On Mon, Mar 27 2017, Bart Van Assche wrote:

On Mon, 2017-03-20 at 16:43 -0400, Christoph Hellwig wrote:

quoted

+	u64 sector = blk_rq_pos(rq) >> (ilog2(sdp->sector_size) - 9);
+	u32 nr_sectors = blk_rq_sectors(rq) >> (ilog2(sdp->sector_size) - 9);

Although I know this is an issue in the existing code and not something
introduced by you: please consider using logical_to_sectors() instead of
open-coding this function. Otherwise this patch looks fine to me.

The downside of doing that is that we still call ilog2() twice, which
sucks. Would be faster to cache ilog2(sector_size) and use that in the
shift calculation.

-- 
Jens Axboe