mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Masahiro Yamada](/assets/img/avatar_default.png)
The section "19) Editor modelines and other cruft" in Documentation/process/coding-style.rst clearly says, "Do not include any of these in source files." I recently receive a patch to explicitly add a new one. Let's do treewide cleanups, otherwise some people follow the existing code and attempt to upstream their favoriate editor setups. It is even nicer if scripts/checkpatch.pl can check it. If we like to impose coding style in an editor-independent manner, I think editorconfig (patch [1]) is a saner solution. [1] https://lore.kernel.org/lkml/20200703073143.423557-1-danny@kdrag0n.dev/ Link: https://lkml.kernel.org/r/20210324054457.1477489-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> [auxdisplay] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
367 lines
8.9 KiB
C
367 lines
8.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* configfs_example_macros.c - This file is a demonstration module
|
|
* containing a number of configfs subsystems. It uses the helper
|
|
* macros defined by configfs.h
|
|
*
|
|
* 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/kernel.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;
|
|
};
|
|
|
|
static inline struct childless *to_childless(struct config_item *item)
|
|
{
|
|
return container_of(to_configfs_subsystem(to_config_group(item)),
|
|
struct childless, subsys);
|
|
}
|
|
|
|
static ssize_t childless_showme_show(struct config_item *item, char *page)
|
|
{
|
|
struct childless *childless = to_childless(item);
|
|
ssize_t pos;
|
|
|
|
pos = sprintf(page, "%d\n", childless->showme);
|
|
childless->showme++;
|
|
|
|
return pos;
|
|
}
|
|
|
|
static ssize_t childless_storeme_show(struct config_item *item, char *page)
|
|
{
|
|
return sprintf(page, "%d\n", to_childless(item)->storeme);
|
|
}
|
|
|
|
static ssize_t childless_storeme_store(struct config_item *item,
|
|
const char *page, size_t count)
|
|
{
|
|
struct childless *childless = to_childless(item);
|
|
int ret;
|
|
|
|
ret = kstrtoint(page, 10, &childless->storeme);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return count;
|
|
}
|
|
|
|
static ssize_t childless_description_show(struct config_item *item, 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");
|
|
}
|
|
|
|
CONFIGFS_ATTR_RO(childless_, showme);
|
|
CONFIGFS_ATTR(childless_, storeme);
|
|
CONFIGFS_ATTR_RO(childless_, description);
|
|
|
|
static struct configfs_attribute *childless_attrs[] = {
|
|
&childless_attr_showme,
|
|
&childless_attr_storeme,
|
|
&childless_attr_description,
|
|
NULL,
|
|
};
|
|
|
|
static const struct config_item_type childless_type = {
|
|
.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 container_of(item, struct simple_child, item);
|
|
}
|
|
|
|
static ssize_t simple_child_storeme_show(struct config_item *item, char *page)
|
|
{
|
|
return sprintf(page, "%d\n", to_simple_child(item)->storeme);
|
|
}
|
|
|
|
static ssize_t simple_child_storeme_store(struct config_item *item,
|
|
const char *page, size_t count)
|
|
{
|
|
struct simple_child *simple_child = to_simple_child(item);
|
|
int ret;
|
|
|
|
ret = kstrtoint(page, 10, &simple_child->storeme);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return count;
|
|
}
|
|
|
|
CONFIGFS_ATTR(simple_child_, storeme);
|
|
|
|
static struct configfs_attribute *simple_child_attrs[] = {
|
|
&simple_child_attr_storeme,
|
|
NULL,
|
|
};
|
|
|
|
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,
|
|
};
|
|
|
|
static const 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 container_of(to_config_group(item),
|
|
struct simple_children, group);
|
|
}
|
|
|
|
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);
|
|
|
|
return &simple_child->item;
|
|
}
|
|
|
|
static ssize_t simple_children_description_show(struct config_item *item,
|
|
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");
|
|
}
|
|
|
|
CONFIGFS_ATTR_RO(simple_children_, description);
|
|
|
|
static struct configfs_attribute *simple_children_attrs[] = {
|
|
&simple_children_attr_description,
|
|
NULL,
|
|
};
|
|
|
|
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,
|
|
};
|
|
|
|
/*
|
|
* 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 const 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 ssize_t group_children_description_show(struct config_item *item,
|
|
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");
|
|
}
|
|
|
|
CONFIGFS_ATTR_RO(group_children_, description);
|
|
|
|
static struct configfs_attribute *group_children_attrs[] = {
|
|
&group_children_attr_description,
|
|
NULL,
|
|
};
|
|
|
|
/*
|
|
* 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 const struct config_item_type group_children_type = {
|
|
.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)
|
|
{
|
|
struct configfs_subsystem *subsys;
|
|
int ret, i;
|
|
|
|
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) {
|
|
pr_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");
|