Provided by: bilibop-lockfs_0.5.0_i386 bug

NAME

       mount.lockfs - helper script for the mount command

SYNOPSIS

       mount.lockfs FILESYSTEM MOUNTPOINT [MOUNTFLAGS] -o MOUNTOPTIONS

DESCRIPTION

       /sbin/mount.lockfs  is  a  symlink to /lib/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
          details.

OPTIONS

       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:

       FILESYSTEM
              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.

       MOUNTPOINT
              Corresponding to the second field in fstab.

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

       -o MOUNTOPTIONS
              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.

FILES

       /etc/fstab
       /lib/bilibop/lockfs_mount_helper
       /usr/share/doc/bilibop-lockfs/README.Debian

SEE ALSO

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

AUTHOR

       This    manual    page    has   been   written   by   Bilibop   Project
       <quidame@poivron.org>.