2 * linux/fs/reiserfs/xattr.c
4 * Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com>
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.
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
23 * The file contents are the text of the EA. The size is known based on the
24 * stat data describing the file.
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.
31 * Locking works like so:
32 * Directory components (xattr root, xattr dir) are protectd by their i_mutex.
33 * The xattrs themselves are protected by the xattr_sem.
36 #include <linux/reiserfs_fs.h>
37 #include <linux/capability.h>
38 #include <linux/dcache.h>
39 #include <linux/namei.h>
40 #include <linux/errno.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>
47 #include <asm/uaccess.h>
48 #include <net/checksum.h>
49 #include <linux/stat.h>
50 #include <linux/quotaops.h>
51 #include <linux/security.h>
53 #define PRIVROOT_NAME ".reiserfs_priv"
54 #define XAROOT_NAME "xattrs"
57 /* 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. */
60 #ifdef CONFIG_REISERFS_FS_XATTR
61 static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
63 BUG_ON(!mutex_is_locked(&dir->i_mutex));
65 return dir->i_op->create(dir, dentry, mode, NULL);
69 static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode)
71 BUG_ON(!mutex_is_locked(&dir->i_mutex));
73 return dir->i_op->mkdir(dir, dentry, mode);
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. */
80 static int xattr_unlink(struct inode *dir, struct dentry *dentry)
83 BUG_ON(!mutex_is_locked(&dir->i_mutex));
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);
95 static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
98 BUG_ON(!mutex_is_locked(&dir->i_mutex));
101 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
102 dentry_unhash(dentry);
103 error = dir->i_op->rmdir(dir, dentry);
105 dentry->d_inode->i_flags |= S_DEAD;
106 mutex_unlock(&dentry->d_inode->i_mutex);
114 #define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
116 static struct dentry *open_xa_root(struct super_block *sb, int flags)
118 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
119 struct dentry *xaroot;
120 if (!privroot->d_inode)
121 return ERR_PTR(-ENODATA);
123 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
125 xaroot = dget(REISERFS_SB(sb)->xattr_root);
127 xaroot = ERR_PTR(-ENODATA);
128 else if (!xaroot->d_inode) {
130 if (xattr_may_create(flags))
131 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
134 xaroot = ERR_PTR(err);
138 mutex_unlock(&privroot->d_inode->i_mutex);
142 static struct dentry *open_xa_dir(const struct inode *inode, int flags)
144 struct dentry *xaroot, *xadir;
147 xaroot = open_xa_root(inode->i_sb, flags);
151 snprintf(namebuf, sizeof(namebuf), "%X.%X",
152 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
153 inode->i_generation);
155 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
157 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
158 if (!IS_ERR(xadir) && !xadir->d_inode) {
160 if (xattr_may_create(flags))
161 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
164 xadir = ERR_PTR(err);
168 mutex_unlock(&xaroot->d_inode->i_mutex);
173 /* 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. */
176 struct reiserfs_dentry_buf {
177 struct dentry *xadir;
179 struct dentry *dentries[8];
183 fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
184 u64 ino, unsigned int d_type)
186 struct reiserfs_dentry_buf *dbuf = buf;
187 struct dentry *dentry;
188 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
190 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
193 if (name[0] == '.' && (name[1] == '\0' ||
194 (name[1] == '.' && name[2] == '\0')))
197 dentry = lookup_one_len(name, dbuf->xadir, namelen);
198 if (IS_ERR(dentry)) {
199 return PTR_ERR(dentry);
200 } else if (!dentry->d_inode) {
201 /* 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);
210 dbuf->dentries[dbuf->count++] = dentry;
215 cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
218 for (i = 0; i < buf->count; i++)
219 if (buf->dentries[i])
220 dput(buf->dentries[i]);
223 static int reiserfs_for_each_xattr(struct inode *inode,
224 int (*action)(struct dentry *, void *),
230 struct reiserfs_dentry_buf buf = {
234 /* Skip out, an xattr has no xattrs associated with it */
235 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
238 dir = open_xa_dir(inode, XATTR_REPLACE);
242 } else if (!dir->d_inode) {
247 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
249 err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
250 while ((err == 0 || err == -ENOSPC) && buf.count) {
253 for (i = 0; i < buf.count && buf.dentries[i]; i++) {
255 struct dentry *dentry = buf.dentries[i];
257 if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
258 lerr = action(dentry, data);
261 buf.dentries[i] = NULL;
266 err = reiserfs_readdir_dentry(dir, &buf,
267 fill_with_dentries, &pos);
269 mutex_unlock(&dir->d_inode->i_mutex);
271 /* Clean up after a failed readdir */
272 cleanup_dentry_buf(&buf);
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);
286 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
288 err = action(dir, data);
289 jerror = journal_end(&th, inode->i_sb, blocks);
290 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
297 /* -ENODATA isn't an error */
303 static int delete_one_xattr(struct dentry *dentry, void *data)
305 struct inode *dir = dentry->d_parent->d_inode;
307 /* This is the xattr dir, handle specially. */
308 if (S_ISDIR(dentry->d_inode->i_mode))
309 return xattr_rmdir(dir, dentry);
311 return xattr_unlink(dir, dentry);
314 static int chown_one_xattr(struct dentry *dentry, void *data)
316 struct iattr *attrs = data;
317 return reiserfs_setattr(dentry, attrs);
320 /* No i_mutex, but the inode is unconnected. */
321 int reiserfs_delete_xattrs(struct inode *inode)
323 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
325 reiserfs_warning(inode->i_sb, "jdm-20004",
326 "Couldn't delete all xattrs (%d)\n", err);
330 /* inode->i_mutex: down */
331 int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
333 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
335 reiserfs_warning(inode->i_sb, "jdm-20007",
336 "Couldn't chown all xattrs (%d)\n", err);
340 #ifdef CONFIG_REISERFS_FS_XATTR
341 /* 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. */
344 static struct dentry *xattr_lookup(struct inode *inode, const char *name,
347 struct dentry *xadir, *xafile;
350 xadir = open_xa_dir(inode, flags);
352 return ERR_CAST(xadir);
354 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
355 xafile = lookup_one_len(name, xadir, strlen(name));
356 if (IS_ERR(xafile)) {
357 err = PTR_ERR(xafile);
361 if (xafile->d_inode && (flags & XATTR_CREATE))
364 if (!xafile->d_inode) {
366 if (xattr_may_create(flags))
367 err = xattr_create(xadir->d_inode, xafile,
374 mutex_unlock(&xadir->d_inode->i_mutex);
381 /* Internal operations on file data */
382 static inline void reiserfs_put_page(struct page *page)
385 page_cache_release(page);
388 static struct page *reiserfs_get_page(struct inode *dir, size_t n)
390 struct address_space *mapping = dir->i_mapping;
392 /* We can deadlock if we try to free dentries,
393 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
394 mapping_set_gfp_mask(mapping, GFP_NOFS);
395 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
404 reiserfs_put_page(page);
405 return ERR_PTR(-EIO);
408 static inline __u32 xattr_hash(const char *msg, int len)
410 return csum_partial(msg, len, 0);
413 int reiserfs_commit_write(struct file *f, struct page *page,
414 unsigned from, unsigned to);
415 int reiserfs_prepare_write(struct file *f, struct page *page,
416 unsigned from, unsigned to);
418 static void update_ctime(struct inode *inode)
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))
425 inode->i_ctime = CURRENT_TIME_SEC;
426 mark_inode_dirty(inode);
429 static int lookup_and_delete_xattr(struct inode *inode, const char *name)
432 struct dentry *dentry, *xadir;
434 xadir = open_xa_dir(inode, XATTR_REPLACE);
436 return PTR_ERR(xadir);
438 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
439 dentry = lookup_one_len(name, xadir, strlen(name));
440 if (IS_ERR(dentry)) {
441 err = PTR_ERR(dentry);
445 if (dentry->d_inode) {
446 err = xattr_unlink(xadir->d_inode, dentry);
452 mutex_unlock(&xadir->d_inode->i_mutex);
458 /* Generic extended attribute operations that can be used by xa plugins */
461 * inode->i_mutex: down
464 reiserfs_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)
469 struct dentry *dentry;
473 size_t buffer_pos = 0;
477 if (get_inode_sd_version(inode) == STAT_DATA_V1)
481 return lookup_and_delete_xattr(inode, name);
483 dentry = xattr_lookup(inode, name, flags);
485 return PTR_ERR(dentry);
487 down_write(&REISERFS_I(inode)->i_xattr_sem);
489 xahash = xattr_hash(buffer, buffer_size);
490 while (buffer_pos < buffer_size || buffer_pos == 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;
497 chunk = buffer_size - buffer_pos;
499 page = reiserfs_get_page(dentry->d_inode, file_pos);
506 data = page_address(page);
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);
518 err = reiserfs_prepare_write(NULL, page, page_offset,
519 page_offset + chunk + skip);
522 memcpy(data + skip, buffer + buffer_pos, chunk);
523 err = reiserfs_commit_write(NULL, page, page_offset,
524 page_offset + chunk +
528 reiserfs_put_page(page);
532 if (err || buffer_size == 0 || !buffer)
536 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,
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);
551 up_write(&REISERFS_I(inode)->i_xattr_sem);
556 /* We need to start a transaction to maintain lock ordering */
557 int reiserfs_xattr_set(struct inode *inode, const char *name,
558 const void *buffer, size_t buffer_size, int flags)
561 struct reiserfs_transaction_handle th;
563 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
565 if (!(flags & XATTR_REPLACE))
566 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
568 reiserfs_write_lock(inode->i_sb);
569 error = journal_begin(&th, inode->i_sb, jbegin_count);
571 reiserfs_write_unlock(inode->i_sb);
575 error = reiserfs_xattr_set_handle(&th, inode, name,
576 buffer, buffer_size, flags);
578 error2 = journal_end(&th, inode->i_sb, jbegin_count);
581 reiserfs_write_unlock(inode->i_sb);
587 * inode->i_mutex: down
590 reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
594 struct dentry *dentry;
597 size_t buffer_pos = 0;
604 /* 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)
609 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
610 if (IS_ERR(dentry)) {
611 err = PTR_ERR(dentry);
615 down_read(&REISERFS_I(inode)->i_xattr_sem);
617 isize = i_size_read(dentry->d_inode);
619 /* Just return the size needed */
620 if (buffer == NULL) {
621 err = isize - sizeof(struct reiserfs_xattr_header);
625 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
630 while (file_pos < isize) {
634 if (isize - file_pos > PAGE_CACHE_SIZE)
635 chunk = PAGE_CACHE_SIZE;
637 chunk = isize - file_pos;
639 page = reiserfs_get_page(dentry->d_inode, file_pos);
646 data = page_address(page);
648 struct reiserfs_xattr_header *rxh =
649 (struct reiserfs_xattr_header *)data;
650 skip = file_pos = sizeof(struct reiserfs_xattr_header);
652 /* Magic doesn't match up.. */
653 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
655 reiserfs_put_page(page);
656 reiserfs_warning(inode->i_sb, "jdm-20001",
657 "Invalid magic for xattr (%s) "
658 "associated with %k", name,
663 hash = le32_to_cpu(rxh->h_hash);
665 memcpy(buffer + buffer_pos, data + skip, chunk);
667 reiserfs_put_page(page);
672 err = isize - sizeof(struct reiserfs_xattr_header);
674 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
676 reiserfs_warning(inode->i_sb, "jdm-20002",
677 "Invalid hash for xattr (%s) associated "
678 "with %k", name, INODE_PKEY(inode));
683 up_read(&REISERFS_I(inode)->i_xattr_sem);
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.
696 * The generic_fooxattr() functions will use this list to dispatch xattr
697 * operations to the correct xattr_handler.
699 #define for_each_xattr_handler(handlers, handler) \
700 for ((handler) = *(handlers)++; \
702 (handler) = *(handlers)++)
704 /* This is the implementation for the xattr plugin infrastructure */
705 static inline struct xattr_handler *
706 find_xattr_handler_prefix(struct xattr_handler **handlers,
709 struct xattr_handler *xah;
714 for_each_xattr_handler(handlers, xah) {
715 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
724 * Inode operation getxattr()
727 reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
730 struct xattr_handler *handler;
732 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
734 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
737 return handler->get(dentry, name, buffer, size, handler->flags);
741 * Inode operation setxattr()
743 * dentry->d_inode->i_mutex down
746 reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
747 size_t size, int flags)
749 struct xattr_handler *handler;
751 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
753 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
756 return handler->set(dentry, name, value, size, flags, handler->flags);
760 * Inode operation removexattr()
762 * dentry->d_inode->i_mutex down
764 int reiserfs_removexattr(struct dentry *dentry, const char *name)
766 struct xattr_handler *handler;
767 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
769 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
772 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
775 struct listxattr_buf {
779 struct dentry *dentry;
782 static int listxattr_filler(void *buf, const char *name, int namelen,
783 loff_t offset, u64 ino, unsigned int d_type)
785 struct listxattr_buf *b = (struct listxattr_buf *)buf;
787 if (name[0] != '.' ||
788 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
789 struct xattr_handler *handler;
790 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
792 if (!handler) /* Unsupported xattr name */
795 size = handler->list(b->dentry, b->buf + b->pos,
796 b->size, name, namelen,
801 size = handler->list(b->dentry, NULL, 0, name,
802 namelen, handler->flags);
811 * Inode operation listxattr()
813 * We totally ignore the generic listxattr here because it would be stupid
814 * not to. Since the xattrs are organized in a directory, we can just
815 * readdir to find them.
817 ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
822 struct listxattr_buf buf = {
825 .size = buffer ? size : 0,
828 if (!dentry->d_inode)
831 if (!dentry->d_sb->s_xattr ||
832 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
835 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
839 err = 0; /* Not an error if there aren't any xattrs */
843 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
844 err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
845 mutex_unlock(&dir->d_inode->i_mutex);
855 static int reiserfs_check_acl(struct inode *inode, int mask)
857 struct posix_acl *acl;
858 int error = -EAGAIN; /* do regular unix permission checks by default */
860 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
864 error = posix_acl_permission(inode, acl, mask);
865 posix_acl_release(acl);
866 } else if (PTR_ERR(acl) != -ENODATA)
867 error = PTR_ERR(acl);
873 static int create_privroot(struct dentry *dentry)
876 struct inode *inode = dentry->d_parent->d_inode;
877 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
879 err = xattr_mkdir(inode, dentry, 0700);
880 if (err || !dentry->d_inode) {
881 reiserfs_warning(dentry->d_sb, "jdm-20006",
882 "xattrs/ACLs enabled and couldn't "
883 "find/create .reiserfs_priv. "
888 dentry->d_inode->i_flags |= S_PRIVATE;
889 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
890 "storage.\n", PRIVROOT_NAME);
896 int __init reiserfs_xattr_register_handlers(void) { return 0; }
897 void reiserfs_xattr_unregister_handlers(void) {}
898 static int create_privroot(struct dentry *dentry) { return 0; }
901 /* Actual operations that are exported to VFS-land */
902 struct xattr_handler *reiserfs_xattr_handlers[] = {
903 #ifdef CONFIG_REISERFS_FS_XATTR
904 &reiserfs_xattr_user_handler,
905 &reiserfs_xattr_trusted_handler,
907 #ifdef CONFIG_REISERFS_FS_SECURITY
908 &reiserfs_xattr_security_handler,
910 #ifdef CONFIG_REISERFS_FS_POSIX_ACL
911 &reiserfs_posix_acl_access_handler,
912 &reiserfs_posix_acl_default_handler,
917 static int xattr_mount_check(struct super_block *s)
919 /* We need generation numbers to ensure that the oid mapping is correct
920 * v3.5 filesystems don't have them. */
921 if (old_format_only(s)) {
922 if (reiserfs_xattrs_optional(s)) {
923 /* Old format filesystem, but optional xattrs have
924 * been enabled. Error out. */
925 reiserfs_warning(s, "jdm-2005",
926 "xattrs/ACLs not supported "
927 "on pre-v3.6 format filesystems. "
936 int reiserfs_permission(struct inode *inode, int mask)
939 * We don't do permission checks on the internal objects.
940 * Permissions are determined by the "owning" object.
942 if (IS_PRIVATE(inode))
945 #ifdef CONFIG_REISERFS_FS_XATTR
947 * Stat data v1 doesn't support ACLs.
949 if (get_inode_sd_version(inode) != STAT_DATA_V1)
950 return generic_permission(inode, mask, reiserfs_check_acl);
952 return generic_permission(inode, mask, NULL);
955 /* This will catch lookups from the fs root to .reiserfs_priv */
957 xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
959 struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
960 if (container_of(q1, struct dentry, d_name) == priv_root)
962 if (q1->len == name->len &&
963 !memcmp(q1->name, name->name, name->len))
968 static const struct dentry_operations xattr_lookup_poison_ops = {
969 .d_compare = xattr_lookup_poison,
972 int reiserfs_lookup_privroot(struct super_block *s)
974 struct dentry *dentry;
977 /* If we don't have the privroot located yet - go find it */
978 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
979 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
980 strlen(PRIVROOT_NAME));
981 if (!IS_ERR(dentry)) {
982 REISERFS_SB(s)->priv_root = dentry;
983 if (!reiserfs_expose_privroot(s))
984 s->s_root->d_op = &xattr_lookup_poison_ops;
986 dentry->d_inode->i_flags |= S_PRIVATE;
988 err = PTR_ERR(dentry);
989 mutex_unlock(&s->s_root->d_inode->i_mutex);
994 /* 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.
996 * mount_flags != mount_options */
997 int reiserfs_xattr_init(struct super_block *s, int mount_flags)
1000 struct dentry *privroot = REISERFS_SB(s)->priv_root;
1002 err = xattr_mount_check(s);
1006 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
1007 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
1008 err = create_privroot(REISERFS_SB(s)->priv_root);
1009 mutex_unlock(&s->s_root->d_inode->i_mutex);
1012 if (privroot->d_inode) {
1013 s->s_xattr = reiserfs_xattr_handlers;
1014 reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
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;
1022 err = PTR_ERR(dentry);
1024 mutex_unlock(&privroot->d_inode->i_mutex);
1029 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1030 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1033 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
1034 if (reiserfs_posixacl(s))
1035 s->s_flags |= MS_POSIXACL;
1037 s->s_flags &= ~MS_POSIXACL;