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 static 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);
63 acl = posix_acl_from_xattr(value, size);
68 set_cached_acl(inode, type, acl);
71 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
72 /* FIXME, who returns -ENOENT? I think nobody */
74 set_cached_acl(inode, type, 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;
88 if (!IS_POSIXACL(dentry->d_inode))
91 acl = btrfs_get_acl(dentry->d_inode, type);
97 ret = posix_acl_to_xattr(acl, value, size);
98 posix_acl_release(acl);
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)
115 ret = posix_acl_valid(acl);
122 case ACL_TYPE_ACCESS:
123 mode = inode->i_mode;
124 name = POSIX_ACL_XATTR_ACCESS;
126 ret = posix_acl_equiv_mode(acl, &mode);
129 inode->i_mode = mode;
133 case ACL_TYPE_DEFAULT:
134 if (!S_ISDIR(inode->i_mode))
135 return acl ? -EINVAL : 0;
136 name = POSIX_ACL_XATTR_DEFAULT;
143 size = posix_acl_xattr_size(acl->a_count);
144 value = kmalloc(size, GFP_NOFS);
150 ret = posix_acl_to_xattr(acl, value, size);
155 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
160 set_cached_acl(inode, type, acl);
165 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
166 const void *value, size_t size, int flags, int type)
169 struct posix_acl *acl = NULL;
171 if (!inode_owner_or_capable(dentry->d_inode))
174 if (!IS_POSIXACL(dentry->d_inode))
178 acl = posix_acl_from_xattr(value, size);
183 ret = posix_acl_valid(acl);
189 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
191 posix_acl_release(acl);
196 int btrfs_check_acl(struct inode *inode, int mask, unsigned int flags)
200 if (flags & IPERM_FLAG_RCU) {
201 if (!negative_cached_acl(inode, ACL_TYPE_ACCESS))
205 struct posix_acl *acl;
206 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
210 error = posix_acl_permission(inode, acl, mask);
211 posix_acl_release(acl);
219 * btrfs_init_acl is already generally called under fs_mutex, so the locking
220 * stuff has been fixed to work with that. If the locking stuff changes, we
221 * need to re-evaluate the acl locking stuff.
223 int btrfs_init_acl(struct btrfs_trans_handle *trans,
224 struct inode *inode, struct inode *dir)
226 struct posix_acl *acl = NULL;
229 /* this happens with subvols */
233 if (!S_ISLNK(inode->i_mode)) {
234 if (IS_POSIXACL(dir)) {
235 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
241 inode->i_mode &= ~current_umask();
244 if (IS_POSIXACL(dir) && acl) {
245 struct posix_acl *clone;
248 if (S_ISDIR(inode->i_mode)) {
249 ret = btrfs_set_acl(trans, inode, acl,
254 clone = posix_acl_clone(acl, GFP_NOFS);
259 mode = inode->i_mode;
260 ret = posix_acl_create_masq(clone, &mode);
262 inode->i_mode = mode;
265 ret = btrfs_set_acl(trans, inode, clone,
269 posix_acl_release(clone);
272 posix_acl_release(acl);
277 int btrfs_acl_chmod(struct inode *inode)
279 struct posix_acl *acl, *clone;
282 if (S_ISLNK(inode->i_mode))
285 if (!IS_POSIXACL(inode))
288 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
289 if (IS_ERR_OR_NULL(acl))
292 clone = posix_acl_clone(acl, GFP_KERNEL);
293 posix_acl_release(acl);
297 ret = posix_acl_chmod_masq(clone, inode->i_mode);
299 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
301 posix_acl_release(clone);
306 const struct xattr_handler btrfs_xattr_acl_default_handler = {
307 .prefix = POSIX_ACL_XATTR_DEFAULT,
308 .flags = ACL_TYPE_DEFAULT,
309 .get = btrfs_xattr_acl_get,
310 .set = btrfs_xattr_acl_set,
313 const struct xattr_handler btrfs_xattr_acl_access_handler = {
314 .prefix = POSIX_ACL_XATTR_ACCESS,
315 .flags = ACL_TYPE_ACCESS,
316 .get = btrfs_xattr_acl_get,
317 .set = btrfs_xattr_acl_set,