feat(usb_mass_storage): mount as disk

internal/usbgadget/config.go

@@ -137,6 +137,26 @@ func (u *UsbGadget) GetPath(itemKey string) (string, error) {
 	return joinPath(u.kvmGadgetPath, item.path), nil
 }
 
+func (u *UsbGadget) OverrideGadgetConfig(itemKey string, itemAttr string, value string) (error, bool) {
+	u.configLock.Lock()
+	defer u.configLock.Unlock()
+
+	// get it as a pointer
+	_, ok := u.configMap[itemKey]
+	if !ok {
+		return fmt.Errorf("config item %s not found", itemKey), false
+	}
+
+	if u.configMap[itemKey].attrs[itemAttr] == value {
+		return nil, false
+	}
+
+	u.configMap[itemKey].attrs[itemAttr] = value
+	u.log.Info().Str("itemKey", itemKey).Str("itemAttr", itemAttr).Str("value", value).Msg("overriding gadget config")
+
+	return nil, true
+}
+
 func mountConfigFS() error {
 	_, err := os.Stat(gadgetPath)
 	// TODO: check if it's mounted properly

jsonrpc.go

@@ -523,10 +523,12 @@ type RPCHandler struct {
 func rpcSetMassStorageMode(mode string) (string, error) {
 	logger.Info().Str("mode", mode).Msg("Setting mass storage mode")
 	var cdrom bool
-	if mode == "cdrom" {
+	switch mode {
+	case "cdrom":
 		cdrom = true
-	} else if mode != "file" {
+	case "disk":
-		logger.Info().Str("mode", mode).Msg("Invalid mode provided")
+		cdrom = false
+	default:
 		return "", fmt.Errorf("invalid mode: %s", mode)
 	}
 
@@ -544,12 +546,12 @@ func rpcSetMassStorageMode(mode string) (string, error) {
 }
 
 func rpcGetMassStorageMode() (string, error) {
-	cdrom, err := getMassStorageMode()
+	cdrom, err := getMassStorageCDROMEnabled()
 	if err != nil {
 		return "", fmt.Errorf("failed to get mass storage mode: %w", err)
 	}
 
-	mode := "file"
+	mode := "disk"
 	if cdrom {
 		mode = "cdrom"
 	}

ui/src/routes/devices.$id.mount.tsx

@@ -414,7 +414,7 @@ function BrowserFileView({
     if (file?.name.endsWith(".iso")) {
       setUsbMode("CDROM");
     } else if (file?.name.endsWith(".img")) {
-      setUsbMode("CDROM");
+      setUsbMode("Disk");
     }
   };
 
@@ -566,7 +566,7 @@ function UrlView({
     if (url.endsWith(".iso")) {
       setUsbMode("CDROM");
     } else if (url.endsWith(".img")) {
-      setUsbMode("CDROM");
+      setUsbMode("Disk");
     }
   }
 
@@ -773,7 +773,7 @@ function DeviceFileView({
     if (file.name.endsWith(".iso")) {
       setUsbMode("CDROM");
     } else if (file.name.endsWith(".img")) {
-      setUsbMode("CDROM");
+      setUsbMode("Disk");
     }
   }
 
@@ -1579,7 +1579,6 @@ function UsbModeSelector({
             type="radio"
             id="disk"
             name="mountType"
-            disabled
             checked={usbMode === "Disk"}
             onChange={() => setUsbMode("Disk")}
             className="h-3 w-3 border-slate-800/30 bg-white text-blue-700 transition-opacity focus:ring-blue-500 disabled:opacity-30 dark:bg-slate-800"
@@ -1588,9 +1587,6 @@ function UsbModeSelector({
             <span className="text-sm font-medium leading-none text-slate-900 opacity-50 dark:text-white">
               Disk
             </span>
-            <div className="text-[10px] text-slate-500 dark:text-slate-400">
-              Coming soon
-            </div>
           </div>
         </label>
       </div>

usb_mass_storage.go

@@ -39,18 +39,29 @@ func setMassStorageImage(imagePath string) error {
 }
 
 func setMassStorageMode(cdrom bool) error {
-	massStorageFunctionPath, err := gadget.GetPath("mass_storage_lun0")
+	if gadget == nil {
-	if err != nil {
+		return fmt.Errorf("gadget is not initialized")
-		return fmt.Errorf("failed to get mass storage path: %w", err)
 	}
 
 	mode := "0"
 	if cdrom {
 		mode = "1"
 	}
-	if err := writeFile(path.Join(massStorageFunctionPath, "lun.0", "cdrom"), mode); err != nil {
+
-		return fmt.Errorf("failed to set cdrom mode: %w", err)
+	// override the config
+	err, changed := gadget.OverrideGadgetConfig("mass_storage_lun0", "cdrom", mode)
+	if err != nil {
+		return fmt.Errorf("failed to override gadget config: %w", err)
 	}
+	if !changed {
+		return nil
+	}
+
+	// apply the changes
+	if err := gadget.UpdateGadgetConfig(); err != nil {
+		return fmt.Errorf("failed to write gadget config: %w", err)
+	}
+
 	return nil
 }
 
@@ -109,7 +120,7 @@ func rpcMountBuiltInImage(filename string) error {
 	return mountImage(imagePath)
 }
 
-func getMassStorageMode() (bool, error) {
+func getMassStorageCDROMEnabled() (bool, error) {
 	massStorageFunctionPath, err := gadget.GetPath("mass_storage_lun0")
 	if err != nil {
 		return false, fmt.Errorf("failed to get mass storage path: %w", err)
@@ -193,6 +204,7 @@ func rpcMountWithHTTP(url string, mode VirtualMediaMode) error {
 		virtualMediaStateMutex.Unlock()
 		return fmt.Errorf("another virtual media is already mounted")
 	}
+	setMassStorageMode(mode == CDROM)
 	httpRangeReader = httpreadat.New(url)
 	n, err := httpRangeReader.Size()
 	if err != nil {
@@ -239,6 +251,7 @@ func rpcMountWithWebRTC(filename string, size int64, mode VirtualMediaMode) erro
 		Size:     size,
 	}
 	virtualMediaStateMutex.Unlock()
+	setMassStorageMode(mode == CDROM)
 	logger.Debug().Interface("currentVirtualMediaState", currentVirtualMediaState).Msg("currentVirtualMediaState")
 	logger.Debug().Msg("Starting nbd device")
 	nbdDevice = NewNBDDevice()
@@ -270,6 +283,8 @@ func rpcMountWithStorage(filename string, mode VirtualMediaMode) error {
 		return fmt.Errorf("another virtual media is already mounted")
 	}
 
+	setMassStorageMode(mode == CDROM)
+
 	fullPath := filepath.Join(imagesFolder, filename)
 	fileInfo, err := os.Stat(fullPath)
 	if err != nil {