1 files changed, 45 insertions, 19 deletions

diff --git a/include/linux/export.h b/include/linux/export.h
index b768d6dd3c90..ce764a5d2ee4 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -10,20 +10,7 @@
  * hackers place grumpy comments in header files.
  */
 
-#define __VMLINUX_SYMBOL(x) x
-#define __VMLINUX_SYMBOL_STR(x) #x
-
-/* Indirect, so macros are expanded before pasting. */
-#define VMLINUX_SYMBOL(x) __VMLINUX_SYMBOL(x)
-#define VMLINUX_SYMBOL_STR(x) __VMLINUX_SYMBOL_STR(x)
-
 #ifndef __ASSEMBLY__
-struct kernel_symbol
-{
-        unsigned long value;
-        const char *name;
-};
-
 #ifdef MODULE
 extern struct module __this_module;
 #define THIS_MODULE (&__this_module)
@@ -54,19 +41,58 @@ extern struct module __this_module;
 #define __CRC_SYMBOL(sym, sec)
 #endif
 
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+#include <linux/compiler.h>
+/*
+ * Emit the ksymtab entry as a pair of relative references: this reduces
+ * the size by half on 64-bit architectures, and eliminates the need for
+ * absolute relocations that require runtime processing on relocatable
+ * kernels.
+ */
+#define __KSYMTAB_ENTRY(sym, sec)                                       \
+        __ADDRESSABLE(sym)                                              \
+        asm("   .section \"___ksymtab" sec "+" #sym "\", \"a\"  \n"     \
+            "   .balign 8                                       \n"     \
+            "__ksymtab_" #sym ":                                \n"     \
+            "   .long   " #sym "- .                             \n"     \
+            "   .long   __kstrtab_" #sym "- .                   \n"     \
+            "   .previous                                       \n")
+
+struct kernel_symbol {
+        int value_offset;
+        int name_offset;
+};
+#else
+#define __KSYMTAB_ENTRY(sym, sec)                                       \
+        static const struct kernel_symbol __ksymtab_##sym               \
+        __attribute__((section("___ksymtab" sec "+" #sym), used))       \
+        = { (unsigned long)&sym, __kstrtab_##sym }
+
+struct kernel_symbol {
+        unsigned long value;
+        const char *name;
+};
+#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)))       \
+        __attribute__((section("__ksymtab_strings"), used, aligned(1))) \
         = #sym;                                                         \
-        static const struct kernel_symbol __ksymtab_##sym               \
-        __used                                                          \
-        __attribute__((section("___ksymtab" sec "+" #sym), used))       \
-        = { (unsigned long)&sym, __kstrtab_##sym }
+        __KSYMTAB_ENTRY(sym, sec)
+
+#if defined(__DISABLE_EXPORTS)
+
+/*
+ * Allow symbol exports to be disabled completely so that C code may
+ * be reused in other execution contexts such as the UEFI stub or the
+ * decompressor.
+ */
+#define __EXPORT_SYMBOL(sym, sec)
 
-#if defined(__KSYM_DEPS__)
+#elif defined(__KSYM_DEPS__)
 
 /*
  * For fine grained build dependencies, we want to tell the build system