WIP Support nfs local volume mounts

cmd/podman/volume_create.go

@@ -25,8 +25,8 @@ var (
 			return volumeCreateCmd(&volumeCreateCommand)
 		},
 		Example: `podman volume create myvol
-  podman volume create
-  podman volume create --label foo=bar myvol`,
+  podman volume create --label foo=bar
+  podman volume create --opt type=nfs --opt o=addr=192.168.0.2,rw --opt device=:/nfsshare  mynfsvol`,
 	}
 )
 

docs/podman-volume-create.1.md

@@ -29,7 +29,13 @@ Set metadata for a volume (e.g., --label mykey=value).
 
 **-o**, **--opt**=[]
 
-Set driver specific options.
+Set driver specific options. To setup NFS volume you need to specify:
+
+    type: `-o type=nfs` To indicate the nfs mount.
+
+    o: `-o o=addr=nfsserver.example.com,rw` Options including the address of the nfs server.
+
+    device: `-o device=/nfsshare`, the remote nfs share.
 
 ## EXAMPLES
 
@@ -39,6 +45,8 @@ $ podman volume create myvol
 $ podman volume create
 
 $ podman volume create --label foo=bar myvol
+
+# podman volume create --opt type=nfs --opt o=addr=192.168.0.2,rw --opt device=/nfsshare  mynfsvol
 ```
 
 ## SEE ALSO

libpod/runtime_ctr.go

@@ -191,6 +191,13 @@ func (r *Runtime) newContainer(ctx context.Context, rSpec *spec.Spec, options ..
 			return nil, errors.Wrapf(err, "error creating named volume %q", vol.Name)
 		}
 
+		options := newVol.Options()
+		if len(options) > 0 {
+			if err := newVol.Mount(); err != nil {
+				return nil, err
+			}
+		}
+
 		if err := ctr.copyWithTarFromImage(vol.Dest, newVol.MountPoint()); err != nil && !os.IsNotExist(err) {
 			return nil, errors.Wrapf(err, "Failed to copy content into new volume mount %q", vol.Name)
 		}

libpod/volume.go

@@ -1,5 +1,13 @@
 package libpod
 
+import (
+	"net"
+	"strings"
+
+	"github.com/containers/storage/pkg/mount"
+	"github.com/pkg/errors"
+)
+
 // Volume is the type used to create named volumes
 // TODO: all volumes should be created using this and the Volume API
 type Volume struct {
@@ -70,3 +78,57 @@ func (v *Volume) Scope() string {
 func (v *Volume) IsCtrSpecific() bool {
 	return v.config.IsCtrSpecific
 }
+
+// Mount the volume
+func (v *Volume) Mount() error {
+	if v.MountPoint() == "" {
+		return errors.Errorf("missing device in volume options")
+	}
+	mounted, err := mount.Mounted(v.MountPoint())
+	if err != nil {
+		return errors.Wrapf(err, "failed to determine if %v is mounted", v.Name())
+	}
+	if mounted {
+		return nil
+	}
+	options := v.Options()
+	if len(options) == 0 {
+		return errors.Errorf("volume %v is not mountable, no options available", v.Name())
+	}
+	mountOpts := options["o"]
+	device := options["device"]
+	if options["type"] == "nfs" {
+		if addrValue := getAddress(mountOpts); addrValue != "" && net.ParseIP(addrValue).To4() == nil {
+			ipAddr, err := net.ResolveIPAddr("ip", addrValue)
+			if err != nil {
+				return errors.Wrapf(err, "error resolving passed in nfs address")
+			}
+			mountOpts = strings.Replace(mountOpts, "addr="+addrValue, "addr="+ipAddr.String(), 1)
+		}
+		if device[0] != ':' {
+			device = ":" + device
+		}
+	}
+	err = mount.Mount(device, v.MountPoint(), options["type"], mountOpts)
+	return errors.Wrap(err, "failed to mount local volume")
+}
+
+// Unmount the volume from the system
+func (v *Volume) Unmount() error {
+	if v.MountPoint() == "" {
+		return errors.Errorf("missing device in volume options")
+	}
+	return mount.Unmount(v.MountPoint())
+}
+
+// getAddress finds out address/hostname from options
+func getAddress(opts string) string {
+	optsList := strings.Split(opts, ",")
+	for i := 0; i < len(optsList); i++ {
+		if strings.HasPrefix(optsList[i], "addr=") {
+			addr := strings.SplitN(optsList[i], "=", 2)[1]
+			return addr
+		}
+	}
+	return ""
+}

libpod/volume_internal.go

@@ -18,5 +18,6 @@ func newVolume(runtime *Runtime) (*Volume, error) {
 
 // teardownStorage deletes the volume from volumePath
 func (v *Volume) teardownStorage() error {
+	v.Unmount()
 	return os.RemoveAll(filepath.Join(v.runtime.config.VolumePath, v.Name()))
 }