#!/bin/sh

NAME=${DEVNAME#/dev/}
QDB_KEY="/qubes-block-devices/$NAME"
# Trailing slash is intentional - it will remove whole directory, instead of
# single base entry
qubesdb-rm "$QDB_KEY/"
qubesdb-write /qubes-block-devices ''

# If device was connected to some VM - detach it
# Notice: this can be run also in VM, so we cannot use xl...

device_detach() {
    xs_path=$1

    xenstore-write $xs_path/online 0 $xs_path/state 5

    # Wait for backend to finish dev shutdown
    try=30
    # -lt will break loop also when 'state' will be empty
    while [ "`xenstore-read $xs_path/state 2> /dev/null`" -lt 6 ]; do
        try=$[ $try - 1 ]
        [ "$try" -le 0 ] && break
        sleep 0.1
    done
    xenstore-rm $xs_path
}

# update info about underlying devices of device-mapper (if any)
# at this stage device-mapper is already removed, so can't check what devices
# were used there
udevadm trigger --subsystem-match=block

for XS_DEV_PATH in `xenstore-ls -f backend/vbd | grep 'backend/vbd/[0-9]*/[0-9]* ' | cut -f 1 -d ' '`; do
    CUR_DEVICE=`xenstore-read "$XS_DEV_PATH/params"`
    if [ "$CUR_DEVICE" == "$DEVNAME" ]; then
        device_detach "$XS_DEV_PATH"
        exit 0
    fi
done