On Tue, Oct 24, 2017 at 09:46:15AM +0200, Christoph Hellwig wrote: > On Tue, Oct 24, 2017 at 03:16:36AM +0100, Al Viro wrote: >>> Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") >>> Signed-off-by: Greg Edwards <gedwards@xxxxxxx> >> >> That smells like a nasty source of overhead, especially on SMP boxen... > > We could just use __disk_get_part similar to the partition remapping, > or just pass the block_device to guard_bio_eod. Do you have a preference? __disk_get_part would be isolated to guard_bio_eod. If we pass in the block_device, it would also touch all the mpage_bio_submit callers.