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.
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>
27 #include "btrfs_inode.h"
30 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
32 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
37 struct posix_acl *acl;
39 acl = get_cached_acl(inode, type);
40 if (acl != ACL_NOT_CACHED)
45 name = POSIX_ACL_XATTR_ACCESS;
47 case ACL_TYPE_DEFAULT:
48 name = POSIX_ACL_XATTR_DEFAULT;
54 size = __btrfs_getxattr(inode, name, "", 0);
56 value = kzalloc(size, GFP_NOFS);
58 return ERR_PTR(-ENOMEM);
59 size = __btrfs_getxattr(inode, name, value, size);
61 acl = posix_acl_from_xattr(value, size);
62 set_cached_acl(inode, type, acl);
65 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
66 /* FIXME, who returns -ENOENT? I think nobody */
68 set_cached_acl(inode, type, acl);
76 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
77 void *value, size_t size, int type)
79 struct posix_acl *acl;
82 acl = btrfs_get_acl(dentry->d_inode, type);
88 ret = posix_acl_to_xattr(acl, value, size);
89 posix_acl_release(acl);
95 * Needs to be called with fs_mutex held
97 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
98 struct inode *inode, struct posix_acl *acl, int type)
106 ret = posix_acl_valid(acl);
113 case ACL_TYPE_ACCESS:
114 mode = inode->i_mode;
115 ret = posix_acl_equiv_mode(acl, &mode);
119 inode->i_mode = mode;
120 name = POSIX_ACL_XATTR_ACCESS;
122 case ACL_TYPE_DEFAULT:
123 if (!S_ISDIR(inode->i_mode))
124 return acl ? -EINVAL : 0;
125 name = POSIX_ACL_XATTR_DEFAULT;
132 size = posix_acl_xattr_size(acl->a_count);
133 value = kmalloc(size, GFP_NOFS);
139 ret = posix_acl_to_xattr(acl, value, size);
144 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
149 set_cached_acl(inode, type, acl);
154 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
155 const void *value, size_t size, int flags, int type)
158 struct posix_acl *acl = NULL;
161 acl = posix_acl_from_xattr(value, size);
165 } else if (IS_ERR(acl)) {
170 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
172 posix_acl_release(acl);
177 int btrfs_check_acl(struct inode *inode, int mask)
179 struct posix_acl *acl;
182 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
187 error = posix_acl_permission(inode, acl, mask);
188 posix_acl_release(acl);
195 * btrfs_init_acl is already generally called under fs_mutex, so the locking
196 * stuff has been fixed to work with that. If the locking stuff changes, we
197 * need to re-evaluate the acl locking stuff.
199 int btrfs_init_acl(struct btrfs_trans_handle *trans,
200 struct inode *inode, struct inode *dir)
202 struct posix_acl *acl = NULL;
205 /* this happens with subvols */
209 if (!S_ISLNK(inode->i_mode)) {
210 if (IS_POSIXACL(dir)) {
211 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
217 inode->i_mode &= ~current_umask();
220 if (IS_POSIXACL(dir) && acl) {
221 struct posix_acl *clone;
224 if (S_ISDIR(inode->i_mode)) {
225 ret = btrfs_set_acl(trans, inode, acl,
230 clone = posix_acl_clone(acl, GFP_NOFS);
235 mode = inode->i_mode;
236 ret = posix_acl_create_masq(clone, &mode);
238 inode->i_mode = mode;
241 ret = btrfs_set_acl(trans, inode, clone,
247 posix_acl_release(acl);
252 int btrfs_acl_chmod(struct inode *inode)
254 struct posix_acl *acl, *clone;
257 if (S_ISLNK(inode->i_mode))
260 if (!IS_POSIXACL(inode))
263 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
264 if (IS_ERR(acl) || !acl)
267 clone = posix_acl_clone(acl, GFP_KERNEL);
268 posix_acl_release(acl);
272 ret = posix_acl_chmod_masq(clone, inode->i_mode);
274 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
276 posix_acl_release(clone);
281 struct xattr_handler btrfs_xattr_acl_default_handler = {
282 .prefix = POSIX_ACL_XATTR_DEFAULT,
283 .flags = ACL_TYPE_DEFAULT,
284 .get = btrfs_xattr_acl_get,
285 .set = btrfs_xattr_acl_set,
288 struct xattr_handler btrfs_xattr_acl_access_handler = {
289 .prefix = POSIX_ACL_XATTR_ACCESS,
290 .flags = ACL_TYPE_ACCESS,
291 .get = btrfs_xattr_acl_get,
292 .set = btrfs_xattr_acl_set,
295 #else /* CONFIG_BTRFS_FS_POSIX_ACL */
297 int btrfs_acl_chmod(struct inode *inode)
302 int btrfs_init_acl(struct btrfs_trans_handle *trans,
303 struct inode *inode, struct inode *dir)
308 #endif /* CONFIG_BTRFS_FS_POSIX_ACL */