Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland...
[sfrench/cifs-2.6.git] / 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_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_alloc_btree.h"
30 #include "xfs_ialloc_btree.h"
31 #include "xfs_dinode.h"
32 #include "xfs_inode.h"
33 #include "xfs_ialloc.h"
34 #include "xfs_itable.h"
35 #include "xfs_error.h"
36 #include "xfs_btree.h"
37 #include "xfs_trace.h"
38
39 STATIC int
40 xfs_internal_inum(
41         xfs_mount_t     *mp,
42         xfs_ino_t       ino)
43 {
44         return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
45                 (xfs_sb_version_hasquota(&mp->m_sb) &&
46                  (ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino)));
47 }
48
49 /*
50  * Return stat information for one inode.
51  * Return 0 if ok, else errno.
52  */
53 int
54 xfs_bulkstat_one_int(
55         struct xfs_mount        *mp,            /* mount point for filesystem */
56         xfs_ino_t               ino,            /* inode to get data for */
57         void __user             *buffer,        /* buffer to place output in */
58         int                     ubsize,         /* size of buffer */
59         bulkstat_one_fmt_pf     formatter,      /* formatter, copy to user */
60         int                     *ubused,        /* bytes used by me */
61         int                     *stat)          /* BULKSTAT_RV_... */
62 {
63         struct xfs_icdinode     *dic;           /* dinode core info pointer */
64         struct xfs_inode        *ip;            /* incore inode pointer */
65         struct inode            *inode;
66         struct xfs_bstat        *buf;           /* return buffer */
67         int                     error = 0;      /* error value */
68
69         *stat = BULKSTAT_RV_NOTHING;
70
71         if (!buffer || xfs_internal_inum(mp, ino))
72                 return XFS_ERROR(EINVAL);
73
74         buf = kmem_alloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
75         if (!buf)
76                 return XFS_ERROR(ENOMEM);
77
78         error = xfs_iget(mp, NULL, ino,
79                          XFS_IGET_UNTRUSTED, XFS_ILOCK_SHARED, &ip);
80         if (error) {
81                 *stat = BULKSTAT_RV_NOTHING;
82                 goto out_free;
83         }
84
85         ASSERT(ip != NULL);
86         ASSERT(ip->i_imap.im_blkno != 0);
87
88         dic = &ip->i_d;
89         inode = VFS_I(ip);
90
91         /* xfs_iget returns the following without needing
92          * further change.
93          */
94         buf->bs_nlink = dic->di_nlink;
95         buf->bs_projid = dic->di_projid;
96         buf->bs_ino = ino;
97         buf->bs_mode = dic->di_mode;
98         buf->bs_uid = dic->di_uid;
99         buf->bs_gid = dic->di_gid;
100         buf->bs_size = dic->di_size;
101
102         /*
103          * We need to read the timestamps from the Linux inode because
104          * the VFS keeps writing directly into the inode structure instead
105          * of telling us about the updates.
106          */
107         buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
108         buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
109         buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
110         buf->bs_mtime.tv_nsec = inode->i_mtime.tv_nsec;
111         buf->bs_ctime.tv_sec = inode->i_ctime.tv_sec;
112         buf->bs_ctime.tv_nsec = inode->i_ctime.tv_nsec;
113
114         buf->bs_xflags = xfs_ip2xflags(ip);
115         buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
116         buf->bs_extents = dic->di_nextents;
117         buf->bs_gen = dic->di_gen;
118         memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
119         buf->bs_dmevmask = dic->di_dmevmask;
120         buf->bs_dmstate = dic->di_dmstate;
121         buf->bs_aextents = dic->di_anextents;
122         buf->bs_forkoff = XFS_IFORK_BOFF(ip);
123
124         switch (dic->di_format) {
125         case XFS_DINODE_FMT_DEV:
126                 buf->bs_rdev = ip->i_df.if_u2.if_rdev;
127                 buf->bs_blksize = BLKDEV_IOSIZE;
128                 buf->bs_blocks = 0;
129                 break;
130         case XFS_DINODE_FMT_LOCAL:
131         case XFS_DINODE_FMT_UUID:
132                 buf->bs_rdev = 0;
133                 buf->bs_blksize = mp->m_sb.sb_blocksize;
134                 buf->bs_blocks = 0;
135                 break;
136         case XFS_DINODE_FMT_EXTENTS:
137         case XFS_DINODE_FMT_BTREE:
138                 buf->bs_rdev = 0;
139                 buf->bs_blksize = mp->m_sb.sb_blocksize;
140                 buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
141                 break;
142         }
143         xfs_iunlock(ip, XFS_ILOCK_SHARED);
144         IRELE(ip);
145
146         error = formatter(buffer, ubsize, ubused, buf);
147
148         if (!error)
149                 *stat = BULKSTAT_RV_DIDONE;
150
151  out_free:
152         kmem_free(buf);
153         return error;
154 }
155
156 /* Return 0 on success or positive error */
157 STATIC int
158 xfs_bulkstat_one_fmt(
159         void                    __user *ubuffer,
160         int                     ubsize,
161         int                     *ubused,
162         const xfs_bstat_t       *buffer)
163 {
164         if (ubsize < sizeof(*buffer))
165                 return XFS_ERROR(ENOMEM);
166         if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
167                 return XFS_ERROR(EFAULT);
168         if (ubused)
169                 *ubused = sizeof(*buffer);
170         return 0;
171 }
172
173 int
174 xfs_bulkstat_one(
175         xfs_mount_t     *mp,            /* mount point for filesystem */
176         xfs_ino_t       ino,            /* inode number to get data for */
177         void            __user *buffer, /* buffer to place output in */
178         int             ubsize,         /* size of buffer */
179         int             *ubused,        /* bytes used by me */
180         int             *stat)          /* BULKSTAT_RV_... */
181 {
182         return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
183                                     xfs_bulkstat_one_fmt, ubused, stat);
184 }
185
186 #define XFS_BULKSTAT_UBLEFT(ubleft)     ((ubleft) >= statstruct_size)
187
188 /*
189  * Return stat information in bulk (by-inode) for the filesystem.
190  */
191 int                                     /* error status */
192 xfs_bulkstat(
193         xfs_mount_t             *mp,    /* mount point for filesystem */
194         xfs_ino_t               *lastinop, /* last inode returned */
195         int                     *ubcountp, /* size of buffer/count returned */
196         bulkstat_one_pf         formatter, /* func that'd fill a single buf */
197         size_t                  statstruct_size, /* sizeof struct filling */
198         char                    __user *ubuffer, /* buffer with inode stats */
199         int                     *done)  /* 1 if there are more stats to get */
200 {
201         xfs_agblock_t           agbno=0;/* allocation group block number */
202         xfs_buf_t               *agbp;  /* agi header buffer */
203         xfs_agi_t               *agi;   /* agi header data */
204         xfs_agino_t             agino;  /* inode # in allocation group */
205         xfs_agnumber_t          agno;   /* allocation group number */
206         xfs_daddr_t             bno;    /* inode cluster start daddr */
207         int                     chunkidx; /* current index into inode chunk */
208         int                     clustidx; /* current index into inode cluster */
209         xfs_btree_cur_t         *cur;   /* btree cursor for ialloc btree */
210         int                     end_of_ag; /* set if we've seen the ag end */
211         int                     error;  /* error code */
212         int                     fmterror;/* bulkstat formatter result */
213         int                     i;      /* loop index */
214         int                     icount; /* count of inodes good in irbuf */
215         size_t                  irbsize; /* size of irec buffer in bytes */
216         xfs_ino_t               ino;    /* inode number (filesystem) */
217         xfs_inobt_rec_incore_t  *irbp;  /* current irec buffer pointer */
218         xfs_inobt_rec_incore_t  *irbuf; /* start of irec buffer */
219         xfs_inobt_rec_incore_t  *irbufend; /* end of good irec buffer entries */
220         xfs_ino_t               lastino; /* last inode number returned */
221         int                     nbcluster; /* # of blocks in a cluster */
222         int                     nicluster; /* # of inodes in a cluster */
223         int                     nimask; /* mask for inode clusters */
224         int                     nirbuf; /* size of irbuf */
225         int                     rval;   /* return value error code */
226         int                     tmp;    /* result value from btree calls */
227         int                     ubcount; /* size of user's buffer */
228         int                     ubleft; /* bytes left in user's buffer */
229         char                    __user *ubufp;  /* pointer into user's buffer */
230         int                     ubelem; /* spaces used in user's buffer */
231         int                     ubused; /* bytes used by formatter */
232         xfs_buf_t               *bp;    /* ptr to on-disk inode cluster buf */
233
234         /*
235          * Get the last inode value, see if there's nothing to do.
236          */
237         ino = (xfs_ino_t)*lastinop;
238         lastino = ino;
239         agno = XFS_INO_TO_AGNO(mp, ino);
240         agino = XFS_INO_TO_AGINO(mp, ino);
241         if (agno >= mp->m_sb.sb_agcount ||
242             ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
243                 *done = 1;
244                 *ubcountp = 0;
245                 return 0;
246         }
247         if (!ubcountp || *ubcountp <= 0) {
248                 return EINVAL;
249         }
250         ubcount = *ubcountp; /* statstruct's */
251         ubleft = ubcount * statstruct_size; /* bytes */
252         *ubcountp = ubelem = 0;
253         *done = 0;
254         fmterror = 0;
255         ubufp = ubuffer;
256         nicluster = mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp) ?
257                 mp->m_sb.sb_inopblock :
258                 (XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog);
259         nimask = ~(nicluster - 1);
260         nbcluster = nicluster >> mp->m_sb.sb_inopblog;
261         irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
262         if (!irbuf)
263                 return ENOMEM;
264
265         nirbuf = irbsize / sizeof(*irbuf);
266
267         /*
268          * Loop over the allocation groups, starting from the last
269          * inode returned; 0 means start of the allocation group.
270          */
271         rval = 0;
272         while (XFS_BULKSTAT_UBLEFT(ubleft) && agno < mp->m_sb.sb_agcount) {
273                 cond_resched();
274                 bp = NULL;
275                 error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
276                 if (error) {
277                         /*
278                          * Skip this allocation group and go to the next one.
279                          */
280                         agno++;
281                         agino = 0;
282                         continue;
283                 }
284                 agi = XFS_BUF_TO_AGI(agbp);
285                 /*
286                  * Allocate and initialize a btree cursor for ialloc btree.
287                  */
288                 cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
289                 irbp = irbuf;
290                 irbufend = irbuf + nirbuf;
291                 end_of_ag = 0;
292                 /*
293                  * If we're returning in the middle of an allocation group,
294                  * we need to get the remainder of the chunk we're in.
295                  */
296                 if (agino > 0) {
297                         xfs_inobt_rec_incore_t r;
298
299                         /*
300                          * Lookup the inode chunk that this inode lives in.
301                          */
302                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE,
303                                                  &tmp);
304                         if (!error &&   /* no I/O error */
305                             tmp &&      /* lookup succeeded */
306                                         /* got the record, should always work */
307                             !(error = xfs_inobt_get_rec(cur, &r, &i)) &&
308                             i == 1 &&
309                                         /* this is the right chunk */
310                             agino < r.ir_startino + XFS_INODES_PER_CHUNK &&
311                                         /* lastino was not last in chunk */
312                             (chunkidx = agino - r.ir_startino + 1) <
313                                     XFS_INODES_PER_CHUNK &&
314                                         /* there are some left allocated */
315                             xfs_inobt_maskn(chunkidx,
316                                     XFS_INODES_PER_CHUNK - chunkidx) &
317                                     ~r.ir_free) {
318                                 /*
319                                  * Grab the chunk record.  Mark all the
320                                  * uninteresting inodes (because they're
321                                  * before our start point) free.
322                                  */
323                                 for (i = 0; i < chunkidx; i++) {
324                                         if (XFS_INOBT_MASK(i) & ~r.ir_free)
325                                                 r.ir_freecount++;
326                                 }
327                                 r.ir_free |= xfs_inobt_maskn(0, chunkidx);
328                                 irbp->ir_startino = r.ir_startino;
329                                 irbp->ir_freecount = r.ir_freecount;
330                                 irbp->ir_free = r.ir_free;
331                                 irbp++;
332                                 agino = r.ir_startino + XFS_INODES_PER_CHUNK;
333                                 icount = XFS_INODES_PER_CHUNK - r.ir_freecount;
334                         } else {
335                                 /*
336                                  * If any of those tests failed, bump the
337                                  * inode number (just in case).
338                                  */
339                                 agino++;
340                                 icount = 0;
341                         }
342                         /*
343                          * In any case, increment to the next record.
344                          */
345                         if (!error)
346                                 error = xfs_btree_increment(cur, 0, &tmp);
347                 } else {
348                         /*
349                          * Start of ag.  Lookup the first inode chunk.
350                          */
351                         error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);
352                         icount = 0;
353                 }
354                 /*
355                  * Loop through inode btree records in this ag,
356                  * until we run out of inodes or space in the buffer.
357                  */
358                 while (irbp < irbufend && icount < ubcount) {
359                         xfs_inobt_rec_incore_t r;
360
361                         /*
362                          * Loop as long as we're unable to read the
363                          * inode btree.
364                          */
365                         while (error) {
366                                 agino += XFS_INODES_PER_CHUNK;
367                                 if (XFS_AGINO_TO_AGBNO(mp, agino) >=
368                                                 be32_to_cpu(agi->agi_length))
369                                         break;
370                                 error = xfs_inobt_lookup(cur, agino,
371                                                          XFS_LOOKUP_GE, &tmp);
372                                 cond_resched();
373                         }
374                         /*
375                          * If ran off the end of the ag either with an error,
376                          * or the normal way, set end and stop collecting.
377                          */
378                         if (error) {
379                                 end_of_ag = 1;
380                                 break;
381                         }
382
383                         error = xfs_inobt_get_rec(cur, &r, &i);
384                         if (error || i == 0) {
385                                 end_of_ag = 1;
386                                 break;
387                         }
388
389                         /*
390                          * If this chunk has any allocated inodes, save it.
391                          * Also start read-ahead now for this chunk.
392                          */
393                         if (r.ir_freecount < XFS_INODES_PER_CHUNK) {
394                                 /*
395                                  * Loop over all clusters in the next chunk.
396                                  * Do a readahead if there are any allocated
397                                  * inodes in that cluster.
398                                  */
399                                 agbno = XFS_AGINO_TO_AGBNO(mp, r.ir_startino);
400                                 for (chunkidx = 0;
401                                      chunkidx < XFS_INODES_PER_CHUNK;
402                                      chunkidx += nicluster,
403                                      agbno += nbcluster) {
404                                         if (xfs_inobt_maskn(chunkidx, nicluster)
405                                                         & ~r.ir_free)
406                                                 xfs_btree_reada_bufs(mp, agno,
407                                                         agbno, nbcluster);
408                                 }
409                                 irbp->ir_startino = r.ir_startino;
410                                 irbp->ir_freecount = r.ir_freecount;
411                                 irbp->ir_free = r.ir_free;
412                                 irbp++;
413                                 icount += XFS_INODES_PER_CHUNK - r.ir_freecount;
414                         }
415                         /*
416                          * Set agino to after this chunk and bump the cursor.
417                          */
418                         agino = r.ir_startino + XFS_INODES_PER_CHUNK;
419                         error = xfs_btree_increment(cur, 0, &tmp);
420                         cond_resched();
421                 }
422                 /*
423                  * Drop the btree buffers and the agi buffer.
424                  * We can't hold any of the locks these represent
425                  * when calling iget.
426                  */
427                 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
428                 xfs_buf_relse(agbp);
429                 /*
430                  * Now format all the good inodes into the user's buffer.
431                  */
432                 irbufend = irbp;
433                 for (irbp = irbuf;
434                      irbp < irbufend && XFS_BULKSTAT_UBLEFT(ubleft); irbp++) {
435                         /*
436                          * Now process this chunk of inodes.
437                          */
438                         for (agino = irbp->ir_startino, chunkidx = clustidx = 0;
439                              XFS_BULKSTAT_UBLEFT(ubleft) &&
440                                 irbp->ir_freecount < XFS_INODES_PER_CHUNK;
441                              chunkidx++, clustidx++, agino++) {
442                                 ASSERT(chunkidx < XFS_INODES_PER_CHUNK);
443                                 /*
444                                  * Recompute agbno if this is the
445                                  * first inode of the cluster.
446                                  *
447                                  * Careful with clustidx.   There can be
448                                  * multiple clusters per chunk, a single
449                                  * cluster per chunk or a cluster that has
450                                  * inodes represented from several different
451                                  * chunks (if blocksize is large).
452                                  *
453                                  * Because of this, the starting clustidx is
454                                  * initialized to zero in this loop but must
455                                  * later be reset after reading in the cluster
456                                  * buffer.
457                                  */
458                                 if ((chunkidx & (nicluster - 1)) == 0) {
459                                         agbno = XFS_AGINO_TO_AGBNO(mp,
460                                                         irbp->ir_startino) +
461                                                 ((chunkidx & nimask) >>
462                                                  mp->m_sb.sb_inopblog);
463                                 }
464                                 ino = XFS_AGINO_TO_INO(mp, agno, agino);
465                                 bno = XFS_AGB_TO_DADDR(mp, agno, agbno);
466                                 /*
467                                  * Skip if this inode is free.
468                                  */
469                                 if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) {
470                                         lastino = ino;
471                                         continue;
472                                 }
473                                 /*
474                                  * Count used inodes as free so we can tell
475                                  * when the chunk is used up.
476                                  */
477                                 irbp->ir_freecount++;
478
479                                 /*
480                                  * Get the inode and fill in a single buffer.
481                                  */
482                                 ubused = statstruct_size;
483                                 error = formatter(mp, ino, ubufp, ubleft,
484                                                   &ubused, &fmterror);
485                                 if (fmterror == BULKSTAT_RV_NOTHING) {
486                                         if (error && error != ENOENT &&
487                                                 error != EINVAL) {
488                                                 ubleft = 0;
489                                                 rval = error;
490                                                 break;
491                                         }
492                                         lastino = ino;
493                                         continue;
494                                 }
495                                 if (fmterror == BULKSTAT_RV_GIVEUP) {
496                                         ubleft = 0;
497                                         ASSERT(error);
498                                         rval = error;
499                                         break;
500                                 }
501                                 if (ubufp)
502                                         ubufp += ubused;
503                                 ubleft -= ubused;
504                                 ubelem++;
505                                 lastino = ino;
506                         }
507
508                         cond_resched();
509                 }
510
511                 if (bp)
512                         xfs_buf_relse(bp);
513
514                 /*
515                  * Set up for the next loop iteration.
516                  */
517                 if (XFS_BULKSTAT_UBLEFT(ubleft)) {
518                         if (end_of_ag) {
519                                 agno++;
520                                 agino = 0;
521                         } else
522                                 agino = XFS_INO_TO_AGINO(mp, lastino);
523                 } else
524                         break;
525         }
526         /*
527          * Done, we're either out of filesystem or space to put the data.
528          */
529         kmem_free_large(irbuf);
530         *ubcountp = ubelem;
531         /*
532          * Found some inodes, return them now and return the error next time.
533          */
534         if (ubelem)
535                 rval = 0;
536         if (agno >= mp->m_sb.sb_agcount) {
537                 /*
538                  * If we ran out of filesystem, mark lastino as off
539                  * the end of the filesystem, so the next call
540                  * will return immediately.
541                  */
542                 *lastinop = (xfs_ino_t)XFS_AGINO_TO_INO(mp, agno, 0);
543                 *done = 1;
544         } else
545                 *lastinop = (xfs_ino_t)lastino;
546
547         return rval;
548 }
549
550 /*
551  * Return stat information in bulk (by-inode) for the filesystem.
552  * Special case for non-sequential one inode bulkstat.
553  */
554 int                                     /* error status */
555 xfs_bulkstat_single(
556         xfs_mount_t             *mp,    /* mount point for filesystem */
557         xfs_ino_t               *lastinop, /* inode to return */
558         char                    __user *buffer, /* buffer with inode stats */
559         int                     *done)  /* 1 if there are more stats to get */
560 {
561         int                     count;  /* count value for bulkstat call */
562         int                     error;  /* return value */
563         xfs_ino_t               ino;    /* filesystem inode number */
564         int                     res;    /* result from bs1 */
565
566         /*
567          * note that requesting valid inode numbers which are not allocated
568          * to inodes will most likely cause xfs_itobp to generate warning
569          * messages about bad magic numbers. This is ok. The fact that
570          * the inode isn't actually an inode is handled by the
571          * error check below. Done this way to make the usual case faster
572          * at the expense of the error case.
573          */
574
575         ino = (xfs_ino_t)*lastinop;
576         error = xfs_bulkstat_one(mp, ino, buffer, sizeof(xfs_bstat_t), 0, &res);
577         if (error) {
578                 /*
579                  * Special case way failed, do it the "long" way
580                  * to see if that works.
581                  */
582                 (*lastinop)--;
583                 count = 1;
584                 if (xfs_bulkstat(mp, lastinop, &count, xfs_bulkstat_one,
585                                 sizeof(xfs_bstat_t), buffer, done))
586                         return error;
587                 if (count == 0 || (xfs_ino_t)*lastinop != ino)
588                         return error == EFSCORRUPTED ?
589                                 XFS_ERROR(EINVAL) : error;
590                 else
591                         return 0;
592         }
593         *done = 0;
594         return 0;
595 }
596
597 int
598 xfs_inumbers_fmt(
599         void                    __user *ubuffer, /* buffer to write to */
600         const xfs_inogrp_t      *buffer,        /* buffer to read from */
601         long                    count,          /* # of elements to read */
602         long                    *written)       /* # of bytes written */
603 {
604         if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
605                 return -EFAULT;
606         *written = count * sizeof(*buffer);
607         return 0;
608 }
609
610 /*
611  * Return inode number table for the filesystem.
612  */
613 int                                     /* error status */
614 xfs_inumbers(
615         xfs_mount_t     *mp,            /* mount point for filesystem */
616         xfs_ino_t       *lastino,       /* last inode returned */
617         int             *count,         /* size of buffer/count returned */
618         void            __user *ubuffer,/* buffer with inode descriptions */
619         inumbers_fmt_pf formatter)
620 {
621         xfs_buf_t       *agbp;
622         xfs_agino_t     agino;
623         xfs_agnumber_t  agno;
624         int             bcount;
625         xfs_inogrp_t    *buffer;
626         int             bufidx;
627         xfs_btree_cur_t *cur;
628         int             error;
629         xfs_inobt_rec_incore_t r;
630         int             i;
631         xfs_ino_t       ino;
632         int             left;
633         int             tmp;
634
635         ino = (xfs_ino_t)*lastino;
636         agno = XFS_INO_TO_AGNO(mp, ino);
637         agino = XFS_INO_TO_AGINO(mp, ino);
638         left = *count;
639         *count = 0;
640         bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
641         buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
642         error = bufidx = 0;
643         cur = NULL;
644         agbp = NULL;
645         while (left > 0 && agno < mp->m_sb.sb_agcount) {
646                 if (agbp == NULL) {
647                         error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
648                         if (error) {
649                                 /*
650                                  * If we can't read the AGI of this ag,
651                                  * then just skip to the next one.
652                                  */
653                                 ASSERT(cur == NULL);
654                                 agbp = NULL;
655                                 agno++;
656                                 agino = 0;
657                                 continue;
658                         }
659                         cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
660                         error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
661                                                  &tmp);
662                         if (error) {
663                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
664                                 cur = NULL;
665                                 xfs_buf_relse(agbp);
666                                 agbp = NULL;
667                                 /*
668                                  * Move up the last inode in the current
669                                  * chunk.  The lookup_ge will always get
670                                  * us the first inode in the next chunk.
671                                  */
672                                 agino += XFS_INODES_PER_CHUNK - 1;
673                                 continue;
674                         }
675                 }
676                 error = xfs_inobt_get_rec(cur, &r, &i);
677                 if (error || i == 0) {
678                         xfs_buf_relse(agbp);
679                         agbp = NULL;
680                         xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
681                         cur = NULL;
682                         agno++;
683                         agino = 0;
684                         continue;
685                 }
686                 agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
687                 buffer[bufidx].xi_startino =
688                         XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
689                 buffer[bufidx].xi_alloccount =
690                         XFS_INODES_PER_CHUNK - r.ir_freecount;
691                 buffer[bufidx].xi_allocmask = ~r.ir_free;
692                 bufidx++;
693                 left--;
694                 if (bufidx == bcount) {
695                         long written;
696                         if (formatter(ubuffer, buffer, bufidx, &written)) {
697                                 error = XFS_ERROR(EFAULT);
698                                 break;
699                         }
700                         ubuffer += written;
701                         *count += bufidx;
702                         bufidx = 0;
703                 }
704                 if (left) {
705                         error = xfs_btree_increment(cur, 0, &tmp);
706                         if (error) {
707                                 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
708                                 cur = NULL;
709                                 xfs_buf_relse(agbp);
710                                 agbp = NULL;
711                                 /*
712                                  * The agino value has already been bumped.
713                                  * Just try to skip up to it.
714                                  */
715                                 agino += XFS_INODES_PER_CHUNK;
716                                 continue;
717                         }
718                 }
719         }
720         if (!error) {
721                 if (bufidx) {
722                         long written;
723                         if (formatter(ubuffer, buffer, bufidx, &written))
724                                 error = XFS_ERROR(EFAULT);
725                         else
726                                 *count += bufidx;
727                 }
728                 *lastino = XFS_AGINO_TO_INO(mp, agno, agino);
729         }
730         kmem_free(buffer);
731         if (cur)
732                 xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
733                                            XFS_BTREE_NOERROR));
734         if (agbp)
735                 xfs_buf_relse(agbp);
736         return error;
737 }