Implement TextureImageTransportSurface using texture mailbox

content/common/gpu/texture_image_transport_surface.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 "content/common/gpu/texture_image_transport_surface.h"
 
 #include <string>
 #include <vector>
 
 #include "base/command_line.h"
 #include "content/common/gpu/gl_scoped_binders.h"
 #include "content/common/gpu/gpu_channel.h"
 #include "content/common/gpu/gpu_channel_manager.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/gpu/sync_point_manager.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/service/context_group.h"
 #include "gpu/command_buffer/service/gpu_scheduler.h"
-#include "gpu/command_buffer/service/texture_manager.h"
+#include "gpu/command_buffer/service/texture_definition.h"
 
 using gpu::gles2::ContextGroup;
+using gpu::gles2::MailboxManager;
+using gpu::gles2::MailboxName;
+using gpu::gles2::TextureDefinition;
 using gpu::gles2::TextureManager;
-typedef TextureManager::TextureInfo TextureInfo;
 
 namespace content {
 
 TextureImageTransportSurface::Texture::Texture()
-    : client_id(0),
-      sent_to_client(false) {
+    : service_id(0),
+      identifier(0) {
 }
 
 TextureImageTransportSurface::Texture::~Texture() {
 }
 
 TextureImageTransportSurface::TextureImageTransportSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub,
     const gfx::GLSurfaceHandle& handle)
       : fbo_id_(0),
-        front_(0),
         stub_destroyed_(false),
         backbuffer_suggested_allocation_(true),
         frontbuffer_suggested_allocation_(true),
-        frontbuffer_is_protected_(true),
-        protection_state_id_(0),
         handle_(handle),
-        parent_stub_(NULL),
         is_swap_buffers_pending_(false),
-        did_unschedule_(false),
-        did_flip_(false) {
+        did_unschedule_(false) {
   helper_.reset(new ImageTransportHelper(this,
                                          manager,
                                          stub,
                                          gfx::kNullPluginWindow));
 }
 
 TextureImageTransportSurface::~TextureImageTransportSurface() {
   DCHECK(stub_destroyed_);
   Destroy();
 }
 
 bool TextureImageTransportSurface::Initialize() {
+  mailbox_manager_ =
+      helper_->stub()->decoder()->GetContextGroup()->mailbox_manager();
+
+  backbuffer_.identifier = 1;
+
   GpuChannelManager* manager = helper_->manager();
-  GpuChannel* parent_channel = manager->LookupChannel(handle_.parent_client_id);
-  if (!parent_channel)
-    return false;
-
-  parent_stub_ = parent_channel->LookupCommandBuffer(handle_.parent_context_id);
-  if (!parent_stub_)
-    return false;
-
-  parent_stub_->AddDestructionObserver(this);
-  TextureManager* texture_manager =
-      parent_stub_->decoder()->GetContextGroup()->texture_manager();
-  DCHECK(texture_manager);
-
-  for (int i = 0; i < 2; ++i) {
-    Texture& texture = textures_[i];
-    texture.client_id = handle_.parent_texture_id[i];
-    texture.info = texture_manager->GetTextureInfo(texture.client_id);
-    if (!texture.info)
-      return false;
-
-    if (!texture.info->target())
-      texture_manager->SetInfoTarget(texture.info, GL_TEXTURE_2D);
-    texture_manager->SetParameter(
-        texture.info, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-    texture_manager->SetParameter(
-        texture.info, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    texture_manager->SetParameter(
-        texture.info, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
-    texture_manager->SetParameter(
-        texture.info, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-  }
-
   surface_ = manager->GetDefaultOffscreenSurface();
   if (!surface_.get())
     return false;
 
   if (!helper_->Initialize())
     return false;
 
-  const CommandLine* command_line = CommandLine::ForCurrentProcess();
-  if (command_line->HasSwitch(switches::kUIPrioritizeInGpuProcess))
-    helper_->SetPreemptByCounter(parent_channel->MessagesPendingCount());
+  GpuChannel* parent_channel = manager->LookupChannel(handle_.parent_client_id);
+  if (parent_channel) {
+    const CommandLine* command_line = CommandLine::ForCurrentProcess();
+    if (command_line->HasSwitch(switches::kUIPrioritizeInGpuProcess))
+      helper_->SetPreemptByCounter(parent_channel->MessagesPendingCount());
+  }
 
   return true;
 }
 
 void TextureImageTransportSurface::Destroy() {
-  if (parent_stub_) {
-    parent_stub_->decoder()->MakeCurrent();
-    ReleaseParentStub();
+  if (!stub_destroyed_) {
+    GpuHostMsg_AcceleratedSurfaceRelease_Params params;
+    helper_->SendAcceleratedSurfaceRelease(params);
   }
 

[jonathan.backer, 2012/12/04 19:15:13]

Do we need a |ReleaseBackTexture()| here or in OnWillDestroyStub()? AFAICT, we
may leak otherwise. I think that we may have been able to get away with this
before because the browser would destroy the textures (maybe?).

[no sievers, 2012/12/05 22:02:34]

Good catch. I moved it (and the SendAcceleratedSurfaceRelease()) into
OnWillDestroyStub(), because here we won't have a context/stub anymore.

   if (surface_.get())
     surface_ = NULL;
 
   helper_->Destroy();
 }
 
 bool TextureImageTransportSurface::DeferDraws() {
   // The command buffer hit a draw/clear command that could clobber the
   // texture in use by the UI compositor. If a Swap is pending, abort
   // processing of the command by returning true and unschedule until the Swap
@@ skipping 16 matching lines @@
 }
 
 bool TextureImageTransportSurface::OnMakeCurrent(gfx::GLContext* context) {
   if (stub_destroyed_) {
     // Early-exit so that we don't recreate the fbo. We still want to return
     // true, so that the context is made current and the GLES2DecoderImpl can
     // release its own resources.
     return true;
   }
 
+  if (!context_.get()) {
+    DCHECK(helper_->stub());
+    context_ = helper_->stub()->decoder()->GetGLContext();
+  }
+
   if (!fbo_id_) {
     glGenFramebuffersEXT(1, &fbo_id_);
     glBindFramebufferEXT(GL_FRAMEBUFFER, fbo_id_);
-    CreateBackTexture(gfx::Size(1, 1));
+    current_size_ = gfx::Size(1, 1);
+    helper_->stub()->AddDestructionObserver(this);
+  }
+
+  // We could be receiving non-deferred GL commands, that is anything that does
+  // not need a framebuffer.
+  if (!backbuffer_.service_id && !is_swap_buffers_pending_ &&
+      backbuffer_suggested_allocation_) {
+    CreateBackTexture();
 
 #ifndef NDEBUG
     GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER);
     if (status != GL_FRAMEBUFFER_COMPLETE) {
       DLOG(ERROR) << "Framebuffer incomplete.";
       glDeleteFramebuffersEXT(1, &fbo_id_);
       fbo_id_ = 0;
       return false;
     }
 #endif
-    DCHECK(helper_->stub());
-    helper_->stub()->AddDestructionObserver(this);
   }
-
   return true;
 }
 
 unsigned int TextureImageTransportSurface::GetBackingFrameBufferObject() {
   return fbo_id_;
 }
 
 void TextureImageTransportSurface::SetBackbufferAllocation(bool allocation) {
   DCHECK(!is_swap_buffers_pending_);
   if (backbuffer_suggested_allocation_ == allocation)
      return;
   backbuffer_suggested_allocation_ = allocation;
 
-  if (!helper_->MakeCurrent())
-    return;
-
   if (backbuffer_suggested_allocation_) {
-    DCHECK(!textures_[back()].info->service_id() ||
-           !textures_[back()].sent_to_client);
-    CreateBackTexture(textures_[back()].size);
+    DCHECK(!backbuffer_.service_id);
+    CreateBackTexture();
   } else {
-    ReleaseTexture(back());
+    ReleaseBackTexture();
   }
 }
 
 void TextureImageTransportSurface::SetFrontbufferAllocation(bool allocation) {
   if (frontbuffer_suggested_allocation_ == allocation)
     return;
   frontbuffer_suggested_allocation_ = allocation;
   AdjustFrontBufferAllocation();
 }
 
 void TextureImageTransportSurface::AdjustFrontBufferAllocation() {

[jonathan.backer, 2012/12/04 19:15:13]

Can we nuke this separate method? AFAICT, it's only called in one place now (it
used to be called in OnSetFrontSurfaceIsProtected as well).

[no sievers, 2012/12/05 22:02:34]

Done.

-  if (!helper_->MakeCurrent())
-    return;
-
-  if (!frontbuffer_suggested_allocation_ && !frontbuffer_is_protected_ &&
-      textures_[front()].info->service_id()) {
-    ReleaseTexture(front());
-    if (textures_[front()].sent_to_client) {
-      GpuHostMsg_AcceleratedSurfaceRelease_Params params;
-      params.identifier = textures_[front()].client_id;
-      helper_->SendAcceleratedSurfaceRelease(params);
-      textures_[front()].sent_to_client = false;
-    }
+  if (!frontbuffer_suggested_allocation_) {
+    GpuHostMsg_AcceleratedSurfaceRelease_Params params;
+    helper_->SendAcceleratedSurfaceRelease(params);
   }
 }
 
 void* TextureImageTransportSurface::GetShareHandle() {
   return GetHandle();
 }
 
 void* TextureImageTransportSurface::GetDisplay() {
   return surface_.get() ? surface_->GetDisplay() : NULL;
 }
 
 void* TextureImageTransportSurface::GetConfig() {
   return surface_.get() ? surface_->GetConfig() : NULL;
 }
 
 void TextureImageTransportSurface::OnResize(gfx::Size size) {
-  CreateBackTexture(size);
+  current_size_ = size;
+  CreateBackTexture();
 }
 
 void TextureImageTransportSurface::OnWillDestroyStub(
     GpuCommandBufferStub* stub) {
-  if (stub == parent_stub_) {
-    ReleaseParentStub();
-    helper_->SetPreemptByCounter(NULL);
-  } else {
-    DCHECK(stub == helper_->stub());
-    stub->RemoveDestructionObserver(this);
+  DCHECK(stub == helper_->stub());
+  stub->RemoveDestructionObserver(this);
 
-    // We are losing the stub owning us, this is our last chance to clean up the
-    // resources we allocated in the stub's context.
-    if (fbo_id_) {
-      glDeleteFramebuffersEXT(1, &fbo_id_);
-      CHECK_GL_ERROR();
-      fbo_id_ = 0;
-    }
+  // We are losing the stub owning us, this is our last chance to clean up the
+  // resources we allocated in the stub's context.
+  if (fbo_id_) {
+    glDeleteFramebuffersEXT(1, &fbo_id_);
+    CHECK_GL_ERROR();
+    fbo_id_ = 0;
+  }
 
-    stub_destroyed_ = true;
-  }
+  stub_destroyed_ = true;
 }
 
 bool TextureImageTransportSurface::SwapBuffers() {
   DCHECK(backbuffer_suggested_allocation_);
-  if (!frontbuffer_suggested_allocation_ || !frontbuffer_is_protected_)
+  if (!frontbuffer_suggested_allocation_)
     return true;
-  if (!parent_stub_) {
-    LOG(ERROR) << "SwapBuffers failed because no parent stub.";
-    return false;
-  }
 
   glFlush();
-  front_ = back();
-  previous_damage_rect_ = gfx::Rect(textures_[front()].size);
+  const uint64 identifier = backbuffer_.identifier;

[jonathan.backer, 2012/12/04 19:15:13]

nit: nix identifier

[no sievers, 2012/12/05 22:02:34]

Done.

+  ProduceTexture(backbuffer_);
 
-  DCHECK(textures_[front()].client_id != 0);
+  // Do not allow destruction while we are still waiting for a swap ACK,
+  // so we do not leak a texture in the mailbox.
+  AddRef();
 
   GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
-  params.surface_handle = textures_[front()].client_id;
-  params.size = textures_[front()].size;
-  params.protection_state_id = protection_state_id_;
-  params.skip_ack = false;
+  params.surface_handle = identifier;
+  params.size = current_size_;

[jonathan.backer, 2012/12/04 19:15:13]

|backbuffer_.size| instead (they should be equal)

[no sievers, 2012/12/05 22:02:34]

Done.

   helper_->SendAcceleratedSurfaceBuffersSwapped(params);
 
   DCHECK(!is_swap_buffers_pending_);
   is_swap_buffers_pending_ = true;
   return true;
 }
 
 bool TextureImageTransportSurface::PostSubBuffer(
     int x, int y, int width, int height) {
   DCHECK(backbuffer_suggested_allocation_);
-  DCHECK(textures_[back()].info->service_id());
-  if (!frontbuffer_suggested_allocation_ || !frontbuffer_is_protected_)
+  if (!frontbuffer_suggested_allocation_)
     return true;
-  // If we are recreating the frontbuffer with this swap, make sure we are
-  // drawing a full frame.
-  DCHECK(textures_[front()].info->service_id() ||
-         (!x && !y && gfx::Size(width, height) == textures_[back()].size));
-  if (!parent_stub_) {
-    LOG(ERROR) << "PostSubBuffer failed because no parent stub.";
-    return false;
-  }
-
   const gfx::Rect new_damage_rect(x, y, width, height);
+  DCHECK(gfx::Rect(gfx::Point(), current_size_).Contains(new_damage_rect));
 
   // An empty damage rect is a successful no-op.
   if (new_damage_rect.IsEmpty())
     return true;
 
-  int back_texture_service_id = textures_[back()].info->service_id();
-  int front_texture_service_id = textures_[front()].info->service_id();
+  glFlush();
+  const uint64 identifier = backbuffer_.identifier;

[jonathan.backer, 2012/12/04 19:15:13]

nit: nix identifier

[no sievers, 2012/12/05 22:02:34]

Done.

+  ProduceTexture(backbuffer_);
 
-  gfx::Size expected_size = textures_[back()].size;
-  bool surfaces_same_size = textures_[front()].size == expected_size;
-
-  if (surfaces_same_size) {
-    std::vector<gfx::Rect> regions_to_copy;
-    GetRegionsToCopy(previous_damage_rect_, new_damage_rect, &regions_to_copy);
-
-    ScopedFrameBufferBinder fbo_binder(fbo_id_);
-    glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
-        GL_COLOR_ATTACHMENT0,
-        GL_TEXTURE_2D,
-        front_texture_service_id,
-        0);
-    ScopedTextureBinder texture_binder(back_texture_service_id);
-
-    for (size_t i = 0; i < regions_to_copy.size(); ++i) {
-      const gfx::Rect& region_to_copy = regions_to_copy[i];
-      if (!region_to_copy.IsEmpty()) {
-        glCopyTexSubImage2D(GL_TEXTURE_2D, 0, region_to_copy.x(),
-            region_to_copy.y(), region_to_copy.x(), region_to_copy.y(),
-            region_to_copy.width(), region_to_copy.height());
-      }
-    }
-  } else if (!surfaces_same_size && did_flip_) {
-    DCHECK(new_damage_rect == gfx::Rect(expected_size));
-  }
-
-  glFlush();
-  front_ = back();
-  previous_damage_rect_ = new_damage_rect;
-
-  DCHECK(textures_[front()].client_id);
+  // Do not allow destruction while we are still waiting for a swap ACK,
+  // so we do not leak a texture in the mailbox.
+  AddRef();
 
   GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params params;
-  params.surface_handle = textures_[front()].client_id;
-  params.surface_size = textures_[front()].size;
+  params.surface_handle = identifier;
+  params.surface_size = current_size_;

[jonathan.backer, 2012/12/04 19:15:13]

|backbuffer_.size| instead?

[no sievers, 2012/12/05 22:02:34]

Done.

   params.x = x;
   params.y = y;
   params.width = width;
   params.height = height;
-  params.protection_state_id = protection_state_id_;
   helper_->SendAcceleratedSurfacePostSubBuffer(params);
 
   DCHECK(!is_swap_buffers_pending_);
   is_swap_buffers_pending_ = true;
   return true;
 }
 
 std::string TextureImageTransportSurface::GetExtensions() {
   std::string extensions = gfx::GLSurface::GetExtensions();
   extensions += extensions.empty() ? "" : " ";
   extensions += "GL_CHROMIUM_front_buffer_cached ";
   extensions += "GL_CHROMIUM_post_sub_buffer";
   return extensions;
 }
 
 gfx::Size TextureImageTransportSurface::GetSize() {
-  gfx::Size size = textures_[back()].size;
+  gfx::Size size = current_size_;
 
   // OSMesa expects a non-zero size.
   return gfx::Size(size.width() == 0 ? 1 : size.width(),
                    size.height() == 0 ? 1 : size.height());
 }
 
 void* TextureImageTransportSurface::GetHandle() {
   return surface_.get() ? surface_->GetHandle() : NULL;
 }
 
 unsigned TextureImageTransportSurface::GetFormat() {
   return surface_.get() ? surface_->GetFormat() : 0;
 }
 
-void TextureImageTransportSurface::OnSetFrontSurfaceIsProtected(
-    bool is_protected, uint32 protection_state_id) {
-  protection_state_id_ = protection_state_id;
-  if (frontbuffer_is_protected_ == is_protected)
-    return;
-  frontbuffer_is_protected_ = is_protected;
-  AdjustFrontBufferAllocation();
-
-  // If surface is set to protected, and we haven't actually released it yet,
-  // we can set the ui surface handle now just by sending a swap message.
-  if (is_protected && textures_[front()].info->service_id() &&
-      textures_[front()].sent_to_client) {
-    GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
-    params.surface_handle = textures_[front()].client_id;
-    params.size = textures_[front()].size;
-    params.protection_state_id = protection_state_id_;
-    params.skip_ack = true;
-    helper_->SendAcceleratedSurfaceBuffersSwapped(params);
-  }
-}
-
-void TextureImageTransportSurface::OnBufferPresented(bool presented,
+void TextureImageTransportSurface::OnBufferPresented(uint64 surface_handle,
                                                      uint32 sync_point) {
   if (sync_point == 0) {
-    BufferPresentedImpl(presented);
+    BufferPresentedImpl(surface_handle);
   } else {
     helper_->manager()->sync_point_manager()->AddSyncPointCallback(
         sync_point,
         base::Bind(&TextureImageTransportSurface::BufferPresentedImpl,
-                   this->AsWeakPtr(),
-                   presented));
+                   this,
+                   surface_handle));
   }
+
+  // Careful, we might get deleted now if we were only waiting for
+  // a final swap ACK.
+  Release();
 }
 
-void TextureImageTransportSurface::BufferPresentedImpl(bool presented) {
+void TextureImageTransportSurface::BufferPresentedImpl(uint64 surface_handle) {
+  DCHECK(!backbuffer_.service_id);
+  if (surface_handle) {
+    DCHECK(surface_handle == 1 || surface_handle == 2);
+    backbuffer_.identifier = surface_handle;
+    ConsumeTexture(backbuffer_);
+  } else {
+    // We didn't get back a texture, so allocate 'the other' buffer.
+    backbuffer_.identifier = (backbuffer_.identifier == 1) ? 2 : 1;
+    mailbox_name(backbuffer_.identifier) = MailboxName();
+  }
+
+  if (stub_destroyed_ && backbuffer_.service_id) {
+    // TODO(sievers): Remove this after changes to the mailbox to take ownership
+    // of the service ids.
+    DCHECK(context_.get() && surface_.get());
+    if (context_->MakeCurrent(surface_.get()))
+      glDeleteTextures(1, &backbuffer_.service_id);
+
+    return;
+  }
+
   DCHECK(is_swap_buffers_pending_);
   is_swap_buffers_pending_ = false;
 
-  if (presented) {
-    // If we had not flipped, the two frame damage tracking is inconsistent.
-    // So conservatively take the whole frame.
-    if (!did_flip_)
-      previous_damage_rect_ = gfx::Rect(textures_[front()].size);
-  } else {
-    front_ = back();
-    previous_damage_rect_ = gfx::Rect(0, 0, 0, 0);
-  }
-
-  did_flip_ = presented;
+  // We should not have allowed the backbuffer to be discarded while the ack
+  // was pending.
+  DCHECK(backbuffer_suggested_allocation_);
 
   // We're relying on the fact that the parent context is
   // finished with it's context when it inserts the sync point that
   // triggers this callback.
   if (helper_->MakeCurrent()) {
-    if (textures_[front()].size != textures_[back()].size ||
-        !textures_[back()].info->service_id() ||
-        !textures_[back()].sent_to_client) {
-      // We may get an ACK from a stale swap just to reschedule.  In that case,
-      // we may not have a backbuffer suggestion and should not recreate one.
-      if (backbuffer_suggested_allocation_)
-        CreateBackTexture(textures_[front()].size);
-    } else {
+    if (backbuffer_.size != current_size_ || !backbuffer_.service_id)

[jonathan.backer, 2012/12/04 19:15:13]

AFAICT, it's only in this method and OnResize that |backbuffer_.size| could not
be equal |current_size_|. I propose nixing |current_size_| and using
|backbuffer_.size| wherever possible. IIRC, this is how it used to work. It's
less state that could get out of sync. I don't feel strongly about this.

[no sievers, 2012/12/05 22:02:34]

But we used to have the frontbuffer size also which we would compare against the
backbuffer size.
I need the separate variable in case the buffer we last sent had been resized.
Then the buffer we get back here (which is the other buffer) still has the old
size.

+      CreateBackTexture();
+    else
       AttachBackTextureToFBO();
-    }
   }
 
   // Even if MakeCurrent fails, schedule anyway, to trigger the lost context
   // logic.
   if (did_unschedule_) {
     did_unschedule_ = false;
     helper_->SetScheduled(true);
   }
 }
 
 void TextureImageTransportSurface::OnResizeViewACK() {
   NOTREACHED();
 }
 
-void TextureImageTransportSurface::ReleaseTexture(int id) {
-  if (!parent_stub_)
+void TextureImageTransportSurface::ReleaseBackTexture() {

[jonathan.backer, 2012/12/04 19:15:13]

Modulo the comment I made about leaking before, currently this is called from
only one place. I'd move the code there.

+  if (!backbuffer_.service_id)
     return;
-  Texture& texture = textures_[id];
-  TextureInfo* info = texture.info;
-  DCHECK(info);
 
-  GLuint service_id = info->service_id();
-  if (!service_id)
-    return;
-  info->SetServiceId(0);
-
-  {
-    ScopedFrameBufferBinder fbo_binder(fbo_id_);
-    glDeleteTextures(1, &service_id);
-  }
+  glDeleteTextures(1, &backbuffer_.service_id);
+  backbuffer_.service_id = 0;
+  mailbox_name(backbuffer_.identifier) = MailboxName();
   glFlush();
   CHECK_GL_ERROR();
 }
 
-void TextureImageTransportSurface::CreateBackTexture(const gfx::Size& size) {
-  if (!parent_stub_)
-    return;
-  Texture& texture = textures_[back()];
-  TextureInfo* info = texture.info;
-  DCHECK(info);
+void TextureImageTransportSurface::CreateBackTexture() {
+  // If |is_swap_buffers_pending| we are waiting for our backbuffer
+  // in the mailbox, so we shouldn't be reallocating it now.
+  DCHECK(!is_swap_buffers_pending_);
 
-  GLuint service_id = info->service_id();
-
-  if (service_id && texture.size == size && texture.sent_to_client)
+  if (backbuffer_.service_id && backbuffer_.size == current_size_)
     return;
 
-  if (!service_id) {
-    glGenTextures(1, &service_id);
-    info->SetServiceId(service_id);
+  if (!backbuffer_.service_id) {
+    MailboxName new_mailbox_name;
+    MailboxName& name = mailbox_name(backbuffer_.identifier);
+    // This slot should be uninitialized.
+    DCHECK(!memcmp(&name, &new_mailbox_name, sizeof(MailboxName)));
+    mailbox_manager_->GenerateMailboxName(&new_mailbox_name);
+    name = new_mailbox_name;
+    glGenTextures(1, &backbuffer_.service_id);
   }
 
-  if (size != texture.size) {
-    texture.size = size;
-    TextureManager* texture_manager =
-        parent_stub_->decoder()->GetContextGroup()->texture_manager();
-    texture_manager->SetLevelInfo(
-        info,
-        GL_TEXTURE_2D,
-        0,
-        GL_RGBA,
-        size.width(),
-        size.height(),
-        1,
-        0,
-        GL_RGBA,
-        GL_UNSIGNED_BYTE,
-        true);
-  }
+  backbuffer_.size = current_size_;
 
   {
-    ScopedTextureBinder texture_binder(service_id);
+    ScopedTextureBinder texture_binder(backbuffer_.service_id);
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
-        size.width(), size.height(), 0,
+        current_size_.width(), current_size_.height(), 0,
         GL_RGBA, GL_UNSIGNED_BYTE, NULL);
     CHECK_GL_ERROR();
   }
 
   AttachBackTextureToFBO();
 
+  const MailboxName& name = mailbox_name(backbuffer_.identifier);
+
   GpuHostMsg_AcceleratedSurfaceNew_Params params;
-  params.width = size.width();
-  params.height = size.height();
-  params.surface_handle = texture.client_id;
+  params.width = current_size_.width();
+  params.height = current_size_.height();
+  params.surface_handle = backbuffer_.identifier;
+  params.mailbox_name.append(
+      reinterpret_cast<const char*>(&name), sizeof(name));
   helper_->SendAcceleratedSurfaceNew(params);
-  texture.sent_to_client = true;
 }
 
 void TextureImageTransportSurface::AttachBackTextureToFBO() {
-  if (!parent_stub_)
-    return;
-  TextureInfo* info = textures_[back()].info;
-  DCHECK(info);
-
+  DCHECK(backbuffer_.service_id);
   ScopedFrameBufferBinder fbo_binder(fbo_id_);
   glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
       GL_COLOR_ATTACHMENT0,
       GL_TEXTURE_2D,
-      info->service_id(),
+      backbuffer_.service_id,
       0);
   glFlush();
   CHECK_GL_ERROR();
 
 #ifndef NDEBUG
   GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER);
   if (status != GL_FRAMEBUFFER_COMPLETE) {
-    DLOG(ERROR) << "Framebuffer incomplete.";
+    DLOG(FATAL) << "Framebuffer incomplete: " << status;
   }
 #endif
 }
 
-void TextureImageTransportSurface::ReleaseParentStub() {
-  DCHECK(parent_stub_);
-  parent_stub_->RemoveDestructionObserver(this);
-  for (int i = 0; i < 2; ++i) {
-    Texture& texture = textures_[i];
-    texture.info = NULL;
-    if (!texture.sent_to_client)
-      continue;
-    GpuHostMsg_AcceleratedSurfaceRelease_Params params;
-    params.identifier = texture.client_id;
-    helper_->SendAcceleratedSurfaceRelease(params);
+void TextureImageTransportSurface::ConsumeTexture(Texture& texture) {
+  DCHECK(!texture.service_id);
+  DCHECK(texture.identifier == 1 || texture.identifier == 2);
+
+  scoped_ptr<TextureDefinition> definition(mailbox_manager_->ConsumeTexture(
+      GL_TEXTURE_2D, mailbox_name(texture.identifier)));
+  if (definition.get()) {
+    texture.service_id = definition->ReleaseServiceId();
+    texture.size = gfx::Size(definition->level_infos()[0][0].width,
+                             definition->level_infos()[0][0].height);
   }
-  parent_stub_ = NULL;
+}
+
+void TextureImageTransportSurface::ProduceTexture(Texture& texture) {
+  DCHECK(texture.service_id);
+  DCHECK(texture.identifier == 1 || texture.identifier == 2);
+  TextureManager* texture_manager =
+      helper_->stub()->decoder()->GetContextGroup()->texture_manager();
+  DCHECK(texture.size.width() > 0 && texture.size.height() > 0);
+  TextureDefinition::LevelInfo info(
+      GL_TEXTURE_2D, GL_RGBA, texture.size.width(), texture.size.height(), 1,
+      0, GL_RGBA, GL_UNSIGNED_BYTE, true);
+
+  TextureDefinition::LevelInfos level_infos;
+  level_infos.resize(1);
+  level_infos[0].resize(texture_manager->MaxLevelsForTarget(GL_TEXTURE_2D));
+  level_infos[0][0] = info;
+  scoped_ptr<TextureDefinition> definition(new TextureDefinition(
+      GL_TEXTURE_2D,
+      texture.service_id,
+      true,
+      level_infos));
+  // Pass NULL as |owner| here to avoid errors from glConsumeTextureCHROMIUM()
+  // when the renderer context group goes away before the RWHV handles a pending
+  // ACK. We avoid leaking a texture in the mailbox by waiting for the final ACK
+  // at which point we consume the correct texture back.
+  mailbox_manager_->ProduceTexture(
+      GL_TEXTURE_2D,
+      mailbox_name(texture.identifier),
+      definition.release(),
+      NULL);
+  texture.service_id = 0;
 }
 
 }  // namespace content