blob: 78a3f246295c04541db0589c1eba4c2aea88f6ed [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
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
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100249 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
250
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;
291 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
292 I_MUTEX_XATTR);
293 err = action(dir, data);
294 jerror = journal_end(&th, inode->i_sb, blocks);
295 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
296 err = jerror ?: err;
297 }
298 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400299out_dir:
300 dput(dir);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400301out:
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400302 /* -ENODATA isn't an error */
303 if (err == -ENODATA)
304 err = 0;
305 return err;
306}
307
308static int delete_one_xattr(struct dentry *dentry, void *data)
309{
310 struct inode *dir = dentry->d_parent->d_inode;
311
312 /* This is the xattr dir, handle specially. */
313 if (S_ISDIR(dentry->d_inode->i_mode))
314 return xattr_rmdir(dir, dentry);
315
316 return xattr_unlink(dir, dentry);
317}
318
319static int chown_one_xattr(struct dentry *dentry, void *data)
320{
321 struct iattr *attrs = data;
322 return reiserfs_setattr(dentry, attrs);
323}
324
325/* No i_mutex, but the inode is unconnected. */
326int reiserfs_delete_xattrs(struct inode *inode)
327{
328 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
329 if (err)
330 reiserfs_warning(inode->i_sb, "jdm-20004",
331 "Couldn't delete all xattrs (%d)\n", err);
332 return err;
333}
334
335/* inode->i_mutex: down */
336int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
337{
338 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400339 if (err)
340 reiserfs_warning(inode->i_sb, "jdm-20007",
341 "Couldn't chown all xattrs (%d)\n", err);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400342 return err;
343}
344
345#ifdef CONFIG_REISERFS_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346/* Returns a dentry corresponding to a specific extended attribute file
347 * for the inode. If flags allow, the file is created. Otherwise, a
348 * valid or negative dentry, or an error is returned. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400349static struct dentry *xattr_lookup(struct inode *inode, const char *name,
350 int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700352 struct dentry *xadir, *xafile;
353 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700355 xadir = open_xa_dir(inode, flags);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400356 if (IS_ERR(xadir))
David Howellse231c2e2008-02-07 00:15:26 -0800357 return ERR_CAST(xadir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400359 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700360 xafile = lookup_one_len(name, xadir, strlen(name));
361 if (IS_ERR(xafile)) {
Jeff Mahoney6c176752009-03-30 14:02:34 -0400362 err = PTR_ERR(xafile);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700363 goto out;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400364 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
Jeff Mahoney6c176752009-03-30 14:02:34 -0400366 if (xafile->d_inode && (flags & XATTR_CREATE))
367 err = -EEXIST;
368
369 if (!xafile->d_inode) {
370 err = -ENODATA;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400371 if (xattr_may_create(flags))
Jeff Mahoney6c176752009-03-30 14:02:34 -0400372 err = xattr_create(xadir->d_inode, xafile,
373 0700|S_IFREG);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700374 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375
Jeff Mahoney6c176752009-03-30 14:02:34 -0400376 if (err)
377 dput(xafile);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400378out:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400379 mutex_unlock(&xadir->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700380 dput(xadir);
381 if (err)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400382 return ERR_PTR(err);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800383 return xafile;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384}
385
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386/* Internal operations on file data */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700387static inline void reiserfs_put_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700389 kunmap(page);
390 page_cache_release(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391}
392
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400393static struct page *reiserfs_get_page(struct inode *dir, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700395 struct address_space *mapping = dir->i_mapping;
396 struct page *page;
397 /* We can deadlock if we try to free dentries,
398 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
Al Viroc4cdd032005-10-21 03:22:39 -0400399 mapping_set_gfp_mask(mapping, GFP_NOFS);
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400400 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700401 if (!IS_ERR(page)) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700402 kmap(page);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700403 if (PageError(page))
404 goto fail;
405 }
406 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700408 fail:
409 reiserfs_put_page(page);
410 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411}
412
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700413static inline __u32 xattr_hash(const char *msg, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700415 return csum_partial(msg, len, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416}
417
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700418int reiserfs_commit_write(struct file *f, struct page *page,
419 unsigned from, unsigned to);
420int reiserfs_prepare_write(struct file *f, struct page *page,
421 unsigned from, unsigned to);
422
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400423static void update_ctime(struct inode *inode)
424{
425 struct timespec now = current_fs_time(inode->i_sb);
426 if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink ||
427 timespec_equal(&inode->i_ctime, &now))
428 return;
429
430 inode->i_ctime = CURRENT_TIME_SEC;
431 mark_inode_dirty(inode);
432}
433
434static int lookup_and_delete_xattr(struct inode *inode, const char *name)
435{
436 int err = 0;
437 struct dentry *dentry, *xadir;
438
439 xadir = open_xa_dir(inode, XATTR_REPLACE);
440 if (IS_ERR(xadir))
441 return PTR_ERR(xadir);
442
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400443 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400444 dentry = lookup_one_len(name, xadir, strlen(name));
445 if (IS_ERR(dentry)) {
446 err = PTR_ERR(dentry);
447 goto out_dput;
448 }
449
450 if (dentry->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400451 err = xattr_unlink(xadir->d_inode, dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400452 update_ctime(inode);
453 }
454
455 dput(dentry);
456out_dput:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400457 mutex_unlock(&xadir->d_inode->i_mutex);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400458 dput(xadir);
459 return err;
460}
461
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700462
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463/* Generic extended attribute operations that can be used by xa plugins */
464
465/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800466 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 */
468int
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400469reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
470 struct inode *inode, const char *name,
471 const void *buffer, size_t buffer_size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700473 int err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800474 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700475 struct page *page;
476 char *data;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700477 size_t file_pos = 0;
478 size_t buffer_pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400479 size_t new_size;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700480 __u32 xahash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700482 if (get_inode_sd_version(inode) == STAT_DATA_V1)
483 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400485 if (!buffer)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400486 return lookup_and_delete_xattr(inode, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100488 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400489 dentry = xattr_lookup(inode, name, flags);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100490 if (IS_ERR(dentry)) {
491 reiserfs_write_lock(inode->i_sb);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400492 return PTR_ERR(dentry);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100493 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100495 down_read(&REISERFS_I(inode)->i_xattr_sem);
496
497 reiserfs_write_lock(inode->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400499 xahash = xattr_hash(buffer, buffer_size);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700500 while (buffer_pos < buffer_size || buffer_pos == 0) {
501 size_t chunk;
502 size_t skip = 0;
503 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
504 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
505 chunk = PAGE_CACHE_SIZE;
506 else
507 chunk = buffer_size - buffer_pos;
508
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400509 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700510 if (IS_ERR(page)) {
511 err = PTR_ERR(page);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400512 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700513 }
514
515 lock_page(page);
516 data = page_address(page);
517
518 if (file_pos == 0) {
519 struct reiserfs_xattr_header *rxh;
520 skip = file_pos = sizeof(struct reiserfs_xattr_header);
521 if (chunk + skip > PAGE_CACHE_SIZE)
522 chunk = PAGE_CACHE_SIZE - skip;
523 rxh = (struct reiserfs_xattr_header *)data;
524 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
525 rxh->h_hash = cpu_to_le32(xahash);
526 }
527
Jeff Mahoney3227e142008-02-15 14:37:22 -0800528 err = reiserfs_prepare_write(NULL, page, page_offset,
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700529 page_offset + chunk + skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700530 if (!err) {
531 if (buffer)
532 memcpy(data + skip, buffer + buffer_pos, chunk);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800533 err = reiserfs_commit_write(NULL, page, page_offset,
534 page_offset + chunk +
535 skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700536 }
537 unlock_page(page);
538 reiserfs_put_page(page);
539 buffer_pos += chunk;
540 file_pos += chunk;
541 skip = 0;
542 if (err || buffer_size == 0 || !buffer)
543 break;
544 }
545
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400546 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
547 if (!err && new_size < i_size_read(dentry->d_inode)) {
548 struct iattr newattrs = {
549 .ia_ctime = current_fs_time(inode->i_sb),
550 .ia_size = buffer_size,
551 .ia_valid = ATTR_SIZE | ATTR_CTIME,
552 };
553 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
554 down_write(&dentry->d_inode->i_alloc_sem);
555 err = reiserfs_setattr(dentry, &newattrs);
556 up_write(&dentry->d_inode->i_alloc_sem);
557 mutex_unlock(&dentry->d_inode->i_mutex);
558 } else
559 update_ctime(inode);
560out_unlock:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400561 up_write(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800562 dput(dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400563 return err;
564}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700565
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400566/* We need to start a transaction to maintain lock ordering */
567int reiserfs_xattr_set(struct inode *inode, const char *name,
568 const void *buffer, size_t buffer_size, int flags)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400569{
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400570
571 struct reiserfs_transaction_handle th;
572 int error, error2;
573 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
574
575 if (!(flags & XATTR_REPLACE))
576 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
577
578 reiserfs_write_lock(inode->i_sb);
579 error = journal_begin(&th, inode->i_sb, jbegin_count);
580 if (error) {
581 reiserfs_write_unlock(inode->i_sb);
582 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700583 }
584
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400585 error = reiserfs_xattr_set_handle(&th, inode, name,
586 buffer, buffer_size, flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700587
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400588 error2 = journal_end(&th, inode->i_sb, jbegin_count);
589 if (error == 0)
590 error = error2;
591 reiserfs_write_unlock(inode->i_sb);
592
593 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594}
595
596/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800597 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 */
599int
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400600reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700601 size_t buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700603 ssize_t err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800604 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700605 size_t isize;
606 size_t file_pos = 0;
607 size_t buffer_pos = 0;
608 struct page *page;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700609 __u32 hash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700611 if (name == NULL)
612 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700614 /* We can't have xattrs attached to v1 items since they don't have
615 * generation numbers */
616 if (get_inode_sd_version(inode) == STAT_DATA_V1)
617 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400619 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800620 if (IS_ERR(dentry)) {
621 err = PTR_ERR(dentry);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700622 goto out;
623 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400625 down_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoneyd9845612009-03-30 14:02:35 -0400626
Jeff Mahoneyf437c522009-03-30 14:02:29 -0400627 isize = i_size_read(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700629 /* Just return the size needed */
630 if (buffer == NULL) {
631 err = isize - sizeof(struct reiserfs_xattr_header);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400632 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700633 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700635 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
636 err = -ERANGE;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400637 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700638 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700640 while (file_pos < isize) {
641 size_t chunk;
642 char *data;
643 size_t skip = 0;
644 if (isize - file_pos > PAGE_CACHE_SIZE)
645 chunk = PAGE_CACHE_SIZE;
646 else
647 chunk = isize - file_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400649 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700650 if (IS_ERR(page)) {
651 err = PTR_ERR(page);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400652 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700653 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700655 lock_page(page);
656 data = page_address(page);
657 if (file_pos == 0) {
658 struct reiserfs_xattr_header *rxh =
659 (struct reiserfs_xattr_header *)data;
660 skip = file_pos = sizeof(struct reiserfs_xattr_header);
661 chunk -= skip;
662 /* Magic doesn't match up.. */
663 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
664 unlock_page(page);
665 reiserfs_put_page(page);
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400666 reiserfs_warning(inode->i_sb, "jdm-20001",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700667 "Invalid magic for xattr (%s) "
668 "associated with %k", name,
669 INODE_PKEY(inode));
670 err = -EIO;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400671 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700672 }
673 hash = le32_to_cpu(rxh->h_hash);
674 }
675 memcpy(buffer + buffer_pos, data + skip, chunk);
676 unlock_page(page);
677 reiserfs_put_page(page);
678 file_pos += chunk;
679 buffer_pos += chunk;
680 skip = 0;
681 }
682 err = isize - sizeof(struct reiserfs_xattr_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700684 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
685 hash) {
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400686 reiserfs_warning(inode->i_sb, "jdm-20002",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700687 "Invalid hash for xattr (%s) associated "
688 "with %k", name, INODE_PKEY(inode));
689 err = -EIO;
690 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400692out_unlock:
693 up_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800694 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400696out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700697 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698}
699
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400700/*
701 * In order to implement different sets of xattr operations for each xattr
702 * prefix with the generic xattr API, a filesystem should create a
703 * null-terminated array of struct xattr_handler (one for each prefix) and
704 * hang a pointer to it off of the s_xattr field of the superblock.
705 *
706 * The generic_fooxattr() functions will use this list to dispatch xattr
707 * operations to the correct xattr_handler.
708 */
709#define for_each_xattr_handler(handlers, handler) \
710 for ((handler) = *(handlers)++; \
711 (handler) != NULL; \
712 (handler) = *(handlers)++)
713
714/* This is the implementation for the xattr plugin infrastructure */
715static inline struct xattr_handler *
716find_xattr_handler_prefix(struct xattr_handler **handlers,
717 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400719 struct xattr_handler *xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400721 if (!handlers)
722 return NULL;
723
724 for_each_xattr_handler(handlers, xah) {
725 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
726 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 }
728
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400729 return xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730}
731
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
733/*
734 * Inode operation getxattr()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735 */
736ssize_t
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700737reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
738 size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400740 struct inode *inode = dentry->d_inode;
741 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400743 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
744
745 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700746 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400748 return handler->get(inode, name, buffer, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749}
750
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751/*
752 * Inode operation setxattr()
753 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800754 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 */
756int
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700757reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
758 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400760 struct inode *inode = dentry->d_inode;
761 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400763 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
764
765 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700766 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400768 return handler->set(inode, name, value, size, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769}
770
771/*
772 * Inode operation removexattr()
773 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800774 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700776int reiserfs_removexattr(struct dentry *dentry, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400778 struct inode *inode = dentry->d_inode;
779 struct xattr_handler *handler;
780 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400782 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700783 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400785 return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786}
787
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400788struct listxattr_buf {
789 size_t size;
790 size_t pos;
791 char *buf;
792 struct inode *inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793};
794
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400795static int listxattr_filler(void *buf, const char *name, int namelen,
796 loff_t offset, u64 ino, unsigned int d_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400798 struct listxattr_buf *b = (struct listxattr_buf *)buf;
799 size_t size;
800 if (name[0] != '.' ||
801 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
802 struct xattr_handler *handler;
803 handler = find_xattr_handler_prefix(b->inode->i_sb->s_xattr,
804 name);
805 if (!handler) /* Unsupported xattr name */
806 return 0;
807 if (b->buf) {
808 size = handler->list(b->inode, b->buf + b->pos,
809 b->size, name, namelen);
810 if (size > b->size)
811 return -ERANGE;
812 } else {
813 size = handler->list(b->inode, NULL, 0, name, namelen);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700814 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400816 b->pos += size;
817 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700818 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700820
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821/*
822 * Inode operation listxattr()
823 *
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400824 * We totally ignore the generic listxattr here because it would be stupid
825 * not to. Since the xattrs are organized in a directory, we can just
826 * readdir to find them.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700828ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700830 struct dentry *dir;
831 int err = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400832 loff_t pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400833 struct listxattr_buf buf = {
834 .inode = dentry->d_inode,
835 .buf = buffer,
836 .size = buffer ? size : 0,
837 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700839 if (!dentry->d_inode)
840 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841
Jeff Mahoney677c9b22009-05-05 15:30:17 -0400842 if (!dentry->d_sb->s_xattr ||
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700843 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
844 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845
Jeff Mahoney6c176752009-03-30 14:02:34 -0400846 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700847 if (IS_ERR(dir)) {
848 err = PTR_ERR(dir);
849 if (err == -ENODATA)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400850 err = 0; /* Not an error if there aren't any xattrs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700851 goto out;
852 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853
Jeff Mahoney6c176752009-03-30 14:02:34 -0400854 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400855 err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400856 mutex_unlock(&dir->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400858 if (!err)
859 err = buf.pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860
Jeff Mahoney3227e142008-02-15 14:37:22 -0800861 dput(dir);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400862out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700863 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864}
865
Christoph Hellwigec191572006-02-01 03:06:46 -0800866static int reiserfs_check_acl(struct inode *inode, int mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867{
Christoph Hellwigec191572006-02-01 03:06:46 -0800868 struct posix_acl *acl;
869 int error = -EAGAIN; /* do regular unix permission checks by default */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700870
Christoph Hellwigec191572006-02-01 03:06:46 -0800871 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
872
Christoph Hellwigec191572006-02-01 03:06:46 -0800873 if (acl) {
874 if (!IS_ERR(acl)) {
875 error = posix_acl_permission(inode, acl, mask);
876 posix_acl_release(acl);
877 } else if (PTR_ERR(acl) != -ENODATA)
878 error = PTR_ERR(acl);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700879 }
880
Christoph Hellwigec191572006-02-01 03:06:46 -0800881 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700882}
883
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400884static int create_privroot(struct dentry *dentry)
885{
886 int err;
887 struct inode *inode = dentry->d_parent->d_inode;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400888 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
889
Jeff Mahoney6c176752009-03-30 14:02:34 -0400890 err = xattr_mkdir(inode, dentry, 0700);
Al Viroedcc37a2009-05-03 06:00:05 -0400891 if (err || !dentry->d_inode) {
892 reiserfs_warning(dentry->d_sb, "jdm-20006",
893 "xattrs/ACLs enabled and couldn't "
894 "find/create .reiserfs_priv. "
895 "Failing mount.");
896 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700897 }
898
Al Viroedcc37a2009-05-03 06:00:05 -0400899 dentry->d_inode->i_flags |= S_PRIVATE;
900 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
901 "storage.\n", PRIVROOT_NAME);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700902
Al Viroedcc37a2009-05-03 06:00:05 -0400903 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400904}
905
Jeff Mahoney12abb352009-05-17 01:02:01 -0400906#else
907int __init reiserfs_xattr_register_handlers(void) { return 0; }
908void reiserfs_xattr_unregister_handlers(void) {}
909static int create_privroot(struct dentry *dentry) { return 0; }
910#endif
911
912/* Actual operations that are exported to VFS-land */
913struct xattr_handler *reiserfs_xattr_handlers[] = {
914#ifdef CONFIG_REISERFS_FS_XATTR
915 &reiserfs_xattr_user_handler,
916 &reiserfs_xattr_trusted_handler,
917#endif
918#ifdef CONFIG_REISERFS_FS_SECURITY
919 &reiserfs_xattr_security_handler,
920#endif
921#ifdef CONFIG_REISERFS_FS_POSIX_ACL
922 &reiserfs_posix_acl_access_handler,
923 &reiserfs_posix_acl_default_handler,
924#endif
925 NULL
926};
927
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400928static int xattr_mount_check(struct super_block *s)
929{
930 /* We need generation numbers to ensure that the oid mapping is correct
931 * v3.5 filesystems don't have them. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400932 if (old_format_only(s)) {
933 if (reiserfs_xattrs_optional(s)) {
934 /* Old format filesystem, but optional xattrs have
935 * been enabled. Error out. */
936 reiserfs_warning(s, "jdm-2005",
937 "xattrs/ACLs not supported "
938 "on pre-v3.6 format filesystems. "
939 "Failing mount.");
940 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700941 }
942 }
943
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400944 return 0;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700945}
946
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400947int reiserfs_permission(struct inode *inode, int mask)
948{
949 /*
950 * We don't do permission checks on the internal objects.
951 * Permissions are determined by the "owning" object.
952 */
953 if (IS_PRIVATE(inode))
954 return 0;
955
956#ifdef CONFIG_REISERFS_FS_XATTR
957 /*
958 * Stat data v1 doesn't support ACLs.
959 */
960 if (get_inode_sd_version(inode) != STAT_DATA_V1)
961 return generic_permission(inode, mask, reiserfs_check_acl);
962#endif
963 return generic_permission(inode, mask, NULL);
964}
965
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966/* This will catch lookups from the fs root to .reiserfs_priv */
967static int
968xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
969{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700970 struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
Al Viroedcc37a2009-05-03 06:00:05 -0400971 if (container_of(q1, struct dentry, d_name) == priv_root)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700972 return -ENOENT;
Al Viroedcc37a2009-05-03 06:00:05 -0400973 if (q1->len == name->len &&
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700974 !memcmp(q1->name, name->name, name->len))
975 return 0;
976 return 1;
977}
978
Al Viroe16404e2009-02-20 05:55:13 +0000979static const struct dentry_operations xattr_lookup_poison_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 .d_compare = xattr_lookup_poison,
981};
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700982
Al Viroedcc37a2009-05-03 06:00:05 -0400983int reiserfs_lookup_privroot(struct super_block *s)
984{
985 struct dentry *dentry;
986 int err = 0;
987
988 /* If we don't have the privroot located yet - go find it */
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +0200989 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -0400990 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
991 strlen(PRIVROOT_NAME));
992 if (!IS_ERR(dentry)) {
993 REISERFS_SB(s)->priv_root = dentry;
Jeff Mahoney73422812009-05-10 16:05:39 -0400994 if (!reiserfs_expose_privroot(s))
995 s->s_root->d_op = &xattr_lookup_poison_ops;
Al Viroedcc37a2009-05-03 06:00:05 -0400996 if (dentry->d_inode)
997 dentry->d_inode->i_flags |= S_PRIVATE;
998 } else
999 err = PTR_ERR(dentry);
1000 mutex_unlock(&s->s_root->d_inode->i_mutex);
1001
1002 return err;
1003}
1004
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005/* We need to take a copy of the mount flags since things like
1006 * MS_RDONLY don't get set until *after* we're called.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 * mount_flags != mount_options */
1008int reiserfs_xattr_init(struct super_block *s, int mount_flags)
1009{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001010 int err = 0;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001011 struct dentry *privroot = REISERFS_SB(s)->priv_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001013 err = xattr_mount_check(s);
1014 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001015 goto error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001016
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001017 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
Frederic Weisbeckerae635c02009-08-25 02:24:45 +02001018 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
Al Viroedcc37a2009-05-03 06:00:05 -04001019 err = create_privroot(REISERFS_SB(s)->priv_root);
Jeff Mahoney5a6059c2009-05-01 12:11:12 -04001020 mutex_unlock(&s->s_root->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001021 }
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001022
1023 if (privroot->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001024 s->s_xattr = reiserfs_xattr_handlers;
Frederic Weisbeckerc72e0572009-05-16 18:12:08 +02001025 reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001026 if (!REISERFS_SB(s)->xattr_root) {
1027 struct dentry *dentry;
1028 dentry = lookup_one_len(XAROOT_NAME, privroot,
1029 strlen(XAROOT_NAME));
1030 if (!IS_ERR(dentry))
1031 REISERFS_SB(s)->xattr_root = dentry;
1032 else
1033 err = PTR_ERR(dentry);
1034 }
1035 mutex_unlock(&privroot->d_inode->i_mutex);
1036 }
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001037
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001038error:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001039 if (err) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001040 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1041 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1042 }
1043
1044 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001045 if (reiserfs_posixacl(s))
1046 s->s_flags |= MS_POSIXACL;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001047 else
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001048 s->s_flags &= ~MS_POSIXACL;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001049
1050 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051}