[PATCH] Updated jail mount/unmount patch

After implementing a suggestion from pjd_at_, a new version of the patch is
attached, now using a more universal solution - vn_fullpath_global() in
the mount part.

Dňa 28. 7. 2011 16:59, Martin Matuska wrote / napísal(a):
> Please review my attached patch.
>
> The patch fixes f_mntonname with mount/unmount inside a jail with allow.mount enabled.
> Filesystems mountable in a jail require the VFCF_JAIL flag (currently only ZFS).
>
> With this patch, mount and unmount works both with enforce_statfs = 0 and enforce_statfs = 1.
> I suggest disabling mount/unmount for jails with enforce_statfs = 2, as this is contradictory and does not play well with or without this patch.
>
> I have successfully tested this patch with ZFS, nullfs and tmpfs.
>
> To enable nullfs for a jail, you have to modify tmpfs/tmpfs_vfsops.c and recompile the tmpfs module:
> -VFS_SET(tmpfs_vfsops, tmpfs, 0);
> +VFS_SET(tmpfs_vfsops, tmpfs, VFCF_JAIL);
>
> To enable tmpfs for a jail, you have to modify nullfs/null_vfsops.c and recompile the nullfs module:
> -VFS_SET(null_vfsops, nullfs, VFCF_LOOPBACK);
> +VFS_SET(null_vfsops, nullfs, VFCF_LOOPBACK | VFCF_JAIL);
>
> The filesystems can be successfully mounted/unmounted inside a jail and also unmounted from the parent host without problems.
>
> The mount inside jail, a jail needs allow.mount=1 and enforce.statfs=0 or enforce.statfs=1, for more information see jail(8)
> I assume other filesystem not dealing with devices may work correctly with this patch, too (e.g. nfs).
>
> With jailed nullfs we can run tinderbox in a jail ;)
>
> Please review, comment and/or test my attached patch.
>
> Cheers,
> mm
-- 
Martin Matuska
FreeBSD committer
http://blog.vx.sk