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Diffstat (limited to 'include/linux/dma-fence-chain.h')
| -rw-r--r-- | include/linux/dma-fence-chain.h | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/include/linux/dma-fence-chain.h b/include/linux/dma-fence-chain.h new file mode 100644 index 000000000000..934a442db8ac --- /dev/null +++ b/include/linux/dma-fence-chain.h @@ -0,0 +1,81 @@ +/* + * fence-chain: chain fences together in a timeline + * + * Copyright (C) 2018 Advanced Micro Devices, Inc. + * Authors: + * Christian König <christian.koenig@amd.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program 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 General Public License for + * more details. + */ + +#ifndef __LINUX_DMA_FENCE_CHAIN_H +#define __LINUX_DMA_FENCE_CHAIN_H + +#include <linux/dma-fence.h> +#include <linux/irq_work.h> + +/** + * struct dma_fence_chain - fence to represent an node of a fence chain + * @base: fence base class + * @lock: spinlock for fence handling + * @prev: previous fence of the chain + * @prev_seqno: original previous seqno before garbage collection + * @fence: encapsulated fence + * @cb: callback structure for signaling + * @work: irq work item for signaling + */ +struct dma_fence_chain { + struct dma_fence base; + spinlock_t lock; + struct dma_fence __rcu *prev; + u64 prev_seqno; + struct dma_fence *fence; + struct dma_fence_cb cb; + struct irq_work work; +}; + +extern const struct dma_fence_ops dma_fence_chain_ops; + +/** + * to_dma_fence_chain - cast a fence to a dma_fence_chain + * @fence: fence to cast to a dma_fence_array + * + * Returns NULL if the fence is not a dma_fence_chain, + * or the dma_fence_chain otherwise. + */ +static inline struct dma_fence_chain * +to_dma_fence_chain(struct dma_fence *fence) +{ + if (!fence || fence->ops != &dma_fence_chain_ops) + return NULL; + + return container_of(fence, struct dma_fence_chain, base); +} + +/** + * dma_fence_chain_for_each - iterate over all fences in chain + * @iter: current fence + * @head: starting point + * + * Iterate over all fences in the chain. We keep a reference to the current + * fence while inside the loop which must be dropped when breaking out. + */ +#define dma_fence_chain_for_each(iter, head) \ + for (iter = dma_fence_get(head); iter; \ + iter = dma_fence_chain_walk(iter)) + +struct dma_fence *dma_fence_chain_walk(struct dma_fence *fence); +int dma_fence_chain_find_seqno(struct dma_fence **pfence, uint64_t seqno); +void dma_fence_chain_init(struct dma_fence_chain *chain, + struct dma_fence *prev, + struct dma_fence *fence, + uint64_t seqno); + +#endif /* __LINUX_DMA_FENCE_CHAIN_H */ |