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_GENERIC_BUG
   7 #define BUGFLAG_WARNING         (1 << 0)
   8 #define BUGFLAG_TAINT(taint)    (BUGFLAG_WARNING | ((taint) << 8))
   9 #define BUG_GET_TAINT(bug)      ((bug)->flags >> 8)
  10 #endif
  11
  12 #ifndef __ASSEMBLY__
  13 #include <linux/kernel.h>
  14
  15 #ifdef CONFIG_BUG
  16
  17 #ifdef CONFIG_GENERIC_BUG
  18 struct bug_entry {
  19 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
  20         unsigned long   bug_addr;
  21 #else
  22         signed int      bug_addr_disp;
  23 #endif
  24 #ifdef CONFIG_DEBUG_BUGVERBOSE
  25 #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
  26         const char      *file;
  27 #else
  28         signed int      file_disp;
  29 #endif
  30         unsigned short  line;
  31 #endif
  32         unsigned short  flags;
  33 };
  34 #endif  /* CONFIG_GENERIC_BUG */
  35
  36 /*
  37  * Don't use BUG() or BUG_ON() unless there's really no way out; one
  38  * example might be detecting data structure corruption in the middle
  39  * of an operation that can't be backed out of.  If the (sub)system
  40  * can somehow continue operating, perhaps with reduced functionality,
  41  * it's probably not BUG-worthy.
  42  *
  43  * If you're tempted to BUG(), think again:  is completely giving up
  44  * really the *only* solution?  There are usually better options, where
  45  * users don't need to reboot ASAP and can mostly shut down cleanly.
  46  */
  47 #ifndef HAVE_ARCH_BUG
  48 #define BUG() do { \
  49         printk("BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
  50         panic("BUG!"); \
  51 } while (0)
  52 #endif
  53
  54 #ifndef HAVE_ARCH_BUG_ON
  55 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
  56 #endif
  57
  58 /*
  59  * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
  60  * significant issues that need prompt attention if they should ever
  61  * appear at runtime.  Use the versions with printk format strings
  62  * to provide better diagnostics.
  63  */
  64 #ifndef __WARN_TAINT
  65 extern __printf(3, 4)
  66 void warn_slowpath_fmt(const char *file, const int line,
  67                        const char *fmt, ...);
  68 extern __printf(4, 5)
  69 void warn_slowpath_fmt_taint(const char *file, const int line, unsigned taint,
  70                              const char *fmt, ...);
  71 extern void warn_slowpath_null(const char *file, const int line);
  72 #define WANT_WARN_ON_SLOWPATH
  73 #define __WARN()                warn_slowpath_null(__FILE__, __LINE__)
  74 #define __WARN_printf(arg...)   warn_slowpath_fmt(__FILE__, __LINE__, arg)
  75 #define __WARN_printf_taint(taint, arg...)                              \
  76         warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg)
  77 #else
  78 #define __WARN()                __WARN_TAINT(TAINT_WARN)
  79 #define __WARN_printf(arg...)   do { printk(arg); __WARN(); } while (0)
  80 #define __WARN_printf_taint(taint, arg...)                              \
  81         do { printk(arg); __WARN_TAINT(taint); } while (0)
  82 #endif
  83
  84 #ifndef WARN_ON
  85 #define WARN_ON(condition) ({                                           \
  86         int __ret_warn_on = !!(condition);                              \
  87         if (unlikely(__ret_warn_on))                                    \
  88                 __WARN();                                               \
  89         unlikely(__ret_warn_on);                                        \
  90 })
  91 #endif
  92
  93 #ifndef WARN
  94 #define WARN(condition, format...) ({                                           \
  95         int __ret_warn_on = !!(condition);                              \
  96         if (unlikely(__ret_warn_on))                                    \
  97                 __WARN_printf(format);                                  \
  98         unlikely(__ret_warn_on);                                        \
  99 })
 100 #endif
 101
 102 #define WARN_TAINT(condition, taint, format...) ({                      \
 103         int __ret_warn_on = !!(condition);                              \
 104         if (unlikely(__ret_warn_on))                                    \
 105                 __WARN_printf_taint(taint, format);                     \
 106         unlikely(__ret_warn_on);                                        \
 107 })
 108
 109 #define WARN_ON_ONCE(condition) ({                              \
 110         static bool __section(.data.unlikely) __warned;         \
 111         int __ret_warn_once = !!(condition);                    \
 112                                                                 \
 113         if (unlikely(__ret_warn_once))                          \
 114                 if (WARN_ON(!__warned))                         \
 115                         __warned = true;                        \
 116         unlikely(__ret_warn_once);                              \
 117 })
 118
 119 #define WARN_ONCE(condition, format...) ({                      \
 120         static bool __section(.data.unlikely) __warned;         \
 121         int __ret_warn_once = !!(condition);                    \
 122                                                                 \
 123         if (unlikely(__ret_warn_once))                          \
 124                 if (WARN(!__warned, format))                    \
 125                         __warned = true;                        \
 126         unlikely(__ret_warn_once);                              \
 127 })
 128
 129 #define WARN_TAINT_ONCE(condition, taint, format...)    ({      \
 130         static bool __section(.data.unlikely) __warned;         \
 131         int __ret_warn_once = !!(condition);                    \
 132                                                                 \
 133         if (unlikely(__ret_warn_once))                          \
 134                 if (WARN_TAINT(!__warned, taint, format))       \
 135                         __warned = true;                        \
 136         unlikely(__ret_warn_once);                              \
 137 })
 138
 139 #else /* !CONFIG_BUG */
 140 #ifndef HAVE_ARCH_BUG
 141 #define BUG() do {} while (1)
 142 #endif
 143
 144 #ifndef HAVE_ARCH_BUG_ON
 145 #define BUG_ON(condition) do { if (condition) ; } while (0)
 146 #endif
 147
 148 #ifndef HAVE_ARCH_WARN_ON
 149 #define WARN_ON(condition) ({                                           \
 150         int __ret_warn_on = !!(condition);                              \
 151         unlikely(__ret_warn_on);                                        \
 152 })
 153 #endif
 154
 155 #ifndef WARN
 156 #define WARN(condition, format...) ({                                   \
 157         int __ret_warn_on = !!(condition);                              \
 158         no_printk(format);                                              \
 159         unlikely(__ret_warn_on);                                        \
 160 })
 161 #endif
 162
 163 #define WARN_ON_ONCE(condition) WARN_ON(condition)
 164 #define WARN_ONCE(condition, format...) WARN(condition, format)
 165 #define WARN_TAINT(condition, taint, format...) WARN(condition, format)
 166 #define WARN_TAINT_ONCE(condition, taint, format...) WARN(condition, format)
 167
 168 #endif
 169
 170 /*
 171  * WARN_ON_SMP() is for cases that the warning is either
 172  * meaningless for !SMP or may even cause failures.
 173  * This is usually used for cases that we have
 174  * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked()
 175  * returns 0 for uniprocessor settings.
 176  * It can also be used with values that are only defined
 177  * on SMP:
 178  *
 179  * struct foo {
 180  *  [...]
 181  * #ifdef CONFIG_SMP
 182  *      int bar;
 183  * #endif
 184  * };
 185  *
 186  * void func(struct foo *zoot)
 187  * {
 188  *      WARN_ON_SMP(!zoot->bar);
 189  *
 190  * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(),
 191  * and should be a nop and return false for uniprocessor.
 192  *
 193  * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set
 194  * and x is true.
 195  */
 196 #ifdef CONFIG_SMP
 197 # define WARN_ON_SMP(x)                 WARN_ON(x)
 198 #else
 199 /*
 200  * Use of ({0;}) because WARN_ON_SMP(x) may be used either as
 201  * a stand alone line statement or as a condition in an if ()
 202  * statement.
 203  * A simple "0" would cause gcc to give a "statement has no effect"
 204  * warning.
 205  */
 206 # define WARN_ON_SMP(x)                 ({0;})
 207 #endif
 208
 209 #endif /* __ASSEMBLY__ */
 210
 211 #endif