xref: /openbmc/linux/fs/xfs/xfs_itable.c (revision 239480ab)
1 /*
2  * Copyright (c) 2000-2002,2005 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_mount.h"
25 #include "xfs_inode.h"
26 #include "xfs_btree.h"
27 #include "xfs_ialloc.h"
28 #include "xfs_ialloc_btree.h"
29 #include "xfs_itable.h"
30 #include "xfs_error.h"
31 #include "xfs_trace.h"
32 #include "xfs_icache.h"
33 
34 STATIC int
35 xfs_internal_inum(
36 	xfs_mount_t	*mp,
37 	xfs_ino_t	ino)
38 {
39 	return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
40 		(xfs_sb_version_hasquota(&mp->m_sb) &&
41 		 xfs_is_quota_inode(&mp->m_sb, ino)));
42 }
43 
44 /*
45  * Return stat information for one inode.
46  * Return 0 if ok, else errno.
47  */
48 int
49 xfs_bulkstat_one_int(
50 	struct xfs_mount	*mp,		/* mount point for filesystem */
51 	xfs_ino_t		ino,		/* inode to get data for */
52 	void __user		*buffer,	/* buffer to place output in */
53 	int			ubsize,		/* size of buffer */
54 	bulkstat_one_fmt_pf	formatter,	/* formatter, copy to user */
55 	int			*ubused,	/* bytes used by me */
56 	int			*stat)		/* BULKSTAT_RV_... */
57 {
58 	struct xfs_icdinode	*dic;		/* dinode core info pointer */
59 	struct xfs_inode	*ip;		/* incore inode pointer */
60 	struct inode		*inode;
61 	struct xfs_bstat	*buf;		/* return buffer */
62 	int			error = 0;	/* error value */
63 
64 	*stat = BULKSTAT_RV_NOTHING;
65 
66 	if (!buffer || xfs_internal_inum(mp, ino))
67 		return -EINVAL;
68 
69 	buf = kmem_zalloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
70 	if (!buf)
71 		return -ENOMEM;
72 
73 	error = xfs_iget(mp, NULL, ino,
74 			 (XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
75 			 XFS_ILOCK_SHARED, &ip);
76 	if (error)
77 		goto out_free;
78 
79 	ASSERT(ip != NULL);
80 	ASSERT(ip->i_imap.im_blkno != 0);
81 	inode = VFS_I(ip);
82 
83 	dic = &ip->i_d;
84 
85 	/* xfs_iget returns the following without needing
86 	 * further change.
87 	 */
88 	buf->bs_projid_lo = dic->di_projid_lo;
89 	buf->bs_projid_hi = dic->di_projid_hi;
90 	buf->bs_ino = ino;
91 	buf->bs_uid = dic->di_uid;
92 	buf->bs_gid = dic->di_gid;
93 	buf->bs_size = dic->di_size;
94 
95 	buf->bs_nlink = inode->i_nlink;
96 	buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
97 	buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
98 	buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
99 	buf->bs_mtime.tv_nsec = inode->i_mtime.tv_nsec;
100 	buf->bs_ctime.tv_sec = inode->i_ctime.tv_sec;
101 	buf->bs_ctime.tv_nsec = inode->i_ctime.tv_nsec;
102 	buf->bs_gen = inode->i_generation;
103 	buf->bs_mode = inode->i_mode;
104 
105 	buf->bs_xflags = xfs_ip2xflags(ip);
106 	buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
107 	buf->bs_extents = dic->di_nextents;
108 	memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
109 	buf->bs_dmevmask = dic->di_dmevmask;
110 	buf->bs_dmstate = dic->di_dmstate;
111 	buf->bs_aextents = dic->di_anextents;
112 	buf->bs_forkoff = XFS_IFORK_BOFF(ip);
113 
114 	if (dic->di_version == 3) {
115 		if (dic->di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
116 			buf->bs_cowextsize = dic->di_cowextsize <<
117 					mp->m_sb.sb_blocklog;
118 	}
119 
120 	switch (dic->di_format) {
121 	case XFS_DINODE_FMT_DEV:
122 		buf->bs_rdev = ip->i_df.if_u2.if_rdev;
123 		buf->bs_blksize = BLKDEV_IOSIZE;
124 		buf->bs_blocks = 0;
125 		break;
126 	case XFS_DINODE_FMT_LOCAL:
127 	case XFS_DINODE_FMT_UUID:
128 		buf->bs_rdev = 0;
129 		buf->bs_blksize = mp->m_sb.sb_blocksize;
130 		buf->bs_blocks = 0;
131 		break;
132 	case XFS_DINODE_FMT_EXTENTS:
133 	case XFS_DINODE_FMT_BTREE:
134 		buf->bs_rdev = 0;
135 		buf->bs_blksize = mp->m_sb.sb_blocksize;
136 		buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
137 		break;
138 	}
139 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
140 	IRELE(ip);
141 
142 	error = formatter(buffer, ubsize, ubused, buf);
143 	if (!error)
144 		*stat = BULKSTAT_RV_DIDONE;
145 
146  out_free:
147 	kmem_free(buf);
148 	return error;
149 }
150 
151 /* Return 0 on success or positive error */
152 STATIC int
153 xfs_bulkstat_one_fmt(
154 	void			__user *ubuffer,
155 	int			ubsize,
156 	int			*ubused,
157 	const xfs_bstat_t	*buffer)
158 {
159 	if (ubsize < sizeof(*buffer))
160 		return -ENOMEM;
161 	if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
162 		return -EFAULT;
163 	if (ubused)
164 		*ubused = sizeof(*buffer);
165 	return 0;
166 }
167 
168 int
169 xfs_bulkstat_one(
170 	xfs_mount_t	*mp,		/* mount point for filesystem */
171 	xfs_ino_t	ino,		/* inode number to get data for */
172 	void		__user *buffer,	/* buffer to place output in */
173 	int		ubsize,		/* size of buffer */
174 	int		*ubused,	/* bytes used by me */
175 	int		*stat)		/* BULKSTAT_RV_... */
176 {
177 	return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
178 				    xfs_bulkstat_one_fmt, ubused, stat);
179 }
180 
181 /*
182  * Loop over all clusters in a chunk for a given incore inode allocation btree
183  * record.  Do a readahead if there are any allocated inodes in that cluster.
184  */
185 STATIC void
186 xfs_bulkstat_ichunk_ra(
187 	struct xfs_mount		*mp,
188 	xfs_agnumber_t			agno,
189 	struct xfs_inobt_rec_incore	*irec)
190 {
191 	xfs_agblock_t			agbno;
192 	struct blk_plug			plug;
193 	int				blks_per_cluster;
194 	int				inodes_per_cluster;
195 	int				i;	/* inode chunk index */
196 
197 	agbno = XFS_AGINO_TO_AGBNO(mp, irec->ir_startino);
198 	blks_per_cluster = xfs_icluster_size_fsb(mp);
199 	inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
200 
201 	blk_start_plug(&plug);
202 	for (i = 0; i < XFS_INODES_PER_CHUNK;
203 	     i += inodes_per_cluster, agbno += blks_per_cluster) {
204 		if (xfs_inobt_maskn(i, inodes_per_cluster) & ~irec->ir_free) {
205 			xfs_btree_reada_bufs(mp, agno, agbno, blks_per_cluster,
206 					     &xfs_inode_buf_ops);
207 		}
208 	}
209 	blk_finish_plug(&plug);
210 }
211 
212 /*
213  * Lookup the inode chunk that the given inode lives in and then get the record
214  * if we found the chunk.  If the inode was not the last in the chunk and there
215  * are some left allocated, update the data for the pointed-to record as well as
216  * return the count of grabbed inodes.
217  */
218 STATIC int
219 xfs_bulkstat_grab_ichunk(
220 	struct xfs_btree_cur		*cur,	/* btree cursor */
221 	xfs_agino_t			agino,	/* starting inode of chunk */
222 	int				*icount,/* return # of inodes grabbed */
223 	struct xfs_inobt_rec_incore	*irec)	/* btree record */
224 {
225 	int				idx;	/* index into inode chunk */
226 	int				stat;
227 	int				error = 0;
228 
229 	/* Lookup the inode chunk that this inode lives in */
230 	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &stat);
231 	if (error)
232 		return error;
233 	if (!stat) {
234 		*icount = 0;
235 		return error;
236 	}
237 
238 	/* Get the record, should always work */
239 	error = xfs_inobt_get_rec(cur, irec, &stat);
240 	if (error)
241 		return error;
242 	XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, stat == 1);
243 
244 	/* Check if the record contains the inode in request */
245 	if (irec->ir_startino + XFS_INODES_PER_CHUNK <= agino) {
246 		*icount = 0;
247 		return 0;
248 	}
249 
250 	idx = agino - irec->ir_startino + 1;
251 	if (idx < XFS_INODES_PER_CHUNK &&
252 	    (xfs_inobt_maskn(idx, XFS_INODES_PER_CHUNK - idx) & ~irec->ir_free)) {
253 		int	i;
254 
255 		/* We got a right chunk with some left inodes allocated at it.
256 		 * Grab the chunk record.  Mark all the uninteresting inodes
257 		 * free -- because they're before our start point.
258 		 */
259 		for (i = 0; i < idx; i++) {
260 			if (XFS_INOBT_MASK(i) & ~irec->ir_free)
261 				irec->ir_freecount++;
262 		}
263 
264 		irec->ir_free |= xfs_inobt_maskn(0, idx);
265 		*icount = irec->ir_count - irec->ir_freecount;
266 	}
267 
268 	return 0;
269 }
270 
271 #define XFS_BULKSTAT_UBLEFT(ubleft)	((ubleft) >= statstruct_size)
272 
273 struct xfs_bulkstat_agichunk {
274 	char		__user **ac_ubuffer;/* pointer into user's buffer */
275 	int		ac_ubleft;	/* bytes left in user's buffer */
276 	int		ac_ubelem;	/* spaces used in user's buffer */
277 };
278 
279 /*
280  * Process inodes in chunk with a pointer to a formatter function
281  * that will iget the inode and fill in the appropriate structure.
282  */
283 static int
284 xfs_bulkstat_ag_ichunk(
285 	struct xfs_mount		*mp,
286 	xfs_agnumber_t			agno,
287 	struct xfs_inobt_rec_incore	*irbp,
288 	bulkstat_one_pf			formatter,
289 	size_t				statstruct_size,
290 	struct xfs_bulkstat_agichunk	*acp,
291 	xfs_agino_t			*last_agino)
292 {
293 	char				__user **ubufp = acp->ac_ubuffer;
294 	int				chunkidx;
295 	int				error = 0;
296 	xfs_agino_t			agino = irbp->ir_startino;
297 
298 	for (chunkidx = 0; chunkidx < XFS_INODES_PER_CHUNK;
299 	     chunkidx++, agino++) {
300 		int		fmterror;
301 		int		ubused;
302 
303 		/* inode won't fit in buffer, we are done */
304 		if (acp->ac_ubleft < statstruct_size)
305 			break;
306 
307 		/* Skip if this inode is free */
308 		if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free)
309 			continue;
310 
311 		/* Get the inode and fill in a single buffer */
312 		ubused = statstruct_size;
313 		error = formatter(mp, XFS_AGINO_TO_INO(mp, agno, agino),
314 				  *ubufp, acp->ac_ubleft, &ubused, &fmterror);
315 
316 		if (fmterror == BULKSTAT_RV_GIVEUP ||
317 		    (error && error != -ENOENT && error != -EINVAL)) {
318 			acp->ac_ubleft = 0;
319 			ASSERT(error);
320 			break;
321 		}
322 
323 		/* be careful not to leak error if at end of chunk */
324 		if (fmterror == BULKSTAT_RV_NOTHING || error) {
325 			error = 0;
326 			continue;
327 		}
328 
329 		*ubufp += ubused;
330 		acp->ac_ubleft -= ubused;
331 		acp->ac_ubelem++;
332 	}
333 
334 	/*
335 	 * Post-update *last_agino. At this point, agino will always point one
336 	 * inode past the last inode we processed successfully. Hence we
337 	 * substract that inode when setting the *last_agino cursor so that we
338 	 * return the correct cookie to userspace. On the next bulkstat call,
339 	 * the inode under the lastino cookie will be skipped as we have already
340 	 * processed it here.
341 	 */
342 	*last_agino = agino - 1;
343 
344 	return error;
345 }
346 
347 /*
348  * Return stat information in bulk (by-inode) for the filesystem.
349  */
350 int					/* error status */
351 xfs_bulkstat(
352 	xfs_mount_t		*mp,	/* mount point for filesystem */
353 	xfs_ino_t		*lastinop, /* last inode returned */
354 	int			*ubcountp, /* size of buffer/count returned */
355 	bulkstat_one_pf		formatter, /* func that'd fill a single buf */
356 	size_t			statstruct_size, /* sizeof struct filling */
357 	char			__user *ubuffer, /* buffer with inode stats */
358 	int			*done)	/* 1 if there are more stats to get */
359 {
360 	xfs_buf_t		*agbp;	/* agi header buffer */
361 	xfs_agino_t		agino;	/* inode # in allocation group */
362 	xfs_agnumber_t		agno;	/* allocation group number */
363 	xfs_btree_cur_t		*cur;	/* btree cursor for ialloc btree */
364 	xfs_inobt_rec_incore_t	*irbuf;	/* start of irec buffer */
365 	int			nirbuf;	/* size of irbuf */
366 	int			ubcount; /* size of user's buffer */
367 	struct xfs_bulkstat_agichunk ac;
368 	int			error = 0;
369 
370 	/*
371 	 * Get the last inode value, see if there's nothing to do.
372 	 */
373 	agno = XFS_INO_TO_AGNO(mp, *lastinop);
374 	agino = XFS_INO_TO_AGINO(mp, *lastinop);
375 	if (agno >= mp->m_sb.sb_agcount ||
376 	    *lastinop != XFS_AGINO_TO_INO(mp, agno, agino)) {
377 		*done = 1;
378 		*ubcountp = 0;
379 		return 0;
380 	}
381 
382 	ubcount = *ubcountp; /* statstruct's */
383 	ac.ac_ubuffer = &ubuffer;
384 	ac.ac_ubleft = ubcount * statstruct_size; /* bytes */;
385 	ac.ac_ubelem = 0;
386 
387 	*ubcountp = 0;
388 	*done = 0;
389 
390 	irbuf = kmem_zalloc_large(PAGE_SIZE * 4, KM_SLEEP);
391 	if (!irbuf)
392 		return -ENOMEM;
393 	nirbuf = (PAGE_SIZE * 4) / sizeof(*irbuf);
394 
395 	/*
396 	 * Loop over the allocation groups, starting from the last
397 	 * inode returned; 0 means start of the allocation group.
398 	 */
399 	while (agno < mp->m_sb.sb_agcount) {
400 		struct xfs_inobt_rec_incore	*irbp = irbuf;
401 		struct xfs_inobt_rec_incore	*irbufend = irbuf + nirbuf;
402 		bool				end_of_ag = false;
403 		int				icount = 0;
404 		int				stat;
405 
406 		error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
407 		if (error)
408 			break;
409 		/*
410 		 * Allocate and initialize a btree cursor for ialloc btree.
411 		 */
412 		cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
413 					    XFS_BTNUM_INO);
414 		if (agino > 0) {
415 			/*
416 			 * In the middle of an allocation group, we need to get
417 			 * the remainder of the chunk we're in.
418 			 */
419 			struct xfs_inobt_rec_incore	r;
420 
421 			error = xfs_bulkstat_grab_ichunk(cur, agino, &icount, &r);
422 			if (error)
423 				goto del_cursor;
424 			if (icount) {
425 				irbp->ir_startino = r.ir_startino;
426 				irbp->ir_holemask = r.ir_holemask;
427 				irbp->ir_count = r.ir_count;
428 				irbp->ir_freecount = r.ir_freecount;
429 				irbp->ir_free = r.ir_free;
430 				irbp++;
431 			}
432 			/* Increment to the next record */
433 			error = xfs_btree_increment(cur, 0, &stat);
434 		} else {
435 			/* Start of ag.  Lookup the first inode chunk */
436 			error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &stat);
437 		}
438 		if (error || stat == 0) {
439 			end_of_ag = true;
440 			goto del_cursor;
441 		}
442 
443 		/*
444 		 * Loop through inode btree records in this ag,
445 		 * until we run out of inodes or space in the buffer.
446 		 */
447 		while (irbp < irbufend && icount < ubcount) {
448 			struct xfs_inobt_rec_incore	r;
449 
450 			error = xfs_inobt_get_rec(cur, &r, &stat);
451 			if (error || stat == 0) {
452 				end_of_ag = true;
453 				goto del_cursor;
454 			}
455 
456 			/*
457 			 * If this chunk has any allocated inodes, save it.
458 			 * Also start read-ahead now for this chunk.
459 			 */
460 			if (r.ir_freecount < r.ir_count) {
461 				xfs_bulkstat_ichunk_ra(mp, agno, &r);
462 				irbp->ir_startino = r.ir_startino;
463 				irbp->ir_holemask = r.ir_holemask;
464 				irbp->ir_count = r.ir_count;
465 				irbp->ir_freecount = r.ir_freecount;
466 				irbp->ir_free = r.ir_free;
467 				irbp++;
468 				icount += r.ir_count - r.ir_freecount;
469 			}
470 			error = xfs_btree_increment(cur, 0, &stat);
471 			if (error || stat == 0) {
472 				end_of_ag = true;
473 				goto del_cursor;
474 			}
475 			cond_resched();
476 		}
477 
478 		/*
479 		 * Drop the btree buffers and the agi buffer as we can't hold any
480 		 * of the locks these represent when calling iget. If there is a
481 		 * pending error, then we are done.
482 		 */
483 del_cursor:
484 		xfs_btree_del_cursor(cur, error ?
485 					  XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
486 		xfs_buf_relse(agbp);
487 		if (error)
488 			break;
489 		/*
490 		 * Now format all the good inodes into the user's buffer. The
491 		 * call to xfs_bulkstat_ag_ichunk() sets up the agino pointer
492 		 * for the next loop iteration.
493 		 */
494 		irbufend = irbp;
495 		for (irbp = irbuf;
496 		     irbp < irbufend && ac.ac_ubleft >= statstruct_size;
497 		     irbp++) {
498 			error = xfs_bulkstat_ag_ichunk(mp, agno, irbp,
499 					formatter, statstruct_size, &ac,
500 					&agino);
501 			if (error)
502 				break;
503 
504 			cond_resched();
505 		}
506 
507 		/*
508 		 * If we've run out of space or had a formatting error, we
509 		 * are now done
510 		 */
511 		if (ac.ac_ubleft < statstruct_size || error)
512 			break;
513 
514 		if (end_of_ag) {
515 			agno++;
516 			agino = 0;
517 		}
518 	}
519 	/*
520 	 * Done, we're either out of filesystem or space to put the data.
521 	 */
522 	kmem_free(irbuf);
523 	*ubcountp = ac.ac_ubelem;
524 
525 	/*
526 	 * We found some inodes, so clear the error status and return them.
527 	 * The lastino pointer will point directly at the inode that triggered
528 	 * any error that occurred, so on the next call the error will be
529 	 * triggered again and propagated to userspace as there will be no
530 	 * formatted inodes in the buffer.
531 	 */
532 	if (ac.ac_ubelem)
533 		error = 0;
534 
535 	/*
536 	 * If we ran out of filesystem, lastino will point off the end of
537 	 * the filesystem so the next call will return immediately.
538 	 */
539 	*lastinop = XFS_AGINO_TO_INO(mp, agno, agino);
540 	if (agno >= mp->m_sb.sb_agcount)
541 		*done = 1;
542 
543 	return error;
544 }
545 
546 int
547 xfs_inumbers_fmt(
548 	void			__user *ubuffer, /* buffer to write to */
549 	const struct xfs_inogrp	*buffer,	/* buffer to read from */
550 	long			count,		/* # of elements to read */
551 	long			*written)	/* # of bytes written */
552 {
553 	if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
554 		return -EFAULT;
555 	*written = count * sizeof(*buffer);
556 	return 0;
557 }
558 
559 /*
560  * Return inode number table for the filesystem.
561  */
562 int					/* error status */
563 xfs_inumbers(
564 	struct xfs_mount	*mp,/* mount point for filesystem */
565 	xfs_ino_t		*lastino,/* last inode returned */
566 	int			*count,/* size of buffer/count returned */
567 	void			__user *ubuffer,/* buffer with inode descriptions */
568 	inumbers_fmt_pf		formatter)
569 {
570 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, *lastino);
571 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, *lastino);
572 	struct xfs_btree_cur	*cur = NULL;
573 	struct xfs_buf		*agbp = NULL;
574 	struct xfs_inogrp	*buffer;
575 	int			bcount;
576 	int			left = *count;
577 	int			bufidx = 0;
578 	int			error = 0;
579 
580 	*count = 0;
581 	if (agno >= mp->m_sb.sb_agcount ||
582 	    *lastino != XFS_AGINO_TO_INO(mp, agno, agino))
583 		return error;
584 
585 	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
586 	buffer = kmem_zalloc(bcount * sizeof(*buffer), KM_SLEEP);
587 	do {
588 		struct xfs_inobt_rec_incore	r;
589 		int				stat;
590 
591 		if (!agbp) {
592 			error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
593 			if (error)
594 				break;
595 
596 			cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
597 						    XFS_BTNUM_INO);
598 			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
599 						 &stat);
600 			if (error)
601 				break;
602 			if (!stat)
603 				goto next_ag;
604 		}
605 
606 		error = xfs_inobt_get_rec(cur, &r, &stat);
607 		if (error)
608 			break;
609 		if (!stat)
610 			goto next_ag;
611 
612 		agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
613 		buffer[bufidx].xi_startino =
614 			XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
615 		buffer[bufidx].xi_alloccount = r.ir_count - r.ir_freecount;
616 		buffer[bufidx].xi_allocmask = ~r.ir_free;
617 		if (++bufidx == bcount) {
618 			long	written;
619 
620 			error = formatter(ubuffer, buffer, bufidx, &written);
621 			if (error)
622 				break;
623 			ubuffer += written;
624 			*count += bufidx;
625 			bufidx = 0;
626 		}
627 		if (!--left)
628 			break;
629 
630 		error = xfs_btree_increment(cur, 0, &stat);
631 		if (error)
632 			break;
633 		if (stat)
634 			continue;
635 
636 next_ag:
637 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
638 		cur = NULL;
639 		xfs_buf_relse(agbp);
640 		agbp = NULL;
641 		agino = 0;
642 		agno++;
643 	} while (agno < mp->m_sb.sb_agcount);
644 
645 	if (!error) {
646 		if (bufidx) {
647 			long	written;
648 
649 			error = formatter(ubuffer, buffer, bufidx, &written);
650 			if (!error)
651 				*count += bufidx;
652 		}
653 		*lastino = XFS_AGINO_TO_INO(mp, agno, agino);
654 	}
655 
656 	kmem_free(buffer);
657 	if (cur)
658 		xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
659 					   XFS_BTREE_NOERROR));
660 	if (agbp)
661 		xfs_buf_relse(agbp);
662 
663 	return error;
664 }
665