OpenCloudOS-Kernel/include/linux/dma-fence-unwrap.h

96 lines
2.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* fence-chain: chain fences together in a timeline
*
* Copyright (C) 2022 Advanced Micro Devices, Inc.
* Authors:
* Christian König <christian.koenig@amd.com>
*/
#ifndef __LINUX_DMA_FENCE_UNWRAP_H
#define __LINUX_DMA_FENCE_UNWRAP_H
#include <linux/dma-fence-chain.h>
#include <linux/dma-fence-array.h>
/**
* struct dma_fence_unwrap - cursor into the container structure
*
* Should be used with dma_fence_unwrap_for_each() iterator macro.
*/
struct dma_fence_unwrap {
/**
* @chain: potential dma_fence_chain, but can be other fence as well
*/
struct dma_fence *chain;
/**
* @array: potential dma_fence_array, but can be other fence as well
*/
struct dma_fence *array;
/**
* @index: last returned index if @array is really a dma_fence_array
*/
unsigned int index;
};
/* Internal helper to start new array iteration, don't use directly */
static inline struct dma_fence *
__dma_fence_unwrap_array(struct dma_fence_unwrap * cursor)
{
cursor->array = dma_fence_chain_contained(cursor->chain);
cursor->index = 0;
return dma_fence_array_first(cursor->array);
}
/**
* 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.
*/
static inline struct dma_fence *
dma_fence_unwrap_first(struct dma_fence *head, struct dma_fence_unwrap *cursor)
{
cursor->chain = dma_fence_get(head);
return __dma_fence_unwrap_array(cursor);
}
/**
* 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.
*/
static inline struct dma_fence *
dma_fence_unwrap_next(struct dma_fence_unwrap *cursor)
{
struct dma_fence *tmp;
++cursor->index;
tmp = dma_fence_array_next(cursor->array, cursor->index);
if (tmp)
return tmp;
cursor->chain = dma_fence_chain_walk(cursor->chain);
return __dma_fence_unwrap_array(cursor);
}
/**
* dma_fence_unwrap_for_each - iterate over all fences in containers
* @fence: current fence
* @cursor: current position inside the containers
* @head: starting point for the iterator
*
* Unwrap dma_fence_chain and dma_fence_array containers and deep dive into all
* potential fences in them. If @head is just a normal fence only that one is
* returned.
*/
#define dma_fence_unwrap_for_each(fence, cursor, head) \
for (fence = dma_fence_unwrap_first(head, cursor); fence; \
fence = dma_fence_unwrap_next(cursor))
#endif