1/* 2 * Header file for reservations for dma-buf and ttm 3 * 4 * Copyright(C) 2011 Linaro Limited. All rights reserved. 5 * Copyright (C) 2012-2013 Canonical Ltd 6 * Copyright (C) 2012 Texas Instruments 7 * 8 * Authors: 9 * Rob Clark <robdclark@gmail.com> 10 * Maarten Lankhorst <maarten.lankhorst@canonical.com> 11 * Thomas Hellstrom <thellstrom-at-vmware-dot-com> 12 * 13 * Based on bo.c which bears the following copyright notice, 14 * but is dual licensed: 15 * 16 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 17 * All Rights Reserved. 18 * 19 * Permission is hereby granted, free of charge, to any person obtaining a 20 * copy of this software and associated documentation files (the 21 * "Software"), to deal in the Software without restriction, including 22 * without limitation the rights to use, copy, modify, merge, publish, 23 * distribute, sub license, and/or sell copies of the Software, and to 24 * permit persons to whom the Software is furnished to do so, subject to 25 * the following conditions: 26 * 27 * The above copyright notice and this permission notice (including the 28 * next paragraph) shall be included in all copies or substantial portions 29 * of the Software. 30 * 31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 32 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 33 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 34 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 35 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 36 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 37 * USE OR OTHER DEALINGS IN THE SOFTWARE. 38 */ 39#ifndef _LINUX_RESERVATION_H 40#define _LINUX_RESERVATION_H 41 42#include <linux/ww_mutex.h> 43#include <linux/fence.h> 44#include <linux/slab.h> 45#include <linux/seqlock.h> 46#include <linux/rcupdate.h> 47 48extern struct ww_class reservation_ww_class; 49extern struct lock_class_key reservation_seqcount_class; 50extern const char reservation_seqcount_string[]; 51 52struct reservation_object_list { 53 struct rcu_head rcu; 54 u32 shared_count, shared_max; 55 struct fence __rcu *shared[]; 56}; 57 58struct reservation_object { 59 struct ww_mutex lock; 60 seqcount_t seq; 61 62 struct fence __rcu *fence_excl; 63 struct reservation_object_list __rcu *fence; 64 struct reservation_object_list *staged; 65}; 66 67#define reservation_object_held(obj) lockdep_is_held(&(obj)->lock.base) 68#define reservation_object_assert_held(obj) \ 69 lockdep_assert_held(&(obj)->lock.base) 70 71static inline void 72reservation_object_init(struct reservation_object *obj) 73{ 74 ww_mutex_init(&obj->lock, &reservation_ww_class); 75 76 __seqcount_init(&obj->seq, reservation_seqcount_string, &reservation_seqcount_class); 77 RCU_INIT_POINTER(obj->fence, NULL); 78 RCU_INIT_POINTER(obj->fence_excl, NULL); 79 obj->staged = NULL; 80} 81 82static inline void 83reservation_object_fini(struct reservation_object *obj) 84{ 85 int i; 86 struct reservation_object_list *fobj; 87 struct fence *excl; 88 89 /* 90 * This object should be dead and all references must have 91 * been released to it, so no need to be protected with rcu. 92 */ 93 excl = rcu_dereference_protected(obj->fence_excl, 1); 94 if (excl) 95 fence_put(excl); 96 97 fobj = rcu_dereference_protected(obj->fence, 1); 98 if (fobj) { 99 for (i = 0; i < fobj->shared_count; ++i) 100 fence_put(rcu_dereference_protected(fobj->shared[i], 1)); 101 102 kfree(fobj); 103 } 104 kfree(obj->staged); 105 106 ww_mutex_destroy(&obj->lock); 107} 108 109static inline struct reservation_object_list * 110reservation_object_get_list(struct reservation_object *obj) 111{ 112 return rcu_dereference_protected(obj->fence, 113 reservation_object_held(obj)); 114} 115 116static inline struct fence * 117reservation_object_get_excl(struct reservation_object *obj) 118{ 119 return rcu_dereference_protected(obj->fence_excl, 120 reservation_object_held(obj)); 121} 122 123int reservation_object_reserve_shared(struct reservation_object *obj); 124void reservation_object_add_shared_fence(struct reservation_object *obj, 125 struct fence *fence); 126 127void reservation_object_add_excl_fence(struct reservation_object *obj, 128 struct fence *fence); 129 130int reservation_object_get_fences_rcu(struct reservation_object *obj, 131 struct fence **pfence_excl, 132 unsigned *pshared_count, 133 struct fence ***pshared); 134 135long reservation_object_wait_timeout_rcu(struct reservation_object *obj, 136 bool wait_all, bool intr, 137 unsigned long timeout); 138 139bool reservation_object_test_signaled_rcu(struct reservation_object *obj, 140 bool test_all); 141 142#endif /* _LINUX_RESERVATION_H */ 143