From: Christian König <ckoenig.leichtzumerken@xxxxxxxxx>
Add a helper to iterate over all fences in a dma_fence_array object.
v2 (Jason Ekstrand)
- Return NULL from dma_fence_array_first if head == NULL. This matches
the iterator behavior of dma_fence_chain_for_each in that it iterates
zero times if head == NULL.
- Return NULL from dma_fence_array_next if index > array->num_fences.
Signed-off-by: Jason Ekstrand <jason@xxxxxxxxxxxxxx>
---
drivers/dma-buf/dma-fence-array.c | 27 +++++++++++++++++++++++++++
include/linux/dma-fence-array.h | 17 +++++++++++++++++
2 files changed, 44 insertions(+)
diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c
index d3fbd950be94..2ac1afc697d0 100644
--- a/drivers/dma-buf/dma-fence-array.c
+++ b/drivers/dma-buf/dma-fence-array.c
@@ -201,3 +201,30 @@ bool dma_fence_match_context(struct dma_fence *fence, u64 context)
return true;
}
EXPORT_SYMBOL(dma_fence_match_context);
+
+struct dma_fence *dma_fence_array_first(struct dma_fence *head)
+{
+ struct dma_fence_array *array;
+
+ if (!head)
+ return NULL;
+
+ array = to_dma_fence_array(head);
+ if (!array)
+ return head;
+
+ return array->fences[0];
+}
+EXPORT_SYMBOL(dma_fence_array_first);
+
+struct dma_fence *dma_fence_array_next(struct dma_fence *head,
+ unsigned int index)
+{
+ struct dma_fence_array *array = to_dma_fence_array(head);
+
+ if (!array || index >= array->num_fences)
+ return NULL;
+
+ return array->fences[index];
+}
+EXPORT_SYMBOL(dma_fence_array_next);
diff --git a/include/linux/dma-fence-array.h b/include/linux/dma-fence-array.h
index 303dd712220f..588ac8089dd6 100644
--- a/include/linux/dma-fence-array.h
+++ b/include/linux/dma-fence-array.h
@@ -74,6 +74,19 @@ to_dma_fence_array(struct dma_fence *fence)
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.
+ */
+#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,
@@ -81,4 +94,8 @@ struct dma_fence_array *dma_fence_array_create(int num_fences,
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 */
--
2.24.1
