drm: handle compact dma scatter lists in drm_clflush_sg()

So far the assumption was that each scatter list entry contains a single
page. This might not hold in the future, when we'll introduce compact
scatter lists, so prepare for this here.

Reference: http://www.spinics.net/lists/dri-devel/msg33917.html
Signed-off-by: Imre Deak <imre.deak@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index a575cb2e6bdb..bc8edbeca3fd 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c
@@ -105,12 +105,11 @@ drm_clflush_sg(struct sg_table *st)
 {
 #if defined(CONFIG_X86)
         if (cpu_has_clflush) {
-                struct scatterlist *sg;
-                int i;
+                struct sg_page_iter sg_iter;
 
                 mb();
-                for_each_sg(st->sgl, sg, st->nents, i)
-                        drm_clflush_page(sg_page(sg));
+                for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
+                        drm_clflush_page(sg_iter.page);
                 mb();
 
                 return;