fs/xfs/libxfs/xfs_dir2_leaf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   4  * Copyright (c) 2013 Red Hat, Inc.
   5  * All Rights Reserved.
   6  */
   7 #include "xfs.h"
   8 #include "xfs_fs.h"
   9 #include "xfs_shared.h"
  10 #include "xfs_format.h"
  11 #include "xfs_log_format.h"
  12 #include "xfs_trans_resv.h"
  13 #include "xfs_mount.h"
  14 #include "xfs_inode.h"
  15 #include "xfs_bmap.h"
  16 #include "xfs_dir2.h"
  17 #include "xfs_dir2_priv.h"
  18 #include "xfs_error.h"
  19 #include "xfs_trace.h"
  20 #include "xfs_trans.h"
  21 #include "xfs_buf_item.h"
  22
  23 /*
  24  * Local function declarations.
  25  */
  26 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
  27                                     int *indexp, struct xfs_buf **dbpp,
  28                                     struct xfs_dir3_icleaf_hdr *leafhdr);
  29 static void xfs_dir3_leaf_log_bests(struct xfs_da_args *args,
  30                                     struct xfs_buf *bp, int first, int last);
  31 static void xfs_dir3_leaf_log_tail(struct xfs_da_args *args,
  32                                    struct xfs_buf *bp);
  33
  34 void
  35 xfs_dir2_leaf_hdr_from_disk(
  36         struct xfs_mount                *mp,
  37         struct xfs_dir3_icleaf_hdr      *to,
  38         struct xfs_dir2_leaf            *from)
  39 {
  40         if (xfs_has_crc(mp)) {
  41                 struct xfs_dir3_leaf *from3 = (struct xfs_dir3_leaf *)from;
  42
  43                 to->forw = be32_to_cpu(from3->hdr.info.hdr.forw);
  44                 to->back = be32_to_cpu(from3->hdr.info.hdr.back);
  45                 to->magic = be16_to_cpu(from3->hdr.info.hdr.magic);
  46                 to->count = be16_to_cpu(from3->hdr.count);
  47                 to->stale = be16_to_cpu(from3->hdr.stale);
  48                 to->ents = from3->__ents;
  49
  50                 ASSERT(to->magic == XFS_DIR3_LEAF1_MAGIC ||
  51                        to->magic == XFS_DIR3_LEAFN_MAGIC);
  52         } else {
  53                 to->forw = be32_to_cpu(from->hdr.info.forw);
  54                 to->back = be32_to_cpu(from->hdr.info.back);
  55                 to->magic = be16_to_cpu(from->hdr.info.magic);
  56                 to->count = be16_to_cpu(from->hdr.count);
  57                 to->stale = be16_to_cpu(from->hdr.stale);
  58                 to->ents = from->__ents;
  59
  60                 ASSERT(to->magic == XFS_DIR2_LEAF1_MAGIC ||
  61                        to->magic == XFS_DIR2_LEAFN_MAGIC);
  62         }
  63 }
  64
  65 void
  66 xfs_dir2_leaf_hdr_to_disk(
  67         struct xfs_mount                *mp,
  68         struct xfs_dir2_leaf            *to,
  69         struct xfs_dir3_icleaf_hdr      *from)
  70 {
  71         if (xfs_has_crc(mp)) {
  72                 struct xfs_dir3_leaf *to3 = (struct xfs_dir3_leaf *)to;
  73
  74                 ASSERT(from->magic == XFS_DIR3_LEAF1_MAGIC ||
  75                        from->magic == XFS_DIR3_LEAFN_MAGIC);
  76
  77                 to3->hdr.info.hdr.forw = cpu_to_be32(from->forw);
  78                 to3->hdr.info.hdr.back = cpu_to_be32(from->back);
  79                 to3->hdr.info.hdr.magic = cpu_to_be16(from->magic);
  80                 to3->hdr.count = cpu_to_be16(from->count);
  81                 to3->hdr.stale = cpu_to_be16(from->stale);
  82         } else {
  83                 ASSERT(from->magic == XFS_DIR2_LEAF1_MAGIC ||
  84                        from->magic == XFS_DIR2_LEAFN_MAGIC);
  85
  86                 to->hdr.info.forw = cpu_to_be32(from->forw);
  87                 to->hdr.info.back = cpu_to_be32(from->back);
  88                 to->hdr.info.magic = cpu_to_be16(from->magic);
  89                 to->hdr.count = cpu_to_be16(from->count);
  90                 to->hdr.stale = cpu_to_be16(from->stale);
  91         }
  92 }
  93
  94 /*
  95  * Check the internal consistency of a leaf1 block.
  96  * Pop an assert if something is wrong.
  97  */
  98 #ifdef DEBUG
  99 static xfs_failaddr_t
 100 xfs_dir3_leaf1_check(
 101         struct xfs_inode        *dp,
 102         struct xfs_buf          *bp)
 103 {
 104         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 105         struct xfs_dir3_icleaf_hdr leafhdr;
 106
 107         xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 108
 109         if (leafhdr.magic == XFS_DIR3_LEAF1_MAGIC) {
 110                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 111                 if (be64_to_cpu(leaf3->info.blkno) != xfs_buf_daddr(bp))
 112                         return __this_address;
 113         } else if (leafhdr.magic != XFS_DIR2_LEAF1_MAGIC)
 114                 return __this_address;
 115
 116         return xfs_dir3_leaf_check_int(dp->i_mount, &leafhdr, leaf, false);
 117 }
 118
 119 static inline void
 120 xfs_dir3_leaf_check(
 121         struct xfs_inode        *dp,
 122         struct xfs_buf          *bp)
 123 {
 124         xfs_failaddr_t          fa;
 125
 126         fa = xfs_dir3_leaf1_check(dp, bp);
 127         if (!fa)
 128                 return;
 129         xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount,
 130                         bp->b_addr, BBTOB(bp->b_length), __FILE__, __LINE__,
 131                         fa);
 132         ASSERT(0);
 133 }
 134 #else
 135 #define xfs_dir3_leaf_check(dp, bp)
 136 #endif
 137
 138 xfs_failaddr_t
 139 xfs_dir3_leaf_check_int(
 140         struct xfs_mount                *mp,
 141         struct xfs_dir3_icleaf_hdr      *hdr,
 142         struct xfs_dir2_leaf            *leaf,
 143         bool                            expensive_checking)
 144 {
 145         struct xfs_da_geometry          *geo = mp->m_dir_geo;
 146         xfs_dir2_leaf_tail_t            *ltp;
 147         int                             stale;
 148         int                             i;
 149         bool                            isleaf1 = (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
 150                                                    hdr->magic == XFS_DIR3_LEAF1_MAGIC);
 151
 152         ltp = xfs_dir2_leaf_tail_p(geo, leaf);
 153
 154         /*
 155          * XXX (dgc): This value is not restrictive enough.
 156          * Should factor in the size of the bests table as well.
 157          * We can deduce a value for that from i_disk_size.
 158          */
 159         if (hdr->count > geo->leaf_max_ents)
 160                 return __this_address;
 161
 162         /* Leaves and bests don't overlap in leaf format. */
 163         if (isleaf1 &&
 164             (char *)&hdr->ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
 165                 return __this_address;
 166
 167         if (!expensive_checking)
 168                 return NULL;
 169
 170         /* Check hash value order, count stale entries.  */
 171         for (i = stale = 0; i < hdr->count; i++) {
 172                 if (i + 1 < hdr->count) {
 173                         if (be32_to_cpu(hdr->ents[i].hashval) >
 174                                         be32_to_cpu(hdr->ents[i + 1].hashval))
 175                                 return __this_address;
 176                 }
 177                 if (hdr->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 178                         stale++;
 179                 if (isleaf1 && xfs_dir2_dataptr_to_db(geo,
 180                                 be32_to_cpu(hdr->ents[i].address)) >=
 181                                 be32_to_cpu(ltp->bestcount))
 182                         return __this_address;
 183         }
 184         if (hdr->stale != stale)
 185                 return __this_address;
 186         return NULL;
 187 }
 188
 189 /*
 190  * We verify the magic numbers before decoding the leaf header so that on debug
 191  * kernels we don't get assertion failures in xfs_dir3_leaf_hdr_from_disk() due
 192  * to incorrect magic numbers.
 193  */
 194 static xfs_failaddr_t
 195 xfs_dir3_leaf_verify(
 196         struct xfs_buf                  *bp)
 197 {
 198         struct xfs_mount                *mp = bp->b_mount;
 199         struct xfs_dir3_icleaf_hdr      leafhdr;
 200         xfs_failaddr_t                  fa;
 201
 202         fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
 203         if (fa)
 204                 return fa;
 205
 206         xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, bp->b_addr);
 207         return xfs_dir3_leaf_check_int(mp, &leafhdr, bp->b_addr, true);
 208 }
 209
 210 static void
 211 xfs_dir3_leaf_read_verify(
 212         struct xfs_buf  *bp)
 213 {
 214         struct xfs_mount        *mp = bp->b_mount;
 215         xfs_failaddr_t          fa;
 216
 217         if (xfs_has_crc(mp) &&
 218              !xfs_buf_verify_cksum(bp, XFS_DIR3_LEAF_CRC_OFF))
 219                 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
 220         else {
 221                 fa = xfs_dir3_leaf_verify(bp);
 222                 if (fa)
 223                         xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 224         }
 225 }
 226
 227 static void
 228 xfs_dir3_leaf_write_verify(
 229         struct xfs_buf  *bp)
 230 {
 231         struct xfs_mount        *mp = bp->b_mount;
 232         struct xfs_buf_log_item *bip = bp->b_log_item;
 233         struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 234         xfs_failaddr_t          fa;
 235
 236         fa = xfs_dir3_leaf_verify(bp);
 237         if (fa) {
 238                 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 239                 return;
 240         }
 241
 242         if (!xfs_has_crc(mp))
 243                 return;
 244
 245         if (bip)
 246                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 247
 248         xfs_buf_update_cksum(bp, XFS_DIR3_LEAF_CRC_OFF);
 249 }
 250
 251 const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 252         .name = "xfs_dir3_leaf1",
 253         .magic16 = { cpu_to_be16(XFS_DIR2_LEAF1_MAGIC),
 254                      cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) },
 255         .verify_read = xfs_dir3_leaf_read_verify,
 256         .verify_write = xfs_dir3_leaf_write_verify,
 257         .verify_struct = xfs_dir3_leaf_verify,
 258 };
 259
 260 const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 261         .name = "xfs_dir3_leafn",
 262         .magic16 = { cpu_to_be16(XFS_DIR2_LEAFN_MAGIC),
 263                      cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) },
 264         .verify_read = xfs_dir3_leaf_read_verify,
 265         .verify_write = xfs_dir3_leaf_write_verify,
 266         .verify_struct = xfs_dir3_leaf_verify,
 267 };
 268
 269 int
 270 xfs_dir3_leaf_read(
 271         struct xfs_trans        *tp,
 272         struct xfs_inode        *dp,
 273         xfs_dablk_t             fbno,
 274         struct xfs_buf          **bpp)
 275 {
 276         int                     err;
 277
 278         err = xfs_da_read_buf(tp, dp, fbno, 0, bpp, XFS_DATA_FORK,
 279                         &xfs_dir3_leaf1_buf_ops);
 280         if (!err && tp && *bpp)
 281                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 282         return err;
 283 }
 284
 285 int
 286 xfs_dir3_leafn_read(
 287         struct xfs_trans        *tp,
 288         struct xfs_inode        *dp,
 289         xfs_dablk_t             fbno,
 290         struct xfs_buf          **bpp)
 291 {
 292         int                     err;
 293
 294         err = xfs_da_read_buf(tp, dp, fbno, 0, bpp, XFS_DATA_FORK,
 295                         &xfs_dir3_leafn_buf_ops);
 296         if (!err && tp && *bpp)
 297                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 298         return err;
 299 }
 300
 301 /*
 302  * Initialize a new leaf block, leaf1 or leafn magic accepted.
 303  */
 304 static void
 305 xfs_dir3_leaf_init(
 306         struct xfs_mount        *mp,
 307         struct xfs_trans        *tp,
 308         struct xfs_buf          *bp,
 309         xfs_ino_t               owner,
 310         uint16_t                type)
 311 {
 312         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 313
 314         ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 315
 316         if (xfs_has_crc(mp)) {
 317                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 318
 319                 memset(leaf3, 0, sizeof(*leaf3));
 320
 321                 leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 322                                          ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 323                                          : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 324                 leaf3->info.blkno = cpu_to_be64(xfs_buf_daddr(bp));
 325                 leaf3->info.owner = cpu_to_be64(owner);
 326                 uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_meta_uuid);
 327         } else {
 328                 memset(leaf, 0, sizeof(*leaf));
 329                 leaf->hdr.info.magic = cpu_to_be16(type);
 330         }
 331
 332         /*
 333          * If it's a leaf-format directory initialize the tail.
 334          * Caller is responsible for initialising the bests table.
 335          */
 336         if (type == XFS_DIR2_LEAF1_MAGIC) {
 337                 struct xfs_dir2_leaf_tail *ltp;
 338
 339                 ltp = xfs_dir2_leaf_tail_p(mp->m_dir_geo, leaf);
 340                 ltp->bestcount = 0;
 341                 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 342                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 343         } else {
 344                 bp->b_ops = &xfs_dir3_leafn_buf_ops;
 345                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 346         }
 347 }
 348
 349 int
 350 xfs_dir3_leaf_get_buf(
 351         xfs_da_args_t           *args,
 352         xfs_dir2_db_t           bno,
 353         struct xfs_buf          **bpp,
 354         uint16_t                magic)
 355 {
 356         struct xfs_inode        *dp = args->dp;
 357         struct xfs_trans        *tp = args->trans;
 358         struct xfs_mount        *mp = dp->i_mount;
 359         struct xfs_buf          *bp;
 360         int                     error;
 361
 362         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 363         ASSERT(bno >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET) &&
 364                bno < xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET));
 365
 366         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, bno),
 367                                &bp, XFS_DATA_FORK);
 368         if (error)
 369                 return error;
 370
 371         xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
 372         xfs_dir3_leaf_log_header(args, bp);
 373         if (magic == XFS_DIR2_LEAF1_MAGIC)
 374                 xfs_dir3_leaf_log_tail(args, bp);
 375         *bpp = bp;
 376         return 0;
 377 }
 378
 379 /*
 380  * Convert a block form directory to a leaf form directory.
 381  */
 382 int                                             /* error */
 383 xfs_dir2_block_to_leaf(
 384         xfs_da_args_t           *args,          /* operation arguments */
 385         struct xfs_buf          *dbp)           /* input block's buffer */
 386 {
 387         __be16                  *bestsp;        /* leaf's bestsp entries */
 388         xfs_dablk_t             blkno;          /* leaf block's bno */
 389         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 390         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
 391         xfs_dir2_block_tail_t   *btp;           /* block's tail */
 392         xfs_inode_t             *dp;            /* incore directory inode */
 393         int                     error;          /* error return code */
 394         struct xfs_buf          *lbp;           /* leaf block's buffer */
 395         xfs_dir2_db_t           ldb;            /* leaf block's bno */
 396         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 397         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
 398         int                     needlog;        /* need to log block header */
 399         int                     needscan;       /* need to rescan bestfree */
 400         xfs_trans_t             *tp;            /* transaction pointer */
 401         struct xfs_dir2_data_free *bf;
 402         struct xfs_dir3_icleaf_hdr leafhdr;
 403
 404         trace_xfs_dir2_block_to_leaf(args);
 405
 406         dp = args->dp;
 407         tp = args->trans;
 408         /*
 409          * Add the leaf block to the inode.
 410          * This interface will only put blocks in the leaf/node range.
 411          * Since that's empty now, we'll get the root (block 0 in range).
 412          */
 413         if ((error = xfs_da_grow_inode(args, &blkno))) {
 414                 return error;
 415         }
 416         ldb = xfs_dir2_da_to_db(args->geo, blkno);
 417         ASSERT(ldb == xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET));
 418         /*
 419          * Initialize the leaf block, get a buffer for it.
 420          */
 421         error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 422         if (error)
 423                 return error;
 424
 425         leaf = lbp->b_addr;
 426         hdr = dbp->b_addr;
 427         xfs_dir3_data_check(dp, dbp);
 428         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 429         blp = xfs_dir2_block_leaf_p(btp);
 430         bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 431
 432         /*
 433          * Set the counts in the leaf header.
 434          */
 435         xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 436         leafhdr.count = be32_to_cpu(btp->count);
 437         leafhdr.stale = be32_to_cpu(btp->stale);
 438         xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
 439         xfs_dir3_leaf_log_header(args, lbp);
 440
 441         /*
 442          * Could compact these but I think we always do the conversion
 443          * after squeezing out stale entries.
 444          */
 445         memcpy(leafhdr.ents, blp,
 446                 be32_to_cpu(btp->count) * sizeof(struct xfs_dir2_leaf_entry));
 447         xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, 0, leafhdr.count - 1);
 448         needscan = 0;
 449         needlog = 1;
 450         /*
 451          * Make the space formerly occupied by the leaf entries and block
 452          * tail be free.
 453          */
 454         xfs_dir2_data_make_free(args, dbp,
 455                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 456                 (xfs_dir2_data_aoff_t)((char *)hdr + args->geo->blksize -
 457                                        (char *)blp),
 458                 &needlog, &needscan);
 459         /*
 460          * Fix up the block header, make it a data block.
 461          */
 462         dbp->b_ops = &xfs_dir3_data_buf_ops;
 463         xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 464         if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 465                 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 466         else
 467                 hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 468
 469         if (needscan)
 470                 xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
 471         /*
 472          * Set up leaf tail and bests table.
 473          */
 474         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 475         ltp->bestcount = cpu_to_be32(1);
 476         bestsp = xfs_dir2_leaf_bests_p(ltp);
 477         bestsp[0] =  bf[0].length;
 478         /*
 479          * Log the data header and leaf bests table.
 480          */
 481         if (needlog)
 482                 xfs_dir2_data_log_header(args, dbp);
 483         xfs_dir3_leaf_check(dp, lbp);
 484         xfs_dir3_data_check(dp, dbp);
 485         xfs_dir3_leaf_log_bests(args, lbp, 0, 0);
 486         return 0;
 487 }
 488
 489 STATIC void
 490 xfs_dir3_leaf_find_stale(
 491         struct xfs_dir3_icleaf_hdr *leafhdr,
 492         struct xfs_dir2_leaf_entry *ents,
 493         int                     index,
 494         int                     *lowstale,
 495         int                     *highstale)
 496 {
 497         /*
 498          * Find the first stale entry before our index, if any.
 499          */
 500         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 501                 if (ents[*lowstale].address ==
 502                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 503                         break;
 504         }
 505
 506         /*
 507          * Find the first stale entry at or after our index, if any.
 508          * Stop if the result would require moving more entries than using
 509          * lowstale.
 510          */
 511         for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 512                 if (ents[*highstale].address ==
 513                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 514                         break;
 515                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 516                         break;
 517         }
 518 }
 519
 520 struct xfs_dir2_leaf_entry *
 521 xfs_dir3_leaf_find_entry(
 522         struct xfs_dir3_icleaf_hdr *leafhdr,
 523         struct xfs_dir2_leaf_entry *ents,
 524         int                     index,          /* leaf table position */
 525         int                     compact,        /* need to compact leaves */
 526         int                     lowstale,       /* index of prev stale leaf */
 527         int                     highstale,      /* index of next stale leaf */
 528         int                     *lfloglow,      /* low leaf logging index */
 529         int                     *lfloghigh)     /* high leaf logging index */
 530 {
 531         if (!leafhdr->stale) {
 532                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 533
 534                 /*
 535                  * Now we need to make room to insert the leaf entry.
 536                  *
 537                  * If there are no stale entries, just insert a hole at index.
 538                  */
 539                 lep = &ents[index];
 540                 if (index < leafhdr->count)
 541                         memmove(lep + 1, lep,
 542                                 (leafhdr->count - index) * sizeof(*lep));
 543
 544                 /*
 545                  * Record low and high logging indices for the leaf.
 546                  */
 547                 *lfloglow = index;
 548                 *lfloghigh = leafhdr->count++;
 549                 return lep;
 550         }
 551
 552         /*
 553          * There are stale entries.
 554          *
 555          * We will use one of them for the new entry.  It's probably not at
 556          * the right location, so we'll have to shift some up or down first.
 557          *
 558          * If we didn't compact before, we need to find the nearest stale
 559          * entries before and after our insertion point.
 560          */
 561         if (compact == 0)
 562                 xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 563                                          &lowstale, &highstale);
 564
 565         /*
 566          * If the low one is better, use it.
 567          */
 568         if (lowstale >= 0 &&
 569             (highstale == leafhdr->count ||
 570              index - lowstale - 1 < highstale - index)) {
 571                 ASSERT(index - lowstale - 1 >= 0);
 572                 ASSERT(ents[lowstale].address ==
 573                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 574
 575                 /*
 576                  * Copy entries up to cover the stale entry and make room
 577                  * for the new entry.
 578                  */
 579                 if (index - lowstale - 1 > 0) {
 580                         memmove(&ents[lowstale], &ents[lowstale + 1],
 581                                 (index - lowstale - 1) *
 582                                         sizeof(xfs_dir2_leaf_entry_t));
 583                 }
 584                 *lfloglow = min(lowstale, *lfloglow);
 585                 *lfloghigh = max(index - 1, *lfloghigh);
 586                 leafhdr->stale--;
 587                 return &ents[index - 1];
 588         }
 589
 590         /*
 591          * The high one is better, so use that one.
 592          */
 593         ASSERT(highstale - index >= 0);
 594         ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 595
 596         /*
 597          * Copy entries down to cover the stale entry and make room for the
 598          * new entry.
 599          */
 600         if (highstale - index > 0) {
 601                 memmove(&ents[index + 1], &ents[index],
 602                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 603         }
 604         *lfloglow = min(index, *lfloglow);
 605         *lfloghigh = max(highstale, *lfloghigh);
 606         leafhdr->stale--;
 607         return &ents[index];
 608 }
 609
 610 /*
 611  * Add an entry to a leaf form directory.
 612  */
 613 int                                             /* error */
 614 xfs_dir2_leaf_addname(
 615         struct xfs_da_args      *args)          /* operation arguments */
 616 {
 617         struct xfs_dir3_icleaf_hdr leafhdr;
 618         struct xfs_trans        *tp = args->trans;
 619         __be16                  *bestsp;        /* freespace table in leaf */
 620         __be16                  *tagp;          /* end of data entry */
 621         struct xfs_buf          *dbp;           /* data block buffer */
 622         struct xfs_buf          *lbp;           /* leaf's buffer */
 623         struct xfs_dir2_leaf    *leaf;          /* leaf structure */
 624         struct xfs_inode        *dp = args->dp; /* incore directory inode */
 625         struct xfs_dir2_data_hdr *hdr;          /* data block header */
 626         struct xfs_dir2_data_entry *dep;        /* data block entry */
 627         struct xfs_dir2_leaf_entry *lep;        /* leaf entry table pointer */
 628         struct xfs_dir2_leaf_entry *ents;
 629         struct xfs_dir2_data_unused *dup;       /* data unused entry */
 630         struct xfs_dir2_leaf_tail *ltp;         /* leaf tail pointer */
 631         struct xfs_dir2_data_free *bf;          /* bestfree table */
 632         int                     compact;        /* need to compact leaves */
 633         int                     error;          /* error return value */
 634         int                     grown;          /* allocated new data block */
 635         int                     highstale = 0;  /* index of next stale leaf */
 636         int                     i;              /* temporary, index */
 637         int                     index;          /* leaf table position */
 638         int                     length;         /* length of new entry */
 639         int                     lfloglow;       /* low leaf logging index */
 640         int                     lfloghigh;      /* high leaf logging index */
 641         int                     lowstale = 0;   /* index of prev stale leaf */
 642         int                     needbytes;      /* leaf block bytes needed */
 643         int                     needlog;        /* need to log data header */
 644         int                     needscan;       /* need to rescan data free */
 645         xfs_dir2_db_t           use_block;      /* data block number */
 646
 647         trace_xfs_dir2_leaf_addname(args);
 648
 649         error = xfs_dir3_leaf_read(tp, dp, args->geo->leafblk, &lbp);
 650         if (error)
 651                 return error;
 652
 653         /*
 654          * Look up the entry by hash value and name.
 655          * We know it's not there, our caller has already done a lookup.
 656          * So the index is of the entry to insert in front of.
 657          * But if there are dup hash values the index is of the first of those.
 658          */
 659         index = xfs_dir2_leaf_search_hash(args, lbp);
 660         leaf = lbp->b_addr;
 661         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 662         xfs_dir2_leaf_hdr_from_disk(dp->i_mount, &leafhdr, leaf);
 663         ents = leafhdr.ents;
 664         bestsp = xfs_dir2_leaf_bests_p(ltp);
 665         length = xfs_dir2_data_entsize(dp->i_mount, args->namelen);
 666
 667         /*
 668          * See if there are any entries with the same hash value
 669          * and space in their block for the new entry.
 670          * This is good because it puts multiple same-hash value entries
 671          * in a data block, improving the lookup of those entries.
 672          */
 673         for (use_block = -1, lep = &ents[index];
 674              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 675              index++, lep++) {
 676                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 677                         continue;
 678                 i = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address));
 679                 ASSERT(i < be32_to_cpu(ltp->bestcount));
 680                 ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 681                 if (be16_to_cpu(bestsp[i]) >= length) {
 682                         use_block = i;
 683                         break;
 684                 }
 685         }
 686         /*
 687          * Didn't find a block yet, linear search all the data blocks.
 688          */
 689         if (use_block == -1) {
 690                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 691                         /*
 692                          * Remember a block we see that's missing.
 693                          */
 694                         if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 695                             use_block == -1)
 696                                 use_block = i;
 697                         else if (be16_to_cpu(bestsp[i]) >= length) {
 698                                 use_block = i;
 699                                 break;
 700                         }
 701                 }
 702         }
 703         /*
 704          * How many bytes do we need in the leaf block?
 705          */
 706         needbytes = 0;
 707         if (!leafhdr.stale)
 708                 needbytes += sizeof(xfs_dir2_leaf_entry_t);
 709         if (use_block == -1)
 710                 needbytes += sizeof(xfs_dir2_data_off_t);
 711
 712         /*
 713          * Now kill use_block if it refers to a missing block, so we
 714          * can use it as an indication of allocation needed.
 715          */
 716         if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 717                 use_block = -1;
 718         /*
 719          * If we don't have enough free bytes but we can make enough
 720          * by compacting out stale entries, we'll do that.
 721          */
 722         if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
 723             leafhdr.stale > 1)
 724                 compact = 1;
 725
 726         /*
 727          * Otherwise if we don't have enough free bytes we need to
 728          * convert to node form.
 729          */
 730         else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
 731                 /*
 732                  * Just checking or no space reservation, give up.
 733                  */
 734                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 735                                                         args->total == 0) {
 736                         xfs_trans_brelse(tp, lbp);
 737                         return -ENOSPC;
 738                 }
 739                 /*
 740                  * Convert to node form.
 741                  */
 742                 error = xfs_dir2_leaf_to_node(args, lbp);
 743                 if (error)
 744                         return error;
 745                 /*
 746                  * Then add the new entry.
 747                  */
 748                 return xfs_dir2_node_addname(args);
 749         }
 750         /*
 751          * Otherwise it will fit without compaction.
 752          */
 753         else
 754                 compact = 0;
 755         /*
 756          * If just checking, then it will fit unless we needed to allocate
 757          * a new data block.
 758          */
 759         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 760                 xfs_trans_brelse(tp, lbp);
 761                 return use_block == -1 ? -ENOSPC : 0;
 762         }
 763         /*
 764          * If no allocations are allowed, return now before we've
 765          * changed anything.
 766          */
 767         if (args->total == 0 && use_block == -1) {
 768                 xfs_trans_brelse(tp, lbp);
 769                 return -ENOSPC;
 770         }
 771         /*
 772          * Need to compact the leaf entries, removing stale ones.
 773          * Leave one stale entry behind - the one closest to our
 774          * insertion index - and we'll shift that one to our insertion
 775          * point later.
 776          */
 777         if (compact) {
 778                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 779                         &highstale, &lfloglow, &lfloghigh);
 780         }
 781         /*
 782          * There are stale entries, so we'll need log-low and log-high
 783          * impossibly bad values later.
 784          */
 785         else if (leafhdr.stale) {
 786                 lfloglow = leafhdr.count;
 787                 lfloghigh = -1;
 788         }
 789         /*
 790          * If there was no data block space found, we need to allocate
 791          * a new one.
 792          */
 793         if (use_block == -1) {
 794                 /*
 795                  * Add the new data block.
 796                  */
 797                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 798                                 &use_block))) {
 799                         xfs_trans_brelse(tp, lbp);
 800                         return error;
 801                 }
 802                 /*
 803                  * Initialize the block.
 804                  */
 805                 if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
 806                         xfs_trans_brelse(tp, lbp);
 807                         return error;
 808                 }
 809                 /*
 810                  * If we're adding a new data block on the end we need to
 811                  * extend the bests table.  Copy it up one entry.
 812                  */
 813                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
 814                         bestsp--;
 815                         memmove(&bestsp[0], &bestsp[1],
 816                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 817                         be32_add_cpu(&ltp->bestcount, 1);
 818                         xfs_dir3_leaf_log_tail(args, lbp);
 819                         xfs_dir3_leaf_log_bests(args, lbp, 0,
 820                                                 be32_to_cpu(ltp->bestcount) - 1);
 821                 }
 822                 /*
 823                  * If we're filling in a previously empty block just log it.
 824                  */
 825                 else
 826                         xfs_dir3_leaf_log_bests(args, lbp, use_block, use_block);
 827                 hdr = dbp->b_addr;
 828                 bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 829                 bestsp[use_block] = bf[0].length;
 830                 grown = 1;
 831         } else {
 832                 /*
 833                  * Already had space in some data block.
 834                  * Just read that one in.
 835                  */
 836                 error = xfs_dir3_data_read(tp, dp,
 837                                    xfs_dir2_db_to_da(args->geo, use_block),
 838                                    0, &dbp);
 839                 if (error) {
 840                         xfs_trans_brelse(tp, lbp);
 841                         return error;
 842                 }
 843                 hdr = dbp->b_addr;
 844                 bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
 845                 grown = 0;
 846         }
 847         /*
 848          * Point to the biggest freespace in our data block.
 849          */
 850         dup = (xfs_dir2_data_unused_t *)
 851               ((char *)hdr + be16_to_cpu(bf[0].offset));
 852         needscan = needlog = 0;
 853         /*
 854          * Mark the initial part of our freespace in use for the new entry.
 855          */
 856         error = xfs_dir2_data_use_free(args, dbp, dup,
 857                         (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
 858                         length, &needlog, &needscan);
 859         if (error) {
 860                 xfs_trans_brelse(tp, lbp);
 861                 return error;
 862         }
 863         /*
 864          * Initialize our new entry (at last).
 865          */
 866         dep = (xfs_dir2_data_entry_t *)dup;
 867         dep->inumber = cpu_to_be64(args->inumber);
 868         dep->namelen = args->namelen;
 869         memcpy(dep->name, args->name, dep->namelen);
 870         xfs_dir2_data_put_ftype(dp->i_mount, dep, args->filetype);
 871         tagp = xfs_dir2_data_entry_tag_p(dp->i_mount, dep);
 872         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 873         /*
 874          * Need to scan fix up the bestfree table.
 875          */
 876         if (needscan)
 877                 xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
 878         /*
 879          * Need to log the data block's header.
 880          */
 881         if (needlog)
 882                 xfs_dir2_data_log_header(args, dbp);
 883         xfs_dir2_data_log_entry(args, dbp, dep);
 884         /*
 885          * If the bests table needs to be changed, do it.
 886          * Log the change unless we've already done that.
 887          */
 888         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
 889                 bestsp[use_block] = bf[0].length;
 890                 if (!grown)
 891                         xfs_dir3_leaf_log_bests(args, lbp, use_block, use_block);
 892         }
 893
 894         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 895                                        highstale, &lfloglow, &lfloghigh);
 896
 897         /*
 898          * Fill in the new leaf entry.
 899          */
 900         lep->hashval = cpu_to_be32(args->hashval);
 901         lep->address = cpu_to_be32(
 902                                 xfs_dir2_db_off_to_dataptr(args->geo, use_block,
 903                                 be16_to_cpu(*tagp)));
 904         /*
 905          * Log the leaf fields and give up the buffers.
 906          */
 907         xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
 908         xfs_dir3_leaf_log_header(args, lbp);
 909         xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, lfloglow, lfloghigh);
 910         xfs_dir3_leaf_check(dp, lbp);
 911         xfs_dir3_data_check(dp, dbp);
 912         return 0;
 913 }
 914
 915 /*
 916  * Compact out any stale entries in the leaf.
 917  * Log the header and changed leaf entries, if any.
 918  */
 919 void
 920 xfs_dir3_leaf_compact(
 921         xfs_da_args_t   *args,          /* operation arguments */
 922         struct xfs_dir3_icleaf_hdr *leafhdr,
 923         struct xfs_buf  *bp)            /* leaf buffer */
 924 {
 925         int             from;           /* source leaf index */
 926         xfs_dir2_leaf_t *leaf;          /* leaf structure */
 927         int             loglow;         /* first leaf entry to log */
 928         int             to;             /* target leaf index */
 929         struct xfs_inode *dp = args->dp;
 930
 931         leaf = bp->b_addr;
 932         if (!leafhdr->stale)
 933                 return;
 934
 935         /*
 936          * Compress out the stale entries in place.
 937          */
 938         for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 939                 if (leafhdr->ents[from].address ==
 940                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 941                         continue;
 942                 /*
 943                  * Only actually copy the entries that are different.
 944                  */
 945                 if (from > to) {
 946                         if (loglow == -1)
 947                                 loglow = to;
 948                         leafhdr->ents[to] = leafhdr->ents[from];
 949                 }
 950                 to++;
 951         }
 952         /*
 953          * Update and log the header, log the leaf entries.
 954          */
 955         ASSERT(leafhdr->stale == from - to);
 956         leafhdr->count -= leafhdr->stale;
 957         leafhdr->stale = 0;
 958
 959         xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, leafhdr);
 960         xfs_dir3_leaf_log_header(args, bp);
 961         if (loglow != -1)
 962                 xfs_dir3_leaf_log_ents(args, leafhdr, bp, loglow, to - 1);
 963 }
 964
 965 /*
 966  * Compact the leaf entries, removing stale ones.
 967  * Leave one stale entry behind - the one closest to our
 968  * insertion index - and the caller will shift that one to our insertion
 969  * point later.
 970  * Return new insertion index, where the remaining stale entry is,
 971  * and leaf logging indices.
 972  */
 973 void
 974 xfs_dir3_leaf_compact_x1(
 975         struct xfs_dir3_icleaf_hdr *leafhdr,
 976         struct xfs_dir2_leaf_entry *ents,
 977         int             *indexp,        /* insertion index */
 978         int             *lowstalep,     /* out: stale entry before us */
 979         int             *highstalep,    /* out: stale entry after us */
 980         int             *lowlogp,       /* out: low log index */
 981         int             *highlogp)      /* out: high log index */
 982 {
 983         int             from;           /* source copy index */
 984         int             highstale;      /* stale entry at/after index */
 985         int             index;          /* insertion index */
 986         int             keepstale;      /* source index of kept stale */
 987         int             lowstale;       /* stale entry before index */
 988         int             newindex=0;     /* new insertion index */
 989         int             to;             /* destination copy index */
 990
 991         ASSERT(leafhdr->stale > 1);
 992         index = *indexp;
 993
 994         xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
 995
 996         /*
 997          * Pick the better of lowstale and highstale.
 998          */
 999         if (lowstale >= 0 &&
1000             (highstale == leafhdr->count ||
1001              index - lowstale <= highstale - index))
1002                 keepstale = lowstale;
1003         else
1004                 keepstale = highstale;
1005         /*
1006          * Copy the entries in place, removing all the stale entries
1007          * except keepstale.
1008          */
1009         for (from = to = 0; from < leafhdr->count; from++) {
1010                 /*
1011                  * Notice the new value of index.
1012                  */
1013                 if (index == from)
1014                         newindex = to;
1015                 if (from != keepstale &&
1016                     ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1017                         if (from == to)
1018                                 *lowlogp = to;
1019                         continue;
1020                 }
1021                 /*
1022                  * Record the new keepstale value for the insertion.
1023                  */
1024                 if (from == keepstale)
1025                         lowstale = highstale = to;
1026                 /*
1027                  * Copy only the entries that have moved.
1028                  */
1029                 if (from > to)
1030                         ents[to] = ents[from];
1031                 to++;
1032         }
1033         ASSERT(from > to);
1034         /*
1035          * If the insertion point was past the last entry,
1036          * set the new insertion point accordingly.
1037          */
1038         if (index == from)
1039                 newindex = to;
1040         *indexp = newindex;
1041         /*
1042          * Adjust the leaf header values.
1043          */
1044         leafhdr->count -= from - to;
1045         leafhdr->stale = 1;
1046         /*
1047          * Remember the low/high stale value only in the "right"
1048          * direction.
1049          */
1050         if (lowstale >= newindex)
1051                 lowstale = -1;
1052         else
1053                 highstale = leafhdr->count;
1054         *highlogp = leafhdr->count - 1;
1055         *lowstalep = lowstale;
1056         *highstalep = highstale;
1057 }
1058
1059 /*
1060  * Log the bests entries indicated from a leaf1 block.
1061  */
1062 static void
1063 xfs_dir3_leaf_log_bests(
1064         struct xfs_da_args      *args,
1065         struct xfs_buf          *bp,            /* leaf buffer */
1066         int                     first,          /* first entry to log */
1067         int                     last)           /* last entry to log */
1068 {
1069         __be16                  *firstb;        /* pointer to first entry */
1070         __be16                  *lastb;         /* pointer to last entry */
1071         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1072         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1073
1074         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1075                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1076
1077         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1078         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1079         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1080         xfs_trans_log_buf(args->trans, bp,
1081                 (uint)((char *)firstb - (char *)leaf),
1082                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1083 }
1084
1085 /*
1086  * Log the leaf entries indicated from a leaf1 or leafn block.
1087  */
1088 void
1089 xfs_dir3_leaf_log_ents(
1090         struct xfs_da_args      *args,
1091         struct xfs_dir3_icleaf_hdr *hdr,
1092         struct xfs_buf          *bp,
1093         int                     first,
1094         int                     last)
1095 {
1096         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1097         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1098         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1099
1100         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1101                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1102                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1103                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1104
1105         firstlep = &hdr->ents[first];
1106         lastlep = &hdr->ents[last];
1107         xfs_trans_log_buf(args->trans, bp,
1108                 (uint)((char *)firstlep - (char *)leaf),
1109                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1110 }
1111
1112 /*
1113  * Log the header of the leaf1 or leafn block.
1114  */
1115 void
1116 xfs_dir3_leaf_log_header(
1117         struct xfs_da_args      *args,
1118         struct xfs_buf          *bp)
1119 {
1120         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1121
1122         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1123                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1124                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1125                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1126
1127         xfs_trans_log_buf(args->trans, bp,
1128                           (uint)((char *)&leaf->hdr - (char *)leaf),
1129                           args->geo->leaf_hdr_size - 1);
1130 }
1131
1132 /*
1133  * Log the tail of the leaf1 block.
1134  */
1135 STATIC void
1136 xfs_dir3_leaf_log_tail(
1137         struct xfs_da_args      *args,
1138         struct xfs_buf          *bp)
1139 {
1140         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1141         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1142
1143         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1144                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1145                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1146                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1147
1148         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1149         xfs_trans_log_buf(args->trans, bp, (uint)((char *)ltp - (char *)leaf),
1150                 (uint)(args->geo->blksize - 1));
1151 }
1152
1153 /*
1154  * Look up the entry referred to by args in the leaf format directory.
1155  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1156  * is also used by the node-format code.
1157  */
1158 int
1159 xfs_dir2_leaf_lookup(
1160         xfs_da_args_t           *args)          /* operation arguments */
1161 {
1162         struct xfs_buf          *dbp;           /* data block buffer */
1163         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1164         xfs_inode_t             *dp;            /* incore directory inode */
1165         int                     error;          /* error return code */
1166         int                     index;          /* found entry index */
1167         struct xfs_buf          *lbp;           /* leaf buffer */
1168         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1169         xfs_trans_t             *tp;            /* transaction pointer */
1170         struct xfs_dir3_icleaf_hdr leafhdr;
1171
1172         trace_xfs_dir2_leaf_lookup(args);
1173
1174         /*
1175          * Look up name in the leaf block, returning both buffers and index.
1176          */
1177         error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1178         if (error)
1179                 return error;
1180
1181         tp = args->trans;
1182         dp = args->dp;
1183         xfs_dir3_leaf_check(dp, lbp);
1184
1185         /*
1186          * Get to the leaf entry and contained data entry address.
1187          */
1188         lep = &leafhdr.ents[index];
1189
1190         /*
1191          * Point to the data entry.
1192          */
1193         dep = (xfs_dir2_data_entry_t *)
1194               ((char *)dbp->b_addr +
1195                xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1196         /*
1197          * Return the found inode number & CI name if appropriate
1198          */
1199         args->inumber = be64_to_cpu(dep->inumber);
1200         args->filetype = xfs_dir2_data_get_ftype(dp->i_mount, dep);
1201         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1202         xfs_trans_brelse(tp, dbp);
1203         xfs_trans_brelse(tp, lbp);
1204         return error;
1205 }
1206
1207 /*
1208  * Look up name/hash in the leaf block.
1209  * Fill in indexp with the found index, and dbpp with the data buffer.
1210  * If not found dbpp will be NULL, and ENOENT comes back.
1211  * lbpp will always be filled in with the leaf buffer unless there's an error.
1212  */
1213 static int                                      /* error */
1214 xfs_dir2_leaf_lookup_int(
1215         xfs_da_args_t           *args,          /* operation arguments */
1216         struct xfs_buf          **lbpp,         /* out: leaf buffer */
1217         int                     *indexp,        /* out: index in leaf block */
1218         struct xfs_buf          **dbpp,         /* out: data buffer */
1219         struct xfs_dir3_icleaf_hdr *leafhdr)
1220 {
1221         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1222         struct xfs_buf          *dbp = NULL;    /* data buffer */
1223         xfs_dir2_data_entry_t   *dep;           /* data entry */
1224         xfs_inode_t             *dp;            /* incore directory inode */
1225         int                     error;          /* error return code */
1226         int                     index;          /* index in leaf block */
1227         struct xfs_buf          *lbp;           /* leaf buffer */
1228         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1229         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1230         xfs_mount_t             *mp;            /* filesystem mount point */
1231         xfs_dir2_db_t           newdb;          /* new data block number */
1232         xfs_trans_t             *tp;            /* transaction pointer */
1233         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1234         enum xfs_dacmp          cmp;            /* name compare result */
1235
1236         dp = args->dp;
1237         tp = args->trans;
1238         mp = dp->i_mount;
1239
1240         error = xfs_dir3_leaf_read(tp, dp, args->geo->leafblk, &lbp);
1241         if (error)
1242                 return error;
1243
1244         *lbpp = lbp;
1245         leaf = lbp->b_addr;
1246         xfs_dir3_leaf_check(dp, lbp);
1247         xfs_dir2_leaf_hdr_from_disk(mp, leafhdr, leaf);
1248
1249         /*
1250          * Look for the first leaf entry with our hash value.
1251          */
1252         index = xfs_dir2_leaf_search_hash(args, lbp);
1253         /*
1254          * Loop over all the entries with the right hash value
1255          * looking to match the name.
1256          */
1257         for (lep = &leafhdr->ents[index];
1258              index < leafhdr->count &&
1259                         be32_to_cpu(lep->hashval) == args->hashval;
1260              lep++, index++) {
1261                 /*
1262                  * Skip over stale leaf entries.
1263                  */
1264                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1265                         continue;
1266                 /*
1267                  * Get the new data block number.
1268                  */
1269                 newdb = xfs_dir2_dataptr_to_db(args->geo,
1270                                                be32_to_cpu(lep->address));
1271                 /*
1272                  * If it's not the same as the old data block number,
1273                  * need to pitch the old one and read the new one.
1274                  */
1275                 if (newdb != curdb) {
1276                         if (dbp)
1277                                 xfs_trans_brelse(tp, dbp);
1278                         error = xfs_dir3_data_read(tp, dp,
1279                                            xfs_dir2_db_to_da(args->geo, newdb),
1280                                            0, &dbp);
1281                         if (error) {
1282                                 xfs_trans_brelse(tp, lbp);
1283                                 return error;
1284                         }
1285                         curdb = newdb;
1286                 }
1287                 /*
1288                  * Point to the data entry.
1289                  */
1290                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1291                         xfs_dir2_dataptr_to_off(args->geo,
1292                                                 be32_to_cpu(lep->address)));
1293                 /*
1294                  * Compare name and if it's an exact match, return the index
1295                  * and buffer. If it's the first case-insensitive match, store
1296                  * the index and buffer and continue looking for an exact match.
1297                  */
1298                 cmp = xfs_dir2_compname(args, dep->name, dep->namelen);
1299                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1300                         args->cmpresult = cmp;
1301                         *indexp = index;
1302                         /* case exact match: return the current buffer. */
1303                         if (cmp == XFS_CMP_EXACT) {
1304                                 *dbpp = dbp;
1305                                 return 0;
1306                         }
1307                         cidb = curdb;
1308                 }
1309         }
1310         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1311         /*
1312          * Here, we can only be doing a lookup (not a rename or remove).
1313          * If a case-insensitive match was found earlier, re-read the
1314          * appropriate data block if required and return it.
1315          */
1316         if (args->cmpresult == XFS_CMP_CASE) {
1317                 ASSERT(cidb != -1);
1318                 if (cidb != curdb) {
1319                         xfs_trans_brelse(tp, dbp);
1320                         error = xfs_dir3_data_read(tp, dp,
1321                                            xfs_dir2_db_to_da(args->geo, cidb),
1322                                            0, &dbp);
1323                         if (error) {
1324                                 xfs_trans_brelse(tp, lbp);
1325                                 return error;
1326                         }
1327                 }
1328                 *dbpp = dbp;
1329                 return 0;
1330         }
1331         /*
1332          * No match found, return -ENOENT.
1333          */
1334         ASSERT(cidb == -1);
1335         if (dbp)
1336                 xfs_trans_brelse(tp, dbp);
1337         xfs_trans_brelse(tp, lbp);
1338         return -ENOENT;
1339 }
1340
1341 /*
1342  * Remove an entry from a leaf format directory.
1343  */
1344 int                                             /* error */
1345 xfs_dir2_leaf_removename(
1346         xfs_da_args_t           *args)          /* operation arguments */
1347 {
1348         struct xfs_da_geometry  *geo = args->geo;
1349         __be16                  *bestsp;        /* leaf block best freespace */
1350         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1351         xfs_dir2_db_t           db;             /* data block number */
1352         struct xfs_buf          *dbp;           /* data block buffer */
1353         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1354         xfs_inode_t             *dp;            /* incore directory inode */
1355         int                     error;          /* error return code */
1356         xfs_dir2_db_t           i;              /* temporary data block # */
1357         int                     index;          /* index into leaf entries */
1358         struct xfs_buf          *lbp;           /* leaf buffer */
1359         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1360         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1361         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1362         int                     needlog;        /* need to log data header */
1363         int                     needscan;       /* need to rescan data frees */
1364         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1365         struct xfs_dir2_data_free *bf;          /* bestfree table */
1366         struct xfs_dir3_icleaf_hdr leafhdr;
1367
1368         trace_xfs_dir2_leaf_removename(args);
1369
1370         /*
1371          * Lookup the leaf entry, get the leaf and data blocks read in.
1372          */
1373         error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1374         if (error)
1375                 return error;
1376
1377         dp = args->dp;
1378         leaf = lbp->b_addr;
1379         hdr = dbp->b_addr;
1380         xfs_dir3_data_check(dp, dbp);
1381         bf = xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
1382
1383         /*
1384          * Point to the leaf entry, use that to point to the data entry.
1385          */
1386         lep = &leafhdr.ents[index];
1387         db = xfs_dir2_dataptr_to_db(geo, be32_to_cpu(lep->address));
1388         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
1389                 xfs_dir2_dataptr_to_off(geo, be32_to_cpu(lep->address)));
1390         needscan = needlog = 0;
1391         oldbest = be16_to_cpu(bf[0].length);
1392         ltp = xfs_dir2_leaf_tail_p(geo, leaf);
1393         bestsp = xfs_dir2_leaf_bests_p(ltp);
1394         if (be16_to_cpu(bestsp[db]) != oldbest) {
1395                 xfs_buf_mark_corrupt(lbp);
1396                 return -EFSCORRUPTED;
1397         }
1398         /*
1399          * Mark the former data entry unused.
1400          */
1401         xfs_dir2_data_make_free(args, dbp,
1402                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1403                 xfs_dir2_data_entsize(dp->i_mount, dep->namelen), &needlog,
1404                 &needscan);
1405         /*
1406          * We just mark the leaf entry stale by putting a null in it.
1407          */
1408         leafhdr.stale++;
1409         xfs_dir2_leaf_hdr_to_disk(dp->i_mount, leaf, &leafhdr);
1410         xfs_dir3_leaf_log_header(args, lbp);
1411
1412         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1413         xfs_dir3_leaf_log_ents(args, &leafhdr, lbp, index, index);
1414
1415         /*
1416          * Scan the freespace in the data block again if necessary,
1417          * log the data block header if necessary.
1418          */
1419         if (needscan)
1420                 xfs_dir2_data_freescan(dp->i_mount, hdr, &needlog);
1421         if (needlog)
1422                 xfs_dir2_data_log_header(args, dbp);
1423         /*
1424          * If the longest freespace in the data block has changed,
1425          * put the new value in the bests table and log that.
1426          */
1427         if (be16_to_cpu(bf[0].length) != oldbest) {
1428                 bestsp[db] = bf[0].length;
1429                 xfs_dir3_leaf_log_bests(args, lbp, db, db);
1430         }
1431         xfs_dir3_data_check(dp, dbp);
1432         /*
1433          * If the data block is now empty then get rid of the data block.
1434          */
1435         if (be16_to_cpu(bf[0].length) ==
1436             geo->blksize - geo->data_entry_offset) {
1437                 ASSERT(db != geo->datablk);
1438                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1439                         /*
1440                          * Nope, can't get rid of it because it caused
1441                          * allocation of a bmap btree block to do so.
1442                          * Just go on, returning success, leaving the
1443                          * empty block in place.
1444                          */
1445                         if (error == -ENOSPC && args->total == 0)
1446                                 error = 0;
1447                         xfs_dir3_leaf_check(dp, lbp);
1448                         return error;
1449                 }
1450                 dbp = NULL;
1451                 /*
1452                  * If this is the last data block then compact the
1453                  * bests table by getting rid of entries.
1454                  */
1455                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1456                         /*
1457                          * Look for the last active entry (i).
1458                          */
1459                         for (i = db - 1; i > 0; i--) {
1460                                 if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1461                                         break;
1462                         }
1463                         /*
1464                          * Copy the table down so inactive entries at the
1465                          * end are removed.
1466                          */
1467                         memmove(&bestsp[db - i], bestsp,
1468                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1469                         be32_add_cpu(&ltp->bestcount, -(db - i));
1470                         xfs_dir3_leaf_log_tail(args, lbp);
1471                         xfs_dir3_leaf_log_bests(args, lbp, 0,
1472                                                 be32_to_cpu(ltp->bestcount) - 1);
1473                 } else
1474                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1475         }
1476         /*
1477          * If the data block was not the first one, drop it.
1478          */
1479         else if (db != geo->datablk)
1480                 dbp = NULL;
1481
1482         xfs_dir3_leaf_check(dp, lbp);
1483         /*
1484          * See if we can convert to block form.
1485          */
1486         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1487 }
1488
1489 /*
1490  * Replace the inode number in a leaf format directory entry.
1491  */
1492 int                                             /* error */
1493 xfs_dir2_leaf_replace(
1494         xfs_da_args_t           *args)          /* operation arguments */
1495 {
1496         struct xfs_buf          *dbp;           /* data block buffer */
1497         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1498         xfs_inode_t             *dp;            /* incore directory inode */
1499         int                     error;          /* error return code */
1500         int                     index;          /* index of leaf entry */
1501         struct xfs_buf          *lbp;           /* leaf buffer */
1502         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1503         xfs_trans_t             *tp;            /* transaction pointer */
1504         struct xfs_dir3_icleaf_hdr leafhdr;
1505
1506         trace_xfs_dir2_leaf_replace(args);
1507
1508         /*
1509          * Look up the entry.
1510          */
1511         error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp, &leafhdr);
1512         if (error)
1513                 return error;
1514
1515         dp = args->dp;
1516         /*
1517          * Point to the leaf entry, get data address from it.
1518          */
1519         lep = &leafhdr.ents[index];
1520         /*
1521          * Point to the data entry.
1522          */
1523         dep = (xfs_dir2_data_entry_t *)
1524               ((char *)dbp->b_addr +
1525                xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address)));
1526         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1527         /*
1528          * Put the new inode number in, log it.
1529          */
1530         dep->inumber = cpu_to_be64(args->inumber);
1531         xfs_dir2_data_put_ftype(dp->i_mount, dep, args->filetype);
1532         tp = args->trans;
1533         xfs_dir2_data_log_entry(args, dbp, dep);
1534         xfs_dir3_leaf_check(dp, lbp);
1535         xfs_trans_brelse(tp, lbp);
1536         return 0;
1537 }
1538
1539 /*
1540  * Return index in the leaf block (lbp) which is either the first
1541  * one with this hash value, or if there are none, the insert point
1542  * for that hash value.
1543  */
1544 int                                             /* index value */
1545 xfs_dir2_leaf_search_hash(
1546         xfs_da_args_t           *args,          /* operation arguments */
1547         struct xfs_buf          *lbp)           /* leaf buffer */
1548 {
1549         xfs_dahash_t            hash=0;         /* hash from this entry */
1550         xfs_dahash_t            hashwant;       /* hash value looking for */
1551         int                     high;           /* high leaf index */
1552         int                     low;            /* low leaf index */
1553         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1554         int                     mid=0;          /* current leaf index */
1555         struct xfs_dir3_icleaf_hdr leafhdr;
1556
1557         xfs_dir2_leaf_hdr_from_disk(args->dp->i_mount, &leafhdr, lbp->b_addr);
1558
1559         /*
1560          * Note, the table cannot be empty, so we have to go through the loop.
1561          * Binary search the leaf entries looking for our hash value.
1562          */
1563         for (lep = leafhdr.ents, low = 0, high = leafhdr.count - 1,
1564                 hashwant = args->hashval;
1565              low <= high; ) {
1566                 mid = (low + high) >> 1;
1567                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1568                         break;
1569                 if (hash < hashwant)
1570                         low = mid + 1;
1571                 else
1572                         high = mid - 1;
1573         }
1574         /*
1575          * Found one, back up through all the equal hash values.
1576          */
1577         if (hash == hashwant) {
1578                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1579                         mid--;
1580                 }
1581         }
1582         /*
1583          * Need to point to an entry higher than ours.
1584          */
1585         else if (hash < hashwant)
1586                 mid++;
1587         return mid;
1588 }
1589
1590 /*
1591  * Trim off a trailing data block.  We know it's empty since the leaf
1592  * freespace table says so.
1593  */
1594 int                                             /* error */
1595 xfs_dir2_leaf_trim_data(
1596         xfs_da_args_t           *args,          /* operation arguments */
1597         struct xfs_buf          *lbp,           /* leaf buffer */
1598         xfs_dir2_db_t           db)             /* data block number */
1599 {
1600         struct xfs_da_geometry  *geo = args->geo;
1601         __be16                  *bestsp;        /* leaf bests table */
1602         struct xfs_buf          *dbp;           /* data block buffer */
1603         xfs_inode_t             *dp;            /* incore directory inode */
1604         int                     error;          /* error return value */
1605         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1606         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1607         xfs_trans_t             *tp;            /* transaction pointer */
1608
1609         dp = args->dp;
1610         tp = args->trans;
1611         /*
1612          * Read the offending data block.  We need its buffer.
1613          */
1614         error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(geo, db), 0, &dbp);
1615         if (error)
1616                 return error;
1617
1618         leaf = lbp->b_addr;
1619         ltp = xfs_dir2_leaf_tail_p(geo, leaf);
1620
1621 #ifdef DEBUG
1622 {
1623         struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
1624         struct xfs_dir2_data_free *bf =
1625                 xfs_dir2_data_bestfree_p(dp->i_mount, hdr);
1626
1627         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1628                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1629         ASSERT(be16_to_cpu(bf[0].length) ==
1630                geo->blksize - geo->data_entry_offset);
1631         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1632 }
1633 #endif
1634
1635         /*
1636          * Get rid of the data block.
1637          */
1638         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1639                 ASSERT(error != -ENOSPC);
1640                 xfs_trans_brelse(tp, dbp);
1641                 return error;
1642         }
1643         /*
1644          * Eliminate the last bests entry from the table.
1645          */
1646         bestsp = xfs_dir2_leaf_bests_p(ltp);
1647         be32_add_cpu(&ltp->bestcount, -1);
1648         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1649         xfs_dir3_leaf_log_tail(args, lbp);
1650         xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1651         return 0;
1652 }
1653
1654 static inline size_t
1655 xfs_dir3_leaf_size(
1656         struct xfs_dir3_icleaf_hdr      *hdr,
1657         int                             counts)
1658 {
1659         int     entries;
1660         int     hdrsize;
1661
1662         entries = hdr->count - hdr->stale;
1663         if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
1664             hdr->magic == XFS_DIR2_LEAFN_MAGIC)
1665                 hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
1666         else
1667                 hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
1668
1669         return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
1670                        + counts * sizeof(xfs_dir2_data_off_t)
1671                        + sizeof(xfs_dir2_leaf_tail_t);
1672 }
1673
1674 /*
1675  * Convert node form directory to leaf form directory.
1676  * The root of the node form dir needs to already be a LEAFN block.
1677  * Just return if we can't do anything.
1678  */
1679 int                                             /* error */
1680 xfs_dir2_node_to_leaf(
1681         xfs_da_state_t          *state)         /* directory operation state */
1682 {
1683         xfs_da_args_t           *args;          /* operation arguments */
1684         xfs_inode_t             *dp;            /* incore directory inode */
1685         int                     error;          /* error return code */
1686         struct xfs_buf          *fbp;           /* buffer for freespace block */
1687         xfs_fileoff_t           fo;             /* freespace file offset */
1688         struct xfs_buf          *lbp;           /* buffer for leaf block */
1689         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1690         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1691         xfs_mount_t             *mp;            /* filesystem mount point */
1692         int                     rval;           /* successful free trim? */
1693         xfs_trans_t             *tp;            /* transaction pointer */
1694         struct xfs_dir3_icleaf_hdr leafhdr;
1695         struct xfs_dir3_icfree_hdr freehdr;
1696
1697         /*
1698          * There's more than a leaf level in the btree, so there must
1699          * be multiple leafn blocks.  Give up.
1700          */
1701         if (state->path.active > 1)
1702                 return 0;
1703         args = state->args;
1704
1705         trace_xfs_dir2_node_to_leaf(args);
1706
1707         mp = state->mp;
1708         dp = args->dp;
1709         tp = args->trans;
1710         /*
1711          * Get the last offset in the file.
1712          */
1713         if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK))) {
1714                 return error;
1715         }
1716         fo -= args->geo->fsbcount;
1717         /*
1718          * If there are freespace blocks other than the first one,
1719          * take this opportunity to remove trailing empty freespace blocks
1720          * that may have been left behind during no-space-reservation
1721          * operations.
1722          */
1723         while (fo > args->geo->freeblk) {
1724                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1725                         return error;
1726                 }
1727                 if (rval)
1728                         fo -= args->geo->fsbcount;
1729                 else
1730                         return 0;
1731         }
1732         /*
1733          * Now find the block just before the freespace block.
1734          */
1735         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1736                 return error;
1737         }
1738         /*
1739          * If it's not the single leaf block, give up.
1740          */
1741         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + args->geo->blksize)
1742                 return 0;
1743         lbp = state->path.blk[0].bp;
1744         leaf = lbp->b_addr;
1745         xfs_dir2_leaf_hdr_from_disk(mp, &leafhdr, leaf);
1746
1747         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
1748                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
1749
1750         /*
1751          * Read the freespace block.
1752          */
1753         error = xfs_dir2_free_read(tp, dp,  args->geo->freeblk, &fbp);
1754         if (error)
1755                 return error;
1756         xfs_dir2_free_hdr_from_disk(mp, &freehdr, fbp->b_addr);
1757
1758         ASSERT(!freehdr.firstdb);
1759
1760         /*
1761          * Now see if the leafn and free data will fit in a leaf1.
1762          * If not, release the buffer and give up.
1763          */
1764         if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > args->geo->blksize) {
1765                 xfs_trans_brelse(tp, fbp);
1766                 return 0;
1767         }
1768
1769         /*
1770          * If the leaf has any stale entries in it, compress them out.
1771          */
1772         if (leafhdr.stale)
1773                 xfs_dir3_leaf_compact(args, &leafhdr, lbp);
1774
1775         lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
1776         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
1777         leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
1778                                         ? XFS_DIR2_LEAF1_MAGIC
1779                                         : XFS_DIR3_LEAF1_MAGIC;
1780
1781         /*
1782          * Set up the leaf tail from the freespace block.
1783          */
1784         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
1785         ltp->bestcount = cpu_to_be32(freehdr.nvalid);
1786
1787         /*
1788          * Set up the leaf bests table.
1789          */
1790         memcpy(xfs_dir2_leaf_bests_p(ltp), freehdr.bests,
1791                 freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
1792
1793         xfs_dir2_leaf_hdr_to_disk(mp, leaf, &leafhdr);
1794         xfs_dir3_leaf_log_header(args, lbp);
1795         xfs_dir3_leaf_log_bests(args, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1796         xfs_dir3_leaf_log_tail(args, lbp);
1797         xfs_dir3_leaf_check(dp, lbp);
1798
1799         /*
1800          * Get rid of the freespace block.
1801          */
1802         error = xfs_dir2_shrink_inode(args,
1803                         xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET),
1804                         fbp);
1805         if (error) {
1806                 /*
1807                  * This can't fail here because it can only happen when
1808                  * punching out the middle of an extent, and this is an
1809                  * isolated block.
1810                  */
1811                 ASSERT(error != -ENOSPC);
1812                 return error;
1813         }
1814         fbp = NULL;
1815         /*
1816          * Now see if we can convert the single-leaf directory
1817          * down to a block form directory.
1818          * This routine always kills the dabuf for the leaf, so
1819          * eliminate it from the path.
1820          */
1821         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1822         state->path.blk[0].bp = NULL;
1823         return error;
1824 }