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_trans.h"
  23 #include "xfs_sb.h"
  24 #include "xfs_ag.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_da_btree.h"
  27 #include "xfs_bmap_btree.h"
  28 #include "xfs_dinode.h"
  29 #include "xfs_inode.h"
  30 #include "xfs_inode_item.h"
  31 #include "xfs_dir2.h"
  32 #include "xfs_dir2_format.h"
  33 #include "xfs_dir2_priv.h"
  34 #include "xfs_error.h"
  35 #include "xfs_trace.h"
  36
  37 /*
  38  * Local function prototypes.
  39  */
  40 static void xfs_dir2_block_log_leaf(xfs_trans_t *tp, struct xfs_buf *bp,
  41                                     int first, int last);
  42 static void xfs_dir2_block_log_tail(xfs_trans_t *tp, struct xfs_buf *bp);
  43 static int xfs_dir2_block_lookup_int(xfs_da_args_t *args, struct xfs_buf **bpp,
  44                                      int *entno);
  45 static int xfs_dir2_block_sort(const void *a, const void *b);
  46
  47 static xfs_dahash_t xfs_dir_hash_dot, xfs_dir_hash_dotdot;
  48
  49 /*
  50  * One-time startup routine called from xfs_init().
  51  */
  52 void
  53 xfs_dir_startup(void)
  54 {
  55         xfs_dir_hash_dot = xfs_da_hashname((unsigned char *)".", 1);
  56         xfs_dir_hash_dotdot = xfs_da_hashname((unsigned char *)"..", 2);
  57 }
  58
  59 static void
  60 xfs_dir2_block_verify(
  61         struct xfs_buf          *bp)
  62 {
  63         struct xfs_mount        *mp = bp->b_target->bt_mount;
  64         struct xfs_dir2_data_hdr *hdr = bp->b_addr;
  65         int                     block_ok = 0;
  66
  67         block_ok = hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
  68         block_ok = block_ok && __xfs_dir2_data_check(NULL, bp) == 0;
  69
  70         if (!block_ok) {
  71                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, hdr);
  72                 xfs_buf_ioerror(bp, EFSCORRUPTED);
  73         }
  74
  75         bp->b_iodone = NULL;
  76         xfs_buf_ioend(bp, 0);
  77 }
  78
  79 static int
  80 xfs_dir2_block_read(
  81         struct xfs_trans        *tp,
  82         struct xfs_inode        *dp,
  83         struct xfs_buf          **bpp)
  84 {
  85         struct xfs_mount        *mp = dp->i_mount;
  86
  87         return xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, bpp,
  88                                         XFS_DATA_FORK, xfs_dir2_block_verify);
  89 }
  90
  91 static void
  92 xfs_dir2_block_need_space(
  93         struct xfs_dir2_data_hdr        *hdr,
  94         struct xfs_dir2_block_tail      *btp,
  95         struct xfs_dir2_leaf_entry      *blp,
  96         __be16                          **tagpp,
  97         struct xfs_dir2_data_unused     **dupp,
  98         struct xfs_dir2_data_unused     **enddupp,
  99         int                             *compact,
 100         int                             len)
 101 {
 102         struct xfs_dir2_data_free       *bf;
 103         __be16                          *tagp = NULL;
 104         struct xfs_dir2_data_unused     *dup = NULL;
 105         struct xfs_dir2_data_unused     *enddup = NULL;
 106
 107         *compact = 0;
 108         bf = hdr->bestfree;
 109
 110         /*
 111          * If there are stale entries we'll use one for the leaf.
 112          */
 113         if (btp->stale) {
 114                 if (be16_to_cpu(bf[0].length) >= len) {
 115                         /*
 116                          * The biggest entry enough to avoid compaction.
 117                          */
 118                         dup = (xfs_dir2_data_unused_t *)
 119                               ((char *)hdr + be16_to_cpu(bf[0].offset));
 120                         goto out;
 121                 }
 122
 123                 /*
 124                  * Will need to compact to make this work.
 125                  * Tag just before the first leaf entry.
 126                  */
 127                 *compact = 1;
 128                 tagp = (__be16 *)blp - 1;
 129
 130                 /* Data object just before the first leaf entry.  */
 131                 dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 132
 133                 /*
 134                  * If it's not free then the data will go where the
 135                  * leaf data starts now, if it works at all.
 136                  */
 137                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 138                         if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
 139                             (uint)sizeof(*blp) < len)
 140                                 dup = NULL;
 141                 } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
 142                         dup = NULL;
 143                 else
 144                         dup = (xfs_dir2_data_unused_t *)blp;
 145                 goto out;
 146         }
 147
 148         /*
 149          * no stale entries, so just use free space.
 150          * Tag just before the first leaf entry.
 151          */
 152         tagp = (__be16 *)blp - 1;
 153
 154         /* Data object just before the first leaf entry.  */
 155         enddup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 156
 157         /*
 158          * If it's not free then can't do this add without cleaning up:
 159          * the space before the first leaf entry needs to be free so it
 160          * can be expanded to hold the pointer to the new entry.
 161          */
 162         if (be16_to_cpu(enddup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 163                 /*
 164                  * Check out the biggest freespace and see if it's the same one.
 165                  */
 166                 dup = (xfs_dir2_data_unused_t *)
 167                       ((char *)hdr + be16_to_cpu(bf[0].offset));
 168                 if (dup != enddup) {
 169                         /*
 170                          * Not the same free entry, just check its length.
 171                          */
 172                         if (be16_to_cpu(dup->length) < len)
 173                                 dup = NULL;
 174                         goto out;
 175                 }
 176
 177                 /*
 178                  * It is the biggest freespace, can it hold the leaf too?
 179                  */
 180                 if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
 181                         /*
 182                          * Yes, use the second-largest entry instead if it works.
 183                          */
 184                         if (be16_to_cpu(bf[1].length) >= len)
 185                                 dup = (xfs_dir2_data_unused_t *)
 186                                       ((char *)hdr + be16_to_cpu(bf[1].offset));
 187                         else
 188                                 dup = NULL;
 189                 }
 190         }
 191 out:
 192         *tagpp = tagp;
 193         *dupp = dup;
 194         *enddupp = enddup;
 195 }
 196
 197 /*
 198  * compact the leaf entries.
 199  * Leave the highest-numbered stale entry stale.
 200  * XXX should be the one closest to mid but mid is not yet computed.
 201  */
 202 static void
 203 xfs_dir2_block_compact(
 204         struct xfs_trans                *tp,
 205         struct xfs_buf                  *bp,
 206         struct xfs_dir2_data_hdr        *hdr,
 207         struct xfs_dir2_block_tail      *btp,
 208         struct xfs_dir2_leaf_entry      *blp,
 209         int                             *needlog,
 210         int                             *lfloghigh,
 211         int                             *lfloglow)
 212 {
 213         int                     fromidx;        /* source leaf index */
 214         int                     toidx;          /* target leaf index */
 215         int                     needscan = 0;
 216         int                     highstale;      /* high stale index */
 217
 218         fromidx = toidx = be32_to_cpu(btp->count) - 1;
 219         highstale = *lfloghigh = -1;
 220         for (; fromidx >= 0; fromidx--) {
 221                 if (blp[fromidx].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
 222                         if (highstale == -1)
 223                                 highstale = toidx;
 224                         else {
 225                                 if (*lfloghigh == -1)
 226                                         *lfloghigh = toidx;
 227                                 continue;
 228                         }
 229                 }
 230                 if (fromidx < toidx)
 231                         blp[toidx] = blp[fromidx];
 232                 toidx--;
 233         }
 234         *lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
 235         *lfloghigh -= be32_to_cpu(btp->stale) - 1;
 236         be32_add_cpu(&btp->count, -(be32_to_cpu(btp->stale) - 1));
 237         xfs_dir2_data_make_free(tp, bp,
 238                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 239                 (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
 240                 needlog, &needscan);
 241         blp += be32_to_cpu(btp->stale) - 1;
 242         btp->stale = cpu_to_be32(1);
 243         /*
 244          * If we now need to rebuild the bestfree map, do so.
 245          * This needs to happen before the next call to use_free.
 246          */
 247         if (needscan)
 248                 xfs_dir2_data_freescan(tp->t_mountp, hdr, needlog);
 249 }
 250
 251 /*
 252  * Add an entry to a block directory.
 253  */
 254 int                                             /* error */
 255 xfs_dir2_block_addname(
 256         xfs_da_args_t           *args)          /* directory op arguments */
 257 {
 258         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 259         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 260         struct xfs_buf          *bp;            /* buffer for block */
 261         xfs_dir2_block_tail_t   *btp;           /* block tail */
 262         int                     compact;        /* need to compact leaf ents */
 263         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 264         xfs_inode_t             *dp;            /* directory inode */
 265         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 266         int                     error;          /* error return value */
 267         xfs_dir2_data_unused_t  *enddup=NULL;   /* unused at end of data */
 268         xfs_dahash_t            hash;           /* hash value of found entry */
 269         int                     high;           /* high index for binary srch */
 270         int                     highstale;      /* high stale index */
 271         int                     lfloghigh=0;    /* last final leaf to log */
 272         int                     lfloglow=0;     /* first final leaf to log */
 273         int                     len;            /* length of the new entry */
 274         int                     low;            /* low index for binary srch */
 275         int                     lowstale;       /* low stale index */
 276         int                     mid=0;          /* midpoint for binary srch */
 277         xfs_mount_t             *mp;            /* filesystem mount point */
 278         int                     needlog;        /* need to log header */
 279         int                     needscan;       /* need to rescan freespace */
 280         __be16                  *tagp;          /* pointer to tag value */
 281         xfs_trans_t             *tp;            /* transaction structure */
 282
 283         trace_xfs_dir2_block_addname(args);
 284
 285         dp = args->dp;
 286         tp = args->trans;
 287         mp = dp->i_mount;
 288
 289         /* Read the (one and only) directory block into bp. */
 290         error = xfs_dir2_block_read(tp, dp, &bp);
 291         if (error)
 292                 return error;
 293
 294         len = xfs_dir2_data_entsize(args->namelen);
 295
 296         /*
 297          * Set up pointers to parts of the block.
 298          */
 299         hdr = bp->b_addr;
 300         btp = xfs_dir2_block_tail_p(mp, hdr);
 301         blp = xfs_dir2_block_leaf_p(btp);
 302
 303         /*
 304          * Find out if we can reuse stale entries or whether we need extra
 305          * space for entry and new leaf.
 306          */
 307         xfs_dir2_block_need_space(hdr, btp, blp, &tagp, &dup,
 308                                   &enddup, &compact, len);
 309
 310         /*
 311          * Done everything we need for a space check now.
 312          */
 313         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 314                 xfs_trans_brelse(tp, bp);
 315                 if (!dup)
 316                         return XFS_ERROR(ENOSPC);
 317                 return 0;
 318         }
 319
 320         /*
 321          * If we don't have space for the new entry & leaf ...
 322          */
 323         if (!dup) {
 324                 /* Don't have a space reservation: return no-space.  */
 325                 if (args->total == 0)
 326                         return XFS_ERROR(ENOSPC);
 327                 /*
 328                  * Convert to the next larger format.
 329                  * Then add the new entry in that format.
 330                  */
 331                 error = xfs_dir2_block_to_leaf(args, bp);
 332                 if (error)
 333                         return error;
 334                 return xfs_dir2_leaf_addname(args);
 335         }
 336
 337         needlog = needscan = 0;
 338
 339         /*
 340          * If need to compact the leaf entries, do it now.
 341          */
 342         if (compact)
 343                 xfs_dir2_block_compact(tp, bp, hdr, btp, blp, &needlog,
 344                                       &lfloghigh, &lfloglow);
 345         else if (btp->stale) {
 346                 /*
 347                  * Set leaf logging boundaries to impossible state.
 348                  * For the no-stale case they're set explicitly.
 349                  */
 350                 lfloglow = be32_to_cpu(btp->count);
 351                 lfloghigh = -1;
 352         }
 353
 354         /*
 355          * Find the slot that's first lower than our hash value, -1 if none.
 356          */
 357         for (low = 0, high = be32_to_cpu(btp->count) - 1; low <= high; ) {
 358                 mid = (low + high) >> 1;
 359                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 360                         break;
 361                 if (hash < args->hashval)
 362                         low = mid + 1;
 363                 else
 364                         high = mid - 1;
 365         }
 366         while (mid >= 0 && be32_to_cpu(blp[mid].hashval) >= args->hashval) {
 367                 mid--;
 368         }
 369         /*
 370          * No stale entries, will use enddup space to hold new leaf.
 371          */
 372         if (!btp->stale) {
 373                 /*
 374                  * Mark the space needed for the new leaf entry, now in use.
 375                  */
 376                 xfs_dir2_data_use_free(tp, bp, enddup,
 377                         (xfs_dir2_data_aoff_t)
 378                         ((char *)enddup - (char *)hdr + be16_to_cpu(enddup->length) -
 379                          sizeof(*blp)),
 380                         (xfs_dir2_data_aoff_t)sizeof(*blp),
 381                         &needlog, &needscan);
 382                 /*
 383                  * Update the tail (entry count).
 384                  */
 385                 be32_add_cpu(&btp->count, 1);
 386                 /*
 387                  * If we now need to rebuild the bestfree map, do so.
 388                  * This needs to happen before the next call to use_free.
 389                  */
 390                 if (needscan) {
 391                         xfs_dir2_data_freescan(mp, hdr, &needlog);
 392                         needscan = 0;
 393                 }
 394                 /*
 395                  * Adjust pointer to the first leaf entry, we're about to move
 396                  * the table up one to open up space for the new leaf entry.
 397                  * Then adjust our index to match.
 398                  */
 399                 blp--;
 400                 mid++;
 401                 if (mid)
 402                         memmove(blp, &blp[1], mid * sizeof(*blp));
 403                 lfloglow = 0;
 404                 lfloghigh = mid;
 405         }
 406         /*
 407          * Use a stale leaf for our new entry.
 408          */
 409         else {
 410                 for (lowstale = mid;
 411                      lowstale >= 0 &&
 412                         blp[lowstale].address !=
 413                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 414                      lowstale--)
 415                         continue;
 416                 for (highstale = mid + 1;
 417                      highstale < be32_to_cpu(btp->count) &&
 418                         blp[highstale].address !=
 419                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR) &&
 420                         (lowstale < 0 || mid - lowstale > highstale - mid);
 421                      highstale++)
 422                         continue;
 423                 /*
 424                  * Move entries toward the low-numbered stale entry.
 425                  */
 426                 if (lowstale >= 0 &&
 427                     (highstale == be32_to_cpu(btp->count) ||
 428                      mid - lowstale <= highstale - mid)) {
 429                         if (mid - lowstale)
 430                                 memmove(&blp[lowstale], &blp[lowstale + 1],
 431                                         (mid - lowstale) * sizeof(*blp));
 432                         lfloglow = MIN(lowstale, lfloglow);
 433                         lfloghigh = MAX(mid, lfloghigh);
 434                 }
 435                 /*
 436                  * Move entries toward the high-numbered stale entry.
 437                  */
 438                 else {
 439                         ASSERT(highstale < be32_to_cpu(btp->count));
 440                         mid++;
 441                         if (highstale - mid)
 442                                 memmove(&blp[mid + 1], &blp[mid],
 443                                         (highstale - mid) * sizeof(*blp));
 444                         lfloglow = MIN(mid, lfloglow);
 445                         lfloghigh = MAX(highstale, lfloghigh);
 446                 }
 447                 be32_add_cpu(&btp->stale, -1);
 448         }
 449         /*
 450          * Point to the new data entry.
 451          */
 452         dep = (xfs_dir2_data_entry_t *)dup;
 453         /*
 454          * Fill in the leaf entry.
 455          */
 456         blp[mid].hashval = cpu_to_be32(args->hashval);
 457         blp[mid].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
 458                                 (char *)dep - (char *)hdr));
 459         xfs_dir2_block_log_leaf(tp, bp, lfloglow, lfloghigh);
 460         /*
 461          * Mark space for the data entry used.
 462          */
 463         xfs_dir2_data_use_free(tp, bp, dup,
 464                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
 465                 (xfs_dir2_data_aoff_t)len, &needlog, &needscan);
 466         /*
 467          * Create the new data entry.
 468          */
 469         dep->inumber = cpu_to_be64(args->inumber);
 470         dep->namelen = args->namelen;
 471         memcpy(dep->name, args->name, args->namelen);
 472         tagp = xfs_dir2_data_entry_tag_p(dep);
 473         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 474         /*
 475          * Clean up the bestfree array and log the header, tail, and entry.
 476          */
 477         if (needscan)
 478                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 479         if (needlog)
 480                 xfs_dir2_data_log_header(tp, bp);
 481         xfs_dir2_block_log_tail(tp, bp);
 482         xfs_dir2_data_log_entry(tp, bp, dep);
 483         xfs_dir2_data_check(dp, bp);
 484         return 0;
 485 }
 486
 487 /*
 488  * Readdir for block directories.
 489  */
 490 int                                             /* error */
 491 xfs_dir2_block_getdents(
 492         xfs_inode_t             *dp,            /* incore inode */
 493         void                    *dirent,
 494         xfs_off_t               *offset,
 495         filldir_t               filldir)
 496 {
 497         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 498         struct xfs_buf          *bp;            /* buffer for block */
 499         xfs_dir2_block_tail_t   *btp;           /* block tail */
 500         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 501         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 502         char                    *endptr;        /* end of the data entries */
 503         int                     error;          /* error return value */
 504         xfs_mount_t             *mp;            /* filesystem mount point */
 505         char                    *ptr;           /* current data entry */
 506         int                     wantoff;        /* starting block offset */
 507         xfs_off_t               cook;
 508
 509         mp = dp->i_mount;
 510         /*
 511          * If the block number in the offset is out of range, we're done.
 512          */
 513         if (xfs_dir2_dataptr_to_db(mp, *offset) > mp->m_dirdatablk)
 514                 return 0;
 515
 516         error = xfs_dir2_block_read(NULL, dp, &bp);
 517         if (error)
 518                 return error;
 519
 520         /*
 521          * Extract the byte offset we start at from the seek pointer.
 522          * We'll skip entries before this.
 523          */
 524         wantoff = xfs_dir2_dataptr_to_off(mp, *offset);
 525         hdr = bp->b_addr;
 526         xfs_dir2_data_check(dp, bp);
 527         /*
 528          * Set up values for the loop.
 529          */
 530         btp = xfs_dir2_block_tail_p(mp, hdr);
 531         ptr = (char *)(hdr + 1);
 532         endptr = (char *)xfs_dir2_block_leaf_p(btp);
 533
 534         /*
 535          * Loop over the data portion of the block.
 536          * Each object is a real entry (dep) or an unused one (dup).
 537          */
 538         while (ptr < endptr) {
 539                 dup = (xfs_dir2_data_unused_t *)ptr;
 540                 /*
 541                  * Unused, skip it.
 542                  */
 543                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 544                         ptr += be16_to_cpu(dup->length);
 545                         continue;
 546                 }
 547
 548                 dep = (xfs_dir2_data_entry_t *)ptr;
 549
 550                 /*
 551                  * Bump pointer for the next iteration.
 552                  */
 553                 ptr += xfs_dir2_data_entsize(dep->namelen);
 554                 /*
 555                  * The entry is before the desired starting point, skip it.
 556                  */
 557                 if ((char *)dep - (char *)hdr < wantoff)
 558                         continue;
 559
 560                 cook = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
 561                                             (char *)dep - (char *)hdr);
 562
 563                 /*
 564                  * If it didn't fit, set the final offset to here & return.
 565                  */
 566                 if (filldir(dirent, (char *)dep->name, dep->namelen,
 567                             cook & 0x7fffffff, be64_to_cpu(dep->inumber),
 568                             DT_UNKNOWN)) {
 569                         *offset = cook & 0x7fffffff;
 570                         xfs_trans_brelse(NULL, bp);
 571                         return 0;
 572                 }
 573         }
 574
 575         /*
 576          * Reached the end of the block.
 577          * Set the offset to a non-existent block 1 and return.
 578          */
 579         *offset = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk + 1, 0) &
 580                         0x7fffffff;
 581         xfs_trans_brelse(NULL, bp);
 582         return 0;
 583 }
 584
 585 /*
 586  * Log leaf entries from the block.
 587  */
 588 static void
 589 xfs_dir2_block_log_leaf(
 590         xfs_trans_t             *tp,            /* transaction structure */
 591         struct xfs_buf          *bp,            /* block buffer */
 592         int                     first,          /* index of first logged leaf */
 593         int                     last)           /* index of last logged leaf */
 594 {
 595         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 596         xfs_dir2_leaf_entry_t   *blp;
 597         xfs_dir2_block_tail_t   *btp;
 598
 599         btp = xfs_dir2_block_tail_p(tp->t_mountp, hdr);
 600         blp = xfs_dir2_block_leaf_p(btp);
 601         xfs_trans_log_buf(tp, bp, (uint)((char *)&blp[first] - (char *)hdr),
 602                 (uint)((char *)&blp[last + 1] - (char *)hdr - 1));
 603 }
 604
 605 /*
 606  * Log the block tail.
 607  */
 608 static void
 609 xfs_dir2_block_log_tail(
 610         xfs_trans_t             *tp,            /* transaction structure */
 611         struct xfs_buf          *bp)            /* block buffer */
 612 {
 613         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 614         xfs_dir2_block_tail_t   *btp;
 615
 616         btp = xfs_dir2_block_tail_p(tp->t_mountp, hdr);
 617         xfs_trans_log_buf(tp, bp, (uint)((char *)btp - (char *)hdr),
 618                 (uint)((char *)(btp + 1) - (char *)hdr - 1));
 619 }
 620
 621 /*
 622  * Look up an entry in the block.  This is the external routine,
 623  * xfs_dir2_block_lookup_int does the real work.
 624  */
 625 int                                             /* error */
 626 xfs_dir2_block_lookup(
 627         xfs_da_args_t           *args)          /* dir lookup arguments */
 628 {
 629         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 630         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 631         struct xfs_buf          *bp;            /* block buffer */
 632         xfs_dir2_block_tail_t   *btp;           /* block tail */
 633         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 634         xfs_inode_t             *dp;            /* incore inode */
 635         int                     ent;            /* entry index */
 636         int                     error;          /* error return value */
 637         xfs_mount_t             *mp;            /* filesystem mount point */
 638
 639         trace_xfs_dir2_block_lookup(args);
 640
 641         /*
 642          * Get the buffer, look up the entry.
 643          * If not found (ENOENT) then return, have no buffer.
 644          */
 645         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent)))
 646                 return error;
 647         dp = args->dp;
 648         mp = dp->i_mount;
 649         hdr = bp->b_addr;
 650         xfs_dir2_data_check(dp, bp);
 651         btp = xfs_dir2_block_tail_p(mp, hdr);
 652         blp = xfs_dir2_block_leaf_p(btp);
 653         /*
 654          * Get the offset from the leaf entry, to point to the data.
 655          */
 656         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
 657                 xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 658         /*
 659          * Fill in inode number, CI name if appropriate, release the block.
 660          */
 661         args->inumber = be64_to_cpu(dep->inumber);
 662         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
 663         xfs_trans_brelse(args->trans, bp);
 664         return XFS_ERROR(error);
 665 }
 666
 667 /*
 668  * Internal block lookup routine.
 669  */
 670 static int                                      /* error */
 671 xfs_dir2_block_lookup_int(
 672         xfs_da_args_t           *args,          /* dir lookup arguments */
 673         struct xfs_buf          **bpp,          /* returned block buffer */
 674         int                     *entno)         /* returned entry number */
 675 {
 676         xfs_dir2_dataptr_t      addr;           /* data entry address */
 677         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 678         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 679         struct xfs_buf          *bp;            /* block buffer */
 680         xfs_dir2_block_tail_t   *btp;           /* block tail */
 681         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 682         xfs_inode_t             *dp;            /* incore inode */
 683         int                     error;          /* error return value */
 684         xfs_dahash_t            hash;           /* found hash value */
 685         int                     high;           /* binary search high index */
 686         int                     low;            /* binary search low index */
 687         int                     mid;            /* binary search current idx */
 688         xfs_mount_t             *mp;            /* filesystem mount point */
 689         xfs_trans_t             *tp;            /* transaction pointer */
 690         enum xfs_dacmp          cmp;            /* comparison result */
 691
 692         dp = args->dp;
 693         tp = args->trans;
 694         mp = dp->i_mount;
 695
 696         error = xfs_dir2_block_read(tp, dp, &bp);
 697         if (error)
 698                 return error;
 699
 700         hdr = bp->b_addr;
 701         xfs_dir2_data_check(dp, bp);
 702         btp = xfs_dir2_block_tail_p(mp, hdr);
 703         blp = xfs_dir2_block_leaf_p(btp);
 704         /*
 705          * Loop doing a binary search for our hash value.
 706          * Find our entry, ENOENT if it's not there.
 707          */
 708         for (low = 0, high = be32_to_cpu(btp->count) - 1; ; ) {
 709                 ASSERT(low <= high);
 710                 mid = (low + high) >> 1;
 711                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 712                         break;
 713                 if (hash < args->hashval)
 714                         low = mid + 1;
 715                 else
 716                         high = mid - 1;
 717                 if (low > high) {
 718                         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 719                         xfs_trans_brelse(tp, bp);
 720                         return XFS_ERROR(ENOENT);
 721                 }
 722         }
 723         /*
 724          * Back up to the first one with the right hash value.
 725          */
 726         while (mid > 0 && be32_to_cpu(blp[mid - 1].hashval) == args->hashval) {
 727                 mid--;
 728         }
 729         /*
 730          * Now loop forward through all the entries with the
 731          * right hash value looking for our name.
 732          */
 733         do {
 734                 if ((addr = be32_to_cpu(blp[mid].address)) == XFS_DIR2_NULL_DATAPTR)
 735                         continue;
 736                 /*
 737                  * Get pointer to the entry from the leaf.
 738                  */
 739                 dep = (xfs_dir2_data_entry_t *)
 740                         ((char *)hdr + xfs_dir2_dataptr_to_off(mp, addr));
 741                 /*
 742                  * Compare name and if it's an exact match, return the index
 743                  * and buffer. If it's the first case-insensitive match, store
 744                  * the index and buffer and continue looking for an exact match.
 745                  */
 746                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 747                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 748                         args->cmpresult = cmp;
 749                         *bpp = bp;
 750                         *entno = mid;
 751                         if (cmp == XFS_CMP_EXACT)
 752                                 return 0;
 753                 }
 754         } while (++mid < be32_to_cpu(btp->count) &&
 755                         be32_to_cpu(blp[mid].hashval) == hash);
 756
 757         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 758         /*
 759          * Here, we can only be doing a lookup (not a rename or replace).
 760          * If a case-insensitive match was found earlier, return success.
 761          */
 762         if (args->cmpresult == XFS_CMP_CASE)
 763                 return 0;
 764         /*
 765          * No match, release the buffer and return ENOENT.
 766          */
 767         xfs_trans_brelse(tp, bp);
 768         return XFS_ERROR(ENOENT);
 769 }
 770
 771 /*
 772  * Remove an entry from a block format directory.
 773  * If that makes the block small enough to fit in shortform, transform it.
 774  */
 775 int                                             /* error */
 776 xfs_dir2_block_removename(
 777         xfs_da_args_t           *args)          /* directory operation args */
 778 {
 779         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 780         xfs_dir2_leaf_entry_t   *blp;           /* block leaf pointer */
 781         struct xfs_buf          *bp;            /* block buffer */
 782         xfs_dir2_block_tail_t   *btp;           /* block tail */
 783         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 784         xfs_inode_t             *dp;            /* incore inode */
 785         int                     ent;            /* block leaf entry index */
 786         int                     error;          /* error return value */
 787         xfs_mount_t             *mp;            /* filesystem mount point */
 788         int                     needlog;        /* need to log block header */
 789         int                     needscan;       /* need to fixup bestfree */
 790         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 791         int                     size;           /* shortform size */
 792         xfs_trans_t             *tp;            /* transaction pointer */
 793
 794         trace_xfs_dir2_block_removename(args);
 795
 796         /*
 797          * Look up the entry in the block.  Gets the buffer and entry index.
 798          * It will always be there, the vnodeops level does a lookup first.
 799          */
 800         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 801                 return error;
 802         }
 803         dp = args->dp;
 804         tp = args->trans;
 805         mp = dp->i_mount;
 806         hdr = bp->b_addr;
 807         btp = xfs_dir2_block_tail_p(mp, hdr);
 808         blp = xfs_dir2_block_leaf_p(btp);
 809         /*
 810          * Point to the data entry using the leaf entry.
 811          */
 812         dep = (xfs_dir2_data_entry_t *)
 813               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 814         /*
 815          * Mark the data entry's space free.
 816          */
 817         needlog = needscan = 0;
 818         xfs_dir2_data_make_free(tp, bp,
 819                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
 820                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
 821         /*
 822          * Fix up the block tail.
 823          */
 824         be32_add_cpu(&btp->stale, 1);
 825         xfs_dir2_block_log_tail(tp, bp);
 826         /*
 827          * Remove the leaf entry by marking it stale.
 828          */
 829         blp[ent].address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 830         xfs_dir2_block_log_leaf(tp, bp, ent, ent);
 831         /*
 832          * Fix up bestfree, log the header if necessary.
 833          */
 834         if (needscan)
 835                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 836         if (needlog)
 837                 xfs_dir2_data_log_header(tp, bp);
 838         xfs_dir2_data_check(dp, bp);
 839         /*
 840          * See if the size as a shortform is good enough.
 841          */
 842         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
 843         if (size > XFS_IFORK_DSIZE(dp))
 844                 return 0;
 845
 846         /*
 847          * If it works, do the conversion.
 848          */
 849         return xfs_dir2_block_to_sf(args, bp, size, &sfh);
 850 }
 851
 852 /*
 853  * Replace an entry in a V2 block directory.
 854  * Change the inode number to the new value.
 855  */
 856 int                                             /* error */
 857 xfs_dir2_block_replace(
 858         xfs_da_args_t           *args)          /* directory operation args */
 859 {
 860         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 861         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 862         struct xfs_buf          *bp;            /* block buffer */
 863         xfs_dir2_block_tail_t   *btp;           /* block tail */
 864         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 865         xfs_inode_t             *dp;            /* incore inode */
 866         int                     ent;            /* leaf entry index */
 867         int                     error;          /* error return value */
 868         xfs_mount_t             *mp;            /* filesystem mount point */
 869
 870         trace_xfs_dir2_block_replace(args);
 871
 872         /*
 873          * Lookup the entry in the directory.  Get buffer and entry index.
 874          * This will always succeed since the caller has already done a lookup.
 875          */
 876         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 877                 return error;
 878         }
 879         dp = args->dp;
 880         mp = dp->i_mount;
 881         hdr = bp->b_addr;
 882         btp = xfs_dir2_block_tail_p(mp, hdr);
 883         blp = xfs_dir2_block_leaf_p(btp);
 884         /*
 885          * Point to the data entry we need to change.
 886          */
 887         dep = (xfs_dir2_data_entry_t *)
 888               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 889         ASSERT(be64_to_cpu(dep->inumber) != args->inumber);
 890         /*
 891          * Change the inode number to the new value.
 892          */
 893         dep->inumber = cpu_to_be64(args->inumber);
 894         xfs_dir2_data_log_entry(args->trans, bp, dep);
 895         xfs_dir2_data_check(dp, bp);
 896         return 0;
 897 }
 898
 899 /*
 900  * Qsort comparison routine for the block leaf entries.
 901  */
 902 static int                                      /* sort order */
 903 xfs_dir2_block_sort(
 904         const void                      *a,     /* first leaf entry */
 905         const void                      *b)     /* second leaf entry */
 906 {
 907         const xfs_dir2_leaf_entry_t     *la;    /* first leaf entry */
 908         const xfs_dir2_leaf_entry_t     *lb;    /* second leaf entry */
 909
 910         la = a;
 911         lb = b;
 912         return be32_to_cpu(la->hashval) < be32_to_cpu(lb->hashval) ? -1 :
 913                 (be32_to_cpu(la->hashval) > be32_to_cpu(lb->hashval) ? 1 : 0);
 914 }
 915
 916 /*
 917  * Convert a V2 leaf directory to a V2 block directory if possible.
 918  */
 919 int                                             /* error */
 920 xfs_dir2_leaf_to_block(
 921         xfs_da_args_t           *args,          /* operation arguments */
 922         struct xfs_buf          *lbp,           /* leaf buffer */
 923         struct xfs_buf          *dbp)           /* data buffer */
 924 {
 925         __be16                  *bestsp;        /* leaf bests table */
 926         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 927         xfs_dir2_block_tail_t   *btp;           /* block tail */
 928         xfs_inode_t             *dp;            /* incore directory inode */
 929         xfs_dir2_data_unused_t  *dup;           /* unused data entry */
 930         int                     error;          /* error return value */
 931         int                     from;           /* leaf from index */
 932         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 933         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 934         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 935         xfs_mount_t             *mp;            /* file system mount point */
 936         int                     needlog;        /* need to log data header */
 937         int                     needscan;       /* need to scan for bestfree */
 938         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 939         int                     size;           /* bytes used */
 940         __be16                  *tagp;          /* end of entry (tag) */
 941         int                     to;             /* block/leaf to index */
 942         xfs_trans_t             *tp;            /* transaction pointer */
 943
 944         trace_xfs_dir2_leaf_to_block(args);
 945
 946         dp = args->dp;
 947         tp = args->trans;
 948         mp = dp->i_mount;
 949         leaf = lbp->b_addr;
 950         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
 951         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 952         /*
 953          * If there are data blocks other than the first one, take this
 954          * opportunity to remove trailing empty data blocks that may have
 955          * been left behind during no-space-reservation operations.
 956          * These will show up in the leaf bests table.
 957          */
 958         while (dp->i_d.di_size > mp->m_dirblksize) {
 959                 bestsp = xfs_dir2_leaf_bests_p(ltp);
 960                 if (be16_to_cpu(bestsp[be32_to_cpu(ltp->bestcount) - 1]) ==
 961                     mp->m_dirblksize - (uint)sizeof(*hdr)) {
 962                         if ((error =
 963                             xfs_dir2_leaf_trim_data(args, lbp,
 964                                     (xfs_dir2_db_t)(be32_to_cpu(ltp->bestcount) - 1))))
 965                                 return error;
 966                 } else
 967                         return 0;
 968         }
 969         /*
 970          * Read the data block if we don't already have it, give up if it fails.
 971          */
 972         if (!dbp) {
 973                 error = xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, &dbp,
 974                                         XFS_DATA_FORK, NULL);
 975                 if (error)
 976                         return error;
 977         }
 978         hdr = dbp->b_addr;
 979         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
 980         /*
 981          * Size of the "leaf" area in the block.
 982          */
 983         size = (uint)sizeof(xfs_dir2_block_tail_t) +
 984                (uint)sizeof(*lep) * (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale));
 985         /*
 986          * Look at the last data entry.
 987          */
 988         tagp = (__be16 *)((char *)hdr + mp->m_dirblksize) - 1;
 989         dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 990         /*
 991          * If it's not free or is too short we can't do it.
 992          */
 993         if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG ||
 994             be16_to_cpu(dup->length) < size)
 995                 return 0;
 996
 997         /*
 998          * Start converting it to block form.
 999          */
1000         hdr->magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
1001         needlog = 1;
1002         needscan = 0;
1003         /*
1004          * Use up the space at the end of the block (blp/btp).
1005          */
1006         xfs_dir2_data_use_free(tp, dbp, dup, mp->m_dirblksize - size, size,
1007                 &needlog, &needscan);
1008         /*
1009          * Initialize the block tail.
1010          */
1011         btp = xfs_dir2_block_tail_p(mp, hdr);
1012         btp->count = cpu_to_be32(be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale));
1013         btp->stale = 0;
1014         xfs_dir2_block_log_tail(tp, dbp);
1015         /*
1016          * Initialize the block leaf area.  We compact out stale entries.
1017          */
1018         lep = xfs_dir2_block_leaf_p(btp);
1019         for (from = to = 0; from < be16_to_cpu(leaf->hdr.count); from++) {
1020                 if (leaf->ents[from].address ==
1021                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
1022                         continue;
1023                 lep[to++] = leaf->ents[from];
1024         }
1025         ASSERT(to == be32_to_cpu(btp->count));
1026         xfs_dir2_block_log_leaf(tp, dbp, 0, be32_to_cpu(btp->count) - 1);
1027         /*
1028          * Scan the bestfree if we need it and log the data block header.
1029          */
1030         if (needscan)
1031                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1032         if (needlog)
1033                 xfs_dir2_data_log_header(tp, dbp);
1034         /*
1035          * Pitch the old leaf block.
1036          */
1037         error = xfs_da_shrink_inode(args, mp->m_dirleafblk, lbp);
1038         if (error)
1039                 return error;
1040
1041         /*
1042          * Now see if the resulting block can be shrunken to shortform.
1043          */
1044         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
1045         if (size > XFS_IFORK_DSIZE(dp))
1046                 return 0;
1047
1048         return xfs_dir2_block_to_sf(args, dbp, size, &sfh);
1049 }
1050
1051 /*
1052  * Convert the shortform directory to block form.
1053  */
1054 int                                             /* error */
1055 xfs_dir2_sf_to_block(
1056         xfs_da_args_t           *args)          /* operation arguments */
1057 {
1058         xfs_dir2_db_t           blkno;          /* dir-relative block # (0) */
1059         xfs_dir2_data_hdr_t     *hdr;           /* block header */
1060         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
1061         struct xfs_buf          *bp;            /* block buffer */
1062         xfs_dir2_block_tail_t   *btp;           /* block tail pointer */
1063         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1064         xfs_inode_t             *dp;            /* incore directory inode */
1065         int                     dummy;          /* trash */
1066         xfs_dir2_data_unused_t  *dup;           /* unused entry pointer */
1067         int                     endoffset;      /* end of data objects */
1068         int                     error;          /* error return value */
1069         int                     i;              /* index */
1070         xfs_mount_t             *mp;            /* filesystem mount point */
1071         int                     needlog;        /* need to log block header */
1072         int                     needscan;       /* need to scan block freespc */
1073         int                     newoffset;      /* offset from current entry */
1074         int                     offset;         /* target block offset */
1075         xfs_dir2_sf_entry_t     *sfep;          /* sf entry pointer */
1076         xfs_dir2_sf_hdr_t       *oldsfp;        /* old shortform header  */
1077         xfs_dir2_sf_hdr_t       *sfp;           /* shortform header  */
1078         __be16                  *tagp;          /* end of data entry */
1079         xfs_trans_t             *tp;            /* transaction pointer */
1080         struct xfs_name         name;
1081
1082         trace_xfs_dir2_sf_to_block(args);
1083
1084         dp = args->dp;
1085         tp = args->trans;
1086         mp = dp->i_mount;
1087         ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
1088         /*
1089          * Bomb out if the shortform directory is way too short.
1090          */
1091         if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
1092                 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1093                 return XFS_ERROR(EIO);
1094         }
1095
1096         oldsfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
1097
1098         ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
1099         ASSERT(dp->i_df.if_u1.if_data != NULL);
1100         ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(oldsfp->i8count));
1101
1102         /*
1103          * Copy the directory into a temporary buffer.
1104          * Then pitch the incore inode data so we can make extents.
1105          */
1106         sfp = kmem_alloc(dp->i_df.if_bytes, KM_SLEEP);
1107         memcpy(sfp, oldsfp, dp->i_df.if_bytes);
1108
1109         xfs_idata_realloc(dp, -dp->i_df.if_bytes, XFS_DATA_FORK);
1110         dp->i_d.di_size = 0;
1111         xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1112
1113         /*
1114          * Add block 0 to the inode.
1115          */
1116         error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE, &blkno);
1117         if (error) {
1118                 kmem_free(sfp);
1119                 return error;
1120         }
1121         /*
1122          * Initialize the data block.
1123          */
1124         error = xfs_dir2_data_init(args, blkno, &bp);
1125         if (error) {
1126                 kmem_free(sfp);
1127                 return error;
1128         }
1129         hdr = bp->b_addr;
1130         hdr->magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
1131         /*
1132          * Compute size of block "tail" area.
1133          */
1134         i = (uint)sizeof(*btp) +
1135             (sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t);
1136         /*
1137          * The whole thing is initialized to free by the init routine.
1138          * Say we're using the leaf and tail area.
1139          */
1140         dup = (xfs_dir2_data_unused_t *)(hdr + 1);
1141         needlog = needscan = 0;
1142         xfs_dir2_data_use_free(tp, bp, dup, mp->m_dirblksize - i, i, &needlog,
1143                 &needscan);
1144         ASSERT(needscan == 0);
1145         /*
1146          * Fill in the tail.
1147          */
1148         btp = xfs_dir2_block_tail_p(mp, hdr);
1149         btp->count = cpu_to_be32(sfp->count + 2);       /* ., .. */
1150         btp->stale = 0;
1151         blp = xfs_dir2_block_leaf_p(btp);
1152         endoffset = (uint)((char *)blp - (char *)hdr);
1153         /*
1154          * Remove the freespace, we'll manage it.
1155          */
1156         xfs_dir2_data_use_free(tp, bp, dup,
1157                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
1158                 be16_to_cpu(dup->length), &needlog, &needscan);
1159         /*
1160          * Create entry for .
1161          */
1162         dep = (xfs_dir2_data_entry_t *)
1163               ((char *)hdr + XFS_DIR2_DATA_DOT_OFFSET);
1164         dep->inumber = cpu_to_be64(dp->i_ino);
1165         dep->namelen = 1;
1166         dep->name[0] = '.';
1167         tagp = xfs_dir2_data_entry_tag_p(dep);
1168         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1169         xfs_dir2_data_log_entry(tp, bp, dep);
1170         blp[0].hashval = cpu_to_be32(xfs_dir_hash_dot);
1171         blp[0].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1172                                 (char *)dep - (char *)hdr));
1173         /*
1174          * Create entry for ..
1175          */
1176         dep = (xfs_dir2_data_entry_t *)
1177                 ((char *)hdr + XFS_DIR2_DATA_DOTDOT_OFFSET);
1178         dep->inumber = cpu_to_be64(xfs_dir2_sf_get_parent_ino(sfp));
1179         dep->namelen = 2;
1180         dep->name[0] = dep->name[1] = '.';
1181         tagp = xfs_dir2_data_entry_tag_p(dep);
1182         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1183         xfs_dir2_data_log_entry(tp, bp, dep);
1184         blp[1].hashval = cpu_to_be32(xfs_dir_hash_dotdot);
1185         blp[1].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1186                                 (char *)dep - (char *)hdr));
1187         offset = XFS_DIR2_DATA_FIRST_OFFSET;
1188         /*
1189          * Loop over existing entries, stuff them in.
1190          */
1191         i = 0;
1192         if (!sfp->count)
1193                 sfep = NULL;
1194         else
1195                 sfep = xfs_dir2_sf_firstentry(sfp);
1196         /*
1197          * Need to preserve the existing offset values in the sf directory.
1198          * Insert holes (unused entries) where necessary.
1199          */
1200         while (offset < endoffset) {
1201                 /*
1202                  * sfep is null when we reach the end of the list.
1203                  */
1204                 if (sfep == NULL)
1205                         newoffset = endoffset;
1206                 else
1207                         newoffset = xfs_dir2_sf_get_offset(sfep);
1208                 /*
1209                  * There should be a hole here, make one.
1210                  */
1211                 if (offset < newoffset) {
1212                         dup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
1213                         dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1214                         dup->length = cpu_to_be16(newoffset - offset);
1215                         *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16(
1216                                 ((char *)dup - (char *)hdr));
1217                         xfs_dir2_data_log_unused(tp, bp, dup);
1218                         xfs_dir2_data_freeinsert(hdr, dup, &dummy);
1219                         offset += be16_to_cpu(dup->length);
1220                         continue;
1221                 }
1222                 /*
1223                  * Copy a real entry.
1224                  */
1225                 dep = (xfs_dir2_data_entry_t *)((char *)hdr + newoffset);
1226                 dep->inumber = cpu_to_be64(xfs_dir2_sfe_get_ino(sfp, sfep));
1227                 dep->namelen = sfep->namelen;
1228                 memcpy(dep->name, sfep->name, dep->namelen);
1229                 tagp = xfs_dir2_data_entry_tag_p(dep);
1230                 *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1231                 xfs_dir2_data_log_entry(tp, bp, dep);
1232                 name.name = sfep->name;
1233                 name.len = sfep->namelen;
1234                 blp[2 + i].hashval = cpu_to_be32(mp->m_dirnameops->
1235                                                         hashname(&name));
1236                 blp[2 + i].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1237                                                  (char *)dep - (char *)hdr));
1238                 offset = (int)((char *)(tagp + 1) - (char *)hdr);
1239                 if (++i == sfp->count)
1240                         sfep = NULL;
1241                 else
1242                         sfep = xfs_dir2_sf_nextentry(sfp, sfep);
1243         }
1244         /* Done with the temporary buffer */
1245         kmem_free(sfp);
1246         /*
1247          * Sort the leaf entries by hash value.
1248          */
1249         xfs_sort(blp, be32_to_cpu(btp->count), sizeof(*blp), xfs_dir2_block_sort);
1250         /*
1251          * Log the leaf entry area and tail.
1252          * Already logged the header in data_init, ignore needlog.
1253          */
1254         ASSERT(needscan == 0);
1255         xfs_dir2_block_log_leaf(tp, bp, 0, be32_to_cpu(btp->count) - 1);
1256         xfs_dir2_block_log_tail(tp, bp);
1257         xfs_dir2_data_check(dp, bp);
1258         return 0;
1259 }