mirror of
https://github.com/pgsty/minio.git
synced 2026-08-09 07:43:29 +03:00
xl: code refactor, cleanup ReadFile and CreateFile.
This commit is contained in:
Krishna Srinivas
committed by
Harshavardhana
Harshavardhana
parent
45b3d3e21f
commit
5c33b68318
+80
-113
@@ -17,7 +17,6 @@
|
||||
package main
|
||||
|
||||
import (
|
||||
"encoding/json"
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
@@ -44,85 +43,66 @@ func getEncodedBlockLen(inputLen, dataBlocks int) (curBlockSize int) {
|
||||
return
|
||||
}
|
||||
|
||||
func (xl XL) getMetaFileVersionMap(volume, path string) (diskFileVersionMap map[int]int64) {
|
||||
metadataFilePath := slashpath.Join(path, metadataFile)
|
||||
// Set offset to 0 to read entire file.
|
||||
offset := int64(0)
|
||||
metadata := make(map[string]string)
|
||||
|
||||
// Allocate disk index format map - do not use maps directly without allocating.
|
||||
diskFileVersionMap = make(map[int]int64)
|
||||
|
||||
// TODO - all errors should be logged here.
|
||||
|
||||
// Read meta data from all disks
|
||||
for index, disk := range xl.storageDisks {
|
||||
diskFileVersionMap[index] = -1
|
||||
|
||||
metadataReader, err := disk.ReadFile(volume, metadataFilePath, offset)
|
||||
if err != nil {
|
||||
continue
|
||||
} else if err = json.NewDecoder(metadataReader).Decode(&metadata); err != nil {
|
||||
continue
|
||||
} else if _, ok := metadata["file.version"]; !ok {
|
||||
diskFileVersionMap[index] = 0
|
||||
}
|
||||
// Convert string to integer.
|
||||
fileVersion, err := strconv.ParseInt(metadata["file.version"], 10, 64)
|
||||
if err != nil {
|
||||
continue
|
||||
}
|
||||
diskFileVersionMap[index] = fileVersion
|
||||
}
|
||||
return diskFileVersionMap
|
||||
}
|
||||
|
||||
type quorumDisk struct {
|
||||
disk StorageAPI
|
||||
index int
|
||||
}
|
||||
|
||||
// getQuorumDisks - get the current quorum disks.
|
||||
func (xl XL) getQuorumDisks(volume, path string) (quorumDisks []quorumDisk, higherVersion int64) {
|
||||
diskVersionMap := xl.getMetaFileVersionMap(volume, path)
|
||||
for diskIndex, formatVersion := range diskVersionMap {
|
||||
if formatVersion > higherVersion {
|
||||
higherVersion = formatVersion
|
||||
quorumDisks = []quorumDisk{{
|
||||
disk: xl.storageDisks[diskIndex],
|
||||
index: diskIndex,
|
||||
}}
|
||||
} else if formatVersion == higherVersion {
|
||||
quorumDisks = append(quorumDisks, quorumDisk{
|
||||
disk: xl.storageDisks[diskIndex],
|
||||
index: diskIndex,
|
||||
})
|
||||
// Returns slice of disks needed for ReadFile operation:
|
||||
// - slice returing readable disks.
|
||||
// - file size
|
||||
// - error if any.
|
||||
func (xl XL) getReadableDisks(volume, path string) ([]StorageAPI, int64, error) {
|
||||
partsMetadata, errs := xl.getPartsMetadata(volume, path)
|
||||
highestVersion := int64(0)
|
||||
versions := make([]int64, len(xl.storageDisks))
|
||||
quorumDisks := make([]StorageAPI, len(xl.storageDisks))
|
||||
fileSize := int64(0)
|
||||
for index, metadata := range partsMetadata {
|
||||
if errs[index] == nil {
|
||||
if versionStr, ok := metadata["file.version"]; ok {
|
||||
// Convert string to integer.
|
||||
version, err := strconv.ParseInt(versionStr, 10, 64)
|
||||
if err != nil {
|
||||
// Unexpected, return error.
|
||||
return nil, 0, err
|
||||
}
|
||||
if version > highestVersion {
|
||||
highestVersion = version
|
||||
}
|
||||
versions[index] = version
|
||||
} else {
|
||||
versions[index] = 0
|
||||
}
|
||||
} else {
|
||||
versions[index] = -1
|
||||
}
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// getFileSize - extract file size from metadata.
|
||||
func (xl XL) getFileSize(volume, path string, disk StorageAPI) (size int64, err error) {
|
||||
metadataFilePath := slashpath.Join(path, metadataFile)
|
||||
// set offset to 0 to read entire file
|
||||
offset := int64(0)
|
||||
metadata := make(map[string]string)
|
||||
|
||||
metadataReader, err := disk.ReadFile(volume, metadataFilePath, offset)
|
||||
if err != nil {
|
||||
return 0, err
|
||||
quorumCount := 0
|
||||
for index, version := range versions {
|
||||
if version == highestVersion {
|
||||
quorumDisks[index] = xl.storageDisks[index]
|
||||
quorumCount++
|
||||
} else {
|
||||
quorumDisks[index] = nil
|
||||
}
|
||||
}
|
||||
if quorumCount < xl.readQuorum {
|
||||
return nil, 0, errReadQuorum
|
||||
}
|
||||
|
||||
if err = json.NewDecoder(metadataReader).Decode(&metadata); err != nil {
|
||||
return 0, err
|
||||
for index, disk := range quorumDisks {
|
||||
if disk == nil {
|
||||
continue
|
||||
}
|
||||
if sizeStr, ok := partsMetadata[index]["file.size"]; ok {
|
||||
var err error
|
||||
fileSize, err = strconv.ParseInt(sizeStr, 10, 64)
|
||||
if err != nil {
|
||||
return nil, 0, err
|
||||
}
|
||||
break
|
||||
} else {
|
||||
return nil, 0, errors.New("Missing 'file.size' in meta data.")
|
||||
}
|
||||
}
|
||||
|
||||
if _, ok := metadata["file.size"]; !ok {
|
||||
return 0, errors.New("missing 'file.size' in meta data")
|
||||
}
|
||||
|
||||
return strconv.ParseInt(metadata["file.size"], 10, 64)
|
||||
return quorumDisks, fileSize, nil
|
||||
}
|
||||
|
||||
// ReadFile - read file
|
||||
@@ -140,43 +120,23 @@ func (xl XL) ReadFile(volume, path string, offset int64) (io.ReadCloser, error)
|
||||
xl.lockNS(volume, path, readLock)
|
||||
defer xl.unlockNS(volume, path, readLock)
|
||||
|
||||
// Check read quorum.
|
||||
quorumDisks, _ := xl.getQuorumDisks(volume, path)
|
||||
if len(quorumDisks) < xl.readQuorum {
|
||||
return nil, errReadQuorum
|
||||
}
|
||||
|
||||
// Get file size.
|
||||
fileSize, err := xl.getFileSize(volume, path, quorumDisks[0].disk)
|
||||
quorumDisks, fileSize, err := xl.getReadableDisks(volume, path)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
totalBlocks := xl.DataBlocks + xl.ParityBlocks // Total blocks.
|
||||
|
||||
readers := make([]io.ReadCloser, len(quorumDisks))
|
||||
readFileError := 0
|
||||
for _, quorumDisk := range quorumDisks {
|
||||
erasurePart := slashpath.Join(path, fmt.Sprintf("part.%d", quorumDisk.index))
|
||||
var erasuredPartReader io.ReadCloser
|
||||
if erasuredPartReader, err = quorumDisk.disk.ReadFile(volume, erasurePart, offset); err != nil {
|
||||
// We can safely allow ReadFile errors up to len(quorumDisks) - xl.readQuorum
|
||||
// otherwise return failure
|
||||
if readFileError < len(quorumDisks)-xl.readQuorum {
|
||||
// Set the reader to 'nil' to be able to reconstruct later.
|
||||
readers[quorumDisk.index] = nil
|
||||
readFileError++
|
||||
continue
|
||||
}
|
||||
// Control reaches here we do not have quorum
|
||||
// anymore. Close all the readers.
|
||||
for _, reader := range readers {
|
||||
if reader != nil {
|
||||
reader.Close()
|
||||
}
|
||||
}
|
||||
return nil, errReadQuorum
|
||||
readers := make([]io.ReadCloser, len(xl.storageDisks))
|
||||
for index, disk := range quorumDisks {
|
||||
if disk == nil {
|
||||
continue
|
||||
}
|
||||
erasurePart := slashpath.Join(path, fmt.Sprintf("part.%d", index))
|
||||
// If disk.ReadFile returns error and we don't have read quorum it will be taken care as
|
||||
// ReedSolomon.Reconstruct() will fail later.
|
||||
var reader io.ReadCloser
|
||||
if reader, err = disk.ReadFile(volume, erasurePart, offset); err == nil {
|
||||
readers[index] = reader
|
||||
}
|
||||
readers[quorumDisk.index] = erasuredPartReader
|
||||
}
|
||||
|
||||
// Initialize pipe.
|
||||
@@ -194,19 +154,17 @@ func (xl XL) ReadFile(volume, path string, offset int64) (io.ReadCloser, error)
|
||||
}
|
||||
// Calculate the current encoded block size.
|
||||
curEncBlockSize := getEncodedBlockLen(curBlockSize, xl.DataBlocks)
|
||||
enBlocks := make([][]byte, totalBlocks)
|
||||
enBlocks := make([][]byte, len(xl.storageDisks))
|
||||
// Loop through all readers and read.
|
||||
for index, reader := range readers {
|
||||
if reader == nil {
|
||||
// One of files missing, save it for reconstruction.
|
||||
enBlocks[index] = nil
|
||||
continue
|
||||
}
|
||||
// Initialize shard slice and fill the data from each parts.
|
||||
enBlocks[index] = make([]byte, curEncBlockSize)
|
||||
if reader == nil {
|
||||
continue
|
||||
}
|
||||
_, err = io.ReadFull(reader, enBlocks[index])
|
||||
if err != nil && err != io.ErrUnexpectedEOF {
|
||||
enBlocks[index] = nil
|
||||
readers[index] = nil
|
||||
}
|
||||
}
|
||||
|
||||
@@ -229,6 +187,12 @@ func (xl XL) ReadFile(volume, path string, offset int64) (io.ReadCloser, error)
|
||||
|
||||
// Verification failed, blocks require reconstruction.
|
||||
if !ok {
|
||||
for index, reader := range readers {
|
||||
if reader == nil {
|
||||
// Reconstruct expects missing blocks to be nil.
|
||||
enBlocks[index] = nil
|
||||
}
|
||||
}
|
||||
err = xl.ReedSolomon.Reconstruct(enBlocks)
|
||||
if err != nil {
|
||||
pipeWriter.CloseWithError(err)
|
||||
@@ -264,6 +228,9 @@ func (xl XL) ReadFile(volume, path string, offset int64) (io.ReadCloser, error)
|
||||
|
||||
// Cleanly close all the underlying data readers.
|
||||
for _, reader := range readers {
|
||||
if reader == nil {
|
||||
continue
|
||||
}
|
||||
reader.Close()
|
||||
}
|
||||
}()
|
||||
|
||||
Reference in New Issue
Block a user