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 "rgrp.h"
28 #include "trans.h"
29 #include "util.h"
30
gfs2_acl_name(int type)31 static const char *gfs2_acl_name(int type)
32 {
33 switch (type) {
34 case ACL_TYPE_ACCESS:
35 return XATTR_POSIX_ACL_ACCESS;
36 case ACL_TYPE_DEFAULT:
37 return XATTR_POSIX_ACL_DEFAULT;
38 }
39 return NULL;
40 }
41
__gfs2_get_acl(struct inode * inode,int type)42 static struct posix_acl *__gfs2_get_acl(struct inode *inode, int type)
43 {
44 struct gfs2_inode *ip = GFS2_I(inode);
45 struct posix_acl *acl;
46 const char *name;
47 char *data;
48 int len;
49
50 if (!ip->i_eattr)
51 return NULL;
52
53 name = gfs2_acl_name(type);
54 len = gfs2_xattr_acl_get(ip, name, &data);
55 if (len <= 0)
56 return ERR_PTR(len);
57 acl = posix_acl_from_xattr(&init_user_ns, data, len);
58 kfree(data);
59 return acl;
60 }
61
gfs2_get_acl(struct inode * inode,int type)62 struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
63 {
64 struct gfs2_inode *ip = GFS2_I(inode);
65 struct gfs2_holder gh;
66 bool need_unlock = false;
67 struct posix_acl *acl;
68
69 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
70 int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
71 LM_FLAG_ANY, &gh);
72 if (ret)
73 return ERR_PTR(ret);
74 need_unlock = true;
75 }
76 acl = __gfs2_get_acl(inode, type);
77 if (need_unlock)
78 gfs2_glock_dq_uninit(&gh);
79 return acl;
80 }
81
__gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)82 int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
83 {
84 int error;
85 size_t len;
86 char *data;
87 const char *name = gfs2_acl_name(type);
88
89 if (acl) {
90 len = posix_acl_xattr_size(acl->a_count);
91 data = kmalloc(len, GFP_NOFS);
92 if (data == NULL)
93 return -ENOMEM;
94 error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
95 if (error < 0)
96 goto out;
97 } else {
98 data = NULL;
99 len = 0;
100 }
101
102 error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
103 if (error)
104 goto out;
105 set_cached_acl(inode, type, acl);
106 out:
107 kfree(data);
108 return error;
109 }
110
gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)111 int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
112 {
113 struct gfs2_inode *ip = GFS2_I(inode);
114 struct gfs2_holder gh;
115 bool need_unlock = false;
116 int ret;
117 umode_t mode;
118
119 if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
120 return -E2BIG;
121
122 ret = gfs2_rsqa_alloc(ip);
123 if (ret)
124 return ret;
125
126 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
127 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
128 if (ret)
129 return ret;
130 need_unlock = true;
131 }
132
133 mode = inode->i_mode;
134 if (type == ACL_TYPE_ACCESS && acl) {
135 ret = posix_acl_update_mode(inode, &mode, &acl);
136 if (ret)
137 goto unlock;
138 }
139
140 ret = __gfs2_set_acl(inode, acl, type);
141 if (!ret && mode != inode->i_mode) {
142 inode->i_ctime = current_time(inode);
143 inode->i_mode = mode;
144 mark_inode_dirty(inode);
145 }
146 unlock:
147 if (need_unlock)
148 gfs2_glock_dq_uninit(&gh);
149 return ret;
150 }
151