#!/bin/sh
#
# Copyright 2009 Red Hat, Inc.
# License: GPLv2
# Author: Dan Horák <dhorak@redhat.com>
#
# unblock devices listed in various config files and wait until they are ready
#
# it uses dasd and zfcp config file
# config file syntax:
# deviceno   options
# or
# deviceno   WWPN   FCPLUN
#
# also processes the system ccw config file and network interface configurations
#

DASDCONFIG=/etc/dasd.conf
ZFCPCONFIG=/etc/zfcp.conf
ZNETCONFIG=/etc/ccw.conf
BLACKLIST=/proc/cio_ignore
VERBOSE=
PATH=/bin:/usr/bin:/sbin:/usr/sbin
ALL_DEVICES=

usage()
{
    echo "$0 [-h|--help] [-V|--verbose]"
    exit 1
}

# accepts single device, comma-separated lists and dash separated ranges and their combinations
free_device()
{
    local DEV

    [ -z "$1" ] && return

    DEV=$(echo $1 | tr "A-Z" "a-z")
    
    [ $VERBOSE ] && echo "Freeing device(s) $DEV"
    if [ echo "free $DEV" > $BLACKLIST 2> /dev/null ]; then
	echo "Error: can't free device(s) $DEV"
    else
	if [ -z $ALL_DEVICES ]; then
	    ALL_DEVICES=$DEV
	else
	    ALL_DEVICES="$ALL_DEVICES,$DEV"
	fi
    fi
}

# wait until a device appears on the ccw bus
wait_on_device()
{
    local DEVICE_ONLINE DEV
    
    [ -z "$1" ] && return
    
    DEV=$1
    DEVICE_ONLINE=/sys/bus/ccw/devices/$DEV/online
    
    [ $VERBOSE ] && echo "Waiting on device $DEV"
    [ -f "$DEVICE_ONLINE" ] && return

    for t in 1 2 3 4 5
    do
	sleep $t
	[ -f "$DEVICE_ONLINE" ] && return
    done
    echo "Error: device $DEV still not ready"
}

# check how we were called
case $(basename "$0") in
    "dasd_cio_free")
	CONFIG=$DASDCONFIG
	MODE=dasd
	;;
    "zfcp_cio_free")
	CONFIG=$ZFCPCONFIG
	MODE=zfcp
	;;
    "znet_cio_free")
	CONFIG=$ZNETCONFIG
	MODE=znet
	;;
    *)
	echo "Error: unknown alias '$CMD'."
	echo "Supported aliases are dasd_cio_free, zfcp_cio_free and znet_cio_free."
	exit 1
	;;
esac

# process command line options
if [ $# -gt 0 ]; then
    case $1 in
	-V|--verbose)
	    VERBOSE=yes
	    shift
	    ;;
	-h|--help)
	    usage
	    ;;
	*)
	    echo "Error: unknown option $1"
	    usage
	    ;;
    esac
fi

if [ ! -f $BLACKLIST ]; then
    echo "Error: $BLACKLIST kernel interface doesn't exist"
    exit 2
fi

if [ $MODE = "dasd" -o $MODE = "zfcp" ]; then
    # process the config file
    if [ -f "$CONFIG" ]; then
        while read line; do
	    case $line in
		\#*) ;;
		*)
		    [ -z "$line" ] && continue
		    set $line
		    free_device $1
		    ;;
	    esac
	done < $CONFIG
    fi
fi

if [ $MODE = "dasd" ]; then
    # process the device list defined as option for the dasd module
    DEVICES=$(modprobe --showconfig | grep "options[[:space:]]\+dasd_mod" | \
	sed -e 's/.*[[:space:]]dasd=\([^[:space:]]*\).*/\1/' -e 's/([^)]*)//g' \
	-e 's/nopav\|nofcx\|autodetect\|probeonly//g' -e 's/,,/,/g' -e 's/^,//' -e 's/,$//')

    free_device $DEVICES
fi

if [ $MODE = "znet" ]; then
    # process the config file
    if [ -f "$CONFIG" ]; then
        while read line; do
	    case $line in
		\#*) ;;
		*)
		    [ -z "$line" ] && continue
		    # grep 2 or 3 channels from beginning of each line
		    DEVICES=$(echo $line | egrep -i -o "^([0-9]\.[0-9]\.[a-f0-9]+,){1,2}([0-9]\.[0-9]\.[a-f0-9]+)")
		    free_device $DEVICES
		    ;;
	    esac
	done < $CONFIG
    fi
    # process channels from network interface configurations
    for line in $(egrep -i -h "^[[:space:]]*SUBCHANNELS=['\"]?([0-9]\.[0-9]\.[a-f0-9]+,){1,2}([0-9]\.[0-9]\.[a-f0-9]+)['\"]?([[:space:]]+#|[[:space:]]*$)" /etc/sysconfig/network-scripts/ifcfg-* 2> /dev/null)
    do
	eval "$line"
        free_device $SUBCHANNELS
    done
fi

# wait until recently unblocked devices are ready
# at this point we know the content of ALL_DEVICES is syntacticly correct
IFS=","
set $ALL_DEVICES
while [ "$1" ]
do
    DEV="$1"
    IFS="."

    # get the lower bound for range or get the single device
    LOWER=${DEV%%-*}
    read -a L <<< "$LOWER"
    if [ ${#L[@]} -eq 1 ]; then
        L[2]=${L[0]}
        L[0]=0
        L[1]=0
    fi

    # get the upper bound for range or get the single device
    UPPER=${DEV##*-}
    read -a U <<< "$UPPER"
    if [ ${#U[@]} -eq 1 ]; then
        U[2]=${U[0]}
        U[0]=0
        U[1]=0
    fi

    # iterate thru all devices
    for (( i=0x${L[0]}; i<=0x${U[0]}; i++ )); do
    for (( j=0x${L[1]}; j<=0x${U[1]}; j++ )); do
    for (( k=0x${L[2]}; k<=0x${U[2]}; k++ )); do
	wait_on_device "$(printf %x.%x.%04x $i $j $k)"
    done
    done
    done

    # go to the next device
    shift
done