1219820Sjeff/*- 2219820Sjeff * Copyright (c) 2010 Isilon Systems, Inc. 3219820Sjeff * Copyright (c) 2010 iX Systems, Inc. 4219820Sjeff * Copyright (c) 2010 Panasas, Inc. 5219820Sjeff * All rights reserved. 6219820Sjeff * 7219820Sjeff * Redistribution and use in source and binary forms, with or without 8219820Sjeff * modification, are permitted provided that the following conditions 9219820Sjeff * are met: 10219820Sjeff * 1. Redistributions of source code must retain the above copyright 11219820Sjeff * notice unmodified, this list of conditions, and the following 12219820Sjeff * disclaimer. 13219820Sjeff * 2. Redistributions in binary form must reproduce the above copyright 14219820Sjeff * notice, this list of conditions and the following disclaimer in the 15219820Sjeff * documentation and/or other materials provided with the distribution. 16219820Sjeff * 17219820Sjeff * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18219820Sjeff * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19219820Sjeff * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20219820Sjeff * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21219820Sjeff * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22219820Sjeff * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23219820Sjeff * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24219820Sjeff * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25219820Sjeff * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26219820Sjeff * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27219820Sjeff */ 28219820Sjeff#ifndef _LINUX_RWSEM_H_ 29219820Sjeff#define _LINUX_RWSEM_H_ 30219820Sjeff 31219820Sjeff#include <sys/param.h> 32219820Sjeff#include <sys/lock.h> 33219820Sjeff#include <sys/sx.h> 34219820Sjeff 35219820Sjeffstruct rw_semaphore { 36219820Sjeff struct sx sx; 37219820Sjeff}; 38219820Sjeff 39219820Sjeff#define down_write(_rw) sx_xlock(&(_rw)->sx) 40219820Sjeff#define up_write(_rw) sx_xunlock(&(_rw)->sx) 41219820Sjeff#define down_read(_rw) sx_slock(&(_rw)->sx) 42219820Sjeff#define up_read(_rw) sx_sunlock(&(_rw)->sx) 43219820Sjeff#define down_read_trylock(_rw) !!sx_try_slock(&(_rw)->sx) 44219820Sjeff#define down_write_trylock(_rw) !!sx_try_xlock(&(_rw)->sx) 45219820Sjeff#define downgrade_write(_rw) sx_downgrade(&(_rw)->sx) 46219820Sjeff#define down_read_nested(_rw, _sc) down_read(_rw) 47219820Sjeff 48219820Sjeffstatic inline void 49219820Sjeffinit_rwsem(struct rw_semaphore *rw) 50219820Sjeff{ 51219820Sjeff 52219820Sjeff memset(&rw->sx, 0, sizeof(rw->sx)); 53219820Sjeff sx_init_flags(&rw->sx, "lnxrwsem", SX_NOWITNESS); 54219820Sjeff} 55219820Sjeff 56219820Sjeff#endif /* _LINUX_RWSEM_H_ */ 57