1/*
2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13#include <linux/completion.h>
14#include <linux/buffer_head.h>
15#include <linux/xattr.h>
16#include <linux/posix_acl.h>
17#include <linux/posix_acl_xattr.h>
18#include <linux/gfs2_ondisk.h>
19
20#include "gfs2.h"
21#include "incore.h"
22#include "acl.h"
23#include "xattr.h"
24#include "glock.h"
25#include "inode.h"
26#include "meta_io.h"
27#include "trans.h"
28#include "util.h"
29
30static const char *gfs2_acl_name(int type)
31{
32	switch (type) {
33	case ACL_TYPE_ACCESS:
34		return GFS2_POSIX_ACL_ACCESS;
35	case ACL_TYPE_DEFAULT:
36		return GFS2_POSIX_ACL_DEFAULT;
37	}
38	return NULL;
39}
40
41struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
42{
43	struct gfs2_inode *ip = GFS2_I(inode);
44	struct posix_acl *acl;
45	const char *name;
46	char *data;
47	int len;
48
49	if (!ip->i_eattr)
50		return NULL;
51
52	name = gfs2_acl_name(type);
53	if (name == NULL)
54		return ERR_PTR(-EINVAL);
55
56	len = gfs2_xattr_acl_get(ip, name, &data);
57	if (len < 0)
58		return ERR_PTR(len);
59	if (len == 0)
60		return NULL;
61
62	acl = posix_acl_from_xattr(&init_user_ns, data, len);
63	kfree(data);
64	return acl;
65}
66
67int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
68{
69	int error;
70	int len;
71	char *data;
72	const char *name = gfs2_acl_name(type);
73
74	BUG_ON(name == NULL);
75
76	if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
77		return -E2BIG;
78
79	if (type == ACL_TYPE_ACCESS) {
80		umode_t mode = inode->i_mode;
81
82		error = posix_acl_equiv_mode(acl, &mode);
83		if (error < 0)
84			return error;
85
86		if (error == 0)
87			acl = NULL;
88
89		if (mode != inode->i_mode) {
90			inode->i_mode = mode;
91			mark_inode_dirty(inode);
92		}
93	}
94
95	if (acl) {
96		len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
97		if (len == 0)
98			return 0;
99		data = kmalloc(len, GFP_NOFS);
100		if (data == NULL)
101			return -ENOMEM;
102		error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
103		if (error < 0)
104			goto out;
105	} else {
106		data = NULL;
107		len = 0;
108	}
109
110	error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
111	if (error)
112		goto out;
113	set_cached_acl(inode, type, acl);
114out:
115	kfree(data);
116	return error;
117}
118