static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { BDRVParallelsState *s = bs->opaque; uint32_t idx, to_allocate, i; int64_t pos, space; pos = block_status(s, sector_num, nb_sectors, pnum); if (pos > 0) { return pos; } idx = sector_num / s->tracks; if (idx >= s->bat_size) { return -EINVAL; } to_allocate = DIV_ROUND_UP(sector_num + *pnum, s->tracks) - idx; space = to_allocate * s->tracks; if (s->data_end + space > bdrv_getlength(bs->file->bs) >> BDRV_SECTOR_BITS) { int ret; space += s->prealloc_size; if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) { ret = bdrv_pwrite_zeroes(bs->file, s->data_end << BDRV_SECTOR_BITS, space << BDRV_SECTOR_BITS, 0); } else { ret = bdrv_truncate(bs->file, (s->data_end + space) << BDRV_SECTOR_BITS); } if (ret < 0) { return ret; } } for (i = 0; i < to_allocate; i++) { s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier); s->data_end += s->tracks; bitmap_set(s->bat_dirty_bmap, bat_entry_off(idx + i) / s->bat_dirty_block, 1); } return bat2sect(s, idx) + sector_num % s->tracks; }