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