Add PERSISTENT_MAP usage for GpuMemoryBuffers.

content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc

Index: content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc
diff --git a/content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc b/content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc
index 94046f1cf15cbc09d4e95e51149342423fdb161b..a3ed45fc4d38a7293473e1446ed04732c0ad2934 100644
--- a/content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc
+++ b/content/common/gpu/client/gpu_memory_buffer_impl_unittest.cc
@@ -79,7 +79,8 @@ TEST_P(GpuMemoryBufferImplTest, CreateFromHandle) {
 TEST_P(GpuMemoryBufferImplTest, Map) {
   const int kBufferId = 1;
 
-  gfx::Size buffer_size(2, 2);
+  // Use a multiple of 4 for both dimensions to support compressed formats.
+  gfx::Size buffer_size(4, 4);
 
   for (auto configuration : supported_configurations_) {
     if (configuration.usage != gfx::GpuMemoryBuffer::MAP)
@@ -138,6 +139,95 @@ TEST_P(GpuMemoryBufferImplTest, Map) {
   }
 }
 
+TEST_P(GpuMemoryBufferImplTest, PersistentMap) {
+  const int kBufferId = 1;
+
+  // Use a multiple of 4 for both dimensions to support compressed formats.
+  gfx::Size buffer_size(4, 4);
+
+  for (auto configuration : supported_configurations_) {
+    if (configuration.usage != gfx::GpuMemoryBuffer::PERSISTENT_MAP)
+      continue;
+
+    scoped_ptr<GpuMemoryBufferImpl> buffer(
+        GpuMemoryBufferImpl::CreateFromHandle(
+            CreateGpuMemoryBuffer(kBufferId, buffer_size, configuration.format,
+                                  configuration.usage),
+            buffer_size, configuration.format,
+            base::Bind(&GpuMemoryBufferImplTest::DestroyGpuMemoryBuffer,
+                       base::Unretained(this), kBufferId)));
+    ASSERT_TRUE(buffer);
+    EXPECT_FALSE(buffer->IsMapped());
+
+    size_t num_planes =
+        GpuMemoryBufferImpl::NumberOfPlanesForGpuMemoryBufferFormat(
+            configuration.format);
+
+    // Map buffer into user space.
+    scoped_ptr<void* []> mapped_buffers(new void* [num_planes]);
+    bool rv = buffer->Map(mapped_buffers.get());
+    ASSERT_TRUE(rv);
+    EXPECT_TRUE(buffer->IsMapped());
+
+    // Get strides.
+    scoped_ptr<int[]> strides(new int[num_planes]);
+    buffer->GetStride(strides.get());
+
+    // Copy and compare mapped buffers.
+    for (size_t plane = 0; plane < num_planes; ++plane) {
+      size_t row_size_in_bytes;
+      EXPECT_TRUE(GpuMemoryBufferImpl::RowSizeInBytes(
+          buffer_size.width(), configuration.format, plane,
+          &row_sizes_in_bytes));
+
+      scoped_ptr<char[]> data(new char[row_size_in_bytes]);
+      memset(data.get(), 0x2a + plane, row_size_in_bytes);
+
+      size_t height =
+          buffer_size.height() /
+          GpuMemoryBufferImpl::SubsamplingFactor(configuration.format, plane);
+      for (size_t y = 0; y < height; ++y) {
+        memcpy(static_cast<char*>(mapped_buffers[plane]) + y * strides[plane],
+               data.get(), row_size_in_bytes);
+        EXPECT_EQ(memcmp(static_cast<char*>(mapped_buffers[plane]) +
+                             y * strides[plane],
+                         data.get(), row_size_in_bytes),
+                  0);
+      }
+    }
+
+    buffer->Unmap();
+    EXPECT_FALSE(buffer->IsMapped());
+
+    // Remap the buffer, and compare again. It should contain the same data.
+    rv = buffer->Map(mapped_buffers.get());
+    ASSERT_TRUE(rv);
+    EXPECT_TRUE(buffer->IsMapped());
+
+    buffer->GetStride(strides.get());
+
+    for (size_t plane = 0; plane < num_planes; ++plane) {
+      size_t row_size_in_bytes;
+      EXPECT_TRUE(GpuMemoryBufferImpl::RowSizeInBytes(
+          buffer_size.width(), configuration.format, plane,
+          &row_sizes_in_bytes));
+
+      scoped_ptr<char[]> data(new char[row_size_in_bytes]);
+      memset(data.get(), 0x2a + plane, row_size_in_bytes);
+
+      size_t height =
+          buffer_size.height() /
+          GpuMemoryBufferImpl::SubsamplingFactor(configuration.format, plane);
+      for (size_t y = 0; y < height; ++y) {
+        EXPECT_EQ(memcmp(static_cast<char*>(mapped_buffers[plane]) +
+                             y * strides[plane],
+                         data.get(), row_size_in_bytes),
+                  0);
+      }
+    }
+  }
+}
+
 std::vector<gfx::GpuMemoryBufferType> GetSupportedGpuMemoryBufferTypes() {
   std::vector<gfx::GpuMemoryBufferType> supported_types;
   GpuMemoryBufferFactory::GetSupportedTypes(&supported_types);