linux/drivers/dma-buf/dma-fence-unwrap.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * dma-fence-util: misc functions for dma_fence objects
 *
 * Copyright (C) 2022 Advanced Micro Devices, Inc.
 * Authors:
 *	Christian König <[email protected]>
 */

#include <linux/dma-fence.h>
#include <linux/dma-fence-array.h>
#include <linux/dma-fence-chain.h>
#include <linux/dma-fence-unwrap.h>
#include <linux/slab.h>

/* Internal helper to start new array iteration, don't use directly */
static struct dma_fence *
__dma_fence_unwrap_array(struct dma_fence_unwrap *cursor)
{ … }

/**
 * dma_fence_unwrap_first - return the first fence from fence containers
 * @head: the entrypoint into the containers
 * @cursor: current position inside the containers
 *
 * Unwraps potential dma_fence_chain/dma_fence_array containers and return the
 * first fence.
 */
struct dma_fence *dma_fence_unwrap_first(struct dma_fence *head,
					 struct dma_fence_unwrap *cursor)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * dma_fence_unwrap_next - return the next fence from a fence containers
 * @cursor: current position inside the containers
 *
 * Continue unwrapping the dma_fence_chain/dma_fence_array containers and return
 * the next fence from them.
 */
struct dma_fence *dma_fence_unwrap_next(struct dma_fence_unwrap *cursor)
{ … }
EXPORT_SYMBOL_GPL(…);

/* Implementation for the dma_fence_merge() marco, don't use directly */
struct dma_fence *__dma_fence_unwrap_merge(unsigned int num_fences,
					   struct dma_fence **fences,
					   struct dma_fence_unwrap *iter)
{ … }
EXPORT_SYMBOL_GPL(…);