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path: root/chromium/gpu/ipc/service/gpu_channel.cc
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// 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 "gpu/ipc/service/gpu_channel.h"

#include <utility>

#if defined(OS_WIN)
#include <windows.h>
#endif

#include <algorithm>
#include <set>
#include <vector>

#include "base/atomicops.h"
#include "base/bind.h"
#include "base/command_line.h"
#include "base/containers/circular_deque.h"
#include "base/location.h"
#include "base/numerics/safe_conversions.h"
#include "base/single_thread_task_runner.h"
#include "base/stl_util.h"
#include "base/strings/string_util.h"
#include "base/synchronization/lock.h"
#include "base/threading/thread_checker.h"
#include "base/threading/thread_task_runner_handle.h"
#include "base/timer/timer.h"
#include "base/trace_event/memory_dump_manager.h"
#include "base/trace_event/process_memory_dump.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "gpu/command_buffer/common/mailbox.h"
#include "gpu/command_buffer/service/image_factory.h"
#include "gpu/command_buffer/service/image_manager.h"
#include "gpu/command_buffer/service/mailbox_manager.h"
#include "gpu/command_buffer/service/scheduler.h"
#include "gpu/ipc/common/gpu_messages.h"
#include "gpu/ipc/service/gles2_command_buffer_stub.h"
#include "gpu/ipc/service/gpu_channel_manager.h"
#include "gpu/ipc/service/gpu_channel_manager_delegate.h"
#include "gpu/ipc/service/gpu_memory_buffer_factory.h"
#include "gpu/ipc/service/raster_command_buffer_stub.h"
#include "ipc/ipc_channel.h"
#include "ipc/message_filter.h"
#include "ui/gl/gl_context.h"
#include "ui/gl/gl_image_shared_memory.h"
#include "ui/gl/gl_surface.h"

namespace gpu {
namespace {

CommandBufferId GenerateCommandBufferId(int channel_id, int32_t route_id) {
  return CommandBufferId::FromUnsafeValue(
      (static_cast<uint64_t>(channel_id) << 32) | route_id);
}

}  // anonymous namespace

struct GpuChannelMessage {
  IPC::Message message;
  uint32_t order_number;
  base::TimeTicks time_received;

  GpuChannelMessage(const IPC::Message& msg,
                    uint32_t order_num,
                    base::TimeTicks ts)
      : message(msg), order_number(order_num), time_received(ts) {}

 private:
  DISALLOW_COPY_AND_ASSIGN(GpuChannelMessage);
};

// This filter does the following:
// - handles the Nop message used for verifying sync tokens on the IO thread
// - forwards messages to child message filters
// - posts control and out of order messages to the main thread
// - forwards other messages to the scheduler
class GPU_IPC_SERVICE_EXPORT GpuChannelMessageFilter
    : public IPC::MessageFilter {
 public:
  GpuChannelMessageFilter(
      GpuChannel* gpu_channel,
      Scheduler* scheduler,
      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner);

  // Methods called on main thread.
  void Destroy();

  // Called when scheduler is enabled.
  void AddRoute(int32_t route_id, SequenceId sequence_id);
  void RemoveRoute(int32_t route_id);

  // Methods called on IO thread.
  // IPC::MessageFilter implementation.
  void OnFilterAdded(IPC::Channel* channel) override;
  void OnFilterRemoved() override;
  void OnChannelConnected(int32_t peer_pid) override;
  void OnChannelError() override;
  void OnChannelClosing() override;
  bool OnMessageReceived(const IPC::Message& message) override;

  void AddChannelFilter(scoped_refptr<IPC::MessageFilter> filter);
  void RemoveChannelFilter(scoped_refptr<IPC::MessageFilter> filter);

 private:
  ~GpuChannelMessageFilter() override;

  bool MessageErrorHandler(const IPC::Message& message, const char* error_msg);

  IPC::Channel* ipc_channel_ = nullptr;
  base::ProcessId peer_pid_ = base::kNullProcessId;
  std::vector<scoped_refptr<IPC::MessageFilter>> channel_filters_;

  GpuChannel* gpu_channel_ = nullptr;
  // Map of route id to scheduler sequence id.
  base::flat_map<int32_t, SequenceId> route_sequences_;
  mutable base::Lock gpu_channel_lock_;

  Scheduler* scheduler_;
  scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;

  base::ThreadChecker io_thread_checker_;

  DISALLOW_COPY_AND_ASSIGN(GpuChannelMessageFilter);
};

GpuChannelMessageFilter::GpuChannelMessageFilter(
    GpuChannel* gpu_channel,
    Scheduler* scheduler,
    scoped_refptr<base::SingleThreadTaskRunner> main_task_runner)
    : gpu_channel_(gpu_channel),
      scheduler_(scheduler),
      main_task_runner_(std::move(main_task_runner)) {
  io_thread_checker_.DetachFromThread();
}

GpuChannelMessageFilter::~GpuChannelMessageFilter() {
  DCHECK(!gpu_channel_);
}

void GpuChannelMessageFilter::Destroy() {
  base::AutoLock auto_lock(gpu_channel_lock_);
  gpu_channel_ = nullptr;
}

void GpuChannelMessageFilter::AddRoute(int32_t route_id,
                                       SequenceId sequence_id) {
  base::AutoLock auto_lock(gpu_channel_lock_);
  DCHECK(gpu_channel_);
  DCHECK(scheduler_);
  route_sequences_[route_id] = sequence_id;
}

void GpuChannelMessageFilter::RemoveRoute(int32_t route_id) {
  base::AutoLock auto_lock(gpu_channel_lock_);
  DCHECK(gpu_channel_);
  DCHECK(scheduler_);
  route_sequences_.erase(route_id);
}

void GpuChannelMessageFilter::OnFilterAdded(IPC::Channel* channel) {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  DCHECK(!ipc_channel_);
  ipc_channel_ = channel;
  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_)
    filter->OnFilterAdded(ipc_channel_);
}

void GpuChannelMessageFilter::OnFilterRemoved() {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_)
    filter->OnFilterRemoved();
  ipc_channel_ = nullptr;
  peer_pid_ = base::kNullProcessId;
}

void GpuChannelMessageFilter::OnChannelConnected(int32_t peer_pid) {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  DCHECK(peer_pid_ == base::kNullProcessId);
  peer_pid_ = peer_pid;
  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_)
    filter->OnChannelConnected(peer_pid);
}

void GpuChannelMessageFilter::OnChannelError() {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_)
    filter->OnChannelError();
}

void GpuChannelMessageFilter::OnChannelClosing() {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_)
    filter->OnChannelClosing();
}

void GpuChannelMessageFilter::AddChannelFilter(
    scoped_refptr<IPC::MessageFilter> filter) {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  channel_filters_.push_back(filter);
  if (ipc_channel_)
    filter->OnFilterAdded(ipc_channel_);
  if (peer_pid_ != base::kNullProcessId)
    filter->OnChannelConnected(peer_pid_);
}

void GpuChannelMessageFilter::RemoveChannelFilter(
    scoped_refptr<IPC::MessageFilter> filter) {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  if (ipc_channel_)
    filter->OnFilterRemoved();
  base::Erase(channel_filters_, filter);
}

bool GpuChannelMessageFilter::OnMessageReceived(const IPC::Message& message) {
  DCHECK(io_thread_checker_.CalledOnValidThread());
  DCHECK(ipc_channel_);

  if (message.should_unblock() || message.is_reply())
    return MessageErrorHandler(message, "Unexpected message type");

  if (message.type() == GpuChannelMsg_Nop::ID) {
    IPC::Message* reply = IPC::SyncMessage::GenerateReply(&message);
    ipc_channel_->Send(reply);
    return true;
  }

  for (scoped_refptr<IPC::MessageFilter>& filter : channel_filters_) {
    if (filter->OnMessageReceived(message))
      return true;
  }

  base::AutoLock auto_lock(gpu_channel_lock_);
  if (!gpu_channel_)
    return MessageErrorHandler(message, "Channel destroyed");

  // TODO(sunnyps): Remove the async flush message once the non-scheduler code
  // path is removed.
  if (message.type() == GpuCommandBufferMsg_AsyncFlush::ID)
    return MessageErrorHandler(message, "Invalid flush message");

  std::vector<Scheduler::Task> tasks;

  if (message.type() == GpuChannelMsg_FlushCommandBuffers::ID) {
    GpuChannelMsg_FlushCommandBuffers::Param params;

    if (!GpuChannelMsg_FlushCommandBuffers::Read(&message, &params))
      return MessageErrorHandler(message, "Invalid flush message");

    std::vector<FlushParams> flush_list = std::get<0>(std::move(params));

    for (auto& flush_info : flush_list) {
      GpuCommandBufferMsg_AsyncFlush flush_message(
          flush_info.route_id, flush_info.put_offset, flush_info.flush_id,
          flush_info.snapshot_requested);

      auto it = route_sequences_.find(flush_info.route_id);
      if (it == route_sequences_.end()) {
        DLOG(ERROR) << "Invalid route id in flush list";
        continue;
      }

      tasks.emplace_back(
          it->second /* sequence_id */,
          base::BindOnce(&GpuChannel::HandleMessage, gpu_channel_->AsWeakPtr(),
                         flush_message),
          std::move(flush_info.sync_token_fences));
    }

    scheduler_->ScheduleTasks(std::move(tasks));

  } else if (message.routing_id() == MSG_ROUTING_CONTROL ||
             message.type() == GpuCommandBufferMsg_WaitForTokenInRange::ID ||
             message.type() ==
                 GpuCommandBufferMsg_WaitForGetOffsetInRange::ID) {
    // It's OK to post task that may never run even for sync messages, because
    // if the channel is destroyed, the client Send will fail.
    main_task_runner_->PostTask(FROM_HERE,
                                base::Bind(&GpuChannel::HandleOutOfOrderMessage,
                                           gpu_channel_->AsWeakPtr(), message));
  } else {
    auto it = route_sequences_.find(message.routing_id());
    if (it == route_sequences_.end())
      return MessageErrorHandler(message, "Invalid route id");

    scheduler_->ScheduleTask(
        Scheduler::Task(it->second /* sequence_id */,
                        base::BindOnce(&GpuChannel::HandleMessage,
                                       gpu_channel_->AsWeakPtr(), message),
                        std::vector<SyncToken>()));
  }

  return true;
}

bool GpuChannelMessageFilter::MessageErrorHandler(const IPC::Message& message,
                                                  const char* error_msg) {
  DLOG(ERROR) << error_msg;
  if (message.is_sync()) {
    IPC::Message* reply = IPC::SyncMessage::GenerateReply(&message);
    reply->set_reply_error();
    ipc_channel_->Send(reply);
  }
  return true;
}

// Definitions for constructor and destructor of this interface are needed to
// avoid MSVC LNK2019.
FilteredSender::FilteredSender() = default;

FilteredSender::~FilteredSender() = default;

SyncChannelFilteredSender::SyncChannelFilteredSender(
    IPC::ChannelHandle channel_handle,
    IPC::Listener* listener,
    scoped_refptr<base::SingleThreadTaskRunner> ipc_task_runner,
    base::WaitableEvent* shutdown_event)
    : channel_(IPC::SyncChannel::Create(channel_handle,
                                        IPC::Channel::MODE_SERVER,
                                        listener,
                                        ipc_task_runner,
                                        base::ThreadTaskRunnerHandle::Get(),
                                        false,
                                        shutdown_event)) {}

SyncChannelFilteredSender::~SyncChannelFilteredSender() = default;

bool SyncChannelFilteredSender::Send(IPC::Message* msg) {
  return channel_->Send(msg);
}

void SyncChannelFilteredSender::AddFilter(IPC::MessageFilter* filter) {
  channel_->AddFilter(filter);
}

void SyncChannelFilteredSender::RemoveFilter(IPC::MessageFilter* filter) {
  channel_->RemoveFilter(filter);
}

GpuChannel::GpuChannel(
    GpuChannelManager* gpu_channel_manager,
    Scheduler* scheduler,
    SyncPointManager* sync_point_manager,
    scoped_refptr<gl::GLShareGroup> share_group,
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
    int32_t client_id,
    uint64_t client_tracing_id,
    bool is_gpu_host)
    : gpu_channel_manager_(gpu_channel_manager),
      scheduler_(scheduler),
      sync_point_manager_(sync_point_manager),
      client_id_(client_id),
      client_tracing_id_(client_tracing_id),
      task_runner_(task_runner),
      io_task_runner_(io_task_runner),
      share_group_(share_group),
      image_manager_(new gles2::ImageManager()),
      is_gpu_host_(is_gpu_host),
      weak_factory_(this) {
  DCHECK(gpu_channel_manager_);
  DCHECK(client_id_);
  filter_ = new GpuChannelMessageFilter(this, scheduler, task_runner);
}

GpuChannel::~GpuChannel() {
  // Clear stubs first because of dependencies.
  stubs_.clear();

  // Destroy filter first so that scheduler gets no more messages.
  filter_->Destroy();

  for (const auto& kv : stream_sequences_)
    scheduler_->DestroySequence(kv.second);
}

void GpuChannel::Init(std::unique_ptr<FilteredSender> channel) {
  channel_ = std::move(channel);
  channel_->AddFilter(filter_.get());
}

void GpuChannel::SetUnhandledMessageListener(IPC::Listener* listener) {
  unhandled_message_listener_ = listener;
}

base::WeakPtr<GpuChannel> GpuChannel::AsWeakPtr() {
  return weak_factory_.GetWeakPtr();
}

base::ProcessId GpuChannel::GetClientPID() const {
  DCHECK_NE(peer_pid_, base::kNullProcessId);
  return peer_pid_;
}

bool GpuChannel::OnMessageReceived(const IPC::Message& msg) {
  // All messages should be pushed to channel_messages_ and handled separately.
  NOTREACHED();
  return false;
}

void GpuChannel::OnChannelConnected(int32_t peer_pid) {
  peer_pid_ = peer_pid;
}

void GpuChannel::OnChannelError() {
  gpu_channel_manager_->RemoveChannel(client_id_);
}

bool GpuChannel::Send(IPC::Message* message) {
  // The GPU process must never send a synchronous IPC message to the renderer
  // process. This could result in deadlock.
  DCHECK(!message->is_sync());

  DVLOG(1) << "sending message @" << message << " on channel @" << this
           << " with type " << message->type();

  if (!channel_) {
    delete message;
    return false;
  }

  return channel_->Send(message);
}

void GpuChannel::OnCommandBufferScheduled(CommandBufferStub* stub) {
  scheduler_->EnableSequence(stub->sequence_id());
}

void GpuChannel::OnCommandBufferDescheduled(CommandBufferStub* stub) {
  scheduler_->DisableSequence(stub->sequence_id());
}

CommandBufferStub* GpuChannel::LookupCommandBuffer(int32_t route_id) {
  auto it = stubs_.find(route_id);
  if (it == stubs_.end())
    return nullptr;

  return it->second.get();
}

bool GpuChannel::HasActiveWebGLContext() const {
  for (auto& kv : stubs_) {
    ContextType context_type =
        kv.second->context_group()->feature_info()->context_type();
    if (context_type == CONTEXT_TYPE_WEBGL1 ||
        context_type == CONTEXT_TYPE_WEBGL2) {
      return true;
    }
  }
  return false;
}

void GpuChannel::LoseAllContexts() {
  gpu_channel_manager_->LoseAllContexts();
}

void GpuChannel::MarkAllContextsLost() {
  for (auto& kv : stubs_)
    kv.second->MarkContextLost();
}

bool GpuChannel::AddRoute(int32_t route_id,
                          SequenceId sequence_id,
                          IPC::Listener* listener) {
  if (scheduler_)
    filter_->AddRoute(route_id, sequence_id);
  return router_.AddRoute(route_id, listener);
}

void GpuChannel::RemoveRoute(int32_t route_id) {
  if (scheduler_)
    filter_->RemoveRoute(route_id);
  router_.RemoveRoute(route_id);
}

bool GpuChannel::OnControlMessageReceived(const IPC::Message& msg) {
  bool handled = true;
  IPC_BEGIN_MESSAGE_MAP(GpuChannel, msg)
    IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateCommandBuffer,
                        OnCreateCommandBuffer)
    IPC_MESSAGE_HANDLER(GpuChannelMsg_DestroyCommandBuffer,
                        OnDestroyCommandBuffer)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP()
  return handled;
}

void GpuChannel::HandleMessage(const IPC::Message& msg) {
  int32_t routing_id = msg.routing_id();
  CommandBufferStub* stub = LookupCommandBuffer(routing_id);

  DCHECK(!stub || stub->IsScheduled());

  DVLOG(1) << "received message @" << &msg << " on channel @" << this
           << " with type " << msg.type();

  HandleMessageHelper(msg);

  // If we get descheduled or yield while processing a message.
  if (stub && (stub->HasUnprocessedCommands() || !stub->IsScheduled())) {
    DCHECK((uint32_t)GpuCommandBufferMsg_AsyncFlush::ID == msg.type() ||
           (uint32_t)GpuCommandBufferMsg_WaitSyncToken::ID == msg.type());
    scheduler_->ContinueTask(
        stub->sequence_id(),
        base::BindOnce(&GpuChannel::HandleMessage, AsWeakPtr(), msg));
  }
}

void GpuChannel::HandleMessageForTesting(const IPC::Message& msg) {
  // Message filter gets message first on IO thread.
  filter_->OnMessageReceived(msg);
}

void GpuChannel::HandleMessageHelper(const IPC::Message& msg) {
  int32_t routing_id = msg.routing_id();

  bool handled = false;
  if (routing_id == MSG_ROUTING_CONTROL) {
    handled = OnControlMessageReceived(msg);
  } else {
    handled = router_.RouteMessage(msg);
  }

  if (!handled && unhandled_message_listener_)
    handled = unhandled_message_listener_->OnMessageReceived(msg);

  // Respond to sync messages even if router failed to route.
  if (!handled && msg.is_sync()) {
    IPC::Message* reply = IPC::SyncMessage::GenerateReply(&msg);
    reply->set_reply_error();
    Send(reply);
  }
}

void GpuChannel::HandleOutOfOrderMessage(const IPC::Message& msg) {
  HandleMessageHelper(msg);
}

#if defined(OS_ANDROID)
const CommandBufferStub* GpuChannel::GetOneStub() const {
  for (const auto& kv : stubs_) {
    const CommandBufferStub* stub = kv.second.get();
    if (stub->decoder_context() && !stub->decoder_context()->WasContextLost())
      return stub;
  }
  return nullptr;
}
#endif

void GpuChannel::OnCreateCommandBuffer(
    const GPUCreateCommandBufferConfig& init_params,
    int32_t route_id,
    base::SharedMemoryHandle shared_state_handle,
    ContextResult* result,
    gpu::Capabilities* capabilities) {
  TRACE_EVENT2("gpu", "GpuChannel::OnCreateCommandBuffer", "route_id", route_id,
               "offscreen", (init_params.surface_handle == kNullSurfaceHandle));
  std::unique_ptr<base::SharedMemory> shared_state_shm(
      new base::SharedMemory(shared_state_handle, false));

  // Default result on failure. Override with a more accurate failure if needed,
  // or with success.
  *result = ContextResult::kFatalFailure;
  *capabilities = gpu::Capabilities();

  if (init_params.surface_handle != kNullSurfaceHandle && !is_gpu_host_) {
    LOG(ERROR)
        << "ContextResult::kFatalFailure: "
           "attempt to create a view context on a non-privileged channel";
    return;
  }

  int32_t stream_id = init_params.stream_id;
  int32_t share_group_id = init_params.share_group_id;
  CommandBufferStub* share_group = LookupCommandBuffer(share_group_id);

  if (!share_group && share_group_id != MSG_ROUTING_NONE) {
    LOG(ERROR) << "ContextResult::kFatalFailure: invalid share group id";
    return;
  }

  if (share_group && stream_id != share_group->stream_id()) {
    LOG(ERROR) << "ContextResult::kFatalFailure: "
                  "stream id does not match share group stream id";
    return;
  }

  if (share_group && !share_group->decoder_context()) {
    // This should catch test errors where we did not Initialize the
    // share_group's CommandBuffer.
    LOG(ERROR) << "ContextResult::kFatalFailure: "
                  "shared context was not initialized";
    return;
  }

  if (share_group && share_group->decoder_context()->WasContextLost()) {
    // The caller should retry to get a context.
    LOG(ERROR) << "ContextResult::kTransientFailure: "
                  "shared context was already lost";
    *result = gpu::ContextResult::kTransientFailure;
    return;
  }

  CommandBufferId command_buffer_id =
      GenerateCommandBufferId(client_id_, route_id);

  SequenceId sequence_id = stream_sequences_[stream_id];
  if (sequence_id.is_null()) {
    sequence_id = scheduler_->CreateSequence(init_params.stream_priority);
    stream_sequences_[stream_id] = sequence_id;
  }

  std::unique_ptr<CommandBufferStub> stub;
  // Check gpu_preferences() as well as attribs.enable_raster_decoder to prevent
  // compromised renderer from unilaterally enabling RasterDecoder.
  if (gpu_channel_manager_->gpu_preferences().enable_raster_decoder &&
      init_params.attribs.enable_raster_decoder &&
      init_params.attribs.enable_raster_interface &&
      !init_params.attribs.enable_gles2_interface) {
    stub = std::make_unique<RasterCommandBufferStub>(
        this, init_params, command_buffer_id, sequence_id, stream_id, route_id);
  } else {
    stub = std::make_unique<GLES2CommandBufferStub>(
        this, init_params, command_buffer_id, sequence_id, stream_id, route_id);
  }

  auto stub_result =
      stub->Initialize(share_group, init_params, std::move(shared_state_shm));
  if (stub_result != gpu::ContextResult::kSuccess) {
    DLOG(ERROR) << "GpuChannel::CreateCommandBuffer(): failed to initialize "
                   "CommandBufferStub";
    *result = stub_result;
    return;
  }

  if (!AddRoute(route_id, sequence_id, stub.get())) {
    LOG(ERROR) << "ContextResult::kFatalFailure: failed to add route";
    return;
  }

  *result = ContextResult::kSuccess;
  *capabilities = stub->decoder_context()->GetCapabilities();
  stubs_[route_id] = std::move(stub);
}

void GpuChannel::OnDestroyCommandBuffer(int32_t route_id) {
  TRACE_EVENT1("gpu", "GpuChannel::OnDestroyCommandBuffer", "route_id",
               route_id);

  std::unique_ptr<CommandBufferStub> stub;
  auto it = stubs_.find(route_id);
  if (it != stubs_.end()) {
    stub = std::move(it->second);
    stubs_.erase(it);
  }
  // In case the renderer is currently blocked waiting for a sync reply from the
  // stub, we need to make sure to reschedule the correct stream here.
  if (stub && !stub->IsScheduled()) {
    // This stub won't get a chance to be scheduled so do that now.
    OnCommandBufferScheduled(stub.get());
  }

  RemoveRoute(route_id);
}

void GpuChannel::CacheShader(const std::string& key,
                             const std::string& shader) {
  gpu_channel_manager_->delegate()->StoreShaderToDisk(client_id_, key, shader);
}

void GpuChannel::AddFilter(IPC::MessageFilter* filter) {
  io_task_runner_->PostTask(
      FROM_HERE, base::Bind(&GpuChannelMessageFilter::AddChannelFilter, filter_,
                            base::RetainedRef(filter)));
}

void GpuChannel::RemoveFilter(IPC::MessageFilter* filter) {
  io_task_runner_->PostTask(
      FROM_HERE, base::Bind(&GpuChannelMessageFilter::RemoveChannelFilter,
                            filter_, base::RetainedRef(filter)));
}

uint64_t GpuChannel::GetMemoryUsage() {
  // Collect the unique memory trackers in use by the |stubs_|.
  std::set<gles2::MemoryTracker*> unique_memory_trackers;
  for (auto& kv : stubs_)
    unique_memory_trackers.insert(kv.second->GetMemoryTracker());

  // Sum the memory usage for all unique memory trackers.
  uint64_t size = 0;
  for (auto* tracker : unique_memory_trackers) {
    size += gpu_channel_manager()->gpu_memory_manager()->GetTrackerMemoryUsage(
        tracker);
  }

  return size;
}

scoped_refptr<gl::GLImage> GpuChannel::CreateImageForGpuMemoryBuffer(
    const gfx::GpuMemoryBufferHandle& handle,
    const gfx::Size& size,
    gfx::BufferFormat format,
    uint32_t internalformat,
    SurfaceHandle surface_handle) {
  switch (handle.type) {
    case gfx::SHARED_MEMORY_BUFFER: {
      if (!base::IsValueInRangeForNumericType<size_t>(handle.stride))
        return nullptr;
      scoped_refptr<gl::GLImageSharedMemory> image(
          new gl::GLImageSharedMemory(size, internalformat));
      if (!image->Initialize(handle.handle, handle.id, format, handle.offset,
                             handle.stride)) {
        return nullptr;
      }

      return image;
    }
    default: {
      GpuChannelManager* manager = gpu_channel_manager();
      if (!manager->gpu_memory_buffer_factory())
        return nullptr;

      return manager->gpu_memory_buffer_factory()
          ->AsImageFactory()
          ->CreateImageForGpuMemoryBuffer(handle, size, format, internalformat,
                                          client_id_, surface_handle);
    }
  }
}

}  // namespace gpu