1 // SPDX-License-Identifier: GPL-2.0
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
5 * Socket Closing - normal and abnormal
7 * Copyright IBM Corp. 2016
9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
12 #include <linux/workqueue.h>
13 #include <linux/sched/signal.h>
20 #include "smc_close.h"
22 #define SMC_CLOSE_WAIT_LISTEN_CLCSOCK_TIME (5 * HZ)
24 static void smc_close_cleanup_listen(struct sock *parent)
28 /* Close non-accepted connections */
29 while ((sk = smc_accept_dequeue(parent, NULL)))
30 smc_close_non_accepted(sk);
33 /* wait for sndbuf data being transmitted */
34 static void smc_close_stream_wait(struct smc_sock *smc, long timeout)
36 DEFINE_WAIT_FUNC(wait, woken_wake_function);
37 struct sock *sk = &smc->sk;
42 if (!smc_tx_prepared_sends(&smc->conn))
45 smc->wait_close_tx_prepared = 1;
46 add_wait_queue(sk_sleep(sk), &wait);
47 while (!signal_pending(current) && timeout) {
50 rc = sk_wait_event(sk, &timeout,
51 !smc_tx_prepared_sends(&smc->conn) ||
52 (sk->sk_err == ECONNABORTED) ||
53 (sk->sk_err == ECONNRESET),
58 remove_wait_queue(sk_sleep(sk), &wait);
59 smc->wait_close_tx_prepared = 0;
62 void smc_close_wake_tx_prepared(struct smc_sock *smc)
64 if (smc->wait_close_tx_prepared)
65 /* wake up socket closing */
66 smc->sk.sk_state_change(&smc->sk);
69 static int smc_close_wr(struct smc_connection *conn)
71 conn->local_tx_ctrl.conn_state_flags.peer_done_writing = 1;
73 return smc_cdc_get_slot_and_msg_send(conn);
76 static int smc_close_final(struct smc_connection *conn)
78 if (atomic_read(&conn->bytes_to_rcv))
79 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
81 conn->local_tx_ctrl.conn_state_flags.peer_conn_closed = 1;
83 return smc_cdc_get_slot_and_msg_send(conn);
86 static int smc_close_abort(struct smc_connection *conn)
88 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
90 return smc_cdc_get_slot_and_msg_send(conn);
93 /* terminate smc socket abnormally - active abort
94 * link group is terminated, i.e. RDMA communication no longer possible
96 static void smc_close_active_abort(struct smc_sock *smc)
98 struct sock *sk = &smc->sk;
100 struct smc_cdc_conn_state_flags *txflags =
101 &smc->conn.local_tx_ctrl.conn_state_flags;
103 sk->sk_err = ECONNABORTED;
104 if (smc->clcsock && smc->clcsock->sk) {
105 smc->clcsock->sk->sk_err = ECONNABORTED;
106 smc->clcsock->sk->sk_state_change(smc->clcsock->sk);
108 switch (sk->sk_state) {
111 sk->sk_state = SMC_PEERABORTWAIT;
113 cancel_delayed_work_sync(&smc->conn.tx_work);
115 sock_put(sk); /* passive closing */
117 case SMC_APPCLOSEWAIT1:
118 case SMC_APPCLOSEWAIT2:
119 if (!smc_cdc_rxed_any_close(&smc->conn))
120 sk->sk_state = SMC_PEERABORTWAIT;
122 sk->sk_state = SMC_CLOSED;
124 cancel_delayed_work_sync(&smc->conn.tx_work);
127 case SMC_PEERCLOSEWAIT1:
128 case SMC_PEERCLOSEWAIT2:
129 if (!txflags->peer_conn_closed) {
130 /* just SHUTDOWN_SEND done */
131 sk->sk_state = SMC_PEERABORTWAIT;
133 sk->sk_state = SMC_CLOSED;
135 sock_put(sk); /* passive closing */
137 case SMC_PROCESSABORT:
138 case SMC_APPFINCLOSEWAIT:
139 sk->sk_state = SMC_CLOSED;
141 case SMC_PEERFINCLOSEWAIT:
142 sock_put(sk); /* passive closing */
144 case SMC_PEERABORTWAIT:
149 sock_set_flag(sk, SOCK_DEAD);
150 sk->sk_state_change(sk);
153 static inline bool smc_close_sent_any_close(struct smc_connection *conn)
155 return conn->local_tx_ctrl.conn_state_flags.peer_conn_abort ||
156 conn->local_tx_ctrl.conn_state_flags.peer_conn_closed;
159 int smc_close_active(struct smc_sock *smc)
161 struct smc_cdc_conn_state_flags *txflags =
162 &smc->conn.local_tx_ctrl.conn_state_flags;
163 struct smc_connection *conn = &smc->conn;
164 struct sock *sk = &smc->sk;
169 timeout = current->flags & PF_EXITING ?
170 0 : sock_flag(sk, SOCK_LINGER) ?
171 sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
173 old_state = sk->sk_state;
175 switch (sk->sk_state) {
177 sk->sk_state = SMC_CLOSED;
180 sk->sk_state = SMC_CLOSED;
181 sk->sk_state_change(sk); /* wake up accept */
182 if (smc->clcsock && smc->clcsock->sk) {
183 rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
184 /* wake up kernel_accept of smc_tcp_listen_worker */
185 smc->clcsock->sk->sk_data_ready(smc->clcsock->sk);
187 smc_close_cleanup_listen(sk);
189 flush_work(&smc->tcp_listen_work);
193 smc_close_stream_wait(smc, timeout);
195 cancel_delayed_work_sync(&conn->tx_work);
197 if (sk->sk_state == SMC_ACTIVE) {
198 /* send close request */
199 rc = smc_close_final(conn);
202 sk->sk_state = SMC_PEERCLOSEWAIT1;
204 /* peer event has changed the state */
208 case SMC_APPFINCLOSEWAIT:
209 /* socket already shutdown wr or both (active close) */
210 if (txflags->peer_done_writing &&
211 !smc_close_sent_any_close(conn)) {
212 /* just shutdown wr done, send close request */
213 rc = smc_close_final(conn);
217 sk->sk_state = SMC_CLOSED;
219 case SMC_APPCLOSEWAIT1:
220 case SMC_APPCLOSEWAIT2:
221 if (!smc_cdc_rxed_any_close(conn))
222 smc_close_stream_wait(smc, timeout);
224 cancel_delayed_work_sync(&conn->tx_work);
226 if (sk->sk_state != SMC_APPCLOSEWAIT1 &&
227 sk->sk_state != SMC_APPCLOSEWAIT2)
229 /* confirm close from peer */
230 rc = smc_close_final(conn);
233 if (smc_cdc_rxed_any_close(conn)) {
234 /* peer has closed the socket already */
235 sk->sk_state = SMC_CLOSED;
236 sock_put(sk); /* postponed passive closing */
238 /* peer has just issued a shutdown write */
239 sk->sk_state = SMC_PEERFINCLOSEWAIT;
242 case SMC_PEERCLOSEWAIT1:
243 case SMC_PEERCLOSEWAIT2:
244 if (txflags->peer_done_writing &&
245 !smc_close_sent_any_close(conn)) {
246 /* just shutdown wr done, send close request */
247 rc = smc_close_final(conn);
251 /* peer sending PeerConnectionClosed will cause transition */
253 case SMC_PEERFINCLOSEWAIT:
254 /* peer sending PeerConnectionClosed will cause transition */
256 case SMC_PROCESSABORT:
257 smc_close_abort(conn);
258 sk->sk_state = SMC_CLOSED;
260 case SMC_PEERABORTWAIT:
262 /* nothing to do, add tracing in future patch */
266 if (old_state != sk->sk_state)
267 sk->sk_state_change(sk);
271 static void smc_close_passive_abort_received(struct smc_sock *smc)
273 struct smc_cdc_conn_state_flags *txflags =
274 &smc->conn.local_tx_ctrl.conn_state_flags;
275 struct sock *sk = &smc->sk;
277 switch (sk->sk_state) {
280 case SMC_APPCLOSEWAIT1:
281 sk->sk_state = SMC_PROCESSABORT;
282 sock_put(sk); /* passive closing */
284 case SMC_APPFINCLOSEWAIT:
285 sk->sk_state = SMC_PROCESSABORT;
287 case SMC_PEERCLOSEWAIT1:
288 case SMC_PEERCLOSEWAIT2:
289 if (txflags->peer_done_writing &&
290 !smc_close_sent_any_close(&smc->conn))
291 /* just shutdown, but not yet closed locally */
292 sk->sk_state = SMC_PROCESSABORT;
294 sk->sk_state = SMC_CLOSED;
295 sock_put(sk); /* passive closing */
297 case SMC_APPCLOSEWAIT2:
298 case SMC_PEERFINCLOSEWAIT:
299 sk->sk_state = SMC_CLOSED;
300 sock_put(sk); /* passive closing */
302 case SMC_PEERABORTWAIT:
303 sk->sk_state = SMC_CLOSED;
305 case SMC_PROCESSABORT:
306 /* nothing to do, add tracing in future patch */
311 /* Either some kind of closing has been received: peer_conn_closed,
312 * peer_conn_abort, or peer_done_writing
313 * or the link group of the connection terminates abnormally.
315 static void smc_close_passive_work(struct work_struct *work)
317 struct smc_connection *conn = container_of(work,
318 struct smc_connection,
320 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
321 struct smc_cdc_conn_state_flags *rxflags;
322 struct sock *sk = &smc->sk;
326 old_state = sk->sk_state;
328 if (!conn->alert_token_local) {
329 /* abnormal termination */
330 smc_close_active_abort(smc);
334 rxflags = &conn->local_rx_ctrl.conn_state_flags;
335 if (rxflags->peer_conn_abort) {
336 /* peer has not received all data */
337 smc_close_passive_abort_received(smc);
338 release_sock(&smc->sk);
339 cancel_delayed_work_sync(&conn->tx_work);
344 switch (sk->sk_state) {
346 if (atomic_read(&conn->bytes_to_rcv) ||
347 (rxflags->peer_done_writing &&
348 !smc_cdc_rxed_any_close(conn))) {
349 sk->sk_state = SMC_APPCLOSEWAIT1;
351 sk->sk_state = SMC_CLOSED;
352 sock_put(sk); /* passive closing */
356 sk->sk_state = SMC_APPCLOSEWAIT1;
357 /* postpone sock_put() for passive closing to cover
358 * received SEND_SHUTDOWN as well
361 case SMC_PEERCLOSEWAIT1:
362 if (rxflags->peer_done_writing)
363 sk->sk_state = SMC_PEERCLOSEWAIT2;
365 /* to check for closing */
366 case SMC_PEERCLOSEWAIT2:
367 if (!smc_cdc_rxed_any_close(conn))
369 if (sock_flag(sk, SOCK_DEAD) &&
370 smc_close_sent_any_close(conn)) {
371 /* smc_release has already been called locally */
372 sk->sk_state = SMC_CLOSED;
374 /* just shutdown, but not yet closed locally */
375 sk->sk_state = SMC_APPFINCLOSEWAIT;
377 sock_put(sk); /* passive closing */
379 case SMC_PEERFINCLOSEWAIT:
380 if (smc_cdc_rxed_any_close(conn)) {
381 sk->sk_state = SMC_CLOSED;
382 sock_put(sk); /* passive closing */
385 case SMC_APPCLOSEWAIT1:
386 case SMC_APPCLOSEWAIT2:
387 /* postpone sock_put() for passive closing to cover
388 * received SEND_SHUTDOWN as well
391 case SMC_APPFINCLOSEWAIT:
392 case SMC_PEERABORTWAIT:
393 case SMC_PROCESSABORT:
395 /* nothing to do, add tracing in future patch */
400 sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */
401 sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */
403 if (old_state != sk->sk_state) {
404 sk->sk_state_change(sk);
405 if ((sk->sk_state == SMC_CLOSED) &&
406 (sock_flag(sk, SOCK_DEAD) || !sk->sk_socket))
410 sock_put(sk); /* sock_hold done by schedulers of close_work */
413 int smc_close_shutdown_write(struct smc_sock *smc)
415 struct smc_connection *conn = &smc->conn;
416 struct sock *sk = &smc->sk;
421 timeout = current->flags & PF_EXITING ?
422 0 : sock_flag(sk, SOCK_LINGER) ?
423 sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
425 old_state = sk->sk_state;
427 switch (sk->sk_state) {
429 smc_close_stream_wait(smc, timeout);
431 cancel_delayed_work_sync(&conn->tx_work);
433 if (sk->sk_state != SMC_ACTIVE)
435 /* send close wr request */
436 rc = smc_close_wr(conn);
439 sk->sk_state = SMC_PEERCLOSEWAIT1;
441 case SMC_APPCLOSEWAIT1:
443 if (!smc_cdc_rxed_any_close(conn))
444 smc_close_stream_wait(smc, timeout);
446 cancel_delayed_work_sync(&conn->tx_work);
448 if (sk->sk_state != SMC_APPCLOSEWAIT1)
450 /* confirm close from peer */
451 rc = smc_close_wr(conn);
454 sk->sk_state = SMC_APPCLOSEWAIT2;
456 case SMC_APPCLOSEWAIT2:
457 case SMC_PEERFINCLOSEWAIT:
458 case SMC_PEERCLOSEWAIT1:
459 case SMC_PEERCLOSEWAIT2:
460 case SMC_APPFINCLOSEWAIT:
461 case SMC_PROCESSABORT:
462 case SMC_PEERABORTWAIT:
463 /* nothing to do, add tracing in future patch */
467 if (old_state != sk->sk_state)
468 sk->sk_state_change(sk);
472 /* Initialize close properties on connection establishment. */
473 void smc_close_init(struct smc_sock *smc)
475 INIT_WORK(&smc->conn.close_work, smc_close_passive_work);