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