[PATCH] lockdep: add is_module_address()

Add is_module_address() method - to be used by lockdep.

Signed-off-by: Ingo Molnar <[e-mail]>
Signed-off-by: Arjan van de Ven <[e-mail]>
Cc: Rusty Russell <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/module.h

···
 /* Is this address in a module? (second is with no locks, for oops) */
 struct module *module_text_address(unsigned long addr);
 struct module *__module_text_address(unsigned long addr);
+int is_module_address(unsigned long addr);
 
 /* Returns module and fills in value, defined and namebuf, or NULL if
    symnum out of range. */
···
 static inline struct module *__module_text_address(unsigned long addr)
 {
 	return NULL;
+}
+
+static inline int is_module_address(unsigned long addr)
+{
+	return 0;
 }
 
 /* Get/put a kernel symbol (calls should be symmetric) */

kernel/module.c

···
 	return e;
 }
 
+/*
+ * Is this a valid module address?
+ */
+int is_module_address(unsigned long addr)
+{
+	unsigned long flags;
+	struct module *mod;
+
+	spin_lock_irqsave(&modlist_lock, flags);
+
+	list_for_each_entry(mod, &modules, list) {
+		if (within(addr, mod->module_core, mod->core_size)) {
+			spin_unlock_irqrestore(&modlist_lock, flags);
+			return 1;
+		}
+	}
+
+	spin_unlock_irqrestore(&modlist_lock, flags);
+
+	return 0;
+}
+
+
 /* Is this a valid kernel address?  We don't grab the lock: we are oopsing. */
 struct module *__module_text_address(unsigned long addr)
 {