Am 18.08.20 um 09:48 schrieb Gerd Hoffmann:
Add max_segment argument to drm_prime_pages_to_sg(). When set pass it
through to the __sg_alloc_table_from_pages() call, otherwise use
SCATTERLIST_MAX_SEGMENT.
Also add max_segment field to gem objects and pass it to
drm_prime_pages_to_sg() calls in drivers and helpers.
Signed-off-by: Gerd Hoffmann
I'm missing an explanation why this should be useful (it certainly is).
And the maximum segment size seems misplaced in the GEM object. This is
usually a property of the device or even completely constant.
Christian.
---
include/drm/drm_gem.h | 8
include/drm/drm_prime.h | 3 ++-
drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 3 ++-
drivers/gpu/drm/drm_gem_shmem_helper.c | 3 ++-
drivers/gpu/drm/drm_prime.c | 10 +++---
drivers/gpu/drm/etnaviv/etnaviv_gem.c | 3 ++-
drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 3 ++-
drivers/gpu/drm/msm/msm_gem.c | 3 ++-
drivers/gpu/drm/msm/msm_gem_prime.c | 3 ++-
drivers/gpu/drm/nouveau/nouveau_prime.c | 3 ++-
drivers/gpu/drm/radeon/radeon_prime.c | 3 ++-
drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 6 --
drivers/gpu/drm/tegra/gem.c | 3 ++-
drivers/gpu/drm/vgem/vgem_drv.c | 3 ++-
drivers/gpu/drm/xen/xen_drm_front_gem.c | 3 ++-
15 files changed, 43 insertions(+), 17 deletions(-)
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index 337a48321705..dea5e92e745b 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -241,6 +241,14 @@ struct drm_gem_object {
*/
size_t size;
+ /**
+* @max_segment:
+*
+* Max size for scatter list segments. When unset the default
+* (SCATTERLIST_MAX_SEGMENT) is used.
+*/
+ size_t max_segment;
+
/**
* @name:
*
diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h
index 9af7422b44cf..2c3689435cb4 100644
--- a/include/drm/drm_prime.h
+++ b/include/drm/drm_prime.h
@@ -88,7 +88,8 @@ void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void
*vaddr);
int drm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct
*vma);
int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma);
-struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int nr_pages);
+struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int
nr_pages,
+ size_t max_segment);
struct dma_buf *drm_gem_prime_export(struct drm_gem_object *obj,
int flags);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index 519ce4427fce..5e8a9760b33f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -303,7 +303,8 @@ static struct sg_table *amdgpu_dma_buf_map(struct
dma_buf_attachment *attach,
switch (bo->tbo.mem.mem_type) {
case TTM_PL_TT:
sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages,
- bo->tbo.num_pages);
+ bo->tbo.num_pages,
+ obj->max_segment);
if (IS_ERR(sgt))
return sgt;
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
index 4b7cfbac4daa..cfb979d808fd 100644
--- a/drivers/gpu/drm/drm_gem_shmem_helper.c
+++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
@@ -656,7 +656,8 @@ struct sg_table *drm_gem_shmem_get_sg_table(struct
drm_gem_object *obj)
WARN_ON(shmem->base.import_attach);
- return drm_prime_pages_to_sg(shmem->pages, obj->size >> PAGE_SHIFT);
+ return drm_prime_pages_to_sg(shmem->pages, obj->size >> PAGE_SHIFT,
+obj->max_segment);
}
EXPORT_SYMBOL_GPL(drm_gem_shmem_get_sg_table);
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 1693aa7c14b5..27c783fd6633 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -802,7 +802,8 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =
{
*
* This is useful for implementing &drm_gem_object_funcs.get_sg_table.
*/
-struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int
nr_pages)
+struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int
nr_pages,
+ size_t max_segment)
{
struct sg_table *sg = NULL;
int ret;
@@ -813,8 +814,11 @@ struct sg_table *drm_prime_pages_to_sg(struct page
**pages, unsigned int nr_page
goto out;
}
- ret = sg_alloc_table_from_pages(sg, pages, nr_pages, 0,
- nr_pages << PAGE_SHIFT, GFP_KERNEL);
+ if (max_segment
