linux/fs/configfs/configfs_internal.h
Al Viro e9c03af21c configfs: calculate the symlink target only once
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-11 12:46:14 +02:00

160 lines
4.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* -*- mode: c; c-basic-offset:8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* configfs_internal.h - Internal stuff for configfs
*
* Based on sysfs:
* sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
*
* configfs Copyright (C) 2005 Oracle. All rights reserved.
*/
#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/spinlock.h>
struct configfs_fragment {
atomic_t frag_count;
struct rw_semaphore frag_sem;
bool frag_dead;
};
void put_fragment(struct configfs_fragment *);
struct configfs_fragment *get_fragment(struct configfs_fragment *);
struct configfs_dirent {
atomic_t s_count;
int s_dependent_count;
struct list_head s_sibling;
struct list_head s_children;
int s_links;
void * s_element;
int s_type;
umode_t s_mode;
struct dentry * s_dentry;
struct iattr * s_iattr;
#ifdef CONFIG_LOCKDEP
int s_depth;
#endif
struct configfs_fragment *s_frag;
};
#define CONFIGFS_ROOT 0x0001
#define CONFIGFS_DIR 0x0002
#define CONFIGFS_ITEM_ATTR 0x0004
#define CONFIGFS_ITEM_BIN_ATTR 0x0008
#define CONFIGFS_ITEM_LINK 0x0020
#define CONFIGFS_USET_DIR 0x0040
#define CONFIGFS_USET_DEFAULT 0x0080
#define CONFIGFS_USET_DROPPING 0x0100
#define CONFIGFS_USET_IN_MKDIR 0x0200
#define CONFIGFS_USET_CREATING 0x0400
#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)
extern struct mutex configfs_symlink_mutex;
extern spinlock_t configfs_dirent_lock;
extern struct kmem_cache *configfs_dir_cachep;
extern int configfs_is_root(struct config_item *item);
extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, struct super_block *);
extern struct inode *configfs_create(struct dentry *, umode_t mode);
extern int configfs_create_file(struct config_item *, const struct configfs_attribute *);
extern int configfs_create_bin_file(struct config_item *,
const struct configfs_bin_attribute *);
extern int configfs_make_dirent(struct configfs_dirent *, struct dentry *,
void *, umode_t, int, struct configfs_fragment *);
extern int configfs_dirent_is_ready(struct configfs_dirent *);
extern void configfs_hash_and_remove(struct dentry * dir, const char * name);
extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);
extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent);
extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr);
extern struct dentry *configfs_pin_fs(void);
extern void configfs_release_fs(void);
extern const struct file_operations configfs_dir_operations;
extern const struct file_operations configfs_file_operations;
extern const struct file_operations configfs_bin_file_operations;
extern const struct inode_operations configfs_dir_inode_operations;
extern const struct inode_operations configfs_root_inode_operations;
extern const struct inode_operations configfs_symlink_inode_operations;
extern const struct dentry_operations configfs_dentry_ops;
extern int configfs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname);
extern int configfs_unlink(struct inode *dir, struct dentry *dentry);
int configfs_create_link(struct configfs_dirent *target, struct dentry *parent,
struct dentry *dentry, char *body);
static inline struct config_item * to_item(struct dentry * dentry)
{
struct configfs_dirent * sd = dentry->d_fsdata;
return ((struct config_item *) sd->s_element);
}
static inline struct configfs_attribute * to_attr(struct dentry * dentry)
{
struct configfs_dirent * sd = dentry->d_fsdata;
return ((struct configfs_attribute *) sd->s_element);
}
static inline struct configfs_bin_attribute *to_bin_attr(struct dentry *dentry)
{
struct configfs_attribute *attr = to_attr(dentry);
return container_of(attr, struct configfs_bin_attribute, cb_attr);
}
static inline struct config_item *configfs_get_config_item(struct dentry *dentry)
{
struct config_item * item = NULL;
spin_lock(&dentry->d_lock);
if (!d_unhashed(dentry)) {
struct configfs_dirent * sd = dentry->d_fsdata;
item = config_item_get(sd->s_element);
}
spin_unlock(&dentry->d_lock);
return item;
}
static inline void release_configfs_dirent(struct configfs_dirent * sd)
{
if (!(sd->s_type & CONFIGFS_ROOT)) {
kfree(sd->s_iattr);
put_fragment(sd->s_frag);
kmem_cache_free(configfs_dir_cachep, sd);
}
}
static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd)
{
if (sd) {
WARN_ON(!atomic_read(&sd->s_count));
atomic_inc(&sd->s_count);
}
return sd;
}
static inline void configfs_put(struct configfs_dirent * sd)
{
WARN_ON(!atomic_read(&sd->s_count));
if (atomic_dec_and_test(&sd->s_count))
release_configfs_dirent(sd);
}