NFSv4: Ensure we honour NFS_DELEGATION_RETURNING in nfs_inode_set_delegation()
Ensure that nfs_inode_set_delegation() doesn't inadvertently detach a
delegation that is already in the process of being returned.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index d9caf73..5ca502b 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -370,7 +370,10 @@
delegation = NULL;
goto out;
}
- freeme = nfs_detach_delegation_locked(nfsi,
+ if (test_and_set_bit(NFS_DELEGATION_RETURNING,
+ &old_delegation->flags))
+ goto out;
+ freeme = nfs_detach_delegation_locked(nfsi,
old_delegation, clp);
if (freeme == NULL)
goto out;