1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * dir.c - Operations for configfs directories.
39  * subsys->su_mutex is held.
48 	struct configfs_dirent *sd = dentry->d_fsdata;  in configfs_d_iput()
54 		 * Set sd->s_dentry to null only when this dentry is the one  in configfs_d_iput()
56 		 * run just after configfs_lookup and set sd->s_dentry to  in configfs_d_iput()
59 		if (sd->s_dentry == dentry)  in configfs_d_iput()
60 			sd->s_dentry = NULL;  in configfs_d_iput()
75  * Helpers to make lockdep happy with our recursive locking of default groups'
77  * We put default groups i_mutexes in separate classes according to their depth
78  * from the youngest non-default group ancestor.
80  * For a non-default group A having default groups A/B, A/C, and A/C/D, default
82  * default_group_class[0], and default group A/C/D will be in
87  * The s_depth value is initialized to -1, adjusted to >= 0 when attaching
88  * default groups, and reset to -1 when all default groups are attached. During
90  * inode's mutex is set to default_group_class[s_depth - 1].
95 	sd->s_depth = -1;  in configfs_init_dirent_depth()
101 	int parent_depth = parent_sd->s_depth;  in configfs_set_dir_dirent_depth()
104 		sd->s_depth = parent_depth + 1;  in configfs_set_dir_dirent_depth()
112 	 * used to set new sub-directories s_depth, which is always done  in configfs_adjust_dir_dirent_depth_before_populate()
116 	 *  sd->s_depth == -1 iff we are a non default group.  in configfs_adjust_dir_dirent_depth_before_populate()
117 	 *  else (we are a default group) sd->s_depth > 0 (see  in configfs_adjust_dir_dirent_depth_before_populate()
120 	if (sd->s_depth == -1)  in configfs_adjust_dir_dirent_depth_before_populate()
122 		 * We are a non default group and we are going to create  in configfs_adjust_dir_dirent_depth_before_populate()
123 		 * default groups.  in configfs_adjust_dir_dirent_depth_before_populate()
125 		sd->s_depth = 0;  in configfs_adjust_dir_dirent_depth_before_populate()
131 	/* We will not create default groups anymore. */  in configfs_adjust_dir_dirent_depth_after_populate()
132 	sd->s_depth = -1;  in configfs_adjust_dir_dirent_depth_after_populate()
164 		atomic_set(&p->frag_count, 1);  in new_fragment()
165 		init_rwsem(&p->frag_sem);  in new_fragment()
166 		p->frag_dead = false;  in new_fragment()
173 	if (frag && atomic_dec_and_test(&frag->frag_count))  in put_fragment()
180 		atomic_inc(&frag->frag_count);  in get_fragment()
195 		return ERR_PTR(-ENOMEM);  in configfs_new_dirent()
197 	atomic_set(&sd->s_count, 1);  in configfs_new_dirent()
198 	INIT_LIST_HEAD(&sd->s_children);  in configfs_new_dirent()
199 	sd->s_element = element;  in configfs_new_dirent()
200 	sd->s_type = type;  in configfs_new_dirent()
203 	if (parent_sd->s_type & CONFIGFS_USET_DROPPING) {  in configfs_new_dirent()
206 		return ERR_PTR(-ENOENT);  in configfs_new_dirent()
208 	sd->s_frag = get_fragment(frag);  in configfs_new_dirent()
216 	if (sd->s_type & CONFIGFS_PINNED)  in configfs_new_dirent()
217 		list_add_tail(&sd->s_sibling, &parent_sd->s_children);  in configfs_new_dirent()
219 		list_add(&sd->s_sibling, &parent_sd->s_children);  in configfs_new_dirent()
227  * Return -EEXIST if there is already a configfs element with the same
234 	struct configfs_dirent *parent_sd = dentry->d_parent->d_fsdata;  in configfs_dirent_exists()
235 	const unsigned char *new = dentry->d_name.name;  in configfs_dirent_exists()
238 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {  in configfs_dirent_exists()
239 		if (sd->s_element) {  in configfs_dirent_exists()
244 				return -EEXIST;  in configfs_dirent_exists()
262 	sd->s_mode = mode;  in configfs_make_dirent()
263 	sd->s_dentry = dentry;  in configfs_make_dirent()
265 		dentry->d_fsdata = configfs_get(sd);  in configfs_make_dirent()
272 	struct configfs_dirent *sd = dentry->d_fsdata;  in configfs_remove_dirent()
277 	list_del_init(&sd->s_sibling);  in configfs_remove_dirent()
283  *	configfs_create_dir - create a directory for an config_item.
288  *	Note: user-created entries won't be allowed under this new directory
297 	struct dentry *p = dentry->d_parent;  in configfs_create_dir()
302 	error = configfs_make_dirent(p->d_fsdata, dentry, item, mode,  in configfs_create_dir()
308 	configfs_set_dir_dirent_depth(p->d_fsdata, dentry->d_fsdata);  in configfs_create_dir()
313 	inode->i_op = &configfs_dir_inode_operations;  in configfs_create_dir()
314 	inode->i_fop = &configfs_dir_operations;  in configfs_create_dir()
321 	item->ci_dentry = dentry;  in configfs_create_dir()
325 	configfs_put(dentry->d_fsdata);  in configfs_create_dir()
341 	sd->s_type &= ~CONFIGFS_USET_CREATING;  in configfs_dir_set_ready()
342 	list_for_each_entry(child_sd, &sd->s_children, s_sibling)  in configfs_dir_set_ready()
343 		if (child_sd->s_type & CONFIGFS_USET_CREATING)  in configfs_dir_set_ready()
352  * @return	non-zero iff the directory was validated
362 	ret = !(sd->s_type & CONFIGFS_USET_CREATING);  in configfs_dirent_is_ready()
373 	struct configfs_dirent *p = parent->d_fsdata;  in configfs_create_link()
377 			p->s_frag);  in configfs_create_link()
385 	inode->i_link = body;  in configfs_create_link()
386 	inode->i_op = &configfs_symlink_inode_operations;  in configfs_create_link()
392 	configfs_put(dentry->d_fsdata);  in configfs_create_link()
399 	struct dentry * parent = dget(d->d_parent);  in remove_dir()
412  * configfs_remove_dir - remove an config_item's directory.
424 	struct dentry * dentry = dget(item->ci_dentry);  in configfs_remove_dir()
440 	struct configfs_dirent * parent_sd = dentry->d_parent->d_fsdata;  in configfs_lookup()
444 	if (dentry->d_name.len > NAME_MAX)  in configfs_lookup()
445 		return ERR_PTR(-ENAMETOOLONG);  in configfs_lookup()
448 	 * Fake invisibility if dir belongs to a group/default groups hierarchy  in configfs_lookup()
456 		return ERR_PTR(-ENOENT);  in configfs_lookup()
459 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {  in configfs_lookup()
465 		if (sd->s_type & CONFIGFS_PINNED)  in configfs_lookup()
472 		if ((sd->s_type & CONFIGFS_NOT_PINNED) &&  in configfs_lookup()
473 		    !strcmp(configfs_get_name(sd), dentry->d_name.name)) {  in configfs_lookup()
474 			struct configfs_attribute *attr = sd->s_element;  in configfs_lookup()
475 			umode_t mode = (attr->ca_mode & S_IALLUGO) | S_IFREG;  in configfs_lookup()
477 			dentry->d_fsdata = configfs_get(sd);  in configfs_lookup()
478 			sd->s_dentry = dentry;  in configfs_lookup()
486 			if (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) {  in configfs_lookup()
487 				inode->i_size = 0;  in configfs_lookup()
488 				inode->i_fop = &configfs_bin_file_operations;  in configfs_lookup()
490 				inode->i_size = PAGE_SIZE;  in configfs_lookup()
491 				inode->i_fop = &configfs_file_operations;  in configfs_lookup()
506  * default detach.
512 	struct configfs_dirent *parent_sd = dentry->d_fsdata;  in configfs_detach_prep()
516 	/* Mark that we're trying to drop the group */  in configfs_detach_prep()
517 	parent_sd->s_type |= CONFIGFS_USET_DROPPING;  in configfs_detach_prep()
519 	ret = -EBUSY;  in configfs_detach_prep()
520 	if (parent_sd->s_links)  in configfs_detach_prep()
524 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {  in configfs_detach_prep()
525 		if (!sd->s_element ||  in configfs_detach_prep()
526 		    (sd->s_type & CONFIGFS_NOT_PINNED))  in configfs_detach_prep()
528 		if (sd->s_type & CONFIGFS_USET_DEFAULT) {  in configfs_detach_prep()
530 			if (sd->s_type & CONFIGFS_USET_IN_MKDIR) {  in configfs_detach_prep()
532 					*wait= dget(sd->s_dentry);  in configfs_detach_prep()
533 				return -EAGAIN;  in configfs_detach_prep()
540 			ret = configfs_detach_prep(sd->s_dentry, wait);  in configfs_detach_prep()
544 			ret = -ENOTEMPTY;  in configfs_detach_prep()
559 	struct configfs_dirent *parent_sd = dentry->d_fsdata;  in configfs_detach_rollback()
562 	parent_sd->s_type &= ~CONFIGFS_USET_DROPPING;  in configfs_detach_rollback()
564 	list_for_each_entry(sd, &parent_sd->s_children, s_sibling)  in configfs_detach_rollback()
565 		if (sd->s_type & CONFIGFS_USET_DEFAULT)  in configfs_detach_rollback()
566 			configfs_detach_rollback(sd->s_dentry);  in configfs_detach_rollback()
571 	struct dentry * dentry = dget(item->ci_dentry);  in detach_attrs()
579 		 dentry->d_name.name);  in detach_attrs()
581 	parent_sd = dentry->d_fsdata;  in detach_attrs()
582 	list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {  in detach_attrs()
583 		if (!sd->s_element || !(sd->s_type & CONFIGFS_NOT_PINNED))  in detach_attrs()
586 		list_del_init(&sd->s_sibling);  in detach_attrs()
600 	const struct config_item_type *t = item->ci_type;  in populate_attrs()
608 		return -EINVAL;  in populate_attrs()
610 	ops = t->ct_group_ops;  in populate_attrs()
612 	if (t->ct_attrs) {  in populate_attrs()
613 		for (i = 0; (attr = t->ct_attrs[i]) != NULL; i++) {  in populate_attrs()
614 			if (ops && ops->is_visible && !ops->is_visible(item, attr, i))  in populate_attrs()
621 	if (!error && t->ct_bin_attrs) {  in populate_attrs()
622 		for (i = 0; (bin_attr = t->ct_bin_attrs[i]) != NULL; i++) {  in populate_attrs()
623 			if (ops && ops->is_bin_visible && !ops->is_bin_visible(item, bin_attr, i))  in populate_attrs()
644 static void detach_groups(struct config_group *group)  in detach_groups()  argument
646 	struct dentry * dentry = dget(group->cg_item.ci_dentry);  in detach_groups()
654 	parent_sd = dentry->d_fsdata;  in detach_groups()
655 	list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {  in detach_groups()
656 		if (!sd->s_element ||  in detach_groups()
657 		    !(sd->s_type & CONFIGFS_USET_DEFAULT))  in detach_groups()
660 		child = sd->s_dentry;  in detach_groups()
664 		configfs_detach_group(sd->s_element);  in detach_groups()
665 		d_inode(child)->i_flags |= S_DEAD;  in detach_groups()
683  * on the sd->s_type.
685  * We could, perhaps, tweak our parent's ->mkdir for a minute and
689 				struct config_group *group,  in create_default_group()  argument
695 	struct dentry *child, *parent = parent_group->cg_item.ci_dentry;  in create_default_group()
697 	if (!group->cg_item.ci_name)  in create_default_group()
698 		group->cg_item.ci_name = group->cg_item.ci_namebuf;  in create_default_group()
700 	ret = -ENOMEM;  in create_default_group()
701 	child = d_alloc_name(parent, group->cg_item.ci_name);  in create_default_group()
705 		ret = configfs_attach_group(&parent_group->cg_item,  in create_default_group()
706 					    &group->cg_item, child, frag);  in create_default_group()
708 			sd = child->d_fsdata;  in create_default_group()
709 			sd->s_type |= CONFIGFS_USET_DEFAULT;  in create_default_group()
720 static int populate_groups(struct config_group *group,  in populate_groups()  argument
726 	list_for_each_entry(new_group, &group->default_groups, group_entry) {  in populate_groups()
727 		ret = create_default_group(group, new_group, frag);  in populate_groups()
729 			detach_groups(group);  in populate_groups()
737 void configfs_remove_default_groups(struct config_group *group)  in configfs_remove_default_groups()  argument
741 	list_for_each_entry_safe(g, n, &group->default_groups, group_entry) {  in configfs_remove_default_groups()
742 		list_del(&g->group_entry);  in configfs_remove_default_groups()
743 		config_item_put(&g->cg_item);  in configfs_remove_default_groups()
750  * subsys->su_mutex is held.
755 	struct config_group *group;  in unlink_obj()  local
757 	group = item->ci_group;  in unlink_obj()
758 	if (group) {  in unlink_obj()
759 		list_del_init(&item->ci_entry);  in unlink_obj()
761 		item->ci_group = NULL;  in unlink_obj()
762 		item->ci_parent = NULL;  in unlink_obj()
768 		config_group_put(group);  in unlink_obj()
775 	 * Parent seems redundant with group, but it makes certain  in link_obj()
778 	item->ci_parent = parent_item;  in link_obj()
784 	item->ci_group = config_group_get(to_config_group(parent_item));  in link_obj()
785 	list_add_tail(&item->ci_entry, &item->ci_group->cg_children);  in link_obj()
794 static void unlink_group(struct config_group *group)  in unlink_group()  argument
798 	list_for_each_entry(new_group, &group->default_groups, group_entry)  in unlink_group()
801 	group->cg_subsys = NULL;  in unlink_group()
802 	unlink_obj(&group->cg_item);  in unlink_group()
805 static void link_group(struct config_group *parent_group, struct config_group *group)  in link_group()  argument
810 	link_obj(&parent_group->cg_item, &group->cg_item);  in link_group()
812 	if (parent_group->cg_subsys)  in link_group()
813 		subsys = parent_group->cg_subsys;  in link_group()
814 	else if (configfs_is_root(&parent_group->cg_item))  in link_group()
815 		subsys = to_configfs_subsystem(group);  in link_group()
818 	group->cg_subsys = subsys;  in link_group()
820 	list_for_each_entry(new_group, &group->default_groups, group_entry)  in link_group()
821 		link_group(group, new_group);  in link_group()
857 			d_inode(dentry)->i_flags |= S_DEAD;  in configfs_attach_item()
884 		sd = dentry->d_fsdata;  in configfs_attach_group()
885 		sd->s_type |= CONFIGFS_USET_DIR;  in configfs_attach_group()
889 		 * We must lock the group's inode to avoid races with the VFS  in configfs_attach_group()
901 			d_inode(dentry)->i_flags |= S_DEAD;  in configfs_attach_group()
913 /* Caller holds the mutex of the group's inode */
934 	type = parent_item->ci_type;  in client_disconnect_notify()
937 	if (type->ct_group_ops && type->ct_group_ops->disconnect_notify)  in client_disconnect_notify()
938 		type->ct_group_ops->disconnect_notify(to_config_group(parent_item),  in client_disconnect_notify()
953 	type = parent_item->ci_type;  in client_drop_item()
957 	 * If ->drop_item() exists, it is responsible for the  in client_drop_item()
960 	if (type->ct_group_ops && type->ct_group_ops->drop_item)  in client_drop_item()
961 		type->ct_group_ops->drop_item(to_config_group(parent_item),  in client_drop_item()
972 #define type_print(_type) if (sd->s_type & _type) pr_info("%*s %s\n", level, " ", #_type)  in configfs_dump_one()
990 	if (!(sd->s_type & (CONFIGFS_DIR|CONFIGFS_ROOT)))  in configfs_dump()
993 	list_for_each_entry(child_sd, &sd->s_children, s_sibling) {  in configfs_dump()
1020  * VFS->configfs path.  So it must take VFS locks to prevent the
1021  * VFS->configfs stuff (configfs_mkdir(), configfs_rmdir(), etc).  This is
1043  * Here we do a depth-first search of the dentry hierarchy looking for
1054  * If the target is not found, -ENOENT is bubbled up.
1059  * much on the stack, though, so folks that need this function - be careful
1068 	BUG_ON(!origin || !origin->d_fsdata);  in configfs_depend_prep()
1069 	sd = origin->d_fsdata;  in configfs_depend_prep()
1071 	if (sd->s_element == target)  /* Boo-yah */  in configfs_depend_prep()
1074 	list_for_each_entry(child_sd, &sd->s_children, s_sibling) {  in configfs_depend_prep()
1075 		if ((child_sd->s_type & CONFIGFS_DIR) &&  in configfs_depend_prep()
1076 		    !(child_sd->s_type & CONFIGFS_USET_DROPPING) &&  in configfs_depend_prep()
1077 		    !(child_sd->s_type & CONFIGFS_USET_CREATING)) {  in configfs_depend_prep()
1078 			ret = configfs_depend_prep(child_sd->s_dentry,  in configfs_depend_prep()
1081 				goto out;  /* Child path boo-yah */  in configfs_depend_prep()
1086 	ret = -ENOENT;  in configfs_depend_prep()
1108 	p = target->ci_dentry->d_fsdata;  in configfs_do_depend_item()
1109 	p->s_dependent_count += 1;  in configfs_do_depend_item()
1124 	list_for_each_entry(p, &root_sd->s_children, s_sibling) {  in configfs_find_subsys_dentry()
1125 		if (p->s_type & CONFIGFS_DIR &&  in configfs_find_subsys_dentry()
1126 		    p->s_element == subsys_item) {  in configfs_find_subsys_dentry()
1141 	struct config_item *s_item = &subsys->su_group.cg_item;  in configfs_depend_item()
1159 	subsys_sd = configfs_find_subsys_dentry(root->d_fsdata, s_item);  in configfs_depend_item()
1161 		ret = -ENOENT;  in configfs_depend_item()
1166 	ret = configfs_do_depend_item(subsys_sd->s_dentry, target);  in configfs_depend_item()
1196 	sd = target->ci_dentry->d_fsdata;  in configfs_undepend_item()
1197 	BUG_ON(sd->s_dependent_count < 1);  in configfs_undepend_item()
1199 	sd->s_dependent_count -= 1;  in configfs_undepend_item()
1224 	int ret = -ENOENT;  in configfs_depend_item_unlocked()
1228 		return -EINVAL;  in configfs_depend_item_unlocked()
1230 	parent = target->ci_group;  in configfs_depend_item_unlocked()
1235 	if (configfs_is_root(&parent->cg_item)) {  in configfs_depend_item_unlocked()
1239 		target_subsys = parent->cg_subsys;  in configfs_depend_item_unlocked()
1241 		for (root = parent; !configfs_is_root(&root->cg_item);  in configfs_depend_item_unlocked()
1242 		     root = root->cg_item.ci_group)  in configfs_depend_item_unlocked()
1252 		inode_lock(d_inode(root->cg_item.ci_dentry));  in configfs_depend_item_unlocked()
1259 				root->cg_item.ci_dentry->d_fsdata,  in configfs_depend_item_unlocked()
1260 				&target_subsys->su_group.cg_item);  in configfs_depend_item_unlocked()
1264 		subsys_sd = target_subsys->su_group.cg_item.ci_dentry->d_fsdata;  in configfs_depend_item_unlocked()
1268 	ret = configfs_do_depend_item(subsys_sd->s_dentry, target);  in configfs_depend_item_unlocked()
1276 		inode_unlock(d_inode(root->cg_item.ci_dentry));  in configfs_depend_item_unlocked()
1287 	struct config_group *group = NULL;  in configfs_mkdir()  local
1297 	sd = dentry->d_parent->d_fsdata;  in configfs_mkdir()
1300 	 * Fake invisibility if dir belongs to a group/default groups hierarchy  in configfs_mkdir()
1304 		ret = -ENOENT;  in configfs_mkdir()
1308 	if (!(sd->s_type & CONFIGFS_USET_DIR)) {  in configfs_mkdir()
1309 		ret = -EPERM;  in configfs_mkdir()
1315 		ret = -ENOMEM;  in configfs_mkdir()
1320 	parent_item = configfs_get_config_item(dentry->d_parent);  in configfs_mkdir()
1321 	type = parent_item->ci_type;  in configfs_mkdir()
1322 	subsys = to_config_group(parent_item)->cg_subsys;  in configfs_mkdir()
1325 	if (!type || !type->ct_group_ops ||  in configfs_mkdir()
1326 	    (!type->ct_group_ops->make_group &&  in configfs_mkdir()
1327 	     !type->ct_group_ops->make_item)) {  in configfs_mkdir()
1328 		ret = -EPERM;  /* Lack-of-mkdir returns -EPERM */  in configfs_mkdir()
1337 	if (!subsys->su_group.cg_item.ci_type) {  in configfs_mkdir()
1338 		ret = -EINVAL;  in configfs_mkdir()
1341 	subsys_owner = subsys->su_group.cg_item.ci_type->ct_owner;  in configfs_mkdir()
1343 		ret = -EINVAL;  in configfs_mkdir()
1347 	name = kmalloc(dentry->d_name.len + 1, GFP_KERNEL);  in configfs_mkdir()
1349 		ret = -ENOMEM;  in configfs_mkdir()
1353 	snprintf(name, dentry->d_name.len + 1, "%s", dentry->d_name.name);  in configfs_mkdir()
1355 	mutex_lock(&subsys->su_mutex);  in configfs_mkdir()
1356 	if (type->ct_group_ops->make_group) {  in configfs_mkdir()
1357 		group = type->ct_group_ops->make_group(to_config_group(parent_item), name);  in configfs_mkdir()
1358 		if (!group)  in configfs_mkdir()
1359 			group = ERR_PTR(-ENOMEM);  in configfs_mkdir()
1360 		if (!IS_ERR(group)) {  in configfs_mkdir()
1361 			link_group(to_config_group(parent_item), group);  in configfs_mkdir()
1362 			item = &group->cg_item;  in configfs_mkdir()
1364 			ret = PTR_ERR(group);  in configfs_mkdir()
1366 		item = type->ct_group_ops->make_item(to_config_group(parent_item), name);  in configfs_mkdir()
1368 			item = ERR_PTR(-ENOMEM);  in configfs_mkdir()
1374 	mutex_unlock(&subsys->su_mutex);  in configfs_mkdir()
1390 	type = item->ci_type;  in configfs_mkdir()
1392 		ret = -EINVAL;  in configfs_mkdir()
1396 	new_item_owner = type->ct_owner;  in configfs_mkdir()
1398 		ret = -EINVAL;  in configfs_mkdir()
1417 	sd->s_type |= CONFIGFS_USET_IN_MKDIR;  in configfs_mkdir()
1420 	if (group)  in configfs_mkdir()
1426 	sd->s_type &= ~CONFIGFS_USET_IN_MKDIR;  in configfs_mkdir()
1428 		configfs_dir_set_ready(dentry->d_fsdata);  in configfs_mkdir()
1434 		mutex_lock(&subsys->su_mutex);  in configfs_mkdir()
1437 		if (group)  in configfs_mkdir()
1438 			unlink_group(group);  in configfs_mkdir()
1443 		mutex_unlock(&subsys->su_mutex);  in configfs_mkdir()
1455 	 * link_obj()/link_group() took a reference from child->parent,  in configfs_mkdir()
1476 	sd = dentry->d_fsdata;  in configfs_rmdir()
1477 	if (sd->s_type & CONFIGFS_USET_DEFAULT)  in configfs_rmdir()
1478 		return -EPERM;  in configfs_rmdir()
1481 	parent_item = configfs_get_config_item(dentry->d_parent);  in configfs_rmdir()
1482 	subsys = to_config_group(parent_item)->cg_subsys;  in configfs_rmdir()
1485 	if (!parent_item->ci_type) {  in configfs_rmdir()
1487 		return -EINVAL;  in configfs_rmdir()
1491 	BUG_ON(!subsys->su_group.cg_item.ci_type);  in configfs_rmdir()
1492 	subsys_owner = subsys->su_group.cg_item.ci_type->ct_owner;  in configfs_rmdir()
1508 		ret = sd->s_dependent_count ? -EBUSY : 0;  in configfs_rmdir()
1518 			if (ret != -EAGAIN) {  in configfs_rmdir()
1528 	} while (ret == -EAGAIN);  in configfs_rmdir()
1530 	frag = sd->s_frag;  in configfs_rmdir()
1531 	if (down_write_killable(&frag->frag_sem)) {  in configfs_rmdir()
1536 		return -EINTR;  in configfs_rmdir()
1538 	frag->frag_dead = true;  in configfs_rmdir()
1539 	up_write(&frag->frag_sem);  in configfs_rmdir()
1547 	if (item->ci_type)  in configfs_rmdir()
1548 		dead_item_owner = item->ci_type->ct_owner;  in configfs_rmdir()
1550 	if (sd->s_type & CONFIGFS_USET_DIR) {  in configfs_rmdir()
1553 		mutex_lock(&subsys->su_mutex);  in configfs_rmdir()
1559 		mutex_lock(&subsys->su_mutex);  in configfs_rmdir()
1565 	mutex_unlock(&subsys->su_mutex);  in configfs_rmdir()
1592 	struct dentry * dentry = file->f_path.dentry;  in configfs_dir_open()
1593 	struct configfs_dirent * parent_sd = dentry->d_fsdata;  in configfs_dir_open()
1598 	 * Fake invisibility if dir belongs to a group/default groups hierarchy  in configfs_dir_open()
1601 	err = -ENOENT;  in configfs_dir_open()
1603 		file->private_data = configfs_new_dirent(parent_sd, NULL, 0, NULL);  in configfs_dir_open()
1604 		err = PTR_ERR_OR_ZERO(file->private_data);  in configfs_dir_open()
1613 	struct dentry * dentry = file->f_path.dentry;  in configfs_dir_close()
1614 	struct configfs_dirent * cursor = file->private_data;  in configfs_dir_close()
1618 	list_del_init(&cursor->s_sibling);  in configfs_dir_close()
1629 	struct dentry *dentry = file->f_path.dentry;  in configfs_readdir()
1630 	struct super_block *sb = dentry->d_sb;  in configfs_readdir()
1631 	struct configfs_dirent * parent_sd = dentry->d_fsdata;  in configfs_readdir()
1632 	struct configfs_dirent *cursor = file->private_data;  in configfs_readdir()
1633 	struct list_head *p, *q = &cursor->s_sibling;  in configfs_readdir()
1639 	if (ctx->pos == 2)  in configfs_readdir()
1640 		list_move(q, &parent_sd->s_children);  in configfs_readdir()
1641 	for (p = q->next; p != &parent_sd->s_children; p = p->next) {  in configfs_readdir()
1648 		if (!next->s_element)  in configfs_readdir()
1664 		dentry = next->s_dentry;  in configfs_readdir()
1668 			ino = inode->i_ino;  in configfs_readdir()
1677 			      fs_umode_to_dtype(next->s_mode)))  in configfs_readdir()
1683 		ctx->pos++;  in configfs_readdir()
1691 	struct dentry * dentry = file->f_path.dentry;  in configfs_dir_lseek()
1695 			offset += file->f_pos;  in configfs_dir_lseek()
1701 		default:  in configfs_dir_lseek()
1702 			return -EINVAL;  in configfs_dir_lseek()
1704 	if (offset != file->f_pos) {  in configfs_dir_lseek()
1705 		file->f_pos = offset;  in configfs_dir_lseek()
1706 		if (file->f_pos >= 2) {  in configfs_dir_lseek()
1707 			struct configfs_dirent *sd = dentry->d_fsdata;  in configfs_dir_lseek()
1708 			struct configfs_dirent *cursor = file->private_data;  in configfs_dir_lseek()
1710 			loff_t n = file->f_pos - 2;  in configfs_dir_lseek()
1713 			list_del(&cursor->s_sibling);  in configfs_dir_lseek()
1714 			p = sd->s_children.next;  in configfs_dir_lseek()
1715 			while (n && p != &sd->s_children) {  in configfs_dir_lseek()
1719 				if (next->s_element)  in configfs_dir_lseek()
1720 					n--;  in configfs_dir_lseek()
1721 				p = p->next;  in configfs_dir_lseek()
1723 			list_add_tail(&cursor->s_sibling, p);  in configfs_dir_lseek()
1739  * configfs_register_group - creates a parent-child relation between two groups
1740  * @parent_group:	parent group
1741  * @group:		child group
1749 			    struct config_group *group)  in configfs_register_group()  argument
1751 	struct configfs_subsystem *subsys = parent_group->cg_subsys;  in configfs_register_group()
1758 		return -ENOMEM;  in configfs_register_group()
1760 	mutex_lock(&subsys->su_mutex);  in configfs_register_group()
1761 	link_group(parent_group, group);  in configfs_register_group()
1762 	mutex_unlock(&subsys->su_mutex);  in configfs_register_group()
1764 	parent = parent_group->cg_item.ci_dentry;  in configfs_register_group()
1767 	ret = create_default_group(parent_group, group, frag);  in configfs_register_group()
1772 	configfs_dir_set_ready(group->cg_item.ci_dentry->d_fsdata);  in configfs_register_group()
1779 	mutex_lock(&subsys->su_mutex);  in configfs_register_group()
1780 	unlink_group(group);  in configfs_register_group()
1781 	mutex_unlock(&subsys->su_mutex);  in configfs_register_group()
1788  * configfs_unregister_group() - unregisters a child group from its parent
1789  * @group: parent group to be unregistered
1793 void configfs_unregister_group(struct config_group *group)  in configfs_unregister_group()  argument
1795 	struct configfs_subsystem *subsys = group->cg_subsys;  in configfs_unregister_group()
1796 	struct dentry *dentry = group->cg_item.ci_dentry;  in configfs_unregister_group()
1797 	struct dentry *parent = group->cg_item.ci_parent->ci_dentry;  in configfs_unregister_group()
1798 	struct configfs_dirent *sd = dentry->d_fsdata;  in configfs_unregister_group()
1799 	struct configfs_fragment *frag = sd->s_frag;  in configfs_unregister_group()
1801 	down_write(&frag->frag_sem);  in configfs_unregister_group()
1802 	frag->frag_dead = true;  in configfs_unregister_group()
1803 	up_write(&frag->frag_sem);  in configfs_unregister_group()
1810 	configfs_detach_group(&group->cg_item);  in configfs_unregister_group()
1811 	d_inode(dentry)->i_flags |= S_DEAD;  in configfs_unregister_group()
1819 	mutex_lock(&subsys->su_mutex);  in configfs_unregister_group()
1820 	unlink_group(group);  in configfs_unregister_group()
1821 	mutex_unlock(&subsys->su_mutex);  in configfs_unregister_group()
1826  * configfs_register_default_group() - allocates and registers a child group
1827  * @parent_group:	parent group
1828  * @name:		child group name
1831  * boilerplate to allocate and register a child group with its parent. We need
1834  * Return: allocated config group or ERR_PTR() on error
1842 	struct config_group *group;  in configfs_register_default_group()  local
1844 	group = kzalloc(sizeof(*group), GFP_KERNEL);  in configfs_register_default_group()
1845 	if (!group)  in configfs_register_default_group()
1846 		return ERR_PTR(-ENOMEM);  in configfs_register_default_group()
1847 	config_group_init_type_name(group, name, item_type);  in configfs_register_default_group()
1849 	ret = configfs_register_group(parent_group, group);  in configfs_register_default_group()
1851 		kfree(group);  in configfs_register_default_group()
1854 	return group;  in configfs_register_default_group()
1859  * configfs_unregister_default_group() - unregisters and frees a child group
1860  * @group:	the group to act on
1862 void configfs_unregister_default_group(struct config_group *group)  in configfs_unregister_default_group()  argument
1864 	configfs_unregister_group(group);  in configfs_unregister_default_group()
1865 	kfree(group);  in configfs_unregister_default_group()
1872 	struct config_group *group = &subsys->su_group;  in configfs_register_subsystem()  local
1880 		return -ENOMEM;  in configfs_register_subsystem()
1888 	if (!group->cg_item.ci_name)  in configfs_register_subsystem()
1889 		group->cg_item.ci_name = group->cg_item.ci_namebuf;  in configfs_register_subsystem()
1891 	sd = root->d_fsdata;  in configfs_register_subsystem()
1893 	link_group(to_config_group(sd->s_element), group);  in configfs_register_subsystem()
1898 	err = -ENOMEM;  in configfs_register_subsystem()
1899 	dentry = d_alloc_name(root, group->cg_item.ci_name);  in configfs_register_subsystem()
1905 			err = configfs_attach_group(sd->s_element,  in configfs_register_subsystem()
1906 						    &group->cg_item,  in configfs_register_subsystem()
1914 			configfs_dir_set_ready(dentry->d_fsdata);  in configfs_register_subsystem()
1923 		unlink_group(group);  in configfs_register_subsystem()
1934 	struct config_group *group = &subsys->su_group;  in configfs_unregister_subsystem()  local
1935 	struct dentry *dentry = group->cg_item.ci_dentry;  in configfs_unregister_subsystem()
1936 	struct dentry *root = dentry->d_sb->s_root;  in configfs_unregister_subsystem()
1937 	struct configfs_dirent *sd = dentry->d_fsdata;  in configfs_unregister_subsystem()
1938 	struct configfs_fragment *frag = sd->s_frag;  in configfs_unregister_subsystem()
1940 	if (dentry->d_parent != root) {  in configfs_unregister_subsystem()
1941 		pr_err("Tried to unregister non-subsystem!\n");  in configfs_unregister_subsystem()
1945 	down_write(&frag->frag_sem);  in configfs_unregister_subsystem()
1946 	frag->frag_dead = true;  in configfs_unregister_subsystem()
1947 	up_write(&frag->frag_sem);  in configfs_unregister_subsystem()
1955 		pr_err("Tried to unregister non-empty subsystem!\n");  in configfs_unregister_subsystem()
1959 	configfs_detach_group(&group->cg_item);  in configfs_unregister_subsystem()
1960 	d_inode(dentry)->i_flags |= S_DEAD;  in configfs_unregister_subsystem()
1972 	unlink_group(group);  in configfs_unregister_subsystem()