xref: /openbmc/linux/fs/jfs/acl.c (revision bc5aa3a0)
1 /*
2  *   Copyright (C) International Business Machines  Corp., 2002-2004
3  *   Copyright (C) Andreas Gruenbacher, 2001
4  *   Copyright (C) Linus Torvalds, 1991, 1992
5  *
6  *   This program is free software;  you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
14  *   the GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program;  if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  */
20 
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/fs.h>
24 #include <linux/posix_acl_xattr.h>
25 #include "jfs_incore.h"
26 #include "jfs_txnmgr.h"
27 #include "jfs_xattr.h"
28 #include "jfs_acl.h"
29 
30 struct posix_acl *jfs_get_acl(struct inode *inode, int type)
31 {
32 	struct posix_acl *acl;
33 	char *ea_name;
34 	int size;
35 	char *value = NULL;
36 
37 	switch(type) {
38 		case ACL_TYPE_ACCESS:
39 			ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
40 			break;
41 		case ACL_TYPE_DEFAULT:
42 			ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
43 			break;
44 		default:
45 			return ERR_PTR(-EINVAL);
46 	}
47 
48 	size = __jfs_getxattr(inode, ea_name, NULL, 0);
49 
50 	if (size > 0) {
51 		value = kmalloc(size, GFP_KERNEL);
52 		if (!value)
53 			return ERR_PTR(-ENOMEM);
54 		size = __jfs_getxattr(inode, ea_name, value, size);
55 	}
56 
57 	if (size < 0) {
58 		if (size == -ENODATA)
59 			acl = NULL;
60 		else
61 			acl = ERR_PTR(size);
62 	} else {
63 		acl = posix_acl_from_xattr(&init_user_ns, value, size);
64 	}
65 	kfree(value);
66 	return acl;
67 }
68 
69 static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
70 		       struct posix_acl *acl)
71 {
72 	char *ea_name;
73 	int rc;
74 	int size = 0;
75 	char *value = NULL;
76 
77 	switch (type) {
78 	case ACL_TYPE_ACCESS:
79 		ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
80 		if (acl) {
81 			rc = posix_acl_equiv_mode(acl, &inode->i_mode);
82 			if (rc < 0)
83 				return rc;
84 			inode->i_ctime = CURRENT_TIME;
85 			mark_inode_dirty(inode);
86 			if (rc == 0)
87 				acl = NULL;
88 		}
89 		break;
90 	case ACL_TYPE_DEFAULT:
91 		ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
92 		break;
93 	default:
94 		return -EINVAL;
95 	}
96 
97 	if (acl) {
98 		size = posix_acl_xattr_size(acl->a_count);
99 		value = kmalloc(size, GFP_KERNEL);
100 		if (!value)
101 			return -ENOMEM;
102 		rc = posix_acl_to_xattr(&init_user_ns, acl, value, size);
103 		if (rc < 0)
104 			goto out;
105 	}
106 	rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
107 out:
108 	kfree(value);
109 
110 	if (!rc)
111 		set_cached_acl(inode, type, acl);
112 
113 	return rc;
114 }
115 
116 int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
117 {
118 	int rc;
119 	tid_t tid;
120 
121 	tid = txBegin(inode->i_sb, 0);
122 	mutex_lock(&JFS_IP(inode)->commit_mutex);
123 	rc = __jfs_set_acl(tid, inode, type, acl);
124 	if (!rc)
125 		rc = txCommit(tid, 1, &inode, 0);
126 	txEnd(tid);
127 	mutex_unlock(&JFS_IP(inode)->commit_mutex);
128 	return rc;
129 }
130 
131 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
132 {
133 	struct posix_acl *default_acl, *acl;
134 	int rc = 0;
135 
136 	rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
137 	if (rc)
138 		return rc;
139 
140 	if (default_acl) {
141 		rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
142 		posix_acl_release(default_acl);
143 	}
144 
145 	if (acl) {
146 		if (!rc)
147 			rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
148 		posix_acl_release(acl);
149 	}
150 
151 	JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
152 			       inode->i_mode;
153 
154 	return rc;
155 }
156