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1/*
2 * Copyright (c) 2006, 2019 Oracle and/or its affiliates. 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>
34#include <linux/slab.h>
35#include <net/sock.h>
36#include <linux/in.h>
37#include <linux/export.h>
38#include <linux/time.h>
39#include <linux/rds.h>
40
41#include "rds.h"
42
43void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
44 struct in6_addr *saddr)
45{
46 refcount_set(&inc->i_refcount, 1);
47 INIT_LIST_HEAD(&inc->i_item);
48 inc->i_conn = conn;
49 inc->i_saddr = *saddr;
50 inc->i_usercopy.rdma_cookie = 0;
51 inc->i_usercopy.rx_tstamp = ktime_set(0, 0);
52
53 memset(inc->i_rx_lat_trace, 0, sizeof(inc->i_rx_lat_trace));
54}
55EXPORT_SYMBOL_GPL(rds_inc_init);
56
57void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *cp,
58 struct in6_addr *saddr)
59{
60 refcount_set(&inc->i_refcount, 1);
61 INIT_LIST_HEAD(&inc->i_item);
62 inc->i_conn = cp->cp_conn;
63 inc->i_conn_path = cp;
64 inc->i_saddr = *saddr;
65 inc->i_usercopy.rdma_cookie = 0;
66 inc->i_usercopy.rx_tstamp = ktime_set(0, 0);
67}
68EXPORT_SYMBOL_GPL(rds_inc_path_init);
69
70static void rds_inc_addref(struct rds_incoming *inc)
71{
72 rdsdebug("addref inc %p ref %d\n", inc, refcount_read(&inc->i_refcount));
73 refcount_inc(&inc->i_refcount);
74}
75
76void rds_inc_put(struct rds_incoming *inc)
77{
78 rdsdebug("put inc %p ref %d\n", inc, refcount_read(&inc->i_refcount));
79 if (refcount_dec_and_test(&inc->i_refcount)) {
80 BUG_ON(!list_empty(&inc->i_item));
81
82 inc->i_conn->c_trans->inc_free(inc);
83 }
84}
85EXPORT_SYMBOL_GPL(rds_inc_put);
86
87static void rds_recv_rcvbuf_delta(struct rds_sock *rs, struct sock *sk,
88 struct rds_cong_map *map,
89 int delta, __be16 port)
90{
91 int now_congested;
92
93 if (delta == 0)
94 return;
95
96 rs->rs_rcv_bytes += delta;
97 if (delta > 0)
98 rds_stats_add(s_recv_bytes_added_to_socket, delta);
99 else
100 rds_stats_add(s_recv_bytes_removed_from_socket, -delta);
101
102 /* loop transport doesn't send/recv congestion updates */
103 if (rs->rs_transport->t_type == RDS_TRANS_LOOP)
104 return;
105
106 now_congested = rs->rs_rcv_bytes > rds_sk_rcvbuf(rs);
107
108 rdsdebug("rs %p (%pI6c:%u) recv bytes %d buf %d "
109 "now_cong %d delta %d\n",
110 rs, &rs->rs_bound_addr,
111 ntohs(rs->rs_bound_port), rs->rs_rcv_bytes,
112 rds_sk_rcvbuf(rs), now_congested, delta);
113
114 /* wasn't -> am congested */
115 if (!rs->rs_congested && now_congested) {
116 rs->rs_congested = 1;
117 rds_cong_set_bit(map, port);
118 rds_cong_queue_updates(map);
119 }
120 /* was -> aren't congested */
121 /* Require more free space before reporting uncongested to prevent
122 bouncing cong/uncong state too often */
123 else if (rs->rs_congested && (rs->rs_rcv_bytes < (rds_sk_rcvbuf(rs)/2))) {
124 rs->rs_congested = 0;
125 rds_cong_clear_bit(map, port);
126 rds_cong_queue_updates(map);
127 }
128
129 /* do nothing if no change in cong state */
130}
131
132static void rds_conn_peer_gen_update(struct rds_connection *conn,
133 u32 peer_gen_num)
134{
135 int i;
136 struct rds_message *rm, *tmp;
137 unsigned long flags;
138
139 WARN_ON(conn->c_trans->t_type != RDS_TRANS_TCP);
140 if (peer_gen_num != 0) {
141 if (conn->c_peer_gen_num != 0 &&
142 peer_gen_num != conn->c_peer_gen_num) {
143 for (i = 0; i < RDS_MPATH_WORKERS; i++) {
144 struct rds_conn_path *cp;
145
146 cp = &conn->c_path[i];
147 spin_lock_irqsave(&cp->cp_lock, flags);
148 cp->cp_next_tx_seq = 1;
149 cp->cp_next_rx_seq = 0;
150 list_for_each_entry_safe(rm, tmp,
151 &cp->cp_retrans,
152 m_conn_item) {
153 set_bit(RDS_MSG_FLUSH, &rm->m_flags);
154 }
155 spin_unlock_irqrestore(&cp->cp_lock, flags);
156 }
157 }
158 conn->c_peer_gen_num = peer_gen_num;
159 }
160}
161
162/*
163 * Process all extension headers that come with this message.
164 */
165static void rds_recv_incoming_exthdrs(struct rds_incoming *inc, struct rds_sock *rs)
166{
167 struct rds_header *hdr = &inc->i_hdr;
168 unsigned int pos = 0, type, len;
169 union {
170 struct rds_ext_header_version version;
171 struct rds_ext_header_rdma rdma;
172 struct rds_ext_header_rdma_dest rdma_dest;
173 } buffer;
174
175 while (1) {
176 len = sizeof(buffer);
177 type = rds_message_next_extension(hdr, &pos, &buffer, &len);
178 if (type == RDS_EXTHDR_NONE)
179 break;
180 /* Process extension header here */
181 switch (type) {
182 case RDS_EXTHDR_RDMA:
183 rds_rdma_unuse(rs, be32_to_cpu(buffer.rdma.h_rdma_rkey), 0);
184 break;
185
186 case RDS_EXTHDR_RDMA_DEST:
187 /* We ignore the size for now. We could stash it
188 * somewhere and use it for error checking. */
189 inc->i_usercopy.rdma_cookie = rds_rdma_make_cookie(
190 be32_to_cpu(buffer.rdma_dest.h_rdma_rkey),
191 be32_to_cpu(buffer.rdma_dest.h_rdma_offset));
192
193 break;
194 }
195 }
196}
197
198static void rds_recv_hs_exthdrs(struct rds_header *hdr,
199 struct rds_connection *conn)
200{
201 unsigned int pos = 0, type, len;
202 union {
203 struct rds_ext_header_version version;
204 u16 rds_npaths;
205 u32 rds_gen_num;
206 } buffer;
207 u32 new_peer_gen_num = 0;
208
209 while (1) {
210 len = sizeof(buffer);
211 type = rds_message_next_extension(hdr, &pos, &buffer, &len);
212 if (type == RDS_EXTHDR_NONE)
213 break;
214 /* Process extension header here */
215 switch (type) {
216 case RDS_EXTHDR_NPATHS:
217 conn->c_npaths = min_t(int, RDS_MPATH_WORKERS,
218 be16_to_cpu(buffer.rds_npaths));
219 break;
220 case RDS_EXTHDR_GEN_NUM:
221 new_peer_gen_num = be32_to_cpu(buffer.rds_gen_num);
222 break;
223 default:
224 pr_warn_ratelimited("ignoring unknown exthdr type "
225 "0x%x\n", type);
226 }
227 }
228 /* if RDS_EXTHDR_NPATHS was not found, default to a single-path */
229 conn->c_npaths = max_t(int, conn->c_npaths, 1);
230 conn->c_ping_triggered = 0;
231 rds_conn_peer_gen_update(conn, new_peer_gen_num);
232}
233
234/* rds_start_mprds() will synchronously start multiple paths when appropriate.
235 * The scheme is based on the following rules:
236 *
237 * 1. rds_sendmsg on first connect attempt sends the probe ping, with the
238 * sender's npaths (s_npaths)
239 * 2. rcvr of probe-ping knows the mprds_paths = min(s_npaths, r_npaths). It
240 * sends back a probe-pong with r_npaths. After that, if rcvr is the
241 * smaller ip addr, it starts rds_conn_path_connect_if_down on all
242 * mprds_paths.
243 * 3. sender gets woken up, and can move to rds_conn_path_connect_if_down.
244 * If it is the smaller ipaddr, rds_conn_path_connect_if_down can be
245 * called after reception of the probe-pong on all mprds_paths.
246 * Otherwise (sender of probe-ping is not the smaller ip addr): just call
247 * rds_conn_path_connect_if_down on the hashed path. (see rule 4)
248 * 4. rds_connect_worker must only trigger a connection if laddr < faddr.
249 * 5. sender may end up queuing the packet on the cp. will get sent out later.
250 * when connection is completed.
251 */
252static void rds_start_mprds(struct rds_connection *conn)
253{
254 int i;
255 struct rds_conn_path *cp;
256
257 if (conn->c_npaths > 1 &&
258 rds_addr_cmp(&conn->c_laddr, &conn->c_faddr) < 0) {
259 for (i = 0; i < conn->c_npaths; i++) {
260 cp = &conn->c_path[i];
261 rds_conn_path_connect_if_down(cp);
262 }
263 }
264}
265
266/*
267 * The transport must make sure that this is serialized against other
268 * rx and conn reset on this specific conn.
269 *
270 * We currently assert that only one fragmented message will be sent
271 * down a connection at a time. This lets us reassemble in the conn
272 * instead of per-flow which means that we don't have to go digging through
273 * flows to tear down partial reassembly progress on conn failure and
274 * we save flow lookup and locking for each frag arrival. It does mean
275 * that small messages will wait behind large ones. Fragmenting at all
276 * is only to reduce the memory consumption of pre-posted buffers.
277 *
278 * The caller passes in saddr and daddr instead of us getting it from the
279 * conn. This lets loopback, who only has one conn for both directions,
280 * tell us which roles the addrs in the conn are playing for this message.
281 */
282void rds_recv_incoming(struct rds_connection *conn, struct in6_addr *saddr,
283 struct in6_addr *daddr,
284 struct rds_incoming *inc, gfp_t gfp)
285{
286 struct rds_sock *rs = NULL;
287 struct sock *sk;
288 unsigned long flags;
289 struct rds_conn_path *cp;
290
291 inc->i_conn = conn;
292 inc->i_rx_jiffies = jiffies;
293 if (conn->c_trans->t_mp_capable)
294 cp = inc->i_conn_path;
295 else
296 cp = &conn->c_path[0];
297
298 rdsdebug("conn %p next %llu inc %p seq %llu len %u sport %u dport %u "
299 "flags 0x%x rx_jiffies %lu\n", conn,
300 (unsigned long long)cp->cp_next_rx_seq,
301 inc,
302 (unsigned long long)be64_to_cpu(inc->i_hdr.h_sequence),
303 be32_to_cpu(inc->i_hdr.h_len),
304 be16_to_cpu(inc->i_hdr.h_sport),
305 be16_to_cpu(inc->i_hdr.h_dport),
306 inc->i_hdr.h_flags,
307 inc->i_rx_jiffies);
308
309 /*
310 * Sequence numbers should only increase. Messages get their
311 * sequence number as they're queued in a sending conn. They
312 * can be dropped, though, if the sending socket is closed before
313 * they hit the wire. So sequence numbers can skip forward
314 * under normal operation. They can also drop back in the conn
315 * failover case as previously sent messages are resent down the
316 * new instance of a conn. We drop those, otherwise we have
317 * to assume that the next valid seq does not come after a
318 * hole in the fragment stream.
319 *
320 * The headers don't give us a way to realize if fragments of
321 * a message have been dropped. We assume that frags that arrive
322 * to a flow are part of the current message on the flow that is
323 * being reassembled. This means that senders can't drop messages
324 * from the sending conn until all their frags are sent.
325 *
326 * XXX we could spend more on the wire to get more robust failure
327 * detection, arguably worth it to avoid data corruption.
328 */
329 if (be64_to_cpu(inc->i_hdr.h_sequence) < cp->cp_next_rx_seq &&
330 (inc->i_hdr.h_flags & RDS_FLAG_RETRANSMITTED)) {
331 rds_stats_inc(s_recv_drop_old_seq);
332 goto out;
333 }
334 cp->cp_next_rx_seq = be64_to_cpu(inc->i_hdr.h_sequence) + 1;
335
336 if (rds_sysctl_ping_enable && inc->i_hdr.h_dport == 0) {
337 if (inc->i_hdr.h_sport == 0) {
338 rdsdebug("ignore ping with 0 sport from %pI6c\n",
339 saddr);
340 goto out;
341 }
342 rds_stats_inc(s_recv_ping);
343 rds_send_pong(cp, inc->i_hdr.h_sport);
344 /* if this is a handshake ping, start multipath if necessary */
345 if (RDS_HS_PROBE(be16_to_cpu(inc->i_hdr.h_sport),
346 be16_to_cpu(inc->i_hdr.h_dport))) {
347 rds_recv_hs_exthdrs(&inc->i_hdr, cp->cp_conn);
348 rds_start_mprds(cp->cp_conn);
349 }
350 goto out;
351 }
352
353 if (be16_to_cpu(inc->i_hdr.h_dport) == RDS_FLAG_PROBE_PORT &&
354 inc->i_hdr.h_sport == 0) {
355 rds_recv_hs_exthdrs(&inc->i_hdr, cp->cp_conn);
356 /* if this is a handshake pong, start multipath if necessary */
357 rds_start_mprds(cp->cp_conn);
358 wake_up(&cp->cp_conn->c_hs_waitq);
359 goto out;
360 }
361
362 rs = rds_find_bound(daddr, inc->i_hdr.h_dport, conn->c_bound_if);
363 if (!rs) {
364 rds_stats_inc(s_recv_drop_no_sock);
365 goto out;
366 }
367
368 /* Process extension headers */
369 rds_recv_incoming_exthdrs(inc, rs);
370
371 /* We can be racing with rds_release() which marks the socket dead. */
372 sk = rds_rs_to_sk(rs);
373
374 /* serialize with rds_release -> sock_orphan */
375 write_lock_irqsave(&rs->rs_recv_lock, flags);
376 if (!sock_flag(sk, SOCK_DEAD)) {
377 rdsdebug("adding inc %p to rs %p's recv queue\n", inc, rs);
378 rds_stats_inc(s_recv_queued);
379 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
380 be32_to_cpu(inc->i_hdr.h_len),
381 inc->i_hdr.h_dport);
382 if (sock_flag(sk, SOCK_RCVTSTAMP))
383 inc->i_usercopy.rx_tstamp = ktime_get_real();
384 rds_inc_addref(inc);
385 inc->i_rx_lat_trace[RDS_MSG_RX_END] = local_clock();
386 list_add_tail(&inc->i_item, &rs->rs_recv_queue);
387 __rds_wake_sk_sleep(sk);
388 } else {
389 rds_stats_inc(s_recv_drop_dead_sock);
390 }
391 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
392
393out:
394 if (rs)
395 rds_sock_put(rs);
396}
397EXPORT_SYMBOL_GPL(rds_recv_incoming);
398
399/*
400 * be very careful here. This is being called as the condition in
401 * wait_event_*() needs to cope with being called many times.
402 */
403static int rds_next_incoming(struct rds_sock *rs, struct rds_incoming **inc)
404{
405 unsigned long flags;
406
407 if (!*inc) {
408 read_lock_irqsave(&rs->rs_recv_lock, flags);
409 if (!list_empty(&rs->rs_recv_queue)) {
410 *inc = list_entry(rs->rs_recv_queue.next,
411 struct rds_incoming,
412 i_item);
413 rds_inc_addref(*inc);
414 }
415 read_unlock_irqrestore(&rs->rs_recv_lock, flags);
416 }
417
418 return *inc != NULL;
419}
420
421static int rds_still_queued(struct rds_sock *rs, struct rds_incoming *inc,
422 int drop)
423{
424 struct sock *sk = rds_rs_to_sk(rs);
425 int ret = 0;
426 unsigned long flags;
427
428 write_lock_irqsave(&rs->rs_recv_lock, flags);
429 if (!list_empty(&inc->i_item)) {
430 ret = 1;
431 if (drop) {
432 /* XXX make sure this i_conn is reliable */
433 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
434 -be32_to_cpu(inc->i_hdr.h_len),
435 inc->i_hdr.h_dport);
436 list_del_init(&inc->i_item);
437 rds_inc_put(inc);
438 }
439 }
440 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
441
442 rdsdebug("inc %p rs %p still %d dropped %d\n", inc, rs, ret, drop);
443 return ret;
444}
445
446/*
447 * Pull errors off the error queue.
448 * If msghdr is NULL, we will just purge the error queue.
449 */
450int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msghdr)
451{
452 struct rds_notifier *notifier;
453 struct rds_rdma_notify cmsg = { 0 }; /* fill holes with zero */
454 unsigned int count = 0, max_messages = ~0U;
455 unsigned long flags;
456 LIST_HEAD(copy);
457 int err = 0;
458
459
460 /* put_cmsg copies to user space and thus may sleep. We can't do this
461 * with rs_lock held, so first grab as many notifications as we can stuff
462 * in the user provided cmsg buffer. We don't try to copy more, to avoid
463 * losing notifications - except when the buffer is so small that it wouldn't
464 * even hold a single notification. Then we give him as much of this single
465 * msg as we can squeeze in, and set MSG_CTRUNC.
466 */
467 if (msghdr) {
468 max_messages = msghdr->msg_controllen / CMSG_SPACE(sizeof(cmsg));
469 if (!max_messages)
470 max_messages = 1;
471 }
472
473 spin_lock_irqsave(&rs->rs_lock, flags);
474 while (!list_empty(&rs->rs_notify_queue) && count < max_messages) {
475 notifier = list_entry(rs->rs_notify_queue.next,
476 struct rds_notifier, n_list);
477 list_move(¬ifier->n_list, ©);
478 count++;
479 }
480 spin_unlock_irqrestore(&rs->rs_lock, flags);
481
482 if (!count)
483 return 0;
484
485 while (!list_empty(©)) {
486 notifier = list_entry(copy.next, struct rds_notifier, n_list);
487
488 if (msghdr) {
489 cmsg.user_token = notifier->n_user_token;
490 cmsg.status = notifier->n_status;
491
492 err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_RDMA_STATUS,
493 sizeof(cmsg), &cmsg);
494 if (err)
495 break;
496 }
497
498 list_del_init(¬ifier->n_list);
499 kfree(notifier);
500 }
501
502 /* If we bailed out because of an error in put_cmsg,
503 * we may be left with one or more notifications that we
504 * didn't process. Return them to the head of the list. */
505 if (!list_empty(©)) {
506 spin_lock_irqsave(&rs->rs_lock, flags);
507 list_splice(©, &rs->rs_notify_queue);
508 spin_unlock_irqrestore(&rs->rs_lock, flags);
509 }
510
511 return err;
512}
513
514/*
515 * Queue a congestion notification
516 */
517static int rds_notify_cong(struct rds_sock *rs, struct msghdr *msghdr)
518{
519 uint64_t notify = rs->rs_cong_notify;
520 unsigned long flags;
521 int err;
522
523 err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_CONG_UPDATE,
524 sizeof(notify), ¬ify);
525 if (err)
526 return err;
527
528 spin_lock_irqsave(&rs->rs_lock, flags);
529 rs->rs_cong_notify &= ~notify;
530 spin_unlock_irqrestore(&rs->rs_lock, flags);
531
532 return 0;
533}
534
535/*
536 * Receive any control messages.
537 */
538static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg,
539 struct rds_sock *rs)
540{
541 int ret = 0;
542
543 if (inc->i_usercopy.rdma_cookie) {
544 ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RDMA_DEST,
545 sizeof(inc->i_usercopy.rdma_cookie),
546 &inc->i_usercopy.rdma_cookie);
547 if (ret)
548 goto out;
549 }
550
551 if ((inc->i_usercopy.rx_tstamp != 0) &&
552 sock_flag(rds_rs_to_sk(rs), SOCK_RCVTSTAMP)) {
553 struct __kernel_old_timeval tv =
554 ns_to_kernel_old_timeval(inc->i_usercopy.rx_tstamp);
555
556 if (!sock_flag(rds_rs_to_sk(rs), SOCK_TSTAMP_NEW)) {
557 ret = put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
558 sizeof(tv), &tv);
559 } else {
560 struct __kernel_sock_timeval sk_tv;
561
562 sk_tv.tv_sec = tv.tv_sec;
563 sk_tv.tv_usec = tv.tv_usec;
564
565 ret = put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
566 sizeof(sk_tv), &sk_tv);
567 }
568
569 if (ret)
570 goto out;
571 }
572
573 if (rs->rs_rx_traces) {
574 struct rds_cmsg_rx_trace t;
575 int i, j;
576
577 memset(&t, 0, sizeof(t));
578 inc->i_rx_lat_trace[RDS_MSG_RX_CMSG] = local_clock();
579 t.rx_traces = rs->rs_rx_traces;
580 for (i = 0; i < rs->rs_rx_traces; i++) {
581 j = rs->rs_rx_trace[i];
582 t.rx_trace_pos[i] = j;
583 t.rx_trace[i] = inc->i_rx_lat_trace[j + 1] -
584 inc->i_rx_lat_trace[j];
585 }
586
587 ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RXPATH_LATENCY,
588 sizeof(t), &t);
589 if (ret)
590 goto out;
591 }
592
593out:
594 return ret;
595}
596
597static bool rds_recvmsg_zcookie(struct rds_sock *rs, struct msghdr *msg)
598{
599 struct rds_msg_zcopy_queue *q = &rs->rs_zcookie_queue;
600 struct rds_msg_zcopy_info *info = NULL;
601 struct rds_zcopy_cookies *done;
602 unsigned long flags;
603
604 if (!msg->msg_control)
605 return false;
606
607 if (!sock_flag(rds_rs_to_sk(rs), SOCK_ZEROCOPY) ||
608 msg->msg_controllen < CMSG_SPACE(sizeof(*done)))
609 return false;
610
611 spin_lock_irqsave(&q->lock, flags);
612 if (!list_empty(&q->zcookie_head)) {
613 info = list_entry(q->zcookie_head.next,
614 struct rds_msg_zcopy_info, rs_zcookie_next);
615 list_del(&info->rs_zcookie_next);
616 }
617 spin_unlock_irqrestore(&q->lock, flags);
618 if (!info)
619 return false;
620 done = &info->zcookies;
621 if (put_cmsg(msg, SOL_RDS, RDS_CMSG_ZCOPY_COMPLETION, sizeof(*done),
622 done)) {
623 spin_lock_irqsave(&q->lock, flags);
624 list_add(&info->rs_zcookie_next, &q->zcookie_head);
625 spin_unlock_irqrestore(&q->lock, flags);
626 return false;
627 }
628 kfree(info);
629 return true;
630}
631
632int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
633 int msg_flags)
634{
635 struct sock *sk = sock->sk;
636 struct rds_sock *rs = rds_sk_to_rs(sk);
637 long timeo;
638 int ret = 0, nonblock = msg_flags & MSG_DONTWAIT;
639 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
640 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
641 struct rds_incoming *inc = NULL;
642
643 /* udp_recvmsg()->sock_recvtimeo() gets away without locking too.. */
644 timeo = sock_rcvtimeo(sk, nonblock);
645
646 rdsdebug("size %zu flags 0x%x timeo %ld\n", size, msg_flags, timeo);
647
648 if (msg_flags & MSG_OOB)
649 goto out;
650 if (msg_flags & MSG_ERRQUEUE)
651 return sock_recv_errqueue(sk, msg, size, SOL_IP, IP_RECVERR);
652
653 while (1) {
654 /* If there are pending notifications, do those - and nothing else */
655 if (!list_empty(&rs->rs_notify_queue)) {
656 ret = rds_notify_queue_get(rs, msg);
657 break;
658 }
659
660 if (rs->rs_cong_notify) {
661 ret = rds_notify_cong(rs, msg);
662 break;
663 }
664
665 if (!rds_next_incoming(rs, &inc)) {
666 if (nonblock) {
667 bool reaped = rds_recvmsg_zcookie(rs, msg);
668
669 ret = reaped ? 0 : -EAGAIN;
670 break;
671 }
672
673 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
674 (!list_empty(&rs->rs_notify_queue) ||
675 rs->rs_cong_notify ||
676 rds_next_incoming(rs, &inc)), timeo);
677 rdsdebug("recvmsg woke inc %p timeo %ld\n", inc,
678 timeo);
679 if (timeo > 0 || timeo == MAX_SCHEDULE_TIMEOUT)
680 continue;
681
682 ret = timeo;
683 if (ret == 0)
684 ret = -ETIMEDOUT;
685 break;
686 }
687
688 rdsdebug("copying inc %p from %pI6c:%u to user\n", inc,
689 &inc->i_conn->c_faddr,
690 ntohs(inc->i_hdr.h_sport));
691 ret = inc->i_conn->c_trans->inc_copy_to_user(inc, &msg->msg_iter);
692 if (ret < 0)
693 break;
694
695 /*
696 * if the message we just copied isn't at the head of the
697 * recv queue then someone else raced us to return it, try
698 * to get the next message.
699 */
700 if (!rds_still_queued(rs, inc, !(msg_flags & MSG_PEEK))) {
701 rds_inc_put(inc);
702 inc = NULL;
703 rds_stats_inc(s_recv_deliver_raced);
704 iov_iter_revert(&msg->msg_iter, ret);
705 continue;
706 }
707
708 if (ret < be32_to_cpu(inc->i_hdr.h_len)) {
709 if (msg_flags & MSG_TRUNC)
710 ret = be32_to_cpu(inc->i_hdr.h_len);
711 msg->msg_flags |= MSG_TRUNC;
712 }
713
714 if (rds_cmsg_recv(inc, msg, rs)) {
715 ret = -EFAULT;
716 goto out;
717 }
718 rds_recvmsg_zcookie(rs, msg);
719
720 rds_stats_inc(s_recv_delivered);
721
722 if (msg->msg_name) {
723 if (ipv6_addr_v4mapped(&inc->i_saddr)) {
724 sin = (struct sockaddr_in *)msg->msg_name;
725
726 sin->sin_family = AF_INET;
727 sin->sin_port = inc->i_hdr.h_sport;
728 sin->sin_addr.s_addr =
729 inc->i_saddr.s6_addr32[3];
730 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
731 msg->msg_namelen = sizeof(*sin);
732 } else {
733 sin6 = (struct sockaddr_in6 *)msg->msg_name;
734
735 sin6->sin6_family = AF_INET6;
736 sin6->sin6_port = inc->i_hdr.h_sport;
737 sin6->sin6_addr = inc->i_saddr;
738 sin6->sin6_flowinfo = 0;
739 sin6->sin6_scope_id = rs->rs_bound_scope_id;
740 msg->msg_namelen = sizeof(*sin6);
741 }
742 }
743 break;
744 }
745
746 if (inc)
747 rds_inc_put(inc);
748
749out:
750 return ret;
751}
752
753/*
754 * The socket is being shut down and we're asked to drop messages that were
755 * queued for recvmsg. The caller has unbound the socket so the receive path
756 * won't queue any more incoming fragments or messages on the socket.
757 */
758void rds_clear_recv_queue(struct rds_sock *rs)
759{
760 struct sock *sk = rds_rs_to_sk(rs);
761 struct rds_incoming *inc, *tmp;
762 unsigned long flags;
763
764 write_lock_irqsave(&rs->rs_recv_lock, flags);
765 list_for_each_entry_safe(inc, tmp, &rs->rs_recv_queue, i_item) {
766 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
767 -be32_to_cpu(inc->i_hdr.h_len),
768 inc->i_hdr.h_dport);
769 list_del_init(&inc->i_item);
770 rds_inc_put(inc);
771 }
772 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
773}
774
775/*
776 * inc->i_saddr isn't used here because it is only set in the receive
777 * path.
778 */
779void rds_inc_info_copy(struct rds_incoming *inc,
780 struct rds_info_iterator *iter,
781 __be32 saddr, __be32 daddr, int flip)
782{
783 struct rds_info_message minfo;
784
785 minfo.seq = be64_to_cpu(inc->i_hdr.h_sequence);
786 minfo.len = be32_to_cpu(inc->i_hdr.h_len);
787 minfo.tos = inc->i_conn->c_tos;
788
789 if (flip) {
790 minfo.laddr = daddr;
791 minfo.faddr = saddr;
792 minfo.lport = inc->i_hdr.h_dport;
793 minfo.fport = inc->i_hdr.h_sport;
794 } else {
795 minfo.laddr = saddr;
796 minfo.faddr = daddr;
797 minfo.lport = inc->i_hdr.h_sport;
798 minfo.fport = inc->i_hdr.h_dport;
799 }
800
801 minfo.flags = 0;
802
803 rds_info_copy(iter, &minfo, sizeof(minfo));
804}
805
806#if IS_ENABLED(CONFIG_IPV6)
807void rds6_inc_info_copy(struct rds_incoming *inc,
808 struct rds_info_iterator *iter,
809 struct in6_addr *saddr, struct in6_addr *daddr,
810 int flip)
811{
812 struct rds6_info_message minfo6;
813
814 minfo6.seq = be64_to_cpu(inc->i_hdr.h_sequence);
815 minfo6.len = be32_to_cpu(inc->i_hdr.h_len);
816 minfo6.tos = inc->i_conn->c_tos;
817
818 if (flip) {
819 minfo6.laddr = *daddr;
820 minfo6.faddr = *saddr;
821 minfo6.lport = inc->i_hdr.h_dport;
822 minfo6.fport = inc->i_hdr.h_sport;
823 } else {
824 minfo6.laddr = *saddr;
825 minfo6.faddr = *daddr;
826 minfo6.lport = inc->i_hdr.h_sport;
827 minfo6.fport = inc->i_hdr.h_dport;
828 }
829
830 minfo6.flags = 0;
831
832 rds_info_copy(iter, &minfo6, sizeof(minfo6));
833}
834#endif
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>
34#include <linux/slab.h>
35#include <net/sock.h>
36#include <linux/in.h>
37#include <linux/export.h>
38
39#include "rds.h"
40
41void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
42 __be32 saddr)
43{
44 atomic_set(&inc->i_refcount, 1);
45 INIT_LIST_HEAD(&inc->i_item);
46 inc->i_conn = conn;
47 inc->i_saddr = saddr;
48 inc->i_rdma_cookie = 0;
49}
50EXPORT_SYMBOL_GPL(rds_inc_init);
51
52static void rds_inc_addref(struct rds_incoming *inc)
53{
54 rdsdebug("addref inc %p ref %d\n", inc, atomic_read(&inc->i_refcount));
55 atomic_inc(&inc->i_refcount);
56}
57
58void rds_inc_put(struct rds_incoming *inc)
59{
60 rdsdebug("put inc %p ref %d\n", inc, atomic_read(&inc->i_refcount));
61 if (atomic_dec_and_test(&inc->i_refcount)) {
62 BUG_ON(!list_empty(&inc->i_item));
63
64 inc->i_conn->c_trans->inc_free(inc);
65 }
66}
67EXPORT_SYMBOL_GPL(rds_inc_put);
68
69static void rds_recv_rcvbuf_delta(struct rds_sock *rs, struct sock *sk,
70 struct rds_cong_map *map,
71 int delta, __be16 port)
72{
73 int now_congested;
74
75 if (delta == 0)
76 return;
77
78 rs->rs_rcv_bytes += delta;
79 now_congested = rs->rs_rcv_bytes > rds_sk_rcvbuf(rs);
80
81 rdsdebug("rs %p (%pI4:%u) recv bytes %d buf %d "
82 "now_cong %d delta %d\n",
83 rs, &rs->rs_bound_addr,
84 ntohs(rs->rs_bound_port), rs->rs_rcv_bytes,
85 rds_sk_rcvbuf(rs), now_congested, delta);
86
87 /* wasn't -> am congested */
88 if (!rs->rs_congested && now_congested) {
89 rs->rs_congested = 1;
90 rds_cong_set_bit(map, port);
91 rds_cong_queue_updates(map);
92 }
93 /* was -> aren't congested */
94 /* Require more free space before reporting uncongested to prevent
95 bouncing cong/uncong state too often */
96 else if (rs->rs_congested && (rs->rs_rcv_bytes < (rds_sk_rcvbuf(rs)/2))) {
97 rs->rs_congested = 0;
98 rds_cong_clear_bit(map, port);
99 rds_cong_queue_updates(map);
100 }
101
102 /* do nothing if no change in cong state */
103}
104
105/*
106 * Process all extension headers that come with this message.
107 */
108static void rds_recv_incoming_exthdrs(struct rds_incoming *inc, struct rds_sock *rs)
109{
110 struct rds_header *hdr = &inc->i_hdr;
111 unsigned int pos = 0, type, len;
112 union {
113 struct rds_ext_header_version version;
114 struct rds_ext_header_rdma rdma;
115 struct rds_ext_header_rdma_dest rdma_dest;
116 } buffer;
117
118 while (1) {
119 len = sizeof(buffer);
120 type = rds_message_next_extension(hdr, &pos, &buffer, &len);
121 if (type == RDS_EXTHDR_NONE)
122 break;
123 /* Process extension header here */
124 switch (type) {
125 case RDS_EXTHDR_RDMA:
126 rds_rdma_unuse(rs, be32_to_cpu(buffer.rdma.h_rdma_rkey), 0);
127 break;
128
129 case RDS_EXTHDR_RDMA_DEST:
130 /* We ignore the size for now. We could stash it
131 * somewhere and use it for error checking. */
132 inc->i_rdma_cookie = rds_rdma_make_cookie(
133 be32_to_cpu(buffer.rdma_dest.h_rdma_rkey),
134 be32_to_cpu(buffer.rdma_dest.h_rdma_offset));
135
136 break;
137 }
138 }
139}
140
141/*
142 * The transport must make sure that this is serialized against other
143 * rx and conn reset on this specific conn.
144 *
145 * We currently assert that only one fragmented message will be sent
146 * down a connection at a time. This lets us reassemble in the conn
147 * instead of per-flow which means that we don't have to go digging through
148 * flows to tear down partial reassembly progress on conn failure and
149 * we save flow lookup and locking for each frag arrival. It does mean
150 * that small messages will wait behind large ones. Fragmenting at all
151 * is only to reduce the memory consumption of pre-posted buffers.
152 *
153 * The caller passes in saddr and daddr instead of us getting it from the
154 * conn. This lets loopback, who only has one conn for both directions,
155 * tell us which roles the addrs in the conn are playing for this message.
156 */
157void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,
158 struct rds_incoming *inc, gfp_t gfp)
159{
160 struct rds_sock *rs = NULL;
161 struct sock *sk;
162 unsigned long flags;
163
164 inc->i_conn = conn;
165 inc->i_rx_jiffies = jiffies;
166
167 rdsdebug("conn %p next %llu inc %p seq %llu len %u sport %u dport %u "
168 "flags 0x%x rx_jiffies %lu\n", conn,
169 (unsigned long long)conn->c_next_rx_seq,
170 inc,
171 (unsigned long long)be64_to_cpu(inc->i_hdr.h_sequence),
172 be32_to_cpu(inc->i_hdr.h_len),
173 be16_to_cpu(inc->i_hdr.h_sport),
174 be16_to_cpu(inc->i_hdr.h_dport),
175 inc->i_hdr.h_flags,
176 inc->i_rx_jiffies);
177
178 /*
179 * Sequence numbers should only increase. Messages get their
180 * sequence number as they're queued in a sending conn. They
181 * can be dropped, though, if the sending socket is closed before
182 * they hit the wire. So sequence numbers can skip forward
183 * under normal operation. They can also drop back in the conn
184 * failover case as previously sent messages are resent down the
185 * new instance of a conn. We drop those, otherwise we have
186 * to assume that the next valid seq does not come after a
187 * hole in the fragment stream.
188 *
189 * The headers don't give us a way to realize if fragments of
190 * a message have been dropped. We assume that frags that arrive
191 * to a flow are part of the current message on the flow that is
192 * being reassembled. This means that senders can't drop messages
193 * from the sending conn until all their frags are sent.
194 *
195 * XXX we could spend more on the wire to get more robust failure
196 * detection, arguably worth it to avoid data corruption.
197 */
198 if (be64_to_cpu(inc->i_hdr.h_sequence) < conn->c_next_rx_seq &&
199 (inc->i_hdr.h_flags & RDS_FLAG_RETRANSMITTED)) {
200 rds_stats_inc(s_recv_drop_old_seq);
201 goto out;
202 }
203 conn->c_next_rx_seq = be64_to_cpu(inc->i_hdr.h_sequence) + 1;
204
205 if (rds_sysctl_ping_enable && inc->i_hdr.h_dport == 0) {
206 rds_stats_inc(s_recv_ping);
207 rds_send_pong(conn, inc->i_hdr.h_sport);
208 goto out;
209 }
210
211 rs = rds_find_bound(daddr, inc->i_hdr.h_dport);
212 if (!rs) {
213 rds_stats_inc(s_recv_drop_no_sock);
214 goto out;
215 }
216
217 /* Process extension headers */
218 rds_recv_incoming_exthdrs(inc, rs);
219
220 /* We can be racing with rds_release() which marks the socket dead. */
221 sk = rds_rs_to_sk(rs);
222
223 /* serialize with rds_release -> sock_orphan */
224 write_lock_irqsave(&rs->rs_recv_lock, flags);
225 if (!sock_flag(sk, SOCK_DEAD)) {
226 rdsdebug("adding inc %p to rs %p's recv queue\n", inc, rs);
227 rds_stats_inc(s_recv_queued);
228 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
229 be32_to_cpu(inc->i_hdr.h_len),
230 inc->i_hdr.h_dport);
231 rds_inc_addref(inc);
232 list_add_tail(&inc->i_item, &rs->rs_recv_queue);
233 __rds_wake_sk_sleep(sk);
234 } else {
235 rds_stats_inc(s_recv_drop_dead_sock);
236 }
237 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
238
239out:
240 if (rs)
241 rds_sock_put(rs);
242}
243EXPORT_SYMBOL_GPL(rds_recv_incoming);
244
245/*
246 * be very careful here. This is being called as the condition in
247 * wait_event_*() needs to cope with being called many times.
248 */
249static int rds_next_incoming(struct rds_sock *rs, struct rds_incoming **inc)
250{
251 unsigned long flags;
252
253 if (!*inc) {
254 read_lock_irqsave(&rs->rs_recv_lock, flags);
255 if (!list_empty(&rs->rs_recv_queue)) {
256 *inc = list_entry(rs->rs_recv_queue.next,
257 struct rds_incoming,
258 i_item);
259 rds_inc_addref(*inc);
260 }
261 read_unlock_irqrestore(&rs->rs_recv_lock, flags);
262 }
263
264 return *inc != NULL;
265}
266
267static int rds_still_queued(struct rds_sock *rs, struct rds_incoming *inc,
268 int drop)
269{
270 struct sock *sk = rds_rs_to_sk(rs);
271 int ret = 0;
272 unsigned long flags;
273
274 write_lock_irqsave(&rs->rs_recv_lock, flags);
275 if (!list_empty(&inc->i_item)) {
276 ret = 1;
277 if (drop) {
278 /* XXX make sure this i_conn is reliable */
279 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
280 -be32_to_cpu(inc->i_hdr.h_len),
281 inc->i_hdr.h_dport);
282 list_del_init(&inc->i_item);
283 rds_inc_put(inc);
284 }
285 }
286 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
287
288 rdsdebug("inc %p rs %p still %d dropped %d\n", inc, rs, ret, drop);
289 return ret;
290}
291
292/*
293 * Pull errors off the error queue.
294 * If msghdr is NULL, we will just purge the error queue.
295 */
296int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msghdr)
297{
298 struct rds_notifier *notifier;
299 struct rds_rdma_notify cmsg = { 0 }; /* fill holes with zero */
300 unsigned int count = 0, max_messages = ~0U;
301 unsigned long flags;
302 LIST_HEAD(copy);
303 int err = 0;
304
305
306 /* put_cmsg copies to user space and thus may sleep. We can't do this
307 * with rs_lock held, so first grab as many notifications as we can stuff
308 * in the user provided cmsg buffer. We don't try to copy more, to avoid
309 * losing notifications - except when the buffer is so small that it wouldn't
310 * even hold a single notification. Then we give him as much of this single
311 * msg as we can squeeze in, and set MSG_CTRUNC.
312 */
313 if (msghdr) {
314 max_messages = msghdr->msg_controllen / CMSG_SPACE(sizeof(cmsg));
315 if (!max_messages)
316 max_messages = 1;
317 }
318
319 spin_lock_irqsave(&rs->rs_lock, flags);
320 while (!list_empty(&rs->rs_notify_queue) && count < max_messages) {
321 notifier = list_entry(rs->rs_notify_queue.next,
322 struct rds_notifier, n_list);
323 list_move(¬ifier->n_list, ©);
324 count++;
325 }
326 spin_unlock_irqrestore(&rs->rs_lock, flags);
327
328 if (!count)
329 return 0;
330
331 while (!list_empty(©)) {
332 notifier = list_entry(copy.next, struct rds_notifier, n_list);
333
334 if (msghdr) {
335 cmsg.user_token = notifier->n_user_token;
336 cmsg.status = notifier->n_status;
337
338 err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_RDMA_STATUS,
339 sizeof(cmsg), &cmsg);
340 if (err)
341 break;
342 }
343
344 list_del_init(¬ifier->n_list);
345 kfree(notifier);
346 }
347
348 /* If we bailed out because of an error in put_cmsg,
349 * we may be left with one or more notifications that we
350 * didn't process. Return them to the head of the list. */
351 if (!list_empty(©)) {
352 spin_lock_irqsave(&rs->rs_lock, flags);
353 list_splice(©, &rs->rs_notify_queue);
354 spin_unlock_irqrestore(&rs->rs_lock, flags);
355 }
356
357 return err;
358}
359
360/*
361 * Queue a congestion notification
362 */
363static int rds_notify_cong(struct rds_sock *rs, struct msghdr *msghdr)
364{
365 uint64_t notify = rs->rs_cong_notify;
366 unsigned long flags;
367 int err;
368
369 err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_CONG_UPDATE,
370 sizeof(notify), ¬ify);
371 if (err)
372 return err;
373
374 spin_lock_irqsave(&rs->rs_lock, flags);
375 rs->rs_cong_notify &= ~notify;
376 spin_unlock_irqrestore(&rs->rs_lock, flags);
377
378 return 0;
379}
380
381/*
382 * Receive any control messages.
383 */
384static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg)
385{
386 int ret = 0;
387
388 if (inc->i_rdma_cookie) {
389 ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RDMA_DEST,
390 sizeof(inc->i_rdma_cookie), &inc->i_rdma_cookie);
391 if (ret)
392 return ret;
393 }
394
395 return 0;
396}
397
398int rds_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
399 size_t size, int msg_flags)
400{
401 struct sock *sk = sock->sk;
402 struct rds_sock *rs = rds_sk_to_rs(sk);
403 long timeo;
404 int ret = 0, nonblock = msg_flags & MSG_DONTWAIT;
405 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
406 struct rds_incoming *inc = NULL;
407
408 /* udp_recvmsg()->sock_recvtimeo() gets away without locking too.. */
409 timeo = sock_rcvtimeo(sk, nonblock);
410
411 rdsdebug("size %zu flags 0x%x timeo %ld\n", size, msg_flags, timeo);
412
413 if (msg_flags & MSG_OOB)
414 goto out;
415
416 while (1) {
417 /* If there are pending notifications, do those - and nothing else */
418 if (!list_empty(&rs->rs_notify_queue)) {
419 ret = rds_notify_queue_get(rs, msg);
420 break;
421 }
422
423 if (rs->rs_cong_notify) {
424 ret = rds_notify_cong(rs, msg);
425 break;
426 }
427
428 if (!rds_next_incoming(rs, &inc)) {
429 if (nonblock) {
430 ret = -EAGAIN;
431 break;
432 }
433
434 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
435 (!list_empty(&rs->rs_notify_queue) ||
436 rs->rs_cong_notify ||
437 rds_next_incoming(rs, &inc)), timeo);
438 rdsdebug("recvmsg woke inc %p timeo %ld\n", inc,
439 timeo);
440 if (timeo > 0 || timeo == MAX_SCHEDULE_TIMEOUT)
441 continue;
442
443 ret = timeo;
444 if (ret == 0)
445 ret = -ETIMEDOUT;
446 break;
447 }
448
449 rdsdebug("copying inc %p from %pI4:%u to user\n", inc,
450 &inc->i_conn->c_faddr,
451 ntohs(inc->i_hdr.h_sport));
452 ret = inc->i_conn->c_trans->inc_copy_to_user(inc, msg->msg_iov,
453 size);
454 if (ret < 0)
455 break;
456
457 /*
458 * if the message we just copied isn't at the head of the
459 * recv queue then someone else raced us to return it, try
460 * to get the next message.
461 */
462 if (!rds_still_queued(rs, inc, !(msg_flags & MSG_PEEK))) {
463 rds_inc_put(inc);
464 inc = NULL;
465 rds_stats_inc(s_recv_deliver_raced);
466 continue;
467 }
468
469 if (ret < be32_to_cpu(inc->i_hdr.h_len)) {
470 if (msg_flags & MSG_TRUNC)
471 ret = be32_to_cpu(inc->i_hdr.h_len);
472 msg->msg_flags |= MSG_TRUNC;
473 }
474
475 if (rds_cmsg_recv(inc, msg)) {
476 ret = -EFAULT;
477 goto out;
478 }
479
480 rds_stats_inc(s_recv_delivered);
481
482 if (sin) {
483 sin->sin_family = AF_INET;
484 sin->sin_port = inc->i_hdr.h_sport;
485 sin->sin_addr.s_addr = inc->i_saddr;
486 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
487 msg->msg_namelen = sizeof(*sin);
488 }
489 break;
490 }
491
492 if (inc)
493 rds_inc_put(inc);
494
495out:
496 return ret;
497}
498
499/*
500 * The socket is being shut down and we're asked to drop messages that were
501 * queued for recvmsg. The caller has unbound the socket so the receive path
502 * won't queue any more incoming fragments or messages on the socket.
503 */
504void rds_clear_recv_queue(struct rds_sock *rs)
505{
506 struct sock *sk = rds_rs_to_sk(rs);
507 struct rds_incoming *inc, *tmp;
508 unsigned long flags;
509
510 write_lock_irqsave(&rs->rs_recv_lock, flags);
511 list_for_each_entry_safe(inc, tmp, &rs->rs_recv_queue, i_item) {
512 rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong,
513 -be32_to_cpu(inc->i_hdr.h_len),
514 inc->i_hdr.h_dport);
515 list_del_init(&inc->i_item);
516 rds_inc_put(inc);
517 }
518 write_unlock_irqrestore(&rs->rs_recv_lock, flags);
519}
520
521/*
522 * inc->i_saddr isn't used here because it is only set in the receive
523 * path.
524 */
525void rds_inc_info_copy(struct rds_incoming *inc,
526 struct rds_info_iterator *iter,
527 __be32 saddr, __be32 daddr, int flip)
528{
529 struct rds_info_message minfo;
530
531 minfo.seq = be64_to_cpu(inc->i_hdr.h_sequence);
532 minfo.len = be32_to_cpu(inc->i_hdr.h_len);
533
534 if (flip) {
535 minfo.laddr = daddr;
536 minfo.faddr = saddr;
537 minfo.lport = inc->i_hdr.h_dport;
538 minfo.fport = inc->i_hdr.h_sport;
539 } else {
540 minfo.laddr = saddr;
541 minfo.faddr = daddr;
542 minfo.lport = inc->i_hdr.h_sport;
543 minfo.fport = inc->i_hdr.h_dport;
544 }
545
546 rds_info_copy(iter, &minfo, sizeof(minfo));
547}