path: root/gfx/layers/composite/TextureHost.cpp

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "TextureHost.h"

#include "CompositableHost.h"           // for CompositableHost
#include "LayerScope.h"
#include "LayersLogging.h"              // for AppendToString
#include "mozilla/gfx/2D.h"             // for DataSourceSurface, Factory
#include "mozilla/ipc/Shmem.h"          // for Shmem
#include "mozilla/layers/CompositableTransactionParent.h" // for CompositableParentManager
#include "mozilla/layers/CompositorBridgeParent.h"
#include "mozilla/layers/Compositor.h"  // for Compositor
#include "mozilla/layers/ISurfaceAllocator.h"  // for ISurfaceAllocator
#include "mozilla/layers/LayersSurfaces.h"  // for SurfaceDescriptor, etc
#include "mozilla/layers/TextureHostBasic.h"
#include "mozilla/layers/TextureHostOGL.h"  // for TextureHostOGL
#include "mozilla/layers/ImageDataSerializer.h"
#include "mozilla/layers/TextureClient.h"
#include "mozilla/layers/GPUVideoTextureHost.h"
#include "nsAString.h"
#include "mozilla/RefPtr.h"                   // for nsRefPtr
#include "nsPrintfCString.h"            // for nsPrintfCString
#include "mozilla/layers/PTextureParent.h"
#include "mozilla/Unused.h"
#include <limits>
#include "../opengl/CompositorOGL.h"
#include "gfxPrefs.h"
#include "gfxUtils.h"
#include "IPDLActor.h"

#ifdef MOZ_ENABLE_D3D10_LAYER
#include "../d3d11/CompositorD3D11.h"
#endif

#ifdef MOZ_X11
#include "mozilla/layers/X11TextureHost.h"
#endif

#ifdef XP_MACOSX
#include "../opengl/MacIOSurfaceTextureHostOGL.h"
#endif

#ifdef XP_WIN
#include "mozilla/layers/TextureDIB.h"
#endif

#if 0
#define RECYCLE_LOG(...) printf_stderr(__VA_ARGS__)
#else
#define RECYCLE_LOG(...) do { } while (0)
#endif

namespace mozilla {
namespace layers {

/**
 * TextureParent is the host-side IPDL glue between TextureClient and TextureHost.
 * It is an IPDL actor just like LayerParent, CompositableParent, etc.
 */
class TextureParent : public ParentActor<PTextureParent>
{
public:
  explicit TextureParent(HostIPCAllocator* aAllocator, uint64_t aSerial);

  ~TextureParent();

  bool Init(const SurfaceDescriptor& aSharedData,
            const LayersBackend& aLayersBackend,
            const TextureFlags& aFlags);

  void NotifyNotUsed(uint64_t aTransactionId);

  virtual bool RecvRecycleTexture(const TextureFlags& aTextureFlags) override;

  TextureHost* GetTextureHost() { return mTextureHost; }

  virtual void Destroy() override;

  uint64_t GetSerial() const { return mSerial; }

  virtual bool RecvDestroySync() override {
    DestroyIfNeeded();
    return true;
  }

  HostIPCAllocator* mSurfaceAllocator;
  RefPtr<TextureHost> mTextureHost;
  // mSerial is unique in TextureClient's process.
  const uint64_t mSerial;
};

////////////////////////////////////////////////////////////////////////////////
PTextureParent*
TextureHost::CreateIPDLActor(HostIPCAllocator* aAllocator,
                             const SurfaceDescriptor& aSharedData,
                             LayersBackend aLayersBackend,
                             TextureFlags aFlags,
                             uint64_t aSerial)
{
  TextureParent* actor = new TextureParent(aAllocator, aSerial);
  if (!actor->Init(aSharedData, aLayersBackend, aFlags)) {
    actor->ActorDestroy(ipc::IProtocol::ActorDestroyReason::FailedConstructor);
    delete actor;
    return nullptr;
  }
  return actor;
}

// static
bool
TextureHost::DestroyIPDLActor(PTextureParent* actor)
{
  delete actor;
  return true;
}

// static
bool
TextureHost::SendDeleteIPDLActor(PTextureParent* actor)
{
  return PTextureParent::Send__delete__(actor);
}

// static
TextureHost*
TextureHost::AsTextureHost(PTextureParent* actor)
{
  if (!actor) {
    return nullptr;
  }
  return static_cast<TextureParent*>(actor)->mTextureHost;
}

// static
uint64_t
TextureHost::GetTextureSerial(PTextureParent* actor)
{
  if (!actor) {
    return UINT64_MAX;
  }
  return static_cast<TextureParent*>(actor)->mSerial;
}

PTextureParent*
TextureHost::GetIPDLActor()
{
  return mActor;
}

void
TextureHost::SetLastFwdTransactionId(uint64_t aTransactionId)
{
  MOZ_ASSERT(mFwdTransactionId <= aTransactionId);
  mFwdTransactionId = aTransactionId;
}

// implemented in TextureHostOGL.cpp
already_AddRefed<TextureHost> CreateTextureHostOGL(const SurfaceDescriptor& aDesc,
                                               ISurfaceAllocator* aDeallocator,
                                               TextureFlags aFlags);

// implemented in TextureHostBasic.cpp
already_AddRefed<TextureHost> CreateTextureHostBasic(const SurfaceDescriptor& aDesc,
                                                 ISurfaceAllocator* aDeallocator,
                                                 TextureFlags aFlags);

// implemented in TextureD3D11.cpp
already_AddRefed<TextureHost> CreateTextureHostD3D11(const SurfaceDescriptor& aDesc,
                                                 ISurfaceAllocator* aDeallocator,
                                                 TextureFlags aFlags);

// implemented in TextureD3D9.cpp
already_AddRefed<TextureHost> CreateTextureHostD3D9(const SurfaceDescriptor& aDesc,
                                                ISurfaceAllocator* aDeallocator,
                                                TextureFlags aFlags);

already_AddRefed<TextureHost>
TextureHost::Create(const SurfaceDescriptor& aDesc,
                    ISurfaceAllocator* aDeallocator,
                    LayersBackend aBackend,
                    TextureFlags aFlags)
{
  switch (aDesc.type()) {
    case SurfaceDescriptor::TSurfaceDescriptorBuffer:
    case SurfaceDescriptor::TSurfaceDescriptorDIB:
    case SurfaceDescriptor::TSurfaceDescriptorFileMapping:
    case SurfaceDescriptor::TSurfaceDescriptorGPUVideo:
      return CreateBackendIndependentTextureHost(aDesc, aDeallocator, aFlags);

    case SurfaceDescriptor::TEGLImageDescriptor:
    case SurfaceDescriptor::TSurfaceTextureDescriptor:
    case SurfaceDescriptor::TSurfaceDescriptorSharedGLTexture:
      return CreateTextureHostOGL(aDesc, aDeallocator, aFlags);

    case SurfaceDescriptor::TSurfaceDescriptorMacIOSurface:
      if (aBackend == LayersBackend::LAYERS_OPENGL) {
        return CreateTextureHostOGL(aDesc, aDeallocator, aFlags);
      } else {
        return CreateTextureHostBasic(aDesc, aDeallocator, aFlags);
      }

#ifdef MOZ_X11
    case SurfaceDescriptor::TSurfaceDescriptorX11: {
      if (!aDeallocator->IsSameProcess()) {
        NS_ERROR("A client process is trying to peek at our address space using a X11Texture!");
        return nullptr;
      }

      const SurfaceDescriptorX11& desc = aDesc.get_SurfaceDescriptorX11();
      return MakeAndAddRef<X11TextureHost>(aFlags, desc);
    }
#endif

#ifdef XP_WIN
    case SurfaceDescriptor::TSurfaceDescriptorD3D9:
      return CreateTextureHostD3D9(aDesc, aDeallocator, aFlags);

    case SurfaceDescriptor::TSurfaceDescriptorD3D10:
    case SurfaceDescriptor::TSurfaceDescriptorDXGIYCbCr:
      if (aBackend == LayersBackend::LAYERS_D3D9) {
        return CreateTextureHostD3D9(aDesc, aDeallocator, aFlags);
      } else {
        return CreateTextureHostD3D11(aDesc, aDeallocator, aFlags);
      }
#endif
    default:
      MOZ_CRASH("GFX: Unsupported Surface type host");
  }
}

already_AddRefed<TextureHost>
CreateBackendIndependentTextureHost(const SurfaceDescriptor& aDesc,
                                    ISurfaceAllocator* aDeallocator,
                                    TextureFlags aFlags)
{
  RefPtr<TextureHost> result;
  switch (aDesc.type()) {
    case SurfaceDescriptor::TSurfaceDescriptorBuffer: {
      const SurfaceDescriptorBuffer& bufferDesc = aDesc.get_SurfaceDescriptorBuffer();
      const MemoryOrShmem& data = bufferDesc.data();
      switch (data.type()) {
        case MemoryOrShmem::TShmem: {
          const ipc::Shmem& shmem = data.get_Shmem();
          const BufferDescriptor& desc = bufferDesc.desc();
          if (!shmem.IsReadable()) {
            // We failed to map the shmem so we can't verify its size. This
            // should not be a fatal error, so just create the texture with
            // nothing backing it.
            result = new ShmemTextureHost(shmem, desc, aDeallocator, aFlags);
            break;
          }

          size_t bufSize = shmem.Size<char>();
          size_t reqSize = SIZE_MAX;
          switch (desc.type()) {
            case BufferDescriptor::TYCbCrDescriptor: {
              const YCbCrDescriptor& ycbcr = desc.get_YCbCrDescriptor();
              reqSize =
                ImageDataSerializer::ComputeYCbCrBufferSize(ycbcr.ySize(), ycbcr.cbCrSize(),
                                                            ycbcr.yOffset(), ycbcr.cbOffset(),
                                                            ycbcr.crOffset());
              break;
            }
            case BufferDescriptor::TRGBDescriptor: {
              const RGBDescriptor& rgb = desc.get_RGBDescriptor();
              reqSize = ImageDataSerializer::ComputeRGBBufferSize(rgb.size(), rgb.format());
              break;
            }
            default:
              gfxCriticalError() << "Bad buffer host descriptor " << (int)desc.type();
              MOZ_CRASH("GFX: Bad descriptor");
          }

          if (reqSize == 0 || bufSize < reqSize) {
            NS_ERROR("A client process gave a shmem too small to fit for its descriptor!");
            return nullptr;
          }

          result = new ShmemTextureHost(shmem, desc, aDeallocator, aFlags);
          break;
        }
        case MemoryOrShmem::Tuintptr_t: {
          if (!aDeallocator->IsSameProcess()) {
            NS_ERROR("A client process is trying to peek at our address space using a MemoryTexture!");
            return nullptr;
          }

          result = new MemoryTextureHost(reinterpret_cast<uint8_t*>(data.get_uintptr_t()),
                                         bufferDesc.desc(),
                                         aFlags);
          break;
        }
        default:
          gfxCriticalError() << "Failed texture host for backend " << (int)data.type();
          MOZ_CRASH("GFX: No texture host for backend");
      }
      break;
    }
    case SurfaceDescriptor::TSurfaceDescriptorGPUVideo: {
      result = new GPUVideoTextureHost(aFlags, aDesc.get_SurfaceDescriptorGPUVideo());
      break;
    }
#ifdef XP_WIN
    case SurfaceDescriptor::TSurfaceDescriptorDIB: {
      if (!aDeallocator->IsSameProcess()) {
        NS_ERROR("A client process is trying to peek at our address space using a DIBTexture!");
        return nullptr;
      }

      result = new DIBTextureHost(aFlags, aDesc);
      break;
    }
    case SurfaceDescriptor::TSurfaceDescriptorFileMapping: {
      result = new TextureHostFileMapping(aFlags, aDesc);
      break;
    }
#endif
    default: {
      NS_WARNING("No backend independent TextureHost for this descriptor type");
    }
  }
  return result.forget();
}

TextureHost::TextureHost(TextureFlags aFlags)
    : AtomicRefCountedWithFinalize("TextureHost")
    , mActor(nullptr)
    , mFlags(aFlags)
    , mCompositableCount(0)
    , mFwdTransactionId(0)
{
}

TextureHost::~TextureHost()
{
  // If we still have a ReadLock, unlock it. At this point we don't care about
  // the texture client being written into on the other side since it should be
  // destroyed by now. But we will hit assertions if we don't ReadUnlock before
  // destroying the lock itself.
  ReadUnlock();
}

void TextureHost::Finalize()
{
  if (!(GetFlags() & TextureFlags::DEALLOCATE_CLIENT)) {
    DeallocateSharedData();
    DeallocateDeviceData();
  }
}

void
TextureHost::UnbindTextureSource()
{
  if (mReadLock) {
    auto compositor = GetCompositor();
    // This TextureHost is not used anymore. Since most compositor backends are
    // working asynchronously under the hood a compositor could still be using
    // this texture, so it is generally best to wait until the end of the next
    // composition before calling ReadUnlock. We ask the compositor to take care
    // of that for us.
    if (compositor) {
      compositor->UnlockAfterComposition(this);
    } else {
      // GetCompositor returned null which means no compositor can be using this
      // texture. We can ReadUnlock right away.
      ReadUnlock();
    }
  }
}

void
TextureHost::RecycleTexture(TextureFlags aFlags)
{
  MOZ_ASSERT(GetFlags() & TextureFlags::RECYCLE);
  MOZ_ASSERT(aFlags & TextureFlags::RECYCLE);
  mFlags = aFlags;
}

void
TextureHost::NotifyNotUsed()
{
  if (!mActor) {
    return;
  }

  // Do not need to call NotifyNotUsed() if TextureHost does not have
  // TextureFlags::RECYCLE flag.
  if (!(GetFlags() & TextureFlags::RECYCLE)) {
    return;
  }

  auto compositor = GetCompositor();
  // The following cases do not need to defer NotifyNotUsed until next Composite.
  // - TextureHost does not have Compositor.
  // - Compositor is BasicCompositor.
  // - TextureHost has intermediate buffer.
  //   end of buffer usage.
  if (!compositor ||
      compositor->IsDestroyed() ||
      compositor->AsBasicCompositor() ||
      HasIntermediateBuffer()) {
    static_cast<TextureParent*>(mActor)->NotifyNotUsed(mFwdTransactionId);
    return;
  }

  compositor->NotifyNotUsedAfterComposition(this);
}

void
TextureHost::CallNotifyNotUsed()
{
  if (!mActor) {
    return;
  }
  static_cast<TextureParent*>(mActor)->NotifyNotUsed(mFwdTransactionId);
}

void
TextureHost::PrintInfo(std::stringstream& aStream, const char* aPrefix)
{
  aStream << aPrefix;
  aStream << nsPrintfCString("%s (0x%p)", Name(), this).get();
  // Note: the TextureHost needs to be locked before it is safe to call
  //       GetSize() and GetFormat() on it.
  if (Lock()) {
    AppendToString(aStream, GetSize(), " [size=", "]");
    AppendToString(aStream, GetFormat(), " [format=", "]");
    Unlock();
  }
  AppendToString(aStream, mFlags, " [flags=", "]");
#ifdef MOZ_DUMP_PAINTING
  if (gfxPrefs::LayersDumpTexture() || profiler_feature_active("layersdump")) {
    nsAutoCString pfx(aPrefix);
    pfx += "  ";

    aStream << "\n" << pfx.get() << "Surface: ";
    RefPtr<gfx::DataSourceSurface> dSurf = GetAsSurface();
    if (dSurf) {
      aStream << gfxUtils::GetAsLZ4Base64Str(dSurf).get();
    }
  }
#endif
}

void
TextureHost::Updated(const nsIntRegion* aRegion)
{
    LayerScope::ContentChanged(this);
    UpdatedInternal(aRegion);
}

TextureSource::TextureSource()
: mCompositableCount(0)
{
    MOZ_COUNT_CTOR(TextureSource);
}

TextureSource::~TextureSource()
{
    MOZ_COUNT_DTOR(TextureSource);
}

const char*
TextureSource::Name() const
{
  MOZ_CRASH("GFX: TextureSource without class name");
  return "TextureSource";
}
  
BufferTextureHost::BufferTextureHost(const BufferDescriptor& aDesc,
                                     TextureFlags aFlags)
: TextureHost(aFlags)
, mCompositor(nullptr)
, mUpdateSerial(1)
, mLocked(false)
, mNeedsFullUpdate(false)
{
  mDescriptor = aDesc;
  switch (mDescriptor.type()) {
    case BufferDescriptor::TYCbCrDescriptor: {
      const YCbCrDescriptor& ycbcr = mDescriptor.get_YCbCrDescriptor();
      mSize = ycbcr.ySize();
      mFormat = gfx::SurfaceFormat::YUV;
      mHasIntermediateBuffer = ycbcr.hasIntermediateBuffer();
      break;
    }
    case BufferDescriptor::TRGBDescriptor: {
      const RGBDescriptor& rgb = mDescriptor.get_RGBDescriptor();
      mSize = rgb.size();
      mFormat = rgb.format();
      mHasIntermediateBuffer = rgb.hasIntermediateBuffer();
      break;
    }
    default:
      gfxCriticalError() << "Bad buffer host descriptor " << (int)mDescriptor.type();
      MOZ_CRASH("GFX: Bad descriptor");
  }
  if (aFlags & TextureFlags::COMPONENT_ALPHA) {
    // One texture of a component alpha texture pair will start out all white.
    // This hack allows us to easily make sure that white will be uploaded.
    // See bug 1138934
    mNeedsFullUpdate = true;
  }
}

BufferTextureHost::~BufferTextureHost()
{}

void
BufferTextureHost::UpdatedInternal(const nsIntRegion* aRegion)
{
  ++mUpdateSerial;
  // If the last frame wasn't uploaded yet, and we -don't- have a partial update,
  // we still need to update the full surface.
  if (aRegion && !mNeedsFullUpdate) {
    mMaybeUpdatedRegion.OrWith(*aRegion);
  } else {
    mNeedsFullUpdate = true;
  }
  if (GetFlags() & TextureFlags::IMMEDIATE_UPLOAD) {
    DebugOnly<bool> result = MaybeUpload(!mNeedsFullUpdate ? &mMaybeUpdatedRegion : nullptr);
    NS_WARNING_ASSERTION(result, "Failed to upload a texture");
  }
}

void
BufferTextureHost::SetCompositor(Compositor* aCompositor)
{
  MOZ_ASSERT(aCompositor);
  if (mCompositor == aCompositor) {
    return;
  }
  if (aCompositor && mCompositor &&
      aCompositor->GetBackendType() == mCompositor->GetBackendType()) {
    RefPtr<TextureSource> it = mFirstSource;
    while (it) {
      it->SetCompositor(aCompositor);
      it = it->GetNextSibling();
    }
  }
  if (mFirstSource && mFirstSource->IsOwnedBy(this)) {
    mFirstSource->SetOwner(nullptr);
  }
  if (mFirstSource) {
    mFirstSource = nullptr;
    mNeedsFullUpdate = true;
  }
  mCompositor = aCompositor;
}

void
BufferTextureHost::DeallocateDeviceData()
{
  if (mFirstSource && mFirstSource->NumCompositableRefs() > 0) {
    // WrappingTextureSourceYCbCrBasic wraps YUV format BufferTextureHost.
    // When BufferTextureHost is destroyed, data of
    // WrappingTextureSourceYCbCrBasic becomes invalid.
    if (mFirstSource->AsWrappingTextureSourceYCbCrBasic() &&
        mFirstSource->IsOwnedBy(this)) {
      mFirstSource->SetOwner(nullptr);
      mFirstSource->DeallocateDeviceData();
    }
    return;
  }

  if (!mFirstSource || !mFirstSource->IsOwnedBy(this)) {
    mFirstSource = nullptr;
    return;
  }

  mFirstSource->SetOwner(nullptr);

  RefPtr<TextureSource> it = mFirstSource;
  while (it) {
    it->DeallocateDeviceData();
    it = it->GetNextSibling();
  }
}

bool
BufferTextureHost::Lock()
{
  MOZ_ASSERT(!mLocked);
  if (!MaybeUpload(!mNeedsFullUpdate ? &mMaybeUpdatedRegion : nullptr)) {
      return false;
  }
  mLocked = !!mFirstSource;
  return mLocked;
}

void
BufferTextureHost::Unlock()
{
  MOZ_ASSERT(mLocked);
  mLocked = false;
}

void
TextureHost::DeserializeReadLock(const ReadLockDescriptor& aDesc,
                                 ISurfaceAllocator* aAllocator)
{
  RefPtr<TextureReadLock> lock = TextureReadLock::Deserialize(aDesc, aAllocator);
  if (!lock) {
    return;
  }

  // If mReadLock is not null it means we haven't unlocked it yet and the content
  // side should not have been able to write into this texture and send a new lock!
  MOZ_ASSERT(!mReadLock);
  mReadLock = lock.forget();
}

void
TextureHost::ReadUnlock()
{
  if (mReadLock) {
    mReadLock->ReadUnlock();
    mReadLock = nullptr;
  }
}

bool
BufferTextureHost::EnsureWrappingTextureSource()
{
  MOZ_ASSERT(!mHasIntermediateBuffer);

  if (mFirstSource && mFirstSource->IsOwnedBy(this)) {
    return true;
  }
  // We don't own it, apparently.
  if (mFirstSource) {
    mNeedsFullUpdate = true;
    mFirstSource = nullptr;
  }

  if (!mCompositor) {
    return false;
  }

  if (mFormat == gfx::SurfaceFormat::YUV) {
    mFirstSource = mCompositor->CreateDataTextureSourceAroundYCbCr(this);
  } else {
    RefPtr<gfx::DataSourceSurface> surf =
      gfx::Factory::CreateWrappingDataSourceSurface(GetBuffer(),
        ImageDataSerializer::ComputeRGBStride(mFormat, mSize.width), mSize, mFormat);
    if (!surf) {
      return false;
    }
    mFirstSource = mCompositor->CreateDataTextureSourceAround(surf);
  }

  if (!mFirstSource) {
    // BasicCompositor::CreateDataTextureSourceAround never returns null
    // and we don't expect to take this branch if we are using another backend.
    // Returning false is fine but if we get into this situation it probably
    // means something fishy is going on, like a texture being used with
    // several compositor backends.
    NS_WARNING("Failed to use a BufferTextureHost without intermediate buffer");
    return false;
  }

  mFirstSource->SetUpdateSerial(mUpdateSerial);
  mFirstSource->SetOwner(this);

  return true;
}

static
bool IsCompatibleTextureSource(TextureSource* aTexture,
                               const BufferDescriptor& aDescriptor,
                               Compositor* aCompositor)
{
  if (!aCompositor) {
    return false;
  }

  switch (aDescriptor.type()) {
    case BufferDescriptor::TYCbCrDescriptor: {
      const YCbCrDescriptor& ycbcr = aDescriptor.get_YCbCrDescriptor();

      if (!aCompositor->SupportsEffect(EffectTypes::YCBCR)) {
        return aTexture->GetFormat() == gfx::SurfaceFormat::B8G8R8X8
            && aTexture->GetSize() == ycbcr.ySize();
      }

      if (aTexture->GetFormat() != gfx::SurfaceFormat::A8
          || aTexture->GetSize() != ycbcr.ySize()) {
        return false;
      }

      auto cbTexture = aTexture->GetSubSource(1);
      if (!cbTexture
          || cbTexture->GetFormat() != gfx::SurfaceFormat::A8
          || cbTexture->GetSize() != ycbcr.cbCrSize()) {
        return false;
      }

      auto crTexture = aTexture->GetSubSource(2);
      if (!crTexture
          || crTexture->GetFormat() != gfx::SurfaceFormat::A8
          || crTexture->GetSize() != ycbcr.cbCrSize()) {
        return false;
      }

      return true;
    }
    case BufferDescriptor::TRGBDescriptor: {
      const RGBDescriptor& rgb = aDescriptor.get_RGBDescriptor();
      return aTexture->GetFormat() == rgb.format()
          && aTexture->GetSize() == rgb.size();
    }
    default: {
      return false;
    }
  }
}

void
BufferTextureHost::PrepareTextureSource(CompositableTextureSourceRef& aTexture)
{
  // Reuse WrappingTextureSourceYCbCrBasic to reduce memory consumption.
  if (mFormat == gfx::SurfaceFormat::YUV &&
      !mHasIntermediateBuffer &&
      aTexture.get() &&
      aTexture->AsWrappingTextureSourceYCbCrBasic() &&
      aTexture->NumCompositableRefs() <= 1 &&
      aTexture->GetSize() == GetSize()) {
    aTexture->AsSourceBasic()->SetBufferTextureHost(this);
    aTexture->AsDataTextureSource()->SetOwner(this);
    mFirstSource = aTexture->AsDataTextureSource();
    mNeedsFullUpdate = true;
  }

  if (!mHasIntermediateBuffer) {
    EnsureWrappingTextureSource();
  }

  if (mFirstSource && mFirstSource->IsOwnedBy(this)) {
    // We are already attached to a TextureSource, nothing to do except tell
    // the compositable to use it.
    aTexture = mFirstSource.get();
    return;
  }

  // We don't own it, apparently.
  if (mFirstSource) {
    mNeedsFullUpdate = true;
    mFirstSource = nullptr;
  }

  DataTextureSource* texture = aTexture.get() ? aTexture->AsDataTextureSource() : nullptr;

  bool compatibleFormats = texture && IsCompatibleTextureSource(texture,
                                                                mDescriptor,
                                                                mCompositor);

  bool shouldCreateTexture = !compatibleFormats
                           || texture->NumCompositableRefs() > 1
                           || texture->HasOwner();

  if (!shouldCreateTexture) {
    mFirstSource = texture;
    mFirstSource->SetOwner(this);
    mNeedsFullUpdate = true;

    // It's possible that texture belonged to a different compositor,
    // so make sure we update it (and all of its siblings) to the
    // current one.
    RefPtr<TextureSource> it = mFirstSource;
    while (it) {
      it->SetCompositor(mCompositor);
      it = it->GetNextSibling();
    }
  }
}

bool
BufferTextureHost::BindTextureSource(CompositableTextureSourceRef& aTexture)
{
  MOZ_ASSERT(mLocked);
  MOZ_ASSERT(mFirstSource);
  aTexture = mFirstSource;
  return !!aTexture;
}

void
BufferTextureHost::UnbindTextureSource()
{
  if (mFirstSource && mFirstSource->IsOwnedBy(this)) {
    mFirstSource->Unbind();
  }
  // This texture is not used by any layer anymore.
  // If the texture doesn't have an intermediate buffer, it means we are
  // compositing synchronously on the CPU, so we don't need to wait until
  // the end of the next composition to ReadUnlock (which other textures do
  // by default).
  // If the texture has an intermediate buffer we don't care either because
  // texture uploads are also performed synchronously for BufferTextureHost.
  ReadUnlock();
}

gfx::SurfaceFormat
BufferTextureHost::GetFormat() const
{
  // mFormat is the format of the data that we share with the content process.
  // GetFormat, on the other hand, expects the format that we present to the
  // Compositor (it is used to choose the effect type).
  // if the compositor does not support YCbCr effects, we give it a RGBX texture
  // instead (see BufferTextureHost::Upload)
  if (mFormat == gfx::SurfaceFormat::YUV &&
    mCompositor &&
    !mCompositor->SupportsEffect(EffectTypes::YCBCR)) {
    return gfx::SurfaceFormat::R8G8B8X8;
  }
  return mFormat;
}

YUVColorSpace
BufferTextureHost::GetYUVColorSpace() const
{
  if (mFormat == gfx::SurfaceFormat::YUV) {
    const YCbCrDescriptor& desc = mDescriptor.get_YCbCrDescriptor();
    return desc.yUVColorSpace();
  }
  return YUVColorSpace::UNKNOWN;
}

bool
BufferTextureHost::MaybeUpload(nsIntRegion *aRegion)
{
  auto serial = mFirstSource ? mFirstSource->GetUpdateSerial() : 0;

  if (serial == mUpdateSerial) {
    return true;
  }

  if (serial == 0) {
    // 0 means the source has no valid content
    aRegion = nullptr;
  }

  if (!Upload(aRegion)) {
    return false;
  }

  if (mHasIntermediateBuffer) {
    // We just did the texture upload, the content side can now freely write
    // into the shared buffer.
    ReadUnlock();
  }

  // We no longer have an invalid region.
  mNeedsFullUpdate = false;
  mMaybeUpdatedRegion.SetEmpty();

  // If upload returns true we know mFirstSource is not null
  mFirstSource->SetUpdateSerial(mUpdateSerial);
  return true;
}

bool
BufferTextureHost::Upload(nsIntRegion *aRegion)
{
  uint8_t* buf = GetBuffer();
  if (!buf) {
    // We don't have a buffer; a possible cause is that the IPDL actor
    // is already dead. This inevitably happens as IPDL actors can die
    // at any time, so we want to silently return in this case.
    // another possible cause is that IPDL failed to map the shmem when
    // deserializing it.
    return false;
  }
  if (!mCompositor) {
    // This can happen if we send textures to a compositable that isn't yet
    // attached to a layer.
    return false;
  }
  if (!mHasIntermediateBuffer && EnsureWrappingTextureSource()) {
    return true;
  }

  if (mFormat == gfx::SurfaceFormat::UNKNOWN) {
    NS_WARNING("BufferTextureHost: unsupported format!");
    return false;
  } else if (mFormat == gfx::SurfaceFormat::YUV) {
    const YCbCrDescriptor& desc = mDescriptor.get_YCbCrDescriptor();

    if (!mCompositor->SupportsEffect(EffectTypes::YCBCR)) {
      RefPtr<gfx::DataSourceSurface> surf =
        ImageDataSerializer::DataSourceSurfaceFromYCbCrDescriptor(buf, mDescriptor.get_YCbCrDescriptor());
      if (NS_WARN_IF(!surf)) {
        return false;
      }
      if (!mFirstSource) {
        mFirstSource = mCompositor->CreateDataTextureSource(mFlags|TextureFlags::RGB_FROM_YCBCR);
        mFirstSource->SetOwner(this);
      }
      mFirstSource->Update(surf, aRegion);
      return true;
    }

    RefPtr<DataTextureSource> srcY;
    RefPtr<DataTextureSource> srcU;
    RefPtr<DataTextureSource> srcV;
    if (!mFirstSource) {
      // We don't support BigImages for YCbCr compositing.
      srcY = mCompositor->CreateDataTextureSource(mFlags|TextureFlags::DISALLOW_BIGIMAGE);
      srcU = mCompositor->CreateDataTextureSource(mFlags|TextureFlags::DISALLOW_BIGIMAGE);
      srcV = mCompositor->CreateDataTextureSource(mFlags|TextureFlags::DISALLOW_BIGIMAGE);
      mFirstSource = srcY;
      mFirstSource->SetOwner(this);
      srcY->SetNextSibling(srcU);
      srcU->SetNextSibling(srcV);
    } else {
      // mFormat never changes so if this was created as a YCbCr host and already
      // contains a source it should already have 3 sources.
      // BufferTextureHost only uses DataTextureSources so it is safe to assume
      // all 3 sources are DataTextureSource.
      MOZ_ASSERT(mFirstSource->GetNextSibling());
      MOZ_ASSERT(mFirstSource->GetNextSibling()->GetNextSibling());
      srcY = mFirstSource;
      srcU = mFirstSource->GetNextSibling()->AsDataTextureSource();
      srcV = mFirstSource->GetNextSibling()->GetNextSibling()->AsDataTextureSource();
    }

    RefPtr<gfx::DataSourceSurface> tempY =
      gfx::Factory::CreateWrappingDataSourceSurface(ImageDataSerializer::GetYChannel(buf, desc),
                                                    desc.ySize().width,
                                                    desc.ySize(),
                                                    gfx::SurfaceFormat::A8);
    RefPtr<gfx::DataSourceSurface> tempCb =
      gfx::Factory::CreateWrappingDataSourceSurface(ImageDataSerializer::GetCbChannel(buf, desc),
                                                    desc.cbCrSize().width,
                                                    desc.cbCrSize(),
                                                    gfx::SurfaceFormat::A8);
    RefPtr<gfx::DataSourceSurface> tempCr =
      gfx::Factory::CreateWrappingDataSourceSurface(ImageDataSerializer::GetCrChannel(buf, desc),
                                                    desc.cbCrSize().width,
                                                    desc.cbCrSize(),
                                                    gfx::SurfaceFormat::A8);
    // We don't support partial updates for Y U V textures
    NS_ASSERTION(!aRegion, "Unsupported partial updates for YCbCr textures");
    if (!tempY ||
        !tempCb ||
        !tempCr ||
        !srcY->Update(tempY) ||
        !srcU->Update(tempCb) ||
        !srcV->Update(tempCr)) {
      NS_WARNING("failed to update the DataTextureSource");
      return false;
    }
  } else {
    // non-YCbCr case
    nsIntRegion* regionToUpdate = aRegion;
    if (!mFirstSource) {
      mFirstSource = mCompositor->CreateDataTextureSource(mFlags);
      mFirstSource->SetOwner(this);
      if (mFlags & TextureFlags::COMPONENT_ALPHA) {
        // Update the full region the first time for component alpha textures.
        regionToUpdate = nullptr;
      }
    }

    RefPtr<gfx::DataSourceSurface> surf =
      gfx::Factory::CreateWrappingDataSourceSurface(GetBuffer(),
        ImageDataSerializer::ComputeRGBStride(mFormat, mSize.width), mSize, mFormat);
    if (!surf) {
      return false;
    }

    if (!mFirstSource->Update(surf.get(), regionToUpdate)) {
      NS_WARNING("failed to update the DataTextureSource");
      return false;
    }
  }
  MOZ_ASSERT(mFirstSource);
  return true;
}

already_AddRefed<gfx::DataSourceSurface>
BufferTextureHost::GetAsSurface()
{
  RefPtr<gfx::DataSourceSurface> result;
  if (mFormat == gfx::SurfaceFormat::UNKNOWN) {
    NS_WARNING("BufferTextureHost: unsupported format!");
    return nullptr;
  } else if (mFormat == gfx::SurfaceFormat::YUV) {
    result = ImageDataSerializer::DataSourceSurfaceFromYCbCrDescriptor(
      GetBuffer(), mDescriptor.get_YCbCrDescriptor());
    if (NS_WARN_IF(!result)) {
      return nullptr;
    }
  } else {
    result =
      gfx::Factory::CreateWrappingDataSourceSurface(GetBuffer(),
        ImageDataSerializer::GetRGBStride(mDescriptor.get_RGBDescriptor()),
        mSize, mFormat);
  }
  return result.forget();
}

ShmemTextureHost::ShmemTextureHost(const ipc::Shmem& aShmem,
                                   const BufferDescriptor& aDesc,
                                   ISurfaceAllocator* aDeallocator,
                                   TextureFlags aFlags)
: BufferTextureHost(aDesc, aFlags)
, mDeallocator(aDeallocator)
{
  if (aShmem.IsReadable()) {
    mShmem = MakeUnique<ipc::Shmem>(aShmem);
  } else {
    // This can happen if we failed to map the shmem on this process, perhaps
    // because it was big and we didn't have enough contiguous address space
    // available, even though we did on the child process.
    // As a result this texture will be in an invalid state and Lock will
    // always fail.

    gfxCriticalNote << "Failed to create a valid ShmemTextureHost";
  }

  MOZ_COUNT_CTOR(ShmemTextureHost);
}

ShmemTextureHost::~ShmemTextureHost()
{
  MOZ_ASSERT(!mShmem || (mFlags & TextureFlags::DEALLOCATE_CLIENT),
             "Leaking our buffer");
  DeallocateDeviceData();
  MOZ_COUNT_DTOR(ShmemTextureHost);
}

void
ShmemTextureHost::DeallocateSharedData()
{
  if (mShmem) {
    MOZ_ASSERT(mDeallocator,
               "Shared memory would leak without a ISurfaceAllocator");
    mDeallocator->AsShmemAllocator()->DeallocShmem(*mShmem);
    mShmem = nullptr;
  }
}

void
ShmemTextureHost::ForgetSharedData()
{
  if (mShmem) {
    mShmem = nullptr;
  }
}

void
ShmemTextureHost::OnShutdown()
{
  mShmem = nullptr;
}

uint8_t* ShmemTextureHost::GetBuffer()
{
  return mShmem ? mShmem->get<uint8_t>() : nullptr;
}

size_t ShmemTextureHost::GetBufferSize()
{
  return mShmem ? mShmem->Size<uint8_t>() : 0;
}

MemoryTextureHost::MemoryTextureHost(uint8_t* aBuffer,
                                     const BufferDescriptor& aDesc,
                                     TextureFlags aFlags)
: BufferTextureHost(aDesc, aFlags)
, mBuffer(aBuffer)
{
  MOZ_COUNT_CTOR(MemoryTextureHost);
}

MemoryTextureHost::~MemoryTextureHost()
{
  MOZ_ASSERT(!mBuffer || (mFlags & TextureFlags::DEALLOCATE_CLIENT),
             "Leaking our buffer");
  DeallocateDeviceData();
  MOZ_COUNT_DTOR(MemoryTextureHost);
}

void
MemoryTextureHost::DeallocateSharedData()
{
  if (mBuffer) {
    GfxMemoryImageReporter::WillFree(mBuffer);
  }
  delete[] mBuffer;
  mBuffer = nullptr;
}

void
MemoryTextureHost::ForgetSharedData()
{
  mBuffer = nullptr;
}

uint8_t* MemoryTextureHost::GetBuffer()
{
  return mBuffer;
}

size_t MemoryTextureHost::GetBufferSize()
{
  // MemoryTextureHost just trusts that the buffer size is large enough to read
  // anything we need to. That's because MemoryTextureHost has to trust the buffer
  // pointer anyway, so the security model here is just that MemoryTexture's
  // are restricted to same-process clients.
  return std::numeric_limits<size_t>::max();
}

TextureParent::TextureParent(HostIPCAllocator* aSurfaceAllocator, uint64_t aSerial)
: mSurfaceAllocator(aSurfaceAllocator)
, mSerial(aSerial)
{
  MOZ_COUNT_CTOR(TextureParent);
}

TextureParent::~TextureParent()
{
  MOZ_COUNT_DTOR(TextureParent);
}

void
TextureParent::NotifyNotUsed(uint64_t aTransactionId)
{
  if (!mTextureHost) {
    return;
  }
  mSurfaceAllocator->NotifyNotUsed(this, aTransactionId);
}

bool
TextureParent::Init(const SurfaceDescriptor& aSharedData,
                    const LayersBackend& aBackend,
                    const TextureFlags& aFlags)
{
  mTextureHost = TextureHost::Create(aSharedData,
                                     mSurfaceAllocator,
                                     aBackend,
                                     aFlags);
  if (mTextureHost) {
    mTextureHost->mActor = this;
  }

  return !!mTextureHost;
}

void
TextureParent::Destroy()
{
  if (!mTextureHost) {
    return;
  }

  // ReadUnlock here to make sure the ReadLock's shmem does not outlive the
  // protocol that created it.
  mTextureHost->ReadUnlock();

  if (mTextureHost->GetFlags() & TextureFlags::DEALLOCATE_CLIENT) {
    mTextureHost->ForgetSharedData();
  }

  mTextureHost->mActor = nullptr;
  mTextureHost = nullptr;
}

void
TextureHost::ReceivedDestroy(PTextureParent* aActor)
{
  static_cast<TextureParent*>(aActor)->RecvDestroy();
}

bool
TextureParent::RecvRecycleTexture(const TextureFlags& aTextureFlags)
{
  if (!mTextureHost) {
    return true;
  }
  mTextureHost->RecycleTexture(aTextureFlags);
  return true;
}

////////////////////////////////////////////////////////////////////////////////

} // namespace layers
} // namespace mozilla