1 files changed, 377 insertions, 232 deletions

diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 8aa2937b069f..918f41d97a2f 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -1,12 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /* RxRPC individual remote procedure call handling
  *
  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -26,8 +22,6 @@ const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
 	[RXRPC_CALL_CLIENT_AWAIT_REPLY]		= "ClAwtRpl",
 	[RXRPC_CALL_CLIENT_RECV_REPLY]		= "ClRcvRpl",
 	[RXRPC_CALL_SERVER_PREALLOC]		= "SvPrealc",
-	[RXRPC_CALL_SERVER_SECURING]		= "SvSecure",
-	[RXRPC_CALL_SERVER_ACCEPTING]		= "SvAccept",
 	[RXRPC_CALL_SERVER_RECV_REQUEST]	= "SvRcvReq",
 	[RXRPC_CALL_SERVER_ACK_REQUEST]		= "SvAckReq",
 	[RXRPC_CALL_SERVER_SEND_REPLY]		= "SvSndRpl",
@@ -45,20 +39,45 @@ const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
 
 struct kmem_cache *rxrpc_call_jar;
 
+static DEFINE_SEMAPHORE(rxrpc_call_limiter, 1000);
+static DEFINE_SEMAPHORE(rxrpc_kernel_call_limiter, 1000);
+
+void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
+{
+	struct rxrpc_local *local = call->local;
+	bool busy;
+
+	if (!test_bit(RXRPC_CALL_DISCONNECTED, &call->flags)) {
+		spin_lock_irq(&local->lock);
+		busy = !list_empty(&call->attend_link);
+		trace_rxrpc_poke_call(call, busy, what);
+		if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
+			busy = true;
+		if (!busy) {
+			list_add_tail(&call->attend_link, &local->call_attend_q);
+		}
+		spin_unlock_irq(&local->lock);
+		if (!busy)
+			rxrpc_wake_up_io_thread(local);
+	}
+}
+
 static void rxrpc_call_timer_expired(struct timer_list *t)
 {
-	struct rxrpc_call *call = from_timer(call, t, timer);
+	struct rxrpc_call *call = timer_container_of(call, t, timer);
 
 	_enter("%d", call->debug_id);
 
-	if (call->state < RXRPC_CALL_COMPLETE) {
-		trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
-		rxrpc_queue_call(call);
+	if (!__rxrpc_call_is_complete(call)) {
+		trace_rxrpc_timer_expired(call);
+		rxrpc_poke_call(call, rxrpc_call_poke_timer);
 	}
 }
 
 static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
 
+static void rxrpc_destroy_call(struct work_struct *);
+
 /*
  * find an extant server call
  * - called in process context with IRQs enabled
@@ -90,9 +109,9 @@ struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
 	return NULL;
 
 found_extant_call:
-	rxrpc_get_call(call, rxrpc_call_got);
+	rxrpc_get_call(call, rxrpc_call_get_sendmsg);
 	read_unlock(&rx->call_lock);
-	_leave(" = %p [%d]", call, atomic_read(&call->usage));
+	_leave(" = %p [%d]", call, refcount_read(&call->ref));
 	return call;
 }
 
@@ -109,16 +128,6 @@ struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
 	if (!call)
 		return NULL;
 
-	call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
-				    sizeof(struct sk_buff *),
-				    gfp);
-	if (!call->rxtx_buffer)
-		goto nomem;
-
-	call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
-	if (!call->rxtx_annotations)
-		goto nomem_2;
-
 	mutex_init(&call->user_mutex);
 
 	/* Prevent lockdep reporting a deadlock false positive between the afs
@@ -129,66 +138,104 @@ struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
 				  &rxrpc_call_user_mutex_lock_class_key);
 
 	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
-	INIT_WORK(&call->processor, &rxrpc_process_call);
+	INIT_WORK(&call->destroyer, rxrpc_destroy_call);
 	INIT_LIST_HEAD(&call->link);
-	INIT_LIST_HEAD(&call->chan_wait_link);
+	INIT_LIST_HEAD(&call->wait_link);
 	INIT_LIST_HEAD(&call->accept_link);
 	INIT_LIST_HEAD(&call->recvmsg_link);
 	INIT_LIST_HEAD(&call->sock_link);
+	INIT_LIST_HEAD(&call->attend_link);
+	skb_queue_head_init(&call->recvmsg_queue);
+	skb_queue_head_init(&call->rx_queue);
+	skb_queue_head_init(&call->rx_oos_queue);
 	init_waitqueue_head(&call->waitq);
-	spin_lock_init(&call->lock);
 	spin_lock_init(&call->notify_lock);
-	spin_lock_init(&call->input_lock);
-	rwlock_init(&call->state_lock);
-	atomic_set(&call->usage, 1);
-	call->debug_id = debug_id;
-	call->tx_total_len = -1;
-	call->next_rx_timo = 20 * HZ;
-	call->next_req_timo = 1 * HZ;
+	refcount_set(&call->ref, 1);
+	call->debug_id		= debug_id;
+	call->tx_total_len	= -1;
+	call->tx_jumbo_max	= 1;
+	call->next_rx_timo	= 20 * HZ;
+	call->next_req_timo	= 1 * HZ;
+	call->ackr_window	= 1;
+	call->ackr_wtop		= 1;
+	call->delay_ack_at	= KTIME_MAX;
+	call->rack_timo_at	= KTIME_MAX;
+	call->ping_at		= KTIME_MAX;
+	call->keepalive_at	= KTIME_MAX;
+	call->expect_rx_by	= KTIME_MAX;
+	call->expect_req_by	= KTIME_MAX;
+	call->expect_term_by	= KTIME_MAX;
 
 	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
 
-	/* Leave space in the ring to handle a maxed-out jumbo packet */
 	call->rx_winsize = rxrpc_rx_window_size;
 	call->tx_winsize = 16;
-	call->rx_expect_next = 1;
 
-	call->cong_cwnd = 2;
-	call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
+	call->cong_cwnd = RXRPC_MIN_CWND;
+	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
+
+	rxrpc_call_init_rtt(call);
 
 	call->rxnet = rxnet;
+	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
 	atomic_inc(&rxnet->nr_calls);
 	return call;
-
-nomem_2:
-	kfree(call->rxtx_buffer);
-nomem:
-	kmem_cache_free(rxrpc_call_jar, call);
-	return NULL;
 }
 
 /*
  * Allocate a new client call.
  */
 static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
-						  struct sockaddr_rxrpc *srx,
+						  struct rxrpc_conn_parameters *cp,
+						  struct rxrpc_call_params *p,
 						  gfp_t gfp,
 						  unsigned int debug_id)
 {
 	struct rxrpc_call *call;
 	ktime_t now;
+	int ret;
 
 	_enter("");
 
 	call = rxrpc_alloc_call(rx, gfp, debug_id);
 	if (!call)
 		return ERR_PTR(-ENOMEM);
-	call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
-	call->service_id = srx->srx_service;
-	call->tx_phase = true;
 	now = ktime_get_real();
-	call->acks_latest_ts = now;
-	call->cong_tstamp = now;
+	call->acks_latest_ts	= now;
+	call->cong_tstamp	= now;
+	call->dest_srx		= cp->peer->srx;
+	call->dest_srx.srx_service = cp->service_id;
+	call->interruptibility	= p->interruptibility;
+	call->tx_total_len	= p->tx_total_len;
+	call->key		= key_get(cp->key);
+	call->peer		= rxrpc_get_peer(cp->peer, rxrpc_peer_get_call);
+	call->local		= rxrpc_get_local(cp->local, rxrpc_local_get_call);
+	call->security_level	= cp->security_level;
+	if (p->kernel)
+		__set_bit(RXRPC_CALL_KERNEL, &call->flags);
+	if (cp->upgrade)
+		__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
+	if (cp->exclusive)
+		__set_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
+
+	if (p->timeouts.normal)
+		call->next_rx_timo = umin(p->timeouts.normal, 1);
+	if (p->timeouts.idle)
+		call->next_req_timo = umin(p->timeouts.idle, 1);
+	if (p->timeouts.hard)
+		call->hard_timo = p->timeouts.hard;
+
+	ret = rxrpc_init_client_call_security(call);
+	if (ret < 0) {
+		rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, ret);
+		rxrpc_put_call(call, rxrpc_call_put_discard_error);
+		return ERR_PTR(ret);
+	}
+
+	rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_AWAIT_CONN);
+
+	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
+			 p->user_call_ID, rxrpc_call_new_client);
 
 	_leave(" = %p", call);
 	return call;
@@ -197,19 +244,72 @@ static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
 /*
  * Initiate the call ack/resend/expiry timer.
  */
-static void rxrpc_start_call_timer(struct rxrpc_call *call)
+void rxrpc_start_call_timer(struct rxrpc_call *call)
+{
+	if (call->hard_timo) {
+		ktime_t delay = ms_to_ktime(call->hard_timo * 1000);
+
+		call->expect_term_by = ktime_add(ktime_get_real(), delay);
+		trace_rxrpc_timer_set(call, delay, rxrpc_timer_trace_hard);
+	}
+	call->timer.expires = jiffies;
+}
+
+/*
+ * Wait for a call slot to become available.
+ */
+static struct semaphore *rxrpc_get_call_slot(struct rxrpc_call_params *p, gfp_t gfp)
+{
+	struct semaphore *limiter = &rxrpc_call_limiter;
+
+	if (p->kernel)
+		limiter = &rxrpc_kernel_call_limiter;
+	if (p->interruptibility == RXRPC_UNINTERRUPTIBLE) {
+		down(limiter);
+		return limiter;
+	}
+	return down_interruptible(limiter) < 0 ? NULL : limiter;
+}
+
+/*
+ * Release a call slot.
+ */
+static void rxrpc_put_call_slot(struct rxrpc_call *call)
+{
+	struct semaphore *limiter = &rxrpc_call_limiter;
+
+	if (test_bit(RXRPC_CALL_KERNEL, &call->flags))
+		limiter = &rxrpc_kernel_call_limiter;
+	up(limiter);
+}
+
+/*
+ * Start the process of connecting a call.  We obtain a peer and a connection
+ * bundle, but the actual association of a call with a connection is offloaded
+ * to the I/O thread to simplify locking.
+ */
+static int rxrpc_connect_call(struct rxrpc_call *call, gfp_t gfp)
 {
-	unsigned long now = jiffies;
-	unsigned long j = now + MAX_JIFFY_OFFSET;
-
-	call->ack_at = j;
-	call->ack_lost_at = j;
-	call->resend_at = j;
-	call->ping_at = j;
-	call->expect_rx_by = j;
-	call->expect_req_by = j;
-	call->expect_term_by = j;
-	call->timer.expires = now;
+	struct rxrpc_local *local = call->local;
+	int ret = -ENOMEM;
+
+	_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
+
+	ret = rxrpc_look_up_bundle(call, gfp);
+	if (ret < 0)
+		goto error;
+
+	trace_rxrpc_client(NULL, -1, rxrpc_client_queue_new_call);
+	rxrpc_get_call(call, rxrpc_call_get_io_thread);
+	spin_lock_irq(&local->client_call_lock);
+	list_add_tail(&call->wait_link, &local->new_client_calls);
+	spin_unlock_irq(&local->client_call_lock);
+	rxrpc_wake_up_io_thread(local);
+	return 0;
+
+error:
+	__set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
+	return ret;
 }
 
 /*
@@ -219,32 +319,39 @@ static void rxrpc_start_call_timer(struct rxrpc_call *call)
  */
 struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 					 struct rxrpc_conn_parameters *cp,
-					 struct sockaddr_rxrpc *srx,
 					 struct rxrpc_call_params *p,
 					 gfp_t gfp,
 					 unsigned int debug_id)
-	__releases(&rx->sk.sk_lock.slock)
+	__releases(&rx->sk.sk_lock)
 	__acquires(&call->user_mutex)
 {
 	struct rxrpc_call *call, *xcall;
 	struct rxrpc_net *rxnet;
+	struct semaphore *limiter;
 	struct rb_node *parent, **pp;
-	const void *here = __builtin_return_address(0);
 	int ret;
 
 	_enter("%p,%lx", rx, p->user_call_ID);
 
-	call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
+	if (WARN_ON_ONCE(!cp->peer)) {
+		release_sock(&rx->sk);
+		return ERR_PTR(-EIO);
+	}
+
+	limiter = rxrpc_get_call_slot(p, gfp);
+	if (!limiter) {
+		release_sock(&rx->sk);
+		return ERR_PTR(-ERESTARTSYS);
+	}
+
+	call = rxrpc_alloc_client_call(rx, cp, p, gfp, debug_id);
 	if (IS_ERR(call)) {
 		release_sock(&rx->sk);
+		up(limiter);
 		_leave(" = %ld", PTR_ERR(call));
 		return call;
 	}
 
-	call->tx_total_len = p->tx_total_len;
-	trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
-			 here, (const void *)p->user_call_ID);
-
 	/* We need to protect a partially set up call against the user as we
 	 * will be acting outside the socket lock.
 	 */
@@ -270,7 +377,7 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 	rcu_assign_pointer(call->socket, rx);
 	call->user_call_ID = p->user_call_ID;
 	__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
-	rxrpc_get_call(call, rxrpc_call_got_userid);
+	rxrpc_get_call(call, rxrpc_call_get_userid);
 	rb_link_node(&call->sock_node, parent, pp);
 	rb_insert_color(&call->sock_node, &rx->calls);
 	list_add(&call->sock_link, &rx->sock_calls);
@@ -278,9 +385,9 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 	write_unlock(&rx->call_lock);
 
 	rxnet = call->rxnet;
-	write_lock(&rxnet->call_lock);
-	list_add_tail(&call->link, &rxnet->calls);
-	write_unlock(&rxnet->call_lock);
+	spin_lock(&rxnet->call_lock);
+	list_add_tail_rcu(&call->link, &rxnet->calls);
+	spin_unlock(&rxnet->call_lock);
 
 	/* From this point on, the call is protected by its own lock. */
 	release_sock(&rx->sk);
@@ -288,16 +395,9 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 	/* Set up or get a connection record and set the protocol parameters,
 	 * including channel number and call ID.
 	 */
-	ret = rxrpc_connect_call(rx, call, cp, srx, gfp);
+	ret = rxrpc_connect_call(call, gfp);
 	if (ret < 0)
-		goto error;
-
-	trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
-			 here, NULL);
-
-	rxrpc_start_call_timer(call);
-
-	_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
+		goto error_attached_to_socket;
 
 	_leave(" = %p [new]", call);
 	return call;
@@ -310,23 +410,30 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 error_dup_user_ID:
 	write_unlock(&rx->call_lock);
 	release_sock(&rx->sk);
-	ret = -EEXIST;
-
-error:
-	__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
-				    RX_CALL_DEAD, ret);
-	trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
-			 here, ERR_PTR(ret));
-	rxrpc_release_call(rx, call);
+	rxrpc_prefail_call(call, RXRPC_CALL_LOCAL_ERROR, -EEXIST);
+	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), 0,
+			 rxrpc_call_see_userid_exists);
 	mutex_unlock(&call->user_mutex);
-	rxrpc_put_call(call, rxrpc_call_put);
-	_leave(" = %d", ret);
-	return ERR_PTR(ret);
+	rxrpc_put_call(call, rxrpc_call_put_userid_exists);
+	_leave(" = -EEXIST");
+	return ERR_PTR(-EEXIST);
+
+	/* We got an error, but the call is attached to the socket and is in
+	 * need of release.  However, we might now race with recvmsg() when it
+	 * completion notifies the socket.  Return 0 from sys_sendmsg() and
+	 * leave the error to recvmsg() to deal with.
+	 */
+error_attached_to_socket:
+	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref), ret,
+			 rxrpc_call_see_connect_failed);
+	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
+	_leave(" = c=%08x [err]", call->debug_id);
+	return call;
 }
 
 /*
  * Set up an incoming call.  call->conn points to the connection.
- * This is called in BH context and isn't allowed to fail.
+ * This is called with interrupts disabled and isn't allowed to fail.
  */
 void rxrpc_incoming_call(struct rxrpc_sock *rx,
 			 struct rxrpc_call *call,
@@ -340,13 +447,33 @@ void rxrpc_incoming_call(struct rxrpc_sock *rx,
 
 	rcu_assign_pointer(call->socket, rx);
 	call->call_id		= sp->hdr.callNumber;
-	call->service_id	= sp->hdr.serviceId;
+	call->dest_srx.srx_service = sp->hdr.serviceId;
 	call->cid		= sp->hdr.cid;
-	call->state		= RXRPC_CALL_SERVER_ACCEPTING;
-	if (sp->hdr.securityIndex > 0)
-		call->state	= RXRPC_CALL_SERVER_SECURING;
 	call->cong_tstamp	= skb->tstamp;
 
+	__set_bit(RXRPC_CALL_EXPOSED, &call->flags);
+	rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
+
+	spin_lock(&conn->state_lock);
+
+	switch (conn->state) {
+	case RXRPC_CONN_SERVICE_UNSECURED:
+	case RXRPC_CONN_SERVICE_CHALLENGING:
+		__set_bit(RXRPC_CALL_CONN_CHALLENGING, &call->flags);
+		break;
+	case RXRPC_CONN_SERVICE:
+		break;
+
+	case RXRPC_CONN_ABORTED:
+		rxrpc_set_call_completion(call, conn->completion,
+					  conn->abort_code, conn->error);
+		break;
+	default:
+		BUG();
+	}
+
+	rxrpc_get_call(call, rxrpc_call_get_io_thread);
+
 	/* Set the channel for this call.  We don't get channel_lock as we're
 	 * only defending against the data_ready handler (which we're called
 	 * from) and the RESPONSE packet parser (which is only really
@@ -356,71 +483,76 @@ void rxrpc_incoming_call(struct rxrpc_sock *rx,
 	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
 	conn->channels[chan].call_counter = call->call_id;
 	conn->channels[chan].call_id = call->call_id;
-	rcu_assign_pointer(conn->channels[chan].call, call);
+	conn->channels[chan].call = call;
+	spin_unlock(&conn->state_lock);
 
-	spin_lock(&conn->params.peer->lock);
-	hlist_add_head_rcu(&call->error_link, &conn->params.peer->error_targets);
-	spin_unlock(&conn->params.peer->lock);
-
-	_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
+	spin_lock(&conn->peer->lock);
+	hlist_add_head(&call->error_link, &conn->peer->error_targets);
+	spin_unlock(&conn->peer->lock);
 
 	rxrpc_start_call_timer(call);
 	_leave("");
 }
 
 /*
- * Queue a call's work processor, getting a ref to pass to the work queue.
+ * Note the re-emergence of a call.
  */
-bool rxrpc_queue_call(struct rxrpc_call *call)
+void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 {
-	const void *here = __builtin_return_address(0);
-	int n = atomic_fetch_add_unless(&call->usage, 1, 0);
-	if (n == 0)
-		return false;
-	if (rxrpc_queue_work(&call->processor))
-		trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
-	else
-		rxrpc_put_call(call, rxrpc_call_put_noqueue);
-	return true;
+	if (call) {
+		int r = refcount_read(&call->ref);
+
+		trace_rxrpc_call(call->debug_id, r, 0, why);
+	}
+}
+
+struct rxrpc_call *rxrpc_try_get_call(struct rxrpc_call *call,
+				      enum rxrpc_call_trace why)
+{
+	int r;
+
+	if (!call || !__refcount_inc_not_zero(&call->ref, &r))
+		return NULL;
+	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
+	return call;
 }
 
 /*
- * Queue a call's work processor, passing the callers ref to the work queue.
+ * Note the addition of a ref on a call.
  */
-bool __rxrpc_queue_call(struct rxrpc_call *call)
+void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 {
-	const void *here = __builtin_return_address(0);
-	int n = atomic_read(&call->usage);
-	ASSERTCMP(n, >=, 1);
-	if (rxrpc_queue_work(&call->processor))
-		trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
-	else
-		rxrpc_put_call(call, rxrpc_call_put_noqueue);
-	return true;
+	int r;
+
+	__refcount_inc(&call->ref, &r);
+	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
 }
 
 /*
- * Note the re-emergence of a call.
+ * Clean up the transmission buffers.
  */
-void rxrpc_see_call(struct rxrpc_call *call)
+static void rxrpc_cleanup_tx_buffers(struct rxrpc_call *call)
 {
-	const void *here = __builtin_return_address(0);
-	if (call) {
-		int n = atomic_read(&call->usage);
-
-		trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
+	struct rxrpc_txqueue *tq, *next;
+
+	for (tq = call->tx_queue; tq; tq = next) {
+		next = tq->next;
+		for (int i = 0; i < RXRPC_NR_TXQUEUE; i++)
+			if (tq->bufs[i])
+				rxrpc_put_txbuf(tq->bufs[i], rxrpc_txbuf_put_cleaned);
+		trace_rxrpc_tq(call, tq, 0, rxrpc_tq_cleaned);
+		kfree(tq);
 	}
 }
 
 /*
- * Note the addition of a ref on a call.
+ * Clean up the receive buffers.
  */
-void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
+static void rxrpc_cleanup_rx_buffers(struct rxrpc_call *call)
 {
-	const void *here = __builtin_return_address(0);
-	int n = atomic_inc_return(&call->usage);
-
-	trace_rxrpc_call(call, op, n, here, NULL);
+	rxrpc_purge_queue(&call->recvmsg_queue);
+	rxrpc_purge_queue(&call->rx_queue);
+	rxrpc_purge_queue(&call->rx_oos_queue);
 }
 
 /*
@@ -428,49 +560,33 @@ void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
  */
 void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 {
-	const void *here = __builtin_return_address(0);
 	struct rxrpc_connection *conn = call->conn;
-	bool put = false;
-	int i;
-
-	_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
+	bool putu = false;
 
-	trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
-			 here, (const void *)call->flags);
+	_enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
 
-	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
+	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
+			 call->flags, rxrpc_call_see_release);
 
-	spin_lock_bh(&call->lock);
 	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
 		BUG();
-	spin_unlock_bh(&call->lock);
-
-	del_timer_sync(&call->timer);
 
-	/* Make sure we don't get any more notifications */
-	write_lock_bh(&rx->recvmsg_lock);
+	rxrpc_put_call_slot(call);
 
-	if (!list_empty(&call->recvmsg_link)) {
-		_debug("unlinking once-pending call %p { e=%lx f=%lx }",
-		       call, call->events, call->flags);
-		list_del(&call->recvmsg_link);
-		put = true;
-	}
-
-	/* list_empty() must return false in rxrpc_notify_socket() */
-	call->recvmsg_link.next = NULL;
-	call->recvmsg_link.prev = NULL;
-
-	write_unlock_bh(&rx->recvmsg_lock);
-	if (put)
-		rxrpc_put_call(call, rxrpc_call_put);
+	/* Note that at this point, the call may still be on or may have been
+	 * added back on to the socket receive queue.  recvmsg() must discard
+	 * released calls.  The CALL_RELEASED flag should prevent further
+	 * notifications.
+	 */
+	spin_lock_irq(&rx->recvmsg_lock);
+	spin_unlock_irq(&rx->recvmsg_lock);
 
 	write_lock(&rx->call_lock);
 
 	if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
 		rb_erase(&call->sock_node, &rx->calls);
 		memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
-		rxrpc_put_call(call, rxrpc_call_put_userid);
+		putu = true;
 	}
 
 	list_del(&call->sock_link);
@@ -478,15 +594,8 @@ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
 
 	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
 
-	if (conn)
-		rxrpc_disconnect_call(call);
-
-	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
-		rxrpc_free_skb(call->rxtx_buffer[i],
-			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
-				rxrpc_skb_rx_cleaned));
-		call->rxtx_buffer[i] = NULL;
-	}
+	if (putu)
+		rxrpc_put_call(call, rxrpc_call_put_userid);
 
 	_leave("");
 }
@@ -504,18 +613,25 @@ void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 		call = list_entry(rx->to_be_accepted.next,
 				  struct rxrpc_call, accept_link);
 		list_del(&call->accept_link);
-		rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
-		rxrpc_put_call(call, rxrpc_call_put);
+		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
+				    rxrpc_abort_call_sock_release_tba);
+		rxrpc_put_call(call, rxrpc_call_put_release_sock_tba);
 	}
 
 	while (!list_empty(&rx->sock_calls)) {
 		call = list_entry(rx->sock_calls.next,
 				  struct rxrpc_call, sock_link);
-		rxrpc_get_call(call, rxrpc_call_got);
-		rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
-		rxrpc_send_abort_packet(call);
+		rxrpc_get_call(call, rxrpc_call_get_release_sock);
+		rxrpc_propose_abort(call, RX_CALL_DEAD, -ECONNRESET,
+				    rxrpc_abort_call_sock_release);
 		rxrpc_release_call(rx, call);
-		rxrpc_put_call(call, rxrpc_call_put);
+		rxrpc_put_call(call, rxrpc_call_put_release_sock);
+	}
+
+	while ((call = list_first_entry_or_null(&rx->recvmsg_q,
+						struct rxrpc_call, recvmsg_link))) {
+		list_del_init(&call->recvmsg_link);
+		rxrpc_put_call(call, rxrpc_call_put_release_recvmsg_q);
 	}
 
 	_leave("");
@@ -524,25 +640,24 @@ void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
 /*
  * release a call
  */
-void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
+void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
 {
 	struct rxrpc_net *rxnet = call->rxnet;
-	const void *here = __builtin_return_address(0);
-	int n;
+	unsigned int debug_id = call->debug_id;
+	bool dead;
+	int r;
 
 	ASSERT(call != NULL);
 
-	n = atomic_dec_return(&call->usage);
-	trace_rxrpc_call(call, op, n, here, NULL);
-	ASSERTCMP(n, >=, 0);
-	if (n == 0) {
-		_debug("call %d dead", call->debug_id);
-		ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
+	dead = __refcount_dec_and_test(&call->ref, &r);
+	trace_rxrpc_call(debug_id, r - 1, 0, why);
+	if (dead) {
+		ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 
 		if (!list_empty(&call->link)) {
-			write_lock(&rxnet->call_lock);
+			spin_lock(&rxnet->call_lock);
 			list_del_init(&call->link);
-			write_unlock(&rxnet->call_lock);
+			spin_unlock(&rxnet->call_lock);
 		}
 
 		rxrpc_cleanup_call(call);
@@ -550,47 +665,57 @@ void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
 }
 
 /*
- * Final call destruction under RCU.
+ * Free up the call under RCU.
  */
-static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
+static void rxrpc_rcu_free_call(struct rcu_head *rcu)
 {
 	struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
-	struct rxrpc_net *rxnet = call->rxnet;
+	struct rxrpc_net *rxnet = READ_ONCE(call->rxnet);
 
-	rxrpc_put_peer(call->peer);
-	kfree(call->rxtx_buffer);
-	kfree(call->rxtx_annotations);
 	kmem_cache_free(rxrpc_call_jar, call);
 	if (atomic_dec_and_test(&rxnet->nr_calls))
 		wake_up_var(&rxnet->nr_calls);
 }
 
 /*
+ * Final call destruction - but must be done in process context.
+ */
+static void rxrpc_destroy_call(struct work_struct *work)
+{
+	struct rxrpc_call *call = container_of(work, struct rxrpc_call, destroyer);
+
+	timer_delete_sync(&call->timer);
+
+	rxrpc_cleanup_tx_buffers(call);
+	rxrpc_cleanup_rx_buffers(call);
+	rxrpc_put_txbuf(call->tx_pending, rxrpc_txbuf_put_cleaned);
+	rxrpc_put_connection(call->conn, rxrpc_conn_put_call);
+	rxrpc_deactivate_bundle(call->bundle);
+	rxrpc_put_bundle(call->bundle, rxrpc_bundle_put_call);
+	rxrpc_put_peer(call->peer, rxrpc_peer_put_call);
+	rxrpc_put_local(call->local, rxrpc_local_put_call);
+	call_rcu(&call->rcu, rxrpc_rcu_free_call);
+}
+
+/*
  * clean up a call
  */
 void rxrpc_cleanup_call(struct rxrpc_call *call)
 {
-	int i;
-
-	_net("DESTROY CALL %d", call->debug_id);
-
 	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
 
-	del_timer_sync(&call->timer);
-
-	ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
+	ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
 	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
-	ASSERTCMP(call->conn, ==, NULL);
 
-	/* Clean up the Rx/Tx buffer */
-	for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
-		rxrpc_free_skb(call->rxtx_buffer[i],
-			       (call->tx_phase ? rxrpc_skb_tx_cleaned :
-				rxrpc_skb_rx_cleaned));
+	timer_delete(&call->timer);
 
-	rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
-
-	call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
+	if (rcu_read_lock_held())
+		/* Can't use the rxrpc workqueue as we need to cancel/flush
+		 * something that may be running/waiting there.
+		 */
+		schedule_work(&call->destroyer);
+	else
+		rxrpc_destroy_call(&call->destroyer);
 }
 
 /*
@@ -604,30 +729,50 @@ void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 
 	_enter("");
 
-	if (list_empty(&rxnet->calls))
-		return;
+	if (!list_empty(&rxnet->calls)) {
+		spin_lock(&rxnet->call_lock);
 
-	write_lock(&rxnet->call_lock);
+		while (!list_empty(&rxnet->calls)) {
+			call = list_entry(rxnet->calls.next,
+					  struct rxrpc_call, link);
+			_debug("Zapping call %p", call);
 
-	while (!list_empty(&rxnet->calls)) {
-		call = list_entry(rxnet->calls.next, struct rxrpc_call, link);
-		_debug("Zapping call %p", call);
+			rxrpc_see_call(call, rxrpc_call_see_zap);
+			list_del_init(&call->link);
 
-		rxrpc_see_call(call);
-		list_del_init(&call->link);
+			pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
+			       call, refcount_read(&call->ref),
+			       rxrpc_call_states[__rxrpc_call_state(call)],
+			       call->flags, call->events);
 
-		pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
-		       call, atomic_read(&call->usage),
-		       rxrpc_call_states[call->state],
-		       call->flags, call->events);
+			spin_unlock(&rxnet->call_lock);
+			cond_resched();
+			spin_lock(&rxnet->call_lock);
+		}
 
-		write_unlock(&rxnet->call_lock);
-		cond_resched();
-		write_lock(&rxnet->call_lock);
+		spin_unlock(&rxnet->call_lock);
 	}
 
-	write_unlock(&rxnet->call_lock);
-
 	atomic_dec(&rxnet->nr_calls);
 	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 }
+
+/**
+ * rxrpc_kernel_query_call_security - Query call's security parameters
+ * @call: The call to query
+ * @_service_id: Where to return the service ID
+ * @_enctype: Where to return the "encoding type"
+ *
+ * This queries the security parameters of a call, setting *@_service_id and
+ * *@_enctype and returning the security class.
+ *
+ * Return: The security class protocol number.
+ */
+u8 rxrpc_kernel_query_call_security(struct rxrpc_call *call,
+				    u16 *_service_id, u32 *_enctype)
+{
+	*_service_id = call->dest_srx.srx_service;
+	*_enctype = call->security_enctype;
+	return call->security_ix;
+}
+EXPORT_SYMBOL(rxrpc_kernel_query_call_security);