[PATCH 1/2] dma-fence: Propagate errors to dma-fence-array container

[Chris Wilson]

When one of the array of fences is signaled, propagate its errors to the
parent fence-array (keeping the first error to be raised).

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal at linaro.org>
Cc: Gustavo Padovan <gustavo at padovan.org>
---
 drivers/dma-buf/dma-fence-array.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c
index a8c254497251..f931226616c0 100644
--- a/drivers/dma-buf/dma-fence-array.c
+++ b/drivers/dma-buf/dma-fence-array.c
@@ -46,6 +46,9 @@ static void dma_fence_array_cb_func(struct dma_fence *f,
 		container_of(cb, struct dma_fence_array_cb, cb);
 	struct dma_fence_array *array = array_cb->array;
 
+	if (atomic_read(&array->num_pending) > 0)
+		cmpxchg_local(&array->base.error, 0, f->error);
+
 	if (atomic_dec_and_test(&array->num_pending))
 		irq_work_queue(&array->work);
 	else
@@ -71,6 +74,7 @@ static bool dma_fence_array_enable_signaling(struct dma_fence *fence)
 		dma_fence_get(&array->base);
 		if (dma_fence_add_callback(array->fences[i], &cb[i].cb,
 					   dma_fence_array_cb_func)) {
+			cmpxchg(&array->base.error, 0, array->fences[i]->error);
 			dma_fence_put(&array->base);
 			if (atomic_dec_and_test(&array->num_pending))
 				return false;
-- 
2.20.1