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>
27 static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
31 struct posix_acl *acl = NULL;
33 size = v9fs_fid_xattr_get(fid, name, NULL, 0);
35 value = kzalloc(size, GFP_NOFS);
37 return ERR_PTR(-ENOMEM);
38 size = v9fs_fid_xattr_get(fid, name, value, size);
40 acl = posix_acl_from_xattr(&init_user_ns, value, size);
44 } else if (size == -ENODATA || size == 0 ||
45 size == -ENOSYS || size == -EOPNOTSUPP) {
55 int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
58 struct posix_acl *pacl, *dacl;
59 struct v9fs_session_info *v9ses;
61 v9ses = v9fs_inode2v9ses(inode);
62 if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
63 ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
64 set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
65 set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
68 /* get the default/access acl values and cache them */
69 dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
70 pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
72 if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
73 set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
74 set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
79 posix_acl_release(dacl);
82 posix_acl_release(pacl);
87 static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
89 struct posix_acl *acl;
91 * 9p Always cache the acl value when
92 * instantiating the inode (v9fs_inode_from_fid)
94 acl = get_cached_acl(inode, type);
95 BUG_ON(acl == ACL_NOT_CACHED);
99 struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
101 struct v9fs_session_info *v9ses;
103 v9ses = v9fs_inode2v9ses(inode);
104 if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
105 ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
107 * On access = client and acl = on mode get the acl
108 * values from the server
112 return v9fs_get_cached_acl(inode, type);
116 static int v9fs_set_acl(struct dentry *dentry, int type, struct posix_acl *acl)
125 /* Set a setxattr request to server */
126 size = posix_acl_xattr_size(acl->a_count);
127 buffer = kmalloc(size, GFP_KERNEL);
130 retval = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
134 case ACL_TYPE_ACCESS:
135 name = POSIX_ACL_XATTR_ACCESS;
137 case ACL_TYPE_DEFAULT:
138 name = POSIX_ACL_XATTR_DEFAULT;
143 retval = v9fs_xattr_set(dentry, name, buffer, size, 0);
149 int v9fs_acl_chmod(struct dentry *dentry)
152 struct posix_acl *acl;
153 struct inode *inode = dentry->d_inode;
155 if (S_ISLNK(inode->i_mode))
157 acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
159 retval = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
162 set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
163 retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, acl);
164 posix_acl_release(acl);
169 int v9fs_set_create_acl(struct dentry *dentry,
170 struct posix_acl **dpacl, struct posix_acl **pacl)
173 set_cached_acl(dentry->d_inode, ACL_TYPE_DEFAULT, *dpacl);
174 v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
175 set_cached_acl(dentry->d_inode, ACL_TYPE_ACCESS, *pacl);
176 v9fs_set_acl(dentry, ACL_TYPE_ACCESS, *pacl);
178 posix_acl_release(*dpacl);
179 posix_acl_release(*pacl);
180 *dpacl = *pacl = NULL;
184 int v9fs_acl_mode(struct inode *dir, umode_t *modep,
185 struct posix_acl **dpacl, struct posix_acl **pacl)
188 umode_t mode = *modep;
189 struct posix_acl *acl = NULL;
191 if (!S_ISLNK(mode)) {
192 acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
196 mode &= ~current_umask();
200 *dpacl = posix_acl_dup(acl);
201 retval = posix_acl_create(&acl, GFP_NOFS, &mode);
207 posix_acl_release(acl);
213 static int v9fs_remote_get_acl(struct dentry *dentry, const char *name,
214 void *buffer, size_t size, int type)
219 case ACL_TYPE_ACCESS:
220 full_name = POSIX_ACL_XATTR_ACCESS;
222 case ACL_TYPE_DEFAULT:
223 full_name = POSIX_ACL_XATTR_DEFAULT;
228 return v9fs_xattr_get(dentry, full_name, buffer, size);
231 static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
232 void *buffer, size_t size, int type)
234 struct v9fs_session_info *v9ses;
235 struct posix_acl *acl;
238 if (strcmp(name, "") != 0)
241 v9ses = v9fs_dentry2v9ses(dentry);
243 * We allow set/get/list of acl when access=client is not specified
245 if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
246 return v9fs_remote_get_acl(dentry, name, buffer, size, type);
248 acl = v9fs_get_cached_acl(dentry->d_inode, type);
253 error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
254 posix_acl_release(acl);
259 static int v9fs_remote_set_acl(struct dentry *dentry, const char *name,
260 const void *value, size_t size,
266 case ACL_TYPE_ACCESS:
267 full_name = POSIX_ACL_XATTR_ACCESS;
269 case ACL_TYPE_DEFAULT:
270 full_name = POSIX_ACL_XATTR_DEFAULT;
275 return v9fs_xattr_set(dentry, full_name, value, size, flags);
279 static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
280 const void *value, size_t size,
284 struct posix_acl *acl;
285 struct v9fs_session_info *v9ses;
286 struct inode *inode = dentry->d_inode;
288 if (strcmp(name, "") != 0)
291 v9ses = v9fs_dentry2v9ses(dentry);
293 * set the attribute on the remote. Without even looking at the
294 * xattr value. We leave it to the server to validate
296 if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
297 return v9fs_remote_set_acl(dentry, name,
298 value, size, flags, type);
300 if (S_ISLNK(inode->i_mode))
302 if (!inode_owner_or_capable(inode))
305 /* update the cached acl value */
306 acl = posix_acl_from_xattr(&init_user_ns, value, size);
310 retval = posix_acl_valid(acl);
318 case ACL_TYPE_ACCESS:
319 name = POSIX_ACL_XATTR_ACCESS;
321 umode_t mode = inode->i_mode;
322 retval = posix_acl_equiv_mode(acl, &mode);
329 * ACL can be represented
330 * by the mode bits. So don't
337 /* Updte the mode bits */
338 iattr.ia_mode = ((mode & S_IALLUGO) |
339 (inode->i_mode & ~S_IALLUGO));
340 iattr.ia_valid = ATTR_MODE;
341 /* FIXME should we update ctime ?
342 * What is the following setxattr update the
345 v9fs_vfs_setattr_dotl(dentry, &iattr);
349 case ACL_TYPE_DEFAULT:
350 name = POSIX_ACL_XATTR_DEFAULT;
351 if (!S_ISDIR(inode->i_mode)) {
352 retval = acl ? -EINVAL : 0;
359 retval = v9fs_xattr_set(dentry, name, value, size, flags);
361 set_cached_acl(inode, type, acl);
363 posix_acl_release(acl);
367 const struct xattr_handler v9fs_xattr_acl_access_handler = {
368 .prefix = POSIX_ACL_XATTR_ACCESS,
369 .flags = ACL_TYPE_ACCESS,
370 .get = v9fs_xattr_get_acl,
371 .set = v9fs_xattr_set_acl,
374 const struct xattr_handler v9fs_xattr_acl_default_handler = {
375 .prefix = POSIX_ACL_XATTR_DEFAULT,
376 .flags = ACL_TYPE_DEFAULT,
377 .get = v9fs_xattr_get_acl,
378 .set = v9fs_xattr_set_acl,