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(&d_inode(dentry
)->i_mutex
, I_MUTEX_CHILD
);
91 error
= dir
->i_op
->unlink(dir
, dentry
);
92 mutex_unlock(&d_inode(dentry
)->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(&d_inode(dentry
)->i_mutex
, I_MUTEX_CHILD
);
106 error
= dir
->i_op
->rmdir(dir
, dentry
);
108 d_inode(dentry
)->i_flags
|= S_DEAD
;
109 mutex_unlock(&d_inode(dentry
)->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 (d_really_is_negative(privroot
))
124 return ERR_PTR(-ENODATA
);
126 mutex_lock_nested(&d_inode(privroot
)->i_mutex
, I_MUTEX_XATTR
);
128 xaroot
= dget(REISERFS_SB(sb
)->xattr_root
);
130 xaroot
= ERR_PTR(-ENODATA
);
131 else if (d_really_is_negative(xaroot
)) {
134 if (xattr_may_create(flags
))
135 err
= xattr_mkdir(d_inode(privroot
), xaroot
, 0700);
138 xaroot
= ERR_PTR(err
);
142 mutex_unlock(&d_inode(privroot
)->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(&d_inode(xaroot
)->i_mutex
, I_MUTEX_XATTR
);
161 xadir
= lookup_one_len(namebuf
, xaroot
, strlen(namebuf
));
162 if (!IS_ERR(xadir
) && d_really_is_negative(xadir
)) {
165 if (xattr_may_create(flags
))
166 err
= xattr_mkdir(d_inode(xaroot
), xadir
, 0700);
169 xadir
= ERR_PTR(err
);
173 mutex_unlock(&d_inode(xaroot
)->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(struct dir_context
*ctx
, const char *name
, int namelen
,
192 loff_t offset
, u64 ino
, unsigned int d_type
)
194 struct reiserfs_dentry_buf
*dbuf
=
195 container_of(ctx
, struct reiserfs_dentry_buf
, ctx
);
196 struct dentry
*dentry
;
198 WARN_ON_ONCE(!mutex_is_locked(&d_inode(dbuf
->xadir
)->i_mutex
));
200 if (dbuf
->count
== ARRAY_SIZE(dbuf
->dentries
))
203 if (name
[0] == '.' && (namelen
< 2 ||
204 (namelen
== 2 && name
[1] == '.')))
207 dentry
= lookup_one_len(name
, dbuf
->xadir
, namelen
);
208 if (IS_ERR(dentry
)) {
209 return PTR_ERR(dentry
);
210 } else if (d_really_is_negative(dentry
)) {
211 /* A directory entry exists, but no file? */
212 reiserfs_error(dentry
->d_sb
, "xattr-20003",
213 "Corrupted directory: xattr %pd listed but "
214 "not found for file %pd.\n",
215 dentry
, dbuf
->xadir
);
220 dbuf
->dentries
[dbuf
->count
++] = dentry
;
225 cleanup_dentry_buf(struct reiserfs_dentry_buf
*buf
)
229 for (i
= 0; i
< buf
->count
; i
++)
230 if (buf
->dentries
[i
])
231 dput(buf
->dentries
[i
]);
234 static int reiserfs_for_each_xattr(struct inode
*inode
,
235 int (*action
)(struct dentry
*, void *),
240 struct reiserfs_dentry_buf buf
= {
241 .ctx
.actor
= fill_with_dentries
,
244 /* Skip out, an xattr has no xattrs associated with it */
245 if (IS_PRIVATE(inode
) || get_inode_sd_version(inode
) == STAT_DATA_V1
)
248 dir
= open_xa_dir(inode
, XATTR_REPLACE
);
252 } else if (d_really_is_negative(dir
)) {
257 mutex_lock_nested(&d_inode(dir
)->i_mutex
, I_MUTEX_XATTR
);
261 err
= reiserfs_readdir_inode(d_inode(dir
), &buf
.ctx
);
266 for (i
= 0; !err
&& i
< buf
.count
&& buf
.dentries
[i
]; i
++) {
267 struct dentry
*dentry
= buf
.dentries
[i
];
269 if (!d_is_dir(dentry
))
270 err
= action(dentry
, data
);
273 buf
.dentries
[i
] = NULL
;
279 mutex_unlock(&d_inode(dir
)->i_mutex
);
281 cleanup_dentry_buf(&buf
);
285 * We start a transaction here to avoid a ABBA situation
286 * between the xattr root's i_mutex and the journal lock.
287 * This doesn't incur much additional overhead since the
288 * new transaction will just nest inside the
291 int blocks
= JOURNAL_PER_BALANCE_CNT
* 2 + 2 +
292 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode
->i_sb
);
293 struct reiserfs_transaction_handle th
;
295 reiserfs_write_lock(inode
->i_sb
);
296 err
= journal_begin(&th
, inode
->i_sb
, blocks
);
297 reiserfs_write_unlock(inode
->i_sb
);
301 mutex_lock_nested(&d_inode(dir
->d_parent
)->i_mutex
,
303 err
= action(dir
, data
);
304 reiserfs_write_lock(inode
->i_sb
);
305 jerror
= journal_end(&th
);
306 reiserfs_write_unlock(inode
->i_sb
);
307 mutex_unlock(&d_inode(dir
->d_parent
)->i_mutex
);
314 /* -ENODATA isn't an error */
320 static int delete_one_xattr(struct dentry
*dentry
, void *data
)
322 struct inode
*dir
= d_inode(dentry
->d_parent
);
324 /* This is the xattr dir, handle specially. */
325 if (d_is_dir(dentry
))
326 return xattr_rmdir(dir
, dentry
);
328 return xattr_unlink(dir
, dentry
);
331 static int chown_one_xattr(struct dentry
*dentry
, void *data
)
333 struct iattr
*attrs
= data
;
334 int ia_valid
= attrs
->ia_valid
;
338 * We only want the ownership bits. Otherwise, we'll do
339 * things like change a directory to a regular file if
342 attrs
->ia_valid
&= (ATTR_UID
|ATTR_GID
);
343 err
= reiserfs_setattr(dentry
, attrs
);
344 attrs
->ia_valid
= ia_valid
;
349 /* No i_mutex, but the inode is unconnected. */
350 int reiserfs_delete_xattrs(struct inode
*inode
)
352 int err
= reiserfs_for_each_xattr(inode
, delete_one_xattr
, NULL
);
355 reiserfs_warning(inode
->i_sb
, "jdm-20004",
356 "Couldn't delete all xattrs (%d)\n", err
);
360 /* inode->i_mutex: down */
361 int reiserfs_chown_xattrs(struct inode
*inode
, struct iattr
*attrs
)
363 int err
= reiserfs_for_each_xattr(inode
, chown_one_xattr
, attrs
);
366 reiserfs_warning(inode
->i_sb
, "jdm-20007",
367 "Couldn't chown all xattrs (%d)\n", err
);
371 #ifdef CONFIG_REISERFS_FS_XATTR
373 * Returns a dentry corresponding to a specific extended attribute file
374 * for the inode. If flags allow, the file is created. Otherwise, a
375 * valid or negative dentry, or an error is returned.
377 static struct dentry
*xattr_lookup(struct inode
*inode
, const char *name
,
380 struct dentry
*xadir
, *xafile
;
383 xadir
= open_xa_dir(inode
, flags
);
385 return ERR_CAST(xadir
);
387 mutex_lock_nested(&d_inode(xadir
)->i_mutex
, I_MUTEX_XATTR
);
388 xafile
= lookup_one_len(name
, xadir
, strlen(name
));
389 if (IS_ERR(xafile
)) {
390 err
= PTR_ERR(xafile
);
394 if (d_really_is_positive(xafile
) && (flags
& XATTR_CREATE
))
397 if (d_really_is_negative(xafile
)) {
399 if (xattr_may_create(flags
))
400 err
= xattr_create(d_inode(xadir
), xafile
,
407 mutex_unlock(&d_inode(xadir
)->i_mutex
);
414 /* Internal operations on file data */
415 static inline void reiserfs_put_page(struct page
*page
)
418 page_cache_release(page
);
421 static struct page
*reiserfs_get_page(struct inode
*dir
, size_t n
)
423 struct address_space
*mapping
= dir
->i_mapping
;
426 * We can deadlock if we try to free dentries,
427 * and an unlink/rmdir has just occurred - GFP_NOFS avoids this
429 mapping_set_gfp_mask(mapping
, GFP_NOFS
);
430 page
= read_mapping_page(mapping
, n
>> PAGE_CACHE_SHIFT
, NULL
);
439 reiserfs_put_page(page
);
440 return ERR_PTR(-EIO
);
443 static inline __u32
xattr_hash(const char *msg
, int len
)
445 return csum_partial(msg
, len
, 0);
448 int reiserfs_commit_write(struct file
*f
, struct page
*page
,
449 unsigned from
, unsigned to
);
451 static void update_ctime(struct inode
*inode
)
453 struct timespec now
= current_fs_time(inode
->i_sb
);
455 if (inode_unhashed(inode
) || !inode
->i_nlink
||
456 timespec_equal(&inode
->i_ctime
, &now
))
459 inode
->i_ctime
= CURRENT_TIME_SEC
;
460 mark_inode_dirty(inode
);
463 static int lookup_and_delete_xattr(struct inode
*inode
, const char *name
)
466 struct dentry
*dentry
, *xadir
;
468 xadir
= open_xa_dir(inode
, XATTR_REPLACE
);
470 return PTR_ERR(xadir
);
472 mutex_lock_nested(&d_inode(xadir
)->i_mutex
, I_MUTEX_XATTR
);
473 dentry
= lookup_one_len(name
, xadir
, strlen(name
));
474 if (IS_ERR(dentry
)) {
475 err
= PTR_ERR(dentry
);
479 if (d_really_is_positive(dentry
)) {
480 err
= xattr_unlink(d_inode(xadir
), dentry
);
486 mutex_unlock(&d_inode(xadir
)->i_mutex
);
492 /* Generic extended attribute operations that can be used by xa plugins */
495 * inode->i_mutex: down
498 reiserfs_xattr_set_handle(struct reiserfs_transaction_handle
*th
,
499 struct inode
*inode
, const char *name
,
500 const void *buffer
, size_t buffer_size
, int flags
)
503 struct dentry
*dentry
;
507 size_t buffer_pos
= 0;
511 if (get_inode_sd_version(inode
) == STAT_DATA_V1
)
515 err
= lookup_and_delete_xattr(inode
, name
);
519 dentry
= xattr_lookup(inode
, name
, flags
);
521 return PTR_ERR(dentry
);
523 down_write(&REISERFS_I(inode
)->i_xattr_sem
);
525 xahash
= xattr_hash(buffer
, buffer_size
);
526 while (buffer_pos
< buffer_size
|| buffer_pos
== 0) {
529 size_t page_offset
= (file_pos
& (PAGE_CACHE_SIZE
- 1));
531 if (buffer_size
- buffer_pos
> PAGE_CACHE_SIZE
)
532 chunk
= PAGE_CACHE_SIZE
;
534 chunk
= buffer_size
- buffer_pos
;
536 page
= reiserfs_get_page(d_inode(dentry
), file_pos
);
543 data
= page_address(page
);
546 struct reiserfs_xattr_header
*rxh
;
548 skip
= file_pos
= sizeof(struct reiserfs_xattr_header
);
549 if (chunk
+ skip
> PAGE_CACHE_SIZE
)
550 chunk
= PAGE_CACHE_SIZE
- skip
;
551 rxh
= (struct reiserfs_xattr_header
*)data
;
552 rxh
->h_magic
= cpu_to_le32(REISERFS_XATTR_MAGIC
);
553 rxh
->h_hash
= cpu_to_le32(xahash
);
556 reiserfs_write_lock(inode
->i_sb
);
557 err
= __reiserfs_write_begin(page
, page_offset
, chunk
+ skip
);
560 memcpy(data
+ skip
, buffer
+ buffer_pos
, chunk
);
561 err
= reiserfs_commit_write(NULL
, page
, page_offset
,
562 page_offset
+ chunk
+
565 reiserfs_write_unlock(inode
->i_sb
);
567 reiserfs_put_page(page
);
571 if (err
|| buffer_size
== 0 || !buffer
)
575 new_size
= buffer_size
+ sizeof(struct reiserfs_xattr_header
);
576 if (!err
&& new_size
< i_size_read(d_inode(dentry
))) {
577 struct iattr newattrs
= {
578 .ia_ctime
= current_fs_time(inode
->i_sb
),
580 .ia_valid
= ATTR_SIZE
| ATTR_CTIME
,
583 mutex_lock_nested(&d_inode(dentry
)->i_mutex
, I_MUTEX_XATTR
);
584 inode_dio_wait(d_inode(dentry
));
586 err
= reiserfs_setattr(dentry
, &newattrs
);
587 mutex_unlock(&d_inode(dentry
)->i_mutex
);
591 up_write(&REISERFS_I(inode
)->i_xattr_sem
);
596 /* We need to start a transaction to maintain lock ordering */
597 int reiserfs_xattr_set(struct inode
*inode
, const char *name
,
598 const void *buffer
, size_t buffer_size
, int flags
)
601 struct reiserfs_transaction_handle th
;
603 size_t jbegin_count
= reiserfs_xattr_nblocks(inode
, buffer_size
);
605 if (!(flags
& XATTR_REPLACE
))
606 jbegin_count
+= reiserfs_xattr_jcreate_nblocks(inode
);
608 reiserfs_write_lock(inode
->i_sb
);
609 error
= journal_begin(&th
, inode
->i_sb
, jbegin_count
);
610 reiserfs_write_unlock(inode
->i_sb
);
615 error
= reiserfs_xattr_set_handle(&th
, inode
, name
,
616 buffer
, buffer_size
, flags
);
618 reiserfs_write_lock(inode
->i_sb
);
619 error2
= journal_end(&th
);
620 reiserfs_write_unlock(inode
->i_sb
);
628 * inode->i_mutex: down
631 reiserfs_xattr_get(struct inode
*inode
, const char *name
, void *buffer
,
635 struct dentry
*dentry
;
638 size_t buffer_pos
= 0;
646 * We can't have xattrs attached to v1 items since they don't have
649 if (get_inode_sd_version(inode
) == STAT_DATA_V1
)
652 dentry
= xattr_lookup(inode
, name
, XATTR_REPLACE
);
653 if (IS_ERR(dentry
)) {
654 err
= PTR_ERR(dentry
);
658 down_read(&REISERFS_I(inode
)->i_xattr_sem
);
660 isize
= i_size_read(d_inode(dentry
));
662 /* Just return the size needed */
663 if (buffer
== NULL
) {
664 err
= isize
- sizeof(struct reiserfs_xattr_header
);
668 if (buffer_size
< isize
- sizeof(struct reiserfs_xattr_header
)) {
673 while (file_pos
< isize
) {
678 if (isize
- file_pos
> PAGE_CACHE_SIZE
)
679 chunk
= PAGE_CACHE_SIZE
;
681 chunk
= isize
- file_pos
;
683 page
= reiserfs_get_page(d_inode(dentry
), file_pos
);
690 data
= page_address(page
);
692 struct reiserfs_xattr_header
*rxh
=
693 (struct reiserfs_xattr_header
*)data
;
694 skip
= file_pos
= sizeof(struct reiserfs_xattr_header
);
696 /* Magic doesn't match up.. */
697 if (rxh
->h_magic
!= cpu_to_le32(REISERFS_XATTR_MAGIC
)) {
699 reiserfs_put_page(page
);
700 reiserfs_warning(inode
->i_sb
, "jdm-20001",
701 "Invalid magic for xattr (%s) "
702 "associated with %k", name
,
707 hash
= le32_to_cpu(rxh
->h_hash
);
709 memcpy(buffer
+ buffer_pos
, data
+ skip
, chunk
);
711 reiserfs_put_page(page
);
716 err
= isize
- sizeof(struct reiserfs_xattr_header
);
718 if (xattr_hash(buffer
, isize
- sizeof(struct reiserfs_xattr_header
)) !=
720 reiserfs_warning(inode
->i_sb
, "jdm-20002",
721 "Invalid hash for xattr (%s) associated "
722 "with %k", name
, INODE_PKEY(inode
));
727 up_read(&REISERFS_I(inode
)->i_xattr_sem
);
735 * In order to implement different sets of xattr operations for each xattr
736 * prefix with the generic xattr API, a filesystem should create a
737 * null-terminated array of struct xattr_handler (one for each prefix) and
738 * hang a pointer to it off of the s_xattr field of the superblock.
740 * The generic_fooxattr() functions will use this list to dispatch xattr
741 * operations to the correct xattr_handler.
743 #define for_each_xattr_handler(handlers, handler) \
744 for ((handler) = *(handlers)++; \
746 (handler) = *(handlers)++)
748 /* This is the implementation for the xattr plugin infrastructure */
749 static inline const struct xattr_handler
*
750 find_xattr_handler_prefix(const struct xattr_handler
**handlers
,
753 const struct xattr_handler
*xah
;
758 for_each_xattr_handler(handlers
, xah
) {
759 if (strncmp(xah
->prefix
, name
, strlen(xah
->prefix
)) == 0)
766 struct listxattr_buf
{
767 struct dir_context ctx
;
771 struct dentry
*dentry
;
774 static int listxattr_filler(struct dir_context
*ctx
, const char *name
,
775 int namelen
, loff_t offset
, u64 ino
,
778 struct listxattr_buf
*b
=
779 container_of(ctx
, struct listxattr_buf
, ctx
);
782 if (name
[0] != '.' ||
783 (namelen
!= 1 && (name
[1] != '.' || namelen
!= 2))) {
784 const struct xattr_handler
*handler
;
786 handler
= find_xattr_handler_prefix(b
->dentry
->d_sb
->s_xattr
,
788 if (!handler
) /* Unsupported xattr name */
791 size
= handler
->list(handler
, b
->dentry
,
792 b
->buf
+ b
->pos
, b
->size
, name
,
794 if (b
->pos
+ size
> b
->size
) {
799 size
= handler
->list(handler
, b
->dentry
,
800 NULL
, 0, name
, namelen
);
809 * Inode operation listxattr()
811 * We totally ignore the generic listxattr here because it would be stupid
812 * not to. Since the xattrs are organized in a directory, we can just
813 * readdir to find them.
815 ssize_t
reiserfs_listxattr(struct dentry
* dentry
, char *buffer
, size_t size
)
819 struct listxattr_buf buf
= {
820 .ctx
.actor
= listxattr_filler
,
823 .size
= buffer
? size
: 0,
826 if (d_really_is_negative(dentry
))
829 if (!dentry
->d_sb
->s_xattr
||
830 get_inode_sd_version(d_inode(dentry
)) == STAT_DATA_V1
)
833 dir
= open_xa_dir(d_inode(dentry
), XATTR_REPLACE
);
837 err
= 0; /* Not an error if there aren't any xattrs */
841 mutex_lock_nested(&d_inode(dir
)->i_mutex
, I_MUTEX_XATTR
);
842 err
= reiserfs_readdir_inode(d_inode(dir
), &buf
.ctx
);
843 mutex_unlock(&d_inode(dir
)->i_mutex
);
853 static int create_privroot(struct dentry
*dentry
)
856 struct inode
*inode
= d_inode(dentry
->d_parent
);
858 WARN_ON_ONCE(!mutex_is_locked(&inode
->i_mutex
));
860 err
= xattr_mkdir(inode
, dentry
, 0700);
861 if (err
|| d_really_is_negative(dentry
)) {
862 reiserfs_warning(dentry
->d_sb
, "jdm-20006",
863 "xattrs/ACLs enabled and couldn't "
864 "find/create .reiserfs_priv. "
869 d_inode(dentry
)->i_flags
|= S_PRIVATE
;
870 reiserfs_info(dentry
->d_sb
, "Created %s - reserved for xattr "
871 "storage.\n", PRIVROOT_NAME
);
877 int __init
reiserfs_xattr_register_handlers(void) { return 0; }
878 void reiserfs_xattr_unregister_handlers(void) {}
879 static int create_privroot(struct dentry
*dentry
) { return 0; }
882 /* Actual operations that are exported to VFS-land */
883 static const struct xattr_handler
*reiserfs_xattr_handlers
[] = {
884 #ifdef CONFIG_REISERFS_FS_XATTR
885 &reiserfs_xattr_user_handler
,
886 &reiserfs_xattr_trusted_handler
,
888 #ifdef CONFIG_REISERFS_FS_SECURITY
889 &reiserfs_xattr_security_handler
,
891 #ifdef CONFIG_REISERFS_FS_POSIX_ACL
892 &posix_acl_access_xattr_handler
,
893 &posix_acl_default_xattr_handler
,
898 static int xattr_mount_check(struct super_block
*s
)
901 * We need generation numbers to ensure that the oid mapping is correct
902 * v3.5 filesystems don't have them.
904 if (old_format_only(s
)) {
905 if (reiserfs_xattrs_optional(s
)) {
907 * Old format filesystem, but optional xattrs have
908 * been enabled. Error out.
910 reiserfs_warning(s
, "jdm-2005",
911 "xattrs/ACLs not supported "
912 "on pre-v3.6 format filesystems. "
921 int reiserfs_permission(struct inode
*inode
, int mask
)
924 * We don't do permission checks on the internal objects.
925 * Permissions are determined by the "owning" object.
927 if (IS_PRIVATE(inode
))
930 return generic_permission(inode
, mask
);
933 static int xattr_hide_revalidate(struct dentry
*dentry
, unsigned int flags
)
938 static const struct dentry_operations xattr_lookup_poison_ops
= {
939 .d_revalidate
= xattr_hide_revalidate
,
942 int reiserfs_lookup_privroot(struct super_block
*s
)
944 struct dentry
*dentry
;
947 /* If we don't have the privroot located yet - go find it */
948 mutex_lock(&d_inode(s
->s_root
)->i_mutex
);
949 dentry
= lookup_one_len(PRIVROOT_NAME
, s
->s_root
,
950 strlen(PRIVROOT_NAME
));
951 if (!IS_ERR(dentry
)) {
952 REISERFS_SB(s
)->priv_root
= dentry
;
953 d_set_d_op(dentry
, &xattr_lookup_poison_ops
);
954 if (d_really_is_positive(dentry
))
955 d_inode(dentry
)->i_flags
|= S_PRIVATE
;
957 err
= PTR_ERR(dentry
);
958 mutex_unlock(&d_inode(s
->s_root
)->i_mutex
);
964 * We need to take a copy of the mount flags since things like
965 * MS_RDONLY don't get set until *after* we're called.
966 * mount_flags != mount_options
968 int reiserfs_xattr_init(struct super_block
*s
, int mount_flags
)
971 struct dentry
*privroot
= REISERFS_SB(s
)->priv_root
;
973 err
= xattr_mount_check(s
);
977 if (d_really_is_negative(privroot
) && !(mount_flags
& MS_RDONLY
)) {
978 mutex_lock(&d_inode(s
->s_root
)->i_mutex
);
979 err
= create_privroot(REISERFS_SB(s
)->priv_root
);
980 mutex_unlock(&d_inode(s
->s_root
)->i_mutex
);
983 if (d_really_is_positive(privroot
)) {
984 s
->s_xattr
= reiserfs_xattr_handlers
;
985 mutex_lock(&d_inode(privroot
)->i_mutex
);
986 if (!REISERFS_SB(s
)->xattr_root
) {
987 struct dentry
*dentry
;
989 dentry
= lookup_one_len(XAROOT_NAME
, privroot
,
990 strlen(XAROOT_NAME
));
992 REISERFS_SB(s
)->xattr_root
= dentry
;
994 err
= PTR_ERR(dentry
);
996 mutex_unlock(&d_inode(privroot
)->i_mutex
);
1001 clear_bit(REISERFS_XATTRS_USER
, &REISERFS_SB(s
)->s_mount_opt
);
1002 clear_bit(REISERFS_POSIXACL
, &REISERFS_SB(s
)->s_mount_opt
);
1005 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
1006 if (reiserfs_posixacl(s
))
1007 s
->s_flags
|= MS_POSIXACL
;
1009 s
->s_flags
&= ~MS_POSIXACL
;