1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright 2013 Nexenta Systems, Inc. All rights reserved. 24 */ 25 26 #ifndef _SYS_MUTEX_H 27 #define _SYS_MUTEX_H 28 29 #include <sys/synch.h> /* lwp_mutex_t */ 30 31 #ifdef __cplusplus 32 extern "C" { 33 #endif 34 35 /* 36 * Public interface to mutual exclusion locks. See mutex(9F) for details. 37 * 38 * The basic mutex type is MUTEX_ADAPTIVE, which is expected to be used 39 * in almost all of the kernel. MUTEX_SPIN provides interrupt blocking 40 * and must be used in interrupt handlers above LOCK_LEVEL. The iblock 41 * cookie argument to mutex_init() encodes the interrupt level to block. 42 * The iblock cookie must be NULL for adaptive locks. 43 * 44 * MUTEX_DEFAULT is the type usually specified (except in drivers) to 45 * mutex_init(). It is identical to MUTEX_ADAPTIVE. 46 * 47 * MUTEX_DRIVER is always used by drivers. mutex_init() converts this to 48 * either MUTEX_ADAPTIVE or MUTEX_SPIN depending on the iblock cookie. 49 * 50 * Mutex statistics can be gathered on the fly, without rebooting or 51 * recompiling the kernel, via the lockstat driver (lockstat(7D)). 52 */ 53 typedef enum { 54 MUTEX_ADAPTIVE = 0, /* spin if owner is running, otherwise block */ 55 MUTEX_SPIN = 1, /* block interrupts and spin */ 56 MUTEX_DRIVER = 4, /* driver (DDI) mutex */ 57 MUTEX_DEFAULT = 6 /* kernel default mutex */ 58 } kmutex_type_t; 59 60 struct _kmutex { 61 lwp_mutex_t m_lock; 62 void *m_owner; 63 }; 64 typedef struct _kmutex kmutex_t; 65 66 #if defined(_KERNEL) || defined(_FAKE_KERNEL) 67 /* See the real sys/mutex.h */ 68 typedef struct pad_mutex { 69 kmutex_t pad_mutex; 70 #ifdef _LP64 71 char pad_pad[64 - sizeof (kmutex_t)]; 72 #endif 73 } pad_mutex_t; 74 #endif /* _KERNEL */ 75 76 #define MUTEX_HELD(x) (mutex_owned(x)) 77 #define MUTEX_NOT_HELD(x) (!mutex_owned(x) || panicstr) 78 79 /* 80 * We're simulating the kernel mutex API here, and the 81 * user-level has a different signature, so rename. 82 */ 83 #define mutex_init kmutex_init 84 #define mutex_destroy kmutex_destroy 85 86 extern void kmutex_init(kmutex_t *, char *, kmutex_type_t, void *); 87 extern void kmutex_destroy(kmutex_t *); 88 89 extern void mutex_enter(kmutex_t *); 90 extern int mutex_tryenter(kmutex_t *); 91 extern void mutex_exit(kmutex_t *); 92 extern int mutex_owned(const kmutex_t *); 93 94 extern void *mutex_owner(const kmutex_t *); 95 96 #ifdef __cplusplus 97 } 98 #endif 99 100 #endif /* _SYS_MUTEX_H */ 101