module: show version information for built-in modules in sysfs
Currently only drivers that are built as modules have their versions
shown in /sys/module/<module_name>/version, but this information might
also be useful for built-in drivers as well. This especially important
for drivers that do not define any parameters - such drivers, if
built-in, are completely invisible from userspace.
This patch changes MODULE_VERSION() macro so that in case when we are
compiling built-in module, version information is stored in a separate
section. Kernel then uses this data to create 'version' sysfs attribute
in the same fashion it creates attributes for module parameters.
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/include/linux/module.h b/include/linux/module.h
index 8b17fd8..50efcd3 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -58,6 +58,12 @@
void (*free)(struct module *);
};
+struct module_version_attribute {
+ struct module_attribute mattr;
+ const char *module_name;
+ const char *version;
+};
+
struct module_kobject
{
struct kobject kobj;
@@ -161,7 +167,28 @@
Using this automatically adds a checksum of the .c files and the
local headers in "srcversion".
*/
+
+#ifdef MODULE
#define MODULE_VERSION(_version) MODULE_INFO(version, _version)
+#else
+#define MODULE_VERSION(_version) \
+ extern ssize_t __modver_version_show(struct module_attribute *, \
+ struct module *, char *); \
+ static struct module_version_attribute __modver_version_attr \
+ __used \
+ __attribute__ ((__section__ ("__modver"),aligned(sizeof(void *)))) \
+ = { \
+ .mattr = { \
+ .attr = { \
+ .name = "version", \
+ .mode = S_IRUGO, \
+ }, \
+ .show = __modver_version_show, \
+ }, \
+ .module_name = KBUILD_MODNAME, \
+ .version = _version, \
+ }
+#endif
/* Optional firmware file (or files) needed by the module
* format is simply firmware file name. Multiple firmware