mirror of
https://github.com/minio/minio.git
synced 2024-12-26 07:05:55 -05:00
85 lines
2.5 KiB
Go
85 lines
2.5 KiB
Go
/*
|
|
* Minio Cloud Storage, (C) 2016 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 "encoding/hex"
|
|
|
|
// Heals the erasure coded file. reedsolomon.Reconstruct() is used to reconstruct the missing parts.
|
|
func erasureHealFile(latestDisks []StorageAPI, outDatedDisks []StorageAPI, volume, path, healBucket, healPath string, size int64, blockSize int64, dataBlocks int, parityBlocks int, algo string) (checkSums []string, err error) {
|
|
var offset int64
|
|
remainingSize := size
|
|
|
|
// Hash for bitrot protection.
|
|
hashWriters := newHashWriters(len(outDatedDisks), bitRotAlgo)
|
|
|
|
for remainingSize > 0 {
|
|
curBlockSize := blockSize
|
|
if remainingSize < curBlockSize {
|
|
curBlockSize = remainingSize
|
|
}
|
|
|
|
// Calculate the block size that needs to be read from each disk.
|
|
curEncBlockSize := getChunkSize(curBlockSize, dataBlocks)
|
|
|
|
// Memory for reading data from disks and reconstructing missing data using erasure coding.
|
|
enBlocks := make([][]byte, len(latestDisks))
|
|
|
|
// Read data from the latest disks.
|
|
// FIXME: no need to read from all the disks. dataBlocks+1 is enough.
|
|
for index, disk := range latestDisks {
|
|
if disk == nil {
|
|
continue
|
|
}
|
|
enBlocks[index] = make([]byte, curEncBlockSize)
|
|
_, err := disk.ReadFile(volume, path, offset, enBlocks[index])
|
|
if err != nil {
|
|
enBlocks[index] = nil
|
|
}
|
|
}
|
|
|
|
// Reconstruct missing data.
|
|
err := decodeData(enBlocks, dataBlocks, parityBlocks)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// Write to the healPath file.
|
|
for index, disk := range outDatedDisks {
|
|
if disk == nil {
|
|
continue
|
|
}
|
|
err := disk.AppendFile(healBucket, healPath, enBlocks[index])
|
|
if err != nil {
|
|
return nil, traceError(err)
|
|
}
|
|
hashWriters[index].Write(enBlocks[index])
|
|
}
|
|
remainingSize -= curBlockSize
|
|
offset += curEncBlockSize
|
|
}
|
|
|
|
// Checksums for the bit rot.
|
|
checkSums = make([]string, len(outDatedDisks))
|
|
for index, disk := range outDatedDisks {
|
|
if disk == nil {
|
|
continue
|
|
}
|
|
checkSums[index] = hex.EncodeToString(hashWriters[index].Sum(nil))
|
|
}
|
|
return checkSums, nil
|
|
}
|