At Thu, 18 Apr 2013 19:48:52 +0800,
Liu Yuan wrote:
>
> +static coroutine_fn int
> +sd_co_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
> + int *pnum)
> +{
> + BDRVSheepdogState *s = bs->opaque;
> + SheepdogInode *inode = &s->inode;
> + unsigned long start = sector_num * SECTOR_SIZE / SD_DATA_OBJ_SIZE, idx,
It looks better to use BDRV_SECTOR_SIZE . I'd suggest preparing
another patch to replace all the SECTOR_SIZE with BDRV_SECTOR_SIZE.
> + end = start + (nb_sectors * SECTOR_SIZE) /
> SD_DATA_OBJ_SIZE;
Using 'start' to calculate 'end' is wrong because 'start' may be
rounded down.
> +
> + for (idx = start; idx <= end; idx++) {
> + if (inode->data_vdi_id[idx] == 0) {
> + break;
> + }
> + }
> + if (idx == start) {
> + *pnum = SD_DATA_OBJ_SIZE / SECTOR_SIZE;
Isn't it better to set the longest length of the unallocated sectors?
> + return 0;
> + }
> +
> + *pnum = (idx - start) * SD_DATA_OBJ_SIZE / SECTOR_SIZE;
> + return 1;
> +}
> +
Thanks,
Kazutaka
