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         xfs_dir2_free_t         *free;          /* freespace structure */
 317
 318         free = bp->b_addr;
 319         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 320                free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 321         xfs_trans_log_buf(tp, bp, 0, xfs_dir3_free_hdr_size(tp->t_mountp) - 1);
 322 }
 323
 324 /*
 325  * Convert a leaf-format directory to a node-format directory.
 326  * We need to change the magic number of the leaf block, and copy
 327  * the freespace table out of the leaf block into its own block.
 328  */
 329 int                                             /* error */
 330 xfs_dir2_leaf_to_node(
 331         xfs_da_args_t           *args,          /* operation arguments */
 332         struct xfs_buf          *lbp)           /* leaf buffer */
 333 {
 334         xfs_inode_t             *dp;            /* incore directory inode */
 335         int                     error;          /* error return value */
 336         struct xfs_buf          *fbp;           /* freespace buffer */
 337         xfs_dir2_db_t           fdb;            /* freespace block number */
 338         xfs_dir2_free_t         *free;          /* freespace structure */
 339         __be16                  *from;          /* pointer to freespace entry */
 340         int                     i;              /* leaf freespace index */
 341         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 342         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 343         xfs_mount_t             *mp;            /* filesystem mount point */
 344         int                     n;              /* count of live freespc ents */
 345         xfs_dir2_data_off_t     off;            /* freespace entry value */
 346         __be16                  *to;            /* pointer to freespace entry */
 347         xfs_trans_t             *tp;            /* transaction pointer */
 348         struct xfs_dir3_icfree_hdr freehdr;
 349
 350         trace_xfs_dir2_leaf_to_node(args);
 351
 352         dp = args->dp;
 353         mp = dp->i_mount;
 354         tp = args->trans;
 355         /*
 356          * Add a freespace block to the directory.
 357          */
 358         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 359                 return error;
 360         }
 361         ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 362         /*
 363          * Get the buffer for the new freespace block.
 364          */
 365         error = xfs_dir3_free_get_buf(tp, dp, fdb, &fbp);
 366         if (error)
 367                 return error;
 368
 369         free = fbp->b_addr;
 370         xfs_dir3_free_hdr_from_disk(&freehdr, free);
 371         leaf = lbp->b_addr;
 372         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 373         ASSERT(be32_to_cpu(ltp->bestcount) <=
 374                                 (uint)dp->i_d.di_size / mp->m_dirblksize);
 375
 376         /*
 377          * Copy freespace entries from the leaf block to the new block.
 378          * Count active entries.
 379          */
 380         from = xfs_dir2_leaf_bests_p(ltp);
 381         to = xfs_dir3_free_bests_p(mp, free);
 382         for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 383                 if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 384                         n++;
 385                 *to = cpu_to_be16(off);
 386         }
 387
 388         /*
 389          * Now initialize the freespace block header.
 390          */
 391         freehdr.nused = n;
 392         freehdr.nvalid = be32_to_cpu(ltp->bestcount);
 393
 394         xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
 395         xfs_dir2_free_log_bests(tp, fbp, 0, freehdr.nvalid - 1);
 396         xfs_dir2_free_log_header(tp, fbp);
 397
 398         /*
 399          * Converting the leaf to a leafnode is just a matter of changing the
 400          * magic number and the ops. Do the change directly to the buffer as
 401          * it's less work (and less code) than decoding the header to host
 402          * format and back again.
 403          */
 404         if (leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC))
 405                 leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 406         else
 407                 leaf->hdr.info.magic = cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 408         lbp->b_ops = &xfs_dir3_leafn_buf_ops;
 409         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAFN_BUF);
 410         xfs_dir3_leaf_log_header(tp, lbp);
 411         xfs_dir3_leaf_check(mp, lbp);
 412         return 0;
 413 }
 414
 415 /*
 416  * Add a leaf entry to a leaf block in a node-form directory.
 417  * The other work necessary is done from the caller.
 418  */
 419 static int                                      /* error */
 420 xfs_dir2_leafn_add(
 421         struct xfs_buf          *bp,            /* leaf buffer */
 422         xfs_da_args_t           *args,          /* operation arguments */
 423         int                     index)          /* insertion pt for new entry */
 424 {
 425         int                     compact;        /* compacting stale leaves */
 426         xfs_inode_t             *dp;            /* incore directory inode */
 427         int                     highstale;      /* next stale entry */
 428         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 429         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 430         int                     lfloghigh;      /* high leaf entry logging */
 431         int                     lfloglow;       /* low leaf entry logging */
 432         int                     lowstale;       /* previous stale entry */
 433         xfs_mount_t             *mp;            /* filesystem mount point */
 434         xfs_trans_t             *tp;            /* transaction pointer */
 435         struct xfs_dir3_icleaf_hdr leafhdr;
 436         struct xfs_dir2_leaf_entry *ents;
 437
 438         trace_xfs_dir2_leafn_add(args, index);
 439
 440         dp = args->dp;
 441         mp = dp->i_mount;
 442         tp = args->trans;
 443         leaf = bp->b_addr;
 444         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 445         ents = xfs_dir3_leaf_ents_p(leaf);
 446
 447         /*
 448          * Quick check just to make sure we are not going to index
 449          * into other peoples memory
 450          */
 451         if (index < 0)
 452                 return XFS_ERROR(EFSCORRUPTED);
 453
 454         /*
 455          * If there are already the maximum number of leaf entries in
 456          * the block, if there are no stale entries it won't fit.
 457          * Caller will do a split.  If there are stale entries we'll do
 458          * a compact.
 459          */
 460
 461         if (leafhdr.count == xfs_dir3_max_leaf_ents(mp, leaf)) {
 462                 if (!leafhdr.stale)
 463                         return XFS_ERROR(ENOSPC);
 464                 compact = leafhdr.stale > 1;
 465         } else
 466                 compact = 0;
 467         ASSERT(index == 0 || be32_to_cpu(ents[index - 1].hashval) <= args->hashval);
 468         ASSERT(index == leafhdr.count ||
 469                be32_to_cpu(ents[index].hashval) >= args->hashval);
 470
 471         if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 472                 return 0;
 473
 474         /*
 475          * Compact out all but one stale leaf entry.  Leaves behind
 476          * the entry closest to index.
 477          */
 478         if (compact)
 479                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 480                                          &highstale, &lfloglow, &lfloghigh);
 481         else if (leafhdr.stale) {
 482                 /*
 483                  * Set impossible logging indices for this case.
 484                  */
 485                 lfloglow = leafhdr.count;
 486                 lfloghigh = -1;
 487         }
 488
 489         /*
 490          * Insert the new entry, log everything.
 491          */
 492         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 493                                        highstale, &lfloglow, &lfloghigh);
 494
 495         lep->hashval = cpu_to_be32(args->hashval);
 496         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
 497                                 args->blkno, args->index));
 498
 499         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
 500         xfs_dir3_leaf_log_header(tp, bp);
 501         xfs_dir3_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 502         xfs_dir3_leaf_check(mp, bp);
 503         return 0;
 504 }
 505
 506 #ifdef DEBUG
 507 static void
 508 xfs_dir2_free_hdr_check(
 509         struct xfs_mount *mp,
 510         struct xfs_buf  *bp,
 511         xfs_dir2_db_t   db)
 512 {
 513         struct xfs_dir3_icfree_hdr hdr;
 514
 515         xfs_dir3_free_hdr_from_disk(&hdr, bp->b_addr);
 516
 517         ASSERT((hdr.firstdb % xfs_dir3_free_max_bests(mp)) == 0);
 518         ASSERT(hdr.firstdb <= db);
 519         ASSERT(db < hdr.firstdb + hdr.nvalid);
 520 }
 521 #else
 522 #define xfs_dir2_free_hdr_check(mp, dp, db)
 523 #endif  /* DEBUG */
 524
 525 /*
 526  * Return the last hash value in the leaf.
 527  * Stale entries are ok.
 528  */
 529 xfs_dahash_t                                    /* hash value */
 530 xfs_dir2_leafn_lasthash(
 531         struct xfs_buf  *bp,                    /* leaf buffer */
 532         int             *count)                 /* count of entries in leaf */
 533 {
 534         struct xfs_dir2_leaf    *leaf = bp->b_addr;
 535         struct xfs_dir2_leaf_entry *ents;
 536         struct xfs_dir3_icleaf_hdr leafhdr;
 537
 538         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 539
 540         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
 541                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
 542
 543         if (count)
 544                 *count = leafhdr.count;
 545         if (!leafhdr.count)
 546                 return 0;
 547
 548         ents = xfs_dir3_leaf_ents_p(leaf);
 549         return be32_to_cpu(ents[leafhdr.count - 1].hashval);
 550 }
 551
 552 /*
 553  * Look up a leaf entry for space to add a name in a node-format leaf block.
 554  * The extrablk in state is a freespace block.
 555  */
 556 STATIC int
 557 xfs_dir2_leafn_lookup_for_addname(
 558         struct xfs_buf          *bp,            /* leaf buffer */
 559         xfs_da_args_t           *args,          /* operation arguments */
 560         int                     *indexp,        /* out: leaf entry index */
 561         xfs_da_state_t          *state)         /* state to fill in */
 562 {
 563         struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 564         xfs_dir2_db_t           curdb = -1;     /* current data block number */
 565         xfs_dir2_db_t           curfdb = -1;    /* current free block number */
 566         xfs_inode_t             *dp;            /* incore directory inode */
 567         int                     error;          /* error return value */
 568         int                     fi;             /* free entry index */
 569         xfs_dir2_free_t         *free = NULL;   /* free block structure */
 570         int                     index;          /* leaf entry index */
 571         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 572         int                     length;         /* length of new data entry */
 573         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 574         xfs_mount_t             *mp;            /* filesystem mount point */
 575         xfs_dir2_db_t           newdb;          /* new data block number */
 576         xfs_dir2_db_t           newfdb;         /* new free block number */
 577         xfs_trans_t             *tp;            /* transaction pointer */
 578         struct xfs_dir2_leaf_entry *ents;
 579         struct xfs_dir3_icleaf_hdr leafhdr;
 580
 581         dp = args->dp;
 582         tp = args->trans;
 583         mp = dp->i_mount;
 584         leaf = bp->b_addr;
 585         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 586         ents = xfs_dir3_leaf_ents_p(leaf);
 587
 588         xfs_dir3_leaf_check(mp, bp);
 589         ASSERT(leafhdr.count > 0);
 590
 591         /*
 592          * Look up the hash value in the leaf entries.
 593          */
 594         index = xfs_dir2_leaf_search_hash(args, bp);
 595         /*
 596          * Do we have a buffer coming in?
 597          */
 598         if (state->extravalid) {
 599                 /* If so, it's a free block buffer, get the block number. */
 600                 curbp = state->extrablk.bp;
 601                 curfdb = state->extrablk.blkno;
 602                 free = curbp->b_addr;
 603                 ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 604                        free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 605         }
 606         length = xfs_dir2_data_entsize(args->namelen);
 607         /*
 608          * Loop over leaf entries with the right hash value.
 609          */
 610         for (lep = &ents[index];
 611              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 612              lep++, index++) {
 613                 /*
 614                  * Skip stale leaf entries.
 615                  */
 616                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 617                         continue;
 618                 /*
 619                  * Pull the data block number from the entry.
 620                  */
 621                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 622                 /*
 623                  * For addname, we're looking for a place to put the new entry.
 624                  * We want to use a data block with an entry of equal
 625                  * hash value to ours if there is one with room.
 626                  *
 627                  * If this block isn't the data block we already have
 628                  * in hand, take a look at it.
 629                  */
 630                 if (newdb != curdb) {
 631                         __be16 *bests;
 632
 633                         curdb = newdb;
 634                         /*
 635                          * Convert the data block to the free block
 636                          * holding its freespace information.
 637                          */
 638                         newfdb = xfs_dir2_db_to_fdb(mp, newdb);
 639                         /*
 640                          * If it's not the one we have in hand, read it in.
 641                          */
 642                         if (newfdb != curfdb) {
 643                                 /*
 644                                  * If we had one before, drop it.
 645                                  */
 646                                 if (curbp)
 647                                         xfs_trans_brelse(tp, curbp);
 648
 649                                 error = xfs_dir2_free_read(tp, dp,
 650                                                 xfs_dir2_db_to_da(mp, newfdb),
 651                                                 &curbp);
 652                                 if (error)
 653                                         return error;
 654                                 free = curbp->b_addr;
 655
 656                                 xfs_dir2_free_hdr_check(mp, curbp, curdb);
 657                         }
 658                         /*
 659                          * Get the index for our entry.
 660                          */
 661                         fi = xfs_dir2_db_to_fdindex(mp, curdb);
 662                         /*
 663                          * If it has room, return it.
 664                          */
 665                         bests = xfs_dir3_free_bests_p(mp, free);
 666                         if (unlikely(bests[fi] == cpu_to_be16(NULLDATAOFF))) {
 667                                 XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 668                                                         XFS_ERRLEVEL_LOW, mp);
 669                                 if (curfdb != newfdb)
 670                                         xfs_trans_brelse(tp, curbp);
 671                                 return XFS_ERROR(EFSCORRUPTED);
 672                         }
 673                         curfdb = newfdb;
 674                         if (be16_to_cpu(bests[fi]) >= length)
 675                                 goto out;
 676                 }
 677         }
 678         /* Didn't find any space */
 679         fi = -1;
 680 out:
 681         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 682         if (curbp) {
 683                 /* Giving back a free block. */
 684                 state->extravalid = 1;
 685                 state->extrablk.bp = curbp;
 686                 state->extrablk.index = fi;
 687                 state->extrablk.blkno = curfdb;
 688
 689                 /*
 690                  * Important: this magic number is not in the buffer - it's for
 691                  * buffer type information and therefore only the free/data type
 692                  * matters here, not whether CRCs are enabled or not.
 693                  */
 694                 state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 695         } else {
 696                 state->extravalid = 0;
 697         }
 698         /*
 699          * Return the index, that will be the insertion point.
 700          */
 701         *indexp = index;
 702         return XFS_ERROR(ENOENT);
 703 }
 704
 705 /*
 706  * Look up a leaf entry in a node-format leaf block.
 707  * The extrablk in state a data block.
 708  */
 709 STATIC int
 710 xfs_dir2_leafn_lookup_for_entry(
 711         struct xfs_buf          *bp,            /* leaf buffer */
 712         xfs_da_args_t           *args,          /* operation arguments */
 713         int                     *indexp,        /* out: leaf entry index */
 714         xfs_da_state_t          *state)         /* state to fill in */
 715 {
 716         struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 717         xfs_dir2_db_t           curdb = -1;     /* current data block number */
 718         xfs_dir2_data_entry_t   *dep;           /* data block entry */
 719         xfs_inode_t             *dp;            /* incore directory inode */
 720         int                     error;          /* error return value */
 721         int                     index;          /* leaf entry index */
 722         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 723         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 724         xfs_mount_t             *mp;            /* filesystem mount point */
 725         xfs_dir2_db_t           newdb;          /* new data block number */
 726         xfs_trans_t             *tp;            /* transaction pointer */
 727         enum xfs_dacmp          cmp;            /* comparison result */
 728         struct xfs_dir2_leaf_entry *ents;
 729         struct xfs_dir3_icleaf_hdr leafhdr;
 730
 731         dp = args->dp;
 732         tp = args->trans;
 733         mp = dp->i_mount;
 734         leaf = bp->b_addr;
 735         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 736         ents = xfs_dir3_leaf_ents_p(leaf);
 737
 738         xfs_dir3_leaf_check(mp, bp);
 739         ASSERT(leafhdr.count > 0);
 740
 741         /*
 742          * Look up the hash value in the leaf entries.
 743          */
 744         index = xfs_dir2_leaf_search_hash(args, bp);
 745         /*
 746          * Do we have a buffer coming in?
 747          */
 748         if (state->extravalid) {
 749                 curbp = state->extrablk.bp;
 750                 curdb = state->extrablk.blkno;
 751         }
 752         /*
 753          * Loop over leaf entries with the right hash value.
 754          */
 755         for (lep = &ents[index];
 756              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 757              lep++, index++) {
 758                 /*
 759                  * Skip stale leaf entries.
 760                  */
 761                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 762                         continue;
 763                 /*
 764                  * Pull the data block number from the entry.
 765                  */
 766                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 767                 /*
 768                  * Not adding a new entry, so we really want to find
 769                  * the name given to us.
 770                  *
 771                  * If it's a different data block, go get it.
 772                  */
 773                 if (newdb != curdb) {
 774                         /*
 775                          * If we had a block before that we aren't saving
 776                          * for a CI name, drop it
 777                          */
 778                         if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 779                                                 curdb != state->extrablk.blkno))
 780                                 xfs_trans_brelse(tp, curbp);
 781                         /*
 782                          * If needing the block that is saved with a CI match,
 783                          * use it otherwise read in the new data block.
 784                          */
 785                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
 786                                         newdb == state->extrablk.blkno) {
 787                                 ASSERT(state->extravalid);
 788                                 curbp = state->extrablk.bp;
 789                         } else {
 790                                 error = xfs_dir3_data_read(tp, dp,
 791                                                 xfs_dir2_db_to_da(mp, newdb),
 792                                                 -1, &curbp);
 793                                 if (error)
 794                                         return error;
 795                         }
 796                         xfs_dir3_data_check(dp, curbp);
 797                         curdb = newdb;
 798                 }
 799                 /*
 800                  * Point to the data entry.
 801                  */
 802                 dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr +
 803                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
 804                 /*
 805                  * Compare the entry and if it's an exact match, return
 806                  * EEXIST immediately. If it's the first case-insensitive
 807                  * match, store the block & inode number and continue looking.
 808                  */
 809                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 810                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 811                         /* If there is a CI match block, drop it */
 812                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
 813                                                 curdb != state->extrablk.blkno)
 814                                 xfs_trans_brelse(tp, state->extrablk.bp);
 815                         args->cmpresult = cmp;
 816                         args->inumber = be64_to_cpu(dep->inumber);
 817                         *indexp = index;
 818                         state->extravalid = 1;
 819                         state->extrablk.bp = curbp;
 820                         state->extrablk.blkno = curdb;
 821                         state->extrablk.index = (int)((char *)dep -
 822                                                         (char *)curbp->b_addr);
 823                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 824                         curbp->b_ops = &xfs_dir3_data_buf_ops;
 825                         xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 826                         if (cmp == XFS_CMP_EXACT)
 827                                 return XFS_ERROR(EEXIST);
 828                 }
 829         }
 830         ASSERT(index == leafhdr.count || (args->op_flags & XFS_DA_OP_OKNOENT));
 831         if (curbp) {
 832                 if (args->cmpresult == XFS_CMP_DIFFERENT) {
 833                         /* Giving back last used data block. */
 834                         state->extravalid = 1;
 835                         state->extrablk.bp = curbp;
 836                         state->extrablk.index = -1;
 837                         state->extrablk.blkno = curdb;
 838                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 839                         curbp->b_ops = &xfs_dir3_data_buf_ops;
 840                         xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 841                 } else {
 842                         /* If the curbp is not the CI match block, drop it */
 843                         if (state->extrablk.bp != curbp)
 844                                 xfs_trans_brelse(tp, curbp);
 845                 }
 846         } else {
 847                 state->extravalid = 0;
 848         }
 849         *indexp = index;
 850         return XFS_ERROR(ENOENT);
 851 }
 852
 853 /*
 854  * Look up a leaf entry in a node-format leaf block.
 855  * If this is an addname then the extrablk in state is a freespace block,
 856  * otherwise it's a data block.
 857  */
 858 int
 859 xfs_dir2_leafn_lookup_int(
 860         struct xfs_buf          *bp,            /* leaf buffer */
 861         xfs_da_args_t           *args,          /* operation arguments */
 862         int                     *indexp,        /* out: leaf entry index */
 863         xfs_da_state_t          *state)         /* state to fill in */
 864 {
 865         if (args->op_flags & XFS_DA_OP_ADDNAME)
 866                 return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 867                                                         state);
 868         return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 869 }
 870
 871 /*
 872  * Move count leaf entries from source to destination leaf.
 873  * Log entries and headers.  Stale entries are preserved.
 874  */
 875 static void
 876 xfs_dir3_leafn_moveents(
 877         xfs_da_args_t                   *args,  /* operation arguments */
 878         struct xfs_buf                  *bp_s,  /* source */
 879         struct xfs_dir3_icleaf_hdr      *shdr,
 880         struct xfs_dir2_leaf_entry      *sents,
 881         int                             start_s,/* source leaf index */
 882         struct xfs_buf                  *bp_d,  /* destination */
 883         struct xfs_dir3_icleaf_hdr      *dhdr,
 884         struct xfs_dir2_leaf_entry      *dents,
 885         int                             start_d,/* destination leaf index */
 886         int                             count)  /* count of leaves to copy */
 887 {
 888         struct xfs_trans                *tp = args->trans;
 889         int                             stale;  /* count stale leaves copied */
 890
 891         trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 892
 893         /*
 894          * Silently return if nothing to do.
 895          */
 896         if (count == 0)
 897                 return;
 898
 899         /*
 900          * If the destination index is not the end of the current
 901          * destination leaf entries, open up a hole in the destination
 902          * to hold the new entries.
 903          */
 904         if (start_d < dhdr->count) {
 905                 memmove(&dents[start_d + count], &dents[start_d],
 906                         (dhdr->count - start_d) * sizeof(xfs_dir2_leaf_entry_t));
 907                 xfs_dir3_leaf_log_ents(tp, bp_d, start_d + count,
 908                                        count + dhdr->count - 1);
 909         }
 910         /*
 911          * If the source has stale leaves, count the ones in the copy range
 912          * so we can update the header correctly.
 913          */
 914         if (shdr->stale) {
 915                 int     i;                      /* temp leaf index */
 916
 917                 for (i = start_s, stale = 0; i < start_s + count; i++) {
 918                         if (sents[i].address ==
 919                                         cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 920                                 stale++;
 921                 }
 922         } else
 923                 stale = 0;
 924         /*
 925          * Copy the leaf entries from source to destination.
 926          */
 927         memcpy(&dents[start_d], &sents[start_s],
 928                 count * sizeof(xfs_dir2_leaf_entry_t));
 929         xfs_dir3_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 930
 931         /*
 932          * If there are source entries after the ones we copied,
 933          * delete the ones we copied by sliding the next ones down.
 934          */
 935         if (start_s + count < shdr->count) {
 936                 memmove(&sents[start_s], &sents[start_s + count],
 937                         count * sizeof(xfs_dir2_leaf_entry_t));
 938                 xfs_dir3_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 939         }
 940
 941         /*
 942          * Update the headers and log them.
 943          */
 944         shdr->count -= count;
 945         shdr->stale -= stale;
 946         dhdr->count += count;
 947         dhdr->stale += stale;
 948 }
 949
 950 /*
 951  * Determine the sort order of two leaf blocks.
 952  * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 953  */
 954 int                                             /* sort order */
 955 xfs_dir2_leafn_order(
 956         struct xfs_buf          *leaf1_bp,              /* leaf1 buffer */
 957         struct xfs_buf          *leaf2_bp)              /* leaf2 buffer */
 958 {
 959         struct xfs_dir2_leaf    *leaf1 = leaf1_bp->b_addr;
 960         struct xfs_dir2_leaf    *leaf2 = leaf2_bp->b_addr;
 961         struct xfs_dir2_leaf_entry *ents1;
 962         struct xfs_dir2_leaf_entry *ents2;
 963         struct xfs_dir3_icleaf_hdr hdr1;
 964         struct xfs_dir3_icleaf_hdr hdr2;
 965
 966         xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
 967         xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
 968         ents1 = xfs_dir3_leaf_ents_p(leaf1);
 969         ents2 = xfs_dir3_leaf_ents_p(leaf2);
 970
 971         if (hdr1.count > 0 && hdr2.count > 0 &&
 972             (be32_to_cpu(ents2[0].hashval) < be32_to_cpu(ents1[0].hashval) ||
 973              be32_to_cpu(ents2[hdr2.count - 1].hashval) <
 974                                 be32_to_cpu(ents1[hdr1.count - 1].hashval)))
 975                 return 1;
 976         return 0;
 977 }
 978
 979 /*
 980  * Rebalance leaf entries between two leaf blocks.
 981  * This is actually only called when the second block is new,
 982  * though the code deals with the general case.
 983  * A new entry will be inserted in one of the blocks, and that
 984  * entry is taken into account when balancing.
 985  */
 986 static void
 987 xfs_dir2_leafn_rebalance(
 988         xfs_da_state_t          *state,         /* btree cursor */
 989         xfs_da_state_blk_t      *blk1,          /* first btree block */
 990         xfs_da_state_blk_t      *blk2)          /* second btree block */
 991 {
 992         xfs_da_args_t           *args;          /* operation arguments */
 993         int                     count;          /* count (& direction) leaves */
 994         int                     isleft;         /* new goes in left leaf */
 995         xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 996         xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
 997         int                     mid;            /* midpoint leaf index */
 998 #if defined(DEBUG) || defined(XFS_WARN)
 999         int                     oldstale;       /* old count of stale leaves */
1000 #endif
1001         int                     oldsum;         /* old total leaf count */
1002         int                     swap;           /* swapped leaf blocks */
1003         struct xfs_dir2_leaf_entry *ents1;
1004         struct xfs_dir2_leaf_entry *ents2;
1005         struct xfs_dir3_icleaf_hdr hdr1;
1006         struct xfs_dir3_icleaf_hdr hdr2;
1007
1008         args = state->args;
1009         /*
1010          * If the block order is wrong, swap the arguments.
1011          */
1012         if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
1013                 xfs_da_state_blk_t      *tmp;   /* temp for block swap */
1014
1015                 tmp = blk1;
1016                 blk1 = blk2;
1017                 blk2 = tmp;
1018         }
1019         leaf1 = blk1->bp->b_addr;
1020         leaf2 = blk2->bp->b_addr;
1021         xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
1022         xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
1023         ents1 = xfs_dir3_leaf_ents_p(leaf1);
1024         ents2 = xfs_dir3_leaf_ents_p(leaf2);
1025
1026         oldsum = hdr1.count + hdr2.count;
1027 #if defined(DEBUG) || defined(XFS_WARN)
1028         oldstale = hdr1.stale + hdr2.stale;
1029 #endif
1030         mid = oldsum >> 1;
1031
1032         /*
1033          * If the old leaf count was odd then the new one will be even,
1034          * so we need to divide the new count evenly.
1035          */
1036         if (oldsum & 1) {
1037                 xfs_dahash_t    midhash;        /* middle entry hash value */
1038
1039                 if (mid >= hdr1.count)
1040                         midhash = be32_to_cpu(ents2[mid - hdr1.count].hashval);
1041                 else
1042                         midhash = be32_to_cpu(ents1[mid].hashval);
1043                 isleft = args->hashval <= midhash;
1044         }
1045         /*
1046          * If the old count is even then the new count is odd, so there's
1047          * no preferred side for the new entry.
1048          * Pick the left one.
1049          */
1050         else
1051                 isleft = 1;
1052         /*
1053          * Calculate moved entry count.  Positive means left-to-right,
1054          * negative means right-to-left.  Then move the entries.
1055          */
1056         count = hdr1.count - mid + (isleft == 0);
1057         if (count > 0)
1058                 xfs_dir3_leafn_moveents(args, blk1->bp, &hdr1, ents1,
1059                                         hdr1.count - count, blk2->bp,
1060                                         &hdr2, ents2, 0, count);
1061         else if (count < 0)
1062                 xfs_dir3_leafn_moveents(args, blk2->bp, &hdr2, ents2, 0,
1063                                         blk1->bp, &hdr1, ents1,
1064                                         hdr1.count, count);
1065
1066         ASSERT(hdr1.count + hdr2.count == oldsum);
1067         ASSERT(hdr1.stale + hdr2.stale == oldstale);
1068
1069         /* log the changes made when moving the entries */
1070         xfs_dir3_leaf_hdr_to_disk(leaf1, &hdr1);
1071         xfs_dir3_leaf_hdr_to_disk(leaf2, &hdr2);
1072         xfs_dir3_leaf_log_header(args->trans, blk1->bp);
1073         xfs_dir3_leaf_log_header(args->trans, blk2->bp);
1074
1075         xfs_dir3_leaf_check(args->dp->i_mount, blk1->bp);
1076         xfs_dir3_leaf_check(args->dp->i_mount, blk2->bp);
1077
1078         /*
1079          * Mark whether we're inserting into the old or new leaf.
1080          */
1081         if (hdr1.count < hdr2.count)
1082                 state->inleaf = swap;
1083         else if (hdr1.count > hdr2.count)
1084                 state->inleaf = !swap;
1085         else
1086                 state->inleaf = swap ^ (blk1->index <= hdr1.count);
1087         /*
1088          * Adjust the expected index for insertion.
1089          */
1090         if (!state->inleaf)
1091                 blk2->index = blk1->index - hdr1.count;
1092
1093         /*
1094          * Finally sanity check just to make sure we are not returning a
1095          * negative index
1096          */
1097         if(blk2->index < 0) {
1098                 state->inleaf = 1;
1099                 blk2->index = 0;
1100                 xfs_alert(args->dp->i_mount,
1101         "%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
1102                         __func__, blk1->index);
1103         }
1104 }
1105
1106 static int
1107 xfs_dir3_data_block_free(
1108         xfs_da_args_t           *args,
1109         struct xfs_dir2_data_hdr *hdr,
1110         struct xfs_dir2_free    *free,
1111         xfs_dir2_db_t           fdb,
1112         int                     findex,
1113         struct xfs_buf          *fbp,
1114         int                     longest)
1115 {
1116         struct xfs_trans        *tp = args->trans;
1117         int                     logfree = 0;
1118         __be16                  *bests;
1119         struct xfs_dir3_icfree_hdr freehdr;
1120
1121         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1122
1123         bests = xfs_dir3_free_bests_p(tp->t_mountp, free);
1124         if (hdr) {
1125                 /*
1126                  * Data block is not empty, just set the free entry to the new
1127                  * value.
1128                  */
1129                 bests[findex] = cpu_to_be16(longest);
1130                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1131                 return 0;
1132         }
1133
1134         /* One less used entry in the free table. */
1135         freehdr.nused--;
1136
1137         /*
1138          * If this was the last entry in the table, we can trim the table size
1139          * back.  There might be other entries at the end referring to
1140          * non-existent data blocks, get those too.
1141          */
1142         if (findex == freehdr.nvalid - 1) {
1143                 int     i;              /* free entry index */
1144
1145                 for (i = findex - 1; i >= 0; i--) {
1146                         if (bests[i] != cpu_to_be16(NULLDATAOFF))
1147                                 break;
1148                 }
1149                 freehdr.nvalid = i + 1;
1150                 logfree = 0;
1151         } else {
1152                 /* Not the last entry, just punch it out.  */
1153                 bests[findex] = cpu_to_be16(NULLDATAOFF);
1154                 logfree = 1;
1155         }
1156
1157         xfs_dir3_free_hdr_to_disk(free, &freehdr);
1158         xfs_dir2_free_log_header(tp, fbp);
1159
1160         /*
1161          * If there are no useful entries left in the block, get rid of the
1162          * block if we can.
1163          */
1164         if (!freehdr.nused) {
1165                 int error;
1166
1167                 error = xfs_dir2_shrink_inode(args, fdb, fbp);
1168                 if (error == 0) {
1169                         fbp = NULL;
1170                         logfree = 0;
1171                 } else if (error != ENOSPC || args->total != 0)
1172                         return error;
1173                 /*
1174                  * It's possible to get ENOSPC if there is no
1175                  * space reservation.  In this case some one
1176                  * else will eventually get rid of this block.
1177                  */
1178         }
1179
1180         /* Log the free entry that changed, unless we got rid of it.  */
1181         if (logfree)
1182                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1183         return 0;
1184 }
1185
1186 /*
1187  * Remove an entry from a node directory.
1188  * This removes the leaf entry and the data entry,
1189  * and updates the free block if necessary.
1190  */
1191 static int                                      /* error */
1192 xfs_dir2_leafn_remove(
1193         xfs_da_args_t           *args,          /* operation arguments */
1194         struct xfs_buf          *bp,            /* leaf buffer */
1195         int                     index,          /* leaf entry index */
1196         xfs_da_state_blk_t      *dblk,          /* data block */
1197         int                     *rval)          /* resulting block needs join */
1198 {
1199         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1200         xfs_dir2_db_t           db;             /* data block number */
1201         struct xfs_buf          *dbp;           /* data block buffer */
1202         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1203         xfs_inode_t             *dp;            /* incore directory inode */
1204         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1205         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1206         int                     longest;        /* longest data free entry */
1207         int                     off;            /* data block entry offset */
1208         xfs_mount_t             *mp;            /* filesystem mount point */
1209         int                     needlog;        /* need to log data header */
1210         int                     needscan;       /* need to rescan data frees */
1211         xfs_trans_t             *tp;            /* transaction pointer */
1212         struct xfs_dir2_data_free *bf;          /* bestfree table */
1213         struct xfs_dir3_icleaf_hdr leafhdr;
1214         struct xfs_dir2_leaf_entry *ents;
1215
1216         trace_xfs_dir2_leafn_remove(args, index);
1217
1218         dp = args->dp;
1219         tp = args->trans;
1220         mp = dp->i_mount;
1221         leaf = bp->b_addr;
1222         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1223         ents = xfs_dir3_leaf_ents_p(leaf);
1224
1225         /*
1226          * Point to the entry we're removing.
1227          */
1228         lep = &ents[index];
1229
1230         /*
1231          * Extract the data block and offset from the entry.
1232          */
1233         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1234         ASSERT(dblk->blkno == db);
1235         off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
1236         ASSERT(dblk->index == off);
1237
1238         /*
1239          * Kill the leaf entry by marking it stale.
1240          * Log the leaf block changes.
1241          */
1242         leafhdr.stale++;
1243         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1244         xfs_dir3_leaf_log_header(tp, bp);
1245
1246         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1247         xfs_dir3_leaf_log_ents(tp, bp, index, index);
1248
1249         /*
1250          * Make the data entry free.  Keep track of the longest freespace
1251          * in the data block in case it changes.
1252          */
1253         dbp = dblk->bp;
1254         hdr = dbp->b_addr;
1255         dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
1256         bf = xfs_dir3_data_bestfree_p(hdr);
1257         longest = be16_to_cpu(bf[0].length);
1258         needlog = needscan = 0;
1259         xfs_dir2_data_make_free(tp, dbp, off,
1260                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1261         /*
1262          * Rescan the data block freespaces for bestfree.
1263          * Log the data block header if needed.
1264          */
1265         if (needscan)
1266                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1267         if (needlog)
1268                 xfs_dir2_data_log_header(tp, dbp);
1269         xfs_dir3_data_check(dp, dbp);
1270         /*
1271          * If the longest data block freespace changes, need to update
1272          * the corresponding freeblock entry.
1273          */
1274         if (longest < be16_to_cpu(bf[0].length)) {
1275                 int             error;          /* error return value */
1276                 struct xfs_buf  *fbp;           /* freeblock buffer */
1277                 xfs_dir2_db_t   fdb;            /* freeblock block number */
1278                 int             findex;         /* index in freeblock entries */
1279                 xfs_dir2_free_t *free;          /* freeblock structure */
1280
1281                 /*
1282                  * Convert the data block number to a free block,
1283                  * read in the free block.
1284                  */
1285                 fdb = xfs_dir2_db_to_fdb(mp, db);
1286                 error = xfs_dir2_free_read(tp, dp, xfs_dir2_db_to_da(mp, fdb),
1287                                            &fbp);
1288                 if (error)
1289                         return error;
1290                 free = fbp->b_addr;
1291 #ifdef DEBUG
1292         {
1293                 struct xfs_dir3_icfree_hdr freehdr;
1294                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1295                 ASSERT(freehdr.firstdb == xfs_dir3_free_max_bests(mp) *
1296                                           (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
1297         }
1298 #endif
1299                 /*
1300                  * Calculate which entry we need to fix.
1301                  */
1302                 findex = xfs_dir2_db_to_fdindex(mp, db);
1303                 longest = be16_to_cpu(bf[0].length);
1304                 /*
1305                  * If the data block is now empty we can get rid of it
1306                  * (usually).
1307                  */
1308                 if (longest == mp->m_dirblksize -
1309                                xfs_dir3_data_entry_offset(hdr)) {
1310                         /*
1311                          * Try to punch out the data block.
1312                          */
1313                         error = xfs_dir2_shrink_inode(args, db, dbp);
1314                         if (error == 0) {
1315                                 dblk->bp = NULL;
1316                                 hdr = NULL;
1317                         }
1318                         /*
1319                          * We can get ENOSPC if there's no space reservation.
1320                          * In this case just drop the buffer and some one else
1321                          * will eventually get rid of the empty block.
1322                          */
1323                         else if (!(error == ENOSPC && args->total == 0))
1324                                 return error;
1325                 }
1326                 /*
1327                  * If we got rid of the data block, we can eliminate that entry
1328                  * in the free block.
1329                  */
1330                 error = xfs_dir3_data_block_free(args, hdr, free,
1331                                                  fdb, findex, fbp, longest);
1332                 if (error)
1333                         return error;
1334         }
1335
1336         xfs_dir3_leaf_check(mp, bp);
1337         /*
1338          * Return indication of whether this leaf block is empty enough
1339          * to justify trying to join it with a neighbor.
1340          */
1341         *rval = (xfs_dir3_leaf_hdr_size(leaf) +
1342                  (uint)sizeof(ents[0]) * (leafhdr.count - leafhdr.stale)) <
1343                 mp->m_dir_magicpct;
1344         return 0;
1345 }
1346
1347 /*
1348  * Split the leaf entries in the old block into old and new blocks.
1349  */
1350 int                                             /* error */
1351 xfs_dir2_leafn_split(
1352         xfs_da_state_t          *state,         /* btree cursor */
1353         xfs_da_state_blk_t      *oldblk,        /* original block */
1354         xfs_da_state_blk_t      *newblk)        /* newly created block */
1355 {
1356         xfs_da_args_t           *args;          /* operation arguments */
1357         xfs_dablk_t             blkno;          /* new leaf block number */
1358         int                     error;          /* error return value */
1359         xfs_mount_t             *mp;            /* filesystem mount point */
1360
1361         /*
1362          * Allocate space for a new leaf node.
1363          */
1364         args = state->args;
1365         mp = args->dp->i_mount;
1366         ASSERT(args != NULL);
1367         ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1368         error = xfs_da_grow_inode(args, &blkno);
1369         if (error) {
1370                 return error;
1371         }
1372         /*
1373          * Initialize the new leaf block.
1374          */
1375         error = xfs_dir3_leaf_get_buf(args, xfs_dir2_da_to_db(mp, blkno),
1376                                       &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1377         if (error)
1378                 return error;
1379
1380         newblk->blkno = blkno;
1381         newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1382         /*
1383          * Rebalance the entries across the two leaves, link the new
1384          * block into the leaves.
1385          */
1386         xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1387         error = xfs_da3_blk_link(state, oldblk, newblk);
1388         if (error) {
1389                 return error;
1390         }
1391         /*
1392          * Insert the new entry in the correct block.
1393          */
1394         if (state->inleaf)
1395                 error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1396         else
1397                 error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1398         /*
1399          * Update last hashval in each block since we added the name.
1400          */
1401         oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1402         newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1403         xfs_dir3_leaf_check(mp, oldblk->bp);
1404         xfs_dir3_leaf_check(mp, newblk->bp);
1405         return error;
1406 }
1407
1408 /*
1409  * Check a leaf block and its neighbors to see if the block should be
1410  * collapsed into one or the other neighbor.  Always keep the block
1411  * with the smaller block number.
1412  * If the current block is over 50% full, don't try to join it, return 0.
1413  * If the block is empty, fill in the state structure and return 2.
1414  * If it can be collapsed, fill in the state structure and return 1.
1415  * If nothing can be done, return 0.
1416  */
1417 int                                             /* error */
1418 xfs_dir2_leafn_toosmall(
1419         xfs_da_state_t          *state,         /* btree cursor */
1420         int                     *action)        /* resulting action to take */
1421 {
1422         xfs_da_state_blk_t      *blk;           /* leaf block */
1423         xfs_dablk_t             blkno;          /* leaf block number */
1424         struct xfs_buf          *bp;            /* leaf buffer */
1425         int                     bytes;          /* bytes in use */
1426         int                     count;          /* leaf live entry count */
1427         int                     error;          /* error return value */
1428         int                     forward;        /* sibling block direction */
1429         int                     i;              /* sibling counter */
1430         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1431         int                     rval;           /* result from path_shift */
1432         struct xfs_dir3_icleaf_hdr leafhdr;
1433         struct xfs_dir2_leaf_entry *ents;
1434
1435         /*
1436          * Check for the degenerate case of the block being over 50% full.
1437          * If so, it's not worth even looking to see if we might be able
1438          * to coalesce with a sibling.
1439          */
1440         blk = &state->path.blk[state->path.active - 1];
1441         leaf = blk->bp->b_addr;
1442         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1443         ents = xfs_dir3_leaf_ents_p(leaf);
1444         xfs_dir3_leaf_check(state->args->dp->i_mount, blk->bp);
1445
1446         count = leafhdr.count - leafhdr.stale;
1447         bytes = xfs_dir3_leaf_hdr_size(leaf) + count * sizeof(ents[0]);
1448         if (bytes > (state->blocksize >> 1)) {
1449                 /*
1450                  * Blk over 50%, don't try to join.
1451                  */
1452                 *action = 0;
1453                 return 0;
1454         }
1455         /*
1456          * Check for the degenerate case of the block being empty.
1457          * If the block is empty, we'll simply delete it, no need to
1458          * coalesce it with a sibling block.  We choose (arbitrarily)
1459          * to merge with the forward block unless it is NULL.
1460          */
1461         if (count == 0) {
1462                 /*
1463                  * Make altpath point to the block we want to keep and
1464                  * path point to the block we want to drop (this one).
1465                  */
1466                 forward = (leafhdr.forw != 0);
1467                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1468                 error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1469                         &rval);
1470                 if (error)
1471                         return error;
1472                 *action = rval ? 2 : 0;
1473                 return 0;
1474         }
1475         /*
1476          * Examine each sibling block to see if we can coalesce with
1477          * at least 25% free space to spare.  We need to figure out
1478          * whether to merge with the forward or the backward block.
1479          * We prefer coalescing with the lower numbered sibling so as
1480          * to shrink a directory over time.
1481          */
1482         forward = leafhdr.forw < leafhdr.back;
1483         for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1484                 struct xfs_dir3_icleaf_hdr hdr2;
1485
1486                 blkno = forward ? leafhdr.forw : leafhdr.back;
1487                 if (blkno == 0)
1488                         continue;
1489                 /*
1490                  * Read the sibling leaf block.
1491                  */
1492                 error = xfs_dir3_leafn_read(state->args->trans, state->args->dp,
1493                                             blkno, -1, &bp);
1494                 if (error)
1495                         return error;
1496
1497                 /*
1498                  * Count bytes in the two blocks combined.
1499                  */
1500                 count = leafhdr.count - leafhdr.stale;
1501                 bytes = state->blocksize - (state->blocksize >> 2);
1502
1503                 leaf = bp->b_addr;
1504                 xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf);
1505                 ents = xfs_dir3_leaf_ents_p(leaf);
1506                 count += hdr2.count - hdr2.stale;
1507                 bytes -= count * sizeof(ents[0]);
1508
1509                 /*
1510                  * Fits with at least 25% to spare.
1511                  */
1512                 if (bytes >= 0)
1513                         break;
1514                 xfs_trans_brelse(state->args->trans, bp);
1515         }
1516         /*
1517          * Didn't like either block, give up.
1518          */
1519         if (i >= 2) {
1520                 *action = 0;
1521                 return 0;
1522         }
1523
1524         /*
1525          * Make altpath point to the block we want to keep (the lower
1526          * numbered block) and path point to the block we want to drop.
1527          */
1528         memcpy(&state->altpath, &state->path, sizeof(state->path));
1529         if (blkno < blk->blkno)
1530                 error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1531                         &rval);
1532         else
1533                 error = xfs_da3_path_shift(state, &state->path, forward, 0,
1534                         &rval);
1535         if (error) {
1536                 return error;
1537         }
1538         *action = rval ? 0 : 1;
1539         return 0;
1540 }
1541
1542 /*
1543  * Move all the leaf entries from drop_blk to save_blk.
1544  * This is done as part of a join operation.
1545  */
1546 void
1547 xfs_dir2_leafn_unbalance(
1548         xfs_da_state_t          *state,         /* cursor */
1549         xfs_da_state_blk_t      *drop_blk,      /* dead block */
1550         xfs_da_state_blk_t      *save_blk)      /* surviving block */
1551 {
1552         xfs_da_args_t           *args;          /* operation arguments */
1553         xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1554         xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1555         struct xfs_dir3_icleaf_hdr savehdr;
1556         struct xfs_dir3_icleaf_hdr drophdr;
1557         struct xfs_dir2_leaf_entry *sents;
1558         struct xfs_dir2_leaf_entry *dents;
1559
1560         args = state->args;
1561         ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1562         ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1563         drop_leaf = drop_blk->bp->b_addr;
1564         save_leaf = save_blk->bp->b_addr;
1565
1566         xfs_dir3_leaf_hdr_from_disk(&savehdr, save_leaf);
1567         xfs_dir3_leaf_hdr_from_disk(&drophdr, drop_leaf);
1568         sents = xfs_dir3_leaf_ents_p(save_leaf);
1569         dents = xfs_dir3_leaf_ents_p(drop_leaf);
1570
1571         /*
1572          * If there are any stale leaf entries, take this opportunity
1573          * to purge them.
1574          */
1575         if (drophdr.stale)
1576                 xfs_dir3_leaf_compact(args, &drophdr, drop_blk->bp);
1577         if (savehdr.stale)
1578                 xfs_dir3_leaf_compact(args, &savehdr, save_blk->bp);
1579
1580         /*
1581          * Move the entries from drop to the appropriate end of save.
1582          */
1583         drop_blk->hashval = be32_to_cpu(dents[drophdr.count - 1].hashval);
1584         if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1585                 xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1586                                         save_blk->bp, &savehdr, sents, 0,
1587                                         drophdr.count);
1588         else
1589                 xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1590                                         save_blk->bp, &savehdr, sents,
1591                                         savehdr.count, drophdr.count);
1592         save_blk->hashval = be32_to_cpu(sents[savehdr.count - 1].hashval);
1593
1594         /* log the changes made when moving the entries */
1595         xfs_dir3_leaf_hdr_to_disk(save_leaf, &savehdr);
1596         xfs_dir3_leaf_hdr_to_disk(drop_leaf, &drophdr);
1597         xfs_dir3_leaf_log_header(args->trans, save_blk->bp);
1598         xfs_dir3_leaf_log_header(args->trans, drop_blk->bp);
1599
1600         xfs_dir3_leaf_check(args->dp->i_mount, save_blk->bp);
1601         xfs_dir3_leaf_check(args->dp->i_mount, drop_blk->bp);
1602 }
1603
1604 /*
1605  * Top-level node form directory addname routine.
1606  */
1607 int                                             /* error */
1608 xfs_dir2_node_addname(
1609         xfs_da_args_t           *args)          /* operation arguments */
1610 {
1611         xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1612         int                     error;          /* error return value */
1613         int                     rval;           /* sub-return value */
1614         xfs_da_state_t          *state;         /* btree cursor */
1615
1616         trace_xfs_dir2_node_addname(args);
1617
1618         /*
1619          * Allocate and initialize the state (btree cursor).
1620          */
1621         state = xfs_da_state_alloc();
1622         state->args = args;
1623         state->mp = args->dp->i_mount;
1624         state->blocksize = state->mp->m_dirblksize;
1625         state->node_ents = state->mp->m_dir_node_ents;
1626         /*
1627          * Look up the name.  We're not supposed to find it, but
1628          * this gives us the insertion point.
1629          */
1630         error = xfs_da3_node_lookup_int(state, &rval);
1631         if (error)
1632                 rval = error;
1633         if (rval != ENOENT) {
1634                 goto done;
1635         }
1636         /*
1637          * Add the data entry to a data block.
1638          * Extravalid is set to a freeblock found by lookup.
1639          */
1640         rval = xfs_dir2_node_addname_int(args,
1641                 state->extravalid ? &state->extrablk : NULL);
1642         if (rval) {
1643                 goto done;
1644         }
1645         blk = &state->path.blk[state->path.active - 1];
1646         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1647         /*
1648          * Add the new leaf entry.
1649          */
1650         rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1651         if (rval == 0) {
1652                 /*
1653                  * It worked, fix the hash values up the btree.
1654                  */
1655                 if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1656                         xfs_da3_fixhashpath(state, &state->path);
1657         } else {
1658                 /*
1659                  * It didn't work, we need to split the leaf block.
1660                  */
1661                 if (args->total == 0) {
1662                         ASSERT(rval == ENOSPC);
1663                         goto done;
1664                 }
1665                 /*
1666                  * Split the leaf block and insert the new entry.
1667                  */
1668                 rval = xfs_da3_split(state);
1669         }
1670 done:
1671         xfs_da_state_free(state);
1672         return rval;
1673 }
1674
1675 /*
1676  * Add the data entry for a node-format directory name addition.
1677  * The leaf entry is added in xfs_dir2_leafn_add.
1678  * We may enter with a freespace block that the lookup found.
1679  */
1680 static int                                      /* error */
1681 xfs_dir2_node_addname_int(
1682         xfs_da_args_t           *args,          /* operation arguments */
1683         xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1684 {
1685         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1686         xfs_dir2_db_t           dbno;           /* data block number */
1687         struct xfs_buf          *dbp;           /* data block buffer */
1688         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1689         xfs_inode_t             *dp;            /* incore directory inode */
1690         xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1691         int                     error;          /* error return value */
1692         xfs_dir2_db_t           fbno;           /* freespace block number */
1693         struct xfs_buf          *fbp;           /* freespace buffer */
1694         int                     findex;         /* freespace entry index */
1695         xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1696         xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1697         xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1698         int                     length;         /* length of the new entry */
1699         int                     logfree;        /* need to log free entry */
1700         xfs_mount_t             *mp;            /* filesystem mount point */
1701         int                     needlog;        /* need to log data header */
1702         int                     needscan;       /* need to rescan data frees */
1703         __be16                  *tagp;          /* data entry tag pointer */
1704         xfs_trans_t             *tp;            /* transaction pointer */
1705         __be16                  *bests;
1706         struct xfs_dir3_icfree_hdr freehdr;
1707         struct xfs_dir2_data_free *bf;
1708
1709         dp = args->dp;
1710         mp = dp->i_mount;
1711         tp = args->trans;
1712         length = xfs_dir2_data_entsize(args->namelen);
1713         /*
1714          * If we came in with a freespace block that means that lookup
1715          * found an entry with our hash value.  This is the freespace
1716          * block for that data entry.
1717          */
1718         if (fblk) {
1719                 fbp = fblk->bp;
1720                 /*
1721                  * Remember initial freespace block number.
1722                  */
1723                 ifbno = fblk->blkno;
1724                 free = fbp->b_addr;
1725                 findex = fblk->index;
1726                 bests = xfs_dir3_free_bests_p(mp, free);
1727                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1728
1729                 /*
1730                  * This means the free entry showed that the data block had
1731                  * space for our entry, so we remembered it.
1732                  * Use that data block.
1733                  */
1734                 if (findex >= 0) {
1735                         ASSERT(findex < freehdr.nvalid);
1736                         ASSERT(be16_to_cpu(bests[findex]) != NULLDATAOFF);
1737                         ASSERT(be16_to_cpu(bests[findex]) >= length);
1738                         dbno = freehdr.firstdb + findex;
1739                 } else {
1740                         /*
1741                          * The data block looked at didn't have enough room.
1742                          * We'll start at the beginning of the freespace entries.
1743                          */
1744                         dbno = -1;
1745                         findex = 0;
1746                 }
1747         } else {
1748                 /*
1749                  * Didn't come in with a freespace block, so no data block.
1750                  */
1751                 ifbno = dbno = -1;
1752                 fbp = NULL;
1753                 findex = 0;
1754         }
1755
1756         /*
1757          * If we don't have a data block yet, we're going to scan the
1758          * freespace blocks looking for one.  Figure out what the
1759          * highest freespace block number is.
1760          */
1761         if (dbno == -1) {
1762                 xfs_fileoff_t   fo;             /* freespace block number */
1763
1764                 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1765                         return error;
1766                 lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1767                 fbno = ifbno;
1768         }
1769         /*
1770          * While we haven't identified a data block, search the freeblock
1771          * data for a good data block.  If we find a null freeblock entry,
1772          * indicating a hole in the data blocks, remember that.
1773          */
1774         while (dbno == -1) {
1775                 /*
1776                  * If we don't have a freeblock in hand, get the next one.
1777                  */
1778                 if (fbp == NULL) {
1779                         /*
1780                          * Happens the first time through unless lookup gave
1781                          * us a freespace block to start with.
1782                          */
1783                         if (++fbno == 0)
1784                                 fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1785                         /*
1786                          * If it's ifbno we already looked at it.
1787                          */
1788                         if (fbno == ifbno)
1789                                 fbno++;
1790                         /*
1791                          * If it's off the end we're done.
1792                          */
1793                         if (fbno >= lastfbno)
1794                                 break;
1795                         /*
1796                          * Read the block.  There can be holes in the
1797                          * freespace blocks, so this might not succeed.
1798                          * This should be really rare, so there's no reason
1799                          * to avoid it.
1800                          */
1801                         error = xfs_dir2_free_try_read(tp, dp,
1802                                                 xfs_dir2_db_to_da(mp, fbno),
1803                                                 &fbp);
1804                         if (error)
1805                                 return error;
1806                         if (!fbp)
1807                                 continue;
1808                         free = fbp->b_addr;
1809                         findex = 0;
1810                 }
1811                 /*
1812                  * Look at the current free entry.  Is it good enough?
1813                  *
1814                  * The bests initialisation should be where the bufer is read in
1815                  * the above branch. But gcc is too stupid to realise that bests
1816                  * and the freehdr are actually initialised if they are placed
1817                  * there, so we have to do it here to avoid warnings. Blech.
1818                  */
1819                 bests = xfs_dir3_free_bests_p(mp, free);
1820                 xfs_dir3_free_hdr_from_disk(&freehdr, free);
1821                 if (be16_to_cpu(bests[findex]) != NULLDATAOFF &&
1822                     be16_to_cpu(bests[findex]) >= length)
1823                         dbno = freehdr.firstdb + findex;
1824                 else {
1825                         /*
1826                          * Are we done with the freeblock?
1827                          */
1828                         if (++findex == freehdr.nvalid) {
1829                                 /*
1830                                  * Drop the block.
1831                                  */
1832                                 xfs_trans_brelse(tp, fbp);
1833                                 fbp = NULL;
1834                                 if (fblk && fblk->bp)
1835                                         fblk->bp = NULL;
1836                         }
1837                 }
1838         }
1839         /*
1840          * If we don't have a data block, we need to allocate one and make
1841          * the freespace entries refer to it.
1842          */
1843         if (unlikely(dbno == -1)) {
1844                 /*
1845                  * Not allowed to allocate, return failure.
1846                  */
1847                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
1848                         return XFS_ERROR(ENOSPC);
1849
1850                 /*
1851                  * Allocate and initialize the new data block.
1852                  */
1853                 if (unlikely((error = xfs_dir2_grow_inode(args,
1854                                                          XFS_DIR2_DATA_SPACE,
1855                                                          &dbno)) ||
1856                     (error = xfs_dir3_data_init(args, dbno, &dbp))))
1857                         return error;
1858
1859                 /*
1860                  * If (somehow) we have a freespace block, get rid of it.
1861                  */
1862                 if (fbp)
1863                         xfs_trans_brelse(tp, fbp);
1864                 if (fblk && fblk->bp)
1865                         fblk->bp = NULL;
1866
1867                 /*
1868                  * Get the freespace block corresponding to the data block
1869                  * that was just allocated.
1870                  */
1871                 fbno = xfs_dir2_db_to_fdb(mp, dbno);
1872                 error = xfs_dir2_free_try_read(tp, dp,
1873                                                xfs_dir2_db_to_da(mp, fbno),
1874                                                &fbp);
1875                 if (error)
1876                         return error;
1877
1878                 /*
1879                  * If there wasn't a freespace block, the read will
1880                  * return a NULL fbp.  Allocate and initialize a new one.
1881                  */
1882                 if (!fbp) {
1883                         error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1884                                                     &fbno);
1885                         if (error)
1886                                 return error;
1887
1888                         if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1889                                 xfs_alert(mp,
1890                         "%s: dir ino %llu needed freesp block %lld for\n"
1891                         "  data block %lld, got %lld ifbno %llu lastfbno %d",
1892                                         __func__, (unsigned long long)dp->i_ino,
1893                                         (long long)xfs_dir2_db_to_fdb(mp, dbno),
1894                                         (long long)dbno, (long long)fbno,
1895                                         (unsigned long long)ifbno, lastfbno);
1896                                 if (fblk) {
1897                                         xfs_alert(mp,
1898                                 " fblk 0x%p blkno %llu index %d magic 0x%x",
1899                                                 fblk,
1900                                                 (unsigned long long)fblk->blkno,
1901                                                 fblk->index,
1902                                                 fblk->magic);
1903                                 } else {
1904                                         xfs_alert(mp, " ... fblk is NULL");
1905                                 }
1906                                 XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1907                                                  XFS_ERRLEVEL_LOW, mp);
1908                                 return XFS_ERROR(EFSCORRUPTED);
1909                         }
1910
1911                         /*
1912                          * Get a buffer for the new block.
1913                          */
1914                         error = xfs_dir3_free_get_buf(tp, dp, fbno, &fbp);
1915                         if (error)
1916                                 return error;
1917                         free = fbp->b_addr;
1918                         bests = xfs_dir3_free_bests_p(mp, free);
1919                         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1920
1921                         /*
1922                          * Remember the first slot as our empty slot.
1923                          */
1924                         freehdr.firstdb = (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1925                                         xfs_dir3_free_max_bests(mp);
1926                 } else {
1927                         free = fbp->b_addr;
1928                         bests = xfs_dir3_free_bests_p(mp, free);
1929                         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1930                 }
1931
1932                 /*
1933                  * Set the freespace block index from the data block number.
1934                  */
1935                 findex = xfs_dir2_db_to_fdindex(mp, dbno);
1936                 /*
1937                  * If it's after the end of the current entries in the
1938                  * freespace block, extend that table.
1939                  */
1940                 if (findex >= freehdr.nvalid) {
1941                         ASSERT(findex < xfs_dir3_free_max_bests(mp));
1942                         freehdr.nvalid = findex + 1;
1943                         /*
1944                          * Tag new entry so nused will go up.
1945                          */
1946                         bests[findex] = cpu_to_be16(NULLDATAOFF);
1947                 }
1948                 /*
1949                  * If this entry was for an empty data block
1950                  * (this should always be true) then update the header.
1951                  */
1952                 if (bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1953                         freehdr.nused++;
1954                         xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
1955                         xfs_dir2_free_log_header(tp, fbp);
1956                 }
1957                 /*
1958                  * Update the real value in the table.
1959                  * We haven't allocated the data entry yet so this will
1960                  * change again.
1961                  */
1962                 hdr = dbp->b_addr;
1963                 bf = xfs_dir3_data_bestfree_p(hdr);
1964                 bests[findex] = bf[0].length;
1965                 logfree = 1;
1966         }
1967         /*
1968          * We had a data block so we don't have to make a new one.
1969          */
1970         else {
1971                 /*
1972                  * If just checking, we succeeded.
1973                  */
1974                 if (args->op_flags & XFS_DA_OP_JUSTCHECK)
1975                         return 0;
1976
1977                 /*
1978                  * Read the data block in.
1979                  */
1980                 error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1981                                            -1, &dbp);
1982                 if (error)
1983                         return error;
1984                 hdr = dbp->b_addr;
1985                 bf = xfs_dir3_data_bestfree_p(hdr);
1986                 logfree = 0;
1987         }
1988         ASSERT(be16_to_cpu(bf[0].length) >= length);
1989         /*
1990          * Point to the existing unused space.
1991          */
1992         dup = (xfs_dir2_data_unused_t *)
1993               ((char *)hdr + be16_to_cpu(bf[0].offset));
1994         needscan = needlog = 0;
1995         /*
1996          * Mark the first part of the unused space, inuse for us.
1997          */
1998         xfs_dir2_data_use_free(tp, dbp, dup,
1999                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
2000                 &needlog, &needscan);
2001         /*
2002          * Fill in the new entry and log it.
2003          */
2004         dep = (xfs_dir2_data_entry_t *)dup;
2005         dep->inumber = cpu_to_be64(args->inumber);
2006         dep->namelen = args->namelen;
2007         memcpy(dep->name, args->name, dep->namelen);
2008         tagp = xfs_dir2_data_entry_tag_p(dep);
2009         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
2010         xfs_dir2_data_log_entry(tp, dbp, dep);
2011         /*
2012          * Rescan the block for bestfree if needed.
2013          */
2014         if (needscan)
2015                 xfs_dir2_data_freescan(mp, hdr, &needlog);
2016         /*
2017          * Log the data block header if needed.
2018          */
2019         if (needlog)
2020                 xfs_dir2_data_log_header(tp, dbp);
2021         /*
2022          * If the freespace entry is now wrong, update it.
2023          */
2024         bests = xfs_dir3_free_bests_p(mp, free); /* gcc is so stupid */
2025         if (be16_to_cpu(bests[findex]) != be16_to_cpu(bf[0].length)) {
2026                 bests[findex] = bf[0].length;
2027                 logfree = 1;
2028         }
2029         /*
2030          * Log the freespace entry if needed.
2031          */
2032         if (logfree)
2033                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
2034         /*
2035          * Return the data block and offset in args, then drop the data block.
2036          */
2037         args->blkno = (xfs_dablk_t)dbno;
2038         args->index = be16_to_cpu(*tagp);
2039         return 0;
2040 }
2041
2042 /*
2043  * Lookup an entry in a node-format directory.
2044  * All the real work happens in xfs_da3_node_lookup_int.
2045  * The only real output is the inode number of the entry.
2046  */
2047 int                                             /* error */
2048 xfs_dir2_node_lookup(
2049         xfs_da_args_t   *args)                  /* operation arguments */
2050 {
2051         int             error;                  /* error return value */
2052         int             i;                      /* btree level */
2053         int             rval;                   /* operation return value */
2054         xfs_da_state_t  *state;                 /* btree cursor */
2055
2056         trace_xfs_dir2_node_lookup(args);
2057
2058         /*
2059          * Allocate and initialize the btree cursor.
2060          */
2061         state = xfs_da_state_alloc();
2062         state->args = args;
2063         state->mp = args->dp->i_mount;
2064         state->blocksize = state->mp->m_dirblksize;
2065         state->node_ents = state->mp->m_dir_node_ents;
2066         /*
2067          * Fill in the path to the entry in the cursor.
2068          */
2069         error = xfs_da3_node_lookup_int(state, &rval);
2070         if (error)
2071                 rval = error;
2072         else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
2073                 /* If a CI match, dup the actual name and return EEXIST */
2074                 xfs_dir2_data_entry_t   *dep;
2075
2076                 dep = (xfs_dir2_data_entry_t *)
2077                         ((char *)state->extrablk.bp->b_addr +
2078                                                  state->extrablk.index);
2079                 rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
2080         }
2081         /*
2082          * Release the btree blocks and leaf block.
2083          */
2084         for (i = 0; i < state->path.active; i++) {
2085                 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2086                 state->path.blk[i].bp = NULL;
2087         }
2088         /*
2089          * Release the data block if we have it.
2090          */
2091         if (state->extravalid && state->extrablk.bp) {
2092                 xfs_trans_brelse(args->trans, state->extrablk.bp);
2093                 state->extrablk.bp = NULL;
2094         }
2095         xfs_da_state_free(state);
2096         return rval;
2097 }
2098
2099 /*
2100  * Remove an entry from a node-format directory.
2101  */
2102 int                                             /* error */
2103 xfs_dir2_node_removename(
2104         xfs_da_args_t           *args)          /* operation arguments */
2105 {
2106         xfs_da_state_blk_t      *blk;           /* leaf block */
2107         int                     error;          /* error return value */
2108         int                     rval;           /* operation return value */
2109         xfs_da_state_t          *state;         /* btree cursor */
2110
2111         trace_xfs_dir2_node_removename(args);
2112
2113         /*
2114          * Allocate and initialize the btree cursor.
2115          */
2116         state = xfs_da_state_alloc();
2117         state->args = args;
2118         state->mp = args->dp->i_mount;
2119         state->blocksize = state->mp->m_dirblksize;
2120         state->node_ents = state->mp->m_dir_node_ents;
2121         /*
2122          * Look up the entry we're deleting, set up the cursor.
2123          */
2124         error = xfs_da3_node_lookup_int(state, &rval);
2125         if (error)
2126                 rval = error;
2127         /*
2128          * Didn't find it, upper layer screwed up.
2129          */
2130         if (rval != EEXIST) {
2131                 xfs_da_state_free(state);
2132                 return rval;
2133         }
2134         blk = &state->path.blk[state->path.active - 1];
2135         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2136         ASSERT(state->extravalid);
2137         /*
2138          * Remove the leaf and data entries.
2139          * Extrablk refers to the data block.
2140          */
2141         error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
2142                 &state->extrablk, &rval);
2143         if (error)
2144                 return error;
2145         /*
2146          * Fix the hash values up the btree.
2147          */
2148         xfs_da3_fixhashpath(state, &state->path);
2149         /*
2150          * If we need to join leaf blocks, do it.
2151          */
2152         if (rval && state->path.active > 1)
2153                 error = xfs_da3_join(state);
2154         /*
2155          * If no errors so far, try conversion to leaf format.
2156          */
2157         if (!error)
2158                 error = xfs_dir2_node_to_leaf(state);
2159         xfs_da_state_free(state);
2160         return error;
2161 }
2162
2163 /*
2164  * Replace an entry's inode number in a node-format directory.
2165  */
2166 int                                             /* error */
2167 xfs_dir2_node_replace(
2168         xfs_da_args_t           *args)          /* operation arguments */
2169 {
2170         xfs_da_state_blk_t      *blk;           /* leaf block */
2171         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
2172         xfs_dir2_data_entry_t   *dep;           /* data entry changed */
2173         int                     error;          /* error return value */
2174         int                     i;              /* btree level */
2175         xfs_ino_t               inum;           /* new inode number */
2176         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2177         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
2178         int                     rval;           /* internal return value */
2179         xfs_da_state_t          *state;         /* btree cursor */
2180
2181         trace_xfs_dir2_node_replace(args);
2182
2183         /*
2184          * Allocate and initialize the btree cursor.
2185          */
2186         state = xfs_da_state_alloc();
2187         state->args = args;
2188         state->mp = args->dp->i_mount;
2189         state->blocksize = state->mp->m_dirblksize;
2190         state->node_ents = state->mp->m_dir_node_ents;
2191         inum = args->inumber;
2192         /*
2193          * Lookup the entry to change in the btree.
2194          */
2195         error = xfs_da3_node_lookup_int(state, &rval);
2196         if (error) {
2197                 rval = error;
2198         }
2199         /*
2200          * It should be found, since the vnodeops layer has looked it up
2201          * and locked it.  But paranoia is good.
2202          */
2203         if (rval == EEXIST) {
2204                 struct xfs_dir2_leaf_entry *ents;
2205                 /*
2206                  * Find the leaf entry.
2207                  */
2208                 blk = &state->path.blk[state->path.active - 1];
2209                 ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2210                 leaf = blk->bp->b_addr;
2211                 ents = xfs_dir3_leaf_ents_p(leaf);
2212                 lep = &ents[blk->index];
2213                 ASSERT(state->extravalid);
2214                 /*
2215                  * Point to the data entry.
2216                  */
2217                 hdr = state->extrablk.bp->b_addr;
2218                 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
2219                        hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
2220                 dep = (xfs_dir2_data_entry_t *)
2221                       ((char *)hdr +
2222                        xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
2223                 ASSERT(inum != be64_to_cpu(dep->inumber));
2224                 /*
2225                  * Fill in the new inode number and log the entry.
2226                  */
2227                 dep->inumber = cpu_to_be64(inum);
2228                 xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
2229                 rval = 0;
2230         }
2231         /*
2232          * Didn't find it, and we're holding a data block.  Drop it.
2233          */
2234         else if (state->extravalid) {
2235                 xfs_trans_brelse(args->trans, state->extrablk.bp);
2236                 state->extrablk.bp = NULL;
2237         }
2238         /*
2239          * Release all the buffers in the cursor.
2240          */
2241         for (i = 0; i < state->path.active; i++) {
2242                 xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2243                 state->path.blk[i].bp = NULL;
2244         }
2245         xfs_da_state_free(state);
2246         return rval;
2247 }
2248
2249 /*
2250  * Trim off a trailing empty freespace block.
2251  * Return (in rvalp) 1 if we did it, 0 if not.
2252  */
2253 int                                             /* error */
2254 xfs_dir2_node_trim_free(
2255         xfs_da_args_t           *args,          /* operation arguments */
2256         xfs_fileoff_t           fo,             /* free block number */
2257         int                     *rvalp)         /* out: did something */
2258 {
2259         struct xfs_buf          *bp;            /* freespace buffer */
2260         xfs_inode_t             *dp;            /* incore directory inode */
2261         int                     error;          /* error return code */
2262         xfs_dir2_free_t         *free;          /* freespace structure */
2263         xfs_mount_t             *mp;            /* filesystem mount point */
2264         xfs_trans_t             *tp;            /* transaction pointer */
2265         struct xfs_dir3_icfree_hdr freehdr;
2266
2267         dp = args->dp;
2268         mp = dp->i_mount;
2269         tp = args->trans;
2270         /*
2271          * Read the freespace block.
2272          */
2273         error = xfs_dir2_free_try_read(tp, dp, fo, &bp);
2274         if (error)
2275                 return error;
2276         /*
2277          * There can be holes in freespace.  If fo is a hole, there's
2278          * nothing to do.
2279          */
2280         if (!bp)
2281                 return 0;
2282         free = bp->b_addr;
2283         xfs_dir3_free_hdr_from_disk(&freehdr, free);
2284
2285         /*
2286          * If there are used entries, there's nothing to do.
2287          */
2288         if (freehdr.nused > 0) {
2289                 xfs_trans_brelse(tp, bp);
2290                 *rvalp = 0;
2291                 return 0;
2292         }
2293         /*
2294          * Blow the block away.
2295          */
2296         if ((error =
2297             xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
2298                     bp))) {
2299                 /*
2300                  * Can't fail with ENOSPC since that only happens with no
2301                  * space reservation, when breaking up an extent into two
2302                  * pieces.  This is the last block of an extent.
2303                  */
2304                 ASSERT(error != ENOSPC);
2305                 xfs_trans_brelse(tp, bp);
2306                 return error;
2307         }
2308         /*
2309          * Return that we succeeded.
2310          */
2311         *rvalp = 1;
2312         return 0;
2313 }