summaryrefslogtreecommitdiffstats
path: root/include/linux/xattr.h
blob: d23ce8e9af6f5fedf5845e8fc4fb5886bf222c5c (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
/*
  File: linux/xattr.h

  Extended attributes handling.

  Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org>
  Copyright (c) 2001-2002 Silicon Graphics, Inc.  All Rights Reserved.
  Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
*/
#ifndef _LINUX_XATTR_H
#define _LINUX_XATTR_H


#include <linux/slab.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <uapi/linux/xattr.h>

struct inode;
struct dentry;

/*
 * struct xattr_handler: When @name is set, match attributes with exactly that
 * name.  When @prefix is set instead, match attributes with that prefix and
 * with a non-empty suffix.
 */
struct xattr_handler {
	const char *name;
	const char *prefix;
	int flags;      /* fs private flags */
	size_t (*list)(const struct xattr_handler *, struct dentry *dentry,
		       char *list, size_t list_size, const char *name,
		       size_t name_len);
	int (*get)(const struct xattr_handler *, struct dentry *dentry,
		   const char *name, void *buffer, size_t size);
	int (*set)(const struct xattr_handler *, struct dentry *dentry,
		   const char *name, const void *buffer, size_t size,
		   int flags);
};

const char *xattr_full_name(const struct xattr_handler *, const char *);

struct xattr {
	const char *name;
	void *value;
	size_t value_len;
};

ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
int vfs_removexattr(struct dentry *, const char *);

ssize_t generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t size);
ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
int generic_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags);
int generic_removexattr(struct dentry *dentry, const char *name);
ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
			   char **xattr_value, size_t size, gfp_t flags);

static inline const char *xattr_prefix(const struct xattr_handler *handler)
{
	return handler->prefix ?: handler->name;
}

struct simple_xattrs {
	struct list_head head;
	spinlock_t lock;
};

struct simple_xattr {
	struct list_head list;
	char *name;
	size_t size;
	char value[0];
};

/*
 * initialize the simple_xattrs structure
 */
static inline void simple_xattrs_init(struct simple_xattrs *xattrs)
{
	INIT_LIST_HEAD(&xattrs->head);
	spin_lock_init(&xattrs->lock);
}

/*
 * free all the xattrs
 */
static inline void simple_xattrs_free(struct simple_xattrs *xattrs)
{
	struct simple_xattr *xattr, *node;

	list_for_each_entry_safe(xattr, node, &xattrs->head, list) {
		kfree(xattr->name);
		kfree(xattr);
	}
}

struct simple_xattr *simple_xattr_alloc(const void *value, size_t size);
int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
		     void *buffer, size_t size);
int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
		     const void *value, size_t size, int flags);
ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer,
			  size_t size);
void simple_xattr_list_add(struct simple_xattrs *xattrs,
			   struct simple_xattr *new_xattr);

#endif	/* _LINUX_XATTR_H */