On Mon, 2007-04-16 at 23:07 +0200, Karel Zak wrote: > On Mon, Apr 16, 2007 at 10:39:46AM -0700, Ram Pai wrote: > > > This patch disambiguates multiple mount-instances of the same > > filesystem (or part of the same filesystem), by introducing a new > > interface /proc/mounts_new. The interface has the following format. > ^^^^^^^^^^^^^^ > ... odd name. What will be the name for a next generation? > "/proc/mounts_new_new"? :-) > that was the name I came up with 6 months back :-). Yes It should be something more appropriate. Maybe /proc/mounts_1 ? The next generation one would be /proc/mounts_2 ? Suggestion? > > 'cat /proc/mounts' shows the following: > > /dev/root /mnt ext2 rw 0 0 > > /dev/root /tmp1 ext2 rw 0 0 > > > > NOTE: The above mount entries, do not indicate that /tmp1 contains the same > > directory tree as /var/tmp. > > > > But 'cat /proc/mounts_new' shows us the following: > > 0x6200 /mnt /var ext2 rw 0 0 > > 0x6200 /tmp1 /var/tmp ext2 rw 0 0 > > Can't you purely and simply add the fsid= option to /proc/mounts? > > /dev/root /mnt ext2 rw,fsid=0x6200 0 0 > /dev/root /mnt ext2 rw,fsid=0x6200 0 0 > > I think you can do it without a negative impact to userspace. ok. > > > This patch introduces a new proc interface that exposes all the propagation > > trees within the namespace. > > Good idea. > > > It walks through each off the mounts in the namespace, and prints the following information. > > > > mount-id: a unique mount identifier > > dev-id : the unique device used to identify the device containing the filesystem > ^^^^ > Why not major:minor? Thinking about it, I feel we dont need this field at all. Basically we need a field that can be keyed-upon to find the corresponding record in /proc/mounts_1. mount-id can be used as the matching field, provided we add the mount-id field to /proc/mounts_1. agree? RP > > 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) > > > Example: > > Here is a sample output of cat /proc/$$/mounts_propagation > > > > 0xa917800 0x1 / / PRIVATE > > 0xa917200 0x6200 / / PRIVATE > > 0xa917180 0x3 /proc / PRIVATE > > 0xa917f80 0xa /dev/pts / PRIVATE > > 0xa917100 0x6210 /mnt / SHARED peer:0xa917100 > > 0xa917f00 0x6210 /tmp /1 SLAVE master:0xa917100 > > 0xa917900 0x6220 /mnt/2 / SHARED peer:0xa917900 > > Same thing (although the mounts_propagation makes more sense than > mount_new from my point of view). > > cat /proc/mounts (or /proc/$$/mounts) > > /dev/root /mnt ext2 rw,mid=0xa917100,did=0x6210,prop=SHARED,peer=0xa917100 > > > my $0.02... > > Karel > - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
