OvmfPkg/VirtioFsDxe: add a shared wrapper for FUSE_FSYNC / FUSE_FSYNCDIR

The FUSE_FSYNC and FUSE_FSYNCDIR commands only differ in the opcode. Add a
common function for wrapping both.

Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3097
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20201216211125.19496-14-lersek@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>

OvmfPkg/Include/IndustryStandard/VirtioFs.h

@@ -87,9 +87,11 @@ typedef struct {
 typedef enum {
   VirtioFsFuseOpForget      =  2,
   VirtioFsFuseOpRelease     = 18,
+  VirtioFsFuseOpFsync       = 20,
   VirtioFsFuseOpInit        = 26,
   VirtioFsFuseOpOpenDir     = 27,
   VirtioFsFuseOpReleaseDir  = 29,
+  VirtioFsFuseOpFsyncDir    = 30,
 } VIRTIO_FS_FUSE_OPCODE;
 
 #pragma pack (1)
@@ -130,6 +132,15 @@ typedef struct {
   UINT64 LockOwner;
 } VIRTIO_FS_FUSE_RELEASE_REQUEST;
 
+//
+// Header for VirtioFsFuseOpFsync and VirtioFsFuseOpFsyncDir.
+//
+typedef struct {
+  UINT64 FileHandle;
+  UINT32 FsyncFlags;
+  UINT32 Padding;
+} VIRTIO_FS_FUSE_FSYNC_REQUEST;
+
 //
 // Headers for VirtioFsFuseOpInit.
 //