On 3/30/2022 9:18 AM, Darrick J. Wong wrote: > On Wed, Mar 30, 2022 at 08:49:29AM -0700, Christoph Hellwig wrote: >> On Wed, Mar 30, 2022 at 06:58:21PM +0800, Shiyang Ruan wrote: >>> As the code I pasted before, pmem driver will subtract its ->data_offset, >>> which is byte-based. And the filesystem who implements ->notify_failure() >>> will calculate the offset in unit of byte again. >>> >>> So, leave its function signature byte-based, to avoid repeated conversions. >> >> I'm actually fine either way, so I'll wait for Dan to comment. > > FWIW I'd convinced myself that the reason for using byte units is to > make it possible to reduce the pmem failure blast radius to subpage > units... but then I've also been distracted for months. :/ > Yes, thanks Darrick! I recall that. Maybe just add a comment about why byte unit is used? thanks! -jane > --D