1 /* 2 * Copyright (c) 2014-2020 François Tigeot <ftigeot@wolfpond.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef _LINUX_MUTEX_H_ 28 #define _LINUX_MUTEX_H_ 29 30 #include <asm/current.h> 31 #include <linux/list.h> 32 #include <linux/lockdep.h> 33 #include <linux/atomic.h> 34 #include <asm/processor.h> 35 36 #define mutex_is_locked(lock) (lockinuse(lock)) 37 38 #define mutex_lock(lock) lockmgr(lock, LK_EXCLUSIVE) 39 #define mutex_unlock(lock) lockmgr(lock, LK_RELEASE) 40 41 #define mutex_trylock(lock) lockmgr_try(lock, LK_EXCLUSIVE) 42 43 static inline int 44 mutex_lock_interruptible(struct lock *lock) 45 { 46 if (lockmgr(lock, LK_EXCLUSIVE|LK_SLEEPFAIL|LK_PCATCH)) 47 return -EINTR; 48 49 return 0; 50 } 51 52 #define DEFINE_MUTEX(mutex) \ 53 struct lock mutex; \ 54 LOCK_SYSINIT(mutex, &mutex, "lmutex", LK_CANRECURSE) 55 56 static inline void 57 mutex_destroy(struct lock *mutex) 58 { 59 lockuninit(mutex); 60 } 61 62 #define mutex_lock_nested(lock, unused) mutex_lock(lock) 63 64 enum mutex_trylock_recursive_enum { 65 MUTEX_TRYLOCK_FAILED = 0, 66 MUTEX_TRYLOCK_SUCCESS = 1, 67 MUTEX_TRYLOCK_RECURSIVE, 68 }; 69 70 static inline enum mutex_trylock_recursive_enum 71 mutex_trylock_recursive(struct lock *lock) 72 { 73 if (lockowned(lock)) 74 return MUTEX_TRYLOCK_RECURSIVE; 75 76 if (mutex_trylock(lock)) 77 return MUTEX_TRYLOCK_SUCCESS; 78 79 return MUTEX_TRYLOCK_FAILED; 80 } 81 82 #endif /* _LINUX_MUTEX_H_ */ 83