1/*
2  File: linux/xattr.h
3
4  Extended attributes handling.
5
6  Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org>
7  Copyright (c) 2001-2002 Silicon Graphics, Inc.  All Rights Reserved.
8  Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
9*/
10#ifndef _LINUX_XATTR_H
11#define _LINUX_XATTR_H
12
13
14#include <linux/slab.h>
15#include <linux/types.h>
16#include <linux/spinlock.h>
17#include <uapi/linux/xattr.h>
18
19struct inode;
20struct dentry;
21
22struct xattr_handler {
23	const char *prefix;
24	int flags;	/* fs private flags passed back to the handlers */
25	size_t (*list)(struct dentry *dentry, char *list, size_t list_size,
26		       const char *name, size_t name_len, int handler_flags);
27	int (*get)(struct dentry *dentry, const char *name, void *buffer,
28		   size_t size, int handler_flags);
29	int (*set)(struct dentry *dentry, const char *name, const void *buffer,
30		   size_t size, int flags, int handler_flags);
31};
32
33struct xattr {
34	const char *name;
35	void *value;
36	size_t value_len;
37};
38
39ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
40ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
41ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
42int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
43int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
44int vfs_removexattr(struct dentry *, const char *);
45
46ssize_t generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t size);
47ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
48int generic_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags);
49int generic_removexattr(struct dentry *dentry, const char *name);
50ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
51			   char **xattr_value, size_t size, gfp_t flags);
52int vfs_xattr_cmp(struct dentry *dentry, const char *xattr_name,
53		  const char *value, size_t size, gfp_t flags);
54
55struct simple_xattrs {
56	struct list_head head;
57	spinlock_t lock;
58};
59
60struct simple_xattr {
61	struct list_head list;
62	char *name;
63	size_t size;
64	char value[0];
65};
66
67/*
68 * initialize the simple_xattrs structure
69 */
70static inline void simple_xattrs_init(struct simple_xattrs *xattrs)
71{
72	INIT_LIST_HEAD(&xattrs->head);
73	spin_lock_init(&xattrs->lock);
74}
75
76/*
77 * free all the xattrs
78 */
79static inline void simple_xattrs_free(struct simple_xattrs *xattrs)
80{
81	struct simple_xattr *xattr, *node;
82
83	list_for_each_entry_safe(xattr, node, &xattrs->head, list) {
84		kfree(xattr->name);
85		kfree(xattr);
86	}
87}
88
89struct simple_xattr *simple_xattr_alloc(const void *value, size_t size);
90int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
91		     void *buffer, size_t size);
92int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
93		     const void *value, size_t size, int flags);
94int simple_xattr_remove(struct simple_xattrs *xattrs, const char *name);
95ssize_t simple_xattr_list(struct simple_xattrs *xattrs, char *buffer,
96			  size_t size);
97void simple_xattr_list_add(struct simple_xattrs *xattrs,
98			   struct simple_xattr *new_xattr);
99
100#endif	/* _LINUX_XATTR_H */
101