GFP_ATOMIC); | |
2419 | return 0; | |
2420 | } | |
2421 | ||
1da177e4 LT |
2422 | /** |
2423 | * skb_cow - copy header of skb when it is required | |
2424 | * @skb: buffer to cow | |
2425 | * @headroom: needed headroom | |
2426 | * | |
2427 | * If the skb passed lacks sufficient headroom or its data part | |
2428 | * is shared, data is reallocated. If reallocation fails, an error | |
2429 | * is returned and original skb is not changed. | |
2430 | * | |
2431 | * The result is skb with writable area skb->head...skb->tail | |
2432 | * and at least @headroom of space at head. | |
2433 | */ | |
2434 | static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) | |
2435 | { | |
d9cc2048 HX |
2436 | return __skb_cow(skb, headroom, skb_cloned(skb)); |
2437 | } | |
1da177e4 | 2438 | |
d9cc2048 HX |
2439 | /** |
2440 | * skb_cow_head - skb_cow but only making the head writable | |
2441 | * @skb: buffer to cow | |
2442 | * @headroom: needed headroom | |
2443 | * | |
2444 | * This function is identical to skb_cow except that we replace the | |
2445 | * skb_cloned check by skb_header_cloned. It should be used when | |
2446 | * you only need to push on some header and do not need to modify | |
2447 | * the data. | |
2448 | */ | |
2449 | static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom) | |
2450 | { | |
2451 | return __skb_cow(skb, headroom, skb_header_cloned(skb)); | |
1da177e4 LT |
2452 | } |
2453 | ||
2454 | /** | |
2455 | * skb_padto - pad an skbuff up to a minimal size | |
2456 | * @skb: buffer to pad | |
2457 | * @len: minimal length | |
2458 | * | |
2459 | * Pads up a buffer to ensure the trailing bytes exist and are | |
2460 | * blanked. If the buffer already contains sufficient data it | |
5b057c6b HX |
2461 | * is untouched. Otherwise it is extended. Returns zero on |
2462 | * success. The skb is freed on error. | |
1da177e4 LT |
2463 | */ |
2464 | ||
5b057c6b | 2465 | static inline int skb_padto(struct sk_buff *skb, unsigned int len) |
1da177e4 LT |
2466 | { |
2467 | unsigned int size = skb->len; | |
2468 | if (likely(size >= len)) | |
5b057c6b | 2469 | return 0; |
987c402a | 2470 | return skb_pad(skb, len - size); |
1da177e4 LT |
2471 | } |
2472 | ||
2473 | static inline int skb_add_data(struct sk_buff *skb, | |
2474 | char __user *from, int copy) | |
2475 | { | |
2476 | const int off = skb->len; | |
2477 | ||
2478 | if (skb->ip_summed == CHECKSUM_NONE) { | |
2479 | int err = 0; | |
5084205f | 2480 | __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), |
1da177e4 LT |
2481 | copy, 0, &err); |
2482 | if (!err) { | |
2483 | skb->csum = csum_block_add(skb->csum, csum, off); | |
2484 | return 0; | |
2485 | } | |
2486 | } else if (!copy_from_user(skb_put(skb, copy), from, copy)) | |
2487 | return 0; | |
2488 | ||
2489 | __skb_trim(skb, off); | |
2490 | return -EFAULT; | |
2491 | } | |
2492 | ||
38ba0a65 ED |
2493 | static inline bool skb_can_coalesce(struct sk_buff *skb, int i, |
2494 | const struct page *page, int off) | |
1da177e4 LT |
2495 | { |
2496 | if (i) { | |
9e903e08 | 2497 | const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; |
1da177e4 | 2498 | |
ea2ab693 | 2499 | return page == skb_frag_page(frag) && |
9e903e08 | 2500 | off == frag->page_offset + skb_frag_size(frag); |
1da177e4 | 2501 | } |
38ba0a65 | 2502 | return false; |
1da177e4 LT |
2503 | } |
2504 | ||
364c6bad HX |
2505 | static inline int __skb_linearize(struct sk_buff *skb) |
2506 | { | |
2507 | return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; | |
2508 | } | |
2509 | ||
1da177e4 LT |
2510 | /** |
2511 | * skb_linearize - convert paged skb to linear one | |
2512 | * @skb: buffer to linarize | |
1da177e4 LT |
2513 | * |
2514 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
2515 | * is returned and the old skb data released. | |
2516 | */ | |
364c6bad HX |
2517 | static inline int skb_linearize(struct sk_buff *skb) |
2518 | { | |
2519 | return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; | |
2520 | } | |
2521 | ||
cef401de ED |
2522 | /** |
2523 | * skb_has_shared_frag - can any frag be overwritten | |
2524 | * @skb: buffer to test | |
2525 | * | |
2526 | * Return true if the skb has at least one frag that might be modified | |
2527 | * by an external entity (as in vmsplice()/sendfile()) | |
2528 | */ | |
2529 | static inline bool skb_has_shared_frag(const struct sk_buff *skb) | |
2530 | { | |
c9af6db4 PS |
2531 | return skb_is_nonlinear(skb) && |
2532 | skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; | |
cef401de ED |
2533 | } |
2534 | ||
364c6bad HX |
2535 | /** |
2536 | * skb_linearize_cow - make sure skb is linear and writable | |
2537 | * @skb: buffer to process | |
2538 | * | |
2539 | * If there is no free memory -ENOMEM is returned, otherwise zero | |
2540 | * is returned and the old skb data released. | |
2541 | */ | |
2542 | static inline int skb_linearize_cow(struct sk_buff *skb) | |
1da177e4 | 2543 | { |
364c6bad HX |
2544 | return skb_is_nonlinear(skb) || skb_cloned(skb) ? |
2545 | __skb_linearize(skb) : 0; | |
1da177e4 LT |
2546 | } |
2547 | ||
2548 | /** | |
2549 | * skb_postpull_rcsum - update checksum for received skb after pull | |
2550 | * @skb: buffer to update | |
2551 | * @start: start of data before pull | |
2552 | * @len: length of data pulled | |
2553 | * | |
2554 | * After doing a pull on a received packet, you need to call this to | |
84fa7933 PM |
2555 | * update the CHECKSUM_COMPLETE checksum, or set ip_summed to |
2556 | * CHECKSUM_NONE so that it can be recomputed from scratch. | |
1da177e4 LT |
2557 | */ |
2558 | ||
2559 | static inline void skb_postpull_rcsum(struct sk_buff *skb, | |
cbb042f9 | 2560 | const void *start, unsigned int len) |
1da177e4 | 2561 | { |
84fa7933 | 2562 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
1da177e4 LT |
2563 | skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); |
2564 | } | |
2565 | ||
cbb042f9 HX |
2566 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); |
2567 | ||
7ce5a27f DM |
2568 | /** |
2569 | * pskb_trim_rcsum - trim received skb and update checksum | |
2570 | * @skb: buffer to trim | |
2571 | * @len: new length | |
2572 | * | |
2573 | * This is exactly the same as pskb_trim except that it ensures the | |
2574 | * checksum of received packets are still valid after the operation. | |
2575 | */ | |
2576 | ||
2577 | static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) | |
2578 | { | |
2579 | if (likely(len >= skb->len)) | |
2580 | return 0; | |
2581 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
2582 | skb->ip_summed = CHECKSUM_NONE; | |
2583 | return __pskb_trim(skb, len); | |
2584 | } | |
2585 | ||
1da177e4 LT |
2586 | #define skb_queue_walk(queue, skb) \ |
2587 | for (skb = (queue)->next; \ | |
a1e4891f | 2588 | skb != (struct sk_buff *)(queue); \ |
1da177e4 LT |
2589 | skb = skb->next) |
2590 | ||
46f8914e JC |
2591 | #define skb_queue_walk_safe(queue, skb, tmp) \ |
2592 | for (skb = (queue)->next, tmp = skb->next; \ | |
2593 | skb != (struct sk_buff *)(queue); \ | |
2594 | skb = tmp, tmp = skb->next) | |
2595 | ||
1164f52a | 2596 | #define skb_queue_walk_from(queue, skb) \ |
a1e4891f | 2597 | for (; skb != (struct sk_buff *)(queue); \ |
1164f52a DM |
2598 | skb = skb->next) |
2599 | ||
2600 | #define skb_queue_walk_from_safe(queue, skb, tmp) \ | |
2601 | for (tmp = skb->next; \ | |
2602 | skb != (struct sk_buff *)(queue); \ | |
2603 | skb = tmp, tmp = skb->next) | |
2604 | ||
300ce174 SH |
2605 | #define skb_queue_reverse_walk(queue, skb) \ |
2606 | for (skb = (queue)->prev; \ | |
a1e4891f | 2607 | skb != (struct sk_buff *)(queue); \ |
300ce174 SH |
2608 | skb = skb->prev) |
2609 | ||
686a2955 DM |
2610 | #define skb_queue_reverse_walk_safe(queue, skb, tmp) \ |
2611 | for (skb = (queue)->prev, tmp = skb->prev; \ | |
2612 | skb != (struct sk_buff *)(queue); \ | |
2613 | skb = tmp, tmp = skb->prev) | |
2614 | ||
2615 | #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \ | |
2616 | for (tmp = skb->prev; \ | |
2617 | skb != (struct sk_buff *)(queue); \ | |
2618 | skb = tmp, tmp = skb->prev) | |
1da177e4 | 2619 | |
21dc3301 | 2620 | static inline bool skb_has_frag_list(const struct sk_buff *skb) |
ee039871 DM |
2621 | { |
2622 | return skb_shinfo(skb)->frag_list != NULL; | |
2623 | } | |
2624 | ||
2625 | static inline void skb_frag_list_init(struct sk_buff *skb) | |
2626 | { | |
2627 | skb_shinfo(skb)->frag_list = NULL; | |
2628 | } | |
2629 | ||
2630 | static inline void skb_frag_add_head(struct sk_buff *skb, struct sk_buff *frag) | |
2631 | { | |
2632 | frag->next = skb_shinfo(skb)->frag_list; | |
2633 | skb_shinfo(skb)->frag_list = frag; | |
2634 | } | |
2635 | ||
2636 | #define skb_walk_frags(skb, iter) \ | |
2637 | for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next) | |
2638 | ||
7965bd4d JP |
2639 | struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, |
2640 | int *peeked, int *off, int *err); | |
2641 | struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock, | |
2642 | int *err); | |
2643 | unsigned int datagram_poll(struct file *file, struct socket *sock, | |
2644 | struct poll_table_struct *wait); | |
2645 | int skb_copy_datagram_iovec(const struct sk_buff *from, int offset, | |
2646 | struct iovec *to, int size); | |
51f3d02b DM |
2647 | static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset, |
2648 | struct msghdr *msg, int size) | |
2649 | { | |
2650 | return skb_copy_datagram_iovec(from, offset, msg->msg_iov, size); | |
2651 | } | |
7965bd4d JP |
2652 | int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, int hlen, |
2653 | struct iovec *iov); | |
2654 | int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, | |
2655 | const struct iovec *from, int from_offset, | |
2656 | int len); | |
2657 | int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *frm, | |
2658 | int offset, size_t count); | |
a8f820aa HX |
2659 | int skb_copy_datagram_iter(const struct sk_buff *from, int offset, |
2660 | struct iov_iter *to, int size); | |
7965bd4d JP |
2661 | void skb_free_datagram(struct sock *sk, struct sk_buff *skb); |
2662 | void skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb); | |
2663 | int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags); | |
7965bd4d JP |
2664 | int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len); |
2665 | int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len); | |
2666 | __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, | |
2667 | int len, __wsum csum); | |
2668 | int skb_splice_bits(struct sk_buff *skb, unsigned int offset, | |
2669 | struct pipe_inode_info *pipe, unsigned int len, | |
2670 | unsigned int flags); | |
2671 | void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); | |
af2806f8 | 2672 | unsigned int skb_zerocopy_headlen(const struct sk_buff *from); |
36d5fe6a ZK |
2673 | int skb_zerocopy(struct sk_buff *to, struct sk_buff *from, |
2674 | int len, int hlen); | |
7965bd4d JP |
2675 | void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); |
2676 | int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen); | |
2677 | void skb_scrub_packet(struct sk_buff *skb, bool xnet); | |
de960aa9 | 2678 | unsigned int skb_gso_transport_seglen(const struct sk_buff *skb); |
7965bd4d | 2679 | struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features); |
0d5501c1 | 2680 | struct sk_buff *skb_vlan_untag(struct sk_buff *skb); |
e2195121 | 2681 | int skb_ensure_writable(struct sk_buff *skb, int write_len); |
93515d53 JP |
2682 | int skb_vlan_pop(struct sk_buff *skb); |
2683 | int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci); | |
20380731 | 2684 | |
2817a336 DB |
2685 | struct skb_checksum_ops { |
2686 | __wsum (*update)(const void *mem, int len, __wsum wsum); | |
2687 | __wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len); | |
2688 | }; | |
2689 | ||
2690 | __wsum __skb_checksum(const struct sk_buff *skb, int offset, int len, | |
2691 | __wsum csum, const struct skb_checksum_ops *ops); | |
2692 | __wsum skb_checksum(const struct sk_buff *skb, int offset, int len, | |
2693 | __wsum csum); | |
2694 | ||
690e36e7 DM |
2695 | static inline void *__skb_header_pointer(const struct sk_buff *skb, int offset, |
2696 | int len, void *data, int hlen, void *buffer) | |
1da177e4 | 2697 | { |
55820ee2 | 2698 | if (hlen - offset >= len) |
690e36e7 | 2699 | return data + offset; |
1da177e4 | 2700 | |
690e36e7 DM |
2701 | if (!skb || |
2702 | skb_copy_bits(skb, offset, buffer, len) < 0) | |
1da177e4 LT |
2703 | return NULL; |
2704 | ||
2705 | return buffer; | |
2706 | } | |
2707 | ||
690e36e7 DM |
2708 | static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, |
2709 | int len, void *buffer) | |
2710 | { | |
2711 | return __skb_header_pointer(skb, offset, len, skb->data, | |
2712 | skb_headlen(skb), buffer); | |
2713 | } | |
2714 | ||
4262e5cc DB |
2715 | /** |
2716 | * skb_needs_linearize - check if we need to linearize a given skb | |
2717 | * depending on the given device features. | |
2718 | * @skb: socket buffer to check | |
2719 | * @features: net device features | |
2720 | * | |
2721 | * Returns true if either: | |
2722 | * 1. skb has frag_list and the device doesn't support FRAGLIST, or | |
2723 | * 2. skb is fragmented and the device does not support SG. | |
2724 | */ | |
2725 | static inline bool skb_needs_linearize(struct sk_buff *skb, | |
2726 | netdev_features_t features) | |
2727 | { | |
2728 | return skb_is_nonlinear(skb) && | |
2729 | ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) || | |
2730 | (skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG))); | |
2731 | } | |
2732 | ||
d626f62b ACM |
2733 | static inline void skb_copy_from_linear_data(const struct sk_buff *skb, |
2734 | void *to, | |
2735 | const unsigned int len) | |
2736 | { | |
2737 | memcpy(to, skb->data, len); | |
2738 | } | |
2739 | ||
2740 | static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, | |
2741 | const int offset, void *to, | |
2742 | const unsigned int len) | |
2743 | { | |
2744 | memcpy(to, skb->data + offset, len); | |
2745 | } | |
2746 | ||
27d7ff46 ACM |
2747 | static inline void skb_copy_to_linear_data(struct sk_buff *skb, |
2748 | const void *from, | |
2749 | const unsigned int len) | |
2750 | { | |
2751 | memcpy(skb->data, from, len); | |
2752 | } | |
2753 | ||
2754 | static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, | |
2755 | const int offset, | |
2756 | const void *from, | |
2757 | const unsigned int len) | |
2758 | { | |
2759 | memcpy(skb->data + offset, from, len); | |
2760 | } | |
2761 | ||
7965bd4d | 2762 | void skb_init(void); |
1da177e4 | 2763 | |
ac45f602 PO |
2764 | static inline ktime_t skb_get_ktime(const struct sk_buff *skb) |
2765 | { | |
2766 | return skb->tstamp; | |
2767 | } | |
2768 | ||
a61bbcf2 PM |
2769 | /** |
2770 | * skb_get_timestamp - get timestamp from a skb | |
2771 | * @skb: skb to get stamp from | |
2772 | * @stamp: pointer to struct timeval to store stamp in | |
2773 | * | |
2774 | * Timestamps are stored in the skb as offsets to a base timestamp. | |
2775 | * This function converts the offset back to a struct timeval and stores | |
2776 | * it in stamp. | |
2777 | */ | |
ac45f602 PO |
2778 | static inline void skb_get_timestamp(const struct sk_buff *skb, |
2779 | struct timeval *stamp) | |
a61bbcf2 | 2780 | { |
b7aa0bf7 | 2781 | *stamp = ktime_to_timeval(skb->tstamp); |
a61bbcf2 PM |
2782 | } |
2783 | ||
ac45f602 PO |
2784 | static inline void skb_get_timestampns(const struct sk_buff *skb, |
2785 | struct timespec *stamp) | |
2786 | { | |
2787 | *stamp = ktime_to_timespec(skb->tstamp); | |
2788 | } | |
2789 | ||
b7aa0bf7 | 2790 | static inline void __net_timestamp(struct sk_buff *skb) |
a61bbcf2 | 2791 | { |
b7aa0bf7 | 2792 | skb->tstamp = ktime_get_real(); |
a61bbcf2 PM |
2793 | } |
2794 | ||
164891aa SH |
2795 | static inline ktime_t net_timedelta(ktime_t t) |
2796 | { | |
2797 | return ktime_sub(ktime_get_real(), t); | |
2798 | } | |
2799 | ||
b9ce204f IJ |
2800 | static inline ktime_t net_invalid_timestamp(void) |
2801 | { | |
2802 | return ktime_set(0, 0); | |
2803 | } | |
a61bbcf2 | 2804 | |
62bccb8c AD |
2805 | struct sk_buff *skb_clone_sk(struct sk_buff *skb); |
2806 | ||
c1f19b51 RC |
2807 | #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING |
2808 | ||
7965bd4d JP |
2809 | void skb_clone_tx_timestamp(struct sk_buff *skb); |
2810 | bool skb_defer_rx_timestamp(struct sk_buff *skb); | |
c1f19b51 RC |
2811 | |
2812 | #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */ | |
2813 | ||
2814 | static inline void skb_clone_tx_timestamp(struct sk_buff *skb) | |
2815 | { | |
2816 | } | |
2817 | ||
2818 | static inline bool skb_defer_rx_timestamp(struct sk_buff *skb) | |
2819 | { | |
2820 | return false; | |
2821 | } | |
2822 | ||
2823 | #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */ | |
2824 | ||
2825 | /** | |
2826 | * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps | |
2827 | * | |
da92b194 RC |
2828 | * PHY drivers may accept clones of transmitted packets for |
2829 | * timestamping via their phy_driver.txtstamp method. These drivers | |
2830 | * must call this function to return the skb back to the stack, with | |
2831 | * or without a timestamp. | |
2832 | * | |
c1f19b51 | 2833 | * @skb: clone of the the original outgoing packet |
da92b194 | 2834 | * @hwtstamps: hardware time stamps, may be NULL if not available |
c1f19b51 RC |
2835 | * |
2836 | */ | |
2837 | void skb_complete_tx_timestamp(struct sk_buff *skb, | |
2838 | struct skb_shared_hwtstamps *hwtstamps); | |
2839 | ||
e7fd2885 WB |
2840 | void __skb_tstamp_tx(struct sk_buff *orig_skb, |
2841 | struct skb_shared_hwtstamps *hwtstamps, | |
2842 | struct sock *sk, int tstype); | |
2843 | ||
ac45f602 PO |
2844 | /** |
2845 | * skb_tstamp_tx - queue clone of skb with send time stamps | |
2846 | * @orig_skb: the original outgoing packet | |
2847 | * @hwtstamps: hardware time stamps, may be NULL if not available | |
2848 | * | |
2849 | * If the skb has a socket associated, then this function clones the | |
2850 | * skb (thus sharing the actual data and optional structures), stores | |
2851 | * the optional hardware time stamping information (if non NULL) or | |
2852 | * generates a software time stamp (otherwise), then queues the clone | |
2853 | * to the error queue of the socket. Errors are silently ignored. | |
2854 | */ | |
7965bd4d JP |
2855 | void skb_tstamp_tx(struct sk_buff *orig_skb, |
2856 | struct skb_shared_hwtstamps *hwtstamps); | |
ac45f602 | 2857 | |
4507a715 RC |
2858 | static inline void sw_tx_timestamp(struct sk_buff *skb) |
2859 | { | |
2244d07b OH |
2860 | if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP && |
2861 | !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) | |
4507a715 RC |
2862 | skb_tstamp_tx(skb, NULL); |
2863 | } | |
2864 | ||
2865 | /** | |
2866 | * skb_tx_timestamp() - Driver hook for transmit timestamping | |
2867 | * | |
2868 | * Ethernet MAC Drivers should call this function in their hard_xmit() | |
4ff75b7c | 2869 | * function immediately before giving the sk_buff to the MAC hardware. |
4507a715 | 2870 | * |
73409f3b DM |
2871 | * Specifically, one should make absolutely sure that this function is |
2872 | * called before TX completion of this packet can trigger. Otherwise | |
2873 | * the packet could potentially already be freed. | |
2874 | * | |
4507a715 RC |
2875 | * @skb: A socket buffer. |
2876 | */ | |
2877 | static inline void skb_tx_timestamp(struct sk_buff *skb) | |
2878 | { | |
c1f19b51 | 2879 | skb_clone_tx_timestamp(skb); |
4507a715 RC |
2880 | sw_tx_timestamp(skb); |
2881 | } | |
2882 | ||
6e3e939f JB |
2883 | /** |
2884 | * skb_complete_wifi_ack - deliver skb with wifi status | |
2885 | * | |
2886 | * @skb: the original outgoing packet | |
2887 | * @acked: ack status | |
2888 | * | |
2889 | */ | |
2890 | void skb_complete_wifi_ack(struct sk_buff *skb, bool acked); | |
2891 | ||
7965bd4d JP |
2892 | __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); |
2893 | __sum16 __skb_checksum_complete(struct sk_buff *skb); | |
fb286bb2 | 2894 | |
60476372 HX |
2895 | static inline int skb_csum_unnecessary(const struct sk_buff *skb) |
2896 | { | |
5d0c2b95 | 2897 | return ((skb->ip_summed & CHECKSUM_UNNECESSARY) || skb->csum_valid); |
60476372 HX |
2898 | } |
2899 | ||
fb286bb2 HX |
2900 | /** |
2901 | * skb_checksum_complete - Calculate checksum of an entire packet | |
2902 | * @skb: packet to process | |
2903 | * | |
2904 | * This function calculates the checksum over the entire packet plus | |
2905 | * the value of skb->csum. The latter can be used to supply the | |
2906 | * checksum of a pseudo header as used by TCP/UDP. It returns the | |
2907 | * checksum. | |
2908 | * | |
2909 | * For protocols that contain complete checksums such as ICMP/TCP/UDP, | |
2910 | * this function can be used to verify that checksum on received | |
2911 | * packets. In that case the function should return zero if the | |
2912 | * checksum is correct. In particular, this function will return zero | |
2913 | * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the | |
2914 | * hardware has already verified the correctness of the checksum. | |
2915 | */ | |
4381ca3c | 2916 | static inline __sum16 skb_checksum_complete(struct sk_buff *skb) |
fb286bb2 | 2917 | { |
60476372 HX |
2918 | return skb_csum_unnecessary(skb) ? |
2919 | 0 : __skb_checksum_complete(skb); | |
fb286bb2 HX |
2920 | } |
2921 | ||
77cffe23 TH |
2922 | static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb) |
2923 | { | |
2924 | if (skb->ip_summed == CHECKSUM_UNNECESSARY) { | |
2925 | if (skb->csum_level == 0) | |
2926 | skb->ip_summed = CHECKSUM_NONE; | |
2927 | else | |
2928 | skb->csum_level--; | |
2929 | } | |
2930 | } | |
2931 | ||
2932 | static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb) | |
2933 | { | |
2934 | if (skb->ip_summed == CHECKSUM_UNNECESSARY) { | |
2935 | if (skb->csum_level < SKB_MAX_CSUM_LEVEL) | |
2936 | skb->csum_level++; | |
2937 | } else if (skb->ip_summed == CHECKSUM_NONE) { | |
2938 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
2939 | skb->csum_level = 0; | |
2940 | } | |
2941 | } | |
2942 | ||
5a212329 TH |
2943 | static inline void __skb_mark_checksum_bad(struct sk_buff *skb) |
2944 | { | |
2945 | /* Mark current checksum as bad (typically called from GRO | |
2946 | * path). In the case that ip_summed is CHECKSUM_NONE | |
2947 | * this must be the first checksum encountered in the packet. | |
2948 | * When ip_summed is CHECKSUM_UNNECESSARY, this is the first | |
2949 | * checksum after the last one validated. For UDP, a zero | |
2950 | * checksum can not be marked as bad. | |
2951 | */ | |
2952 | ||
2953 | if (skb->ip_summed == CHECKSUM_NONE || | |
2954 | skb->ip_summed == CHECKSUM_UNNECESSARY) | |
2955 | skb->csum_bad = 1; | |
2956 | } | |
2957 | ||
76ba0aae TH |
2958 | /* Check if we need to perform checksum complete validation. |
2959 | * | |
2960 | * Returns true if checksum complete is needed, false otherwise | |
2961 | * (either checksum is unnecessary or zero checksum is allowed). | |
2962 | */ | |
2963 | static inline bool __skb_checksum_validate_needed(struct sk_buff *skb, | |
2964 | bool zero_okay, | |
2965 | __sum16 check) | |
2966 | { | |
5d0c2b95 TH |
2967 | if (skb_csum_unnecessary(skb) || (zero_okay && !check)) { |
2968 | skb->csum_valid = 1; | |
77cffe23 | 2969 | __skb_decr_checksum_unnecessary(skb); |
76ba0aae TH |
2970 | return false; |
2971 | } | |
2972 | ||
2973 | return true; | |
2974 | } | |
2975 | ||
2976 | /* For small packets <= CHECKSUM_BREAK peform checksum complete directly | |
2977 | * in checksum_init. | |
2978 | */ | |
2979 | #define CHECKSUM_BREAK 76 | |
2980 | ||
2981 | /* Validate (init) checksum based on checksum complete. | |
2982 | * | |
2983 | * Return values: | |
2984 | * 0: checksum is validated or try to in skb_checksum_complete. In the latter | |
2985 | * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo | |
2986 | * checksum is stored in skb->csum for use in __skb_checksum_complete | |
2987 | * non-zero: value of invalid checksum | |
2988 | * | |
2989 | */ | |
2990 | static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb, | |
2991 | bool complete, | |
2992 | __wsum psum) | |
2993 | { | |
2994 | if (skb->ip_summed == CHECKSUM_COMPLETE) { | |
2995 | if (!csum_fold(csum_add(psum, skb->csum))) { | |
5d0c2b95 | 2996 | skb->csum_valid = 1; |
76ba0aae TH |
2997 | return 0; |
2998 | } | |
5a212329 TH |
2999 | } else if (skb->csum_bad) { |
3000 | /* ip_summed == CHECKSUM_NONE in this case */ | |
3001 | return 1; | |
76ba0aae TH |
3002 | } |
3003 | ||
3004 | skb->csum = psum; | |
3005 | ||
5d0c2b95 TH |
3006 | if (complete || skb->len <= CHECKSUM_BREAK) { |
3007 | __sum16 csum; | |
3008 | ||
3009 | csum = __skb_checksum_complete(skb); | |
3010 | skb->csum_valid = !csum; | |
3011 | return csum; | |
3012 | } | |
76ba0aae TH |
3013 | |
3014 | return 0; | |
3015 | } | |
3016 | ||
3017 | static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto) | |
3018 | { | |
3019 | return 0; | |
3020 | } | |
3021 | ||
3022 | /* Perform checksum validate (init). Note that this is a macro since we only | |
3023 | * want to calculate the pseudo header which is an input function if necessary. | |
3024 | * First we try to validate without any computation (checksum unnecessary) and | |
3025 | * then calculate based on checksum complete calling the function to compute | |
3026 | * pseudo header. | |
3027 | * | |
3028 | * Return values: | |
3029 | * 0: checksum is validated or try to in skb_checksum_complete | |
3030 | * non-zero: value of invalid checksum | |
3031 | */ | |
3032 | #define __skb_checksum_validate(skb, proto, complete, \ | |
3033 | zero_okay, check, compute_pseudo) \ | |
3034 | ({ \ | |
3035 | __sum16 __ret = 0; \ | |
5d0c2b95 | 3036 | skb->csum_valid = 0; \ |
76ba0aae TH |
3037 | if (__skb_checksum_validate_needed(skb, zero_okay, check)) \ |
3038 | __ret = __skb_checksum_validate_complete(skb, \ | |
3039 | complete, compute_pseudo(skb, proto)); \ | |
3040 | __ret; \ | |
3041 | }) | |
3042 | ||
3043 | #define skb_checksum_init(skb, proto, compute_pseudo) \ | |
3044 | __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo) | |
3045 | ||
3046 | #define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \ | |
3047 | __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo) | |
3048 | ||
3049 | #define skb_checksum_validate(skb, proto, compute_pseudo) \ | |
3050 | __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo) | |
3051 | ||
3052 | #define skb_checksum_validate_zero_check(skb, proto, check, \ | |
3053 | compute_pseudo) \ | |
3054 | __skb_checksum_validate_(skb, proto, true, true, check, compute_pseudo) | |
3055 | ||
3056 | #define skb_checksum_simple_validate(skb) \ | |
3057 | __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo) | |
3058 | ||
d96535a1 TH |
3059 | static inline bool __skb_checksum_convert_check(struct sk_buff *skb) |
3060 | { | |
3061 | return (skb->ip_summed == CHECKSUM_NONE && | |
3062 | skb->csum_valid && !skb->csum_bad); | |
3063 | } | |
3064 | ||
3065 | static inline void __skb_checksum_convert(struct sk_buff *skb, | |
3066 | __sum16 check, __wsum pseudo) | |
3067 | { | |
3068 | skb->csum = ~pseudo; | |
3069 | skb->ip_summed = CHECKSUM_COMPLETE; | |
3070 | } | |
3071 | ||
3072 | #define skb_checksum_try_convert(skb, proto, check, compute_pseudo) \ | |
3073 | do { \ | |
3074 | if (__skb_checksum_convert_check(skb)) \ | |
3075 | __skb_checksum_convert(skb, check, \ | |
3076 | compute_pseudo(skb, proto)); \ | |
3077 | } while (0) | |
3078 | ||
5f79e0f9 | 3079 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
7965bd4d | 3080 | void nf_conntrack_destroy(struct nf_conntrack *nfct); |
1da177e4 LT |
3081 | static inline void nf_conntrack_put(struct nf_conntrack *nfct) |
3082 | { | |
3083 | if (nfct && atomic_dec_and_test(&nfct->use)) | |
de6e05c4 | 3084 | nf_conntrack_destroy(nfct); |
1da177e4 LT |
3085 | } |
3086 | static inline void nf_conntrack_get(struct nf_conntrack *nfct) | |
3087 | { | |
3088 | if (nfct) | |
3089 | atomic_inc(&nfct->use); | |
3090 | } | |
2fc72c7b | 3091 | #endif |
34666d46 | 3092 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
1da177e4 LT |
3093 | static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) |
3094 | { | |
3095 | if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) | |
3096 | kfree(nf_bridge); | |
3097 | } | |
3098 | static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) | |
3099 | { | |
3100 | if (nf_bridge) | |
3101 | atomic_inc(&nf_bridge->use); | |
3102 | } | |
3103 | #endif /* CONFIG_BRIDGE_NETFILTER */ | |
a193a4ab PM |
3104 | static inline void nf_reset(struct sk_buff *skb) |
3105 | { | |
5f79e0f9 | 3106 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
a193a4ab PM |
3107 | nf_conntrack_put(skb->nfct); |
3108 | skb->nfct = NULL; | |
2fc72c7b | 3109 | #endif |
34666d46 | 3110 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
a193a4ab PM |
3111 | nf_bridge_put(skb->nf_bridge); |
3112 | skb->nf_bridge = NULL; | |
3113 | #endif | |
3114 | } | |
3115 | ||
124dff01 PM |
3116 | static inline void nf_reset_trace(struct sk_buff *skb) |
3117 | { | |
478b360a | 3118 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) |
130549fe G |
3119 | skb->nf_trace = 0; |
3120 | #endif | |
a193a4ab PM |
3121 | } |
3122 | ||
edda553c | 3123 | /* Note: This doesn't put any conntrack and bridge info in dst. */ |
b1937227 ED |
3124 | static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src, |
3125 | bool copy) | |
edda553c | 3126 | { |
5f79e0f9 | 3127 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
edda553c YK |
3128 | dst->nfct = src->nfct; |
3129 | nf_conntrack_get(src->nfct); | |
b1937227 ED |
3130 | if (copy) |
3131 | dst->nfctinfo = src->nfctinfo; | |
2fc72c7b | 3132 | #endif |
34666d46 | 3133 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
edda553c YK |
3134 | dst->nf_bridge = src->nf_bridge; |
3135 | nf_bridge_get(src->nf_bridge); | |
3136 | #endif | |
478b360a | 3137 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) |
b1937227 ED |
3138 | if (copy) |
3139 | dst->nf_trace = src->nf_trace; | |
478b360a | 3140 | #endif |
edda553c YK |
3141 | } |
3142 | ||
e7ac05f3 YK |
3143 | static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) |
3144 | { | |
e7ac05f3 | 3145 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
5f79e0f9 | 3146 | nf_conntrack_put(dst->nfct); |
2fc72c7b | 3147 | #endif |
34666d46 | 3148 | #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) |
e7ac05f3 YK |
3149 | nf_bridge_put(dst->nf_bridge); |
3150 | #endif | |
b1937227 | 3151 | __nf_copy(dst, src, true); |
e7ac05f3 YK |
3152 | } |
3153 | ||
984bc16c JM |
3154 | #ifdef CONFIG_NETWORK_SECMARK |
3155 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
3156 | { | |
3157 | to->secmark = from->secmark; | |
3158 | } | |
3159 | ||
3160 | static inline void skb_init_secmark(struct sk_buff *skb) | |
3161 | { | |
3162 | skb->secmark = 0; | |
3163 | } | |
3164 | #else | |
3165 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) | |
3166 | { } | |
3167 | ||
3168 | static inline void skb_init_secmark(struct sk_buff *skb) | |
3169 | { } | |
3170 | #endif | |
3171 | ||
574f7194 EB |
3172 | static inline bool skb_irq_freeable(const struct sk_buff *skb) |
3173 | { | |
3174 | return !skb->destructor && | |
3175 | #if IS_ENABLED(CONFIG_XFRM) | |
3176 | !skb->sp && | |
3177 | #endif | |
3178 | #if IS_ENABLED(CONFIG_NF_CONNTRACK) | |
3179 | !skb->nfct && | |
3180 | #endif | |
3181 | !skb->_skb_refdst && | |
3182 | !skb_has_frag_list(skb); | |
3183 | } | |
3184 | ||
f25f4e44 PWJ |
3185 | static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping) |
3186 | { | |
f25f4e44 | 3187 | skb->queue_mapping = queue_mapping; |
f25f4e44 PWJ |
3188 | } |
3189 | ||
9247744e | 3190 | static inline u16 skb_get_queue_mapping(const struct sk_buff *skb) |
4e3ab47a | 3191 | { |
4e3ab47a | 3192 | return skb->queue_mapping; |
4e3ab47a PE |
3193 | } |
3194 | ||
f25f4e44 PWJ |
3195 | static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from) |
3196 | { | |
f25f4e44 | 3197 | to->queue_mapping = from->queue_mapping; |
f25f4e44 PWJ |
3198 | } |
3199 | ||
d5a9e24a DM |
3200 | static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue) |
3201 | { | |
3202 | skb->queue_mapping = rx_queue + 1; | |
3203 | } | |
3204 | ||
9247744e | 3205 | static inline u16 skb_get_rx_queue(const struct sk_buff *skb) |
d5a9e24a DM |
3206 | { |
3207 | return skb->queue_mapping - 1; | |
3208 | } | |
3209 | ||
9247744e | 3210 | static inline bool skb_rx_queue_recorded(const struct sk_buff *skb) |
d5a9e24a | 3211 | { |
a02cec21 | 3212 | return skb->queue_mapping != 0; |
d5a9e24a DM |
3213 | } |
3214 | ||
0e001614 | 3215 | u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb, |
7965bd4d | 3216 | unsigned int num_tx_queues); |
9247744e | 3217 | |
def8b4fa AD |
3218 | static inline struct sec_path *skb_sec_path(struct sk_buff *skb) |
3219 | { | |
0b3d8e08 | 3220 | #ifdef CONFIG_XFRM |
def8b4fa | 3221 | return skb->sp; |
def8b4fa | 3222 | #else |
def8b4fa | 3223 | return NULL; |
def8b4fa | 3224 | #endif |
0b3d8e08 | 3225 | } |
def8b4fa | 3226 | |
68c33163 PS |
3227 | /* Keeps track of mac header offset relative to skb->head. |
3228 | * It is useful for TSO of Tunneling protocol. e.g. GRE. | |
3229 | * For non-tunnel skb it points to skb_mac_header() and for | |
3347c960 ED |
3230 | * tunnel skb it points to outer mac header. |
3231 | * Keeps track of level of encapsulation of network headers. | |
3232 | */ | |
68c33163 | 3233 | struct skb_gso_cb { |
3347c960 ED |
3234 | int mac_offset; |
3235 | int encap_level; | |
7e2b10c1 | 3236 | __u16 csum_start; |
68c33163 PS |
3237 | }; |
3238 | #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb) | |
3239 | ||
3240 | static inline int skb_tnl_header_len(const struct sk_buff *inner_skb) | |
3241 | { | |
3242 | return (skb_mac_header(inner_skb) - inner_skb->head) - | |
3243 | SKB_GSO_CB(inner_skb)->mac_offset; | |
3244 | } | |
3245 | ||
1e2bd517 PS |
3246 | static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra) |
3247 | { | |
3248 | int new_headroom, headroom; | |
3249 | int ret; | |
3250 | ||
3251 | headroom = skb_headroom(skb); | |
3252 | ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC); | |
3253 | if (ret) | |
3254 | return ret; | |
3255 | ||
3256 | new_headroom = skb_headroom(skb); | |
3257 | SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom); | |
3258 | return 0; | |
3259 | } | |
3260 | ||
7e2b10c1 TH |
3261 | /* Compute the checksum for a gso segment. First compute the checksum value |
3262 | * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and | |
3263 | * then add in skb->csum (checksum from csum_start to end of packet). | |
3264 | * skb->csum and csum_start are then updated to reflect the checksum of the | |
3265 | * resultant packet starting from the transport header-- the resultant checksum | |
3266 | * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo | |
3267 | * header. | |
3268 | */ | |
3269 | static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res) | |
3270 | { | |
3271 | int plen = SKB_GSO_CB(skb)->csum_start - skb_headroom(skb) - | |
3272 | skb_transport_offset(skb); | |
3273 | __u16 csum; | |
3274 | ||
3275 | csum = csum_fold(csum_partial(skb_transport_header(skb), | |
3276 | plen, skb->csum)); | |
3277 | skb->csum = res; | |
3278 | SKB_GSO_CB(skb)->csum_start -= plen; | |
3279 | ||
3280 | return csum; | |
3281 | } | |
3282 | ||
bdcc0924 | 3283 | static inline bool skb_is_gso(const struct sk_buff *skb) |
89114afd HX |
3284 | { |
3285 | return skb_shinfo(skb)->gso_size; | |
3286 | } | |
3287 | ||
36a8f39e | 3288 | /* Note: Should be called only if skb_is_gso(skb) is true */ |
bdcc0924 | 3289 | static inline bool skb_is_gso_v6(const struct sk_buff *skb) |
eabd7e35 BG |
3290 | { |
3291 | return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6; | |
3292 | } | |
3293 | ||
7965bd4d | 3294 | void __skb_warn_lro_forwarding(const struct sk_buff *skb); |
4497b076 BH |
3295 | |
3296 | static inline bool skb_warn_if_lro(const struct sk_buff *skb) | |
3297 | { | |
3298 | /* LRO sets gso_size but not gso_type, whereas if GSO is really | |
3299 | * wanted then gso_type will be set. */ | |
05bdd2f1 ED |
3300 | const struct skb_shared_info *shinfo = skb_shinfo(skb); |
3301 | ||
b78462eb AD |
3302 | if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 && |
3303 | unlikely(shinfo->gso_type == 0)) { | |
4497b076 BH |
3304 | __skb_warn_lro_forwarding(skb); |
3305 | return true; | |
3306 | } | |
3307 | return false; | |
3308 | } | |
3309 | ||
35fc92a9 HX |
3310 | static inline void skb_forward_csum(struct sk_buff *skb) |
3311 | { | |
3312 | /* Unfortunately we don't support this one. Any brave souls? */ | |
3313 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
3314 | skb->ip_summed = CHECKSUM_NONE; | |
3315 | } | |
3316 | ||
bc8acf2c ED |
3317 | /** |
3318 | * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE | |
3319 | * @skb: skb to check | |
3320 | * | |
3321 | * fresh skbs have their ip_summed set to CHECKSUM_NONE. | |
3322 | * Instead of forcing ip_summed to CHECKSUM_NONE, we can | |
3323 | * use this helper, to document places where we make this assertion. | |
3324 | */ | |
05bdd2f1 | 3325 | static inline void skb_checksum_none_assert(const struct sk_buff *skb) |
bc8acf2c ED |
3326 | { |
3327 | #ifdef DEBUG | |
3328 | BUG_ON(skb->ip_summed != CHECKSUM_NONE); | |
3329 | #endif | |
3330 | } | |
3331 | ||
f35d9d8a | 3332 | bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); |
a6686f2f | 3333 | |
ed1f50c3 PD |
3334 | int skb_checksum_setup(struct sk_buff *skb, bool recalculate); |
3335 | ||
56193d1b AD |
3336 | u32 skb_get_poff(const struct sk_buff *skb); |
3337 | u32 __skb_get_poff(const struct sk_buff *skb, void *data, | |
3338 | const struct flow_keys *keys, int hlen); | |
f77668dc | 3339 | |
3a7c1ee4 AD |
3340 | /** |
3341 | * skb_head_is_locked - Determine if the skb->head is locked down | |
3342 | * @skb: skb to check | |
3343 | * | |
3344 | * The head on skbs build around a head frag can be removed if they are | |
3345 | * not cloned. This function returns true if the skb head is locked down | |
3346 | * due to either being allocated via kmalloc, or by being a clone with | |
3347 | * multiple references to the head. | |
3348 | */ | |
3349 | static inline bool skb_head_is_locked(const struct sk_buff *skb) | |
3350 | { | |
3351 | return !skb->head_frag || skb_cloned(skb); | |
3352 | } | |
fe6cc55f FW |
3353 | |
3354 | /** | |
3355 | * skb_gso_network_seglen - Return length of individual segments of a gso packet | |
3356 | * | |
3357 | * @skb: GSO skb | |
3358 | * | |
3359 | * skb_gso_network_seglen is used to determine the real size of the | |
3360 | * individual segments, including Layer3 (IP, IPv6) and L4 headers (TCP/UDP). | |
3361 | * | |
3362 | * The MAC/L2 header is not accounted for. | |
3363 | */ | |
3364 | static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb) | |
3365 | { | |
3366 | unsigned int hdr_len = skb_transport_header(skb) - | |
3367 | skb_network_header(skb); | |
3368 | return hdr_len + skb_gso_transport_seglen(skb); | |
3369 | } | |
1da177e4 LT |
3370 | #endif /* __KERNEL__ */ |
3371 | #endif /* _LINUX_SKBUFF_H */ |