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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                     nbcluster; /* # of blocks in a cluster */
213         int                     nicluster; /* # of inodes in a cluster */
214         int                     nimask; /* mask for inode clusters */
215         int                     nirbuf; /* size of irbuf */
216         int                     rval;   /* return value error code */
217         int                     tmp;    /* result value from btree calls */
218         int                     ubcount; /* size of user's buffer */
219         int                     ubleft; /* bytes left in user's buffer */
220         char                    __user *ubufp;  /* pointer into user's buffer */
221         int                     ubelem; /* spaces used in user's buffer */
222         int                     ubused; /* bytes used by formatter */
223
224         /*
225          * Get the last inode value, see if there's nothing to do.
226          */
227         ino = (xfs_ino_t)*lastinop;
228         lastino = ino;
229         agno = XFS_INO_TO_AGNO(mp, ino);
230         agino = XFS_INO_TO_AGINO(mp, ino);
231         if (agno >= mp->m_sb.sb_agcount ||
232             ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
233                 *done = 1;
234                 *ubcountp = 0;
235                 return 0;
236         }
237         if (!ubcountp || *ubcountp <= 0) {
238                 return EINVAL;
239         }
240         ubcount = *ubcountp; /* statstruct's */
241         ubleft = ubcount * statstruct_size; /* bytes */
242         *ubcountp = ubelem = 0;
243         *done = 0;
244         fmterror = 0;
245         ubufp = ubuffer;
246         nicluster = mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp) ?
247                 mp->m_sb.sb_inopblock :
248                 (XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog);
249         nimask = ~(nicluster - 1);
250         nbcluster = nicluster >> mp->m_sb.sb_inopblog;
251         irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
252         if (!irbuf)
253                 return ENOMEM;
254
255         nirbuf = irbsize / sizeof(*irbuf);
256
257         /*
258          * Loop over the allocation groups, starting from the last
259          * inode returned; 0 means start of the allocation group.
260          */
261         rval = 0;
262         while (XFS_BULKSTAT_UBLEFT(ubleft) && agno < mp->m_sb.sb_agcount) {
263                 cond_resched();
264                 error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
265                 if (error) {
266                         /*
267                          * Skip this allocation group and go to the next one.
268                          */
269                         agno++;
270                         agino = 0;
271                         continue;
272                 }
273                 agi = XFS_BUF_TO_AGI(agbp);
274                 /*
275                  * Allocate and initialize a btree cursor for ialloc btree.
276                  */
277                 cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
278                 irbp = irbuf;
279                 irbufend = irbuf + nirbuf;
280                 end_of_ag = 0;
281                 /*
282                  * If we're returning in the middle of an allocation group,
283                  * we need to get the remainder of the chunk we're in.
284                  */
285                 if (agino > 0) {
286                         xfs_inobt_rec_incore_t r;
287
288                         /*
289                          * Lookup the inode chunk that this inode lives in.
290                          */
291                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE,
292                                                  &tmp);
293                         if (!error &&   /* no I/O error */
294                             tmp &&      /* lookup succeeded */
295                                         /* got the record, should always work */
296                             !(error = xfs_inobt_get_rec(cur, &r, &i)) &&
297                             i == 1 &&
298                                         /* this is the right chunk */
299                             agino < r.ir_startino + XFS_INODES_PER_CHUNK &&
300                                         /* lastino was not last in chunk */
301                             (chunkidx = agino - r.ir_startino + 1) <
302                                     XFS_INODES_PER_CHUNK &&
303                                         /* there are some left allocated */
304                             xfs_inobt_maskn(chunkidx,
305                                     XFS_INODES_PER_CHUNK - chunkidx) &
306                                     ~r.ir_free) {
307                                 /*
308                                  * Grab the chunk record.  Mark all the
309                                  * uninteresting inodes (because they're
310                                  * before our start point) free.
311                                  */
312                                 for (i = 0; i < chunkidx; i++) {
313                                         if (XFS_INOBT_MASK(i) & ~r.ir_free)
314                                                 r.ir_freecount++;
315                                 }
316                                 r.ir_free |= xfs_inobt_maskn(0, chunkidx);
317                                 irbp->ir_startino = r.ir_startino;
318                                 irbp->ir_freecount = r.ir_freecount;
319                                 irbp->ir_free = r.ir_free;
320                                 irbp++;
321                                 agino = r.ir_startino + XFS_INODES_PER_CHUNK;
322                                 icount = XFS_INODES_PER_CHUNK - r.ir_freecount;
323                         } else {
324                                 /*
325                                  * If any of those tests failed, bump the
326                                  * inode number (just in case).
327                                  */
328                                 agino++;
329                                 icount = 0;
330                         }
331                         /*
332                          * In any case, increment to the next record.
333                          */
334                         if (!error)
335                                 error = xfs_btree_increment(cur, 0, &tmp);
336                 } else {
337                         /*
338                          * Start of ag.  Lookup the first inode chunk.
339                          */
340                         error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);
341                         icount = 0;
342                 }
343                 /*
344                  * Loop through inode btree records in this ag,
345                  * until we run out of inodes or space in the buffer.
346                  */
347                 while (irbp < irbufend && icount < ubcount) {
348                         xfs_inobt_rec_incore_t r;
349
350                         /*
351                          * Loop as long as we're unable to read the
352                          * inode btree.
353                          */
354                         while (error) {
355                                 agino += XFS_INODES_PER_CHUNK;
356                                 if (XFS_AGINO_TO_AGBNO(mp, agino) >=
357                                                 be32_to_cpu(agi->agi_length))
358                                         break;
359                                 error = xfs_inobt_lookup(cur, agino,
360                                                          XFS_LOOKUP_GE, &tmp);
361                                 cond_resched();
362                         }
363                         /*
364                          * If ran off the end of the ag either with an error,
365                          * or the normal way, set end and stop collecting.
366                          */
367                         if (error) {
368                                 end_of_ag = 1;
369                                 break;
370                         }
371
372                         error = xfs_inobt_get_rec(cur, &r, &i);
373                         if (error || i == 0) {
374                                 end_of_ag = 1;
375                                 break;
376                         }
377
378                         /*
379                          * If this chunk has any allocated inodes, save it.
380                          * Also start read-ahead now for this chunk.
381                          */
382                         if (r.ir_freecount < XFS_INODES_PER_CHUNK) {
383                                 struct blk_plug plug;
384                                 /*
385                                  * Loop over all clusters in the next chunk.
386                                  * Do a readahead if there are any allocated
387                                  * inodes in that cluster.
388                                  */
389                                 blk_start_plug(&plug);
390                                 agbno = XFS_AGINO_TO_AGBNO(mp, r.ir_startino);
391                                 for (chunkidx = 0;
392                                      chunkidx < XFS_INODES_PER_CHUNK;
393                                      chunkidx += nicluster,
394                                      agbno += nbcluster) {
395                                         if (xfs_inobt_maskn(chunkidx, nicluster)
396                                                         & ~r.ir_free)
397                                                 xfs_btree_reada_bufs(mp, agno,
398                                                         agbno, nbcluster,
399                                                         &xfs_inode_buf_ops);
400                                 }
401                                 blk_finish_plug(&plug);
402                                 irbp->ir_startino = r.ir_startino;
403                                 irbp->ir_freecount = r.ir_freecount;
404                                 irbp->ir_free = r.ir_free;
405                                 irbp++;
406                                 icount += XFS_INODES_PER_CHUNK - r.ir_freecount;
407                         }
408                         /*
409                          * Set agino to after this chunk and bump the cursor.
410                          */
411                         agino = r.ir_startino + XFS_INODES_PER_CHUNK;
412                         error = xfs_btree_increment(cur, 0, &tmp);
413                         cond_resched();
414                 }
415                 /*
416                  * Drop the btree buffers and the agi buffer.
417                  * We can't hold any of the locks these represent
418                  * when calling iget.
419                  */
420                 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
421                 xfs_buf_relse(agbp);
422                 /*
423                  * Now format all the good inodes into the user's buffer.
424                  */
425                 irbufend = irbp;
426                 for (irbp = irbuf;
427                      irbp < irbufend && XFS_BULKSTAT_UBLEFT(ubleft); irbp++) {
428                         /*
429                          * Now process this chunk of inodes.
430                          */
431                         for (agino = irbp->ir_startino, chunkidx = clustidx = 0;
432                              XFS_BULKSTAT_UBLEFT(ubleft) &&
433                                 irbp->ir_freecount < XFS_INODES_PER_CHUNK;
434                              chunkidx++, clustidx++, agino++) {
435                                 ASSERT(chunkidx < XFS_INODES_PER_CHUNK);
436
437                                 ino = XFS_AGINO_TO_INO(mp, agno, agino);
438                                 /*
439                                  * Skip if this inode is free.
440                                  */
441                                 if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) {
442                                         lastino = ino;
443                                         continue;
444                                 }
445                                 /*
446                                  * Count used inodes as free so we can tell
447                                  * when the chunk is used up.
448                                  */
449                                 irbp->ir_freecount++;
450
451                                 /*
452                                  * Get the inode and fill in a single buffer.
453                                  */
454                                 ubused = statstruct_size;
455                                 error = formatter(mp, ino, ubufp, ubleft,
456                                                   &ubused, &fmterror);
457                                 if (fmterror == BULKSTAT_RV_NOTHING) {
458                                         if (error && error != ENOENT &&
459                                                 error != EINVAL) {
460                                                 ubleft = 0;
461                                                 rval = error;
462                                                 break;
463                                         }
464                                         lastino = ino;
465                                         continue;
466                                 }
467                                 if (fmterror == BULKSTAT_RV_GIVEUP) {
468                                         ubleft = 0;
469                                         ASSERT(error);
470                                         rval = error;
471                                         break;
472                                 }
473                                 if (ubufp)
474                                         ubufp += ubused;
475                                 ubleft -= ubused;
476                                 ubelem++;
477                                 lastino = ino;
478                         }
479
480                         cond_resched();
481                 }
482                 /*
483                  * Set up for the next loop iteration.
484                  */
485                 if (XFS_BULKSTAT_UBLEFT(ubleft)) {
486                         if (end_of_ag) {
487                                 agno++;
488                                 agino = 0;
489                         } else
490                                 agino = XFS_INO_TO_AGINO(mp, lastino);
491                 } else
492                         break;
493         }
494         /*
495          * Done, we're either out of filesystem or space to put the data.
496          */
497         kmem_free(irbuf);
498         *ubcountp = ubelem;
499         /*
500          * Found some inodes, return them now and return the error next time.
501          */
502         if (ubelem)
503                 rval = 0;
504         if (agno >= mp->m_sb.sb_agcount) {
505                 /*
506                  * If we ran out of filesystem, mark lastino as off
507                  * the end of the filesystem, so the next call
508                  * will return immediately.
509                  */
510                 *lastinop = (xfs_ino_t)XFS_AGINO_TO_INO(mp, agno, 0);
511                 *done = 1;
512         } else
513                 *lastinop = (xfs_ino_t)lastino;
514
515         return rval;
516 }
517
518 /*
519  * Return stat information in bulk (by-inode) for the filesystem.
520  * Special case for non-sequential one inode bulkstat.
521  */
522 int                                     /* error status */
523 xfs_bulkstat_single(
524         xfs_mount_t             *mp,    /* mount point for filesystem */
525         xfs_ino_t               *lastinop, /* inode to return */
526         char                    __user *buffer, /* buffer with inode stats */
527         int                     *done)  /* 1 if there are more stats to get */
528 {
529         int                     count;  /* count value for bulkstat call */
530         int                     error;  /* return value */
531         xfs_ino_t               ino;    /* filesystem inode number */
532         int                     res;    /* result from bs1 */
533
534         /*
535          * note that requesting valid inode numbers which are not allocated
536          * to inodes will most likely cause xfs_imap_to_bp to generate warning
537          * messages about bad magic numbers. This is ok. The fact that
538          * the inode isn't actually an inode is handled by the
539          * error check below. Done this way to make the usual case faster
540          * at the expense of the error case.
541          */
542
543         ino = *lastinop;
544         error = xfs_bulkstat_one(mp, ino, buffer, sizeof(xfs_bstat_t),
545                                  NULL, &res);
546         if (error) {
547                 /*
548                  * Special case way failed, do it the "long" way
549                  * to see if that works.
550                  */
551                 (*lastinop)--;
552                 count = 1;
553                 if (xfs_bulkstat(mp, lastinop, &count, xfs_bulkstat_one,
554                                 sizeof(xfs_bstat_t), buffer, done))
555                         return error;
556                 if (count == 0 || (xfs_ino_t)*lastinop != ino)
557                         return error == EFSCORRUPTED ?
558                                 XFS_ERROR(EINVAL) : error;
559                 else
560                         return 0;
561         }
562         *done = 0;
563         return 0;
564 }
565
566 int
567 xfs_inumbers_fmt(
568         void                    __user *ubuffer, /* buffer to write to */
569         const xfs_inogrp_t      *buffer,        /* buffer to read from */
570         long                    count,          /* # of elements to read */
571         long                    *written)       /* # of bytes written */
572 {
573         if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
574                 return -EFAULT;
575         *written = count * sizeof(*buffer);
576         return 0;
577 }
578
579 /*
580  * Return inode number table for the filesystem.
581  */
582 int                                     /* error status */
583 xfs_inumbers(
584         xfs_mount_t     *mp,            /* mount point for filesystem */
585         xfs_ino_t       *lastino,       /* last inode returned */
586         int             *count,         /* size of buffer/count returned */
587         void            __user *ubuffer,/* buffer with inode descriptions */
588         inumbers_fmt_pf formatter)
589 {
590         xfs_buf_t       *agbp;
591         xfs_agino_t     agino;
592         xfs_agnumber_t  agno;
593         int             bcount;
594         xfs_inogrp_t    *buffer;
595         int             bufidx;
596         xfs_btree_cur_t *cur;
597         int             error;
598         xfs_inobt_rec_incore_t r;
599         int             i;
600         xfs_ino_t       ino;
601         int             left;
602         int             tmp;
603
604         ino = (xfs_ino_t)*lastino;
605         agno = XFS_INO_TO_AGNO(mp, ino);
606         agino = XFS_INO_TO_AGINO(mp, ino);
607         left = *count;
608         *count = 0;
609         bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
610         buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
611         error = bufidx = 0;
612         cur = NULL;
613         agbp = NULL;
614         while (left > 0 && agno < mp->m_sb.sb_agcount) {
615                 if (agbp == NULL) {
616                         error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
617                         if (error) {
618                                 /*
619                                  * If we can't read the AGI of this ag,
620                                  * then just skip to the next one.
621                                  */
622                                 ASSERT(cur == NULL);
623                                 agbp = NULL;
624                                 agno++;
625                                 agino = 0;
626                                 continue;
627                         }
628                         cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
629                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
630                                                  &tmp);
631                         if (error) {
632                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
633                                 cur = NULL;
634                                 xfs_buf_relse(agbp);
635                                 agbp = NULL;
636                                 /*
637                                  * Move up the last inode in the current
638                                  * chunk.  The lookup_ge will always get
639                                  * us the first inode in the next chunk.
640                                  */
641                                 agino += XFS_INODES_PER_CHUNK - 1;
642                                 continue;
643                         }
644                 }
645                 error = xfs_inobt_get_rec(cur, &r, &i);
646                 if (error || i == 0) {
647                         xfs_buf_relse(agbp);
648                         agbp = NULL;
649                         xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
650                         cur = NULL;
651                         agno++;
652                         agino = 0;
653                         continue;
654                 }
655                 agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
656                 buffer[bufidx].xi_startino =
657                         XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
658                 buffer[bufidx].xi_alloccount =
659                         XFS_INODES_PER_CHUNK - r.ir_freecount;
660                 buffer[bufidx].xi_allocmask = ~r.ir_free;
661                 bufidx++;
662                 left--;
663                 if (bufidx == bcount) {
664                         long written;
665                         if (formatter(ubuffer, buffer, bufidx, &written)) {
666                                 error = XFS_ERROR(EFAULT);
667                                 break;
668                         }
669                         ubuffer += written;
670                         *count += bufidx;
671                         bufidx = 0;
672                 }
673                 if (left) {
674                         error = xfs_btree_increment(cur, 0, &tmp);
675                         if (error) {
676                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
677                                 cur = NULL;
678                                 xfs_buf_relse(agbp);
679                                 agbp = NULL;
680                                 /*
681                                  * The agino value has already been bumped.
682                                  * Just try to skip up to it.
683                                  */
684                                 agino += XFS_INODES_PER_CHUNK;
685                                 continue;
686                         }
687                 }
688         }
689         if (!error) {
690                 if (bufidx) {
691                         long written;
692                         if (formatter(ubuffer, buffer, bufidx, &written))
693                                 error = XFS_ERROR(EFAULT);
694                         else
695                                 *count += bufidx;
696                 }
697                 *lastino = XFS_AGINO_TO_INO(mp, agno, agino);
698         }
699         kmem_free(buffer);
700         if (cur)
701                 xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
702                                            XFS_BTREE_NOERROR));
703         if (agbp)
704                 xfs_buf_relse(agbp);
705         return error;
706 }