Commit | Line | Data |
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17926a79 DH |
1 | /* incoming call handling |
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/module.h> |
15 | #include <linux/net.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/errqueue.h> | |
18 | #include <linux/udp.h> | |
19 | #include <linux/in.h> | |
20 | #include <linux/in6.h> | |
21 | #include <linux/icmp.h> | |
5a0e3ad6 | 22 | #include <linux/gfp.h> |
00e90712 | 23 | #include <linux/circ_buf.h> |
17926a79 DH |
24 | #include <net/sock.h> |
25 | #include <net/af_rxrpc.h> | |
26 | #include <net/ip.h> | |
27 | #include "ar-internal.h" | |
28 | ||
00e90712 DH |
29 | /* |
30 | * Preallocate a single service call, connection and peer and, if possible, | |
31 | * give them a user ID and attach the user's side of the ID to them. | |
32 | */ | |
33 | static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx, | |
34 | struct rxrpc_backlog *b, | |
35 | rxrpc_notify_rx_t notify_rx, | |
36 | rxrpc_user_attach_call_t user_attach_call, | |
37 | unsigned long user_call_ID, gfp_t gfp) | |
38 | { | |
39 | const void *here = __builtin_return_address(0); | |
40 | struct rxrpc_call *call; | |
41 | int max, tmp; | |
42 | unsigned int size = RXRPC_BACKLOG_MAX; | |
43 | unsigned int head, tail, call_head, call_tail; | |
44 | ||
45 | max = rx->sk.sk_max_ack_backlog; | |
46 | tmp = rx->sk.sk_ack_backlog; | |
47 | if (tmp >= max) { | |
48 | _leave(" = -ENOBUFS [full %u]", max); | |
49 | return -ENOBUFS; | |
50 | } | |
51 | max -= tmp; | |
52 | ||
53 | /* We don't need more conns and peers than we have calls, but on the | |
54 | * other hand, we shouldn't ever use more peers than conns or conns | |
55 | * than calls. | |
56 | */ | |
57 | call_head = b->call_backlog_head; | |
58 | call_tail = READ_ONCE(b->call_backlog_tail); | |
59 | tmp = CIRC_CNT(call_head, call_tail, size); | |
60 | if (tmp >= max) { | |
61 | _leave(" = -ENOBUFS [enough %u]", tmp); | |
62 | return -ENOBUFS; | |
63 | } | |
64 | max = tmp + 1; | |
65 | ||
66 | head = b->peer_backlog_head; | |
67 | tail = READ_ONCE(b->peer_backlog_tail); | |
68 | if (CIRC_CNT(head, tail, size) < max) { | |
69 | struct rxrpc_peer *peer = rxrpc_alloc_peer(rx->local, gfp); | |
70 | if (!peer) | |
71 | return -ENOMEM; | |
72 | b->peer_backlog[head] = peer; | |
73 | smp_store_release(&b->peer_backlog_head, | |
74 | (head + 1) & (size - 1)); | |
75 | } | |
76 | ||
77 | head = b->conn_backlog_head; | |
78 | tail = READ_ONCE(b->conn_backlog_tail); | |
79 | if (CIRC_CNT(head, tail, size) < max) { | |
80 | struct rxrpc_connection *conn; | |
81 | ||
82 | conn = rxrpc_prealloc_service_connection(gfp); | |
83 | if (!conn) | |
84 | return -ENOMEM; | |
85 | b->conn_backlog[head] = conn; | |
86 | smp_store_release(&b->conn_backlog_head, | |
87 | (head + 1) & (size - 1)); | |
88 | } | |
89 | ||
90 | /* Now it gets complicated, because calls get registered with the | |
91 | * socket here, particularly if a user ID is preassigned by the user. | |
92 | */ | |
93 | call = rxrpc_alloc_call(gfp); | |
94 | if (!call) | |
95 | return -ENOMEM; | |
96 | call->flags |= (1 << RXRPC_CALL_IS_SERVICE); | |
97 | call->state = RXRPC_CALL_SERVER_PREALLOC; | |
98 | ||
99 | trace_rxrpc_call(call, rxrpc_call_new_service, | |
100 | atomic_read(&call->usage), | |
101 | here, (const void *)user_call_ID); | |
102 | ||
103 | write_lock(&rx->call_lock); | |
104 | if (user_attach_call) { | |
105 | struct rxrpc_call *xcall; | |
106 | struct rb_node *parent, **pp; | |
107 | ||
108 | /* Check the user ID isn't already in use */ | |
109 | pp = &rx->calls.rb_node; | |
110 | parent = NULL; | |
111 | while (*pp) { | |
112 | parent = *pp; | |
113 | xcall = rb_entry(parent, struct rxrpc_call, sock_node); | |
114 | if (user_call_ID < call->user_call_ID) | |
115 | pp = &(*pp)->rb_left; | |
116 | else if (user_call_ID > call->user_call_ID) | |
117 | pp = &(*pp)->rb_right; | |
118 | else | |
119 | goto id_in_use; | |
120 | } | |
121 | ||
122 | call->user_call_ID = user_call_ID; | |
123 | call->notify_rx = notify_rx; | |
124 | rxrpc_get_call(call, rxrpc_call_got); | |
125 | user_attach_call(call, user_call_ID); | |
126 | rxrpc_get_call(call, rxrpc_call_got_userid); | |
127 | rb_link_node(&call->sock_node, parent, pp); | |
128 | rb_insert_color(&call->sock_node, &rx->calls); | |
129 | set_bit(RXRPC_CALL_HAS_USERID, &call->flags); | |
130 | } | |
131 | ||
248f219c DH |
132 | list_add(&call->sock_link, &rx->sock_calls); |
133 | ||
00e90712 DH |
134 | write_unlock(&rx->call_lock); |
135 | ||
136 | write_lock(&rxrpc_call_lock); | |
137 | list_add_tail(&call->link, &rxrpc_calls); | |
138 | write_unlock(&rxrpc_call_lock); | |
139 | ||
140 | b->call_backlog[call_head] = call; | |
141 | smp_store_release(&b->call_backlog_head, (call_head + 1) & (size - 1)); | |
142 | _leave(" = 0 [%d -> %lx]", call->debug_id, user_call_ID); | |
143 | return 0; | |
144 | ||
145 | id_in_use: | |
146 | write_unlock(&rx->call_lock); | |
147 | rxrpc_cleanup_call(call); | |
148 | _leave(" = -EBADSLT"); | |
149 | return -EBADSLT; | |
150 | } | |
151 | ||
152 | /* | |
153 | * Preallocate sufficient service connections, calls and peers to cover the | |
154 | * entire backlog of a socket. When a new call comes in, if we don't have | |
155 | * sufficient of each available, the call gets rejected as busy or ignored. | |
156 | * | |
157 | * The backlog is replenished when a connection is accepted or rejected. | |
158 | */ | |
159 | int rxrpc_service_prealloc(struct rxrpc_sock *rx, gfp_t gfp) | |
160 | { | |
161 | struct rxrpc_backlog *b = rx->backlog; | |
162 | ||
163 | if (!b) { | |
164 | b = kzalloc(sizeof(struct rxrpc_backlog), gfp); | |
165 | if (!b) | |
166 | return -ENOMEM; | |
167 | rx->backlog = b; | |
168 | } | |
169 | ||
170 | if (rx->discard_new_call) | |
171 | return 0; | |
172 | ||
173 | while (rxrpc_service_prealloc_one(rx, b, NULL, NULL, 0, gfp) == 0) | |
174 | ; | |
175 | ||
176 | return 0; | |
177 | } | |
178 | ||
179 | /* | |
180 | * Discard the preallocation on a service. | |
181 | */ | |
182 | void rxrpc_discard_prealloc(struct rxrpc_sock *rx) | |
183 | { | |
184 | struct rxrpc_backlog *b = rx->backlog; | |
185 | unsigned int size = RXRPC_BACKLOG_MAX, head, tail; | |
186 | ||
187 | if (!b) | |
188 | return; | |
189 | rx->backlog = NULL; | |
190 | ||
248f219c DH |
191 | /* Make sure that there aren't any incoming calls in progress before we |
192 | * clear the preallocation buffers. | |
193 | */ | |
194 | spin_lock_bh(&rx->incoming_lock); | |
195 | spin_unlock_bh(&rx->incoming_lock); | |
196 | ||
00e90712 DH |
197 | head = b->peer_backlog_head; |
198 | tail = b->peer_backlog_tail; | |
199 | while (CIRC_CNT(head, tail, size) > 0) { | |
200 | struct rxrpc_peer *peer = b->peer_backlog[tail]; | |
201 | kfree(peer); | |
202 | tail = (tail + 1) & (size - 1); | |
203 | } | |
204 | ||
205 | head = b->conn_backlog_head; | |
206 | tail = b->conn_backlog_tail; | |
207 | while (CIRC_CNT(head, tail, size) > 0) { | |
208 | struct rxrpc_connection *conn = b->conn_backlog[tail]; | |
209 | write_lock(&rxrpc_connection_lock); | |
210 | list_del(&conn->link); | |
211 | list_del(&conn->proc_link); | |
212 | write_unlock(&rxrpc_connection_lock); | |
213 | kfree(conn); | |
214 | tail = (tail + 1) & (size - 1); | |
215 | } | |
216 | ||
217 | head = b->call_backlog_head; | |
218 | tail = b->call_backlog_tail; | |
219 | while (CIRC_CNT(head, tail, size) > 0) { | |
220 | struct rxrpc_call *call = b->call_backlog[tail]; | |
221 | if (rx->discard_new_call) { | |
222 | _debug("discard %lx", call->user_call_ID); | |
223 | rx->discard_new_call(call, call->user_call_ID); | |
224 | } | |
225 | rxrpc_call_completed(call); | |
226 | rxrpc_release_call(rx, call); | |
227 | rxrpc_put_call(call, rxrpc_call_put); | |
228 | tail = (tail + 1) & (size - 1); | |
229 | } | |
230 | ||
231 | kfree(b); | |
232 | } | |
233 | ||
17926a79 | 234 | /* |
248f219c DH |
235 | * Allocate a new incoming call from the prealloc pool, along with a connection |
236 | * and a peer as necessary. | |
17926a79 | 237 | */ |
248f219c DH |
238 | static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx, |
239 | struct rxrpc_local *local, | |
240 | struct rxrpc_connection *conn, | |
241 | struct sk_buff *skb) | |
17926a79 | 242 | { |
248f219c DH |
243 | struct rxrpc_backlog *b = rx->backlog; |
244 | struct rxrpc_peer *peer, *xpeer; | |
245 | struct rxrpc_call *call; | |
246 | unsigned short call_head, conn_head, peer_head; | |
247 | unsigned short call_tail, conn_tail, peer_tail; | |
248 | unsigned short call_count, conn_count; | |
249 | ||
250 | /* #calls >= #conns >= #peers must hold true. */ | |
251 | call_head = smp_load_acquire(&b->call_backlog_head); | |
252 | call_tail = b->call_backlog_tail; | |
253 | call_count = CIRC_CNT(call_head, call_tail, RXRPC_BACKLOG_MAX); | |
254 | conn_head = smp_load_acquire(&b->conn_backlog_head); | |
255 | conn_tail = b->conn_backlog_tail; | |
256 | conn_count = CIRC_CNT(conn_head, conn_tail, RXRPC_BACKLOG_MAX); | |
257 | ASSERTCMP(conn_count, >=, call_count); | |
258 | peer_head = smp_load_acquire(&b->peer_backlog_head); | |
259 | peer_tail = b->peer_backlog_tail; | |
260 | ASSERTCMP(CIRC_CNT(peer_head, peer_tail, RXRPC_BACKLOG_MAX), >=, | |
261 | conn_count); | |
262 | ||
263 | if (call_count == 0) | |
264 | return NULL; | |
265 | ||
266 | if (!conn) { | |
267 | /* No connection. We're going to need a peer to start off | |
268 | * with. If one doesn't yet exist, use a spare from the | |
269 | * preallocation set. We dump the address into the spare in | |
270 | * anticipation - and to save on stack space. | |
271 | */ | |
272 | xpeer = b->peer_backlog[peer_tail]; | |
273 | if (rxrpc_extract_addr_from_skb(&xpeer->srx, skb) < 0) | |
274 | return NULL; | |
275 | ||
276 | peer = rxrpc_lookup_incoming_peer(local, xpeer); | |
277 | if (peer == xpeer) { | |
278 | b->peer_backlog[peer_tail] = NULL; | |
279 | smp_store_release(&b->peer_backlog_tail, | |
280 | (peer_tail + 1) & | |
281 | (RXRPC_BACKLOG_MAX - 1)); | |
282 | } | |
17926a79 | 283 | |
248f219c DH |
284 | /* Now allocate and set up the connection */ |
285 | conn = b->conn_backlog[conn_tail]; | |
286 | b->conn_backlog[conn_tail] = NULL; | |
287 | smp_store_release(&b->conn_backlog_tail, | |
288 | (conn_tail + 1) & (RXRPC_BACKLOG_MAX - 1)); | |
289 | rxrpc_get_local(local); | |
290 | conn->params.local = local; | |
291 | conn->params.peer = peer; | |
292 | rxrpc_new_incoming_connection(conn, skb); | |
293 | } else { | |
294 | rxrpc_get_connection(conn); | |
17926a79 DH |
295 | } |
296 | ||
248f219c DH |
297 | /* And now we can allocate and set up a new call */ |
298 | call = b->call_backlog[call_tail]; | |
299 | b->call_backlog[call_tail] = NULL; | |
300 | smp_store_release(&b->call_backlog_tail, | |
301 | (call_tail + 1) & (RXRPC_BACKLOG_MAX - 1)); | |
302 | ||
303 | call->conn = conn; | |
304 | call->peer = rxrpc_get_peer(conn->params.peer); | |
305 | return call; | |
17926a79 DH |
306 | } |
307 | ||
308 | /* | |
248f219c DH |
309 | * Set up a new incoming call. Called in BH context with the RCU read lock |
310 | * held. | |
311 | * | |
312 | * If this is for a kernel service, when we allocate the call, it will have | |
313 | * three refs on it: (1) the kernel service, (2) the user_call_ID tree, (3) the | |
314 | * retainer ref obtained from the backlog buffer. Prealloc calls for userspace | |
315 | * services only have the ref from the backlog buffer. We want to pass this | |
316 | * ref to non-BH context to dispose of. | |
317 | * | |
318 | * If we want to report an error, we mark the skb with the packet type and | |
319 | * abort code and return NULL. | |
17926a79 | 320 | */ |
248f219c DH |
321 | struct rxrpc_call *rxrpc_new_incoming_call(struct rxrpc_local *local, |
322 | struct rxrpc_connection *conn, | |
323 | struct sk_buff *skb) | |
17926a79 | 324 | { |
248f219c DH |
325 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
326 | struct rxrpc_sock *rx; | |
17926a79 | 327 | struct rxrpc_call *call; |
17926a79 DH |
328 | |
329 | _enter(""); | |
330 | ||
248f219c DH |
331 | /* Get the socket providing the service */ |
332 | hlist_for_each_entry_rcu_bh(rx, &local->services, listen_link) { | |
333 | if (rx->srx.srx_service == sp->hdr.serviceId) | |
334 | goto found_service; | |
17926a79 DH |
335 | } |
336 | ||
248f219c DH |
337 | trace_rxrpc_abort("INV", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq, |
338 | RX_INVALID_OPERATION, EOPNOTSUPP); | |
339 | skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT; | |
340 | skb->priority = RX_INVALID_OPERATION; | |
341 | _leave(" = NULL [service]"); | |
342 | return NULL; | |
17926a79 | 343 | |
248f219c DH |
344 | found_service: |
345 | spin_lock(&rx->incoming_lock); | |
346 | if (rx->sk.sk_state == RXRPC_CLOSE) { | |
347 | trace_rxrpc_abort("CLS", sp->hdr.cid, sp->hdr.callNumber, | |
348 | sp->hdr.seq, RX_INVALID_OPERATION, ESHUTDOWN); | |
349 | skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT; | |
350 | skb->priority = RX_INVALID_OPERATION; | |
351 | _leave(" = NULL [close]"); | |
352 | call = NULL; | |
353 | goto out; | |
17926a79 | 354 | } |
17926a79 | 355 | |
248f219c DH |
356 | call = rxrpc_alloc_incoming_call(rx, local, conn, skb); |
357 | if (!call) { | |
358 | skb->mark = RXRPC_SKB_MARK_BUSY; | |
359 | _leave(" = NULL [busy]"); | |
360 | call = NULL; | |
361 | goto out; | |
362 | } | |
17926a79 | 363 | |
248f219c DH |
364 | /* Make the call live. */ |
365 | rxrpc_incoming_call(rx, call, skb); | |
366 | conn = call->conn; | |
17926a79 | 367 | |
248f219c DH |
368 | if (rx->notify_new_call) |
369 | rx->notify_new_call(&rx->sk, call, call->user_call_ID); | |
17926a79 | 370 | |
248f219c DH |
371 | spin_lock(&conn->state_lock); |
372 | switch (conn->state) { | |
373 | case RXRPC_CONN_SERVICE_UNSECURED: | |
374 | conn->state = RXRPC_CONN_SERVICE_CHALLENGING; | |
375 | set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events); | |
376 | rxrpc_queue_conn(call->conn); | |
377 | break; | |
17926a79 | 378 | |
248f219c DH |
379 | case RXRPC_CONN_SERVICE: |
380 | write_lock(&call->state_lock); | |
381 | if (rx->discard_new_call) | |
382 | call->state = RXRPC_CALL_SERVER_RECV_REQUEST; | |
383 | else | |
384 | call->state = RXRPC_CALL_SERVER_ACCEPTING; | |
385 | write_unlock(&call->state_lock); | |
386 | break; | |
17926a79 | 387 | |
248f219c DH |
388 | case RXRPC_CONN_REMOTELY_ABORTED: |
389 | rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED, | |
390 | conn->remote_abort, ECONNABORTED); | |
391 | break; | |
392 | case RXRPC_CONN_LOCALLY_ABORTED: | |
393 | rxrpc_abort_call("CON", call, sp->hdr.seq, | |
394 | conn->local_abort, ECONNABORTED); | |
395 | break; | |
17926a79 DH |
396 | default: |
397 | BUG(); | |
398 | } | |
248f219c | 399 | spin_unlock(&conn->state_lock); |
17926a79 | 400 | |
248f219c DH |
401 | if (call->state == RXRPC_CALL_SERVER_ACCEPTING) |
402 | rxrpc_notify_socket(call); | |
d991b4a3 | 403 | |
248f219c DH |
404 | _leave(" = %p{%d}", call, call->debug_id); |
405 | out: | |
406 | spin_unlock(&rx->incoming_lock); | |
407 | return call; | |
17926a79 DH |
408 | } |
409 | ||
410 | /* | |
411 | * handle acceptance of a call by userspace | |
412 | * - assign the user call ID to the call at the front of the queue | |
413 | */ | |
651350d1 | 414 | struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx, |
d001648e DH |
415 | unsigned long user_call_ID, |
416 | rxrpc_notify_rx_t notify_rx) | |
17926a79 DH |
417 | { |
418 | struct rxrpc_call *call; | |
419 | struct rb_node *parent, **pp; | |
420 | int ret; | |
421 | ||
422 | _enter(",%lx", user_call_ID); | |
423 | ||
424 | ASSERT(!irqs_disabled()); | |
425 | ||
426 | write_lock(&rx->call_lock); | |
427 | ||
428 | ret = -ENODATA; | |
248f219c | 429 | if (list_empty(&rx->to_be_accepted)) |
17926a79 DH |
430 | goto out; |
431 | ||
432 | /* check the user ID isn't already in use */ | |
17926a79 DH |
433 | pp = &rx->calls.rb_node; |
434 | parent = NULL; | |
435 | while (*pp) { | |
436 | parent = *pp; | |
437 | call = rb_entry(parent, struct rxrpc_call, sock_node); | |
438 | ||
439 | if (user_call_ID < call->user_call_ID) | |
440 | pp = &(*pp)->rb_left; | |
441 | else if (user_call_ID > call->user_call_ID) | |
442 | pp = &(*pp)->rb_right; | |
443 | else | |
248f219c | 444 | goto id_in_use; |
17926a79 DH |
445 | } |
446 | ||
248f219c DH |
447 | /* Dequeue the first call and check it's still valid. We gain |
448 | * responsibility for the queue's reference. | |
449 | */ | |
450 | call = list_entry(rx->to_be_accepted.next, | |
451 | struct rxrpc_call, accept_link); | |
17926a79 DH |
452 | list_del_init(&call->accept_link); |
453 | sk_acceptq_removed(&rx->sk); | |
e34d4234 | 454 | rxrpc_see_call(call); |
17926a79 DH |
455 | |
456 | write_lock_bh(&call->state_lock); | |
457 | switch (call->state) { | |
458 | case RXRPC_CALL_SERVER_ACCEPTING: | |
459 | call->state = RXRPC_CALL_SERVER_RECV_REQUEST; | |
460 | break; | |
f5c17aae DH |
461 | case RXRPC_CALL_COMPLETE: |
462 | ret = call->error; | |
17926a79 | 463 | goto out_release; |
17926a79 DH |
464 | default: |
465 | BUG(); | |
466 | } | |
467 | ||
468 | /* formalise the acceptance */ | |
248f219c | 469 | rxrpc_get_call(call, rxrpc_call_got); |
d001648e | 470 | call->notify_rx = notify_rx; |
17926a79 | 471 | call->user_call_ID = user_call_ID; |
248f219c | 472 | rxrpc_get_call(call, rxrpc_call_got_userid); |
17926a79 DH |
473 | rb_link_node(&call->sock_node, parent, pp); |
474 | rb_insert_color(&call->sock_node, &rx->calls); | |
475 | if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags)) | |
476 | BUG(); | |
17926a79 DH |
477 | |
478 | write_unlock_bh(&call->state_lock); | |
479 | write_unlock(&rx->call_lock); | |
248f219c DH |
480 | rxrpc_notify_socket(call); |
481 | rxrpc_service_prealloc(rx, GFP_KERNEL); | |
651350d1 DH |
482 | _leave(" = %p{%d}", call, call->debug_id); |
483 | return call; | |
484 | ||
651350d1 | 485 | out_release: |
248f219c | 486 | _debug("release %p", call); |
651350d1 | 487 | write_unlock_bh(&call->state_lock); |
8d94aa38 | 488 | write_unlock(&rx->call_lock); |
8d94aa38 | 489 | rxrpc_release_call(rx, call); |
248f219c DH |
490 | rxrpc_put_call(call, rxrpc_call_put); |
491 | goto out; | |
492 | ||
493 | id_in_use: | |
494 | ret = -EBADSLT; | |
651350d1 | 495 | write_unlock(&rx->call_lock); |
248f219c DH |
496 | out: |
497 | rxrpc_service_prealloc(rx, GFP_KERNEL); | |
651350d1 DH |
498 | _leave(" = %d", ret); |
499 | return ERR_PTR(ret); | |
500 | } | |
501 | ||
502 | /* | |
b4f1342f | 503 | * Handle rejection of a call by userspace |
651350d1 DH |
504 | * - reject the call at the front of the queue |
505 | */ | |
506 | int rxrpc_reject_call(struct rxrpc_sock *rx) | |
507 | { | |
508 | struct rxrpc_call *call; | |
248f219c | 509 | bool abort = false; |
651350d1 DH |
510 | int ret; |
511 | ||
512 | _enter(""); | |
513 | ||
514 | ASSERT(!irqs_disabled()); | |
515 | ||
516 | write_lock(&rx->call_lock); | |
517 | ||
248f219c | 518 | if (list_empty(&rx->to_be_accepted)) { |
8d94aa38 | 519 | write_unlock(&rx->call_lock); |
8d94aa38 DH |
520 | return -ENODATA; |
521 | } | |
651350d1 | 522 | |
248f219c DH |
523 | /* Dequeue the first call and check it's still valid. We gain |
524 | * responsibility for the queue's reference. | |
525 | */ | |
526 | call = list_entry(rx->to_be_accepted.next, | |
527 | struct rxrpc_call, accept_link); | |
651350d1 DH |
528 | list_del_init(&call->accept_link); |
529 | sk_acceptq_removed(&rx->sk); | |
e34d4234 | 530 | rxrpc_see_call(call); |
651350d1 DH |
531 | |
532 | write_lock_bh(&call->state_lock); | |
533 | switch (call->state) { | |
534 | case RXRPC_CALL_SERVER_ACCEPTING: | |
248f219c DH |
535 | __rxrpc_abort_call("REJ", call, 1, RX_USER_ABORT, ECONNABORTED); |
536 | abort = true; | |
537 | /* fall through */ | |
f5c17aae DH |
538 | case RXRPC_CALL_COMPLETE: |
539 | ret = call->error; | |
248f219c | 540 | goto out_discard; |
651350d1 DH |
541 | default: |
542 | BUG(); | |
543 | } | |
17926a79 | 544 | |
248f219c | 545 | out_discard: |
17926a79 | 546 | write_unlock_bh(&call->state_lock); |
17926a79 | 547 | write_unlock(&rx->call_lock); |
248f219c DH |
548 | if (abort) { |
549 | rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ABORT); | |
550 | rxrpc_release_call(rx, call); | |
551 | rxrpc_put_call(call, rxrpc_call_put); | |
552 | } | |
553 | rxrpc_service_prealloc(rx, GFP_KERNEL); | |
651350d1 DH |
554 | _leave(" = %d", ret); |
555 | return ret; | |
556 | } | |
00e90712 DH |
557 | |
558 | /* | |
559 | * rxrpc_kernel_charge_accept - Charge up socket with preallocated calls | |
560 | * @sock: The socket on which to preallocate | |
561 | * @notify_rx: Event notification function for the call | |
562 | * @user_attach_call: Func to attach call to user_call_ID | |
563 | * @user_call_ID: The tag to attach to the preallocated call | |
564 | * @gfp: The allocation conditions. | |
565 | * | |
566 | * Charge up the socket with preallocated calls, each with a user ID. A | |
567 | * function should be provided to effect the attachment from the user's side. | |
568 | * The user is given a ref to hold on the call. | |
569 | * | |
570 | * Note that the call may be come connected before this function returns. | |
571 | */ | |
572 | int rxrpc_kernel_charge_accept(struct socket *sock, | |
573 | rxrpc_notify_rx_t notify_rx, | |
574 | rxrpc_user_attach_call_t user_attach_call, | |
575 | unsigned long user_call_ID, gfp_t gfp) | |
576 | { | |
577 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); | |
578 | struct rxrpc_backlog *b = rx->backlog; | |
579 | ||
580 | if (sock->sk->sk_state == RXRPC_CLOSE) | |
581 | return -ESHUTDOWN; | |
582 | ||
583 | return rxrpc_service_prealloc_one(rx, b, notify_rx, | |
584 | user_attach_call, user_call_ID, | |
585 | gfp); | |
586 | } | |
587 | EXPORT_SYMBOL(rxrpc_kernel_charge_accept); |