If we are growing the image and potentially using preallocation for the
new area, we need to make sure that no write requests are made to the
"preallocated" area which is [@old_size, @offset), not
[@offset, offset * 2 - @old_size).
Signed-off-by: Fam Zheng <f...@redhat.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
---
block/io.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/io.c b/block/io.c
index 9687da1ce9..e3e2d5286d 100644
--- a/block/io.c
+++ b/block/io.c
@@ -3113,7 +3113,8 @@ int coroutine_fn bdrv_co_truncate(BdrvChild *child,
int64_t offset,
}
bdrv_inc_in_flight(bs);
- tracked_request_begin(&req, bs, offset, new_bytes, BDRV_TRACKED_TRUNCATE);
+ tracked_request_begin(&req, bs, offset - new_bytes, new_bytes,
+ BDRV_TRACKED_TRUNCATE);
/* If we are growing the image and potentially using preallocation for the
* new area, we need to make sure that no write requests are made to it
--
2.17.1
