qemuimgutil: fix "Failed to get \"write\" lock" error

Fix issue 3720

Thanks to pavelanni for providing the fix generated by Claude

Signed-off-by: Akihiro Suda <[email protected]>

Author: AkihiroSuda

pkg/qemuimgutil/qemuimgutil.go

@@ -103,6 +103,35 @@ type InfoFormatSpecificDataVmdkExtent struct {
 }
 
 func convertToRaw(source, dest string) error {
+	// If source == dest, we need to use a temporary file to avoid file locking issues
+	if source == dest {
+		// Get info to check if it's already raw format
+		info, err := getInfo(source)
+		if err != nil {
+			return fmt.Errorf("failed to get info for source disk %q: %w", source, err)
+		}
+		// If already raw, no conversion needed
+		if info.Format == "raw" {
+			return nil
+		}
+
+		// Create temporary file for conversion
+		tempFile := dest + ".lima-qemu-convert.tmp"
+		defer os.Remove(tempFile) // Clean up temp file
+
+		// Convert to temp file first
+		if err := convertToRawHelper(source, tempFile); err != nil {
+			return err
+		}
+
+		// Replace original with converted file
+		return os.Rename(tempFile, dest)
+	}
+
+	return convertToRawHelper(source, dest)
+}
+
+func convertToRawHelper(source, dest string) error {
 	var stdout, stderr bytes.Buffer
 	cmd := exec.Command("qemu-img", "convert", "-O", "raw", source, dest)
 	cmd.Stdout = &stdout