Rather than (incompletely [0]) re-implementing drm_gem_mmap() and drm_gem_mmap_obj() helpers, call them directly from the rockchip mmap routines.
Once the core functions return successfully, the rockchip mmap routines can still use dma_mmap_attrs() to simply mmap the entire buffer.
[0] Previously, we were performing the mmap() without first taking a reference on the underlying gem buffer. This could leak ptes if the gem object is destroyed while userspace is still holding the mapping.
Signed-off-by: Daniel Kurtz djkurtz@chromium.org Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch Cc: stable@vger.kernel.org
--- drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 67 +++++++++++++++-------------- 1 file changed, 34 insertions(+), 33 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index eb2282c..eba5f8a 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -54,55 +54,56 @@ static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj) &rk_obj->dma_attrs); }
-int rockchip_gem_mmap_buf(struct drm_gem_object *obj, - struct vm_area_struct *vma) +static int rockchip_drm_gem_object_mmap(struct drm_gem_object *obj, + struct vm_area_struct *vma) + { + int ret; struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj); struct drm_device *drm = obj->dev; - unsigned long vm_size;
- vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; - vm_size = vma->vm_end - vma->vm_start; - - if (vm_size > obj->size) - return -EINVAL; + /* + * dma_alloc_attrs() allocated a struct page table for rk_obj, so clear + * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap(). + */ + vma->vm_flags &= ~VM_PFNMAP;
- return dma_mmap_attrs(drm->dev, vma, rk_obj->kvaddr, rk_obj->dma_addr, + ret = dma_mmap_attrs(drm->dev, vma, rk_obj->kvaddr, rk_obj->dma_addr, obj->size, &rk_obj->dma_attrs); + if (ret) + drm_gem_vm_close(vma); + + return ret; }
-/* drm driver mmap file operations */ -int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) +int rockchip_gem_mmap_buf(struct drm_gem_object *obj, + struct vm_area_struct *vma) { - struct drm_file *priv = filp->private_data; - struct drm_device *dev = priv->minor->dev; - struct drm_gem_object *obj; - struct drm_vma_offset_node *node; + struct drm_device *drm = obj->dev; int ret;
- if (drm_device_is_unplugged(dev)) - return -ENODEV; + mutex_lock(&drm->struct_mutex); + ret = drm_gem_mmap_obj(obj, obj->size, vma); + mutex_unlock(&drm->struct_mutex); + if (ret) + return ret;
- mutex_lock(&dev->struct_mutex); + return rockchip_drm_gem_object_mmap(obj, vma); +}
- node = drm_vma_offset_exact_lookup(dev->vma_offset_manager, - vma->vm_pgoff, - vma_pages(vma)); - if (!node) { - mutex_unlock(&dev->struct_mutex); - DRM_ERROR("failed to find vma node.\n"); - return -EINVAL; - } else if (!drm_vma_node_is_allowed(node, filp)) { - mutex_unlock(&dev->struct_mutex); - return -EACCES; - } +/* drm driver mmap file operations */ +int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct drm_gem_object *obj; + int ret;
- obj = container_of(node, struct drm_gem_object, vma_node); - ret = rockchip_gem_mmap_buf(obj, vma); + ret = drm_gem_mmap(filp, vma); + if (ret) + return ret;
- mutex_unlock(&dev->struct_mutex); + obj = vma->vm_private_data;
- return ret; + return rockchip_drm_gem_object_mmap(obj, vma); }
struct rockchip_gem_object *