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gerrit.nordix.org / codeaurora / cp-linux / 8d8f6542b666daf5e87de156590e635c2c4da0c0 / . / fs / ext4 / xattr.h
blob: ddc0957760ba00797aa90906efaad5d4e54e7c36 [file] [log] [blame]
Kyle Swenson8d8f6542021-03-15 11:02:55 -0600[diff] [blame^]1/*
2 File: fs/ext4/xattr.h
3
4 On-disk format of extended attributes for the ext4 filesystem.
5
6 (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
7*/
8
9#include <linux/xattr.h>
10
11/* Magic value in attribute blocks */
12#define EXT4_XATTR_MAGIC 0xEA020000
13
14/* Maximum number of references to one attribute block */
15#define EXT4_XATTR_REFCOUNT_MAX 1024
16
17/* Name indexes */
18#define EXT4_XATTR_INDEX_USER 1
19#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2
20#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3
21#define EXT4_XATTR_INDEX_TRUSTED 4
22#define EXT4_XATTR_INDEX_LUSTRE 5
23#define EXT4_XATTR_INDEX_SECURITY 6
24#define EXT4_XATTR_INDEX_SYSTEM 7
25#define EXT4_XATTR_INDEX_RICHACL 8
26#define EXT4_XATTR_INDEX_ENCRYPTION 9
27
28struct ext4_xattr_header {
29 __le32 h_magic; /* magic number for identification */
30 __le32 h_refcount; /* reference count */
31 __le32 h_blocks; /* number of disk blocks used */
32 __le32 h_hash; /* hash value of all attributes */
33 __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */
34 /* id = inum if refcount=1, blknum otherwise */
35 __u32 h_reserved[3]; /* zero right now */
36};
37
38struct ext4_xattr_ibody_header {
39 __le32 h_magic; /* magic number for identification */
40};
41
42struct ext4_xattr_entry {
43 __u8 e_name_len; /* length of name */
44 __u8 e_name_index; /* attribute name index */
45 __le16 e_value_offs; /* offset in disk block of value */
46 __le32 e_value_block; /* disk block attribute is stored on (n/i) */
47 __le32 e_value_size; /* size of attribute value */
48 __le32 e_hash; /* hash value of name and value */
49 char e_name[0]; /* attribute name */
50};
51
52#define EXT4_XATTR_PAD_BITS 2
53#define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
54#define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
55#define EXT4_XATTR_LEN(name_len) \
56 (((name_len) + EXT4_XATTR_ROUND + \
57 sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
58#define EXT4_XATTR_NEXT(entry) \
59 ((struct ext4_xattr_entry *)( \
60 (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)))
61#define EXT4_XATTR_SIZE(size) \
62 (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
63
64#define IHDR(inode, raw_inode) \
65 ((struct ext4_xattr_ibody_header *) \
66 ((void *)raw_inode + \
67 EXT4_GOOD_OLD_INODE_SIZE + \
68 EXT4_I(inode)->i_extra_isize))
69#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
70
71#define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data))
72#define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr))
73#define BFIRST(bh) ENTRY(BHDR(bh)+1)
74#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
75
76#define EXT4_ZERO_XATTR_VALUE ((void *)-1)
77
78struct ext4_xattr_info {
79 int name_index;
80 const char *name;
81 const void *value;
82 size_t value_len;
83};
84
85struct ext4_xattr_search {
86 struct ext4_xattr_entry *first;
87 void *base;
88 void *end;
89 struct ext4_xattr_entry *here;
90 int not_found;
91};
92
93struct ext4_xattr_ibody_find {
94 struct ext4_xattr_search s;
95 struct ext4_iloc iloc;
96};
97
98extern const struct xattr_handler ext4_xattr_user_handler;
99extern const struct xattr_handler ext4_xattr_trusted_handler;
100extern const struct xattr_handler ext4_xattr_security_handler;
101
102#define EXT4_XATTR_NAME_ENCRYPTION_CONTEXT "c"
103
104extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
105
106extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
107extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
108extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
109
110extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
111extern void ext4_xattr_put_super(struct super_block *);
112
113extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
114 struct ext4_inode *raw_inode, handle_t *handle);
115
116extern const struct xattr_handler *ext4_xattr_handlers[];
117
118extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
119 struct ext4_xattr_ibody_find *is);
120extern int ext4_xattr_ibody_get(struct inode *inode, int name_index,
121 const char *name,
122 void *buffer, size_t buffer_size);
123extern int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
124 struct ext4_xattr_info *i,
125 struct ext4_xattr_ibody_find *is);
126
127extern struct mb_cache *ext4_xattr_create_cache(char *name);
128extern void ext4_xattr_destroy_cache(struct mb_cache *);
129
130#ifdef CONFIG_EXT4_FS_SECURITY
131extern int ext4_init_security(handle_t *handle, struct inode *inode,
132 struct inode *dir, const struct qstr *qstr);
133#else
134static inline int ext4_init_security(handle_t *handle, struct inode *inode,
135 struct inode *dir, const struct qstr *qstr)
136{
137 return 0;
138}
139#endif