[mirror_ubuntu-bionic-kernel.git] / fs / sysfs / sysfs.h

/*
 * 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.
 */

#include <linux/lockdep.h>
#include <linux/kobject_ns.h>
#include <linux/fs.h>

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;

	unsigned long		subdirs;
};

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;
	struct hlist_head	buffers;
};

struct sysfs_inode_attrs {
	struct iattr	ia_iattr;
	void		*ia_secdata;
	u32		ia_secdata_len;
};

/*
 * 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;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	struct lockdep_map	dep_map;
#endif
	struct sysfs_dirent	*s_parent;
	struct sysfs_dirent	*s_sibling;
	const char		*s_name;

	const void		*s_ns; /* namespace tag */
	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;
	unsigned short		s_mode;
	ino_t			s_ino;
	struct sysfs_inode_attrs *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_ACTIVE_REF		(SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR)

/* identify any namespace tag on sysfs_dirents */
#define SYSFS_NS_TYPE_MASK		0xff00
#define SYSFS_NS_TYPE_SHIFT		8

#define SYSFS_FLAG_MASK			~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK)
#define SYSFS_FLAG_REMOVED		0x020000

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

/*
 * Return any namespace tags on this dirent.
 * enum kobj_ns_type is defined in linux/kobject.h
 */
static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd)
{
	return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT;
}

#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define sysfs_dirent_init_lockdep(sd)				\
do {								\
	struct attribute *attr = sd->s_attr.attr;		\
	struct lock_class_key *key = attr->key;			\
	if (!key)						\
		key = &attr->skey;				\
								\
	lockdep_init_map(&sd->dep_map, "s_active", key, 0);	\
} while(0)
#else
#define sysfs_dirent_init_lockdep(sd) do {} while(0)
#endif

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

/*
 * mount.c
 */

/*
 * Each sb is associated with a set of namespace tags (i.e.
 * the network namespace of the task which mounted this sysfs
 * instance).
 */
struct sysfs_super_info {
	void *ns[KOBJ_NS_TYPES];
};
#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
extern struct sysfs_dirent sysfs_root;
extern struct kmem_cache *sysfs_dir_cachep;

/*
 * dir.c
 */
extern struct mutex sysfs_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(struct sysfs_dirent *sd);
void sysfs_put_active(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 void *ns,
				       const unsigned char *name);
struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
				      const void *ns,
				      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);

int sysfs_rename(struct sysfs_dirent *sd,
	struct sysfs_dirent *new_parent_sd, const void *ns, const char *new_name);

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;
}
#define sysfs_get(sd) __sysfs_get(sd)

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

/*
 * inode.c
 */
struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
void sysfs_evict_inode(struct inode *inode);
int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr);
int sysfs_permission(struct inode *inode, int mask);
int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
		size_t size, int flags);
int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, 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;
void unmap_bin_file(struct sysfs_dirent *attr_sd);

/*
 * symlink.c
 */
extern const struct inode_operations sysfs_symlink_inode_operations;
Commit	Line	Data
6d66f5cd TH	1	/*
	2	* fs/sysfs/sysfs.h - sysfs internal header file
	3	*
	4	* Copyright (c) 2001-3 Patrick Mochel
	5	* Copyright (c) 2007 SUSE Linux Products GmbH
	6	* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
	7	*
	8	* This file is released under the GPLv2.
	9	*/
	10
846f9974	11	#include <linux/lockdep.h>
57cc7215	12	#include <linux/kobject_ns.h>
ddd29ec6 DQ	13	#include <linux/fs.h>
ddd29ec6 DQ	14
85a4ffad TH	15	struct sysfs_open_dirent;
85a4ffad TH	16
59f69015	17	/* type-specific structures for sysfs_dirent->s_* union members */
3e519038	18	struct sysfs_elem_dir {
59f69015	19	struct kobject *kobj;
bc747f37 TH	20	/* children list starts here and goes through sd->s_sibling */
bc747f37 TH	21	struct sysfs_dirent *children;
7f9838fd MP	22
7f9838fd MP	23	unsigned long subdirs;
3e519038 TH	24	};
	25
	26	struct sysfs_elem_symlink {
59f69015	27	struct sysfs_dirent *target_sd;
3e519038 TH	28	};
	29
	30	struct sysfs_elem_attr {
59f69015	31	struct attribute *attr;
85a4ffad	32	struct sysfs_open_dirent *open;
3e519038 TH	33	};
	34
	35	struct sysfs_elem_bin_attr {
59f69015	36	struct bin_attribute *bin_attr;
e0edd3c6	37	struct hlist_head buffers;
3e519038 TH	38	};
3e519038 TH	39
ddd29ec6 DQ	40	struct sysfs_inode_attrs {
	41	struct iattr ia_iattr;
	42	void *ia_secdata;
	43	u32 ia_secdata_len;
	44	};
	45
0ab66088	46	/*
59f69015 TH	47	* sysfs_dirent - the building block of sysfs hierarchy. Each and
	48	* every sysfs node is represented by single sysfs_dirent.
	49	*
0ab66088 TH	50	* As long as s_count reference is held, the sysfs_dirent itself is
	51	* accessible. Dereferencing s_elem or any other outer entity
	52	* requires s_active reference.
	53	*/
d56c3eae AR	54	struct sysfs_dirent {
d56c3eae AR	55	atomic_t s_count;
8619f979	56	atomic_t s_active;
846f9974 EB	57	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	58	struct lockdep_map dep_map;
	59	#endif
59f69015 TH	60	struct sysfs_dirent *s_parent;
59f69015 TH	61	struct sysfs_dirent *s_sibling;
59f69015	62	const char *s_name;
3e519038	63
be867b19	64	const void s_ns; / namespace tag */
3e519038	65	union {
b1fc3d61 TH	66	struct sysfs_elem_dir s_dir;
	67	struct sysfs_elem_symlink s_symlink;
	68	struct sysfs_elem_attr s_attr;
	69	struct sysfs_elem_bin_attr s_bin_attr;
	70	};
3e519038	71
b402d72c	72	unsigned int s_flags;
19c38b63	73	unsigned short s_mode;
dc351252	74	ino_t s_ino;
ddd29ec6	75	struct sysfs_inode_attrs *s_iattr;
d56c3eae	76	};
1da177e4	77
59f69015	78	#define SD_DEACTIVATED_BIAS INT_MIN
0ab66088	79
59f69015	80	#define SYSFS_TYPE_MASK 0x00ff
dc2f75f0 TH	81	#define SYSFS_DIR 0x0001
	82	#define SYSFS_KOBJ_ATTR 0x0002
	83	#define SYSFS_KOBJ_BIN_ATTR 0x0004
	84	#define SYSFS_KOBJ_LINK 0x0008
59f69015	85	#define SYSFS_COPY_NAME (SYSFS_DIR \| SYSFS_KOBJ_LINK)
a2db6842	86	#define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR \| SYSFS_KOBJ_BIN_ATTR)
59f69015	87
be867b19	88	/* identify any namespace tag on sysfs_dirents */
3ff195b0 EB	89	#define SYSFS_NS_TYPE_MASK 0xff00
	90	#define SYSFS_NS_TYPE_SHIFT 8
	91
	92	#define SYSFS_FLAG_MASK ~(SYSFS_NS_TYPE_MASK\|SYSFS_TYPE_MASK)
	93	#define SYSFS_FLAG_REMOVED 0x020000
59f69015 TH	94
	95	static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
	96	{
	97	return sd->s_flags & SYSFS_TYPE_MASK;
	98	}
	99
be867b19 SH	100	/*
	101	* Return any namespace tags on this dirent.
	102	* enum kobj_ns_type is defined in linux/kobject.h
	103	*/
3ff195b0 EB	104	static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd)
	105	{
	106	return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT;
	107	}
	108
846f9974 EB	109	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	110	#define sysfs_dirent_init_lockdep(sd) \
	111	do { \
6992f533 EB	112	struct attribute *attr = sd->s_attr.attr; \
	113	struct lock_class_key *key = attr->key; \
	114	if (!key) \
	115	key = &attr->skey; \
846f9974	116	\
6992f533	117	lockdep_init_map(&sd->dep_map, "s_active", key, 0); \
846f9974 EB	118	} while(0)
	119	#else
	120	#define sysfs_dirent_init_lockdep(sd) do {} while(0)
	121	#endif
	122
59f69015 TH	123	/*
	124	* Context structure to be used while adding/removing nodes.
	125	*/
fb6896da TH	126	struct sysfs_addrm_cxt {
fb6896da TH	127	struct sysfs_dirent *parent_sd;
fb6896da	128	struct sysfs_dirent *removed;
fb6896da TH	129	};
fb6896da TH	130
59f69015 TH	131	/*
	132	* mount.c
	133	*/
be867b19 SH	134
	135	/*
	136	* Each sb is associated with a set of namespace tags (i.e.
	137	* the network namespace of the task which mounted this sysfs
	138	* instance).
	139	*/
9e7fdd25	140	struct sysfs_super_info {
a685e089	141	void *ns[KOBJ_NS_TYPES];
9e7fdd25 EB	142	};
9e7fdd25 EB	143	#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
51225039	144	extern struct sysfs_dirent sysfs_root;
e18b890b	145	extern struct kmem_cache *sysfs_dir_cachep;
1da177e4	146
59f69015 TH	147	/*
	148	* dir.c
	149	*/
3007e997	150	extern struct mutex sysfs_mutex;
59f69015 TH	151	extern spinlock_t sysfs_assoc_lock;
59f69015 TH	152
4b6f5d20	153	extern const struct file_operations sysfs_dir_operations;
c5ef1c42	154	extern const struct inode_operations sysfs_dir_inode_operations;
1da177e4	155
59f69015	156	struct dentry sysfs_get_dentry(struct sysfs_dirent sd);
e72ceb8c EB	157	struct sysfs_dirent sysfs_get_active(struct sysfs_dirent sd);
e72ceb8c EB	158	void sysfs_put_active(struct sysfs_dirent *sd);
59f69015 TH	159	void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
59f69015 TH	160	struct sysfs_dirent *parent_sd);
36ce6dad	161	int __sysfs_add_one(struct sysfs_addrm_cxt acxt, struct sysfs_dirent sd);
59f69015 TH	162	int sysfs_add_one(struct sysfs_addrm_cxt acxt, struct sysfs_dirent sd);
	163	void sysfs_remove_one(struct sysfs_addrm_cxt acxt, struct sysfs_dirent sd);
	164	void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
	165
	166	struct sysfs_dirent sysfs_find_dirent(struct sysfs_dirent parent_sd,
3ff195b0	167	const void *ns,
59f69015 TH	168	const unsigned char *name);
59f69015 TH	169	struct sysfs_dirent sysfs_get_dirent(struct sysfs_dirent parent_sd,
3ff195b0	170	const void *ns,
59f69015 TH	171	const unsigned char *name);
	172	struct sysfs_dirent sysfs_new_dirent(const char name, umode_t mode, int type);
	173
	174	void release_sysfs_dirent(struct sysfs_dirent *sd);
	175
	176	int sysfs_create_subdir(struct kobject kobj, const char name,
	177	struct sysfs_dirent **p_sd);
	178	void sysfs_remove_subdir(struct sysfs_dirent *sd);
	179
ca1bab38	180	int sysfs_rename(struct sysfs_dirent *sd,
3ff195b0	181	struct sysfs_dirent new_parent_sd, const void ns, const char *new_name);
ca1bab38	182
f1282c84	183	static inline struct sysfs_dirent __sysfs_get(struct sysfs_dirent sd)
1da177e4	184	{
0ab66088 TH	185	if (sd) {
	186	WARN_ON(!atomic_read(&sd->s_count));
	187	atomic_inc(&sd->s_count);
	188	}
	189	return sd;
1da177e4	190	}
f1282c84	191	#define sysfs_get(sd) __sysfs_get(sd)
1da177e4	192
f1282c84	193	static inline void __sysfs_put(struct sysfs_dirent *sd)
1da177e4	194	{
0ab66088 TH	195	if (sd && atomic_dec_and_test(&sd->s_count))
	196	release_sysfs_dirent(sd);
	197	}
f1282c84	198	#define sysfs_put(sd) __sysfs_put(sd)
59f69015 TH	199
	200	/*
	201	* inode.c
	202	*/
fac2622b	203	struct inode sysfs_get_inode(struct super_block sb, struct sysfs_dirent *sd);
01cd9fef	204	void sysfs_evict_inode(struct inode *inode);
35df63c4	205	int sysfs_sd_setattr(struct sysfs_dirent sd, struct iattr iattr);
10556cb2	206	int sysfs_permission(struct inode *inode, int mask);
59f69015	207	int sysfs_setattr(struct dentry dentry, struct iattr iattr);
e61ab4ae	208	int sysfs_getattr(struct vfsmount mnt, struct dentry dentry, struct kstat *stat);
ddd29ec6 DQ	209	int sysfs_setxattr(struct dentry dentry, const char name, const void *value,
ddd29ec6 DQ	210	size_t size, int flags);
3ff195b0	211	int sysfs_hash_and_remove(struct sysfs_dirent dir_sd, const void ns, const char *name);
e0bf68dd	212	int sysfs_inode_init(void);
59f69015 TH	213
	214	/*
	215	* file.c
	216	*/
	217	extern const struct file_operations sysfs_file_operations;
	218
	219	int sysfs_add_file(struct sysfs_dirent *dir_sd,
	220	const struct attribute *attr, int type);
	221
0f423895 JB	222	int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
0f423895 JB	223	const struct attribute *attr, int type, mode_t amode);
59f69015 TH	224	/*
	225	* bin.c
	226	*/
	227	extern const struct file_operations bin_fops;
e0edd3c6	228	void unmap_bin_file(struct sysfs_dirent *attr_sd);
59f69015 TH	229
	230	/*
	231	* symlink.c
	232	*/
	233	extern const struct inode_operations sysfs_symlink_inode_operations;