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

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

+// Copyright 2015 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/client_native_pixmap_vgem.h"
+
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <xf86drm.h>
+
+#include "base/trace_event/trace_event.h"
+
+#if defined(OZONE_USE_VGEM_MAP)
+#include <vgem_drm.h>
+#endif
+
+namespace ui {
+
+namespace {
+
+// TODO(dshwang): stride depends on driver, so plumb it from gpu process.
+int StrideInBytes(size_t width, gfx::BufferFormat format) {
+  switch (format) {
+    case gfx::BufferFormat::BGRA_8888:
+    case gfx::BufferFormat::RGBX_8888:
+      return width * 4;
+    case gfx::BufferFormat::ATC:
+    case gfx::BufferFormat::ATCIA:
+    case gfx::BufferFormat::DXT1:
+    case gfx::BufferFormat::DXT5:
+    case gfx::BufferFormat::ETC1:
+    case gfx::BufferFormat::R_8:
+    case gfx::BufferFormat::RGBA_4444:
+    case gfx::BufferFormat::RGBA_8888:
+    case gfx::BufferFormat::YUV_420:
+      NOTREACHED();
+      break;
+  }
+  return 0;
+}
+
+}  // namespace
+
+ClientNativePixmapVgem::ClientNativePixmapVgem(base::FileDescriptor handle,
+                                               base::FileDescriptor vgem_handle,
+                                               gfx::Size size,
+                                               gfx::BufferFormat format,
+                                               gfx::BufferUsage usage)
+    : vgem_bo_handle_(0),
+      dma_buf_(handle.fd),
+      vgem_fd_(vgem_handle),
+      size_(size),
+      format_(format),
+      stride_(StrideInBytes(size_.width(), format_)),
+      mmap_ptr_(nullptr) {
+  DCHECK(usage == gfx::BufferUsage::MAP);
+  DCHECK(vgem_fd_.fd >= 0);
+  DCHECK(dma_buf_.get() >= 0);
+}
+
+bool ClientNativePixmapVgem::Initialize() {
+  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;
+}
+
+ClientNativePixmapVgem::~ClientNativePixmapVgem() {
+  if (vgem_bo_handle_) {
+    struct drm_gem_close close;
+    memset(&close, 0, sizeof(close));
+    close.handle = vgem_bo_handle_;
+    int ret = drmIoctl(vgem_fd_.fd, DRM_IOCTL_GEM_CLOSE, &close);
+    if (ret)
+      LOG(ERROR) << "fail to free a vgem buffer. error:" << ret;
+    vgem_bo_handle_ = 0;
+  }
+}
+
+bool ClientNativePixmapVgem::Map(void** data) {
+#if defined(OZONE_USE_VGEM_MAP)
+  TRACE_EVENT0("gpu", "ClientNativePixmapVgem::Map");
+  DCHECK(!mmap_ptr_);
+  DCHECK(vgem_bo_handle_);
+
+  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_VGEM_MODE_MAP_DUMB, &mmap_arg);
+  if (ret) {
+    LOG(ERROR) << "fail to map a vgem buffer. error:" << ret;
+    return false;
+  }
+  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);
+  *data = mmap_ptr_;
+  return true;
+#else
+  NOTREACHED();
+  return false;
+#endif
+}
+
+void ClientNativePixmapVgem::Unmap() {
+#if defined(OZONE_USE_VGEM_MAP)
+  TRACE_EVENT0("gpu", "ClientNativePixmapVgem::Unmap");
+  DCHECK(mmap_ptr_);
+  DCHECK(vgem_bo_handle_);
+
+  size_t size = stride_ * size_.height();
+  int ret = munmap(mmap_ptr_, size);
+  DCHECK(!ret);
+  mmap_ptr_ = nullptr;
+#else
+  NOTREACHED();
+#endif
+}
+void ClientNativePixmapVgem::GetStride(int* stride) const {
+  *stride = stride_;
+}
+
+}  // namespace ui