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_FS_POSIX_ACL
32 static void btrfs_update_cached_acl(struct inode
*inode
,
33 struct posix_acl
**p_acl
,
34 struct posix_acl
*acl
)
36 spin_lock(&inode
->i_lock
);
37 if (*p_acl
&& *p_acl
!= BTRFS_ACL_NOT_CACHED
)
38 posix_acl_release(*p_acl
);
39 *p_acl
= posix_acl_dup(acl
);
40 spin_unlock(&inode
->i_lock
);
43 static struct posix_acl
*btrfs_get_acl(struct inode
*inode
, int type
)
48 struct posix_acl
*acl
= NULL
, **p_acl
;
52 name
= POSIX_ACL_XATTR_ACCESS
;
53 p_acl
= &BTRFS_I(inode
)->i_acl
;
55 case ACL_TYPE_DEFAULT
:
56 name
= POSIX_ACL_XATTR_DEFAULT
;
57 p_acl
= &BTRFS_I(inode
)->i_default_acl
;
60 return ERR_PTR(-EINVAL
);
63 spin_lock(&inode
->i_lock
);
64 if (*p_acl
!= BTRFS_ACL_NOT_CACHED
)
65 acl
= posix_acl_dup(*p_acl
);
66 spin_unlock(&inode
->i_lock
);
72 size
= __btrfs_getxattr(inode
, name
, "", 0);
74 value
= kzalloc(size
, GFP_NOFS
);
76 return ERR_PTR(-ENOMEM
);
77 size
= __btrfs_getxattr(inode
, name
, value
, size
);
79 acl
= posix_acl_from_xattr(value
, size
);
80 btrfs_update_cached_acl(inode
, p_acl
, acl
);
83 } else if (size
== -ENOENT
) {
85 btrfs_update_cached_acl(inode
, p_acl
, acl
);
91 static int btrfs_xattr_get_acl(struct inode
*inode
, int type
,
92 void *value
, size_t size
)
94 struct posix_acl
*acl
;
97 acl
= btrfs_get_acl(inode
, type
);
103 ret
= posix_acl_to_xattr(acl
, value
, size
);
104 posix_acl_release(acl
);
110 * Needs to be called with fs_mutex held
112 static int btrfs_set_acl(struct inode
*inode
, struct posix_acl
*acl
, int type
)
116 struct posix_acl
**p_acl
;
121 ret
= posix_acl_valid(acl
);
128 case ACL_TYPE_ACCESS
:
129 mode
= inode
->i_mode
;
130 ret
= posix_acl_equiv_mode(acl
, &mode
);
134 inode
->i_mode
= mode
;
135 name
= POSIX_ACL_XATTR_ACCESS
;
136 p_acl
= &BTRFS_I(inode
)->i_acl
;
138 case ACL_TYPE_DEFAULT
:
139 if (!S_ISDIR(inode
->i_mode
))
140 return acl
? -EINVAL
: 0;
141 name
= POSIX_ACL_XATTR_DEFAULT
;
142 p_acl
= &BTRFS_I(inode
)->i_default_acl
;
149 size
= posix_acl_xattr_size(acl
->a_count
);
150 value
= kmalloc(size
, GFP_NOFS
);
156 ret
= posix_acl_to_xattr(acl
, value
, size
);
161 ret
= __btrfs_setxattr(inode
, name
, value
, size
, 0);
168 btrfs_update_cached_acl(inode
, p_acl
, acl
);
173 static int btrfs_xattr_set_acl(struct inode
*inode
, int type
,
174 const void *value
, size_t size
)
177 struct posix_acl
*acl
= NULL
;
180 acl
= posix_acl_from_xattr(value
, size
);
184 } else if (IS_ERR(acl
)) {
189 ret
= btrfs_set_acl(inode
, acl
, type
);
191 posix_acl_release(acl
);
197 static int btrfs_xattr_acl_access_get(struct inode
*inode
, const char *name
,
198 void *value
, size_t size
)
200 return btrfs_xattr_get_acl(inode
, ACL_TYPE_ACCESS
, value
, size
);
203 static int btrfs_xattr_acl_access_set(struct inode
*inode
, const char *name
,
204 const void *value
, size_t size
, int flags
)
206 return btrfs_xattr_set_acl(inode
, ACL_TYPE_ACCESS
, value
, size
);
209 static int btrfs_xattr_acl_default_get(struct inode
*inode
, const char *name
,
210 void *value
, size_t size
)
212 return btrfs_xattr_get_acl(inode
, ACL_TYPE_DEFAULT
, value
, size
);
215 static int btrfs_xattr_acl_default_set(struct inode
*inode
, const char *name
,
216 const void *value
, size_t size
, int flags
)
218 return btrfs_xattr_set_acl(inode
, ACL_TYPE_DEFAULT
, value
, size
);
221 int btrfs_check_acl(struct inode
*inode
, int mask
)
223 struct posix_acl
*acl
;
226 acl
= btrfs_get_acl(inode
, ACL_TYPE_ACCESS
);
231 error
= posix_acl_permission(inode
, acl
, mask
);
232 posix_acl_release(acl
);
239 * btrfs_init_acl is already generally called under fs_mutex, so the locking
240 * stuff has been fixed to work with that. If the locking stuff changes, we
241 * need to re-evaluate the acl locking stuff.
243 int btrfs_init_acl(struct inode
*inode
, struct inode
*dir
)
245 struct posix_acl
*acl
= NULL
;
248 /* this happens with subvols */
252 if (!S_ISLNK(inode
->i_mode
)) {
253 if (IS_POSIXACL(dir
)) {
254 acl
= btrfs_get_acl(dir
, ACL_TYPE_DEFAULT
);
260 inode
->i_mode
&= ~current
->fs
->umask
;
263 if (IS_POSIXACL(dir
) && acl
) {
264 struct posix_acl
*clone
;
267 if (S_ISDIR(inode
->i_mode
)) {
268 ret
= btrfs_set_acl(inode
, acl
, ACL_TYPE_DEFAULT
);
272 clone
= posix_acl_clone(acl
, GFP_NOFS
);
277 mode
= inode
->i_mode
;
278 ret
= posix_acl_create_masq(clone
, &mode
);
280 inode
->i_mode
= mode
;
283 ret
= btrfs_set_acl(inode
, clone
,
289 posix_acl_release(acl
);
294 int btrfs_acl_chmod(struct inode
*inode
)
296 struct posix_acl
*acl
, *clone
;
299 if (S_ISLNK(inode
->i_mode
))
302 if (!IS_POSIXACL(inode
))
305 acl
= btrfs_get_acl(inode
, ACL_TYPE_ACCESS
);
306 if (IS_ERR(acl
) || !acl
)
309 clone
= posix_acl_clone(acl
, GFP_KERNEL
);
310 posix_acl_release(acl
);
314 ret
= posix_acl_chmod_masq(clone
, inode
->i_mode
);
316 ret
= btrfs_set_acl(inode
, clone
, ACL_TYPE_ACCESS
);
318 posix_acl_release(clone
);
323 struct xattr_handler btrfs_xattr_acl_default_handler
= {
324 .prefix
= POSIX_ACL_XATTR_DEFAULT
,
325 .get
= btrfs_xattr_acl_default_get
,
326 .set
= btrfs_xattr_acl_default_set
,
329 struct xattr_handler btrfs_xattr_acl_access_handler
= {
330 .prefix
= POSIX_ACL_XATTR_ACCESS
,
331 .get
= btrfs_xattr_acl_access_get
,
332 .set
= btrfs_xattr_acl_access_set
,
335 #else /* CONFIG_FS_POSIX_ACL */
337 int btrfs_acl_chmod(struct inode
*inode
)
342 int btrfs_init_acl(struct inode
*inode
, struct inode
*dir
)
347 int btrfs_check_acl(struct inode
*inode
, int mask
)
352 #endif /* CONFIG_FS_POSIX_ACL */