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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/reiserfs/xattr.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/reiserfs/xattr.c')
-rw-r--r--fs/reiserfs/xattr.c1450
1 files changed, 1450 insertions, 0 deletions
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
new file mode 100644
index 000000000000..45582fe8b466
--- /dev/null
+++ b/fs/reiserfs/xattr.c
@@ -0,0 +1,1450 @@
1/*
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.
30 */
31
32#include <linux/reiserfs_fs.h>
33#include <linux/dcache.h>
34#include <linux/namei.h>
35#include <linux/errno.h>
36#include <linux/fs.h>
37#include <linux/file.h>
38#include <linux/pagemap.h>
39#include <linux/xattr.h>
40#include <linux/reiserfs_xattr.h>
41#include <linux/reiserfs_acl.h>
42#include <linux/mbcache.h>
43#include <asm/uaccess.h>
44#include <asm/checksum.h>
45#include <linux/smp_lock.h>
46#include <linux/stat.h>
47#include <asm/semaphore.h>
48
49#define FL_READONLY 128
50#define FL_DIR_SEM_HELD 256
51#define PRIVROOT_NAME ".reiserfs_priv"
52#define XAROOT_NAME "xattrs"
53
54static struct reiserfs_xattr_handler *find_xattr_handler_prefix (const char *prefix);
55
56static struct dentry *
57create_xa_root (struct super_block *sb)
58{
59 struct dentry *privroot = dget (REISERFS_SB(sb)->priv_root);
60 struct dentry *xaroot;
61
62 /* This needs to be created at mount-time */
63 if (!privroot)
64 return ERR_PTR(-EOPNOTSUPP);
65
66 xaroot = lookup_one_len (XAROOT_NAME, privroot, strlen (XAROOT_NAME));
67 if (IS_ERR (xaroot)) {
68 goto out;
69 } else if (!xaroot->d_inode) {
70 int err;
71 down (&privroot->d_inode->i_sem);
72 err = privroot->d_inode->i_op->mkdir (privroot->d_inode, xaroot, 0700);
73 up (&privroot->d_inode->i_sem);
74
75 if (err) {
76 dput (xaroot);
77 dput (privroot);
78 return ERR_PTR (err);
79 }
80 REISERFS_SB(sb)->xattr_root = dget (xaroot);
81 }
82
83out:
84 dput (privroot);
85 return xaroot;
86}
87
88/* This will return a dentry, or error, refering to the xa root directory.
89 * If the xa root doesn't exist yet, the dentry will be returned without
90 * an associated inode. This dentry can be used with ->mkdir to create
91 * the xa directory. */
92static struct dentry *
93__get_xa_root (struct super_block *s)
94{
95 struct dentry *privroot = dget (REISERFS_SB(s)->priv_root);
96 struct dentry *xaroot = NULL;
97
98 if (IS_ERR (privroot) || !privroot)
99 return privroot;
100
101 xaroot = lookup_one_len (XAROOT_NAME, privroot, strlen (XAROOT_NAME));
102 if (IS_ERR (xaroot)) {
103 goto out;
104 } else if (!xaroot->d_inode) {
105 dput (xaroot);
106 xaroot = NULL;
107 goto out;
108 }
109
110 REISERFS_SB(s)->xattr_root = dget (xaroot);
111
112out:
113 dput (privroot);
114 return xaroot;
115}
116
117/* Returns the dentry (or NULL) referring to the root of the extended
118 * attribute directory tree. If it has already been retreived, it is used.
119 * Otherwise, we attempt to retreive it from disk. It may also return
120 * a pointer-encoded error.
121 */
122static inline struct dentry *
123get_xa_root (struct super_block *s)
124{
125 struct dentry *dentry = dget (REISERFS_SB(s)->xattr_root);
126
127 if (!dentry)
128 dentry = __get_xa_root (s);
129
130 return dentry;
131}
132
133/* Opens the directory corresponding to the inode's extended attribute store.
134 * If flags allow, the tree to the directory may be created. If creation is
135 * prohibited, -ENODATA is returned. */
136static struct dentry *
137open_xa_dir (const struct inode *inode, int flags)
138{
139 struct dentry *xaroot, *xadir;
140 char namebuf[17];
141
142 xaroot = get_xa_root (inode->i_sb);
143 if (IS_ERR (xaroot)) {
144 return xaroot;
145 } else if (!xaroot) {
146 if (flags == 0 || flags & XATTR_CREATE) {
147 xaroot = create_xa_root (inode->i_sb);
148 if (IS_ERR (xaroot))
149 return xaroot;
150 }
151 if (!xaroot)
152 return ERR_PTR (-ENODATA);
153 }
154
155 /* ok, we have xaroot open */
156
157 snprintf (namebuf, sizeof (namebuf), "%X.%X",
158 le32_to_cpu (INODE_PKEY (inode)->k_objectid),
159 inode->i_generation);
160 xadir = lookup_one_len (namebuf, xaroot, strlen (namebuf));
161 if (IS_ERR (xadir)) {
162 dput (xaroot);
163 return xadir;
164 }
165
166 if (!xadir->d_inode) {
167 int err;
168 if (flags == 0 || flags & XATTR_CREATE) {
169 /* Although there is nothing else trying to create this directory,
170 * another directory with the same hash may be created, so we need
171 * to protect against that */
172 err = xaroot->d_inode->i_op->mkdir (xaroot->d_inode, xadir, 0700);
173 if (err) {
174 dput (xaroot);
175 dput (xadir);
176 return ERR_PTR (err);
177 }
178 }
179 if (!xadir->d_inode) {
180 dput (xaroot);
181 dput (xadir);
182 return ERR_PTR (-ENODATA);
183 }
184 }
185
186 dput (xaroot);
187 return xadir;
188}
189
190/* Returns a dentry corresponding to a specific extended attribute file
191 * for the inode. If flags allow, the file is created. Otherwise, a
192 * valid or negative dentry, or an error is returned. */
193static struct dentry *
194get_xa_file_dentry (const struct inode *inode, const char *name, int flags)
195{
196 struct dentry *xadir, *xafile;
197 int err = 0;
198
199 xadir = open_xa_dir (inode, flags);
200 if (IS_ERR (xadir)) {
201 return ERR_PTR (PTR_ERR (xadir));
202 } else if (xadir && !xadir->d_inode) {
203 dput (xadir);
204 return ERR_PTR (-ENODATA);
205 }
206
207 xafile = lookup_one_len (name, xadir, strlen (name));
208 if (IS_ERR (xafile)) {
209 dput (xadir);
210 return ERR_PTR (PTR_ERR (xafile));
211 }
212
213 if (xafile->d_inode) { /* file exists */
214 if (flags & XATTR_CREATE) {
215 err = -EEXIST;
216 dput (xafile);
217 goto out;
218 }
219 } else if (flags & XATTR_REPLACE || flags & FL_READONLY) {
220 goto out;
221 } else {
222 /* inode->i_sem is down, so nothing else can try to create
223 * the same xattr */
224 err = xadir->d_inode->i_op->create (xadir->d_inode, xafile,
225 0700|S_IFREG, NULL);
226
227 if (err) {
228 dput (xafile);
229 goto out;
230 }
231 }
232
233out:
234 dput (xadir);
235 if (err)
236 xafile = ERR_PTR (err);
237 return xafile;
238}
239
240
241/* Opens a file pointer to the attribute associated with inode */
242static struct file *
243open_xa_file (const struct inode *inode, const char *name, int flags)
244{
245 struct dentry *xafile;
246 struct file *fp;
247
248 xafile = get_xa_file_dentry (inode, name, flags);
249 if (IS_ERR (xafile))
250 return ERR_PTR (PTR_ERR (xafile));
251 else if (!xafile->d_inode) {
252 dput (xafile);
253 return ERR_PTR (-ENODATA);
254 }
255
256 fp = dentry_open (xafile, NULL, O_RDWR);
257 /* dentry_open dputs the dentry if it fails */
258
259 return fp;
260}
261
262
263/*
264 * this is very similar to fs/reiserfs/dir.c:reiserfs_readdir, but
265 * we need to drop the path before calling the filldir struct. That
266 * would be a big performance hit to the non-xattr case, so I've copied
267 * the whole thing for now. --clm
268 *
269 * the big difference is that I go backwards through the directory,
270 * and don't mess with f->f_pos, but the idea is the same. Do some
271 * action on each and every entry in the directory.
272 *
273 * we're called with i_sem held, so there are no worries about the directory
274 * changing underneath us.
275 */
276static int __xattr_readdir(struct file * filp, void * dirent, filldir_t filldir)
277{
278 struct inode *inode = filp->f_dentry->d_inode;
279 struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
280 INITIALIZE_PATH (path_to_entry);
281 struct buffer_head * bh;
282 int entry_num;
283 struct item_head * ih, tmp_ih;
284 int search_res;
285 char * local_buf;
286 loff_t next_pos;
287 char small_buf[32] ; /* avoid kmalloc if we can */
288 struct reiserfs_de_head *deh;
289 int d_reclen;
290 char * d_name;
291 off_t d_off;
292 ino_t d_ino;
293 struct reiserfs_dir_entry de;
294
295
296 /* form key for search the next directory entry using f_pos field of
297 file structure */
298 next_pos = max_reiserfs_offset(inode);
299
300 while (1) {
301research:
302 if (next_pos <= DOT_DOT_OFFSET)
303 break;
304 make_cpu_key (&pos_key, inode, next_pos, TYPE_DIRENTRY, 3);
305
306 search_res = search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry, &de);
307 if (search_res == IO_ERROR) {
308 // FIXME: we could just skip part of directory which could
309 // not be read
310 pathrelse(&path_to_entry);
311 return -EIO;
312 }
313
314 if (search_res == NAME_NOT_FOUND)
315 de.de_entry_num--;
316
317 set_de_name_and_namelen(&de);
318 entry_num = de.de_entry_num;
319 deh = &(de.de_deh[entry_num]);
320
321 bh = de.de_bh;
322 ih = de.de_ih;
323
324 if (!is_direntry_le_ih(ih)) {
325 reiserfs_warning(inode->i_sb, "not direntry %h", ih);
326 break;
327 }
328 copy_item_head(&tmp_ih, ih);
329
330 /* we must have found item, that is item of this directory, */
331 RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
332 "vs-9000: found item %h does not match to dir we readdir %K",
333 ih, &pos_key);
334
335 if (deh_offset(deh) <= DOT_DOT_OFFSET) {
336 break;
337 }
338
339 /* look for the previous entry in the directory */
340 next_pos = deh_offset (deh) - 1;
341
342 if (!de_visible (deh))
343 /* it is hidden entry */
344 continue;
345
346 d_reclen = entry_length(bh, ih, entry_num);
347 d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
348 d_off = deh_offset (deh);
349 d_ino = deh_objectid (deh);
350
351 if (!d_name[d_reclen - 1])
352 d_reclen = strlen (d_name);
353
354 if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)){
355 /* too big to send back to VFS */
356 continue ;
357 }
358
359 /* Ignore the .reiserfs_priv entry */
360 if (reiserfs_xattrs (inode->i_sb) &&
361 !old_format_only(inode->i_sb) &&
362 deh_objectid (deh) == le32_to_cpu (INODE_PKEY(REISERFS_SB(inode->i_sb)->priv_root->d_inode)->k_objectid))
363 continue;
364
365 if (d_reclen <= 32) {
366 local_buf = small_buf ;
367 } else {
368 local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ;
369 if (!local_buf) {
370 pathrelse (&path_to_entry);
371 return -ENOMEM ;
372 }
373 if (item_moved (&tmp_ih, &path_to_entry)) {
374 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
375
376 /* sigh, must retry. Do this same offset again */
377 next_pos = d_off;
378 goto research;
379 }
380 }
381
382 // Note, that we copy name to user space via temporary
383 // buffer (local_buf) because filldir will block if
384 // user space buffer is swapped out. At that time
385 // entry can move to somewhere else
386 memcpy (local_buf, d_name, d_reclen);
387
388 /* the filldir function might need to start transactions,
389 * or do who knows what. Release the path now that we've
390 * copied all the important stuff out of the deh
391 */
392 pathrelse (&path_to_entry);
393
394 if (filldir (dirent, local_buf, d_reclen, d_off, d_ino,
395 DT_UNKNOWN) < 0) {
396 if (local_buf != small_buf) {
397 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
398 }
399 goto end;
400 }
401 if (local_buf != small_buf) {
402 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
403 }
404 } /* while */
405
406end:
407 pathrelse (&path_to_entry);
408 return 0;
409}
410
411/*
412 * this could be done with dedicated readdir ops for the xattr files,
413 * but I want to get something working asap
414 * this is stolen from vfs_readdir
415 *
416 */
417static
418int xattr_readdir(struct file *file, filldir_t filler, void *buf)
419{
420 struct inode *inode = file->f_dentry->d_inode;
421 int res = -ENOTDIR;
422 if (!file->f_op || !file->f_op->readdir)
423 goto out;
424 down(&inode->i_sem);
425// down(&inode->i_zombie);
426 res = -ENOENT;
427 if (!IS_DEADDIR(inode)) {
428 lock_kernel();
429 res = __xattr_readdir(file, buf, filler);
430 unlock_kernel();
431 }
432// up(&inode->i_zombie);
433 up(&inode->i_sem);
434out:
435 return res;
436}
437
438
439/* Internal operations on file data */
440static inline void
441reiserfs_put_page(struct page *page)
442{
443 kunmap(page);
444 page_cache_release(page);
445}
446
447static struct page *
448reiserfs_get_page(struct inode *dir, unsigned long n)
449{
450 struct address_space *mapping = dir->i_mapping;
451 struct page *page;
452 /* We can deadlock if we try to free dentries,
453 and an unlink/rmdir has just occured - GFP_NOFS avoids this */
454 mapping->flags = (mapping->flags & ~__GFP_BITS_MASK) | GFP_NOFS;
455 page = read_cache_page (mapping, n,
456 (filler_t*)mapping->a_ops->readpage, NULL);
457 if (!IS_ERR(page)) {
458 wait_on_page_locked(page);
459 kmap(page);
460 if (!PageUptodate(page))
461 goto fail;
462
463 if (PageError(page))
464 goto fail;
465 }
466 return page;
467
468fail:
469 reiserfs_put_page(page);
470 return ERR_PTR(-EIO);
471}
472
473static inline __u32
474xattr_hash (const char *msg, int len)
475{
476 return csum_partial (msg, len, 0);
477}
478
479/* Generic extended attribute operations that can be used by xa plugins */
480
481/*
482 * inode->i_sem: down
483 */
484int
485reiserfs_xattr_set (struct inode *inode, const char *name, const void *buffer,
486 size_t buffer_size, int flags)
487{
488 int err = 0;
489 struct file *fp;
490 struct page *page;
491 char *data;
492 struct address_space *mapping;
493 size_t file_pos = 0;
494 size_t buffer_pos = 0;
495 struct inode *xinode;
496 struct iattr newattrs;
497 __u32 xahash = 0;
498
499 if (IS_RDONLY (inode))
500 return -EROFS;
501
502 if (IS_IMMUTABLE (inode) || IS_APPEND (inode))
503 return -EPERM;
504
505 if (get_inode_sd_version (inode) == STAT_DATA_V1)
506 return -EOPNOTSUPP;
507
508 /* Empty xattrs are ok, they're just empty files, no hash */
509 if (buffer && buffer_size)
510 xahash = xattr_hash (buffer, buffer_size);
511
512open_file:
513 fp = open_xa_file (inode, name, flags);
514 if (IS_ERR (fp)) {
515 err = PTR_ERR (fp);
516 goto out;
517 }
518
519 xinode = fp->f_dentry->d_inode;
520 REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
521
522 /* we need to copy it off.. */
523 if (xinode->i_nlink > 1) {
524 fput(fp);
525 err = reiserfs_xattr_del (inode, name);
526 if (err < 0)
527 goto out;
528 /* We just killed the old one, we're not replacing anymore */
529 if (flags & XATTR_REPLACE)
530 flags &= ~XATTR_REPLACE;
531 goto open_file;
532 }
533
534 /* Resize it so we're ok to write there */
535 newattrs.ia_size = buffer_size;
536 newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
537 down (&xinode->i_sem);
538 err = notify_change(fp->f_dentry, &newattrs);
539 if (err)
540 goto out_filp;
541
542 mapping = xinode->i_mapping;
543 while (buffer_pos < buffer_size || buffer_pos == 0) {
544 size_t chunk;
545 size_t skip = 0;
546 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
547 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
548 chunk = PAGE_CACHE_SIZE;
549 else
550 chunk = buffer_size - buffer_pos;
551
552 page = reiserfs_get_page (xinode, file_pos >> PAGE_CACHE_SHIFT);
553 if (IS_ERR (page)) {
554 err = PTR_ERR (page);
555 goto out_filp;
556 }
557
558 lock_page (page);
559 data = page_address (page);
560
561 if (file_pos == 0) {
562 struct reiserfs_xattr_header *rxh;
563 skip = file_pos = sizeof (struct reiserfs_xattr_header);
564 if (chunk + skip > PAGE_CACHE_SIZE)
565 chunk = PAGE_CACHE_SIZE - skip;
566 rxh = (struct reiserfs_xattr_header *)data;
567 rxh->h_magic = cpu_to_le32 (REISERFS_XATTR_MAGIC);
568 rxh->h_hash = cpu_to_le32 (xahash);
569 }
570
571 err = mapping->a_ops->prepare_write (fp, page, page_offset,
572 page_offset + chunk + skip);
573 if (!err) {
574 if (buffer)
575 memcpy (data + skip, buffer + buffer_pos, chunk);
576 err = mapping->a_ops->commit_write (fp, page, page_offset,
577 page_offset + chunk + skip);
578 }
579 unlock_page (page);
580 reiserfs_put_page (page);
581 buffer_pos += chunk;
582 file_pos += chunk;
583 skip = 0;
584 if (err || buffer_size == 0 || !buffer)
585 break;
586 }
587
588 /* We can't mark the inode dirty if it's not hashed. This is the case
589 * when we're inheriting the default ACL. If we dirty it, the inode
590 * gets marked dirty, but won't (ever) make it onto the dirty list until
591 * it's synced explicitly to clear I_DIRTY. This is bad. */
592 if (!hlist_unhashed(&inode->i_hash)) {
593 inode->i_ctime = CURRENT_TIME_SEC;
594 mark_inode_dirty (inode);
595 }
596
597out_filp:
598 up (&xinode->i_sem);
599 fput(fp);
600
601out:
602 return err;
603}
604
605/*
606 * inode->i_sem: down
607 */
608int
609reiserfs_xattr_get (const struct inode *inode, const char *name, void *buffer,
610 size_t buffer_size)
611{
612 ssize_t err = 0;
613 struct file *fp;
614 size_t isize;
615 size_t file_pos = 0;
616 size_t buffer_pos = 0;
617 struct page *page;
618 struct inode *xinode;
619 __u32 hash = 0;
620
621 if (name == NULL)
622 return -EINVAL;
623
624 /* We can't have xattrs attached to v1 items since they don't have
625 * generation numbers */
626 if (get_inode_sd_version (inode) == STAT_DATA_V1)
627 return -EOPNOTSUPP;
628
629 fp = open_xa_file (inode, name, FL_READONLY);
630 if (IS_ERR (fp)) {
631 err = PTR_ERR (fp);
632 goto out;
633 }
634
635 xinode = fp->f_dentry->d_inode;
636 isize = xinode->i_size;
637 REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
638
639 /* Just return the size needed */
640 if (buffer == NULL) {
641 err = isize - sizeof (struct reiserfs_xattr_header);
642 goto out_dput;
643 }
644
645 if (buffer_size < isize - sizeof (struct reiserfs_xattr_header)) {
646 err = -ERANGE;
647 goto out_dput;
648 }
649
650 while (file_pos < isize) {
651 size_t chunk;
652 char *data;
653 size_t skip = 0;
654 if (isize - file_pos > PAGE_CACHE_SIZE)
655 chunk = PAGE_CACHE_SIZE;
656 else
657 chunk = isize - file_pos;
658
659 page = reiserfs_get_page (xinode, file_pos >> PAGE_CACHE_SHIFT);
660 if (IS_ERR (page)) {
661 err = PTR_ERR (page);
662 goto out_dput;
663 }
664
665 lock_page (page);
666 data = page_address (page);
667 if (file_pos == 0) {
668 struct reiserfs_xattr_header *rxh =
669 (struct reiserfs_xattr_header *)data;
670 skip = file_pos = sizeof (struct reiserfs_xattr_header);
671 chunk -= skip;
672 /* Magic doesn't match up.. */
673 if (rxh->h_magic != cpu_to_le32 (REISERFS_XATTR_MAGIC)) {
674 unlock_page (page);
675 reiserfs_put_page (page);
676 reiserfs_warning (inode->i_sb, "Invalid magic for xattr (%s) "
677 "associated with %k", name,
678 INODE_PKEY (inode));
679 err = -EIO;
680 goto out_dput;
681 }
682 hash = le32_to_cpu (rxh->h_hash);
683 }
684 memcpy (buffer + buffer_pos, data + skip, chunk);
685 unlock_page (page);
686 reiserfs_put_page (page);
687 file_pos += chunk;
688 buffer_pos += chunk;
689 skip = 0;
690 }
691 err = isize - sizeof (struct reiserfs_xattr_header);
692
693 if (xattr_hash (buffer, isize - sizeof (struct reiserfs_xattr_header)) != hash) {
694 reiserfs_warning (inode->i_sb, "Invalid hash for xattr (%s) associated "
695 "with %k", name, INODE_PKEY (inode));
696 err = -EIO;
697 }
698
699out_dput:
700 fput(fp);
701
702out:
703 return err;
704}
705
706static int
707__reiserfs_xattr_del (struct dentry *xadir, const char *name, int namelen)
708{
709 struct dentry *dentry;
710 struct inode *dir = xadir->d_inode;
711 int err = 0;
712
713 dentry = lookup_one_len (name, xadir, namelen);
714 if (IS_ERR (dentry)) {
715 err = PTR_ERR (dentry);
716 goto out;
717 } else if (!dentry->d_inode) {
718 err = -ENODATA;
719 goto out_file;
720 }
721
722 /* Skip directories.. */
723 if (S_ISDIR (dentry->d_inode->i_mode))
724 goto out_file;
725
726 if (!is_reiserfs_priv_object (dentry->d_inode)) {
727 reiserfs_warning (dir->i_sb, "OID %08x [%.*s/%.*s] doesn't have "
728 "priv flag set [parent is %sset].",
729 le32_to_cpu (INODE_PKEY (dentry->d_inode)->k_objectid),
730 xadir->d_name.len, xadir->d_name.name, namelen, name,
731 is_reiserfs_priv_object (xadir->d_inode) ? "" : "not ");
732 dput (dentry);
733 return -EIO;
734 }
735
736 err = dir->i_op->unlink (dir, dentry);
737 if (!err)
738 d_delete (dentry);
739
740out_file:
741 dput (dentry);
742
743out:
744 return err;
745}
746
747
748int
749reiserfs_xattr_del (struct inode *inode, const char *name)
750{
751 struct dentry *dir;
752 int err;
753
754 if (IS_RDONLY (inode))
755 return -EROFS;
756
757 dir = open_xa_dir (inode, FL_READONLY);
758 if (IS_ERR (dir)) {
759 err = PTR_ERR (dir);
760 goto out;
761 }
762
763 err = __reiserfs_xattr_del (dir, name, strlen (name));
764 dput (dir);
765
766 if (!err) {
767 inode->i_ctime = CURRENT_TIME_SEC;
768 mark_inode_dirty (inode);
769 }
770
771out:
772 return err;
773}
774
775/* The following are side effects of other operations that aren't explicitly
776 * modifying extended attributes. This includes operations such as permissions
777 * or ownership changes, object deletions, etc. */
778
779static int
780reiserfs_delete_xattrs_filler (void *buf, const char *name, int namelen,
781 loff_t offset, ino_t ino, unsigned int d_type)
782{
783 struct dentry *xadir = (struct dentry *)buf;
784
785 return __reiserfs_xattr_del (xadir, name, namelen);
786
787}
788
789/* This is called w/ inode->i_sem downed */
790int
791reiserfs_delete_xattrs (struct inode *inode)
792{
793 struct file *fp;
794 struct dentry *dir, *root;
795 int err = 0;
796
797 /* Skip out, an xattr has no xattrs associated with it */
798 if (is_reiserfs_priv_object (inode) ||
799 get_inode_sd_version (inode) == STAT_DATA_V1 ||
800 !reiserfs_xattrs(inode->i_sb))
801 {
802 return 0;
803 }
804 reiserfs_read_lock_xattrs (inode->i_sb);
805 dir = open_xa_dir (inode, FL_READONLY);
806 reiserfs_read_unlock_xattrs (inode->i_sb);
807 if (IS_ERR (dir)) {
808 err = PTR_ERR (dir);
809 goto out;
810 } else if (!dir->d_inode) {
811 dput (dir);
812 return 0;
813 }
814
815 fp = dentry_open (dir, NULL, O_RDWR);
816 if (IS_ERR (fp)) {
817 err = PTR_ERR (fp);
818 /* dentry_open dputs the dentry if it fails */
819 goto out;
820 }
821
822 lock_kernel ();
823 err = xattr_readdir (fp, reiserfs_delete_xattrs_filler, dir);
824 if (err) {
825 unlock_kernel ();
826 goto out_dir;
827 }
828
829 /* Leftovers besides . and .. -- that's not good. */
830 if (dir->d_inode->i_nlink <= 2) {
831 root = get_xa_root (inode->i_sb);
832 reiserfs_write_lock_xattrs (inode->i_sb);
833 err = vfs_rmdir (root->d_inode, dir);
834 reiserfs_write_unlock_xattrs (inode->i_sb);
835 dput (root);
836 } else {
837 reiserfs_warning (inode->i_sb,
838 "Couldn't remove all entries in directory");
839 }
840 unlock_kernel ();
841
842out_dir:
843 fput(fp);
844
845out:
846 if (!err)
847 REISERFS_I(inode)->i_flags = REISERFS_I(inode)->i_flags & ~i_has_xattr_dir;
848 return err;
849}
850
851struct reiserfs_chown_buf {
852 struct inode *inode;
853 struct dentry *xadir;
854 struct iattr *attrs;
855};
856
857/* XXX: If there is a better way to do this, I'd love to hear about it */
858static int
859reiserfs_chown_xattrs_filler (void *buf, const char *name, int namelen,
860 loff_t offset, ino_t ino, unsigned int d_type)
861{
862 struct reiserfs_chown_buf *chown_buf = (struct reiserfs_chown_buf *)buf;
863 struct dentry *xafile, *xadir = chown_buf->xadir;
864 struct iattr *attrs = chown_buf->attrs;
865 int err = 0;
866
867 xafile = lookup_one_len (name, xadir, namelen);
868 if (IS_ERR (xafile))
869 return PTR_ERR (xafile);
870 else if (!xafile->d_inode) {
871 dput (xafile);
872 return -ENODATA;
873 }
874
875 if (!S_ISDIR (xafile->d_inode->i_mode))
876 err = notify_change (xafile, attrs);
877 dput (xafile);
878
879 return err;
880}
881
882int
883reiserfs_chown_xattrs (struct inode *inode, struct iattr *attrs)
884{
885 struct file *fp;
886 struct dentry *dir;
887 int err = 0;
888 struct reiserfs_chown_buf buf;
889 unsigned int ia_valid = attrs->ia_valid;
890
891 /* Skip out, an xattr has no xattrs associated with it */
892 if (is_reiserfs_priv_object (inode) ||
893 get_inode_sd_version (inode) == STAT_DATA_V1 ||
894 !reiserfs_xattrs(inode->i_sb))
895 {
896 return 0;
897 }
898 reiserfs_read_lock_xattrs (inode->i_sb);
899 dir = open_xa_dir (inode, FL_READONLY);
900 reiserfs_read_unlock_xattrs (inode->i_sb);
901 if (IS_ERR (dir)) {
902 if (PTR_ERR (dir) != -ENODATA)
903 err = PTR_ERR (dir);
904 goto out;
905 } else if (!dir->d_inode) {
906 dput (dir);
907 goto out;
908 }
909
910 fp = dentry_open (dir, NULL, O_RDWR);
911 if (IS_ERR (fp)) {
912 err = PTR_ERR (fp);
913 /* dentry_open dputs the dentry if it fails */
914 goto out;
915 }
916
917 lock_kernel ();
918
919 attrs->ia_valid &= (ATTR_UID | ATTR_GID | ATTR_CTIME);
920 buf.xadir = dir;
921 buf.attrs = attrs;
922 buf.inode = inode;
923
924 err = xattr_readdir (fp, reiserfs_chown_xattrs_filler, &buf);
925 if (err) {
926 unlock_kernel ();
927 goto out_dir;
928 }
929
930 err = notify_change (dir, attrs);
931 unlock_kernel ();
932
933out_dir:
934 fput(fp);
935
936out:
937 attrs->ia_valid = ia_valid;
938 return err;
939}
940
941
942/* Actual operations that are exported to VFS-land */
943
944/*
945 * Inode operation getxattr()
946 * Preliminary locking: we down dentry->d_inode->i_sem
947 */
948ssize_t
949reiserfs_getxattr (struct dentry *dentry, const char *name, void *buffer,
950 size_t size)
951{
952 struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix (name);
953 int err;
954
955 if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
956 get_inode_sd_version (dentry->d_inode) == STAT_DATA_V1)
957 return -EOPNOTSUPP;
958
959 reiserfs_read_lock_xattr_i (dentry->d_inode);
960 reiserfs_read_lock_xattrs (dentry->d_sb);
961 err = xah->get (dentry->d_inode, name, buffer, size);
962 reiserfs_read_unlock_xattrs (dentry->d_sb);
963 reiserfs_read_unlock_xattr_i (dentry->d_inode);
964 return err;
965}
966
967
968/*
969 * Inode operation setxattr()
970 *
971 * dentry->d_inode->i_sem down
972 */
973int
974reiserfs_setxattr (struct dentry *dentry, const char *name, const void *value,
975 size_t size, int flags)
976{
977 struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix (name);
978 int err;
979 int lock;
980
981 if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
982 get_inode_sd_version (dentry->d_inode) == STAT_DATA_V1)
983 return -EOPNOTSUPP;
984
985 if (IS_RDONLY (dentry->d_inode))
986 return -EROFS;
987
988 if (IS_IMMUTABLE (dentry->d_inode) || IS_APPEND (dentry->d_inode))
989 return -EROFS;
990
991 reiserfs_write_lock_xattr_i (dentry->d_inode);
992 lock = !has_xattr_dir (dentry->d_inode);
993 if (lock)
994 reiserfs_write_lock_xattrs (dentry->d_sb);
995 else
996 reiserfs_read_lock_xattrs (dentry->d_sb);
997 err = xah->set (dentry->d_inode, name, value, size, flags);
998 if (lock)
999 reiserfs_write_unlock_xattrs (dentry->d_sb);
1000 else
1001 reiserfs_read_unlock_xattrs (dentry->d_sb);
1002 reiserfs_write_unlock_xattr_i (dentry->d_inode);
1003 return err;
1004}
1005
1006/*
1007 * Inode operation removexattr()
1008 *
1009 * dentry->d_inode->i_sem down
1010 */
1011int
1012reiserfs_removexattr (struct dentry *dentry, const char *name)
1013{
1014 int err;
1015 struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix (name);
1016
1017 if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
1018 get_inode_sd_version (dentry->d_inode) == STAT_DATA_V1)
1019 return -EOPNOTSUPP;
1020
1021 if (IS_RDONLY (dentry->d_inode))
1022 return -EROFS;
1023
1024 if (IS_IMMUTABLE (dentry->d_inode) || IS_APPEND (dentry->d_inode))
1025 return -EPERM;
1026
1027 reiserfs_write_lock_xattr_i (dentry->d_inode);
1028 reiserfs_read_lock_xattrs (dentry->d_sb);
1029
1030 /* Deletion pre-operation */
1031 if (xah->del) {
1032 err = xah->del (dentry->d_inode, name);
1033 if (err)
1034 goto out;
1035 }
1036
1037 err = reiserfs_xattr_del (dentry->d_inode, name);
1038
1039 dentry->d_inode->i_ctime = CURRENT_TIME_SEC;
1040 mark_inode_dirty (dentry->d_inode);
1041
1042out:
1043 reiserfs_read_unlock_xattrs (dentry->d_sb);
1044 reiserfs_write_unlock_xattr_i (dentry->d_inode);
1045 return err;
1046}
1047
1048
1049/* This is what filldir will use:
1050 * r_pos will always contain the amount of space required for the entire
1051 * list. If r_pos becomes larger than r_size, we need more space and we
1052 * return an error indicating this. If r_pos is less than r_size, then we've
1053 * filled the buffer successfully and we return success */
1054struct reiserfs_listxattr_buf {
1055 int r_pos;
1056 int r_size;
1057 char *r_buf;
1058 struct inode *r_inode;
1059};
1060
1061static int
1062reiserfs_listxattr_filler (void *buf, const char *name, int namelen,
1063 loff_t offset, ino_t ino, unsigned int d_type)
1064{
1065 struct reiserfs_listxattr_buf *b = (struct reiserfs_listxattr_buf *)buf;
1066 int len = 0;
1067 if (name[0] != '.' || (namelen != 1 && (name[1] != '.' || namelen != 2))) {
1068 struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix (name);
1069 if (!xah) return 0; /* Unsupported xattr name, skip it */
1070
1071 /* We call ->list() twice because the operation isn't required to just
1072 * return the name back - we want to make sure we have enough space */
1073 len += xah->list (b->r_inode, name, namelen, NULL);
1074
1075 if (len) {
1076 if (b->r_pos + len + 1 <= b->r_size) {
1077 char *p = b->r_buf + b->r_pos;
1078 p += xah->list (b->r_inode, name, namelen, p);
1079 *p++ = '\0';
1080 }
1081 b->r_pos += len + 1;
1082 }
1083 }
1084
1085 return 0;
1086}
1087/*
1088 * Inode operation listxattr()
1089 *
1090 * Preliminary locking: we down dentry->d_inode->i_sem
1091 */
1092ssize_t
1093reiserfs_listxattr (struct dentry *dentry, char *buffer, size_t size)
1094{
1095 struct file *fp;
1096 struct dentry *dir;
1097 int err = 0;
1098 struct reiserfs_listxattr_buf buf;
1099
1100 if (!dentry->d_inode)
1101 return -EINVAL;
1102
1103 if (!reiserfs_xattrs(dentry->d_sb) ||
1104 get_inode_sd_version (dentry->d_inode) == STAT_DATA_V1)
1105 return -EOPNOTSUPP;
1106
1107 reiserfs_read_lock_xattr_i (dentry->d_inode);
1108 reiserfs_read_lock_xattrs (dentry->d_sb);
1109 dir = open_xa_dir (dentry->d_inode, FL_READONLY);
1110 reiserfs_read_unlock_xattrs (dentry->d_sb);
1111 if (IS_ERR (dir)) {
1112 err = PTR_ERR (dir);
1113 if (err == -ENODATA)
1114 err = 0; /* Not an error if there aren't any xattrs */
1115 goto out;
1116 }
1117
1118 fp = dentry_open (dir, NULL, O_RDWR);
1119 if (IS_ERR (fp)) {
1120 err = PTR_ERR (fp);
1121 /* dentry_open dputs the dentry if it fails */
1122 goto out;
1123 }
1124
1125 buf.r_buf = buffer;
1126 buf.r_size = buffer ? size : 0;
1127 buf.r_pos = 0;
1128 buf.r_inode = dentry->d_inode;
1129
1130 REISERFS_I(dentry->d_inode)->i_flags |= i_has_xattr_dir;
1131
1132 err = xattr_readdir (fp, reiserfs_listxattr_filler, &buf);
1133 if (err)
1134 goto out_dir;
1135
1136 if (buf.r_pos > buf.r_size && buffer != NULL)
1137 err = -ERANGE;
1138 else
1139 err = buf.r_pos;
1140
1141out_dir:
1142 fput(fp);
1143
1144out:
1145 reiserfs_read_unlock_xattr_i (dentry->d_inode);
1146 return err;
1147}
1148
1149/* This is the implementation for the xattr plugin infrastructure */
1150static struct list_head xattr_handlers = LIST_HEAD_INIT (xattr_handlers);
1151static DEFINE_RWLOCK(handler_lock);
1152
1153static struct reiserfs_xattr_handler *
1154find_xattr_handler_prefix (const char *prefix)
1155{
1156 struct reiserfs_xattr_handler *xah = NULL;
1157 struct list_head *p;
1158
1159 read_lock (&handler_lock);
1160 list_for_each (p, &xattr_handlers) {
1161 xah = list_entry (p, struct reiserfs_xattr_handler, handlers);
1162 if (strncmp (xah->prefix, prefix, strlen (xah->prefix)) == 0)
1163 break;
1164 xah = NULL;
1165 }
1166
1167 read_unlock (&handler_lock);
1168 return xah;
1169}
1170
1171static void
1172__unregister_handlers (void)
1173{
1174 struct reiserfs_xattr_handler *xah;
1175 struct list_head *p, *tmp;
1176
1177 list_for_each_safe (p, tmp, &xattr_handlers) {
1178 xah = list_entry (p, struct reiserfs_xattr_handler, handlers);
1179 if (xah->exit)
1180 xah->exit();
1181
1182 list_del_init (p);
1183 }
1184 INIT_LIST_HEAD (&xattr_handlers);
1185}
1186
1187int __init
1188reiserfs_xattr_register_handlers (void)
1189{
1190 int err = 0;
1191 struct reiserfs_xattr_handler *xah;
1192 struct list_head *p;
1193
1194 write_lock (&handler_lock);
1195
1196 /* If we're already initialized, nothing to do */
1197 if (!list_empty (&xattr_handlers)) {
1198 write_unlock (&handler_lock);
1199 return 0;
1200 }
1201
1202 /* Add the handlers */
1203 list_add_tail (&user_handler.handlers, &xattr_handlers);
1204 list_add_tail (&trusted_handler.handlers, &xattr_handlers);
1205#ifdef CONFIG_REISERFS_FS_SECURITY
1206 list_add_tail (&security_handler.handlers, &xattr_handlers);
1207#endif
1208#ifdef CONFIG_REISERFS_FS_POSIX_ACL
1209 list_add_tail (&posix_acl_access_handler.handlers, &xattr_handlers);
1210 list_add_tail (&posix_acl_default_handler.handlers, &xattr_handlers);
1211#endif
1212
1213 /* Run initializers, if available */
1214 list_for_each (p, &xattr_handlers) {
1215 xah = list_entry (p, struct reiserfs_xattr_handler, handlers);
1216 if (xah->init) {
1217 err = xah->init ();
1218 if (err) {
1219 list_del_init (p);
1220 break;
1221 }
1222 }
1223 }
1224
1225 /* Clean up other handlers, if any failed */
1226 if (err)
1227 __unregister_handlers ();
1228
1229 write_unlock (&handler_lock);
1230 return err;
1231}
1232
1233void
1234reiserfs_xattr_unregister_handlers (void)
1235{
1236 write_lock (&handler_lock);
1237 __unregister_handlers ();
1238 write_unlock (&handler_lock);
1239}
1240
1241/* This will catch lookups from the fs root to .reiserfs_priv */
1242static int
1243xattr_lookup_poison (struct dentry *dentry, struct qstr *q1, struct qstr *name)
1244{
1245 struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
1246 if (name->len == priv_root->d_name.len &&
1247 name->hash == priv_root->d_name.hash &&
1248 !memcmp (name->name, priv_root->d_name.name, name->len)) {
1249 return -ENOENT;
1250 } else if (q1->len == name->len &&
1251 !memcmp(q1->name, name->name, name->len))
1252 return 0;
1253 return 1;
1254}
1255
1256static struct dentry_operations xattr_lookup_poison_ops = {
1257 .d_compare = xattr_lookup_poison,
1258};
1259
1260
1261/* We need to take a copy of the mount flags since things like
1262 * MS_RDONLY don't get set until *after* we're called.
1263 * mount_flags != mount_options */
1264int
1265reiserfs_xattr_init (struct super_block *s, int mount_flags)
1266{
1267 int err = 0;
1268
1269 /* We need generation numbers to ensure that the oid mapping is correct
1270 * v3.5 filesystems don't have them. */
1271 if (!old_format_only (s)) {
1272 set_bit (REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
1273 } else if (reiserfs_xattrs_optional (s)) {
1274 /* Old format filesystem, but optional xattrs have been enabled
1275 * at mount time. Error out. */
1276 reiserfs_warning (s, "xattrs/ACLs not supported on pre v3.6 "
1277 "format filesystem. Failing mount.");
1278 err = -EOPNOTSUPP;
1279 goto error;
1280 } else {
1281 /* Old format filesystem, but no optional xattrs have been enabled. This
1282 * means we silently disable xattrs on the filesystem. */
1283 clear_bit (REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
1284 }
1285
1286 /* If we don't have the privroot located yet - go find it */
1287 if (reiserfs_xattrs (s) && !REISERFS_SB(s)->priv_root) {
1288 struct dentry *dentry;
1289 dentry = lookup_one_len (PRIVROOT_NAME, s->s_root,
1290 strlen (PRIVROOT_NAME));
1291 if (!IS_ERR (dentry)) {
1292 if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) {
1293 struct inode *inode = dentry->d_parent->d_inode;
1294 down (&inode->i_sem);
1295 err = inode->i_op->mkdir (inode, dentry, 0700);
1296 up (&inode->i_sem);
1297 if (err) {
1298 dput (dentry);
1299 dentry = NULL;
1300 }
1301
1302 if (dentry && dentry->d_inode)
1303 reiserfs_warning (s, "Created %s on %s - reserved for "
1304 "xattr storage.", PRIVROOT_NAME,
1305 reiserfs_bdevname (inode->i_sb));
1306 } else if (!dentry->d_inode) {
1307 dput (dentry);
1308 dentry = NULL;
1309 }
1310 } else
1311 err = PTR_ERR (dentry);
1312
1313 if (!err && dentry) {
1314 s->s_root->d_op = &xattr_lookup_poison_ops;
1315 reiserfs_mark_inode_private (dentry->d_inode);
1316 REISERFS_SB(s)->priv_root = dentry;
1317 } else if (!(mount_flags & MS_RDONLY)) { /* xattrs are unavailable */
1318 /* If we're read-only it just means that the dir hasn't been
1319 * created. Not an error -- just no xattrs on the fs. We'll
1320 * check again if we go read-write */
1321 reiserfs_warning (s, "xattrs/ACLs enabled and couldn't "
1322 "find/create .reiserfs_priv. Failing mount.");
1323 err = -EOPNOTSUPP;
1324 }
1325 }
1326
1327error:
1328 /* This is only nonzero if there was an error initializing the xattr
1329 * directory or if there is a condition where we don't support them. */
1330 if (err) {
1331 clear_bit (REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
1332 clear_bit (REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
1333 clear_bit (REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
1334 }
1335
1336 /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
1337 s->s_flags = s->s_flags & ~MS_POSIXACL;
1338 if (reiserfs_posixacl (s))
1339 s->s_flags |= MS_POSIXACL;
1340
1341 return err;
1342}
1343
1344static int
1345__reiserfs_permission (struct inode *inode, int mask, struct nameidata *nd,
1346 int need_lock)
1347{
1348 umode_t mode = inode->i_mode;
1349
1350 if (mask & MAY_WRITE) {
1351 /*
1352 * Nobody gets write access to a read-only fs.
1353 */
1354 if (IS_RDONLY(inode) &&
1355 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
1356 return -EROFS;
1357
1358 /*
1359 * Nobody gets write access to an immutable file.
1360 */
1361 if (IS_IMMUTABLE(inode))
1362 return -EACCES;
1363 }
1364
1365 /* We don't do permission checks on the internal objects.
1366 * Permissions are determined by the "owning" object. */
1367 if (is_reiserfs_priv_object (inode))
1368 return 0;
1369
1370 if (current->fsuid == inode->i_uid) {
1371 mode >>= 6;
1372#ifdef CONFIG_REISERFS_FS_POSIX_ACL
1373 } else if (reiserfs_posixacl(inode->i_sb) &&
1374 get_inode_sd_version (inode) != STAT_DATA_V1) {
1375 struct posix_acl *acl;
1376
1377 /* ACL can't contain additional permissions if
1378 the ACL_MASK entry is 0 */
1379 if (!(mode & S_IRWXG))
1380 goto check_groups;
1381
1382 if (need_lock) {
1383 reiserfs_read_lock_xattr_i (inode);
1384 reiserfs_read_lock_xattrs (inode->i_sb);
1385 }
1386 acl = reiserfs_get_acl (inode, ACL_TYPE_ACCESS);
1387 if (need_lock) {
1388 reiserfs_read_unlock_xattrs (inode->i_sb);
1389 reiserfs_read_unlock_xattr_i (inode);
1390 }
1391 if (IS_ERR (acl)) {
1392 if (PTR_ERR (acl) == -ENODATA)
1393 goto check_groups;
1394 return PTR_ERR (acl);
1395 }
1396
1397 if (acl) {
1398 int err = posix_acl_permission (inode, acl, mask);
1399 posix_acl_release (acl);
1400 if (err == -EACCES) {
1401 goto check_capabilities;
1402 }
1403 return err;
1404 } else {
1405 goto check_groups;
1406 }
1407#endif
1408 } else {
1409check_groups:
1410 if (in_group_p(inode->i_gid))
1411 mode >>= 3;
1412 }
1413
1414 /*
1415 * If the DACs are ok we don't need any capability check.
1416 */
1417 if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
1418 return 0;
1419
1420check_capabilities:
1421 /*
1422 * Read/write DACs are always overridable.
1423 * Executable DACs are overridable if at least one exec bit is set.
1424 */
1425 if (!(mask & MAY_EXEC) ||
1426 (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
1427 if (capable(CAP_DAC_OVERRIDE))
1428 return 0;
1429
1430 /*
1431 * Searching includes executable on directories, else just read.
1432 */
1433 if (mask == MAY_READ || (S_ISDIR(inode->i_mode) && !(mask & MAY_WRITE)))
1434 if (capable(CAP_DAC_READ_SEARCH))
1435 return 0;
1436
1437 return -EACCES;
1438}
1439
1440int
1441reiserfs_permission (struct inode *inode, int mask, struct nameidata *nd)
1442{
1443 return __reiserfs_permission (inode, mask, nd, 1);
1444}
1445
1446int
1447reiserfs_permission_locked (struct inode *inode, int mask, struct nameidata *nd)
1448{
1449 return __reiserfs_permission (inode, mask, nd, 0);
1450}