9 files changed, 281 insertions, 119 deletions

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index 7dcbca3bf828..7ae88958051f 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -157,7 +157,7 @@ static int afs_record_cm_probe(struct afs_call *call, struct afs_server *server)
 	_enter("");
 
 	if (test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags) &&
-	    !test_bit(AFS_SERVER_FL_PROBING, &server->flags)) {
+	    !afs_is_probing_server(server)) {
 		if (server->cm_epoch == call->epoch)
 			return 0;
 
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c
index d37d78eb84bd..442b5e7944ff 100644
--- a/fs/afs/fs_probe.c
+++ b/fs/afs/fs_probe.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 /* AFS fileserver probing
  *
- * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2018, 2020 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  */
 
@@ -11,14 +11,83 @@
 #include "internal.h"
 #include "protocol_yfs.h"
 
-static bool afs_fs_probe_done(struct afs_server *server)
+static unsigned int afs_fs_probe_fast_poll_interval = 30 * HZ;
+static unsigned int afs_fs_probe_slow_poll_interval = 5 * 60 * HZ;
+
+/*
+ * Start the probe polling timer.  We have to supply it with an inc on the
+ * outstanding server count.
+ */
+static void afs_schedule_fs_probe(struct afs_net *net,
+				  struct afs_server *server, bool fast)
+{
+	unsigned long atj;
+
+	if (!net->live)
+		return;
+
+	atj = server->probed_at;
+	atj += fast ? afs_fs_probe_fast_poll_interval : afs_fs_probe_slow_poll_interval;
+
+	afs_inc_servers_outstanding(net);
+	if (timer_reduce(&net->fs_probe_timer, atj))
+		afs_dec_servers_outstanding(net);
+}
+
+/*
+ * Handle the completion of a set of probes.
+ */
+static void afs_finished_fs_probe(struct afs_net *net, struct afs_server *server)
+{
+	bool responded = server->probe.responded;
+
+	write_seqlock(&net->fs_lock);
+	if (responded)
+		list_add_tail(&server->probe_link, &net->fs_probe_slow);
+	else
+		list_add_tail(&server->probe_link, &net->fs_probe_fast);
+	write_sequnlock(&net->fs_lock);
+
+	afs_schedule_fs_probe(net, server, !responded);
+}
+
+/*
+ * Handle the completion of a probe.
+ */
+static void afs_done_one_fs_probe(struct afs_net *net, struct afs_server *server)
+{
+	_enter("");
+
+	if (atomic_dec_and_test(&server->probe_outstanding))
+		afs_finished_fs_probe(net, server);
+
+	wake_up_all(&server->probe_wq);
+}
+
+/*
+ * Handle inability to send a probe due to ENOMEM when trying to allocate a
+ * call struct.
+ */
+static void afs_fs_probe_not_done(struct afs_net *net,
+				  struct afs_server *server,
+				  struct afs_addr_cursor *ac)
 {
-	if (!atomic_dec_and_test(&server->probe_outstanding))
-		return false;
+	struct afs_addr_list *alist = ac->alist;
+	unsigned int index = ac->index;
+
+	_enter("");
 
-	clear_bit_unlock(AFS_SERVER_FL_PROBING, &server->flags);
-	wake_up_bit(&server->flags, AFS_SERVER_FL_PROBING);
-	return true;
+	trace_afs_io_error(0, -ENOMEM, afs_io_error_fs_probe_fail);
+	spin_lock(&server->probe_lock);
+
+	server->probe.local_failure = true;
+	if (server->probe.error == 0)
+		server->probe.error = -ENOMEM;
+
+	set_bit(index, &alist->failed);
+
+	spin_unlock(&server->probe_lock);
+	return afs_done_one_fs_probe(net, server);
 }
 
 /*
@@ -29,10 +98,8 @@ void afs_fileserver_probe_result(struct afs_call *call)
 {
 	struct afs_addr_list *alist = call->alist;
 	struct afs_server *server = call->server;
-	unsigned int server_index = call->server_index;
 	unsigned int index = call->addr_ix;
 	unsigned int rtt_us = 0;
-	bool have_result = false;
 	int ret = call->error;
 
 	_enter("%pU,%u", &server->uuid, index);
@@ -51,8 +118,9 @@ void afs_fileserver_probe_result(struct afs_call *call)
 		goto responded;
 	case -ENOMEM:
 	case -ENONET:
+		clear_bit(index, &alist->responded);
 		server->probe.local_failure = true;
-		afs_io_error(call, afs_io_error_fs_probe_fail);
+		trace_afs_io_error(call->debug_id, ret, afs_io_error_fs_probe_fail);
 		goto out;
 	case -ECONNRESET: /* Responded, but call expired. */
 	case -ERFKILL:
@@ -71,12 +139,11 @@ void afs_fileserver_probe_result(struct afs_call *call)
 		     server->probe.error == -ETIMEDOUT ||
 		     server->probe.error == -ETIME))
 			server->probe.error = ret;
-		afs_io_error(call, afs_io_error_fs_probe_fail);
+		trace_afs_io_error(call->debug_id, ret, afs_io_error_fs_probe_fail);
 		goto out;
 	}
 
 responded:
-	set_bit(index, &alist->responded);
 	clear_bit(index, &alist->failed);
 
 	if (call->service_id == YFS_FS_SERVICE) {
@@ -95,38 +162,31 @@ responded:
 	if (rtt_us < server->probe.rtt) {
 		server->probe.rtt = rtt_us;
 		alist->preferred = index;
-		have_result = true;
 	}
 
 	smp_wmb(); /* Set rtt before responded. */
 	server->probe.responded = true;
-	set_bit(AFS_SERVER_FL_PROBED, &server->flags);
+	set_bit(index, &alist->responded);
 out:
 	spin_unlock(&server->probe_lock);
 
-	_debug("probe [%u][%u] %pISpc rtt=%u ret=%d",
-	       server_index, index, &alist->addrs[index].transport, rtt_us, ret);
+	_debug("probe %pU [%u] %pISpc rtt=%u ret=%d",
+	       &server->uuid, index, &alist->addrs[index].transport,
+	       rtt_us, ret);
 
-	have_result |= afs_fs_probe_done(server);
-	if (have_result)
-		wake_up_all(&server->probe_wq);
+	return afs_done_one_fs_probe(call->net, server);
 }
 
 /*
- * Probe all of a fileserver's addresses to find out the best route and to
- * query its capabilities.
+ * Probe one or all of a fileserver's addresses to find out the best route and
+ * to query its capabilities.
  */
-static int afs_do_probe_fileserver(struct afs_net *net,
-				   struct afs_server *server,
-				   struct key *key,
-				   unsigned int server_index,
-				   struct afs_error *_e)
+void afs_fs_probe_fileserver(struct afs_net *net, struct afs_server *server,
+			     struct key *key, bool all)
 {
 	struct afs_addr_cursor ac = {
 		.index = 0,
 	};
-	struct afs_call *call;
-	bool in_progress = false;
 
 	_enter("%pU", &server->uuid);
 
@@ -136,50 +196,25 @@ static int afs_do_probe_fileserver(struct afs_net *net,
 	afs_get_addrlist(ac.alist);
 	read_unlock(&server->fs_lock);
 
-	atomic_set(&server->probe_outstanding, ac.alist->nr_addrs);
+	server->probed_at = jiffies;
+	atomic_set(&server->probe_outstanding, all ? ac.alist->nr_addrs : 1);
 	memset(&server->probe, 0, sizeof(server->probe));
 	server->probe.rtt = UINT_MAX;
 
-	for (ac.index = 0; ac.index < ac.alist->nr_addrs; ac.index++) {
-		call = afs_fs_get_capabilities(net, server, &ac, key, server_index);
-		if (!IS_ERR(call)) {
-			afs_put_call(call);
-			in_progress = true;
-		} else {
-			afs_prioritise_error(_e, PTR_ERR(call), ac.abort_code);
-		}
-	}
-
-	if (!in_progress)
-		afs_fs_probe_done(server);
-	afs_put_addrlist(ac.alist);
-	return in_progress;
-}
+	ac.index = ac.alist->preferred;
+	if (ac.index < 0 || ac.index >= ac.alist->nr_addrs)
+		all = true;
 
-/*
- * Send off probes to all unprobed servers.
- */
-int afs_probe_fileservers(struct afs_net *net, struct key *key,
-			  struct afs_server_list *list)
-{
-	struct afs_server *server;
-	struct afs_error e;
-	bool in_progress = false;
-	int i;
-
-	e.error = 0;
-	e.responded = false;
-	for (i = 0; i < list->nr_servers; i++) {
-		server = list->servers[i].server;
-		if (test_bit(AFS_SERVER_FL_PROBED, &server->flags))
-			continue;
-
-		if (!test_and_set_bit_lock(AFS_SERVER_FL_PROBING, &server->flags) &&
-		    afs_do_probe_fileserver(net, server, key, i, &e))
-			in_progress = true;
+	if (all) {
+		for (ac.index = 0; ac.index < ac.alist->nr_addrs; ac.index++)
+			if (!afs_fs_get_capabilities(net, server, &ac, key))
+				afs_fs_probe_not_done(net, server, &ac);
+	} else {
+		if (!afs_fs_get_capabilities(net, server, &ac, key))
+			afs_fs_probe_not_done(net, server, &ac);
 	}
 
-	return in_progress ? 0 : e.error;
+	afs_put_addrlist(ac.alist);
 }
 
 /*
@@ -199,7 +234,7 @@ int afs_wait_for_fs_probes(struct afs_server_list *slist, unsigned long untried)
 	for (i = 0; i < slist->nr_servers; i++) {
 		if (test_bit(i, &untried)) {
 			server = slist->servers[i].server;
-			if (!test_bit(AFS_SERVER_FL_PROBING, &server->flags))
+			if (!atomic_read(&server->probe_outstanding))
 				__clear_bit(i, &untried);
 			if (server->probe.responded)
 				have_responders = true;
@@ -229,7 +264,7 @@ int afs_wait_for_fs_probes(struct afs_server_list *slist, unsigned long untried)
 				server = slist->servers[i].server;
 				if (server->probe.responded)
 					goto stop;
-				if (test_bit(AFS_SERVER_FL_PROBING, &server->flags))
+				if (atomic_read(&server->probe_outstanding))
 					still_probing = true;
 			}
 		}
@@ -264,3 +299,109 @@ stop:
 		slist->preferred = pref;
 	return 0;
 }
+
+/*
+ * Probe timer.  We have an increment on fs_outstanding that we need to pass
+ * along to the work item.
+ */
+void afs_fs_probe_timer(struct timer_list *timer)
+{
+	struct afs_net *net = container_of(timer, struct afs_net, fs_probe_timer);
+
+	if (!queue_work(afs_wq, &net->fs_prober))
+		afs_dec_servers_outstanding(net);
+}
+
+/*
+ * Dispatch a probe to a server.
+ */
+static void afs_dispatch_fs_probe(struct afs_net *net, struct afs_server *server, bool all)
+	__releases(&net->fs_lock)
+{
+	struct key *key = NULL;
+
+	/* We remove it from the queues here - it will be added back to
+	 * one of the queues on the completion of the probe.
+	 */
+	list_del_init(&server->probe_link);
+
+	afs_get_server(server, afs_server_trace_get_probe);
+	write_sequnlock(&net->fs_lock);
+
+	afs_fs_probe_fileserver(net, server, key, all);
+	afs_put_server(net, server, afs_server_trace_put_probe);
+}
+
+/*
+ * Probe dispatcher to regularly dispatch probes to keep NAT alive.
+ */
+void afs_fs_probe_dispatcher(struct work_struct *work)
+{
+	struct afs_net *net = container_of(work, struct afs_net, fs_prober);
+	struct afs_server *fast, *slow, *server;
+	unsigned long nowj, timer_at, poll_at;
+	bool first_pass = true, set_timer = false;
+
+	if (!net->live)
+		return;
+
+	_enter("");
+
+	if (list_empty(&net->fs_probe_fast) && list_empty(&net->fs_probe_slow)) {
+		_leave(" [none]");
+		return;
+	}
+
+again:
+	write_seqlock(&net->fs_lock);
+
+	fast = slow = server = NULL;
+	nowj = jiffies;
+	timer_at = nowj + MAX_JIFFY_OFFSET;
+
+	if (!list_empty(&net->fs_probe_fast)) {
+		fast = list_first_entry(&net->fs_probe_fast, struct afs_server, probe_link);
+		poll_at = fast->probed_at + afs_fs_probe_fast_poll_interval;
+		if (time_before(nowj, poll_at)) {
+			timer_at = poll_at;
+			set_timer = true;
+			fast = NULL;
+		}
+	}
+
+	if (!list_empty(&net->fs_probe_slow)) {
+		slow = list_first_entry(&net->fs_probe_slow, struct afs_server, probe_link);
+		poll_at = slow->probed_at + afs_fs_probe_slow_poll_interval;
+		if (time_before(nowj, poll_at)) {
+			if (time_before(poll_at, timer_at))
+			    timer_at = poll_at;
+			set_timer = true;
+			slow = NULL;
+		}
+	}
+
+	server = fast ?: slow;
+	if (server)
+		_debug("probe %pU", &server->uuid);
+
+	if (server && (first_pass || !need_resched())) {
+		afs_dispatch_fs_probe(net, server, server == fast);
+		first_pass = false;
+		goto again;
+	}
+
+	write_sequnlock(&net->fs_lock);
+
+	if (server) {
+		if (!queue_work(afs_wq, &net->fs_prober))
+			afs_dec_servers_outstanding(net);
+		_leave(" [requeue]");
+	} else if (set_timer) {
+		if (timer_reduce(&net->fs_probe_timer, timer_at))
+			afs_dec_servers_outstanding(net);
+		_leave(" [timer]");
+	} else {
+		afs_dec_servers_outstanding(net);
+		_leave(" [quiesce]");
+	}
+}
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 3854d16e14b1..401de063996c 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -1905,14 +1905,13 @@ static const struct afs_call_type afs_RXFSGetCapabilities = {
 };
 
 /*
- * Probe a fileserver for the capabilities that it supports.  This can
- * return up to 196 words.
- */
-struct afs_call *afs_fs_get_capabilities(struct afs_net *net,
-					 struct afs_server *server,
-					 struct afs_addr_cursor *ac,
-					 struct key *key,
-					 unsigned int server_index)
+ * Probe a fileserver for the capabilities that it supports.  This RPC can
+ * reply with up to 196 words.  The operation is asynchronous and if we managed
+ * to allocate a call, true is returned the result is delivered through the
+ * ->done() - otherwise we return false to indicate we didn't even try.
+ */
+bool afs_fs_get_capabilities(struct afs_net *net, struct afs_server *server,
+			     struct afs_addr_cursor *ac, struct key *key)
 {
 	struct afs_call *call;
 	__be32 *bp;
@@ -1921,11 +1920,10 @@ struct afs_call *afs_fs_get_capabilities(struct afs_net *net,
 
 	call = afs_alloc_flat_call(net, &afs_RXFSGetCapabilities, 1 * 4, 16 * 4);
 	if (!call)
-		return ERR_PTR(-ENOMEM);
+		return false;
 
 	call->key = key;
 	call->server = afs_use_server(server, afs_server_trace_get_caps);
-	call->server_index = server_index;
 	call->upgrade = true;
 	call->async = true;
 	call->max_lifespan = AFS_PROBE_MAX_LIFESPAN;
@@ -1936,7 +1934,8 @@ struct afs_call *afs_fs_get_capabilities(struct afs_net *net,
 
 	trace_afs_make_fs_call(call, NULL);
 	afs_make_call(ac, call, GFP_NOFS);
-	return call;
+	afs_put_call(call);
+	return true;
 }
 
 /*
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index cb70e1c234cc..61320a632e15 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -90,7 +90,6 @@ struct afs_addr_list {
 	unsigned char		nr_ipv4;	/* Number of IPv4 addresses */
 	enum dns_record_source	source:8;
 	enum dns_lookup_status	status:8;
-	unsigned long		probed;		/* Mask of servers that have been probed */
 	unsigned long		failed;		/* Mask of addrs that failed locally/ICMP */
 	unsigned long		responded;	/* Mask of addrs that responded */
 	struct sockaddr_rxrpc	addrs[];
@@ -299,9 +298,10 @@ struct afs_net {
 	 * cell, but in practice, people create aliases and subsets and there's
 	 * no easy way to distinguish them.
 	 */
-	seqlock_t		fs_lock;	/* For fs_servers */
+	seqlock_t		fs_lock;	/* For fs_servers, fs_probe_*, fs_proc */
 	struct rb_root		fs_servers;	/* afs_server (by server UUID or address) */
-	struct list_head	fs_updates;	/* afs_server (by update_at) */
+	struct list_head	fs_probe_fast;	/* List of afs_server to probe at 30s intervals */
+	struct list_head	fs_probe_slow;	/* List of afs_server to probe at 5m intervals */
 	struct hlist_head	fs_proc;	/* procfs servers list */
 
 	struct hlist_head	fs_addresses4;	/* afs_server (by lowest IPv4 addr) */
@@ -310,6 +310,9 @@ struct afs_net {
 
 	struct work_struct	fs_manager;
 	struct timer_list	fs_timer;
+
+	struct work_struct	fs_prober;
+	struct timer_list	fs_probe_timer;
 	atomic_t		servers_outstanding;
 
 	/* File locking renewal management */
@@ -493,7 +496,8 @@ struct afs_server {
 	};
 
 	struct afs_addr_list	__rcu *addresses;
-	struct rb_node		uuid_rb;	/* Link in net->servers */
+	struct rb_node		uuid_rb;	/* Link in net->fs_servers */
+	struct list_head	probe_link;	/* Link in net->fs_probe_list */
 	struct hlist_node	addr4_link;	/* Link in net->fs_addresses4 */
 	struct hlist_node	addr6_link;	/* Link in net->fs_addresses6 */
 	struct hlist_node	proc_link;	/* Link in net->fs_proc */
@@ -504,8 +508,6 @@ struct afs_server {
 #define AFS_SERVER_FL_NOT_FOUND	2		/* VL server says no such server */
 #define AFS_SERVER_FL_VL_FAIL	3		/* Failed to access VL server */
 #define AFS_SERVER_FL_UPDATING	4
-#define AFS_SERVER_FL_PROBED	5		/* The fileserver has been probed */
-#define AFS_SERVER_FL_PROBING	6		/* Fileserver is being probed */
 #define AFS_SERVER_FL_NO_IBULK	7		/* Fileserver doesn't support FS.InlineBulkStatus */
 #define AFS_SERVER_FL_MAY_HAVE_CB 8		/* May have callbacks on this fileserver */
 #define AFS_SERVER_FL_IS_YFS	9		/* Server is YFS not AFS */
@@ -527,6 +529,7 @@ struct afs_server {
 	rwlock_t		cb_break_lock;	/* Volume finding lock */
 
 	/* Probe state */
+	unsigned long		probed_at;	/* Time last probe was dispatched (jiffies) */
 	wait_queue_head_t	probe_wq;
 	atomic_t		probe_outstanding;
 	spinlock_t		probe_lock;
@@ -956,7 +959,6 @@ extern int afs_flock(struct file *, int, struct file_lock *);
  */
 extern int afs_fs_fetch_file_status(struct afs_fs_cursor *, struct afs_status_cb *,
 				    struct afs_volsync *);
-extern int afs_fs_give_up_callbacks(struct afs_net *, struct afs_server *);
 extern int afs_fs_fetch_data(struct afs_fs_cursor *, struct afs_status_cb *, struct afs_read *);
 extern int afs_fs_create(struct afs_fs_cursor *, const char *, umode_t,
 			 struct afs_status_cb *, struct afs_fid *, struct afs_status_cb *);
@@ -978,9 +980,8 @@ extern int afs_fs_extend_lock(struct afs_fs_cursor *, struct afs_status_cb *);
 extern int afs_fs_release_lock(struct afs_fs_cursor *, struct afs_status_cb *);
 extern int afs_fs_give_up_all_callbacks(struct afs_net *, struct afs_server *,
 					struct afs_addr_cursor *, struct key *);
-extern struct afs_call *afs_fs_get_capabilities(struct afs_net *, struct afs_server *,
-						struct afs_addr_cursor *, struct key *,
-						unsigned int);
+extern bool afs_fs_get_capabilities(struct afs_net *, struct afs_server *,
+				    struct afs_addr_cursor *, struct key *);
 extern int afs_fs_inline_bulk_status(struct afs_fs_cursor *, struct afs_net *,
 				     struct afs_fid *, struct afs_status_cb *,
 				     unsigned int, struct afs_volsync *);
@@ -1001,8 +1002,9 @@ extern int afs_fs_store_acl(struct afs_fs_cursor *, const struct afs_acl *,
  * fs_probe.c
  */
 extern void afs_fileserver_probe_result(struct afs_call *);
-extern int afs_probe_fileservers(struct afs_net *, struct key *, struct afs_server_list *);
+extern void afs_fs_probe_fileserver(struct afs_net *, struct afs_server *, struct key *, bool);
 extern int afs_wait_for_fs_probes(struct afs_server_list *, unsigned long);
+extern void afs_fs_probe_dispatcher(struct work_struct *);
 
 /*
  * inode.c
@@ -1251,9 +1253,26 @@ extern void afs_unuse_server_notime(struct afs_net *, struct afs_server *, enum
 extern void afs_put_server(struct afs_net *, struct afs_server *, enum afs_server_trace);
 extern void afs_manage_servers(struct work_struct *);
 extern void afs_servers_timer(struct timer_list *);
+extern void afs_fs_probe_timer(struct timer_list *);
 extern void __net_exit afs_purge_servers(struct afs_net *);
 extern bool afs_check_server_record(struct afs_fs_cursor *, struct afs_server *);
 
+static inline void afs_inc_servers_outstanding(struct afs_net *net)
+{
+	atomic_inc(&net->servers_outstanding);
+}
+
+static inline void afs_dec_servers_outstanding(struct afs_net *net)
+{
+	if (atomic_dec_and_test(&net->servers_outstanding))
+		wake_up_var(&net->servers_outstanding);
+}
+
+static inline bool afs_is_probing_server(struct afs_server *server)
+{
+	return list_empty(&server->probe_link);
+}
+
 /*
  * server_list.c
  */
diff --git a/fs/afs/main.c b/fs/afs/main.c
index c9c45d7078bd..56b52f8dbf15 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -87,7 +87,8 @@ static int __net_init afs_net_init(struct net *net_ns)
 
 	seqlock_init(&net->fs_lock);
 	net->fs_servers = RB_ROOT;
-	INIT_LIST_HEAD(&net->fs_updates);
+	INIT_LIST_HEAD(&net->fs_probe_fast);
+	INIT_LIST_HEAD(&net->fs_probe_slow);
 	INIT_HLIST_HEAD(&net->fs_proc);
 
 	INIT_HLIST_HEAD(&net->fs_addresses4);
@@ -96,6 +97,8 @@ static int __net_init afs_net_init(struct net *net_ns)
 
 	INIT_WORK(&net->fs_manager, afs_manage_servers);
 	timer_setup(&net->fs_timer, afs_servers_timer, 0);
+	INIT_WORK(&net->fs_prober, afs_fs_probe_dispatcher);
+	timer_setup(&net->fs_probe_timer, afs_fs_probe_timer, 0);
 
 	ret = -ENOMEM;
 	sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c
index 2a3305e42b14..46b68da89faa 100644
--- a/fs/afs/rotate.c
+++ b/fs/afs/rotate.c
@@ -349,9 +349,6 @@ start:
 		goto failed;
 
 	_debug("__ VOL %llx __", vnode->volume->vid);
-	error = afs_probe_fileservers(afs_v2net(vnode), fc->key, fc->server_list);
-	if (error < 0)
-		goto failed_set_error;
 
 pick_server:
 	_debug("pick [%lx]", fc->untried);
@@ -596,8 +593,8 @@ static void afs_dump_edestaddrreq(const struct afs_fs_cursor *fc)
 					  a->version,
 					  a->nr_ipv4, a->nr_addrs, a->max_addrs,
 					  a->preferred);
-				pr_notice("FC:  - pr=%lx R=%lx F=%lx\n",
-					  a->probed, a->responded, a->failed);
+				pr_notice("FC:  - R=%lx F=%lx\n",
+					  a->responded, a->failed);
 				if (a == fc->ac.alist)
 					pr_notice("FC:  - current\n");
 			}
diff --git a/fs/afs/server.c b/fs/afs/server.c
index 4969a681f8f5..3f707b5ecb62 100644
--- a/fs/afs/server.c
+++ b/fs/afs/server.c
@@ -14,17 +14,6 @@
 static unsigned afs_server_gc_delay = 10;	/* Server record timeout in seconds */
 static atomic_t afs_server_debug_id;
 
-static void afs_inc_servers_outstanding(struct afs_net *net)
-{
-	atomic_inc(&net->servers_outstanding);
-}
-
-static void afs_dec_servers_outstanding(struct afs_net *net)
-{
-	if (atomic_dec_and_test(&net->servers_outstanding))
-		wake_up_var(&net->servers_outstanding);
-}
-
 static struct afs_server *afs_maybe_use_server(struct afs_server *,
 					       enum afs_server_trace);
 static void __afs_put_server(struct afs_net *, struct afs_server *);
@@ -226,6 +215,7 @@ static struct afs_server *afs_alloc_server(struct afs_net *net,
 	INIT_HLIST_HEAD(&server->cb_volumes);
 	rwlock_init(&server->cb_break_lock);
 	init_waitqueue_head(&server->probe_wq);
+	INIT_LIST_HEAD(&server->probe_link);
 	spin_lock_init(&server->probe_lock);
 
 	afs_inc_servers_outstanding(net);
@@ -295,6 +285,12 @@ struct afs_server *afs_lookup_server(struct afs_cell *cell, struct key *key,
 	if (server != candidate) {
 		afs_put_addrlist(alist);
 		kfree(candidate);
+	} else {
+		/* Immediately dispatch an asynchronous probe to each interface
+		 * on the fileserver.  This will make sure the repeat-probing
+		 * service is started.
+		 */
+		afs_fs_probe_fileserver(cell->net, server, key, true);
 	}
 
 	return server;
@@ -464,6 +460,7 @@ static void afs_gc_servers(struct afs_net *net, struct afs_server *gc_list)
 			trace_afs_server(server, atomic_read(&server->ref),
 					 active, afs_server_trace_gc);
 			rb_erase(&server->uuid_rb, &net->fs_servers);
+			list_del(&server->probe_link);
 			hlist_del_rcu(&server->proc_link);
 			if (!hlist_unhashed(&server->addr4_link))
 				hlist_del_rcu(&server->addr4_link);
diff --git a/fs/afs/volume.c b/fs/afs/volume.c
index 4310336b9bb8..249000195f8a 100644
--- a/fs/afs/volume.c
+++ b/fs/afs/volume.c
@@ -266,7 +266,6 @@ static int afs_update_volume_status(struct afs_volume *volume, struct key *key)
 	}
 
 	volume->update_at = ktime_get_real_seconds() + afs_volume_record_life;
-	clear_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
 	write_unlock(&volume->servers_lock);
 	ret = 0;
 
@@ -283,23 +282,25 @@ error:
  */
 int afs_check_volume_status(struct afs_volume *volume, struct afs_fs_cursor *fc)
 {
-	time64_t now = ktime_get_real_seconds();
 	int ret, retries = 0;
 
 	_enter("");
 
-	if (volume->update_at <= now)
-		set_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
-
 retry:
-	if (!test_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags) &&
-	    !test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
-		_leave(" = 0");
-		return 0;
-	}
-
+	if (test_bit(AFS_VOLUME_WAIT, &volume->flags))
+		goto wait;
+	if (volume->update_at <= ktime_get_real_seconds() ||
+	    test_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags))
+		goto update;
+	_leave(" = 0");
+	return 0;
+
+update:
 	if (!test_and_set_bit_lock(AFS_VOLUME_UPDATING, &volume->flags)) {
+		clear_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
 		ret = afs_update_volume_status(volume, fc->key);
+		if (ret < 0)
+			set_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
 		clear_bit_unlock(AFS_VOLUME_WAIT, &volume->flags);
 		clear_bit_unlock(AFS_VOLUME_UPDATING, &volume->flags);
 		wake_up_bit(&volume->flags, AFS_VOLUME_WAIT);
@@ -307,6 +308,7 @@ retry:
 		return ret;
 	}
 
+wait:
 	if (!test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
 		_leave(" = 0 [no wait]");
 		return 0;
diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h
index f9691f69b2d6..19a07fbf35df 100644
--- a/include/trace/events/afs.h
+++ b/include/trace/events/afs.h
@@ -38,10 +38,12 @@ enum afs_server_trace {
 	afs_server_trace_get_caps,
 	afs_server_trace_get_install,
 	afs_server_trace_get_new_cbi,
+	afs_server_trace_get_probe,
 	afs_server_trace_give_up_cb,
 	afs_server_trace_put_call,
 	afs_server_trace_put_cbi,
 	afs_server_trace_put_find_rsq,
+	afs_server_trace_put_probe,
 	afs_server_trace_put_slist,
 	afs_server_trace_put_slist_isort,
 	afs_server_trace_put_uuid_rsq,
@@ -247,10 +249,12 @@ enum afs_cb_break_reason {
 	EM(afs_server_trace_get_caps,		"GET caps ") \
 	EM(afs_server_trace_get_install,	"GET inst ") \
 	EM(afs_server_trace_get_new_cbi,	"GET cbi  ") \
+	EM(afs_server_trace_get_probe,		"GET probe") \
 	EM(afs_server_trace_give_up_cb,		"giveup-cb") \
 	EM(afs_server_trace_put_call,		"PUT call ") \
 	EM(afs_server_trace_put_cbi,		"PUT cbi  ") \
 	EM(afs_server_trace_put_find_rsq,	"PUT f-rsq") \
+	EM(afs_server_trace_put_probe,		"PUT probe") \
 	EM(afs_server_trace_put_slist,		"PUT slist") \
 	EM(afs_server_trace_put_slist_isort,	"PUT isort") \
 	EM(afs_server_trace_put_uuid_rsq,	"PUT u-req") \