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Linux 3.14
[~andy/linux] / fs / xfs / xfs_itable.c
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_inum.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_inode.h"
29 #include "xfs_btree.h"
30 #include "xfs_ialloc.h"
31 #include "xfs_ialloc_btree.h"
32 #include "xfs_itable.h"
33 #include "xfs_error.h"
34 #include "xfs_trace.h"
35 #include "xfs_icache.h"
36 #include "xfs_dinode.h"
37
38 STATIC int
39 xfs_internal_inum(
40         xfs_mount_t     *mp,
41         xfs_ino_t       ino)
42 {
43         return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
44                 (xfs_sb_version_hasquota(&mp->m_sb) &&
45                  xfs_is_quota_inode(&mp->m_sb, ino)));
46 }
47
48 /*
49  * Return stat information for one inode.
50  * Return 0 if ok, else errno.
51  */
52 int
53 xfs_bulkstat_one_int(
54         struct xfs_mount        *mp,            /* mount point for filesystem */
55         xfs_ino_t               ino,            /* inode to get data for */
56         void __user             *buffer,        /* buffer to place output in */
57         int                     ubsize,         /* size of buffer */
58         bulkstat_one_fmt_pf     formatter,      /* formatter, copy to user */
59         int                     *ubused,        /* bytes used by me */
60         int                     *stat)          /* BULKSTAT_RV_... */
61 {
62         struct xfs_icdinode     *dic;           /* dinode core info pointer */
63         struct xfs_inode        *ip;            /* incore inode pointer */
64         struct xfs_bstat        *buf;           /* return buffer */
65         int                     error = 0;      /* error value */
66
67         *stat = BULKSTAT_RV_NOTHING;
68
69         if (!buffer || xfs_internal_inum(mp, ino))
70                 return XFS_ERROR(EINVAL);
71
72         buf = kmem_alloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
73         if (!buf)
74                 return XFS_ERROR(ENOMEM);
75
76         error = xfs_iget(mp, NULL, ino,
77                          (XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
78                          XFS_ILOCK_SHARED, &ip);
79         if (error) {
80                 *stat = BULKSTAT_RV_NOTHING;
81                 goto out_free;
82         }
83
84         ASSERT(ip != NULL);
85         ASSERT(ip->i_imap.im_blkno != 0);
86
87         dic = &ip->i_d;
88
89         /* xfs_iget returns the following without needing
90          * further change.
91          */
92         buf->bs_nlink = dic->di_nlink;
93         buf->bs_projid_lo = dic->di_projid_lo;
94         buf->bs_projid_hi = dic->di_projid_hi;
95         buf->bs_ino = ino;
96         buf->bs_mode = dic->di_mode;
97         buf->bs_uid = dic->di_uid;
98         buf->bs_gid = dic->di_gid;
99         buf->bs_size = dic->di_size;
100         buf->bs_atime.tv_sec = dic->di_atime.t_sec;
101         buf->bs_atime.tv_nsec = dic->di_atime.t_nsec;
102         buf->bs_mtime.tv_sec = dic->di_mtime.t_sec;
103         buf->bs_mtime.tv_nsec = dic->di_mtime.t_nsec;
104         buf->bs_ctime.tv_sec = dic->di_ctime.t_sec;
105         buf->bs_ctime.tv_nsec = dic->di_ctime.t_nsec;
106         buf->bs_xflags = xfs_ip2xflags(ip);
107         buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
108         buf->bs_extents = dic->di_nextents;
109         buf->bs_gen = dic->di_gen;
110         memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
111         buf->bs_dmevmask = dic->di_dmevmask;
112         buf->bs_dmstate = dic->di_dmstate;
113         buf->bs_aextents = dic->di_anextents;
114         buf->bs_forkoff = XFS_IFORK_BOFF(ip);
115
116         switch (dic->di_format) {
117         case XFS_DINODE_FMT_DEV:
118                 buf->bs_rdev = ip->i_df.if_u2.if_rdev;
119                 buf->bs_blksize = BLKDEV_IOSIZE;
120                 buf->bs_blocks = 0;
121                 break;
122         case XFS_DINODE_FMT_LOCAL:
123         case XFS_DINODE_FMT_UUID:
124                 buf->bs_rdev = 0;
125                 buf->bs_blksize = mp->m_sb.sb_blocksize;
126                 buf->bs_blocks = 0;
127                 break;
128         case XFS_DINODE_FMT_EXTENTS:
129         case XFS_DINODE_FMT_BTREE:
130                 buf->bs_rdev = 0;
131                 buf->bs_blksize = mp->m_sb.sb_blocksize;
132                 buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
133                 break;
134         }
135         xfs_iunlock(ip, XFS_ILOCK_SHARED);
136         IRELE(ip);
137
138         error = formatter(buffer, ubsize, ubused, buf);
139
140         if (!error)
141                 *stat = BULKSTAT_RV_DIDONE;
142
143  out_free:
144         kmem_free(buf);
145         return error;
146 }
147
148 /* Return 0 on success or positive error */
149 STATIC int
150 xfs_bulkstat_one_fmt(
151         void                    __user *ubuffer,
152         int                     ubsize,
153         int                     *ubused,
154         const xfs_bstat_t       *buffer)
155 {
156         if (ubsize < sizeof(*buffer))
157                 return XFS_ERROR(ENOMEM);
158         if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
159                 return XFS_ERROR(EFAULT);
160         if (ubused)
161                 *ubused = sizeof(*buffer);
162         return 0;
163 }
164
165 int
166 xfs_bulkstat_one(
167         xfs_mount_t     *mp,            /* mount point for filesystem */
168         xfs_ino_t       ino,            /* inode number to get data for */
169         void            __user *buffer, /* buffer to place output in */
170         int             ubsize,         /* size of buffer */
171         int             *ubused,        /* bytes used by me */
172         int             *stat)          /* BULKSTAT_RV_... */
173 {
174         return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
175                                     xfs_bulkstat_one_fmt, ubused, stat);
176 }
177
178 #define XFS_BULKSTAT_UBLEFT(ubleft)     ((ubleft) >= statstruct_size)
179
180 /*
181  * Return stat information in bulk (by-inode) for the filesystem.
182  */
183 int                                     /* error status */
184 xfs_bulkstat(
185         xfs_mount_t             *mp,    /* mount point for filesystem */
186         xfs_ino_t               *lastinop, /* last inode returned */
187         int                     *ubcountp, /* size of buffer/count returned */
188         bulkstat_one_pf         formatter, /* func that'd fill a single buf */
189         size_t                  statstruct_size, /* sizeof struct filling */
190         char                    __user *ubuffer, /* buffer with inode stats */
191         int                     *done)  /* 1 if there are more stats to get */
192 {
193         xfs_agblock_t           agbno=0;/* allocation group block number */
194         xfs_buf_t               *agbp;  /* agi header buffer */
195         xfs_agi_t               *agi;   /* agi header data */
196         xfs_agino_t             agino;  /* inode # in allocation group */
197         xfs_agnumber_t          agno;   /* allocation group number */
198         int                     chunkidx; /* current index into inode chunk */
199         int                     clustidx; /* current index into inode cluster */
200         xfs_btree_cur_t         *cur;   /* btree cursor for ialloc btree */
201         int                     end_of_ag; /* set if we've seen the ag end */
202         int                     error;  /* error code */
203         int                     fmterror;/* bulkstat formatter result */
204         int                     i;      /* loop index */
205         int                     icount; /* count of inodes good in irbuf */
206         size_t                  irbsize; /* size of irec buffer in bytes */
207         xfs_ino_t               ino;    /* inode number (filesystem) */
208         xfs_inobt_rec_incore_t  *irbp;  /* current irec buffer pointer */
209         xfs_inobt_rec_incore_t  *irbuf; /* start of irec buffer */
210         xfs_inobt_rec_incore_t  *irbufend; /* end of good irec buffer entries */
211         xfs_ino_t               lastino; /* last inode number returned */
212         int                     blks_per_cluster; /* # of blocks per cluster */
213         int                     inodes_per_cluster;/* # of inodes per cluster */
214         int                     nirbuf; /* size of irbuf */
215         int                     rval;   /* return value error code */
216         int                     tmp;    /* result value from btree calls */
217         int                     ubcount; /* size of user's buffer */
218         int                     ubleft; /* bytes left in user's buffer */
219         char                    __user *ubufp;  /* pointer into user's buffer */
220         int                     ubelem; /* spaces used in user's buffer */
221         int                     ubused; /* bytes used by formatter */
222
223         /*
224          * Get the last inode value, see if there's nothing to do.
225          */
226         ino = (xfs_ino_t)*lastinop;
227         lastino = ino;
228         agno = XFS_INO_TO_AGNO(mp, ino);
229         agino = XFS_INO_TO_AGINO(mp, ino);
230         if (agno >= mp->m_sb.sb_agcount ||
231             ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
232                 *done = 1;
233                 *ubcountp = 0;
234                 return 0;
235         }
236         if (!ubcountp || *ubcountp <= 0) {
237                 return EINVAL;
238         }
239         ubcount = *ubcountp; /* statstruct's */
240         ubleft = ubcount * statstruct_size; /* bytes */
241         *ubcountp = ubelem = 0;
242         *done = 0;
243         fmterror = 0;
244         ubufp = ubuffer;
245         blks_per_cluster = xfs_icluster_size_fsb(mp);
246         inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
247         irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
248         if (!irbuf)
249                 return ENOMEM;
250
251         nirbuf = irbsize / sizeof(*irbuf);
252
253         /*
254          * Loop over the allocation groups, starting from the last
255          * inode returned; 0 means start of the allocation group.
256          */
257         rval = 0;
258         while (XFS_BULKSTAT_UBLEFT(ubleft) && agno < mp->m_sb.sb_agcount) {
259                 cond_resched();
260                 error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
261                 if (error) {
262                         /*
263                          * Skip this allocation group and go to the next one.
264                          */
265                         agno++;
266                         agino = 0;
267                         continue;
268                 }
269                 agi = XFS_BUF_TO_AGI(agbp);
270                 /*
271                  * Allocate and initialize a btree cursor for ialloc btree.
272                  */
273                 cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
274                 irbp = irbuf;
275                 irbufend = irbuf + nirbuf;
276                 end_of_ag = 0;
277                 /*
278                  * If we're returning in the middle of an allocation group,
279                  * we need to get the remainder of the chunk we're in.
280                  */
281                 if (agino > 0) {
282                         xfs_inobt_rec_incore_t r;
283
284                         /*
285                          * Lookup the inode chunk that this inode lives in.
286                          */
287                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE,
288                                                  &tmp);
289                         if (!error &&   /* no I/O error */
290                             tmp &&      /* lookup succeeded */
291                                         /* got the record, should always work */
292                             !(error = xfs_inobt_get_rec(cur, &r, &i)) &&
293                             i == 1 &&
294                                         /* this is the right chunk */
295                             agino < r.ir_startino + XFS_INODES_PER_CHUNK &&
296                                         /* lastino was not last in chunk */
297                             (chunkidx = agino - r.ir_startino + 1) <
298                                     XFS_INODES_PER_CHUNK &&
299                                         /* there are some left allocated */
300                             xfs_inobt_maskn(chunkidx,
301                                     XFS_INODES_PER_CHUNK - chunkidx) &
302                                     ~r.ir_free) {
303                                 /*
304                                  * Grab the chunk record.  Mark all the
305                                  * uninteresting inodes (because they're
306                                  * before our start point) free.
307                                  */
308                                 for (i = 0; i < chunkidx; i++) {
309                                         if (XFS_INOBT_MASK(i) & ~r.ir_free)
310                                                 r.ir_freecount++;
311                                 }
312                                 r.ir_free |= xfs_inobt_maskn(0, chunkidx);
313                                 irbp->ir_startino = r.ir_startino;
314                                 irbp->ir_freecount = r.ir_freecount;
315                                 irbp->ir_free = r.ir_free;
316                                 irbp++;
317                                 agino = r.ir_startino + XFS_INODES_PER_CHUNK;
318                                 icount = XFS_INODES_PER_CHUNK - r.ir_freecount;
319                         } else {
320                                 /*
321                                  * If any of those tests failed, bump the
322                                  * inode number (just in case).
323                                  */
324                                 agino++;
325                                 icount = 0;
326                         }
327                         /*
328                          * In any case, increment to the next record.
329                          */
330                         if (!error)
331                                 error = xfs_btree_increment(cur, 0, &tmp);
332                 } else {
333                         /*
334                          * Start of ag.  Lookup the first inode chunk.
335                          */
336                         error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);
337                         icount = 0;
338                 }
339                 /*
340                  * Loop through inode btree records in this ag,
341                  * until we run out of inodes or space in the buffer.
342                  */
343                 while (irbp < irbufend && icount < ubcount) {
344                         xfs_inobt_rec_incore_t r;
345
346                         /*
347                          * Loop as long as we're unable to read the
348                          * inode btree.
349                          */
350                         while (error) {
351                                 agino += XFS_INODES_PER_CHUNK;
352                                 if (XFS_AGINO_TO_AGBNO(mp, agino) >=
353                                                 be32_to_cpu(agi->agi_length))
354                                         break;
355                                 error = xfs_inobt_lookup(cur, agino,
356                                                          XFS_LOOKUP_GE, &tmp);
357                                 cond_resched();
358                         }
359                         /*
360                          * If ran off the end of the ag either with an error,
361                          * or the normal way, set end and stop collecting.
362                          */
363                         if (error) {
364                                 end_of_ag = 1;
365                                 break;
366                         }
367
368                         error = xfs_inobt_get_rec(cur, &r, &i);
369                         if (error || i == 0) {
370                                 end_of_ag = 1;
371                                 break;
372                         }
373
374                         /*
375                          * If this chunk has any allocated inodes, save it.
376                          * Also start read-ahead now for this chunk.
377                          */
378                         if (r.ir_freecount < XFS_INODES_PER_CHUNK) {
379                                 struct blk_plug plug;
380                                 /*
381                                  * Loop over all clusters in the next chunk.
382                                  * Do a readahead if there are any allocated
383                                  * inodes in that cluster.
384                                  */
385                                 blk_start_plug(&plug);
386                                 agbno = XFS_AGINO_TO_AGBNO(mp, r.ir_startino);
387                                 for (chunkidx = 0;
388                                      chunkidx < XFS_INODES_PER_CHUNK;
389                                      chunkidx += inodes_per_cluster,
390                                      agbno += blks_per_cluster) {
391                                         if (xfs_inobt_maskn(chunkidx,
392                                             inodes_per_cluster) & ~r.ir_free)
393                                                 xfs_btree_reada_bufs(mp, agno,
394                                                         agbno, blks_per_cluster,
395                                                         &xfs_inode_buf_ops);
396                                 }
397                                 blk_finish_plug(&plug);
398                                 irbp->ir_startino = r.ir_startino;
399                                 irbp->ir_freecount = r.ir_freecount;
400                                 irbp->ir_free = r.ir_free;
401                                 irbp++;
402                                 icount += XFS_INODES_PER_CHUNK - r.ir_freecount;
403                         }
404                         /*
405                          * Set agino to after this chunk and bump the cursor.
406                          */
407                         agino = r.ir_startino + XFS_INODES_PER_CHUNK;
408                         error = xfs_btree_increment(cur, 0, &tmp);
409                         cond_resched();
410                 }
411                 /*
412                  * Drop the btree buffers and the agi buffer.
413                  * We can't hold any of the locks these represent
414                  * when calling iget.
415                  */
416                 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
417                 xfs_buf_relse(agbp);
418                 /*
419                  * Now format all the good inodes into the user's buffer.
420                  */
421                 irbufend = irbp;
422                 for (irbp = irbuf;
423                      irbp < irbufend && XFS_BULKSTAT_UBLEFT(ubleft); irbp++) {
424                         /*
425                          * Now process this chunk of inodes.
426                          */
427                         for (agino = irbp->ir_startino, chunkidx = clustidx = 0;
428                              XFS_BULKSTAT_UBLEFT(ubleft) &&
429                                 irbp->ir_freecount < XFS_INODES_PER_CHUNK;
430                              chunkidx++, clustidx++, agino++) {
431                                 ASSERT(chunkidx < XFS_INODES_PER_CHUNK);
432
433                                 ino = XFS_AGINO_TO_INO(mp, agno, agino);
434                                 /*
435                                  * Skip if this inode is free.
436                                  */
437                                 if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) {
438                                         lastino = ino;
439                                         continue;
440                                 }
441                                 /*
442                                  * Count used inodes as free so we can tell
443                                  * when the chunk is used up.
444                                  */
445                                 irbp->ir_freecount++;
446
447                                 /*
448                                  * Get the inode and fill in a single buffer.
449                                  */
450                                 ubused = statstruct_size;
451                                 error = formatter(mp, ino, ubufp, ubleft,
452                                                   &ubused, &fmterror);
453                                 if (fmterror == BULKSTAT_RV_NOTHING) {
454                                         if (error && error != ENOENT &&
455                                                 error != EINVAL) {
456                                                 ubleft = 0;
457                                                 rval = error;
458                                                 break;
459                                         }
460                                         lastino = ino;
461                                         continue;
462                                 }
463                                 if (fmterror == BULKSTAT_RV_GIVEUP) {
464                                         ubleft = 0;
465                                         ASSERT(error);
466                                         rval = error;
467                                         break;
468                                 }
469                                 if (ubufp)
470                                         ubufp += ubused;
471                                 ubleft -= ubused;
472                                 ubelem++;
473                                 lastino = ino;
474                         }
475
476                         cond_resched();
477                 }
478                 /*
479                  * Set up for the next loop iteration.
480                  */
481                 if (XFS_BULKSTAT_UBLEFT(ubleft)) {
482                         if (end_of_ag) {
483                                 agno++;
484                                 agino = 0;
485                         } else
486                                 agino = XFS_INO_TO_AGINO(mp, lastino);
487                 } else
488                         break;
489         }
490         /*
491          * Done, we're either out of filesystem or space to put the data.
492          */
493         kmem_free(irbuf);
494         *ubcountp = ubelem;
495         /*
496          * Found some inodes, return them now and return the error next time.
497          */
498         if (ubelem)
499                 rval = 0;
500         if (agno >= mp->m_sb.sb_agcount) {
501                 /*
502                  * If we ran out of filesystem, mark lastino as off
503                  * the end of the filesystem, so the next call
504                  * will return immediately.
505                  */
506                 *lastinop = (xfs_ino_t)XFS_AGINO_TO_INO(mp, agno, 0);
507                 *done = 1;
508         } else
509                 *lastinop = (xfs_ino_t)lastino;
510
511         return rval;
512 }
513
514 /*
515  * Return stat information in bulk (by-inode) for the filesystem.
516  * Special case for non-sequential one inode bulkstat.
517  */
518 int                                     /* error status */
519 xfs_bulkstat_single(
520         xfs_mount_t             *mp,    /* mount point for filesystem */
521         xfs_ino_t               *lastinop, /* inode to return */
522         char                    __user *buffer, /* buffer with inode stats */
523         int                     *done)  /* 1 if there are more stats to get */
524 {
525         int                     count;  /* count value for bulkstat call */
526         int                     error;  /* return value */
527         xfs_ino_t               ino;    /* filesystem inode number */
528         int                     res;    /* result from bs1 */
529
530         /*
531          * note that requesting valid inode numbers which are not allocated
532          * to inodes will most likely cause xfs_imap_to_bp to generate warning
533          * messages about bad magic numbers. This is ok. The fact that
534          * the inode isn't actually an inode is handled by the
535          * error check below. Done this way to make the usual case faster
536          * at the expense of the error case.
537          */
538
539         ino = *lastinop;
540         error = xfs_bulkstat_one(mp, ino, buffer, sizeof(xfs_bstat_t),
541                                  NULL, &res);
542         if (error) {
543                 /*
544                  * Special case way failed, do it the "long" way
545                  * to see if that works.
546                  */
547                 (*lastinop)--;
548                 count = 1;
549                 if (xfs_bulkstat(mp, lastinop, &count, xfs_bulkstat_one,
550                                 sizeof(xfs_bstat_t), buffer, done))
551                         return error;
552                 if (count == 0 || (xfs_ino_t)*lastinop != ino)
553                         return error == EFSCORRUPTED ?
554                                 XFS_ERROR(EINVAL) : error;
555                 else
556                         return 0;
557         }
558         *done = 0;
559         return 0;
560 }
561
562 int
563 xfs_inumbers_fmt(
564         void                    __user *ubuffer, /* buffer to write to */
565         const xfs_inogrp_t      *buffer,        /* buffer to read from */
566         long                    count,          /* # of elements to read */
567         long                    *written)       /* # of bytes written */
568 {
569         if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
570                 return -EFAULT;
571         *written = count * sizeof(*buffer);
572         return 0;
573 }
574
575 /*
576  * Return inode number table for the filesystem.
577  */
578 int                                     /* error status */
579 xfs_inumbers(
580         xfs_mount_t     *mp,            /* mount point for filesystem */
581         xfs_ino_t       *lastino,       /* last inode returned */
582         int             *count,         /* size of buffer/count returned */
583         void            __user *ubuffer,/* buffer with inode descriptions */
584         inumbers_fmt_pf formatter)
585 {
586         xfs_buf_t       *agbp;
587         xfs_agino_t     agino;
588         xfs_agnumber_t  agno;
589         int             bcount;
590         xfs_inogrp_t    *buffer;
591         int             bufidx;
592         xfs_btree_cur_t *cur;
593         int             error;
594         xfs_inobt_rec_incore_t r;
595         int             i;
596         xfs_ino_t       ino;
597         int             left;
598         int             tmp;
599
600         ino = (xfs_ino_t)*lastino;
601         agno = XFS_INO_TO_AGNO(mp, ino);
602         agino = XFS_INO_TO_AGINO(mp, ino);
603         left = *count;
604         *count = 0;
605         bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
606         buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
607         error = bufidx = 0;
608         cur = NULL;
609         agbp = NULL;
610         while (left > 0 && agno < mp->m_sb.sb_agcount) {
611                 if (agbp == NULL) {
612                         error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
613                         if (error) {
614                                 /*
615                                  * If we can't read the AGI of this ag,
616                                  * then just skip to the next one.
617                                  */
618                                 ASSERT(cur == NULL);
619                                 agbp = NULL;
620                                 agno++;
621                                 agino = 0;
622                                 continue;
623                         }
624                         cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
625                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
626                                                  &tmp);
627                         if (error) {
628                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
629                                 cur = NULL;
630                                 xfs_buf_relse(agbp);
631                                 agbp = NULL;
632                                 /*
633                                  * Move up the last inode in the current
634                                  * chunk.  The lookup_ge will always get
635                                  * us the first inode in the next chunk.
636                                  */
637                                 agino += XFS_INODES_PER_CHUNK - 1;
638                                 continue;
639                         }
640                 }
641                 error = xfs_inobt_get_rec(cur, &r, &i);
642                 if (error || i == 0) {
643                         xfs_buf_relse(agbp);
644                         agbp = NULL;
645                         xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
646                         cur = NULL;
647                         agno++;
648                         agino = 0;
649                         continue;
650                 }
651                 agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
652                 buffer[bufidx].xi_startino =
653                         XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
654                 buffer[bufidx].xi_alloccount =
655                         XFS_INODES_PER_CHUNK - r.ir_freecount;
656                 buffer[bufidx].xi_allocmask = ~r.ir_free;
657                 bufidx++;
658                 left--;
659                 if (bufidx == bcount) {
660                         long written;
661                         if (formatter(ubuffer, buffer, bufidx, &written)) {
662                                 error = XFS_ERROR(EFAULT);
663                                 break;
664                         }
665                         ubuffer += written;
666                         *count += bufidx;
667                         bufidx = 0;
668                 }
669                 if (left) {
670                         error = xfs_btree_increment(cur, 0, &tmp);
671                         if (error) {
672                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
673                                 cur = NULL;
674                                 xfs_buf_relse(agbp);
675                                 agbp = NULL;
676                                 /*
677                                  * The agino value has already been bumped.
678                                  * Just try to skip up to it.
679                                  */
680                                 agino += XFS_INODES_PER_CHUNK;
681                                 continue;
682                         }
683                 }
684         }
685         if (!error) {
686                 if (bufidx) {
687                         long written;
688                         if (formatter(ubuffer, buffer, bufidx, &written))
689                                 error = XFS_ERROR(EFAULT);
690                         else
691                                 *count += bufidx;
692                 }
693                 *lastino = XFS_AGINO_TO_INO(mp, agno, agino);
694         }
695         kmem_free(buffer);
696         if (cur)
697                 xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
698                                            XFS_BTREE_NOERROR));
699         if (agbp)
700                 xfs_buf_relse(agbp);
701         return error;
702 }