#!/bin/sh

SCRIPT_NAME=$0


if [ $# -lt 2 ]; then
	cat <<EOF
Updates the exported LUN of a mapped VTD (Virtual Target Device) device in a VIOS. 
This script will set the device to "Defined" stated and then rescan the Virtual Adapter:
 rmdev -l vtd
 odmget | odmchange
 cfgmgr -l vhostX

Usage:
	$SCRIPT_NAME <vtd> <newlun>
EOF
	exit
fi

vtd=$1
lun=$2

# Check the vtd
if ! lsdev -l $vtd | grep -q "Virtual Target Device"; then
	echo "$SCRIPT_NAME: The device '$vtd' does not exists or is not a Virtual Target Device" 1>&2
	exit 1
fi

# Check the lun number
lun=$(echo $lun | tr a-f A-F | awk '/0x[0-9A-F]{16}/ {print}')
if [ -z "$lun" ]; then 
	echo "$SCRIPT_NAME: Lun must have format "0xNNNNNNNNNNNNNNNN" (16 digits)" 1>&2
	exit 1
fi

# check that lun changes
actual_lun=$(odmget -q "name=$vtd and attribute=LogicalUnitAddr" CuAt| \
             sed -n 's/.*value = "\(.*\)"/\1/p' | tr a-f A-F)
if [ "$lun" == "$actual_lun" ]; then
	echo "$SCRIPT_NAME: lun already is $lun for '$vtd'. No change." 1>&2
	exit 0
fi

# change the lun. 
#  1. set the VTD to defined
#  2. update odm
#  4. cfgmgr vadapter
vadapter=$(lsdev -Cl $vtd -F parent)
echo "Updating the lun of $vadapter.$vtd..."

rmdev -l $vtd  > /dev/null
odmget -q "name=$vtd and attribute=LogicalUnitAddr" CuAt | \
	sed "s/value =.*/value = \"$lun\"/" | \
	odmchange -q "name=$vtd and attribute=LogicalUnitAddr" -o CuAt 
cfgmgr -l $vadapter

lsattr -El $vtd