diff options
Diffstat (limited to 'sys/compat/linuxkpi/common/include/linux/rwsem.h')
| -rw-r--r-- | sys/compat/linuxkpi/common/include/linux/rwsem.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/sys/compat/linuxkpi/common/include/linux/rwsem.h b/sys/compat/linuxkpi/common/include/linux/rwsem.h new file mode 100644 index 000000000000..b7a800b12e18 --- /dev/null +++ b/sys/compat/linuxkpi/common/include/linux/rwsem.h @@ -0,0 +1,85 @@ +/*- + * Copyright (c) 2010 Isilon Systems, Inc. + * Copyright (c) 2010 iX Systems, Inc. + * Copyright (c) 2010 Panasas, Inc. + * Copyright (c) 2013-2017 Mellanox Technologies, Ltd. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef _LINUXKPI_LINUX_RWSEM_H_ +#define _LINUXKPI_LINUX_RWSEM_H_ + +#include <sys/param.h> +#include <sys/lock.h> +#include <sys/sx.h> +#include <sys/libkern.h> +#include <sys/kernel.h> + +struct rw_semaphore { + struct sx sx; +}; + +#define down_write(_rw) sx_xlock(&(_rw)->sx) +#define up_write(_rw) sx_xunlock(&(_rw)->sx) +#define down_read(_rw) sx_slock(&(_rw)->sx) +#define up_read(_rw) sx_sunlock(&(_rw)->sx) +#define down_read_trylock(_rw) !!sx_try_slock(&(_rw)->sx) +#define down_read_killable(_rw) linux_down_read_killable(_rw) +#define down_write_trylock(_rw) !!sx_try_xlock(&(_rw)->sx) +#define down_write_killable(_rw) linux_down_write_killable(_rw) +#define downgrade_write(_rw) sx_downgrade(&(_rw)->sx) +#define down_read_nested(_rw, _sc) down_read(_rw) +#define init_rwsem(_rw) linux_init_rwsem(_rw, rwsem_name("lnxrwsem")) +#define down_write_nest_lock(sem, _rw) down_write(_rw) + +#ifdef WITNESS_ALL +/* NOTE: the maximum WITNESS name is 64 chars */ +#define __rwsem_name(name, file, line) \ + (((const char *){file ":" #line "-" name}) + \ + (sizeof(file) > 16 ? sizeof(file) - 16 : 0)) +#else +#define __rwsem_name(name, file, line) name +#endif +#define _rwsem_name(...) __rwsem_name(__VA_ARGS__) +#define rwsem_name(name) _rwsem_name(name, __FILE__, __LINE__) + +#define DECLARE_RWSEM(name) \ +struct rw_semaphore name; \ +static void name##_rwsem_init(void *arg) \ +{ \ + linux_init_rwsem(&name, rwsem_name(#name)); \ +} \ +SYSINIT(name, SI_SUB_LOCK, SI_ORDER_SECOND, name##_rwsem_init, NULL) + +static inline void +linux_init_rwsem(struct rw_semaphore *rw, const char *name) +{ + + memset(rw, 0, sizeof(*rw)); + sx_init_flags(&rw->sx, name, SX_NOWITNESS); +} + +extern int linux_down_read_killable(struct rw_semaphore *); +extern int linux_down_write_killable(struct rw_semaphore *); + +#endif /* _LINUXKPI_LINUX_RWSEM_H_ */ |