On Tue, Jan 17, 2023 at 11:21:38PM -0800, Christoph Hellwig wrote: > On Sun, Jan 15, 2023 at 09:29:58AM -0800, Darrick J. Wong wrote: > > I don't have any objections to pulling everything except patches 8 and > > 10 for testing this week. > > That would be great. I now have a series to return the ERR_PTR > from __filemap_get_folio which will cause a minor conflict, but > I think that's easy enough for Linux to handle. Ok, done. > > > > 1. Does zonefs need to revalidate mappings? The mappings are 1:1 so I > > don't think it does, but OTOH zone pointer management might complicate > > that. > > Adding Damien. > > > 2. How about porting the writeback iomap validation to use this > > mechanism? (I suspect Dave might already be working on this...) > > What is "this mechanism"? Do you mean the here removed ->iomap_valid > ? writeback calls into ->map_blocks for every block while under the > folio lock, so the validation can (and for XFS currently is) done > in that. Moving it out into a separate method with extra indirect > functiona call overhead and interactions between the methods seems > like a retrograde step to me. Sorry, I should've been more specific -- can xfs writeback use the validity cookie in struct iomap and thereby get rid of struct xfs_writepage_ctx entirely? > > 2. Do we need to revalidate mappings for directio writes? I think the > > answer is no (for xfs) because the ->iomap_begin call will allocate > > whatever blocks are needed and truncate/punch/reflink block on the > > iolock while the directio writes are pending, so you'll never end up > > with a stale mapping. > > Yes. Er... yes as in "Yes, we *do* need to revalidate directio writes", or "Yes, your reasoning is correct"? --D
