Re: (subset) [PATCH 0/4] Add the ability to query mount options in statmount

[Christian Brauner <brauner@kernel.org>]

On Mon, 24 Jun 2024 15:40:49 -0400, Josef Bacik wrote:
> Currently if you want to get mount options for a mount and you're using
> statmount(), you still have to open /proc/mounts to parse the mount options.
> statmount() does have the ability to store an arbitrary string however,
> additionally the way we do that is with a seq_file, which is also how we use
> ->show_options for the individual file systems.
> 
> Extent statmount() to have a flag for fetching the mount options of a mount.
> This allows users to not have to parse /proc mount for anything related to a
> mount.  I've extended the existing statmount() test to validate this feature
> works as expected.  As you can tell from the ridiculous amount of silly string
> parsing, this is a huge win for users and climate change as we will no longer
> have to waste several cycles parsing strings anymore.
> 
> [...]

* Changed to only call sb->d_op->show_options() so we only show filesystem
  mount options.
* Fixed/tweaked selftests to parse /proc/self/mountinfo directly and look for
  mount options, skipping over vfs generic superblock mount options.
* Since Karel is fine with keeping "," let's keep it.

---

Applied to the vfs.mount branch of the vfs/vfs.git tree.
Patches in the vfs.mount branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.mount

[1/4] fs: rename show_mnt_opts -> show_vfsmnt_opts
      https://git.kernel.org/vfs/vfs/c/429fc05aefd3
[3/4] fs: export mount options via statmount()
      https://git.kernel.org/vfs/vfs/c/f363afa8cbe0
[4/4] sefltests: extend the statmount test for mount options
      https://git.kernel.org/vfs/vfs/c/06bedc037f74