diff --git a/block/io.c b/block/io.c index 01e3477a77..4ee8fe5465 100644 --- a/block/io.c +++ b/block/io.c @@ -2409,9 +2409,10 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs, if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { ret |= BDRV_BLOCK_ALLOCATED; } else if (want_zero && bs->drv->supports_backing) { - if (bs->backing) { - BlockDriverState *bs2 = bs->backing->bs; - int64_t size2 = bdrv_getlength(bs2); + BlockDriverState *cow_bs = bdrv_cow_bs(bs); + + if (cow_bs) { + int64_t size2 = bdrv_getlength(cow_bs); if (size2 >= 0 && offset >= size2) { ret |= BDRV_BLOCK_ZERO; @@ -2479,7 +2480,7 @@ static int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs, bool first = true; assert(bs != base); - for (p = bs; p != base; p = backing_bs(p)) { + for (p = bs; p != base; p = bdrv_filter_or_cow_bs(p)) { ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map, file); if (ret < 0) { @@ -2553,7 +2554,7 @@ int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, int bdrv_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file) { - return bdrv_block_status_above(bs, backing_bs(bs), + return bdrv_block_status_above(bs, bdrv_filter_or_cow_bs(bs), offset, bytes, pnum, map, file); } @@ -2563,9 +2564,9 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int ret; int64_t dummy; - ret = bdrv_common_block_status_above(bs, backing_bs(bs), false, offset, - bytes, pnum ? pnum : &dummy, NULL, - NULL); + ret = bdrv_common_block_status_above(bs, bdrv_filter_or_cow_bs(bs), false, + offset, bytes, pnum ? pnum : &dummy, + NULL, NULL); if (ret < 0) { return ret; } @@ -2628,7 +2629,7 @@ int bdrv_is_allocated_above(BlockDriverState *top, break; } - intermediate = backing_bs(intermediate); + intermediate = bdrv_filter_or_cow_bs(intermediate); } *pnum = n;