2017-11-08 22:30:32

by Andrew W Elble

Subject: [PATCH v3] nfsd: fix locking validator warning on nfs4_ol_stateid->st_mutex class

The use of the st_mutex has been confusing the validator. Use the
proper nested notation so as to not produce warnings.

Signed-off-by: Andrew Elble <[email protected]>
---
v2: added mutex_lock_nested to init_lock_stateid() for consistency
v3: add constants

fs/nfsd/nfs4state.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 0d98d73bd84e..5740ad8075c3 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -87,6 +87,11 @@
*/
static DEFINE_SPINLOCK(state_lock);

+enum nfsd4_st_mutex_lock_subclass {
+ OPEN_STATEID_MUTEX = 0,
+ LOCK_STATEID_MUTEX = 1,
+};
+
/*
* A waitqueue for all in-progress 4.0 CLOSE operations that are waiting for
* the refcount on the open stateid to drop.
@@ -3548,7 +3553,7 @@ static void nfs4_free_openowner(struct nfs4_stateowner *so)
{
__be32 ret;

- mutex_lock(&stp->st_mutex);
+ mutex_lock_nested(&stp->st_mutex, LOCK_STATEID_MUTEX);
ret = nfsd4_verify_open_stid(&stp->st_stid);
if (ret != nfs_ok)
mutex_unlock(&stp->st_mutex);
@@ -3612,7 +3617,7 @@ static void nfs4_free_openowner(struct nfs4_stateowner *so)
stp = open->op_stp;
/* We are moving these outside of the spinlocks to avoid the warnings */
mutex_init(&stp->st_mutex);
- mutex_lock(&stp->st_mutex);
+ mutex_lock_nested(&stp->st_mutex, OPEN_STATEID_MUTEX);

retry:
spin_lock(&oo->oo_owner.so_client->cl_lock);
@@ -5692,7 +5697,7 @@ static void nfs4_free_lockowner(struct nfs4_stateowner *sop)
struct nfs4_ol_stateid *retstp;

mutex_init(&stp->st_mutex);
- mutex_lock(&stp->st_mutex);
+ mutex_lock_nested(&stp->st_mutex, OPEN_STATEID_MUTEX);
retry:
spin_lock(&clp->cl_lock);
spin_lock(&fp->fi_lock);
--
1.8.3.1

2017-11-09 02:30:37

by J. Bruce Fields

Subject: Re: [PATCH v3] nfsd: fix locking validator warning on nfs4_ol_stateid->st_mutex class

Thanks! Applied.--b.

On Wed, Nov 08, 2017 at 05:29:51PM -0500, Andrew Elble wrote:
> The use of the st_mutex has been confusing the validator. Use the
> proper nested notation so as to not produce warnings.
>
> Signed-off-by: Andrew Elble <[email protected]>
> ---
> v2: added mutex_lock_nested to init_lock_stateid() for consistency
> v3: add constants
>
> fs/nfsd/nfs4state.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 0d98d73bd84e..5740ad8075c3 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -87,6 +87,11 @@
> */
> static DEFINE_SPINLOCK(state_lock);
>
> +enum nfsd4_st_mutex_lock_subclass {
> + OPEN_STATEID_MUTEX = 0,
> + LOCK_STATEID_MUTEX = 1,
> +};
> +
> /*
> * A waitqueue for all in-progress 4.0 CLOSE operations that are waiting for
> * the refcount on the open stateid to drop.
> @@ -3548,7 +3553,7 @@ static void nfs4_free_openowner(struct nfs4_stateowner *so)
> {
> __be32 ret;
>
> - mutex_lock(&stp->st_mutex);
> + mutex_lock_nested(&stp->st_mutex, LOCK_STATEID_MUTEX);
> ret = nfsd4_verify_open_stid(&stp->st_stid);
> if (ret != nfs_ok)
> mutex_unlock(&stp->st_mutex);
> @@ -3612,7 +3617,7 @@ static void nfs4_free_openowner(struct nfs4_stateowner *so)
> stp = open->op_stp;
> /* We are moving these outside of the spinlocks to avoid the warnings */
> mutex_init(&stp->st_mutex);
> - mutex_lock(&stp->st_mutex);
> + mutex_lock_nested(&stp->st_mutex, OPEN_STATEID_MUTEX);
>
> retry:
> spin_lock(&oo->oo_owner.so_client->cl_lock);
> @@ -5692,7 +5697,7 @@ static void nfs4_free_lockowner(struct nfs4_stateowner *sop)
> struct nfs4_ol_stateid *retstp;
>
> mutex_init(&stp->st_mutex);
> - mutex_lock(&stp->st_mutex);
> + mutex_lock_nested(&stp->st_mutex, OPEN_STATEID_MUTEX);
> retry:
> spin_lock(&clp->cl_lock);
> spin_lock(&fp->fi_lock);
> --
> 1.8.3.1