[linux-2.6-block.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 <net/tcp.h>

#include "smc.h"
#include "smc_tx.h"
#include "smc_cdc.h"
#include "smc_close.h"

/* release the clcsock that is assigned to the smc_sock */
void smc_clcsock_release(struct smc_sock *smc)
{
	struct socket *tcp;

	if (smc->listen_smc && current_work() != &smc->smc_listen_work)
		cancel_work_sync(&smc->smc_listen_work);
	mutex_lock(&smc->clcsock_release_lock);
	if (smc->clcsock) {
		tcp = smc->clcsock;
		smc->clcsock = NULL;
		sock_release(tcp);
	}
	mutex_unlock(&smc->clcsock_release_lock);
}

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 ||
				   smc->conn.killed,
				   &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;
	if (conn->killed)
		return -EPIPE;

	return smc_cdc_get_slot_and_msg_send(conn);
}

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);
}

static void smc_close_cancel_work(struct smc_sock *smc)
{
	struct sock *sk = &smc->sk;

	release_sock(sk);
	cancel_work_sync(&smc->conn.close_work);
	cancel_delayed_work_sync(&smc->conn.tx_work);
	lock_sock(sk);
	sk->sk_state = SMC_CLOSED;
}

/* terminate smc socket abnormally - active abort
 * link group is terminated, i.e. RDMA communication no longer possible
 */
void smc_close_active_abort(struct smc_sock *smc)
{
	struct sock *sk = &smc->sk;
	bool release_clcsock = false;

	if (sk->sk_state != SMC_INIT && smc->clcsock && smc->clcsock->sk) {
		sk->sk_err = ECONNABORTED;
		if (smc->clcsock && smc->clcsock->sk)
			tcp_abort(smc->clcsock->sk, ECONNABORTED);
	}
	switch (sk->sk_state) {
	case SMC_ACTIVE:
		sk->sk_state = SMC_PEERABORTWAIT;
		smc_close_cancel_work(smc);
		sk->sk_state = SMC_CLOSED;
		sock_put(sk); /* passive closing */
		break;
	case SMC_APPCLOSEWAIT1:
	case SMC_APPCLOSEWAIT2:
		smc_close_cancel_work(smc);
		sk->sk_state = SMC_CLOSED;
		sock_put(sk); /* postponed passive closing */
		break;
	case SMC_PEERCLOSEWAIT1:
	case SMC_PEERCLOSEWAIT2:
	case SMC_PEERFINCLOSEWAIT:
		sk->sk_state = SMC_PEERABORTWAIT;
		smc_close_cancel_work(smc);
		sk->sk_state = SMC_CLOSED;
		smc_conn_free(&smc->conn);
		release_clcsock = true;
		sock_put(sk); /* passive closing */
		break;
	case SMC_PROCESSABORT:
	case SMC_APPFINCLOSEWAIT:
		sk->sk_state = SMC_PEERABORTWAIT;
		smc_close_cancel_work(smc);
		sk->sk_state = SMC_CLOSED;
		smc_conn_free(&smc->conn);
		release_clcsock = true;
		break;
	case SMC_INIT:
	case SMC_PEERABORTWAIT:
	case SMC_CLOSED:
		break;
	}

	sock_set_flag(sk, SOCK_DEAD);
	sk->sk_state_change(sk);

	if (release_clcsock) {
		release_sock(sk);
		smc_clcsock_release(smc);
		lock_sock(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);
			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);
		}
		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 (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);
		}
		/* peer sending PeerConnectionClosed will cause transition */
		break;
	case SMC_PEERFINCLOSEWAIT:
		/* peer sending PeerConnectionClosed will cause transition */
		break;
	case SMC_PROCESSABORT:
		rc = smc_close_abort(conn);
		sk->sk_state = SMC_CLOSED;
		break;
	case SMC_PEERABORTWAIT:
		sk->sk_state = SMC_CLOSED;
		break;
	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;
	bool release_clcsock = false;
	struct sock *sk = &smc->sk;
	int old_state;

	lock_sock(sk);
	old_state = sk->sk_state;

	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:
		sk->sk_state = SMC_APPCLOSEWAIT1;
		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);
			if (smc->clcsock)
				release_clcsock = true;
		}
	}
	release_sock(sk);
	if (release_clcsock)
		smc_clcsock_release(smc);
	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);
		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);
		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	15	#include <net/sock.h>
83179760	16	#include <net/tcp.h>
b38d7324 UB	17
	18	#include "smc.h"
	19	#include "smc_tx.h"
	20	#include "smc_cdc.h"
	21	#include "smc_close.h"
	22
fd57770d KG	23	/* release the clcsock that is assigned to the smc_sock */
	24	void smc_clcsock_release(struct smc_sock *smc)
	25	{
	26	struct socket *tcp;
	27
	28	if (smc->listen_smc && current_work() != &smc->smc_listen_work)
	29	cancel_work_sync(&smc->smc_listen_work);
	30	mutex_lock(&smc->clcsock_release_lock);
	31	if (smc->clcsock) {
	32	tcp = smc->clcsock;
	33	smc->clcsock = NULL;
	34	sock_release(tcp);
	35	}
	36	mutex_unlock(&smc->clcsock_release_lock);
	37	}
	38
b38d7324 UB	39	static void smc_close_cleanup_listen(struct sock *parent)
	40	{
	41	struct sock *sk;
	42
	43	/* Close non-accepted connections */
	44	while ((sk = smc_accept_dequeue(parent, NULL)))
	45	smc_close_non_accepted(sk);
	46	}
	47
b38d7324 UB	48	/* wait for sndbuf data being transmitted */
	49	static void smc_close_stream_wait(struct smc_sock *smc, long timeout)
	50	{
	51	DEFINE_WAIT_FUNC(wait, woken_wake_function);
	52	struct sock *sk = &smc->sk;
	53
	54	if (!timeout)
	55	return;
	56
	57	if (!smc_tx_prepared_sends(&smc->conn))
	58	return;
	59
	60	smc->wait_close_tx_prepared = 1;
	61	add_wait_queue(sk_sleep(sk), &wait);
	62	while (!signal_pending(current) && timeout) {
	63	int rc;
	64
	65	rc = sk_wait_event(sk, &timeout,
	66	!smc_tx_prepared_sends(&smc->conn) \|\|
d18963cf	67	sk->sk_err == ECONNABORTED \|\|
b2900980 UB	68	sk->sk_err == ECONNRESET \|\|
b2900980 UB	69	smc->conn.killed,
b38d7324 UB	70	&wait);
	71	if (rc)
	72	break;
	73	}
	74	remove_wait_queue(sk_sleep(sk), &wait);
	75	smc->wait_close_tx_prepared = 0;
	76	}
	77
	78	void smc_close_wake_tx_prepared(struct smc_sock *smc)
	79	{
	80	if (smc->wait_close_tx_prepared)
	81	/* wake up socket closing */
	82	smc->sk.sk_state_change(&smc->sk);
	83	}
	84
	85	static int smc_close_wr(struct smc_connection *conn)
	86	{
	87	conn->local_tx_ctrl.conn_state_flags.peer_done_writing = 1;
	88
	89	return smc_cdc_get_slot_and_msg_send(conn);
	90	}
	91
	92	static int smc_close_final(struct smc_connection *conn)
	93	{
	94	if (atomic_read(&conn->bytes_to_rcv))
	95	conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
	96	else
	97	conn->local_tx_ctrl.conn_state_flags.peer_conn_closed = 1;
b2900980 UB	98	if (conn->killed)
b2900980 UB	99	return -EPIPE;
b38d7324 UB	100
	101	return smc_cdc_get_slot_and_msg_send(conn);
	102	}
	103
83179760	104	int smc_close_abort(struct smc_connection *conn)
b38d7324 UB	105	{
	106	conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
	107
	108	return smc_cdc_get_slot_and_msg_send(conn);
	109	}
	110
42bfba9e UB	111	static void smc_close_cancel_work(struct smc_sock *smc)
	112	{
	113	struct sock *sk = &smc->sk;
	114
	115	release_sock(sk);
	116	cancel_work_sync(&smc->conn.close_work);
	117	cancel_delayed_work_sync(&smc->conn.tx_work);
	118	lock_sock(sk);
	119	sk->sk_state = SMC_CLOSED;
	120	}
	121
b38d7324	122	/* terminate smc socket abnormally - active abort
732720fa	123	* link group is terminated, i.e. RDMA communication no longer possible
b38d7324	124	*/
81cf4f47	125	void smc_close_active_abort(struct smc_sock *smc)
b38d7324	126	{
3163c507	127	struct sock *sk = &smc->sk;
81cf4f47	128	bool release_clcsock = false;
3163c507	129
dd65d87a UB	130	if (sk->sk_state != SMC_INIT && smc->clcsock && smc->clcsock->sk) {
dd65d87a UB	131	sk->sk_err = ECONNABORTED;
83179760 UB	132	if (smc->clcsock && smc->clcsock->sk)
83179760 UB	133	tcp_abort(smc->clcsock->sk, ECONNABORTED);
b38d7324	134	}
3163c507	135	switch (sk->sk_state) {
46c28dbd	136	case SMC_ACTIVE:
3163c507	137	sk->sk_state = SMC_PEERABORTWAIT;
42bfba9e	138	smc_close_cancel_work(smc);
d18963cf	139	sk->sk_state = SMC_CLOSED;
51f1de79	140	sock_put(sk); /* passive closing */
b38d7324 UB	141	break;
	142	case SMC_APPCLOSEWAIT1:
	143	case SMC_APPCLOSEWAIT2:
42bfba9e	144	smc_close_cancel_work(smc);
d18963cf	145	sk->sk_state = SMC_CLOSED;
81cf4f47	146	sock_put(sk); /* postponed passive closing */
b38d7324 UB	147	break;
	148	case SMC_PEERCLOSEWAIT1:
	149	case SMC_PEERCLOSEWAIT2:
d18963cf	150	case SMC_PEERFINCLOSEWAIT:
42bfba9e UB	151	sk->sk_state = SMC_PEERABORTWAIT;
42bfba9e UB	152	smc_close_cancel_work(smc);
d18963cf	153	sk->sk_state = SMC_CLOSED;
81cf4f47 UB	154	smc_conn_free(&smc->conn);
81cf4f47 UB	155	release_clcsock = true;
51f1de79	156	sock_put(sk); /* passive closing */
b38d7324 UB	157	break;
	158	case SMC_PROCESSABORT:
	159	case SMC_APPFINCLOSEWAIT:
42bfba9e UB	160	sk->sk_state = SMC_PEERABORTWAIT;
42bfba9e UB	161	smc_close_cancel_work(smc);
3163c507	162	sk->sk_state = SMC_CLOSED;
42bfba9e UB	163	smc_conn_free(&smc->conn);
42bfba9e UB	164	release_clcsock = true;
b38d7324	165	break;
dd65d87a	166	case SMC_INIT:
b38d7324 UB	167	case SMC_PEERABORTWAIT:
	168	case SMC_CLOSED:
	169	break;
	170	}
	171
3163c507 UB	172	sock_set_flag(sk, SOCK_DEAD);
3163c507 UB	173	sk->sk_state_change(sk);
81cf4f47 UB	174
	175	if (release_clcsock) {
	176	release_sock(sk);
	177	smc_clcsock_release(smc);
	178	lock_sock(sk);
	179	}
b38d7324 UB	180	}
b38d7324 UB	181
a98bf8c0 UB	182	static inline bool smc_close_sent_any_close(struct smc_connection *conn)
	183	{
	184	return conn->local_tx_ctrl.conn_state_flags.peer_conn_abort \|\|
	185	conn->local_tx_ctrl.conn_state_flags.peer_conn_closed;
	186	}
	187
b38d7324 UB	188	int smc_close_active(struct smc_sock *smc)
	189	{
	190	struct smc_cdc_conn_state_flags *txflags =
	191	&smc->conn.local_tx_ctrl.conn_state_flags;
b38d7324 UB	192	struct smc_connection *conn = &smc->conn;
	193	struct sock *sk = &smc->sk;
	194	int old_state;
8c96feee	195	long timeout;
b38d7324 UB	196	int rc = 0;
b38d7324 UB	197
8c96feee UB	198	timeout = current->flags & PF_EXITING ?
	199	0 : sock_flag(sk, SOCK_LINGER) ?
	200	sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
b38d7324	201
b38d7324	202	old_state = sk->sk_state;
bbb96bf2 UB	203	again:
bbb96bf2 UB	204	switch (sk->sk_state) {
b38d7324 UB	205	case SMC_INIT:
b38d7324 UB	206	sk->sk_state = SMC_CLOSED;
b38d7324 UB	207	break;
	208	case SMC_LISTEN:
	209	sk->sk_state = SMC_CLOSED;
	210	sk->sk_state_change(sk); /* wake up accept */
	211	if (smc->clcsock && smc->clcsock->sk) {
	212	rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
	213	/* wake up kernel_accept of smc_tcp_listen_worker */
	214	smc->clcsock->sk->sk_data_ready(smc->clcsock->sk);
	215	}
b38d7324	216	smc_close_cleanup_listen(sk);
3d502067 UB	217	release_sock(sk);
	218	flush_work(&smc->tcp_listen_work);
	219	lock_sock(sk);
b38d7324 UB	220	break;
	221	case SMC_ACTIVE:
	222	smc_close_stream_wait(smc, timeout);
	223	release_sock(sk);
18e537cd	224	cancel_delayed_work_sync(&conn->tx_work);
b38d7324 UB	225	lock_sock(sk);
	226	if (sk->sk_state == SMC_ACTIVE) {
	227	/* send close request */
	228	rc = smc_close_final(conn);
	229	sk->sk_state = SMC_PEERCLOSEWAIT1;
	230	} else {
	231	/* peer event has changed the state */
	232	goto again;
	233	}
	234	break;
	235	case SMC_APPFINCLOSEWAIT:
	236	/* socket already shutdown wr or both (active close) */
	237	if (txflags->peer_done_writing &&
a98bf8c0	238	!smc_close_sent_any_close(conn)) {
b38d7324 UB	239	/* just shutdown wr done, send close request */
	240	rc = smc_close_final(conn);
	241	}
	242	sk->sk_state = SMC_CLOSED;
b38d7324 UB	243	break;
	244	case SMC_APPCLOSEWAIT1:
	245	case SMC_APPCLOSEWAIT2:
	246	if (!smc_cdc_rxed_any_close(conn))
	247	smc_close_stream_wait(smc, timeout);
	248	release_sock(sk);
18e537cd	249	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	250	lock_sock(sk);
bbb96bf2 UB	251	if (sk->sk_state != SMC_APPCLOSEWAIT1 &&
	252	sk->sk_state != SMC_APPCLOSEWAIT2)
	253	goto again;
	254	/* confirm close from peer */
	255	rc = smc_close_final(conn);
51f1de79	256	if (smc_cdc_rxed_any_close(conn)) {
b38d7324 UB	257	/* peer has closed the socket already */
b38d7324 UB	258	sk->sk_state = SMC_CLOSED;
51f1de79 UB	259	sock_put(sk); /* postponed passive closing */
51f1de79 UB	260	} else {
b38d7324 UB	261	/* peer has just issued a shutdown write */
b38d7324 UB	262	sk->sk_state = SMC_PEERFINCLOSEWAIT;
51f1de79	263	}
b38d7324 UB	264	break;
	265	case SMC_PEERCLOSEWAIT1:
	266	case SMC_PEERCLOSEWAIT2:
a98bf8c0 UB	267	if (txflags->peer_done_writing &&
	268	!smc_close_sent_any_close(conn)) {
	269	/* just shutdown wr done, send close request */
	270	rc = smc_close_final(conn);
	271	}
	272	/* peer sending PeerConnectionClosed will cause transition */
	273	break;
b38d7324 UB	274	case SMC_PEERFINCLOSEWAIT:
	275	/* peer sending PeerConnectionClosed will cause transition */
	276	break;
	277	case SMC_PROCESSABORT:
d18963cf	278	rc = smc_close_abort(conn);
b38d7324	279	sk->sk_state = SMC_CLOSED;
b38d7324 UB	280	break;
b38d7324 UB	281	case SMC_PEERABORTWAIT:
d18963cf UB	282	sk->sk_state = SMC_CLOSED;
d18963cf UB	283	break;
b38d7324 UB	284	case SMC_CLOSED:
	285	/* nothing to do, add tracing in future patch */
	286	break;
	287	}
	288
	289	if (old_state != sk->sk_state)
3163c507	290	sk->sk_state_change(sk);
b38d7324 UB	291	return rc;
	292	}
	293
	294	static void smc_close_passive_abort_received(struct smc_sock *smc)
	295	{
	296	struct smc_cdc_conn_state_flags *txflags =
	297	&smc->conn.local_tx_ctrl.conn_state_flags;
	298	struct sock *sk = &smc->sk;
	299
	300	switch (sk->sk_state) {
51f1de79	301	case SMC_INIT:
b38d7324	302	case SMC_ACTIVE:
b38d7324	303	case SMC_APPCLOSEWAIT1:
51f1de79 UB	304	sk->sk_state = SMC_PROCESSABORT;
	305	sock_put(sk); /* passive closing */
	306	break;
	307	case SMC_APPFINCLOSEWAIT:
b38d7324 UB	308	sk->sk_state = SMC_PROCESSABORT;
	309	break;
	310	case SMC_PEERCLOSEWAIT1:
	311	case SMC_PEERCLOSEWAIT2:
	312	if (txflags->peer_done_writing &&
51f1de79	313	!smc_close_sent_any_close(&smc->conn))
b38d7324	314	/* just shutdown, but not yet closed locally */
b38d7324	315	sk->sk_state = SMC_PROCESSABORT;
51f1de79	316	else
b38d7324	317	sk->sk_state = SMC_CLOSED;
51f1de79	318	sock_put(sk); /* passive closing */
b38d7324	319	break;
51f1de79	320	case SMC_APPCLOSEWAIT2:
b38d7324	321	case SMC_PEERFINCLOSEWAIT:
51f1de79 UB	322	sk->sk_state = SMC_CLOSED;
	323	sock_put(sk); /* passive closing */
	324	break;
b38d7324 UB	325	case SMC_PEERABORTWAIT:
	326	sk->sk_state = SMC_CLOSED;
	327	break;
b38d7324 UB	328	case SMC_PROCESSABORT:
	329	/* nothing to do, add tracing in future patch */
	330	break;
	331	}
	332	}
	333
732720fa UB	334	/* Either some kind of closing has been received: peer_conn_closed,
	335	* peer_conn_abort, or peer_done_writing
	336	* or the link group of the connection terminates abnormally.
b38d7324	337	*/
46c28dbd	338	static void smc_close_passive_work(struct work_struct *work)
b38d7324	339	{
46c28dbd UB	340	struct smc_connection *conn = container_of(work,
	341	struct smc_connection,
	342	close_work);
	343	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
	344	struct smc_cdc_conn_state_flags *rxflags;
fd57770d	345	bool release_clcsock = false;
b38d7324 UB	346	struct sock *sk = &smc->sk;
	347	int old_state;
	348
3163c507	349	lock_sock(sk);
b38d7324 UB	350	old_state = sk->sk_state;
b38d7324 UB	351
3163c507	352	rxflags = &conn->local_rx_ctrl.conn_state_flags;
b38d7324	353	if (rxflags->peer_conn_abort) {
732720fa	354	/* peer has not received all data */
b38d7324	355	smc_close_passive_abort_received(smc);
611b63a1 UB	356	release_sock(&smc->sk);
	357	cancel_delayed_work_sync(&conn->tx_work);
	358	lock_sock(&smc->sk);
b38d7324 UB	359	goto wakeup;
	360	}
	361
	362	switch (sk->sk_state) {
	363	case SMC_INIT:
84b799a2	364	sk->sk_state = SMC_APPCLOSEWAIT1;
b38d7324 UB	365	break;
	366	case SMC_ACTIVE:
	367	sk->sk_state = SMC_APPCLOSEWAIT1;
51f1de79 UB	368	/* postpone sock_put() for passive closing to cover
	369	* received SEND_SHUTDOWN as well
	370	*/
b38d7324 UB	371	break;
	372	case SMC_PEERCLOSEWAIT1:
	373	if (rxflags->peer_done_writing)
	374	sk->sk_state = SMC_PEERCLOSEWAIT2;
7f6b437e GS	375	/* fall through */
7f6b437e GS	376	/* to check for closing */
b38d7324	377	case SMC_PEERCLOSEWAIT2:
3163c507	378	if (!smc_cdc_rxed_any_close(conn))
b38d7324 UB	379	break;
b38d7324 UB	380	if (sock_flag(sk, SOCK_DEAD) &&
a98bf8c0	381	smc_close_sent_any_close(conn)) {
b38d7324 UB	382	/* smc_release has already been called locally */
	383	sk->sk_state = SMC_CLOSED;
	384	} else {
	385	/* just shutdown, but not yet closed locally */
	386	sk->sk_state = SMC_APPFINCLOSEWAIT;
	387	}
51f1de79	388	sock_put(sk); /* passive closing */
b38d7324	389	break;
5ac92a00	390	case SMC_PEERFINCLOSEWAIT:
51f1de79	391	if (smc_cdc_rxed_any_close(conn)) {
5ac92a00	392	sk->sk_state = SMC_CLOSED;
51f1de79 UB	393	sock_put(sk); /* passive closing */
51f1de79 UB	394	}
5ac92a00	395	break;
b38d7324 UB	396	case SMC_APPCLOSEWAIT1:
b38d7324 UB	397	case SMC_APPCLOSEWAIT2:
51f1de79 UB	398	/* postpone sock_put() for passive closing to cover
	399	* received SEND_SHUTDOWN as well
	400	*/
	401	break;
b38d7324 UB	402	case SMC_APPFINCLOSEWAIT:
	403	case SMC_PEERABORTWAIT:
	404	case SMC_PROCESSABORT:
	405	case SMC_CLOSED:
	406	/* nothing to do, add tracing in future patch */
	407	break;
	408	}
	409
	410	wakeup:
b38d7324 UB	411	sk->sk_data_ready(sk); /* wakeup blocked rcvbuf consumers */
	412	sk->sk_write_space(sk); /* wakeup blocked sndbuf producers */
	413
a98bf8c0 UB	414	if (old_state != sk->sk_state) {
	415	sk->sk_state_change(sk);
	416	if ((sk->sk_state == SMC_CLOSED) &&
b03faa1f	417	(sock_flag(sk, SOCK_DEAD) \|\| !sk->sk_socket)) {
3163c507	418	smc_conn_free(conn);
fd57770d KG	419	if (smc->clcsock)
fd57770d KG	420	release_clcsock = true;
b03faa1f	421	}
b38d7324	422	}
3163c507	423	release_sock(sk);
fd57770d KG	424	if (release_clcsock)
fd57770d KG	425	smc_clcsock_release(smc);
51f1de79	426	sock_put(sk); /* sock_hold done by schedulers of close_work */
b38d7324 UB	427	}
	428
	429	int smc_close_shutdown_write(struct smc_sock *smc)
	430	{
	431	struct smc_connection *conn = &smc->conn;
b38d7324 UB	432	struct sock *sk = &smc->sk;
b38d7324 UB	433	int old_state;
8c96feee	434	long timeout;
b38d7324 UB	435	int rc = 0;
b38d7324 UB	436
8c96feee UB	437	timeout = current->flags & PF_EXITING ?
	438	0 : sock_flag(sk, SOCK_LINGER) ?
	439	sk->sk_lingertime : SMC_MAX_STREAM_WAIT_TIMEOUT;
b38d7324	440
b38d7324	441	old_state = sk->sk_state;
bbb96bf2 UB	442	again:
bbb96bf2 UB	443	switch (sk->sk_state) {
b38d7324 UB	444	case SMC_ACTIVE:
	445	smc_close_stream_wait(smc, timeout);
	446	release_sock(sk);
18e537cd	447	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	448	lock_sock(sk);
bbb96bf2 UB	449	if (sk->sk_state != SMC_ACTIVE)
bbb96bf2 UB	450	goto again;
b38d7324 UB	451	/* send close wr request */
b38d7324 UB	452	rc = smc_close_wr(conn);
bbb96bf2	453	sk->sk_state = SMC_PEERCLOSEWAIT1;
b38d7324 UB	454	break;
	455	case SMC_APPCLOSEWAIT1:
	456	/* passive close */
	457	if (!smc_cdc_rxed_any_close(conn))
	458	smc_close_stream_wait(smc, timeout);
	459	release_sock(sk);
18e537cd	460	cancel_delayed_work_sync(&conn->tx_work);
b38d7324	461	lock_sock(sk);
bbb96bf2 UB	462	if (sk->sk_state != SMC_APPCLOSEWAIT1)
bbb96bf2 UB	463	goto again;
b38d7324 UB	464	/* confirm close from peer */
	465	rc = smc_close_wr(conn);
	466	sk->sk_state = SMC_APPCLOSEWAIT2;
	467	break;
	468	case SMC_APPCLOSEWAIT2:
	469	case SMC_PEERFINCLOSEWAIT:
	470	case SMC_PEERCLOSEWAIT1:
	471	case SMC_PEERCLOSEWAIT2:
	472	case SMC_APPFINCLOSEWAIT:
	473	case SMC_PROCESSABORT:
	474	case SMC_PEERABORTWAIT:
	475	/* nothing to do, add tracing in future patch */
	476	break;
	477	}
	478
	479	if (old_state != sk->sk_state)
3163c507	480	sk->sk_state_change(sk);
b38d7324 UB	481	return rc;
b38d7324 UB	482	}
46c28dbd UB	483
	484	/* Initialize close properties on connection establishment. */
	485	void smc_close_init(struct smc_sock *smc)
	486	{
	487	INIT_WORK(&smc->conn.close_work, smc_close_passive_work);
	488	}