diff options
Diffstat (limited to 'include/linux/dma-fence-chain.h')
| -rw-r--r-- | include/linux/dma-fence-chain.h | 52 |
1 files changed, 46 insertions, 6 deletions
diff --git a/include/linux/dma-fence-chain.h b/include/linux/dma-fence-chain.h index 10462a029da2..54fe3443fd2c 100644 --- a/include/linux/dma-fence-chain.h +++ b/include/linux/dma-fence-chain.h @@ -12,25 +12,41 @@ #include <linux/dma-fence.h> #include <linux/irq_work.h> +#include <linux/slab.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 + * @lock: spinlock for fence handling */ 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; + union { + /** + * @cb: callback for signaling + * + * This is used to add the callback for signaling the + * complection of the fence chain. Never used at the same time + * as the irq work. + */ + struct dma_fence_cb cb; + + /** + * @work: irq work item for signaling + * + * Irq work structure to allow us to add the callback without + * running into lock inversion. Never used at the same time as + * the callback. + */ + struct irq_work work; + }; + spinlock_t lock; }; extern const struct dma_fence_ops dma_fence_chain_ops; @@ -52,6 +68,30 @@ to_dma_fence_chain(struct dma_fence *fence) } /** + * dma_fence_chain_alloc + * + * Returns a new struct dma_fence_chain object or NULL on failure. + */ +static inline struct dma_fence_chain *dma_fence_chain_alloc(void) +{ + return kmalloc(sizeof(struct dma_fence_chain), GFP_KERNEL); +}; + +/** + * dma_fence_chain_free + * @chain: chain node to free + * + * Frees up an allocated but not used struct dma_fence_chain object. This + * doesn't need an RCU grace period since the fence was never initialized nor + * published. After dma_fence_chain_init() has been called the fence must be + * released by calling dma_fence_put(), and not through this function. + */ +static inline void dma_fence_chain_free(struct dma_fence_chain *chain) +{ + kfree(chain); +}; + +/** * dma_fence_chain_for_each - iterate over all fences in chain * @iter: current fence * @head: starting point |