[linux-2.6-block.git] / net / rxrpc / conn_object.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC virtual connection handler, common bits.
 *
 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include "ar-internal.h"

/*
 * Time till a connection expires after last use (in seconds).
 */
unsigned int __read_mostly rxrpc_connection_expiry = 10 * 60;
unsigned int __read_mostly rxrpc_closed_conn_expiry = 10;

static void rxrpc_destroy_connection(struct rcu_head *);

static void rxrpc_connection_timer(struct timer_list *timer)
{
	struct rxrpc_connection *conn =
		container_of(timer, struct rxrpc_connection, timer);

	rxrpc_queue_conn(conn);
}

/*
 * allocate a new connection
 */
struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
{
	struct rxrpc_connection *conn;

	_enter("");

	conn = kzalloc(sizeof(struct rxrpc_connection), gfp);
	if (conn) {
		INIT_LIST_HEAD(&conn->cache_link);
		spin_lock_init(&conn->channel_lock);
		INIT_LIST_HEAD(&conn->waiting_calls);
		timer_setup(&conn->timer, &rxrpc_connection_timer, 0);
		INIT_WORK(&conn->processor, &rxrpc_process_connection);
		INIT_LIST_HEAD(&conn->proc_link);
		INIT_LIST_HEAD(&conn->link);
		skb_queue_head_init(&conn->rx_queue);
		conn->security = &rxrpc_no_security;
		spin_lock_init(&conn->state_lock);
		conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
		conn->size_align = 4;
		conn->idle_timestamp = jiffies;
	}

	_leave(" = %p{%d}", conn, conn ? conn->debug_id : 0);
	return conn;
}

/*
 * Look up a connection in the cache by protocol parameters.
 *
 * If successful, a pointer to the connection is returned, but no ref is taken.
 * NULL is returned if there is no match.
 *
 * When searching for a service call, if we find a peer but no connection, we
 * return that through *_peer in case we need to create a new service call.
 *
 * The caller must be holding the RCU read lock.
 */
struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *local,
						   struct sk_buff *skb,
						   struct rxrpc_peer **_peer)
{
	struct rxrpc_connection *conn;
	struct rxrpc_conn_proto k;
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
	struct sockaddr_rxrpc srx;
	struct rxrpc_peer *peer;

	_enter(",%x", sp->hdr.cid & RXRPC_CIDMASK);

	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
		goto not_found;

	if (srx.transport.family != local->srx.transport.family &&
	    (srx.transport.family == AF_INET &&
	     local->srx.transport.family != AF_INET6)) {
		pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
				    srx.transport.family,
				    local->srx.transport.family);
		goto not_found;
	}

	k.epoch	= sp->hdr.epoch;
	k.cid	= sp->hdr.cid & RXRPC_CIDMASK;

	if (rxrpc_to_server(sp)) {
		/* We need to look up service connections by the full protocol
		 * parameter set.  We look up the peer first as an intermediate
		 * step and then the connection from the peer's tree.
		 */
		peer = rxrpc_lookup_peer_rcu(local, &srx);
		if (!peer)
			goto not_found;
		*_peer = peer;
		conn = rxrpc_find_service_conn_rcu(peer, skb);
		if (!conn || atomic_read(&conn->usage) == 0)
			goto not_found;
		_leave(" = %p", conn);
		return conn;
	} else {
		/* Look up client connections by connection ID alone as their
		 * IDs are unique for this machine.
		 */
		conn = idr_find(&rxrpc_client_conn_ids,
				sp->hdr.cid >> RXRPC_CIDSHIFT);
		if (!conn || atomic_read(&conn->usage) == 0) {
			_debug("no conn");
			goto not_found;
		}

		if (conn->proto.epoch != k.epoch ||
		    conn->params.local != local)
			goto not_found;

		peer = conn->params.peer;
		switch (srx.transport.family) {
		case AF_INET:
			if (peer->srx.transport.sin.sin_port !=
			    srx.transport.sin.sin_port ||
			    peer->srx.transport.sin.sin_addr.s_addr !=
			    srx.transport.sin.sin_addr.s_addr)
				goto not_found;
			break;
#ifdef CONFIG_AF_RXRPC_IPV6
		case AF_INET6:
			if (peer->srx.transport.sin6.sin6_port !=
			    srx.transport.sin6.sin6_port ||
			    memcmp(&peer->srx.transport.sin6.sin6_addr,
				   &srx.transport.sin6.sin6_addr,
				   sizeof(struct in6_addr)) != 0)
				goto not_found;
			break;
#endif
		default:
			BUG();
		}

		_leave(" = %p", conn);
		return conn;
	}

not_found:
	_leave(" = NULL");
	return NULL;
}

/*
 * Disconnect a call and clear any channel it occupies when that call
 * terminates.  The caller must hold the channel_lock and must release the
 * call's ref on the connection.
 */
void __rxrpc_disconnect_call(struct rxrpc_connection *conn,
			     struct rxrpc_call *call)
{
	struct rxrpc_channel *chan =
		&conn->channels[call->cid & RXRPC_CHANNELMASK];

	_enter("%d,%x", conn->debug_id, call->cid);

	if (rcu_access_pointer(chan->call) == call) {
		/* Save the result of the call so that we can repeat it if necessary
		 * through the channel, whilst disposing of the actual call record.
		 */
		trace_rxrpc_disconnect_call(call);
		switch (call->completion) {
		case RXRPC_CALL_SUCCEEDED:
			chan->last_seq = call->rx_hard_ack;
			chan->last_type = RXRPC_PACKET_TYPE_ACK;
			break;
		case RXRPC_CALL_LOCALLY_ABORTED:
			chan->last_abort = call->abort_code;
			chan->last_type = RXRPC_PACKET_TYPE_ABORT;
			break;
		default:
			chan->last_abort = RX_USER_ABORT;
			chan->last_type = RXRPC_PACKET_TYPE_ABORT;
			break;
		}

		/* Sync with rxrpc_conn_retransmit(). */
		smp_wmb();
		chan->last_call = chan->call_id;
		chan->call_id = chan->call_counter;

		rcu_assign_pointer(chan->call, NULL);
	}

	_leave("");
}

/*
 * Disconnect a call and clear any channel it occupies when that call
 * terminates.
 */
void rxrpc_disconnect_call(struct rxrpc_call *call)
{
	struct rxrpc_connection *conn = call->conn;

	call->peer->cong_cwnd = call->cong_cwnd;

	spin_lock_bh(&conn->params.peer->lock);
	hlist_del_rcu(&call->error_link);
	spin_unlock_bh(&conn->params.peer->lock);

	if (rxrpc_is_client_call(call))
		return rxrpc_disconnect_client_call(call);

	spin_lock(&conn->channel_lock);
	__rxrpc_disconnect_call(conn, call);
	spin_unlock(&conn->channel_lock);

	call->conn = NULL;
	conn->idle_timestamp = jiffies;
	rxrpc_put_connection(conn);
}

/*
 * Kill off a connection.
 */
void rxrpc_kill_connection(struct rxrpc_connection *conn)
{
	struct rxrpc_net *rxnet = conn->params.local->rxnet;

	ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
	       !rcu_access_pointer(conn->channels[1].call) &&
	       !rcu_access_pointer(conn->channels[2].call) &&
	       !rcu_access_pointer(conn->channels[3].call));
	ASSERT(list_empty(&conn->cache_link));

	write_lock(&rxnet->conn_lock);
	list_del_init(&conn->proc_link);
	write_unlock(&rxnet->conn_lock);

	/* Drain the Rx queue.  Note that even though we've unpublished, an
	 * incoming packet could still be being added to our Rx queue, so we
	 * will need to drain it again in the RCU cleanup handler.
	 */
	rxrpc_purge_queue(&conn->rx_queue);

	/* Leave final destruction to RCU.  The connection processor work item
	 * must carry a ref on the connection to prevent us getting here whilst
	 * it is queued or running.
	 */
	call_rcu(&conn->rcu, rxrpc_destroy_connection);
}

/*
 * Queue a connection's work processor, getting a ref to pass to the work
 * queue.
 */
bool rxrpc_queue_conn(struct rxrpc_connection *conn)
{
	const void *here = __builtin_return_address(0);
	int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
	if (n == 0)
		return false;
	if (rxrpc_queue_work(&conn->processor))
		trace_rxrpc_conn(conn, rxrpc_conn_queued, n + 1, here);
	else
		rxrpc_put_connection(conn);
	return true;
}

/*
 * Note the re-emergence of a connection.
 */
void rxrpc_see_connection(struct rxrpc_connection *conn)
{
	const void *here = __builtin_return_address(0);
	if (conn) {
		int n = atomic_read(&conn->usage);

		trace_rxrpc_conn(conn, rxrpc_conn_seen, n, here);
	}
}

/*
 * Get a ref on a connection.
 */
void rxrpc_get_connection(struct rxrpc_connection *conn)
{
	const void *here = __builtin_return_address(0);
	int n = atomic_inc_return(&conn->usage);

	trace_rxrpc_conn(conn, rxrpc_conn_got, n, here);
}

/*
 * Try to get a ref on a connection.
 */
struct rxrpc_connection *
rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
{
	const void *here = __builtin_return_address(0);

	if (conn) {
		int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
		if (n > 0)
			trace_rxrpc_conn(conn, rxrpc_conn_got, n + 1, here);
		else
			conn = NULL;
	}
	return conn;
}

/*
 * Set the service connection reap timer.
 */
static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
					 unsigned long reap_at)
{
	if (rxnet->live)
		timer_reduce(&rxnet->service_conn_reap_timer, reap_at);
}

/*
 * Release a service connection
 */
void rxrpc_put_service_conn(struct rxrpc_connection *conn)
{
	const void *here = __builtin_return_address(0);
	int n;

	n = atomic_dec_return(&conn->usage);
	trace_rxrpc_conn(conn, rxrpc_conn_put_service, n, here);
	ASSERTCMP(n, >=, 0);
	if (n == 1)
		rxrpc_set_service_reap_timer(conn->params.local->rxnet,
					     jiffies + rxrpc_connection_expiry);
}

/*
 * destroy a virtual connection
 */
static void rxrpc_destroy_connection(struct rcu_head *rcu)
{
	struct rxrpc_connection *conn =
		container_of(rcu, struct rxrpc_connection, rcu);

	_enter("{%d,u=%d}", conn->debug_id, atomic_read(&conn->usage));

	ASSERTCMP(atomic_read(&conn->usage), ==, 0);

	_net("DESTROY CONN %d", conn->debug_id);

	del_timer_sync(&conn->timer);
	rxrpc_purge_queue(&conn->rx_queue);

	conn->security->clear(conn);
	key_put(conn->params.key);
	key_put(conn->server_key);
	rxrpc_put_peer(conn->params.peer);

	if (atomic_dec_and_test(&conn->params.local->rxnet->nr_conns))
		wake_up_var(&conn->params.local->rxnet->nr_conns);
	rxrpc_put_local(conn->params.local);

	kfree(conn);
	_leave("");
}

/*
 * reap dead service connections
 */
void rxrpc_service_connection_reaper(struct work_struct *work)
{
	struct rxrpc_connection *conn, *_p;
	struct rxrpc_net *rxnet =
		container_of(work, struct rxrpc_net, service_conn_reaper);
	unsigned long expire_at, earliest, idle_timestamp, now;

	LIST_HEAD(graveyard);

	_enter("");

	now = jiffies;
	earliest = now + MAX_JIFFY_OFFSET;

	write_lock(&rxnet->conn_lock);
	list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
		ASSERTCMP(atomic_read(&conn->usage), >, 0);
		if (likely(atomic_read(&conn->usage) > 1))
			continue;
		if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
			continue;

		if (rxnet->live && !conn->params.local->dead) {
			idle_timestamp = READ_ONCE(conn->idle_timestamp);
			expire_at = idle_timestamp + rxrpc_connection_expiry * HZ;
			if (conn->params.local->service_closed)
				expire_at = idle_timestamp + rxrpc_closed_conn_expiry * HZ;

			_debug("reap CONN %d { u=%d,t=%ld }",
			       conn->debug_id, atomic_read(&conn->usage),
			       (long)expire_at - (long)now);

			if (time_before(now, expire_at)) {
				if (time_before(expire_at, earliest))
					earliest = expire_at;
				continue;
			}
		}

		/* The usage count sits at 1 whilst the object is unused on the
		 * list; we reduce that to 0 to make the object unavailable.
		 */
		if (atomic_cmpxchg(&conn->usage, 1, 0) != 1)
			continue;
		trace_rxrpc_conn(conn, rxrpc_conn_reap_service, 0, NULL);

		if (rxrpc_conn_is_client(conn))
			BUG();
		else
			rxrpc_unpublish_service_conn(conn);

		list_move_tail(&conn->link, &graveyard);
	}
	write_unlock(&rxnet->conn_lock);

	if (earliest != now + MAX_JIFFY_OFFSET) {
		_debug("reschedule reaper %ld", (long)earliest - (long)now);
		ASSERT(time_after(earliest, now));
		rxrpc_set_service_reap_timer(rxnet, earliest);
	}

	while (!list_empty(&graveyard)) {
		conn = list_entry(graveyard.next, struct rxrpc_connection,
				  link);
		list_del_init(&conn->link);

		ASSERTCMP(atomic_read(&conn->usage), ==, 0);
		rxrpc_kill_connection(conn);
	}

	_leave("");
}

/*
 * preemptively destroy all the service connection records rather than
 * waiting for them to time out
 */
void rxrpc_destroy_all_connections(struct rxrpc_net *rxnet)
{
	struct rxrpc_connection *conn, *_p;
	bool leak = false;

	_enter("");

	atomic_dec(&rxnet->nr_conns);
	rxrpc_destroy_all_client_connections(rxnet);

	del_timer_sync(&rxnet->service_conn_reap_timer);
	rxrpc_queue_work(&rxnet->service_conn_reaper);
	flush_workqueue(rxrpc_workqueue);

	write_lock(&rxnet->conn_lock);
	list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
		pr_err("AF_RXRPC: Leaked conn %p {%d}\n",
		       conn, atomic_read(&conn->usage));
		leak = true;
	}
	write_unlock(&rxnet->conn_lock);
	BUG_ON(leak);

	ASSERT(list_empty(&rxnet->conn_proc_list));

	/* We need to wait for the connections to be destroyed by RCU as they
	 * pin things that we still need to get rid of.
	 */
	wait_var_event(&rxnet->nr_conns, !atomic_read(&rxnet->nr_conns));
	_leave("");
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
45025bce	2	/* RxRPC virtual connection handler, common bits.
17926a79	3	*
45025bce	4	* Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
17926a79	5	* Written by David Howells (dhowells@redhat.com)
17926a79 DH	6	*/
17926a79 DH	7
9b6d5398 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9b6d5398 JP	9
17926a79	10	#include <linux/module.h>
5a0e3ad6	11	#include <linux/slab.h>
17926a79 DH	12	#include <linux/net.h>
17926a79 DH	13	#include <linux/skbuff.h>
17926a79 DH	14	#include "ar-internal.h"
17926a79 DH	15
5873c083 DH	16	/*
	17	* Time till a connection expires after last use (in seconds).
	18	*/
f859ab61 DH	19	unsigned int __read_mostly rxrpc_connection_expiry = 10 * 60;
f859ab61 DH	20	unsigned int __read_mostly rxrpc_closed_conn_expiry = 10;
5873c083	21
45025bce DH	22	static void rxrpc_destroy_connection(struct rcu_head *);
45025bce DH	23
3136ef49 DH	24	static void rxrpc_connection_timer(struct timer_list *timer)
	25	{
	26	struct rxrpc_connection *conn =
	27	container_of(timer, struct rxrpc_connection, timer);
	28
	29	rxrpc_queue_conn(conn);
	30	}
	31
17926a79 DH	32	/*
	33	* allocate a new connection
	34	*/
c6d2b8d7	35	struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
17926a79 DH	36	{
	37	struct rxrpc_connection *conn;
	38
	39	_enter("");
	40
	41	conn = kzalloc(sizeof(struct rxrpc_connection), gfp);
	42	if (conn) {
45025bce	43	INIT_LIST_HEAD(&conn->cache_link);
999b69f8	44	spin_lock_init(&conn->channel_lock);
45025bce	45	INIT_LIST_HEAD(&conn->waiting_calls);
3136ef49	46	timer_setup(&conn->timer, &rxrpc_connection_timer, 0);
17926a79	47	INIT_WORK(&conn->processor, &rxrpc_process_connection);
4d028b2c	48	INIT_LIST_HEAD(&conn->proc_link);
999b69f8	49	INIT_LIST_HEAD(&conn->link);
17926a79	50	skb_queue_head_init(&conn->rx_queue);
e0e4d82f	51	conn->security = &rxrpc_no_security;
17926a79	52	spin_lock_init(&conn->state_lock);
17926a79	53	conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
17926a79	54	conn->size_align = 4;
f51b4480	55	conn->idle_timestamp = jiffies;
17926a79 DH	56	}
17926a79 DH	57
16c61add	58	_leave(" = %p{%d}", conn, conn ? conn->debug_id : 0);
17926a79 DH	59	return conn;
	60	}
	61
17926a79	62	/*
8496af50 DH	63	* Look up a connection in the cache by protocol parameters.
	64	*
	65	* If successful, a pointer to the connection is returned, but no ref is taken.
	66	* NULL is returned if there is no match.
	67	*
0099dc58 DH	68	* When searching for a service call, if we find a peer but no connection, we
	69	* return that through *_peer in case we need to create a new service call.
	70	*
8496af50	71	* The caller must be holding the RCU read lock.
17926a79	72	*/
8496af50	73	struct rxrpc_connection rxrpc_find_connection_rcu(struct rxrpc_local local,
0099dc58 DH	74	struct sk_buff *skb,
0099dc58 DH	75	struct rxrpc_peer **_peer)
17926a79 DH	76	{
17926a79 DH	77	struct rxrpc_connection *conn;
1291e9d1	78	struct rxrpc_conn_proto k;
42886ffe	79	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
1291e9d1 DH	80	struct sockaddr_rxrpc srx;
1291e9d1 DH	81	struct rxrpc_peer *peer;
17926a79	82
8496af50	83	_enter(",%x", sp->hdr.cid & RXRPC_CIDMASK);
17926a79	84
5a790b73	85	if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
1291e9d1	86	goto not_found;
17926a79	87
46894a13 DH	88	if (srx.transport.family != local->srx.transport.family &&
	89	(srx.transport.family == AF_INET &&
	90	local->srx.transport.family != AF_INET6)) {
1291e9d1 DH	91	pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
	92	srx.transport.family,
	93	local->srx.transport.family);
	94	goto not_found;
	95	}
	96
	97	k.epoch = sp->hdr.epoch;
	98	k.cid = sp->hdr.cid & RXRPC_CIDMASK;
17926a79	99
dc71db34	100	if (rxrpc_to_server(sp)) {
1291e9d1 DH	101	/* We need to look up service connections by the full protocol
	102	* parameter set. We look up the peer first as an intermediate
	103	* step and then the connection from the peer's tree.
	104	*/
	105	peer = rxrpc_lookup_peer_rcu(local, &srx);
	106	if (!peer)
	107	goto not_found;
0099dc58	108	*_peer = peer;
8496af50 DH	109	conn = rxrpc_find_service_conn_rcu(peer, skb);
	110	if (!conn \|\| atomic_read(&conn->usage) == 0)
	111	goto not_found;
	112	_leave(" = %p", conn);
	113	return conn;
4a3388c8	114	} else {
8496af50 DH	115	/* Look up client connections by connection ID alone as their
	116	* IDs are unique for this machine.
	117	*/
1291e9d1	118	conn = idr_find(&rxrpc_client_conn_ids,
8496af50 DH	119	sp->hdr.cid >> RXRPC_CIDSHIFT);
	120	if (!conn \|\| atomic_read(&conn->usage) == 0) {
	121	_debug("no conn");
	122	goto not_found;
	123	}
	124
	125	if (conn->proto.epoch != k.epoch \|\|
1291e9d1 DH	126	conn->params.local != local)
	127	goto not_found;
	128
	129	peer = conn->params.peer;
	130	switch (srx.transport.family) {
	131	case AF_INET:
	132	if (peer->srx.transport.sin.sin_port !=
	133	srx.transport.sin.sin_port \|\|
	134	peer->srx.transport.sin.sin_addr.s_addr !=
	135	srx.transport.sin.sin_addr.s_addr)
	136	goto not_found;
	137	break;
d1912747	138	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	139	case AF_INET6:
	140	if (peer->srx.transport.sin6.sin6_port !=
	141	srx.transport.sin6.sin6_port \|\|
	142	memcmp(&peer->srx.transport.sin6.sin6_addr,
	143	&srx.transport.sin6.sin6_addr,
	144	sizeof(struct in6_addr)) != 0)
	145	goto not_found;
	146	break;
d1912747	147	#endif
1291e9d1 DH	148	default:
	149	BUG();
	150	}
	151
1291e9d1 DH	152	_leave(" = %p", conn);
1291e9d1 DH	153	return conn;
17926a79 DH	154	}
17926a79 DH	155
1291e9d1	156	not_found:
17926a79 DH	157	_leave(" = NULL");
17926a79 DH	158	return NULL;
17926a79 DH	159	}
17926a79 DH	160
999b69f8 DH	161	/*
999b69f8 DH	162	* Disconnect a call and clear any channel it occupies when that call
a1399f8b DH	163	* terminates. The caller must hold the channel_lock and must release the
a1399f8b DH	164	* call's ref on the connection.
999b69f8	165	*/
45025bce DH	166	void __rxrpc_disconnect_call(struct rxrpc_connection *conn,
45025bce DH	167	struct rxrpc_call *call)
999b69f8	168	{
01a90a45 DH	169	struct rxrpc_channel *chan =
01a90a45 DH	170	&conn->channels[call->cid & RXRPC_CHANNELMASK];
999b69f8	171
01a90a45	172	_enter("%d,%x", conn->debug_id, call->cid);
999b69f8	173
a1399f8b DH	174	if (rcu_access_pointer(chan->call) == call) {
	175	/* Save the result of the call so that we can repeat it if necessary
	176	* through the channel, whilst disposing of the actual call record.
	177	*/
b1d9f7fd	178	trace_rxrpc_disconnect_call(call);
17e9e23b DH	179	switch (call->completion) {
17e9e23b DH	180	case RXRPC_CALL_SUCCEEDED:
248f219c	181	chan->last_seq = call->rx_hard_ack;
18bfeba5	182	chan->last_type = RXRPC_PACKET_TYPE_ACK;
17e9e23b DH	183	break;
	184	case RXRPC_CALL_LOCALLY_ABORTED:
	185	chan->last_abort = call->abort_code;
	186	chan->last_type = RXRPC_PACKET_TYPE_ABORT;
	187	break;
	188	default:
	189	chan->last_abort = RX_USER_ABORT;
	190	chan->last_type = RXRPC_PACKET_TYPE_ABORT;
	191	break;
18bfeba5	192	}
17e9e23b	193
18bfeba5	194	/* Sync with rxrpc_conn_retransmit(). */
a1399f8b DH	195	smp_wmb();
	196	chan->last_call = chan->call_id;
	197	chan->call_id = chan->call_counter;
e653cfe4	198
a1399f8b	199	rcu_assign_pointer(chan->call, NULL);
999b69f8	200	}
e653cfe4	201
a1399f8b DH	202	_leave("");
	203	}
	204
	205	/*
	206	* Disconnect a call and clear any channel it occupies when that call
	207	* terminates.
	208	*/
	209	void rxrpc_disconnect_call(struct rxrpc_call *call)
	210	{
	211	struct rxrpc_connection *conn = call->conn;
	212
f7aec129 DH	213	call->peer->cong_cwnd = call->cong_cwnd;
f7aec129 DH	214
248f219c	215	spin_lock_bh(&conn->params.peer->lock);
f3344303	216	hlist_del_rcu(&call->error_link);
248f219c DH	217	spin_unlock_bh(&conn->params.peer->lock);
248f219c DH	218
45025bce DH	219	if (rxrpc_is_client_call(call))
	220	return rxrpc_disconnect_client_call(call);
	221
a1399f8b	222	spin_lock(&conn->channel_lock);
45025bce	223	__rxrpc_disconnect_call(conn, call);
e653cfe4 DH	224	spin_unlock(&conn->channel_lock);
	225
	226	call->conn = NULL;
f51b4480	227	conn->idle_timestamp = jiffies;
e653cfe4	228	rxrpc_put_connection(conn);
999b69f8 DH	229	}
999b69f8 DH	230
45025bce DH	231	/*
	232	* Kill off a connection.
	233	*/
	234	void rxrpc_kill_connection(struct rxrpc_connection *conn)
	235	{
2baec2c3 DH	236	struct rxrpc_net *rxnet = conn->params.local->rxnet;
2baec2c3 DH	237
45025bce DH	238	ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
	239	!rcu_access_pointer(conn->channels[1].call) &&
	240	!rcu_access_pointer(conn->channels[2].call) &&
	241	!rcu_access_pointer(conn->channels[3].call));
	242	ASSERT(list_empty(&conn->cache_link));
	243
2baec2c3	244	write_lock(&rxnet->conn_lock);
45025bce	245	list_del_init(&conn->proc_link);
2baec2c3	246	write_unlock(&rxnet->conn_lock);
45025bce DH	247
	248	/* Drain the Rx queue. Note that even though we've unpublished, an
	249	* incoming packet could still be being added to our Rx queue, so we
	250	* will need to drain it again in the RCU cleanup handler.
	251	*/
	252	rxrpc_purge_queue(&conn->rx_queue);
	253
	254	/* Leave final destruction to RCU. The connection processor work item
	255	* must carry a ref on the connection to prevent us getting here whilst
	256	* it is queued or running.
	257	*/
	258	call_rcu(&conn->rcu, rxrpc_destroy_connection);
	259	}
	260
17926a79	261	/*
363deeab DH	262	* Queue a connection's work processor, getting a ref to pass to the work
363deeab DH	263	* queue.
17926a79	264	*/
363deeab	265	bool rxrpc_queue_conn(struct rxrpc_connection *conn)
17926a79	266	{
363deeab	267	const void *here = __builtin_return_address(0);
bfc18e38	268	int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
363deeab DH	269	if (n == 0)
	270	return false;
	271	if (rxrpc_queue_work(&conn->processor))
	272	trace_rxrpc_conn(conn, rxrpc_conn_queued, n + 1, here);
	273	else
	274	rxrpc_put_connection(conn);
	275	return true;
	276	}
	277
	278	/*
	279	* Note the re-emergence of a connection.
	280	*/
	281	void rxrpc_see_connection(struct rxrpc_connection *conn)
	282	{
	283	const void *here = __builtin_return_address(0);
	284	if (conn) {
	285	int n = atomic_read(&conn->usage);
	286
	287	trace_rxrpc_conn(conn, rxrpc_conn_seen, n, here);
	288	}
	289	}
	290
	291	/*
	292	* Get a ref on a connection.
	293	*/
	294	void rxrpc_get_connection(struct rxrpc_connection *conn)
	295	{
	296	const void *here = __builtin_return_address(0);
	297	int n = atomic_inc_return(&conn->usage);
	298
	299	trace_rxrpc_conn(conn, rxrpc_conn_got, n, here);
	300	}
	301
	302	/*
	303	* Try to get a ref on a connection.
	304	*/
	305	struct rxrpc_connection *
	306	rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
	307	{
	308	const void *here = __builtin_return_address(0);
	309
	310	if (conn) {
bfc18e38	311	int n = atomic_fetch_add_unless(&conn->usage, 1, 0);
363deeab DH	312	if (n > 0)
	313	trace_rxrpc_conn(conn, rxrpc_conn_got, n + 1, here);
	314	else
	315	conn = NULL;
	316	}
	317	return conn;
	318	}
	319
3d18cbb7 DH	320	/*
	321	* Set the service connection reap timer.
	322	*/
	323	static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
	324	unsigned long reap_at)
	325	{
	326	if (rxnet->live)
	327	timer_reduce(&rxnet->service_conn_reap_timer, reap_at);
	328	}
	329
363deeab DH	330	/*
	331	* Release a service connection
	332	*/
	333	void rxrpc_put_service_conn(struct rxrpc_connection *conn)
	334	{
	335	const void *here = __builtin_return_address(0);
	336	int n;
	337
	338	n = atomic_dec_return(&conn->usage);
	339	trace_rxrpc_conn(conn, rxrpc_conn_put_service, n, here);
	340	ASSERTCMP(n, >=, 0);
3d18cbb7 DH	341	if (n == 1)
	342	rxrpc_set_service_reap_timer(conn->params.local->rxnet,
	343	jiffies + rxrpc_connection_expiry);
17926a79 DH	344	}
	345
	346	/*
	347	* destroy a virtual connection
	348	*/
dee46364	349	static void rxrpc_destroy_connection(struct rcu_head *rcu)
17926a79	350	{
dee46364 DH	351	struct rxrpc_connection *conn =
	352	container_of(rcu, struct rxrpc_connection, rcu);
	353
	354	_enter("{%d,u=%d}", conn->debug_id, atomic_read(&conn->usage));
17926a79 DH	355
	356	ASSERTCMP(atomic_read(&conn->usage), ==, 0);
	357
	358	_net("DESTROY CONN %d", conn->debug_id);
	359
3136ef49	360	del_timer_sync(&conn->timer);
17926a79 DH	361	rxrpc_purge_queue(&conn->rx_queue);
17926a79 DH	362
e0e4d82f	363	conn->security->clear(conn);
19ffa01c	364	key_put(conn->params.key);
e0e4d82f	365	key_put(conn->server_key);
aa390bbe	366	rxrpc_put_peer(conn->params.peer);
31f5f9a1 DH	367
31f5f9a1 DH	368	if (atomic_dec_and_test(&conn->params.local->rxnet->nr_conns))
5bb053be	369	wake_up_var(&conn->params.local->rxnet->nr_conns);
aa390bbe	370	rxrpc_put_local(conn->params.local);
e0e4d82f	371
17926a79 DH	372	kfree(conn);
	373	_leave("");
	374	}
	375
	376	/*
45025bce	377	* reap dead service connections
17926a79	378	*/
2baec2c3	379	void rxrpc_service_connection_reaper(struct work_struct *work)
17926a79 DH	380	{
17926a79 DH	381	struct rxrpc_connection conn, _p;
2baec2c3	382	struct rxrpc_net *rxnet =
3d18cbb7	383	container_of(work, struct rxrpc_net, service_conn_reaper);
f859ab61	384	unsigned long expire_at, earliest, idle_timestamp, now;
17926a79 DH	385
	386	LIST_HEAD(graveyard);
	387
	388	_enter("");
	389
f51b4480	390	now = jiffies;
f859ab61	391	earliest = now + MAX_JIFFY_OFFSET;
17926a79	392
2baec2c3 DH	393	write_lock(&rxnet->conn_lock);
2baec2c3 DH	394	list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
001c1122 DH	395	ASSERTCMP(atomic_read(&conn->usage), >, 0);
001c1122 DH	396	if (likely(atomic_read(&conn->usage) > 1))
17926a79	397	continue;
00e90712 DH	398	if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
00e90712 DH	399	continue;
17926a79	400
d12040b6	401	if (rxnet->live && !conn->params.local->dead) {
f859ab61 DH	402	idle_timestamp = READ_ONCE(conn->idle_timestamp);
	403	expire_at = idle_timestamp + rxrpc_connection_expiry * HZ;
	404	if (conn->params.local->service_closed)
	405	expire_at = idle_timestamp + rxrpc_closed_conn_expiry * HZ;
	406
	407	_debug("reap CONN %d { u=%d,t=%ld }",
	408	conn->debug_id, atomic_read(&conn->usage),
	409	(long)expire_at - (long)now);
	410
	411	if (time_before(now, expire_at)) {
	412	if (time_before(expire_at, earliest))
	413	earliest = expire_at;
	414	continue;
	415	}
17926a79	416	}
001c1122 DH	417
	418	/* The usage count sits at 1 whilst the object is unused on the
	419	* list; we reduce that to 0 to make the object unavailable.
	420	*/
	421	if (atomic_cmpxchg(&conn->usage, 1, 0) != 1)
	422	continue;
88f2a825	423	trace_rxrpc_conn(conn, rxrpc_conn_reap_service, 0, NULL);
001c1122 DH	424
001c1122 DH	425	if (rxrpc_conn_is_client(conn))
45025bce	426	BUG();
001c1122 DH	427	else
	428	rxrpc_unpublish_service_conn(conn);
	429
	430	list_move_tail(&conn->link, &graveyard);
17926a79	431	}
2baec2c3	432	write_unlock(&rxnet->conn_lock);
17926a79	433
f859ab61 DH	434	if (earliest != now + MAX_JIFFY_OFFSET) {
f859ab61 DH	435	_debug("reschedule reaper %ld", (long)earliest - (long)now);
f51b4480	436	ASSERT(time_after(earliest, now));
3d7682af	437	rxrpc_set_service_reap_timer(rxnet, earliest);
17926a79 DH	438	}
17926a79 DH	439
17926a79 DH	440	while (!list_empty(&graveyard)) {
	441	conn = list_entry(graveyard.next, struct rxrpc_connection,
	442	link);
	443	list_del_init(&conn->link);
	444
	445	ASSERTCMP(atomic_read(&conn->usage), ==, 0);
45025bce	446	rxrpc_kill_connection(conn);
17926a79 DH	447	}
	448
	449	_leave("");
	450	}
	451
	452	/*
45025bce DH	453	* preemptively destroy all the service connection records rather than
45025bce DH	454	* waiting for them to time out
17926a79	455	*/
2baec2c3	456	void rxrpc_destroy_all_connections(struct rxrpc_net *rxnet)
17926a79	457	{
dee46364 DH	458	struct rxrpc_connection conn, _p;
	459	bool leak = false;
	460
17926a79 DH	461	_enter("");
17926a79 DH	462
31f5f9a1	463	atomic_dec(&rxnet->nr_conns);
2baec2c3	464	rxrpc_destroy_all_client_connections(rxnet);
45025bce	465
3d18cbb7 DH	466	del_timer_sync(&rxnet->service_conn_reap_timer);
3d18cbb7 DH	467	rxrpc_queue_work(&rxnet->service_conn_reaper);
dee46364 DH	468	flush_workqueue(rxrpc_workqueue);
dee46364 DH	469
2baec2c3 DH	470	write_lock(&rxnet->conn_lock);
2baec2c3 DH	471	list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
dee46364 DH	472	pr_err("AF_RXRPC: Leaked conn %p {%d}\n",
	473	conn, atomic_read(&conn->usage));
	474	leak = true;
	475	}
2baec2c3	476	write_unlock(&rxnet->conn_lock);
dee46364 DH	477	BUG_ON(leak);
dee46364 DH	478
2baec2c3	479	ASSERT(list_empty(&rxnet->conn_proc_list));
17926a79	480
31f5f9a1 DH	481	/* We need to wait for the connections to be destroyed by RCU as they
	482	* pin things that we still need to get rid of.
	483	*/
5bb053be	484	wait_var_event(&rxnet->nr_conns, !atomic_read(&rxnet->nr_conns));
17926a79 DH	485	_leave("");
17926a79 DH	486	}