drm/i915: handle walking compact dma scatter lists
So far the assumption was that each dma scatter list entry contains only
a single page. This might not hold in the future, when we'll introduce
compact scatter lists, so prepare for this everywhere in the i915 code
where we walk such a list.
We'll fix the place _creating_ these lists separately in the next patch
to help the reviewing/bisectability.
Reference: http://www.spinics.net/lists/dri-devel/msg33917.html
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index abcba2f..f799708 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -473,28 +473,29 @@
void
i915_gem_object_do_bit_17_swizzle(struct drm_i915_gem_object *obj)
{
- struct scatterlist *sg;
- int page_count = obj->base.size >> PAGE_SHIFT;
+ struct sg_page_iter sg_iter;
int i;
if (obj->bit_17 == NULL)
return;
- for_each_sg(obj->pages->sgl, sg, page_count, i) {
- struct page *page = sg_page(sg);
+ i = 0;
+ for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
+ struct page *page = sg_iter.page;
char new_bit_17 = page_to_phys(page) >> 17;
if ((new_bit_17 & 0x1) !=
(test_bit(i, obj->bit_17) != 0)) {
i915_gem_swizzle_page(page);
set_page_dirty(page);
}
+ i++;
}
}
void
i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
{
- struct scatterlist *sg;
+ struct sg_page_iter sg_iter;
int page_count = obj->base.size >> PAGE_SHIFT;
int i;
@@ -508,11 +509,12 @@
}
}
- for_each_sg(obj->pages->sgl, sg, page_count, i) {
- struct page *page = sg_page(sg);
- if (page_to_phys(page) & (1 << 17))
+ i = 0;
+ for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
+ if (page_to_phys(sg_iter.page) & (1 << 17))
__set_bit(i, obj->bit_17);
else
__clear_bit(i, obj->bit_17);
+ i++;
}
}