From 89c815ef07a1db0ac2cc09d06cb2d5c3d86d6322 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Thu, 21 Jun 2018 15:21:35 +0200 Subject: [PATCH] drm/ttm: Introduce ttm_bo_get() and ttm_bo_put() for ref counting MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The TTM buffer-object interface provides ttm_bo_reference() and ttm_bo_unref() for managing reference counts. Replacing them with ttm_bo_get() and ttm_bo_put() aligns the API with conventions used throughout the Linux kernel. The implementation of ttm_bo_unref() clears the supplied pointer to NULL. This leads to workarounds where the caller saves the pointer's value before de-referencing the BO. ttm_bo_put() does not clear the supplied pointer. Signed-off-by: Thomas Zimmermann Reviewed-by: Christian König Signed-off-by: Alex Deucher --- drivers/gpu/drm/ttm/ttm_bo.c | 8 +++++++- include/drm/ttm/ttm_bo_api.h | 25 ++++++++++++++++++++++++- 2 files changed, 31 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 5142dcb8ce39..183e67c4197a 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -587,12 +587,18 @@ static void ttm_bo_release(struct kref *kref) kref_put(&bo->list_kref, ttm_bo_release_list); } +void ttm_bo_put(struct ttm_buffer_object *bo) +{ + kref_put(&bo->kref, ttm_bo_release); +} +EXPORT_SYMBOL(ttm_bo_put); + void ttm_bo_unref(struct ttm_buffer_object **p_bo) { struct ttm_buffer_object *bo = *p_bo; *p_bo = NULL; - kref_put(&bo->kref, ttm_bo_release); + ttm_bo_put(bo); } EXPORT_SYMBOL(ttm_bo_unref); diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h index c67977aa1a0e..a01ba2032f0e 100644 --- a/include/drm/ttm/ttm_bo_api.h +++ b/include/drm/ttm/ttm_bo_api.h @@ -283,18 +283,30 @@ struct ttm_operation_ctx { /* when serving page fault or suspend, allow alloc anyway */ #define TTM_OPT_FLAG_FORCE_ALLOC 0x2 +/** + * ttm_bo_get - reference a struct ttm_buffer_object + * + * @bo: The buffer object. + */ +static inline void ttm_bo_get(struct ttm_buffer_object *bo) +{ + kref_get(&bo->kref); +} + /** * ttm_bo_reference - reference a struct ttm_buffer_object * * @bo: The buffer object. * * Returns a refcounted pointer to a buffer object. + * + * This function is deprecated. Use @ttm_bo_get instead. */ static inline struct ttm_buffer_object * ttm_bo_reference(struct ttm_buffer_object *bo) { - kref_get(&bo->kref); + ttm_bo_get(bo); return bo; } @@ -345,12 +357,23 @@ int ttm_bo_validate(struct ttm_buffer_object *bo, struct ttm_placement *placement, struct ttm_operation_ctx *ctx); +/** + * ttm_bo_put + * + * @bo: The buffer object. + * + * Unreference a buffer object. + */ +void ttm_bo_put(struct ttm_buffer_object *bo); + /** * ttm_bo_unref * * @bo: The buffer object. * * Unreference and clear a pointer to a buffer object. + * + * This function is deprecated. Use @ttm_bo_put instead. */ void ttm_bo_unref(struct ttm_buffer_object **bo);