summaryrefslogtreecommitdiffstats
path: root/fs/f2fs/xattr.h
blob: dbcd1d16e66982e07233e66fe400e95597a6c2df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*
 * 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_NAME			"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
/* Should be same as EXT4_XATTR_INDEX_ENCRYPTION */
#define F2FS_XATTR_INDEX_ENCRYPTION		9

#define F2FS_XATTR_NAME_ENCRYPTION_CONTEXT	"c"

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 VALID_XATTR_BLOCK_SIZE	(PAGE_SIZE - sizeof(struct node_footer))
#define XATTR_PADDING_SIZE	(sizeof(__u32))
#define MIN_OFFSET(i)		XATTR_ALIGN(inline_xattr_size(i) +	\
						VALID_XATTR_BLOCK_SIZE)

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

/*
 * On-disk structure of f2fs_xattr
 * We use inline xattrs space + 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_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 *, int);
extern int f2fs_getxattr(struct inode *, int, const char *, void *,
						size_t, struct page *);
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 index,
		const char *name, const void *value, size_t size,
		struct page *page, int flags)
{
	return -EOPNOTSUPP;
}
static inline int f2fs_getxattr(struct inode *inode, int index,
			const char *name, void *buffer,
			size_t buffer_size, struct page *dpage)
{
	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__ */
OpenPOWER on IntegriCloud