On 2020/7/13 04:37, Jens Axboe wrote: > On 7/12/20 11:47 AM, Coly Li wrote: >> For some block devices which large capacity (e.g. 8TB) but small io_opt >> size (e.g. 8 sectors), in bcache_device_init() the stripes number calcu- >> lated by, >> DIV_ROUND_UP_ULL(sectors, d->stripe_size); >> might be overflow to the unsigned int bcache_device->nr_stripes. >> >> This patch uses an unsigned long variable to store DIV_ROUND_UP_ULL() >> and after the value is checked to be available in unsigned int range, >> sets it to bache_device->nr_stripes. Then the overflow is avoided. > > Does that work on 32-bit, where sizeof(unsigned long) == 4? > I will post v2 to explicit use uint64_t. Thanks for the remind. Coly Li
