cifs: allow caller to specify completion op when allocating writedata

We'll need a different set of write completion ops when not writing out
of the pagecache.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 5fedf6c..f624c4d 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1684,7 +1684,8 @@
 		tofind = min((cifs_sb->wsize / PAGE_CACHE_SIZE) - 1,
 				end - index) + 1;
 
-		wdata = cifs_writedata_alloc((unsigned int)tofind);
+		wdata = cifs_writedata_alloc((unsigned int)tofind,
+					     cifs_writev_complete);
 		if (!wdata) {
 			rc = -ENOMEM;
 			break;