ui/ozone: Flush CPU caches when mapping/unmapping prime pixmap

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

Index: ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc
diff --git a/ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc b/ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc
index 26d123a2a452209637a928aa78f7b07d1d1dd3a9..a7ac8cb5f81308250a664723a26529ba3a22ec10 100644
--- a/ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc
+++ b/ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.cc
@@ -4,7 +4,9 @@
 
 #include "ui/ozone/platform/drm/common/client_native_pixmap_dmabuf.h"
 
+#include <errno.h>
 #include <fcntl.h>
+#include <linux/dma-buf.h>
 #include <stddef.h>
 #include <sys/mman.h>
 #include <xf86drm.h>
@@ -14,6 +16,27 @@
 
 namespace ui {
 
+namespace {
+
+void PrimeSyncStart(int dmabuf_fd) {
+  struct dma_buf_sync sync_start;
+
+  memset(&sync_start, 0, sizeof(sync_start));

[dshwang, 2016/03/29 13:23:40]

we can change it to c++ style.
struct dma_buf_sync sync_start = {0};

and then memset is not needed.

[vignatti (out of this project), 2016/03/29 21:08:30]

Done.

+  sync_start.flags = DMA_BUF_SYNC_START | DMA_BUF_SYNC_READ;
+  if (drmIoctl(dmabuf_fd, DMA_BUF_IOCTL_SYNC, &sync_start))
+    LOG(ERROR) << "fail to sync start dma buf fd, errno: " << errno;
+}
+
+void PrimeSyncEnd(int dmabuf_fd) {
+  struct dma_buf_sync sync_end;
+
+  memset(&sync_end, 0, sizeof(sync_end));
+  sync_end.flags = DMA_BUF_SYNC_END | DMA_BUF_SYNC_WRITE;
+  if (drmIoctl(dmabuf_fd, DMA_BUF_IOCTL_SYNC, &sync_end))
+    LOG(ERROR) << "fail to sync end dma buf fd, errno " << errno;
+}
+}
+
 // static
 scoped_ptr<ClientNativePixmap> ClientNativePixmapDmaBuf::ImportFromDmabuf(
     int dmabuf_fd,
@@ -26,7 +49,7 @@ scoped_ptr<ClientNativePixmap> ClientNativePixmapDmaBuf::ImportFromDmabuf(
 ClientNativePixmapDmaBuf::ClientNativePixmapDmaBuf(int dmabuf_fd,
                                                    const gfx::Size& size,
                                                    int stride)
-    : size_(size), stride_(stride) {
+    : dmabuf_fd_(dmabuf_fd), size_(size), stride_(stride) {
   TRACE_EVENT0("drm", "ClientNativePixmapDmaBuf");
   size_t map_size = stride_ * size_.height();
   data_ = mmap(nullptr, map_size, (PROT_READ | PROT_WRITE), MAP_SHARED,
@@ -36,16 +59,23 @@ ClientNativePixmapDmaBuf::ClientNativePixmapDmaBuf(int dmabuf_fd,
 
 ClientNativePixmapDmaBuf::~ClientNativePixmapDmaBuf() {
   TRACE_EVENT0("drm", "~ClientNativePixmapDmaBuf");
+  close(dmabuf_fd_);
+
   size_t size = stride_ * size_.height();
   int ret = munmap(data_, size);
   DCHECK(!ret);
 }
 
 void* ClientNativePixmapDmaBuf::Map() {
+  TRACE_EVENT0("nativepixmap", "DmaBuf:Map");
+  PrimeSyncStart(dmabuf_fd_);
   return data_;
 }
 
-void ClientNativePixmapDmaBuf::Unmap() {}
+void ClientNativePixmapDmaBuf::Unmap() {
+  TRACE_EVENT0("nativepixmap", "DmaBuf:Unmap");
+  PrimeSyncEnd(dmabuf_fd_);
+}
 
 void ClientNativePixmapDmaBuf::GetStride(int* stride) const {
   *stride = stride_;