2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/xattr.h>
16 #include <linux/posix_acl.h>
17 #include <linux/posix_acl_xattr.h>
18 #include <linux/gfs2_ondisk.h>
30 static const char *gfs2_acl_name(int type)
34 return GFS2_POSIX_ACL_ACCESS;
35 case ACL_TYPE_DEFAULT:
36 return GFS2_POSIX_ACL_DEFAULT;
41 static struct posix_acl *gfs2_acl_get(struct gfs2_inode *ip, int type)
43 struct posix_acl *acl;
51 acl = get_cached_acl(&ip->i_inode, type);
52 if (acl != ACL_NOT_CACHED)
55 name = gfs2_acl_name(type);
57 return ERR_PTR(-EINVAL);
59 len = gfs2_xattr_acl_get(ip, name, &data);
65 acl = posix_acl_from_xattr(data, len);
71 * gfs2_check_acl - Check an ACL to see if we're allowed to do something
72 * @inode: the file we want to do something to
73 * @mask: what we want to do
78 int gfs2_check_acl(struct inode *inode, int mask)
80 struct posix_acl *acl;
83 acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS);
88 error = posix_acl_permission(inode, acl, mask);
89 posix_acl_release(acl);
96 static int gfs2_set_mode(struct inode *inode, mode_t mode)
100 if (mode != inode->i_mode) {
103 iattr.ia_valid = ATTR_MODE;
104 iattr.ia_mode = mode;
106 error = gfs2_setattr_simple(GFS2_I(inode), &iattr);
112 static int gfs2_acl_set(struct inode *inode, int type, struct posix_acl *acl)
117 const char *name = gfs2_acl_name(type);
119 BUG_ON(name == NULL);
120 len = posix_acl_to_xattr(acl, NULL, 0);
123 data = kmalloc(len, GFP_NOFS);
126 error = posix_acl_to_xattr(acl, data, len);
129 error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
131 set_cached_acl(inode, type, acl);
137 int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode)
139 struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
140 struct posix_acl *acl, *clone;
141 mode_t mode = inode->i_mode;
144 if (!sdp->sd_args.ar_posix_acl)
146 if (S_ISLNK(inode->i_mode))
149 acl = gfs2_acl_get(dip, ACL_TYPE_DEFAULT);
153 mode &= ~current_umask();
154 if (mode != inode->i_mode)
155 error = gfs2_set_mode(inode, mode);
159 if (S_ISDIR(inode->i_mode)) {
160 error = gfs2_acl_set(inode, ACL_TYPE_DEFAULT, acl);
165 clone = posix_acl_clone(acl, GFP_NOFS);
169 posix_acl_release(acl);
172 error = posix_acl_create_masq(acl, &mode);
178 error = gfs2_acl_set(inode, ACL_TYPE_ACCESS, acl);
182 error = gfs2_set_mode(inode, mode);
184 posix_acl_release(acl);
188 int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
190 struct posix_acl *acl, *clone;
195 acl = gfs2_acl_get(ip, ACL_TYPE_ACCESS);
199 return gfs2_setattr_simple(ip, attr);
201 clone = posix_acl_clone(acl, GFP_NOFS);
205 posix_acl_release(acl);
208 error = posix_acl_chmod_masq(acl, attr->ia_mode);
210 len = posix_acl_to_xattr(acl, NULL, 0);
211 data = kmalloc(len, GFP_NOFS);
215 posix_acl_to_xattr(acl, data, len);
216 error = gfs2_xattr_acl_chmod(ip, attr, data);
218 set_cached_acl(&ip->i_inode, ACL_TYPE_ACCESS, acl);
222 posix_acl_release(acl);
226 static int gfs2_acl_type(const char *name)
228 if (strcmp(name, GFS2_POSIX_ACL_ACCESS) == 0)
229 return ACL_TYPE_ACCESS;
230 if (strcmp(name, GFS2_POSIX_ACL_DEFAULT) == 0)
231 return ACL_TYPE_DEFAULT;
235 static int gfs2_xattr_system_get(struct dentry *dentry, const char *name,
236 void *buffer, size_t size, int xtype)
238 struct inode *inode = dentry->d_inode;
239 struct posix_acl *acl;
243 type = gfs2_acl_type(name);
247 acl = gfs2_acl_get(GFS2_I(inode), type);
253 error = posix_acl_to_xattr(acl, buffer, size);
254 posix_acl_release(acl);
259 static int gfs2_xattr_system_set(struct dentry *dentry, const char *name,
260 const void *value, size_t size, int flags,
263 struct inode *inode = dentry->d_inode;
264 struct gfs2_sbd *sdp = GFS2_SB(inode);
265 struct posix_acl *acl = NULL;
268 if (!sdp->sd_args.ar_posix_acl)
271 type = gfs2_acl_type(name);
274 if (flags & XATTR_CREATE)
276 if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
277 return value ? -EACCES : 0;
278 if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
280 if (S_ISLNK(inode->i_mode))
286 acl = posix_acl_from_xattr(value, size);
289 * acl_set_file(3) may request that we set default ACLs with
290 * zero length -- defend (gracefully) against that here.
295 error = PTR_ERR(acl);
299 error = posix_acl_valid(acl);
304 if (acl->a_count > GFS2_ACL_MAX_ENTRIES)
307 if (type == ACL_TYPE_ACCESS) {
308 mode_t mode = inode->i_mode;
309 error = posix_acl_equiv_mode(acl, &mode);
312 posix_acl_release(acl);
319 error = gfs2_set_mode(inode, mode);
325 error = __gfs2_xattr_set(inode, name, value, size, 0, GFS2_EATYPE_SYS);
328 set_cached_acl(inode, type, acl);
330 forget_cached_acl(inode, type);
333 posix_acl_release(acl);
338 struct xattr_handler gfs2_xattr_system_handler = {
339 .prefix = XATTR_SYSTEM_PREFIX,
340 .flags = GFS2_EATYPE_SYS,
341 .get = gfs2_xattr_system_get,
342 .set = gfs2_xattr_system_set,