| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Shared Memory Communications over RDMA (SMC-R) and RoCE |
| * |
| * Socket Closing - normal and abnormal |
| * |
| * Copyright IBM Corp. 2016 |
| * |
| * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> |
| */ |
| |
| #include <linux/workqueue.h> |
| #include <linux/sched/signal.h> |
| |
| #include <net/sock.h> |
| |
| #include "smc.h" |
| #include "smc_tx.h" |
| #include "smc_cdc.h" |
| #include "smc_close.h" |
| |
| #define SMC_CLOSE_WAIT_LISTEN_CLCSOCK_TIME (5 * HZ) |
| |
| static void smc_close_cleanup_listen(struct sock *parent) |
| { |
| struct sock *sk; |
| |
| /* Close non-accepted connections */ |
| while ((sk = smc_accept_dequeue(parent, NULL))) |
| smc_close_non_accepted(sk); |
| } |
| |
| static void smc_close_wait_listen_clcsock(struct smc_sock *smc) |
| { |
| DEFINE_WAIT_FUNC(wait, woken_wake_function); |
| struct sock *sk = &smc->sk; |
| signed long timeout; |
| |
| timeout = SMC_CLOSE_WAIT_LISTEN_CLCSOCK_TIME; |
| add_wait_queue(sk_sleep(sk), &wait); |
| do { |
| release_sock(sk); |
| if (smc->clcsock) |
| timeout = wait_woken(&wait, TASK_UNINTERRUPTIBLE, |
| timeout); |
| sched_annotate_sleep(); |
| lock_sock(sk); |
| if (!smc->clcsock) |
| break; |
| } while (timeout); |
| remove_wait_queue(sk_sleep(sk), &wait); |
| } |
| |
| /* wait for sndbuf data being transmitted */ |
| static void smc_close_stream_wait(struct smc_sock *smc, long timeout) |
| { |
| DEFINE_WAIT_FUNC(wait, woken_wake_function); |
| struct sock *sk = &smc->sk; |
| |
| if (!timeout) |
| return; |
| |
| if (!smc_tx_prepared_sends(&smc->conn)) |
| return; |
| |
| smc->wait_close_tx_prepared = 1; |
| add_wait_queue(sk_sleep(sk), &wait); |
| while (!signal_pending(current) && timeout) { |
| int rc; |
| |
| rc = sk_wait_event(sk, &timeout, |
| !smc_tx_prepared_sends(&smc->conn) || |
| (sk->sk_err == ECONNABORTED) || |
| (sk->sk_err == ECONNRESET), |
| &wait); |
| if (rc) |
| break; |
| } |
| remove_wait_queue(sk_sleep(sk), &wait); |
| smc->wait_close_tx_prepared = 0; |
| } |
| |
| void smc_close_wake_tx_prepared(struct smc_sock *smc) |
| { |
| if (smc->wait_close_tx_prepared) |
| /* wake up socket closing */ |
| smc->sk.sk_state_change(&smc->sk); |
| } |
| |
| static int smc_close_wr(struct smc_connection *conn) |
| { |
| conn->local_tx_ctrl.conn_state_flags.peer_done_writing = 1; |
| |
| return smc_cdc_get_slot_and_msg_send(conn); |
| } |
| |
| static int smc_close_final(struct smc_connection *conn) |
| { |
| if (atomic_read(&conn->bytes_to_rcv)) |
| conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1; |
| else |
| conn->local_tx_ctrl.conn_state_flags.peer_conn_closed = 1; |
| |
| return smc_cdc_get_slot_and_msg_send(conn); |
| } |
| |
| static int smc_close_abort(struct smc_connection *conn) |
| { |
| conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1; |
| |
| return smc_cdc_get_slot_and_msg_send(conn); |
| } |
| |
| /* terminate smc socket abnormally - active abort |
| * link group is terminated, i.e. RDMA communication no longer possible |
| */ |
| static void smc_close_active_abort(struct smc_sock *smc) |
| { |
| struct sock *sk = &smc->sk; |
| |
| struct smc_cdc_conn_state_flags *txflags = |
| &smc->conn.local_tx_ctrl.conn_state_flags; |
| |
| sk->sk_err = ECONNABORTED; |
| if (smc->clcsock && smc->clcsock->sk) { |
| smc->clcsock->sk->sk_err = ECONNABORTED; |
| smc->clcsock->sk->sk_state_change(smc->clcsock->sk); |
| } |
| switch (sk->sk_state) { |
| case SMC_INIT: |
| case SMC_ACTIVE: |
| sk->sk_state = SMC_PEERABORTWAIT; |
| release_sock(sk); |
| cancel_delayed_work_sync(&smc->conn.tx_work); |
| lock_sock(sk); |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_APPCLOSEWAIT1: |
| case SMC_APPCLOSEWAIT2: |
| if (!smc_cdc_rxed_any_close(&smc->conn)) |
| sk->sk_state = SMC_PEERABORTWAIT; |
| else |
| sk->sk_state = SMC_CLOSED; |
| release_sock(sk); |
| cancel_delayed_work_sync(&smc->conn.tx_work); |
| lock_sock(sk); |
| break; |
| case SMC_PEERCLOSEWAIT1: |
| case SMC_PEERCLOSEWAIT2: |
| if (!txflags->peer_conn_closed) { |
| /* just SHUTDOWN_SEND done */ |
| sk->sk_state = SMC_PEERABORTWAIT; |
| } else { |
| sk->sk_state = SMC_CLOSED; |
| } |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_PROCESSABORT: |
| case SMC_APPFINCLOSEWAIT: |
| sk->sk_state = SMC_CLOSED; |
| break; |
| case SMC_PEERFINCLOSEWAIT: |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_PEERABORTWAIT: |
| case SMC_CLOSED: |
| break; |
| } |
| |
| sock_set_flag(sk, SOCK_DEAD); |
| sk->sk_state_change(sk); |
| } |
| |
| static inline bool smc_close_sent_any_close(struct smc_connection *conn) |
| { |
| return conn->local_tx_ctrl.conn_state_flags.peer_conn_abort || |
| conn->local_tx_ctrl.conn_state_flags.peer_conn_closed; |
| } |
| |
| int smc_close_active(struct smc_sock *smc) |
| { |
| struct smc_cdc_conn_state_flags *txflags = |
| &smc->conn.local_tx_ctrl.conn_state_flags; |
| struct smc_connection *conn = &smc->conn; |
| struct sock *sk = &smc->sk; |
| int old_state; |
| long timeout; |
| int rc = 0; |
| |
| timeout = current->flags & PF_EXITING ? |
| 0 : sock_flag(sk, SOCK_LINGER) ? |
| sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT; |
| |
| old_state = sk->sk_state; |
| again: |
| switch (sk->sk_state) { |
| case SMC_INIT: |
| sk->sk_state = SMC_CLOSED; |
| break; |
| case SMC_LISTEN: |
| sk->sk_state = SMC_CLOSED; |
| sk->sk_state_change(sk); /* wake up accept */ |
| if (smc->clcsock && smc->clcsock->sk) { |
| rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR); |
| /* wake up kernel_accept of smc_tcp_listen_worker */ |
| smc->clcsock->sk->sk_data_ready(smc->clcsock->sk); |
| smc_close_wait_listen_clcsock(smc); |
| } |
| smc_close_cleanup_listen(sk); |
| break; |
| case SMC_ACTIVE: |
| smc_close_stream_wait(smc, timeout); |
| release_sock(sk); |
| cancel_delayed_work_sync(&conn->tx_work); |
| lock_sock(sk); |
| if (sk->sk_state == SMC_ACTIVE) { |
| /* send close request */ |
| rc = smc_close_final(conn); |
| if (rc) |
| break; |
| sk->sk_state = SMC_PEERCLOSEWAIT1; |
| } else { |
| /* peer event has changed the state */ |
| goto again; |
| } |
| break; |
| case SMC_APPFINCLOSEWAIT: |
| /* socket already shutdown wr or both (active close) */ |
| if (txflags->peer_done_writing && |
| !smc_close_sent_any_close(conn)) { |
| /* just shutdown wr done, send close request */ |
| rc = smc_close_final(conn); |
| if (rc) |
| break; |
| } |
| sk->sk_state = SMC_CLOSED; |
| break; |
| case SMC_APPCLOSEWAIT1: |
| case SMC_APPCLOSEWAIT2: |
| if (!smc_cdc_rxed_any_close(conn)) |
| smc_close_stream_wait(smc, timeout); |
| release_sock(sk); |
| cancel_delayed_work_sync(&conn->tx_work); |
| lock_sock(sk); |
| if (sk->sk_state != SMC_APPCLOSEWAIT1 && |
| sk->sk_state != SMC_APPCLOSEWAIT2) |
| goto again; |
| /* confirm close from peer */ |
| rc = smc_close_final(conn); |
| if (rc) |
| break; |
| if (smc_cdc_rxed_any_close(conn)) { |
| /* peer has closed the socket already */ |
| sk->sk_state = SMC_CLOSED; |
| sock_put(sk); /* postponed passive closing */ |
| } else { |
| /* peer has just issued a shutdown write */ |
| sk->sk_state = SMC_PEERFINCLOSEWAIT; |
| } |
| break; |
| case SMC_PEERCLOSEWAIT1: |
| case SMC_PEERCLOSEWAIT2: |
| if (txflags->peer_done_writing && |
| !smc_close_sent_any_close(conn)) { |
| /* just shutdown wr done, send close request */ |
| rc = smc_close_final(conn); |
| if (rc) |
| break; |
| } |
| /* peer sending PeerConnectionClosed will cause transition */ |
| break; |
| case SMC_PEERFINCLOSEWAIT: |
| /* peer sending PeerConnectionClosed will cause transition */ |
| break; |
| case SMC_PROCESSABORT: |
| smc_close_abort(conn); |
| sk->sk_state = SMC_CLOSED; |
| break; |
| case SMC_PEERABORTWAIT: |
| case SMC_CLOSED: |
| /* nothing to do, add tracing in future patch */ |
| break; |
| } |
| |
| if (old_state != sk->sk_state) |
| sk->sk_state_change(sk); |
| return rc; |
| } |
| |
| static void smc_close_passive_abort_received(struct smc_sock *smc) |
| { |
| struct smc_cdc_conn_state_flags *txflags = |
| &smc->conn.local_tx_ctrl.conn_state_flags; |
| struct sock *sk = &smc->sk; |
| |
| switch (sk->sk_state) { |
| case SMC_INIT: |
| case SMC_ACTIVE: |
| case SMC_APPCLOSEWAIT1: |
| sk->sk_state = SMC_PROCESSABORT; |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_APPFINCLOSEWAIT: |
| sk->sk_state = SMC_PROCESSABORT; |
| break; |
| case SMC_PEERCLOSEWAIT1: |
| case SMC_PEERCLOSEWAIT2: |
| if (txflags->peer_done_writing && |
| !smc_close_sent_any_close(&smc->conn)) |
| /* just shutdown, but not yet closed locally */ |
| sk->sk_state = SMC_PROCESSABORT; |
| else |
| sk->sk_state = SMC_CLOSED; |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_APPCLOSEWAIT2: |
| case SMC_PEERFINCLOSEWAIT: |
| sk->sk_state = SMC_CLOSED; |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_PEERABORTWAIT: |
| sk->sk_state = SMC_CLOSED; |
| break; |
| case SMC_PROCESSABORT: |
| /* nothing to do, add tracing in future patch */ |
| break; |
| } |
| } |
| |
| /* Either some kind of closing has been received: peer_conn_closed, |
| * peer_conn_abort, or peer_done_writing |
| * or the link group of the connection terminates abnormally. |
| */ |
| static void smc_close_passive_work(struct work_struct *work) |
| { |
| struct smc_connection *conn = container_of(work, |
| struct smc_connection, |
| close_work); |
| struct smc_sock *smc = container_of(conn, struct smc_sock, conn); |
| struct smc_cdc_conn_state_flags *rxflags; |
| struct sock *sk = &smc->sk; |
| int old_state; |
| |
| lock_sock(sk); |
| old_state = sk->sk_state; |
| |
| if (!conn->alert_token_local) { |
| /* abnormal termination */ |
| smc_close_active_abort(smc); |
| goto wakeup; |
| } |
| |
| rxflags = &conn->local_rx_ctrl.conn_state_flags; |
| if (rxflags->peer_conn_abort) { |
| /* peer has not received all data */ |
| smc_close_passive_abort_received(smc); |
| release_sock(&smc->sk); |
| cancel_delayed_work_sync(&conn->tx_work); |
| lock_sock(&smc->sk); |
| goto wakeup; |
| } |
| |
| switch (sk->sk_state) { |
| case SMC_INIT: |
| if (atomic_read(&conn->bytes_to_rcv) || |
| (rxflags->peer_done_writing && |
| !smc_cdc_rxed_any_close(conn))) { |
| sk->sk_state = SMC_APPCLOSEWAIT1; |
| } else { |
| sk->sk_state = SMC_CLOSED; |
| sock_put(sk); /* passive closing */ |
| } |
| break; |
| case SMC_ACTIVE: |
| sk->sk_state = SMC_APPCLOSEWAIT1; |
| /* postpone sock_put() for passive closing to cover |
| * received SEND_SHUTDOWN as well |
| */ |
| break; |
| case SMC_PEERCLOSEWAIT1: |
| if (rxflags->peer_done_writing) |
| sk->sk_state = SMC_PEERCLOSEWAIT2; |
| /* fall through */ |
| /* to check for closing */ |
| case SMC_PEERCLOSEWAIT2: |
| if (!smc_cdc_rxed_any_close(conn)) |
| break; |
| if (sock_flag(sk, SOCK_DEAD) && |
| smc_close_sent_any_close(conn)) { |
| /* smc_release has already been called locally */ |
| sk->sk_state = SMC_CLOSED; |
| } else { |
| /* just shutdown, but not yet closed locally */ |
| sk->sk_state = SMC_APPFINCLOSEWAIT; |
| } |
| sock_put(sk); /* passive closing */ |
| break; |
| case SMC_PEERFINCLOSEWAIT: |
| if (smc_cdc_rxed_any_close(conn)) { |
| sk->sk_state = SMC_CLOSED; |
| sock_put(sk); /* passive closing */ |
| } |
| break; |
| case SMC_APPCLOSEWAIT1: |
| case SMC_APPCLOSEWAIT2: |
| /* postpone sock_put() for passive closing to cover |
| * received SEND_SHUTDOWN as well |
| */ |
| break; |
| case SMC_APPFINCLOSEWAIT: |
| case SMC_PEERABORTWAIT: |
| case SMC_PROCESSABORT: |
| case SMC_CLOSED: |
| /* nothing to do, add tracing in future patch */ |
| break; |
| } |
| |
| wakeup: |
| sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */ |
| sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */ |
| |
| if (old_state != sk->sk_state) { |
| sk->sk_state_change(sk); |
| if ((sk->sk_state == SMC_CLOSED) && |
| (sock_flag(sk, SOCK_DEAD) || !sk->sk_socket)) |
| smc_conn_free(conn); |
| } |
| release_sock(sk); |
| sock_put(sk); /* sock_hold done by schedulers of close_work */ |
| } |
| |
| int smc_close_shutdown_write(struct smc_sock *smc) |
| { |
| struct smc_connection *conn = &smc->conn; |
| struct sock *sk = &smc->sk; |
| int old_state; |
| long timeout; |
| int rc = 0; |
| |
| timeout = current->flags & PF_EXITING ? |
| 0 : sock_flag(sk, SOCK_LINGER) ? |
| sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT; |
| |
| old_state = sk->sk_state; |
| again: |
| switch (sk->sk_state) { |
| case SMC_ACTIVE: |
| smc_close_stream_wait(smc, timeout); |
| release_sock(sk); |
| cancel_delayed_work_sync(&conn->tx_work); |
| lock_sock(sk); |
| if (sk->sk_state != SMC_ACTIVE) |
| goto again; |
| /* send close wr request */ |
| rc = smc_close_wr(conn); |
| if (rc) |
| break; |
| sk->sk_state = SMC_PEERCLOSEWAIT1; |
| break; |
| case SMC_APPCLOSEWAIT1: |
| /* passive close */ |
| if (!smc_cdc_rxed_any_close(conn)) |
| smc_close_stream_wait(smc, timeout); |
| release_sock(sk); |
| cancel_delayed_work_sync(&conn->tx_work); |
| lock_sock(sk); |
| if (sk->sk_state != SMC_APPCLOSEWAIT1) |
| goto again; |
| /* confirm close from peer */ |
| rc = smc_close_wr(conn); |
| if (rc) |
| break; |
| sk->sk_state = SMC_APPCLOSEWAIT2; |
| break; |
| case SMC_APPCLOSEWAIT2: |
| case SMC_PEERFINCLOSEWAIT: |
| case SMC_PEERCLOSEWAIT1: |
| case SMC_PEERCLOSEWAIT2: |
| case SMC_APPFINCLOSEWAIT: |
| case SMC_PROCESSABORT: |
| case SMC_PEERABORTWAIT: |
| /* nothing to do, add tracing in future patch */ |
| break; |
| } |
| |
| if (old_state != sk->sk_state) |
| sk->sk_state_change(sk); |
| return rc; |
| } |
| |
| /* Initialize close properties on connection establishment. */ |
| void smc_close_init(struct smc_sock *smc) |
| { |
| INIT_WORK(&smc->conn.close_work, smc_close_passive_work); |
| } |