[linux-2.6-block.git] / fs / f2fs / xattr.h

/*
 * fs/f2fs/xattr.h
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 *
 * Portions of this code from linux/fs/ext2/xattr.h
 *
 * On-disk format of extended attributes for the ext2 filesystem.
 *
 * (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef __F2FS_XATTR_H__
#define __F2FS_XATTR_H__

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

/* Magic value in attribute blocks */
#define F2FS_XATTR_MAGIC                0xF2F52011

/* Maximum number of references to one attribute block */
#define F2FS_XATTR_REFCOUNT_MAX         1024

/* Name indexes */
#define F2FS_SYSTEM_ADVISE_PREFIX		"system.advise"
#define F2FS_XATTR_INDEX_USER			1
#define F2FS_XATTR_INDEX_POSIX_ACL_ACCESS	2
#define F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT	3
#define F2FS_XATTR_INDEX_TRUSTED		4
#define F2FS_XATTR_INDEX_LUSTRE			5
#define F2FS_XATTR_INDEX_SECURITY		6
#define F2FS_XATTR_INDEX_ADVISE			7

struct f2fs_xattr_header {
	__le32  h_magic;        /* magic number for identification */
	__le32  h_refcount;     /* reference count */
	__u32   h_reserved[4];  /* zero right now */
};

struct f2fs_xattr_entry {
	__u8    e_name_index;
	__u8    e_name_len;
	__le16  e_value_size;   /* size of attribute value */
	char    e_name[0];      /* attribute name */
};

#define XATTR_HDR(ptr)		((struct f2fs_xattr_header *)(ptr))
#define XATTR_ENTRY(ptr)	((struct f2fs_xattr_entry *)(ptr))
#define XATTR_FIRST_ENTRY(ptr)	(XATTR_ENTRY(XATTR_HDR(ptr)+1))
#define XATTR_ROUND		(3)

#define XATTR_ALIGN(size)	((size + XATTR_ROUND) & ~XATTR_ROUND)

#define ENTRY_SIZE(entry) (XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + \
			entry->e_name_len + le16_to_cpu(entry->e_value_size)))

#define XATTR_NEXT_ENTRY(entry)	((struct f2fs_xattr_entry *)((char *)(entry) +\
			ENTRY_SIZE(entry)))

#define IS_XATTR_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)

#define list_for_each_xattr(entry, addr) \
		for (entry = XATTR_FIRST_ENTRY(addr);\
				!IS_XATTR_LAST_ENTRY(entry);\
				entry = XATTR_NEXT_ENTRY(entry))


#define MIN_OFFSET	XATTR_ALIGN(PAGE_SIZE - \
			sizeof(struct node_footer) - \
			sizeof(__u32))

#define MAX_VALUE_LEN	(MIN_OFFSET - sizeof(struct f2fs_xattr_header) - \
			sizeof(struct f2fs_xattr_entry))

/*
 * On-disk structure of f2fs_xattr
 * We use only 1 block for xattr.
 *
 * +--------------------+
 * | f2fs_xattr_header  |
 * |                    |
 * +--------------------+
 * | f2fs_xattr_entry   |
 * | .e_name_index = 1  |
 * | .e_name_len = 3    |
 * | .e_value_size = 14 |
 * | .e_name = "foo"    |
 * | "value_of_xattr"   |<- value_offs = e_name + e_name_len
 * +--------------------+
 * | f2fs_xattr_entry   |
 * | .e_name_index = 4  |
 * | .e_name = "bar"    |
 * +--------------------+
 * |                    |
 * |        Free        |
 * |                    |
 * +--------------------+<- MIN_OFFSET
 * |   node_footer      |
 * | (nid, ino, offset) |
 * +--------------------+
 *
 **/

#ifdef CONFIG_F2FS_FS_XATTR
extern const struct xattr_handler f2fs_xattr_user_handler;
extern const struct xattr_handler f2fs_xattr_trusted_handler;
extern const struct xattr_handler f2fs_xattr_acl_access_handler;
extern const struct xattr_handler f2fs_xattr_acl_default_handler;
extern const struct xattr_handler f2fs_xattr_advise_handler;
extern const struct xattr_handler f2fs_xattr_security_handler;

extern const struct xattr_handler *f2fs_xattr_handlers[];

extern int f2fs_setxattr(struct inode *, int, const char *,
				const void *, size_t, struct page *);
extern int f2fs_getxattr(struct inode *, int, const char *, void *, size_t);
extern ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
#else

#define f2fs_xattr_handlers	NULL
static inline int f2fs_setxattr(struct inode *inode, int name_index,
		const char *name, const void *value, size_t value_len)
{
	return -EOPNOTSUPP;
}
static inline int f2fs_getxattr(struct inode *inode, int name_index,
		const char *name, void *buffer, size_t buffer_size)
{
	return -EOPNOTSUPP;
}
static inline ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer,
		size_t buffer_size)
{
	return -EOPNOTSUPP;
}
#endif

#ifdef CONFIG_F2FS_FS_SECURITY
extern int f2fs_init_security(struct inode *, struct inode *,
				const struct qstr *, struct page *);
#else
static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
				const struct qstr *qstr, struct page *ipage)
{
	return 0;
}
#endif
#endif /* __F2FS_XATTR_H__ */
Commit	Line	Data
0a8165d7	1	/*
af48b85b JK	2	* fs/f2fs/xattr.h
	3	*
	4	* Copyright (c) 2012 Samsung Electronics Co., Ltd.
	5	* http://www.samsung.com/
	6	*
	7	* Portions of this code from linux/fs/ext2/xattr.h
	8	*
	9	* On-disk format of extended attributes for the ext2 filesystem.
	10	*
	11	* (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License version 2 as
	15	* published by the Free Software Foundation.
	16	*/
	17	#ifndef __F2FS_XATTR_H__
	18	#define __F2FS_XATTR_H__
	19
	20	#include <linux/init.h>
	21	#include <linux/xattr.h>
	22
	23	/* Magic value in attribute blocks */
	24	#define F2FS_XATTR_MAGIC 0xF2F52011
	25
	26	/* Maximum number of references to one attribute block */
	27	#define F2FS_XATTR_REFCOUNT_MAX 1024
	28
	29	/* Name indexes */
	30	#define F2FS_SYSTEM_ADVISE_PREFIX "system.advise"
	31	#define F2FS_XATTR_INDEX_USER 1
	32	#define F2FS_XATTR_INDEX_POSIX_ACL_ACCESS 2
	33	#define F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT 3
	34	#define F2FS_XATTR_INDEX_TRUSTED 4
	35	#define F2FS_XATTR_INDEX_LUSTRE 5
	36	#define F2FS_XATTR_INDEX_SECURITY 6
	37	#define F2FS_XATTR_INDEX_ADVISE 7
	38
	39	struct f2fs_xattr_header {
	40	__le32 h_magic; /* magic number for identification */
	41	__le32 h_refcount; /* reference count */
	42	__u32 h_reserved[4]; /* zero right now */
	43	};
	44
	45	struct f2fs_xattr_entry {
	46	__u8 e_name_index;
	47	__u8 e_name_len;
	48	__le16 e_value_size; /* size of attribute value */
	49	char e_name[0]; /* attribute name */
	50	};
	51
	52	#define XATTR_HDR(ptr) ((struct f2fs_xattr_header *)(ptr))
	53	#define XATTR_ENTRY(ptr) ((struct f2fs_xattr_entry *)(ptr))
	54	#define XATTR_FIRST_ENTRY(ptr) (XATTR_ENTRY(XATTR_HDR(ptr)+1))
	55	#define XATTR_ROUND (3)
	56
	57	#define XATTR_ALIGN(size) ((size + XATTR_ROUND) & ~XATTR_ROUND)
	58
	59	#define ENTRY_SIZE(entry) (XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + \
	60	entry->e_name_len + le16_to_cpu(entry->e_value_size)))
	61
	62	#define XATTR_NEXT_ENTRY(entry) ((struct f2fs_xattr_entry )((char )(entry) +\
	63	ENTRY_SIZE(entry)))
	64
	65	#define IS_XATTR_LAST_ENTRY(entry) ((__u32 )(entry) == 0)
66
67	#define list_for_each_xattr(entry, addr) \
68	for (entry = XATTR_FIRST_ENTRY(addr);\
69	!IS_XATTR_LAST_ENTRY(entry);\
70	entry = XATTR_NEXT_ENTRY(entry))
71
72
73	#define MIN_OFFSET XATTR_ALIGN(PAGE_SIZE - \
74	sizeof(struct node_footer) - \
75	sizeof(__u32))
76
77	#define MAX_VALUE_LEN (MIN_OFFSET - sizeof(struct f2fs_xattr_header) - \
78	sizeof(struct f2fs_xattr_entry))
79
0a8165d7	80	/*
af48b85b JK	81	* On-disk structure of f2fs_xattr
	82	* We use only 1 block for xattr.
	83	*
	84	* +--------------------+
	85	* \| f2fs_xattr_header \|
	86	* \| \|
	87	* +--------------------+
	88	* \| f2fs_xattr_entry \|
	89	* \| .e_name_index = 1 \|
	90	* \| .e_name_len = 3 \|
	91	* \| .e_value_size = 14 \|
	92	* \| .e_name = "foo" \|
	93	* \| "value_of_xattr" \|<- value_offs = e_name + e_name_len
	94	* +--------------------+
	95	* \| f2fs_xattr_entry \|
	96	* \| .e_name_index = 4 \|
	97	* \| .e_name = "bar" \|
	98	* +--------------------+
	99	* \| \|
	100	* \| Free \|
	101	* \| \|
	102	* +--------------------+<- MIN_OFFSET
	103	* \| node_footer \|
	104	* \| (nid, ino, offset) \|
	105	* +--------------------+
	106	*
	107	**/
	108
	109	#ifdef CONFIG_F2FS_FS_XATTR
	110	extern const struct xattr_handler f2fs_xattr_user_handler;
	111	extern const struct xattr_handler f2fs_xattr_trusted_handler;
	112	extern const struct xattr_handler f2fs_xattr_acl_access_handler;
	113	extern const struct xattr_handler f2fs_xattr_acl_default_handler;
	114	extern const struct xattr_handler f2fs_xattr_advise_handler;
8ae8f162	115	extern const struct xattr_handler f2fs_xattr_security_handler;
af48b85b JK	116
	117	extern const struct xattr_handler *f2fs_xattr_handlers[];
	118
8ae8f162 JK	119	extern int f2fs_setxattr(struct inode , int, const char ,
	120	const void , size_t, struct page );
	121	extern int f2fs_getxattr(struct inode , int, const char , void *, size_t);
	122	extern ssize_t f2fs_listxattr(struct dentry , char , size_t);
af48b85b JK	123	#else
	124
	125	#define f2fs_xattr_handlers NULL
	126	static inline int f2fs_setxattr(struct inode *inode, int name_index,
8ae8f162	127	const char name, const void value, size_t value_len)
af48b85b JK	128	{
	129	return -EOPNOTSUPP;
	130	}
	131	static inline int f2fs_getxattr(struct inode *inode, int name_index,
	132	const char name, void buffer, size_t buffer_size)
	133	{
	134	return -EOPNOTSUPP;
	135	}
	136	static inline ssize_t f2fs_listxattr(struct dentry dentry, char buffer,
	137	size_t buffer_size)
	138	{
	139	return -EOPNOTSUPP;
	140	}
	141	#endif
	142
8ae8f162 JK	143	#ifdef CONFIG_F2FS_FS_SECURITY
	144	extern int f2fs_init_security(struct inode , struct inode ,
	145	const struct qstr , struct page );
	146	#else
	147	static inline int f2fs_init_security(struct inode inode, struct inode dir,
	148	const struct qstr qstr, struct page ipage)
	149	{
	150	return 0;
	151	}
	152	#endif
af48b85b	153	#endif /* __F2FS_XATTR_H__ */