fix: deleting objects was not working after upgrades (#13242)

DeleteObject() on existing objects before `xl.json` to
`xl.meta` change were not working, not sure when this
regression was added. This PR fixes this properly.

Also this PR ensures that we perform rename of xl.json
to xl.meta only during "write" phase of the call i.e
either during Healing or PutObject() overwrites.

Also handles few other scenarios during migration where
`backendEncryptedFile` was missing deleteConfig() will
fail with `configNotFound` this case was not ignored,
which can lead to failure during upgrades.

cmd/config-common.go

@@ -57,7 +57,9 @@ type objectDeleter interface {
 }
 
 func deleteConfig(ctx context.Context, objAPI objectDeleter, configFile string) error {
-	_, err := objAPI.DeleteObject(ctx, minioMetaBucket, configFile, ObjectOptions{})
+	_, err := objAPI.DeleteObject(ctx, minioMetaBucket, configFile, ObjectOptions{
+		DeletePrefix: true,
+	})
 	if err != nil && isErrObjectNotFound(err) {
 		return errConfigNotFound
 	}

cmd/config.go

@@ -96,7 +96,9 @@ func listServerConfigHistory(ctx context.Context, objAPI ObjectLayer, withData b
 
 func delServerConfigHistory(ctx context.Context, objAPI ObjectLayer, uuidKV string) error {
 	historyFile := pathJoin(minioConfigHistoryPrefix, uuidKV+kvPrefix)
-	_, err := objAPI.DeleteObject(ctx, minioMetaBucket, historyFile, ObjectOptions{})
+	_, err := objAPI.DeleteObject(ctx, minioMetaBucket, historyFile, ObjectOptions{
+		DeletePrefix: true,
+	})
 	return err
 }
 

cmd/erasure-sets.go

@@ -893,12 +893,16 @@ func (s *erasureSets) GetObjectInfo(ctx context.Context, bucket, object string,
 }
 
 func (s *erasureSets) deletePrefix(ctx context.Context, bucket string, prefix string) error {
+	var wg sync.WaitGroup
+	wg.Add(len(s.sets))
 	for _, s := range s.sets {
-		_, err := s.DeleteObject(ctx, bucket, prefix, ObjectOptions{DeletePrefix: true})
-		if err != nil {
-			return err
-		}
+		go func(s *erasureObjects) {
+			defer wg.Done()
+			// This is a force delete, no reason to throw errors.
+			s.DeleteObject(ctx, bucket, prefix, ObjectOptions{DeletePrefix: true})
+		}(s)
 	}
+	wg.Wait()
 	return nil
 }
 

cmd/xl-storage.go

@@ -857,10 +857,13 @@ func (s *xlStorage) DeleteVersion(ctx context.Context, volume, path string, fi F
 			// Create a new xl.meta with a delete marker in it
 			return s.WriteMetadata(ctx, volume, path, fi)
 		}
-		if fi.VersionID != "" {
-			return errFileVersionNotFound
+		buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
+		if err != nil {
+			if err == errFileNotFound && fi.VersionID != "" {
+				return errFileVersionNotFound
+			}
+			return err
 		}
-		return errFileNotFound
 	}
 
 	if len(buf) == 0 {
@@ -1111,16 +1114,7 @@ func (s *xlStorage) ReadVersion(ctx context.Context, volume, path, versionID str
 
 	if err != nil {
 		if err == errFileNotFound {
-			if err = s.renameLegacyMetadata(volumeDir, path); err != nil {
-				if err == errFileNotFound {
-					if versionID != "" {
-						return fi, errFileVersionNotFound
-					}
-					return fi, errFileNotFound
-				}
-				return fi, err
-			}
-			buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFile))
+			buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
 			if err != nil {
 				if err == errFileNotFound {
 					if versionID != "" {