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authorEric Blake <eblake@redhat.com>2017-10-11 22:47:19 -0500
committerKevin Wolf <kwolf@redhat.com>2017-10-26 14:45:57 +0200
commit8cbf74b23cafd1bcee5fdef769f8e94ace43935f (patch)
tree12d75d78b97511b0497f10893a6eeeb5b4eee810 /block/qcow2.c
parent88e63df21490a43f430820c66b043018db96b1d4 (diff)
downloadqemu-8cbf74b23cafd1bcee5fdef769f8e94ace43935f.tar.gz
qcow2: Reduce is_zero() rounding
Now that bdrv_is_allocated accepts non-aligned inputs, we can remove the TODO added in earlier refactoring. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c12
1 files changed, 3 insertions, 9 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 29d0a50955..fbf9464d3a 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2976,22 +2976,16 @@ static bool is_zero(BlockDriverState *bs, int64_t offset, int64_t bytes)
{
int64_t nr;
int res;
- int64_t start;
-
- /* TODO: Widening to sector boundaries should only be needed as
- * long as we can't query finer granularity. */
- start = QEMU_ALIGN_DOWN(offset, BDRV_SECTOR_SIZE);
- bytes = QEMU_ALIGN_UP(offset + bytes, BDRV_SECTOR_SIZE) - start;
/* Clamp to image length, before checking status of underlying sectors */
- if (start + bytes > bs->total_sectors * BDRV_SECTOR_SIZE) {
- bytes = bs->total_sectors * BDRV_SECTOR_SIZE - start;
+ if (offset + bytes > bs->total_sectors * BDRV_SECTOR_SIZE) {
+ bytes = bs->total_sectors * BDRV_SECTOR_SIZE - offset;
}
if (!bytes) {
return true;
}
- res = bdrv_block_status_above(bs, NULL, start, bytes, &nr, NULL, NULL);
+ res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
return res >= 0 && (res & BDRV_BLOCK_ZERO) && nr == bytes;
}