git.oblomov.eu Git - linux-2.6/blob - fs/xfs/xfs_dir2_block.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 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_log.h"
  22 #include "xfs_inum.h"
  23 #include "xfs_trans.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_dir2.h"
  26 #include "xfs_dmapi.h"
  27 #include "xfs_mount.h"
  28 #include "xfs_da_btree.h"
  29 #include "xfs_bmap_btree.h"
  30 #include "xfs_dir2_sf.h"
  31 #include "xfs_attr_sf.h"
  32 #include "xfs_dinode.h"
  33 #include "xfs_inode.h"
  34 #include "xfs_inode_item.h"
  35 #include "xfs_dir2_data.h"
  36 #include "xfs_dir2_leaf.h"
  37 #include "xfs_dir2_block.h"
  38 #include "xfs_dir2_trace.h"
  39 #include "xfs_error.h"
  40
  41 /*
  42  * Local function prototypes.
  43  */
  44 static void xfs_dir2_block_log_leaf(xfs_trans_t *tp, xfs_dabuf_t *bp, int first,
  45                                     int last);
  46 static void xfs_dir2_block_log_tail(xfs_trans_t *tp, xfs_dabuf_t *bp);
  47 static int xfs_dir2_block_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **bpp,
  48                                      int *entno);
  49 static int xfs_dir2_block_sort(const void *a, const void *b);
  50
  51 static xfs_dahash_t xfs_dir_hash_dot, xfs_dir_hash_dotdot;
  52
  53 /*
  54  * One-time startup routine called from xfs_init().
  55  */
  56 void
  57 xfs_dir_startup(void)
  58 {
  59         xfs_dir_hash_dot = xfs_da_hashname(".", 1);
  60         xfs_dir_hash_dotdot = xfs_da_hashname("..", 2);
  61 }
  62
  63 /*
  64  * Add an entry to a block directory.
  65  */
  66 int                                             /* error */
  67 xfs_dir2_block_addname(
  68         xfs_da_args_t           *args)          /* directory op arguments */
  69 {
  70         xfs_dir2_data_free_t    *bf;            /* bestfree table in block */
  71         xfs_dir2_block_t        *block;         /* directory block structure */
  72         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
  73         xfs_dabuf_t             *bp;            /* buffer for block */
  74         xfs_dir2_block_tail_t   *btp;           /* block tail */
  75         int                     compact;        /* need to compact leaf ents */
  76         xfs_dir2_data_entry_t   *dep;           /* block data entry */
  77         xfs_inode_t             *dp;            /* directory inode */
  78         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
  79         int                     error;          /* error return value */
  80         xfs_dir2_data_unused_t  *enddup=NULL;   /* unused at end of data */
  81         xfs_dahash_t            hash;           /* hash value of found entry */
  82         int                     high;           /* high index for binary srch */
  83         int                     highstale;      /* high stale index */
  84         int                     lfloghigh=0;    /* last final leaf to log */
  85         int                     lfloglow=0;     /* first final leaf to log */
  86         int                     len;            /* length of the new entry */
  87         int                     low;            /* low index for binary srch */
  88         int                     lowstale;       /* low stale index */
  89         int                     mid=0;          /* midpoint for binary srch */
  90         xfs_mount_t             *mp;            /* filesystem mount point */
  91         int                     needlog;        /* need to log header */
  92         int                     needscan;       /* need to rescan freespace */
  93         __be16                  *tagp;          /* pointer to tag value */
  94         xfs_trans_t             *tp;            /* transaction structure */
  95
  96         xfs_dir2_trace_args("block_addname", args);
  97         dp = args->dp;
  98         tp = args->trans;
  99         mp = dp->i_mount;
 100         /*
 101          * Read the (one and only) directory block into dabuf bp.
 102          */
 103         if ((error =
 104             xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &bp, XFS_DATA_FORK))) {
 105                 return error;
 106         }
 107         ASSERT(bp != NULL);
 108         block = bp->data;
 109         /*
 110          * Check the magic number, corrupted if wrong.
 111          */
 112         if (unlikely(be32_to_cpu(block->hdr.magic) != XFS_DIR2_BLOCK_MAGIC)) {
 113                 XFS_CORRUPTION_ERROR("xfs_dir2_block_addname",
 114                                      XFS_ERRLEVEL_LOW, mp, block);
 115                 xfs_da_brelse(tp, bp);
 116                 return XFS_ERROR(EFSCORRUPTED);
 117         }
 118         len = xfs_dir2_data_entsize(args->namelen);
 119         /*
 120          * Set up pointers to parts of the block.
 121          */
 122         bf = block->hdr.bestfree;
 123         btp = xfs_dir2_block_tail_p(mp, block);
 124         blp = xfs_dir2_block_leaf_p(btp);
 125         /*
 126          * No stale entries?  Need space for entry and new leaf.
 127          */
 128         if (!btp->stale) {
 129                 /*
 130                  * Tag just before the first leaf entry.
 131                  */
 132                 tagp = (__be16 *)blp - 1;
 133                 /*
 134                  * Data object just before the first leaf entry.
 135                  */
 136                 enddup = (xfs_dir2_data_unused_t *)((char *)block + be16_to_cpu(*tagp));
 137                 /*
 138                  * If it's not free then can't do this add without cleaning up:
 139                  * the space before the first leaf entry needs to be free so it
 140                  * can be expanded to hold the pointer to the new entry.
 141                  */
 142                 if (be16_to_cpu(enddup->freetag) != XFS_DIR2_DATA_FREE_TAG)
 143                         dup = enddup = NULL;
 144                 /*
 145                  * Check out the biggest freespace and see if it's the same one.
 146                  */
 147                 else {
 148                         dup = (xfs_dir2_data_unused_t *)
 149                               ((char *)block + be16_to_cpu(bf[0].offset));
 150                         if (dup == enddup) {
 151                                 /*
 152                                  * It is the biggest freespace, is it too small
 153                                  * to hold the new leaf too?
 154                                  */
 155                                 if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
 156                                         /*
 157                                          * Yes, we use the second-largest
 158                                          * entry instead if it works.
 159                                          */
 160                                         if (be16_to_cpu(bf[1].length) >= len)
 161                                                 dup = (xfs_dir2_data_unused_t *)
 162                                                       ((char *)block +
 163                                                        be16_to_cpu(bf[1].offset));
 164                                         else
 165                                                 dup = NULL;
 166                                 }
 167                         } else {
 168                                 /*
 169                                  * Not the same free entry,
 170                                  * just check its length.
 171                                  */
 172                                 if (be16_to_cpu(dup->length) < len) {
 173                                         dup = NULL;
 174                                 }
 175                         }
 176                 }
 177                 compact = 0;
 178         }
 179         /*
 180          * If there are stale entries we'll use one for the leaf.
 181          * Is the biggest entry enough to avoid compaction?
 182          */
 183         else if (be16_to_cpu(bf[0].length) >= len) {
 184                 dup = (xfs_dir2_data_unused_t *)
 185                       ((char *)block + be16_to_cpu(bf[0].offset));
 186                 compact = 0;
 187         }
 188         /*
 189          * Will need to compact to make this work.
 190          */
 191         else {
 192                 /*
 193                  * Tag just before the first leaf entry.
 194                  */
 195                 tagp = (__be16 *)blp - 1;
 196                 /*
 197                  * Data object just before the first leaf entry.
 198                  */
 199                 dup = (xfs_dir2_data_unused_t *)((char *)block + be16_to_cpu(*tagp));
 200                 /*
 201                  * If it's not free then the data will go where the
 202                  * leaf data starts now, if it works at all.
 203                  */
 204                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 205                         if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
 206                             (uint)sizeof(*blp) < len)
 207                                 dup = NULL;
 208                 } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
 209                         dup = NULL;
 210                 else
 211                         dup = (xfs_dir2_data_unused_t *)blp;
 212                 compact = 1;
 213         }
 214         /*
 215          * If this isn't a real add, we're done with the buffer.
 216          */
 217         if (args->justcheck)
 218                 xfs_da_brelse(tp, bp);
 219         /*
 220          * If we don't have space for the new entry & leaf ...
 221          */
 222         if (!dup) {
 223                 /*
 224                  * Not trying to actually do anything, or don't have
 225                  * a space reservation: return no-space.
 226                  */
 227                 if (args->justcheck || args->total == 0)
 228                         return XFS_ERROR(ENOSPC);
 229                 /*
 230                  * Convert to the next larger format.
 231                  * Then add the new entry in that format.
 232                  */
 233                 error = xfs_dir2_block_to_leaf(args, bp);
 234                 xfs_da_buf_done(bp);
 235                 if (error)
 236                         return error;
 237                 return xfs_dir2_leaf_addname(args);
 238         }
 239         /*
 240          * Just checking, and it would work, so say so.
 241          */
 242         if (args->justcheck)
 243                 return 0;
 244         needlog = needscan = 0;
 245         /*
 246          * If need to compact the leaf entries, do it now.
 247          * Leave the highest-numbered stale entry stale.
 248          * XXX should be the one closest to mid but mid is not yet computed.
 249          */
 250         if (compact) {
 251                 int     fromidx;                /* source leaf index */
 252                 int     toidx;                  /* target leaf index */
 253
 254                 for (fromidx = toidx = be32_to_cpu(btp->count) - 1,
 255                         highstale = lfloghigh = -1;
 256                      fromidx >= 0;
 257                      fromidx--) {
 258                         if (be32_to_cpu(blp[fromidx].address) == XFS_DIR2_NULL_DATAPTR) {
 259                                 if (highstale == -1)
 260                                         highstale = toidx;
 261                                 else {
 262                                         if (lfloghigh == -1)
 263                                                 lfloghigh = toidx;
 264                                         continue;
 265                                 }
 266                         }
 267                         if (fromidx < toidx)
 268                                 blp[toidx] = blp[fromidx];
 269                         toidx--;
 270                 }
 271                 lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
 272                 lfloghigh -= be32_to_cpu(btp->stale) - 1;
 273                 be32_add(&btp->count, -(be32_to_cpu(btp->stale) - 1));
 274                 xfs_dir2_data_make_free(tp, bp,
 275                         (xfs_dir2_data_aoff_t)((char *)blp - (char *)block),
 276                         (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
 277                         &needlog, &needscan);
 278                 blp += be32_to_cpu(btp->stale) - 1;
 279                 btp->stale = cpu_to_be32(1);
 280                 /*
 281                  * If we now need to rebuild the bestfree map, do so.
 282                  * This needs to happen before the next call to use_free.
 283                  */
 284                 if (needscan) {
 285                         xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
 286                         needscan = 0;
 287                 }
 288         }
 289         /*
 290          * Set leaf logging boundaries to impossible state.
 291          * For the no-stale case they're set explicitly.
 292          */
 293         else if (btp->stale) {
 294                 lfloglow = be32_to_cpu(btp->count);
 295                 lfloghigh = -1;
 296         }
 297         /*
 298          * Find the slot that's first lower than our hash value, -1 if none.
 299          */
 300         for (low = 0, high = be32_to_cpu(btp->count) - 1; low <= high; ) {
 301                 mid = (low + high) >> 1;
 302                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 303                         break;
 304                 if (hash < args->hashval)
 305                         low = mid + 1;
 306                 else
 307                         high = mid - 1;
 308         }
 309         while (mid >= 0 && be32_to_cpu(blp[mid].hashval) >= args->hashval) {
 310                 mid--;
 311         }
 312         /*
 313          * No stale entries, will use enddup space to hold new leaf.
 314          */
 315         if (!btp->stale) {
 316                 /*
 317                  * Mark the space needed for the new leaf entry, now in use.
 318                  */
 319                 xfs_dir2_data_use_free(tp, bp, enddup,
 320                         (xfs_dir2_data_aoff_t)
 321                         ((char *)enddup - (char *)block + be16_to_cpu(enddup->length) -
 322                          sizeof(*blp)),
 323                         (xfs_dir2_data_aoff_t)sizeof(*blp),
 324                         &needlog, &needscan);
 325                 /*
 326                  * Update the tail (entry count).
 327                  */
 328                 be32_add(&btp->count, 1);
 329                 /*
 330                  * If we now need to rebuild the bestfree map, do so.
 331                  * This needs to happen before the next call to use_free.
 332                  */
 333                 if (needscan) {
 334                         xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block,
 335                                 &needlog);
 336                         needscan = 0;
 337                 }
 338                 /*
 339                  * Adjust pointer to the first leaf entry, we're about to move
 340                  * the table up one to open up space for the new leaf entry.
 341                  * Then adjust our index to match.
 342                  */
 343                 blp--;
 344                 mid++;
 345                 if (mid)
 346                         memmove(blp, &blp[1], mid * sizeof(*blp));
 347                 lfloglow = 0;
 348                 lfloghigh = mid;
 349         }
 350         /*
 351          * Use a stale leaf for our new entry.
 352          */
 353         else {
 354                 for (lowstale = mid;
 355                      lowstale >= 0 &&
 356                         be32_to_cpu(blp[lowstale].address) != XFS_DIR2_NULL_DATAPTR;
 357                      lowstale--)
 358                         continue;
 359                 for (highstale = mid + 1;
 360                      highstale < be32_to_cpu(btp->count) &&
 361                         be32_to_cpu(blp[highstale].address) != XFS_DIR2_NULL_DATAPTR &&
 362                         (lowstale < 0 || mid - lowstale > highstale - mid);
 363                      highstale++)
 364                         continue;
 365                 /*
 366                  * Move entries toward the low-numbered stale entry.
 367                  */
 368                 if (lowstale >= 0 &&
 369                     (highstale == be32_to_cpu(btp->count) ||
 370                      mid - lowstale <= highstale - mid)) {
 371                         if (mid - lowstale)
 372                                 memmove(&blp[lowstale], &blp[lowstale + 1],
 373                                         (mid - lowstale) * sizeof(*blp));
 374                         lfloglow = MIN(lowstale, lfloglow);
 375                         lfloghigh = MAX(mid, lfloghigh);
 376                 }
 377                 /*
 378                  * Move entries toward the high-numbered stale entry.
 379                  */
 380                 else {
 381                         ASSERT(highstale < be32_to_cpu(btp->count));
 382                         mid++;
 383                         if (highstale - mid)
 384                                 memmove(&blp[mid + 1], &blp[mid],
 385                                         (highstale - mid) * sizeof(*blp));
 386                         lfloglow = MIN(mid, lfloglow);
 387                         lfloghigh = MAX(highstale, lfloghigh);
 388                 }
 389                 be32_add(&btp->stale, -1);
 390         }
 391         /*
 392          * Point to the new data entry.
 393          */
 394         dep = (xfs_dir2_data_entry_t *)dup;
 395         /*
 396          * Fill in the leaf entry.
 397          */
 398         blp[mid].hashval = cpu_to_be32(args->hashval);
 399         blp[mid].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
 400                                 (char *)dep - (char *)block));
 401         xfs_dir2_block_log_leaf(tp, bp, lfloglow, lfloghigh);
 402         /*
 403          * Mark space for the data entry used.
 404          */
 405         xfs_dir2_data_use_free(tp, bp, dup,
 406                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)block),
 407                 (xfs_dir2_data_aoff_t)len, &needlog, &needscan);
 408         /*
 409          * Create the new data entry.
 410          */
 411         dep->inumber = cpu_to_be64(args->inumber);
 412         dep->namelen = args->namelen;
 413         memcpy(dep->name, args->name, args->namelen);
 414         tagp = xfs_dir2_data_entry_tag_p(dep);
 415         *tagp = cpu_to_be16((char *)dep - (char *)block);
 416         /*
 417          * Clean up the bestfree array and log the header, tail, and entry.
 418          */
 419         if (needscan)
 420                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
 421         if (needlog)
 422                 xfs_dir2_data_log_header(tp, bp);
 423         xfs_dir2_block_log_tail(tp, bp);
 424         xfs_dir2_data_log_entry(tp, bp, dep);
 425         xfs_dir2_data_check(dp, bp);
 426         xfs_da_buf_done(bp);
 427         return 0;
 428 }
 429
 430 /*
 431  * Readdir for block directories.
 432  */
 433 int                                             /* error */
 434 xfs_dir2_block_getdents(
 435         xfs_trans_t             *tp,            /* transaction (NULL) */
 436         xfs_inode_t             *dp,            /* incore inode */
 437         uio_t                   *uio,           /* caller's buffer control */
 438         int                     *eofp,          /* eof reached? (out) */
 439         xfs_dirent_t            *dbp,           /* caller's buffer */
 440         xfs_dir2_put_t          put)            /* abi's formatting function */
 441 {
 442         xfs_dir2_block_t        *block;         /* directory block structure */
 443         xfs_dabuf_t             *bp;            /* buffer for block */
 444         xfs_dir2_block_tail_t   *btp;           /* block tail */
 445         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 446         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 447         char                    *endptr;        /* end of the data entries */
 448         int                     error;          /* error return value */
 449         xfs_mount_t             *mp;            /* filesystem mount point */
 450         xfs_dir2_put_args_t     p;              /* arg package for put rtn */
 451         char                    *ptr;           /* current data entry */
 452         int                     wantoff;        /* starting block offset */
 453
 454         mp = dp->i_mount;
 455         /*
 456          * If the block number in the offset is out of range, we're done.
 457          */
 458         if (xfs_dir2_dataptr_to_db(mp, uio->uio_offset) > mp->m_dirdatablk) {
 459                 *eofp = 1;
 460                 return 0;
 461         }
 462         /*
 463          * Can't read the block, give up, else get dabuf in bp.
 464          */
 465         if ((error =
 466             xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &bp, XFS_DATA_FORK))) {
 467                 return error;
 468         }
 469         ASSERT(bp != NULL);
 470         /*
 471          * Extract the byte offset we start at from the seek pointer.
 472          * We'll skip entries before this.
 473          */
 474         wantoff = xfs_dir2_dataptr_to_off(mp, uio->uio_offset);
 475         block = bp->data;
 476         xfs_dir2_data_check(dp, bp);
 477         /*
 478          * Set up values for the loop.
 479          */
 480         btp = xfs_dir2_block_tail_p(mp, block);
 481         ptr = (char *)block->u;
 482         endptr = (char *)xfs_dir2_block_leaf_p(btp);
 483         p.dbp = dbp;
 484         p.put = put;
 485         p.uio = uio;
 486         /*
 487          * Loop over the data portion of the block.
 488          * Each object is a real entry (dep) or an unused one (dup).
 489          */
 490         while (ptr < endptr) {
 491                 dup = (xfs_dir2_data_unused_t *)ptr;
 492                 /*
 493                  * Unused, skip it.
 494                  */
 495                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 496                         ptr += be16_to_cpu(dup->length);
 497                         continue;
 498                 }
 499
 500                 dep = (xfs_dir2_data_entry_t *)ptr;
 501
 502                 /*
 503                  * Bump pointer for the next iteration.
 504                  */
 505                 ptr += xfs_dir2_data_entsize(dep->namelen);
 506                 /*
 507                  * The entry is before the desired starting point, skip it.
 508                  */
 509                 if ((char *)dep - (char *)block < wantoff)
 510                         continue;
 511                 /*
 512                  * Set up argument structure for put routine.
 513                  */
 514                 p.namelen = dep->namelen;
 515
 516                 p.cook = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
 517                                                     ptr - (char *)block);
 518                 p.ino = be64_to_cpu(dep->inumber);
 519 #if XFS_BIG_INUMS
 520                 p.ino += mp->m_inoadd;
 521 #endif
 522                 p.name = (char *)dep->name;
 523
 524                 /*
 525                  * Put the entry in the caller's buffer.
 526                  */
 527                 error = p.put(&p);
 528
 529                 /*
 530                  * If it didn't fit, set the final offset to here & return.
 531                  */
 532                 if (!p.done) {
 533                         uio->uio_offset =
 534                                 xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
 535                                         (char *)dep - (char *)block);
 536                         xfs_da_brelse(tp, bp);
 537                         return error;
 538                 }
 539         }
 540
 541         /*
 542          * Reached the end of the block.
 543          * Set the offset to a non-existent block 1 and return.
 544          */
 545         *eofp = 1;
 546
 547         uio->uio_offset =
 548                 xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk + 1, 0);
 549
 550         xfs_da_brelse(tp, bp);
 551
 552         return 0;
 553 }
 554
 555 /*
 556  * Log leaf entries from the block.
 557  */
 558 static void
 559 xfs_dir2_block_log_leaf(
 560         xfs_trans_t             *tp,            /* transaction structure */
 561         xfs_dabuf_t             *bp,            /* block buffer */
 562         int                     first,          /* index of first logged leaf */
 563         int                     last)           /* index of last logged leaf */
 564 {
 565         xfs_dir2_block_t        *block;         /* directory block structure */
 566         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 567         xfs_dir2_block_tail_t   *btp;           /* block tail */
 568         xfs_mount_t             *mp;            /* filesystem mount point */
 569
 570         mp = tp->t_mountp;
 571         block = bp->data;
 572         btp = xfs_dir2_block_tail_p(mp, block);
 573         blp = xfs_dir2_block_leaf_p(btp);
 574         xfs_da_log_buf(tp, bp, (uint)((char *)&blp[first] - (char *)block),
 575                 (uint)((char *)&blp[last + 1] - (char *)block - 1));
 576 }
 577
 578 /*
 579  * Log the block tail.
 580  */
 581 static void
 582 xfs_dir2_block_log_tail(
 583         xfs_trans_t             *tp,            /* transaction structure */
 584         xfs_dabuf_t             *bp)            /* block buffer */
 585 {
 586         xfs_dir2_block_t        *block;         /* directory block structure */
 587         xfs_dir2_block_tail_t   *btp;           /* block tail */
 588         xfs_mount_t             *mp;            /* filesystem mount point */
 589
 590         mp = tp->t_mountp;
 591         block = bp->data;
 592         btp = xfs_dir2_block_tail_p(mp, block);
 593         xfs_da_log_buf(tp, bp, (uint)((char *)btp - (char *)block),
 594                 (uint)((char *)(btp + 1) - (char *)block - 1));
 595 }
 596
 597 /*
 598  * Look up an entry in the block.  This is the external routine,
 599  * xfs_dir2_block_lookup_int does the real work.
 600  */
 601 int                                             /* error */
 602 xfs_dir2_block_lookup(
 603         xfs_da_args_t           *args)          /* dir lookup arguments */
 604 {
 605         xfs_dir2_block_t        *block;         /* block structure */
 606         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 607         xfs_dabuf_t             *bp;            /* block buffer */
 608         xfs_dir2_block_tail_t   *btp;           /* block tail */
 609         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 610         xfs_inode_t             *dp;            /* incore inode */
 611         int                     ent;            /* entry index */
 612         int                     error;          /* error return value */
 613         xfs_mount_t             *mp;            /* filesystem mount point */
 614
 615         xfs_dir2_trace_args("block_lookup", args);
 616         /*
 617          * Get the buffer, look up the entry.
 618          * If not found (ENOENT) then return, have no buffer.
 619          */
 620         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent)))
 621                 return error;
 622         dp = args->dp;
 623         mp = dp->i_mount;
 624         block = bp->data;
 625         xfs_dir2_data_check(dp, bp);
 626         btp = xfs_dir2_block_tail_p(mp, block);
 627         blp = xfs_dir2_block_leaf_p(btp);
 628         /*
 629          * Get the offset from the leaf entry, to point to the data.
 630          */
 631         dep = (xfs_dir2_data_entry_t *)
 632               ((char *)block + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 633         /*
 634          * Fill in inode number, release the block.
 635          */
 636         args->inumber = be64_to_cpu(dep->inumber);
 637         xfs_da_brelse(args->trans, bp);
 638         return XFS_ERROR(EEXIST);
 639 }
 640
 641 /*
 642  * Internal block lookup routine.
 643  */
 644 static int                                      /* error */
 645 xfs_dir2_block_lookup_int(
 646         xfs_da_args_t           *args,          /* dir lookup arguments */
 647         xfs_dabuf_t             **bpp,          /* returned block buffer */
 648         int                     *entno)         /* returned entry number */
 649 {
 650         xfs_dir2_dataptr_t      addr;           /* data entry address */
 651         xfs_dir2_block_t        *block;         /* block structure */
 652         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 653         xfs_dabuf_t             *bp;            /* block buffer */
 654         xfs_dir2_block_tail_t   *btp;           /* block tail */
 655         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 656         xfs_inode_t             *dp;            /* incore inode */
 657         int                     error;          /* error return value */
 658         xfs_dahash_t            hash;           /* found hash value */
 659         int                     high;           /* binary search high index */
 660         int                     low;            /* binary search low index */
 661         int                     mid;            /* binary search current idx */
 662         xfs_mount_t             *mp;            /* filesystem mount point */
 663         xfs_trans_t             *tp;            /* transaction pointer */
 664
 665         dp = args->dp;
 666         tp = args->trans;
 667         mp = dp->i_mount;
 668         /*
 669          * Read the buffer, return error if we can't get it.
 670          */
 671         if ((error =
 672             xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &bp, XFS_DATA_FORK))) {
 673                 return error;
 674         }
 675         ASSERT(bp != NULL);
 676         block = bp->data;
 677         xfs_dir2_data_check(dp, bp);
 678         btp = xfs_dir2_block_tail_p(mp, block);
 679         blp = xfs_dir2_block_leaf_p(btp);
 680         /*
 681          * Loop doing a binary search for our hash value.
 682          * Find our entry, ENOENT if it's not there.
 683          */
 684         for (low = 0, high = be32_to_cpu(btp->count) - 1; ; ) {
 685                 ASSERT(low <= high);
 686                 mid = (low + high) >> 1;
 687                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 688                         break;
 689                 if (hash < args->hashval)
 690                         low = mid + 1;
 691                 else
 692                         high = mid - 1;
 693                 if (low > high) {
 694                         ASSERT(args->oknoent);
 695                         xfs_da_brelse(tp, bp);
 696                         return XFS_ERROR(ENOENT);
 697                 }
 698         }
 699         /*
 700          * Back up to the first one with the right hash value.
 701          */
 702         while (mid > 0 && be32_to_cpu(blp[mid - 1].hashval) == args->hashval) {
 703                 mid--;
 704         }
 705         /*
 706          * Now loop forward through all the entries with the
 707          * right hash value looking for our name.
 708          */
 709         do {
 710                 if ((addr = be32_to_cpu(blp[mid].address)) == XFS_DIR2_NULL_DATAPTR)
 711                         continue;
 712                 /*
 713                  * Get pointer to the entry from the leaf.
 714                  */
 715                 dep = (xfs_dir2_data_entry_t *)
 716                         ((char *)block + xfs_dir2_dataptr_to_off(mp, addr));
 717                 /*
 718                  * Compare, if it's right give back buffer & entry number.
 719                  */
 720                 if (dep->namelen == args->namelen &&
 721                     dep->name[0] == args->name[0] &&
 722                     memcmp(dep->name, args->name, args->namelen) == 0) {
 723                         *bpp = bp;
 724                         *entno = mid;
 725                         return 0;
 726                 }
 727         } while (++mid < be32_to_cpu(btp->count) && be32_to_cpu(blp[mid].hashval) == hash);
 728         /*
 729          * No match, release the buffer and return ENOENT.
 730          */
 731         ASSERT(args->oknoent);
 732         xfs_da_brelse(tp, bp);
 733         return XFS_ERROR(ENOENT);
 734 }
 735
 736 /*
 737  * Remove an entry from a block format directory.
 738  * If that makes the block small enough to fit in shortform, transform it.
 739  */
 740 int                                             /* error */
 741 xfs_dir2_block_removename(
 742         xfs_da_args_t           *args)          /* directory operation args */
 743 {
 744         xfs_dir2_block_t        *block;         /* block structure */
 745         xfs_dir2_leaf_entry_t   *blp;           /* block leaf pointer */
 746         xfs_dabuf_t             *bp;            /* block buffer */
 747         xfs_dir2_block_tail_t   *btp;           /* block tail */
 748         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 749         xfs_inode_t             *dp;            /* incore inode */
 750         int                     ent;            /* block leaf entry index */
 751         int                     error;          /* error return value */
 752         xfs_mount_t             *mp;            /* filesystem mount point */
 753         int                     needlog;        /* need to log block header */
 754         int                     needscan;       /* need to fixup bestfree */
 755         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 756         int                     size;           /* shortform size */
 757         xfs_trans_t             *tp;            /* transaction pointer */
 758
 759         xfs_dir2_trace_args("block_removename", args);
 760         /*
 761          * Look up the entry in the block.  Gets the buffer and entry index.
 762          * It will always be there, the vnodeops level does a lookup first.
 763          */
 764         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 765                 return error;
 766         }
 767         dp = args->dp;
 768         tp = args->trans;
 769         mp = dp->i_mount;
 770         block = bp->data;
 771         btp = xfs_dir2_block_tail_p(mp, block);
 772         blp = xfs_dir2_block_leaf_p(btp);
 773         /*
 774          * Point to the data entry using the leaf entry.
 775          */
 776         dep = (xfs_dir2_data_entry_t *)
 777               ((char *)block + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 778         /*
 779          * Mark the data entry's space free.
 780          */
 781         needlog = needscan = 0;
 782         xfs_dir2_data_make_free(tp, bp,
 783                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)block),
 784                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
 785         /*
 786          * Fix up the block tail.
 787          */
 788         be32_add(&btp->stale, 1);
 789         xfs_dir2_block_log_tail(tp, bp);
 790         /*
 791          * Remove the leaf entry by marking it stale.
 792          */
 793         blp[ent].address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 794         xfs_dir2_block_log_leaf(tp, bp, ent, ent);
 795         /*
 796          * Fix up bestfree, log the header if necessary.
 797          */
 798         if (needscan)
 799                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
 800         if (needlog)
 801                 xfs_dir2_data_log_header(tp, bp);
 802         xfs_dir2_data_check(dp, bp);
 803         /*
 804          * See if the size as a shortform is good enough.
 805          */
 806         if ((size = xfs_dir2_block_sfsize(dp, block, &sfh)) >
 807             XFS_IFORK_DSIZE(dp)) {
 808                 xfs_da_buf_done(bp);
 809                 return 0;
 810         }
 811         /*
 812          * If it works, do the conversion.
 813          */
 814         return xfs_dir2_block_to_sf(args, bp, size, &sfh);
 815 }
 816
 817 /*
 818  * Replace an entry in a V2 block directory.
 819  * Change the inode number to the new value.
 820  */
 821 int                                             /* error */
 822 xfs_dir2_block_replace(
 823         xfs_da_args_t           *args)          /* directory operation args */
 824 {
 825         xfs_dir2_block_t        *block;         /* block structure */
 826         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 827         xfs_dabuf_t             *bp;            /* block buffer */
 828         xfs_dir2_block_tail_t   *btp;           /* block tail */
 829         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 830         xfs_inode_t             *dp;            /* incore inode */
 831         int                     ent;            /* leaf entry index */
 832         int                     error;          /* error return value */
 833         xfs_mount_t             *mp;            /* filesystem mount point */
 834
 835         xfs_dir2_trace_args("block_replace", args);
 836         /*
 837          * Lookup the entry in the directory.  Get buffer and entry index.
 838          * This will always succeed since the caller has already done a lookup.
 839          */
 840         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 841                 return error;
 842         }
 843         dp = args->dp;
 844         mp = dp->i_mount;
 845         block = bp->data;
 846         btp = xfs_dir2_block_tail_p(mp, block);
 847         blp = xfs_dir2_block_leaf_p(btp);
 848         /*
 849          * Point to the data entry we need to change.
 850          */
 851         dep = (xfs_dir2_data_entry_t *)
 852               ((char *)block + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 853         ASSERT(be64_to_cpu(dep->inumber) != args->inumber);
 854         /*
 855          * Change the inode number to the new value.
 856          */
 857         dep->inumber = cpu_to_be64(args->inumber);
 858         xfs_dir2_data_log_entry(args->trans, bp, dep);
 859         xfs_dir2_data_check(dp, bp);
 860         xfs_da_buf_done(bp);
 861         return 0;
 862 }
 863
 864 /*
 865  * Qsort comparison routine for the block leaf entries.
 866  */
 867 static int                                      /* sort order */
 868 xfs_dir2_block_sort(
 869         const void                      *a,     /* first leaf entry */
 870         const void                      *b)     /* second leaf entry */
 871 {
 872         const xfs_dir2_leaf_entry_t     *la;    /* first leaf entry */
 873         const xfs_dir2_leaf_entry_t     *lb;    /* second leaf entry */
 874
 875         la = a;
 876         lb = b;
 877         return be32_to_cpu(la->hashval) < be32_to_cpu(lb->hashval) ? -1 :
 878                 (be32_to_cpu(la->hashval) > be32_to_cpu(lb->hashval) ? 1 : 0);
 879 }
 880
 881 /*
 882  * Convert a V2 leaf directory to a V2 block directory if possible.
 883  */
 884 int                                             /* error */
 885 xfs_dir2_leaf_to_block(
 886         xfs_da_args_t           *args,          /* operation arguments */
 887         xfs_dabuf_t             *lbp,           /* leaf buffer */
 888         xfs_dabuf_t             *dbp)           /* data buffer */
 889 {
 890         __be16                  *bestsp;        /* leaf bests table */
 891         xfs_dir2_block_t        *block;         /* block structure */
 892         xfs_dir2_block_tail_t   *btp;           /* block tail */
 893         xfs_inode_t             *dp;            /* incore directory inode */
 894         xfs_dir2_data_unused_t  *dup;           /* unused data entry */
 895         int                     error;          /* error return value */
 896         int                     from;           /* leaf from index */
 897         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 898         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 899         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 900         xfs_mount_t             *mp;            /* file system mount point */
 901         int                     needlog;        /* need to log data header */
 902         int                     needscan;       /* need to scan for bestfree */
 903         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 904         int                     size;           /* bytes used */
 905         __be16                  *tagp;          /* end of entry (tag) */
 906         int                     to;             /* block/leaf to index */
 907         xfs_trans_t             *tp;            /* transaction pointer */
 908
 909         xfs_dir2_trace_args_bb("leaf_to_block", args, lbp, dbp);
 910         dp = args->dp;
 911         tp = args->trans;
 912         mp = dp->i_mount;
 913         leaf = lbp->data;
 914         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
 915         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 916         /*
 917          * If there are data blocks other than the first one, take this
 918          * opportunity to remove trailing empty data blocks that may have
 919          * been left behind during no-space-reservation operations.
 920          * These will show up in the leaf bests table.
 921          */
 922         while (dp->i_d.di_size > mp->m_dirblksize) {
 923                 bestsp = xfs_dir2_leaf_bests_p(ltp);
 924                 if (be16_to_cpu(bestsp[be32_to_cpu(ltp->bestcount) - 1]) ==
 925                     mp->m_dirblksize - (uint)sizeof(block->hdr)) {
 926                         if ((error =
 927                             xfs_dir2_leaf_trim_data(args, lbp,
 928                                     (xfs_dir2_db_t)(be32_to_cpu(ltp->bestcount) - 1))))
 929                                 goto out;
 930                 } else {
 931                         error = 0;
 932                         goto out;
 933                 }
 934         }
 935         /*
 936          * Read the data block if we don't already have it, give up if it fails.
 937          */
 938         if (dbp == NULL &&
 939             (error = xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &dbp,
 940                     XFS_DATA_FORK))) {
 941                 goto out;
 942         }
 943         block = dbp->data;
 944         ASSERT(be32_to_cpu(block->hdr.magic) == XFS_DIR2_DATA_MAGIC);
 945         /*
 946          * Size of the "leaf" area in the block.
 947          */
 948         size = (uint)sizeof(block->tail) +
 949                (uint)sizeof(*lep) * (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale));
 950         /*
 951          * Look at the last data entry.
 952          */
 953         tagp = (__be16 *)((char *)block + mp->m_dirblksize) - 1;
 954         dup = (xfs_dir2_data_unused_t *)((char *)block + be16_to_cpu(*tagp));
 955         /*
 956          * If it's not free or is too short we can't do it.
 957          */
 958         if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG ||
 959             be16_to_cpu(dup->length) < size) {
 960                 error = 0;
 961                 goto out;
 962         }
 963         /*
 964          * Start converting it to block form.
 965          */
 966         block->hdr.magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
 967         needlog = 1;
 968         needscan = 0;
 969         /*
 970          * Use up the space at the end of the block (blp/btp).
 971          */
 972         xfs_dir2_data_use_free(tp, dbp, dup, mp->m_dirblksize - size, size,
 973                 &needlog, &needscan);
 974         /*
 975          * Initialize the block tail.
 976          */
 977         btp = xfs_dir2_block_tail_p(mp, block);
 978         btp->count = cpu_to_be32(be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale));
 979         btp->stale = 0;
 980         xfs_dir2_block_log_tail(tp, dbp);
 981         /*
 982          * Initialize the block leaf area.  We compact out stale entries.
 983          */
 984         lep = xfs_dir2_block_leaf_p(btp);
 985         for (from = to = 0; from < be16_to_cpu(leaf->hdr.count); from++) {
 986                 if (be32_to_cpu(leaf->ents[from].address) == XFS_DIR2_NULL_DATAPTR)
 987                         continue;
 988                 lep[to++] = leaf->ents[from];
 989         }
 990         ASSERT(to == be32_to_cpu(btp->count));
 991         xfs_dir2_block_log_leaf(tp, dbp, 0, be32_to_cpu(btp->count) - 1);
 992         /*
 993          * Scan the bestfree if we need it and log the data block header.
 994          */
 995         if (needscan)
 996                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
 997         if (needlog)
 998                 xfs_dir2_data_log_header(tp, dbp);
 999         /*
1000          * Pitch the old leaf block.
1001          */
1002         error = xfs_da_shrink_inode(args, mp->m_dirleafblk, lbp);
1003         lbp = NULL;
1004         if (error) {
1005                 goto out;
1006         }
1007         /*
1008          * Now see if the resulting block can be shrunken to shortform.
1009          */
1010         if ((size = xfs_dir2_block_sfsize(dp, block, &sfh)) >
1011             XFS_IFORK_DSIZE(dp)) {
1012                 error = 0;
1013                 goto out;
1014         }
1015         return xfs_dir2_block_to_sf(args, dbp, size, &sfh);
1016 out:
1017         if (lbp)
1018                 xfs_da_buf_done(lbp);
1019         if (dbp)
1020                 xfs_da_buf_done(dbp);
1021         return error;
1022 }
1023
1024 /*
1025  * Convert the shortform directory to block form.
1026  */
1027 int                                             /* error */
1028 xfs_dir2_sf_to_block(
1029         xfs_da_args_t           *args)          /* operation arguments */
1030 {
1031         xfs_dir2_db_t           blkno;          /* dir-relative block # (0) */
1032         xfs_dir2_block_t        *block;         /* block structure */
1033         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
1034         xfs_dabuf_t             *bp;            /* block buffer */
1035         xfs_dir2_block_tail_t   *btp;           /* block tail pointer */
1036         char                    *buf;           /* sf buffer */
1037         int                     buf_len;
1038         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1039         xfs_inode_t             *dp;            /* incore directory inode */
1040         int                     dummy;          /* trash */
1041         xfs_dir2_data_unused_t  *dup;           /* unused entry pointer */
1042         int                     endoffset;      /* end of data objects */
1043         int                     error;          /* error return value */
1044         int                     i;              /* index */
1045         xfs_mount_t             *mp;            /* filesystem mount point */
1046         int                     needlog;        /* need to log block header */
1047         int                     needscan;       /* need to scan block freespc */
1048         int                     newoffset;      /* offset from current entry */
1049         int                     offset;         /* target block offset */
1050         xfs_dir2_sf_entry_t     *sfep;          /* sf entry pointer */
1051         xfs_dir2_sf_t           *sfp;           /* shortform structure */
1052         __be16                  *tagp;          /* end of data entry */
1053         xfs_trans_t             *tp;            /* transaction pointer */
1054
1055         xfs_dir2_trace_args("sf_to_block", args);
1056         dp = args->dp;
1057         tp = args->trans;
1058         mp = dp->i_mount;
1059         ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
1060         /*
1061          * Bomb out if the shortform directory is way too short.
1062          */
1063         if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
1064                 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1065                 return XFS_ERROR(EIO);
1066         }
1067         ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
1068         ASSERT(dp->i_df.if_u1.if_data != NULL);
1069         sfp = (xfs_dir2_sf_t *)dp->i_df.if_u1.if_data;
1070         ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->hdr.i8count));
1071         /*
1072          * Copy the directory into the stack buffer.
1073          * Then pitch the incore inode data so we can make extents.
1074          */
1075
1076         buf_len = dp->i_df.if_bytes;
1077         buf = kmem_alloc(dp->i_df.if_bytes, KM_SLEEP);
1078
1079         memcpy(buf, sfp, dp->i_df.if_bytes);
1080         xfs_idata_realloc(dp, -dp->i_df.if_bytes, XFS_DATA_FORK);
1081         dp->i_d.di_size = 0;
1082         xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1083         /*
1084          * Reset pointer - old sfp is gone.
1085          */
1086         sfp = (xfs_dir2_sf_t *)buf;
1087         /*
1088          * Add block 0 to the inode.
1089          */
1090         error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE, &blkno);
1091         if (error) {
1092                 kmem_free(buf, buf_len);
1093                 return error;
1094         }
1095         /*
1096          * Initialize the data block.
1097          */
1098         error = xfs_dir2_data_init(args, blkno, &bp);
1099         if (error) {
1100                 kmem_free(buf, buf_len);
1101                 return error;
1102         }
1103         block = bp->data;
1104         block->hdr.magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
1105         /*
1106          * Compute size of block "tail" area.
1107          */
1108         i = (uint)sizeof(*btp) +
1109             (sfp->hdr.count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t);
1110         /*
1111          * The whole thing is initialized to free by the init routine.
1112          * Say we're using the leaf and tail area.
1113          */
1114         dup = (xfs_dir2_data_unused_t *)block->u;
1115         needlog = needscan = 0;
1116         xfs_dir2_data_use_free(tp, bp, dup, mp->m_dirblksize - i, i, &needlog,
1117                 &needscan);
1118         ASSERT(needscan == 0);
1119         /*
1120          * Fill in the tail.
1121          */
1122         btp = xfs_dir2_block_tail_p(mp, block);
1123         btp->count = cpu_to_be32(sfp->hdr.count + 2);   /* ., .. */
1124         btp->stale = 0;
1125         blp = xfs_dir2_block_leaf_p(btp);
1126         endoffset = (uint)((char *)blp - (char *)block);
1127         /*
1128          * Remove the freespace, we'll manage it.
1129          */
1130         xfs_dir2_data_use_free(tp, bp, dup,
1131                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)block),
1132                 be16_to_cpu(dup->length), &needlog, &needscan);
1133         /*
1134          * Create entry for .
1135          */
1136         dep = (xfs_dir2_data_entry_t *)
1137               ((char *)block + XFS_DIR2_DATA_DOT_OFFSET);
1138         dep->inumber = cpu_to_be64(dp->i_ino);
1139         dep->namelen = 1;
1140         dep->name[0] = '.';
1141         tagp = xfs_dir2_data_entry_tag_p(dep);
1142         *tagp = cpu_to_be16((char *)dep - (char *)block);
1143         xfs_dir2_data_log_entry(tp, bp, dep);
1144         blp[0].hashval = cpu_to_be32(xfs_dir_hash_dot);
1145         blp[0].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1146                                 (char *)dep - (char *)block));
1147         /*
1148          * Create entry for ..
1149          */
1150         dep = (xfs_dir2_data_entry_t *)
1151                 ((char *)block + XFS_DIR2_DATA_DOTDOT_OFFSET);
1152         dep->inumber = cpu_to_be64(xfs_dir2_sf_get_inumber(sfp, &sfp->hdr.parent));
1153         dep->namelen = 2;
1154         dep->name[0] = dep->name[1] = '.';
1155         tagp = xfs_dir2_data_entry_tag_p(dep);
1156         *tagp = cpu_to_be16((char *)dep - (char *)block);
1157         xfs_dir2_data_log_entry(tp, bp, dep);
1158         blp[1].hashval = cpu_to_be32(xfs_dir_hash_dotdot);
1159         blp[1].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1160                                 (char *)dep - (char *)block));
1161         offset = XFS_DIR2_DATA_FIRST_OFFSET;
1162         /*
1163          * Loop over existing entries, stuff them in.
1164          */
1165         if ((i = 0) == sfp->hdr.count)
1166                 sfep = NULL;
1167         else
1168                 sfep = xfs_dir2_sf_firstentry(sfp);
1169         /*
1170          * Need to preserve the existing offset values in the sf directory.
1171          * Insert holes (unused entries) where necessary.
1172          */
1173         while (offset < endoffset) {
1174                 /*
1175                  * sfep is null when we reach the end of the list.
1176                  */
1177                 if (sfep == NULL)
1178                         newoffset = endoffset;
1179                 else
1180                         newoffset = xfs_dir2_sf_get_offset(sfep);
1181                 /*
1182                  * There should be a hole here, make one.
1183                  */
1184                 if (offset < newoffset) {
1185                         dup = (xfs_dir2_data_unused_t *)
1186                               ((char *)block + offset);
1187                         dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1188                         dup->length = cpu_to_be16(newoffset - offset);
1189                         *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16(
1190                                 ((char *)dup - (char *)block));
1191                         xfs_dir2_data_log_unused(tp, bp, dup);
1192                         (void)xfs_dir2_data_freeinsert((xfs_dir2_data_t *)block,
1193                                 dup, &dummy);
1194                         offset += be16_to_cpu(dup->length);
1195                         continue;
1196                 }
1197                 /*
1198                  * Copy a real entry.
1199                  */
1200                 dep = (xfs_dir2_data_entry_t *)((char *)block + newoffset);
1201                 dep->inumber = cpu_to_be64(xfs_dir2_sf_get_inumber(sfp,
1202                                 xfs_dir2_sf_inumberp(sfep)));
1203                 dep->namelen = sfep->namelen;
1204                 memcpy(dep->name, sfep->name, dep->namelen);
1205                 tagp = xfs_dir2_data_entry_tag_p(dep);
1206                 *tagp = cpu_to_be16((char *)dep - (char *)block);
1207                 xfs_dir2_data_log_entry(tp, bp, dep);
1208                 blp[2 + i].hashval = cpu_to_be32(xfs_da_hashname(
1209                                         (char *)sfep->name, sfep->namelen));
1210                 blp[2 + i].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1211                                                  (char *)dep - (char *)block));
1212                 offset = (int)((char *)(tagp + 1) - (char *)block);
1213                 if (++i == sfp->hdr.count)
1214                         sfep = NULL;
1215                 else
1216                         sfep = xfs_dir2_sf_nextentry(sfp, sfep);
1217         }
1218         /* Done with the temporary buffer */
1219         kmem_free(buf, buf_len);
1220         /*
1221          * Sort the leaf entries by hash value.
1222          */
1223         xfs_sort(blp, be32_to_cpu(btp->count), sizeof(*blp), xfs_dir2_block_sort);
1224         /*
1225          * Log the leaf entry area and tail.
1226          * Already logged the header in data_init, ignore needlog.
1227          */
1228         ASSERT(needscan == 0);
1229         xfs_dir2_block_log_leaf(tp, bp, 0, be32_to_cpu(btp->count) - 1);
1230         xfs_dir2_block_log_tail(tp, bp);
1231         xfs_dir2_data_check(dp, bp);
1232         xfs_da_buf_done(bp);
1233         return 0;
1234 }