From 69294cf98aa82f37330bc7fba53bc2c8a29605fd Mon Sep 17 00:00:00 2001
From: Klaus Post <klauspost@gmail.com>
Date: Fri, 1 Dec 2023 16:13:19 -0800
Subject: [PATCH] Disable DMA optimization on windows (#18575)

It appears that Windows can lock up when errors occur. Use regular copy here.
---
 cmd/storage-rest-server.go         | 4 +++-
 internal/http/response-recorder.go | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/cmd/storage-rest-server.go b/cmd/storage-rest-server.go
index e6322804c..dff9a7233 100644
--- a/cmd/storage-rest-server.go
+++ b/cmd/storage-rest-server.go
@@ -29,6 +29,7 @@ import (
 	"net/http"
 	"os/user"
 	"path"
+	"runtime"
 	"runtime/debug"
 	"strconv"
 	"strings"
@@ -641,9 +642,10 @@ func (s *storageRESTServer) ReadFileStreamHandler(w http.ResponseWriter, r *http
 	defer rc.Close()
 
 	rf, ok := w.(io.ReaderFrom)
-	if ok {
+	if ok && runtime.GOOS != "windows" {
 		// Attempt to use splice/sendfile() optimization, A very specific behavior mentioned below is necessary.
 		// See https://github.com/golang/go/blob/f7c5cbb82087c55aa82081e931e0142783700ce8/src/net/sendfile_linux.go#L20
+		// Windows can lock up with this optimization, so we fall back to regular copy.
 		dr, ok := rc.(*xioutil.DeadlineReader)
 		if ok {
 			sr, ok := dr.ReadCloser.(*sendFileReader)
diff --git a/internal/http/response-recorder.go b/internal/http/response-recorder.go
index 72622601a..cb630a483 100644
--- a/internal/http/response-recorder.go
+++ b/internal/http/response-recorder.go
@@ -80,7 +80,9 @@ var ErrNotImplemented = errors.New("not implemented")
 // returns an error if the underlying ResponseWriter does not implement io.ReaderFrom
 func (lrw *ResponseRecorder) ReadFrom(r io.Reader) (int64, error) {
 	if lrw.ReaderFrom != nil {
-		return lrw.ReaderFrom.ReadFrom(r)
+		n, err := lrw.ReaderFrom.ReadFrom(r)
+		lrw.bytesWritten += int(n)
+		return n, err
 	}
 	return 0, ErrNotImplemented
 }