Re: Adding subroot information to /proc/mounts, or obtaining that through other means

["H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>]

Ram Pai wrote:
> 
> Peter, I am not working on it currently. But i am interested in getting
> it done. I have the seed set of patches which had Al Viro's ideas
> incorporated. Infact those patches were sent on lkml 2 months back.
> Shall we start with those patches?
> 

Okay, so what I see in your patches are:

> > path-from-root: mount point of the mount from /
> > path-from-root-of-its-sb: path from its own root dentry.
> > propagation-flag: SHARED, SLAVE, UNBINDABLE, PRIVATE
> > peer-mount-id: the mount-id of its peer mount (if this mount is shared)
> > master-mount-id: the mount-id of its master mount (if this mount is
slave)

Other than cosmetic, I don't see anything terribly wrong with this,
although getting a flag when the directory is overmounted would be nice.

I guess I suggest a single comma-separated field with flags and optional
":argument":

	private
	shared:<peer>
	slave:<master>
	unbindable
	overmounted

So we could end up with something like:

rootfs / rootfs rw 0 0 0:1 / 1 private,overmounted

... where 1 is the mnt_id (sequence number).

[Please see my other comments in this thread... basically I believe we
should just add fields to /proc/mounts.]

	-hpa