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36#include "reiserfs.h"
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>
42#include <linux/fs.h>
43#include <linux/file.h>
44#include <linux/pagemap.h>
45#include <linux/xattr.h>
46#include "xattr.h"
47#include "acl.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>
54
55#define PRIVROOT_NAME ".reiserfs_priv"
56#define XAROOT_NAME "xattrs"
57
58
59
60
61
62
63
64#ifdef CONFIG_REISERFS_FS_XATTR
65static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
66{
67 BUG_ON(!mutex_is_locked(&dir->i_mutex));
68 return dir->i_op->create(dir, dentry, mode, true);
69}
70#endif
71
72static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
73{
74 BUG_ON(!mutex_is_locked(&dir->i_mutex));
75 return dir->i_op->mkdir(dir, dentry, mode);
76}
77
78
79
80
81
82
83
84static int xattr_unlink(struct inode *dir, struct dentry *dentry)
85{
86 int error;
87
88 BUG_ON(!mutex_is_locked(&dir->i_mutex));
89
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);
93
94 if (!error)
95 d_delete(dentry);
96 return error;
97}
98
99static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
100{
101 int error;
102
103 BUG_ON(!mutex_is_locked(&dir->i_mutex));
104
105 mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_CHILD);
106 error = dir->i_op->rmdir(dir, dentry);
107 if (!error)
108 d_inode(dentry)->i_flags |= S_DEAD;
109 mutex_unlock(&d_inode(dentry)->i_mutex);
110 if (!error)
111 d_delete(dentry);
112
113 return error;
114}
115
116#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
117
118static struct dentry *open_xa_root(struct super_block *sb, int flags)
119{
120 struct dentry *privroot = REISERFS_SB(sb)->priv_root;
121 struct dentry *xaroot;
122
123 if (d_really_is_negative(privroot))
124 return ERR_PTR(-ENODATA);
125
126 mutex_lock_nested(&d_inode(privroot)->i_mutex, I_MUTEX_XATTR);
127
128 xaroot = dget(REISERFS_SB(sb)->xattr_root);
129 if (!xaroot)
130 xaroot = ERR_PTR(-ENODATA);
131 else if (d_really_is_negative(xaroot)) {
132 int err = -ENODATA;
133
134 if (xattr_may_create(flags))
135 err = xattr_mkdir(d_inode(privroot), xaroot, 0700);
136 if (err) {
137 dput(xaroot);
138 xaroot = ERR_PTR(err);
139 }
140 }
141
142 mutex_unlock(&d_inode(privroot)->i_mutex);
143 return xaroot;
144}
145
146static struct dentry *open_xa_dir(const struct inode *inode, int flags)
147{
148 struct dentry *xaroot, *xadir;
149 char namebuf[17];
150
151 xaroot = open_xa_root(inode->i_sb, flags);
152 if (IS_ERR(xaroot))
153 return xaroot;
154
155 snprintf(namebuf, sizeof(namebuf), "%X.%X",
156 le32_to_cpu(INODE_PKEY(inode)->k_objectid),
157 inode->i_generation);
158
159 mutex_lock_nested(&d_inode(xaroot)->i_mutex, I_MUTEX_XATTR);
160
161 xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
162 if (!IS_ERR(xadir) && d_really_is_negative(xadir)) {
163 int err = -ENODATA;
164
165 if (xattr_may_create(flags))
166 err = xattr_mkdir(d_inode(xaroot), xadir, 0700);
167 if (err) {
168 dput(xadir);
169 xadir = ERR_PTR(err);
170 }
171 }
172
173 mutex_unlock(&d_inode(xaroot)->i_mutex);
174 dput(xaroot);
175 return xadir;
176}
177
178
179
180
181
182
183struct reiserfs_dentry_buf {
184 struct dir_context ctx;
185 struct dentry *xadir;
186 int count;
187 struct dentry *dentries[8];
188};
189
190static int
191fill_with_dentries(struct dir_context *ctx, const char *name, int namelen,
192 loff_t offset, u64 ino, unsigned int d_type)
193{
194 struct reiserfs_dentry_buf *dbuf =
195 container_of(ctx, struct reiserfs_dentry_buf, ctx);
196 struct dentry *dentry;
197
198 WARN_ON_ONCE(!mutex_is_locked(&d_inode(dbuf->xadir)->i_mutex));
199
200 if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
201 return -ENOSPC;
202
203 if (name[0] == '.' && (namelen < 2 ||
204 (namelen == 2 && name[1] == '.')))
205 return 0;
206
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
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);
216 dput(dentry);
217 return -EIO;
218 }
219
220 dbuf->dentries[dbuf->count++] = dentry;
221 return 0;
222}
223
224static void
225cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
226{
227 int i;
228
229 for (i = 0; i < buf->count; i++)
230 if (buf->dentries[i])
231 dput(buf->dentries[i]);
232}
233
234static int reiserfs_for_each_xattr(struct inode *inode,
235 int (*action)(struct dentry *, void *),
236 void *data)
237{
238 struct dentry *dir;
239 int i, err = 0;
240 struct reiserfs_dentry_buf buf = {
241 .ctx.actor = fill_with_dentries,
242 };
243
244
245 if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
246 return 0;
247
248 dir = open_xa_dir(inode, XATTR_REPLACE);
249 if (IS_ERR(dir)) {
250 err = PTR_ERR(dir);
251 goto out;
252 } else if (d_really_is_negative(dir)) {
253 err = 0;
254 goto out_dir;
255 }
256
257 mutex_lock_nested(&d_inode(dir)->i_mutex, I_MUTEX_XATTR);
258
259 buf.xadir = dir;
260 while (1) {
261 err = reiserfs_readdir_inode(d_inode(dir), &buf.ctx);
262 if (err)
263 break;
264 if (!buf.count)
265 break;
266 for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {
267 struct dentry *dentry = buf.dentries[i];
268
269 if (!d_is_dir(dentry))
270 err = action(dentry, data);
271
272 dput(dentry);
273 buf.dentries[i] = NULL;
274 }
275 if (err)
276 break;
277 buf.count = 0;
278 }
279 mutex_unlock(&d_inode(dir)->i_mutex);
280
281 cleanup_dentry_buf(&buf);
282
283 if (!err) {
284
285
286
287
288
289
290
291 int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
292 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
293 struct reiserfs_transaction_handle th;
294
295 reiserfs_write_lock(inode->i_sb);
296 err = journal_begin(&th, inode->i_sb, blocks);
297 reiserfs_write_unlock(inode->i_sb);
298 if (!err) {
299 int jerror;
300
301 mutex_lock_nested(&d_inode(dir->d_parent)->i_mutex,
302 I_MUTEX_XATTR);
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);
308 err = jerror ?: err;
309 }
310 }
311out_dir:
312 dput(dir);
313out:
314
315 if (err == -ENODATA)
316 err = 0;
317 return err;
318}
319
320static int delete_one_xattr(struct dentry *dentry, void *data)
321{
322 struct inode *dir = d_inode(dentry->d_parent);
323
324
325 if (d_is_dir(dentry))
326 return xattr_rmdir(dir, dentry);
327
328 return xattr_unlink(dir, dentry);
329}
330
331static int chown_one_xattr(struct dentry *dentry, void *data)
332{
333 struct iattr *attrs = data;
334 int ia_valid = attrs->ia_valid;
335 int err;
336
337
338
339
340
341
342 attrs->ia_valid &= (ATTR_UID|ATTR_GID);
343 err = reiserfs_setattr(dentry, attrs);
344 attrs->ia_valid = ia_valid;
345
346 return err;
347}
348
349
350int reiserfs_delete_xattrs(struct inode *inode)
351{
352 int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
353
354 if (err)
355 reiserfs_warning(inode->i_sb, "jdm-20004",
356 "Couldn't delete all xattrs (%d)\n", err);
357 return err;
358}
359
360
361int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
362{
363 int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
364
365 if (err)
366 reiserfs_warning(inode->i_sb, "jdm-20007",
367 "Couldn't chown all xattrs (%d)\n", err);
368 return err;
369}
370
371#ifdef CONFIG_REISERFS_FS_XATTR
372
373
374
375
376
377static struct dentry *xattr_lookup(struct inode *inode, const char *name,
378 int flags)
379{
380 struct dentry *xadir, *xafile;
381 int err = 0;
382
383 xadir = open_xa_dir(inode, flags);
384 if (IS_ERR(xadir))
385 return ERR_CAST(xadir);
386
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);
391 goto out;
392 }
393
394 if (d_really_is_positive(xafile) && (flags & XATTR_CREATE))
395 err = -EEXIST;
396
397 if (d_really_is_negative(xafile)) {
398 err = -ENODATA;
399 if (xattr_may_create(flags))
400 err = xattr_create(d_inode(xadir), xafile,
401 0700|S_IFREG);
402 }
403
404 if (err)
405 dput(xafile);
406out:
407 mutex_unlock(&d_inode(xadir)->i_mutex);
408 dput(xadir);
409 if (err)
410 return ERR_PTR(err);
411 return xafile;
412}
413
414
415static inline void reiserfs_put_page(struct page *page)
416{
417 kunmap(page);
418 page_cache_release(page);
419}
420
421static struct page *reiserfs_get_page(struct inode *dir, size_t n)
422{
423 struct address_space *mapping = dir->i_mapping;
424 struct page *page;
425
426
427
428
429 mapping_set_gfp_mask(mapping, GFP_NOFS);
430 page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
431 if (!IS_ERR(page)) {
432 kmap(page);
433 if (PageError(page))
434 goto fail;
435 }
436 return page;
437
438fail:
439 reiserfs_put_page(page);
440 return ERR_PTR(-EIO);
441}
442
443static inline __u32 xattr_hash(const char *msg, int len)
444{
445 return csum_partial(msg, len, 0);
446}
447
448int reiserfs_commit_write(struct file *f, struct page *page,
449 unsigned from, unsigned to);
450
451static void update_ctime(struct inode *inode)
452{
453 struct timespec now = current_fs_time(inode->i_sb);
454
455 if (inode_unhashed(inode) || !inode->i_nlink ||
456 timespec_equal(&inode->i_ctime, &now))
457 return;
458
459 inode->i_ctime = CURRENT_TIME_SEC;
460 mark_inode_dirty(inode);
461}
462
463static int lookup_and_delete_xattr(struct inode *inode, const char *name)
464{
465 int err = 0;
466 struct dentry *dentry, *xadir;
467
468 xadir = open_xa_dir(inode, XATTR_REPLACE);
469 if (IS_ERR(xadir))
470 return PTR_ERR(xadir);
471
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);
476 goto out_dput;
477 }
478
479 if (d_really_is_positive(dentry)) {
480 err = xattr_unlink(d_inode(xadir), dentry);
481 update_ctime(inode);
482 }
483
484 dput(dentry);
485out_dput:
486 mutex_unlock(&d_inode(xadir)->i_mutex);
487 dput(xadir);
488 return err;
489}
490
491
492
493
494
495
496
497int
498reiserfs_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)
501{
502 int err = 0;
503 struct dentry *dentry;
504 struct page *page;
505 char *data;
506 size_t file_pos = 0;
507 size_t buffer_pos = 0;
508 size_t new_size;
509 __u32 xahash = 0;
510
511 if (get_inode_sd_version(inode) == STAT_DATA_V1)
512 return -EOPNOTSUPP;
513
514 if (!buffer) {
515 err = lookup_and_delete_xattr(inode, name);
516 return err;
517 }
518
519 dentry = xattr_lookup(inode, name, flags);
520 if (IS_ERR(dentry))
521 return PTR_ERR(dentry);
522
523 down_write(&REISERFS_I(inode)->i_xattr_sem);
524
525 xahash = xattr_hash(buffer, buffer_size);
526 while (buffer_pos < buffer_size || buffer_pos == 0) {
527 size_t chunk;
528 size_t skip = 0;
529 size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
530
531 if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
532 chunk = PAGE_CACHE_SIZE;
533 else
534 chunk = buffer_size - buffer_pos;
535
536 page = reiserfs_get_page(d_inode(dentry), file_pos);
537 if (IS_ERR(page)) {
538 err = PTR_ERR(page);
539 goto out_unlock;
540 }
541
542 lock_page(page);
543 data = page_address(page);
544
545 if (file_pos == 0) {
546 struct reiserfs_xattr_header *rxh;
547
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);
554 }
555
556 reiserfs_write_lock(inode->i_sb);
557 err = __reiserfs_write_begin(page, page_offset, chunk + skip);
558 if (!err) {
559 if (buffer)
560 memcpy(data + skip, buffer + buffer_pos, chunk);
561 err = reiserfs_commit_write(NULL, page, page_offset,
562 page_offset + chunk +
563 skip);
564 }
565 reiserfs_write_unlock(inode->i_sb);
566 unlock_page(page);
567 reiserfs_put_page(page);
568 buffer_pos += chunk;
569 file_pos += chunk;
570 skip = 0;
571 if (err || buffer_size == 0 || !buffer)
572 break;
573 }
574
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),
579 .ia_size = new_size,
580 .ia_valid = ATTR_SIZE | ATTR_CTIME,
581 };
582
583 mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_XATTR);
584 inode_dio_wait(d_inode(dentry));
585
586 err = reiserfs_setattr(dentry, &newattrs);
587 mutex_unlock(&d_inode(dentry)->i_mutex);
588 } else
589 update_ctime(inode);
590out_unlock:
591 up_write(&REISERFS_I(inode)->i_xattr_sem);
592 dput(dentry);
593 return err;
594}
595
596
597int reiserfs_xattr_set(struct inode *inode, const char *name,
598 const void *buffer, size_t buffer_size, int flags)
599{
600
601 struct reiserfs_transaction_handle th;
602 int error, error2;
603 size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
604
605 if (!(flags & XATTR_REPLACE))
606 jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
607
608 reiserfs_write_lock(inode->i_sb);
609 error = journal_begin(&th, inode->i_sb, jbegin_count);
610 reiserfs_write_unlock(inode->i_sb);
611 if (error) {
612 return error;
613 }
614
615 error = reiserfs_xattr_set_handle(&th, inode, name,
616 buffer, buffer_size, flags);
617
618 reiserfs_write_lock(inode->i_sb);
619 error2 = journal_end(&th);
620 reiserfs_write_unlock(inode->i_sb);
621 if (error == 0)
622 error = error2;
623
624 return error;
625}
626
627
628
629
630int
631reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
632 size_t buffer_size)
633{
634 ssize_t err = 0;
635 struct dentry *dentry;
636 size_t isize;
637 size_t file_pos = 0;
638 size_t buffer_pos = 0;
639 struct page *page;
640 __u32 hash = 0;
641
642 if (name == NULL)
643 return -EINVAL;
644
645
646
647
648
649 if (get_inode_sd_version(inode) == STAT_DATA_V1)
650 return -EOPNOTSUPP;
651
652 dentry = xattr_lookup(inode, name, XATTR_REPLACE);
653 if (IS_ERR(dentry)) {
654 err = PTR_ERR(dentry);
655 goto out;
656 }
657
658 down_read(&REISERFS_I(inode)->i_xattr_sem);
659
660 isize = i_size_read(d_inode(dentry));
661
662
663 if (buffer == NULL) {
664 err = isize - sizeof(struct reiserfs_xattr_header);
665 goto out_unlock;
666 }
667
668 if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
669 err = -ERANGE;
670 goto out_unlock;
671 }
672
673 while (file_pos < isize) {
674 size_t chunk;
675 char *data;
676 size_t skip = 0;
677
678 if (isize - file_pos > PAGE_CACHE_SIZE)
679 chunk = PAGE_CACHE_SIZE;
680 else
681 chunk = isize - file_pos;
682
683 page = reiserfs_get_page(d_inode(dentry), file_pos);
684 if (IS_ERR(page)) {
685 err = PTR_ERR(page);
686 goto out_unlock;
687 }
688
689 lock_page(page);
690 data = page_address(page);
691 if (file_pos == 0) {
692 struct reiserfs_xattr_header *rxh =
693 (struct reiserfs_xattr_header *)data;
694 skip = file_pos = sizeof(struct reiserfs_xattr_header);
695 chunk -= skip;
696
697 if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
698 unlock_page(page);
699 reiserfs_put_page(page);
700 reiserfs_warning(inode->i_sb, "jdm-20001",
701 "Invalid magic for xattr (%s) "
702 "associated with %k", name,
703 INODE_PKEY(inode));
704 err = -EIO;
705 goto out_unlock;
706 }
707 hash = le32_to_cpu(rxh->h_hash);
708 }
709 memcpy(buffer + buffer_pos, data + skip, chunk);
710 unlock_page(page);
711 reiserfs_put_page(page);
712 file_pos += chunk;
713 buffer_pos += chunk;
714 skip = 0;
715 }
716 err = isize - sizeof(struct reiserfs_xattr_header);
717
718 if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
719 hash) {
720 reiserfs_warning(inode->i_sb, "jdm-20002",
721 "Invalid hash for xattr (%s) associated "
722 "with %k", name, INODE_PKEY(inode));
723 err = -EIO;
724 }
725
726out_unlock:
727 up_read(&REISERFS_I(inode)->i_xattr_sem);
728 dput(dentry);
729
730out:
731 return err;
732}
733
734
735
736
737
738
739
740
741
742
743#define for_each_xattr_handler(handlers, handler) \
744 for ((handler) = *(handlers)++; \
745 (handler) != NULL; \
746 (handler) = *(handlers)++)
747
748
749static inline const struct xattr_handler *
750find_xattr_handler_prefix(const struct xattr_handler **handlers,
751 const char *name)
752{
753 const struct xattr_handler *xah;
754
755 if (!handlers)
756 return NULL;
757
758 for_each_xattr_handler(handlers, xah) {
759 if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
760 break;
761 }
762
763 return xah;
764}
765
766
767
768
769
770ssize_t
771reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
772 size_t size)
773{
774 const struct xattr_handler *handler;
775
776 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
777
778 if (!handler || get_inode_sd_version(d_inode(dentry)) == STAT_DATA_V1)
779 return -EOPNOTSUPP;
780
781 return handler->get(dentry, name, buffer, size, handler->flags);
782}
783
784
785
786
787
788
789int
790reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
791 size_t size, int flags)
792{
793 const struct xattr_handler *handler;
794
795 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
796
797 if (!handler || get_inode_sd_version(d_inode(dentry)) == STAT_DATA_V1)
798 return -EOPNOTSUPP;
799
800 return handler->set(dentry, name, value, size, flags, handler->flags);
801}
802
803
804
805
806
807
808int reiserfs_removexattr(struct dentry *dentry, const char *name)
809{
810 const struct xattr_handler *handler;
811
812 handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
813
814 if (!handler || get_inode_sd_version(d_inode(dentry)) == STAT_DATA_V1)
815 return -EOPNOTSUPP;
816
817 return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
818}
819
820struct listxattr_buf {
821 struct dir_context ctx;
822 size_t size;
823 size_t pos;
824 char *buf;
825 struct dentry *dentry;
826};
827
828static int listxattr_filler(struct dir_context *ctx, const char *name,
829 int namelen, loff_t offset, u64 ino,
830 unsigned int d_type)
831{
832 struct listxattr_buf *b =
833 container_of(ctx, struct listxattr_buf, ctx);
834 size_t size;
835
836 if (name[0] != '.' ||
837 (namelen != 1 && (name[1] != '.' || namelen != 2))) {
838 const struct xattr_handler *handler;
839
840 handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
841 name);
842 if (!handler)
843 return 0;
844 if (b->buf) {
845 size = handler->list(b->dentry, b->buf + b->pos,
846 b->size, name, namelen,
847 handler->flags);
848 if (size > b->size)
849 return -ERANGE;
850 } else {
851 size = handler->list(b->dentry, NULL, 0, name,
852 namelen, handler->flags);
853 }
854
855 b->pos += size;
856 }
857 return 0;
858}
859
860
861
862
863
864
865
866
867ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
868{
869 struct dentry *dir;
870 int err = 0;
871 struct listxattr_buf buf = {
872 .ctx.actor = listxattr_filler,
873 .dentry = dentry,
874 .buf = buffer,
875 .size = buffer ? size : 0,
876 };
877
878 if (d_really_is_negative(dentry))
879 return -EINVAL;
880
881 if (!dentry->d_sb->s_xattr ||
882 get_inode_sd_version(d_inode(dentry)) == STAT_DATA_V1)
883 return -EOPNOTSUPP;
884
885 dir = open_xa_dir(d_inode(dentry), XATTR_REPLACE);
886 if (IS_ERR(dir)) {
887 err = PTR_ERR(dir);
888 if (err == -ENODATA)
889 err = 0;
890 goto out;
891 }
892
893 mutex_lock_nested(&d_inode(dir)->i_mutex, I_MUTEX_XATTR);
894 err = reiserfs_readdir_inode(d_inode(dir), &buf.ctx);
895 mutex_unlock(&d_inode(dir)->i_mutex);
896
897 if (!err)
898 err = buf.pos;
899
900 dput(dir);
901out:
902 return err;
903}
904
905static int create_privroot(struct dentry *dentry)
906{
907 int err;
908 struct inode *inode = d_inode(dentry->d_parent);
909
910 WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
911
912 err = xattr_mkdir(inode, dentry, 0700);
913 if (err || d_really_is_negative(dentry)) {
914 reiserfs_warning(dentry->d_sb, "jdm-20006",
915 "xattrs/ACLs enabled and couldn't "
916 "find/create .reiserfs_priv. "
917 "Failing mount.");
918 return -EOPNOTSUPP;
919 }
920
921 d_inode(dentry)->i_flags |= S_PRIVATE;
922 reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
923 "storage.\n", PRIVROOT_NAME);
924
925 return 0;
926}
927
928#else
929int __init reiserfs_xattr_register_handlers(void) { return 0; }
930void reiserfs_xattr_unregister_handlers(void) {}
931static int create_privroot(struct dentry *dentry) { return 0; }
932#endif
933
934
935static const struct xattr_handler *reiserfs_xattr_handlers[] = {
936#ifdef CONFIG_REISERFS_FS_XATTR
937 &reiserfs_xattr_user_handler,
938 &reiserfs_xattr_trusted_handler,
939#endif
940#ifdef CONFIG_REISERFS_FS_SECURITY
941 &reiserfs_xattr_security_handler,
942#endif
943#ifdef CONFIG_REISERFS_FS_POSIX_ACL
944 &posix_acl_access_xattr_handler,
945 &posix_acl_default_xattr_handler,
946#endif
947 NULL
948};
949
950static int xattr_mount_check(struct super_block *s)
951{
952
953
954
955
956 if (old_format_only(s)) {
957 if (reiserfs_xattrs_optional(s)) {
958
959
960
961
962 reiserfs_warning(s, "jdm-2005",
963 "xattrs/ACLs not supported "
964 "on pre-v3.6 format filesystems. "
965 "Failing mount.");
966 return -EOPNOTSUPP;
967 }
968 }
969
970 return 0;
971}
972
973int reiserfs_permission(struct inode *inode, int mask)
974{
975
976
977
978
979 if (IS_PRIVATE(inode))
980 return 0;
981
982 return generic_permission(inode, mask);
983}
984
985static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
986{
987 return -EPERM;
988}
989
990static const struct dentry_operations xattr_lookup_poison_ops = {
991 .d_revalidate = xattr_hide_revalidate,
992};
993
994int reiserfs_lookup_privroot(struct super_block *s)
995{
996 struct dentry *dentry;
997 int err = 0;
998
999
1000 mutex_lock(&d_inode(s->s_root)->i_mutex);
1001 dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
1002 strlen(PRIVROOT_NAME));
1003 if (!IS_ERR(dentry)) {
1004 REISERFS_SB(s)->priv_root = dentry;
1005 d_set_d_op(dentry, &xattr_lookup_poison_ops);
1006 if (d_really_is_positive(dentry))
1007 d_inode(dentry)->i_flags |= S_PRIVATE;
1008 } else
1009 err = PTR_ERR(dentry);
1010 mutex_unlock(&d_inode(s->s_root)->i_mutex);
1011
1012 return err;
1013}
1014
1015
1016
1017
1018
1019
1020int reiserfs_xattr_init(struct super_block *s, int mount_flags)
1021{
1022 int err = 0;
1023 struct dentry *privroot = REISERFS_SB(s)->priv_root;
1024
1025 err = xattr_mount_check(s);
1026 if (err)
1027 goto error;
1028
1029 if (d_really_is_negative(privroot) && !(mount_flags & MS_RDONLY)) {
1030 mutex_lock(&d_inode(s->s_root)->i_mutex);
1031 err = create_privroot(REISERFS_SB(s)->priv_root);
1032 mutex_unlock(&d_inode(s->s_root)->i_mutex);
1033 }
1034
1035 if (d_really_is_positive(privroot)) {
1036 s->s_xattr = reiserfs_xattr_handlers;
1037 mutex_lock(&d_inode(privroot)->i_mutex);
1038 if (!REISERFS_SB(s)->xattr_root) {
1039 struct dentry *dentry;
1040
1041 dentry = lookup_one_len(XAROOT_NAME, privroot,
1042 strlen(XAROOT_NAME));
1043 if (!IS_ERR(dentry))
1044 REISERFS_SB(s)->xattr_root = dentry;
1045 else
1046 err = PTR_ERR(dentry);
1047 }
1048 mutex_unlock(&d_inode(privroot)->i_mutex);
1049 }
1050
1051error:
1052 if (err) {
1053 clear_bit(REISERFS_XATTRS_USER, &REISERFS_SB(s)->s_mount_opt);
1054 clear_bit(REISERFS_POSIXACL, &REISERFS_SB(s)->s_mount_opt);
1055 }
1056
1057
1058 if (reiserfs_posixacl(s))
1059 s->s_flags |= MS_POSIXACL;
1060 else
1061 s->s_flags &= ~MS_POSIXACL;
1062
1063 return err;
1064}
1065