xref: /linux/fs/xfs/xfs_itable.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 xfs_bstat	*buf;		/* return buffer */
61 	int			error = 0;	/* error value */
62 
63 	*stat = BULKSTAT_RV_NOTHING;
64 
65 	if (!buffer || xfs_internal_inum(mp, ino))
66 		return -EINVAL;
67 
68 	buf = kmem_alloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
69 	if (!buf)
70 		return -ENOMEM;
71 
72 	error = xfs_iget(mp, NULL, ino,
73 			 (XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
74 			 XFS_ILOCK_SHARED, &ip);
75 	if (error)
76 		goto out_free;
77 
78 	ASSERT(ip != NULL);
79 	ASSERT(ip->i_imap.im_blkno != 0);
80 
81 	dic = &ip->i_d;
82 
83 	/* xfs_iget returns the following without needing
84 	 * further change.
85 	 */
86 	buf->bs_nlink = dic->di_nlink;
87 	buf->bs_projid_lo = dic->di_projid_lo;
88 	buf->bs_projid_hi = dic->di_projid_hi;
89 	buf->bs_ino = ino;
90 	buf->bs_mode = dic->di_mode;
91 	buf->bs_uid = dic->di_uid;
92 	buf->bs_gid = dic->di_gid;
93 	buf->bs_size = dic->di_size;
94 	buf->bs_atime.tv_sec = dic->di_atime.t_sec;
95 	buf->bs_atime.tv_nsec = dic->di_atime.t_nsec;
96 	buf->bs_mtime.tv_sec = dic->di_mtime.t_sec;
97 	buf->bs_mtime.tv_nsec = dic->di_mtime.t_nsec;
98 	buf->bs_ctime.tv_sec = dic->di_ctime.t_sec;
99 	buf->bs_ctime.tv_nsec = dic->di_ctime.t_nsec;
100 	buf->bs_xflags = xfs_ip2xflags(ip);
101 	buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
102 	buf->bs_extents = dic->di_nextents;
103 	buf->bs_gen = dic->di_gen;
104 	memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
105 	buf->bs_dmevmask = dic->di_dmevmask;
106 	buf->bs_dmstate = dic->di_dmstate;
107 	buf->bs_aextents = dic->di_anextents;
108 	buf->bs_forkoff = XFS_IFORK_BOFF(ip);
109 
110 	switch (dic->di_format) {
111 	case XFS_DINODE_FMT_DEV:
112 		buf->bs_rdev = ip->i_df.if_u2.if_rdev;
113 		buf->bs_blksize = BLKDEV_IOSIZE;
114 		buf->bs_blocks = 0;
115 		break;
116 	case XFS_DINODE_FMT_LOCAL:
117 	case XFS_DINODE_FMT_UUID:
118 		buf->bs_rdev = 0;
119 		buf->bs_blksize = mp->m_sb.sb_blocksize;
120 		buf->bs_blocks = 0;
121 		break;
122 	case XFS_DINODE_FMT_EXTENTS:
123 	case XFS_DINODE_FMT_BTREE:
124 		buf->bs_rdev = 0;
125 		buf->bs_blksize = mp->m_sb.sb_blocksize;
126 		buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
127 		break;
128 	}
129 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
130 	IRELE(ip);
131 
132 	error = formatter(buffer, ubsize, ubused, buf);
133 	if (!error)
134 		*stat = BULKSTAT_RV_DIDONE;
135 
136  out_free:
137 	kmem_free(buf);
138 	return error;
139 }
140 
141 /* Return 0 on success or positive error */
142 STATIC int
143 xfs_bulkstat_one_fmt(
144 	void			__user *ubuffer,
145 	int			ubsize,
146 	int			*ubused,
147 	const xfs_bstat_t	*buffer)
148 {
149 	if (ubsize < sizeof(*buffer))
150 		return -ENOMEM;
151 	if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
152 		return -EFAULT;
153 	if (ubused)
154 		*ubused = sizeof(*buffer);
155 	return 0;
156 }
157 
158 int
159 xfs_bulkstat_one(
160 	xfs_mount_t	*mp,		/* mount point for filesystem */
161 	xfs_ino_t	ino,		/* inode number to get data for */
162 	void		__user *buffer,	/* buffer to place output in */
163 	int		ubsize,		/* size of buffer */
164 	int		*ubused,	/* bytes used by me */
165 	int		*stat)		/* BULKSTAT_RV_... */
166 {
167 	return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
168 				    xfs_bulkstat_one_fmt, ubused, stat);
169 }
170 
171 /*
172  * Loop over all clusters in a chunk for a given incore inode allocation btree
173  * record.  Do a readahead if there are any allocated inodes in that cluster.
174  */
175 STATIC void
176 xfs_bulkstat_ichunk_ra(
177 	struct xfs_mount		*mp,
178 	xfs_agnumber_t			agno,
179 	struct xfs_inobt_rec_incore	*irec)
180 {
181 	xfs_agblock_t			agbno;
182 	struct blk_plug			plug;
183 	int				blks_per_cluster;
184 	int				inodes_per_cluster;
185 	int				i;	/* inode chunk index */
186 
187 	agbno = XFS_AGINO_TO_AGBNO(mp, irec->ir_startino);
188 	blks_per_cluster = xfs_icluster_size_fsb(mp);
189 	inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
190 
191 	blk_start_plug(&plug);
192 	for (i = 0; i < XFS_INODES_PER_CHUNK;
193 	     i += inodes_per_cluster, agbno += blks_per_cluster) {
194 		if (xfs_inobt_maskn(i, inodes_per_cluster) & ~irec->ir_free) {
195 			xfs_btree_reada_bufs(mp, agno, agbno, blks_per_cluster,
196 					     &xfs_inode_buf_ops);
197 		}
198 	}
199 	blk_finish_plug(&plug);
200 }
201 
202 /*
203  * Lookup the inode chunk that the given inode lives in and then get the record
204  * if we found the chunk.  If the inode was not the last in the chunk and there
205  * are some left allocated, update the data for the pointed-to record as well as
206  * return the count of grabbed inodes.
207  */
208 STATIC int
209 xfs_bulkstat_grab_ichunk(
210 	struct xfs_btree_cur		*cur,	/* btree cursor */
211 	xfs_agino_t			agino,	/* starting inode of chunk */
212 	int				*icount,/* return # of inodes grabbed */
213 	struct xfs_inobt_rec_incore	*irec)	/* btree record */
214 {
215 	int				idx;	/* index into inode chunk */
216 	int				stat;
217 	int				error = 0;
218 
219 	/* Lookup the inode chunk that this inode lives in */
220 	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &stat);
221 	if (error)
222 		return error;
223 	if (!stat) {
224 		*icount = 0;
225 		return error;
226 	}
227 
228 	/* Get the record, should always work */
229 	error = xfs_inobt_get_rec(cur, irec, &stat);
230 	if (error)
231 		return error;
232 	XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, stat == 1);
233 
234 	/* Check if the record contains the inode in request */
235 	if (irec->ir_startino + XFS_INODES_PER_CHUNK <= agino) {
236 		*icount = 0;
237 		return 0;
238 	}
239 
240 	idx = agino - irec->ir_startino + 1;
241 	if (idx < XFS_INODES_PER_CHUNK &&
242 	    (xfs_inobt_maskn(idx, XFS_INODES_PER_CHUNK - idx) & ~irec->ir_free)) {
243 		int	i;
244 
245 		/* We got a right chunk with some left inodes allocated at it.
246 		 * Grab the chunk record.  Mark all the uninteresting inodes
247 		 * free -- because they're before our start point.
248 		 */
249 		for (i = 0; i < idx; i++) {
250 			if (XFS_INOBT_MASK(i) & ~irec->ir_free)
251 				irec->ir_freecount++;
252 		}
253 
254 		irec->ir_free |= xfs_inobt_maskn(0, idx);
255 		*icount = irec->ir_count - irec->ir_freecount;
256 	}
257 
258 	return 0;
259 }
260 
261 #define XFS_BULKSTAT_UBLEFT(ubleft)	((ubleft) >= statstruct_size)
262 
263 struct xfs_bulkstat_agichunk {
264 	char		__user **ac_ubuffer;/* pointer into user's buffer */
265 	int		ac_ubleft;	/* bytes left in user's buffer */
266 	int		ac_ubelem;	/* spaces used in user's buffer */
267 };
268 
269 /*
270  * Process inodes in chunk with a pointer to a formatter function
271  * that will iget the inode and fill in the appropriate structure.
272  */
273 static int
274 xfs_bulkstat_ag_ichunk(
275 	struct xfs_mount		*mp,
276 	xfs_agnumber_t			agno,
277 	struct xfs_inobt_rec_incore	*irbp,
278 	bulkstat_one_pf			formatter,
279 	size_t				statstruct_size,
280 	struct xfs_bulkstat_agichunk	*acp,
281 	xfs_agino_t			*last_agino)
282 {
283 	char				__user **ubufp = acp->ac_ubuffer;
284 	int				chunkidx;
285 	int				error = 0;
286 	xfs_agino_t			agino = irbp->ir_startino;
287 
288 	for (chunkidx = 0; chunkidx < XFS_INODES_PER_CHUNK;
289 	     chunkidx++, agino++) {
290 		int		fmterror;
291 		int		ubused;
292 
293 		/* inode won't fit in buffer, we are done */
294 		if (acp->ac_ubleft < statstruct_size)
295 			break;
296 
297 		/* Skip if this inode is free */
298 		if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free)
299 			continue;
300 
301 		/* Get the inode and fill in a single buffer */
302 		ubused = statstruct_size;
303 		error = formatter(mp, XFS_AGINO_TO_INO(mp, agno, agino),
304 				  *ubufp, acp->ac_ubleft, &ubused, &fmterror);
305 
306 		if (fmterror == BULKSTAT_RV_GIVEUP ||
307 		    (error && error != -ENOENT && error != -EINVAL)) {
308 			acp->ac_ubleft = 0;
309 			ASSERT(error);
310 			break;
311 		}
312 
313 		/* be careful not to leak error if at end of chunk */
314 		if (fmterror == BULKSTAT_RV_NOTHING || error) {
315 			error = 0;
316 			continue;
317 		}
318 
319 		*ubufp += ubused;
320 		acp->ac_ubleft -= ubused;
321 		acp->ac_ubelem++;
322 	}
323 
324 	/*
325 	 * Post-update *last_agino. At this point, agino will always point one
326 	 * inode past the last inode we processed successfully. Hence we
327 	 * substract that inode when setting the *last_agino cursor so that we
328 	 * return the correct cookie to userspace. On the next bulkstat call,
329 	 * the inode under the lastino cookie will be skipped as we have already
330 	 * processed it here.
331 	 */
332 	*last_agino = agino - 1;
333 
334 	return error;
335 }
336 
337 /*
338  * Return stat information in bulk (by-inode) for the filesystem.
339  */
340 int					/* error status */
341 xfs_bulkstat(
342 	xfs_mount_t		*mp,	/* mount point for filesystem */
343 	xfs_ino_t		*lastinop, /* last inode returned */
344 	int			*ubcountp, /* size of buffer/count returned */
345 	bulkstat_one_pf		formatter, /* func that'd fill a single buf */
346 	size_t			statstruct_size, /* sizeof struct filling */
347 	char			__user *ubuffer, /* buffer with inode stats */
348 	int			*done)	/* 1 if there are more stats to get */
349 {
350 	xfs_buf_t		*agbp;	/* agi header buffer */
351 	xfs_agino_t		agino;	/* inode # in allocation group */
352 	xfs_agnumber_t		agno;	/* allocation group number */
353 	xfs_btree_cur_t		*cur;	/* btree cursor for ialloc btree */
354 	size_t			irbsize; /* size of irec buffer in bytes */
355 	xfs_inobt_rec_incore_t	*irbuf;	/* start of irec buffer */
356 	int			nirbuf;	/* size of irbuf */
357 	int			ubcount; /* size of user's buffer */
358 	struct xfs_bulkstat_agichunk ac;
359 	int			error = 0;
360 
361 	/*
362 	 * Get the last inode value, see if there's nothing to do.
363 	 */
364 	agno = XFS_INO_TO_AGNO(mp, *lastinop);
365 	agino = XFS_INO_TO_AGINO(mp, *lastinop);
366 	if (agno >= mp->m_sb.sb_agcount ||
367 	    *lastinop != XFS_AGINO_TO_INO(mp, agno, agino)) {
368 		*done = 1;
369 		*ubcountp = 0;
370 		return 0;
371 	}
372 
373 	ubcount = *ubcountp; /* statstruct's */
374 	ac.ac_ubuffer = &ubuffer;
375 	ac.ac_ubleft = ubcount * statstruct_size; /* bytes */;
376 	ac.ac_ubelem = 0;
377 
378 	*ubcountp = 0;
379 	*done = 0;
380 
381 	irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
382 	if (!irbuf)
383 		return -ENOMEM;
384 
385 	nirbuf = irbsize / sizeof(*irbuf);
386 
387 	/*
388 	 * Loop over the allocation groups, starting from the last
389 	 * inode returned; 0 means start of the allocation group.
390 	 */
391 	while (agno < mp->m_sb.sb_agcount) {
392 		struct xfs_inobt_rec_incore	*irbp = irbuf;
393 		struct xfs_inobt_rec_incore	*irbufend = irbuf + nirbuf;
394 		bool				end_of_ag = false;
395 		int				icount = 0;
396 		int				stat;
397 
398 		error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
399 		if (error)
400 			break;
401 		/*
402 		 * Allocate and initialize a btree cursor for ialloc btree.
403 		 */
404 		cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
405 					    XFS_BTNUM_INO);
406 		if (agino > 0) {
407 			/*
408 			 * In the middle of an allocation group, we need to get
409 			 * the remainder of the chunk we're in.
410 			 */
411 			struct xfs_inobt_rec_incore	r;
412 
413 			error = xfs_bulkstat_grab_ichunk(cur, agino, &icount, &r);
414 			if (error)
415 				goto del_cursor;
416 			if (icount) {
417 				irbp->ir_startino = r.ir_startino;
418 				irbp->ir_holemask = r.ir_holemask;
419 				irbp->ir_count = r.ir_count;
420 				irbp->ir_freecount = r.ir_freecount;
421 				irbp->ir_free = r.ir_free;
422 				irbp++;
423 			}
424 			/* Increment to the next record */
425 			error = xfs_btree_increment(cur, 0, &stat);
426 		} else {
427 			/* Start of ag.  Lookup the first inode chunk */
428 			error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &stat);
429 		}
430 		if (error || stat == 0) {
431 			end_of_ag = true;
432 			goto del_cursor;
433 		}
434 
435 		/*
436 		 * Loop through inode btree records in this ag,
437 		 * until we run out of inodes or space in the buffer.
438 		 */
439 		while (irbp < irbufend && icount < ubcount) {
440 			struct xfs_inobt_rec_incore	r;
441 
442 			error = xfs_inobt_get_rec(cur, &r, &stat);
443 			if (error || stat == 0) {
444 				end_of_ag = true;
445 				goto del_cursor;
446 			}
447 
448 			/*
449 			 * If this chunk has any allocated inodes, save it.
450 			 * Also start read-ahead now for this chunk.
451 			 */
452 			if (r.ir_freecount < r.ir_count) {
453 				xfs_bulkstat_ichunk_ra(mp, agno, &r);
454 				irbp->ir_startino = r.ir_startino;
455 				irbp->ir_holemask = r.ir_holemask;
456 				irbp->ir_count = r.ir_count;
457 				irbp->ir_freecount = r.ir_freecount;
458 				irbp->ir_free = r.ir_free;
459 				irbp++;
460 				icount += r.ir_count - r.ir_freecount;
461 			}
462 			error = xfs_btree_increment(cur, 0, &stat);
463 			if (error || stat == 0) {
464 				end_of_ag = true;
465 				goto del_cursor;
466 			}
467 			cond_resched();
468 		}
469 
470 		/*
471 		 * Drop the btree buffers and the agi buffer as we can't hold any
472 		 * of the locks these represent when calling iget. If there is a
473 		 * pending error, then we are done.
474 		 */
475 del_cursor:
476 		xfs_btree_del_cursor(cur, error ?
477 					  XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
478 		xfs_buf_relse(agbp);
479 		if (error)
480 			break;
481 		/*
482 		 * Now format all the good inodes into the user's buffer. The
483 		 * call to xfs_bulkstat_ag_ichunk() sets up the agino pointer
484 		 * for the next loop iteration.
485 		 */
486 		irbufend = irbp;
487 		for (irbp = irbuf;
488 		     irbp < irbufend && ac.ac_ubleft >= statstruct_size;
489 		     irbp++) {
490 			error = xfs_bulkstat_ag_ichunk(mp, agno, irbp,
491 					formatter, statstruct_size, &ac,
492 					&agino);
493 			if (error)
494 				break;
495 
496 			cond_resched();
497 		}
498 
499 		/*
500 		 * If we've run out of space or had a formatting error, we
501 		 * are now done
502 		 */
503 		if (ac.ac_ubleft < statstruct_size || error)
504 			break;
505 
506 		if (end_of_ag) {
507 			agno++;
508 			agino = 0;
509 		}
510 	}
511 	/*
512 	 * Done, we're either out of filesystem or space to put the data.
513 	 */
514 	kmem_free(irbuf);
515 	*ubcountp = ac.ac_ubelem;
516 
517 	/*
518 	 * We found some inodes, so clear the error status and return them.
519 	 * The lastino pointer will point directly at the inode that triggered
520 	 * any error that occurred, so on the next call the error will be
521 	 * triggered again and propagated to userspace as there will be no
522 	 * formatted inodes in the buffer.
523 	 */
524 	if (ac.ac_ubelem)
525 		error = 0;
526 
527 	/*
528 	 * If we ran out of filesystem, lastino will point off the end of
529 	 * the filesystem so the next call will return immediately.
530 	 */
531 	*lastinop = XFS_AGINO_TO_INO(mp, agno, agino);
532 	if (agno >= mp->m_sb.sb_agcount)
533 		*done = 1;
534 
535 	return error;
536 }
537 
538 int
539 xfs_inumbers_fmt(
540 	void			__user *ubuffer, /* buffer to write to */
541 	const struct xfs_inogrp	*buffer,	/* buffer to read from */
542 	long			count,		/* # of elements to read */
543 	long			*written)	/* # of bytes written */
544 {
545 	if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
546 		return -EFAULT;
547 	*written = count * sizeof(*buffer);
548 	return 0;
549 }
550 
551 /*
552  * Return inode number table for the filesystem.
553  */
554 int					/* error status */
555 xfs_inumbers(
556 	struct xfs_mount	*mp,/* mount point for filesystem */
557 	xfs_ino_t		*lastino,/* last inode returned */
558 	int			*count,/* size of buffer/count returned */
559 	void			__user *ubuffer,/* buffer with inode descriptions */
560 	inumbers_fmt_pf		formatter)
561 {
562 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, *lastino);
563 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, *lastino);
564 	struct xfs_btree_cur	*cur = NULL;
565 	struct xfs_buf		*agbp = NULL;
566 	struct xfs_inogrp	*buffer;
567 	int			bcount;
568 	int			left = *count;
569 	int			bufidx = 0;
570 	int			error = 0;
571 
572 	*count = 0;
573 	if (agno >= mp->m_sb.sb_agcount ||
574 	    *lastino != XFS_AGINO_TO_INO(mp, agno, agino))
575 		return error;
576 
577 	bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
578 	buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
579 	do {
580 		struct xfs_inobt_rec_incore	r;
581 		int				stat;
582 
583 		if (!agbp) {
584 			error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
585 			if (error)
586 				break;
587 
588 			cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno,
589 						    XFS_BTNUM_INO);
590 			error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
591 						 &stat);
592 			if (error)
593 				break;
594 			if (!stat)
595 				goto next_ag;
596 		}
597 
598 		error = xfs_inobt_get_rec(cur, &r, &stat);
599 		if (error)
600 			break;
601 		if (!stat)
602 			goto next_ag;
603 
604 		agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
605 		buffer[bufidx].xi_startino =
606 			XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
607 		buffer[bufidx].xi_alloccount = r.ir_count - r.ir_freecount;
608 		buffer[bufidx].xi_allocmask = ~r.ir_free;
609 		if (++bufidx == bcount) {
610 			long	written;
611 
612 			error = formatter(ubuffer, buffer, bufidx, &written);
613 			if (error)
614 				break;
615 			ubuffer += written;
616 			*count += bufidx;
617 			bufidx = 0;
618 		}
619 		if (!--left)
620 			break;
621 
622 		error = xfs_btree_increment(cur, 0, &stat);
623 		if (error)
624 			break;
625 		if (stat)
626 			continue;
627 
628 next_ag:
629 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
630 		cur = NULL;
631 		xfs_buf_relse(agbp);
632 		agbp = NULL;
633 		agino = 0;
634 		agno++;
635 	} while (agno < mp->m_sb.sb_agcount);
636 
637 	if (!error) {
638 		if (bufidx) {
639 			long	written;
640 
641 			error = formatter(ubuffer, buffer, bufidx, &written);
642 			if (!error)
643 				*count += bufidx;
644 		}
645 		*lastino = XFS_AGINO_TO_INO(mp, agno, agino);
646 	}
647 
648 	kmem_free(buffer);
649 	if (cur)
650 		xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
651 					   XFS_BTREE_NOERROR));
652 	if (agbp)
653 		xfs_buf_relse(agbp);
654 
655 	return error;
656 }
657