xref: /linux/fs/xfs/libxfs/xfs_attr.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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_da_format.h"
27 #include "xfs_da_btree.h"
28 #include "xfs_attr_sf.h"
29 #include "xfs_inode.h"
30 #include "xfs_alloc.h"
31 #include "xfs_trans.h"
32 #include "xfs_inode_item.h"
33 #include "xfs_bmap.h"
34 #include "xfs_bmap_util.h"
35 #include "xfs_bmap_btree.h"
36 #include "xfs_attr.h"
37 #include "xfs_attr_leaf.h"
38 #include "xfs_attr_remote.h"
39 #include "xfs_error.h"
40 #include "xfs_quota.h"
41 #include "xfs_trans_space.h"
42 #include "xfs_trace.h"
43 
44 /*
45  * xfs_attr.c
46  *
47  * Provide the external interfaces to manage attribute lists.
48  */
49 
50 /*========================================================================
51  * Function prototypes for the kernel.
52  *========================================================================*/
53 
54 /*
55  * Internal routines when attribute list fits inside the inode.
56  */
57 STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
58 
59 /*
60  * Internal routines when attribute list is one block.
61  */
62 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
63 STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args);
64 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
65 
66 /*
67  * Internal routines when attribute list is more than one block.
68  */
69 STATIC int xfs_attr_node_get(xfs_da_args_t *args);
70 STATIC int xfs_attr_node_addname(xfs_da_args_t *args);
71 STATIC int xfs_attr_node_removename(xfs_da_args_t *args);
72 STATIC int xfs_attr_fillstate(xfs_da_state_t *state);
73 STATIC int xfs_attr_refillstate(xfs_da_state_t *state);
74 
75 
76 STATIC int
77 xfs_attr_args_init(
78 	struct xfs_da_args	*args,
79 	struct xfs_inode	*dp,
80 	const unsigned char	*name,
81 	int			flags)
82 {
83 
84 	if (!name)
85 		return -EINVAL;
86 
87 	memset(args, 0, sizeof(*args));
88 	args->geo = dp->i_mount->m_attr_geo;
89 	args->whichfork = XFS_ATTR_FORK;
90 	args->dp = dp;
91 	args->flags = flags;
92 	args->name = name;
93 	args->namelen = strlen((const char *)name);
94 	if (args->namelen >= MAXNAMELEN)
95 		return -EFAULT;		/* match IRIX behaviour */
96 
97 	args->hashval = xfs_da_hashname(args->name, args->namelen);
98 	return 0;
99 }
100 
101 int
102 xfs_inode_hasattr(
103 	struct xfs_inode	*ip)
104 {
105 	if (!XFS_IFORK_Q(ip) ||
106 	    (ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
107 	     ip->i_d.di_anextents == 0))
108 		return 0;
109 	return 1;
110 }
111 
112 /*========================================================================
113  * Overall external interface routines.
114  *========================================================================*/
115 
116 int
117 xfs_attr_get(
118 	struct xfs_inode	*ip,
119 	const unsigned char	*name,
120 	unsigned char		*value,
121 	int			*valuelenp,
122 	int			flags)
123 {
124 	struct xfs_da_args	args;
125 	uint			lock_mode;
126 	int			error;
127 
128 	XFS_STATS_INC(xs_attr_get);
129 
130 	if (XFS_FORCED_SHUTDOWN(ip->i_mount))
131 		return -EIO;
132 
133 	if (!xfs_inode_hasattr(ip))
134 		return -ENOATTR;
135 
136 	error = xfs_attr_args_init(&args, ip, name, flags);
137 	if (error)
138 		return error;
139 
140 	args.value = value;
141 	args.valuelen = *valuelenp;
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
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
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_bmap_free	flist;
205 	struct xfs_trans_res	tres;
206 	xfs_fsblock_t		firstblock;
207 	int			rsvd = (flags & ATTR_ROOT) != 0;
208 	int			error, err2, committed, local;
209 
210 	XFS_STATS_INC(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.flist = &flist;
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 	/*
244 	 * Start our first transaction of the day.
245 	 *
246 	 * All future transactions during this code must be "chained" off
247 	 * this one via the trans_dup() call.  All transactions will contain
248 	 * the inode, and the inode will always be marked with trans_ihold().
249 	 * Since the inode will be locked in all transactions, we must log
250 	 * the inode in every transaction to let it float upward through
251 	 * the log.
252 	 */
253 	args.trans = xfs_trans_alloc(mp, XFS_TRANS_ATTR_SET);
254 
255 	/*
256 	 * Root fork attributes can use reserved data blocks for this
257 	 * operation if necessary
258 	 */
259 
260 	if (rsvd)
261 		args.trans->t_flags |= XFS_TRANS_RESERVE;
262 
263 	tres.tr_logres = M_RES(mp)->tr_attrsetm.tr_logres +
264 			 M_RES(mp)->tr_attrsetrt.tr_logres * args.total;
265 	tres.tr_logcount = XFS_ATTRSET_LOG_COUNT;
266 	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
267 	error = xfs_trans_reserve(args.trans, &tres, args.total, 0);
268 	if (error) {
269 		xfs_trans_cancel(args.trans, 0);
270 		return error;
271 	}
272 	xfs_ilock(dp, XFS_ILOCK_EXCL);
273 
274 	error = xfs_trans_reserve_quota_nblks(args.trans, dp, args.total, 0,
275 				rsvd ? XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
276 				       XFS_QMOPT_RES_REGBLKS);
277 	if (error) {
278 		xfs_iunlock(dp, XFS_ILOCK_EXCL);
279 		xfs_trans_cancel(args.trans, XFS_TRANS_RELEASE_LOG_RES);
280 		return error;
281 	}
282 
283 	xfs_trans_ijoin(args.trans, dp, 0);
284 
285 	/*
286 	 * If the attribute list is non-existent or a shortform list,
287 	 * upgrade it to a single-leaf-block attribute list.
288 	 */
289 	if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
290 	    (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
291 	     dp->i_d.di_anextents == 0)) {
292 
293 		/*
294 		 * Build initial attribute list (if required).
295 		 */
296 		if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS)
297 			xfs_attr_shortform_create(&args);
298 
299 		/*
300 		 * Try to add the attr to the attribute list in
301 		 * the inode.
302 		 */
303 		error = xfs_attr_shortform_addname(&args);
304 		if (error != -ENOSPC) {
305 			/*
306 			 * Commit the shortform mods, and we're done.
307 			 * NOTE: this is also the error path (EEXIST, etc).
308 			 */
309 			ASSERT(args.trans != NULL);
310 
311 			/*
312 			 * If this is a synchronous mount, make sure that
313 			 * the transaction goes to disk before returning
314 			 * to the user.
315 			 */
316 			if (mp->m_flags & XFS_MOUNT_WSYNC)
317 				xfs_trans_set_sync(args.trans);
318 
319 			if (!error && (flags & ATTR_KERNOTIME) == 0) {
320 				xfs_trans_ichgtime(args.trans, dp,
321 							XFS_ICHGTIME_CHG);
322 			}
323 			err2 = xfs_trans_commit(args.trans,
324 						 XFS_TRANS_RELEASE_LOG_RES);
325 			xfs_iunlock(dp, XFS_ILOCK_EXCL);
326 
327 			return error ? error : err2;
328 		}
329 
330 		/*
331 		 * It won't fit in the shortform, transform to a leaf block.
332 		 * GROT: another possible req'mt for a double-split btree op.
333 		 */
334 		xfs_bmap_init(args.flist, args.firstblock);
335 		error = xfs_attr_shortform_to_leaf(&args);
336 		if (!error) {
337 			error = xfs_bmap_finish(&args.trans, args.flist,
338 						&committed);
339 		}
340 		if (error) {
341 			ASSERT(committed);
342 			args.trans = NULL;
343 			xfs_bmap_cancel(&flist);
344 			goto out;
345 		}
346 
347 		/*
348 		 * bmap_finish() may have committed the last trans and started
349 		 * a new one.  We need the inode to be in all transactions.
350 		 */
351 		if (committed)
352 			xfs_trans_ijoin(args.trans, dp, 0);
353 
354 		/*
355 		 * Commit the leaf transformation.  We'll need another (linked)
356 		 * transaction to add the new attribute to the leaf.
357 		 */
358 
359 		error = xfs_trans_roll(&args.trans, dp);
360 		if (error)
361 			goto out;
362 
363 	}
364 
365 	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
366 		error = xfs_attr_leaf_addname(&args);
367 	else
368 		error = xfs_attr_node_addname(&args);
369 	if (error)
370 		goto out;
371 
372 	/*
373 	 * If this is a synchronous mount, make sure that the
374 	 * transaction goes to disk before returning to the user.
375 	 */
376 	if (mp->m_flags & XFS_MOUNT_WSYNC)
377 		xfs_trans_set_sync(args.trans);
378 
379 	if ((flags & ATTR_KERNOTIME) == 0)
380 		xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
381 
382 	/*
383 	 * Commit the last in the sequence of transactions.
384 	 */
385 	xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
386 	error = xfs_trans_commit(args.trans, XFS_TRANS_RELEASE_LOG_RES);
387 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
388 
389 	return error;
390 
391 out:
392 	if (args.trans) {
393 		xfs_trans_cancel(args.trans,
394 			XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
395 	}
396 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
397 	return error;
398 }
399 
400 /*
401  * Generic handler routine to remove a name from an attribute list.
402  * Transitions attribute list from Btree to shortform as necessary.
403  */
404 int
405 xfs_attr_remove(
406 	struct xfs_inode	*dp,
407 	const unsigned char	*name,
408 	int			flags)
409 {
410 	struct xfs_mount	*mp = dp->i_mount;
411 	struct xfs_da_args	args;
412 	struct xfs_bmap_free	flist;
413 	xfs_fsblock_t		firstblock;
414 	int			error;
415 
416 	XFS_STATS_INC(xs_attr_remove);
417 
418 	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
419 		return -EIO;
420 
421 	if (!xfs_inode_hasattr(dp))
422 		return -ENOATTR;
423 
424 	error = xfs_attr_args_init(&args, dp, name, flags);
425 	if (error)
426 		return error;
427 
428 	args.firstblock = &firstblock;
429 	args.flist = &flist;
430 
431 	/*
432 	 * we have no control over the attribute names that userspace passes us
433 	 * to remove, so we have to allow the name lookup prior to attribute
434 	 * removal to fail.
435 	 */
436 	args.op_flags = XFS_DA_OP_OKNOENT;
437 
438 	error = xfs_qm_dqattach(dp, 0);
439 	if (error)
440 		return error;
441 
442 	/*
443 	 * Start our first transaction of the day.
444 	 *
445 	 * All future transactions during this code must be "chained" off
446 	 * this one via the trans_dup() call.  All transactions will contain
447 	 * the inode, and the inode will always be marked with trans_ihold().
448 	 * Since the inode will be locked in all transactions, we must log
449 	 * the inode in every transaction to let it float upward through
450 	 * the log.
451 	 */
452 	args.trans = xfs_trans_alloc(mp, XFS_TRANS_ATTR_RM);
453 
454 	/*
455 	 * Root fork attributes can use reserved data blocks for this
456 	 * operation if necessary
457 	 */
458 
459 	if (flags & ATTR_ROOT)
460 		args.trans->t_flags |= XFS_TRANS_RESERVE;
461 
462 	error = xfs_trans_reserve(args.trans, &M_RES(mp)->tr_attrrm,
463 				  XFS_ATTRRM_SPACE_RES(mp), 0);
464 	if (error) {
465 		xfs_trans_cancel(args.trans, 0);
466 		return error;
467 	}
468 
469 	xfs_ilock(dp, XFS_ILOCK_EXCL);
470 	/*
471 	 * No need to make quota reservations here. We expect to release some
472 	 * blocks not allocate in the common case.
473 	 */
474 	xfs_trans_ijoin(args.trans, dp, 0);
475 
476 	if (!xfs_inode_hasattr(dp)) {
477 		error = -ENOATTR;
478 	} else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
479 		ASSERT(dp->i_afp->if_flags & XFS_IFINLINE);
480 		error = xfs_attr_shortform_remove(&args);
481 	} else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
482 		error = xfs_attr_leaf_removename(&args);
483 	} else {
484 		error = xfs_attr_node_removename(&args);
485 	}
486 
487 	if (error)
488 		goto out;
489 
490 	/*
491 	 * If this is a synchronous mount, make sure that the
492 	 * transaction goes to disk before returning to the user.
493 	 */
494 	if (mp->m_flags & XFS_MOUNT_WSYNC)
495 		xfs_trans_set_sync(args.trans);
496 
497 	if ((flags & ATTR_KERNOTIME) == 0)
498 		xfs_trans_ichgtime(args.trans, dp, XFS_ICHGTIME_CHG);
499 
500 	/*
501 	 * Commit the last in the sequence of transactions.
502 	 */
503 	xfs_trans_log_inode(args.trans, dp, XFS_ILOG_CORE);
504 	error = xfs_trans_commit(args.trans, XFS_TRANS_RELEASE_LOG_RES);
505 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
506 
507 	return error;
508 
509 out:
510 	if (args.trans) {
511 		xfs_trans_cancel(args.trans,
512 			XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
513 	}
514 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
515 	return error;
516 }
517 
518 /*========================================================================
519  * External routines when attribute list is inside the inode
520  *========================================================================*/
521 
522 /*
523  * Add a name to the shortform attribute list structure
524  * This is the external routine.
525  */
526 STATIC int
527 xfs_attr_shortform_addname(xfs_da_args_t *args)
528 {
529 	int newsize, forkoff, retval;
530 
531 	trace_xfs_attr_sf_addname(args);
532 
533 	retval = xfs_attr_shortform_lookup(args);
534 	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
535 		return retval;
536 	} else if (retval == -EEXIST) {
537 		if (args->flags & ATTR_CREATE)
538 			return retval;
539 		retval = xfs_attr_shortform_remove(args);
540 		ASSERT(retval == 0);
541 	}
542 
543 	if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX ||
544 	    args->valuelen >= XFS_ATTR_SF_ENTSIZE_MAX)
545 		return -ENOSPC;
546 
547 	newsize = XFS_ATTR_SF_TOTSIZE(args->dp);
548 	newsize += XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
549 
550 	forkoff = xfs_attr_shortform_bytesfit(args->dp, newsize);
551 	if (!forkoff)
552 		return -ENOSPC;
553 
554 	xfs_attr_shortform_add(args, forkoff);
555 	return 0;
556 }
557 
558 
559 /*========================================================================
560  * External routines when attribute list is one block
561  *========================================================================*/
562 
563 /*
564  * Add a name to the leaf attribute list structure
565  *
566  * This leaf block cannot have a "remote" value, we only call this routine
567  * if bmap_one_block() says there is only one block (ie: no remote blks).
568  */
569 STATIC int
570 xfs_attr_leaf_addname(xfs_da_args_t *args)
571 {
572 	xfs_inode_t *dp;
573 	struct xfs_buf *bp;
574 	int retval, error, committed, forkoff;
575 
576 	trace_xfs_attr_leaf_addname(args);
577 
578 	/*
579 	 * Read the (only) block in the attribute list in.
580 	 */
581 	dp = args->dp;
582 	args->blkno = 0;
583 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
584 	if (error)
585 		return error;
586 
587 	/*
588 	 * Look up the given attribute in the leaf block.  Figure out if
589 	 * the given flags produce an error or call for an atomic rename.
590 	 */
591 	retval = xfs_attr3_leaf_lookup_int(bp, args);
592 	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
593 		xfs_trans_brelse(args->trans, bp);
594 		return retval;
595 	} else if (retval == -EEXIST) {
596 		if (args->flags & ATTR_CREATE) {	/* pure create op */
597 			xfs_trans_brelse(args->trans, bp);
598 			return retval;
599 		}
600 
601 		trace_xfs_attr_leaf_replace(args);
602 
603 		/* save the attribute state for later removal*/
604 		args->op_flags |= XFS_DA_OP_RENAME;	/* an atomic rename */
605 		args->blkno2 = args->blkno;		/* set 2nd entry info*/
606 		args->index2 = args->index;
607 		args->rmtblkno2 = args->rmtblkno;
608 		args->rmtblkcnt2 = args->rmtblkcnt;
609 		args->rmtvaluelen2 = args->rmtvaluelen;
610 
611 		/*
612 		 * clear the remote attr state now that it is saved so that the
613 		 * values reflect the state of the attribute we are about to
614 		 * add, not the attribute we just found and will remove later.
615 		 */
616 		args->rmtblkno = 0;
617 		args->rmtblkcnt = 0;
618 		args->rmtvaluelen = 0;
619 	}
620 
621 	/*
622 	 * Add the attribute to the leaf block, transitioning to a Btree
623 	 * if required.
624 	 */
625 	retval = xfs_attr3_leaf_add(bp, args);
626 	if (retval == -ENOSPC) {
627 		/*
628 		 * Promote the attribute list to the Btree format, then
629 		 * Commit that transaction so that the node_addname() call
630 		 * can manage its own transactions.
631 		 */
632 		xfs_bmap_init(args->flist, args->firstblock);
633 		error = xfs_attr3_leaf_to_node(args);
634 		if (!error) {
635 			error = xfs_bmap_finish(&args->trans, args->flist,
636 						&committed);
637 		}
638 		if (error) {
639 			ASSERT(committed);
640 			args->trans = NULL;
641 			xfs_bmap_cancel(args->flist);
642 			return error;
643 		}
644 
645 		/*
646 		 * bmap_finish() may have committed the last trans and started
647 		 * a new one.  We need the inode to be in all transactions.
648 		 */
649 		if (committed)
650 			xfs_trans_ijoin(args->trans, dp, 0);
651 
652 		/*
653 		 * Commit the current trans (including the inode) and start
654 		 * a new one.
655 		 */
656 		error = xfs_trans_roll(&args->trans, dp);
657 		if (error)
658 			return error;
659 
660 		/*
661 		 * Fob the whole rest of the problem off on the Btree code.
662 		 */
663 		error = xfs_attr_node_addname(args);
664 		return error;
665 	}
666 
667 	/*
668 	 * Commit the transaction that added the attr name so that
669 	 * later routines can manage their own transactions.
670 	 */
671 	error = xfs_trans_roll(&args->trans, dp);
672 	if (error)
673 		return error;
674 
675 	/*
676 	 * If there was an out-of-line value, allocate the blocks we
677 	 * identified for its storage and copy the value.  This is done
678 	 * after we create the attribute so that we don't overflow the
679 	 * maximum size of a transaction and/or hit a deadlock.
680 	 */
681 	if (args->rmtblkno > 0) {
682 		error = xfs_attr_rmtval_set(args);
683 		if (error)
684 			return error;
685 	}
686 
687 	/*
688 	 * If this is an atomic rename operation, we must "flip" the
689 	 * incomplete flags on the "new" and "old" attribute/value pairs
690 	 * so that one disappears and one appears atomically.  Then we
691 	 * must remove the "old" attribute/value pair.
692 	 */
693 	if (args->op_flags & XFS_DA_OP_RENAME) {
694 		/*
695 		 * In a separate transaction, set the incomplete flag on the
696 		 * "old" attr and clear the incomplete flag on the "new" attr.
697 		 */
698 		error = xfs_attr3_leaf_flipflags(args);
699 		if (error)
700 			return error;
701 
702 		/*
703 		 * Dismantle the "old" attribute/value pair by removing
704 		 * a "remote" value (if it exists).
705 		 */
706 		args->index = args->index2;
707 		args->blkno = args->blkno2;
708 		args->rmtblkno = args->rmtblkno2;
709 		args->rmtblkcnt = args->rmtblkcnt2;
710 		args->rmtvaluelen = args->rmtvaluelen2;
711 		if (args->rmtblkno) {
712 			error = xfs_attr_rmtval_remove(args);
713 			if (error)
714 				return error;
715 		}
716 
717 		/*
718 		 * Read in the block containing the "old" attr, then
719 		 * remove the "old" attr from that block (neat, huh!)
720 		 */
721 		error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
722 					   -1, &bp);
723 		if (error)
724 			return error;
725 
726 		xfs_attr3_leaf_remove(bp, args);
727 
728 		/*
729 		 * If the result is small enough, shrink it all into the inode.
730 		 */
731 		if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
732 			xfs_bmap_init(args->flist, args->firstblock);
733 			error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
734 			/* bp is gone due to xfs_da_shrink_inode */
735 			if (!error) {
736 				error = xfs_bmap_finish(&args->trans,
737 							args->flist,
738 							&committed);
739 			}
740 			if (error) {
741 				ASSERT(committed);
742 				args->trans = NULL;
743 				xfs_bmap_cancel(args->flist);
744 				return error;
745 			}
746 
747 			/*
748 			 * bmap_finish() may have committed the last trans
749 			 * and started a new one.  We need the inode to be
750 			 * in all transactions.
751 			 */
752 			if (committed)
753 				xfs_trans_ijoin(args->trans, dp, 0);
754 		}
755 
756 		/*
757 		 * Commit the remove and start the next trans in series.
758 		 */
759 		error = xfs_trans_roll(&args->trans, dp);
760 
761 	} else if (args->rmtblkno > 0) {
762 		/*
763 		 * Added a "remote" value, just clear the incomplete flag.
764 		 */
765 		error = xfs_attr3_leaf_clearflag(args);
766 	}
767 	return error;
768 }
769 
770 /*
771  * Remove a name from the leaf attribute list structure
772  *
773  * This leaf block cannot have a "remote" value, we only call this routine
774  * if bmap_one_block() says there is only one block (ie: no remote blks).
775  */
776 STATIC int
777 xfs_attr_leaf_removename(xfs_da_args_t *args)
778 {
779 	xfs_inode_t *dp;
780 	struct xfs_buf *bp;
781 	int error, committed, forkoff;
782 
783 	trace_xfs_attr_leaf_removename(args);
784 
785 	/*
786 	 * Remove the attribute.
787 	 */
788 	dp = args->dp;
789 	args->blkno = 0;
790 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
791 	if (error)
792 		return error;
793 
794 	error = xfs_attr3_leaf_lookup_int(bp, args);
795 	if (error == -ENOATTR) {
796 		xfs_trans_brelse(args->trans, bp);
797 		return error;
798 	}
799 
800 	xfs_attr3_leaf_remove(bp, args);
801 
802 	/*
803 	 * If the result is small enough, shrink it all into the inode.
804 	 */
805 	if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
806 		xfs_bmap_init(args->flist, args->firstblock);
807 		error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
808 		/* bp is gone due to xfs_da_shrink_inode */
809 		if (!error) {
810 			error = xfs_bmap_finish(&args->trans, args->flist,
811 						&committed);
812 		}
813 		if (error) {
814 			ASSERT(committed);
815 			args->trans = NULL;
816 			xfs_bmap_cancel(args->flist);
817 			return error;
818 		}
819 
820 		/*
821 		 * bmap_finish() may have committed the last trans and started
822 		 * a new one.  We need the inode to be in all transactions.
823 		 */
824 		if (committed)
825 			xfs_trans_ijoin(args->trans, dp, 0);
826 	}
827 	return 0;
828 }
829 
830 /*
831  * Look up a name in a leaf attribute list structure.
832  *
833  * This leaf block cannot have a "remote" value, we only call this routine
834  * if bmap_one_block() says there is only one block (ie: no remote blks).
835  */
836 STATIC int
837 xfs_attr_leaf_get(xfs_da_args_t *args)
838 {
839 	struct xfs_buf *bp;
840 	int error;
841 
842 	trace_xfs_attr_leaf_get(args);
843 
844 	args->blkno = 0;
845 	error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
846 	if (error)
847 		return error;
848 
849 	error = xfs_attr3_leaf_lookup_int(bp, args);
850 	if (error != -EEXIST)  {
851 		xfs_trans_brelse(args->trans, bp);
852 		return error;
853 	}
854 	error = xfs_attr3_leaf_getvalue(bp, args);
855 	xfs_trans_brelse(args->trans, bp);
856 	if (!error && (args->rmtblkno > 0) && !(args->flags & ATTR_KERNOVAL)) {
857 		error = xfs_attr_rmtval_get(args);
858 	}
859 	return error;
860 }
861 
862 /*========================================================================
863  * External routines when attribute list size > geo->blksize
864  *========================================================================*/
865 
866 /*
867  * Add a name to a Btree-format attribute list.
868  *
869  * This will involve walking down the Btree, and may involve splitting
870  * leaf nodes and even splitting intermediate nodes up to and including
871  * the root node (a special case of an intermediate node).
872  *
873  * "Remote" attribute values confuse the issue and atomic rename operations
874  * add a whole extra layer of confusion on top of that.
875  */
876 STATIC int
877 xfs_attr_node_addname(xfs_da_args_t *args)
878 {
879 	xfs_da_state_t *state;
880 	xfs_da_state_blk_t *blk;
881 	xfs_inode_t *dp;
882 	xfs_mount_t *mp;
883 	int committed, retval, error;
884 
885 	trace_xfs_attr_node_addname(args);
886 
887 	/*
888 	 * Fill in bucket of arguments/results/context to carry around.
889 	 */
890 	dp = args->dp;
891 	mp = dp->i_mount;
892 restart:
893 	state = xfs_da_state_alloc();
894 	state->args = args;
895 	state->mp = mp;
896 
897 	/*
898 	 * Search to see if name already exists, and get back a pointer
899 	 * to where it should go.
900 	 */
901 	error = xfs_da3_node_lookup_int(state, &retval);
902 	if (error)
903 		goto out;
904 	blk = &state->path.blk[ state->path.active-1 ];
905 	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
906 	if ((args->flags & ATTR_REPLACE) && (retval == -ENOATTR)) {
907 		goto out;
908 	} else if (retval == -EEXIST) {
909 		if (args->flags & ATTR_CREATE)
910 			goto out;
911 
912 		trace_xfs_attr_node_replace(args);
913 
914 		/* save the attribute state for later removal*/
915 		args->op_flags |= XFS_DA_OP_RENAME;	/* atomic rename op */
916 		args->blkno2 = args->blkno;		/* set 2nd entry info*/
917 		args->index2 = args->index;
918 		args->rmtblkno2 = args->rmtblkno;
919 		args->rmtblkcnt2 = args->rmtblkcnt;
920 		args->rmtvaluelen2 = args->rmtvaluelen;
921 
922 		/*
923 		 * clear the remote attr state now that it is saved so that the
924 		 * values reflect the state of the attribute we are about to
925 		 * add, not the attribute we just found and will remove later.
926 		 */
927 		args->rmtblkno = 0;
928 		args->rmtblkcnt = 0;
929 		args->rmtvaluelen = 0;
930 	}
931 
932 	retval = xfs_attr3_leaf_add(blk->bp, state->args);
933 	if (retval == -ENOSPC) {
934 		if (state->path.active == 1) {
935 			/*
936 			 * Its really a single leaf node, but it had
937 			 * out-of-line values so it looked like it *might*
938 			 * have been a b-tree.
939 			 */
940 			xfs_da_state_free(state);
941 			state = NULL;
942 			xfs_bmap_init(args->flist, args->firstblock);
943 			error = xfs_attr3_leaf_to_node(args);
944 			if (!error) {
945 				error = xfs_bmap_finish(&args->trans,
946 							args->flist,
947 							&committed);
948 			}
949 			if (error) {
950 				ASSERT(committed);
951 				args->trans = NULL;
952 				xfs_bmap_cancel(args->flist);
953 				goto out;
954 			}
955 
956 			/*
957 			 * bmap_finish() may have committed the last trans
958 			 * and started a new one.  We need the inode to be
959 			 * in all transactions.
960 			 */
961 			if (committed)
962 				xfs_trans_ijoin(args->trans, dp, 0);
963 
964 			/*
965 			 * Commit the node conversion and start the next
966 			 * trans in the chain.
967 			 */
968 			error = xfs_trans_roll(&args->trans, dp);
969 			if (error)
970 				goto out;
971 
972 			goto restart;
973 		}
974 
975 		/*
976 		 * Split as many Btree elements as required.
977 		 * This code tracks the new and old attr's location
978 		 * in the index/blkno/rmtblkno/rmtblkcnt fields and
979 		 * in the index2/blkno2/rmtblkno2/rmtblkcnt2 fields.
980 		 */
981 		xfs_bmap_init(args->flist, args->firstblock);
982 		error = xfs_da3_split(state);
983 		if (!error) {
984 			error = xfs_bmap_finish(&args->trans, args->flist,
985 						&committed);
986 		}
987 		if (error) {
988 			ASSERT(committed);
989 			args->trans = NULL;
990 			xfs_bmap_cancel(args->flist);
991 			goto out;
992 		}
993 
994 		/*
995 		 * bmap_finish() may have committed the last trans and started
996 		 * a new one.  We need the inode to be in all transactions.
997 		 */
998 		if (committed)
999 			xfs_trans_ijoin(args->trans, dp, 0);
1000 	} else {
1001 		/*
1002 		 * Addition succeeded, update Btree hashvals.
1003 		 */
1004 		xfs_da3_fixhashpath(state, &state->path);
1005 	}
1006 
1007 	/*
1008 	 * Kill the state structure, we're done with it and need to
1009 	 * allow the buffers to come back later.
1010 	 */
1011 	xfs_da_state_free(state);
1012 	state = NULL;
1013 
1014 	/*
1015 	 * Commit the leaf addition or btree split and start the next
1016 	 * trans in the chain.
1017 	 */
1018 	error = xfs_trans_roll(&args->trans, dp);
1019 	if (error)
1020 		goto out;
1021 
1022 	/*
1023 	 * If there was an out-of-line value, allocate the blocks we
1024 	 * identified for its storage and copy the value.  This is done
1025 	 * after we create the attribute so that we don't overflow the
1026 	 * maximum size of a transaction and/or hit a deadlock.
1027 	 */
1028 	if (args->rmtblkno > 0) {
1029 		error = xfs_attr_rmtval_set(args);
1030 		if (error)
1031 			return error;
1032 	}
1033 
1034 	/*
1035 	 * If this is an atomic rename operation, we must "flip" the
1036 	 * incomplete flags on the "new" and "old" attribute/value pairs
1037 	 * so that one disappears and one appears atomically.  Then we
1038 	 * must remove the "old" attribute/value pair.
1039 	 */
1040 	if (args->op_flags & XFS_DA_OP_RENAME) {
1041 		/*
1042 		 * In a separate transaction, set the incomplete flag on the
1043 		 * "old" attr and clear the incomplete flag on the "new" attr.
1044 		 */
1045 		error = xfs_attr3_leaf_flipflags(args);
1046 		if (error)
1047 			goto out;
1048 
1049 		/*
1050 		 * Dismantle the "old" attribute/value pair by removing
1051 		 * a "remote" value (if it exists).
1052 		 */
1053 		args->index = args->index2;
1054 		args->blkno = args->blkno2;
1055 		args->rmtblkno = args->rmtblkno2;
1056 		args->rmtblkcnt = args->rmtblkcnt2;
1057 		args->rmtvaluelen = args->rmtvaluelen2;
1058 		if (args->rmtblkno) {
1059 			error = xfs_attr_rmtval_remove(args);
1060 			if (error)
1061 				return error;
1062 		}
1063 
1064 		/*
1065 		 * Re-find the "old" attribute entry after any split ops.
1066 		 * The INCOMPLETE flag means that we will find the "old"
1067 		 * attr, not the "new" one.
1068 		 */
1069 		args->flags |= XFS_ATTR_INCOMPLETE;
1070 		state = xfs_da_state_alloc();
1071 		state->args = args;
1072 		state->mp = mp;
1073 		state->inleaf = 0;
1074 		error = xfs_da3_node_lookup_int(state, &retval);
1075 		if (error)
1076 			goto out;
1077 
1078 		/*
1079 		 * Remove the name and update the hashvals in the tree.
1080 		 */
1081 		blk = &state->path.blk[ state->path.active-1 ];
1082 		ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1083 		error = xfs_attr3_leaf_remove(blk->bp, args);
1084 		xfs_da3_fixhashpath(state, &state->path);
1085 
1086 		/*
1087 		 * Check to see if the tree needs to be collapsed.
1088 		 */
1089 		if (retval && (state->path.active > 1)) {
1090 			xfs_bmap_init(args->flist, args->firstblock);
1091 			error = xfs_da3_join(state);
1092 			if (!error) {
1093 				error = xfs_bmap_finish(&args->trans,
1094 							args->flist,
1095 							&committed);
1096 			}
1097 			if (error) {
1098 				ASSERT(committed);
1099 				args->trans = NULL;
1100 				xfs_bmap_cancel(args->flist);
1101 				goto out;
1102 			}
1103 
1104 			/*
1105 			 * bmap_finish() may have committed the last trans
1106 			 * and started a new one.  We need the inode to be
1107 			 * in all transactions.
1108 			 */
1109 			if (committed)
1110 				xfs_trans_ijoin(args->trans, dp, 0);
1111 		}
1112 
1113 		/*
1114 		 * Commit and start the next trans in the chain.
1115 		 */
1116 		error = xfs_trans_roll(&args->trans, dp);
1117 		if (error)
1118 			goto out;
1119 
1120 	} else if (args->rmtblkno > 0) {
1121 		/*
1122 		 * Added a "remote" value, just clear the incomplete flag.
1123 		 */
1124 		error = xfs_attr3_leaf_clearflag(args);
1125 		if (error)
1126 			goto out;
1127 	}
1128 	retval = error = 0;
1129 
1130 out:
1131 	if (state)
1132 		xfs_da_state_free(state);
1133 	if (error)
1134 		return error;
1135 	return retval;
1136 }
1137 
1138 /*
1139  * Remove a name from a B-tree attribute list.
1140  *
1141  * This will involve walking down the Btree, and may involve joining
1142  * leaf nodes and even joining intermediate nodes up to and including
1143  * the root node (a special case of an intermediate node).
1144  */
1145 STATIC int
1146 xfs_attr_node_removename(xfs_da_args_t *args)
1147 {
1148 	xfs_da_state_t *state;
1149 	xfs_da_state_blk_t *blk;
1150 	xfs_inode_t *dp;
1151 	struct xfs_buf *bp;
1152 	int retval, error, committed, forkoff;
1153 
1154 	trace_xfs_attr_node_removename(args);
1155 
1156 	/*
1157 	 * Tie a string around our finger to remind us where we are.
1158 	 */
1159 	dp = args->dp;
1160 	state = xfs_da_state_alloc();
1161 	state->args = args;
1162 	state->mp = dp->i_mount;
1163 
1164 	/*
1165 	 * Search to see if name exists, and get back a pointer to it.
1166 	 */
1167 	error = xfs_da3_node_lookup_int(state, &retval);
1168 	if (error || (retval != -EEXIST)) {
1169 		if (error == 0)
1170 			error = retval;
1171 		goto out;
1172 	}
1173 
1174 	/*
1175 	 * If there is an out-of-line value, de-allocate the blocks.
1176 	 * This is done before we remove the attribute so that we don't
1177 	 * overflow the maximum size of a transaction and/or hit a deadlock.
1178 	 */
1179 	blk = &state->path.blk[ state->path.active-1 ];
1180 	ASSERT(blk->bp != NULL);
1181 	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1182 	if (args->rmtblkno > 0) {
1183 		/*
1184 		 * Fill in disk block numbers in the state structure
1185 		 * so that we can get the buffers back after we commit
1186 		 * several transactions in the following calls.
1187 		 */
1188 		error = xfs_attr_fillstate(state);
1189 		if (error)
1190 			goto out;
1191 
1192 		/*
1193 		 * Mark the attribute as INCOMPLETE, then bunmapi() the
1194 		 * remote value.
1195 		 */
1196 		error = xfs_attr3_leaf_setflag(args);
1197 		if (error)
1198 			goto out;
1199 		error = xfs_attr_rmtval_remove(args);
1200 		if (error)
1201 			goto out;
1202 
1203 		/*
1204 		 * Refill the state structure with buffers, the prior calls
1205 		 * released our buffers.
1206 		 */
1207 		error = xfs_attr_refillstate(state);
1208 		if (error)
1209 			goto out;
1210 	}
1211 
1212 	/*
1213 	 * Remove the name and update the hashvals in the tree.
1214 	 */
1215 	blk = &state->path.blk[ state->path.active-1 ];
1216 	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1217 	retval = xfs_attr3_leaf_remove(blk->bp, args);
1218 	xfs_da3_fixhashpath(state, &state->path);
1219 
1220 	/*
1221 	 * Check to see if the tree needs to be collapsed.
1222 	 */
1223 	if (retval && (state->path.active > 1)) {
1224 		xfs_bmap_init(args->flist, args->firstblock);
1225 		error = xfs_da3_join(state);
1226 		if (!error) {
1227 			error = xfs_bmap_finish(&args->trans, args->flist,
1228 						&committed);
1229 		}
1230 		if (error) {
1231 			ASSERT(committed);
1232 			args->trans = NULL;
1233 			xfs_bmap_cancel(args->flist);
1234 			goto out;
1235 		}
1236 
1237 		/*
1238 		 * bmap_finish() may have committed the last trans and started
1239 		 * a new one.  We need the inode to be in all transactions.
1240 		 */
1241 		if (committed)
1242 			xfs_trans_ijoin(args->trans, dp, 0);
1243 
1244 		/*
1245 		 * Commit the Btree join operation and start a new trans.
1246 		 */
1247 		error = xfs_trans_roll(&args->trans, dp);
1248 		if (error)
1249 			goto out;
1250 	}
1251 
1252 	/*
1253 	 * If the result is small enough, push it all into the inode.
1254 	 */
1255 	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
1256 		/*
1257 		 * Have to get rid of the copy of this dabuf in the state.
1258 		 */
1259 		ASSERT(state->path.active == 1);
1260 		ASSERT(state->path.blk[0].bp);
1261 		state->path.blk[0].bp = NULL;
1262 
1263 		error = xfs_attr3_leaf_read(args->trans, args->dp, 0, -1, &bp);
1264 		if (error)
1265 			goto out;
1266 
1267 		if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
1268 			xfs_bmap_init(args->flist, args->firstblock);
1269 			error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
1270 			/* bp is gone due to xfs_da_shrink_inode */
1271 			if (!error) {
1272 				error = xfs_bmap_finish(&args->trans,
1273 							args->flist,
1274 							&committed);
1275 			}
1276 			if (error) {
1277 				ASSERT(committed);
1278 				args->trans = NULL;
1279 				xfs_bmap_cancel(args->flist);
1280 				goto out;
1281 			}
1282 
1283 			/*
1284 			 * bmap_finish() may have committed the last trans
1285 			 * and started a new one.  We need the inode to be
1286 			 * in all transactions.
1287 			 */
1288 			if (committed)
1289 				xfs_trans_ijoin(args->trans, dp, 0);
1290 		} else
1291 			xfs_trans_brelse(args->trans, bp);
1292 	}
1293 	error = 0;
1294 
1295 out:
1296 	xfs_da_state_free(state);
1297 	return error;
1298 }
1299 
1300 /*
1301  * Fill in the disk block numbers in the state structure for the buffers
1302  * that are attached to the state structure.
1303  * This is done so that we can quickly reattach ourselves to those buffers
1304  * after some set of transaction commits have released these buffers.
1305  */
1306 STATIC int
1307 xfs_attr_fillstate(xfs_da_state_t *state)
1308 {
1309 	xfs_da_state_path_t *path;
1310 	xfs_da_state_blk_t *blk;
1311 	int level;
1312 
1313 	trace_xfs_attr_fillstate(state->args);
1314 
1315 	/*
1316 	 * Roll down the "path" in the state structure, storing the on-disk
1317 	 * block number for those buffers in the "path".
1318 	 */
1319 	path = &state->path;
1320 	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1321 	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1322 		if (blk->bp) {
1323 			blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1324 			blk->bp = NULL;
1325 		} else {
1326 			blk->disk_blkno = 0;
1327 		}
1328 	}
1329 
1330 	/*
1331 	 * Roll down the "altpath" in the state structure, storing the on-disk
1332 	 * block number for those buffers in the "altpath".
1333 	 */
1334 	path = &state->altpath;
1335 	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1336 	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1337 		if (blk->bp) {
1338 			blk->disk_blkno = XFS_BUF_ADDR(blk->bp);
1339 			blk->bp = NULL;
1340 		} else {
1341 			blk->disk_blkno = 0;
1342 		}
1343 	}
1344 
1345 	return 0;
1346 }
1347 
1348 /*
1349  * Reattach the buffers to the state structure based on the disk block
1350  * numbers stored in the state structure.
1351  * This is done after some set of transaction commits have released those
1352  * buffers from our grip.
1353  */
1354 STATIC int
1355 xfs_attr_refillstate(xfs_da_state_t *state)
1356 {
1357 	xfs_da_state_path_t *path;
1358 	xfs_da_state_blk_t *blk;
1359 	int level, error;
1360 
1361 	trace_xfs_attr_refillstate(state->args);
1362 
1363 	/*
1364 	 * Roll down the "path" in the state structure, storing the on-disk
1365 	 * block number for those buffers in the "path".
1366 	 */
1367 	path = &state->path;
1368 	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1369 	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1370 		if (blk->disk_blkno) {
1371 			error = xfs_da3_node_read(state->args->trans,
1372 						state->args->dp,
1373 						blk->blkno, blk->disk_blkno,
1374 						&blk->bp, XFS_ATTR_FORK);
1375 			if (error)
1376 				return error;
1377 		} else {
1378 			blk->bp = NULL;
1379 		}
1380 	}
1381 
1382 	/*
1383 	 * Roll down the "altpath" in the state structure, storing the on-disk
1384 	 * block number for those buffers in the "altpath".
1385 	 */
1386 	path = &state->altpath;
1387 	ASSERT((path->active >= 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
1388 	for (blk = path->blk, level = 0; level < path->active; blk++, level++) {
1389 		if (blk->disk_blkno) {
1390 			error = xfs_da3_node_read(state->args->trans,
1391 						state->args->dp,
1392 						blk->blkno, blk->disk_blkno,
1393 						&blk->bp, XFS_ATTR_FORK);
1394 			if (error)
1395 				return error;
1396 		} else {
1397 			blk->bp = NULL;
1398 		}
1399 	}
1400 
1401 	return 0;
1402 }
1403 
1404 /*
1405  * Look up a filename in a node attribute list.
1406  *
1407  * This routine gets called for any attribute fork that has more than one
1408  * block, ie: both true Btree attr lists and for single-leaf-blocks with
1409  * "remote" values taking up more blocks.
1410  */
1411 STATIC int
1412 xfs_attr_node_get(xfs_da_args_t *args)
1413 {
1414 	xfs_da_state_t *state;
1415 	xfs_da_state_blk_t *blk;
1416 	int error, retval;
1417 	int i;
1418 
1419 	trace_xfs_attr_node_get(args);
1420 
1421 	state = xfs_da_state_alloc();
1422 	state->args = args;
1423 	state->mp = args->dp->i_mount;
1424 
1425 	/*
1426 	 * Search to see if name exists, and get back a pointer to it.
1427 	 */
1428 	error = xfs_da3_node_lookup_int(state, &retval);
1429 	if (error) {
1430 		retval = error;
1431 	} else if (retval == -EEXIST) {
1432 		blk = &state->path.blk[ state->path.active-1 ];
1433 		ASSERT(blk->bp != NULL);
1434 		ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
1435 
1436 		/*
1437 		 * Get the value, local or "remote"
1438 		 */
1439 		retval = xfs_attr3_leaf_getvalue(blk->bp, args);
1440 		if (!retval && (args->rmtblkno > 0)
1441 		    && !(args->flags & ATTR_KERNOVAL)) {
1442 			retval = xfs_attr_rmtval_get(args);
1443 		}
1444 	}
1445 
1446 	/*
1447 	 * If not in a transaction, we have to release all the buffers.
1448 	 */
1449 	for (i = 0; i < state->path.active; i++) {
1450 		xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1451 		state->path.blk[i].bp = NULL;
1452 	}
1453 
1454 	xfs_da_state_free(state);
1455 	return retval;
1456 }
1457