Merge tag '5.15-rc-cifs-part2' of git://git.samba.org/sfrench/cifs-2.6
[linux-block.git] / include / linux / skmsg.h
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1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
3
4#ifndef _LINUX_SKMSG_H
5#define _LINUX_SKMSG_H
6
7#include <linux/bpf.h>
8#include <linux/filter.h>
9#include <linux/scatterlist.h>
10#include <linux/skbuff.h>
11
12#include <net/sock.h>
13#include <net/tcp.h>
14#include <net/strparser.h>
15
16#define MAX_MSG_FRAGS MAX_SKB_FRAGS
031097d9 17#define NR_MSG_FRAG_IDS (MAX_MSG_FRAGS + 1)
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18
19enum __sk_action {
20 __SK_DROP = 0,
21 __SK_PASS,
22 __SK_REDIRECT,
23 __SK_NONE,
24};
25
26struct sk_msg_sg {
27 u32 start;
28 u32 curr;
29 u32 end;
30 u32 size;
31 u32 copybreak;
163ab96b 32 unsigned long copy;
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33 /* The extra two elements:
34 * 1) used for chaining the front and sections when the list becomes
35 * partitioned (e.g. end < start). The crypto APIs require the
36 * chaining;
37 * 2) to chain tailer SG entries after the message.
d3b18ad3 38 */
031097d9 39 struct scatterlist data[MAX_MSG_FRAGS + 2];
604326b4 40};
031097d9 41static_assert(BITS_PER_LONG >= NR_MSG_FRAG_IDS);
604326b4 42
7a69c0f2 43/* UAPI in filter.c depends on struct sk_msg_sg being first element. */
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44struct sk_msg {
45 struct sk_msg_sg sg;
46 void *data;
47 void *data_end;
48 u32 apply_bytes;
49 u32 cork_bytes;
50 u32 flags;
51 struct sk_buff *skb;
52 struct sock *sk_redir;
53 struct sock *sk;
54 struct list_head list;
55};
56
57struct sk_psock_progs {
58 struct bpf_prog *msg_parser;
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59 struct bpf_prog *stream_parser;
60 struct bpf_prog *stream_verdict;
a7ba4558 61 struct bpf_prog *skb_verdict;
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62};
63
64enum sk_psock_state_bits {
65 SK_PSOCK_TX_ENABLED,
66};
67
68struct sk_psock_link {
69 struct list_head list;
70 struct bpf_map *map;
71 void *link_raw;
72};
73
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74struct sk_psock_work_state {
75 struct sk_buff *skb;
76 u32 len;
77 u32 off;
78};
79
80struct sk_psock {
81 struct sock *sk;
82 struct sock *sk_redir;
83 u32 apply_bytes;
84 u32 cork_bytes;
85 u32 eval;
86 struct sk_msg *cork;
87 struct sk_psock_progs progs;
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88#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
89 struct strparser strp;
90#endif
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91 struct sk_buff_head ingress_skb;
92 struct list_head ingress_msg;
b01fd6e8 93 spinlock_t ingress_lock;
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94 unsigned long state;
95 struct list_head link;
96 spinlock_t link_lock;
97 refcount_t refcnt;
98 void (*saved_unhash)(struct sock *sk);
99 void (*saved_close)(struct sock *sk, long timeout);
100 void (*saved_write_space)(struct sock *sk);
5a685cd9 101 void (*saved_data_ready)(struct sock *sk);
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102 int (*psock_update_sk_prot)(struct sock *sk, struct sk_psock *psock,
103 bool restore);
604326b4 104 struct proto *sk_proto;
799aa7f9 105 struct mutex work_mutex;
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106 struct sk_psock_work_state work_state;
107 struct work_struct work;
7786dfc4 108 struct rcu_work rwork;
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109};
110
111int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
112 int elem_first_coalesce);
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113int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
114 u32 off, u32 len);
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115void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len);
116int sk_msg_free(struct sock *sk, struct sk_msg *msg);
117int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg);
118void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes);
119void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
120 u32 bytes);
121
122void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes);
d3b18ad3 123void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes);
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124
125int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
126 struct sk_msg *msg, u32 bytes);
127int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
128 struct sk_msg *msg, u32 bytes);
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129int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
130 int len, int flags);
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131
132static inline void sk_msg_check_to_free(struct sk_msg *msg, u32 i, u32 bytes)
133{
134 WARN_ON(i == msg->sg.end && bytes);
135}
136
137static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
138{
139 if (psock->apply_bytes) {
140 if (psock->apply_bytes < bytes)
141 psock->apply_bytes = 0;
142 else
143 psock->apply_bytes -= bytes;
144 }
145}
146
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147static inline u32 sk_msg_iter_dist(u32 start, u32 end)
148{
031097d9 149 return end >= start ? end - start : end + (NR_MSG_FRAG_IDS - start);
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150}
151
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152#define sk_msg_iter_var_prev(var) \
153 do { \
154 if (var == 0) \
031097d9 155 var = NR_MSG_FRAG_IDS - 1; \
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156 else \
157 var--; \
158 } while (0)
159
160#define sk_msg_iter_var_next(var) \
161 do { \
162 var++; \
031097d9 163 if (var == NR_MSG_FRAG_IDS) \
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164 var = 0; \
165 } while (0)
166
167#define sk_msg_iter_prev(msg, which) \
168 sk_msg_iter_var_prev(msg->sg.which)
169
170#define sk_msg_iter_next(msg, which) \
171 sk_msg_iter_var_next(msg->sg.which)
172
173static inline void sk_msg_clear_meta(struct sk_msg *msg)
174{
175 memset(&msg->sg, 0, offsetofend(struct sk_msg_sg, copy));
176}
177
178static inline void sk_msg_init(struct sk_msg *msg)
179{
031097d9 180 BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != NR_MSG_FRAG_IDS);
604326b4 181 memset(msg, 0, sizeof(*msg));
031097d9 182 sg_init_marker(msg->sg.data, NR_MSG_FRAG_IDS);
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183}
184
185static inline void sk_msg_xfer(struct sk_msg *dst, struct sk_msg *src,
186 int which, u32 size)
187{
188 dst->sg.data[which] = src->sg.data[which];
189 dst->sg.data[which].length = size;
3f4c3127 190 dst->sg.size += size;
81aabbb9 191 src->sg.size -= size;
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192 src->sg.data[which].length -= size;
193 src->sg.data[which].offset += size;
194}
195
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196static inline void sk_msg_xfer_full(struct sk_msg *dst, struct sk_msg *src)
197{
198 memcpy(dst, src, sizeof(*src));
199 sk_msg_init(src);
200}
201
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202static inline bool sk_msg_full(const struct sk_msg *msg)
203{
031097d9 204 return sk_msg_iter_dist(msg->sg.start, msg->sg.end) == MAX_MSG_FRAGS;
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205}
206
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207static inline u32 sk_msg_elem_used(const struct sk_msg *msg)
208{
683916f6 209 return sk_msg_iter_dist(msg->sg.start, msg->sg.end);
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210}
211
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212static inline struct scatterlist *sk_msg_elem(struct sk_msg *msg, int which)
213{
214 return &msg->sg.data[which];
215}
216
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217static inline struct scatterlist sk_msg_elem_cpy(struct sk_msg *msg, int which)
218{
219 return msg->sg.data[which];
220}
221
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222static inline struct page *sk_msg_page(struct sk_msg *msg, int which)
223{
224 return sg_page(sk_msg_elem(msg, which));
225}
226
227static inline bool sk_msg_to_ingress(const struct sk_msg *msg)
228{
229 return msg->flags & BPF_F_INGRESS;
230}
231
232static inline void sk_msg_compute_data_pointers(struct sk_msg *msg)
233{
234 struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start);
235
163ab96b 236 if (test_bit(msg->sg.start, &msg->sg.copy)) {
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237 msg->data = NULL;
238 msg->data_end = NULL;
239 } else {
240 msg->data = sg_virt(sge);
241 msg->data_end = msg->data + sge->length;
242 }
243}
244
245static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page,
246 u32 len, u32 offset)
247{
248 struct scatterlist *sge;
249
250 get_page(page);
251 sge = sk_msg_elem(msg, msg->sg.end);
252 sg_set_page(sge, page, len, offset);
253 sg_unmark_end(sge);
254
163ab96b 255 __set_bit(msg->sg.end, &msg->sg.copy);
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256 msg->sg.size += len;
257 sk_msg_iter_next(msg, end);
258}
259
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260static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state)
261{
262 do {
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263 if (copy_state)
264 __set_bit(i, &msg->sg.copy);
265 else
266 __clear_bit(i, &msg->sg.copy);
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267 sk_msg_iter_var_next(i);
268 if (i == msg->sg.end)
269 break;
270 } while (1);
271}
272
273static inline void sk_msg_sg_copy_set(struct sk_msg *msg, u32 start)
274{
275 sk_msg_sg_copy(msg, start, true);
276}
277
278static inline void sk_msg_sg_copy_clear(struct sk_msg *msg, u32 start)
279{
280 sk_msg_sg_copy(msg, start, false);
281}
282
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283static inline struct sk_psock *sk_psock(const struct sock *sk)
284{
285 return rcu_dereference_sk_user_data(sk);
286}
287
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288static inline void sk_psock_set_state(struct sk_psock *psock,
289 enum sk_psock_state_bits bit)
290{
291 set_bit(bit, &psock->state);
292}
293
294static inline void sk_psock_clear_state(struct sk_psock *psock,
295 enum sk_psock_state_bits bit)
296{
297 clear_bit(bit, &psock->state);
298}
299
300static inline bool sk_psock_test_state(const struct sk_psock *psock,
301 enum sk_psock_state_bits bit)
302{
303 return test_bit(bit, &psock->state);
304}
305
306static inline void sock_drop(struct sock *sk, struct sk_buff *skb)
307{
308 sk_drops_add(sk, skb);
309 kfree_skb(skb);
310}
311
312static inline void drop_sk_msg(struct sk_psock *psock, struct sk_msg *msg)
313{
314 if (msg->skb)
315 sock_drop(psock->sk, msg->skb);
316 kfree(msg);
317}
318
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319static inline void sk_psock_queue_msg(struct sk_psock *psock,
320 struct sk_msg *msg)
321{
b01fd6e8 322 spin_lock_bh(&psock->ingress_lock);
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323 if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED))
324 list_add_tail(&msg->list, &psock->ingress_msg);
325 else
326 drop_sk_msg(psock, msg);
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327 spin_unlock_bh(&psock->ingress_lock);
328}
329
330static inline struct sk_msg *sk_psock_dequeue_msg(struct sk_psock *psock)
331{
332 struct sk_msg *msg;
333
334 spin_lock_bh(&psock->ingress_lock);
335 msg = list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
336 if (msg)
337 list_del(&msg->list);
338 spin_unlock_bh(&psock->ingress_lock);
339 return msg;
340}
341
342static inline struct sk_msg *sk_psock_peek_msg(struct sk_psock *psock)
343{
344 struct sk_msg *msg;
345
346 spin_lock_bh(&psock->ingress_lock);
347 msg = list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
348 spin_unlock_bh(&psock->ingress_lock);
349 return msg;
350}
351
352static inline struct sk_msg *sk_psock_next_msg(struct sk_psock *psock,
353 struct sk_msg *msg)
354{
355 struct sk_msg *ret;
356
357 spin_lock_bh(&psock->ingress_lock);
358 if (list_is_last(&msg->list, &psock->ingress_msg))
359 ret = NULL;
360 else
361 ret = list_next_entry(msg, list);
362 spin_unlock_bh(&psock->ingress_lock);
363 return ret;
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364}
365
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366static inline bool sk_psock_queue_empty(const struct sk_psock *psock)
367{
368 return psock ? list_empty(&psock->ingress_msg) : true;
369}
370
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371static inline void kfree_sk_msg(struct sk_msg *msg)
372{
373 if (msg->skb)
374 consume_skb(msg->skb);
375 kfree(msg);
376}
377
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378static inline void sk_psock_report_error(struct sk_psock *psock, int err)
379{
380 struct sock *sk = psock->sk;
381
382 sk->sk_err = err;
e3ae2365 383 sk_error_report(sk);
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384}
385
386struct sk_psock *sk_psock_init(struct sock *sk, int node);
799aa7f9 387void sk_psock_stop(struct sk_psock *psock, bool wait);
604326b4 388
88759609 389#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
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390int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock);
391void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock);
392void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock);
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393#else
394static inline int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
395{
396 return -EOPNOTSUPP;
397}
398
399static inline void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
400{
401}
402
403static inline void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
404{
405}
406#endif
407
ef565928
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408void sk_psock_start_verdict(struct sock *sk, struct sk_psock *psock);
409void sk_psock_stop_verdict(struct sock *sk, struct sk_psock *psock);
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410
411int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
412 struct sk_msg *msg);
413
414static inline struct sk_psock_link *sk_psock_init_link(void)
415{
416 return kzalloc(sizeof(struct sk_psock_link),
417 GFP_ATOMIC | __GFP_NOWARN);
418}
419
420static inline void sk_psock_free_link(struct sk_psock_link *link)
421{
422 kfree(link);
423}
424
425struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock);
604326b4 426
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427static inline void sk_psock_cork_free(struct sk_psock *psock)
428{
429 if (psock->cork) {
430 sk_msg_free(psock->sk, psock->cork);
431 kfree(psock->cork);
432 psock->cork = NULL;
433 }
434}
435
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436static inline void sk_psock_restore_proto(struct sock *sk,
437 struct sk_psock *psock)
438{
8a59f9d1 439 if (psock->psock_update_sk_prot)
51e0158a 440 psock->psock_update_sk_prot(sk, psock, true);
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441}
442
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443static inline struct sk_psock *sk_psock_get(struct sock *sk)
444{
445 struct sk_psock *psock;
446
447 rcu_read_lock();
448 psock = sk_psock(sk);
449 if (psock && !refcount_inc_not_zero(&psock->refcnt))
450 psock = NULL;
451 rcu_read_unlock();
452 return psock;
453}
454
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455void sk_psock_drop(struct sock *sk, struct sk_psock *psock);
456
457static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
458{
459 if (refcount_dec_and_test(&psock->refcnt))
460 sk_psock_drop(sk, psock);
461}
462
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463static inline void sk_psock_data_ready(struct sock *sk, struct sk_psock *psock)
464{
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465 if (psock->saved_data_ready)
466 psock->saved_data_ready(sk);
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467 else
468 sk->sk_data_ready(sk);
469}
470
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471static inline void psock_set_prog(struct bpf_prog **pprog,
472 struct bpf_prog *prog)
473{
474 prog = xchg(pprog, prog);
475 if (prog)
476 bpf_prog_put(prog);
477}
478
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479static inline int psock_replace_prog(struct bpf_prog **pprog,
480 struct bpf_prog *prog,
481 struct bpf_prog *old)
482{
483 if (cmpxchg(pprog, old, prog) != old)
484 return -ENOENT;
485
486 if (old)
487 bpf_prog_put(old);
488
489 return 0;
490}
491
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492static inline void psock_progs_drop(struct sk_psock_progs *progs)
493{
494 psock_set_prog(&progs->msg_parser, NULL);
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495 psock_set_prog(&progs->stream_parser, NULL);
496 psock_set_prog(&progs->stream_verdict, NULL);
a7ba4558 497 psock_set_prog(&progs->skb_verdict, NULL);
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498}
499
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500int sk_psock_tls_strp_read(struct sk_psock *psock, struct sk_buff *skb);
501
502static inline bool sk_psock_strp_enabled(struct sk_psock *psock)
503{
504 if (!psock)
505 return false;
5a685cd9 506 return !!psock->saved_data_ready;
e91de6af 507}
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508
509#if IS_ENABLED(CONFIG_NET_SOCK_MSG)
510
511/* We only have one bit so far. */
512#define BPF_F_PTR_MASK ~(BPF_F_INGRESS)
513
514static inline bool skb_bpf_ingress(const struct sk_buff *skb)
515{
516 unsigned long sk_redir = skb->_sk_redir;
517
518 return sk_redir & BPF_F_INGRESS;
519}
520
521static inline void skb_bpf_set_ingress(struct sk_buff *skb)
522{
523 skb->_sk_redir |= BPF_F_INGRESS;
524}
525
526static inline void skb_bpf_set_redir(struct sk_buff *skb, struct sock *sk_redir,
527 bool ingress)
528{
529 skb->_sk_redir = (unsigned long)sk_redir;
530 if (ingress)
531 skb->_sk_redir |= BPF_F_INGRESS;
532}
533
534static inline struct sock *skb_bpf_redirect_fetch(const struct sk_buff *skb)
535{
536 unsigned long sk_redir = skb->_sk_redir;
537
538 return (struct sock *)(sk_redir & BPF_F_PTR_MASK);
539}
540
541static inline void skb_bpf_redirect_clear(struct sk_buff *skb)
542{
543 skb->_sk_redir = 0;
544}
545#endif /* CONFIG_NET_SOCK_MSG */
604326b4 546#endif /* _LINUX_SKMSG_H */