/*-
 * Copyright (c) 2021 The FreeBSD Foundation
 *
 * This software were developed by Konstantin Belousov <kib@FreeBSD.org>
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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, 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 __SYS_MEMBARRIER_H__
#define __SYS_MEMBARRIER_H__

#include <sys/cdefs.h>

/*
 * The enum membarrier_cmd values are bits.  The MEMBARRIER_CMD_QUERY
 * command returns a bitset indicating which commands are supported.
 * Also the value of MEMBARRIER_CMD_QUERY is zero, so it is
 * effectively not returned by the query.
 */
enum membarrier_cmd {
        MEMBARRIER_CMD_QUERY =                          0x00000000,
        MEMBARRIER_CMD_GLOBAL =                         0x00000001,
        MEMBARRIER_CMD_SHARED =                         MEMBARRIER_CMD_GLOBAL,
        MEMBARRIER_CMD_GLOBAL_EXPEDITED =               0x00000002,
        MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED =      0x00000004,
        MEMBARRIER_CMD_PRIVATE_EXPEDITED =              0x00000008,
        MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED =     0x00000010,
        MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE =    0x00000020,
        MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE =   0x00000040,

        /*
         * RSEQ constants are defined for source compatibility but are
         * not yet supported, MEMBARRIER_CMD_QUERY does not return
         * them in the mask.
         */
        MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ =         0x00000080,
        MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_RSEQ = 0x00000100,

        /* Return the bitmask of current registrations. */
        MEMBARRIER_CMD_GET_REGISTRATIONS =              0x00000200,
};

enum membarrier_cmd_flag {
        MEMBARRIER_CMD_FLAG_CPU =                       0x00000001,
};

#ifndef _KERNEL
__BEGIN_DECLS
int membarrier(int, unsigned, int);
__END_DECLS
#endif  /* _KERNEL */

#endif /* __SYS_MEMBARRIER_H__ */