ozone: Implement zero/one-copy texture for Ozone GBM.

ui/ozone/platform/drm/gpu/vgem_pixmap.cc

Index: ui/ozone/platform/drm/gpu/vgem_pixmap.cc
diff --git a/ui/ozone/platform/drm/gpu/vgem_pixmap.cc b/ui/ozone/platform/drm/gpu/vgem_pixmap.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e0a85e85a866045273153cd385d92c8474faaf20
--- /dev/null
+++ b/ui/ozone/platform/drm/gpu/vgem_pixmap.cc
@@ -0,0 +1,129 @@
+// Copyright 2014 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/gpu/vgem_pixmap.h"
+
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <xf86drm.h>
+
+#include "base/trace_event/trace_event.h"
+#include "ui/ozone/public/surface_factory_ozone.h"
+
+namespace ui {
+
+namespace {
+
+size_t StrideInBytes(size_t width, SurfaceFactoryOzone::BufferFormat format) {
+  switch (format) {
+    case SurfaceFactoryOzone::BGRA_8888:
+    case SurfaceFactoryOzone::RGBX_8888:
+      return width * 4;
+    case SurfaceFactoryOzone::UNKNOWN:
+      NOTREACHED();
+  }
+  NOTREACHED();
+  return 0;
+}
+
+}  // namespace
+
+VgemPixmap::VgemPixmap(base::FileDescriptor handle,
+                       base::FileDescriptor vgem_handle,
+                       gfx::Size size,
+                       SurfaceFactoryOzone::BufferFormat format,
+                       BufferUsage usage)
+    : vgem_bo_handle_(0),
+      vgem_fd_(vgem_handle),
+      size_(size),
+      format_(format),
+      usage_(usage),
+      stride_(StrideInBytes(size_.width(), format_)),
+      mmap_ptr_(nullptr) {
+  if (usage_ == MAP) {
+    DCHECK(vgem_fd_.fd > 0);
+    DCHECK(handle.fd > 0);
+    dma_buf_.reset(handle.fd);
+  }
+}
+
+bool VgemPixmap::Initialize() {
+  if (usage_ == SCANOUT)
+    return true;
+
+  DCHECK(vgem_fd_.fd);
+  int ret = drmPrimeFDToHandle(vgem_fd_.fd, dma_buf_.get(), &vgem_bo_handle_);
+  if (ret) {
+    LOG(ERROR) << "drmPrimeFDToHandle failed, handle:" << vgem_bo_handle_;
+    return false;
+  }
+  return true;
+}
+
+VgemPixmap::~VgemPixmap() {
+  if (vgem_bo_handle_) {
+    DCHECK_EQ(usage_, MAP);
+    struct drm_mode_destroy_dumb destroy;
+    memset(&destroy, 0, sizeof(destroy));
+    destroy.handle = vgem_bo_handle_;
+    int ret = drmIoctl(vgem_fd_.fd, DRM_IOCTL_MODE_DESTROY_DUMB, &destroy);
+    if (!ret)
+      LOG(ERROR) << "fail to free a vgem buffer. error:" << ret;
+    vgem_bo_handle_ = 0;
+  }
+}
+
+void* VgemPixmap::GetEGLClientBuffer() {
+  return nullptr;
+}
+
+int VgemPixmap::GetDmaBufFd() {
+  return dma_buf_.get();
+}
+
+int VgemPixmap::GetDmaBufPitch() {
+  return stride_;
+}
+
+NativePixmap::BufferUsage VgemPixmap::GetBufferUsage() const {
+  return usage_;
+}
+
+void* VgemPixmap::Map() {
+  TRACE_EVENT0("gpu", "VgemPixmap::Map");
+  DCHECK(!mmap_ptr_);
+  DCHECK(!vgem_bo_handle_);
+  DCHECK_EQ(usage_, SurfaceFactoryOzone::MAP);

[vignatti (out of this project), 2015/06/18 17:00:52]

comparison of two values with different enumeration types. 
s/SurfaceFactoryOzone::MAP/MAP does the needed trick.

[dshwang, 2015/06/25 10:59:56]

Oops, mistake. interestingly, compiler didn't complain. there is some macro dark
magic. Done.

+
+  struct drm_mode_map_dumb mmap_arg;
+  memset(&mmap_arg, 0, sizeof(mmap_arg));
+  mmap_arg.handle = vgem_bo_handle_;
+
+  int ret = drmIoctl(vgem_fd_.fd, DRM_IOCTL_MODE_MAP_DUMB, &mmap_arg);
+  if (ret) {
+    LOG(ERROR) << "fail to map a vgem buffer. error:" << ret;
+    return nullptr;
+  }
+  DCHECK(mmap_arg.offset);
+
+  size_t size = stride_ * size_.height();
+  mmap_ptr_ = mmap(nullptr, size, (PROT_READ | PROT_WRITE), MAP_SHARED,
+                   vgem_fd_.fd, mmap_arg.offset);
+  DCHECK(mmap_ptr_ != MAP_FAILED);
+  return mmap_ptr_;
+}
+
+void VgemPixmap::Unmap() {
+  TRACE_EVENT0("gpu", "VgemPixmap::Unmap");
+  DCHECK(mmap_ptr_);
+  DCHECK(!vgem_bo_handle_);
+  DCHECK_EQ(usage_, SurfaceFactoryOzone::MAP);

[vignatti (out of this project), 2015/06/18 17:00:52]

ditto.

+
+  size_t size = stride_ * size_.height();
+  int ret = munmap(mmap_ptr_, size);
+  DCHECK(!ret);
+  mmap_ptr_ = nullptr;
+}
+
+}  // namespace ui