Re: [Kimchi-devel] [PATCH v4 2/2] logical pool: list unused physical volume

Physical volume belongs to no volume group can be considered a free block device to use. Implement a _get_vgname() function to get volume group name of a device node. If the requested block device is not a physical volume, it returns empty string, otherwise returns volume group name. Then it inspects the volume group name for all potential devices and filters out in use physical volumes. Signed-off-by: Zhou Zheng Sheng <zhshzhou(a)linux.vnet.ibm.com&gt; --- src/kimchi/disks.py | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/src/kimchi/disks.py b/src/kimchi/disks.py index a7e5616..941aaca 100644 --- a/src/kimchi/disks.py +++ b/src/kimchi/disks.py @@ -99,6 +99,20 @@ def _parse_lsblk_output(output, keys): return r +def _get_vgname(devNodePath): + """ Return volume group name of a physical volume. If the device node path + is not a physical volume, return empty string. """ + pvs = subprocess.Popen( + ["pvs", "--unbuffered", "--nameprefixes", "--noheadings", + "-o", "vg_name", devNodePath], + stdout=subprocess.PIPE, stderr=subprocess.PIPE) + out, err = pvs.communicate() + if pvs.returncode != 0: + return "" + + return re.findall(r"LVM2_VG_NAME='([^\']*)'", out)[0] + + def get_partitions_names(): names = [] keys = ["NAME", "TYPE", "FSTYPE", "MOUNTPOINT", "MAJ:MIN"] @@ -111,10 +125,12 @@ def get_partitions_names(): devNodePath = _get_dev_node_path(dev['maj:min']) # Only list unmounted and unformated and leaf and (partition or disk) # leaf means a partition, a disk has no partition, or a disk not held - # by any multipath device. + # by any multipath device. Physical volume belongs to no volume group + # is also listed. if not (dev['type'] in ['part', 'disk'] and - dev['fstype'] == "" and + dev['fstype'] in ['', 'LVM2_member'] and dev['mountpoint'] == "" and + _get_vgname(devNodePath) == "" and _is_dev_leaf(devNodePath)): continue