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.c b/drivers/gpu/drm/i915/i915_gem.c
index 30117dc..5cf6140 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -411,8 +411,7 @@
int obj_do_bit17_swizzling, page_do_bit17_swizzling;
int prefaulted = 0;
int needs_clflush = 0;
- struct scatterlist *sg;
- int i;
+ struct sg_page_iter sg_iter;
user_data = to_user_ptr(args->data_ptr);
remain = args->size;
@@ -441,11 +440,9 @@
offset = args->offset;
- for_each_sg(obj->pages->sgl, sg, obj->pages->nents, i) {
- struct page *page;
-
- if (i < offset >> PAGE_SHIFT)
- continue;
+ for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
+ offset >> PAGE_SHIFT) {
+ struct page *page = sg_iter.page;
if (remain <= 0)
break;
@@ -460,7 +457,6 @@
if ((shmem_page_offset + page_length) > PAGE_SIZE)
page_length = PAGE_SIZE - shmem_page_offset;
- page = sg_page(sg);
page_do_bit17_swizzling = obj_do_bit17_swizzling &&
(page_to_phys(page) & (1 << 17)) != 0;
@@ -732,8 +728,7 @@
int hit_slowpath = 0;
int needs_clflush_after = 0;
int needs_clflush_before = 0;
- int i;
- struct scatterlist *sg;
+ struct sg_page_iter sg_iter;
user_data = to_user_ptr(args->data_ptr);
remain = args->size;
@@ -768,13 +763,11 @@
offset = args->offset;
obj->dirty = 1;
- for_each_sg(obj->pages->sgl, sg, obj->pages->nents, i) {
- struct page *page;
+ for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents,
+ offset >> PAGE_SHIFT) {
+ struct page *page = sg_iter.page;
int partial_cacheline_write;
- if (i < offset >> PAGE_SHIFT)
- continue;
-
if (remain <= 0)
break;
@@ -796,7 +789,6 @@
((shmem_page_offset | page_length)
& (boot_cpu_data.x86_clflush_size - 1));
- page = sg_page(sg);
page_do_bit17_swizzling = obj_do_bit17_swizzling &&
(page_to_phys(page) & (1 << 17)) != 0;