fs/xfs/xfs_dir2_leaf.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_bit.h"
  22 #include "xfs_log.h"
  23 #include "xfs_inum.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_mount.h"
  28 #include "xfs_da_btree.h"
  29 #include "xfs_bmap_btree.h"
  30 #include "xfs_dinode.h"
  31 #include "xfs_inode.h"
  32 #include "xfs_bmap.h"
  33 #include "xfs_dir2_format.h"
  34 #include "xfs_dir2_priv.h"
  35 #include "xfs_error.h"
  36 #include "xfs_trace.h"
  37
  38 /*
  39  * Local function declarations.
  40  */
  41 #ifdef DEBUG
  42 static void xfs_dir2_leaf_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
  43 #else
  44 #define xfs_dir2_leaf_check(dp, bp)
  45 #endif
  46 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **lbpp,
  47                                     int *indexp, xfs_dabuf_t **dbpp);
  48 static void xfs_dir2_leaf_log_bests(struct xfs_trans *tp, struct xfs_dabuf *bp,
  49                                     int first, int last);
  50 static void xfs_dir2_leaf_log_tail(struct xfs_trans *tp, struct xfs_dabuf *bp);
  51
  52
  53 /*
  54  * Convert a block form directory to a leaf form directory.
  55  */
  56 int                                             /* error */
  57 xfs_dir2_block_to_leaf(
  58         xfs_da_args_t           *args,          /* operation arguments */
  59         xfs_dabuf_t             *dbp)           /* input block's buffer */
  60 {
  61         __be16                  *bestsp;        /* leaf's bestsp entries */
  62         xfs_dablk_t             blkno;          /* leaf block's bno */
  63         xfs_dir2_data_hdr_t     *hdr;           /* block header */
  64         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
  65         xfs_dir2_block_tail_t   *btp;           /* block's tail */
  66         xfs_inode_t             *dp;            /* incore directory inode */
  67         int                     error;          /* error return code */
  68         xfs_dabuf_t             *lbp;           /* leaf block's buffer */
  69         xfs_dir2_db_t           ldb;            /* leaf block's bno */
  70         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
  71         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
  72         xfs_mount_t             *mp;            /* filesystem mount point */
  73         int                     needlog;        /* need to log block header */
  74         int                     needscan;       /* need to rescan bestfree */
  75         xfs_trans_t             *tp;            /* transaction pointer */
  76
  77         trace_xfs_dir2_block_to_leaf(args);
  78
  79         dp = args->dp;
  80         mp = dp->i_mount;
  81         tp = args->trans;
  82         /*
  83          * Add the leaf block to the inode.
  84          * This interface will only put blocks in the leaf/node range.
  85          * Since that's empty now, we'll get the root (block 0 in range).
  86          */
  87         if ((error = xfs_da_grow_inode(args, &blkno))) {
  88                 return error;
  89         }
  90         ldb = xfs_dir2_da_to_db(mp, blkno);
  91         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
  92         /*
  93          * Initialize the leaf block, get a buffer for it.
  94          */
  95         if ((error = xfs_dir2_leaf_init(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC))) {
  96                 return error;
  97         }
  98         ASSERT(lbp != NULL);
  99         leaf = lbp->data;
 100         hdr = dbp->data;
 101         xfs_dir2_data_check(dp, dbp);
 102         btp = xfs_dir2_block_tail_p(mp, hdr);
 103         blp = xfs_dir2_block_leaf_p(btp);
 104         /*
 105          * Set the counts in the leaf header.
 106          */
 107         leaf->hdr.count = cpu_to_be16(be32_to_cpu(btp->count));
 108         leaf->hdr.stale = cpu_to_be16(be32_to_cpu(btp->stale));
 109         /*
 110          * Could compact these but I think we always do the conversion
 111          * after squeezing out stale entries.
 112          */
 113         memcpy(leaf->ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
 114         xfs_dir2_leaf_log_ents(tp, lbp, 0, be16_to_cpu(leaf->hdr.count) - 1);
 115         needscan = 0;
 116         needlog = 1;
 117         /*
 118          * Make the space formerly occupied by the leaf entries and block
 119          * tail be free.
 120          */
 121         xfs_dir2_data_make_free(tp, dbp,
 122                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 123                 (xfs_dir2_data_aoff_t)((char *)hdr + mp->m_dirblksize -
 124                                        (char *)blp),
 125                 &needlog, &needscan);
 126         /*
 127          * Fix up the block header, make it a data block.
 128          */
 129         hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 130         if (needscan)
 131                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 132         /*
 133          * Set up leaf tail and bests table.
 134          */
 135         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 136         ltp->bestcount = cpu_to_be32(1);
 137         bestsp = xfs_dir2_leaf_bests_p(ltp);
 138         bestsp[0] =  hdr->bestfree[0].length;
 139         /*
 140          * Log the data header and leaf bests table.
 141          */
 142         if (needlog)
 143                 xfs_dir2_data_log_header(tp, dbp);
 144         xfs_dir2_leaf_check(dp, lbp);
 145         xfs_dir2_data_check(dp, dbp);
 146         xfs_dir2_leaf_log_bests(tp, lbp, 0, 0);
 147         xfs_da_buf_done(lbp);
 148         return 0;
 149 }
 150
 151 STATIC void
 152 xfs_dir2_leaf_find_stale(
 153         struct xfs_dir2_leaf    *leaf,
 154         int                     index,
 155         int                     *lowstale,
 156         int                     *highstale)
 157 {
 158         /*
 159          * Find the first stale entry before our index, if any.
 160          */
 161         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 162                 if (leaf->ents[*lowstale].address ==
 163                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 164                         break;
 165         }
 166
 167         /*
 168          * Find the first stale entry at or after our index, if any.
 169          * Stop if the result would require moving more entries than using
 170          * lowstale.
 171          */
 172         for (*highstale = index;
 173              *highstale < be16_to_cpu(leaf->hdr.count);
 174              ++*highstale) {
 175                 if (leaf->ents[*highstale].address ==
 176                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 177                         break;
 178                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 179                         break;
 180         }
 181 }
 182
 183 struct xfs_dir2_leaf_entry *
 184 xfs_dir2_leaf_find_entry(
 185         xfs_dir2_leaf_t         *leaf,          /* leaf structure */
 186         int                     index,          /* leaf table position */
 187         int                     compact,        /* need to compact leaves */
 188         int                     lowstale,       /* index of prev stale leaf */
 189         int                     highstale,      /* index of next stale leaf */
 190         int                     *lfloglow,      /* low leaf logging index */
 191         int                     *lfloghigh)     /* high leaf logging index */
 192 {
 193         if (!leaf->hdr.stale) {
 194                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 195
 196                 /*
 197                  * Now we need to make room to insert the leaf entry.
 198                  *
 199                  * If there are no stale entries, just insert a hole at index.
 200                  */
 201                 lep = &leaf->ents[index];
 202                 if (index < be16_to_cpu(leaf->hdr.count))
 203                         memmove(lep + 1, lep,
 204                                 (be16_to_cpu(leaf->hdr.count) - index) *
 205                                  sizeof(*lep));
 206
 207                 /*
 208                  * Record low and high logging indices for the leaf.
 209                  */
 210                 *lfloglow = index;
 211                 *lfloghigh = be16_to_cpu(leaf->hdr.count);
 212                 be16_add_cpu(&leaf->hdr.count, 1);
 213                 return lep;
 214         }
 215
 216         /*
 217          * There are stale entries.
 218          *
 219          * We will use one of them for the new entry.  It's probably not at
 220          * the right location, so we'll have to shift some up or down first.
 221          *
 222          * If we didn't compact before, we need to find the nearest stale
 223          * entries before and after our insertion point.
 224          */
 225         if (compact == 0)
 226                 xfs_dir2_leaf_find_stale(leaf, index, &lowstale, &highstale);
 227
 228         /*
 229          * If the low one is better, use it.
 230          */
 231         if (lowstale >= 0 &&
 232             (highstale == be16_to_cpu(leaf->hdr.count) ||
 233              index - lowstale - 1 < highstale - index)) {
 234                 ASSERT(index - lowstale - 1 >= 0);
 235                 ASSERT(leaf->ents[lowstale].address ==
 236                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 237
 238                 /*
 239                  * Copy entries up to cover the stale entry and make room
 240                  * for the new entry.
 241                  */
 242                 if (index - lowstale - 1 > 0) {
 243                         memmove(&leaf->ents[lowstale],
 244                                 &leaf->ents[lowstale + 1],
 245                                 (index - lowstale - 1) *
 246                                 sizeof(xfs_dir2_leaf_entry_t));
 247                 }
 248                 *lfloglow = MIN(lowstale, *lfloglow);
 249                 *lfloghigh = MAX(index - 1, *lfloghigh);
 250                 be16_add_cpu(&leaf->hdr.stale, -1);
 251                 return &leaf->ents[index - 1];
 252         }
 253
 254         /*
 255          * The high one is better, so use that one.
 256          */
 257         ASSERT(highstale - index >= 0);
 258         ASSERT(leaf->ents[highstale].address ==
 259                cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 260
 261         /*
 262          * Copy entries down to cover the stale entry and make room for the
 263          * new entry.
 264          */
 265         if (highstale - index > 0) {
 266                 memmove(&leaf->ents[index + 1],
 267                         &leaf->ents[index],
 268                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 269         }
 270         *lfloglow = MIN(index, *lfloglow);
 271         *lfloghigh = MAX(highstale, *lfloghigh);
 272         be16_add_cpu(&leaf->hdr.stale, -1);
 273         return &leaf->ents[index];
 274 }
 275
 276 /*
 277  * Add an entry to a leaf form directory.
 278  */
 279 int                                             /* error */
 280 xfs_dir2_leaf_addname(
 281         xfs_da_args_t           *args)          /* operation arguments */
 282 {
 283         __be16                  *bestsp;        /* freespace table in leaf */
 284         int                     compact;        /* need to compact leaves */
 285         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 286         xfs_dabuf_t             *dbp;           /* data block buffer */
 287         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 288         xfs_inode_t             *dp;            /* incore directory inode */
 289         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 290         int                     error;          /* error return value */
 291         int                     grown;          /* allocated new data block */
 292         int                     highstale;      /* index of next stale leaf */
 293         int                     i;              /* temporary, index */
 294         int                     index;          /* leaf table position */
 295         xfs_dabuf_t             *lbp;           /* leaf's buffer */
 296         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 297         int                     length;         /* length of new entry */
 298         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 299         int                     lfloglow;       /* low leaf logging index */
 300         int                     lfloghigh;      /* high leaf logging index */
 301         int                     lowstale;       /* index of prev stale leaf */
 302         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 303         xfs_mount_t             *mp;            /* filesystem mount point */
 304         int                     needbytes;      /* leaf block bytes needed */
 305         int                     needlog;        /* need to log data header */
 306         int                     needscan;       /* need to rescan data free */
 307         __be16                  *tagp;          /* end of data entry */
 308         xfs_trans_t             *tp;            /* transaction pointer */
 309         xfs_dir2_db_t           use_block;      /* data block number */
 310
 311         trace_xfs_dir2_leaf_addname(args);
 312
 313         dp = args->dp;
 314         tp = args->trans;
 315         mp = dp->i_mount;
 316         /*
 317          * Read the leaf block.
 318          */
 319         error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
 320                 XFS_DATA_FORK);
 321         if (error) {
 322                 return error;
 323         }
 324         ASSERT(lbp != NULL);
 325         /*
 326          * Look up the entry by hash value and name.
 327          * We know it's not there, our caller has already done a lookup.
 328          * So the index is of the entry to insert in front of.
 329          * But if there are dup hash values the index is of the first of those.
 330          */
 331         index = xfs_dir2_leaf_search_hash(args, lbp);
 332         leaf = lbp->data;
 333         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 334         bestsp = xfs_dir2_leaf_bests_p(ltp);
 335         length = xfs_dir2_data_entsize(args->namelen);
 336         /*
 337          * See if there are any entries with the same hash value
 338          * and space in their block for the new entry.
 339          * This is good because it puts multiple same-hash value entries
 340          * in a data block, improving the lookup of those entries.
 341          */
 342         for (use_block = -1, lep = &leaf->ents[index];
 343              index < be16_to_cpu(leaf->hdr.count) && be32_to_cpu(lep->hashval) == args->hashval;
 344              index++, lep++) {
 345                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 346                         continue;
 347                 i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 348                 ASSERT(i < be32_to_cpu(ltp->bestcount));
 349                 ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 350                 if (be16_to_cpu(bestsp[i]) >= length) {
 351                         use_block = i;
 352                         break;
 353                 }
 354         }
 355         /*
 356          * Didn't find a block yet, linear search all the data blocks.
 357          */
 358         if (use_block == -1) {
 359                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 360                         /*
 361                          * Remember a block we see that's missing.
 362                          */
 363                         if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 364                             use_block == -1)
 365                                 use_block = i;
 366                         else if (be16_to_cpu(bestsp[i]) >= length) {
 367                                 use_block = i;
 368                                 break;
 369                         }
 370                 }
 371         }
 372         /*
 373          * How many bytes do we need in the leaf block?
 374          */
 375         needbytes = 0;
 376         if (!leaf->hdr.stale)
 377                 needbytes += sizeof(xfs_dir2_leaf_entry_t);
 378         if (use_block == -1)
 379                 needbytes += sizeof(xfs_dir2_data_off_t);
 380
 381         /*
 382          * Now kill use_block if it refers to a missing block, so we
 383          * can use it as an indication of allocation needed.
 384          */
 385         if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 386                 use_block = -1;
 387         /*
 388          * If we don't have enough free bytes but we can make enough
 389          * by compacting out stale entries, we'll do that.
 390          */
 391         if ((char *)bestsp - (char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] <
 392                                 needbytes && be16_to_cpu(leaf->hdr.stale) > 1) {
 393                 compact = 1;
 394         }
 395         /*
 396          * Otherwise if we don't have enough free bytes we need to
 397          * convert to node form.
 398          */
 399         else if ((char *)bestsp - (char *)&leaf->ents[be16_to_cpu(
 400                                                 leaf->hdr.count)] < needbytes) {
 401                 /*
 402                  * Just checking or no space reservation, give up.
 403                  */
 404                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 405                                                         args->total == 0) {
 406                         xfs_da_brelse(tp, lbp);
 407                         return XFS_ERROR(ENOSPC);
 408                 }
 409                 /*
 410                  * Convert to node form.
 411                  */
 412                 error = xfs_dir2_leaf_to_node(args, lbp);
 413                 xfs_da_buf_done(lbp);
 414                 if (error)
 415                         return error;
 416                 /*
 417                  * Then add the new entry.
 418                  */
 419                 return xfs_dir2_node_addname(args);
 420         }
 421         /*
 422          * Otherwise it will fit without compaction.
 423          */
 424         else
 425                 compact = 0;
 426         /*
 427          * If just checking, then it will fit unless we needed to allocate
 428          * a new data block.
 429          */
 430         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 431                 xfs_da_brelse(tp, lbp);
 432                 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
 433         }
 434         /*
 435          * If no allocations are allowed, return now before we've
 436          * changed anything.
 437          */
 438         if (args->total == 0 && use_block == -1) {
 439                 xfs_da_brelse(tp, lbp);
 440                 return XFS_ERROR(ENOSPC);
 441         }
 442         /*
 443          * Need to compact the leaf entries, removing stale ones.
 444          * Leave one stale entry behind - the one closest to our
 445          * insertion index - and we'll shift that one to our insertion
 446          * point later.
 447          */
 448         if (compact) {
 449                 xfs_dir2_leaf_compact_x1(lbp, &index, &lowstale, &highstale,
 450                         &lfloglow, &lfloghigh);
 451         }
 452         /*
 453          * There are stale entries, so we'll need log-low and log-high
 454          * impossibly bad values later.
 455          */
 456         else if (be16_to_cpu(leaf->hdr.stale)) {
 457                 lfloglow = be16_to_cpu(leaf->hdr.count);
 458                 lfloghigh = -1;
 459         }
 460         /*
 461          * If there was no data block space found, we need to allocate
 462          * a new one.
 463          */
 464         if (use_block == -1) {
 465                 /*
 466                  * Add the new data block.
 467                  */
 468                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 469                                 &use_block))) {
 470                         xfs_da_brelse(tp, lbp);
 471                         return error;
 472                 }
 473                 /*
 474                  * Initialize the block.
 475                  */
 476                 if ((error = xfs_dir2_data_init(args, use_block, &dbp))) {
 477                         xfs_da_brelse(tp, lbp);
 478                         return error;
 479                 }
 480                 /*
 481                  * If we're adding a new data block on the end we need to
 482                  * extend the bests table.  Copy it up one entry.
 483                  */
 484                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
 485                         bestsp--;
 486                         memmove(&bestsp[0], &bestsp[1],
 487                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 488                         be32_add_cpu(&ltp->bestcount, 1);
 489                         xfs_dir2_leaf_log_tail(tp, lbp);
 490                         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
 491                 }
 492                 /*
 493                  * If we're filling in a previously empty block just log it.
 494                  */
 495                 else
 496                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
 497                 hdr = dbp->data;
 498                 bestsp[use_block] = hdr->bestfree[0].length;
 499                 grown = 1;
 500         }
 501         /*
 502          * Already had space in some data block.
 503          * Just read that one in.
 504          */
 505         else {
 506                 if ((error =
 507                     xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, use_block),
 508                             -1, &dbp, XFS_DATA_FORK))) {
 509                         xfs_da_brelse(tp, lbp);
 510                         return error;
 511                 }
 512                 hdr = dbp->data;
 513                 grown = 0;
 514         }
 515         xfs_dir2_data_check(dp, dbp);
 516         /*
 517          * Point to the biggest freespace in our data block.
 518          */
 519         dup = (xfs_dir2_data_unused_t *)
 520               ((char *)hdr + be16_to_cpu(hdr->bestfree[0].offset));
 521         ASSERT(be16_to_cpu(dup->length) >= length);
 522         needscan = needlog = 0;
 523         /*
 524          * Mark the initial part of our freespace in use for the new entry.
 525          */
 526         xfs_dir2_data_use_free(tp, dbp, dup,
 527                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
 528                 &needlog, &needscan);
 529         /*
 530          * Initialize our new entry (at last).
 531          */
 532         dep = (xfs_dir2_data_entry_t *)dup;
 533         dep->inumber = cpu_to_be64(args->inumber);
 534         dep->namelen = args->namelen;
 535         memcpy(dep->name, args->name, dep->namelen);
 536         tagp = xfs_dir2_data_entry_tag_p(dep);
 537         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 538         /*
 539          * Need to scan fix up the bestfree table.
 540          */
 541         if (needscan)
 542                 xfs_dir2_data_freescan(mp, hdr, &needlog);
 543         /*
 544          * Need to log the data block's header.
 545          */
 546         if (needlog)
 547                 xfs_dir2_data_log_header(tp, dbp);
 548         xfs_dir2_data_log_entry(tp, dbp, dep);
 549         /*
 550          * If the bests table needs to be changed, do it.
 551          * Log the change unless we've already done that.
 552          */
 553         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(hdr->bestfree[0].length)) {
 554                 bestsp[use_block] = hdr->bestfree[0].length;
 555                 if (!grown)
 556                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
 557         }
 558
 559         lep = xfs_dir2_leaf_find_entry(leaf, index, compact, lowstale,
 560                                        highstale, &lfloglow, &lfloghigh);
 561
 562         /*
 563          * Fill in the new leaf entry.
 564          */
 565         lep->hashval = cpu_to_be32(args->hashval);
 566         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
 567                                 be16_to_cpu(*tagp)));
 568         /*
 569          * Log the leaf fields and give up the buffers.
 570          */
 571         xfs_dir2_leaf_log_header(tp, lbp);
 572         xfs_dir2_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
 573         xfs_dir2_leaf_check(dp, lbp);
 574         xfs_da_buf_done(lbp);
 575         xfs_dir2_data_check(dp, dbp);
 576         xfs_da_buf_done(dbp);
 577         return 0;
 578 }
 579
 580 #ifdef DEBUG
 581 /*
 582  * Check the internal consistency of a leaf1 block.
 583  * Pop an assert if something is wrong.
 584  */
 585 STATIC void
 586 xfs_dir2_leaf_check(
 587         xfs_inode_t             *dp,            /* incore directory inode */
 588         xfs_dabuf_t             *bp)            /* leaf's buffer */
 589 {
 590         int                     i;              /* leaf index */
 591         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 592         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 593         xfs_mount_t             *mp;            /* filesystem mount point */
 594         int                     stale;          /* count of stale leaves */
 595
 596         leaf = bp->data;
 597         mp = dp->i_mount;
 598         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
 599         /*
 600          * This value is not restrictive enough.
 601          * Should factor in the size of the bests table as well.
 602          * We can deduce a value for that from di_size.
 603          */
 604         ASSERT(be16_to_cpu(leaf->hdr.count) <= xfs_dir2_max_leaf_ents(mp));
 605         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 606         /*
 607          * Leaves and bests don't overlap.
 608          */
 609         ASSERT((char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] <=
 610                (char *)xfs_dir2_leaf_bests_p(ltp));
 611         /*
 612          * Check hash value order, count stale entries.
 613          */
 614         for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
 615                 if (i + 1 < be16_to_cpu(leaf->hdr.count))
 616                         ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
 617                                be32_to_cpu(leaf->ents[i + 1].hashval));
 618                 if (leaf->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 619                         stale++;
 620         }
 621         ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
 622 }
 623 #endif  /* DEBUG */
 624
 625 /*
 626  * Compact out any stale entries in the leaf.
 627  * Log the header and changed leaf entries, if any.
 628  */
 629 void
 630 xfs_dir2_leaf_compact(
 631         xfs_da_args_t   *args,          /* operation arguments */
 632         xfs_dabuf_t     *bp)            /* leaf buffer */
 633 {
 634         int             from;           /* source leaf index */
 635         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 636         int             loglow;         /* first leaf entry to log */
 637         int             to;             /* target leaf index */
 638
 639         leaf = bp->data;
 640         if (!leaf->hdr.stale) {
 641                 return;
 642         }
 643         /*
 644          * Compress out the stale entries in place.
 645          */
 646         for (from = to = 0, loglow = -1; from < be16_to_cpu(leaf->hdr.count); from++) {
 647                 if (leaf->ents[from].address ==
 648                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 649                         continue;
 650                 /*
 651                  * Only actually copy the entries that are different.
 652                  */
 653                 if (from > to) {
 654                         if (loglow == -1)
 655                                 loglow = to;
 656                         leaf->ents[to] = leaf->ents[from];
 657                 }
 658                 to++;
 659         }
 660         /*
 661          * Update and log the header, log the leaf entries.
 662          */
 663         ASSERT(be16_to_cpu(leaf->hdr.stale) == from - to);
 664         be16_add_cpu(&leaf->hdr.count, -(be16_to_cpu(leaf->hdr.stale)));
 665         leaf->hdr.stale = 0;
 666         xfs_dir2_leaf_log_header(args->trans, bp);
 667         if (loglow != -1)
 668                 xfs_dir2_leaf_log_ents(args->trans, bp, loglow, to - 1);
 669 }
 670
 671 /*
 672  * Compact the leaf entries, removing stale ones.
 673  * Leave one stale entry behind - the one closest to our
 674  * insertion index - and the caller will shift that one to our insertion
 675  * point later.
 676  * Return new insertion index, where the remaining stale entry is,
 677  * and leaf logging indices.
 678  */
 679 void
 680 xfs_dir2_leaf_compact_x1(
 681         xfs_dabuf_t     *bp,            /* leaf buffer */
 682         int             *indexp,        /* insertion index */
 683         int             *lowstalep,     /* out: stale entry before us */
 684         int             *highstalep,    /* out: stale entry after us */
 685         int             *lowlogp,       /* out: low log index */
 686         int             *highlogp)      /* out: high log index */
 687 {
 688         int             from;           /* source copy index */
 689         int             highstale;      /* stale entry at/after index */
 690         int             index;          /* insertion index */
 691         int             keepstale;      /* source index of kept stale */
 692         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 693         int             lowstale;       /* stale entry before index */
 694         int             newindex=0;     /* new insertion index */
 695         int             to;             /* destination copy index */
 696
 697         leaf = bp->data;
 698         ASSERT(be16_to_cpu(leaf->hdr.stale) > 1);
 699         index = *indexp;
 700
 701         xfs_dir2_leaf_find_stale(leaf, index, &lowstale, &highstale);
 702
 703         /*
 704          * Pick the better of lowstale and highstale.
 705          */
 706         if (lowstale >= 0 &&
 707             (highstale == be16_to_cpu(leaf->hdr.count) ||
 708              index - lowstale <= highstale - index))
 709                 keepstale = lowstale;
 710         else
 711                 keepstale = highstale;
 712         /*
 713          * Copy the entries in place, removing all the stale entries
 714          * except keepstale.
 715          */
 716         for (from = to = 0; from < be16_to_cpu(leaf->hdr.count); from++) {
 717                 /*
 718                  * Notice the new value of index.
 719                  */
 720                 if (index == from)
 721                         newindex = to;
 722                 if (from != keepstale &&
 723                     leaf->ents[from].address ==
 724                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
 725                         if (from == to)
 726                                 *lowlogp = to;
 727                         continue;
 728                 }
 729                 /*
 730                  * Record the new keepstale value for the insertion.
 731                  */
 732                 if (from == keepstale)
 733                         lowstale = highstale = to;
 734                 /*
 735                  * Copy only the entries that have moved.
 736                  */
 737                 if (from > to)
 738                         leaf->ents[to] = leaf->ents[from];
 739                 to++;
 740         }
 741         ASSERT(from > to);
 742         /*
 743          * If the insertion point was past the last entry,
 744          * set the new insertion point accordingly.
 745          */
 746         if (index == from)
 747                 newindex = to;
 748         *indexp = newindex;
 749         /*
 750          * Adjust the leaf header values.
 751          */
 752         be16_add_cpu(&leaf->hdr.count, -(from - to));
 753         leaf->hdr.stale = cpu_to_be16(1);
 754         /*
 755          * Remember the low/high stale value only in the "right"
 756          * direction.
 757          */
 758         if (lowstale >= newindex)
 759                 lowstale = -1;
 760         else
 761                 highstale = be16_to_cpu(leaf->hdr.count);
 762         *highlogp = be16_to_cpu(leaf->hdr.count) - 1;
 763         *lowstalep = lowstale;
 764         *highstalep = highstale;
 765 }
 766
 767 /*
 768  * Getdents (readdir) for leaf and node directories.
 769  * This reads the data blocks only, so is the same for both forms.
 770  */
 771 int                                             /* error */
 772 xfs_dir2_leaf_getdents(
 773         xfs_inode_t             *dp,            /* incore directory inode */
 774         void                    *dirent,
 775         size_t                  bufsize,
 776         xfs_off_t               *offset,
 777         filldir_t               filldir)
 778 {
 779         xfs_dabuf_t             *bp;            /* data block buffer */
 780         int                     byteoff;        /* offset in current block */
 781         xfs_dir2_db_t           curdb;          /* db for current block */
 782         xfs_dir2_off_t          curoff;         /* current overall offset */
 783         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 784         xfs_dir2_data_entry_t   *dep;           /* data entry */
 785         xfs_dir2_data_unused_t  *dup;           /* unused entry */
 786         int                     error = 0;      /* error return value */
 787         int                     i;              /* temporary loop index */
 788         int                     j;              /* temporary loop index */
 789         int                     length;         /* temporary length value */
 790         xfs_bmbt_irec_t         *map;           /* map vector for blocks */
 791         xfs_extlen_t            map_blocks;     /* number of fsbs in map */
 792         xfs_dablk_t             map_off;        /* last mapped file offset */
 793         int                     map_size;       /* total entries in *map */
 794         int                     map_valid;      /* valid entries in *map */
 795         xfs_mount_t             *mp;            /* filesystem mount point */
 796         xfs_dir2_off_t          newoff;         /* new curoff after new blk */
 797         int                     nmap;           /* mappings to ask xfs_bmapi */
 798         char                    *ptr = NULL;    /* pointer to current data */
 799         int                     ra_current;     /* number of read-ahead blks */
 800         int                     ra_index;       /* *map index for read-ahead */
 801         int                     ra_offset;      /* map entry offset for ra */
 802         int                     ra_want;        /* readahead count wanted */
 803
 804         /*
 805          * If the offset is at or past the largest allowed value,
 806          * give up right away.
 807          */
 808         if (*offset >= XFS_DIR2_MAX_DATAPTR)
 809                 return 0;
 810
 811         mp = dp->i_mount;
 812
 813         /*
 814          * Set up to bmap a number of blocks based on the caller's
 815          * buffer size, the directory block size, and the filesystem
 816          * block size.
 817          */
 818         map_size = howmany(bufsize + mp->m_dirblksize, mp->m_sb.sb_blocksize);
 819         map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
 820         map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
 821         bp = NULL;
 822
 823         /*
 824          * Inside the loop we keep the main offset value as a byte offset
 825          * in the directory file.
 826          */
 827         curoff = xfs_dir2_dataptr_to_byte(mp, *offset);
 828
 829         /*
 830          * Force this conversion through db so we truncate the offset
 831          * down to get the start of the data block.
 832          */
 833         map_off = xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, curoff));
 834         /*
 835          * Loop over directory entries until we reach the end offset.
 836          * Get more blocks and readahead as necessary.
 837          */
 838         while (curoff < XFS_DIR2_LEAF_OFFSET) {
 839                 /*
 840                  * If we have no buffer, or we're off the end of the
 841                  * current buffer, need to get another one.
 842                  */
 843                 if (!bp || ptr >= (char *)bp->data + mp->m_dirblksize) {
 844                         /*
 845                          * If we have a buffer, we need to release it and
 846                          * take it out of the mapping.
 847                          */
 848                         if (bp) {
 849                                 xfs_da_brelse(NULL, bp);
 850                                 bp = NULL;
 851                                 map_blocks -= mp->m_dirblkfsbs;
 852                                 /*
 853                                  * Loop to get rid of the extents for the
 854                                  * directory block.
 855                                  */
 856                                 for (i = mp->m_dirblkfsbs; i > 0; ) {
 857                                         j = MIN((int)map->br_blockcount, i);
 858                                         map->br_blockcount -= j;
 859                                         map->br_startblock += j;
 860                                         map->br_startoff += j;
 861                                         /*
 862                                          * If mapping is done, pitch it from
 863                                          * the table.
 864                                          */
 865                                         if (!map->br_blockcount && --map_valid)
 866                                                 memmove(&map[0], &map[1],
 867                                                         sizeof(map[0]) *
 868                                                         map_valid);
 869                                         i -= j;
 870                                 }
 871                         }
 872                         /*
 873                          * Recalculate the readahead blocks wanted.
 874                          */
 875                         ra_want = howmany(bufsize + mp->m_dirblksize,
 876                                           mp->m_sb.sb_blocksize) - 1;
 877                         ASSERT(ra_want >= 0);
 878
 879                         /*
 880                          * If we don't have as many as we want, and we haven't
 881                          * run out of data blocks, get some more mappings.
 882                          */
 883                         if (1 + ra_want > map_blocks &&
 884                             map_off <
 885                             xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
 886                                 /*
 887                                  * Get more bmaps, fill in after the ones
 888                                  * we already have in the table.
 889                                  */
 890                                 nmap = map_size - map_valid;
 891                                 error = xfs_bmapi(NULL, dp,
 892                                         map_off,
 893                                         xfs_dir2_byte_to_da(mp,
 894                                                 XFS_DIR2_LEAF_OFFSET) - map_off,
 895                                         XFS_BMAPI_METADATA, NULL, 0,
 896                                         &map[map_valid], &nmap, NULL);
 897                                 /*
 898                                  * Don't know if we should ignore this or
 899                                  * try to return an error.
 900                                  * The trouble with returning errors
 901                                  * is that readdir will just stop without
 902                                  * actually passing the error through.
 903                                  */
 904                                 if (error)
 905                                         break;  /* XXX */
 906                                 /*
 907                                  * If we got all the mappings we asked for,
 908                                  * set the final map offset based on the
 909                                  * last bmap value received.
 910                                  * Otherwise, we've reached the end.
 911                                  */
 912                                 if (nmap == map_size - map_valid)
 913                                         map_off =
 914                                         map[map_valid + nmap - 1].br_startoff +
 915                                         map[map_valid + nmap - 1].br_blockcount;
 916                                 else
 917                                         map_off =
 918                                                 xfs_dir2_byte_to_da(mp,
 919                                                         XFS_DIR2_LEAF_OFFSET);
 920                                 /*
 921                                  * Look for holes in the mapping, and
 922                                  * eliminate them.  Count up the valid blocks.
 923                                  */
 924                                 for (i = map_valid; i < map_valid + nmap; ) {
 925                                         if (map[i].br_startblock ==
 926                                             HOLESTARTBLOCK) {
 927                                                 nmap--;
 928                                                 length = map_valid + nmap - i;
 929                                                 if (length)
 930                                                         memmove(&map[i],
 931                                                                 &map[i + 1],
 932                                                                 sizeof(map[i]) *
 933                                                                 length);
 934                                         } else {
 935                                                 map_blocks +=
 936                                                         map[i].br_blockcount;
 937                                                 i++;
 938                                         }
 939                                 }
 940                                 map_valid += nmap;
 941                         }
 942                         /*
 943                          * No valid mappings, so no more data blocks.
 944                          */
 945                         if (!map_valid) {
 946                                 curoff = xfs_dir2_da_to_byte(mp, map_off);
 947                                 break;
 948                         }
 949                         /*
 950                          * Read the directory block starting at the first
 951                          * mapping.
 952                          */
 953                         curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
 954                         error = xfs_da_read_buf(NULL, dp, map->br_startoff,
 955                                 map->br_blockcount >= mp->m_dirblkfsbs ?
 956                                     XFS_FSB_TO_DADDR(mp, map->br_startblock) :
 957                                     -1,
 958                                 &bp, XFS_DATA_FORK);
 959                         /*
 960                          * Should just skip over the data block instead
 961                          * of giving up.
 962                          */
 963                         if (error)
 964                                 break;  /* XXX */
 965                         /*
 966                          * Adjust the current amount of read-ahead: we just
 967                          * read a block that was previously ra.
 968                          */
 969                         if (ra_current)
 970                                 ra_current -= mp->m_dirblkfsbs;
 971                         /*
 972                          * Do we need more readahead?
 973                          */
 974                         for (ra_index = ra_offset = i = 0;
 975                              ra_want > ra_current && i < map_blocks;
 976                              i += mp->m_dirblkfsbs) {
 977                                 ASSERT(ra_index < map_valid);
 978                                 /*
 979                                  * Read-ahead a contiguous directory block.
 980                                  */
 981                                 if (i > ra_current &&
 982                                     map[ra_index].br_blockcount >=
 983                                     mp->m_dirblkfsbs) {
 984                                         xfs_buf_readahead(mp->m_ddev_targp,
 985                                                 XFS_FSB_TO_DADDR(mp,
 986                                                    map[ra_index].br_startblock +
 987                                                    ra_offset),
 988                                                 (int)BTOBB(mp->m_dirblksize));
 989                                         ra_current = i;
 990                                 }
 991                                 /*
 992                                  * Read-ahead a non-contiguous directory block.
 993                                  * This doesn't use our mapping, but this
 994                                  * is a very rare case.
 995                                  */
 996                                 else if (i > ra_current) {
 997                                         (void)xfs_da_reada_buf(NULL, dp,
 998                                                 map[ra_index].br_startoff +
 999                                                 ra_offset, XFS_DATA_FORK);
1000                                         ra_current = i;
1001                                 }
1002                                 /*
1003                                  * Advance offset through the mapping table.
1004                                  */
1005                                 for (j = 0; j < mp->m_dirblkfsbs; j++) {
1006                                         /*
1007                                          * The rest of this extent but not
1008                                          * more than a dir block.
1009                                          */
1010                                         length = MIN(mp->m_dirblkfsbs,
1011                                                 (int)(map[ra_index].br_blockcount -
1012                                                 ra_offset));
1013                                         j += length;
1014                                         ra_offset += length;
1015                                         /*
1016                                          * Advance to the next mapping if
1017                                          * this one is used up.
1018                                          */
1019                                         if (ra_offset ==
1020                                             map[ra_index].br_blockcount) {
1021                                                 ra_offset = 0;
1022                                                 ra_index++;
1023                                         }
1024                                 }
1025                         }
1026                         /*
1027                          * Having done a read, we need to set a new offset.
1028                          */
1029                         newoff = xfs_dir2_db_off_to_byte(mp, curdb, 0);
1030                         /*
1031                          * Start of the current block.
1032                          */
1033                         if (curoff < newoff)
1034                                 curoff = newoff;
1035                         /*
1036                          * Make sure we're in the right block.
1037                          */
1038                         else if (curoff > newoff)
1039                                 ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
1040                                        curdb);
1041                         hdr = bp->data;
1042                         xfs_dir2_data_check(dp, bp);
1043                         /*
1044                          * Find our position in the block.
1045                          */
1046                         ptr = (char *)(hdr + 1);
1047                         byteoff = xfs_dir2_byte_to_off(mp, curoff);
1048                         /*
1049                          * Skip past the header.
1050                          */
1051                         if (byteoff == 0)
1052                                 curoff += (uint)sizeof(*hdr);
1053                         /*
1054                          * Skip past entries until we reach our offset.
1055                          */
1056                         else {
1057                                 while ((char *)ptr - (char *)hdr < byteoff) {
1058                                         dup = (xfs_dir2_data_unused_t *)ptr;
1059
1060                                         if (be16_to_cpu(dup->freetag)
1061                                                   == XFS_DIR2_DATA_FREE_TAG) {
1062
1063                                                 length = be16_to_cpu(dup->length);
1064                                                 ptr += length;
1065                                                 continue;
1066                                         }
1067                                         dep = (xfs_dir2_data_entry_t *)ptr;
1068                                         length =
1069                                            xfs_dir2_data_entsize(dep->namelen);
1070                                         ptr += length;
1071                                 }
1072                                 /*
1073                                  * Now set our real offset.
1074                                  */
1075                                 curoff =
1076                                         xfs_dir2_db_off_to_byte(mp,
1077                                             xfs_dir2_byte_to_db(mp, curoff),
1078                                             (char *)ptr - (char *)hdr);
1079                                 if (ptr >= (char *)hdr + mp->m_dirblksize) {
1080                                         continue;
1081                                 }
1082                         }
1083                 }
1084                 /*
1085                  * We have a pointer to an entry.
1086                  * Is it a live one?
1087                  */
1088                 dup = (xfs_dir2_data_unused_t *)ptr;
1089                 /*
1090                  * No, it's unused, skip over it.
1091                  */
1092                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
1093                         length = be16_to_cpu(dup->length);
1094                         ptr += length;
1095                         curoff += length;
1096                         continue;
1097                 }
1098
1099                 dep = (xfs_dir2_data_entry_t *)ptr;
1100                 length = xfs_dir2_data_entsize(dep->namelen);
1101
1102                 if (filldir(dirent, (char *)dep->name, dep->namelen,
1103                             xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff,
1104                             be64_to_cpu(dep->inumber), DT_UNKNOWN))
1105                         break;
1106
1107                 /*
1108                  * Advance to next entry in the block.
1109                  */
1110                 ptr += length;
1111                 curoff += length;
1112                 /* bufsize may have just been a guess; don't go negative */
1113                 bufsize = bufsize > length ? bufsize - length : 0;
1114         }
1115
1116         /*
1117          * All done.  Set output offset value to current offset.
1118          */
1119         if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
1120                 *offset = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
1121         else
1122                 *offset = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
1123         kmem_free(map);
1124         if (bp)
1125                 xfs_da_brelse(NULL, bp);
1126         return error;
1127 }
1128
1129 /*
1130  * Initialize a new leaf block, leaf1 or leafn magic accepted.
1131  */
1132 int
1133 xfs_dir2_leaf_init(
1134         xfs_da_args_t           *args,          /* operation arguments */
1135         xfs_dir2_db_t           bno,            /* directory block number */
1136         xfs_dabuf_t             **bpp,          /* out: leaf buffer */
1137         int                     magic)          /* magic number for block */
1138 {
1139         xfs_dabuf_t             *bp;            /* leaf buffer */
1140         xfs_inode_t             *dp;            /* incore directory inode */
1141         int                     error;          /* error return code */
1142         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1143         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1144         xfs_mount_t             *mp;            /* filesystem mount point */
1145         xfs_trans_t             *tp;            /* transaction pointer */
1146
1147         dp = args->dp;
1148         ASSERT(dp != NULL);
1149         tp = args->trans;
1150         mp = dp->i_mount;
1151         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
1152                bno < XFS_DIR2_FREE_FIRSTDB(mp));
1153         /*
1154          * Get the buffer for the block.
1155          */
1156         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
1157                 XFS_DATA_FORK);
1158         if (error) {
1159                 return error;
1160         }
1161         ASSERT(bp != NULL);
1162         leaf = bp->data;
1163         /*
1164          * Initialize the header.
1165          */
1166         leaf->hdr.info.magic = cpu_to_be16(magic);
1167         leaf->hdr.info.forw = 0;
1168         leaf->hdr.info.back = 0;
1169         leaf->hdr.count = 0;
1170         leaf->hdr.stale = 0;
1171         xfs_dir2_leaf_log_header(tp, bp);
1172         /*
1173          * If it's a leaf-format directory initialize the tail.
1174          * In this case our caller has the real bests table to copy into
1175          * the block.
1176          */
1177         if (magic == XFS_DIR2_LEAF1_MAGIC) {
1178                 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1179                 ltp->bestcount = 0;
1180                 xfs_dir2_leaf_log_tail(tp, bp);
1181         }
1182         *bpp = bp;
1183         return 0;
1184 }
1185
1186 /*
1187  * Log the bests entries indicated from a leaf1 block.
1188  */
1189 static void
1190 xfs_dir2_leaf_log_bests(
1191         xfs_trans_t             *tp,            /* transaction pointer */
1192         xfs_dabuf_t             *bp,            /* leaf buffer */
1193         int                     first,          /* first entry to log */
1194         int                     last)           /* last entry to log */
1195 {
1196         __be16                  *firstb;        /* pointer to first entry */
1197         __be16                  *lastb;         /* pointer to last entry */
1198         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1199         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1200
1201         leaf = bp->data;
1202         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
1203         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1204         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1205         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1206         xfs_da_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1207                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1208 }
1209
1210 /*
1211  * Log the leaf entries indicated from a leaf1 or leafn block.
1212  */
1213 void
1214 xfs_dir2_leaf_log_ents(
1215         xfs_trans_t             *tp,            /* transaction pointer */
1216         xfs_dabuf_t             *bp,            /* leaf buffer */
1217         int                     first,          /* first entry to log */
1218         int                     last)           /* last entry to log */
1219 {
1220         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1221         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1222         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1223
1224         leaf = bp->data;
1225         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1226                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1227         firstlep = &leaf->ents[first];
1228         lastlep = &leaf->ents[last];
1229         xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1230                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1231 }
1232
1233 /*
1234  * Log the header of the leaf1 or leafn block.
1235  */
1236 void
1237 xfs_dir2_leaf_log_header(
1238         xfs_trans_t             *tp,            /* transaction pointer */
1239         xfs_dabuf_t             *bp)            /* leaf buffer */
1240 {
1241         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1242
1243         leaf = bp->data;
1244         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1245                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1246         xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1247                 (uint)(sizeof(leaf->hdr) - 1));
1248 }
1249
1250 /*
1251  * Log the tail of the leaf1 block.
1252  */
1253 STATIC void
1254 xfs_dir2_leaf_log_tail(
1255         xfs_trans_t             *tp,            /* transaction pointer */
1256         xfs_dabuf_t             *bp)            /* leaf buffer */
1257 {
1258         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1259         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1260         xfs_mount_t             *mp;            /* filesystem mount point */
1261
1262         mp = tp->t_mountp;
1263         leaf = bp->data;
1264         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC));
1265         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1266         xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1267                 (uint)(mp->m_dirblksize - 1));
1268 }
1269
1270 /*
1271  * Look up the entry referred to by args in the leaf format directory.
1272  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1273  * is also used by the node-format code.
1274  */
1275 int
1276 xfs_dir2_leaf_lookup(
1277         xfs_da_args_t           *args)          /* operation arguments */
1278 {
1279         xfs_dabuf_t             *dbp;           /* data block buffer */
1280         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1281         xfs_inode_t             *dp;            /* incore directory inode */
1282         int                     error;          /* error return code */
1283         int                     index;          /* found entry index */
1284         xfs_dabuf_t             *lbp;           /* leaf buffer */
1285         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1286         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1287         xfs_trans_t             *tp;            /* transaction pointer */
1288
1289         trace_xfs_dir2_leaf_lookup(args);
1290
1291         /*
1292          * Look up name in the leaf block, returning both buffers and index.
1293          */
1294         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1295                 return error;
1296         }
1297         tp = args->trans;
1298         dp = args->dp;
1299         xfs_dir2_leaf_check(dp, lbp);
1300         leaf = lbp->data;
1301         /*
1302          * Get to the leaf entry and contained data entry address.
1303          */
1304         lep = &leaf->ents[index];
1305         /*
1306          * Point to the data entry.
1307          */
1308         dep = (xfs_dir2_data_entry_t *)
1309               ((char *)dbp->data +
1310                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1311         /*
1312          * Return the found inode number & CI name if appropriate
1313          */
1314         args->inumber = be64_to_cpu(dep->inumber);
1315         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1316         xfs_da_brelse(tp, dbp);
1317         xfs_da_brelse(tp, lbp);
1318         return XFS_ERROR(error);
1319 }
1320
1321 /*
1322  * Look up name/hash in the leaf block.
1323  * Fill in indexp with the found index, and dbpp with the data buffer.
1324  * If not found dbpp will be NULL, and ENOENT comes back.
1325  * lbpp will always be filled in with the leaf buffer unless there's an error.
1326  */
1327 static int                                      /* error */
1328 xfs_dir2_leaf_lookup_int(
1329         xfs_da_args_t           *args,          /* operation arguments */
1330         xfs_dabuf_t             **lbpp,         /* out: leaf buffer */
1331         int                     *indexp,        /* out: index in leaf block */
1332         xfs_dabuf_t             **dbpp)         /* out: data buffer */
1333 {
1334         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1335         xfs_dabuf_t             *dbp = NULL;    /* data buffer */
1336         xfs_dir2_data_entry_t   *dep;           /* data entry */
1337         xfs_inode_t             *dp;            /* incore directory inode */
1338         int                     error;          /* error return code */
1339         int                     index;          /* index in leaf block */
1340         xfs_dabuf_t             *lbp;           /* leaf buffer */
1341         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1342         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1343         xfs_mount_t             *mp;            /* filesystem mount point */
1344         xfs_dir2_db_t           newdb;          /* new data block number */
1345         xfs_trans_t             *tp;            /* transaction pointer */
1346         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1347         enum xfs_dacmp          cmp;            /* name compare result */
1348
1349         dp = args->dp;
1350         tp = args->trans;
1351         mp = dp->i_mount;
1352         /*
1353          * Read the leaf block into the buffer.
1354          */
1355         error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1356                                                         XFS_DATA_FORK);
1357         if (error)
1358                 return error;
1359         *lbpp = lbp;
1360         leaf = lbp->data;
1361         xfs_dir2_leaf_check(dp, lbp);
1362         /*
1363          * Look for the first leaf entry with our hash value.
1364          */
1365         index = xfs_dir2_leaf_search_hash(args, lbp);
1366         /*
1367          * Loop over all the entries with the right hash value
1368          * looking to match the name.
1369          */
1370         for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
1371                                 be32_to_cpu(lep->hashval) == args->hashval;
1372                                 lep++, index++) {
1373                 /*
1374                  * Skip over stale leaf entries.
1375                  */
1376                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1377                         continue;
1378                 /*
1379                  * Get the new data block number.
1380                  */
1381                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1382                 /*
1383                  * If it's not the same as the old data block number,
1384                  * need to pitch the old one and read the new one.
1385                  */
1386                 if (newdb != curdb) {
1387                         if (dbp)
1388                                 xfs_da_brelse(tp, dbp);
1389                         error = xfs_da_read_buf(tp, dp,
1390                                                 xfs_dir2_db_to_da(mp, newdb),
1391                                                 -1, &dbp, XFS_DATA_FORK);
1392                         if (error) {
1393                                 xfs_da_brelse(tp, lbp);
1394                                 return error;
1395                         }
1396                         xfs_dir2_data_check(dp, dbp);
1397                         curdb = newdb;
1398                 }
1399                 /*
1400                  * Point to the data entry.
1401                  */
1402                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->data +
1403                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1404                 /*
1405                  * Compare name and if it's an exact match, return the index
1406                  * and buffer. If it's the first case-insensitive match, store
1407                  * the index and buffer and continue looking for an exact match.
1408                  */
1409                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1410                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1411                         args->cmpresult = cmp;
1412                         *indexp = index;
1413                         /* case exact match: return the current buffer. */
1414                         if (cmp == XFS_CMP_EXACT) {
1415                                 *dbpp = dbp;
1416                                 return 0;
1417                         }
1418                         cidb = curdb;
1419                 }
1420         }
1421         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1422         /*
1423          * Here, we can only be doing a lookup (not a rename or remove).
1424          * If a case-insensitive match was found earlier, re-read the
1425          * appropriate data block if required and return it.
1426          */
1427         if (args->cmpresult == XFS_CMP_CASE) {
1428                 ASSERT(cidb != -1);
1429                 if (cidb != curdb) {
1430                         xfs_da_brelse(tp, dbp);
1431                         error = xfs_da_read_buf(tp, dp,
1432                                                 xfs_dir2_db_to_da(mp, cidb),
1433                                                 -1, &dbp, XFS_DATA_FORK);
1434                         if (error) {
1435                                 xfs_da_brelse(tp, lbp);
1436                                 return error;
1437                         }
1438                 }
1439                 *dbpp = dbp;
1440                 return 0;
1441         }
1442         /*
1443          * No match found, return ENOENT.
1444          */
1445         ASSERT(cidb == -1);
1446         if (dbp)
1447                 xfs_da_brelse(tp, dbp);
1448         xfs_da_brelse(tp, lbp);
1449         return XFS_ERROR(ENOENT);
1450 }
1451
1452 /*
1453  * Remove an entry from a leaf format directory.
1454  */
1455 int                                             /* error */
1456 xfs_dir2_leaf_removename(
1457         xfs_da_args_t           *args)          /* operation arguments */
1458 {
1459         __be16                  *bestsp;        /* leaf block best freespace */
1460         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1461         xfs_dir2_db_t           db;             /* data block number */
1462         xfs_dabuf_t             *dbp;           /* data block buffer */
1463         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1464         xfs_inode_t             *dp;            /* incore directory inode */
1465         int                     error;          /* error return code */
1466         xfs_dir2_db_t           i;              /* temporary data block # */
1467         int                     index;          /* index into leaf entries */
1468         xfs_dabuf_t             *lbp;           /* leaf buffer */
1469         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1470         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1471         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1472         xfs_mount_t             *mp;            /* filesystem mount point */
1473         int                     needlog;        /* need to log data header */
1474         int                     needscan;       /* need to rescan data frees */
1475         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1476         xfs_trans_t             *tp;            /* transaction pointer */
1477
1478         trace_xfs_dir2_leaf_removename(args);
1479
1480         /*
1481          * Lookup the leaf entry, get the leaf and data blocks read in.
1482          */
1483         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1484                 return error;
1485         }
1486         dp = args->dp;
1487         tp = args->trans;
1488         mp = dp->i_mount;
1489         leaf = lbp->data;
1490         hdr = dbp->data;
1491         xfs_dir2_data_check(dp, dbp);
1492         /*
1493          * Point to the leaf entry, use that to point to the data entry.
1494          */
1495         lep = &leaf->ents[index];
1496         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1497         dep = (xfs_dir2_data_entry_t *)
1498               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1499         needscan = needlog = 0;
1500         oldbest = be16_to_cpu(hdr->bestfree[0].length);
1501         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1502         bestsp = xfs_dir2_leaf_bests_p(ltp);
1503         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1504         /*
1505          * Mark the former data entry unused.
1506          */
1507         xfs_dir2_data_make_free(tp, dbp,
1508                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1509                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1510         /*
1511          * We just mark the leaf entry stale by putting a null in it.
1512          */
1513         be16_add_cpu(&leaf->hdr.stale, 1);
1514         xfs_dir2_leaf_log_header(tp, lbp);
1515         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1516         xfs_dir2_leaf_log_ents(tp, lbp, index, index);
1517         /*
1518          * Scan the freespace in the data block again if necessary,
1519          * log the data block header if necessary.
1520          */
1521         if (needscan)
1522                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1523         if (needlog)
1524                 xfs_dir2_data_log_header(tp, dbp);
1525         /*
1526          * If the longest freespace in the data block has changed,
1527          * put the new value in the bests table and log that.
1528          */
1529         if (be16_to_cpu(hdr->bestfree[0].length) != oldbest) {
1530                 bestsp[db] = hdr->bestfree[0].length;
1531                 xfs_dir2_leaf_log_bests(tp, lbp, db, db);
1532         }
1533         xfs_dir2_data_check(dp, dbp);
1534         /*
1535          * If the data block is now empty then get rid of the data block.
1536          */
1537         if (be16_to_cpu(hdr->bestfree[0].length) ==
1538             mp->m_dirblksize - (uint)sizeof(*hdr)) {
1539                 ASSERT(db != mp->m_dirdatablk);
1540                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1541                         /*
1542                          * Nope, can't get rid of it because it caused
1543                          * allocation of a bmap btree block to do so.
1544                          * Just go on, returning success, leaving the
1545                          * empty block in place.
1546                          */
1547                         if (error == ENOSPC && args->total == 0) {
1548                                 xfs_da_buf_done(dbp);
1549                                 error = 0;
1550                         }
1551                         xfs_dir2_leaf_check(dp, lbp);
1552                         xfs_da_buf_done(lbp);
1553                         return error;
1554                 }
1555                 dbp = NULL;
1556                 /*
1557                  * If this is the last data block then compact the
1558                  * bests table by getting rid of entries.
1559                  */
1560                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1561                         /*
1562                          * Look for the last active entry (i).
1563                          */
1564                         for (i = db - 1; i > 0; i--) {
1565                                 if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1566                                         break;
1567                         }
1568                         /*
1569                          * Copy the table down so inactive entries at the
1570                          * end are removed.
1571                          */
1572                         memmove(&bestsp[db - i], bestsp,
1573                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1574                         be32_add_cpu(&ltp->bestcount, -(db - i));
1575                         xfs_dir2_leaf_log_tail(tp, lbp);
1576                         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1577                 } else
1578                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1579         }
1580         /*
1581          * If the data block was not the first one, drop it.
1582          */
1583         else if (db != mp->m_dirdatablk && dbp != NULL) {
1584                 xfs_da_buf_done(dbp);
1585                 dbp = NULL;
1586         }
1587         xfs_dir2_leaf_check(dp, lbp);
1588         /*
1589          * See if we can convert to block form.
1590          */
1591         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1592 }
1593
1594 /*
1595  * Replace the inode number in a leaf format directory entry.
1596  */
1597 int                                             /* error */
1598 xfs_dir2_leaf_replace(
1599         xfs_da_args_t           *args)          /* operation arguments */
1600 {
1601         xfs_dabuf_t             *dbp;           /* data block buffer */
1602         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1603         xfs_inode_t             *dp;            /* incore directory inode */
1604         int                     error;          /* error return code */
1605         int                     index;          /* index of leaf entry */
1606         xfs_dabuf_t             *lbp;           /* leaf buffer */
1607         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1608         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1609         xfs_trans_t             *tp;            /* transaction pointer */
1610
1611         trace_xfs_dir2_leaf_replace(args);
1612
1613         /*
1614          * Look up the entry.
1615          */
1616         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1617                 return error;
1618         }
1619         dp = args->dp;
1620         leaf = lbp->data;
1621         /*
1622          * Point to the leaf entry, get data address from it.
1623          */
1624         lep = &leaf->ents[index];
1625         /*
1626          * Point to the data entry.
1627          */
1628         dep = (xfs_dir2_data_entry_t *)
1629               ((char *)dbp->data +
1630                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1631         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1632         /*
1633          * Put the new inode number in, log it.
1634          */
1635         dep->inumber = cpu_to_be64(args->inumber);
1636         tp = args->trans;
1637         xfs_dir2_data_log_entry(tp, dbp, dep);
1638         xfs_da_buf_done(dbp);
1639         xfs_dir2_leaf_check(dp, lbp);
1640         xfs_da_brelse(tp, lbp);
1641         return 0;
1642 }
1643
1644 /*
1645  * Return index in the leaf block (lbp) which is either the first
1646  * one with this hash value, or if there are none, the insert point
1647  * for that hash value.
1648  */
1649 int                                             /* index value */
1650 xfs_dir2_leaf_search_hash(
1651         xfs_da_args_t           *args,          /* operation arguments */
1652         xfs_dabuf_t             *lbp)           /* leaf buffer */
1653 {
1654         xfs_dahash_t            hash=0;         /* hash from this entry */
1655         xfs_dahash_t            hashwant;       /* hash value looking for */
1656         int                     high;           /* high leaf index */
1657         int                     low;            /* low leaf index */
1658         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1659         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1660         int                     mid=0;          /* current leaf index */
1661
1662         leaf = lbp->data;
1663 #ifndef __KERNEL__
1664         if (!leaf->hdr.count)
1665                 return 0;
1666 #endif
1667         /*
1668          * Note, the table cannot be empty, so we have to go through the loop.
1669          * Binary search the leaf entries looking for our hash value.
1670          */
1671         for (lep = leaf->ents, low = 0, high = be16_to_cpu(leaf->hdr.count) - 1,
1672                 hashwant = args->hashval;
1673              low <= high; ) {
1674                 mid = (low + high) >> 1;
1675                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1676                         break;
1677                 if (hash < hashwant)
1678                         low = mid + 1;
1679                 else
1680                         high = mid - 1;
1681         }
1682         /*
1683          * Found one, back up through all the equal hash values.
1684          */
1685         if (hash == hashwant) {
1686                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1687                         mid--;
1688                 }
1689         }
1690         /*
1691          * Need to point to an entry higher than ours.
1692          */
1693         else if (hash < hashwant)
1694                 mid++;
1695         return mid;
1696 }
1697
1698 /*
1699  * Trim off a trailing data block.  We know it's empty since the leaf
1700  * freespace table says so.
1701  */
1702 int                                             /* error */
1703 xfs_dir2_leaf_trim_data(
1704         xfs_da_args_t           *args,          /* operation arguments */
1705         xfs_dabuf_t             *lbp,           /* leaf buffer */
1706         xfs_dir2_db_t           db)             /* data block number */
1707 {
1708         __be16                  *bestsp;        /* leaf bests table */
1709         xfs_dabuf_t             *dbp;           /* data block buffer */
1710         xfs_inode_t             *dp;            /* incore directory inode */
1711         int                     error;          /* error return value */
1712         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1713         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1714         xfs_mount_t             *mp;            /* filesystem mount point */
1715         xfs_trans_t             *tp;            /* transaction pointer */
1716
1717         dp = args->dp;
1718         mp = dp->i_mount;
1719         tp = args->trans;
1720         /*
1721          * Read the offending data block.  We need its buffer.
1722          */
1723         if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp,
1724                         XFS_DATA_FORK))) {
1725                 return error;
1726         }
1727
1728         leaf = lbp->data;
1729         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1730
1731 #ifdef DEBUG
1732 {
1733         struct xfs_dir2_data_hdr *hdr = dbp->data;
1734
1735         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
1736         ASSERT(be16_to_cpu(hdr->bestfree[0].length) ==
1737                mp->m_dirblksize - (uint)sizeof(*hdr));
1738         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1739 }
1740 #endif
1741
1742         /*
1743          * Get rid of the data block.
1744          */
1745         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1746                 ASSERT(error != ENOSPC);
1747                 xfs_da_brelse(tp, dbp);
1748                 return error;
1749         }
1750         /*
1751          * Eliminate the last bests entry from the table.
1752          */
1753         bestsp = xfs_dir2_leaf_bests_p(ltp);
1754         be32_add_cpu(&ltp->bestcount, -1);
1755         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1756         xfs_dir2_leaf_log_tail(tp, lbp);
1757         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1758         return 0;
1759 }
1760
1761 static inline size_t
1762 xfs_dir2_leaf_size(
1763         struct xfs_dir2_leaf_hdr        *hdr,
1764         int                             counts)
1765 {
1766         int                     entries;
1767
1768         entries = be16_to_cpu(hdr->count) - be16_to_cpu(hdr->stale);
1769         return sizeof(xfs_dir2_leaf_hdr_t) +
1770             entries * sizeof(xfs_dir2_leaf_entry_t) +
1771             counts * sizeof(xfs_dir2_data_off_t) +
1772             sizeof(xfs_dir2_leaf_tail_t);
1773 }
1774
1775 /*
1776  * Convert node form directory to leaf form directory.
1777  * The root of the node form dir needs to already be a LEAFN block.
1778  * Just return if we can't do anything.
1779  */
1780 int                                             /* error */
1781 xfs_dir2_node_to_leaf(
1782         xfs_da_state_t          *state)         /* directory operation state */
1783 {
1784         xfs_da_args_t           *args;          /* operation arguments */
1785         xfs_inode_t             *dp;            /* incore directory inode */
1786         int                     error;          /* error return code */
1787         xfs_dabuf_t             *fbp;           /* buffer for freespace block */
1788         xfs_fileoff_t           fo;             /* freespace file offset */
1789         xfs_dir2_free_t         *free;          /* freespace structure */
1790         xfs_dabuf_t             *lbp;           /* buffer for leaf block */
1791         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1792         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1793         xfs_mount_t             *mp;            /* filesystem mount point */
1794         int                     rval;           /* successful free trim? */
1795         xfs_trans_t             *tp;            /* transaction pointer */
1796
1797         /*
1798          * There's more than a leaf level in the btree, so there must
1799          * be multiple leafn blocks.  Give up.
1800          */
1801         if (state->path.active > 1)
1802                 return 0;
1803         args = state->args;
1804
1805         trace_xfs_dir2_node_to_leaf(args);
1806
1807         mp = state->mp;
1808         dp = args->dp;
1809         tp = args->trans;
1810         /*
1811          * Get the last offset in the file.
1812          */
1813         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1814                 return error;
1815         }
1816         fo -= mp->m_dirblkfsbs;
1817         /*
1818          * If there are freespace blocks other than the first one,
1819          * take this opportunity to remove trailing empty freespace blocks
1820          * that may have been left behind during no-space-reservation
1821          * operations.
1822          */
1823         while (fo > mp->m_dirfreeblk) {
1824                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1825                         return error;
1826                 }
1827                 if (rval)
1828                         fo -= mp->m_dirblkfsbs;
1829                 else
1830                         return 0;
1831         }
1832         /*
1833          * Now find the block just before the freespace block.
1834          */
1835         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1836                 return error;
1837         }
1838         /*
1839          * If it's not the single leaf block, give up.
1840          */
1841         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1842                 return 0;
1843         lbp = state->path.blk[0].bp;
1844         leaf = lbp->data;
1845         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1846         /*
1847          * Read the freespace block.
1848          */
1849         if ((error = xfs_da_read_buf(tp, dp, mp->m_dirfreeblk, -1, &fbp,
1850                         XFS_DATA_FORK))) {
1851                 return error;
1852         }
1853         free = fbp->data;
1854         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1855         ASSERT(!free->hdr.firstdb);
1856
1857         /*
1858          * Now see if the leafn and free data will fit in a leaf1.
1859          * If not, release the buffer and give up.
1860          */
1861         if (xfs_dir2_leaf_size(&leaf->hdr, be32_to_cpu(free->hdr.nvalid)) >
1862                         mp->m_dirblksize) {
1863                 xfs_da_brelse(tp, fbp);
1864                 return 0;
1865         }
1866
1867         /*
1868          * If the leaf has any stale entries in it, compress them out.
1869          * The compact routine will log the header.
1870          */
1871         if (be16_to_cpu(leaf->hdr.stale))
1872                 xfs_dir2_leaf_compact(args, lbp);
1873         else
1874                 xfs_dir2_leaf_log_header(tp, lbp);
1875         leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAF1_MAGIC);
1876         /*
1877          * Set up the leaf tail from the freespace block.
1878          */
1879         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1880         ltp->bestcount = free->hdr.nvalid;
1881         /*
1882          * Set up the leaf bests table.
1883          */
1884         memcpy(xfs_dir2_leaf_bests_p(ltp), free->bests,
1885                 be32_to_cpu(ltp->bestcount) * sizeof(xfs_dir2_data_off_t));
1886         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1887         xfs_dir2_leaf_log_tail(tp, lbp);
1888         xfs_dir2_leaf_check(dp, lbp);
1889         /*
1890          * Get rid of the freespace block.
1891          */
1892         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1893         if (error) {
1894                 /*
1895                  * This can't fail here because it can only happen when
1896                  * punching out the middle of an extent, and this is an
1897                  * isolated block.
1898                  */
1899                 ASSERT(error != ENOSPC);
1900                 return error;
1901         }
1902         fbp = NULL;
1903         /*
1904          * Now see if we can convert the single-leaf directory
1905          * down to a block form directory.
1906          * This routine always kills the dabuf for the leaf, so
1907          * eliminate it from the path.
1908          */
1909         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1910         state->path.blk[0].bp = NULL;
1911         return error;
1912 }