@ -17,54 +17,50 @@
package main
import (
"encoding/json"
"errors"
"fmt"
"io"
slashpath "path"
"strconv"
)
func ( xl XL ) selfHeal ( volume string , path string ) error {
totalBlocks := xl . DataBlocks + xl . ParityBlocks
needsSelfHeal := make ( [ ] bool , totalBlocks )
var metadata = make ( map [ string ] string )
var readers = make ( [ ] io . Reader , totalBlocks )
var writers = make ( [ ] io . WriteCloser , totalBlocks )
for index , disk := range xl . storageDisks {
metadataFile := slashpath . Join ( path , metadataFile )
// Start from the beginning, we are not reading partial metadata files.
offset := int64 ( 0 )
// Acquire a read lock.
readLock := true
xl . lockNS ( volume , path , readLock )
defer xl . unlockNS ( volume , path , readLock )
metadataReader , err := disk . ReadFile ( volume , metadataFile , offset )
if err != nil {
if err != errFileNotFound {
continue
}
// Needs healing if part.json is not found
needsSelfHeal [ index ] = true
continue
}
defer metadataReader . Close ( )
quorumDisks , metadata , doSelfHeal , err := xl . getReadableDisks ( volume , path )
if err != nil {
return err
}
if ! doSelfHeal {
return nil
}
decoder := json . NewDecoder ( metadataReader )
if err = decoder . Decode ( & metadata ) ; err != nil {
// needs healing if parts.json is not parsable
size , err := metadata . GetSize ( )
if err != nil {
return err
}
for index , disk := range quorumDisks {
if disk == nil {
needsSelfHeal [ index ] = true
continue
}
erasurePart := slashpath . Join ( path , fmt . Sprintf ( "part.%d" , index ) )
erasuredPartReader , err := disk . ReadFile ( volume , erasurePart , offset )
if err != nil {
if err == errFileNotFound {
// Needs healing if part file not found
needsSelfHeal [ index ] = true
}
return err
// 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
offset := int64 ( 0 )
if reader , err = xl . storageDisks [ index ] . ReadFile ( volume , erasurePart , offset ) ; err == nil {
readers [ index ] = reader
defer reader . Close ( )
}
readers [ index ] = erasuredPartReader
defer erasuredPartReader . Close ( )
}
// Check if there is atleast one part that needs to be healed.
@ -85,7 +81,6 @@ func (xl XL) selfHeal(volume string, path string) error {
if ! shNeeded {
continue
}
var err error
erasurePart := slashpath . Join ( path , fmt . Sprintf ( "part.%d" , index ) )
writers [ index ] , err = xl . storageDisks [ index ] . CreateFile ( volume , erasurePart )
if err != nil {
@ -94,11 +89,6 @@ func (xl XL) selfHeal(volume string, path string) error {
return err
}
}
size , err := strconv . ParseInt ( metadata [ "file.size" ] , 10 , 64 )
if err != nil {
closeAndRemoveWriters ( writers ... )
return err
}
var totalLeft = size
for totalLeft > 0 {
// Figure out the right blockSize.
@ -188,69 +178,12 @@ func (xl XL) selfHeal(volume string, path string) error {
writers [ index ] . Close ( )
}
// Write part.json where ever healing was done.
var metadataWriters = make ( [ ] io . WriteCloser , len ( xl . storageDisks ) )
for index , shNeeded := range needsSelfHeal {
if ! shNeeded {
continue
}
metadataFile := slashpath . Join ( path , metadataFile )
metadataWriters [ index ] , err = xl . storageDisks [ index ] . CreateFile ( volume , metadataFile )
if err != nil {
closeAndRemoveWriters ( writers ... )
return err
}
}
metadataBytes , err := json . Marshal ( metadata )
if err != nil {
closeAndRemoveWriters ( metadataWriters ... )
return err
}
// Update the quorum metadata after selfheal.
errs := xl . setPartsMetadata ( volume , path , metadata , needsSelfHeal )
for index , shNeeded := range needsSelfHeal {
if ! shNeeded {
continue
}
_ , err = metadataWriters [ index ] . Write ( metadataBytes )
if err != nil {
closeAndRemoveWriters ( metadataWriters ... )
return err
if shNeeded && errs [ index ] != nil {
return errs [ index ]
}
}
// Metadata written for all the healed parts hence Close() so that
// temp files can be committed.
for index := range xl . storageDisks {
if ! needsSelfHeal [ index ] {
continue
}
metadataWriters [ index ] . Close ( )
}
return nil
}
// self heal.
type selfHeal struct {
volume string
path string
errCh chan <- error
}
// selfHealRoutine - starts a go routine and listens on a channel for healing requests.
func ( xl * XL ) selfHealRoutine ( ) {
xl . selfHealCh = make ( chan selfHeal )
// Healing request can be made like this:
// errCh := make(chan error)
// xl.selfHealCh <- selfHeal{"testbucket", "testobject", errCh}
// fmt.Println(<-errCh)
go func ( ) {
for sh := range xl . selfHealCh {
if sh . volume == "" || sh . path == "" {
sh . errCh <- errors . New ( "volume or path can not be empty" )
continue
}
xl . selfHeal ( sh . volume , sh . path )
sh . errCh <- nil
}
} ( )
}
Krishna Srinivas
8 years ago
committed by