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-rw-r--r--include/linux/jump_label.h74
1 files changed, 74 insertions, 0 deletions
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
new file mode 100644
index 00000000000..b67cb180e6e
--- /dev/null
+++ b/include/linux/jump_label.h
@@ -0,0 +1,74 @@
+#ifndef _LINUX_JUMP_LABEL_H
+#define _LINUX_JUMP_LABEL_H
+
+#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_HAVE_ARCH_JUMP_LABEL)
+# include <asm/jump_label.h>
+# define HAVE_JUMP_LABEL
+#endif
+
+enum jump_label_type {
+ JUMP_LABEL_ENABLE,
+ JUMP_LABEL_DISABLE
+};
+
+struct module;
+
+#ifdef HAVE_JUMP_LABEL
+
+extern struct jump_entry __start___jump_table[];
+extern struct jump_entry __stop___jump_table[];
+
+extern void arch_jump_label_transform(struct jump_entry *entry,
+ enum jump_label_type type);
+extern void arch_jump_label_text_poke_early(jump_label_t addr);
+extern void jump_label_update(unsigned long key, enum jump_label_type type);
+extern void jump_label_apply_nops(struct module *mod);
+extern int jump_label_text_reserved(void *start, void *end);
+
+#define jump_label_enable(key) \
+ jump_label_update((unsigned long)key, JUMP_LABEL_ENABLE);
+
+#define jump_label_disable(key) \
+ jump_label_update((unsigned long)key, JUMP_LABEL_DISABLE);
+
+#else
+
+#define JUMP_LABEL(key, label) \
+do { \
+ if (unlikely(*key)) \
+ goto label; \
+} while (0)
+
+#define jump_label_enable(cond_var) \
+do { \
+ *(cond_var) = 1; \
+} while (0)
+
+#define jump_label_disable(cond_var) \
+do { \
+ *(cond_var) = 0; \
+} while (0)
+
+static inline int jump_label_apply_nops(struct module *mod)
+{
+ return 0;
+}
+
+static inline int jump_label_text_reserved(void *start, void *end)
+{
+ return 0;
+}
+
+#endif
+
+#define COND_STMT(key, stmt) \
+do { \
+ __label__ jl_enabled; \
+ JUMP_LABEL(key, jl_enabled); \
+ if (0) { \
+jl_enabled: \
+ stmt; \
+ } \
+} while (0)
+
+#endif