this patch does 2 things:
a) only do additional call outs if BDRV_BLOCK_ZERO is not already set.
b) use the newly introduced bdrv_has_discard_zeroes() to return the
zero state of an unallocated block. the used callout to
bdrv_has_zero_init() is only valid right after bdrv_create.
Reviewed-by: Eric Blake <ebl...@redhat.com>
Signed-off-by: Peter Lieven <p...@kamp.de>
---
block.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block.c b/block.c
index f56660d..032809a 100644
--- a/block.c
+++ b/block.c
@@ -3263,8 +3263,8 @@ static int64_t coroutine_fn
bdrv_co_get_block_status(BlockDriverState *bs,
return ret;
}
- if (!(ret & BDRV_BLOCK_DATA)) {
- if (bdrv_has_zero_init(bs)) {
+ if (!(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO)) {
+ if (bdrv_has_discard_zeroes(bs)) {
ret |= BDRV_BLOCK_ZERO;
} else if (bs->backing_hd) {
BlockDriverState *bs2 = bs->backing_hd;
--
1.7.9.5
