imsm_check() {
   case $1 in
    container )
      grep -s "$(((418 * $2)/2)) blocks super external:imsm" /proc/mdstat > /dev/null || {
   		echo >&2 "ERROR correctly formed container not found"; cat /proc/mdstat; exit 1;}
      ;;
    member )
      member=$2
      num_disks=$3
      level=$4
      size=$5
      offset=$6
      err=0

      eval `stat -L -c "let major=0x%t; let minor=0x%T;" $member`
      sysfs=/sys/dev/block/${major}:${minor}
      if [ ! -f ${sysfs}/md/array_state ]; then
           echo "member array $member not found" >&2
           cat /proc/mdstat >&2
           exit 1
      fi
      for i in `seq 0 $((num_disks-1))`
      do
         _offset=`cat ${sysfs}/md/rd${i}/offset`
         if [ $offset -ne $((_offset/2)) ]; then
	    echo "offset mismatch expected $offset got $_offset" >&2
            err=$((err+1))
         fi
         _size=`cat ${sysfs}/md/rd${i}/size`
         if [ $size -ne $_size ]; then
	    echo "offset mismatch expected $size got $_size" >&2
            err=$((err+1))
         fi
      done

      if [ $err -gt 0 ]; then
          echo "$member failed check" >&2
          cat /proc/mdstat >&2
	  mdadm -E /dev/loop0 >&2
          exit 1
      fi
      ;;
    * ) echo >&2 ERROR unknown check $1 ; exit 1;
   esac
}

export IMSM_DEVNAME_AS_SERIAL=1
export IMSM_NO_PLATFORM=1
container=/dev/md/container
member0=/dev/md/vol0
member1=/dev/md/vol1
member2=/dev/md/vol2
member3=/dev/md/vol3
member4=/dev/md/vol4


# create raid arrays with varying degress of overlap
mdadm -CR $container -e imsm -n 6 $dev0 $dev1 $dev2 $dev3 $dev4 $dev5
imsm_check container 6

size=1910
level=1
num_disks=2
mdadm -CR $member0 $dev0 $dev1 -n $num_disks -l $level -z $size
mdadm -CR $member1 $dev1 $dev2 -n $num_disks -l $level -z $size
mdadm -CR $member2 $dev2 $dev3 -n $num_disks -l $level -z $size
mdadm -CR $member3 $dev3 $dev4 -n $num_disks -l $level -z $size
mdadm -CR $member4 $dev4 $dev5 -n $num_disks -l $level -z $size

offset=0
imsm_check member $member0 $num_disks $level $size $offset
offset=$((offset+size+2048))
imsm_check member $member1 $num_disks $level $size $offset
offset=$((offset+size+2048))
imsm_check member $member2 $num_disks $level $size $offset
offset=$((offset+size+2048))
imsm_check member $member3 $num_disks $level $size $offset
# at this point there should be more freespace at the start of the disk
# than the end
offset=0
imsm_check member $member4 $num_disks $level $size $offset