block: Add bdrv_get_block_status_above

Like bdrv_is_allocated_above, this function follows the backing chain until seeing
BDRV_BLOCK_ALLOCATED.  Base is not included.

Reimplement bdrv_is_allocated on top.

[Initialized bdrv_co_get_block_status_above() ret to 0 to silence
mingw64 compiler warning about the unitialized variable.  assert(bs !=
base) prevents that case but I suppose the program could be compiled
with -DNDEBUG.
--Stefan]

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Fam Zheng 2015-06-08 13:56:07 +08:00 committed by Stefan Hajnoczi
parent e0cf11f31c
commit ba3f0e2545
2 changed files with 49 additions and 11 deletions

View file

@ -372,6 +372,10 @@ bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum);
int64_t bdrv_get_block_status_above(BlockDriverState *bs,
BlockDriverState *base,
int64_t sector_num,
int nb_sectors, int *pnum);
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
int *pnum);
int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,