kernel/fs/xfs/libxfs/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_mount.h"
  25 #include "xfs_da_format.h"
  26 #include "xfs_da_btree.h"
  27 #include "xfs_inode.h"
  28 #include "xfs_bmap.h"
  29 #include "xfs_dir2.h"
  30 #include "xfs_dir2_priv.h"
  31 #include "xfs_error.h"
  32 #include "xfs_trace.h"
  33 #include "xfs_trans.h"
  34 #include "xfs_buf_item.h"
  35 #include "xfs_cksum.h"
  36 #include "xfs_log.h"
  37
  38 /*
  39  * Local function declarations.
  40  */
  41 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
  42                                     int *indexp, struct xfs_buf **dbpp);
  43 static void xfs_dir3_leaf_log_bests(struct xfs_da_args *args,
  44                                     struct xfs_buf *bp, int first, int last);
  45 static void xfs_dir3_leaf_log_tail(struct xfs_da_args *args,
  46                                    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         struct xfs_da_geometry  *geo = mp->m_dir_geo;
  96
  97         /*
  98          * we can be passed a null dp here from a verifier, so we need to go the
  99          * hard way to get them.
 100          */
 101         ops = xfs_dir_get_ops(mp, dp);
 102
 103         if (!hdr) {
 104                 ops->leaf_hdr_from_disk(&leafhdr, leaf);
 105                 hdr = &leafhdr;
 106         }
 107
 108         ents = ops->leaf_ents_p(leaf);
 109         ltp = xfs_dir2_leaf_tail_p(geo, leaf);
 110
 111         /*
 112          * XXX (dgc): This value is not restrictive enough.
 113          * Should factor in the size of the bests table as well.
 114          * We can deduce a value for that from di_size.
 115          */
 116         if (hdr->count > ops->leaf_max_ents(geo))
 117                 return false;
 118
 119         /* Leaves and bests don't overlap in leaf format. */
 120         if ((hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
 121              hdr->magic == XFS_DIR3_LEAF1_MAGIC) &&
 122             (char *)&ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
 123                 return false;
 124
 125         /* Check hash value order, count stale entries.  */
 126         for (i = stale = 0; i < hdr->count; i++) {
 127                 if (i + 1 < hdr->count) {
 128                         if (be32_to_cpu(ents[i].hashval) >
 129                                         be32_to_cpu(ents[i + 1].hashval))
 130                                 return false;
 131                 }
 132                 if (ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 133                         stale++;
 134         }
 135         if (hdr->stale != stale)
 136                 return false;
 137         return true;
 138 }
 139
 140 /*
 141  * We verify the magic numbers before decoding the leaf header so that on debug
 142  * kernels we don't get assertion failures in xfs_dir3_leaf_hdr_from_disk() due
 143  * to incorrect magic numbers.
 144  */
 145 static bool
 146 xfs_dir3_leaf_verify(
 147         struct xfs_buf          *bp,
 148         __uint16_t              magic)
 149 {
 150         struct xfs_mount        *mp = bp->b_target->bt_mount;
 151         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 152
 153         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 154
 155         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 156                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 157                 __uint16_t              magic3;
 158
 159                 magic3 = (magic == XFS_DIR2_LEAF1_MAGIC) ? XFS_DIR3_LEAF1_MAGIC
 160                                                          : XFS_DIR3_LEAFN_MAGIC;
 161
 162                 if (leaf3->info.hdr.magic != cpu_to_be16(magic3))
 163                         return false;
 164                 if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_meta_uuid))
 165                         return false;
 166                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
 167                         return false;
 168                 if (!xfs_log_check_lsn(mp, be64_to_cpu(leaf3->info.lsn)))
 169                         return false;
 170         } else {
 171                 if (leaf->hdr.info.magic != cpu_to_be16(magic))
 172                         return false;
 173         }
 174
 175         return xfs_dir3_leaf_check_int(mp, NULL, NULL, leaf);
 176 }
 177
 178 static void
 179 __read_verify(
 180         struct xfs_buf  *bp,
 181         __uint16_t      magic)
 182 {
 183         struct xfs_mount        *mp = bp->b_target->bt_mount;
 184
 185         if (xfs_sb_version_hascrc(&mp->m_sb) &&
 186              !xfs_buf_verify_cksum(bp, XFS_DIR3_LEAF_CRC_OFF))
 187                 xfs_buf_ioerror(bp, -EFSBADCRC);
 188         else if (!xfs_dir3_leaf_verify(bp, magic))
 189                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 190
 191         if (bp->b_error)
 192                 xfs_verifier_error(bp);
 193 }
 194
 195 static void
 196 __write_verify(
 197         struct xfs_buf  *bp,
 198         __uint16_t      magic)
 199 {
 200         struct xfs_mount        *mp = bp->b_target->bt_mount;
 201         struct xfs_buf_log_item *bip = bp->b_fspriv;
 202         struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 203
 204         if (!xfs_dir3_leaf_verify(bp, magic)) {
 205                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 206                 xfs_verifier_error(bp);
 207                 return;
 208         }
 209
 210         if (!xfs_sb_version_hascrc(&mp->m_sb))
 211                 return;
 212
 213         if (bip)
 214                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 215
 216         xfs_buf_update_cksum(bp, XFS_DIR3_LEAF_CRC_OFF);
 217 }
 218
 219 static void
 220 xfs_dir3_leaf1_read_verify(
 221         struct xfs_buf  *bp)
 222 {
 223         __read_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 224 }
 225
 226 static void
 227 xfs_dir3_leaf1_write_verify(
 228         struct xfs_buf  *bp)
 229 {
 230         __write_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 231 }
 232
 233 static void
 234 xfs_dir3_leafn_read_verify(
 235         struct xfs_buf  *bp)
 236 {
 237         __read_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 238 }
 239
 240 static void
 241 xfs_dir3_leafn_write_verify(
 242         struct xfs_buf  *bp)
 243 {
 244         __write_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 245 }
 246
 247 const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 248         .verify_read = xfs_dir3_leaf1_read_verify,
 249         .verify_write = xfs_dir3_leaf1_write_verify,
 250 };
 251
 252 const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 253         .verify_read = xfs_dir3_leafn_read_verify,
 254         .verify_write = xfs_dir3_leafn_write_verify,
 255 };
 256
 257 static int
 258 xfs_dir3_leaf_read(
 259         struct xfs_trans        *tp,
 260         struct xfs_inode        *dp,
 261         xfs_dablk_t             fbno,
 262         xfs_daddr_t             mappedbno,
 263         struct xfs_buf          **bpp)
 264 {
 265         int                     err;
 266
 267         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 268                                 XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
 269         if (!err && tp)
 270                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 271         return err;
 272 }
 273
 274 int
 275 xfs_dir3_leafn_read(
 276         struct xfs_trans        *tp,
 277         struct xfs_inode        *dp,
 278         xfs_dablk_t             fbno,
 279         xfs_daddr_t             mappedbno,
 280         struct xfs_buf          **bpp)
 281 {
 282         int                     err;
 283
 284         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 285                                 XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
 286         if (!err && tp)
 287                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 288         return err;
 289 }
 290
 291 /*
 292  * Initialize a new leaf block, leaf1 or leafn magic accepted.
 293  */
 294 static void
 295 xfs_dir3_leaf_init(
 296         struct xfs_mount        *mp,
 297         struct xfs_trans        *tp,
 298         struct xfs_buf          *bp,
 299         xfs_ino_t               owner,
 300         __uint16_t              type)
 301 {
 302         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 303
 304         ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 305
 306         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 307                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 308
 309                 memset(leaf3, 0, sizeof(*leaf3));
 310
 311                 leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 312                                          ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 313                                          : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 314                 leaf3->info.blkno = cpu_to_be64(bp->b_bn);
 315                 leaf3->info.owner = cpu_to_be64(owner);
 316                 uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_meta_uuid);
 317         } else {
 318                 memset(leaf, 0, sizeof(*leaf));
 319                 leaf->hdr.info.magic = cpu_to_be16(type);
 320         }
 321
 322         /*
 323          * If it's a leaf-format directory initialize the tail.
 324          * Caller is responsible for initialising the bests table.
 325          */
 326         if (type == XFS_DIR2_LEAF1_MAGIC) {
 327                 struct xfs_dir2_leaf_tail *ltp;
 328
 329                 ltp = xfs_dir2_leaf_tail_p(mp->m_dir_geo, leaf);
 330                 ltp->bestcount = 0;
 331                 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 332                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 333         } else {
 334                 bp->b_ops = &xfs_dir3_leafn_buf_ops;
 335                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 336         }
 337 }
 338
 339 int
 340 xfs_dir3_leaf_get_buf(
 341         xfs_da_args_t           *args,
 342         xfs_dir2_db_t           bno,
 343         struct xfs_buf          **bpp,
 344         __uint16_t              magic)
 345 {
 346         struct xfs_inode        *dp = args->dp;
 347         struct xfs_trans        *tp = args->trans;
 348         struct xfs_mount        *mp = dp->i_mount;
 349         struct xfs_buf          *bp;
 350         int                     error;
 351
 352         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 353         ASSERT(bno >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET) &&
 354                bno < xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET));
 355
 356         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, bno),
 357                                -1, &bp, XFS_DATA_FORK);
 358         if (error)
 359                 return error;
 360
 361         xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
 362         xfs_dir3_leaf_log_header(args, bp);
 363         if (magic == XFS_DIR2_LEAF1_MAGIC)
 364                 xfs_dir3_leaf_log_tail(args, bp);
 365         *bpp = bp;
 366         return 0;
 367 }
 368
 369 /*
 370  * Convert a block form directory to a leaf form directory.
 371  */
 372 int                                             /* error */
 373 xfs_dir2_block_to_leaf(
 374         xfs_da_args_t           *args,          /* operation arguments */
 375         struct xfs_buf          *dbp)           /* input block's buffer */
 376 {
 377         __be16                  *bestsp;        /* leaf's bestsp entries */
 378         xfs_dablk_t             blkno;          /* leaf block's bno */
 379         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 380         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
 381         xfs_dir2_block_tail_t   *btp;           /* block's tail */
 382         xfs_inode_t             *dp;            /* incore directory inode */
 383         int                     error;          /* error return code */
 384         struct xfs_buf          *lbp;           /* leaf block's buffer */
 385         xfs_dir2_db_t           ldb;            /* leaf block's bno */
 386         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 387         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
 388         int                     needlog;        /* need to log block header */
 389         int                     needscan;       /* need to rescan bestfree */
 390         xfs_trans_t             *tp;            /* transaction pointer */
 391         struct xfs_dir2_data_free *bf;
 392         struct xfs_dir2_leaf_entry *ents;
 393         struct xfs_dir3_icleaf_hdr leafhdr;
 394
 395         trace_xfs_dir2_block_to_leaf(args);
 396
 397         dp = args->dp;
 398         tp = args->trans;
 399         /*
 400          * Add the leaf block to the inode.
 401          * This interface will only put blocks in the leaf/node range.
 402          * Since that's empty now, we'll get the root (block 0 in range).
 403          */
 404         if ((error = xfs_da_grow_inode(args, &blkno))) {
 405                 return error;
 406         }
 407         ldb = xfs_dir2_da_to_db(args->geo, blkno);
 408         ASSERT(ldb == xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET));
 409         /*
 410          * Initialize the leaf block, get a buffer for it.
 411          */
 412         error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 413         if (error)
 414                 return error;
 415
 416         leaf = lbp->b_addr;
 417         hdr = dbp->b_addr;
 418         xfs_dir3_data_check(dp, dbp);
 419         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 420         blp = xfs_dir2_block_leaf_p(btp);
 421         bf = dp->d_ops->data_bestfree_p(hdr);
 422         ents = dp->d_ops->leaf_ents_p(leaf);
 423
 424         /*
 425          * Set the counts in the leaf header.
 426          */
 427         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 428         leafhdr.count = be32_to_cpu(btp->count);
 429         leafhdr.stale = be32_to_cpu(btp->stale);
 430         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 431         xfs_dir3_leaf_log_header(args, lbp);
 432
 433         /*
 434          * Could compact these but I think we always do the conversion
 435          * after squeezing out stale entries.
 436          */
 437         memcpy(ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
 438         xfs_dir3_leaf_log_ents(args, lbp, 0, leafhdr.count - 1);
 439         needscan = 0;
 440         needlog = 1;
 441         /*
 442          * Make the space formerly occupied by the leaf entries and block
 443          * tail be free.
 444          */
 445         xfs_dir2_data_make_free(args, dbp,
 446                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 447                 (xfs_dir2_data_aoff_t)((char *)hdr + args->geo->blksize -
 448                                        (char *)blp),
 449                 &needlog, &needscan);
 450         /*
 451          * Fix up the block header, make it a data block.
 452          */
 453         dbp->b_ops = &xfs_dir3_data_buf_ops;
 454         xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 455         if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 456                 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 457         else
 458                 hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 459
 460         if (needscan)
 461                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 462         /*
 463          * Set up leaf tail and bests table.
 464          */
 465         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 466         ltp->bestcount = cpu_to_be32(1);
 467         bestsp = xfs_dir2_leaf_bests_p(ltp);
 468         bestsp[0] =  bf[0].length;
 469         /*
 470          * Log the data header and leaf bests table.
 471          */
 472         if (needlog)
 473                 xfs_dir2_data_log_header(args, dbp);
 474         xfs_dir3_leaf_check(dp, lbp);
 475         xfs_dir3_data_check(dp, dbp);
 476         xfs_dir3_leaf_log_bests(args, lbp, 0, 0);
 477         return 0;
 478 }
 479
 480 STATIC void
 481 xfs_dir3_leaf_find_stale(
 482         struct xfs_dir3_icleaf_hdr *leafhdr,
 483         struct xfs_dir2_leaf_entry *ents,
 484         int                     index,
 485         int                     *lowstale,
 486         int                     *highstale)
 487 {
 488         /*
 489          * Find the first stale entry before our index, if any.
 490          */
 491         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 492                 if (ents[*lowstale].address ==
 493                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 494                         break;
 495         }
 496
 497         /*
 498          * Find the first stale entry at or after our index, if any.
 499          * Stop if the result would require moving more entries than using
 500          * lowstale.
 501          */
 502         for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 503                 if (ents[*highstale].address ==
 504                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 505                         break;
 506                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 507                         break;
 508         }
 509 }
 510
 511 struct xfs_dir2_leaf_entry *
 512 xfs_dir3_leaf_find_entry(
 513         struct xfs_dir3_icleaf_hdr *leafhdr,
 514         struct xfs_dir2_leaf_entry *ents,
 515         int                     index,          /* leaf table position */
 516         int                     compact,        /* need to compact leaves */
 517         int                     lowstale,       /* index of prev stale leaf */
 518         int                     highstale,      /* index of next stale leaf */
 519         int                     *lfloglow,      /* low leaf logging index */
 520         int                     *lfloghigh)     /* high leaf logging index */
 521 {
 522         if (!leafhdr->stale) {
 523                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 524
 525                 /*
 526                  * Now we need to make room to insert the leaf entry.
 527                  *
 528                  * If there are no stale entries, just insert a hole at index.
 529                  */
 530                 lep = &ents[index];
 531                 if (index < leafhdr->count)
 532                         memmove(lep + 1, lep,
 533                                 (leafhdr->count - index) * sizeof(*lep));
 534
 535                 /*
 536                  * Record low and high logging indices for the leaf.
 537                  */
 538                 *lfloglow = index;
 539                 *lfloghigh = leafhdr->count++;
 540                 return lep;
 541         }
 542
 543         /*
 544          * There are stale entries.
 545          *
 546          * We will use one of them for the new entry.  It's probably not at
 547          * the right location, so we'll have to shift some up or down first.
 548          *
 549          * If we didn't compact before, we need to find the nearest stale
 550          * entries before and after our insertion point.
 551          */
 552         if (compact == 0)
 553                 xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 554                                          &lowstale, &highstale);
 555
 556         /*
 557          * If the low one is better, use it.
 558          */
 559         if (lowstale >= 0 &&
 560             (highstale == leafhdr->count ||
 561              index - lowstale - 1 < highstale - index)) {
 562                 ASSERT(index - lowstale - 1 >= 0);
 563                 ASSERT(ents[lowstale].address ==
 564                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 565
 566                 /*
 567                  * Copy entries up to cover the stale entry and make room
 568                  * for the new entry.
 569                  */
 570                 if (index - lowstale - 1 > 0) {
 571                         memmove(&ents[lowstale], &ents[lowstale + 1],
 572                                 (index - lowstale - 1) *
 573                                         sizeof(xfs_dir2_leaf_entry_t));
 574                 }
 575                 *lfloglow = MIN(lowstale, *lfloglow);
 576                 *lfloghigh = MAX(index - 1, *lfloghigh);
 577                 leafhdr->stale--;
 578                 return &ents[index - 1];
 579         }
 580
 581         /*
 582          * The high one is better, so use that one.
 583          */
 584         ASSERT(highstale - index >= 0);
 585         ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 586
 587         /*
 588          * Copy entries down to cover the stale entry and make room for the
 589          * new entry.
 590          */
 591         if (highstale - index > 0) {
 592                 memmove(&ents[index + 1], &ents[index],
 593                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 594         }
 595         *lfloglow = MIN(index, *lfloglow);
 596         *lfloghigh = MAX(highstale, *lfloghigh);
 597         leafhdr->stale--;
 598         return &ents[index];
 599 }
 600
 601 /*
 602  * Add an entry to a leaf form directory.
 603  */
 604 int                                             /* error */
 605 xfs_dir2_leaf_addname(
 606         xfs_da_args_t           *args)          /* operation arguments */
 607 {
 608         __be16                  *bestsp;        /* freespace table in leaf */
 609         int                     compact;        /* need to compact leaves */
 610         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 611         struct xfs_buf          *dbp;           /* data block buffer */
 612         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 613         xfs_inode_t             *dp;            /* incore directory inode */
 614         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 615         int                     error;          /* error return value */
 616         int                     grown;          /* allocated new data block */
 617         int                     highstale;      /* index of next stale leaf */
 618         int                     i;              /* temporary, index */
 619         int                     index;          /* leaf table position */
 620         struct xfs_buf          *lbp;           /* leaf's buffer */
 621         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 622         int                     length;         /* length of new entry */
 623         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 624         int                     lfloglow;       /* low leaf logging index */
 625         int                     lfloghigh;      /* high leaf logging index */
 626         int                     lowstale;       /* index of prev stale leaf */
 627         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 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
 643         error = xfs_dir3_leaf_read(tp, dp, args->geo->leafblk, -1, &lbp);
 644         if (error)
 645                 return error;
 646
 647         /*
 648          * Look up the entry by hash value and name.
 649          * We know it's not there, our caller has already done a lookup.
 650          * So the index is of the entry to insert in front of.
 651          * But if there are dup hash values the index is of the first of those.
 652          */
 653         index = xfs_dir2_leaf_search_hash(args, lbp);
 654         leaf = lbp->b_addr;
 655         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 656         ents = dp->d_ops->leaf_ents_p(leaf);
 657         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 658         bestsp = xfs_dir2_leaf_bests_p(ltp);
 659         length = dp->d_ops->data_entsize(args->namelen);
 660
 661         /*
 662          * See if there are any entries with the same hash value
 663          * and space in their block for the new entry.
 664          * This is good because it puts multiple same-hash value entries
 665          * in a data block, improving the lookup of those entries.
 666          */
 667         for (use_block = -1, lep = &ents[index];
 668              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 669              index++, lep++) {
 670                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 671                         continue;
 672                 i = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address));
 673                 ASSERT(i < be32_to_cpu(ltp->bestcount));
 674                 ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 675                 if (be16_to_cpu(bestsp[i]) >= length) {
 676                         use_block = i;
 677                         break;
 678                 }
 679         }
 680         /*
 681          * Didn't find a block yet, linear search all the data blocks.
 682          */
 683         if (use_block == -1) {
 684                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 685                         /*
 686                          * Remember a block we see that's missing.
 687                          */
 688                         if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 689                             use_block == -1)
 690                                 use_block = i;
 691                         else if (be16_to_cpu(bestsp[i]) >= length) {
 692                                 use_block = i;
 693                                 break;
 694                         }
 695                 }
 696         }
 697         /*
 698          * How many bytes do we need in the leaf block?
 699          */
 700         needbytes = 0;
 701         if (!leafhdr.stale)
 702                 needbytes += sizeof(xfs_dir2_leaf_entry_t);
 703         if (use_block == -1)
 704                 needbytes += sizeof(xfs_dir2_data_off_t);
 705
 706         /*
 707          * Now kill use_block if it refers to a missing block, so we
 708          * can use it as an indication of allocation needed.
 709          */
 710         if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 711                 use_block = -1;
 712         /*
 713          * If we don't have enough free bytes but we can make enough
 714          * by compacting out stale entries, we'll do that.
 715          */
 716         if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
 717             leafhdr.stale > 1)
 718                 compact = 1;
 719
 720         /*
 721          * Otherwise if we don't have enough free bytes we need to
 722          * convert to node form.
 723          */
 724         else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
 725                 /*
 726                  * Just checking or no space reservation, give up.
 727                  */
 728                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 729                                                         args->total == 0) {
 730                         xfs_trans_brelse(tp, lbp);
 731                         return -ENOSPC;
 732                 }
 733                 /*
 734                  * Convert to node form.
 735                  */
 736                 error = xfs_dir2_leaf_to_node(args, lbp);
 737                 if (error)
 738                         return error;
 739                 /*
 740                  * Then add the new entry.
 741                  */
 742                 return xfs_dir2_node_addname(args);
 743         }
 744         /*
 745          * Otherwise it will fit without compaction.
 746          */
 747         else
 748                 compact = 0;
 749         /*
 750          * If just checking, then it will fit unless we needed to allocate
 751          * a new data block.
 752          */
 753         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 754                 xfs_trans_brelse(tp, lbp);
 755                 return use_block == -1 ? -ENOSPC : 0;
 756         }
 757         /*
 758          * If no allocations are allowed, return now before we've
 759          * changed anything.
 760          */
 761         if (args->total == 0 && use_block == -1) {
 762                 xfs_trans_brelse(tp, lbp);
 763                 return -ENOSPC;
 764         }
 765         /*
 766          * Need to compact the leaf entries, removing stale ones.
 767          * Leave one stale entry behind - the one closest to our
 768          * insertion index - and we'll shift that one to our insertion
 769          * point later.
 770          */
 771         if (compact) {
 772                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 773                         &highstale, &lfloglow, &lfloghigh);
 774         }
 775         /*
 776          * There are stale entries, so we'll need log-low and log-high
 777          * impossibly bad values later.
 778          */
 779         else if (leafhdr.stale) {
 780                 lfloglow = leafhdr.count;
 781                 lfloghigh = -1;
 782         }
 783         /*
 784          * If there was no data block space found, we need to allocate
 785          * a new one.
 786          */
 787         if (use_block == -1) {
 788                 /*
 789                  * Add the new data block.
 790                  */
 791                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 792                                 &use_block))) {
 793                         xfs_trans_brelse(tp, lbp);
 794                         return error;
 795                 }
 796                 /*
 797                  * Initialize the block.
 798                  */
 799                 if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
 800                         xfs_trans_brelse(tp, lbp);
 801                         return error;
 802                 }
 803                 /*
 804                  * If we're adding a new data block on the end we need to
 805                  * extend the bests table.  Copy it up one entry.
 806                  */
 807                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
 808                         bestsp--;
 809                         memmove(&bestsp[0], &bestsp[1],
 810                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 811                         be32_add_cpu(&ltp->bestcount, 1);
 812                         xfs_dir3_leaf_log_tail(args, lbp);
 813                         xfs_dir3_leaf_log_bests(args, lbp, 0,
 814                                                 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(args, 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(args->geo, 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(args, 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(args, dbp);
 874         xfs_dir2_data_log_entry(args, 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(args, 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(
 893                                 xfs_dir2_db_off_to_dataptr(args->geo, use_block,
 894                                 be16_to_cpu(*tagp)));
 895         /*
 896          * Log the leaf fields and give up the buffers.
 897          */
 898         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 899         xfs_dir3_leaf_log_header(args, lbp);
 900         xfs_dir3_leaf_log_ents(args, lbp, lfloglow, lfloghigh);
 901         xfs_dir3_leaf_check(dp, lbp);
 902         xfs_dir3_data_check(dp, dbp);
 903         return 0;
 904 }
 905
 906 /*
 907  * Compact out any stale entries in the leaf.
 908  * Log the header and changed leaf entries, if any.
 909  */
 910 void
 911 xfs_dir3_leaf_compact(
 912         xfs_da_args_t   *args,          /* operation arguments */
 913         struct xfs_dir3_icleaf_hdr *leafhdr,
 914         struct xfs_buf  *bp)            /* leaf buffer */
 915 {
 916         int             from;           /* source leaf index */
 917         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 918         int             loglow;         /* first leaf entry to log */
 919         int             to;             /* target leaf index */
 920         struct xfs_dir2_leaf_entry *ents;
 921         struct xfs_inode *dp = args->dp;
 922
 923         leaf = bp->b_addr;
 924         if (!leafhdr->stale)
 925                 return;
 926
 927         /*
 928          * Compress out the stale entries in place.
 929          */
 930         ents = dp->d_ops->leaf_ents_p(leaf);
 931         for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 932                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 933                         continue;
 934                 /*
 935                  * Only actually copy the entries that are different.
 936                  */
 937                 if (from > to) {
 938                         if (loglow == -1)
 939                                 loglow = to;
 940                         ents[to] = ents[from];
 941                 }
 942                 to++;
 943         }
 944         /*
 945          * Update and log the header, log the leaf entries.
 946          */
 947         ASSERT(leafhdr->stale == from - to);
 948         leafhdr->count -= leafhdr->stale;
 949         leafhdr->stale = 0;
 950
 951         dp->d_ops->leaf_hdr_to_disk(leaf, leafhdr);
 952         xfs_dir3_leaf_log_header(args, bp);
 953         if (loglow != -1)
 954                 xfs_dir3_leaf_log_ents(args, bp, loglow, to - 1);
 955 }
 956
 957 /*
 958  * Compact the leaf entries, removing stale ones.
 959  * Leave one stale entry behind - the one closest to our
 960  * insertion index - and the caller will shift that one to our insertion
 961  * point later.
 962  * Return new insertion index, where the remaining stale entry is,
 963  * and leaf logging indices.
 964  */
 965 void
 966 xfs_dir3_leaf_compact_x1(
 967         struct xfs_dir3_icleaf_hdr *leafhdr,
 968         struct xfs_dir2_leaf_entry *ents,
 969         int             *indexp,        /* insertion index */
 970         int             *lowstalep,     /* out: stale entry before us */
 971         int             *highstalep,    /* out: stale entry after us */
 972         int             *lowlogp,       /* out: low log index */
 973         int             *highlogp)      /* out: high log index */
 974 {
 975         int             from;           /* source copy index */
 976         int             highstale;      /* stale entry at/after index */
 977         int             index;          /* insertion index */
 978         int             keepstale;      /* source index of kept stale */
 979         int             lowstale;       /* stale entry before index */
 980         int             newindex=0;     /* new insertion index */
 981         int             to;             /* destination copy index */
 982
 983         ASSERT(leafhdr->stale > 1);
 984         index = *indexp;
 985
 986         xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
 987
 988         /*
 989          * Pick the better of lowstale and highstale.
 990          */
 991         if (lowstale >= 0 &&
 992             (highstale == leafhdr->count ||
 993              index - lowstale <= highstale - index))
 994                 keepstale = lowstale;
 995         else
 996                 keepstale = highstale;
 997         /*
 998          * Copy the entries in place, removing all the stale entries
 999          * except keepstale.
1000          */
1001         for (from = to = 0; from < leafhdr->count; from++) {
1002                 /*
1003                  * Notice the new value of index.
1004                  */
1005                 if (index == from)
1006                         newindex = to;
1007                 if (from != keepstale &&
1008                     ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1009                         if (from == to)
1010                                 *lowlogp = to;
1011                         continue;
1012                 }
1013                 /*
1014                  * Record the new keepstale value for the insertion.
1015                  */
1016                 if (from == keepstale)
1017                         lowstale = highstale = to;
1018                 /*
1019                  * Copy only the entries that have moved.
1020                  */
1021                 if (from > to)
1022                         ents[to] = ents[from];
1023                 to++;
1024         }
1025         ASSERT(from > to);
1026         /*
1027          * If the insertion point was past the last entry,
1028          * set the new insertion point accordingly.
1029          */
1030         if (index == from)
1031                 newindex = to;
1032         *indexp = newindex;
1033         /*
1034          * Adjust the leaf header values.
1035          */
1036         leafhdr->count -= from - to;
1037         leafhdr->stale = 1;
1038         /*
1039          * Remember the low/high stale value only in the "right"
1040          * direction.
1041          */
1042         if (lowstale >= newindex)
1043                 lowstale = -1;
1044         else
1045                 highstale = leafhdr->count;
1046         *highlogp = leafhdr->count - 1;
1047         *lowstalep = lowstale;
1048         *highstalep = highstale;
1049 }
1050
1051 /*
1052  * Log the bests entries indicated from a leaf1 block.
1053  */
1054 static void
1055 xfs_dir3_leaf_log_bests(
1056         struct xfs_da_args      *args,
1057         struct xfs_buf          *bp,            /* leaf buffer */
1058         int                     first,          /* first entry to log */
1059         int                     last)           /* last entry to log */
1060 {
1061         __be16                  *firstb;        /* pointer to first entry */
1062         __be16                  *lastb;         /* pointer to last entry */
1063         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1064         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1065
1066         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1067                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1068
1069         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1070         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1071         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1072         xfs_trans_log_buf(args->trans, bp,
1073                 (uint)((char *)firstb - (char *)leaf),
1074                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1075 }
1076
1077 /*
1078  * Log the leaf entries indicated from a leaf1 or leafn block.
1079  */
1080 void
1081 xfs_dir3_leaf_log_ents(
1082         struct xfs_da_args      *args,
1083         struct xfs_buf          *bp,
1084         int                     first,
1085         int                     last)
1086 {
1087         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1088         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1089         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1090         struct xfs_dir2_leaf_entry *ents;
1091
1092         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1093                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1094                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1095                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1096
1097         ents = args->dp->d_ops->leaf_ents_p(leaf);
1098         firstlep = &ents[first];
1099         lastlep = &ents[last];
1100         xfs_trans_log_buf(args->trans, bp,
1101                 (uint)((char *)firstlep - (char *)leaf),
1102                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1103 }
1104
1105 /*
1106  * Log the header of the leaf1 or leafn block.
1107  */
1108 void
1109 xfs_dir3_leaf_log_header(
1110         struct xfs_da_args      *args,
1111         struct xfs_buf          *bp)
1112 {
1113         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1114
1115         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1116                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1117                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1118                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1119
1120         xfs_trans_log_buf(args->trans, bp,
1121                           (uint)((char *)&leaf->hdr - (char *)leaf),
1122                           args->dp->d_ops->leaf_hdr_size - 1);
1123 }
1124
1125 /*
1126  * Log the tail of the leaf1 block.
1127  */
1128 STATIC void
1129 xfs_dir3_leaf_log_tail(
1130         struct xfs_da_args      *args,
1131         struct xfs_buf          *bp)
1132 {
1133         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1134         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1135
1136         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1137                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1138                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1139                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1140
1141         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1142         xfs_trans_log_buf(args->trans, bp, (uint)((char *)ltp - (char *)leaf),
1143                 (uint)(args->geo->blksize - 1));
1144 }
1145
1146 /*
1147  * Look up the entry referred to by args in the leaf format directory.
1148  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1149  * is also used by the node-format code.
1150  */
1151 int
1152 xfs_dir2_leaf_lookup(
1153         xfs_da_args_t           *args)          /* operation arguments */
1154 {
1155         struct xfs_buf          *dbp;           /* data block buffer */
1156         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1157         xfs_inode_t             *dp;            /* incore directory inode */
1158         int                     error;          /* error return code */
1159         int                     index;          /* found entry index */
1160         struct xfs_buf          *lbp;           /* leaf buffer */
1161         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1162         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1163         xfs_trans_t             *tp;            /* transaction pointer */
1164         struct xfs_dir2_leaf_entry *ents;
1165
1166         trace_xfs_dir2_leaf_lookup(args);
1167
1168         /*
1169          * Look up name in the leaf block, returning both buffers and index.
1170          */
1171         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1172                 return error;
1173         }
1174         tp = args->trans;
1175         dp = args->dp;
1176         xfs_dir3_leaf_check(dp, lbp);
1177         leaf = lbp->b_addr;
1178         ents = dp->d_ops->leaf_ents_p(leaf);
1179         /*
1180          * Get to the leaf entry and contained data entry address.
1181          */
1182         lep = &ents[index];
1183
1184         /*
1185          * Point to the data entry.
1186          */
1187         dep = (xfs_dir2_data_entry_t *)
1188               ((char *)dbp->b_addr +
1189                xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1190         /*
1191          * Return the found inode number & CI name if appropriate
1192          */
1193         args->inumber = be64_to_cpu(dep->inumber);
1194         args->filetype = dp->d_ops->data_get_ftype(dep);
1195         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1196         xfs_trans_brelse(tp, dbp);
1197         xfs_trans_brelse(tp, lbp);
1198         return error;
1199 }
1200
1201 /*
1202  * Look up name/hash in the leaf block.
1203  * Fill in indexp with the found index, and dbpp with the data buffer.
1204  * If not found dbpp will be NULL, and ENOENT comes back.
1205  * lbpp will always be filled in with the leaf buffer unless there's an error.
1206  */
1207 static int                                      /* error */
1208 xfs_dir2_leaf_lookup_int(
1209         xfs_da_args_t           *args,          /* operation arguments */
1210         struct xfs_buf          **lbpp,         /* out: leaf buffer */
1211         int                     *indexp,        /* out: index in leaf block */
1212         struct xfs_buf          **dbpp)         /* out: data buffer */
1213 {
1214         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1215         struct xfs_buf          *dbp = NULL;    /* data buffer */
1216         xfs_dir2_data_entry_t   *dep;           /* data entry */
1217         xfs_inode_t             *dp;            /* incore directory inode */
1218         int                     error;          /* error return code */
1219         int                     index;          /* index in leaf block */
1220         struct xfs_buf          *lbp;           /* leaf buffer */
1221         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1222         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1223         xfs_mount_t             *mp;            /* filesystem mount point */
1224         xfs_dir2_db_t           newdb;          /* new data block number */
1225         xfs_trans_t             *tp;            /* transaction pointer */
1226         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1227         enum xfs_dacmp          cmp;            /* name compare result */
1228         struct xfs_dir2_leaf_entry *ents;
1229         struct xfs_dir3_icleaf_hdr leafhdr;
1230
1231         dp = args->dp;
1232         tp = args->trans;
1233         mp = dp->i_mount;
1234
1235         error = xfs_dir3_leaf_read(tp, dp, args->geo->leafblk, -1, &lbp);
1236         if (error)
1237                 return error;
1238
1239         *lbpp = lbp;
1240         leaf = lbp->b_addr;
1241         xfs_dir3_leaf_check(dp, lbp);
1242         ents = dp->d_ops->leaf_ents_p(leaf);
1243         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1244
1245         /*
1246          * Look for the first leaf entry with our hash value.
1247          */
1248         index = xfs_dir2_leaf_search_hash(args, lbp);
1249         /*
1250          * Loop over all the entries with the right hash value
1251          * looking to match the name.
1252          */
1253         for (lep = &ents[index];
1254              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
1255              lep++, index++) {
1256                 /*
1257                  * Skip over stale leaf entries.
1258                  */
1259                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1260                         continue;
1261                 /*
1262                  * Get the new data block number.
1263                  */
1264                 newdb = xfs_dir2_dataptr_to_db(args->geo,
1265                                                be32_to_cpu(lep->address));
1266                 /*
1267                  * If it's not the same as the old data block number,
1268                  * need to pitch the old one and read the new one.
1269                  */
1270                 if (newdb != curdb) {
1271                         if (dbp)
1272                                 xfs_trans_brelse(tp, dbp);
1273                         error = xfs_dir3_data_read(tp, dp,
1274                                            xfs_dir2_db_to_da(args->geo, newdb),
1275                                            -1, &dbp);
1276                         if (error) {
1277                                 xfs_trans_brelse(tp, lbp);
1278                                 return error;
1279                         }
1280                         curdb = newdb;
1281                 }
1282                 /*
1283                  * Point to the data entry.
1284                  */
1285                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1286                         xfs_dir2_dataptr_to_off(args->geo,
1287                                                 be32_to_cpu(lep->address)));
1288                 /*
1289                  * Compare name and if it's an exact match, return the index
1290                  * and buffer. If it's the first case-insensitive match, store
1291                  * the index and buffer and continue looking for an exact match.
1292                  */
1293                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1294                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1295                         args->cmpresult = cmp;
1296                         *indexp = index;
1297                         /* case exact match: return the current buffer. */
1298                         if (cmp == XFS_CMP_EXACT) {
1299                                 *dbpp = dbp;
1300                                 return 0;
1301                         }
1302                         cidb = curdb;
1303                 }
1304         }
1305         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1306         /*
1307          * Here, we can only be doing a lookup (not a rename or remove).
1308          * If a case-insensitive match was found earlier, re-read the
1309          * appropriate data block if required and return it.
1310          */
1311         if (args->cmpresult == XFS_CMP_CASE) {
1312                 ASSERT(cidb != -1);
1313                 if (cidb != curdb) {
1314                         xfs_trans_brelse(tp, dbp);
1315                         error = xfs_dir3_data_read(tp, dp,
1316                                            xfs_dir2_db_to_da(args->geo, cidb),
1317                                            -1, &dbp);
1318                         if (error) {
1319                                 xfs_trans_brelse(tp, lbp);
1320                                 return error;
1321                         }
1322                 }
1323                 *dbpp = dbp;
1324                 return 0;
1325         }
1326         /*
1327          * No match found, return -ENOENT.
1328          */
1329         ASSERT(cidb == -1);
1330         if (dbp)
1331                 xfs_trans_brelse(tp, dbp);
1332         xfs_trans_brelse(tp, lbp);
1333         return -ENOENT;
1334 }
1335
1336 /*
1337  * Remove an entry from a leaf format directory.
1338  */
1339 int                                             /* error */
1340 xfs_dir2_leaf_removename(
1341         xfs_da_args_t           *args)          /* operation arguments */
1342 {
1343         __be16                  *bestsp;        /* leaf block best freespace */
1344         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1345         xfs_dir2_db_t           db;             /* data block number */
1346         struct xfs_buf          *dbp;           /* data block buffer */
1347         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1348         xfs_inode_t             *dp;            /* incore directory inode */
1349         int                     error;          /* error return code */
1350         xfs_dir2_db_t           i;              /* temporary data block # */
1351         int                     index;          /* index into leaf entries */
1352         struct xfs_buf          *lbp;           /* leaf buffer */
1353         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1354         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1355         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1356         int                     needlog;        /* need to log data header */
1357         int                     needscan;       /* need to rescan data frees */
1358         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1359         struct xfs_dir2_data_free *bf;          /* bestfree table */
1360         struct xfs_dir2_leaf_entry *ents;
1361         struct xfs_dir3_icleaf_hdr leafhdr;
1362
1363         trace_xfs_dir2_leaf_removename(args);
1364
1365         /*
1366          * Lookup the leaf entry, get the leaf and data blocks read in.
1367          */
1368         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1369                 return error;
1370         }
1371         dp = args->dp;
1372         leaf = lbp->b_addr;
1373         hdr = dbp->b_addr;
1374         xfs_dir3_data_check(dp, dbp);
1375         bf = dp->d_ops->data_bestfree_p(hdr);
1376         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1377         ents = dp->d_ops->leaf_ents_p(leaf);
1378         /*
1379          * Point to the leaf entry, use that to point to the data entry.
1380          */
1381         lep = &ents[index];
1382         db = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address));
1383         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
1384                 xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1385         needscan = needlog = 0;
1386         oldbest = be16_to_cpu(bf[0].length);
1387         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1388         bestsp = xfs_dir2_leaf_bests_p(ltp);
1389         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1390         /*
1391          * Mark the former data entry unused.
1392          */
1393         xfs_dir2_data_make_free(args, dbp,
1394                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1395                 dp->d_ops->data_entsize(dep->namelen), &needlog, &needscan);
1396         /*
1397          * We just mark the leaf entry stale by putting a null in it.
1398          */
1399         leafhdr.stale++;
1400         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
1401         xfs_dir3_leaf_log_header(args, lbp);
1402
1403         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1404         xfs_dir3_leaf_log_ents(args, lbp, index, index);
1405
1406         /*
1407          * Scan the freespace in the data block again if necessary,
1408          * log the data block header if necessary.
1409          */
1410         if (needscan)
1411                 xfs_dir2_data_freescan(dp, hdr, &needlog);
1412         if (needlog)
1413                 xfs_dir2_data_log_header(args, dbp);
1414         /*
1415          * If the longest freespace in the data block has changed,
1416          * put the new value in the bests table and log that.
1417          */
1418         if (be16_to_cpu(bf[0].length) != oldbest) {
1419                 bestsp[db] = bf[0].length;
1420                 xfs_dir3_leaf_log_bests(args, lbp, db, db);
1421         }
1422         xfs_dir3_data_check(dp, dbp);
1423         /*
1424          * If the data block is now empty then get rid of the data block.
1425          */
1426         if (be16_to_cpu(bf[0].length) ==
1427                         args->geo->blksize - dp->d_ops->data_entry_offset) {
1428                 ASSERT(db != args->geo->datablk);
1429                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1430                         /*
1431                          * Nope, can't get rid of it because it caused
1432                          * allocation of a bmap btree block to do so.
1433                          * Just go on, returning success, leaving the
1434                          * empty block in place.
1435                          */
1436                         if (error == -ENOSPC && args->total == 0)
1437                                 error = 0;
1438                         xfs_dir3_leaf_check(dp, lbp);
1439                         return error;
1440                 }
1441                 dbp = NULL;
1442                 /*
1443                  * If this is the last data block then compact the
1444                  * bests table by getting rid of entries.
1445                  */
1446                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1447                         /*
1448                          * Look for the last active entry (i).
1449                          */
1450                         for (i = db - 1; i > 0; i--) {
1451                                 if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1452                                         break;
1453                         }
1454                         /*
1455                          * Copy the table down so inactive entries at the
1456                          * end are removed.
1457                          */
1458                         memmove(&bestsp[db - i], bestsp,
1459                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1460                         be32_add_cpu(&ltp->bestcount, -(db - i));
1461                         xfs_dir3_leaf_log_tail(args, lbp);
1462                         xfs_dir3_leaf_log_bests(args, lbp, 0,
1463                                                 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 != args->geo->datablk)
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(args->geo, 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(args, 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_trans_t             *tp;            /* transaction pointer */
1604
1605         dp = args->dp;
1606         tp = args->trans;
1607         /*
1608          * Read the offending data block.  We need its buffer.
1609          */
1610         error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(args->geo, db),
1611                                    -1, &dbp);
1612         if (error)
1613                 return error;
1614
1615         leaf = lbp->b_addr;
1616         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1617
1618 #ifdef DEBUG
1619 {
1620         struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
1621         struct xfs_dir2_data_free *bf = dp->d_ops->data_bestfree_p(hdr);
1622
1623         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1624                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1625         ASSERT(be16_to_cpu(bf[0].length) ==
1626                args->geo->blksize - dp->d_ops->data_entry_offset);
1627         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1628 }
1629 #endif
1630
1631         /*
1632          * Get rid of the data block.
1633          */
1634         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1635                 ASSERT(error != -ENOSPC);
1636                 xfs_trans_brelse(tp, dbp);
1637                 return error;
1638         }
1639         /*
1640          * Eliminate the last bests entry from the table.
1641          */
1642         bestsp = xfs_dir2_leaf_bests_p(ltp);
1643         be32_add_cpu(&ltp->bestcount, -1);
1644         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1645         xfs_dir3_leaf_log_tail(args, lbp);
1646         xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1647         return 0;
1648 }
1649
1650 static inline size_t
1651 xfs_dir3_leaf_size(
1652         struct xfs_dir3_icleaf_hdr      *hdr,
1653         int                             counts)
1654 {
1655         int     entries;
1656         int     hdrsize;
1657
1658         entries = hdr->count - hdr->stale;
1659         if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
1660             hdr->magic == XFS_DIR2_LEAFN_MAGIC)
1661                 hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
1662         else
1663                 hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
1664
1665         return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
1666                        + counts * sizeof(xfs_dir2_data_off_t)
1667                        + sizeof(xfs_dir2_leaf_tail_t);
1668 }
1669
1670 /*
1671  * Convert node form directory to leaf form directory.
1672  * The root of the node form dir needs to already be a LEAFN block.
1673  * Just return if we can't do anything.
1674  */
1675 int                                             /* error */
1676 xfs_dir2_node_to_leaf(
1677         xfs_da_state_t          *state)         /* directory operation state */
1678 {
1679         xfs_da_args_t           *args;          /* operation arguments */
1680         xfs_inode_t             *dp;            /* incore directory inode */
1681         int                     error;          /* error return code */
1682         struct xfs_buf          *fbp;           /* buffer for freespace block */
1683         xfs_fileoff_t           fo;             /* freespace file offset */
1684         xfs_dir2_free_t         *free;          /* freespace structure */
1685         struct xfs_buf          *lbp;           /* buffer for leaf block */
1686         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1687         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1688         xfs_mount_t             *mp;            /* filesystem mount point */
1689         int                     rval;           /* successful free trim? */
1690         xfs_trans_t             *tp;            /* transaction pointer */
1691         struct xfs_dir3_icleaf_hdr leafhdr;
1692         struct xfs_dir3_icfree_hdr freehdr;
1693
1694         /*
1695          * There's more than a leaf level in the btree, so there must
1696          * be multiple leafn blocks.  Give up.
1697          */
1698         if (state->path.active > 1)
1699                 return 0;
1700         args = state->args;
1701
1702         trace_xfs_dir2_node_to_leaf(args);
1703
1704         mp = state->mp;
1705         dp = args->dp;
1706         tp = args->trans;
1707         /*
1708          * Get the last offset in the file.
1709          */
1710         if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK))) {
1711                 return error;
1712         }
1713         fo -= args->geo->fsbcount;
1714         /*
1715          * If there are freespace blocks other than the first one,
1716          * take this opportunity to remove trailing empty freespace blocks
1717          * that may have been left behind during no-space-reservation
1718          * operations.
1719          */
1720         while (fo > args->geo->freeblk) {
1721                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1722                         return error;
1723                 }
1724                 if (rval)
1725                         fo -= args->geo->fsbcount;
1726                 else
1727                         return 0;
1728         }
1729         /*
1730          * Now find the block just before the freespace block.
1731          */
1732         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1733                 return error;
1734         }
1735         /*
1736          * If it's not the single leaf block, give up.
1737          */
1738         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + args->geo->blksize)
1739                 return 0;
1740         lbp = state->path.blk[0].bp;
1741         leaf = lbp->b_addr;
1742         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1743
1744         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
1745                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
1746
1747         /*
1748          * Read the freespace block.
1749          */
1750         error = xfs_dir2_free_read(tp, dp,  args->geo->freeblk, &fbp);
1751         if (error)
1752                 return error;
1753         free = fbp->b_addr;
1754         dp->d_ops->free_hdr_from_disk(&freehdr, free);
1755
1756         ASSERT(!freehdr.firstdb);
1757
1758         /*
1759          * Now see if the leafn and free data will fit in a leaf1.
1760          * If not, release the buffer and give up.
1761          */
1762         if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > args->geo->blksize) {
1763                 xfs_trans_brelse(tp, fbp);
1764                 return 0;
1765         }
1766
1767         /*
1768          * If the leaf has any stale entries in it, compress them out.
1769          */
1770         if (leafhdr.stale)
1771                 xfs_dir3_leaf_compact(args, &leafhdr, lbp);
1772
1773         lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
1774         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
1775         leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
1776                                         ? XFS_DIR2_LEAF1_MAGIC
1777                                         : XFS_DIR3_LEAF1_MAGIC;
1778
1779         /*
1780          * Set up the leaf tail from the freespace block.
1781          */
1782         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1783         ltp->bestcount = cpu_to_be32(freehdr.nvalid);
1784
1785         /*
1786          * Set up the leaf bests table.
1787          */
1788         memcpy(xfs_dir2_leaf_bests_p(ltp), dp->d_ops->free_bests_p(free),
1789                 freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
1790
1791         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
1792         xfs_dir3_leaf_log_header(args, lbp);
1793         xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1794         xfs_dir3_leaf_log_tail(args, lbp);
1795         xfs_dir3_leaf_check(dp, lbp);
1796
1797         /*
1798          * Get rid of the freespace block.
1799          */
1800         error = xfs_dir2_shrink_inode(args,
1801                         xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET),
1802                         fbp);
1803         if (error) {
1804                 /*
1805                  * This can't fail here because it can only happen when
1806                  * punching out the middle of an extent, and this is an
1807                  * isolated block.
1808                  */
1809                 ASSERT(error != -ENOSPC);
1810                 return error;
1811         }
1812         fbp = NULL;
1813         /*
1814          * Now see if we can convert the single-leaf directory
1815          * down to a block form directory.
1816          * This routine always kills the dabuf for the leaf, so
1817          * eliminate it from the path.
1818          */
1819         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1820         state->path.blk[0].bp = NULL;
1821         return error;
1822 }