[linux-block.git] / fs / configfs / configfs_internal.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * 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)
#define CONFIGFS_PINNED \
	(CONFIGFS_ROOT | CONFIGFS_DIR | CONFIGFS_ITEM_LINK)

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 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 mnt_idmap *idmap,
			    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 mnt_idmap *idmap,
			    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);
}
Commit	Line	Data
	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
	2	/*
	3	* configfs_internal.h - Internal stuff for configfs
	4	*
	5	* Based on sysfs:
	6	* sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
	7	*
	8	* configfs Copyright (C) 2005 Oracle. All rights reserved.
	9	*/
	10
	11	#ifdef pr_fmt
	12	#undef pr_fmt
	13	#endif
	14
	15	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	16
	17	#include <linux/slab.h>
	18	#include <linux/list.h>
	19	#include <linux/spinlock.h>
	20
	21	struct configfs_fragment {
	22	atomic_t frag_count;
	23	struct rw_semaphore frag_sem;
	24	bool frag_dead;
	25	};
	26
	27	void put_fragment(struct configfs_fragment *);
	28	struct configfs_fragment get_fragment(struct configfs_fragment );
	29
	30	struct configfs_dirent {
	31	atomic_t s_count;
	32	int s_dependent_count;
	33	struct list_head s_sibling;
	34	struct list_head s_children;
	35	int s_links;
	36	void * s_element;
	37	int s_type;
	38	umode_t s_mode;
	39	struct dentry * s_dentry;
	40	struct iattr * s_iattr;
	41	#ifdef CONFIG_LOCKDEP
	42	int s_depth;
	43	#endif
	44	struct configfs_fragment *s_frag;
	45	};
	46
	47	#define CONFIGFS_ROOT 0x0001
	48	#define CONFIGFS_DIR 0x0002
	49	#define CONFIGFS_ITEM_ATTR 0x0004
	50	#define CONFIGFS_ITEM_BIN_ATTR 0x0008
	51	#define CONFIGFS_ITEM_LINK 0x0020
	52	#define CONFIGFS_USET_DIR 0x0040
	53	#define CONFIGFS_USET_DEFAULT 0x0080
	54	#define CONFIGFS_USET_DROPPING 0x0100
	55	#define CONFIGFS_USET_IN_MKDIR 0x0200
	56	#define CONFIGFS_USET_CREATING 0x0400
	57	#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR \| CONFIGFS_ITEM_BIN_ATTR)
	58	#define CONFIGFS_PINNED \
	59	(CONFIGFS_ROOT \| CONFIGFS_DIR \| CONFIGFS_ITEM_LINK)
	60
	61	extern struct mutex configfs_symlink_mutex;
	62	extern spinlock_t configfs_dirent_lock;
	63
	64	extern struct kmem_cache *configfs_dir_cachep;
	65
	66	extern int configfs_is_root(struct config_item *item);
	67
	68	extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent , struct super_block );
	69	extern struct inode configfs_create(struct dentry , umode_t mode);
	70
	71	extern int configfs_create_file(struct config_item , const struct configfs_attribute );
	72	extern int configfs_create_bin_file(struct config_item *,
	73	const struct configfs_bin_attribute *);
	74	extern int configfs_make_dirent(struct configfs_dirent , struct dentry ,
	75	void , umode_t, int, struct configfs_fragment );
	76	extern int configfs_dirent_is_ready(struct configfs_dirent *);
	77
	78	extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);
	79	extern void configfs_drop_dentry(struct configfs_dirent sd, struct dentry parent);
	80	extern int configfs_setattr(struct mnt_idmap *idmap,
	81	struct dentry dentry, struct iattr iattr);
	82
	83	extern struct dentry *configfs_pin_fs(void);
	84	extern void configfs_release_fs(void);
	85
	86	extern const struct file_operations configfs_dir_operations;
	87	extern const struct file_operations configfs_file_operations;
	88	extern const struct file_operations configfs_bin_file_operations;
	89	extern const struct inode_operations configfs_dir_inode_operations;
	90	extern const struct inode_operations configfs_root_inode_operations;
	91	extern const struct inode_operations configfs_symlink_inode_operations;
	92	extern const struct dentry_operations configfs_dentry_ops;
	93
	94	extern int configfs_symlink(struct mnt_idmap *idmap,
	95	struct inode dir, struct dentry dentry,
	96	const char *symname);
	97	extern int configfs_unlink(struct inode dir, struct dentry dentry);
	98
	99	int configfs_create_link(struct configfs_dirent target, struct dentry parent,
	100	struct dentry dentry, char body);
	101
	102	static inline struct config_item * to_item(struct dentry * dentry)
	103	{
	104	struct configfs_dirent * sd = dentry->d_fsdata;
	105	return ((struct config_item *) sd->s_element);
	106	}
	107
	108	static inline struct configfs_attribute * to_attr(struct dentry * dentry)
	109	{
	110	struct configfs_dirent * sd = dentry->d_fsdata;
	111	return ((struct configfs_attribute *) sd->s_element);
	112	}
	113
	114	static inline struct configfs_bin_attribute to_bin_attr(struct dentry dentry)
	115	{
	116	struct configfs_attribute *attr = to_attr(dentry);
	117
	118	return container_of(attr, struct configfs_bin_attribute, cb_attr);
	119	}
	120
	121	static inline struct config_item configfs_get_config_item(struct dentry dentry)
	122	{
	123	struct config_item * item = NULL;
	124
	125	spin_lock(&dentry->d_lock);
	126	if (!d_unhashed(dentry)) {
	127	struct configfs_dirent * sd = dentry->d_fsdata;
	128	item = config_item_get(sd->s_element);
	129	}
	130	spin_unlock(&dentry->d_lock);
	131
	132	return item;
	133	}
	134
	135	static inline void release_configfs_dirent(struct configfs_dirent * sd)
	136	{
	137	if (!(sd->s_type & CONFIGFS_ROOT)) {
	138	kfree(sd->s_iattr);
	139	put_fragment(sd->s_frag);
	140	kmem_cache_free(configfs_dir_cachep, sd);
	141	}
	142	}
	143
	144	static inline struct configfs_dirent * configfs_get(struct configfs_dirent * sd)
	145	{
	146	if (sd) {
	147	WARN_ON(!atomic_read(&sd->s_count));
	148	atomic_inc(&sd->s_count);
	149	}
	150	return sd;
	151	}
	152
	153	static inline void configfs_put(struct configfs_dirent * sd)
	154	{
	155	WARN_ON(!atomic_read(&sd->s_count));
	156	if (atomic_dec_and_test(&sd->s_count))
	157	release_configfs_dirent(sd);
	158	}
	159