/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (C) 2017 Jorgen Lundman <lundman@lundman.net>
 */

#ifndef _SPL_RWLOCK_H
#define _SPL_RWLOCK_H

#include <sys/types.h>
//#include <kern/locks.h>

typedef enum {
        RW_DRIVER  = 2,
        RW_DEFAULT = 4
} krw_type_t;

typedef enum {
        RW_NONE   = 0,
        RW_WRITER = 1,
        RW_READER = 2
} krw_t;

struct krwlock {
	ERESOURCE	rw_lock; /* opaque data */
    void       *rw_owner;    /* writer (exclusive) lock only */
    int        rw_readers;   /* reader lock only */
    int        rw_pad;       /* */
};
typedef struct krwlock  krwlock_t;

#define RW_WRITE_HELD(x)        (rw_write_held((x)))
#define RW_LOCK_HELD(x)         (rw_lock_held((x)))

extern  void  rw_init(krwlock_t *, char *, krw_type_t, void *);
extern  void  rw_destroy(krwlock_t *);
extern  void  rw_enter(krwlock_t *, krw_t);
extern  int   rw_tryenter(krwlock_t *, krw_t);
extern  void  rw_exit(krwlock_t *);
extern  void  rw_downgrade(krwlock_t *);
extern  int   rw_tryupgrade(krwlock_t *);
extern  int   rw_write_held(krwlock_t *);
extern  int   rw_lock_held(krwlock_t *);
extern  int   rw_isinit(krwlock_t *);

int  spl_rwlock_init(void);
void spl_rwlock_fini(void);

#endif /* _SPL_RWLOCK_H */
