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5c115590 AG |
1 | /* |
2 | * Copyright (c) 2006 Oracle. All rights reserved. | |
3 | * | |
4 | * This software is available to you under a choice of one of two | |
5 | * licenses. You may choose to be licensed under the terms of the GNU | |
6 | * General Public License (GPL) Version 2, available from the file | |
7 | * COPYING in the main directory of this source tree, or the | |
8 | * OpenIB.org BSD license below: | |
9 | * | |
10 | * Redistribution and use in source and binary forms, with or | |
11 | * without modification, are permitted provided that the following | |
12 | * conditions are met: | |
13 | * | |
14 | * - Redistributions of source code must retain the above | |
15 | * copyright notice, this list of conditions and the following | |
16 | * disclaimer. | |
17 | * | |
18 | * - Redistributions in binary form must reproduce the above | |
19 | * copyright notice, this list of conditions and the following | |
20 | * disclaimer in the documentation and/or other materials | |
21 | * provided with the distribution. | |
22 | * | |
23 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | |
24 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | |
25 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | |
26 | * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | |
27 | * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | |
28 | * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
29 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | |
30 | * SOFTWARE. | |
31 | * | |
32 | */ | |
33 | #include <linux/kernel.h> | |
5a0e3ad6 | 34 | #include <linux/gfp.h> |
5c115590 AG |
35 | #include <net/sock.h> |
36 | #include <linux/in.h> | |
37 | #include <linux/list.h> | |
38 | ||
39 | #include "rds.h" | |
5c115590 AG |
40 | |
41 | /* When transmitting messages in rds_send_xmit, we need to emerge from | |
42 | * time to time and briefly release the CPU. Otherwise the softlock watchdog | |
43 | * will kick our shin. | |
44 | * Also, it seems fairer to not let one busy connection stall all the | |
45 | * others. | |
46 | * | |
47 | * send_batch_count is the number of times we'll loop in send_xmit. Setting | |
48 | * it to 0 will restore the old behavior (where we looped until we had | |
49 | * drained the queue). | |
50 | */ | |
51 | static int send_batch_count = 64; | |
52 | module_param(send_batch_count, int, 0444); | |
53 | MODULE_PARM_DESC(send_batch_count, " batch factor when working the send queue"); | |
54 | ||
55 | /* | |
56 | * Reset the send state. Caller must hold c_send_lock when calling here. | |
57 | */ | |
58 | void rds_send_reset(struct rds_connection *conn) | |
59 | { | |
60 | struct rds_message *rm, *tmp; | |
61 | unsigned long flags; | |
62 | ||
63 | if (conn->c_xmit_rm) { | |
64 | /* Tell the user the RDMA op is no longer mapped by the | |
65 | * transport. This isn't entirely true (it's flushed out | |
66 | * independently) but as the connection is down, there's | |
67 | * no ongoing RDMA to/from that memory */ | |
68 | rds_message_unmapped(conn->c_xmit_rm); | |
69 | rds_message_put(conn->c_xmit_rm); | |
70 | conn->c_xmit_rm = NULL; | |
71 | } | |
72 | conn->c_xmit_sg = 0; | |
73 | conn->c_xmit_hdr_off = 0; | |
74 | conn->c_xmit_data_off = 0; | |
75 | conn->c_xmit_rdma_sent = 0; | |
15133f6e | 76 | conn->c_xmit_atomic_sent = 0; |
5c115590 AG |
77 | |
78 | conn->c_map_queued = 0; | |
79 | ||
80 | conn->c_unacked_packets = rds_sysctl_max_unacked_packets; | |
81 | conn->c_unacked_bytes = rds_sysctl_max_unacked_bytes; | |
82 | ||
83 | /* Mark messages as retransmissions, and move them to the send q */ | |
84 | spin_lock_irqsave(&conn->c_lock, flags); | |
85 | list_for_each_entry_safe(rm, tmp, &conn->c_retrans, m_conn_item) { | |
86 | set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); | |
87 | set_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags); | |
88 | } | |
89 | list_splice_init(&conn->c_retrans, &conn->c_send_queue); | |
90 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
91 | } | |
92 | ||
93 | /* | |
94 | * We're making the concious trade-off here to only send one message | |
95 | * down the connection at a time. | |
96 | * Pro: | |
97 | * - tx queueing is a simple fifo list | |
98 | * - reassembly is optional and easily done by transports per conn | |
99 | * - no per flow rx lookup at all, straight to the socket | |
100 | * - less per-frag memory and wire overhead | |
101 | * Con: | |
102 | * - queued acks can be delayed behind large messages | |
103 | * Depends: | |
104 | * - small message latency is higher behind queued large messages | |
105 | * - large message latency isn't starved by intervening small sends | |
106 | */ | |
107 | int rds_send_xmit(struct rds_connection *conn) | |
108 | { | |
109 | struct rds_message *rm; | |
110 | unsigned long flags; | |
111 | unsigned int tmp; | |
112 | unsigned int send_quota = send_batch_count; | |
113 | struct scatterlist *sg; | |
114 | int ret = 0; | |
115 | int was_empty = 0; | |
116 | LIST_HEAD(to_be_dropped); | |
117 | ||
118 | /* | |
119 | * sendmsg calls here after having queued its message on the send | |
120 | * queue. We only have one task feeding the connection at a time. If | |
121 | * another thread is already feeding the queue then we back off. This | |
122 | * avoids blocking the caller and trading per-connection data between | |
123 | * caches per message. | |
124 | * | |
125 | * The sem holder will issue a retry if they notice that someone queued | |
126 | * a message after they stopped walking the send queue but before they | |
127 | * dropped the sem. | |
128 | */ | |
129 | if (!mutex_trylock(&conn->c_send_lock)) { | |
130 | rds_stats_inc(s_send_sem_contention); | |
131 | ret = -ENOMEM; | |
132 | goto out; | |
133 | } | |
134 | ||
135 | if (conn->c_trans->xmit_prepare) | |
136 | conn->c_trans->xmit_prepare(conn); | |
137 | ||
138 | /* | |
139 | * spin trying to push headers and data down the connection until | |
140 | * the connection doens't make forward progress. | |
141 | */ | |
142 | while (--send_quota) { | |
143 | /* | |
144 | * See if need to send a congestion map update if we're | |
145 | * between sending messages. The send_sem protects our sole | |
146 | * use of c_map_offset and _bytes. | |
147 | * Note this is used only by transports that define a special | |
148 | * xmit_cong_map function. For all others, we create allocate | |
149 | * a cong_map message and treat it just like any other send. | |
150 | */ | |
151 | if (conn->c_map_bytes) { | |
152 | ret = conn->c_trans->xmit_cong_map(conn, conn->c_lcong, | |
6200ed77 | 153 | conn->c_map_offset); |
5c115590 AG |
154 | if (ret <= 0) |
155 | break; | |
156 | ||
157 | conn->c_map_offset += ret; | |
158 | conn->c_map_bytes -= ret; | |
159 | if (conn->c_map_bytes) | |
160 | continue; | |
161 | } | |
162 | ||
163 | /* If we're done sending the current message, clear the | |
164 | * offset and S/G temporaries. | |
165 | */ | |
166 | rm = conn->c_xmit_rm; | |
8690bfa1 | 167 | if (rm && |
5c115590 | 168 | conn->c_xmit_hdr_off == sizeof(struct rds_header) && |
e779137a | 169 | conn->c_xmit_sg == rm->data.m_nents) { |
5c115590 AG |
170 | conn->c_xmit_rm = NULL; |
171 | conn->c_xmit_sg = 0; | |
172 | conn->c_xmit_hdr_off = 0; | |
173 | conn->c_xmit_data_off = 0; | |
174 | conn->c_xmit_rdma_sent = 0; | |
15133f6e | 175 | conn->c_xmit_atomic_sent = 0; |
5c115590 AG |
176 | |
177 | /* Release the reference to the previous message. */ | |
178 | rds_message_put(rm); | |
179 | rm = NULL; | |
180 | } | |
181 | ||
182 | /* If we're asked to send a cong map update, do so. | |
183 | */ | |
8690bfa1 AG |
184 | if (!rm && test_and_clear_bit(0, &conn->c_map_queued)) { |
185 | if (conn->c_trans->xmit_cong_map) { | |
5c115590 AG |
186 | conn->c_map_offset = 0; |
187 | conn->c_map_bytes = sizeof(struct rds_header) + | |
188 | RDS_CONG_MAP_BYTES; | |
189 | continue; | |
190 | } | |
191 | ||
192 | rm = rds_cong_update_alloc(conn); | |
193 | if (IS_ERR(rm)) { | |
194 | ret = PTR_ERR(rm); | |
195 | break; | |
196 | } | |
197 | ||
198 | conn->c_xmit_rm = rm; | |
199 | } | |
200 | ||
201 | /* | |
202 | * Grab the next message from the send queue, if there is one. | |
203 | * | |
204 | * c_xmit_rm holds a ref while we're sending this message down | |
205 | * the connction. We can use this ref while holding the | |
206 | * send_sem.. rds_send_reset() is serialized with it. | |
207 | */ | |
8690bfa1 | 208 | if (!rm) { |
5c115590 AG |
209 | unsigned int len; |
210 | ||
211 | spin_lock_irqsave(&conn->c_lock, flags); | |
212 | ||
213 | if (!list_empty(&conn->c_send_queue)) { | |
214 | rm = list_entry(conn->c_send_queue.next, | |
215 | struct rds_message, | |
216 | m_conn_item); | |
217 | rds_message_addref(rm); | |
218 | ||
219 | /* | |
220 | * Move the message from the send queue to the retransmit | |
221 | * list right away. | |
222 | */ | |
223 | list_move_tail(&rm->m_conn_item, &conn->c_retrans); | |
224 | } | |
225 | ||
226 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
227 | ||
8690bfa1 | 228 | if (!rm) { |
5c115590 AG |
229 | was_empty = 1; |
230 | break; | |
231 | } | |
232 | ||
233 | /* Unfortunately, the way Infiniband deals with | |
234 | * RDMA to a bad MR key is by moving the entire | |
235 | * queue pair to error state. We cold possibly | |
236 | * recover from that, but right now we drop the | |
237 | * connection. | |
238 | * Therefore, we never retransmit messages with RDMA ops. | |
239 | */ | |
ff87e97a | 240 | if (rm->rdma.m_rdma_op.r_active && |
f64f9e71 | 241 | test_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags)) { |
5c115590 AG |
242 | spin_lock_irqsave(&conn->c_lock, flags); |
243 | if (test_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) | |
244 | list_move(&rm->m_conn_item, &to_be_dropped); | |
245 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
246 | rds_message_put(rm); | |
247 | continue; | |
248 | } | |
249 | ||
250 | /* Require an ACK every once in a while */ | |
251 | len = ntohl(rm->m_inc.i_hdr.h_len); | |
f64f9e71 JP |
252 | if (conn->c_unacked_packets == 0 || |
253 | conn->c_unacked_bytes < len) { | |
5c115590 AG |
254 | __set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); |
255 | ||
256 | conn->c_unacked_packets = rds_sysctl_max_unacked_packets; | |
257 | conn->c_unacked_bytes = rds_sysctl_max_unacked_bytes; | |
258 | rds_stats_inc(s_send_ack_required); | |
259 | } else { | |
260 | conn->c_unacked_bytes -= len; | |
261 | conn->c_unacked_packets--; | |
262 | } | |
263 | ||
264 | conn->c_xmit_rm = rm; | |
265 | } | |
266 | ||
15133f6e AG |
267 | |
268 | if (rm->atomic.op_active && !conn->c_xmit_atomic_sent) { | |
269 | ret = conn->c_trans->xmit_atomic(conn, &rm->atomic); | |
270 | if (ret) | |
271 | break; | |
272 | conn->c_xmit_atomic_sent = 1; | |
273 | /* The transport owns the mapped memory for now. | |
274 | * You can't unmap it while it's on the send queue */ | |
275 | set_bit(RDS_MSG_MAPPED, &rm->m_flags); | |
276 | } | |
277 | ||
5c115590 AG |
278 | /* |
279 | * Try and send an rdma message. Let's see if we can | |
280 | * keep this simple and require that the transport either | |
281 | * send the whole rdma or none of it. | |
282 | */ | |
ff87e97a AG |
283 | if (rm->rdma.m_rdma_op.r_active && !conn->c_xmit_rdma_sent) { |
284 | ret = conn->c_trans->xmit_rdma(conn, &rm->rdma.m_rdma_op); | |
5c115590 AG |
285 | if (ret) |
286 | break; | |
287 | conn->c_xmit_rdma_sent = 1; | |
288 | /* The transport owns the mapped memory for now. | |
289 | * You can't unmap it while it's on the send queue */ | |
290 | set_bit(RDS_MSG_MAPPED, &rm->m_flags); | |
291 | } | |
292 | ||
293 | if (conn->c_xmit_hdr_off < sizeof(struct rds_header) || | |
e779137a | 294 | conn->c_xmit_sg < rm->data.m_nents) { |
5c115590 AG |
295 | ret = conn->c_trans->xmit(conn, rm, |
296 | conn->c_xmit_hdr_off, | |
297 | conn->c_xmit_sg, | |
298 | conn->c_xmit_data_off); | |
299 | if (ret <= 0) | |
300 | break; | |
301 | ||
302 | if (conn->c_xmit_hdr_off < sizeof(struct rds_header)) { | |
303 | tmp = min_t(int, ret, | |
304 | sizeof(struct rds_header) - | |
305 | conn->c_xmit_hdr_off); | |
306 | conn->c_xmit_hdr_off += tmp; | |
307 | ret -= tmp; | |
308 | } | |
309 | ||
e779137a | 310 | sg = &rm->data.m_sg[conn->c_xmit_sg]; |
5c115590 AG |
311 | while (ret) { |
312 | tmp = min_t(int, ret, sg->length - | |
313 | conn->c_xmit_data_off); | |
314 | conn->c_xmit_data_off += tmp; | |
315 | ret -= tmp; | |
316 | if (conn->c_xmit_data_off == sg->length) { | |
317 | conn->c_xmit_data_off = 0; | |
318 | sg++; | |
319 | conn->c_xmit_sg++; | |
320 | BUG_ON(ret != 0 && | |
e779137a | 321 | conn->c_xmit_sg == rm->data.m_nents); |
5c115590 AG |
322 | } |
323 | } | |
324 | } | |
325 | } | |
326 | ||
327 | /* Nuke any messages we decided not to retransmit. */ | |
328 | if (!list_empty(&to_be_dropped)) | |
329 | rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED); | |
330 | ||
331 | if (conn->c_trans->xmit_complete) | |
332 | conn->c_trans->xmit_complete(conn); | |
333 | ||
334 | /* | |
335 | * We might be racing with another sender who queued a message but | |
336 | * backed off on noticing that we held the c_send_lock. If we check | |
337 | * for queued messages after dropping the sem then either we'll | |
338 | * see the queued message or the queuer will get the sem. If we | |
339 | * notice the queued message then we trigger an immediate retry. | |
340 | * | |
341 | * We need to be careful only to do this when we stopped processing | |
342 | * the send queue because it was empty. It's the only way we | |
343 | * stop processing the loop when the transport hasn't taken | |
344 | * responsibility for forward progress. | |
345 | */ | |
346 | mutex_unlock(&conn->c_send_lock); | |
347 | ||
348 | if (conn->c_map_bytes || (send_quota == 0 && !was_empty)) { | |
349 | /* We exhausted the send quota, but there's work left to | |
350 | * do. Return and (re-)schedule the send worker. | |
351 | */ | |
352 | ret = -EAGAIN; | |
353 | } | |
354 | ||
355 | if (ret == 0 && was_empty) { | |
356 | /* A simple bit test would be way faster than taking the | |
357 | * spin lock */ | |
358 | spin_lock_irqsave(&conn->c_lock, flags); | |
359 | if (!list_empty(&conn->c_send_queue)) { | |
360 | rds_stats_inc(s_send_sem_queue_raced); | |
361 | ret = -EAGAIN; | |
362 | } | |
363 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
364 | } | |
365 | out: | |
366 | return ret; | |
367 | } | |
368 | ||
369 | static void rds_send_sndbuf_remove(struct rds_sock *rs, struct rds_message *rm) | |
370 | { | |
371 | u32 len = be32_to_cpu(rm->m_inc.i_hdr.h_len); | |
372 | ||
373 | assert_spin_locked(&rs->rs_lock); | |
374 | ||
375 | BUG_ON(rs->rs_snd_bytes < len); | |
376 | rs->rs_snd_bytes -= len; | |
377 | ||
378 | if (rs->rs_snd_bytes == 0) | |
379 | rds_stats_inc(s_send_queue_empty); | |
380 | } | |
381 | ||
382 | static inline int rds_send_is_acked(struct rds_message *rm, u64 ack, | |
383 | is_acked_func is_acked) | |
384 | { | |
385 | if (is_acked) | |
386 | return is_acked(rm, ack); | |
387 | return be64_to_cpu(rm->m_inc.i_hdr.h_sequence) <= ack; | |
388 | } | |
389 | ||
390 | /* | |
391 | * Returns true if there are no messages on the send and retransmit queues | |
392 | * which have a sequence number greater than or equal to the given sequence | |
393 | * number. | |
394 | */ | |
395 | int rds_send_acked_before(struct rds_connection *conn, u64 seq) | |
396 | { | |
397 | struct rds_message *rm, *tmp; | |
398 | int ret = 1; | |
399 | ||
400 | spin_lock(&conn->c_lock); | |
401 | ||
402 | list_for_each_entry_safe(rm, tmp, &conn->c_retrans, m_conn_item) { | |
403 | if (be64_to_cpu(rm->m_inc.i_hdr.h_sequence) < seq) | |
404 | ret = 0; | |
405 | break; | |
406 | } | |
407 | ||
408 | list_for_each_entry_safe(rm, tmp, &conn->c_send_queue, m_conn_item) { | |
409 | if (be64_to_cpu(rm->m_inc.i_hdr.h_sequence) < seq) | |
410 | ret = 0; | |
411 | break; | |
412 | } | |
413 | ||
414 | spin_unlock(&conn->c_lock); | |
415 | ||
416 | return ret; | |
417 | } | |
418 | ||
419 | /* | |
420 | * This is pretty similar to what happens below in the ACK | |
421 | * handling code - except that we call here as soon as we get | |
422 | * the IB send completion on the RDMA op and the accompanying | |
423 | * message. | |
424 | */ | |
425 | void rds_rdma_send_complete(struct rds_message *rm, int status) | |
426 | { | |
427 | struct rds_sock *rs = NULL; | |
428 | struct rds_rdma_op *ro; | |
429 | struct rds_notifier *notifier; | |
9de0864c | 430 | unsigned long flags; |
5c115590 | 431 | |
9de0864c | 432 | spin_lock_irqsave(&rm->m_rs_lock, flags); |
5c115590 | 433 | |
ff87e97a | 434 | ro = &rm->rdma.m_rdma_op; |
f64f9e71 | 435 | if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) && |
ff87e97a | 436 | ro->r_active && ro->r_notify && ro->r_notifier) { |
5c115590 AG |
437 | notifier = ro->r_notifier; |
438 | rs = rm->m_rs; | |
439 | sock_hold(rds_rs_to_sk(rs)); | |
440 | ||
441 | notifier->n_status = status; | |
442 | spin_lock(&rs->rs_lock); | |
443 | list_add_tail(¬ifier->n_list, &rs->rs_notify_queue); | |
444 | spin_unlock(&rs->rs_lock); | |
445 | ||
446 | ro->r_notifier = NULL; | |
447 | } | |
448 | ||
9de0864c | 449 | spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
5c115590 AG |
450 | |
451 | if (rs) { | |
452 | rds_wake_sk_sleep(rs); | |
453 | sock_put(rds_rs_to_sk(rs)); | |
454 | } | |
455 | } | |
616b757a | 456 | EXPORT_SYMBOL_GPL(rds_rdma_send_complete); |
5c115590 | 457 | |
15133f6e AG |
458 | /* |
459 | * Just like above, except looks at atomic op | |
460 | */ | |
461 | void rds_atomic_send_complete(struct rds_message *rm, int status) | |
462 | { | |
463 | struct rds_sock *rs = NULL; | |
464 | struct rm_atomic_op *ao; | |
465 | struct rds_notifier *notifier; | |
466 | ||
467 | spin_lock(&rm->m_rs_lock); | |
468 | ||
469 | ao = &rm->atomic; | |
470 | if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) | |
471 | && ao->op_active && ao->op_notify && ao->op_notifier) { | |
472 | notifier = ao->op_notifier; | |
473 | rs = rm->m_rs; | |
474 | sock_hold(rds_rs_to_sk(rs)); | |
475 | ||
476 | notifier->n_status = status; | |
477 | spin_lock(&rs->rs_lock); | |
478 | list_add_tail(¬ifier->n_list, &rs->rs_notify_queue); | |
479 | spin_unlock(&rs->rs_lock); | |
480 | ||
481 | ao->op_notifier = NULL; | |
482 | } | |
483 | ||
484 | spin_unlock(&rm->m_rs_lock); | |
485 | ||
486 | if (rs) { | |
487 | rds_wake_sk_sleep(rs); | |
488 | sock_put(rds_rs_to_sk(rs)); | |
489 | } | |
490 | } | |
491 | EXPORT_SYMBOL_GPL(rds_atomic_send_complete); | |
492 | ||
5c115590 AG |
493 | /* |
494 | * This is the same as rds_rdma_send_complete except we | |
495 | * don't do any locking - we have all the ingredients (message, | |
496 | * socket, socket lock) and can just move the notifier. | |
497 | */ | |
498 | static inline void | |
499 | __rds_rdma_send_complete(struct rds_sock *rs, struct rds_message *rm, int status) | |
500 | { | |
501 | struct rds_rdma_op *ro; | |
502 | ||
ff87e97a AG |
503 | ro = &rm->rdma.m_rdma_op; |
504 | if (ro->r_active && ro->r_notify && ro->r_notifier) { | |
5c115590 AG |
505 | ro->r_notifier->n_status = status; |
506 | list_add_tail(&ro->r_notifier->n_list, &rs->rs_notify_queue); | |
507 | ro->r_notifier = NULL; | |
508 | } | |
509 | ||
510 | /* No need to wake the app - caller does this */ | |
511 | } | |
512 | ||
513 | /* | |
514 | * This is called from the IB send completion when we detect | |
515 | * a RDMA operation that failed with remote access error. | |
516 | * So speed is not an issue here. | |
517 | */ | |
518 | struct rds_message *rds_send_get_message(struct rds_connection *conn, | |
519 | struct rds_rdma_op *op) | |
520 | { | |
521 | struct rds_message *rm, *tmp, *found = NULL; | |
522 | unsigned long flags; | |
523 | ||
524 | spin_lock_irqsave(&conn->c_lock, flags); | |
525 | ||
526 | list_for_each_entry_safe(rm, tmp, &conn->c_retrans, m_conn_item) { | |
ff87e97a | 527 | if (&rm->rdma.m_rdma_op == op) { |
5c115590 AG |
528 | atomic_inc(&rm->m_refcount); |
529 | found = rm; | |
530 | goto out; | |
531 | } | |
532 | } | |
533 | ||
534 | list_for_each_entry_safe(rm, tmp, &conn->c_send_queue, m_conn_item) { | |
ff87e97a | 535 | if (&rm->rdma.m_rdma_op == op) { |
5c115590 AG |
536 | atomic_inc(&rm->m_refcount); |
537 | found = rm; | |
538 | break; | |
539 | } | |
540 | } | |
541 | ||
542 | out: | |
543 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
544 | ||
545 | return found; | |
546 | } | |
616b757a | 547 | EXPORT_SYMBOL_GPL(rds_send_get_message); |
5c115590 AG |
548 | |
549 | /* | |
550 | * This removes messages from the socket's list if they're on it. The list | |
551 | * argument must be private to the caller, we must be able to modify it | |
552 | * without locks. The messages must have a reference held for their | |
553 | * position on the list. This function will drop that reference after | |
554 | * removing the messages from the 'messages' list regardless of if it found | |
555 | * the messages on the socket list or not. | |
556 | */ | |
557 | void rds_send_remove_from_sock(struct list_head *messages, int status) | |
558 | { | |
561c7df6 | 559 | unsigned long flags; |
5c115590 AG |
560 | struct rds_sock *rs = NULL; |
561 | struct rds_message *rm; | |
562 | ||
5c115590 | 563 | while (!list_empty(messages)) { |
561c7df6 AG |
564 | int was_on_sock = 0; |
565 | ||
5c115590 AG |
566 | rm = list_entry(messages->next, struct rds_message, |
567 | m_conn_item); | |
568 | list_del_init(&rm->m_conn_item); | |
569 | ||
570 | /* | |
571 | * If we see this flag cleared then we're *sure* that someone | |
572 | * else beat us to removing it from the sock. If we race | |
573 | * with their flag update we'll get the lock and then really | |
574 | * see that the flag has been cleared. | |
575 | * | |
576 | * The message spinlock makes sure nobody clears rm->m_rs | |
577 | * while we're messing with it. It does not prevent the | |
578 | * message from being removed from the socket, though. | |
579 | */ | |
561c7df6 | 580 | spin_lock_irqsave(&rm->m_rs_lock, flags); |
5c115590 AG |
581 | if (!test_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) |
582 | goto unlock_and_drop; | |
583 | ||
584 | if (rs != rm->m_rs) { | |
585 | if (rs) { | |
5c115590 AG |
586 | rds_wake_sk_sleep(rs); |
587 | sock_put(rds_rs_to_sk(rs)); | |
588 | } | |
589 | rs = rm->m_rs; | |
5c115590 AG |
590 | sock_hold(rds_rs_to_sk(rs)); |
591 | } | |
048c15e6 | 592 | spin_lock(&rs->rs_lock); |
5c115590 AG |
593 | |
594 | if (test_and_clear_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) { | |
ff87e97a | 595 | struct rds_rdma_op *ro = &rm->rdma.m_rdma_op; |
5c115590 AG |
596 | struct rds_notifier *notifier; |
597 | ||
598 | list_del_init(&rm->m_sock_item); | |
599 | rds_send_sndbuf_remove(rs, rm); | |
600 | ||
ff87e97a | 601 | if (ro->r_active && ro->r_notifier && |
a63273d4 | 602 | (ro->r_notify || (ro->r_recverr && status))) { |
5c115590 AG |
603 | notifier = ro->r_notifier; |
604 | list_add_tail(¬ifier->n_list, | |
605 | &rs->rs_notify_queue); | |
606 | if (!notifier->n_status) | |
607 | notifier->n_status = status; | |
ff87e97a | 608 | rm->rdma.m_rdma_op.r_notifier = NULL; |
5c115590 | 609 | } |
561c7df6 | 610 | was_on_sock = 1; |
5c115590 AG |
611 | rm->m_rs = NULL; |
612 | } | |
048c15e6 | 613 | spin_unlock(&rs->rs_lock); |
5c115590 AG |
614 | |
615 | unlock_and_drop: | |
561c7df6 | 616 | spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
5c115590 | 617 | rds_message_put(rm); |
561c7df6 AG |
618 | if (was_on_sock) |
619 | rds_message_put(rm); | |
5c115590 AG |
620 | } |
621 | ||
622 | if (rs) { | |
5c115590 AG |
623 | rds_wake_sk_sleep(rs); |
624 | sock_put(rds_rs_to_sk(rs)); | |
625 | } | |
5c115590 AG |
626 | } |
627 | ||
628 | /* | |
629 | * Transports call here when they've determined that the receiver queued | |
630 | * messages up to, and including, the given sequence number. Messages are | |
631 | * moved to the retrans queue when rds_send_xmit picks them off the send | |
632 | * queue. This means that in the TCP case, the message may not have been | |
633 | * assigned the m_ack_seq yet - but that's fine as long as tcp_is_acked | |
634 | * checks the RDS_MSG_HAS_ACK_SEQ bit. | |
635 | * | |
636 | * XXX It's not clear to me how this is safely serialized with socket | |
637 | * destruction. Maybe it should bail if it sees SOCK_DEAD. | |
638 | */ | |
639 | void rds_send_drop_acked(struct rds_connection *conn, u64 ack, | |
640 | is_acked_func is_acked) | |
641 | { | |
642 | struct rds_message *rm, *tmp; | |
643 | unsigned long flags; | |
644 | LIST_HEAD(list); | |
645 | ||
646 | spin_lock_irqsave(&conn->c_lock, flags); | |
647 | ||
648 | list_for_each_entry_safe(rm, tmp, &conn->c_retrans, m_conn_item) { | |
649 | if (!rds_send_is_acked(rm, ack, is_acked)) | |
650 | break; | |
651 | ||
652 | list_move(&rm->m_conn_item, &list); | |
653 | clear_bit(RDS_MSG_ON_CONN, &rm->m_flags); | |
654 | } | |
655 | ||
656 | /* order flag updates with spin locks */ | |
657 | if (!list_empty(&list)) | |
658 | smp_mb__after_clear_bit(); | |
659 | ||
660 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
661 | ||
662 | /* now remove the messages from the sock list as needed */ | |
663 | rds_send_remove_from_sock(&list, RDS_RDMA_SUCCESS); | |
664 | } | |
616b757a | 665 | EXPORT_SYMBOL_GPL(rds_send_drop_acked); |
5c115590 AG |
666 | |
667 | void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) | |
668 | { | |
669 | struct rds_message *rm, *tmp; | |
670 | struct rds_connection *conn; | |
7c82eaf0 | 671 | unsigned long flags; |
5c115590 | 672 | LIST_HEAD(list); |
5c115590 AG |
673 | |
674 | /* get all the messages we're dropping under the rs lock */ | |
675 | spin_lock_irqsave(&rs->rs_lock, flags); | |
676 | ||
677 | list_for_each_entry_safe(rm, tmp, &rs->rs_send_queue, m_sock_item) { | |
678 | if (dest && (dest->sin_addr.s_addr != rm->m_daddr || | |
679 | dest->sin_port != rm->m_inc.i_hdr.h_dport)) | |
680 | continue; | |
681 | ||
5c115590 AG |
682 | list_move(&rm->m_sock_item, &list); |
683 | rds_send_sndbuf_remove(rs, rm); | |
684 | clear_bit(RDS_MSG_ON_SOCK, &rm->m_flags); | |
5c115590 AG |
685 | } |
686 | ||
687 | /* order flag updates with the rs lock */ | |
7c82eaf0 | 688 | smp_mb__after_clear_bit(); |
5c115590 AG |
689 | |
690 | spin_unlock_irqrestore(&rs->rs_lock, flags); | |
691 | ||
7c82eaf0 AG |
692 | if (list_empty(&list)) |
693 | return; | |
5c115590 | 694 | |
7c82eaf0 | 695 | /* Remove the messages from the conn */ |
5c115590 | 696 | list_for_each_entry(rm, &list, m_sock_item) { |
7c82eaf0 AG |
697 | |
698 | conn = rm->m_inc.i_conn; | |
5c115590 | 699 | |
9de0864c | 700 | spin_lock_irqsave(&conn->c_lock, flags); |
5c115590 | 701 | /* |
7c82eaf0 AG |
702 | * Maybe someone else beat us to removing rm from the conn. |
703 | * If we race with their flag update we'll get the lock and | |
704 | * then really see that the flag has been cleared. | |
5c115590 | 705 | */ |
7c82eaf0 AG |
706 | if (!test_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) { |
707 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
5c115590 | 708 | continue; |
5c115590 | 709 | } |
9de0864c AG |
710 | list_del_init(&rm->m_conn_item); |
711 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
5c115590 | 712 | |
7c82eaf0 AG |
713 | /* |
714 | * Couldn't grab m_rs_lock in top loop (lock ordering), | |
715 | * but we can now. | |
716 | */ | |
9de0864c | 717 | spin_lock_irqsave(&rm->m_rs_lock, flags); |
5c115590 | 718 | |
7c82eaf0 AG |
719 | spin_lock(&rs->rs_lock); |
720 | __rds_rdma_send_complete(rs, rm, RDS_RDMA_CANCELED); | |
721 | spin_unlock(&rs->rs_lock); | |
722 | ||
723 | rm->m_rs = NULL; | |
9de0864c | 724 | spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
7c82eaf0 | 725 | |
7c82eaf0 | 726 | rds_message_put(rm); |
7c82eaf0 | 727 | } |
5c115590 | 728 | |
7c82eaf0 | 729 | rds_wake_sk_sleep(rs); |
550a8002 | 730 | |
5c115590 AG |
731 | while (!list_empty(&list)) { |
732 | rm = list_entry(list.next, struct rds_message, m_sock_item); | |
733 | list_del_init(&rm->m_sock_item); | |
734 | ||
735 | rds_message_wait(rm); | |
736 | rds_message_put(rm); | |
737 | } | |
738 | } | |
739 | ||
740 | /* | |
741 | * we only want this to fire once so we use the callers 'queued'. It's | |
742 | * possible that another thread can race with us and remove the | |
743 | * message from the flow with RDS_CANCEL_SENT_TO. | |
744 | */ | |
745 | static int rds_send_queue_rm(struct rds_sock *rs, struct rds_connection *conn, | |
746 | struct rds_message *rm, __be16 sport, | |
747 | __be16 dport, int *queued) | |
748 | { | |
749 | unsigned long flags; | |
750 | u32 len; | |
751 | ||
752 | if (*queued) | |
753 | goto out; | |
754 | ||
755 | len = be32_to_cpu(rm->m_inc.i_hdr.h_len); | |
756 | ||
757 | /* this is the only place which holds both the socket's rs_lock | |
758 | * and the connection's c_lock */ | |
759 | spin_lock_irqsave(&rs->rs_lock, flags); | |
760 | ||
761 | /* | |
762 | * If there is a little space in sndbuf, we don't queue anything, | |
763 | * and userspace gets -EAGAIN. But poll() indicates there's send | |
764 | * room. This can lead to bad behavior (spinning) if snd_bytes isn't | |
765 | * freed up by incoming acks. So we check the *old* value of | |
766 | * rs_snd_bytes here to allow the last msg to exceed the buffer, | |
767 | * and poll() now knows no more data can be sent. | |
768 | */ | |
769 | if (rs->rs_snd_bytes < rds_sk_sndbuf(rs)) { | |
770 | rs->rs_snd_bytes += len; | |
771 | ||
772 | /* let recv side know we are close to send space exhaustion. | |
773 | * This is probably not the optimal way to do it, as this | |
774 | * means we set the flag on *all* messages as soon as our | |
775 | * throughput hits a certain threshold. | |
776 | */ | |
777 | if (rs->rs_snd_bytes >= rds_sk_sndbuf(rs) / 2) | |
778 | __set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); | |
779 | ||
780 | list_add_tail(&rm->m_sock_item, &rs->rs_send_queue); | |
781 | set_bit(RDS_MSG_ON_SOCK, &rm->m_flags); | |
782 | rds_message_addref(rm); | |
783 | rm->m_rs = rs; | |
784 | ||
785 | /* The code ordering is a little weird, but we're | |
786 | trying to minimize the time we hold c_lock */ | |
787 | rds_message_populate_header(&rm->m_inc.i_hdr, sport, dport, 0); | |
788 | rm->m_inc.i_conn = conn; | |
789 | rds_message_addref(rm); | |
790 | ||
791 | spin_lock(&conn->c_lock); | |
792 | rm->m_inc.i_hdr.h_sequence = cpu_to_be64(conn->c_next_tx_seq++); | |
793 | list_add_tail(&rm->m_conn_item, &conn->c_send_queue); | |
794 | set_bit(RDS_MSG_ON_CONN, &rm->m_flags); | |
795 | spin_unlock(&conn->c_lock); | |
796 | ||
797 | rdsdebug("queued msg %p len %d, rs %p bytes %d seq %llu\n", | |
798 | rm, len, rs, rs->rs_snd_bytes, | |
799 | (unsigned long long)be64_to_cpu(rm->m_inc.i_hdr.h_sequence)); | |
800 | ||
801 | *queued = 1; | |
802 | } | |
803 | ||
804 | spin_unlock_irqrestore(&rs->rs_lock, flags); | |
805 | out: | |
806 | return *queued; | |
807 | } | |
808 | ||
fc445084 AG |
809 | /* |
810 | * rds_message is getting to be quite complicated, and we'd like to allocate | |
811 | * it all in one go. This figures out how big it needs to be up front. | |
812 | */ | |
813 | static int rds_rm_size(struct msghdr *msg, int data_len) | |
814 | { | |
ff87e97a | 815 | struct cmsghdr *cmsg; |
fc445084 | 816 | int size = 0; |
ff87e97a AG |
817 | int retval; |
818 | ||
819 | for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { | |
820 | if (!CMSG_OK(msg, cmsg)) | |
821 | return -EINVAL; | |
822 | ||
823 | if (cmsg->cmsg_level != SOL_RDS) | |
824 | continue; | |
825 | ||
826 | switch (cmsg->cmsg_type) { | |
827 | case RDS_CMSG_RDMA_ARGS: | |
828 | retval = rds_rdma_extra_size(CMSG_DATA(cmsg)); | |
829 | if (retval < 0) | |
830 | return retval; | |
831 | size += retval; | |
832 | break; | |
833 | ||
834 | case RDS_CMSG_RDMA_DEST: | |
835 | case RDS_CMSG_RDMA_MAP: | |
836 | /* these are valid but do no add any size */ | |
837 | break; | |
838 | ||
15133f6e AG |
839 | case RDS_CMSG_ATOMIC_CSWP: |
840 | case RDS_CMSG_ATOMIC_FADD: | |
841 | size += sizeof(struct scatterlist); | |
842 | break; | |
843 | ||
ff87e97a AG |
844 | default: |
845 | return -EINVAL; | |
846 | } | |
847 | ||
848 | } | |
fc445084 | 849 | |
ff87e97a | 850 | size += ceil(data_len, PAGE_SIZE) * sizeof(struct scatterlist); |
fc445084 AG |
851 | |
852 | return size; | |
853 | } | |
854 | ||
5c115590 AG |
855 | static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm, |
856 | struct msghdr *msg, int *allocated_mr) | |
857 | { | |
858 | struct cmsghdr *cmsg; | |
859 | int ret = 0; | |
860 | ||
861 | for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { | |
862 | if (!CMSG_OK(msg, cmsg)) | |
863 | return -EINVAL; | |
864 | ||
865 | if (cmsg->cmsg_level != SOL_RDS) | |
866 | continue; | |
867 | ||
868 | /* As a side effect, RDMA_DEST and RDMA_MAP will set | |
15133f6e | 869 | * rm->rdma.m_rdma_cookie and rm->rdma.m_rdma_mr. |
5c115590 AG |
870 | */ |
871 | switch (cmsg->cmsg_type) { | |
872 | case RDS_CMSG_RDMA_ARGS: | |
873 | ret = rds_cmsg_rdma_args(rs, rm, cmsg); | |
874 | break; | |
875 | ||
876 | case RDS_CMSG_RDMA_DEST: | |
877 | ret = rds_cmsg_rdma_dest(rs, rm, cmsg); | |
878 | break; | |
879 | ||
880 | case RDS_CMSG_RDMA_MAP: | |
881 | ret = rds_cmsg_rdma_map(rs, rm, cmsg); | |
882 | if (!ret) | |
883 | *allocated_mr = 1; | |
884 | break; | |
15133f6e AG |
885 | case RDS_CMSG_ATOMIC_CSWP: |
886 | case RDS_CMSG_ATOMIC_FADD: | |
887 | ret = rds_cmsg_atomic(rs, rm, cmsg); | |
888 | break; | |
5c115590 AG |
889 | |
890 | default: | |
891 | return -EINVAL; | |
892 | } | |
893 | ||
894 | if (ret) | |
895 | break; | |
896 | } | |
897 | ||
898 | return ret; | |
899 | } | |
900 | ||
901 | int rds_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, | |
902 | size_t payload_len) | |
903 | { | |
904 | struct sock *sk = sock->sk; | |
905 | struct rds_sock *rs = rds_sk_to_rs(sk); | |
906 | struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name; | |
907 | __be32 daddr; | |
908 | __be16 dport; | |
909 | struct rds_message *rm = NULL; | |
910 | struct rds_connection *conn; | |
911 | int ret = 0; | |
912 | int queued = 0, allocated_mr = 0; | |
913 | int nonblock = msg->msg_flags & MSG_DONTWAIT; | |
1123fd73 | 914 | long timeo = sock_sndtimeo(sk, nonblock); |
5c115590 AG |
915 | |
916 | /* Mirror Linux UDP mirror of BSD error message compatibility */ | |
917 | /* XXX: Perhaps MSG_MORE someday */ | |
918 | if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_CMSG_COMPAT)) { | |
919 | printk(KERN_INFO "msg_flags 0x%08X\n", msg->msg_flags); | |
920 | ret = -EOPNOTSUPP; | |
921 | goto out; | |
922 | } | |
923 | ||
924 | if (msg->msg_namelen) { | |
925 | /* XXX fail non-unicast destination IPs? */ | |
926 | if (msg->msg_namelen < sizeof(*usin) || usin->sin_family != AF_INET) { | |
927 | ret = -EINVAL; | |
928 | goto out; | |
929 | } | |
930 | daddr = usin->sin_addr.s_addr; | |
931 | dport = usin->sin_port; | |
932 | } else { | |
933 | /* We only care about consistency with ->connect() */ | |
934 | lock_sock(sk); | |
935 | daddr = rs->rs_conn_addr; | |
936 | dport = rs->rs_conn_port; | |
937 | release_sock(sk); | |
938 | } | |
939 | ||
940 | /* racing with another thread binding seems ok here */ | |
941 | if (daddr == 0 || rs->rs_bound_addr == 0) { | |
942 | ret = -ENOTCONN; /* XXX not a great errno */ | |
943 | goto out; | |
944 | } | |
945 | ||
fc445084 AG |
946 | /* size of rm including all sgs */ |
947 | ret = rds_rm_size(msg, payload_len); | |
948 | if (ret < 0) | |
949 | goto out; | |
950 | ||
951 | rm = rds_message_alloc(ret, GFP_KERNEL); | |
952 | if (!rm) { | |
953 | ret = -ENOMEM; | |
5c115590 AG |
954 | goto out; |
955 | } | |
956 | ||
fc445084 AG |
957 | rm->data.m_sg = rds_message_alloc_sgs(rm, ceil(payload_len, PAGE_SIZE)); |
958 | /* XXX fix this to not allocate memory */ | |
959 | ret = rds_message_copy_from_user(rm, msg->msg_iov, payload_len); | |
960 | if (ret) | |
961 | goto out; | |
962 | ||
5c115590 AG |
963 | rm->m_daddr = daddr; |
964 | ||
5c115590 AG |
965 | /* rds_conn_create has a spinlock that runs with IRQ off. |
966 | * Caching the conn in the socket helps a lot. */ | |
967 | if (rs->rs_conn && rs->rs_conn->c_faddr == daddr) | |
968 | conn = rs->rs_conn; | |
969 | else { | |
970 | conn = rds_conn_create_outgoing(rs->rs_bound_addr, daddr, | |
971 | rs->rs_transport, | |
972 | sock->sk->sk_allocation); | |
973 | if (IS_ERR(conn)) { | |
974 | ret = PTR_ERR(conn); | |
975 | goto out; | |
976 | } | |
977 | rs->rs_conn = conn; | |
978 | } | |
979 | ||
49f69691 AG |
980 | /* Parse any control messages the user may have included. */ |
981 | ret = rds_cmsg_send(rs, rm, msg, &allocated_mr); | |
982 | if (ret) | |
983 | goto out; | |
984 | ||
ff87e97a | 985 | if ((rm->m_rdma_cookie || rm->rdma.m_rdma_op.r_active) && |
15133f6e | 986 | !conn->c_trans->xmit_rdma) { |
5c115590 AG |
987 | if (printk_ratelimit()) |
988 | printk(KERN_NOTICE "rdma_op %p conn xmit_rdma %p\n", | |
15133f6e AG |
989 | &rm->rdma.m_rdma_op, conn->c_trans->xmit_rdma); |
990 | ret = -EOPNOTSUPP; | |
991 | goto out; | |
992 | } | |
993 | ||
994 | if (rm->atomic.op_active && !conn->c_trans->xmit_atomic) { | |
995 | if (printk_ratelimit()) | |
996 | printk(KERN_NOTICE "atomic_op %p conn xmit_atomic %p\n", | |
997 | &rm->atomic, conn->c_trans->xmit_atomic); | |
5c115590 AG |
998 | ret = -EOPNOTSUPP; |
999 | goto out; | |
1000 | } | |
1001 | ||
1002 | /* If the connection is down, trigger a connect. We may | |
1003 | * have scheduled a delayed reconnect however - in this case | |
1004 | * we should not interfere. | |
1005 | */ | |
f64f9e71 JP |
1006 | if (rds_conn_state(conn) == RDS_CONN_DOWN && |
1007 | !test_and_set_bit(RDS_RECONNECT_PENDING, &conn->c_flags)) | |
5c115590 AG |
1008 | queue_delayed_work(rds_wq, &conn->c_conn_w, 0); |
1009 | ||
1010 | ret = rds_cong_wait(conn->c_fcong, dport, nonblock, rs); | |
b98ba52f AG |
1011 | if (ret) { |
1012 | rs->rs_seen_congestion = 1; | |
5c115590 | 1013 | goto out; |
b98ba52f | 1014 | } |
5c115590 AG |
1015 | |
1016 | while (!rds_send_queue_rm(rs, conn, rm, rs->rs_bound_port, | |
1017 | dport, &queued)) { | |
1018 | rds_stats_inc(s_send_queue_full); | |
1019 | /* XXX make sure this is reasonable */ | |
1020 | if (payload_len > rds_sk_sndbuf(rs)) { | |
1021 | ret = -EMSGSIZE; | |
1022 | goto out; | |
1023 | } | |
1024 | if (nonblock) { | |
1025 | ret = -EAGAIN; | |
1026 | goto out; | |
1027 | } | |
1028 | ||
aa395145 | 1029 | timeo = wait_event_interruptible_timeout(*sk_sleep(sk), |
5c115590 AG |
1030 | rds_send_queue_rm(rs, conn, rm, |
1031 | rs->rs_bound_port, | |
1032 | dport, | |
1033 | &queued), | |
1034 | timeo); | |
1035 | rdsdebug("sendmsg woke queued %d timeo %ld\n", queued, timeo); | |
1036 | if (timeo > 0 || timeo == MAX_SCHEDULE_TIMEOUT) | |
1037 | continue; | |
1038 | ||
1039 | ret = timeo; | |
1040 | if (ret == 0) | |
1041 | ret = -ETIMEDOUT; | |
1042 | goto out; | |
1043 | } | |
1044 | ||
1045 | /* | |
1046 | * By now we've committed to the send. We reuse rds_send_worker() | |
1047 | * to retry sends in the rds thread if the transport asks us to. | |
1048 | */ | |
1049 | rds_stats_inc(s_send_queued); | |
1050 | ||
1051 | if (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags)) | |
1052 | rds_send_worker(&conn->c_send_w.work); | |
1053 | ||
1054 | rds_message_put(rm); | |
1055 | return payload_len; | |
1056 | ||
1057 | out: | |
1058 | /* If the user included a RDMA_MAP cmsg, we allocated a MR on the fly. | |
1059 | * If the sendmsg goes through, we keep the MR. If it fails with EAGAIN | |
1060 | * or in any other way, we need to destroy the MR again */ | |
1061 | if (allocated_mr) | |
1062 | rds_rdma_unuse(rs, rds_rdma_cookie_key(rm->m_rdma_cookie), 1); | |
1063 | ||
1064 | if (rm) | |
1065 | rds_message_put(rm); | |
1066 | return ret; | |
1067 | } | |
1068 | ||
1069 | /* | |
1070 | * Reply to a ping packet. | |
1071 | */ | |
1072 | int | |
1073 | rds_send_pong(struct rds_connection *conn, __be16 dport) | |
1074 | { | |
1075 | struct rds_message *rm; | |
1076 | unsigned long flags; | |
1077 | int ret = 0; | |
1078 | ||
1079 | rm = rds_message_alloc(0, GFP_ATOMIC); | |
8690bfa1 | 1080 | if (!rm) { |
5c115590 AG |
1081 | ret = -ENOMEM; |
1082 | goto out; | |
1083 | } | |
1084 | ||
1085 | rm->m_daddr = conn->c_faddr; | |
1086 | ||
1087 | /* If the connection is down, trigger a connect. We may | |
1088 | * have scheduled a delayed reconnect however - in this case | |
1089 | * we should not interfere. | |
1090 | */ | |
f64f9e71 JP |
1091 | if (rds_conn_state(conn) == RDS_CONN_DOWN && |
1092 | !test_and_set_bit(RDS_RECONNECT_PENDING, &conn->c_flags)) | |
5c115590 AG |
1093 | queue_delayed_work(rds_wq, &conn->c_conn_w, 0); |
1094 | ||
1095 | ret = rds_cong_wait(conn->c_fcong, dport, 1, NULL); | |
1096 | if (ret) | |
1097 | goto out; | |
1098 | ||
1099 | spin_lock_irqsave(&conn->c_lock, flags); | |
1100 | list_add_tail(&rm->m_conn_item, &conn->c_send_queue); | |
1101 | set_bit(RDS_MSG_ON_CONN, &rm->m_flags); | |
1102 | rds_message_addref(rm); | |
1103 | rm->m_inc.i_conn = conn; | |
1104 | ||
1105 | rds_message_populate_header(&rm->m_inc.i_hdr, 0, dport, | |
1106 | conn->c_next_tx_seq); | |
1107 | conn->c_next_tx_seq++; | |
1108 | spin_unlock_irqrestore(&conn->c_lock, flags); | |
1109 | ||
1110 | rds_stats_inc(s_send_queued); | |
1111 | rds_stats_inc(s_send_pong); | |
1112 | ||
1113 | queue_delayed_work(rds_wq, &conn->c_send_w, 0); | |
1114 | rds_message_put(rm); | |
1115 | return 0; | |
1116 | ||
1117 | out: | |
1118 | if (rm) | |
1119 | rds_message_put(rm); | |
1120 | return ret; | |
1121 | } |