Description of problem:
In a disk pool, when try to create a volume on a disk on which no primary partition is available, virsh vol-create command will fail.

Version-Release number of selected component (if applicable):
libvirt-0.8.1-8.el6.x86_64
# uname -a
Linux dhcp-66-70-6.nay.redhat.com 2.6.32-33.el6.x86_64 #1 SMP Thu Jun 3 13:00:03 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux


How reproducible:
Always

Steps to Reproduce:
1. Prepare a disk pool xml:
# cat pool-disk-test.xml 
<pool type='disk'>
  <name>sda</name>
  <source>
    <device path='/dev/sda'>
    </device>
  </source>
  <target>
    <path>/dev</path>
  </target>
</pool>

2. define the disk pool
# virsh pool-define pool-disk-test.xml 
Pool sda defined from pool-disk-test.xml

3. Start the pool
# virsh pool-start sda
Pool sda started

4. Check the current disk info:
# virsh pool-dumpxml sda
<pool type='disk'>
  <name>sda</name>
  <uuid>b0f38663-5d3f-1dd6-36eb-0fb86e7314a6</uuid>
  <capacity>500105249280</capacity>
  <allocation>200219604480</allocation>
  <available>299885483520</available>
  <source>
    <device path='/dev/sda'>
    <freeExtent start='58185630720' end='71707991040'/>
    <freeExtent start='213742126080' end='500105249280'/>
    </device>
    <format type='unknown'/>
  </source>
  <target>
    <path>/dev</path>
    <permissions>
      <mode>0700</mode>
      <owner>-1</owner>
      <group>-1</group>
    </permissions>
  </target>
</pool>


# parted
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print                                                            
Model: ATA Hitachi HDT72105 (scsi)
Disk /dev/sda: 500GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End     Size    Type      File system     Flags
 1      32.3kB  36.7GB  36.7GB  primary   ext3
 2      36.7GB  58.2GB  21.5GB  primary   ext3
 3      71.7GB  107GB   35.0GB  primary   ext3            boot
 4      107GB   500GB   393GB   extended
 5      107GB   109GB   2007MB  logical   linux-swap(v1)
 6      109GB   144GB   35.0GB  logical   ext3
 7      144GB   179GB   35.0GB  logical   ext3
 8      179GB   214GB   35.0GB  logical


(Note: There is no primary partition available, but there is still free space on this disk)


4. Try to create a vol in the pool
# cat vol-partition-test.xml 
<volume>
  <name>sda9</name>
  <key>/dev/sda9</key>
  <source>
    <device path='/dev/sda'>
    </device>
  </source>
  <capacity unit='M'>100</capacity>
  <target>
    <path>/dev/sda9</path>
  </target>
</volume>

# virsh vol-create sda vol-partition-test.xml 
error: Failed to create vol from vol-partition-test.xml
error: internal error '/sbin/parted /dev/sda mkpart --script primary 58185630720B 58290488319B' exited with non-zero status 1 and signal 0: /sbin/parted: invalid token: primary

  
Actual results:
virsh vol-create command always try to create a primary partition.

I try to specify "logical" format for the partition in xml, but looks like the command can not recognize "logical".
...
  <target>
    <path>/dev/sda9</path>
    <format type='logical'/>
  </target>
...

# virsh vol-create sda vol-partition-test.xml 
error: Failed to create vol from vol-partition-test.xml
error: XML description for unknown volume format type logical is not well formed or invalid


Expected results:
User should be successful to create logical partition on the disk where no primary partition is available.

Additional info: