v4.19.13 snapshot.
diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c
new file mode 100644
index 0000000..ea2b87f
--- /dev/null
+++ b/net/smc/smc_close.c
@@ -0,0 +1,478 @@
+// 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);
+}
+
+/* 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;
+
+ if (sk->sk_state != SMC_INIT && smc->clcsock && smc->clcsock->sk) {
+ 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_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_INIT:
+ 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_cleanup_listen(sk);
+ release_sock(sk);
+ flush_work(&smc->tcp_listen_work);
+ lock_sock(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);
+}