[arch-releng] [RFC] [PATCH] [archiso] Make a list of used block devices

[Dieter Plaetinck]

On Wed, 22 Feb 2012 08:08:10 -0300
Gerardo Exequiel Pozzi <vmlinuz386 at yahoo.com.ar> wrote:

> On 02/22/2012 04:39 AM, Dieter Plaetinck wrote:
> > On Tue, 21 Feb 2012 20:01:30 -0300
> > Gerardo Exequiel Pozzi<vmlinuz386 at yahoo.com.ar>  wrote:
> >
> >> NOTE: Not tested yet, but should work(tm).
> >>
> >> This list includes block devices of ( /run/archiso/used_block_devices ):
> >> * Boot medium [archisodevice] (only if no copytoram= is used)
> >> * Loop medium [img_dev] (only if no copytoram= is used)
> >> * COW space [cowdevice] (only if cowdevice= is used (no tmpfs is used))
> >> * Loop devices used for SquashFS images.
> >> * Loop devices used for device-mapper devices (two per each dm-device, one RO{*.fs} and one RW{*.cow})
> >>
> >> Aditionally all loop devices except for backing COW files, all are setup as read-only.
> >>
> >> In configs/releng profile, a symlink is made at boot-time for AIF:
> >> /run/aif/ignore_devs ->  /run/archiso/used_block_devices
> >> ---
> >>   archiso/hooks/archiso                              |   20 ++++++++++++++++----
> >>   archiso/hooks/archiso_loop_mnt                     |    3 ++-
> >>   .../rc.d/functions.d/symlink_used_block_devices    |    7 +++++++
> >>   3 files changed, 25 insertions(+), 5 deletions(-)
> >>   create mode 100644 configs/releng/root-image/etc/rc.d/functions.d/symlink_used_block_devices
> >>
> >> diff --git a/archiso/hooks/archiso b/archiso/hooks/archiso
> >> index 3518d16..22b67e9 100644
> >> --- a/archiso/hooks/archiso
> >> +++ b/archiso/hooks/archiso
> >> @@ -10,7 +10,8 @@ _mnt_fs() {
> >>
> >>       mkdir -p "${newroot}${mnt}"
> >>
> >> -    ro_dev=$(losetup --find --show "${img}")
> >> +    ro_dev=$(losetup --find --show --read-only "${img}")
> >> +    echo ${ro_dev}>>  /run/archiso/used_block_devices
> >>       ro_dev_size=$(blockdev --getsz ${ro_dev})
> >>
> >>       if [[ "${cow_persistent}" == "P" ]]; then
> >> @@ -30,6 +31,7 @@ _mnt_fs() {
> >>       fi
> >>
> >>       rw_dev=$(losetup --find --show "/run/archiso/cowspace/${cow_directory}/${img_name}.cow")
> >> +    echo ${rw_dev}>>  /run/archiso/used_block_devices
> >>
> >>       echo "0 ${ro_dev_size} snapshot ${ro_dev} ${rw_dev} ${cow_persistent} 8" | dmsetup create ${dm_snap_name}
> >>
> >> @@ -39,6 +41,7 @@ _mnt_fs() {
> >>           launch_interactive_shell
> >>       else
> >>           echo "/dev/mapper/${dm_snap_name} ${mnt} auto defaults 0 0">>  ${newroot}/etc/fstab
> >> +        echo /dev/mapper/${dm_snap_name}>>  /run/archiso/used_block_devices
> >>       fi
> >>   }
> >>
> >> @@ -46,7 +49,8 @@ _mnt_fs() {
> >>   _mnt_sfs() {
> >>       local img="${1}"
> >>       local mnt="${2}"
> >> -    local img_fullname="${img##*/}";
> >> +    local img_fullname="${img##*/}"
> >> +    local sfs_dev
> >>
> >>       mkdir -p "${mnt}"
> >>
> >> @@ -60,7 +64,9 @@ _mnt_sfs() {
> >>           msg "done."
> >>       fi
> >>       msg ":: Mounting '${img}' (SquashFS) to '${mnt}'"
> >> -    if ! mount -r "${img}" "${mnt}"&>  /dev/null ; then
> >> +    sfs_dev=$(losetup --find --show --read-only "${img}")
> >> +    echo ${sfs_dev}>>  /run/archiso/used_block_devices
> >> +    if ! mount -r "${sfs_dev}" "${mnt}"&>  /dev/null ; then
> >>           echo "ERROR: while mounting '${img}' to '${mnt}'"
> >>           launch_interactive_shell
> >>       fi
> >> @@ -137,7 +143,12 @@ run_hook() {
> >>   archiso_mount_handler() {
> >>       local newroot="${1}"
> >>
> >> -    mountpoint -q "/run/archiso/bootmnt" || _mnt_dev "${archisodevice}" "/run/archiso/bootmnt" "-r"
> >> +    if ! mountpoint -q "/run/archiso/bootmnt"; then
> >> +        _mnt_dev "${archisodevice}" "/run/archiso/bootmnt" "-r"
> >> +        if [[ "${copytoram}" != "y" ]]; then
> >> +            echo $(readlink -f ${archisodevice})>>  /run/archiso/used_block_devices
> >> +        fi
> >> +    fi
> >>
> >>       if [[ ! -f "${aitab}" ]]; then
> >>           echo "ERROR: '${aitab}' file does not exist."
> >> @@ -170,6 +181,7 @@ archiso_mount_handler() {
> >>
> >>       if [[ -n "${cow_device}" ]]; then
> >>           _mnt_dev "${cow_device}" "/run/archiso/cowspace" "-r"
> >> +        echo $(readlink -f ${cow_device})>>  /run/archiso/used_block_devices
> >>           mount -o remount,rw "/run/archiso/cowspace"
> >>       else
> >>           msg ":: Mounting /run/archiso/cowspace (tmpfs) filesystem, size=${cowspace_size}..."
> >> diff --git a/archiso/hooks/archiso_loop_mnt b/archiso/hooks/archiso_loop_mnt
> >> index 664f3a5..808100d 100644
> >> --- a/archiso/hooks/archiso_loop_mnt
> >> +++ b/archiso/hooks/archiso_loop_mnt
> >> @@ -15,7 +15,7 @@ archiso_loop_mount_handler () {
> >>       msg ":: Setup a loop device from ${img_loop} located at device ${img_dev}"
> >>       _mnt_dev "${img_dev}" "/run/archiso/img_dev" "-r"
> >>
> >> -    if ! _dev_loop=$(losetup --find --show "/run/archiso/img_dev/${img_loop}"); then
> >> +    if ! _dev_loop=$(losetup --find --show --read-only "/run/archiso/img_dev/${img_loop}"); then
> >>           echo "ERROR: Setting loopback device for file '/run/archiso/img_dev/${img_loop}'"
> >>           launch_interactive_shell
> >>       fi
> >> @@ -27,5 +27,6 @@ archiso_loop_mount_handler () {
> >>           umount /run/archiso/img_dev
> >>       else
> >>           echo ${_dev_loop}>  /run/archiso/img_dev_loop
> >> +        echo $(readlink -f ${img_dev})>>  /run/archiso/used_block_devices
> >>       fi
> >>   }
> >> diff --git a/configs/releng/root-image/etc/rc.d/functions.d/symlink_used_block_devices b/configs/releng/root-image/etc/rc.d/functions.d/symlink_used_block_devices
> >> new file mode 100644
> >> index 0000000..e2b9fc1
> >> --- /dev/null
> >> +++ b/configs/releng/root-image/etc/rc.d/functions.d/symlink_used_block_devices
> >> @@ -0,0 +1,7 @@
> >> +symlink_used_block_devices()
> >> +{
> >> +    mkdir /run/aif
> >> +    ln -s /run/archiso/used_block_devices /run/aif/ignore_devs
> >> +}
> >> +
> >> +add_hook multi_end symlink_used_block_devices
> > Hey G,
> > seems like there's some small edits in here that have nothing to do with the actual block device listing changeset?
> >
> > Dieter
> >
> Yes, --read-only loops.
> 

seems to me like you need 3 commits:
1) for syntactical changes, only this:
-    local img_fullname="${img##*/}";
+    local img_fullname="${img##*/}"
2) for the read only loop devices
3) for the used_block_devices stuff

Dieter