virtio-gpu must make sure scatter list segments are not too big.
Gerd Hoffmann (2): drm: allow limiting the scatter list size. drm/virtio: set max_segment
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/virtio/virtgpu_kms.c | 1 + drivers/gpu/drm/xen/xen_drm_front_gem.c | 3 ++- 16 files changed, 44 insertions(+), 17 deletions(-)
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. v3: move max_segment next to the other gem fields.
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 f4f68e7a9149..c455ef404ca6 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -308,6 +308,14 @@ struct drm_device { /** @vma_offset_manager: GEM information */ struct drm_vma_offset_manager *vma_offset_manager;
+ /** + * @max_segment: + * + * Max size for scatter list segments for GEM objects. When + * unset the default (SCATTERLIST_MAX_SEGMENT) is used. + */ + size_t max_segment; + /** @vram_mm: VRAM MM memory manager */ struct drm_vram_mm *vram_mm;
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 39ff95b75357..7865d5026856 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 *
When initializing call virtio_max_dma_size() to figure the scatter list limit. Needed to make virtio-gpu work properly with SEV.
v2: place max_segment in drm driver not gem object.
Signed-off-by: Gerd Hoffmann kraxel@redhat.com --- drivers/gpu/drm/virtio/virtgpu_kms.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index 75d0dc2f6d28..151471acdfcf 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -167,6 +167,7 @@ int virtio_gpu_init(struct drm_device *dev) DRM_ERROR("failed to alloc vbufs\n"); goto err_vbufs; } + dev->max_segment = virtio_max_dma_size(vgdev->vdev);
/* get display info */ virtio_cread_le(vgdev->vdev, struct virtio_gpu_config,
On Mon, Sep 07, 2020 at 08:33:41AM +0200, Gerd Hoffmann wrote:
So this all feels a bit irky and mid-layer, and why can't the various helpers not just use dma_max_mapping_size(drm_device->dev) directly.
And then I read that dma api use in virtio subsystem is a huge mess of hacks, and that it doesn't set up these quirks through the dma api abstraction but throught it's own abstraction on top. So we don't really have any other option I think.
I think would be good to add a TODO item to the virtio_max_dma_size call like:
TODO: once virtio uses the dma api correctly, remove the explicit max_segment handling na duse dma_max_mapping_size directly everywhere.
Or maybe also put that into the @max_segment kerneldoc in the drm_device struct.
With that: Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch on the series. -Daniel
dri-devel@lists.freedesktop.org
-
Daniel Vetter -
Gerd Hoffmann