[Kimchi-devel] [PATCH] Logical Storage Pool: Detect and Enumerate Multipath Block Devices

[Aline Manera]

On 03/25/2014 04:56 AM, Zhou Zheng Sheng wrote:
> Thanks a lot for the comments on the back-end code. I will change it in
> v2. Maybe Hong Liang can share what he thinks on the front-end code.
> Then I'll update the patch.
>
> on 2014/03/25 14:15, Mark Wu wrote:
>> On 03/25/2014 11:52 AM, zhshzhou at linux.vnet.ibm.com wrote:
>>> From: Zhou Zheng Sheng <zhshzhou at linux.vnet.ibm.com>
>>>
>>> When creating a logical storage pool Kimci ignores multipath block
>>> devices. This is on purpose because at the time the kimchi.disks was
>>> implemented, there was not enough time to test every kind of devices.
>>>
>>> This patch adds the missing support for multipath block devices. After
>>> this patch, the kimchi.disks will include multipath devices in the
>>> available partition list. The front-end code is also changed
>>> accordingly.
>>>
>>> Signed-off-by: Zhou Zheng Sheng <zhshzhou at linux.vnet.ibm.com>
>>> ---
>>>    src/kimchi/disks.py                      | 20 +++++++++++++++++++-
>>>    ui/js/src/kimchi.storagepool_add_main.js |  3 ++-
>>>    2 files changed, 21 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/src/kimchi/disks.py b/src/kimchi/disks.py
>>> index ce0c5bb..6817ab4 100644
>>> --- a/src/kimchi/disks.py
>>> +++ b/src/kimchi/disks.py
>>> @@ -17,6 +17,7 @@
>>>    # License along with this library; if not, write to the Free Software
>>>    # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>>> 02110-1301 USA
>>>
>>> +import errno
>>>    import re
>>>    import subprocess
>>>
>>> @@ -27,8 +28,25 @@ from kimchi.exception import OperationFailed
>>>    from kimchi.utils import kimchi_log
>>>
>>>
>>> +def _get_friendly_dm_path(maj_min):
>>> +    """ Returns user friendly dm path given the device number
>>> 'major:min' """
>>> +    dm_name = "/sys/dev/block/%s/dm/name" % maj_min
>>> +    try:
>>> +        with open(dm_name) as dm_f:
>>> +            content = dm_f.read().rstrip('\n')
>>> +    except IOError as e:
>>> +        if not e.errno == errno.ENOENT:
>> why not "!="
>>> +            raise
>>> +        return None
>>> +    return "/dev/mapper/" + content
>>> +
>>> +
>>>    def _get_dev_node_path(maj_min):
>>>        """ Returns device node path given the device number 'major:min' ""
>>> +    dm_path = _get_friendly_dm_path(maj_min)
>> check if string starts with "253:"  could avoid reading the dm name file
>> for non device mapper file.
>> The major device number 253 is reserved for device mapper device in
>> kernel.  It's reliable.
>>> +    if dm_path is not None:
>>> +        return dm_path
>>> +
>>>        uevent = "/sys/dev/block/%s/uevent" % maj_min
>>>        with open(uevent) as ueventf:
>>>            content = ueventf.read()
>>> @@ -137,7 +155,7 @@ def get_partitions_names():
>>>            # leaf means a partition, a disk has no partition, or a disk
>>> not held
>>>            # by any multipath device. Physical volume belongs to no
>>> volume group
>>>            # is also listed. Extended partitions should not be listed.
>>> -        if not (dev['type'] in ['part', 'disk'] and
>>> +        if not (dev['type'] in ['part', 'disk', 'mpath'] and
>>>                    dev['fstype'] in ['', 'LVM2_member'] and
>>>                    dev['mountpoint'] == "" and
>>>                    _get_vgname(devNodePath) == "" and
>>> diff --git a/ui/js/src/kimchi.storagepool_add_main.js
>>> b/ui/js/src/kimchi.storagepool_add_main.js
>>> index 10833be..f3b85d2 100644
>>> --- a/ui/js/src/kimchi.storagepool_add_main.js
>>> +++ b/ui/js/src/kimchi.storagepool_add_main.js
>>> @@ -28,7 +28,8 @@ kimchi.initStorageAddPage = function() {
>>>                var deviceHtml = $('#partitionTmpl').html();
>>>                var listHtml = '';
>>>                $.each(data, function(index, value) {
>>> -                if (value.type === 'part' || value.type === 'disk') {
>>> +                valid_types = {part: 'part', disk: 'disk', mpath:
>>> 'mpath'};
>> what we need is just a list,  not sure if we can have a 'in' operation
>> for list in js.   Maybe Hongliang can help here.


According to Adam we can do:

list = ['part', 'disk', 'mpath']
if list.indexOf(value.type) != -1 {
     ....
}

>>> +                if (value.type in valid_types) {
>>>                        listHtml += kimchi.template(deviceHtml, value);
>>>                    }
>>>                });
>