blob: 8e7deb0e6964ab363feddb606efd37838575a48a [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/smp_lock.h>
50#include <linux/stat.h>
Jeff Mahoney6c176752009-03-30 14:02:34 -040051#include <linux/quotaops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Linus Torvalds1da177e2005-04-16 15:20:36 -070053#define PRIVROOT_NAME ".reiserfs_priv"
54#define XAROOT_NAME "xattrs"
55
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
Jeff Mahoney6c176752009-03-30 14:02:34 -040057/* Helpers for inode ops. We do this so that we don't have all the VFS
58 * overhead and also for proper i_mutex annotation.
59 * dir->i_mutex must be held for all of them. */
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040060#ifdef CONFIG_REISERFS_FS_XATTR
Jeff Mahoney6c176752009-03-30 14:02:34 -040061static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070062{
Jeff Mahoney6c176752009-03-30 14:02:34 -040063 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070064 vfs_dq_init(dir);
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));
Linus Torvaldse1c50242009-03-30 12:29:21 -070072 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040073 return dir->i_op->mkdir(dir, dentry, mode);
74}
75
76/* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
77 * mutation ops aren't called during rename or splace, which are the
78 * only other users of I_MUTEX_CHILD. It violates the ordering, but that's
79 * better than allocating another subclass just for this code. */
80static int xattr_unlink(struct inode *dir, struct dentry *dentry)
81{
82 int error;
83 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070084 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -040085
86 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
87 error = dir->i_op->unlink(dir, dentry);
88 mutex_unlock(&dentry->d_inode->i_mutex);
89
90 if (!error)
91 d_delete(dentry);
92 return error;
93}
94
95static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
96{
97 int error;
98 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Linus Torvaldse1c50242009-03-30 12:29:21 -070099 vfs_dq_init(dir);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400100
101 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
102 dentry_unhash(dentry);
103 error = dir->i_op->rmdir(dir, dentry);
104 if (!error)
105 dentry->d_inode->i_flags |= S_DEAD;
106 mutex_unlock(&dentry->d_inode->i_mutex);
107 if (!error)
108 d_delete(dentry);
109 dput(dentry);
110
111 return error;
112}
113
Jeff Mahoney6c176752009-03-30 14:02:34 -0400114#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
115
Jeff Mahoney6c176752009-03-30 14:02:34 -0400116static struct dentry *open_xa_root(struct super_block *sb, int flags)
117{
118 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400119 struct dentry *xaroot;
120 if (!privroot->d_inode)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400121 return ERR_PTR(-ENODATA);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400122
123 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
124
125 xaroot = dget(REISERFS_SB(sb)->xattr_root);
Jeff Mahoneyceb5edc2009-05-17 01:02:02 -0400126 if (!xaroot)
127 xaroot = ERR_PTR(-ENODATA);
128 else if (!xaroot->d_inode) {
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400129 int err = -ENODATA;
130 if (xattr_may_create(flags))
131 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
132 if (err) {
133 dput(xaroot);
134 xaroot = ERR_PTR(err);
135 }
136 }
137
138 mutex_unlock(&privroot->d_inode->i_mutex);
139 return xaroot;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400140}
141
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700142static struct dentry *open_xa_dir(const struct inode *inode, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700144 struct dentry *xaroot, *xadir;
145 char namebuf[17];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146
Jeff Mahoney6c176752009-03-30 14:02:34 -0400147 xaroot = open_xa_root(inode->i_sb, flags);
Jeff Mahoney9b7f3752007-04-23 14:41:17 -0700148 if (IS_ERR(xaroot))
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700149 return xaroot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700151 snprintf(namebuf, sizeof(namebuf), "%X.%X",
152 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
153 inode->i_generation);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400155 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
156
157 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
158 if (!IS_ERR(xadir) && !xadir->d_inode) {
159 int err = -ENODATA;
160 if (xattr_may_create(flags))
161 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
162 if (err) {
163 dput(xadir);
164 xadir = ERR_PTR(err);
165 }
166 }
167
168 mutex_unlock(&xaroot->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700169 dput(xaroot);
170 return xadir;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171}
172
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400173/* The following are side effects of other operations that aren't explicitly
174 * modifying extended attributes. This includes operations such as permissions
175 * or ownership changes, object deletions, etc. */
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400176struct reiserfs_dentry_buf {
177 struct dentry *xadir;
178 int count;
179 struct dentry *dentries[8];
180};
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400181
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400182static int
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400183fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
184 u64 ino, unsigned int d_type)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400185{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400186 struct reiserfs_dentry_buf *dbuf = buf;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400187 struct dentry *dentry;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400188 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400189
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400190 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
191 return -ENOSPC;
192
193 if (name[0] == '.' && (name[1] == '\0' ||
194 (name[1] == '.' && name[2] == '\0')))
195 return 0;
196
197 dentry = lookup_one_len(name, dbuf->xadir, namelen);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400198 if (IS_ERR(dentry)) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400199 return PTR_ERR(dentry);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400200 } else if (!dentry->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400201 /* A directory entry exists, but no file? */
202 reiserfs_error(dentry->d_sb, "xattr-20003",
203 "Corrupted directory: xattr %s listed but "
204 "not found for file %s.\n",
205 dentry->d_name.name, dbuf->xadir->d_name.name);
206 dput(dentry);
207 return -EIO;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400208 }
209
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400210 dbuf->dentries[dbuf->count++] = dentry;
211 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400212}
213
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400214static void
215cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400216{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400217 int i;
218 for (i = 0; i < buf->count; i++)
219 if (buf->dentries[i])
220 dput(buf->dentries[i]);
221}
222
223static int reiserfs_for_each_xattr(struct inode *inode,
224 int (*action)(struct dentry *, void *),
225 void *data)
226{
227 struct dentry *dir;
228 int i, err = 0;
229 loff_t pos = 0;
230 struct reiserfs_dentry_buf buf = {
231 .count = 0,
232 };
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400233
234 /* Skip out, an xattr has no xattrs associated with it */
235 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
236 return 0;
237
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);
241 goto out;
242 } else if (!dir->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400243 err = 0;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400244 goto out_dir;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400245 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400246
Jeff Mahoney6c176752009-03-30 14:02:34 -0400247 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400248 buf.xadir = dir;
249 err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
250 while ((err == 0 || err == -ENOSPC) && buf.count) {
251 err = 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400252
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400253 for (i = 0; i < buf.count && buf.dentries[i]; i++) {
254 int lerr = 0;
255 struct dentry *dentry = buf.dentries[i];
256
257 if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
258 lerr = action(dentry, data);
259
260 dput(dentry);
261 buf.dentries[i] = NULL;
262 err = lerr ?: err;
263 }
264 buf.count = 0;
265 if (!err)
266 err = reiserfs_readdir_dentry(dir, &buf,
267 fill_with_dentries, &pos);
268 }
Jeff Mahoney6c176752009-03-30 14:02:34 -0400269 mutex_unlock(&dir->d_inode->i_mutex);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400270
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400271 /* Clean up after a failed readdir */
272 cleanup_dentry_buf(&buf);
273
274 if (!err) {
275 /* We start a transaction here to avoid a ABBA situation
276 * between the xattr root's i_mutex and the journal lock.
277 * This doesn't incur much additional overhead since the
278 * new transaction will just nest inside the
279 * outer transaction. */
280 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
281 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
282 struct reiserfs_transaction_handle th;
283 err = journal_begin(&th, inode->i_sb, blocks);
284 if (!err) {
285 int jerror;
286 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
287 I_MUTEX_XATTR);
288 err = action(dir, data);
289 jerror = journal_end(&th, inode->i_sb, blocks);
290 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
291 err = jerror ?: err;
292 }
293 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400294out_dir:
295 dput(dir);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400296out:
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400297 /* -ENODATA isn't an error */
298 if (err == -ENODATA)
299 err = 0;
300 return err;
301}
302
303static int delete_one_xattr(struct dentry *dentry, void *data)
304{
305 struct inode *dir = dentry->d_parent->d_inode;
306
307 /* This is the xattr dir, handle specially. */
308 if (S_ISDIR(dentry->d_inode->i_mode))
309 return xattr_rmdir(dir, dentry);
310
311 return xattr_unlink(dir, dentry);
312}
313
314static int chown_one_xattr(struct dentry *dentry, void *data)
315{
316 struct iattr *attrs = data;
317 return reiserfs_setattr(dentry, attrs);
318}
319
320/* No i_mutex, but the inode is unconnected. */
321int reiserfs_delete_xattrs(struct inode *inode)
322{
323 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
324 if (err)
325 reiserfs_warning(inode->i_sb, "jdm-20004",
326 "Couldn't delete all xattrs (%d)\n", err);
327 return err;
328}
329
330/* inode->i_mutex: down */
331int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
332{
333 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400334 if (err)
335 reiserfs_warning(inode->i_sb, "jdm-20007",
336 "Couldn't chown all xattrs (%d)\n", err);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400337 return err;
338}
339
340#ifdef CONFIG_REISERFS_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341/* Returns a dentry corresponding to a specific extended attribute file
342 * for the inode. If flags allow, the file is created. Otherwise, a
343 * valid or negative dentry, or an error is returned. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400344static struct dentry *xattr_lookup(struct inode *inode, const char *name,
345 int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700347 struct dentry *xadir, *xafile;
348 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700350 xadir = open_xa_dir(inode, flags);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400351 if (IS_ERR(xadir))
David Howellse231c2e2008-02-07 00:15:26 -0800352 return ERR_CAST(xadir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400354 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700355 xafile = lookup_one_len(name, xadir, strlen(name));
356 if (IS_ERR(xafile)) {
Jeff Mahoney6c176752009-03-30 14:02:34 -0400357 err = PTR_ERR(xafile);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700358 goto out;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400359 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
Jeff Mahoney6c176752009-03-30 14:02:34 -0400361 if (xafile->d_inode && (flags & XATTR_CREATE))
362 err = -EEXIST;
363
364 if (!xafile->d_inode) {
365 err = -ENODATA;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400366 if (xattr_may_create(flags))
Jeff Mahoney6c176752009-03-30 14:02:34 -0400367 err = xattr_create(xadir->d_inode, xafile,
368 0700|S_IFREG);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
Jeff Mahoney6c176752009-03-30 14:02:34 -0400371 if (err)
372 dput(xafile);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400373out:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400374 mutex_unlock(&xadir->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700375 dput(xadir);
376 if (err)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400377 return ERR_PTR(err);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800378 return xafile;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379}
380
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381/* Internal operations on file data */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700382static inline void reiserfs_put_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700384 kunmap(page);
385 page_cache_release(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386}
387
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400388static struct page *reiserfs_get_page(struct inode *dir, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700390 struct address_space *mapping = dir->i_mapping;
391 struct page *page;
392 /* We can deadlock if we try to free dentries,
393 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
Al Viroc4cdd032005-10-21 03:22:39 -0400394 mapping_set_gfp_mask(mapping, GFP_NOFS);
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400395 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700396 if (!IS_ERR(page)) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700397 kmap(page);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700398 if (PageError(page))
399 goto fail;
400 }
401 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700403 fail:
404 reiserfs_put_page(page);
405 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406}
407
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700408static inline __u32 xattr_hash(const char *msg, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700410 return csum_partial(msg, len, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411}
412
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700413int reiserfs_commit_write(struct file *f, struct page *page,
414 unsigned from, unsigned to);
415int reiserfs_prepare_write(struct file *f, struct page *page,
416 unsigned from, unsigned to);
417
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400418static void update_ctime(struct inode *inode)
419{
420 struct timespec now = current_fs_time(inode->i_sb);
421 if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink ||
422 timespec_equal(&inode->i_ctime, &now))
423 return;
424
425 inode->i_ctime = CURRENT_TIME_SEC;
426 mark_inode_dirty(inode);
427}
428
429static int lookup_and_delete_xattr(struct inode *inode, const char *name)
430{
431 int err = 0;
432 struct dentry *dentry, *xadir;
433
434 xadir = open_xa_dir(inode, XATTR_REPLACE);
435 if (IS_ERR(xadir))
436 return PTR_ERR(xadir);
437
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400438 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400439 dentry = lookup_one_len(name, xadir, strlen(name));
440 if (IS_ERR(dentry)) {
441 err = PTR_ERR(dentry);
442 goto out_dput;
443 }
444
445 if (dentry->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400446 err = xattr_unlink(xadir->d_inode, dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400447 update_ctime(inode);
448 }
449
450 dput(dentry);
451out_dput:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400452 mutex_unlock(&xadir->d_inode->i_mutex);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400453 dput(xadir);
454 return err;
455}
456
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700457
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458/* Generic extended attribute operations that can be used by xa plugins */
459
460/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800461 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 */
463int
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400464reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
465 struct inode *inode, const char *name,
466 const void *buffer, size_t buffer_size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700468 int err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800469 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700470 struct page *page;
471 char *data;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700472 size_t file_pos = 0;
473 size_t buffer_pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400474 size_t new_size;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700475 __u32 xahash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700477 if (get_inode_sd_version(inode) == STAT_DATA_V1)
478 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400480 if (!buffer)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400481 return lookup_and_delete_xattr(inode, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400483 dentry = xattr_lookup(inode, name, flags);
484 if (IS_ERR(dentry))
485 return PTR_ERR(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400487 down_write(&REISERFS_I(inode)->i_xattr_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400489 xahash = xattr_hash(buffer, buffer_size);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700490 while (buffer_pos < buffer_size || buffer_pos == 0) {
491 size_t chunk;
492 size_t skip = 0;
493 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
494 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
495 chunk = PAGE_CACHE_SIZE;
496 else
497 chunk = buffer_size - buffer_pos;
498
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400499 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700500 if (IS_ERR(page)) {
501 err = PTR_ERR(page);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400502 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700503 }
504
505 lock_page(page);
506 data = page_address(page);
507
508 if (file_pos == 0) {
509 struct reiserfs_xattr_header *rxh;
510 skip = file_pos = sizeof(struct reiserfs_xattr_header);
511 if (chunk + skip > PAGE_CACHE_SIZE)
512 chunk = PAGE_CACHE_SIZE - skip;
513 rxh = (struct reiserfs_xattr_header *)data;
514 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
515 rxh->h_hash = cpu_to_le32(xahash);
516 }
517
Jeff Mahoney3227e142008-02-15 14:37:22 -0800518 err = reiserfs_prepare_write(NULL, page, page_offset,
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700519 page_offset + chunk + skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700520 if (!err) {
521 if (buffer)
522 memcpy(data + skip, buffer + buffer_pos, chunk);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800523 err = reiserfs_commit_write(NULL, page, page_offset,
524 page_offset + chunk +
525 skip);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700526 }
527 unlock_page(page);
528 reiserfs_put_page(page);
529 buffer_pos += chunk;
530 file_pos += chunk;
531 skip = 0;
532 if (err || buffer_size == 0 || !buffer)
533 break;
534 }
535
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400536 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
537 if (!err && new_size < i_size_read(dentry->d_inode)) {
538 struct iattr newattrs = {
539 .ia_ctime = current_fs_time(inode->i_sb),
540 .ia_size = buffer_size,
541 .ia_valid = ATTR_SIZE | ATTR_CTIME,
542 };
543 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
544 down_write(&dentry->d_inode->i_alloc_sem);
545 err = reiserfs_setattr(dentry, &newattrs);
546 up_write(&dentry->d_inode->i_alloc_sem);
547 mutex_unlock(&dentry->d_inode->i_mutex);
548 } else
549 update_ctime(inode);
550out_unlock:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400551 up_write(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800552 dput(dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400553 return err;
554}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700555
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400556/* We need to start a transaction to maintain lock ordering */
557int reiserfs_xattr_set(struct inode *inode, const char *name,
558 const void *buffer, size_t buffer_size, int flags)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400559{
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400560
561 struct reiserfs_transaction_handle th;
562 int error, error2;
563 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
564
565 if (!(flags & XATTR_REPLACE))
566 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
567
568 reiserfs_write_lock(inode->i_sb);
569 error = journal_begin(&th, inode->i_sb, jbegin_count);
570 if (error) {
571 reiserfs_write_unlock(inode->i_sb);
572 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700573 }
574
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400575 error = reiserfs_xattr_set_handle(&th, inode, name,
576 buffer, buffer_size, flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700577
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400578 error2 = journal_end(&th, inode->i_sb, jbegin_count);
579 if (error == 0)
580 error = error2;
581 reiserfs_write_unlock(inode->i_sb);
582
583 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584}
585
586/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800587 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 */
589int
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400590reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700591 size_t buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700593 ssize_t err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800594 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700595 size_t isize;
596 size_t file_pos = 0;
597 size_t buffer_pos = 0;
598 struct page *page;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700599 __u32 hash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700601 if (name == NULL)
602 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700604 /* We can't have xattrs attached to v1 items since they don't have
605 * generation numbers */
606 if (get_inode_sd_version(inode) == STAT_DATA_V1)
607 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400609 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800610 if (IS_ERR(dentry)) {
611 err = PTR_ERR(dentry);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700612 goto out;
613 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400615 down_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoneyd9845612009-03-30 14:02:35 -0400616
Jeff Mahoneyf437c522009-03-30 14:02:29 -0400617 isize = i_size_read(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700619 /* Just return the size needed */
620 if (buffer == NULL) {
621 err = isize - sizeof(struct reiserfs_xattr_header);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400622 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700623 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700625 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
626 err = -ERANGE;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400627 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700628 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700630 while (file_pos < isize) {
631 size_t chunk;
632 char *data;
633 size_t skip = 0;
634 if (isize - file_pos > PAGE_CACHE_SIZE)
635 chunk = PAGE_CACHE_SIZE;
636 else
637 chunk = isize - file_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400639 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700640 if (IS_ERR(page)) {
641 err = PTR_ERR(page);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400642 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700643 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700645 lock_page(page);
646 data = page_address(page);
647 if (file_pos == 0) {
648 struct reiserfs_xattr_header *rxh =
649 (struct reiserfs_xattr_header *)data;
650 skip = file_pos = sizeof(struct reiserfs_xattr_header);
651 chunk -= skip;
652 /* Magic doesn't match up.. */
653 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
654 unlock_page(page);
655 reiserfs_put_page(page);
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400656 reiserfs_warning(inode->i_sb, "jdm-20001",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700657 "Invalid magic for xattr (%s) "
658 "associated with %k", name,
659 INODE_PKEY(inode));
660 err = -EIO;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400661 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700662 }
663 hash = le32_to_cpu(rxh->h_hash);
664 }
665 memcpy(buffer + buffer_pos, data + skip, chunk);
666 unlock_page(page);
667 reiserfs_put_page(page);
668 file_pos += chunk;
669 buffer_pos += chunk;
670 skip = 0;
671 }
672 err = isize - sizeof(struct reiserfs_xattr_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700674 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
675 hash) {
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400676 reiserfs_warning(inode->i_sb, "jdm-20002",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700677 "Invalid hash for xattr (%s) associated "
678 "with %k", name, INODE_PKEY(inode));
679 err = -EIO;
680 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400682out_unlock:
683 up_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800684 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400686out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700687 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688}
689
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400690/*
691 * In order to implement different sets of xattr operations for each xattr
692 * prefix with the generic xattr API, a filesystem should create a
693 * null-terminated array of struct xattr_handler (one for each prefix) and
694 * hang a pointer to it off of the s_xattr field of the superblock.
695 *
696 * The generic_fooxattr() functions will use this list to dispatch xattr
697 * operations to the correct xattr_handler.
698 */
699#define for_each_xattr_handler(handlers, handler) \
700 for ((handler) = *(handlers)++; \
701 (handler) != NULL; \
702 (handler) = *(handlers)++)
703
704/* This is the implementation for the xattr plugin infrastructure */
705static inline struct xattr_handler *
706find_xattr_handler_prefix(struct xattr_handler **handlers,
707 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400709 struct xattr_handler *xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400711 if (!handlers)
712 return NULL;
713
714 for_each_xattr_handler(handlers, xah) {
715 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
716 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 }
718
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400719 return xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720}
721
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
723/*
724 * Inode operation getxattr()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 */
726ssize_t
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700727reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
728 size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400730 struct inode *inode = dentry->d_inode;
731 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400733 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
734
735 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700736 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400738 return handler->get(inode, name, buffer, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739}
740
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741/*
742 * Inode operation setxattr()
743 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800744 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 */
746int
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700747reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
748 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400750 struct inode *inode = dentry->d_inode;
751 struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400753 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
754
755 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700756 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400758 return handler->set(inode, name, value, size, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759}
760
761/*
762 * Inode operation removexattr()
763 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800764 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700766int reiserfs_removexattr(struct dentry *dentry, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400768 struct inode *inode = dentry->d_inode;
769 struct xattr_handler *handler;
770 handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400772 if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700773 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400775 return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776}
777
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400778struct listxattr_buf {
779 size_t size;
780 size_t pos;
781 char *buf;
782 struct inode *inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783};
784
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400785static int listxattr_filler(void *buf, const char *name, int namelen,
786 loff_t offset, u64 ino, unsigned int d_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400788 struct listxattr_buf *b = (struct listxattr_buf *)buf;
789 size_t size;
790 if (name[0] != '.' ||
791 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
792 struct xattr_handler *handler;
793 handler = find_xattr_handler_prefix(b->inode->i_sb->s_xattr,
794 name);
795 if (!handler) /* Unsupported xattr name */
796 return 0;
797 if (b->buf) {
798 size = handler->list(b->inode, b->buf + b->pos,
799 b->size, name, namelen);
800 if (size > b->size)
801 return -ERANGE;
802 } else {
803 size = handler->list(b->inode, NULL, 0, name, namelen);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700804 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400806 b->pos += size;
807 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700808 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700810
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811/*
812 * Inode operation listxattr()
813 *
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400814 * We totally ignore the generic listxattr here because it would be stupid
815 * not to. Since the xattrs are organized in a directory, we can just
816 * readdir to find them.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700818ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700820 struct dentry *dir;
821 int err = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400822 loff_t pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400823 struct listxattr_buf buf = {
824 .inode = dentry->d_inode,
825 .buf = buffer,
826 .size = buffer ? size : 0,
827 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700829 if (!dentry->d_inode)
830 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831
Jeff Mahoney677c9b22009-05-05 15:30:17 -0400832 if (!dentry->d_sb->s_xattr ||
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700833 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
834 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
Jeff Mahoney6c176752009-03-30 14:02:34 -0400836 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700837 if (IS_ERR(dir)) {
838 err = PTR_ERR(dir);
839 if (err == -ENODATA)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400840 err = 0; /* Not an error if there aren't any xattrs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700841 goto out;
842 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
Jeff Mahoney6c176752009-03-30 14:02:34 -0400844 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400845 err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400846 mutex_unlock(&dir->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400848 if (!err)
849 err = buf.pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850
Jeff Mahoney3227e142008-02-15 14:37:22 -0800851 dput(dir);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400852out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700853 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854}
855
Christoph Hellwigec191572006-02-01 03:06:46 -0800856static int reiserfs_check_acl(struct inode *inode, int mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857{
Christoph Hellwigec191572006-02-01 03:06:46 -0800858 struct posix_acl *acl;
859 int error = -EAGAIN; /* do regular unix permission checks by default */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700860
Christoph Hellwigec191572006-02-01 03:06:46 -0800861 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
862
Christoph Hellwigec191572006-02-01 03:06:46 -0800863 if (acl) {
864 if (!IS_ERR(acl)) {
865 error = posix_acl_permission(inode, acl, mask);
866 posix_acl_release(acl);
867 } else if (PTR_ERR(acl) != -ENODATA)
868 error = PTR_ERR(acl);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700869 }
870
Christoph Hellwigec191572006-02-01 03:06:46 -0800871 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700872}
873
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400874static int create_privroot(struct dentry *dentry)
875{
876 int err;
877 struct inode *inode = dentry->d_parent->d_inode;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400878 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
879
Jeff Mahoney6c176752009-03-30 14:02:34 -0400880 err = xattr_mkdir(inode, dentry, 0700);
Al Viroedcc37a2009-05-03 06:00:05 -0400881 if (err || !dentry->d_inode) {
882 reiserfs_warning(dentry->d_sb, "jdm-20006",
883 "xattrs/ACLs enabled and couldn't "
884 "find/create .reiserfs_priv. "
885 "Failing mount.");
886 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700887 }
888
Al Viroedcc37a2009-05-03 06:00:05 -0400889 dentry->d_inode->i_flags |= S_PRIVATE;
890 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
891 "storage.\n", PRIVROOT_NAME);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700892
Al Viroedcc37a2009-05-03 06:00:05 -0400893 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400894}
895
Jeff Mahoney12abb352009-05-17 01:02:01 -0400896#else
897int __init reiserfs_xattr_register_handlers(void) { return 0; }
898void reiserfs_xattr_unregister_handlers(void) {}
899static int create_privroot(struct dentry *dentry) { return 0; }
900#endif
901
902/* Actual operations that are exported to VFS-land */
903struct xattr_handler *reiserfs_xattr_handlers[] = {
904#ifdef CONFIG_REISERFS_FS_XATTR
905 &reiserfs_xattr_user_handler,
906 &reiserfs_xattr_trusted_handler,
907#endif
908#ifdef CONFIG_REISERFS_FS_SECURITY
909 &reiserfs_xattr_security_handler,
910#endif
911#ifdef CONFIG_REISERFS_FS_POSIX_ACL
912 &reiserfs_posix_acl_access_handler,
913 &reiserfs_posix_acl_default_handler,
914#endif
915 NULL
916};
917
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400918static int xattr_mount_check(struct super_block *s)
919{
920 /* We need generation numbers to ensure that the oid mapping is correct
921 * v3.5 filesystems don't have them. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400922 if (old_format_only(s)) {
923 if (reiserfs_xattrs_optional(s)) {
924 /* Old format filesystem, but optional xattrs have
925 * been enabled. Error out. */
926 reiserfs_warning(s, "jdm-2005",
927 "xattrs/ACLs not supported "
928 "on pre-v3.6 format filesystems. "
929 "Failing mount.");
930 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700931 }
932 }
933
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400934 return 0;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700935}
936
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400937int reiserfs_permission(struct inode *inode, int mask)
938{
939 /*
940 * We don't do permission checks on the internal objects.
941 * Permissions are determined by the "owning" object.
942 */
943 if (IS_PRIVATE(inode))
944 return 0;
945
946#ifdef CONFIG_REISERFS_FS_XATTR
947 /*
948 * Stat data v1 doesn't support ACLs.
949 */
950 if (get_inode_sd_version(inode) != STAT_DATA_V1)
951 return generic_permission(inode, mask, reiserfs_check_acl);
952#endif
953 return generic_permission(inode, mask, NULL);
954}
955
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956/* This will catch lookups from the fs root to .reiserfs_priv */
957static int
958xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
959{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700960 struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
Al Viroedcc37a2009-05-03 06:00:05 -0400961 if (container_of(q1, struct dentry, d_name) == priv_root)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700962 return -ENOENT;
Al Viroedcc37a2009-05-03 06:00:05 -0400963 if (q1->len == name->len &&
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700964 !memcmp(q1->name, name->name, name->len))
965 return 0;
966 return 1;
967}
968
Al Viroe16404e2009-02-20 05:55:13 +0000969static const struct dentry_operations xattr_lookup_poison_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 .d_compare = xattr_lookup_poison,
971};
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700972
Al Viroedcc37a2009-05-03 06:00:05 -0400973int reiserfs_lookup_privroot(struct super_block *s)
974{
975 struct dentry *dentry;
976 int err = 0;
977
978 /* If we don't have the privroot located yet - go find it */
979 mutex_lock(&s->s_root->d_inode->i_mutex);
980 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
981 strlen(PRIVROOT_NAME));
982 if (!IS_ERR(dentry)) {
983 REISERFS_SB(s)->priv_root = dentry;
984 s->s_root->d_op = &xattr_lookup_poison_ops;
985 if (dentry->d_inode)
986 dentry->d_inode->i_flags |= S_PRIVATE;
987 } else
988 err = PTR_ERR(dentry);
989 mutex_unlock(&s->s_root->d_inode->i_mutex);
990
991 return err;
992}
993
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994/* We need to take a copy of the mount flags since things like
995 * MS_RDONLY don't get set until *after* we're called.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 * mount_flags != mount_options */
997int reiserfs_xattr_init(struct super_block *s, int mount_flags)
998{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700999 int err = 0;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001000 struct dentry *privroot = REISERFS_SB(s)->priv_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001002 err = xattr_mount_check(s);
1003 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001004 goto error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001005
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001006 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
Al Viroedcc37a2009-05-03 06:00:05 -04001007 mutex_lock(&s->s_root->d_inode->i_mutex);
1008 err = create_privroot(REISERFS_SB(s)->priv_root);
Jeff Mahoney5a6059c2009-05-01 12:11:12 -04001009 mutex_unlock(&s->s_root->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001010 }
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001011
1012 if (privroot->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001013 s->s_xattr = reiserfs_xattr_handlers;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001014 mutex_lock(&privroot->d_inode->i_mutex);
1015 if (!REISERFS_SB(s)->xattr_root) {
1016 struct dentry *dentry;
1017 dentry = lookup_one_len(XAROOT_NAME, privroot,
1018 strlen(XAROOT_NAME));
1019 if (!IS_ERR(dentry))
1020 REISERFS_SB(s)->xattr_root = dentry;
1021 else
1022 err = PTR_ERR(dentry);
1023 }
1024 mutex_unlock(&privroot->d_inode->i_mutex);
1025 }
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001026
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001027error:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001028 if (err) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001029 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1030 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1031 }
1032
1033 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001034 if (reiserfs_posixacl(s))
1035 s->s_flags |= MS_POSIXACL;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001036 else
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001037 s->s_flags &= ~MS_POSIXACL;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001038
1039 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040}