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 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
33 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
38 struct posix_acl *acl;
40 if (!IS_POSIXACL(inode))
43 acl = get_cached_acl(inode, type);
44 if (acl != ACL_NOT_CACHED)
49 name = POSIX_ACL_XATTR_ACCESS;
51 case ACL_TYPE_DEFAULT:
52 name = POSIX_ACL_XATTR_DEFAULT;
58 size = __btrfs_getxattr(inode, name, "", 0);
60 value = kzalloc(size, GFP_NOFS);
62 return ERR_PTR(-ENOMEM);
63 size = __btrfs_getxattr(inode, name, value, size);
65 acl = posix_acl_from_xattr(value, size);
70 set_cached_acl(inode, type, acl);
73 } else if (size == -ENOENT || size == -ENODATA || size == 0) {
74 /* FIXME, who returns -ENOENT? I think nobody */
76 set_cached_acl(inode, type, acl);
84 static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
85 void *value, size_t size, int type)
87 struct posix_acl *acl;
90 if (!IS_POSIXACL(dentry->d_inode))
93 acl = btrfs_get_acl(dentry->d_inode, type);
99 ret = posix_acl_to_xattr(acl, value, size);
100 posix_acl_release(acl);
106 * Needs to be called with fs_mutex held
108 static int btrfs_set_acl(struct btrfs_trans_handle *trans,
109 struct inode *inode, struct posix_acl *acl, int type)
117 ret = posix_acl_valid(acl);
124 case ACL_TYPE_ACCESS:
125 mode = inode->i_mode;
126 name = POSIX_ACL_XATTR_ACCESS;
128 ret = posix_acl_equiv_mode(acl, &mode);
131 inode->i_mode = mode;
135 case ACL_TYPE_DEFAULT:
136 if (!S_ISDIR(inode->i_mode))
137 return acl ? -EINVAL : 0;
138 name = POSIX_ACL_XATTR_DEFAULT;
145 size = posix_acl_xattr_size(acl->a_count);
146 value = kmalloc(size, GFP_NOFS);
152 ret = posix_acl_to_xattr(acl, value, size);
157 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
162 set_cached_acl(inode, type, acl);
167 static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name,
168 const void *value, size_t size, int flags, int type)
171 struct posix_acl *acl = NULL;
173 if (!inode_owner_or_capable(dentry->d_inode))
176 if (!IS_POSIXACL(dentry->d_inode))
180 acl = posix_acl_from_xattr(value, size);
185 ret = posix_acl_valid(acl);
191 ret = btrfs_set_acl(NULL, dentry->d_inode, acl, type);
193 posix_acl_release(acl);
198 int btrfs_check_acl(struct inode *inode, int mask)
201 struct posix_acl *acl;
203 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
207 error = posix_acl_permission(inode, acl, mask);
208 posix_acl_release(acl);
215 * btrfs_init_acl is already generally called under fs_mutex, so the locking
216 * stuff has been fixed to work with that. If the locking stuff changes, we
217 * need to re-evaluate the acl locking stuff.
219 int btrfs_init_acl(struct btrfs_trans_handle *trans,
220 struct inode *inode, struct inode *dir)
222 struct posix_acl *acl = NULL;
225 /* this happens with subvols */
229 if (!S_ISLNK(inode->i_mode)) {
230 if (IS_POSIXACL(dir)) {
231 acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);
237 inode->i_mode &= ~current_umask();
240 if (IS_POSIXACL(dir) && acl) {
241 struct posix_acl *clone;
244 if (S_ISDIR(inode->i_mode)) {
245 ret = btrfs_set_acl(trans, inode, acl,
250 clone = posix_acl_clone(acl, GFP_NOFS);
255 mode = inode->i_mode;
256 ret = posix_acl_create_masq(clone, &mode);
258 inode->i_mode = mode;
261 ret = btrfs_set_acl(trans, inode, clone,
265 posix_acl_release(clone);
268 posix_acl_release(acl);
273 int btrfs_acl_chmod(struct inode *inode)
275 struct posix_acl *acl;
278 if (S_ISLNK(inode->i_mode))
281 if (!IS_POSIXACL(inode))
284 acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);
285 if (IS_ERR_OR_NULL(acl))
288 ret = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
291 ret = btrfs_set_acl(NULL, inode, acl, ACL_TYPE_ACCESS);
292 posix_acl_release(acl);
296 const struct xattr_handler btrfs_xattr_acl_default_handler = {
297 .prefix = POSIX_ACL_XATTR_DEFAULT,
298 .flags = ACL_TYPE_DEFAULT,
299 .get = btrfs_xattr_acl_get,
300 .set = btrfs_xattr_acl_set,
303 const struct xattr_handler btrfs_xattr_acl_access_handler = {
304 .prefix = POSIX_ACL_XATTR_ACCESS,
305 .flags = ACL_TYPE_ACCESS,
306 .get = btrfs_xattr_acl_get,
307 .set = btrfs_xattr_acl_set,
310 #else /* CONFIG_BTRFS_FS_POSIX_ACL */
312 int btrfs_acl_chmod(struct inode *inode)
317 int btrfs_init_acl(struct btrfs_trans_handle *trans,
318 struct inode *inode, struct inode *dir)
323 #endif /* CONFIG_BTRFS_FS_POSIX_ACL */