#!/bin/bash

#

# iscsi_offload

#

# Configure iSCSI offload engines for use with open-iscsi

# Usage:

#    iscsi_offload [-d | -f | -i <ipaddr> | -t ] <nic>

#

# Copyright (c) 2011 Hannes Reinecke, SUSE Labs

# This script is licensed under the GPL.

#

# The script creates an open-iscsi interface definition

# in the style <nic>-<module>, where <nic> matches the

# network interface passed on the commandline.

# If '-t' (test mode) is passed as an option, the script

# will not create nor modify any setting but just print

# the currently active ones.

#

# Currently the script works with Broadcom (bnx2i) and

# Chelsio T3 (cxgbi) iSCSI offload engines.

# Should work with Chelsio T4, but has not been tested.

# ServerEngines (be2iscsi) and QLogic (qla4xxx) can only

# be configured via BIOS, open-iscsi support is still in

# development.

#

#

# Return codes:

#    0: Success

#    1: Invalid command line parameter

#    2: iSCSI offloading not supported

#    3: Error during module loading

#    4: Cannot configure interface via iscsiadm, use BIOS setup

#    5: internal error running iscsiadm

#

# Output:

#    <mac> [none|dhcp|ip <ipaddr>|ibft]

# where

#    <mac>: MAC Address of the iSCSI offload engine

#    none:  No IP configuration set for the iSCSI offload engine

#    dhcp:  iSCSI offload engine configured for DHCP

#    ip:    iSCSI offload engine configured with static IP address <ipaddr>

#    ibft:  iSCSI offload engine configured from iBFT values

#

#

# Figure out the MAC address of the iSCSI offload engine

# corresponding to a NIC from a given PCI device.

# bnx2 is using one PCI device per port for both network and iSCSI offloading

# cxgb3 is using one PCI device for everything.

#

iscsi_macaddress_from_pcidevice()

{

    local path=$1

    local if=$2

    local h

    local host

    for h in $path/host* ; do

	if [ -d "$h" ] ; then

	    host=${h##*/}

	    read netdev < /sys/class/iscsi_host/$host/netdev

	    if [ "$netdev" = "$IFNAME" ] ; then

		read mac < /sys/class/iscsi_host/$host/hwaddress

		if [ "$mac" != "00:00:00:00:00:00" ] ; then

		    echo "$mac"

		fi

		break;

	    fi

	fi

    done

}

#

# Figure out the MAC address of the iSCSI offload engine

# corresponding to a NIC from a given PCI function.

# It is assumed that the MAC address of the iSCSI offload

# engine is equal of the MAC address of the NIC plus one.

# Suitable for be2iscsi and qla4xxx

#

iscsi_macaddress_from_pcifn()

{

    local path=$1

    local if=$2

    local h

    local host

    local ifmac

    ifmac=$(ip addr show dev $if | sed -n 's/ *link\/ether \(.*\) brd.*/\1/p')

    m5=$(( 0x${ifmac##*:} ))

    m5=$(( $m5 + 1 ))

    ifmac=$(printf "%s:%02x" ${ifmac%:*} $m5)

    for host in /sys/class/iscsi_host/host* ; do

	if [ -L "$host" ] ; then

	    read mac < $host/hwaddress

	    if [ "$mac" = "$ifmac" ] ; then

		echo "$mac"

		break;

	    fi

	fi

    done

}

update_iface_setting() {

    local iface="$1"

    local name="$2"

    local value="$3"

    iface_value=$(iscsiadm -m iface -I $iface | sed -n "s/$name = \(.*\)/\1/p")

    if [ "$iface_value" = "<empty>" ] ; then

	iface_value=

    fi

    if [ "$iface_value" != "$value" ] ; then

	if ! iscsiadm -m iface -I $iface -o update -n "$name" -v "$value" ; then

	    return 1

	fi

    fi

    return 0

}

while getopts di:t options ; do

    case $options in

	d ) mode=dhcp;;

	i ) mode=static

	    optaddr=$OPTARG

	    ;;

	f ) mode=firmware;;

	t ) dry_run=1;;

	?)  printf "Usage: %s [-d|-t|-i ipaddr|-f] ifname\n" $0

	    exit 1;;

    esac

done

shift $(($OPTIND - 1))

IFNAME=$1

ibft_mode="none"

if [ -z "$IFNAME" ] ; then

    echo "No interface specified"

    exit 1

fi

if [ "$dry_run" ] ; then

    if [ "$mode" = "dhcp" ] ; then

	echo "'-t' specified, ignoring '-d'"

	mode=

    elif [ "$mode" = "static" ] ; then

	echo "'-t' specified, ignoring '-s'"

	mode=

    fi

fi

if [ ! -L /sys/class/net/$IFNAME ] ; then

    echo "Interface $IFNAME not found"

    exit 1

fi

if [ "$optaddr" ] && ! ip route get $optaddr ; then

    echo "Invalid IP address $optaddr"

    exit 1

fi

if [ "$dry_run" ] ; then

    mode=

fi

ifpath=$(cd -P /sys/class/net/$IFNAME; echo $PWD)

pcipath=$(cd -P $ifpath/device; echo $PWD)

if [ -d $pcipath ] ; then

    drvlink=$(readlink $pcipath/driver)

    driver=${drvlink##*/}

fi

if [ -z "$driver" ] ; then

    echo "No driver found for interface $IFNAME"

    exit 1

fi

case "$driver" in

    bnx2*)

	mod=bnx2i

	;;

    cxgb*)

	mod=cxgb3i

	;;

    be2*)

	mod=be2iscsi

	;;

    qla*)

	mod=qla4xxx

	;;

esac

if [ -z "$mod" ] ; then

    echo "iSCSI offloading not supported on interface $IFNAME"

    exit 2

fi

# Check if the required modules are already loaded

loaded=$(sed -n "/^$mod/p" /proc/modules)

if [ -z "$loaded" ] ; then

    modprobe $mod

fi

loaded=$(sed -n "/^$mod/p" /proc/modules)

if [ -z "$loaded" ] ; then

    echo "Loading of $mod.ko failed, please check dmesg"

    exit 3

fi

# Get the correct MAC address for the various devices

if [ "$mod" = "bnx2i" ] ; then

    mac=$(iscsi_macaddress_from_pcidevice $pcipath $IFNAME)

elif [ "$mod" = "cxgb3i" ] ; then

    mac=$(iscsi_macaddress_from_pcidevice $pcipath $IFNAME)

elif [ "$mod" = "be2iscsi" ] ; then

    mac=$(iscsi_macaddress_from_pcifn $pcipath $IFNAME)

elif [ "$mod" = "qla4xxx" ] ; then

    mac=$(iscsi_macaddress_from_pcifn $pcipath $IFNAME)

fi

if [ -z "$mac" ] ; then

    echo "iSCSI offloading not supported on interface $IFNAME"

    exit 2

fi

gen_iface="$mod.$mac"

ioe_iface="${IFNAME}-${mod}"

# Get existing settings

if iscsiadm -m iface -I $ioe_iface > /dev/null 2>&1 ; then

    ioe_mac=$(iscsiadm -m iface -I $ioe_iface 2> /dev/null| sed -n "s/iface\.hwaddress = \(.*\)/\1/p")

    ioe_mod=$(iscsiadm -m iface -I $ioe_iface 2> /dev/null| sed -n "s/iface\.transport_name = \(.*\)/\1/p")

    ipaddr=$(iscsiadm -m iface -I $ioe_iface 2> /dev/null| sed -n "s/iface\.ipaddress = \(.*\)/\1/p")

    if [ "$ipaddr" == "<empty>" ] ; then

	ipaddr=

    fi

elif [ "$mod" = "be2iscsi" ] ; then

    ioe_mac=$mac

    ioe_mod=$mod

else

    # Create new interface

    iscsiadm -m iface -I $ioe_iface --op=new 2> /dev/null

    ioe_mac=

    ioe_mod=

    ipaddr=

fi

if [ -z "$dry_run" ] ; then

    if [ "$ioe_mac" != "$mac" ] ; then

	if [ -n "$ioe_mac" ] ; then

	    echo "Warning: Updating MAC address on iface $ioe_iface"

	fi

	update_iface_setting $ioe_iface iface.hwaddress "$mac"

    fi

    if [ "$ioe_mod" != "$mod" ] ; then

	if [ -n "$ioe_mod" ] ; then

	    echo "Warning: Update transport on iface $ioe_iface"

	fi

	update_iface_setting $ioe_iface iface.transport_name "$mod"

    fi

elif [ -z "$ipaddr" ] ; then

    ipaddr=$(iscsiadm -m iface -I $gen_iface 2> /dev/null| sed -n "s/iface\.ipaddress = \(.*\)/\1/p")

    if [ "$ipaddr" = "<empty>" ] ; then

	ipaddr=

    fi

elif [ "$ioe_mod" != "$mod" ] ; then

    echo "Warning: Transport mismatch on iface $ioe_iface: $ioe_mod should be $mod"

fi

# Check iBFT setting

for d in /sys/firmware/* ; do

    [ -d $d ] || continue

    [ -d $d/ethernet0 ] || continue

    iboot_dir=$d

done

if [ -n "$iboot_dir" ] && [ -d "$iboot_dir" ] ; then

    for if in ${iboot_dir}/ethernet* ; do

	read ibft_mac < $if/mac

	[ "$ibft_mac" = "$mac" ] || continue

	ibft_origin=0

	[ -f ${if}/origin ] && read ibft_origin < $if/origin

	if [ "$ibft_origin" -eq 1 ] ; then

	    ibft_mode="static"

	elif [ "$ibft_origin" -eq 3 ] ; then

	    ibft_mode="dhcp"

	fi

	[ -f $if/dhcp ] && read ibft_dhcp < $if/dhcp

	if [ -n "$ibft_dhcp" -a "$ibft_mode" != "dhcp" ] ; then

	    ibft_mode=dhcp

	fi

	if [ "$ibft_mode" = "dhcp" ] ; then

	    ibft_ipaddr="0.0.0.0"

	    ibft_gateway=

	    ibft_mask=

	    break

	fi

	[ -f $if/ip-addr ] && read ibft_ipaddr < $if/ip-addr

	[ -f $if/gateway ] && read ibft_gateway < $if/gateway

	[ -f $if/subnet-mask ] && read ibft_mask < $if/subnet-mask

	break

    done

fi

if [ -z "$optaddr" ] && [ "$ibft_ipaddr" ] ; then

    optaddr=$ibft_ipaddr

fi

# Check if the interface needs to be configured

if [ -z "$mode" ] ; then

    if [ "$ibft_mode" != "none" ] ; then

	echo "$mac ibft"

	mode="ibft"

    elif [ -z "$ipaddr" ] ; then

	echo "$mac none"

	mode="none"

    elif [ "$ipaddr" = "0.0.0.0" ] ; then

	echo "$mac dhcp"

	ipaddr=

	mode="dhcp"

    else

	echo "$mac ip $ipaddr"

	mode="static"

    fi

    [ "$dry_run" ] && exit 0

elif [ "$mode" = "dhcp" ] ; then

    if [ "$ipaddr" = "0.0.0.0" ] ; then

	echo "$mac dhcp"

	exit 0

    fi

    optaddr="0.0.0.0"

elif [ "$mode" = "static" ] && [ "$ipaddr" = "$optaddr" ] ; then

    echo "$mac ip $ipaddr"

    exit 0

fi

if [ "$mod" = "be2iscsi" ] ; then

    exit 4

fi

if ! update_iface_setting $ioe_iface iface.ipaddress "$optaddr" ; then

    echo "Failed to set IP address: $?"

    exit 1

fi

if ! update_iface_setting $gen_iface iface.ipaddress "$optaddr" ; then

    echo "Failed to set IP address for generic interface: $?"

    exit 1

fi

if ! update_iface_setting $ioe_iface iface.gateway "$ibft_gateway" ; then

    echo "Failed to set gateway address: $?"

    exit 1

fi

if ! update_iface_setting $gen_iface iface.gateway "$ibft_gateway" ; then

    echo "Failed to set gateway address for generic interface: $?"

    exit 1

fi

if ! update_iface_setting $ioe_iface iface.subnet_mask "$ibft_mask" ; then

    echo "Failed to set subnet mask: $?"

    exit 1

fi

if ! update_iface_setting $gen_iface iface.subnet_mask "$ibft_mask" ; then

    echo "Failed to set subnet mask for generic interface: $?"

    exit 1

fi

if [ "$mod" = "qla4xxx" ] ; then

    iscsiadm -m iface -H $mac -o applyall

fi

ip link set dev $IFNAME up

exit 0