fs/xfs/xfs_dir2_node.c

   1 /*
   2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3  * Copyright (c) 2013 Red Hat, Inc.
   4  * All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it would be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write the Free Software Foundation,
  17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 #include "xfs.h"
  20 #include "xfs_fs.h"
  21 #include "xfs_types.h"
  22 #include "xfs_log.h"
  23 #include "xfs_trans.h"
  24 #include "xfs_sb.h"
  25 #include "xfs_ag.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_da_btree.h"
  28 #include "xfs_bmap_btree.h"
  29 #include "xfs_dinode.h"
  30 #include "xfs_inode.h"
  31 #include "xfs_bmap.h"
  32 #include "xfs_dir2_format.h"
  33 #include "xfs_dir2.h"
  34 #include "xfs_dir2_priv.h"
  35 #include "xfs_error.h"
  36 #include "xfs_trace.h"
  37 #include "xfs_buf_item.h"
  38 #include "xfs_cksum.h"
  39
  40 /*
  41  * Function declarations.
  42  */
  43 static int xfs_dir2_leafn_add(struct xfs_buf *bp, xfs_da_args_t *args,
  44                               int index);
  45 static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  46                                      xfs_da_state_blk_t *blk1,
  47                                      xfs_da_state_blk_t *blk2);
  48 static int xfs_dir2_leafn_remove(xfs_da_args_t *args, struct xfs_buf *bp,
  49                                  int index, xfs_da_state_blk_t *dblk,
  50                                  int *rval);
  51 static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  52                                      xfs_da_state_blk_t *fblk);
  53
  54 /*
  55  * Check internal consistency of a leafn block.
  56  */
  57 #ifdef DEBUG
  58 #define xfs_dir3_leaf_check(mp, bp) \
  59 do { \
  60         if (!xfs_dir3_leafn_check((mp), (bp))) \
  61                 ASSERT(0); \
  62 } while (0);
  63
  64 static bool
  65 xfs_dir3_leafn_check(
  66         struct xfs_mount        *mp,
  67         struct xfs_buf          *bp)
  68 {
  69         struct xfs_dir2_leaf    *leaf = bp->b_addr;
  70         struct xfs_dir3_icleaf_hdr leafhdr;
  71
  72         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
  73
  74         if (leafhdr.magic == XFS_DIR3_LEAFN_MAGIC) {
  75                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
  76                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
  77                         return false;
  78         } else if (leafhdr.magic != XFS_DIR2_LEAFN_MAGIC)
  79                 return false;
  80
  81         return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
  82 }
  83 #else
  84 #define xfs_dir3_leaf_check(mp, bp)
  85 #endif
  86
  87 static bool
  88 xfs_dir3_free_verify(
  89         struct xfs_buf          *bp)
  90 {
  91         struct xfs_mount        *mp = bp->b_target->bt_mount;
  92         struct xfs_dir2_free_hdr *hdr = bp->b_addr;
  93
  94         if (xfs_sb_version_hascrc(&mp->m_sb)) {
  95                 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  96
  97                 if (hdr3->magic != cpu_to_be32(XFS_DIR3_FREE_MAGIC))
  98                         return false;
  99                 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_uuid))
 100                         return false;
 101                 if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
 102                         return false;
 103         } else {
 104                 if (hdr->magic != cpu_to_be32(XFS_DIR2_FREE_MAGIC))
 105                         return false;
 106         }
 107
 108         /* XXX: should bounds check the xfs_dir3_icfree_hdr here */
 109
 110         return true;
 111 }
 112
 113 static void
 114 xfs_dir3_free_read_verify(
 115         struct xfs_buf  *bp)
 116 {
 117         struct xfs_mount        *mp = bp->b_target->bt_mount;
 118
 119         if ((xfs_sb_version_hascrc(&mp->m_sb) &&
 120              !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
 121                                           XFS_DIR3_FREE_CRC_OFF)) ||
 122             !xfs_dir3_free_verify(bp)) {
 123                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 124                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 125         }
 126 }
 127
 128 static void
 129 xfs_dir3_free_write_verify(
 130         struct xfs_buf  *bp)
 131 {
 132         struct xfs_mount        *mp = bp->b_target->bt_mount;
 133         struct xfs_buf_log_item *bip = bp->b_fspriv;
 134         struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 135
 136         if (!xfs_dir3_free_verify(bp)) {
 137                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 138                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 139                 return;
 140         }
 141
 142         if (!xfs_sb_version_hascrc(&mp->m_sb))
 143                 return;
 144
 145         if (bip)
 146                 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
 147
 148         xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_FREE_CRC_OFF);
 149 }
 150
 151 const struct xfs_buf_ops xfs_dir3_free_buf_ops = {
 152         .verify_read = xfs_dir3_free_read_verify,
 153         .verify_write = xfs_dir3_free_write_verify,
 154 };
 155
 156
 157 static int
 158 __xfs_dir3_free_read(
 159         struct xfs_trans        *tp,
 160         struct xfs_inode        *dp,
 161         xfs_dablk_t             fbno,
 162         xfs_daddr_t             mappedbno,
 163         struct xfs_buf          **bpp)
 164 {
 165         int                     err;
 166
 167         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 168                                 XFS_DATA_FORK, &xfs_dir3_free_buf_ops);
 169
 170         /* try read returns without an error or *bpp if it lands in a hole */
 171         if (!err && tp && *bpp)
 172                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF);
 173         return err;
 174 }
 175
 176 int
 177 xfs_dir2_free_read(
 178         struct xfs_trans        *tp,
 179         struct xfs_inode        *dp,
 180         xfs_dablk_t             fbno,
 181         struct xfs_buf          **bpp)
 182 {
 183         return __xfs_dir3_free_read(tp, dp, fbno, -1, bpp);
 184 }
 185
 186 static int
 187 xfs_dir2_free_try_read(
 188         struct xfs_trans        *tp,
 189         struct xfs_inode        *dp,
 190         xfs_dablk_t             fbno,
 191         struct xfs_buf          **bpp)
 192 {
 193         return __xfs_dir3_free_read(tp, dp, fbno, -2, bpp);
 194 }
 195
 196
 197 void
 198 xfs_dir3_free_hdr_from_disk(
 199         struct xfs_dir3_icfree_hdr      *to,
 200         struct xfs_dir2_free            *from)
 201 {
 202         if (from->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC)) {
 203                 to->magic = be32_to_cpu(from->hdr.magic);
 204                 to->firstdb = be32_to_cpu(from->hdr.firstdb);
 205                 to->nvalid = be32_to_cpu(from->hdr.nvalid);
 206                 to->nused = be32_to_cpu(from->hdr.nused);
 207         } else {
 208                 struct xfs_dir3_free_hdr *hdr3 = (struct xfs_dir3_free_hdr *)from;
 209
 210                 to->magic = be32_to_cpu(hdr3->hdr.magic);
 211                 to->firstdb = be32_to_cpu(hdr3->firstdb);
 212                 to->nvalid = be32_to_cpu(hdr3->nvalid);
 213                 to->nused = be32_to_cpu(hdr3->nused);
 214         }
 215
 216         ASSERT(to->magic == XFS_DIR2_FREE_MAGIC ||
 217                to->magic == XFS_DIR3_FREE_MAGIC);
 218 }
 219
 220 static void
 221 xfs_dir3_free_hdr_to_disk(
 222         struct xfs_dir2_free            *to,
 223         struct xfs_dir3_icfree_hdr      *from)
 224 {
 225         ASSERT(from->magic == XFS_DIR2_FREE_MAGIC ||
 226                from->magic == XFS_DIR3_FREE_MAGIC);
 227
 228         if (from->magic == XFS_DIR2_FREE_MAGIC) {
 229                 to->hdr.magic = cpu_to_be32(from->magic);
 230                 to->hdr.firstdb = cpu_to_be32(from->firstdb);
 231                 to->hdr.nvalid = cpu_to_be32(from->nvalid);
 232                 to->hdr.nused = cpu_to_be32(from->nused);
 233         } else {
 234                 struct xfs_dir3_free_hdr *hdr3 = (struct xfs_dir3_free_hdr *)to;
 235
 236                 hdr3->hdr.magic = cpu_to_be32(from->magic);
 237                 hdr3->firstdb = cpu_to_be32(from->firstdb);
 238                 hdr3->nvalid = cpu_to_be32(from->nvalid);
 239                 hdr3->nused = cpu_to_be32(from->nused);
 240         }
 241 }
 242
 243 static int
 244 xfs_dir3_free_get_buf(
 245         struct xfs_trans        *tp,
 246         struct xfs_inode        *dp,
 247         xfs_dir2_db_t           fbno,
 248         struct xfs_buf          **bpp)
 249 {
 250         struct xfs_mount        *mp = dp->i_mount;
 251         struct xfs_buf          *bp;
 252         int                     error;
 253         struct xfs_dir3_icfree_hdr hdr;
 254
 255         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, fbno),
 256                                    -1, &bp, XFS_DATA_FORK);
 257         if (error)
 258                 return error;
 259
 260         xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_FREE_BUF);
 261         bp->b_ops = &xfs_dir3_free_buf_ops;
 262
 263         /*
 264          * Initialize the new block to be empty, and remember
 265          * its first slot as our empty slot.
 266          */
 267         memset(bp->b_addr, 0, sizeof(struct xfs_dir3_free_hdr));
 268         memset(&hdr, 0, sizeof(hdr));
 269
 270         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 271                 struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 272
 273                 hdr.magic = XFS_DIR3_FREE_MAGIC;
 274
 275                 hdr3->hdr.blkno = cpu_to_be64(bp->b_bn);
 276                 hdr3->hdr.owner = cpu_to_be64(dp->i_ino);
 277                 uuid_copy(&hdr3->hdr.uuid, &mp->m_sb.sb_uuid);
 278         } else
 279                 hdr.magic = XFS_DIR2_FREE_MAGIC;
 280         xfs_dir3_free_hdr_to_disk(bp->b_addr, &hdr);
 281         *bpp = bp;
 282         return 0;
 283 }
 284
 285 /*
 286  * Log entries from a freespace block.
 287  */
 288 STATIC void
 289 xfs_dir2_free_log_bests(
 290         struct xfs_trans        *tp,
 291         struct xfs_buf          *bp,
 292         int                     first,          /* first entry to log */
 293         int                     last)           /* last entry to log */
 294 {
 295         xfs_dir2_free_t         *free;          /* freespace structure */
 296         __be16                  *bests;
 297
 298         free = bp->b_addr;
 299         bests = xfs_dir3_free_bests_p(tp->t_mountp, free);
 300         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 301                free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 302         xfs_trans_log_buf(tp, bp,
 303                 (uint)((char *)&bests[first] - (char *)free),
 304                 (uint)((char *)&bests[last] - (char *)free +
 305                        sizeof(bests[0]) - 1));
 306 }
 307
 308 /*
 309  * Log header from a freespace block.
 310  */
 311 static void
 312 xfs_dir2_free_log_header(
 313         struct xfs_trans        *tp,
 314         struct xfs_buf          *bp)
 315 {
 316 #ifdef DEBUG
 317         xfs_dir2_free_t         *free;          /* freespace structure */
 318
 319         free = bp->b_addr;
 320         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 321                free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 322 #endif
 323         xfs_trans_log_buf(tp, bp, 0, xfs_dir3_free_hdr_size(tp->t_mountp) - 1);
 324 }
 325
 326 /*
 327  * Convert a leaf-format directory to a node-format directory.
 328  * We need to change the magic number of the leaf block, and copy
 329  * the freespace table out of the leaf block into its own block.
 330  */
 331 int                                             /* error */
 332 xfs_dir2_leaf_to_node(
 333         xfs_da_args_t           *args,          /* operation arguments */
 334         struct xfs_buf          *lbp)           /* leaf buffer */
 335 {
 336         xfs_inode_t             *dp;            /* incore directory inode */
 337         int                     error;          /* error return value */
 338         struct xfs_buf          *fbp;           /* freespace buffer */
 339         xfs_dir2_db_t           fdb;            /* freespace block number */
 340         xfs_dir2_free_t         *free;          /* freespace structure */
 341         __be16                  *from;          /* pointer to freespace entry */
 342         int                     i;              /* leaf freespace index */
 343         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 344         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 345         xfs_mount_t             *mp;            /* filesystem mount point */
 346         int                     n;              /* count of live freespc ents */
 347         xfs_dir2_data_off_t     off;            /* freespace entry value */
 348         __be16                  *to;            /* pointer to freespace entry */
 349         xfs_trans_t             *tp;            /* transaction pointer */
 350         struct xfs_dir3_icfree_hdr freehdr;
 351
 352         trace_xfs_dir2_leaf_to_node(args);
 353
 354         dp = args->dp;
 355         mp = dp->i_mount;
 356         tp = args->trans;
 357         /*
 358          * Add a freespace block to the directory.
 359          */
 360         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 361                 return error;
 362         }
 363         ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 364         /*
 365          * Get the buffer for the new freespace block.
 366          */
 367         error = xfs_dir3_free_get_buf(tp, dp, fdb, &fbp);
 368         if (error)
 369                 return error;
 370
 371         free = fbp->b_addr;
 372         xfs_dir3_free_hdr_from_disk(&freehdr, free);
 373         leaf = lbp->b_addr;
 374         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 375         ASSERT(be32_to_cpu(ltp->bestcount) <=
 376                                 (uint)dp->i_d.di_size / mp->m_dirblksize);
 377
 378         /*
 379          * Copy freespace entries from the leaf block to the new block.
 380          * Count active entries.
 381          */
 382         from = xfs_dir2_leaf_bests_p(ltp);
 383         to = xfs_dir3_free_bests_p(mp, free);
 384         for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 385                 if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 386                         n++;
 387                 *to = cpu_to_be16(off);
 388         }
 389
 390         /*
 391          * Now initialize the freespace block header.
 392          */
 393         freehdr.nused = n;
 394         freehdr.nvalid = be32_to_cpu(ltp->bestcount);
 395
 396         xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
 397         xfs_dir2_free_log_bests(tp, fbp, 0, freehdr.nvalid - 1);
 398         xfs_dir2_free_log_header(tp, fbp);
 399
 400         /*
 401          * Converting the leaf to a leafnode is just a matter of changing the
 402          * magic number and the ops. Do the change directly to the buffer as
 403          * it's less work (and less code) than decoding the header to host
 404          * format and back again.
 405          */
 406         if (leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC))
 407                 leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 408         else
 409                 leaf->hdr.info.magic = cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 410         lbp->b_ops = &xfs_dir3_leafn_buf_ops;
 411         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAFN_BUF);
 412         xfs_dir3_leaf_log_header(tp, lbp);
 413         xfs_dir3_leaf_check(mp, lbp);
 414         return 0;
 415 }
 416
 417 /*
 418  * Add a leaf entry to a leaf block in a node-form directory.
 419  * The other work necessary is done from the caller.
 420  */
 421 static int                                      /* error */
 422 xfs_dir2_leafn_add(
 423         struct xfs_buf          *bp,            /* leaf buffer */
 424         xfs_da_args_t           *args,          /* operation arguments */
 425         int                     index)          /* insertion pt for new entry */
 426 {
 427         int                     compact;        /* compacting stale leaves */
 428         xfs_inode_t             *dp;            /* incore directory inode */
 429         int                     highstale;      /* next stale entry */
 430         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 431         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 432         int                     lfloghigh;      /* high leaf entry logging */
 433         int                     lfloglow;       /* low leaf entry logging */
 434         int                     lowstale;       /* previous stale entry */
 435         xfs_mount_t             *mp;            /* filesystem mount point */
 436         xfs_trans_t             *tp;            /* transaction pointer */
 437         struct xfs_dir3_icleaf_hdr leafhdr;
 438         struct xfs_dir2_leaf_entry *ents;
 439
 440         trace_xfs_dir2_leafn_add(args, index);
 441
 442         dp = args->dp;
 443         mp = dp->i_mount;
 444         tp = args->trans;
 445         leaf = bp->b_addr;
 446         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 447         ents = xfs_dir3_leaf_ents_p(leaf);
 448
 449         /*
 450          * Quick check just to make sure we are not going to index
 451          * into other peoples memory
 452          */
 453         if (index < 0)
 454                 return XFS_ERROR(EFSCORRUPTED);
 455
 456         /*
 457          * If there are already the maximum number of leaf entries in
 458          * the block, if there are no stale entries it won't fit.
 459          * Caller will do a split.  If there are stale entries we'll do
 460          * a compact.
 461          */
 462
 463         if (leafhdr.count == xfs_dir3_max_leaf_ents(mp, leaf)) {
 464                 if (!leafhdr.stale)
 465                         return XFS_ERROR(ENOSPC);
 466                 compact = leafhdr.stale > 1;
 467         } else
 468                 compact = 0;
 469         ASSERT(index == 0 || be32_to_cpu(ents[index - 1].hashval) <= args->hashval);
 470         ASSERT(index == leafhdr.count ||
 471                be32_to_cpu(ents[index].hashval) >= args->hashval);
 472
 473         if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 474                 return 0;
 475
 476         /*
 477          * Compact out all but one stale leaf entry.  Leaves behind
 478          * the entry closest to index.
 479          */
 480         if (compact)
 481                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 482                                          &highstale, &lfloglow, &lfloghigh);
 483         else if (leafhdr.stale) {
 484                 /*
 485                  * Set impossible logging indices for this case.
 486                  */
 487                 lfloglow = leafhdr.count;
 488                 lfloghigh = -1;
 489         }
 490
 491         /*
 492          * Insert the new entry, log everything.
 493          */
 494         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 495                                        highstale, &lfloglow, &lfloghigh);
 496
 497         lep->hashval = cpu_to_be32(args->hashval);
 498         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
 499                                 args->blkno, args->index));
 500
 501         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
 502         xfs_dir3_leaf_log_header(tp, bp);
 503         xfs_dir3_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 504         xfs_dir3_leaf_check(mp, bp);
 505         return 0;
 506 }
 507
 508 #ifdef DEBUG
 509 static void
 510 xfs_dir2_free_hdr_check(
 511         struct xfs_mount *mp,
 512         struct xfs_buf  *bp,
 513         xfs_dir2_db_t   db)
 514 {
 515         struct xfs_dir3_icfree_hdr hdr;
 516
 517         xfs_dir3_free_hdr_from_disk(&hdr, bp->b_addr);
 518
 519         ASSERT((hdr.firstdb % xfs_dir3_free_max_bests(mp)) == 0);
 520         ASSERT(hdr.firstdb <= db);
 521         ASSERT(db < hdr.firstdb + hdr.nvalid);
 522 }
 523 #else
 524 #define xfs_dir2_free_hdr_check(mp, dp, db)
 525 #endif  /* DEBUG */
 526
 527 /*
 528  * Return the last hash value in the leaf.
 529  * Stale entries are ok.
 530  */
 531 xfs_dahash_t                                    /* hash value */
 532 xfs_dir2_leafn_lasthash(
 533         struct xfs_buf  *bp,                    /* leaf buffer */
 534         int             *count)                 /* count of entries in leaf */
 535 {
 536         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 537         struct xfs_dir2_leaf_entry *ents;
 538         struct xfs_dir3_icleaf_hdr leafhdr;
 539
 540         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 541
 542         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
 543                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
 544
 545         if (count)
 546                 *count = leafhdr.count;
 547         if (!leafhdr.count)
 548                 return 0;
 549
 550         ents = xfs_dir3_leaf_ents_p(leaf);
 551         return be32_to_cpu(ents[leafhdr.count - 1].hashval);
 552 }
 553
 554 /*
 555  * Look up a leaf entry for space to add a name in a node-format leaf block.
 556  * The extrablk in state is a freespace block.
 557  */
 558 STATIC int
 559 xfs_dir2_leafn_lookup_for_addname(
 560         struct xfs_buf          *bp,            /* leaf buffer */
 561         xfs_da_args_t           *args,          /* operation arguments */
 562         int                     *indexp,        /* out: leaf entry index */
 563         xfs_da_state_t          *state)         /* state to fill in */
 564 {
 565         struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 566         xfs_dir2_db_t           curdb = -1;     /* current data block number */
 567         xfs_dir2_db_t           curfdb = -1;    /* current free block number */
 568         xfs_inode_t             *dp;            /* incore directory inode */
 569         int                     error;          /* error return value */
 570         int                     fi;             /* free entry index */
 571         xfs_dir2_free_t         *free = NULL;   /* free block structure */
 572         int                     index;          /* leaf entry index */
 573         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 574         int                     length;         /* length of new data entry */
 575         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 576         xfs_mount_t             *mp;            /* filesystem mount point */
 577         xfs_dir2_db_t           newdb;          /* new data block number */
 578         xfs_dir2_db_t           newfdb;         /* new free block number */
 579         xfs_trans_t             *tp;            /* transaction pointer */
 580         struct xfs_dir2_leaf_entry *ents;
 581         struct xfs_dir3_icleaf_hdr leafhdr;
 582
 583         dp = args->dp;
 584         tp = args->trans;
 585         mp = dp->i_mount;
 586         leaf = bp->b_addr;
 587         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 588         ents = xfs_dir3_leaf_ents_p(leaf);
 589
 590         xfs_dir3_leaf_check(mp, bp);
 591         ASSERT(leafhdr.count > 0);
 592
 593         /*
 594          * Look up the hash value in the leaf entries.
 595          */
 596         index = xfs_dir2_leaf_search_hash(args, bp);
 597         /*
 598          * Do we have a buffer coming in?
 599          */
 600         if (state->extravalid) {
 601                 /* If so, it's a free block buffer, get the block number. */
 602                 curbp = state->extrablk.bp;
 603                 curfdb = state->extrablk.blkno;
 604                 free = curbp->b_addr;
 605                 ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 606                        free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 607         }
 608         length = xfs_dir3_data_entsize(mp, args->namelen);
 609         /*
 610          * Loop over leaf entries with the right hash value.
 611          */
 612         for (lep = &ents[index];
 613              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 614              lep++, index++) {
 615                 /*
 616                  * Skip stale leaf entries.
 617                  */
 618                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 619                         continue;
 620                 /*
 621                  * Pull the data block number from the entry.
 622                  */
 623                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 624                 /*
 625                  * For addname, we're looking for a place to put the new entry.
 626                  * We want to use a data block with an entry of equal
 627                  * hash value to ours if there is one with room.
 628                  *
 629                  * If this block isn't the data block we already have
 630                  * in hand, take a look at it.
 631                  */
 632                 if (newdb != curdb) {
 633                         __be16 *bests;
 634
 635                         curdb = newdb;
 636                         /*
 637                          * Convert the data block to the free block
 638                          * holding its freespace information.
 639                          */
 640                         newfdb = xfs_dir2_db_to_fdb(mp, newdb);
 641                         /*
 642                          * If it's not the one we have in hand, read it in.
 643                          */
 644                         if (newfdb != curfdb) {
 645                                 /*
 646                                  * If we had one before, drop it.
 647                                  */
 648                                 if (curbp)
 649                                         xfs_trans_brelse(tp, curbp);
 650
 651                                 error = xfs_dir2_free_read(tp, dp,
 652                                                 xfs_dir2_db_to_da(mp, newfdb),
 653                                                 &curbp);
 654                                 if (error)
 655                                         return error;
 656                                 free = curbp->b_addr;
 657
 658                                 xfs_dir2_free_hdr_check(mp, curbp, curdb);
 659                         }
 660                         /*
 661                          * Get the index for our entry.
 662                          */
 663                         fi = xfs_dir2_db_to_fdindex(mp, curdb);
 664                         /*
 665                          * If it has room, return it.
 666                          */
 667                         bests = xfs_dir3_free_bests_p(mp, free);
 668                         if (unlikely(bests[fi] == cpu_to_be16(NULLDATAOFF))) {
 669                                 XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 670                                                         XFS_ERRLEVEL_LOW, mp);
 671                                 if (curfdb != newfdb)
 672                                         xfs_trans_brelse(tp, curbp);
 673                                 return XFS_ERROR(EFSCORRUPTED);
 674                         }
 675                         curfdb = newfdb;
 676                         if (be16_to_cpu(bests[fi]) >= length)
 677                                 goto out;
 678                 }
 679         }
 680         /* Didn't find any space */
 681         fi = -1;
 682 out:
 683         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 684         if (curbp) {
 685                 /* Giving back a free block. */
 686                 state->extravalid = 1;
 687                 state->extrablk.bp = curbp;
 688                 state->extrablk.index = fi;
 689                 state->extrablk.blkno = curfdb;
 690
 691                 /*
 692                  * Important: this magic number is not in the buffer - it's for
 693                  * buffer type information and therefore only the free/data type
 694                  * matters here, not whether CRCs are enabled or not.
 695                  */
 696                 state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 697         } else {
 698                 state->extravalid = 0;
 699         }
 700         /*
 701          * Return the index, that will be the insertion point.
 702          */
 703         *indexp = index;
 704         return XFS_ERROR(ENOENT);
 705 }
 706
 707 /*
 708  * Look up a leaf entry in a node-format leaf block.
 709  * The extrablk in state a data block.
 710  */
 711 STATIC int
 712 xfs_dir2_leafn_lookup_for_entry(
 713         struct xfs_buf          *bp,            /* leaf buffer */
 714         xfs_da_args_t           *args,          /* operation arguments */
 715         int                     *indexp,        /* out: leaf entry index */
 716         xfs_da_state_t          *state)         /* state to fill in */
 717 {
 718         struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 719         xfs_dir2_db_t           curdb = -1;     /* current data block number */
 720         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 721         xfs_inode_t             *dp;            /* incore directory inode */
 722         int                     error;          /* error return value */
 723         int                     index;          /* leaf entry index */
 724         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 725         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 726         xfs_mount_t             *mp;            /* filesystem mount point */
 727         xfs_dir2_db_t           newdb;          /* new data block number */
 728         xfs_trans_t             *tp;            /* transaction pointer */
 729         enum xfs_dacmp          cmp;            /* comparison result */
 730         struct xfs_dir2_leaf_entry *ents;
 731         struct xfs_dir3_icleaf_hdr leafhdr;
 732
 733         dp = args->dp;
 734         tp = args->trans;
 735         mp = dp->i_mount;
 736         leaf = bp->b_addr;
 737         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 738         ents = xfs_dir3_leaf_ents_p(leaf);
 739
 740         xfs_dir3_leaf_check(mp, bp);
 741         ASSERT(leafhdr.count > 0);
 742
 743         /*
 744          * Look up the hash value in the leaf entries.
 745          */
 746         index = xfs_dir2_leaf_search_hash(args, bp);
 747         /*
 748          * Do we have a buffer coming in?
 749          */
 750         if (state->extravalid) {
 751                 curbp = state->extrablk.bp;
 752                 curdb = state->extrablk.blkno;
 753         }
 754         /*
 755          * Loop over leaf entries with the right hash value.
 756          */
 757         for (lep = &ents[index];
 758              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 759              lep++, index++) {
 760                 /*
 761                  * Skip stale leaf entries.
 762                  */
 763                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 764                         continue;
 765                 /*
 766                  * Pull the data block number from the entry.
 767                  */
 768                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 769                 /*
 770                  * Not adding a new entry, so we really want to find
 771                  * the name given to us.
 772                  *
 773                  * If it's a different data block, go get it.
 774                  */
 775                 if (newdb != curdb) {
 776                         /*
 777                          * If we had a block before that we aren't saving
 778                          * for a CI name, drop it
 779                          */
 780                         if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 781                                                 curdb != state->extrablk.blkno))
 782                                 xfs_trans_brelse(tp, curbp);
 783                         /*
 784                          * If needing the block that is saved with a CI match,
 785                          * use it otherwise read in the new data block.
 786                          */
 787                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
 788                                         newdb == state->extrablk.blkno) {
 789                                 ASSERT(state->extravalid);
 790                                 curbp = state->extrablk.bp;
 791                         } else {
 792                                 error = xfs_dir3_data_read(tp, dp,
 793                                                 xfs_dir2_db_to_da(mp, newdb),
 794                                                 -1, &curbp);
 795                                 if (error)
 796                                         return error;
 797                         }
 798                         xfs_dir3_data_check(dp, curbp);
 799                         curdb = newdb;
 800                 }
 801                 /*
 802                  * Point to the data entry.
 803                  */
 804                 dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr +
 805                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
 806                 /*
 807                  * Compare the entry and if it's an exact match, return
 808                  * EEXIST immediately. If it's the first case-insensitive
 809                  * match, store the block & inode number and continue looking.
 810                  */
 811                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 812                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 813                         /* If there is a CI match block, drop it */
 814                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
 815                                                 curdb != state->extrablk.blkno)
 816                                 xfs_trans_brelse(tp, state->extrablk.bp);
 817                         args->cmpresult = cmp;
 818                         args->inumber = be64_to_cpu(dep->inumber);
 819                         args->filetype = xfs_dir3_dirent_get_ftype(mp, dep);
 820                         *indexp = index;
 821                         state->extravalid = 1;
 822                         state->extrablk.bp = curbp;
 823                         state->extrablk.blkno = curdb;
 824                         state->extrablk.index = (int)((char *)dep -
 825                                                         (char *)curbp->b_addr);
 826                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 827                         curbp->b_ops = &xfs_dir3_data_buf_ops;
 828                         xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 829                         if (cmp == XFS_CMP_EXACT)
 830                                 return XFS_ERROR(EEXIST);
 831                 }
 832         }
 833         ASSERT(index == leafhdr.count || (args->op_flags & XFS_DA_OP_OKNOENT));
 834         if (curbp) {
 835                 if (args->cmpresult == XFS_CMP_DIFFERENT) {
 836                         /* Giving back last used data block. */
 837                         state->extravalid = 1;
 838                         state->extrablk.bp = curbp;
 839                         state->extrablk.index = -1;
 840                         state->extrablk.blkno = curdb;
 841                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 842                         curbp->b_ops = &xfs_dir3_data_buf_ops;
 843                         xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 844                 } else {
 845                         /* If the curbp is not the CI match block, drop it */
 846                         if (state->extrablk.bp != curbp)
 847                                 xfs_trans_brelse(tp, curbp);
 848                 }
 849         } else {
 850                 state->extravalid = 0;
 851         }
 852         *indexp = index;
 853         return XFS_ERROR(ENOENT);
 854 }
 855
 856 /*
 857  * Look up a leaf entry in a node-format leaf block.
 858  * If this is an addname then the extrablk in state is a freespace block,
 859  * otherwise it's a data block.
 860  */
 861 int
 862 xfs_dir2_leafn_lookup_int(
 863         struct xfs_buf          *bp,            /* leaf buffer */
 864         xfs_da_args_t           *args,          /* operation arguments */
 865         int                     *indexp,        /* out: leaf entry index */
 866         xfs_da_state_t          *state)         /* state to fill in */
 867 {
 868         if (args->op_flags & XFS_DA_OP_ADDNAME)
 869                 return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 870                                                         state);
 871         return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 872 }
 873
 874 /*
 875  * Move count leaf entries from source to destination leaf.
 876  * Log entries and headers.  Stale entries are preserved.
 877  */
 878 static void
 879 xfs_dir3_leafn_moveents(
 880         xfs_da_args_t                   *args,  /* operation arguments */
 881         struct xfs_buf                  *bp_s,  /* source */
 882         struct xfs_dir3_icleaf_hdr      *shdr,
 883         struct xfs_dir2_leaf_entry      *sents,
 884         int                             start_s,/* source leaf index */
 885         struct xfs_buf                  *bp_d,  /* destination */
 886         struct xfs_dir3_icleaf_hdr      *dhdr,
 887         struct xfs_dir2_leaf_entry      *dents,
 888         int                             start_d,/* destination leaf index */
 889         int                             count)  /* count of leaves to copy */
 890 {
 891         struct xfs_trans                *tp = args->trans;
 892         int                             stale;  /* count stale leaves copied */
 893
 894         trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 895
 896         /*
 897          * Silently return if nothing to do.
 898          */
 899         if (count == 0)
 900                 return;
 901
 902         /*
 903          * If the destination index is not the end of the current
 904          * destination leaf entries, open up a hole in the destination
 905          * to hold the new entries.
 906          */
 907         if (start_d < dhdr->count) {
 908                 memmove(&dents[start_d + count], &dents[start_d],
 909                         (dhdr->count - start_d) * sizeof(xfs_dir2_leaf_entry_t));
 910                 xfs_dir3_leaf_log_ents(tp, bp_d, start_d + count,
 911                                        count + dhdr->count - 1);
 912         }
 913         /*
 914          * If the source has stale leaves, count the ones in the copy range
 915          * so we can update the header correctly.
 916          */
 917         if (shdr->stale) {
 918                 int     i;                      /* temp leaf index */
 919
 920                 for (i = start_s, stale = 0; i < start_s + count; i++) {
 921                         if (sents[i].address ==
 922                                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 923                                 stale++;
 924                 }
 925         } else
 926                 stale = 0;
 927         /*
 928          * Copy the leaf entries from source to destination.
 929          */
 930         memcpy(&dents[start_d], &sents[start_s],
 931                 count * sizeof(xfs_dir2_leaf_entry_t));
 932         xfs_dir3_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 933
 934         /*
 935          * If there are source entries after the ones we copied,
 936          * delete the ones we copied by sliding the next ones down.
 937          */
 938         if (start_s + count < shdr->count) {
 939                 memmove(&sents[start_s], &sents[start_s + count],
 940                         count * sizeof(xfs_dir2_leaf_entry_t));
 941                 xfs_dir3_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 942         }
 943
 944         /*
 945          * Update the headers and log them.
 946          */
 947         shdr->count -= count;
 948         shdr->stale -= stale;
 949         dhdr->count += count;
 950         dhdr->stale += stale;
 951 }
 952
 953 /*
 954  * Determine the sort order of two leaf blocks.
 955  * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 956  */
 957 int                                             /* sort order */
 958 xfs_dir2_leafn_order(
 959         struct xfs_buf          *leaf1_bp,              /* leaf1 buffer */
 960         struct xfs_buf          *leaf2_bp)              /* leaf2 buffer */
 961 {
 962         struct xfs_dir2_leaf    *leaf1 = leaf1_bp->b_addr;
 963         struct xfs_dir2_leaf    *leaf2 = leaf2_bp->b_addr;
 964         struct xfs_dir2_leaf_entry *ents1;
 965         struct xfs_dir2_leaf_entry *ents2;
 966         struct xfs_dir3_icleaf_hdr hdr1;
 967         struct xfs_dir3_icleaf_hdr hdr2;
 968
 969         xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
 970         xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
 971         ents1 = xfs_dir3_leaf_ents_p(leaf1);
 972         ents2 = xfs_dir3_leaf_ents_p(leaf2);
 973
 974         if (hdr1.count > 0 && hdr2.count > 0 &&
 975             (be32_to_cpu(ents2[0].hashval) < be32_to_cpu(ents1[0].hashval) ||
 976              be32_to_cpu(ents2[hdr2.count - 1].hashval) <
 977                                 be32_to_cpu(ents1[hdr1.count - 1].hashval)))
 978                 return 1;
 979         return 0;
 980 }
 981
 982 /*
 983  * Rebalance leaf entries between two leaf blocks.
 984  * This is actually only called when the second block is new,
 985  * though the code deals with the general case.
 986  * A new entry will be inserted in one of the blocks, and that
 987  * entry is taken into account when balancing.
 988  */
 989 static void
 990 xfs_dir2_leafn_rebalance(
 991         xfs_da_state_t          *state,         /* btree cursor */
 992         xfs_da_state_blk_t      *blk1,          /* first btree block */
 993         xfs_da_state_blk_t      *blk2)          /* second btree block */
 994 {
 995         xfs_da_args_t           *args;          /* operation arguments */
 996         int                     count;          /* count (& direction) leaves */
 997         int                     isleft;         /* new goes in left leaf */
 998         xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 999         xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
1000         int                     mid;            /* midpoint leaf index */
1001 #if defined(DEBUG) || defined(XFS_WARN)
1002         int                     oldstale;       /* old count of stale leaves */
1003 #endif
1004         int                     oldsum;         /* old total leaf count */
1005         int                     swap;           /* swapped leaf blocks */
1006         struct xfs_dir2_leaf_entry *ents1;
1007         struct xfs_dir2_leaf_entry *ents2;
1008         struct xfs_dir3_icleaf_hdr hdr1;
1009         struct xfs_dir3_icleaf_hdr hdr2;
1010
1011         args = state->args;
1012         /*
1013          * If the block order is wrong, swap the arguments.
1014          */
1015         if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
1016                 xfs_da_state_blk_t      *tmp;   /* temp for block swap */
1017
1018                 tmp = blk1;
1019                 blk1 = blk2;
1020                 blk2 = tmp;
1021         }
1022         leaf1 = blk1->bp->b_addr;
1023         leaf2 = blk2->bp->b_addr;
1024         xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
1025         xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
1026         ents1 = xfs_dir3_leaf_ents_p(leaf1);
1027         ents2 = xfs_dir3_leaf_ents_p(leaf2);
1028
1029         oldsum = hdr1.count + hdr2.count;
1030 #if defined(DEBUG) || defined(XFS_WARN)
1031         oldstale = hdr1.stale + hdr2.stale;
1032 #endif
1033         mid = oldsum >> 1;
1034
1035         /*
1036          * If the old leaf count was odd then the new one will be even,
1037          * so we need to divide the new count evenly.
1038          */
1039         if (oldsum & 1) {
1040                 xfs_dahash_t    midhash;        /* middle entry hash value */
1041
1042                 if (mid >= hdr1.count)
1043                         midhash = be32_to_cpu(ents2[mid - hdr1.count].hashval);
1044                 else
1045                         midhash = be32_to_cpu(ents1[mid].hashval);
1046                 isleft = args->hashval <= midhash;
1047         }
1048         /*
1049          * If the old count is even then the new count is odd, so there's
1050          * no preferred side for the new entry.
1051          * Pick the left one.
1052          */
1053         else
1054                 isleft = 1;
1055         /*
1056          * Calculate moved entry count.  Positive means left-to-right,
1057          * negative means right-to-left.  Then move the entries.
1058          */
1059         count = hdr1.count - mid + (isleft == 0);
1060         if (count > 0)
1061                 xfs_dir3_leafn_moveents(args, blk1->bp, &hdr1, ents1,
1062                                         hdr1.count - count, blk2->bp,
1063                                         &hdr2, ents2, 0, count);
1064         else if (count < 0)
1065                 xfs_dir3_leafn_moveents(args, blk2->bp, &hdr2, ents2, 0,
1066                                         blk1->bp, &hdr1, ents1,
1067                                         hdr1.count, count);
1068
1069         ASSERT(hdr1.count + hdr2.count == oldsum);
1070         ASSERT(hdr1.stale + hdr2.stale == oldstale);
1071
1072         /* log the changes made when moving the entries */
1073         xfs_dir3_leaf_hdr_to_disk(leaf1, &hdr1);
1074         xfs_dir3_leaf_hdr_to_disk(leaf2, &hdr2);
1075         xfs_dir3_leaf_log_header(args->trans, blk1->bp);
1076         xfs_dir3_leaf_log_header(args->trans, blk2->bp);
1077
1078         xfs_dir3_leaf_check(args->dp->i_mount, blk1->bp);
1079         xfs_dir3_leaf_check(args->dp->i_mount, blk2->bp);
1080
1081         /*
1082          * Mark whether we're inserting into the old or new leaf.
1083          */
1084         if (hdr1.count < hdr2.count)
1085                 state->inleaf = swap;
1086         else if (hdr1.count > hdr2.count)
1087                 state->inleaf = !swap;
1088         else
1089                 state->inleaf = swap ^ (blk1->index <= hdr1.count);
1090         /*
1091          * Adjust the expected index for insertion.
1092          */
1093         if (!state->inleaf)
1094                 blk2->index = blk1->index - hdr1.count;
1095
1096         /*
1097          * Finally sanity check just to make sure we are not returning a
1098          * negative index
1099          */
1100         if(blk2->index < 0) {
1101                 state->inleaf = 1;
1102                 blk2->index = 0;
1103                 xfs_alert(args->dp->i_mount,
1104         "%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
1105                         __func__, blk1->index);
1106         }
1107 }
1108
1109 static int
1110 xfs_dir3_data_block_free(
1111         xfs_da_args_t           *args,
1112         struct xfs_dir2_data_hdr *hdr,
1113         struct xfs_dir2_free    *free,
1114         xfs_dir2_db_t           fdb,
1115         int                     findex,
1116         struct xfs_buf          *fbp,
1117         int                     longest)
1118 {
1119         struct xfs_trans        *tp = args->trans;
1120         int                     logfree = 0;
1121         __be16                  *bests;
1122         struct xfs_dir3_icfree_hdr freehdr;
1123
1124         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1125
1126         bests = xfs_dir3_free_bests_p(tp->t_mountp, free);
1127         if (hdr) {
1128                 /*
1129                  * Data block is not empty, just set the free entry to the new
1130                  * value.
1131                  */
1132                 bests[findex] = cpu_to_be16(longest);
1133                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1134                 return 0;
1135         }
1136
1137         /* One less used entry in the free table. */
1138         freehdr.nused--;
1139
1140         /*
1141          * If this was the last entry in the table, we can trim the table size
1142          * back.  There might be other entries at the end referring to
1143          * non-existent data blocks, get those too.
1144          */
1145         if (findex == freehdr.nvalid - 1) {
1146                 int     i;              /* free entry index */
1147
1148                 for (i = findex - 1; i >= 0; i--) {
1149                         if (bests[i] != cpu_to_be16(NULLDATAOFF))
1150                                 break;
1151                 }
1152                 freehdr.nvalid = i + 1;
1153                 logfree = 0;
1154         } else {
1155                 /* Not the last entry, just punch it out.  */
1156                 bests[findex] = cpu_to_be16(NULLDATAOFF);
1157                 logfree = 1;
1158         }
1159
1160         xfs_dir3_free_hdr_to_disk(free, &freehdr);
1161         xfs_dir2_free_log_header(tp, fbp);
1162
1163         /*
1164          * If there are no useful entries left in the block, get rid of the
1165          * block if we can.
1166          */
1167         if (!freehdr.nused) {
1168                 int error;
1169
1170                 error = xfs_dir2_shrink_inode(args, fdb, fbp);
1171                 if (error == 0) {
1172                         fbp = NULL;
1173                         logfree = 0;
1174                 } else if (error != ENOSPC || args->total != 0)
1175                         return error;
1176                 /*
1177                  * It's possible to get ENOSPC if there is no
1178                  * space reservation.  In this case some one
1179                  * else will eventually get rid of this block.
1180                  */
1181         }
1182
1183         /* Log the free entry that changed, unless we got rid of it.  */
1184         if (logfree)
1185                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1186         return 0;
1187 }
1188
1189 /*
1190  * Remove an entry from a node directory.
1191  * This removes the leaf entry and the data entry,
1192  * and updates the free block if necessary.
1193  */
1194 static int                                      /* error */
1195 xfs_dir2_leafn_remove(
1196         xfs_da_args_t           *args,          /* operation arguments */
1197         struct xfs_buf          *bp,            /* leaf buffer */
1198         int                     index,          /* leaf entry index */
1199         xfs_da_state_blk_t      *dblk,          /* data block */
1200         int                     *rval)          /* resulting block needs join */
1201 {
1202         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1203         xfs_dir2_db_t           db;             /* data block number */
1204         struct xfs_buf          *dbp;           /* data block buffer */
1205         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1206         xfs_inode_t             *dp;            /* incore directory inode */
1207         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1208         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1209         int                     longest;        /* longest data free entry */
1210         int                     off;            /* data block entry offset */
1211         xfs_mount_t             *mp;            /* filesystem mount point */
1212         int                     needlog;        /* need to log data header */
1213         int                     needscan;       /* need to rescan data frees */
1214         xfs_trans_t             *tp;            /* transaction pointer */
1215         struct xfs_dir2_data_free *bf;          /* bestfree table */
1216         struct xfs_dir3_icleaf_hdr leafhdr;
1217         struct xfs_dir2_leaf_entry *ents;
1218
1219         trace_xfs_dir2_leafn_remove(args, index);
1220
1221         dp = args->dp;
1222         tp = args->trans;
1223         mp = dp->i_mount;
1224         leaf = bp->b_addr;
1225         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1226         ents = xfs_dir3_leaf_ents_p(leaf);
1227
1228         /*
1229          * Point to the entry we're removing.
1230          */
1231         lep = &ents[index];
1232
1233         /*
1234          * Extract the data block and offset from the entry.
1235          */
1236         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1237         ASSERT(dblk->blkno == db);
1238         off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
1239         ASSERT(dblk->index == off);
1240
1241         /*
1242          * Kill the leaf entry by marking it stale.
1243          * Log the leaf block changes.
1244          */
1245         leafhdr.stale++;
1246         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1247         xfs_dir3_leaf_log_header(tp, bp);
1248
1249         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1250         xfs_dir3_leaf_log_ents(tp, bp, index, index);
1251
1252         /*
1253          * Make the data entry free.  Keep track of the longest freespace
1254          * in the data block in case it changes.
1255          */
1256         dbp = dblk->bp;
1257         hdr = dbp->b_addr;
1258         dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
1259         bf = xfs_dir3_data_bestfree_p(hdr);
1260         longest = be16_to_cpu(bf[0].length);
1261         needlog = needscan = 0;
1262         xfs_dir2_data_make_free(tp, dbp, off,
1263                 xfs_dir3_data_entsize(mp, dep->namelen), &needlog, &needscan);
1264         /*
1265          * Rescan the data block freespaces for bestfree.
1266          * Log the data block header if needed.
1267          */
1268         if (needscan)
1269                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1270         if (needlog)
1271                 xfs_dir2_data_log_header(tp, dbp);
1272         xfs_dir3_data_check(dp, dbp);
1273         /*
1274          * If the longest data block freespace changes, need to update
1275          * the corresponding freeblock entry.
1276          */
1277         if (longest < be16_to_cpu(bf[0].length)) {
1278                 int             error;          /* error return value */
1279                 struct xfs_buf  *fbp;           /* freeblock buffer */
1280                 xfs_dir2_db_t   fdb;            /* freeblock block number */
1281                 int             findex;         /* index in freeblock entries */
1282                 xfs_dir2_free_t *free;          /* freeblock structure */
1283
1284                 /*
1285                  * Convert the data block number to a free block,
1286                  * read in the free block.
1287                  */
1288                 fdb = xfs_dir2_db_to_fdb(mp, db);
1289                 error = xfs_dir2_free_read(tp, dp, xfs_dir2_db_to_da(mp, fdb),
1290                                            &fbp);
1291                 if (error)
1292                         return error;
1293                 free = fbp->b_addr;
1294 #ifdef DEBUG
1295         {
1296                 struct xfs_dir3_icfree_hdr freehdr;
1297                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1298                 ASSERT(freehdr.firstdb == xfs_dir3_free_max_bests(mp) *
1299                                           (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
1300         }
1301 #endif
1302                 /*
1303                  * Calculate which entry we need to fix.
1304                  */
1305                 findex = xfs_dir2_db_to_fdindex(mp, db);
1306                 longest = be16_to_cpu(bf[0].length);
1307                 /*
1308                  * If the data block is now empty we can get rid of it
1309                  * (usually).
1310                  */
1311                 if (longest == mp->m_dirblksize -
1312                                xfs_dir3_data_entry_offset(hdr)) {
1313                         /*
1314                          * Try to punch out the data block.
1315                          */
1316                         error = xfs_dir2_shrink_inode(args, db, dbp);
1317                         if (error == 0) {
1318                                 dblk->bp = NULL;
1319                                 hdr = NULL;
1320                         }
1321                         /*
1322                          * We can get ENOSPC if there's no space reservation.
1323                          * In this case just drop the buffer and some one else
1324                          * will eventually get rid of the empty block.
1325                          */
1326                         else if (!(error == ENOSPC && args->total == 0))
1327                                 return error;
1328                 }
1329                 /*
1330                  * If we got rid of the data block, we can eliminate that entry
1331                  * in the free block.
1332                  */
1333                 error = xfs_dir3_data_block_free(args, hdr, free,
1334                                                  fdb, findex, fbp, longest);
1335                 if (error)
1336                         return error;
1337         }
1338
1339         xfs_dir3_leaf_check(mp, bp);
1340         /*
1341          * Return indication of whether this leaf block is empty enough
1342          * to justify trying to join it with a neighbor.
1343          */
1344         *rval = (xfs_dir3_leaf_hdr_size(leaf) +
1345                  (uint)sizeof(ents[0]) * (leafhdr.count - leafhdr.stale)) <
1346                 mp->m_dir_magicpct;
1347         return 0;
1348 }
1349
1350 /*
1351  * Split the leaf entries in the old block into old and new blocks.
1352  */
1353 int                                             /* error */
1354 xfs_dir2_leafn_split(
1355         xfs_da_state_t          *state,         /* btree cursor */
1356         xfs_da_state_blk_t      *oldblk,        /* original block */
1357         xfs_da_state_blk_t      *newblk)        /* newly created block */
1358 {
1359         xfs_da_args_t           *args;          /* operation arguments */
1360         xfs_dablk_t             blkno;          /* new leaf block number */
1361         int                     error;          /* error return value */
1362         xfs_mount_t             *mp;            /* filesystem mount point */
1363
1364         /*
1365          * Allocate space for a new leaf node.
1366          */
1367         args = state->args;
1368         mp = args->dp->i_mount;
1369         ASSERT(args != NULL);
1370         ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1371         error = xfs_da_grow_inode(args, &blkno);
1372         if (error) {
1373                 return error;
1374         }
1375         /*
1376          * Initialize the new leaf block.
1377          */
1378         error = xfs_dir3_leaf_get_buf(args, xfs_dir2_da_to_db(mp, blkno),
1379                                       &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1380         if (error)
1381                 return error;
1382
1383         newblk->blkno = blkno;
1384         newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1385         /*
1386          * Rebalance the entries across the two leaves, link the new
1387          * block into the leaves.
1388          */
1389         xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1390         error = xfs_da3_blk_link(state, oldblk, newblk);
1391         if (error) {
1392                 return error;
1393         }
1394         /*
1395          * Insert the new entry in the correct block.
1396          */
1397         if (state->inleaf)
1398                 error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1399         else
1400                 error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1401         /*
1402          * Update last hashval in each block since we added the name.
1403          */
1404         oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1405         newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1406         xfs_dir3_leaf_check(mp, oldblk->bp);
1407         xfs_dir3_leaf_check(mp, newblk->bp);
1408         return error;
1409 }
1410
1411 /*
1412  * Check a leaf block and its neighbors to see if the block should be
1413  * collapsed into one or the other neighbor.  Always keep the block
1414  * with the smaller block number.
1415  * If the current block is over 50% full, don't try to join it, return 0.
1416  * If the block is empty, fill in the state structure and return 2.
1417  * If it can be collapsed, fill in the state structure and return 1.
1418  * If nothing can be done, return 0.
1419  */
1420 int                                             /* error */
1421 xfs_dir2_leafn_toosmall(
1422         xfs_da_state_t          *state,         /* btree cursor */
1423         int                     *action)        /* resulting action to take */
1424 {
1425         xfs_da_state_blk_t      *blk;           /* leaf block */
1426         xfs_dablk_t             blkno;          /* leaf block number */
1427         struct xfs_buf          *bp;            /* leaf buffer */
1428         int                     bytes;          /* bytes in use */
1429         int                     count;          /* leaf live entry count */
1430         int                     error;          /* error return value */
1431         int                     forward;        /* sibling block direction */
1432         int                     i;              /* sibling counter */
1433         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1434         int                     rval;           /* result from path_shift */
1435         struct xfs_dir3_icleaf_hdr leafhdr;
1436         struct xfs_dir2_leaf_entry *ents;
1437
1438         /*
1439          * Check for the degenerate case of the block being over 50% full.
1440          * If so, it's not worth even looking to see if we might be able
1441          * to coalesce with a sibling.
1442          */
1443         blk = &state->path.blk[state->path.active - 1];
1444         leaf = blk->bp->b_addr;
1445         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1446         ents = xfs_dir3_leaf_ents_p(leaf);
1447         xfs_dir3_leaf_check(state->args->dp->i_mount, blk->bp);
1448
1449         count = leafhdr.count - leafhdr.stale;
1450         bytes = xfs_dir3_leaf_hdr_size(leaf) + count * sizeof(ents[0]);
1451         if (bytes > (state->blocksize >> 1)) {
1452                 /*
1453                  * Blk over 50%, don't try to join.
1454                  */
1455                 *action = 0;
1456                 return 0;
1457         }
1458         /*
1459          * Check for the degenerate case of the block being empty.
1460          * If the block is empty, we'll simply delete it, no need to
1461          * coalesce it with a sibling block.  We choose (arbitrarily)
1462          * to merge with the forward block unless it is NULL.
1463          */
1464         if (count == 0) {
1465                 /*
1466                  * Make altpath point to the block we want to keep and
1467                  * path point to the block we want to drop (this one).
1468                  */
1469                 forward = (leafhdr.forw != 0);
1470                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1471                 error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1472                         &rval);
1473                 if (error)
1474                         return error;
1475                 *action = rval ? 2 : 0;
1476                 return 0;
1477         }
1478         /*
1479          * Examine each sibling block to see if we can coalesce with
1480          * at least 25% free space to spare.  We need to figure out
1481          * whether to merge with the forward or the backward block.
1482          * We prefer coalescing with the lower numbered sibling so as
1483          * to shrink a directory over time.
1484          */
1485         forward = leafhdr.forw < leafhdr.back;
1486         for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1487                 struct xfs_dir3_icleaf_hdr hdr2;
1488
1489                 blkno = forward ? leafhdr.forw : leafhdr.back;
1490                 if (blkno == 0)
1491                         continue;
1492                 /*
1493                  * Read the sibling leaf block.
1494                  */
1495                 error = xfs_dir3_leafn_read(state->args->trans, state->args->dp,
1496                                             blkno, -1, &bp);
1497                 if (error)
1498                         return error;
1499
1500                 /*
1501                  * Count bytes in the two blocks combined.
1502                  */
1503                 count = leafhdr.count - leafhdr.stale;
1504                 bytes = state->blocksize - (state->blocksize >> 2);
1505
1506                 leaf = bp->b_addr;
1507                 xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf);
1508                 ents = xfs_dir3_leaf_ents_p(leaf);
1509                 count += hdr2.count - hdr2.stale;
1510                 bytes -= count * sizeof(ents[0]);
1511
1512                 /*
1513                  * Fits with at least 25% to spare.
1514                  */
1515                 if (bytes >= 0)
1516                         break;
1517                 xfs_trans_brelse(state->args->trans, bp);
1518         }
1519         /*
1520          * Didn't like either block, give up.
1521          */
1522         if (i >= 2) {
1523                 *action = 0;
1524                 return 0;
1525         }
1526
1527         /*
1528          * Make altpath point to the block we want to keep (the lower
1529          * numbered block) and path point to the block we want to drop.
1530          */
1531         memcpy(&state->altpath, &state->path, sizeof(state->path));
1532         if (blkno < blk->blkno)
1533                 error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1534                         &rval);
1535         else
1536                 error = xfs_da3_path_shift(state, &state->path, forward, 0,
1537                         &rval);
1538         if (error) {
1539                 return error;
1540         }
1541         *action = rval ? 0 : 1;
1542         return 0;
1543 }
1544
1545 /*
1546  * Move all the leaf entries from drop_blk to save_blk.
1547  * This is done as part of a join operation.
1548  */
1549 void
1550 xfs_dir2_leafn_unbalance(
1551         xfs_da_state_t          *state,         /* cursor */
1552         xfs_da_state_blk_t      *drop_blk,      /* dead block */
1553         xfs_da_state_blk_t      *save_blk)      /* surviving block */
1554 {
1555         xfs_da_args_t           *args;          /* operation arguments */
1556         xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1557         xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1558         struct xfs_dir3_icleaf_hdr savehdr;
1559         struct xfs_dir3_icleaf_hdr drophdr;
1560         struct xfs_dir2_leaf_entry *sents;
1561         struct xfs_dir2_leaf_entry *dents;
1562
1563         args = state->args;
1564         ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1565         ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1566         drop_leaf = drop_blk->bp->b_addr;
1567         save_leaf = save_blk->bp->b_addr;
1568
1569         xfs_dir3_leaf_hdr_from_disk(&savehdr, save_leaf);
1570         xfs_dir3_leaf_hdr_from_disk(&drophdr, drop_leaf);
1571         sents = xfs_dir3_leaf_ents_p(save_leaf);
1572         dents = xfs_dir3_leaf_ents_p(drop_leaf);
1573
1574         /*
1575          * If there are any stale leaf entries, take this opportunity
1576          * to purge them.
1577          */
1578         if (drophdr.stale)
1579                 xfs_dir3_leaf_compact(args, &drophdr, drop_blk->bp);
1580         if (savehdr.stale)
1581                 xfs_dir3_leaf_compact(args, &savehdr, save_blk->bp);
1582
1583         /*
1584          * Move the entries from drop to the appropriate end of save.
1585          */
1586         drop_blk->hashval = be32_to_cpu(dents[drophdr.count - 1].hashval);
1587         if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1588                 xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1589                                         save_blk->bp, &savehdr, sents, 0,
1590                                         drophdr.count);
1591         else
1592                 xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1593                                         save_blk->bp, &savehdr, sents,
1594                                         savehdr.count, drophdr.count);
1595         save_blk->hashval = be32_to_cpu(sents[savehdr.count - 1].hashval);
1596
1597         /* log the changes made when moving the entries */
1598         xfs_dir3_leaf_hdr_to_disk(save_leaf, &savehdr);
1599         xfs_dir3_leaf_hdr_to_disk(drop_leaf, &drophdr);
1600         xfs_dir3_leaf_log_header(args->trans, save_blk->bp);
1601         xfs_dir3_leaf_log_header(args->trans, drop_blk->bp);
1602
1603         xfs_dir3_leaf_check(args->dp->i_mount, save_blk->bp);
1604         xfs_dir3_leaf_check(args->dp->i_mount, drop_blk->bp);
1605 }
1606
1607 /*
1608  * Top-level node form directory addname routine.
1609  */
1610 int                                             /* error */
1611 xfs_dir2_node_addname(
1612         xfs_da_args_t           *args)          /* operation arguments */
1613 {
1614         xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1615         int                     error;          /* error return value */
1616         int                     rval;           /* sub-return value */
1617         xfs_da_state_t          *state;         /* btree cursor */
1618
1619         trace_xfs_dir2_node_addname(args);
1620
1621         /*
1622          * Allocate and initialize the state (btree cursor).
1623          */
1624         state = xfs_da_state_alloc();
1625         state->args = args;
1626         state->mp = args->dp->i_mount;
1627         state->blocksize = state->mp->m_dirblksize;
1628         state->node_ents = state->mp->m_dir_node_ents;
1629         /*
1630          * Look up the name.  We're not supposed to find it, but
1631          * this gives us the insertion point.
1632          */
1633         error = xfs_da3_node_lookup_int(state, &rval);
1634         if (error)
1635                 rval = error;
1636         if (rval != ENOENT) {
1637                 goto done;
1638         }
1639         /*
1640          * Add the data entry to a data block.
1641          * Extravalid is set to a freeblock found by lookup.
1642          */
1643         rval = xfs_dir2_node_addname_int(args,
1644                 state->extravalid ? &state->extrablk : NULL);
1645         if (rval) {
1646                 goto done;
1647         }
1648         blk = &state->path.blk[state->path.active - 1];
1649         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1650         /*
1651          * Add the new leaf entry.
1652          */
1653         rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1654         if (rval == 0) {
1655                 /*
1656                  * It worked, fix the hash values up the btree.
1657                  */
1658                 if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1659                         xfs_da3_fixhashpath(state, &state->path);
1660         } else {
1661                 /*
1662                  * It didn't work, we need to split the leaf block.
1663                  */
1664                 if (args->total == 0) {
1665                         ASSERT(rval == ENOSPC);
1666                         goto done;
1667                 }
1668                 /*
1669                  * Split the leaf block and insert the new entry.
1670                  */
1671                 rval = xfs_da3_split(state);
1672         }
1673 done:
1674         xfs_da_state_free(state);
1675         return rval;
1676 }
1677
1678 /*
1679  * Add the data entry for a node-format directory name addition.
1680  * The leaf entry is added in xfs_dir2_leafn_add.
1681  * We may enter with a freespace block that the lookup found.
1682  */
1683 static int                                      /* error */
1684 xfs_dir2_node_addname_int(
1685         xfs_da_args_t           *args,          /* operation arguments */
1686         xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1687 {
1688         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1689         xfs_dir2_db_t           dbno;           /* data block number */
1690         struct xfs_buf          *dbp;           /* data block buffer */
1691         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1692         xfs_inode_t             *dp;            /* incore directory inode */
1693         xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1694         int                     error;          /* error return value */
1695         xfs_dir2_db_t           fbno;           /* freespace block number */
1696         struct xfs_buf          *fbp;           /* freespace buffer */
1697         int                     findex;         /* freespace entry index */
1698         xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1699         xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1700         xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1701         int                     length;         /* length of the new entry */
1702         int                     logfree;        /* need to log free entry */
1703         xfs_mount_t             *mp;            /* filesystem mount point */
1704         int                     needlog;        /* need to log data header */
1705         int                     needscan;       /* need to rescan data frees */
1706         __be16                  *tagp;          /* data entry tag pointer */
1707         xfs_trans_t             *tp;            /* transaction pointer */
1708         __be16                  *bests;
1709         struct xfs_dir3_icfree_hdr freehdr;
1710         struct xfs_dir2_data_free *bf;
1711
1712         dp = args->dp;
1713         mp = dp->i_mount;
1714         tp = args->trans;
1715         length = xfs_dir3_data_entsize(mp, args->namelen);
1716         /*
1717          * If we came in with a freespace block that means that lookup
1718          * found an entry with our hash value.  This is the freespace
1719          * block for that data entry.
1720          */
1721         if (fblk) {
1722                 fbp = fblk->bp;
1723                 /*
1724                  * Remember initial freespace block number.
1725                  */
1726                 ifbno = fblk->blkno;
1727                 free = fbp->b_addr;
1728                 findex = fblk->index;
1729                 bests = xfs_dir3_free_bests_p(mp, free);
1730                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1731
1732                 /*
1733                  * This means the free entry showed that the data block had
1734                  * space for our entry, so we remembered it.
1735                  * Use that data block.
1736                  */
1737                 if (findex >= 0) {
1738                         ASSERT(findex < freehdr.nvalid);
1739                         ASSERT(be16_to_cpu(bests[findex]) != NULLDATAOFF);
1740                         ASSERT(be16_to_cpu(bests[findex]) >= length);
1741                         dbno = freehdr.firstdb + findex;
1742                 } else {
1743                         /*
1744                          * The data block looked at didn't have enough room.
1745                          * We'll start at the beginning of the freespace entries.
1746                          */
1747                         dbno = -1;
1748                         findex = 0;
1749                 }
1750         } else {
1751                 /*
1752                  * Didn't come in with a freespace block, so no data block.
1753                  */
1754                 ifbno = dbno = -1;
1755                 fbp = NULL;
1756                 findex = 0;
1757         }
1758
1759         /*
1760          * If we don't have a data block yet, we're going to scan the
1761          * freespace blocks looking for one.  Figure out what the
1762          * highest freespace block number is.
1763          */
1764         if (dbno == -1) {
1765                 xfs_fileoff_t   fo;             /* freespace block number */
1766
1767                 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1768                         return error;
1769                 lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1770                 fbno = ifbno;
1771         }
1772         /*
1773          * While we haven't identified a data block, search the freeblock
1774          * data for a good data block.  If we find a null freeblock entry,
1775          * indicating a hole in the data blocks, remember that.
1776          */
1777         while (dbno == -1) {
1778                 /*
1779                  * If we don't have a freeblock in hand, get the next one.
1780                  */
1781                 if (fbp == NULL) {
1782                         /*
1783                          * Happens the first time through unless lookup gave
1784                          * us a freespace block to start with.
1785                          */
1786                         if (++fbno == 0)
1787                                 fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1788                         /*
1789                          * If it's ifbno we already looked at it.
1790                          */
1791                         if (fbno == ifbno)
1792                                 fbno++;
1793                         /*
1794                          * If it's off the end we're done.
1795                          */
1796                         if (fbno >= lastfbno)
1797                                 break;
1798                         /*
1799                          * Read the block.  There can be holes in the
1800                          * freespace blocks, so this might not succeed.
1801                          * This should be really rare, so there's no reason
1802                          * to avoid it.
1803                          */
1804                         error = xfs_dir2_free_try_read(tp, dp,
1805                                                 xfs_dir2_db_to_da(mp, fbno),
1806                                                 &fbp);
1807                         if (error)
1808                                 return error;
1809                         if (!fbp)
1810                                 continue;
1811                         free = fbp->b_addr;
1812                         findex = 0;
1813                 }
1814                 /*
1815                  * Look at the current free entry.  Is it good enough?
1816                  *
1817                  * The bests initialisation should be where the bufer is read in
1818                  * the above branch. But gcc is too stupid to realise that bests
1819                  * and the freehdr are actually initialised if they are placed
1820                  * there, so we have to do it here to avoid warnings. Blech.
1821                  */
1822                 bests = xfs_dir3_free_bests_p(mp, free);
1823                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1824                 if (be16_to_cpu(bests[findex]) != NULLDATAOFF &&
1825                     be16_to_cpu(bests[findex]) >= length)
1826                         dbno = freehdr.firstdb + findex;
1827                 else {
1828                         /*
1829                          * Are we done with the freeblock?
1830                          */
1831                         if (++findex == freehdr.nvalid) {
1832                                 /*
1833                                  * Drop the block.
1834                                  */
1835                                 xfs_trans_brelse(tp, fbp);
1836                                 fbp = NULL;
1837                                 if (fblk && fblk->bp)
1838                                         fblk->bp = NULL;
1839                         }
1840                 }
1841         }
1842         /*
1843          * If we don't have a data block, we need to allocate one and make
1844          * the freespace entries refer to it.
1845          */
1846         if (unlikely(dbno == -1)) {
1847                 /*
1848                  * Not allowed to allocate, return failure.
1849                  */
1850                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
1851                         return XFS_ERROR(ENOSPC);
1852
1853                 /*
1854                  * Allocate and initialize the new data block.
1855                  */
1856                 if (unlikely((error = xfs_dir2_grow_inode(args,
1857                                                          XFS_DIR2_DATA_SPACE,
1858                                                          &dbno)) ||
1859                     (error = xfs_dir3_data_init(args, dbno, &dbp))))
1860                         return error;
1861
1862                 /*
1863                  * If (somehow) we have a freespace block, get rid of it.
1864                  */
1865                 if (fbp)
1866                         xfs_trans_brelse(tp, fbp);
1867                 if (fblk && fblk->bp)
1868                         fblk->bp = NULL;
1869
1870                 /*
1871                  * Get the freespace block corresponding to the data block
1872                  * that was just allocated.
1873                  */
1874                 fbno = xfs_dir2_db_to_fdb(mp, dbno);
1875                 error = xfs_dir2_free_try_read(tp, dp,
1876                                                xfs_dir2_db_to_da(mp, fbno),
1877                                                &fbp);
1878                 if (error)
1879                         return error;
1880
1881                 /*
1882                  * If there wasn't a freespace block, the read will
1883                  * return a NULL fbp.  Allocate and initialize a new one.
1884                  */
1885                 if (!fbp) {
1886                         error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1887                                                     &fbno);
1888                         if (error)
1889                                 return error;
1890
1891                         if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1892                                 xfs_alert(mp,
1893                         "%s: dir ino %llu needed freesp block %lld for\n"
1894                         "  data block %lld, got %lld ifbno %llu lastfbno %d",
1895                                         __func__, (unsigned long long)dp->i_ino,
1896                                         (long long)xfs_dir2_db_to_fdb(mp, dbno),
1897                                         (long long)dbno, (long long)fbno,
1898                                         (unsigned long long)ifbno, lastfbno);
1899                                 if (fblk) {
1900                                         xfs_alert(mp,
1901                                 " fblk 0x%p blkno %llu index %d magic 0x%x",
1902                                                 fblk,
1903                                                 (unsigned long long)fblk->blkno,
1904                                                 fblk->index,
1905                                                 fblk->magic);
1906                                 } else {
1907                                         xfs_alert(mp, " ... fblk is NULL");
1908                                 }
1909                                 XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1910                                                  XFS_ERRLEVEL_LOW, mp);
1911                                 return XFS_ERROR(EFSCORRUPTED);
1912                         }
1913
1914                         /*
1915                          * Get a buffer for the new block.
1916                          */
1917                         error = xfs_dir3_free_get_buf(tp, dp, fbno, &fbp);
1918                         if (error)
1919                                 return error;
1920                         free = fbp->b_addr;
1921                         bests = xfs_dir3_free_bests_p(mp, free);
1922                         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1923
1924                         /*
1925                          * Remember the first slot as our empty slot.
1926                          */
1927                         freehdr.firstdb = (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1928                                         xfs_dir3_free_max_bests(mp);
1929                 } else {
1930                         free = fbp->b_addr;
1931                         bests = xfs_dir3_free_bests_p(mp, free);
1932                         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1933                 }
1934
1935                 /*
1936                  * Set the freespace block index from the data block number.
1937                  */
1938                 findex = xfs_dir2_db_to_fdindex(mp, dbno);
1939                 /*
1940                  * If it's after the end of the current entries in the
1941                  * freespace block, extend that table.
1942                  */
1943                 if (findex >= freehdr.nvalid) {
1944                         ASSERT(findex < xfs_dir3_free_max_bests(mp));
1945                         freehdr.nvalid = findex + 1;
1946                         /*
1947                          * Tag new entry so nused will go up.
1948                          */
1949                         bests[findex] = cpu_to_be16(NULLDATAOFF);
1950                 }
1951                 /*
1952                  * If this entry was for an empty data block
1953                  * (this should always be true) then update the header.
1954                  */
1955                 if (bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1956                         freehdr.nused++;
1957                         xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
1958                         xfs_dir2_free_log_header(tp, fbp);
1959                 }
1960                 /*
1961                  * Update the real value in the table.
1962                  * We haven't allocated the data entry yet so this will
1963                  * change again.
1964                  */
1965                 hdr = dbp->b_addr;
1966                 bf = xfs_dir3_data_bestfree_p(hdr);
1967                 bests[findex] = bf[0].length;
1968                 logfree = 1;
1969         }
1970         /*
1971          * We had a data block so we don't have to make a new one.
1972          */
1973         else {
1974                 /*
1975                  * If just checking, we succeeded.
1976                  */
1977                 if (args->op_flags & XFS_DA_OP_JUSTCHECK)
1978                         return 0;
1979
1980                 /*
1981                  * Read the data block in.
1982                  */
1983                 error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1984                                            -1, &dbp);
1985                 if (error)
1986                         return error;
1987                 hdr = dbp->b_addr;
1988                 bf = xfs_dir3_data_bestfree_p(hdr);
1989                 logfree = 0;
1990         }
1991         ASSERT(be16_to_cpu(bf[0].length) >= length);
1992         /*
1993          * Point to the existing unused space.
1994          */
1995         dup = (xfs_dir2_data_unused_t *)
1996               ((char *)hdr + be16_to_cpu(bf[0].offset));
1997         needscan = needlog = 0;
1998         /*
1999          * Mark the first part of the unused space, inuse for us.
2000          */
2001         xfs_dir2_data_use_free(tp, dbp, dup,
2002                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
2003                 &needlog, &needscan);
2004         /*
2005          * Fill in the new entry and log it.
2006          */
2007         dep = (xfs_dir2_data_entry_t *)dup;
2008         dep->inumber = cpu_to_be64(args->inumber);
2009         dep->namelen = args->namelen;
2010         memcpy(dep->name, args->name, dep->namelen);
2011         xfs_dir3_dirent_put_ftype(mp, dep, args->filetype);
2012         tagp = xfs_dir3_data_entry_tag_p(mp, dep);
2013         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
2014         xfs_dir2_data_log_entry(tp, dbp, dep);
2015         /*
2016          * Rescan the block for bestfree if needed.
2017          */
2018         if (needscan)
2019                 xfs_dir2_data_freescan(mp, hdr, &needlog);
2020         /*
2021          * Log the data block header if needed.
2022          */
2023         if (needlog)
2024                 xfs_dir2_data_log_header(tp, dbp);
2025         /*
2026          * If the freespace entry is now wrong, update it.
2027          */
2028         bests = xfs_dir3_free_bests_p(mp, free); /* gcc is so stupid */
2029         if (be16_to_cpu(bests[findex]) != be16_to_cpu(bf[0].length)) {
2030                 bests[findex] = bf[0].length;
2031                 logfree = 1;
2032         }
2033         /*
2034          * Log the freespace entry if needed.
2035          */
2036         if (logfree)
2037                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
2038         /*
2039          * Return the data block and offset in args, then drop the data block.
2040          */
2041         args->blkno = (xfs_dablk_t)dbno;
2042         args->index = be16_to_cpu(*tagp);
2043         return 0;
2044 }
2045
2046 /*
2047  * Lookup an entry in a node-format directory.
2048  * All the real work happens in xfs_da3_node_lookup_int.
2049  * The only real output is the inode number of the entry.
2050  */
2051 int                                             /* error */
2052 xfs_dir2_node_lookup(
2053         xfs_da_args_t   *args)                  /* operation arguments */
2054 {
2055         int             error;                  /* error return value */
2056         int             i;                      /* btree level */
2057         int             rval;                   /* operation return value */
2058         xfs_da_state_t  *state;                 /* btree cursor */
2059
2060         trace_xfs_dir2_node_lookup(args);
2061
2062         /*
2063          * Allocate and initialize the btree cursor.
2064          */
2065         state = xfs_da_state_alloc();
2066         state->args = args;
2067         state->mp = args->dp->i_mount;
2068         state->blocksize = state->mp->m_dirblksize;
2069         state->node_ents = state->mp->m_dir_node_ents;
2070         /*
2071          * Fill in the path to the entry in the cursor.
2072          */
2073         error = xfs_da3_node_lookup_int(state, &rval);
2074         if (error)
2075                 rval = error;
2076         else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
2077                 /* If a CI match, dup the actual name and return EEXIST */
2078                 xfs_dir2_data_entry_t   *dep;
2079
2080                 dep = (xfs_dir2_data_entry_t *)
2081                         ((char *)state->extrablk.bp->b_addr +
2082                                                  state->extrablk.index);
2083                 rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
2084         }
2085         /*
2086          * Release the btree blocks and leaf block.
2087          */
2088         for (i = 0; i < state->path.active; i++) {
2089                 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2090                 state->path.blk[i].bp = NULL;
2091         }
2092         /*
2093          * Release the data block if we have it.
2094          */
2095         if (state->extravalid && state->extrablk.bp) {
2096                 xfs_trans_brelse(args->trans, state->extrablk.bp);
2097                 state->extrablk.bp = NULL;
2098         }
2099         xfs_da_state_free(state);
2100         return rval;
2101 }
2102
2103 /*
2104  * Remove an entry from a node-format directory.
2105  */
2106 int                                             /* error */
2107 xfs_dir2_node_removename(
2108         xfs_da_args_t           *args)          /* operation arguments */
2109 {
2110         xfs_da_state_blk_t      *blk;           /* leaf block */
2111         int                     error;          /* error return value */
2112         int                     rval;           /* operation return value */
2113         xfs_da_state_t          *state;         /* btree cursor */
2114
2115         trace_xfs_dir2_node_removename(args);
2116
2117         /*
2118          * Allocate and initialize the btree cursor.
2119          */
2120         state = xfs_da_state_alloc();
2121         state->args = args;
2122         state->mp = args->dp->i_mount;
2123         state->blocksize = state->mp->m_dirblksize;
2124         state->node_ents = state->mp->m_dir_node_ents;
2125         /*
2126          * Look up the entry we're deleting, set up the cursor.
2127          */
2128         error = xfs_da3_node_lookup_int(state, &rval);
2129         if (error)
2130                 rval = error;
2131         /*
2132          * Didn't find it, upper layer screwed up.
2133          */
2134         if (rval != EEXIST) {
2135                 xfs_da_state_free(state);
2136                 return rval;
2137         }
2138         blk = &state->path.blk[state->path.active - 1];
2139         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2140         ASSERT(state->extravalid);
2141         /*
2142          * Remove the leaf and data entries.
2143          * Extrablk refers to the data block.
2144          */
2145         error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
2146                 &state->extrablk, &rval);
2147         if (error)
2148                 return error;
2149         /*
2150          * Fix the hash values up the btree.
2151          */
2152         xfs_da3_fixhashpath(state, &state->path);
2153         /*
2154          * If we need to join leaf blocks, do it.
2155          */
2156         if (rval && state->path.active > 1)
2157                 error = xfs_da3_join(state);
2158         /*
2159          * If no errors so far, try conversion to leaf format.
2160          */
2161         if (!error)
2162                 error = xfs_dir2_node_to_leaf(state);
2163         xfs_da_state_free(state);
2164         return error;
2165 }
2166
2167 /*
2168  * Replace an entry's inode number in a node-format directory.
2169  */
2170 int                                             /* error */
2171 xfs_dir2_node_replace(
2172         xfs_da_args_t           *args)          /* operation arguments */
2173 {
2174         xfs_da_state_blk_t      *blk;           /* leaf block */
2175         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
2176         xfs_dir2_data_entry_t   *dep;           /* data entry changed */
2177         int                     error;          /* error return value */
2178         int                     i;              /* btree level */
2179         xfs_ino_t               inum;           /* new inode number */
2180         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2181         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
2182         int                     rval;           /* internal return value */
2183         xfs_da_state_t          *state;         /* btree cursor */
2184
2185         trace_xfs_dir2_node_replace(args);
2186
2187         /*
2188          * Allocate and initialize the btree cursor.
2189          */
2190         state = xfs_da_state_alloc();
2191         state->args = args;
2192         state->mp = args->dp->i_mount;
2193         state->blocksize = state->mp->m_dirblksize;
2194         state->node_ents = state->mp->m_dir_node_ents;
2195         inum = args->inumber;
2196         /*
2197          * Lookup the entry to change in the btree.
2198          */
2199         error = xfs_da3_node_lookup_int(state, &rval);
2200         if (error) {
2201                 rval = error;
2202         }
2203         /*
2204          * It should be found, since the vnodeops layer has looked it up
2205          * and locked it.  But paranoia is good.
2206          */
2207         if (rval == EEXIST) {
2208                 struct xfs_dir2_leaf_entry *ents;
2209                 /*
2210                  * Find the leaf entry.
2211                  */
2212                 blk = &state->path.blk[state->path.active - 1];
2213                 ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2214                 leaf = blk->bp->b_addr;
2215                 ents = xfs_dir3_leaf_ents_p(leaf);
2216                 lep = &ents[blk->index];
2217                 ASSERT(state->extravalid);
2218                 /*
2219                  * Point to the data entry.
2220                  */
2221                 hdr = state->extrablk.bp->b_addr;
2222                 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
2223                        hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
2224                 dep = (xfs_dir2_data_entry_t *)
2225                       ((char *)hdr +
2226                        xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
2227                 ASSERT(inum != be64_to_cpu(dep->inumber));
2228                 /*
2229                  * Fill in the new inode number and log the entry.
2230                  */
2231                 dep->inumber = cpu_to_be64(inum);
2232                 xfs_dir3_dirent_put_ftype(state->mp, dep, args->filetype);
2233                 xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
2234                 rval = 0;
2235         }
2236         /*
2237          * Didn't find it, and we're holding a data block.  Drop it.
2238          */
2239         else if (state->extravalid) {
2240                 xfs_trans_brelse(args->trans, state->extrablk.bp);
2241                 state->extrablk.bp = NULL;
2242         }
2243         /*
2244          * Release all the buffers in the cursor.
2245          */
2246         for (i = 0; i < state->path.active; i++) {
2247                 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2248                 state->path.blk[i].bp = NULL;
2249         }
2250         xfs_da_state_free(state);
2251         return rval;
2252 }
2253
2254 /*
2255  * Trim off a trailing empty freespace block.
2256  * Return (in rvalp) 1 if we did it, 0 if not.
2257  */
2258 int                                             /* error */
2259 xfs_dir2_node_trim_free(
2260         xfs_da_args_t           *args,          /* operation arguments */
2261         xfs_fileoff_t           fo,             /* free block number */
2262         int                     *rvalp)         /* out: did something */
2263 {
2264         struct xfs_buf          *bp;            /* freespace buffer */
2265         xfs_inode_t             *dp;            /* incore directory inode */
2266         int                     error;          /* error return code */
2267         xfs_dir2_free_t         *free;          /* freespace structure */
2268         xfs_mount_t             *mp;            /* filesystem mount point */
2269         xfs_trans_t             *tp;            /* transaction pointer */
2270         struct xfs_dir3_icfree_hdr freehdr;
2271
2272         dp = args->dp;
2273         mp = dp->i_mount;
2274         tp = args->trans;
2275         /*
2276          * Read the freespace block.
2277          */
2278         error = xfs_dir2_free_try_read(tp, dp, fo, &bp);
2279         if (error)
2280                 return error;
2281         /*
2282          * There can be holes in freespace.  If fo is a hole, there's
2283          * nothing to do.
2284          */
2285         if (!bp)
2286                 return 0;
2287         free = bp->b_addr;
2288         xfs_dir3_free_hdr_from_disk(&freehdr, free);
2289
2290         /*
2291          * If there are used entries, there's nothing to do.
2292          */
2293         if (freehdr.nused > 0) {
2294                 xfs_trans_brelse(tp, bp);
2295                 *rvalp = 0;
2296                 return 0;
2297         }
2298         /*
2299          * Blow the block away.
2300          */
2301         if ((error =
2302             xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
2303                     bp))) {
2304                 /*
2305                  * Can't fail with ENOSPC since that only happens with no
2306                  * space reservation, when breaking up an extent into two
2307                  * pieces.  This is the last block of an extent.
2308                  */
2309                 ASSERT(error != ENOSPC);
2310                 xfs_trans_brelse(tp, bp);
2311                 return error;
2312         }
2313         /*
2314          * Return that we succeeded.
2315          */
2316         *rvalp = 1;
2317         return 0;
2318 }