[mirror_ubuntu-artful-kernel.git] / fs / ext2 / xattr.h

/*
  File: linux/ext2_xattr.h

  On-disk format of extended attributes for the ext2 filesystem.

  (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/

#include <linux/init.h>
#include <linux/xattr.h>

/* Magic value in attribute blocks */
#define EXT2_XATTR_MAGIC		0xEA020000

/* Maximum number of references to one attribute block */
#define EXT2_XATTR_REFCOUNT_MAX		1024

/* Name indexes */
#define EXT2_XATTR_INDEX_USER			1
#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS	2
#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT	3
#define EXT2_XATTR_INDEX_TRUSTED		4
#define	EXT2_XATTR_INDEX_LUSTRE			5
#define EXT2_XATTR_INDEX_SECURITY	        6

struct ext2_xattr_header {
	__le32	h_magic;	/* magic number for identification */
	__le32	h_refcount;	/* reference count */
	__le32	h_blocks;	/* number of disk blocks used */
	__le32	h_hash;		/* hash value of all attributes */
	__u32	h_reserved[4];	/* zero right now */
};

struct ext2_xattr_entry {
	__u8	e_name_len;	/* length of name */
	__u8	e_name_index;	/* attribute name index */
	__le16	e_value_offs;	/* offset in disk block of value */
	__le32	e_value_block;	/* disk block attribute is stored on (n/i) */
	__le32	e_value_size;	/* size of attribute value */
	__le32	e_hash;		/* hash value of name and value */
	char	e_name[0];	/* attribute name */
};

#define EXT2_XATTR_PAD_BITS		2
#define EXT2_XATTR_PAD		(1<<EXT2_XATTR_PAD_BITS)
#define EXT2_XATTR_ROUND		(EXT2_XATTR_PAD-1)
#define EXT2_XATTR_LEN(name_len) \
	(((name_len) + EXT2_XATTR_ROUND + \
	sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
#define EXT2_XATTR_NEXT(entry) \
	( (struct ext2_xattr_entry *)( \
	  (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
#define EXT2_XATTR_SIZE(size) \
	(((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)

struct mb_cache;

# ifdef CONFIG_EXT2_FS_XATTR

extern const struct xattr_handler ext2_xattr_user_handler;
extern const struct xattr_handler ext2_xattr_trusted_handler;
extern const struct xattr_handler ext2_xattr_security_handler;

extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);

extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);
extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);

extern void ext2_xattr_delete_inode(struct inode *);

extern struct mb_cache *ext2_xattr_create_cache(void);
extern void ext2_xattr_destroy_cache(struct mb_cache *cache);

extern const struct xattr_handler *ext2_xattr_handlers[];

# else  /* CONFIG_EXT2_FS_XATTR */

static inline int
ext2_xattr_get(struct inode *inode, int name_index,
	       const char *name, void *buffer, size_t size)
{
	return -EOPNOTSUPP;
}

static inline int
ext2_xattr_set(struct inode *inode, int name_index, const char *name,
	       const void *value, size_t size, int flags)
{
	return -EOPNOTSUPP;
}

static inline void
ext2_xattr_delete_inode(struct inode *inode)
{
}

static inline void ext2_xattr_destroy_cache(struct mb_cache *cache)
{
}

#define ext2_xattr_handlers NULL

# endif  /* CONFIG_EXT2_FS_XATTR */

#ifdef CONFIG_EXT2_FS_SECURITY
extern int ext2_init_security(struct inode *inode, struct inode *dir,
			      const struct qstr *qstr);
#else
static inline int ext2_init_security(struct inode *inode, struct inode *dir,
				     const struct qstr *qstr)
{
	return 0;
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	File: linux/ext2_xattr.h
	3
	4	On-disk format of extended attributes for the ext2 filesystem.
	5
	6	(C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
	7	*/
	8
1da177e4 LT	9	#include <linux/init.h>
	10	#include <linux/xattr.h>
	11
	12	/* Magic value in attribute blocks */
	13	#define EXT2_XATTR_MAGIC 0xEA020000
	14
	15	/* Maximum number of references to one attribute block */
	16	#define EXT2_XATTR_REFCOUNT_MAX 1024
	17
	18	/* Name indexes */
	19	#define EXT2_XATTR_INDEX_USER 1
	20	#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
	21	#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
	22	#define EXT2_XATTR_INDEX_TRUSTED 4
	23	#define EXT2_XATTR_INDEX_LUSTRE 5
	24	#define EXT2_XATTR_INDEX_SECURITY 6
	25
	26	struct ext2_xattr_header {
	27	__le32 h_magic; /* magic number for identification */
	28	__le32 h_refcount; /* reference count */
	29	__le32 h_blocks; /* number of disk blocks used */
	30	__le32 h_hash; /* hash value of all attributes */
	31	__u32 h_reserved[4]; /* zero right now */
	32	};
	33
	34	struct ext2_xattr_entry {
	35	__u8 e_name_len; /* length of name */
	36	__u8 e_name_index; /* attribute name index */
	37	__le16 e_value_offs; /* offset in disk block of value */
	38	__le32 e_value_block; /* disk block attribute is stored on (n/i) */
	39	__le32 e_value_size; /* size of attribute value */
	40	__le32 e_hash; /* hash value of name and value */
	41	char e_name[0]; /* attribute name */
	42	};
	43
	44	#define EXT2_XATTR_PAD_BITS 2
	45	#define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)
	46	#define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)
	47	#define EXT2_XATTR_LEN(name_len) \
	48	(((name_len) + EXT2_XATTR_ROUND + \
	49	sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
	50	#define EXT2_XATTR_NEXT(entry) \
	51	( (struct ext2_xattr_entry *)( \
	52	(char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
	53	#define EXT2_XATTR_SIZE(size) \
	54	(((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)
	55
7a2508e1	56	struct mb_cache;
be0726d3	57
1da177e4 LT	58	# ifdef CONFIG_EXT2_FS_XATTR
1da177e4 LT	59
749c72ef SH	60	extern const struct xattr_handler ext2_xattr_user_handler;
749c72ef SH	61	extern const struct xattr_handler ext2_xattr_trusted_handler;
749c72ef	62	extern const struct xattr_handler ext2_xattr_security_handler;
1da177e4 LT	63
	64	extern ssize_t ext2_listxattr(struct dentry , char , size_t);
	65
	66	extern int ext2_xattr_get(struct inode , int, const char , void *, size_t);
	67	extern int ext2_xattr_set(struct inode , int, const char , const void *, size_t, int);
	68
	69	extern void ext2_xattr_delete_inode(struct inode *);
1da177e4	70
7a2508e1 JK	71	extern struct mb_cache *ext2_xattr_create_cache(void);
7a2508e1 JK	72	extern void ext2_xattr_destroy_cache(struct mb_cache *cache);
1da177e4	73
749c72ef	74	extern const struct xattr_handler *ext2_xattr_handlers[];
1da177e4 LT	75
	76	# else /* CONFIG_EXT2_FS_XATTR */
	77
	78	static inline int
	79	ext2_xattr_get(struct inode *inode, int name_index,
	80	const char name, void buffer, size_t size)
	81	{
	82	return -EOPNOTSUPP;
	83	}
	84
	85	static inline int
	86	ext2_xattr_set(struct inode inode, int name_index, const char name,
	87	const void *value, size_t size, int flags)
	88	{
	89	return -EOPNOTSUPP;
	90	}
	91
	92	static inline void
	93	ext2_xattr_delete_inode(struct inode *inode)
	94	{
	95	}
	96
7a2508e1	97	static inline void ext2_xattr_destroy_cache(struct mb_cache *cache)
1da177e4 LT	98	{
	99	}
	100
	101	#define ext2_xattr_handlers NULL
	102
	103	# endif /* CONFIG_EXT2_FS_XATTR */
	104
10f47e6a	105	#ifdef CONFIG_EXT2_FS_SECURITY
2a7dba39 EP	106	extern int ext2_init_security(struct inode inode, struct inode dir,
2a7dba39 EP	107	const struct qstr *qstr);
10f47e6a	108	#else
2a7dba39 EP	109	static inline int ext2_init_security(struct inode inode, struct inode dir,
2a7dba39 EP	110	const struct qstr *qstr)
10f47e6a SS	111	{
	112	return 0;
	113	}
	114	#endif