Loading...
1/*
2 * Copyright (C) International Business Machines Corp., 2000-2004
3 * Copyright (C) Christoph Hellwig, 2002
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20#include <linux/capability.h>
21#include <linux/fs.h>
22#include <linux/xattr.h>
23#include <linux/posix_acl_xattr.h>
24#include <linux/slab.h>
25#include <linux/quotaops.h>
26#include <linux/security.h>
27#include "jfs_incore.h"
28#include "jfs_superblock.h"
29#include "jfs_dmap.h"
30#include "jfs_debug.h"
31#include "jfs_dinode.h"
32#include "jfs_extent.h"
33#include "jfs_metapage.h"
34#include "jfs_xattr.h"
35#include "jfs_acl.h"
36
37/*
38 * jfs_xattr.c: extended attribute service
39 *
40 * Overall design --
41 *
42 * Format:
43 *
44 * Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit
45 * value) and a variable (0 or more) number of extended attribute
46 * entries. Each extended attribute entry (jfs_ea) is a <name,value> double
47 * where <name> is constructed from a null-terminated ascii string
48 * (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data
49 * (1 ... 65535 bytes). The in-memory format is
50 *
51 * 0 1 2 4 4 + namelen + 1
52 * +-------+--------+--------+----------------+-------------------+
53 * | Flags | Name | Value | Name String \0 | Data . . . . |
54 * | | Length | Length | | |
55 * +-------+--------+--------+----------------+-------------------+
56 *
57 * A jfs_ea_list then is structured as
58 *
59 * 0 4 4 + EA_SIZE(ea1)
60 * +------------+-------------------+--------------------+-----
61 * | Overall EA | First FEA Element | Second FEA Element | .....
62 * | List Size | | |
63 * +------------+-------------------+--------------------+-----
64 *
65 * On-disk:
66 *
67 * FEALISTs are stored on disk using blocks allocated by dbAlloc() and
68 * written directly. An EA list may be in-lined in the inode if there is
69 * sufficient room available.
70 */
71
72struct ea_buffer {
73 int flag; /* Indicates what storage xattr points to */
74 int max_size; /* largest xattr that fits in current buffer */
75 dxd_t new_ea; /* dxd to replace ea when modifying xattr */
76 struct metapage *mp; /* metapage containing ea list */
77 struct jfs_ea_list *xattr; /* buffer containing ea list */
78};
79
80/*
81 * ea_buffer.flag values
82 */
83#define EA_INLINE 0x0001
84#define EA_EXTENT 0x0002
85#define EA_NEW 0x0004
86#define EA_MALLOC 0x0008
87
88
89static int is_known_namespace(const char *name)
90{
91 if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
92 strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
93 strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
94 strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
95 return false;
96
97 return true;
98}
99
100/*
101 * These three routines are used to recognize on-disk extended attributes
102 * that are in a recognized namespace. If the attribute is not recognized,
103 * "os2." is prepended to the name
104 */
105static int is_os2_xattr(struct jfs_ea *ea)
106{
107 return !is_known_namespace(ea->name);
108}
109
110static inline int name_size(struct jfs_ea *ea)
111{
112 if (is_os2_xattr(ea))
113 return ea->namelen + XATTR_OS2_PREFIX_LEN;
114 else
115 return ea->namelen;
116}
117
118static inline int copy_name(char *buffer, struct jfs_ea *ea)
119{
120 int len = ea->namelen;
121
122 if (is_os2_xattr(ea)) {
123 memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN);
124 buffer += XATTR_OS2_PREFIX_LEN;
125 len += XATTR_OS2_PREFIX_LEN;
126 }
127 memcpy(buffer, ea->name, ea->namelen);
128 buffer[ea->namelen] = 0;
129
130 return len;
131}
132
133/* Forward references */
134static void ea_release(struct inode *inode, struct ea_buffer *ea_buf);
135
136/*
137 * NAME: ea_write_inline
138 *
139 * FUNCTION: Attempt to write an EA inline if area is available
140 *
141 * PRE CONDITIONS:
142 * Already verified that the specified EA is small enough to fit inline
143 *
144 * PARAMETERS:
145 * ip - Inode pointer
146 * ealist - EA list pointer
147 * size - size of ealist in bytes
148 * ea - dxd_t structure to be filled in with necessary EA information
149 * if we successfully copy the EA inline
150 *
151 * NOTES:
152 * Checks if the inode's inline area is available. If so, copies EA inline
153 * and sets <ea> fields appropriately. Otherwise, returns failure, EA will
154 * have to be put into an extent.
155 *
156 * RETURNS: 0 for successful copy to inline area; -1 if area not available
157 */
158static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist,
159 int size, dxd_t * ea)
160{
161 struct jfs_inode_info *ji = JFS_IP(ip);
162
163 /*
164 * Make sure we have an EA -- the NULL EA list is valid, but you
165 * can't copy it!
166 */
167 if (ealist && size > sizeof (struct jfs_ea_list)) {
168 assert(size <= sizeof (ji->i_inline_ea));
169
170 /*
171 * See if the space is available or if it is already being
172 * used for an inline EA.
173 */
174 if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE))
175 return -EPERM;
176
177 DXDsize(ea, size);
178 DXDlength(ea, 0);
179 DXDaddress(ea, 0);
180 memcpy(ji->i_inline_ea, ealist, size);
181 ea->flag = DXD_INLINE;
182 ji->mode2 &= ~INLINEEA;
183 } else {
184 ea->flag = 0;
185 DXDsize(ea, 0);
186 DXDlength(ea, 0);
187 DXDaddress(ea, 0);
188
189 /* Free up INLINE area */
190 if (ji->ea.flag & DXD_INLINE)
191 ji->mode2 |= INLINEEA;
192 }
193
194 return 0;
195}
196
197/*
198 * NAME: ea_write
199 *
200 * FUNCTION: Write an EA for an inode
201 *
202 * PRE CONDITIONS: EA has been verified
203 *
204 * PARAMETERS:
205 * ip - Inode pointer
206 * ealist - EA list pointer
207 * size - size of ealist in bytes
208 * ea - dxd_t structure to be filled in appropriately with where the
209 * EA was copied
210 *
211 * NOTES: Will write EA inline if able to, otherwise allocates blocks for an
212 * extent and synchronously writes it to those blocks.
213 *
214 * RETURNS: 0 for success; Anything else indicates failure
215 */
216static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size,
217 dxd_t * ea)
218{
219 struct super_block *sb = ip->i_sb;
220 struct jfs_inode_info *ji = JFS_IP(ip);
221 struct jfs_sb_info *sbi = JFS_SBI(sb);
222 int nblocks;
223 s64 blkno;
224 int rc = 0, i;
225 char *cp;
226 s32 nbytes, nb;
227 s32 bytes_to_write;
228 struct metapage *mp;
229
230 /*
231 * Quick check to see if this is an in-linable EA. Short EAs
232 * and empty EAs are all in-linable, provided the space exists.
233 */
234 if (!ealist || size <= sizeof (ji->i_inline_ea)) {
235 if (!ea_write_inline(ip, ealist, size, ea))
236 return 0;
237 }
238
239 /* figure out how many blocks we need */
240 nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
241
242 /* Allocate new blocks to quota. */
243 rc = dquot_alloc_block(ip, nblocks);
244 if (rc)
245 return rc;
246
247 rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
248 if (rc) {
249 /*Rollback quota allocation. */
250 dquot_free_block(ip, nblocks);
251 return rc;
252 }
253
254 /*
255 * Now have nblocks worth of storage to stuff into the FEALIST.
256 * loop over the FEALIST copying data into the buffer one page at
257 * a time.
258 */
259 cp = (char *) ealist;
260 nbytes = size;
261 for (i = 0; i < nblocks; i += sbi->nbperpage) {
262 /*
263 * Determine how many bytes for this request, and round up to
264 * the nearest aggregate block size
265 */
266 nb = min(PSIZE, nbytes);
267 bytes_to_write =
268 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
269 << sb->s_blocksize_bits;
270
271 if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) {
272 rc = -EIO;
273 goto failed;
274 }
275
276 memcpy(mp->data, cp, nb);
277
278 /*
279 * We really need a way to propagate errors for
280 * forced writes like this one. --hch
281 *
282 * (__write_metapage => release_metapage => flush_metapage)
283 */
284#ifdef _JFS_FIXME
285 if ((rc = flush_metapage(mp))) {
286 /*
287 * the write failed -- this means that the buffer
288 * is still assigned and the blocks are not being
289 * used. this seems like the best error recovery
290 * we can get ...
291 */
292 goto failed;
293 }
294#else
295 flush_metapage(mp);
296#endif
297
298 cp += PSIZE;
299 nbytes -= nb;
300 }
301
302 ea->flag = DXD_EXTENT;
303 DXDsize(ea, le32_to_cpu(ealist->size));
304 DXDlength(ea, nblocks);
305 DXDaddress(ea, blkno);
306
307 /* Free up INLINE area */
308 if (ji->ea.flag & DXD_INLINE)
309 ji->mode2 |= INLINEEA;
310
311 return 0;
312
313 failed:
314 /* Rollback quota allocation. */
315 dquot_free_block(ip, nblocks);
316
317 dbFree(ip, blkno, nblocks);
318 return rc;
319}
320
321/*
322 * NAME: ea_read_inline
323 *
324 * FUNCTION: Read an inlined EA into user's buffer
325 *
326 * PARAMETERS:
327 * ip - Inode pointer
328 * ealist - Pointer to buffer to fill in with EA
329 *
330 * RETURNS: 0
331 */
332static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist)
333{
334 struct jfs_inode_info *ji = JFS_IP(ip);
335 int ea_size = sizeDXD(&ji->ea);
336
337 if (ea_size == 0) {
338 ealist->size = 0;
339 return 0;
340 }
341
342 /* Sanity Check */
343 if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea)))
344 return -EIO;
345 if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size)
346 != ea_size)
347 return -EIO;
348
349 memcpy(ealist, ji->i_inline_ea, ea_size);
350 return 0;
351}
352
353/*
354 * NAME: ea_read
355 *
356 * FUNCTION: copy EA data into user's buffer
357 *
358 * PARAMETERS:
359 * ip - Inode pointer
360 * ealist - Pointer to buffer to fill in with EA
361 *
362 * NOTES: If EA is inline calls ea_read_inline() to copy EA.
363 *
364 * RETURNS: 0 for success; other indicates failure
365 */
366static int ea_read(struct inode *ip, struct jfs_ea_list *ealist)
367{
368 struct super_block *sb = ip->i_sb;
369 struct jfs_inode_info *ji = JFS_IP(ip);
370 struct jfs_sb_info *sbi = JFS_SBI(sb);
371 int nblocks;
372 s64 blkno;
373 char *cp = (char *) ealist;
374 int i;
375 int nbytes, nb;
376 s32 bytes_to_read;
377 struct metapage *mp;
378
379 /* quick check for in-line EA */
380 if (ji->ea.flag & DXD_INLINE)
381 return ea_read_inline(ip, ealist);
382
383 nbytes = sizeDXD(&ji->ea);
384 if (!nbytes) {
385 jfs_error(sb, "nbytes is 0\n");
386 return -EIO;
387 }
388
389 /*
390 * Figure out how many blocks were allocated when this EA list was
391 * originally written to disk.
392 */
393 nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage;
394 blkno = addressDXD(&ji->ea) << sbi->l2nbperpage;
395
396 /*
397 * I have found the disk blocks which were originally used to store
398 * the FEALIST. now i loop over each contiguous block copying the
399 * data into the buffer.
400 */
401 for (i = 0; i < nblocks; i += sbi->nbperpage) {
402 /*
403 * Determine how many bytes for this request, and round up to
404 * the nearest aggregate block size
405 */
406 nb = min(PSIZE, nbytes);
407 bytes_to_read =
408 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
409 << sb->s_blocksize_bits;
410
411 if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1)))
412 return -EIO;
413
414 memcpy(cp, mp->data, nb);
415 release_metapage(mp);
416
417 cp += PSIZE;
418 nbytes -= nb;
419 }
420
421 return 0;
422}
423
424/*
425 * NAME: ea_get
426 *
427 * FUNCTION: Returns buffer containing existing extended attributes.
428 * The size of the buffer will be the larger of the existing
429 * attributes size, or min_size.
430 *
431 * The buffer, which may be inlined in the inode or in the
432 * page cache must be release by calling ea_release or ea_put
433 *
434 * PARAMETERS:
435 * inode - Inode pointer
436 * ea_buf - Structure to be populated with ealist and its metadata
437 * min_size- minimum size of buffer to be returned
438 *
439 * RETURNS: 0 for success; Other indicates failure
440 */
441static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
442{
443 struct jfs_inode_info *ji = JFS_IP(inode);
444 struct super_block *sb = inode->i_sb;
445 int size;
446 int ea_size = sizeDXD(&ji->ea);
447 int blocks_needed, current_blocks;
448 s64 blkno;
449 int rc;
450 int quota_allocation = 0;
451
452 /* When fsck.jfs clears a bad ea, it doesn't clear the size */
453 if (ji->ea.flag == 0)
454 ea_size = 0;
455
456 if (ea_size == 0) {
457 if (min_size == 0) {
458 ea_buf->flag = 0;
459 ea_buf->max_size = 0;
460 ea_buf->xattr = NULL;
461 return 0;
462 }
463 if ((min_size <= sizeof (ji->i_inline_ea)) &&
464 (ji->mode2 & INLINEEA)) {
465 ea_buf->flag = EA_INLINE | EA_NEW;
466 ea_buf->max_size = sizeof (ji->i_inline_ea);
467 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
468 DXDlength(&ea_buf->new_ea, 0);
469 DXDaddress(&ea_buf->new_ea, 0);
470 ea_buf->new_ea.flag = DXD_INLINE;
471 DXDsize(&ea_buf->new_ea, min_size);
472 return 0;
473 }
474 current_blocks = 0;
475 } else if (ji->ea.flag & DXD_INLINE) {
476 if (min_size <= sizeof (ji->i_inline_ea)) {
477 ea_buf->flag = EA_INLINE;
478 ea_buf->max_size = sizeof (ji->i_inline_ea);
479 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
480 goto size_check;
481 }
482 current_blocks = 0;
483 } else {
484 if (!(ji->ea.flag & DXD_EXTENT)) {
485 jfs_error(sb, "invalid ea.flag\n");
486 return -EIO;
487 }
488 current_blocks = (ea_size + sb->s_blocksize - 1) >>
489 sb->s_blocksize_bits;
490 }
491 size = max(min_size, ea_size);
492
493 if (size > PSIZE) {
494 /*
495 * To keep the rest of the code simple. Allocate a
496 * contiguous buffer to work with
497 */
498 ea_buf->xattr = kmalloc(size, GFP_KERNEL);
499 if (ea_buf->xattr == NULL)
500 return -ENOMEM;
501
502 ea_buf->flag = EA_MALLOC;
503 ea_buf->max_size = (size + sb->s_blocksize - 1) &
504 ~(sb->s_blocksize - 1);
505
506 if (ea_size == 0)
507 return 0;
508
509 if ((rc = ea_read(inode, ea_buf->xattr))) {
510 kfree(ea_buf->xattr);
511 ea_buf->xattr = NULL;
512 return rc;
513 }
514 goto size_check;
515 }
516 blocks_needed = (min_size + sb->s_blocksize - 1) >>
517 sb->s_blocksize_bits;
518
519 if (blocks_needed > current_blocks) {
520 /* Allocate new blocks to quota. */
521 rc = dquot_alloc_block(inode, blocks_needed);
522 if (rc)
523 return -EDQUOT;
524
525 quota_allocation = blocks_needed;
526
527 rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed,
528 &blkno);
529 if (rc)
530 goto clean_up;
531
532 DXDlength(&ea_buf->new_ea, blocks_needed);
533 DXDaddress(&ea_buf->new_ea, blkno);
534 ea_buf->new_ea.flag = DXD_EXTENT;
535 DXDsize(&ea_buf->new_ea, min_size);
536
537 ea_buf->flag = EA_EXTENT | EA_NEW;
538
539 ea_buf->mp = get_metapage(inode, blkno,
540 blocks_needed << sb->s_blocksize_bits,
541 1);
542 if (ea_buf->mp == NULL) {
543 dbFree(inode, blkno, (s64) blocks_needed);
544 rc = -EIO;
545 goto clean_up;
546 }
547 ea_buf->xattr = ea_buf->mp->data;
548 ea_buf->max_size = (min_size + sb->s_blocksize - 1) &
549 ~(sb->s_blocksize - 1);
550 if (ea_size == 0)
551 return 0;
552 if ((rc = ea_read(inode, ea_buf->xattr))) {
553 discard_metapage(ea_buf->mp);
554 dbFree(inode, blkno, (s64) blocks_needed);
555 goto clean_up;
556 }
557 goto size_check;
558 }
559 ea_buf->flag = EA_EXTENT;
560 ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea),
561 lengthDXD(&ji->ea) << sb->s_blocksize_bits,
562 1);
563 if (ea_buf->mp == NULL) {
564 rc = -EIO;
565 goto clean_up;
566 }
567 ea_buf->xattr = ea_buf->mp->data;
568 ea_buf->max_size = (ea_size + sb->s_blocksize - 1) &
569 ~(sb->s_blocksize - 1);
570
571 size_check:
572 if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
573 printk(KERN_ERR "ea_get: invalid extended attribute\n");
574 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
575 ea_buf->xattr, ea_size, 1);
576 ea_release(inode, ea_buf);
577 rc = -EIO;
578 goto clean_up;
579 }
580
581 return ea_size;
582
583 clean_up:
584 /* Rollback quota allocation */
585 if (quota_allocation)
586 dquot_free_block(inode, quota_allocation);
587
588 return (rc);
589}
590
591static void ea_release(struct inode *inode, struct ea_buffer *ea_buf)
592{
593 if (ea_buf->flag & EA_MALLOC)
594 kfree(ea_buf->xattr);
595 else if (ea_buf->flag & EA_EXTENT) {
596 assert(ea_buf->mp);
597 release_metapage(ea_buf->mp);
598
599 if (ea_buf->flag & EA_NEW)
600 dbFree(inode, addressDXD(&ea_buf->new_ea),
601 lengthDXD(&ea_buf->new_ea));
602 }
603}
604
605static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
606 int new_size)
607{
608 struct jfs_inode_info *ji = JFS_IP(inode);
609 unsigned long old_blocks, new_blocks;
610 int rc = 0;
611
612 if (new_size == 0) {
613 ea_release(inode, ea_buf);
614 ea_buf = NULL;
615 } else if (ea_buf->flag & EA_INLINE) {
616 assert(new_size <= sizeof (ji->i_inline_ea));
617 ji->mode2 &= ~INLINEEA;
618 ea_buf->new_ea.flag = DXD_INLINE;
619 DXDsize(&ea_buf->new_ea, new_size);
620 DXDaddress(&ea_buf->new_ea, 0);
621 DXDlength(&ea_buf->new_ea, 0);
622 } else if (ea_buf->flag & EA_MALLOC) {
623 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
624 kfree(ea_buf->xattr);
625 } else if (ea_buf->flag & EA_NEW) {
626 /* We have already allocated a new dxd */
627 flush_metapage(ea_buf->mp);
628 } else {
629 /* ->xattr must point to original ea's metapage */
630 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
631 discard_metapage(ea_buf->mp);
632 }
633 if (rc)
634 return rc;
635
636 old_blocks = new_blocks = 0;
637
638 if (ji->ea.flag & DXD_EXTENT) {
639 invalidate_dxd_metapages(inode, ji->ea);
640 old_blocks = lengthDXD(&ji->ea);
641 }
642
643 if (ea_buf) {
644 txEA(tid, inode, &ji->ea, &ea_buf->new_ea);
645 if (ea_buf->new_ea.flag & DXD_EXTENT) {
646 new_blocks = lengthDXD(&ea_buf->new_ea);
647 if (ji->ea.flag & DXD_INLINE)
648 ji->mode2 |= INLINEEA;
649 }
650 ji->ea = ea_buf->new_ea;
651 } else {
652 txEA(tid, inode, &ji->ea, NULL);
653 if (ji->ea.flag & DXD_INLINE)
654 ji->mode2 |= INLINEEA;
655 ji->ea.flag = 0;
656 ji->ea.size = 0;
657 }
658
659 /* If old blocks exist, they must be removed from quota allocation. */
660 if (old_blocks)
661 dquot_free_block(inode, old_blocks);
662
663 inode->i_ctime = CURRENT_TIME;
664
665 return 0;
666}
667
668/*
669 * Most of the permission checking is done by xattr_permission in the vfs.
670 * We also need to verify that this is a namespace that we recognize.
671 */
672static int can_set_xattr(struct inode *inode, const char *name,
673 const void *value, size_t value_len)
674{
675 if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) {
676 /*
677 * This makes sure that we aren't trying to set an
678 * attribute in a different namespace by prefixing it
679 * with "os2."
680 */
681 if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN))
682 return -EOPNOTSUPP;
683 return 0;
684 }
685
686 /*
687 * Don't allow setting an attribute in an unknown namespace.
688 */
689 if (strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) &&
690 strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
691 strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
692 return -EOPNOTSUPP;
693
694 return 0;
695}
696
697int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name,
698 const void *value, size_t value_len, int flags)
699{
700 struct jfs_ea_list *ealist;
701 struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL;
702 struct ea_buffer ea_buf;
703 int old_ea_size = 0;
704 int xattr_size;
705 int new_size;
706 int namelen = strlen(name);
707 char *os2name = NULL;
708 int found = 0;
709 int rc;
710 int length;
711
712 if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
713 os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1,
714 GFP_KERNEL);
715 if (!os2name)
716 return -ENOMEM;
717 strcpy(os2name, name + XATTR_OS2_PREFIX_LEN);
718 name = os2name;
719 namelen -= XATTR_OS2_PREFIX_LEN;
720 }
721
722 down_write(&JFS_IP(inode)->xattr_sem);
723
724 xattr_size = ea_get(inode, &ea_buf, 0);
725 if (xattr_size < 0) {
726 rc = xattr_size;
727 goto out;
728 }
729
730 again:
731 ealist = (struct jfs_ea_list *) ea_buf.xattr;
732 new_size = sizeof (struct jfs_ea_list);
733
734 if (xattr_size) {
735 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist);
736 ea = NEXT_EA(ea)) {
737 if ((namelen == ea->namelen) &&
738 (memcmp(name, ea->name, namelen) == 0)) {
739 found = 1;
740 if (flags & XATTR_CREATE) {
741 rc = -EEXIST;
742 goto release;
743 }
744 old_ea = ea;
745 old_ea_size = EA_SIZE(ea);
746 next_ea = NEXT_EA(ea);
747 } else
748 new_size += EA_SIZE(ea);
749 }
750 }
751
752 if (!found) {
753 if (flags & XATTR_REPLACE) {
754 rc = -ENODATA;
755 goto release;
756 }
757 if (value == NULL) {
758 rc = 0;
759 goto release;
760 }
761 }
762 if (value)
763 new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len;
764
765 if (new_size > ea_buf.max_size) {
766 /*
767 * We need to allocate more space for merged ea list.
768 * We should only have loop to again: once.
769 */
770 ea_release(inode, &ea_buf);
771 xattr_size = ea_get(inode, &ea_buf, new_size);
772 if (xattr_size < 0) {
773 rc = xattr_size;
774 goto out;
775 }
776 goto again;
777 }
778
779 /* Remove old ea of the same name */
780 if (found) {
781 /* number of bytes following target EA */
782 length = (char *) END_EALIST(ealist) - (char *) next_ea;
783 if (length > 0)
784 memmove(old_ea, next_ea, length);
785 xattr_size -= old_ea_size;
786 }
787
788 /* Add new entry to the end */
789 if (value) {
790 if (xattr_size == 0)
791 /* Completely new ea list */
792 xattr_size = sizeof (struct jfs_ea_list);
793
794 /*
795 * The size of EA value is limitted by on-disk format up to
796 * __le16, there would be an overflow if the size is equal
797 * to XATTR_SIZE_MAX (65536). In order to avoid this issue,
798 * we can pre-checkup the value size against USHRT_MAX, and
799 * return -E2BIG in this case, which is consistent with the
800 * VFS setxattr interface.
801 */
802 if (value_len >= USHRT_MAX) {
803 rc = -E2BIG;
804 goto release;
805 }
806
807 ea = (struct jfs_ea *) ((char *) ealist + xattr_size);
808 ea->flag = 0;
809 ea->namelen = namelen;
810 ea->valuelen = (cpu_to_le16(value_len));
811 memcpy(ea->name, name, namelen);
812 ea->name[namelen] = 0;
813 if (value_len)
814 memcpy(&ea->name[namelen + 1], value, value_len);
815 xattr_size += EA_SIZE(ea);
816 }
817
818 /* DEBUG - If we did this right, these number match */
819 if (xattr_size != new_size) {
820 printk(KERN_ERR
821 "__jfs_setxattr: xattr_size = %d, new_size = %d\n",
822 xattr_size, new_size);
823
824 rc = -EINVAL;
825 goto release;
826 }
827
828 /*
829 * If we're left with an empty list, there's no ea
830 */
831 if (new_size == sizeof (struct jfs_ea_list))
832 new_size = 0;
833
834 ealist->size = cpu_to_le32(new_size);
835
836 rc = ea_put(tid, inode, &ea_buf, new_size);
837
838 goto out;
839 release:
840 ea_release(inode, &ea_buf);
841 out:
842 up_write(&JFS_IP(inode)->xattr_sem);
843
844 kfree(os2name);
845
846 return rc;
847}
848
849int jfs_setxattr(struct dentry *dentry, const char *name, const void *value,
850 size_t value_len, int flags)
851{
852 struct inode *inode = dentry->d_inode;
853 struct jfs_inode_info *ji = JFS_IP(inode);
854 int rc;
855 tid_t tid;
856
857 /*
858 * If this is a request for a synthetic attribute in the system.*
859 * namespace use the generic infrastructure to resolve a handler
860 * for it via sb->s_xattr.
861 */
862 if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
863 return generic_setxattr(dentry, name, value, value_len, flags);
864
865 if ((rc = can_set_xattr(inode, name, value, value_len)))
866 return rc;
867
868 if (value == NULL) { /* empty EA, do not remove */
869 value = "";
870 value_len = 0;
871 }
872
873 tid = txBegin(inode->i_sb, 0);
874 mutex_lock(&ji->commit_mutex);
875 rc = __jfs_setxattr(tid, dentry->d_inode, name, value, value_len,
876 flags);
877 if (!rc)
878 rc = txCommit(tid, 1, &inode, 0);
879 txEnd(tid);
880 mutex_unlock(&ji->commit_mutex);
881
882 return rc;
883}
884
885ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data,
886 size_t buf_size)
887{
888 struct jfs_ea_list *ealist;
889 struct jfs_ea *ea;
890 struct ea_buffer ea_buf;
891 int xattr_size;
892 ssize_t size;
893 int namelen = strlen(name);
894 char *value;
895
896 down_read(&JFS_IP(inode)->xattr_sem);
897
898 xattr_size = ea_get(inode, &ea_buf, 0);
899
900 if (xattr_size < 0) {
901 size = xattr_size;
902 goto out;
903 }
904
905 if (xattr_size == 0)
906 goto not_found;
907
908 ealist = (struct jfs_ea_list *) ea_buf.xattr;
909
910 /* Find the named attribute */
911 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea))
912 if ((namelen == ea->namelen) &&
913 memcmp(name, ea->name, namelen) == 0) {
914 /* Found it */
915 size = le16_to_cpu(ea->valuelen);
916 if (!data)
917 goto release;
918 else if (size > buf_size) {
919 size = -ERANGE;
920 goto release;
921 }
922 value = ((char *) &ea->name) + ea->namelen + 1;
923 memcpy(data, value, size);
924 goto release;
925 }
926 not_found:
927 size = -ENODATA;
928 release:
929 ea_release(inode, &ea_buf);
930 out:
931 up_read(&JFS_IP(inode)->xattr_sem);
932
933 return size;
934}
935
936ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data,
937 size_t buf_size)
938{
939 int err;
940
941 /*
942 * If this is a request for a synthetic attribute in the system.*
943 * namespace use the generic infrastructure to resolve a handler
944 * for it via sb->s_xattr.
945 */
946 if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
947 return generic_getxattr(dentry, name, data, buf_size);
948
949 if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
950 /*
951 * skip past "os2." prefix
952 */
953 name += XATTR_OS2_PREFIX_LEN;
954 /*
955 * Don't allow retrieving properly prefixed attributes
956 * by prepending them with "os2."
957 */
958 if (is_known_namespace(name))
959 return -EOPNOTSUPP;
960 }
961
962 err = __jfs_getxattr(dentry->d_inode, name, data, buf_size);
963
964 return err;
965}
966
967/*
968 * No special permissions are needed to list attributes except for trusted.*
969 */
970static inline int can_list(struct jfs_ea *ea)
971{
972 return (strncmp(ea->name, XATTR_TRUSTED_PREFIX,
973 XATTR_TRUSTED_PREFIX_LEN) ||
974 capable(CAP_SYS_ADMIN));
975}
976
977ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size)
978{
979 struct inode *inode = dentry->d_inode;
980 char *buffer;
981 ssize_t size = 0;
982 int xattr_size;
983 struct jfs_ea_list *ealist;
984 struct jfs_ea *ea;
985 struct ea_buffer ea_buf;
986
987 down_read(&JFS_IP(inode)->xattr_sem);
988
989 xattr_size = ea_get(inode, &ea_buf, 0);
990 if (xattr_size < 0) {
991 size = xattr_size;
992 goto out;
993 }
994
995 if (xattr_size == 0)
996 goto release;
997
998 ealist = (struct jfs_ea_list *) ea_buf.xattr;
999
1000 /* compute required size of list */
1001 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
1002 if (can_list(ea))
1003 size += name_size(ea) + 1;
1004 }
1005
1006 if (!data)
1007 goto release;
1008
1009 if (size > buf_size) {
1010 size = -ERANGE;
1011 goto release;
1012 }
1013
1014 /* Copy attribute names to buffer */
1015 buffer = data;
1016 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
1017 if (can_list(ea)) {
1018 int namelen = copy_name(buffer, ea);
1019 buffer += namelen + 1;
1020 }
1021 }
1022
1023 release:
1024 ea_release(inode, &ea_buf);
1025 out:
1026 up_read(&JFS_IP(inode)->xattr_sem);
1027 return size;
1028}
1029
1030int jfs_removexattr(struct dentry *dentry, const char *name)
1031{
1032 struct inode *inode = dentry->d_inode;
1033 struct jfs_inode_info *ji = JFS_IP(inode);
1034 int rc;
1035 tid_t tid;
1036
1037 /*
1038 * If this is a request for a synthetic attribute in the system.*
1039 * namespace use the generic infrastructure to resolve a handler
1040 * for it via sb->s_xattr.
1041 */
1042 if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
1043 return generic_removexattr(dentry, name);
1044
1045 if ((rc = can_set_xattr(inode, name, NULL, 0)))
1046 return rc;
1047
1048 tid = txBegin(inode->i_sb, 0);
1049 mutex_lock(&ji->commit_mutex);
1050 rc = __jfs_setxattr(tid, dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
1051 if (!rc)
1052 rc = txCommit(tid, 1, &inode, 0);
1053 txEnd(tid);
1054 mutex_unlock(&ji->commit_mutex);
1055
1056 return rc;
1057}
1058
1059/*
1060 * List of handlers for synthetic system.* attributes. All real ondisk
1061 * attributes are handled directly.
1062 */
1063const struct xattr_handler *jfs_xattr_handlers[] = {
1064#ifdef CONFIG_JFS_POSIX_ACL
1065 &posix_acl_access_xattr_handler,
1066 &posix_acl_default_xattr_handler,
1067#endif
1068 NULL,
1069};
1070
1071
1072#ifdef CONFIG_JFS_SECURITY
1073static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
1074 void *fs_info)
1075{
1076 const struct xattr *xattr;
1077 tid_t *tid = fs_info;
1078 char *name;
1079 int err = 0;
1080
1081 for (xattr = xattr_array; xattr->name != NULL; xattr++) {
1082 name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
1083 strlen(xattr->name) + 1, GFP_NOFS);
1084 if (!name) {
1085 err = -ENOMEM;
1086 break;
1087 }
1088 strcpy(name, XATTR_SECURITY_PREFIX);
1089 strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
1090
1091 err = __jfs_setxattr(*tid, inode, name,
1092 xattr->value, xattr->value_len, 0);
1093 kfree(name);
1094 if (err < 0)
1095 break;
1096 }
1097 return err;
1098}
1099
1100int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
1101 const struct qstr *qstr)
1102{
1103 return security_inode_init_security(inode, dir, qstr,
1104 &jfs_initxattrs, &tid);
1105}
1106#endif
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) International Business Machines Corp., 2000-2004
4 * Copyright (C) Christoph Hellwig, 2002
5 */
6
7#include <linux/capability.h>
8#include <linux/fs.h>
9#include <linux/xattr.h>
10#include <linux/posix_acl_xattr.h>
11#include <linux/slab.h>
12#include <linux/quotaops.h>
13#include <linux/security.h>
14#include "jfs_incore.h"
15#include "jfs_superblock.h"
16#include "jfs_dmap.h"
17#include "jfs_debug.h"
18#include "jfs_dinode.h"
19#include "jfs_extent.h"
20#include "jfs_metapage.h"
21#include "jfs_xattr.h"
22#include "jfs_acl.h"
23
24/*
25 * jfs_xattr.c: extended attribute service
26 *
27 * Overall design --
28 *
29 * Format:
30 *
31 * Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit
32 * value) and a variable (0 or more) number of extended attribute
33 * entries. Each extended attribute entry (jfs_ea) is a <name,value> double
34 * where <name> is constructed from a null-terminated ascii string
35 * (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data
36 * (1 ... 65535 bytes). The in-memory format is
37 *
38 * 0 1 2 4 4 + namelen + 1
39 * +-------+--------+--------+----------------+-------------------+
40 * | Flags | Name | Value | Name String \0 | Data . . . . |
41 * | | Length | Length | | |
42 * +-------+--------+--------+----------------+-------------------+
43 *
44 * A jfs_ea_list then is structured as
45 *
46 * 0 4 4 + EA_SIZE(ea1)
47 * +------------+-------------------+--------------------+-----
48 * | Overall EA | First FEA Element | Second FEA Element | .....
49 * | List Size | | |
50 * +------------+-------------------+--------------------+-----
51 *
52 * On-disk:
53 *
54 * FEALISTs are stored on disk using blocks allocated by dbAlloc() and
55 * written directly. An EA list may be in-lined in the inode if there is
56 * sufficient room available.
57 */
58
59struct ea_buffer {
60 int flag; /* Indicates what storage xattr points to */
61 int max_size; /* largest xattr that fits in current buffer */
62 dxd_t new_ea; /* dxd to replace ea when modifying xattr */
63 struct metapage *mp; /* metapage containing ea list */
64 struct jfs_ea_list *xattr; /* buffer containing ea list */
65};
66
67/*
68 * ea_buffer.flag values
69 */
70#define EA_INLINE 0x0001
71#define EA_EXTENT 0x0002
72#define EA_NEW 0x0004
73#define EA_MALLOC 0x0008
74
75
76/*
77 * Mapping of on-disk attribute names: for on-disk attribute names with an
78 * unknown prefix (not "system.", "user.", "security.", or "trusted."), the
79 * prefix "os2." is prepended. On the way back to disk, "os2." prefixes are
80 * stripped and we make sure that the remaining name does not start with one
81 * of the know prefixes.
82 */
83
84static int is_known_namespace(const char *name)
85{
86 if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
87 strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
88 strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
89 strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
90 return false;
91
92 return true;
93}
94
95static inline int name_size(struct jfs_ea *ea)
96{
97 if (is_known_namespace(ea->name))
98 return ea->namelen;
99 else
100 return ea->namelen + XATTR_OS2_PREFIX_LEN;
101}
102
103static inline int copy_name(char *buffer, struct jfs_ea *ea)
104{
105 int len = ea->namelen;
106
107 if (!is_known_namespace(ea->name)) {
108 memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN);
109 buffer += XATTR_OS2_PREFIX_LEN;
110 len += XATTR_OS2_PREFIX_LEN;
111 }
112 memcpy(buffer, ea->name, ea->namelen);
113 buffer[ea->namelen] = 0;
114
115 return len;
116}
117
118/* Forward references */
119static void ea_release(struct inode *inode, struct ea_buffer *ea_buf);
120
121/*
122 * NAME: ea_write_inline
123 *
124 * FUNCTION: Attempt to write an EA inline if area is available
125 *
126 * PRE CONDITIONS:
127 * Already verified that the specified EA is small enough to fit inline
128 *
129 * PARAMETERS:
130 * ip - Inode pointer
131 * ealist - EA list pointer
132 * size - size of ealist in bytes
133 * ea - dxd_t structure to be filled in with necessary EA information
134 * if we successfully copy the EA inline
135 *
136 * NOTES:
137 * Checks if the inode's inline area is available. If so, copies EA inline
138 * and sets <ea> fields appropriately. Otherwise, returns failure, EA will
139 * have to be put into an extent.
140 *
141 * RETURNS: 0 for successful copy to inline area; -1 if area not available
142 */
143static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist,
144 int size, dxd_t * ea)
145{
146 struct jfs_inode_info *ji = JFS_IP(ip);
147
148 /*
149 * Make sure we have an EA -- the NULL EA list is valid, but you
150 * can't copy it!
151 */
152 if (ealist && size > sizeof (struct jfs_ea_list)) {
153 assert(size <= sizeof (ji->i_inline_ea));
154
155 /*
156 * See if the space is available or if it is already being
157 * used for an inline EA.
158 */
159 if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE))
160 return -EPERM;
161
162 DXDsize(ea, size);
163 DXDlength(ea, 0);
164 DXDaddress(ea, 0);
165 memcpy(ji->i_inline_ea, ealist, size);
166 ea->flag = DXD_INLINE;
167 ji->mode2 &= ~INLINEEA;
168 } else {
169 ea->flag = 0;
170 DXDsize(ea, 0);
171 DXDlength(ea, 0);
172 DXDaddress(ea, 0);
173
174 /* Free up INLINE area */
175 if (ji->ea.flag & DXD_INLINE)
176 ji->mode2 |= INLINEEA;
177 }
178
179 return 0;
180}
181
182/*
183 * NAME: ea_write
184 *
185 * FUNCTION: Write an EA for an inode
186 *
187 * PRE CONDITIONS: EA has been verified
188 *
189 * PARAMETERS:
190 * ip - Inode pointer
191 * ealist - EA list pointer
192 * size - size of ealist in bytes
193 * ea - dxd_t structure to be filled in appropriately with where the
194 * EA was copied
195 *
196 * NOTES: Will write EA inline if able to, otherwise allocates blocks for an
197 * extent and synchronously writes it to those blocks.
198 *
199 * RETURNS: 0 for success; Anything else indicates failure
200 */
201static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size,
202 dxd_t * ea)
203{
204 struct super_block *sb = ip->i_sb;
205 struct jfs_inode_info *ji = JFS_IP(ip);
206 struct jfs_sb_info *sbi = JFS_SBI(sb);
207 int nblocks;
208 s64 blkno;
209 int rc = 0, i;
210 char *cp;
211 s32 nbytes, nb;
212 s32 bytes_to_write;
213 struct metapage *mp;
214
215 /*
216 * Quick check to see if this is an in-linable EA. Short EAs
217 * and empty EAs are all in-linable, provided the space exists.
218 */
219 if (!ealist || size <= sizeof (ji->i_inline_ea)) {
220 if (!ea_write_inline(ip, ealist, size, ea))
221 return 0;
222 }
223
224 /* figure out how many blocks we need */
225 nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
226
227 /* Allocate new blocks to quota. */
228 rc = dquot_alloc_block(ip, nblocks);
229 if (rc)
230 return rc;
231
232 rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
233 if (rc) {
234 /*Rollback quota allocation. */
235 dquot_free_block(ip, nblocks);
236 return rc;
237 }
238
239 /*
240 * Now have nblocks worth of storage to stuff into the FEALIST.
241 * loop over the FEALIST copying data into the buffer one page at
242 * a time.
243 */
244 cp = (char *) ealist;
245 nbytes = size;
246 for (i = 0; i < nblocks; i += sbi->nbperpage) {
247 /*
248 * Determine how many bytes for this request, and round up to
249 * the nearest aggregate block size
250 */
251 nb = min(PSIZE, nbytes);
252 bytes_to_write =
253 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
254 << sb->s_blocksize_bits;
255
256 if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) {
257 rc = -EIO;
258 goto failed;
259 }
260
261 memcpy(mp->data, cp, nb);
262
263 /*
264 * We really need a way to propagate errors for
265 * forced writes like this one. --hch
266 *
267 * (__write_metapage => release_metapage => flush_metapage)
268 */
269#ifdef _JFS_FIXME
270 if ((rc = flush_metapage(mp))) {
271 /*
272 * the write failed -- this means that the buffer
273 * is still assigned and the blocks are not being
274 * used. this seems like the best error recovery
275 * we can get ...
276 */
277 goto failed;
278 }
279#else
280 flush_metapage(mp);
281#endif
282
283 cp += PSIZE;
284 nbytes -= nb;
285 }
286
287 ea->flag = DXD_EXTENT;
288 DXDsize(ea, le32_to_cpu(ealist->size));
289 DXDlength(ea, nblocks);
290 DXDaddress(ea, blkno);
291
292 /* Free up INLINE area */
293 if (ji->ea.flag & DXD_INLINE)
294 ji->mode2 |= INLINEEA;
295
296 return 0;
297
298 failed:
299 /* Rollback quota allocation. */
300 dquot_free_block(ip, nblocks);
301
302 dbFree(ip, blkno, nblocks);
303 return rc;
304}
305
306/*
307 * NAME: ea_read_inline
308 *
309 * FUNCTION: Read an inlined EA into user's buffer
310 *
311 * PARAMETERS:
312 * ip - Inode pointer
313 * ealist - Pointer to buffer to fill in with EA
314 *
315 * RETURNS: 0
316 */
317static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist)
318{
319 struct jfs_inode_info *ji = JFS_IP(ip);
320 int ea_size = sizeDXD(&ji->ea);
321
322 if (ea_size == 0) {
323 ealist->size = 0;
324 return 0;
325 }
326
327 /* Sanity Check */
328 if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea)))
329 return -EIO;
330 if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size)
331 != ea_size)
332 return -EIO;
333
334 memcpy(ealist, ji->i_inline_ea, ea_size);
335 return 0;
336}
337
338/*
339 * NAME: ea_read
340 *
341 * FUNCTION: copy EA data into user's buffer
342 *
343 * PARAMETERS:
344 * ip - Inode pointer
345 * ealist - Pointer to buffer to fill in with EA
346 *
347 * NOTES: If EA is inline calls ea_read_inline() to copy EA.
348 *
349 * RETURNS: 0 for success; other indicates failure
350 */
351static int ea_read(struct inode *ip, struct jfs_ea_list *ealist)
352{
353 struct super_block *sb = ip->i_sb;
354 struct jfs_inode_info *ji = JFS_IP(ip);
355 struct jfs_sb_info *sbi = JFS_SBI(sb);
356 int nblocks;
357 s64 blkno;
358 char *cp = (char *) ealist;
359 int i;
360 int nbytes, nb;
361 s32 bytes_to_read;
362 struct metapage *mp;
363
364 /* quick check for in-line EA */
365 if (ji->ea.flag & DXD_INLINE)
366 return ea_read_inline(ip, ealist);
367
368 nbytes = sizeDXD(&ji->ea);
369 if (!nbytes) {
370 jfs_error(sb, "nbytes is 0\n");
371 return -EIO;
372 }
373
374 /*
375 * Figure out how many blocks were allocated when this EA list was
376 * originally written to disk.
377 */
378 nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage;
379 blkno = addressDXD(&ji->ea) << sbi->l2nbperpage;
380
381 /*
382 * I have found the disk blocks which were originally used to store
383 * the FEALIST. now i loop over each contiguous block copying the
384 * data into the buffer.
385 */
386 for (i = 0; i < nblocks; i += sbi->nbperpage) {
387 /*
388 * Determine how many bytes for this request, and round up to
389 * the nearest aggregate block size
390 */
391 nb = min(PSIZE, nbytes);
392 bytes_to_read =
393 ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
394 << sb->s_blocksize_bits;
395
396 if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1)))
397 return -EIO;
398
399 memcpy(cp, mp->data, nb);
400 release_metapage(mp);
401
402 cp += PSIZE;
403 nbytes -= nb;
404 }
405
406 return 0;
407}
408
409/*
410 * NAME: ea_get
411 *
412 * FUNCTION: Returns buffer containing existing extended attributes.
413 * The size of the buffer will be the larger of the existing
414 * attributes size, or min_size.
415 *
416 * The buffer, which may be inlined in the inode or in the
417 * page cache must be release by calling ea_release or ea_put
418 *
419 * PARAMETERS:
420 * inode - Inode pointer
421 * ea_buf - Structure to be populated with ealist and its metadata
422 * min_size- minimum size of buffer to be returned
423 *
424 * RETURNS: 0 for success; Other indicates failure
425 */
426static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
427{
428 struct jfs_inode_info *ji = JFS_IP(inode);
429 struct super_block *sb = inode->i_sb;
430 int size;
431 int ea_size = sizeDXD(&ji->ea);
432 int blocks_needed, current_blocks;
433 s64 blkno;
434 int rc;
435 int quota_allocation = 0;
436
437 /* When fsck.jfs clears a bad ea, it doesn't clear the size */
438 if (ji->ea.flag == 0)
439 ea_size = 0;
440
441 if (ea_size == 0) {
442 if (min_size == 0) {
443 ea_buf->flag = 0;
444 ea_buf->max_size = 0;
445 ea_buf->xattr = NULL;
446 return 0;
447 }
448 if ((min_size <= sizeof (ji->i_inline_ea)) &&
449 (ji->mode2 & INLINEEA)) {
450 ea_buf->flag = EA_INLINE | EA_NEW;
451 ea_buf->max_size = sizeof (ji->i_inline_ea);
452 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
453 DXDlength(&ea_buf->new_ea, 0);
454 DXDaddress(&ea_buf->new_ea, 0);
455 ea_buf->new_ea.flag = DXD_INLINE;
456 DXDsize(&ea_buf->new_ea, min_size);
457 return 0;
458 }
459 current_blocks = 0;
460 } else if (ji->ea.flag & DXD_INLINE) {
461 if (min_size <= sizeof (ji->i_inline_ea)) {
462 ea_buf->flag = EA_INLINE;
463 ea_buf->max_size = sizeof (ji->i_inline_ea);
464 ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
465 goto size_check;
466 }
467 current_blocks = 0;
468 } else {
469 if (!(ji->ea.flag & DXD_EXTENT)) {
470 jfs_error(sb, "invalid ea.flag\n");
471 return -EIO;
472 }
473 current_blocks = (ea_size + sb->s_blocksize - 1) >>
474 sb->s_blocksize_bits;
475 }
476 size = max(min_size, ea_size);
477
478 if (size > PSIZE) {
479 /*
480 * To keep the rest of the code simple. Allocate a
481 * contiguous buffer to work with. Make the buffer large
482 * enough to make use of the whole extent.
483 */
484 ea_buf->max_size = (size + sb->s_blocksize - 1) &
485 ~(sb->s_blocksize - 1);
486
487 ea_buf->xattr = kmalloc(ea_buf->max_size, GFP_KERNEL);
488 if (ea_buf->xattr == NULL)
489 return -ENOMEM;
490
491 ea_buf->flag = EA_MALLOC;
492
493 if (ea_size == 0)
494 return 0;
495
496 if ((rc = ea_read(inode, ea_buf->xattr))) {
497 kfree(ea_buf->xattr);
498 ea_buf->xattr = NULL;
499 return rc;
500 }
501 goto size_check;
502 }
503 blocks_needed = (min_size + sb->s_blocksize - 1) >>
504 sb->s_blocksize_bits;
505
506 if (blocks_needed > current_blocks) {
507 /* Allocate new blocks to quota. */
508 rc = dquot_alloc_block(inode, blocks_needed);
509 if (rc)
510 return -EDQUOT;
511
512 quota_allocation = blocks_needed;
513
514 rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed,
515 &blkno);
516 if (rc)
517 goto clean_up;
518
519 DXDlength(&ea_buf->new_ea, blocks_needed);
520 DXDaddress(&ea_buf->new_ea, blkno);
521 ea_buf->new_ea.flag = DXD_EXTENT;
522 DXDsize(&ea_buf->new_ea, min_size);
523
524 ea_buf->flag = EA_EXTENT | EA_NEW;
525
526 ea_buf->mp = get_metapage(inode, blkno,
527 blocks_needed << sb->s_blocksize_bits,
528 1);
529 if (ea_buf->mp == NULL) {
530 dbFree(inode, blkno, (s64) blocks_needed);
531 rc = -EIO;
532 goto clean_up;
533 }
534 ea_buf->xattr = ea_buf->mp->data;
535 ea_buf->max_size = (min_size + sb->s_blocksize - 1) &
536 ~(sb->s_blocksize - 1);
537 if (ea_size == 0)
538 return 0;
539 if ((rc = ea_read(inode, ea_buf->xattr))) {
540 discard_metapage(ea_buf->mp);
541 dbFree(inode, blkno, (s64) blocks_needed);
542 goto clean_up;
543 }
544 goto size_check;
545 }
546 ea_buf->flag = EA_EXTENT;
547 ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea),
548 lengthDXD(&ji->ea) << sb->s_blocksize_bits,
549 1);
550 if (ea_buf->mp == NULL) {
551 rc = -EIO;
552 goto clean_up;
553 }
554 ea_buf->xattr = ea_buf->mp->data;
555 ea_buf->max_size = (ea_size + sb->s_blocksize - 1) &
556 ~(sb->s_blocksize - 1);
557
558 size_check:
559 if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
560 printk(KERN_ERR "ea_get: invalid extended attribute\n");
561 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
562 ea_buf->xattr, ea_size, 1);
563 ea_release(inode, ea_buf);
564 rc = -EIO;
565 goto clean_up;
566 }
567
568 return ea_size;
569
570 clean_up:
571 /* Rollback quota allocation */
572 if (quota_allocation)
573 dquot_free_block(inode, quota_allocation);
574
575 return (rc);
576}
577
578static void ea_release(struct inode *inode, struct ea_buffer *ea_buf)
579{
580 if (ea_buf->flag & EA_MALLOC)
581 kfree(ea_buf->xattr);
582 else if (ea_buf->flag & EA_EXTENT) {
583 assert(ea_buf->mp);
584 release_metapage(ea_buf->mp);
585
586 if (ea_buf->flag & EA_NEW)
587 dbFree(inode, addressDXD(&ea_buf->new_ea),
588 lengthDXD(&ea_buf->new_ea));
589 }
590}
591
592static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
593 int new_size)
594{
595 struct jfs_inode_info *ji = JFS_IP(inode);
596 unsigned long old_blocks, new_blocks;
597 int rc = 0;
598
599 if (new_size == 0) {
600 ea_release(inode, ea_buf);
601 ea_buf = NULL;
602 } else if (ea_buf->flag & EA_INLINE) {
603 assert(new_size <= sizeof (ji->i_inline_ea));
604 ji->mode2 &= ~INLINEEA;
605 ea_buf->new_ea.flag = DXD_INLINE;
606 DXDsize(&ea_buf->new_ea, new_size);
607 DXDaddress(&ea_buf->new_ea, 0);
608 DXDlength(&ea_buf->new_ea, 0);
609 } else if (ea_buf->flag & EA_MALLOC) {
610 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
611 kfree(ea_buf->xattr);
612 } else if (ea_buf->flag & EA_NEW) {
613 /* We have already allocated a new dxd */
614 flush_metapage(ea_buf->mp);
615 } else {
616 /* ->xattr must point to original ea's metapage */
617 rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
618 discard_metapage(ea_buf->mp);
619 }
620 if (rc)
621 return rc;
622
623 old_blocks = new_blocks = 0;
624
625 if (ji->ea.flag & DXD_EXTENT) {
626 invalidate_dxd_metapages(inode, ji->ea);
627 old_blocks = lengthDXD(&ji->ea);
628 }
629
630 if (ea_buf) {
631 txEA(tid, inode, &ji->ea, &ea_buf->new_ea);
632 if (ea_buf->new_ea.flag & DXD_EXTENT) {
633 new_blocks = lengthDXD(&ea_buf->new_ea);
634 if (ji->ea.flag & DXD_INLINE)
635 ji->mode2 |= INLINEEA;
636 }
637 ji->ea = ea_buf->new_ea;
638 } else {
639 txEA(tid, inode, &ji->ea, NULL);
640 if (ji->ea.flag & DXD_INLINE)
641 ji->mode2 |= INLINEEA;
642 ji->ea.flag = 0;
643 ji->ea.size = 0;
644 }
645
646 /* If old blocks exist, they must be removed from quota allocation. */
647 if (old_blocks)
648 dquot_free_block(inode, old_blocks);
649
650 inode->i_ctime = current_time(inode);
651
652 return 0;
653}
654
655int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name,
656 const void *value, size_t value_len, int flags)
657{
658 struct jfs_ea_list *ealist;
659 struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL;
660 struct ea_buffer ea_buf;
661 int old_ea_size = 0;
662 int xattr_size;
663 int new_size;
664 int namelen = strlen(name);
665 int found = 0;
666 int rc;
667 int length;
668
669 down_write(&JFS_IP(inode)->xattr_sem);
670
671 xattr_size = ea_get(inode, &ea_buf, 0);
672 if (xattr_size < 0) {
673 rc = xattr_size;
674 goto out;
675 }
676
677 again:
678 ealist = (struct jfs_ea_list *) ea_buf.xattr;
679 new_size = sizeof (struct jfs_ea_list);
680
681 if (xattr_size) {
682 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist);
683 ea = NEXT_EA(ea)) {
684 if ((namelen == ea->namelen) &&
685 (memcmp(name, ea->name, namelen) == 0)) {
686 found = 1;
687 if (flags & XATTR_CREATE) {
688 rc = -EEXIST;
689 goto release;
690 }
691 old_ea = ea;
692 old_ea_size = EA_SIZE(ea);
693 next_ea = NEXT_EA(ea);
694 } else
695 new_size += EA_SIZE(ea);
696 }
697 }
698
699 if (!found) {
700 if (flags & XATTR_REPLACE) {
701 rc = -ENODATA;
702 goto release;
703 }
704 if (value == NULL) {
705 rc = 0;
706 goto release;
707 }
708 }
709 if (value)
710 new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len;
711
712 if (new_size > ea_buf.max_size) {
713 /*
714 * We need to allocate more space for merged ea list.
715 * We should only have loop to again: once.
716 */
717 ea_release(inode, &ea_buf);
718 xattr_size = ea_get(inode, &ea_buf, new_size);
719 if (xattr_size < 0) {
720 rc = xattr_size;
721 goto out;
722 }
723 goto again;
724 }
725
726 /* Remove old ea of the same name */
727 if (found) {
728 /* number of bytes following target EA */
729 length = (char *) END_EALIST(ealist) - (char *) next_ea;
730 if (length > 0)
731 memmove(old_ea, next_ea, length);
732 xattr_size -= old_ea_size;
733 }
734
735 /* Add new entry to the end */
736 if (value) {
737 if (xattr_size == 0)
738 /* Completely new ea list */
739 xattr_size = sizeof (struct jfs_ea_list);
740
741 /*
742 * The size of EA value is limitted by on-disk format up to
743 * __le16, there would be an overflow if the size is equal
744 * to XATTR_SIZE_MAX (65536). In order to avoid this issue,
745 * we can pre-checkup the value size against USHRT_MAX, and
746 * return -E2BIG in this case, which is consistent with the
747 * VFS setxattr interface.
748 */
749 if (value_len >= USHRT_MAX) {
750 rc = -E2BIG;
751 goto release;
752 }
753
754 ea = (struct jfs_ea *) ((char *) ealist + xattr_size);
755 ea->flag = 0;
756 ea->namelen = namelen;
757 ea->valuelen = (cpu_to_le16(value_len));
758 memcpy(ea->name, name, namelen);
759 ea->name[namelen] = 0;
760 if (value_len)
761 memcpy(&ea->name[namelen + 1], value, value_len);
762 xattr_size += EA_SIZE(ea);
763 }
764
765 /* DEBUG - If we did this right, these number match */
766 if (xattr_size != new_size) {
767 printk(KERN_ERR
768 "__jfs_setxattr: xattr_size = %d, new_size = %d\n",
769 xattr_size, new_size);
770
771 rc = -EINVAL;
772 goto release;
773 }
774
775 /*
776 * If we're left with an empty list, there's no ea
777 */
778 if (new_size == sizeof (struct jfs_ea_list))
779 new_size = 0;
780
781 ealist->size = cpu_to_le32(new_size);
782
783 rc = ea_put(tid, inode, &ea_buf, new_size);
784
785 goto out;
786 release:
787 ea_release(inode, &ea_buf);
788 out:
789 up_write(&JFS_IP(inode)->xattr_sem);
790
791 return rc;
792}
793
794ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data,
795 size_t buf_size)
796{
797 struct jfs_ea_list *ealist;
798 struct jfs_ea *ea;
799 struct ea_buffer ea_buf;
800 int xattr_size;
801 ssize_t size;
802 int namelen = strlen(name);
803 char *value;
804
805 down_read(&JFS_IP(inode)->xattr_sem);
806
807 xattr_size = ea_get(inode, &ea_buf, 0);
808
809 if (xattr_size < 0) {
810 size = xattr_size;
811 goto out;
812 }
813
814 if (xattr_size == 0)
815 goto not_found;
816
817 ealist = (struct jfs_ea_list *) ea_buf.xattr;
818
819 /* Find the named attribute */
820 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea))
821 if ((namelen == ea->namelen) &&
822 memcmp(name, ea->name, namelen) == 0) {
823 /* Found it */
824 size = le16_to_cpu(ea->valuelen);
825 if (!data)
826 goto release;
827 else if (size > buf_size) {
828 size = -ERANGE;
829 goto release;
830 }
831 value = ((char *) &ea->name) + ea->namelen + 1;
832 memcpy(data, value, size);
833 goto release;
834 }
835 not_found:
836 size = -ENODATA;
837 release:
838 ea_release(inode, &ea_buf);
839 out:
840 up_read(&JFS_IP(inode)->xattr_sem);
841
842 return size;
843}
844
845/*
846 * No special permissions are needed to list attributes except for trusted.*
847 */
848static inline int can_list(struct jfs_ea *ea)
849{
850 return (strncmp(ea->name, XATTR_TRUSTED_PREFIX,
851 XATTR_TRUSTED_PREFIX_LEN) ||
852 capable(CAP_SYS_ADMIN));
853}
854
855ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size)
856{
857 struct inode *inode = d_inode(dentry);
858 char *buffer;
859 ssize_t size = 0;
860 int xattr_size;
861 struct jfs_ea_list *ealist;
862 struct jfs_ea *ea;
863 struct ea_buffer ea_buf;
864
865 down_read(&JFS_IP(inode)->xattr_sem);
866
867 xattr_size = ea_get(inode, &ea_buf, 0);
868 if (xattr_size < 0) {
869 size = xattr_size;
870 goto out;
871 }
872
873 if (xattr_size == 0)
874 goto release;
875
876 ealist = (struct jfs_ea_list *) ea_buf.xattr;
877
878 /* compute required size of list */
879 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
880 if (can_list(ea))
881 size += name_size(ea) + 1;
882 }
883
884 if (!data)
885 goto release;
886
887 if (size > buf_size) {
888 size = -ERANGE;
889 goto release;
890 }
891
892 /* Copy attribute names to buffer */
893 buffer = data;
894 for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
895 if (can_list(ea)) {
896 int namelen = copy_name(buffer, ea);
897 buffer += namelen + 1;
898 }
899 }
900
901 release:
902 ea_release(inode, &ea_buf);
903 out:
904 up_read(&JFS_IP(inode)->xattr_sem);
905 return size;
906}
907
908static int __jfs_xattr_set(struct inode *inode, const char *name,
909 const void *value, size_t size, int flags)
910{
911 struct jfs_inode_info *ji = JFS_IP(inode);
912 tid_t tid;
913 int rc;
914
915 tid = txBegin(inode->i_sb, 0);
916 mutex_lock(&ji->commit_mutex);
917 rc = __jfs_setxattr(tid, inode, name, value, size, flags);
918 if (!rc)
919 rc = txCommit(tid, 1, &inode, 0);
920 txEnd(tid);
921 mutex_unlock(&ji->commit_mutex);
922
923 return rc;
924}
925
926static int jfs_xattr_get(const struct xattr_handler *handler,
927 struct dentry *unused, struct inode *inode,
928 const char *name, void *value, size_t size)
929{
930 name = xattr_full_name(handler, name);
931 return __jfs_getxattr(inode, name, value, size);
932}
933
934static int jfs_xattr_set(const struct xattr_handler *handler,
935 struct user_namespace *mnt_userns,
936 struct dentry *unused, struct inode *inode,
937 const char *name, const void *value,
938 size_t size, int flags)
939{
940 name = xattr_full_name(handler, name);
941 return __jfs_xattr_set(inode, name, value, size, flags);
942}
943
944static int jfs_xattr_get_os2(const struct xattr_handler *handler,
945 struct dentry *unused, struct inode *inode,
946 const char *name, void *value, size_t size)
947{
948 if (is_known_namespace(name))
949 return -EOPNOTSUPP;
950 return __jfs_getxattr(inode, name, value, size);
951}
952
953static int jfs_xattr_set_os2(const struct xattr_handler *handler,
954 struct user_namespace *mnt_userns,
955 struct dentry *unused, struct inode *inode,
956 const char *name, const void *value,
957 size_t size, int flags)
958{
959 if (is_known_namespace(name))
960 return -EOPNOTSUPP;
961 return __jfs_xattr_set(inode, name, value, size, flags);
962}
963
964static const struct xattr_handler jfs_user_xattr_handler = {
965 .prefix = XATTR_USER_PREFIX,
966 .get = jfs_xattr_get,
967 .set = jfs_xattr_set,
968};
969
970static const struct xattr_handler jfs_os2_xattr_handler = {
971 .prefix = XATTR_OS2_PREFIX,
972 .get = jfs_xattr_get_os2,
973 .set = jfs_xattr_set_os2,
974};
975
976static const struct xattr_handler jfs_security_xattr_handler = {
977 .prefix = XATTR_SECURITY_PREFIX,
978 .get = jfs_xattr_get,
979 .set = jfs_xattr_set,
980};
981
982static const struct xattr_handler jfs_trusted_xattr_handler = {
983 .prefix = XATTR_TRUSTED_PREFIX,
984 .get = jfs_xattr_get,
985 .set = jfs_xattr_set,
986};
987
988const struct xattr_handler *jfs_xattr_handlers[] = {
989#ifdef CONFIG_JFS_POSIX_ACL
990 &posix_acl_access_xattr_handler,
991 &posix_acl_default_xattr_handler,
992#endif
993 &jfs_os2_xattr_handler,
994 &jfs_user_xattr_handler,
995 &jfs_security_xattr_handler,
996 &jfs_trusted_xattr_handler,
997 NULL,
998};
999
1000
1001#ifdef CONFIG_JFS_SECURITY
1002static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
1003 void *fs_info)
1004{
1005 const struct xattr *xattr;
1006 tid_t *tid = fs_info;
1007 char *name;
1008 int err = 0;
1009
1010 for (xattr = xattr_array; xattr->name != NULL; xattr++) {
1011 name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
1012 strlen(xattr->name) + 1, GFP_NOFS);
1013 if (!name) {
1014 err = -ENOMEM;
1015 break;
1016 }
1017 strcpy(name, XATTR_SECURITY_PREFIX);
1018 strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
1019
1020 err = __jfs_setxattr(*tid, inode, name,
1021 xattr->value, xattr->value_len, 0);
1022 kfree(name);
1023 if (err < 0)
1024 break;
1025 }
1026 return err;
1027}
1028
1029int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
1030 const struct qstr *qstr)
1031{
1032 return security_inode_init_security(inode, dir, qstr,
1033 &jfs_initxattrs, &tid);
1034}
1035#endif