Added EFI_FILE_PROTOCOL Flush() dummy implementation

The ext4 driver implements EFI_FILE_PROTOCOL_REVISION
but was missing the required Flush() function. According to
UEFI Specification v2.10, Section 13.5 (File Protocol),
all protocol functions must be implemented.

Changes:
- Adds minimal Flush() function implementation

Signed-off-by: Pavel Naberezhnev <[email protected]>

Author: stokescat

Ext4Pkg/Ext4Dxe/Ext4Dxe.h

@@ -715,6 +715,27 @@ Ext4WriteFile (
   IN VOID               *Buffer
   );
 
+/**
+  Flushes all modified data associated with a file to a device
+
+  @param[in]      This        A pointer to the EFI_FILE_PROTOCOL instance that is the file
+                              handle to flush data.
+
+  @retval EFI_SUCCESS          The data was flushed.
+  @retval EFI_NO_MEDIA         The device has no medium.
+  @retval EFI_DEVICE_ERROR     The device reported an error.
+  @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
+  @retval EFI_WRITE_PROTECTED  The file or medium is write-protected.
+  @retval EFI_ACCESS_DENIED    The file was opened read only.
+  @retval EFI_VOLUME_FULL      The volume is full.
+
+**/
+EFI_STATUS
+EFIAPI
+Ext4Flush (
+  IN EFI_FILE_PROTOCOL  *This
+  );
+
 /**
   Returns a file's current position.
 

Ext4Pkg/Ext4Dxe/File.c

@@ -555,6 +555,37 @@ Ext4WriteFile (
   return EFI_WRITE_PROTECTED;
 }
 
+/**
+  Flushes all modified data associated with a file to a device
+
+  @param[in]      This        A pointer to the EFI_FILE_PROTOCOL instance that is the file
+                              handle to flush data.
+
+  @retval EFI_SUCCESS          The data was flushed.
+  @retval EFI_NO_MEDIA         The device has no medium.
+  @retval EFI_DEVICE_ERROR     The device reported an error.
+  @retval EFI_VOLUME_CORRUPTED The file system structures are corrupted.
+  @retval EFI_WRITE_PROTECTED  The file or medium is write-protected.
+  @retval EFI_ACCESS_DENIED    The file was opened read only.
+  @retval EFI_VOLUME_FULL      The volume is full.
+
+**/
+EFI_STATUS
+EFIAPI
+Ext4Flush (
+  IN EFI_FILE_PROTOCOL  *This
+  )
+{
+  EXT4_FILE  *File;
+
+  File = EXT4_FILE_FROM_THIS (This);
+  if (!(File->OpenMode & EFI_FILE_MODE_WRITE)) {
+    return EFI_ACCESS_DENIED;
+  }
+
+  return EFI_WRITE_PROTECTED;
+}
+
 /**
   Returns a file's current position.
 

Ext4Pkg/Ext4Dxe/Partition.c

@@ -89,6 +89,7 @@ Ext4SetupFile (
   File->Protocol.GetPosition = Ext4GetPosition;
   File->Protocol.GetInfo     = Ext4GetInfo;
   File->Protocol.SetInfo     = Ext4SetInfo;
+  File->Protocol.Flush       = Ext4Flush;
 
   File->Partition = Partition;
 }