1 files changed, 826 insertions, 0 deletions

diff --git a/gfx/layers/client/TextureClient.h b/gfx/layers/client/TextureClient.h
new file mode 100644
index 000000000..d28f37cf5
--- /dev/null
+++ b/gfx/layers/client/TextureClient.h
@@ -0,0 +1,826 @@
+/* -*- 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/. */
+
+#ifndef MOZILLA_GFX_TEXTURECLIENT_H
+#define MOZILLA_GFX_TEXTURECLIENT_H
+
+#include <stddef.h>                     // for size_t
+#include <stdint.h>                     // for uint32_t, uint8_t, uint64_t
+#include "GLTextureImage.h"             // for TextureImage
+#include "ImageTypes.h"                 // for StereoMode
+#include "mozilla/Assertions.h"         // for MOZ_ASSERT, etc
+#include "mozilla/Attributes.h"         // for override
+#include "mozilla/DebugOnly.h"
+#include "mozilla/RefPtr.h"             // for RefPtr, RefCounted
+#include "mozilla/gfx/2D.h"             // for DrawTarget
+#include "mozilla/gfx/Point.h"          // for IntSize
+#include "mozilla/gfx/Types.h"          // for SurfaceFormat
+#include "mozilla/ipc/Shmem.h"          // for Shmem
+#include "mozilla/layers/AtomicRefCountedWithFinalize.h"
+#include "mozilla/layers/CompositorTypes.h"  // for TextureFlags, etc
+#include "mozilla/layers/ISurfaceAllocator.h"
+#include "mozilla/layers/LayersTypes.h"
+#include "mozilla/layers/LayersSurfaces.h"  // for SurfaceDescriptor
+#include "mozilla/mozalloc.h"           // for operator delete
+#include "mozilla/gfx/CriticalSection.h"
+#include "nsCOMPtr.h"                   // for already_AddRefed
+#include "nsISupportsImpl.h"            // for TextureImage::AddRef, etc
+#include "GfxTexturesReporter.h"
+#include "pratom.h"
+#include "nsThreadUtils.h"
+
+class gfxImageSurface;
+
+namespace mozilla {
+
+// When defined, we track which pool the tile came from and test for
+// any inconsistencies.  This can be defined in release build as well.
+#ifdef DEBUG
+#define GFX_DEBUG_TRACK_CLIENTS_IN_POOL 1
+#endif
+
+namespace layers {
+
+class AsyncTransactionWaiter;
+class BufferTextureData;
+class CompositableForwarder;
+class KnowsCompositor;
+class LayersIPCChannel;
+class CompositableClient;
+struct PlanarYCbCrData;
+class Image;
+class PTextureChild;
+class TextureChild;
+class TextureData;
+class GPUVideoTextureData;
+struct RawTextureBuffer;
+class RawYCbCrTextureBuffer;
+class TextureClient;
+class ITextureClientRecycleAllocator;
+#ifdef GFX_DEBUG_TRACK_CLIENTS_IN_POOL
+class TextureClientPool;
+#endif
+class TextureForwarder;
+class KeepAlive;
+
+/**
+ * TextureClient is the abstraction that allows us to share data between the
+ * content and the compositor side.
+ */
+
+enum TextureAllocationFlags {
+  ALLOC_DEFAULT = 0,
+  ALLOC_CLEAR_BUFFER = 1 << 1,  // Clear the buffer to whatever is best for the draw target
+  ALLOC_CLEAR_BUFFER_WHITE = 1 << 2,  // explicit all white
+  ALLOC_CLEAR_BUFFER_BLACK = 1 << 3,  // explicit all black
+  ALLOC_DISALLOW_BUFFERTEXTURECLIENT = 1 << 4,
+
+  // Allocate the texture for out-of-band content updates. This is mostly for
+  // TextureClientD3D11, which may otherwise choose D3D10 or non-KeyedMutex
+  // surfaces when used on the main thread.
+  ALLOC_FOR_OUT_OF_BAND_CONTENT = 1 << 5,
+
+  // Disable any cross-device synchronization. This is also for TextureClientD3D11,
+  // and creates a texture without KeyedMutex.
+  ALLOC_MANUAL_SYNCHRONIZATION = 1 << 6,
+
+  // The texture is going to be updated using UpdateFromSurface and needs to support
+  // that call.
+  ALLOC_UPDATE_FROM_SURFACE = 1 << 7,
+};
+
+#ifdef XP_WIN
+typedef void* SyncHandle;
+#else
+typedef uintptr_t SyncHandle;
+#endif // XP_WIN
+
+class SyncObject : public RefCounted<SyncObject>
+{
+public:
+  MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(SyncObject)
+  virtual ~SyncObject() { }
+
+  static already_AddRefed<SyncObject> CreateSyncObject(SyncHandle aHandle);
+
+  enum class SyncType {
+    D3D11,
+  };
+
+  virtual SyncType GetSyncType() = 0;
+  virtual void FinalizeFrame() = 0;
+  virtual bool IsSyncObjectValid() = 0;
+
+protected:
+  SyncObject() { }
+};
+
+/**
+ * This class may be used to asynchronously receive an update when the content
+ * drawn to this texture client is available for reading in CPU memory. This
+ * can only be used on texture clients that support draw target creation.
+ */
+class TextureReadbackSink
+{
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(TextureReadbackSink)
+public:
+  /**
+   * Callback function to implement in order to receive a DataSourceSurface
+   * containing the data read back from the texture client. This will always
+   * be called on the main thread, and this may not hold on to the
+   * DataSourceSurface beyond the execution of this function.
+   */
+  virtual void ProcessReadback(gfx::DataSourceSurface *aSourceSurface) = 0;
+
+protected:
+  virtual ~TextureReadbackSink() {}
+};
+
+enum class BackendSelector
+{
+  Content,
+  Canvas
+};
+
+/// Temporary object providing direct access to a Texture's memory.
+///
+/// see TextureClient::CanExposeMappedData() and TextureClient::BorrowMappedData().
+struct MappedTextureData
+{
+  uint8_t* data;
+  gfx::IntSize size;
+  int32_t stride;
+  gfx::SurfaceFormat format;
+};
+
+struct MappedYCbCrChannelData
+{
+  uint8_t* data;
+  gfx::IntSize size;
+  int32_t stride;
+  int32_t skip;
+
+  bool CopyInto(MappedYCbCrChannelData& aDst);
+};
+
+struct MappedYCbCrTextureData {
+  MappedYCbCrChannelData y;
+  MappedYCbCrChannelData cb;
+  MappedYCbCrChannelData cr;
+  // Sad but because of how SharedPlanarYCbCrData is used we have to expose this for now.
+  uint8_t* metadata;
+  StereoMode stereoMode;
+
+  bool CopyInto(MappedYCbCrTextureData& aDst)
+  {
+    return y.CopyInto(aDst.y)
+        && cb.CopyInto(aDst.cb)
+        && cr.CopyInto(aDst.cr);
+  }
+};
+
+class ReadLockDescriptor;
+
+// A class to help implement copy-on-write semantics for shared textures.
+//
+// A TextureClient/Host pair can opt into using a ReadLock by calling
+// TextureClient::EnableReadLock. This will equip the TextureClient with a
+// ReadLock object that will be automatically ReadLock()'ed by the texture itself
+// when it is written into (see TextureClient::Unlock).
+// A TextureReadLock's counter starts at 1 and is expected to be equal to 1 when the
+// lock is destroyed. See ShmemTextureReadLock for explanations about why we use
+// 1 instead of 0 as the initial state.
+// TextureReadLock is mostly internally managed by the TextureClient/Host pair,
+// and the compositable only has to forward it during updates. If an update message
+// contains a null_t lock, it means that the texture was not written into on the
+// content side, and there is no synchronization required on the compositor side
+// (or it means that the texture pair did not opt into using ReadLocks).
+// On the compositor side, the TextureHost can receive a ReadLock during a
+// transaction, and will both ReadUnlock() it and drop it as soon as the shared
+// data is available again for writing (the texture upload is done, or the compositor
+// not reading the texture anymore). The lock is dropped to make sure it is
+// ReadUnlock()'ed only once.
+class TextureReadLock {
+protected:
+  virtual ~TextureReadLock() {}
+
+public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(TextureReadLock)
+
+  virtual int32_t ReadLock() = 0;
+  virtual int32_t ReadUnlock() = 0;
+  virtual int32_t GetReadCount() = 0;
+  virtual bool IsValid() const = 0;
+
+  static already_AddRefed<TextureReadLock>
+  Create(LayersIPCChannel* aAllocator);
+
+  static already_AddRefed<TextureReadLock>
+  Deserialize(const ReadLockDescriptor& aDescriptor, ISurfaceAllocator* aAllocator);
+
+  virtual bool Serialize(ReadLockDescriptor& aOutput) = 0;
+
+  enum LockType {
+    TYPE_MEMORY,
+    TYPE_SHMEM
+  };
+  virtual LockType GetType() = 0;
+
+protected:
+  NS_DECL_OWNINGTHREAD
+};
+
+#ifdef XP_WIN
+class D3D11TextureData;
+#endif
+
+class TextureData {
+public:
+  struct Info {
+    gfx::IntSize size;
+    gfx::SurfaceFormat format;
+    bool hasIntermediateBuffer;
+    bool hasSynchronization;
+    bool supportsMoz2D;
+    bool canExposeMappedData;
+
+    Info()
+    : format(gfx::SurfaceFormat::UNKNOWN)
+    , hasIntermediateBuffer(false)
+    , hasSynchronization(false)
+    , supportsMoz2D(false)
+    , canExposeMappedData(false)
+    {}
+  };
+
+  TextureData() { MOZ_COUNT_CTOR(TextureData); }
+
+  virtual ~TextureData() { MOZ_COUNT_DTOR(TextureData); }
+
+  virtual void FillInfo(TextureData::Info& aInfo) const = 0;
+
+  virtual bool Lock(OpenMode aMode) = 0;
+
+  virtual void Unlock() = 0;
+
+  virtual already_AddRefed<gfx::DrawTarget> BorrowDrawTarget() { return nullptr; }
+
+  virtual bool BorrowMappedData(MappedTextureData&) { return false; }
+
+  virtual bool BorrowMappedYCbCrData(MappedYCbCrTextureData&) { return false; }
+
+  virtual void Deallocate(LayersIPCChannel* aAllocator) = 0;
+
+  /// Depending on the texture's flags either Deallocate or Forget is called.
+  virtual void Forget(LayersIPCChannel* aAllocator) {}
+
+  virtual bool Serialize(SurfaceDescriptor& aDescriptor) = 0;
+
+  virtual TextureData*
+  CreateSimilar(LayersIPCChannel* aAllocator,
+                LayersBackend aLayersBackend,
+                TextureFlags aFlags = TextureFlags::DEFAULT,
+                TextureAllocationFlags aAllocFlags = ALLOC_DEFAULT) const { return nullptr; }
+
+  virtual bool UpdateFromSurface(gfx::SourceSurface* aSurface) { return false; };
+
+  virtual bool ReadBack(TextureReadbackSink* aReadbackSink) { return false; }
+
+  virtual void SyncWithObject(SyncObject* aFence) {};
+
+  virtual TextureFlags GetTextureFlags() const { return TextureFlags::NO_FLAGS; }
+
+#ifdef XP_WIN
+  virtual D3D11TextureData* AsD3D11TextureData() {
+    return nullptr;
+  }
+#endif
+
+  virtual BufferTextureData* AsBufferTextureData() { return nullptr; }
+
+  virtual GPUVideoTextureData* AsGPUVideoTextureData() { return nullptr; }
+};
+
+/**
+ * TextureClient is a thin abstraction over texture data that need to be shared
+ * between the content process and the compositor process. It is the
+ * content-side half of a TextureClient/TextureHost pair. A corresponding
+ * TextureHost lives on the compositor-side.
+ *
+ * TextureClient's primary purpose is to present texture data in a way that is
+ * understood by the IPC system. There are two ways to use it:
+ * - Use it to serialize image data that is not IPC-friendly (most likely
+ * involving a copy into shared memory)
+ * - preallocate it and paint directly into it, which avoids copy but requires
+ * the painting code to be aware of TextureClient (or at least the underlying
+ * shared memory).
+ *
+ * There is always one and only one TextureClient per TextureHost, and the
+ * TextureClient/Host pair only owns one buffer of image data through its
+ * lifetime. This means that the lifetime of the underlying shared data
+ * matches the lifetime of the TextureClient/Host pair. It also means
+ * TextureClient/Host do not implement double buffering, which is the
+ * responsibility of the compositable (which would use two Texture pairs).
+ * In order to send several different buffers to the compositor side, use
+ * several TextureClients.
+ */
+class TextureClient
+  : public AtomicRefCountedWithFinalize<TextureClient>
+{
+public:
+  explicit TextureClient(TextureData* aData, TextureFlags aFlags, LayersIPCChannel* aAllocator);
+
+  virtual ~TextureClient();
+
+  static already_AddRefed<TextureClient>
+  CreateWithData(TextureData* aData, TextureFlags aFlags, LayersIPCChannel* aAllocator);
+
+  // Creates and allocates a TextureClient usable with Moz2D.
+  static already_AddRefed<TextureClient>
+  CreateForDrawing(KnowsCompositor* aAllocator,
+                   gfx::SurfaceFormat aFormat,
+                   gfx::IntSize aSize,
+                   BackendSelector aSelector,
+                   TextureFlags aTextureFlags,
+                   TextureAllocationFlags flags = ALLOC_DEFAULT);
+
+  static already_AddRefed<TextureClient>
+  CreateFromSurface(KnowsCompositor* aAllocator,
+                    gfx::SourceSurface* aSurface,
+                    BackendSelector aSelector,
+                    TextureFlags aTextureFlags,
+                    TextureAllocationFlags aAllocFlags);
+
+  // Creates and allocates a TextureClient supporting the YCbCr format.
+  static already_AddRefed<TextureClient>
+  CreateForYCbCr(KnowsCompositor* aAllocator,
+                 gfx::IntSize aYSize,
+                 gfx::IntSize aCbCrSize,
+                 StereoMode aStereoMode,
+                 YUVColorSpace aYUVColorSpace,
+                 TextureFlags aTextureFlags);
+
+  // Creates and allocates a TextureClient (can be accessed through raw
+  // pointers).
+  static already_AddRefed<TextureClient>
+  CreateForRawBufferAccess(KnowsCompositor* aAllocator,
+                           gfx::SurfaceFormat aFormat,
+                           gfx::IntSize aSize,
+                           gfx::BackendType aMoz2dBackend,
+                           TextureFlags aTextureFlags,
+                           TextureAllocationFlags flags = ALLOC_DEFAULT);
+
+  // Creates and allocates a TextureClient (can beaccessed through raw
+  // pointers) with a certain buffer size. It's unfortunate that we need this.
+  // providing format and sizes could let us do more optimization.
+  static already_AddRefed<TextureClient>
+  CreateForYCbCrWithBufferSize(KnowsCompositor* aAllocator,
+                               size_t aSize,
+                               YUVColorSpace aYUVColorSpace,
+                               TextureFlags aTextureFlags);
+
+  // Creates and allocates a TextureClient of the same type.
+  already_AddRefed<TextureClient>
+  CreateSimilar(LayersBackend aLayersBackend = LayersBackend::LAYERS_NONE,
+                TextureFlags aFlags = TextureFlags::DEFAULT,
+                TextureAllocationFlags aAllocFlags = ALLOC_DEFAULT) const;
+
+  /**
+   * Locks the shared data, allowing the caller to get access to it.
+   *
+   * Please always lock/unlock when accessing the shared data.
+   * If Lock() returns false, you should not attempt to access the shared data.
+   */
+  bool Lock(OpenMode aMode);
+
+  void Unlock();
+
+  bool IsLocked() const { return mIsLocked; }
+
+  gfx::IntSize GetSize() const { return mInfo.size; }
+
+  gfx::SurfaceFormat GetFormat() const { return mInfo.format; }
+
+  /**
+   * Returns true if this texture has a synchronization mechanism (mutex, fence, etc.).
+   * Textures that do not implement synchronization should be immutable or should
+   * use immediate uploads (see TextureFlags in CompositorTypes.h)
+   * Even if a texture does not implement synchronization, Lock and Unlock need
+   * to be used appropriately since the latter are also there to map/numap data.
+   */
+  bool HasSynchronization() const { return mInfo.hasSynchronization; }
+
+  /**
+   * Indicates whether the TextureClient implementation is backed by an
+   * in-memory buffer. The consequence of this is that locking the
+   * TextureClient does not contend with locking the texture on the host side.
+   */
+  bool HasIntermediateBuffer() const { return mInfo.hasIntermediateBuffer; }
+
+  bool CanExposeDrawTarget() const { return mInfo.supportsMoz2D; }
+
+  bool CanExposeMappedData() const { return mInfo.canExposeMappedData; }
+
+  /**
+   * Returns a DrawTarget to draw into the TextureClient.
+   * This function should never be called when not on the main thread!
+   *
+   * This must never be called on a TextureClient that is not sucessfully locked.
+   * When called several times within one Lock/Unlock pair, this method should
+   * return the same DrawTarget.
+   * The DrawTarget is automatically flushed by the TextureClient when the latter
+   * is unlocked, and the DrawTarget that will be returned within the next
+   * lock/unlock pair may or may not be the same object.
+   * Do not keep references to the DrawTarget outside of the lock/unlock pair.
+   *
+   * This is typically used as follows:
+   *
+   * if (!texture->Lock(OpenMode::OPEN_READ_WRITE)) {
+   *   return false;
+   * }
+   * {
+   *   // Restrict this code's scope to ensure all references to dt are gone
+   *   // when Unlock is called.
+   *   DrawTarget* dt = texture->BorrowDrawTarget();
+   *   // use the draw target ...
+   * }
+   * texture->Unlock();
+   *
+   */
+  gfx::DrawTarget* BorrowDrawTarget();
+
+  /**
+   * Similar to BorrowDrawTarget but provides direct access to the texture's bits
+   * instead of a DrawTarget.
+   */
+  bool BorrowMappedData(MappedTextureData&);
+  bool BorrowMappedYCbCrData(MappedYCbCrTextureData&);
+
+  /**
+   * This function can be used to update the contents of the TextureClient
+   * off the main thread.
+   */
+  void UpdateFromSurface(gfx::SourceSurface* aSurface);
+
+  /**
+   * This method is strictly for debugging. It causes locking and
+   * needless copies.
+   */
+  already_AddRefed<gfx::DataSourceSurface> GetAsSurface();
+
+  virtual void PrintInfo(std::stringstream& aStream, const char* aPrefix);
+
+  /**
+   * Copies a rectangle from this texture client to a position in aTarget.
+   * It is assumed that the necessary locks are in place; so this should at
+   * least have a read lock and aTarget should at least have a write lock.
+   */
+  bool CopyToTextureClient(TextureClient* aTarget,
+                           const gfx::IntRect* aRect,
+                           const gfx::IntPoint* aPoint);
+
+  /**
+   * Allocate and deallocate a TextureChild actor.
+   *
+   * TextureChild is an implementation detail of TextureClient that is not
+   * exposed to the rest of the code base. CreateIPDLActor and DestroyIPDLActor
+   * are for use with the managing IPDL protocols only (so that they can
+   * implement AllocPextureChild and DeallocPTextureChild).
+   */
+  static PTextureChild* CreateIPDLActor();
+  static bool DestroyIPDLActor(PTextureChild* actor);
+
+  /**
+   * Get the TextureClient corresponding to the actor passed in parameter.
+   */
+  static already_AddRefed<TextureClient> AsTextureClient(PTextureChild* actor);
+
+  /**
+   * TextureFlags contain important information about various aspects
+   * of the texture, like how its liferime is managed, and how it
+   * should be displayed.
+   * See TextureFlags in CompositorTypes.h.
+   */
+  TextureFlags GetFlags() const { return mFlags; }
+
+  bool HasFlags(TextureFlags aFlags) const
+  {
+    return (mFlags & aFlags) == aFlags;
+  }
+
+  void AddFlags(TextureFlags aFlags);
+
+  void RemoveFlags(TextureFlags aFlags);
+
+  // Must not be called when TextureClient is in use by CompositableClient.
+  void RecycleTexture(TextureFlags aFlags);
+
+  /**
+   * After being shared with the compositor side, an immutable texture is never
+   * modified, it can only be read. It is safe to not Lock/Unlock immutable
+   * textures.
+   */
+  bool IsImmutable() const { return !!(mFlags & TextureFlags::IMMUTABLE); }
+
+  void MarkImmutable() { AddFlags(TextureFlags::IMMUTABLE); }
+
+  bool IsSharedWithCompositor() const;
+
+  /**
+   * If this method returns false users of TextureClient are not allowed
+   * to access the shared data.
+   */
+  bool IsValid() const { return !!mData; }
+
+  /**
+   * Called when TextureClient is added to CompositableClient.
+   */
+  void SetAddedToCompositableClient();
+
+  /**
+   * If this method retuns false, TextureClient is already added to CompositableClient,
+   * since its creation or recycling.
+   */
+  bool IsAddedToCompositableClient() const { return mAddedToCompositableClient; }
+
+  /**
+  * Create and init the TextureChild/Parent IPDL actor pair
+  * with a CompositableForwarder.
+  *
+  * Should be called only once per TextureClient.
+  * The TextureClient must not be locked when calling this method.
+  */
+  bool InitIPDLActor(CompositableForwarder* aForwarder);
+
+  /**
+   * Create and init the TextureChild/Parent IPDL actor pair
+   * with a TextureForwarder.
+   *
+   * Should be called only once per TextureClient.
+   * The TextureClient must not be locked when calling this method.
+   */
+  bool InitIPDLActor(KnowsCompositor* aForwarder);
+
+  /**
+   * Return a pointer to the IPDLActor.
+   *
+   * This is to be used with IPDL messages only. Do not store the returned
+   * pointer.
+   */
+  PTextureChild* GetIPDLActor();
+
+  /**
+   * Triggers the destruction of the shared data and the corresponding TextureHost.
+   *
+   * If the texture flags contain TextureFlags::DEALLOCATE_CLIENT, the destruction
+   * will be synchronously coordinated with the compositor side, otherwise it
+   * will be done asynchronously.
+   * If sync is true, the destruction will be synchronous regardless of the
+   * texture's flags (bad for performance, use with care).
+   */
+  void Destroy(bool sync = false);
+
+  /**
+   * Track how much of this texture is wasted.
+   * For example we might allocate a 256x256 tile but only use 10x10.
+   */
+  void SetWaste(int aWasteArea) {
+    mWasteTracker.Update(aWasteArea, BytesPerPixel(GetFormat()));
+  }
+
+  /**
+   * This sets the readback sink that this texture is to use. This will
+   * receive the data for this texture as soon as it becomes available after
+   * texture unlock.
+   */
+  virtual void SetReadbackSink(TextureReadbackSink* aReadbackSink) {
+    mReadbackSink = aReadbackSink;
+  }
+
+  void SyncWithObject(SyncObject* aFence) { mData->SyncWithObject(aFence); }
+
+  LayersIPCChannel* GetAllocator() { return mAllocator; }
+
+  ITextureClientRecycleAllocator* GetRecycleAllocator() { return mRecycleAllocator; }
+  void SetRecycleAllocator(ITextureClientRecycleAllocator* aAllocator);
+
+  /// If you add new code that uses this method, you are probably doing something wrong.
+  TextureData* GetInternalData() { return mData; }
+  const TextureData* GetInternalData() const { return mData; }
+
+  uint64_t GetSerial() const { return mSerial; }
+
+  void CancelWaitForRecycle();
+
+  /**
+   * Set last transaction id of CompositableForwarder.
+   * 
+   * Called when TextureClient has TextureFlags::RECYCLE flag.
+   * When CompositableForwarder forwards the TextureClient with
+   * TextureFlags::RECYCLE, it holds TextureClient's ref until host side
+   * releases it. The host side sends TextureClient release message.
+   * The id is used to check if the message is for the last TextureClient
+   * forwarding.
+   */
+  void SetLastFwdTransactionId(uint64_t aTransactionId)
+  {
+    MOZ_ASSERT(mFwdTransactionId <= aTransactionId);
+    mFwdTransactionId = aTransactionId;
+  }
+
+  uint64_t GetLastFwdTransactionId() { return mFwdTransactionId; }
+
+  void EnableReadLock();
+
+  TextureReadLock* GetReadLock() { return mReadLock; }
+
+  bool IsReadLocked() const;
+
+  void SerializeReadLock(ReadLockDescriptor& aDescriptor);
+
+private:
+  static void TextureClientRecycleCallback(TextureClient* aClient, void* aClosure);
+ 
+  // Internal helpers for creating texture clients using the actual forwarder instead
+  // of KnowsCompositor. TextureClientPool uses these to let it cache texture clients
+  // per-process instead of per ShadowLayerForwarder, but everyone else should
+  // use the public functions instead.
+  friend class TextureClientPool;
+  static already_AddRefed<TextureClient>
+  CreateForDrawing(TextureForwarder* aAllocator,
+                   gfx::SurfaceFormat aFormat,
+                   gfx::IntSize aSize,
+                   LayersBackend aLayersBackend,
+                   int32_t aMaxTextureSize,
+                   BackendSelector aSelector,
+                   TextureFlags aTextureFlags,
+                   TextureAllocationFlags aAllocFlags = ALLOC_DEFAULT);
+  
+  static already_AddRefed<TextureClient>
+  CreateForRawBufferAccess(LayersIPCChannel* aAllocator,
+                           gfx::SurfaceFormat aFormat,
+                           gfx::IntSize aSize,
+                           gfx::BackendType aMoz2dBackend,
+                           LayersBackend aLayersBackend,
+                           TextureFlags aTextureFlags,
+                           TextureAllocationFlags flags = ALLOC_DEFAULT);
+
+  /**
+   * Called once, during the destruction of the Texture, on the thread in which
+   * texture's reference count reaches 0 (could be any thread).
+   *
+   * Here goes the shut-down code that uses virtual methods.
+   * Must only be called by Release().
+   */
+  void Finalize() {}
+
+  friend class AtomicRefCountedWithFinalize<TextureClient>;
+protected:
+  /**
+   * Should only be called *once* per texture, in TextureClient::InitIPDLActor.
+   * Some texture implementations rely on the fact that the descriptor will be
+   * deserialized.
+   * Calling ToSurfaceDescriptor again after it has already returned true,
+   * or never constructing a TextureHost with aDescriptor may result in a memory
+   * leak (see TextureClientD3D9 for example).
+   */
+  bool ToSurfaceDescriptor(SurfaceDescriptor& aDescriptor);
+
+  void LockActor() const;
+  void UnlockActor() const;
+
+  TextureData::Info mInfo;
+
+  RefPtr<LayersIPCChannel> mAllocator;
+  RefPtr<TextureChild> mActor;
+  RefPtr<ITextureClientRecycleAllocator> mRecycleAllocator;
+  RefPtr<TextureReadLock> mReadLock;
+
+  TextureData* mData;
+  RefPtr<gfx::DrawTarget> mBorrowedDrawTarget;
+
+  TextureFlags mFlags;
+
+  gl::GfxTextureWasteTracker mWasteTracker;
+
+  OpenMode mOpenMode;
+#ifdef DEBUG
+  uint32_t mExpectedDtRefs;
+#endif
+  bool mIsLocked;
+  // This member tracks that the texture was written into until the update
+  // is sent to the compositor. We need this remember to lock mReadLock on
+  // behalf of the compositor just before sending the notification.
+  bool mUpdated;
+
+  // Used when TextureClient is recycled with TextureFlags::RECYCLE flag.
+  bool mAddedToCompositableClient;
+
+  bool mWorkaroundAnnoyingSharedSurfaceLifetimeIssues;
+  bool mWorkaroundAnnoyingSharedSurfaceOwnershipIssues;
+
+  RefPtr<TextureReadbackSink> mReadbackSink;
+
+  uint64_t mFwdTransactionId;
+
+  // Serial id of TextureClient. It is unique in current process.
+  const uint64_t mSerial;
+  // Used to assign serial ids of TextureClient.
+  static mozilla::Atomic<uint64_t> sSerialCounter;
+
+  friend class TextureChild;
+  friend void TestTextureClientSurface(TextureClient*, gfxImageSurface*);
+  friend void TestTextureClientYCbCr(TextureClient*, PlanarYCbCrData&);
+
+#ifdef GFX_DEBUG_TRACK_CLIENTS_IN_POOL
+public:
+  // Pointer to the pool this tile came from.
+  TextureClientPool* mPoolTracker;
+#endif
+};
+
+/**
+ * Task that releases TextureClient pointer on a specified thread.
+ */
+class TextureClientReleaseTask : public Runnable
+{
+public:
+    explicit TextureClientReleaseTask(TextureClient* aClient)
+        : mTextureClient(aClient) {
+    }
+
+    NS_IMETHOD Run() override
+    {
+        mTextureClient = nullptr;
+        return NS_OK;
+    }
+
+private:
+    RefPtr<TextureClient> mTextureClient;
+};
+
+// Automatically lock and unlock a texture. Since texture locking is fallible,
+// Succeeded() must be checked on the guard object before proceeding.
+class MOZ_RAII TextureClientAutoLock
+{
+  MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER;
+
+public:
+  TextureClientAutoLock(TextureClient* aTexture, OpenMode aMode
+                        MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
+   : mTexture(aTexture),
+     mSucceeded(false)
+  {
+    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
+
+    mSucceeded = mTexture->Lock(aMode);
+#ifdef DEBUG
+    mChecked = false;
+#endif
+  }
+  ~TextureClientAutoLock() {
+    MOZ_ASSERT(mChecked);
+    if (mSucceeded) {
+      mTexture->Unlock();
+    }
+  }
+
+  bool Succeeded() {
+#ifdef DEBUG
+    mChecked = true;
+#endif
+    return mSucceeded;
+  }
+
+private:
+  TextureClient* mTexture;
+#ifdef DEBUG
+  bool mChecked;
+#endif
+  bool mSucceeded;
+};
+
+class KeepAlive
+{
+public:
+  virtual ~KeepAlive() {}
+};
+
+template<typename T>
+class TKeepAlive : public KeepAlive
+{
+public:
+  explicit TKeepAlive(T* aData) : mData(aData) {}
+protected:
+  RefPtr<T> mData;
+};
+
+/// Convenience function to set the content of ycbcr texture.
+bool UpdateYCbCrTextureClient(TextureClient* aTexture, const PlanarYCbCrData& aData);
+
+} // namespace layers
+} // namespace mozilla
+
+#endif