refactor: make all quota implementation logic clear

apis/swagger.yml

@@ -1964,7 +1964,12 @@ definitions:
         description: "Initial script executed in container. The script will be executed before entrypoint or command"
       DiskQuota:
         type: "object"
-        description: "Set disk quota for container"
+        description: |
+          Set disk quota for container.
+          Key is the dir in container.
+          Value is disk quota size for the dir.
+          / means rootfs dir in container.
+          .* includes rootfs dir and all volume dir.
         x-nullable: true
         additionalProperties:
           type: "string"
@@ -1975,7 +1980,10 @@ definitions:
           type: "string"
       QuotaID:
         type: "string"
-        description: "set disk quota by specified quota id, if id < 0, it means pouchd alloc a unique quota id"
+        description: |
+          Set disk quota by specified quota id. 
+          If QuotaID <= 0, it means pouchd should allocate a unique quota id by sequence automatically.
+          By default, a quota ID is mapped to only one container. And one quota ID can include several mountpoint.
       NetPriority:
         description: "net priority."
         type: "integer"

daemon/mgr/container.go

@@ -1095,7 +1095,7 @@ func (mgr *ContainerManager) updateContainerDiskQuota(ctx context.Context, c *Co
 		qid = uint32(id)
 		if id < 0 {
 			// QuotaID is < 0, it means pouchd alloc a unique quota id.
-			qid, err = quota.GetNextQuatoID()
+			qid, err = quota.GetNextQuotaID()
 			if err != nil {
 				return errors.Wrap(err, "failed to get next quota id")
 			}
@@ -2250,7 +2250,7 @@ func (mgr *ContainerManager) setMountPointDiskQuota(ctx context.Context, c *Cont
 
 		// if QuotaID is < 0, it means pouchd alloc a unique quota id.
 		if id < 0 {
-			qid, err = quota.GetNextQuatoID()
+			qid, err = quota.GetNextQuotaID()
 			if err != nil {
 				return errors.Wrap(err, "failed to get next quota id")
 			}

daemon/mgr/spec_hook.go

@@ -10,6 +10,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/alibaba/pouch/pkg/system"
 	"github.com/alibaba/pouch/storage/quota"
 
 	specs "github.com/opencontainers/runtime-spec/specs-go"
@@ -98,7 +99,7 @@ func setMountTab(ctx context.Context, c *Container, spec *SpecWrapper) error {
 
 	// set rootfs mount tab
 	context := "/ / ext4 rw 0 0\n"
-	if rootID, e := quota.GetDevID(c.BaseFS); e == nil {
+	if rootID, e := system.GetDevID(c.BaseFS); e == nil {
 		_, _, rootFsType := quota.CheckMountpoint(rootID)
 		if len(rootFsType) > 0 {
 			context = fmt.Sprintf("/ / %s rw 0 0\n", rootFsType)
@@ -118,7 +119,7 @@ func setMountTab(ctx context.Context, c *Container, spec *SpecWrapper) error {
 		}
 
 		tempLine := fmt.Sprintf("/dev/v%02dd %s ext4 rw 0 0\n", i, m.Destination)
-		if tmpID, e := quota.GetDevID(m.Source); e == nil {
+		if tmpID, e := system.GetDevID(m.Source); e == nil {
 			_, _, fsType := quota.CheckMountpoint(tmpID)
 			if len(fsType) > 0 {
 				tempLine = fmt.Sprintf("/dev/v%02dd %s %s rw 0 0\n", i, m.Destination, fsType)

pkg/system/device.go

@@ -0,0 +1,19 @@
+// +build linux
+
+package system
+
+import (
+	"syscall"
+
+	"github.com/sirupsen/logrus"
+)
+
+// GetDevID returns device id via syscall according to the input directory.
+func GetDevID(dir string) (uint64, error) {
+	var st syscall.Stat_t
+	if err := syscall.Stat(dir, &st); err != nil {
+		logrus.Warnf("failed to get device id of dir %s: %v", dir, err)
+		return 0, err
+	}
+	return st.Dev, nil
+}

pkg/system/sysinfo.go

@@ -1,3 +1,5 @@
+// +build linux
+
 package system
 
 import (