linux-stable/include/linux/dma-fence-array.h
Christian König 64a8f92fd7 dma-buf: add dma_fence_unwrap v2
Add a general purpose helper to deep dive into dma_fence_chain/dma_fence_array
structures and iterate over all the fences in them.

This is useful when we need to flatten out all fences in those structures.

v2: some selftests cleanup, improved function naming and documentation

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220311110244.1245-1-christian.koenig@amd.com
2022-03-25 14:18:28 +01:00

90 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* fence-array: aggregates fence to be waited together
*
* Copyright (C) 2016 Collabora Ltd
* Copyright (C) 2016 Advanced Micro Devices, Inc.
* Authors:
* Gustavo Padovan <gustavo@padovan.org>
* Christian König <christian.koenig@amd.com>
*/
#ifndef __LINUX_DMA_FENCE_ARRAY_H
#define __LINUX_DMA_FENCE_ARRAY_H
#include <linux/dma-fence.h>
#include <linux/irq_work.h>
/**
* struct dma_fence_array_cb - callback helper for fence array
* @cb: fence callback structure for signaling
* @array: reference to the parent fence array object
*/
struct dma_fence_array_cb {
struct dma_fence_cb cb;
struct dma_fence_array *array;
};
/**
* struct dma_fence_array - fence to represent an array of fences
* @base: fence base class
* @lock: spinlock for fence handling
* @num_fences: number of fences in the array
* @num_pending: fences in the array still pending
* @fences: array of the fences
* @work: internal irq_work function
*/
struct dma_fence_array {
struct dma_fence base;
spinlock_t lock;
unsigned num_fences;
atomic_t num_pending;
struct dma_fence **fences;
struct irq_work work;
};
/**
* to_dma_fence_array - cast a fence to a dma_fence_array
* @fence: fence to cast to a dma_fence_array
*
* Returns NULL if the fence is not a dma_fence_array,
* or the dma_fence_array otherwise.
*/
static inline struct dma_fence_array *
to_dma_fence_array(struct dma_fence *fence)
{
if (!fence || !dma_fence_is_array(fence))
return NULL;
return container_of(fence, struct dma_fence_array, base);
}
/**
* dma_fence_array_for_each - iterate over all fences in array
* @fence: current fence
* @index: index into the array
* @head: potential dma_fence_array object
*
* Test if @array is a dma_fence_array object and if yes iterate over all fences
* in the array. If not just iterate over the fence in @array itself.
*
* For a deep dive iterator see dma_fence_unwrap_for_each().
*/
#define dma_fence_array_for_each(fence, index, head) \
for (index = 0, fence = dma_fence_array_first(head); fence; \
++(index), fence = dma_fence_array_next(head, index))
struct dma_fence_array *dma_fence_array_create(int num_fences,
struct dma_fence **fences,
u64 context, unsigned seqno,
bool signal_on_any);
bool dma_fence_match_context(struct dma_fence *fence, u64 context);
struct dma_fence *dma_fence_array_first(struct dma_fence *head);
struct dma_fence *dma_fence_array_next(struct dma_fence *head,
unsigned int index);
#endif /* __LINUX_DMA_FENCE_ARRAY_H */