xref: /linux/include/linux/skmsg.h (revision 8934827db5403eae57d4537114a9ff88b0a8460f)
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
17 #define NR_MSG_FRAG_IDS			(MAX_MSG_FRAGS + 1)
18 
19 enum __sk_action {
20 	__SK_DROP = 0,
21 	__SK_PASS,
22 	__SK_REDIRECT,
23 	__SK_NONE,
24 };
25 
26 struct sk_msg_sg {
27 	u32				start;
28 	u32				curr;
29 	u32				end;
30 	u32				size;
31 	u32				copybreak;
32 	DECLARE_BITMAP(copy, MAX_MSG_FRAGS + 2);
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.
38 	 */
39 	struct scatterlist		data[MAX_MSG_FRAGS + 2];
40 };
41 
42 /* UAPI in filter.c depends on struct sk_msg_sg being first element. */
43 struct sk_msg {
44 	struct sk_msg_sg		sg;
45 	void				*data;
46 	void				*data_end;
47 	u32				apply_bytes;
48 	u32				cork_bytes;
49 	u32				flags;
50 	struct sk_buff			*skb;
51 	struct sock			*sk_redir;
52 	struct sock			*sk;
53 	struct list_head		list;
54 };
55 
56 struct sk_psock_progs {
57 	struct bpf_prog			*msg_parser;
58 	struct bpf_prog			*stream_parser;
59 	struct bpf_prog			*stream_verdict;
60 	struct bpf_prog			*skb_verdict;
61 	struct bpf_link			*msg_parser_link;
62 	struct bpf_link			*stream_parser_link;
63 	struct bpf_link			*stream_verdict_link;
64 	struct bpf_link			*skb_verdict_link;
65 };
66 
67 enum sk_psock_state_bits {
68 	SK_PSOCK_TX_ENABLED,
69 	SK_PSOCK_RX_STRP_ENABLED,
70 };
71 
72 struct sk_psock_link {
73 	struct list_head		list;
74 	struct bpf_map			*map;
75 	void				*link_raw;
76 };
77 
78 struct sk_psock_work_state {
79 	u32				len;
80 	u32				off;
81 };
82 
83 struct sk_psock {
84 	struct sock			*sk;
85 	struct sock			*sk_redir;
86 	u32				apply_bytes;
87 	u32				cork_bytes;
88 	u32				eval;
89 	bool				redir_ingress; /* undefined if sk_redir is null */
90 	struct sk_msg			*cork;
91 	struct sk_psock_progs		progs;
92 #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
93 	struct strparser		strp;
94 	u32				copied_seq;
95 	u32				ingress_bytes;
96 #endif
97 	struct sk_buff_head		ingress_skb;
98 	struct list_head		ingress_msg;
99 	spinlock_t			ingress_lock;
100 	/** @msg_tot_len: Total bytes queued in ingress_msg list. */
101 	u32				msg_tot_len;
102 	unsigned long			state;
103 	struct list_head		link;
104 	spinlock_t			link_lock;
105 	refcount_t			refcnt;
106 	void (*saved_unhash)(struct sock *sk);
107 	void (*saved_destroy)(struct sock *sk);
108 	void (*saved_close)(struct sock *sk, long timeout);
109 	void (*saved_write_space)(struct sock *sk);
110 	void (*saved_data_ready)(struct sock *sk);
111 	/* psock_update_sk_prot may be called with restore=false many times
112 	 * so the handler must be safe for this case. It will be called
113 	 * exactly once with restore=true when the psock is being destroyed
114 	 * and psock refcnt is zero, but before an RCU grace period.
115 	 */
116 	int  (*psock_update_sk_prot)(struct sock *sk, struct sk_psock *psock,
117 				     bool restore);
118 	struct proto			*sk_proto;
119 	struct mutex			work_mutex;
120 	struct sk_psock_work_state	work_state;
121 	struct delayed_work		work;
122 	struct sock			*sk_pair;
123 	struct rcu_work			rwork;
124 };
125 
126 int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
127 		 int elem_first_coalesce);
128 int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
129 		 u32 off, u32 len);
130 void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len);
131 int sk_msg_free(struct sock *sk, struct sk_msg *msg);
132 int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg);
133 void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes);
134 void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
135 				  u32 bytes);
136 
137 void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes);
138 void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes);
139 
140 int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
141 			      struct sk_msg *msg, u32 bytes);
142 int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
143 			     struct sk_msg *msg, u32 bytes);
144 int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
145 		   int len, int flags);
146 int __sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
147 		     int len, int flags, int *copied_from_self);
148 bool sk_msg_is_readable(struct sock *sk);
149 
sk_msg_check_to_free(struct sk_msg * msg,u32 i,u32 bytes)150 static inline void sk_msg_check_to_free(struct sk_msg *msg, u32 i, u32 bytes)
151 {
152 	WARN_ON(i == msg->sg.end && bytes);
153 }
154 
sk_msg_apply_bytes(struct sk_psock * psock,u32 bytes)155 static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
156 {
157 	if (psock->apply_bytes) {
158 		if (psock->apply_bytes < bytes)
159 			psock->apply_bytes = 0;
160 		else
161 			psock->apply_bytes -= bytes;
162 	}
163 }
164 
sk_msg_iter_dist(u32 start,u32 end)165 static inline u32 sk_msg_iter_dist(u32 start, u32 end)
166 {
167 	return end >= start ? end - start : end + (NR_MSG_FRAG_IDS - start);
168 }
169 
170 #define sk_msg_iter_var_prev(var)			\
171 	do {						\
172 		if (var == 0)				\
173 			var = NR_MSG_FRAG_IDS - 1;	\
174 		else					\
175 			var--;				\
176 	} while (0)
177 
178 #define sk_msg_iter_var_next(var)			\
179 	do {						\
180 		var++;					\
181 		if (var == NR_MSG_FRAG_IDS)		\
182 			var = 0;			\
183 	} while (0)
184 
185 #define sk_msg_iter_prev(msg, which)			\
186 	sk_msg_iter_var_prev(msg->sg.which)
187 
188 #define sk_msg_iter_next(msg, which)			\
189 	sk_msg_iter_var_next(msg->sg.which)
190 
sk_msg_init(struct sk_msg * msg)191 static inline void sk_msg_init(struct sk_msg *msg)
192 {
193 	BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != NR_MSG_FRAG_IDS);
194 	memset(msg, 0, sizeof(*msg));
195 	sg_init_marker(msg->sg.data, NR_MSG_FRAG_IDS);
196 }
197 
sk_msg_xfer(struct sk_msg * dst,struct sk_msg * src,int which,u32 size)198 static inline void sk_msg_xfer(struct sk_msg *dst, struct sk_msg *src,
199 			       int which, u32 size)
200 {
201 	dst->sg.data[which] = src->sg.data[which];
202 	dst->sg.data[which].length  = size;
203 	dst->sg.size		   += size;
204 	src->sg.size		   -= size;
205 	src->sg.data[which].length -= size;
206 	src->sg.data[which].offset += size;
207 }
208 
sk_msg_xfer_full(struct sk_msg * dst,struct sk_msg * src)209 static inline void sk_msg_xfer_full(struct sk_msg *dst, struct sk_msg *src)
210 {
211 	memcpy(dst, src, sizeof(*src));
212 	sk_msg_init(src);
213 }
214 
sk_msg_full(const struct sk_msg * msg)215 static inline bool sk_msg_full(const struct sk_msg *msg)
216 {
217 	return sk_msg_iter_dist(msg->sg.start, msg->sg.end) == MAX_MSG_FRAGS;
218 }
219 
sk_msg_elem_used(const struct sk_msg * msg)220 static inline u32 sk_msg_elem_used(const struct sk_msg *msg)
221 {
222 	return sk_msg_iter_dist(msg->sg.start, msg->sg.end);
223 }
224 
sk_msg_elem(struct sk_msg * msg,int which)225 static inline struct scatterlist *sk_msg_elem(struct sk_msg *msg, int which)
226 {
227 	return &msg->sg.data[which];
228 }
229 
sk_msg_elem_cpy(struct sk_msg * msg,int which)230 static inline struct scatterlist sk_msg_elem_cpy(struct sk_msg *msg, int which)
231 {
232 	return msg->sg.data[which];
233 }
234 
sk_msg_page(struct sk_msg * msg,int which)235 static inline struct page *sk_msg_page(struct sk_msg *msg, int which)
236 {
237 	return sg_page(sk_msg_elem(msg, which));
238 }
239 
sk_msg_to_ingress(const struct sk_msg * msg)240 static inline bool sk_msg_to_ingress(const struct sk_msg *msg)
241 {
242 	return msg->flags & BPF_F_INGRESS;
243 }
244 
sk_msg_compute_data_pointers(struct sk_msg * msg)245 static inline void sk_msg_compute_data_pointers(struct sk_msg *msg)
246 {
247 	struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start);
248 
249 	if (test_bit(msg->sg.start, msg->sg.copy)) {
250 		msg->data = NULL;
251 		msg->data_end = NULL;
252 	} else {
253 		msg->data = sg_virt(sge);
254 		msg->data_end = msg->data + sge->length;
255 	}
256 }
257 
sk_msg_page_add(struct sk_msg * msg,struct page * page,u32 len,u32 offset)258 static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page,
259 				   u32 len, u32 offset)
260 {
261 	struct scatterlist *sge;
262 
263 	get_page(page);
264 	sge = sk_msg_elem(msg, msg->sg.end);
265 	sg_set_page(sge, page, len, offset);
266 	sg_unmark_end(sge);
267 
268 	__set_bit(msg->sg.end, msg->sg.copy);
269 	msg->sg.size += len;
270 	sk_msg_iter_next(msg, end);
271 }
272 
sk_msg_sg_copy(struct sk_msg * msg,u32 i,bool copy_state)273 static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state)
274 {
275 	do {
276 		if (copy_state)
277 			__set_bit(i, msg->sg.copy);
278 		else
279 			__clear_bit(i, msg->sg.copy);
280 		sk_msg_iter_var_next(i);
281 		if (i == msg->sg.end)
282 			break;
283 	} while (1);
284 }
285 
sk_msg_sg_copy_set(struct sk_msg * msg,u32 start)286 static inline void sk_msg_sg_copy_set(struct sk_msg *msg, u32 start)
287 {
288 	sk_msg_sg_copy(msg, start, true);
289 }
290 
sk_msg_sg_copy_clear(struct sk_msg * msg,u32 start)291 static inline void sk_msg_sg_copy_clear(struct sk_msg *msg, u32 start)
292 {
293 	sk_msg_sg_copy(msg, start, false);
294 }
295 
sk_psock(const struct sock * sk)296 static inline struct sk_psock *sk_psock(const struct sock *sk)
297 {
298 	return __rcu_dereference_sk_user_data_with_flags(sk,
299 							 SK_USER_DATA_PSOCK);
300 }
301 
sk_psock_set_state(struct sk_psock * psock,enum sk_psock_state_bits bit)302 static inline void sk_psock_set_state(struct sk_psock *psock,
303 				      enum sk_psock_state_bits bit)
304 {
305 	set_bit(bit, &psock->state);
306 }
307 
sk_psock_clear_state(struct sk_psock * psock,enum sk_psock_state_bits bit)308 static inline void sk_psock_clear_state(struct sk_psock *psock,
309 					enum sk_psock_state_bits bit)
310 {
311 	clear_bit(bit, &psock->state);
312 }
313 
sk_psock_test_state(const struct sk_psock * psock,enum sk_psock_state_bits bit)314 static inline bool sk_psock_test_state(const struct sk_psock *psock,
315 				       enum sk_psock_state_bits bit)
316 {
317 	return test_bit(bit, &psock->state);
318 }
319 
sock_drop(struct sock * sk,struct sk_buff * skb)320 static inline void sock_drop(struct sock *sk, struct sk_buff *skb)
321 {
322 	sk_drops_skbadd(sk, skb);
323 	kfree_skb(skb);
324 }
325 
sk_psock_get_msg_len_nolock(struct sk_psock * psock)326 static inline u32 sk_psock_get_msg_len_nolock(struct sk_psock *psock)
327 {
328 	/* Used by ioctl to read msg_tot_len only; lock-free for performance */
329 	return READ_ONCE(psock->msg_tot_len);
330 }
331 
sk_psock_msg_len_add_locked(struct sk_psock * psock,int diff)332 static inline void sk_psock_msg_len_add_locked(struct sk_psock *psock, int diff)
333 {
334 	/* Use WRITE_ONCE to ensure correct read in sk_psock_get_msg_len_nolock().
335 	 * ingress_lock should be held to prevent concurrent updates to msg_tot_len
336 	 */
337 	WRITE_ONCE(psock->msg_tot_len, psock->msg_tot_len + diff);
338 }
339 
sk_psock_msg_len_add(struct sk_psock * psock,int diff)340 static inline void sk_psock_msg_len_add(struct sk_psock *psock, int diff)
341 {
342 	spin_lock_bh(&psock->ingress_lock);
343 	sk_psock_msg_len_add_locked(psock, diff);
344 	spin_unlock_bh(&psock->ingress_lock);
345 }
346 
sk_psock_queue_msg(struct sk_psock * psock,struct sk_msg * msg)347 static inline bool sk_psock_queue_msg(struct sk_psock *psock,
348 				      struct sk_msg *msg)
349 {
350 	bool ret;
351 
352 	spin_lock_bh(&psock->ingress_lock);
353 	if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)) {
354 		list_add_tail(&msg->list, &psock->ingress_msg);
355 		sk_psock_msg_len_add_locked(psock, msg->sg.size);
356 		ret = true;
357 	} else {
358 		sk_msg_free(psock->sk, msg);
359 		kfree(msg);
360 		ret = false;
361 	}
362 	spin_unlock_bh(&psock->ingress_lock);
363 	return ret;
364 }
365 
sk_psock_dequeue_msg(struct sk_psock * psock)366 static inline struct sk_msg *sk_psock_dequeue_msg(struct sk_psock *psock)
367 {
368 	struct sk_msg *msg;
369 
370 	spin_lock_bh(&psock->ingress_lock);
371 	msg = list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
372 	if (msg) {
373 		list_del(&msg->list);
374 		sk_psock_msg_len_add_locked(psock, -msg->sg.size);
375 	}
376 	spin_unlock_bh(&psock->ingress_lock);
377 	return msg;
378 }
379 
sk_psock_peek_msg_locked(struct sk_psock * psock)380 static inline struct sk_msg *sk_psock_peek_msg_locked(struct sk_psock *psock)
381 {
382 	return list_first_entry_or_null(&psock->ingress_msg, struct sk_msg, list);
383 }
384 
sk_psock_peek_msg(struct sk_psock * psock)385 static inline struct sk_msg *sk_psock_peek_msg(struct sk_psock *psock)
386 {
387 	struct sk_msg *msg;
388 
389 	spin_lock_bh(&psock->ingress_lock);
390 	msg = sk_psock_peek_msg_locked(psock);
391 	spin_unlock_bh(&psock->ingress_lock);
392 	return msg;
393 }
394 
sk_psock_next_msg(struct sk_psock * psock,struct sk_msg * msg)395 static inline struct sk_msg *sk_psock_next_msg(struct sk_psock *psock,
396 					       struct sk_msg *msg)
397 {
398 	struct sk_msg *ret;
399 
400 	spin_lock_bh(&psock->ingress_lock);
401 	if (list_is_last(&msg->list, &psock->ingress_msg))
402 		ret = NULL;
403 	else
404 		ret = list_next_entry(msg, list);
405 	spin_unlock_bh(&psock->ingress_lock);
406 	return ret;
407 }
408 
sk_psock_queue_empty(const struct sk_psock * psock)409 static inline bool sk_psock_queue_empty(const struct sk_psock *psock)
410 {
411 	return psock ? list_empty(&psock->ingress_msg) : true;
412 }
413 
kfree_sk_msg(struct sk_msg * msg)414 static inline void kfree_sk_msg(struct sk_msg *msg)
415 {
416 	if (msg->skb)
417 		consume_skb(msg->skb);
418 	kfree(msg);
419 }
420 
sk_psock_report_error(struct sk_psock * psock,int err)421 static inline void sk_psock_report_error(struct sk_psock *psock, int err)
422 {
423 	struct sock *sk = psock->sk;
424 
425 	sk->sk_err = err;
426 	sk_error_report(sk);
427 }
428 
429 struct sk_psock *sk_psock_init(struct sock *sk, int node);
430 void sk_psock_stop(struct sk_psock *psock);
431 
432 #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
433 int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock);
434 void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock);
435 void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock);
436 #else
sk_psock_init_strp(struct sock * sk,struct sk_psock * psock)437 static inline int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
438 {
439 	return -EOPNOTSUPP;
440 }
441 
sk_psock_start_strp(struct sock * sk,struct sk_psock * psock)442 static inline void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
443 {
444 }
445 
sk_psock_stop_strp(struct sock * sk,struct sk_psock * psock)446 static inline void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
447 {
448 }
449 #endif
450 
451 void sk_psock_start_verdict(struct sock *sk, struct sk_psock *psock);
452 void sk_psock_stop_verdict(struct sock *sk, struct sk_psock *psock);
453 
454 int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
455 			 struct sk_msg *msg);
456 
457 /*
458  * This specialized allocator has to be a macro for its allocations to be
459  * accounted separately (to have a separate alloc_tag). The typecast is
460  * intentional to enforce typesafety.
461  */
462 #define sk_psock_init_link()	\
463 		kzalloc_obj(struct sk_psock_link, GFP_ATOMIC | __GFP_NOWARN)
464 
sk_psock_free_link(struct sk_psock_link * link)465 static inline void sk_psock_free_link(struct sk_psock_link *link)
466 {
467 	kfree(link);
468 }
469 
470 struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock);
471 
sk_psock_cork_free(struct sk_psock * psock)472 static inline void sk_psock_cork_free(struct sk_psock *psock)
473 {
474 	if (psock->cork) {
475 		sk_msg_free(psock->sk, psock->cork);
476 		kfree(psock->cork);
477 		psock->cork = NULL;
478 	}
479 }
480 
sk_psock_restore_proto(struct sock * sk,struct sk_psock * psock)481 static inline void sk_psock_restore_proto(struct sock *sk,
482 					  struct sk_psock *psock)
483 {
484 	if (psock->psock_update_sk_prot)
485 		psock->psock_update_sk_prot(sk, psock, true);
486 }
487 
sk_psock_get(struct sock * sk)488 static inline struct sk_psock *sk_psock_get(struct sock *sk)
489 {
490 	struct sk_psock *psock;
491 
492 	rcu_read_lock();
493 	psock = sk_psock(sk);
494 	if (psock && !refcount_inc_not_zero(&psock->refcnt))
495 		psock = NULL;
496 	rcu_read_unlock();
497 	return psock;
498 }
499 
500 void sk_psock_drop(struct sock *sk, struct sk_psock *psock);
501 
sk_psock_put(struct sock * sk,struct sk_psock * psock)502 static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
503 {
504 	if (refcount_dec_and_test(&psock->refcnt))
505 		sk_psock_drop(sk, psock);
506 }
507 
sk_psock_data_ready(struct sock * sk,struct sk_psock * psock)508 static inline void sk_psock_data_ready(struct sock *sk, struct sk_psock *psock)
509 {
510 	read_lock_bh(&sk->sk_callback_lock);
511 	if (psock->saved_data_ready)
512 		psock->saved_data_ready(sk);
513 	else
514 		sk->sk_data_ready(sk);
515 	read_unlock_bh(&sk->sk_callback_lock);
516 }
517 
psock_set_prog(struct bpf_prog ** pprog,struct bpf_prog * prog)518 static inline void psock_set_prog(struct bpf_prog **pprog,
519 				  struct bpf_prog *prog)
520 {
521 	prog = xchg(pprog, prog);
522 	if (prog)
523 		bpf_prog_put(prog);
524 }
525 
psock_replace_prog(struct bpf_prog ** pprog,struct bpf_prog * prog,struct bpf_prog * old)526 static inline int psock_replace_prog(struct bpf_prog **pprog,
527 				     struct bpf_prog *prog,
528 				     struct bpf_prog *old)
529 {
530 	if (cmpxchg(pprog, old, prog) != old)
531 		return -ENOENT;
532 
533 	if (old)
534 		bpf_prog_put(old);
535 
536 	return 0;
537 }
538 
psock_progs_drop(struct sk_psock_progs * progs)539 static inline void psock_progs_drop(struct sk_psock_progs *progs)
540 {
541 	psock_set_prog(&progs->msg_parser, NULL);
542 	psock_set_prog(&progs->stream_parser, NULL);
543 	psock_set_prog(&progs->stream_verdict, NULL);
544 	psock_set_prog(&progs->skb_verdict, NULL);
545 }
546 
547 int sk_psock_tls_strp_read(struct sk_psock *psock, struct sk_buff *skb);
548 
sk_psock_strp_enabled(struct sk_psock * psock)549 static inline bool sk_psock_strp_enabled(struct sk_psock *psock)
550 {
551 	if (!psock)
552 		return false;
553 	return !!psock->saved_data_ready;
554 }
555 
556 /* for tcp only, sk is locked */
sk_psock_msg_inq(struct sock * sk)557 static inline ssize_t sk_psock_msg_inq(struct sock *sk)
558 {
559 	struct sk_psock *psock;
560 	ssize_t inq = 0;
561 
562 	psock = sk_psock_get(sk);
563 	if (likely(psock)) {
564 		inq = sk_psock_get_msg_len_nolock(psock);
565 		sk_psock_put(sk, psock);
566 	}
567 	return inq;
568 }
569 
570 /* for udp only, sk is not locked */
sk_msg_first_len(struct sock * sk)571 static inline ssize_t sk_msg_first_len(struct sock *sk)
572 {
573 	struct sk_psock *psock;
574 	struct sk_msg *msg;
575 	ssize_t inq = 0;
576 
577 	psock = sk_psock_get(sk);
578 	if (likely(psock)) {
579 		spin_lock_bh(&psock->ingress_lock);
580 		msg = sk_psock_peek_msg_locked(psock);
581 		if (msg)
582 			inq = msg->sg.size;
583 		spin_unlock_bh(&psock->ingress_lock);
584 		sk_psock_put(sk, psock);
585 	}
586 	return inq;
587 }
588 
589 #if IS_ENABLED(CONFIG_NET_SOCK_MSG)
590 
591 #define BPF_F_STRPARSER	(1UL << 1)
592 
593 /* We only have two bits so far. */
594 #define BPF_F_PTR_MASK ~(BPF_F_INGRESS | BPF_F_STRPARSER)
595 
skb_bpf_strparser(const struct sk_buff * skb)596 static inline bool skb_bpf_strparser(const struct sk_buff *skb)
597 {
598 	unsigned long sk_redir = skb->_sk_redir;
599 
600 	return sk_redir & BPF_F_STRPARSER;
601 }
602 
skb_bpf_set_strparser(struct sk_buff * skb)603 static inline void skb_bpf_set_strparser(struct sk_buff *skb)
604 {
605 	skb->_sk_redir |= BPF_F_STRPARSER;
606 }
607 
skb_bpf_ingress(const struct sk_buff * skb)608 static inline bool skb_bpf_ingress(const struct sk_buff *skb)
609 {
610 	unsigned long sk_redir = skb->_sk_redir;
611 
612 	return sk_redir & BPF_F_INGRESS;
613 }
614 
skb_bpf_set_ingress(struct sk_buff * skb)615 static inline void skb_bpf_set_ingress(struct sk_buff *skb)
616 {
617 	skb->_sk_redir |= BPF_F_INGRESS;
618 }
619 
skb_bpf_set_redir(struct sk_buff * skb,struct sock * sk_redir,bool ingress)620 static inline void skb_bpf_set_redir(struct sk_buff *skb, struct sock *sk_redir,
621 				     bool ingress)
622 {
623 	skb->_sk_redir = (unsigned long)sk_redir;
624 	if (ingress)
625 		skb->_sk_redir |= BPF_F_INGRESS;
626 }
627 
skb_bpf_redirect_fetch(const struct sk_buff * skb)628 static inline struct sock *skb_bpf_redirect_fetch(const struct sk_buff *skb)
629 {
630 	unsigned long sk_redir = skb->_sk_redir;
631 
632 	return (struct sock *)(sk_redir & BPF_F_PTR_MASK);
633 }
634 
skb_bpf_redirect_clear(struct sk_buff * skb)635 static inline void skb_bpf_redirect_clear(struct sk_buff *skb)
636 {
637 	skb->_sk_redir = 0;
638 }
639 #endif /* CONFIG_NET_SOCK_MSG */
640 #endif /* _LINUX_SKMSG_H */
641