Rewrite LinuxIDMappings

Basicly make the format consistent with others, no
semantics change.

Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>

Author: hqhq

config-linux.md

@@ -73,6 +73,18 @@ If a new namespace is not created (because the namespace type is not listed, or
 
 ## User namespace mappings
 
+**`uidMappings`** (array of objects, OPTIONAL) describes the user namespace uid mappings from the host to the container.
+**`gidMappings`** (array of objects, OPTIONAL) describes the user namespace gid mappings from the host to the container.
+
+The following parameters can be specified:
+
+* **`hostID`** (uint32, REQUIRED)* - is the starting uid/gid on the host to be mapped to *containerID*.
+* **`containerID`** (uint32, REQUIRED)* - is the starting uid/gid in the container.
+* **`size`** (uint32, REQUIRED)* - is the number of ids to be mapped.
+
+The runtime SHOULD NOT modify the ownership of referenced filesystems to realize the mapping.
+There is a limit of 5 mappings which is the Linux kernel hard limit.
+
 ###### Example
 
 ```json
@@ -92,11 +104,6 @@ If a new namespace is not created (because the namespace type is not listed, or
     ]
 ```
 
-uid/gid mappings describe the user namespace mappings from the host to the container.
-The runtime SHOULD NOT modify the ownership of referenced filesystems to realize the mapping.
-*hostID* is the starting uid/gid on the host to be mapped to *containerID* which is the starting uid/gid in the container and *size* refers to the number of ids to be mapped.
-There is a limit of 5 mappings which is the Linux kernel hard limit.
-
 ## Devices
 
 **`devices`** (array of objects, OPTIONAL) lists devices that MUST be available in the container.

specs-go/config.go

@@ -187,11 +187,11 @@ const (
 
 // LinuxIDMapping specifies UID/GID mappings
 type LinuxIDMapping struct {
-	// HostID is the UID/GID of the host user or group
+	// HostID is the starting UID/GID on the host to be mapped to 'ContainerID'
 	HostID uint32 `json:"hostID"`
-	// ContainerID is the UID/GID of the container's user or group
+	// ContainerID is the starting UID/GID in the container
 	ContainerID uint32 `json:"containerID"`
-	// Size is the length of the range of IDs mapped between the two namespaces
+	// Size is the number of IDs to be mapped
 	Size uint32 `json:"size"`
 }