minio/cmd/xl-storage-format-v2.go
2020-06-22 17:27:54 -07:00

607 lines
18 KiB
Go

/*
* MinIO Cloud Storage, (C) 2020 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"bytes"
"fmt"
"strings"
"time"
"github.com/google/uuid"
"github.com/minio/minio/cmd/logger"
)
var (
// XL header specifies the format
xlHeader = [4]byte{'X', 'L', '2', ' '}
// XLv2 version 1
xlVersionV1 = [4]byte{'1', ' ', ' ', ' '}
)
func checkXL2V1(buf []byte) error {
if len(buf) <= 8 {
return fmt.Errorf("xlMeta: no data")
}
if !bytes.Equal(buf[:4], xlHeader[:]) {
return fmt.Errorf("xlMeta: unknown XLv2 header, expected %v, got %v", xlHeader[:4], buf[:4])
}
if !bytes.Equal(buf[4:8], xlVersionV1[:]) {
return fmt.Errorf("xlMeta: unknown XLv2 version, expected %v, got %v", xlVersionV1[:4], buf[4:8])
}
return nil
}
func isXL2V1Format(buf []byte) bool {
return checkXL2V1(buf) == nil
}
// The []journal contains all the different versions of the object.
//
// This array can have 3 kinds of objects:
//
// ``object``: If the object is uploaded the usual way: putobject, multipart-put, copyobject
//
// ``delete``: This is the delete-marker
//
// ``legacyObject``: This is the legacy object in xlV1 format, preserved until its overwritten
//
// The most recently updated element in the array is considered the latest version.
// Backend directory tree structure:
// disk1/
// └── bucket
// └── object
// ├── a192c1d5-9bd5-41fd-9a90-ab10e165398d
// │ └── part.1
// ├── c06e0436-f813-447e-ae5e-f2564df9dfd4
// │ └── part.1
// ├── df433928-2dcf-47b1-a786-43efa0f6b424
// │ └── part.1
// ├── legacy
// │ └── part.1
// └── xl.meta
//go:generate msgp -file=$GOFILE -unexported
// VersionType defines the type of journal type of the current entry.
type VersionType uint8
// List of different types of journal type
const (
invalidVersionType VersionType = 0
ObjectType VersionType = 1
DeleteType VersionType = 2
LegacyType VersionType = 3
lastVersionType VersionType = 4
)
func (e VersionType) valid() bool {
return e > invalidVersionType && e < lastVersionType
}
// ErasureAlgo defines common type of different erasure algorithms
type ErasureAlgo uint8
// List of currently supported erasure coding algorithms
const (
invalidErasureAlgo ErasureAlgo = 0
ReedSolomon ErasureAlgo = 1
lastErasureAlgo ErasureAlgo = 2
)
func (e ErasureAlgo) valid() bool {
return e > invalidErasureAlgo && e < lastErasureAlgo
}
func (e ErasureAlgo) String() string {
switch e {
case ReedSolomon:
return "reedsolomon"
}
return ""
}
// ChecksumAlgo defines common type of different checksum algorithms
type ChecksumAlgo uint8
// List of currently supported checksum algorithms
const (
invalidChecksumAlgo ChecksumAlgo = 0
HighwayHash ChecksumAlgo = 1
lastChecksumAlgo ChecksumAlgo = 2
)
func (e ChecksumAlgo) valid() bool {
return e > invalidChecksumAlgo && e < lastChecksumAlgo
}
// xlMetaV2DeleteMarker defines the data struct for the delete marker journal type
type xlMetaV2DeleteMarker struct {
VersionID [16]byte `json:"ID" msg:"ID"` // Version ID for delete marker
ModTime int64 `json:"MTime" msg:"MTime"` // Object delete marker modified time
}
// xlMetaV2Object defines the data struct for object journal type
type xlMetaV2Object struct {
VersionID [16]byte `json:"ID" msg:"ID"` // Version ID
DataDir [16]byte `json:"DDir" msg:"DDir"` // Data dir ID
ErasureAlgorithm ErasureAlgo `json:"EcAlgo" msg:"EcAlgo"` // Erasure coding algorithm
ErasureM int `json:"EcM" msg:"EcM"` // Erasure data blocks
ErasureN int `json:"EcN" msg:"EcN"` // Erasure parity blocks
ErasureBlockSize int64 `json:"EcBSize" msg:"EcBSize"` // Erasure block size
ErasureIndex int `json:"EcIndex" msg:"EcIndex"` // Erasure disk index
ErasureDist []uint8 `json:"EcDist" msg:"EcDist"` // Erasure distribution
BitrotChecksumAlgo ChecksumAlgo `json:"CSumAlgo" msg:"CSumAlgo"` // Bitrot checksum algo
PartNumbers []int `json:"PartNums" msg:"PartNums"` // Part Numbers
PartETags []string `json:"PartETags" msg:"PartETags"` // Part ETags
PartSizes []int64 `json:"PartSizes" msg:"PartSizes"` // Part Sizes
PartActualSizes []int64 `json:"PartASizes,omitempty" msg:"PartASizes,omitempty"` // Part ActualSizes (compression)
StatSize int64 `json:"Size" msg:"Size"` // Object version size
StatModTime int64 `json:"MTime" msg:"MTime"` // Object version modified time
MetaSys map[string][]byte `json:"MetaSys,omitempty" msg:"MetaSys,omitempty"` // Object version internal metadata
MetaUser map[string]string `json:"MetaUsr,omitempty" msg:"MetaUsr,omitempty"` // Object version metadata set by user
}
// xlMetaV2Version describes the jouranal entry, Type defines
// the current journal entry type other types might be nil based
// on what Type field carries, it is imperative for the caller
// to verify which journal type first before accessing rest of the fields.
type xlMetaV2Version struct {
Type VersionType `json:"Type" msg:"Type"`
ObjectV1 *xlMetaV1Object `json:"V1Obj,omitempty" msg:"V1Obj,omitempty"`
ObjectV2 *xlMetaV2Object `json:"V2Obj,omitempty" msg:"V2Obj,omitempty"`
DeleteMarker *xlMetaV2DeleteMarker `json:"DelObj,omitempty" msg:"DelObj,omitempty"`
}
// Valid xl meta xlMetaV2Version is valid
func (j xlMetaV2Version) Valid() bool {
switch j.Type {
case LegacyType:
return j.ObjectV1 != nil &&
j.ObjectV1.valid()
case ObjectType:
return j.ObjectV2 != nil &&
j.ObjectV2.ErasureAlgorithm.valid() &&
j.ObjectV2.BitrotChecksumAlgo.valid() &&
isXLMetaErasureInfoValid(j.ObjectV2.ErasureM, j.ObjectV2.ErasureN) &&
j.ObjectV2.StatModTime > 0
case DeleteType:
return j.DeleteMarker != nil &&
j.DeleteMarker.ModTime > 0
}
return false
}
// xlMetaV2 - object meta structure defines the format and list of
// the journals for the object.
type xlMetaV2 struct {
Versions []xlMetaV2Version `json:"Versions" msg:"Versions"`
}
// AddLegacy adds a legacy version, is only called when no prior
// versions exist, safe to use it by only one function in xl-storage(RenameData)
func (z *xlMetaV2) AddLegacy(m *xlMetaV1Object) error {
if !m.valid() {
return errFileCorrupt
}
m.VersionID = nullVersionID
m.DataDir = legacyDataDir
z.Versions = []xlMetaV2Version{
{
Type: LegacyType,
ObjectV1: m,
},
}
return nil
}
// Load unmarshal and load the entire message pack.
func (z *xlMetaV2) Load(buf []byte) error {
if err := checkXL2V1(buf); err != nil {
return err
}
_, err := z.UnmarshalMsg(buf[8:])
return err
}
// AddVersion adds a new version
func (z *xlMetaV2) AddVersion(fi FileInfo) error {
if fi.Deleted {
uv, err := uuid.Parse(fi.VersionID)
if err != nil {
return err
}
z.Versions = append(z.Versions, xlMetaV2Version{
Type: DeleteType,
DeleteMarker: &xlMetaV2DeleteMarker{
VersionID: uv,
ModTime: fi.ModTime.UnixNano(),
},
})
return nil
}
if fi.VersionID == "" {
// this means versioning is not yet
// enabled i.e all versions are basically
// default value i.e "null"
fi.VersionID = nullVersionID
}
var uv uuid.UUID
var err error
if fi.VersionID != "" && fi.VersionID != nullVersionID {
uv, err = uuid.Parse(fi.VersionID)
if err != nil {
return err
}
}
dd, err := uuid.Parse(fi.DataDir)
if err != nil {
return err
}
ventry := xlMetaV2Version{
Type: ObjectType,
ObjectV2: &xlMetaV2Object{
VersionID: uv,
DataDir: dd,
StatSize: fi.Size,
StatModTime: fi.ModTime.UnixNano(),
ErasureAlgorithm: ReedSolomon,
ErasureM: fi.Erasure.DataBlocks,
ErasureN: fi.Erasure.ParityBlocks,
ErasureBlockSize: fi.Erasure.BlockSize,
ErasureIndex: fi.Erasure.Index,
BitrotChecksumAlgo: HighwayHash,
ErasureDist: make([]uint8, len(fi.Erasure.Distribution)),
PartNumbers: make([]int, len(fi.Parts)),
PartETags: make([]string, len(fi.Parts)),
PartSizes: make([]int64, len(fi.Parts)),
PartActualSizes: make([]int64, len(fi.Parts)),
MetaSys: make(map[string][]byte),
MetaUser: make(map[string]string),
},
}
for i := range fi.Erasure.Distribution {
ventry.ObjectV2.ErasureDist[i] = uint8(fi.Erasure.Distribution[i])
}
for i := range fi.Parts {
ventry.ObjectV2.PartSizes[i] = fi.Parts[i].Size
if fi.Parts[i].ETag != "" {
ventry.ObjectV2.PartETags[i] = fi.Parts[i].ETag
}
ventry.ObjectV2.PartNumbers[i] = fi.Parts[i].Number
ventry.ObjectV2.PartActualSizes[i] = fi.Parts[i].ActualSize
}
for k, v := range fi.Metadata {
if strings.HasPrefix(strings.ToLower(k), ReservedMetadataPrefixLower) {
ventry.ObjectV2.MetaSys[k] = []byte(v)
} else {
ventry.ObjectV2.MetaUser[k] = v
}
}
for i, version := range z.Versions {
if !version.Valid() {
return errFileCorrupt
}
switch version.Type {
case LegacyType:
// This would convert legacy type into new ObjectType
// this means that we are basically purging the `null`
// version of the object.
if version.ObjectV1.VersionID == fi.VersionID {
z.Versions[i] = ventry
return nil
}
case ObjectType:
if bytes.Equal(version.ObjectV2.VersionID[:], uv[:]) {
z.Versions[i] = ventry
return nil
}
case DeleteType:
// Allowing delete marker to replaced with an proper
// object data type as well, this is not S3 complaint
// behavior but kept here for future flexibility.
if bytes.Equal(version.DeleteMarker.VersionID[:], uv[:]) {
z.Versions[i] = ventry
return nil
}
}
}
z.Versions = append(z.Versions, ventry)
return nil
}
func newXLMetaV2(fi FileInfo) (xlMetaV2, error) {
xlMeta := xlMetaV2{}
return xlMeta, xlMeta.AddVersion(fi)
}
func (j xlMetaV2DeleteMarker) ToFileInfo(volume, path string) (FileInfo, error) {
fi := FileInfo{
Volume: volume,
Name: path,
ModTime: time.Unix(0, j.ModTime).UTC(),
VersionID: uuid.UUID(j.VersionID).String(),
Deleted: true,
}
return fi, nil
}
func (j xlMetaV2Object) ToFileInfo(volume, path string) (FileInfo, error) {
versionID := ""
var uv uuid.UUID
// check if the version is not "null"
if !bytes.Equal(j.VersionID[:], uv[:]) {
versionID = uuid.UUID(j.VersionID).String()
}
fi := FileInfo{
Volume: volume,
Name: path,
Size: j.StatSize,
ModTime: time.Unix(0, j.StatModTime).UTC(),
VersionID: versionID,
}
fi.Parts = make([]ObjectPartInfo, len(j.PartNumbers))
for i := range fi.Parts {
fi.Parts[i].Number = int(j.PartNumbers[i])
fi.Parts[i].Size = int64(j.PartSizes[i])
fi.Parts[i].ETag = j.PartETags[i]
fi.Parts[i].ActualSize = int64(j.PartActualSizes[i])
}
fi.Erasure.Checksums = make([]ChecksumInfo, len(j.PartSizes))
for i := range fi.Parts {
fi.Erasure.Checksums[i].PartNumber = fi.Parts[i].Number
switch j.BitrotChecksumAlgo {
case HighwayHash:
fi.Erasure.Checksums[i].Algorithm = HighwayHash256S
fi.Erasure.Checksums[i].Hash = []byte{}
default:
return FileInfo{}, fmt.Errorf("unknown BitrotChecksumAlgo: %v", j.BitrotChecksumAlgo)
}
}
fi.Metadata = make(map[string]string, len(j.MetaUser)+len(j.MetaSys))
for k, v := range j.MetaUser {
fi.Metadata[k] = v
}
for k, v := range j.MetaSys {
if strings.HasPrefix(strings.ToLower(k), ReservedMetadataPrefixLower) {
fi.Metadata[k] = string(v)
}
}
fi.Erasure.Algorithm = j.ErasureAlgorithm.String()
fi.Erasure.Index = j.ErasureIndex
fi.Erasure.BlockSize = j.ErasureBlockSize
fi.Erasure.DataBlocks = j.ErasureM
fi.Erasure.ParityBlocks = j.ErasureN
fi.Erasure.Distribution = make([]int, len(j.ErasureDist))
for i := range j.ErasureDist {
fi.Erasure.Distribution[i] = int(j.ErasureDist[i])
}
fi.DataDir = uuid.UUID(j.DataDir).String()
return fi, nil
}
// DeleteVersion deletes the version specified by version id.
// returns to the caller which dataDir to delete, also
// indicates if this is the last version.
func (z *xlMetaV2) DeleteVersion(fi FileInfo) (string, bool, error) {
// This is a situation where versionId is explicitly
// specified as "null", as we do not save "null"
// string it is considered empty. But empty also
// means the version which matches will be purged.
if fi.VersionID == nullVersionID {
fi.VersionID = ""
}
var uv uuid.UUID
if fi.VersionID != "" {
uv, _ = uuid.Parse(fi.VersionID)
}
for i, version := range z.Versions {
if !version.Valid() {
return "", false, errFileCorrupt
}
switch version.Type {
case LegacyType:
if version.ObjectV1.VersionID == fi.VersionID {
z.Versions = append(z.Versions[:i], z.Versions[i+1:]...)
return version.ObjectV1.DataDir, len(z.Versions) == 0, nil
}
case ObjectType:
if bytes.Equal(version.ObjectV2.VersionID[:], uv[:]) {
z.Versions = append(z.Versions[:i], z.Versions[i+1:]...)
return uuid.UUID(version.ObjectV2.DataDir).String(), len(z.Versions) == 0, nil
}
case DeleteType:
if bytes.Equal(version.DeleteMarker.VersionID[:], uv[:]) {
z.Versions = append(z.Versions[:i], z.Versions[i+1:]...)
return "", len(z.Versions) == 0, nil
}
}
}
return "", false, errFileVersionNotFound
}
// TotalSize returns the total size of all versions.
func (z xlMetaV2) TotalSize() int64 {
var total int64
for i := range z.Versions {
switch z.Versions[i].Type {
case ObjectType:
total += z.Versions[i].ObjectV2.StatSize
case LegacyType:
total += z.Versions[i].ObjectV1.Stat.Size
}
}
return total
}
// ListVersions lists current versions, and current deleted
// versions returns error for unexpected entries.
func (z xlMetaV2) ListVersions(volume, path string) (versions []FileInfo, deleted []FileInfo, modTime time.Time, err error) {
var latestModTime time.Time
var latestVersionID string
for _, version := range z.Versions {
if !version.Valid() {
return nil, nil, latestModTime, errFileCorrupt
}
var fi FileInfo
switch version.Type {
case ObjectType:
fi, err = version.ObjectV2.ToFileInfo(volume, path)
case DeleteType:
fi, err = version.DeleteMarker.ToFileInfo(volume, path)
case LegacyType:
fi, err = version.ObjectV1.ToFileInfo(volume, path)
default:
continue
}
if err != nil {
return nil, nil, latestModTime, err
}
if fi.ModTime.After(latestModTime) {
latestModTime = fi.ModTime
latestVersionID = fi.VersionID
}
switch version.Type {
case LegacyType:
fallthrough
case ObjectType:
versions = append(versions, fi)
case DeleteType:
deleted = append(deleted, fi)
}
}
// Since we can never have duplicate versions the versionID
// if it matches first with deleted markers then we are sure
// that actual versions wouldn't be latest, so we can return
// early if we find the version in delete markers.
for i := range deleted {
if deleted[i].VersionID == latestVersionID {
deleted[i].IsLatest = true
return versions, deleted, latestModTime, nil
}
}
// We didn't find the version in delete markers so latest version
// is indeed one of the actual version of the object with data.
for i := range versions {
if versions[i].VersionID != latestVersionID {
continue
}
versions[i].IsLatest = true
break
}
return versions, deleted, latestModTime, nil
}
// ToFileInfo converts xlMetaV2 into a common FileInfo datastructure
// for consumption across callers.
func (z xlMetaV2) ToFileInfo(volume, path, versionID string) (FileInfo, error) {
var uv uuid.UUID
if versionID != "" {
uv, _ = uuid.Parse(versionID)
}
if versionID == "" {
var latestModTime time.Time
var latestIndex int
for i, version := range z.Versions {
if !version.Valid() {
logger.LogIf(GlobalContext, fmt.Errorf("invalid version detected %#v", version))
return FileInfo{}, errFileNotFound
}
var modTime time.Time
switch version.Type {
case ObjectType:
modTime = time.Unix(0, version.ObjectV2.StatModTime)
case DeleteType:
modTime = time.Unix(0, version.DeleteMarker.ModTime)
case LegacyType:
modTime = version.ObjectV1.Stat.ModTime
default:
continue
}
if modTime.After(latestModTime) {
latestModTime = modTime
latestIndex = i
}
}
if len(z.Versions) >= 1 {
switch z.Versions[latestIndex].Type {
case ObjectType:
return z.Versions[latestIndex].ObjectV2.ToFileInfo(volume, path)
case DeleteType:
return z.Versions[latestIndex].DeleteMarker.ToFileInfo(volume, path)
case LegacyType:
return z.Versions[latestIndex].ObjectV1.ToFileInfo(volume, path)
}
}
return FileInfo{}, errFileNotFound
}
for _, version := range z.Versions {
if !version.Valid() {
logger.LogIf(GlobalContext, fmt.Errorf("invalid version detected %#v", version))
if versionID == "" {
return FileInfo{}, errFileNotFound
}
return FileInfo{}, errFileVersionNotFound
}
switch version.Type {
case ObjectType:
if bytes.Equal(version.ObjectV2.VersionID[:], uv[:]) {
return version.ObjectV2.ToFileInfo(volume, path)
}
case LegacyType:
if version.ObjectV1.VersionID == versionID {
return version.ObjectV1.ToFileInfo(volume, path)
}
case DeleteType:
if bytes.Equal(version.DeleteMarker.VersionID[:], uv[:]) {
return version.DeleteMarker.ToFileInfo(volume, path)
}
default:
logger.LogIf(GlobalContext, fmt.Errorf("unknown version type: %v", version.Type))
if versionID == "" {
return FileInfo{}, errFileNotFound
}
return FileInfo{}, errFileVersionNotFound
}
}
if versionID == "" {
return FileInfo{}, errFileNotFound
}
return FileInfo{}, errFileVersionNotFound
}