Merge branch 'setns'
[linux-2.6.git] / include / asm-generic / bug.h
1 #ifndef _ASM_GENERIC_BUG_H
2 #define _ASM_GENERIC_BUG_H
3
4 #include <linux/compiler.h>
5
6 #ifdef CONFIG_BUG
7
8 #ifdef CONFIG_GENERIC_BUG
9 #ifndef __ASSEMBLY__
10 struct bug_entry {
11 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
12         unsigned long   bug_addr;
13 #else
14         signed int      bug_addr_disp;
15 #endif
16 #ifdef CONFIG_DEBUG_BUGVERBOSE
17 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
18         const char      *file;
19 #else
20         signed int      file_disp;
21 #endif
22         unsigned short  line;
23 #endif
24         unsigned short  flags;
25 };
26 #endif          /* __ASSEMBLY__ */
27
28 #define BUGFLAG_WARNING         (1 << 0)
29 #define BUGFLAG_TAINT(taint)    (BUGFLAG_WARNING | ((taint) << 8))
30 #define BUG_GET_TAINT(bug)      ((bug)->flags >> 8)
31
32 #endif  /* CONFIG_GENERIC_BUG */
33
34 /*
35  * Don't use BUG() or BUG_ON() unless there's really no way out; one
36  * example might be detecting data structure corruption in the middle
37  * of an operation that can't be backed out of.  If the (sub)system
38  * can somehow continue operating, perhaps with reduced functionality,
39  * it's probably not BUG-worthy.
40  *
41  * If you're tempted to BUG(), think again:  is completely giving up
42  * really the *only* solution?  There are usually better options, where
43  * users don't need to reboot ASAP and can mostly shut down cleanly.
44  */
45 #ifndef HAVE_ARCH_BUG
46 #define BUG() do { \
47         printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
48         panic("BUG!"); \
49 } while (0)
50 #endif
51
52 #ifndef HAVE_ARCH_BUG_ON
53 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
54 #endif
55
56 /*
57  * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
58  * significant issues that need prompt attention if they should ever
59  * appear at runtime.  Use the versions with printk format strings
60  * to provide better diagnostics.
61  */
62 #ifndef __WARN_TAINT
63 #ifndef __ASSEMBLY__
64 extern void warn_slowpath_fmt(const char *file, const int line,
65                 const char *fmt, ...) __attribute__((format(printf, 3, 4)));
66 extern void warn_slowpath_fmt_taint(const char *file, const int line,
67                                     unsigned taint, const char *fmt, ...)
68         __attribute__((format(printf, 4, 5)));
69 extern void warn_slowpath_null(const char *file, const int line);
70 #define WANT_WARN_ON_SLOWPATH
71 #endif
72 #define __WARN()                warn_slowpath_null(__FILE__, __LINE__)
73 #define __WARN_printf(arg...)   warn_slowpath_fmt(__FILE__, __LINE__, arg)
74 #define __WARN_printf_taint(taint, arg...)                              \
75         warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg)
76 #else
77 #define __WARN()                __WARN_TAINT(TAINT_WARN)
78 #define __WARN_printf(arg...)   do { printk(arg); __WARN(); } while (0)
79 #define __WARN_printf_taint(taint, arg...)                              \
80         do { printk(arg); __WARN_TAINT(taint); } while (0)
81 #endif
82
83 #ifndef WARN_ON
84 #define WARN_ON(condition) ({                                           \
85         int __ret_warn_on = !!(condition);                              \
86         if (unlikely(__ret_warn_on))                                    \
87                 __WARN();                                               \
88         unlikely(__ret_warn_on);                                        \
89 })
90 #endif
91
92 #ifndef WARN
93 #define WARN(condition, format...) ({                                           \
94         int __ret_warn_on = !!(condition);                              \
95         if (unlikely(__ret_warn_on))                                    \
96                 __WARN_printf(format);                                  \
97         unlikely(__ret_warn_on);                                        \
98 })
99 #endif
100
101 #define WARN_TAINT(condition, taint, format...) ({                      \
102         int __ret_warn_on = !!(condition);                              \
103         if (unlikely(__ret_warn_on))                                    \
104                 __WARN_printf_taint(taint, format);                     \
105         unlikely(__ret_warn_on);                                        \
106 })
107
108 #else /* !CONFIG_BUG */
109 #ifndef HAVE_ARCH_BUG
110 #define BUG() do {} while(0)
111 #endif
112
113 #ifndef HAVE_ARCH_BUG_ON
114 #define BUG_ON(condition) do { if (condition) ; } while(0)
115 #endif
116
117 #ifndef HAVE_ARCH_WARN_ON
118 #define WARN_ON(condition) ({                                           \
119         int __ret_warn_on = !!(condition);                              \
120         unlikely(__ret_warn_on);                                        \
121 })
122 #endif
123
124 #ifndef WARN
125 #define WARN(condition, format...) ({                                   \
126         int __ret_warn_on = !!(condition);                              \
127         unlikely(__ret_warn_on);                                        \
128 })
129 #endif
130
131 #define WARN_TAINT(condition, taint, format...) WARN_ON(condition)
132
133 #endif
134
135 #define WARN_ON_ONCE(condition) ({                              \
136         static bool __warned;                                   \
137         int __ret_warn_once = !!(condition);                    \
138                                                                 \
139         if (unlikely(__ret_warn_once))                          \
140                 if (WARN_ON(!__warned))                         \
141                         __warned = true;                        \
142         unlikely(__ret_warn_once);                              \
143 })
144
145 #define WARN_ONCE(condition, format...) ({                      \
146         static bool __warned;                                   \
147         int __ret_warn_once = !!(condition);                    \
148                                                                 \
149         if (unlikely(__ret_warn_once))                          \
150                 if (WARN(!__warned, format))                    \
151                         __warned = true;                        \
152         unlikely(__ret_warn_once);                              \
153 })
154
155 #define WARN_TAINT_ONCE(condition, taint, format...)    ({      \
156         static bool __warned;                                   \
157         int __ret_warn_once = !!(condition);                    \
158                                                                 \
159         if (unlikely(__ret_warn_once))                          \
160                 if (WARN_TAINT(!__warned, taint, format))       \
161                         __warned = true;                        \
162         unlikely(__ret_warn_once);                              \
163 })
164
165 /*
166  * WARN_ON_SMP() is for cases that the warning is either
167  * meaningless for !SMP or may even cause failures.
168  * This is usually used for cases that we have
169  * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked()
170  * returns 0 for uniprocessor settings.
171  * It can also be used with values that are only defined
172  * on SMP:
173  *
174  * struct foo {
175  *  [...]
176  * #ifdef CONFIG_SMP
177  *      int bar;
178  * #endif
179  * };
180  *
181  * void func(struct foo *zoot)
182  * {
183  *      WARN_ON_SMP(!zoot->bar);
184  *
185  * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
186  * and should be a nop and return false for uniprocessor.
187  *
188  * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
189  * and x is true.
190  */
191 #ifdef CONFIG_SMP
192 # define WARN_ON_SMP(x)                 WARN_ON(x)
193 #else
194 /*
195  * Use of ({0;}) because WARN_ON_SMP(x) may be used either as
196  * a stand alone line statement or as a condition in an if ()
197  * statement.
198  * A simple "0" would cause gcc to give a "statement has no effect"
199  * warning.
200  */
201 # define WARN_ON_SMP(x)                 ({0;})
202 #endif
203
204 #endif