On Wed, Jun 9, 2021 at 10:28 AM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > On Wed, 9 Jun 2021 at 08:08, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > > > On Tue, Jun 8, 2021 at 9:20 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > > > > > On Tue, 8 Jun 2021 at 17:33, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > > > > > > > On Tue, Jun 8, 2021 at 5:49 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > > > > > > > > > On Tue, 8 Jun 2021 at 16:37, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > > > > > > While you are here, do you think that will be sufficient for the on-disk format > > > > > > of overlay.xflags? > > > > > > > > > > > > struct ovl_xflags { > > > > > > __le32 xflags; > > > > > > __le32 xflags_mask; > > > > > > } > > > > > > > > > > I think I'd prefer a slightly more complex, but user friendlier > > > > > "+i,-a,..." format. > > > > > > > > > > > > > OK, but since this is not a merge, we'd only need: > > > > overlay.xflags = "ia..." > > > > > > > > Which is compatible with the format of: > > > > chattr =<xflags> <file> > > > > > > Fine. Not sure what xflags_mask would be useful for in your proposal, though. > > > > > > > The idea was that in the context of fileattr_get(), any specific xflag > > value can be one of: SET, CLEAR, REAL. > > > > For most inodes all flags are REAL (no xflags xattr) > > All flags but the 4 in OVL_FS_XFLAGS_MASK are always REAL > > (i.e. taken from fileattr_get() on real inode). > > > > If we ever decide to extend OVL_FS_XFLAGS_MASK, say to include > > DIRSYNC, then an upper inode with DIRSYNC that was in state > > REAL before upgrade would become CLEAR after upgrade unless > > we kept the old xflags_mask in xattr. > > > > With the string format, this is not a concern. > > Therefore, I like the string format better. > > Hmm, so if the attribute letters would have fixed places in the string > and clear attributes would be represented by a space or a "-" then > that would be similarly extensible. Just having a list of set > attribute letters would not allow having three states. > Right. Will do that. Thanks, Amir.