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 * Copyright 2017 RackTop Systems. 25 */ 26 27 #ifndef _SYS_MUTEX_H 28 #define _SYS_MUTEX_H 29 30 #include <sys/synch.h> /* lwp_mutex_t */ 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 /* 37 * Public interface to mutual exclusion locks. See mutex(9F) for details. 38 * 39 * The basic mutex type is MUTEX_ADAPTIVE, which is expected to be used 40 * in almost all of the kernel. MUTEX_SPIN provides interrupt blocking 41 * and must be used in interrupt handlers above LOCK_LEVEL. The iblock 42 * cookie argument to mutex_init() encodes the interrupt level to block. 43 * The iblock cookie must be NULL for adaptive locks. 44 * 45 * MUTEX_DEFAULT is the type usually specified (except in drivers) to 46 * mutex_init(). It is identical to MUTEX_ADAPTIVE. 47 * 48 * MUTEX_DRIVER is always used by drivers. mutex_init() converts this to 49 * either MUTEX_ADAPTIVE or MUTEX_SPIN depending on the iblock cookie. 50 * 51 * Mutex statistics can be gathered on the fly, without rebooting or 52 * recompiling the kernel, via the lockstat driver (lockstat(7D)). 53 */ 54 typedef enum { 55 MUTEX_ADAPTIVE = 0, /* spin if owner is running, otherwise block */ 56 MUTEX_SPIN = 1, /* block interrupts and spin */ 57 MUTEX_DRIVER = 4, /* driver (DDI) mutex */ 58 MUTEX_DEFAULT = 6 /* kernel default mutex */ 59 } kmutex_type_t; 60 61 struct _kmutex { 62 lwp_mutex_t m_lock; 63 void *m_owner; 64 }; 65 typedef struct _kmutex kmutex_t; 66 67 #if defined(_KERNEL) || defined(_FAKE_KERNEL) 68 /* See the real sys/mutex.h */ 69 typedef struct pad_mutex { 70 kmutex_t pad_mutex; 71 #ifdef _LP64 72 char pad_pad[64 - sizeof (kmutex_t)]; 73 #endif 74 } pad_mutex_t; 75 #endif /* _KERNEL */ 76 77 extern char *volatile panicstr; /* panic string pointer */ 78 79 #define MUTEX_HELD(x) (mutex_owned(x)) 80 #define MUTEX_NOT_HELD(x) (!mutex_owned(x) || panicstr) 81 82 /* 83 * We're simulating the kernel mutex API here, and the 84 * user-level has a different signature, so rename. 85 */ 86 #define mutex_init kmutex_init 87 #define mutex_destroy kmutex_destroy 88 89 /* 90 * We want to avoid binding against the versions of these 91 * functions in libc which causes bad things to happen. 92 */ 93 #define mutex_enter kmutex_enter 94 #define mutex_exit kmutex_exit 95 96 extern void kmutex_init(kmutex_t *, char *, kmutex_type_t, void *); 97 extern void kmutex_destroy(kmutex_t *); 98 99 extern void kmutex_enter(kmutex_t *); 100 extern void kmutex_exit(kmutex_t *); 101 102 extern int mutex_tryenter(kmutex_t *); 103 extern int mutex_owned(const kmutex_t *); 104 105 extern void *mutex_owner(const kmutex_t *); 106 107 #ifdef __cplusplus 108 } 109 #endif 110 111 #endif /* _SYS_MUTEX_H */ 112