1 files changed, 34 insertions, 11 deletions

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index a1f0685b42ff..a6ad68865880 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -181,8 +181,8 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
                         clear_bit(NFS_DELEGATION_NEED_RECLAIM,
                                   &delegation->flags);
                         spin_unlock(&delegation->lock);
-                        put_rpccred(oldcred);
                         rcu_read_unlock();
+                        put_rpccred(oldcred);
                         trace_nfs4_reclaim_delegation(inode, res->delegation_type);
                 } else {
                         /* We appear to have raced with a delegation return. */
@@ -370,7 +370,10 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
                         delegation = NULL;
                         goto out;
                 }
-                freeme = nfs_detach_delegation_locked(nfsi, 
+                if (test_and_set_bit(NFS_DELEGATION_RETURNING,
+                                        &old_delegation->flags))
+                        goto out;
+                freeme = nfs_detach_delegation_locked(nfsi,
                                 old_delegation, clp);
                 if (freeme == NULL)
                         goto out;
@@ -433,6 +436,8 @@ static bool nfs_delegation_need_return(struct nfs_delegation *delegation)
 {
         bool ret = false;
 
+        if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
+                goto out;
         if (test_and_clear_bit(NFS_DELEGATION_RETURN, &delegation->flags))
                 ret = true;
         if (test_and_clear_bit(NFS_DELEGATION_RETURN_IF_CLOSED, &delegation->flags) && !ret) {
@@ -444,6 +449,7 @@ static bool nfs_delegation_need_return(struct nfs_delegation *delegation)
                         ret = true;
                 spin_unlock(&delegation->lock);
         }
+out:
         return ret;
 }
 
@@ -471,14 +477,20 @@ restart:
                                                                 super_list) {
                         if (!nfs_delegation_need_return(delegation))
                                 continue;
-                        inode = nfs_delegation_grab_inode(delegation);
-                        if (inode == NULL)
+                        if (!nfs_sb_active(server->super))
                                 continue;
+                        inode = nfs_delegation_grab_inode(delegation);
+                        if (inode == NULL) {
+                                rcu_read_unlock();
+                                nfs_sb_deactive(server->super);
+                                goto restart;
+                        }
                         delegation = nfs_start_delegation_return_locked(NFS_I(inode));
                         rcu_read_unlock();
 
                         err = nfs_end_delegation_return(inode, delegation, 0);
                         iput(inode);
+                        nfs_sb_deactive(server->super);
                         if (!err)
                                 goto restart;
                         set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
@@ -809,19 +821,30 @@ restart:
         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
                 list_for_each_entry_rcu(delegation, &server->delegations,
                                                                 super_list) {
+                        if (test_bit(NFS_DELEGATION_RETURNING,
+                                                &delegation->flags))
+                                continue;
                         if (test_bit(NFS_DELEGATION_NEED_RECLAIM,
                                                 &delegation->flags) == 0)
                                 continue;
-                        inode = nfs_delegation_grab_inode(delegation);
-                        if (inode == NULL)
+                        if (!nfs_sb_active(server->super))
                                 continue;
-                        delegation = nfs_detach_delegation(NFS_I(inode),
-                                        delegation, server);
+                        inode = nfs_delegation_grab_inode(delegation);
+                        if (inode == NULL) {
+                                rcu_read_unlock();
+                                nfs_sb_deactive(server->super);
+                                goto restart;
+                        }
+                        delegation = nfs_start_delegation_return_locked(NFS_I(inode));
                         rcu_read_unlock();
-
-                        if (delegation != NULL)
-                                nfs_free_delegation(delegation);
+                        if (delegation != NULL) {
+                                delegation = nfs_detach_delegation(NFS_I(inode),
+                                        delegation, server);
+                                if (delegation != NULL)
+                                        nfs_free_delegation(delegation);
+                        }
                         iput(inode);
+                        nfs_sb_deactive(server->super);
                         goto restart;
                 }
         }