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Diffstat (limited to 'Documentation/filesystems/configfs/configfs_example_explicit.c')
| -rw-r--r-- | Documentation/filesystems/configfs/configfs_example_explicit.c | 483 |
1 files changed, 0 insertions, 483 deletions
diff --git a/Documentation/filesystems/configfs/configfs_example_explicit.c b/Documentation/filesystems/configfs/configfs_example_explicit.c deleted file mode 100644 index 1420233dfa55..000000000000 --- a/Documentation/filesystems/configfs/configfs_example_explicit.c +++ /dev/null @@ -1,483 +0,0 @@ -/* - * vim: noexpandtab ts=8 sts=0 sw=8: - * - * configfs_example_explicit.c - This file is a demonstration module - * containing a number of configfs subsystems. It explicitly defines - * each structure without using the helper macros defined in - * configfs.h. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 021110-1307, USA. - * - * Based on sysfs: - * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel - * - * configfs Copyright (C) 2005 Oracle. All rights reserved. - */ - -#include <linux/init.h> -#include <linux/module.h> -#include <linux/slab.h> - -#include <linux/configfs.h> - - - -/* - * 01-childless - * - * This first example is a childless subsystem. It cannot create - * any config_items. It just has attributes. - * - * Note that we are enclosing the configfs_subsystem inside a container. - * This is not necessary if a subsystem has no attributes directly - * on the subsystem. See the next example, 02-simple-children, for - * such a subsystem. - */ - -struct childless { - struct configfs_subsystem subsys; - int showme; - int storeme; -}; - -struct childless_attribute { - struct configfs_attribute attr; - ssize_t (*show)(struct childless *, char *); - ssize_t (*store)(struct childless *, const char *, size_t); -}; - -static inline struct childless *to_childless(struct config_item *item) -{ - return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL; -} - -static ssize_t childless_showme_read(struct childless *childless, - char *page) -{ - ssize_t pos; - - pos = sprintf(page, "%d\n", childless->showme); - childless->showme++; - - return pos; -} - -static ssize_t childless_storeme_read(struct childless *childless, - char *page) -{ - return sprintf(page, "%d\n", childless->storeme); -} - -static ssize_t childless_storeme_write(struct childless *childless, - const char *page, - size_t count) -{ - unsigned long tmp; - char *p = (char *) page; - - tmp = simple_strtoul(p, &p, 10); - if ((*p != '\0') && (*p != '\n')) - return -EINVAL; - - if (tmp > INT_MAX) - return -ERANGE; - - childless->storeme = tmp; - - return count; -} - -static ssize_t childless_description_read(struct childless *childless, - char *page) -{ - return sprintf(page, -"[01-childless]\n" -"\n" -"The childless subsystem is the simplest possible subsystem in\n" -"configfs. It does not support the creation of child config_items.\n" -"It only has a few attributes. In fact, it isn't much different\n" -"than a directory in /proc.\n"); -} - -static struct childless_attribute childless_attr_showme = { - .attr = { .ca_owner = THIS_MODULE, .ca_name = "showme", .ca_mode = S_IRUGO }, - .show = childless_showme_read, -}; -static struct childless_attribute childless_attr_storeme = { - .attr = { .ca_owner = THIS_MODULE, .ca_name = "storeme", .ca_mode = S_IRUGO | S_IWUSR }, - .show = childless_storeme_read, - .store = childless_storeme_write, -}; -static struct childless_attribute childless_attr_description = { - .attr = { .ca_owner = THIS_MODULE, .ca_name = "description", .ca_mode = S_IRUGO }, - .show = childless_description_read, -}; - -static struct configfs_attribute *childless_attrs[] = { - &childless_attr_showme.attr, - &childless_attr_storeme.attr, - &childless_attr_description.attr, - NULL, -}; - -static ssize_t childless_attr_show(struct config_item *item, - struct configfs_attribute *attr, - char *page) -{ - struct childless *childless = to_childless(item); - struct childless_attribute *childless_attr = - container_of(attr, struct childless_attribute, attr); - ssize_t ret = 0; - - if (childless_attr->show) - ret = childless_attr->show(childless, page); - return ret; -} - -static ssize_t childless_attr_store(struct config_item *item, - struct configfs_attribute *attr, - const char *page, size_t count) -{ - struct childless *childless = to_childless(item); - struct childless_attribute *childless_attr = - container_of(attr, struct childless_attribute, attr); - ssize_t ret = -EINVAL; - - if (childless_attr->store) - ret = childless_attr->store(childless, page, count); - return ret; -} - -static struct configfs_item_operations childless_item_ops = { - .show_attribute = childless_attr_show, - .store_attribute = childless_attr_store, -}; - -static struct config_item_type childless_type = { - .ct_item_ops = &childless_item_ops, - .ct_attrs = childless_attrs, - .ct_owner = THIS_MODULE, -}; - -static struct childless childless_subsys = { - .subsys = { - .su_group = { - .cg_item = { - .ci_namebuf = "01-childless", - .ci_type = &childless_type, - }, - }, - }, -}; - - -/* ----------------------------------------------------------------- */ - -/* - * 02-simple-children - * - * This example merely has a simple one-attribute child. Note that - * there is no extra attribute structure, as the child's attribute is - * known from the get-go. Also, there is no container for the - * subsystem, as it has no attributes of its own. - */ - -struct simple_child { - struct config_item item; - int storeme; -}; - -static inline struct simple_child *to_simple_child(struct config_item *item) -{ - return item ? container_of(item, struct simple_child, item) : NULL; -} - -static struct configfs_attribute simple_child_attr_storeme = { - .ca_owner = THIS_MODULE, - .ca_name = "storeme", - .ca_mode = S_IRUGO | S_IWUSR, -}; - -static struct configfs_attribute *simple_child_attrs[] = { - &simple_child_attr_storeme, - NULL, -}; - -static ssize_t simple_child_attr_show(struct config_item *item, - struct configfs_attribute *attr, - char *page) -{ - ssize_t count; - struct simple_child *simple_child = to_simple_child(item); - - count = sprintf(page, "%d\n", simple_child->storeme); - - return count; -} - -static ssize_t simple_child_attr_store(struct config_item *item, - struct configfs_attribute *attr, - const char *page, size_t count) -{ - struct simple_child *simple_child = to_simple_child(item); - unsigned long tmp; - char *p = (char *) page; - - tmp = simple_strtoul(p, &p, 10); - if (!p || (*p && (*p != '\n'))) - return -EINVAL; - - if (tmp > INT_MAX) - return -ERANGE; - - simple_child->storeme = tmp; - - return count; -} - -static void simple_child_release(struct config_item *item) -{ - kfree(to_simple_child(item)); -} - -static struct configfs_item_operations simple_child_item_ops = { - .release = simple_child_release, - .show_attribute = simple_child_attr_show, - .store_attribute = simple_child_attr_store, -}; - -static struct config_item_type simple_child_type = { - .ct_item_ops = &simple_child_item_ops, - .ct_attrs = simple_child_attrs, - .ct_owner = THIS_MODULE, -}; - - -struct simple_children { - struct config_group group; -}; - -static inline struct simple_children *to_simple_children(struct config_item *item) -{ - return item ? container_of(to_config_group(item), struct simple_children, group) : NULL; -} - -static struct config_item *simple_children_make_item(struct config_group *group, const char *name) -{ - struct simple_child *simple_child; - - simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL); - if (!simple_child) - return ERR_PTR(-ENOMEM); - - config_item_init_type_name(&simple_child->item, name, - &simple_child_type); - - simple_child->storeme = 0; - - return &simple_child->item; -} - -static struct configfs_attribute simple_children_attr_description = { - .ca_owner = THIS_MODULE, - .ca_name = "description", - .ca_mode = S_IRUGO, -}; - -static struct configfs_attribute *simple_children_attrs[] = { - &simple_children_attr_description, - NULL, -}; - -static ssize_t simple_children_attr_show(struct config_item *item, - struct configfs_attribute *attr, - char *page) -{ - return sprintf(page, -"[02-simple-children]\n" -"\n" -"This subsystem allows the creation of child config_items. These\n" -"items have only one attribute that is readable and writeable.\n"); -} - -static void simple_children_release(struct config_item *item) -{ - kfree(to_simple_children(item)); -} - -static struct configfs_item_operations simple_children_item_ops = { - .release = simple_children_release, - .show_attribute = simple_children_attr_show, -}; - -/* - * Note that, since no extra work is required on ->drop_item(), - * no ->drop_item() is provided. - */ -static struct configfs_group_operations simple_children_group_ops = { - .make_item = simple_children_make_item, -}; - -static struct config_item_type simple_children_type = { - .ct_item_ops = &simple_children_item_ops, - .ct_group_ops = &simple_children_group_ops, - .ct_attrs = simple_children_attrs, - .ct_owner = THIS_MODULE, -}; - -static struct configfs_subsystem simple_children_subsys = { - .su_group = { - .cg_item = { - .ci_namebuf = "02-simple-children", - .ci_type = &simple_children_type, - }, - }, -}; - - -/* ----------------------------------------------------------------- */ - -/* - * 03-group-children - * - * This example reuses the simple_children group from above. However, - * the simple_children group is not the subsystem itself, it is a - * child of the subsystem. Creation of a group in the subsystem creates - * a new simple_children group. That group can then have simple_child - * children of its own. - */ - -static struct config_group *group_children_make_group(struct config_group *group, const char *name) -{ - struct simple_children *simple_children; - - simple_children = kzalloc(sizeof(struct simple_children), - GFP_KERNEL); - if (!simple_children) - return ERR_PTR(-ENOMEM); - - config_group_init_type_name(&simple_children->group, name, - &simple_children_type); - - return &simple_children->group; -} - -static struct configfs_attribute group_children_attr_description = { - .ca_owner = THIS_MODULE, - .ca_name = "description", - .ca_mode = S_IRUGO, -}; - -static struct configfs_attribute *group_children_attrs[] = { - &group_children_attr_description, - NULL, -}; - -static ssize_t group_children_attr_show(struct config_item *item, - struct configfs_attribute *attr, - char *page) -{ - return sprintf(page, -"[03-group-children]\n" -"\n" -"This subsystem allows the creation of child config_groups. These\n" -"groups are like the subsystem simple-children.\n"); -} - -static struct configfs_item_operations group_children_item_ops = { - .show_attribute = group_children_attr_show, -}; - -/* - * Note that, since no extra work is required on ->drop_item(), - * no ->drop_item() is provided. - */ -static struct configfs_group_operations group_children_group_ops = { - .make_group = group_children_make_group, -}; - -static struct config_item_type group_children_type = { - .ct_item_ops = &group_children_item_ops, - .ct_group_ops = &group_children_group_ops, - .ct_attrs = group_children_attrs, - .ct_owner = THIS_MODULE, -}; - -static struct configfs_subsystem group_children_subsys = { - .su_group = { - .cg_item = { - .ci_namebuf = "03-group-children", - .ci_type = &group_children_type, - }, - }, -}; - -/* ----------------------------------------------------------------- */ - -/* - * We're now done with our subsystem definitions. - * For convenience in this module, here's a list of them all. It - * allows the init function to easily register them. Most modules - * will only have one subsystem, and will only call register_subsystem - * on it directly. - */ -static struct configfs_subsystem *example_subsys[] = { - &childless_subsys.subsys, - &simple_children_subsys, - &group_children_subsys, - NULL, -}; - -static int __init configfs_example_init(void) -{ - int ret; - int i; - struct configfs_subsystem *subsys; - - for (i = 0; example_subsys[i]; i++) { - subsys = example_subsys[i]; - - config_group_init(&subsys->su_group); - mutex_init(&subsys->su_mutex); - ret = configfs_register_subsystem(subsys); - if (ret) { - printk(KERN_ERR "Error %d while registering subsystem %s\n", - ret, - subsys->su_group.cg_item.ci_namebuf); - goto out_unregister; - } - } - - return 0; - -out_unregister: - for (i--; i >= 0; i--) - configfs_unregister_subsystem(example_subsys[i]); - - return ret; -} - -static void __exit configfs_example_exit(void) -{ - int i; - - for (i = 0; example_subsys[i]; i++) - configfs_unregister_subsystem(example_subsys[i]); -} - -module_init(configfs_example_init); -module_exit(configfs_example_exit); -MODULE_LICENSE("GPL"); |