git.oblomov.eu Git - linux-2.6/blob - fs/xfs/xfs_dir2_node.c

   1 /*
   2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_types.h"
  21 #include "xfs_log.h"
  22 #include "xfs_inum.h"
  23 #include "xfs_trans.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_dir.h"
  26 #include "xfs_dir2.h"
  27 #include "xfs_dmapi.h"
  28 #include "xfs_mount.h"
  29 #include "xfs_da_btree.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_dir_sf.h"
  32 #include "xfs_dir2_sf.h"
  33 #include "xfs_attr_sf.h"
  34 #include "xfs_dinode.h"
  35 #include "xfs_inode.h"
  36 #include "xfs_bmap.h"
  37 #include "xfs_dir2_data.h"
  38 #include "xfs_dir2_leaf.h"
  39 #include "xfs_dir2_block.h"
  40 #include "xfs_dir2_node.h"
  41 #include "xfs_dir2_trace.h"
  42 #include "xfs_error.h"
  43
  44 /*
  45  * Function declarations.
  46  */
  47 static void xfs_dir2_free_log_header(xfs_trans_t *tp, xfs_dabuf_t *bp);
  48 static int xfs_dir2_leafn_add(xfs_dabuf_t *bp, xfs_da_args_t *args, int index);
  49 #ifdef DEBUG
  50 static void xfs_dir2_leafn_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
  51 #else
  52 #define xfs_dir2_leafn_check(dp, bp)
  53 #endif
  54 static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, xfs_dabuf_t *bp_s,
  55                                     int start_s, xfs_dabuf_t *bp_d, int start_d,
  56                                     int count);
  57 static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  58                                      xfs_da_state_blk_t *blk1,
  59                                      xfs_da_state_blk_t *blk2);
  60 static int xfs_dir2_leafn_remove(xfs_da_args_t *args, xfs_dabuf_t *bp,
  61                                  int index, xfs_da_state_blk_t *dblk,
  62                                  int *rval);
  63 static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  64                                      xfs_da_state_blk_t *fblk);
  65
  66 /*
  67  * Log entries from a freespace block.
  68  */
  69 void
  70 xfs_dir2_free_log_bests(
  71         xfs_trans_t             *tp,            /* transaction pointer */
  72         xfs_dabuf_t             *bp,            /* freespace buffer */
  73         int                     first,          /* first entry to log */
  74         int                     last)           /* last entry to log */
  75 {
  76         xfs_dir2_free_t         *free;          /* freespace structure */
  77
  78         free = bp->data;
  79         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
  80         xfs_da_log_buf(tp, bp,
  81                 (uint)((char *)&free->bests[first] - (char *)free),
  82                 (uint)((char *)&free->bests[last] - (char *)free +
  83                        sizeof(free->bests[0]) - 1));
  84 }
  85
  86 /*
  87  * Log header from a freespace block.
  88  */
  89 static void
  90 xfs_dir2_free_log_header(
  91         xfs_trans_t             *tp,            /* transaction pointer */
  92         xfs_dabuf_t             *bp)            /* freespace buffer */
  93 {
  94         xfs_dir2_free_t         *free;          /* freespace structure */
  95
  96         free = bp->data;
  97         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
  98         xfs_da_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
  99                 (uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
 100 }
 101
 102 /*
 103  * Convert a leaf-format directory to a node-format directory.
 104  * We need to change the magic number of the leaf block, and copy
 105  * the freespace table out of the leaf block into its own block.
 106  */
 107 int                                             /* error */
 108 xfs_dir2_leaf_to_node(
 109         xfs_da_args_t           *args,          /* operation arguments */
 110         xfs_dabuf_t             *lbp)           /* leaf buffer */
 111 {
 112         xfs_inode_t             *dp;            /* incore directory inode */
 113         int                     error;          /* error return value */
 114         xfs_dabuf_t             *fbp;           /* freespace buffer */
 115         xfs_dir2_db_t           fdb;            /* freespace block number */
 116         xfs_dir2_free_t         *free;          /* freespace structure */
 117         xfs_dir2_data_off_t     *from;          /* pointer to freespace entry */
 118         int                     i;              /* leaf freespace index */
 119         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 120         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 121         xfs_mount_t             *mp;            /* filesystem mount point */
 122         int                     n;              /* count of live freespc ents */
 123         xfs_dir2_data_off_t     off;            /* freespace entry value */
 124         xfs_dir2_data_off_t     *to;            /* pointer to freespace entry */
 125         xfs_trans_t             *tp;            /* transaction pointer */
 126
 127         xfs_dir2_trace_args_b("leaf_to_node", args, lbp);
 128         dp = args->dp;
 129         mp = dp->i_mount;
 130         tp = args->trans;
 131         /*
 132          * Add a freespace block to the directory.
 133          */
 134         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 135                 return error;
 136         }
 137         ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 138         /*
 139          * Get the buffer for the new freespace block.
 140          */
 141         if ((error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb), -1, &fbp,
 142                         XFS_DATA_FORK))) {
 143                 return error;
 144         }
 145         ASSERT(fbp != NULL);
 146         free = fbp->data;
 147         leaf = lbp->data;
 148         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
 149         /*
 150          * Initialize the freespace block header.
 151          */
 152         INT_SET(free->hdr.magic, ARCH_CONVERT, XFS_DIR2_FREE_MAGIC);
 153         free->hdr.firstdb = 0;
 154         ASSERT(INT_GET(ltp->bestcount, ARCH_CONVERT) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
 155         INT_COPY(free->hdr.nvalid, ltp->bestcount, ARCH_CONVERT);
 156         /*
 157          * Copy freespace entries from the leaf block to the new block.
 158          * Count active entries.
 159          */
 160         for (i = n = 0, from = XFS_DIR2_LEAF_BESTS_P(ltp), to = free->bests;
 161              i < INT_GET(ltp->bestcount, ARCH_CONVERT); i++, from++, to++) {
 162                 if ((off = INT_GET(*from, ARCH_CONVERT)) != NULLDATAOFF)
 163                         n++;
 164                 INT_SET(*to, ARCH_CONVERT, off);
 165         }
 166         INT_SET(free->hdr.nused, ARCH_CONVERT, n);
 167         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, XFS_DIR2_LEAFN_MAGIC);
 168         /*
 169          * Log everything.
 170          */
 171         xfs_dir2_leaf_log_header(tp, lbp);
 172         xfs_dir2_free_log_header(tp, fbp);
 173         xfs_dir2_free_log_bests(tp, fbp, 0, INT_GET(free->hdr.nvalid, ARCH_CONVERT) - 1);
 174         xfs_da_buf_done(fbp);
 175         xfs_dir2_leafn_check(dp, lbp);
 176         return 0;
 177 }
 178
 179 /*
 180  * Add a leaf entry to a leaf block in a node-form directory.
 181  * The other work necessary is done from the caller.
 182  */
 183 static int                                      /* error */
 184 xfs_dir2_leafn_add(
 185         xfs_dabuf_t             *bp,            /* leaf buffer */
 186         xfs_da_args_t           *args,          /* operation arguments */
 187         int                     index)          /* insertion pt for new entry */
 188 {
 189         int                     compact;        /* compacting stale leaves */
 190         xfs_inode_t             *dp;            /* incore directory inode */
 191         int                     highstale;      /* next stale entry */
 192         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 193         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 194         int                     lfloghigh;      /* high leaf entry logging */
 195         int                     lfloglow;       /* low leaf entry logging */
 196         int                     lowstale;       /* previous stale entry */
 197         xfs_mount_t             *mp;            /* filesystem mount point */
 198         xfs_trans_t             *tp;            /* transaction pointer */
 199
 200         xfs_dir2_trace_args_sb("leafn_add", args, index, bp);
 201         dp = args->dp;
 202         mp = dp->i_mount;
 203         tp = args->trans;
 204         leaf = bp->data;
 205
 206         /*
 207          * Quick check just to make sure we are not going to index
 208          * into other peoples memory
 209          */
 210         if (index < 0)
 211                 return XFS_ERROR(EFSCORRUPTED);
 212
 213         /*
 214          * If there are already the maximum number of leaf entries in
 215          * the block, if there are no stale entries it won't fit.
 216          * Caller will do a split.  If there are stale entries we'll do
 217          * a compact.
 218          */
 219
 220         if (INT_GET(leaf->hdr.count, ARCH_CONVERT) == XFS_DIR2_MAX_LEAF_ENTS(mp)) {
 221                 if (!leaf->hdr.stale)
 222                         return XFS_ERROR(ENOSPC);
 223                 compact = INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1;
 224         } else
 225                 compact = 0;
 226         ASSERT(index == 0 || INT_GET(leaf->ents[index - 1].hashval, ARCH_CONVERT) <= args->hashval);
 227         ASSERT(index == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 228                INT_GET(leaf->ents[index].hashval, ARCH_CONVERT) >= args->hashval);
 229
 230         if (args->justcheck)
 231                 return 0;
 232
 233         /*
 234          * Compact out all but one stale leaf entry.  Leaves behind
 235          * the entry closest to index.
 236          */
 237         if (compact) {
 238                 xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
 239                         &lfloglow, &lfloghigh);
 240         }
 241         /*
 242          * Set impossible logging indices for this case.
 243          */
 244         else if (leaf->hdr.stale) {
 245                 lfloglow = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 246                 lfloghigh = -1;
 247         }
 248         /*
 249          * No stale entries, just insert a space for the new entry.
 250          */
 251         if (!leaf->hdr.stale) {
 252                 lep = &leaf->ents[index];
 253                 if (index < INT_GET(leaf->hdr.count, ARCH_CONVERT))
 254                         memmove(lep + 1, lep,
 255                                 (INT_GET(leaf->hdr.count, ARCH_CONVERT) - index) * sizeof(*lep));
 256                 lfloglow = index;
 257                 lfloghigh = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 258                 INT_MOD(leaf->hdr.count, ARCH_CONVERT, +1);
 259         }
 260         /*
 261          * There are stale entries.  We'll use one for the new entry.
 262          */
 263         else {
 264                 /*
 265                  * If we didn't do a compact then we need to figure out
 266                  * which stale entry will be used.
 267                  */
 268                 if (compact == 0) {
 269                         /*
 270                          * Find first stale entry before our insertion point.
 271                          */
 272                         for (lowstale = index - 1;
 273                              lowstale >= 0 &&
 274                                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) !=
 275                                 XFS_DIR2_NULL_DATAPTR;
 276                              lowstale--)
 277                                 continue;
 278                         /*
 279                          * Find next stale entry after insertion point.
 280                          * Stop looking if the answer would be worse than
 281                          * lowstale already found.
 282                          */
 283                         for (highstale = index;
 284                              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
 285                                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) !=
 286                                 XFS_DIR2_NULL_DATAPTR &&
 287                                 (lowstale < 0 ||
 288                                  index - lowstale - 1 >= highstale - index);
 289                              highstale++)
 290                                 continue;
 291                 }
 292                 /*
 293                  * Using the low stale entry.
 294                  * Shift entries up toward the stale slot.
 295                  */
 296                 if (lowstale >= 0 &&
 297                     (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 298                      index - lowstale - 1 < highstale - index)) {
 299                         ASSERT(INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) ==
 300                                XFS_DIR2_NULL_DATAPTR);
 301                         ASSERT(index - lowstale - 1 >= 0);
 302                         if (index - lowstale - 1 > 0)
 303                                 memmove(&leaf->ents[lowstale],
 304                                         &leaf->ents[lowstale + 1],
 305                                         (index - lowstale - 1) * sizeof(*lep));
 306                         lep = &leaf->ents[index - 1];
 307                         lfloglow = MIN(lowstale, lfloglow);
 308                         lfloghigh = MAX(index - 1, lfloghigh);
 309                 }
 310                 /*
 311                  * Using the high stale entry.
 312                  * Shift entries down toward the stale slot.
 313                  */
 314                 else {
 315                         ASSERT(INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) ==
 316                                XFS_DIR2_NULL_DATAPTR);
 317                         ASSERT(highstale - index >= 0);
 318                         if (highstale - index > 0)
 319                                 memmove(&leaf->ents[index + 1],
 320                                         &leaf->ents[index],
 321                                         (highstale - index) * sizeof(*lep));
 322                         lep = &leaf->ents[index];
 323                         lfloglow = MIN(index, lfloglow);
 324                         lfloghigh = MAX(highstale, lfloghigh);
 325                 }
 326                 INT_MOD(leaf->hdr.stale, ARCH_CONVERT, -1);
 327         }
 328         /*
 329          * Insert the new entry, log everything.
 330          */
 331         INT_SET(lep->hashval, ARCH_CONVERT, args->hashval);
 332         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_DB_OFF_TO_DATAPTR(mp, args->blkno, args->index));
 333         xfs_dir2_leaf_log_header(tp, bp);
 334         xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 335         xfs_dir2_leafn_check(dp, bp);
 336         return 0;
 337 }
 338
 339 #ifdef DEBUG
 340 /*
 341  * Check internal consistency of a leafn block.
 342  */
 343 void
 344 xfs_dir2_leafn_check(
 345         xfs_inode_t     *dp,                    /* incore directory inode */
 346         xfs_dabuf_t     *bp)                    /* leaf buffer */
 347 {
 348         int             i;                      /* leaf index */
 349         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 350         xfs_mount_t     *mp;                    /* filesystem mount point */
 351         int             stale;                  /* count of stale leaves */
 352
 353         leaf = bp->data;
 354         mp = dp->i_mount;
 355         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 356         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) <= XFS_DIR2_MAX_LEAF_ENTS(mp));
 357         for (i = stale = 0; i < INT_GET(leaf->hdr.count, ARCH_CONVERT); i++) {
 358                 if (i + 1 < INT_GET(leaf->hdr.count, ARCH_CONVERT)) {
 359                         ASSERT(INT_GET(leaf->ents[i].hashval, ARCH_CONVERT) <=
 360                                INT_GET(leaf->ents[i + 1].hashval, ARCH_CONVERT));
 361                 }
 362                 if (INT_GET(leaf->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 363                         stale++;
 364         }
 365         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == stale);
 366 }
 367 #endif  /* DEBUG */
 368
 369 /*
 370  * Return the last hash value in the leaf.
 371  * Stale entries are ok.
 372  */
 373 xfs_dahash_t                                    /* hash value */
 374 xfs_dir2_leafn_lasthash(
 375         xfs_dabuf_t     *bp,                    /* leaf buffer */
 376         int             *count)                 /* count of entries in leaf */
 377 {
 378         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 379
 380         leaf = bp->data;
 381         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 382         if (count)
 383                 *count = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 384         if (!leaf->hdr.count)
 385                 return 0;
 386         return INT_GET(leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
 387 }
 388
 389 /*
 390  * Look up a leaf entry in a node-format leaf block.
 391  * If this is an addname then the extrablk in state is a freespace block,
 392  * otherwise it's a data block.
 393  */
 394 int
 395 xfs_dir2_leafn_lookup_int(
 396         xfs_dabuf_t             *bp,            /* leaf buffer */
 397         xfs_da_args_t           *args,          /* operation arguments */
 398         int                     *indexp,        /* out: leaf entry index */
 399         xfs_da_state_t          *state)         /* state to fill in */
 400 {
 401         xfs_dabuf_t             *curbp;         /* current data/free buffer */
 402         xfs_dir2_db_t           curdb;          /* current data block number */
 403         xfs_dir2_db_t           curfdb;         /* current free block number */
 404         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 405         xfs_inode_t             *dp;            /* incore directory inode */
 406         int                     error;          /* error return value */
 407         int                     fi;             /* free entry index */
 408         xfs_dir2_free_t         *free=NULL;     /* free block structure */
 409         int                     index;          /* leaf entry index */
 410         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 411         int                     length=0;       /* length of new data entry */
 412         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 413         xfs_mount_t             *mp;            /* filesystem mount point */
 414         xfs_dir2_db_t           newdb;          /* new data block number */
 415         xfs_dir2_db_t           newfdb;         /* new free block number */
 416         xfs_trans_t             *tp;            /* transaction pointer */
 417
 418         dp = args->dp;
 419         tp = args->trans;
 420         mp = dp->i_mount;
 421         leaf = bp->data;
 422         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 423 #ifdef __KERNEL__
 424         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) > 0);
 425 #endif
 426         xfs_dir2_leafn_check(dp, bp);
 427         /*
 428          * Look up the hash value in the leaf entries.
 429          */
 430         index = xfs_dir2_leaf_search_hash(args, bp);
 431         /*
 432          * Do we have a buffer coming in?
 433          */
 434         if (state->extravalid)
 435                 curbp = state->extrablk.bp;
 436         else
 437                 curbp = NULL;
 438         /*
 439          * For addname, it's a free block buffer, get the block number.
 440          */
 441         if (args->addname) {
 442                 curfdb = curbp ? state->extrablk.blkno : -1;
 443                 curdb = -1;
 444                 length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
 445                 if ((free = (curbp ? curbp->data : NULL)))
 446                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 447         }
 448         /*
 449          * For others, it's a data block buffer, get the block number.
 450          */
 451         else {
 452                 curfdb = -1;
 453                 curdb = curbp ? state->extrablk.blkno : -1;
 454         }
 455         /*
 456          * Loop over leaf entries with the right hash value.
 457          */
 458         for (lep = &leaf->ents[index];
 459              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
 460              lep++, index++) {
 461                 /*
 462                  * Skip stale leaf entries.
 463                  */
 464                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 465                         continue;
 466                 /*
 467                  * Pull the data block number from the entry.
 468                  */
 469                 newdb = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
 470                 /*
 471                  * For addname, we're looking for a place to put the new entry.
 472                  * We want to use a data block with an entry of equal
 473                  * hash value to ours if there is one with room.
 474                  */
 475                 if (args->addname) {
 476                         /*
 477                          * If this block isn't the data block we already have
 478                          * in hand, take a look at it.
 479                          */
 480                         if (newdb != curdb) {
 481                                 curdb = newdb;
 482                                 /*
 483                                  * Convert the data block to the free block
 484                                  * holding its freespace information.
 485                                  */
 486                                 newfdb = XFS_DIR2_DB_TO_FDB(mp, newdb);
 487                                 /*
 488                                  * If it's not the one we have in hand,
 489                                  * read it in.
 490                                  */
 491                                 if (newfdb != curfdb) {
 492                                         /*
 493                                          * If we had one before, drop it.
 494                                          */
 495                                         if (curbp)
 496                                                 xfs_da_brelse(tp, curbp);
 497                                         /*
 498                                          * Read the free block.
 499                                          */
 500                                         if ((error = xfs_da_read_buf(tp, dp,
 501                                                         XFS_DIR2_DB_TO_DA(mp,
 502                                                                 newfdb),
 503                                                         -1, &curbp,
 504                                                         XFS_DATA_FORK))) {
 505                                                 return error;
 506                                         }
 507                                         curfdb = newfdb;
 508                                         free = curbp->data;
 509                                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) ==
 510                                                XFS_DIR2_FREE_MAGIC);
 511                                         ASSERT((INT_GET(free->hdr.firstdb, ARCH_CONVERT) %
 512                                                 XFS_DIR2_MAX_FREE_BESTS(mp)) ==
 513                                                0);
 514                                         ASSERT(INT_GET(free->hdr.firstdb, ARCH_CONVERT) <= curdb);
 515                                         ASSERT(curdb <
 516                                                INT_GET(free->hdr.firstdb, ARCH_CONVERT) +
 517                                                INT_GET(free->hdr.nvalid, ARCH_CONVERT));
 518                                 }
 519                                 /*
 520                                  * Get the index for our entry.
 521                                  */
 522                                 fi = XFS_DIR2_DB_TO_FDINDEX(mp, curdb);
 523                                 /*
 524                                  * If it has room, return it.
 525                                  */
 526                                 if (unlikely(INT_GET(free->bests[fi], ARCH_CONVERT) == NULLDATAOFF)) {
 527                                         XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 528                                                          XFS_ERRLEVEL_LOW, mp);
 529                                         return XFS_ERROR(EFSCORRUPTED);
 530                                 }
 531                                 if (INT_GET(free->bests[fi], ARCH_CONVERT) >= length) {
 532                                         *indexp = index;
 533                                         state->extravalid = 1;
 534                                         state->extrablk.bp = curbp;
 535                                         state->extrablk.blkno = curfdb;
 536                                         state->extrablk.index = fi;
 537                                         state->extrablk.magic =
 538                                                 XFS_DIR2_FREE_MAGIC;
 539                                         ASSERT(args->oknoent);
 540                                         return XFS_ERROR(ENOENT);
 541                                 }
 542                         }
 543                 }
 544                 /*
 545                  * Not adding a new entry, so we really want to find
 546                  * the name given to us.
 547                  */
 548                 else {
 549                         /*
 550                          * If it's a different data block, go get it.
 551                          */
 552                         if (newdb != curdb) {
 553                                 /*
 554                                  * If we had a block before, drop it.
 555                                  */
 556                                 if (curbp)
 557                                         xfs_da_brelse(tp, curbp);
 558                                 /*
 559                                  * Read the data block.
 560                                  */
 561                                 if ((error =
 562                                     xfs_da_read_buf(tp, dp,
 563                                             XFS_DIR2_DB_TO_DA(mp, newdb), -1,
 564                                             &curbp, XFS_DATA_FORK))) {
 565                                         return error;
 566                                 }
 567                                 xfs_dir2_data_check(dp, curbp);
 568                                 curdb = newdb;
 569                         }
 570                         /*
 571                          * Point to the data entry.
 572                          */
 573                         dep = (xfs_dir2_data_entry_t *)
 574                               ((char *)curbp->data +
 575                                XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
 576                         /*
 577                          * Compare the entry, return it if it matches.
 578                          */
 579                         if (dep->namelen == args->namelen &&
 580                             dep->name[0] == args->name[0] &&
 581                             memcmp(dep->name, args->name, args->namelen) == 0) {
 582                                 args->inumber = INT_GET(dep->inumber, ARCH_CONVERT);
 583                                 *indexp = index;
 584                                 state->extravalid = 1;
 585                                 state->extrablk.bp = curbp;
 586                                 state->extrablk.blkno = curdb;
 587                                 state->extrablk.index =
 588                                         (int)((char *)dep -
 589                                               (char *)curbp->data);
 590                                 state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 591                                 return XFS_ERROR(EEXIST);
 592                         }
 593                 }
 594         }
 595         /*
 596          * Didn't find a match.
 597          * If we are holding a buffer, give it back in case our caller
 598          * finds it useful.
 599          */
 600         if ((state->extravalid = (curbp != NULL))) {
 601                 state->extrablk.bp = curbp;
 602                 state->extrablk.index = -1;
 603                 /*
 604                  * For addname, giving back a free block.
 605                  */
 606                 if (args->addname) {
 607                         state->extrablk.blkno = curfdb;
 608                         state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 609                 }
 610                 /*
 611                  * For other callers, giving back a data block.
 612                  */
 613                 else {
 614                         state->extrablk.blkno = curdb;
 615                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 616                 }
 617         }
 618         /*
 619          * Return the final index, that will be the insertion point.
 620          */
 621         *indexp = index;
 622         ASSERT(index == INT_GET(leaf->hdr.count, ARCH_CONVERT) || args->oknoent);
 623         return XFS_ERROR(ENOENT);
 624 }
 625
 626 /*
 627  * Move count leaf entries from source to destination leaf.
 628  * Log entries and headers.  Stale entries are preserved.
 629  */
 630 static void
 631 xfs_dir2_leafn_moveents(
 632         xfs_da_args_t   *args,                  /* operation arguments */
 633         xfs_dabuf_t     *bp_s,                  /* source leaf buffer */
 634         int             start_s,                /* source leaf index */
 635         xfs_dabuf_t     *bp_d,                  /* destination leaf buffer */
 636         int             start_d,                /* destination leaf index */
 637         int             count)                  /* count of leaves to copy */
 638 {
 639         xfs_dir2_leaf_t *leaf_d;                /* destination leaf structure */
 640         xfs_dir2_leaf_t *leaf_s;                /* source leaf structure */
 641         int             stale;                  /* count stale leaves copied */
 642         xfs_trans_t     *tp;                    /* transaction pointer */
 643
 644         xfs_dir2_trace_args_bibii("leafn_moveents", args, bp_s, start_s, bp_d,
 645                 start_d, count);
 646         /*
 647          * Silently return if nothing to do.
 648          */
 649         if (count == 0) {
 650                 return;
 651         }
 652         tp = args->trans;
 653         leaf_s = bp_s->data;
 654         leaf_d = bp_d->data;
 655         /*
 656          * If the destination index is not the end of the current
 657          * destination leaf entries, open up a hole in the destination
 658          * to hold the new entries.
 659          */
 660         if (start_d < INT_GET(leaf_d->hdr.count, ARCH_CONVERT)) {
 661                 memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
 662                         (INT_GET(leaf_d->hdr.count, ARCH_CONVERT) - start_d) *
 663                         sizeof(xfs_dir2_leaf_entry_t));
 664                 xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
 665                         count + INT_GET(leaf_d->hdr.count, ARCH_CONVERT) - 1);
 666         }
 667         /*
 668          * If the source has stale leaves, count the ones in the copy range
 669          * so we can update the header correctly.
 670          */
 671         if (leaf_s->hdr.stale) {
 672                 int     i;                      /* temp leaf index */
 673
 674                 for (i = start_s, stale = 0; i < start_s + count; i++) {
 675                         if (INT_GET(leaf_s->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 676                                 stale++;
 677                 }
 678         } else
 679                 stale = 0;
 680         /*
 681          * Copy the leaf entries from source to destination.
 682          */
 683         memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
 684                 count * sizeof(xfs_dir2_leaf_entry_t));
 685         xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 686         /*
 687          * If there are source entries after the ones we copied,
 688          * delete the ones we copied by sliding the next ones down.
 689          */
 690         if (start_s + count < INT_GET(leaf_s->hdr.count, ARCH_CONVERT)) {
 691                 memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
 692                         count * sizeof(xfs_dir2_leaf_entry_t));
 693                 xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 694         }
 695         /*
 696          * Update the headers and log them.
 697          */
 698         INT_MOD(leaf_s->hdr.count, ARCH_CONVERT, -(count));
 699         INT_MOD(leaf_s->hdr.stale, ARCH_CONVERT, -(stale));
 700         INT_MOD(leaf_d->hdr.count, ARCH_CONVERT, count);
 701         INT_MOD(leaf_d->hdr.stale, ARCH_CONVERT, stale);
 702         xfs_dir2_leaf_log_header(tp, bp_s);
 703         xfs_dir2_leaf_log_header(tp, bp_d);
 704         xfs_dir2_leafn_check(args->dp, bp_s);
 705         xfs_dir2_leafn_check(args->dp, bp_d);
 706 }
 707
 708 /*
 709  * Determine the sort order of two leaf blocks.
 710  * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 711  */
 712 int                                             /* sort order */
 713 xfs_dir2_leafn_order(
 714         xfs_dabuf_t     *leaf1_bp,              /* leaf1 buffer */
 715         xfs_dabuf_t     *leaf2_bp)              /* leaf2 buffer */
 716 {
 717         xfs_dir2_leaf_t *leaf1;                 /* leaf1 structure */
 718         xfs_dir2_leaf_t *leaf2;                 /* leaf2 structure */
 719
 720         leaf1 = leaf1_bp->data;
 721         leaf2 = leaf2_bp->data;
 722         ASSERT(INT_GET(leaf1->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 723         ASSERT(INT_GET(leaf2->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 724         if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) > 0 &&
 725             INT_GET(leaf2->hdr.count, ARCH_CONVERT) > 0 &&
 726             (INT_GET(leaf2->ents[0].hashval, ARCH_CONVERT) < INT_GET(leaf1->ents[0].hashval, ARCH_CONVERT) ||
 727              INT_GET(leaf2->ents[INT_GET(leaf2->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT) <
 728              INT_GET(leaf1->ents[INT_GET(leaf1->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT)))
 729                 return 1;
 730         return 0;
 731 }
 732
 733 /*
 734  * Rebalance leaf entries between two leaf blocks.
 735  * This is actually only called when the second block is new,
 736  * though the code deals with the general case.
 737  * A new entry will be inserted in one of the blocks, and that
 738  * entry is taken into account when balancing.
 739  */
 740 static void
 741 xfs_dir2_leafn_rebalance(
 742         xfs_da_state_t          *state,         /* btree cursor */
 743         xfs_da_state_blk_t      *blk1,          /* first btree block */
 744         xfs_da_state_blk_t      *blk2)          /* second btree block */
 745 {
 746         xfs_da_args_t           *args;          /* operation arguments */
 747         int                     count;          /* count (& direction) leaves */
 748         int                     isleft;         /* new goes in left leaf */
 749         xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 750         xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
 751         int                     mid;            /* midpoint leaf index */
 752 #ifdef DEBUG
 753         int                     oldstale;       /* old count of stale leaves */
 754 #endif
 755         int                     oldsum;         /* old total leaf count */
 756         int                     swap;           /* swapped leaf blocks */
 757
 758         args = state->args;
 759         /*
 760          * If the block order is wrong, swap the arguments.
 761          */
 762         if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
 763                 xfs_da_state_blk_t      *tmp;   /* temp for block swap */
 764
 765                 tmp = blk1;
 766                 blk1 = blk2;
 767                 blk2 = tmp;
 768         }
 769         leaf1 = blk1->bp->data;
 770         leaf2 = blk2->bp->data;
 771         oldsum = INT_GET(leaf1->hdr.count, ARCH_CONVERT) + INT_GET(leaf2->hdr.count, ARCH_CONVERT);
 772 #ifdef DEBUG
 773         oldstale = INT_GET(leaf1->hdr.stale, ARCH_CONVERT) + INT_GET(leaf2->hdr.stale, ARCH_CONVERT);
 774 #endif
 775         mid = oldsum >> 1;
 776         /*
 777          * If the old leaf count was odd then the new one will be even,
 778          * so we need to divide the new count evenly.
 779          */
 780         if (oldsum & 1) {
 781                 xfs_dahash_t    midhash;        /* middle entry hash value */
 782
 783                 if (mid >= INT_GET(leaf1->hdr.count, ARCH_CONVERT))
 784                         midhash = INT_GET(leaf2->ents[mid - INT_GET(leaf1->hdr.count, ARCH_CONVERT)].hashval, ARCH_CONVERT);
 785                 else
 786                         midhash = INT_GET(leaf1->ents[mid].hashval, ARCH_CONVERT);
 787                 isleft = args->hashval <= midhash;
 788         }
 789         /*
 790          * If the old count is even then the new count is odd, so there's
 791          * no preferred side for the new entry.
 792          * Pick the left one.
 793          */
 794         else
 795                 isleft = 1;
 796         /*
 797          * Calculate moved entry count.  Positive means left-to-right,
 798          * negative means right-to-left.  Then move the entries.
 799          */
 800         count = INT_GET(leaf1->hdr.count, ARCH_CONVERT) - mid + (isleft == 0);
 801         if (count > 0)
 802                 xfs_dir2_leafn_moveents(args, blk1->bp,
 803                         INT_GET(leaf1->hdr.count, ARCH_CONVERT) - count, blk2->bp, 0, count);
 804         else if (count < 0)
 805                 xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
 806                         INT_GET(leaf1->hdr.count, ARCH_CONVERT), count);
 807         ASSERT(INT_GET(leaf1->hdr.count, ARCH_CONVERT) + INT_GET(leaf2->hdr.count, ARCH_CONVERT) == oldsum);
 808         ASSERT(INT_GET(leaf1->hdr.stale, ARCH_CONVERT) + INT_GET(leaf2->hdr.stale, ARCH_CONVERT) == oldstale);
 809         /*
 810          * Mark whether we're inserting into the old or new leaf.
 811          */
 812         if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) < INT_GET(leaf2->hdr.count, ARCH_CONVERT))
 813                 state->inleaf = swap;
 814         else if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) > INT_GET(leaf2->hdr.count, ARCH_CONVERT))
 815                 state->inleaf = !swap;
 816         else
 817                 state->inleaf =
 818                         swap ^ (blk1->index <= INT_GET(leaf1->hdr.count, ARCH_CONVERT));
 819         /*
 820          * Adjust the expected index for insertion.
 821          */
 822         if (!state->inleaf)
 823                 blk2->index = blk1->index - INT_GET(leaf1->hdr.count, ARCH_CONVERT);
 824
 825         /*
 826          * Finally sanity check just to make sure we are not returning a negative index
 827          */
 828         if(blk2->index < 0) {
 829                 state->inleaf = 1;
 830                 blk2->index = 0;
 831                 cmn_err(CE_ALERT,
 832                         "xfs_dir2_leafn_rebalance: picked the wrong leaf? reverting orignal leaf: "
 833                         "blk1->index %d\n",
 834                         blk1->index);
 835         }
 836 }
 837
 838 /*
 839  * Remove an entry from a node directory.
 840  * This removes the leaf entry and the data entry,
 841  * and updates the free block if necessary.
 842  */
 843 static int                                      /* error */
 844 xfs_dir2_leafn_remove(
 845         xfs_da_args_t           *args,          /* operation arguments */
 846         xfs_dabuf_t             *bp,            /* leaf buffer */
 847         int                     index,          /* leaf entry index */
 848         xfs_da_state_blk_t      *dblk,          /* data block */
 849         int                     *rval)          /* resulting block needs join */
 850 {
 851         xfs_dir2_data_t         *data;          /* data block structure */
 852         xfs_dir2_db_t           db;             /* data block number */
 853         xfs_dabuf_t             *dbp;           /* data block buffer */
 854         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 855         xfs_inode_t             *dp;            /* incore directory inode */
 856         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 857         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 858         int                     longest;        /* longest data free entry */
 859         int                     off;            /* data block entry offset */
 860         xfs_mount_t             *mp;            /* filesystem mount point */
 861         int                     needlog;        /* need to log data header */
 862         int                     needscan;       /* need to rescan data frees */
 863         xfs_trans_t             *tp;            /* transaction pointer */
 864
 865         xfs_dir2_trace_args_sb("leafn_remove", args, index, bp);
 866         dp = args->dp;
 867         tp = args->trans;
 868         mp = dp->i_mount;
 869         leaf = bp->data;
 870         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 871         /*
 872          * Point to the entry we're removing.
 873          */
 874         lep = &leaf->ents[index];
 875         /*
 876          * Extract the data block and offset from the entry.
 877          */
 878         db = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
 879         ASSERT(dblk->blkno == db);
 880         off = XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT));
 881         ASSERT(dblk->index == off);
 882         /*
 883          * Kill the leaf entry by marking it stale.
 884          * Log the leaf block changes.
 885          */
 886         INT_MOD(leaf->hdr.stale, ARCH_CONVERT, +1);
 887         xfs_dir2_leaf_log_header(tp, bp);
 888         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_NULL_DATAPTR);
 889         xfs_dir2_leaf_log_ents(tp, bp, index, index);
 890         /*
 891          * Make the data entry free.  Keep track of the longest freespace
 892          * in the data block in case it changes.
 893          */
 894         dbp = dblk->bp;
 895         data = dbp->data;
 896         dep = (xfs_dir2_data_entry_t *)((char *)data + off);
 897         longest = INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT);
 898         needlog = needscan = 0;
 899         xfs_dir2_data_make_free(tp, dbp, off,
 900                 XFS_DIR2_DATA_ENTSIZE(dep->namelen), &needlog, &needscan);
 901         /*
 902          * Rescan the data block freespaces for bestfree.
 903          * Log the data block header if needed.
 904          */
 905         if (needscan)
 906                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
 907         if (needlog)
 908                 xfs_dir2_data_log_header(tp, dbp);
 909         xfs_dir2_data_check(dp, dbp);
 910         /*
 911          * If the longest data block freespace changes, need to update
 912          * the corresponding freeblock entry.
 913          */
 914         if (longest < INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT)) {
 915                 int             error;          /* error return value */
 916                 xfs_dabuf_t     *fbp;           /* freeblock buffer */
 917                 xfs_dir2_db_t   fdb;            /* freeblock block number */
 918                 int             findex;         /* index in freeblock entries */
 919                 xfs_dir2_free_t *free;          /* freeblock structure */
 920                 int             logfree;        /* need to log free entry */
 921
 922                 /*
 923                  * Convert the data block number to a free block,
 924                  * read in the free block.
 925                  */
 926                 fdb = XFS_DIR2_DB_TO_FDB(mp, db);
 927                 if ((error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb),
 928                                 -1, &fbp, XFS_DATA_FORK))) {
 929                         return error;
 930                 }
 931                 free = fbp->data;
 932                 ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 933                 ASSERT(INT_GET(free->hdr.firstdb, ARCH_CONVERT) ==
 934                        XFS_DIR2_MAX_FREE_BESTS(mp) *
 935                        (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
 936                 /*
 937                  * Calculate which entry we need to fix.
 938                  */
 939                 findex = XFS_DIR2_DB_TO_FDINDEX(mp, db);
 940                 longest = INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT);
 941                 /*
 942                  * If the data block is now empty we can get rid of it
 943                  * (usually).
 944                  */
 945                 if (longest == mp->m_dirblksize - (uint)sizeof(data->hdr)) {
 946                         /*
 947                          * Try to punch out the data block.
 948                          */
 949                         error = xfs_dir2_shrink_inode(args, db, dbp);
 950                         if (error == 0) {
 951                                 dblk->bp = NULL;
 952                                 data = NULL;
 953                         }
 954                         /*
 955                          * We can get ENOSPC if there's no space reservation.
 956                          * In this case just drop the buffer and some one else
 957                          * will eventually get rid of the empty block.
 958                          */
 959                         else if (error == ENOSPC && args->total == 0)
 960                                 xfs_da_buf_done(dbp);
 961                         else
 962                                 return error;
 963                 }
 964                 /*
 965                  * If we got rid of the data block, we can eliminate that entry
 966                  * in the free block.
 967                  */
 968                 if (data == NULL) {
 969                         /*
 970                          * One less used entry in the free table.
 971                          */
 972                         INT_MOD(free->hdr.nused, ARCH_CONVERT, -1);
 973                         xfs_dir2_free_log_header(tp, fbp);
 974                         /*
 975                          * If this was the last entry in the table, we can
 976                          * trim the table size back.  There might be other
 977                          * entries at the end referring to non-existent
 978                          * data blocks, get those too.
 979                          */
 980                         if (findex == INT_GET(free->hdr.nvalid, ARCH_CONVERT) - 1) {
 981                                 int     i;              /* free entry index */
 982
 983                                 for (i = findex - 1;
 984                                      i >= 0 && INT_GET(free->bests[i], ARCH_CONVERT) == NULLDATAOFF;
 985                                      i--)
 986                                         continue;
 987                                 INT_SET(free->hdr.nvalid, ARCH_CONVERT, i + 1);
 988                                 logfree = 0;
 989                         }
 990                         /*
 991                          * Not the last entry, just punch it out.
 992                          */
 993                         else {
 994                                 INT_SET(free->bests[findex], ARCH_CONVERT, NULLDATAOFF);
 995                                 logfree = 1;
 996                         }
 997                         /*
 998                          * If there are no useful entries left in the block,
 999                          * get rid of the block if we can.
1000                          */
1001                         if (!free->hdr.nused) {
1002                                 error = xfs_dir2_shrink_inode(args, fdb, fbp);
1003                                 if (error == 0) {
1004                                         fbp = NULL;
1005                                         logfree = 0;
1006                                 } else if (error != ENOSPC || args->total != 0)
1007                                         return error;
1008                                 /*
1009                                  * It's possible to get ENOSPC if there is no
1010                                  * space reservation.  In this case some one
1011                                  * else will eventually get rid of this block.
1012                                  */
1013                         }
1014                 }
1015                 /*
1016                  * Data block is not empty, just set the free entry to
1017                  * the new value.
1018                  */
1019                 else {
1020                         INT_SET(free->bests[findex], ARCH_CONVERT, longest);
1021                         logfree = 1;
1022                 }
1023                 /*
1024                  * Log the free entry that changed, unless we got rid of it.
1025                  */
1026                 if (logfree)
1027                         xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1028                 /*
1029                  * Drop the buffer if we still have it.
1030                  */
1031                 if (fbp)
1032                         xfs_da_buf_done(fbp);
1033         }
1034         xfs_dir2_leafn_check(dp, bp);
1035         /*
1036          * Return indication of whether this leaf block is emtpy enough
1037          * to justify trying to join it with a neighbor.
1038          */
1039         *rval =
1040                 ((uint)sizeof(leaf->hdr) +
1041                  (uint)sizeof(leaf->ents[0]) *
1042                  (INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT))) <
1043                 mp->m_dir_magicpct;
1044         return 0;
1045 }
1046
1047 /*
1048  * Split the leaf entries in the old block into old and new blocks.
1049  */
1050 int                                             /* error */
1051 xfs_dir2_leafn_split(
1052         xfs_da_state_t          *state,         /* btree cursor */
1053         xfs_da_state_blk_t      *oldblk,        /* original block */
1054         xfs_da_state_blk_t      *newblk)        /* newly created block */
1055 {
1056         xfs_da_args_t           *args;          /* operation arguments */
1057         xfs_dablk_t             blkno;          /* new leaf block number */
1058         int                     error;          /* error return value */
1059         xfs_mount_t             *mp;            /* filesystem mount point */
1060
1061         /*
1062          * Allocate space for a new leaf node.
1063          */
1064         args = state->args;
1065         mp = args->dp->i_mount;
1066         ASSERT(args != NULL);
1067         ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1068         error = xfs_da_grow_inode(args, &blkno);
1069         if (error) {
1070                 return error;
1071         }
1072         /*
1073          * Initialize the new leaf block.
1074          */
1075         error = xfs_dir2_leaf_init(args, XFS_DIR2_DA_TO_DB(mp, blkno),
1076                 &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1077         if (error) {
1078                 return error;
1079         }
1080         newblk->blkno = blkno;
1081         newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1082         /*
1083          * Rebalance the entries across the two leaves, link the new
1084          * block into the leaves.
1085          */
1086         xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1087         error = xfs_da_blk_link(state, oldblk, newblk);
1088         if (error) {
1089                 return error;
1090         }
1091         /*
1092          * Insert the new entry in the correct block.
1093          */
1094         if (state->inleaf)
1095                 error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1096         else
1097                 error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1098         /*
1099          * Update last hashval in each block since we added the name.
1100          */
1101         oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1102         newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1103         xfs_dir2_leafn_check(args->dp, oldblk->bp);
1104         xfs_dir2_leafn_check(args->dp, newblk->bp);
1105         return error;
1106 }
1107
1108 /*
1109  * Check a leaf block and its neighbors to see if the block should be
1110  * collapsed into one or the other neighbor.  Always keep the block
1111  * with the smaller block number.
1112  * If the current block is over 50% full, don't try to join it, return 0.
1113  * If the block is empty, fill in the state structure and return 2.
1114  * If it can be collapsed, fill in the state structure and return 1.
1115  * If nothing can be done, return 0.
1116  */
1117 int                                             /* error */
1118 xfs_dir2_leafn_toosmall(
1119         xfs_da_state_t          *state,         /* btree cursor */
1120         int                     *action)        /* resulting action to take */
1121 {
1122         xfs_da_state_blk_t      *blk;           /* leaf block */
1123         xfs_dablk_t             blkno;          /* leaf block number */
1124         xfs_dabuf_t             *bp;            /* leaf buffer */
1125         int                     bytes;          /* bytes in use */
1126         int                     count;          /* leaf live entry count */
1127         int                     error;          /* error return value */
1128         int                     forward;        /* sibling block direction */
1129         int                     i;              /* sibling counter */
1130         xfs_da_blkinfo_t        *info;          /* leaf block header */
1131         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1132         int                     rval;           /* result from path_shift */
1133
1134         /*
1135          * Check for the degenerate case of the block being over 50% full.
1136          * If so, it's not worth even looking to see if we might be able
1137          * to coalesce with a sibling.
1138          */
1139         blk = &state->path.blk[state->path.active - 1];
1140         info = blk->bp->data;
1141         ASSERT(INT_GET(info->magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1142         leaf = (xfs_dir2_leaf_t *)info;
1143         count = INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1144         bytes = (uint)sizeof(leaf->hdr) + count * (uint)sizeof(leaf->ents[0]);
1145         if (bytes > (state->blocksize >> 1)) {
1146                 /*
1147                  * Blk over 50%, don't try to join.
1148                  */
1149                 *action = 0;
1150                 return 0;
1151         }
1152         /*
1153          * Check for the degenerate case of the block being empty.
1154          * If the block is empty, we'll simply delete it, no need to
1155          * coalesce it with a sibling block.  We choose (arbitrarily)
1156          * to merge with the forward block unless it is NULL.
1157          */
1158         if (count == 0) {
1159                 /*
1160                  * Make altpath point to the block we want to keep and
1161                  * path point to the block we want to drop (this one).
1162                  */
1163                 forward = info->forw;
1164                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1165                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1166                         &rval);
1167                 if (error)
1168                         return error;
1169                 *action = rval ? 2 : 0;
1170                 return 0;
1171         }
1172         /*
1173          * Examine each sibling block to see if we can coalesce with
1174          * at least 25% free space to spare.  We need to figure out
1175          * whether to merge with the forward or the backward block.
1176          * We prefer coalescing with the lower numbered sibling so as
1177          * to shrink a directory over time.
1178          */
1179         forward = INT_GET(info->forw, ARCH_CONVERT) < INT_GET(info->back, ARCH_CONVERT);
1180         for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1181                 blkno = forward ?INT_GET( info->forw, ARCH_CONVERT) : INT_GET(info->back, ARCH_CONVERT);
1182                 if (blkno == 0)
1183                         continue;
1184                 /*
1185                  * Read the sibling leaf block.
1186                  */
1187                 if ((error =
1188                     xfs_da_read_buf(state->args->trans, state->args->dp, blkno,
1189                             -1, &bp, XFS_DATA_FORK))) {
1190                         return error;
1191                 }
1192                 ASSERT(bp != NULL);
1193                 /*
1194                  * Count bytes in the two blocks combined.
1195                  */
1196                 leaf = (xfs_dir2_leaf_t *)info;
1197                 count = INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1198                 bytes = state->blocksize - (state->blocksize >> 2);
1199                 leaf = bp->data;
1200                 ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1201                 count += INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1202                 bytes -= count * (uint)sizeof(leaf->ents[0]);
1203                 /*
1204                  * Fits with at least 25% to spare.
1205                  */
1206                 if (bytes >= 0)
1207                         break;
1208                 xfs_da_brelse(state->args->trans, bp);
1209         }
1210         /*
1211          * Didn't like either block, give up.
1212          */
1213         if (i >= 2) {
1214                 *action = 0;
1215                 return 0;
1216         }
1217         /*
1218          * Done with the sibling leaf block here, drop the dabuf
1219          * so path_shift can get it.
1220          */
1221         xfs_da_buf_done(bp);
1222         /*
1223          * Make altpath point to the block we want to keep (the lower
1224          * numbered block) and path point to the block we want to drop.
1225          */
1226         memcpy(&state->altpath, &state->path, sizeof(state->path));
1227         if (blkno < blk->blkno)
1228                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1229                         &rval);
1230         else
1231                 error = xfs_da_path_shift(state, &state->path, forward, 0,
1232                         &rval);
1233         if (error) {
1234                 return error;
1235         }
1236         *action = rval ? 0 : 1;
1237         return 0;
1238 }
1239
1240 /*
1241  * Move all the leaf entries from drop_blk to save_blk.
1242  * This is done as part of a join operation.
1243  */
1244 void
1245 xfs_dir2_leafn_unbalance(
1246         xfs_da_state_t          *state,         /* cursor */
1247         xfs_da_state_blk_t      *drop_blk,      /* dead block */
1248         xfs_da_state_blk_t      *save_blk)      /* surviving block */
1249 {
1250         xfs_da_args_t           *args;          /* operation arguments */
1251         xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1252         xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1253
1254         args = state->args;
1255         ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1256         ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1257         drop_leaf = drop_blk->bp->data;
1258         save_leaf = save_blk->bp->data;
1259         ASSERT(INT_GET(drop_leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1260         ASSERT(INT_GET(save_leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1261         /*
1262          * If there are any stale leaf entries, take this opportunity
1263          * to purge them.
1264          */
1265         if (INT_GET(drop_leaf->hdr.stale, ARCH_CONVERT))
1266                 xfs_dir2_leaf_compact(args, drop_blk->bp);
1267         if (INT_GET(save_leaf->hdr.stale, ARCH_CONVERT))
1268                 xfs_dir2_leaf_compact(args, save_blk->bp);
1269         /*
1270          * Move the entries from drop to the appropriate end of save.
1271          */
1272         drop_blk->hashval = INT_GET(drop_leaf->ents[INT_GET(drop_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1273         if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1274                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp, 0,
1275                         INT_GET(drop_leaf->hdr.count, ARCH_CONVERT));
1276         else
1277                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp,
1278                         INT_GET(save_leaf->hdr.count, ARCH_CONVERT), INT_GET(drop_leaf->hdr.count, ARCH_CONVERT));
1279         save_blk->hashval = INT_GET(save_leaf->ents[INT_GET(save_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1280         xfs_dir2_leafn_check(args->dp, save_blk->bp);
1281 }
1282
1283 /*
1284  * Top-level node form directory addname routine.
1285  */
1286 int                                             /* error */
1287 xfs_dir2_node_addname(
1288         xfs_da_args_t           *args)          /* operation arguments */
1289 {
1290         xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1291         int                     error;          /* error return value */
1292         int                     rval;           /* sub-return value */
1293         xfs_da_state_t          *state;         /* btree cursor */
1294
1295         xfs_dir2_trace_args("node_addname", args);
1296         /*
1297          * Allocate and initialize the state (btree cursor).
1298          */
1299         state = xfs_da_state_alloc();
1300         state->args = args;
1301         state->mp = args->dp->i_mount;
1302         state->blocksize = state->mp->m_dirblksize;
1303         state->node_ents = state->mp->m_dir_node_ents;
1304         /*
1305          * Look up the name.  We're not supposed to find it, but
1306          * this gives us the insertion point.
1307          */
1308         error = xfs_da_node_lookup_int(state, &rval);
1309         if (error)
1310                 rval = error;
1311         if (rval != ENOENT) {
1312                 goto done;
1313         }
1314         /*
1315          * Add the data entry to a data block.
1316          * Extravalid is set to a freeblock found by lookup.
1317          */
1318         rval = xfs_dir2_node_addname_int(args,
1319                 state->extravalid ? &state->extrablk : NULL);
1320         if (rval) {
1321                 goto done;
1322         }
1323         blk = &state->path.blk[state->path.active - 1];
1324         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1325         /*
1326          * Add the new leaf entry.
1327          */
1328         rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1329         if (rval == 0) {
1330                 /*
1331                  * It worked, fix the hash values up the btree.
1332                  */
1333                 if (!args->justcheck)
1334                         xfs_da_fixhashpath(state, &state->path);
1335         } else {
1336                 /*
1337                  * It didn't work, we need to split the leaf block.
1338                  */
1339                 if (args->total == 0) {
1340                         ASSERT(rval == ENOSPC);
1341                         goto done;
1342                 }
1343                 /*
1344                  * Split the leaf block and insert the new entry.
1345                  */
1346                 rval = xfs_da_split(state);
1347         }
1348 done:
1349         xfs_da_state_free(state);
1350         return rval;
1351 }
1352
1353 /*
1354  * Add the data entry for a node-format directory name addition.
1355  * The leaf entry is added in xfs_dir2_leafn_add.
1356  * We may enter with a freespace block that the lookup found.
1357  */
1358 static int                                      /* error */
1359 xfs_dir2_node_addname_int(
1360         xfs_da_args_t           *args,          /* operation arguments */
1361         xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1362 {
1363         xfs_dir2_data_t         *data;          /* data block structure */
1364         xfs_dir2_db_t           dbno;           /* data block number */
1365         xfs_dabuf_t             *dbp;           /* data block buffer */
1366         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1367         xfs_inode_t             *dp;            /* incore directory inode */
1368         xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1369         int                     error;          /* error return value */
1370         xfs_dir2_db_t           fbno;           /* freespace block number */
1371         xfs_dabuf_t             *fbp;           /* freespace buffer */
1372         int                     findex;         /* freespace entry index */
1373         xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1374         xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1375         xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1376         int                     length;         /* length of the new entry */
1377         int                     logfree;        /* need to log free entry */
1378         xfs_mount_t             *mp;            /* filesystem mount point */
1379         int                     needlog;        /* need to log data header */
1380         int                     needscan;       /* need to rescan data frees */
1381         xfs_dir2_data_off_t     *tagp;          /* data entry tag pointer */
1382         xfs_trans_t             *tp;            /* transaction pointer */
1383
1384         dp = args->dp;
1385         mp = dp->i_mount;
1386         tp = args->trans;
1387         length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
1388         /*
1389          * If we came in with a freespace block that means that lookup
1390          * found an entry with our hash value.  This is the freespace
1391          * block for that data entry.
1392          */
1393         if (fblk) {
1394                 fbp = fblk->bp;
1395                 /*
1396                  * Remember initial freespace block number.
1397                  */
1398                 ifbno = fblk->blkno;
1399                 free = fbp->data;
1400                 ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1401                 findex = fblk->index;
1402                 /*
1403                  * This means the free entry showed that the data block had
1404                  * space for our entry, so we remembered it.
1405                  * Use that data block.
1406                  */
1407                 if (findex >= 0) {
1408                         ASSERT(findex < INT_GET(free->hdr.nvalid, ARCH_CONVERT));
1409                         ASSERT(INT_GET(free->bests[findex], ARCH_CONVERT) != NULLDATAOFF);
1410                         ASSERT(INT_GET(free->bests[findex], ARCH_CONVERT) >= length);
1411                         dbno = INT_GET(free->hdr.firstdb, ARCH_CONVERT) + findex;
1412                 }
1413                 /*
1414                  * The data block looked at didn't have enough room.
1415                  * We'll start at the beginning of the freespace entries.
1416                  */
1417                 else {
1418                         dbno = -1;
1419                         findex = 0;
1420                 }
1421         }
1422         /*
1423          * Didn't come in with a freespace block, so don't have a data block.
1424          */
1425         else {
1426                 ifbno = dbno = -1;
1427                 fbp = NULL;
1428                 findex = 0;
1429         }
1430         /*
1431          * If we don't have a data block yet, we're going to scan the
1432          * freespace blocks looking for one.  Figure out what the
1433          * highest freespace block number is.
1434          */
1435         if (dbno == -1) {
1436                 xfs_fileoff_t   fo;             /* freespace block number */
1437
1438                 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1439                         return error;
1440                 lastfbno = XFS_DIR2_DA_TO_DB(mp, (xfs_dablk_t)fo);
1441                 fbno = ifbno;
1442         }
1443         /*
1444          * While we haven't identified a data block, search the freeblock
1445          * data for a good data block.  If we find a null freeblock entry,
1446          * indicating a hole in the data blocks, remember that.
1447          */
1448         while (dbno == -1) {
1449                 /*
1450                  * If we don't have a freeblock in hand, get the next one.
1451                  */
1452                 if (fbp == NULL) {
1453                         /*
1454                          * Happens the first time through unless lookup gave
1455                          * us a freespace block to start with.
1456                          */
1457                         if (++fbno == 0)
1458                                 fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1459                         /*
1460                          * If it's ifbno we already looked at it.
1461                          */
1462                         if (fbno == ifbno)
1463                                 fbno++;
1464                         /*
1465                          * If it's off the end we're done.
1466                          */
1467                         if (fbno >= lastfbno)
1468                                 break;
1469                         /*
1470                          * Read the block.  There can be holes in the
1471                          * freespace blocks, so this might not succeed.
1472                          * This should be really rare, so there's no reason
1473                          * to avoid it.
1474                          */
1475                         if ((error = xfs_da_read_buf(tp, dp,
1476                                         XFS_DIR2_DB_TO_DA(mp, fbno), -2, &fbp,
1477                                         XFS_DATA_FORK))) {
1478                                 return error;
1479                         }
1480                         if (unlikely(fbp == NULL)) {
1481                                 continue;
1482                         }
1483                         free = fbp->data;
1484                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1485                         findex = 0;
1486                 }
1487                 /*
1488                  * Look at the current free entry.  Is it good enough?
1489                  */
1490                 if (INT_GET(free->bests[findex], ARCH_CONVERT) != NULLDATAOFF &&
1491                     INT_GET(free->bests[findex], ARCH_CONVERT) >= length)
1492                         dbno = INT_GET(free->hdr.firstdb, ARCH_CONVERT) + findex;
1493                 else {
1494                         /*
1495                          * Are we done with the freeblock?
1496                          */
1497                         if (++findex == INT_GET(free->hdr.nvalid, ARCH_CONVERT)) {
1498                                 /*
1499                                  * Drop the block.
1500                                  */
1501                                 xfs_da_brelse(tp, fbp);
1502                                 fbp = NULL;
1503                                 if (fblk && fblk->bp)
1504                                         fblk->bp = NULL;
1505                         }
1506                 }
1507         }
1508         /*
1509          * If we don't have a data block, we need to allocate one and make
1510          * the freespace entries refer to it.
1511          */
1512         if (unlikely(dbno == -1)) {
1513                 /*
1514                  * Not allowed to allocate, return failure.
1515                  */
1516                 if (args->justcheck || args->total == 0) {
1517                         /*
1518                          * Drop the freespace buffer unless it came from our
1519                          * caller.
1520                          */
1521                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1522                                 xfs_da_buf_done(fbp);
1523                         return XFS_ERROR(ENOSPC);
1524                 }
1525                 /*
1526                  * Allocate and initialize the new data block.
1527                  */
1528                 if (unlikely((error = xfs_dir2_grow_inode(args,
1529                                                          XFS_DIR2_DATA_SPACE,
1530                                                          &dbno)) ||
1531                     (error = xfs_dir2_data_init(args, dbno, &dbp)))) {
1532                         /*
1533                          * Drop the freespace buffer unless it came from our
1534                          * caller.
1535                          */
1536                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1537                                 xfs_da_buf_done(fbp);
1538                         return error;
1539                 }
1540                 /*
1541                  * If (somehow) we have a freespace block, get rid of it.
1542                  */
1543                 if (fbp)
1544                         xfs_da_brelse(tp, fbp);
1545                 if (fblk && fblk->bp)
1546                         fblk->bp = NULL;
1547
1548                 /*
1549                  * Get the freespace block corresponding to the data block
1550                  * that was just allocated.
1551                  */
1552                 fbno = XFS_DIR2_DB_TO_FDB(mp, dbno);
1553                 if (unlikely(error = xfs_da_read_buf(tp, dp,
1554                                 XFS_DIR2_DB_TO_DA(mp, fbno), -2, &fbp,
1555                                 XFS_DATA_FORK))) {
1556                         xfs_da_buf_done(dbp);
1557                         return error;
1558                 }
1559                 /*
1560                  * If there wasn't a freespace block, the read will
1561                  * return a NULL fbp.  Allocate and initialize a new one.
1562                  */
1563                 if( fbp == NULL ) {
1564                         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1565                                                         &fbno))) {
1566                                 return error;
1567                         }
1568
1569                         if (unlikely(XFS_DIR2_DB_TO_FDB(mp, dbno) != fbno)) {
1570                                 cmn_err(CE_ALERT,
1571                                         "xfs_dir2_node_addname_int: dir ino "
1572                                         "%llu needed freesp block %lld for\n"
1573                                         "  data block %lld, got %lld\n"
1574                                         "  ifbno %llu lastfbno %d\n",
1575                                         (unsigned long long)dp->i_ino,
1576                                         (long long)XFS_DIR2_DB_TO_FDB(mp, dbno),
1577                                         (long long)dbno, (long long)fbno,
1578                                         (unsigned long long)ifbno, lastfbno);
1579                                 if (fblk) {
1580                                         cmn_err(CE_ALERT,
1581                                                 " fblk 0x%p blkno %llu "
1582                                                 "index %d magic 0x%x\n",
1583                                                 fblk,
1584                                                 (unsigned long long)fblk->blkno,
1585                                                 fblk->index,
1586                                                 fblk->magic);
1587                                 } else {
1588                                         cmn_err(CE_ALERT,
1589                                                 " ... fblk is NULL\n");
1590                                 }
1591                                 XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1592                                                  XFS_ERRLEVEL_LOW, mp);
1593                                 return XFS_ERROR(EFSCORRUPTED);
1594                         }
1595
1596                         /*
1597                          * Get a buffer for the new block.
1598                          */
1599                         if ((error = xfs_da_get_buf(tp, dp,
1600                                                    XFS_DIR2_DB_TO_DA(mp, fbno),
1601                                                    -1, &fbp, XFS_DATA_FORK))) {
1602                                 return error;
1603                         }
1604                         ASSERT(fbp != NULL);
1605
1606                         /*
1607                          * Initialize the new block to be empty, and remember
1608                          * its first slot as our empty slot.
1609                          */
1610                         free = fbp->data;
1611                         INT_SET(free->hdr.magic, ARCH_CONVERT, XFS_DIR2_FREE_MAGIC);
1612                         INT_SET(free->hdr.firstdb, ARCH_CONVERT,
1613                                 (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1614                                 XFS_DIR2_MAX_FREE_BESTS(mp));
1615                         free->hdr.nvalid = 0;
1616                         free->hdr.nused = 0;
1617                 } else {
1618                         free = fbp->data;
1619                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1620                 }
1621
1622                 /*
1623                  * Set the freespace block index from the data block number.
1624                  */
1625                 findex = XFS_DIR2_DB_TO_FDINDEX(mp, dbno);
1626                 /*
1627                  * If it's after the end of the current entries in the
1628                  * freespace block, extend that table.
1629                  */
1630                 if (findex >= INT_GET(free->hdr.nvalid, ARCH_CONVERT)) {
1631                         ASSERT(findex < XFS_DIR2_MAX_FREE_BESTS(mp));
1632                         INT_SET(free->hdr.nvalid, ARCH_CONVERT, findex + 1);
1633                         /*
1634                          * Tag new entry so nused will go up.
1635                          */
1636                         INT_SET(free->bests[findex], ARCH_CONVERT, NULLDATAOFF);
1637                 }
1638                 /*
1639                  * If this entry was for an empty data block
1640                  * (this should always be true) then update the header.
1641                  */
1642                 if (INT_GET(free->bests[findex], ARCH_CONVERT) == NULLDATAOFF) {
1643                         INT_MOD(free->hdr.nused, ARCH_CONVERT, +1);
1644                         xfs_dir2_free_log_header(tp, fbp);
1645                 }
1646                 /*
1647                  * Update the real value in the table.
1648                  * We haven't allocated the data entry yet so this will
1649                  * change again.
1650                  */
1651                 data = dbp->data;
1652                 INT_COPY(free->bests[findex], data->hdr.bestfree[0].length, ARCH_CONVERT);
1653                 logfree = 1;
1654         }
1655         /*
1656          * We had a data block so we don't have to make a new one.
1657          */
1658         else {
1659                 /*
1660                  * If just checking, we succeeded.
1661                  */
1662                 if (args->justcheck) {
1663                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1664                                 xfs_da_buf_done(fbp);
1665                         return 0;
1666                 }
1667                 /*
1668                  * Read the data block in.
1669                  */
1670                 if (unlikely(
1671                     error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, dbno),
1672                                 -1, &dbp, XFS_DATA_FORK))) {
1673                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1674                                 xfs_da_buf_done(fbp);
1675                         return error;
1676                 }
1677                 data = dbp->data;
1678                 logfree = 0;
1679         }
1680         ASSERT(INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT) >= length);
1681         /*
1682          * Point to the existing unused space.
1683          */
1684         dup = (xfs_dir2_data_unused_t *)
1685               ((char *)data + INT_GET(data->hdr.bestfree[0].offset, ARCH_CONVERT));
1686         needscan = needlog = 0;
1687         /*
1688          * Mark the first part of the unused space, inuse for us.
1689          */
1690         xfs_dir2_data_use_free(tp, dbp, dup,
1691                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)data), length,
1692                 &needlog, &needscan);
1693         /*
1694          * Fill in the new entry and log it.
1695          */
1696         dep = (xfs_dir2_data_entry_t *)dup;
1697         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
1698         dep->namelen = args->namelen;
1699         memcpy(dep->name, args->name, dep->namelen);
1700         tagp = XFS_DIR2_DATA_ENTRY_TAG_P(dep);
1701         INT_SET(*tagp, ARCH_CONVERT, (xfs_dir2_data_off_t)((char *)dep - (char *)data));
1702         xfs_dir2_data_log_entry(tp, dbp, dep);
1703         /*
1704          * Rescan the block for bestfree if needed.
1705          */
1706         if (needscan)
1707                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
1708         /*
1709          * Log the data block header if needed.
1710          */
1711         if (needlog)
1712                 xfs_dir2_data_log_header(tp, dbp);
1713         /*
1714          * If the freespace entry is now wrong, update it.
1715          */
1716         if (INT_GET(free->bests[findex], ARCH_CONVERT) != INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT)) {
1717                 INT_COPY(free->bests[findex], data->hdr.bestfree[0].length, ARCH_CONVERT);
1718                 logfree = 1;
1719         }
1720         /*
1721          * Log the freespace entry if needed.
1722          */
1723         if (logfree)
1724                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1725         /*
1726          * If the caller didn't hand us the freespace block, drop it.
1727          */
1728         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1729                 xfs_da_buf_done(fbp);
1730         /*
1731          * Return the data block and offset in args, then drop the data block.
1732          */
1733         args->blkno = (xfs_dablk_t)dbno;
1734         args->index = INT_GET(*tagp, ARCH_CONVERT);
1735         xfs_da_buf_done(dbp);
1736         return 0;
1737 }
1738
1739 /*
1740  * Lookup an entry in a node-format directory.
1741  * All the real work happens in xfs_da_node_lookup_int.
1742  * The only real output is the inode number of the entry.
1743  */
1744 int                                             /* error */
1745 xfs_dir2_node_lookup(
1746         xfs_da_args_t   *args)                  /* operation arguments */
1747 {
1748         int             error;                  /* error return value */
1749         int             i;                      /* btree level */
1750         int             rval;                   /* operation return value */
1751         xfs_da_state_t  *state;                 /* btree cursor */
1752
1753         xfs_dir2_trace_args("node_lookup", args);
1754         /*
1755          * Allocate and initialize the btree cursor.
1756          */
1757         state = xfs_da_state_alloc();
1758         state->args = args;
1759         state->mp = args->dp->i_mount;
1760         state->blocksize = state->mp->m_dirblksize;
1761         state->node_ents = state->mp->m_dir_node_ents;
1762         /*
1763          * Fill in the path to the entry in the cursor.
1764          */
1765         error = xfs_da_node_lookup_int(state, &rval);
1766         if (error)
1767                 rval = error;
1768         /*
1769          * Release the btree blocks and leaf block.
1770          */
1771         for (i = 0; i < state->path.active; i++) {
1772                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1773                 state->path.blk[i].bp = NULL;
1774         }
1775         /*
1776          * Release the data block if we have it.
1777          */
1778         if (state->extravalid && state->extrablk.bp) {
1779                 xfs_da_brelse(args->trans, state->extrablk.bp);
1780                 state->extrablk.bp = NULL;
1781         }
1782         xfs_da_state_free(state);
1783         return rval;
1784 }
1785
1786 /*
1787  * Remove an entry from a node-format directory.
1788  */
1789 int                                             /* error */
1790 xfs_dir2_node_removename(
1791         xfs_da_args_t           *args)          /* operation arguments */
1792 {
1793         xfs_da_state_blk_t      *blk;           /* leaf block */
1794         int                     error;          /* error return value */
1795         int                     rval;           /* operation return value */
1796         xfs_da_state_t          *state;         /* btree cursor */
1797
1798         xfs_dir2_trace_args("node_removename", args);
1799         /*
1800          * Allocate and initialize the btree cursor.
1801          */
1802         state = xfs_da_state_alloc();
1803         state->args = args;
1804         state->mp = args->dp->i_mount;
1805         state->blocksize = state->mp->m_dirblksize;
1806         state->node_ents = state->mp->m_dir_node_ents;
1807         /*
1808          * Look up the entry we're deleting, set up the cursor.
1809          */
1810         error = xfs_da_node_lookup_int(state, &rval);
1811         if (error) {
1812                 rval = error;
1813         }
1814         /*
1815          * Didn't find it, upper layer screwed up.
1816          */
1817         if (rval != EEXIST) {
1818                 xfs_da_state_free(state);
1819                 return rval;
1820         }
1821         blk = &state->path.blk[state->path.active - 1];
1822         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1823         ASSERT(state->extravalid);
1824         /*
1825          * Remove the leaf and data entries.
1826          * Extrablk refers to the data block.
1827          */
1828         error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
1829                 &state->extrablk, &rval);
1830         if (error) {
1831                 return error;
1832         }
1833         /*
1834          * Fix the hash values up the btree.
1835          */
1836         xfs_da_fixhashpath(state, &state->path);
1837         /*
1838          * If we need to join leaf blocks, do it.
1839          */
1840         if (rval && state->path.active > 1)
1841                 error = xfs_da_join(state);
1842         /*
1843          * If no errors so far, try conversion to leaf format.
1844          */
1845         if (!error)
1846                 error = xfs_dir2_node_to_leaf(state);
1847         xfs_da_state_free(state);
1848         return error;
1849 }
1850
1851 /*
1852  * Replace an entry's inode number in a node-format directory.
1853  */
1854 int                                             /* error */
1855 xfs_dir2_node_replace(
1856         xfs_da_args_t           *args)          /* operation arguments */
1857 {
1858         xfs_da_state_blk_t      *blk;           /* leaf block */
1859         xfs_dir2_data_t         *data;          /* data block structure */
1860         xfs_dir2_data_entry_t   *dep;           /* data entry changed */
1861         int                     error;          /* error return value */
1862         int                     i;              /* btree level */
1863         xfs_ino_t               inum;           /* new inode number */
1864         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1865         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
1866         int                     rval;           /* internal return value */
1867         xfs_da_state_t          *state;         /* btree cursor */
1868
1869         xfs_dir2_trace_args("node_replace", args);
1870         /*
1871          * Allocate and initialize the btree cursor.
1872          */
1873         state = xfs_da_state_alloc();
1874         state->args = args;
1875         state->mp = args->dp->i_mount;
1876         state->blocksize = state->mp->m_dirblksize;
1877         state->node_ents = state->mp->m_dir_node_ents;
1878         inum = args->inumber;
1879         /*
1880          * Lookup the entry to change in the btree.
1881          */
1882         error = xfs_da_node_lookup_int(state, &rval);
1883         if (error) {
1884                 rval = error;
1885         }
1886         /*
1887          * It should be found, since the vnodeops layer has looked it up
1888          * and locked it.  But paranoia is good.
1889          */
1890         if (rval == EEXIST) {
1891                 /*
1892                  * Find the leaf entry.
1893                  */
1894                 blk = &state->path.blk[state->path.active - 1];
1895                 ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1896                 leaf = blk->bp->data;
1897                 lep = &leaf->ents[blk->index];
1898                 ASSERT(state->extravalid);
1899                 /*
1900                  * Point to the data entry.
1901                  */
1902                 data = state->extrablk.bp->data;
1903                 ASSERT(INT_GET(data->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC);
1904                 dep = (xfs_dir2_data_entry_t *)
1905                       ((char *)data +
1906                        XFS_DIR2_DATAPTR_TO_OFF(state->mp, INT_GET(lep->address, ARCH_CONVERT)));
1907                 ASSERT(inum != INT_GET(dep->inumber, ARCH_CONVERT));
1908                 /*
1909                  * Fill in the new inode number and log the entry.
1910                  */
1911                 INT_SET(dep->inumber, ARCH_CONVERT, inum);
1912                 xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
1913                 rval = 0;
1914         }
1915         /*
1916          * Didn't find it, and we're holding a data block.  Drop it.
1917          */
1918         else if (state->extravalid) {
1919                 xfs_da_brelse(args->trans, state->extrablk.bp);
1920                 state->extrablk.bp = NULL;
1921         }
1922         /*
1923          * Release all the buffers in the cursor.
1924          */
1925         for (i = 0; i < state->path.active; i++) {
1926                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1927                 state->path.blk[i].bp = NULL;
1928         }
1929         xfs_da_state_free(state);
1930         return rval;
1931 }
1932
1933 /*
1934  * Trim off a trailing empty freespace block.
1935  * Return (in rvalp) 1 if we did it, 0 if not.
1936  */
1937 int                                             /* error */
1938 xfs_dir2_node_trim_free(
1939         xfs_da_args_t           *args,          /* operation arguments */
1940         xfs_fileoff_t           fo,             /* free block number */
1941         int                     *rvalp)         /* out: did something */
1942 {
1943         xfs_dabuf_t             *bp;            /* freespace buffer */
1944         xfs_inode_t             *dp;            /* incore directory inode */
1945         int                     error;          /* error return code */
1946         xfs_dir2_free_t         *free;          /* freespace structure */
1947         xfs_mount_t             *mp;            /* filesystem mount point */
1948         xfs_trans_t             *tp;            /* transaction pointer */
1949
1950         dp = args->dp;
1951         mp = dp->i_mount;
1952         tp = args->trans;
1953         /*
1954          * Read the freespace block.
1955          */
1956         if (unlikely(error = xfs_da_read_buf(tp, dp, (xfs_dablk_t)fo, -2, &bp,
1957                         XFS_DATA_FORK))) {
1958                 return error;
1959         }
1960
1961         /*
1962          * There can be holes in freespace.  If fo is a hole, there's
1963          * nothing to do.
1964          */
1965         if (bp == NULL) {
1966                 return 0;
1967         }
1968         free = bp->data;
1969         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1970         /*
1971          * If there are used entries, there's nothing to do.
1972          */
1973         if (INT_GET(free->hdr.nused, ARCH_CONVERT) > 0) {
1974                 xfs_da_brelse(tp, bp);
1975                 *rvalp = 0;
1976                 return 0;
1977         }
1978         /*
1979          * Blow the block away.
1980          */
1981         if ((error =
1982             xfs_dir2_shrink_inode(args, XFS_DIR2_DA_TO_DB(mp, (xfs_dablk_t)fo),
1983                     bp))) {
1984                 /*
1985                  * Can't fail with ENOSPC since that only happens with no
1986                  * space reservation, when breaking up an extent into two
1987                  * pieces.  This is the last block of an extent.
1988                  */
1989                 ASSERT(error != ENOSPC);
1990                 xfs_da_brelse(tp, bp);
1991                 return error;
1992         }
1993         /*
1994          * Return that we succeeded.
1995          */
1996         *rvalp = 1;
1997         return 0;
1998 }