nfsd: Ensure stateids remain unique until they are freed

Add an extra delegation state to allow the stateid to remain in the idr
tree until the last reference has been released. This will be necessary
to ensure uniqueness once the client_mutex is removed.

[jlayton: reset the sc_type under the state_lock in unhash_delegation]

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 1b01a20827ab..fd4deb049ddf 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -616,6 +616,7 @@ void
 nfs4_put_delegation(struct nfs4_delegation *dp)
 {
 	if (atomic_dec_and_test(&dp->dl_count)) {
+		remove_stid(&dp->dl_stid);
 		nfs4_free_stid(deleg_slab, &dp->dl_stid);
 		num_delegations--;
 	}
@@ -657,6 +658,7 @@ unhash_delegation(struct nfs4_delegation *dp)
 	struct nfs4_file *fp = dp->dl_file;
 
 	spin_lock(&state_lock);
+	dp->dl_stid.sc_type = NFS4_CLOSED_DELEG_STID;
 	list_del_init(&dp->dl_perclnt);
 	list_del_init(&dp->dl_recall_lru);
 	spin_lock(&fp->fi_lock);
@@ -670,19 +672,15 @@ unhash_delegation(struct nfs4_delegation *dp)
 	}
 }
 
-
-
 static void destroy_revoked_delegation(struct nfs4_delegation *dp)
 {
 	list_del_init(&dp->dl_recall_lru);
-	remove_stid(&dp->dl_stid);
 	nfs4_put_delegation(dp);
 }
 
 static void destroy_delegation(struct nfs4_delegation *dp)
 {
 	unhash_delegation(dp);
-	remove_stid(&dp->dl_stid);
 	nfs4_put_delegation(dp);
 }
 
@@ -4036,7 +4034,9 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
 		return nfs_ok;
 	default:
 		printk("unknown stateid type %x\n", s->sc_type);
+		/* Fallthrough */
 	case NFS4_CLOSED_STID:
+	case NFS4_CLOSED_DELEG_STID:
 		return nfserr_bad_stateid;
 	}
 }