Dan Williams <dan.j.williams@xxxxxxxxx> writes: > On Fri, Apr 15, 2016 at 11:06 AM, Jeff Moyer <jmoyer@xxxxxxxxxx> wrote: >> Dan Williams <dan.j.williams@xxxxxxxxx> writes: >> >>>>> There's a lot of special casing here, so you might consider adding >>>>> comments. >>>> >>>> Correct - maybe we should reconsider wrapper-izing this? :) >>> >>> Another option is just to skip dax_do_io() and this special casing >>> fallback entirely if errors are present. I.e. only attempt dax_do_io >>> when: IS_DAX() && gendisk->bb && bb->count == 0. >> >> So, if there's an error anywhere on the device, penalize all I/O (not >> just writes, and not just on sectors that are bad)? I'm not sure that's >> a great plan, either. >> > > If errors are rare how much are we actually losing in practice? How long is a piece of string? > Moreover, we're going to do the full badblocks lookup anyway when we > call ->direct_access(). If we had that information earlier we can > avoid this fallback dance. None of the proposed approaches looks clean to me. I'll go along with whatever you guys think is best. I am in favor of wrapping up all that duplicated code, though. Cheers, Jeff -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>