NFSv4: nfs_client_return_marked_delegations can't flush data
Since even filemap_flush() needs to lock pages that are dirty, we
cannot risk calling it from the state manager context. Therefore,
we need to move the call to filemap_flush() to
nfs_async_inode_return_delegation().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index a19cb5a..bd3a960 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -316,6 +316,10 @@
* nfs_client_return_marked_delegations - return previously marked delegations
* @clp: nfs_client to process
*
+ * Note that this function is designed to be called by the state
+ * manager thread. For this reason, it cannot flush the dirty data,
+ * since that could deadlock in case of a state recovery error.
+ *
* Returns zero on success, or a negative errno value.
*/
int nfs_client_return_marked_delegations(struct nfs_client *clp)
@@ -340,11 +344,9 @@
server);
rcu_read_unlock();
- if (delegation != NULL) {
- filemap_flush(inode->i_mapping);
+ if (delegation != NULL)
err = __nfs_inode_return_delegation(inode,
delegation, 0);
- }
iput(inode);
if (!err)
goto restart;
@@ -542,6 +544,8 @@
struct nfs_client *clp = server->nfs_client;
struct nfs_delegation *delegation;
+ filemap_flush(inode->i_mapping);
+
rcu_read_lock();
delegation = rcu_dereference(NFS_I(inode)->delegation);