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 <rob.clark@linaro.org> 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 48 extern struct ww_class reservation_ww_class; 49 extern struct lock_class_key reservation_seqcount_class; 50 extern const char reservation_seqcount_string[]; 51 52 struct reservation_object { 53 struct ww_mutex lock; 54 seqcount_t seq; 55 56 struct fence *fence_excl; 57 }; 58 59 #define reservation_object_held(obj) lockdep_is_held(&(obj)->lock.base) 60 #define reservation_object_assert_held(obj) \ 61 lockdep_assert_held(&(obj)->lock.base) 62 63 /** 64 * reservation_object_init - initialize a reservation object 65 * @obj: the reservation object 66 */ 67 static inline void 68 reservation_object_init(struct reservation_object *obj) 69 { 70 ww_mutex_init(&obj->lock, &reservation_ww_class); 71 72 __seqcount_init(&obj->seq, reservation_seqcount_string, &reservation_seqcount_class); 73 } 74 75 /** 76 * reservation_object_fini - destroys a reservation object 77 * @obj: the reservation object 78 */ 79 static inline void 80 reservation_object_fini(struct reservation_object *obj) 81 { 82 ww_mutex_destroy(&obj->lock); 83 } 84 85 #endif /* _LINUX_RESERVATION_H */ 86