Also no ifs, buts, or whiles

#! perl -slw
use strict;
use Data::Dumper;

my %hash = map{
    my( $free, $name, $size ) = m[
        ^
        (?= .* FreeSpace \s+ = \s+ " ( [^"]+ ) "; ) #"
        (?= .* Name      \s+ = \s+ " ( [^"]+ ) "; ) #"
        (?= .* Size      \s+ = \s+ " ( [^"]+ ) "; ) #"
    ]smx or warn "Bad record '$_'";
    $name ? ( $name => { freespace => $free, size => $size } ) : ();
} do{ local $/ = "\n};\n"; <DATA> };

print Dumper \%hash;

__DATA__
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Given your data, produces this

P:\test>junk
$VAR1 = {
          'C:' => {
                    'freespace' => '114151464960',
                    'size' => '160031014912'
                  },
          'D:' => {
                    'freespace' => '5515554816',
                    'size' => '203921108992'
                  },
          'H:' => {
                    'freespace' => '43128733696',
                    'size' => '400086708224'
                  }
        };
[download]