root/fs/xfs/libxfs/xfs_dir2_block.c

DEFINITIONS

1. xfs_dir_startup
2. xfs_dir3_block_verify
3. xfs_dir3_block_read_verify
4. xfs_dir3_block_write_verify
5. xfs_dir3_block_read
6. xfs_dir3_block_init
7. xfs_dir2_block_need_space
8. xfs_dir2_block_compact
9. xfs_dir2_block_addname
10. xfs_dir2_block_log_leaf
11. xfs_dir2_block_log_tail
12. xfs_dir2_block_lookup
13. xfs_dir2_block_lookup_int
14. xfs_dir2_block_removename
15. xfs_dir2_block_replace
16. xfs_dir2_block_sort
17. xfs_dir2_leaf_to_block
18. xfs_dir2_sf_to_block

   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_trans.h"
  16 #include "xfs_bmap.h"
  17 #include "xfs_buf_item.h"
  18 #include "xfs_dir2.h"
  19 #include "xfs_dir2_priv.h"
  20 #include "xfs_error.h"
  21 #include "xfs_trace.h"
  22 #include "xfs_log.h"
  23 
  24 /*
  25  * Local function prototypes.
  26  */
  27 static void xfs_dir2_block_log_leaf(xfs_trans_t *tp, struct xfs_buf *bp,
  28                                     int first, int last);
  29 static void xfs_dir2_block_log_tail(xfs_trans_t *tp, struct xfs_buf *bp);
  30 static int xfs_dir2_block_lookup_int(xfs_da_args_t *args, struct xfs_buf **bpp,
  31                                      int *entno);
  32 static int xfs_dir2_block_sort(const void *a, const void *b);
  33 
  34 static xfs_dahash_t xfs_dir_hash_dot, xfs_dir_hash_dotdot;
  35 
  36 /*
  37  * One-time startup routine called from xfs_init().
  38  */
  39 void
  40 xfs_dir_startup(void)
  41 {
  42         xfs_dir_hash_dot = xfs_da_hashname((unsigned char *)".", 1);
  43         xfs_dir_hash_dotdot = xfs_da_hashname((unsigned char *)"..", 2);
  44 }
  45 
  46 static xfs_failaddr_t
  47 xfs_dir3_block_verify(
  48         struct xfs_buf          *bp)
  49 {
  50         struct xfs_mount        *mp = bp->b_mount;
  51         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  52 
  53         if (!xfs_verify_magic(bp, hdr3->magic))
  54                 return __this_address;
  55 
  56         if (xfs_sb_version_hascrc(&mp->m_sb)) {
  57                 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
  58                         return __this_address;
  59                 if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
  60                         return __this_address;
  61                 if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
  62                         return __this_address;
  63         }
  64         return __xfs_dir3_data_check(NULL, bp);
  65 }
  66 
  67 static void
  68 xfs_dir3_block_read_verify(
  69         struct xfs_buf  *bp)
  70 {
  71         struct xfs_mount        *mp = bp->b_mount;
  72         xfs_failaddr_t          fa;
  73 
  74         if (xfs_sb_version_hascrc(&mp->m_sb) &&
  75              !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF))
  76                 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
  77         else {
  78                 fa = xfs_dir3_block_verify(bp);
  79                 if (fa)
  80                         xfs_verifier_error(bp, -EFSCORRUPTED, fa);
  81         }
  82 }
  83 
  84 static void
  85 xfs_dir3_block_write_verify(
  86         struct xfs_buf  *bp)
  87 {
  88         struct xfs_mount        *mp = bp->b_mount;
  89         struct xfs_buf_log_item *bip = bp->b_log_item;
  90         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  91         xfs_failaddr_t          fa;
  92 
  93         fa = xfs_dir3_block_verify(bp);
  94         if (fa) {
  95                 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
  96                 return;
  97         }
  98 
  99         if (!xfs_sb_version_hascrc(&mp->m_sb))
 100                 return;
 101 
 102         if (bip)
 103                 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
 104 
 105         xfs_buf_update_cksum(bp, XFS_DIR3_DATA_CRC_OFF);
 106 }
 107 
 108 const struct xfs_buf_ops xfs_dir3_block_buf_ops = {
 109         .name = "xfs_dir3_block",
 110         .magic = { cpu_to_be32(XFS_DIR2_BLOCK_MAGIC),
 111                    cpu_to_be32(XFS_DIR3_BLOCK_MAGIC) },
 112         .verify_read = xfs_dir3_block_read_verify,
 113         .verify_write = xfs_dir3_block_write_verify,
 114         .verify_struct = xfs_dir3_block_verify,
 115 };
 116 
 117 int
 118 xfs_dir3_block_read(
 119         struct xfs_trans        *tp,
 120         struct xfs_inode        *dp,
 121         struct xfs_buf          **bpp)
 122 {
 123         struct xfs_mount        *mp = dp->i_mount;
 124         int                     err;
 125 
 126         err = xfs_da_read_buf(tp, dp, mp->m_dir_geo->datablk, -1, bpp,
 127                                 XFS_DATA_FORK, &xfs_dir3_block_buf_ops);
 128         if (!err && tp && *bpp)
 129                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_BLOCK_BUF);
 130         return err;
 131 }
 132 
 133 static void
 134 xfs_dir3_block_init(
 135         struct xfs_mount        *mp,
 136         struct xfs_trans        *tp,
 137         struct xfs_buf          *bp,
 138         struct xfs_inode        *dp)
 139 {
 140         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 141 
 142         bp->b_ops = &xfs_dir3_block_buf_ops;
 143         xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_BLOCK_BUF);
 144 
 145         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 146                 memset(hdr3, 0, sizeof(*hdr3));
 147                 hdr3->magic = cpu_to_be32(XFS_DIR3_BLOCK_MAGIC);
 148                 hdr3->blkno = cpu_to_be64(bp->b_bn);
 149                 hdr3->owner = cpu_to_be64(dp->i_ino);
 150                 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
 151                 return;
 152 
 153         }
 154         hdr3->magic = cpu_to_be32(XFS_DIR2_BLOCK_MAGIC);
 155 }
 156 
 157 static void
 158 xfs_dir2_block_need_space(
 159         struct xfs_inode                *dp,
 160         struct xfs_dir2_data_hdr        *hdr,
 161         struct xfs_dir2_block_tail      *btp,
 162         struct xfs_dir2_leaf_entry      *blp,
 163         __be16                          **tagpp,
 164         struct xfs_dir2_data_unused     **dupp,
 165         struct xfs_dir2_data_unused     **enddupp,
 166         int                             *compact,
 167         int                             len)
 168 {
 169         struct xfs_dir2_data_free       *bf;
 170         __be16                          *tagp = NULL;
 171         struct xfs_dir2_data_unused     *dup = NULL;
 172         struct xfs_dir2_data_unused     *enddup = NULL;
 173 
 174         *compact = 0;
 175         bf = dp->d_ops->data_bestfree_p(hdr);
 176 
 177         /*
 178          * If there are stale entries we'll use one for the leaf.
 179          */
 180         if (btp->stale) {
 181                 if (be16_to_cpu(bf[0].length) >= len) {
 182                         /*
 183                          * The biggest entry enough to avoid compaction.
 184                          */
 185                         dup = (xfs_dir2_data_unused_t *)
 186                               ((char *)hdr + be16_to_cpu(bf[0].offset));
 187                         goto out;
 188                 }
 189 
 190                 /*
 191                  * Will need to compact to make this work.
 192                  * Tag just before the first leaf entry.
 193                  */
 194                 *compact = 1;
 195                 tagp = (__be16 *)blp - 1;
 196 
 197                 /* Data object just before the first leaf entry.  */
 198                 dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 199 
 200                 /*
 201                  * If it's not free then the data will go where the
 202                  * leaf data starts now, if it works at all.
 203                  */
 204                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 205                         if (be16_to_cpu(dup->length) + (be32_to_cpu(btp->stale) - 1) *
 206                             (uint)sizeof(*blp) < len)
 207                                 dup = NULL;
 208                 } else if ((be32_to_cpu(btp->stale) - 1) * (uint)sizeof(*blp) < len)
 209                         dup = NULL;
 210                 else
 211                         dup = (xfs_dir2_data_unused_t *)blp;
 212                 goto out;
 213         }
 214 
 215         /*
 216          * no stale entries, so just use free space.
 217          * Tag just before the first leaf entry.
 218          */
 219         tagp = (__be16 *)blp - 1;
 220 
 221         /* Data object just before the first leaf entry.  */
 222         enddup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 223 
 224         /*
 225          * If it's not free then can't do this add without cleaning up:
 226          * the space before the first leaf entry needs to be free so it
 227          * can be expanded to hold the pointer to the new entry.
 228          */
 229         if (be16_to_cpu(enddup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 230                 /*
 231                  * Check out the biggest freespace and see if it's the same one.
 232                  */
 233                 dup = (xfs_dir2_data_unused_t *)
 234                       ((char *)hdr + be16_to_cpu(bf[0].offset));
 235                 if (dup != enddup) {
 236                         /*
 237                          * Not the same free entry, just check its length.
 238                          */
 239                         if (be16_to_cpu(dup->length) < len)
 240                                 dup = NULL;
 241                         goto out;
 242                 }
 243 
 244                 /*
 245                  * It is the biggest freespace, can it hold the leaf too?
 246                  */
 247                 if (be16_to_cpu(dup->length) < len + (uint)sizeof(*blp)) {
 248                         /*
 249                          * Yes, use the second-largest entry instead if it works.
 250                          */
 251                         if (be16_to_cpu(bf[1].length) >= len)
 252                                 dup = (xfs_dir2_data_unused_t *)
 253                                       ((char *)hdr + be16_to_cpu(bf[1].offset));
 254                         else
 255                                 dup = NULL;
 256                 }
 257         }
 258 out:
 259         *tagpp = tagp;
 260         *dupp = dup;
 261         *enddupp = enddup;
 262 }
 263 
 264 /*
 265  * compact the leaf entries.
 266  * Leave the highest-numbered stale entry stale.
 267  * XXX should be the one closest to mid but mid is not yet computed.
 268  */
 269 static void
 270 xfs_dir2_block_compact(
 271         struct xfs_da_args              *args,
 272         struct xfs_buf                  *bp,
 273         struct xfs_dir2_data_hdr        *hdr,
 274         struct xfs_dir2_block_tail      *btp,
 275         struct xfs_dir2_leaf_entry      *blp,
 276         int                             *needlog,
 277         int                             *lfloghigh,
 278         int                             *lfloglow)
 279 {
 280         int                     fromidx;        /* source leaf index */
 281         int                     toidx;          /* target leaf index */
 282         int                     needscan = 0;
 283         int                     highstale;      /* high stale index */
 284 
 285         fromidx = toidx = be32_to_cpu(btp->count) - 1;
 286         highstale = *lfloghigh = -1;
 287         for (; fromidx >= 0; fromidx--) {
 288                 if (blp[fromidx].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
 289                         if (highstale == -1)
 290                                 highstale = toidx;
 291                         else {
 292                                 if (*lfloghigh == -1)
 293                                         *lfloghigh = toidx;
 294                                 continue;
 295                         }
 296                 }
 297                 if (fromidx < toidx)
 298                         blp[toidx] = blp[fromidx];
 299                 toidx--;
 300         }
 301         *lfloglow = toidx + 1 - (be32_to_cpu(btp->stale) - 1);
 302         *lfloghigh -= be32_to_cpu(btp->stale) - 1;
 303         be32_add_cpu(&btp->count, -(be32_to_cpu(btp->stale) - 1));
 304         xfs_dir2_data_make_free(args, bp,
 305                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 306                 (xfs_dir2_data_aoff_t)((be32_to_cpu(btp->stale) - 1) * sizeof(*blp)),
 307                 needlog, &needscan);
 308         btp->stale = cpu_to_be32(1);
 309         /*
 310          * If we now need to rebuild the bestfree map, do so.
 311          * This needs to happen before the next call to use_free.
 312          */
 313         if (needscan)
 314                 xfs_dir2_data_freescan(args->dp, hdr, needlog);
 315 }
 316 
 317 /*
 318  * Add an entry to a block directory.
 319  */
 320 int                                             /* error */
 321 xfs_dir2_block_addname(
 322         xfs_da_args_t           *args)          /* directory op arguments */
 323 {
 324         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 325         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 326         struct xfs_buf          *bp;            /* buffer for block */
 327         xfs_dir2_block_tail_t   *btp;           /* block tail */
 328         int                     compact;        /* need to compact leaf ents */
 329         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 330         xfs_inode_t             *dp;            /* directory inode */
 331         xfs_dir2_data_unused_t  *dup;           /* block unused entry */
 332         int                     error;          /* error return value */
 333         xfs_dir2_data_unused_t  *enddup=NULL;   /* unused at end of data */
 334         xfs_dahash_t            hash;           /* hash value of found entry */
 335         int                     high;           /* high index for binary srch */
 336         int                     highstale;      /* high stale index */
 337         int                     lfloghigh=0;    /* last final leaf to log */
 338         int                     lfloglow=0;     /* first final leaf to log */
 339         int                     len;            /* length of the new entry */
 340         int                     low;            /* low index for binary srch */
 341         int                     lowstale;       /* low stale index */
 342         int                     mid=0;          /* midpoint for binary srch */
 343         int                     needlog;        /* need to log header */
 344         int                     needscan;       /* need to rescan freespace */
 345         __be16                  *tagp;          /* pointer to tag value */
 346         xfs_trans_t             *tp;            /* transaction structure */
 347 
 348         trace_xfs_dir2_block_addname(args);
 349 
 350         dp = args->dp;
 351         tp = args->trans;
 352 
 353         /* Read the (one and only) directory block into bp. */
 354         error = xfs_dir3_block_read(tp, dp, &bp);
 355         if (error)
 356                 return error;
 357 
 358         len = dp->d_ops->data_entsize(args->namelen);
 359 
 360         /*
 361          * Set up pointers to parts of the block.
 362          */
 363         hdr = bp->b_addr;
 364         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 365         blp = xfs_dir2_block_leaf_p(btp);
 366 
 367         /*
 368          * Find out if we can reuse stale entries or whether we need extra
 369          * space for entry and new leaf.
 370          */
 371         xfs_dir2_block_need_space(dp, hdr, btp, blp, &tagp, &dup,
 372                                   &enddup, &compact, len);
 373 
 374         /*
 375          * Done everything we need for a space check now.
 376          */
 377         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 378                 xfs_trans_brelse(tp, bp);
 379                 if (!dup)
 380                         return -ENOSPC;
 381                 return 0;
 382         }
 383 
 384         /*
 385          * If we don't have space for the new entry & leaf ...
 386          */
 387         if (!dup) {
 388                 /* Don't have a space reservation: return no-space.  */
 389                 if (args->total == 0)
 390                         return -ENOSPC;
 391                 /*
 392                  * Convert to the next larger format.
 393                  * Then add the new entry in that format.
 394                  */
 395                 error = xfs_dir2_block_to_leaf(args, bp);
 396                 if (error)
 397                         return error;
 398                 return xfs_dir2_leaf_addname(args);
 399         }
 400 
 401         needlog = needscan = 0;
 402 
 403         /*
 404          * If need to compact the leaf entries, do it now.
 405          */
 406         if (compact) {
 407                 xfs_dir2_block_compact(args, bp, hdr, btp, blp, &needlog,
 408                                       &lfloghigh, &lfloglow);
 409                 /* recalculate blp post-compaction */
 410                 blp = xfs_dir2_block_leaf_p(btp);
 411         } else if (btp->stale) {
 412                 /*
 413                  * Set leaf logging boundaries to impossible state.
 414                  * For the no-stale case they're set explicitly.
 415                  */
 416                 lfloglow = be32_to_cpu(btp->count);
 417                 lfloghigh = -1;
 418         }
 419 
 420         /*
 421          * Find the slot that's first lower than our hash value, -1 if none.
 422          */
 423         for (low = 0, high = be32_to_cpu(btp->count) - 1; low <= high; ) {
 424                 mid = (low + high) >> 1;
 425                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 426                         break;
 427                 if (hash < args->hashval)
 428                         low = mid + 1;
 429                 else
 430                         high = mid - 1;
 431         }
 432         while (mid >= 0 && be32_to_cpu(blp[mid].hashval) >= args->hashval) {
 433                 mid--;
 434         }
 435         /*
 436          * No stale entries, will use enddup space to hold new leaf.
 437          */
 438         if (!btp->stale) {
 439                 xfs_dir2_data_aoff_t    aoff;
 440 
 441                 /*
 442                  * Mark the space needed for the new leaf entry, now in use.
 443                  */
 444                 aoff = (xfs_dir2_data_aoff_t)((char *)enddup - (char *)hdr +
 445                                 be16_to_cpu(enddup->length) - sizeof(*blp));
 446                 error = xfs_dir2_data_use_free(args, bp, enddup, aoff,
 447                                 (xfs_dir2_data_aoff_t)sizeof(*blp), &needlog,
 448                                 &needscan);
 449                 if (error)
 450                         return error;
 451 
 452                 /*
 453                  * Update the tail (entry count).
 454                  */
 455                 be32_add_cpu(&btp->count, 1);
 456                 /*
 457                  * If we now need to rebuild the bestfree map, do so.
 458                  * This needs to happen before the next call to use_free.
 459                  */
 460                 if (needscan) {
 461                         xfs_dir2_data_freescan(dp, hdr, &needlog);
 462                         needscan = 0;
 463                 }
 464                 /*
 465                  * Adjust pointer to the first leaf entry, we're about to move
 466                  * the table up one to open up space for the new leaf entry.
 467                  * Then adjust our index to match.
 468                  */
 469                 blp--;
 470                 mid++;
 471                 if (mid)
 472                         memmove(blp, &blp[1], mid * sizeof(*blp));
 473                 lfloglow = 0;
 474                 lfloghigh = mid;
 475         }
 476         /*
 477          * Use a stale leaf for our new entry.
 478          */
 479         else {
 480                 for (lowstale = mid;
 481                      lowstale >= 0 &&
 482                         blp[lowstale].address !=
 483                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 484                      lowstale--)
 485                         continue;
 486                 for (highstale = mid + 1;
 487                      highstale < be32_to_cpu(btp->count) &&
 488                         blp[highstale].address !=
 489                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR) &&
 490                         (lowstale < 0 || mid - lowstale > highstale - mid);
 491                      highstale++)
 492                         continue;
 493                 /*
 494                  * Move entries toward the low-numbered stale entry.
 495                  */
 496                 if (lowstale >= 0 &&
 497                     (highstale == be32_to_cpu(btp->count) ||
 498                      mid - lowstale <= highstale - mid)) {
 499                         if (mid - lowstale)
 500                                 memmove(&blp[lowstale], &blp[lowstale + 1],
 501                                         (mid - lowstale) * sizeof(*blp));
 502                         lfloglow = min(lowstale, lfloglow);
 503                         lfloghigh = max(mid, lfloghigh);
 504                 }
 505                 /*
 506                  * Move entries toward the high-numbered stale entry.
 507                  */
 508                 else {
 509                         ASSERT(highstale < be32_to_cpu(btp->count));
 510                         mid++;
 511                         if (highstale - mid)
 512                                 memmove(&blp[mid + 1], &blp[mid],
 513                                         (highstale - mid) * sizeof(*blp));
 514                         lfloglow = min(mid, lfloglow);
 515                         lfloghigh = max(highstale, lfloghigh);
 516                 }
 517                 be32_add_cpu(&btp->stale, -1);
 518         }
 519         /*
 520          * Point to the new data entry.
 521          */
 522         dep = (xfs_dir2_data_entry_t *)dup;
 523         /*
 524          * Fill in the leaf entry.
 525          */
 526         blp[mid].hashval = cpu_to_be32(args->hashval);
 527         blp[mid].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(
 528                                 (char *)dep - (char *)hdr));
 529         xfs_dir2_block_log_leaf(tp, bp, lfloglow, lfloghigh);
 530         /*
 531          * Mark space for the data entry used.
 532          */
 533         error = xfs_dir2_data_use_free(args, bp, dup,
 534                         (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
 535                         (xfs_dir2_data_aoff_t)len, &needlog, &needscan);
 536         if (error)
 537                 return error;
 538         /*
 539          * Create the new data entry.
 540          */
 541         dep->inumber = cpu_to_be64(args->inumber);
 542         dep->namelen = args->namelen;
 543         memcpy(dep->name, args->name, args->namelen);
 544         dp->d_ops->data_put_ftype(dep, args->filetype);
 545         tagp = dp->d_ops->data_entry_tag_p(dep);
 546         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 547         /*
 548          * Clean up the bestfree array and log the header, tail, and entry.
 549          */
 550         if (needscan)
 551                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 552         if (needlog)
 553                 xfs_dir2_data_log_header(args, bp);
 554         xfs_dir2_block_log_tail(tp, bp);
 555         xfs_dir2_data_log_entry(args, bp, dep);
 556         xfs_dir3_data_check(dp, bp);
 557         return 0;
 558 }
 559 
 560 /*
 561  * Log leaf entries from the block.
 562  */
 563 static void
 564 xfs_dir2_block_log_leaf(
 565         xfs_trans_t             *tp,            /* transaction structure */
 566         struct xfs_buf          *bp,            /* block buffer */
 567         int                     first,          /* index of first logged leaf */
 568         int                     last)           /* index of last logged leaf */
 569 {
 570         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 571         xfs_dir2_leaf_entry_t   *blp;
 572         xfs_dir2_block_tail_t   *btp;
 573 
 574         btp = xfs_dir2_block_tail_p(tp->t_mountp->m_dir_geo, hdr);
 575         blp = xfs_dir2_block_leaf_p(btp);
 576         xfs_trans_log_buf(tp, bp, (uint)((char *)&blp[first] - (char *)hdr),
 577                 (uint)((char *)&blp[last + 1] - (char *)hdr - 1));
 578 }
 579 
 580 /*
 581  * Log the block tail.
 582  */
 583 static void
 584 xfs_dir2_block_log_tail(
 585         xfs_trans_t             *tp,            /* transaction structure */
 586         struct xfs_buf          *bp)            /* block buffer */
 587 {
 588         xfs_dir2_data_hdr_t     *hdr = bp->b_addr;
 589         xfs_dir2_block_tail_t   *btp;
 590 
 591         btp = xfs_dir2_block_tail_p(tp->t_mountp->m_dir_geo, hdr);
 592         xfs_trans_log_buf(tp, bp, (uint)((char *)btp - (char *)hdr),
 593                 (uint)((char *)(btp + 1) - (char *)hdr - 1));
 594 }
 595 
 596 /*
 597  * Look up an entry in the block.  This is the external routine,
 598  * xfs_dir2_block_lookup_int does the real work.
 599  */
 600 int                                             /* error */
 601 xfs_dir2_block_lookup(
 602         xfs_da_args_t           *args)          /* dir lookup arguments */
 603 {
 604         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 605         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 606         struct xfs_buf          *bp;            /* block buffer */
 607         xfs_dir2_block_tail_t   *btp;           /* block tail */
 608         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 609         xfs_inode_t             *dp;            /* incore inode */
 610         int                     ent;            /* entry index */
 611         int                     error;          /* error return value */
 612 
 613         trace_xfs_dir2_block_lookup(args);
 614 
 615         /*
 616          * Get the buffer, look up the entry.
 617          * If not found (ENOENT) then return, have no buffer.
 618          */
 619         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent)))
 620                 return error;
 621         dp = args->dp;
 622         hdr = bp->b_addr;
 623         xfs_dir3_data_check(dp, bp);
 624         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 625         blp = xfs_dir2_block_leaf_p(btp);
 626         /*
 627          * Get the offset from the leaf entry, to point to the data.
 628          */
 629         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
 630                         xfs_dir2_dataptr_to_off(args->geo,
 631                                                 be32_to_cpu(blp[ent].address)));
 632         /*
 633          * Fill in inode number, CI name if appropriate, release the block.
 634          */
 635         args->inumber = be64_to_cpu(dep->inumber);
 636         args->filetype = dp->d_ops->data_get_ftype(dep);
 637         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
 638         xfs_trans_brelse(args->trans, bp);
 639         return error;
 640 }
 641 
 642 /*
 643  * Internal block lookup routine.
 644  */
 645 static int                                      /* error */
 646 xfs_dir2_block_lookup_int(
 647         xfs_da_args_t           *args,          /* dir lookup arguments */
 648         struct xfs_buf          **bpp,          /* returned block buffer */
 649         int                     *entno)         /* returned entry number */
 650 {
 651         xfs_dir2_dataptr_t      addr;           /* data entry address */
 652         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 653         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 654         struct xfs_buf          *bp;            /* block buffer */
 655         xfs_dir2_block_tail_t   *btp;           /* block tail */
 656         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 657         xfs_inode_t             *dp;            /* incore inode */
 658         int                     error;          /* error return value */
 659         xfs_dahash_t            hash;           /* found hash value */
 660         int                     high;           /* binary search high index */
 661         int                     low;            /* binary search low index */
 662         int                     mid;            /* binary search current idx */
 663         xfs_mount_t             *mp;            /* filesystem mount point */
 664         xfs_trans_t             *tp;            /* transaction pointer */
 665         enum xfs_dacmp          cmp;            /* comparison result */
 666 
 667         dp = args->dp;
 668         tp = args->trans;
 669         mp = dp->i_mount;
 670 
 671         error = xfs_dir3_block_read(tp, dp, &bp);
 672         if (error)
 673                 return error;
 674 
 675         hdr = bp->b_addr;
 676         xfs_dir3_data_check(dp, bp);
 677         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 678         blp = xfs_dir2_block_leaf_p(btp);
 679         /*
 680          * Loop doing a binary search for our hash value.
 681          * Find our entry, ENOENT if it's not there.
 682          */
 683         for (low = 0, high = be32_to_cpu(btp->count) - 1; ; ) {
 684                 ASSERT(low <= high);
 685                 mid = (low + high) >> 1;
 686                 if ((hash = be32_to_cpu(blp[mid].hashval)) == args->hashval)
 687                         break;
 688                 if (hash < args->hashval)
 689                         low = mid + 1;
 690                 else
 691                         high = mid - 1;
 692                 if (low > high) {
 693                         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 694                         xfs_trans_brelse(tp, bp);
 695                         return -ENOENT;
 696                 }
 697         }
 698         /*
 699          * Back up to the first one with the right hash value.
 700          */
 701         while (mid > 0 && be32_to_cpu(blp[mid - 1].hashval) == args->hashval) {
 702                 mid--;
 703         }
 704         /*
 705          * Now loop forward through all the entries with the
 706          * right hash value looking for our name.
 707          */
 708         do {
 709                 if ((addr = be32_to_cpu(blp[mid].address)) == XFS_DIR2_NULL_DATAPTR)
 710                         continue;
 711                 /*
 712                  * Get pointer to the entry from the leaf.
 713                  */
 714                 dep = (xfs_dir2_data_entry_t *)
 715                         ((char *)hdr + xfs_dir2_dataptr_to_off(args->geo, addr));
 716                 /*
 717                  * Compare name and if it's an exact match, return the index
 718                  * and buffer. If it's the first case-insensitive match, store
 719                  * the index and buffer and continue looking for an exact match.
 720                  */
 721                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 722                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 723                         args->cmpresult = cmp;
 724                         *bpp = bp;
 725                         *entno = mid;
 726                         if (cmp == XFS_CMP_EXACT)
 727                                 return 0;
 728                 }
 729         } while (++mid < be32_to_cpu(btp->count) &&
 730                         be32_to_cpu(blp[mid].hashval) == hash);
 731 
 732         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 733         /*
 734          * Here, we can only be doing a lookup (not a rename or replace).
 735          * If a case-insensitive match was found earlier, return success.
 736          */
 737         if (args->cmpresult == XFS_CMP_CASE)
 738                 return 0;
 739         /*
 740          * No match, release the buffer and return ENOENT.
 741          */
 742         xfs_trans_brelse(tp, bp);
 743         return -ENOENT;
 744 }
 745 
 746 /*
 747  * Remove an entry from a block format directory.
 748  * If that makes the block small enough to fit in shortform, transform it.
 749  */
 750 int                                             /* error */
 751 xfs_dir2_block_removename(
 752         xfs_da_args_t           *args)          /* directory operation args */
 753 {
 754         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 755         xfs_dir2_leaf_entry_t   *blp;           /* block leaf pointer */
 756         struct xfs_buf          *bp;            /* block buffer */
 757         xfs_dir2_block_tail_t   *btp;           /* block tail */
 758         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 759         xfs_inode_t             *dp;            /* incore inode */
 760         int                     ent;            /* block leaf entry index */
 761         int                     error;          /* error return value */
 762         int                     needlog;        /* need to log block header */
 763         int                     needscan;       /* need to fixup bestfree */
 764         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 765         int                     size;           /* shortform size */
 766         xfs_trans_t             *tp;            /* transaction pointer */
 767 
 768         trace_xfs_dir2_block_removename(args);
 769 
 770         /*
 771          * Look up the entry in the block.  Gets the buffer and entry index.
 772          * It will always be there, the vnodeops level does a lookup first.
 773          */
 774         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 775                 return error;
 776         }
 777         dp = args->dp;
 778         tp = args->trans;
 779         hdr = bp->b_addr;
 780         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 781         blp = xfs_dir2_block_leaf_p(btp);
 782         /*
 783          * Point to the data entry using the leaf entry.
 784          */
 785         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
 786                         xfs_dir2_dataptr_to_off(args->geo,
 787                                                 be32_to_cpu(blp[ent].address)));
 788         /*
 789          * Mark the data entry's space free.
 790          */
 791         needlog = needscan = 0;
 792         xfs_dir2_data_make_free(args, bp,
 793                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
 794                 dp->d_ops->data_entsize(dep->namelen), &needlog, &needscan);
 795         /*
 796          * Fix up the block tail.
 797          */
 798         be32_add_cpu(&btp->stale, 1);
 799         xfs_dir2_block_log_tail(tp, bp);
 800         /*
 801          * Remove the leaf entry by marking it stale.
 802          */
 803         blp[ent].address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 804         xfs_dir2_block_log_leaf(tp, bp, ent, ent);
 805         /*
 806          * Fix up bestfree, log the header if necessary.
 807          */
 808         if (needscan)
 809                 xfs_dir2_data_freescan(dp, hdr, &needlog);
 810         if (needlog)
 811                 xfs_dir2_data_log_header(args, bp);
 812         xfs_dir3_data_check(dp, bp);
 813         /*
 814          * See if the size as a shortform is good enough.
 815          */
 816         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
 817         if (size > XFS_IFORK_DSIZE(dp))
 818                 return 0;
 819 
 820         /*
 821          * If it works, do the conversion.
 822          */
 823         return xfs_dir2_block_to_sf(args, bp, size, &sfh);
 824 }
 825 
 826 /*
 827  * Replace an entry in a V2 block directory.
 828  * Change the inode number to the new value.
 829  */
 830 int                                             /* error */
 831 xfs_dir2_block_replace(
 832         xfs_da_args_t           *args)          /* directory operation args */
 833 {
 834         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 835         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
 836         struct xfs_buf          *bp;            /* block buffer */
 837         xfs_dir2_block_tail_t   *btp;           /* block tail */
 838         xfs_dir2_data_entry_t   *dep;           /* block data entry */
 839         xfs_inode_t             *dp;            /* incore inode */
 840         int                     ent;            /* leaf entry index */
 841         int                     error;          /* error return value */
 842 
 843         trace_xfs_dir2_block_replace(args);
 844 
 845         /*
 846          * Lookup the entry in the directory.  Get buffer and entry index.
 847          * This will always succeed since the caller has already done a lookup.
 848          */
 849         if ((error = xfs_dir2_block_lookup_int(args, &bp, &ent))) {
 850                 return error;
 851         }
 852         dp = args->dp;
 853         hdr = bp->b_addr;
 854         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 855         blp = xfs_dir2_block_leaf_p(btp);
 856         /*
 857          * Point to the data entry we need to change.
 858          */
 859         dep = (xfs_dir2_data_entry_t *)((char *)hdr +
 860                         xfs_dir2_dataptr_to_off(args->geo,
 861                                                 be32_to_cpu(blp[ent].address)));
 862         ASSERT(be64_to_cpu(dep->inumber) != args->inumber);
 863         /*
 864          * Change the inode number to the new value.
 865          */
 866         dep->inumber = cpu_to_be64(args->inumber);
 867         dp->d_ops->data_put_ftype(dep, args->filetype);
 868         xfs_dir2_data_log_entry(args, bp, dep);
 869         xfs_dir3_data_check(dp, bp);
 870         return 0;
 871 }
 872 
 873 /*
 874  * Qsort comparison routine for the block leaf entries.
 875  */
 876 static int                                      /* sort order */
 877 xfs_dir2_block_sort(
 878         const void                      *a,     /* first leaf entry */
 879         const void                      *b)     /* second leaf entry */
 880 {
 881         const xfs_dir2_leaf_entry_t     *la;    /* first leaf entry */
 882         const xfs_dir2_leaf_entry_t     *lb;    /* second leaf entry */
 883 
 884         la = a;
 885         lb = b;
 886         return be32_to_cpu(la->hashval) < be32_to_cpu(lb->hashval) ? -1 :
 887                 (be32_to_cpu(la->hashval) > be32_to_cpu(lb->hashval) ? 1 : 0);
 888 }
 889 
 890 /*
 891  * Convert a V2 leaf directory to a V2 block directory if possible.
 892  */
 893 int                                             /* error */
 894 xfs_dir2_leaf_to_block(
 895         xfs_da_args_t           *args,          /* operation arguments */
 896         struct xfs_buf          *lbp,           /* leaf buffer */
 897         struct xfs_buf          *dbp)           /* data buffer */
 898 {
 899         __be16                  *bestsp;        /* leaf bests table */
 900         xfs_dir2_data_hdr_t     *hdr;           /* block header */
 901         xfs_dir2_block_tail_t   *btp;           /* block tail */
 902         xfs_inode_t             *dp;            /* incore directory inode */
 903         xfs_dir2_data_unused_t  *dup;           /* unused data entry */
 904         int                     error;          /* error return value */
 905         int                     from;           /* leaf from index */
 906         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 907         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 908         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 909         xfs_mount_t             *mp;            /* file system mount point */
 910         int                     needlog;        /* need to log data header */
 911         int                     needscan;       /* need to scan for bestfree */
 912         xfs_dir2_sf_hdr_t       sfh;            /* shortform header */
 913         int                     size;           /* bytes used */
 914         __be16                  *tagp;          /* end of entry (tag) */
 915         int                     to;             /* block/leaf to index */
 916         xfs_trans_t             *tp;            /* transaction pointer */
 917         struct xfs_dir2_leaf_entry *ents;
 918         struct xfs_dir3_icleaf_hdr leafhdr;
 919 
 920         trace_xfs_dir2_leaf_to_block(args);
 921 
 922         dp = args->dp;
 923         tp = args->trans;
 924         mp = dp->i_mount;
 925         leaf = lbp->b_addr;
 926         dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 927         ents = dp->d_ops->leaf_ents_p(leaf);
 928         ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 929 
 930         ASSERT(leafhdr.magic == XFS_DIR2_LEAF1_MAGIC ||
 931                leafhdr.magic == XFS_DIR3_LEAF1_MAGIC);
 932         /*
 933          * If there are data blocks other than the first one, take this
 934          * opportunity to remove trailing empty data blocks that may have
 935          * been left behind during no-space-reservation operations.
 936          * These will show up in the leaf bests table.
 937          */
 938         while (dp->i_d.di_size > args->geo->blksize) {
 939                 int hdrsz;
 940 
 941                 hdrsz = dp->d_ops->data_entry_offset;
 942                 bestsp = xfs_dir2_leaf_bests_p(ltp);
 943                 if (be16_to_cpu(bestsp[be32_to_cpu(ltp->bestcount) - 1]) ==
 944                                             args->geo->blksize - hdrsz) {
 945                         if ((error =
 946                             xfs_dir2_leaf_trim_data(args, lbp,
 947                                     (xfs_dir2_db_t)(be32_to_cpu(ltp->bestcount) - 1))))
 948                                 return error;
 949                 } else
 950                         return 0;
 951         }
 952         /*
 953          * Read the data block if we don't already have it, give up if it fails.
 954          */
 955         if (!dbp) {
 956                 error = xfs_dir3_data_read(tp, dp, args->geo->datablk, -1, &dbp);
 957                 if (error)
 958                         return error;
 959         }
 960         hdr = dbp->b_addr;
 961         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
 962                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
 963 
 964         /*
 965          * Size of the "leaf" area in the block.
 966          */
 967         size = (uint)sizeof(xfs_dir2_block_tail_t) +
 968                (uint)sizeof(*lep) * (leafhdr.count - leafhdr.stale);
 969         /*
 970          * Look at the last data entry.
 971          */
 972         tagp = (__be16 *)((char *)hdr + args->geo->blksize) - 1;
 973         dup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
 974         /*
 975          * If it's not free or is too short we can't do it.
 976          */
 977         if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG ||
 978             be16_to_cpu(dup->length) < size)
 979                 return 0;
 980 
 981         /*
 982          * Start converting it to block form.
 983          */
 984         xfs_dir3_block_init(mp, tp, dbp, dp);
 985 
 986         needlog = 1;
 987         needscan = 0;
 988         /*
 989          * Use up the space at the end of the block (blp/btp).
 990          */
 991         error = xfs_dir2_data_use_free(args, dbp, dup,
 992                         args->geo->blksize - size, size, &needlog, &needscan);
 993         if (error)
 994                 return error;
 995         /*
 996          * Initialize the block tail.
 997          */
 998         btp = xfs_dir2_block_tail_p(args->geo, hdr);
 999         btp->count = cpu_to_be32(leafhdr.count - leafhdr.stale);
1000         btp->stale = 0;
1001         xfs_dir2_block_log_tail(tp, dbp);
1002         /*
1003          * Initialize the block leaf area.  We compact out stale entries.
1004          */
1005         lep = xfs_dir2_block_leaf_p(btp);
1006         for (from = to = 0; from < leafhdr.count; from++) {
1007                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
1008                         continue;
1009                 lep[to++] = ents[from];
1010         }
1011         ASSERT(to == be32_to_cpu(btp->count));
1012         xfs_dir2_block_log_leaf(tp, dbp, 0, be32_to_cpu(btp->count) - 1);
1013         /*
1014          * Scan the bestfree if we need it and log the data block header.
1015          */
1016         if (needscan)
1017                 xfs_dir2_data_freescan(dp, hdr, &needlog);
1018         if (needlog)
1019                 xfs_dir2_data_log_header(args, dbp);
1020         /*
1021          * Pitch the old leaf block.
1022          */
1023         error = xfs_da_shrink_inode(args, args->geo->leafblk, lbp);
1024         if (error)
1025                 return error;
1026 
1027         /*
1028          * Now see if the resulting block can be shrunken to shortform.
1029          */
1030         size = xfs_dir2_block_sfsize(dp, hdr, &sfh);
1031         if (size > XFS_IFORK_DSIZE(dp))
1032                 return 0;
1033 
1034         return xfs_dir2_block_to_sf(args, dbp, size, &sfh);
1035 }
1036 
1037 /*
1038  * Convert the shortform directory to block form.
1039  */
1040 int                                             /* error */
1041 xfs_dir2_sf_to_block(
1042         xfs_da_args_t           *args)          /* operation arguments */
1043 {
1044         xfs_dir2_db_t           blkno;          /* dir-relative block # (0) */
1045         xfs_dir2_data_hdr_t     *hdr;           /* block header */
1046         xfs_dir2_leaf_entry_t   *blp;           /* block leaf entries */
1047         struct xfs_buf          *bp;            /* block buffer */
1048         xfs_dir2_block_tail_t   *btp;           /* block tail pointer */
1049         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1050         xfs_inode_t             *dp;            /* incore directory inode */
1051         int                     dummy;          /* trash */
1052         xfs_dir2_data_unused_t  *dup;           /* unused entry pointer */
1053         int                     endoffset;      /* end of data objects */
1054         int                     error;          /* error return value */
1055         int                     i;              /* index */
1056         xfs_mount_t             *mp;            /* filesystem mount point */
1057         int                     needlog;        /* need to log block header */
1058         int                     needscan;       /* need to scan block freespc */
1059         int                     newoffset;      /* offset from current entry */
1060         int                     offset;         /* target block offset */
1061         xfs_dir2_sf_entry_t     *sfep;          /* sf entry pointer */
1062         xfs_dir2_sf_hdr_t       *oldsfp;        /* old shortform header  */
1063         xfs_dir2_sf_hdr_t       *sfp;           /* shortform header  */
1064         __be16                  *tagp;          /* end of data entry */
1065         xfs_trans_t             *tp;            /* transaction pointer */
1066         struct xfs_name         name;
1067         struct xfs_ifork        *ifp;
1068 
1069         trace_xfs_dir2_sf_to_block(args);
1070 
1071         dp = args->dp;
1072         tp = args->trans;
1073         mp = dp->i_mount;
1074         ifp = XFS_IFORK_PTR(dp, XFS_DATA_FORK);
1075         ASSERT(ifp->if_flags & XFS_IFINLINE);
1076         /*
1077          * Bomb out if the shortform directory is way too short.
1078          */
1079         if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
1080                 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1081                 return -EIO;
1082         }
1083 
1084         oldsfp = (xfs_dir2_sf_hdr_t *)ifp->if_u1.if_data;
1085 
1086         ASSERT(ifp->if_bytes == dp->i_d.di_size);
1087         ASSERT(ifp->if_u1.if_data != NULL);
1088         ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(oldsfp->i8count));
1089         ASSERT(dp->i_d.di_nextents == 0);
1090 
1091         /*
1092          * Copy the directory into a temporary buffer.
1093          * Then pitch the incore inode data so we can make extents.
1094          */
1095         sfp = kmem_alloc(ifp->if_bytes, 0);
1096         memcpy(sfp, oldsfp, ifp->if_bytes);
1097 
1098         xfs_idata_realloc(dp, -ifp->if_bytes, XFS_DATA_FORK);
1099         xfs_bmap_local_to_extents_empty(tp, dp, XFS_DATA_FORK);
1100         dp->i_d.di_size = 0;
1101 
1102         /*
1103          * Add block 0 to the inode.
1104          */
1105         error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE, &blkno);
1106         if (error)
1107                 goto out_free;
1108         /*
1109          * Initialize the data block, then convert it to block format.
1110          */
1111         error = xfs_dir3_data_init(args, blkno, &bp);
1112         if (error)
1113                 goto out_free;
1114         xfs_dir3_block_init(mp, tp, bp, dp);
1115         hdr = bp->b_addr;
1116 
1117         /*
1118          * Compute size of block "tail" area.
1119          */
1120         i = (uint)sizeof(*btp) +
1121             (sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t);
1122         /*
1123          * The whole thing is initialized to free by the init routine.
1124          * Say we're using the leaf and tail area.
1125          */
1126         dup = dp->d_ops->data_unused_p(hdr);
1127         needlog = needscan = 0;
1128         error = xfs_dir2_data_use_free(args, bp, dup, args->geo->blksize - i,
1129                         i, &needlog, &needscan);
1130         if (error)
1131                 goto out_free;
1132         ASSERT(needscan == 0);
1133         /*
1134          * Fill in the tail.
1135          */
1136         btp = xfs_dir2_block_tail_p(args->geo, hdr);
1137         btp->count = cpu_to_be32(sfp->count + 2);       /* ., .. */
1138         btp->stale = 0;
1139         blp = xfs_dir2_block_leaf_p(btp);
1140         endoffset = (uint)((char *)blp - (char *)hdr);
1141         /*
1142          * Remove the freespace, we'll manage it.
1143          */
1144         error = xfs_dir2_data_use_free(args, bp, dup,
1145                         (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr),
1146                         be16_to_cpu(dup->length), &needlog, &needscan);
1147         if (error)
1148                 goto out_free;
1149         /*
1150          * Create entry for .
1151          */
1152         dep = dp->d_ops->data_dot_entry_p(hdr);
1153         dep->inumber = cpu_to_be64(dp->i_ino);
1154         dep->namelen = 1;
1155         dep->name[0] = '.';
1156         dp->d_ops->data_put_ftype(dep, XFS_DIR3_FT_DIR);
1157         tagp = dp->d_ops->data_entry_tag_p(dep);
1158         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1159         xfs_dir2_data_log_entry(args, bp, dep);
1160         blp[0].hashval = cpu_to_be32(xfs_dir_hash_dot);
1161         blp[0].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(
1162                                 (char *)dep - (char *)hdr));
1163         /*
1164          * Create entry for ..
1165          */
1166         dep = dp->d_ops->data_dotdot_entry_p(hdr);
1167         dep->inumber = cpu_to_be64(dp->d_ops->sf_get_parent_ino(sfp));
1168         dep->namelen = 2;
1169         dep->name[0] = dep->name[1] = '.';
1170         dp->d_ops->data_put_ftype(dep, XFS_DIR3_FT_DIR);
1171         tagp = dp->d_ops->data_entry_tag_p(dep);
1172         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1173         xfs_dir2_data_log_entry(args, bp, dep);
1174         blp[1].hashval = cpu_to_be32(xfs_dir_hash_dotdot);
1175         blp[1].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(
1176                                 (char *)dep - (char *)hdr));
1177         offset = dp->d_ops->data_first_offset;
1178         /*
1179          * Loop over existing entries, stuff them in.
1180          */
1181         i = 0;
1182         if (!sfp->count)
1183                 sfep = NULL;
1184         else
1185                 sfep = xfs_dir2_sf_firstentry(sfp);
1186         /*
1187          * Need to preserve the existing offset values in the sf directory.
1188          * Insert holes (unused entries) where necessary.
1189          */
1190         while (offset < endoffset) {
1191                 /*
1192                  * sfep is null when we reach the end of the list.
1193                  */
1194                 if (sfep == NULL)
1195                         newoffset = endoffset;
1196                 else
1197                         newoffset = xfs_dir2_sf_get_offset(sfep);
1198                 /*
1199                  * There should be a hole here, make one.
1200                  */
1201                 if (offset < newoffset) {
1202                         dup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
1203                         dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1204                         dup->length = cpu_to_be16(newoffset - offset);
1205                         *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16(
1206                                 ((char *)dup - (char *)hdr));
1207                         xfs_dir2_data_log_unused(args, bp, dup);
1208                         xfs_dir2_data_freeinsert(hdr,
1209                                                  dp->d_ops->data_bestfree_p(hdr),
1210                                                  dup, &dummy);
1211                         offset += be16_to_cpu(dup->length);
1212                         continue;
1213                 }
1214                 /*
1215                  * Copy a real entry.
1216                  */
1217                 dep = (xfs_dir2_data_entry_t *)((char *)hdr + newoffset);
1218                 dep->inumber = cpu_to_be64(dp->d_ops->sf_get_ino(sfp, sfep));
1219                 dep->namelen = sfep->namelen;
1220                 dp->d_ops->data_put_ftype(dep, dp->d_ops->sf_get_ftype(sfep));
1221                 memcpy(dep->name, sfep->name, dep->namelen);
1222                 tagp = dp->d_ops->data_entry_tag_p(dep);
1223                 *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1224                 xfs_dir2_data_log_entry(args, bp, dep);
1225                 name.name = sfep->name;
1226                 name.len = sfep->namelen;
1227                 blp[2 + i].hashval = cpu_to_be32(mp->m_dirnameops->
1228                                                         hashname(&name));
1229                 blp[2 + i].address = cpu_to_be32(xfs_dir2_byte_to_dataptr(
1230                                                  (char *)dep - (char *)hdr));
1231                 offset = (int)((char *)(tagp + 1) - (char *)hdr);
1232                 if (++i == sfp->count)
1233                         sfep = NULL;
1234                 else
1235                         sfep = dp->d_ops->sf_nextentry(sfp, sfep);
1236         }
1237         /* Done with the temporary buffer */
1238         kmem_free(sfp);
1239         /*
1240          * Sort the leaf entries by hash value.
1241          */
1242         xfs_sort(blp, be32_to_cpu(btp->count), sizeof(*blp), xfs_dir2_block_sort);
1243         /*
1244          * Log the leaf entry area and tail.
1245          * Already logged the header in data_init, ignore needlog.
1246          */
1247         ASSERT(needscan == 0);
1248         xfs_dir2_block_log_leaf(tp, bp, 0, be32_to_cpu(btp->count) - 1);
1249         xfs_dir2_block_log_tail(tp, bp);
1250         xfs_dir3_data_check(dp, bp);
1251         return 0;
1252 out_free:
1253         kmem_free(sfp);
1254         return error;
1255 }