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 <asm/uaccess.h>
49 #include <net/checksum.h>
50 #include <linux/stat.h>
51 #include <linux/quotaops.h>
52 #include <linux/security.h>
54 #define PRIVROOT_NAME ".reiserfs_priv"
55 #define XAROOT_NAME "xattrs"
58 /* 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. */
61 #ifdef CONFIG_REISERFS_FS_XATTR
62 static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
64 BUG_ON(!mutex_is_locked(&dir->i_mutex));
65 return dir->i_op->create(dir, dentry, mode, true);
69 static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
71 BUG_ON(!mutex_is_locked(&dir->i_mutex));
72 return dir->i_op->mkdir(dir, dentry, mode);
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. */
79 static int xattr_unlink(struct inode *dir, struct dentry *dentry)
82 BUG_ON(!mutex_is_locked(&dir->i_mutex));
84 reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
85 I_MUTEX_CHILD, dir->i_sb);
86 error = dir->i_op->unlink(dir, dentry);
87 mutex_unlock(&dentry->d_inode->i_mutex);
94 static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
97 BUG_ON(!mutex_is_locked(&dir->i_mutex));
99 reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
100 I_MUTEX_CHILD, dir->i_sb);
101 error = dir->i_op->rmdir(dir, dentry);
103 dentry->d_inode->i_flags |= S_DEAD;
104 mutex_unlock(&dentry->d_inode->i_mutex);
111 #define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
113 static struct dentry *open_xa_root(struct super_block *sb, int flags)
115 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
116 struct dentry *xaroot;
117 if (!privroot->d_inode)
118 return ERR_PTR(-ENODATA);
120 mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
122 xaroot = dget(REISERFS_SB(sb)->xattr_root);
124 xaroot = ERR_PTR(-ENODATA);
125 else if (!xaroot->d_inode) {
127 if (xattr_may_create(flags))
128 err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
131 xaroot = ERR_PTR(err);
135 mutex_unlock(&privroot->d_inode->i_mutex);
139 static struct dentry *open_xa_dir(const struct inode *inode, int flags)
141 struct dentry *xaroot, *xadir;
144 xaroot = open_xa_root(inode->i_sb, flags);
148 snprintf(namebuf, sizeof(namebuf), "%X.%X",
149 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
150 inode->i_generation);
152 mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
154 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
155 if (!IS_ERR(xadir) && !xadir->d_inode) {
157 if (xattr_may_create(flags))
158 err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
161 xadir = ERR_PTR(err);
165 mutex_unlock(&xaroot->d_inode->i_mutex);
170 /* The following are side effects of other operations that aren't explicitly
171 * modifying extended attributes. This includes operations such as permissions
172 * or ownership changes, object deletions, etc. */
173 struct reiserfs_dentry_buf {
174 struct dir_context ctx;
175 struct dentry *xadir;
177 struct dentry *dentries[8];
181 fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
182 u64 ino, unsigned int d_type)
184 struct reiserfs_dentry_buf *dbuf = buf;
185 struct dentry *dentry;
186 WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
188 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
191 if (name[0] == '.' && (namelen < 2 ||
192 (namelen == 2 && name[1] == '.')))
195 dentry = lookup_one_len(name, dbuf->xadir, namelen);
196 if (IS_ERR(dentry)) {
197 return PTR_ERR(dentry);
198 } else if (!dentry->d_inode) {
199 /* A directory entry exists, but no file? */
200 reiserfs_error(dentry->d_sb, "xattr-20003",
201 "Corrupted directory: xattr %s listed but "
202 "not found for file %s.\n",
203 dentry->d_name.name, dbuf->xadir->d_name.name);
208 dbuf->dentries[dbuf->count++] = dentry;
213 cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
216 for (i = 0; i < buf->count; i++)
217 if (buf->dentries[i])
218 dput(buf->dentries[i]);
221 static int reiserfs_for_each_xattr(struct inode *inode,
222 int (*action)(struct dentry *, void *),
227 struct reiserfs_dentry_buf buf = {
228 .ctx.actor = fill_with_dentries,
231 /* Skip out, an xattr has no xattrs associated with it */
232 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
235 reiserfs_write_unlock(inode->i_sb);
236 dir = open_xa_dir(inode, XATTR_REPLACE);
239 reiserfs_write_lock(inode->i_sb);
241 } else if (!dir->d_inode) {
243 reiserfs_write_lock(inode->i_sb);
247 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
249 reiserfs_write_lock(inode->i_sb);
253 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
258 for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {
259 struct dentry *dentry = buf.dentries[i];
261 if (!S_ISDIR(dentry->d_inode->i_mode))
262 err = action(dentry, data);
265 buf.dentries[i] = NULL;
271 mutex_unlock(&dir->d_inode->i_mutex);
273 cleanup_dentry_buf(&buf);
276 /* We start a transaction here to avoid a ABBA situation
277 * between the xattr root's i_mutex and the journal lock.
278 * This doesn't incur much additional overhead since the
279 * new transaction will just nest inside the
280 * outer transaction. */
281 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
282 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
283 struct reiserfs_transaction_handle th;
284 err = journal_begin(&th, inode->i_sb, blocks);
287 reiserfs_mutex_lock_nested_safe(
288 &dir->d_parent->d_inode->i_mutex,
289 I_MUTEX_XATTR, inode->i_sb);
290 err = action(dir, data);
291 jerror = journal_end(&th, inode->i_sb, blocks);
292 mutex_unlock(&dir->d_parent->d_inode->i_mutex);
299 /* -ENODATA isn't an error */
305 static int delete_one_xattr(struct dentry *dentry, void *data)
307 struct inode *dir = dentry->d_parent->d_inode;
309 /* This is the xattr dir, handle specially. */
310 if (S_ISDIR(dentry->d_inode->i_mode))
311 return xattr_rmdir(dir, dentry);
313 return xattr_unlink(dir, dentry);
316 static int chown_one_xattr(struct dentry *dentry, void *data)
318 struct iattr *attrs = data;
319 int ia_valid = attrs->ia_valid;
323 * We only want the ownership bits. Otherwise, we'll do
324 * things like change a directory to a regular file if
327 attrs->ia_valid &= (ATTR_UID|ATTR_GID);
328 err = reiserfs_setattr(dentry, attrs);
329 attrs->ia_valid = ia_valid;
334 /* No i_mutex, but the inode is unconnected. */
335 int reiserfs_delete_xattrs(struct inode *inode)
337 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
339 reiserfs_warning(inode->i_sb, "jdm-20004",
340 "Couldn't delete all xattrs (%d)\n", err);
344 /* inode->i_mutex: down */
345 int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
347 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
349 reiserfs_warning(inode->i_sb, "jdm-20007",
350 "Couldn't chown all xattrs (%d)\n", err);
354 #ifdef CONFIG_REISERFS_FS_XATTR
355 /* Returns a dentry corresponding to a specific extended attribute file
356 * for the inode. If flags allow, the file is created. Otherwise, a
357 * valid or negative dentry, or an error is returned. */
358 static struct dentry *xattr_lookup(struct inode *inode, const char *name,
361 struct dentry *xadir, *xafile;
364 xadir = open_xa_dir(inode, flags);
366 return ERR_CAST(xadir);
368 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
369 xafile = lookup_one_len(name, xadir, strlen(name));
370 if (IS_ERR(xafile)) {
371 err = PTR_ERR(xafile);
375 if (xafile->d_inode && (flags & XATTR_CREATE))
378 if (!xafile->d_inode) {
380 if (xattr_may_create(flags))
381 err = xattr_create(xadir->d_inode, xafile,
388 mutex_unlock(&xadir->d_inode->i_mutex);
395 /* Internal operations on file data */
396 static inline void reiserfs_put_page(struct page *page)
399 page_cache_release(page);
402 static struct page *reiserfs_get_page(struct inode *dir, size_t n)
404 struct address_space *mapping = dir->i_mapping;
406 /* We can deadlock if we try to free dentries,
407 and an unlink/rmdir has just occurred - GFP_NOFS avoids this */
408 mapping_set_gfp_mask(mapping, GFP_NOFS);
409 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
418 reiserfs_put_page(page);
419 return ERR_PTR(-EIO);
422 static inline __u32 xattr_hash(const char *msg, int len)
424 return csum_partial(msg, len, 0);
427 int reiserfs_commit_write(struct file *f, struct page *page,
428 unsigned from, unsigned to);
430 static void update_ctime(struct inode *inode)
432 struct timespec now = current_fs_time(inode->i_sb);
433 if (inode_unhashed(inode) || !inode->i_nlink ||
434 timespec_equal(&inode->i_ctime, &now))
437 inode->i_ctime = CURRENT_TIME_SEC;
438 mark_inode_dirty(inode);
441 static int lookup_and_delete_xattr(struct inode *inode, const char *name)
444 struct dentry *dentry, *xadir;
446 xadir = open_xa_dir(inode, XATTR_REPLACE);
448 return PTR_ERR(xadir);
450 mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
451 dentry = lookup_one_len(name, xadir, strlen(name));
452 if (IS_ERR(dentry)) {
453 err = PTR_ERR(dentry);
457 if (dentry->d_inode) {
458 reiserfs_write_lock(inode->i_sb);
459 err = xattr_unlink(xadir->d_inode, dentry);
460 reiserfs_write_unlock(inode->i_sb);
466 mutex_unlock(&xadir->d_inode->i_mutex);
472 /* Generic extended attribute operations that can be used by xa plugins */
475 * inode->i_mutex: down
478 reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
479 struct inode *inode, const char *name,
480 const void *buffer, size_t buffer_size, int flags)
483 struct dentry *dentry;
487 size_t buffer_pos = 0;
491 if (get_inode_sd_version(inode) == STAT_DATA_V1)
494 reiserfs_write_unlock(inode->i_sb);
497 err = lookup_and_delete_xattr(inode, name);
498 reiserfs_write_lock(inode->i_sb);
502 dentry = xattr_lookup(inode, name, flags);
503 if (IS_ERR(dentry)) {
504 reiserfs_write_lock(inode->i_sb);
505 return PTR_ERR(dentry);
508 down_write(&REISERFS_I(inode)->i_xattr_sem);
510 reiserfs_write_lock(inode->i_sb);
512 xahash = xattr_hash(buffer, buffer_size);
513 while (buffer_pos < buffer_size || buffer_pos == 0) {
516 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
517 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
518 chunk = PAGE_CACHE_SIZE;
520 chunk = buffer_size - buffer_pos;
522 page = reiserfs_get_page(dentry->d_inode, file_pos);
529 data = page_address(page);
532 struct reiserfs_xattr_header *rxh;
533 skip = file_pos = sizeof(struct reiserfs_xattr_header);
534 if (chunk + skip > PAGE_CACHE_SIZE)
535 chunk = PAGE_CACHE_SIZE - skip;
536 rxh = (struct reiserfs_xattr_header *)data;
537 rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
538 rxh->h_hash = cpu_to_le32(xahash);
541 err = __reiserfs_write_begin(page, page_offset, chunk + skip);
544 memcpy(data + skip, buffer + buffer_pos, chunk);
545 err = reiserfs_commit_write(NULL, page, page_offset,
546 page_offset + chunk +
550 reiserfs_put_page(page);
554 if (err || buffer_size == 0 || !buffer)
558 new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
559 if (!err && new_size < i_size_read(dentry->d_inode)) {
560 struct iattr newattrs = {
561 .ia_ctime = current_fs_time(inode->i_sb),
563 .ia_valid = ATTR_SIZE | ATTR_CTIME,
566 reiserfs_write_unlock(inode->i_sb);
567 mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
568 inode_dio_wait(dentry->d_inode);
569 reiserfs_write_lock(inode->i_sb);
571 err = reiserfs_setattr(dentry, &newattrs);
572 mutex_unlock(&dentry->d_inode->i_mutex);
576 up_write(&REISERFS_I(inode)->i_xattr_sem);
581 /* We need to start a transaction to maintain lock ordering */
582 int reiserfs_xattr_set(struct inode *inode, const char *name,
583 const void *buffer, size_t buffer_size, int flags)
586 struct reiserfs_transaction_handle th;
588 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
590 if (!(flags & XATTR_REPLACE))
591 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
593 reiserfs_write_lock(inode->i_sb);
594 error = journal_begin(&th, inode->i_sb, jbegin_count);
596 reiserfs_write_unlock(inode->i_sb);
600 error = reiserfs_xattr_set_handle(&th, inode, name,
601 buffer, buffer_size, flags);
603 error2 = journal_end(&th, inode->i_sb, jbegin_count);
606 reiserfs_write_unlock(inode->i_sb);
612 * inode->i_mutex: down
615 reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
619 struct dentry *dentry;
622 size_t buffer_pos = 0;
629 /* We can't have xattrs attached to v1 items since they don't have
630 * generation numbers */
631 if (get_inode_sd_version(inode) == STAT_DATA_V1)
634 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
635 if (IS_ERR(dentry)) {
636 err = PTR_ERR(dentry);
640 down_read(&REISERFS_I(inode)->i_xattr_sem);
642 isize = i_size_read(dentry->d_inode);
644 /* Just return the size needed */
645 if (buffer == NULL) {
646 err = isize - sizeof(struct reiserfs_xattr_header);
650 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
655 while (file_pos < isize) {
659 if (isize - file_pos > PAGE_CACHE_SIZE)
660 chunk = PAGE_CACHE_SIZE;
662 chunk = isize - file_pos;
664 page = reiserfs_get_page(dentry->d_inode, file_pos);
671 data = page_address(page);
673 struct reiserfs_xattr_header *rxh =
674 (struct reiserfs_xattr_header *)data;
675 skip = file_pos = sizeof(struct reiserfs_xattr_header);
677 /* Magic doesn't match up.. */
678 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
680 reiserfs_put_page(page);
681 reiserfs_warning(inode->i_sb, "jdm-20001",
682 "Invalid magic for xattr (%s) "
683 "associated with %k", name,
688 hash = le32_to_cpu(rxh->h_hash);
690 memcpy(buffer + buffer_pos, data + skip, chunk);
692 reiserfs_put_page(page);
697 err = isize - sizeof(struct reiserfs_xattr_header);
699 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
701 reiserfs_warning(inode->i_sb, "jdm-20002",
702 "Invalid hash for xattr (%s) associated "
703 "with %k", name, INODE_PKEY(inode));
708 up_read(&REISERFS_I(inode)->i_xattr_sem);
716 * In order to implement different sets of xattr operations for each xattr
717 * prefix with the generic xattr API, a filesystem should create a
718 * null-terminated array of struct xattr_handler (one for each prefix) and
719 * hang a pointer to it off of the s_xattr field of the superblock.
721 * The generic_fooxattr() functions will use this list to dispatch xattr
722 * operations to the correct xattr_handler.
724 #define for_each_xattr_handler(handlers, handler) \
725 for ((handler) = *(handlers)++; \
727 (handler) = *(handlers)++)
729 /* This is the implementation for the xattr plugin infrastructure */
730 static inline const struct xattr_handler *
731 find_xattr_handler_prefix(const struct xattr_handler **handlers,
734 const struct xattr_handler *xah;
739 for_each_xattr_handler(handlers, xah) {
740 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
749 * Inode operation getxattr()
752 reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
755 const struct xattr_handler *handler;
757 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
759 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
762 return handler->get(dentry, name, buffer, size, handler->flags);
766 * Inode operation setxattr()
768 * dentry->d_inode->i_mutex down
771 reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
772 size_t size, int flags)
774 const struct xattr_handler *handler;
776 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
778 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
781 return handler->set(dentry, name, value, size, flags, handler->flags);
785 * Inode operation removexattr()
787 * dentry->d_inode->i_mutex down
789 int reiserfs_removexattr(struct dentry *dentry, const char *name)
791 const struct xattr_handler *handler;
792 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
794 if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
797 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
800 struct listxattr_buf {
801 struct dir_context ctx;
805 struct dentry *dentry;
808 static int listxattr_filler(void *buf, const char *name, int namelen,
809 loff_t offset, u64 ino, unsigned int d_type)
811 struct listxattr_buf *b = (struct listxattr_buf *)buf;
813 if (name[0] != '.' ||
814 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
815 const struct xattr_handler *handler;
816 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
818 if (!handler) /* Unsupported xattr name */
821 size = handler->list(b->dentry, b->buf + b->pos,
822 b->size, name, namelen,
827 size = handler->list(b->dentry, NULL, 0, name,
828 namelen, handler->flags);
837 * Inode operation listxattr()
839 * We totally ignore the generic listxattr here because it would be stupid
840 * not to. Since the xattrs are organized in a directory, we can just
841 * readdir to find them.
843 ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
847 struct listxattr_buf buf = {
848 .ctx.actor = listxattr_filler,
851 .size = buffer ? size : 0,
854 if (!dentry->d_inode)
857 if (!dentry->d_sb->s_xattr ||
858 get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
861 dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
865 err = 0; /* Not an error if there aren't any xattrs */
869 mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
870 err = reiserfs_readdir_inode(dir->d_inode, &buf.ctx);
871 mutex_unlock(&dir->d_inode->i_mutex);
881 static int create_privroot(struct dentry *dentry)
884 struct inode *inode = dentry->d_parent->d_inode;
885 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
887 err = xattr_mkdir(inode, dentry, 0700);
888 if (err || !dentry->d_inode) {
889 reiserfs_warning(dentry->d_sb, "jdm-20006",
890 "xattrs/ACLs enabled and couldn't "
891 "find/create .reiserfs_priv. "
896 dentry->d_inode->i_flags |= S_PRIVATE;
897 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
898 "storage.\n", PRIVROOT_NAME);
904 int __init reiserfs_xattr_register_handlers(void) { return 0; }
905 void reiserfs_xattr_unregister_handlers(void) {}
906 static int create_privroot(struct dentry *dentry) { return 0; }
909 /* Actual operations that are exported to VFS-land */
910 static const struct xattr_handler *reiserfs_xattr_handlers[] = {
911 #ifdef CONFIG_REISERFS_FS_XATTR
912 &reiserfs_xattr_user_handler,
913 &reiserfs_xattr_trusted_handler,
915 #ifdef CONFIG_REISERFS_FS_SECURITY
916 &reiserfs_xattr_security_handler,
918 #ifdef CONFIG_REISERFS_FS_POSIX_ACL
919 &reiserfs_posix_acl_access_handler,
920 &reiserfs_posix_acl_default_handler,
925 static int xattr_mount_check(struct super_block *s)
927 /* We need generation numbers to ensure that the oid mapping is correct
928 * v3.5 filesystems don't have them. */
929 if (old_format_only(s)) {
930 if (reiserfs_xattrs_optional(s)) {
931 /* Old format filesystem, but optional xattrs have
932 * been enabled. Error out. */
933 reiserfs_warning(s, "jdm-2005",
934 "xattrs/ACLs not supported "
935 "on pre-v3.6 format filesystems. "
944 int reiserfs_permission(struct inode *inode, int mask)
947 * We don't do permission checks on the internal objects.
948 * Permissions are determined by the "owning" object.
950 if (IS_PRIVATE(inode))
953 return generic_permission(inode, mask);
956 static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
961 static const struct dentry_operations xattr_lookup_poison_ops = {
962 .d_revalidate = xattr_hide_revalidate,
965 int reiserfs_lookup_privroot(struct super_block *s)
967 struct dentry *dentry;
970 /* If we don't have the privroot located yet - go find it */
971 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
972 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
973 strlen(PRIVROOT_NAME));
974 if (!IS_ERR(dentry)) {
975 REISERFS_SB(s)->priv_root = dentry;
976 d_set_d_op(dentry, &xattr_lookup_poison_ops);
978 dentry->d_inode->i_flags |= S_PRIVATE;
980 err = PTR_ERR(dentry);
981 mutex_unlock(&s->s_root->d_inode->i_mutex);
986 /* We need to take a copy of the mount flags since things like
987 * MS_RDONLY don't get set until *after* we're called.
988 * mount_flags != mount_options */
989 int reiserfs_xattr_init(struct super_block *s, int mount_flags)
992 struct dentry *privroot = REISERFS_SB(s)->priv_root;
994 err = xattr_mount_check(s);
998 if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
999 reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
1000 err = create_privroot(REISERFS_SB(s)->priv_root);
1001 mutex_unlock(&s->s_root->d_inode->i_mutex);
1004 if (privroot->d_inode) {
1005 s->s_xattr = reiserfs_xattr_handlers;
1006 reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
1007 if (!REISERFS_SB(s)->xattr_root) {
1008 struct dentry *dentry;
1009 dentry = lookup_one_len(XAROOT_NAME, privroot,
1010 strlen(XAROOT_NAME));
1011 if (!IS_ERR(dentry))
1012 REISERFS_SB(s)->xattr_root = dentry;
1014 err = PTR_ERR(dentry);
1016 mutex_unlock(&privroot->d_inode->i_mutex);
1021 clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1022 clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1025 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
1026 if (reiserfs_posixacl(s))
1027 s->s_flags |= MS_POSIXACL;
1029 s->s_flags &= ~MS_POSIXACL;