Mini Shell

#!/bin/bash

# called by dracut
check() {
    local _rootdev
    # If our prerequisites are not met, fail anyways.
    require_binaries iscsi-iname iscsiadm iscsid || return 1

    # If hostonly was requested, fail the check if we are not actually
    # booting from root.

    is_iscsi() {
        local _dev=$1

        [[ -L "/sys/dev/block/$_dev" ]] || return
        cd "$(readlink -f "/sys/dev/block/$_dev")"
        until [[ -d sys || -d iscsi_session ]]; do
            cd ..
        done
        [[ -d iscsi_session ]]
    }

    [[ $hostonly ]] || [[ $mount_needs ]] && {
        pushd . >/dev/null
        for_each_host_dev_and_slaves is_iscsi || return 255
        popd >/dev/null
    }
    return 0
}

get_ibft_mod() {
    local ibft_mac=$1
    local iface_mac iface_mod
    # Return the iSCSI offload module for a given MAC address
    for iface_desc in $(iscsiadm -m iface | cut -f 2 -d ' '); do
        iface_mod=${iface_desc%%,*}
        iface_mac=${iface_desc#*,}
        iface_mac=${iface_mac%%,*}
        if [ "$ibft_mac" = "$iface_mac" ] ; then
            echo $iface_mod
            return 0
        fi
    done
}

install_ibft() {
    # When iBFT / iscsi_boot is detected:
    # - Use 'ip=ibft' to set up iBFT network interface
    #   Note: bnx2i is using a different MAC address of iSCSI offloading
    #         so the 'ip=ibft' parameter must not be set
    # - specify firmware booting cmdline parameter

    for d in /sys/firmware/* ; do
        if [ -d ${d}/ethernet0 ] ; then
            read ibft_mac < ${d}/ethernet0/mac
            ibft_mod=$(get_ibft_mod $ibft_mac)
        fi
        if [ -z "$ibft_mod" ] && [ -d ${d}/ethernet1 ] ; then
            read ibft_mac < ${d}/ethernet1/mac
            ibft_mod=$(get_ibft_mod $ibft_mac)
        fi
        if [ -d ${d}/initiator ] ; then
            if [ ${d##*/} = "ibft" ] && [ "$ibft_mod" != "bnx2i" ] ; then
                echo -n "rd.iscsi.ibft=1 "
            fi
            echo -n "rd.iscsi.firmware=1"
        fi
    done
}

install_iscsiroot() {
    local devpath=$1
    local scsi_path iscsi_lun session c d conn host flash
    local iscsi_session iscsi_address iscsi_port iscsi_targetname iscsi_tpgt
    local bootproto

    scsi_path=${devpath%%/block*}
    [ "$scsi_path" = "$devpath" ] && return 1
    iscsi_lun=${scsi_path##*:}
    [ "$iscsi_lun" = "$scsi_path" ] && return 1
    session=${devpath%%/target*}
    [ "$session" = "$devpath" ] && return 1
    iscsi_session=${session##*/}
    [ "$iscsi_session" = "$session" ] && return 1
    host=${session%%/session*}
    [ "$host" = "$session" ] && return 1
    iscsi_host=${host##*/}

    for flash in ${host}/flashnode_sess-* ; do
        [ -f "$flash" ] || continue
        [ ! -e "$flash/is_boot_target" ] && continue
        is_boot=$(cat $flash/is_boot_target)
        if [ $is_boot -eq 1 ] ; then
            # qla4xxx flashnode session; skip iBFT discovery
            iscsi_initiator=$(cat /sys/class/iscsi_host/${iscsi_host}/initiatorname)
            echo "rd.iscsi.initiator=${iscsi_initiator}"
            return;
        fi
    done

    for d in ${session}/* ; do
        case $d in
	    *connection*)
	        c=${d##*/}
	        conn=${d}/iscsi_connection/${c}
	        if [ -d ${conn} ] ; then
		    iscsi_address=$(cat ${conn}/persistent_address)
		    iscsi_port=$(cat ${conn}/persistent_port)
	        fi
	        ;;
	    *session)
	        if [ -d ${d}/${iscsi_session} ] ; then
                    iscsi_initiator=$(cat ${d}/${iscsi_session}/initiatorname)
		    iscsi_targetname=$(cat ${d}/${iscsi_session}/targetname)
	        fi
	        ;;
        esac
    done

    [ -z "$iscsi_address" ] && return
    local_address=$(ip -o route get to $iscsi_address | sed -n 's/.*src \([0-9a-f.:]*\).*/\1/p')
    ifname=$(ip -o route get to $iscsi_address | sed -n 's/.*dev \([^ ]*\).*/\1/p')

    # follow ifcfg settings for boot protocol
    for _path in \
        "/etc/sysconfig/network-scripts/ifcfg-$ifname" \
        "/etc/sysconfig/network/ifcfg-$ifname" \
    ; do
        [ -r "$_path" ] && bootproto=$(sed -n "s/BOOTPROTO='\?\([[:alpha:]]*6\?\)4\?/\1/p" "$_path")
    done

    if [ $bootproto ]; then
        printf 'ip=%s:%s ' ${ifname} ${bootproto}
    else
        printf 'ip=%s:static ' ${ifname}
    fi

    if [ -e /sys/class/net/$ifname/address ] ; then
        ifmac=$(cat /sys/class/net/$ifname/address)
        printf 'ifname=%s:%s ' ${ifname} ${ifmac}
    fi

    if [ -n "$iscsi_address" -a -n "$iscsi_targetname" ] ; then
        if [ -n "$iscsi_port" -a "$iscsi_port" -eq 3260 ] ; then
            iscsi_port=
        fi
        if [ -n "$iscsi_lun" -a "$iscsi_lun" -eq 0 ] ; then
            iscsi_lun=
        fi
        # In IPv6 case rd.iscsi.initatior= must pass address in [] brackets
        case "$iscsi_address" in
            *:*)
                iscsi_address="[$iscsi_address]"
                ;;
        esac
        # Must be two separate lines, so that "sort | uniq" commands later
        # can sort out rd.iscsi.initiator= duplicates
        echo "rd.iscsi.initiator=${iscsi_initiator}"
        echo "netroot=iscsi:${iscsi_address}::${iscsi_port}:${iscsi_lun}:${iscsi_targetname}"
        echo "rd.neednet=1"
    fi
    return 0
}


install_softiscsi() {
    [ -d /sys/firmware/ibft ] && return 0

    is_softiscsi() {
        local _dev=$1
        local iscsi_dev

        [[ -L "/sys/dev/block/$_dev" ]] || return
        iscsi_dev=$(cd -P /sys/dev/block/$_dev; echo $PWD)
        install_iscsiroot $iscsi_dev
    }

    for_each_host_dev_and_slaves_all is_softiscsi || return 255
    return 0
}

# called by dracut
depends() {
    echo network rootfs-block
}

# called by dracut
installkernel() {
    local _arch=$(uname -m)
    local _funcs='iscsi_register_transport'

    instmods bnx2i qla4xxx cxgb3i cxgb4i be2iscsi qedi
    hostonly="" instmods iscsi_tcp iscsi_ibft crc32c iscsi_boot_sysfs

    if [ "$_arch" = "s390" -o "$_arch" = "s390x" ]; then
        _s390drivers="=drivers/s390/scsi"
    fi

    dracut_instmods -o -s ${_funcs} =drivers/scsi ${_s390drivers:+"$_s390drivers"}
}

# called by dracut
cmdline() {
    local _iscsiconf=$(install_ibft)
    {
        if [ "$_iscsiconf" ] ; then
            echo ${_iscsiconf}
        else
            install_softiscsi
        fi
    } | sort | uniq
}

# called by dracut
install() {
    inst_multiple -o iscsiuio
    inst_libdir_file 'libgcc_s.so*'
    inst_multiple umount iscsi-iname iscsiadm iscsid

    inst_multiple -o \
        $systemdsystemunitdir/iscsid.socket \
        $systemdsystemunitdir/iscsid.service \
        $systemdsystemunitdir/iscsiuio.service \
        $systemdsystemunitdir/iscsiuio.socket \
        $systemdsystemunitdir/sockets.target.wants/iscsid.socket \
        $systemdsystemunitdir/sockets.target.wants/iscsiuio.socket

    if [[ $hostonly ]]; then
        inst_dir $(/usr/bin/find /etc/iscsi)
    else
        inst_simple /etc/iscsi/iscsid.conf
    fi

    # Detect iBFT and perform mandatory steps
    if [[ $hostonly_cmdline == "yes" ]] ; then
        local _iscsiconf=$(cmdline)
        [[ $_iscsiconf ]] && printf "%s\n" "$_iscsiconf" >> "${initdir}/etc/cmdline.d/95iscsi.conf"
    fi

    inst_hook cmdline 90 "$moddir/parse-iscsiroot.sh"
    inst_hook cleanup 90 "$moddir/cleanup-iscsi.sh"
    inst "$moddir/iscsiroot.sh" "/sbin/iscsiroot"
    if ! dracut_module_included "systemd"; then
        inst "$moddir/mount-lun.sh" "/bin/mount-lun.sh"
    else
        inst_multiple -o \
                      $systemdsystemunitdir/iscsi.service \
                      $systemdsystemunitdir/iscsid.service \
                      $systemdsystemunitdir/iscsid.socket \
                      $systemdsystemunitdir/iscsiuio.service \
                      $systemdsystemunitdir/iscsiuio.socket \
                      iscsiadm iscsid

        for i in \
                iscsid.socket \
                iscsiuio.socket \
            ; do
            systemctl -q --root "$initdir" enable "$i"
        done
        
        for i in \
                iscsid.service \
                iscsiuio.service \
            ; do
            systemctl -q --root "$initdir" add-wants basic.target "$i"
        done

        # Make sure iscsid is started after dracut-cmdline and ready for the initqueue
        mkdir -p "${initdir}/$systemdsystemunitdir/iscsid.service.d"
        (
            echo "[Unit]"
            echo "After=dracut-cmdline.service"
            echo "Before=dracut-initqueue.service"
        ) > "${initdir}/$systemdsystemunitdir/iscsid.service.d/dracut.conf"

        # The iscsi deamon does not need to wait for any storage inside initrd
        mkdir -p "${initdir}/$systemdsystemunitdir/iscsid.socket.d"
        (
            echo "[Unit]"
            echo "DefaultDependencies=no"
            echo "Conflicts=shutdown.target"
            echo "Before=shutdown.target sockets.target"
        ) > "${initdir}/$systemdsystemunitdir/iscsid.socket.d/dracut.conf"
        mkdir -p "${initdir}/$systemdsystemunitdir/iscsiuio.socket.d"
        (
            echo "[Unit]"
            echo "DefaultDependencies=no"
            echo "Conflicts=shutdown.target"
            echo "Before=shutdown.target sockets.target"
        ) > "${initdir}/$systemdsystemunitdir/iscsiuio.socket.d/dracut.conf"

    fi
    inst_dir /var/lib/iscsi
    dracut_need_initqueue
}