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/kernel.h>
17 #include <linux/richacl_xattr.h>
20 #include "ext4_jbd2.h"
25 static inline struct richacl *
26 ext4_iget_richacl(struct inode *inode)
28 struct richacl *acl = EXT4_RICHACL_NOT_CACHED;
29 struct ext4_inode_info *ei = EXT4_I(inode);
31 spin_lock(&inode->i_lock);
32 if (ei->i_richacl != EXT4_RICHACL_NOT_CACHED)
33 acl = richacl_get(ei->i_richacl);
34 spin_unlock(&inode->i_lock);
40 ext4_iset_richacl(struct inode *inode, struct richacl *acl)
42 struct ext4_inode_info *ei = EXT4_I(inode);
44 spin_lock(&inode->i_lock);
45 if (ei->i_richacl != EXT4_RICHACL_NOT_CACHED)
46 richacl_put(ei->i_richacl);
47 ei->i_richacl = richacl_get(acl);
48 spin_unlock(&inode->i_lock);
51 static struct richacl *
52 ext4_get_richacl(struct inode *inode)
54 const int name_index = EXT4_XATTR_INDEX_RICHACL;
59 if (!IS_RICHACL(inode))
60 return ERR_PTR(-EOPNOTSUPP);
61 acl = ext4_iget_richacl(inode);
62 if (acl != EXT4_RICHACL_NOT_CACHED)
64 retval = ext4_xattr_get(inode, name_index, "", NULL, 0);
66 value = kmalloc(retval, GFP_KERNEL);
68 return ERR_PTR(-ENOMEM);
69 retval = ext4_xattr_get(inode, name_index, "", value, retval);
72 acl = richacl_from_xattr(value, retval);
73 if (acl == ERR_PTR(-EINVAL))
75 } else if (retval == -ENODATA || retval == -ENOSYS)
78 acl = ERR_PTR(retval);
81 if (!IS_ERR_OR_NULL(acl))
82 ext4_iset_richacl(inode, acl);
88 ext4_set_richacl(handle_t *handle, struct inode *inode, struct richacl *acl)
90 const int name_index = EXT4_XATTR_INDEX_RICHACL;
96 mode_t mode = inode->i_mode;
97 if (richacl_equiv_mode(acl, &mode) == 0) {
99 ext4_mark_inode_dirty(handle, inode);
104 size = richacl_xattr_size(acl);
105 value = kmalloc(size, GFP_KERNEL);
108 richacl_to_xattr(acl, value);
111 retval = ext4_xattr_set_handle(handle, inode, name_index, "",
114 retval = ext4_xattr_set(inode, name_index, "", value, size, 0);
117 ext4_iset_richacl(inode, acl);
123 ext4_richacl_permission(struct inode *inode, unsigned int mask)
128 if (!IS_RICHACL(inode))
131 acl = ext4_get_richacl(inode);
132 if (acl && IS_ERR(acl))
133 retval = PTR_ERR(acl);
135 retval = richacl_inode_permission(inode, acl, mask);
142 int ext4_permission(struct inode *inode, int mask)
144 if (IS_RICHACL(inode))
145 return ext4_richacl_permission(inode,
146 richacl_want_to_mask(mask));
148 return generic_permission(inode, mask);
151 int ext4_may_create(struct inode *dir, int isdir)
153 return richacl_may_create(dir, isdir, ext4_richacl_permission);
156 int ext4_may_delete(struct inode *dir, struct inode *inode, int replace)
158 return richacl_may_delete(dir, inode, replace, ext4_richacl_permission);
162 ext4_init_richacl(handle_t *handle, struct inode *inode, struct inode *dir)
164 struct richacl *dir_acl = NULL;
166 if (!S_ISLNK(inode->i_mode)) {
167 dir_acl = ext4_get_richacl(dir);
169 return PTR_ERR(dir_acl);
175 acl = richacl_inherit(dir_acl, inode);
176 richacl_put(dir_acl);
178 retval = PTR_ERR(acl);
179 if (acl && !IS_ERR(acl)) {
180 retval = ext4_set_richacl(handle, inode, acl);
185 inode->i_mode &= ~current_umask();
191 ext4_richacl_chmod(struct inode *inode)
196 if (S_ISLNK(inode->i_mode))
198 acl = ext4_get_richacl(inode);
199 if (IS_ERR_OR_NULL(acl))
201 acl = richacl_chmod(acl, inode->i_mode);
204 retval = ext4_set_richacl(NULL, inode, acl);
211 ext4_xattr_list_richacl(struct dentry *dentry, char *list, size_t list_len,
212 const char *name, size_t name_len, int type)
214 const size_t size = sizeof(RICHACL_XATTR);
215 if (!IS_RICHACL(dentry->d_inode))
217 if (list && size <= list_len)
218 memcpy(list, RICHACL_XATTR, size);
223 ext4_xattr_get_richacl(struct dentry *dentry, const char *name, void *buffer,
224 size_t buffer_size, int type)
229 if (strcmp(name, "") != 0)
231 acl = ext4_get_richacl(dentry->d_inode);
236 size = richacl_xattr_size(acl);
238 if (size > buffer_size)
240 richacl_to_xattr(acl, buffer);
248 ext4_xattr_set_richacl(struct dentry *dentry, const char *name,
249 const void *value, size_t size, int flags, int type)
252 struct richacl *acl = NULL;
253 int retval, retries = 0;
254 struct inode *inode = dentry->d_inode;
256 if (!IS_RICHACL(dentry->d_inode))
258 if (S_ISLNK(inode->i_mode))
260 if (strcmp(name, "") != 0)
262 if (current_fsuid() != inode->i_uid &&
263 ext4_richacl_permission(inode, ACE4_WRITE_ACL) &&
264 !capable(CAP_FOWNER))
267 acl = richacl_from_xattr(value, size);
271 inode->i_mode &= ~S_IRWXUGO;
272 inode->i_mode |= richacl_masks_to_mode(acl);
276 handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
278 return PTR_ERR(handle);
279 ext4_mark_inode_dirty(handle, inode);
280 retval = ext4_set_richacl(handle, inode, acl);
281 ext4_journal_stop(handle);
282 if (retval == ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
288 const struct xattr_handler ext4_richacl_xattr_handler = {
289 .prefix = RICHACL_XATTR,
290 .list = ext4_xattr_list_richacl,
291 .get = ext4_xattr_get_richacl,
292 .set = ext4_xattr_set_richacl,