NFSv4: Clean up the asynchronous delegation return

Reuse the state management thread in order to return delegations when we
get a callback.

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

1 files changed, 19 insertions, 54 deletions

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 21eda6c083d0..00c350c031b4 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -321,6 +321,12 @@ int nfs_inode_return_delegation(struct inode *inode)
         return err;
 }
 
+static void nfs_mark_return_delegation(struct nfs_client *clp, struct nfs_delegation *delegation)
+{
+        set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
+        set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+}
+
 /*
  * Return all delegations associated to a super block
  */
@@ -376,66 +382,25 @@ void nfs_handle_cb_pathdown(struct nfs_client *clp)
         nfs_client_mark_return_all_delegations(clp);
 }
 
-struct recall_threadargs {
-        struct inode *inode;
-        struct nfs_client *clp;
-        const nfs4_stateid *stateid;
-
-        struct completion started;
-        int result;
-};
-
-static int recall_thread(void *data)
-{
-        struct recall_threadargs *args = (struct recall_threadargs *)data;
-        struct inode *inode = igrab(args->inode);
-        struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
-        struct nfs_inode *nfsi = NFS_I(inode);
-        struct nfs_delegation *delegation;
-
-        daemonize("nfsv4-delegreturn");
-
-        nfs_msync_inode(inode);
-        down_write(&nfsi->rwsem);
-        spin_lock(&clp->cl_lock);
-        delegation = nfs_detach_delegation_locked(nfsi, args->stateid);
-        if (delegation != NULL)
-                args->result = 0;
-        else
-                args->result = -ENOENT;
-        spin_unlock(&clp->cl_lock);
-        complete(&args->started);
-        nfs_delegation_claim_opens(inode, args->stateid);
-        up_write(&nfsi->rwsem);
-        nfs_msync_inode(inode);
-
-        if (delegation != NULL)
-                nfs_do_return_delegation(inode, delegation, 1);
-        iput(inode);
-        module_put_and_exit(0);
-}
-
 /*
  * Asynchronous delegation recall!
  */
 int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
 {
-        struct recall_threadargs data = {
-                .inode = inode,
-                .stateid = stateid,
-        };
-        int status;
+        struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+        struct nfs_delegation *delegation;
 
-        init_completion(&data.started);
-        __module_get(THIS_MODULE);
-        status = kernel_thread(recall_thread, &data, CLONE_KERNEL);
-        if (status < 0)
-                goto out_module_put;
-        wait_for_completion(&data.started);
-        return data.result;
-out_module_put:
-        module_put(THIS_MODULE);
-        return status;
+        rcu_read_lock();
+        delegation = rcu_dereference(NFS_I(inode)->delegation);
+        if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
+                                sizeof(delegation->stateid.data)) != 0) {
+                rcu_read_unlock();
+                return -ENOENT;
+        }
+        nfs_mark_return_delegation(clp, delegation);
+        rcu_read_unlock();
+        nfs_delegation_run_state_manager(clp);
+        return 0;
 }
 
 /*