1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_bit.h"
25 #include "xfs_mount.h"
26 #include "xfs_defer.h"
27 #include "xfs_da_format.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_attr_sf.h"
30 #include "xfs_inode.h"
31 #include "xfs_alloc.h"
32 #include "xfs_trans.h"
33 #include "xfs_inode_item.h"
34 #include "xfs_bmap.h"
35 #include "xfs_bmap_util.h"
36 #include "xfs_bmap_btree.h"
37 #include "xfs_attr.h"
38 #include "xfs_attr_leaf.h"
39 #include "xfs_attr_remote.h"
40 #include "xfs_error.h"
41 #include "xfs_quota.h"
42 #include "xfs_trans_space.h"
43 #include "xfs_trace.h"
44
45 /*
46 * xfs_attr.c
47 *
48 * Provide the external interfaces to manage attribute lists.
49 */
50
51 /*========================================================================
52 * Function prototypes for the kernel.
53 *========================================================================*/
54
55 /*
56 * Internal routines when attribute list fits inside the inode.
57 */
58 STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
59
60 /*
61 * Internal routines when attribute list is one block.
62 */
63 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
64 STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
65 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
66
67 /*
68 * Internal routines when attribute list is more than one block.
69 */
70 STATIC int xfs_attr_node_get(xfs_da_args_t *args);
71 STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
72 STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
73 STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
74 STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
75
76
77 STATIC int
xfs_attr_args_init(struct xfs_da_args * args,struct xfs_inode * dp,const unsigned char * name,int flags)78 xfs_attr_args_init(
79 struct xfs_da_args *args,
80 struct xfs_inode *dp,
81 const unsigned char *name,
82 int flags)
83 {
84
85 if (!name)
86 return -EINVAL;
87
88 memset(args, 0, sizeof(*args));
89 args->geo = dp->i_mount->m_attr_geo;
90 args->whichfork = XFS_ATTR_FORK;
91 args->dp = dp;
92 args->flags = flags;
93 args->name = name;
94 args->namelen = strlen((const char *)name);
95 if (args->namelen >= MAXNAMELEN)
96 return -EFAULT; /* match IRIX behaviour */
97
98 args->hashval = xfs_da_hashname(args->name, args->namelen);
99 return 0;
100 }
101
102 int
xfs_inode_hasattr(struct xfs_inode * ip)103 xfs_inode_hasattr(
104 struct xfs_inode *ip)
105 {
106 if (!XFS_IFORK_Q(ip) ||
107 (ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
108 ip->i_d.di_anextents == 0))
109 return 0;
110 return 1;
111 }
112
113 /*========================================================================
114 * Overall external interface routines.
115 *========================================================================*/
116
117 int
xfs_attr_get(struct xfs_inode * ip,const unsigned char * name,unsigned char * value,int * valuelenp,int flags)118 xfs_attr_get(
119 struct xfs_inode *ip,
120 const unsigned char *name,
121 unsigned char *value,
122 int *valuelenp,
123 int flags)
124 {
125 struct xfs_da_args args;
126 uint lock_mode;
127 int error;
128
129 XFS_STATS_INC(ip->i_mount, xs_attr_get);
130
131 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
132 return -EIO;
133
134 error = xfs_attr_args_init(&args, ip, name, flags);
135 if (error)
136 return error;
137
138 args.value = value;
139 args.valuelen = *valuelenp;
140 /* Entirely possible to look up a name which doesn't exist */
141 args.op_flags = XFS_DA_OP_OKNOENT;
142
143 lock_mode = xfs_ilock_attr_map_shared(ip);
144 if (!xfs_inode_hasattr(ip))
145 error = -ENOATTR;
146 else if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL)
147 error = xfs_attr_shortform_getvalue(&args);
148 else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK))
149 error = xfs_attr_leaf_get(&args);
150 else
151 error = xfs_attr_node_get(&args);
152 xfs_iunlock(ip, lock_mode);
153
154 *valuelenp = args.valuelen;
155 return error == -EEXIST ? 0 : error;
156 }
157
158 /*
159 * Calculate how many blocks we need for the new attribute,
160 */
161 STATIC int
xfs_attr_calc_size(struct xfs_da_args * args,int * local)162 xfs_attr_calc_size(
163 struct xfs_da_args *args,
164 int *local)
165 {
166 struct xfs_mount *mp = args->dp->i_mount;
167 int size;
168 int nblks;
169
170 /*
171 * Determine space new attribute will use, and if it would be
172 * "local" or "remote" (note: local != inline).
173 */
174 size = xfs_attr_leaf_newentsize(args, local);
175 nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
176 if (*local) {
177 if (size > (args->geo->blksize / 2)) {
178 /* Double split possible */
179 nblks *= 2;
180 }
181 } else {
182 /*
183 * Out of line attribute, cannot double split, but
184 * make room for the attribute value itself.
185 */
186 uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
187 nblks += dblocks;
188 nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
189 }
190
191 return nblks;
192 }
193
194 int
xfs_attr_set(struct xfs_inode * dp,const unsigned char * name,unsigned char * value,int valuelen,int flags)195 xfs_attr_set(
196 struct xfs_inode *dp,
197 const unsigned char *name,
198 unsigned char *value,
199 int valuelen,
200 int flags)
201 {
202 struct xfs_mount *mp = dp->i_mount;
203 struct xfs_da_args args;
204 struct xfs_defer_ops dfops;
205 struct xfs_trans_res tres;
206 xfs_fsblock_t firstblock;
207 int rsvd = (flags & ATTR_ROOT) != 0;
208 int error, err2, local;
209
210 XFS_STATS_INC(mp, xs_attr_set);
211
212 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
213 return -EIO;
214
215 error = xfs_attr_args_init(&args, dp, name, flags);
216 if (error)
217 return error;
218
219 args.value = value;
220 args.valuelen = valuelen;
221 args.firstblock = &firstblock;
222 args.dfops = &dfops;
223 args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
224 args.total = xfs_attr_calc_size(&args, &local);
225
226 error = xfs_qm_dqattach(dp, 0);
227 if (error)
228 return error;
229
230 /*
231 * If the inode doesn't have an attribute fork, add one.
232 * (inode must not be locked when we call this routine)
233 */
234 if (XFS_IFORK_Q(dp) == 0) {
235 int sf_size = sizeof(xfs_attr_sf_hdr_t) +
236 XFS_ATTR_SF_ENTSIZE_BYNAME(args.namelen, valuelen);
237
238 error = xfs_bmap_add_attrfork(dp, sf_size, rsvd);
239 if (error)
240 return error;
241 }
242
243 tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
244 M_RES(mp)->tr_attrsetrt.tr_logres * args.total;
245 tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
246 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
247
248 /*
249 * Root fork attributes can use reserved data blocks for this
250 * operation if necessary
251 */
252 error = xfs_trans_alloc(mp, &tres, args.total, 0,
253 rsvd ? XFS_TRANS_RESERVE : 0, &args.trans);
254 if (error)
255 return error;
256
257 xfs_ilock(dp, XFS_ILOCK_EXCL);
258 error = xfs_trans_reserve_quota_nblks(args.trans, dp, args.total, 0,
259 rsvd ? XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
260 XFS_QMOPT_RES_REGBLKS);
261 if (error) {
262 xfs_iunlock(dp, XFS_ILOCK_EXCL);
263 xfs_trans_cancel(args.trans);
264 return error;
265 }
266
267 xfs_trans_ijoin(args.trans, dp, 0);
268
269 /*
270 * If the attribute list is non-existent or a shortform list,
271 * upgrade it to a single-leaf-block attribute list.
272 */
273 if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
274 (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
275 dp->i_d.di_anextents == 0)) {
276
277 /*
278 * Build initial attribute list (if required).
279 */
280 if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS)
281 xfs_attr_shortform_create(&args);
282
283 /*
284 * Try to add the attr to the attribute list in
285 * the inode.
286 */
287 error = xfs_attr_shortform_addname(&args);
288 if (error != -ENOSPC) {
289 /*
290 * Commit the shortform mods, and we're done.
291 * NOTE: this is also the error path (EEXIST, etc).
292 */
293 ASSERT(args.trans != NULL);
294
295 /*
296 * If this is a synchronous mount, make sure that
297 * the transaction goes to disk before returning
298 * to the user.
299 */
300 if (mp->m_flags & XFS_MOUNT_WSYNC)
301 xfs_trans_set_sync(args.trans);
302
303 if (!error && (flags & ATTR_KERNOTIME) == 0) {
304 xfs_trans_ichgtime(args.trans, dp,
305 XFS_ICHGTIME_CHG);
306 }
307 err2 = xfs_trans_commit(args.trans);
308 xfs_iunlock(dp, XFS_ILOCK_EXCL);
309
310 return error ? error : err2;
311 }
312
313 /*
314 * It won't fit in the shortform, transform to a leaf block.
315 * GROT: another possible req'mt for a double-split btree op.
316 */
317 xfs_defer_init(args.dfops, args.firstblock);
318 error = xfs_attr_shortform_to_leaf(&args);
319 if (!error)
320 error = xfs_defer_finish(&args.trans, args.dfops, dp);
321 if (error) {
322 args.trans = NULL;
323 xfs_defer_cancel(&dfops);
324 goto out;
325 }
326
327 /*
328 * Commit the leaf transformation. We'll need another (linked)
329 * transaction to add the new attribute to the leaf.
330 */
331
332 error = xfs_trans_roll(&args.trans, dp);
333 if (error)
334 goto out;
335
336 }
337
338 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
339 error = xfs_attr_leaf_addname(&args);
340 else
341 error = xfs_attr_node_addname(&args);
342 if (error)
343 goto out;
344
345 /*
346 * If this is a synchronous mount, make sure that the
347 * transaction goes to disk before returning to the user.
348 */
349 if (mp->m_flags & XFS_MOUNT_WSYNC)
350 xfs_trans_set_sync(args.trans);
351
352 if ((flags & ATTR_KERNOTIME) == 0)
353 xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
354
355 /*
356 * Commit the last in the sequence of transactions.
357 */
358 xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
359 error = xfs_trans_commit(args.trans);
360 xfs_iunlock(dp, XFS_ILOCK_EXCL);
361
362 return error;
363
364 out:
365 if (args.trans)
366 xfs_trans_cancel(args.trans);
367 xfs_iunlock(dp, XFS_ILOCK_EXCL);
368 return error;
369 }
370
371 /*
372 * Generic handler routine to remove a name from an attribute list.
373 * Transitions attribute list from Btree to shortform as necessary.
374 */
375 int
xfs_attr_remove(struct xfs_inode * dp,const unsigned char * name,int flags)376 xfs_attr_remove(
377 struct xfs_inode *dp,
378 const unsigned char *name,
379 int flags)
380 {
381 struct xfs_mount *mp = dp->i_mount;
382 struct xfs_da_args args;
383 struct xfs_defer_ops dfops;
384 xfs_fsblock_t firstblock;
385 int error;
386
387 XFS_STATS_INC(mp, xs_attr_remove);
388
389 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
390 return -EIO;
391
392 error = xfs_attr_args_init(&args, dp, name, flags);
393 if (error)
394 return error;
395
396 args.firstblock = &firstblock;
397 args.dfops = &dfops;
398
399 /*
400 * we have no control over the attribute names that userspace passes us
401 * to remove, so we have to allow the name lookup prior to attribute
402 * removal to fail.
403 */
404 args.op_flags = XFS_DA_OP_OKNOENT;
405
406 error = xfs_qm_dqattach(dp, 0);
407 if (error)
408 return error;
409
410 /*
411 * Root fork attributes can use reserved data blocks for this
412 * operation if necessary
413 */
414 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrrm,
415 XFS_ATTRRM_SPACE_RES(mp), 0,
416 (flags & ATTR_ROOT) ? XFS_TRANS_RESERVE : 0,
417 &args.trans);
418 if (error)
419 return error;
420
421 xfs_ilock(dp, XFS_ILOCK_EXCL);
422 /*
423 * No need to make quota reservations here. We expect to release some
424 * blocks not allocate in the common case.
425 */
426 xfs_trans_ijoin(args.trans, dp, 0);
427
428 if (!xfs_inode_hasattr(dp)) {
429 error = -ENOATTR;
430 } else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
431 ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
432 error = xfs_attr_shortform_remove(&args);
433 } else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
434 error = xfs_attr_leaf_removename(&args);
435 } else {
436 error = xfs_attr_node_removename(&args);
437 }
438
439 if (error)
440 goto out;
441
442 /*
443 * If this is a synchronous mount, make sure that the
444 * transaction goes to disk before returning to the user.
445 */
446 if (mp->m_flags & XFS_MOUNT_WSYNC)
447 xfs_trans_set_sync(args.trans);
448
449 if ((flags & ATTR_KERNOTIME) == 0)
450 xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
451
452 /*
453 * Commit the last in the sequence of transactions.
454 */
455 xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
456 error = xfs_trans_commit(args.trans);
457 xfs_iunlock(dp, XFS_ILOCK_EXCL);
458
459 return error;
460
461 out:
462 if (args.trans)
463 xfs_trans_cancel(args.trans);
464 xfs_iunlock(dp, XFS_ILOCK_EXCL);
465 return error;
466 }
467
468 /*========================================================================
469 * External routines when attribute list is inside the inode
470 *========================================================================*/
471
472 /*
473 * Add a name to the shortform attribute list structure
474 * This is the external routine.
475 */
476 STATIC int
xfs_attr_shortform_addname(xfs_da_args_t * args)477 xfs_attr_shortform_addname(xfs_da_args_t *args)
478 {
479 int newsize, forkoff, retval;
480
481 trace_xfs_attr_sf_addname(args);
482
483 retval = xfs_attr_shortform_lookup(args);
484 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
485 return retval;
486 } else if (retval == -EEXIST) {
487 if (args->flags & ATTR_CREATE)
488 return retval;
489 retval = xfs_attr_shortform_remove(args);
490 ASSERT(retval == 0);
491 }
492
493 if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
494 args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
495 return -ENOSPC;
496
497 newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
498 newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
499
500 forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
501 if (!forkoff)
502 return -ENOSPC;
503
504 xfs_attr_shortform_add(args, forkoff);
505 return 0;
506 }
507
508
509 /*========================================================================
510 * External routines when attribute list is one block
511 *========================================================================*/
512
513 /*
514 * Add a name to the leaf attribute list structure
515 *
516 * This leaf block cannot have a "remote" value, we only call this routine
517 * if bmap_one_block() says there is only one block (ie: no remote blks).
518 */
519 STATIC int
xfs_attr_leaf_addname(xfs_da_args_t * args)520 xfs_attr_leaf_addname(xfs_da_args_t *args)
521 {
522 xfs_inode_t *dp;
523 struct xfs_buf *bp;
524 int retval, error, forkoff;
525
526 trace_xfs_attr_leaf_addname(args);
527
528 /*
529 * Read the (only) block in the attribute list in.
530 */
531 dp = args->dp;
532 args->blkno = 0;
533 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
534 if (error)
535 return error;
536
537 /*
538 * Look up the given attribute in the leaf block. Figure out if
539 * the given flags produce an error or call for an atomic rename.
540 */
541 retval = xfs_attr3_leaf_lookup_int(bp, args);
542 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
543 xfs_trans_brelse(args->trans, bp);
544 return retval;
545 } else if (retval == -EEXIST) {
546 if (args->flags & ATTR_CREATE) { /* pure create op */
547 xfs_trans_brelse(args->trans, bp);
548 return retval;
549 }
550
551 trace_xfs_attr_leaf_replace(args);
552
553 /* save the attribute state for later removal*/
554 args->op_flags |= XFS_DA_OP_RENAME; /* an atomic rename */
555 args->blkno2 = args->blkno; /* set 2nd entry info*/
556 args->index2 = args->index;
557 args->rmtblkno2 = args->rmtblkno;
558 args->rmtblkcnt2 = args->rmtblkcnt;
559 args->rmtvaluelen2 = args->rmtvaluelen;
560
561 /*
562 * clear the remote attr state now that it is saved so that the
563 * values reflect the state of the attribute we are about to
564 * add, not the attribute we just found and will remove later.
565 */
566 args->rmtblkno = 0;
567 args->rmtblkcnt = 0;
568 args->rmtvaluelen = 0;
569 }
570
571 /*
572 * Add the attribute to the leaf block, transitioning to a Btree
573 * if required.
574 */
575 retval = xfs_attr3_leaf_add(bp, args);
576 if (retval == -ENOSPC) {
577 /*
578 * Promote the attribute list to the Btree format, then
579 * Commit that transaction so that the node_addname() call
580 * can manage its own transactions.
581 */
582 xfs_defer_init(args->dfops, args->firstblock);
583 error = xfs_attr3_leaf_to_node(args);
584 if (!error)
585 error = xfs_defer_finish(&args->trans, args->dfops, dp);
586 if (error) {
587 args->trans = NULL;
588 xfs_defer_cancel(args->dfops);
589 return error;
590 }
591
592 /*
593 * Commit the current trans (including the inode) and start
594 * a new one.
595 */
596 error = xfs_trans_roll(&args->trans, dp);
597 if (error)
598 return error;
599
600 /*
601 * Fob the whole rest of the problem off on the Btree code.
602 */
603 error = xfs_attr_node_addname(args);
604 return error;
605 }
606
607 /*
608 * Commit the transaction that added the attr name so that
609 * later routines can manage their own transactions.
610 */
611 error = xfs_trans_roll(&args->trans, dp);
612 if (error)
613 return error;
614
615 /*
616 * If there was an out-of-line value, allocate the blocks we
617 * identified for its storage and copy the value. This is done
618 * after we create the attribute so that we don't overflow the
619 * maximum size of a transaction and/or hit a deadlock.
620 */
621 if (args->rmtblkno > 0) {
622 error = xfs_attr_rmtval_set(args);
623 if (error)
624 return error;
625 }
626
627 /*
628 * If this is an atomic rename operation, we must "flip" the
629 * incomplete flags on the "new" and "old" attribute/value pairs
630 * so that one disappears and one appears atomically. Then we
631 * must remove the "old" attribute/value pair.
632 */
633 if (args->op_flags & XFS_DA_OP_RENAME) {
634 /*
635 * In a separate transaction, set the incomplete flag on the
636 * "old" attr and clear the incomplete flag on the "new" attr.
637 */
638 error = xfs_attr3_leaf_flipflags(args);
639 if (error)
640 return error;
641
642 /*
643 * Dismantle the "old" attribute/value pair by removing
644 * a "remote" value (if it exists).
645 */
646 args->index = args->index2;
647 args->blkno = args->blkno2;
648 args->rmtblkno = args->rmtblkno2;
649 args->rmtblkcnt = args->rmtblkcnt2;
650 args->rmtvaluelen = args->rmtvaluelen2;
651 if (args->rmtblkno) {
652 error = xfs_attr_rmtval_remove(args);
653 if (error)
654 return error;
655 }
656
657 /*
658 * Read in the block containing the "old" attr, then
659 * remove the "old" attr from that block (neat, huh!)
660 */
661 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
662 -1, &bp);
663 if (error)
664 return error;
665
666 xfs_attr3_leaf_remove(bp, args);
667
668 /*
669 * If the result is small enough, shrink it all into the inode.
670 */
671 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
672 xfs_defer_init(args->dfops, args->firstblock);
673 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
674 /* bp is gone due to xfs_da_shrink_inode */
675 if (!error)
676 error = xfs_defer_finish(&args->trans,
677 args->dfops, dp);
678 if (error) {
679 args->trans = NULL;
680 xfs_defer_cancel(args->dfops);
681 return error;
682 }
683 }
684
685 /*
686 * Commit the remove and start the next trans in series.
687 */
688 error = xfs_trans_roll(&args->trans, dp);
689
690 } else if (args->rmtblkno > 0) {
691 /*
692 * Added a "remote" value, just clear the incomplete flag.
693 */
694 error = xfs_attr3_leaf_clearflag(args);
695 }
696 return error;
697 }
698
699 /*
700 * Remove a name from the leaf attribute list structure
701 *
702 * This leaf block cannot have a "remote" value, we only call this routine
703 * if bmap_one_block() says there is only one block (ie: no remote blks).
704 */
705 STATIC int
xfs_attr_leaf_removename(xfs_da_args_t * args)706 xfs_attr_leaf_removename(xfs_da_args_t *args)
707 {
708 xfs_inode_t *dp;
709 struct xfs_buf *bp;
710 int error, forkoff;
711
712 trace_xfs_attr_leaf_removename(args);
713
714 /*
715 * Remove the attribute.
716 */
717 dp = args->dp;
718 args->blkno = 0;
719 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
720 if (error)
721 return error;
722
723 error = xfs_attr3_leaf_lookup_int(bp, args);
724 if (error == -ENOATTR) {
725 xfs_trans_brelse(args->trans, bp);
726 return error;
727 }
728
729 xfs_attr3_leaf_remove(bp, args);
730
731 /*
732 * If the result is small enough, shrink it all into the inode.
733 */
734 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
735 xfs_defer_init(args->dfops, args->firstblock);
736 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
737 /* bp is gone due to xfs_da_shrink_inode */
738 if (!error)
739 error = xfs_defer_finish(&args->trans, args->dfops, dp);
740 if (error) {
741 args->trans = NULL;
742 xfs_defer_cancel(args->dfops);
743 return error;
744 }
745 }
746 return 0;
747 }
748
749 /*
750 * Look up a name in a leaf attribute list structure.
751 *
752 * This leaf block cannot have a "remote" value, we only call this routine
753 * if bmap_one_block() says there is only one block (ie: no remote blks).
754 */
755 STATIC int
xfs_attr_leaf_get(xfs_da_args_t * args)756 xfs_attr_leaf_get(xfs_da_args_t *args)
757 {
758 struct xfs_buf *bp;
759 int error;
760
761 trace_xfs_attr_leaf_get(args);
762
763 args->blkno = 0;
764 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
765 if (error)
766 return error;
767
768 error = xfs_attr3_leaf_lookup_int(bp, args);
769 if (error != -EEXIST) {
770 xfs_trans_brelse(args->trans, bp);
771 return error;
772 }
773 error = xfs_attr3_leaf_getvalue(bp, args);
774 xfs_trans_brelse(args->trans, bp);
775 if (!error && (args->rmtblkno > 0) && !(args->flags & ATTR_KERNOVAL)) {
776 error = xfs_attr_rmtval_get(args);
777 }
778 return error;
779 }
780
781 /*========================================================================
782 * External routines when attribute list size > geo->blksize
783 *========================================================================*/
784
785 /*
786 * Add a name to a Btree-format attribute list.
787 *
788 * This will involve walking down the Btree, and may involve splitting
789 * leaf nodes and even splitting intermediate nodes up to and including
790 * the root node (a special case of an intermediate node).
791 *
792 * "Remote" attribute values confuse the issue and atomic rename operations
793 * add a whole extra layer of confusion on top of that.
794 */
795 STATIC int
xfs_attr_node_addname(xfs_da_args_t * args)796 xfs_attr_node_addname(xfs_da_args_t *args)
797 {
798 xfs_da_state_t *state;
799 xfs_da_state_blk_t *blk;
800 xfs_inode_t *dp;
801 xfs_mount_t *mp;
802 int retval, error;
803
804 trace_xfs_attr_node_addname(args);
805
806 /*
807 * Fill in bucket of arguments/results/context to carry around.
808 */
809 dp = args->dp;
810 mp = dp->i_mount;
811 restart:
812 state = xfs_da_state_alloc();
813 state->args = args;
814 state->mp = mp;
815
816 /*
817 * Search to see if name already exists, and get back a pointer
818 * to where it should go.
819 */
820 error = xfs_da3_node_lookup_int(state, &retval);
821 if (error)
822 goto out;
823 blk = &state->path.blk[ state->path.active-1 ];
824 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
825 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
826 goto out;
827 } else if (retval == -EEXIST) {
828 if (args->flags & ATTR_CREATE)
829 goto out;
830
831 trace_xfs_attr_node_replace(args);
832
833 /* save the attribute state for later removal*/
834 args->op_flags |= XFS_DA_OP_RENAME; /* atomic rename op */
835 args->blkno2 = args->blkno; /* set 2nd entry info*/
836 args->index2 = args->index;
837 args->rmtblkno2 = args->rmtblkno;
838 args->rmtblkcnt2 = args->rmtblkcnt;
839 args->rmtvaluelen2 = args->rmtvaluelen;
840
841 /*
842 * clear the remote attr state now that it is saved so that the
843 * values reflect the state of the attribute we are about to
844 * add, not the attribute we just found and will remove later.
845 */
846 args->rmtblkno = 0;
847 args->rmtblkcnt = 0;
848 args->rmtvaluelen = 0;
849 }
850
851 retval = xfs_attr3_leaf_add(blk->bp, state->args);
852 if (retval == -ENOSPC) {
853 if (state->path.active == 1) {
854 /*
855 * Its really a single leaf node, but it had
856 * out-of-line values so it looked like it *might*
857 * have been a b-tree.
858 */
859 xfs_da_state_free(state);
860 state = NULL;
861 xfs_defer_init(args->dfops, args->firstblock);
862 error = xfs_attr3_leaf_to_node(args);
863 if (!error)
864 error = xfs_defer_finish(&args->trans,
865 args->dfops, dp);
866 if (error) {
867 args->trans = NULL;
868 xfs_defer_cancel(args->dfops);
869 goto out;
870 }
871
872 /*
873 * Commit the node conversion and start the next
874 * trans in the chain.
875 */
876 error = xfs_trans_roll(&args->trans, dp);
877 if (error)
878 goto out;
879
880 goto restart;
881 }
882
883 /*
884 * Split as many Btree elements as required.
885 * This code tracks the new and old attr's location
886 * in the index/blkno/rmtblkno/rmtblkcnt fields and
887 * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
888 */
889 xfs_defer_init(args->dfops, args->firstblock);
890 error = xfs_da3_split(state);
891 if (!error)
892 error = xfs_defer_finish(&args->trans, args->dfops, dp);
893 if (error) {
894 args->trans = NULL;
895 xfs_defer_cancel(args->dfops);
896 goto out;
897 }
898 } else {
899 /*
900 * Addition succeeded, update Btree hashvals.
901 */
902 xfs_da3_fixhashpath(state, &state->path);
903 }
904
905 /*
906 * Kill the state structure, we're done with it and need to
907 * allow the buffers to come back later.
908 */
909 xfs_da_state_free(state);
910 state = NULL;
911
912 /*
913 * Commit the leaf addition or btree split and start the next
914 * trans in the chain.
915 */
916 error = xfs_trans_roll(&args->trans, dp);
917 if (error)
918 goto out;
919
920 /*
921 * If there was an out-of-line value, allocate the blocks we
922 * identified for its storage and copy the value. This is done
923 * after we create the attribute so that we don't overflow the
924 * maximum size of a transaction and/or hit a deadlock.
925 */
926 if (args->rmtblkno > 0) {
927 error = xfs_attr_rmtval_set(args);
928 if (error)
929 return error;
930 }
931
932 /*
933 * If this is an atomic rename operation, we must "flip" the
934 * incomplete flags on the "new" and "old" attribute/value pairs
935 * so that one disappears and one appears atomically. Then we
936 * must remove the "old" attribute/value pair.
937 */
938 if (args->op_flags & XFS_DA_OP_RENAME) {
939 /*
940 * In a separate transaction, set the incomplete flag on the
941 * "old" attr and clear the incomplete flag on the "new" attr.
942 */
943 error = xfs_attr3_leaf_flipflags(args);
944 if (error)
945 goto out;
946
947 /*
948 * Dismantle the "old" attribute/value pair by removing
949 * a "remote" value (if it exists).
950 */
951 args->index = args->index2;
952 args->blkno = args->blkno2;
953 args->rmtblkno = args->rmtblkno2;
954 args->rmtblkcnt = args->rmtblkcnt2;
955 args->rmtvaluelen = args->rmtvaluelen2;
956 if (args->rmtblkno) {
957 error = xfs_attr_rmtval_remove(args);
958 if (error)
959 return error;
960 }
961
962 /*
963 * Re-find the "old" attribute entry after any split ops.
964 * The INCOMPLETE flag means that we will find the "old"
965 * attr, not the "new" one.
966 */
967 args->flags |= XFS_ATTR_INCOMPLETE;
968 state = xfs_da_state_alloc();
969 state->args = args;
970 state->mp = mp;
971 state->inleaf = 0;
972 error = xfs_da3_node_lookup_int(state, &retval);
973 if (error)
974 goto out;
975
976 /*
977 * Remove the name and update the hashvals in the tree.
978 */
979 blk = &state->path.blk[ state->path.active-1 ];
980 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
981 error = xfs_attr3_leaf_remove(blk->bp, args);
982 xfs_da3_fixhashpath(state, &state->path);
983
984 /*
985 * Check to see if the tree needs to be collapsed.
986 */
987 if (retval && (state->path.active > 1)) {
988 xfs_defer_init(args->dfops, args->firstblock);
989 error = xfs_da3_join(state);
990 if (!error)
991 error = xfs_defer_finish(&args->trans,
992 args->dfops, dp);
993 if (error) {
994 args->trans = NULL;
995 xfs_defer_cancel(args->dfops);
996 goto out;
997 }
998 }
999
1000 /*
1001 * Commit and start the next trans in the chain.
1002 */
1003 error = xfs_trans_roll(&args->trans, dp);
1004 if (error)
1005 goto out;
1006
1007 } else if (args->rmtblkno > 0) {
1008 /*
1009 * Added a "remote" value, just clear the incomplete flag.
1010 */
1011 error = xfs_attr3_leaf_clearflag(args);
1012 if (error)
1013 goto out;
1014 }
1015 retval = error = 0;
1016
1017 out:
1018 if (state)
1019 xfs_da_state_free(state);
1020 if (error)
1021 return error;
1022 return retval;
1023 }
1024
1025 /*
1026 * Remove a name from a B-tree attribute list.
1027 *
1028 * This will involve walking down the Btree, and may involve joining
1029 * leaf nodes and even joining intermediate nodes up to and including
1030 * the root node (a special case of an intermediate node).
1031 */
1032 STATIC int
xfs_attr_node_removename(xfs_da_args_t * args)1033 xfs_attr_node_removename(xfs_da_args_t *args)
1034 {
1035 xfs_da_state_t *state;
1036 xfs_da_state_blk_t *blk;
1037 xfs_inode_t *dp;
1038 struct xfs_buf *bp;
1039 int retval, error, forkoff;
1040
1041 trace_xfs_attr_node_removename(args);
1042
1043 /*
1044 * Tie a string around our finger to remind us where we are.
1045 */
1046 dp = args->dp;
1047 state = xfs_da_state_alloc();
1048 state->args = args;
1049 state->mp = dp->i_mount;
1050
1051 /*
1052 * Search to see if name exists, and get back a pointer to it.
1053 */
1054 error = xfs_da3_node_lookup_int(state, &retval);
1055 if (error || (retval != -EEXIST)) {
1056 if (error == 0)
1057 error = retval;
1058 goto out;
1059 }
1060
1061 /*
1062 * If there is an out-of-line value, de-allocate the blocks.
1063 * This is done before we remove the attribute so that we don't
1064 * overflow the maximum size of a transaction and/or hit a deadlock.
1065 */
1066 blk = &state->path.blk[ state->path.active-1 ];
1067 ASSERT(blk->bp != NULL);
1068 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1069 if (args->rmtblkno > 0) {
1070 /*
1071 * Fill in disk block numbers in the state structure
1072 * so that we can get the buffers back after we commit
1073 * several transactions in the following calls.
1074 */
1075 error = xfs_attr_fillstate(state);
1076 if (error)
1077 goto out;
1078
1079 /*
1080 * Mark the attribute as INCOMPLETE, then bunmapi() the
1081 * remote value.
1082 */
1083 error = xfs_attr3_leaf_setflag(args);
1084 if (error)
1085 goto out;
1086 error = xfs_attr_rmtval_remove(args);
1087 if (error)
1088 goto out;
1089
1090 /*
1091 * Refill the state structure with buffers, the prior calls
1092 * released our buffers.
1093 */
1094 error = xfs_attr_refillstate(state);
1095 if (error)
1096 goto out;
1097 }
1098
1099 /*
1100 * Remove the name and update the hashvals in the tree.
1101 */
1102 blk = &state->path.blk[ state->path.active-1 ];
1103 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1104 retval = xfs_attr3_leaf_remove(blk->bp, args);
1105 xfs_da3_fixhashpath(state, &state->path);
1106
1107 /*
1108 * Check to see if the tree needs to be collapsed.
1109 */
1110 if (retval && (state->path.active > 1)) {
1111 xfs_defer_init(args->dfops, args->firstblock);
1112 error = xfs_da3_join(state);
1113 if (!error)
1114 error = xfs_defer_finish(&args->trans, args->dfops, dp);
1115 if (error) {
1116 args->trans = NULL;
1117 xfs_defer_cancel(args->dfops);
1118 goto out;
1119 }
1120 /*
1121 * Commit the Btree join operation and start a new trans.
1122 */
1123 error = xfs_trans_roll(&args->trans, dp);
1124 if (error)
1125 goto out;
1126 }
1127
1128 /*
1129 * If the result is small enough, push it all into the inode.
1130 */
1131 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
1132 /*
1133 * Have to get rid of the copy of this dabuf in the state.
1134 */
1135 ASSERT(state->path.active == 1);
1136 ASSERT(state->path.blk[0].bp);
1137 state->path.blk[0].bp = NULL;
1138
1139 error = xfs_attr3_leaf_read(args->trans, args->dp, 0, -1, &bp);
1140 if (error)
1141 goto out;
1142
1143 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
1144 xfs_defer_init(args->dfops, args->firstblock);
1145 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
1146 /* bp is gone due to xfs_da_shrink_inode */
1147 if (!error)
1148 error = xfs_defer_finish(&args->trans,
1149 args->dfops, dp);
1150 if (error) {
1151 args->trans = NULL;
1152 xfs_defer_cancel(args->dfops);
1153 goto out;
1154 }
1155 } else
1156 xfs_trans_brelse(args->trans, bp);
1157 }
1158 error = 0;
1159
1160 out:
1161 xfs_da_state_free(state);
1162 return error;
1163 }
1164
1165 /*
1166 * Fill in the disk block numbers in the state structure for the buffers
1167 * that are attached to the state structure.
1168 * This is done so that we can quickly reattach ourselves to those buffers
1169 * after some set of transaction commits have released these buffers.
1170 */
1171 STATIC int
xfs_attr_fillstate(xfs_da_state_t * state)1172 xfs_attr_fillstate(xfs_da_state_t *state)
1173 {
1174 xfs_da_state_path_t *path;
1175 xfs_da_state_blk_t *blk;
1176 int level;
1177
1178 trace_xfs_attr_fillstate(state->args);
1179
1180 /*
1181 * Roll down the "path" in the state structure, storing the on-disk
1182 * block number for those buffers in the "path".
1183 */
1184 path = &state->path;
1185 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1186 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1187 if (blk->bp) {
1188 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1189 blk->bp = NULL;
1190 } else {
1191 blk->disk_blkno = 0;
1192 }
1193 }
1194
1195 /*
1196 * Roll down the "altpath" in the state structure, storing the on-disk
1197 * block number for those buffers in the "altpath".
1198 */
1199 path = &state->altpath;
1200 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1201 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1202 if (blk->bp) {
1203 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1204 blk->bp = NULL;
1205 } else {
1206 blk->disk_blkno = 0;
1207 }
1208 }
1209
1210 return 0;
1211 }
1212
1213 /*
1214 * Reattach the buffers to the state structure based on the disk block
1215 * numbers stored in the state structure.
1216 * This is done after some set of transaction commits have released those
1217 * buffers from our grip.
1218 */
1219 STATIC int
xfs_attr_refillstate(xfs_da_state_t * state)1220 xfs_attr_refillstate(xfs_da_state_t *state)
1221 {
1222 xfs_da_state_path_t *path;
1223 xfs_da_state_blk_t *blk;
1224 int level, error;
1225
1226 trace_xfs_attr_refillstate(state->args);
1227
1228 /*
1229 * Roll down the "path" in the state structure, storing the on-disk
1230 * block number for those buffers in the "path".
1231 */
1232 path = &state->path;
1233 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1234 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1235 if (blk->disk_blkno) {
1236 error = xfs_da3_node_read(state->args->trans,
1237 state->args->dp,
1238 blk->blkno, blk->disk_blkno,
1239 &blk->bp, XFS_ATTR_FORK);
1240 if (error)
1241 return error;
1242 } else {
1243 blk->bp = NULL;
1244 }
1245 }
1246
1247 /*
1248 * Roll down the "altpath" in the state structure, storing the on-disk
1249 * block number for those buffers in the "altpath".
1250 */
1251 path = &state->altpath;
1252 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1253 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1254 if (blk->disk_blkno) {
1255 error = xfs_da3_node_read(state->args->trans,
1256 state->args->dp,
1257 blk->blkno, blk->disk_blkno,
1258 &blk->bp, XFS_ATTR_FORK);
1259 if (error)
1260 return error;
1261 } else {
1262 blk->bp = NULL;
1263 }
1264 }
1265
1266 return 0;
1267 }
1268
1269 /*
1270 * Look up a filename in a node attribute list.
1271 *
1272 * This routine gets called for any attribute fork that has more than one
1273 * block, ie: both true Btree attr lists and for single-leaf-blocks with
1274 * "remote" values taking up more blocks.
1275 */
1276 STATIC int
xfs_attr_node_get(xfs_da_args_t * args)1277 xfs_attr_node_get(xfs_da_args_t *args)
1278 {
1279 xfs_da_state_t *state;
1280 xfs_da_state_blk_t *blk;
1281 int error, retval;
1282 int i;
1283
1284 trace_xfs_attr_node_get(args);
1285
1286 state = xfs_da_state_alloc();
1287 state->args = args;
1288 state->mp = args->dp->i_mount;
1289
1290 /*
1291 * Search to see if name exists, and get back a pointer to it.
1292 */
1293 error = xfs_da3_node_lookup_int(state, &retval);
1294 if (error) {
1295 retval = error;
1296 } else if (retval == -EEXIST) {
1297 blk = &state->path.blk[ state->path.active-1 ];
1298 ASSERT(blk->bp != NULL);
1299 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1300
1301 /*
1302 * Get the value, local or "remote"
1303 */
1304 retval = xfs_attr3_leaf_getvalue(blk->bp, args);
1305 if (!retval && (args->rmtblkno > 0)
1306 && !(args->flags & ATTR_KERNOVAL)) {
1307 retval = xfs_attr_rmtval_get(args);
1308 }
1309 }
1310
1311 /*
1312 * If not in a transaction, we have to release all the buffers.
1313 */
1314 for (i = 0; i < state->path.active; i++) {
1315 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1316 state->path.blk[i].bp = NULL;
1317 }
1318
1319 xfs_da_state_free(state);
1320 return retval;
1321 }
1322