Making this option available even before implementing it will let
converting tests easier: in coming patches they can specify the option
already when necessary, before we actually write code to lock the
images.

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 block/file-posix.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/block/file-posix.c b/block/file-posix.c
index ade71db..2114720 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -392,6 +392,11 @@ static QemuOptsList raw_runtime_opts = {
             .type = QEMU_OPT_STRING,
             .help = "host AIO implementation (threads, native)",
         },
+        {
+            .name = "locking",
+            .type = QEMU_OPT_BOOL,
+            .help = "lock the file",
+        },
         { /* end of list */ }
     },
 };
-- 
2.9.3