ui: ozone: drm: synchronize mapped dmabuf with read&write

ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.h"
 
 #include <fcntl.h>
 #include <stddef.h>
 #include <sys/mman.h>
 #include <xf86drm.h>
 
 #include "base/memory/ptr_util.h"
 #include "base/process/memory.h"
 #include "base/trace_event/trace_event.h"
 
 #if defined(OS_CHROMEOS)
 // TODO(vignatti): replace the local definitions below with #include
 // <linux/dma-buf.h> once kernel version 4.6 becomes widely used.
 #include <linux/types.h>
 
 struct local_dma_buf_sync {
   __u64 flags;
 };
 
 #define LOCAL_DMA_BUF_SYNC_READ (1 << 0)
 #define LOCAL_DMA_BUF_SYNC_WRITE (2 << 0)
+#define LOCAL_DMA_BUF_SYNC_RW \
+  (LOCAL_DMA_BUF_SYNC_READ | LOCAL_DMA_BUF_SYNC_WRITE)
 #define LOCAL_DMA_BUF_SYNC_START (0 << 2)
 #define LOCAL_DMA_BUF_SYNC_END (1 << 2)
 
 #define LOCAL_DMA_BUF_BASE 'b'
 #define LOCAL_DMA_BUF_IOCTL_SYNC \
   _IOW(LOCAL_DMA_BUF_BASE, 0, struct local_dma_buf_sync)
 #endif
 
 namespace ui {
 
 namespace {
 
 void PrimeSyncStart(int dmabuf_fd) {
   struct local_dma_buf_sync sync_start = {0};
 
-  sync_start.flags = LOCAL_DMA_BUF_SYNC_START | LOCAL_DMA_BUF_SYNC_READ;
+  sync_start.flags = LOCAL_DMA_BUF_SYNC_START | LOCAL_DMA_BUF_SYNC_RW;
   if (drmIoctl(dmabuf_fd, LOCAL_DMA_BUF_IOCTL_SYNC, &sync_start))
     PLOG(ERROR) << "Failed DMA_BUF_SYNC_START";
 }
 
 void PrimeSyncEnd(int dmabuf_fd) {
   struct local_dma_buf_sync sync_end = {0};
 
-  sync_end.flags = LOCAL_DMA_BUF_SYNC_END | LOCAL_DMA_BUF_SYNC_WRITE;
+  sync_end.flags = LOCAL_DMA_BUF_SYNC_END | LOCAL_DMA_BUF_SYNC_RW;
   if (drmIoctl(dmabuf_fd, LOCAL_DMA_BUF_IOCTL_SYNC, &sync_end))
     PLOG(ERROR) << "Failed DMA_BUF_SYNC_END";
 }
 
 }  // namespace
 
 // static
 std::unique_ptr<ClientNativePixmap> ClientNativePixmapDmaBuf::ImportFromDmabuf(
     int dmabuf_fd,
     const gfx::Size& size,
@@ skipping 33 matching lines @@
 void ClientNativePixmapDmaBuf::Unmap() {
   TRACE_EVENT0("drm", "DmaBuf:Unmap");
   PrimeSyncEnd(dmabuf_fd_.get());
 }
 
 void ClientNativePixmapDmaBuf::GetStride(int* stride) const {
   *stride = stride_;
 }
 
 }  // namespace ui