usb: gadget: renesas_usbhs: fix compile warning
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / btrfs / acl.c
blobeb159aaa5a1139204e2d24333bc32eae8433261d
1 /*
2 * Copyright (C) 2007 Red Hat. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/fs.h>
20 #include <linux/string.h>
21 #include <linux/xattr.h>
22 #include <linux/posix_acl_xattr.h>
23 #include <linux/posix_acl.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
27 #include "ctree.h"
28 #include "btrfs_inode.h"
29 #include "xattr.h"
31 struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
33 int size;
34 const char *name;
35 char *value = NULL;
36 struct posix_acl *acl;
38 if (!IS_POSIXACL(inode))
39 return NULL;
41 acl = get_cached_acl(inode, type);
42 if (acl != ACL_NOT_CACHED)
43 return acl;
45 switch (type) {
46 case ACL_TYPE_ACCESS:
47 name = POSIX_ACL_XATTR_ACCESS;
48 break;
49 case ACL_TYPE_DEFAULT:
50 name = POSIX_ACL_XATTR_DEFAULT;
51 break;
52 default:
53 BUG();
56 size = __btrfs_getxattr(inode, name, "", 0);
57 if (size > 0) {
58 value = kzalloc(size, GFP_NOFS);
59 if (!value)
60 return ERR_PTR(-ENOMEM);
61 size = __btrfs_getxattr(inode, name, value, size);
62 if (size > 0) {
63 acl = posix_acl_from_xattr(value, size);
64 if (IS_ERR(acl)) {
65 kfree(value);
66 return acl;
68 set_cached_acl(inode, type, acl);
70 kfree(value);
71 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
72 /* FIXME, who returns -ENOENT? I think nobody */
73 acl = NULL;
74 set_cached_acl(inode, type, acl);
75 } else {
76 acl = ERR_PTR(-EIO);
79 return acl;
82 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
83 void *value, size_t size, int type)
85 struct posix_acl *acl;
86 int ret = 0;
88 if (!IS_POSIXACL(dentry->d_inode))
89 return -EOPNOTSUPP;
91 acl = btrfs_get_acl(dentry->d_inode, type);
93 if (IS_ERR(acl))
94 return PTR_ERR(acl);
95 if (acl == NULL)
96 return -ENODATA;
97 ret = posix_acl_to_xattr(acl, value, size);
98 posix_acl_release(acl);
100 return ret;
104 * Needs to be called with fs_mutex held
106 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
107 struct inode *inode, struct posix_acl *acl, int type)
109 int ret, size = 0;
110 const char *name;
111 char *value = NULL;
113 if (acl) {
114 ret = posix_acl_valid(acl);
115 if (ret < 0)
116 return ret;
117 ret = 0;
120 switch (type) {
121 case ACL_TYPE_ACCESS:
122 name = POSIX_ACL_XATTR_ACCESS;
123 if (acl) {
124 ret = posix_acl_equiv_mode(acl, &inode->i_mode);
125 if (ret < 0)
126 return ret;
128 ret = 0;
129 break;
130 case ACL_TYPE_DEFAULT:
131 if (!S_ISDIR(inode->i_mode))
132 return acl ? -EINVAL : 0;
133 name = POSIX_ACL_XATTR_DEFAULT;
134 break;
135 default:
136 return -EINVAL;
139 if (acl) {
140 size = posix_acl_xattr_size(acl->a_count);
141 value = kmalloc(size, GFP_NOFS);
142 if (!value) {
143 ret = -ENOMEM;
144 goto out;
147 ret = posix_acl_to_xattr(acl, value, size);
148 if (ret < 0)
149 goto out;
152 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
153 out:
154 kfree(value);
156 if (!ret)
157 set_cached_acl(inode, type, acl);
159 return ret;
162 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
163 const void *value, size_t size, int flags, int type)
165 int ret;
166 struct posix_acl *acl = NULL;
168 if (!inode_owner_or_capable(dentry->d_inode))
169 return -EPERM;
171 if (!IS_POSIXACL(dentry->d_inode))
172 return -EOPNOTSUPP;
174 if (value) {
175 acl = posix_acl_from_xattr(value, size);
176 if (IS_ERR(acl))
177 return PTR_ERR(acl);
179 if (acl) {
180 ret = posix_acl_valid(acl);
181 if (ret)
182 goto out;
186 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
187 out:
188 posix_acl_release(acl);
190 return ret;
194 * btrfs_init_acl is already generally called under fs_mutex, so the locking
195 * stuff has been fixed to work with that. If the locking stuff changes, we
196 * need to re-evaluate the acl locking stuff.
198 int btrfs_init_acl(struct btrfs_trans_handle *trans,
199 struct inode *inode, struct inode *dir)
201 struct posix_acl *acl = NULL;
202 int ret = 0;
204 /* this happens with subvols */
205 if (!dir)
206 return 0;
208 if (!S_ISLNK(inode->i_mode)) {
209 if (IS_POSIXACL(dir)) {
210 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
211 if (IS_ERR(acl))
212 return PTR_ERR(acl);
215 if (!acl)
216 inode->i_mode &= ~current_umask();
219 if (IS_POSIXACL(dir) && acl) {
220 if (S_ISDIR(inode->i_mode)) {
221 ret = btrfs_set_acl(trans, inode, acl,
222 ACL_TYPE_DEFAULT);
223 if (ret)
224 goto failed;
226 ret = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
227 if (ret < 0)
228 return ret;
230 if (ret > 0) {
231 /* we need an acl */
232 ret = btrfs_set_acl(trans, inode, acl, ACL_TYPE_ACCESS);
235 failed:
236 posix_acl_release(acl);
238 return ret;
241 int btrfs_acl_chmod(struct inode *inode)
243 struct posix_acl *acl;
244 int ret = 0;
246 if (S_ISLNK(inode->i_mode))
247 return -EOPNOTSUPP;
249 if (!IS_POSIXACL(inode))
250 return 0;
252 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
253 if (IS_ERR_OR_NULL(acl))
254 return PTR_ERR(acl);
256 ret = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
257 if (ret)
258 return ret;
259 ret = btrfs_set_acl(NULL, inode, acl, ACL_TYPE_ACCESS);
260 posix_acl_release(acl);
261 return ret;
264 const struct xattr_handler btrfs_xattr_acl_default_handler = {
265 .prefix = POSIX_ACL_XATTR_DEFAULT,
266 .flags = ACL_TYPE_DEFAULT,
267 .get = btrfs_xattr_acl_get,
268 .set = btrfs_xattr_acl_set,
271 const struct xattr_handler btrfs_xattr_acl_access_handler = {
272 .prefix = POSIX_ACL_XATTR_ACCESS,
273 .flags = ACL_TYPE_ACCESS,
274 .get = btrfs_xattr_acl_get,
275 .set = btrfs_xattr_acl_set,