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>
25 #include <linux/slab.h>
28 #include "btrfs_inode.h"
31 struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
36 struct posix_acl *acl;
38 if (!IS_POSIXACL(inode))
41 acl = get_cached_acl(inode, type);
42 if (acl != ACL_NOT_CACHED)
47 name = POSIX_ACL_XATTR_ACCESS;
49 case ACL_TYPE_DEFAULT:
50 name = POSIX_ACL_XATTR_DEFAULT;
56 size = __btrfs_getxattr(inode, name, "", 0);
58 value = kzalloc(size, GFP_NOFS);
60 return ERR_PTR(-ENOMEM);
61 size = __btrfs_getxattr(inode, name, value, size);
64 acl = posix_acl_from_xattr(value, size);
65 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
66 /* FIXME, who returns -ENOENT? I think nobody */
74 set_cached_acl(inode, type, acl);
79 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
80 void *value, size_t size, int type)
82 struct posix_acl *acl;
85 if (!IS_POSIXACL(dentry->d_inode))
88 acl = btrfs_get_acl(dentry->d_inode, type);
94 ret = posix_acl_to_xattr(acl, value, size);
95 posix_acl_release(acl);
101 * Needs to be called with fs_mutex held
103 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
104 struct inode *inode, struct posix_acl *acl, int type)
111 ret = posix_acl_valid(acl);
118 case ACL_TYPE_ACCESS:
119 name = POSIX_ACL_XATTR_ACCESS;
121 case ACL_TYPE_DEFAULT:
122 if (!S_ISDIR(inode->i_mode))
123 return acl ? -EINVAL : 0;
124 name = POSIX_ACL_XATTR_DEFAULT;
131 size = posix_acl_xattr_size(acl->a_count);
132 value = kmalloc(size, GFP_NOFS);
138 ret = posix_acl_to_xattr(acl, value, size);
143 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
148 set_cached_acl(inode, type, acl);
153 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
154 const void *value, size_t size, int flags, int type)
157 struct posix_acl *acl = NULL;
158 struct inode *inode = dentry->d_inode;
159 umode_t old_mode = inode->i_mode;
161 if (!inode_owner_or_capable(inode))
164 if (!IS_POSIXACL(inode))
168 acl = posix_acl_from_xattr(value, size);
173 ret = posix_acl_valid(acl);
179 if (type == ACL_TYPE_ACCESS && acl) {
180 ret = posix_acl_update_mode(inode, &inode->i_mode, &acl);
184 ret = btrfs_set_acl(NULL, inode, acl, type);
186 inode->i_mode = old_mode;
188 posix_acl_release(acl);
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;
204 /* this happens with subvols */
208 if (!S_ISLNK(inode->i_mode)) {
209 if (IS_POSIXACL(dir)) {
210 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
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,
226 ret = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
232 ret = btrfs_set_acl(trans, inode, acl, ACL_TYPE_ACCESS);
236 posix_acl_release(acl);
241 int btrfs_acl_chmod(struct inode *inode)
243 struct posix_acl *acl;
246 if (S_ISLNK(inode->i_mode))
249 if (!IS_POSIXACL(inode))
252 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
253 if (IS_ERR_OR_NULL(acl))
256 ret = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
259 ret = btrfs_set_acl(NULL, inode, acl, ACL_TYPE_ACCESS);
260 posix_acl_release(acl);
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,