VDA implementation for Exynos, using V4L2

content/common/gpu/media/exynos_video_decode_accelerator.cc

+// Copyright (c) 2012 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 <dlfcn.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/videodev2.h>
+#include <sys/epoll.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+
+#include "base/bind.h"
+#include "base/message_loop.h"
+#include "base/message_loop_proxy.h"
+#include "base/shared_memory.h"
+#include "content/common/gpu/media/exynos_video_decode_accelerator.h"
+#include "ui/gl/gl_bindings.h"
+#include "ui/gl/gl_context.h"
+#include "ui/gl/gl_context_egl.h"
+#include "ui/gl/gl_surface_egl.h"
+
+namespace content {
+
+#define NOTIFY_ERROR(x)                           \
+  do {                                            \
+    LOG(ERROR) << "calling NotifyError(): " << x; \
+    NotifyError(x);                               \
+  } while (0)
+
+#define EXYNOS_MFC_DEVICE "/dev/mfc-dec"
+#define EXYNOS_GSC_DEVICE "/dev/gsc1"
+#define EXYNOS_MALI_DRIVER "libmali.so"
+
+static void* libmali_handle = NULL;
+static EGLBoolean(*mali_egl_image_get_buffer_ext_phandle)(
+    EGLImageKHR, EGLint*, void*) = NULL;
+static EGLSyncKHR(*egl_create_sync_khr)(
+    EGLDisplay, EGLenum, const EGLint*) = NULL;
+static EGLBoolean(*egl_destroy_sync_khr)(
+    EGLDisplay, EGLSyncKHR) = NULL;
+static EGLint(*egl_client_wait_sync_khr)(
+    EGLDisplay, EGLSyncKHR, EGLint, EGLTimeKHR) = NULL;
+
+ExynosVideoDecodeAccelerator::BitstreamBufferRecord::BitstreamBufferRecord(
+    base::SharedMemory* shm, size_t size, int32 input_id)
+    : shm(shm),
+      size(size),
+      input_id(input_id) {
+}
+
+ExynosVideoDecodeAccelerator::BitstreamBufferRecord::~BitstreamBufferRecord() {
+}
+
+ExynosVideoDecodeAccelerator::MfcInputRecord::MfcInputRecord()
+    : at_device(false),
+      offset(NULL),
+      length(0),
+      bytes_used(0),
+      input_id(-1) {
+}
+
+ExynosVideoDecodeAccelerator::MfcInputRecord::~MfcInputRecord() {
+}
+
+ExynosVideoDecodeAccelerator::MfcOutputRecord::MfcOutputRecord()
+    : at_device(false),
+      input_id(-1) {
+  bytes_used[0] = 0;
+  bytes_used[1] = 0;
+  offset[0] = NULL;
+  offset[1] = NULL;
+  length[0] = 0;
+  length[1] = 0;
+}
+
+ExynosVideoDecodeAccelerator::MfcOutputRecord::~MfcOutputRecord() {
+}
+
+ExynosVideoDecodeAccelerator::GscInputRecord::GscInputRecord()
+    : at_device(false),
+      mfc_output(-1) {
+}
+
+ExynosVideoDecodeAccelerator::GscInputRecord::~GscInputRecord() {
+}
+
+ExynosVideoDecodeAccelerator::GscOutputRecord::GscOutputRecord()
+    : at_device(false),
+      at_client(false),
+      fd(-1),
+      egl_image(EGL_NO_IMAGE_KHR),
+      egl_sync(EGL_NO_SYNC_KHR),
+      picture_id(-1) {
+}
+
+ExynosVideoDecodeAccelerator::GscOutputRecord::~GscOutputRecord() {
+}
+
+ExynosVideoDecodeAccelerator::EGLImageKHRArrayRef::EGLImageKHRArrayRef(
+    EGLDisplay egl_display, EGLImageKHR egl_images[], int egl_image_fds[],
+    int egl_images_count)
+    : egl_display(egl_display),
+      egl_images(egl_images),
+      egl_image_fds(egl_image_fds),
+      egl_images_count(egl_images_count) {
+}
+
+ExynosVideoDecodeAccelerator::EGLImageKHRArrayRef::~EGLImageKHRArrayRef() {
+  DCHECK_EQ(egl_images != NULL, egl_image_fds != NULL);
+  if (egl_images == NULL)
+    return;
+
+  for (int i = 0; i < egl_images_count; ++i) {
+    if (egl_images[i] != EGL_NO_IMAGE_KHR)
+      eglDestroyImageKHR(egl_display, egl_images[i]);
+    if (egl_image_fds[i] != -1)
+      close(egl_image_fds[i]);
+  }
+}
+
+ExynosVideoDecodeAccelerator::EGLSyncKHRRef::EGLSyncKHRRef(
+    EGLDisplay egl_display, EGLSyncKHR egl_sync)
+    : egl_display(egl_display),
+      egl_sync(egl_sync) {
+}
+
+ExynosVideoDecodeAccelerator::EGLSyncKHRRef::~EGLSyncKHRRef() {
+  if (egl_sync != EGL_NO_SYNC_KHR)
+    egl_destroy_sync_khr(egl_display, egl_sync);
+}
+
+ExynosVideoDecodeAccelerator::ExynosVideoDecodeAccelerator(
+    gfx::GLContext* gl_context,
+    Client* client,
+    const base::Callback<bool(void)>& make_context_current)
+    : child_message_loop_proxy_(base::MessageLoopProxy::current()),
+      weak_this_(base::AsWeakPtr(this)),
+      client_ptr_factory_(client),
+      client_(client_ptr_factory_.GetWeakPtr()),
+      decoder_thread_("ExynosDecoderThread"),
+      decoder_state_(kUninitialized),
+      decoder_current_bitstream_buffer_(NULL),
+      decoder_current_input_buffer_(-1),
+      decoder_decode_buffer_tasks_scheduled_(0),
+      decoder_frames_inflight_(0),
+      decoder_frames_at_client_(0),
+      decoder_flush_notify_requested_(false),
+      mfc_fd_(-1),
+      mfc_fd_closer_(&mfc_fd_),
+      mfc_input_streamon_(false),
+      mfc_input_buffer_count_(0),
+      mfc_input_buffer_queued_count_(0),
+      mfc_output_streamon_(false),
+      mfc_output_buffer_count_(0),
+      mfc_output_buffer_pixelformat_(0),
+      gsc_fd_(-1),
+      gsc_fd_closer_(&gsc_fd_),
+      gsc_input_streamon_(false),
+      gsc_input_buffer_count_(0),
+      gsc_output_streamon_(false),
+      gsc_output_buffer_count_(0),
+      gsc_output_buffer_prepared_count_(0),
+      gsc_output_buffer_queued_count_(0),
+      frame_buffer_size_(0, 0),
+      device_poll_thread_("ExynosDevicePollThread"),
+      gl_context_(gl_context),
+      make_context_current_(make_context_current),
+      egl_context_(EGL_NO_CONTEXT),
+      egl_display_(EGL_NO_DISPLAY),
+      video_profile_(media::VIDEO_CODEC_PROFILE_UNKNOWN) {
+}
+
+ExynosVideoDecodeAccelerator::~ExynosVideoDecodeAccelerator() {
+  // These maps have members that should be manually destroyed, e.g. file
+  // descriptors, mmap() segments, etc.
+  DCHECK(mfc_input_buffer_map_.empty());
+  DCHECK(mfc_output_buffer_map_.empty());
+  DCHECK(gsc_input_buffer_map_.empty());
+  DCHECK(gsc_output_buffer_map_.empty());
+}
+
+bool ExynosVideoDecodeAccelerator::Initialize(
+    media::VideoCodecProfile profile) {
+  DVLOG(3) << "Initialize()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK_EQ(decoder_state_, kUninitialized);
+
+  switch (profile) {
+    case media::H264PROFILE_BASELINE:
+      DVLOG(2) << "Initialize(): profile H264PROFILE_BASELINE";
+      break;
+    case media::H264PROFILE_MAIN:
+      DVLOG(2) << "Initialize(): profile H264PROFILE_MAIN";
+      break;
+    case media::H264PROFILE_HIGH:
+      DVLOG(2) << "Initialize(): profile H264PROFILE_HIGH";
+      break;
+    case media::VP8PROFILE_MAIN:
+      DVLOG(2) << "Initialize(): profile VP8PROFILE_MAIN";
+      break;
+    default:
+      DLOG(ERROR) << "Initialize(): unsupported profile=" << profile;
+      return false;
+  };
+  video_profile_ = profile;
+
+  gfx::GLContextEGL* context_egl = static_cast<gfx::GLContextEGL*>(gl_context_);
+  static bool sandbox_initialized = PostSandboxInitialization();
+  if (!sandbox_initialized) {
+    DLOG(ERROR) << "Initialize(): PostSandboxInitialization() failed";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  egl_context_ = reinterpret_cast<EGLContext>(context_egl->GetHandle());
+  if (egl_context_ == EGL_NO_CONTEXT) {
+    DLOG(ERROR) << "Initialize(): could not get EGLContext";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+  egl_display_ = gfx::GLSurfaceEGL::GetHardwareDisplay();
+  if (egl_display_ == EGL_NO_DISPLAY) {
+    DLOG(ERROR) << "Initialize(): could not get EGLDisplay";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  // Open the video devices.
+  DVLOG(2) << "Initialize(): opening MFC device: " << EXYNOS_MFC_DEVICE;
+  errno = 0;
+  mfc_fd_ = open(EXYNOS_MFC_DEVICE, O_RDWR | O_NONBLOCK);
+  if (mfc_fd_ == -1) {
+    DPLOG(ERROR) << "Initialize(): could not open MFC device: "
+                 << EXYNOS_MFC_DEVICE;
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+  DVLOG(2) << "Initialize(): opening GSC device: " << EXYNOS_GSC_DEVICE;
+  errno = 0;
+  gsc_fd_ = open(EXYNOS_GSC_DEVICE, O_RDWR | O_NONBLOCK);
+  if (gsc_fd_ == -1) {
+    DPLOG(ERROR) << "Initialize(): could not open GSC device: "
+                 << EXYNOS_GSC_DEVICE;
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  // Capabilities check.
+  struct v4l2_capability caps;
+  const __u32 kCapsRequired =
+      V4L2_CAP_VIDEO_CAPTURE_MPLANE |
+      V4L2_CAP_VIDEO_OUTPUT_MPLANE |
+      V4L2_CAP_STREAMING;
+  errno = 0;
+  if (ioctl(mfc_fd_, VIDIOC_QUERYCAP, &caps) != 0) {
+    DPLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  } else if ((caps.capabilities & kCapsRequired) != kCapsRequired) {
+    DLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP"
+        ", caps check failed: 0x" << std::hex << caps.capabilities;
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+  errno = 0;
+  if (ioctl(gsc_fd_, VIDIOC_QUERYCAP, &caps) != 0) {
+    DPLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  } else if ((caps.capabilities & kCapsRequired) != kCapsRequired) {
+    DLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP"
+        ", caps check failed: 0x" << std::hex << caps.capabilities;
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  // Some random ioctls that Exynos requires.
+  struct v4l2_control control;
+  memset(&control, 0, sizeof(control));
+  control.id = V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY; // also VP8
+  control.value = 8; // Magic number from Samsung folks.
+  errno = 0;
+  if (ioctl(mfc_fd_, VIDIOC_S_CTRL, &control) != 0) {
+    DPLOG(ERROR) << "Initialize(): ioctl() failed: "
+        "V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  if (!make_context_current_.Run()) {
+    DLOG(ERROR) << "Initialize(): could not make context current";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  if (!CreateMfcInputBuffers()) {
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  // MFC output format has to be setup before streaming starts.
+  struct v4l2_format format;
+  memset(&format, 0, sizeof(format));
+  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  format.fmt.pix_mp.pixelformat = V4L2_PIX_FMT_NV12MT_16X16;
+  if (ioctl(mfc_fd_, VIDIOC_S_FMT, &format) != 0) {
+    DPLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_S_FMT";
+    return false;
+  }
+
+  if (!decoder_thread_.Start()) {
+    DLOG(ERROR) << "Initialize(): decoder thread failed to start";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+
+  // Decoder thread is started, but no tasks can have been posted to it yet.
+  // Safe to touch decoder_state_.
+  decoder_state_ = kInitialized;
+
+  child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+      &Client::NotifyInitializeDone, client_));
+  return true;
+}
+
+void ExynosVideoDecodeAccelerator::Decode(
+    const media::BitstreamBuffer& bitstream_buffer) {
+  DVLOG(1) << "Decode(): input_id=" << bitstream_buffer.id()
+           << ", size=" << bitstream_buffer.size();
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+
+  scoped_ptr<BitstreamBufferRecord> bitstream_record(new BitstreamBufferRecord(
+      new base::SharedMemory(bitstream_buffer.handle(), true),
+      bitstream_buffer.size(), bitstream_buffer.id()));
+  if (!bitstream_record->shm->Map(bitstream_buffer.size())) {
+    DLOG(ERROR) << "Decode(): could not map bitstream_buffer";
+    NOTIFY_ERROR(UNREADABLE_INPUT);
+    return;
+  }
+  DVLOG(3) << "Decode(): mapped to addr=" << bitstream_record->shm->memory();
+
+  // DecodeTask() will take care of running a DecodeBufferTask().
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::DecodeTask, base::Unretained(this),
+      base::Passed(&bitstream_record)));
+}
+
+void ExynosVideoDecodeAccelerator::AssignPictureBuffers(
+    const std::vector<media::PictureBuffer>& buffers) {
+  DVLOG(3) << "AssignPictureBuffers(): buffer_count=" << buffers.size();
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+
+  if (!make_context_current_.Run()) {
+    DLOG(ERROR) << "AssignPictureBuffers(): could not make context current";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+
+  DCHECK_EQ(gsc_output_buffer_count_, static_cast<int>(buffers.size()));
+  scoped_ptr<EGLImageKHRArrayRef> egl_images_ref(
+      new EGLImageKHRArrayRef(
+          egl_display_, new EGLImageKHR[buffers.size()],
+          new int[buffers.size()], buffers.size()));
+  for (int i = 0; i < egl_images_ref->egl_images_count; ++i) {
+    egl_images_ref->egl_images[i] = EGL_NO_IMAGE_KHR;
+    egl_images_ref->egl_image_fds[i] = -1;
+  }
+
+  const static EGLint kImageAttrs[] = {
+    EGL_IMAGE_PRESERVED_KHR, 0,
+    EGL_NONE,
+  };
+  Display* x_display = base::MessagePumpForUI::GetDefaultXDisplay();
+  glActiveTexture(GL_TEXTURE0);
+  for (int i = 0; i < egl_images_ref->egl_images_count; ++i) {
+    // Create the X pixmap and then create an EGLImageKHR from it, so we can
+    // get dma_buf backing.
+    Pixmap pixmap = XCreatePixmap(x_display, RootWindow(x_display, 0),
+        buffers[i].size().width(), buffers[i].size().height(), 32);
+    if (!pixmap) {
+      DLOG(ERROR) << "AssignPictureBuffers(): could not create X pixmap";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    glBindTexture(GL_TEXTURE_2D, buffers[i].texture_id());
+    EGLImageKHR egl_image;
+    egl_image = eglCreateImageKHR(
+        egl_display_, EGL_NO_CONTEXT, EGL_NATIVE_PIXMAP_KHR,
+        (EGLClientBuffer)pixmap, kImageAttrs);
+    // We can free the X pixmap immediately -- according to the
+    // EGL_KHR_image_base spec, the backing storage does not go away until the
+    // last referencing EGLImage is destroyed.
+    XFreePixmap(x_display, pixmap);
+    if (egl_image == EGL_NO_IMAGE_KHR) {
+      DLOG(ERROR) << "AssignPictureBuffers(): could not create EGLImageKHR";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    egl_images_ref->egl_images[i] = egl_image;
+    int fd;
+    if (!mali_egl_image_get_buffer_ext_phandle(
+        egl_images_ref->egl_images[i], NULL, &fd)) {
+      DLOG(ERROR) << "AssignPictureBuffers(): "
+                  << "could not get EGLImageKHR dmabuf fd";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    egl_images_ref->egl_image_fds[i] = fd;
+    glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, egl_image);
+  }
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::AssignPictureBuffersTask,
+      base::Unretained(this), base::Passed(&egl_images_ref)));
+}
+
+void ExynosVideoDecodeAccelerator::ReusePictureBuffer(int32 picture_buffer_id) {
+  DVLOG(3) << "ReusePictureBuffer(): picture_buffer_id=" << picture_buffer_id;
+  // Must be run on child thread, as we'll insert a sync in the EGL context.
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+
+  if (!make_context_current_.Run()) {
+    DLOG(ERROR) << "ReusePictureBuffer(): could not make context current";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+
+  EGLSyncKHR egl_sync;
+  egl_sync = egl_create_sync_khr(egl_display_, EGL_SYNC_FENCE_KHR, NULL);
+  if (egl_sync == EGL_NO_SYNC_KHR) {
+    DLOG(ERROR) << "ReusePictureBuffer(): eglCreateSyncKHR() failed";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+
+  scoped_ptr<EGLSyncKHRRef> egl_sync_ref(new EGLSyncKHRRef(
+      egl_display_, egl_sync));
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::ReusePictureBufferTask,
+      base::Unretained(this), picture_buffer_id, base::Passed(&egl_sync_ref)));
+}
+
+void ExynosVideoDecodeAccelerator::Flush() {
+  DVLOG(3) << "Flush()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::FlushTask, base::Unretained(this)));
+}
+
+void ExynosVideoDecodeAccelerator::Reset() {
+  DVLOG(3) << "Reset()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::ResetTask, base::Unretained(this)));
+}
+
+void ExynosVideoDecodeAccelerator::Destroy() {
+  DVLOG(3) << "Destroy()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+
+  // We're destroying; cancel all callbacks.
+  client_ptr_factory_.InvalidateWeakPtrs();
+
+  // If the decoder thread is running, destroy using posted task.
+  if (decoder_thread_.message_loop_proxy()->PostTask(FROM_HERE, base::Bind(
+        &ExynosVideoDecodeAccelerator::DestroyTask, base::Unretained(this)))) {
+    // DestroyTask() will cause the decoder_thread_ to flush all tasks.
+    decoder_thread_.Stop();
+  } else {
+    // Otherwise, call the destroy task directly.
+    DestroyTask();
+  }
+
+  // Nuke the entire site from orbit -- it's the only way to be sure.
+  if (gsc_fd_ != -1) {
+    DestroyGscInputBuffers();
+    DestroyGscOutputBuffers();
+    close(gsc_fd_);
+    gsc_fd_ = -1;
+  }
+  if (mfc_fd_ != -1) {
+    DestroyMfcInputBuffers();
+    DestroyMfcOutputBuffers();
+    close(mfc_fd_);
+    mfc_fd_ = -1;
+  }
+
+  // Decoder thread is stopped by now; safe to touch decoder_state_.
+  // Set to kError state just in case.
+  decoder_state_ = kError;
+
+  delete this;
+}
+
+// static
+void ExynosVideoDecodeAccelerator::PreSandboxInitialization() {
+  DVLOG(3) << "PreSandboxInitialization()";
+  errno = 0;
+  libmali_handle = dlopen(EXYNOS_MALI_DRIVER, RTLD_LAZY | RTLD_LOCAL);
+  if (libmali_handle == NULL) {
+    DPLOG(ERROR) << "failed to dlopen() " << EXYNOS_MALI_DRIVER;
+  }
+}
+
+// static
+bool ExynosVideoDecodeAccelerator::PostSandboxInitialization() {
+  DVLOG(3) << "PostSandboxInitialization()";
+  if (libmali_handle == NULL) {
+    DLOG(ERROR) << "PostSandboxInitialization(): no " << EXYNOS_MALI_DRIVER
+        " driver handle";
+    return false;
+  }
+
+  errno = 0;
+  mali_egl_image_get_buffer_ext_phandle =
+      reinterpret_cast<EGLBoolean(*)(EGLImageKHR, EGLint*, void*)>(
+          dlsym(libmali_handle, "mali_egl_image_get_buffer_ext_phandle"));
+  if (mali_egl_image_get_buffer_ext_phandle == NULL) {
+    DPLOG(ERROR) << "PostSandboxInitialization(): failed to dlsym()"
+        " mali_egl_image_get_buffer_ext_phandle";
+    return false;
+  }
+
+  errno = 0;
+  egl_create_sync_khr =
+      reinterpret_cast<EGLSyncKHR(*)(EGLDisplay, EGLenum, const EGLint*)>(
+          dlsym(libmali_handle, "eglCreateSyncKHR"));
+  if (egl_create_sync_khr == NULL) {
+    DPLOG(ERROR) << "PostSandboxInitialization(): failed to dlsym()"
+        " eglCreateSyncKHR";
+    return false;
+  }
+
+  errno = 0;
+  egl_destroy_sync_khr =
+      reinterpret_cast<EGLBoolean(*)(EGLDisplay, EGLSyncKHR)>(
+          dlsym(libmali_handle, "eglDestroySyncKHR"));
+  if (egl_destroy_sync_khr == NULL) {
+    DPLOG(ERROR) << "PostSandboxInitialization(): failed to dlsym()"
+        " eglDestroySyncKHR";
+    return false;
+  }
+
+  errno = 0;
+  egl_client_wait_sync_khr =
+      reinterpret_cast<EGLint(*)(EGLDisplay, EGLSyncKHR, EGLint, EGLTimeKHR)>(
+          dlsym(libmali_handle, "eglClientWaitSyncKHR"));
+  if (egl_client_wait_sync_khr == NULL) {
+    DPLOG(ERROR) << "PostSandboxInitialization(): failed to dlsym()"
+        " eglClientWaitSyncKHR";
+    return false;
+  }
+
+  return true;
+}
+
+void ExynosVideoDecodeAccelerator::DecodeTask(
+    scoped_ptr<BitstreamBufferRecord> bitstream_record) {
+  DVLOG(3) << "DecodeTask(): input_id=" << bitstream_record->input_id;
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+
+  if (decoder_state_ == kResetting) {
+    DVLOG(2) << "DecodeTask(): early out: kResetting state";
+    return;
+  } else if (decoder_state_ == kError) {
+    DVLOG(2) << "DecodeTask(): early out: kError state";
+    return;
+  }
+
+  decoder_input_queue_.push_front(
+      linked_ptr<BitstreamBufferRecord>(bitstream_record.release()));
+  decoder_decode_buffer_tasks_scheduled_++;
+  DecodeBufferTask();
+}
+
+void ExynosVideoDecodeAccelerator::DecodeBufferTask() {
+  DVLOG(3) << "DecodeBufferTask()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+
+  decoder_decode_buffer_tasks_scheduled_--;
+
+  if (decoder_state_ == kResetting) {
+    DVLOG(2) << "DecodeBufferTask(): early out: kResetting state";
+    return;
+  } else if (decoder_state_ == kError) {
+    DVLOG(2) << "DecodeBufferTask(): early out: kError state";
+    return;
+  }
+
+  if (decoder_current_bitstream_buffer_ == NULL) {
+    if (decoder_input_queue_.empty()) {
+      // We're waiting for a new buffer -- exit without scheduling a new task.
+      return;
+    }
+    // Setup to use the next buffer.
+    decoder_current_bitstream_buffer_.reset(
+        decoder_input_queue_.back().release());
+    decoder_input_queue_.pop_back();
+    DVLOG(3) << "DecodeBufferTask(): reading input_id="
+             << decoder_current_bitstream_buffer_->input_id
+             << ", addr=" << decoder_current_bitstream_buffer_->shm->memory()
+             << ", size=" << decoder_current_bitstream_buffer_->size;
+  }
+  bool decode_result = false;
+  const void* data = decoder_current_bitstream_buffer_->shm->memory();
+  size_t size = decoder_current_bitstream_buffer_->size;
+  switch (decoder_state_) {
+    case kInitialized:
+    case kAfterReset:
+      decode_result = DecodeBufferInitial(data, size);
+      break;
+    case kDecoding:
+      decode_result = DecodeBufferContinue(data, size);
+      break;
+    default:
+      decoder_state_ = kError;
+      NOTIFY_ERROR(ILLEGAL_STATE);
+      return;
+  }
+  if (decoder_state_ == kError) {
+    // Failed during decode.
+    return;
+  } else if (!decode_result) {
+    // We might not have failed decode completely, but returned false due to
+    // insufficient resources, etc.  Retry this this buffer later; exit without
+    // scheduling another task.
+    return;
+  }
+
+  // Our current bitstream buffer is done; return it.
+  int32 input_id = decoder_current_bitstream_buffer_->input_id;
+  DVLOG(3) << "DecodeBufferTask(): finished input_id=" << input_id;
+  decoder_current_bitstream_buffer_.reset(NULL);
+  child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+      &Client::NotifyEndOfBitstreamBuffer, client_, input_id));
+
+  // If we're behind on tasks, schedule another one.
+  if (decoder_decode_buffer_tasks_scheduled_ <
+      static_cast<int>(decoder_input_queue_.size())) {
+    decoder_decode_buffer_tasks_scheduled_++;
+  }

[sheu, 2012/11/03 01:30:09]

Whoops, didn't mean to delete this.  Uploading new version.

+}
+
+bool ExynosVideoDecodeAccelerator::DecodeBufferInitial(
+    const void* data, size_t size) {
+  DVLOG(3) << "DecodeBufferInitial(): data=" << data << ", size=" << size;
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+  DCHECK_NE(decoder_state_, kDecoding);
+  DCHECK(!device_poll_thread_.IsRunning());
+  // Initial decode.  We haven't been able to get output stream format info yet.
+  // Get it, and start decoding.
+
+  // Copy in and send to HW.
+  if (!AppendToInputFrame(data, size) || !FlushInputFrame())
+    return false;
+
+  // Recycle buffers.
+  DequeueMfc();
+
+  // Check and see if we have format info yet.
+  struct v4l2_format format;
+  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  errno = 0;
+  if (ioctl(mfc_fd_, VIDIOC_G_FMT, &format) != 0) {
+    if (errno == EINVAL) {
+      // We will get EINVAL if we haven't seen sufficient stream to decode the
+      // format.  Return true and go to the next buffer.
+      return true;
+    } else {
+      DPLOG(ERROR) << "DecodeBufferInitial(): ioctl() failed: VIDIOC_G_FMT";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+
+  // Run this initialization only on first startup.
+  if (decoder_state_ == kInitialized) {
+    DVLOG(3) << "DecodeBufferInitial(): running one-time initialization";
+    // Success! Setup our parameters.
+    DCHECK_EQ(format.fmt.pix_mp.num_planes, 2);
+    // We don't handle midstream resizes right now.
+    if (!frame_buffer_size_.IsEmpty() && frame_buffer_size_ !=
+        gfx::Size(format.fmt.pix_mp.width, frame_buffer_size_.height())) {
+      // We don't handle mistream resizes right now.
+      NOTIMPLEMENTED();
+      decoder_state_ = kError;
+      NOTIFY_ERROR(UNREADABLE_INPUT);
+      return false;
+    }
+    frame_buffer_size_.SetSize(
+        format.fmt.pix_mp.width, format.fmt.pix_mp.height);
+    mfc_output_buffer_size_[0] = format.fmt.pix_mp.plane_fmt[0].sizeimage;
+    mfc_output_buffer_size_[1] = format.fmt.pix_mp.plane_fmt[1].sizeimage;
+    mfc_output_buffer_pixelformat_ = format.fmt.pix_mp.pixelformat;
+
+    // Create our other buffers.
+    if (!CreateMfcOutputBuffers() || !CreateGscInputBuffers() ||
+        !CreateGscOutputBuffers()) {
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+
+  // StartDevicePoll will raise the error if there is one.
+  if (!StartDevicePoll()) {
+    return false;
+  }
+
+  decoder_state_ = kDecoding;
+
+  // This buffer contained the header that kicks off decoding of the video
+  // stream.  Return false here so it gets recycled into the next
+  // DecodeBufferContinue() and the start of actual output stream.
+  return false;
+}
+
+bool ExynosVideoDecodeAccelerator::DecodeBufferContinue(
+    const void* data, size_t size) {
+  DVLOG(3) << "DecodeBufferContinue(): data=" << data << ", size=" << size;
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_EQ(decoder_state_, kDecoding);
+
+  // We've already setup our output stream parameters, so just keep on truckin'.
+  return (AppendToInputFrame(data, size) && FlushInputFrame());
+}
+
+bool ExynosVideoDecodeAccelerator::AppendToInputFrame(
+    const void* data, size_t size) {
+  DVLOG(3) << "AppendToInputFrame()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  // We should have started streaming when we created MFC input buffers.
+  DCHECK(mfc_input_streamon_);
+  DCHECK(decoder_state_ == kInitialized || decoder_state_ == kDecoding);
+
+  // Flush if we're too big
+  if (decoder_current_input_buffer_ != -1) {
+    MfcInputRecord& input_record =
+        mfc_input_buffer_map_[decoder_current_input_buffer_];
+    if (input_record.bytes_used + size > input_record.length) {
+      if (!FlushInputFrame())
+        return false;
+      decoder_current_input_buffer_ = -1;
+    }
+  }
+
+  // Try to get an available input buffer
+  if (decoder_current_input_buffer_ == -1) {
+    if (mfc_free_input_buffers_.empty()) {
+      // See if we can get more free buffers from HW
+      DequeueMfc();
+      if (mfc_free_input_buffers_.empty()) {
+        // Nope!
+        DVLOG(2) << "AppendToInputFrame(): stalled for input buffers";
+        return false;
+      }
+    }
+    decoder_current_input_buffer_ = mfc_free_input_buffers_.back();
+    mfc_free_input_buffers_.pop_back();
+    MfcInputRecord& input_record =
+        mfc_input_buffer_map_[decoder_current_input_buffer_];
+    DCHECK_EQ(input_record.bytes_used, 0);
+    DCHECK_EQ(input_record.input_id, -1);
+    DCHECK(decoder_current_bitstream_buffer_ != NULL);
+    input_record.input_id = decoder_current_bitstream_buffer_->input_id;
+  }
+
+  // Copy in to the buffer.
+  MfcInputRecord& input_record =
+      mfc_input_buffer_map_[decoder_current_input_buffer_];
+  if (size > input_record.length - input_record.bytes_used) {
+    LOG(ERROR) << "AppendToInputFrame(): over-size frame, erroring";
+    NOTIFY_ERROR(UNREADABLE_INPUT);
+    return false;
+  }
+  memcpy((char*)input_record.offset + input_record.bytes_used, data, size);
+  input_record.bytes_used += size;
+
+  return true;
+}
+
+bool ExynosVideoDecodeAccelerator::FlushInputFrame() {
+  DVLOG(3) << "FlushInputFrame()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK(decoder_state_ == kInitialized || decoder_state_ == kDecoding);
+  if (decoder_current_input_buffer_ == -1)
+    return true;
+
+  MfcInputRecord& input_record =
+      mfc_input_buffer_map_[decoder_current_input_buffer_];
+  if (input_record.bytes_used == 0)
+    return true;
+
+  // Queue it to MFC.
+  mfc_input_ready_queue_.push_back(decoder_current_input_buffer_);
+  decoder_frames_inflight_++;
+  decoder_current_input_buffer_ = -1;
+  DVLOG(3) << "FlushInputFrame(): submitting input_id="
+           << input_record.input_id;
+  // Kick the MFC once since there's new available input for it.
+  EnqueueMfc();
+
+  return (decoder_state_ != kError);
+}
+
+void ExynosVideoDecodeAccelerator::AssignPictureBuffersTask(
+    scoped_ptr<EGLImageKHRArrayRef> egl_images_ref) {
+  DVLOG(3) << "AssignPictureBuffersTask()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+
+  // We run AssignPictureBuffersTask even if we're in kResetting.
+  if (decoder_state_ == kError) {
+    DVLOG(2) << "AssignPictureBuffersTask(): early out: kError state";
+    return;
+  }
+
+  DCHECK_EQ(egl_images_ref->egl_images_count,
+      static_cast<int>(gsc_output_buffer_map_.size()));
+  for (size_t i = 0; i < gsc_output_buffer_map_.size(); ++i) {
+    // We should be blank right now.
+    GscOutputRecord& output_record = gsc_output_buffer_map_[i];
+    DCHECK_EQ(output_record.fd, -1);
+    DCHECK_EQ(output_record.egl_image, EGL_NO_IMAGE_KHR);
+    DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
+    DCHECK_EQ(output_record.picture_id, -1);
+    output_record.fd = egl_images_ref->egl_image_fds[i];
+    output_record.egl_image = egl_images_ref->egl_images[i];
+    output_record.picture_id = i;
+
+    // Take ownership of the EGLImage and fd.
+    egl_images_ref->egl_images[i] = EGL_NO_IMAGE_KHR;
+    egl_images_ref->egl_image_fds[i] = -1;
+    // And add this buffer to the free list.
+    gsc_free_output_buffers_.push_front(i);
+  }
+
+  // StartDevicePoll will raise the error if there is one.
+  StartDevicePoll();
+}
+
+void ExynosVideoDecodeAccelerator::ServiceDeviceTask() {
+  DVLOG(3) << "ServiceDeviceTask()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+  DCHECK_NE(decoder_state_, kInitialized);
+  DCHECK_NE(decoder_state_, kAfterReset);
+
+  if (decoder_state_ == kResetting) {
+    DVLOG(2) << "ServiceDeviceTask(): early out: kResetting state";
+    return;
+  } else if (decoder_state_ == kError) {
+    DVLOG(2) << "ServiceDeviceTask(): early out: kError state";
+    return;
+  }
+
+  DequeueMfc();
+  DequeueGsc();
+  EnqueueMfc();
+  EnqueueGsc();
+
+  DVLOG(1) << "ServiceDeviceTask(): buffer counts: DEC["
+           << decoder_input_queue_.size() << "->"
+           << mfc_input_ready_queue_.size() << "] => MFC["
+           << mfc_free_input_buffers_.size() << "/"
+           << mfc_input_buffer_count_ << "->"
+           << mfc_free_output_buffers_.size() << "/"
+           << mfc_output_buffer_count_ << "] => "
+           << mfc_output_gsc_input_queue_.size() << " => GSC["
+           << gsc_free_input_buffers_.size() << "/"
+           << gsc_input_buffer_count_ << "->"
+           << gsc_free_output_buffers_.size() << "/"
+           << gsc_output_buffer_count_ << "] => VDA["
+           << decoder_frames_at_client_ << "]";
+
+  // If we're behind on decode, schedule another one.
+  if (decoder_decode_buffer_tasks_scheduled_ <
+      static_cast<int>(decoder_input_queue_.size())) {
+    decoder_decode_buffer_tasks_scheduled_++;
+    decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+        &ExynosVideoDecodeAccelerator::DecodeBufferTask,
+        base::Unretained(this)));
+  }
+}
+
+void ExynosVideoDecodeAccelerator::EnqueueMfc() {
+  DVLOG(3) << "EnqueueMfc()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+
+  // Drain the pipe of completed decode buffers.
+  struct v4l2_buffer qbuf;
+  struct v4l2_plane qbuf_planes[2];
+  while (!mfc_input_ready_queue_.empty()) {
+    // Enqueue the MFC input (VIDEO_OUTPUT) buffer.
+    int buffer = mfc_input_ready_queue_.back();
+    MfcInputRecord& input_record = mfc_input_buffer_map_[buffer];
+    DCHECK(!input_record.at_device);
+    memset(&qbuf, 0, sizeof(qbuf));
+    memset(qbuf_planes, 0, sizeof(qbuf_planes));
+    qbuf.index                 = buffer;
+    qbuf.type                  = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    qbuf.timestamp.tv_sec      = input_record.input_id;
+    qbuf.memory                = V4L2_MEMORY_MMAP;
+    qbuf.m.planes              = qbuf_planes;
+    qbuf.m.planes[0].bytesused = input_record.bytes_used;
+    qbuf.length                = 1;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+      DPLOG(ERROR) << "EnqueueMfc(): ioctl() failed: VIDIOC_QBUF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    input_record.at_device = true;
+    mfc_input_ready_queue_.pop_back();
+    mfc_input_buffer_queued_count_++;
+    DVLOG(3) << "EnqueueMfc(): enqueued input_id=" << input_record.input_id;
+    if (!mfc_input_streamon_) {
+      __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+      errno = 0;
+      if (ioctl(mfc_fd_, VIDIOC_STREAMON, &type) != 0) {
+        DPLOG(ERROR) << "EnqueueMfc(): ioctl() failed: VIDIOC_STREAMON";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+      mfc_input_streamon_ = true;
+    }
+  }
+
+  // Enqueue all the MFC output (VIDEO_CAPTURE) buffers we can.
+  while (!mfc_free_output_buffers_.empty()) {
+    int buffer = mfc_free_output_buffers_.back();
+    MfcOutputRecord& output_record = mfc_output_buffer_map_[buffer];
+    DCHECK(!output_record.at_device);
+    DCHECK_EQ(output_record.input_id, -1);
+    memset(&qbuf, 0, sizeof(qbuf));
+    memset(qbuf_planes, 0, sizeof(qbuf_planes));
+    qbuf.index    = buffer;
+    qbuf.type     = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    qbuf.memory   = V4L2_MEMORY_MMAP;
+    qbuf.m.planes = qbuf_planes;
+    qbuf.length   = 2;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+      DPLOG(ERROR) << "EnqueueMfc(): ioctl() failed: VIDIOC_QBUF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    output_record.at_device = true;
+    mfc_free_output_buffers_.pop_back();
+    if (!mfc_output_streamon_) {
+      __u32 type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+      errno = 0;
+      if (ioctl(mfc_fd_, VIDIOC_STREAMON, &type) != 0) {
+        DPLOG(ERROR) << "EnqueueMfc(): ioctl() failed: VIDIOC_STREAMON";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+      mfc_output_streamon_ = true;
+    }
+  }
+}
+
+void ExynosVideoDecodeAccelerator::DequeueMfc() {
+  DVLOG(3) << "DequeueMfc()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+  DCHECK_NE(decoder_state_, kInitialized);
+
+  // Dequeue completed MFC input (VIDEO_OUTPUT) buffers, and recycle to the free
+  // list.  Note that if we ever run completely dry of input buffers on the MFC
+  // device, epoll() will return EPOLLERR and our DevicePollLoop() will exit
+  // early.  Work around this by never _completely_ draining the MFC input
+  // queue.
+  struct v4l2_buffer dqbuf;
+  struct v4l2_plane planes[2];
+  DCHECK_EQ((decoder_current_input_buffer_ != -1 ? 1 : 0) +
+      static_cast<int>(mfc_input_ready_queue_.size()) +
+      static_cast<int>(mfc_free_input_buffers_.size()) +
+      mfc_input_buffer_queued_count_, mfc_input_buffer_count_);
+  while (mfc_input_buffer_queued_count_ > 1) {
+    memset(&dqbuf, 0, sizeof(dqbuf));
+    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    dqbuf.memory = V4L2_MEMORY_MMAP;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_DQBUF, &dqbuf) != 0) {
+      if (errno == EAGAIN) {
+        // Done all that we could.
+        break;
+      } else if (errno == EINVAL) {
+        // We're not streaming this queue; skip.
+        DVLOG(2) << "DequeueMfc(): VIDEO_OUTPUT not streaming, skipping";
+        break;
+      } else {
+        DPLOG(ERROR) << "DequeueMfc(): ioctl() failed: VIDIOC_DQBUF";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+    }
+    MfcInputRecord& input_record = mfc_input_buffer_map_[dqbuf.index];
+    DCHECK(input_record.at_device);
+    input_record.at_device = false;
+    input_record.bytes_used = 0;
+    input_record.input_id = -1;
+    mfc_free_input_buffers_.push_back(dqbuf.index);
+    mfc_input_buffer_queued_count_--;
+  }
+
+  // Dequeue completed MFC output (VIDEO_CAPTURE) buffers, and queue to the
+  // completed queue.
+  memset(&dqbuf, 0, sizeof(dqbuf));
+  memset(planes, 0, sizeof(planes));
+  dqbuf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  dqbuf.memory = V4L2_MEMORY_MMAP;
+  dqbuf.m.planes = planes;
+  dqbuf.length = 2;
+  errno = 0;
+  while (ioctl(mfc_fd_, VIDIOC_DQBUF, &dqbuf) == 0) {
+    MfcOutputRecord& output_record = mfc_output_buffer_map_[dqbuf.index];
+    DCHECK(output_record.at_device);
+    output_record.at_device = false;
+    output_record.input_id = dqbuf.timestamp.tv_sec;
+    output_record.bytes_used[0] = dqbuf.m.planes[0].bytesused;
+    output_record.bytes_used[1] = dqbuf.m.planes[1].bytesused;
+    DVLOG(3) << "DequeueMfc(): dequeued input_id=" << dqbuf.timestamp.tv_sec;
+    mfc_output_gsc_input_queue_.push_front(dqbuf.index);
+    memset(&dqbuf, 0, sizeof(dqbuf));
+    memset(planes, 0, sizeof(planes));
+    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    dqbuf.memory = V4L2_MEMORY_MMAP;
+    dqbuf.m.planes = planes;
+    dqbuf.length = 2;
+    errno = 0;
+  }
+  if (errno == EINVAL) {
+    // We're not streaming this queue; skip.
+    DVLOG(2) << "DequeueMfc(): VIDEO_CAPTURE not streaming, skipping";
+  } else if (errno != EAGAIN) {
+    DPLOG(ERROR) << "DequeueMfc(): ioctl() failed: VIDIOC_DQBUF";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+}
+
+void ExynosVideoDecodeAccelerator::EnqueueGsc() {
+  DVLOG(3) << "EnqueueGsc()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+  DCHECK_NE(decoder_state_, kInitialized);
+  DCHECK_NE(decoder_state_, kAfterReset);
+
+  // Drain the pipe of completed MFC output buffers.
+  struct v4l2_buffer qbuf;
+  struct v4l2_plane qbuf_planes[2];
+  DCHECK(gsc_output_streamon_);
+  while (!mfc_output_gsc_input_queue_.empty()) {
+    if (gsc_free_input_buffers_.empty())
+      break;
+    // Bug workaround: GSC is liable to race conditions if more than one
+    // buffer is simultaneously queued.
+    if (gsc_output_buffer_queued_count_ > 0)
+      break;
+    if (gsc_output_buffer_prepared_count_ == 0) {
+      // Enqueue a GSC output (VIDEO_CAPTURE) buffer for the incoming GSC input
+      // buffer.
+      if (gsc_free_output_buffers_.empty())
+        break;
+      int buffer = gsc_free_output_buffers_.back();
+      GscOutputRecord& output_record = gsc_output_buffer_map_[buffer];
+      DCHECK(!output_record.at_device);
+      DCHECK(!output_record.at_client);
+      if (output_record.egl_sync != EGL_NO_SYNC_KHR) {
+        // If we have to wait for completion, wait.  Note that
+        // gsc_free_output_buffers_ is a FIFO queue.
+        egl_client_wait_sync_khr(egl_display_, output_record.egl_sync, 0,
+            EGL_FOREVER_KHR);
+        egl_destroy_sync_khr(egl_display_, output_record.egl_sync);
+        output_record.egl_sync = EGL_NO_SYNC_KHR;
+      }
+      memset(&qbuf, 0, sizeof(qbuf));
+      memset(qbuf_planes, 0, sizeof(qbuf_planes));
+      qbuf.index            = buffer;
+      qbuf.type             = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+      qbuf.memory           = V4L2_MEMORY_DMABUF;
+      qbuf.m.planes         = qbuf_planes;
+      qbuf.m.planes[0].m.fd = output_record.fd;
+      qbuf.length           = 1;
+      errno = 0;
+      if (ioctl(gsc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+        DPLOG(ERROR) << "EnqueueGsc(): ioctl() failed: VIDIOC_QBUF";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+      output_record.at_device = true;
+      gsc_free_output_buffers_.pop_back();
+      gsc_output_buffer_prepared_count_++;
+    }
+    // Now enqueue the GSC input (VIDEO_OUTPUT) buffer for the complete MFC
+    // output buffer.  We defer requeuing the MFC output buffer to its free
+    // list, as the GSC input will be using its data.
+    int mfc_buffer, gsc_buffer;
+    mfc_buffer = mfc_output_gsc_input_queue_.back();
+    gsc_buffer = gsc_free_input_buffers_.back();
+    MfcOutputRecord& output_record = mfc_output_buffer_map_[mfc_buffer];
+    DCHECK(!output_record.at_device);
+    GscInputRecord& input_record = gsc_input_buffer_map_[gsc_buffer];
+    DCHECK(!input_record.at_device);
+    DCHECK_EQ(input_record.mfc_output, -1);
+    memset(&qbuf, 0, sizeof(qbuf));
+    memset(qbuf_planes, 0, sizeof(qbuf_planes));
+    qbuf.index                 = gsc_buffer;
+    qbuf.type                  = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    qbuf.timestamp.tv_sec      = output_record.input_id;
+    qbuf.memory                = V4L2_MEMORY_USERPTR;
+    qbuf.m.planes              = qbuf_planes;
+    qbuf.m.planes[0].bytesused = output_record.bytes_used[0];
+    qbuf.m.planes[0].length    = mfc_output_buffer_size_[0];
+    qbuf.m.planes[0].m.userptr = (unsigned long)output_record.offset[0];
+    qbuf.m.planes[1].bytesused = output_record.bytes_used[1];
+    qbuf.m.planes[1].length    = mfc_output_buffer_size_[1];
+    qbuf.m.planes[1].m.userptr = (unsigned long)output_record.offset[1];
+    qbuf.length                = 2;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+      DPLOG(ERROR) << "EnqueueGsc(): ioctl() failed: VIDIOC_QBUF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    input_record.at_device = true;
+    input_record.mfc_output = mfc_buffer;
+    output_record.bytes_used[0] = 0;
+    output_record.bytes_used[1] = 0;
+    mfc_output_gsc_input_queue_.pop_back();
+    gsc_free_input_buffers_.pop_back();
+    gsc_output_buffer_prepared_count_--;
+    gsc_output_buffer_queued_count_++;
+    DVLOG(3) << "EnqueueGsc(): enqueued input_id=" << output_record.input_id;
+    if (!gsc_input_streamon_) {
+      __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+      errno = 0;
+      if (ioctl(gsc_fd_, VIDIOC_STREAMON, &type) != 0) {
+        DPLOG(ERROR) << "EnqueueGsc(): ioctl() failed: VIDIOC_STREAMON";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+      gsc_input_streamon_ = true;
+    }
+  }
+}
+
+void ExynosVideoDecodeAccelerator::DequeueGsc() {
+  DVLOG(3) << "DequeueGsc()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  DCHECK_NE(decoder_state_, kUninitialized);
+  DCHECK_NE(decoder_state_, kInitialized);
+  DCHECK_NE(decoder_state_, kAfterReset);
+
+  // Dequeue completed GSC input (VIDEO_OUTPUT) buffers, and recycle to the free
+  // list.  Also recycle the corresponding MFC output buffers at this time.
+  // Note that if we ever run completely dry of input buffers on the GSC device,
+  // epoll() will return EPOLLERR and our DevicePollLoop() will exit early.
+  // Work around this by never _completely_ draining the GSC input queue.
+  struct v4l2_buffer dqbuf;
+  while (gsc_input_buffer_count_ >
+      static_cast<int>(gsc_free_input_buffers_.size()) + 1) {
+    memset(&dqbuf, 0, sizeof(dqbuf));
+    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    dqbuf.memory = V4L2_MEMORY_DMABUF;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_DQBUF, &dqbuf) != 0) {
+      if (errno == EAGAIN) {
+        // Done all that we could.
+        break;
+      } else if (errno == EINVAL) {
+        // We're not streaming this queue; skip.
+        DVLOG(2) << "DequeueGsc(): VIDEO_OUTPUT not streaming, skipping";
+        break;
+      } else {
+        DPLOG(ERROR) << "DequeueGsc(): ioctl() failed: VIDIOC_DQBUF";
+        decoder_state_ = kError;
+        NOTIFY_ERROR(PLATFORM_FAILURE);
+        return;
+      }
+    }
+    GscInputRecord& input_record = gsc_input_buffer_map_[dqbuf.index];
+    DCHECK(input_record.at_device);
+    input_record.at_device = false;
+    mfc_output_buffer_map_[input_record.mfc_output].input_id = -1;
+    mfc_free_output_buffers_.push_back(input_record.mfc_output);
+    input_record.mfc_output = -1;
+    gsc_free_input_buffers_.push_back(dqbuf.index);
+  }
+
+  // Dequeue completed GSC output (VIDEO_CAPTURE) buffers, and send them off to
+  // the client.  Don't recycle to its free list yet -- we can't do that until
+  // ReusePictureBuffer() returns it to us.
+  memset(&dqbuf, 0, sizeof(dqbuf));
+  dqbuf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  dqbuf.memory = V4L2_MEMORY_DMABUF;
+  errno = 0;
+  while (ioctl(gsc_fd_, VIDIOC_DQBUF, &dqbuf) == 0) {
+    GscOutputRecord& output_record = gsc_output_buffer_map_[dqbuf.index];
+    DCHECK(output_record.at_device);
+    DCHECK(!output_record.at_client);
+    DCHECK_EQ(output_record.egl_sync, EGL_NO_SYNC_KHR);
+    output_record.at_device = false;
+    output_record.at_client = true;
+    gsc_output_buffer_queued_count_--;
+    child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+        &Client::PictureReady, client_, media::Picture(
+            output_record.picture_id, dqbuf.timestamp.tv_sec)));
+    decoder_frames_inflight_--;
+    decoder_frames_at_client_++;
+    DVLOG(1) << "DequeueGsc(): dequeued input_id=" << dqbuf.timestamp.tv_sec
+             << " as picture_id=" << output_record.picture_id;
+    if (decoder_frames_inflight_ == 0 && decoder_flush_notify_requested_) {
+      // We were asked for a flush notification, so let's do it.
+      child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+          &Client::NotifyFlushDone, client_));
+    }
+    memset(&dqbuf, 0, sizeof(dqbuf));
+    dqbuf.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    dqbuf.memory = V4L2_MEMORY_DMABUF;
+    errno = 0;
+  }
+  if (errno == EINVAL) {
+    // We're not streaming this queue; skip.
+    DVLOG(2) << "DequeueGsc(): VIDEO_CAPTURE not streaming, skipping";
+  } else if (errno != EAGAIN) {
+    DPLOG(ERROR) << "DequeueGsc(): ioctl() failed: VIDIOC_DQBUF";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+}
+
+void ExynosVideoDecodeAccelerator::ReusePictureBufferTask(
+    int32 picture_buffer_id, scoped_ptr<EGLSyncKHRRef> egl_sync_ref) {
+  DVLOG(3) << "ReusePictureBufferTask(): picture_buffer_id="
+           << picture_buffer_id;
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+
+  // We run ReusePictureBufferTask even if we're in kResetting.
+  if (decoder_state_ == kError) {
+    DVLOG(2) << "ReusePictureBufferTask(): early out: kError state";
+    return;
+  }
+
+  size_t index;
+  for (index = 0; index < gsc_output_buffer_map_.size(); ++index)
+    if (gsc_output_buffer_map_[index].picture_id == picture_buffer_id)
+      break;
+
+  if (index >= gsc_output_buffer_map_.size()) {
+    DLOG(ERROR) << "ReusePictureBufferTask(): picture_buffer_id not found";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(INVALID_ARGUMENT);
+    return;
+  }
+
+  GscOutputRecord& output_record = gsc_output_buffer_map_[index];
+  DCHECK(!output_record.at_device);
+  DCHECK(output_record.at_client);
+  output_record.at_client = false;
+  output_record.egl_sync = egl_sync_ref->egl_sync;
+  gsc_free_output_buffers_.push_front(index);
+  decoder_frames_at_client_--;
+  // Take ownership of the EGLSync.
+  egl_sync_ref->egl_sync = EGL_NO_SYNC_KHR;
+  // We got a buffer back, so kick the GSC.
+  EnqueueGsc();
+}
+
+void ExynosVideoDecodeAccelerator::FlushTask() {
+  DVLOG(3) << "FlushTask()";
+  // Flush the currently-building frame.
+
+  if (decoder_state_ == kResetting) {
+    DVLOG(2) << "FlushTask(): early out: kResetting state";
+    return;
+  } else if (decoder_state_ == kError) {
+    DVLOG(2) << "FlushTask(): early out: kError state";
+    return;
+  }
+
+  FlushInputFrame();
+
+  if (decoder_frames_inflight_ == 0) {
+    // If we don't have anything actually queued, we can notify immediatey.
+    child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+        &Client::NotifyFlushDone, client_));
+  } else {
+    // We'll flag that we want a flush-finished notification, and just return.
+    decoder_flush_notify_requested_ = true;
+  }
+}
+
+void ExynosVideoDecodeAccelerator::ResetTask() {
+  DVLOG(3) << "ResetTask()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+  // We stop streaming, but we _don't_ destroy our buffers.
+  if (!StopDevicePoll())
+    return;
+
+  if (decoder_current_bitstream_buffer_ != NULL) {
+    int input_id;
+    input_id = decoder_current_bitstream_buffer_->input_id;
+    decoder_current_bitstream_buffer_.reset(NULL);
+    child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+        &Client::NotifyEndOfBitstreamBuffer, client_, input_id));
+  }
+  while (!decoder_input_queue_.empty()) {
+    int input_id;
+    scoped_ptr<BitstreamBufferRecord>
+        bitstream_record(decoder_input_queue_.back().release());
+    decoder_input_queue_.pop_back();
+    input_id = bitstream_record->input_id;
+    child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+        &Client::NotifyEndOfBitstreamBuffer, client_, input_id));
+  }
+
+  decoder_current_input_buffer_ = -1;
+  decoder_decode_buffer_tasks_scheduled_ = 0;
+  decoder_frames_inflight_ = 0;
+  decoder_flush_notify_requested_ = false;
+
+  // Mark that we're resetting, then enqueue a ResetDoneTask().  All intervening
+  // jobs will early-out in the kResetting state.
+  decoder_state_ = kResetting;
+  decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+     &ExynosVideoDecodeAccelerator::ResetDoneTask, base::Unretained(this)));
+}
+
+void ExynosVideoDecodeAccelerator::ResetDoneTask() {
+  DVLOG(3) << "ResetDoneTask()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+
+  // Jobs drained, we're finished resetting.
+  DCHECK_EQ(decoder_state_, kResetting);
+  decoder_state_ = kAfterReset;
+  child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+      &Client::NotifyResetDone, client_));
+}
+
+void ExynosVideoDecodeAccelerator::DestroyTask() {
+  DVLOG(3) << "DestroyTask()";
+
+  // DestroyTask() should run regardless of decoder_state_.
+
+  // Stop streaming and the device_poll_thread_.
+  StopDevicePoll();
+
+  decoder_current_bitstream_buffer_.reset(NULL);
+  decoder_current_input_buffer_ = -1;
+  decoder_decode_buffer_tasks_scheduled_ = 0;
+  decoder_frames_inflight_ = 0;
+  decoder_frames_at_client_ = 0;
+  decoder_flush_notify_requested_ = false;
+  decoder_input_queue_.clear();
+
+  // Set our state to kError.  This will cause all subsequent tasks to
+  // early-exit.
+  decoder_state_ = kError;
+}
+
+bool ExynosVideoDecodeAccelerator::StartDevicePoll() {
+  DVLOG(3) << "StartDevicePoll()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+
+  // Early-out if we're already running.
+  if (device_poll_thread_.IsRunning()) {
+    DVLOG(2) << "StartDevicePoll(): early out: "
+             << "device poll thread already running";
+    return true;
+  }
+
+  // At least one of the OUTPUT or CAPTURE queues for each of MFC and GSC must
+  // be in STREAMON state for epoll() not to return EPOLERR.  So:
+  // * for MFC, we'll start the CAPTURE queue
+  // * for GSC, we'll start the CAPTURE queue
+  // STREAMON requires, unfortunately, that we have buffers already queued.
+  // We'll need to have the buffers available to queue.  If they aren't
+  // available yet, this is not an error; for example, GSC output buffers won't
+  // be available until AssignPictureBuffers() is called.
+  if ((!mfc_output_streamon_ && mfc_free_output_buffers_.empty()) ||
+      gsc_free_output_buffers_.empty()) {
+    DVLOG(2) << "StartDevicePoll(): early out: output buffers unavailable";
+    return true;
+  }
+
+  // The MFC output queue may already have been started when we started
+  // enqueuing MFC input buffers.
+  struct v4l2_buffer qbuf;
+  struct v4l2_plane qbuf_planes[2];
+  if (!mfc_output_streamon_) {
+    // Queue and start the MFC CAPTURE queue
+    int buffer;
+    __u32 type;
+    memset(&qbuf, 0, sizeof(qbuf));
+    memset(qbuf_planes, 0, sizeof(qbuf_planes));
+    buffer = mfc_free_output_buffers_.back();
+    MfcOutputRecord& output_record = mfc_output_buffer_map_[buffer];
+    DCHECK(!output_record.at_device);
+    DCHECK_EQ(output_record.input_id, -1);
+    qbuf.index    = buffer;
+    qbuf.type     = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    qbuf.memory   = V4L2_MEMORY_MMAP;
+    qbuf.m.planes = qbuf_planes;
+    qbuf.length   = 2;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+      DPLOG(ERROR) << "StartDevicePoll(): ioctl() failed: VIDIOC_QBUF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+    output_record.at_device = true;
+    mfc_free_output_buffers_.pop_back();
+    type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_STREAMON, &type) != 0) {
+      DPLOG(ERROR) << "StartDevicePoll(): ioctl() failed: VIDIOC_STREAMON";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+    mfc_output_streamon_ = true;
+  }
+
+  // GSC output should not have been started before we received output buffers.
+  DCHECK(!gsc_output_streamon_);
+  {
+    // Queue and start the GSC CAPTURE queue
+    int buffer;
+    __u32 type;
+    memset(&qbuf, 0, sizeof(qbuf));
+    memset(qbuf_planes, 0, sizeof(qbuf_planes));
+    buffer = gsc_free_output_buffers_.back();
+    GscOutputRecord& output_record = gsc_output_buffer_map_[buffer];
+    DCHECK(!output_record.at_device);
+    DCHECK(!output_record.at_client);
+    qbuf.index            = buffer;
+    qbuf.type             = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    qbuf.memory           = V4L2_MEMORY_DMABUF;
+    qbuf.m.planes         = qbuf_planes;
+    qbuf.m.planes[0].m.fd = gsc_output_buffer_map_[buffer].fd;
+    qbuf.length           = 1;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_QBUF, &qbuf) != 0) {
+      DPLOG(ERROR) << "StartDevicePoll(): ioctl() failed: VIDIOC_QBUF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+    output_record.at_device = true;
+    gsc_free_output_buffers_.pop_back();
+    gsc_output_buffer_prepared_count_++;
+    type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_STREAMON, &type) != 0) {
+      DPLOG(ERROR) << "StartDevicePoll(): ioctl() failed: VIDIOC_STREAMON";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+    gsc_output_streamon_ = true;
+  }
+
+  if (!device_poll_thread_.Start()) {
+    DLOG(ERROR) << "StartDevicePoll(): Device thread failed to start";
+    decoder_state_ = kError;
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return false;
+  }
+  device_poll_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+      &ExynosVideoDecodeAccelerator::DevicePollLoop, base::Unretained(this)));
+
+  return true;
+}
+
+bool ExynosVideoDecodeAccelerator::StopDevicePoll() {
+  DVLOG(3) << "StopDevicePoll()";
+  DCHECK_EQ(decoder_thread_.message_loop(), MessageLoop::current());
+
+  // Stop streaming.
+  if (mfc_input_streamon_) {
+    __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_STREAMOFF, &type) != 0) {
+      DPLOG(ERROR) << "StopDevicePoll(): ioctl() failed: VIDIOC_STREAMOFF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+  mfc_input_streamon_ = false;
+  if (mfc_output_streamon_) {
+    __u32 type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    errno = 0;
+    if (ioctl(mfc_fd_, VIDIOC_STREAMOFF, &type) != 0) {
+      DPLOG(ERROR) << "StopDevicePoll(): ioctl() failed: VIDIOC_STREAMOFF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+  mfc_output_streamon_ = false;
+  if (gsc_input_streamon_) {
+    __u32 type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_STREAMOFF, &type) != 0) {
+      DPLOG(ERROR) << "StopDevicePoll(): ioctl() failed: VIDIOC_STREAMOFF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+  gsc_input_streamon_ = false;
+  if (gsc_output_streamon_) {
+    __u32 type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    errno = 0;
+    if (ioctl(gsc_fd_, VIDIOC_STREAMOFF, &type) != 0) {
+      DPLOG(ERROR) << "StopDevicePoll(): ioctl() failed: VIDIOC_STREAMOFF";
+      decoder_state_ = kError;
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return false;
+    }
+  }
+  gsc_output_streamon_ = false;
+
+  // Stopping streaming should cause DevicePollLoop() to exit.  Join the thread.
+  device_poll_thread_.Stop();
+
+  // Reset all our accounting info.
+  mfc_input_ready_queue_.clear();
+  mfc_free_input_buffers_.clear();
+  DCHECK_EQ(mfc_input_buffer_count_,
+      static_cast<int>(mfc_input_buffer_map_.size()));
+  for (size_t i = 0; i < mfc_input_buffer_map_.size(); ++i) {
+    mfc_free_input_buffers_.push_back(i);
+    mfc_input_buffer_map_[i].at_device = false;
+    mfc_input_buffer_map_[i].bytes_used = 0;
+    mfc_input_buffer_map_[i].input_id = -1;
+  }
+  mfc_input_buffer_queued_count_ = 0;
+  mfc_free_output_buffers_.clear();
+  DCHECK_EQ(mfc_output_buffer_count_,
+     static_cast<int>(mfc_output_buffer_map_.size()));
+  for (size_t i = 0; i < mfc_output_buffer_map_.size(); ++i) {
+    mfc_free_output_buffers_.push_back(i);
+    mfc_output_buffer_map_[i].at_device = false;
+    mfc_output_buffer_map_[i].input_id = -1;
+  }
+  mfc_output_gsc_input_queue_.clear();
+  gsc_free_input_buffers_.clear();
+  DCHECK_EQ(gsc_input_buffer_count_,
+      static_cast<int>(gsc_input_buffer_map_.size()));
+  for (size_t i = 0; i < gsc_input_buffer_map_.size(); ++i) {
+    gsc_free_input_buffers_.push_back(i);
+    gsc_input_buffer_map_[i].at_device = false;
+    gsc_input_buffer_map_[i].mfc_output = -1;
+  }
+  gsc_free_output_buffers_.clear();
+  DCHECK_EQ(gsc_output_buffer_count_,
+      static_cast<int>(gsc_output_buffer_map_.size()));
+  for (size_t i = 0; i < gsc_output_buffer_map_.size(); ++i) {
+    // Only mark those free that aren't being held by the VDA.
+    if (!gsc_output_buffer_map_[i].at_client) {
+      gsc_free_output_buffers_.push_back(i);
+      gsc_output_buffer_map_[i].at_device = false;
+    }
+    if (gsc_output_buffer_map_[i].egl_sync != EGL_NO_SYNC_KHR) {
+      egl_destroy_sync_khr(egl_display_, gsc_output_buffer_map_[i].egl_sync);
+      gsc_output_buffer_map_[i].egl_sync = EGL_NO_SYNC_KHR;
+    }
+  }
+  gsc_output_buffer_prepared_count_ = 0;
+  gsc_output_buffer_queued_count_ = 0;
+
+  DVLOG(3) << "StopDevicePoll(): device poll stopped";
+  return true;
+}
+
+void ExynosVideoDecodeAccelerator::DevicePollLoop() {
+  DVLOG(3) << "DevicePollLoop()";
+  DCHECK_EQ(device_poll_thread_.message_loop(), MessageLoop::current());
+  // This routine just polls on the V4L2 devices, and notifies the
+  // decoder_thread_ when processing needs to occur.  The main loop will
+  // terminate when we return an EPOLLERR to epoll() on the device file
+  // descriptors, which should occur when the devices are sent VIDIOC_STREAMOFF
+  // on their queues.
+
+  int ret;
+  int epoll_fd = -1;
+  file_util::ScopedFD epoll_fd_closer(&epoll_fd);
+  struct epoll_event event;
+  errno = 0;
+  epoll_fd = epoll_create(2);
+  if (epoll_fd == -1) {
+    DPLOG(ERROR) << "DevicePollLoop(): epoll() failed";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+  event.events = EPOLLIN | EPOLLOUT | EPOLLERR | EPOLLET;
+  event.data.fd = mfc_fd_;
+  errno = 0;
+  ret = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, mfc_fd_, &event);
+  if (ret != 0) {
+    DPLOG(ERROR) << "DevicePollLoop(): epoll_ctl() failed";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+  event.events = EPOLLIN | EPOLLOUT | EPOLLERR | EPOLLET;
+  event.data.fd = gsc_fd_;
+  errno = 0;
+  ret = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, gsc_fd_, &event);
+  if (ret != 0) {
+    DPLOG(ERROR) << "DevicePollLoop(): epoll_ctl() failed";
+    NOTIFY_ERROR(PLATFORM_FAILURE);
+    return;
+  }
+
+  for (;;) {
+    // We epoll() and wait for more interesting things to happen.
+    // If we get a VIDIOC_STREAMOFF to the device, epoll() will return EPOLLERR,
+    // and we know to exit the loop that way.
+    DVLOG(3) << "DevicePollLoop(): epoll()";
+    struct epoll_event event;
+    do {
+      errno = 0;
+      ret = epoll_wait(epoll_fd, &event, 1, -1);
+    } while (ret < 1 && errno == EINTR);
+    if (ret == -1) {
+      DPLOG(ERROR) << "DevicePollLoop(): epoll_wait() failed";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    if (event.data.fd != mfc_fd_ && event.data.fd != gsc_fd_) {
+      DLOG(ERROR) << "DevicePollLoop(): epoll() returned unknown fd";
+      NOTIFY_ERROR(PLATFORM_FAILURE);
+      return;
+    }
+    if ((event.events & EPOLLERR) != 0) {
+      DVLOG(2) << "DevicePollLoop(): epoll() returned EPOLERR for "
+               << (event.data.fd == mfc_fd_ ? "mfc_fd_" : "gsc_fd_");
+      // Not necessarily an error.
+      return;
+    }
+    decoder_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
+        &ExynosVideoDecodeAccelerator::ServiceDeviceTask,
+        base::Unretained(this)));
+  }
+}
+
+void ExynosVideoDecodeAccelerator::NotifyError(Error error) {
+  DVLOG(2) << "NotifyError()";
+  if (child_message_loop_proxy_ != base::MessageLoopProxy::current()) {
+    child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+        &ExynosVideoDecodeAccelerator::NotifyError, weak_this_, error));
+    return;
+  }
+
+  if (client_) {
+    client_->NotifyError(error);
+    client_ptr_factory_.InvalidateWeakPtrs();
+  }
+}
+
+bool ExynosVideoDecodeAccelerator::CreateMfcInputBuffers() {
+  DVLOG(3) << "CreateMfcInputBuffers()";
+  // We always run this as we prepare to initialize.
+  DCHECK_EQ(decoder_state_, kUninitialized);
+  DCHECK(!mfc_input_streamon_);
+  DCHECK_EQ(mfc_input_buffer_count_, 0);
+
+  __u32 pixelformat = 0;
+  if (video_profile_ >= media::H264PROFILE_MIN &&
+      video_profile_ <= media::H264PROFILE_MAX) {
+    pixelformat = V4L2_PIX_FMT_H264;
+  } else if (video_profile_ >= media::VP8PROFILE_MIN &&
+             video_profile_ <= media::VP8PROFILE_MAX) {
+    pixelformat = V4L2_PIX_FMT_VP8;
+  } else {
+    NOTREACHED();
+  }
+
+  int ret;
+  struct v4l2_format format;
+  memset(&format, 0, sizeof(format));
+  format.type                              = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  format.fmt.pix_mp.pixelformat            = pixelformat;
+  format.fmt.pix_mp.plane_fmt[0].sizeimage = kMfcInputBufferMaxSize;
+  format.fmt.pix_mp.num_planes             = 1;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_S_FMT, &format);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateMfcInputBuffers(): ioctl() failed: VIDIOC_S_FMT";
+    return false;
+  }
+
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count  = kMfcInputBufferCount;
+  reqbufs.type   = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_MMAP;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateMfcInputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+    return false;
+  }
+  mfc_input_buffer_count_ = reqbufs.count;
+  mfc_input_buffer_map_.resize(mfc_input_buffer_count_);
+  for (int i = 0; i < mfc_input_buffer_count_; ++i) {
+    mfc_free_input_buffers_.push_back(i);
+
+    // Query for the MEMORY_MMAP pointer.
+    struct v4l2_plane planes[1];
+    struct v4l2_buffer buffer;
+    memset(&buffer, 0, sizeof(buffer));
+    memset(planes, 0, sizeof(planes));
+    buffer.index    = i;
+    buffer.type     = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+    buffer.memory   = V4L2_MEMORY_MMAP;
+    buffer.m.planes = planes;
+    buffer.length   = 1;
+    errno = 0;
+    ret = ioctl(mfc_fd_, VIDIOC_QUERYBUF, &buffer);
+    if (ret != 0) {
+      DPLOG(ERROR) << "CreateMfcInputBuffers(): "
+                   << "ioctl() failed: VIDIOC_QUERYBUF";
+      return false;
+    }
+    errno = 0;
+    void* offset = mmap(NULL, buffer.m.planes[0].length,
+        PROT_READ | PROT_WRITE, MAP_SHARED, mfc_fd_,
+        buffer.m.planes[0].m.mem_offset);
+    if (offset == MAP_FAILED) {
+      DPLOG(ERROR) << "CreateMfcInputBuffers(): mmap() failed";
+      return false;
+    }
+    mfc_input_buffer_map_[i].offset = offset;
+    mfc_input_buffer_map_[i].length = buffer.m.planes[0].length;
+  }
+
+  return true;
+}
+
+bool ExynosVideoDecodeAccelerator::CreateMfcOutputBuffers() {
+  DVLOG(3) << "CreateMfcOutputBuffers()";
+  DCHECK_EQ(decoder_state_, kInitialized);
+  DCHECK(!mfc_output_streamon_);
+  DCHECK_EQ(mfc_output_buffer_count_, 0);
+
+  // Number of MFC output buffers we need.
+  int ret;
+  struct v4l2_control ctrl;
+  memset(&ctrl, 0, sizeof(ctrl));
+  ctrl.id = V4L2_CID_MIN_BUFFERS_FOR_CAPTURE;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_G_CTRL, &ctrl);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateMfcOutputBuffers(): ioctl() failed: VIDIOC_G_CTRL";
+    return false;
+  }
+
+  // Output format setup in Initialize().
+
+  // Allocate the output buffers.
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count  = ctrl.value + kMfcOutputBufferExtraCount;
+  reqbufs.type   = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_MMAP;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateMfcOutputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+    return false;
+  }
+
+  // Fill our free-buffers list, and create DMABUFs from them.
+  mfc_output_buffer_count_ = reqbufs.count;
+  mfc_output_buffer_map_.resize(mfc_output_buffer_count_);
+  for (int i = 0; i < mfc_output_buffer_count_; ++i) {
+    mfc_free_output_buffers_.push_back(i);
+
+    // Query for the MEMORY_MMAP pointer.
+    struct v4l2_plane planes[2];
+    struct v4l2_buffer buffer;
+    memset(&buffer, 0, sizeof(buffer));
+    memset(planes, 0, sizeof(planes));
+    buffer.index    = i;
+    buffer.type     = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+    buffer.memory   = V4L2_MEMORY_MMAP;
+    buffer.m.planes = planes;
+    buffer.length   = 2;
+    errno = 0;
+    ret = ioctl(mfc_fd_, VIDIOC_QUERYBUF, &buffer);
+    if (ret != 0) {
+      DPLOG(ERROR) << "CreateMfcOutputBuffers(): "
+                   << "ioctl() failed: VIDIOC_QUERYBUF";
+      return false;
+    }
+
+    // Get their user memory for GSC input.
+    for (int j = 0; j < 2; ++j) {
+      errno = 0;
+      void* offset = mmap(NULL, buffer.m.planes[j].length,
+          PROT_READ | PROT_WRITE, MAP_SHARED, mfc_fd_,
+          buffer.m.planes[j].m.mem_offset);
+      if (offset == MAP_FAILED) {
+        DPLOG(ERROR) << "CreateMfcInputBuffers(): mmap() failed";
+        return false;
+      }
+      mfc_output_buffer_map_[i].offset[j] = offset;
+      mfc_output_buffer_map_[i].length[j] = buffer.m.planes[j].length;
+    }
+  }
+
+  return true;
+}
+
+bool ExynosVideoDecodeAccelerator::CreateGscInputBuffers() {
+  DVLOG(3) << "CreateGscInputBuffers()";
+  DCHECK_EQ(decoder_state_, kInitialized);
+  DCHECK(!gsc_input_streamon_);
+  DCHECK_EQ(gsc_input_buffer_count_, 0);
+
+  int ret;
+  struct v4l2_format format;
+  memset(&format, 0, sizeof(format));
+  format.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  format.fmt.pix_mp.width  = frame_buffer_size_.width();
+  format.fmt.pix_mp.height = frame_buffer_size_.height();
+  DCHECK_EQ(mfc_output_buffer_pixelformat_, V4L2_PIX_FMT_NV12MT_16X16);
+  format.fmt.pix_mp.pixelformat = mfc_output_buffer_pixelformat_;
+  format.fmt.pix_mp.plane_fmt[0].sizeimage = mfc_output_buffer_size_[0];
+  format.fmt.pix_mp.plane_fmt[1].sizeimage = mfc_output_buffer_size_[1];
+  // NV12MT_16X16 is a tiled format for which bytesperline doesn't make too much
+  // sense.  Convention seems to be to assume 8bpp for these tiled formats.
+  format.fmt.pix_mp.plane_fmt[0].bytesperline = frame_buffer_size_.width();
+  format.fmt.pix_mp.plane_fmt[1].bytesperline = frame_buffer_size_.width();
+  format.fmt.pix_mp.num_planes = 2;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_FMT, &format);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_S_FMT";
+    return false;
+  }
+
+  struct v4l2_control control;
+  memset(&control, 0, sizeof(control));
+  control.id = V4L2_CID_ROTATE;
+  control.value = 0;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_CTRL, &control);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_S_CTRL";
+    return false;
+  }
+
+  memset(&control, 0, sizeof(control));
+  control.id = V4L2_CID_HFLIP;
+  control.value = 0;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_CTRL, &control);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_S_CTRL";
+    return false;
+  }
+
+  memset(&control, 0, sizeof(control));
+  control.id = V4L2_CID_VFLIP;
+  control.value = 0;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_CTRL, &control);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_S_CTRL";
+    return false;
+  }
+
+  memset(&control, 0, sizeof(control));
+  control.id = V4L2_CID_GLOBAL_ALPHA;
+  control.value = 255;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_CTRL, &control);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_S_CTRL";
+    return false;
+  }
+
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = kGscOutputBufferCount;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_USERPTR;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0 ) {
+    DPLOG(ERROR) << "CreateGscInputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+    return false;
+  }
+
+  gsc_input_buffer_count_ = reqbufs.count;
+  gsc_input_buffer_map_.resize(gsc_input_buffer_count_);
+  for (int i = 0; i < gsc_input_buffer_count_; ++i) {
+    gsc_free_input_buffers_.push_back(i);
+    gsc_input_buffer_map_[i].mfc_output = -1;
+  }
+
+  return true;
+}
+
+bool ExynosVideoDecodeAccelerator::CreateGscOutputBuffers() {
+  DVLOG(3) << "CreateGscOutputBuffers()";
+  DCHECK_EQ(decoder_state_, kInitialized);
+  DCHECK(!gsc_output_streamon_);
+  DCHECK_EQ(gsc_output_buffer_count_, 0);
+
+  // GSC outputs into the EGLImages we create from the textures we are
+  // assigned.  Assume RGBA8888 format.
+  int ret;
+  struct v4l2_format format;
+  memset(&format, 0, sizeof(format));
+  format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  format.fmt.pix_mp.width  = frame_buffer_size_.width();
+  format.fmt.pix_mp.height = frame_buffer_size_.height();
+  format.fmt.pix_mp.pixelformat = V4L2_PIX_FMT_RGB32;
+  format.fmt.pix_mp.plane_fmt[0].sizeimage =
+      frame_buffer_size_.width() * frame_buffer_size_.height() * 4;
+  format.fmt.pix_mp.plane_fmt[0].bytesperline = frame_buffer_size_.width() * 4;
+  format.fmt.pix_mp.num_planes = 1;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_S_FMT, &format);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscOutputBuffers(): ioctl() failed: VIDIOC_S_FMT";
+    return false;
+  }
+
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = kGscOutputBufferCount;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_DMABUF;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0) {
+    DPLOG(ERROR) << "CreateGscOutputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+    return false;
+  }
+
+  // We don't actually fill in the freelist or the map here.  That happens once
+  // we have actual usable buffers, after AssignPictureBuffers();
+  gsc_output_buffer_count_ = reqbufs.count;
+  gsc_output_buffer_map_.resize(gsc_output_buffer_count_);
+
+  DVLOG(3) << "CreateGscOutputBuffers(): ProvidePictureBuffers(): "
+           << "buffer_count=" << gsc_output_buffer_count_
+           << ", width=" << frame_buffer_size_.width()
+           << ", height=" << frame_buffer_size_.height();
+  child_message_loop_proxy_->PostTask(FROM_HERE, base::Bind(
+      &Client::ProvidePictureBuffers, client_, gsc_output_buffer_count_,
+      gfx::Size(frame_buffer_size_.width(), frame_buffer_size_.height()),
+      GL_TEXTURE_2D));
+
+  return true;
+}
+
+void ExynosVideoDecodeAccelerator::DestroyMfcInputBuffers() {
+  DVLOG(3) << "DestroyMfcInputBuffers()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(!mfc_input_streamon_);
+
+  for (size_t i = 0; i < mfc_input_buffer_map_.size(); ++i) {
+    if (mfc_input_buffer_map_[i].offset != NULL) {
+      munmap(mfc_input_buffer_map_[i].offset,
+          mfc_input_buffer_map_[i].length);
+    }
+  }
+
+  int ret;
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = 0;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_MMAP;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0)
+    DPLOG(ERROR) << "DestroyMfcInputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+
+  mfc_input_buffer_map_.clear();
+  mfc_free_input_buffers_.clear();
+  mfc_input_buffer_count_ = 0;
+}
+
+void ExynosVideoDecodeAccelerator::DestroyMfcOutputBuffers() {
+  DVLOG(3) << "DestroyMfcOutputBuffers()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(!mfc_output_streamon_);
+
+  for (size_t i = 0; i < mfc_output_buffer_map_.size(); ++i) {
+    if (mfc_output_buffer_map_[i].offset[0] != NULL)
+      munmap(mfc_output_buffer_map_[i].offset[0],
+          mfc_output_buffer_map_[i].length[0]);
+    if (mfc_output_buffer_map_[i].offset[1] != NULL)
+      munmap(mfc_output_buffer_map_[i].offset[1],
+          mfc_output_buffer_map_[i].length[1]);
+  }
+
+  int ret;
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = 0;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_MMAP;
+  errno = 0;
+  ret = ioctl(mfc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0)
+    DPLOG(ERROR) << "DestroyMfcOutputBuffers() ioctl() failed: VIDIOC_REQBUFS";
+
+  mfc_output_buffer_map_.clear();
+  mfc_free_output_buffers_.clear();
+  mfc_output_buffer_count_ = 0;
+}
+
+void ExynosVideoDecodeAccelerator::DestroyGscInputBuffers() {
+  DVLOG(3) << "DestroyGscInputBuffers()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(!gsc_input_streamon_);
+
+  int ret;
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = 0;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_DMABUF;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0)
+    DPLOG(ERROR) << "DestroyGscInputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+
+  gsc_input_buffer_map_.clear();
+  gsc_free_input_buffers_.clear();
+  gsc_input_buffer_count_ = 0;
+}
+
+void ExynosVideoDecodeAccelerator::DestroyGscOutputBuffers() {
+  DVLOG(3) << "DestroyGscOutputBuffers()";
+  DCHECK(child_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(!gsc_output_streamon_);
+
+  if (gsc_output_buffer_map_.size() != 0) {
+    if (!make_context_current_.Run())
+      DLOG(ERROR) << "DestroyGscOutputBuffers(): "
+                  << "could not make context current";
+
+    size_t i = 0;
+    do {
+      GscOutputRecord& output_record = gsc_output_buffer_map_[i];
+      if (output_record.fd != -1)
+        close(output_record.fd);
+      if (output_record.egl_image != EGL_NO_IMAGE_KHR)
+        eglDestroyImageKHR(egl_display_, output_record.egl_image);
+      if (output_record.egl_sync != EGL_NO_SYNC_KHR)
+        egl_destroy_sync_khr(egl_display_, output_record.egl_sync);
+      if (client_)
+        client_->DismissPictureBuffer(output_record.picture_id);
+      ++i;
+    } while (i < gsc_output_buffer_map_.size());
+  }
+
+  int ret;
+  struct v4l2_requestbuffers reqbufs;
+  memset(&reqbufs, 0, sizeof(reqbufs));
+  reqbufs.count = 0;
+  reqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+  reqbufs.memory = V4L2_MEMORY_DMABUF;
+  errno = 0;
+  ret = ioctl(gsc_fd_, VIDIOC_REQBUFS, &reqbufs);
+  if (ret != 0)
+    DPLOG(ERROR) << "DestroyGscOutputBuffers(): ioctl() failed: VIDIOC_REQBUFS";
+
+  gsc_output_buffer_map_.clear();
+  gsc_free_output_buffers_.clear();
+  gsc_output_buffer_count_ = 0;
+}
+
+}  // namespace content