NFS: Properly handle the case where the delegation is revoked

If we know that the delegation stateid is bad or revoked, we need to
remove that delegation as soon as possible, and then mark all the
stateids that relied on that delegation for recovery. We cannot use
the delegation as part of the recovery process.

Also note that NFSv4.1 uses a different error code (NFS4ERR_DELEG_REVOKED)
to indicate that the delegation was revoked.

Finally, ensure that setlk() and setattr() can both recover safely from
a revoked delegation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

1 files changed, 27 insertions, 2 deletions

diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 2f760604246f..d60e7ad2690e 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1106,12 +1106,37 @@ void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4
 {
 	struct nfs_client *clp = server->nfs_client;
 
-	if (test_and_clear_bit(NFS_DELEGATED_STATE, &state->flags))
-		nfs_async_inode_return_delegation(state->inode, &state->stateid);
 	nfs4_state_mark_reclaim_nograce(clp, state);
 	nfs4_schedule_state_manager(clp);
 }
 
+void nfs_inode_find_state_and_recover(struct inode *inode,
+		const nfs4_stateid *stateid)
+{
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+	struct nfs_inode *nfsi = NFS_I(inode);
+	struct nfs_open_context *ctx;
+	struct nfs4_state *state;
+	bool found = false;
+
+	spin_lock(&inode->i_lock);
+	list_for_each_entry(ctx, &nfsi->open_files, list) {
+		state = ctx->state;
+		if (state == NULL)
+			continue;
+		if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
+			continue;
+		if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0)
+			continue;
+		nfs4_state_mark_reclaim_nograce(clp, state);
+		found = true;
+	}
+	spin_unlock(&inode->i_lock);
+	if (found)
+		nfs4_schedule_state_manager(clp);
+}
+
+
 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 {
 	struct inode *inode = state->inode;