1 /* 2 * Copyright © 2017 Red Hat 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 * Authors: 24 * 25 */ 26 #ifndef __DRM_SYNCOBJ_H__ 27 #define __DRM_SYNCOBJ_H__ 28 29 #include "linux/dma-fence.h" 30 31 struct drm_syncobj_cb; 32 33 /** 34 * struct drm_syncobj - sync object. 35 * 36 * This structure defines a generic sync object which wraps a dma fence. 37 */ 38 struct drm_syncobj { 39 /** 40 * @refcount: 41 * 42 * Reference count of this object. 43 */ 44 struct kref refcount; 45 /** 46 * @fence: 47 * NULL or a pointer to the fence bound to this object. 48 * 49 * This field should not be used directly. Use drm_syncobj_fence_get 50 * and drm_syncobj_replace_fence instead. 51 */ 52 struct dma_fence *fence; 53 /** 54 * @cb_list: 55 * List of callbacks to call when the fence gets replaced 56 */ 57 struct list_head cb_list; 58 /** 59 * @lock: 60 * locks cb_list and write-locks fence. 61 */ 62 spinlock_t lock; 63 /** 64 * @file: 65 * a file backing for this syncobj. 66 */ 67 struct file *file; 68 }; 69 70 typedef void (*drm_syncobj_func_t)(struct drm_syncobj *syncobj, 71 struct drm_syncobj_cb *cb); 72 73 /** 74 * struct drm_syncobj_cb - callback for drm_syncobj_add_callback 75 * @node: used by drm_syncob_add_callback to append this struct to 76 * syncobj::cb_list 77 * @func: drm_syncobj_func_t to call 78 * 79 * This struct will be initialized by drm_syncobj_add_callback, additional 80 * data can be passed along by embedding drm_syncobj_cb in another struct. 81 * The callback will get called the next time drm_syncobj_replace_fence is 82 * called. 83 */ 84 struct drm_syncobj_cb { 85 struct list_head node; 86 drm_syncobj_func_t func; 87 }; 88 89 void drm_syncobj_free(struct kref *kref); 90 91 /** 92 * drm_syncobj_get - acquire a syncobj reference 93 * @obj: sync object 94 * 95 * This acquires additional reference to @obj. It is illegal to call this 96 * without already holding a reference. No locks required. 97 */ 98 static inline void 99 drm_syncobj_get(struct drm_syncobj *obj) 100 { 101 kref_get(&obj->refcount); 102 } 103 104 /** 105 * drm_syncobj_put - release a reference to a sync object. 106 * @obj: sync object. 107 */ 108 static inline void 109 drm_syncobj_put(struct drm_syncobj *obj) 110 { 111 kref_put(&obj->refcount, drm_syncobj_free); 112 } 113 114 static inline struct dma_fence * 115 drm_syncobj_fence_get(struct drm_syncobj *syncobj) 116 { 117 struct dma_fence *fence; 118 119 rcu_read_lock(); 120 fence = dma_fence_get_rcu_safe(&syncobj->fence); 121 rcu_read_unlock(); 122 123 return fence; 124 } 125 126 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private, 127 u32 handle); 128 void drm_syncobj_add_callback(struct drm_syncobj *syncobj, 129 struct drm_syncobj_cb *cb, 130 drm_syncobj_func_t func); 131 void drm_syncobj_remove_callback(struct drm_syncobj *syncobj, 132 struct drm_syncobj_cb *cb); 133 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, 134 struct dma_fence *fence); 135 int drm_syncobj_find_fence(struct drm_file *file_private, 136 u32 handle, 137 struct dma_fence **fence); 138 void drm_syncobj_free(struct kref *kref); 139 140 #endif 141