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.
37 #include <linux/capability.h>
38 #include <linux/dcache.h>
39 #include <linux/namei.h>
40 #include <linux/errno.h>
41 #include <linux/gfp.h>
43 #include <linux/file.h>
44 #include <linux/pagemap.h>
45 #include <linux/xattr.h>
48 #include <linux/uaccess.h>
49 #include <net/checksum.h>
50 #include <linux/stat.h>
51 #include <linux/quotaops.h>
52 #include <linux/security.h>
53 #include <linux/posix_acl_xattr.h>
55 #define PRIVROOT_NAME ".reiserfs_priv"
56 #define XAROOT_NAME "xattrs"
60 * Helpers for inode ops. We do this so that we don't have all the VFS
61 * overhead and also for proper i_mutex annotation.
62 * dir->i_mutex must be held for all of them.
64 #ifdef CONFIG_REISERFS_FS_XATTR
65 static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
67 BUG_ON(!mutex_is_locked(&dir->i_mutex));
68 return dir->i_op->create(dir, dentry, mode, true);
72 static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
74 BUG_ON(!mutex_is_locked(&dir->i_mutex));
75 return dir->i_op->mkdir(dir, dentry, mode);
79 * We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
80 * mutation ops aren't called during rename or splace, which are the
81 * only other users of I_MUTEX_CHILD. It violates the ordering, but that's
82 * better than allocating another subclass just for this code.
84 static int xattr_unlink(struct inode *dir, struct dentry *dentry)
88 BUG_ON(!mutex_is_locked(&dir->i_mutex));
90 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
91 error = dir->i_op->unlink(dir, dentry);
92 mutex_unlock(&dentry->d_inode->i_mutex);
99 static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
103 BUG_ON(!mutex_is_locked(&dir->i_mutex));
105 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD);
106 error = dir->i_op->rmdir(dir, dentry);
108 dentry->d_inode->i_flags |= S_DEAD;
109 mutex_unlock(&dentry->d_inode->i_mutex);
116 #define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
118 static struct dentry *open_xa_root(struct super_block *sb, int flags)
120 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
121 struct dentry *xaroot;
123 if (!privroot->d_inode)
124 return ERR_PTR(-ENODATA);
126 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
128 xaroot = dget(REISERFS_SB(sb)->xattr_root);
130 xaroot = ERR_PTR(-ENODATA);
131 else if (!xaroot->d_inode) {
134 if (xattr_may_create(flags))
135 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
138 xaroot = ERR_PTR(err);
142 mutex_unlock(&privroot->d_inode->i_mutex);
146 static struct dentry *open_xa_dir(const struct inode *inode, int flags)
148 struct dentry *xaroot, *xadir;
151 xaroot = open_xa_root(inode->i_sb, flags);
155 snprintf(namebuf, sizeof(namebuf), "%X.%X",
156 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
157 inode->i_generation);
159 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
161 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
162 if (!IS_ERR(xadir) && !xadir->d_inode) {
165 if (xattr_may_create(flags))
166 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
169 xadir = ERR_PTR(err);
173 mutex_unlock(&xaroot->d_inode->i_mutex);
179 * The following are side effects of other operations that aren't explicitly
180 * modifying extended attributes. This includes operations such as permissions
181 * or ownership changes, object deletions, etc.
183 struct reiserfs_dentry_buf {
184 struct dir_context ctx;
185 struct dentry *xadir;
187 struct dentry *dentries[8];
191 fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
192 u64 ino, unsigned int d_type)
194 struct reiserfs_dentry_buf *dbuf = buf;
195 struct dentry *dentry;
197 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
199 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
202 if (name[0] == '.' && (namelen < 2 ||
203 (namelen == 2 && name[1] == '.')))
206 dentry = lookup_one_len(name, dbuf->xadir, namelen);
207 if (IS_ERR(dentry)) {
208 return PTR_ERR(dentry);
209 } else if (!dentry->d_inode) {
210 /* A directory entry exists, but no file? */
211 reiserfs_error(dentry->d_sb, "xattr-20003",
212 "Corrupted directory: xattr %s listed but "
213 "not found for file %s.\n",
214 dentry->d_name.name, dbuf->xadir->d_name.name);
219 dbuf->dentries[dbuf->count++] = dentry;
224 cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
228 for (i = 0; i < buf->count; i++)
229 if (buf->dentries[i])
230 dput(buf->dentries[i]);
233 static int reiserfs_for_each_xattr(struct inode *inode,
234 int (*action)(struct dentry *, void *),
239 struct reiserfs_dentry_buf buf = {
240 .ctx.actor = fill_with_dentries,
243 /* Skip out, an xattr has no xattrs associated with it */
244 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
247 dir = open_xa_dir(inode, XATTR_REPLACE);
251 } else if (!dir->d_inode) {
256 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
260 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
265 for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {
266 struct dentry *dentry = buf.dentries[i];
268 if (!S_ISDIR(dentry->d_inode->i_mode))
269 err = action(dentry, data);
272 buf.dentries[i] = NULL;
278 mutex_unlock(&dir->d_inode->i_mutex);
280 cleanup_dentry_buf(&buf);
284 * We start a transaction here to avoid a ABBA situation
285 * between the xattr root's i_mutex and the journal lock.
286 * This doesn't incur much additional overhead since the
287 * new transaction will just nest inside the
290 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
291 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
292 struct reiserfs_transaction_handle th;
294 reiserfs_write_lock(inode->i_sb);
295 err = journal_begin(&th, inode->i_sb, blocks);
296 reiserfs_write_unlock(inode->i_sb);
300 mutex_lock_nested(&dir->d_parent->d_inode->i_mutex,
302 err = action(dir, data);
303 reiserfs_write_lock(inode->i_sb);
304 jerror = journal_end(&th);
305 reiserfs_write_unlock(inode->i_sb);
306 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
313 /* -ENODATA isn't an error */
319 static int delete_one_xattr(struct dentry *dentry, void *data)
321 struct inode *dir = dentry->d_parent->d_inode;
323 /* This is the xattr dir, handle specially. */
324 if (S_ISDIR(dentry->d_inode->i_mode))
325 return xattr_rmdir(dir, dentry);
327 return xattr_unlink(dir, dentry);
330 static int chown_one_xattr(struct dentry *dentry, void *data)
332 struct iattr *attrs = data;
333 int ia_valid = attrs->ia_valid;
337 * We only want the ownership bits. Otherwise, we'll do
338 * things like change a directory to a regular file if
341 attrs->ia_valid &= (ATTR_UID|ATTR_GID);
342 err = reiserfs_setattr(dentry, attrs);
343 attrs->ia_valid = ia_valid;
348 /* No i_mutex, but the inode is unconnected. */
349 int reiserfs_delete_xattrs(struct inode *inode)
351 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
354 reiserfs_warning(inode->i_sb, "jdm-20004",
355 "Couldn't delete all xattrs (%d)\n", err);
359 /* inode->i_mutex: down */
360 int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
362 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
365 reiserfs_warning(inode->i_sb, "jdm-20007",
366 "Couldn't chown all xattrs (%d)\n", err);
370 #ifdef CONFIG_REISERFS_FS_XATTR
372 * Returns a dentry corresponding to a specific extended attribute file
373 * for the inode. If flags allow, the file is created. Otherwise, a
374 * valid or negative dentry, or an error is returned.
376 static struct dentry *xattr_lookup(struct inode *inode, const char *name,
379 struct dentry *xadir, *xafile;
382 xadir = open_xa_dir(inode, flags);
384 return ERR_CAST(xadir);
386 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
387 xafile = lookup_one_len(name, xadir, strlen(name));
388 if (IS_ERR(xafile)) {
389 err = PTR_ERR(xafile);
393 if (xafile->d_inode && (flags & XATTR_CREATE))
396 if (!xafile->d_inode) {
398 if (xattr_may_create(flags))
399 err = xattr_create(xadir->d_inode, xafile,
406 mutex_unlock(&xadir->d_inode->i_mutex);
413 /* Internal operations on file data */
414 static inline void reiserfs_put_page(struct page *page)
417 page_cache_release(page);
420 static struct page *reiserfs_get_page(struct inode *dir, size_t n)
422 struct address_space *mapping = dir->i_mapping;
425 * We can deadlock if we try to free dentries,
426 * and an unlink/rmdir has just occurred - GFP_NOFS avoids this
428 mapping_set_gfp_mask(mapping, GFP_NOFS);
429 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
438 reiserfs_put_page(page);
439 return ERR_PTR(-EIO);
442 static inline __u32 xattr_hash(const char *msg, int len)
444 return csum_partial(msg, len, 0);
447 int reiserfs_commit_write(struct file *f, struct page *page,
448 unsigned from, unsigned to);
450 static void update_ctime(struct inode *inode)
452 struct timespec now = current_fs_time(inode->i_sb);
454 if (inode_unhashed(inode) || !inode->i_nlink ||
455 timespec_equal(&inode->i_ctime, &now))
458 inode->i_ctime = CURRENT_TIME_SEC;
459 mark_inode_dirty(inode);
462 static int lookup_and_delete_xattr(struct inode *inode, const char *name)
465 struct dentry *dentry, *xadir;
467 xadir = open_xa_dir(inode, XATTR_REPLACE);
469 return PTR_ERR(xadir);
471 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
472 dentry = lookup_one_len(name, xadir, strlen(name));
473 if (IS_ERR(dentry)) {
474 err = PTR_ERR(dentry);
478 if (dentry->d_inode) {
479 err = xattr_unlink(xadir->d_inode, dentry);
485 mutex_unlock(&xadir->d_inode->i_mutex);
491 /* Generic extended attribute operations that can be used by xa plugins */
494 * inode->i_mutex: down
497 reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
498 struct inode *inode, const char *name,
499 const void *buffer, size_t buffer_size, int flags)
502 struct dentry *dentry;
506 size_t buffer_pos = 0;
510 if (get_inode_sd_version(inode) == STAT_DATA_V1)
514 err = lookup_and_delete_xattr(inode, name);
518 dentry = xattr_lookup(inode, name, flags);
520 return PTR_ERR(dentry);
522 down_write(&REISERFS_I(inode)->i_xattr_sem);
524 xahash = xattr_hash(buffer, buffer_size);
525 while (buffer_pos < buffer_size || buffer_pos == 0) {
528 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
530 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
531 chunk = PAGE_CACHE_SIZE;
533 chunk = buffer_size - buffer_pos;
535 page = reiserfs_get_page(dentry->d_inode, file_pos);
542 data = page_address(page);
545 struct reiserfs_xattr_header *rxh;
547 skip = file_pos = sizeof(struct reiserfs_xattr_header);
548 if (chunk + skip > PAGE_CACHE_SIZE)
549 chunk = PAGE_CACHE_SIZE - skip;
550 rxh = (struct reiserfs_xattr_header *)data;
551 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
552 rxh->h_hash = cpu_to_le32(xahash);
555 reiserfs_write_lock(inode->i_sb);
556 err = __reiserfs_write_begin(page, page_offset, chunk + skip);
559 memcpy(data + skip, buffer + buffer_pos, chunk);
560 err = reiserfs_commit_write(NULL, page, page_offset,
561 page_offset + chunk +
564 reiserfs_write_unlock(inode->i_sb);
566 reiserfs_put_page(page);
570 if (err || buffer_size == 0 || !buffer)
574 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
575 if (!err && new_size < i_size_read(dentry->d_inode)) {
576 struct iattr newattrs = {
577 .ia_ctime = current_fs_time(inode->i_sb),
579 .ia_valid = ATTR_SIZE | ATTR_CTIME,
582 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
583 inode_dio_wait(dentry->d_inode);
585 err = reiserfs_setattr(dentry, &newattrs);
586 mutex_unlock(&dentry->d_inode->i_mutex);
590 up_write(&REISERFS_I(inode)->i_xattr_sem);
595 /* We need to start a transaction to maintain lock ordering */
596 int reiserfs_xattr_set(struct inode *inode, const char *name,
597 const void *buffer, size_t buffer_size, int flags)
600 struct reiserfs_transaction_handle th;
602 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
604 if (!(flags & XATTR_REPLACE))
605 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
607 reiserfs_write_lock(inode->i_sb);
608 error = journal_begin(&th, inode->i_sb, jbegin_count);
609 reiserfs_write_unlock(inode->i_sb);
614 error = reiserfs_xattr_set_handle(&th, inode, name,
615 buffer, buffer_size, flags);
617 reiserfs_write_lock(inode->i_sb);
618 error2 = journal_end(&th);
619 reiserfs_write_unlock(inode->i_sb);
627 * inode->i_mutex: down
630 reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
634 struct dentry *dentry;
637 size_t buffer_pos = 0;
645 * We can't have xattrs attached to v1 items since they don't have
648 if (get_inode_sd_version(inode) == STAT_DATA_V1)
651 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
652 if (IS_ERR(dentry)) {
653 err = PTR_ERR(dentry);
657 down_read(&REISERFS_I(inode)->i_xattr_sem);
659 isize = i_size_read(dentry->d_inode);
661 /* Just return the size needed */
662 if (buffer == NULL) {
663 err = isize - sizeof(struct reiserfs_xattr_header);
667 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
672 while (file_pos < isize) {
677 if (isize - file_pos > PAGE_CACHE_SIZE)
678 chunk = PAGE_CACHE_SIZE;
680 chunk = isize - file_pos;
682 page = reiserfs_get_page(dentry->d_inode, file_pos);
689 data = page_address(page);
691 struct reiserfs_xattr_header *rxh =
692 (struct reiserfs_xattr_header *)data;
693 skip = file_pos = sizeof(struct reiserfs_xattr_header);
695 /* Magic doesn't match up.. */
696 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
698 reiserfs_put_page(page);
699 reiserfs_warning(inode->i_sb, "jdm-20001",
700 "Invalid magic for xattr (%s) "
701 "associated with %k", name,
706 hash = le32_to_cpu(rxh->h_hash);
708 memcpy(buffer + buffer_pos, data + skip, chunk);
710 reiserfs_put_page(page);
715 err = isize - sizeof(struct reiserfs_xattr_header);
717 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
719 reiserfs_warning(inode->i_sb, "jdm-20002",
720 "Invalid hash for xattr (%s) associated "
721 "with %k", name, INODE_PKEY(inode));
726 up_read(&REISERFS_I(inode)->i_xattr_sem);
734 * In order to implement different sets of xattr operations for each xattr
735 * prefix with the generic xattr API, a filesystem should create a
736 * null-terminated array of struct xattr_handler (one for each prefix) and
737 * hang a pointer to it off of the s_xattr field of the superblock.
739 * The generic_fooxattr() functions will use this list to dispatch xattr
740 * operations to the correct xattr_handler.
742 #define for_each_xattr_handler(handlers, handler) \
743 for ((handler) = *(handlers)++; \
745 (handler) = *(handlers)++)
747 /* This is the implementation for the xattr plugin infrastructure */
748 static inline const struct xattr_handler *
749 find_xattr_handler_prefix(const struct xattr_handler **handlers,
752 const struct xattr_handler *xah;
757 for_each_xattr_handler(handlers, xah) {
758 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
767 * Inode operation getxattr()
770 reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
773 const struct xattr_handler *handler;
775 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
777 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
780 return handler->get(dentry, name, buffer, size, handler->flags);
784 * Inode operation setxattr()
786 * dentry->d_inode->i_mutex down
789 reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
790 size_t size, int flags)
792 const struct xattr_handler *handler;
794 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
796 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
799 return handler->set(dentry, name, value, size, flags, handler->flags);
803 * Inode operation removexattr()
805 * dentry->d_inode->i_mutex down
807 int reiserfs_removexattr(struct dentry *dentry, const char *name)
809 const struct xattr_handler *handler;
811 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
813 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
816 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
819 struct listxattr_buf {
820 struct dir_context ctx;
824 struct dentry *dentry;
827 static int listxattr_filler(void *buf, const char *name, int namelen,
828 loff_t offset, u64 ino, unsigned int d_type)
830 struct listxattr_buf *b = (struct listxattr_buf *)buf;
833 if (name[0] != '.' ||
834 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
835 const struct xattr_handler *handler;
837 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
839 if (!handler) /* Unsupported xattr name */
842 size = handler->list(b->dentry, b->buf + b->pos,
843 b->size, name, namelen,
848 size = handler->list(b->dentry, NULL, 0, name,
849 namelen, handler->flags);
858 * Inode operation listxattr()
860 * We totally ignore the generic listxattr here because it would be stupid
861 * not to. Since the xattrs are organized in a directory, we can just
862 * readdir to find them.
864 ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
868 struct listxattr_buf buf = {
869 .ctx.actor = listxattr_filler,
872 .size = buffer ? size : 0,
875 if (!dentry->d_inode)
878 if (!dentry->d_sb->s_xattr ||
879 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
882 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
886 err = 0; /* Not an error if there aren't any xattrs */
890 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
891 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
892 mutex_unlock(&dir->d_inode->i_mutex);
902 static int create_privroot(struct dentry *dentry)
905 struct inode *inode = dentry->d_parent->d_inode;
907 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
909 err = xattr_mkdir(inode, dentry, 0700);
910 if (err || !dentry->d_inode) {
911 reiserfs_warning(dentry->d_sb, "jdm-20006",
912 "xattrs/ACLs enabled and couldn't "
913 "find/create .reiserfs_priv. "
918 dentry->d_inode->i_flags |= S_PRIVATE;
919 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
920 "storage.\n", PRIVROOT_NAME);
926 int __init reiserfs_xattr_register_handlers(void) { return 0; }
927 void reiserfs_xattr_unregister_handlers(void) {}
928 static int create_privroot(struct dentry *dentry) { return 0; }
931 /* Actual operations that are exported to VFS-land */
932 static const struct xattr_handler *reiserfs_xattr_handlers[] = {
933 #ifdef CONFIG_REISERFS_FS_XATTR
934 &reiserfs_xattr_user_handler,
935 &reiserfs_xattr_trusted_handler,
937 #ifdef CONFIG_REISERFS_FS_SECURITY
938 &reiserfs_xattr_security_handler,
940 #ifdef CONFIG_REISERFS_FS_POSIX_ACL
941 &posix_acl_access_xattr_handler,
942 &posix_acl_default_xattr_handler,
947 static int xattr_mount_check(struct super_block *s)
950 * We need generation numbers to ensure that the oid mapping is correct
951 * v3.5 filesystems don't have them.
953 if (old_format_only(s)) {
954 if (reiserfs_xattrs_optional(s)) {
956 * Old format filesystem, but optional xattrs have
957 * been enabled. Error out.
959 reiserfs_warning(s, "jdm-2005",
960 "xattrs/ACLs not supported "
961 "on pre-v3.6 format filesystems. "
970 int reiserfs_permission(struct inode *inode, int mask)
973 * We don't do permission checks on the internal objects.
974 * Permissions are determined by the "owning" object.
976 if (IS_PRIVATE(inode))
979 return generic_permission(inode, mask);
982 static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
987 static const struct dentry_operations xattr_lookup_poison_ops = {
988 .d_revalidate = xattr_hide_revalidate,
991 int reiserfs_lookup_privroot(struct super_block *s)
993 struct dentry *dentry;
996 /* If we don't have the privroot located yet - go find it */
997 mutex_lock(&s->s_root->d_inode->i_mutex);
998 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
999 strlen(PRIVROOT_NAME));
1000 if (!IS_ERR(dentry)) {
1001 REISERFS_SB(s)->priv_root = dentry;
1002 d_set_d_op(dentry, &xattr_lookup_poison_ops);
1003 if (dentry->d_inode)
1004 dentry->d_inode->i_flags |= S_PRIVATE;
1006 err = PTR_ERR(dentry);
1007 mutex_unlock(&s->s_root->d_inode->i_mutex);
1013 * We need to take a copy of the mount flags since things like
1014 * MS_RDONLY don't get set until *after* we're called.
1015 * mount_flags != mount_options
1017 int reiserfs_xattr_init(struct super_block *s, int mount_flags)
1020 struct dentry *privroot = REISERFS_SB(s)->priv_root;
1022 err = xattr_mount_check(s);
1026 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
1027 mutex_lock(&s->s_root->d_inode->i_mutex);
1028 err = create_privroot(REISERFS_SB(s)->priv_root);
1029 mutex_unlock(&s->s_root->d_inode->i_mutex);
1032 if (privroot->d_inode) {
1033 s->s_xattr = reiserfs_xattr_handlers;
1034 mutex_lock(&privroot->d_inode->i_mutex);
1035 if (!REISERFS_SB(s)->xattr_root) {
1036 struct dentry *dentry;
1038 dentry = lookup_one_len(XAROOT_NAME, privroot,
1039 strlen(XAROOT_NAME));
1040 if (!IS_ERR(dentry))
1041 REISERFS_SB(s)->xattr_root = dentry;
1043 err = PTR_ERR(dentry);
1045 mutex_unlock(&privroot->d_inode->i_mutex);
1050 clear_bit(REISERFS_XATTRS_USER, &REISERFS_SB(s)->s_mount_opt);
1051 clear_bit(REISERFS_POSIXACL, &REISERFS_SB(s)->s_mount_opt);
1054 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
1055 if (reiserfs_posixacl(s))
1056 s->s_flags |= MS_POSIXACL;
1058 s->s_flags &= ~MS_POSIXACL;