Merge pull request #73 from elezar/add-host-path

Add HostPath to DeviceNode to allow for use cases where device nodes are not at root

Author: bart0sh

README.md

@@ -71,14 +71,14 @@ Remember to restart containerd for any configuration changes to take effect.
 $ mkdir /etc/cdi
 $ cat > /etc/cdi/vendor.json <<EOF
 {
-  "cdiVersion": "0.4.0",
+  "cdiVersion": "0.5.0",
   "kind": "vendor.com/device",
   "devices": [
     {
       "name": "myDevice",
       "containerEdits": {
         "deviceNodes": [
-          {"path": "/dev/card1", "type": "c", "major": 25, "minor": 25, "fileMode": 384, "permissions": "rw", "uid": 1000, "gid": 1000},
+          {"hostPath": "/vendor/dev/card1": "path": "/dev/card1", "type": "c", "major": 25, "minor": 25, "fileMode": 384, "permissions": "rw", "uid": 1000, "gid": 1000},
           {"path": "/dev/card-render1", "type": "c", "major": 25, "minor": 25, "fileMode": 384, "permissions": "rwm", "uid": 1000, "gid": 1000}
         ]
       }

SPEC.md

@@ -8,7 +8,7 @@
 
 ## Version
 
-This is CDI **spec** version **0.4.0**.
+This is CDI **spec** version **0.5.0**.
 
 ### Update policy
 
@@ -25,6 +25,7 @@ Released versions of the spec are available as Git tags.
 | -----| -----------------| -------|
 | v0.3.0 |   | Initial tagged release of Spec |
 | v0.4.0 |   | Added `type` field to Mount specification |
+| v0.5.0 |   | Add `HostPath` to `DeviceNodes` |
 
 *Note*: The initial release of a **spec** with version `v0.x.0` will be tagged as
 `v0.x.0` with subsequent changes to the API applicable to this version tagged as `v0.x.y`.
@@ -79,7 +80,7 @@ The key words "must", "must not", "required", "shall", "shall not", "should", "s
 
 ```
 {
-    "cdiVersion": "0.3.0",
+    "cdiVersion": "0.5.0",
     "kind": "<name>",
 
     "devices": [
@@ -103,6 +104,7 @@ The key words "must", "must not", "required", "shall", "shall not", "should", "s
             "deviceNodes": [ (optional)
                 {
                     "path": "<path>",
+                    "hostPath": "<hostPath>" (optional),
                     "type": "<type>" (optional),
                     "major": <int32> (optional),
                     "minor": <int32> (optional),
@@ -181,6 +183,7 @@ The `containerEdits` field has the following definition:
   * `env` (array of strings in the format of "VARNAME=VARVALUE", OPTIONAL) describes the environment variables that should be set. These values are appended to the container environment array.
   * `deviceNodes` (array of objects, OPTIONAL) describes the device nodes that should be mounted:
     * `path` (string, REQUIRED) path of the device within the container.
+    * `hostPath` (string, OPTIONAL) path of the device node on the host. If not specified the value for `path` is used.
     * `type` (string, OPTIONAL) Device type: block, char, etc.
     * `major` (int64, OPTIONAL) Device major number.
     * `minor` (int64, OPTIONAL) Device minor number.

pkg/cdi/container-edits.go

@@ -85,11 +85,13 @@ func (e *ContainerEdits) Apply(spec *oci.Spec) error {
 	}
 
 	for _, d := range e.DeviceNodes {
-		dev := d.ToOCI()
-		if err := fillMissingInfo(&dev); err != nil {
+		dn := DeviceNode{d}
+
+		err := dn.fillMissingInfo()
+		if err != nil {
 			return err
 		}
-
+		dev := d.ToOCI()
 		if dev.UID == nil && spec.Process != nil {
 			if uid := spec.Process.User.UID; uid > 0 {
 				dev.UID = &uid
@@ -288,26 +290,31 @@ func ensureOCIHooks(spec *oci.Spec) {
 }
 
 // fillMissingInfo fills in missing mandatory attributes from the host device.
-func fillMissingInfo(dev *oci.LinuxDevice) error {
-	if dev.Type != "" && (dev.Major != 0 || dev.Type == "p") {
+func (d *DeviceNode) fillMissingInfo() error {
+	if d.HostPath == "" {
+		d.HostPath = d.Path
+	}
+
+	if d.Type != "" && (d.Major != 0 || d.Type == "p") {
 		return nil
 	}
-	hostDev, err := runc.DeviceFromPath(dev.Path, "rwm")
+
+	hostDev, err := runc.DeviceFromPath(d.HostPath, "rwm")
 	if err != nil {
-		return errors.Wrapf(err, "failed to stat CDI host device %q", dev.Path)
+		return errors.Wrapf(err, "failed to stat CDI host device %q", d.HostPath)
 	}
 
-	if dev.Type == "" {
-		dev.Type = string(hostDev.Type)
+	if d.Type == "" {
+		d.Type = string(hostDev.Type)
 	} else {
-		if dev.Type != string(hostDev.Type) {
-			return errors.Errorf("CDI device %q, host type mismatch (%s, %s)",
-				dev.Path, dev.Type, string(hostDev.Type))
+		if d.Type != string(hostDev.Type) {
+			return errors.Errorf("CDI device (%q, %q), host type mismatch (%s, %s)",
+				d.Path, d.HostPath, d.Type, string(hostDev.Type))
 		}
 	}
-	if dev.Major == 0 && dev.Type != "p" {
-		dev.Major = hostDev.Major
-		dev.Minor = hostDev.Minor
+	if d.Major == 0 && d.Type != "p" {
+		d.Major = hostDev.Major
+		d.Minor = hostDev.Minor
 	}
 
 	return nil

pkg/cdi/spec.go

@@ -36,6 +36,7 @@ var (
 		"0.2.0": {},
 		"0.3.0": {},
 		"0.4.0": {},
+		"0.5.0": {},
 	}
 
 	// Externally set CDI Spec validation function.

schema/defs.json

@@ -29,6 +29,9 @@
                 "path": {
                     "$ref": "#/definitions/FilePath"
                 },
+                "hostPath": {
+                    "$ref": "#/definitions/FilePath"
+                },
                 "permissions": {
                     "type": "string"
                 },

schema/testdata/good/spec-example.json

@@ -1,12 +1,12 @@
 {
-  "cdiVersion": "0.4.0",
+  "cdiVersion": "0.5.0",
   "kind": "vendor.com/device",
   "devices": [
     {
       "name": "myDevice",
       "containerEdits": {
         "deviceNodes": [
-          {"path": "/dev/card1"},
+          {"hostPath": "/vendorroot/dev/card1", "path": "/dev/card1"},
           {"path": "/dev/card2"}
         ]
       }

specs-go/config.go

@@ -3,7 +3,7 @@ package specs
 import "os"
 
 // CurrentVersion is the current version of the Spec.
-const CurrentVersion = "0.4.0"
+const CurrentVersion = "0.5.0"
 
 // Spec is the base configuration for CDI
 type Spec struct {
@@ -31,6 +31,7 @@ type ContainerEdits struct {
 // DeviceNode represents a device node that needs to be added to the OCI spec.
 type DeviceNode struct {
 	Path        string       `json:"path"`
+	HostPath    string       `json:"hostPath,omitempty"`
 	Type        string       `json:"type,omitempty"`
 	Major       int64        `json:"major,omitempty"`
 	Minor       int64        `json:"minor,omitempty"`