root/fs/sysfs/sysfs.h

INCLUDED FROM

DEFINITIONS

1. sysfs_type
2. sysfs_get
3. sysfs_put

/*
 * fs/sysfs/sysfs.h - sysfs internal header file
 *
 * Copyright (c) 2001-3 Patrick Mochel
 * Copyright (c) 2007 SUSE Linux Products GmbH
 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
 *
 * This file is released under the GPLv2.
 */

struct sysfs_open_dirent;

/* type-specific structures for sysfs_dirent->s_* union members */
struct sysfs_elem_dir {
        struct kobject          *kobj;
        /* children list starts here and goes through sd->s_sibling */
        struct sysfs_dirent     *children;
};

struct sysfs_elem_symlink {
        struct sysfs_dirent     *target_sd;
};

struct sysfs_elem_attr {
        struct attribute        *attr;
        struct sysfs_open_dirent *open;
};

struct sysfs_elem_bin_attr {
        struct bin_attribute    *bin_attr;
};

/*
 * sysfs_dirent - the building block of sysfs hierarchy.  Each and
 * every sysfs node is represented by single sysfs_dirent.
 *
 * As long as s_count reference is held, the sysfs_dirent itself is
 * accessible.  Dereferencing s_elem or any other outer entity
 * requires s_active reference.
 */
struct sysfs_dirent {
        atomic_t                s_count;
        atomic_t                s_active;
        struct sysfs_dirent     *s_parent;
        struct sysfs_dirent     *s_sibling;
        const char              *s_name;

        union {
                struct sysfs_elem_dir           s_dir;
                struct sysfs_elem_symlink       s_symlink;
                struct sysfs_elem_attr          s_attr;
                struct sysfs_elem_bin_attr      s_bin_attr;
        };

        unsigned int            s_flags;
        ino_t                   s_ino;
        umode_t                 s_mode;
        struct iattr            *s_iattr;
};

#define SD_DEACTIVATED_BIAS             INT_MIN

#define SYSFS_TYPE_MASK                 0x00ff
#define SYSFS_DIR                       0x0001
#define SYSFS_KOBJ_ATTR                 0x0002
#define SYSFS_KOBJ_BIN_ATTR             0x0004
#define SYSFS_KOBJ_LINK                 0x0008
#define SYSFS_COPY_NAME                 (SYSFS_DIR | SYSFS_KOBJ_LINK)

#define SYSFS_FLAG_MASK                 ~SYSFS_TYPE_MASK
#define SYSFS_FLAG_REMOVED              0x0200

static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
{
        return sd->s_flags & SYSFS_TYPE_MASK;
}

/*
 * Context structure to be used while adding/removing nodes.
 */
struct sysfs_addrm_cxt {
        struct sysfs_dirent     *parent_sd;
        struct inode            *parent_inode;
        struct sysfs_dirent     *removed;
        int                     cnt;
};

/*
 * mount.c
 */
extern struct sysfs_dirent sysfs_root;
extern struct super_block *sysfs_sb;
extern struct kmem_cache *sysfs_dir_cachep;

/*
 * dir.c
 */
extern struct mutex sysfs_mutex;
extern struct mutex sysfs_rename_mutex;
extern spinlock_t sysfs_assoc_lock;

extern const struct file_operations sysfs_dir_operations;
extern const struct inode_operations sysfs_dir_inode_operations;

struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
void sysfs_put_active_two(struct sysfs_dirent *sd);
void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
                       struct sysfs_dirent *parent_sd);
int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);

struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
                                       const unsigned char *name);
struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
                                      const unsigned char *name);
struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);

void release_sysfs_dirent(struct sysfs_dirent *sd);

int sysfs_create_subdir(struct kobject *kobj, const char *name,
                        struct sysfs_dirent **p_sd);
void sysfs_remove_subdir(struct sysfs_dirent *sd);

static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
{
        if (sd) {
                WARN_ON(!atomic_read(&sd->s_count));
                atomic_inc(&sd->s_count);
        }
        return sd;
}

static inline void sysfs_put(struct sysfs_dirent *sd)
{
        if (sd && atomic_dec_and_test(&sd->s_count))
                release_sysfs_dirent(sd);
}

/*
 * inode.c
 */
struct inode *sysfs_get_inode(struct sysfs_dirent *sd);
int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
int sysfs_inode_init(void);

/*
 * file.c
 */
extern const struct file_operations sysfs_file_operations;

int sysfs_add_file(struct sysfs_dirent *dir_sd,
                   const struct attribute *attr, int type);

int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
                        const struct attribute *attr, int type, mode_t amode);
/*
 * bin.c
 */
extern const struct file_operations bin_fops;

/*
 * symlink.c
 */
extern const struct inode_operations sysfs_symlink_inode_operations;