/* SPDX-License-Identifier: GPL-2.0 OR MIT */ #ifndef __DRM_EXEC_H__#define __DRM_EXEC_H__ #include <linux/compiler.h>#include <linux/ww_mutex.h> #define DRM_EXEC_INTERRUPTIBLE_WAIT	BIT(0)#define DRM_EXEC_IGNORE_DUPLICATES	BIT(1) /* * Dummy value used to initially enter the retry loop. * internal use only. */#define DRM_EXEC_DUMMY ((void *)~0) struct drm_gem_object; /** * struct drm_exec - Execution context */struct drm_exec {	/**	 * @flags: Flags to control locking behavior	 */	u32                     flags; 	/**	 * @ticket: WW ticket used for acquiring locks	 */	struct ww_acquire_ctx	ticket; 	/**	 * @num_objects: number of objects locked	 */	unsigned int		num_objects; 	/**	 * @max_objects: maximum objects in array	 */	unsigned int		max_objects; 	/**	 * @objects: array of the locked objects	 */	struct drm_gem_object	**objects; 	/**	 * @contended: contended GEM object we backed off for	 */	struct drm_gem_object	*contended; 	/**	 * @prelocked: already locked GEM object due to contention	 */	struct drm_gem_object *prelocked;}; /** * drm_exec_obj() - Return the object for a give drm_exec index * @exec: Pointer to the drm_exec context * @index: The index. * * Return: Pointer to the locked object corresponding to @index if * index is within the number of locked objects. NULL otherwise. */static inline struct drm_gem_object *drm_exec_obj(struct drm_exec *exec, unsigned long index){	return index < exec->num_objects ? exec->objects[index] : NULL;} /* Helper for drm_exec_for_each_locked_object(). Internal use only. */#define __drm_exec_for_each_locked_object(exec, obj, __index)		\	for (unsigned long __index = 0; ((obj) = drm_exec_obj(exec, __index)); ++__index)/** * drm_exec_for_each_locked_object - iterate over all the locked objects * @exec: drm_exec object * @obj: the current GEM object * * Iterate over all the locked GEM objects inside the drm_exec object. */#define drm_exec_for_each_locked_object(exec, obj)			\	__drm_exec_for_each_locked_object(exec, obj, __UNIQUE_ID(drm_exec)) /* Helper for drm_exec_for_each_locked_object_reverse(). Internal use only. */#define __drm_exec_for_each_locked_object_reverse(exec, obj, __index)	\	for (unsigned long __index = (exec)->num_objects - 1;		\	     ((obj) = drm_exec_obj(exec, __index)); --__index)/** * drm_exec_for_each_locked_object_reverse - iterate over all the locked * objects in reverse locking order * @exec: drm_exec object * @obj: the current GEM object * * Iterate over all the locked GEM objects inside the drm_exec object in * reverse locking order. Note that the internal index may wrap around, * but that will be caught by drm_exec_obj(), returning a NULL object. */#define drm_exec_for_each_locked_object_reverse(exec, obj)		\	__drm_exec_for_each_locked_object_reverse(exec, obj, __UNIQUE_ID(drm_exec)) /** * drm_exec_until_all_locked - loop until all GEM objects are locked * @exec: drm_exec object * * Core functionality of the drm_exec object. Loops until all GEM objects are * locked and no more contention exists. At the beginning of the loop it is * guaranteed that no GEM object is locked. * * A global label name drm_exec_retry is used, if you need to use more than one * instance of this macro in the same function the label needs to be made local * to the block with the __label__ keyword. */#define drm_exec_until_all_locked(exec)					\	for (bool const __maybe_unused __drm_exec_loop = false;		\	     drm_exec_cleanup(exec);)					\		if (false) {						\drm_exec_retry: __maybe_unused;						\			continue;					\		} else /** * drm_exec_retry_on_contention - restart the loop to grap all locks * @exec: drm_exec object * * Control flow helper to continue when a contention was detected and we need to * clean up and re-start the loop to prepare all GEM objects. * The __drm_exec_loop check exists to prevent usage outside of an * drm_exec_until_all_locked() loop. */#define drm_exec_retry_on_contention(exec)			\	do {							\		if (unlikely(drm_exec_is_contended(exec)))	\			goto drm_exec_retry;			\	} while (__drm_exec_loop) /** * drm_exec_is_contended - check for contention * @exec: drm_exec object * * Returns true if the drm_exec object has run into some contention while * locking a GEM object and needs to clean up. */static inline bool drm_exec_is_contended(struct drm_exec *exec){	return !!exec->contended;} /** * drm_exec_retry() - Unconditionally restart the loop to grab all locks. * @exec: drm_exec object * * Unconditionally retry the loop to lock all objects. For consistency, * the exec object needs to be newly initialized. * The __drm_exec_loop check exists to prevent usage outside of an * drm_exec_until_all_locked() loop. */#define drm_exec_retry(_exec)					\	do {							\		WARN_ON((_exec)->contended != DRM_EXEC_DUMMY);	\		goto drm_exec_retry;				\	} while (__drm_exec_loop) /** * drm_exec_ticket - return the ww_acquire_ctx for this exec context * @exec: drm_exec object * * Return: Pointer to the ww_acquire_ctx embedded in @exec. */static inline struct ww_acquire_ctx *drm_exec_ticket(struct drm_exec *exec){	return &exec->ticket;} void drm_exec_init(struct drm_exec *exec, u32 flags, unsigned nr);void drm_exec_fini(struct drm_exec *exec);bool drm_exec_cleanup(struct drm_exec *exec);int drm_exec_lock_obj(struct drm_exec *exec, struct drm_gem_object *obj);void drm_exec_unlock_obj(struct drm_exec *exec, struct drm_gem_object *obj);int drm_exec_prepare_obj(struct drm_exec *exec, struct drm_gem_object *obj,			 unsigned int num_fences);int drm_exec_prepare_array(struct drm_exec *exec,			   struct drm_gem_object **objects,			   unsigned int num_objects,			   unsigned int num_fences); #endif