On 12/28/23 11:12, Alexander Ivanov wrote:
> There is no necessity to search to the end of the bitmap. Limit the search
> area as cluster_index + count.
>
> Add cluster_end variable to avoid its calculation in a few places.
>
> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> ---
> block/parallels.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/block/parallels.c b/block/parallels.c
> index ae524f1820..4470519656 100644
> --- a/block/parallels.c
> +++ b/block/parallels.c
> @@ -182,13 +182,14 @@ int parallels_mark_used(BlockDriverState *bs, unsigned long *bitmap,
> uint32_t bitmap_size, int64_t off, uint32_t count)
> {
> BDRVParallelsState *s = bs->opaque;
> - uint32_t cluster_index = host_cluster_index(s, off);
> + uint32_t cluster_end, cluster_index = host_cluster_index(s, off);
> unsigned long next_used;
> - if (cluster_index + count > bitmap_size) {
> + cluster_end = cluster_index + count;
> + if (cluster_end > bitmap_size) {
> return -E2BIG;
> }
> - next_used = find_next_bit(bitmap, bitmap_size, cluster_index);
> - if (next_used < cluster_index + count) {
> + next_used = find_next_bit(bitmap, cluster_end, cluster_index);
> + if (next_used < cluster_end) {
> return -EBUSY;
> }
> bitmap_set(bitmap, cluster_index, count);
Reviewed-by: Denis V. Lunev <den@openvz.org>