[deliverable/linux.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>
#include <linux/rbtree.h>

struct sysfs_open_dirent;

/* type-specific structures for sysfs_dirent->s_* union members */
struct sysfs_elem_dir {
	struct kobject		*kobj;

	unsigned long		subdirs;
	/* children rbtree starts here and goes through sd->s_rb */
	struct rb_root		children;
};

struct sysfs_elem_symlink {
	struct sysfs_dirent	*target_sd;
};

struct sysfs_elem_attr {
	union {
		struct attribute	*attr;
		struct bin_attribute	*bin_attr;
	};
	struct sysfs_open_dirent *open;
};

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;
	const char		*s_name;

	struct rb_node		s_rb;

	union {
		struct completion	*completion;
		struct sysfs_dirent	*removed_list;
	} u;

	const void		*s_ns; /* namespace tag */
	unsigned int		s_hash; /* ns + name hash */
	union {
		struct sysfs_elem_dir		s_dir;
		struct sysfs_elem_symlink	s_symlink;
		struct sysfs_elem_attr		s_attr;
	};

	unsigned short		s_flags;
	umode_t			s_mode;
	unsigned int		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)

#define SYSFS_FLAG_MASK			~SYSFS_TYPE_MASK
#define SYSFS_FLAG_HAS_NS		0x01000
#define SYSFS_FLAG_REMOVED		0x02000

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

#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)

/* Test for attributes that want to ignore lockdep for read-locking */
static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
{
	int type = sysfs_type(sd);

	return (type == SYSFS_KOBJ_ATTR || type == SYSFS_KOBJ_BIN_ATTR) &&
		sd->s_attr.attr->ignore_lockdep;
}

#else

#define sysfs_dirent_init_lockdep(sd) do {} while (0)

static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
{
	return true;
}

#endif

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

/*
 * mount.c
 */

/*
 * Each sb is associated with one namespace tag, currently the network
 * namespace of the task which mounted this sysfs instance.  If multiple
 * tags become necessary, make the following an array and compare
 * sysfs_dirent tag against every entry.
 */
struct sysfs_super_info {
	void *ns;
};
#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 dentry_operations sysfs_dentry_ops;

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

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);
void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name);
int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
		    struct sysfs_dirent *parent_sd);
int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
		  struct sysfs_dirent *parent_sd);
void sysfs_remove(struct sysfs_dirent *sd);
int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name,
			  const void *ns);
void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);

struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
				       const unsigned char *name,
				       const void *ns);
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);

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

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_inode_init(void);

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

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

int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
			   const struct attribute *attr, int type,
			   umode_t amode, const void *ns);
void sysfs_unmap_bin_file(struct sysfs_dirent *sd);

/*
 * symlink.c
 */
extern const struct inode_operations sysfs_symlink_inode_operations;
int sysfs_create_link_sd(struct sysfs_dirent *sd, struct kobject *target,
			 const char *name);
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	13	#include <linux/fs.h>
4f72c0ca	14	#include <linux/rbtree.h>
ddd29ec6	15
85a4ffad TH	16	struct sysfs_open_dirent;
85a4ffad TH	17
59f69015	18	/* type-specific structures for sysfs_dirent->s_* union members */
3e519038	19	struct sysfs_elem_dir {
59f69015	20	struct kobject *kobj;
7f9838fd	21
54d20f00	22	unsigned long subdirs;
4e4d6d86 EB	23	/* children rbtree starts here and goes through sd->s_rb */
4e4d6d86 EB	24	struct rb_root children;
3e519038 TH	25	};
	26
	27	struct sysfs_elem_symlink {
59f69015	28	struct sysfs_dirent *target_sd;
3e519038 TH	29	};
	30
	31	struct sysfs_elem_attr {
56b3f3b8 TH	32	union {
	33	struct attribute *attr;
	34	struct bin_attribute *bin_attr;
	35	};
85a4ffad	36	struct sysfs_open_dirent *open;
3e519038 TH	37	};
3e519038 TH	38
ddd29ec6 DQ	39	struct sysfs_inode_attrs {
	40	struct iattr ia_iattr;
	41	void *ia_secdata;
	42	u32 ia_secdata_len;
	43	};
	44
0ab66088	45	/*
59f69015 TH	46	* sysfs_dirent - the building block of sysfs hierarchy. Each and
	47	* every sysfs node is represented by single sysfs_dirent.
	48	*
0ab66088 TH	49	* As long as s_count reference is held, the sysfs_dirent itself is
	50	* accessible. Dereferencing s_elem or any other outer entity
	51	* requires s_active reference.
	52	*/
d56c3eae AR	53	struct sysfs_dirent {
d56c3eae AR	54	atomic_t s_count;
8619f979	55	atomic_t s_active;
846f9974 EB	56	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	57	struct lockdep_map dep_map;
	58	#endif
59f69015	59	struct sysfs_dirent *s_parent;
59f69015	60	const char *s_name;
3e519038	61
4e4d6d86	62	struct rb_node s_rb;
4f72c0ca	63
58f2a4c7 MP	64	union {
	65	struct completion *completion;
	66	struct sysfs_dirent *removed_list;
	67	} u;
	68
be867b19	69	const void s_ns; / namespace tag */
4e4d6d86	70	unsigned int s_hash; /* ns + name hash */
3e519038	71	union {
b1fc3d61 TH	72	struct sysfs_elem_dir s_dir;
	73	struct sysfs_elem_symlink s_symlink;
	74	struct sysfs_elem_attr s_attr;
b1fc3d61	75	};
3e519038	76
15a33824	77	unsigned short s_flags;
2c3a908b	78	umode_t s_mode;
cafa6b5d	79	unsigned int s_ino;
ddd29ec6	80	struct sysfs_inode_attrs *s_iattr;
d56c3eae	81	};
1da177e4	82
59f69015	83	#define SD_DEACTIVATED_BIAS INT_MIN
0ab66088	84
59f69015	85	#define SYSFS_TYPE_MASK 0x00ff
dc2f75f0 TH	86	#define SYSFS_DIR 0x0001
	87	#define SYSFS_KOBJ_ATTR 0x0002
	88	#define SYSFS_KOBJ_BIN_ATTR 0x0004
	89	#define SYSFS_KOBJ_LINK 0x0008
59f69015	90	#define SYSFS_COPY_NAME (SYSFS_DIR \| SYSFS_KOBJ_LINK)
a2db6842	91	#define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR \| SYSFS_KOBJ_BIN_ATTR)
59f69015	92
cb26a311 TH	93	#define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK
cb26a311 TH	94	#define SYSFS_FLAG_HAS_NS 0x01000
15a33824	95	#define SYSFS_FLAG_REMOVED 0x02000
59f69015 TH	96
	97	static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
	98	{
	99	return sd->s_flags & SYSFS_TYPE_MASK;
	100	}
	101
846f9974	102	#ifdef CONFIG_DEBUG_LOCK_ALLOC
785a162d	103
846f9974 EB	104	#define sysfs_dirent_init_lockdep(sd) \
846f9974 EB	105	do { \
6992f533 EB	106	struct attribute *attr = sd->s_attr.attr; \
	107	struct lock_class_key *key = attr->key; \
	108	if (!key) \
	109	key = &attr->skey; \
846f9974	110	\
6992f533	111	lockdep_init_map(&sd->dep_map, "s_active", key, 0); \
2c3a908b	112	} while (0)
785a162d TH	113
	114	/* Test for attributes that want to ignore lockdep for read-locking */
	115	static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
	116	{
672f76a8 TH	117	int type = sysfs_type(sd);
	118
	119	return (type == SYSFS_KOBJ_ATTR \|\| type == SYSFS_KOBJ_BIN_ATTR) &&
785a162d TH	120	sd->s_attr.attr->ignore_lockdep;
	121	}
	122
846f9974	123	#else
785a162d	124
2c3a908b	125	#define sysfs_dirent_init_lockdep(sd) do {} while (0)
785a162d TH	126
	127	static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
	128	{
	129	return true;
	130	}
	131
846f9974 EB	132	#endif
846f9974 EB	133
59f69015 TH	134	/*
	135	* Context structure to be used while adding/removing nodes.
	136	*/
fb6896da	137	struct sysfs_addrm_cxt {
fb6896da	138	struct sysfs_dirent *removed;
fb6896da TH	139	};
fb6896da TH	140
59f69015 TH	141	/*
	142	* mount.c
	143	*/
be867b19 SH	144
be867b19 SH	145	/*
cb26a311 TH	146	* Each sb is associated with one namespace tag, currently the network
	147	* namespace of the task which mounted this sysfs instance. If multiple
	148	* tags become necessary, make the following an array and compare
	149	* sysfs_dirent tag against every entry.
be867b19	150	*/
9e7fdd25	151	struct sysfs_super_info {
cb26a311	152	void *ns;
9e7fdd25 EB	153	};
9e7fdd25 EB	154	#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
51225039	155	extern struct sysfs_dirent sysfs_root;
e18b890b	156	extern struct kmem_cache *sysfs_dir_cachep;
1da177e4	157
59f69015 TH	158	/*
	159	* dir.c
	160	*/
3007e997	161	extern struct mutex sysfs_mutex;
59f69015	162	extern spinlock_t sysfs_assoc_lock;
469796d1	163	extern const struct dentry_operations sysfs_dentry_ops;
59f69015	164
4b6f5d20	165	extern const struct file_operations sysfs_dir_operations;
c5ef1c42	166	extern const struct inode_operations sysfs_dir_inode_operations;
1da177e4	167
e72ceb8c EB	168	struct sysfs_dirent sysfs_get_active(struct sysfs_dirent sd);
e72ceb8c EB	169	void sysfs_put_active(struct sysfs_dirent *sd);
d69ac5a0	170	void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt);
d1c1459e	171	void sysfs_warn_dup(struct sysfs_dirent parent, const char name);
d69ac5a0 TH	172	int __sysfs_add_one(struct sysfs_addrm_cxt acxt, struct sysfs_dirent sd,
	173	struct sysfs_dirent *parent_sd);
	174	int sysfs_add_one(struct sysfs_addrm_cxt acxt, struct sysfs_dirent sd,
	175	struct sysfs_dirent *parent_sd);
250f7c3f	176	void sysfs_remove(struct sysfs_dirent *sd);
7eed6ecb TH	177	int sysfs_hash_and_remove(struct sysfs_dirent dir_sd, const char name,
7eed6ecb TH	178	const void *ns);
59f69015 TH	179	void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
	180
	181	struct sysfs_dirent sysfs_find_dirent(struct sysfs_dirent parent_sd,
cfec0bc8 TH	182	const unsigned char *name,
cfec0bc8 TH	183	const void *ns);
59f69015 TH	184	struct sysfs_dirent sysfs_new_dirent(const char name, umode_t mode, int type);
	185
	186	void release_sysfs_dirent(struct sysfs_dirent *sd);
	187
	188	int sysfs_create_subdir(struct kobject kobj, const char name,
	189	struct sysfs_dirent **p_sd);
59f69015	190
2c3a908b	191	int sysfs_rename(struct sysfs_dirent sd, struct sysfs_dirent new_parent_sd,
cfec0bc8	192	const char new_name, const void new_ns);
ca1bab38	193
f1282c84	194	static inline struct sysfs_dirent __sysfs_get(struct sysfs_dirent sd)
1da177e4	195	{
0ab66088 TH	196	if (sd) {
	197	WARN_ON(!atomic_read(&sd->s_count));
	198	atomic_inc(&sd->s_count);
	199	}
	200	return sd;
1da177e4	201	}
f1282c84	202	#define sysfs_get(sd) __sysfs_get(sd)
1da177e4	203
f1282c84	204	static inline void __sysfs_put(struct sysfs_dirent *sd)
1da177e4	205	{
0ab66088 TH	206	if (sd && atomic_dec_and_test(&sd->s_count))
	207	release_sysfs_dirent(sd);
	208	}
f1282c84	209	#define sysfs_put(sd) __sysfs_put(sd)
59f69015 TH	210
	211	/*
	212	* inode.c
	213	*/
fac2622b	214	struct inode sysfs_get_inode(struct super_block sb, struct sysfs_dirent *sd);
01cd9fef	215	void sysfs_evict_inode(struct inode *inode);
35df63c4	216	int sysfs_sd_setattr(struct sysfs_dirent sd, struct iattr iattr);
10556cb2	217	int sysfs_permission(struct inode *inode, int mask);
59f69015	218	int sysfs_setattr(struct dentry dentry, struct iattr iattr);
2c3a908b GKH	219	int sysfs_getattr(struct vfsmount mnt, struct dentry dentry,
2c3a908b GKH	220	struct kstat *stat);
ddd29ec6	221	int sysfs_setxattr(struct dentry dentry, const char name, const void *value,
2c3a908b	222	size_t size, int flags);
e0bf68dd	223	int sysfs_inode_init(void);
59f69015 TH	224
	225	/*
	226	* file.c
	227	*/
	228	extern const struct file_operations sysfs_file_operations;
f9b9a621	229	extern const struct file_operations sysfs_bin_operations;
59f69015 TH	230
	231	int sysfs_add_file(struct sysfs_dirent *dir_sd,
	232	const struct attribute *attr, int type);
	233
58292cbe TH	234	int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
	235	const struct attribute *attr, int type,
	236	umode_t amode, const void *ns);
73d97146 TH	237	void sysfs_unmap_bin_file(struct sysfs_dirent *sd);
73d97146 TH	238
59f69015 TH	239	/*
	240	* symlink.c
	241	*/
	242	extern const struct inode_operations sysfs_symlink_inode_operations;
0bb8f3d6 RW	243	int sysfs_create_link_sd(struct sysfs_dirent sd, struct kobject target,
0bb8f3d6 RW	244	const char *name);