On Wed, Mar 25, 2020 at 05:27:38AM +0000, Damien Le Moal wrote: > > At least for a normal file system that is absolutely not true. If > > zonefs is so special it might be better of just using a slightly tweaked > > copy of blkdev_direct_IO rather than using iomap. > > It would be very nice to not have to add this direct BIO use case in zonefs > since that would be only for writes to sequential zones while all other > operations use iomap. So instead of this, what about using a flag as Dave > suggested (see below comment too) ? Given how special the use case is I'm not sure overloading iomap is a good idea. Think of how a "normal" zone aware file system would use iomap and not of this will apply. OTOH the "simple" single bio code in __blkdev_direct_IO_simple is less than 100 lines of code. I think having a specialized code base for a specialized use case might be better than overloading generic code with tons of flags. > > I don't think the iocb is the right interface for passing this > > kind of information. We currently pass a bool wait to iomap_dio_rw > > which really should be flags. I have a pending patch for that. > > Is that patch queued in iomap or xfs tree ? Could you point us to it please ? It isn't queued up anywhere yet.
