Currently, virtio uses its own dumb_map_offset implementation,
virtio_gpu_mode_dumb_mmap. It works similarly to generic implementation,
drm_gem_dumb_map_offset, and using the generic implementation is
preferable (and making drivers to do so is a task stated on the DRM
subsystem's TODO list).

Thus, make driver use the generic implementation. This includes
VIRTGPU_MAP ioctl so it cannot be used to circumvent rules imposed by
drm_gem_dumb_map_offset (imported objects cannot be mapped).

Signed-off-by: Peter Shkenev <mustela@erminea.space>
---
Changes in v2:
  - Remove excessive include of drm_gem.h from virtgpu_ioctl.h
  - Remove obsoleted virtio_gpu_mode_dumb_mmap prototype from
    virtgpu_drv.h

 drivers/gpu/drm/virtio/virtgpu_drv.c   |  1 -
 drivers/gpu/drm/virtio/virtgpu_drv.h   |  3 ---
 drivers/gpu/drm/virtio/virtgpu_gem.c   | 15 ---------------
 drivers/gpu/drm/virtio/virtgpu_ioctl.c |  2 +-
 4 files changed, 1 insertion(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c
index ffca6e2e1c9a..909808398d66 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.c
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -184,7 +184,6 @@ static const struct drm_driver driver = {
 	.postclose = virtio_gpu_driver_postclose,
 
 	.dumb_create = virtio_gpu_mode_dumb_create,
-	.dumb_map_offset = virtio_gpu_mode_dumb_mmap,
 
 	DRM_FBDEV_SHMEM_DRIVER_OPS,
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 64c236169db8..76f6f29f819a 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -301,9 +301,6 @@ void virtio_gpu_gem_object_close(struct drm_gem_object *obj,
 int virtio_gpu_mode_dumb_create(struct drm_file *file_priv,
 				struct drm_device *dev,
 				struct drm_mode_create_dumb *args);
-int virtio_gpu_mode_dumb_mmap(struct drm_file *file_priv,
-			      struct drm_device *dev,
-			      uint32_t handle, uint64_t *offset_p);
 
 struct virtio_gpu_object_array *virtio_gpu_array_alloc(u32 nents);
 struct virtio_gpu_object_array*
diff --git a/drivers/gpu/drm/virtio/virtgpu_gem.c b/drivers/gpu/drm/virtio/virtgpu_gem.c
index 7db48d17ee3a..aefbb49481f1 100644
--- a/drivers/gpu/drm/virtio/virtgpu_gem.c
+++ b/drivers/gpu/drm/virtio/virtgpu_gem.c
@@ -99,21 +99,6 @@ int virtio_gpu_mode_dumb_create(struct drm_file *file_priv,
 	return ret;
 }
 
-int virtio_gpu_mode_dumb_mmap(struct drm_file *file_priv,
-			      struct drm_device *dev,
-			      uint32_t handle, uint64_t *offset_p)
-{
-	struct drm_gem_object *gobj;
-
-	BUG_ON(!offset_p);
-	gobj = drm_gem_object_lookup(file_priv, handle);
-	if (gobj == NULL)
-		return -ENOENT;
-	*offset_p = drm_vma_node_offset_addr(&gobj->vma_node);
-	drm_gem_object_put(gobj);
-	return 0;
-}
-
 int virtio_gpu_gem_object_open(struct drm_gem_object *obj,
 			       struct drm_file *file)
 {
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index e4f76f315550..112142f4b618 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -80,7 +80,7 @@ static int virtio_gpu_map_ioctl(struct drm_device *dev, void *data,
 	struct virtio_gpu_device *vgdev = dev->dev_private;
 	struct drm_virtgpu_map *virtio_gpu_map = data;
 
-	return virtio_gpu_mode_dumb_mmap(file, vgdev->ddev,
+	return drm_gem_dumb_map_offset(file, vgdev->ddev,
 					 virtio_gpu_map->handle,
 					 &virtio_gpu_map->offset);
 }
-- 
2.47.0

On 11/7/24 17:10, Peter Shkenev wrote:
> Currently, virtio uses its own dumb_map_offset implementation,
> virtio_gpu_mode_dumb_mmap. It works similarly to generic implementation,
> drm_gem_dumb_map_offset, and using the generic implementation is
> preferable (and making drivers to do so is a task stated on the DRM
> subsystem's TODO list).
> 
> Thus, make driver use the generic implementation. This includes
> VIRTGPU_MAP ioctl so it cannot be used to circumvent rules imposed by
> drm_gem_dumb_map_offset (imported objects cannot be mapped).
> 
> Signed-off-by: Peter Shkenev <mustela@erminea.space>
> ---
> Changes in v2:
>   - Remove excessive include of drm_gem.h from virtgpu_ioctl.h
>   - Remove obsoleted virtio_gpu_mode_dumb_mmap prototype from
>     virtgpu_drv.h
> 

Applied to misc-next, thanks!

-- 
Best regards,
Dmitry