1 files changed, 42 insertions, 0 deletions

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 00c350c031b4..e75f2f8c5245 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -43,6 +43,27 @@ static void nfs_free_delegation(struct nfs_delegation *delegation)
                 put_rpccred(cred);
 }
 
+void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
+{
+        set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
+}
+
+int nfs_have_delegation(struct inode *inode, int flags)
+{
+        struct nfs_delegation *delegation;
+        int ret = 0;
+
+        flags &= FMODE_READ|FMODE_WRITE;
+        rcu_read_lock();
+        delegation = rcu_dereference(NFS_I(inode)->delegation);
+        if (delegation != NULL && (delegation->type & flags) == flags) {
+                nfs_mark_delegation_referenced(delegation);
+                ret = 1;
+        }
+        rcu_read_unlock();
+        return ret;
+}
+
 static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state)
 {
         struct inode *inode = state->inode;
@@ -188,6 +209,7 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
         delegation->change_attr = nfsi->change_attr;
         delegation->cred = get_rpccred(cred);
         delegation->inode = inode;
+        delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
         spin_lock_init(&delegation->lock);
 
         spin_lock(&clp->cl_lock);
@@ -382,6 +404,26 @@ void nfs_handle_cb_pathdown(struct nfs_client *clp)
         nfs_client_mark_return_all_delegations(clp);
 }
 
+static void nfs_client_mark_return_unreferenced_delegations(struct nfs_client *clp)
+{
+        struct nfs_delegation *delegation;
+
+        rcu_read_lock();
+        list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
+                if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
+                        continue;
+                set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
+                set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+        }
+        rcu_read_unlock();
+}
+
+void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
+{
+        nfs_client_mark_return_unreferenced_delegations(clp);
+        nfs_delegation_run_state_manager(clp);
+}
+
 /*
  * Asynchronous delegation recall!
  */