Makes it easier to extract the fences in a dma_fence_array.
Signed-off-by: Christian König christian.koenig@amd.com --- drivers/dma-buf/dma-fence-array.c | 42 +++++++++++++++++++++++++++++++ include/linux/dma-fence-array.h | 24 ++++++++++++++++++ 2 files changed, 66 insertions(+)
diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c index ea7713b40514..3bc2663a3f30 100644 --- a/drivers/dma-buf/dma-fence-array.c +++ b/drivers/dma-buf/dma-fence-array.c @@ -276,3 +276,45 @@ bool dma_fence_match_context(struct dma_fence *fence, u64 context) return true; } EXPORT_SYMBOL(dma_fence_match_context); + +/** + * dma_fence_array_first - return the first fence in an array + * @cursor: cursor for the current position + * @array: array with the fences + * + * Returns the first fence in the array or NULL if the array is empty. + * If the array parameter isn't a dma_fence_array return it unmodified. + */ +struct dma_fence *dma_fence_array_first(struct dma_fence_array_cursor *cursor, + struct dma_fence *array) +{ + cursor->array = to_dma_fence_array(array); + if (!cursor->array) + return array; + + if (!cursor->array->num_fences) + return NULL; + + cursor->index = 0; + return cursor->array->fences[cursor->index++]; + +} +EXPORT_SYMBOL(dma_fence_array_first); + +/** + * dma_fence_array_next - return the next fence in the array + * @cursor: cursor for the current position + * + * Returns the next fence from the array or NULL if we don't have any more + */ +struct dma_fence *dma_fence_array_next(struct dma_fence_array_cursor *cursor) +{ + if (!cursor->array) + return NULL; + + if (cursor->index >= cursor->array->num_fences) + return NULL; + + return cursor->array->fences[cursor->index++]; +} +EXPORT_SYMBOL(dma_fence_array_next); diff --git a/include/linux/dma-fence-array.h b/include/linux/dma-fence-array.h index 35d1d1e7c93b..2a71fd003dfa 100644 --- a/include/linux/dma-fence-array.h +++ b/include/linux/dma-fence-array.h @@ -124,4 +124,28 @@ dma_fence_array_create(int num_fences, struct dma_fence **fences, u64 context,
bool dma_fence_match_context(struct dma_fence *fence, u64 context);
+/** + * struct dma_fence_array_cursor - cursor for the fences in an array + */ +struct dma_fence_array_cursor { + struct dma_fence_array *array; + unsigned int index; +}; + +struct dma_fence *dma_fence_array_first(struct dma_fence_array_cursor *cursor, + struct dma_fence *array); +struct dma_fence *dma_fence_array_next(struct dma_fence_array_cursor *cursor); + +/** + * dma_fence_array_for_each - walk over all fences in a fence array + * @fence: the current fence + * @cursor: cursor for the walk + * @array: potentitally fence array + * + * Walk over all the fences in the array. + */ +#define dma_fence_array_for_each(fence, cursor, array) \ + for (fence = dma_fence_array_first(&(cursor), array); \ + fence; fence = dma_fence_array_next(&(cursor))) + #endif /* __LINUX_DMA_FENCE_ARRAY_H */