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/sched/mm.h>
26 #include <linux/slab.h>
29 #include "btrfs_inode.h"
32 struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
37 struct posix_acl *acl;
41 name = XATTR_NAME_POSIX_ACL_ACCESS;
43 case ACL_TYPE_DEFAULT:
44 name = XATTR_NAME_POSIX_ACL_DEFAULT;
50 size = __btrfs_getxattr(inode, name, "", 0);
52 value = kzalloc(size, GFP_KERNEL);
54 return ERR_PTR(-ENOMEM);
55 size = __btrfs_getxattr(inode, name, value, size);
58 acl = posix_acl_from_xattr(&init_user_ns, value, size);
59 } else if (size == -ERANGE || size == -ENODATA || size == 0) {
70 * Needs to be called with fs_mutex held
72 static int __btrfs_set_acl(struct btrfs_trans_handle *trans,
73 struct inode *inode, struct posix_acl *acl, int type)
81 name = XATTR_NAME_POSIX_ACL_ACCESS;
83 case ACL_TYPE_DEFAULT:
84 if (!S_ISDIR(inode->i_mode))
85 return acl ? -EINVAL : 0;
86 name = XATTR_NAME_POSIX_ACL_DEFAULT;
93 unsigned int nofs_flag;
95 size = posix_acl_xattr_size(acl->a_count);
97 * We're holding a transaction handle, so use a NOFS memory
98 * allocation context to avoid deadlock if reclaim happens.
100 nofs_flag = memalloc_nofs_save();
101 value = kmalloc(size, GFP_KERNEL);
102 memalloc_nofs_restore(nofs_flag);
108 ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
113 ret = __btrfs_setxattr(trans, inode, name, value, size, 0);
118 set_cached_acl(inode, type, acl);
123 int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
126 umode_t old_mode = inode->i_mode;
128 if (type == ACL_TYPE_ACCESS && acl) {
129 ret = posix_acl_update_mode(inode, &inode->i_mode, &acl);
133 ret = __btrfs_set_acl(NULL, inode, acl, type);
135 inode->i_mode = old_mode;
140 * btrfs_init_acl is already generally called under fs_mutex, so the locking
141 * stuff has been fixed to work with that. If the locking stuff changes, we
142 * need to re-evaluate the acl locking stuff.
144 int btrfs_init_acl(struct btrfs_trans_handle *trans,
145 struct inode *inode, struct inode *dir)
147 struct posix_acl *default_acl, *acl;
150 /* this happens with subvols */
154 ret = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
159 ret = __btrfs_set_acl(trans, inode, default_acl,
161 posix_acl_release(default_acl);
166 ret = __btrfs_set_acl(trans, inode, acl,
168 posix_acl_release(acl);
171 if (!default_acl && !acl)