5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: NeilBrown <neilb@xxxxxxx>
[ Upstream commit b73a2972041bee70eb0cbbb25fa77828c63c916b ]
lockd_start_svc() only needs to be called once, just after the svc is
created. If the start fails, the svc is discarded too.
It thus makes sense to call lockd_start_svc() from lockd_create_svc().
This allows us to remove the test against nlmsvc_rqst at the start of
lockd_start_svc() - it must always be NULL.
lockd_up() only held an extra reference on the svc until a thread was
created - then it dropped it. The thread - and thus the extra reference
- will remain until kthread_stop() is called.
Now that the thread is created in lockd_create_svc(), the extra
reference can be dropped there. So the 'serv' variable is no longer
needed in lockd_up().
Signed-off-by: NeilBrown <neilb@xxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/lockd/svc.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 20cebb191350f..91e7c839841ec 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -359,9 +359,6 @@ static int lockd_start_svc(struct svc_serv *serv)
{
int error;
- if (nlmsvc_rqst)
- return 0;
-
/*
* Create the kernel thread and wait for it to start.
*/
@@ -406,6 +403,7 @@ static const struct svc_serv_ops lockd_sv_ops = {
static int lockd_create_svc(void)
{
struct svc_serv *serv;
+ int error;
/*
* Check whether we're already up and running.
@@ -432,6 +430,13 @@ static int lockd_create_svc(void)
printk(KERN_WARNING "lockd_up: create service failed\n");
return -ENOMEM;
}
+
+ error = lockd_start_svc(serv);
+ /* The thread now holds the only reference */
+ svc_put(serv);
+ if (error < 0)
+ return error;
+
nlmsvc_serv = serv;
register_inetaddr_notifier(&lockd_inetaddr_notifier);
#if IS_ENABLED(CONFIG_IPV6)
@@ -446,7 +451,6 @@ static int lockd_create_svc(void)
*/
int lockd_up(struct net *net, const struct cred *cred)
{
- struct svc_serv *serv;
int error;
mutex_lock(&nlmsvc_mutex);
@@ -454,25 +458,19 @@ int lockd_up(struct net *net, const struct cred *cred)
error = lockd_create_svc();
if (error)
goto err_create;
- serv = nlmsvc_serv;
- error = lockd_up_net(serv, net, cred);
+ error = lockd_up_net(nlmsvc_serv, net, cred);
if (error < 0) {
goto err_put;
}
- error = lockd_start_svc(serv);
- if (error < 0) {
- lockd_down_net(serv, net);
- goto err_put;
- }
nlmsvc_users++;
err_put:
if (nlmsvc_users == 0) {
lockd_unregister_notifiers();
+ kthread_stop(nlmsvc_task);
nlmsvc_serv = NULL;
}
- svc_put(serv);
err_create:
mutex_unlock(&nlmsvc_mutex);
return error;
--
2.43.0
