From 0153f96a20a42202cae3fbf0a815c1076a0df40b Mon Sep 17 00:00:00 2001
From: Harshavardhana <harsha@minio.io>
Date: Tue, 1 Aug 2023 21:52:31 -0700
Subject: [PATCH] add deadlines for readMetadata() in listing (#17776)

Bonus: also skip spending time looking for xl.json

- Listing()
- Delete()
---
 cmd/metacache-walk.go | 25 ++++++++++++++++---------
 cmd/xl-storage.go     | 41 ++++++++++++++++++++++++++++-------------
 2 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/cmd/metacache-walk.go b/cmd/metacache-walk.go
index 876b7ec49..d43532508 100644
--- a/cmd/metacache-walk.go
+++ b/cmd/metacache-walk.go
@@ -1,4 +1,4 @@
-// Copyright (c) 2015-2021 MinIO, Inc.
+// Copyright (c) 2015-2023 MinIO, Inc.
 //
 // This file is part of MinIO Object Storage stack
 //
@@ -79,6 +79,10 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 		return err
 	}
 
+	s.RLock()
+	legacy := s.formatLegacy
+	s.RUnlock()
+
 	// Use a small block size to start sending quickly
 	w := newMetacacheWriter(wr, 16<<10)
 	w.reuseBlocks = true // We are not sharing results, so reuse buffers.
@@ -114,6 +118,7 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 		metadata, err := s.readMetadata(ctx, pathJoin(volumeDir,
 			opts.BaseDir[:len(opts.BaseDir)-1]+globalDirSuffix,
 			xlStorageFormatFile))
+		diskHealthCheckOK(ctx, err)
 		if err == nil {
 			// if baseDir is already a directory object, consider it
 			// as part of the list call, this is AWS S3 specific
@@ -245,7 +250,7 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 				return nil
 			}
 			// Check legacy.
-			if HasSuffix(entry, xlStorageFormatFileV1) {
+			if HasSuffix(entry, xlStorageFormatFileV1) && legacy {
 				var meta metaCacheEntry
 				meta.metadata, err = xioutil.ReadFile(pathJoinBuf(&sb, volumeDir, current, entry))
 				diskHealthCheckOK(ctx, err)
@@ -331,14 +336,16 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 					return err
 				}
 			case osIsNotExist(err), isSysErrIsDir(err):
-				meta.metadata, err = xioutil.ReadFile(pathJoinBuf(&sb, volumeDir, meta.name, xlStorageFormatFileV1))
-				diskHealthCheckOK(ctx, err)
-				if err == nil {
-					// It was an object
-					if err := send(meta); err != nil {
-						return err
+				if legacy {
+					meta.metadata, err = xioutil.ReadFile(pathJoinBuf(&sb, volumeDir, meta.name, xlStorageFormatFileV1))
+					diskHealthCheckOK(ctx, err)
+					if err == nil {
+						// It was an object
+						if err := send(meta); err != nil {
+							return err
+						}
+						continue
 					}
-					continue
 				}
 
 				// NOT an object, append to stack (with slash)
diff --git a/cmd/xl-storage.go b/cmd/xl-storage.go
index b301e0b1a..06567e1e2 100644
--- a/cmd/xl-storage.go
+++ b/cmd/xl-storage.go
@@ -441,7 +441,12 @@ func (s *xlStorage) readMetadataWithDMTime(ctx context.Context, itemPath string)
 }
 
 func (s *xlStorage) readMetadata(ctx context.Context, itemPath string) ([]byte, error) {
-	buf, _, err := s.readMetadataWithDMTime(ctx, itemPath)
+	var buf []byte
+	err := xioutil.NewDeadlineWorker(diskMaxTimeout).Run(func() error {
+		var rerr error
+		buf, _, rerr = s.readMetadataWithDMTime(ctx, itemPath)
+		return rerr
+	})
 	return buf, err
 }
 
@@ -957,16 +962,21 @@ func (s *xlStorage) deleteVersions(ctx context.Context, volume, path string, fis
 	var legacyJSON bool
 	buf, err := s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFile))
 	if err != nil {
-		if err != errFileNotFound {
+		if !errors.Is(err, errFileNotFound) {
 			return err
 		}
 		metaDataPoolPut(buf) // Never used, return it
 
-		buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
-		if err != nil {
-			return err
+		s.RLock()
+		legacy := s.formatLegacy
+		s.RUnlock()
+		if legacy {
+			buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
+			if err != nil {
+				return err
+			}
+			legacyJSON = true
 		}
-		legacyJSON = true
 	}
 
 	if len(buf) == 0 {
@@ -1099,7 +1109,7 @@ func (s *xlStorage) DeleteVersion(ctx context.Context, volume, path string, fi F
 	var legacyJSON bool
 	buf, err := s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFile))
 	if err != nil {
-		if err != errFileNotFound {
+		if !errors.Is(err, errFileNotFound) {
 			return err
 		}
 		metaDataPoolPut(buf) // Never used, return it
@@ -1108,14 +1118,19 @@ func (s *xlStorage) DeleteVersion(ctx context.Context, volume, path string, fi F
 			return s.WriteMetadata(ctx, volume, path, fi)
 		}
 
-		buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
-		if err != nil {
-			if err == errFileNotFound && fi.VersionID != "" {
-				return errFileVersionNotFound
+		s.RLock()
+		legacy := s.formatLegacy
+		s.RUnlock()
+		if legacy {
+			buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFileV1))
+			if err != nil {
+				if errors.Is(err, errFileNotFound) && fi.VersionID != "" {
+					return errFileVersionNotFound
+				}
+				return err
 			}
-			return err
+			legacyJSON = true
 		}
-		legacyJSON = true
 	}
 
 	if len(buf) == 0 {