fs/xfs/xfs_dir2_block.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3  * Copyright (c) 2013 Red Hat, Inc.
   4  * All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it would be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write the Free Software Foundation,
  17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 #include "xfs.h"
  20 #include "xfs_fs.h"
  21 #include "xfs_types.h"
  22 #include "xfs_log.h"
  23 #include "xfs_trans.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_ag.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_da_btree.h"
  28 #include "xfs_bmap_btree.h"
  29 #include "xfs_dinode.h"
  30 #include "xfs_inode.h"
  31 #include "xfs_inode_item.h"
  32 #include "xfs_buf_item.h"
  33 #include "xfs_dir2.h"
  34 #include "xfs_dir2_format.h"
  35 #include "xfs_dir2_priv.h"
  36 #include "xfs_error.h"
  37 #include "xfs_trace.h"
  38 #include "xfs_cksum.h"
  39
  40 /*
  41  * Local function prototypes.
  42  */
  43 static void xfs_dir2_block_log_leaf(xfs_trans_t *tp, struct xfs_buf *bp,
  44                                     int first, int last);
  45 static void xfs_dir2_block_log_tail(xfs_trans_t *tp, struct xfs_buf *bp);
  46 static int xfs_dir2_block_lookup_int(xfs_da_args_t *args, struct xfs_buf **bpp,
  47                                      int *entno);
  48 static int xfs_dir2_block_sort(const void *a, const void *b);
  49
  50 static xfs_dahash_t xfs_dir_hash_dot, xfs_dir_hash_dotdot;
  51
  52 /*
  53  * One-time startup routine called from xfs_init().
  54  */
  55 void
  56 xfs_dir_startup(void)
  57 {
  58         xfs_dir_hash_dot = xfs_da_hashname((unsigned char *)".", 1);
  59         xfs_dir_hash_dotdot = xfs_da_hashname((unsigned char *)"..", 2);
  60 }
  61
  62 static bool
  63 xfs_dir3_block_verify(
  64         struct xfs_buf          *bp)
  65 {
  66         struct xfs_mount        *mp = bp->b_target->bt_mount;
  67         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  68
  69         if (xfs_sb_version_hascrc(&mp->m_sb)) {
  70                 if (hdr3->magic != cpu_to_be32(XFS_DIR3_BLOCK_MAGIC))
  71                         return false;
  72                 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_uuid))
  73                         return false;
  74                 if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
  75                         return false;
  76         } else {
  77                 if (hdr3->magic != cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
  78                         return false;
  79         }
  80         if (__xfs_dir3_data_check(NULL, bp))
  81                 return false;
  82         return true;
  83 }
  84
  85 static void
  86 xfs_dir3_block_read_verify(
  87         struct xfs_buf  *bp)
  88 {
  89         struct xfs_mount        *mp = bp->b_target->bt_mount;
  90
  91         if ((xfs_sb_version_hascrc(&mp->m_sb) &&
  92              !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
  93                                           XFS_DIR3_DATA_CRC_OFF)) ||
  94             !xfs_dir3_block_verify(bp)) {
  95                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
  96                 xfs_buf_ioerror(bp, EFSCORRUPTED);
  97         }
  98 }
  99
 100 static void
 101 xfs_dir3_block_write_verify(
 102         struct xfs_buf  *bp)
 103 {
 104         struct xfs_mount        *mp = bp->b_target->bt_mount;
 105         struct xfs_buf_log_item *bip = bp->b_fspriv;
 106         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 107
 108         if (!xfs_dir3_block_verify(bp)) {
 109                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 110                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 111                 return;
 112         }
 113
 114         if (!xfs_sb_version_hascrc(&mp->m_sb))
 115                 return;
 116
 117         if (bip)
 118                 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
 119
 120         xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_DATA_CRC_OFF);
 121 }
 122
 123 const struct xfs_buf_ops xfs_dir3_block_buf_ops = {
 124         .verify_read = xfs_dir3_block_read_verify,
 125         .verify_write = xfs_dir3_block_write_verify,
 126 };
 127
 128 static int
 129 xfs_dir3_block_read(
 130         struct xfs_trans        *tp,
 131         struct xfs_inode        *dp,
 132         struct xfs_buf          **bpp)
 133 {
 134         struct xfs_mount        *mp = dp->i_mount;
 135         int                     err;
 136
 137         err = xfs_da_read_buf(tp, dp, mp->m_dirdatablk, -1, bpp,
 138                                 XFS_DATA_FORK, &xfs_dir3_block_buf_ops);
 139         if (!err && tp)
 140                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_BLOCK_BUF);
 141         return err;
 142 }
 143
 144 static void
 145 xfs_dir3_block_init(
 146         struct xfs_mount        *mp,
 147         struct xfs_trans        *tp,
 148         struct xfs_buf          *bp,
 149         struct xfs_inode        *dp)
 150 {
 151         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 152
 153         bp->b_ops = &xfs_dir3_block_buf_ops;
 154         xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_BLOCK_BUF);
 155
 156         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 157                 memset(hdr3, 0, sizeof(*hdr3));
 158                 hdr3->magic = cpu_to_be32(XFS_DIR3_BLOCK_MAGIC);
 159                 hdr3->blkno = cpu_to_be64(bp->b_bn);
 160                 hdr3->owner = cpu_to_be64(dp->i_ino);
 161                 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_uuid);
 162                 return;
 163
 164         }
 165         hdr3->magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
 166 }
 167
 168 static void
 169 xfs_dir2_block_need_space(
 170         struct xfs_dir2_data_hdr        *hdr,
 171         struct xfs_dir2_block_tail      *btp,
 172         struct xfs_dir2_leaf_entry      *blp,
 173         __be16                          **tagpp,
 174         struct xfs_dir2_data_unused     **dupp,
 175         struct xfs_dir2_data_unused     **enddupp,
 176         int                             *compact,
 177         int                             len)
 178 {
 179         struct xfs_dir2_data_free       *bf;
 180         __be16                          *tagp = NULL;
 181         struct xfs_dir2_data_unused     *dup = NULL;
 182         struct xfs_dir2_data_unused     *enddup = NULL;
 183
 184         *compact = 0;
 185         bf = xfs_dir3_data_bestfree_p(hdr);
 186
 187         /*
 188          * If there are stale entries we'll use one for the leaf.
 189          */
 190         if (btp->stale) {
 191                 if (be16_to_cpu(bf[0].length) >= len) {
 192                         /*
 193                          * The biggest entry enough to avoid compaction.
 194                          */
 195                         dup = (xfs_dir2_data_unused_t *)
 196                               ((char *)hdr + be16_to_cpu(bf[0].offset));
 197                         goto out;
 198                 }
 199
 200                 /*
 201                  * Will need to compact to make this work.
 202                  * Tag just before the first leaf entry.
 203                  */
 204                 *compact = 1;
 205                 tagp = (__be16 *)blp - 1;
 206
 207                 /* Data object just before the first leaf entry.  */
 208                 dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 209
 210                 /*
 211                  * If it's not free then the data will go where the
 212                  * leaf data starts now, if it works at all.
 213                  */
 214                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 215                         if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
 216                             (uint)sizeof(*blp) < len)
 217                                 dup = NULL;
 218                 } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
 219                         dup = NULL;
 220                 else
 221                         dup = (xfs_dir2_data_unused_t *)blp;
 222                 goto out;
 223         }
 224
 225         /*
 226          * no stale entries, so just use free space.
 227          * Tag just before the first leaf entry.
 228          */
 229         tagp = (__be16 *)blp - 1;
 230
 231         /* Data object just before the first leaf entry.  */
 232         enddup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 233
 234         /*
 235          * If it's not free then can't do this add without cleaning up:
 236          * the space before the first leaf entry needs to be free so it
 237          * can be expanded to hold the pointer to the new entry.
 238          */
 239         if (be16_to_cpu(enddup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 240                 /*
 241                  * Check out the biggest freespace and see if it's the same one.
 242                  */
 243                 dup = (xfs_dir2_data_unused_t *)
 244                       ((char *)hdr + be16_to_cpu(bf[0].offset));
 245                 if (dup != enddup) {
 246                         /*
 247                          * Not the same free entry, just check its length.
 248                          */
 249                         if (be16_to_cpu(dup->length) < len)
 250                                 dup = NULL;
 251                         goto out;
 252                 }
 253
 254                 /*
 255                  * It is the biggest freespace, can it hold the leaf too?
 256                  */
 257                 if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
 258                         /*
 259                          * Yes, use the second-largest entry instead if it works.
 260                          */
 261                         if (be16_to_cpu(bf[1].length) >= len)
 262                                 dup = (xfs_dir2_data_unused_t *)
 263                                       ((char *)hdr + be16_to_cpu(bf[1].offset));
 264                         else
 265                                 dup = NULL;
 266                 }
 267         }
 268 out:
 269         *tagpp = tagp;
 270         *dupp = dup;
 271         *enddupp = enddup;
 272 }
 273
 274 /*
 275  * compact the leaf entries.
 276  * Leave the highest-numbered stale entry stale.
 277  * XXX should be the one closest to mid but mid is not yet computed.
 278  */
 279 static void
 280 xfs_dir2_block_compact(
 281         struct xfs_trans                *tp,
 282         struct xfs_buf                  *bp,
 283         struct xfs_dir2_data_hdr        *hdr,
 284         struct xfs_dir2_block_tail      *btp,
 285         struct xfs_dir2_leaf_entry      *blp,
 286         int                             *needlog,
 287         int                             *lfloghigh,
 288         int                             *lfloglow)
 289 {
 290         int                     fromidx;        /* source leaf index */
 291         int                     toidx;          /* target leaf index */
 292         int                     needscan = 0;
 293         int                     highstale;      /* high stale index */
 294
 295         fromidx = toidx = be32_to_cpu(btp->count) - 1;
 296         highstale = *lfloghigh = -1;
 297         for (; fromidx >= 0; fromidx--) {
 298                 if (blp[fromidx].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
 299                         if (highstale == -1)
 300                                 highstale = toidx;
 301                         else {
 302                                 if (*lfloghigh == -1)
 303                                         *lfloghigh = toidx;
 304                                 continue;
 305                         }
 306                 }
 307                 if (fromidx < toidx)
 308                         blp[toidx] = blp[fromidx];
 309                 toidx--;
 310         }
 311         *lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
 312         *lfloghigh -= be32_to_cpu(btp->stale) - 1;
 313         be32_add_cpu(&btp->count, -(be32_to_cpu(btp->stale) - 1));
 314         xfs_dir2_data_make_free(tp, bp,
 315                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 316                 (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
 317                 needlog, &needscan);
 318         blp += be32_to_cpu(btp->stale) - 1;
 319         btp->stale = cpu_to_be32(1);
 320         /*
 321          * If we now need to rebuild the bestfree map, do so.
 322          * This needs to happen before the next call to use_free.
 323          */
 324         if (needscan)
 325                 xfs_dir2_data_freescan(tp->t_mountp, hdr, needlog);
 326 }
 327
 328 /*
 329  * Add an entry to a block directory.
 330  */
 331 int                                             /* error */
 332 xfs_dir2_block_addname(
 333         xfs_da_args_t           *args)          /* directory op arguments */
 334 {
 335         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 336         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 337         struct xfs_buf          *bp;            /* buffer for block */
 338         xfs_dir2_block_tail_t   *btp;           /* block tail */
 339         int                     compact;        /* need to compact leaf ents */
 340         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 341         xfs_inode_t             *dp;            /* directory inode */
 342         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 343         int                     error;          /* error return value */
 344         xfs_dir2_data_unused_t  *enddup=NULL;   /* unused at end of data */
 345         xfs_dahash_t            hash;           /* hash value of found entry */
 346         int                     high;           /* high index for binary srch */
 347         int                     highstale;      /* high stale index */
 348         int                     lfloghigh=0;    /* last final leaf to log */
 349         int                     lfloglow=0;     /* first final leaf to log */
 350         int                     len;            /* length of the new entry */
 351         int                     low;            /* low index for binary srch */
 352         int                     lowstale;       /* low stale index */
 353         int                     mid=0;          /* midpoint for binary srch */
 354         xfs_mount_t             *mp;            /* filesystem mount point */
 355         int                     needlog;        /* need to log header */
 356         int                     needscan;       /* need to rescan freespace */
 357         __be16                  *tagp;          /* pointer to tag value */
 358         xfs_trans_t             *tp;            /* transaction structure */
 359
 360         trace_xfs_dir2_block_addname(args);
 361
 362         dp = args->dp;
 363         tp = args->trans;
 364         mp = dp->i_mount;
 365
 366         /* Read the (one and only) directory block into bp. */
 367         error = xfs_dir3_block_read(tp, dp, &bp);
 368         if (error)
 369                 return error;
 370
 371         len = xfs_dir2_data_entsize(args->namelen);
 372
 373         /*
 374          * Set up pointers to parts of the block.
 375          */
 376         hdr = bp->b_addr;
 377         btp = xfs_dir2_block_tail_p(mp, hdr);
 378         blp = xfs_dir2_block_leaf_p(btp);
 379
 380         /*
 381          * Find out if we can reuse stale entries or whether we need extra
 382          * space for entry and new leaf.
 383          */
 384         xfs_dir2_block_need_space(hdr, btp, blp, &tagp, &dup,
 385                                   &enddup, &compact, len);
 386
 387         /*
 388          * Done everything we need for a space check now.
 389          */
 390         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 391                 xfs_trans_brelse(tp, bp);
 392                 if (!dup)
 393                         return XFS_ERROR(ENOSPC);
 394                 return 0;
 395         }
 396
 397         /*
 398          * If we don't have space for the new entry & leaf ...
 399          */
 400         if (!dup) {
 401                 /* Don't have a space reservation: return no-space.  */
 402                 if (args->total == 0)
 403                         return XFS_ERROR(ENOSPC);
 404                 /*
 405                  * Convert to the next larger format.
 406                  * Then add the new entry in that format.
 407                  */
 408                 error = xfs_dir2_block_to_leaf(args, bp);
 409                 if (error)
 410                         return error;
 411                 return xfs_dir2_leaf_addname(args);
 412         }
 413
 414         needlog = needscan = 0;
 415
 416         /*
 417          * If need to compact the leaf entries, do it now.
 418          */
 419         if (compact) {
 420                 xfs_dir2_block_compact(tp, bp, hdr, btp, blp, &needlog,
 421                                       &lfloghigh, &lfloglow);
 422                 /* recalculate blp post-compaction */
 423                 blp = xfs_dir2_block_leaf_p(btp);
 424         } else if (btp->stale) {
 425                 /*
 426                  * Set leaf logging boundaries to impossible state.
 427                  * For the no-stale case they're set explicitly.
 428                  */
 429                 lfloglow = be32_to_cpu(btp->count);
 430                 lfloghigh = -1;
 431         }
 432
 433         /*
 434          * Find the slot that's first lower than our hash value, -1 if none.
 435          */
 436         for (low = 0, high = be32_to_cpu(btp->count) - 1; low <= high; ) {
 437                 mid = (low + high) >> 1;
 438                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 439                         break;
 440                 if (hash < args->hashval)
 441                         low = mid + 1;
 442                 else
 443                         high = mid - 1;
 444         }
 445         while (mid >= 0 && be32_to_cpu(blp[mid].hashval) >= args->hashval) {
 446                 mid--;
 447         }
 448         /*
 449          * No stale entries, will use enddup space to hold new leaf.
 450          */
 451         if (!btp->stale) {
 452                 /*
 453                  * Mark the space needed for the new leaf entry, now in use.
 454                  */
 455                 xfs_dir2_data_use_free(tp, bp, enddup,
 456                         (xfs_dir2_data_aoff_t)
 457                         ((char *)enddup - (char *)hdr + be16_to_cpu(enddup->length) -
 458                          sizeof(*blp)),
 459                         (xfs_dir2_data_aoff_t)sizeof(*blp),
 460                         &needlog, &needscan);
 461                 /*
 462                  * Update the tail (entry count).
 463                  */
 464                 be32_add_cpu(&btp->count, 1);
 465                 /*
 466                  * If we now need to rebuild the bestfree map, do so.
 467                  * This needs to happen before the next call to use_free.
 468                  */
 469                 if (needscan) {
 470                         xfs_dir2_data_freescan(mp, hdr, &needlog);
 471                         needscan = 0;
 472                 }
 473                 /*
 474                  * Adjust pointer to the first leaf entry, we're about to move
 475                  * the table up one to open up space for the new leaf entry.
 476                  * Then adjust our index to match.
 477                  */
 478                 blp--;
 479                 mid++;
 480                 if (mid)
 481                         memmove(blp, &blp[1], mid * sizeof(*blp));
 482                 lfloglow = 0;
 483                 lfloghigh = mid;
 484         }
 485         /*
 486          * Use a stale leaf for our new entry.
 487          */
 488         else {
 489                 for (lowstale = mid;
 490                      lowstale >= 0 &&
 491                         blp[lowstale].address !=
 492                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 493                      lowstale--)
 494                         continue;
 495                 for (highstale = mid + 1;
 496                      highstale < be32_to_cpu(btp->count) &&
 497                         blp[highstale].address !=
 498                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR) &&
 499                         (lowstale < 0 || mid - lowstale > highstale - mid);
 500                      highstale++)
 501                         continue;
 502                 /*
 503                  * Move entries toward the low-numbered stale entry.
 504                  */
 505                 if (lowstale >= 0 &&
 506                     (highstale == be32_to_cpu(btp->count) ||
 507                      mid - lowstale <= highstale - mid)) {
 508                         if (mid - lowstale)
 509                                 memmove(&blp[lowstale], &blp[lowstale + 1],
 510                                         (mid - lowstale) * sizeof(*blp));
 511                         lfloglow = MIN(lowstale, lfloglow);
 512                         lfloghigh = MAX(mid, lfloghigh);
 513                 }
 514                 /*
 515                  * Move entries toward the high-numbered stale entry.
 516                  */
 517                 else {
 518                         ASSERT(highstale < be32_to_cpu(btp->count));
 519                         mid++;
 520                         if (highstale - mid)
 521                                 memmove(&blp[mid + 1], &blp[mid],
 522                                         (highstale - mid) * sizeof(*blp));
 523                         lfloglow = MIN(mid, lfloglow);
 524                         lfloghigh = MAX(highstale, lfloghigh);
 525                 }
 526                 be32_add_cpu(&btp->stale, -1);
 527         }
 528         /*
 529          * Point to the new data entry.
 530          */
 531         dep = (xfs_dir2_data_entry_t *)dup;
 532         /*
 533          * Fill in the leaf entry.
 534          */
 535         blp[mid].hashval = cpu_to_be32(args->hashval);
 536         blp[mid].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
 537                                 (char *)dep - (char *)hdr));
 538         xfs_dir2_block_log_leaf(tp, bp, lfloglow, lfloghigh);
 539         /*
 540          * Mark space for the data entry used.
 541          */
 542         xfs_dir2_data_use_free(tp, bp, dup,
 543                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
 544                 (xfs_dir2_data_aoff_t)len, &needlog, &needscan);
 545         /*
 546          * Create the new data entry.
 547          */
 548         dep->inumber = cpu_to_be64(args->inumber);
 549         dep->namelen = args->namelen;
 550         memcpy(dep->name, args->name, args->namelen);
 551         tagp = xfs_dir2_data_entry_tag_p(dep);
 552         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 553         /*
 554          * Clean up the bestfree array and log the header, tail, and entry.
 555          */
 556         if (needscan)
 557                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 558         if (needlog)
 559                 xfs_dir2_data_log_header(tp, bp);
 560         xfs_dir2_block_log_tail(tp, bp);
 561         xfs_dir2_data_log_entry(tp, bp, dep);
 562         xfs_dir3_data_check(dp, bp);
 563         return 0;
 564 }
 565
 566 /*
 567  * Readdir for block directories.
 568  */
 569 int                                             /* error */
 570 xfs_dir2_block_getdents(
 571         xfs_inode_t             *dp,            /* incore inode */
 572         struct dir_context      *ctx)
 573 {
 574         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 575         struct xfs_buf          *bp;            /* buffer for block */
 576         xfs_dir2_block_tail_t   *btp;           /* block tail */
 577         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 578         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 579         char                    *endptr;        /* end of the data entries */
 580         int                     error;          /* error return value */
 581         xfs_mount_t             *mp;            /* filesystem mount point */
 582         char                    *ptr;           /* current data entry */
 583         int                     wantoff;        /* starting block offset */
 584         xfs_off_t               cook;
 585
 586         mp = dp->i_mount;
 587         /*
 588          * If the block number in the offset is out of range, we're done.
 589          */
 590         if (xfs_dir2_dataptr_to_db(mp, ctx->pos) > mp->m_dirdatablk)
 591                 return 0;
 592
 593         error = xfs_dir3_block_read(NULL, dp, &bp);
 594         if (error)
 595                 return error;
 596
 597         /*
 598          * Extract the byte offset we start at from the seek pointer.
 599          * We'll skip entries before this.
 600          */
 601         wantoff = xfs_dir2_dataptr_to_off(mp, ctx->pos);
 602         hdr = bp->b_addr;
 603         xfs_dir3_data_check(dp, bp);
 604         /*
 605          * Set up values for the loop.
 606          */
 607         btp = xfs_dir2_block_tail_p(mp, hdr);
 608         ptr = (char *)xfs_dir3_data_entry_p(hdr);
 609         endptr = (char *)xfs_dir2_block_leaf_p(btp);
 610
 611         /*
 612          * Loop over the data portion of the block.
 613          * Each object is a real entry (dep) or an unused one (dup).
 614          */
 615         while (ptr < endptr) {
 616                 dup = (xfs_dir2_data_unused_t *)ptr;
 617                 /*
 618                  * Unused, skip it.
 619                  */
 620                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 621                         ptr += be16_to_cpu(dup->length);
 622                         continue;
 623                 }
 624
 625                 dep = (xfs_dir2_data_entry_t *)ptr;
 626
 627                 /*
 628                  * Bump pointer for the next iteration.
 629                  */
 630                 ptr += xfs_dir2_data_entsize(dep->namelen);
 631                 /*
 632                  * The entry is before the desired starting point, skip it.
 633                  */
 634                 if ((char *)dep - (char *)hdr < wantoff)
 635                         continue;
 636
 637                 cook = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk,
 638                                             (char *)dep - (char *)hdr);
 639
 640                 ctx->pos = cook & 0x7fffffff;
 641                 /*
 642                  * If it didn't fit, set the final offset to here & return.
 643                  */
 644                 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
 645                             be64_to_cpu(dep->inumber), DT_UNKNOWN)) {
 646                         xfs_trans_brelse(NULL, bp);
 647                         return 0;
 648                 }
 649         }
 650
 651         /*
 652          * Reached the end of the block.
 653          * Set the offset to a non-existent block 1 and return.
 654          */
 655         ctx->pos = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk + 1, 0) &
 656                         0x7fffffff;
 657         xfs_trans_brelse(NULL, bp);
 658         return 0;
 659 }
 660
 661 /*
 662  * Log leaf entries from the block.
 663  */
 664 static void
 665 xfs_dir2_block_log_leaf(
 666         xfs_trans_t             *tp,            /* transaction structure */
 667         struct xfs_buf          *bp,            /* block buffer */
 668         int                     first,          /* index of first logged leaf */
 669         int                     last)           /* index of last logged leaf */
 670 {
 671         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 672         xfs_dir2_leaf_entry_t   *blp;
 673         xfs_dir2_block_tail_t   *btp;
 674
 675         btp = xfs_dir2_block_tail_p(tp->t_mountp, hdr);
 676         blp = xfs_dir2_block_leaf_p(btp);
 677         xfs_trans_log_buf(tp, bp, (uint)((char *)&blp[first] - (char *)hdr),
 678                 (uint)((char *)&blp[last + 1] - (char *)hdr - 1));
 679 }
 680
 681 /*
 682  * Log the block tail.
 683  */
 684 static void
 685 xfs_dir2_block_log_tail(
 686         xfs_trans_t             *tp,            /* transaction structure */
 687         struct xfs_buf          *bp)            /* block buffer */
 688 {
 689         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 690         xfs_dir2_block_tail_t   *btp;
 691
 692         btp = xfs_dir2_block_tail_p(tp->t_mountp, hdr);
 693         xfs_trans_log_buf(tp, bp, (uint)((char *)btp - (char *)hdr),
 694                 (uint)((char *)(btp + 1) - (char *)hdr - 1));
 695 }
 696
 697 /*
 698  * Look up an entry in the block.  This is the external routine,
 699  * xfs_dir2_block_lookup_int does the real work.
 700  */
 701 int                                             /* error */
 702 xfs_dir2_block_lookup(
 703         xfs_da_args_t           *args)          /* dir lookup arguments */
 704 {
 705         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 706         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 707         struct xfs_buf          *bp;            /* block buffer */
 708         xfs_dir2_block_tail_t   *btp;           /* block tail */
 709         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 710         xfs_inode_t             *dp;            /* incore inode */
 711         int                     ent;            /* entry index */
 712         int                     error;          /* error return value */
 713         xfs_mount_t             *mp;            /* filesystem mount point */
 714
 715         trace_xfs_dir2_block_lookup(args);
 716
 717         /*
 718          * Get the buffer, look up the entry.
 719          * If not found (ENOENT) then return, have no buffer.
 720          */
 721         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent)))
 722                 return error;
 723         dp = args->dp;
 724         mp = dp->i_mount;
 725         hdr = bp->b_addr;
 726         xfs_dir3_data_check(dp, bp);
 727         btp = xfs_dir2_block_tail_p(mp, hdr);
 728         blp = xfs_dir2_block_leaf_p(btp);
 729         /*
 730          * Get the offset from the leaf entry, to point to the data.
 731          */
 732         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
 733                 xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 734         /*
 735          * Fill in inode number, CI name if appropriate, release the block.
 736          */
 737         args->inumber = be64_to_cpu(dep->inumber);
 738         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
 739         xfs_trans_brelse(args->trans, bp);
 740         return XFS_ERROR(error);
 741 }
 742
 743 /*
 744  * Internal block lookup routine.
 745  */
 746 static int                                      /* error */
 747 xfs_dir2_block_lookup_int(
 748         xfs_da_args_t           *args,          /* dir lookup arguments */
 749         struct xfs_buf          **bpp,          /* returned block buffer */
 750         int                     *entno)         /* returned entry number */
 751 {
 752         xfs_dir2_dataptr_t      addr;           /* data entry address */
 753         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 754         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 755         struct xfs_buf          *bp;            /* block buffer */
 756         xfs_dir2_block_tail_t   *btp;           /* block tail */
 757         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 758         xfs_inode_t             *dp;            /* incore inode */
 759         int                     error;          /* error return value */
 760         xfs_dahash_t            hash;           /* found hash value */
 761         int                     high;           /* binary search high index */
 762         int                     low;            /* binary search low index */
 763         int                     mid;            /* binary search current idx */
 764         xfs_mount_t             *mp;            /* filesystem mount point */
 765         xfs_trans_t             *tp;            /* transaction pointer */
 766         enum xfs_dacmp          cmp;            /* comparison result */
 767
 768         dp = args->dp;
 769         tp = args->trans;
 770         mp = dp->i_mount;
 771
 772         error = xfs_dir3_block_read(tp, dp, &bp);
 773         if (error)
 774                 return error;
 775
 776         hdr = bp->b_addr;
 777         xfs_dir3_data_check(dp, bp);
 778         btp = xfs_dir2_block_tail_p(mp, hdr);
 779         blp = xfs_dir2_block_leaf_p(btp);
 780         /*
 781          * Loop doing a binary search for our hash value.
 782          * Find our entry, ENOENT if it's not there.
 783          */
 784         for (low = 0, high = be32_to_cpu(btp->count) - 1; ; ) {
 785                 ASSERT(low <= high);
 786                 mid = (low + high) >> 1;
 787                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 788                         break;
 789                 if (hash < args->hashval)
 790                         low = mid + 1;
 791                 else
 792                         high = mid - 1;
 793                 if (low > high) {
 794                         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 795                         xfs_trans_brelse(tp, bp);
 796                         return XFS_ERROR(ENOENT);
 797                 }
 798         }
 799         /*
 800          * Back up to the first one with the right hash value.
 801          */
 802         while (mid > 0 && be32_to_cpu(blp[mid - 1].hashval) == args->hashval) {
 803                 mid--;
 804         }
 805         /*
 806          * Now loop forward through all the entries with the
 807          * right hash value looking for our name.
 808          */
 809         do {
 810                 if ((addr = be32_to_cpu(blp[mid].address)) == XFS_DIR2_NULL_DATAPTR)
 811                         continue;
 812                 /*
 813                  * Get pointer to the entry from the leaf.
 814                  */
 815                 dep = (xfs_dir2_data_entry_t *)
 816                         ((char *)hdr + xfs_dir2_dataptr_to_off(mp, addr));
 817                 /*
 818                  * Compare name and if it's an exact match, return the index
 819                  * and buffer. If it's the first case-insensitive match, store
 820                  * the index and buffer and continue looking for an exact match.
 821                  */
 822                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 823                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 824                         args->cmpresult = cmp;
 825                         *bpp = bp;
 826                         *entno = mid;
 827                         if (cmp == XFS_CMP_EXACT)
 828                                 return 0;
 829                 }
 830         } while (++mid < be32_to_cpu(btp->count) &&
 831                         be32_to_cpu(blp[mid].hashval) == hash);
 832
 833         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 834         /*
 835          * Here, we can only be doing a lookup (not a rename or replace).
 836          * If a case-insensitive match was found earlier, return success.
 837          */
 838         if (args->cmpresult == XFS_CMP_CASE)
 839                 return 0;
 840         /*
 841          * No match, release the buffer and return ENOENT.
 842          */
 843         xfs_trans_brelse(tp, bp);
 844         return XFS_ERROR(ENOENT);
 845 }
 846
 847 /*
 848  * Remove an entry from a block format directory.
 849  * If that makes the block small enough to fit in shortform, transform it.
 850  */
 851 int                                             /* error */
 852 xfs_dir2_block_removename(
 853         xfs_da_args_t           *args)          /* directory operation args */
 854 {
 855         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 856         xfs_dir2_leaf_entry_t   *blp;           /* block leaf pointer */
 857         struct xfs_buf          *bp;            /* block buffer */
 858         xfs_dir2_block_tail_t   *btp;           /* block tail */
 859         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 860         xfs_inode_t             *dp;            /* incore inode */
 861         int                     ent;            /* block leaf entry index */
 862         int                     error;          /* error return value */
 863         xfs_mount_t             *mp;            /* filesystem mount point */
 864         int                     needlog;        /* need to log block header */
 865         int                     needscan;       /* need to fixup bestfree */
 866         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 867         int                     size;           /* shortform size */
 868         xfs_trans_t             *tp;            /* transaction pointer */
 869
 870         trace_xfs_dir2_block_removename(args);
 871
 872         /*
 873          * Look up the entry in the block.  Gets the buffer and entry index.
 874          * It will always be there, the vnodeops level does a lookup first.
 875          */
 876         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 877                 return error;
 878         }
 879         dp = args->dp;
 880         tp = args->trans;
 881         mp = dp->i_mount;
 882         hdr = bp->b_addr;
 883         btp = xfs_dir2_block_tail_p(mp, hdr);
 884         blp = xfs_dir2_block_leaf_p(btp);
 885         /*
 886          * Point to the data entry using the leaf entry.
 887          */
 888         dep = (xfs_dir2_data_entry_t *)
 889               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 890         /*
 891          * Mark the data entry's space free.
 892          */
 893         needlog = needscan = 0;
 894         xfs_dir2_data_make_free(tp, bp,
 895                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
 896                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
 897         /*
 898          * Fix up the block tail.
 899          */
 900         be32_add_cpu(&btp->stale, 1);
 901         xfs_dir2_block_log_tail(tp, bp);
 902         /*
 903          * Remove the leaf entry by marking it stale.
 904          */
 905         blp[ent].address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 906         xfs_dir2_block_log_leaf(tp, bp, ent, ent);
 907         /*
 908          * Fix up bestfree, log the header if necessary.
 909          */
 910         if (needscan)
 911                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 912         if (needlog)
 913                 xfs_dir2_data_log_header(tp, bp);
 914         xfs_dir3_data_check(dp, bp);
 915         /*
 916          * See if the size as a shortform is good enough.
 917          */
 918         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
 919         if (size > XFS_IFORK_DSIZE(dp))
 920                 return 0;
 921
 922         /*
 923          * If it works, do the conversion.
 924          */
 925         return xfs_dir2_block_to_sf(args, bp, size, &sfh);
 926 }
 927
 928 /*
 929  * Replace an entry in a V2 block directory.
 930  * Change the inode number to the new value.
 931  */
 932 int                                             /* error */
 933 xfs_dir2_block_replace(
 934         xfs_da_args_t           *args)          /* directory operation args */
 935 {
 936         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 937         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 938         struct xfs_buf          *bp;            /* block buffer */
 939         xfs_dir2_block_tail_t   *btp;           /* block tail */
 940         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 941         xfs_inode_t             *dp;            /* incore inode */
 942         int                     ent;            /* leaf entry index */
 943         int                     error;          /* error return value */
 944         xfs_mount_t             *mp;            /* filesystem mount point */
 945
 946         trace_xfs_dir2_block_replace(args);
 947
 948         /*
 949          * Lookup the entry in the directory.  Get buffer and entry index.
 950          * This will always succeed since the caller has already done a lookup.
 951          */
 952         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 953                 return error;
 954         }
 955         dp = args->dp;
 956         mp = dp->i_mount;
 957         hdr = bp->b_addr;
 958         btp = xfs_dir2_block_tail_p(mp, hdr);
 959         blp = xfs_dir2_block_leaf_p(btp);
 960         /*
 961          * Point to the data entry we need to change.
 962          */
 963         dep = (xfs_dir2_data_entry_t *)
 964               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
 965         ASSERT(be64_to_cpu(dep->inumber) != args->inumber);
 966         /*
 967          * Change the inode number to the new value.
 968          */
 969         dep->inumber = cpu_to_be64(args->inumber);
 970         xfs_dir2_data_log_entry(args->trans, bp, dep);
 971         xfs_dir3_data_check(dp, bp);
 972         return 0;
 973 }
 974
 975 /*
 976  * Qsort comparison routine for the block leaf entries.
 977  */
 978 static int                                      /* sort order */
 979 xfs_dir2_block_sort(
 980         const void                      *a,     /* first leaf entry */
 981         const void                      *b)     /* second leaf entry */
 982 {
 983         const xfs_dir2_leaf_entry_t     *la;    /* first leaf entry */
 984         const xfs_dir2_leaf_entry_t     *lb;    /* second leaf entry */
 985
 986         la = a;
 987         lb = b;
 988         return be32_to_cpu(la->hashval) < be32_to_cpu(lb->hashval) ? -1 :
 989                 (be32_to_cpu(la->hashval) > be32_to_cpu(lb->hashval) ? 1 : 0);
 990 }
 991
 992 /*
 993  * Convert a V2 leaf directory to a V2 block directory if possible.
 994  */
 995 int                                             /* error */
 996 xfs_dir2_leaf_to_block(
 997         xfs_da_args_t           *args,          /* operation arguments */
 998         struct xfs_buf          *lbp,           /* leaf buffer */
 999         struct xfs_buf          *dbp)           /* data buffer */
1000 {
1001         __be16                  *bestsp;        /* leaf bests table */
1002         xfs_dir2_data_hdr_t     *hdr;           /* block header */
1003         xfs_dir2_block_tail_t   *btp;           /* block tail */
1004         xfs_inode_t             *dp;            /* incore directory inode */
1005         xfs_dir2_data_unused_t  *dup;           /* unused data entry */
1006         int                     error;          /* error return value */
1007         int                     from;           /* leaf from index */
1008         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1009         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1010         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1011         xfs_mount_t             *mp;            /* file system mount point */
1012         int                     needlog;        /* need to log data header */
1013         int                     needscan;       /* need to scan for bestfree */
1014         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
1015         int                     size;           /* bytes used */
1016         __be16                  *tagp;          /* end of entry (tag) */
1017         int                     to;             /* block/leaf to index */
1018         xfs_trans_t             *tp;            /* transaction pointer */
1019         struct xfs_dir2_leaf_entry *ents;
1020         struct xfs_dir3_icleaf_hdr leafhdr;
1021
1022         trace_xfs_dir2_leaf_to_block(args);
1023
1024         dp = args->dp;
1025         tp = args->trans;
1026         mp = dp->i_mount;
1027         leaf = lbp->b_addr;
1028         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1029         ents = xfs_dir3_leaf_ents_p(leaf);
1030         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1031
1032         ASSERT(leafhdr.magic == XFS_DIR2_LEAF1_MAGIC ||
1033                leafhdr.magic == XFS_DIR3_LEAF1_MAGIC);
1034         /*
1035          * If there are data blocks other than the first one, take this
1036          * opportunity to remove trailing empty data blocks that may have
1037          * been left behind during no-space-reservation operations.
1038          * These will show up in the leaf bests table.
1039          */
1040         while (dp->i_d.di_size > mp->m_dirblksize) {
1041                 int hdrsz;
1042
1043                 hdrsz = xfs_dir3_data_hdr_size(xfs_sb_version_hascrc(&mp->m_sb));
1044                 bestsp = xfs_dir2_leaf_bests_p(ltp);
1045                 if (be16_to_cpu(bestsp[be32_to_cpu(ltp->bestcount) - 1]) ==
1046                                             mp->m_dirblksize - hdrsz) {
1047                         if ((error =
1048                             xfs_dir2_leaf_trim_data(args, lbp,
1049                                     (xfs_dir2_db_t)(be32_to_cpu(ltp->bestcount) - 1))))
1050                                 return error;
1051                 } else
1052                         return 0;
1053         }
1054         /*
1055          * Read the data block if we don't already have it, give up if it fails.
1056          */
1057         if (!dbp) {
1058                 error = xfs_dir3_data_read(tp, dp, mp->m_dirdatablk, -1, &dbp);
1059                 if (error)
1060                         return error;
1061         }
1062         hdr = dbp->b_addr;
1063         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1064                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1065
1066         /*
1067          * Size of the "leaf" area in the block.
1068          */
1069         size = (uint)sizeof(xfs_dir2_block_tail_t) +
1070                (uint)sizeof(*lep) * (leafhdr.count - leafhdr.stale);
1071         /*
1072          * Look at the last data entry.
1073          */
1074         tagp = (__be16 *)((char *)hdr + mp->m_dirblksize) - 1;
1075         dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
1076         /*
1077          * If it's not free or is too short we can't do it.
1078          */
1079         if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG ||
1080             be16_to_cpu(dup->length) < size)
1081                 return 0;
1082
1083         /*
1084          * Start converting it to block form.
1085          */
1086         xfs_dir3_block_init(mp, tp, dbp, dp);
1087
1088         needlog = 1;
1089         needscan = 0;
1090         /*
1091          * Use up the space at the end of the block (blp/btp).
1092          */
1093         xfs_dir2_data_use_free(tp, dbp, dup, mp->m_dirblksize - size, size,
1094                 &needlog, &needscan);
1095         /*
1096          * Initialize the block tail.
1097          */
1098         btp = xfs_dir2_block_tail_p(mp, hdr);
1099         btp->count = cpu_to_be32(leafhdr.count - leafhdr.stale);
1100         btp->stale = 0;
1101         xfs_dir2_block_log_tail(tp, dbp);
1102         /*
1103          * Initialize the block leaf area.  We compact out stale entries.
1104          */
1105         lep = xfs_dir2_block_leaf_p(btp);
1106         for (from = to = 0; from < leafhdr.count; from++) {
1107                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
1108                         continue;
1109                 lep[to++] = ents[from];
1110         }
1111         ASSERT(to == be32_to_cpu(btp->count));
1112         xfs_dir2_block_log_leaf(tp, dbp, 0, be32_to_cpu(btp->count) - 1);
1113         /*
1114          * Scan the bestfree if we need it and log the data block header.
1115          */
1116         if (needscan)
1117                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1118         if (needlog)
1119                 xfs_dir2_data_log_header(tp, dbp);
1120         /*
1121          * Pitch the old leaf block.
1122          */
1123         error = xfs_da_shrink_inode(args, mp->m_dirleafblk, lbp);
1124         if (error)
1125                 return error;
1126
1127         /*
1128          * Now see if the resulting block can be shrunken to shortform.
1129          */
1130         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
1131         if (size > XFS_IFORK_DSIZE(dp))
1132                 return 0;
1133
1134         return xfs_dir2_block_to_sf(args, dbp, size, &sfh);
1135 }
1136
1137 /*
1138  * Convert the shortform directory to block form.
1139  */
1140 int                                             /* error */
1141 xfs_dir2_sf_to_block(
1142         xfs_da_args_t           *args)          /* operation arguments */
1143 {
1144         xfs_dir2_db_t           blkno;          /* dir-relative block # (0) */
1145         xfs_dir2_data_hdr_t     *hdr;           /* block header */
1146         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
1147         struct xfs_buf          *bp;            /* block buffer */
1148         xfs_dir2_block_tail_t   *btp;           /* block tail pointer */
1149         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1150         xfs_inode_t             *dp;            /* incore directory inode */
1151         int                     dummy;          /* trash */
1152         xfs_dir2_data_unused_t  *dup;           /* unused entry pointer */
1153         int                     endoffset;      /* end of data objects */
1154         int                     error;          /* error return value */
1155         int                     i;              /* index */
1156         xfs_mount_t             *mp;            /* filesystem mount point */
1157         int                     needlog;        /* need to log block header */
1158         int                     needscan;       /* need to scan block freespc */
1159         int                     newoffset;      /* offset from current entry */
1160         int                     offset;         /* target block offset */
1161         xfs_dir2_sf_entry_t     *sfep;          /* sf entry pointer */
1162         xfs_dir2_sf_hdr_t       *oldsfp;        /* old shortform header  */
1163         xfs_dir2_sf_hdr_t       *sfp;           /* shortform header  */
1164         __be16                  *tagp;          /* end of data entry */
1165         xfs_trans_t             *tp;            /* transaction pointer */
1166         struct xfs_name         name;
1167
1168         trace_xfs_dir2_sf_to_block(args);
1169
1170         dp = args->dp;
1171         tp = args->trans;
1172         mp = dp->i_mount;
1173         ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
1174         /*
1175          * Bomb out if the shortform directory is way too short.
1176          */
1177         if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
1178                 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1179                 return XFS_ERROR(EIO);
1180         }
1181
1182         oldsfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
1183
1184         ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
1185         ASSERT(dp->i_df.if_u1.if_data != NULL);
1186         ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(oldsfp->i8count));
1187
1188         /*
1189          * Copy the directory into a temporary buffer.
1190          * Then pitch the incore inode data so we can make extents.
1191          */
1192         sfp = kmem_alloc(dp->i_df.if_bytes, KM_SLEEP);
1193         memcpy(sfp, oldsfp, dp->i_df.if_bytes);
1194
1195         xfs_idata_realloc(dp, -dp->i_df.if_bytes, XFS_DATA_FORK);
1196         dp->i_d.di_size = 0;
1197         xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1198
1199         /*
1200          * Add block 0 to the inode.
1201          */
1202         error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE, &blkno);
1203         if (error) {
1204                 kmem_free(sfp);
1205                 return error;
1206         }
1207         /*
1208          * Initialize the data block, then convert it to block format.
1209          */
1210         error = xfs_dir3_data_init(args, blkno, &bp);
1211         if (error) {
1212                 kmem_free(sfp);
1213                 return error;
1214         }
1215         xfs_dir3_block_init(mp, tp, bp, dp);
1216         hdr = bp->b_addr;
1217
1218         /*
1219          * Compute size of block "tail" area.
1220          */
1221         i = (uint)sizeof(*btp) +
1222             (sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t);
1223         /*
1224          * The whole thing is initialized to free by the init routine.
1225          * Say we're using the leaf and tail area.
1226          */
1227         dup = xfs_dir3_data_unused_p(hdr);
1228         needlog = needscan = 0;
1229         xfs_dir2_data_use_free(tp, bp, dup, mp->m_dirblksize - i, i, &needlog,
1230                 &needscan);
1231         ASSERT(needscan == 0);
1232         /*
1233          * Fill in the tail.
1234          */
1235         btp = xfs_dir2_block_tail_p(mp, hdr);
1236         btp->count = cpu_to_be32(sfp->count + 2);       /* ., .. */
1237         btp->stale = 0;
1238         blp = xfs_dir2_block_leaf_p(btp);
1239         endoffset = (uint)((char *)blp - (char *)hdr);
1240         /*
1241          * Remove the freespace, we'll manage it.
1242          */
1243         xfs_dir2_data_use_free(tp, bp, dup,
1244                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
1245                 be16_to_cpu(dup->length), &needlog, &needscan);
1246         /*
1247          * Create entry for .
1248          */
1249         dep = xfs_dir3_data_dot_entry_p(hdr);
1250         dep->inumber = cpu_to_be64(dp->i_ino);
1251         dep->namelen = 1;
1252         dep->name[0] = '.';
1253         tagp = xfs_dir2_data_entry_tag_p(dep);
1254         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1255         xfs_dir2_data_log_entry(tp, bp, dep);
1256         blp[0].hashval = cpu_to_be32(xfs_dir_hash_dot);
1257         blp[0].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1258                                 (char *)dep - (char *)hdr));
1259         /*
1260          * Create entry for ..
1261          */
1262         dep = xfs_dir3_data_dotdot_entry_p(hdr);
1263         dep->inumber = cpu_to_be64(xfs_dir2_sf_get_parent_ino(sfp));
1264         dep->namelen = 2;
1265         dep->name[0] = dep->name[1] = '.';
1266         tagp = xfs_dir2_data_entry_tag_p(dep);
1267         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1268         xfs_dir2_data_log_entry(tp, bp, dep);
1269         blp[1].hashval = cpu_to_be32(xfs_dir_hash_dotdot);
1270         blp[1].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1271                                 (char *)dep - (char *)hdr));
1272         offset = xfs_dir3_data_first_offset(hdr);
1273         /*
1274          * Loop over existing entries, stuff them in.
1275          */
1276         i = 0;
1277         if (!sfp->count)
1278                 sfep = NULL;
1279         else
1280                 sfep = xfs_dir2_sf_firstentry(sfp);
1281         /*
1282          * Need to preserve the existing offset values in the sf directory.
1283          * Insert holes (unused entries) where necessary.
1284          */
1285         while (offset < endoffset) {
1286                 /*
1287                  * sfep is null when we reach the end of the list.
1288                  */
1289                 if (sfep == NULL)
1290                         newoffset = endoffset;
1291                 else
1292                         newoffset = xfs_dir2_sf_get_offset(sfep);
1293                 /*
1294                  * There should be a hole here, make one.
1295                  */
1296                 if (offset < newoffset) {
1297                         dup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
1298                         dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1299                         dup->length = cpu_to_be16(newoffset - offset);
1300                         *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16(
1301                                 ((char *)dup - (char *)hdr));
1302                         xfs_dir2_data_log_unused(tp, bp, dup);
1303                         xfs_dir2_data_freeinsert(hdr, dup, &dummy);
1304                         offset += be16_to_cpu(dup->length);
1305                         continue;
1306                 }
1307                 /*
1308                  * Copy a real entry.
1309                  */
1310                 dep = (xfs_dir2_data_entry_t *)((char *)hdr + newoffset);
1311                 dep->inumber = cpu_to_be64(xfs_dir2_sfe_get_ino(sfp, sfep));
1312                 dep->namelen = sfep->namelen;
1313                 memcpy(dep->name, sfep->name, dep->namelen);
1314                 tagp = xfs_dir2_data_entry_tag_p(dep);
1315                 *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1316                 xfs_dir2_data_log_entry(tp, bp, dep);
1317                 name.name = sfep->name;
1318                 name.len = sfep->namelen;
1319                 blp[2 + i].hashval = cpu_to_be32(mp->m_dirnameops->
1320                                                         hashname(&name));
1321                 blp[2 + i].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(mp,
1322                                                  (char *)dep - (char *)hdr));
1323                 offset = (int)((char *)(tagp + 1) - (char *)hdr);
1324                 if (++i == sfp->count)
1325                         sfep = NULL;
1326                 else
1327                         sfep = xfs_dir2_sf_nextentry(sfp, sfep);
1328         }
1329         /* Done with the temporary buffer */
1330         kmem_free(sfp);
1331         /*
1332          * Sort the leaf entries by hash value.
1333          */
1334         xfs_sort(blp, be32_to_cpu(btp->count), sizeof(*blp), xfs_dir2_block_sort);
1335         /*
1336          * Log the leaf entry area and tail.
1337          * Already logged the header in data_init, ignore needlog.
1338          */
1339         ASSERT(needscan == 0);
1340         xfs_dir2_block_log_leaf(tp, bp, 0, be32_to_cpu(btp->count) - 1);
1341         xfs_dir2_block_log_tail(tp, bp);
1342         xfs_dir3_data_check(dp, bp);
1343         return 0;
1344 }