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>
28 static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
32 struct posix_acl *acl = NULL;
34 size = v9fs_fid_xattr_get(fid, name, NULL, 0);
36 value = kzalloc(size, GFP_NOFS);
38 return ERR_PTR(-ENOMEM);
39 size = v9fs_fid_xattr_get(fid, name, value, size);
41 acl = posix_acl_from_xattr(&init_user_ns, value, size);
45 } else if (size == -ENODATA || size == 0 ||
46 size == -ENOSYS || size == -EOPNOTSUPP) {
56 int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
59 struct posix_acl *pacl, *dacl;
60 struct v9fs_session_info *v9ses;
62 v9ses = v9fs_inode2v9ses(inode);
63 if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
64 ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
65 set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
66 set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
69 /* get the default/access acl values and cache them */
70 dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
71 pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
73 if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
74 set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
75 set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
80 posix_acl_release(dacl);
83 posix_acl_release(pacl);
88 static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
90 struct posix_acl *acl;
92 * 9p Always cache the acl value when
93 * instantiating the inode (v9fs_inode_from_fid)
95 acl = get_cached_acl(inode, type);
96 BUG_ON(acl == ACL_NOT_CACHED);
100 struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
102 struct v9fs_session_info *v9ses;
104 v9ses = v9fs_inode2v9ses(inode);
105 if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
106 ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
108 * On access = client and acl = on mode get the acl
109 * values from the server
113 return v9fs_get_cached_acl(inode, type);
117 static int v9fs_set_acl(struct p9_fid *fid, int type, struct posix_acl *acl)
126 /* Set a setxattr request to server */
127 size = posix_acl_xattr_size(acl->a_count);
128 buffer = kmalloc(size, GFP_KERNEL);
131 retval = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
135 case ACL_TYPE_ACCESS:
136 name = POSIX_ACL_XATTR_ACCESS;
138 case ACL_TYPE_DEFAULT:
139 name = POSIX_ACL_XATTR_DEFAULT;
144 retval = v9fs_fid_xattr_set(fid, name, buffer, size, 0);
150 int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid)
153 struct posix_acl *acl;
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(fid, 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 struct p9_fid *fid = v9fs_fid_lookup(dentry);
174 set_cached_acl(dentry->d_inode, ACL_TYPE_DEFAULT, *dpacl);
175 set_cached_acl(dentry->d_inode, ACL_TYPE_ACCESS, *pacl);
177 v9fs_set_acl(fid, ACL_TYPE_DEFAULT, *dpacl);
178 v9fs_set_acl(fid, ACL_TYPE_ACCESS, *pacl);
181 posix_acl_release(*dpacl);
182 posix_acl_release(*pacl);
183 *dpacl = *pacl = NULL;
187 int v9fs_acl_mode(struct inode *dir, umode_t *modep,
188 struct posix_acl **dpacl, struct posix_acl **pacl)
191 umode_t mode = *modep;
192 struct posix_acl *acl = NULL;
194 if (!S_ISLNK(mode)) {
195 acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
199 mode &= ~current_umask();
203 *dpacl = posix_acl_dup(acl);
204 retval = posix_acl_create(&acl, GFP_NOFS, &mode);
210 posix_acl_release(acl);
216 static int v9fs_remote_get_acl(struct dentry *dentry, const char *name,
217 void *buffer, size_t size, int type)
222 case ACL_TYPE_ACCESS:
223 full_name = POSIX_ACL_XATTR_ACCESS;
225 case ACL_TYPE_DEFAULT:
226 full_name = POSIX_ACL_XATTR_DEFAULT;
231 return v9fs_xattr_get(dentry, full_name, buffer, size);
234 static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
235 void *buffer, size_t size, int type)
237 struct v9fs_session_info *v9ses;
238 struct posix_acl *acl;
241 if (strcmp(name, "") != 0)
244 v9ses = v9fs_dentry2v9ses(dentry);
246 * We allow set/get/list of acl when access=client is not specified
248 if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
249 return v9fs_remote_get_acl(dentry, name, buffer, size, type);
251 acl = v9fs_get_cached_acl(dentry->d_inode, type);
256 error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
257 posix_acl_release(acl);
262 static int v9fs_remote_set_acl(struct dentry *dentry, const char *name,
263 const void *value, size_t size,
269 case ACL_TYPE_ACCESS:
270 full_name = POSIX_ACL_XATTR_ACCESS;
272 case ACL_TYPE_DEFAULT:
273 full_name = POSIX_ACL_XATTR_DEFAULT;
278 return v9fs_xattr_set(dentry, full_name, value, size, flags);
282 static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
283 const void *value, size_t size,
287 struct posix_acl *acl;
288 struct v9fs_session_info *v9ses;
289 struct inode *inode = dentry->d_inode;
291 if (strcmp(name, "") != 0)
294 v9ses = v9fs_dentry2v9ses(dentry);
296 * set the attribute on the remote. Without even looking at the
297 * xattr value. We leave it to the server to validate
299 if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
300 return v9fs_remote_set_acl(dentry, name,
301 value, size, flags, type);
303 if (S_ISLNK(inode->i_mode))
305 if (!inode_owner_or_capable(inode))
308 /* update the cached acl value */
309 acl = posix_acl_from_xattr(&init_user_ns, value, size);
313 retval = posix_acl_valid(acl);
321 case ACL_TYPE_ACCESS:
322 name = POSIX_ACL_XATTR_ACCESS;
324 umode_t mode = inode->i_mode;
325 retval = posix_acl_equiv_mode(acl, &mode);
332 * ACL can be represented
333 * by the mode bits. So don't
340 /* Updte the mode bits */
341 iattr.ia_mode = ((mode & S_IALLUGO) |
342 (inode->i_mode & ~S_IALLUGO));
343 iattr.ia_valid = ATTR_MODE;
344 /* FIXME should we update ctime ?
345 * What is the following setxattr update the
348 v9fs_vfs_setattr_dotl(dentry, &iattr);
352 case ACL_TYPE_DEFAULT:
353 name = POSIX_ACL_XATTR_DEFAULT;
354 if (!S_ISDIR(inode->i_mode)) {
355 retval = acl ? -EINVAL : 0;
362 retval = v9fs_xattr_set(dentry, name, value, size, flags);
364 set_cached_acl(inode, type, acl);
366 posix_acl_release(acl);
370 const struct xattr_handler v9fs_xattr_acl_access_handler = {
371 .prefix = POSIX_ACL_XATTR_ACCESS,
372 .flags = ACL_TYPE_ACCESS,
373 .get = v9fs_xattr_get_acl,
374 .set = v9fs_xattr_set_acl,
377 const struct xattr_handler v9fs_xattr_acl_default_handler = {
378 .prefix = POSIX_ACL_XATTR_DEFAULT,
379 .flags = ACL_TYPE_DEFAULT,
380 .get = v9fs_xattr_get_acl,
381 .set = v9fs_xattr_set_acl,