[mirror_ubuntu-jammy-kernel.git] / net / smc / smc_close.c

// 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"

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
 * 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);
		break;
	case SMC_APPCLOSEWAIT1:
	case SMC_APPCLOSEWAIT2:
		txflags->peer_conn_abort = 1;
		sock_release(smc->clcsock);
		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) {
			sk->sk_state = SMC_PEERABORTWAIT;
			txflags->peer_conn_abort = 1;
			sock_release(smc->clcsock);
		} else {
			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);
		}
		sk->sk_state = SMC_CLOSED;
		break;
	case SMC_PEERFINCLOSEWAIT:
	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;
		if (smc->smc_listen_work.func)
			cancel_work_sync(&smc->smc_listen_work);
		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);
		cancel_work_sync(&smc->smc_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;
		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_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 &&
		    !smc_close_sent_any_close(&smc->conn)) {
			/* 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.
 */
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) {
		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;
		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(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;
		}
		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:
	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);
			schedule_delayed_work(&smc->sock_put_work,
					      SMC_CLOSE_SOCK_PUT_DELAY);
		}
	}
	release_sock(sk);
}

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);

	smc->sk.sk_prot->unhash(&smc->sk);
	sock_put(&smc->sk);
}

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);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
b38d7324 UB	2	/*
	3	* Shared Memory Communications over RDMA (SMC-R) and RoCE
	4	*
	5	* Socket Closing - normal and abnormal
	6	*
	7	* Copyright IBM Corp. 2016
	8	*
	9	* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
	10	*/
	11
	12	#include <linux/workqueue.h>
c3edc401 IM	13	#include <linux/sched/signal.h>
c3edc401 IM	14
b38d7324 UB	15	#include <net/sock.h>
	16
	17	#include "smc.h"
	18	#include "smc_tx.h"
	19	#include "smc_cdc.h"
	20	#include "smc_close.h"
	21
b38d7324 UB	22	static void smc_close_cleanup_listen(struct sock *parent)
	23	{
	24	struct sock *sk;
	25
	26	/* Close non-accepted connections */
	27	while ((sk = smc_accept_dequeue(parent, NULL)))
	28	smc_close_non_accepted(sk);
	29	}
	30
b38d7324 UB	31	/* wait for sndbuf data being transmitted */
	32	static void smc_close_stream_wait(struct smc_sock *smc, long timeout)
	33	{
	34	DEFINE_WAIT_FUNC(wait, woken_wake_function);
	35	struct sock *sk = &smc->sk;
	36
	37	if (!timeout)
	38	return;
	39
	40	if (!smc_tx_prepared_sends(&smc->conn))
	41	return;
	42
	43	smc->wait_close_tx_prepared = 1;
	44	add_wait_queue(sk_sleep(sk), &wait);
	45	while (!signal_pending(current) && timeout) {
	46	int rc;
	47
	48	rc = sk_wait_event(sk, &timeout,
	49	!smc_tx_prepared_sends(&smc->conn) \|\|
	50	(sk->sk_err == ECONNABORTED) \|\|
	51	(sk->sk_err == ECONNRESET),
	52	&wait);
	53	if (rc)
	54	break;
	55	}
	56	remove_wait_queue(sk_sleep(sk), &wait);
	57	smc->wait_close_tx_prepared = 0;
	58	}
	59
	60	void smc_close_wake_tx_prepared(struct smc_sock *smc)
	61	{
	62	if (smc->wait_close_tx_prepared)
	63	/* wake up socket closing */
	64	smc->sk.sk_state_change(&smc->sk);
	65	}
	66
	67	static int smc_close_wr(struct smc_connection *conn)
	68	{
	69	conn->local_tx_ctrl.conn_state_flags.peer_done_writing = 1;
	70
	71	return smc_cdc_get_slot_and_msg_send(conn);
	72	}
	73
	74	static int smc_close_final(struct smc_connection *conn)
	75	{
	76	if (atomic_read(&conn->bytes_to_rcv))
	77	conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
	78	else
	79	conn->local_tx_ctrl.conn_state_flags.peer_conn_closed = 1;
	80
	81	return smc_cdc_get_slot_and_msg_send(conn);
	82	}
	83
	84	static int smc_close_abort(struct smc_connection *conn)
	85	{
	86	conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
	87
	88	return smc_cdc_get_slot_and_msg_send(conn);
	89	}
	90
	91	/* terminate smc socket abnormally - active abort
	92	* RDMA communication no longer possible
	93	*/
a8ae890b	94	static void smc_close_active_abort(struct smc_sock *smc)
b38d7324	95	{
3163c507 UB	96	struct sock *sk = &smc->sk;
3163c507 UB	97
b38d7324 UB	98	struct smc_cdc_conn_state_flags *txflags =
	99	&smc->conn.local_tx_ctrl.conn_state_flags;
	100
3163c507	101	sk->sk_err = ECONNABORTED;
b38d7324 UB	102	if (smc->clcsock && smc->clcsock->sk) {
	103	smc->clcsock->sk->sk_err = ECONNABORTED;
	104	smc->clcsock->sk->sk_state_change(smc->clcsock->sk);
	105	}
3163c507	106	switch (sk->sk_state) {
b38d7324	107	case SMC_INIT:
46c28dbd	108	case SMC_ACTIVE:
3163c507	109	sk->sk_state = SMC_PEERABORTWAIT;
611b63a1 UB	110	release_sock(sk);
	111	cancel_delayed_work_sync(&smc->conn.tx_work);
	112	lock_sock(sk);
b38d7324 UB	113	break;
	114	case SMC_APPCLOSEWAIT1:
	115	case SMC_APPCLOSEWAIT2:
	116	txflags->peer_conn_abort = 1;
	117	sock_release(smc->clcsock);
	118	if (!smc_cdc_rxed_any_close(&smc->conn))
3163c507	119	sk->sk_state = SMC_PEERABORTWAIT;
b38d7324	120	else
3163c507	121	sk->sk_state = SMC_CLOSED;
611b63a1 UB	122	release_sock(sk);
	123	cancel_delayed_work_sync(&smc->conn.tx_work);
	124	lock_sock(sk);
b38d7324 UB	125	break;
	126	case SMC_PEERCLOSEWAIT1:
	127	case SMC_PEERCLOSEWAIT2:
	128	if (!txflags->peer_conn_closed) {
3163c507	129	sk->sk_state = SMC_PEERABORTWAIT;
b38d7324 UB	130	txflags->peer_conn_abort = 1;
	131	sock_release(smc->clcsock);
	132	} else {
3163c507	133	sk->sk_state = SMC_CLOSED;
b38d7324 UB	134	}
	135	break;
	136	case SMC_PROCESSABORT:
	137	case SMC_APPFINCLOSEWAIT:
	138	if (!txflags->peer_conn_closed) {
	139	txflags->peer_conn_abort = 1;
	140	sock_release(smc->clcsock);
	141	}
3163c507	142	sk->sk_state = SMC_CLOSED;
b38d7324 UB	143	break;
	144	case SMC_PEERFINCLOSEWAIT:
	145	case SMC_PEERABORTWAIT:
	146	case SMC_CLOSED:
	147	break;
	148	}
	149
3163c507 UB	150	sock_set_flag(sk, SOCK_DEAD);
3163c507 UB	151	sk->sk_state_change(sk);
b38d7324 UB	152	}
b38d7324 UB	153
a98bf8c0 UB	154	static inline bool smc_close_sent_any_close(struct smc_connection *conn)
	155	{
	156	return conn->local_tx_ctrl.conn_state_flags.peer_conn_abort \|\|
	157	conn->local_tx_ctrl.conn_state_flags.peer_conn_closed;
	158	}
	159
b38d7324 UB	160	int smc_close_active(struct smc_sock *smc)
	161	{
	162	struct smc_cdc_conn_state_flags *txflags =
	163	&smc->conn.local_tx_ctrl.conn_state_flags;
b38d7324 UB	164	struct smc_connection *conn = &smc->conn;
	165	struct sock *sk = &smc->sk;
	166	int old_state;
8c96feee	167	long timeout;
b38d7324 UB	168	int rc = 0;
b38d7324 UB	169
8c96feee UB	170	timeout = current->flags & PF_EXITING ?
	171	0 : sock_flag(sk, SOCK_LINGER) ?
	172	sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
b38d7324	173
b38d7324	174	old_state = sk->sk_state;
bbb96bf2 UB	175	again:
bbb96bf2 UB	176	switch (sk->sk_state) {
b38d7324 UB	177	case SMC_INIT:
	178	sk->sk_state = SMC_CLOSED;
	179	if (smc->smc_listen_work.func)
46c28dbd	180	cancel_work_sync(&smc->smc_listen_work);
b38d7324 UB	181	break;
	182	case SMC_LISTEN:
	183	sk->sk_state = SMC_CLOSED;
	184	sk->sk_state_change(sk); /* wake up accept */
	185	if (smc->clcsock && smc->clcsock->sk) {
	186	rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
	187	/* wake up kernel_accept of smc_tcp_listen_worker */
	188	smc->clcsock->sk->sk_data_ready(smc->clcsock->sk);
	189	}
	190	release_sock(sk);
	191	smc_close_cleanup_listen(sk);
46c28dbd	192	cancel_work_sync(&smc->smc_listen_work);
b38d7324 UB	193	lock_sock(sk);
	194	break;
	195	case SMC_ACTIVE:
	196	smc_close_stream_wait(smc, timeout);
	197	release_sock(sk);
18e537cd	198	cancel_delayed_work_sync(&conn->tx_work);
b38d7324 UB	199	lock_sock(sk);
	200	if (sk->sk_state == SMC_ACTIVE) {
	201	/* send close request */
	202	rc = smc_close_final(conn);
bbb96bf2 UB	203	if (rc)
bbb96bf2 UB	204	break;
b38d7324 UB	205	sk->sk_state = SMC_PEERCLOSEWAIT1;
	206	} else {
	207	/* peer event has changed the state */
	208	goto again;
	209	}
	210	break;
	211	case SMC_APPFINCLOSEWAIT:
	212	/* socket already shutdown wr or both (active close) */
	213	if (txflags->peer_done_writing &&
a98bf8c0	214	!smc_close_sent_any_close(conn)) {
b38d7324 UB	215	/* just shutdown wr done, send close request */
b38d7324 UB	216	rc = smc_close_final(conn);
bbb96bf2 UB	217	if (rc)
bbb96bf2 UB	218	break;
b38d7324 UB	219	}
b38d7324 UB	220	sk->sk_state = SMC_CLOSED;
b38d7324 UB	221	break;
	222	case SMC_APPCLOSEWAIT1:
	223	case SMC_APPCLOSEWAIT2:
	224	if (!smc_cdc_rxed_any_close(conn))
	225	smc_close_stream_wait(smc, timeout);
	226	release_sock(sk);
18e537cd	227	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	228	lock_sock(sk);
bbb96bf2 UB	229	if (sk->sk_state != SMC_APPCLOSEWAIT1 &&
	230	sk->sk_state != SMC_APPCLOSEWAIT2)
	231	goto again;
	232	/* confirm close from peer */
	233	rc = smc_close_final(conn);
	234	if (rc)
	235	break;
b38d7324 UB	236	if (smc_cdc_rxed_any_close(conn))
	237	/* peer has closed the socket already */
	238	sk->sk_state = SMC_CLOSED;
	239	else
	240	/* peer has just issued a shutdown write */
	241	sk->sk_state = SMC_PEERFINCLOSEWAIT;
b38d7324 UB	242	break;
	243	case SMC_PEERCLOSEWAIT1:
	244	case SMC_PEERCLOSEWAIT2:
a98bf8c0 UB	245	if (txflags->peer_done_writing &&
	246	!smc_close_sent_any_close(conn)) {
	247	/* just shutdown wr done, send close request */
	248	rc = smc_close_final(conn);
bbb96bf2 UB	249	if (rc)
bbb96bf2 UB	250	break;
a98bf8c0 UB	251	}
	252	/* peer sending PeerConnectionClosed will cause transition */
	253	break;
b38d7324 UB	254	case SMC_PEERFINCLOSEWAIT:
	255	/* peer sending PeerConnectionClosed will cause transition */
	256	break;
	257	case SMC_PROCESSABORT:
b38d7324 UB	258	smc_close_abort(conn);
b38d7324 UB	259	sk->sk_state = SMC_CLOSED;
b38d7324 UB	260	break;
	261	case SMC_PEERABORTWAIT:
	262	case SMC_CLOSED:
	263	/* nothing to do, add tracing in future patch */
	264	break;
	265	}
	266
	267	if (old_state != sk->sk_state)
3163c507	268	sk->sk_state_change(sk);
b38d7324 UB	269	return rc;
	270	}
	271
	272	static void smc_close_passive_abort_received(struct smc_sock *smc)
	273	{
	274	struct smc_cdc_conn_state_flags *txflags =
	275	&smc->conn.local_tx_ctrl.conn_state_flags;
	276	struct sock *sk = &smc->sk;
	277
	278	switch (sk->sk_state) {
	279	case SMC_ACTIVE:
	280	case SMC_APPFINCLOSEWAIT:
	281	case SMC_APPCLOSEWAIT1:
	282	case SMC_APPCLOSEWAIT2:
	283	smc_close_abort(&smc->conn);
	284	sk->sk_state = SMC_PROCESSABORT;
	285	break;
	286	case SMC_PEERCLOSEWAIT1:
	287	case SMC_PEERCLOSEWAIT2:
	288	if (txflags->peer_done_writing &&
a98bf8c0	289	!smc_close_sent_any_close(&smc->conn)) {
b38d7324 UB	290	/* just shutdown, but not yet closed locally */
	291	smc_close_abort(&smc->conn);
	292	sk->sk_state = SMC_PROCESSABORT;
	293	} else {
	294	sk->sk_state = SMC_CLOSED;
	295	}
	296	break;
	297	case SMC_PEERFINCLOSEWAIT:
	298	case SMC_PEERABORTWAIT:
	299	sk->sk_state = SMC_CLOSED;
	300	break;
	301	case SMC_INIT:
	302	case SMC_PROCESSABORT:
	303	/* nothing to do, add tracing in future patch */
	304	break;
	305	}
	306	}
	307
	308	/* Some kind of closing has been received: peer_conn_closed, peer_conn_abort,
	309	* or peer_done_writing.
b38d7324	310	*/
46c28dbd	311	static void smc_close_passive_work(struct work_struct *work)
b38d7324	312	{
46c28dbd UB	313	struct smc_connection *conn = container_of(work,
	314	struct smc_connection,
	315	close_work);
	316	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
	317	struct smc_cdc_conn_state_flags *rxflags;
b38d7324 UB	318	struct sock *sk = &smc->sk;
	319	int old_state;
	320
3163c507	321	lock_sock(sk);
b38d7324 UB	322	old_state = sk->sk_state;
b38d7324 UB	323
46c28dbd UB	324	if (!conn->alert_token_local) {
	325	/* abnormal termination */
	326	smc_close_active_abort(smc);
	327	goto wakeup;
	328	}
	329
3163c507	330	rxflags = &conn->local_rx_ctrl.conn_state_flags;
b38d7324 UB	331	if (rxflags->peer_conn_abort) {
b38d7324 UB	332	smc_close_passive_abort_received(smc);
611b63a1 UB	333	release_sock(&smc->sk);
	334	cancel_delayed_work_sync(&conn->tx_work);
	335	lock_sock(&smc->sk);
b38d7324 UB	336	goto wakeup;
	337	}
	338
	339	switch (sk->sk_state) {
	340	case SMC_INIT:
3163c507	341	if (atomic_read(&conn->bytes_to_rcv) \|\|
b38d7324	342	(rxflags->peer_done_writing &&
a98bf8c0	343	!smc_cdc_rxed_any_close(conn)))
b38d7324 UB	344	sk->sk_state = SMC_APPCLOSEWAIT1;
	345	else
	346	sk->sk_state = SMC_CLOSED;
	347	break;
	348	case SMC_ACTIVE:
	349	sk->sk_state = SMC_APPCLOSEWAIT1;
	350	break;
	351	case SMC_PEERCLOSEWAIT1:
	352	if (rxflags->peer_done_writing)
	353	sk->sk_state = SMC_PEERCLOSEWAIT2;
7f6b437e GS	354	/* fall through */
7f6b437e GS	355	/* to check for closing */
b38d7324 UB	356	case SMC_PEERCLOSEWAIT2:
b38d7324 UB	357	case SMC_PEERFINCLOSEWAIT:
3163c507	358	if (!smc_cdc_rxed_any_close(conn))
b38d7324 UB	359	break;
b38d7324 UB	360	if (sock_flag(sk, SOCK_DEAD) &&
a98bf8c0	361	smc_close_sent_any_close(conn)) {
b38d7324 UB	362	/* smc_release has already been called locally */
	363	sk->sk_state = SMC_CLOSED;
	364	} else {
	365	/* just shutdown, but not yet closed locally */
	366	sk->sk_state = SMC_APPFINCLOSEWAIT;
	367	}
	368	break;
	369	case SMC_APPCLOSEWAIT1:
	370	case SMC_APPCLOSEWAIT2:
	371	case SMC_APPFINCLOSEWAIT:
	372	case SMC_PEERABORTWAIT:
	373	case SMC_PROCESSABORT:
	374	case SMC_CLOSED:
	375	/* nothing to do, add tracing in future patch */
	376	break;
	377	}
	378
	379	wakeup:
b38d7324 UB	380	sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */
	381	sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */
	382
a98bf8c0 UB	383	if (old_state != sk->sk_state) {
	384	sk->sk_state_change(sk);
	385	if ((sk->sk_state == SMC_CLOSED) &&
	386	(sock_flag(sk, SOCK_DEAD) \|\| !sk->sk_socket)) {
3163c507	387	smc_conn_free(conn);
a98bf8c0 UB	388	schedule_delayed_work(&smc->sock_put_work,
	389	SMC_CLOSE_SOCK_PUT_DELAY);
	390	}
b38d7324	391	}
3163c507	392	release_sock(sk);
b38d7324 UB	393	}
	394
	395	void smc_close_sock_put_work(struct work_struct *work)
	396	{
	397	struct smc_sock *smc = container_of(to_delayed_work(work),
	398	struct smc_sock,
	399	sock_put_work);
	400
f16a7dd5	401	smc->sk.sk_prot->unhash(&smc->sk);
b38d7324 UB	402	sock_put(&smc->sk);
	403	}
	404
	405	int smc_close_shutdown_write(struct smc_sock *smc)
	406	{
	407	struct smc_connection *conn = &smc->conn;
b38d7324 UB	408	struct sock *sk = &smc->sk;
b38d7324 UB	409	int old_state;
8c96feee	410	long timeout;
b38d7324 UB	411	int rc = 0;
b38d7324 UB	412
8c96feee UB	413	timeout = current->flags & PF_EXITING ?
	414	0 : sock_flag(sk, SOCK_LINGER) ?
	415	sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
b38d7324	416
b38d7324	417	old_state = sk->sk_state;
bbb96bf2 UB	418	again:
bbb96bf2 UB	419	switch (sk->sk_state) {
b38d7324 UB	420	case SMC_ACTIVE:
	421	smc_close_stream_wait(smc, timeout);
	422	release_sock(sk);
18e537cd	423	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	424	lock_sock(sk);
bbb96bf2 UB	425	if (sk->sk_state != SMC_ACTIVE)
bbb96bf2 UB	426	goto again;
b38d7324 UB	427	/* send close wr request */
b38d7324 UB	428	rc = smc_close_wr(conn);
bbb96bf2 UB	429	if (rc)
	430	break;
	431	sk->sk_state = SMC_PEERCLOSEWAIT1;
b38d7324 UB	432	break;
	433	case SMC_APPCLOSEWAIT1:
	434	/* passive close */
	435	if (!smc_cdc_rxed_any_close(conn))
	436	smc_close_stream_wait(smc, timeout);
	437	release_sock(sk);
18e537cd	438	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	439	lock_sock(sk);
bbb96bf2 UB	440	if (sk->sk_state != SMC_APPCLOSEWAIT1)
bbb96bf2 UB	441	goto again;
b38d7324 UB	442	/* confirm close from peer */
b38d7324 UB	443	rc = smc_close_wr(conn);
bbb96bf2 UB	444	if (rc)
bbb96bf2 UB	445	break;
b38d7324 UB	446	sk->sk_state = SMC_APPCLOSEWAIT2;
	447	break;
	448	case SMC_APPCLOSEWAIT2:
	449	case SMC_PEERFINCLOSEWAIT:
	450	case SMC_PEERCLOSEWAIT1:
	451	case SMC_PEERCLOSEWAIT2:
	452	case SMC_APPFINCLOSEWAIT:
	453	case SMC_PROCESSABORT:
	454	case SMC_PEERABORTWAIT:
	455	/* nothing to do, add tracing in future patch */
	456	break;
	457	}
	458
	459	if (old_state != sk->sk_state)
3163c507	460	sk->sk_state_change(sk);
b38d7324 UB	461	return rc;
b38d7324 UB	462	}
46c28dbd UB	463
	464	/* Initialize close properties on connection establishment. */
	465	void smc_close_init(struct smc_sock *smc)
	466	{
	467	INIT_WORK(&smc->conn.close_work, smc_close_passive_work);
	468	}