1 files changed, 484 insertions, 0 deletions
diff --git a/gfx/layers/wr/IpcResourceUpdateQueue.cpp b/gfx/layers/wr/IpcResourceUpdateQueue.cpp
new file mode 100644
index 0000000000..d19dc7f2f9
--- /dev/null
+++ b/gfx/layers/wr/IpcResourceUpdateQueue.cpp
@@ -0,0 +1,484 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "IpcResourceUpdateQueue.h"
+#include <string.h>
+#include <algorithm>
+#include "mozilla/Maybe.h"
+#include "mozilla/ipc/SharedMemory.h"
+#include "mozilla/layers/PTextureChild.h"
+#include "mozilla/layers/WebRenderBridgeChild.h"
+
+namespace mozilla {
+namespace wr {
+
+using namespace mozilla::layers;
+
+ShmSegmentsWriter::ShmSegmentsWriter(layers::WebRenderBridgeChild* aAllocator,
+                                     size_t aChunkSize)
+    : mShmAllocator(aAllocator), mCursor(0), mChunkSize(aChunkSize) {
+  MOZ_ASSERT(mShmAllocator);
+}
+
+ShmSegmentsWriter::~ShmSegmentsWriter() { Clear(); }
+
+ShmSegmentsWriter::ShmSegmentsWriter(ShmSegmentsWriter&& aOther) noexcept
+    : mSmallAllocs(std::move(aOther.mSmallAllocs)),
+      mLargeAllocs(std::move(aOther.mLargeAllocs)),
+      mShmAllocator(aOther.mShmAllocator),
+      mCursor(aOther.mCursor),
+      mChunkSize(aOther.mChunkSize) {
+  aOther.mCursor = 0;
+}
+
+ShmSegmentsWriter& ShmSegmentsWriter::operator=(
+    ShmSegmentsWriter&& aOther) noexcept {
+  MOZ_ASSERT(IsEmpty(), "Will forget existing updates!");
+  Clear();
+  mSmallAllocs = std::move(aOther.mSmallAllocs);
+  mLargeAllocs = std::move(aOther.mLargeAllocs);
+  mShmAllocator = aOther.mShmAllocator;
+  mCursor = aOther.mCursor;
+  mChunkSize = aOther.mChunkSize;
+  aOther.mCursor = 0;
+  return *this;
+}
+
+layers::OffsetRange ShmSegmentsWriter::Write(Range<uint8_t> aBytes) {
+  const size_t start = mCursor;
+  const size_t length = aBytes.length();
+
+  if (length >= mChunkSize * 4) {
+    auto range = AllocLargeChunk(length);
+    if (range.length()) {
+      // Allocation was successful
+      uint8_t* dstPtr = mLargeAllocs.LastElement().get<uint8_t>();
+      memcpy(dstPtr, aBytes.begin().get(), length);
+    }
+    return range;
+  }
+
+  int remainingBytesToCopy = length;
+
+  size_t srcCursor = 0;
+  size_t dstCursor = mCursor;
+  size_t currAllocLen = mSmallAllocs.Length();
+
+  while (remainingBytesToCopy > 0) {
+    if (dstCursor >= mSmallAllocs.Length() * mChunkSize) {
+      if (!AllocChunk()) {
+        // Allocation failed, so roll back to the state at the start of this
+        // Write() call and abort.
+        while (mSmallAllocs.Length() > currAllocLen) {
+          RefCountedShmem shm = mSmallAllocs.PopLastElement();
+          RefCountedShm::Dealloc(mShmAllocator, shm);
+        }
+        MOZ_ASSERT(mSmallAllocs.Length() == currAllocLen);
+        return layers::OffsetRange(0, start, 0);
+      }
+      // Allocation succeeded, so dstCursor should now be pointing to
+      // something inside the allocation buffer
+      MOZ_ASSERT(dstCursor < (mSmallAllocs.Length() * mChunkSize));
+    }
+
+    const size_t dstMaxOffset = mChunkSize * mSmallAllocs.Length();
+    const size_t dstBaseOffset = mChunkSize * (mSmallAllocs.Length() - 1);
+
+    MOZ_ASSERT(dstCursor >= dstBaseOffset);
+    MOZ_ASSERT(dstCursor <= dstMaxOffset);
+
+    size_t availableRange = dstMaxOffset - dstCursor;
+    size_t copyRange = std::min<int>(availableRange, remainingBytesToCopy);
+
+    uint8_t* srcPtr = &aBytes[srcCursor];
+    uint8_t* dstPtr = RefCountedShm::GetBytes(mSmallAllocs.LastElement()) +
+                      (dstCursor - dstBaseOffset);
+
+    memcpy(dstPtr, srcPtr, copyRange);
+
+    srcCursor += copyRange;
+    dstCursor += copyRange;
+    remainingBytesToCopy -= copyRange;
+
+    // sanity check
+    MOZ_ASSERT(remainingBytesToCopy >= 0);
+  }
+
+  mCursor += length;
+
+  return layers::OffsetRange(0, start, length);
+}
+
+bool ShmSegmentsWriter::AllocChunk() {
+  RefCountedShmem shm;
+  if (!mShmAllocator->AllocResourceShmem(mChunkSize, shm)) {
+    gfxCriticalNote << "ShmSegmentsWriter failed to allocate chunk #"
+                    << mSmallAllocs.Length();
+    MOZ_ASSERT(false, "ShmSegmentsWriter fails to allocate chunk");
+    return false;
+  }
+  RefCountedShm::AddRef(shm);
+  mSmallAllocs.AppendElement(shm);
+  return true;
+}
+
+layers::OffsetRange ShmSegmentsWriter::AllocLargeChunk(size_t aSize) {
+  ipc::Shmem shm;
+  if (!mShmAllocator->AllocShmem(aSize, &shm)) {
+    gfxCriticalNote
+        << "ShmSegmentsWriter failed to allocate large chunk of size " << aSize;
+    MOZ_ASSERT(false, "ShmSegmentsWriter fails to allocate large chunk");
+    return layers::OffsetRange(0, 0, 0);
+  }
+  mLargeAllocs.AppendElement(shm);
+
+  return layers::OffsetRange(mLargeAllocs.Length(), 0, aSize);
+}
+
+void ShmSegmentsWriter::Flush(nsTArray<RefCountedShmem>& aSmallAllocs,
+                              nsTArray<ipc::Shmem>& aLargeAllocs) {
+  MOZ_ASSERT(aSmallAllocs.IsEmpty());
+  MOZ_ASSERT(aLargeAllocs.IsEmpty());
+  aSmallAllocs = std::move(mSmallAllocs);
+  aLargeAllocs = std::move(mLargeAllocs);
+  mCursor = 0;
+}
+
+bool ShmSegmentsWriter::IsEmpty() const { return mCursor == 0; }
+
+void ShmSegmentsWriter::Clear() {
+  if (mShmAllocator) {
+    IpcResourceUpdateQueue::ReleaseShmems(mShmAllocator, mSmallAllocs);
+    IpcResourceUpdateQueue::ReleaseShmems(mShmAllocator, mLargeAllocs);
+  }
+  mCursor = 0;
+}
+
+ShmSegmentsReader::ShmSegmentsReader(
+    const nsTArray<RefCountedShmem>& aSmallShmems,
+    const nsTArray<ipc::Shmem>& aLargeShmems)
+    : mSmallAllocs(aSmallShmems), mLargeAllocs(aLargeShmems), mChunkSize(0) {
+  if (mSmallAllocs.IsEmpty()) {
+    return;
+  }
+
+  mChunkSize = RefCountedShm::GetSize(mSmallAllocs[0]);
+
+  // Check that all shmems are readable and have the same size. If anything
+  // isn't right, set mChunkSize to zero which signifies that the reader is
+  // in an invalid state and Read calls will return false;
+  for (const auto& shm : mSmallAllocs) {
+    if (!RefCountedShm::IsValid(shm) ||
+        RefCountedShm::GetSize(shm) != mChunkSize ||
+        RefCountedShm::GetBytes(shm) == nullptr) {
+      mChunkSize = 0;
+      return;
+    }
+  }
+
+  for (const auto& shm : mLargeAllocs) {
+    if (!shm.IsReadable() || shm.get<uint8_t>() == nullptr) {
+      mChunkSize = 0;
+      return;
+    }
+  }
+}
+
+bool ShmSegmentsReader::ReadLarge(const layers::OffsetRange& aRange,
+                                  wr::Vec<uint8_t>& aInto) {
+  // source = zero is for small allocs.
+  MOZ_RELEASE_ASSERT(aRange.source() != 0);
+  if (aRange.source() > mLargeAllocs.Length()) {
+    return false;
+  }
+  size_t id = aRange.source() - 1;
+  const ipc::Shmem& shm = mLargeAllocs[id];
+  if (shm.Size<uint8_t>() < aRange.length()) {
+    return false;
+  }
+
+  uint8_t* srcPtr = shm.get<uint8_t>();
+  aInto.PushBytes(Range<uint8_t>(srcPtr, aRange.length()));
+
+  return true;
+}
+
+bool ShmSegmentsReader::Read(const layers::OffsetRange& aRange,
+                             wr::Vec<uint8_t>& aInto) {
+  if (aRange.length() == 0) {
+    return true;
+  }
+
+  if (aRange.source() != 0) {
+    return ReadLarge(aRange, aInto);
+  }
+
+  if (mChunkSize == 0) {
+    return false;
+  }
+
+  if (aRange.start() + aRange.length() > mChunkSize * mSmallAllocs.Length()) {
+    return false;
+  }
+
+  size_t initialLength = aInto.Length();
+
+  size_t srcCursor = aRange.start();
+  size_t remainingBytesToCopy = aRange.length();
+  while (remainingBytesToCopy > 0) {
+    const size_t shm_idx = srcCursor / mChunkSize;
+    const size_t ptrOffset = srcCursor % mChunkSize;
+    const size_t copyRange =
+        std::min(remainingBytesToCopy, mChunkSize - ptrOffset);
+    uint8_t* srcPtr =
+        RefCountedShm::GetBytes(mSmallAllocs[shm_idx]) + ptrOffset;
+
+    aInto.PushBytes(Range<uint8_t>(srcPtr, copyRange));
+
+    srcCursor += copyRange;
+    remainingBytesToCopy -= copyRange;
+  }
+
+  return aInto.Length() - initialLength == aRange.length();
+}
+
+Maybe<Range<uint8_t>> ShmSegmentsReader::GetReadPointerLarge(
+    const layers::OffsetRange& aRange) {
+  // source = zero is for small allocs.
+  MOZ_RELEASE_ASSERT(aRange.source() != 0);
+  if (aRange.source() > mLargeAllocs.Length()) {
+    return Nothing();
+  }
+  size_t id = aRange.source() - 1;
+  const ipc::Shmem& shm = mLargeAllocs[id];
+  if (shm.Size<uint8_t>() < aRange.length()) {
+    return Nothing();
+  }
+
+  uint8_t* srcPtr = shm.get<uint8_t>();
+  return Some(Range<uint8_t>(srcPtr, aRange.length()));
+}
+
+Maybe<Range<uint8_t>> ShmSegmentsReader::GetReadPointer(
+    const layers::OffsetRange& aRange) {
+  if (aRange.length() == 0) {
+    return Some(Range<uint8_t>());
+  }
+
+  if (aRange.source() != 0) {
+    return GetReadPointerLarge(aRange);
+  }
+
+  if (mChunkSize == 0 ||
+      aRange.start() + aRange.length() > mChunkSize * mSmallAllocs.Length()) {
+    return Nothing();
+  }
+
+  size_t srcCursor = aRange.start();
+  size_t remainingBytesToCopy = aRange.length();
+  const size_t shm_idx = srcCursor / mChunkSize;
+  const size_t ptrOffset = srcCursor % mChunkSize;
+  // Return nothing if we can't return a pointer to the full range
+  if (mChunkSize - ptrOffset < remainingBytesToCopy) {
+    return Nothing();
+  }
+  uint8_t* srcPtr = RefCountedShm::GetBytes(mSmallAllocs[shm_idx]) + ptrOffset;
+  return Some(Range<uint8_t>(srcPtr, remainingBytesToCopy));
+}
+
+IpcResourceUpdateQueue::IpcResourceUpdateQueue(
+    layers::WebRenderBridgeChild* aAllocator, size_t aChunkSize)
+    : mWriter(aAllocator, aChunkSize) {}
+
+IpcResourceUpdateQueue::IpcResourceUpdateQueue(
+    IpcResourceUpdateQueue&& aOther) noexcept
+    : mWriter(std::move(aOther.mWriter)),
+      mUpdates(std::move(aOther.mUpdates)) {}
+
+IpcResourceUpdateQueue& IpcResourceUpdateQueue::operator=(
+    IpcResourceUpdateQueue&& aOther) noexcept {
+  MOZ_ASSERT(IsEmpty(), "Will forget existing updates!");
+  mWriter = std::move(aOther.mWriter);
+  mUpdates = std::move(aOther.mUpdates);
+  return *this;
+}
+
+void IpcResourceUpdateQueue::ReplaceResources(IpcResourceUpdateQueue&& aOther) {
+  MOZ_ASSERT(IsEmpty(), "Will forget existing updates!");
+  mWriter = std::move(aOther.mWriter);
+  mUpdates = std::move(aOther.mUpdates);
+}
+
+bool IpcResourceUpdateQueue::AddImage(ImageKey key,
+                                      const ImageDescriptor& aDescriptor,
+                                      Range<uint8_t> aBytes) {
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(layers::OpAddImage(aDescriptor, bytes, 0, key));
+  return true;
+}
+
+bool IpcResourceUpdateQueue::AddBlobImage(BlobImageKey key,
+                                          const ImageDescriptor& aDescriptor,
+                                          Range<uint8_t> aBytes,
+                                          ImageIntRect aVisibleRect) {
+  MOZ_RELEASE_ASSERT(aDescriptor.width > 0 && aDescriptor.height > 0);
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(
+      layers::OpAddBlobImage(aDescriptor, bytes, aVisibleRect, 0, key));
+  return true;
+}
+
+void IpcResourceUpdateQueue::AddSharedExternalImage(wr::ExternalImageId aExtId,
+                                                    wr::ImageKey aKey) {
+  mUpdates.AppendElement(layers::OpAddSharedExternalImage(aExtId, aKey));
+}
+
+void IpcResourceUpdateQueue::PushExternalImageForTexture(
+    wr::ExternalImageId aExtId, wr::ImageKey aKey,
+    layers::TextureClient* aTexture, bool aIsUpdate) {
+  MOZ_ASSERT(aTexture);
+  MOZ_ASSERT(aTexture->GetIPDLActor());
+  MOZ_RELEASE_ASSERT(aTexture->GetIPDLActor()->GetIPCChannel() ==
+                     mWriter.WrBridge()->GetIPCChannel());
+  mUpdates.AppendElement(layers::OpPushExternalImageForTexture(
+      aExtId, aKey, WrapNotNull(aTexture->GetIPDLActor()), aIsUpdate));
+}
+
+bool IpcResourceUpdateQueue::UpdateImageBuffer(
+    ImageKey aKey, const ImageDescriptor& aDescriptor, Range<uint8_t> aBytes) {
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(layers::OpUpdateImage(aDescriptor, bytes, aKey));
+  return true;
+}
+
+bool IpcResourceUpdateQueue::UpdateBlobImage(BlobImageKey aKey,
+                                             const ImageDescriptor& aDescriptor,
+                                             Range<uint8_t> aBytes,
+                                             ImageIntRect aVisibleRect,
+                                             ImageIntRect aDirtyRect) {
+  MOZ_ASSERT(aVisibleRect.width > 0 && aVisibleRect.height > 0);
+
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(layers::OpUpdateBlobImage(aDescriptor, bytes, aKey,
+                                                   aVisibleRect, aDirtyRect));
+  return true;
+}
+
+void IpcResourceUpdateQueue::UpdateSharedExternalImage(
+    wr::ExternalImageId aExtId, wr::ImageKey aKey, ImageIntRect aDirtyRect) {
+  mUpdates.AppendElement(
+      layers::OpUpdateSharedExternalImage(aExtId, aKey, aDirtyRect));
+}
+
+void IpcResourceUpdateQueue::SetBlobImageVisibleArea(
+    wr::BlobImageKey aKey, const ImageIntRect& aArea) {
+  mUpdates.AppendElement(layers::OpSetBlobImageVisibleArea(aArea, aKey));
+}
+
+void IpcResourceUpdateQueue::DeleteImage(ImageKey aKey) {
+  mUpdates.AppendElement(layers::OpDeleteImage(aKey));
+}
+
+void IpcResourceUpdateQueue::DeleteBlobImage(BlobImageKey aKey) {
+  mUpdates.AppendElement(layers::OpDeleteBlobImage(aKey));
+}
+
+bool IpcResourceUpdateQueue::AddRawFont(wr::FontKey aKey, Range<uint8_t> aBytes,
+                                        uint32_t aIndex) {
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(layers::OpAddRawFont(bytes, aIndex, aKey));
+  return true;
+}
+
+bool IpcResourceUpdateQueue::AddFontDescriptor(wr::FontKey aKey,
+                                               Range<uint8_t> aBytes,
+                                               uint32_t aIndex) {
+  auto bytes = mWriter.Write(aBytes);
+  if (!bytes.length()) {
+    return false;
+  }
+  mUpdates.AppendElement(layers::OpAddFontDescriptor(bytes, aIndex, aKey));
+  return true;
+}
+
+void IpcResourceUpdateQueue::DeleteFont(wr::FontKey aKey) {
+  mUpdates.AppendElement(layers::OpDeleteFont(aKey));
+}
+
+void IpcResourceUpdateQueue::AddFontInstance(
+    wr::FontInstanceKey aKey, wr::FontKey aFontKey, float aGlyphSize,
+    const wr::FontInstanceOptions* aOptions,
+    const wr::FontInstancePlatformOptions* aPlatformOptions,
+    Range<const gfx::FontVariation> aVariations) {
+  auto bytes = mWriter.WriteAsBytes(aVariations);
+  mUpdates.AppendElement(layers::OpAddFontInstance(
+      aOptions ? Some(*aOptions) : Nothing(),
+      aPlatformOptions ? Some(*aPlatformOptions) : Nothing(), bytes, aKey,
+      aFontKey, aGlyphSize));
+}
+
+void IpcResourceUpdateQueue::DeleteFontInstance(wr::FontInstanceKey aKey) {
+  mUpdates.AppendElement(layers::OpDeleteFontInstance(aKey));
+}
+
+void IpcResourceUpdateQueue::Flush(
+    nsTArray<layers::OpUpdateResource>& aUpdates,
+    nsTArray<layers::RefCountedShmem>& aSmallAllocs,
+    nsTArray<ipc::Shmem>& aLargeAllocs) {
+  aUpdates = std::move(mUpdates);
+  mWriter.Flush(aSmallAllocs, aLargeAllocs);
+}
+
+bool IpcResourceUpdateQueue::IsEmpty() const {
+  if (mUpdates.Length() == 0) {
+    MOZ_ASSERT(mWriter.IsEmpty());
+    return true;
+  }
+  return false;
+}
+
+void IpcResourceUpdateQueue::Clear() {
+  mWriter.Clear();
+  mUpdates.Clear();
+}
+
+// static
+void IpcResourceUpdateQueue::ReleaseShmems(
+    ipc::IProtocol* aShmAllocator, nsTArray<layers::RefCountedShmem>& aShms) {
+  for (auto& shm : aShms) {
+    if (RefCountedShm::IsValid(shm) && RefCountedShm::Release(shm) == 0) {
+      RefCountedShm::Dealloc(aShmAllocator, shm);
+    }
+  }
+  aShms.Clear();
+}
+
+// static
+void IpcResourceUpdateQueue::ReleaseShmems(ipc::IProtocol* aShmAllocator,
+                                           nsTArray<ipc::Shmem>& aShms) {
+  for (auto& shm : aShms) {
+    aShmAllocator->DeallocShmem(shm);
+  }
+  aShms.Clear();
+}
+
+}  // namespace wr
+}  // namespace mozilla