2 files changed, 12 insertions, 1 deletions

diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index a3f488b074a2..b12b73472020 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -13,6 +13,8 @@
 
 #define NFS4_MAX_LOOP_ON_RECOVER (10)
 
+#include <linux/seqlock.h>
+
 struct idmap;
 
 enum nfs4_client_state {
@@ -90,6 +92,7 @@ struct nfs4_state_owner {
         unsigned long        so_flags;
         struct list_head     so_states;
         struct nfs_seqid_counter so_seqid;
+        seqcount_t           so_reclaim_seqcount;
 };
 
 enum {
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index e61f68d5ef21..fff97228cdec 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -518,6 +518,7 @@ nfs4_alloc_state_owner(struct nfs_server *server,
         nfs4_init_seqid_counter(&sp->so_seqid);
         atomic_set(&sp->so_count, 1);
         INIT_LIST_HEAD(&sp->so_lru);
+        seqcount_init(&sp->so_reclaim_seqcount);
         return sp;
 }
 
@@ -1390,8 +1391,9 @@ 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);
+        write_seqcount_begin(&sp->so_reclaim_seqcount);
+restart:
         list_for_each_entry(state, &sp->so_states, open_states) {
                 if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
                         continue;
@@ -1412,6 +1414,7 @@ restart:
                                 }
                                 spin_unlock(&state->state_lock);
                                 nfs4_put_open_state(state);
+                                spin_lock(&sp->so_lock);
                                 goto restart;
                         }
                 }
@@ -1449,12 +1452,17 @@ restart:
                                 goto out_err;
                 }
                 nfs4_put_open_state(state);
+                spin_lock(&sp->so_lock);
                 goto restart;
         }
+        write_seqcount_end(&sp->so_reclaim_seqcount);
         spin_unlock(&sp->so_lock);
         return 0;
 out_err:
         nfs4_put_open_state(state);
+        spin_lock(&sp->so_lock);
+        write_seqcount_end(&sp->so_reclaim_seqcount);
+        spin_unlock(&sp->so_lock);
         return status;
 }