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 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 28 */ 29 30 #ifndef _SYS_RWLOCK_H 31 #define _SYS_RWLOCK_H 32 33 /* 34 * Public interface to readers/writer locks. See rwlock(9F) for details. 35 */ 36 37 #include <sys/types.h> 38 39 #ifdef __cplusplus 40 extern "C" { 41 #endif 42 43 #ifndef _ASM 44 45 typedef enum { 46 RW_DRIVER = 2, /* driver (DDI) rwlock */ 47 RW_DEFAULT = 4 /* kernel default rwlock */ 48 } krw_type_t; 49 50 typedef enum { 51 RW_WRITER, 52 RW_READER, 53 RW_READER_STARVEWRITER 54 } krw_t; 55 56 typedef struct _krwlock { 57 void *_opaque[1]; 58 } krwlock_t; 59 60 #if defined(_KERNEL) 61 62 #define RW_READ_HELD(x) (rw_read_held((x))) 63 #define RW_WRITE_HELD(x) (rw_write_held((x))) 64 #define RW_LOCK_HELD(x) (rw_lock_held((x))) 65 #define RW_ISWRITER(x) (rw_iswriter(x)) 66 67 extern void rw_init(krwlock_t *, char *, krw_type_t, void *); 68 extern void rw_destroy(krwlock_t *); 69 extern void rw_enter(krwlock_t *, krw_t); 70 extern int rw_tryenter(krwlock_t *, krw_t); 71 extern void rw_exit(krwlock_t *); 72 extern void rw_downgrade(krwlock_t *); 73 extern int rw_tryupgrade(krwlock_t *); 74 extern int rw_read_held(krwlock_t *); 75 extern int rw_write_held(krwlock_t *); 76 extern int rw_lock_held(krwlock_t *); 77 extern int rw_read_locked(krwlock_t *); 78 extern int rw_iswriter(krwlock_t *); 79 extern struct _kthread *rw_owner(krwlock_t *); 80 extern uint_t (*rw_lock_backoff)(uint_t); 81 extern void (*rw_lock_delay)(uint_t); 82 83 #endif /* defined(_KERNEL) */ 84 85 #endif /* _ASM */ 86 87 #ifdef __cplusplus 88 } 89 #endif 90 91 #endif /* _SYS_RWLOCK_H */ 92