2 * Copyright IBM Corporation, 2010
3 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of version 2.1 of the GNU Lesser General Public License
7 * as published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
15 #include <linux/module.h>
17 #include <net/9p/9p.h>
18 #include <net/9p/client.h>
19 #include <linux/slab.h>
20 #include <linux/sched.h>
21 #include <linux/posix_acl_xattr.h>
26 static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
30 struct posix_acl *acl = NULL;;
32 size = v9fs_fid_xattr_get(fid, name, NULL, 0);
34 value = kzalloc(size, GFP_NOFS);
36 return ERR_PTR(-ENOMEM);
37 size = v9fs_fid_xattr_get(fid, name, value, size);
39 acl = posix_acl_from_xattr(value, size);
43 } else if (size == -ENODATA || size == 0 ||
44 size == -ENOSYS || size == -EOPNOTSUPP) {
54 int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
57 struct posix_acl *pacl, *dacl;
59 /* get the default/access acl values and cache them */
60 dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
61 pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
63 if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
64 set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
65 set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
66 posix_acl_release(dacl);
67 posix_acl_release(pacl);
74 static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
76 struct posix_acl *acl;
78 * 9p Always cache the acl value when
79 * instantiating the inode (v9fs_inode_from_fid)
81 acl = get_cached_acl(inode, type);
82 BUG_ON(acl == ACL_NOT_CACHED);
86 int v9fs_check_acl(struct inode *inode, int mask)
88 struct posix_acl *acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
93 int error = posix_acl_permission(inode, acl, mask);
94 posix_acl_release(acl);
100 static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
101 void *buffer, size_t size, int type)
103 struct posix_acl *acl;
106 if (strcmp(name, "") != 0)
109 acl = v9fs_get_cached_acl(dentry->d_inode, type);
114 error = posix_acl_to_xattr(acl, buffer, size);
115 posix_acl_release(acl);
120 static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
121 const void *value, size_t size,
125 struct posix_acl *acl;
126 struct inode *inode = dentry->d_inode;
128 if (strcmp(name, "") != 0)
130 if (S_ISLNK(inode->i_mode))
132 if (!is_owner_or_cap(inode))
135 /* update the cached acl value */
136 acl = posix_acl_from_xattr(value, size);
140 retval = posix_acl_valid(acl);
148 case ACL_TYPE_ACCESS:
149 name = POSIX_ACL_XATTR_ACCESS;
151 mode_t mode = inode->i_mode;
152 retval = posix_acl_equiv_mode(acl, &mode);
159 * ACL can be represented
160 * by the mode bits. So don't
167 /* Updte the mode bits */
168 iattr.ia_mode = ((mode & S_IALLUGO) |
169 (inode->i_mode & ~S_IALLUGO));
170 iattr.ia_valid = ATTR_MODE;
171 /* FIXME should we update ctime ?
172 * What is the following setxattr update the
175 v9fs_vfs_setattr_dotl(dentry, &iattr);
179 case ACL_TYPE_DEFAULT:
180 name = POSIX_ACL_XATTR_DEFAULT;
181 if (!S_ISDIR(inode->i_mode)) {
189 retval = v9fs_xattr_set(dentry, name, value, size, flags);
191 set_cached_acl(inode, type, acl);
193 posix_acl_release(acl);
197 const struct xattr_handler v9fs_xattr_acl_access_handler = {
198 .prefix = POSIX_ACL_XATTR_ACCESS,
199 .flags = ACL_TYPE_ACCESS,
200 .get = v9fs_xattr_get_acl,
201 .set = v9fs_xattr_set_acl,
204 const struct xattr_handler v9fs_xattr_acl_default_handler = {
205 .prefix = POSIX_ACL_XATTR_DEFAULT,
206 .flags = ACL_TYPE_DEFAULT,
207 .get = v9fs_xattr_get_acl,
208 .set = v9fs_xattr_set_acl,