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Diffstat (limited to 'weed/storage/volume_super_block.go')
-rw-r--r--weed/storage/volume_super_block.go103
1 files changed, 3 insertions, 100 deletions
diff --git a/weed/storage/volume_super_block.go b/weed/storage/volume_super_block.go
index 519691260..61c09d85a 100644
--- a/weed/storage/volume_super_block.go
+++ b/weed/storage/volume_super_block.go
@@ -1,79 +1,14 @@
package storage
import (
- "fmt"
"os"
"github.com/chrislusf/seaweedfs/weed/glog"
- "github.com/chrislusf/seaweedfs/weed/pb/master_pb"
"github.com/chrislusf/seaweedfs/weed/storage/backend"
"github.com/chrislusf/seaweedfs/weed/storage/needle"
- "github.com/chrislusf/seaweedfs/weed/util"
- "github.com/golang/protobuf/proto"
+ "github.com/chrislusf/seaweedfs/weed/storage/super_block"
)
-const (
- _SuperBlockSize = 8
-)
-
-/*
-* Super block currently has 8 bytes allocated for each volume.
-* Byte 0: version, 1 or 2
-* Byte 1: Replica Placement strategy, 000, 001, 002, 010, etc
-* Byte 2 and byte 3: Time to live. See TTL for definition
-* Byte 4 and byte 5: The number of times the volume has been compacted.
-* Rest bytes: Reserved
- */
-type SuperBlock struct {
- version needle.Version
- ReplicaPlacement *ReplicaPlacement
- Ttl *needle.TTL
- CompactionRevision uint16
- Extra *master_pb.SuperBlockExtra
- extraSize uint16
-}
-
-func (s *SuperBlock) BlockSize() int {
- switch s.version {
- case needle.Version2, needle.Version3:
- return _SuperBlockSize + int(s.extraSize)
- }
- return _SuperBlockSize
-}
-
-func (s *SuperBlock) Version() needle.Version {
- return s.version
-}
-func (s *SuperBlock) Bytes() []byte {
- header := make([]byte, _SuperBlockSize)
- header[0] = byte(s.version)
- header[1] = s.ReplicaPlacement.Byte()
- s.Ttl.ToBytes(header[2:4])
- util.Uint16toBytes(header[4:6], s.CompactionRevision)
-
- if s.Extra != nil {
- extraData, err := proto.Marshal(s.Extra)
- if err != nil {
- glog.Fatalf("cannot marshal super block extra %+v: %v", s.Extra, err)
- }
- extraSize := len(extraData)
- if extraSize > 256*256-2 {
- // reserve a couple of bits for future extension
- glog.Fatalf("super block extra size is %d bigger than %d", extraSize, 256*256-2)
- }
- s.extraSize = uint16(extraSize)
- util.Uint16toBytes(header[6:8], s.extraSize)
-
- header = append(header, extraData...)
- }
-
- return header
-}
-
-func (s *SuperBlock) Initialized() bool {
- return s.ReplicaPlacement != nil && s.Ttl != nil
-}
-
func (v *Volume) maybeWriteSuperBlock() error {
datSize, _, e := v.DataBackend.GetStat()
@@ -82,7 +17,7 @@ func (v *Volume) maybeWriteSuperBlock() error {
return e
}
if datSize == 0 {
- v.SuperBlock.version = needle.CurrentVersion
+ v.SuperBlock.Version = needle.CurrentVersion
_, e = v.DataBackend.WriteAt(v.SuperBlock.Bytes(), 0)
if e != nil && os.IsPermission(e) {
//read-only, but zero length - recreate it!
@@ -100,38 +35,6 @@ func (v *Volume) maybeWriteSuperBlock() error {
}
func (v *Volume) readSuperBlock() (err error) {
- v.SuperBlock, err = ReadSuperBlock(v.DataBackend)
+ v.SuperBlock, err = super_block.ReadSuperBlock(v.DataBackend)
return err
}
-
-// ReadSuperBlock reads from data file and load it into volume's super block
-func ReadSuperBlock(datBackend backend.BackendStorageFile) (superBlock SuperBlock, err error) {
-
- header := make([]byte, _SuperBlockSize)
- if _, e := datBackend.ReadAt(header, 0); e != nil {
- err = fmt.Errorf("cannot read volume %s super block: %v", datBackend.Name(), e)
- return
- }
-
- superBlock.version = needle.Version(header[0])
- if superBlock.ReplicaPlacement, err = NewReplicaPlacementFromByte(header[1]); err != nil {
- err = fmt.Errorf("cannot read replica type: %s", err.Error())
- return
- }
- superBlock.Ttl = needle.LoadTTLFromBytes(header[2:4])
- superBlock.CompactionRevision = util.BytesToUint16(header[4:6])
- superBlock.extraSize = util.BytesToUint16(header[6:8])
-
- if superBlock.extraSize > 0 {
- // read more
- extraData := make([]byte, int(superBlock.extraSize))
- superBlock.Extra = &master_pb.SuperBlockExtra{}
- err = proto.Unmarshal(extraData, superBlock.Extra)
- if err != nil {
- err = fmt.Errorf("cannot read volume %s super block extra: %v", datBackend.Name(), err)
- return
- }
- }
-
- return
-}