Drivers may want to set their own callbacks for a VM area. Only set TTM's callbacks if the vm_ops field is clear.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index b31b18058965..bf4a213bc66c 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -534,7 +534,12 @@ static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_device *bdev,
static void ttm_bo_mmap_vma_setup(struct ttm_buffer_object *bo, struct vm_area_struct *vma) { - vma->vm_ops = &ttm_bo_vm_ops; + /* + * Drivers may want to override the vm_ops field. Otherwise we + * use TTM's default callbacks. + */ + if (!vma->vm_ops) + vma->vm_ops = &ttm_bo_vm_ops;
/* * Note: We're transferring the bo reference to