Re: [Qemu-devel] [PATCH v3] block/vxhs: Add Veritas HyperScale VxHS block device support

[ashish mittal]

Hi Eric,

On Fri, Oct 28, 2016 at 7:44 AM, Eric Blake <address@hidden> wrote:
> On 10/28/2016 02:44 AM, Ashish Mittal wrote:
>> This patch adds support for a new block device type called "vxhs".
>> Source code for the qnio library that this code loads can be downloaded from:
>> https://github.com/MittalAshish/libqnio.git
>>
>> Sample command line using the JSON syntax:
>> ./qemu-system-x86_64 -name instance-00000008 -S -vnc 0.0.0.0:0 -k en-us
>> -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5
>> -msg timestamp=on
>> 'json:{"driver":"vxhs","vdisk_id":"{c3e9095a-a5ee-4dce-afeb-2a59fb387410}",
>> "server":{"host":"172.172.17.4","port":"9999"}}'
>
> Are the {} really part of vdisk_id?  That's not a usual portion of a
> UUID.  And it should probably be spelled vdisk-id.
>

The {} are not required for qemu/libqnio or the test server. It is
just some artifact that our openstack components need. Then test
server does not need {} at all. I will remove it from the sample
command syntax in v4.

> It's a shame that port is a string and not an int, but it matches
> existing practice, so that part is correct.
>
>>
>> Sample command line using the URI syntax:
>> qemu-img convert -f raw -O raw -n
>> /var/lib/nova/instances/_base/0c5eacd5ebea5ed914b6a3e7b18f1ce734c386ad
>> vxhs://192.168.0.1:9999/%7Bc6718f6b-0401-441d-a8c3-1f0064d75ee0%7D
>>
>
> The URI syntax is potentially harder to use when compared to structured
> usage (Kevin's work to add -blockdev, which depends on the QAPI definition).
>

We decided to keep both after discussion with other reviewers. Do
qemu-img and qemu-io binaries support json syntax similar to
qemu-system-x86_64?

>> Signed-off-by: Ashish Mittal <address@hidden>
>> ---
>> v3 changelog:
>> (1) Added QAPI schema for the VxHS driver.
>>
>
> For this email, I'm focusing just on the QAPI.
>
>> +++ b/qapi/block-core.json
>> @@ -1708,7 +1708,7 @@
>>  ##
>>  { 'enum': 'BlockdevDriver',
>>    'data': [ 'archipelago', 'blkdebug', 'blkverify', 'bochs', 'cloop',
>> -            'dmg', 'file', 'ftp', 'ftps', 'gluster', 'host_cdrom',
>> +            'dmg', 'file', 'ftp', 'ftps', 'gluster', 'host_cdrom', 'vxhs',
>>              'host_device', 'http', 'https', 'luks', 'null-aio', 'null-co',
>
> Missing mention of the new enum value in the comments above.
>

Will fix in v4.

>>              'parallels', 'qcow', 'qcow2', 'qed', 'quorum', 'raw',
>>           'replication', 'tftp', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat' ] }
>> @@ -2220,6 +2220,21 @@
>>    'data': { 'filename': 'str' } }
>>
>>  ##
>> +# @BlockdevOptionsVxHS
>> +#
>> +# Driver specific block device options for VxHS
>> +#
>> +# @vdisk_id:    UUID of VxHS volume
>
> Again, this should be vdisk-id.
>
Will fix in v4.

>> +#
>> +# @server:      vxhs server IP, port
>> +#
>> +# Since: 2.7
>
> You missed 2.7; this should be 2.8 (if you make soft freeze) or even 2.9.
>
Will fix in v4.

>> +##
>> +{ 'struct': 'BlockdevOptionsVxHS',
>> +  'data': { 'vdisk_id': 'str',
>> +            'server': 'InetSocketAddress' } }
>
> Is there any way to use a Unix socket, or is this server ONLY accessible
> over IPv4/IPv6?
>

Right now we support IPv4 only.

>
>> +
>> +##
>>  # @BlockdevOptions
>>  #
>>  # Options for creating a block device.  Many options are available for all
>> @@ -2283,7 +2298,8 @@
>>        'vhdx':       'BlockdevOptionsGenericFormat',
>>        'vmdk':       'BlockdevOptionsGenericCOWFormat',
>>        'vpc':        'BlockdevOptionsGenericFormat',
>> -      'vvfat':      'BlockdevOptionsVVFAT'
>> +      'vvfat':      'BlockdevOptionsVVFAT',
>> +      'vxhs':       'BlockdevOptionsVxHS'
>>    } }
>>
>>  ##
>>
>
> --
> Eric Blake   eblake redhat com    +1-919-301-3266
> Libvirt virtualization library http://libvirt.org
>