Add doc for Huawei driver

Add doc for Huawei driver with descriptions on its requirements,
limitations, and configuration instructions.

Change-Id: I212ddf9f0b4b50d62970043405ea3cb59b83f03b

doc/source/devref/huawei_nas_driver.rst

@@ -0,0 +1,109 @@
+..
+      Copyright (c) 2015 Huawei Technologies Co., Ltd.
+      All Rights Reserved.
+
+      Licensed under the Apache License, Version 2.0 (the "License"); you may
+      not use this file except in compliance with the License. You may obtain
+      a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+      Unless required by applicable law or agreed to in writing, software
+      distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+      WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+      License for the specific language governing permissions and limitations
+      under the License.
+
+Huawei Driver
+=============
+
+Huawei NAS Driver is a plugin based the OpenStack Manila service. The Huawei NAS
+Driver can be used to provide functions such as the share and snapshot for virtual
+machines(instances) in OpenStack. Huawei NAS Driver enables the OceanStor V3 series
+V300R002 storage system to provide only network filesystems for OpenStack.
+
+Requirements
+------------
+
+- The OceanStor V3 series V300R002 storage system.
+- The following licenses should be activated on V3 for File:
+  * CIFS
+  * NFS
+  * HyperSnap License (for snapshot)
+
+Supported Operations
+--------------------
+
+The following operations is supported on V3 storage:
+
+- Create CIFS/NFS Share
+- Delete CIFS/NFS Share
+- Allow CIFS/NFS Share access
+  * Only IP access type is supported for NFS.
+  * Only USER access type is supported for CIFS.
+- Deny CIFS/NFS Share access
+- Create snapshot
+- Delete snapshot
+
+Pre-Configurations on Huawei
+----------------------------
+
+1. Create a driver configuration file. The driver configuration file name must
+be the same as the manila_huawei_conf_file item in the manila_conf configuration
+file.
+
+2. Configure Product.
+Product indicates the storage system type. For the OceanStor V3 series V300R002
+storage systems, the driver configuration file is as follows:
+
+::
+
+    <?xml version='1.0' encoding='UTF-8'?>
+    <Config>
+        <Storage>
+            <Product>V3</Product>
+            <LogicalPortIP>x.x.x.x</LogicalPortIP>
+            <RestURL>https://x.x.x.x:8088/deviceManager/rest/</RestURL>
+            <UserName>xxxxxxxxx</UserName>
+            <UserPassword>xxxxxxxxx</UserPassword>
+        </Storage>
+        <Filesystem>
+            <AllocType>Thin</AllocType>
+            <StoragePool>xxxxxxxxx</StoragePool>
+            <WaitInterval>3</WaitInterval>
+            <Timeout>60</Timeout>
+        </Filesystem>
+    </Config>
+
+- `Product` is a type of a storage product. Set it to `V3`.
+- `LogicalPortIP` is a IP address of the logical port.
+- `RestURL` is a access address of the REST interface.
+- `UserName` is a user name of an administrator.
+- `UserPassword` is a password of an administrator.
+- `AllocType` is a type of file system space allocation. Valid values are
+  Thick or Thin.
+- `StoragePool` is a name of a storage pool to be used.
+- `WaitInterval` is the interval time of querying the file system status.
+- `Timeout` is the timeout period for wating command execution of a device to
+  complete.
+
+Backend Configuration
+---------------------
+
+1. Modify the `manila.conf` Manila configuration file and add share_driver and
+manila_huawei_conf_file items.
+Example for configuring a storage system:
+
+    share_driver = manila.share.drivers.huawei.huawei_nas.HuaweiNasDriver
+    manila_huawei_conf_file = /etc/manila/manila_huawei_conf.xml
+
+Restrictions
+------------
+
+The Huawei driver has the following restrictions:
+
+- Only IP access type is supported for NFS.
+
+- Only USER access type is supported for CIFS.
+
+- Only one StoragePool can be configured in the configuration file.

doc/source/devref/index.rst

@@ -80,6 +80,7 @@ Share backends
    cluster_mode_driver
    emc_vnx_driver
    generic_driver
+   huawei_nas_driver
 
 Indices and tables
 ------------------