NFSv4: Ensure that nfs4_reclaim_open_state() doesn't depend on cl_sem

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 7dcca23167dd..beade5570b56 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -893,11 +893,15 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
          * recovering after a network partition or a reboot from a
          * server that doesn't support a grace period.
          */
+restart:
+        spin_lock(&sp->so_lock);
         list_for_each_entry(state, &sp->so_states, open_states) {
                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
                         continue;
                 if (state->state == 0)
                         continue;
+                atomic_inc(&state->count);
+                spin_unlock(&sp->so_lock);
                 status = ops->recover_open(sp, state);
                 if (status >= 0) {
                         status = nfs4_reclaim_locks(state, ops);
@@ -907,7 +911,8 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
                                                 printk("%s: Lock reclaim failed!\n",
                                                         __func__);
                                 }
-                                continue;
+                                nfs4_put_open_state(state);
+                                goto restart;
                         }
                 }
                 switch (status) {
@@ -935,9 +940,13 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
                         case -NFS4ERR_STALE_CLIENTID:
                                 goto out_err;
                 }
+                nfs4_put_open_state(state);
+                goto restart;
         }
+        spin_unlock(&sp->so_lock);
         return 0;
 out_err:
+        nfs4_put_open_state(state);
         return status;
 }