1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */ 2 3 #ifndef __DRM_EXEC_H__ 4 #define __DRM_EXEC_H__ 5 6 #include <linux/compiler.h> 7 #include <linux/ww_mutex.h> 8 9 #define DRM_EXEC_INTERRUPTIBLE_WAIT BIT(0) 10 #define DRM_EXEC_IGNORE_DUPLICATES BIT(1) 11 12 struct drm_gem_object; 13 14 /** 15 * struct drm_exec - Execution context 16 */ 17 struct drm_exec { 18 /** 19 * @flags: Flags to control locking behavior 20 */ 21 u32 flags; 22 23 /** 24 * @ticket: WW ticket used for acquiring locks 25 */ 26 struct ww_acquire_ctx ticket; 27 28 /** 29 * @num_objects: number of objects locked 30 */ 31 unsigned int num_objects; 32 33 /** 34 * @max_objects: maximum objects in array 35 */ 36 unsigned int max_objects; 37 38 /** 39 * @objects: array of the locked objects 40 */ 41 struct drm_gem_object **objects; 42 43 /** 44 * @contended: contended GEM object we backed off for 45 */ 46 struct drm_gem_object *contended; 47 48 /** 49 * @prelocked: already locked GEM object due to contention 50 */ 51 struct drm_gem_object *prelocked; 52 }; 53 54 /** 55 * drm_exec_obj() - Return the object for a give drm_exec index 56 * @exec: Pointer to the drm_exec context 57 * @index: The index. 58 * 59 * Return: Pointer to the locked object corresponding to @index if 60 * index is within the number of locked objects. NULL otherwise. 61 */ 62 static inline struct drm_gem_object * drm_exec_obj(struct drm_exec * exec,unsigned long index)63 drm_exec_obj(struct drm_exec *exec, unsigned long index) 64 { 65 return index < exec->num_objects ? exec->objects[index] : NULL; 66 } 67 68 /** 69 * drm_exec_for_each_locked_object - iterate over all the locked objects 70 * @exec: drm_exec object 71 * @index: unsigned long index for the iteration 72 * @obj: the current GEM object 73 * 74 * Iterate over all the locked GEM objects inside the drm_exec object. 75 */ 76 #define drm_exec_for_each_locked_object(exec, index, obj) \ 77 for ((index) = 0; ((obj) = drm_exec_obj(exec, index)); ++(index)) 78 79 /** 80 * drm_exec_for_each_locked_object_reverse - iterate over all the locked 81 * objects in reverse locking order 82 * @exec: drm_exec object 83 * @index: unsigned long index for the iteration 84 * @obj: the current GEM object 85 * 86 * Iterate over all the locked GEM objects inside the drm_exec object in 87 * reverse locking order. Note that @index may go below zero and wrap, 88 * but that will be caught by drm_exec_obj(), returning a NULL object. 89 */ 90 #define drm_exec_for_each_locked_object_reverse(exec, index, obj) \ 91 for ((index) = (exec)->num_objects - 1; \ 92 ((obj) = drm_exec_obj(exec, index)); --(index)) 93 94 /** 95 * drm_exec_until_all_locked - loop until all GEM objects are locked 96 * @exec: drm_exec object 97 * 98 * Core functionality of the drm_exec object. Loops until all GEM objects are 99 * locked and no more contention exists. At the beginning of the loop it is 100 * guaranteed that no GEM object is locked. 101 * 102 * Since labels can't be defined local to the loops body we use a jump pointer 103 * to make sure that the retry is only used from within the loops body. 104 */ 105 #define drm_exec_until_all_locked(exec) \ 106 __PASTE(__drm_exec_, __LINE__): \ 107 for (void *__drm_exec_retry_ptr; ({ \ 108 __drm_exec_retry_ptr = &&__PASTE(__drm_exec_, __LINE__);\ 109 (void)__drm_exec_retry_ptr; \ 110 drm_exec_cleanup(exec); \ 111 });) 112 113 /** 114 * drm_exec_retry_on_contention - restart the loop to grap all locks 115 * @exec: drm_exec object 116 * 117 * Control flow helper to continue when a contention was detected and we need to 118 * clean up and re-start the loop to prepare all GEM objects. 119 */ 120 #define drm_exec_retry_on_contention(exec) \ 121 do { \ 122 if (unlikely(drm_exec_is_contended(exec))) \ 123 goto *__drm_exec_retry_ptr; \ 124 } while (0) 125 126 /** 127 * drm_exec_is_contended - check for contention 128 * @exec: drm_exec object 129 * 130 * Returns true if the drm_exec object has run into some contention while 131 * locking a GEM object and needs to clean up. 132 */ drm_exec_is_contended(struct drm_exec * exec)133 static inline bool drm_exec_is_contended(struct drm_exec *exec) 134 { 135 return !!exec->contended; 136 } 137 138 void drm_exec_init(struct drm_exec *exec, u32 flags, unsigned nr); 139 void drm_exec_fini(struct drm_exec *exec); 140 bool drm_exec_cleanup(struct drm_exec *exec); 141 int drm_exec_lock_obj(struct drm_exec *exec, struct drm_gem_object *obj); 142 void drm_exec_unlock_obj(struct drm_exec *exec, struct drm_gem_object *obj); 143 int drm_exec_prepare_obj(struct drm_exec *exec, struct drm_gem_object *obj, 144 unsigned int num_fences); 145 int drm_exec_prepare_array(struct drm_exec *exec, 146 struct drm_gem_object **objects, 147 unsigned int num_objects, 148 unsigned int num_fences); 149 150 #endif 151