Provided by: bilibop-lockfs_0.6.3_amd64 bug


       mount.lockfs - helper script for the mount command




       /usr/sbin/mount.lockfs  is  a  symlink to /usr/libexec/bilibop/lockfs_mount_helper.  It is
       used as an helper program by the mount(8) command for the 'lockfs' filesystem type entries
       in  /etc/fstab.   This  script cannot be run manually, and fails if the root filesystem is
       not already managed by bilibop-lockfs.  The expected way to run it and how it does its job
       are the followings:

       1. Enable  bilibop-lockfs:  set the BILIBOP_LOCKFS variable to true in bilibop.conf(5) and
          reboot the computer; or reboot the computer and append the 'lockfs' kernel parameter to
          the boot commandline.

       2. One  time  the  future  '/'  is  set  as  an  union filesystem mountpoint from into the
          initramfs environment, the temporary and writable fstab(5) on it is modified to replace
          filesystem  types  of  some entries by 'lockfs'.  Options are also modified to remember
          the original fstype.

       3. One time the union mount is the new root filesystem, initscripts are executed: fstab(5)
          is parsed by 'mount -a', and then mount(8) calls mount.lockfs with the proper arguments
          when a 'lockfs' fstype is encountered.

       4. mount.lockfs parses arguments and checks if the  filesystem  has  been  whitelisted  in
          bilibop.conf(5),  or not. If it is the case, the filesystem is mounted normally and the
          fstab entry is modified to reflect the actual mount call. If neither the filesystem nor
          the  mountpoint  have  been  whitelisted,  then the filesystem is mounted elsewhere and
          readonly, a temporary filesystem is mounted with proper options, size, permissions  and
          ownership,  and an aufs or overlay filesystem (depending on the version of your kernel)
          is  mounted  on  the  MOUNTPOINT  given  as  argument  with  the   lower/readonly   and
          upper/writable  branches  previously  set.  The  fstab entry is replaced by three lines
          reflecting the actual mount calls. If something fails,  mount.lockfs  acts  as  if  the
          filesystem   was   whitelisted.   See  /usr/share/doc/bilibop-lockfs/README.Debian  for


       lockfs_mount_helper uses options and arguments as they are given by mount(8) after it  has
       parsed  the  corresponding  fstab(5) entry. So, options and arguments are mandatory, mount
       flags are optional, and all come in the following order:

              Corresponding to the first field in fstab. This  must  be  a  block  device,  or  a
              symlink to a block device. If this field is given with one of the UUID=* or LABEL=*
              formats, then the mount command translates it  to  the  corresponding  device  name
              before to call the helper program.

              Corresponding to the second field in fstab.

              Generic flags passed to the mount commandline (the most usual being -v and -n).

              Corresponding  to  the  fourth  field in fstab. The mount options are parsed by the
              helper script: if fstype=* is encountered, it is removed from the options and  used
              to  mount  the  readonly branch with this filesystem type. If ro, noexec, nosuid or
              nodev options are encountered, they are added to the list of mount options  of  the
              writable branch.




       aufs(5), bilibop(7), bilibop.conf(5), fstab(5), mount(8)


       This manual page has been written by Bilibop Project <>.