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-rw-r--r--include/linux/export.h89
1 files changed, 89 insertions, 0 deletions
diff --git a/include/linux/export.h b/include/linux/export.h
new file mode 100644
index 000000000000..696c0f48afc7
--- /dev/null
+++ b/include/linux/export.h
@@ -0,0 +1,89 @@
+#ifndef _LINUX_EXPORT_H
+#define _LINUX_EXPORT_H
+/*
+ * Export symbols from the kernel to modules. Forked from module.h
+ * to reduce the amount of pointless cruft we feed to gcc when only
+ * exporting a simple symbol or two.
+ *
+ * If you feel the need to add #include <linux/foo.h> to this file
+ * then you are doing something wrong and should go away silently.
+ */
+
+/* Some toolchains use a `_' prefix for all user symbols. */
+#ifdef CONFIG_SYMBOL_PREFIX
+#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
+#else
+#define MODULE_SYMBOL_PREFIX ""
+#endif
+
+struct kernel_symbol
+{
+ unsigned long value;
+ const char *name;
+};
+
+#ifdef MODULE
+extern struct module __this_module;
+#define THIS_MODULE (&__this_module)
+#else
+#define THIS_MODULE ((struct module *)0)
+#endif
+
+#ifdef CONFIG_MODULES
+
+#ifndef __GENKSYMS__
+#ifdef CONFIG_MODVERSIONS
+/* Mark the CRC weak since genksyms apparently decides not to
+ * generate a checksums for some symbols */
+#define __CRC_SYMBOL(sym, sec) \
+ extern void *__crc_##sym __attribute__((weak)); \
+ static const unsigned long __kcrctab_##sym \
+ __used \
+ __attribute__((section("___kcrctab" sec "+" #sym), unused)) \
+ = (unsigned long) &__crc_##sym;
+#else
+#define __CRC_SYMBOL(sym, sec)
+#endif
+
+/* For every exported symbol, place a struct in the __ksymtab section */
+#define __EXPORT_SYMBOL(sym, sec) \
+ extern typeof(sym) sym; \
+ __CRC_SYMBOL(sym, sec) \
+ static const char __kstrtab_##sym[] \
+ __attribute__((section("__ksymtab_strings"), aligned(1))) \
+ = MODULE_SYMBOL_PREFIX #sym; \
+ static const struct kernel_symbol __ksymtab_##sym \
+ __used \
+ __attribute__((section("___ksymtab" sec "+" #sym), unused)) \
+ = { (unsigned long)&sym, __kstrtab_##sym }
+
+#define EXPORT_SYMBOL(sym) \
+ __EXPORT_SYMBOL(sym, "")
+
+#define EXPORT_SYMBOL_GPL(sym) \
+ __EXPORT_SYMBOL(sym, "_gpl")
+
+#define EXPORT_SYMBOL_GPL_FUTURE(sym) \
+ __EXPORT_SYMBOL(sym, "_gpl_future")
+
+#ifdef CONFIG_UNUSED_SYMBOLS
+#define EXPORT_UNUSED_SYMBOL(sym) __EXPORT_SYMBOL(sym, "_unused")
+#define EXPORT_UNUSED_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_unused_gpl")
+#else
+#define EXPORT_UNUSED_SYMBOL(sym)
+#define EXPORT_UNUSED_SYMBOL_GPL(sym)
+#endif
+
+#endif /* __GENKSYMS__ */
+
+#else /* !CONFIG_MODULES... */
+
+#define EXPORT_SYMBOL(sym)
+#define EXPORT_SYMBOL_GPL(sym)
+#define EXPORT_SYMBOL_GPL_FUTURE(sym)
+#define EXPORT_UNUSED_SYMBOL(sym)
+#define EXPORT_UNUSED_SYMBOL_GPL(sym)
+
+#endif /* CONFIG_MODULES */
+
+#endif /* _LINUX_EXPORT_H */