[RFC PATCH 5/8] module: add function to map address to containing module

Peter Oberparleiter
2008-04-21T12:35:57Z

From: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>

module_address() maps an address to the module containing it in either
text or data section. Required by the gcov profiling infrastructure to
associate profiling data structures with modules.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
---
include/linux/module.h | 1 +
kernel/module.c | 23 ++++++++++++++++++-----
2 files changed, 19 insertions(+), 5 deletions(-)

Index: linux-2.6.25/include/linux/module.h
===================================================================
--- linux-2.6.25.orig/include/linux/module.h
+++ linux-2.6.25/include/linux/module.h
@@ -380,6 +380,7 @@ static inline int module_is_live(struct
/* 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);
+struct module *module_address(unsigned long addr);
int is_module_address(unsigned long addr);

/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
Index: linux-2.6.25/kernel/module.c
===================================================================
--- linux-2.6.25.orig/kernel/module.c
+++ linux-2.6.25/kernel/module.c
@@ -2527,10 +2527,16 @@ const struct exception_table_entry *sear
return e;
}

-/*
- * Is this a valid module address?
+/**
+ * module_address - map an address to the containing module
+ * @addr: address for which the containing module should be searched
+ *
+ * Return the module which contains the address in either text or data
+ * section. Return NULL if no matching module was found. Callers should
+ * be aware that no reference counting is being performed for the returned
+ * module reference.
*/
-int is_module_address(unsigned long addr)
+struct module *module_address(unsigned long addr)
{
struct module *mod;

@@ -2539,15 +2545,22 @@ int is_module_address(unsigned long addr
list_for_each_entry(mod, &modules, list) {
if (within(addr, mod->module_core, mod->core_size)) {
preempt_enable();
- return 1;
+ return mod;
}
}

preempt_enable();

- return 0;
+ return NULL;
}

+/*
+ * Is this a valid module address?
+ */
+int is_module_address(unsigned long addr)
+{
+ return module_address(addr) ? 1 : 0;
+}

/* Is this a valid kernel address? */
struct module *__module_text_address(unsigned long addr)