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: Reference count of this object. 41 */ 42 struct kref refcount; 43 /** 44 * @fence: 45 * NULL or a pointer to the fence bound to this object. 46 * 47 * This field should not be used directly. Use drm_syncobj_fence_get() 48 * and drm_syncobj_replace_fence() instead. 49 */ 50 struct dma_fence __rcu *fence; 51 /** 52 * @cb_list: List of callbacks to call when the &fence gets replaced. 53 */ 54 struct list_head cb_list; 55 /** 56 * @lock: Protects &cb_list and write-locks &fence. 57 */ 58 spinlock_t lock; 59 /** 60 * @file: A file backing for this syncobj. 61 */ 62 struct file *file; 63 }; 64 65 typedef void (*drm_syncobj_func_t)(struct drm_syncobj *syncobj, 66 struct drm_syncobj_cb *cb); 67 68 /** 69 * struct drm_syncobj_cb - callback for drm_syncobj_add_callback 70 * @node: used by drm_syncob_add_callback to append this struct to 71 * &drm_syncobj.cb_list 72 * @func: drm_syncobj_func_t to call 73 * 74 * This struct will be initialized by drm_syncobj_add_callback, additional 75 * data can be passed along by embedding drm_syncobj_cb in another struct. 76 * The callback will get called the next time drm_syncobj_replace_fence is 77 * called. 78 */ 79 struct drm_syncobj_cb { 80 struct list_head node; 81 drm_syncobj_func_t func; 82 }; 83 84 void drm_syncobj_free(struct kref *kref); 85 86 /** 87 * drm_syncobj_get - acquire a syncobj reference 88 * @obj: sync object 89 * 90 * This acquires an additional reference to @obj. It is illegal to call this 91 * without already holding a reference. No locks required. 92 */ 93 static inline void 94 drm_syncobj_get(struct drm_syncobj *obj) 95 { 96 kref_get(&obj->refcount); 97 } 98 99 /** 100 * drm_syncobj_put - release a reference to a sync object. 101 * @obj: sync object. 102 */ 103 static inline void 104 drm_syncobj_put(struct drm_syncobj *obj) 105 { 106 kref_put(&obj->refcount, drm_syncobj_free); 107 } 108 109 /** 110 * drm_syncobj_fence_get - get a reference to a fence in a sync object 111 * @syncobj: sync object. 112 * 113 * This acquires additional reference to &drm_syncobj.fence contained in @obj, 114 * if not NULL. It is illegal to call this without already holding a reference. 115 * No locks required. 116 * 117 * Returns: 118 * Either the fence of @obj or NULL if there's none. 119 */ 120 static inline struct dma_fence * 121 drm_syncobj_fence_get(struct drm_syncobj *syncobj) 122 { 123 struct dma_fence *fence; 124 125 rcu_read_lock(); 126 fence = dma_fence_get_rcu_safe(&syncobj->fence); 127 rcu_read_unlock(); 128 129 return fence; 130 } 131 132 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private, 133 u32 handle); 134 void drm_syncobj_add_callback(struct drm_syncobj *syncobj, 135 struct drm_syncobj_cb *cb, 136 drm_syncobj_func_t func); 137 void drm_syncobj_remove_callback(struct drm_syncobj *syncobj, 138 struct drm_syncobj_cb *cb); 139 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, 140 struct dma_fence *fence); 141 int drm_syncobj_find_fence(struct drm_file *file_private, 142 u32 handle, 143 struct dma_fence **fence); 144 void drm_syncobj_free(struct kref *kref); 145 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, 146 struct dma_fence *fence); 147 int drm_syncobj_get_handle(struct drm_file *file_private, 148 struct drm_syncobj *syncobj, u32 *handle); 149 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd); 150 151 #endif 152