From: Liu Yuan <tailai...@taobao.com>
The 'qemu-img convert -h' advertise that the default cache mode is
'writeback', while in fact it is 'unsafe'.
This patch 1) changes the cache mode as 'writeback' and 2) explicitly
calls bdrv_flush() to flush the dirty bits.
2) is needed because some backend storage doesn't have a self-flush
mechanism(for e.g., sheepdog), so we need to call bdrv_flush() to make
sure the image is really writen to the storage instead of hanging around
writeback cache forever.
Signed-off-by: Liu Yuan <tailai...@taobao.com>
---
qemu-img.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/qemu-img.c b/qemu-img.c
index 6a61ca8..f96230b 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -644,7 +644,7 @@ static int img_convert(int argc, char **argv)
fmt = NULL;
out_fmt = "raw";
- cache = "unsafe";
+ cache = "writeback";
out_baseimg = NULL;
compress = 0;
for(;;) {
@@ -1036,6 +1036,9 @@ out:
free_option_parameters(param);
qemu_vfree(buf);
if (out_bs) {
+ if (ret == 0) {
+ bdrv_flush(out_bs);
+ }
bdrv_delete(out_bs);
}
if (bs) {
--
1.7.8.2
