/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2008 Attilio Rao <attilio@FreeBSD.org>
 * 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(s), this list of conditions and the following disclaimer as
 *    the first lines of this file unmodified other than the possible 
 *    addition of one or more copyright notices.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice(s), 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 COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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_LOCKMGR_H_
#define _SYS_LOCKMGR_H_

#include <sys/_lock.h>
#include <sys/_lockmgr.h>
#include <sys/_mutex.h>
#include <sys/_rwlock.h>

#define LK_SHARE                        0x01
#define LK_SHARED_WAITERS               0x02
#define LK_EXCLUSIVE_WAITERS            0x04
#define LK_EXCLUSIVE_SPINNERS           0x08
#define LK_WRITER_RECURSED              0x10
#define LK_ALL_WAITERS                                                  \
        (LK_SHARED_WAITERS | LK_EXCLUSIVE_WAITERS)
#define LK_FLAGMASK                                                     \
        (LK_SHARE | LK_ALL_WAITERS | LK_EXCLUSIVE_SPINNERS | LK_WRITER_RECURSED)

#define LK_HOLDER(x)                    ((x) & ~LK_FLAGMASK)
#define LK_SHARERS_SHIFT                5
#define LK_SHARERS(x)                   (LK_HOLDER(x) >> LK_SHARERS_SHIFT)
#define LK_SHARERS_LOCK(x)              ((x) << LK_SHARERS_SHIFT | LK_SHARE)
#define LK_ONE_SHARER                   (1 << LK_SHARERS_SHIFT)
#define LK_UNLOCKED                     LK_SHARERS_LOCK(0)
#define LK_KERNPROC                     ((uintptr_t)(-1) & ~LK_FLAGMASK)

#ifdef _KERNEL

#if !defined(LOCK_FILE) || !defined(LOCK_LINE)
#error  "LOCK_FILE and LOCK_LINE not defined, include <sys/lock.h> before"
#endif

struct thread;
#define lk_recurse      lock_object.lo_data

/*
 * Function prototipes.  Routines that start with an underscore are not part
 * of the public interface and might be wrappered with a macro.
 */
int      __lockmgr_args(struct lock *lk, u_int flags, struct lock_object *ilk,
            const char *wmesg, int prio, int timo, const char *file, int line);
int      lockmgr_lock_flags(struct lock *lk, u_int flags,
            struct lock_object *ilk, const char *file, int line);
int     lockmgr_slock(struct lock *lk, u_int flags, const char *file, int line);
int     lockmgr_xlock(struct lock *lk, u_int flags, const char *file, int line);
int     lockmgr_unlock(struct lock *lk);

#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
void     _lockmgr_assert(const struct lock *lk, int what, const char *file, int line);
#endif
void     _lockmgr_disown(struct lock *lk, const char *file, int line);

void     lockallowrecurse(struct lock *lk);
void     lockallowshare(struct lock *lk);
void     lockdestroy(struct lock *lk);
void     lockdisablerecurse(struct lock *lk);
void     lockdisableshare(struct lock *lk);
void     lockinit(struct lock *lk, int prio, const char *wmesg, int timo,
            int flags);
#ifdef DDB
int      lockmgr_chain(struct thread *td, struct thread **ownerp);
#endif
void     lockmgr_printinfo(const struct lock *lk);
int      lockstatus(const struct lock *lk);

/*
 * As far as the ilk can be a static NULL pointer these functions need a
 * strict prototype in order to safely use the lock_object member.
 */
static __inline int
_lockmgr_args(struct lock *lk, u_int flags, struct mtx *ilk, const char *wmesg,
    int prio, int timo, const char *file, int line)
{

        return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
            NULL, wmesg, prio, timo, file, line));
}

static __inline int
_lockmgr_args_rw(struct lock *lk, u_int flags, struct rwlock *ilk,
    const char *wmesg, int prio, int timo, const char *file, int line)
{

        return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
            NULL, wmesg, prio, timo, file, line));
}

/*
 * Define aliases in order to complete lockmgr KPI.
 */
#define lockmgr_read_value(lk)  ((lk)->lk_lock)
#define lockmgr(lk, flags, ilk)                                         \
        _lockmgr_args((lk), (flags), (ilk), LK_WMESG_DEFAULT,           \
            LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
#define lockmgr_args(lk, flags, ilk, wmesg, prio, timo)                 \
        _lockmgr_args((lk), (flags), (ilk), (wmesg), (prio), (timo),    \
            LOCK_FILE, LOCK_LINE)
#define lockmgr_args_rw(lk, flags, ilk, wmesg, prio, timo)              \
        _lockmgr_args_rw((lk), (flags), (ilk), (wmesg), (prio), (timo), \
            LOCK_FILE, LOCK_LINE)
#define lockmgr_disown(lk)                                              \
        _lockmgr_disown((lk), LOCK_FILE, LOCK_LINE)
#define lockmgr_disowned_v(v)                                           \
        (LK_HOLDER((v)) == LK_KERNPROC)
#define lockmgr_disowned(lk)                                            \
        lockmgr_disowned_v(lockmgr_read_value((lk)))
#define lockmgr_recursed_v(v)                                           \
        (v & LK_WRITER_RECURSED)
#define lockmgr_recursed(lk)                                            \
        lockmgr_recursed_v((lk)->lk_lock)
#define lockmgr_rw(lk, flags, ilk)                                      \
        _lockmgr_args_rw((lk), (flags), (ilk), LK_WMESG_DEFAULT,        \
            LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
#ifdef INVARIANTS
#define lockmgr_assert(lk, what)                                        \
        _lockmgr_assert((lk), (what), LOCK_FILE, LOCK_LINE)
#else
#define lockmgr_assert(lk, what)
#endif

/*
 * Flags for lockinit().
 */
#define LK_INIT_MASK    0x0001FF
#define LK_CANRECURSE   0x000001
#define LK_NODUP        0x000002
#define LK_NOPROFILE    0x000004
#define LK_NOSHARE      0x000008
#define LK_NOWITNESS    0x000010
#define LK_QUIET        0x000020
#define LK_UNUSED0      0x000040        /* Was LK_ADAPTIVE */
#define LK_IS_VNODE     0x000080        /* Tell WITNESS about a VNODE lock */
#define LK_NEW          0x000100

/*
 * Additional attributes to be used in lockmgr().
 */
#define LK_EATTR_MASK   0x00FF00
#define LK_INTERLOCK    0x000100
#define LK_NOWAIT       0x000200
#define LK_RETRY        0x000400
#define LK_SLEEPFAIL    0x000800
#define LK_TIMELOCK     0x001000
#define LK_NODDLKTREAT  0x002000
#define LK_ADAPTIVE     0x004000

/*
 * Operations for lockmgr().
 */
#define LK_TYPE_MASK    0xFF0000
#define LK_DOWNGRADE    0x010000
#define LK_DRAIN        0x020000
#define LK_EXCLOTHER    0x040000
#define LK_EXCLUSIVE    0x080000
#define LK_RELEASE      0x100000
#define LK_SHARED       0x200000
#define LK_UPGRADE      0x400000
#define LK_TRYUPGRADE   0x800000

#define LK_TOTAL_MASK   (LK_INIT_MASK | LK_EATTR_MASK | LK_TYPE_MASK)

/*
 * Default values for lockmgr_args().
 */
#define LK_WMESG_DEFAULT        (NULL)
#define LK_PRIO_DEFAULT         (0)
#define LK_TIMO_DEFAULT         (0)

/*
 * Assertion flags.
 */
#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
#define KA_LOCKED       LA_LOCKED
#define KA_SLOCKED      LA_SLOCKED
#define KA_XLOCKED      LA_XLOCKED
#define KA_UNLOCKED     LA_UNLOCKED
#define KA_RECURSED     LA_RECURSED
#define KA_NOTRECURSED  LA_NOTRECURSED
#endif

#endif /* _KERNEL */

#endif /* !_SYS_LOCKMGR_H_ */