Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 767 insertions, 0 deletions

diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
new file mode 100644
index 0000000000..f10b37c147
--- /dev/null
+++ b/net/rxrpc/call_object.c
@@ -0,0 +1,767 @@
+// 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)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/circ_buf.h>
+#include <linux/spinlock_types.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
+	[RXRPC_CALL_UNINITIALISED]		= "Uninit  ",
+	[RXRPC_CALL_CLIENT_AWAIT_CONN]		= "ClWtConn",
+	[RXRPC_CALL_CLIENT_SEND_REQUEST]	= "ClSndReq",
+	[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_RECV_REQUEST]	= "SvRcvReq",
+	[RXRPC_CALL_SERVER_ACK_REQUEST]		= "SvAckReq",
+	[RXRPC_CALL_SERVER_SEND_REPLY]		= "SvSndRpl",
+	[RXRPC_CALL_SERVER_AWAIT_ACK]		= "SvAwtACK",
+	[RXRPC_CALL_COMPLETE]			= "Complete",
+};
+
+const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
+	[RXRPC_CALL_SUCCEEDED]			= "Complete",
+	[RXRPC_CALL_REMOTELY_ABORTED]		= "RmtAbort",
+	[RXRPC_CALL_LOCALLY_ABORTED]		= "LocAbort",
+	[RXRPC_CALL_LOCAL_ERROR]		= "LocError",
+	[RXRPC_CALL_NETWORK_ERROR]		= "NetError",
+};
+
+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_bh(&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_bh(&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);
+
+	_enter("%d", call->debug_id);
+
+	if (!__rxrpc_call_is_complete(call)) {
+		trace_rxrpc_timer_expired(call, jiffies);
+		rxrpc_poke_call(call, rxrpc_call_poke_timer);
+	}
+}
+
+void rxrpc_reduce_call_timer(struct rxrpc_call *call,
+			     unsigned long expire_at,
+			     unsigned long now,
+			     enum rxrpc_timer_trace why)
+{
+	trace_rxrpc_timer(call, why, now);
+	timer_reduce(&call->timer, expire_at);
+}
+
+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
+ */
+struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
+					      unsigned long user_call_ID)
+{
+	struct rxrpc_call *call;
+	struct rb_node *p;
+
+	_enter("%p,%lx", rx, user_call_ID);
+
+	read_lock(&rx->call_lock);
+
+	p = rx->calls.rb_node;
+	while (p) {
+		call = rb_entry(p, struct rxrpc_call, sock_node);
+
+		if (user_call_ID < call->user_call_ID)
+			p = p->rb_left;
+		else if (user_call_ID > call->user_call_ID)
+			p = p->rb_right;
+		else
+			goto found_extant_call;
+	}
+
+	read_unlock(&rx->call_lock);
+	_leave(" = NULL");
+	return NULL;
+
+found_extant_call:
+	rxrpc_get_call(call, rxrpc_call_get_sendmsg);
+	read_unlock(&rx->call_lock);
+	_leave(" = %p [%d]", call, refcount_read(&call->ref));
+	return call;
+}
+
+/*
+ * allocate a new call
+ */
+struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
+				    unsigned int debug_id)
+{
+	struct rxrpc_call *call;
+	struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
+
+	call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
+	if (!call)
+		return NULL;
+
+	mutex_init(&call->user_mutex);
+
+	/* Prevent lockdep reporting a deadlock false positive between the afs
+	 * filesystem and sys_sendmsg() via the mmap sem.
+	 */
+	if (rx->sk.sk_kern_sock)
+		lockdep_set_class(&call->user_mutex,
+				  &rxrpc_call_user_mutex_lock_class_key);
+
+	timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
+	INIT_WORK(&call->destroyer, rxrpc_destroy_call);
+	INIT_LIST_HEAD(&call->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);
+	INIT_LIST_HEAD(&call->tx_sendmsg);
+	INIT_LIST_HEAD(&call->tx_buffer);
+	skb_queue_head_init(&call->recvmsg_queue);
+	skb_queue_head_init(&call->rx_oos_queue);
+	init_waitqueue_head(&call->waitq);
+	spin_lock_init(&call->notify_lock);
+	spin_lock_init(&call->tx_lock);
+	refcount_set(&call->ref, 1);
+	call->debug_id = debug_id;
+	call->tx_total_len = -1;
+	call->next_rx_timo = 20 * HZ;
+	call->next_req_timo = 1 * HZ;
+	call->ackr_window = 1;
+	call->ackr_wtop = 1;
+
+	memset(&call->sock_node, 0xed, sizeof(call->sock_node));
+
+	call->rx_winsize = rxrpc_rx_window_size;
+	call->tx_winsize = 16;
+
+	if (RXRPC_TX_SMSS > 2190)
+		call->cong_cwnd = 2;
+	else if (RXRPC_TX_SMSS > 1095)
+		call->cong_cwnd = 3;
+	else
+		call->cong_cwnd = 4;
+	call->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
+
+	call->rxnet = rxnet;
+	call->rtt_avail = RXRPC_CALL_RTT_AVAIL_MASK;
+	atomic_inc(&rxnet->nr_calls);
+	return call;
+}
+
+/*
+ * 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);
+	now = ktime_get_real();
+	call->acks_latest_ts	= now;
+	call->cong_tstamp	= now;
+	call->dest_srx		= *srx;
+	call->interruptibility	= p->interruptibility;
+	call->tx_total_len	= p->tx_total_len;
+	call->key		= key_get(cp->key);
+	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 = min(msecs_to_jiffies(p->timeouts.normal), 1UL);
+	if (p->timeouts.idle)
+		call->next_req_timo = min(msecs_to_jiffies(p->timeouts.idle), 1UL);
+	if (p->timeouts.hard)
+		call->hard_timo = p->timeouts.hard * HZ;
+
+	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;
+}
+
+/*
+ * Initiate the call ack/resend/expiry timer.
+ */
+void rxrpc_start_call_timer(struct rxrpc_call *call)
+{
+	unsigned long now = jiffies;
+	unsigned long j = now + MAX_JIFFY_OFFSET;
+
+	call->delay_ack_at = j;
+	call->ack_lost_at = j;
+	call->resend_at = j;
+	call->ping_at = j;
+	call->keepalive_at = j;
+	call->expect_rx_by = j;
+	call->expect_req_by = j;
+	call->expect_term_by = j + call->hard_timo;
+	call->timer.expires = now;
+}
+
+/*
+ * 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)
+{
+	struct rxrpc_local *local = call->local;
+	int ret = -ENOMEM;
+
+	_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
+
+	call->peer = rxrpc_lookup_peer(local, &call->dest_srx, gfp);
+	if (!call->peer)
+		goto error;
+
+	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(&local->client_call_lock);
+	list_add_tail(&call->wait_link, &local->new_client_calls);
+	spin_unlock(&local->client_call_lock);
+	rxrpc_wake_up_io_thread(local);
+	return 0;
+
+error:
+	__set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
+	return ret;
+}
+
+/*
+ * Set up a call for the given parameters.
+ * - Called with the socket lock held, which it must release.
+ * - If it returns a call, the call's lock will need releasing by the caller.
+ */
+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)
+	__acquires(&call->user_mutex)
+{
+	struct rxrpc_call *call, *xcall;
+	struct rxrpc_net *rxnet;
+	struct semaphore *limiter;
+	struct rb_node *parent, **pp;
+	int ret;
+
+	_enter("%p,%lx", rx, p->user_call_ID);
+
+	limiter = rxrpc_get_call_slot(p, gfp);
+	if (!limiter) {
+		release_sock(&rx->sk);
+		return ERR_PTR(-ERESTARTSYS);
+	}
+
+	call = rxrpc_alloc_client_call(rx, srx, cp, p, gfp, debug_id);
+	if (IS_ERR(call)) {
+		release_sock(&rx->sk);
+		up(limiter);
+		_leave(" = %ld", PTR_ERR(call));
+		return call;
+	}
+
+	/* We need to protect a partially set up call against the user as we
+	 * will be acting outside the socket lock.
+	 */
+	mutex_lock(&call->user_mutex);
+
+	/* Publish the call, even though it is incompletely set up as yet */
+	write_lock(&rx->call_lock);
+
+	pp = &rx->calls.rb_node;
+	parent = NULL;
+	while (*pp) {
+		parent = *pp;
+		xcall = rb_entry(parent, struct rxrpc_call, sock_node);
+
+		if (p->user_call_ID < xcall->user_call_ID)
+			pp = &(*pp)->rb_left;
+		else if (p->user_call_ID > xcall->user_call_ID)
+			pp = &(*pp)->rb_right;
+		else
+			goto error_dup_user_ID;
+	}
+
+	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_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);
+
+	write_unlock(&rx->call_lock);
+
+	rxnet = call->rxnet;
+	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);
+
+	/* Set up or get a connection record and set the protocol parameters,
+	 * including channel number and call ID.
+	 */
+	ret = rxrpc_connect_call(call, gfp);
+	if (ret < 0)
+		goto error_attached_to_socket;
+
+	_leave(" = %p [new]", call);
+	return call;
+
+	/* We unexpectedly found the user ID in the list after taking
+	 * the call_lock.  This shouldn't happen unless the user races
+	 * with itself and tries to add the same user ID twice at the
+	 * same time in different threads.
+	 */
+error_dup_user_ID:
+	write_unlock(&rx->call_lock);
+	release_sock(&rx->sk);
+	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_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.
+ */
+void rxrpc_incoming_call(struct rxrpc_sock *rx,
+			 struct rxrpc_call *call,
+			 struct sk_buff *skb)
+{
+	struct rxrpc_connection *conn = call->conn;
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	u32 chan;
+
+	_enter(",%d", call->conn->debug_id);
+
+	rcu_assign_pointer(call->socket, rx);
+	call->call_id		= sp->hdr.callNumber;
+	call->dest_srx.srx_service = sp->hdr.serviceId;
+	call->cid		= sp->hdr.cid;
+	call->cong_tstamp	= skb->tstamp;
+
+	__set_bit(RXRPC_CALL_EXPOSED, &call->flags);
+	rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
+
+	spin_lock(&conn->state_lock);
+
+	switch (conn->state) {
+	case RXRPC_CONN_SERVICE_UNSECURED:
+	case RXRPC_CONN_SERVICE_CHALLENGING:
+		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_SECURING);
+		break;
+	case RXRPC_CONN_SERVICE:
+		rxrpc_set_call_state(call, RXRPC_CALL_SERVER_RECV_REQUEST);
+		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
+	 * interested in call_counter and can cope with a disagreement with the
+	 * call pointer).
+	 */
+	chan = sp->hdr.cid & RXRPC_CHANNELMASK;
+	conn->channels[chan].call_counter = call->call_id;
+	conn->channels[chan].call_id = call->call_id;
+	conn->channels[chan].call = call;
+	spin_unlock(&conn->state_lock);
+
+	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("");
+}
+
+/*
+ * Note the re-emergence of a call.
+ */
+void rxrpc_see_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
+{
+	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;
+}
+
+/*
+ * Note the addition of a ref on a call.
+ */
+void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
+{
+	int r;
+
+	__refcount_inc(&call->ref, &r);
+	trace_rxrpc_call(call->debug_id, r + 1, 0, why);
+}
+
+/*
+ * Clean up the Rx skb ring.
+ */
+static void rxrpc_cleanup_ring(struct rxrpc_call *call)
+{
+	rxrpc_purge_queue(&call->recvmsg_queue);
+	rxrpc_purge_queue(&call->rx_oos_queue);
+}
+
+/*
+ * Detach a call from its owning socket.
+ */
+void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
+{
+	struct rxrpc_connection *conn = call->conn;
+	bool put = false, putu = false;
+
+	_enter("{%d,%d}", call->debug_id, refcount_read(&call->ref));
+
+	trace_rxrpc_call(call->debug_id, refcount_read(&call->ref),
+			 call->flags, rxrpc_call_see_release);
+
+	if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
+		BUG();
+
+	rxrpc_put_call_slot(call);
+
+	/* Make sure we don't get any more notifications */
+	spin_lock(&rx->recvmsg_lock);
+
+	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;
+
+	spin_unlock(&rx->recvmsg_lock);
+	if (put)
+		rxrpc_put_call(call, rxrpc_call_put_unnotify);
+
+	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));
+		putu = true;
+	}
+
+	list_del(&call->sock_link);
+	write_unlock(&rx->call_lock);
+
+	_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
+
+	if (putu)
+		rxrpc_put_call(call, rxrpc_call_put_userid);
+
+	_leave("");
+}
+
+/*
+ * release all the calls associated with a socket
+ */
+void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
+{
+	struct rxrpc_call *call;
+
+	_enter("%p", rx);
+
+	while (!list_empty(&rx->to_be_accepted)) {
+		call = list_entry(rx->to_be_accepted.next,
+				  struct rxrpc_call, accept_link);
+		list_del(&call->accept_link);
+		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_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_release_sock);
+	}
+
+	_leave("");
+}
+
+/*
+ * release a call
+ */
+void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace why)
+{
+	struct rxrpc_net *rxnet = call->rxnet;
+	unsigned int debug_id = call->debug_id;
+	bool dead;
+	int r;
+
+	ASSERT(call != NULL);
+
+	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)) {
+			spin_lock(&rxnet->call_lock);
+			list_del_init(&call->link);
+			spin_unlock(&rxnet->call_lock);
+		}
+
+		rxrpc_cleanup_call(call);
+	}
+}
+
+/*
+ * Free up the call under 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 = READ_ONCE(call->rxnet);
+
+	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);
+	struct rxrpc_txbuf *txb;
+
+	del_timer_sync(&call->timer);
+
+	rxrpc_cleanup_ring(call);
+	while ((txb = list_first_entry_or_null(&call->tx_sendmsg,
+					       struct rxrpc_txbuf, call_link))) {
+		list_del(&txb->call_link);
+		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
+	}
+	while ((txb = list_first_entry_or_null(&call->tx_buffer,
+					       struct rxrpc_txbuf, call_link))) {
+		list_del(&txb->call_link);
+		rxrpc_put_txbuf(txb, rxrpc_txbuf_put_cleaned);
+	}
+
+	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)
+{
+	memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
+
+	ASSERTCMP(__rxrpc_call_state(call), ==, RXRPC_CALL_COMPLETE);
+	ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
+
+	del_timer(&call->timer);
+
+	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);
+}
+
+/*
+ * Make sure that all calls are gone from a network namespace.  To reach this
+ * point, any open UDP sockets in that namespace must have been closed, so any
+ * outstanding calls cannot be doing I/O.
+ */
+void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
+{
+	struct rxrpc_call *call;
+
+	_enter("");
+
+	if (!list_empty(&rxnet->calls)) {
+		spin_lock(&rxnet->call_lock);
+
+		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);
+
+			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);
+
+			spin_unlock(&rxnet->call_lock);
+			cond_resched();
+			spin_lock(&rxnet->call_lock);
+		}
+
+		spin_unlock(&rxnet->call_lock);
+	}
+
+	atomic_dec(&rxnet->nr_calls);
+	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
+}