server: Fetch StorageInfo() from underlying disks transparently. (#2549)

Fixes #2511

.travis.yml

@@ -4,9 +4,9 @@ language: go
 
 os:
 - linux
-- osx
+#- osx
 
-osx_image: xcode7.2
+#osx_image: xcode7.2
 
 env:
 - ARCH=x86_64

cmd/fs-v1.go

@@ -26,7 +26,6 @@ import (
 	"sort"
 	"strings"
 
-	"github.com/minio/minio/pkg/disk"
 	"github.com/minio/minio/pkg/mimedb"
 )
 
@@ -146,8 +145,8 @@ func (fs fsObjects) Shutdown() error {
 
 // StorageInfo - returns underlying storage statistics.
 func (fs fsObjects) StorageInfo() StorageInfo {
-	info, err := disk.GetInfo(fs.physicalDisk)
+	info, err := fs.storage.DiskInfo()
-	fatalIf(err, "Unable to get disk info "+fs.physicalDisk)
+	errorIf(err, "Unable to get disk info %#v", fs.storage)
 	return StorageInfo{
 		Total: info.Total,
 		Free:  info.Free,

cmd/posix.go

@@ -160,6 +160,12 @@ func checkDiskFree(diskPath string, minFreeDisk int64) (err error) {
 	return nil
 }
 
+// DiskInfo provides current information about disk space usage,
+// total free inodes and underlying filesystem.
+func (s *posix) DiskInfo() (info disk.Info, err error) {
+	return getDiskInfo(s.diskPath)
+}
+
 // getVolDir - will convert incoming volume names to
 // corresponding valid volume names on the backend in a platform
 // compatible way for all operating systems. If volume is not found

cmd/storage-interface.go

@@ -16,8 +16,13 @@
 
 package cmd
 
+import "github.com/minio/minio/pkg/disk"
+
 // StorageAPI interface.
 type StorageAPI interface {
+	// Storage operations.
+	DiskInfo() (info disk.Info, err error)
+
 	// Volume operations.
 	MakeVol(volume string) (err error)
 	ListVols() (vols []VolInfo, err error)

cmd/storage-rpc-client.go

@@ -21,6 +21,8 @@ import (
 	"path"
 	"strconv"
 	"strings"
+
+	"github.com/minio/minio/pkg/disk"
 )
 
 type networkStorage struct {
@@ -110,7 +112,16 @@ func newRPCClient(networkPath string) (StorageAPI, error) {
 	return ndisk, nil
 }
 
-// MakeVol - make a volume.
+// DiskInfo - fetch disk information for a remote disk.
+func (n networkStorage) DiskInfo() (info disk.Info, err error) {
+	args := GenericArgs{}
+	if err = n.rpcClient.Call("Storage.DiskInfoHandler", &args, &info); err != nil {
+		return disk.Info{}, err
+	}
+	return info, nil
+}
+
+// MakeVol - create a volume on a remote disk.
 func (n networkStorage) MakeVol(volume string) error {
 	reply := GenericReply{}
 	args := GenericVolArgs{Vol: volume}
@@ -120,7 +131,7 @@ func (n networkStorage) MakeVol(volume string) error {
 	return nil
 }
 
-// ListVols - List all volumes.
+// ListVols - List all volumes on a remote disk.
 func (n networkStorage) ListVols() (vols []VolInfo, err error) {
 	ListVols := ListVolsReply{}
 	err = n.rpcClient.Call("Storage.ListVolsHandler", &GenericArgs{}, &ListVols)

cmd/storage-rpc-server.go

@@ -24,6 +24,7 @@ import (
 	"strings"
 
 	router "github.com/gorilla/mux"
+	"github.com/minio/minio/pkg/disk"
 )
 
 // Storage server implements rpc primitives to facilitate exporting a
@@ -53,7 +54,19 @@ func (s *storageServer) LoginHandler(args *RPCLoginArgs, reply *RPCLoginReply) e
 	return nil
 }
 
-/// Volume operations handlers
+/// Storage operations handlers.
+
+// DiskInfoHandler - disk info handler is rpc wrapper for DiskInfo operation.
+func (s *storageServer) DiskInfoHandler(args *GenericArgs, reply *disk.Info) error {
+	if !isRPCTokenValid(args.Token) {
+		return errInvalidToken
+	}
+	info, err := s.storage.DiskInfo()
+	*reply = info
+	return err
+}
+
+/// Volume operations handlers.
 
 // MakeVolHandler - make vol handler is rpc wrapper for MakeVol operation.
 func (s *storageServer) MakeVolHandler(args *GenericVolArgs, reply *GenericReply) error {

cmd/xl-v1.go

@@ -50,12 +50,11 @@ const (
 
 // xlObjects - Implements XL object layer.
 type xlObjects struct {
-	physicalDisks []string     // Collection of regular disks.
+	storageDisks []StorageAPI // Collection of initialized backend disks.
-	storageDisks  []StorageAPI // Collection of initialized backend disks.
+	dataBlocks   int          // dataBlocks count caculated for erasure.
-	dataBlocks    int          // dataBlocks count caculated for erasure.
+	parityBlocks int          // parityBlocks count calculated for erasure.
-	parityBlocks  int          // parityBlocks count calculated for erasure.
+	readQuorum   int          // readQuorum minimum required disks to read data.
-	readQuorum    int          // readQuorum minimum required disks to read data.
+	writeQuorum  int          // writeQuorum minimum required disks to write data.
-	writeQuorum   int          // writeQuorum minimum required disks to write data.
 
 	// ListObjects pool management.
 	listPool *treeWalkPool
@@ -186,7 +185,6 @@ func newXLObjects(disks, ignoredDisks []string) (ObjectLayer, error) {
 
 	// Initialize xl objects.
 	xl := xlObjects{
-		physicalDisks:   disks,
 		storageDisks:    newPosixDisks,
 		dataBlocks:      dataBlocks,
 		parityBlocks:    parityBlocks,
@@ -222,10 +220,10 @@ func (d byDiskTotal) Less(i, j int) bool {
 // StorageInfo - returns underlying storage statistics.
 func (xl xlObjects) StorageInfo() StorageInfo {
 	var disksInfo []disk.Info
-	for _, diskPath := range xl.physicalDisks {
+	for _, storageDisk := range xl.storageDisks {
-		info, err := disk.GetInfo(diskPath)
+		info, err := storageDisk.DiskInfo()
 		if err != nil {
-			errorIf(err, "Unable to fetch disk info for "+diskPath)
+			errorIf(err, "Unable to fetch disk info for %#v", storageDisk)
 			continue
 		}
 		disksInfo = append(disksInfo, info)