1 /* 2 * module.c - module sysfs fun for drivers 3 * 4 * This file is released under the GPLv2 5 * 6 */ 7 #include <linux/device.h> 8 #include <linux/module.h> 9 #include <linux/errno.h> 10 #include <linux/string.h> 11 #include "base.h" 12 13 static char *make_driver_name(struct device_driver *drv) 14 { 15 char *driver_name; 16 17 driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2, 18 GFP_KERNEL); 19 if (!driver_name) 20 return NULL; 21 22 sprintf(driver_name, "%s:%s", drv->bus->name, drv->name); 23 return driver_name; 24 } 25 26 static void module_create_drivers_dir(struct module_kobject *mk) 27 { 28 if (!mk || mk->drivers_dir) 29 return; 30 31 mk->drivers_dir = kobject_create_and_add("drivers", &mk->kobj); 32 } 33 34 void module_add_driver(struct module *mod, struct device_driver *drv) 35 { 36 char *driver_name; 37 int no_warn; 38 struct module_kobject *mk = NULL; 39 40 if (!drv) 41 return; 42 43 if (mod) 44 mk = &mod->mkobj; 45 else if (drv->mod_name) { 46 struct kobject *mkobj; 47 48 /* Lookup built-in module entry in /sys/modules */ 49 mkobj = kset_find_obj(module_kset, drv->mod_name); 50 if (mkobj) { 51 mk = container_of(mkobj, struct module_kobject, kobj); 52 /* remember our module structure */ 53 drv->p->mkobj = mk; 54 /* kset_find_obj took a reference */ 55 kobject_put(mkobj); 56 } 57 } 58 59 if (!mk) 60 return; 61 62 /* Don't check return codes; these calls are idempotent */ 63 no_warn = sysfs_create_link(&drv->p->kobj, &mk->kobj, "module"); 64 driver_name = make_driver_name(drv); 65 if (driver_name) { 66 module_create_drivers_dir(mk); 67 no_warn = sysfs_create_link(mk->drivers_dir, &drv->p->kobj, 68 driver_name); 69 kfree(driver_name); 70 } 71 } 72 73 void module_remove_driver(struct device_driver *drv) 74 { 75 struct module_kobject *mk = NULL; 76 char *driver_name; 77 78 if (!drv) 79 return; 80 81 sysfs_remove_link(&drv->p->kobj, "module"); 82 83 if (drv->owner) 84 mk = &drv->owner->mkobj; 85 else if (drv->p->mkobj) 86 mk = drv->p->mkobj; 87 if (mk && mk->drivers_dir) { 88 driver_name = make_driver_name(drv); 89 if (driver_name) { 90 sysfs_remove_link(mk->drivers_dir, driver_name); 91 kfree(driver_name); 92 } 93 } 94 } 95