On Mon, Aug 31, 2020 at 5:52 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > On Mon, Aug 31, 2020 at 4:47 PM cgxu <cgxu519@xxxxxxxxxxxx> wrote: > > > > On 8/30/20 7:33 PM, Amir Goldstein wrote: > > > Interesting direction, not sure if this is workable. > > > I don't know enough about mm to say. > > > > > > But what about the rest of the operations? > > > Did you go over them and decide that overlay doesn't need to implement them? > > > I doubt it, but if you did, please document that. > > > > I did some check for rest of them, IIUC ->fault will be enough for this > > special case (shared read-only mmap with no upper), I will remove > > ->page_mkwrite in v2. Hmm, so this is just for that specific corner case? Not a generic shared mmap implementation? > > Ok I suppose you checked that ->map_pages is not relevant? > > > > > # I do not consider support ->huge_fault in current stage due to many fs > > cannot support DAX properly. > > > > BTW, do you know who should I add to CC list for further deep review of > > this code? fadevel-list? > > > > fsdevel would be good, but I would wait for initial feedback from Miklos > before you post v2... I could dig into the details of page fault handling, but that's not an area that I'm intimately familiar with. So yeah, a high level description of what happens on mmap, page fault, write fault, etc... would be really appreciated. Thanks, Miklos
