Add fence support for TransferBuffers

src/gpu/vk/GrVkGpu.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrVkGpu.h"
 
 #include "GrContextOptions.h"
@@ skipping 1870 matching lines @@
     // Currently it is fine for us to always pass in 1 for the clear count even if no attachment
     // uses it. In the current state, we also only use the LOAD_OP_CLEAR for the color attachment
     // which is always at the first attachment.
     fCurrentCmdBuffer->beginRenderPass(this, renderPass, 1, colorClear, *target, *pBounds, true);
     fCurrentCmdBuffer->executeCommands(this, buffer);
     fCurrentCmdBuffer->endRenderPass(this);
 
     this->didWriteToSurface(target, &bounds);
 }
 
+GrFence SK_WARN_UNUSED_RESULT GrVkGpu::insertFence() const {
+    VkFenceCreateInfo createInfo;
+    memset(&createInfo, 0, sizeof(VkFenceCreateInfo));
+    createInfo.sType = VK_STRUCTURE_TYPE_FENCE_CREATE_INFO;
+    createInfo.pNext = nullptr;
+    createInfo.flags = 0;
+    VkFence fence = VK_NULL_HANDLE;
+    VkResult result = GR_VK_CALL(this->vkInterface(), CreateFence(this->device(), &createInfo,
+                                                                  nullptr, &fence));
+    // TODO: verify that all QueueSubmits before this will finish before this fence signals
+    if (VK_SUCCESS == result) {
+        GR_VK_CALL(this->vkInterface(), QueueSubmit(this->queue(), 0, nullptr, fence));
+    }
+    return (GrFence)fence;
+}
+
+bool GrVkGpu::waitFence(GrFence fence, uint64_t timeout) const {
+    VkResult result = GR_VK_CALL(this->vkInterface(), WaitForFences(this->device(), 1,
+                                                                    (VkFence*)&fence,
+                                                                    VK_TRUE,
+                                                                    timeout));
+    return (VK_SUCCESS == result);
+}
+
+void GrVkGpu::deleteFence(GrFence fence) const {
+    GR_VK_CALL(this->vkInterface(), DestroyFence(this->device(), (VkFence)fence, nullptr));
+}
+