fs/xfs/xfs_dir2_leaf.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3  * Copyright (c) 2013 Red Hat, Inc.
   4  * All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it would be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write the Free Software Foundation,
  17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 #include "xfs.h"
  20 #include "xfs_fs.h"
  21 #include "xfs_format.h"
  22 #include "xfs_log_format.h"
  23 #include "xfs_trans_resv.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_ag.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_da_format.h"
  28 #include "xfs_da_btree.h"
  29 #include "xfs_inode.h"
  30 #include "xfs_bmap.h"
  31 #include "xfs_dir2.h"
  32 #include "xfs_dir2_priv.h"
  33 #include "xfs_error.h"
  34 #include "xfs_trace.h"
  35 #include "xfs_trans.h"
  36 #include "xfs_buf_item.h"
  37 #include "xfs_cksum.h"
  38
  39 /*
  40  * Local function declarations.
  41  */
  42 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
  43                                     int *indexp, struct xfs_buf **dbpp);
  44 static void xfs_dir3_leaf_log_bests(struct xfs_trans *tp, struct xfs_buf *bp,
  45                                     int first, int last);
  46 static void xfs_dir3_leaf_log_tail(struct xfs_trans *tp, struct xfs_buf *bp);
  47
  48 /*
  49  * Check the internal consistency of a leaf1 block.
  50  * Pop an assert if something is wrong.
  51  */
  52 #ifdef DEBUG
  53 #define xfs_dir3_leaf_check(dp, bp) \
  54 do { \
  55         if (!xfs_dir3_leaf1_check((dp), (bp))) \
  56                 ASSERT(0); \
  57 } while (0);
  58
  59 STATIC bool
  60 xfs_dir3_leaf1_check(
  61         struct xfs_inode        *dp,
  62         struct xfs_buf          *bp)
  63 {
  64         struct xfs_dir2_leaf    *leaf = bp->b_addr;
  65         struct xfs_dir3_icleaf_hdr leafhdr;
  66
  67         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
  68
  69         if (leafhdr.magic == XFS_DIR3_LEAF1_MAGIC) {
  70                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
  71                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
  72                         return false;
  73         } else if (leafhdr.magic != XFS_DIR2_LEAF1_MAGIC)
  74                 return false;
  75
  76         return xfs_dir3_leaf_check_int(dp->i_mount, dp, &leafhdr, leaf);
  77 }
  78 #else
  79 #define xfs_dir3_leaf_check(dp, bp)
  80 #endif
  81
  82 bool
  83 xfs_dir3_leaf_check_int(
  84         struct xfs_mount        *mp,
  85         struct xfs_inode        *dp,
  86         struct xfs_dir3_icleaf_hdr *hdr,
  87         struct xfs_dir2_leaf    *leaf)
  88 {
  89         struct xfs_dir2_leaf_entry *ents;
  90         xfs_dir2_leaf_tail_t    *ltp;
  91         int                     stale;
  92         int                     i;
  93         const struct xfs_dir_ops *ops;
  94         struct xfs_dir3_icleaf_hdr leafhdr;
  95
  96         /*
  97          * we can be passed a null dp here from a verifier, so we need to go the
  98          * hard way to get them.
  99          */
 100         ops = xfs_dir_get_ops(mp, dp);
 101
 102         if (!hdr) {
 103                 ops->leaf_hdr_from_disk(&leafhdr, leaf);
 104                 hdr = &leafhdr;
 105         }
 106
 107         ents = ops->leaf_ents_p(leaf);
 108         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 109
 110         /*
 111          * XXX (dgc): This value is not restrictive enough.
 112          * Should factor in the size of the bests table as well.
 113          * We can deduce a value for that from di_size.
 114          */
 115         if (hdr->count > ops->leaf_max_ents(mp))
 116                 return false;
 117
 118         /* Leaves and bests don't overlap in leaf format. */
 119         if ((hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
 120              hdr->magic == XFS_DIR3_LEAF1_MAGIC) &&
 121             (char *)&ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
 122                 return false;
 123
 124         /* Check hash value order, count stale entries.  */
 125         for (i = stale = 0; i < hdr->count; i++) {
 126                 if (i + 1 < hdr->count) {
 127                         if (be32_to_cpu(ents[i].hashval) >
 128                                         be32_to_cpu(ents[i + 1].hashval))
 129                                 return false;
 130                 }
 131                 if (ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 132                         stale++;
 133         }
 134         if (hdr->stale != stale)
 135                 return false;
 136         return true;
 137 }
 138
 139 /*
 140  * We verify the magic numbers before decoding the leaf header so that on debug
 141  * kernels we don't get assertion failures in xfs_dir3_leaf_hdr_from_disk() due
 142  * to incorrect magic numbers.
 143  */
 144 static bool
 145 xfs_dir3_leaf_verify(
 146         struct xfs_buf          *bp,
 147         __uint16_t              magic)
 148 {
 149         struct xfs_mount        *mp = bp->b_target->bt_mount;
 150         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 151
 152         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 153
 154         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 155                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 156                 __uint16_t              magic3;
 157
 158                 magic3 = (magic == XFS_DIR2_LEAF1_MAGIC) ? XFS_DIR3_LEAF1_MAGIC
 159                                                          : XFS_DIR3_LEAFN_MAGIC;
 160
 161                 if (leaf3->info.hdr.magic != cpu_to_be16(magic3))
 162                         return false;
 163                 if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_uuid))
 164                         return false;
 165                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
 166                         return false;
 167         } else {
 168                 if (leaf->hdr.info.magic != cpu_to_be16(magic))
 169                         return false;
 170         }
 171
 172         return xfs_dir3_leaf_check_int(mp, NULL, NULL, leaf);
 173 }
 174
 175 static void
 176 __read_verify(
 177         struct xfs_buf  *bp,
 178         __uint16_t      magic)
 179 {
 180         struct xfs_mount        *mp = bp->b_target->bt_mount;
 181
 182         if (xfs_sb_version_hascrc(&mp->m_sb) &&
 183              !xfs_buf_verify_cksum(bp, XFS_DIR3_LEAF_CRC_OFF))
 184                 xfs_buf_ioerror(bp, EFSBADCRC);
 185         else if (!xfs_dir3_leaf_verify(bp, magic))
 186                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 187
 188         if (bp->b_error)
 189                 xfs_verifier_error(bp);
 190 }
 191
 192 static void
 193 __write_verify(
 194         struct xfs_buf  *bp,
 195         __uint16_t      magic)
 196 {
 197         struct xfs_mount        *mp = bp->b_target->bt_mount;
 198         struct xfs_buf_log_item *bip = bp->b_fspriv;
 199         struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 200
 201         if (!xfs_dir3_leaf_verify(bp, magic)) {
 202                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 203                 xfs_verifier_error(bp);
 204                 return;
 205         }
 206
 207         if (!xfs_sb_version_hascrc(&mp->m_sb))
 208                 return;
 209
 210         if (bip)
 211                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 212
 213         xfs_buf_update_cksum(bp, XFS_DIR3_LEAF_CRC_OFF);
 214 }
 215
 216 static void
 217 xfs_dir3_leaf1_read_verify(
 218         struct xfs_buf  *bp)
 219 {
 220         __read_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 221 }
 222
 223 static void
 224 xfs_dir3_leaf1_write_verify(
 225         struct xfs_buf  *bp)
 226 {
 227         __write_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 228 }
 229
 230 static void
 231 xfs_dir3_leafn_read_verify(
 232         struct xfs_buf  *bp)
 233 {
 234         __read_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 235 }
 236
 237 static void
 238 xfs_dir3_leafn_write_verify(
 239         struct xfs_buf  *bp)
 240 {
 241         __write_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 242 }
 243
 244 const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 245         .verify_read = xfs_dir3_leaf1_read_verify,
 246         .verify_write = xfs_dir3_leaf1_write_verify,
 247 };
 248
 249 const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 250         .verify_read = xfs_dir3_leafn_read_verify,
 251         .verify_write = xfs_dir3_leafn_write_verify,
 252 };
 253
 254 static int
 255 xfs_dir3_leaf_read(
 256         struct xfs_trans        *tp,
 257         struct xfs_inode        *dp,
 258         xfs_dablk_t             fbno,
 259         xfs_daddr_t             mappedbno,
 260         struct xfs_buf          **bpp)
 261 {
 262         int                     err;
 263
 264         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 265                                 XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
 266         if (!err && tp)
 267                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 268         return err;
 269 }
 270
 271 int
 272 xfs_dir3_leafn_read(
 273         struct xfs_trans        *tp,
 274         struct xfs_inode        *dp,
 275         xfs_dablk_t             fbno,
 276         xfs_daddr_t             mappedbno,
 277         struct xfs_buf          **bpp)
 278 {
 279         int                     err;
 280
 281         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 282                                 XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
 283         if (!err && tp)
 284                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 285         return err;
 286 }
 287
 288 /*
 289  * Initialize a new leaf block, leaf1 or leafn magic accepted.
 290  */
 291 static void
 292 xfs_dir3_leaf_init(
 293         struct xfs_mount        *mp,
 294         struct xfs_trans        *tp,
 295         struct xfs_buf          *bp,
 296         xfs_ino_t               owner,
 297         __uint16_t              type)
 298 {
 299         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 300
 301         ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 302
 303         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 304                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 305
 306                 memset(leaf3, 0, sizeof(*leaf3));
 307
 308                 leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 309                                          ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 310                                          : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 311                 leaf3->info.blkno = cpu_to_be64(bp->b_bn);
 312                 leaf3->info.owner = cpu_to_be64(owner);
 313                 uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_uuid);
 314         } else {
 315                 memset(leaf, 0, sizeof(*leaf));
 316                 leaf->hdr.info.magic = cpu_to_be16(type);
 317         }
 318
 319         /*
 320          * If it's a leaf-format directory initialize the tail.
 321          * Caller is responsible for initialising the bests table.
 322          */
 323         if (type == XFS_DIR2_LEAF1_MAGIC) {
 324                 struct xfs_dir2_leaf_tail *ltp;
 325
 326                 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 327                 ltp->bestcount = 0;
 328                 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 329                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 330         } else {
 331                 bp->b_ops = &xfs_dir3_leafn_buf_ops;
 332                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 333         }
 334 }
 335
 336 int
 337 xfs_dir3_leaf_get_buf(
 338         xfs_da_args_t           *args,
 339         xfs_dir2_db_t           bno,
 340         struct xfs_buf          **bpp,
 341         __uint16_t              magic)
 342 {
 343         struct xfs_inode        *dp = args->dp;
 344         struct xfs_trans        *tp = args->trans;
 345         struct xfs_mount        *mp = dp->i_mount;
 346         struct xfs_buf          *bp;
 347         int                     error;
 348
 349         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 350         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
 351                bno < XFS_DIR2_FREE_FIRSTDB(mp));
 352
 353         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
 354                                XFS_DATA_FORK);
 355         if (error)
 356                 return error;
 357
 358         xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
 359         xfs_dir3_leaf_log_header(tp, dp, bp);
 360         if (magic == XFS_DIR2_LEAF1_MAGIC)
 361                 xfs_dir3_leaf_log_tail(tp, bp);
 362         *bpp = bp;
 363         return 0;
 364 }
 365
 366 /*
 367  * Convert a block form directory to a leaf form directory.
 368  */
 369 int                                             /* error */
 370 xfs_dir2_block_to_leaf(
 371         xfs_da_args_t           *args,          /* operation arguments */
 372         struct xfs_buf          *dbp)           /* input block's buffer */
 373 {
 374         __be16                  *bestsp;        /* leaf's bestsp entries */
 375         xfs_dablk_t             blkno;          /* leaf block's bno */
 376         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 377         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
 378         xfs_dir2_block_tail_t   *btp;           /* block's tail */
 379         xfs_inode_t             *dp;            /* incore directory inode */
 380         int                     error;          /* error return code */
 381         struct xfs_buf          *lbp;           /* leaf block's buffer */
 382         xfs_dir2_db_t           ldb;            /* leaf block's bno */
 383         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 384         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
 385         xfs_mount_t             *mp;            /* filesystem mount point */
 386         int                     needlog;        /* need to log block header */
 387         int                     needscan;       /* need to rescan bestfree */
 388         xfs_trans_t             *tp;            /* transaction pointer */
 389         struct xfs_dir2_data_free *bf;
 390         struct xfs_dir2_leaf_entry *ents;
 391         struct xfs_dir3_icleaf_hdr leafhdr;
 392
 393         trace_xfs_dir2_block_to_leaf(args);
 394
 395         dp = args->dp;
 396         mp = dp->i_mount;
 397         tp = args->trans;
 398         /*
 399          * Add the leaf block to the inode.
 400          * This interface will only put blocks in the leaf/node range.
 401          * Since that's empty now, we'll get the root (block 0 in range).
 402          */
 403         if ((error = xfs_da_grow_inode(args, &blkno))) {
 404                 return error;
 405         }
 406         ldb = xfs_dir2_da_to_db(mp, blkno);
 407         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
 408         /*
 409          * Initialize the leaf block, get a buffer for it.
 410          */
 411         error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 412         if (error)
 413                 return error;
 414
 415         leaf = lbp->b_addr;
 416         hdr = dbp->b_addr;
 417         xfs_dir3_data_check(dp, dbp);
 418         btp = xfs_dir2_block_tail_p(mp, hdr);
 419         blp = xfs_dir2_block_leaf_p(btp);
 420         bf = dp->d_ops->data_bestfree_p(hdr);
 421         ents = dp->d_ops->leaf_ents_p(leaf);
 422
 423         /*
 424          * Set the counts in the leaf header.
 425          */
 426         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 427         leafhdr.count = be32_to_cpu(btp->count);
 428         leafhdr.stale = be32_to_cpu(btp->stale);
 429         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 430         xfs_dir3_leaf_log_header(tp, dp, lbp);
 431
 432         /*
 433          * Could compact these but I think we always do the conversion
 434          * after squeezing out stale entries.
 435          */
 436         memcpy(ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
 437         xfs_dir3_leaf_log_ents(tp, dp, lbp, 0, leafhdr.count - 1);
 438         needscan = 0;
 439         needlog = 1;
 440         /*
 441          * Make the space formerly occupied by the leaf entries and block
 442          * tail be free.
 443          */
 444         xfs_dir2_data_make_free(tp, dp, dbp,
 445                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 446                 (xfs_dir2_data_aoff_t)((char *)hdr + mp->m_dirblksize -
 447                                        (char *)blp),
 448                 &needlog, &needscan);
 449         /*
 450          * Fix up the block header, make it a data block.
 451          */
 452         dbp->b_ops = &xfs_dir3_data_buf_ops;
 453         xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 454         if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 455                 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 456         else
 457                 hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 458
 459         if (needscan)
 460                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 461         /*
 462          * Set up leaf tail and bests table.
 463          */
 464         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 465         ltp->bestcount = cpu_to_be32(1);
 466         bestsp = xfs_dir2_leaf_bests_p(ltp);
 467         bestsp[0] =  bf[0].length;
 468         /*
 469          * Log the data header and leaf bests table.
 470          */
 471         if (needlog)
 472                 xfs_dir2_data_log_header(tp, dp, dbp);
 473         xfs_dir3_leaf_check(dp, lbp);
 474         xfs_dir3_data_check(dp, dbp);
 475         xfs_dir3_leaf_log_bests(tp, lbp, 0, 0);
 476         return 0;
 477 }
 478
 479 STATIC void
 480 xfs_dir3_leaf_find_stale(
 481         struct xfs_dir3_icleaf_hdr *leafhdr,
 482         struct xfs_dir2_leaf_entry *ents,
 483         int                     index,
 484         int                     *lowstale,
 485         int                     *highstale)
 486 {
 487         /*
 488          * Find the first stale entry before our index, if any.
 489          */
 490         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 491                 if (ents[*lowstale].address ==
 492                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 493                         break;
 494         }
 495
 496         /*
 497          * Find the first stale entry at or after our index, if any.
 498          * Stop if the result would require moving more entries than using
 499          * lowstale.
 500          */
 501         for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 502                 if (ents[*highstale].address ==
 503                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 504                         break;
 505                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 506                         break;
 507         }
 508 }
 509
 510 struct xfs_dir2_leaf_entry *
 511 xfs_dir3_leaf_find_entry(
 512         struct xfs_dir3_icleaf_hdr *leafhdr,
 513         struct xfs_dir2_leaf_entry *ents,
 514         int                     index,          /* leaf table position */
 515         int                     compact,        /* need to compact leaves */
 516         int                     lowstale,       /* index of prev stale leaf */
 517         int                     highstale,      /* index of next stale leaf */
 518         int                     *lfloglow,      /* low leaf logging index */
 519         int                     *lfloghigh)     /* high leaf logging index */
 520 {
 521         if (!leafhdr->stale) {
 522                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 523
 524                 /*
 525                  * Now we need to make room to insert the leaf entry.
 526                  *
 527                  * If there are no stale entries, just insert a hole at index.
 528                  */
 529                 lep = &ents[index];
 530                 if (index < leafhdr->count)
 531                         memmove(lep + 1, lep,
 532                                 (leafhdr->count - index) * sizeof(*lep));
 533
 534                 /*
 535                  * Record low and high logging indices for the leaf.
 536                  */
 537                 *lfloglow = index;
 538                 *lfloghigh = leafhdr->count++;
 539                 return lep;
 540         }
 541
 542         /*
 543          * There are stale entries.
 544          *
 545          * We will use one of them for the new entry.  It's probably not at
 546          * the right location, so we'll have to shift some up or down first.
 547          *
 548          * If we didn't compact before, we need to find the nearest stale
 549          * entries before and after our insertion point.
 550          */
 551         if (compact == 0)
 552                 xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 553                                          &lowstale, &highstale);
 554
 555         /*
 556          * If the low one is better, use it.
 557          */
 558         if (lowstale >= 0 &&
 559             (highstale == leafhdr->count ||
 560              index - lowstale - 1 < highstale - index)) {
 561                 ASSERT(index - lowstale - 1 >= 0);
 562                 ASSERT(ents[lowstale].address ==
 563                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 564
 565                 /*
 566                  * Copy entries up to cover the stale entry and make room
 567                  * for the new entry.
 568                  */
 569                 if (index - lowstale - 1 > 0) {
 570                         memmove(&ents[lowstale], &ents[lowstale + 1],
 571                                 (index - lowstale - 1) *
 572                                         sizeof(xfs_dir2_leaf_entry_t));
 573                 }
 574                 *lfloglow = MIN(lowstale, *lfloglow);
 575                 *lfloghigh = MAX(index - 1, *lfloghigh);
 576                 leafhdr->stale--;
 577                 return &ents[index - 1];
 578         }
 579
 580         /*
 581          * The high one is better, so use that one.
 582          */
 583         ASSERT(highstale - index >= 0);
 584         ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 585
 586         /*
 587          * Copy entries down to cover the stale entry and make room for the
 588          * new entry.
 589          */
 590         if (highstale - index > 0) {
 591                 memmove(&ents[index + 1], &ents[index],
 592                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 593         }
 594         *lfloglow = MIN(index, *lfloglow);
 595         *lfloghigh = MAX(highstale, *lfloghigh);
 596         leafhdr->stale--;
 597         return &ents[index];
 598 }
 599
 600 /*
 601  * Add an entry to a leaf form directory.
 602  */
 603 int                                             /* error */
 604 xfs_dir2_leaf_addname(
 605         xfs_da_args_t           *args)          /* operation arguments */
 606 {
 607         __be16                  *bestsp;        /* freespace table in leaf */
 608         int                     compact;        /* need to compact leaves */
 609         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 610         struct xfs_buf          *dbp;           /* data block buffer */
 611         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 612         xfs_inode_t             *dp;            /* incore directory inode */
 613         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 614         int                     error;          /* error return value */
 615         int                     grown;          /* allocated new data block */
 616         int                     highstale;      /* index of next stale leaf */
 617         int                     i;              /* temporary, index */
 618         int                     index;          /* leaf table position */
 619         struct xfs_buf          *lbp;           /* leaf's buffer */
 620         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 621         int                     length;         /* length of new entry */
 622         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 623         int                     lfloglow;       /* low leaf logging index */
 624         int                     lfloghigh;      /* high leaf logging index */
 625         int                     lowstale;       /* index of prev stale leaf */
 626         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 627         xfs_mount_t             *mp;            /* filesystem mount point */
 628         int                     needbytes;      /* leaf block bytes needed */
 629         int                     needlog;        /* need to log data header */
 630         int                     needscan;       /* need to rescan data free */
 631         __be16                  *tagp;          /* end of data entry */
 632         xfs_trans_t             *tp;            /* transaction pointer */
 633         xfs_dir2_db_t           use_block;      /* data block number */
 634         struct xfs_dir2_data_free *bf;          /* bestfree table */
 635         struct xfs_dir2_leaf_entry *ents;
 636         struct xfs_dir3_icleaf_hdr leafhdr;
 637
 638         trace_xfs_dir2_leaf_addname(args);
 639
 640         dp = args->dp;
 641         tp = args->trans;
 642         mp = dp->i_mount;
 643
 644         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
 645         if (error)
 646                 return error;
 647
 648         /*
 649          * Look up the entry by hash value and name.
 650          * We know it's not there, our caller has already done a lookup.
 651          * So the index is of the entry to insert in front of.
 652          * But if there are dup hash values the index is of the first of those.
 653          */
 654         index = xfs_dir2_leaf_search_hash(args, lbp);
 655         leaf = lbp->b_addr;
 656         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 657         ents = dp->d_ops->leaf_ents_p(leaf);
 658         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 659         bestsp = xfs_dir2_leaf_bests_p(ltp);
 660         length = dp->d_ops->data_entsize(args->namelen);
 661
 662         /*
 663          * See if there are any entries with the same hash value
 664          * and space in their block for the new entry.
 665          * This is good because it puts multiple same-hash value entries
 666          * in a data block, improving the lookup of those entries.
 667          */
 668         for (use_block = -1, lep = &ents[index];
 669              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 670              index++, lep++) {
 671                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 672                         continue;
 673                 i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 674                 ASSERT(i < be32_to_cpu(ltp->bestcount));
 675                 ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 676                 if (be16_to_cpu(bestsp[i]) >= length) {
 677                         use_block = i;
 678                         break;
 679                 }
 680         }
 681         /*
 682          * Didn't find a block yet, linear search all the data blocks.
 683          */
 684         if (use_block == -1) {
 685                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 686                         /*
 687                          * Remember a block we see that's missing.
 688                          */
 689                         if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 690                             use_block == -1)
 691                                 use_block = i;
 692                         else if (be16_to_cpu(bestsp[i]) >= length) {
 693                                 use_block = i;
 694                                 break;
 695                         }
 696                 }
 697         }
 698         /*
 699          * How many bytes do we need in the leaf block?
 700          */
 701         needbytes = 0;
 702         if (!leafhdr.stale)
 703                 needbytes += sizeof(xfs_dir2_leaf_entry_t);
 704         if (use_block == -1)
 705                 needbytes += sizeof(xfs_dir2_data_off_t);
 706
 707         /*
 708          * Now kill use_block if it refers to a missing block, so we
 709          * can use it as an indication of allocation needed.
 710          */
 711         if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 712                 use_block = -1;
 713         /*
 714          * If we don't have enough free bytes but we can make enough
 715          * by compacting out stale entries, we'll do that.
 716          */
 717         if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
 718             leafhdr.stale > 1)
 719                 compact = 1;
 720
 721         /*
 722          * Otherwise if we don't have enough free bytes we need to
 723          * convert to node form.
 724          */
 725         else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
 726                 /*
 727                  * Just checking or no space reservation, give up.
 728                  */
 729                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 730                                                         args->total == 0) {
 731                         xfs_trans_brelse(tp, lbp);
 732                         return XFS_ERROR(ENOSPC);
 733                 }
 734                 /*
 735                  * Convert to node form.
 736                  */
 737                 error = xfs_dir2_leaf_to_node(args, lbp);
 738                 if (error)
 739                         return error;
 740                 /*
 741                  * Then add the new entry.
 742                  */
 743                 return xfs_dir2_node_addname(args);
 744         }
 745         /*
 746          * Otherwise it will fit without compaction.
 747          */
 748         else
 749                 compact = 0;
 750         /*
 751          * If just checking, then it will fit unless we needed to allocate
 752          * a new data block.
 753          */
 754         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 755                 xfs_trans_brelse(tp, lbp);
 756                 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
 757         }
 758         /*
 759          * If no allocations are allowed, return now before we've
 760          * changed anything.
 761          */
 762         if (args->total == 0 && use_block == -1) {
 763                 xfs_trans_brelse(tp, lbp);
 764                 return XFS_ERROR(ENOSPC);
 765         }
 766         /*
 767          * Need to compact the leaf entries, removing stale ones.
 768          * Leave one stale entry behind - the one closest to our
 769          * insertion index - and we'll shift that one to our insertion
 770          * point later.
 771          */
 772         if (compact) {
 773                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 774                         &highstale, &lfloglow, &lfloghigh);
 775         }
 776         /*
 777          * There are stale entries, so we'll need log-low and log-high
 778          * impossibly bad values later.
 779          */
 780         else if (leafhdr.stale) {
 781                 lfloglow = leafhdr.count;
 782                 lfloghigh = -1;
 783         }
 784         /*
 785          * If there was no data block space found, we need to allocate
 786          * a new one.
 787          */
 788         if (use_block == -1) {
 789                 /*
 790                  * Add the new data block.
 791                  */
 792                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 793                                 &use_block))) {
 794                         xfs_trans_brelse(tp, lbp);
 795                         return error;
 796                 }
 797                 /*
 798                  * Initialize the block.
 799                  */
 800                 if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
 801                         xfs_trans_brelse(tp, lbp);
 802                         return error;
 803                 }
 804                 /*
 805                  * If we're adding a new data block on the end we need to
 806                  * extend the bests table.  Copy it up one entry.
 807                  */
 808                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
 809                         bestsp--;
 810                         memmove(&bestsp[0], &bestsp[1],
 811                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 812                         be32_add_cpu(&ltp->bestcount, 1);
 813                         xfs_dir3_leaf_log_tail(tp, lbp);
 814                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
 815                 }
 816                 /*
 817                  * If we're filling in a previously empty block just log it.
 818                  */
 819                 else
 820                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 821                 hdr = dbp->b_addr;
 822                 bf = dp->d_ops->data_bestfree_p(hdr);
 823                 bestsp[use_block] = bf[0].length;
 824                 grown = 1;
 825         } else {
 826                 /*
 827                  * Already had space in some data block.
 828                  * Just read that one in.
 829                  */
 830                 error = xfs_dir3_data_read(tp, dp,
 831                                            xfs_dir2_db_to_da(mp, use_block),
 832                                            -1, &dbp);
 833                 if (error) {
 834                         xfs_trans_brelse(tp, lbp);
 835                         return error;
 836                 }
 837                 hdr = dbp->b_addr;
 838                 bf = dp->d_ops->data_bestfree_p(hdr);
 839                 grown = 0;
 840         }
 841         /*
 842          * Point to the biggest freespace in our data block.
 843          */
 844         dup = (xfs_dir2_data_unused_t *)
 845               ((char *)hdr + be16_to_cpu(bf[0].offset));
 846         ASSERT(be16_to_cpu(dup->length) >= length);
 847         needscan = needlog = 0;
 848         /*
 849          * Mark the initial part of our freespace in use for the new entry.
 850          */
 851         xfs_dir2_data_use_free(tp, dp, dbp, dup,
 852                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
 853                 &needlog, &needscan);
 854         /*
 855          * Initialize our new entry (at last).
 856          */
 857         dep = (xfs_dir2_data_entry_t *)dup;
 858         dep->inumber = cpu_to_be64(args->inumber);
 859         dep->namelen = args->namelen;
 860         memcpy(dep->name, args->name, dep->namelen);
 861         dp->d_ops->data_put_ftype(dep, args->filetype);
 862         tagp = dp->d_ops->data_entry_tag_p(dep);
 863         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 864         /*
 865          * Need to scan fix up the bestfree table.
 866          */
 867         if (needscan)
 868                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 869         /*
 870          * Need to log the data block's header.
 871          */
 872         if (needlog)
 873                 xfs_dir2_data_log_header(tp, dp, dbp);
 874         xfs_dir2_data_log_entry(tp, dp, dbp, dep);
 875         /*
 876          * If the bests table needs to be changed, do it.
 877          * Log the change unless we've already done that.
 878          */
 879         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
 880                 bestsp[use_block] = bf[0].length;
 881                 if (!grown)
 882                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 883         }
 884
 885         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 886                                        highstale, &lfloglow, &lfloghigh);
 887
 888         /*
 889          * Fill in the new leaf entry.
 890          */
 891         lep->hashval = cpu_to_be32(args->hashval);
 892         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
 893                                 be16_to_cpu(*tagp)));
 894         /*
 895          * Log the leaf fields and give up the buffers.
 896          */
 897         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 898         xfs_dir3_leaf_log_header(tp, dp, lbp);
 899         xfs_dir3_leaf_log_ents(tp, dp, lbp, lfloglow, lfloghigh);
 900         xfs_dir3_leaf_check(dp, lbp);
 901         xfs_dir3_data_check(dp, dbp);
 902         return 0;
 903 }
 904
 905 /*
 906  * Compact out any stale entries in the leaf.
 907  * Log the header and changed leaf entries, if any.
 908  */
 909 void
 910 xfs_dir3_leaf_compact(
 911         xfs_da_args_t   *args,          /* operation arguments */
 912         struct xfs_dir3_icleaf_hdr *leafhdr,
 913         struct xfs_buf  *bp)            /* leaf buffer */
 914 {
 915         int             from;           /* source leaf index */
 916         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 917         int             loglow;         /* first leaf entry to log */
 918         int             to;             /* target leaf index */
 919         struct xfs_dir2_leaf_entry *ents;
 920         struct xfs_inode *dp = args->dp;
 921
 922         leaf = bp->b_addr;
 923         if (!leafhdr->stale)
 924                 return;
 925
 926         /*
 927          * Compress out the stale entries in place.
 928          */
 929         ents = dp->d_ops->leaf_ents_p(leaf);
 930         for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 931                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 932                         continue;
 933                 /*
 934                  * Only actually copy the entries that are different.
 935                  */
 936                 if (from > to) {
 937                         if (loglow == -1)
 938                                 loglow = to;
 939                         ents[to] = ents[from];
 940                 }
 941                 to++;
 942         }
 943         /*
 944          * Update and log the header, log the leaf entries.
 945          */
 946         ASSERT(leafhdr->stale == from - to);
 947         leafhdr->count -= leafhdr->stale;
 948         leafhdr->stale = 0;
 949
 950         dp->d_ops->leaf_hdr_to_disk(leaf, leafhdr);
 951         xfs_dir3_leaf_log_header(args->trans, dp, bp);
 952         if (loglow != -1)
 953                 xfs_dir3_leaf_log_ents(args->trans, dp, bp, loglow, to - 1);
 954 }
 955
 956 /*
 957  * Compact the leaf entries, removing stale ones.
 958  * Leave one stale entry behind - the one closest to our
 959  * insertion index - and the caller will shift that one to our insertion
 960  * point later.
 961  * Return new insertion index, where the remaining stale entry is,
 962  * and leaf logging indices.
 963  */
 964 void
 965 xfs_dir3_leaf_compact_x1(
 966         struct xfs_dir3_icleaf_hdr *leafhdr,
 967         struct xfs_dir2_leaf_entry *ents,
 968         int             *indexp,        /* insertion index */
 969         int             *lowstalep,     /* out: stale entry before us */
 970         int             *highstalep,    /* out: stale entry after us */
 971         int             *lowlogp,       /* out: low log index */
 972         int             *highlogp)      /* out: high log index */
 973 {
 974         int             from;           /* source copy index */
 975         int             highstale;      /* stale entry at/after index */
 976         int             index;          /* insertion index */
 977         int             keepstale;      /* source index of kept stale */
 978         int             lowstale;       /* stale entry before index */
 979         int             newindex=0;     /* new insertion index */
 980         int             to;             /* destination copy index */
 981
 982         ASSERT(leafhdr->stale > 1);
 983         index = *indexp;
 984
 985         xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
 986
 987         /*
 988          * Pick the better of lowstale and highstale.
 989          */
 990         if (lowstale >= 0 &&
 991             (highstale == leafhdr->count ||
 992              index - lowstale <= highstale - index))
 993                 keepstale = lowstale;
 994         else
 995                 keepstale = highstale;
 996         /*
 997          * Copy the entries in place, removing all the stale entries
 998          * except keepstale.
 999          */
1000         for (from = to = 0; from < leafhdr->count; from++) {
1001                 /*
1002                  * Notice the new value of index.
1003                  */
1004                 if (index == from)
1005                         newindex = to;
1006                 if (from != keepstale &&
1007                     ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1008                         if (from == to)
1009                                 *lowlogp = to;
1010                         continue;
1011                 }
1012                 /*
1013                  * Record the new keepstale value for the insertion.
1014                  */
1015                 if (from == keepstale)
1016                         lowstale = highstale = to;
1017                 /*
1018                  * Copy only the entries that have moved.
1019                  */
1020                 if (from > to)
1021                         ents[to] = ents[from];
1022                 to++;
1023         }
1024         ASSERT(from > to);
1025         /*
1026          * If the insertion point was past the last entry,
1027          * set the new insertion point accordingly.
1028          */
1029         if (index == from)
1030                 newindex = to;
1031         *indexp = newindex;
1032         /*
1033          * Adjust the leaf header values.
1034          */
1035         leafhdr->count -= from - to;
1036         leafhdr->stale = 1;
1037         /*
1038          * Remember the low/high stale value only in the "right"
1039          * direction.
1040          */
1041         if (lowstale >= newindex)
1042                 lowstale = -1;
1043         else
1044                 highstale = leafhdr->count;
1045         *highlogp = leafhdr->count - 1;
1046         *lowstalep = lowstale;
1047         *highstalep = highstale;
1048 }
1049
1050 /*
1051  * Log the bests entries indicated from a leaf1 block.
1052  */
1053 static void
1054 xfs_dir3_leaf_log_bests(
1055         xfs_trans_t             *tp,            /* transaction pointer */
1056         struct xfs_buf          *bp,            /* leaf buffer */
1057         int                     first,          /* first entry to log */
1058         int                     last)           /* last entry to log */
1059 {
1060         __be16                  *firstb;        /* pointer to first entry */
1061         __be16                  *lastb;         /* pointer to last entry */
1062         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1063         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1064
1065         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1066                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1067
1068         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1069         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1070         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1071         xfs_trans_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1072                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1073 }
1074
1075 /*
1076  * Log the leaf entries indicated from a leaf1 or leafn block.
1077  */
1078 void
1079 xfs_dir3_leaf_log_ents(
1080         struct xfs_trans        *tp,
1081         struct xfs_inode        *dp,
1082         struct xfs_buf          *bp,
1083         int                     first,
1084         int                     last)
1085 {
1086         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1087         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1088         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1089         struct xfs_dir2_leaf_entry *ents;
1090
1091         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1092                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1093                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1094                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1095
1096         ents = dp->d_ops->leaf_ents_p(leaf);
1097         firstlep = &ents[first];
1098         lastlep = &ents[last];
1099         xfs_trans_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1100                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1101 }
1102
1103 /*
1104  * Log the header of the leaf1 or leafn block.
1105  */
1106 void
1107 xfs_dir3_leaf_log_header(
1108         struct xfs_trans        *tp,
1109         struct xfs_inode        *dp,
1110         struct xfs_buf          *bp)
1111 {
1112         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1113
1114         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1115                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1116                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1117                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1118
1119         xfs_trans_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1120                           dp->d_ops->leaf_hdr_size - 1);
1121 }
1122
1123 /*
1124  * Log the tail of the leaf1 block.
1125  */
1126 STATIC void
1127 xfs_dir3_leaf_log_tail(
1128         struct xfs_trans        *tp,
1129         struct xfs_buf          *bp)
1130 {
1131         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1132         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1133         struct xfs_mount        *mp = tp->t_mountp;
1134
1135         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1136                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1137                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1138                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1139
1140         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1141         xfs_trans_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1142                 (uint)(mp->m_dirblksize - 1));
1143 }
1144
1145 /*
1146  * Look up the entry referred to by args in the leaf format directory.
1147  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1148  * is also used by the node-format code.
1149  */
1150 int
1151 xfs_dir2_leaf_lookup(
1152         xfs_da_args_t           *args)          /* operation arguments */
1153 {
1154         struct xfs_buf          *dbp;           /* data block buffer */
1155         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1156         xfs_inode_t             *dp;            /* incore directory inode */
1157         int                     error;          /* error return code */
1158         int                     index;          /* found entry index */
1159         struct xfs_buf          *lbp;           /* leaf buffer */
1160         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1161         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1162         xfs_trans_t             *tp;            /* transaction pointer */
1163         struct xfs_dir2_leaf_entry *ents;
1164
1165         trace_xfs_dir2_leaf_lookup(args);
1166
1167         /*
1168          * Look up name in the leaf block, returning both buffers and index.
1169          */
1170         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1171                 return error;
1172         }
1173         tp = args->trans;
1174         dp = args->dp;
1175         xfs_dir3_leaf_check(dp, lbp);
1176         leaf = lbp->b_addr;
1177         ents = dp->d_ops->leaf_ents_p(leaf);
1178         /*
1179          * Get to the leaf entry and contained data entry address.
1180          */
1181         lep = &ents[index];
1182
1183         /*
1184          * Point to the data entry.
1185          */
1186         dep = (xfs_dir2_data_entry_t *)
1187               ((char *)dbp->b_addr +
1188                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1189         /*
1190          * Return the found inode number & CI name if appropriate
1191          */
1192         args->inumber = be64_to_cpu(dep->inumber);
1193         args->filetype = dp->d_ops->data_get_ftype(dep);
1194         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1195         xfs_trans_brelse(tp, dbp);
1196         xfs_trans_brelse(tp, lbp);
1197         return XFS_ERROR(error);
1198 }
1199
1200 /*
1201  * Look up name/hash in the leaf block.
1202  * Fill in indexp with the found index, and dbpp with the data buffer.
1203  * If not found dbpp will be NULL, and ENOENT comes back.
1204  * lbpp will always be filled in with the leaf buffer unless there's an error.
1205  */
1206 static int                                      /* error */
1207 xfs_dir2_leaf_lookup_int(
1208         xfs_da_args_t           *args,          /* operation arguments */
1209         struct xfs_buf          **lbpp,         /* out: leaf buffer */
1210         int                     *indexp,        /* out: index in leaf block */
1211         struct xfs_buf          **dbpp)         /* out: data buffer */
1212 {
1213         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1214         struct xfs_buf          *dbp = NULL;    /* data buffer */
1215         xfs_dir2_data_entry_t   *dep;           /* data entry */
1216         xfs_inode_t             *dp;            /* incore directory inode */
1217         int                     error;          /* error return code */
1218         int                     index;          /* index in leaf block */
1219         struct xfs_buf          *lbp;           /* leaf buffer */
1220         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1221         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1222         xfs_mount_t             *mp;            /* filesystem mount point */
1223         xfs_dir2_db_t           newdb;          /* new data block number */
1224         xfs_trans_t             *tp;            /* transaction pointer */
1225         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1226         enum xfs_dacmp          cmp;            /* name compare result */
1227         struct xfs_dir2_leaf_entry *ents;
1228         struct xfs_dir3_icleaf_hdr leafhdr;
1229
1230         dp = args->dp;
1231         tp = args->trans;
1232         mp = dp->i_mount;
1233
1234         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
1235         if (error)
1236                 return error;
1237
1238         *lbpp = lbp;
1239         leaf = lbp->b_addr;
1240         xfs_dir3_leaf_check(dp, lbp);
1241         ents = dp->d_ops->leaf_ents_p(leaf);
1242         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1243
1244         /*
1245          * Look for the first leaf entry with our hash value.
1246          */
1247         index = xfs_dir2_leaf_search_hash(args, lbp);
1248         /*
1249          * Loop over all the entries with the right hash value
1250          * looking to match the name.
1251          */
1252         for (lep = &ents[index];
1253              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
1254              lep++, index++) {
1255                 /*
1256                  * Skip over stale leaf entries.
1257                  */
1258                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1259                         continue;
1260                 /*
1261                  * Get the new data block number.
1262                  */
1263                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1264                 /*
1265                  * If it's not the same as the old data block number,
1266                  * need to pitch the old one and read the new one.
1267                  */
1268                 if (newdb != curdb) {
1269                         if (dbp)
1270                                 xfs_trans_brelse(tp, dbp);
1271                         error = xfs_dir3_data_read(tp, dp,
1272                                                    xfs_dir2_db_to_da(mp, newdb),
1273                                                    -1, &dbp);
1274                         if (error) {
1275                                 xfs_trans_brelse(tp, lbp);
1276                                 return error;
1277                         }
1278                         curdb = newdb;
1279                 }
1280                 /*
1281                  * Point to the data entry.
1282                  */
1283                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1284                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1285                 /*
1286                  * Compare name and if it's an exact match, return the index
1287                  * and buffer. If it's the first case-insensitive match, store
1288                  * the index and buffer and continue looking for an exact match.
1289                  */
1290                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1291                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1292                         args->cmpresult = cmp;
1293                         *indexp = index;
1294                         /* case exact match: return the current buffer. */
1295                         if (cmp == XFS_CMP_EXACT) {
1296                                 *dbpp = dbp;
1297                                 return 0;
1298                         }
1299                         cidb = curdb;
1300                 }
1301         }
1302         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1303         /*
1304          * Here, we can only be doing a lookup (not a rename or remove).
1305          * If a case-insensitive match was found earlier, re-read the
1306          * appropriate data block if required and return it.
1307          */
1308         if (args->cmpresult == XFS_CMP_CASE) {
1309                 ASSERT(cidb != -1);
1310                 if (cidb != curdb) {
1311                         xfs_trans_brelse(tp, dbp);
1312                         error = xfs_dir3_data_read(tp, dp,
1313                                                    xfs_dir2_db_to_da(mp, cidb),
1314                                                    -1, &dbp);
1315                         if (error) {
1316                                 xfs_trans_brelse(tp, lbp);
1317                                 return error;
1318                         }
1319                 }
1320                 *dbpp = dbp;
1321                 return 0;
1322         }
1323         /*
1324          * No match found, return ENOENT.
1325          */
1326         ASSERT(cidb == -1);
1327         if (dbp)
1328                 xfs_trans_brelse(tp, dbp);
1329         xfs_trans_brelse(tp, lbp);
1330         return XFS_ERROR(ENOENT);
1331 }
1332
1333 /*
1334  * Remove an entry from a leaf format directory.
1335  */
1336 int                                             /* error */
1337 xfs_dir2_leaf_removename(
1338         xfs_da_args_t           *args)          /* operation arguments */
1339 {
1340         __be16                  *bestsp;        /* leaf block best freespace */
1341         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1342         xfs_dir2_db_t           db;             /* data block number */
1343         struct xfs_buf          *dbp;           /* data block buffer */
1344         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1345         xfs_inode_t             *dp;            /* incore directory inode */
1346         int                     error;          /* error return code */
1347         xfs_dir2_db_t           i;              /* temporary data block # */
1348         int                     index;          /* index into leaf entries */
1349         struct xfs_buf          *lbp;           /* leaf buffer */
1350         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1351         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1352         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1353         xfs_mount_t             *mp;            /* filesystem mount point */
1354         int                     needlog;        /* need to log data header */
1355         int                     needscan;       /* need to rescan data frees */
1356         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1357         xfs_trans_t             *tp;            /* transaction pointer */
1358         struct xfs_dir2_data_free *bf;          /* bestfree table */
1359         struct xfs_dir2_leaf_entry *ents;
1360         struct xfs_dir3_icleaf_hdr leafhdr;
1361
1362         trace_xfs_dir2_leaf_removename(args);
1363
1364         /*
1365          * Lookup the leaf entry, get the leaf and data blocks read in.
1366          */
1367         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1368                 return error;
1369         }
1370         dp = args->dp;
1371         tp = args->trans;
1372         mp = dp->i_mount;
1373         leaf = lbp->b_addr;
1374         hdr = dbp->b_addr;
1375         xfs_dir3_data_check(dp, dbp);
1376         bf = dp->d_ops->data_bestfree_p(hdr);
1377         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1378         ents = dp->d_ops->leaf_ents_p(leaf);
1379         /*
1380          * Point to the leaf entry, use that to point to the data entry.
1381          */
1382         lep = &ents[index];
1383         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1384         dep = (xfs_dir2_data_entry_t *)
1385               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1386         needscan = needlog = 0;
1387         oldbest = be16_to_cpu(bf[0].length);
1388         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1389         bestsp = xfs_dir2_leaf_bests_p(ltp);
1390         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1391         /*
1392          * Mark the former data entry unused.
1393          */
1394         xfs_dir2_data_make_free(tp, dp, dbp,
1395                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1396                 dp->d_ops->data_entsize(dep->namelen), &needlog, &needscan);
1397         /*
1398          * We just mark the leaf entry stale by putting a null in it.
1399          */
1400         leafhdr.stale++;
1401         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
1402         xfs_dir3_leaf_log_header(tp, dp, lbp);
1403
1404         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1405         xfs_dir3_leaf_log_ents(tp, dp, lbp, index, index);
1406
1407         /*
1408          * Scan the freespace in the data block again if necessary,
1409          * log the data block header if necessary.
1410          */
1411         if (needscan)
1412                 xfs_dir2_data_freescan(dp, hdr, &needlog);
1413         if (needlog)
1414                 xfs_dir2_data_log_header(tp, dp, dbp);
1415         /*
1416          * If the longest freespace in the data block has changed,
1417          * put the new value in the bests table and log that.
1418          */
1419         if (be16_to_cpu(bf[0].length) != oldbest) {
1420                 bestsp[db] = bf[0].length;
1421                 xfs_dir3_leaf_log_bests(tp, lbp, db, db);
1422         }
1423         xfs_dir3_data_check(dp, dbp);
1424         /*
1425          * If the data block is now empty then get rid of the data block.
1426          */
1427         if (be16_to_cpu(bf[0].length) ==
1428                         mp->m_dirblksize - dp->d_ops->data_entry_offset) {
1429                 ASSERT(db != mp->m_dirdatablk);
1430                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1431                         /*
1432                          * Nope, can't get rid of it because it caused
1433                          * allocation of a bmap btree block to do so.
1434                          * Just go on, returning success, leaving the
1435                          * empty block in place.
1436                          */
1437                         if (error == ENOSPC && args->total == 0)
1438                                 error = 0;
1439                         xfs_dir3_leaf_check(dp, lbp);
1440                         return error;
1441                 }
1442                 dbp = NULL;
1443                 /*
1444                  * If this is the last data block then compact the
1445                  * bests table by getting rid of entries.
1446                  */
1447                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1448                         /*
1449                          * Look for the last active entry (i).
1450                          */
1451                         for (i = db - 1; i > 0; i--) {
1452                                 if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1453                                         break;
1454                         }
1455                         /*
1456                          * Copy the table down so inactive entries at the
1457                          * end are removed.
1458                          */
1459                         memmove(&bestsp[db - i], bestsp,
1460                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1461                         be32_add_cpu(&ltp->bestcount, -(db - i));
1462                         xfs_dir3_leaf_log_tail(tp, lbp);
1463                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1464                 } else
1465                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1466         }
1467         /*
1468          * If the data block was not the first one, drop it.
1469          */
1470         else if (db != mp->m_dirdatablk)
1471                 dbp = NULL;
1472
1473         xfs_dir3_leaf_check(dp, lbp);
1474         /*
1475          * See if we can convert to block form.
1476          */
1477         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1478 }
1479
1480 /*
1481  * Replace the inode number in a leaf format directory entry.
1482  */
1483 int                                             /* error */
1484 xfs_dir2_leaf_replace(
1485         xfs_da_args_t           *args)          /* operation arguments */
1486 {
1487         struct xfs_buf          *dbp;           /* data block buffer */
1488         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1489         xfs_inode_t             *dp;            /* incore directory inode */
1490         int                     error;          /* error return code */
1491         int                     index;          /* index of leaf entry */
1492         struct xfs_buf          *lbp;           /* leaf buffer */
1493         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1494         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1495         xfs_trans_t             *tp;            /* transaction pointer */
1496         struct xfs_dir2_leaf_entry *ents;
1497
1498         trace_xfs_dir2_leaf_replace(args);
1499
1500         /*
1501          * Look up the entry.
1502          */
1503         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1504                 return error;
1505         }
1506         dp = args->dp;
1507         leaf = lbp->b_addr;
1508         ents = dp->d_ops->leaf_ents_p(leaf);
1509         /*
1510          * Point to the leaf entry, get data address from it.
1511          */
1512         lep = &ents[index];
1513         /*
1514          * Point to the data entry.
1515          */
1516         dep = (xfs_dir2_data_entry_t *)
1517               ((char *)dbp->b_addr +
1518                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1519         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1520         /*
1521          * Put the new inode number in, log it.
1522          */
1523         dep->inumber = cpu_to_be64(args->inumber);
1524         dp->d_ops->data_put_ftype(dep, args->filetype);
1525         tp = args->trans;
1526         xfs_dir2_data_log_entry(tp, dp, dbp, dep);
1527         xfs_dir3_leaf_check(dp, lbp);
1528         xfs_trans_brelse(tp, lbp);
1529         return 0;
1530 }
1531
1532 /*
1533  * Return index in the leaf block (lbp) which is either the first
1534  * one with this hash value, or if there are none, the insert point
1535  * for that hash value.
1536  */
1537 int                                             /* index value */
1538 xfs_dir2_leaf_search_hash(
1539         xfs_da_args_t           *args,          /* operation arguments */
1540         struct xfs_buf          *lbp)           /* leaf buffer */
1541 {
1542         xfs_dahash_t            hash=0;         /* hash from this entry */
1543         xfs_dahash_t            hashwant;       /* hash value looking for */
1544         int                     high;           /* high leaf index */
1545         int                     low;            /* low leaf index */
1546         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1547         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1548         int                     mid=0;          /* current leaf index */
1549         struct xfs_dir2_leaf_entry *ents;
1550         struct xfs_dir3_icleaf_hdr leafhdr;
1551
1552         leaf = lbp->b_addr;
1553         ents = args->dp->d_ops->leaf_ents_p(leaf);
1554         args->dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1555
1556         /*
1557          * Note, the table cannot be empty, so we have to go through the loop.
1558          * Binary search the leaf entries looking for our hash value.
1559          */
1560         for (lep = ents, low = 0, high = leafhdr.count - 1,
1561                 hashwant = args->hashval;
1562              low <= high; ) {
1563                 mid = (low + high) >> 1;
1564                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1565                         break;
1566                 if (hash < hashwant)
1567                         low = mid + 1;
1568                 else
1569                         high = mid - 1;
1570         }
1571         /*
1572          * Found one, back up through all the equal hash values.
1573          */
1574         if (hash == hashwant) {
1575                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1576                         mid--;
1577                 }
1578         }
1579         /*
1580          * Need to point to an entry higher than ours.
1581          */
1582         else if (hash < hashwant)
1583                 mid++;
1584         return mid;
1585 }
1586
1587 /*
1588  * Trim off a trailing data block.  We know it's empty since the leaf
1589  * freespace table says so.
1590  */
1591 int                                             /* error */
1592 xfs_dir2_leaf_trim_data(
1593         xfs_da_args_t           *args,          /* operation arguments */
1594         struct xfs_buf          *lbp,           /* leaf buffer */
1595         xfs_dir2_db_t           db)             /* data block number */
1596 {
1597         __be16                  *bestsp;        /* leaf bests table */
1598         struct xfs_buf          *dbp;           /* data block buffer */
1599         xfs_inode_t             *dp;            /* incore directory inode */
1600         int                     error;          /* error return value */
1601         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1602         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1603         xfs_mount_t             *mp;            /* filesystem mount point */
1604         xfs_trans_t             *tp;            /* transaction pointer */
1605
1606         dp = args->dp;
1607         mp = dp->i_mount;
1608         tp = args->trans;
1609         /*
1610          * Read the offending data block.  We need its buffer.
1611          */
1612         error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp);
1613         if (error)
1614                 return error;
1615
1616         leaf = lbp->b_addr;
1617         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1618
1619 #ifdef DEBUG
1620 {
1621         struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
1622         struct xfs_dir2_data_free *bf = dp->d_ops->data_bestfree_p(hdr);
1623
1624         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1625                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1626         ASSERT(be16_to_cpu(bf[0].length) ==
1627                mp->m_dirblksize - dp->d_ops->data_entry_offset);
1628         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1629 }
1630 #endif
1631
1632         /*
1633          * Get rid of the data block.
1634          */
1635         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1636                 ASSERT(error != ENOSPC);
1637                 xfs_trans_brelse(tp, dbp);
1638                 return error;
1639         }
1640         /*
1641          * Eliminate the last bests entry from the table.
1642          */
1643         bestsp = xfs_dir2_leaf_bests_p(ltp);
1644         be32_add_cpu(&ltp->bestcount, -1);
1645         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1646         xfs_dir3_leaf_log_tail(tp, lbp);
1647         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1648         return 0;
1649 }
1650
1651 static inline size_t
1652 xfs_dir3_leaf_size(
1653         struct xfs_dir3_icleaf_hdr      *hdr,
1654         int                             counts)
1655 {
1656         int     entries;
1657         int     hdrsize;
1658
1659         entries = hdr->count - hdr->stale;
1660         if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
1661             hdr->magic == XFS_DIR2_LEAFN_MAGIC)
1662                 hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
1663         else
1664                 hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
1665
1666         return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
1667                        + counts * sizeof(xfs_dir2_data_off_t)
1668                        + sizeof(xfs_dir2_leaf_tail_t);
1669 }
1670
1671 /*
1672  * Convert node form directory to leaf form directory.
1673  * The root of the node form dir needs to already be a LEAFN block.
1674  * Just return if we can't do anything.
1675  */
1676 int                                             /* error */
1677 xfs_dir2_node_to_leaf(
1678         xfs_da_state_t          *state)         /* directory operation state */
1679 {
1680         xfs_da_args_t           *args;          /* operation arguments */
1681         xfs_inode_t             *dp;            /* incore directory inode */
1682         int                     error;          /* error return code */
1683         struct xfs_buf          *fbp;           /* buffer for freespace block */
1684         xfs_fileoff_t           fo;             /* freespace file offset */
1685         xfs_dir2_free_t         *free;          /* freespace structure */
1686         struct xfs_buf          *lbp;           /* buffer for leaf block */
1687         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1688         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1689         xfs_mount_t             *mp;            /* filesystem mount point */
1690         int                     rval;           /* successful free trim? */
1691         xfs_trans_t             *tp;            /* transaction pointer */
1692         struct xfs_dir3_icleaf_hdr leafhdr;
1693         struct xfs_dir3_icfree_hdr freehdr;
1694
1695         /*
1696          * There's more than a leaf level in the btree, so there must
1697          * be multiple leafn blocks.  Give up.
1698          */
1699         if (state->path.active > 1)
1700                 return 0;
1701         args = state->args;
1702
1703         trace_xfs_dir2_node_to_leaf(args);
1704
1705         mp = state->mp;
1706         dp = args->dp;
1707         tp = args->trans;
1708         /*
1709          * Get the last offset in the file.
1710          */
1711         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1712                 return error;
1713         }
1714         fo -= mp->m_dirblkfsbs;
1715         /*
1716          * If there are freespace blocks other than the first one,
1717          * take this opportunity to remove trailing empty freespace blocks
1718          * that may have been left behind during no-space-reservation
1719          * operations.
1720          */
1721         while (fo > mp->m_dirfreeblk) {
1722                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1723                         return error;
1724                 }
1725                 if (rval)
1726                         fo -= mp->m_dirblkfsbs;
1727                 else
1728                         return 0;
1729         }
1730         /*
1731          * Now find the block just before the freespace block.
1732          */
1733         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1734                 return error;
1735         }
1736         /*
1737          * If it's not the single leaf block, give up.
1738          */
1739         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1740                 return 0;
1741         lbp = state->path.blk[0].bp;
1742         leaf = lbp->b_addr;
1743         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1744
1745         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
1746                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
1747
1748         /*
1749          * Read the freespace block.
1750          */
1751         error = xfs_dir2_free_read(tp, dp,  mp->m_dirfreeblk, &fbp);
1752         if (error)
1753                 return error;
1754         free = fbp->b_addr;
1755         dp->d_ops->free_hdr_from_disk(&freehdr, free);
1756
1757         ASSERT(!freehdr.firstdb);
1758
1759         /*
1760          * Now see if the leafn and free data will fit in a leaf1.
1761          * If not, release the buffer and give up.
1762          */
1763         if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > mp->m_dirblksize) {
1764                 xfs_trans_brelse(tp, fbp);
1765                 return 0;
1766         }
1767
1768         /*
1769          * If the leaf has any stale entries in it, compress them out.
1770          */
1771         if (leafhdr.stale)
1772                 xfs_dir3_leaf_compact(args, &leafhdr, lbp);
1773
1774         lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
1775         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
1776         leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
1777                                         ? XFS_DIR2_LEAF1_MAGIC
1778                                         : XFS_DIR3_LEAF1_MAGIC;
1779
1780         /*
1781          * Set up the leaf tail from the freespace block.
1782          */
1783         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1784         ltp->bestcount = cpu_to_be32(freehdr.nvalid);
1785
1786         /*
1787          * Set up the leaf bests table.
1788          */
1789         memcpy(xfs_dir2_leaf_bests_p(ltp), dp->d_ops->free_bests_p(free),
1790                 freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
1791
1792         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
1793         xfs_dir3_leaf_log_header(tp, dp, lbp);
1794         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1795         xfs_dir3_leaf_log_tail(tp, lbp);
1796         xfs_dir3_leaf_check(dp, lbp);
1797
1798         /*
1799          * Get rid of the freespace block.
1800          */
1801         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1802         if (error) {
1803                 /*
1804                  * This can't fail here because it can only happen when
1805                  * punching out the middle of an extent, and this is an
1806                  * isolated block.
1807                  */
1808                 ASSERT(error != ENOSPC);
1809                 return error;
1810         }
1811         fbp = NULL;
1812         /*
1813          * Now see if we can convert the single-leaf directory
1814          * down to a block form directory.
1815          * This routine always kills the dabuf for the leaf, so
1816          * eliminate it from the path.
1817          */
1818         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1819         state->path.blk[0].bp = NULL;
1820         return error;
1821 }