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 if (sk->sk_state != SMC_INIT && smc->clcsock && smc->clcsock->sk) {
104 sk->sk_err = ECONNABORTED;
105 if (smc->clcsock && smc->clcsock->sk) {
106 smc->clcsock->sk->sk_err = ECONNABORTED;
107 smc->clcsock->sk->sk_state_change(smc->clcsock->sk);
110 switch (sk->sk_state) {
112 sk->sk_state = SMC_PEERABORTWAIT;
114 cancel_delayed_work_sync(&smc->conn.tx_work);
116 sock_put(sk); /* passive closing */
118 case SMC_APPCLOSEWAIT1:
119 case SMC_APPCLOSEWAIT2:
120 if (!smc_cdc_rxed_any_close(&smc->conn))
121 sk->sk_state = SMC_PEERABORTWAIT;
123 sk->sk_state = SMC_CLOSED;
125 cancel_delayed_work_sync(&smc->conn.tx_work);
128 case SMC_PEERCLOSEWAIT1:
129 case SMC_PEERCLOSEWAIT2:
130 if (!txflags->peer_conn_closed) {
131 /* just SHUTDOWN_SEND done */
132 sk->sk_state = SMC_PEERABORTWAIT;
134 sk->sk_state = SMC_CLOSED;
136 sock_put(sk); /* passive closing */
138 case SMC_PROCESSABORT:
139 case SMC_APPFINCLOSEWAIT:
140 sk->sk_state = SMC_CLOSED;
142 case SMC_PEERFINCLOSEWAIT:
143 sock_put(sk); /* passive closing */
146 case SMC_PEERABORTWAIT:
151 sock_set_flag(sk, SOCK_DEAD);
152 sk->sk_state_change(sk);
155 static inline bool smc_close_sent_any_close(struct smc_connection *conn)
157 return conn->local_tx_ctrl.conn_state_flags.peer_conn_abort ||
158 conn->local_tx_ctrl.conn_state_flags.peer_conn_closed;
161 int smc_close_active(struct smc_sock *smc)
163 struct smc_cdc_conn_state_flags *txflags =
164 &smc->conn.local_tx_ctrl.conn_state_flags;
165 struct smc_connection *conn = &smc->conn;
166 struct sock *sk = &smc->sk;
171 timeout = current->flags & PF_EXITING ?
172 0 : sock_flag(sk, SOCK_LINGER) ?
173 sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
175 old_state = sk->sk_state;
177 switch (sk->sk_state) {
179 sk->sk_state = SMC_CLOSED;
182 sk->sk_state = SMC_CLOSED;
183 sk->sk_state_change(sk); /* wake up accept */
184 if (smc->clcsock && smc->clcsock->sk) {
185 rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
186 /* wake up kernel_accept of smc_tcp_listen_worker */
187 smc->clcsock->sk->sk_data_ready(smc->clcsock->sk);
189 smc_close_cleanup_listen(sk);
191 flush_work(&smc->tcp_listen_work);
195 smc_close_stream_wait(smc, timeout);
197 cancel_delayed_work_sync(&conn->tx_work);
199 if (sk->sk_state == SMC_ACTIVE) {
200 /* send close request */
201 rc = smc_close_final(conn);
204 sk->sk_state = SMC_PEERCLOSEWAIT1;
206 /* peer event has changed the state */
210 case SMC_APPFINCLOSEWAIT:
211 /* socket already shutdown wr or both (active close) */
212 if (txflags->peer_done_writing &&
213 !smc_close_sent_any_close(conn)) {
214 /* just shutdown wr done, send close request */
215 rc = smc_close_final(conn);
219 sk->sk_state = SMC_CLOSED;
221 case SMC_APPCLOSEWAIT1:
222 case SMC_APPCLOSEWAIT2:
223 if (!smc_cdc_rxed_any_close(conn))
224 smc_close_stream_wait(smc, timeout);
226 cancel_delayed_work_sync(&conn->tx_work);
228 if (sk->sk_state != SMC_APPCLOSEWAIT1 &&
229 sk->sk_state != SMC_APPCLOSEWAIT2)
231 /* confirm close from peer */
232 rc = smc_close_final(conn);
235 if (smc_cdc_rxed_any_close(conn)) {
236 /* peer has closed the socket already */
237 sk->sk_state = SMC_CLOSED;
238 sock_put(sk); /* postponed passive closing */
240 /* peer has just issued a shutdown write */
241 sk->sk_state = SMC_PEERFINCLOSEWAIT;
244 case SMC_PEERCLOSEWAIT1:
245 case SMC_PEERCLOSEWAIT2:
246 if (txflags->peer_done_writing &&
247 !smc_close_sent_any_close(conn)) {
248 /* just shutdown wr done, send close request */
249 rc = smc_close_final(conn);
253 /* peer sending PeerConnectionClosed will cause transition */
255 case SMC_PEERFINCLOSEWAIT:
256 /* peer sending PeerConnectionClosed will cause transition */
258 case SMC_PROCESSABORT:
259 smc_close_abort(conn);
260 sk->sk_state = SMC_CLOSED;
262 case SMC_PEERABORTWAIT:
264 /* nothing to do, add tracing in future patch */
268 if (old_state != sk->sk_state)
269 sk->sk_state_change(sk);
273 static void smc_close_passive_abort_received(struct smc_sock *smc)
275 struct smc_cdc_conn_state_flags *txflags =
276 &smc->conn.local_tx_ctrl.conn_state_flags;
277 struct sock *sk = &smc->sk;
279 switch (sk->sk_state) {
282 case SMC_APPCLOSEWAIT1:
283 sk->sk_state = SMC_PROCESSABORT;
284 sock_put(sk); /* passive closing */
286 case SMC_APPFINCLOSEWAIT:
287 sk->sk_state = SMC_PROCESSABORT;
289 case SMC_PEERCLOSEWAIT1:
290 case SMC_PEERCLOSEWAIT2:
291 if (txflags->peer_done_writing &&
292 !smc_close_sent_any_close(&smc->conn))
293 /* just shutdown, but not yet closed locally */
294 sk->sk_state = SMC_PROCESSABORT;
296 sk->sk_state = SMC_CLOSED;
297 sock_put(sk); /* passive closing */
299 case SMC_APPCLOSEWAIT2:
300 case SMC_PEERFINCLOSEWAIT:
301 sk->sk_state = SMC_CLOSED;
302 sock_put(sk); /* passive closing */
304 case SMC_PEERABORTWAIT:
305 sk->sk_state = SMC_CLOSED;
307 case SMC_PROCESSABORT:
308 /* nothing to do, add tracing in future patch */
313 /* Either some kind of closing has been received: peer_conn_closed,
314 * peer_conn_abort, or peer_done_writing
315 * or the link group of the connection terminates abnormally.
317 static void smc_close_passive_work(struct work_struct *work)
319 struct smc_connection *conn = container_of(work,
320 struct smc_connection,
322 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
323 struct smc_cdc_conn_state_flags *rxflags;
324 struct sock *sk = &smc->sk;
328 old_state = sk->sk_state;
330 if (!conn->alert_token_local) {
331 /* abnormal termination */
332 smc_close_active_abort(smc);
336 rxflags = &conn->local_rx_ctrl.conn_state_flags;
337 if (rxflags->peer_conn_abort) {
338 /* peer has not received all data */
339 smc_close_passive_abort_received(smc);
340 release_sock(&smc->sk);
341 cancel_delayed_work_sync(&conn->tx_work);
346 switch (sk->sk_state) {
348 if (atomic_read(&conn->bytes_to_rcv) ||
349 (rxflags->peer_done_writing &&
350 !smc_cdc_rxed_any_close(conn))) {
351 sk->sk_state = SMC_APPCLOSEWAIT1;
353 sk->sk_state = SMC_CLOSED;
354 sock_put(sk); /* passive closing */
358 sk->sk_state = SMC_APPCLOSEWAIT1;
359 /* postpone sock_put() for passive closing to cover
360 * received SEND_SHUTDOWN as well
363 case SMC_PEERCLOSEWAIT1:
364 if (rxflags->peer_done_writing)
365 sk->sk_state = SMC_PEERCLOSEWAIT2;
367 /* to check for closing */
368 case SMC_PEERCLOSEWAIT2:
369 if (!smc_cdc_rxed_any_close(conn))
371 if (sock_flag(sk, SOCK_DEAD) &&
372 smc_close_sent_any_close(conn)) {
373 /* smc_release has already been called locally */
374 sk->sk_state = SMC_CLOSED;
376 /* just shutdown, but not yet closed locally */
377 sk->sk_state = SMC_APPFINCLOSEWAIT;
379 sock_put(sk); /* passive closing */
381 case SMC_PEERFINCLOSEWAIT:
382 if (smc_cdc_rxed_any_close(conn)) {
383 sk->sk_state = SMC_CLOSED;
384 sock_put(sk); /* passive closing */
387 case SMC_APPCLOSEWAIT1:
388 case SMC_APPCLOSEWAIT2:
389 /* postpone sock_put() for passive closing to cover
390 * received SEND_SHUTDOWN as well
393 case SMC_APPFINCLOSEWAIT:
394 case SMC_PEERABORTWAIT:
395 case SMC_PROCESSABORT:
397 /* nothing to do, add tracing in future patch */
402 sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */
403 sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */
405 if (old_state != sk->sk_state) {
406 sk->sk_state_change(sk);
407 if ((sk->sk_state == SMC_CLOSED) &&
408 (sock_flag(sk, SOCK_DEAD) || !sk->sk_socket))
412 sock_put(sk); /* sock_hold done by schedulers of close_work */
415 int smc_close_shutdown_write(struct smc_sock *smc)
417 struct smc_connection *conn = &smc->conn;
418 struct sock *sk = &smc->sk;
423 timeout = current->flags & PF_EXITING ?
424 0 : sock_flag(sk, SOCK_LINGER) ?
425 sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
427 old_state = sk->sk_state;
429 switch (sk->sk_state) {
431 smc_close_stream_wait(smc, timeout);
433 cancel_delayed_work_sync(&conn->tx_work);
435 if (sk->sk_state != SMC_ACTIVE)
437 /* send close wr request */
438 rc = smc_close_wr(conn);
441 sk->sk_state = SMC_PEERCLOSEWAIT1;
443 case SMC_APPCLOSEWAIT1:
445 if (!smc_cdc_rxed_any_close(conn))
446 smc_close_stream_wait(smc, timeout);
448 cancel_delayed_work_sync(&conn->tx_work);
450 if (sk->sk_state != SMC_APPCLOSEWAIT1)
452 /* confirm close from peer */
453 rc = smc_close_wr(conn);
456 sk->sk_state = SMC_APPCLOSEWAIT2;
458 case SMC_APPCLOSEWAIT2:
459 case SMC_PEERFINCLOSEWAIT:
460 case SMC_PEERCLOSEWAIT1:
461 case SMC_PEERCLOSEWAIT2:
462 case SMC_APPFINCLOSEWAIT:
463 case SMC_PROCESSABORT:
464 case SMC_PEERABORTWAIT:
465 /* nothing to do, add tracing in future patch */
469 if (old_state != sk->sk_state)
470 sk->sk_state_change(sk);
474 /* Initialize close properties on connection establishment. */
475 void smc_close_init(struct smc_sock *smc)
477 INIT_WORK(&smc->conn.close_work, smc_close_passive_work);