doc: add JSON-RPC docs for nvmf_tgt methods

This is a first pass at adding documentation for JSON-RPC methods.

Currently, this covers the following nvmf_tgt RPC methods:
- get_nvmf_subsystems
- construct_nvmf_subsystem
- delete_nvmf_subsystem

Change-Id: I51f74eed52e68fef8307a278b2e36c326689bf92
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-on: https://review.gerrithub.io/381559
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

doc/Doxyfile

@@ -793,6 +793,7 @@ INPUT                  = ../include/spdk \
                          event.md \
                          ioat.md \
                          iscsi.md \
+                         jsonrpc.md \
                          lvol.md \
                          nvme.md \
                          nvme-cli.md \

doc/index.md

@@ -18,6 +18,7 @@
  - @ref memory
  - @ref porting
  - [Public API header files](files.html)
+ - @ref jsonrpc
 
 # Modules {#modules}
 

doc/jsonrpc.md

@@ -0,0 +1,176 @@
+# JSON-RPC Methods {#jsonrpc}
+
+# Overview {#jsonrpc_overview}
+
+SPDK implements a [JSON-RPC 2.0](http://www.jsonrpc.org/specification) server
+to allow external management tools to dynamically configure SPDK components.
+
+# NVMe-oF Target {#jsonrpc_components_nvmf_tgt}
+
+## get_nvmf_subsystems method {#rpc_get_nvmf_subsystems}
+
+### Parameters
+
+This method has no parameters.
+
+### Example
+
+Example request:
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "get_nvmf_subsystems"
+}
+~~~
+
+Example response:
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "result": [
+    {
+      "core": 0,
+      "nqn": "nqn.2014-08.org.nvmexpress.discovery",
+      "subtype": "Discovery"
+      "listen_addresses": [],
+      "hosts": [],
+      "allow_any_host": true
+    },
+    {
+      "core": 5,
+      "nqn": "nqn.2016-06.io.spdk:cnode1",
+      "subtype": "NVMe",
+      "listen_addresses": [
+        {
+          "trtype": "RDMA",
+          "adrfam": "IPv4",
+          "traddr": "192.168.0.123",
+          "trsvcid": "4420"
+        }
+      ],
+      "hosts": [
+        {"nqn": "nqn.2016-06.io.spdk:host1"}
+      ],
+      "allow_any_host": false,
+      "serial_number": "abcdef",
+      "namespaces": [
+        {"nsid": 1, "name": "Malloc2"},
+        {"nsid": 2, "name": "Nvme0n1"}
+      ]
+    }
+  ]
+}
+~~~
+
+## construct_nvmf_subsystem method {#rpc_construct_nvmf_subsystem}
+
+Construct an NVMe over Fabrics target subsystem.
+
+### Parameters
+
+Name                    | Optional | Type        | Description
+----------------------- | -------- | ----------- | -----------
+core                    | Optional | number      | Core to run the subsystem's poller on. Default: Automatically assign a core.
+nqn                     | Required | string      | Subsystem NQN
+listen_addresses        | Required | array       | Array of @ref rpc_construct_nvmf_subsystem_listen_address objects
+hosts                   | Optional | array       | Array of strings containing allowed host NQNs. Default: No hosts allowed.
+allow_any_host          | Optional | boolean     | Allow any host (`true`) or enforce allowed host whitelist (`false`). Default: `false`.
+serial_number           | Required | string      | Serial number of virtual controller
+namespaces              | Optional | array       | Array of @ref rpc_construct_nvmf_subsystem_namespace objects. Default: No namespaces.
+
+### listen_address {#rpc_construct_nvmf_subsystem_listen_address}
+
+Name                    | Optional | Type        | Description
+----------------------- | -------- | ----------- | -----------
+trtype                  | Required | string      | Transport type ("RDMA")
+adrfam                  | Required | string      | Address family ("IPv4", "IPv6", "IB", or "FC")
+traddr                  | Required | string      | Transport address
+trsvcid                 | Required | string      | Transport service ID
+
+### namespace {#rpc_construct_nvmf_subsystem_namespace}
+
+Name                    | Optional | Type        | Description
+----------------------- | -------- | ----------- | -----------
+nsid                    | Optional | number      | Namespace ID between 1 and 4294967294, inclusive. Default: Automatically assign NSID.
+bdev_name               | Required | string      | Name of bdev to expose as a namespace.
+
+### Example
+
+Example request:
+
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "construct_nvmf_subsystem",
+  "params": {
+    "core": 5,
+    "nqn": "nqn.2016-06.io.spdk:cnode1",
+    "listen_addresses": [
+      {
+        "trtype": "RDMA",
+        "adrfam": "IPv4",
+        "traddr": "192.168.0.123",
+        "trsvcid: "4420"
+      }
+    ],
+    "hosts": [
+      "nqn.2016-06.io.spdk:host1",
+      "nqn.2016-06.io.spdk:host2"
+    ],
+    "allow_any_host": false,
+    "serial_number": "abcdef",
+    "namespaces": [
+      {"nsid": 1, "name": "Malloc2"},
+      {"nsid": 2, "name": "Nvme0n1"}
+    ]
+  }
+}
+~~~
+
+Example response:
+
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "result": true
+}
+~~~
+
+## delete_nvmf_subsystem method {#rpc_delete_nvmf_subsystem}
+
+Delete an existing NVMe-oF subsystem.
+
+### Parameters
+
+Parameter              | Optional | Type        | Description
+---------------------- | -------- | ----------- | -----------
+nqn                    | Required | string      | Subsystem NQN to delete.
+
+### Example
+
+Example request:
+
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "method": "delete_nvmf_subsystem",
+  "params": {
+    "nqn": "nqn.2016-06.io.spdk:cnode1"
+  }
+}
+~~~
+
+Example response:
+
+~~~
+{
+  "jsonrpc": "2.0",
+  "id": 1,
+  "result": true
+}
+~~~