blob: 8a9e2dcfe004919da6fe48e4c292c7ddfeef8476 [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
Al Virof466c6f2012-03-17 01:16:43 -040036#include "reiserfs.h"
Randy Dunlap16f7e0f2006-01-11 12:17:46 -080037#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <linux/dcache.h>
39#include <linux/namei.h>
40#include <linux/errno.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090041#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/fs.h>
43#include <linux/file.h>
44#include <linux/pagemap.h>
45#include <linux/xattr.h>
Al Viroc45ac882012-03-17 00:59:06 -040046#include "xattr.h"
Al Viroa3063ab2012-03-17 01:03:10 -040047#include "acl.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <asm/uaccess.h>
Al Viro3277c392006-11-14 21:13:53 -080049#include <net/checksum.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <linux/stat.h>
Jeff Mahoney6c176752009-03-30 14:02:34 -040051#include <linux/quotaops.h>
Christoph Hellwig431547b2009-11-13 09:52:56 +000052#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
Linus Torvalds1da177e2005-04-16 15:20:36 -070054#define PRIVROOT_NAME ".reiserfs_priv"
55#define XAROOT_NAME "xattrs"
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Jeff Mahoney6c176752009-03-30 14:02:34 -040058/* Helpers for inode ops. We do this so that we don't have all the VFS
59 * overhead and also for proper i_mutex annotation.
60 * dir->i_mutex must be held for all of them. */
Jeff Mahoney3a355cc2009-03-30 16:49:58 -040061#ifdef CONFIG_REISERFS_FS_XATTR
Jeff Mahoney6c176752009-03-30 14:02:34 -040062static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
Jeff Mahoney6c176752009-03-30 14:02:34 -040064 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Al Viroebfc3b42012-06-10 18:05:36 -040065 return dir->i_op->create(dir, dentry, mode, true);
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
Al Viro18bb1db2011-07-26 01:41:39 -040069static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
Jeff Mahoney6c176752009-03-30 14:02:34 -040070{
71 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Jeff Mahoney6c176752009-03-30 14:02:34 -040072 return dir->i_op->mkdir(dir, dentry, mode);
73}
74
75/* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
76 * mutation ops aren't called during rename or splace, which are the
77 * only other users of I_MUTEX_CHILD. It violates the ordering, but that's
78 * better than allocating another subclass just for this code. */
79static int xattr_unlink(struct inode *dir, struct dentry *dentry)
80{
81 int error;
82 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Jeff Mahoney6c176752009-03-30 14:02:34 -040083
Jeff Mahoney4c051412013-08-08 17:27:19 -040084 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
Jeff Mahoney6c176752009-03-30 14:02:34 -040085 error = dir->i_op->unlink(dir, dentry);
86 mutex_unlock(&dentry->d_inode->i_mutex);
87
88 if (!error)
89 d_delete(dentry);
90 return error;
91}
92
93static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
94{
95 int error;
96 BUG_ON(!mutex_is_locked(&dir->i_mutex));
Jeff Mahoney6c176752009-03-30 14:02:34 -040097
Jeff Mahoney4c051412013-08-08 17:27:19 -040098 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
Jeff Mahoney6c176752009-03-30 14:02:34 -040099 error = dir->i_op->rmdir(dir, dentry);
100 if (!error)
101 dentry->d_inode->i_flags |= S_DEAD;
102 mutex_unlock(&dentry->d_inode->i_mutex);
103 if (!error)
104 d_delete(dentry);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400105
106 return error;
107}
108
Jeff Mahoney6c176752009-03-30 14:02:34 -0400109#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
110
Jeff Mahoney6c176752009-03-30 14:02:34 -0400111static struct dentry *open_xa_root(struct super_block *sb, int flags)
112{
113 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400114 struct dentry *xaroot;
115 if (!privroot->d_inode)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400116 return ERR_PTR(-ENODATA);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400117
118 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
119
120 xaroot = dget(REISERFS_SB(sb)->xattr_root);
Jeff Mahoneyceb5edc2009-05-17 01:02:02 -0400121 if (!xaroot)
122 xaroot = ERR_PTR(-ENODATA);
123 else if (!xaroot->d_inode) {
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400124 int err = -ENODATA;
125 if (xattr_may_create(flags))
126 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
127 if (err) {
128 dput(xaroot);
129 xaroot = ERR_PTR(err);
130 }
131 }
132
133 mutex_unlock(&privroot->d_inode->i_mutex);
134 return xaroot;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400135}
136
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700137static struct dentry *open_xa_dir(const struct inode *inode, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700139 struct dentry *xaroot, *xadir;
140 char namebuf[17];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
Jeff Mahoney6c176752009-03-30 14:02:34 -0400142 xaroot = open_xa_root(inode->i_sb, flags);
Jeff Mahoney9b7f3752007-04-23 14:41:17 -0700143 if (IS_ERR(xaroot))
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700144 return xaroot;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700146 snprintf(namebuf, sizeof(namebuf), "%X.%X",
147 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
148 inode->i_generation);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400150 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
151
152 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
153 if (!IS_ERR(xadir) && !xadir->d_inode) {
154 int err = -ENODATA;
155 if (xattr_may_create(flags))
156 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
157 if (err) {
158 dput(xadir);
159 xadir = ERR_PTR(err);
160 }
161 }
162
163 mutex_unlock(&xaroot->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700164 dput(xaroot);
165 return xadir;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166}
167
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400168/* The following are side effects of other operations that aren't explicitly
169 * modifying extended attributes. This includes operations such as permissions
170 * or ownership changes, object deletions, etc. */
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400171struct reiserfs_dentry_buf {
Al Viro4acf3812013-05-17 22:42:17 -0400172 struct dir_context ctx;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400173 struct dentry *xadir;
174 int count;
175 struct dentry *dentries[8];
176};
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400177
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400178static int
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400179fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
180 u64 ino, unsigned int d_type)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400181{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400182 struct reiserfs_dentry_buf *dbuf = buf;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400183 struct dentry *dentry;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400184 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400185
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400186 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
187 return -ENOSPC;
188
Jan Kara35e5cbc2013-03-29 15:39:16 +0100189 if (name[0] == '.' && (namelen < 2 ||
190 (namelen == 2 && name[1] == '.')))
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400191 return 0;
192
193 dentry = lookup_one_len(name, dbuf->xadir, namelen);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400194 if (IS_ERR(dentry)) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400195 return PTR_ERR(dentry);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400196 } else if (!dentry->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400197 /* A directory entry exists, but no file? */
198 reiserfs_error(dentry->d_sb, "xattr-20003",
199 "Corrupted directory: xattr %s listed but "
200 "not found for file %s.\n",
201 dentry->d_name.name, dbuf->xadir->d_name.name);
202 dput(dentry);
203 return -EIO;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400204 }
205
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400206 dbuf->dentries[dbuf->count++] = dentry;
207 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400208}
209
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400210static void
211cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400212{
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400213 int i;
214 for (i = 0; i < buf->count; i++)
215 if (buf->dentries[i])
216 dput(buf->dentries[i]);
217}
218
219static int reiserfs_for_each_xattr(struct inode *inode,
220 int (*action)(struct dentry *, void *),
221 void *data)
222{
223 struct dentry *dir;
224 int i, err = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400225 struct reiserfs_dentry_buf buf = {
Al Viro4acf3812013-05-17 22:42:17 -0400226 .ctx.actor = fill_with_dentries,
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400227 };
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400228
229 /* Skip out, an xattr has no xattrs associated with it */
230 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
231 return 0;
232
Jeff Mahoney6c176752009-03-30 14:02:34 -0400233 dir = open_xa_dir(inode, XATTR_REPLACE);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400234 if (IS_ERR(dir)) {
235 err = PTR_ERR(dir);
236 goto out;
237 } else if (!dir->d_inode) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400238 err = 0;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400239 goto out_dir;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400240 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400241
Jeff Mahoney6c176752009-03-30 14:02:34 -0400242 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Frederic Weisbecker27026a02009-12-30 05:06:21 +0100243
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400244 buf.xadir = dir;
Al Virocd62cda2013-05-17 22:58:58 -0400245 while (1) {
246 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
247 if (err)
248 break;
249 if (!buf.count)
250 break;
251 for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400252 struct dentry *dentry = buf.dentries[i];
253
Al Virocd62cda2013-05-17 22:58:58 -0400254 if (!S_ISDIR(dentry->d_inode->i_mode))
255 err = action(dentry, data);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400256
257 dput(dentry);
258 buf.dentries[i] = NULL;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400259 }
Al Virocd62cda2013-05-17 22:58:58 -0400260 if (err)
261 break;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400262 buf.count = 0;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400263 }
Jeff Mahoney6c176752009-03-30 14:02:34 -0400264 mutex_unlock(&dir->d_inode->i_mutex);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400265
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400266 cleanup_dentry_buf(&buf);
267
268 if (!err) {
269 /* We start a transaction here to avoid a ABBA situation
270 * between the xattr root's i_mutex and the journal lock.
271 * This doesn't incur much additional overhead since the
272 * new transaction will just nest inside the
273 * outer transaction. */
274 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
275 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
276 struct reiserfs_transaction_handle th;
Jeff Mahoney4c051412013-08-08 17:27:19 -0400277 reiserfs_write_lock(inode->i_sb);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400278 err = journal_begin(&th, inode->i_sb, blocks);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400279 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400280 if (!err) {
281 int jerror;
Jeff Mahoney4c051412013-08-08 17:27:19 -0400282 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
283 I_MUTEX_XATTR);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400284 err = action(dir, data);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400285 reiserfs_write_lock(inode->i_sb);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400286 jerror = journal_end(&th, inode->i_sb, blocks);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400287 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400288 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
289 err = jerror ?: err;
290 }
291 }
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400292out_dir:
293 dput(dir);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400294out:
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400295 /* -ENODATA isn't an error */
296 if (err == -ENODATA)
297 err = 0;
298 return err;
299}
300
301static int delete_one_xattr(struct dentry *dentry, void *data)
302{
303 struct inode *dir = dentry->d_parent->d_inode;
304
305 /* This is the xattr dir, handle specially. */
306 if (S_ISDIR(dentry->d_inode->i_mode))
307 return xattr_rmdir(dir, dentry);
308
309 return xattr_unlink(dir, dentry);
310}
311
312static int chown_one_xattr(struct dentry *dentry, void *data)
313{
314 struct iattr *attrs = data;
Jeff Mahoney4a857012013-05-31 15:54:17 -0400315 int ia_valid = attrs->ia_valid;
316 int err;
317
318 /*
319 * We only want the ownership bits. Otherwise, we'll do
320 * things like change a directory to a regular file if
321 * ATTR_MODE is set.
322 */
323 attrs->ia_valid &= (ATTR_UID|ATTR_GID);
324 err = reiserfs_setattr(dentry, attrs);
325 attrs->ia_valid = ia_valid;
326
327 return err;
Jeff Mahoneya41f1a42009-03-30 14:02:40 -0400328}
329
330/* No i_mutex, but the inode is unconnected. */
331int reiserfs_delete_xattrs(struct inode *inode)
332{
333 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
334 if (err)
335 reiserfs_warning(inode->i_sb, "jdm-20004",
336 "Couldn't delete all xattrs (%d)\n", err);
337 return err;
338}
339
340/* inode->i_mutex: down */
341int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
342{
343 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400344 if (err)
345 reiserfs_warning(inode->i_sb, "jdm-20007",
346 "Couldn't chown all xattrs (%d)\n", err);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400347 return err;
348}
349
350#ifdef CONFIG_REISERFS_FS_XATTR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351/* Returns a dentry corresponding to a specific extended attribute file
352 * for the inode. If flags allow, the file is created. Otherwise, a
353 * valid or negative dentry, or an error is returned. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400354static struct dentry *xattr_lookup(struct inode *inode, const char *name,
355 int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700357 struct dentry *xadir, *xafile;
358 int err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700360 xadir = open_xa_dir(inode, flags);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400361 if (IS_ERR(xadir))
David Howellse231c2e2008-02-07 00:15:26 -0800362 return ERR_CAST(xadir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400364 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700365 xafile = lookup_one_len(name, xadir, strlen(name));
366 if (IS_ERR(xafile)) {
Jeff Mahoney6c176752009-03-30 14:02:34 -0400367 err = PTR_ERR(xafile);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700368 goto out;
Jeff Mahoney6c176752009-03-30 14:02:34 -0400369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
Jeff Mahoney6c176752009-03-30 14:02:34 -0400371 if (xafile->d_inode && (flags & XATTR_CREATE))
372 err = -EEXIST;
373
374 if (!xafile->d_inode) {
375 err = -ENODATA;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400376 if (xattr_may_create(flags))
Jeff Mahoney6c176752009-03-30 14:02:34 -0400377 err = xattr_create(xadir->d_inode, xafile,
378 0700|S_IFREG);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700379 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380
Jeff Mahoney6c176752009-03-30 14:02:34 -0400381 if (err)
382 dput(xafile);
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400383out:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400384 mutex_unlock(&xadir->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700385 dput(xadir);
386 if (err)
Jeff Mahoney6c176752009-03-30 14:02:34 -0400387 return ERR_PTR(err);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800388 return xafile;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389}
390
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391/* Internal operations on file data */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700392static inline void reiserfs_put_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700394 kunmap(page);
395 page_cache_release(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396}
397
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400398static struct page *reiserfs_get_page(struct inode *dir, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700400 struct address_space *mapping = dir->i_mapping;
401 struct page *page;
402 /* We can deadlock if we try to free dentries,
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300403 and an unlink/rmdir has just occurred - GFP_NOFS avoids this */
Al Viroc4cdd032005-10-21 03:22:39 -0400404 mapping_set_gfp_mask(mapping, GFP_NOFS);
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400405 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700406 if (!IS_ERR(page)) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700407 kmap(page);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700408 if (PageError(page))
409 goto fail;
410 }
411 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700413 fail:
414 reiserfs_put_page(page);
415 return ERR_PTR(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416}
417
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700418static inline __u32 xattr_hash(const char *msg, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700420 return csum_partial(msg, len, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421}
422
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700423int reiserfs_commit_write(struct file *f, struct page *page,
424 unsigned from, unsigned to);
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700425
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400426static void update_ctime(struct inode *inode)
427{
428 struct timespec now = current_fs_time(inode->i_sb);
Al Viro1d3382cb2010-10-23 15:19:20 -0400429 if (inode_unhashed(inode) || !inode->i_nlink ||
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400430 timespec_equal(&inode->i_ctime, &now))
431 return;
432
433 inode->i_ctime = CURRENT_TIME_SEC;
434 mark_inode_dirty(inode);
435}
436
437static int lookup_and_delete_xattr(struct inode *inode, const char *name)
438{
439 int err = 0;
440 struct dentry *dentry, *xadir;
441
442 xadir = open_xa_dir(inode, XATTR_REPLACE);
443 if (IS_ERR(xadir))
444 return PTR_ERR(xadir);
445
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400446 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400447 dentry = lookup_one_len(name, xadir, strlen(name));
448 if (IS_ERR(dentry)) {
449 err = PTR_ERR(dentry);
450 goto out_dput;
451 }
452
453 if (dentry->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400454 err = xattr_unlink(xadir->d_inode, dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400455 update_ctime(inode);
456 }
457
458 dput(dentry);
459out_dput:
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400460 mutex_unlock(&xadir->d_inode->i_mutex);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400461 dput(xadir);
462 return err;
463}
464
Vladimir Savelievba9d8ce2007-10-16 01:25:14 -0700465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466/* Generic extended attribute operations that can be used by xa plugins */
467
468/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800469 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 */
471int
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400472reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
473 struct inode *inode, const char *name,
474 const void *buffer, size_t buffer_size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700476 int err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800477 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700478 struct page *page;
479 char *data;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700480 size_t file_pos = 0;
481 size_t buffer_pos = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400482 size_t new_size;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700483 __u32 xahash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700485 if (get_inode_sd_version(inode) == STAT_DATA_V1)
486 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
Frederic Weisbecker4f3be1b2010-01-05 02:14:30 +0100488 if (!buffer) {
489 err = lookup_and_delete_xattr(inode, name);
Frederic Weisbecker4f3be1b2010-01-05 02:14:30 +0100490 return err;
491 }
492
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400493 dentry = xattr_lookup(inode, name, flags);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400494 if (IS_ERR(dentry))
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400495 return PTR_ERR(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496
Frederic Weisbeckerf3e22f42010-01-03 03:44:53 +0100497 down_write(&REISERFS_I(inode)->i_xattr_sem);
Frederic Weisbecker3f14fea2009-12-30 07:03:53 +0100498
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 Mahoney4c051412013-08-08 17:27:19 -0400528 reiserfs_write_lock(inode->i_sb);
Christoph Hellwigebdec242010-10-06 10:47:23 +0200529 err = __reiserfs_write_begin(page, 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 }
Jeff Mahoney4c051412013-08-08 17:27:19 -0400537 reiserfs_write_unlock(inode->i_sb);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700538 unlock_page(page);
539 reiserfs_put_page(page);
540 buffer_pos += chunk;
541 file_pos += chunk;
542 skip = 0;
543 if (err || buffer_size == 0 || !buffer)
544 break;
545 }
546
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400547 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
548 if (!err && new_size < i_size_read(dentry->d_inode)) {
549 struct iattr newattrs = {
550 .ia_ctime = current_fs_time(inode->i_sb),
Jeff Mahoneyfb2162d2010-04-23 13:17:41 -0400551 .ia_size = new_size,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400552 .ia_valid = ATTR_SIZE | ATTR_CTIME,
553 };
Frederic Weisbecker31370f62010-01-07 15:55:31 +0100554
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400555 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
Christoph Hellwigbd5fe6c2011-06-24 14:29:43 -0400556 inode_dio_wait(dentry->d_inode);
Frederic Weisbecker31370f62010-01-07 15:55:31 +0100557
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400558 err = reiserfs_setattr(dentry, &newattrs);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400559 mutex_unlock(&dentry->d_inode->i_mutex);
560 } else
561 update_ctime(inode);
562out_unlock:
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400563 up_write(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800564 dput(dentry);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400565 return err;
566}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700567
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400568/* We need to start a transaction to maintain lock ordering */
569int reiserfs_xattr_set(struct inode *inode, const char *name,
570 const void *buffer, size_t buffer_size, int flags)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400571{
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400572
573 struct reiserfs_transaction_handle th;
574 int error, error2;
575 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
576
577 if (!(flags & XATTR_REPLACE))
578 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
579
580 reiserfs_write_lock(inode->i_sb);
581 error = journal_begin(&th, inode->i_sb, jbegin_count);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400582 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400583 if (error) {
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400584 return error;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700585 }
586
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400587 error = reiserfs_xattr_set_handle(&th, inode, name,
588 buffer, buffer_size, flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700589
Jeff Mahoney4c051412013-08-08 17:27:19 -0400590 reiserfs_write_lock(inode->i_sb);
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400591 error2 = journal_end(&th, inode->i_sb, jbegin_count);
Jeff Mahoney4c051412013-08-08 17:27:19 -0400592 reiserfs_write_unlock(inode->i_sb);
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400593 if (error == 0)
594 error = error2;
Jeff Mahoney0ab26212009-03-30 14:02:39 -0400595
596 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597}
598
599/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800600 * inode->i_mutex: down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 */
602int
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400603reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700604 size_t buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700606 ssize_t err = 0;
Jeff Mahoney3227e142008-02-15 14:37:22 -0800607 struct dentry *dentry;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700608 size_t isize;
609 size_t file_pos = 0;
610 size_t buffer_pos = 0;
611 struct page *page;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700612 __u32 hash = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700614 if (name == NULL)
615 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700617 /* We can't have xattrs attached to v1 items since they don't have
618 * generation numbers */
619 if (get_inode_sd_version(inode) == STAT_DATA_V1)
620 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400622 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800623 if (IS_ERR(dentry)) {
624 err = PTR_ERR(dentry);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700625 goto out;
626 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400628 down_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoneyd9845612009-03-30 14:02:35 -0400629
Jeff Mahoneyf437c522009-03-30 14:02:29 -0400630 isize = i_size_read(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700632 /* Just return the size needed */
633 if (buffer == NULL) {
634 err = isize - sizeof(struct reiserfs_xattr_header);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400635 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700636 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700638 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
639 err = -ERANGE;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400640 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700641 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700643 while (file_pos < isize) {
644 size_t chunk;
645 char *data;
646 size_t skip = 0;
647 if (isize - file_pos > PAGE_CACHE_SIZE)
648 chunk = PAGE_CACHE_SIZE;
649 else
650 chunk = isize - file_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651
Jeff Mahoneyec6ea562009-03-30 14:02:30 -0400652 page = reiserfs_get_page(dentry->d_inode, file_pos);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700653 if (IS_ERR(page)) {
654 err = PTR_ERR(page);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400655 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700656 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700658 lock_page(page);
659 data = page_address(page);
660 if (file_pos == 0) {
661 struct reiserfs_xattr_header *rxh =
662 (struct reiserfs_xattr_header *)data;
663 skip = file_pos = sizeof(struct reiserfs_xattr_header);
664 chunk -= skip;
665 /* Magic doesn't match up.. */
666 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
667 unlock_page(page);
668 reiserfs_put_page(page);
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400669 reiserfs_warning(inode->i_sb, "jdm-20001",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700670 "Invalid magic for xattr (%s) "
671 "associated with %k", name,
672 INODE_PKEY(inode));
673 err = -EIO;
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400674 goto out_unlock;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700675 }
676 hash = le32_to_cpu(rxh->h_hash);
677 }
678 memcpy(buffer + buffer_pos, data + skip, chunk);
679 unlock_page(page);
680 reiserfs_put_page(page);
681 file_pos += chunk;
682 buffer_pos += chunk;
683 skip = 0;
684 }
685 err = isize - sizeof(struct reiserfs_xattr_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700687 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
688 hash) {
Jeff Mahoney45b03d52009-03-30 14:02:21 -0400689 reiserfs_warning(inode->i_sb, "jdm-20002",
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700690 "Invalid hash for xattr (%s) associated "
691 "with %k", name, INODE_PKEY(inode));
692 err = -EIO;
693 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400695out_unlock:
696 up_read(&REISERFS_I(inode)->i_xattr_sem);
Jeff Mahoney3227e142008-02-15 14:37:22 -0800697 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400699out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700700 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701}
702
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400703/*
704 * In order to implement different sets of xattr operations for each xattr
705 * prefix with the generic xattr API, a filesystem should create a
706 * null-terminated array of struct xattr_handler (one for each prefix) and
707 * hang a pointer to it off of the s_xattr field of the superblock.
708 *
709 * The generic_fooxattr() functions will use this list to dispatch xattr
710 * operations to the correct xattr_handler.
711 */
712#define for_each_xattr_handler(handlers, handler) \
713 for ((handler) = *(handlers)++; \
714 (handler) != NULL; \
715 (handler) = *(handlers)++)
716
717/* This is the implementation for the xattr plugin infrastructure */
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700718static inline const struct xattr_handler *
719find_xattr_handler_prefix(const struct xattr_handler **handlers,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400720 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700722 const struct xattr_handler *xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400724 if (!handlers)
725 return NULL;
726
727 for_each_xattr_handler(handlers, xah) {
728 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
729 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 }
731
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400732 return xah;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733}
734
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
736/*
737 * Inode operation getxattr()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 */
739ssize_t
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700740reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
741 size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700743 const struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744
Christoph Hellwig431547b2009-11-13 09:52:56 +0000745 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400746
Christoph Hellwig431547b2009-11-13 09:52:56 +0000747 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700748 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
Christoph Hellwig431547b2009-11-13 09:52:56 +0000750 return handler->get(dentry, name, buffer, size, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751}
752
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753/*
754 * Inode operation setxattr()
755 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800756 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 */
758int
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700759reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
760 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700762 const struct xattr_handler *handler;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763
Christoph Hellwig431547b2009-11-13 09:52:56 +0000764 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400765
Christoph Hellwig431547b2009-11-13 09:52:56 +0000766 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700767 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768
Christoph Hellwig431547b2009-11-13 09:52:56 +0000769 return handler->set(dentry, name, value, size, flags, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770}
771
772/*
773 * Inode operation removexattr()
774 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800775 * dentry->d_inode->i_mutex down
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700777int reiserfs_removexattr(struct dentry *dentry, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778{
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700779 const struct xattr_handler *handler;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000780 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
Christoph Hellwig431547b2009-11-13 09:52:56 +0000782 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700783 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784
Christoph Hellwig431547b2009-11-13 09:52:56 +0000785 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786}
787
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400788struct listxattr_buf {
Al Viro4acf3812013-05-17 22:42:17 -0400789 struct dir_context ctx;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400790 size_t size;
791 size_t pos;
792 char *buf;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000793 struct dentry *dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794};
795
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400796static int listxattr_filler(void *buf, const char *name, int namelen,
797 loff_t offset, u64 ino, unsigned int d_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798{
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400799 struct listxattr_buf *b = (struct listxattr_buf *)buf;
800 size_t size;
801 if (name[0] != '.' ||
802 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
Stephen Hemminger94d09a92010-05-13 17:53:19 -0700803 const struct xattr_handler *handler;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000804 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400805 name);
806 if (!handler) /* Unsupported xattr name */
807 return 0;
808 if (b->buf) {
Christoph Hellwig431547b2009-11-13 09:52:56 +0000809 size = handler->list(b->dentry, b->buf + b->pos,
810 b->size, name, namelen,
811 handler->flags);
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400812 if (size > b->size)
813 return -ERANGE;
814 } else {
Christoph Hellwig431547b2009-11-13 09:52:56 +0000815 size = handler->list(b->dentry, NULL, 0, name,
816 namelen, handler->flags);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700817 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400819 b->pos += size;
820 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700821 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822}
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700823
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824/*
825 * Inode operation listxattr()
826 *
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400827 * We totally ignore the generic listxattr here because it would be stupid
828 * not to. Since the xattrs are organized in a directory, we can just
829 * readdir to find them.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700831ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700833 struct dentry *dir;
834 int err = 0;
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400835 struct listxattr_buf buf = {
Al Viro4acf3812013-05-17 22:42:17 -0400836 .ctx.actor = listxattr_filler,
Christoph Hellwig431547b2009-11-13 09:52:56 +0000837 .dentry = dentry,
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400838 .buf = buffer,
839 .size = buffer ? size : 0,
840 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700842 if (!dentry->d_inode)
843 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844
Jeff Mahoney677c9b22009-05-05 15:30:17 -0400845 if (!dentry->d_sb->s_xattr ||
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700846 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
847 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
Jeff Mahoney6c176752009-03-30 14:02:34 -0400849 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700850 if (IS_ERR(dir)) {
851 err = PTR_ERR(dir);
852 if (err == -ENODATA)
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400853 err = 0; /* Not an error if there aren't any xattrs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700854 goto out;
855 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856
Jeff Mahoney6c176752009-03-30 14:02:34 -0400857 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
Al Virocd62cda2013-05-17 22:58:58 -0400858 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
Jeff Mahoney6c176752009-03-30 14:02:34 -0400859 mutex_unlock(&dir->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400861 if (!err)
862 err = buf.pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863
Jeff Mahoney3227e142008-02-15 14:37:22 -0800864 dput(dir);
Jeff Mahoney8b6dd722009-03-30 14:02:36 -0400865out:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700866 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867}
868
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400869static int create_privroot(struct dentry *dentry)
870{
871 int err;
872 struct inode *inode = dentry->d_parent->d_inode;
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400873 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
874
Jeff Mahoney6c176752009-03-30 14:02:34 -0400875 err = xattr_mkdir(inode, dentry, 0700);
Al Viroedcc37a2009-05-03 06:00:05 -0400876 if (err || !dentry->d_inode) {
877 reiserfs_warning(dentry->d_sb, "jdm-20006",
878 "xattrs/ACLs enabled and couldn't "
879 "find/create .reiserfs_priv. "
880 "Failing mount.");
881 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700882 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883
Al Viroedcc37a2009-05-03 06:00:05 -0400884 dentry->d_inode->i_flags |= S_PRIVATE;
885 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
886 "storage.\n", PRIVROOT_NAME);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887
Al Viroedcc37a2009-05-03 06:00:05 -0400888 return 0;
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400889}
890
Jeff Mahoney12abb352009-05-17 01:02:01 -0400891#else
892int __init reiserfs_xattr_register_handlers(void) { return 0; }
893void reiserfs_xattr_unregister_handlers(void) {}
894static int create_privroot(struct dentry *dentry) { return 0; }
895#endif
896
897/* Actual operations that are exported to VFS-land */
Sachin Kamatda02eb72012-08-23 17:28:57 +0200898static const struct xattr_handler *reiserfs_xattr_handlers[] = {
Jeff Mahoney12abb352009-05-17 01:02:01 -0400899#ifdef CONFIG_REISERFS_FS_XATTR
900 &reiserfs_xattr_user_handler,
901 &reiserfs_xattr_trusted_handler,
902#endif
903#ifdef CONFIG_REISERFS_FS_SECURITY
904 &reiserfs_xattr_security_handler,
905#endif
906#ifdef CONFIG_REISERFS_FS_POSIX_ACL
907 &reiserfs_posix_acl_access_handler,
908 &reiserfs_posix_acl_default_handler,
909#endif
910 NULL
911};
912
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400913static int xattr_mount_check(struct super_block *s)
914{
915 /* We need generation numbers to ensure that the oid mapping is correct
916 * v3.5 filesystems don't have them. */
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400917 if (old_format_only(s)) {
918 if (reiserfs_xattrs_optional(s)) {
919 /* Old format filesystem, but optional xattrs have
920 * been enabled. Error out. */
921 reiserfs_warning(s, "jdm-2005",
922 "xattrs/ACLs not supported "
923 "on pre-v3.6 format filesystems. "
924 "Failing mount.");
925 return -EOPNOTSUPP;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700926 }
927 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400929 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930}
931
Al Viro10556cb2011-06-20 19:28:19 -0400932int reiserfs_permission(struct inode *inode, int mask)
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400933{
934 /*
935 * We don't do permission checks on the internal objects.
936 * Permissions are determined by the "owning" object.
937 */
938 if (IS_PRIVATE(inode))
939 return 0;
940
Al Viro2830ba72011-06-20 19:16:29 -0400941 return generic_permission(inode, mask);
Jeff Mahoneyb83674c2009-05-17 01:02:03 -0400942}
943
Al Viro0b728e12012-06-10 16:03:43 -0400944static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945{
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400946 return -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947}
948
Al Viroe16404e2009-02-20 05:55:13 +0000949static const struct dentry_operations xattr_lookup_poison_ops = {
Jeff Mahoneycac36f72010-04-23 13:17:37 -0400950 .d_revalidate = xattr_hide_revalidate,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951};
952
Al Viroedcc37a2009-05-03 06:00:05 -0400953int reiserfs_lookup_privroot(struct super_block *s)
954{
955 struct dentry *dentry;
956 int err = 0;
957
958 /* If we don't have the privroot located yet - go find it */
Jeff Mahoney4c051412013-08-08 17:27:19 -0400959 mutex_lock(&s->s_root->d_inode->i_mutex);
Al Viroedcc37a2009-05-03 06:00:05 -0400960 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
961 strlen(PRIVROOT_NAME));
962 if (!IS_ERR(dentry)) {
963 REISERFS_SB(s)->priv_root = dentry;
Nick Pigginfb045ad2011-01-07 17:49:55 +1100964 d_set_d_op(dentry, &xattr_lookup_poison_ops);
Al Viroedcc37a2009-05-03 06:00:05 -0400965 if (dentry->d_inode)
966 dentry->d_inode->i_flags |= S_PRIVATE;
967 } else
968 err = PTR_ERR(dentry);
969 mutex_unlock(&s->s_root->d_inode->i_mutex);
970
971 return err;
972}
973
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974/* We need to take a copy of the mount flags since things like
975 * MS_RDONLY don't get set until *after* we're called.
976 * mount_flags != mount_options */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700977int reiserfs_xattr_init(struct super_block *s, int mount_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700979 int err = 0;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400980 struct dentry *privroot = REISERFS_SB(s)->priv_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981
Jeff Mahoneya72bdb12009-03-30 14:02:33 -0400982 err = xattr_mount_check(s);
983 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700984 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400986 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
Jeff Mahoney4c051412013-08-08 17:27:19 -0400987 mutex_lock(&s->s_root->d_inode->i_mutex);
Al Viroedcc37a2009-05-03 06:00:05 -0400988 err = create_privroot(REISERFS_SB(s)->priv_root);
Jeff Mahoney5a6059c2009-05-01 12:11:12 -0400989 mutex_unlock(&s->s_root->d_inode->i_mutex);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700990 }
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400991
992 if (privroot->d_inode) {
Jeff Mahoney48b32a32009-03-30 14:02:38 -0400993 s->s_xattr = reiserfs_xattr_handlers;
Jeff Mahoney4c051412013-08-08 17:27:19 -0400994 mutex_lock(&privroot->d_inode->i_mutex);
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -0400995 if (!REISERFS_SB(s)->xattr_root) {
996 struct dentry *dentry;
997 dentry = lookup_one_len(XAROOT_NAME, privroot,
998 strlen(XAROOT_NAME));
999 if (!IS_ERR(dentry))
1000 REISERFS_SB(s)->xattr_root = dentry;
1001 else
1002 err = PTR_ERR(dentry);
1003 }
1004 mutex_unlock(&privroot->d_inode->i_mutex);
1005 }
Jeff Mahoney48b32a32009-03-30 14:02:38 -04001006
Jeff Mahoneya72bdb12009-03-30 14:02:33 -04001007error:
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001008 if (err) {
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001009 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1010 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1011 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001013 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001014 if (reiserfs_posixacl(s))
1015 s->s_flags |= MS_POSIXACL;
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001016 else
Jeff Mahoneyab17c4f2009-05-05 15:30:15 -04001017 s->s_flags &= ~MS_POSIXACL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07001019 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020}