cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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dma-fence-unwrap.h (2714B)

      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/*
      3 * fence-chain: chain fences together in a timeline
      4 *
      5 * Copyright (C) 2022 Advanced Micro Devices, Inc.
      6 * Authors:
      7 *	Christian König <christian.koenig@amd.com>
      8 */
      9
     10#ifndef __LINUX_DMA_FENCE_UNWRAP_H
     11#define __LINUX_DMA_FENCE_UNWRAP_H
     12
     13#include <linux/dma-fence-chain.h>
     14#include <linux/dma-fence-array.h>
     15
     16/**
     17 * struct dma_fence_unwrap - cursor into the container structure
     18 *
     19 * Should be used with dma_fence_unwrap_for_each() iterator macro.
     20 */
     21struct dma_fence_unwrap {
     22	/**
     23	 * @chain: potential dma_fence_chain, but can be other fence as well
     24	 */
     25	struct dma_fence *chain;
     26	/**
     27	 * @array: potential dma_fence_array, but can be other fence as well
     28	 */
     29	struct dma_fence *array;
     30	/**
     31	 * @index: last returned index if @array is really a dma_fence_array
     32	 */
     33	unsigned int index;
     34};
     35
     36/* Internal helper to start new array iteration, don't use directly */
     37static inline struct dma_fence *
     38__dma_fence_unwrap_array(struct dma_fence_unwrap * cursor)
     39{
     40	cursor->array = dma_fence_chain_contained(cursor->chain);
     41	cursor->index = 0;
     42	return dma_fence_array_first(cursor->array);
     43}
     44
     45/**
     46 * dma_fence_unwrap_first - return the first fence from fence containers
     47 * @head: the entrypoint into the containers
     48 * @cursor: current position inside the containers
     49 *
     50 * Unwraps potential dma_fence_chain/dma_fence_array containers and return the
     51 * first fence.
     52 */
     53static inline struct dma_fence *
     54dma_fence_unwrap_first(struct dma_fence *head, struct dma_fence_unwrap *cursor)
     55{
     56	cursor->chain = dma_fence_get(head);
     57	return __dma_fence_unwrap_array(cursor);
     58}
     59
     60/**
     61 * dma_fence_unwrap_next - return the next fence from a fence containers
     62 * @cursor: current position inside the containers
     63 *
     64 * Continue unwrapping the dma_fence_chain/dma_fence_array containers and return
     65 * the next fence from them.
     66 */
     67static inline struct dma_fence *
     68dma_fence_unwrap_next(struct dma_fence_unwrap *cursor)
     69{
     70	struct dma_fence *tmp;
     71
     72	++cursor->index;
     73	tmp = dma_fence_array_next(cursor->array, cursor->index);
     74	if (tmp)
     75		return tmp;
     76
     77	cursor->chain = dma_fence_chain_walk(cursor->chain);
     78	return __dma_fence_unwrap_array(cursor);
     79}
     80
     81/**
     82 * dma_fence_unwrap_for_each - iterate over all fences in containers
     83 * @fence: current fence
     84 * @cursor: current position inside the containers
     85 * @head: starting point for the iterator
     86 *
     87 * Unwrap dma_fence_chain and dma_fence_array containers and deep dive into all
     88 * potential fences in them. If @head is just a normal fence only that one is
     89 * returned.
     90 */
     91#define dma_fence_unwrap_for_each(fence, cursor, head)			\
     92	for (fence = dma_fence_unwrap_first(head, cursor); fence;	\
     93	     fence = dma_fence_unwrap_next(cursor))
     94
     95#endif