[PATCH v4 1/3] drm/prime: use dma length macro when mapping sg

From: Shane Francis
Date: Wed Mar 25 2020 - 05:08:43 EST


As dma_map_sg can reorganize scatter-gather lists in a
way that can cause some later segments to be empty we should
always use the sg_dma_len macro to fetch the actual length.

This could now be 0 and not need to be mapped to a page or
address array

Signed-off-by: Shane Francis <bigbeeshane@xxxxxxxxx>
---
drivers/gpu/drm/drm_prime.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 86d9b0e45c8c..1de2cde2277c 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -967,7 +967,7 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,

index = 0;
for_each_sg(sgt->sgl, sg, sgt->nents, count) {
- len = sg->length;
+ len = sg_dma_len(sg);
page = sg_page(sg);
addr = sg_dma_address(sg);

--
2.26.0