Display LUN information for ASM devices RHEL 5 and 6

I know close to nothing about Perl.  This script was created on RHEL 5 and I wanted the functionality to be extended to RHEL 6.  

In regards to our script the significant differences between RHEL 5 and 6 are:

RHEL5
/dev/mpath     -- path to multipath devices
 \_                   -- identifier for multipath device

RHEL6
/dev/mapper   -- path to multipath devices
  |-                   -- identifier for multipath device
  `-                  -- identifier for multipath device
 

#!/usr/bin/perl

@rhelver = `cat /etc/redhat-release`;
$rhelver[0] =~ / (\d\.\d) /;     
$RELEASE = $1;

# ARRAY OF HDS ARRAYS
$sxm_arrays = {
  '726a'=>'ITSHDS05',
  '71c9'=>'ITSHDS06',
  '61bc'=>'ITSHDS04',
  '4ed0'=>'ITSHDS01',
  '5b68'=>'ITSHDS02',
  '03da'=>'ORION1',
  '03f6'=>'TITAN1',
  'ac75'=>'ATLAS',
  'ba9e'=>'CAPELLA',
  '2924'=>'REGULUS'
};

# BUILD ARRAY BASED ON OUTPUT FROM multipath COMMAND
open MPATH,"multipath -ll -v2|" or die "can't fork: $!";
while (<MPATH>) {
  chomp;
  if (m/^(mpath\d+) \(\w*(\w{4})\w{4}(\w{2})(\w{2})\) (\S+) /) {
    $mpath_id="$sxm_arrays->{$2}_$3$4";
    $ldev{$mpath_id}="$3:$4";
    $array_id{$mpath_id}=$sxm_arrays->{$2};
    $dm_id{$mpath_id}=$5;
    $mpath_to_ldev{$mpath_id}=$1;
  }
  if (m/^([0-9a-zA-Z]+)\_(\w{2})(\w{2}) (dm-\d*) HIT/)
  {
    $mpath_id="$1_$2$3";
    $ldev{"$1_$2$3"}="$2:$3"; 
    $array_id{"$1_$2$3"}=$1;
    $dm_id{"$1_$2$3"}=$4;
  }

  if ($RELEASE >= 6.0) {
    $lun_size{$mpath_id}=$1 if m/size=([0-9A-Z\.]+)/;
    #$sub_path{$mpath_id}.=$1 if m/^  \|- [\d,\:]+ *(\w+ )/;
    #$sub_path{$mpath_id}.=$1 if m/^  `- [\d,\:]+ *(\w+ )/;
    $sub_path{$mpath_id}.=$1 if m/^  [\|`]- [\d,\:]+ *(\w+ )/;
  }
  else
  {
    $lun_size{$mpath_id}=$1 if m/\[size=([0-9A-Z\.]+)\]/;
    $sub_path{$mpath_id}.=$1 if m/ \\\_ [\d,\:]+ *(\w+ )/;
  }

}
close MPATH;

%mpath_to_ldev=reverse %mpath_to_ldev;
if ($RELEASE >= 6.0) {
  open B,"ls -lL /dev/mapper|" or die "can't fork: $!";
}
else
{
  open B,"ls -lL /dev/mpath|" or die "can't fork: $!";
}
while (<B>) {
  chmop;
  $majmin{"$1,$2"}=$3 if m/^b.* (\d+), *(\d+) +\S+ +\S+ +\S+ +(\w+\_\w+)/;
  if(m/^b.* (\d+), *(\d+) +\S+ +\S+ +\S+ +(mpath\w+)p1/){
    $majmin{"$1,$2"}=$mpath_to_ldev{$3}."p1";
  }
  elsif (m/^b.* (\d+), *(\d+) +\S+ +\S+ +\S+ +(mpath\w+)/){
    $majmin{"$1,$2"}=$mpath_to_ldev{$3};
  }
}
close B;

# The following is independent of RHEL version
%rmajmin=reverse %majmin;
open C,"ls -l /dev/oracleasm/disks|" or die "can't fork: $!";
while (<C>) {
  chmop;
  $asmdev{"$1,$2"}=$3 if m/^b.* (\d+), *(\d+) +\S+ +\S+ +\S+ +(\S+)$/;
}
close C;
print (keys %sxm_arrays),"\n";

%mpath_to_ldev=reverse %mpath_to_ldev;
%$sxm_arrays=reverse %$sxm_arrays;
@sorted = sort { $asmdev{$a} cmp $asmdev{$b} } keys %asmdev;
format STDOUT=
@<<<<<<<<<<<<<<<<<<<<<@<<<<<<<<<<<<<<<<@<<<<<<<<<<<<<<<@<<<<<<<<@<<<<<<<<<<<<<@<<<<<<<@<<<<@<<<<<@<<<<<@<<<<<<<@*
$a,                   $dgname          $b,       $c,     $d,     $e,    $f,  $g,   $h,   $i,     $j
.
$_='ASM_DEV_NAME ASM_DG PATH DevID D-Path DM SER LDEV SIZE D-DevID SUBPATH';
($a,$dgname,$b,$c,$d,$e,$f,$g,$h,$i,$j)=split;
write (STDOUT);
foreach  (@sorted) {
  ($a,$b,$c)=($asmdev{$_},$majmin{$_},$_);
  $dgname=`dd if=/dev/oracleasm/disks/$a bs=8 skip=13 count=4 2>/dev/null|strings`;
  $_=$majmin{$_};m/([a-zA-Z0-9]+_\w{4})/;$_=$1;
  ($d,$e,$f,$g,$h,$i,$j)=($_,$dm_id{$_},$sxm_arrays->{$array_id{$_}},$ldev{$_},$lun_size{$_},$rmajmin{$_},$sub_path{$_});
  if (scalar(keys %mpath_to_ldev) != 0) {
    $d=$mpath_to_ldev{$d};
    $b=~m/(.*)p1$/;
    $b=$mpath_to_ldev{$1}."p1";
  }
  write (STDOUT);
}

RAW OUTPUT
===============

RHEL5 
ORION1_1014 dm-4 HITACHI,OPEN-V
[size=800G][features=0][hwhandler=0][rw]
\_ round-robin 0 [prio=1][active]
 \_ 3:0:1:27  sdac 65:192  [active][ready]
 \_ 4:0:1:27  sdcm 69:160  [active][ready]
 \_ 7:0:0:27  sdew 129:128 [active][ready]
 \_ 8:0:0:27  sdhg 133:96  [active][ready]

RHEL6
ORION1_3006 dm-2 HITACHI,OPEN-V
size=50G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  |- 2:0:0:0 sdc 8:32  active ready  running
  `- 0:0:0:0 sdj 8:144 active ready  running