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
63 struct 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 */
70 int __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);
72 int lockmgr_lock_flags(struct lock *lk, u_int flags,
73 struct lock_object *ilk, const char *file, int line);
74 int lockmgr_slock(struct lock *lk, u_int flags, const char *file, int line);
75 int lockmgr_xlock(struct lock *lk, u_int flags, const char *file, int line);
76 int lockmgr_unlock(struct lock *lk);
77
78 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
79 void _lockmgr_assert(const struct lock *lk, int what, const char *file, int line);
80 #endif
81 void _lockmgr_disown(struct lock *lk, const char *file, int line);
82
83 void lockallowrecurse(struct lock *lk);
84 void lockallowshare(struct lock *lk);
85 bool lockcanrecurse(struct lock *lk);
86 void lockdestroy(struct lock *lk);
87 void lockdisablerecurse(struct lock *lk);
88 void lockdisableshare(struct lock *lk);
89 void lockinit(struct lock *lk, int prio, const char *wmesg, int timo,
90 int flags);
91 #ifdef DDB
92 int lockmgr_chain(struct thread *td, struct thread **ownerp);
93 #endif
94 void lockmgr_printinfo(const struct lock *lk);
95 int lockstatus(const struct lock *lk);
96
97 /*
98 * As far as the ilk can be a static NULL pointer these functions need a
99 * strict prototype in order to safely use the lock_object member.
100 */
101 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)102 _lockmgr_args(struct lock *lk, u_int flags, struct mtx *ilk, const char *wmesg,
103 int prio, int timo, const char *file, int line)
104 {
105
106 return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
107 NULL, wmesg, prio, timo, file, line));
108 }
109
110 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)111 _lockmgr_args_rw(struct lock *lk, u_int flags, struct rwlock *ilk,
112 const char *wmesg, int prio, int timo, const char *file, int line)
113 {
114
115 return (__lockmgr_args(lk, flags, (ilk != NULL) ? &ilk->lock_object :
116 NULL, wmesg, prio, timo, file, line));
117 }
118
119 /*
120 * Define aliases in order to complete lockmgr KPI.
121 */
122 #define lockmgr_read_value(lk) ((lk)->lk_lock)
123 #define lockmgr(lk, flags, ilk) \
124 _lockmgr_args((lk), (flags), (ilk), LK_WMESG_DEFAULT, \
125 LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
126 #define lockmgr_args(lk, flags, ilk, wmesg, prio, timo) \
127 _lockmgr_args((lk), (flags), (ilk), (wmesg), (prio), (timo), \
128 LOCK_FILE, LOCK_LINE)
129 #define lockmgr_args_rw(lk, flags, ilk, wmesg, prio, timo) \
130 _lockmgr_args_rw((lk), (flags), (ilk), (wmesg), (prio), (timo), \
131 LOCK_FILE, LOCK_LINE)
132 #define lockmgr_disown(lk) \
133 _lockmgr_disown((lk), LOCK_FILE, LOCK_LINE)
134 #define lockmgr_disowned_v(v) \
135 (LK_HOLDER((v)) == LK_KERNPROC)
136 #define lockmgr_disowned(lk) \
137 lockmgr_disowned_v(lockmgr_read_value((lk)))
138 #define lockmgr_recursed_v(v) \
139 (v & LK_WRITER_RECURSED)
140 #define lockmgr_recursed(lk) \
141 lockmgr_recursed_v((lk)->lk_lock)
142 #define lockmgr_rw(lk, flags, ilk) \
143 _lockmgr_args_rw((lk), (flags), (ilk), LK_WMESG_DEFAULT, \
144 LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)
145 #ifdef INVARIANTS
146 #define lockmgr_assert(lk, what) \
147 _lockmgr_assert((lk), (what), LOCK_FILE, LOCK_LINE)
148 #else
149 #define lockmgr_assert(lk, what)
150 #endif
151
152 /*
153 * Flags for lockinit().
154 */
155 #define LK_INIT_MASK 0x0001FF
156 #define LK_CANRECURSE 0x000001
157 #define LK_NODUP 0x000002
158 #define LK_NOPROFILE 0x000004
159 #define LK_NOSHARE 0x000008
160 #define LK_NOWITNESS 0x000010
161 #define LK_QUIET 0x000020
162 #define LK_UNUSED0 0x000040 /* Was LK_ADAPTIVE */
163 #define LK_IS_VNODE 0x000080 /* Tell WITNESS about a VNODE lock */
164 #define LK_NEW 0x000100
165
166 /*
167 * Additional attributes to be used in lockmgr().
168 */
169 #define LK_EATTR_MASK 0x00FF00
170 #define LK_INTERLOCK 0x000100
171 #define LK_NOWAIT 0x000200
172 #define LK_RETRY 0x000400
173 #define LK_SLEEPFAIL 0x000800
174 #define LK_TIMELOCK 0x001000
175 #define LK_NODDLKTREAT 0x002000
176 #define LK_ADAPTIVE 0x004000
177
178 /*
179 * Operations for lockmgr().
180 */
181 #define LK_TYPE_MASK 0xFF0000
182 #define LK_DOWNGRADE 0x010000
183 #define LK_DRAIN 0x020000
184 #define LK_EXCLOTHER 0x040000
185 #define LK_EXCLUSIVE 0x080000
186 #define LK_RELEASE 0x100000
187 #define LK_SHARED 0x200000
188 #define LK_UPGRADE 0x400000
189 #define LK_TRYUPGRADE 0x800000
190
191 #define LK_TOTAL_MASK (LK_INIT_MASK | LK_EATTR_MASK | LK_TYPE_MASK)
192
193 /*
194 * Default values for lockmgr_args().
195 */
196 #define LK_WMESG_DEFAULT (NULL)
197 #define LK_PRIO_DEFAULT (0)
198 #define LK_TIMO_DEFAULT (0)
199
200 /*
201 * Assertion flags.
202 */
203 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
204 #define KA_LOCKED LA_LOCKED
205 #define KA_SLOCKED LA_SLOCKED
206 #define KA_XLOCKED LA_XLOCKED
207 #define KA_UNLOCKED LA_UNLOCKED
208 #define KA_RECURSED LA_RECURSED
209 #define KA_NOTRECURSED LA_NOTRECURSED
210 #endif
211
212 #endif /* _KERNEL */
213
214 #endif /* !_SYS_LOCKMGR_H_ */
215