blob: 58aa8e75f7f5a8de1608dd7df0d6e4cf707d7a54 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/reiserfs/xattr.c
3 *
4 * Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com>
5 *
6 */
7
8/*
9 * In order to implement EA/ACLs in a clean, backwards compatible manner,
10 * they are implemented as files in a "private" directory.
11 * Each EA is in it's own file, with the directory layout like so (/ is assumed
12 * to be relative to fs root). Inside the /.reiserfs_priv/xattrs directory,
13 * directories named using the capital-hex form of the objectid and
14 * generation number are used. Inside each directory are individual files
15 * named with the name of the extended attribute.
16 *
17 * So, for objectid 12648430, we could have:
18 * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_access
19 * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_default
20 * /.reiserfs_priv/xattrs/C0FFEE.0/user.Content-Type
21 * .. or similar.
22 *
23 * The file contents are the text of the EA. The size is known based on the
24 * stat data describing the file.
25 *
26 * In the case of system.posix_acl_access and system.posix_acl_default, since
27 * these are special cases for filesystem ACLs, they are interpreted by the
28 * kernel, in addition, they are negatively and positively cached and attached
29 * to the inode so that unnecessary lookups are avoided.
Jeff Mahoneyd9845612009-03-30 14:02:35 -040030 *
31 * Locking works like so:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -040032 * Directory components (xattr root, xattr dir) are protectd by their i_mutex.
33 * The xattrs themselves are protected by the xattr_sem.
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 */
35
36#include <linux/reiserfs_fs.h>
Randy Dunlap16f7e0f2006-01-11 12:17:46 -080037#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <linux/dcache.h>
39#include <linux/namei.h>
40#include <linux/errno.h>
41#include <linux/fs.h>
42#include <linux/file.h>
43#include <linux/pagemap.h>
44#include <linux/xattr.h>
45#include <linux/reiserfs_xattr.h>
46#include <linux/reiserfs_acl.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#include <asm/uaccess.h>
Al Viro3277c392006-11-14 21:13:53 -080048#include <net/checksum.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <linux/stat.h>
Jeff Mahoney6c176752009-03-30 14:02:34 -040050#include <linux/quotaops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Linus Torvalds1da177e2005-04-16 15:20:36 -070052#define PRIVROOT_NAME ".reiserfs_priv"
53#define XAROOT_NAME "xattrs"
54
Linus Torvalds1da177e2005-04-16 15:20:36 -070055
Jeff Mahoney6c176752009-03-30 14:02:34 -040056/* Helpers for inode ops. We do this so that we don't have all the VFS
57 * overhead and also for proper i_mutex annotation.
58 * dir->i_mutex must be held for all of them. */
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040059#ifdef CONFIG_REISERFS_FS_XATTR
Jeff Mahoney6c176752009-03-30 14:02:34 -040060static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070061{
Jeff Mahoney6c176752009-03-30 14:02:34 -040062 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070063 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040064 return dir->i_op->create(dir, dentry, mode, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065}
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040066#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Jeff Mahoney6c176752009-03-30 14:02:34 -040068static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode)
69{
70 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070071 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040072 return dir->i_op->mkdir(dir, dentry, mode);
73}
74
75/* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
76 * mutation ops aren't called during rename or splace, which are the
77 * only other users of I_MUTEX_CHILD. It violates the ordering, but that's
78 * better than allocating another subclass just for this code. */
79static int xattr_unlink(struct inode *dir, struct dentry *dentry)
80{
81 int error;
82 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070083 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040084
85 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
86 error = dir->i_op->unlink(dir, dentry);
87 mutex_unlock(&dentry->d_inode->i_mutex);
88
89 if (!error)
90 d_delete(dentry);
91 return error;
92}
93
94static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
95{
96 int error;
97 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070098 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040099
100 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
101 dentry_unhash(dentry);
102 error = dir->i_op->rmdir(dir, dentry);
103 if (!error)
104 dentry->d_inode->i_flags |= S_DEAD;
105 mutex_unlock(&dentry->d_inode->i_mutex);
106 if (!error)
107 d_delete(dentry);
108 dput(dentry);
109
110 return error;
111}
112
Jeff Mahoney6c176752009-03-30 14:02:34 -0400113#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
114
Jeff Mahoney6c176752009-03-30 14:02:34 -0400115static struct dentry *open_xa_root(struct super_block *sb, int flags)
116{
117 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400118 struct dentry *xaroot;
119 if (!privroot->d_inode)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400120 return ERR_PTR(-ENODATA);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400121
122 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
123
124 xaroot = dget(REISERFS_SB(sb)->xattr_root);
Jeff Mahoneyceb5edc2009-05-17 01:02:02 -0400125 if (!xaroot)
126 xaroot = ERR_PTR(-ENODATA);
127 else if (!xaroot->d_inode) {
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400128 int err = -ENODATA;
129 if (xattr_may_create(flags))
130 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
131 if (err) {
132 dput(xaroot);
133 xaroot = ERR_PTR(err);
134 }
135 }
136
137 mutex_unlock(&privroot->d_inode->i_mutex);
138 return xaroot;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400139}
140
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700141static struct dentry *open_xa_dir(const struct inode *inode, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700143 struct dentry *xaroot, *xadir;
144 char namebuf[17];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
Jeff Mahoney6c176752009-03-30 14:02:34 -0400146 xaroot = open_xa_root(inode->i_sb, flags);
Jeff Mahoney9b7f3752007-04-23 14:41:17 -0700147 if (IS_ERR(xaroot))
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700148 return xaroot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700150 snprintf(namebuf, sizeof(namebuf), "%X.%X",
151 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
152 inode->i_generation);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400154 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
155
156 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
157 if (!IS_ERR(xadir) && !xadir->d_inode) {
158 int err = -ENODATA;
159 if (xattr_may_create(flags))
160 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
161 if (err) {
162 dput(xadir);
163 xadir = ERR_PTR(err);
164 }
165 }
166
167 mutex_unlock(&xaroot->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700168 dput(xaroot);
169 return xadir;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170}
171
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400172/* The following are side effects of other operations that aren't explicitly
173 * modifying extended attributes. This includes operations such as permissions
174 * or ownership changes, object deletions, etc. */
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400175struct reiserfs_dentry_buf {
176 struct dentry *xadir;
177 int count;
178 struct dentry *dentries[8];
179};
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400180
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400181static int
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400182fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
183 u64 ino, unsigned int d_type)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400184{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400185 struct reiserfs_dentry_buf *dbuf = buf;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400186 struct dentry *dentry;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400187 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400188
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400189 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
190 return -ENOSPC;
191
192 if (name[0] == '.' && (name[1] == '\0' ||
193 (name[1] == '.' && name[2] == '\0')))
194 return 0;
195
196 dentry = lookup_one_len(name, dbuf->xadir, namelen);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400197 if (IS_ERR(dentry)) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400198 return PTR_ERR(dentry);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400199 } else if (!dentry->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400200 /* A directory entry exists, but no file? */
201 reiserfs_error(dentry->d_sb, "xattr-20003",
202 "Corrupted directory: xattr %s listed but "
203 "not found for file %s.\n",
204 dentry->d_name.name, dbuf->xadir->d_name.name);
205 dput(dentry);
206 return -EIO;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400207 }
208
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400209 dbuf->dentries[dbuf->count++] = dentry;
210 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400211}
212
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400213static void
214cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400215{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400216 int i;
217 for (i = 0; i < buf->count; i++)
218 if (buf->dentries[i])
219 dput(buf->dentries[i]);
220}
221
222static int reiserfs_for_each_xattr(struct inode *inode,
223 int (*action)(struct dentry *, void *),
224 void *data)
225{
226 struct dentry *dir;
227 int i, err = 0;
228 loff_t pos = 0;
229 struct reiserfs_dentry_buf buf = {
230 .count = 0,
231 };
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400232
233 /* Skip out, an xattr has no xattrs associated with it */
234 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
235 return 0;
236
Jeff Mahoney6c176752009-03-30 14:02:34 -0400237 dir = open_xa_dir(inode, XATTR_REPLACE);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400238 if (IS_ERR(dir)) {
239 err = PTR_ERR(dir);
240 goto out;
241 } else if (!dir->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400242 err = 0;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400243 goto out_dir;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400244 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400245
Jeff Mahoney6c176752009-03-30 14:02:34 -0400246 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400247 buf.xadir = dir;
248 err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
249 while ((err == 0 || err == -ENOSPC) && buf.count) {
250 err = 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400251
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400252 for (i = 0; i < buf.count && buf.dentries[i]; i++) {
253 int lerr = 0;
254 struct dentry *dentry = buf.dentries[i];
255
256 if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
257 lerr = action(dentry, data);
258
259 dput(dentry);
260 buf.dentries[i] = NULL;
261 err = lerr ?: err;
262 }
263 buf.count = 0;
264 if (!err)
265 err = reiserfs_readdir_dentry(dir, &buf,
266 fill_with_dentries, &pos);
267 }
Jeff Mahoney6c176752009-03-30 14:02:34 -0400268 mutex_unlock(&dir->d_inode->i_mutex);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400269
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400270 /* Clean up after a failed readdir */
271 cleanup_dentry_buf(&buf);
272
273 if (!err) {
274 /* We start a transaction here to avoid a ABBA situation
275 * between the xattr root's i_mutex and the journal lock.
276 * This doesn't incur much additional overhead since the
277 * new transaction will just nest inside the
278 * outer transaction. */
279 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
280 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
281 struct reiserfs_transaction_handle th;
282 err = journal_begin(&th, inode->i_sb, blocks);
283 if (!err) {
284 int jerror;
285 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
286 I_MUTEX_XATTR);
287 err = action(dir, data);
288 jerror = journal_end(&th, inode->i_sb, blocks);
289 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
290 err = jerror ?: err;
291 }
292 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400293out_dir:
294 dput(dir);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400295out:
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400296 /* -ENODATA isn't an error */
297 if (err == -ENODATA)
298 err = 0;
299 return err;
300}
301
302static int delete_one_xattr(struct dentry *dentry, void *data)
303{
304 struct inode *dir = dentry->d_parent->d_inode;
305
306 /* This is the xattr dir, handle specially. */
307 if (S_ISDIR(dentry->d_inode->i_mode))
308 return xattr_rmdir(dir, dentry);
309
310 return xattr_unlink(dir, dentry);
311}
312
313static int chown_one_xattr(struct dentry *dentry, void *data)
314{
315 struct iattr *attrs = data;
316 return reiserfs_setattr(dentry, attrs);
317}
318
319/* No i_mutex, but the inode is unconnected. */
320int reiserfs_delete_xattrs(struct inode *inode)
321{
322 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
323 if (err)
324 reiserfs_warning(inode->i_sb, "jdm-20004",
325 "Couldn't delete all xattrs (%d)\n", err);
326 return err;
327}
328
329/* inode->i_mutex: down */
330int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
331{
332 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400333 if (err)
334 reiserfs_warning(inode->i_sb, "jdm-20007",
335 "Couldn't chown all xattrs (%d)\n", err);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400336 return err;
337}
338
339#ifdef CONFIG_REISERFS_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340/* Returns a dentry corresponding to a specific extended attribute file
341 * for the inode. If flags allow, the file is created. Otherwise, a
342 * valid or negative dentry, or an error is returned. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400343static struct dentry *xattr_lookup(struct inode *inode, const char *name,
344 int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700346 struct dentry *xadir, *xafile;
347 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700349 xadir = open_xa_dir(inode, flags);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400350 if (IS_ERR(xadir))
David Howellse231c2e2008-02-07 00:15:26 -0800351 return ERR_CAST(xadir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400353 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700354 xafile = lookup_one_len(name, xadir, strlen(name));
355 if (IS_ERR(xafile)) {
Jeff Mahoney6c176752009-03-30 14:02:34 -0400356 err = PTR_ERR(xafile);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700357 goto out;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400358 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
Jeff Mahoney6c176752009-03-30 14:02:34 -0400360 if (xafile->d_inode && (flags & XATTR_CREATE))
361 err = -EEXIST;
362
363 if (!xafile->d_inode) {
364 err = -ENODATA;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400365 if (xattr_may_create(flags))
Jeff Mahoney6c176752009-03-30 14:02:34 -0400366 err = xattr_create(xadir->d_inode, xafile,
367 0700|S_IFREG);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700368 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
Jeff Mahoney6c176752009-03-30 14:02:34 -0400370 if (err)
371 dput(xafile);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400372out:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400373 mutex_unlock(&xadir->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700374 dput(xadir);
375 if (err)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400376 return ERR_PTR(err);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800377 return xafile;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378}
379
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380/* Internal operations on file data */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700381static inline void reiserfs_put_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700383 kunmap(page);
384 page_cache_release(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385}
386
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400387static struct page *reiserfs_get_page(struct inode *dir, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700389 struct address_space *mapping = dir->i_mapping;
390 struct page *page;
391 /* We can deadlock if we try to free dentries,
392 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
Al Viroc4cdd032005-10-21 03:22:39 -0400393 mapping_set_gfp_mask(mapping, GFP_NOFS);
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400394 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700395 if (!IS_ERR(page)) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700396 kmap(page);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700397 if (PageError(page))
398 goto fail;
399 }
400 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700402 fail:
403 reiserfs_put_page(page);
404 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405}
406
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700407static inline __u32 xattr_hash(const char *msg, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700409 return csum_partial(msg, len, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410}
411
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700412int reiserfs_commit_write(struct file *f, struct page *page,
413 unsigned from, unsigned to);
414int reiserfs_prepare_write(struct file *f, struct page *page,
415 unsigned from, unsigned to);
416
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400417static void update_ctime(struct inode *inode)
418{
419 struct timespec now = current_fs_time(inode->i_sb);
420 if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink ||
421 timespec_equal(&inode->i_ctime, &now))
422 return;
423
424 inode->i_ctime = CURRENT_TIME_SEC;
425 mark_inode_dirty(inode);
426}
427
428static int lookup_and_delete_xattr(struct inode *inode, const char *name)
429{
430 int err = 0;
431 struct dentry *dentry, *xadir;
432
433 xadir = open_xa_dir(inode, XATTR_REPLACE);
434 if (IS_ERR(xadir))
435 return PTR_ERR(xadir);
436
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400437 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400438 dentry = lookup_one_len(name, xadir, strlen(name));
439 if (IS_ERR(dentry)) {
440 err = PTR_ERR(dentry);
441 goto out_dput;
442 }
443
444 if (dentry->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400445 err = xattr_unlink(xadir->d_inode, dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400446 update_ctime(inode);
447 }
448
449 dput(dentry);
450out_dput:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400451 mutex_unlock(&xadir->d_inode->i_mutex);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400452 dput(xadir);
453 return err;
454}
455
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700456
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457/* Generic extended attribute operations that can be used by xa plugins */
458
459/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800460 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 */
462int
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400463reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
464 struct inode *inode, const char *name,
465 const void *buffer, size_t buffer_size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700467 int err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800468 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700469 struct page *page;
470 char *data;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700471 size_t file_pos = 0;
472 size_t buffer_pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400473 size_t new_size;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700474 __u32 xahash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700476 if (get_inode_sd_version(inode) == STAT_DATA_V1)
477 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400479 if (!buffer)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400480 return lookup_and_delete_xattr(inode, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400482 dentry = xattr_lookup(inode, name, flags);
483 if (IS_ERR(dentry))
484 return PTR_ERR(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400486 down_write(&REISERFS_I(inode)->i_xattr_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400488 xahash = xattr_hash(buffer, buffer_size);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700489 while (buffer_pos < buffer_size || buffer_pos == 0) {
490 size_t chunk;
491 size_t skip = 0;
492 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
493 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
494 chunk = PAGE_CACHE_SIZE;
495 else
496 chunk = buffer_size - buffer_pos;
497
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400498 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700499 if (IS_ERR(page)) {
500 err = PTR_ERR(page);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400501 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700502 }
503
504 lock_page(page);
505 data = page_address(page);
506
507 if (file_pos == 0) {
508 struct reiserfs_xattr_header *rxh;
509 skip = file_pos = sizeof(struct reiserfs_xattr_header);
510 if (chunk + skip > PAGE_CACHE_SIZE)
511 chunk = PAGE_CACHE_SIZE - skip;
512 rxh = (struct reiserfs_xattr_header *)data;
513 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
514 rxh->h_hash = cpu_to_le32(xahash);
515 }
516
Jeff Mahoney3227e142008-02-15 14:37:22 -0800517 err = reiserfs_prepare_write(NULL, page, page_offset,
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700518 page_offset + chunk + skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700519 if (!err) {
520 if (buffer)
521 memcpy(data + skip, buffer + buffer_pos, chunk);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800522 err = reiserfs_commit_write(NULL, page, page_offset,
523 page_offset + chunk +
524 skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700525 }
526 unlock_page(page);
527 reiserfs_put_page(page);
528 buffer_pos += chunk;
529 file_pos += chunk;
530 skip = 0;
531 if (err || buffer_size == 0 || !buffer)
532 break;
533 }
534
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400535 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
536 if (!err && new_size < i_size_read(dentry->d_inode)) {
537 struct iattr newattrs = {
538 .ia_ctime = current_fs_time(inode->i_sb),
539 .ia_size = buffer_size,
540 .ia_valid = ATTR_SIZE | ATTR_CTIME,
541 };
542 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
543 down_write(&dentry->d_inode->i_alloc_sem);
544 err = reiserfs_setattr(dentry, &newattrs);
545 up_write(&dentry->d_inode->i_alloc_sem);
546 mutex_unlock(&dentry->d_inode->i_mutex);
547 } else
548 update_ctime(inode);
549out_unlock:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400550 up_write(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800551 dput(dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400552 return err;
553}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700554
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400555/* We need to start a transaction to maintain lock ordering */
556int reiserfs_xattr_set(struct inode *inode, const char *name,
557 const void *buffer, size_t buffer_size, int flags)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400558{
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400559
560 struct reiserfs_transaction_handle th;
561 int error, error2;
562 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
563
564 if (!(flags & XATTR_REPLACE))
565 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
566
567 reiserfs_write_lock(inode->i_sb);
568 error = journal_begin(&th, inode->i_sb, jbegin_count);
569 if (error) {
570 reiserfs_write_unlock(inode->i_sb);
571 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700572 }
573
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400574 error = reiserfs_xattr_set_handle(&th, inode, name,
575 buffer, buffer_size, flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700576
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400577 error2 = journal_end(&th, inode->i_sb, jbegin_count);
578 if (error == 0)
579 error = error2;
580 reiserfs_write_unlock(inode->i_sb);
581
582 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583}
584
585/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800586 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 */
588int
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400589reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700590 size_t buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700592 ssize_t err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800593 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700594 size_t isize;
595 size_t file_pos = 0;
596 size_t buffer_pos = 0;
597 struct page *page;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700598 __u32 hash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700600 if (name == NULL)
601 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700603 /* We can't have xattrs attached to v1 items since they don't have
604 * generation numbers */
605 if (get_inode_sd_version(inode) == STAT_DATA_V1)
606 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400608 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800609 if (IS_ERR(dentry)) {
610 err = PTR_ERR(dentry);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700611 goto out;
612 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400614 down_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoneyd9845612009-03-30 14:02:35 -0400615
Jeff Mahoneyf437c522009-03-30 14:02:29 -0400616 isize = i_size_read(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700618 /* Just return the size needed */
619 if (buffer == NULL) {
620 err = isize - sizeof(struct reiserfs_xattr_header);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400621 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700622 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700624 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
625 err = -ERANGE;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400626 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700627 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700629 while (file_pos < isize) {
630 size_t chunk;
631 char *data;
632 size_t skip = 0;
633 if (isize - file_pos > PAGE_CACHE_SIZE)
634 chunk = PAGE_CACHE_SIZE;
635 else
636 chunk = isize - file_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400638 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700639 if (IS_ERR(page)) {
640 err = PTR_ERR(page);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400641 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700642 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700644 lock_page(page);
645 data = page_address(page);
646 if (file_pos == 0) {
647 struct reiserfs_xattr_header *rxh =
648 (struct reiserfs_xattr_header *)data;
649 skip = file_pos = sizeof(struct reiserfs_xattr_header);
650 chunk -= skip;
651 /* Magic doesn't match up.. */
652 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
653 unlock_page(page);
654 reiserfs_put_page(page);
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400655 reiserfs_warning(inode->i_sb, "jdm-20001",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700656 "Invalid magic for xattr (%s) "
657 "associated with %k", name,
658 INODE_PKEY(inode));
659 err = -EIO;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400660 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700661 }
662 hash = le32_to_cpu(rxh->h_hash);
663 }
664 memcpy(buffer + buffer_pos, data + skip, chunk);
665 unlock_page(page);
666 reiserfs_put_page(page);
667 file_pos += chunk;
668 buffer_pos += chunk;
669 skip = 0;
670 }
671 err = isize - sizeof(struct reiserfs_xattr_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700673 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
674 hash) {
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400675 reiserfs_warning(inode->i_sb, "jdm-20002",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700676 "Invalid hash for xattr (%s) associated "
677 "with %k", name, INODE_PKEY(inode));
678 err = -EIO;
679 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400681out_unlock:
682 up_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800683 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400685out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700686 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687}
688
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400689/*
690 * In order to implement different sets of xattr operations for each xattr
691 * prefix with the generic xattr API, a filesystem should create a
692 * null-terminated array of struct xattr_handler (one for each prefix) and
693 * hang a pointer to it off of the s_xattr field of the superblock.
694 *
695 * The generic_fooxattr() functions will use this list to dispatch xattr
696 * operations to the correct xattr_handler.
697 */
698#define for_each_xattr_handler(handlers, handler) \
699 for ((handler) = *(handlers)++; \
700 (handler) != NULL; \
701 (handler) = *(handlers)++)
702
703/* This is the implementation for the xattr plugin infrastructure */
704static inline struct xattr_handler *
705find_xattr_handler_prefix(struct xattr_handler **handlers,
706 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400708 struct xattr_handler *xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400710 if (!handlers)
711 return NULL;
712
713 for_each_xattr_handler(handlers, xah) {
714 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
715 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 }
717
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400718 return xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719}
720
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721
722/*
723 * Inode operation getxattr()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 */
725ssize_t
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700726reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
727 size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400729 struct inode *inode = dentry->d_inode;
730 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400732 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
733
734 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700735 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400737 return handler->get(inode, name, buffer, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738}
739
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740/*
741 * Inode operation setxattr()
742 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800743 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 */
745int
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700746reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
747 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400749 struct inode *inode = dentry->d_inode;
750 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400752 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
753
754 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700755 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400757 return handler->set(inode, name, value, size, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758}
759
760/*
761 * Inode operation removexattr()
762 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800763 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700765int reiserfs_removexattr(struct dentry *dentry, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400767 struct inode *inode = dentry->d_inode;
768 struct xattr_handler *handler;
769 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400771 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700772 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400774 return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775}
776
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400777struct listxattr_buf {
778 size_t size;
779 size_t pos;
780 char *buf;
781 struct inode *inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782};
783
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400784static int listxattr_filler(void *buf, const char *name, int namelen,
785 loff_t offset, u64 ino, unsigned int d_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400787 struct listxattr_buf *b = (struct listxattr_buf *)buf;
788 size_t size;
789 if (name[0] != '.' ||
790 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
791 struct xattr_handler *handler;
792 handler = find_xattr_handler_prefix(b->inode->i_sb->s_xattr,
793 name);
794 if (!handler) /* Unsupported xattr name */
795 return 0;
796 if (b->buf) {
797 size = handler->list(b->inode, b->buf + b->pos,
798 b->size, name, namelen);
799 if (size > b->size)
800 return -ERANGE;
801 } else {
802 size = handler->list(b->inode, NULL, 0, name, namelen);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700803 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400805 b->pos += size;
806 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700807 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700809
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810/*
811 * Inode operation listxattr()
812 *
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400813 * We totally ignore the generic listxattr here because it would be stupid
814 * not to. Since the xattrs are organized in a directory, we can just
815 * readdir to find them.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700817ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700819 struct dentry *dir;
820 int err = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400821 loff_t pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400822 struct listxattr_buf buf = {
823 .inode = dentry->d_inode,
824 .buf = buffer,
825 .size = buffer ? size : 0,
826 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700828 if (!dentry->d_inode)
829 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830
Jeff Mahoney677c9b22009-05-05 15:30:17 -0400831 if (!dentry->d_sb->s_xattr ||
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700832 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
833 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834
Jeff Mahoney6c176752009-03-30 14:02:34 -0400835 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700836 if (IS_ERR(dir)) {
837 err = PTR_ERR(dir);
838 if (err == -ENODATA)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400839 err = 0; /* Not an error if there aren't any xattrs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700840 goto out;
841 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842
Jeff Mahoney6c176752009-03-30 14:02:34 -0400843 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400844 err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400845 mutex_unlock(&dir->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400847 if (!err)
848 err = buf.pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
Jeff Mahoney3227e142008-02-15 14:37:22 -0800850 dput(dir);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400851out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700852 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853}
854
Christoph Hellwigec191572006-02-01 03:06:46 -0800855static int reiserfs_check_acl(struct inode *inode, int mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856{
Christoph Hellwigec191572006-02-01 03:06:46 -0800857 struct posix_acl *acl;
858 int error = -EAGAIN; /* do regular unix permission checks by default */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700859
Christoph Hellwigec191572006-02-01 03:06:46 -0800860 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
861
Christoph Hellwigec191572006-02-01 03:06:46 -0800862 if (acl) {
863 if (!IS_ERR(acl)) {
864 error = posix_acl_permission(inode, acl, mask);
865 posix_acl_release(acl);
866 } else if (PTR_ERR(acl) != -ENODATA)
867 error = PTR_ERR(acl);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700868 }
869
Christoph Hellwigec191572006-02-01 03:06:46 -0800870 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700871}
872
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400873static int create_privroot(struct dentry *dentry)
874{
875 int err;
876 struct inode *inode = dentry->d_parent->d_inode;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400877 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
878
Jeff Mahoney6c176752009-03-30 14:02:34 -0400879 err = xattr_mkdir(inode, dentry, 0700);
Al Viroedcc37a2009-05-03 06:00:05 -0400880 if (err || !dentry->d_inode) {
881 reiserfs_warning(dentry->d_sb, "jdm-20006",
882 "xattrs/ACLs enabled and couldn't "
883 "find/create .reiserfs_priv. "
884 "Failing mount.");
885 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700886 }
887
Al Viroedcc37a2009-05-03 06:00:05 -0400888 dentry->d_inode->i_flags |= S_PRIVATE;
889 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
890 "storage.\n", PRIVROOT_NAME);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700891
Al Viroedcc37a2009-05-03 06:00:05 -0400892 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400893}
894
Jeff Mahoney12abb352009-05-17 01:02:01 -0400895#else
896int __init reiserfs_xattr_register_handlers(void) { return 0; }
897void reiserfs_xattr_unregister_handlers(void) {}
898static int create_privroot(struct dentry *dentry) { return 0; }
899#endif
900
901/* Actual operations that are exported to VFS-land */
902struct xattr_handler *reiserfs_xattr_handlers[] = {
903#ifdef CONFIG_REISERFS_FS_XATTR
904 &reiserfs_xattr_user_handler,
905 &reiserfs_xattr_trusted_handler,
906#endif
907#ifdef CONFIG_REISERFS_FS_SECURITY
908 &reiserfs_xattr_security_handler,
909#endif
910#ifdef CONFIG_REISERFS_FS_POSIX_ACL
911 &reiserfs_posix_acl_access_handler,
912 &reiserfs_posix_acl_default_handler,
913#endif
914 NULL
915};
916
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400917static int xattr_mount_check(struct super_block *s)
918{
919 /* We need generation numbers to ensure that the oid mapping is correct
920 * v3.5 filesystems don't have them. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400921 if (old_format_only(s)) {
922 if (reiserfs_xattrs_optional(s)) {
923 /* Old format filesystem, but optional xattrs have
924 * been enabled. Error out. */
925 reiserfs_warning(s, "jdm-2005",
926 "xattrs/ACLs not supported "
927 "on pre-v3.6 format filesystems. "
928 "Failing mount.");
929 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700930 }
931 }
932
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400933 return 0;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700934}
935
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400936int reiserfs_permission(struct inode *inode, int mask)
937{
938 /*
939 * We don't do permission checks on the internal objects.
940 * Permissions are determined by the "owning" object.
941 */
942 if (IS_PRIVATE(inode))
943 return 0;
944
945#ifdef CONFIG_REISERFS_FS_XATTR
946 /*
947 * Stat data v1 doesn't support ACLs.
948 */
949 if (get_inode_sd_version(inode) != STAT_DATA_V1)
950 return generic_permission(inode, mask, reiserfs_check_acl);
951#endif
952 return generic_permission(inode, mask, NULL);
953}
954
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955/* This will catch lookups from the fs root to .reiserfs_priv */
956static int
957xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
958{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700959 struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
Al Viroedcc37a2009-05-03 06:00:05 -0400960 if (container_of(q1, struct dentry, d_name) == priv_root)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700961 return -ENOENT;
Al Viroedcc37a2009-05-03 06:00:05 -0400962 if (q1->len == name->len &&
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700963 !memcmp(q1->name, name->name, name->len))
964 return 0;
965 return 1;
966}
967
Al Viroe16404e2009-02-20 05:55:13 +0000968static const struct dentry_operations xattr_lookup_poison_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 .d_compare = xattr_lookup_poison,
970};
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700971
Al Viroedcc37a2009-05-03 06:00:05 -0400972int reiserfs_lookup_privroot(struct super_block *s)
973{
974 struct dentry *dentry;
975 int err = 0;
976
977 /* If we don't have the privroot located yet - go find it */
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +0200978 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -0400979 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
980 strlen(PRIVROOT_NAME));
981 if (!IS_ERR(dentry)) {
982 REISERFS_SB(s)->priv_root = dentry;
Jeff Mahoney73422812009-05-10 16:05:39 -0400983 if (!reiserfs_expose_privroot(s))
984 s->s_root->d_op = &xattr_lookup_poison_ops;
Al Viroedcc37a2009-05-03 06:00:05 -0400985 if (dentry->d_inode)
986 dentry->d_inode->i_flags |= S_PRIVATE;
987 } else
988 err = PTR_ERR(dentry);
989 mutex_unlock(&s->s_root->d_inode->i_mutex);
990
991 return err;
992}
993
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994/* We need to take a copy of the mount flags since things like
995 * MS_RDONLY don't get set until *after* we're called.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 * mount_flags != mount_options */
997int reiserfs_xattr_init(struct super_block *s, int mount_flags)
998{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700999 int err = 0;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001000 struct dentry *privroot = REISERFS_SB(s)->priv_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001002 err = xattr_mount_check(s);
1003 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001004 goto error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001005
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001006 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
Frederic Weisbeckerae635c02009-08-25 02:24:45 +02001007 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -04001008 err = create_privroot(REISERFS_SB(s)->priv_root);
Jeff Mahoney5a6059c2009-05-01 12:11:12 -04001009 mutex_unlock(&s->s_root->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001010 }
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001011
1012 if (privroot->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001013 s->s_xattr = reiserfs_xattr_handlers;
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +02001014 reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001015 if (!REISERFS_SB(s)->xattr_root) {
1016 struct dentry *dentry;
1017 dentry = lookup_one_len(XAROOT_NAME, privroot,
1018 strlen(XAROOT_NAME));
1019 if (!IS_ERR(dentry))
1020 REISERFS_SB(s)->xattr_root = dentry;
1021 else
1022 err = PTR_ERR(dentry);
1023 }
1024 mutex_unlock(&privroot->d_inode->i_mutex);
1025 }
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001026
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001027error:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001028 if (err) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001029 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1030 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1031 }
1032
1033 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001034 if (reiserfs_posixacl(s))
1035 s->s_flags |= MS_POSIXACL;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001036 else
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001037 s->s_flags &= ~MS_POSIXACL;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001038
1039 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040}