Driver core: let request_module() send a /sys/modules/kmod/-uevent

[linux-2.6-omap-h63xx.git] / kernel / kmod.c

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 796276141e51902bd466b1f5b81b5220c109ca4a..9f923f8ce6a0cd3c225f73eb79c865777ac60967 100644 (file)
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -36,6 +36,8 @@
 #include <linux/resource.h>
 #include <asm/uaccess.h>
 
+extern int delete_module(const char *name, unsigned int flags);
+
 extern int max_threads;
 
 static struct workqueue_struct *khelper_wq;
@@ -46,6 +48,7 @@ static struct workqueue_struct *khelper_wq;
        modprobe_path is set via /proc/sys.
 */
 char modprobe_path[KMOD_PATH_LEN] = "/sbin/modprobe";
+struct module_kobject kmod_mk;
 
 /**
  * request_module - try to load a kernel module
@@ -75,6 +78,11 @@ int request_module(const char *fmt, ...)
        static atomic_t kmod_concurrent = ATOMIC_INIT(0);
 #define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
        static int kmod_loop_msg;
+       char modalias[16 + MODULE_NAME_LEN] = "MODALIAS=";
+       char *uevent_envp[2] = {
+               modalias,
+               NULL
+       };
 
        va_start(args, fmt);
        ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
@@ -82,6 +90,12 @@ int request_module(const char *fmt, ...)
        if (ret >= MODULE_NAME_LEN)
                return -ENAMETOOLONG;
 
+       strcpy(&modalias[strlen("MODALIAS=")], module_name);
+       kobject_uevent_env(&kmod_mk.kobj, KOBJ_CHANGE, uevent_envp);
+
+       if (modprobe_path[0] == '\0')
+               goto out;
+
        /* If modprobe needs a service that is in a module, we get a recursive
         * loop.  Limit the number of running kmod threads to max_threads/2 or
         * MAX_KMOD_CONCURRENT, whichever is the smaller.  A cleaner method
@@ -108,9 +122,115 @@ int request_module(const char *fmt, ...)
 
        ret = call_usermodehelper(modprobe_path, argv, envp, 1);
        atomic_dec(&kmod_concurrent);
+out:
        return ret;
 }
 EXPORT_SYMBOL(request_module);
+
+static ssize_t store_mod_request(struct module_attribute *mattr,
+                                struct module *mod,
+                             const char *buffer, size_t count)
+{
+       char name[MODULE_NAME_LEN];
+       int ret;
+
+       if (count < 1 || count+1 > MODULE_NAME_LEN)
+               return -EINVAL;
+       memcpy(name, buffer, count);
+       name[count] = '\0';
+       if (name[count-1] == '\n')
+               name[count-1] = '\0';
+
+       ret = request_module(name);
+       if (ret < 0)
+               return ret;
+       return count;
+}
+
+static struct module_attribute mod_request = {
+       .attr = { .name = "mod_request", .mode = S_IWUSR, .owner = THIS_MODULE },
+       .store = store_mod_request,
+};
+
+#ifdef CONFIG_MODULE_UNLOAD
+static ssize_t store_mod_unload(struct module_attribute *mattr,
+                           struct module *mod,
+                           const char *buffer, size_t count)
+{
+       char name[MODULE_NAME_LEN];
+       int ret;
+
+       if (count < 1 || count+1 > MODULE_NAME_LEN)
+               return -EINVAL;
+       memcpy(name, buffer, count);
+       name[count] = '\0';
+       if (name[count-1] == '\n')
+               name[count-1] = '\0';
+
+       ret = delete_module(name, O_NONBLOCK);
+       if (ret < 0)
+               return ret;
+       return count;
+}
+
+static struct module_attribute mod_unload = {
+       .attr = { .name = "mod_unload", .mode = S_IWUSR, .owner = THIS_MODULE },
+       .store = store_mod_unload,
+};
+#endif
+
+static ssize_t show_mod_request_helper(struct module_attribute *mattr,
+                                      struct module *mod,
+                                      char *buffer)
+{
+       return sprintf(buffer, "%s\n", modprobe_path);
+}
+
+static ssize_t store_mod_request_helper(struct module_attribute *mattr,
+                                       struct module *mod,
+                                       const char *buffer, size_t count)
+{
+       if (count < 1 || count+1 > KMOD_PATH_LEN)
+               return -EINVAL;
+       memcpy(modprobe_path, buffer, count);
+       modprobe_path[count] = '\0';
+       if (modprobe_path[count-1] == '\n')
+               modprobe_path[count-1] = '\0';
+       return count;
+}
+
+static struct module_attribute mod_request_helper = {
+       .attr = {
+               .name = "mod_request_helper",
+               .mode = S_IWUSR | S_IRUGO,
+               .owner = THIS_MODULE
+       },
+       .show = show_mod_request_helper,
+       .store = store_mod_request_helper,
+};
+
+void __init kmod_sysfs_init(void)
+{
+       int ret;
+
+       kmod_mk.mod = THIS_MODULE;
+       kobj_set_kset_s(&kmod_mk, module_subsys);
+       kobject_set_name(&kmod_mk.kobj, "kmod");
+       kobject_init(&kmod_mk.kobj);
+       ret = kobject_add(&kmod_mk.kobj);
+       if (ret < 0)
+               goto out;
+
+       ret = sysfs_create_file(&kmod_mk.kobj, &mod_request_helper.attr);
+       ret = sysfs_create_file(&kmod_mk.kobj, &mod_request.attr);
+#ifdef CONFIG_MODULE_UNLOAD
+       ret = sysfs_create_file(&kmod_mk.kobj, &mod_unload.attr);
+#endif
+
+       kobject_uevent(&kmod_mk.kobj, KOBJ_ADD);
+out:
+       return;
+}
 #endif /* CONFIG_KMOD */
 
 struct subprocess_info {