commit 0e77514678f66cde28a00a7618c9d20c88c92a5a
author Milton D. Miller II <miltonm@us.ibm.com> Wed Jan 20 14:57:54 2016 -0600
committer Milton D. Miller II <miltonm@us.ibm.com> Thu Jan 28 15:45:20 2016 -0600
tree 7cc0284b25a6de5725b6c2137dcb21c5f3e6969c
parent 1af7dcca3b1e9e4904b3a386ccb18b8526da9ba9

Create obmc-phosphor-initfs startup and shutdown scripts

This recipe holds the key scripts for an initramfs image.
Written in sh to run with busybox, these three scripts handle
mounting, unmounting, and updating a set of mtd partitions to
form a read-write overlay on a read-only compressed base.

The init script will mount the base sysfs, proc, and devtmpfs as
well as run.  It copies the filesystem to run/initramfs to create
the shutdown and update environment.  It then mounts a base
read-only and read-write file system and then an overlay of them
combined, then continues with chroot into the overlay and execute
the normal /sbin/init.

The shutdown script will unmount the remaining nodev and root
filesystems from oldroot where systemd-shutdown pivots the old
file system, then looks for image- files. If any are found it
invokes update otherwise it performs the final reboot, powerdown,
or kexec, or halt.

The update script will attempt to mount the read/write overlay
and preserve selected files and directories based on a whitelist.
It then unmounts that fs and writes all image files to their
named mtd partition using flashcp, mounts and restores the saved
files, and finally unmounts the fs and performs the final reboot,
shutdown, kexec, or halt.

Signed-off-by: Milton Miller <miltonm@us.ibm.com>