diff options
Diffstat (limited to 'net/smc/smc_close.c')
| -rw-r--r-- | net/smc/smc_close.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c new file mode 100644 index 000000000000..d70c05b57021 --- /dev/null +++ b/net/smc/smc_close.c @@ -0,0 +1,441 @@ +/* + * 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 <net/sock.h> + +#include "smc.h" +#include "smc_tx.h" +#include "smc_cdc.h" +#include "smc_close.h" + +#define SMC_CLOSE_WAIT_TX_PENDS_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_tx_pends(struct smc_sock *smc) +{ + DEFINE_WAIT_FUNC(wait, woken_wake_function); + struct sock *sk = &smc->sk; + signed long timeout; + + timeout = SMC_CLOSE_WAIT_TX_PENDS_TIME; + add_wait_queue(sk_sleep(sk), &wait); + while (!signal_pending(current) && timeout) { + int rc; + + rc = sk_wait_event(sk, &timeout, + !smc_cdc_tx_has_pending(&smc->conn), + &wait); + if (rc) + break; + } + 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 + * RDMA communication no longer possible + */ +void smc_close_active_abort(struct smc_sock *smc) +{ + struct smc_cdc_conn_state_flags *txflags = + &smc->conn.local_tx_ctrl.conn_state_flags; + + bh_lock_sock(&smc->sk); + smc->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 (smc->sk.sk_state) { + case SMC_INIT: + smc->sk.sk_state = SMC_PEERABORTWAIT; + break; + case SMC_APPCLOSEWAIT1: + case SMC_APPCLOSEWAIT2: + txflags->peer_conn_abort = 1; + sock_release(smc->clcsock); + if (!smc_cdc_rxed_any_close(&smc->conn)) + smc->sk.sk_state = SMC_PEERABORTWAIT; + else + smc->sk.sk_state = SMC_CLOSED; + break; + case SMC_PEERCLOSEWAIT1: + case SMC_PEERCLOSEWAIT2: + if (!txflags->peer_conn_closed) { + smc->sk.sk_state = SMC_PEERABORTWAIT; + txflags->peer_conn_abort = 1; + sock_release(smc->clcsock); + } else { + smc->sk.sk_state = SMC_CLOSED; + } + break; + case SMC_PROCESSABORT: + case SMC_APPFINCLOSEWAIT: + if (!txflags->peer_conn_closed) { + txflags->peer_conn_abort = 1; + sock_release(smc->clcsock); + } + smc->sk.sk_state = SMC_CLOSED; + break; + case SMC_PEERFINCLOSEWAIT: + case SMC_PEERABORTWAIT: + case SMC_CLOSED: + break; + } + + sock_set_flag(&smc->sk, SOCK_DEAD); + bh_unlock_sock(&smc->sk); + smc->sk.sk_state_change(&smc->sk); +} + +int smc_close_active(struct smc_sock *smc) +{ + struct smc_cdc_conn_state_flags *txflags = + &smc->conn.local_tx_ctrl.conn_state_flags; + long timeout = SMC_MAX_STREAM_WAIT_TIMEOUT; + struct smc_connection *conn = &smc->conn; + struct sock *sk = &smc->sk; + int old_state; + int rc = 0; + + if (sock_flag(sk, SOCK_LINGER) && + !(current->flags & PF_EXITING)) + timeout = sk->sk_lingertime; + +again: + old_state = sk->sk_state; + switch (old_state) { + case SMC_INIT: + sk->sk_state = SMC_CLOSED; + if (smc->smc_listen_work.func) + flush_work(&smc->smc_listen_work); + sock_put(sk); + 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); + } + release_sock(sk); + smc_close_cleanup_listen(sk); + flush_work(&smc->tcp_listen_work); + lock_sock(sk); + break; + case SMC_ACTIVE: + smc_close_stream_wait(smc, timeout); + release_sock(sk); + cancel_work_sync(&conn->tx_work); + lock_sock(sk); + if (sk->sk_state == SMC_ACTIVE) { + /* send close request */ + rc = smc_close_final(conn); + 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 && + !txflags->peer_conn_closed) { + /* just shutdown wr done, send close request */ + rc = smc_close_final(conn); + } + sk->sk_state = SMC_CLOSED; + smc_close_wait_tx_pends(smc); + break; + case SMC_APPCLOSEWAIT1: + case SMC_APPCLOSEWAIT2: + if (!smc_cdc_rxed_any_close(conn)) + smc_close_stream_wait(smc, timeout); + release_sock(sk); + cancel_work_sync(&conn->tx_work); + lock_sock(sk); + if (sk->sk_err != ECONNABORTED) { + /* 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; + else + /* peer has just issued a shutdown write */ + sk->sk_state = SMC_PEERFINCLOSEWAIT; + smc_close_wait_tx_pends(smc); + break; + case SMC_PEERCLOSEWAIT1: + case SMC_PEERCLOSEWAIT2: + case SMC_PEERFINCLOSEWAIT: + /* peer sending PeerConnectionClosed will cause transition */ + break; + case SMC_PROCESSABORT: + cancel_work_sync(&conn->tx_work); + smc_close_abort(conn); + sk->sk_state = SMC_CLOSED; + smc_close_wait_tx_pends(smc); + 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(&smc->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_ACTIVE: + case SMC_APPFINCLOSEWAIT: + case SMC_APPCLOSEWAIT1: + case SMC_APPCLOSEWAIT2: + smc_close_abort(&smc->conn); + sk->sk_state = SMC_PROCESSABORT; + break; + case SMC_PEERCLOSEWAIT1: + case SMC_PEERCLOSEWAIT2: + if (txflags->peer_done_writing && + !txflags->peer_conn_closed) { + /* just shutdown, but not yet closed locally */ + smc_close_abort(&smc->conn); + sk->sk_state = SMC_PROCESSABORT; + } else { + sk->sk_state = SMC_CLOSED; + } + break; + case SMC_PEERFINCLOSEWAIT: + case SMC_PEERABORTWAIT: + sk->sk_state = SMC_CLOSED; + break; + case SMC_INIT: + case SMC_PROCESSABORT: + /* nothing to do, add tracing in future patch */ + break; + } +} + +/* Some kind of closing has been received: peer_conn_closed, peer_conn_abort, + * or peer_done_writing. + * Called under tasklet context. + */ +void smc_close_passive_received(struct smc_sock *smc) +{ + struct smc_cdc_conn_state_flags *rxflags = + &smc->conn.local_rx_ctrl.conn_state_flags; + struct sock *sk = &smc->sk; + int old_state; + + sk->sk_shutdown |= RCV_SHUTDOWN; + if (smc->clcsock && smc->clcsock->sk) + smc->clcsock->sk->sk_shutdown |= RCV_SHUTDOWN; + sock_set_flag(&smc->sk, SOCK_DONE); + + old_state = sk->sk_state; + + if (rxflags->peer_conn_abort) { + smc_close_passive_abort_received(smc); + goto wakeup; + } + + switch (sk->sk_state) { + case SMC_INIT: + if (atomic_read(&smc->conn.bytes_to_rcv) || + (rxflags->peer_done_writing && + !rxflags->peer_conn_closed)) + sk->sk_state = SMC_APPCLOSEWAIT1; + else + sk->sk_state = SMC_CLOSED; + break; + case SMC_ACTIVE: + sk->sk_state = SMC_APPCLOSEWAIT1; + break; + case SMC_PEERCLOSEWAIT1: + if (rxflags->peer_done_writing) + sk->sk_state = SMC_PEERCLOSEWAIT2; + /* fall through to check for closing */ + case SMC_PEERCLOSEWAIT2: + case SMC_PEERFINCLOSEWAIT: + if (!smc_cdc_rxed_any_close(&smc->conn)) + break; + if (sock_flag(sk, SOCK_DEAD) && + (sk->sk_shutdown == SHUTDOWN_MASK)) { + /* 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; + } + break; + case SMC_APPCLOSEWAIT1: + case SMC_APPCLOSEWAIT2: + case SMC_APPFINCLOSEWAIT: + case SMC_PEERABORTWAIT: + case SMC_PROCESSABORT: + case SMC_CLOSED: + /* nothing to do, add tracing in future patch */ + break; + } + +wakeup: + if (old_state != sk->sk_state) + sk->sk_state_change(sk); + sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */ + sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */ + + if ((sk->sk_state == SMC_CLOSED) && + (sock_flag(sk, SOCK_DEAD) || (old_state == SMC_INIT))) { + smc_conn_free(&smc->conn); + schedule_delayed_work(&smc->sock_put_work, + SMC_CLOSE_SOCK_PUT_DELAY); + } +} + +void smc_close_sock_put_work(struct work_struct *work) +{ + struct smc_sock *smc = container_of(to_delayed_work(work), + struct smc_sock, + sock_put_work); + + sock_put(&smc->sk); +} + +int smc_close_shutdown_write(struct smc_sock *smc) +{ + struct smc_connection *conn = &smc->conn; + long timeout = SMC_MAX_STREAM_WAIT_TIMEOUT; + struct sock *sk = &smc->sk; + int old_state; + int rc = 0; + + if (sock_flag(sk, SOCK_LINGER)) + timeout = sk->sk_lingertime; + +again: + old_state = sk->sk_state; + switch (old_state) { + case SMC_ACTIVE: + smc_close_stream_wait(smc, timeout); + release_sock(sk); + cancel_work_sync(&conn->tx_work); + lock_sock(sk); + /* send close wr request */ + rc = smc_close_wr(conn); + if (sk->sk_state == SMC_ACTIVE) + sk->sk_state = SMC_PEERCLOSEWAIT1; + else + goto again; + break; + case SMC_APPCLOSEWAIT1: + /* passive close */ + if (!smc_cdc_rxed_any_close(conn)) + smc_close_stream_wait(smc, timeout); + release_sock(sk); + cancel_work_sync(&conn->tx_work); + lock_sock(sk); + /* confirm close from peer */ + rc = smc_close_wr(conn); + 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(&smc->sk); + return rc; +} |