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_get_acl(struct inode *inode, int type,
77 void *value, size_t size)
79 struct posix_acl *acl;
82 acl = btrfs_get_acl(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 name = POSIX_ACL_XATTR_ACCESS;
117 ret = posix_acl_equiv_mode(acl, &mode);
120 inode->i_mode = mode;
124 case ACL_TYPE_DEFAULT:
125 if (!S_ISDIR(inode->i_mode))
126 return acl ? -EINVAL : 0;
127 name = POSIX_ACL_XATTR_DEFAULT;
134 size = posix_acl_xattr_size(acl->a_count);
135 value = kmalloc(size, GFP_NOFS);
141 ret = posix_acl_to_xattr(acl, value, size);
146 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
151 set_cached_acl(inode, type, acl);
156 static int btrfs_xattr_set_acl(struct inode *inode, int type,
157 const void *value, size_t size)
160 struct posix_acl *acl = NULL;
163 acl = posix_acl_from_xattr(value, size);
167 } else if (IS_ERR(acl)) {
172 ret = btrfs_set_acl(NULL, inode, acl, type);
174 posix_acl_release(acl);
180 static int btrfs_xattr_acl_access_get(struct inode *inode, const char *name,
181 void *value, size_t size)
183 return btrfs_xattr_get_acl(inode, ACL_TYPE_ACCESS, value, size);
186 static int btrfs_xattr_acl_access_set(struct inode *inode, const char *name,
187 const void *value, size_t size, int flags)
189 return btrfs_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
192 static int btrfs_xattr_acl_default_get(struct inode *inode, const char *name,
193 void *value, size_t size)
195 return btrfs_xattr_get_acl(inode, ACL_TYPE_DEFAULT, value, size);
198 static int btrfs_xattr_acl_default_set(struct inode *inode, const char *name,
199 const void *value, size_t size, int flags)
201 return btrfs_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
204 int btrfs_check_acl(struct inode *inode, int mask)
206 struct posix_acl *acl;
209 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
214 error = posix_acl_permission(inode, acl, mask);
215 posix_acl_release(acl);
222 * btrfs_init_acl is already generally called under fs_mutex, so the locking
223 * stuff has been fixed to work with that. If the locking stuff changes, we
224 * need to re-evaluate the acl locking stuff.
226 int btrfs_init_acl(struct btrfs_trans_handle *trans,
227 struct inode *inode, struct inode *dir)
229 struct posix_acl *acl = NULL;
232 /* this happens with subvols */
236 if (!S_ISLNK(inode->i_mode)) {
237 if (IS_POSIXACL(dir)) {
238 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
244 inode->i_mode &= ~current_umask();
247 if (IS_POSIXACL(dir) && acl) {
248 struct posix_acl *clone;
251 if (S_ISDIR(inode->i_mode)) {
252 ret = btrfs_set_acl(trans, inode, acl,
257 clone = posix_acl_clone(acl, GFP_NOFS);
262 mode = inode->i_mode;
263 ret = posix_acl_create_masq(clone, &mode);
265 inode->i_mode = mode;
268 ret = btrfs_set_acl(trans, inode, clone,
272 posix_acl_release(clone);
275 posix_acl_release(acl);
280 int btrfs_acl_chmod(struct inode *inode)
282 struct posix_acl *acl, *clone;
285 if (S_ISLNK(inode->i_mode))
288 if (!IS_POSIXACL(inode))
291 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
292 if (IS_ERR(acl) || !acl)
295 clone = posix_acl_clone(acl, GFP_KERNEL);
296 posix_acl_release(acl);
300 ret = posix_acl_chmod_masq(clone, inode->i_mode);
302 ret = btrfs_set_acl(NULL, inode, clone, ACL_TYPE_ACCESS);
304 posix_acl_release(clone);
309 struct xattr_handler btrfs_xattr_acl_default_handler = {
310 .prefix = POSIX_ACL_XATTR_DEFAULT,
311 .get = btrfs_xattr_acl_default_get,
312 .set = btrfs_xattr_acl_default_set,
315 struct xattr_handler btrfs_xattr_acl_access_handler = {
316 .prefix = POSIX_ACL_XATTR_ACCESS,
317 .get = btrfs_xattr_acl_access_get,
318 .set = btrfs_xattr_acl_access_set,
321 #else /* CONFIG_BTRFS_FS_POSIX_ACL */
323 int btrfs_acl_chmod(struct inode *inode)
328 int btrfs_init_acl(struct btrfs_trans_handle *trans,
329 struct inode *inode, struct inode *dir)
334 #endif /* CONFIG_BTRFS_FS_POSIX_ACL */