NFSv4: Use correct locking when updating nfs4_state in nfs4_close_done

The stateid and state->flags should be updated atomically under
protection of the state->seqlock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 96e0bd4..1f593a0 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1149,6 +1149,38 @@ static bool nfs_need_update_open_stateid(struct nfs4_state *state,
        return false;
 }
 
+static void nfs_clear_open_stateid_locked(struct nfs4_state *state,
+               nfs4_stateid *stateid, fmode_t fmode)
+{
+       clear_bit(NFS_O_RDWR_STATE, &state->flags);
+       switch (fmode & (FMODE_READ|FMODE_WRITE)) {
+       case FMODE_WRITE:
+               clear_bit(NFS_O_RDONLY_STATE, &state->flags);
+               break;
+       case FMODE_READ:
+               clear_bit(NFS_O_WRONLY_STATE, &state->flags);
+               break;
+       case 0:
+               clear_bit(NFS_O_RDONLY_STATE, &state->flags);
+               clear_bit(NFS_O_WRONLY_STATE, &state->flags);
+               clear_bit(NFS_OPEN_STATE, &state->flags);
+       }
+       if (stateid == NULL)
+               return;
+       if (!nfs_need_update_open_stateid(state, stateid))
+               return;
+       if (test_bit(NFS_DELEGATED_STATE, &state->flags) == 0)
+               nfs4_stateid_copy(&state->stateid, stateid);
+       nfs4_stateid_copy(&state->open_stateid, stateid);
+}
+
+static void nfs_clear_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)
+{
+       write_seqlock(&state->seqlock);
+       nfs_clear_open_stateid_locked(state, stateid, fmode);
+       write_sequnlock(&state->seqlock);
+}
+
 static void nfs_set_open_stateid_locked(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)
 {
        switch (fmode) {
@@ -1168,13 +1200,6 @@ static void nfs_set_open_stateid_locked(struct nfs4_state *state, nfs4_stateid *
        nfs4_stateid_copy(&state->open_stateid, stateid);
 }
 
-static void nfs_set_open_stateid(struct nfs4_state *state, nfs4_stateid *stateid, fmode_t fmode)
-{
-       write_seqlock(&state->seqlock);
-       nfs_set_open_stateid_locked(state, stateid, fmode);
-       write_sequnlock(&state->seqlock);
-}
-
 static void __update_open_stateid(struct nfs4_state *state, nfs4_stateid *open_stateid, const nfs4_stateid *deleg_stateid, fmode_t fmode)
 {
        /*
@@ -2489,26 +2514,6 @@ static void nfs4_free_closedata(void *data)
        kfree(calldata);
 }
 
-static void nfs4_close_clear_stateid_flags(struct nfs4_state *state,
-               fmode_t fmode)
-{
-       spin_lock(&state->owner->so_lock);
-       clear_bit(NFS_O_RDWR_STATE, &state->flags);
-       switch (fmode & (FMODE_READ|FMODE_WRITE)) {
-       case FMODE_WRITE:
-               clear_bit(NFS_O_RDONLY_STATE, &state->flags);
-               break;
-       case FMODE_READ:
-               clear_bit(NFS_O_WRONLY_STATE, &state->flags);
-               break;
-       case 0:
-               clear_bit(NFS_O_RDONLY_STATE, &state->flags);
-               clear_bit(NFS_O_WRONLY_STATE, &state->flags);
-               clear_bit(NFS_OPEN_STATE, &state->flags);
-       }
-       spin_unlock(&state->owner->so_lock);
-}
-
 static void nfs4_close_done(struct rpc_task *task, void *data)
 {
        struct nfs4_closedata *calldata = data;
@@ -2527,9 +2532,9 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
                        if (calldata->roc)
                                pnfs_roc_set_barrier(state->inode,
                                                     calldata->roc_barrier);
-                       nfs_set_open_stateid(state, &calldata->res.stateid, 0);
+                       nfs_clear_open_stateid(state, &calldata->res.stateid, 0);
                        renew_lease(server, calldata->timestamp);
-                       break;
+                       goto out_release;
                case -NFS4ERR_ADMIN_REVOKED:
                case -NFS4ERR_STALE_STATEID:
                case -NFS4ERR_OLD_STATEID:
@@ -2543,7 +2548,7 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
                                goto out_release;
                        }
        }
-       nfs4_close_clear_stateid_flags(state, calldata->arg.fmode);
+       nfs_clear_open_stateid(state, NULL, calldata->arg.fmode);
 out_release:
        nfs_release_seqid(calldata->arg.seqid);
        nfs_refresh_inode(calldata->inode, calldata->res.fattr);