+++ /dev/null
-/*
- * 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");
projects / firefly-linux-kernel-4.4.55.git / blobdiff