Add api to support change device vgpu_type

implement blueprint update-vgpu-type

Change-Id: I7c37f523b4228185ac0cb6acd906fa248ef88033

specs/2023.2/approved/change_vgpu_type_support.rst

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+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+=====================
+Support attribute API
+=====================
+
+This spec adds a new API to update the device vgpu_type.
+
+Problem description
+===================
+
+So far, we manage vgpu_type by configuring gpu_devices[1]_ and need configure
+the vgpu_type for every GPU. When we change the vgpu_type, we have to restart
+the cyborg-agent service. Which is complex and uneasy to change as more
+and more GPUs are required nowadays.
+In addition, when we change the vgpu_type configuration if the GPU has been
+allocated to VM, the GPU report task will raise exception.
+
+Use Cases
+---------
+
+1.An admin or operator wants to change the vgpu_type convenient.
+2.An admin or operator cannot change the vgpu_type if the GPU is using.
+
+Proposed change
+===============
+
+For the case 1, we can provider an API to change the vgpu_type for the single
+GPU, and call the cyborg-agent the period task to report the new info, making
+the vgpu_type effective immediately.
+For the case 2, we can check the GPU usage state before change its vgpu_type,
+if the GPU is using, we forbidden to change the vgpu_type.
+
+Alternatives
+------------
+
+None
+
+Data model impact
+-----------------
+
+* Add new column `vgpu_type` for the devices table. The column is StringField
+type and store the vgpu_type info like `{'vgpu_type': 'nvidia-180'}`.
+
+REST API impact
+---------------
+
+URL: ``/v2/devices/{uuid}``
+
+METHOD: ``PATCH``
+
+    Update vgpu_type for the device.
+
+Request body::
+
+{
+  "vgpu_type": "nvidia-181"
+}
+
+Normal response code (200) and body::
+
+* 204 (No content)
+
+* No response body
+
+
+Error response code and body:
+
+* 401 (Unauthorized): Unauthorized
+
+* 403 (Forbidden): RBAC check failed
+
+* No response body
+
+
+Security impact
+---------------
+None
+
+Notifications impact
+--------------------
+None
+
+Other end user impact
+---------------------
+* Change Cyborg Device table.
+
+
+Performance Impact
+------------------
+None
+
+Other deployer impact
+---------------------
+No need to configure the vpgu_type for cyborg-agent.
+
+Developer impact
+----------------
+If the user want to use these feature, they should upgrade their Cyborg
+project to latest to support these changes.
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+Primary assignee:
+  songwenping
+
+Work Items
+----------
+
+* Change Cyborg Device table.
+* Add API of patching vgpu_type for the device.
+* Change cyborgclient to support change vgpu_type action.
+* Add related tests.
+
+Dependencies
+============
+None
+
+Testing
+=======
+Appropriate unit and functional tests should be added.
+
+Documentation Impact
+====================
+* Need a documentation to record microversion history.
+* Need a documentaiton to explain api usage.
+
+References
+==========
+.. [1] https://specs.openstack.org/openstack/cyborg-specs/specs/2023.1/implemented/vgpu-driver-proposal.html
+
+History
+=======
+.. list-table:: Revisions
+   :header-rows: 1
+
+   * - Release Name
+     - Description
+   * - Bobcat
+     - Introduced