1 /* $NetBSD: spinlock.h,v 1.2 2014/03/18 18:20:43 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _LINUX_SPINLOCK_H_ 33 #define _LINUX_SPINLOCK_H_ 34 35 #include <sys/cdefs.h> 36 #include <sys/mutex.h> 37 38 typedef struct spinlock { 39 kmutex_t sl_lock; 40 } spinlock_t; 41 42 static inline int 43 spin_is_locked(spinlock_t *spinlock) 44 { 45 return mutex_owned(&spinlock->sl_lock); 46 } 47 48 static inline void 49 spin_lock(spinlock_t *spinlock) 50 { 51 mutex_enter(&spinlock->sl_lock); 52 } 53 54 static inline void 55 spin_unlock(spinlock_t *spinlock) 56 { 57 mutex_exit(&spinlock->sl_lock); 58 } 59 60 static inline void 61 spin_lock_irq(spinlock_t *spinlock) 62 { 63 spin_lock(spinlock); 64 } 65 66 static inline void 67 spin_unlock_irq(spinlock_t *spinlock) 68 { 69 spin_unlock(spinlock); 70 } 71 72 /* Must be a macro because the second argument is to be assigned. */ 73 #define spin_lock_irqsave(SPINLOCK, FLAGS) \ 74 do { \ 75 (FLAGS) = 0; \ 76 mutex_enter(&((spinlock_t *)(SPINLOCK))->sl_lock); \ 77 } while (0) 78 79 static inline void 80 spin_unlock_irqrestore(spinlock_t *spinlock, unsigned long __unused flags) 81 { 82 mutex_exit(&spinlock->sl_lock); 83 } 84 85 static inline void 86 spin_lock_init(spinlock_t *spinlock) 87 { 88 /* XXX What's the right IPL? IPL_DRM...? */ 89 mutex_init(&spinlock->sl_lock, MUTEX_DEFAULT, IPL_VM); 90 } 91 92 /* 93 * XXX Linux doesn't ever destroy spin locks, it seems. We'll have to 94 * kludge it up. 95 */ 96 97 static inline void 98 spin_lock_destroy(spinlock_t *spinlock) 99 { 100 mutex_destroy(&spinlock->sl_lock); 101 } 102 103 /* This is a macro to make the panic message clearer. */ 104 #define assert_spin_locked(spinlock) \ 105 KASSERT(mutex_owned(&(spinlock)->sl_lock)) 106 107 #endif /* _LINUX_SPINLOCK_H_ */ 108