lavu: add Vulkan hwcontext code

This commit adds the necessary code to initialize and use a Vulkan device
within the hwcontext libavutil framework.
Currently direct mapping to VAAPI and DRM frames is functional, and
transfers to CUDA and native frames are supported.

Lets hope the future Vulkan video decode extension fits well within this
framework.

1 files changed, 158 insertions, 0 deletions

diff --git a/libavutil/hwcontext_vulkan.h b/libavutil/hwcontext_vulkan.h
new file mode 100644
index 0000000000..01d6d98b01
--- /dev/null
+++ b/libavutil/hwcontext_vulkan.h
@@ -0,0 +1,158 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_HWCONTEXT_VULKAN_H
+#define AVUTIL_HWCONTEXT_VULKAN_H
+
+#include <vulkan/vulkan.h>
+
+/**
+ * @file
+ * API-specific header for AV_HWDEVICE_TYPE_VULKAN.
+ *
+ * For user-allocated pools, AVHWFramesContext.pool must return AVBufferRefs
+ * with the data pointer set to an AVVkFrame.
+ */
+
+/**
+ * Main Vulkan context, allocated as AVHWDeviceContext.hwctx.
+ * All of these can be set before init to change what the context uses
+ */
+typedef struct AVVulkanDeviceContext {
+    /**
+     * Custom memory allocator, else NULL
+     */
+    const VkAllocationCallbacks *alloc;
+    /**
+     * Instance
+     */
+    VkInstance inst;
+    /**
+     * Physical device
+     */
+    VkPhysicalDevice phys_dev;
+    /**
+     * Active device
+     */
+    VkDevice act_dev;
+    /**
+     * Queue family index for graphics
+     * @note av_hwdevice_create() will set all 3 queue indices if unset
+     * If there is no dedicated queue for compute or transfer operations,
+     * they will be set to the graphics queue index which can handle both.
+     */
+    int queue_family_index;
+    /**
+     * Queue family index for transfer ops only
+     */
+    int queue_family_tx_index;
+    /**
+     * Queue family index for compute ops
+     */
+    int queue_family_comp_index;
+} AVVulkanDeviceContext;
+
+/**
+ * Allocated as AVHWFramesContext.hwctx, used to set pool-specific options
+ */
+typedef struct AVVulkanFramesContext {
+    /**
+     * Controls the tiling of output frames.
+     */
+    VkImageTiling tiling;
+    /**
+     * Defines extra usage of output frames. This is bitwise OR'd with the
+     * standard usage flags (SAMPLED, STORAGE, TRANSFER_SRC and TRANSFER_DST).
+     */
+    VkImageUsageFlagBits usage;
+    /**
+     * Extension data for image creation. By default, if the extension is
+     * available, this will be chained to a VkImageFormatListCreateInfoKHR.
+     */
+    void *create_pnext;
+    /**
+     * Extension data for memory allocation. Must have as many entries as
+     * the number of planes of the sw_format.
+     * This will be chained to VkExportMemoryAllocateInfo, which is used
+     * to make all pool images exportable to other APIs.
+     */
+    void *alloc_pnext[AV_NUM_DATA_POINTERS];
+} AVVulkanFramesContext;
+
+/*
+ * Frame structure, the VkFormat of the image will always match
+ * the pool's sw_format.
+ * All frames, imported or allocated, will be created with the
+ * VK_IMAGE_CREATE_ALIAS_BIT flag set, so the memory may be aliased if needed.
+ *
+ * @note the size of this structure is not part of the ABI, to allocate
+ * you must use @av_vk_frame_alloc().
+ */
+typedef struct AVVkFrame {
+    /**
+     * Vulkan images to which the memory is bound to.
+     */
+    VkImage img[AV_NUM_DATA_POINTERS];
+
+    /**
+     * Same tiling must be used for all images.
+     */
+    VkImageTiling tiling;
+
+    /**
+     * Memory backing the images. Could be less than the amount of images
+     * if importing from a DRM or VAAPI frame.
+     */
+    VkDeviceMemory mem[AV_NUM_DATA_POINTERS];
+    size_t size[AV_NUM_DATA_POINTERS];
+
+    /**
+     * OR'd flags for all memory allocated
+     */
+    VkMemoryPropertyFlagBits flags;
+
+    /**
+     * Updated after every barrier
+     */
+    VkAccessFlagBits access[AV_NUM_DATA_POINTERS];
+    VkImageLayout layout[AV_NUM_DATA_POINTERS];
+
+    /**
+     * Per-image semaphores. Must not be freed manually. Must be waited on
+     * and signalled at every queue submission.
+     */
+    VkSemaphore sem[AV_NUM_DATA_POINTERS];
+
+    /**
+     * Internal data.
+     */
+    struct AVVkFrameInternal *internal;
+} AVVkFrame;
+
+/**
+ * Allocates a single AVVkFrame and initializes everything as 0.
+ * @note Must be freed via av_free()
+ */
+AVVkFrame *av_vk_frame_alloc(void);
+
+/**
+ * Returns the format of each image up to the number of planes for a given sw_format.
+ */
+const VkFormat *av_vkfmt_from_pixfmt(enum AVPixelFormat p);
+
+#endif /* AVUTIL_HWCONTEXT_VULKAN_H */