perf hists: Move sort__has_sym into struct perf_hpp_list
[linux/fpc-iii.git] / samples / configfs / configfs_sample.c
blob1ea33119e53272e09ee20e727e44ce21577d6ece
1 /*
2 * vim: noexpandtab ts=8 sts=0 sw=8:
4 * configfs_example_macros.c - This file is a demonstration module
5 * containing a number of configfs subsystems. It uses the helper
6 * macros defined by configfs.h
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public
19 * License along with this program; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 021110-1307, USA.
23 * Based on sysfs:
24 * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
26 * configfs Copyright (C) 2005 Oracle. All rights reserved.
29 #include <linux/init.h>
30 #include <linux/module.h>
31 #include <linux/slab.h>
33 #include <linux/configfs.h>
38 * 01-childless
40 * This first example is a childless subsystem. It cannot create
41 * any config_items. It just has attributes.
43 * Note that we are enclosing the configfs_subsystem inside a container.
44 * This is not necessary if a subsystem has no attributes directly
45 * on the subsystem. See the next example, 02-simple-children, for
46 * such a subsystem.
49 struct childless {
50 struct configfs_subsystem subsys;
51 int showme;
52 int storeme;
55 static inline struct childless *to_childless(struct config_item *item)
57 return item ? container_of(to_configfs_subsystem(to_config_group(item)),
58 struct childless, subsys) : NULL;
61 static ssize_t childless_showme_show(struct config_item *item, char *page)
63 struct childless *childless = to_childless(item);
64 ssize_t pos;
66 pos = sprintf(page, "%d\n", childless->showme);
67 childless->showme++;
69 return pos;
72 static ssize_t childless_storeme_show(struct config_item *item, char *page)
74 return sprintf(page, "%d\n", to_childless(item)->storeme);
77 static ssize_t childless_storeme_store(struct config_item *item,
78 const char *page, size_t count)
80 struct childless *childless = to_childless(item);
81 unsigned long tmp;
82 char *p = (char *) page;
84 tmp = simple_strtoul(p, &p, 10);
85 if (!p || (*p && (*p != '\n')))
86 return -EINVAL;
88 if (tmp > INT_MAX)
89 return -ERANGE;
91 childless->storeme = tmp;
93 return count;
96 static ssize_t childless_description_show(struct config_item *item, char *page)
98 return sprintf(page,
99 "[01-childless]\n"
100 "\n"
101 "The childless subsystem is the simplest possible subsystem in\n"
102 "configfs. It does not support the creation of child config_items.\n"
103 "It only has a few attributes. In fact, it isn't much different\n"
104 "than a directory in /proc.\n");
107 CONFIGFS_ATTR_RO(childless_, showme);
108 CONFIGFS_ATTR(childless_, storeme);
109 CONFIGFS_ATTR_RO(childless_, description);
111 static struct configfs_attribute *childless_attrs[] = {
112 &childless_attr_showme,
113 &childless_attr_storeme,
114 &childless_attr_description,
115 NULL,
118 static struct config_item_type childless_type = {
119 .ct_attrs = childless_attrs,
120 .ct_owner = THIS_MODULE,
123 static struct childless childless_subsys = {
124 .subsys = {
125 .su_group = {
126 .cg_item = {
127 .ci_namebuf = "01-childless",
128 .ci_type = &childless_type,
135 /* ----------------------------------------------------------------- */
138 * 02-simple-children
140 * This example merely has a simple one-attribute child. Note that
141 * there is no extra attribute structure, as the child's attribute is
142 * known from the get-go. Also, there is no container for the
143 * subsystem, as it has no attributes of its own.
146 struct simple_child {
147 struct config_item item;
148 int storeme;
151 static inline struct simple_child *to_simple_child(struct config_item *item)
153 return item ? container_of(item, struct simple_child, item) : NULL;
156 static ssize_t simple_child_storeme_show(struct config_item *item, char *page)
158 return sprintf(page, "%d\n", to_simple_child(item)->storeme);
161 static ssize_t simple_child_storeme_store(struct config_item *item,
162 const char *page, size_t count)
164 struct simple_child *simple_child = to_simple_child(item);
165 unsigned long tmp;
166 char *p = (char *) page;
168 tmp = simple_strtoul(p, &p, 10);
169 if (!p || (*p && (*p != '\n')))
170 return -EINVAL;
172 if (tmp > INT_MAX)
173 return -ERANGE;
175 simple_child->storeme = tmp;
177 return count;
180 CONFIGFS_ATTR(simple_child_, storeme);
182 static struct configfs_attribute *simple_child_attrs[] = {
183 &simple_child_attr_storeme,
184 NULL,
187 static void simple_child_release(struct config_item *item)
189 kfree(to_simple_child(item));
192 static struct configfs_item_operations simple_child_item_ops = {
193 .release = simple_child_release,
196 static struct config_item_type simple_child_type = {
197 .ct_item_ops = &simple_child_item_ops,
198 .ct_attrs = simple_child_attrs,
199 .ct_owner = THIS_MODULE,
203 struct simple_children {
204 struct config_group group;
207 static inline struct simple_children *to_simple_children(struct config_item *item)
209 return item ? container_of(to_config_group(item),
210 struct simple_children, group) : NULL;
213 static struct config_item *simple_children_make_item(struct config_group *group,
214 const char *name)
216 struct simple_child *simple_child;
218 simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
219 if (!simple_child)
220 return ERR_PTR(-ENOMEM);
222 config_item_init_type_name(&simple_child->item, name,
223 &simple_child_type);
225 simple_child->storeme = 0;
227 return &simple_child->item;
230 static ssize_t simple_children_description_show(struct config_item *item,
231 char *page)
233 return sprintf(page,
234 "[02-simple-children]\n"
235 "\n"
236 "This subsystem allows the creation of child config_items. These\n"
237 "items have only one attribute that is readable and writeable.\n");
240 CONFIGFS_ATTR_RO(simple_children_, description);
242 static struct configfs_attribute *simple_children_attrs[] = {
243 &simple_children_attr_description,
244 NULL,
247 static void simple_children_release(struct config_item *item)
249 kfree(to_simple_children(item));
252 static struct configfs_item_operations simple_children_item_ops = {
253 .release = simple_children_release,
257 * Note that, since no extra work is required on ->drop_item(),
258 * no ->drop_item() is provided.
260 static struct configfs_group_operations simple_children_group_ops = {
261 .make_item = simple_children_make_item,
264 static struct config_item_type simple_children_type = {
265 .ct_item_ops = &simple_children_item_ops,
266 .ct_group_ops = &simple_children_group_ops,
267 .ct_attrs = simple_children_attrs,
268 .ct_owner = THIS_MODULE,
271 static struct configfs_subsystem simple_children_subsys = {
272 .su_group = {
273 .cg_item = {
274 .ci_namebuf = "02-simple-children",
275 .ci_type = &simple_children_type,
281 /* ----------------------------------------------------------------- */
284 * 03-group-children
286 * This example reuses the simple_children group from above. However,
287 * the simple_children group is not the subsystem itself, it is a
288 * child of the subsystem. Creation of a group in the subsystem creates
289 * a new simple_children group. That group can then have simple_child
290 * children of its own.
293 static struct config_group *group_children_make_group(
294 struct config_group *group, const char *name)
296 struct simple_children *simple_children;
298 simple_children = kzalloc(sizeof(struct simple_children),
299 GFP_KERNEL);
300 if (!simple_children)
301 return ERR_PTR(-ENOMEM);
303 config_group_init_type_name(&simple_children->group, name,
304 &simple_children_type);
306 return &simple_children->group;
309 static ssize_t group_children_description_show(struct config_item *item,
310 char *page)
312 return sprintf(page,
313 "[03-group-children]\n"
314 "\n"
315 "This subsystem allows the creation of child config_groups. These\n"
316 "groups are like the subsystem simple-children.\n");
319 CONFIGFS_ATTR_RO(group_children_, description);
321 static struct configfs_attribute *group_children_attrs[] = {
322 &group_children_attr_description,
323 NULL,
327 * Note that, since no extra work is required on ->drop_item(),
328 * no ->drop_item() is provided.
330 static struct configfs_group_operations group_children_group_ops = {
331 .make_group = group_children_make_group,
334 static struct config_item_type group_children_type = {
335 .ct_group_ops = &group_children_group_ops,
336 .ct_attrs = group_children_attrs,
337 .ct_owner = THIS_MODULE,
340 static struct configfs_subsystem group_children_subsys = {
341 .su_group = {
342 .cg_item = {
343 .ci_namebuf = "03-group-children",
344 .ci_type = &group_children_type,
349 /* ----------------------------------------------------------------- */
352 * We're now done with our subsystem definitions.
353 * For convenience in this module, here's a list of them all. It
354 * allows the init function to easily register them. Most modules
355 * will only have one subsystem, and will only call register_subsystem
356 * on it directly.
358 static struct configfs_subsystem *example_subsys[] = {
359 &childless_subsys.subsys,
360 &simple_children_subsys,
361 &group_children_subsys,
362 NULL,
365 static int __init configfs_example_init(void)
367 int ret;
368 int i;
369 struct configfs_subsystem *subsys;
371 for (i = 0; example_subsys[i]; i++) {
372 subsys = example_subsys[i];
374 config_group_init(&subsys->su_group);
375 mutex_init(&subsys->su_mutex);
376 ret = configfs_register_subsystem(subsys);
377 if (ret) {
378 printk(KERN_ERR "Error %d while registering subsystem %s\n",
379 ret,
380 subsys->su_group.cg_item.ci_namebuf);
381 goto out_unregister;
385 return 0;
387 out_unregister:
388 for (i--; i >= 0; i--)
389 configfs_unregister_subsystem(example_subsys[i]);
391 return ret;
394 static void __exit configfs_example_exit(void)
396 int i;
398 for (i = 0; example_subsys[i]; i++)
399 configfs_unregister_subsystem(example_subsys[i]);
402 module_init(configfs_example_init);
403 module_exit(configfs_example_exit);
404 MODULE_LICENSE("GPL");