diff options
| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2008-12-23 15:21:38 -0500 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2008-12-23 15:21:38 -0500 |
| commit | 343104308a33c4f1e23c8e841ede95e97b870842 (patch) | |
| tree | e7772538627a0a2176bd23cd3b2f1acbacd24592 /fs/nfs/delegation.c | |
| parent | 0cb2659b818eca99235e17c04291cfa9985c14f7 (diff) | |
NFSv4: Fix up another delegation related race
When we can update_open_stateid(), we need to be certain that we don't
race with a delegation return. While we could do this by grabbing the
nfs_client->cl_lock, a dedicated spin lock in the delegation structure
will scale better.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/delegation.c')
| -rw-r--r-- | fs/nfs/delegation.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index cc563cfa6940..e0cb4ee3b23e 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -140,13 +140,17 @@ static struct nfs_delegation *nfs_detach_delegation_locked(struct nfs_inode *nfs if (delegation == NULL) goto nomatch; + spin_lock(&delegation->lock); if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data, sizeof(delegation->stateid.data)) != 0) - goto nomatch; + goto nomatch_unlock; list_del_rcu(&delegation->super_list); nfsi->delegation_state = 0; rcu_assign_pointer(nfsi->delegation, NULL); + spin_unlock(&delegation->lock); return delegation; +nomatch_unlock: + spin_unlock(&delegation->lock); nomatch: return NULL; } @@ -172,6 +176,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct delegation->change_attr = nfsi->change_attr; delegation->cred = get_rpccred(cred); delegation->inode = inode; + spin_lock_init(&delegation->lock); spin_lock(&clp->cl_lock); if (rcu_dereference(nfsi->delegation) != NULL) { |