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 #include <linux/dma-fence-chain.h> 31 32 struct drm_file; 33 34 /** 35 * struct drm_syncobj - sync object. 36 * 37 * This structure defines a generic sync object which wraps a &dma_fence. 38 */ 39 struct drm_syncobj { 40 /** 41 * @refcount: Reference count of this object. 42 */ 43 struct kref refcount; 44 /** 45 * @fence: 46 * NULL or a pointer to the fence bound to this object. 47 * 48 * This field should not be used directly. Use drm_syncobj_fence_get() 49 * and drm_syncobj_replace_fence() instead. 50 */ 51 struct dma_fence __rcu *fence; 52 /** 53 * @cb_list: List of callbacks to call when the &fence gets replaced. 54 */ 55 struct list_head cb_list; 56 /** 57 * @lock: Protects &cb_list and write-locks &fence. 58 */ 59 spinlock_t lock; 60 /** 61 * @file: A file backing for this syncobj. 62 */ 63 struct file *file; 64 }; 65 66 void drm_syncobj_free(struct kref *kref); 67 68 /** 69 * drm_syncobj_get - acquire a syncobj reference 70 * @obj: sync object 71 * 72 * This acquires an additional reference to @obj. It is illegal to call this 73 * without already holding a reference. No locks required. 74 */ 75 static inline void 76 drm_syncobj_get(struct drm_syncobj *obj) 77 { 78 kref_get(&obj->refcount); 79 } 80 81 /** 82 * drm_syncobj_put - release a reference to a sync object. 83 * @obj: sync object. 84 */ 85 static inline void 86 drm_syncobj_put(struct drm_syncobj *obj) 87 { 88 kref_put(&obj->refcount, drm_syncobj_free); 89 } 90 91 /** 92 * drm_syncobj_fence_get - get a reference to a fence in a sync object 93 * @syncobj: sync object. 94 * 95 * This acquires additional reference to &drm_syncobj.fence contained in @obj, 96 * if not NULL. It is illegal to call this without already holding a reference. 97 * No locks required. 98 * 99 * Returns: 100 * Either the fence of @obj or NULL if there's none. 101 */ 102 static inline struct dma_fence * 103 drm_syncobj_fence_get(struct drm_syncobj *syncobj) 104 { 105 struct dma_fence *fence; 106 107 rcu_read_lock(); 108 fence = dma_fence_get_rcu_safe(&syncobj->fence); 109 rcu_read_unlock(); 110 111 return fence; 112 } 113 114 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private, 115 u32 handle); 116 void drm_syncobj_add_point(struct drm_syncobj *syncobj, 117 struct dma_fence_chain *chain, 118 struct dma_fence *fence, 119 uint64_t point); 120 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, 121 struct dma_fence *fence); 122 int drm_syncobj_find_fence(struct drm_file *file_private, 123 u32 handle, u64 point, u64 flags, 124 struct dma_fence **fence); 125 void drm_syncobj_free(struct kref *kref); 126 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, 127 struct dma_fence *fence); 128 int drm_syncobj_get_handle(struct drm_file *file_private, 129 struct drm_syncobj *syncobj, u32 *handle); 130 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd); 131 132 #endif 133