NFS: Fix a deadlock with lazy umount
We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare()
and task->tk_ops->rpc_call_done() to call mntput() in any way, since
that will cause a deadlock when the call to rpc_shutdown_client() attempts
to wait on 'task' to complete.
We can avoid the above deadlock by moving calls to mntput to
task->tk_ops->rpc_release() callback, since at that time the task will be
marked as completed, and so rpc_shutdown_client won't attempt to wait on
it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 16844f9..e017040 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -323,7 +323,7 @@
data->inode = inode;
data->cred = msg.rpc_cred;
data->args.fh = NFS_FH(inode);
- data->args.context = ctx;
+ data->args.context = get_nfs_open_context(ctx);
data->args.offset = pos;
data->args.pgbase = pgbase;
data->args.pages = data->pagevec;
@@ -546,6 +546,7 @@
data->args.fh = NFS_FH(data->inode);
data->args.offset = 0;
data->args.count = 0;
+ data->args.context = get_nfs_open_context(dreq->ctx);
data->res.count = 0;
data->res.fattr = &data->fattr;
data->res.verf = &data->verf;
@@ -728,7 +729,7 @@
data->inode = inode;
data->cred = msg.rpc_cred;
data->args.fh = NFS_FH(inode);
- data->args.context = ctx;
+ data->args.context = get_nfs_open_context(ctx);
data->args.offset = pos;
data->args.pgbase = pgbase;
data->args.pages = data->pagevec;