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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 */
58STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
59
60/*
61 * Internal routines when attribute list is one block.
62 */
63STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
64STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
65STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
66
67/*
68 * Internal routines when attribute list is more than one block.
69 */
70STATIC int xfs_attr_node_get(xfs_da_args_t *args);
71STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
72STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
73STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
74STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
75
76
77STATIC int
78xfs_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
102int
103xfs_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/* Retrieve an extended attribute and its value. Must have ilock. */
118int
119xfs_attr_get_ilocked(
120 struct xfs_inode *ip,
121 struct xfs_da_args *args)
122{
123 ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
124
125 if (!xfs_inode_hasattr(ip))
126 return -ENOATTR;
127 else if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL)
128 return xfs_attr_shortform_getvalue(args);
129 else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK))
130 return xfs_attr_leaf_get(args);
131 else
132 return xfs_attr_node_get(args);
133}
134
135/* Retrieve an extended attribute by name, and its value. */
136int
137xfs_attr_get(
138 struct xfs_inode *ip,
139 const unsigned char *name,
140 unsigned char *value,
141 int *valuelenp,
142 int flags)
143{
144 struct xfs_da_args args;
145 uint lock_mode;
146 int error;
147
148 XFS_STATS_INC(ip->i_mount, xs_attr_get);
149
150 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
151 return -EIO;
152
153 error = xfs_attr_args_init(&args, ip, name, flags);
154 if (error)
155 return error;
156
157 args.value = value;
158 args.valuelen = *valuelenp;
159 /* Entirely possible to look up a name which doesn't exist */
160 args.op_flags = XFS_DA_OP_OKNOENT;
161
162 lock_mode = xfs_ilock_attr_map_shared(ip);
163 error = xfs_attr_get_ilocked(ip, &args);
164 xfs_iunlock(ip, lock_mode);
165
166 *valuelenp = args.valuelen;
167 return error == -EEXIST ? 0 : error;
168}
169
170/*
171 * Calculate how many blocks we need for the new attribute,
172 */
173STATIC int
174xfs_attr_calc_size(
175 struct xfs_da_args *args,
176 int *local)
177{
178 struct xfs_mount *mp = args->dp->i_mount;
179 int size;
180 int nblks;
181
182 /*
183 * Determine space new attribute will use, and if it would be
184 * "local" or "remote" (note: local != inline).
185 */
186 size = xfs_attr_leaf_newentsize(args, local);
187 nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
188 if (*local) {
189 if (size > (args->geo->blksize / 2)) {
190 /* Double split possible */
191 nblks *= 2;
192 }
193 } else {
194 /*
195 * Out of line attribute, cannot double split, but
196 * make room for the attribute value itself.
197 */
198 uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
199 nblks += dblocks;
200 nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
201 }
202
203 return nblks;
204}
205
206int
207xfs_attr_set(
208 struct xfs_inode *dp,
209 const unsigned char *name,
210 unsigned char *value,
211 int valuelen,
212 int flags)
213{
214 struct xfs_mount *mp = dp->i_mount;
215 struct xfs_buf *leaf_bp = NULL;
216 struct xfs_da_args args;
217 struct xfs_defer_ops dfops;
218 struct xfs_trans_res tres;
219 xfs_fsblock_t firstblock;
220 int rsvd = (flags & ATTR_ROOT) != 0;
221 int error, err2, local;
222
223 XFS_STATS_INC(mp, xs_attr_set);
224
225 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
226 return -EIO;
227
228 error = xfs_attr_args_init(&args, dp, name, flags);
229 if (error)
230 return error;
231
232 args.value = value;
233 args.valuelen = valuelen;
234 args.firstblock = &firstblock;
235 args.dfops = &dfops;
236 args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
237 args.total = xfs_attr_calc_size(&args, &local);
238
239 error = xfs_qm_dqattach(dp, 0);
240 if (error)
241 return error;
242
243 /*
244 * If the inode doesn't have an attribute fork, add one.
245 * (inode must not be locked when we call this routine)
246 */
247 if (XFS_IFORK_Q(dp) == 0) {
248 int sf_size = sizeof(xfs_attr_sf_hdr_t) +
249 XFS_ATTR_SF_ENTSIZE_BYNAME(args.namelen, valuelen);
250
251 error = xfs_bmap_add_attrfork(dp, sf_size, rsvd);
252 if (error)
253 return error;
254 }
255
256 tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
257 M_RES(mp)->tr_attrsetrt.tr_logres * args.total;
258 tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
259 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
260
261 /*
262 * Root fork attributes can use reserved data blocks for this
263 * operation if necessary
264 */
265 error = xfs_trans_alloc(mp, &tres, args.total, 0,
266 rsvd ? XFS_TRANS_RESERVE : 0, &args.trans);
267 if (error)
268 return error;
269
270 xfs_ilock(dp, XFS_ILOCK_EXCL);
271 error = xfs_trans_reserve_quota_nblks(args.trans, dp, args.total, 0,
272 rsvd ? XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
273 XFS_QMOPT_RES_REGBLKS);
274 if (error) {
275 xfs_iunlock(dp, XFS_ILOCK_EXCL);
276 xfs_trans_cancel(args.trans);
277 return error;
278 }
279
280 xfs_trans_ijoin(args.trans, dp, 0);
281
282 /*
283 * If the attribute list is non-existent or a shortform list,
284 * upgrade it to a single-leaf-block attribute list.
285 */
286 if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
287 (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
288 dp->i_d.di_anextents == 0)) {
289
290 /*
291 * Build initial attribute list (if required).
292 */
293 if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS)
294 xfs_attr_shortform_create(&args);
295
296 /*
297 * Try to add the attr to the attribute list in
298 * the inode.
299 */
300 error = xfs_attr_shortform_addname(&args);
301 if (error != -ENOSPC) {
302 /*
303 * Commit the shortform mods, and we're done.
304 * NOTE: this is also the error path (EEXIST, etc).
305 */
306 ASSERT(args.trans != NULL);
307
308 /*
309 * If this is a synchronous mount, make sure that
310 * the transaction goes to disk before returning
311 * to the user.
312 */
313 if (mp->m_flags & XFS_MOUNT_WSYNC)
314 xfs_trans_set_sync(args.trans);
315
316 if (!error && (flags & ATTR_KERNOTIME) == 0) {
317 xfs_trans_ichgtime(args.trans, dp,
318 XFS_ICHGTIME_CHG);
319 }
320 err2 = xfs_trans_commit(args.trans);
321 xfs_iunlock(dp, XFS_ILOCK_EXCL);
322
323 return error ? error : err2;
324 }
325
326 /*
327 * It won't fit in the shortform, transform to a leaf block.
328 * GROT: another possible req'mt for a double-split btree op.
329 */
330 xfs_defer_init(args.dfops, args.firstblock);
331 error = xfs_attr_shortform_to_leaf(&args, &leaf_bp);
332 if (error)
333 goto out_defer_cancel;
334 /*
335 * Prevent the leaf buffer from being unlocked so that a
336 * concurrent AIL push cannot grab the half-baked leaf
337 * buffer and run into problems with the write verifier.
338 */
339 xfs_trans_bhold(args.trans, leaf_bp);
340 xfs_defer_bjoin(args.dfops, leaf_bp);
341 xfs_defer_ijoin(args.dfops, dp);
342 error = xfs_defer_finish(&args.trans, args.dfops);
343 if (error)
344 goto out_defer_cancel;
345
346 /*
347 * Commit the leaf transformation. We'll need another (linked)
348 * transaction to add the new attribute to the leaf, which
349 * means that we have to hold & join the leaf buffer here too.
350 */
351 error = xfs_trans_roll_inode(&args.trans, dp);
352 if (error)
353 goto out;
354 xfs_trans_bjoin(args.trans, leaf_bp);
355 leaf_bp = NULL;
356 }
357
358 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
359 error = xfs_attr_leaf_addname(&args);
360 else
361 error = xfs_attr_node_addname(&args);
362 if (error)
363 goto out;
364
365 /*
366 * If this is a synchronous mount, make sure that the
367 * transaction goes to disk before returning to the user.
368 */
369 if (mp->m_flags & XFS_MOUNT_WSYNC)
370 xfs_trans_set_sync(args.trans);
371
372 if ((flags & ATTR_KERNOTIME) == 0)
373 xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
374
375 /*
376 * Commit the last in the sequence of transactions.
377 */
378 xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
379 error = xfs_trans_commit(args.trans);
380 xfs_iunlock(dp, XFS_ILOCK_EXCL);
381
382 return error;
383
384out_defer_cancel:
385 xfs_defer_cancel(&dfops);
386out:
387 if (leaf_bp)
388 xfs_trans_brelse(args.trans, leaf_bp);
389 if (args.trans)
390 xfs_trans_cancel(args.trans);
391 xfs_iunlock(dp, XFS_ILOCK_EXCL);
392 return error;
393}
394
395/*
396 * Generic handler routine to remove a name from an attribute list.
397 * Transitions attribute list from Btree to shortform as necessary.
398 */
399int
400xfs_attr_remove(
401 struct xfs_inode *dp,
402 const unsigned char *name,
403 int flags)
404{
405 struct xfs_mount *mp = dp->i_mount;
406 struct xfs_da_args args;
407 struct xfs_defer_ops dfops;
408 xfs_fsblock_t firstblock;
409 int error;
410
411 XFS_STATS_INC(mp, xs_attr_remove);
412
413 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
414 return -EIO;
415
416 error = xfs_attr_args_init(&args, dp, name, flags);
417 if (error)
418 return error;
419
420 args.firstblock = &firstblock;
421 args.dfops = &dfops;
422
423 /*
424 * we have no control over the attribute names that userspace passes us
425 * to remove, so we have to allow the name lookup prior to attribute
426 * removal to fail.
427 */
428 args.op_flags = XFS_DA_OP_OKNOENT;
429
430 error = xfs_qm_dqattach(dp, 0);
431 if (error)
432 return error;
433
434 /*
435 * Root fork attributes can use reserved data blocks for this
436 * operation if necessary
437 */
438 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrrm,
439 XFS_ATTRRM_SPACE_RES(mp), 0,
440 (flags & ATTR_ROOT) ? XFS_TRANS_RESERVE : 0,
441 &args.trans);
442 if (error)
443 return error;
444
445 xfs_ilock(dp, XFS_ILOCK_EXCL);
446 /*
447 * No need to make quota reservations here. We expect to release some
448 * blocks not allocate in the common case.
449 */
450 xfs_trans_ijoin(args.trans, dp, 0);
451
452 if (!xfs_inode_hasattr(dp)) {
453 error = -ENOATTR;
454 } else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
455 ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
456 error = xfs_attr_shortform_remove(&args);
457 } else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
458 error = xfs_attr_leaf_removename(&args);
459 } else {
460 error = xfs_attr_node_removename(&args);
461 }
462
463 if (error)
464 goto out;
465
466 /*
467 * If this is a synchronous mount, make sure that the
468 * transaction goes to disk before returning to the user.
469 */
470 if (mp->m_flags & XFS_MOUNT_WSYNC)
471 xfs_trans_set_sync(args.trans);
472
473 if ((flags & ATTR_KERNOTIME) == 0)
474 xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
475
476 /*
477 * Commit the last in the sequence of transactions.
478 */
479 xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
480 error = xfs_trans_commit(args.trans);
481 xfs_iunlock(dp, XFS_ILOCK_EXCL);
482
483 return error;
484
485out:
486 if (args.trans)
487 xfs_trans_cancel(args.trans);
488 xfs_iunlock(dp, XFS_ILOCK_EXCL);
489 return error;
490}
491
492/*========================================================================
493 * External routines when attribute list is inside the inode
494 *========================================================================*/
495
496/*
497 * Add a name to the shortform attribute list structure
498 * This is the external routine.
499 */
500STATIC int
501xfs_attr_shortform_addname(xfs_da_args_t *args)
502{
503 int newsize, forkoff, retval;
504
505 trace_xfs_attr_sf_addname(args);
506
507 retval = xfs_attr_shortform_lookup(args);
508 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
509 return retval;
510 } else if (retval == -EEXIST) {
511 if (args->flags & ATTR_CREATE)
512 return retval;
513 retval = xfs_attr_shortform_remove(args);
514 if (retval)
515 return retval;
516 /*
517 * Since we have removed the old attr, clear ATTR_REPLACE so
518 * that the leaf format add routine won't trip over the attr
519 * not being around.
520 */
521 args->flags &= ~ATTR_REPLACE;
522 }
523
524 if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
525 args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
526 return -ENOSPC;
527
528 newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
529 newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
530
531 forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
532 if (!forkoff)
533 return -ENOSPC;
534
535 xfs_attr_shortform_add(args, forkoff);
536 return 0;
537}
538
539
540/*========================================================================
541 * External routines when attribute list is one block
542 *========================================================================*/
543
544/*
545 * Add a name to the leaf attribute list structure
546 *
547 * This leaf block cannot have a "remote" value, we only call this routine
548 * if bmap_one_block() says there is only one block (ie: no remote blks).
549 */
550STATIC int
551xfs_attr_leaf_addname(xfs_da_args_t *args)
552{
553 xfs_inode_t *dp;
554 struct xfs_buf *bp;
555 int retval, error, forkoff;
556
557 trace_xfs_attr_leaf_addname(args);
558
559 /*
560 * Read the (only) block in the attribute list in.
561 */
562 dp = args->dp;
563 args->blkno = 0;
564 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
565 if (error)
566 return error;
567
568 /*
569 * Look up the given attribute in the leaf block. Figure out if
570 * the given flags produce an error or call for an atomic rename.
571 */
572 retval = xfs_attr3_leaf_lookup_int(bp, args);
573 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
574 xfs_trans_brelse(args->trans, bp);
575 return retval;
576 } else if (retval == -EEXIST) {
577 if (args->flags & ATTR_CREATE) { /* pure create op */
578 xfs_trans_brelse(args->trans, bp);
579 return retval;
580 }
581
582 trace_xfs_attr_leaf_replace(args);
583
584 /* save the attribute state for later removal*/
585 args->op_flags |= XFS_DA_OP_RENAME; /* an atomic rename */
586 args->blkno2 = args->blkno; /* set 2nd entry info*/
587 args->index2 = args->index;
588 args->rmtblkno2 = args->rmtblkno;
589 args->rmtblkcnt2 = args->rmtblkcnt;
590 args->rmtvaluelen2 = args->rmtvaluelen;
591
592 /*
593 * clear the remote attr state now that it is saved so that the
594 * values reflect the state of the attribute we are about to
595 * add, not the attribute we just found and will remove later.
596 */
597 args->rmtblkno = 0;
598 args->rmtblkcnt = 0;
599 args->rmtvaluelen = 0;
600 }
601
602 /*
603 * Add the attribute to the leaf block, transitioning to a Btree
604 * if required.
605 */
606 retval = xfs_attr3_leaf_add(bp, args);
607 if (retval == -ENOSPC) {
608 /*
609 * Promote the attribute list to the Btree format, then
610 * Commit that transaction so that the node_addname() call
611 * can manage its own transactions.
612 */
613 xfs_defer_init(args->dfops, args->firstblock);
614 error = xfs_attr3_leaf_to_node(args);
615 if (error)
616 goto out_defer_cancel;
617 xfs_defer_ijoin(args->dfops, dp);
618 error = xfs_defer_finish(&args->trans, args->dfops);
619 if (error)
620 goto out_defer_cancel;
621
622 /*
623 * Commit the current trans (including the inode) and start
624 * a new one.
625 */
626 error = xfs_trans_roll_inode(&args->trans, dp);
627 if (error)
628 return error;
629
630 /*
631 * Fob the whole rest of the problem off on the Btree code.
632 */
633 error = xfs_attr_node_addname(args);
634 return error;
635 }
636
637 /*
638 * Commit the transaction that added the attr name so that
639 * later routines can manage their own transactions.
640 */
641 error = xfs_trans_roll_inode(&args->trans, dp);
642 if (error)
643 return error;
644
645 /*
646 * If there was an out-of-line value, allocate the blocks we
647 * identified for its storage and copy the value. This is done
648 * after we create the attribute so that we don't overflow the
649 * maximum size of a transaction and/or hit a deadlock.
650 */
651 if (args->rmtblkno > 0) {
652 error = xfs_attr_rmtval_set(args);
653 if (error)
654 return error;
655 }
656
657 /*
658 * If this is an atomic rename operation, we must "flip" the
659 * incomplete flags on the "new" and "old" attribute/value pairs
660 * so that one disappears and one appears atomically. Then we
661 * must remove the "old" attribute/value pair.
662 */
663 if (args->op_flags & XFS_DA_OP_RENAME) {
664 /*
665 * In a separate transaction, set the incomplete flag on the
666 * "old" attr and clear the incomplete flag on the "new" attr.
667 */
668 error = xfs_attr3_leaf_flipflags(args);
669 if (error)
670 return error;
671
672 /*
673 * Dismantle the "old" attribute/value pair by removing
674 * a "remote" value (if it exists).
675 */
676 args->index = args->index2;
677 args->blkno = args->blkno2;
678 args->rmtblkno = args->rmtblkno2;
679 args->rmtblkcnt = args->rmtblkcnt2;
680 args->rmtvaluelen = args->rmtvaluelen2;
681 if (args->rmtblkno) {
682 error = xfs_attr_rmtval_remove(args);
683 if (error)
684 return error;
685 }
686
687 /*
688 * Read in the block containing the "old" attr, then
689 * remove the "old" attr from that block (neat, huh!)
690 */
691 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
692 -1, &bp);
693 if (error)
694 return error;
695
696 xfs_attr3_leaf_remove(bp, args);
697
698 /*
699 * If the result is small enough, shrink it all into the inode.
700 */
701 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
702 xfs_defer_init(args->dfops, args->firstblock);
703 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
704 /* bp is gone due to xfs_da_shrink_inode */
705 if (error)
706 goto out_defer_cancel;
707 xfs_defer_ijoin(args->dfops, dp);
708 error = xfs_defer_finish(&args->trans, args->dfops);
709 if (error)
710 goto out_defer_cancel;
711 }
712
713 /*
714 * Commit the remove and start the next trans in series.
715 */
716 error = xfs_trans_roll_inode(&args->trans, dp);
717
718 } else if (args->rmtblkno > 0) {
719 /*
720 * Added a "remote" value, just clear the incomplete flag.
721 */
722 error = xfs_attr3_leaf_clearflag(args);
723 }
724 return error;
725out_defer_cancel:
726 xfs_defer_cancel(args->dfops);
727 return error;
728}
729
730/*
731 * Remove a name from the leaf attribute list structure
732 *
733 * This leaf block cannot have a "remote" value, we only call this routine
734 * if bmap_one_block() says there is only one block (ie: no remote blks).
735 */
736STATIC int
737xfs_attr_leaf_removename(xfs_da_args_t *args)
738{
739 xfs_inode_t *dp;
740 struct xfs_buf *bp;
741 int error, forkoff;
742
743 trace_xfs_attr_leaf_removename(args);
744
745 /*
746 * Remove the attribute.
747 */
748 dp = args->dp;
749 args->blkno = 0;
750 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
751 if (error)
752 return error;
753
754 error = xfs_attr3_leaf_lookup_int(bp, args);
755 if (error == -ENOATTR) {
756 xfs_trans_brelse(args->trans, bp);
757 return error;
758 }
759
760 xfs_attr3_leaf_remove(bp, args);
761
762 /*
763 * If the result is small enough, shrink it all into the inode.
764 */
765 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
766 xfs_defer_init(args->dfops, args->firstblock);
767 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
768 /* bp is gone due to xfs_da_shrink_inode */
769 if (error)
770 goto out_defer_cancel;
771 xfs_defer_ijoin(args->dfops, dp);
772 error = xfs_defer_finish(&args->trans, args->dfops);
773 if (error)
774 goto out_defer_cancel;
775 }
776 return 0;
777out_defer_cancel:
778 xfs_defer_cancel(args->dfops);
779 return error;
780}
781
782/*
783 * Look up a name in a leaf attribute list structure.
784 *
785 * This leaf block cannot have a "remote" value, we only call this routine
786 * if bmap_one_block() says there is only one block (ie: no remote blks).
787 */
788STATIC int
789xfs_attr_leaf_get(xfs_da_args_t *args)
790{
791 struct xfs_buf *bp;
792 int error;
793
794 trace_xfs_attr_leaf_get(args);
795
796 args->blkno = 0;
797 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
798 if (error)
799 return error;
800
801 error = xfs_attr3_leaf_lookup_int(bp, args);
802 if (error != -EEXIST) {
803 xfs_trans_brelse(args->trans, bp);
804 return error;
805 }
806 error = xfs_attr3_leaf_getvalue(bp, args);
807 xfs_trans_brelse(args->trans, bp);
808 if (!error && (args->rmtblkno > 0) && !(args->flags & ATTR_KERNOVAL)) {
809 error = xfs_attr_rmtval_get(args);
810 }
811 return error;
812}
813
814/*========================================================================
815 * External routines when attribute list size > geo->blksize
816 *========================================================================*/
817
818/*
819 * Add a name to a Btree-format attribute list.
820 *
821 * This will involve walking down the Btree, and may involve splitting
822 * leaf nodes and even splitting intermediate nodes up to and including
823 * the root node (a special case of an intermediate node).
824 *
825 * "Remote" attribute values confuse the issue and atomic rename operations
826 * add a whole extra layer of confusion on top of that.
827 */
828STATIC int
829xfs_attr_node_addname(xfs_da_args_t *args)
830{
831 xfs_da_state_t *state;
832 xfs_da_state_blk_t *blk;
833 xfs_inode_t *dp;
834 xfs_mount_t *mp;
835 int retval, error;
836
837 trace_xfs_attr_node_addname(args);
838
839 /*
840 * Fill in bucket of arguments/results/context to carry around.
841 */
842 dp = args->dp;
843 mp = dp->i_mount;
844restart:
845 state = xfs_da_state_alloc();
846 state->args = args;
847 state->mp = mp;
848
849 /*
850 * Search to see if name already exists, and get back a pointer
851 * to where it should go.
852 */
853 error = xfs_da3_node_lookup_int(state, &retval);
854 if (error)
855 goto out;
856 blk = &state->path.blk[ state->path.active-1 ];
857 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
858 if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
859 goto out;
860 } else if (retval == -EEXIST) {
861 if (args->flags & ATTR_CREATE)
862 goto out;
863
864 trace_xfs_attr_node_replace(args);
865
866 /* save the attribute state for later removal*/
867 args->op_flags |= XFS_DA_OP_RENAME; /* atomic rename op */
868 args->blkno2 = args->blkno; /* set 2nd entry info*/
869 args->index2 = args->index;
870 args->rmtblkno2 = args->rmtblkno;
871 args->rmtblkcnt2 = args->rmtblkcnt;
872 args->rmtvaluelen2 = args->rmtvaluelen;
873
874 /*
875 * clear the remote attr state now that it is saved so that the
876 * values reflect the state of the attribute we are about to
877 * add, not the attribute we just found and will remove later.
878 */
879 args->rmtblkno = 0;
880 args->rmtblkcnt = 0;
881 args->rmtvaluelen = 0;
882 }
883
884 retval = xfs_attr3_leaf_add(blk->bp, state->args);
885 if (retval == -ENOSPC) {
886 if (state->path.active == 1) {
887 /*
888 * Its really a single leaf node, but it had
889 * out-of-line values so it looked like it *might*
890 * have been a b-tree.
891 */
892 xfs_da_state_free(state);
893 state = NULL;
894 xfs_defer_init(args->dfops, args->firstblock);
895 error = xfs_attr3_leaf_to_node(args);
896 if (error)
897 goto out_defer_cancel;
898 xfs_defer_ijoin(args->dfops, dp);
899 error = xfs_defer_finish(&args->trans, args->dfops);
900 if (error)
901 goto out_defer_cancel;
902
903 /*
904 * Commit the node conversion and start the next
905 * trans in the chain.
906 */
907 error = xfs_trans_roll_inode(&args->trans, dp);
908 if (error)
909 goto out;
910
911 goto restart;
912 }
913
914 /*
915 * Split as many Btree elements as required.
916 * This code tracks the new and old attr's location
917 * in the index/blkno/rmtblkno/rmtblkcnt fields and
918 * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
919 */
920 xfs_defer_init(args->dfops, args->firstblock);
921 error = xfs_da3_split(state);
922 if (error)
923 goto out_defer_cancel;
924 xfs_defer_ijoin(args->dfops, dp);
925 error = xfs_defer_finish(&args->trans, args->dfops);
926 if (error)
927 goto out_defer_cancel;
928 } else {
929 /*
930 * Addition succeeded, update Btree hashvals.
931 */
932 xfs_da3_fixhashpath(state, &state->path);
933 }
934
935 /*
936 * Kill the state structure, we're done with it and need to
937 * allow the buffers to come back later.
938 */
939 xfs_da_state_free(state);
940 state = NULL;
941
942 /*
943 * Commit the leaf addition or btree split and start the next
944 * trans in the chain.
945 */
946 error = xfs_trans_roll_inode(&args->trans, dp);
947 if (error)
948 goto out;
949
950 /*
951 * If there was an out-of-line value, allocate the blocks we
952 * identified for its storage and copy the value. This is done
953 * after we create the attribute so that we don't overflow the
954 * maximum size of a transaction and/or hit a deadlock.
955 */
956 if (args->rmtblkno > 0) {
957 error = xfs_attr_rmtval_set(args);
958 if (error)
959 return error;
960 }
961
962 /*
963 * If this is an atomic rename operation, we must "flip" the
964 * incomplete flags on the "new" and "old" attribute/value pairs
965 * so that one disappears and one appears atomically. Then we
966 * must remove the "old" attribute/value pair.
967 */
968 if (args->op_flags & XFS_DA_OP_RENAME) {
969 /*
970 * In a separate transaction, set the incomplete flag on the
971 * "old" attr and clear the incomplete flag on the "new" attr.
972 */
973 error = xfs_attr3_leaf_flipflags(args);
974 if (error)
975 goto out;
976
977 /*
978 * Dismantle the "old" attribute/value pair by removing
979 * a "remote" value (if it exists).
980 */
981 args->index = args->index2;
982 args->blkno = args->blkno2;
983 args->rmtblkno = args->rmtblkno2;
984 args->rmtblkcnt = args->rmtblkcnt2;
985 args->rmtvaluelen = args->rmtvaluelen2;
986 if (args->rmtblkno) {
987 error = xfs_attr_rmtval_remove(args);
988 if (error)
989 return error;
990 }
991
992 /*
993 * Re-find the "old" attribute entry after any split ops.
994 * The INCOMPLETE flag means that we will find the "old"
995 * attr, not the "new" one.
996 */
997 args->flags |= XFS_ATTR_INCOMPLETE;
998 state = xfs_da_state_alloc();
999 state->args = args;
1000 state->mp = mp;
1001 state->inleaf = 0;
1002 error = xfs_da3_node_lookup_int(state, &retval);
1003 if (error)
1004 goto out;
1005
1006 /*
1007 * Remove the name and update the hashvals in the tree.
1008 */
1009 blk = &state->path.blk[ state->path.active-1 ];
1010 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1011 error = xfs_attr3_leaf_remove(blk->bp, args);
1012 xfs_da3_fixhashpath(state, &state->path);
1013
1014 /*
1015 * Check to see if the tree needs to be collapsed.
1016 */
1017 if (retval && (state->path.active > 1)) {
1018 xfs_defer_init(args->dfops, args->firstblock);
1019 error = xfs_da3_join(state);
1020 if (error)
1021 goto out_defer_cancel;
1022 xfs_defer_ijoin(args->dfops, dp);
1023 error = xfs_defer_finish(&args->trans, args->dfops);
1024 if (error)
1025 goto out_defer_cancel;
1026 }
1027
1028 /*
1029 * Commit and start the next trans in the chain.
1030 */
1031 error = xfs_trans_roll_inode(&args->trans, dp);
1032 if (error)
1033 goto out;
1034
1035 } else if (args->rmtblkno > 0) {
1036 /*
1037 * Added a "remote" value, just clear the incomplete flag.
1038 */
1039 error = xfs_attr3_leaf_clearflag(args);
1040 if (error)
1041 goto out;
1042 }
1043 retval = error = 0;
1044
1045out:
1046 if (state)
1047 xfs_da_state_free(state);
1048 if (error)
1049 return error;
1050 return retval;
1051out_defer_cancel:
1052 xfs_defer_cancel(args->dfops);
1053 goto out;
1054}
1055
1056/*
1057 * Remove a name from a B-tree attribute list.
1058 *
1059 * This will involve walking down the Btree, and may involve joining
1060 * leaf nodes and even joining intermediate nodes up to and including
1061 * the root node (a special case of an intermediate node).
1062 */
1063STATIC int
1064xfs_attr_node_removename(xfs_da_args_t *args)
1065{
1066 xfs_da_state_t *state;
1067 xfs_da_state_blk_t *blk;
1068 xfs_inode_t *dp;
1069 struct xfs_buf *bp;
1070 int retval, error, forkoff;
1071
1072 trace_xfs_attr_node_removename(args);
1073
1074 /*
1075 * Tie a string around our finger to remind us where we are.
1076 */
1077 dp = args->dp;
1078 state = xfs_da_state_alloc();
1079 state->args = args;
1080 state->mp = dp->i_mount;
1081
1082 /*
1083 * Search to see if name exists, and get back a pointer to it.
1084 */
1085 error = xfs_da3_node_lookup_int(state, &retval);
1086 if (error || (retval != -EEXIST)) {
1087 if (error == 0)
1088 error = retval;
1089 goto out;
1090 }
1091
1092 /*
1093 * If there is an out-of-line value, de-allocate the blocks.
1094 * This is done before we remove the attribute so that we don't
1095 * overflow the maximum size of a transaction and/or hit a deadlock.
1096 */
1097 blk = &state->path.blk[ state->path.active-1 ];
1098 ASSERT(blk->bp != NULL);
1099 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1100 if (args->rmtblkno > 0) {
1101 /*
1102 * Fill in disk block numbers in the state structure
1103 * so that we can get the buffers back after we commit
1104 * several transactions in the following calls.
1105 */
1106 error = xfs_attr_fillstate(state);
1107 if (error)
1108 goto out;
1109
1110 /*
1111 * Mark the attribute as INCOMPLETE, then bunmapi() the
1112 * remote value.
1113 */
1114 error = xfs_attr3_leaf_setflag(args);
1115 if (error)
1116 goto out;
1117 error = xfs_attr_rmtval_remove(args);
1118 if (error)
1119 goto out;
1120
1121 /*
1122 * Refill the state structure with buffers, the prior calls
1123 * released our buffers.
1124 */
1125 error = xfs_attr_refillstate(state);
1126 if (error)
1127 goto out;
1128 }
1129
1130 /*
1131 * Remove the name and update the hashvals in the tree.
1132 */
1133 blk = &state->path.blk[ state->path.active-1 ];
1134 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1135 retval = xfs_attr3_leaf_remove(blk->bp, args);
1136 xfs_da3_fixhashpath(state, &state->path);
1137
1138 /*
1139 * Check to see if the tree needs to be collapsed.
1140 */
1141 if (retval && (state->path.active > 1)) {
1142 xfs_defer_init(args->dfops, args->firstblock);
1143 error = xfs_da3_join(state);
1144 if (error)
1145 goto out_defer_cancel;
1146 xfs_defer_ijoin(args->dfops, dp);
1147 error = xfs_defer_finish(&args->trans, args->dfops);
1148 if (error)
1149 goto out_defer_cancel;
1150 /*
1151 * Commit the Btree join operation and start a new trans.
1152 */
1153 error = xfs_trans_roll_inode(&args->trans, dp);
1154 if (error)
1155 goto out;
1156 }
1157
1158 /*
1159 * If the result is small enough, push it all into the inode.
1160 */
1161 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
1162 /*
1163 * Have to get rid of the copy of this dabuf in the state.
1164 */
1165 ASSERT(state->path.active == 1);
1166 ASSERT(state->path.blk[0].bp);
1167 state->path.blk[0].bp = NULL;
1168
1169 error = xfs_attr3_leaf_read(args->trans, args->dp, 0, -1, &bp);
1170 if (error)
1171 goto out;
1172
1173 if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
1174 xfs_defer_init(args->dfops, args->firstblock);
1175 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
1176 /* bp is gone due to xfs_da_shrink_inode */
1177 if (error)
1178 goto out_defer_cancel;
1179 xfs_defer_ijoin(args->dfops, dp);
1180 error = xfs_defer_finish(&args->trans, args->dfops);
1181 if (error)
1182 goto out_defer_cancel;
1183 } else
1184 xfs_trans_brelse(args->trans, bp);
1185 }
1186 error = 0;
1187
1188out:
1189 xfs_da_state_free(state);
1190 return error;
1191out_defer_cancel:
1192 xfs_defer_cancel(args->dfops);
1193 goto out;
1194}
1195
1196/*
1197 * Fill in the disk block numbers in the state structure for the buffers
1198 * that are attached to the state structure.
1199 * This is done so that we can quickly reattach ourselves to those buffers
1200 * after some set of transaction commits have released these buffers.
1201 */
1202STATIC int
1203xfs_attr_fillstate(xfs_da_state_t *state)
1204{
1205 xfs_da_state_path_t *path;
1206 xfs_da_state_blk_t *blk;
1207 int level;
1208
1209 trace_xfs_attr_fillstate(state->args);
1210
1211 /*
1212 * Roll down the "path" in the state structure, storing the on-disk
1213 * block number for those buffers in the "path".
1214 */
1215 path = &state->path;
1216 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1217 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1218 if (blk->bp) {
1219 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1220 blk->bp = NULL;
1221 } else {
1222 blk->disk_blkno = 0;
1223 }
1224 }
1225
1226 /*
1227 * Roll down the "altpath" in the state structure, storing the on-disk
1228 * block number for those buffers in the "altpath".
1229 */
1230 path = &state->altpath;
1231 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1232 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1233 if (blk->bp) {
1234 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1235 blk->bp = NULL;
1236 } else {
1237 blk->disk_blkno = 0;
1238 }
1239 }
1240
1241 return 0;
1242}
1243
1244/*
1245 * Reattach the buffers to the state structure based on the disk block
1246 * numbers stored in the state structure.
1247 * This is done after some set of transaction commits have released those
1248 * buffers from our grip.
1249 */
1250STATIC int
1251xfs_attr_refillstate(xfs_da_state_t *state)
1252{
1253 xfs_da_state_path_t *path;
1254 xfs_da_state_blk_t *blk;
1255 int level, error;
1256
1257 trace_xfs_attr_refillstate(state->args);
1258
1259 /*
1260 * Roll down the "path" in the state structure, storing the on-disk
1261 * block number for those buffers in the "path".
1262 */
1263 path = &state->path;
1264 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1265 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1266 if (blk->disk_blkno) {
1267 error = xfs_da3_node_read(state->args->trans,
1268 state->args->dp,
1269 blk->blkno, blk->disk_blkno,
1270 &blk->bp, XFS_ATTR_FORK);
1271 if (error)
1272 return error;
1273 } else {
1274 blk->bp = NULL;
1275 }
1276 }
1277
1278 /*
1279 * Roll down the "altpath" in the state structure, storing the on-disk
1280 * block number for those buffers in the "altpath".
1281 */
1282 path = &state->altpath;
1283 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1284 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1285 if (blk->disk_blkno) {
1286 error = xfs_da3_node_read(state->args->trans,
1287 state->args->dp,
1288 blk->blkno, blk->disk_blkno,
1289 &blk->bp, XFS_ATTR_FORK);
1290 if (error)
1291 return error;
1292 } else {
1293 blk->bp = NULL;
1294 }
1295 }
1296
1297 return 0;
1298}
1299
1300/*
1301 * Look up a filename in a node attribute list.
1302 *
1303 * This routine gets called for any attribute fork that has more than one
1304 * block, ie: both true Btree attr lists and for single-leaf-blocks with
1305 * "remote" values taking up more blocks.
1306 */
1307STATIC int
1308xfs_attr_node_get(xfs_da_args_t *args)
1309{
1310 xfs_da_state_t *state;
1311 xfs_da_state_blk_t *blk;
1312 int error, retval;
1313 int i;
1314
1315 trace_xfs_attr_node_get(args);
1316
1317 state = xfs_da_state_alloc();
1318 state->args = args;
1319 state->mp = args->dp->i_mount;
1320
1321 /*
1322 * Search to see if name exists, and get back a pointer to it.
1323 */
1324 error = xfs_da3_node_lookup_int(state, &retval);
1325 if (error) {
1326 retval = error;
1327 } else if (retval == -EEXIST) {
1328 blk = &state->path.blk[ state->path.active-1 ];
1329 ASSERT(blk->bp != NULL);
1330 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1331
1332 /*
1333 * Get the value, local or "remote"
1334 */
1335 retval = xfs_attr3_leaf_getvalue(blk->bp, args);
1336 if (!retval && (args->rmtblkno > 0)
1337 && !(args->flags & ATTR_KERNOVAL)) {
1338 retval = xfs_attr_rmtval_get(args);
1339 }
1340 }
1341
1342 /*
1343 * If not in a transaction, we have to release all the buffers.
1344 */
1345 for (i = 0; i < state->path.active; i++) {
1346 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1347 state->path.blk[i].bp = NULL;
1348 }
1349
1350 xfs_da_state_free(state);
1351 return retval;
1352}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_log_format.h"
11#include "xfs_trans_resv.h"
12#include "xfs_mount.h"
13#include "xfs_defer.h"
14#include "xfs_da_format.h"
15#include "xfs_da_btree.h"
16#include "xfs_attr_sf.h"
17#include "xfs_inode.h"
18#include "xfs_trans.h"
19#include "xfs_bmap.h"
20#include "xfs_bmap_btree.h"
21#include "xfs_attr.h"
22#include "xfs_attr_leaf.h"
23#include "xfs_attr_remote.h"
24#include "xfs_quota.h"
25#include "xfs_trans_space.h"
26#include "xfs_trace.h"
27
28/*
29 * xfs_attr.c
30 *
31 * Provide the external interfaces to manage attribute lists.
32 */
33
34/*========================================================================
35 * Function prototypes for the kernel.
36 *========================================================================*/
37
38/*
39 * Internal routines when attribute list fits inside the inode.
40 */
41STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
42
43/*
44 * Internal routines when attribute list is one block.
45 */
46STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
47STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
48STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
49STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
50
51/*
52 * Internal routines when attribute list is more than one block.
53 */
54STATIC int xfs_attr_node_get(xfs_da_args_t *args);
55STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
56STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
57STATIC int xfs_attr_node_hasname(xfs_da_args_t *args,
58 struct xfs_da_state **state);
59STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
60STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
61
62int
63xfs_inode_hasattr(
64 struct xfs_inode *ip)
65{
66 if (!XFS_IFORK_Q(ip) ||
67 (ip->i_afp->if_format == XFS_DINODE_FMT_EXTENTS &&
68 ip->i_afp->if_nextents == 0))
69 return 0;
70 return 1;
71}
72
73/*========================================================================
74 * Overall external interface routines.
75 *========================================================================*/
76
77/*
78 * Retrieve an extended attribute and its value. Must have ilock.
79 * Returns 0 on successful retrieval, otherwise an error.
80 */
81int
82xfs_attr_get_ilocked(
83 struct xfs_da_args *args)
84{
85 ASSERT(xfs_isilocked(args->dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
86
87 if (!xfs_inode_hasattr(args->dp))
88 return -ENOATTR;
89
90 if (args->dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL)
91 return xfs_attr_shortform_getvalue(args);
92 if (xfs_bmap_one_block(args->dp, XFS_ATTR_FORK))
93 return xfs_attr_leaf_get(args);
94 return xfs_attr_node_get(args);
95}
96
97/*
98 * Retrieve an extended attribute by name, and its value if requested.
99 *
100 * If args->valuelen is zero, then the caller does not want the value, just an
101 * indication whether the attribute exists and the size of the value if it
102 * exists. The size is returned in args.valuelen.
103 *
104 * If args->value is NULL but args->valuelen is non-zero, allocate the buffer
105 * for the value after existence of the attribute has been determined. The
106 * caller always has to free args->value if it is set, no matter if this
107 * function was successful or not.
108 *
109 * If the attribute is found, but exceeds the size limit set by the caller in
110 * args->valuelen, return -ERANGE with the size of the attribute that was found
111 * in args->valuelen.
112 */
113int
114xfs_attr_get(
115 struct xfs_da_args *args)
116{
117 uint lock_mode;
118 int error;
119
120 XFS_STATS_INC(args->dp->i_mount, xs_attr_get);
121
122 if (XFS_FORCED_SHUTDOWN(args->dp->i_mount))
123 return -EIO;
124
125 args->geo = args->dp->i_mount->m_attr_geo;
126 args->whichfork = XFS_ATTR_FORK;
127 args->hashval = xfs_da_hashname(args->name, args->namelen);
128
129 /* Entirely possible to look up a name which doesn't exist */
130 args->op_flags = XFS_DA_OP_OKNOENT;
131
132 lock_mode = xfs_ilock_attr_map_shared(args->dp);
133 error = xfs_attr_get_ilocked(args);
134 xfs_iunlock(args->dp, lock_mode);
135
136 return error;
137}
138
139/*
140 * Calculate how many blocks we need for the new attribute,
141 */
142STATIC int
143xfs_attr_calc_size(
144 struct xfs_da_args *args,
145 int *local)
146{
147 struct xfs_mount *mp = args->dp->i_mount;
148 int size;
149 int nblks;
150
151 /*
152 * Determine space new attribute will use, and if it would be
153 * "local" or "remote" (note: local != inline).
154 */
155 size = xfs_attr_leaf_newentsize(args, local);
156 nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
157 if (*local) {
158 if (size > (args->geo->blksize / 2)) {
159 /* Double split possible */
160 nblks *= 2;
161 }
162 } else {
163 /*
164 * Out of line attribute, cannot double split, but
165 * make room for the attribute value itself.
166 */
167 uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
168 nblks += dblocks;
169 nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
170 }
171
172 return nblks;
173}
174
175STATIC int
176xfs_attr_try_sf_addname(
177 struct xfs_inode *dp,
178 struct xfs_da_args *args)
179{
180
181 int error;
182
183 /*
184 * Build initial attribute list (if required).
185 */
186 if (dp->i_afp->if_format == XFS_DINODE_FMT_EXTENTS)
187 xfs_attr_shortform_create(args);
188
189 error = xfs_attr_shortform_addname(args);
190 if (error == -ENOSPC)
191 return error;
192
193 /*
194 * Commit the shortform mods, and we're done.
195 * NOTE: this is also the error path (EEXIST, etc).
196 */
197 if (!error && !(args->op_flags & XFS_DA_OP_NOTIME))
198 xfs_trans_ichgtime(args->trans, dp, XFS_ICHGTIME_CHG);
199
200 if (dp->i_mount->m_flags & XFS_MOUNT_WSYNC)
201 xfs_trans_set_sync(args->trans);
202
203 return error;
204}
205
206/*
207 * Check to see if the attr should be upgraded from non-existent or shortform to
208 * single-leaf-block attribute list.
209 */
210static inline bool
211xfs_attr_is_shortform(
212 struct xfs_inode *ip)
213{
214 return ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL ||
215 (ip->i_afp->if_format == XFS_DINODE_FMT_EXTENTS &&
216 ip->i_afp->if_nextents == 0);
217}
218
219/*
220 * Attempts to set an attr in shortform, or converts short form to leaf form if
221 * there is not enough room. If the attr is set, the transaction is committed
222 * and set to NULL.
223 */
224STATIC int
225xfs_attr_set_shortform(
226 struct xfs_da_args *args,
227 struct xfs_buf **leaf_bp)
228{
229 struct xfs_inode *dp = args->dp;
230 int error, error2 = 0;
231
232 /*
233 * Try to add the attr to the attribute list in the inode.
234 */
235 error = xfs_attr_try_sf_addname(dp, args);
236 if (error != -ENOSPC) {
237 error2 = xfs_trans_commit(args->trans);
238 args->trans = NULL;
239 return error ? error : error2;
240 }
241 /*
242 * It won't fit in the shortform, transform to a leaf block. GROT:
243 * another possible req'mt for a double-split btree op.
244 */
245 error = xfs_attr_shortform_to_leaf(args, leaf_bp);
246 if (error)
247 return error;
248
249 /*
250 * Prevent the leaf buffer from being unlocked so that a concurrent AIL
251 * push cannot grab the half-baked leaf buffer and run into problems
252 * with the write verifier. Once we're done rolling the transaction we
253 * can release the hold and add the attr to the leaf.
254 */
255 xfs_trans_bhold(args->trans, *leaf_bp);
256 error = xfs_defer_finish(&args->trans);
257 xfs_trans_bhold_release(args->trans, *leaf_bp);
258 if (error) {
259 xfs_trans_brelse(args->trans, *leaf_bp);
260 return error;
261 }
262
263 return 0;
264}
265
266/*
267 * Set the attribute specified in @args.
268 */
269int
270xfs_attr_set_args(
271 struct xfs_da_args *args)
272{
273 struct xfs_inode *dp = args->dp;
274 struct xfs_buf *leaf_bp = NULL;
275 int error = 0;
276
277 /*
278 * If the attribute list is already in leaf format, jump straight to
279 * leaf handling. Otherwise, try to add the attribute to the shortform
280 * list; if there's no room then convert the list to leaf format and try
281 * again.
282 */
283 if (xfs_attr_is_shortform(dp)) {
284
285 /*
286 * If the attr was successfully set in shortform, the
287 * transaction is committed and set to NULL. Otherwise, is it
288 * converted from shortform to leaf, and the transaction is
289 * retained.
290 */
291 error = xfs_attr_set_shortform(args, &leaf_bp);
292 if (error || !args->trans)
293 return error;
294 }
295
296 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
297 error = xfs_attr_leaf_addname(args);
298 if (error != -ENOSPC)
299 return error;
300
301 /*
302 * Promote the attribute list to the Btree format.
303 */
304 error = xfs_attr3_leaf_to_node(args);
305 if (error)
306 return error;
307
308 /*
309 * Finish any deferred work items and roll the transaction once
310 * more. The goal here is to call node_addname with the inode
311 * and transaction in the same state (inode locked and joined,
312 * transaction clean) no matter how we got to this step.
313 */
314 error = xfs_defer_finish(&args->trans);
315 if (error)
316 return error;
317
318 /*
319 * Commit the current trans (including the inode) and
320 * start a new one.
321 */
322 error = xfs_trans_roll_inode(&args->trans, dp);
323 if (error)
324 return error;
325 }
326
327 error = xfs_attr_node_addname(args);
328 return error;
329}
330
331/*
332 * Return EEXIST if attr is found, or ENOATTR if not
333 */
334int
335xfs_has_attr(
336 struct xfs_da_args *args)
337{
338 struct xfs_inode *dp = args->dp;
339 struct xfs_buf *bp = NULL;
340 int error;
341
342 if (!xfs_inode_hasattr(dp))
343 return -ENOATTR;
344
345 if (dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL) {
346 ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
347 return xfs_attr_sf_findname(args, NULL, NULL);
348 }
349
350 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
351 error = xfs_attr_leaf_hasname(args, &bp);
352
353 if (bp)
354 xfs_trans_brelse(args->trans, bp);
355
356 return error;
357 }
358
359 return xfs_attr_node_hasname(args, NULL);
360}
361
362/*
363 * Remove the attribute specified in @args.
364 */
365int
366xfs_attr_remove_args(
367 struct xfs_da_args *args)
368{
369 struct xfs_inode *dp = args->dp;
370 int error;
371
372 if (!xfs_inode_hasattr(dp)) {
373 error = -ENOATTR;
374 } else if (dp->i_afp->if_format == XFS_DINODE_FMT_LOCAL) {
375 ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
376 error = xfs_attr_shortform_remove(args);
377 } else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
378 error = xfs_attr_leaf_removename(args);
379 } else {
380 error = xfs_attr_node_removename(args);
381 }
382
383 return error;
384}
385
386/*
387 * Note: If args->value is NULL the attribute will be removed, just like the
388 * Linux ->setattr API.
389 */
390int
391xfs_attr_set(
392 struct xfs_da_args *args)
393{
394 struct xfs_inode *dp = args->dp;
395 struct xfs_mount *mp = dp->i_mount;
396 struct xfs_trans_res tres;
397 bool rsvd = (args->attr_filter & XFS_ATTR_ROOT);
398 int error, local;
399 unsigned int total;
400
401 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
402 return -EIO;
403
404 error = xfs_qm_dqattach(dp);
405 if (error)
406 return error;
407
408 args->geo = mp->m_attr_geo;
409 args->whichfork = XFS_ATTR_FORK;
410 args->hashval = xfs_da_hashname(args->name, args->namelen);
411
412 /*
413 * We have no control over the attribute names that userspace passes us
414 * to remove, so we have to allow the name lookup prior to attribute
415 * removal to fail as well.
416 */
417 args->op_flags = XFS_DA_OP_OKNOENT;
418
419 if (args->value) {
420 XFS_STATS_INC(mp, xs_attr_set);
421
422 args->op_flags |= XFS_DA_OP_ADDNAME;
423 args->total = xfs_attr_calc_size(args, &local);
424
425 /*
426 * If the inode doesn't have an attribute fork, add one.
427 * (inode must not be locked when we call this routine)
428 */
429 if (XFS_IFORK_Q(dp) == 0) {
430 int sf_size = sizeof(struct xfs_attr_sf_hdr) +
431 XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen,
432 args->valuelen);
433
434 error = xfs_bmap_add_attrfork(dp, sf_size, rsvd);
435 if (error)
436 return error;
437 }
438
439 tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
440 M_RES(mp)->tr_attrsetrt.tr_logres *
441 args->total;
442 tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
443 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
444 total = args->total;
445 } else {
446 XFS_STATS_INC(mp, xs_attr_remove);
447
448 tres = M_RES(mp)->tr_attrrm;
449 total = XFS_ATTRRM_SPACE_RES(mp);
450 }
451
452 /*
453 * Root fork attributes can use reserved data blocks for this
454 * operation if necessary
455 */
456 error = xfs_trans_alloc(mp, &tres, total, 0,
457 rsvd ? XFS_TRANS_RESERVE : 0, &args->trans);
458 if (error)
459 return error;
460
461 xfs_ilock(dp, XFS_ILOCK_EXCL);
462 xfs_trans_ijoin(args->trans, dp, 0);
463 if (args->value) {
464 unsigned int quota_flags = XFS_QMOPT_RES_REGBLKS;
465
466 if (rsvd)
467 quota_flags |= XFS_QMOPT_FORCE_RES;
468 error = xfs_trans_reserve_quota_nblks(args->trans, dp,
469 args->total, 0, quota_flags);
470 if (error)
471 goto out_trans_cancel;
472
473 error = xfs_has_attr(args);
474 if (error == -EEXIST && (args->attr_flags & XATTR_CREATE))
475 goto out_trans_cancel;
476 if (error == -ENOATTR && (args->attr_flags & XATTR_REPLACE))
477 goto out_trans_cancel;
478 if (error != -ENOATTR && error != -EEXIST)
479 goto out_trans_cancel;
480
481 error = xfs_attr_set_args(args);
482 if (error)
483 goto out_trans_cancel;
484 /* shortform attribute has already been committed */
485 if (!args->trans)
486 goto out_unlock;
487 } else {
488 error = xfs_has_attr(args);
489 if (error != -EEXIST)
490 goto out_trans_cancel;
491
492 error = xfs_attr_remove_args(args);
493 if (error)
494 goto out_trans_cancel;
495 }
496
497 /*
498 * If this is a synchronous mount, make sure that the
499 * transaction goes to disk before returning to the user.
500 */
501 if (mp->m_flags & XFS_MOUNT_WSYNC)
502 xfs_trans_set_sync(args->trans);
503
504 if (!(args->op_flags & XFS_DA_OP_NOTIME))
505 xfs_trans_ichgtime(args->trans, dp, XFS_ICHGTIME_CHG);
506
507 /*
508 * Commit the last in the sequence of transactions.
509 */
510 xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
511 error = xfs_trans_commit(args->trans);
512out_unlock:
513 xfs_iunlock(dp, XFS_ILOCK_EXCL);
514 return error;
515
516out_trans_cancel:
517 if (args->trans)
518 xfs_trans_cancel(args->trans);
519 goto out_unlock;
520}
521
522/*========================================================================
523 * External routines when attribute list is inside the inode
524 *========================================================================*/
525
526/*
527 * Add a name to the shortform attribute list structure
528 * This is the external routine.
529 */
530STATIC int
531xfs_attr_shortform_addname(xfs_da_args_t *args)
532{
533 int newsize, forkoff, retval;
534
535 trace_xfs_attr_sf_addname(args);
536
537 retval = xfs_attr_shortform_lookup(args);
538 if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE))
539 return retval;
540 if (retval == -EEXIST) {
541 if (args->attr_flags & XATTR_CREATE)
542 return retval;
543 retval = xfs_attr_shortform_remove(args);
544 if (retval)
545 return retval;
546 /*
547 * Since we have removed the old attr, clear ATTR_REPLACE so
548 * that the leaf format add routine won't trip over the attr
549 * not being around.
550 */
551 args->attr_flags &= ~XATTR_REPLACE;
552 }
553
554 if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
555 args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
556 return -ENOSPC;
557
558 newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
559 newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
560
561 forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
562 if (!forkoff)
563 return -ENOSPC;
564
565 xfs_attr_shortform_add(args, forkoff);
566 return 0;
567}
568
569
570/*========================================================================
571 * External routines when attribute list is one block
572 *========================================================================*/
573
574/* Store info about a remote block */
575STATIC void
576xfs_attr_save_rmt_blk(
577 struct xfs_da_args *args)
578{
579 args->blkno2 = args->blkno;
580 args->index2 = args->index;
581 args->rmtblkno2 = args->rmtblkno;
582 args->rmtblkcnt2 = args->rmtblkcnt;
583 args->rmtvaluelen2 = args->rmtvaluelen;
584}
585
586/* Set stored info about a remote block */
587STATIC void
588xfs_attr_restore_rmt_blk(
589 struct xfs_da_args *args)
590{
591 args->blkno = args->blkno2;
592 args->index = args->index2;
593 args->rmtblkno = args->rmtblkno2;
594 args->rmtblkcnt = args->rmtblkcnt2;
595 args->rmtvaluelen = args->rmtvaluelen2;
596}
597
598/*
599 * Tries to add an attribute to an inode in leaf form
600 *
601 * This function is meant to execute as part of a delayed operation and leaves
602 * the transaction handling to the caller. On success the attribute is added
603 * and the inode and transaction are left dirty. If there is not enough space,
604 * the attr data is converted to node format and -ENOSPC is returned. Caller is
605 * responsible for handling the dirty inode and transaction or adding the attr
606 * in node format.
607 */
608STATIC int
609xfs_attr_leaf_try_add(
610 struct xfs_da_args *args,
611 struct xfs_buf *bp)
612{
613 int retval;
614
615 /*
616 * Look up the given attribute in the leaf block. Figure out if
617 * the given flags produce an error or call for an atomic rename.
618 */
619 retval = xfs_attr_leaf_hasname(args, &bp);
620 if (retval != -ENOATTR && retval != -EEXIST)
621 return retval;
622 if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE))
623 goto out_brelse;
624 if (retval == -EEXIST) {
625 if (args->attr_flags & XATTR_CREATE)
626 goto out_brelse;
627
628 trace_xfs_attr_leaf_replace(args);
629
630 /* save the attribute state for later removal*/
631 args->op_flags |= XFS_DA_OP_RENAME; /* an atomic rename */
632 xfs_attr_save_rmt_blk(args);
633
634 /*
635 * clear the remote attr state now that it is saved so that the
636 * values reflect the state of the attribute we are about to
637 * add, not the attribute we just found and will remove later.
638 */
639 args->rmtblkno = 0;
640 args->rmtblkcnt = 0;
641 args->rmtvaluelen = 0;
642 }
643
644 /*
645 * Add the attribute to the leaf block
646 */
647 return xfs_attr3_leaf_add(bp, args);
648
649out_brelse:
650 xfs_trans_brelse(args->trans, bp);
651 return retval;
652}
653
654
655/*
656 * Add a name to the leaf attribute list structure
657 *
658 * This leaf block cannot have a "remote" value, we only call this routine
659 * if bmap_one_block() says there is only one block (ie: no remote blks).
660 */
661STATIC int
662xfs_attr_leaf_addname(
663 struct xfs_da_args *args)
664{
665 int error, forkoff;
666 struct xfs_buf *bp = NULL;
667 struct xfs_inode *dp = args->dp;
668
669 trace_xfs_attr_leaf_addname(args);
670
671 error = xfs_attr_leaf_try_add(args, bp);
672 if (error)
673 return error;
674
675 /*
676 * Commit the transaction that added the attr name so that
677 * later routines can manage their own transactions.
678 */
679 error = xfs_trans_roll_inode(&args->trans, dp);
680 if (error)
681 return error;
682
683 /*
684 * If there was an out-of-line value, allocate the blocks we
685 * identified for its storage and copy the value. This is done
686 * after we create the attribute so that we don't overflow the
687 * maximum size of a transaction and/or hit a deadlock.
688 */
689 if (args->rmtblkno > 0) {
690 error = xfs_attr_rmtval_set(args);
691 if (error)
692 return error;
693 }
694
695 if (!(args->op_flags & XFS_DA_OP_RENAME)) {
696 /*
697 * Added a "remote" value, just clear the incomplete flag.
698 */
699 if (args->rmtblkno > 0)
700 error = xfs_attr3_leaf_clearflag(args);
701
702 return error;
703 }
704
705 /*
706 * If this is an atomic rename operation, we must "flip" the incomplete
707 * flags on the "new" and "old" attribute/value pairs so that one
708 * disappears and one appears atomically. Then we must remove the "old"
709 * attribute/value pair.
710 *
711 * In a separate transaction, set the incomplete flag on the "old" attr
712 * and clear the incomplete flag on the "new" attr.
713 */
714
715 error = xfs_attr3_leaf_flipflags(args);
716 if (error)
717 return error;
718 /*
719 * Commit the flag value change and start the next trans in series.
720 */
721 error = xfs_trans_roll_inode(&args->trans, args->dp);
722 if (error)
723 return error;
724
725 /*
726 * Dismantle the "old" attribute/value pair by removing a "remote" value
727 * (if it exists).
728 */
729 xfs_attr_restore_rmt_blk(args);
730
731 if (args->rmtblkno) {
732 error = xfs_attr_rmtval_invalidate(args);
733 if (error)
734 return error;
735
736 error = xfs_attr_rmtval_remove(args);
737 if (error)
738 return error;
739 }
740
741 /*
742 * Read in the block containing the "old" attr, then remove the "old"
743 * attr from that block (neat, huh!)
744 */
745 error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
746 &bp);
747 if (error)
748 return error;
749
750 xfs_attr3_leaf_remove(bp, args);
751
752 /*
753 * If the result is small enough, shrink it all into the inode.
754 */
755 forkoff = xfs_attr_shortform_allfit(bp, dp);
756 if (forkoff)
757 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
758 /* bp is gone due to xfs_da_shrink_inode */
759
760 return error;
761}
762
763/*
764 * Return EEXIST if attr is found, or ENOATTR if not
765 */
766STATIC int
767xfs_attr_leaf_hasname(
768 struct xfs_da_args *args,
769 struct xfs_buf **bp)
770{
771 int error = 0;
772
773 error = xfs_attr3_leaf_read(args->trans, args->dp, 0, bp);
774 if (error)
775 return error;
776
777 error = xfs_attr3_leaf_lookup_int(*bp, args);
778 if (error != -ENOATTR && error != -EEXIST)
779 xfs_trans_brelse(args->trans, *bp);
780
781 return error;
782}
783
784/*
785 * Remove a name from the leaf attribute list structure
786 *
787 * This leaf block cannot have a "remote" value, we only call this routine
788 * if bmap_one_block() says there is only one block (ie: no remote blks).
789 */
790STATIC int
791xfs_attr_leaf_removename(
792 struct xfs_da_args *args)
793{
794 struct xfs_inode *dp;
795 struct xfs_buf *bp;
796 int error, forkoff;
797
798 trace_xfs_attr_leaf_removename(args);
799
800 /*
801 * Remove the attribute.
802 */
803 dp = args->dp;
804
805 error = xfs_attr_leaf_hasname(args, &bp);
806
807 if (error == -ENOATTR) {
808 xfs_trans_brelse(args->trans, bp);
809 return error;
810 } else if (error != -EEXIST)
811 return error;
812
813 xfs_attr3_leaf_remove(bp, args);
814
815 /*
816 * If the result is small enough, shrink it all into the inode.
817 */
818 forkoff = xfs_attr_shortform_allfit(bp, dp);
819 if (forkoff)
820 return xfs_attr3_leaf_to_shortform(bp, args, forkoff);
821 /* bp is gone due to xfs_da_shrink_inode */
822
823 return 0;
824}
825
826/*
827 * Look up a name in a leaf attribute list structure.
828 *
829 * This leaf block cannot have a "remote" value, we only call this routine
830 * if bmap_one_block() says there is only one block (ie: no remote blks).
831 *
832 * Returns 0 on successful retrieval, otherwise an error.
833 */
834STATIC int
835xfs_attr_leaf_get(xfs_da_args_t *args)
836{
837 struct xfs_buf *bp;
838 int error;
839
840 trace_xfs_attr_leaf_get(args);
841
842 error = xfs_attr_leaf_hasname(args, &bp);
843
844 if (error == -ENOATTR) {
845 xfs_trans_brelse(args->trans, bp);
846 return error;
847 } else if (error != -EEXIST)
848 return error;
849
850
851 error = xfs_attr3_leaf_getvalue(bp, args);
852 xfs_trans_brelse(args->trans, bp);
853 return error;
854}
855
856/*
857 * Return EEXIST if attr is found, or ENOATTR if not
858 * statep: If not null is set to point at the found state. Caller will
859 * be responsible for freeing the state in this case.
860 */
861STATIC int
862xfs_attr_node_hasname(
863 struct xfs_da_args *args,
864 struct xfs_da_state **statep)
865{
866 struct xfs_da_state *state;
867 int retval, error;
868
869 state = xfs_da_state_alloc(args);
870 if (statep != NULL)
871 *statep = NULL;
872
873 /*
874 * Search to see if name exists, and get back a pointer to it.
875 */
876 error = xfs_da3_node_lookup_int(state, &retval);
877 if (error) {
878 xfs_da_state_free(state);
879 return error;
880 }
881
882 if (statep != NULL)
883 *statep = state;
884 else
885 xfs_da_state_free(state);
886 return retval;
887}
888
889/*========================================================================
890 * External routines when attribute list size > geo->blksize
891 *========================================================================*/
892
893/*
894 * Add a name to a Btree-format attribute list.
895 *
896 * This will involve walking down the Btree, and may involve splitting
897 * leaf nodes and even splitting intermediate nodes up to and including
898 * the root node (a special case of an intermediate node).
899 *
900 * "Remote" attribute values confuse the issue and atomic rename operations
901 * add a whole extra layer of confusion on top of that.
902 */
903STATIC int
904xfs_attr_node_addname(
905 struct xfs_da_args *args)
906{
907 struct xfs_da_state *state;
908 struct xfs_da_state_blk *blk;
909 struct xfs_inode *dp;
910 int retval, error;
911
912 trace_xfs_attr_node_addname(args);
913
914 /*
915 * Fill in bucket of arguments/results/context to carry around.
916 */
917 dp = args->dp;
918restart:
919 /*
920 * Search to see if name already exists, and get back a pointer
921 * to where it should go.
922 */
923 retval = xfs_attr_node_hasname(args, &state);
924 if (retval != -ENOATTR && retval != -EEXIST)
925 goto out;
926
927 blk = &state->path.blk[ state->path.active-1 ];
928 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
929 if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE))
930 goto out;
931 if (retval == -EEXIST) {
932 if (args->attr_flags & XATTR_CREATE)
933 goto out;
934
935 trace_xfs_attr_node_replace(args);
936
937 /* save the attribute state for later removal*/
938 args->op_flags |= XFS_DA_OP_RENAME; /* atomic rename op */
939 xfs_attr_save_rmt_blk(args);
940
941 /*
942 * clear the remote attr state now that it is saved so that the
943 * values reflect the state of the attribute we are about to
944 * add, not the attribute we just found and will remove later.
945 */
946 args->rmtblkno = 0;
947 args->rmtblkcnt = 0;
948 args->rmtvaluelen = 0;
949 }
950
951 retval = xfs_attr3_leaf_add(blk->bp, state->args);
952 if (retval == -ENOSPC) {
953 if (state->path.active == 1) {
954 /*
955 * Its really a single leaf node, but it had
956 * out-of-line values so it looked like it *might*
957 * have been a b-tree.
958 */
959 xfs_da_state_free(state);
960 state = NULL;
961 error = xfs_attr3_leaf_to_node(args);
962 if (error)
963 goto out;
964 error = xfs_defer_finish(&args->trans);
965 if (error)
966 goto out;
967
968 /*
969 * Commit the node conversion and start the next
970 * trans in the chain.
971 */
972 error = xfs_trans_roll_inode(&args->trans, dp);
973 if (error)
974 goto out;
975
976 goto restart;
977 }
978
979 /*
980 * Split as many Btree elements as required.
981 * This code tracks the new and old attr's location
982 * in the index/blkno/rmtblkno/rmtblkcnt fields and
983 * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
984 */
985 error = xfs_da3_split(state);
986 if (error)
987 goto out;
988 error = xfs_defer_finish(&args->trans);
989 if (error)
990 goto out;
991 } else {
992 /*
993 * Addition succeeded, update Btree hashvals.
994 */
995 xfs_da3_fixhashpath(state, &state->path);
996 }
997
998 /*
999 * Kill the state structure, we're done with it and need to
1000 * allow the buffers to come back later.
1001 */
1002 xfs_da_state_free(state);
1003 state = NULL;
1004
1005 /*
1006 * Commit the leaf addition or btree split and start the next
1007 * trans in the chain.
1008 */
1009 error = xfs_trans_roll_inode(&args->trans, dp);
1010 if (error)
1011 goto out;
1012
1013 /*
1014 * If there was an out-of-line value, allocate the blocks we
1015 * identified for its storage and copy the value. This is done
1016 * after we create the attribute so that we don't overflow the
1017 * maximum size of a transaction and/or hit a deadlock.
1018 */
1019 if (args->rmtblkno > 0) {
1020 error = xfs_attr_rmtval_set(args);
1021 if (error)
1022 return error;
1023 }
1024
1025 if (!(args->op_flags & XFS_DA_OP_RENAME)) {
1026 /*
1027 * Added a "remote" value, just clear the incomplete flag.
1028 */
1029 if (args->rmtblkno > 0)
1030 error = xfs_attr3_leaf_clearflag(args);
1031 retval = error;
1032 goto out;
1033 }
1034
1035 /*
1036 * If this is an atomic rename operation, we must "flip" the incomplete
1037 * flags on the "new" and "old" attribute/value pairs so that one
1038 * disappears and one appears atomically. Then we must remove the "old"
1039 * attribute/value pair.
1040 *
1041 * In a separate transaction, set the incomplete flag on the "old" attr
1042 * and clear the incomplete flag on the "new" attr.
1043 */
1044 error = xfs_attr3_leaf_flipflags(args);
1045 if (error)
1046 goto out;
1047 /*
1048 * Commit the flag value change and start the next trans in series
1049 */
1050 error = xfs_trans_roll_inode(&args->trans, args->dp);
1051 if (error)
1052 goto out;
1053
1054 /*
1055 * Dismantle the "old" attribute/value pair by removing a "remote" value
1056 * (if it exists).
1057 */
1058 xfs_attr_restore_rmt_blk(args);
1059
1060 if (args->rmtblkno) {
1061 error = xfs_attr_rmtval_invalidate(args);
1062 if (error)
1063 return error;
1064
1065 error = xfs_attr_rmtval_remove(args);
1066 if (error)
1067 return error;
1068 }
1069
1070 /*
1071 * Re-find the "old" attribute entry after any split ops. The INCOMPLETE
1072 * flag means that we will find the "old" attr, not the "new" one.
1073 */
1074 args->attr_filter |= XFS_ATTR_INCOMPLETE;
1075 state = xfs_da_state_alloc(args);
1076 state->inleaf = 0;
1077 error = xfs_da3_node_lookup_int(state, &retval);
1078 if (error)
1079 goto out;
1080
1081 /*
1082 * Remove the name and update the hashvals in the tree.
1083 */
1084 blk = &state->path.blk[state->path.active-1];
1085 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1086 error = xfs_attr3_leaf_remove(blk->bp, args);
1087 xfs_da3_fixhashpath(state, &state->path);
1088
1089 /*
1090 * Check to see if the tree needs to be collapsed.
1091 */
1092 if (retval && (state->path.active > 1)) {
1093 error = xfs_da3_join(state);
1094 if (error)
1095 goto out;
1096 }
1097 retval = error = 0;
1098
1099out:
1100 if (state)
1101 xfs_da_state_free(state);
1102 if (error)
1103 return error;
1104 return retval;
1105}
1106
1107/*
1108 * Shrink an attribute from leaf to shortform
1109 */
1110STATIC int
1111xfs_attr_node_shrink(
1112 struct xfs_da_args *args,
1113 struct xfs_da_state *state)
1114{
1115 struct xfs_inode *dp = args->dp;
1116 int error, forkoff;
1117 struct xfs_buf *bp;
1118
1119 /*
1120 * Have to get rid of the copy of this dabuf in the state.
1121 */
1122 ASSERT(state->path.active == 1);
1123 ASSERT(state->path.blk[0].bp);
1124 state->path.blk[0].bp = NULL;
1125
1126 error = xfs_attr3_leaf_read(args->trans, args->dp, 0, &bp);
1127 if (error)
1128 return error;
1129
1130 forkoff = xfs_attr_shortform_allfit(bp, dp);
1131 if (forkoff) {
1132 error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
1133 /* bp is gone due to xfs_da_shrink_inode */
1134 } else
1135 xfs_trans_brelse(args->trans, bp);
1136
1137 return error;
1138}
1139
1140/*
1141 * Mark an attribute entry INCOMPLETE and save pointers to the relevant buffers
1142 * for later deletion of the entry.
1143 */
1144STATIC int
1145xfs_attr_leaf_mark_incomplete(
1146 struct xfs_da_args *args,
1147 struct xfs_da_state *state)
1148{
1149 int error;
1150
1151 /*
1152 * Fill in disk block numbers in the state structure
1153 * so that we can get the buffers back after we commit
1154 * several transactions in the following calls.
1155 */
1156 error = xfs_attr_fillstate(state);
1157 if (error)
1158 return error;
1159
1160 /*
1161 * Mark the attribute as INCOMPLETE
1162 */
1163 return xfs_attr3_leaf_setflag(args);
1164}
1165
1166/*
1167 * Initial setup for xfs_attr_node_removename. Make sure the attr is there and
1168 * the blocks are valid. Attr keys with remote blocks will be marked
1169 * incomplete.
1170 */
1171STATIC
1172int xfs_attr_node_removename_setup(
1173 struct xfs_da_args *args,
1174 struct xfs_da_state **state)
1175{
1176 int error;
1177
1178 error = xfs_attr_node_hasname(args, state);
1179 if (error != -EEXIST)
1180 return error;
1181
1182 ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL);
1183 ASSERT((*state)->path.blk[(*state)->path.active - 1].magic ==
1184 XFS_ATTR_LEAF_MAGIC);
1185
1186 if (args->rmtblkno > 0) {
1187 error = xfs_attr_leaf_mark_incomplete(args, *state);
1188 if (error)
1189 return error;
1190
1191 return xfs_attr_rmtval_invalidate(args);
1192 }
1193
1194 return 0;
1195}
1196
1197STATIC int
1198xfs_attr_node_remove_rmt(
1199 struct xfs_da_args *args,
1200 struct xfs_da_state *state)
1201{
1202 int error = 0;
1203
1204 error = xfs_attr_rmtval_remove(args);
1205 if (error)
1206 return error;
1207
1208 /*
1209 * Refill the state structure with buffers, the prior calls released our
1210 * buffers.
1211 */
1212 return xfs_attr_refillstate(state);
1213}
1214
1215/*
1216 * Remove a name from a B-tree attribute list.
1217 *
1218 * This will involve walking down the Btree, and may involve joining
1219 * leaf nodes and even joining intermediate nodes up to and including
1220 * the root node (a special case of an intermediate node).
1221 */
1222STATIC int
1223xfs_attr_node_removename(
1224 struct xfs_da_args *args)
1225{
1226 struct xfs_da_state *state;
1227 struct xfs_da_state_blk *blk;
1228 int retval, error;
1229 struct xfs_inode *dp = args->dp;
1230
1231 trace_xfs_attr_node_removename(args);
1232
1233 error = xfs_attr_node_removename_setup(args, &state);
1234 if (error)
1235 goto out;
1236
1237 /*
1238 * If there is an out-of-line value, de-allocate the blocks.
1239 * This is done before we remove the attribute so that we don't
1240 * overflow the maximum size of a transaction and/or hit a deadlock.
1241 */
1242 if (args->rmtblkno > 0) {
1243 error = xfs_attr_node_remove_rmt(args, state);
1244 if (error)
1245 goto out;
1246 }
1247
1248 /*
1249 * Remove the name and update the hashvals in the tree.
1250 */
1251 blk = &state->path.blk[ state->path.active-1 ];
1252 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1253 retval = xfs_attr3_leaf_remove(blk->bp, args);
1254 xfs_da3_fixhashpath(state, &state->path);
1255
1256 /*
1257 * Check to see if the tree needs to be collapsed.
1258 */
1259 if (retval && (state->path.active > 1)) {
1260 error = xfs_da3_join(state);
1261 if (error)
1262 goto out;
1263 error = xfs_defer_finish(&args->trans);
1264 if (error)
1265 goto out;
1266 /*
1267 * Commit the Btree join operation and start a new trans.
1268 */
1269 error = xfs_trans_roll_inode(&args->trans, dp);
1270 if (error)
1271 goto out;
1272 }
1273
1274 /*
1275 * If the result is small enough, push it all into the inode.
1276 */
1277 if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
1278 error = xfs_attr_node_shrink(args, state);
1279
1280out:
1281 if (state)
1282 xfs_da_state_free(state);
1283 return error;
1284}
1285
1286/*
1287 * Fill in the disk block numbers in the state structure for the buffers
1288 * that are attached to the state structure.
1289 * This is done so that we can quickly reattach ourselves to those buffers
1290 * after some set of transaction commits have released these buffers.
1291 */
1292STATIC int
1293xfs_attr_fillstate(xfs_da_state_t *state)
1294{
1295 xfs_da_state_path_t *path;
1296 xfs_da_state_blk_t *blk;
1297 int level;
1298
1299 trace_xfs_attr_fillstate(state->args);
1300
1301 /*
1302 * Roll down the "path" in the state structure, storing the on-disk
1303 * block number for those buffers in the "path".
1304 */
1305 path = &state->path;
1306 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1307 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1308 if (blk->bp) {
1309 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1310 blk->bp = NULL;
1311 } else {
1312 blk->disk_blkno = 0;
1313 }
1314 }
1315
1316 /*
1317 * Roll down the "altpath" in the state structure, storing the on-disk
1318 * block number for those buffers in the "altpath".
1319 */
1320 path = &state->altpath;
1321 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1322 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1323 if (blk->bp) {
1324 blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1325 blk->bp = NULL;
1326 } else {
1327 blk->disk_blkno = 0;
1328 }
1329 }
1330
1331 return 0;
1332}
1333
1334/*
1335 * Reattach the buffers to the state structure based on the disk block
1336 * numbers stored in the state structure.
1337 * This is done after some set of transaction commits have released those
1338 * buffers from our grip.
1339 */
1340STATIC int
1341xfs_attr_refillstate(xfs_da_state_t *state)
1342{
1343 xfs_da_state_path_t *path;
1344 xfs_da_state_blk_t *blk;
1345 int level, error;
1346
1347 trace_xfs_attr_refillstate(state->args);
1348
1349 /*
1350 * Roll down the "path" in the state structure, storing the on-disk
1351 * block number for those buffers in the "path".
1352 */
1353 path = &state->path;
1354 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1355 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1356 if (blk->disk_blkno) {
1357 error = xfs_da3_node_read_mapped(state->args->trans,
1358 state->args->dp, blk->disk_blkno,
1359 &blk->bp, XFS_ATTR_FORK);
1360 if (error)
1361 return error;
1362 } else {
1363 blk->bp = NULL;
1364 }
1365 }
1366
1367 /*
1368 * Roll down the "altpath" in the state structure, storing the on-disk
1369 * block number for those buffers in the "altpath".
1370 */
1371 path = &state->altpath;
1372 ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1373 for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1374 if (blk->disk_blkno) {
1375 error = xfs_da3_node_read_mapped(state->args->trans,
1376 state->args->dp, blk->disk_blkno,
1377 &blk->bp, XFS_ATTR_FORK);
1378 if (error)
1379 return error;
1380 } else {
1381 blk->bp = NULL;
1382 }
1383 }
1384
1385 return 0;
1386}
1387
1388/*
1389 * Retrieve the attribute data from a node attribute list.
1390 *
1391 * This routine gets called for any attribute fork that has more than one
1392 * block, ie: both true Btree attr lists and for single-leaf-blocks with
1393 * "remote" values taking up more blocks.
1394 *
1395 * Returns 0 on successful retrieval, otherwise an error.
1396 */
1397STATIC int
1398xfs_attr_node_get(
1399 struct xfs_da_args *args)
1400{
1401 struct xfs_da_state *state;
1402 struct xfs_da_state_blk *blk;
1403 int i;
1404 int error;
1405
1406 trace_xfs_attr_node_get(args);
1407
1408 /*
1409 * Search to see if name exists, and get back a pointer to it.
1410 */
1411 error = xfs_attr_node_hasname(args, &state);
1412 if (error != -EEXIST)
1413 goto out_release;
1414
1415 /*
1416 * Get the value, local or "remote"
1417 */
1418 blk = &state->path.blk[state->path.active - 1];
1419 error = xfs_attr3_leaf_getvalue(blk->bp, args);
1420
1421 /*
1422 * If not in a transaction, we have to release all the buffers.
1423 */
1424out_release:
1425 for (i = 0; state != NULL && i < state->path.active; i++) {
1426 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1427 state->path.blk[i].bp = NULL;
1428 }
1429
1430 if (state)
1431 xfs_da_state_free(state);
1432 return error;
1433}
1434
1435/* Returns true if the attribute entry name is valid. */
1436bool
1437xfs_attr_namecheck(
1438 const void *name,
1439 size_t length)
1440{
1441 /*
1442 * MAXNAMELEN includes the trailing null, but (name/length) leave it
1443 * out, so use >= for the length check.
1444 */
1445 if (length >= MAXNAMELEN)
1446 return false;
1447
1448 /* There shouldn't be any nulls here */
1449 return !memchr(name, 0, length);
1450}