forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 17
/
xattr.c
1125 lines (986 loc) · 27.3 KB
/
xattr.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Copyright (C) International Business Machines Corp., 2000-2004
* Copyright (C) Christoph Hellwig, 2002
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
#include <linux/slab.h>
#include <linux/quotaops.h>
#include <linux/security.h>
#include "jfs_incore.h"
#include "jfs_superblock.h"
#include "jfs_dmap.h"
#include "jfs_debug.h"
#include "jfs_dinode.h"
#include "jfs_extent.h"
#include "jfs_metapage.h"
#include "jfs_xattr.h"
#include "jfs_acl.h"
/*
* jfs_xattr.c: extended attribute service
*
* Overall design --
*
* Format:
*
* Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit
* value) and a variable (0 or more) number of extended attribute
* entries. Each extended attribute entry (jfs_ea) is a <name,value> double
* where <name> is constructed from a null-terminated ascii string
* (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data
* (1 ... 65535 bytes). The in-memory format is
*
* 0 1 2 4 4 + namelen + 1
* +-------+--------+--------+----------------+-------------------+
* | Flags | Name | Value | Name String \0 | Data . . . . |
* | | Length | Length | | |
* +-------+--------+--------+----------------+-------------------+
*
* A jfs_ea_list then is structured as
*
* 0 4 4 + EA_SIZE(ea1)
* +------------+-------------------+--------------------+-----
* | Overall EA | First FEA Element | Second FEA Element | .....
* | List Size | | |
* +------------+-------------------+--------------------+-----
*
* On-disk:
*
* FEALISTs are stored on disk using blocks allocated by dbAlloc() and
* written directly. An EA list may be in-lined in the inode if there is
* sufficient room available.
*/
struct ea_buffer {
int flag; /* Indicates what storage xattr points to */
int max_size; /* largest xattr that fits in current buffer */
dxd_t new_ea; /* dxd to replace ea when modifying xattr */
struct metapage *mp; /* metapage containing ea list */
struct jfs_ea_list *xattr; /* buffer containing ea list */
};
/*
* ea_buffer.flag values
*/
#define EA_INLINE 0x0001
#define EA_EXTENT 0x0002
#define EA_NEW 0x0004
#define EA_MALLOC 0x0008
static int is_known_namespace(const char *name)
{
if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
return false;
return true;
}
/*
* These three routines are used to recognize on-disk extended attributes
* that are in a recognized namespace. If the attribute is not recognized,
* "os2." is prepended to the name
*/
static int is_os2_xattr(struct jfs_ea *ea)
{
return !is_known_namespace(ea->name);
}
static inline int name_size(struct jfs_ea *ea)
{
if (is_os2_xattr(ea))
return ea->namelen + XATTR_OS2_PREFIX_LEN;
else
return ea->namelen;
}
static inline int copy_name(char *buffer, struct jfs_ea *ea)
{
int len = ea->namelen;
if (is_os2_xattr(ea)) {
memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN);
buffer += XATTR_OS2_PREFIX_LEN;
len += XATTR_OS2_PREFIX_LEN;
}
memcpy(buffer, ea->name, ea->namelen);
buffer[ea->namelen] = 0;
return len;
}
/* Forward references */
static void ea_release(struct inode *inode, struct ea_buffer *ea_buf);
/*
* NAME: ea_write_inline
*
* FUNCTION: Attempt to write an EA inline if area is available
*
* PRE CONDITIONS:
* Already verified that the specified EA is small enough to fit inline
*
* PARAMETERS:
* ip - Inode pointer
* ealist - EA list pointer
* size - size of ealist in bytes
* ea - dxd_t structure to be filled in with necessary EA information
* if we successfully copy the EA inline
*
* NOTES:
* Checks if the inode's inline area is available. If so, copies EA inline
* and sets <ea> fields appropriately. Otherwise, returns failure, EA will
* have to be put into an extent.
*
* RETURNS: 0 for successful copy to inline area; -1 if area not available
*/
static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist,
int size, dxd_t * ea)
{
struct jfs_inode_info *ji = JFS_IP(ip);
/*
* Make sure we have an EA -- the NULL EA list is valid, but you
* can't copy it!
*/
if (ealist && size > sizeof (struct jfs_ea_list)) {
assert(size <= sizeof (ji->i_inline_ea));
/*
* See if the space is available or if it is already being
* used for an inline EA.
*/
if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE))
return -EPERM;
DXDsize(ea, size);
DXDlength(ea, 0);
DXDaddress(ea, 0);
memcpy(ji->i_inline_ea, ealist, size);
ea->flag = DXD_INLINE;
ji->mode2 &= ~INLINEEA;
} else {
ea->flag = 0;
DXDsize(ea, 0);
DXDlength(ea, 0);
DXDaddress(ea, 0);
/* Free up INLINE area */
if (ji->ea.flag & DXD_INLINE)
ji->mode2 |= INLINEEA;
}
return 0;
}
/*
* NAME: ea_write
*
* FUNCTION: Write an EA for an inode
*
* PRE CONDITIONS: EA has been verified
*
* PARAMETERS:
* ip - Inode pointer
* ealist - EA list pointer
* size - size of ealist in bytes
* ea - dxd_t structure to be filled in appropriately with where the
* EA was copied
*
* NOTES: Will write EA inline if able to, otherwise allocates blocks for an
* extent and synchronously writes it to those blocks.
*
* RETURNS: 0 for success; Anything else indicates failure
*/
static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size,
dxd_t * ea)
{
struct super_block *sb = ip->i_sb;
struct jfs_inode_info *ji = JFS_IP(ip);
struct jfs_sb_info *sbi = JFS_SBI(sb);
int nblocks;
s64 blkno;
int rc = 0, i;
char *cp;
s32 nbytes, nb;
s32 bytes_to_write;
struct metapage *mp;
/*
* Quick check to see if this is an in-linable EA. Short EAs
* and empty EAs are all in-linable, provided the space exists.
*/
if (!ealist || size <= sizeof (ji->i_inline_ea)) {
if (!ea_write_inline(ip, ealist, size, ea))
return 0;
}
/* figure out how many blocks we need */
nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
/* Allocate new blocks to quota. */
rc = dquot_alloc_block(ip, nblocks);
if (rc)
return rc;
rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
if (rc) {
/*Rollback quota allocation. */
dquot_free_block(ip, nblocks);
return rc;
}
/*
* Now have nblocks worth of storage to stuff into the FEALIST.
* loop over the FEALIST copying data into the buffer one page at
* a time.
*/
cp = (char *) ealist;
nbytes = size;
for (i = 0; i < nblocks; i += sbi->nbperpage) {
/*
* Determine how many bytes for this request, and round up to
* the nearest aggregate block size
*/
nb = min(PSIZE, nbytes);
bytes_to_write =
((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
<< sb->s_blocksize_bits;
if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) {
rc = -EIO;
goto failed;
}
memcpy(mp->data, cp, nb);
/*
* We really need a way to propagate errors for
* forced writes like this one. --hch
*
* (__write_metapage => release_metapage => flush_metapage)
*/
#ifdef _JFS_FIXME
if ((rc = flush_metapage(mp))) {
/*
* the write failed -- this means that the buffer
* is still assigned and the blocks are not being
* used. this seems like the best error recovery
* we can get ...
*/
goto failed;
}
#else
flush_metapage(mp);
#endif
cp += PSIZE;
nbytes -= nb;
}
ea->flag = DXD_EXTENT;
DXDsize(ea, le32_to_cpu(ealist->size));
DXDlength(ea, nblocks);
DXDaddress(ea, blkno);
/* Free up INLINE area */
if (ji->ea.flag & DXD_INLINE)
ji->mode2 |= INLINEEA;
return 0;
failed:
/* Rollback quota allocation. */
dquot_free_block(ip, nblocks);
dbFree(ip, blkno, nblocks);
return rc;
}
/*
* NAME: ea_read_inline
*
* FUNCTION: Read an inlined EA into user's buffer
*
* PARAMETERS:
* ip - Inode pointer
* ealist - Pointer to buffer to fill in with EA
*
* RETURNS: 0
*/
static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist)
{
struct jfs_inode_info *ji = JFS_IP(ip);
int ea_size = sizeDXD(&ji->ea);
if (ea_size == 0) {
ealist->size = 0;
return 0;
}
/* Sanity Check */
if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea)))
return -EIO;
if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size)
!= ea_size)
return -EIO;
memcpy(ealist, ji->i_inline_ea, ea_size);
return 0;
}
/*
* NAME: ea_read
*
* FUNCTION: copy EA data into user's buffer
*
* PARAMETERS:
* ip - Inode pointer
* ealist - Pointer to buffer to fill in with EA
*
* NOTES: If EA is inline calls ea_read_inline() to copy EA.
*
* RETURNS: 0 for success; other indicates failure
*/
static int ea_read(struct inode *ip, struct jfs_ea_list *ealist)
{
struct super_block *sb = ip->i_sb;
struct jfs_inode_info *ji = JFS_IP(ip);
struct jfs_sb_info *sbi = JFS_SBI(sb);
int nblocks;
s64 blkno;
char *cp = (char *) ealist;
int i;
int nbytes, nb;
s32 bytes_to_read;
struct metapage *mp;
/* quick check for in-line EA */
if (ji->ea.flag & DXD_INLINE)
return ea_read_inline(ip, ealist);
nbytes = sizeDXD(&ji->ea);
if (!nbytes) {
jfs_error(sb, "ea_read: nbytes is 0");
return -EIO;
}
/*
* Figure out how many blocks were allocated when this EA list was
* originally written to disk.
*/
nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage;
blkno = addressDXD(&ji->ea) << sbi->l2nbperpage;
/*
* I have found the disk blocks which were originally used to store
* the FEALIST. now i loop over each contiguous block copying the
* data into the buffer.
*/
for (i = 0; i < nblocks; i += sbi->nbperpage) {
/*
* Determine how many bytes for this request, and round up to
* the nearest aggregate block size
*/
nb = min(PSIZE, nbytes);
bytes_to_read =
((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
<< sb->s_blocksize_bits;
if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1)))
return -EIO;
memcpy(cp, mp->data, nb);
release_metapage(mp);
cp += PSIZE;
nbytes -= nb;
}
return 0;
}
/*
* NAME: ea_get
*
* FUNCTION: Returns buffer containing existing extended attributes.
* The size of the buffer will be the larger of the existing
* attributes size, or min_size.
*
* The buffer, which may be inlined in the inode or in the
* page cache must be release by calling ea_release or ea_put
*
* PARAMETERS:
* inode - Inode pointer
* ea_buf - Structure to be populated with ealist and its metadata
* min_size- minimum size of buffer to be returned
*
* RETURNS: 0 for success; Other indicates failure
*/
static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
{
struct jfs_inode_info *ji = JFS_IP(inode);
struct super_block *sb = inode->i_sb;
int size;
int ea_size = sizeDXD(&ji->ea);
int blocks_needed, current_blocks;
s64 blkno;
int rc;
int quota_allocation = 0;
/* When fsck.jfs clears a bad ea, it doesn't clear the size */
if (ji->ea.flag == 0)
ea_size = 0;
if (ea_size == 0) {
if (min_size == 0) {
ea_buf->flag = 0;
ea_buf->max_size = 0;
ea_buf->xattr = NULL;
return 0;
}
if ((min_size <= sizeof (ji->i_inline_ea)) &&
(ji->mode2 & INLINEEA)) {
ea_buf->flag = EA_INLINE | EA_NEW;
ea_buf->max_size = sizeof (ji->i_inline_ea);
ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
DXDlength(&ea_buf->new_ea, 0);
DXDaddress(&ea_buf->new_ea, 0);
ea_buf->new_ea.flag = DXD_INLINE;
DXDsize(&ea_buf->new_ea, min_size);
return 0;
}
current_blocks = 0;
} else if (ji->ea.flag & DXD_INLINE) {
if (min_size <= sizeof (ji->i_inline_ea)) {
ea_buf->flag = EA_INLINE;
ea_buf->max_size = sizeof (ji->i_inline_ea);
ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
goto size_check;
}
current_blocks = 0;
} else {
if (!(ji->ea.flag & DXD_EXTENT)) {
jfs_error(sb, "ea_get: invalid ea.flag)");
return -EIO;
}
current_blocks = (ea_size + sb->s_blocksize - 1) >>
sb->s_blocksize_bits;
}
size = max(min_size, ea_size);
if (size > PSIZE) {
/*
* To keep the rest of the code simple. Allocate a
* contiguous buffer to work with
*/
ea_buf->xattr = kmalloc(size, GFP_KERNEL);
if (ea_buf->xattr == NULL)
return -ENOMEM;
ea_buf->flag = EA_MALLOC;
ea_buf->max_size = (size + sb->s_blocksize - 1) &
~(sb->s_blocksize - 1);
if (ea_size == 0)
return 0;
if ((rc = ea_read(inode, ea_buf->xattr))) {
kfree(ea_buf->xattr);
ea_buf->xattr = NULL;
return rc;
}
goto size_check;
}
blocks_needed = (min_size + sb->s_blocksize - 1) >>
sb->s_blocksize_bits;
if (blocks_needed > current_blocks) {
/* Allocate new blocks to quota. */
rc = dquot_alloc_block(inode, blocks_needed);
if (rc)
return -EDQUOT;
quota_allocation = blocks_needed;
rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed,
&blkno);
if (rc)
goto clean_up;
DXDlength(&ea_buf->new_ea, blocks_needed);
DXDaddress(&ea_buf->new_ea, blkno);
ea_buf->new_ea.flag = DXD_EXTENT;
DXDsize(&ea_buf->new_ea, min_size);
ea_buf->flag = EA_EXTENT | EA_NEW;
ea_buf->mp = get_metapage(inode, blkno,
blocks_needed << sb->s_blocksize_bits,
1);
if (ea_buf->mp == NULL) {
dbFree(inode, blkno, (s64) blocks_needed);
rc = -EIO;
goto clean_up;
}
ea_buf->xattr = ea_buf->mp->data;
ea_buf->max_size = (min_size + sb->s_blocksize - 1) &
~(sb->s_blocksize - 1);
if (ea_size == 0)
return 0;
if ((rc = ea_read(inode, ea_buf->xattr))) {
discard_metapage(ea_buf->mp);
dbFree(inode, blkno, (s64) blocks_needed);
goto clean_up;
}
goto size_check;
}
ea_buf->flag = EA_EXTENT;
ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea),
lengthDXD(&ji->ea) << sb->s_blocksize_bits,
1);
if (ea_buf->mp == NULL) {
rc = -EIO;
goto clean_up;
}
ea_buf->xattr = ea_buf->mp->data;
ea_buf->max_size = (ea_size + sb->s_blocksize - 1) &
~(sb->s_blocksize - 1);
size_check:
if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
printk(KERN_ERR "ea_get: invalid extended attribute\n");
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
ea_buf->xattr, ea_size, 1);
ea_release(inode, ea_buf);
rc = -EIO;
goto clean_up;
}
return ea_size;
clean_up:
/* Rollback quota allocation */
if (quota_allocation)
dquot_free_block(inode, quota_allocation);
return (rc);
}
static void ea_release(struct inode *inode, struct ea_buffer *ea_buf)
{
if (ea_buf->flag & EA_MALLOC)
kfree(ea_buf->xattr);
else if (ea_buf->flag & EA_EXTENT) {
assert(ea_buf->mp);
release_metapage(ea_buf->mp);
if (ea_buf->flag & EA_NEW)
dbFree(inode, addressDXD(&ea_buf->new_ea),
lengthDXD(&ea_buf->new_ea));
}
}
static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
int new_size)
{
struct jfs_inode_info *ji = JFS_IP(inode);
unsigned long old_blocks, new_blocks;
int rc = 0;
if (new_size == 0) {
ea_release(inode, ea_buf);
ea_buf = NULL;
} else if (ea_buf->flag & EA_INLINE) {
assert(new_size <= sizeof (ji->i_inline_ea));
ji->mode2 &= ~INLINEEA;
ea_buf->new_ea.flag = DXD_INLINE;
DXDsize(&ea_buf->new_ea, new_size);
DXDaddress(&ea_buf->new_ea, 0);
DXDlength(&ea_buf->new_ea, 0);
} else if (ea_buf->flag & EA_MALLOC) {
rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
kfree(ea_buf->xattr);
} else if (ea_buf->flag & EA_NEW) {
/* We have already allocated a new dxd */
flush_metapage(ea_buf->mp);
} else {
/* ->xattr must point to original ea's metapage */
rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
discard_metapage(ea_buf->mp);
}
if (rc)
return rc;
old_blocks = new_blocks = 0;
if (ji->ea.flag & DXD_EXTENT) {
invalidate_dxd_metapages(inode, ji->ea);
old_blocks = lengthDXD(&ji->ea);
}
if (ea_buf) {
txEA(tid, inode, &ji->ea, &ea_buf->new_ea);
if (ea_buf->new_ea.flag & DXD_EXTENT) {
new_blocks = lengthDXD(&ea_buf->new_ea);
if (ji->ea.flag & DXD_INLINE)
ji->mode2 |= INLINEEA;
}
ji->ea = ea_buf->new_ea;
} else {
txEA(tid, inode, &ji->ea, NULL);
if (ji->ea.flag & DXD_INLINE)
ji->mode2 |= INLINEEA;
ji->ea.flag = 0;
ji->ea.size = 0;
}
/* If old blocks exist, they must be removed from quota allocation. */
if (old_blocks)
dquot_free_block(inode, old_blocks);
inode->i_ctime = CURRENT_TIME;
return 0;
}
/*
* can_set_system_xattr
*
* This code is specific to the system.* namespace. It contains policy
* which doesn't belong in the main xattr codepath.
*/
static int can_set_system_xattr(struct inode *inode, const char *name,
const void *value, size_t value_len)
{
#ifdef CONFIG_JFS_POSIX_ACL
struct posix_acl *acl;
int rc;
if (!inode_owner_or_capable(inode))
return -EPERM;
/*
* POSIX_ACL_XATTR_ACCESS is tied to i_mode
*/
if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0) {
acl = posix_acl_from_xattr(value, value_len);
if (IS_ERR(acl)) {
rc = PTR_ERR(acl);
printk(KERN_ERR "posix_acl_from_xattr returned %d\n",
rc);
return rc;
}
if (acl) {
rc = posix_acl_equiv_mode(acl, &inode->i_mode);
posix_acl_release(acl);
if (rc < 0) {
printk(KERN_ERR
"posix_acl_equiv_mode returned %d\n",
rc);
return rc;
}
mark_inode_dirty(inode);
}
/*
* We're changing the ACL. Get rid of the cached one
*/
forget_cached_acl(inode, ACL_TYPE_ACCESS);
return 0;
} else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0) {
acl = posix_acl_from_xattr(value, value_len);
if (IS_ERR(acl)) {
rc = PTR_ERR(acl);
printk(KERN_ERR "posix_acl_from_xattr returned %d\n",
rc);
return rc;
}
posix_acl_release(acl);
/*
* We're changing the default ACL. Get rid of the cached one
*/
forget_cached_acl(inode, ACL_TYPE_DEFAULT);
return 0;
}
#endif /* CONFIG_JFS_POSIX_ACL */
return -EOPNOTSUPP;
}
/*
* Most of the permission checking is done by xattr_permission in the vfs.
* The local file system is responsible for handling the system.* namespace.
* We also need to verify that this is a namespace that we recognize.
*/
static int can_set_xattr(struct inode *inode, const char *name,
const void *value, size_t value_len)
{
if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
return can_set_system_xattr(inode, name, value, value_len);
if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) {
/*
* This makes sure that we aren't trying to set an
* attribute in a different namespace by prefixing it
* with "os2."
*/
if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN))
return -EOPNOTSUPP;
return 0;
}
/*
* Don't allow setting an attribute in an unknown namespace.
*/
if (strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) &&
strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
return -EOPNOTSUPP;
return 0;
}
int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name,
const void *value, size_t value_len, int flags)
{
struct jfs_ea_list *ealist;
struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL;
struct ea_buffer ea_buf;
int old_ea_size = 0;
int xattr_size;
int new_size;
int namelen = strlen(name);
char *os2name = NULL;
int found = 0;
int rc;
int length;
if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1,
GFP_KERNEL);
if (!os2name)
return -ENOMEM;
strcpy(os2name, name + XATTR_OS2_PREFIX_LEN);
name = os2name;
namelen -= XATTR_OS2_PREFIX_LEN;
}
down_write(&JFS_IP(inode)->xattr_sem);
xattr_size = ea_get(inode, &ea_buf, 0);
if (xattr_size < 0) {
rc = xattr_size;
goto out;
}
again:
ealist = (struct jfs_ea_list *) ea_buf.xattr;
new_size = sizeof (struct jfs_ea_list);
if (xattr_size) {
for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist);
ea = NEXT_EA(ea)) {
if ((namelen == ea->namelen) &&
(memcmp(name, ea->name, namelen) == 0)) {
found = 1;
if (flags & XATTR_CREATE) {
rc = -EEXIST;
goto release;
}
old_ea = ea;
old_ea_size = EA_SIZE(ea);
next_ea = NEXT_EA(ea);
} else
new_size += EA_SIZE(ea);
}
}
if (!found) {
if (flags & XATTR_REPLACE) {
rc = -ENODATA;
goto release;
}
if (value == NULL) {
rc = 0;
goto release;
}
}
if (value)
new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len;
if (new_size > ea_buf.max_size) {
/*
* We need to allocate more space for merged ea list.
* We should only have loop to again: once.
*/
ea_release(inode, &ea_buf);
xattr_size = ea_get(inode, &ea_buf, new_size);
if (xattr_size < 0) {
rc = xattr_size;
goto out;
}
goto again;
}
/* Remove old ea of the same name */
if (found) {
/* number of bytes following target EA */
length = (char *) END_EALIST(ealist) - (char *) next_ea;
if (length > 0)
memmove(old_ea, next_ea, length);
xattr_size -= old_ea_size;
}
/* Add new entry to the end */
if (value) {
if (xattr_size == 0)
/* Completely new ea list */
xattr_size = sizeof (struct jfs_ea_list);
ea = (struct jfs_ea *) ((char *) ealist + xattr_size);
ea->flag = 0;
ea->namelen = namelen;
ea->valuelen = (cpu_to_le16(value_len));
memcpy(ea->name, name, namelen);
ea->name[namelen] = 0;
if (value_len)
memcpy(&ea->name[namelen + 1], value, value_len);
xattr_size += EA_SIZE(ea);
}
/* DEBUG - If we did this right, these number match */
if (xattr_size != new_size) {
printk(KERN_ERR
"jfs_xsetattr: xattr_size = %d, new_size = %d\n",
xattr_size, new_size);
rc = -EINVAL;
goto release;
}
/*
* If we're left with an empty list, there's no ea
*/
if (new_size == sizeof (struct jfs_ea_list))
new_size = 0;
ealist->size = cpu_to_le32(new_size);
rc = ea_put(tid, inode, &ea_buf, new_size);
goto out;
release:
ea_release(inode, &ea_buf);
out:
up_write(&JFS_IP(inode)->xattr_sem);
kfree(os2name);
return rc;
}
int jfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t value_len, int flags)
{
struct inode *inode = dentry->d_inode;
struct jfs_inode_info *ji = JFS_IP(inode);
int rc;
tid_t tid;
if ((rc = can_set_xattr(inode, name, value, value_len)))
return rc;
if (value == NULL) { /* empty EA, do not remove */
value = "";
value_len = 0;
}
tid = txBegin(inode->i_sb, 0);
mutex_lock(&ji->commit_mutex);
rc = __jfs_setxattr(tid, dentry->d_inode, name, value, value_len,
flags);
if (!rc)
rc = txCommit(tid, 1, &inode, 0);
txEnd(tid);
mutex_unlock(&ji->commit_mutex);
return rc;
}
ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data,
size_t buf_size)
{
struct jfs_ea_list *ealist;
struct jfs_ea *ea;
struct ea_buffer ea_buf;
int xattr_size;
ssize_t size;
int namelen = strlen(name);
char *value;
down_read(&JFS_IP(inode)->xattr_sem);
xattr_size = ea_get(inode, &ea_buf, 0);
if (xattr_size < 0) {
size = xattr_size;
goto out;
}
if (xattr_size == 0)
goto not_found;
ealist = (struct jfs_ea_list *) ea_buf.xattr;
/* Find the named attribute */
for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea))
if ((namelen == ea->namelen) &&
memcmp(name, ea->name, namelen) == 0) {
/* Found it */
size = le16_to_cpu(ea->valuelen);
if (!data)
goto release;
else if (size > buf_size) {
size = -ERANGE;
goto release;
}
value = ((char *) &ea->name) + ea->namelen + 1;
memcpy(data, value, size);
goto release;
}
not_found:
size = -ENODATA;
release:
ea_release(inode, &ea_buf);
out:
up_read(&JFS_IP(inode)->xattr_sem);
return size;
}
ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data,
size_t buf_size)
{
int err;
if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
/*
* skip past "os2." prefix
*/
name += XATTR_OS2_PREFIX_LEN;
/*
* Don't allow retrieving properly prefixed attributes
* by prepending them with "os2."
*/
if (is_known_namespace(name))
return -EOPNOTSUPP;
}