linux/fs/xfs/xfs_dir2_node.c
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   1/*
   2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_types.h"
  21#include "xfs_log.h"
  22#include "xfs_trans.h"
  23#include "xfs_sb.h"
  24#include "xfs_ag.h"
  25#include "xfs_mount.h"
  26#include "xfs_da_btree.h"
  27#include "xfs_bmap_btree.h"
  28#include "xfs_dinode.h"
  29#include "xfs_inode.h"
  30#include "xfs_bmap.h"
  31#include "xfs_dir2_format.h"
  32#include "xfs_dir2_priv.h"
  33#include "xfs_error.h"
  34#include "xfs_trace.h"
  35
  36/*
  37 * Function declarations.
  38 */
  39static int xfs_dir2_leafn_add(struct xfs_buf *bp, xfs_da_args_t *args,
  40                              int index);
  41#ifdef DEBUG
  42static void xfs_dir2_leafn_check(struct xfs_inode *dp, struct xfs_buf *bp);
  43#else
  44#define xfs_dir2_leafn_check(dp, bp)
  45#endif
  46static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, struct xfs_buf *bp_s,
  47                                    int start_s, struct xfs_buf *bp_d,
  48                                    int start_d, int count);
  49static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  50                                     xfs_da_state_blk_t *blk1,
  51                                     xfs_da_state_blk_t *blk2);
  52static int xfs_dir2_leafn_remove(xfs_da_args_t *args, struct xfs_buf *bp,
  53                                 int index, xfs_da_state_blk_t *dblk,
  54                                 int *rval);
  55static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  56                                     xfs_da_state_blk_t *fblk);
  57
  58/*
  59 * Log entries from a freespace block.
  60 */
  61STATIC void
  62xfs_dir2_free_log_bests(
  63        struct xfs_trans        *tp,
  64        struct xfs_buf          *bp,
  65        int                     first,          /* first entry to log */
  66        int                     last)           /* last entry to log */
  67{
  68        xfs_dir2_free_t         *free;          /* freespace structure */
  69
  70        free = bp->b_addr;
  71        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
  72        xfs_trans_log_buf(tp, bp,
  73                (uint)((char *)&free->bests[first] - (char *)free),
  74                (uint)((char *)&free->bests[last] - (char *)free +
  75                       sizeof(free->bests[0]) - 1));
  76}
  77
  78/*
  79 * Log header from a freespace block.
  80 */
  81static void
  82xfs_dir2_free_log_header(
  83        struct xfs_trans        *tp,
  84        struct xfs_buf          *bp)
  85{
  86        xfs_dir2_free_t         *free;          /* freespace structure */
  87
  88        free = bp->b_addr;
  89        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
  90        xfs_trans_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
  91                (uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
  92}
  93
  94/*
  95 * Convert a leaf-format directory to a node-format directory.
  96 * We need to change the magic number of the leaf block, and copy
  97 * the freespace table out of the leaf block into its own block.
  98 */
  99int                                             /* error */
 100xfs_dir2_leaf_to_node(
 101        xfs_da_args_t           *args,          /* operation arguments */
 102        struct xfs_buf          *lbp)           /* leaf buffer */
 103{
 104        xfs_inode_t             *dp;            /* incore directory inode */
 105        int                     error;          /* error return value */
 106        struct xfs_buf          *fbp;           /* freespace buffer */
 107        xfs_dir2_db_t           fdb;            /* freespace block number */
 108        xfs_dir2_free_t         *free;          /* freespace structure */
 109        __be16                  *from;          /* pointer to freespace entry */
 110        int                     i;              /* leaf freespace index */
 111        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 112        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 113        xfs_mount_t             *mp;            /* filesystem mount point */
 114        int                     n;              /* count of live freespc ents */
 115        xfs_dir2_data_off_t     off;            /* freespace entry value */
 116        __be16                  *to;            /* pointer to freespace entry */
 117        xfs_trans_t             *tp;            /* transaction pointer */
 118
 119        trace_xfs_dir2_leaf_to_node(args);
 120
 121        dp = args->dp;
 122        mp = dp->i_mount;
 123        tp = args->trans;
 124        /*
 125         * Add a freespace block to the directory.
 126         */
 127        if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 128                return error;
 129        }
 130        ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 131        /*
 132         * Get the buffer for the new freespace block.
 133         */
 134        if ((error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb), -1, &fbp,
 135                        XFS_DATA_FORK))) {
 136                return error;
 137        }
 138        ASSERT(fbp != NULL);
 139        free = fbp->b_addr;
 140        leaf = lbp->b_addr;
 141        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 142        /*
 143         * Initialize the freespace block header.
 144         */
 145        free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
 146        free->hdr.firstdb = 0;
 147        ASSERT(be32_to_cpu(ltp->bestcount) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
 148        free->hdr.nvalid = ltp->bestcount;
 149        /*
 150         * Copy freespace entries from the leaf block to the new block.
 151         * Count active entries.
 152         */
 153        for (i = n = 0, from = xfs_dir2_leaf_bests_p(ltp), to = free->bests;
 154             i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 155                if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 156                        n++;
 157                *to = cpu_to_be16(off);
 158        }
 159        free->hdr.nused = cpu_to_be32(n);
 160        leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 161        /*
 162         * Log everything.
 163         */
 164        xfs_dir2_leaf_log_header(tp, lbp);
 165        xfs_dir2_free_log_header(tp, fbp);
 166        xfs_dir2_free_log_bests(tp, fbp, 0, be32_to_cpu(free->hdr.nvalid) - 1);
 167        xfs_dir2_leafn_check(dp, lbp);
 168        return 0;
 169}
 170
 171/*
 172 * Add a leaf entry to a leaf block in a node-form directory.
 173 * The other work necessary is done from the caller.
 174 */
 175static int                                      /* error */
 176xfs_dir2_leafn_add(
 177        struct xfs_buf          *bp,            /* leaf buffer */
 178        xfs_da_args_t           *args,          /* operation arguments */
 179        int                     index)          /* insertion pt for new entry */
 180{
 181        int                     compact;        /* compacting stale leaves */
 182        xfs_inode_t             *dp;            /* incore directory inode */
 183        int                     highstale;      /* next stale entry */
 184        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 185        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 186        int                     lfloghigh;      /* high leaf entry logging */
 187        int                     lfloglow;       /* low leaf entry logging */
 188        int                     lowstale;       /* previous stale entry */
 189        xfs_mount_t             *mp;            /* filesystem mount point */
 190        xfs_trans_t             *tp;            /* transaction pointer */
 191
 192        trace_xfs_dir2_leafn_add(args, index);
 193
 194        dp = args->dp;
 195        mp = dp->i_mount;
 196        tp = args->trans;
 197        leaf = bp->b_addr;
 198
 199        /*
 200         * Quick check just to make sure we are not going to index
 201         * into other peoples memory
 202         */
 203        if (index < 0)
 204                return XFS_ERROR(EFSCORRUPTED);
 205
 206        /*
 207         * If there are already the maximum number of leaf entries in
 208         * the block, if there are no stale entries it won't fit.
 209         * Caller will do a split.  If there are stale entries we'll do
 210         * a compact.
 211         */
 212
 213        if (be16_to_cpu(leaf->hdr.count) == xfs_dir2_max_leaf_ents(mp)) {
 214                if (!leaf->hdr.stale)
 215                        return XFS_ERROR(ENOSPC);
 216                compact = be16_to_cpu(leaf->hdr.stale) > 1;
 217        } else
 218                compact = 0;
 219        ASSERT(index == 0 || be32_to_cpu(leaf->ents[index - 1].hashval) <= args->hashval);
 220        ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
 221               be32_to_cpu(leaf->ents[index].hashval) >= args->hashval);
 222
 223        if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 224                return 0;
 225
 226        /*
 227         * Compact out all but one stale leaf entry.  Leaves behind
 228         * the entry closest to index.
 229         */
 230        if (compact) {
 231                xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
 232                        &lfloglow, &lfloghigh);
 233        }
 234        /*
 235         * Set impossible logging indices for this case.
 236         */
 237        else if (leaf->hdr.stale) {
 238                lfloglow = be16_to_cpu(leaf->hdr.count);
 239                lfloghigh = -1;
 240        }
 241
 242        /*
 243         * Insert the new entry, log everything.
 244         */
 245        lep = xfs_dir2_leaf_find_entry(leaf, index, compact, lowstale,
 246                                       highstale, &lfloglow, &lfloghigh);
 247
 248        lep->hashval = cpu_to_be32(args->hashval);
 249        lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
 250                                args->blkno, args->index));
 251        xfs_dir2_leaf_log_header(tp, bp);
 252        xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 253        xfs_dir2_leafn_check(dp, bp);
 254        return 0;
 255}
 256
 257#ifdef DEBUG
 258/*
 259 * Check internal consistency of a leafn block.
 260 */
 261void
 262xfs_dir2_leafn_check(
 263        struct xfs_inode *dp,
 264        struct xfs_buf  *bp)
 265{
 266        int             i;                      /* leaf index */
 267        xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 268        xfs_mount_t     *mp;                    /* filesystem mount point */
 269        int             stale;                  /* count of stale leaves */
 270
 271        leaf = bp->b_addr;
 272        mp = dp->i_mount;
 273        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 274        ASSERT(be16_to_cpu(leaf->hdr.count) <= xfs_dir2_max_leaf_ents(mp));
 275        for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
 276                if (i + 1 < be16_to_cpu(leaf->hdr.count)) {
 277                        ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
 278                               be32_to_cpu(leaf->ents[i + 1].hashval));
 279                }
 280                if (leaf->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 281                        stale++;
 282        }
 283        ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
 284}
 285#endif  /* DEBUG */
 286
 287/*
 288 * Return the last hash value in the leaf.
 289 * Stale entries are ok.
 290 */
 291xfs_dahash_t                                    /* hash value */
 292xfs_dir2_leafn_lasthash(
 293        struct xfs_buf  *bp,                    /* leaf buffer */
 294        int             *count)                 /* count of entries in leaf */
 295{
 296        xfs_dir2_leaf_t *leaf;                  /* leaf structure */
 297
 298        leaf = bp->b_addr;
 299        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 300        if (count)
 301                *count = be16_to_cpu(leaf->hdr.count);
 302        if (!leaf->hdr.count)
 303                return 0;
 304        return be32_to_cpu(leaf->ents[be16_to_cpu(leaf->hdr.count) - 1].hashval);
 305}
 306
 307/*
 308 * Look up a leaf entry for space to add a name in a node-format leaf block.
 309 * The extrablk in state is a freespace block.
 310 */
 311STATIC int
 312xfs_dir2_leafn_lookup_for_addname(
 313        struct xfs_buf          *bp,            /* leaf buffer */
 314        xfs_da_args_t           *args,          /* operation arguments */
 315        int                     *indexp,        /* out: leaf entry index */
 316        xfs_da_state_t          *state)         /* state to fill in */
 317{
 318        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 319        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 320        xfs_dir2_db_t           curfdb = -1;    /* current free block number */
 321        xfs_inode_t             *dp;            /* incore directory inode */
 322        int                     error;          /* error return value */
 323        int                     fi;             /* free entry index */
 324        xfs_dir2_free_t         *free = NULL;   /* free block structure */
 325        int                     index;          /* leaf entry index */
 326        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 327        int                     length;         /* length of new data entry */
 328        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 329        xfs_mount_t             *mp;            /* filesystem mount point */
 330        xfs_dir2_db_t           newdb;          /* new data block number */
 331        xfs_dir2_db_t           newfdb;         /* new free block number */
 332        xfs_trans_t             *tp;            /* transaction pointer */
 333
 334        dp = args->dp;
 335        tp = args->trans;
 336        mp = dp->i_mount;
 337        leaf = bp->b_addr;
 338        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 339#ifdef __KERNEL__
 340        ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
 341#endif
 342        xfs_dir2_leafn_check(dp, bp);
 343        /*
 344         * Look up the hash value in the leaf entries.
 345         */
 346        index = xfs_dir2_leaf_search_hash(args, bp);
 347        /*
 348         * Do we have a buffer coming in?
 349         */
 350        if (state->extravalid) {
 351                /* If so, it's a free block buffer, get the block number. */
 352                curbp = state->extrablk.bp;
 353                curfdb = state->extrablk.blkno;
 354                free = curbp->b_addr;
 355                ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
 356        }
 357        length = xfs_dir2_data_entsize(args->namelen);
 358        /*
 359         * Loop over leaf entries with the right hash value.
 360         */
 361        for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
 362                                be32_to_cpu(lep->hashval) == args->hashval;
 363                                lep++, index++) {
 364                /*
 365                 * Skip stale leaf entries.
 366                 */
 367                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 368                        continue;
 369                /*
 370                 * Pull the data block number from the entry.
 371                 */
 372                newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 373                /*
 374                 * For addname, we're looking for a place to put the new entry.
 375                 * We want to use a data block with an entry of equal
 376                 * hash value to ours if there is one with room.
 377                 *
 378                 * If this block isn't the data block we already have
 379                 * in hand, take a look at it.
 380                 */
 381                if (newdb != curdb) {
 382                        curdb = newdb;
 383                        /*
 384                         * Convert the data block to the free block
 385                         * holding its freespace information.
 386                         */
 387                        newfdb = xfs_dir2_db_to_fdb(mp, newdb);
 388                        /*
 389                         * If it's not the one we have in hand, read it in.
 390                         */
 391                        if (newfdb != curfdb) {
 392                                /*
 393                                 * If we had one before, drop it.
 394                                 */
 395                                if (curbp)
 396                                        xfs_trans_brelse(tp, curbp);
 397                                /*
 398                                 * Read the free block.
 399                                 */
 400                                error = xfs_da_read_buf(tp, dp,
 401                                                xfs_dir2_db_to_da(mp, newfdb),
 402                                                -1, &curbp, XFS_DATA_FORK);
 403                                if (error)
 404                                        return error;
 405                                free = curbp->b_addr;
 406                                ASSERT(be32_to_cpu(free->hdr.magic) ==
 407                                        XFS_DIR2_FREE_MAGIC);
 408                                ASSERT((be32_to_cpu(free->hdr.firstdb) %
 409                                        xfs_dir2_free_max_bests(mp)) == 0);
 410                                ASSERT(be32_to_cpu(free->hdr.firstdb) <= curdb);
 411                                ASSERT(curdb < be32_to_cpu(free->hdr.firstdb) +
 412                                        be32_to_cpu(free->hdr.nvalid));
 413                        }
 414                        /*
 415                         * Get the index for our entry.
 416                         */
 417                        fi = xfs_dir2_db_to_fdindex(mp, curdb);
 418                        /*
 419                         * If it has room, return it.
 420                         */
 421                        if (unlikely(free->bests[fi] ==
 422                            cpu_to_be16(NULLDATAOFF))) {
 423                                XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 424                                                        XFS_ERRLEVEL_LOW, mp);
 425                                if (curfdb != newfdb)
 426                                        xfs_trans_brelse(tp, curbp);
 427                                return XFS_ERROR(EFSCORRUPTED);
 428                        }
 429                        curfdb = newfdb;
 430                        if (be16_to_cpu(free->bests[fi]) >= length)
 431                                goto out;
 432                }
 433        }
 434        /* Didn't find any space */
 435        fi = -1;
 436out:
 437        ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 438        if (curbp) {
 439                /* Giving back a free block. */
 440                state->extravalid = 1;
 441                state->extrablk.bp = curbp;
 442                state->extrablk.index = fi;
 443                state->extrablk.blkno = curfdb;
 444                state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 445        } else {
 446                state->extravalid = 0;
 447        }
 448        /*
 449         * Return the index, that will be the insertion point.
 450         */
 451        *indexp = index;
 452        return XFS_ERROR(ENOENT);
 453}
 454
 455/*
 456 * Look up a leaf entry in a node-format leaf block.
 457 * The extrablk in state a data block.
 458 */
 459STATIC int
 460xfs_dir2_leafn_lookup_for_entry(
 461        struct xfs_buf          *bp,            /* leaf buffer */
 462        xfs_da_args_t           *args,          /* operation arguments */
 463        int                     *indexp,        /* out: leaf entry index */
 464        xfs_da_state_t          *state)         /* state to fill in */
 465{
 466        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 467        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 468        xfs_dir2_data_entry_t   *dep;           /* data block entry */
 469        xfs_inode_t             *dp;            /* incore directory inode */
 470        int                     error;          /* error return value */
 471        int                     index;          /* leaf entry index */
 472        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 473        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 474        xfs_mount_t             *mp;            /* filesystem mount point */
 475        xfs_dir2_db_t           newdb;          /* new data block number */
 476        xfs_trans_t             *tp;            /* transaction pointer */
 477        enum xfs_dacmp          cmp;            /* comparison result */
 478
 479        dp = args->dp;
 480        tp = args->trans;
 481        mp = dp->i_mount;
 482        leaf = bp->b_addr;
 483        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 484#ifdef __KERNEL__
 485        ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
 486#endif
 487        xfs_dir2_leafn_check(dp, bp);
 488        /*
 489         * Look up the hash value in the leaf entries.
 490         */
 491        index = xfs_dir2_leaf_search_hash(args, bp);
 492        /*
 493         * Do we have a buffer coming in?
 494         */
 495        if (state->extravalid) {
 496                curbp = state->extrablk.bp;
 497                curdb = state->extrablk.blkno;
 498        }
 499        /*
 500         * Loop over leaf entries with the right hash value.
 501         */
 502        for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
 503                                be32_to_cpu(lep->hashval) == args->hashval;
 504                                lep++, index++) {
 505                /*
 506                 * Skip stale leaf entries.
 507                 */
 508                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 509                        continue;
 510                /*
 511                 * Pull the data block number from the entry.
 512                 */
 513                newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 514                /*
 515                 * Not adding a new entry, so we really want to find
 516                 * the name given to us.
 517                 *
 518                 * If it's a different data block, go get it.
 519                 */
 520                if (newdb != curdb) {
 521                        /*
 522                         * If we had a block before that we aren't saving
 523                         * for a CI name, drop it
 524                         */
 525                        if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 526                                                curdb != state->extrablk.blkno))
 527                                xfs_trans_brelse(tp, curbp);
 528                        /*
 529                         * If needing the block that is saved with a CI match,
 530                         * use it otherwise read in the new data block.
 531                         */
 532                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 533                                        newdb == state->extrablk.blkno) {
 534                                ASSERT(state->extravalid);
 535                                curbp = state->extrablk.bp;
 536                        } else {
 537                                error = xfs_da_read_buf(tp, dp,
 538                                                xfs_dir2_db_to_da(mp, newdb),
 539                                                -1, &curbp, XFS_DATA_FORK);
 540                                if (error)
 541                                        return error;
 542                        }
 543                        xfs_dir2_data_check(dp, curbp);
 544                        curdb = newdb;
 545                }
 546                /*
 547                 * Point to the data entry.
 548                 */
 549                dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr +
 550                        xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
 551                /*
 552                 * Compare the entry and if it's an exact match, return
 553                 * EEXIST immediately. If it's the first case-insensitive
 554                 * match, store the block & inode number and continue looking.
 555                 */
 556                cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 557                if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 558                        /* If there is a CI match block, drop it */
 559                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 560                                                curdb != state->extrablk.blkno)
 561                                xfs_trans_brelse(tp, state->extrablk.bp);
 562                        args->cmpresult = cmp;
 563                        args->inumber = be64_to_cpu(dep->inumber);
 564                        *indexp = index;
 565                        state->extravalid = 1;
 566                        state->extrablk.bp = curbp;
 567                        state->extrablk.blkno = curdb;
 568                        state->extrablk.index = (int)((char *)dep -
 569                                                        (char *)curbp->b_addr);
 570                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 571                        if (cmp == XFS_CMP_EXACT)
 572                                return XFS_ERROR(EEXIST);
 573                }
 574        }
 575        ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
 576                                        (args->op_flags & XFS_DA_OP_OKNOENT));
 577        if (curbp) {
 578                if (args->cmpresult == XFS_CMP_DIFFERENT) {
 579                        /* Giving back last used data block. */
 580                        state->extravalid = 1;
 581                        state->extrablk.bp = curbp;
 582                        state->extrablk.index = -1;
 583                        state->extrablk.blkno = curdb;
 584                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 585                } else {
 586                        /* If the curbp is not the CI match block, drop it */
 587                        if (state->extrablk.bp != curbp)
 588                                xfs_trans_brelse(tp, curbp);
 589                }
 590        } else {
 591                state->extravalid = 0;
 592        }
 593        *indexp = index;
 594        return XFS_ERROR(ENOENT);
 595}
 596
 597/*
 598 * Look up a leaf entry in a node-format leaf block.
 599 * If this is an addname then the extrablk in state is a freespace block,
 600 * otherwise it's a data block.
 601 */
 602int
 603xfs_dir2_leafn_lookup_int(
 604        struct xfs_buf          *bp,            /* leaf buffer */
 605        xfs_da_args_t           *args,          /* operation arguments */
 606        int                     *indexp,        /* out: leaf entry index */
 607        xfs_da_state_t          *state)         /* state to fill in */
 608{
 609        if (args->op_flags & XFS_DA_OP_ADDNAME)
 610                return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 611                                                        state);
 612        return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 613}
 614
 615/*
 616 * Move count leaf entries from source to destination leaf.
 617 * Log entries and headers.  Stale entries are preserved.
 618 */
 619static void
 620xfs_dir2_leafn_moveents(
 621        xfs_da_args_t   *args,                  /* operation arguments */
 622        struct xfs_buf  *bp_s,                  /* source leaf buffer */
 623        int             start_s,                /* source leaf index */
 624        struct xfs_buf  *bp_d,                  /* destination leaf buffer */
 625        int             start_d,                /* destination leaf index */
 626        int             count)                  /* count of leaves to copy */
 627{
 628        xfs_dir2_leaf_t *leaf_d;                /* destination leaf structure */
 629        xfs_dir2_leaf_t *leaf_s;                /* source leaf structure */
 630        int             stale;                  /* count stale leaves copied */
 631        xfs_trans_t     *tp;                    /* transaction pointer */
 632
 633        trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 634
 635        /*
 636         * Silently return if nothing to do.
 637         */
 638        if (count == 0) {
 639                return;
 640        }
 641        tp = args->trans;
 642        leaf_s = bp_s->b_addr;
 643        leaf_d = bp_d->b_addr;
 644        /*
 645         * If the destination index is not the end of the current
 646         * destination leaf entries, open up a hole in the destination
 647         * to hold the new entries.
 648         */
 649        if (start_d < be16_to_cpu(leaf_d->hdr.count)) {
 650                memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
 651                        (be16_to_cpu(leaf_d->hdr.count) - start_d) *
 652                        sizeof(xfs_dir2_leaf_entry_t));
 653                xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
 654                        count + be16_to_cpu(leaf_d->hdr.count) - 1);
 655        }
 656        /*
 657         * If the source has stale leaves, count the ones in the copy range
 658         * so we can update the header correctly.
 659         */
 660        if (leaf_s->hdr.stale) {
 661                int     i;                      /* temp leaf index */
 662
 663                for (i = start_s, stale = 0; i < start_s + count; i++) {
 664                        if (leaf_s->ents[i].address ==
 665                            cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 666                                stale++;
 667                }
 668        } else
 669                stale = 0;
 670        /*
 671         * Copy the leaf entries from source to destination.
 672         */
 673        memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
 674                count * sizeof(xfs_dir2_leaf_entry_t));
 675        xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 676        /*
 677         * If there are source entries after the ones we copied,
 678         * delete the ones we copied by sliding the next ones down.
 679         */
 680        if (start_s + count < be16_to_cpu(leaf_s->hdr.count)) {
 681                memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
 682                        count * sizeof(xfs_dir2_leaf_entry_t));
 683                xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 684        }
 685        /*
 686         * Update the headers and log them.
 687         */
 688        be16_add_cpu(&leaf_s->hdr.count, -(count));
 689        be16_add_cpu(&leaf_s->hdr.stale, -(stale));
 690        be16_add_cpu(&leaf_d->hdr.count, count);
 691        be16_add_cpu(&leaf_d->hdr.stale, stale);
 692        xfs_dir2_leaf_log_header(tp, bp_s);
 693        xfs_dir2_leaf_log_header(tp, bp_d);
 694        xfs_dir2_leafn_check(args->dp, bp_s);
 695        xfs_dir2_leafn_check(args->dp, bp_d);
 696}
 697
 698/*
 699 * Determine the sort order of two leaf blocks.
 700 * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 701 */
 702int                                             /* sort order */
 703xfs_dir2_leafn_order(
 704        struct xfs_buf  *leaf1_bp,              /* leaf1 buffer */
 705        struct xfs_buf  *leaf2_bp)              /* leaf2 buffer */
 706{
 707        xfs_dir2_leaf_t *leaf1;                 /* leaf1 structure */
 708        xfs_dir2_leaf_t *leaf2;                 /* leaf2 structure */
 709
 710        leaf1 = leaf1_bp->b_addr;
 711        leaf2 = leaf2_bp->b_addr;
 712        ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 713        ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 714        if (be16_to_cpu(leaf1->hdr.count) > 0 &&
 715            be16_to_cpu(leaf2->hdr.count) > 0 &&
 716            (be32_to_cpu(leaf2->ents[0].hashval) < be32_to_cpu(leaf1->ents[0].hashval) ||
 717             be32_to_cpu(leaf2->ents[be16_to_cpu(leaf2->hdr.count) - 1].hashval) <
 718             be32_to_cpu(leaf1->ents[be16_to_cpu(leaf1->hdr.count) - 1].hashval)))
 719                return 1;
 720        return 0;
 721}
 722
 723/*
 724 * Rebalance leaf entries between two leaf blocks.
 725 * This is actually only called when the second block is new,
 726 * though the code deals with the general case.
 727 * A new entry will be inserted in one of the blocks, and that
 728 * entry is taken into account when balancing.
 729 */
 730static void
 731xfs_dir2_leafn_rebalance(
 732        xfs_da_state_t          *state,         /* btree cursor */
 733        xfs_da_state_blk_t      *blk1,          /* first btree block */
 734        xfs_da_state_blk_t      *blk2)          /* second btree block */
 735{
 736        xfs_da_args_t           *args;          /* operation arguments */
 737        int                     count;          /* count (& direction) leaves */
 738        int                     isleft;         /* new goes in left leaf */
 739        xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 740        xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
 741        int                     mid;            /* midpoint leaf index */
 742#ifdef DEBUG
 743        int                     oldstale;       /* old count of stale leaves */
 744#endif
 745        int                     oldsum;         /* old total leaf count */
 746        int                     swap;           /* swapped leaf blocks */
 747
 748        args = state->args;
 749        /*
 750         * If the block order is wrong, swap the arguments.
 751         */
 752        if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
 753                xfs_da_state_blk_t      *tmp;   /* temp for block swap */
 754
 755                tmp = blk1;
 756                blk1 = blk2;
 757                blk2 = tmp;
 758        }
 759        leaf1 = blk1->bp->b_addr;
 760        leaf2 = blk2->bp->b_addr;
 761        oldsum = be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count);
 762#ifdef DEBUG
 763        oldstale = be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale);
 764#endif
 765        mid = oldsum >> 1;
 766        /*
 767         * If the old leaf count was odd then the new one will be even,
 768         * so we need to divide the new count evenly.
 769         */
 770        if (oldsum & 1) {
 771                xfs_dahash_t    midhash;        /* middle entry hash value */
 772
 773                if (mid >= be16_to_cpu(leaf1->hdr.count))
 774                        midhash = be32_to_cpu(leaf2->ents[mid - be16_to_cpu(leaf1->hdr.count)].hashval);
 775                else
 776                        midhash = be32_to_cpu(leaf1->ents[mid].hashval);
 777                isleft = args->hashval <= midhash;
 778        }
 779        /*
 780         * If the old count is even then the new count is odd, so there's
 781         * no preferred side for the new entry.
 782         * Pick the left one.
 783         */
 784        else
 785                isleft = 1;
 786        /*
 787         * Calculate moved entry count.  Positive means left-to-right,
 788         * negative means right-to-left.  Then move the entries.
 789         */
 790        count = be16_to_cpu(leaf1->hdr.count) - mid + (isleft == 0);
 791        if (count > 0)
 792                xfs_dir2_leafn_moveents(args, blk1->bp,
 793                        be16_to_cpu(leaf1->hdr.count) - count, blk2->bp, 0, count);
 794        else if (count < 0)
 795                xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
 796                        be16_to_cpu(leaf1->hdr.count), count);
 797        ASSERT(be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count) == oldsum);
 798        ASSERT(be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale) == oldstale);
 799        /*
 800         * Mark whether we're inserting into the old or new leaf.
 801         */
 802        if (be16_to_cpu(leaf1->hdr.count) < be16_to_cpu(leaf2->hdr.count))
 803                state->inleaf = swap;
 804        else if (be16_to_cpu(leaf1->hdr.count) > be16_to_cpu(leaf2->hdr.count))
 805                state->inleaf = !swap;
 806        else
 807                state->inleaf =
 808                        swap ^ (blk1->index <= be16_to_cpu(leaf1->hdr.count));
 809        /*
 810         * Adjust the expected index for insertion.
 811         */
 812        if (!state->inleaf)
 813                blk2->index = blk1->index - be16_to_cpu(leaf1->hdr.count);
 814
 815        /*
 816         * Finally sanity check just to make sure we are not returning a
 817         * negative index
 818         */
 819        if(blk2->index < 0) {
 820                state->inleaf = 1;
 821                blk2->index = 0;
 822                xfs_alert(args->dp->i_mount,
 823        "%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
 824                        __func__, blk1->index);
 825        }
 826}
 827
 828/*
 829 * Remove an entry from a node directory.
 830 * This removes the leaf entry and the data entry,
 831 * and updates the free block if necessary.
 832 */
 833static int                                      /* error */
 834xfs_dir2_leafn_remove(
 835        xfs_da_args_t           *args,          /* operation arguments */
 836        struct xfs_buf          *bp,            /* leaf buffer */
 837        int                     index,          /* leaf entry index */
 838        xfs_da_state_blk_t      *dblk,          /* data block */
 839        int                     *rval)          /* resulting block needs join */
 840{
 841        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 842        xfs_dir2_db_t           db;             /* data block number */
 843        struct xfs_buf          *dbp;           /* data block buffer */
 844        xfs_dir2_data_entry_t   *dep;           /* data block entry */
 845        xfs_inode_t             *dp;            /* incore directory inode */
 846        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 847        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 848        int                     longest;        /* longest data free entry */
 849        int                     off;            /* data block entry offset */
 850        xfs_mount_t             *mp;            /* filesystem mount point */
 851        int                     needlog;        /* need to log data header */
 852        int                     needscan;       /* need to rescan data frees */
 853        xfs_trans_t             *tp;            /* transaction pointer */
 854
 855        trace_xfs_dir2_leafn_remove(args, index);
 856
 857        dp = args->dp;
 858        tp = args->trans;
 859        mp = dp->i_mount;
 860        leaf = bp->b_addr;
 861        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
 862        /*
 863         * Point to the entry we're removing.
 864         */
 865        lep = &leaf->ents[index];
 866        /*
 867         * Extract the data block and offset from the entry.
 868         */
 869        db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 870        ASSERT(dblk->blkno == db);
 871        off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
 872        ASSERT(dblk->index == off);
 873        /*
 874         * Kill the leaf entry by marking it stale.
 875         * Log the leaf block changes.
 876         */
 877        be16_add_cpu(&leaf->hdr.stale, 1);
 878        xfs_dir2_leaf_log_header(tp, bp);
 879        lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
 880        xfs_dir2_leaf_log_ents(tp, bp, index, index);
 881        /*
 882         * Make the data entry free.  Keep track of the longest freespace
 883         * in the data block in case it changes.
 884         */
 885        dbp = dblk->bp;
 886        hdr = dbp->b_addr;
 887        dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
 888        longest = be16_to_cpu(hdr->bestfree[0].length);
 889        needlog = needscan = 0;
 890        xfs_dir2_data_make_free(tp, dbp, off,
 891                xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
 892        /*
 893         * Rescan the data block freespaces for bestfree.
 894         * Log the data block header if needed.
 895         */
 896        if (needscan)
 897                xfs_dir2_data_freescan(mp, hdr, &needlog);
 898        if (needlog)
 899                xfs_dir2_data_log_header(tp, dbp);
 900        xfs_dir2_data_check(dp, dbp);
 901        /*
 902         * If the longest data block freespace changes, need to update
 903         * the corresponding freeblock entry.
 904         */
 905        if (longest < be16_to_cpu(hdr->bestfree[0].length)) {
 906                int             error;          /* error return value */
 907                struct xfs_buf  *fbp;           /* freeblock buffer */
 908                xfs_dir2_db_t   fdb;            /* freeblock block number */
 909                int             findex;         /* index in freeblock entries */
 910                xfs_dir2_free_t *free;          /* freeblock structure */
 911                int             logfree;        /* need to log free entry */
 912
 913                /*
 914                 * Convert the data block number to a free block,
 915                 * read in the free block.
 916                 */
 917                fdb = xfs_dir2_db_to_fdb(mp, db);
 918                if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb),
 919                                -1, &fbp, XFS_DATA_FORK))) {
 920                        return error;
 921                }
 922                free = fbp->b_addr;
 923                ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
 924                ASSERT(be32_to_cpu(free->hdr.firstdb) ==
 925                       xfs_dir2_free_max_bests(mp) *
 926                       (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
 927                /*
 928                 * Calculate which entry we need to fix.
 929                 */
 930                findex = xfs_dir2_db_to_fdindex(mp, db);
 931                longest = be16_to_cpu(hdr->bestfree[0].length);
 932                /*
 933                 * If the data block is now empty we can get rid of it
 934                 * (usually).
 935                 */
 936                if (longest == mp->m_dirblksize - (uint)sizeof(*hdr)) {
 937                        /*
 938                         * Try to punch out the data block.
 939                         */
 940                        error = xfs_dir2_shrink_inode(args, db, dbp);
 941                        if (error == 0) {
 942                                dblk->bp = NULL;
 943                                hdr = NULL;
 944                        }
 945                        /*
 946                         * We can get ENOSPC if there's no space reservation.
 947                         * In this case just drop the buffer and some one else
 948                         * will eventually get rid of the empty block.
 949                         */
 950                        else if (!(error == ENOSPC && args->total == 0))
 951                                return error;
 952                }
 953                /*
 954                 * If we got rid of the data block, we can eliminate that entry
 955                 * in the free block.
 956                 */
 957                if (hdr == NULL) {
 958                        /*
 959                         * One less used entry in the free table.
 960                         */
 961                        be32_add_cpu(&free->hdr.nused, -1);
 962                        xfs_dir2_free_log_header(tp, fbp);
 963                        /*
 964                         * If this was the last entry in the table, we can
 965                         * trim the table size back.  There might be other
 966                         * entries at the end referring to non-existent
 967                         * data blocks, get those too.
 968                         */
 969                        if (findex == be32_to_cpu(free->hdr.nvalid) - 1) {
 970                                int     i;              /* free entry index */
 971
 972                                for (i = findex - 1;
 973                                     i >= 0 &&
 974                                     free->bests[i] == cpu_to_be16(NULLDATAOFF);
 975                                     i--)
 976                                        continue;
 977                                free->hdr.nvalid = cpu_to_be32(i + 1);
 978                                logfree = 0;
 979                        }
 980                        /*
 981                         * Not the last entry, just punch it out.
 982                         */
 983                        else {
 984                                free->bests[findex] = cpu_to_be16(NULLDATAOFF);
 985                                logfree = 1;
 986                        }
 987                        /*
 988                         * If there are no useful entries left in the block,
 989                         * get rid of the block if we can.
 990                         */
 991                        if (!free->hdr.nused) {
 992                                error = xfs_dir2_shrink_inode(args, fdb, fbp);
 993                                if (error == 0) {
 994                                        fbp = NULL;
 995                                        logfree = 0;
 996                                } else if (error != ENOSPC || args->total != 0)
 997                                        return error;
 998                                /*
 999                                 * It's possible to get ENOSPC if there is no
1000                                 * space reservation.  In this case some one
1001                                 * else will eventually get rid of this block.
1002                                 */
1003                        }
1004                }
1005                /*
1006                 * Data block is not empty, just set the free entry to
1007                 * the new value.
1008                 */
1009                else {
1010                        free->bests[findex] = cpu_to_be16(longest);
1011                        logfree = 1;
1012                }
1013                /*
1014                 * Log the free entry that changed, unless we got rid of it.
1015                 */
1016                if (logfree)
1017                        xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1018        }
1019        xfs_dir2_leafn_check(dp, bp);
1020        /*
1021         * Return indication of whether this leaf block is empty enough
1022         * to justify trying to join it with a neighbor.
1023         */
1024        *rval =
1025                ((uint)sizeof(leaf->hdr) +
1026                 (uint)sizeof(leaf->ents[0]) *
1027                 (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale))) <
1028                mp->m_dir_magicpct;
1029        return 0;
1030}
1031
1032/*
1033 * Split the leaf entries in the old block into old and new blocks.
1034 */
1035int                                             /* error */
1036xfs_dir2_leafn_split(
1037        xfs_da_state_t          *state,         /* btree cursor */
1038        xfs_da_state_blk_t      *oldblk,        /* original block */
1039        xfs_da_state_blk_t      *newblk)        /* newly created block */
1040{
1041        xfs_da_args_t           *args;          /* operation arguments */
1042        xfs_dablk_t             blkno;          /* new leaf block number */
1043        int                     error;          /* error return value */
1044        xfs_mount_t             *mp;            /* filesystem mount point */
1045
1046        /*
1047         * Allocate space for a new leaf node.
1048         */
1049        args = state->args;
1050        mp = args->dp->i_mount;
1051        ASSERT(args != NULL);
1052        ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1053        error = xfs_da_grow_inode(args, &blkno);
1054        if (error) {
1055                return error;
1056        }
1057        /*
1058         * Initialize the new leaf block.
1059         */
1060        error = xfs_dir2_leaf_init(args, xfs_dir2_da_to_db(mp, blkno),
1061                &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1062        if (error) {
1063                return error;
1064        }
1065        newblk->blkno = blkno;
1066        newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1067        /*
1068         * Rebalance the entries across the two leaves, link the new
1069         * block into the leaves.
1070         */
1071        xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1072        error = xfs_da_blk_link(state, oldblk, newblk);
1073        if (error) {
1074                return error;
1075        }
1076        /*
1077         * Insert the new entry in the correct block.
1078         */
1079        if (state->inleaf)
1080                error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1081        else
1082                error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1083        /*
1084         * Update last hashval in each block since we added the name.
1085         */
1086        oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1087        newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1088        xfs_dir2_leafn_check(args->dp, oldblk->bp);
1089        xfs_dir2_leafn_check(args->dp, newblk->bp);
1090        return error;
1091}
1092
1093/*
1094 * Check a leaf block and its neighbors to see if the block should be
1095 * collapsed into one or the other neighbor.  Always keep the block
1096 * with the smaller block number.
1097 * If the current block is over 50% full, don't try to join it, return 0.
1098 * If the block is empty, fill in the state structure and return 2.
1099 * If it can be collapsed, fill in the state structure and return 1.
1100 * If nothing can be done, return 0.
1101 */
1102int                                             /* error */
1103xfs_dir2_leafn_toosmall(
1104        xfs_da_state_t          *state,         /* btree cursor */
1105        int                     *action)        /* resulting action to take */
1106{
1107        xfs_da_state_blk_t      *blk;           /* leaf block */
1108        xfs_dablk_t             blkno;          /* leaf block number */
1109        struct xfs_buf          *bp;            /* leaf buffer */
1110        int                     bytes;          /* bytes in use */
1111        int                     count;          /* leaf live entry count */
1112        int                     error;          /* error return value */
1113        int                     forward;        /* sibling block direction */
1114        int                     i;              /* sibling counter */
1115        xfs_da_blkinfo_t        *info;          /* leaf block header */
1116        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1117        int                     rval;           /* result from path_shift */
1118
1119        /*
1120         * Check for the degenerate case of the block being over 50% full.
1121         * If so, it's not worth even looking to see if we might be able
1122         * to coalesce with a sibling.
1123         */
1124        blk = &state->path.blk[state->path.active - 1];
1125        info = blk->bp->b_addr;
1126        ASSERT(info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1127        leaf = (xfs_dir2_leaf_t *)info;
1128        count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1129        bytes = (uint)sizeof(leaf->hdr) + count * (uint)sizeof(leaf->ents[0]);
1130        if (bytes > (state->blocksize >> 1)) {
1131                /*
1132                 * Blk over 50%, don't try to join.
1133                 */
1134                *action = 0;
1135                return 0;
1136        }
1137        /*
1138         * Check for the degenerate case of the block being empty.
1139         * If the block is empty, we'll simply delete it, no need to
1140         * coalesce it with a sibling block.  We choose (arbitrarily)
1141         * to merge with the forward block unless it is NULL.
1142         */
1143        if (count == 0) {
1144                /*
1145                 * Make altpath point to the block we want to keep and
1146                 * path point to the block we want to drop (this one).
1147                 */
1148                forward = (info->forw != 0);
1149                memcpy(&state->altpath, &state->path, sizeof(state->path));
1150                error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1151                        &rval);
1152                if (error)
1153                        return error;
1154                *action = rval ? 2 : 0;
1155                return 0;
1156        }
1157        /*
1158         * Examine each sibling block to see if we can coalesce with
1159         * at least 25% free space to spare.  We need to figure out
1160         * whether to merge with the forward or the backward block.
1161         * We prefer coalescing with the lower numbered sibling so as
1162         * to shrink a directory over time.
1163         */
1164        forward = be32_to_cpu(info->forw) < be32_to_cpu(info->back);
1165        for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1166                blkno = forward ? be32_to_cpu(info->forw) : be32_to_cpu(info->back);
1167                if (blkno == 0)
1168                        continue;
1169                /*
1170                 * Read the sibling leaf block.
1171                 */
1172                if ((error =
1173                    xfs_da_read_buf(state->args->trans, state->args->dp, blkno,
1174                            -1, &bp, XFS_DATA_FORK))) {
1175                        return error;
1176                }
1177                ASSERT(bp != NULL);
1178                /*
1179                 * Count bytes in the two blocks combined.
1180                 */
1181                leaf = (xfs_dir2_leaf_t *)info;
1182                count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1183                bytes = state->blocksize - (state->blocksize >> 2);
1184                leaf = bp->b_addr;
1185                ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1186                count += be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1187                bytes -= count * (uint)sizeof(leaf->ents[0]);
1188                /*
1189                 * Fits with at least 25% to spare.
1190                 */
1191                if (bytes >= 0)
1192                        break;
1193                xfs_trans_brelse(state->args->trans, bp);
1194        }
1195        /*
1196         * Didn't like either block, give up.
1197         */
1198        if (i >= 2) {
1199                *action = 0;
1200                return 0;
1201        }
1202
1203        /*
1204         * Make altpath point to the block we want to keep (the lower
1205         * numbered block) and path point to the block we want to drop.
1206         */
1207        memcpy(&state->altpath, &state->path, sizeof(state->path));
1208        if (blkno < blk->blkno)
1209                error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1210                        &rval);
1211        else
1212                error = xfs_da_path_shift(state, &state->path, forward, 0,
1213                        &rval);
1214        if (error) {
1215                return error;
1216        }
1217        *action = rval ? 0 : 1;
1218        return 0;
1219}
1220
1221/*
1222 * Move all the leaf entries from drop_blk to save_blk.
1223 * This is done as part of a join operation.
1224 */
1225void
1226xfs_dir2_leafn_unbalance(
1227        xfs_da_state_t          *state,         /* cursor */
1228        xfs_da_state_blk_t      *drop_blk,      /* dead block */
1229        xfs_da_state_blk_t      *save_blk)      /* surviving block */
1230{
1231        xfs_da_args_t           *args;          /* operation arguments */
1232        xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1233        xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1234
1235        args = state->args;
1236        ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1237        ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1238        drop_leaf = drop_blk->bp->b_addr;
1239        save_leaf = save_blk->bp->b_addr;
1240        ASSERT(drop_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1241        ASSERT(save_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1242        /*
1243         * If there are any stale leaf entries, take this opportunity
1244         * to purge them.
1245         */
1246        if (drop_leaf->hdr.stale)
1247                xfs_dir2_leaf_compact(args, drop_blk->bp);
1248        if (save_leaf->hdr.stale)
1249                xfs_dir2_leaf_compact(args, save_blk->bp);
1250        /*
1251         * Move the entries from drop to the appropriate end of save.
1252         */
1253        drop_blk->hashval = be32_to_cpu(drop_leaf->ents[be16_to_cpu(drop_leaf->hdr.count) - 1].hashval);
1254        if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1255                xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp, 0,
1256                        be16_to_cpu(drop_leaf->hdr.count));
1257        else
1258                xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp,
1259                        be16_to_cpu(save_leaf->hdr.count), be16_to_cpu(drop_leaf->hdr.count));
1260        save_blk->hashval = be32_to_cpu(save_leaf->ents[be16_to_cpu(save_leaf->hdr.count) - 1].hashval);
1261        xfs_dir2_leafn_check(args->dp, save_blk->bp);
1262}
1263
1264/*
1265 * Top-level node form directory addname routine.
1266 */
1267int                                             /* error */
1268xfs_dir2_node_addname(
1269        xfs_da_args_t           *args)          /* operation arguments */
1270{
1271        xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1272        int                     error;          /* error return value */
1273        int                     rval;           /* sub-return value */
1274        xfs_da_state_t          *state;         /* btree cursor */
1275
1276        trace_xfs_dir2_node_addname(args);
1277
1278        /*
1279         * Allocate and initialize the state (btree cursor).
1280         */
1281        state = xfs_da_state_alloc();
1282        state->args = args;
1283        state->mp = args->dp->i_mount;
1284        state->blocksize = state->mp->m_dirblksize;
1285        state->node_ents = state->mp->m_dir_node_ents;
1286        /*
1287         * Look up the name.  We're not supposed to find it, but
1288         * this gives us the insertion point.
1289         */
1290        error = xfs_da_node_lookup_int(state, &rval);
1291        if (error)
1292                rval = error;
1293        if (rval != ENOENT) {
1294                goto done;
1295        }
1296        /*
1297         * Add the data entry to a data block.
1298         * Extravalid is set to a freeblock found by lookup.
1299         */
1300        rval = xfs_dir2_node_addname_int(args,
1301                state->extravalid ? &state->extrablk : NULL);
1302        if (rval) {
1303                goto done;
1304        }
1305        blk = &state->path.blk[state->path.active - 1];
1306        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1307        /*
1308         * Add the new leaf entry.
1309         */
1310        rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1311        if (rval == 0) {
1312                /*
1313                 * It worked, fix the hash values up the btree.
1314                 */
1315                if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1316                        xfs_da_fixhashpath(state, &state->path);
1317        } else {
1318                /*
1319                 * It didn't work, we need to split the leaf block.
1320                 */
1321                if (args->total == 0) {
1322                        ASSERT(rval == ENOSPC);
1323                        goto done;
1324                }
1325                /*
1326                 * Split the leaf block and insert the new entry.
1327                 */
1328                rval = xfs_da_split(state);
1329        }
1330done:
1331        xfs_da_state_free(state);
1332        return rval;
1333}
1334
1335/*
1336 * Add the data entry for a node-format directory name addition.
1337 * The leaf entry is added in xfs_dir2_leafn_add.
1338 * We may enter with a freespace block that the lookup found.
1339 */
1340static int                                      /* error */
1341xfs_dir2_node_addname_int(
1342        xfs_da_args_t           *args,          /* operation arguments */
1343        xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1344{
1345        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1346        xfs_dir2_db_t           dbno;           /* data block number */
1347        struct xfs_buf          *dbp;           /* data block buffer */
1348        xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1349        xfs_inode_t             *dp;            /* incore directory inode */
1350        xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1351        int                     error;          /* error return value */
1352        xfs_dir2_db_t           fbno;           /* freespace block number */
1353        struct xfs_buf          *fbp;           /* freespace buffer */
1354        int                     findex;         /* freespace entry index */
1355        xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1356        xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1357        xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1358        int                     length;         /* length of the new entry */
1359        int                     logfree;        /* need to log free entry */
1360        xfs_mount_t             *mp;            /* filesystem mount point */
1361        int                     needlog;        /* need to log data header */
1362        int                     needscan;       /* need to rescan data frees */
1363        __be16                  *tagp;          /* data entry tag pointer */
1364        xfs_trans_t             *tp;            /* transaction pointer */
1365
1366        dp = args->dp;
1367        mp = dp->i_mount;
1368        tp = args->trans;
1369        length = xfs_dir2_data_entsize(args->namelen);
1370        /*
1371         * If we came in with a freespace block that means that lookup
1372         * found an entry with our hash value.  This is the freespace
1373         * block for that data entry.
1374         */
1375        if (fblk) {
1376                fbp = fblk->bp;
1377                /*
1378                 * Remember initial freespace block number.
1379                 */
1380                ifbno = fblk->blkno;
1381                free = fbp->b_addr;
1382                ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1383                findex = fblk->index;
1384                /*
1385                 * This means the free entry showed that the data block had
1386                 * space for our entry, so we remembered it.
1387                 * Use that data block.
1388                 */
1389                if (findex >= 0) {
1390                        ASSERT(findex < be32_to_cpu(free->hdr.nvalid));
1391                        ASSERT(be16_to_cpu(free->bests[findex]) != NULLDATAOFF);
1392                        ASSERT(be16_to_cpu(free->bests[findex]) >= length);
1393                        dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1394                }
1395                /*
1396                 * The data block looked at didn't have enough room.
1397                 * We'll start at the beginning of the freespace entries.
1398                 */
1399                else {
1400                        dbno = -1;
1401                        findex = 0;
1402                }
1403        }
1404        /*
1405         * Didn't come in with a freespace block, so don't have a data block.
1406         */
1407        else {
1408                ifbno = dbno = -1;
1409                fbp = NULL;
1410                findex = 0;
1411        }
1412        /*
1413         * If we don't have a data block yet, we're going to scan the
1414         * freespace blocks looking for one.  Figure out what the
1415         * highest freespace block number is.
1416         */
1417        if (dbno == -1) {
1418                xfs_fileoff_t   fo;             /* freespace block number */
1419
1420                if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1421                        return error;
1422                lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1423                fbno = ifbno;
1424        }
1425        /*
1426         * While we haven't identified a data block, search the freeblock
1427         * data for a good data block.  If we find a null freeblock entry,
1428         * indicating a hole in the data blocks, remember that.
1429         */
1430        while (dbno == -1) {
1431                /*
1432                 * If we don't have a freeblock in hand, get the next one.
1433                 */
1434                if (fbp == NULL) {
1435                        /*
1436                         * Happens the first time through unless lookup gave
1437                         * us a freespace block to start with.
1438                         */
1439                        if (++fbno == 0)
1440                                fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1441                        /*
1442                         * If it's ifbno we already looked at it.
1443                         */
1444                        if (fbno == ifbno)
1445                                fbno++;
1446                        /*
1447                         * If it's off the end we're done.
1448                         */
1449                        if (fbno >= lastfbno)
1450                                break;
1451                        /*
1452                         * Read the block.  There can be holes in the
1453                         * freespace blocks, so this might not succeed.
1454                         * This should be really rare, so there's no reason
1455                         * to avoid it.
1456                         */
1457                        if ((error = xfs_da_read_buf(tp, dp,
1458                                        xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1459                                        XFS_DATA_FORK))) {
1460                                return error;
1461                        }
1462                        if (unlikely(fbp == NULL)) {
1463                                continue;
1464                        }
1465                        free = fbp->b_addr;
1466                        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1467                        findex = 0;
1468                }
1469                /*
1470                 * Look at the current free entry.  Is it good enough?
1471                 */
1472                if (be16_to_cpu(free->bests[findex]) != NULLDATAOFF &&
1473                    be16_to_cpu(free->bests[findex]) >= length)
1474                        dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1475                else {
1476                        /*
1477                         * Are we done with the freeblock?
1478                         */
1479                        if (++findex == be32_to_cpu(free->hdr.nvalid)) {
1480                                /*
1481                                 * Drop the block.
1482                                 */
1483                                xfs_trans_brelse(tp, fbp);
1484                                fbp = NULL;
1485                                if (fblk && fblk->bp)
1486                                        fblk->bp = NULL;
1487                        }
1488                }
1489        }
1490        /*
1491         * If we don't have a data block, we need to allocate one and make
1492         * the freespace entries refer to it.
1493         */
1494        if (unlikely(dbno == -1)) {
1495                /*
1496                 * Not allowed to allocate, return failure.
1497                 */
1498                if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
1499                        return XFS_ERROR(ENOSPC);
1500
1501                /*
1502                 * Allocate and initialize the new data block.
1503                 */
1504                if (unlikely((error = xfs_dir2_grow_inode(args,
1505                                                         XFS_DIR2_DATA_SPACE,
1506                                                         &dbno)) ||
1507                    (error = xfs_dir2_data_init(args, dbno, &dbp))))
1508                        return error;
1509
1510                /*
1511                 * If (somehow) we have a freespace block, get rid of it.
1512                 */
1513                if (fbp)
1514                        xfs_trans_brelse(tp, fbp);
1515                if (fblk && fblk->bp)
1516                        fblk->bp = NULL;
1517
1518                /*
1519                 * Get the freespace block corresponding to the data block
1520                 * that was just allocated.
1521                 */
1522                fbno = xfs_dir2_db_to_fdb(mp, dbno);
1523                if (unlikely(error = xfs_da_read_buf(tp, dp,
1524                                xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1525                                XFS_DATA_FORK)))
1526                        return error;
1527
1528                /*
1529                 * If there wasn't a freespace block, the read will
1530                 * return a NULL fbp.  Allocate and initialize a new one.
1531                 */
1532                if( fbp == NULL ) {
1533                        if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1534                                                        &fbno))) {
1535                                return error;
1536                        }
1537
1538                        if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1539                                xfs_alert(mp,
1540                        "%s: dir ino %llu needed freesp block %lld for\n"
1541                        "  data block %lld, got %lld ifbno %llu lastfbno %d",
1542                                        __func__, (unsigned long long)dp->i_ino,
1543                                        (long long)xfs_dir2_db_to_fdb(mp, dbno),
1544                                        (long long)dbno, (long long)fbno,
1545                                        (unsigned long long)ifbno, lastfbno);
1546                                if (fblk) {
1547                                        xfs_alert(mp,
1548                                " fblk 0x%p blkno %llu index %d magic 0x%x",
1549                                                fblk,
1550                                                (unsigned long long)fblk->blkno,
1551                                                fblk->index,
1552                                                fblk->magic);
1553                                } else {
1554                                        xfs_alert(mp, " ... fblk is NULL");
1555                                }
1556                                XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1557                                                 XFS_ERRLEVEL_LOW, mp);
1558                                return XFS_ERROR(EFSCORRUPTED);
1559                        }
1560
1561                        /*
1562                         * Get a buffer for the new block.
1563                         */
1564                        if ((error = xfs_da_get_buf(tp, dp,
1565                                                   xfs_dir2_db_to_da(mp, fbno),
1566                                                   -1, &fbp, XFS_DATA_FORK))) {
1567                                return error;
1568                        }
1569                        ASSERT(fbp != NULL);
1570
1571                        /*
1572                         * Initialize the new block to be empty, and remember
1573                         * its first slot as our empty slot.
1574                         */
1575                        free = fbp->b_addr;
1576                        free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
1577                        free->hdr.firstdb = cpu_to_be32(
1578                                (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1579                                xfs_dir2_free_max_bests(mp));
1580                        free->hdr.nvalid = 0;
1581                        free->hdr.nused = 0;
1582                } else {
1583                        free = fbp->b_addr;
1584                        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1585                }
1586
1587                /*
1588                 * Set the freespace block index from the data block number.
1589                 */
1590                findex = xfs_dir2_db_to_fdindex(mp, dbno);
1591                /*
1592                 * If it's after the end of the current entries in the
1593                 * freespace block, extend that table.
1594                 */
1595                if (findex >= be32_to_cpu(free->hdr.nvalid)) {
1596                        ASSERT(findex < xfs_dir2_free_max_bests(mp));
1597                        free->hdr.nvalid = cpu_to_be32(findex + 1);
1598                        /*
1599                         * Tag new entry so nused will go up.
1600                         */
1601                        free->bests[findex] = cpu_to_be16(NULLDATAOFF);
1602                }
1603                /*
1604                 * If this entry was for an empty data block
1605                 * (this should always be true) then update the header.
1606                 */
1607                if (free->bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1608                        be32_add_cpu(&free->hdr.nused, 1);
1609                        xfs_dir2_free_log_header(tp, fbp);
1610                }
1611                /*
1612                 * Update the real value in the table.
1613                 * We haven't allocated the data entry yet so this will
1614                 * change again.
1615                 */
1616                hdr = dbp->b_addr;
1617                free->bests[findex] = hdr->bestfree[0].length;
1618                logfree = 1;
1619        }
1620        /*
1621         * We had a data block so we don't have to make a new one.
1622         */
1623        else {
1624                /*
1625                 * If just checking, we succeeded.
1626                 */
1627                if (args->op_flags & XFS_DA_OP_JUSTCHECK)
1628                        return 0;
1629
1630                /*
1631                 * Read the data block in.
1632                 */
1633                error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1634                                -1, &dbp, XFS_DATA_FORK);
1635                if (error)
1636                        return error;
1637                hdr = dbp->b_addr;
1638                logfree = 0;
1639        }
1640        ASSERT(be16_to_cpu(hdr->bestfree[0].length) >= length);
1641        /*
1642         * Point to the existing unused space.
1643         */
1644        dup = (xfs_dir2_data_unused_t *)
1645              ((char *)hdr + be16_to_cpu(hdr->bestfree[0].offset));
1646        needscan = needlog = 0;
1647        /*
1648         * Mark the first part of the unused space, inuse for us.
1649         */
1650        xfs_dir2_data_use_free(tp, dbp, dup,
1651                (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
1652                &needlog, &needscan);
1653        /*
1654         * Fill in the new entry and log it.
1655         */
1656        dep = (xfs_dir2_data_entry_t *)dup;
1657        dep->inumber = cpu_to_be64(args->inumber);
1658        dep->namelen = args->namelen;
1659        memcpy(dep->name, args->name, dep->namelen);
1660        tagp = xfs_dir2_data_entry_tag_p(dep);
1661        *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1662        xfs_dir2_data_log_entry(tp, dbp, dep);
1663        /*
1664         * Rescan the block for bestfree if needed.
1665         */
1666        if (needscan)
1667                xfs_dir2_data_freescan(mp, hdr, &needlog);
1668        /*
1669         * Log the data block header if needed.
1670         */
1671        if (needlog)
1672                xfs_dir2_data_log_header(tp, dbp);
1673        /*
1674         * If the freespace entry is now wrong, update it.
1675         */
1676        if (be16_to_cpu(free->bests[findex]) != be16_to_cpu(hdr->bestfree[0].length)) {
1677                free->bests[findex] = hdr->bestfree[0].length;
1678                logfree = 1;
1679        }
1680        /*
1681         * Log the freespace entry if needed.
1682         */
1683        if (logfree)
1684                xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1685        /*
1686         * Return the data block and offset in args, then drop the data block.
1687         */
1688        args->blkno = (xfs_dablk_t)dbno;
1689        args->index = be16_to_cpu(*tagp);
1690        return 0;
1691}
1692
1693/*
1694 * Lookup an entry in a node-format directory.
1695 * All the real work happens in xfs_da_node_lookup_int.
1696 * The only real output is the inode number of the entry.
1697 */
1698int                                             /* error */
1699xfs_dir2_node_lookup(
1700        xfs_da_args_t   *args)                  /* operation arguments */
1701{
1702        int             error;                  /* error return value */
1703        int             i;                      /* btree level */
1704        int             rval;                   /* operation return value */
1705        xfs_da_state_t  *state;                 /* btree cursor */
1706
1707        trace_xfs_dir2_node_lookup(args);
1708
1709        /*
1710         * Allocate and initialize the btree cursor.
1711         */
1712        state = xfs_da_state_alloc();
1713        state->args = args;
1714        state->mp = args->dp->i_mount;
1715        state->blocksize = state->mp->m_dirblksize;
1716        state->node_ents = state->mp->m_dir_node_ents;
1717        /*
1718         * Fill in the path to the entry in the cursor.
1719         */
1720        error = xfs_da_node_lookup_int(state, &rval);
1721        if (error)
1722                rval = error;
1723        else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
1724                /* If a CI match, dup the actual name and return EEXIST */
1725                xfs_dir2_data_entry_t   *dep;
1726
1727                dep = (xfs_dir2_data_entry_t *)
1728                        ((char *)state->extrablk.bp->b_addr +
1729                                                 state->extrablk.index);
1730                rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1731        }
1732        /*
1733         * Release the btree blocks and leaf block.
1734         */
1735        for (i = 0; i < state->path.active; i++) {
1736                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1737                state->path.blk[i].bp = NULL;
1738        }
1739        /*
1740         * Release the data block if we have it.
1741         */
1742        if (state->extravalid && state->extrablk.bp) {
1743                xfs_trans_brelse(args->trans, state->extrablk.bp);
1744                state->extrablk.bp = NULL;
1745        }
1746        xfs_da_state_free(state);
1747        return rval;
1748}
1749
1750/*
1751 * Remove an entry from a node-format directory.
1752 */
1753int                                             /* error */
1754xfs_dir2_node_removename(
1755        xfs_da_args_t           *args)          /* operation arguments */
1756{
1757        xfs_da_state_blk_t      *blk;           /* leaf block */
1758        int                     error;          /* error return value */
1759        int                     rval;           /* operation return value */
1760        xfs_da_state_t          *state;         /* btree cursor */
1761
1762        trace_xfs_dir2_node_removename(args);
1763
1764        /*
1765         * Allocate and initialize the btree cursor.
1766         */
1767        state = xfs_da_state_alloc();
1768        state->args = args;
1769        state->mp = args->dp->i_mount;
1770        state->blocksize = state->mp->m_dirblksize;
1771        state->node_ents = state->mp->m_dir_node_ents;
1772        /*
1773         * Look up the entry we're deleting, set up the cursor.
1774         */
1775        error = xfs_da_node_lookup_int(state, &rval);
1776        if (error)
1777                rval = error;
1778        /*
1779         * Didn't find it, upper layer screwed up.
1780         */
1781        if (rval != EEXIST) {
1782                xfs_da_state_free(state);
1783                return rval;
1784        }
1785        blk = &state->path.blk[state->path.active - 1];
1786        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1787        ASSERT(state->extravalid);
1788        /*
1789         * Remove the leaf and data entries.
1790         * Extrablk refers to the data block.
1791         */
1792        error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
1793                &state->extrablk, &rval);
1794        if (error)
1795                return error;
1796        /*
1797         * Fix the hash values up the btree.
1798         */
1799        xfs_da_fixhashpath(state, &state->path);
1800        /*
1801         * If we need to join leaf blocks, do it.
1802         */
1803        if (rval && state->path.active > 1)
1804                error = xfs_da_join(state);
1805        /*
1806         * If no errors so far, try conversion to leaf format.
1807         */
1808        if (!error)
1809                error = xfs_dir2_node_to_leaf(state);
1810        xfs_da_state_free(state);
1811        return error;
1812}
1813
1814/*
1815 * Replace an entry's inode number in a node-format directory.
1816 */
1817int                                             /* error */
1818xfs_dir2_node_replace(
1819        xfs_da_args_t           *args)          /* operation arguments */
1820{
1821        xfs_da_state_blk_t      *blk;           /* leaf block */
1822        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1823        xfs_dir2_data_entry_t   *dep;           /* data entry changed */
1824        int                     error;          /* error return value */
1825        int                     i;              /* btree level */
1826        xfs_ino_t               inum;           /* new inode number */
1827        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1828        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
1829        int                     rval;           /* internal return value */
1830        xfs_da_state_t          *state;         /* btree cursor */
1831
1832        trace_xfs_dir2_node_replace(args);
1833
1834        /*
1835         * Allocate and initialize the btree cursor.
1836         */
1837        state = xfs_da_state_alloc();
1838        state->args = args;
1839        state->mp = args->dp->i_mount;
1840        state->blocksize = state->mp->m_dirblksize;
1841        state->node_ents = state->mp->m_dir_node_ents;
1842        inum = args->inumber;
1843        /*
1844         * Lookup the entry to change in the btree.
1845         */
1846        error = xfs_da_node_lookup_int(state, &rval);
1847        if (error) {
1848                rval = error;
1849        }
1850        /*
1851         * It should be found, since the vnodeops layer has looked it up
1852         * and locked it.  But paranoia is good.
1853         */
1854        if (rval == EEXIST) {
1855                /*
1856                 * Find the leaf entry.
1857                 */
1858                blk = &state->path.blk[state->path.active - 1];
1859                ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1860                leaf = blk->bp->b_addr;
1861                lep = &leaf->ents[blk->index];
1862                ASSERT(state->extravalid);
1863                /*
1864                 * Point to the data entry.
1865                 */
1866                hdr = state->extrablk.bp->b_addr;
1867                ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
1868                dep = (xfs_dir2_data_entry_t *)
1869                      ((char *)hdr +
1870                       xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
1871                ASSERT(inum != be64_to_cpu(dep->inumber));
1872                /*
1873                 * Fill in the new inode number and log the entry.
1874                 */
1875                dep->inumber = cpu_to_be64(inum);
1876                xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
1877                rval = 0;
1878        }
1879        /*
1880         * Didn't find it, and we're holding a data block.  Drop it.
1881         */
1882        else if (state->extravalid) {
1883                xfs_trans_brelse(args->trans, state->extrablk.bp);
1884                state->extrablk.bp = NULL;
1885        }
1886        /*
1887         * Release all the buffers in the cursor.
1888         */
1889        for (i = 0; i < state->path.active; i++) {
1890                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
1891                state->path.blk[i].bp = NULL;
1892        }
1893        xfs_da_state_free(state);
1894        return rval;
1895}
1896
1897/*
1898 * Trim off a trailing empty freespace block.
1899 * Return (in rvalp) 1 if we did it, 0 if not.
1900 */
1901int                                             /* error */
1902xfs_dir2_node_trim_free(
1903        xfs_da_args_t           *args,          /* operation arguments */
1904        xfs_fileoff_t           fo,             /* free block number */
1905        int                     *rvalp)         /* out: did something */
1906{
1907        struct xfs_buf          *bp;            /* freespace buffer */
1908        xfs_inode_t             *dp;            /* incore directory inode */
1909        int                     error;          /* error return code */
1910        xfs_dir2_free_t         *free;          /* freespace structure */
1911        xfs_mount_t             *mp;            /* filesystem mount point */
1912        xfs_trans_t             *tp;            /* transaction pointer */
1913
1914        dp = args->dp;
1915        mp = dp->i_mount;
1916        tp = args->trans;
1917        /*
1918         * Read the freespace block.
1919         */
1920        if (unlikely(error = xfs_da_read_buf(tp, dp, (xfs_dablk_t)fo, -2, &bp,
1921                        XFS_DATA_FORK))) {
1922                return error;
1923        }
1924
1925        /*
1926         * There can be holes in freespace.  If fo is a hole, there's
1927         * nothing to do.
1928         */
1929        if (bp == NULL) {
1930                return 0;
1931        }
1932        free = bp->b_addr;
1933        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1934        /*
1935         * If there are used entries, there's nothing to do.
1936         */
1937        if (be32_to_cpu(free->hdr.nused) > 0) {
1938                xfs_trans_brelse(tp, bp);
1939                *rvalp = 0;
1940                return 0;
1941        }
1942        /*
1943         * Blow the block away.
1944         */
1945        if ((error =
1946            xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
1947                    bp))) {
1948                /*
1949                 * Can't fail with ENOSPC since that only happens with no
1950                 * space reservation, when breaking up an extent into two
1951                 * pieces.  This is the last block of an extent.
1952                 */
1953                ASSERT(error != ENOSPC);
1954                xfs_trans_brelse(tp, bp);
1955                return error;
1956        }
1957        /*
1958         * Return that we succeeded.
1959         */
1960        *rvalp = 1;
1961        return 0;
1962}
1963
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