5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: NeilBrown neilb@suse.de
[ 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@suse.de Signed-off-by: Chuck Lever chuck.lever@oracle.com --- 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;