[PATCH v2 1/2] drm: allow limiting the scatter list size.

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 drm driver and pass it to drm_prime_pages_to_sg() calls in drivers and helpers.

v2: place max_segment in drm driver not gem object.

Signed-off-by: Gerd Hoffmann kraxel@redhat.com --- include/drm/drm_device.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_device.h b/include/drm/drm_device.h index 0988351d743c..47cb547a8115 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -329,6 +329,14 @@ struct drm_device { */ struct drm_fb_helper *fb_helper;

+ /** + * @max_segment: + * + * Max size for scatter list segments. When unset the default + * (SCATTERLIST_MAX_SEGMENT) is used. + */ + size_t max_segment; + /* Everything below here is for legacy driver, never use! */ /* private: */ #if IS_ENABLED(CONFIG_DRM_LEGACY) 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..8f6a647757e7 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->dev->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..8f47b41b0b2f 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->dev->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 == 0 || max_segment > SCATTERLIST_MAX_SEGMENT) + max_segment = SCATTERLIST_MAX_SEGMENT; + ret = __sg_alloc_table_from_pages(sg, pages, nr_pages, 0, + nr_pages << PAGE_SHIFT, + max_segment, GFP_KERNEL); if (ret) goto out;

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c index f06e19e7be04..90654246b335 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c @@ -103,7 +103,8 @@ struct page **etnaviv_gem_get_pages(struct etnaviv_gem_object *etnaviv_obj) int npages = etnaviv_obj->base.size >> PAGE_SHIFT; struct sg_table *sgt;

- sgt = drm_prime_pages_to_sg(etnaviv_obj->pages, npages); + sgt = drm_prime_pages_to_sg(etnaviv_obj->pages, npages, + etnaviv_obj->base.dev->max_segment); if (IS_ERR(sgt)) { dev_err(dev->dev, "failed to allocate sgt: %ld\n", PTR_ERR(sgt)); diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c index 6d9e5c3c4dd5..f65be0fffb3d 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c @@ -19,7 +19,8 @@ struct sg_table *etnaviv_gem_prime_get_sg_table(struct drm_gem_object *obj) if (WARN_ON(!etnaviv_obj->pages)) /* should have already pinned! */ return ERR_PTR(-EINVAL);

- return drm_prime_pages_to_sg(etnaviv_obj->pages, npages); + return drm_prime_pages_to_sg(etnaviv_obj->pages, npages, + obj->dev->max_segment); }

void *etnaviv_gem_prime_vmap(struct drm_gem_object *obj) diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index b2f49152b4d4..dbf1437c3dac 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -126,7 +126,8 @@ static struct page **get_pages(struct drm_gem_object *obj)

msm_obj->pages = p;

- msm_obj->sgt = drm_prime_pages_to_sg(p, npages); + msm_obj->sgt = drm_prime_pages_to_sg(p, npages, + obj->dev->max_segment); if (IS_ERR(msm_obj->sgt)) { void *ptr = ERR_CAST(msm_obj->sgt);

diff --git a/drivers/gpu/drm/msm/msm_gem_prime.c b/drivers/gpu/drm/msm/msm_gem_prime.c index d7c8948427fe..6337cd1f9428 100644 --- a/drivers/gpu/drm/msm/msm_gem_prime.c +++ b/drivers/gpu/drm/msm/msm_gem_prime.c @@ -19,7 +19,8 @@ struct sg_table *msm_gem_prime_get_sg_table(struct drm_gem_object *obj) if (WARN_ON(!msm_obj->pages)) /* should have already pinned! */ return NULL;

- return drm_prime_pages_to_sg(msm_obj->pages, npages); + return drm_prime_pages_to_sg(msm_obj->pages, npages, + obj->dev->max_segment); }

void *msm_gem_prime_vmap(struct drm_gem_object *obj) diff --git a/drivers/gpu/drm/nouveau/nouveau_prime.c b/drivers/gpu/drm/nouveau/nouveau_prime.c index bae6a3eccee0..dd0ff032ae16 100644 --- a/drivers/gpu/drm/nouveau/nouveau_prime.c +++ b/drivers/gpu/drm/nouveau/nouveau_prime.c @@ -32,7 +32,8 @@ struct sg_table *nouveau_gem_prime_get_sg_table(struct drm_gem_object *obj) struct nouveau_bo *nvbo = nouveau_gem_object(obj); int npages = nvbo->bo.num_pages;

- return drm_prime_pages_to_sg(nvbo->bo.ttm->pages, npages); + return drm_prime_pages_to_sg(nvbo->bo.ttm->pages, npages, + obj->dev->max_segment); }

void *nouveau_gem_prime_vmap(struct drm_gem_object *obj) diff --git a/drivers/gpu/drm/radeon/radeon_prime.c b/drivers/gpu/drm/radeon/radeon_prime.c index b906e8fbd5f3..61a3fe147489 100644 --- a/drivers/gpu/drm/radeon/radeon_prime.c +++ b/drivers/gpu/drm/radeon/radeon_prime.c @@ -36,7 +36,8 @@ struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj) struct radeon_bo *bo = gem_to_radeon_bo(obj); int npages = bo->tbo.num_pages;

- return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages); + return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages, + obj->dev->max_segment); }

void *radeon_gem_prime_vmap(struct drm_gem_object *obj) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index b9275ba7c5a5..5ddb2d31a607 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -85,7 +85,8 @@ static int rockchip_gem_get_pages(struct rockchip_gem_object *rk_obj)

rk_obj->num_pages = rk_obj->base.size >> PAGE_SHIFT;

- rk_obj->sgt = drm_prime_pages_to_sg(rk_obj->pages, rk_obj->num_pages); + rk_obj->sgt = drm_prime_pages_to_sg(rk_obj->pages, rk_obj->num_pages, + rk_obj->base.dev->max_segment); if (IS_ERR(rk_obj->sgt)) { ret = PTR_ERR(rk_obj->sgt); goto err_put_pages; @@ -442,7 +443,8 @@ struct sg_table *rockchip_gem_prime_get_sg_table(struct drm_gem_object *obj) int ret;

if (rk_obj->pages) - return drm_prime_pages_to_sg(rk_obj->pages, rk_obj->num_pages); + return drm_prime_pages_to_sg(rk_obj->pages, rk_obj->num_pages, + obj->dev->max_segment);

sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index 723df142a981..a0abde747e95 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -284,7 +284,8 @@ static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)

bo->num_pages = bo->gem.size >> PAGE_SHIFT;

- bo->sgt = drm_prime_pages_to_sg(bo->pages, bo->num_pages); + bo->sgt = drm_prime_pages_to_sg(bo->pages, bo->num_pages, + bo->gem.dev->max_segment); if (IS_ERR(bo->sgt)) { err = PTR_ERR(bo->sgt); goto put_pages; diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index 313339bbff90..045461dc6319 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -321,7 +321,8 @@ static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj) { struct drm_vgem_gem_object *bo = to_vgem_bo(obj);

- return drm_prime_pages_to_sg(bo->pages, bo->base.size >> PAGE_SHIFT); + return drm_prime_pages_to_sg(bo->pages, bo->base.size >> PAGE_SHIFT, + obj->dev->max_segment); }

static struct drm_gem_object* vgem_prime_import(struct drm_device *dev, diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index f0b85e094111..61a8c1a9fb04 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -179,7 +179,8 @@ struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj) if (!xen_obj->pages) return ERR_PTR(-ENOMEM);

- return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages); + return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages, + gem_obj->dev->max_segment); }

struct drm_gem_object *