git.oblomov.eu Git - linux-2.6/blob - 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_dir.h"
  28 #include "xfs_dir2.h"
  29 #include "xfs_dmapi.h"
  30 #include "xfs_mount.h"
  31 #include "xfs_da_btree.h"
  32 #include "xfs_bmap_btree.h"
  33 #include "xfs_attr_sf.h"
  34 #include "xfs_dir_sf.h"
  35 #include "xfs_dir2_sf.h"
  36 #include "xfs_dinode.h"
  37 #include "xfs_inode.h"
  38 #include "xfs_bmap.h"
  39 #include "xfs_dir2_data.h"
  40 #include "xfs_dir2_leaf.h"
  41 #include "xfs_dir2_block.h"
  42 #include "xfs_dir2_node.h"
  43 #include "xfs_dir2_trace.h"
  44 #include "xfs_error.h"
  45
  46 /*
  47  * Local function declarations.
  48  */
  49 #ifdef DEBUG
  50 static void xfs_dir2_leaf_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
  51 #else
  52 #define xfs_dir2_leaf_check(dp, bp)
  53 #endif
  54 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **lbpp,
  55                                     int *indexp, xfs_dabuf_t **dbpp);
  56 static void xfs_dir2_leaf_log_bests(struct xfs_trans *tp, struct xfs_dabuf *bp,
  57                                     int first, int last);
  58 static void xfs_dir2_leaf_log_tail(struct xfs_trans *tp, struct xfs_dabuf *bp);
  59
  60
  61 /*
  62  * Convert a block form directory to a leaf form directory.
  63  */
  64 int                                             /* error */
  65 xfs_dir2_block_to_leaf(
  66         xfs_da_args_t           *args,          /* operation arguments */
  67         xfs_dabuf_t             *dbp)           /* input block's buffer */
  68 {
  69         __be16                  *bestsp;        /* leaf's bestsp entries */
  70         xfs_dablk_t             blkno;          /* leaf block's bno */
  71         xfs_dir2_block_t        *block;         /* block structure */
  72         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
  73         xfs_dir2_block_tail_t   *btp;           /* block's tail */
  74         xfs_inode_t             *dp;            /* incore directory inode */
  75         int                     error;          /* error return code */
  76         xfs_dabuf_t             *lbp;           /* leaf block's buffer */
  77         xfs_dir2_db_t           ldb;            /* leaf block's bno */
  78         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
  79         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
  80         xfs_mount_t             *mp;            /* filesystem mount point */
  81         int                     needlog;        /* need to log block header */
  82         int                     needscan;       /* need to rescan bestfree */
  83         xfs_trans_t             *tp;            /* transaction pointer */
  84
  85         xfs_dir2_trace_args_b("block_to_leaf", args, dbp);
  86         dp = args->dp;
  87         mp = dp->i_mount;
  88         tp = args->trans;
  89         /*
  90          * Add the leaf block to the inode.
  91          * This interface will only put blocks in the leaf/node range.
  92          * Since that's empty now, we'll get the root (block 0 in range).
  93          */
  94         if ((error = xfs_da_grow_inode(args, &blkno))) {
  95                 return error;
  96         }
  97         ldb = XFS_DIR2_DA_TO_DB(mp, blkno);
  98         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
  99         /*
 100          * Initialize the leaf block, get a buffer for it.
 101          */
 102         if ((error = xfs_dir2_leaf_init(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC))) {
 103                 return error;
 104         }
 105         ASSERT(lbp != NULL);
 106         leaf = lbp->data;
 107         block = dbp->data;
 108         xfs_dir2_data_check(dp, dbp);
 109         btp = XFS_DIR2_BLOCK_TAIL_P(mp, block);
 110         blp = XFS_DIR2_BLOCK_LEAF_P(btp);
 111         /*
 112          * Set the counts in the leaf header.
 113          */
 114         INT_COPY(leaf->hdr.count, btp->count, ARCH_CONVERT); /* INT_: type change */
 115         INT_COPY(leaf->hdr.stale, btp->stale, ARCH_CONVERT); /* INT_: type change */
 116         /*
 117          * Could compact these but I think we always do the conversion
 118          * after squeezing out stale entries.
 119          */
 120         memcpy(leaf->ents, blp, INT_GET(btp->count, ARCH_CONVERT) * sizeof(xfs_dir2_leaf_entry_t));
 121         xfs_dir2_leaf_log_ents(tp, lbp, 0, INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1);
 122         needscan = 0;
 123         needlog = 1;
 124         /*
 125          * Make the space formerly occupied by the leaf entries and block
 126          * tail be free.
 127          */
 128         xfs_dir2_data_make_free(tp, dbp,
 129                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)block),
 130                 (xfs_dir2_data_aoff_t)((char *)block + mp->m_dirblksize -
 131                                        (char *)blp),
 132                 &needlog, &needscan);
 133         /*
 134          * Fix up the block header, make it a data block.
 135          */
 136         block->hdr.magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 137         if (needscan)
 138                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog,
 139                         NULL);
 140         /*
 141          * Set up leaf tail and bests table.
 142          */
 143         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
 144         ltp->bestcount = cpu_to_be32(1);
 145         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
 146         bestsp[0] =  block->hdr.bestfree[0].length;
 147         /*
 148          * Log the data header and leaf bests table.
 149          */
 150         if (needlog)
 151                 xfs_dir2_data_log_header(tp, dbp);
 152         xfs_dir2_leaf_check(dp, lbp);
 153         xfs_dir2_data_check(dp, dbp);
 154         xfs_dir2_leaf_log_bests(tp, lbp, 0, 0);
 155         xfs_da_buf_done(lbp);
 156         return 0;
 157 }
 158
 159 /*
 160  * Add an entry to a leaf form directory.
 161  */
 162 int                                             /* error */
 163 xfs_dir2_leaf_addname(
 164         xfs_da_args_t           *args)          /* operation arguments */
 165 {
 166         __be16                  *bestsp;        /* freespace table in leaf */
 167         int                     compact;        /* need to compact leaves */
 168         xfs_dir2_data_t         *data;          /* data block structure */
 169         xfs_dabuf_t             *dbp;           /* data block buffer */
 170         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 171         xfs_inode_t             *dp;            /* incore directory inode */
 172         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 173         int                     error;          /* error return value */
 174         int                     grown;          /* allocated new data block */
 175         int                     highstale;      /* index of next stale leaf */
 176         int                     i;              /* temporary, index */
 177         int                     index;          /* leaf table position */
 178         xfs_dabuf_t             *lbp;           /* leaf's buffer */
 179         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 180         int                     length;         /* length of new entry */
 181         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 182         int                     lfloglow;       /* low leaf logging index */
 183         int                     lfloghigh;      /* high leaf logging index */
 184         int                     lowstale;       /* index of prev stale leaf */
 185         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 186         xfs_mount_t             *mp;            /* filesystem mount point */
 187         int                     needbytes;      /* leaf block bytes needed */
 188         int                     needlog;        /* need to log data header */
 189         int                     needscan;       /* need to rescan data free */
 190         xfs_dir2_data_off_t     *tagp;          /* end of data entry */
 191         xfs_trans_t             *tp;            /* transaction pointer */
 192         xfs_dir2_db_t           use_block;      /* data block number */
 193
 194         xfs_dir2_trace_args("leaf_addname", args);
 195         dp = args->dp;
 196         tp = args->trans;
 197         mp = dp->i_mount;
 198         /*
 199          * Read the leaf block.
 200          */
 201         error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
 202                 XFS_DATA_FORK);
 203         if (error) {
 204                 return error;
 205         }
 206         ASSERT(lbp != NULL);
 207         /*
 208          * Look up the entry by hash value and name.
 209          * We know it's not there, our caller has already done a lookup.
 210          * So the index is of the entry to insert in front of.
 211          * But if there are dup hash values the index is of the first of those.
 212          */
 213         index = xfs_dir2_leaf_search_hash(args, lbp);
 214         leaf = lbp->data;
 215         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
 216         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
 217         length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
 218         /*
 219          * See if there are any entries with the same hash value
 220          * and space in their block for the new entry.
 221          * This is good because it puts multiple same-hash value entries
 222          * in a data block, improving the lookup of those entries.
 223          */
 224         for (use_block = -1, lep = &leaf->ents[index];
 225              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
 226              index++, lep++) {
 227                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 228                         continue;
 229                 i = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
 230                 ASSERT(i < be32_to_cpu(ltp->bestcount));
 231                 ASSERT(be16_to_cpu(bestsp[i]) != NULLDATAOFF);
 232                 if (be16_to_cpu(bestsp[i]) >= length) {
 233                         use_block = i;
 234                         break;
 235                 }
 236         }
 237         /*
 238          * Didn't find a block yet, linear search all the data blocks.
 239          */
 240         if (use_block == -1) {
 241                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 242                         /*
 243                          * Remember a block we see that's missing.
 244                          */
 245                         if (be16_to_cpu(bestsp[i]) == NULLDATAOFF && use_block == -1)
 246                                 use_block = i;
 247                         else if (be16_to_cpu(bestsp[i]) >= length) {
 248                                 use_block = i;
 249                                 break;
 250                         }
 251                 }
 252         }
 253         /*
 254          * How many bytes do we need in the leaf block?
 255          */
 256         needbytes =
 257                 (leaf->hdr.stale ? 0 : (uint)sizeof(leaf->ents[0])) +
 258                 (use_block != -1 ? 0 : (uint)sizeof(leaf->bests[0]));
 259         /*
 260          * Now kill use_block if it refers to a missing block, so we
 261          * can use it as an indication of allocation needed.
 262          */
 263         if (use_block != -1 && be16_to_cpu(bestsp[use_block]) == NULLDATAOFF)
 264                 use_block = -1;
 265         /*
 266          * If we don't have enough free bytes but we can make enough
 267          * by compacting out stale entries, we'll do that.
 268          */
 269         if ((char *)bestsp - (char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] < needbytes &&
 270             INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1) {
 271                 compact = 1;
 272         }
 273         /*
 274          * Otherwise if we don't have enough free bytes we need to
 275          * convert to node form.
 276          */
 277         else if ((char *)bestsp - (char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] <
 278                  needbytes) {
 279                 /*
 280                  * Just checking or no space reservation, give up.
 281                  */
 282                 if (args->justcheck || args->total == 0) {
 283                         xfs_da_brelse(tp, lbp);
 284                         return XFS_ERROR(ENOSPC);
 285                 }
 286                 /*
 287                  * Convert to node form.
 288                  */
 289                 error = xfs_dir2_leaf_to_node(args, lbp);
 290                 xfs_da_buf_done(lbp);
 291                 if (error)
 292                         return error;
 293                 /*
 294                  * Then add the new entry.
 295                  */
 296                 return xfs_dir2_node_addname(args);
 297         }
 298         /*
 299          * Otherwise it will fit without compaction.
 300          */
 301         else
 302                 compact = 0;
 303         /*
 304          * If just checking, then it will fit unless we needed to allocate
 305          * a new data block.
 306          */
 307         if (args->justcheck) {
 308                 xfs_da_brelse(tp, lbp);
 309                 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
 310         }
 311         /*
 312          * If no allocations are allowed, return now before we've
 313          * changed anything.
 314          */
 315         if (args->total == 0 && use_block == -1) {
 316                 xfs_da_brelse(tp, lbp);
 317                 return XFS_ERROR(ENOSPC);
 318         }
 319         /*
 320          * Need to compact the leaf entries, removing stale ones.
 321          * Leave one stale entry behind - the one closest to our
 322          * insertion index - and we'll shift that one to our insertion
 323          * point later.
 324          */
 325         if (compact) {
 326                 xfs_dir2_leaf_compact_x1(lbp, &index, &lowstale, &highstale,
 327                         &lfloglow, &lfloghigh);
 328         }
 329         /*
 330          * There are stale entries, so we'll need log-low and log-high
 331          * impossibly bad values later.
 332          */
 333         else if (INT_GET(leaf->hdr.stale, ARCH_CONVERT)) {
 334                 lfloglow = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 335                 lfloghigh = -1;
 336         }
 337         /*
 338          * If there was no data block space found, we need to allocate
 339          * a new one.
 340          */
 341         if (use_block == -1) {
 342                 /*
 343                  * Add the new data block.
 344                  */
 345                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 346                                 &use_block))) {
 347                         xfs_da_brelse(tp, lbp);
 348                         return error;
 349                 }
 350                 /*
 351                  * Initialize the block.
 352                  */
 353                 if ((error = xfs_dir2_data_init(args, use_block, &dbp))) {
 354                         xfs_da_brelse(tp, lbp);
 355                         return error;
 356                 }
 357                 /*
 358                  * If we're adding a new data block on the end we need to
 359                  * extend the bests table.  Copy it up one entry.
 360                  */
 361                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
 362                         bestsp--;
 363                         memmove(&bestsp[0], &bestsp[1],
 364                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 365                         be32_add(&ltp->bestcount, 1);
 366                         xfs_dir2_leaf_log_tail(tp, lbp);
 367                         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
 368                 }
 369                 /*
 370                  * If we're filling in a previously empty block just log it.
 371                  */
 372                 else
 373                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
 374                 data = dbp->data;
 375                 bestsp[use_block] = data->hdr.bestfree[0].length;
 376                 grown = 1;
 377         }
 378         /*
 379          * Already had space in some data block.
 380          * Just read that one in.
 381          */
 382         else {
 383                 if ((error =
 384                     xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, use_block),
 385                             -1, &dbp, XFS_DATA_FORK))) {
 386                         xfs_da_brelse(tp, lbp);
 387                         return error;
 388                 }
 389                 data = dbp->data;
 390                 grown = 0;
 391         }
 392         xfs_dir2_data_check(dp, dbp);
 393         /*
 394          * Point to the biggest freespace in our data block.
 395          */
 396         dup = (xfs_dir2_data_unused_t *)
 397               ((char *)data + be16_to_cpu(data->hdr.bestfree[0].offset));
 398         ASSERT(be16_to_cpu(dup->length) >= length);
 399         needscan = needlog = 0;
 400         /*
 401          * Mark the initial part of our freespace in use for the new entry.
 402          */
 403         xfs_dir2_data_use_free(tp, dbp, dup,
 404                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)data), length,
 405                 &needlog, &needscan);
 406         /*
 407          * Initialize our new entry (at last).
 408          */
 409         dep = (xfs_dir2_data_entry_t *)dup;
 410         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
 411         dep->namelen = args->namelen;
 412         memcpy(dep->name, args->name, dep->namelen);
 413         tagp = XFS_DIR2_DATA_ENTRY_TAG_P(dep);
 414         INT_SET(*tagp, ARCH_CONVERT, (xfs_dir2_data_off_t)((char *)dep - (char *)data));
 415         /*
 416          * Need to scan fix up the bestfree table.
 417          */
 418         if (needscan)
 419                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
 420         /*
 421          * Need to log the data block's header.
 422          */
 423         if (needlog)
 424                 xfs_dir2_data_log_header(tp, dbp);
 425         xfs_dir2_data_log_entry(tp, dbp, dep);
 426         /*
 427          * If the bests table needs to be changed, do it.
 428          * Log the change unless we've already done that.
 429          */
 430         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(data->hdr.bestfree[0].length)) {
 431                 bestsp[use_block] = data->hdr.bestfree[0].length;
 432                 if (!grown)
 433                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
 434         }
 435         /*
 436          * Now we need to make room to insert the leaf entry.
 437          * If there are no stale entries, we just insert a hole at index.
 438          */
 439         if (!leaf->hdr.stale) {
 440                 /*
 441                  * lep is still good as the index leaf entry.
 442                  */
 443                 if (index < INT_GET(leaf->hdr.count, ARCH_CONVERT))
 444                         memmove(lep + 1, lep,
 445                                 (INT_GET(leaf->hdr.count, ARCH_CONVERT) - index) * sizeof(*lep));
 446                 /*
 447                  * Record low and high logging indices for the leaf.
 448                  */
 449                 lfloglow = index;
 450                 lfloghigh = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 451                 INT_MOD(leaf->hdr.count, ARCH_CONVERT, +1);
 452         }
 453         /*
 454          * There are stale entries.
 455          * We will use one of them for the new entry.
 456          * It's probably not at the right location, so we'll have to
 457          * shift some up or down first.
 458          */
 459         else {
 460                 /*
 461                  * If we didn't compact before, we need to find the nearest
 462                  * stale entries before and after our insertion point.
 463                  */
 464                 if (compact == 0) {
 465                         /*
 466                          * Find the first stale entry before the insertion
 467                          * point, if any.
 468                          */
 469                         for (lowstale = index - 1;
 470                              lowstale >= 0 &&
 471                                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) !=
 472                                 XFS_DIR2_NULL_DATAPTR;
 473                              lowstale--)
 474                                 continue;
 475                         /*
 476                          * Find the next stale entry at or after the insertion
 477                          * point, if any.   Stop if we go so far that the
 478                          * lowstale entry would be better.
 479                          */
 480                         for (highstale = index;
 481                              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
 482                                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) !=
 483                                 XFS_DIR2_NULL_DATAPTR &&
 484                                 (lowstale < 0 ||
 485                                  index - lowstale - 1 >= highstale - index);
 486                              highstale++)
 487                                 continue;
 488                 }
 489                 /*
 490                  * If the low one is better, use it.
 491                  */
 492                 if (lowstale >= 0 &&
 493                     (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 494                      index - lowstale - 1 < highstale - index)) {
 495                         ASSERT(index - lowstale - 1 >= 0);
 496                         ASSERT(INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) ==
 497                                XFS_DIR2_NULL_DATAPTR);
 498                         /*
 499                          * Copy entries up to cover the stale entry
 500                          * and make room for the new entry.
 501                          */
 502                         if (index - lowstale - 1 > 0)
 503                                 memmove(&leaf->ents[lowstale],
 504                                         &leaf->ents[lowstale + 1],
 505                                         (index - lowstale - 1) * sizeof(*lep));
 506                         lep = &leaf->ents[index - 1];
 507                         lfloglow = MIN(lowstale, lfloglow);
 508                         lfloghigh = MAX(index - 1, lfloghigh);
 509                 }
 510                 /*
 511                  * The high one is better, so use that one.
 512                  */
 513                 else {
 514                         ASSERT(highstale - index >= 0);
 515                         ASSERT(INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) ==
 516                                XFS_DIR2_NULL_DATAPTR);
 517                         /*
 518                          * Copy entries down to copver the stale entry
 519                          * and make room for the new entry.
 520                          */
 521                         if (highstale - index > 0)
 522                                 memmove(&leaf->ents[index + 1],
 523                                         &leaf->ents[index],
 524                                         (highstale - index) * sizeof(*lep));
 525                         lep = &leaf->ents[index];
 526                         lfloglow = MIN(index, lfloglow);
 527                         lfloghigh = MAX(highstale, lfloghigh);
 528                 }
 529                 INT_MOD(leaf->hdr.stale, ARCH_CONVERT, -1);
 530         }
 531         /*
 532          * Fill in the new leaf entry.
 533          */
 534         INT_SET(lep->hashval, ARCH_CONVERT, args->hashval);
 535         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_DB_OFF_TO_DATAPTR(mp, use_block, INT_GET(*tagp, ARCH_CONVERT)));
 536         /*
 537          * Log the leaf fields and give up the buffers.
 538          */
 539         xfs_dir2_leaf_log_header(tp, lbp);
 540         xfs_dir2_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
 541         xfs_dir2_leaf_check(dp, lbp);
 542         xfs_da_buf_done(lbp);
 543         xfs_dir2_data_check(dp, dbp);
 544         xfs_da_buf_done(dbp);
 545         return 0;
 546 }
 547
 548 #ifdef DEBUG
 549 /*
 550  * Check the internal consistency of a leaf1 block.
 551  * Pop an assert if something is wrong.
 552  */
 553 void
 554 xfs_dir2_leaf_check(
 555         xfs_inode_t             *dp,            /* incore directory inode */
 556         xfs_dabuf_t             *bp)            /* leaf's buffer */
 557 {
 558         int                     i;              /* leaf index */
 559         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 560         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 561         xfs_mount_t             *mp;            /* filesystem mount point */
 562         int                     stale;          /* count of stale leaves */
 563
 564         leaf = bp->data;
 565         mp = dp->i_mount;
 566         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
 567         /*
 568          * This value is not restrictive enough.
 569          * Should factor in the size of the bests table as well.
 570          * We can deduce a value for that from di_size.
 571          */
 572         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) <= XFS_DIR2_MAX_LEAF_ENTS(mp));
 573         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
 574         /*
 575          * Leaves and bests don't overlap.
 576          */
 577         ASSERT((char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] <=
 578                (char *)XFS_DIR2_LEAF_BESTS_P(ltp));
 579         /*
 580          * Check hash value order, count stale entries.
 581          */
 582         for (i = stale = 0; i < INT_GET(leaf->hdr.count, ARCH_CONVERT); i++) {
 583                 if (i + 1 < INT_GET(leaf->hdr.count, ARCH_CONVERT))
 584                         ASSERT(INT_GET(leaf->ents[i].hashval, ARCH_CONVERT) <=
 585                                INT_GET(leaf->ents[i + 1].hashval, ARCH_CONVERT));
 586                 if (INT_GET(leaf->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 587                         stale++;
 588         }
 589         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == stale);
 590 }
 591 #endif  /* DEBUG */
 592
 593 /*
 594  * Compact out any stale entries in the leaf.
 595  * Log the header and changed leaf entries, if any.
 596  */
 597 void
 598 xfs_dir2_leaf_compact(
 599         xfs_da_args_t   *args,          /* operation arguments */
 600         xfs_dabuf_t     *bp)            /* leaf buffer */
 601 {
 602         int             from;           /* source leaf index */
 603         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 604         int             loglow;         /* first leaf entry to log */
 605         int             to;             /* target leaf index */
 606
 607         leaf = bp->data;
 608         if (!leaf->hdr.stale) {
 609                 return;
 610         }
 611         /*
 612          * Compress out the stale entries in place.
 613          */
 614         for (from = to = 0, loglow = -1; from < INT_GET(leaf->hdr.count, ARCH_CONVERT); from++) {
 615                 if (INT_GET(leaf->ents[from].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 616                         continue;
 617                 /*
 618                  * Only actually copy the entries that are different.
 619                  */
 620                 if (from > to) {
 621                         if (loglow == -1)
 622                                 loglow = to;
 623                         leaf->ents[to] = leaf->ents[from];
 624                 }
 625                 to++;
 626         }
 627         /*
 628          * Update and log the header, log the leaf entries.
 629          */
 630         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == from - to);
 631         INT_MOD(leaf->hdr.count, ARCH_CONVERT, -(INT_GET(leaf->hdr.stale, ARCH_CONVERT)));
 632         leaf->hdr.stale = 0;
 633         xfs_dir2_leaf_log_header(args->trans, bp);
 634         if (loglow != -1)
 635                 xfs_dir2_leaf_log_ents(args->trans, bp, loglow, to - 1);
 636 }
 637
 638 /*
 639  * Compact the leaf entries, removing stale ones.
 640  * Leave one stale entry behind - the one closest to our
 641  * insertion index - and the caller will shift that one to our insertion
 642  * point later.
 643  * Return new insertion index, where the remaining stale entry is,
 644  * and leaf logging indices.
 645  */
 646 void
 647 xfs_dir2_leaf_compact_x1(
 648         xfs_dabuf_t     *bp,            /* leaf buffer */
 649         int             *indexp,        /* insertion index */
 650         int             *lowstalep,     /* out: stale entry before us */
 651         int             *highstalep,    /* out: stale entry after us */
 652         int             *lowlogp,       /* out: low log index */
 653         int             *highlogp)      /* out: high log index */
 654 {
 655         int             from;           /* source copy index */
 656         int             highstale;      /* stale entry at/after index */
 657         int             index;          /* insertion index */
 658         int             keepstale;      /* source index of kept stale */
 659         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 660         int             lowstale;       /* stale entry before index */
 661         int             newindex=0;     /* new insertion index */
 662         int             to;             /* destination copy index */
 663
 664         leaf = bp->data;
 665         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1);
 666         index = *indexp;
 667         /*
 668          * Find the first stale entry before our index, if any.
 669          */
 670         for (lowstale = index - 1;
 671              lowstale >= 0 &&
 672                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) != XFS_DIR2_NULL_DATAPTR;
 673              lowstale--)
 674                 continue;
 675         /*
 676          * Find the first stale entry at or after our index, if any.
 677          * Stop if the answer would be worse than lowstale.
 678          */
 679         for (highstale = index;
 680              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
 681                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) != XFS_DIR2_NULL_DATAPTR &&
 682                 (lowstale < 0 || index - lowstale > highstale - index);
 683              highstale++)
 684                 continue;
 685         /*
 686          * Pick the better of lowstale and highstale.
 687          */
 688         if (lowstale >= 0 &&
 689             (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 690              index - lowstale <= highstale - index))
 691                 keepstale = lowstale;
 692         else
 693                 keepstale = highstale;
 694         /*
 695          * Copy the entries in place, removing all the stale entries
 696          * except keepstale.
 697          */
 698         for (from = to = 0; from < INT_GET(leaf->hdr.count, ARCH_CONVERT); from++) {
 699                 /*
 700                  * Notice the new value of index.
 701                  */
 702                 if (index == from)
 703                         newindex = to;
 704                 if (from != keepstale &&
 705                     INT_GET(leaf->ents[from].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR) {
 706                         if (from == to)
 707                                 *lowlogp = to;
 708                         continue;
 709                 }
 710                 /*
 711                  * Record the new keepstale value for the insertion.
 712                  */
 713                 if (from == keepstale)
 714                         lowstale = highstale = to;
 715                 /*
 716                  * Copy only the entries that have moved.
 717                  */
 718                 if (from > to)
 719                         leaf->ents[to] = leaf->ents[from];
 720                 to++;
 721         }
 722         ASSERT(from > to);
 723         /*
 724          * If the insertion point was past the last entry,
 725          * set the new insertion point accordingly.
 726          */
 727         if (index == from)
 728                 newindex = to;
 729         *indexp = newindex;
 730         /*
 731          * Adjust the leaf header values.
 732          */
 733         INT_MOD(leaf->hdr.count, ARCH_CONVERT, -(from - to));
 734         INT_SET(leaf->hdr.stale, ARCH_CONVERT, 1);
 735         /*
 736          * Remember the low/high stale value only in the "right"
 737          * direction.
 738          */
 739         if (lowstale >= newindex)
 740                 lowstale = -1;
 741         else
 742                 highstale = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 743         *highlogp = INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1;
 744         *lowstalep = lowstale;
 745         *highstalep = highstale;
 746 }
 747
 748 /*
 749  * Getdents (readdir) for leaf and node directories.
 750  * This reads the data blocks only, so is the same for both forms.
 751  */
 752 int                                             /* error */
 753 xfs_dir2_leaf_getdents(
 754         xfs_trans_t             *tp,            /* transaction pointer */
 755         xfs_inode_t             *dp,            /* incore directory inode */
 756         uio_t                   *uio,           /* I/O control & vectors */
 757         int                     *eofp,          /* out: reached end of dir */
 758         xfs_dirent_t            *dbp,           /* caller's buffer */
 759         xfs_dir2_put_t          put)            /* ABI formatting routine */
 760 {
 761         xfs_dabuf_t             *bp;            /* data block buffer */
 762         int                     byteoff;        /* offset in current block */
 763         xfs_dir2_db_t           curdb;          /* db for current block */
 764         xfs_dir2_off_t          curoff;         /* current overall offset */
 765         xfs_dir2_data_t         *data;          /* data block structure */
 766         xfs_dir2_data_entry_t   *dep;           /* data entry */
 767         xfs_dir2_data_unused_t  *dup;           /* unused entry */
 768         int                     eof;            /* reached end of directory */
 769         int                     error = 0;      /* error return value */
 770         int                     i;              /* temporary loop index */
 771         int                     j;              /* temporary loop index */
 772         int                     length;         /* temporary length value */
 773         xfs_bmbt_irec_t         *map;           /* map vector for blocks */
 774         xfs_extlen_t            map_blocks;     /* number of fsbs in map */
 775         xfs_dablk_t             map_off;        /* last mapped file offset */
 776         int                     map_size;       /* total entries in *map */
 777         int                     map_valid;      /* valid entries in *map */
 778         xfs_mount_t             *mp;            /* filesystem mount point */
 779         xfs_dir2_off_t          newoff;         /* new curoff after new blk */
 780         int                     nmap;           /* mappings to ask xfs_bmapi */
 781         xfs_dir2_put_args_t     *p;             /* formatting arg bundle */
 782         char                    *ptr = NULL;    /* pointer to current data */
 783         int                     ra_current;     /* number of read-ahead blks */
 784         int                     ra_index;       /* *map index for read-ahead */
 785         int                     ra_offset;      /* map entry offset for ra */
 786         int                     ra_want;        /* readahead count wanted */
 787
 788         /*
 789          * If the offset is at or past the largest allowed value,
 790          * give up right away, return eof.
 791          */
 792         if (uio->uio_offset >= XFS_DIR2_MAX_DATAPTR) {
 793                 *eofp = 1;
 794                 return 0;
 795         }
 796         mp = dp->i_mount;
 797         /*
 798          * Setup formatting arguments.
 799          */
 800         p = kmem_alloc(sizeof(*p), KM_SLEEP);
 801         p->dbp = dbp;
 802         p->put = put;
 803         p->uio = uio;
 804         /*
 805          * Set up to bmap a number of blocks based on the caller's
 806          * buffer size, the directory block size, and the filesystem
 807          * block size.
 808          */
 809         map_size =
 810                 howmany(uio->uio_resid + mp->m_dirblksize,
 811                         mp->m_sb.sb_blocksize);
 812         map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
 813         map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
 814         bp = NULL;
 815         eof = 1;
 816         /*
 817          * Inside the loop we keep the main offset value as a byte offset
 818          * in the directory file.
 819          */
 820         curoff = XFS_DIR2_DATAPTR_TO_BYTE(mp, uio->uio_offset);
 821         /*
 822          * Force this conversion through db so we truncate the offset
 823          * down to get the start of the data block.
 824          */
 825         map_off = XFS_DIR2_DB_TO_DA(mp, XFS_DIR2_BYTE_TO_DB(mp, curoff));
 826         /*
 827          * Loop over directory entries until we reach the end offset.
 828          * Get more blocks and readahead as necessary.
 829          */
 830         while (curoff < XFS_DIR2_LEAF_OFFSET) {
 831                 /*
 832                  * If we have no buffer, or we're off the end of the
 833                  * current buffer, need to get another one.
 834                  */
 835                 if (!bp || ptr >= (char *)bp->data + mp->m_dirblksize) {
 836                         /*
 837                          * If we have a buffer, we need to release it and
 838                          * take it out of the mapping.
 839                          */
 840                         if (bp) {
 841                                 xfs_da_brelse(tp, bp);
 842                                 bp = NULL;
 843                                 map_blocks -= mp->m_dirblkfsbs;
 844                                 /*
 845                                  * Loop to get rid of the extents for the
 846                                  * directory block.
 847                                  */
 848                                 for (i = mp->m_dirblkfsbs; i > 0; ) {
 849                                         j = MIN((int)map->br_blockcount, i);
 850                                         map->br_blockcount -= j;
 851                                         map->br_startblock += j;
 852                                         map->br_startoff += j;
 853                                         /*
 854                                          * If mapping is done, pitch it from
 855                                          * the table.
 856                                          */
 857                                         if (!map->br_blockcount && --map_valid)
 858                                                 memmove(&map[0], &map[1],
 859                                                         sizeof(map[0]) *
 860                                                         map_valid);
 861                                         i -= j;
 862                                 }
 863                         }
 864                         /*
 865                          * Recalculate the readahead blocks wanted.
 866                          */
 867                         ra_want = howmany(uio->uio_resid + mp->m_dirblksize,
 868                                           mp->m_sb.sb_blocksize) - 1;
 869                         /*
 870                          * If we don't have as many as we want, and we haven't
 871                          * run out of data blocks, get some more mappings.
 872                          */
 873                         if (1 + ra_want > map_blocks &&
 874                             map_off <
 875                             XFS_DIR2_BYTE_TO_DA(mp, XFS_DIR2_LEAF_OFFSET)) {
 876                                 /*
 877                                  * Get more bmaps, fill in after the ones
 878                                  * we already have in the table.
 879                                  */
 880                                 nmap = map_size - map_valid;
 881                                 error = xfs_bmapi(tp, dp,
 882                                         map_off,
 883                                         XFS_DIR2_BYTE_TO_DA(mp,
 884                                                 XFS_DIR2_LEAF_OFFSET) - map_off,
 885                                         XFS_BMAPI_METADATA, NULL, 0,
 886                                         &map[map_valid], &nmap, NULL);
 887                                 /*
 888                                  * Don't know if we should ignore this or
 889                                  * try to return an error.
 890                                  * The trouble with returning errors
 891                                  * is that readdir will just stop without
 892                                  * actually passing the error through.
 893                                  */
 894                                 if (error)
 895                                         break;  /* XXX */
 896                                 /*
 897                                  * If we got all the mappings we asked for,
 898                                  * set the final map offset based on the
 899                                  * last bmap value received.
 900                                  * Otherwise, we've reached the end.
 901                                  */
 902                                 if (nmap == map_size - map_valid)
 903                                         map_off =
 904                                         map[map_valid + nmap - 1].br_startoff +
 905                                         map[map_valid + nmap - 1].br_blockcount;
 906                                 else
 907                                         map_off =
 908                                                 XFS_DIR2_BYTE_TO_DA(mp,
 909                                                         XFS_DIR2_LEAF_OFFSET);
 910                                 /*
 911                                  * Look for holes in the mapping, and
 912                                  * eliminate them.  Count up the valid blocks.
 913                                  */
 914                                 for (i = map_valid; i < map_valid + nmap; ) {
 915                                         if (map[i].br_startblock ==
 916                                             HOLESTARTBLOCK) {
 917                                                 nmap--;
 918                                                 length = map_valid + nmap - i;
 919                                                 if (length)
 920                                                         memmove(&map[i],
 921                                                                 &map[i + 1],
 922                                                                 sizeof(map[i]) *
 923                                                                 length);
 924                                         } else {
 925                                                 map_blocks +=
 926                                                         map[i].br_blockcount;
 927                                                 i++;
 928                                         }
 929                                 }
 930                                 map_valid += nmap;
 931                         }
 932                         /*
 933                          * No valid mappings, so no more data blocks.
 934                          */
 935                         if (!map_valid) {
 936                                 curoff = XFS_DIR2_DA_TO_BYTE(mp, map_off);
 937                                 break;
 938                         }
 939                         /*
 940                          * Read the directory block starting at the first
 941                          * mapping.
 942                          */
 943                         curdb = XFS_DIR2_DA_TO_DB(mp, map->br_startoff);
 944                         error = xfs_da_read_buf(tp, dp, map->br_startoff,
 945                                 map->br_blockcount >= mp->m_dirblkfsbs ?
 946                                     XFS_FSB_TO_DADDR(mp, map->br_startblock) :
 947                                     -1,
 948                                 &bp, XFS_DATA_FORK);
 949                         /*
 950                          * Should just skip over the data block instead
 951                          * of giving up.
 952                          */
 953                         if (error)
 954                                 break;  /* XXX */
 955                         /*
 956                          * Adjust the current amount of read-ahead: we just
 957                          * read a block that was previously ra.
 958                          */
 959                         if (ra_current)
 960                                 ra_current -= mp->m_dirblkfsbs;
 961                         /*
 962                          * Do we need more readahead?
 963                          */
 964                         for (ra_index = ra_offset = i = 0;
 965                              ra_want > ra_current && i < map_blocks;
 966                              i += mp->m_dirblkfsbs) {
 967                                 ASSERT(ra_index < map_valid);
 968                                 /*
 969                                  * Read-ahead a contiguous directory block.
 970                                  */
 971                                 if (i > ra_current &&
 972                                     map[ra_index].br_blockcount >=
 973                                     mp->m_dirblkfsbs) {
 974                                         xfs_baread(mp->m_ddev_targp,
 975                                                 XFS_FSB_TO_DADDR(mp,
 976                                                    map[ra_index].br_startblock +
 977                                                    ra_offset),
 978                                                 (int)BTOBB(mp->m_dirblksize));
 979                                         ra_current = i;
 980                                 }
 981                                 /*
 982                                  * Read-ahead a non-contiguous directory block.
 983                                  * This doesn't use our mapping, but this
 984                                  * is a very rare case.
 985                                  */
 986                                 else if (i > ra_current) {
 987                                         (void)xfs_da_reada_buf(tp, dp,
 988                                                 map[ra_index].br_startoff +
 989                                                 ra_offset, XFS_DATA_FORK);
 990                                         ra_current = i;
 991                                 }
 992                                 /*
 993                                  * Advance offset through the mapping table.
 994                                  */
 995                                 for (j = 0; j < mp->m_dirblkfsbs; j++) {
 996                                         /*
 997                                          * The rest of this extent but not
 998                                          * more than a dir block.
 999                                          */
1000                                         length = MIN(mp->m_dirblkfsbs,
1001                                                 (int)(map[ra_index].br_blockcount -
1002                                                 ra_offset));
1003                                         j += length;
1004                                         ra_offset += length;
1005                                         /*
1006                                          * Advance to the next mapping if
1007                                          * this one is used up.
1008                                          */
1009                                         if (ra_offset ==
1010                                             map[ra_index].br_blockcount) {
1011                                                 ra_offset = 0;
1012                                                 ra_index++;
1013                                         }
1014                                 }
1015                         }
1016                         /*
1017                          * Having done a read, we need to set a new offset.
1018                          */
1019                         newoff = XFS_DIR2_DB_OFF_TO_BYTE(mp, curdb, 0);
1020                         /*
1021                          * Start of the current block.
1022                          */
1023                         if (curoff < newoff)
1024                                 curoff = newoff;
1025                         /*
1026                          * Make sure we're in the right block.
1027                          */
1028                         else if (curoff > newoff)
1029                                 ASSERT(XFS_DIR2_BYTE_TO_DB(mp, curoff) ==
1030                                        curdb);
1031                         data = bp->data;
1032                         xfs_dir2_data_check(dp, bp);
1033                         /*
1034                          * Find our position in the block.
1035                          */
1036                         ptr = (char *)&data->u;
1037                         byteoff = XFS_DIR2_BYTE_TO_OFF(mp, curoff);
1038                         /*
1039                          * Skip past the header.
1040                          */
1041                         if (byteoff == 0)
1042                                 curoff += (uint)sizeof(data->hdr);
1043                         /*
1044                          * Skip past entries until we reach our offset.
1045                          */
1046                         else {
1047                                 while ((char *)ptr - (char *)data < byteoff) {
1048                                         dup = (xfs_dir2_data_unused_t *)ptr;
1049
1050                                         if (be16_to_cpu(dup->freetag)
1051                                                   == XFS_DIR2_DATA_FREE_TAG) {
1052
1053                                                 length = be16_to_cpu(dup->length);
1054                                                 ptr += length;
1055                                                 continue;
1056                                         }
1057                                         dep = (xfs_dir2_data_entry_t *)ptr;
1058                                         length =
1059                                            XFS_DIR2_DATA_ENTSIZE(dep->namelen);
1060                                         ptr += length;
1061                                 }
1062                                 /*
1063                                  * Now set our real offset.
1064                                  */
1065                                 curoff =
1066                                         XFS_DIR2_DB_OFF_TO_BYTE(mp,
1067                                             XFS_DIR2_BYTE_TO_DB(mp, curoff),
1068                                             (char *)ptr - (char *)data);
1069                                 if (ptr >= (char *)data + mp->m_dirblksize) {
1070                                         continue;
1071                                 }
1072                         }
1073                 }
1074                 /*
1075                  * We have a pointer to an entry.
1076                  * Is it a live one?
1077                  */
1078                 dup = (xfs_dir2_data_unused_t *)ptr;
1079                 /*
1080                  * No, it's unused, skip over it.
1081                  */
1082                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
1083                         length = be16_to_cpu(dup->length);
1084                         ptr += length;
1085                         curoff += length;
1086                         continue;
1087                 }
1088
1089                 /*
1090                  * Copy the entry into the putargs, and try formatting it.
1091                  */
1092                 dep = (xfs_dir2_data_entry_t *)ptr;
1093
1094                 p->namelen = dep->namelen;
1095
1096                 length = XFS_DIR2_DATA_ENTSIZE(p->namelen);
1097
1098                 p->cook = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff + length);
1099
1100                 p->ino = INT_GET(dep->inumber, ARCH_CONVERT);
1101 #if XFS_BIG_INUMS
1102                 p->ino += mp->m_inoadd;
1103 #endif
1104                 p->name = (char *)dep->name;
1105
1106                 error = p->put(p);
1107
1108                 /*
1109                  * Won't fit.  Return to caller.
1110                  */
1111                 if (!p->done) {
1112                         eof = 0;
1113                         break;
1114                 }
1115                 /*
1116                  * Advance to next entry in the block.
1117                  */
1118                 ptr += length;
1119                 curoff += length;
1120         }
1121
1122         /*
1123          * All done.  Set output offset value to current offset.
1124          */
1125         *eofp = eof;
1126         if (curoff > XFS_DIR2_DATAPTR_TO_BYTE(mp, XFS_DIR2_MAX_DATAPTR))
1127                 uio->uio_offset = XFS_DIR2_MAX_DATAPTR;
1128         else
1129                 uio->uio_offset = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff);
1130         kmem_free(map, map_size * sizeof(*map));
1131         kmem_free(p, sizeof(*p));
1132         if (bp)
1133                 xfs_da_brelse(tp, bp);
1134         return error;
1135 }
1136
1137 /*
1138  * Initialize a new leaf block, leaf1 or leafn magic accepted.
1139  */
1140 int
1141 xfs_dir2_leaf_init(
1142         xfs_da_args_t           *args,          /* operation arguments */
1143         xfs_dir2_db_t           bno,            /* directory block number */
1144         xfs_dabuf_t             **bpp,          /* out: leaf buffer */
1145         int                     magic)          /* magic number for block */
1146 {
1147         xfs_dabuf_t             *bp;            /* leaf buffer */
1148         xfs_inode_t             *dp;            /* incore directory inode */
1149         int                     error;          /* error return code */
1150         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1151         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1152         xfs_mount_t             *mp;            /* filesystem mount point */
1153         xfs_trans_t             *tp;            /* transaction pointer */
1154
1155         dp = args->dp;
1156         ASSERT(dp != NULL);
1157         tp = args->trans;
1158         mp = dp->i_mount;
1159         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
1160                bno < XFS_DIR2_FREE_FIRSTDB(mp));
1161         /*
1162          * Get the buffer for the block.
1163          */
1164         error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, bno), -1, &bp,
1165                 XFS_DATA_FORK);
1166         if (error) {
1167                 return error;
1168         }
1169         ASSERT(bp != NULL);
1170         leaf = bp->data;
1171         /*
1172          * Initialize the header.
1173          */
1174         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, magic);
1175         leaf->hdr.info.forw = 0;
1176         leaf->hdr.info.back = 0;
1177         leaf->hdr.count = 0;
1178         leaf->hdr.stale = 0;
1179         xfs_dir2_leaf_log_header(tp, bp);
1180         /*
1181          * If it's a leaf-format directory initialize the tail.
1182          * In this case our caller has the real bests table to copy into
1183          * the block.
1184          */
1185         if (magic == XFS_DIR2_LEAF1_MAGIC) {
1186                 ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1187                 ltp->bestcount = 0;
1188                 xfs_dir2_leaf_log_tail(tp, bp);
1189         }
1190         *bpp = bp;
1191         return 0;
1192 }
1193
1194 /*
1195  * Log the bests entries indicated from a leaf1 block.
1196  */
1197 static void
1198 xfs_dir2_leaf_log_bests(
1199         xfs_trans_t             *tp,            /* transaction pointer */
1200         xfs_dabuf_t             *bp,            /* leaf buffer */
1201         int                     first,          /* first entry to log */
1202         int                     last)           /* last entry to log */
1203 {
1204         __be16                  *firstb;        /* pointer to first entry */
1205         __be16                  *lastb;         /* pointer to last entry */
1206         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1207         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1208
1209         leaf = bp->data;
1210         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
1211         ltp = XFS_DIR2_LEAF_TAIL_P(tp->t_mountp, leaf);
1212         firstb = XFS_DIR2_LEAF_BESTS_P(ltp) + first;
1213         lastb = XFS_DIR2_LEAF_BESTS_P(ltp) + last;
1214         xfs_da_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1215                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1216 }
1217
1218 /*
1219  * Log the leaf entries indicated from a leaf1 or leafn block.
1220  */
1221 void
1222 xfs_dir2_leaf_log_ents(
1223         xfs_trans_t             *tp,            /* transaction pointer */
1224         xfs_dabuf_t             *bp,            /* leaf buffer */
1225         int                     first,          /* first entry to log */
1226         int                     last)           /* last entry to log */
1227 {
1228         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1229         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1230         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1231
1232         leaf = bp->data;
1233         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC ||
1234                INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1235         firstlep = &leaf->ents[first];
1236         lastlep = &leaf->ents[last];
1237         xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1238                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1239 }
1240
1241 /*
1242  * Log the header of the leaf1 or leafn block.
1243  */
1244 void
1245 xfs_dir2_leaf_log_header(
1246         xfs_trans_t             *tp,            /* transaction pointer */
1247         xfs_dabuf_t             *bp)            /* leaf buffer */
1248 {
1249         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1250
1251         leaf = bp->data;
1252         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC ||
1253                INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1254         xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1255                 (uint)(sizeof(leaf->hdr) - 1));
1256 }
1257
1258 /*
1259  * Log the tail of the leaf1 block.
1260  */
1261 STATIC void
1262 xfs_dir2_leaf_log_tail(
1263         xfs_trans_t             *tp,            /* transaction pointer */
1264         xfs_dabuf_t             *bp)            /* leaf buffer */
1265 {
1266         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1267         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1268         xfs_mount_t             *mp;            /* filesystem mount point */
1269
1270         mp = tp->t_mountp;
1271         leaf = bp->data;
1272         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
1273         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1274         xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1275                 (uint)(mp->m_dirblksize - 1));
1276 }
1277
1278 /*
1279  * Look up the entry referred to by args in the leaf format directory.
1280  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1281  * is also used by the node-format code.
1282  */
1283 int
1284 xfs_dir2_leaf_lookup(
1285         xfs_da_args_t           *args)          /* operation arguments */
1286 {
1287         xfs_dabuf_t             *dbp;           /* data block buffer */
1288         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1289         xfs_inode_t             *dp;            /* incore directory inode */
1290         int                     error;          /* error return code */
1291         int                     index;          /* found entry index */
1292         xfs_dabuf_t             *lbp;           /* leaf buffer */
1293         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1294         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1295         xfs_trans_t             *tp;            /* transaction pointer */
1296
1297         xfs_dir2_trace_args("leaf_lookup", args);
1298         /*
1299          * Look up name in the leaf block, returning both buffers and index.
1300          */
1301         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1302                 return error;
1303         }
1304         tp = args->trans;
1305         dp = args->dp;
1306         xfs_dir2_leaf_check(dp, lbp);
1307         leaf = lbp->data;
1308         /*
1309          * Get to the leaf entry and contained data entry address.
1310          */
1311         lep = &leaf->ents[index];
1312         /*
1313          * Point to the data entry.
1314          */
1315         dep = (xfs_dir2_data_entry_t *)
1316               ((char *)dbp->data +
1317                XFS_DIR2_DATAPTR_TO_OFF(dp->i_mount, INT_GET(lep->address, ARCH_CONVERT)));
1318         /*
1319          * Return the found inode number.
1320          */
1321         args->inumber = INT_GET(dep->inumber, ARCH_CONVERT);
1322         xfs_da_brelse(tp, dbp);
1323         xfs_da_brelse(tp, lbp);
1324         return XFS_ERROR(EEXIST);
1325 }
1326
1327 /*
1328  * Look up name/hash in the leaf block.
1329  * Fill in indexp with the found index, and dbpp with the data buffer.
1330  * If not found dbpp will be NULL, and ENOENT comes back.
1331  * lbpp will always be filled in with the leaf buffer unless there's an error.
1332  */
1333 static int                                      /* error */
1334 xfs_dir2_leaf_lookup_int(
1335         xfs_da_args_t           *args,          /* operation arguments */
1336         xfs_dabuf_t             **lbpp,         /* out: leaf buffer */
1337         int                     *indexp,        /* out: index in leaf block */
1338         xfs_dabuf_t             **dbpp)         /* out: data buffer */
1339 {
1340         xfs_dir2_db_t           curdb;          /* current data block number */
1341         xfs_dabuf_t             *dbp;           /* data buffer */
1342         xfs_dir2_data_entry_t   *dep;           /* data entry */
1343         xfs_inode_t             *dp;            /* incore directory inode */
1344         int                     error;          /* error return code */
1345         int                     index;          /* index in leaf block */
1346         xfs_dabuf_t             *lbp;           /* leaf buffer */
1347         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1348         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1349         xfs_mount_t             *mp;            /* filesystem mount point */
1350         xfs_dir2_db_t           newdb;          /* new data block number */
1351         xfs_trans_t             *tp;            /* transaction pointer */
1352
1353         dp = args->dp;
1354         tp = args->trans;
1355         mp = dp->i_mount;
1356         /*
1357          * Read the leaf block into the buffer.
1358          */
1359         if ((error =
1360             xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1361                     XFS_DATA_FORK))) {
1362                 return error;
1363         }
1364         *lbpp = lbp;
1365         leaf = lbp->data;
1366         xfs_dir2_leaf_check(dp, lbp);
1367         /*
1368          * Look for the first leaf entry with our hash value.
1369          */
1370         index = xfs_dir2_leaf_search_hash(args, lbp);
1371         /*
1372          * Loop over all the entries with the right hash value
1373          * looking to match the name.
1374          */
1375         for (lep = &leaf->ents[index], dbp = NULL, curdb = -1;
1376              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
1377              lep++, index++) {
1378                 /*
1379                  * Skip over stale leaf entries.
1380                  */
1381                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
1382                         continue;
1383                 /*
1384                  * Get the new data block number.
1385                  */
1386                 newdb = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
1387                 /*
1388                  * If it's not the same as the old data block number,
1389                  * need to pitch the old one and read the new one.
1390                  */
1391                 if (newdb != curdb) {
1392                         if (dbp)
1393                                 xfs_da_brelse(tp, dbp);
1394                         if ((error =
1395                             xfs_da_read_buf(tp, dp,
1396                                     XFS_DIR2_DB_TO_DA(mp, newdb), -1, &dbp,
1397                                     XFS_DATA_FORK))) {
1398                                 xfs_da_brelse(tp, lbp);
1399                                 return error;
1400                         }
1401                         xfs_dir2_data_check(dp, dbp);
1402                         curdb = newdb;
1403                 }
1404                 /*
1405                  * Point to the data entry.
1406                  */
1407                 dep = (xfs_dir2_data_entry_t *)
1408                       ((char *)dbp->data +
1409                        XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
1410                 /*
1411                  * If it matches then return it.
1412                  */
1413                 if (dep->namelen == args->namelen &&
1414                     dep->name[0] == args->name[0] &&
1415                     memcmp(dep->name, args->name, args->namelen) == 0) {
1416                         *dbpp = dbp;
1417                         *indexp = index;
1418                         return 0;
1419                 }
1420         }
1421         /*
1422          * No match found, return ENOENT.
1423          */
1424         ASSERT(args->oknoent);
1425         if (dbp)
1426                 xfs_da_brelse(tp, dbp);
1427         xfs_da_brelse(tp, lbp);
1428         return XFS_ERROR(ENOENT);
1429 }
1430
1431 /*
1432  * Remove an entry from a leaf format directory.
1433  */
1434 int                                             /* error */
1435 xfs_dir2_leaf_removename(
1436         xfs_da_args_t           *args)          /* operation arguments */
1437 {
1438         __be16                  *bestsp;        /* leaf block best freespace */
1439         xfs_dir2_data_t         *data;          /* data block structure */
1440         xfs_dir2_db_t           db;             /* data block number */
1441         xfs_dabuf_t             *dbp;           /* data block buffer */
1442         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1443         xfs_inode_t             *dp;            /* incore directory inode */
1444         int                     error;          /* error return code */
1445         xfs_dir2_db_t           i;              /* temporary data block # */
1446         int                     index;          /* index into leaf entries */
1447         xfs_dabuf_t             *lbp;           /* leaf buffer */
1448         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1449         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1450         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1451         xfs_mount_t             *mp;            /* filesystem mount point */
1452         int                     needlog;        /* need to log data header */
1453         int                     needscan;       /* need to rescan data frees */
1454         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1455         xfs_trans_t             *tp;            /* transaction pointer */
1456
1457         xfs_dir2_trace_args("leaf_removename", args);
1458         /*
1459          * Lookup the leaf entry, get the leaf and data blocks read in.
1460          */
1461         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1462                 return error;
1463         }
1464         dp = args->dp;
1465         tp = args->trans;
1466         mp = dp->i_mount;
1467         leaf = lbp->data;
1468         data = dbp->data;
1469         xfs_dir2_data_check(dp, dbp);
1470         /*
1471          * Point to the leaf entry, use that to point to the data entry.
1472          */
1473         lep = &leaf->ents[index];
1474         db = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
1475         dep = (xfs_dir2_data_entry_t *)
1476               ((char *)data + XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
1477         needscan = needlog = 0;
1478         oldbest = be16_to_cpu(data->hdr.bestfree[0].length);
1479         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1480         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
1481         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1482         /*
1483          * Mark the former data entry unused.
1484          */
1485         xfs_dir2_data_make_free(tp, dbp,
1486                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)data),
1487                 XFS_DIR2_DATA_ENTSIZE(dep->namelen), &needlog, &needscan);
1488         /*
1489          * We just mark the leaf entry stale by putting a null in it.
1490          */
1491         INT_MOD(leaf->hdr.stale, ARCH_CONVERT, +1);
1492         xfs_dir2_leaf_log_header(tp, lbp);
1493         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_NULL_DATAPTR);
1494         xfs_dir2_leaf_log_ents(tp, lbp, index, index);
1495         /*
1496          * Scan the freespace in the data block again if necessary,
1497          * log the data block header if necessary.
1498          */
1499         if (needscan)
1500                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
1501         if (needlog)
1502                 xfs_dir2_data_log_header(tp, dbp);
1503         /*
1504          * If the longest freespace in the data block has changed,
1505          * put the new value in the bests table and log that.
1506          */
1507         if (be16_to_cpu(data->hdr.bestfree[0].length) != oldbest) {
1508                 bestsp[db] = data->hdr.bestfree[0].length;
1509                 xfs_dir2_leaf_log_bests(tp, lbp, db, db);
1510         }
1511         xfs_dir2_data_check(dp, dbp);
1512         /*
1513          * If the data block is now empty then get rid of the data block.
1514          */
1515         if (be16_to_cpu(data->hdr.bestfree[0].length) ==
1516             mp->m_dirblksize - (uint)sizeof(data->hdr)) {
1517                 ASSERT(db != mp->m_dirdatablk);
1518                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1519                         /*
1520                          * Nope, can't get rid of it because it caused
1521                          * allocation of a bmap btree block to do so.
1522                          * Just go on, returning success, leaving the
1523                          * empty block in place.
1524                          */
1525                         if (error == ENOSPC && args->total == 0) {
1526                                 xfs_da_buf_done(dbp);
1527                                 error = 0;
1528                         }
1529                         xfs_dir2_leaf_check(dp, lbp);
1530                         xfs_da_buf_done(lbp);
1531                         return error;
1532                 }
1533                 dbp = NULL;
1534                 /*
1535                  * If this is the last data block then compact the
1536                  * bests table by getting rid of entries.
1537                  */
1538                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1539                         /*
1540                          * Look for the last active entry (i).
1541                          */
1542                         for (i = db - 1; i > 0; i--) {
1543                                 if (be16_to_cpu(bestsp[i]) != NULLDATAOFF)
1544                                         break;
1545                         }
1546                         /*
1547                          * Copy the table down so inactive entries at the
1548                          * end are removed.
1549                          */
1550                         memmove(&bestsp[db - i], bestsp,
1551                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1552                         be32_add(&ltp->bestcount, -(db - i));
1553                         xfs_dir2_leaf_log_tail(tp, lbp);
1554                         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1555                 } else
1556                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1557         }
1558         /*
1559          * If the data block was not the first one, drop it.
1560          */
1561         else if (db != mp->m_dirdatablk && dbp != NULL) {
1562                 xfs_da_buf_done(dbp);
1563                 dbp = NULL;
1564         }
1565         xfs_dir2_leaf_check(dp, lbp);
1566         /*
1567          * See if we can convert to block form.
1568          */
1569         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1570 }
1571
1572 /*
1573  * Replace the inode number in a leaf format directory entry.
1574  */
1575 int                                             /* error */
1576 xfs_dir2_leaf_replace(
1577         xfs_da_args_t           *args)          /* operation arguments */
1578 {
1579         xfs_dabuf_t             *dbp;           /* data block buffer */
1580         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1581         xfs_inode_t             *dp;            /* incore directory inode */
1582         int                     error;          /* error return code */
1583         int                     index;          /* index of leaf entry */
1584         xfs_dabuf_t             *lbp;           /* leaf buffer */
1585         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1586         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1587         xfs_trans_t             *tp;            /* transaction pointer */
1588
1589         xfs_dir2_trace_args("leaf_replace", args);
1590         /*
1591          * Look up the entry.
1592          */
1593         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1594                 return error;
1595         }
1596         dp = args->dp;
1597         leaf = lbp->data;
1598         /*
1599          * Point to the leaf entry, get data address from it.
1600          */
1601         lep = &leaf->ents[index];
1602         /*
1603          * Point to the data entry.
1604          */
1605         dep = (xfs_dir2_data_entry_t *)
1606               ((char *)dbp->data +
1607                XFS_DIR2_DATAPTR_TO_OFF(dp->i_mount, INT_GET(lep->address, ARCH_CONVERT)));
1608         ASSERT(args->inumber != INT_GET(dep->inumber, ARCH_CONVERT));
1609         /*
1610          * Put the new inode number in, log it.
1611          */
1612         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
1613         tp = args->trans;
1614         xfs_dir2_data_log_entry(tp, dbp, dep);
1615         xfs_da_buf_done(dbp);
1616         xfs_dir2_leaf_check(dp, lbp);
1617         xfs_da_brelse(tp, lbp);
1618         return 0;
1619 }
1620
1621 /*
1622  * Return index in the leaf block (lbp) which is either the first
1623  * one with this hash value, or if there are none, the insert point
1624  * for that hash value.
1625  */
1626 int                                             /* index value */
1627 xfs_dir2_leaf_search_hash(
1628         xfs_da_args_t           *args,          /* operation arguments */
1629         xfs_dabuf_t             *lbp)           /* leaf buffer */
1630 {
1631         xfs_dahash_t            hash=0;         /* hash from this entry */
1632         xfs_dahash_t            hashwant;       /* hash value looking for */
1633         int                     high;           /* high leaf index */
1634         int                     low;            /* low leaf index */
1635         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1636         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1637         int                     mid=0;          /* current leaf index */
1638
1639         leaf = lbp->data;
1640 #ifndef __KERNEL__
1641         if (!leaf->hdr.count)
1642                 return 0;
1643 #endif
1644         /*
1645          * Note, the table cannot be empty, so we have to go through the loop.
1646          * Binary search the leaf entries looking for our hash value.
1647          */
1648         for (lep = leaf->ents, low = 0, high = INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1,
1649                 hashwant = args->hashval;
1650              low <= high; ) {
1651                 mid = (low + high) >> 1;
1652                 if ((hash = INT_GET(lep[mid].hashval, ARCH_CONVERT)) == hashwant)
1653                         break;
1654                 if (hash < hashwant)
1655                         low = mid + 1;
1656                 else
1657                         high = mid - 1;
1658         }
1659         /*
1660          * Found one, back up through all the equal hash values.
1661          */
1662         if (hash == hashwant) {
1663                 while (mid > 0 && INT_GET(lep[mid - 1].hashval, ARCH_CONVERT) == hashwant) {
1664                         mid--;
1665                 }
1666         }
1667         /*
1668          * Need to point to an entry higher than ours.
1669          */
1670         else if (hash < hashwant)
1671                 mid++;
1672         return mid;
1673 }
1674
1675 /*
1676  * Trim off a trailing data block.  We know it's empty since the leaf
1677  * freespace table says so.
1678  */
1679 int                                             /* error */
1680 xfs_dir2_leaf_trim_data(
1681         xfs_da_args_t           *args,          /* operation arguments */
1682         xfs_dabuf_t             *lbp,           /* leaf buffer */
1683         xfs_dir2_db_t           db)             /* data block number */
1684 {
1685         __be16                  *bestsp;        /* leaf bests table */
1686 #ifdef DEBUG
1687         xfs_dir2_data_t         *data;          /* data block structure */
1688 #endif
1689         xfs_dabuf_t             *dbp;           /* data block buffer */
1690         xfs_inode_t             *dp;            /* incore directory inode */
1691         int                     error;          /* error return value */
1692         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1693         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1694         xfs_mount_t             *mp;            /* filesystem mount point */
1695         xfs_trans_t             *tp;            /* transaction pointer */
1696
1697         dp = args->dp;
1698         mp = dp->i_mount;
1699         tp = args->trans;
1700         /*
1701          * Read the offending data block.  We need its buffer.
1702          */
1703         if ((error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, db), -1, &dbp,
1704                         XFS_DATA_FORK))) {
1705                 return error;
1706         }
1707 #ifdef DEBUG
1708         data = dbp->data;
1709         ASSERT(be32_to_cpu(data->hdr.magic) == XFS_DIR2_DATA_MAGIC);
1710 #endif
1711         /* this seems to be an error
1712          * data is only valid if DEBUG is defined?
1713          * RMC 09/08/1999
1714          */
1715
1716         leaf = lbp->data;
1717         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1718         ASSERT(be16_to_cpu(data->hdr.bestfree[0].length) ==
1719                mp->m_dirblksize - (uint)sizeof(data->hdr));
1720         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1721         /*
1722          * Get rid of the data block.
1723          */
1724         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1725                 ASSERT(error != ENOSPC);
1726                 xfs_da_brelse(tp, dbp);
1727                 return error;
1728         }
1729         /*
1730          * Eliminate the last bests entry from the table.
1731          */
1732         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
1733         be32_add(&ltp->bestcount, -1);
1734         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1735         xfs_dir2_leaf_log_tail(tp, lbp);
1736         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1737         return 0;
1738 }
1739
1740 /*
1741  * Convert node form directory to leaf form directory.
1742  * The root of the node form dir needs to already be a LEAFN block.
1743  * Just return if we can't do anything.
1744  */
1745 int                                             /* error */
1746 xfs_dir2_node_to_leaf(
1747         xfs_da_state_t          *state)         /* directory operation state */
1748 {
1749         xfs_da_args_t           *args;          /* operation arguments */
1750         xfs_inode_t             *dp;            /* incore directory inode */
1751         int                     error;          /* error return code */
1752         xfs_dabuf_t             *fbp;           /* buffer for freespace block */
1753         xfs_fileoff_t           fo;             /* freespace file offset */
1754         xfs_dir2_free_t         *free;          /* freespace structure */
1755         xfs_dabuf_t             *lbp;           /* buffer for leaf block */
1756         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1757         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1758         xfs_mount_t             *mp;            /* filesystem mount point */
1759         int                     rval;           /* successful free trim? */
1760         xfs_trans_t             *tp;            /* transaction pointer */
1761
1762         /*
1763          * There's more than a leaf level in the btree, so there must
1764          * be multiple leafn blocks.  Give up.
1765          */
1766         if (state->path.active > 1)
1767                 return 0;
1768         args = state->args;
1769         xfs_dir2_trace_args("node_to_leaf", args);
1770         mp = state->mp;
1771         dp = args->dp;
1772         tp = args->trans;
1773         /*
1774          * Get the last offset in the file.
1775          */
1776         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1777                 return error;
1778         }
1779         fo -= mp->m_dirblkfsbs;
1780         /*
1781          * If there are freespace blocks other than the first one,
1782          * take this opportunity to remove trailing empty freespace blocks
1783          * that may have been left behind during no-space-reservation
1784          * operations.
1785          */
1786         while (fo > mp->m_dirfreeblk) {
1787                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1788                         return error;
1789                 }
1790                 if (rval)
1791                         fo -= mp->m_dirblkfsbs;
1792                 else
1793                         return 0;
1794         }
1795         /*
1796          * Now find the block just before the freespace block.
1797          */
1798         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1799                 return error;
1800         }
1801         /*
1802          * If it's not the single leaf block, give up.
1803          */
1804         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1805                 return 0;
1806         lbp = state->path.blk[0].bp;
1807         leaf = lbp->data;
1808         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1809         /*
1810          * Read the freespace block.
1811          */
1812         if ((error = xfs_da_read_buf(tp, dp, mp->m_dirfreeblk, -1, &fbp,
1813                         XFS_DATA_FORK))) {
1814                 return error;
1815         }
1816         free = fbp->data;
1817         ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
1818         ASSERT(!free->hdr.firstdb);
1819         /*
1820          * Now see if the leafn and free data will fit in a leaf1.
1821          * If not, release the buffer and give up.
1822          */
1823         if ((uint)sizeof(leaf->hdr) +
1824             (INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT)) * (uint)sizeof(leaf->ents[0]) +
1825             be32_to_cpu(free->hdr.nvalid) * (uint)sizeof(leaf->bests[0]) +
1826             (uint)sizeof(leaf->tail) >
1827             mp->m_dirblksize) {
1828                 xfs_da_brelse(tp, fbp);
1829                 return 0;
1830         }
1831         /*
1832          * If the leaf has any stale entries in it, compress them out.
1833          * The compact routine will log the header.
1834          */
1835         if (INT_GET(leaf->hdr.stale, ARCH_CONVERT))
1836                 xfs_dir2_leaf_compact(args, lbp);
1837         else
1838                 xfs_dir2_leaf_log_header(tp, lbp);
1839         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, XFS_DIR2_LEAF1_MAGIC);
1840         /*
1841          * Set up the leaf tail from the freespace block.
1842          */
1843         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1844         ltp->bestcount = free->hdr.nvalid;
1845         /*
1846          * Set up the leaf bests table.
1847          */
1848         memcpy(XFS_DIR2_LEAF_BESTS_P(ltp), free->bests,
1849                 be32_to_cpu(ltp->bestcount) * sizeof(leaf->bests[0]));
1850         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1851         xfs_dir2_leaf_log_tail(tp, lbp);
1852         xfs_dir2_leaf_check(dp, lbp);
1853         /*
1854          * Get rid of the freespace block.
1855          */
1856         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1857         if (error) {
1858                 /*
1859                  * This can't fail here because it can only happen when
1860                  * punching out the middle of an extent, and this is an
1861                  * isolated block.
1862                  */
1863                 ASSERT(error != ENOSPC);
1864                 return error;
1865         }
1866         fbp = NULL;
1867         /*
1868          * Now see if we can convert the single-leaf directory
1869          * down to a block form directory.
1870          * This routine always kills the dabuf for the leaf, so
1871          * eliminate it from the path.
1872          */
1873         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1874         state->path.blk[0].bp = NULL;
1875         return error;
1876 }