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Commit | Line | Data |
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17926a79 DH |
1 | /* RxRPC recvmsg() implementation |
2 | * | |
3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
9b6d5398 JP |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | ||
17926a79 DH |
14 | #include <linux/net.h> |
15 | #include <linux/skbuff.h> | |
bc3b2d7f | 16 | #include <linux/export.h> |
17926a79 DH |
17 | #include <net/sock.h> |
18 | #include <net/af_rxrpc.h> | |
19 | #include "ar-internal.h" | |
20 | ||
17926a79 | 21 | /* |
248f219c DH |
22 | * Post a call for attention by the socket or kernel service. Further |
23 | * notifications are suppressed by putting recvmsg_link on a dummy queue. | |
17926a79 | 24 | */ |
248f219c | 25 | void rxrpc_notify_socket(struct rxrpc_call *call) |
17926a79 | 26 | { |
248f219c DH |
27 | struct rxrpc_sock *rx; |
28 | struct sock *sk; | |
17926a79 | 29 | |
248f219c | 30 | _enter("%d", call->debug_id); |
17926a79 | 31 | |
248f219c DH |
32 | if (!list_empty(&call->recvmsg_link)) |
33 | return; | |
34 | ||
35 | rcu_read_lock(); | |
36 | ||
37 | rx = rcu_dereference(call->socket); | |
38 | sk = &rx->sk; | |
39 | if (rx && sk->sk_state < RXRPC_CLOSE) { | |
40 | if (call->notify_rx) { | |
41 | call->notify_rx(sk, call, call->user_call_ID); | |
42 | } else { | |
43 | write_lock_bh(&rx->recvmsg_lock); | |
44 | if (list_empty(&call->recvmsg_link)) { | |
45 | rxrpc_get_call(call, rxrpc_call_got); | |
46 | list_add_tail(&call->recvmsg_link, &rx->recvmsg_q); | |
47 | } | |
48 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 49 | |
248f219c DH |
50 | if (!sock_flag(sk, SOCK_DEAD)) { |
51 | _debug("call %ps", sk->sk_data_ready); | |
52 | sk->sk_data_ready(sk); | |
53 | } | |
54 | } | |
55 | } | |
17926a79 | 56 | |
248f219c DH |
57 | rcu_read_unlock(); |
58 | _leave(""); | |
59 | } | |
17926a79 | 60 | |
248f219c DH |
61 | /* |
62 | * Pass a call terminating message to userspace. | |
63 | */ | |
64 | static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg) | |
65 | { | |
66 | u32 tmp = 0; | |
67 | int ret; | |
17926a79 | 68 | |
248f219c DH |
69 | switch (call->completion) { |
70 | case RXRPC_CALL_SUCCEEDED: | |
71 | ret = 0; | |
72 | if (rxrpc_is_service_call(call)) | |
73 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &tmp); | |
74 | break; | |
75 | case RXRPC_CALL_REMOTELY_ABORTED: | |
76 | tmp = call->abort_code; | |
77 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
78 | break; | |
79 | case RXRPC_CALL_LOCALLY_ABORTED: | |
80 | tmp = call->abort_code; | |
81 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); | |
82 | break; | |
83 | case RXRPC_CALL_NETWORK_ERROR: | |
84 | tmp = call->error; | |
85 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &tmp); | |
86 | break; | |
87 | case RXRPC_CALL_LOCAL_ERROR: | |
88 | tmp = call->error; | |
89 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4, &tmp); | |
90 | break; | |
91 | default: | |
92 | pr_err("Invalid terminal call state %u\n", call->state); | |
93 | BUG(); | |
94 | break; | |
95 | } | |
17926a79 | 96 | |
84997905 DH |
97 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_terminal, call->rx_hard_ack, |
98 | call->rx_pkt_offset, call->rx_pkt_len, ret); | |
248f219c DH |
99 | return ret; |
100 | } | |
17926a79 | 101 | |
248f219c DH |
102 | /* |
103 | * Pass back notification of a new call. The call is added to the | |
104 | * to-be-accepted list. This means that the next call to be accepted might not | |
105 | * be the last call seen awaiting acceptance, but unless we leave this on the | |
106 | * front of the queue and block all other messages until someone gives us a | |
107 | * user_ID for it, there's not a lot we can do. | |
108 | */ | |
109 | static int rxrpc_recvmsg_new_call(struct rxrpc_sock *rx, | |
110 | struct rxrpc_call *call, | |
111 | struct msghdr *msg, int flags) | |
112 | { | |
113 | int tmp = 0, ret; | |
17926a79 | 114 | |
248f219c | 115 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &tmp); |
17926a79 | 116 | |
248f219c DH |
117 | if (ret == 0 && !(flags & MSG_PEEK)) { |
118 | _debug("to be accepted"); | |
119 | write_lock_bh(&rx->recvmsg_lock); | |
120 | list_del_init(&call->recvmsg_link); | |
121 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 122 | |
3432a757 | 123 | rxrpc_get_call(call, rxrpc_call_got); |
248f219c DH |
124 | write_lock(&rx->call_lock); |
125 | list_add_tail(&call->accept_link, &rx->to_be_accepted); | |
126 | write_unlock(&rx->call_lock); | |
127 | } | |
17926a79 | 128 | |
84997905 | 129 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_to_be_accepted, 1, 0, 0, ret); |
248f219c DH |
130 | return ret; |
131 | } | |
17926a79 | 132 | |
248f219c DH |
133 | /* |
134 | * End the packet reception phase. | |
135 | */ | |
b69d94d7 | 136 | static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) |
248f219c DH |
137 | { |
138 | _enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]); | |
17926a79 | 139 | |
58dc63c9 | 140 | trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); |
816c9fce DH |
141 | ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); |
142 | ||
248f219c | 143 | if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { |
b69d94d7 | 144 | rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false, |
9c7ad434 | 145 | rxrpc_propose_ack_terminal_ack); |
a5af7e1f | 146 | rxrpc_send_ack_packet(call, false); |
248f219c | 147 | } |
17926a79 | 148 | |
248f219c | 149 | write_lock_bh(&call->state_lock); |
17926a79 | 150 | |
248f219c DH |
151 | switch (call->state) { |
152 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
153 | __rxrpc_call_completed(call); | |
9749fd2b | 154 | write_unlock_bh(&call->state_lock); |
248f219c | 155 | break; |
17926a79 | 156 | |
248f219c | 157 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
71f3ca40 | 158 | call->tx_phase = true; |
248f219c | 159 | call->state = RXRPC_CALL_SERVER_ACK_REQUEST; |
9749fd2b DH |
160 | call->ack_at = call->expire_at; |
161 | write_unlock_bh(&call->state_lock); | |
162 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true, | |
163 | rxrpc_propose_ack_processing_op); | |
248f219c DH |
164 | break; |
165 | default: | |
9749fd2b | 166 | write_unlock_bh(&call->state_lock); |
248f219c DH |
167 | break; |
168 | } | |
248f219c | 169 | } |
17926a79 | 170 | |
248f219c DH |
171 | /* |
172 | * Discard a packet we've used up and advance the Rx window by one. | |
173 | */ | |
174 | static void rxrpc_rotate_rx_window(struct rxrpc_call *call) | |
175 | { | |
816c9fce | 176 | struct rxrpc_skb_priv *sp; |
248f219c | 177 | struct sk_buff *skb; |
58dc63c9 | 178 | rxrpc_serial_t serial; |
248f219c | 179 | rxrpc_seq_t hard_ack, top; |
816c9fce | 180 | u8 flags; |
248f219c DH |
181 | int ix; |
182 | ||
183 | _enter("%d", call->debug_id); | |
184 | ||
185 | hard_ack = call->rx_hard_ack; | |
186 | top = smp_load_acquire(&call->rx_top); | |
187 | ASSERT(before(hard_ack, top)); | |
188 | ||
189 | hard_ack++; | |
190 | ix = hard_ack & RXRPC_RXTX_BUFF_MASK; | |
191 | skb = call->rxtx_buffer[ix]; | |
71f3ca40 | 192 | rxrpc_see_skb(skb, rxrpc_skb_rx_rotated); |
816c9fce DH |
193 | sp = rxrpc_skb(skb); |
194 | flags = sp->hdr.flags; | |
58dc63c9 DH |
195 | serial = sp->hdr.serial; |
196 | if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) | |
197 | serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1; | |
198 | ||
248f219c DH |
199 | call->rxtx_buffer[ix] = NULL; |
200 | call->rxtx_annotations[ix] = 0; | |
201 | /* Barrier against rxrpc_input_data(). */ | |
202 | smp_store_release(&call->rx_hard_ack, hard_ack); | |
17926a79 | 203 | |
71f3ca40 | 204 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
17926a79 | 205 | |
816c9fce | 206 | _debug("%u,%u,%02x", hard_ack, top, flags); |
58dc63c9 | 207 | trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); |
805b21b9 | 208 | if (flags & RXRPC_LAST_PACKET) { |
b69d94d7 | 209 | rxrpc_end_rx_phase(call, serial); |
805b21b9 DH |
210 | } else { |
211 | /* Check to see if there's an ACK that needs sending. */ | |
212 | if (after_eq(hard_ack, call->ackr_consumed + 2) || | |
213 | after_eq(top, call->ackr_seen + 2) || | |
214 | (hard_ack == top && after(hard_ack, call->ackr_consumed))) | |
215 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, | |
216 | true, false, | |
217 | rxrpc_propose_ack_rotate_rx); | |
218 | if (call->ackr_reason) | |
a5af7e1f | 219 | rxrpc_send_ack_packet(call, false); |
805b21b9 | 220 | } |
248f219c DH |
221 | } |
222 | ||
223 | /* | |
224 | * Decrypt and verify a (sub)packet. The packet's length may be changed due to | |
225 | * padding, but if this is the case, the packet length will be resident in the | |
226 | * socket buffer. Note that we can't modify the master skb info as the skb may | |
227 | * be the home to multiple subpackets. | |
228 | */ | |
229 | static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb, | |
230 | u8 annotation, | |
231 | unsigned int offset, unsigned int len) | |
232 | { | |
233 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); | |
234 | rxrpc_seq_t seq = sp->hdr.seq; | |
235 | u16 cksum = sp->hdr.cksum; | |
236 | ||
237 | _enter(""); | |
238 | ||
239 | /* For all but the head jumbo subpacket, the security checksum is in a | |
240 | * jumbo header immediately prior to the data. | |
241 | */ | |
242 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) { | |
243 | __be16 tmp; | |
244 | if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0) | |
245 | BUG(); | |
246 | cksum = ntohs(tmp); | |
247 | seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1; | |
248 | } | |
249 | ||
250 | return call->conn->security->verify_packet(call, skb, offset, len, | |
251 | seq, cksum); | |
252 | } | |
253 | ||
254 | /* | |
255 | * Locate the data within a packet. This is complicated by: | |
256 | * | |
257 | * (1) An skb may contain a jumbo packet - so we have to find the appropriate | |
258 | * subpacket. | |
259 | * | |
260 | * (2) The (sub)packets may be encrypted and, if so, the encrypted portion | |
261 | * contains an extra header which includes the true length of the data, | |
262 | * excluding any encrypted padding. | |
263 | */ | |
264 | static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb, | |
265 | u8 *_annotation, | |
266 | unsigned int *_offset, unsigned int *_len) | |
267 | { | |
775e5b71 | 268 | unsigned int offset = sizeof(struct rxrpc_wire_header); |
248f219c DH |
269 | unsigned int len = *_len; |
270 | int ret; | |
271 | u8 annotation = *_annotation; | |
272 | ||
248f219c | 273 | /* Locate the subpacket */ |
775e5b71 | 274 | len = skb->len - offset; |
248f219c DH |
275 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) { |
276 | offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) * | |
277 | RXRPC_JUMBO_SUBPKTLEN); | |
278 | len = (annotation & RXRPC_RX_ANNO_JLAST) ? | |
279 | skb->len - offset : RXRPC_JUMBO_SUBPKTLEN; | |
280 | } | |
281 | ||
282 | if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) { | |
283 | ret = rxrpc_verify_packet(call, skb, annotation, offset, len); | |
17926a79 | 284 | if (ret < 0) |
248f219c DH |
285 | return ret; |
286 | *_annotation |= RXRPC_RX_ANNO_VERIFIED; | |
287 | } | |
17926a79 | 288 | |
248f219c DH |
289 | *_offset = offset; |
290 | *_len = len; | |
291 | call->conn->security->locate_data(call, skb, _offset, _len); | |
292 | return 0; | |
293 | } | |
17926a79 | 294 | |
248f219c DH |
295 | /* |
296 | * Deliver messages to a call. This keeps processing packets until the buffer | |
297 | * is filled and we find either more DATA (returns 0) or the end of the DATA | |
298 | * (returns 1). If more packets are required, it returns -EAGAIN. | |
299 | */ | |
300 | static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call, | |
301 | struct msghdr *msg, struct iov_iter *iter, | |
302 | size_t len, int flags, size_t *_offset) | |
303 | { | |
304 | struct rxrpc_skb_priv *sp; | |
305 | struct sk_buff *skb; | |
306 | rxrpc_seq_t hard_ack, top, seq; | |
307 | size_t remain; | |
308 | bool last; | |
309 | unsigned int rx_pkt_offset, rx_pkt_len; | |
816c9fce | 310 | int ix, copy, ret = -EAGAIN, ret2; |
248f219c | 311 | |
248f219c DH |
312 | rx_pkt_offset = call->rx_pkt_offset; |
313 | rx_pkt_len = call->rx_pkt_len; | |
314 | ||
816c9fce DH |
315 | if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) { |
316 | seq = call->rx_hard_ack; | |
317 | ret = 1; | |
318 | goto done; | |
319 | } | |
320 | ||
248f219c DH |
321 | /* Barriers against rxrpc_input_data(). */ |
322 | hard_ack = call->rx_hard_ack; | |
d7e15835 DH |
323 | seq = hard_ack + 1; |
324 | while (top = smp_load_acquire(&call->rx_top), | |
325 | before_eq(seq, top) | |
326 | ) { | |
248f219c DH |
327 | ix = seq & RXRPC_RXTX_BUFF_MASK; |
328 | skb = call->rxtx_buffer[ix]; | |
84997905 DH |
329 | if (!skb) { |
330 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq, | |
331 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 332 | break; |
84997905 | 333 | } |
248f219c | 334 | smp_rmb(); |
71f3ca40 | 335 | rxrpc_see_skb(skb, rxrpc_skb_rx_seen); |
248f219c | 336 | sp = rxrpc_skb(skb); |
17926a79 | 337 | |
58dc63c9 DH |
338 | if (!(flags & MSG_PEEK)) |
339 | trace_rxrpc_receive(call, rxrpc_receive_front, | |
340 | sp->hdr.serial, seq); | |
341 | ||
248f219c DH |
342 | if (msg) |
343 | sock_recv_timestamp(msg, sock->sk, skb); | |
344 | ||
2e2ea51d | 345 | if (rx_pkt_offset == 0) { |
816c9fce DH |
346 | ret2 = rxrpc_locate_data(call, skb, |
347 | &call->rxtx_annotations[ix], | |
348 | &rx_pkt_offset, &rx_pkt_len); | |
84997905 DH |
349 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq, |
350 | rx_pkt_offset, rx_pkt_len, ret2); | |
816c9fce DH |
351 | if (ret2 < 0) { |
352 | ret = ret2; | |
2e2ea51d | 353 | goto out; |
816c9fce | 354 | } |
84997905 DH |
355 | } else { |
356 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq, | |
357 | rx_pkt_offset, rx_pkt_len, 0); | |
2e2ea51d | 358 | } |
248f219c DH |
359 | |
360 | /* We have to handle short, empty and used-up DATA packets. */ | |
361 | remain = len - *_offset; | |
362 | copy = rx_pkt_len; | |
363 | if (copy > remain) | |
364 | copy = remain; | |
365 | if (copy > 0) { | |
816c9fce DH |
366 | ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter, |
367 | copy); | |
368 | if (ret2 < 0) { | |
369 | ret = ret2; | |
248f219c | 370 | goto out; |
816c9fce | 371 | } |
248f219c DH |
372 | |
373 | /* handle piecemeal consumption of data packets */ | |
248f219c DH |
374 | rx_pkt_offset += copy; |
375 | rx_pkt_len -= copy; | |
376 | *_offset += copy; | |
377 | } | |
17926a79 | 378 | |
248f219c | 379 | if (rx_pkt_len > 0) { |
84997905 DH |
380 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq, |
381 | rx_pkt_offset, rx_pkt_len, 0); | |
248f219c | 382 | ASSERTCMP(*_offset, ==, len); |
816c9fce | 383 | ret = 0; |
17926a79 DH |
384 | break; |
385 | } | |
386 | ||
248f219c DH |
387 | /* The whole packet has been transferred. */ |
388 | last = sp->hdr.flags & RXRPC_LAST_PACKET; | |
372ee163 | 389 | if (!(flags & MSG_PEEK)) |
248f219c DH |
390 | rxrpc_rotate_rx_window(call); |
391 | rx_pkt_offset = 0; | |
392 | rx_pkt_len = 0; | |
17926a79 | 393 | |
816c9fce DH |
394 | if (last) { |
395 | ASSERTCMP(seq, ==, READ_ONCE(call->rx_top)); | |
248f219c | 396 | ret = 1; |
816c9fce DH |
397 | goto out; |
398 | } | |
d7e15835 DH |
399 | |
400 | seq++; | |
248f219c | 401 | } |
816c9fce | 402 | |
248f219c DH |
403 | out: |
404 | if (!(flags & MSG_PEEK)) { | |
405 | call->rx_pkt_offset = rx_pkt_offset; | |
406 | call->rx_pkt_len = rx_pkt_len; | |
407 | } | |
816c9fce | 408 | done: |
84997905 DH |
409 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq, |
410 | rx_pkt_offset, rx_pkt_len, ret); | |
248f219c DH |
411 | return ret; |
412 | } | |
17926a79 | 413 | |
248f219c DH |
414 | /* |
415 | * Receive a message from an RxRPC socket | |
416 | * - we need to be careful about two or more threads calling recvmsg | |
417 | * simultaneously | |
418 | */ | |
419 | int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, | |
420 | int flags) | |
421 | { | |
422 | struct rxrpc_call *call; | |
423 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); | |
424 | struct list_head *l; | |
425 | size_t copied = 0; | |
426 | long timeo; | |
427 | int ret; | |
428 | ||
429 | DEFINE_WAIT(wait); | |
430 | ||
84997905 | 431 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0); |
248f219c DH |
432 | |
433 | if (flags & (MSG_OOB | MSG_TRUNC)) | |
434 | return -EOPNOTSUPP; | |
435 | ||
436 | timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); | |
437 | ||
438 | try_again: | |
439 | lock_sock(&rx->sk); | |
440 | ||
441 | /* Return immediately if a client socket has no outstanding calls */ | |
442 | if (RB_EMPTY_ROOT(&rx->calls) && | |
443 | list_empty(&rx->recvmsg_q) && | |
444 | rx->sk.sk_state != RXRPC_SERVER_LISTENING) { | |
445 | release_sock(&rx->sk); | |
446 | return -ENODATA; | |
17926a79 DH |
447 | } |
448 | ||
248f219c DH |
449 | if (list_empty(&rx->recvmsg_q)) { |
450 | ret = -EWOULDBLOCK; | |
84997905 DH |
451 | if (timeo == 0) { |
452 | call = NULL; | |
248f219c | 453 | goto error_no_call; |
84997905 | 454 | } |
248f219c DH |
455 | |
456 | release_sock(&rx->sk); | |
457 | ||
458 | /* Wait for something to happen */ | |
459 | prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, | |
460 | TASK_INTERRUPTIBLE); | |
461 | ret = sock_error(&rx->sk); | |
462 | if (ret) | |
463 | goto wait_error; | |
464 | ||
465 | if (list_empty(&rx->recvmsg_q)) { | |
466 | if (signal_pending(current)) | |
467 | goto wait_interrupted; | |
84997905 DH |
468 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, |
469 | 0, 0, 0, 0); | |
248f219c | 470 | timeo = schedule_timeout(timeo); |
17926a79 | 471 | } |
248f219c DH |
472 | finish_wait(sk_sleep(&rx->sk), &wait); |
473 | goto try_again; | |
17926a79 DH |
474 | } |
475 | ||
248f219c DH |
476 | /* Find the next call and dequeue it if we're not just peeking. If we |
477 | * do dequeue it, that comes with a ref that we will need to release. | |
478 | */ | |
479 | write_lock_bh(&rx->recvmsg_lock); | |
480 | l = rx->recvmsg_q.next; | |
481 | call = list_entry(l, struct rxrpc_call, recvmsg_link); | |
482 | if (!(flags & MSG_PEEK)) | |
483 | list_del_init(&call->recvmsg_link); | |
484 | else | |
485 | rxrpc_get_call(call, rxrpc_call_got); | |
486 | write_unlock_bh(&rx->recvmsg_lock); | |
17926a79 | 487 | |
84997905 | 488 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0); |
248f219c DH |
489 | |
490 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) | |
17926a79 | 491 | BUG(); |
248f219c DH |
492 | |
493 | if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { | |
494 | if (flags & MSG_CMSG_COMPAT) { | |
495 | unsigned int id32 = call->user_call_ID; | |
496 | ||
497 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
498 | sizeof(unsigned int), &id32); | |
499 | } else { | |
500 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, | |
501 | sizeof(unsigned long), | |
502 | &call->user_call_ID); | |
f5c17aae | 503 | } |
248f219c DH |
504 | if (ret < 0) |
505 | goto error; | |
506 | } | |
507 | ||
508 | if (msg->msg_name) { | |
509 | size_t len = sizeof(call->conn->params.peer->srx); | |
510 | memcpy(msg->msg_name, &call->conn->params.peer->srx, len); | |
511 | msg->msg_namelen = len; | |
512 | } | |
513 | ||
514 | switch (call->state) { | |
515 | case RXRPC_CALL_SERVER_ACCEPTING: | |
516 | ret = rxrpc_recvmsg_new_call(rx, call, msg, flags); | |
17926a79 | 517 | break; |
248f219c DH |
518 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
519 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
520 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
521 | ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len, | |
522 | flags, &copied); | |
523 | if (ret == -EAGAIN) | |
524 | ret = 0; | |
33b603fd DH |
525 | |
526 | if (after(call->rx_top, call->rx_hard_ack) && | |
527 | call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK]) | |
528 | rxrpc_notify_socket(call); | |
17926a79 DH |
529 | break; |
530 | default: | |
248f219c | 531 | ret = 0; |
17926a79 DH |
532 | break; |
533 | } | |
534 | ||
535 | if (ret < 0) | |
248f219c | 536 | goto error; |
17926a79 | 537 | |
248f219c DH |
538 | if (call->state == RXRPC_CALL_COMPLETE) { |
539 | ret = rxrpc_recvmsg_term(call, msg); | |
540 | if (ret < 0) | |
541 | goto error; | |
542 | if (!(flags & MSG_PEEK)) | |
543 | rxrpc_release_call(rx, call); | |
544 | msg->msg_flags |= MSG_EOR; | |
545 | ret = 1; | |
17926a79 DH |
546 | } |
547 | ||
248f219c DH |
548 | if (ret == 0) |
549 | msg->msg_flags |= MSG_MORE; | |
550 | else | |
551 | msg->msg_flags &= ~MSG_MORE; | |
552 | ret = copied; | |
17926a79 | 553 | |
248f219c | 554 | error: |
fff72429 | 555 | rxrpc_put_call(call, rxrpc_call_put); |
248f219c DH |
556 | error_no_call: |
557 | release_sock(&rx->sk); | |
84997905 | 558 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
17926a79 DH |
559 | return ret; |
560 | ||
17926a79 DH |
561 | wait_interrupted: |
562 | ret = sock_intr_errno(timeo); | |
563 | wait_error: | |
4a4771a5 | 564 | finish_wait(sk_sleep(&rx->sk), &wait); |
84997905 DH |
565 | call = NULL; |
566 | goto error_no_call; | |
d001648e | 567 | } |
651350d1 DH |
568 | |
569 | /** | |
d001648e DH |
570 | * rxrpc_kernel_recv_data - Allow a kernel service to receive data/info |
571 | * @sock: The socket that the call exists on | |
572 | * @call: The call to send data through | |
573 | * @buf: The buffer to receive into | |
574 | * @size: The size of the buffer, including data already read | |
575 | * @_offset: The running offset into the buffer. | |
576 | * @want_more: True if more data is expected to be read | |
577 | * @_abort: Where the abort code is stored if -ECONNABORTED is returned | |
578 | * | |
579 | * Allow a kernel service to receive data and pick up information about the | |
580 | * state of a call. Returns 0 if got what was asked for and there's more | |
581 | * available, 1 if we got what was asked for and we're at the end of the data | |
582 | * and -EAGAIN if we need more data. | |
583 | * | |
584 | * Note that we may return -EAGAIN to drain empty packets at the end of the | |
585 | * data, even if we've already copied over the requested data. | |
651350d1 | 586 | * |
d001648e DH |
587 | * This function adds the amount it transfers to *_offset, so this should be |
588 | * precleared as appropriate. Note that the amount remaining in the buffer is | |
589 | * taken to be size - *_offset. | |
590 | * | |
591 | * *_abort should also be initialised to 0. | |
651350d1 | 592 | */ |
d001648e DH |
593 | int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call, |
594 | void *buf, size_t size, size_t *_offset, | |
595 | bool want_more, u32 *_abort) | |
651350d1 | 596 | { |
d001648e DH |
597 | struct iov_iter iter; |
598 | struct kvec iov; | |
599 | int ret; | |
651350d1 | 600 | |
248f219c DH |
601 | _enter("{%d,%s},%zu/%zu,%d", |
602 | call->debug_id, rxrpc_call_states[call->state], | |
603 | *_offset, size, want_more); | |
d001648e DH |
604 | |
605 | ASSERTCMP(*_offset, <=, size); | |
606 | ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING); | |
651350d1 | 607 | |
d001648e DH |
608 | iov.iov_base = buf + *_offset; |
609 | iov.iov_len = size - *_offset; | |
610 | iov_iter_kvec(&iter, ITER_KVEC | READ, &iov, 1, size - *_offset); | |
611 | ||
612 | lock_sock(sock->sk); | |
613 | ||
614 | switch (call->state) { | |
615 | case RXRPC_CALL_CLIENT_RECV_REPLY: | |
616 | case RXRPC_CALL_SERVER_RECV_REQUEST: | |
617 | case RXRPC_CALL_SERVER_ACK_REQUEST: | |
248f219c DH |
618 | ret = rxrpc_recvmsg_data(sock, call, NULL, &iter, size, 0, |
619 | _offset); | |
d001648e DH |
620 | if (ret < 0) |
621 | goto out; | |
622 | ||
623 | /* We can only reach here with a partially full buffer if we | |
624 | * have reached the end of the data. We must otherwise have a | |
625 | * full buffer or have been given -EAGAIN. | |
626 | */ | |
627 | if (ret == 1) { | |
628 | if (*_offset < size) | |
629 | goto short_data; | |
630 | if (!want_more) | |
631 | goto read_phase_complete; | |
632 | ret = 0; | |
633 | goto out; | |
634 | } | |
635 | ||
636 | if (!want_more) | |
637 | goto excess_data; | |
638 | goto out; | |
639 | ||
640 | case RXRPC_CALL_COMPLETE: | |
641 | goto call_complete; | |
642 | ||
643 | default: | |
d001648e DH |
644 | ret = -EINPROGRESS; |
645 | goto out; | |
646 | } | |
647 | ||
648 | read_phase_complete: | |
649 | ret = 1; | |
650 | out: | |
651 | release_sock(sock->sk); | |
652 | _leave(" = %d [%zu,%d]", ret, *_offset, *_abort); | |
653 | return ret; | |
654 | ||
655 | short_data: | |
656 | ret = -EBADMSG; | |
657 | goto out; | |
658 | excess_data: | |
659 | ret = -EMSGSIZE; | |
660 | goto out; | |
661 | call_complete: | |
662 | *_abort = call->abort_code; | |
cf69207a | 663 | ret = -call->error; |
d001648e DH |
664 | if (call->completion == RXRPC_CALL_SUCCEEDED) { |
665 | ret = 1; | |
666 | if (size > 0) | |
667 | ret = -ECONNRESET; | |
668 | } | |
669 | goto out; | |
670 | } | |
671 | EXPORT_SYMBOL(rxrpc_kernel_recv_data); |