1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2008 Attilio Rao <attilio@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice(s), this list of conditions and the following disclaimer as
12 *    the first lines of this file unmodified other than the possible
13 *    addition of one or more copyright notices.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice(s), this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
19 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
28 * DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33#ifndef	_SYS_LOCKMGR_H_
34#define	_SYS_LOCKMGR_H_
35
36#include <sys/_lock.h>
37#include <sys/_lockmgr.h>
38#include <sys/_mutex.h>
39#include <sys/_rwlock.h>
40
41#define	LK_SHARE			0x01
42#define	LK_SHARED_WAITERS		0x02
43#define	LK_EXCLUSIVE_WAITERS		0x04
44#define	LK_EXCLUSIVE_SPINNERS		0x08
45#define	LK_ALL_WAITERS							\
46	(LK_SHARED_WAITERS | LK_EXCLUSIVE_WAITERS)
47#define	LK_FLAGMASK							\
48	(LK_SHARE | LK_ALL_WAITERS | LK_EXCLUSIVE_SPINNERS)
49
50#define	LK_HOLDER(x)			((x) & ~LK_FLAGMASK)
51#define	LK_SHARERS_SHIFT		4
52#define	LK_SHARERS(x)			(LK_HOLDER(x) >> LK_SHARERS_SHIFT)
53#define	LK_SHARERS_LOCK(x)		((x) << LK_SHARERS_SHIFT | LK_SHARE)
54#define	LK_ONE_SHARER			(1 << LK_SHARERS_SHIFT)
55#define	LK_UNLOCKED			LK_SHARERS_LOCK(0)
56#define	LK_KERNPROC			((uintptr_t)(-1) & ~LK_FLAGMASK)
57
58#ifdef _KERNEL
59
60#if !defined(LOCK_FILE) || !defined(LOCK_LINE)
61#error	"LOCK_FILE and LOCK_LINE not defined, include <sys/lock.h> before"
62#endif
63
64struct thread;
65#define	lk_recurse	lock_object.lo_data
66
67/*
68 * Function prototipes.  Routines that start with an underscore are not part
69 * of the public interface and might be wrappered with a macro.
70 */
71int	 __lockmgr_args(struct lock *lk, u_int flags, struct lock_object *ilk,
72	    const char *wmesg, int prio, int timo, const char *file, int line);
73int	 lockmgr_lock_fast_path(struct lock *lk, u_int flags,
74	    struct lock_object *ilk, const char *file, int line);
75int	 lockmgr_unlock_fast_path(struct lock *lk, u_int flags,
76	    struct lock_object *ilk);
77#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
78void	 _lockmgr_assert(const struct lock *lk, int what, const char *file, int line);
79#endif
80void	 _lockmgr_disown(struct lock *lk, const char *file, int line);
81
82void	 lockallowrecurse(struct lock *lk);
83void	 lockallowshare(struct lock *lk);
84void	 lockdestroy(struct lock *lk);
85void	 lockdisablerecurse(struct lock *lk);
86void	 lockdisableshare(struct lock *lk);
87void	 lockinit(struct lock *lk, int prio, const char *wmesg, int timo,
88	    int flags);
89#ifdef DDB
90int	 lockmgr_chain(struct thread *td, struct thread **ownerp);
91#endif
92void	 lockmgr_printinfo(const struct lock *lk);
93int	 lockstatus(const struct lock *lk);
94
95/*
96 * As far as the ilk can be a static NULL pointer these functions need a
97 * strict prototype in order to safely use the lock_object member.
98 */
99static __inline int
100_lockmgr_args(struct lock *lk, u_int flags, struct mtx *ilk, const char *wmesg,
101    int prio, int timo, const char *file, int line)
102{
103
104	return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
105	    NULL, wmesg, prio, timo, file, line));
106}
107
108static __inline int
109_lockmgr_args_rw(struct lock *lk, u_int flags, struct rwlock *ilk,
110    const char *wmesg, int prio, int timo, const char *file, int line)
111{
112
113	return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
114	    NULL, wmesg, prio, timo, file, line));
115}
116
117/*
118 * Define aliases in order to complete lockmgr KPI.
119 */
120#define	lockmgr(lk, flags, ilk)						\
121	_lockmgr_args((lk), (flags), (ilk), LK_WMESG_DEFAULT,		\
122	    LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
123#define	lockmgr_args(lk, flags, ilk, wmesg, prio, timo)			\
124	_lockmgr_args((lk), (flags), (ilk), (wmesg), (prio), (timo),	\
125	    LOCK_FILE, LOCK_LINE)
126#define	lockmgr_args_rw(lk, flags, ilk, wmesg, prio, timo)		\
127	_lockmgr_args_rw((lk), (flags), (ilk), (wmesg), (prio), (timo),	\
128	    LOCK_FILE, LOCK_LINE)
129#define	lockmgr_disown(lk)						\
130	_lockmgr_disown((lk), LOCK_FILE, LOCK_LINE)
131#define	lockmgr_recursed(lk)						\
132	((lk)->lk_recurse != 0)
133#define	lockmgr_rw(lk, flags, ilk)					\
134	_lockmgr_args_rw((lk), (flags), (ilk), LK_WMESG_DEFAULT,	\
135	    LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
136#ifdef INVARIANTS
137#define	lockmgr_assert(lk, what)					\
138	_lockmgr_assert((lk), (what), LOCK_FILE, LOCK_LINE)
139#else
140#define	lockmgr_assert(lk, what)
141#endif
142
143/*
144 * Flags for lockinit().
145 */
146#define	LK_INIT_MASK	0x0000FF
147#define	LK_CANRECURSE	0x000001
148#define	LK_NODUP	0x000002
149#define	LK_NOPROFILE	0x000004
150#define	LK_NOSHARE	0x000008
151#define	LK_NOWITNESS	0x000010
152#define	LK_QUIET	0x000020
153#define	LK_ADAPTIVE	0x000040
154#define	LK_IS_VNODE	0x000080	/* Tell WITNESS about a VNODE lock */
155
156/*
157 * Additional attributes to be used in lockmgr().
158 */
159#define	LK_EATTR_MASK	0x00FF00
160#define	LK_INTERLOCK	0x000100
161#define	LK_NOWAIT	0x000200
162#define	LK_RETRY	0x000400
163#define	LK_SLEEPFAIL	0x000800
164#define	LK_TIMELOCK	0x001000
165#define	LK_NODDLKTREAT	0x002000
166#define	LK_VNHELD	0x004000
167
168/*
169 * Operations for lockmgr().
170 */
171#define	LK_TYPE_MASK	0xFF0000
172#define	LK_DOWNGRADE	0x010000
173#define	LK_DRAIN	0x020000
174#define	LK_EXCLOTHER	0x040000
175#define	LK_EXCLUSIVE	0x080000
176#define	LK_RELEASE	0x100000
177#define	LK_SHARED	0x200000
178#define	LK_UPGRADE	0x400000
179#define	LK_TRYUPGRADE	0x800000
180
181#define	LK_TOTAL_MASK	(LK_INIT_MASK | LK_EATTR_MASK | LK_TYPE_MASK)
182
183/*
184 * Default values for lockmgr_args().
185 */
186#define	LK_WMESG_DEFAULT	(NULL)
187#define	LK_PRIO_DEFAULT		(0)
188#define	LK_TIMO_DEFAULT		(0)
189
190/*
191 * Assertion flags.
192 */
193#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
194#define	KA_LOCKED	LA_LOCKED
195#define	KA_SLOCKED	LA_SLOCKED
196#define	KA_XLOCKED	LA_XLOCKED
197#define	KA_UNLOCKED	LA_UNLOCKED
198#define	KA_RECURSED	LA_RECURSED
199#define	KA_NOTRECURSED	LA_NOTRECURSED
200#endif
201
202#endif /* _KERNEL */
203
204#endif /* !_SYS_LOCKMGR_H_ */
205