Re: request for patches: showing mount options

Karel Zak
2007-07-31T22:21:57Z

On Tue, Jul 31, 2007 at 10:19:57AM -0400, Chuck Lever wrote:
> The removal of /etc/mtab in favor of /proc/mounts is a new requirement,
> and is not as trivial as you might hope. Internally the NFS client
> represents the mount options as a binary data structure, and it contains
> only the information that has traditionally been passed into the kernel
> by the current mount command. The user-space-only options are not
> passed to the kernel nor stored in the data structure.
>
> Adding facilities to store information about every possible mount
> option, including the user-space-only ones, will take a bit of time, but
> is possible, if not straightforward. We just have to understand all the
> dependencies.

I still have doubts. The removal of /etc/mtab is nice, but a little
unreal wish. Do we really want to store non-kernel data (options) in
kernel? What about options that are not closely related to any
filesystem -- for example "loop="?

Maybe we can replace /etc/mtab with something more useful
(e.g. /var/run/mount/<mntid>.tab) for really user-space-only information.

It doesn't mean that Miklos's audit of all filesystems and request
for patches is bad thing. The /proc/mounts has to provide complete
information at least about kernel mount options.

Karel

--
Karel Zak <kzak@redhat.com>