Pileus Git - ~andy/linux/blob - 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_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
 184                                           XFS_DIR3_LEAF_CRC_OFF)) ||
 185             !xfs_dir3_leaf_verify(bp, magic)) {
 186                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 187                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 188         }
 189 }
 190
 191 static void
 192 __write_verify(
 193         struct xfs_buf  *bp,
 194         __uint16_t      magic)
 195 {
 196         struct xfs_mount        *mp = bp->b_target->bt_mount;
 197         struct xfs_buf_log_item *bip = bp->b_fspriv;
 198         struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 199
 200         if (!xfs_dir3_leaf_verify(bp, magic)) {
 201                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 202                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 203                 return;
 204         }
 205
 206         if (!xfs_sb_version_hascrc(&mp->m_sb))
 207                 return;
 208
 209         if (bip)
 210                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 211
 212         xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_LEAF_CRC_OFF);
 213 }
 214
 215 static void
 216 xfs_dir3_leaf1_read_verify(
 217         struct xfs_buf  *bp)
 218 {
 219         __read_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 220 }
 221
 222 static void
 223 xfs_dir3_leaf1_write_verify(
 224         struct xfs_buf  *bp)
 225 {
 226         __write_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 227 }
 228
 229 static void
 230 xfs_dir3_leafn_read_verify(
 231         struct xfs_buf  *bp)
 232 {
 233         __read_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 234 }
 235
 236 static void
 237 xfs_dir3_leafn_write_verify(
 238         struct xfs_buf  *bp)
 239 {
 240         __write_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 241 }
 242
 243 const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 244         .verify_read = xfs_dir3_leaf1_read_verify,
 245         .verify_write = xfs_dir3_leaf1_write_verify,
 246 };
 247
 248 const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 249         .verify_read = xfs_dir3_leafn_read_verify,
 250         .verify_write = xfs_dir3_leafn_write_verify,
 251 };
 252
 253 static int
 254 xfs_dir3_leaf_read(
 255         struct xfs_trans        *tp,
 256         struct xfs_inode        *dp,
 257         xfs_dablk_t             fbno,
 258         xfs_daddr_t             mappedbno,
 259         struct xfs_buf          **bpp)
 260 {
 261         int                     err;
 262
 263         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 264                                 XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
 265         if (!err && tp)
 266                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 267         return err;
 268 }
 269
 270 int
 271 xfs_dir3_leafn_read(
 272         struct xfs_trans        *tp,
 273         struct xfs_inode        *dp,
 274         xfs_dablk_t             fbno,
 275         xfs_daddr_t             mappedbno,
 276         struct xfs_buf          **bpp)
 277 {
 278         int                     err;
 279
 280         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 281                                 XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
 282         if (!err && tp)
 283                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 284         return err;
 285 }
 286
 287 /*
 288  * Initialize a new leaf block, leaf1 or leafn magic accepted.
 289  */
 290 static void
 291 xfs_dir3_leaf_init(
 292         struct xfs_mount        *mp,
 293         struct xfs_trans        *tp,
 294         struct xfs_buf          *bp,
 295         xfs_ino_t               owner,
 296         __uint16_t              type)
 297 {
 298         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 299
 300         ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 301
 302         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 303                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 304
 305                 memset(leaf3, 0, sizeof(*leaf3));
 306
 307                 leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 308                                          ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 309                                          : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 310                 leaf3->info.blkno = cpu_to_be64(bp->b_bn);
 311                 leaf3->info.owner = cpu_to_be64(owner);
 312                 uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_uuid);
 313         } else {
 314                 memset(leaf, 0, sizeof(*leaf));
 315                 leaf->hdr.info.magic = cpu_to_be16(type);
 316         }
 317
 318         /*
 319          * If it's a leaf-format directory initialize the tail.
 320          * Caller is responsible for initialising the bests table.
 321          */
 322         if (type == XFS_DIR2_LEAF1_MAGIC) {
 323                 struct xfs_dir2_leaf_tail *ltp;
 324
 325                 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 326                 ltp->bestcount = 0;
 327                 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 328                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 329         } else {
 330                 bp->b_ops = &xfs_dir3_leafn_buf_ops;
 331                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 332         }
 333 }
 334
 335 int
 336 xfs_dir3_leaf_get_buf(
 337         xfs_da_args_t           *args,
 338         xfs_dir2_db_t           bno,
 339         struct xfs_buf          **bpp,
 340         __uint16_t              magic)
 341 {
 342         struct xfs_inode        *dp = args->dp;
 343         struct xfs_trans        *tp = args->trans;
 344         struct xfs_mount        *mp = dp->i_mount;
 345         struct xfs_buf          *bp;
 346         int                     error;
 347
 348         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 349         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
 350                bno < XFS_DIR2_FREE_FIRSTDB(mp));
 351
 352         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
 353                                XFS_DATA_FORK);
 354         if (error)
 355                 return error;
 356
 357         xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
 358         xfs_dir3_leaf_log_header(tp, dp, bp);
 359         if (magic == XFS_DIR2_LEAF1_MAGIC)
 360                 xfs_dir3_leaf_log_tail(tp, bp);
 361         *bpp = bp;
 362         return 0;
 363 }
 364
 365 /*
 366  * Convert a block form directory to a leaf form directory.
 367  */
 368 int                                             /* error */
 369 xfs_dir2_block_to_leaf(
 370         xfs_da_args_t           *args,          /* operation arguments */
 371         struct xfs_buf          *dbp)           /* input block's buffer */
 372 {
 373         __be16                  *bestsp;        /* leaf's bestsp entries */
 374         xfs_dablk_t             blkno;          /* leaf block's bno */
 375         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 376         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
 377         xfs_dir2_block_tail_t   *btp;           /* block's tail */
 378         xfs_inode_t             *dp;            /* incore directory inode */
 379         int                     error;          /* error return code */
 380         struct xfs_buf          *lbp;           /* leaf block's buffer */
 381         xfs_dir2_db_t           ldb;            /* leaf block's bno */
 382         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 383         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
 384         xfs_mount_t             *mp;            /* filesystem mount point */
 385         int                     needlog;        /* need to log block header */
 386         int                     needscan;       /* need to rescan bestfree */
 387         xfs_trans_t             *tp;            /* transaction pointer */
 388         struct xfs_dir2_data_free *bf;
 389         struct xfs_dir2_leaf_entry *ents;
 390         struct xfs_dir3_icleaf_hdr leafhdr;
 391
 392         trace_xfs_dir2_block_to_leaf(args);
 393
 394         dp = args->dp;
 395         mp = dp->i_mount;
 396         tp = args->trans;
 397         /*
 398          * Add the leaf block to the inode.
 399          * This interface will only put blocks in the leaf/node range.
 400          * Since that's empty now, we'll get the root (block 0 in range).
 401          */
 402         if ((error = xfs_da_grow_inode(args, &blkno))) {
 403                 return error;
 404         }
 405         ldb = xfs_dir2_da_to_db(mp, blkno);
 406         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
 407         /*
 408          * Initialize the leaf block, get a buffer for it.
 409          */
 410         error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 411         if (error)
 412                 return error;
 413
 414         leaf = lbp->b_addr;
 415         hdr = dbp->b_addr;
 416         xfs_dir3_data_check(dp, dbp);
 417         btp = xfs_dir2_block_tail_p(mp, hdr);
 418         blp = xfs_dir2_block_leaf_p(btp);
 419         bf = dp->d_ops->data_bestfree_p(hdr);
 420         ents = dp->d_ops->leaf_ents_p(leaf);
 421
 422         /*
 423          * Set the counts in the leaf header.
 424          */
 425         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 426         leafhdr.count = be32_to_cpu(btp->count);
 427         leafhdr.stale = be32_to_cpu(btp->stale);
 428         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 429         xfs_dir3_leaf_log_header(tp, dp, lbp);
 430
 431         /*
 432          * Could compact these but I think we always do the conversion
 433          * after squeezing out stale entries.
 434          */
 435         memcpy(ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
 436         xfs_dir3_leaf_log_ents(tp, dp, lbp, 0, leafhdr.count - 1);
 437         needscan = 0;
 438         needlog = 1;
 439         /*
 440          * Make the space formerly occupied by the leaf entries and block
 441          * tail be free.
 442          */
 443         xfs_dir2_data_make_free(tp, dp, dbp,
 444                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 445                 (xfs_dir2_data_aoff_t)((char *)hdr + mp->m_dirblksize -
 446                                        (char *)blp),
 447                 &needlog, &needscan);
 448         /*
 449          * Fix up the block header, make it a data block.
 450          */
 451         dbp->b_ops = &xfs_dir3_data_buf_ops;
 452         xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 453         if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 454                 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 455         else
 456                 hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 457
 458         if (needscan)
 459                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 460         /*
 461          * Set up leaf tail and bests table.
 462          */
 463         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 464         ltp->bestcount = cpu_to_be32(1);
 465         bestsp = xfs_dir2_leaf_bests_p(ltp);
 466         bestsp[0] =  bf[0].length;
 467         /*
 468          * Log the data header and leaf bests table.
 469          */
 470         if (needlog)
 471                 xfs_dir2_data_log_header(tp, dp, dbp);
 472         xfs_dir3_leaf_check(dp, lbp);
 473         xfs_dir3_data_check(dp, dbp);
 474         xfs_dir3_leaf_log_bests(tp, lbp, 0, 0);
 475         return 0;
 476 }
 477
 478 STATIC void
 479 xfs_dir3_leaf_find_stale(
 480         struct xfs_dir3_icleaf_hdr *leafhdr,
 481         struct xfs_dir2_leaf_entry *ents,
 482         int                     index,
 483         int                     *lowstale,
 484         int                     *highstale)
 485 {
 486         /*
 487          * Find the first stale entry before our index, if any.
 488          */
 489         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 490                 if (ents[*lowstale].address ==
 491                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 492                         break;
 493         }
 494
 495         /*
 496          * Find the first stale entry at or after our index, if any.
 497          * Stop if the result would require moving more entries than using
 498          * lowstale.
 499          */
 500         for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 501                 if (ents[*highstale].address ==
 502                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 503                         break;
 504                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 505                         break;
 506         }
 507 }
 508
 509 struct xfs_dir2_leaf_entry *
 510 xfs_dir3_leaf_find_entry(
 511         struct xfs_dir3_icleaf_hdr *leafhdr,
 512         struct xfs_dir2_leaf_entry *ents,
 513         int                     index,          /* leaf table position */
 514         int                     compact,        /* need to compact leaves */
 515         int                     lowstale,       /* index of prev stale leaf */
 516         int                     highstale,      /* index of next stale leaf */
 517         int                     *lfloglow,      /* low leaf logging index */
 518         int                     *lfloghigh)     /* high leaf logging index */
 519 {
 520         if (!leafhdr->stale) {
 521                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 522
 523                 /*
 524                  * Now we need to make room to insert the leaf entry.
 525                  *
 526                  * If there are no stale entries, just insert a hole at index.
 527                  */
 528                 lep = &ents[index];
 529                 if (index < leafhdr->count)
 530                         memmove(lep + 1, lep,
 531                                 (leafhdr->count - index) * sizeof(*lep));
 532
 533                 /*
 534                  * Record low and high logging indices for the leaf.
 535                  */
 536                 *lfloglow = index;
 537                 *lfloghigh = leafhdr->count++;
 538                 return lep;
 539         }
 540
 541         /*
 542          * There are stale entries.
 543          *
 544          * We will use one of them for the new entry.  It's probably not at
 545          * the right location, so we'll have to shift some up or down first.
 546          *
 547          * If we didn't compact before, we need to find the nearest stale
 548          * entries before and after our insertion point.
 549          */
 550         if (compact == 0)
 551                 xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 552                                          &lowstale, &highstale);
 553
 554         /*
 555          * If the low one is better, use it.
 556          */
 557         if (lowstale >= 0 &&
 558             (highstale == leafhdr->count ||
 559              index - lowstale - 1 < highstale - index)) {
 560                 ASSERT(index - lowstale - 1 >= 0);
 561                 ASSERT(ents[lowstale].address ==
 562                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 563
 564                 /*
 565                  * Copy entries up to cover the stale entry and make room
 566                  * for the new entry.
 567                  */
 568                 if (index - lowstale - 1 > 0) {
 569                         memmove(&ents[lowstale], &ents[lowstale + 1],
 570                                 (index - lowstale - 1) *
 571                                         sizeof(xfs_dir2_leaf_entry_t));
 572                 }
 573                 *lfloglow = MIN(lowstale, *lfloglow);
 574                 *lfloghigh = MAX(index - 1, *lfloghigh);
 575                 leafhdr->stale--;
 576                 return &ents[index - 1];
 577         }
 578
 579         /*
 580          * The high one is better, so use that one.
 581          */
 582         ASSERT(highstale - index >= 0);
 583         ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 584
 585         /*
 586          * Copy entries down to cover the stale entry and make room for the
 587          * new entry.
 588          */
 589         if (highstale - index > 0) {
 590                 memmove(&ents[index + 1], &ents[index],
 591                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 592         }
 593         *lfloglow = MIN(index, *lfloglow);
 594         *lfloghigh = MAX(highstale, *lfloghigh);
 595         leafhdr->stale--;
 596         return &ents[index];
 597 }
 598
 599 /*
 600  * Add an entry to a leaf form directory.
 601  */
 602 int                                             /* error */
 603 xfs_dir2_leaf_addname(
 604         xfs_da_args_t           *args)          /* operation arguments */
 605 {
 606         __be16                  *bestsp;        /* freespace table in leaf */
 607         int                     compact;        /* need to compact leaves */
 608         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 609         struct xfs_buf          *dbp;           /* data block buffer */
 610         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 611         xfs_inode_t             *dp;            /* incore directory inode */
 612         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 613         int                     error;          /* error return value */
 614         int                     grown;          /* allocated new data block */
 615         int                     highstale;      /* index of next stale leaf */
 616         int                     i;              /* temporary, index */
 617         int                     index;          /* leaf table position */
 618         struct xfs_buf          *lbp;           /* leaf's buffer */
 619         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 620         int                     length;         /* length of new entry */
 621         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 622         int                     lfloglow;       /* low leaf logging index */
 623         int                     lfloghigh;      /* high leaf logging index */
 624         int                     lowstale;       /* index of prev stale leaf */
 625         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 626         xfs_mount_t             *mp;            /* filesystem mount point */
 627         int                     needbytes;      /* leaf block bytes needed */
 628         int                     needlog;        /* need to log data header */
 629         int                     needscan;       /* need to rescan data free */
 630         __be16                  *tagp;          /* end of data entry */
 631         xfs_trans_t             *tp;            /* transaction pointer */
 632         xfs_dir2_db_t           use_block;      /* data block number */
 633         struct xfs_dir2_data_free *bf;          /* bestfree table */
 634         struct xfs_dir2_leaf_entry *ents;
 635         struct xfs_dir3_icleaf_hdr leafhdr;
 636
 637         trace_xfs_dir2_leaf_addname(args);
 638
 639         dp = args->dp;
 640         tp = args->trans;
 641         mp = dp->i_mount;
 642
 643         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -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(mp, 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(mp, 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 XFS_ERROR(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 ? XFS_ERROR(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 XFS_ERROR(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(tp, lbp);
 813                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
 814                 }
 815                 /*
 816                  * If we're filling in a previously empty block just log it.
 817                  */
 818                 else
 819                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 820                 hdr = dbp->b_addr;
 821                 bf = dp->d_ops->data_bestfree_p(hdr);
 822                 bestsp[use_block] = bf[0].length;
 823                 grown = 1;
 824         } else {
 825                 /*
 826                  * Already had space in some data block.
 827                  * Just read that one in.
 828                  */
 829                 error = xfs_dir3_data_read(tp, dp,
 830                                            xfs_dir2_db_to_da(mp, use_block),
 831                                            -1, &dbp);
 832                 if (error) {
 833                         xfs_trans_brelse(tp, lbp);
 834                         return error;
 835                 }
 836                 hdr = dbp->b_addr;
 837                 bf = dp->d_ops->data_bestfree_p(hdr);
 838                 grown = 0;
 839         }
 840         /*
 841          * Point to the biggest freespace in our data block.
 842          */
 843         dup = (xfs_dir2_data_unused_t *)
 844               ((char *)hdr + be16_to_cpu(bf[0].offset));
 845         ASSERT(be16_to_cpu(dup->length) >= length);
 846         needscan = needlog = 0;
 847         /*
 848          * Mark the initial part of our freespace in use for the new entry.
 849          */
 850         xfs_dir2_data_use_free(tp, dp, dbp, dup,
 851                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
 852                 &needlog, &needscan);
 853         /*
 854          * Initialize our new entry (at last).
 855          */
 856         dep = (xfs_dir2_data_entry_t *)dup;
 857         dep->inumber = cpu_to_be64(args->inumber);
 858         dep->namelen = args->namelen;
 859         memcpy(dep->name, args->name, dep->namelen);
 860         dp->d_ops->data_put_ftype(dep, args->filetype);
 861         tagp = dp->d_ops->data_entry_tag_p(dep);
 862         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 863         /*
 864          * Need to scan fix up the bestfree table.
 865          */
 866         if (needscan)
 867                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 868         /*
 869          * Need to log the data block's header.
 870          */
 871         if (needlog)
 872                 xfs_dir2_data_log_header(tp, dp, dbp);
 873         xfs_dir2_data_log_entry(tp, dp, dbp, dep);
 874         /*
 875          * If the bests table needs to be changed, do it.
 876          * Log the change unless we've already done that.
 877          */
 878         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
 879                 bestsp[use_block] = bf[0].length;
 880                 if (!grown)
 881                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 882         }
 883
 884         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 885                                        highstale, &lfloglow, &lfloghigh);
 886
 887         /*
 888          * Fill in the new leaf entry.
 889          */
 890         lep->hashval = cpu_to_be32(args->hashval);
 891         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
 892                                 be16_to_cpu(*tagp)));
 893         /*
 894          * Log the leaf fields and give up the buffers.
 895          */
 896         dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 897         xfs_dir3_leaf_log_header(tp, dp, lbp);
 898         xfs_dir3_leaf_log_ents(tp, dp, lbp, lfloglow, lfloghigh);
 899         xfs_dir3_leaf_check(dp, lbp);
 900         xfs_dir3_data_check(dp, dbp);
 901         return 0;
 902 }
 903
 904 /*
 905  * Compact out any stale entries in the leaf.
 906  * Log the header and changed leaf entries, if any.
 907  */
 908 void
 909 xfs_dir3_leaf_compact(
 910         xfs_da_args_t   *args,          /* operation arguments */
 911         struct xfs_dir3_icleaf_hdr *leafhdr,
 912         struct xfs_buf  *bp)            /* leaf buffer */
 913 {
 914         int             from;           /* source leaf index */
 915         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 916         int             loglow;         /* first leaf entry to log */
 917         int             to;             /* target leaf index */
 918         struct xfs_dir2_leaf_entry *ents;
 919         struct xfs_inode *dp = args->dp;
 920
 921         leaf = bp->b_addr;
 922         if (!leafhdr->stale)
 923                 return;
 924
 925         /*
 926          * Compress out the stale entries in place.
 927          */
 928         ents = dp->d_ops->leaf_ents_p(leaf);
 929         for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 930                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 931                         continue;
 932                 /*
 933                  * Only actually copy the entries that are different.
 934                  */
 935                 if (from > to) {
 936                         if (loglow == -1)
 937                                 loglow = to;
 938                         ents[to] = ents[from];
 939                 }
 940                 to++;
 941         }
 942         /*
 943          * Update and log the header, log the leaf entries.
 944          */
 945         ASSERT(leafhdr->stale == from - to);
 946         leafhdr->count -= leafhdr->stale;
 947         leafhdr->stale = 0;
 948
 949         dp->d_ops->leaf_hdr_to_disk(leaf, leafhdr);
 950         xfs_dir3_leaf_log_header(args->trans, dp, bp);
 951         if (loglow != -1)
 952                 xfs_dir3_leaf_log_ents(args->trans, dp, bp, loglow, to - 1);
 953 }
 954
 955 /*
 956  * Compact the leaf entries, removing stale ones.
 957  * Leave one stale entry behind - the one closest to our
 958  * insertion index - and the caller will shift that one to our insertion
 959  * point later.
 960  * Return new insertion index, where the remaining stale entry is,
 961  * and leaf logging indices.
 962  */
 963 void
 964 xfs_dir3_leaf_compact_x1(
 965         struct xfs_dir3_icleaf_hdr *leafhdr,
 966         struct xfs_dir2_leaf_entry *ents,
 967         int             *indexp,        /* insertion index */
 968         int             *lowstalep,     /* out: stale entry before us */
 969         int             *highstalep,    /* out: stale entry after us */
 970         int             *lowlogp,       /* out: low log index */
 971         int             *highlogp)      /* out: high log index */
 972 {
 973         int             from;           /* source copy index */
 974         int             highstale;      /* stale entry at/after index */
 975         int             index;          /* insertion index */
 976         int             keepstale;      /* source index of kept stale */
 977         int             lowstale;       /* stale entry before index */
 978         int             newindex=0;     /* new insertion index */
 979         int             to;             /* destination copy index */
 980
 981         ASSERT(leafhdr->stale > 1);
 982         index = *indexp;
 983
 984         xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
 985
 986         /*
 987          * Pick the better of lowstale and highstale.
 988          */
 989         if (lowstale >= 0 &&
 990             (highstale == leafhdr->count ||
 991              index - lowstale <= highstale - index))
 992                 keepstale = lowstale;
 993         else
 994                 keepstale = highstale;
 995         /*
 996          * Copy the entries in place, removing all the stale entries
 997          * except keepstale.
 998          */
 999         for (from = to = 0; from < leafhdr->count; from++) {
1000                 /*
1001                  * Notice the new value of index.
1002                  */
1003                 if (index == from)
1004                         newindex = to;
1005                 if (from != keepstale &&
1006                     ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1007                         if (from == to)
1008                                 *lowlogp = to;
1009                         continue;
1010                 }
1011                 /*
1012                  * Record the new keepstale value for the insertion.
1013                  */
1014                 if (from == keepstale)
1015                         lowstale = highstale = to;
1016                 /*
1017                  * Copy only the entries that have moved.
1018                  */
1019                 if (from > to)
1020                         ents[to] = ents[from];
1021                 to++;
1022         }
1023         ASSERT(from > to);
1024         /*
1025          * If the insertion point was past the last entry,
1026          * set the new insertion point accordingly.
1027          */
1028         if (index == from)
1029                 newindex = to;
1030         *indexp = newindex;
1031         /*
1032          * Adjust the leaf header values.
1033          */
1034         leafhdr->count -= from - to;
1035         leafhdr->stale = 1;
1036         /*
1037          * Remember the low/high stale value only in the "right"
1038          * direction.
1039          */
1040         if (lowstale >= newindex)
1041                 lowstale = -1;
1042         else
1043                 highstale = leafhdr->count;
1044         *highlogp = leafhdr->count - 1;
1045         *lowstalep = lowstale;
1046         *highstalep = highstale;
1047 }
1048
1049 /*
1050  * Log the bests entries indicated from a leaf1 block.
1051  */
1052 static void
1053 xfs_dir3_leaf_log_bests(
1054         xfs_trans_t             *tp,            /* transaction pointer */
1055         struct xfs_buf          *bp,            /* leaf buffer */
1056         int                     first,          /* first entry to log */
1057         int                     last)           /* last entry to log */
1058 {
1059         __be16                  *firstb;        /* pointer to first entry */
1060         __be16                  *lastb;         /* pointer to last entry */
1061         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1062         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1063
1064         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1065                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1066
1067         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1068         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1069         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1070         xfs_trans_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1071                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1072 }
1073
1074 /*
1075  * Log the leaf entries indicated from a leaf1 or leafn block.
1076  */
1077 void
1078 xfs_dir3_leaf_log_ents(
1079         struct xfs_trans        *tp,
1080         struct xfs_inode        *dp,
1081         struct xfs_buf          *bp,
1082         int                     first,
1083         int                     last)
1084 {
1085         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1086         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1087         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1088         struct xfs_dir2_leaf_entry *ents;
1089
1090         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1091                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1092                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1093                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1094
1095         ents = dp->d_ops->leaf_ents_p(leaf);
1096         firstlep = &ents[first];
1097         lastlep = &ents[last];
1098         xfs_trans_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1099                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1100 }
1101
1102 /*
1103  * Log the header of the leaf1 or leafn block.
1104  */
1105 void
1106 xfs_dir3_leaf_log_header(
1107         struct xfs_trans        *tp,
1108         struct xfs_inode        *dp,
1109         struct xfs_buf          *bp)
1110 {
1111         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1112
1113         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1114                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1115                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1116                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1117
1118         xfs_trans_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1119                           dp->d_ops->leaf_hdr_size - 1);
1120 }
1121
1122 /*
1123  * Log the tail of the leaf1 block.
1124  */
1125 STATIC void
1126 xfs_dir3_leaf_log_tail(
1127         struct xfs_trans        *tp,
1128         struct xfs_buf          *bp)
1129 {
1130         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1131         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1132         struct xfs_mount        *mp = tp->t_mountp;
1133
1134         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1135                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1136                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1137                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1138
1139         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1140         xfs_trans_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1141                 (uint)(mp->m_dirblksize - 1));
1142 }
1143
1144 /*
1145  * Look up the entry referred to by args in the leaf format directory.
1146  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1147  * is also used by the node-format code.
1148  */
1149 int
1150 xfs_dir2_leaf_lookup(
1151         xfs_da_args_t           *args)          /* operation arguments */
1152 {
1153         struct xfs_buf          *dbp;           /* data block buffer */
1154         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1155         xfs_inode_t             *dp;            /* incore directory inode */
1156         int                     error;          /* error return code */
1157         int                     index;          /* found entry index */
1158         struct xfs_buf          *lbp;           /* leaf buffer */
1159         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1160         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1161         xfs_trans_t             *tp;            /* transaction pointer */
1162         struct xfs_dir2_leaf_entry *ents;
1163
1164         trace_xfs_dir2_leaf_lookup(args);
1165
1166         /*
1167          * Look up name in the leaf block, returning both buffers and index.
1168          */
1169         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1170                 return error;
1171         }
1172         tp = args->trans;
1173         dp = args->dp;
1174         xfs_dir3_leaf_check(dp, lbp);
1175         leaf = lbp->b_addr;
1176         ents = dp->d_ops->leaf_ents_p(leaf);
1177         /*
1178          * Get to the leaf entry and contained data entry address.
1179          */
1180         lep = &ents[index];
1181
1182         /*
1183          * Point to the data entry.
1184          */
1185         dep = (xfs_dir2_data_entry_t *)
1186               ((char *)dbp->b_addr +
1187                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1188         /*
1189          * Return the found inode number & CI name if appropriate
1190          */
1191         args->inumber = be64_to_cpu(dep->inumber);
1192         args->filetype = dp->d_ops->data_get_ftype(dep);
1193         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1194         xfs_trans_brelse(tp, dbp);
1195         xfs_trans_brelse(tp, lbp);
1196         return XFS_ERROR(error);
1197 }
1198
1199 /*
1200  * Look up name/hash in the leaf block.
1201  * Fill in indexp with the found index, and dbpp with the data buffer.
1202  * If not found dbpp will be NULL, and ENOENT comes back.
1203  * lbpp will always be filled in with the leaf buffer unless there's an error.
1204  */
1205 static int                                      /* error */
1206 xfs_dir2_leaf_lookup_int(
1207         xfs_da_args_t           *args,          /* operation arguments */
1208         struct xfs_buf          **lbpp,         /* out: leaf buffer */
1209         int                     *indexp,        /* out: index in leaf block */
1210         struct xfs_buf          **dbpp)         /* out: data buffer */
1211 {
1212         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1213         struct xfs_buf          *dbp = NULL;    /* data buffer */
1214         xfs_dir2_data_entry_t   *dep;           /* data entry */
1215         xfs_inode_t             *dp;            /* incore directory inode */
1216         int                     error;          /* error return code */
1217         int                     index;          /* index in leaf block */
1218         struct xfs_buf          *lbp;           /* leaf buffer */
1219         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1220         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1221         xfs_mount_t             *mp;            /* filesystem mount point */
1222         xfs_dir2_db_t           newdb;          /* new data block number */
1223         xfs_trans_t             *tp;            /* transaction pointer */
1224         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1225         enum xfs_dacmp          cmp;            /* name compare result */
1226         struct xfs_dir2_leaf_entry *ents;
1227         struct xfs_dir3_icleaf_hdr leafhdr;
1228
1229         dp = args->dp;
1230         tp = args->trans;
1231         mp = dp->i_mount;
1232
1233         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
1234         if (error)
1235                 return error;
1236
1237         *lbpp = lbp;
1238         leaf = lbp->b_addr;
1239         xfs_dir3_leaf_check(dp, lbp);
1240         ents = dp->d_ops->leaf_ents_p(leaf);
1241         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1242
1243         /*
1244          * Look for the first leaf entry with our hash value.
1245          */
1246         index = xfs_dir2_leaf_search_hash(args, lbp);
1247         /*
1248          * Loop over all the entries with the right hash value
1249          * looking to match the name.
1250          */
1251         for (lep = &ents[index];
1252              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
1253              lep++, index++) {
1254                 /*
1255                  * Skip over stale leaf entries.
1256                  */
1257                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1258                         continue;
1259                 /*
1260                  * Get the new data block number.
1261                  */
1262                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1263                 /*
1264                  * If it's not the same as the old data block number,
1265                  * need to pitch the old one and read the new one.
1266                  */
1267                 if (newdb != curdb) {
1268                         if (dbp)
1269                                 xfs_trans_brelse(tp, dbp);
1270                         error = xfs_dir3_data_read(tp, dp,
1271                                                    xfs_dir2_db_to_da(mp, newdb),
1272                                                    -1, &dbp);
1273                         if (error) {
1274                                 xfs_trans_brelse(tp, lbp);
1275                                 return error;
1276                         }
1277                         curdb = newdb;
1278                 }
1279                 /*
1280                  * Point to the data entry.
1281                  */
1282                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1283                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1284                 /*
1285                  * Compare name and if it's an exact match, return the index
1286                  * and buffer. If it's the first case-insensitive match, store
1287                  * the index and buffer and continue looking for an exact match.
1288                  */
1289                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1290                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1291                         args->cmpresult = cmp;
1292                         *indexp = index;
1293                         /* case exact match: return the current buffer. */
1294                         if (cmp == XFS_CMP_EXACT) {
1295                                 *dbpp = dbp;
1296                                 return 0;
1297                         }
1298                         cidb = curdb;
1299                 }
1300         }
1301         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1302         /*
1303          * Here, we can only be doing a lookup (not a rename or remove).
1304          * If a case-insensitive match was found earlier, re-read the
1305          * appropriate data block if required and return it.
1306          */
1307         if (args->cmpresult == XFS_CMP_CASE) {
1308                 ASSERT(cidb != -1);
1309                 if (cidb != curdb) {
1310                         xfs_trans_brelse(tp, dbp);
1311                         error = xfs_dir3_data_read(tp, dp,
1312                                                    xfs_dir2_db_to_da(mp, cidb),
1313                                                    -1, &dbp);
1314                         if (error) {
1315                                 xfs_trans_brelse(tp, lbp);
1316                                 return error;
1317                         }
1318                 }
1319                 *dbpp = dbp;
1320                 return 0;
1321         }
1322         /*
1323          * No match found, return ENOENT.
1324          */
1325         ASSERT(cidb == -1);
1326         if (dbp)
1327                 xfs_trans_brelse(tp, dbp);
1328         xfs_trans_brelse(tp, lbp);
1329         return XFS_ERROR(ENOENT);
1330 }
1331
1332 /*
1333  * Remove an entry from a leaf format directory.
1334  */
1335 int                                             /* error */
1336 xfs_dir2_leaf_removename(
1337         xfs_da_args_t           *args)          /* operation arguments */
1338 {
1339         __be16                  *bestsp;        /* leaf block best freespace */
1340         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1341         xfs_dir2_db_t           db;             /* data block number */
1342         struct xfs_buf          *dbp;           /* data block buffer */
1343         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1344         xfs_inode_t             *dp;            /* incore directory inode */
1345         int                     error;          /* error return code */
1346         xfs_dir2_db_t           i;              /* temporary data block # */
1347         int                     index;          /* index into leaf entries */
1348         struct xfs_buf          *lbp;           /* leaf buffer */
1349         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1350         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1351         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1352         xfs_mount_t             *mp;            /* filesystem mount point */
1353         int                     needlog;        /* need to log data header */
1354         int                     needscan;       /* need to rescan data frees */
1355         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1356         xfs_trans_t             *tp;            /* transaction pointer */
1357         struct xfs_dir2_data_free *bf;          /* bestfree table */
1358         struct xfs_dir2_leaf_entry *ents;
1359         struct xfs_dir3_icleaf_hdr leafhdr;
1360
1361         trace_xfs_dir2_leaf_removename(args);
1362
1363         /*
1364          * Lookup the leaf entry, get the leaf and data blocks read in.
1365          */
1366         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1367                 return error;
1368         }
1369         dp = args->dp;
1370         tp = args->trans;
1371         mp = dp->i_mount;
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(mp, be32_to_cpu(lep->address));
1383         dep = (xfs_dir2_data_entry_t *)
1384               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1385         needscan = needlog = 0;
1386         oldbest = be16_to_cpu(bf[0].length);
1387         ltp = xfs_dir2_leaf_tail_p(mp, 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(tp, dp, 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(tp, dp, lbp);
1402
1403         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1404         xfs_dir3_leaf_log_ents(tp, dp, 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(tp, dp, 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(tp, 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                         mp->m_dirblksize - dp->d_ops->data_entry_offset) {
1428                 ASSERT(db != mp->m_dirdatablk);
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(tp, lbp);
1462                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1463                 } else
1464                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1465         }
1466         /*
1467          * If the data block was not the first one, drop it.
1468          */
1469         else if (db != mp->m_dirdatablk)
1470                 dbp = NULL;
1471
1472         xfs_dir3_leaf_check(dp, lbp);
1473         /*
1474          * See if we can convert to block form.
1475          */
1476         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1477 }
1478
1479 /*
1480  * Replace the inode number in a leaf format directory entry.
1481  */
1482 int                                             /* error */
1483 xfs_dir2_leaf_replace(
1484         xfs_da_args_t           *args)          /* operation arguments */
1485 {
1486         struct xfs_buf          *dbp;           /* data block buffer */
1487         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1488         xfs_inode_t             *dp;            /* incore directory inode */
1489         int                     error;          /* error return code */
1490         int                     index;          /* index of leaf entry */
1491         struct xfs_buf          *lbp;           /* leaf buffer */
1492         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1493         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1494         xfs_trans_t             *tp;            /* transaction pointer */
1495         struct xfs_dir2_leaf_entry *ents;
1496
1497         trace_xfs_dir2_leaf_replace(args);
1498
1499         /*
1500          * Look up the entry.
1501          */
1502         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1503                 return error;
1504         }
1505         dp = args->dp;
1506         leaf = lbp->b_addr;
1507         ents = dp->d_ops->leaf_ents_p(leaf);
1508         /*
1509          * Point to the leaf entry, get data address from it.
1510          */
1511         lep = &ents[index];
1512         /*
1513          * Point to the data entry.
1514          */
1515         dep = (xfs_dir2_data_entry_t *)
1516               ((char *)dbp->b_addr +
1517                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1518         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1519         /*
1520          * Put the new inode number in, log it.
1521          */
1522         dep->inumber = cpu_to_be64(args->inumber);
1523         dp->d_ops->data_put_ftype(dep, args->filetype);
1524         tp = args->trans;
1525         xfs_dir2_data_log_entry(tp, dp, dbp, dep);
1526         xfs_dir3_leaf_check(dp, lbp);
1527         xfs_trans_brelse(tp, lbp);
1528         return 0;
1529 }
1530
1531 /*
1532  * Return index in the leaf block (lbp) which is either the first
1533  * one with this hash value, or if there are none, the insert point
1534  * for that hash value.
1535  */
1536 int                                             /* index value */
1537 xfs_dir2_leaf_search_hash(
1538         xfs_da_args_t           *args,          /* operation arguments */
1539         struct xfs_buf          *lbp)           /* leaf buffer */
1540 {
1541         xfs_dahash_t            hash=0;         /* hash from this entry */
1542         xfs_dahash_t            hashwant;       /* hash value looking for */
1543         int                     high;           /* high leaf index */
1544         int                     low;            /* low leaf index */
1545         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1546         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1547         int                     mid=0;          /* current leaf index */
1548         struct xfs_dir2_leaf_entry *ents;
1549         struct xfs_dir3_icleaf_hdr leafhdr;
1550
1551         leaf = lbp->b_addr;
1552         ents = args->dp->d_ops->leaf_ents_p(leaf);
1553         args->dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1554
1555         /*
1556          * Note, the table cannot be empty, so we have to go through the loop.
1557          * Binary search the leaf entries looking for our hash value.
1558          */
1559         for (lep = ents, low = 0, high = leafhdr.count - 1,
1560                 hashwant = args->hashval;
1561              low <= high; ) {
1562                 mid = (low + high) >> 1;
1563                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1564                         break;
1565                 if (hash < hashwant)
1566                         low = mid + 1;
1567                 else
1568                         high = mid - 1;
1569         }
1570         /*
1571          * Found one, back up through all the equal hash values.
1572          */
1573         if (hash == hashwant) {
1574                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1575                         mid--;
1576                 }
1577         }
1578         /*
1579          * Need to point to an entry higher than ours.
1580          */
1581         else if (hash < hashwant)
1582                 mid++;
1583         return mid;
1584 }
1585
1586 /*
1587  * Trim off a trailing data block.  We know it's empty since the leaf
1588  * freespace table says so.
1589  */
1590 int                                             /* error */
1591 xfs_dir2_leaf_trim_data(
1592         xfs_da_args_t           *args,          /* operation arguments */
1593         struct xfs_buf          *lbp,           /* leaf buffer */
1594         xfs_dir2_db_t           db)             /* data block number */
1595 {
1596         __be16                  *bestsp;        /* leaf bests table */
1597         struct xfs_buf          *dbp;           /* data block buffer */
1598         xfs_inode_t             *dp;            /* incore directory inode */
1599         int                     error;          /* error return value */
1600         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1601         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1602         xfs_mount_t             *mp;            /* filesystem mount point */
1603         xfs_trans_t             *tp;            /* transaction pointer */
1604
1605         dp = args->dp;
1606         mp = dp->i_mount;
1607         tp = args->trans;
1608         /*
1609          * Read the offending data block.  We need its buffer.
1610          */
1611         error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp);
1612         if (error)
1613                 return error;
1614
1615         leaf = lbp->b_addr;
1616         ltp = xfs_dir2_leaf_tail_p(mp, 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                mp->m_dirblksize - 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(tp, lbp);
1646         xfs_dir3_leaf_log_bests(tp, 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(tp, dp, &fo, XFS_DATA_FORK))) {
1711                 return error;
1712         }
1713         fo -= mp->m_dirblkfsbs;
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 > mp->m_dirfreeblk) {
1721                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1722                         return error;
1723                 }
1724                 if (rval)
1725                         fo -= mp->m_dirblkfsbs;
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 + mp->m_dirblksize)
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,  mp->m_dirfreeblk, &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) > mp->m_dirblksize) {
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(mp, 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(tp, dp, lbp);
1793         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1794         xfs_dir3_leaf_log_tail(tp, 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, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1801         if (error) {
1802                 /*
1803                  * This can't fail here because it can only happen when
1804                  * punching out the middle of an extent, and this is an
1805                  * isolated block.
1806                  */
1807                 ASSERT(error != ENOSPC);
1808                 return error;
1809         }
1810         fbp = NULL;
1811         /*
1812          * Now see if we can convert the single-leaf directory
1813          * down to a block form directory.
1814          * This routine always kills the dabuf for the leaf, so
1815          * eliminate it from the path.
1816          */
1817         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1818         state->path.blk[0].bp = NULL;
1819         return error;
1820 }