1 /* $NetBSD: drm_syncobj.h,v 1.2 2021/12/18 23:45:46 riastradh Exp $ */ 2 3 /* 4 * Copyright © 2017 Red Hat 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the next 14 * paragraph) shall be included in all copies or substantial portions of the 15 * Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 23 * IN THE SOFTWARE. 24 * 25 * Authors: 26 * 27 */ 28 #ifndef __DRM_SYNCOBJ_H__ 29 #define __DRM_SYNCOBJ_H__ 30 31 #include <linux/dma-fence.h> 32 #include <linux/dma-fence-chain.h> 33 34 struct drm_file; 35 36 /** 37 * struct drm_syncobj - sync object. 38 * 39 * This structure defines a generic sync object which wraps a &dma_fence. 40 */ 41 struct drm_syncobj { 42 /** 43 * @refcount: Reference count of this object. 44 */ 45 struct kref refcount; 46 /** 47 * @fence: 48 * NULL or a pointer to the fence bound to this object. 49 * 50 * This field should not be used directly. Use drm_syncobj_fence_get() 51 * and drm_syncobj_replace_fence() instead. 52 */ 53 struct dma_fence __rcu *fence; 54 /** 55 * @cb_list: List of callbacks to call when the &fence gets replaced. 56 */ 57 struct list_head cb_list; 58 /** 59 * @lock: Protects &cb_list and write-locks &fence. 60 */ 61 spinlock_t lock; 62 /** 63 * @file: A file backing for this syncobj. 64 */ 65 struct file *file; 66 }; 67 68 void drm_syncobj_free(struct kref *kref); 69 70 /** 71 * drm_syncobj_get - acquire a syncobj reference 72 * @obj: sync object 73 * 74 * This acquires an additional reference to @obj. It is illegal to call this 75 * without already holding a reference. No locks required. 76 */ 77 static inline void 78 drm_syncobj_get(struct drm_syncobj *obj) 79 { 80 kref_get(&obj->refcount); 81 } 82 83 /** 84 * drm_syncobj_put - release a reference to a sync object. 85 * @obj: sync object. 86 */ 87 static inline void 88 drm_syncobj_put(struct drm_syncobj *obj) 89 { 90 kref_put(&obj->refcount, drm_syncobj_free); 91 } 92 93 /** 94 * drm_syncobj_fence_get - get a reference to a fence in a sync object 95 * @syncobj: sync object. 96 * 97 * This acquires additional reference to &drm_syncobj.fence contained in @obj, 98 * if not NULL. It is illegal to call this without already holding a reference. 99 * No locks required. 100 * 101 * Returns: 102 * Either the fence of @obj or NULL if there's none. 103 */ 104 static inline struct dma_fence * 105 drm_syncobj_fence_get(struct drm_syncobj *syncobj) 106 { 107 struct dma_fence *fence; 108 109 rcu_read_lock(); 110 fence = dma_fence_get_rcu_safe(&syncobj->fence); 111 rcu_read_unlock(); 112 113 return fence; 114 } 115 116 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private, 117 u32 handle); 118 void drm_syncobj_add_point(struct drm_syncobj *syncobj, 119 struct dma_fence_chain *chain, 120 struct dma_fence *fence, 121 uint64_t point); 122 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, 123 struct dma_fence *fence); 124 int drm_syncobj_find_fence(struct drm_file *file_private, 125 u32 handle, u64 point, u64 flags, 126 struct dma_fence **fence); 127 void drm_syncobj_free(struct kref *kref); 128 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, 129 struct dma_fence *fence); 130 int drm_syncobj_get_handle(struct drm_file *file_private, 131 struct drm_syncobj *syncobj, u32 *handle); 132 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd); 133 134 #endif 135