On Thu, Apr 16, 2026 at 03:07:12PM +0200, Christian Brauner wrote: > On Sat, 28 Mar 2026 23:22:21 +0600, Dorjoy Chowdhury wrote: > > I came upon this "Ability to only open regular files" uapi feature > > suggestion > > from > > https://uapi-group.org/kernel-features/#ability-to-only-open-regular-files > > and thought it would be something I could do as a first patch and get to > > know the kernel code a bit better. > > > > The following filesystems have been tested by building and booting the > > kernel > > x86 bzImage in a Fedora 43 VM in QEMU. I have tested with OPENAT2_REGULAR > > that > > regular files can be successfully opened and non-regular files (directory, > > fifo etc) > > return -EFTYPE. > > - btrfs > > - NFS (loopback) > > - SMB (loopback) > > > > [...] > > - I've added an explanation why OPENAT2_REGULAR is only needed for some > ->atomic_open() implementers but not others. What I don't like is that > we need all that custom handling in there but it's managable. > > - I dropped the topmost style conversions. They really don't belong > there and if we switch to something better we should use (1 << <nr>). > > - I split the EFTYPE errno introduction into a separate patch.
So I've massaged this series a bit in that I moved OPENAT2_REGULAR into the upper 64-bit and internally use a __O_REGULAR bit. After having thought about it makes a lot more sense to move the openat2() only features into the upper 32-bit for the uapi space. I also ported the selftests to the TEST* framework to fit with Aleksa's recent rework.
