blob: 8c4cf273c672185fe7cb4c5d0a6e30ddc85e5bf3 [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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090041#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/fs.h>
43#include <linux/file.h>
44#include <linux/pagemap.h>
45#include <linux/xattr.h>
46#include <linux/reiserfs_xattr.h>
47#include <linux/reiserfs_acl.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <asm/uaccess.h>
Al Viro3277c392006-11-14 21:13:53 -080049#include <net/checksum.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <linux/stat.h>
Jeff Mahoney6c176752009-03-30 14:02:34 -040051#include <linux/quotaops.h>
Christoph Hellwig431547b2009-11-13 09:52:56 +000052#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
Linus Torvalds1da177e2005-04-16 15:20:36 -070054#define PRIVROOT_NAME ".reiserfs_priv"
55#define XAROOT_NAME "xattrs"
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Jeff Mahoney6c176752009-03-30 14:02:34 -040058/* Helpers for inode ops. We do this so that we don't have all the VFS
59 * overhead and also for proper i_mutex annotation.
60 * dir->i_mutex must be held for all of them. */
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040061#ifdef CONFIG_REISERFS_FS_XATTR
Jeff Mahoney6c176752009-03-30 14:02:34 -040062static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
Jeff Mahoney6c176752009-03-30 14:02:34 -040064 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Jeff Mahoney6c176752009-03-30 14:02:34 -040065 return dir->i_op->create(dir, dentry, mode, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070066}
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040067#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Jeff Mahoney6c176752009-03-30 14:02:34 -040069static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode)
70{
71 BUG_ON(!mutex_is_locked(&dir->i_mutex));
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));
Jeff Mahoney6c176752009-03-30 14:02:34 -040083
Frederic Weisbecker4dd85962009-12-30 07:26:28 +010084 reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
85 I_MUTEX_CHILD, dir->i_sb);
Jeff Mahoney6c176752009-03-30 14:02:34 -040086 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));
Jeff Mahoney6c176752009-03-30 14:02:34 -040098
Frederic Weisbecker835d5242009-12-30 07:40:39 +010099 reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
100 I_MUTEX_CHILD, dir->i_sb);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400101 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
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100237 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400238 dir = open_xa_dir(inode, XATTR_REPLACE);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400239 if (IS_ERR(dir)) {
240 err = PTR_ERR(dir);
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100241 reiserfs_write_lock(inode->i_sb);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400242 goto out;
243 } else if (!dir->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400244 err = 0;
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100245 reiserfs_write_lock(inode->i_sb);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400246 goto out_dir;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400247 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400248
Jeff Mahoney6c176752009-03-30 14:02:34 -0400249 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100250
251 reiserfs_write_lock(inode->i_sb);
252
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400253 buf.xadir = dir;
254 err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
255 while ((err == 0 || err == -ENOSPC) && buf.count) {
256 err = 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400257
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400258 for (i = 0; i < buf.count && buf.dentries[i]; i++) {
259 int lerr = 0;
260 struct dentry *dentry = buf.dentries[i];
261
262 if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
263 lerr = action(dentry, data);
264
265 dput(dentry);
266 buf.dentries[i] = NULL;
267 err = lerr ?: err;
268 }
269 buf.count = 0;
270 if (!err)
271 err = reiserfs_readdir_dentry(dir, &buf,
272 fill_with_dentries, &pos);
273 }
Jeff Mahoney6c176752009-03-30 14:02:34 -0400274 mutex_unlock(&dir->d_inode->i_mutex);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400275
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400276 /* Clean up after a failed readdir */
277 cleanup_dentry_buf(&buf);
278
279 if (!err) {
280 /* We start a transaction here to avoid a ABBA situation
281 * between the xattr root's i_mutex and the journal lock.
282 * This doesn't incur much additional overhead since the
283 * new transaction will just nest inside the
284 * outer transaction. */
285 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
286 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
287 struct reiserfs_transaction_handle th;
288 err = journal_begin(&th, inode->i_sb, blocks);
289 if (!err) {
290 int jerror;
Frederic Weisbecker8b513f52009-12-30 07:28:58 +0100291 reiserfs_mutex_lock_nested_safe(
292 &dir->d_parent->d_inode->i_mutex,
293 I_MUTEX_XATTR, inode->i_sb);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400294 err = action(dir, data);
295 jerror = journal_end(&th, inode->i_sb, blocks);
296 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
297 err = jerror ?: err;
298 }
299 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400300out_dir:
301 dput(dir);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400302out:
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400303 /* -ENODATA isn't an error */
304 if (err == -ENODATA)
305 err = 0;
306 return err;
307}
308
309static int delete_one_xattr(struct dentry *dentry, void *data)
310{
311 struct inode *dir = dentry->d_parent->d_inode;
312
313 /* This is the xattr dir, handle specially. */
314 if (S_ISDIR(dentry->d_inode->i_mode))
315 return xattr_rmdir(dir, dentry);
316
317 return xattr_unlink(dir, dentry);
318}
319
320static int chown_one_xattr(struct dentry *dentry, void *data)
321{
322 struct iattr *attrs = data;
323 return reiserfs_setattr(dentry, attrs);
324}
325
326/* No i_mutex, but the inode is unconnected. */
327int reiserfs_delete_xattrs(struct inode *inode)
328{
329 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
330 if (err)
331 reiserfs_warning(inode->i_sb, "jdm-20004",
332 "Couldn't delete all xattrs (%d)\n", err);
333 return err;
334}
335
336/* inode->i_mutex: down */
337int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
338{
339 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400340 if (err)
341 reiserfs_warning(inode->i_sb, "jdm-20007",
342 "Couldn't chown all xattrs (%d)\n", err);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400343 return err;
344}
345
346#ifdef CONFIG_REISERFS_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347/* Returns a dentry corresponding to a specific extended attribute file
348 * for the inode. If flags allow, the file is created. Otherwise, a
349 * valid or negative dentry, or an error is returned. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400350static struct dentry *xattr_lookup(struct inode *inode, const char *name,
351 int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700353 struct dentry *xadir, *xafile;
354 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700356 xadir = open_xa_dir(inode, flags);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400357 if (IS_ERR(xadir))
David Howellse231c2e2008-02-07 00:15:26 -0800358 return ERR_CAST(xadir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400360 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700361 xafile = lookup_one_len(name, xadir, strlen(name));
362 if (IS_ERR(xafile)) {
Jeff Mahoney6c176752009-03-30 14:02:34 -0400363 err = PTR_ERR(xafile);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700364 goto out;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400365 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
Jeff Mahoney6c176752009-03-30 14:02:34 -0400367 if (xafile->d_inode && (flags & XATTR_CREATE))
368 err = -EEXIST;
369
370 if (!xafile->d_inode) {
371 err = -ENODATA;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400372 if (xattr_may_create(flags))
Jeff Mahoney6c176752009-03-30 14:02:34 -0400373 err = xattr_create(xadir->d_inode, xafile,
374 0700|S_IFREG);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700375 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
Jeff Mahoney6c176752009-03-30 14:02:34 -0400377 if (err)
378 dput(xafile);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400379out:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400380 mutex_unlock(&xadir->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700381 dput(xadir);
382 if (err)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400383 return ERR_PTR(err);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800384 return xafile;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385}
386
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387/* Internal operations on file data */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700388static inline void reiserfs_put_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700390 kunmap(page);
391 page_cache_release(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392}
393
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400394static struct page *reiserfs_get_page(struct inode *dir, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700396 struct address_space *mapping = dir->i_mapping;
397 struct page *page;
398 /* We can deadlock if we try to free dentries,
399 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
Al Viroc4cdd032005-10-21 03:22:39 -0400400 mapping_set_gfp_mask(mapping, GFP_NOFS);
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400401 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700402 if (!IS_ERR(page)) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700403 kmap(page);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700404 if (PageError(page))
405 goto fail;
406 }
407 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700409 fail:
410 reiserfs_put_page(page);
411 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412}
413
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700414static inline __u32 xattr_hash(const char *msg, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700416 return csum_partial(msg, len, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417}
418
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700419int reiserfs_commit_write(struct file *f, struct page *page,
420 unsigned from, unsigned to);
421int reiserfs_prepare_write(struct file *f, struct page *page,
422 unsigned from, unsigned to);
423
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400424static void update_ctime(struct inode *inode)
425{
426 struct timespec now = current_fs_time(inode->i_sb);
427 if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink ||
428 timespec_equal(&inode->i_ctime, &now))
429 return;
430
431 inode->i_ctime = CURRENT_TIME_SEC;
432 mark_inode_dirty(inode);
433}
434
435static int lookup_and_delete_xattr(struct inode *inode, const char *name)
436{
437 int err = 0;
438 struct dentry *dentry, *xadir;
439
440 xadir = open_xa_dir(inode, XATTR_REPLACE);
441 if (IS_ERR(xadir))
442 return PTR_ERR(xadir);
443
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400444 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400445 dentry = lookup_one_len(name, xadir, strlen(name));
446 if (IS_ERR(dentry)) {
447 err = PTR_ERR(dentry);
448 goto out_dput;
449 }
450
451 if (dentry->d_inode) {
Frederic Weisbecker4f3be1b2010-01-05 02:14:30 +0100452 reiserfs_write_lock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400453 err = xattr_unlink(xadir->d_inode, dentry);
Frederic Weisbecker4f3be1b2010-01-05 02:14:30 +0100454 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400455 update_ctime(inode);
456 }
457
458 dput(dentry);
459out_dput:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400460 mutex_unlock(&xadir->d_inode->i_mutex);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400461 dput(xadir);
462 return err;
463}
464
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466/* Generic extended attribute operations that can be used by xa plugins */
467
468/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800469 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 */
471int
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400472reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
473 struct inode *inode, const char *name,
474 const void *buffer, size_t buffer_size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700476 int err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800477 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700478 struct page *page;
479 char *data;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700480 size_t file_pos = 0;
481 size_t buffer_pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400482 size_t new_size;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700483 __u32 xahash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700485 if (get_inode_sd_version(inode) == STAT_DATA_V1)
486 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100488 reiserfs_write_unlock(inode->i_sb);
Frederic Weisbecker4f3be1b2010-01-05 02:14:30 +0100489
490 if (!buffer) {
491 err = lookup_and_delete_xattr(inode, name);
492 reiserfs_write_lock(inode->i_sb);
493 return err;
494 }
495
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400496 dentry = xattr_lookup(inode, name, flags);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100497 if (IS_ERR(dentry)) {
498 reiserfs_write_lock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400499 return PTR_ERR(dentry);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100500 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501
Frederic Weisbeckerf3e22f42010-01-03 03:44:53 +0100502 down_write(&REISERFS_I(inode)->i_xattr_sem);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100503
504 reiserfs_write_lock(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400506 xahash = xattr_hash(buffer, buffer_size);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700507 while (buffer_pos < buffer_size || buffer_pos == 0) {
508 size_t chunk;
509 size_t skip = 0;
510 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
511 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
512 chunk = PAGE_CACHE_SIZE;
513 else
514 chunk = buffer_size - buffer_pos;
515
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400516 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700517 if (IS_ERR(page)) {
518 err = PTR_ERR(page);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400519 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700520 }
521
522 lock_page(page);
523 data = page_address(page);
524
525 if (file_pos == 0) {
526 struct reiserfs_xattr_header *rxh;
527 skip = file_pos = sizeof(struct reiserfs_xattr_header);
528 if (chunk + skip > PAGE_CACHE_SIZE)
529 chunk = PAGE_CACHE_SIZE - skip;
530 rxh = (struct reiserfs_xattr_header *)data;
531 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
532 rxh->h_hash = cpu_to_le32(xahash);
533 }
534
Jeff Mahoney3227e142008-02-15 14:37:22 -0800535 err = reiserfs_prepare_write(NULL, page, page_offset,
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700536 page_offset + chunk + skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700537 if (!err) {
538 if (buffer)
539 memcpy(data + skip, buffer + buffer_pos, chunk);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800540 err = reiserfs_commit_write(NULL, page, page_offset,
541 page_offset + chunk +
542 skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700543 }
544 unlock_page(page);
545 reiserfs_put_page(page);
546 buffer_pos += chunk;
547 file_pos += chunk;
548 skip = 0;
549 if (err || buffer_size == 0 || !buffer)
550 break;
551 }
552
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400553 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
554 if (!err && new_size < i_size_read(dentry->d_inode)) {
555 struct iattr newattrs = {
556 .ia_ctime = current_fs_time(inode->i_sb),
Jeff Mahoneyfb2162d2010-04-23 13:17:41 -0400557 .ia_size = new_size,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400558 .ia_valid = ATTR_SIZE | ATTR_CTIME,
559 };
Frederic Weisbecker31370f62010-01-07 15:55:31 +0100560
561 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400562 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
563 down_write(&dentry->d_inode->i_alloc_sem);
Frederic Weisbecker31370f62010-01-07 15:55:31 +0100564 reiserfs_write_lock(inode->i_sb);
565
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400566 err = reiserfs_setattr(dentry, &newattrs);
567 up_write(&dentry->d_inode->i_alloc_sem);
568 mutex_unlock(&dentry->d_inode->i_mutex);
569 } else
570 update_ctime(inode);
571out_unlock:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400572 up_write(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800573 dput(dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400574 return err;
575}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700576
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400577/* We need to start a transaction to maintain lock ordering */
578int reiserfs_xattr_set(struct inode *inode, const char *name,
579 const void *buffer, size_t buffer_size, int flags)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400580{
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400581
582 struct reiserfs_transaction_handle th;
583 int error, error2;
584 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
585
586 if (!(flags & XATTR_REPLACE))
587 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
588
589 reiserfs_write_lock(inode->i_sb);
590 error = journal_begin(&th, inode->i_sb, jbegin_count);
591 if (error) {
592 reiserfs_write_unlock(inode->i_sb);
593 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700594 }
595
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400596 error = reiserfs_xattr_set_handle(&th, inode, name,
597 buffer, buffer_size, flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700598
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400599 error2 = journal_end(&th, inode->i_sb, jbegin_count);
600 if (error == 0)
601 error = error2;
602 reiserfs_write_unlock(inode->i_sb);
603
604 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605}
606
607/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800608 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 */
610int
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400611reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700612 size_t buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700614 ssize_t err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800615 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700616 size_t isize;
617 size_t file_pos = 0;
618 size_t buffer_pos = 0;
619 struct page *page;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700620 __u32 hash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700622 if (name == NULL)
623 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700625 /* We can't have xattrs attached to v1 items since they don't have
626 * generation numbers */
627 if (get_inode_sd_version(inode) == STAT_DATA_V1)
628 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400630 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800631 if (IS_ERR(dentry)) {
632 err = PTR_ERR(dentry);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700633 goto out;
634 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400636 down_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoneyd9845612009-03-30 14:02:35 -0400637
Jeff Mahoneyf437c522009-03-30 14:02:29 -0400638 isize = i_size_read(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700640 /* Just return the size needed */
641 if (buffer == NULL) {
642 err = isize - sizeof(struct reiserfs_xattr_header);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400643 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700644 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700646 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
647 err = -ERANGE;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400648 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700649 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700651 while (file_pos < isize) {
652 size_t chunk;
653 char *data;
654 size_t skip = 0;
655 if (isize - file_pos > PAGE_CACHE_SIZE)
656 chunk = PAGE_CACHE_SIZE;
657 else
658 chunk = isize - file_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400660 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700661 if (IS_ERR(page)) {
662 err = PTR_ERR(page);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400663 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700664 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700666 lock_page(page);
667 data = page_address(page);
668 if (file_pos == 0) {
669 struct reiserfs_xattr_header *rxh =
670 (struct reiserfs_xattr_header *)data;
671 skip = file_pos = sizeof(struct reiserfs_xattr_header);
672 chunk -= skip;
673 /* Magic doesn't match up.. */
674 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
675 unlock_page(page);
676 reiserfs_put_page(page);
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400677 reiserfs_warning(inode->i_sb, "jdm-20001",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700678 "Invalid magic for xattr (%s) "
679 "associated with %k", name,
680 INODE_PKEY(inode));
681 err = -EIO;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400682 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700683 }
684 hash = le32_to_cpu(rxh->h_hash);
685 }
686 memcpy(buffer + buffer_pos, data + skip, chunk);
687 unlock_page(page);
688 reiserfs_put_page(page);
689 file_pos += chunk;
690 buffer_pos += chunk;
691 skip = 0;
692 }
693 err = isize - sizeof(struct reiserfs_xattr_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700695 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
696 hash) {
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400697 reiserfs_warning(inode->i_sb, "jdm-20002",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700698 "Invalid hash for xattr (%s) associated "
699 "with %k", name, INODE_PKEY(inode));
700 err = -EIO;
701 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400703out_unlock:
704 up_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800705 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400707out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700708 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709}
710
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400711/*
712 * In order to implement different sets of xattr operations for each xattr
713 * prefix with the generic xattr API, a filesystem should create a
714 * null-terminated array of struct xattr_handler (one for each prefix) and
715 * hang a pointer to it off of the s_xattr field of the superblock.
716 *
717 * The generic_fooxattr() functions will use this list to dispatch xattr
718 * operations to the correct xattr_handler.
719 */
720#define for_each_xattr_handler(handlers, handler) \
721 for ((handler) = *(handlers)++; \
722 (handler) != NULL; \
723 (handler) = *(handlers)++)
724
725/* This is the implementation for the xattr plugin infrastructure */
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700726static inline const struct xattr_handler *
727find_xattr_handler_prefix(const struct xattr_handler **handlers,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400728 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700730 const struct xattr_handler *xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400732 if (!handlers)
733 return NULL;
734
735 for_each_xattr_handler(handlers, xah) {
736 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
737 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 }
739
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400740 return xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741}
742
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743
744/*
745 * Inode operation getxattr()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 */
747ssize_t
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700748reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
749 size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700751 const struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
Christoph Hellwig431547b2009-11-13 09:52:56 +0000753 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400754
Christoph Hellwig431547b2009-11-13 09:52:56 +0000755 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700756 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
Christoph Hellwig431547b2009-11-13 09:52:56 +0000758 return handler->get(dentry, name, buffer, size, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759}
760
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761/*
762 * Inode operation setxattr()
763 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800764 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 */
766int
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700767reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
768 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700770 const struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771
Christoph Hellwig431547b2009-11-13 09:52:56 +0000772 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400773
Christoph Hellwig431547b2009-11-13 09:52:56 +0000774 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700775 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776
Christoph Hellwig431547b2009-11-13 09:52:56 +0000777 return handler->set(dentry, name, value, size, flags, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778}
779
780/*
781 * Inode operation removexattr()
782 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800783 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700785int reiserfs_removexattr(struct dentry *dentry, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700787 const struct xattr_handler *handler;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000788 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
Christoph Hellwig431547b2009-11-13 09:52:56 +0000790 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700791 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792
Christoph Hellwig431547b2009-11-13 09:52:56 +0000793 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794}
795
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400796struct listxattr_buf {
797 size_t size;
798 size_t pos;
799 char *buf;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000800 struct dentry *dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801};
802
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400803static int listxattr_filler(void *buf, const char *name, int namelen,
804 loff_t offset, u64 ino, unsigned int d_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400806 struct listxattr_buf *b = (struct listxattr_buf *)buf;
807 size_t size;
808 if (name[0] != '.' ||
809 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700810 const struct xattr_handler *handler;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000811 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400812 name);
813 if (!handler) /* Unsupported xattr name */
814 return 0;
815 if (b->buf) {
Christoph Hellwig431547b2009-11-13 09:52:56 +0000816 size = handler->list(b->dentry, b->buf + b->pos,
817 b->size, name, namelen,
818 handler->flags);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400819 if (size > b->size)
820 return -ERANGE;
821 } else {
Christoph Hellwig431547b2009-11-13 09:52:56 +0000822 size = handler->list(b->dentry, NULL, 0, name,
823 namelen, handler->flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700824 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400826 b->pos += size;
827 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700828 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700830
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831/*
832 * Inode operation listxattr()
833 *
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400834 * We totally ignore the generic listxattr here because it would be stupid
835 * not to. Since the xattrs are organized in a directory, we can just
836 * readdir to find them.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700838ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700840 struct dentry *dir;
841 int err = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400842 loff_t pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400843 struct listxattr_buf buf = {
Christoph Hellwig431547b2009-11-13 09:52:56 +0000844 .dentry = dentry,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400845 .buf = buffer,
846 .size = buffer ? size : 0,
847 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700849 if (!dentry->d_inode)
850 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851
Jeff Mahoney677c9b22009-05-05 15:30:17 -0400852 if (!dentry->d_sb->s_xattr ||
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700853 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
854 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855
Jeff Mahoney6c176752009-03-30 14:02:34 -0400856 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700857 if (IS_ERR(dir)) {
858 err = PTR_ERR(dir);
859 if (err == -ENODATA)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400860 err = 0; /* Not an error if there aren't any xattrs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700861 goto out;
862 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863
Jeff Mahoney6c176752009-03-30 14:02:34 -0400864 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400865 err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400866 mutex_unlock(&dir->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400868 if (!err)
869 err = buf.pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870
Jeff Mahoney3227e142008-02-15 14:37:22 -0800871 dput(dir);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400872out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700873 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874}
875
Christoph Hellwigec191572006-02-01 03:06:46 -0800876static int reiserfs_check_acl(struct inode *inode, int mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877{
Christoph Hellwigec191572006-02-01 03:06:46 -0800878 struct posix_acl *acl;
879 int error = -EAGAIN; /* do regular unix permission checks by default */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700880
Christoph Hellwigec191572006-02-01 03:06:46 -0800881 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
882
Christoph Hellwigec191572006-02-01 03:06:46 -0800883 if (acl) {
884 if (!IS_ERR(acl)) {
885 error = posix_acl_permission(inode, acl, mask);
886 posix_acl_release(acl);
887 } else if (PTR_ERR(acl) != -ENODATA)
888 error = PTR_ERR(acl);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700889 }
890
Christoph Hellwigec191572006-02-01 03:06:46 -0800891 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700892}
893
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400894static int create_privroot(struct dentry *dentry)
895{
896 int err;
897 struct inode *inode = dentry->d_parent->d_inode;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400898 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
899
Jeff Mahoney6c176752009-03-30 14:02:34 -0400900 err = xattr_mkdir(inode, dentry, 0700);
Al Viroedcc37a2009-05-03 06:00:05 -0400901 if (err || !dentry->d_inode) {
902 reiserfs_warning(dentry->d_sb, "jdm-20006",
903 "xattrs/ACLs enabled and couldn't "
904 "find/create .reiserfs_priv. "
905 "Failing mount.");
906 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700907 }
908
Al Viroedcc37a2009-05-03 06:00:05 -0400909 dentry->d_inode->i_flags |= S_PRIVATE;
910 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
911 "storage.\n", PRIVROOT_NAME);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700912
Al Viroedcc37a2009-05-03 06:00:05 -0400913 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400914}
915
Jeff Mahoney12abb352009-05-17 01:02:01 -0400916#else
917int __init reiserfs_xattr_register_handlers(void) { return 0; }
918void reiserfs_xattr_unregister_handlers(void) {}
919static int create_privroot(struct dentry *dentry) { return 0; }
920#endif
921
922/* Actual operations that are exported to VFS-land */
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700923const struct xattr_handler *reiserfs_xattr_handlers[] = {
Jeff Mahoney12abb352009-05-17 01:02:01 -0400924#ifdef CONFIG_REISERFS_FS_XATTR
925 &reiserfs_xattr_user_handler,
926 &reiserfs_xattr_trusted_handler,
927#endif
928#ifdef CONFIG_REISERFS_FS_SECURITY
929 &reiserfs_xattr_security_handler,
930#endif
931#ifdef CONFIG_REISERFS_FS_POSIX_ACL
932 &reiserfs_posix_acl_access_handler,
933 &reiserfs_posix_acl_default_handler,
934#endif
935 NULL
936};
937
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400938static int xattr_mount_check(struct super_block *s)
939{
940 /* We need generation numbers to ensure that the oid mapping is correct
941 * v3.5 filesystems don't have them. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400942 if (old_format_only(s)) {
943 if (reiserfs_xattrs_optional(s)) {
944 /* Old format filesystem, but optional xattrs have
945 * been enabled. Error out. */
946 reiserfs_warning(s, "jdm-2005",
947 "xattrs/ACLs not supported "
948 "on pre-v3.6 format filesystems. "
949 "Failing mount.");
950 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700951 }
952 }
953
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400954 return 0;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700955}
956
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400957int reiserfs_permission(struct inode *inode, int mask)
958{
959 /*
960 * We don't do permission checks on the internal objects.
961 * Permissions are determined by the "owning" object.
962 */
963 if (IS_PRIVATE(inode))
964 return 0;
965
966#ifdef CONFIG_REISERFS_FS_XATTR
967 /*
968 * Stat data v1 doesn't support ACLs.
969 */
970 if (get_inode_sd_version(inode) != STAT_DATA_V1)
971 return generic_permission(inode, mask, reiserfs_check_acl);
972#endif
973 return generic_permission(inode, mask, NULL);
974}
975
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400976static int xattr_hide_revalidate(struct dentry *dentry, struct nameidata *nd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977{
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400978 return -EPERM;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700979}
980
Al Viroe16404e2009-02-20 05:55:13 +0000981static const struct dentry_operations xattr_lookup_poison_ops = {
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400982 .d_revalidate = xattr_hide_revalidate,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983};
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700984
Al Viroedcc37a2009-05-03 06:00:05 -0400985int reiserfs_lookup_privroot(struct super_block *s)
986{
987 struct dentry *dentry;
988 int err = 0;
989
990 /* If we don't have the privroot located yet - go find it */
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +0200991 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -0400992 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
993 strlen(PRIVROOT_NAME));
994 if (!IS_ERR(dentry)) {
995 REISERFS_SB(s)->priv_root = dentry;
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400996 dentry->d_op = &xattr_lookup_poison_ops;
Al Viroedcc37a2009-05-03 06:00:05 -0400997 if (dentry->d_inode)
998 dentry->d_inode->i_flags |= S_PRIVATE;
999 } else
1000 err = PTR_ERR(dentry);
1001 mutex_unlock(&s->s_root->d_inode->i_mutex);
1002
1003 return err;
1004}
1005
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006/* We need to take a copy of the mount flags since things like
1007 * MS_RDONLY don't get set until *after* we're called.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 * mount_flags != mount_options */
1009int reiserfs_xattr_init(struct super_block *s, int mount_flags)
1010{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001011 int err = 0;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001012 struct dentry *privroot = REISERFS_SB(s)->priv_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001014 err = xattr_mount_check(s);
1015 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001016 goto error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001017
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001018 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
Frederic Weisbeckerae635c02009-08-25 02:24:45 +02001019 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -04001020 err = create_privroot(REISERFS_SB(s)->priv_root);
Jeff Mahoney5a6059c2009-05-01 12:11:12 -04001021 mutex_unlock(&s->s_root->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001022 }
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001023
1024 if (privroot->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001025 s->s_xattr = reiserfs_xattr_handlers;
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +02001026 reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001027 if (!REISERFS_SB(s)->xattr_root) {
1028 struct dentry *dentry;
1029 dentry = lookup_one_len(XAROOT_NAME, privroot,
1030 strlen(XAROOT_NAME));
1031 if (!IS_ERR(dentry))
1032 REISERFS_SB(s)->xattr_root = dentry;
1033 else
1034 err = PTR_ERR(dentry);
1035 }
1036 mutex_unlock(&privroot->d_inode->i_mutex);
1037 }
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001038
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001039error:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001040 if (err) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001041 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1042 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1043 }
1044
1045 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001046 if (reiserfs_posixacl(s))
1047 s->s_flags |= MS_POSIXACL;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001048 else
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001049 s->s_flags &= ~MS_POSIXACL;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001050
1051 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052}