linux_dsm_epyc7002/include/linux/sysfs.h
Eric W. Biederman 6992f53349 sysfs: Use one lockdep class per sysfs attribute.
Acknowledge that the logical sysfs rwsem has one instance per
sysfs attribute with different locking depencencies for different
attributes.

There is a sysfs idiom where writing to one sysfs file causes the
addition or removal of other sysfs files.   Lumping all of the
sysfs attributes together in one lock class causes lockdep to
generate lots of false positives.

This introduces the requirement that non-static sysfs attributes
need to be initialized with sysfs_attr_init or sysfs_bin_attr_init.
Strictly speaking this requirement only exists when lockdep is
enabled, and when lockdep is enabled we get a bit fat warning
if this requirement is not met.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-07 17:04:51 -08:00

299 lines
7.3 KiB
C

/*
* sysfs.h - definitions for the device driver filesystem
*
* Copyright (c) 2001,2002 Patrick Mochel
* Copyright (c) 2004 Silicon Graphics, Inc.
* Copyright (c) 2007 SUSE Linux Products GmbH
* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
*
* Please see Documentation/filesystems/sysfs.txt for more information.
*/
#ifndef _SYSFS_H_
#define _SYSFS_H_
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <asm/atomic.h>
struct kobject;
struct module;
/* FIXME
* The *owner field is no longer used.
* x86 tree has been cleaned up. The owner
* attribute is still left for other arches.
*/
struct attribute {
const char *name;
struct module *owner;
mode_t mode;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lock_class_key *key;
struct lock_class_key skey;
#endif
};
#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define sysfs_attr_init(attr) \
do { \
static struct lock_class_key __key; \
\
(attr)->key = &__key; \
} while(0)
#else
#define sysfs_attr_init(attr) do {} while(0)
#endif
struct attribute_group {
const char *name;
mode_t (*is_visible)(struct kobject *,
struct attribute *, int);
struct attribute **attrs;
};
/**
* Use these macros to make defining attributes easier. See include/linux/device.h
* for examples..
*/
#define __ATTR(_name,_mode,_show,_store) { \
.attr = {.name = __stringify(_name), .mode = _mode }, \
.show = _show, \
.store = _store, \
}
#define __ATTR_RO(_name) { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = _name##_show, \
}
#define __ATTR_NULL { .attr = { .name = NULL } }
#define attr_name(_attr) (_attr).attr.name
struct vm_area_struct;
struct bin_attribute {
struct attribute attr;
size_t size;
void *private;
ssize_t (*read)(struct kobject *, struct bin_attribute *,
char *, loff_t, size_t);
ssize_t (*write)(struct kobject *, struct bin_attribute *,
char *, loff_t, size_t);
int (*mmap)(struct kobject *, struct bin_attribute *attr,
struct vm_area_struct *vma);
};
#define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&bin_attr->attr)
struct sysfs_ops {
ssize_t (*show)(struct kobject *, struct attribute *,char *);
ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t);
};
struct sysfs_dirent;
#ifdef CONFIG_SYSFS
int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
void *data, struct module *owner);
int __must_check sysfs_create_dir(struct kobject *kobj);
void sysfs_remove_dir(struct kobject *kobj);
int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
int __must_check sysfs_move_dir(struct kobject *kobj,
struct kobject *new_parent_kobj);
int __must_check sysfs_create_file(struct kobject *kobj,
const struct attribute *attr);
int __must_check sysfs_create_files(struct kobject *kobj,
const struct attribute **attr);
int __must_check sysfs_chmod_file(struct kobject *kobj, struct attribute *attr,
mode_t mode);
void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
int __must_check sysfs_create_bin_file(struct kobject *kobj,
const struct bin_attribute *attr);
void sysfs_remove_bin_file(struct kobject *kobj,
const struct bin_attribute *attr);
int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
const char *name);
int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
struct kobject *target,
const char *name);
void sysfs_remove_link(struct kobject *kobj, const char *name);
int __must_check sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp);
int sysfs_update_group(struct kobject *kobj,
const struct attribute_group *grp);
void sysfs_remove_group(struct kobject *kobj,
const struct attribute_group *grp);
int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group);
void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group);
void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
void sysfs_notify_dirent(struct sysfs_dirent *sd);
struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
const unsigned char *name);
struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
void sysfs_put(struct sysfs_dirent *sd);
void sysfs_printk_last_file(void);
int __must_check sysfs_init(void);
#else /* CONFIG_SYSFS */
static inline int sysfs_schedule_callback(struct kobject *kobj,
void (*func)(void *), void *data, struct module *owner)
{
return -ENOSYS;
}
static inline int sysfs_create_dir(struct kobject *kobj)
{
return 0;
}
static inline void sysfs_remove_dir(struct kobject *kobj)
{
}
static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
{
return 0;
}
static inline int sysfs_move_dir(struct kobject *kobj,
struct kobject *new_parent_kobj)
{
return 0;
}
static inline int sysfs_create_file(struct kobject *kobj,
const struct attribute *attr)
{
return 0;
}
static inline int sysfs_create_files(struct kobject *kobj,
const struct attribute **attr)
{
return 0;
}
static inline int sysfs_chmod_file(struct kobject *kobj,
struct attribute *attr, mode_t mode)
{
return 0;
}
static inline void sysfs_remove_file(struct kobject *kobj,
const struct attribute *attr)
{
}
static inline void sysfs_remove_files(struct kobject *kobj,
const struct attribute **attr)
{
}
static inline int sysfs_create_bin_file(struct kobject *kobj,
const struct bin_attribute *attr)
{
return 0;
}
static inline void sysfs_remove_bin_file(struct kobject *kobj,
const struct bin_attribute *attr)
{
}
static inline int sysfs_create_link(struct kobject *kobj,
struct kobject *target, const char *name)
{
return 0;
}
static inline int sysfs_create_link_nowarn(struct kobject *kobj,
struct kobject *target,
const char *name)
{
return 0;
}
static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
{
}
static inline int sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp)
{
return 0;
}
static inline int sysfs_update_group(struct kobject *kobj,
const struct attribute_group *grp)
{
return 0;
}
static inline void sysfs_remove_group(struct kobject *kobj,
const struct attribute_group *grp)
{
}
static inline int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
return 0;
}
static inline void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
}
static inline void sysfs_notify(struct kobject *kobj, const char *dir,
const char *attr)
{
}
static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
{
}
static inline
struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
const unsigned char *name)
{
return NULL;
}
static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
{
return NULL;
}
static inline void sysfs_put(struct sysfs_dirent *sd)
{
}
static inline int __must_check sysfs_init(void)
{
return 0;
}
static inline void sysfs_printk_last_file(void)
{
}
#endif /* CONFIG_SYSFS */
#endif /* _SYSFS_H_ */