2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1999 Eivind Eklund <eivind@FreeBSD.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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31 #ifndef _SYS_KASSERT_H_
32 #define _SYS_KASSERT_H_
34 #include <sys/cdefs.h>
37 extern const char *panicstr; /* panic message */
38 #define KERNEL_PANICKED() __predict_false(panicstr != NULL)
41 * Trap accesses going through a pointer. Moreover if kasan is available trap
42 * reading the pointer itself.
44 * Sample usage: you have a struct with numerous fields and by API contract
45 * only some of them get populated, even if the implementation temporary writes
46 * to them. You can use DEBUG_POISON_POINTER so that the consumer which should
47 * no be looking at the field gets caught.
49 * DEBUG_POISON_POINTER(obj->ptr);
51 * if (obj->ptr != NULL) // traps with kasan, does not trap otherwise
53 * if (obj->ptr->field) // traps with and without kasan
59 extern caddr_t poisoned_buf;
60 #define DEBUG_POISON_POINTER_VALUE poisoned_buf
62 #define DEBUG_POISON_POINTER(x) ({ \
63 x = (void *)(DEBUG_POISON_POINTER_VALUE); \
64 kasan_mark(&x, 0, sizeof(x), KASAN_GENERIC_REDZONE); \
68 #define DEBUG_POISON_POINTER(x)
71 #ifdef INVARIANTS /* The option is always available */
72 #define VNASSERT(exp, vp, msg) do { \
73 if (__predict_false(!(exp))) { \
74 vn_printf(vp, "VNASSERT failed: %s not true at %s:%d (%s)\n",\
75 #exp, __FILE__, __LINE__, __func__); \
79 #define MPASSERT(exp, mp, msg) do { \
80 if (__predict_false(!(exp))) { \
81 printf("MPASSERT mp %p failed: %s not true at %s:%d (%s)\n",\
82 (mp), #exp, __FILE__, __LINE__, __func__); \
86 #define VNPASS(exp, vp) do { \
87 const char *_exp = #exp; \
88 VNASSERT(exp, vp, ("condition %s not met at %s:%d (%s)", \
89 _exp, __FILE__, __LINE__, __func__)); \
91 #define MPPASS(exp, mp) do { \
92 const char *_exp = #exp; \
93 MPASSERT(exp, mp, ("condition %s not met at %s:%d (%s)", \
94 _exp, __FILE__, __LINE__, __func__)); \
96 #define __assert_unreachable() \
97 panic("executing segment marked as unreachable at %s:%d (%s)\n", \
98 __FILE__, __LINE__, __func__)
99 #else /* INVARIANTS */
100 #define VNASSERT(exp, vp, msg) do { \
102 #define MPASSERT(exp, mp, msg) do { \
104 #define VNPASS(exp, vp) do { \
106 #define MPPASS(exp, mp) do { \
108 #define __assert_unreachable() __unreachable()
109 #endif /* INVARIANTS */
111 #ifndef CTASSERT /* Allow lint to override */
112 #define CTASSERT(x) _Static_assert(x, "compile-time assertion failed")
116 * These functions need to be declared before the KASSERT macro is invoked in
117 * !KASSERT_PANIC_OPTIONAL builds, so their declarations are sort of out of
118 * place compared to other function definitions in this header. On the other
119 * hand, this header is a bit disorganized anyway.
121 void panic(const char *, ...) __dead2 __printflike(1, 2);
122 void vpanic(const char *, __va_list) __dead2 __printflike(1, 0);
125 #if defined(_STANDALONE)
127 * Until we have more experience with KASSERTS that are called
128 * from the boot loader, they are off. The bootloader does this
129 * a little differently than the kernel (we just call printf atm).
130 * we avoid most of the common functions in the boot loader, so
131 * declare printf() here too.
133 int printf(const char *, ...) __printflike(1, 2);
134 # define kassert_panic printf
135 #else /* !_STANDALONE */
136 # if defined(WITNESS) || defined(INVARIANT_SUPPORT)
137 # ifdef KASSERT_PANIC_OPTIONAL
138 void kassert_panic(const char *fmt, ...) __printflike(1, 2);
140 # define kassert_panic panic
141 # endif /* KASSERT_PANIC_OPTIONAL */
142 # endif /* defined(WITNESS) || defined(INVARIANT_SUPPORT) */
143 #endif /* _STANDALONE */
145 #if (defined(_KERNEL) && defined(INVARIANTS)) || defined(_STANDALONE)
146 #define KASSERT(exp,msg) do { \
147 if (__predict_false(!(exp))) \
150 #else /* !(KERNEL && INVARIANTS) && !_STANDALONE */
151 #define KASSERT(exp,msg) do { \
153 #endif /* (_KERNEL && INVARIANTS) || _STANDALONE */
157 * Helpful macros for quickly coming up with assertions with informative
160 #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__)
161 #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__)
162 #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line)
163 #define MPASS4(ex, what, file, line) \
164 KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line))
167 * Assert that a pointer can be loaded from memory atomically.
169 * This assertion enforces stronger alignment than necessary. For example,
170 * on some architectures, atomicity for unaligned loads will depend on
171 * whether or not the load spans multiple cache lines.
173 #define ASSERT_ATOMIC_LOAD_PTR(var, msg) \
174 KASSERT(sizeof(var) == sizeof(void *) && \
175 ((uintptr_t)&(var) & (sizeof(void *) - 1)) == 0, msg)
177 * Assert that a thread is in critical(9) section.
179 #define CRITICAL_ASSERT(td) \
180 KASSERT((td)->td_critnest >= 1, ("Not in critical section"))
184 #endif /* _SYS_KASSERT_H_ */