LXR linux/include/drm/drm

   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
  32struct 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 */
  39struct 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
  66void 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 */
  75static inline void
  76drm_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 */
  85static inline void
  86drm_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 */
 102static inline struct dma_fence *
 103drm_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
 114struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
 115                                     u32 handle);
 116void drm_syncobj_add_point(struct drm_syncobj *syncobj,
 117                           struct dma_fence_chain *chain,
 118                           struct dma_fence *fence,
 119                           uint64_t point);
 120void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 121                               struct dma_fence *fence);
 122int drm_syncobj_find_fence(struct drm_file *file_private,
 123                           u32 handle, u64 point, u64 flags,
 124                           struct dma_fence **fence);
 125void drm_syncobj_free(struct kref *kref);
 126int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 127                       struct dma_fence *fence);
 128int drm_syncobj_get_handle(struct drm_file *file_private,
 129                           struct drm_syncobj *syncobj, u32 *handle);
 130int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd);
 131
 132#endif
 133