Merge pull request #636 from teawater/cache2

Add new option "cache" to container and volume

Author: laijs

api/descriptions.pb.go

@@ -48,6 +48,7 @@ message VolumeDescription {
     string source = 2;
     string format = 3; //"raw" (or "qcow2" later) for volume, "vfs" for dir path
     string fstype = 4; //"xfs", "ext4" etc. for block dev, or "dir" for dir path
+    string cache = 5;
     VolumeOption options = 8;
     bool dockerVolume = 9;
     bool readOnly = 10;

api/descriptions.proto

@@ -19,6 +19,7 @@ type DiskDescriptor struct {
 	ScsiAddr     string
 	DockerVolume bool
 	ReadOnly     bool
+	Cache        string
 	Options      map[string]string
 }
 
@@ -49,6 +50,7 @@ func NewDiskContext(ctx *VmContext, vol *api.VolumeDescription) *DiskContext {
 			Fstype:       vol.Fstype,
 			DockerVolume: vol.DockerVolume,
 			ReadOnly:     vol.ReadOnly,
+			Cache:        vol.Cache,
 		},
 		sandbox:   ctx,
 		observers: make(map[string]*sync.WaitGroup),

hypervisor/disk.go

@@ -26,6 +26,7 @@ type PersistVolumeInfo struct {
 	Filename     string
 	Format       string
 	Fstype       string
+	Cache        string
 	DeviceName   string
 	ScsiId       int
 	ContainerIds []string
@@ -178,6 +179,7 @@ func (blk *DiskDescriptor) dump() *PersistVolumeInfo {
 		Filename:   blk.Filename,
 		Format:     blk.Format,
 		Fstype:     blk.Fstype,
+		Cache:      blk.Cache,
 		DeviceName: blk.DeviceName,
 		ScsiId:     blk.ScsiId,
 	}
@@ -189,6 +191,7 @@ func (vol *PersistVolumeInfo) blockInfo() *DiskDescriptor {
 		Filename:   vol.Filename,
 		Format:     vol.Format,
 		Fstype:     vol.Fstype,
+		Cache:      vol.Cache,
 		DeviceName: vol.DeviceName,
 		ScsiId:     vol.ScsiId,
 	}
@@ -331,6 +334,7 @@ func (pinfo *PersistInfo) vmContext(hub chan VmEvent, client chan *types.VmRespo
 					Source:       bInfo.Filename,
 					Format:       bInfo.Format,
 					Fstype:       bInfo.Fstype,
+					Cache:        bInfo.Cache,
 					DockerVolume: bInfo.DockerVolume,
 					ReadOnly:     bInfo.ReadOnly,
 				},

hypervisor/persistence.go

@@ -241,6 +241,7 @@ func (qc *QemuContext) AddDisk(ctx *hypervisor.VmContext, sourceType string, blo
 	format := blockInfo.Format
 	id := blockInfo.ScsiId
 	readonly := blockInfo.ReadOnly
+	cache := blockInfo.Cache
 
 	if format == "rbd" {
 		if blockInfo.Options != nil {
@@ -262,7 +263,7 @@ func (qc *QemuContext) AddDisk(ctx *hypervisor.VmContext, sourceType string, blo
 		}
 	}
 
-	newDiskAddSession(ctx, qc, filename, format, id, readonly, result)
+	newDiskAddSession(ctx, qc, filename, format, id, readonly, cache, result)
 }
 
 func (qc *QemuContext) RemoveDisk(ctx *hypervisor.VmContext, blockInfo *hypervisor.DiskDescriptor, callback hypervisor.VmEvent, result chan<- hypervisor.VmEvent) {

hypervisor/qemu/qemu.go

@@ -35,8 +35,11 @@ func defaultRespond(result chan<- hypervisor.VmEvent, callback hypervisor.VmEven
 	}
 }
 
-func newDiskAddSession(ctx *hypervisor.VmContext, qc *QemuContext, filename, format string, id int, readonly bool, result chan<- hypervisor.VmEvent) {
-	args := "drive_add dummy file=" + filename + ",if=none,id=" + "drive" + strconv.Itoa(id) + ",format=" + format + ",cache=writeback"
+func newDiskAddSession(ctx *hypervisor.VmContext, qc *QemuContext, filename, format string, id int, readonly bool, cache string, result chan<- hypervisor.VmEvent) {
+	if cache == "" {
+		cache = "writeback"
+	}
+	args := "drive_add dummy file=" + filename + ",if=none,id=" + "drive" + strconv.Itoa(id) + ",format=" + format + ",cache=" + cache
 	if readonly {
 		args += ",readonly"
 	}