Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * kobject.c - library routines for handling generic kernel objects |
| 3 | * |
| 4 | * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org> |
| 5 | * |
| 6 | * This file is released under the GPLv2. |
| 7 | * |
| 8 | * |
| 9 | * Please see the file Documentation/kobject.txt for critical information |
| 10 | * about using the kobject interface. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/kobject.h> |
| 14 | #include <linux/string.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/stat.h> |
Tim Schmielau | 4e57b68 | 2005-10-30 15:03:48 -0800 | [diff] [blame] | 17 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | |
| 19 | /** |
| 20 | * populate_dir - populate directory with attributes. |
| 21 | * @kobj: object we're working on. |
| 22 | * |
| 23 | * Most subsystems have a set of default attributes that |
| 24 | * are associated with an object that registers with them. |
| 25 | * This is a helper called during object registration that |
| 26 | * loops through the default attributes of the subsystem |
| 27 | * and creates attributes files for them in sysfs. |
| 28 | * |
| 29 | */ |
| 30 | |
| 31 | static int populate_dir(struct kobject * kobj) |
| 32 | { |
| 33 | struct kobj_type * t = get_ktype(kobj); |
| 34 | struct attribute * attr; |
| 35 | int error = 0; |
| 36 | int i; |
| 37 | |
| 38 | if (t && t->default_attrs) { |
| 39 | for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) { |
| 40 | if ((error = sysfs_create_file(kobj,attr))) |
| 41 | break; |
| 42 | } |
| 43 | } |
| 44 | return error; |
| 45 | } |
| 46 | |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 47 | static int create_dir(struct kobject * kobj, struct dentry *shadow_parent) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | { |
| 49 | int error = 0; |
| 50 | if (kobject_name(kobj)) { |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 51 | error = sysfs_create_dir(kobj, shadow_parent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | if (!error) { |
| 53 | if ((error = populate_dir(kobj))) |
| 54 | sysfs_remove_dir(kobj); |
| 55 | } |
| 56 | } |
| 57 | return error; |
| 58 | } |
| 59 | |
| 60 | static inline struct kobject * to_kobj(struct list_head * entry) |
| 61 | { |
| 62 | return container_of(entry,struct kobject,entry); |
| 63 | } |
| 64 | |
| 65 | static int get_kobj_path_length(struct kobject *kobj) |
| 66 | { |
| 67 | int length = 1; |
| 68 | struct kobject * parent = kobj; |
| 69 | |
| 70 | /* walk up the ancestors until we hit the one pointing to the |
| 71 | * root. |
| 72 | * Add 1 to strlen for leading '/' of each level. |
| 73 | */ |
| 74 | do { |
Chuck Ebbert | b365b3d | 2006-01-12 20:02:00 -0500 | [diff] [blame] | 75 | if (kobject_name(parent) == NULL) |
| 76 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | length += strlen(kobject_name(parent)) + 1; |
| 78 | parent = parent->parent; |
| 79 | } while (parent); |
| 80 | return length; |
| 81 | } |
| 82 | |
| 83 | static void fill_kobj_path(struct kobject *kobj, char *path, int length) |
| 84 | { |
| 85 | struct kobject * parent; |
| 86 | |
| 87 | --length; |
| 88 | for (parent = kobj; parent; parent = parent->parent) { |
| 89 | int cur = strlen(kobject_name(parent)); |
| 90 | /* back up enough to print this name with '/' */ |
| 91 | length -= cur; |
| 92 | strncpy (path + length, kobject_name(parent), cur); |
| 93 | *(path + --length) = '/'; |
| 94 | } |
| 95 | |
| 96 | pr_debug("%s: path = '%s'\n",__FUNCTION__,path); |
| 97 | } |
| 98 | |
| 99 | /** |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 100 | * kobject_get_path - generate and return the path associated with a given kobj and kset pair. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | * |
| 102 | * @kobj: kobject in question, with which to build the path |
| 103 | * @gfp_mask: the allocation type used to allocate the path |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 104 | * |
| 105 | * The result must be freed by the caller with kfree(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | */ |
Al Viro | fd4f2df | 2005-10-21 03:18:50 -0400 | [diff] [blame] | 107 | char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | { |
| 109 | char *path; |
| 110 | int len; |
| 111 | |
| 112 | len = get_kobj_path_length(kobj); |
Chuck Ebbert | b365b3d | 2006-01-12 20:02:00 -0500 | [diff] [blame] | 113 | if (len == 0) |
| 114 | return NULL; |
Burman Yan | 4668edc | 2006-12-06 20:38:51 -0800 | [diff] [blame] | 115 | path = kzalloc(len, gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | if (!path) |
| 117 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | fill_kobj_path(kobj, path, len); |
| 119 | |
| 120 | return path; |
| 121 | } |
Dmitry Torokhov | 80fc9f5 | 2006-10-11 01:43:58 -0400 | [diff] [blame] | 122 | EXPORT_SYMBOL_GPL(kobject_get_path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
| 124 | /** |
| 125 | * kobject_init - initialize object. |
| 126 | * @kobj: object in question. |
| 127 | */ |
| 128 | void kobject_init(struct kobject * kobj) |
| 129 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 130 | if (!kobj) |
| 131 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | kref_init(&kobj->kref); |
| 133 | INIT_LIST_HEAD(&kobj->entry); |
NeilBrown | 4508a7a | 2006-03-20 17:53:53 +1100 | [diff] [blame] | 134 | init_waitqueue_head(&kobj->poll); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | kobj->kset = kset_get(kobj->kset); |
| 136 | } |
| 137 | |
| 138 | |
| 139 | /** |
| 140 | * unlink - remove kobject from kset list. |
| 141 | * @kobj: kobject. |
| 142 | * |
| 143 | * Remove the kobject from the kset list and decrement |
| 144 | * its parent's refcount. |
| 145 | * This is separated out, so we can use it in both |
| 146 | * kobject_del() and kobject_add() on error. |
| 147 | */ |
| 148 | |
| 149 | static void unlink(struct kobject * kobj) |
| 150 | { |
| 151 | if (kobj->kset) { |
| 152 | spin_lock(&kobj->kset->list_lock); |
| 153 | list_del_init(&kobj->entry); |
| 154 | spin_unlock(&kobj->kset->list_lock); |
| 155 | } |
| 156 | kobject_put(kobj); |
| 157 | } |
| 158 | |
| 159 | /** |
| 160 | * kobject_add - add an object to the hierarchy. |
| 161 | * @kobj: object. |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 162 | * @shadow_parent: sysfs directory to add to. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | */ |
| 164 | |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 165 | int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | { |
| 167 | int error = 0; |
| 168 | struct kobject * parent; |
| 169 | |
| 170 | if (!(kobj = kobject_get(kobj))) |
| 171 | return -ENOENT; |
| 172 | if (!kobj->k_name) |
| 173 | kobj->k_name = kobj->name; |
Greg Kroah-Hartman | c171fef | 2006-01-20 14:08:59 -0800 | [diff] [blame] | 174 | if (!kobj->k_name) { |
| 175 | pr_debug("kobject attempted to be registered with no name!\n"); |
| 176 | WARN_ON(1); |
| 177 | return -EINVAL; |
| 178 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | parent = kobject_get(kobj->parent); |
| 180 | |
| 181 | pr_debug("kobject %s: registering. parent: %s, set: %s\n", |
| 182 | kobject_name(kobj), parent ? kobject_name(parent) : "<NULL>", |
| 183 | kobj->kset ? kobj->kset->kobj.name : "<NULL>" ); |
| 184 | |
| 185 | if (kobj->kset) { |
| 186 | spin_lock(&kobj->kset->list_lock); |
| 187 | |
| 188 | if (!parent) |
| 189 | parent = kobject_get(&kobj->kset->kobj); |
| 190 | |
| 191 | list_add_tail(&kobj->entry,&kobj->kset->list); |
| 192 | spin_unlock(&kobj->kset->list_lock); |
| 193 | } |
| 194 | kobj->parent = parent; |
| 195 | |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 196 | error = create_dir(kobj, shadow_parent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | if (error) { |
| 198 | /* unlink does the kobject_put() for us */ |
| 199 | unlink(kobj); |
Mariusz Kozlowski | b067db4 | 2007-01-02 13:44:44 +0100 | [diff] [blame] | 200 | kobject_put(parent); |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 201 | |
| 202 | /* be noisy on error issues */ |
| 203 | if (error == -EEXIST) |
Greg Kroah-Hartman | 183bd5b | 2006-05-18 10:39:21 -0700 | [diff] [blame] | 204 | printk("kobject_add failed for %s with -EEXIST, " |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 205 | "don't try to register things with the " |
| 206 | "same name in the same directory.\n", |
| 207 | kobject_name(kobj)); |
| 208 | else |
Greg Kroah-Hartman | 183bd5b | 2006-05-18 10:39:21 -0700 | [diff] [blame] | 209 | printk("kobject_add failed for %s (%d)\n", |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 210 | kobject_name(kobj), error); |
Greg Kroah-Hartman | 183bd5b | 2006-05-18 10:39:21 -0700 | [diff] [blame] | 211 | dump_stack(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | } |
| 213 | |
| 214 | return error; |
| 215 | } |
| 216 | |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 217 | /** |
| 218 | * kobject_add - add an object to the hierarchy. |
| 219 | * @kobj: object. |
| 220 | */ |
| 221 | int kobject_add(struct kobject * kobj) |
| 222 | { |
| 223 | return kobject_shadow_add(kobj, NULL); |
| 224 | } |
| 225 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | |
| 227 | /** |
| 228 | * kobject_register - initialize and add an object. |
| 229 | * @kobj: object in question. |
| 230 | */ |
| 231 | |
| 232 | int kobject_register(struct kobject * kobj) |
| 233 | { |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 234 | int error = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | if (kobj) { |
| 236 | kobject_init(kobj); |
| 237 | error = kobject_add(kobj); |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 238 | if (!error) |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 239 | kobject_uevent(kobj, KOBJ_ADD); |
Greg Kroah-Hartman | dcd0da0 | 2006-03-20 13:17:13 -0800 | [diff] [blame] | 240 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | return error; |
| 242 | } |
| 243 | |
| 244 | |
| 245 | /** |
| 246 | * kobject_set_name - Set the name of an object |
| 247 | * @kobj: object. |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 248 | * @fmt: format string used to build the name |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | * |
| 250 | * If strlen(name) >= KOBJ_NAME_LEN, then use a dynamically allocated |
| 251 | * string that @kobj->k_name points to. Otherwise, use the static |
| 252 | * @kobj->name array. |
| 253 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | int kobject_set_name(struct kobject * kobj, const char * fmt, ...) |
| 255 | { |
| 256 | int error = 0; |
| 257 | int limit = KOBJ_NAME_LEN; |
| 258 | int need; |
| 259 | va_list args; |
| 260 | char * name; |
| 261 | |
| 262 | /* |
| 263 | * First, try the static array |
| 264 | */ |
| 265 | va_start(args,fmt); |
| 266 | need = vsnprintf(kobj->name,limit,fmt,args); |
| 267 | va_end(args); |
| 268 | if (need < limit) |
| 269 | name = kobj->name; |
| 270 | else { |
| 271 | /* |
| 272 | * Need more space? Allocate it and try again |
| 273 | */ |
| 274 | limit = need + 1; |
| 275 | name = kmalloc(limit,GFP_KERNEL); |
| 276 | if (!name) { |
| 277 | error = -ENOMEM; |
| 278 | goto Done; |
| 279 | } |
| 280 | va_start(args,fmt); |
| 281 | need = vsnprintf(name,limit,fmt,args); |
| 282 | va_end(args); |
| 283 | |
| 284 | /* Still? Give up. */ |
| 285 | if (need >= limit) { |
| 286 | kfree(name); |
| 287 | error = -EFAULT; |
| 288 | goto Done; |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | /* Free the old name, if necessary. */ |
| 293 | if (kobj->k_name && kobj->k_name != kobj->name) |
| 294 | kfree(kobj->k_name); |
| 295 | |
| 296 | /* Now, set the new name */ |
| 297 | kobj->k_name = name; |
| 298 | Done: |
| 299 | return error; |
| 300 | } |
| 301 | |
| 302 | EXPORT_SYMBOL(kobject_set_name); |
| 303 | |
| 304 | |
| 305 | /** |
| 306 | * kobject_rename - change the name of an object |
| 307 | * @kobj: object in question. |
| 308 | * @new_name: object's new name |
| 309 | */ |
| 310 | |
Dmitry Torokhov | f3b4f3c | 2005-04-26 02:32:00 -0500 | [diff] [blame] | 311 | int kobject_rename(struct kobject * kobj, const char *new_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | { |
| 313 | int error = 0; |
| 314 | |
| 315 | kobj = kobject_get(kobj); |
| 316 | if (!kobj) |
| 317 | return -EINVAL; |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 318 | if (!kobj->parent) |
| 319 | return -EINVAL; |
| 320 | error = sysfs_rename_dir(kobj, kobj->parent->dentry, new_name); |
| 321 | kobject_put(kobj); |
| 322 | |
| 323 | return error; |
| 324 | } |
| 325 | |
| 326 | /** |
| 327 | * kobject_rename - change the name of an object |
| 328 | * @kobj: object in question. |
Randy Dunlap | f95d882 | 2007-02-10 14:41:56 -0800 | [diff] [blame^] | 329 | * @new_parent: object's new parent |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 330 | * @new_name: object's new name |
| 331 | */ |
| 332 | |
| 333 | int kobject_shadow_rename(struct kobject * kobj, struct dentry *new_parent, |
| 334 | const char *new_name) |
| 335 | { |
| 336 | int error = 0; |
| 337 | |
| 338 | kobj = kobject_get(kobj); |
| 339 | if (!kobj) |
| 340 | return -EINVAL; |
| 341 | error = sysfs_rename_dir(kobj, new_parent, new_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | kobject_put(kobj); |
| 343 | |
| 344 | return error; |
| 345 | } |
| 346 | |
| 347 | /** |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 348 | * kobject_move - move object to another parent |
| 349 | * @kobj: object in question. |
Cornelia Huck | c744aea | 2007-01-08 20:16:44 +0100 | [diff] [blame] | 350 | * @new_parent: object's new parent (can be NULL) |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 351 | */ |
| 352 | |
| 353 | int kobject_move(struct kobject *kobj, struct kobject *new_parent) |
| 354 | { |
| 355 | int error; |
| 356 | struct kobject *old_parent; |
| 357 | const char *devpath = NULL; |
| 358 | char *devpath_string = NULL; |
| 359 | char *envp[2]; |
| 360 | |
| 361 | kobj = kobject_get(kobj); |
| 362 | if (!kobj) |
| 363 | return -EINVAL; |
| 364 | new_parent = kobject_get(new_parent); |
| 365 | if (!new_parent) { |
Cornelia Huck | c744aea | 2007-01-08 20:16:44 +0100 | [diff] [blame] | 366 | if (kobj->kset) |
| 367 | new_parent = kobject_get(&kobj->kset->kobj); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 368 | } |
| 369 | /* old object path */ |
| 370 | devpath = kobject_get_path(kobj, GFP_KERNEL); |
| 371 | if (!devpath) { |
| 372 | error = -ENOMEM; |
| 373 | goto out; |
| 374 | } |
| 375 | devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL); |
| 376 | if (!devpath_string) { |
| 377 | error = -ENOMEM; |
| 378 | goto out; |
| 379 | } |
| 380 | sprintf(devpath_string, "DEVPATH_OLD=%s", devpath); |
| 381 | envp[0] = devpath_string; |
| 382 | envp[1] = NULL; |
| 383 | error = sysfs_move_dir(kobj, new_parent); |
| 384 | if (error) |
| 385 | goto out; |
| 386 | old_parent = kobj->parent; |
| 387 | kobj->parent = new_parent; |
| 388 | kobject_put(old_parent); |
| 389 | kobject_uevent_env(kobj, KOBJ_MOVE, envp); |
| 390 | out: |
| 391 | kobject_put(kobj); |
| 392 | kfree(devpath_string); |
| 393 | kfree(devpath); |
| 394 | return error; |
| 395 | } |
| 396 | |
| 397 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | * kobject_del - unlink kobject from hierarchy. |
| 399 | * @kobj: object. |
| 400 | */ |
| 401 | |
| 402 | void kobject_del(struct kobject * kobj) |
| 403 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 404 | if (!kobj) |
| 405 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | sysfs_remove_dir(kobj); |
| 407 | unlink(kobj); |
| 408 | } |
| 409 | |
| 410 | /** |
| 411 | * kobject_unregister - remove object from hierarchy and decrement refcount. |
| 412 | * @kobj: object going away. |
| 413 | */ |
| 414 | |
| 415 | void kobject_unregister(struct kobject * kobj) |
| 416 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 417 | if (!kobj) |
| 418 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | pr_debug("kobject %s: unregistering\n",kobject_name(kobj)); |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 420 | kobject_uevent(kobj, KOBJ_REMOVE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | kobject_del(kobj); |
| 422 | kobject_put(kobj); |
| 423 | } |
| 424 | |
| 425 | /** |
| 426 | * kobject_get - increment refcount for object. |
| 427 | * @kobj: object. |
| 428 | */ |
| 429 | |
| 430 | struct kobject * kobject_get(struct kobject * kobj) |
| 431 | { |
| 432 | if (kobj) |
| 433 | kref_get(&kobj->kref); |
| 434 | return kobj; |
| 435 | } |
| 436 | |
| 437 | /** |
| 438 | * kobject_cleanup - free kobject resources. |
| 439 | * @kobj: object. |
| 440 | */ |
| 441 | |
| 442 | void kobject_cleanup(struct kobject * kobj) |
| 443 | { |
| 444 | struct kobj_type * t = get_ktype(kobj); |
| 445 | struct kset * s = kobj->kset; |
| 446 | struct kobject * parent = kobj->parent; |
| 447 | |
| 448 | pr_debug("kobject %s: cleaning up\n",kobject_name(kobj)); |
| 449 | if (kobj->k_name != kobj->name) |
| 450 | kfree(kobj->k_name); |
| 451 | kobj->k_name = NULL; |
| 452 | if (t && t->release) |
| 453 | t->release(kobj); |
| 454 | if (s) |
| 455 | kset_put(s); |
Mariusz Kozlowski | b067db4 | 2007-01-02 13:44:44 +0100 | [diff] [blame] | 456 | kobject_put(parent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | } |
| 458 | |
| 459 | static void kobject_release(struct kref *kref) |
| 460 | { |
| 461 | kobject_cleanup(container_of(kref, struct kobject, kref)); |
| 462 | } |
| 463 | |
| 464 | /** |
| 465 | * kobject_put - decrement refcount for object. |
| 466 | * @kobj: object. |
| 467 | * |
| 468 | * Decrement the refcount, and if 0, call kobject_cleanup(). |
| 469 | */ |
| 470 | void kobject_put(struct kobject * kobj) |
| 471 | { |
| 472 | if (kobj) |
| 473 | kref_put(&kobj->kref, kobject_release); |
| 474 | } |
| 475 | |
| 476 | |
Jun'ichi Nomura | 7423172 | 2006-03-13 17:14:25 -0500 | [diff] [blame] | 477 | static void dir_release(struct kobject *kobj) |
| 478 | { |
| 479 | kfree(kobj); |
| 480 | } |
| 481 | |
| 482 | static struct kobj_type dir_ktype = { |
| 483 | .release = dir_release, |
| 484 | .sysfs_ops = NULL, |
| 485 | .default_attrs = NULL, |
| 486 | }; |
| 487 | |
| 488 | /** |
| 489 | * kobject_add_dir - add sub directory of object. |
| 490 | * @parent: object in which a directory is created. |
| 491 | * @name: directory name. |
| 492 | * |
| 493 | * Add a plain directory object as child of given object. |
| 494 | */ |
| 495 | struct kobject *kobject_add_dir(struct kobject *parent, const char *name) |
| 496 | { |
| 497 | struct kobject *k; |
Randy Dunlap | 1018801 | 2006-07-11 20:49:41 -0700 | [diff] [blame] | 498 | int ret; |
Jun'ichi Nomura | 7423172 | 2006-03-13 17:14:25 -0500 | [diff] [blame] | 499 | |
| 500 | if (!parent) |
| 501 | return NULL; |
| 502 | |
| 503 | k = kzalloc(sizeof(*k), GFP_KERNEL); |
| 504 | if (!k) |
| 505 | return NULL; |
| 506 | |
| 507 | k->parent = parent; |
| 508 | k->ktype = &dir_ktype; |
| 509 | kobject_set_name(k, name); |
Randy Dunlap | 1018801 | 2006-07-11 20:49:41 -0700 | [diff] [blame] | 510 | ret = kobject_register(k); |
| 511 | if (ret < 0) { |
| 512 | printk(KERN_WARNING "kobject_add_dir: " |
| 513 | "kobject_register error: %d\n", ret); |
| 514 | kobject_del(k); |
| 515 | return NULL; |
| 516 | } |
Jun'ichi Nomura | 7423172 | 2006-03-13 17:14:25 -0500 | [diff] [blame] | 517 | |
| 518 | return k; |
| 519 | } |
Jun'ichi Nomura | 7423172 | 2006-03-13 17:14:25 -0500 | [diff] [blame] | 520 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | /** |
| 522 | * kset_init - initialize a kset for use |
| 523 | * @k: kset |
| 524 | */ |
| 525 | |
| 526 | void kset_init(struct kset * k) |
| 527 | { |
| 528 | kobject_init(&k->kobj); |
| 529 | INIT_LIST_HEAD(&k->list); |
| 530 | spin_lock_init(&k->list_lock); |
| 531 | } |
| 532 | |
| 533 | |
| 534 | /** |
| 535 | * kset_add - add a kset object to the hierarchy. |
| 536 | * @k: kset. |
| 537 | * |
| 538 | * Simply, this adds the kset's embedded kobject to the |
| 539 | * hierarchy. |
| 540 | * We also try to make sure that the kset's embedded kobject |
| 541 | * has a parent before it is added. We only care if the embedded |
| 542 | * kobject is not part of a kset itself, since kobject_add() |
| 543 | * assigns a parent in that case. |
| 544 | * If that is the case, and the kset has a controlling subsystem, |
| 545 | * then we set the kset's parent to be said subsystem. |
| 546 | */ |
| 547 | |
| 548 | int kset_add(struct kset * k) |
| 549 | { |
| 550 | if (!k->kobj.parent && !k->kobj.kset && k->subsys) |
| 551 | k->kobj.parent = &k->subsys->kset.kobj; |
| 552 | |
| 553 | return kobject_add(&k->kobj); |
| 554 | } |
| 555 | |
| 556 | |
| 557 | /** |
| 558 | * kset_register - initialize and add a kset. |
| 559 | * @k: kset. |
| 560 | */ |
| 561 | |
| 562 | int kset_register(struct kset * k) |
| 563 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 564 | if (!k) |
| 565 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | kset_init(k); |
| 567 | return kset_add(k); |
| 568 | } |
| 569 | |
| 570 | |
| 571 | /** |
| 572 | * kset_unregister - remove a kset. |
| 573 | * @k: kset. |
| 574 | */ |
| 575 | |
| 576 | void kset_unregister(struct kset * k) |
| 577 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 578 | if (!k) |
| 579 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | kobject_unregister(&k->kobj); |
| 581 | } |
| 582 | |
| 583 | |
| 584 | /** |
| 585 | * kset_find_obj - search for object in kset. |
| 586 | * @kset: kset we're looking in. |
| 587 | * @name: object's name. |
| 588 | * |
| 589 | * Lock kset via @kset->subsys, and iterate over @kset->list, |
| 590 | * looking for a matching kobject. If matching object is found |
| 591 | * take a reference and return the object. |
| 592 | */ |
| 593 | |
| 594 | struct kobject * kset_find_obj(struct kset * kset, const char * name) |
| 595 | { |
| 596 | struct list_head * entry; |
| 597 | struct kobject * ret = NULL; |
| 598 | |
| 599 | spin_lock(&kset->list_lock); |
| 600 | list_for_each(entry,&kset->list) { |
| 601 | struct kobject * k = to_kobj(entry); |
| 602 | if (kobject_name(k) && !strcmp(kobject_name(k),name)) { |
| 603 | ret = kobject_get(k); |
| 604 | break; |
| 605 | } |
| 606 | } |
| 607 | spin_unlock(&kset->list_lock); |
| 608 | return ret; |
| 609 | } |
| 610 | |
| 611 | |
| 612 | void subsystem_init(struct subsystem * s) |
| 613 | { |
| 614 | init_rwsem(&s->rwsem); |
| 615 | kset_init(&s->kset); |
| 616 | } |
| 617 | |
| 618 | /** |
| 619 | * subsystem_register - register a subsystem. |
| 620 | * @s: the subsystem we're registering. |
| 621 | * |
| 622 | * Once we register the subsystem, we want to make sure that |
| 623 | * the kset points back to this subsystem for correct usage of |
| 624 | * the rwsem. |
| 625 | */ |
| 626 | |
| 627 | int subsystem_register(struct subsystem * s) |
| 628 | { |
| 629 | int error; |
| 630 | |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 631 | if (!s) |
| 632 | return -EINVAL; |
| 633 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | subsystem_init(s); |
| 635 | pr_debug("subsystem %s: registering\n",s->kset.kobj.name); |
| 636 | |
| 637 | if (!(error = kset_add(&s->kset))) { |
| 638 | if (!s->kset.subsys) |
| 639 | s->kset.subsys = s; |
| 640 | } |
| 641 | return error; |
| 642 | } |
| 643 | |
| 644 | void subsystem_unregister(struct subsystem * s) |
| 645 | { |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 646 | if (!s) |
| 647 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | pr_debug("subsystem %s: unregistering\n",s->kset.kobj.name); |
| 649 | kset_unregister(&s->kset); |
| 650 | } |
| 651 | |
| 652 | |
| 653 | /** |
| 654 | * subsystem_create_file - export sysfs attribute file. |
| 655 | * @s: subsystem. |
| 656 | * @a: subsystem attribute descriptor. |
| 657 | */ |
| 658 | |
| 659 | int subsys_create_file(struct subsystem * s, struct subsys_attribute * a) |
| 660 | { |
| 661 | int error = 0; |
Greg Kroah-Hartman | 31b9025 | 2007-01-18 12:23:51 -0800 | [diff] [blame] | 662 | |
| 663 | if (!s || !a) |
| 664 | return -EINVAL; |
| 665 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | if (subsys_get(s)) { |
| 667 | error = sysfs_create_file(&s->kset.kobj,&a->attr); |
| 668 | subsys_put(s); |
| 669 | } |
| 670 | return error; |
| 671 | } |
| 672 | |
| 673 | |
| 674 | /** |
| 675 | * subsystem_remove_file - remove sysfs attribute file. |
| 676 | * @s: subsystem. |
| 677 | * @a: attribute desciptor. |
| 678 | */ |
Adrian Bunk | 5b3ef14 | 2006-04-22 12:14:44 +0200 | [diff] [blame] | 679 | #if 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | void subsys_remove_file(struct subsystem * s, struct subsys_attribute * a) |
| 681 | { |
| 682 | if (subsys_get(s)) { |
| 683 | sysfs_remove_file(&s->kset.kobj,&a->attr); |
| 684 | subsys_put(s); |
| 685 | } |
| 686 | } |
Adrian Bunk | 5b3ef14 | 2006-04-22 12:14:44 +0200 | [diff] [blame] | 687 | #endif /* 0 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 688 | |
| 689 | EXPORT_SYMBOL(kobject_init); |
| 690 | EXPORT_SYMBOL(kobject_register); |
| 691 | EXPORT_SYMBOL(kobject_unregister); |
| 692 | EXPORT_SYMBOL(kobject_get); |
| 693 | EXPORT_SYMBOL(kobject_put); |
| 694 | EXPORT_SYMBOL(kobject_add); |
| 695 | EXPORT_SYMBOL(kobject_del); |
| 696 | |
| 697 | EXPORT_SYMBOL(kset_register); |
| 698 | EXPORT_SYMBOL(kset_unregister); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | EXPORT_SYMBOL(subsystem_register); |
| 701 | EXPORT_SYMBOL(subsystem_unregister); |
| 702 | EXPORT_SYMBOL(subsys_create_file); |