1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
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
31#ifndef _SYS_LOCKMGR_H_
32#define _SYS_LOCKMGR_H_
33
34#include <sys/_lock.h>
35#include <sys/_lockmgr.h>
36#include <sys/_mutex.h>
37#include <sys/_rwlock.h>
38
39#define LK_SHARE 0x01
40#define LK_SHARED_WAITERS 0x02
41#define LK_EXCLUSIVE_WAITERS 0x04
42#define LK_EXCLUSIVE_SPINNERS 0x08
43#define LK_WRITER_RECURSED 0x10
44#define LK_ALL_WAITERS \
45 (LK_SHARED_WAITERS | LK_EXCLUSIVE_WAITERS)
46#define LK_FLAGMASK \
47 (LK_SHARE | LK_ALL_WAITERS | LK_EXCLUSIVE_SPINNERS | LK_WRITER_RECURSED)
48
49#define LK_HOLDER(x) ((x) & ~LK_FLAGMASK)
50#define LK_SHARERS_SHIFT 5
51#define LK_SHARERS(x) (LK_HOLDER(x) >> LK_SHARERS_SHIFT)
52#define LK_SHARERS_LOCK(x) ((x) << LK_SHARERS_SHIFT | LK_SHARE)
53#define LK_ONE_SHARER (1 << LK_SHARERS_SHIFT)
54#define LK_UNLOCKED LK_SHARERS_LOCK(0)
55#define LK_KERNPROC ((uintptr_t)(-1) & ~LK_FLAGMASK)
56
57#ifdef _KERNEL
58
59#if !defined(LOCK_FILE) || !defined(LOCK_LINE)
60#error "LOCK_FILE and LOCK_LINE not defined, include <sys/lock.h> before"
61#endif
62
63struct thread;
64#define lk_recurse lock_object.lo_data
65
66/*
67 * Function prototipes. Routines that start with an underscore are not part
68 * of the public interface and might be wrappered with a macro.
69 */
70int __lockmgr_args(struct lock *lk, u_int flags, struct lock_object *ilk,
71 const char *wmesg, int prio, int timo, const char *file, int line);
72int lockmgr_lock_flags(struct lock *lk, u_int flags,
73 struct lock_object *ilk, const char *file, int line);
74int lockmgr_slock(struct lock *lk, u_int flags, const char *file, int line);
75int lockmgr_xlock(struct lock *lk, u_int flags, const char *file, int line);
76int lockmgr_unlock(struct lock *lk);
77
78#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
79void _lockmgr_assert(const struct lock *lk, int what, const char *file, int line);
80#endif
81void _lockmgr_disown(struct lock *lk, const char *file, int line);
82
83void lockallowrecurse(struct lock *lk);
84void lockallowshare(struct lock *lk);
85void lockdestroy(struct lock *lk);
86void lockdisablerecurse(struct lock *lk);
87void lockdisableshare(struct lock *lk);
88void lockinit(struct lock *lk, int prio, const char *wmesg, int timo,
89 int flags);
90#ifdef DDB
91int lockmgr_chain(struct thread *td, struct thread **ownerp);
92#endif
93void lockmgr_printinfo(const struct lock *lk);
94int lockstatus(const struct lock *lk);
95
96/*
97 * As far as the ilk can be a static NULL pointer these functions need a
98 * strict prototype in order to safely use the lock_object member.
99 */
100static __inline int
101_lockmgr_args(struct lock *lk, u_int flags, struct mtx *ilk, const char *wmesg,
102 int prio, int timo, const char *file, int line)
103{
104
105 return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
106 NULL, wmesg, prio, timo, file, line));
107}
108
109static __inline int
110_lockmgr_args_rw(struct lock *lk, u_int flags, struct rwlock *ilk,
111 const char *wmesg, int prio, int timo, const char *file, int line)
112{
113
114 return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
115 NULL, wmesg, prio, timo, file, line));
116}
117
118/*
119 * Define aliases in order to complete lockmgr KPI.
120 */
121#define lockmgr_read_value(lk) ((lk)->lk_lock)
122#define lockmgr(lk, flags, ilk) \
123 _lockmgr_args((lk), (flags), (ilk), LK_WMESG_DEFAULT, \
124 LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
125#define lockmgr_args(lk, flags, ilk, wmesg, prio, timo) \
126 _lockmgr_args((lk), (flags), (ilk), (wmesg), (prio), (timo), \
127 LOCK_FILE, LOCK_LINE)
128#define lockmgr_args_rw(lk, flags, ilk, wmesg, prio, timo) \
129 _lockmgr_args_rw((lk), (flags), (ilk), (wmesg), (prio), (timo), \
130 LOCK_FILE, LOCK_LINE)
131#define lockmgr_disown(lk) \
132 _lockmgr_disown((lk), LOCK_FILE, LOCK_LINE)
133#define lockmgr_disowned_v(v) \
134 (LK_HOLDER((v)) == LK_KERNPROC)
135#define lockmgr_disowned(lk) \
136 lockmgr_disowned_v(lockmgr_read_value((lk)))
137#define lockmgr_recursed_v(v) \
138 (v & LK_WRITER_RECURSED)
139#define lockmgr_recursed(lk) \
140 lockmgr_recursed_v((lk)->lk_lock)
141#define lockmgr_rw(lk, flags, ilk) \
142 _lockmgr_args_rw((lk), (flags), (ilk), LK_WMESG_DEFAULT, \
143 LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
144#ifdef INVARIANTS
145#define lockmgr_assert(lk, what) \
146 _lockmgr_assert((lk), (what), LOCK_FILE, LOCK_LINE)
147#else
148#define lockmgr_assert(lk, what)
149#endif
150
151/*
152 * Flags for lockinit().
153 */
154#define LK_INIT_MASK 0x0001FF
155#define LK_CANRECURSE 0x000001
156#define LK_NODUP 0x000002
157#define LK_NOPROFILE 0x000004
158#define LK_NOSHARE 0x000008
159#define LK_NOWITNESS 0x000010
160#define LK_QUIET 0x000020
161#define LK_UNUSED0 0x000040 /* Was LK_ADAPTIVE */
162#define LK_IS_VNODE 0x000080 /* Tell WITNESS about a VNODE lock */
163#define LK_NEW 0x000100
164
165/*
166 * Additional attributes to be used in lockmgr().
167 */
168#define LK_EATTR_MASK 0x00FF00
169#define LK_INTERLOCK 0x000100
170#define LK_NOWAIT 0x000200
171#define LK_RETRY 0x000400
172#define LK_SLEEPFAIL 0x000800
173#define LK_TIMELOCK 0x001000
174#define LK_NODDLKTREAT 0x002000
175#define LK_ADAPTIVE 0x004000
176
177/*
178 * Operations for lockmgr().
179 */
180#define LK_TYPE_MASK 0xFF0000
181#define LK_DOWNGRADE 0x010000
182#define LK_DRAIN 0x020000
183#define LK_EXCLOTHER 0x040000
184#define LK_EXCLUSIVE 0x080000
185#define LK_RELEASE 0x100000
186#define LK_SHARED 0x200000
187#define LK_UPGRADE 0x400000
188#define LK_TRYUPGRADE 0x800000
189
190#define LK_TOTAL_MASK (LK_INIT_MASK | LK_EATTR_MASK | LK_TYPE_MASK)
191
192/*
193 * Default values for lockmgr_args().
194 */
195#define LK_WMESG_DEFAULT (NULL)
196#define LK_PRIO_DEFAULT (0)
197#define LK_TIMO_DEFAULT (0)
198
199/*
200 * Assertion flags.
201 */
202#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
203#define KA_LOCKED LA_LOCKED
204#define KA_SLOCKED LA_SLOCKED
205#define KA_XLOCKED LA_XLOCKED
206#define KA_UNLOCKED LA_UNLOCKED
207#define KA_RECURSED LA_RECURSED
208#define KA_NOTRECURSED LA_NOTRECURSED
209#endif
210
211#endif /* _KERNEL */
212
213#endif /* !_SYS_LOCKMGR_H_ */