1 files changed, 142 insertions, 0 deletions
diff --git a/include/linux/bug.h b/include/linux/bug.h
new file mode 100644
index 000000000000..bcfd70c217a3
--- /dev/null
+++ b/include/linux/bug.h
@@ -0,0 +1,142 @@
+#ifndef _LINUX_BUG_H
+#define _LINUX_BUG_H
+
+#include <asm/bug.h>
+#include <linux/compiler.h>
+
+enum bug_trap_type {
+	BUG_TRAP_TYPE_NONE = 0,
+	BUG_TRAP_TYPE_WARN = 1,
+	BUG_TRAP_TYPE_BUG = 2,
+};
+
+struct pt_regs;
+
+#ifdef __CHECKER__
+#define BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
+#define BUILD_BUG_ON_ZERO(e) (0)
+#define BUILD_BUG_ON_NULL(e) ((void*)0)
+#define BUILD_BUG_ON_INVALID(e) (0)
+#define BUILD_BUG_ON_MSG(cond, msg) (0)
+#define BUILD_BUG_ON(condition) (0)
+#define BUILD_BUG() (0)
+#else /* __CHECKER__ */
+
+/* Force a compilation error if a constant expression is not a power of 2 */
+#define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
+	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
+
+/* Force a compilation error if condition is true, but also produce a
+   result (of value 0 and type size_t), so the expression can be used
+   e.g. in a structure initializer (or where-ever else comma expressions
+   aren't permitted). */
+#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
+#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
+
+/*
+ * BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the
+ * expression but avoids the generation of any code, even if that expression
+ * has side-effects.
+ */
+#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
+
+/**
+ * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied
+ *		      error message.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * See BUILD_BUG_ON for description.
+ */
+#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
+
+/**
+ * BUILD_BUG_ON - break compile if a condition is true.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * If you have some code which relies on certain constants being equal, or
+ * some other compile-time-evaluated condition, you should use BUILD_BUG_ON to
+ * detect if someone changes it.
+ *
+ * The implementation uses gcc's reluctance to create a negative array, but gcc
+ * (as of 4.4) only emits that error for obvious cases (e.g. not arguments to
+ * inline functions).  Luckily, in 4.3 they added the "error" function
+ * attribute just for this type of case.  Thus, we use a negative sized array
+ * (should always create an error on gcc versions older than 4.4) and then call
+ * an undefined function with the error attribute (should always create an
+ * error on gcc 4.3 and later).  If for some reason, neither creates a
+ * compile-time error, we'll still have a link-time error, which is harder to
+ * track down.
+ */
+#ifndef __OPTIMIZE__
+#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
+#else
+#define BUILD_BUG_ON(condition) \
+	BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
+#endif
+
+/**
+ * BUILD_BUG - break compile if used.
+ *
+ * If you have some code that you expect the compiler to eliminate at
+ * build time, you should use BUILD_BUG to detect if it is
+ * unexpectedly used.
+ */
+#define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
+
+#endif	/* __CHECKER__ */
+
+#ifdef CONFIG_GENERIC_BUG
+#include <asm-generic/bug.h>
+
+static inline int is_warning_bug(const struct bug_entry *bug)
+{
+	return bug->flags & BUGFLAG_WARNING;
+}
+
+const struct bug_entry *find_bug(unsigned long bugaddr);
+
+enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs);
+
+/* These are defined by the architecture */
+int is_valid_bugaddr(unsigned long addr);
+
+#else	/* !CONFIG_GENERIC_BUG */
+
+static inline void *find_bug(unsigned long bugaddr)
+{
+	return NULL;
+}
+
+static inline enum bug_trap_type report_bug(unsigned long bug_addr,
+					    struct pt_regs *regs)
+{
+	return BUG_TRAP_TYPE_BUG;
+}
+
+#endif	/* CONFIG_GENERIC_BUG */
+
+#ifdef CONFIG_PANIC_ON_DATA_CORRUPTION
+#define PANIC_CORRUPTION 1
+#else
+#define PANIC_CORRUPTION 0
+#endif  /* CONFIG_PANIC_ON_DATA_CORRUPTION */
+
+/*
+ * Since detected data corruption should stop operation on the affected
+ * structures. Return value must be checked and sanely acted on by caller.
+ */
+static inline __must_check bool check_data_corruption(bool v) { return v; }
+#define CHECK_DATA_CORRUPTION(condition, fmt, ...)			 \
+	check_data_corruption(({					 \
+		bool corruption = unlikely(condition);			 \
+		if (corruption) {					 \
+			if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
+				pr_err(fmt, ##__VA_ARGS__);		 \
+				BUG();					 \
+			} else						 \
+				WARN(1, fmt, ##__VA_ARGS__);		 \
+		}							 \
+		corruption;						 \
+	}))
+
+#endif	/* _LINUX_BUG_H */