On Tue, 2017-06-13 at 23:47 -0700, Christoph Hellwig wrote: > On Tue, Jun 13, 2017 at 06:24:32AM -0400, Jeff Layton wrote: > > That's definitely what I want for the endgame here. My plan was to add > > this flag for now, and then eventually reverse it (or drop it) once all > > or most filesystems are converted. > > > > We can do it that way from the get-go if you like. It'll mean tossing in > > a patch add this flag to all filesystems that have an fsync operation > > and that use the pagecache, and then gradually remove it from them as we > > convert them. > > > > Which method do you prefer? > > Please do it from the get-go. Or in fact figure out if we can get > away without it entirely. Moving the error reporting into ->fsync > should help greatly with that, so what's missing after that? In this smaller set, it's only really used for DAX. In the larger patch series I have (which needs updating on top of this), there are other things that key off of it: sync_file_range: ->fsync isn't called directly there, and I think we probably want similar semantics to fsync() for it JBD2: will try to re-set the error after clearing it with filemap_fdatawait. That's problematic with the new infrastructure so we need some way to avoid it. What I think I'll do for now is add a new FS_DAX_WB_ERRSEQ flag that will go away by the end of the series. As the need arises for a similar flag in other areas, I'll add them then. The overall goal is not to need these flags. It may take a bit of time to get there though. Thanks for the review so far! -- Jeff Layton <jlayton@xxxxxxxxxx>
