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   1 /*
   2  * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of version 2 of the GNU General Public License as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it would be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11  *
  12  * Further, this software is distributed without any warranty that it is
  13  * free of the rightful claim of any third person regarding infringement
  14  * or the like.  Any license provided herein, whether implied or
  15  * otherwise, applies only to this software file.  Patent licenses, if
  16  * any, provided herein do not apply to combinations of this program with
  17  * other software, or any other product whatsoever.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write the Free Software Foundation, Inc., 59
  21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22  *
  23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24  * Mountain View, CA  94043, or:
  25  *
  26  * http://www.sgi.com
  27  *
  28  * For further information regarding this notice, see:
  29  *
  30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31  */
  32
  33 /*
  34  * xfs_dir2_node.c
  35  * XFS directory implementation, version 2, node form files
  36  * See data structures in xfs_dir2_node.h and xfs_da_btree.h.
  37  */
  38
  39 #include "xfs.h"
  40
  41 #include "xfs_macros.h"
  42 #include "xfs_types.h"
  43 #include "xfs_inum.h"
  44 #include "xfs_log.h"
  45 #include "xfs_trans.h"
  46 #include "xfs_sb.h"
  47 #include "xfs_dir.h"
  48 #include "xfs_dir2.h"
  49 #include "xfs_dmapi.h"
  50 #include "xfs_mount.h"
  51 #include "xfs_bmap_btree.h"
  52 #include "xfs_attr_sf.h"
  53 #include "xfs_dir_sf.h"
  54 #include "xfs_dir2_sf.h"
  55 #include "xfs_dinode.h"
  56 #include "xfs_inode.h"
  57 #include "xfs_bmap.h"
  58 #include "xfs_da_btree.h"
  59 #include "xfs_dir2_data.h"
  60 #include "xfs_dir2_leaf.h"
  61 #include "xfs_dir2_block.h"
  62 #include "xfs_dir2_node.h"
  63 #include "xfs_dir2_trace.h"
  64 #include "xfs_error.h"
  65
  66 /*
  67  * Function declarations.
  68  */
  69 static void xfs_dir2_free_log_header(xfs_trans_t *tp, xfs_dabuf_t *bp);
  70 static int xfs_dir2_leafn_add(xfs_dabuf_t *bp, xfs_da_args_t *args, int index);
  71 #ifdef DEBUG
  72 static void xfs_dir2_leafn_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
  73 #else
  74 #define xfs_dir2_leafn_check(dp, bp)
  75 #endif
  76 static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, xfs_dabuf_t *bp_s,
  77                                     int start_s, xfs_dabuf_t *bp_d, int start_d,
  78                                     int count);
  79 static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  80                                      xfs_da_state_blk_t *blk1,
  81                                      xfs_da_state_blk_t *blk2);
  82 static int xfs_dir2_leafn_remove(xfs_da_args_t *args, xfs_dabuf_t *bp,
  83                                  int index, xfs_da_state_blk_t *dblk,
  84                                  int *rval);
  85 static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  86                                      xfs_da_state_blk_t *fblk);
  87
  88 /*
  89  * Log entries from a freespace block.
  90  */
  91 void
  92 xfs_dir2_free_log_bests(
  93         xfs_trans_t             *tp,            /* transaction pointer */
  94         xfs_dabuf_t             *bp,            /* freespace buffer */
  95         int                     first,          /* first entry to log */
  96         int                     last)           /* last entry to log */
  97 {
  98         xfs_dir2_free_t         *free;          /* freespace structure */
  99
 100         free = bp->data;
 101         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 102         xfs_da_log_buf(tp, bp,
 103                 (uint)((char *)&free->bests[first] - (char *)free),
 104                 (uint)((char *)&free->bests[last] - (char *)free +
 105                        sizeof(free->bests[0]) - 1));
 106 }
 107
 108 /*
 109  * Log header from a freespace block.
 110  */
 111 static void
 112 xfs_dir2_free_log_header(
 113         xfs_trans_t             *tp,            /* transaction pointer */
 114         xfs_dabuf_t             *bp)            /* freespace buffer */
 115 {
 116         xfs_dir2_free_t         *free;          /* freespace structure */
 117
 118         free = bp->data;
 119         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 120         xfs_da_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
 121                 (uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
 122 }
 123
 124 /*
 125  * Convert a leaf-format directory to a node-format directory.
 126  * We need to change the magic number of the leaf block, and copy
 127  * the freespace table out of the leaf block into its own block.
 128  */
 129 int                                             /* error */
 130 xfs_dir2_leaf_to_node(
 131         xfs_da_args_t           *args,          /* operation arguments */
 132         xfs_dabuf_t             *lbp)           /* leaf buffer */
 133 {
 134         xfs_inode_t             *dp;            /* incore directory inode */
 135         int                     error;          /* error return value */
 136         xfs_dabuf_t             *fbp;           /* freespace buffer */
 137         xfs_dir2_db_t           fdb;            /* freespace block number */
 138         xfs_dir2_free_t         *free;          /* freespace structure */
 139         xfs_dir2_data_off_t     *from;          /* pointer to freespace entry */
 140         int                     i;              /* leaf freespace index */
 141         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 142         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 143         xfs_mount_t             *mp;            /* filesystem mount point */
 144         int                     n;              /* count of live freespc ents */
 145         xfs_dir2_data_off_t     off;            /* freespace entry value */
 146         xfs_dir2_data_off_t     *to;            /* pointer to freespace entry */
 147         xfs_trans_t             *tp;            /* transaction pointer */
 148
 149         xfs_dir2_trace_args_b("leaf_to_node", args, lbp);
 150         dp = args->dp;
 151         mp = dp->i_mount;
 152         tp = args->trans;
 153         /*
 154          * Add a freespace block to the directory.
 155          */
 156         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 157                 return error;
 158         }
 159         ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 160         /*
 161          * Get the buffer for the new freespace block.
 162          */
 163         if ((error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb), -1, &fbp,
 164                         XFS_DATA_FORK))) {
 165                 return error;
 166         }
 167         ASSERT(fbp != NULL);
 168         free = fbp->data;
 169         leaf = lbp->data;
 170         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
 171         /*
 172          * Initialize the freespace block header.
 173          */
 174         INT_SET(free->hdr.magic, ARCH_CONVERT, XFS_DIR2_FREE_MAGIC);
 175         free->hdr.firstdb = 0;
 176         ASSERT(INT_GET(ltp->bestcount, ARCH_CONVERT) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
 177         INT_COPY(free->hdr.nvalid, ltp->bestcount, ARCH_CONVERT);
 178         /*
 179          * Copy freespace entries from the leaf block to the new block.
 180          * Count active entries.
 181          */
 182         for (i = n = 0, from = XFS_DIR2_LEAF_BESTS_P(ltp), to = free->bests;
 183              i < INT_GET(ltp->bestcount, ARCH_CONVERT); i++, from++, to++) {
 184                 if ((off = INT_GET(*from, ARCH_CONVERT)) != NULLDATAOFF)
 185                         n++;
 186                 INT_SET(*to, ARCH_CONVERT, off);
 187         }
 188         INT_SET(free->hdr.nused, ARCH_CONVERT, n);
 189         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, XFS_DIR2_LEAFN_MAGIC);
 190         /*
 191          * Log everything.
 192          */
 193         xfs_dir2_leaf_log_header(tp, lbp);
 194         xfs_dir2_free_log_header(tp, fbp);
 195         xfs_dir2_free_log_bests(tp, fbp, 0, INT_GET(free->hdr.nvalid, ARCH_CONVERT) - 1);
 196         xfs_da_buf_done(fbp);
 197         xfs_dir2_leafn_check(dp, lbp);
 198         return 0;
 199 }
 200
 201 /*
 202  * Add a leaf entry to a leaf block in a node-form directory.
 203  * The other work necessary is done from the caller.
 204  */
 205 static int                                      /* error */
 206 xfs_dir2_leafn_add(
 207         xfs_dabuf_t             *bp,            /* leaf buffer */
 208         xfs_da_args_t           *args,          /* operation arguments */
 209         int                     index)          /* insertion pt for new entry */
 210 {
 211         int                     compact;        /* compacting stale leaves */
 212         xfs_inode_t             *dp;            /* incore directory inode */
 213         int                     highstale;      /* next stale entry */
 214         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 215         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 216         int                     lfloghigh;      /* high leaf entry logging */
 217         int                     lfloglow;       /* low leaf entry logging */
 218         int                     lowstale;       /* previous stale entry */
 219         xfs_mount_t             *mp;            /* filesystem mount point */
 220         xfs_trans_t             *tp;            /* transaction pointer */
 221
 222         xfs_dir2_trace_args_sb("leafn_add", args, index, bp);
 223         dp = args->dp;
 224         mp = dp->i_mount;
 225         tp = args->trans;
 226         leaf = bp->data;
 227
 228         /*
 229          * Quick check just to make sure we are not going to index
 230          * into other peoples memory
 231          */
 232         if (index < 0)
 233                 return XFS_ERROR(EFSCORRUPTED);
 234
 235         /*
 236          * If there are already the maximum number of leaf entries in
 237          * the block, if there are no stale entries it won't fit.
 238          * Caller will do a split.  If there are stale entries we'll do
 239          * a compact.
 240          */
 241
 242         if (INT_GET(leaf->hdr.count, ARCH_CONVERT) == XFS_DIR2_MAX_LEAF_ENTS(mp)) {
 243                 if (!leaf->hdr.stale)
 244                         return XFS_ERROR(ENOSPC);
 245                 compact = INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1;
 246         } else
 247                 compact = 0;
 248         ASSERT(index == 0 || INT_GET(leaf->ents[index - 1].hashval, ARCH_CONVERT) <= args->hashval);
 249         ASSERT(index == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 250                INT_GET(leaf->ents[index].hashval, ARCH_CONVERT) >= args->hashval);
 251
 252         if (args->justcheck)
 253                 return 0;
 254
 255         /*
 256          * Compact out all but one stale leaf entry.  Leaves behind
 257          * the entry closest to index.
 258          */
 259         if (compact) {
 260                 xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
 261                         &lfloglow, &lfloghigh);
 262         }
 263         /*
 264          * Set impossible logging indices for this case.
 265          */
 266         else if (leaf->hdr.stale) {
 267                 lfloglow = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 268                 lfloghigh = -1;
 269         }
 270         /*
 271          * No stale entries, just insert a space for the new entry.
 272          */
 273         if (!leaf->hdr.stale) {
 274                 lep = &leaf->ents[index];
 275                 if (index < INT_GET(leaf->hdr.count, ARCH_CONVERT))
 276                         memmove(lep + 1, lep,
 277                                 (INT_GET(leaf->hdr.count, ARCH_CONVERT) - index) * sizeof(*lep));
 278                 lfloglow = index;
 279                 lfloghigh = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 280                 INT_MOD(leaf->hdr.count, ARCH_CONVERT, +1);
 281         }
 282         /*
 283          * There are stale entries.  We'll use one for the new entry.
 284          */
 285         else {
 286                 /*
 287                  * If we didn't do a compact then we need to figure out
 288                  * which stale entry will be used.
 289                  */
 290                 if (compact == 0) {
 291                         /*
 292                          * Find first stale entry before our insertion point.
 293                          */
 294                         for (lowstale = index - 1;
 295                              lowstale >= 0 &&
 296                                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) !=
 297                                 XFS_DIR2_NULL_DATAPTR;
 298                              lowstale--)
 299                                 continue;
 300                         /*
 301                          * Find next stale entry after insertion point.
 302                          * Stop looking if the answer would be worse than
 303                          * lowstale already found.
 304                          */
 305                         for (highstale = index;
 306                              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
 307                                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) !=
 308                                 XFS_DIR2_NULL_DATAPTR &&
 309                                 (lowstale < 0 ||
 310                                  index - lowstale - 1 >= highstale - index);
 311                              highstale++)
 312                                 continue;
 313                 }
 314                 /*
 315                  * Using the low stale entry.
 316                  * Shift entries up toward the stale slot.
 317                  */
 318                 if (lowstale >= 0 &&
 319                     (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
 320                      index - lowstale - 1 < highstale - index)) {
 321                         ASSERT(INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) ==
 322                                XFS_DIR2_NULL_DATAPTR);
 323                         ASSERT(index - lowstale - 1 >= 0);
 324                         if (index - lowstale - 1 > 0)
 325                                 memmove(&leaf->ents[lowstale],
 326                                         &leaf->ents[lowstale + 1],
 327                                         (index - lowstale - 1) * sizeof(*lep));
 328                         lep = &leaf->ents[index - 1];
 329                         lfloglow = MIN(lowstale, lfloglow);
 330                         lfloghigh = MAX(index - 1, lfloghigh);
 331                 }
 332                 /*
 333                  * Using the high stale entry.
 334                  * Shift entries down toward the stale slot.
 335                  */
 336                 else {
 337                         ASSERT(INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) ==
 338                                XFS_DIR2_NULL_DATAPTR);
 339                         ASSERT(highstale - index >= 0);
 340                         if (highstale - index > 0)
 341                                 memmove(&leaf->ents[index + 1],
 342                                         &leaf->ents[index],
 343                                         (highstale - index) * sizeof(*lep));
 344                         lep = &leaf->ents[index];
 345                         lfloglow = MIN(index, lfloglow);
 346                         lfloghigh = MAX(highstale, lfloghigh);
 347                 }
 348                 INT_MOD(leaf->hdr.stale, ARCH_CONVERT, -1);
 349         }
 350         /*
 351          * Insert the new entry, log everything.
 352          */
 353         INT_SET(lep->hashval, ARCH_CONVERT, args->hashval);
 354         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_DB_OFF_TO_DATAPTR(mp, args->blkno, args->index));
 355         xfs_dir2_leaf_log_header(tp, bp);
 356         xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 357         xfs_dir2_leafn_check(dp, bp);
 358         return 0;
 359 }
 360
 361 #ifdef DEBUG
 362 /*
 363  * Check internal consistency of a leafn block.
 364  */
 365 void
 366 xfs_dir2_leafn_check(
 367         xfs_inode_t     *dp,                    /* incore directory inode */
 368         xfs_dabuf_t     *bp)                    /* leaf buffer */
 369 {
 370         int             i;                      /* leaf index */
 371         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 372         xfs_mount_t     *mp;                    /* filesystem mount point */
 373         int             stale;                  /* count of stale leaves */
 374
 375         leaf = bp->data;
 376         mp = dp->i_mount;
 377         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 378         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) <= XFS_DIR2_MAX_LEAF_ENTS(mp));
 379         for (i = stale = 0; i < INT_GET(leaf->hdr.count, ARCH_CONVERT); i++) {
 380                 if (i + 1 < INT_GET(leaf->hdr.count, ARCH_CONVERT)) {
 381                         ASSERT(INT_GET(leaf->ents[i].hashval, ARCH_CONVERT) <=
 382                                INT_GET(leaf->ents[i + 1].hashval, ARCH_CONVERT));
 383                 }
 384                 if (INT_GET(leaf->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 385                         stale++;
 386         }
 387         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == stale);
 388 }
 389 #endif  /* DEBUG */
 390
 391 /*
 392  * Return the last hash value in the leaf.
 393  * Stale entries are ok.
 394  */
 395 xfs_dahash_t                                    /* hash value */
 396 xfs_dir2_leafn_lasthash(
 397         xfs_dabuf_t     *bp,                    /* leaf buffer */
 398         int             *count)                 /* count of entries in leaf */
 399 {
 400         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 401
 402         leaf = bp->data;
 403         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 404         if (count)
 405                 *count = INT_GET(leaf->hdr.count, ARCH_CONVERT);
 406         if (!leaf->hdr.count)
 407                 return 0;
 408         return INT_GET(leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
 409 }
 410
 411 /*
 412  * Look up a leaf entry in a node-format leaf block.
 413  * If this is an addname then the extrablk in state is a freespace block,
 414  * otherwise it's a data block.
 415  */
 416 int
 417 xfs_dir2_leafn_lookup_int(
 418         xfs_dabuf_t             *bp,            /* leaf buffer */
 419         xfs_da_args_t           *args,          /* operation arguments */
 420         int                     *indexp,        /* out: leaf entry index */
 421         xfs_da_state_t          *state)         /* state to fill in */
 422 {
 423         xfs_dabuf_t             *curbp;         /* current data/free buffer */
 424         xfs_dir2_db_t           curdb;          /* current data block number */
 425         xfs_dir2_db_t           curfdb;         /* current free block number */
 426         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 427         xfs_inode_t             *dp;            /* incore directory inode */
 428         int                     error;          /* error return value */
 429         int                     fi;             /* free entry index */
 430         xfs_dir2_free_t         *free=NULL;     /* free block structure */
 431         int                     index;          /* leaf entry index */
 432         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 433         int                     length=0;       /* length of new data entry */
 434         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 435         xfs_mount_t             *mp;            /* filesystem mount point */
 436         xfs_dir2_db_t           newdb;          /* new data block number */
 437         xfs_dir2_db_t           newfdb;         /* new free block number */
 438         xfs_trans_t             *tp;            /* transaction pointer */
 439
 440         dp = args->dp;
 441         tp = args->trans;
 442         mp = dp->i_mount;
 443         leaf = bp->data;
 444         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 445 #ifdef __KERNEL__
 446         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) > 0);
 447 #endif
 448         xfs_dir2_leafn_check(dp, bp);
 449         /*
 450          * Look up the hash value in the leaf entries.
 451          */
 452         index = xfs_dir2_leaf_search_hash(args, bp);
 453         /*
 454          * Do we have a buffer coming in?
 455          */
 456         if (state->extravalid)
 457                 curbp = state->extrablk.bp;
 458         else
 459                 curbp = NULL;
 460         /*
 461          * For addname, it's a free block buffer, get the block number.
 462          */
 463         if (args->addname) {
 464                 curfdb = curbp ? state->extrablk.blkno : -1;
 465                 curdb = -1;
 466                 length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
 467                 if ((free = (curbp ? curbp->data : NULL)))
 468                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 469         }
 470         /*
 471          * For others, it's a data block buffer, get the block number.
 472          */
 473         else {
 474                 curfdb = -1;
 475                 curdb = curbp ? state->extrablk.blkno : -1;
 476         }
 477         /*
 478          * Loop over leaf entries with the right hash value.
 479          */
 480         for (lep = &leaf->ents[index];
 481              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
 482              lep++, index++) {
 483                 /*
 484                  * Skip stale leaf entries.
 485                  */
 486                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 487                         continue;
 488                 /*
 489                  * Pull the data block number from the entry.
 490                  */
 491                 newdb = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
 492                 /*
 493                  * For addname, we're looking for a place to put the new entry.
 494                  * We want to use a data block with an entry of equal
 495                  * hash value to ours if there is one with room.
 496                  */
 497                 if (args->addname) {
 498                         /*
 499                          * If this block isn't the data block we already have
 500                          * in hand, take a look at it.
 501                          */
 502                         if (newdb != curdb) {
 503                                 curdb = newdb;
 504                                 /*
 505                                  * Convert the data block to the free block
 506                                  * holding its freespace information.
 507                                  */
 508                                 newfdb = XFS_DIR2_DB_TO_FDB(mp, newdb);
 509                                 /*
 510                                  * If it's not the one we have in hand,
 511                                  * read it in.
 512                                  */
 513                                 if (newfdb != curfdb) {
 514                                         /*
 515                                          * If we had one before, drop it.
 516                                          */
 517                                         if (curbp)
 518                                                 xfs_da_brelse(tp, curbp);
 519                                         /*
 520                                          * Read the free block.
 521                                          */
 522                                         if ((error = xfs_da_read_buf(tp, dp,
 523                                                         XFS_DIR2_DB_TO_DA(mp,
 524                                                                 newfdb),
 525                                                         -1, &curbp,
 526                                                         XFS_DATA_FORK))) {
 527                                                 return error;
 528                                         }
 529                                         curfdb = newfdb;
 530                                         free = curbp->data;
 531                                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) ==
 532                                                XFS_DIR2_FREE_MAGIC);
 533                                         ASSERT((INT_GET(free->hdr.firstdb, ARCH_CONVERT) %
 534                                                 XFS_DIR2_MAX_FREE_BESTS(mp)) ==
 535                                                0);
 536                                         ASSERT(INT_GET(free->hdr.firstdb, ARCH_CONVERT) <= curdb);
 537                                         ASSERT(curdb <
 538                                                INT_GET(free->hdr.firstdb, ARCH_CONVERT) +
 539                                                INT_GET(free->hdr.nvalid, ARCH_CONVERT));
 540                                 }
 541                                 /*
 542                                  * Get the index for our entry.
 543                                  */
 544                                 fi = XFS_DIR2_DB_TO_FDINDEX(mp, curdb);
 545                                 /*
 546                                  * If it has room, return it.
 547                                  */
 548                                 if (unlikely(INT_GET(free->bests[fi], ARCH_CONVERT) == NULLDATAOFF)) {
 549                                         XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 550                                                          XFS_ERRLEVEL_LOW, mp);
 551                                         return XFS_ERROR(EFSCORRUPTED);
 552                                 }
 553                                 if (INT_GET(free->bests[fi], ARCH_CONVERT) >= length) {
 554                                         *indexp = index;
 555                                         state->extravalid = 1;
 556                                         state->extrablk.bp = curbp;
 557                                         state->extrablk.blkno = curfdb;
 558                                         state->extrablk.index = fi;
 559                                         state->extrablk.magic =
 560                                                 XFS_DIR2_FREE_MAGIC;
 561                                         ASSERT(args->oknoent);
 562                                         return XFS_ERROR(ENOENT);
 563                                 }
 564                         }
 565                 }
 566                 /*
 567                  * Not adding a new entry, so we really want to find
 568                  * the name given to us.
 569                  */
 570                 else {
 571                         /*
 572                          * If it's a different data block, go get it.
 573                          */
 574                         if (newdb != curdb) {
 575                                 /*
 576                                  * If we had a block before, drop it.
 577                                  */
 578                                 if (curbp)
 579                                         xfs_da_brelse(tp, curbp);
 580                                 /*
 581                                  * Read the data block.
 582                                  */
 583                                 if ((error =
 584                                     xfs_da_read_buf(tp, dp,
 585                                             XFS_DIR2_DB_TO_DA(mp, newdb), -1,
 586                                             &curbp, XFS_DATA_FORK))) {
 587                                         return error;
 588                                 }
 589                                 xfs_dir2_data_check(dp, curbp);
 590                                 curdb = newdb;
 591                         }
 592                         /*
 593                          * Point to the data entry.
 594                          */
 595                         dep = (xfs_dir2_data_entry_t *)
 596                               ((char *)curbp->data +
 597                                XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
 598                         /*
 599                          * Compare the entry, return it if it matches.
 600                          */
 601                         if (dep->namelen == args->namelen &&
 602                             dep->name[0] == args->name[0] &&
 603                             memcmp(dep->name, args->name, args->namelen) == 0) {
 604                                 args->inumber = INT_GET(dep->inumber, ARCH_CONVERT);
 605                                 *indexp = index;
 606                                 state->extravalid = 1;
 607                                 state->extrablk.bp = curbp;
 608                                 state->extrablk.blkno = curdb;
 609                                 state->extrablk.index =
 610                                         (int)((char *)dep -
 611                                               (char *)curbp->data);
 612                                 state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 613                                 return XFS_ERROR(EEXIST);
 614                         }
 615                 }
 616         }
 617         /*
 618          * Didn't find a match.
 619          * If we are holding a buffer, give it back in case our caller
 620          * finds it useful.
 621          */
 622         if ((state->extravalid = (curbp != NULL))) {
 623                 state->extrablk.bp = curbp;
 624                 state->extrablk.index = -1;
 625                 /*
 626                  * For addname, giving back a free block.
 627                  */
 628                 if (args->addname) {
 629                         state->extrablk.blkno = curfdb;
 630                         state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 631                 }
 632                 /*
 633                  * For other callers, giving back a data block.
 634                  */
 635                 else {
 636                         state->extrablk.blkno = curdb;
 637                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 638                 }
 639         }
 640         /*
 641          * Return the final index, that will be the insertion point.
 642          */
 643         *indexp = index;
 644         ASSERT(index == INT_GET(leaf->hdr.count, ARCH_CONVERT) || args->oknoent);
 645         return XFS_ERROR(ENOENT);
 646 }
 647
 648 /*
 649  * Move count leaf entries from source to destination leaf.
 650  * Log entries and headers.  Stale entries are preserved.
 651  */
 652 static void
 653 xfs_dir2_leafn_moveents(
 654         xfs_da_args_t   *args,                  /* operation arguments */
 655         xfs_dabuf_t     *bp_s,                  /* source leaf buffer */
 656         int             start_s,                /* source leaf index */
 657         xfs_dabuf_t     *bp_d,                  /* destination leaf buffer */
 658         int             start_d,                /* destination leaf index */
 659         int             count)                  /* count of leaves to copy */
 660 {
 661         xfs_dir2_leaf_t *leaf_d;                /* destination leaf structure */
 662         xfs_dir2_leaf_t *leaf_s;                /* source leaf structure */
 663         int             stale;                  /* count stale leaves copied */
 664         xfs_trans_t     *tp;                    /* transaction pointer */
 665
 666         xfs_dir2_trace_args_bibii("leafn_moveents", args, bp_s, start_s, bp_d,
 667                 start_d, count);
 668         /*
 669          * Silently return if nothing to do.
 670          */
 671         if (count == 0) {
 672                 return;
 673         }
 674         tp = args->trans;
 675         leaf_s = bp_s->data;
 676         leaf_d = bp_d->data;
 677         /*
 678          * If the destination index is not the end of the current
 679          * destination leaf entries, open up a hole in the destination
 680          * to hold the new entries.
 681          */
 682         if (start_d < INT_GET(leaf_d->hdr.count, ARCH_CONVERT)) {
 683                 memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
 684                         (INT_GET(leaf_d->hdr.count, ARCH_CONVERT) - start_d) *
 685                         sizeof(xfs_dir2_leaf_entry_t));
 686                 xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
 687                         count + INT_GET(leaf_d->hdr.count, ARCH_CONVERT) - 1);
 688         }
 689         /*
 690          * If the source has stale leaves, count the ones in the copy range
 691          * so we can update the header correctly.
 692          */
 693         if (leaf_s->hdr.stale) {
 694                 int     i;                      /* temp leaf index */
 695
 696                 for (i = start_s, stale = 0; i < start_s + count; i++) {
 697                         if (INT_GET(leaf_s->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
 698                                 stale++;
 699                 }
 700         } else
 701                 stale = 0;
 702         /*
 703          * Copy the leaf entries from source to destination.
 704          */
 705         memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
 706                 count * sizeof(xfs_dir2_leaf_entry_t));
 707         xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 708         /*
 709          * If there are source entries after the ones we copied,
 710          * delete the ones we copied by sliding the next ones down.
 711          */
 712         if (start_s + count < INT_GET(leaf_s->hdr.count, ARCH_CONVERT)) {
 713                 memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
 714                         count * sizeof(xfs_dir2_leaf_entry_t));
 715                 xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 716         }
 717         /*
 718          * Update the headers and log them.
 719          */
 720         INT_MOD(leaf_s->hdr.count, ARCH_CONVERT, -(count));
 721         INT_MOD(leaf_s->hdr.stale, ARCH_CONVERT, -(stale));
 722         INT_MOD(leaf_d->hdr.count, ARCH_CONVERT, count);
 723         INT_MOD(leaf_d->hdr.stale, ARCH_CONVERT, stale);
 724         xfs_dir2_leaf_log_header(tp, bp_s);
 725         xfs_dir2_leaf_log_header(tp, bp_d);
 726         xfs_dir2_leafn_check(args->dp, bp_s);
 727         xfs_dir2_leafn_check(args->dp, bp_d);
 728 }
 729
 730 /*
 731  * Determine the sort order of two leaf blocks.
 732  * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 733  */
 734 int                                             /* sort order */
 735 xfs_dir2_leafn_order(
 736         xfs_dabuf_t     *leaf1_bp,              /* leaf1 buffer */
 737         xfs_dabuf_t     *leaf2_bp)              /* leaf2 buffer */
 738 {
 739         xfs_dir2_leaf_t *leaf1;                 /* leaf1 structure */
 740         xfs_dir2_leaf_t *leaf2;                 /* leaf2 structure */
 741
 742         leaf1 = leaf1_bp->data;
 743         leaf2 = leaf2_bp->data;
 744         ASSERT(INT_GET(leaf1->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 745         ASSERT(INT_GET(leaf2->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 746         if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) > 0 &&
 747             INT_GET(leaf2->hdr.count, ARCH_CONVERT) > 0 &&
 748             (INT_GET(leaf2->ents[0].hashval, ARCH_CONVERT) < INT_GET(leaf1->ents[0].hashval, ARCH_CONVERT) ||
 749              INT_GET(leaf2->ents[INT_GET(leaf2->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT) <
 750              INT_GET(leaf1->ents[INT_GET(leaf1->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT)))
 751                 return 1;
 752         return 0;
 753 }
 754
 755 /*
 756  * Rebalance leaf entries between two leaf blocks.
 757  * This is actually only called when the second block is new,
 758  * though the code deals with the general case.
 759  * A new entry will be inserted in one of the blocks, and that
 760  * entry is taken into account when balancing.
 761  */
 762 static void
 763 xfs_dir2_leafn_rebalance(
 764         xfs_da_state_t          *state,         /* btree cursor */
 765         xfs_da_state_blk_t      *blk1,          /* first btree block */
 766         xfs_da_state_blk_t      *blk2)          /* second btree block */
 767 {
 768         xfs_da_args_t           *args;          /* operation arguments */
 769         int                     count;          /* count (& direction) leaves */
 770         int                     isleft;         /* new goes in left leaf */
 771         xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 772         xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
 773         int                     mid;            /* midpoint leaf index */
 774 #ifdef DEBUG
 775         int                     oldstale;       /* old count of stale leaves */
 776 #endif
 777         int                     oldsum;         /* old total leaf count */
 778         int                     swap;           /* swapped leaf blocks */
 779
 780         args = state->args;
 781         /*
 782          * If the block order is wrong, swap the arguments.
 783          */
 784         if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
 785                 xfs_da_state_blk_t      *tmp;   /* temp for block swap */
 786
 787                 tmp = blk1;
 788                 blk1 = blk2;
 789                 blk2 = tmp;
 790         }
 791         leaf1 = blk1->bp->data;
 792         leaf2 = blk2->bp->data;
 793         oldsum = INT_GET(leaf1->hdr.count, ARCH_CONVERT) + INT_GET(leaf2->hdr.count, ARCH_CONVERT);
 794 #ifdef DEBUG
 795         oldstale = INT_GET(leaf1->hdr.stale, ARCH_CONVERT) + INT_GET(leaf2->hdr.stale, ARCH_CONVERT);
 796 #endif
 797         mid = oldsum >> 1;
 798         /*
 799          * If the old leaf count was odd then the new one will be even,
 800          * so we need to divide the new count evenly.
 801          */
 802         if (oldsum & 1) {
 803                 xfs_dahash_t    midhash;        /* middle entry hash value */
 804
 805                 if (mid >= INT_GET(leaf1->hdr.count, ARCH_CONVERT))
 806                         midhash = INT_GET(leaf2->ents[mid - INT_GET(leaf1->hdr.count, ARCH_CONVERT)].hashval, ARCH_CONVERT);
 807                 else
 808                         midhash = INT_GET(leaf1->ents[mid].hashval, ARCH_CONVERT);
 809                 isleft = args->hashval <= midhash;
 810         }
 811         /*
 812          * If the old count is even then the new count is odd, so there's
 813          * no preferred side for the new entry.
 814          * Pick the left one.
 815          */
 816         else
 817                 isleft = 1;
 818         /*
 819          * Calculate moved entry count.  Positive means left-to-right,
 820          * negative means right-to-left.  Then move the entries.
 821          */
 822         count = INT_GET(leaf1->hdr.count, ARCH_CONVERT) - mid + (isleft == 0);
 823         if (count > 0)
 824                 xfs_dir2_leafn_moveents(args, blk1->bp,
 825                         INT_GET(leaf1->hdr.count, ARCH_CONVERT) - count, blk2->bp, 0, count);
 826         else if (count < 0)
 827                 xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
 828                         INT_GET(leaf1->hdr.count, ARCH_CONVERT), count);
 829         ASSERT(INT_GET(leaf1->hdr.count, ARCH_CONVERT) + INT_GET(leaf2->hdr.count, ARCH_CONVERT) == oldsum);
 830         ASSERT(INT_GET(leaf1->hdr.stale, ARCH_CONVERT) + INT_GET(leaf2->hdr.stale, ARCH_CONVERT) == oldstale);
 831         /*
 832          * Mark whether we're inserting into the old or new leaf.
 833          */
 834         if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) < INT_GET(leaf2->hdr.count, ARCH_CONVERT))
 835                 state->inleaf = swap;
 836         else if (INT_GET(leaf1->hdr.count, ARCH_CONVERT) > INT_GET(leaf2->hdr.count, ARCH_CONVERT))
 837                 state->inleaf = !swap;
 838         else
 839                 state->inleaf =
 840                         swap ^ (blk1->index <= INT_GET(leaf1->hdr.count, ARCH_CONVERT));
 841         /*
 842          * Adjust the expected index for insertion.
 843          */
 844         if (!state->inleaf)
 845                 blk2->index = blk1->index - INT_GET(leaf1->hdr.count, ARCH_CONVERT);
 846
 847         /*
 848          * Finally sanity check just to make sure we are not returning a negative index
 849          */
 850         if(blk2->index < 0) {
 851                 state->inleaf = 1;
 852                 blk2->index = 0;
 853                 cmn_err(CE_ALERT,
 854                         "xfs_dir2_leafn_rebalance: picked the wrong leaf? reverting orignal leaf: "
 855                         "blk1->index %d\n",
 856                         blk1->index);
 857         }
 858 }
 859
 860 /*
 861  * Remove an entry from a node directory.
 862  * This removes the leaf entry and the data entry,
 863  * and updates the free block if necessary.
 864  */
 865 static int                                      /* error */
 866 xfs_dir2_leafn_remove(
 867         xfs_da_args_t           *args,          /* operation arguments */
 868         xfs_dabuf_t             *bp,            /* leaf buffer */
 869         int                     index,          /* leaf entry index */
 870         xfs_da_state_blk_t      *dblk,          /* data block */
 871         int                     *rval)          /* resulting block needs join */
 872 {
 873         xfs_dir2_data_t         *data;          /* data block structure */
 874         xfs_dir2_db_t           db;             /* data block number */
 875         xfs_dabuf_t             *dbp;           /* data block buffer */
 876         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 877         xfs_inode_t             *dp;            /* incore directory inode */
 878         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 879         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 880         int                     longest;        /* longest data free entry */
 881         int                     off;            /* data block entry offset */
 882         xfs_mount_t             *mp;            /* filesystem mount point */
 883         int                     needlog;        /* need to log data header */
 884         int                     needscan;       /* need to rescan data frees */
 885         xfs_trans_t             *tp;            /* transaction pointer */
 886
 887         xfs_dir2_trace_args_sb("leafn_remove", args, index, bp);
 888         dp = args->dp;
 889         tp = args->trans;
 890         mp = dp->i_mount;
 891         leaf = bp->data;
 892         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
 893         /*
 894          * Point to the entry we're removing.
 895          */
 896         lep = &leaf->ents[index];
 897         /*
 898          * Extract the data block and offset from the entry.
 899          */
 900         db = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
 901         ASSERT(dblk->blkno == db);
 902         off = XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT));
 903         ASSERT(dblk->index == off);
 904         /*
 905          * Kill the leaf entry by marking it stale.
 906          * Log the leaf block changes.
 907          */
 908         INT_MOD(leaf->hdr.stale, ARCH_CONVERT, +1);
 909         xfs_dir2_leaf_log_header(tp, bp);
 910         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_NULL_DATAPTR);
 911         xfs_dir2_leaf_log_ents(tp, bp, index, index);
 912         /*
 913          * Make the data entry free.  Keep track of the longest freespace
 914          * in the data block in case it changes.
 915          */
 916         dbp = dblk->bp;
 917         data = dbp->data;
 918         dep = (xfs_dir2_data_entry_t *)((char *)data + off);
 919         longest = INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT);
 920         needlog = needscan = 0;
 921         xfs_dir2_data_make_free(tp, dbp, off,
 922                 XFS_DIR2_DATA_ENTSIZE(dep->namelen), &needlog, &needscan);
 923         /*
 924          * Rescan the data block freespaces for bestfree.
 925          * Log the data block header if needed.
 926          */
 927         if (needscan)
 928                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
 929         if (needlog)
 930                 xfs_dir2_data_log_header(tp, dbp);
 931         xfs_dir2_data_check(dp, dbp);
 932         /*
 933          * If the longest data block freespace changes, need to update
 934          * the corresponding freeblock entry.
 935          */
 936         if (longest < INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT)) {
 937                 int             error;          /* error return value */
 938                 xfs_dabuf_t     *fbp;           /* freeblock buffer */
 939                 xfs_dir2_db_t   fdb;            /* freeblock block number */
 940                 int             findex;         /* index in freeblock entries */
 941                 xfs_dir2_free_t *free;          /* freeblock structure */
 942                 int             logfree;        /* need to log free entry */
 943
 944                 /*
 945                  * Convert the data block number to a free block,
 946                  * read in the free block.
 947                  */
 948                 fdb = XFS_DIR2_DB_TO_FDB(mp, db);
 949                 if ((error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb),
 950                                 -1, &fbp, XFS_DATA_FORK))) {
 951                         return error;
 952                 }
 953                 free = fbp->data;
 954                 ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
 955                 ASSERT(INT_GET(free->hdr.firstdb, ARCH_CONVERT) ==
 956                        XFS_DIR2_MAX_FREE_BESTS(mp) *
 957                        (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
 958                 /*
 959                  * Calculate which entry we need to fix.
 960                  */
 961                 findex = XFS_DIR2_DB_TO_FDINDEX(mp, db);
 962                 longest = INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT);
 963                 /*
 964                  * If the data block is now empty we can get rid of it
 965                  * (usually).
 966                  */
 967                 if (longest == mp->m_dirblksize - (uint)sizeof(data->hdr)) {
 968                         /*
 969                          * Try to punch out the data block.
 970                          */
 971                         error = xfs_dir2_shrink_inode(args, db, dbp);
 972                         if (error == 0) {
 973                                 dblk->bp = NULL;
 974                                 data = NULL;
 975                         }
 976                         /*
 977                          * We can get ENOSPC if there's no space reservation.
 978                          * In this case just drop the buffer and some one else
 979                          * will eventually get rid of the empty block.
 980                          */
 981                         else if (error == ENOSPC && args->total == 0)
 982                                 xfs_da_buf_done(dbp);
 983                         else
 984                                 return error;
 985                 }
 986                 /*
 987                  * If we got rid of the data block, we can eliminate that entry
 988                  * in the free block.
 989                  */
 990                 if (data == NULL) {
 991                         /*
 992                          * One less used entry in the free table.
 993                          */
 994                         INT_MOD(free->hdr.nused, ARCH_CONVERT, -1);
 995                         xfs_dir2_free_log_header(tp, fbp);
 996                         /*
 997                          * If this was the last entry in the table, we can
 998                          * trim the table size back.  There might be other
 999                          * entries at the end referring to non-existent
1000                          * data blocks, get those too.
1001                          */
1002                         if (findex == INT_GET(free->hdr.nvalid, ARCH_CONVERT) - 1) {
1003                                 int     i;              /* free entry index */
1004
1005                                 for (i = findex - 1;
1006                                      i >= 0 && INT_GET(free->bests[i], ARCH_CONVERT) == NULLDATAOFF;
1007                                      i--)
1008                                         continue;
1009                                 INT_SET(free->hdr.nvalid, ARCH_CONVERT, i + 1);
1010                                 logfree = 0;
1011                         }
1012                         /*
1013                          * Not the last entry, just punch it out.
1014                          */
1015                         else {
1016                                 INT_SET(free->bests[findex], ARCH_CONVERT, NULLDATAOFF);
1017                                 logfree = 1;
1018                         }
1019                         /*
1020                          * If there are no useful entries left in the block,
1021                          * get rid of the block if we can.
1022                          */
1023                         if (!free->hdr.nused) {
1024                                 error = xfs_dir2_shrink_inode(args, fdb, fbp);
1025                                 if (error == 0) {
1026                                         fbp = NULL;
1027                                         logfree = 0;
1028                                 } else if (error != ENOSPC || args->total != 0)
1029                                         return error;
1030                                 /*
1031                                  * It's possible to get ENOSPC if there is no
1032                                  * space reservation.  In this case some one
1033                                  * else will eventually get rid of this block.
1034                                  */
1035                         }
1036                 }
1037                 /*
1038                  * Data block is not empty, just set the free entry to
1039                  * the new value.
1040                  */
1041                 else {
1042                         INT_SET(free->bests[findex], ARCH_CONVERT, longest);
1043                         logfree = 1;
1044                 }
1045                 /*
1046                  * Log the free entry that changed, unless we got rid of it.
1047                  */
1048                 if (logfree)
1049                         xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1050                 /*
1051                  * Drop the buffer if we still have it.
1052                  */
1053                 if (fbp)
1054                         xfs_da_buf_done(fbp);
1055         }
1056         xfs_dir2_leafn_check(dp, bp);
1057         /*
1058          * Return indication of whether this leaf block is emtpy enough
1059          * to justify trying to join it with a neighbor.
1060          */
1061         *rval =
1062                 ((uint)sizeof(leaf->hdr) +
1063                  (uint)sizeof(leaf->ents[0]) *
1064                  (INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT))) <
1065                 mp->m_dir_magicpct;
1066         return 0;
1067 }
1068
1069 /*
1070  * Split the leaf entries in the old block into old and new blocks.
1071  */
1072 int                                             /* error */
1073 xfs_dir2_leafn_split(
1074         xfs_da_state_t          *state,         /* btree cursor */
1075         xfs_da_state_blk_t      *oldblk,        /* original block */
1076         xfs_da_state_blk_t      *newblk)        /* newly created block */
1077 {
1078         xfs_da_args_t           *args;          /* operation arguments */
1079         xfs_dablk_t             blkno;          /* new leaf block number */
1080         int                     error;          /* error return value */
1081         xfs_mount_t             *mp;            /* filesystem mount point */
1082
1083         /*
1084          * Allocate space for a new leaf node.
1085          */
1086         args = state->args;
1087         mp = args->dp->i_mount;
1088         ASSERT(args != NULL);
1089         ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1090         error = xfs_da_grow_inode(args, &blkno);
1091         if (error) {
1092                 return error;
1093         }
1094         /*
1095          * Initialize the new leaf block.
1096          */
1097         error = xfs_dir2_leaf_init(args, XFS_DIR2_DA_TO_DB(mp, blkno),
1098                 &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1099         if (error) {
1100                 return error;
1101         }
1102         newblk->blkno = blkno;
1103         newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1104         /*
1105          * Rebalance the entries across the two leaves, link the new
1106          * block into the leaves.
1107          */
1108         xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1109         error = xfs_da_blk_link(state, oldblk, newblk);
1110         if (error) {
1111                 return error;
1112         }
1113         /*
1114          * Insert the new entry in the correct block.
1115          */
1116         if (state->inleaf)
1117                 error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1118         else
1119                 error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1120         /*
1121          * Update last hashval in each block since we added the name.
1122          */
1123         oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1124         newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1125         xfs_dir2_leafn_check(args->dp, oldblk->bp);
1126         xfs_dir2_leafn_check(args->dp, newblk->bp);
1127         return error;
1128 }
1129
1130 /*
1131  * Check a leaf block and its neighbors to see if the block should be
1132  * collapsed into one or the other neighbor.  Always keep the block
1133  * with the smaller block number.
1134  * If the current block is over 50% full, don't try to join it, return 0.
1135  * If the block is empty, fill in the state structure and return 2.
1136  * If it can be collapsed, fill in the state structure and return 1.
1137  * If nothing can be done, return 0.
1138  */
1139 int                                             /* error */
1140 xfs_dir2_leafn_toosmall(
1141         xfs_da_state_t          *state,         /* btree cursor */
1142         int                     *action)        /* resulting action to take */
1143 {
1144         xfs_da_state_blk_t      *blk;           /* leaf block */
1145         xfs_dablk_t             blkno;          /* leaf block number */
1146         xfs_dabuf_t             *bp;            /* leaf buffer */
1147         int                     bytes;          /* bytes in use */
1148         int                     count;          /* leaf live entry count */
1149         int                     error;          /* error return value */
1150         int                     forward;        /* sibling block direction */
1151         int                     i;              /* sibling counter */
1152         xfs_da_blkinfo_t        *info;          /* leaf block header */
1153         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1154         int                     rval;           /* result from path_shift */
1155
1156         /*
1157          * Check for the degenerate case of the block being over 50% full.
1158          * If so, it's not worth even looking to see if we might be able
1159          * to coalesce with a sibling.
1160          */
1161         blk = &state->path.blk[state->path.active - 1];
1162         info = blk->bp->data;
1163         ASSERT(INT_GET(info->magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1164         leaf = (xfs_dir2_leaf_t *)info;
1165         count = INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1166         bytes = (uint)sizeof(leaf->hdr) + count * (uint)sizeof(leaf->ents[0]);
1167         if (bytes > (state->blocksize >> 1)) {
1168                 /*
1169                  * Blk over 50%, don't try to join.
1170                  */
1171                 *action = 0;
1172                 return 0;
1173         }
1174         /*
1175          * Check for the degenerate case of the block being empty.
1176          * If the block is empty, we'll simply delete it, no need to
1177          * coalesce it with a sibling block.  We choose (arbitrarily)
1178          * to merge with the forward block unless it is NULL.
1179          */
1180         if (count == 0) {
1181                 /*
1182                  * Make altpath point to the block we want to keep and
1183                  * path point to the block we want to drop (this one).
1184                  */
1185                 forward = info->forw;
1186                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1187                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1188                         &rval);
1189                 if (error)
1190                         return error;
1191                 *action = rval ? 2 : 0;
1192                 return 0;
1193         }
1194         /*
1195          * Examine each sibling block to see if we can coalesce with
1196          * at least 25% free space to spare.  We need to figure out
1197          * whether to merge with the forward or the backward block.
1198          * We prefer coalescing with the lower numbered sibling so as
1199          * to shrink a directory over time.
1200          */
1201         forward = INT_GET(info->forw, ARCH_CONVERT) < INT_GET(info->back, ARCH_CONVERT);
1202         for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1203                 blkno = forward ?INT_GET( info->forw, ARCH_CONVERT) : INT_GET(info->back, ARCH_CONVERT);
1204                 if (blkno == 0)
1205                         continue;
1206                 /*
1207                  * Read the sibling leaf block.
1208                  */
1209                 if ((error =
1210                     xfs_da_read_buf(state->args->trans, state->args->dp, blkno,
1211                             -1, &bp, XFS_DATA_FORK))) {
1212                         return error;
1213                 }
1214                 ASSERT(bp != NULL);
1215                 /*
1216                  * Count bytes in the two blocks combined.
1217                  */
1218                 leaf = (xfs_dir2_leaf_t *)info;
1219                 count = INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1220                 bytes = state->blocksize - (state->blocksize >> 2);
1221                 leaf = bp->data;
1222                 ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1223                 count += INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT);
1224                 bytes -= count * (uint)sizeof(leaf->ents[0]);
1225                 /*
1226                  * Fits with at least 25% to spare.
1227                  */
1228                 if (bytes >= 0)
1229                         break;
1230                 xfs_da_brelse(state->args->trans, bp);
1231         }
1232         /*
1233          * Didn't like either block, give up.
1234          */
1235         if (i >= 2) {
1236                 *action = 0;
1237                 return 0;
1238         }
1239         /*
1240          * Done with the sibling leaf block here, drop the dabuf
1241          * so path_shift can get it.
1242          */
1243         xfs_da_buf_done(bp);
1244         /*
1245          * Make altpath point to the block we want to keep (the lower
1246          * numbered block) and path point to the block we want to drop.
1247          */
1248         memcpy(&state->altpath, &state->path, sizeof(state->path));
1249         if (blkno < blk->blkno)
1250                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1251                         &rval);
1252         else
1253                 error = xfs_da_path_shift(state, &state->path, forward, 0,
1254                         &rval);
1255         if (error) {
1256                 return error;
1257         }
1258         *action = rval ? 0 : 1;
1259         return 0;
1260 }
1261
1262 /*
1263  * Move all the leaf entries from drop_blk to save_blk.
1264  * This is done as part of a join operation.
1265  */
1266 void
1267 xfs_dir2_leafn_unbalance(
1268         xfs_da_state_t          *state,         /* cursor */
1269         xfs_da_state_blk_t      *drop_blk,      /* dead block */
1270         xfs_da_state_blk_t      *save_blk)      /* surviving block */
1271 {
1272         xfs_da_args_t           *args;          /* operation arguments */
1273         xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1274         xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1275
1276         args = state->args;
1277         ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1278         ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1279         drop_leaf = drop_blk->bp->data;
1280         save_leaf = save_blk->bp->data;
1281         ASSERT(INT_GET(drop_leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1282         ASSERT(INT_GET(save_leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1283         /*
1284          * If there are any stale leaf entries, take this opportunity
1285          * to purge them.
1286          */
1287         if (INT_GET(drop_leaf->hdr.stale, ARCH_CONVERT))
1288                 xfs_dir2_leaf_compact(args, drop_blk->bp);
1289         if (INT_GET(save_leaf->hdr.stale, ARCH_CONVERT))
1290                 xfs_dir2_leaf_compact(args, save_blk->bp);
1291         /*
1292          * Move the entries from drop to the appropriate end of save.
1293          */
1294         drop_blk->hashval = INT_GET(drop_leaf->ents[INT_GET(drop_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1295         if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1296                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp, 0,
1297                         INT_GET(drop_leaf->hdr.count, ARCH_CONVERT));
1298         else
1299                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp,
1300                         INT_GET(save_leaf->hdr.count, ARCH_CONVERT), INT_GET(drop_leaf->hdr.count, ARCH_CONVERT));
1301         save_blk->hashval = INT_GET(save_leaf->ents[INT_GET(save_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
1302         xfs_dir2_leafn_check(args->dp, save_blk->bp);
1303 }
1304
1305 /*
1306  * Top-level node form directory addname routine.
1307  */
1308 int                                             /* error */
1309 xfs_dir2_node_addname(
1310         xfs_da_args_t           *args)          /* operation arguments */
1311 {
1312         xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1313         int                     error;          /* error return value */
1314         int                     rval;           /* sub-return value */
1315         xfs_da_state_t          *state;         /* btree cursor */
1316
1317         xfs_dir2_trace_args("node_addname", args);
1318         /*
1319          * Allocate and initialize the state (btree cursor).
1320          */
1321         state = xfs_da_state_alloc();
1322         state->args = args;
1323         state->mp = args->dp->i_mount;
1324         state->blocksize = state->mp->m_dirblksize;
1325         state->node_ents = state->mp->m_dir_node_ents;
1326         /*
1327          * Look up the name.  We're not supposed to find it, but
1328          * this gives us the insertion point.
1329          */
1330         error = xfs_da_node_lookup_int(state, &rval);
1331         if (error)
1332                 rval = error;
1333         if (rval != ENOENT) {
1334                 goto done;
1335         }
1336         /*
1337          * Add the data entry to a data block.
1338          * Extravalid is set to a freeblock found by lookup.
1339          */
1340         rval = xfs_dir2_node_addname_int(args,
1341                 state->extravalid ? &state->extrablk : NULL);
1342         if (rval) {
1343                 goto done;
1344         }
1345         blk = &state->path.blk[state->path.active - 1];
1346         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1347         /*
1348          * Add the new leaf entry.
1349          */
1350         rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1351         if (rval == 0) {
1352                 /*
1353                  * It worked, fix the hash values up the btree.
1354                  */
1355                 if (!args->justcheck)
1356                         xfs_da_fixhashpath(state, &state->path);
1357         } else {
1358                 /*
1359                  * It didn't work, we need to split the leaf block.
1360                  */
1361                 if (args->total == 0) {
1362                         ASSERT(rval == ENOSPC);
1363                         goto done;
1364                 }
1365                 /*
1366                  * Split the leaf block and insert the new entry.
1367                  */
1368                 rval = xfs_da_split(state);
1369         }
1370 done:
1371         xfs_da_state_free(state);
1372         return rval;
1373 }
1374
1375 /*
1376  * Add the data entry for a node-format directory name addition.
1377  * The leaf entry is added in xfs_dir2_leafn_add.
1378  * We may enter with a freespace block that the lookup found.
1379  */
1380 static int                                      /* error */
1381 xfs_dir2_node_addname_int(
1382         xfs_da_args_t           *args,          /* operation arguments */
1383         xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1384 {
1385         xfs_dir2_data_t         *data;          /* data block structure */
1386         xfs_dir2_db_t           dbno;           /* data block number */
1387         xfs_dabuf_t             *dbp;           /* data block buffer */
1388         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1389         xfs_inode_t             *dp;            /* incore directory inode */
1390         xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1391         int                     error;          /* error return value */
1392         xfs_dir2_db_t           fbno;           /* freespace block number */
1393         xfs_dabuf_t             *fbp;           /* freespace buffer */
1394         int                     findex;         /* freespace entry index */
1395         xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1396         xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1397         xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1398         int                     length;         /* length of the new entry */
1399         int                     logfree;        /* need to log free entry */
1400         xfs_mount_t             *mp;            /* filesystem mount point */
1401         int                     needlog;        /* need to log data header */
1402         int                     needscan;       /* need to rescan data frees */
1403         xfs_dir2_data_off_t     *tagp;          /* data entry tag pointer */
1404         xfs_trans_t             *tp;            /* transaction pointer */
1405
1406         dp = args->dp;
1407         mp = dp->i_mount;
1408         tp = args->trans;
1409         length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
1410         /*
1411          * If we came in with a freespace block that means that lookup
1412          * found an entry with our hash value.  This is the freespace
1413          * block for that data entry.
1414          */
1415         if (fblk) {
1416                 fbp = fblk->bp;
1417                 /*
1418                  * Remember initial freespace block number.
1419                  */
1420                 ifbno = fblk->blkno;
1421                 free = fbp->data;
1422                 ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1423                 findex = fblk->index;
1424                 /*
1425                  * This means the free entry showed that the data block had
1426                  * space for our entry, so we remembered it.
1427                  * Use that data block.
1428                  */
1429                 if (findex >= 0) {
1430                         ASSERT(findex < INT_GET(free->hdr.nvalid, ARCH_CONVERT));
1431                         ASSERT(INT_GET(free->bests[findex], ARCH_CONVERT) != NULLDATAOFF);
1432                         ASSERT(INT_GET(free->bests[findex], ARCH_CONVERT) >= length);
1433                         dbno = INT_GET(free->hdr.firstdb, ARCH_CONVERT) + findex;
1434                 }
1435                 /*
1436                  * The data block looked at didn't have enough room.
1437                  * We'll start at the beginning of the freespace entries.
1438                  */
1439                 else {
1440                         dbno = -1;
1441                         findex = 0;
1442                 }
1443         }
1444         /*
1445          * Didn't come in with a freespace block, so don't have a data block.
1446          */
1447         else {
1448                 ifbno = dbno = -1;
1449                 fbp = NULL;
1450                 findex = 0;
1451         }
1452         /*
1453          * If we don't have a data block yet, we're going to scan the
1454          * freespace blocks looking for one.  Figure out what the
1455          * highest freespace block number is.
1456          */
1457         if (dbno == -1) {
1458                 xfs_fileoff_t   fo;             /* freespace block number */
1459
1460                 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1461                         return error;
1462                 lastfbno = XFS_DIR2_DA_TO_DB(mp, (xfs_dablk_t)fo);
1463                 fbno = ifbno;
1464         }
1465         /*
1466          * While we haven't identified a data block, search the freeblock
1467          * data for a good data block.  If we find a null freeblock entry,
1468          * indicating a hole in the data blocks, remember that.
1469          */
1470         while (dbno == -1) {
1471                 /*
1472                  * If we don't have a freeblock in hand, get the next one.
1473                  */
1474                 if (fbp == NULL) {
1475                         /*
1476                          * Happens the first time through unless lookup gave
1477                          * us a freespace block to start with.
1478                          */
1479                         if (++fbno == 0)
1480                                 fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1481                         /*
1482                          * If it's ifbno we already looked at it.
1483                          */
1484                         if (fbno == ifbno)
1485                                 fbno++;
1486                         /*
1487                          * If it's off the end we're done.
1488                          */
1489                         if (fbno >= lastfbno)
1490                                 break;
1491                         /*
1492                          * Read the block.  There can be holes in the
1493                          * freespace blocks, so this might not succeed.
1494                          * This should be really rare, so there's no reason
1495                          * to avoid it.
1496                          */
1497                         if ((error = xfs_da_read_buf(tp, dp,
1498                                         XFS_DIR2_DB_TO_DA(mp, fbno), -2, &fbp,
1499                                         XFS_DATA_FORK))) {
1500                                 return error;
1501                         }
1502                         if (unlikely(fbp == NULL)) {
1503                                 continue;
1504                         }
1505                         free = fbp->data;
1506                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1507                         findex = 0;
1508                 }
1509                 /*
1510                  * Look at the current free entry.  Is it good enough?
1511                  */
1512                 if (INT_GET(free->bests[findex], ARCH_CONVERT) != NULLDATAOFF &&
1513                     INT_GET(free->bests[findex], ARCH_CONVERT) >= length)
1514                         dbno = INT_GET(free->hdr.firstdb, ARCH_CONVERT) + findex;
1515                 else {
1516                         /*
1517                          * Are we done with the freeblock?
1518                          */
1519                         if (++findex == INT_GET(free->hdr.nvalid, ARCH_CONVERT)) {
1520                                 /*
1521                                  * Drop the block.
1522                                  */
1523                                 xfs_da_brelse(tp, fbp);
1524                                 fbp = NULL;
1525                                 if (fblk && fblk->bp)
1526                                         fblk->bp = NULL;
1527                         }
1528                 }
1529         }
1530         /*
1531          * If we don't have a data block, we need to allocate one and make
1532          * the freespace entries refer to it.
1533          */
1534         if (unlikely(dbno == -1)) {
1535                 /*
1536                  * Not allowed to allocate, return failure.
1537                  */
1538                 if (args->justcheck || args->total == 0) {
1539                         /*
1540                          * Drop the freespace buffer unless it came from our
1541                          * caller.
1542                          */
1543                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1544                                 xfs_da_buf_done(fbp);
1545                         return XFS_ERROR(ENOSPC);
1546                 }
1547                 /*
1548                  * Allocate and initialize the new data block.
1549                  */
1550                 if (unlikely((error = xfs_dir2_grow_inode(args,
1551                                                          XFS_DIR2_DATA_SPACE,
1552                                                          &dbno)) ||
1553                     (error = xfs_dir2_data_init(args, dbno, &dbp)))) {
1554                         /*
1555                          * Drop the freespace buffer unless it came from our
1556                          * caller.
1557                          */
1558                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1559                                 xfs_da_buf_done(fbp);
1560                         return error;
1561                 }
1562                 /*
1563                  * If (somehow) we have a freespace block, get rid of it.
1564                  */
1565                 if (fbp)
1566                         xfs_da_brelse(tp, fbp);
1567                 if (fblk && fblk->bp)
1568                         fblk->bp = NULL;
1569
1570                 /*
1571                  * Get the freespace block corresponding to the data block
1572                  * that was just allocated.
1573                  */
1574                 fbno = XFS_DIR2_DB_TO_FDB(mp, dbno);
1575                 if (unlikely(error = xfs_da_read_buf(tp, dp,
1576                                 XFS_DIR2_DB_TO_DA(mp, fbno), -2, &fbp,
1577                                 XFS_DATA_FORK))) {
1578                         xfs_da_buf_done(dbp);
1579                         return error;
1580                 }
1581                 /*
1582                  * If there wasn't a freespace block, the read will
1583                  * return a NULL fbp.  Allocate and initialize a new one.
1584                  */
1585                 if( fbp == NULL ) {
1586                         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1587                                                         &fbno))) {
1588                                 return error;
1589                         }
1590
1591                         if (unlikely(XFS_DIR2_DB_TO_FDB(mp, dbno) != fbno)) {
1592                                 cmn_err(CE_ALERT,
1593                                         "xfs_dir2_node_addname_int: dir ino "
1594                                         "%llu needed freesp block %lld for\n"
1595                                         "  data block %lld, got %lld\n"
1596                                         "  ifbno %llu lastfbno %d\n",
1597                                         (unsigned long long)dp->i_ino,
1598                                         (long long)XFS_DIR2_DB_TO_FDB(mp, dbno),
1599                                         (long long)dbno, (long long)fbno,
1600                                         (unsigned long long)ifbno, lastfbno);
1601                                 if (fblk) {
1602                                         cmn_err(CE_ALERT,
1603                                                 " fblk 0x%p blkno %llu "
1604                                                 "index %d magic 0x%x\n",
1605                                                 fblk,
1606                                                 (unsigned long long)fblk->blkno,
1607                                                 fblk->index,
1608                                                 fblk->magic);
1609                                 } else {
1610                                         cmn_err(CE_ALERT,
1611                                                 " ... fblk is NULL\n");
1612                                 }
1613                                 XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1614                                                  XFS_ERRLEVEL_LOW, mp);
1615                                 return XFS_ERROR(EFSCORRUPTED);
1616                         }
1617
1618                         /*
1619                          * Get a buffer for the new block.
1620                          */
1621                         if ((error = xfs_da_get_buf(tp, dp,
1622                                                    XFS_DIR2_DB_TO_DA(mp, fbno),
1623                                                    -1, &fbp, XFS_DATA_FORK))) {
1624                                 return error;
1625                         }
1626                         ASSERT(fbp != NULL);
1627
1628                         /*
1629                          * Initialize the new block to be empty, and remember
1630                          * its first slot as our empty slot.
1631                          */
1632                         free = fbp->data;
1633                         INT_SET(free->hdr.magic, ARCH_CONVERT, XFS_DIR2_FREE_MAGIC);
1634                         INT_SET(free->hdr.firstdb, ARCH_CONVERT,
1635                                 (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1636                                 XFS_DIR2_MAX_FREE_BESTS(mp));
1637                         free->hdr.nvalid = 0;
1638                         free->hdr.nused = 0;
1639                 } else {
1640                         free = fbp->data;
1641                         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1642                 }
1643
1644                 /*
1645                  * Set the freespace block index from the data block number.
1646                  */
1647                 findex = XFS_DIR2_DB_TO_FDINDEX(mp, dbno);
1648                 /*
1649                  * If it's after the end of the current entries in the
1650                  * freespace block, extend that table.
1651                  */
1652                 if (findex >= INT_GET(free->hdr.nvalid, ARCH_CONVERT)) {
1653                         ASSERT(findex < XFS_DIR2_MAX_FREE_BESTS(mp));
1654                         INT_SET(free->hdr.nvalid, ARCH_CONVERT, findex + 1);
1655                         /*
1656                          * Tag new entry so nused will go up.
1657                          */
1658                         INT_SET(free->bests[findex], ARCH_CONVERT, NULLDATAOFF);
1659                 }
1660                 /*
1661                  * If this entry was for an empty data block
1662                  * (this should always be true) then update the header.
1663                  */
1664                 if (INT_GET(free->bests[findex], ARCH_CONVERT) == NULLDATAOFF) {
1665                         INT_MOD(free->hdr.nused, ARCH_CONVERT, +1);
1666                         xfs_dir2_free_log_header(tp, fbp);
1667                 }
1668                 /*
1669                  * Update the real value in the table.
1670                  * We haven't allocated the data entry yet so this will
1671                  * change again.
1672                  */
1673                 data = dbp->data;
1674                 INT_COPY(free->bests[findex], data->hdr.bestfree[0].length, ARCH_CONVERT);
1675                 logfree = 1;
1676         }
1677         /*
1678          * We had a data block so we don't have to make a new one.
1679          */
1680         else {
1681                 /*
1682                  * If just checking, we succeeded.
1683                  */
1684                 if (args->justcheck) {
1685                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1686                                 xfs_da_buf_done(fbp);
1687                         return 0;
1688                 }
1689                 /*
1690                  * Read the data block in.
1691                  */
1692                 if (unlikely(
1693                     error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, dbno),
1694                                 -1, &dbp, XFS_DATA_FORK))) {
1695                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1696                                 xfs_da_buf_done(fbp);
1697                         return error;
1698                 }
1699                 data = dbp->data;
1700                 logfree = 0;
1701         }
1702         ASSERT(INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT) >= length);
1703         /*
1704          * Point to the existing unused space.
1705          */
1706         dup = (xfs_dir2_data_unused_t *)
1707               ((char *)data + INT_GET(data->hdr.bestfree[0].offset, ARCH_CONVERT));
1708         needscan = needlog = 0;
1709         /*
1710          * Mark the first part of the unused space, inuse for us.
1711          */
1712         xfs_dir2_data_use_free(tp, dbp, dup,
1713                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)data), length,
1714                 &needlog, &needscan);
1715         /*
1716          * Fill in the new entry and log it.
1717          */
1718         dep = (xfs_dir2_data_entry_t *)dup;
1719         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
1720         dep->namelen = args->namelen;
1721         memcpy(dep->name, args->name, dep->namelen);
1722         tagp = XFS_DIR2_DATA_ENTRY_TAG_P(dep);
1723         INT_SET(*tagp, ARCH_CONVERT, (xfs_dir2_data_off_t)((char *)dep - (char *)data));
1724         xfs_dir2_data_log_entry(tp, dbp, dep);
1725         /*
1726          * Rescan the block for bestfree if needed.
1727          */
1728         if (needscan)
1729                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
1730         /*
1731          * Log the data block header if needed.
1732          */
1733         if (needlog)
1734                 xfs_dir2_data_log_header(tp, dbp);
1735         /*
1736          * If the freespace entry is now wrong, update it.
1737          */
1738         if (INT_GET(free->bests[findex], ARCH_CONVERT) != INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT)) {
1739                 INT_COPY(free->bests[findex], data->hdr.bestfree[0].length, ARCH_CONVERT);
1740                 logfree = 1;
1741         }
1742         /*
1743          * Log the freespace entry if needed.
1744          */
1745         if (logfree)
1746                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1747         /*
1748          * If the caller didn't hand us the freespace block, drop it.
1749          */
1750         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1751                 xfs_da_buf_done(fbp);
1752         /*
1753          * Return the data block and offset in args, then drop the data block.
1754          */
1755         args->blkno = (xfs_dablk_t)dbno;
1756         args->index = INT_GET(*tagp, ARCH_CONVERT);
1757         xfs_da_buf_done(dbp);
1758         return 0;
1759 }
1760
1761 /*
1762  * Lookup an entry in a node-format directory.
1763  * All the real work happens in xfs_da_node_lookup_int.
1764  * The only real output is the inode number of the entry.
1765  */
1766 int                                             /* error */
1767 xfs_dir2_node_lookup(
1768         xfs_da_args_t   *args)                  /* operation arguments */
1769 {
1770         int             error;                  /* error return value */
1771         int             i;                      /* btree level */
1772         int             rval;                   /* operation return value */
1773         xfs_da_state_t  *state;                 /* btree cursor */
1774
1775         xfs_dir2_trace_args("node_lookup", args);
1776         /*
1777          * Allocate and initialize the btree cursor.
1778          */
1779         state = xfs_da_state_alloc();
1780         state->args = args;
1781         state->mp = args->dp->i_mount;
1782         state->blocksize = state->mp->m_dirblksize;
1783         state->node_ents = state->mp->m_dir_node_ents;
1784         /*
1785          * Fill in the path to the entry in the cursor.
1786          */
1787         error = xfs_da_node_lookup_int(state, &rval);
1788         if (error)
1789                 rval = error;
1790         /*
1791          * Release the btree blocks and leaf block.
1792          */
1793         for (i = 0; i < state->path.active; i++) {
1794                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1795                 state->path.blk[i].bp = NULL;
1796         }
1797         /*
1798          * Release the data block if we have it.
1799          */
1800         if (state->extravalid && state->extrablk.bp) {
1801                 xfs_da_brelse(args->trans, state->extrablk.bp);
1802                 state->extrablk.bp = NULL;
1803         }
1804         xfs_da_state_free(state);
1805         return rval;
1806 }
1807
1808 /*
1809  * Remove an entry from a node-format directory.
1810  */
1811 int                                             /* error */
1812 xfs_dir2_node_removename(
1813         xfs_da_args_t           *args)          /* operation arguments */
1814 {
1815         xfs_da_state_blk_t      *blk;           /* leaf block */
1816         int                     error;          /* error return value */
1817         int                     rval;           /* operation return value */
1818         xfs_da_state_t          *state;         /* btree cursor */
1819
1820         xfs_dir2_trace_args("node_removename", args);
1821         /*
1822          * Allocate and initialize the btree cursor.
1823          */
1824         state = xfs_da_state_alloc();
1825         state->args = args;
1826         state->mp = args->dp->i_mount;
1827         state->blocksize = state->mp->m_dirblksize;
1828         state->node_ents = state->mp->m_dir_node_ents;
1829         /*
1830          * Look up the entry we're deleting, set up the cursor.
1831          */
1832         error = xfs_da_node_lookup_int(state, &rval);
1833         if (error) {
1834                 rval = error;
1835         }
1836         /*
1837          * Didn't find it, upper layer screwed up.
1838          */
1839         if (rval != EEXIST) {
1840                 xfs_da_state_free(state);
1841                 return rval;
1842         }
1843         blk = &state->path.blk[state->path.active - 1];
1844         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1845         ASSERT(state->extravalid);
1846         /*
1847          * Remove the leaf and data entries.
1848          * Extrablk refers to the data block.
1849          */
1850         error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
1851                 &state->extrablk, &rval);
1852         if (error) {
1853                 return error;
1854         }
1855         /*
1856          * Fix the hash values up the btree.
1857          */
1858         xfs_da_fixhashpath(state, &state->path);
1859         /*
1860          * If we need to join leaf blocks, do it.
1861          */
1862         if (rval && state->path.active > 1)
1863                 error = xfs_da_join(state);
1864         /*
1865          * If no errors so far, try conversion to leaf format.
1866          */
1867         if (!error)
1868                 error = xfs_dir2_node_to_leaf(state);
1869         xfs_da_state_free(state);
1870         return error;
1871 }
1872
1873 /*
1874  * Replace an entry's inode number in a node-format directory.
1875  */
1876 int                                             /* error */
1877 xfs_dir2_node_replace(
1878         xfs_da_args_t           *args)          /* operation arguments */
1879 {
1880         xfs_da_state_blk_t      *blk;           /* leaf block */
1881         xfs_dir2_data_t         *data;          /* data block structure */
1882         xfs_dir2_data_entry_t   *dep;           /* data entry changed */
1883         int                     error;          /* error return value */
1884         int                     i;              /* btree level */
1885         xfs_ino_t               inum;           /* new inode number */
1886         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1887         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
1888         int                     rval;           /* internal return value */
1889         xfs_da_state_t          *state;         /* btree cursor */
1890
1891         xfs_dir2_trace_args("node_replace", args);
1892         /*
1893          * Allocate and initialize the btree cursor.
1894          */
1895         state = xfs_da_state_alloc();
1896         state->args = args;
1897         state->mp = args->dp->i_mount;
1898         state->blocksize = state->mp->m_dirblksize;
1899         state->node_ents = state->mp->m_dir_node_ents;
1900         inum = args->inumber;
1901         /*
1902          * Lookup the entry to change in the btree.
1903          */
1904         error = xfs_da_node_lookup_int(state, &rval);
1905         if (error) {
1906                 rval = error;
1907         }
1908         /*
1909          * It should be found, since the vnodeops layer has looked it up
1910          * and locked it.  But paranoia is good.
1911          */
1912         if (rval == EEXIST) {
1913                 /*
1914                  * Find the leaf entry.
1915                  */
1916                 blk = &state->path.blk[state->path.active - 1];
1917                 ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1918                 leaf = blk->bp->data;
1919                 lep = &leaf->ents[blk->index];
1920                 ASSERT(state->extravalid);
1921                 /*
1922                  * Point to the data entry.
1923                  */
1924                 data = state->extrablk.bp->data;
1925                 ASSERT(INT_GET(data->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC);
1926                 dep = (xfs_dir2_data_entry_t *)
1927                       ((char *)data +
1928                        XFS_DIR2_DATAPTR_TO_OFF(state->mp, INT_GET(lep->address, ARCH_CONVERT)));
1929                 ASSERT(inum != INT_GET(dep->inumber, ARCH_CONVERT));
1930                 /*
1931                  * Fill in the new inode number and log the entry.
1932                  */
1933                 INT_SET(dep->inumber, ARCH_CONVERT, inum);
1934                 xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
1935                 rval = 0;
1936         }
1937         /*
1938          * Didn't find it, and we're holding a data block.  Drop it.
1939          */
1940         else if (state->extravalid) {
1941                 xfs_da_brelse(args->trans, state->extrablk.bp);
1942                 state->extrablk.bp = NULL;
1943         }
1944         /*
1945          * Release all the buffers in the cursor.
1946          */
1947         for (i = 0; i < state->path.active; i++) {
1948                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1949                 state->path.blk[i].bp = NULL;
1950         }
1951         xfs_da_state_free(state);
1952         return rval;
1953 }
1954
1955 /*
1956  * Trim off a trailing empty freespace block.
1957  * Return (in rvalp) 1 if we did it, 0 if not.
1958  */
1959 int                                             /* error */
1960 xfs_dir2_node_trim_free(
1961         xfs_da_args_t           *args,          /* operation arguments */
1962         xfs_fileoff_t           fo,             /* free block number */
1963         int                     *rvalp)         /* out: did something */
1964 {
1965         xfs_dabuf_t             *bp;            /* freespace buffer */
1966         xfs_inode_t             *dp;            /* incore directory inode */
1967         int                     error;          /* error return code */
1968         xfs_dir2_free_t         *free;          /* freespace structure */
1969         xfs_mount_t             *mp;            /* filesystem mount point */
1970         xfs_trans_t             *tp;            /* transaction pointer */
1971
1972         dp = args->dp;
1973         mp = dp->i_mount;
1974         tp = args->trans;
1975         /*
1976          * Read the freespace block.
1977          */
1978         if (unlikely(error = xfs_da_read_buf(tp, dp, (xfs_dablk_t)fo, -2, &bp,
1979                         XFS_DATA_FORK))) {
1980                 return error;
1981         }
1982
1983         /*
1984          * There can be holes in freespace.  If fo is a hole, there's
1985          * nothing to do.
1986          */
1987         if (bp == NULL) {
1988                 return 0;
1989         }
1990         free = bp->data;
1991         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1992         /*
1993          * If there are used entries, there's nothing to do.
1994          */
1995         if (INT_GET(free->hdr.nused, ARCH_CONVERT) > 0) {
1996                 xfs_da_brelse(tp, bp);
1997                 *rvalp = 0;
1998                 return 0;
1999         }
2000         /*
2001          * Blow the block away.
2002          */
2003         if ((error =
2004             xfs_dir2_shrink_inode(args, XFS_DIR2_DA_TO_DB(mp, (xfs_dablk_t)fo),
2005                     bp))) {
2006                 /*
2007                  * Can't fail with ENOSPC since that only happens with no
2008                  * space reservation, when breaking up an extent into two
2009                  * pieces.  This is the last block of an extent.
2010                  */
2011                 ASSERT(error != ENOSPC);
2012                 xfs_da_brelse(tp, bp);
2013                 return error;
2014         }
2015         /*
2016          * Return that we succeeded.
2017          */
2018         *rvalp = 1;
2019         return 0;
2020 }