linux/fs/xfs/xfs_dir2_node.c
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   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_priv.h"
  34#include "xfs_error.h"
  35#include "xfs_trace.h"
  36#include "xfs_buf_item.h"
  37#include "xfs_cksum.h"
  38
  39/*
  40 * Function declarations.
  41 */
  42static int xfs_dir2_leafn_add(struct xfs_buf *bp, xfs_da_args_t *args,
  43                              int index);
  44static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  45                                     xfs_da_state_blk_t *blk1,
  46                                     xfs_da_state_blk_t *blk2);
  47static int xfs_dir2_leafn_remove(xfs_da_args_t *args, struct xfs_buf *bp,
  48                                 int index, xfs_da_state_blk_t *dblk,
  49                                 int *rval);
  50static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  51                                     xfs_da_state_blk_t *fblk);
  52
  53/*
  54 * Check internal consistency of a leafn block.
  55 */
  56#ifdef DEBUG
  57#define xfs_dir3_leaf_check(mp, bp) \
  58do { \
  59        if (!xfs_dir3_leafn_check((mp), (bp))) \
  60                ASSERT(0); \
  61} while (0);
  62
  63static bool
  64xfs_dir3_leafn_check(
  65        struct xfs_mount        *mp,
  66        struct xfs_buf          *bp)
  67{
  68        struct xfs_dir2_leaf    *leaf = bp->b_addr;
  69        struct xfs_dir3_icleaf_hdr leafhdr;
  70
  71        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
  72
  73        if (leafhdr.magic == XFS_DIR3_LEAFN_MAGIC) {
  74                struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
  75                if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
  76                        return false;
  77        } else if (leafhdr.magic != XFS_DIR2_LEAFN_MAGIC)
  78                return false;
  79
  80        return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
  81}
  82#else
  83#define xfs_dir3_leaf_check(mp, bp)
  84#endif
  85
  86static bool
  87xfs_dir3_free_verify(
  88        struct xfs_buf          *bp)
  89{
  90        struct xfs_mount        *mp = bp->b_target->bt_mount;
  91        struct xfs_dir2_free_hdr *hdr = bp->b_addr;
  92
  93        if (xfs_sb_version_hascrc(&mp->m_sb)) {
  94                struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  95
  96                if (hdr3->magic != cpu_to_be32(XFS_DIR3_FREE_MAGIC))
  97                        return false;
  98                if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_uuid))
  99                        return false;
 100                if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
 101                        return false;
 102        } else {
 103                if (hdr->magic != cpu_to_be32(XFS_DIR2_FREE_MAGIC))
 104                        return false;
 105        }
 106
 107        /* XXX: should bounds check the xfs_dir3_icfree_hdr here */
 108
 109        return true;
 110}
 111
 112static void
 113xfs_dir3_free_read_verify(
 114        struct xfs_buf  *bp)
 115{
 116        struct xfs_mount        *mp = bp->b_target->bt_mount;
 117
 118        if ((xfs_sb_version_hascrc(&mp->m_sb) &&
 119             !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
 120                                          XFS_DIR3_FREE_CRC_OFF)) ||
 121            !xfs_dir3_free_verify(bp)) {
 122                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 123                xfs_buf_ioerror(bp, EFSCORRUPTED);
 124        }
 125}
 126
 127static void
 128xfs_dir3_free_write_verify(
 129        struct xfs_buf  *bp)
 130{
 131        struct xfs_mount        *mp = bp->b_target->bt_mount;
 132        struct xfs_buf_log_item *bip = bp->b_fspriv;
 133        struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 134
 135        if (!xfs_dir3_free_verify(bp)) {
 136                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 137                xfs_buf_ioerror(bp, EFSCORRUPTED);
 138                return;
 139        }
 140
 141        if (!xfs_sb_version_hascrc(&mp->m_sb))
 142                return;
 143
 144        if (bip)
 145                hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
 146
 147        xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_FREE_CRC_OFF);
 148}
 149
 150const struct xfs_buf_ops xfs_dir3_free_buf_ops = {
 151        .verify_read = xfs_dir3_free_read_verify,
 152        .verify_write = xfs_dir3_free_write_verify,
 153};
 154
 155
 156static int
 157__xfs_dir3_free_read(
 158        struct xfs_trans        *tp,
 159        struct xfs_inode        *dp,
 160        xfs_dablk_t             fbno,
 161        xfs_daddr_t             mappedbno,
 162        struct xfs_buf          **bpp)
 163{
 164        int                     err;
 165
 166        err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 167                                XFS_DATA_FORK, &xfs_dir3_free_buf_ops);
 168
 169        /* try read returns without an error or *bpp if it lands in a hole */
 170        if (!err && tp && *bpp)
 171                xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF);
 172        return err;
 173}
 174
 175int
 176xfs_dir2_free_read(
 177        struct xfs_trans        *tp,
 178        struct xfs_inode        *dp,
 179        xfs_dablk_t             fbno,
 180        struct xfs_buf          **bpp)
 181{
 182        return __xfs_dir3_free_read(tp, dp, fbno, -1, bpp);
 183}
 184
 185static int
 186xfs_dir2_free_try_read(
 187        struct xfs_trans        *tp,
 188        struct xfs_inode        *dp,
 189        xfs_dablk_t             fbno,
 190        struct xfs_buf          **bpp)
 191{
 192        return __xfs_dir3_free_read(tp, dp, fbno, -2, bpp);
 193}
 194
 195
 196void
 197xfs_dir3_free_hdr_from_disk(
 198        struct xfs_dir3_icfree_hdr      *to,
 199        struct xfs_dir2_free            *from)
 200{
 201        if (from->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC)) {
 202                to->magic = be32_to_cpu(from->hdr.magic);
 203                to->firstdb = be32_to_cpu(from->hdr.firstdb);
 204                to->nvalid = be32_to_cpu(from->hdr.nvalid);
 205                to->nused = be32_to_cpu(from->hdr.nused);
 206        } else {
 207                struct xfs_dir3_free_hdr *hdr3 = (struct xfs_dir3_free_hdr *)from;
 208
 209                to->magic = be32_to_cpu(hdr3->hdr.magic);
 210                to->firstdb = be32_to_cpu(hdr3->firstdb);
 211                to->nvalid = be32_to_cpu(hdr3->nvalid);
 212                to->nused = be32_to_cpu(hdr3->nused);
 213        }
 214
 215        ASSERT(to->magic == XFS_DIR2_FREE_MAGIC ||
 216               to->magic == XFS_DIR3_FREE_MAGIC);
 217}
 218
 219static void
 220xfs_dir3_free_hdr_to_disk(
 221        struct xfs_dir2_free            *to,
 222        struct xfs_dir3_icfree_hdr      *from)
 223{
 224        ASSERT(from->magic == XFS_DIR2_FREE_MAGIC ||
 225               from->magic == XFS_DIR3_FREE_MAGIC);
 226
 227        if (from->magic == XFS_DIR2_FREE_MAGIC) {
 228                to->hdr.magic = cpu_to_be32(from->magic);
 229                to->hdr.firstdb = cpu_to_be32(from->firstdb);
 230                to->hdr.nvalid = cpu_to_be32(from->nvalid);
 231                to->hdr.nused = cpu_to_be32(from->nused);
 232        } else {
 233                struct xfs_dir3_free_hdr *hdr3 = (struct xfs_dir3_free_hdr *)to;
 234
 235                hdr3->hdr.magic = cpu_to_be32(from->magic);
 236                hdr3->firstdb = cpu_to_be32(from->firstdb);
 237                hdr3->nvalid = cpu_to_be32(from->nvalid);
 238                hdr3->nused = cpu_to_be32(from->nused);
 239        }
 240}
 241
 242static int
 243xfs_dir3_free_get_buf(
 244        struct xfs_trans        *tp,
 245        struct xfs_inode        *dp,
 246        xfs_dir2_db_t           fbno,
 247        struct xfs_buf          **bpp)
 248{
 249        struct xfs_mount        *mp = dp->i_mount;
 250        struct xfs_buf          *bp;
 251        int                     error;
 252        struct xfs_dir3_icfree_hdr hdr;
 253
 254        error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, fbno),
 255                                   -1, &bp, XFS_DATA_FORK);
 256        if (error)
 257                return error;
 258
 259        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_FREE_BUF);
 260        bp->b_ops = &xfs_dir3_free_buf_ops;
 261
 262        /*
 263         * Initialize the new block to be empty, and remember
 264         * its first slot as our empty slot.
 265         */
 266        memset(bp->b_addr, 0, sizeof(struct xfs_dir3_free_hdr));
 267        memset(&hdr, 0, sizeof(hdr));
 268
 269        if (xfs_sb_version_hascrc(&mp->m_sb)) {
 270                struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 271
 272                hdr.magic = XFS_DIR3_FREE_MAGIC;
 273
 274                hdr3->hdr.blkno = cpu_to_be64(bp->b_bn);
 275                hdr3->hdr.owner = cpu_to_be64(dp->i_ino);
 276                uuid_copy(&hdr3->hdr.uuid, &mp->m_sb.sb_uuid);
 277        } else
 278                hdr.magic = XFS_DIR2_FREE_MAGIC;
 279        xfs_dir3_free_hdr_to_disk(bp->b_addr, &hdr);
 280        *bpp = bp;
 281        return 0;
 282}
 283
 284/*
 285 * Log entries from a freespace block.
 286 */
 287STATIC void
 288xfs_dir2_free_log_bests(
 289        struct xfs_trans        *tp,
 290        struct xfs_buf          *bp,
 291        int                     first,          /* first entry to log */
 292        int                     last)           /* last entry to log */
 293{
 294        xfs_dir2_free_t         *free;          /* freespace structure */
 295        __be16                  *bests;
 296
 297        free = bp->b_addr;
 298        bests = xfs_dir3_free_bests_p(tp->t_mountp, free);
 299        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 300               free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 301        xfs_trans_log_buf(tp, bp,
 302                (uint)((char *)&bests[first] - (char *)free),
 303                (uint)((char *)&bests[last] - (char *)free +
 304                       sizeof(bests[0]) - 1));
 305}
 306
 307/*
 308 * Log header from a freespace block.
 309 */
 310static void
 311xfs_dir2_free_log_header(
 312        struct xfs_trans        *tp,
 313        struct xfs_buf          *bp)
 314{
 315        xfs_dir2_free_t         *free;          /* freespace structure */
 316
 317        free = bp->b_addr;
 318        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 319               free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 320        xfs_trans_log_buf(tp, bp, 0, xfs_dir3_free_hdr_size(tp->t_mountp) - 1);
 321}
 322
 323/*
 324 * Convert a leaf-format directory to a node-format directory.
 325 * We need to change the magic number of the leaf block, and copy
 326 * the freespace table out of the leaf block into its own block.
 327 */
 328int                                             /* error */
 329xfs_dir2_leaf_to_node(
 330        xfs_da_args_t           *args,          /* operation arguments */
 331        struct xfs_buf          *lbp)           /* leaf buffer */
 332{
 333        xfs_inode_t             *dp;            /* incore directory inode */
 334        int                     error;          /* error return value */
 335        struct xfs_buf          *fbp;           /* freespace buffer */
 336        xfs_dir2_db_t           fdb;            /* freespace block number */
 337        xfs_dir2_free_t         *free;          /* freespace structure */
 338        __be16                  *from;          /* pointer to freespace entry */
 339        int                     i;              /* leaf freespace index */
 340        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 341        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 342        xfs_mount_t             *mp;            /* filesystem mount point */
 343        int                     n;              /* count of live freespc ents */
 344        xfs_dir2_data_off_t     off;            /* freespace entry value */
 345        __be16                  *to;            /* pointer to freespace entry */
 346        xfs_trans_t             *tp;            /* transaction pointer */
 347        struct xfs_dir3_icfree_hdr freehdr;
 348
 349        trace_xfs_dir2_leaf_to_node(args);
 350
 351        dp = args->dp;
 352        mp = dp->i_mount;
 353        tp = args->trans;
 354        /*
 355         * Add a freespace block to the directory.
 356         */
 357        if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 358                return error;
 359        }
 360        ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
 361        /*
 362         * Get the buffer for the new freespace block.
 363         */
 364        error = xfs_dir3_free_get_buf(tp, dp, fdb, &fbp);
 365        if (error)
 366                return error;
 367
 368        free = fbp->b_addr;
 369        xfs_dir3_free_hdr_from_disk(&freehdr, free);
 370        leaf = lbp->b_addr;
 371        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 372        ASSERT(be32_to_cpu(ltp->bestcount) <=
 373                                (uint)dp->i_d.di_size / mp->m_dirblksize);
 374
 375        /*
 376         * Copy freespace entries from the leaf block to the new block.
 377         * Count active entries.
 378         */
 379        from = xfs_dir2_leaf_bests_p(ltp);
 380        to = xfs_dir3_free_bests_p(mp, free);
 381        for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 382                if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 383                        n++;
 384                *to = cpu_to_be16(off);
 385        }
 386
 387        /*
 388         * Now initialize the freespace block header.
 389         */
 390        freehdr.nused = n;
 391        freehdr.nvalid = be32_to_cpu(ltp->bestcount);
 392
 393        xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
 394        xfs_dir2_free_log_bests(tp, fbp, 0, freehdr.nvalid - 1);
 395        xfs_dir2_free_log_header(tp, fbp);
 396
 397        /*
 398         * Converting the leaf to a leafnode is just a matter of changing the
 399         * magic number and the ops. Do the change directly to the buffer as
 400         * it's less work (and less code) than decoding the header to host
 401         * format and back again.
 402         */
 403        if (leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC))
 404                leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 405        else
 406                leaf->hdr.info.magic = cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 407        lbp->b_ops = &xfs_dir3_leafn_buf_ops;
 408        xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAFN_BUF);
 409        xfs_dir3_leaf_log_header(tp, lbp);
 410        xfs_dir3_leaf_check(mp, lbp);
 411        return 0;
 412}
 413
 414/*
 415 * Add a leaf entry to a leaf block in a node-form directory.
 416 * The other work necessary is done from the caller.
 417 */
 418static int                                      /* error */
 419xfs_dir2_leafn_add(
 420        struct xfs_buf          *bp,            /* leaf buffer */
 421        xfs_da_args_t           *args,          /* operation arguments */
 422        int                     index)          /* insertion pt for new entry */
 423{
 424        int                     compact;        /* compacting stale leaves */
 425        xfs_inode_t             *dp;            /* incore directory inode */
 426        int                     highstale;      /* next stale entry */
 427        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 428        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 429        int                     lfloghigh;      /* high leaf entry logging */
 430        int                     lfloglow;       /* low leaf entry logging */
 431        int                     lowstale;       /* previous stale entry */
 432        xfs_mount_t             *mp;            /* filesystem mount point */
 433        xfs_trans_t             *tp;            /* transaction pointer */
 434        struct xfs_dir3_icleaf_hdr leafhdr;
 435        struct xfs_dir2_leaf_entry *ents;
 436
 437        trace_xfs_dir2_leafn_add(args, index);
 438
 439        dp = args->dp;
 440        mp = dp->i_mount;
 441        tp = args->trans;
 442        leaf = bp->b_addr;
 443        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 444        ents = xfs_dir3_leaf_ents_p(leaf);
 445
 446        /*
 447         * Quick check just to make sure we are not going to index
 448         * into other peoples memory
 449         */
 450        if (index < 0)
 451                return XFS_ERROR(EFSCORRUPTED);
 452
 453        /*
 454         * If there are already the maximum number of leaf entries in
 455         * the block, if there are no stale entries it won't fit.
 456         * Caller will do a split.  If there are stale entries we'll do
 457         * a compact.
 458         */
 459
 460        if (leafhdr.count == xfs_dir3_max_leaf_ents(mp, leaf)) {
 461                if (!leafhdr.stale)
 462                        return XFS_ERROR(ENOSPC);
 463                compact = leafhdr.stale > 1;
 464        } else
 465                compact = 0;
 466        ASSERT(index == 0 || be32_to_cpu(ents[index - 1].hashval) <= args->hashval);
 467        ASSERT(index == leafhdr.count ||
 468               be32_to_cpu(ents[index].hashval) >= args->hashval);
 469
 470        if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 471                return 0;
 472
 473        /*
 474         * Compact out all but one stale leaf entry.  Leaves behind
 475         * the entry closest to index.
 476         */
 477        if (compact)
 478                xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 479                                         &highstale, &lfloglow, &lfloghigh);
 480        else if (leafhdr.stale) {
 481                /*
 482                 * Set impossible logging indices for this case.
 483                 */
 484                lfloglow = leafhdr.count;
 485                lfloghigh = -1;
 486        }
 487
 488        /*
 489         * Insert the new entry, log everything.
 490         */
 491        lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 492                                       highstale, &lfloglow, &lfloghigh);
 493
 494        lep->hashval = cpu_to_be32(args->hashval);
 495        lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
 496                                args->blkno, args->index));
 497
 498        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
 499        xfs_dir3_leaf_log_header(tp, bp);
 500        xfs_dir3_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
 501        xfs_dir3_leaf_check(mp, bp);
 502        return 0;
 503}
 504
 505#ifdef DEBUG
 506static void
 507xfs_dir2_free_hdr_check(
 508        struct xfs_mount *mp,
 509        struct xfs_buf  *bp,
 510        xfs_dir2_db_t   db)
 511{
 512        struct xfs_dir3_icfree_hdr hdr;
 513
 514        xfs_dir3_free_hdr_from_disk(&hdr, bp->b_addr);
 515
 516        ASSERT((hdr.firstdb % xfs_dir3_free_max_bests(mp)) == 0);
 517        ASSERT(hdr.firstdb <= db);
 518        ASSERT(db < hdr.firstdb + hdr.nvalid);
 519}
 520#else
 521#define xfs_dir2_free_hdr_check(mp, dp, db)
 522#endif  /* DEBUG */
 523
 524/*
 525 * Return the last hash value in the leaf.
 526 * Stale entries are ok.
 527 */
 528xfs_dahash_t                                    /* hash value */
 529xfs_dir2_leafn_lasthash(
 530        struct xfs_buf  *bp,                    /* leaf buffer */
 531        int             *count)                 /* count of entries in leaf */
 532{
 533        struct xfs_dir2_leaf    *leaf = bp->b_addr;
 534        struct xfs_dir2_leaf_entry *ents;
 535        struct xfs_dir3_icleaf_hdr leafhdr;
 536
 537        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 538
 539        ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
 540               leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
 541
 542        if (count)
 543                *count = leafhdr.count;
 544        if (!leafhdr.count)
 545                return 0;
 546
 547        ents = xfs_dir3_leaf_ents_p(leaf);
 548        return be32_to_cpu(ents[leafhdr.count - 1].hashval);
 549}
 550
 551/*
 552 * Look up a leaf entry for space to add a name in a node-format leaf block.
 553 * The extrablk in state is a freespace block.
 554 */
 555STATIC int
 556xfs_dir2_leafn_lookup_for_addname(
 557        struct xfs_buf          *bp,            /* leaf buffer */
 558        xfs_da_args_t           *args,          /* operation arguments */
 559        int                     *indexp,        /* out: leaf entry index */
 560        xfs_da_state_t          *state)         /* state to fill in */
 561{
 562        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 563        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 564        xfs_dir2_db_t           curfdb = -1;    /* current free block number */
 565        xfs_inode_t             *dp;            /* incore directory inode */
 566        int                     error;          /* error return value */
 567        int                     fi;             /* free entry index */
 568        xfs_dir2_free_t         *free = NULL;   /* free block structure */
 569        int                     index;          /* leaf entry index */
 570        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 571        int                     length;         /* length of new data entry */
 572        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 573        xfs_mount_t             *mp;            /* filesystem mount point */
 574        xfs_dir2_db_t           newdb;          /* new data block number */
 575        xfs_dir2_db_t           newfdb;         /* new free block number */
 576        xfs_trans_t             *tp;            /* transaction pointer */
 577        struct xfs_dir2_leaf_entry *ents;
 578        struct xfs_dir3_icleaf_hdr leafhdr;
 579
 580        dp = args->dp;
 581        tp = args->trans;
 582        mp = dp->i_mount;
 583        leaf = bp->b_addr;
 584        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 585        ents = xfs_dir3_leaf_ents_p(leaf);
 586
 587        xfs_dir3_leaf_check(mp, bp);
 588        ASSERT(leafhdr.count > 0);
 589
 590        /*
 591         * Look up the hash value in the leaf entries.
 592         */
 593        index = xfs_dir2_leaf_search_hash(args, bp);
 594        /*
 595         * Do we have a buffer coming in?
 596         */
 597        if (state->extravalid) {
 598                /* If so, it's a free block buffer, get the block number. */
 599                curbp = state->extrablk.bp;
 600                curfdb = state->extrablk.blkno;
 601                free = curbp->b_addr;
 602                ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 603                       free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 604        }
 605        length = xfs_dir2_data_entsize(args->namelen);
 606        /*
 607         * Loop over leaf entries with the right hash value.
 608         */
 609        for (lep = &ents[index];
 610             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 611             lep++, index++) {
 612                /*
 613                 * Skip stale leaf entries.
 614                 */
 615                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 616                        continue;
 617                /*
 618                 * Pull the data block number from the entry.
 619                 */
 620                newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 621                /*
 622                 * For addname, we're looking for a place to put the new entry.
 623                 * We want to use a data block with an entry of equal
 624                 * hash value to ours if there is one with room.
 625                 *
 626                 * If this block isn't the data block we already have
 627                 * in hand, take a look at it.
 628                 */
 629                if (newdb != curdb) {
 630                        __be16 *bests;
 631
 632                        curdb = newdb;
 633                        /*
 634                         * Convert the data block to the free block
 635                         * holding its freespace information.
 636                         */
 637                        newfdb = xfs_dir2_db_to_fdb(mp, newdb);
 638                        /*
 639                         * If it's not the one we have in hand, read it in.
 640                         */
 641                        if (newfdb != curfdb) {
 642                                /*
 643                                 * If we had one before, drop it.
 644                                 */
 645                                if (curbp)
 646                                        xfs_trans_brelse(tp, curbp);
 647
 648                                error = xfs_dir2_free_read(tp, dp,
 649                                                xfs_dir2_db_to_da(mp, newfdb),
 650                                                &curbp);
 651                                if (error)
 652                                        return error;
 653                                free = curbp->b_addr;
 654
 655                                xfs_dir2_free_hdr_check(mp, curbp, curdb);
 656                        }
 657                        /*
 658                         * Get the index for our entry.
 659                         */
 660                        fi = xfs_dir2_db_to_fdindex(mp, curdb);
 661                        /*
 662                         * If it has room, return it.
 663                         */
 664                        bests = xfs_dir3_free_bests_p(mp, free);
 665                        if (unlikely(bests[fi] == cpu_to_be16(NULLDATAOFF))) {
 666                                XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 667                                                        XFS_ERRLEVEL_LOW, mp);
 668                                if (curfdb != newfdb)
 669                                        xfs_trans_brelse(tp, curbp);
 670                                return XFS_ERROR(EFSCORRUPTED);
 671                        }
 672                        curfdb = newfdb;
 673                        if (be16_to_cpu(bests[fi]) >= length)
 674                                goto out;
 675                }
 676        }
 677        /* Didn't find any space */
 678        fi = -1;
 679out:
 680        ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 681        if (curbp) {
 682                /* Giving back a free block. */
 683                state->extravalid = 1;
 684                state->extrablk.bp = curbp;
 685                state->extrablk.index = fi;
 686                state->extrablk.blkno = curfdb;
 687
 688                /*
 689                 * Important: this magic number is not in the buffer - it's for
 690                 * buffer type information and therefore only the free/data type
 691                 * matters here, not whether CRCs are enabled or not.
 692                 */
 693                state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 694        } else {
 695                state->extravalid = 0;
 696        }
 697        /*
 698         * Return the index, that will be the insertion point.
 699         */
 700        *indexp = index;
 701        return XFS_ERROR(ENOENT);
 702}
 703
 704/*
 705 * Look up a leaf entry in a node-format leaf block.
 706 * The extrablk in state a data block.
 707 */
 708STATIC int
 709xfs_dir2_leafn_lookup_for_entry(
 710        struct xfs_buf          *bp,            /* leaf buffer */
 711        xfs_da_args_t           *args,          /* operation arguments */
 712        int                     *indexp,        /* out: leaf entry index */
 713        xfs_da_state_t          *state)         /* state to fill in */
 714{
 715        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 716        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 717        xfs_dir2_data_entry_t   *dep;           /* data block entry */
 718        xfs_inode_t             *dp;            /* incore directory inode */
 719        int                     error;          /* error return value */
 720        int                     index;          /* leaf entry index */
 721        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 722        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 723        xfs_mount_t             *mp;            /* filesystem mount point */
 724        xfs_dir2_db_t           newdb;          /* new data block number */
 725        xfs_trans_t             *tp;            /* transaction pointer */
 726        enum xfs_dacmp          cmp;            /* comparison result */
 727        struct xfs_dir2_leaf_entry *ents;
 728        struct xfs_dir3_icleaf_hdr leafhdr;
 729
 730        dp = args->dp;
 731        tp = args->trans;
 732        mp = dp->i_mount;
 733        leaf = bp->b_addr;
 734        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 735        ents = xfs_dir3_leaf_ents_p(leaf);
 736
 737        xfs_dir3_leaf_check(mp, bp);
 738        ASSERT(leafhdr.count > 0);
 739
 740        /*
 741         * Look up the hash value in the leaf entries.
 742         */
 743        index = xfs_dir2_leaf_search_hash(args, bp);
 744        /*
 745         * Do we have a buffer coming in?
 746         */
 747        if (state->extravalid) {
 748                curbp = state->extrablk.bp;
 749                curdb = state->extrablk.blkno;
 750        }
 751        /*
 752         * Loop over leaf entries with the right hash value.
 753         */
 754        for (lep = &ents[index];
 755             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 756             lep++, index++) {
 757                /*
 758                 * Skip stale leaf entries.
 759                 */
 760                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 761                        continue;
 762                /*
 763                 * Pull the data block number from the entry.
 764                 */
 765                newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 766                /*
 767                 * Not adding a new entry, so we really want to find
 768                 * the name given to us.
 769                 *
 770                 * If it's a different data block, go get it.
 771                 */
 772                if (newdb != curdb) {
 773                        /*
 774                         * If we had a block before that we aren't saving
 775                         * for a CI name, drop it
 776                         */
 777                        if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 778                                                curdb != state->extrablk.blkno))
 779                                xfs_trans_brelse(tp, curbp);
 780                        /*
 781                         * If needing the block that is saved with a CI match,
 782                         * use it otherwise read in the new data block.
 783                         */
 784                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 785                                        newdb == state->extrablk.blkno) {
 786                                ASSERT(state->extravalid);
 787                                curbp = state->extrablk.bp;
 788                        } else {
 789                                error = xfs_dir3_data_read(tp, dp,
 790                                                xfs_dir2_db_to_da(mp, newdb),
 791                                                -1, &curbp);
 792                                if (error)
 793                                        return error;
 794                        }
 795                        xfs_dir3_data_check(dp, curbp);
 796                        curdb = newdb;
 797                }
 798                /*
 799                 * Point to the data entry.
 800                 */
 801                dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr +
 802                        xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
 803                /*
 804                 * Compare the entry and if it's an exact match, return
 805                 * EEXIST immediately. If it's the first case-insensitive
 806                 * match, store the block & inode number and continue looking.
 807                 */
 808                cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 809                if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 810                        /* If there is a CI match block, drop it */
 811                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 812                                                curdb != state->extrablk.blkno)
 813                                xfs_trans_brelse(tp, state->extrablk.bp);
 814                        args->cmpresult = cmp;
 815                        args->inumber = be64_to_cpu(dep->inumber);
 816                        *indexp = index;
 817                        state->extravalid = 1;
 818                        state->extrablk.bp = curbp;
 819                        state->extrablk.blkno = curdb;
 820                        state->extrablk.index = (int)((char *)dep -
 821                                                        (char *)curbp->b_addr);
 822                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 823                        curbp->b_ops = &xfs_dir3_data_buf_ops;
 824                        xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 825                        if (cmp == XFS_CMP_EXACT)
 826                                return XFS_ERROR(EEXIST);
 827                }
 828        }
 829        ASSERT(index == leafhdr.count || (args->op_flags & XFS_DA_OP_OKNOENT));
 830        if (curbp) {
 831                if (args->cmpresult == XFS_CMP_DIFFERENT) {
 832                        /* Giving back last used data block. */
 833                        state->extravalid = 1;
 834                        state->extrablk.bp = curbp;
 835                        state->extrablk.index = -1;
 836                        state->extrablk.blkno = curdb;
 837                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 838                        curbp->b_ops = &xfs_dir3_data_buf_ops;
 839                        xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 840                } else {
 841                        /* If the curbp is not the CI match block, drop it */
 842                        if (state->extrablk.bp != curbp)
 843                                xfs_trans_brelse(tp, curbp);
 844                }
 845        } else {
 846                state->extravalid = 0;
 847        }
 848        *indexp = index;
 849        return XFS_ERROR(ENOENT);
 850}
 851
 852/*
 853 * Look up a leaf entry in a node-format leaf block.
 854 * If this is an addname then the extrablk in state is a freespace block,
 855 * otherwise it's a data block.
 856 */
 857int
 858xfs_dir2_leafn_lookup_int(
 859        struct xfs_buf          *bp,            /* leaf buffer */
 860        xfs_da_args_t           *args,          /* operation arguments */
 861        int                     *indexp,        /* out: leaf entry index */
 862        xfs_da_state_t          *state)         /* state to fill in */
 863{
 864        if (args->op_flags & XFS_DA_OP_ADDNAME)
 865                return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 866                                                        state);
 867        return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 868}
 869
 870/*
 871 * Move count leaf entries from source to destination leaf.
 872 * Log entries and headers.  Stale entries are preserved.
 873 */
 874static void
 875xfs_dir3_leafn_moveents(
 876        xfs_da_args_t                   *args,  /* operation arguments */
 877        struct xfs_buf                  *bp_s,  /* source */
 878        struct xfs_dir3_icleaf_hdr      *shdr,
 879        struct xfs_dir2_leaf_entry      *sents,
 880        int                             start_s,/* source leaf index */
 881        struct xfs_buf                  *bp_d,  /* destination */
 882        struct xfs_dir3_icleaf_hdr      *dhdr,
 883        struct xfs_dir2_leaf_entry      *dents,
 884        int                             start_d,/* destination leaf index */
 885        int                             count)  /* count of leaves to copy */
 886{
 887        struct xfs_trans                *tp = args->trans;
 888        int                             stale;  /* count stale leaves copied */
 889
 890        trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 891
 892        /*
 893         * Silently return if nothing to do.
 894         */
 895        if (count == 0)
 896                return;
 897
 898        /*
 899         * If the destination index is not the end of the current
 900         * destination leaf entries, open up a hole in the destination
 901         * to hold the new entries.
 902         */
 903        if (start_d < dhdr->count) {
 904                memmove(&dents[start_d + count], &dents[start_d],
 905                        (dhdr->count - start_d) * sizeof(xfs_dir2_leaf_entry_t));
 906                xfs_dir3_leaf_log_ents(tp, bp_d, start_d + count,
 907                                       count + dhdr->count - 1);
 908        }
 909        /*
 910         * If the source has stale leaves, count the ones in the copy range
 911         * so we can update the header correctly.
 912         */
 913        if (shdr->stale) {
 914                int     i;                      /* temp leaf index */
 915
 916                for (i = start_s, stale = 0; i < start_s + count; i++) {
 917                        if (sents[i].address ==
 918                                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 919                                stale++;
 920                }
 921        } else
 922                stale = 0;
 923        /*
 924         * Copy the leaf entries from source to destination.
 925         */
 926        memcpy(&dents[start_d], &sents[start_s],
 927                count * sizeof(xfs_dir2_leaf_entry_t));
 928        xfs_dir3_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
 929
 930        /*
 931         * If there are source entries after the ones we copied,
 932         * delete the ones we copied by sliding the next ones down.
 933         */
 934        if (start_s + count < shdr->count) {
 935                memmove(&sents[start_s], &sents[start_s + count],
 936                        count * sizeof(xfs_dir2_leaf_entry_t));
 937                xfs_dir3_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
 938        }
 939
 940        /*
 941         * Update the headers and log them.
 942         */
 943        shdr->count -= count;
 944        shdr->stale -= stale;
 945        dhdr->count += count;
 946        dhdr->stale += stale;
 947}
 948
 949/*
 950 * Determine the sort order of two leaf blocks.
 951 * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 952 */
 953int                                             /* sort order */
 954xfs_dir2_leafn_order(
 955        struct xfs_buf          *leaf1_bp,              /* leaf1 buffer */
 956        struct xfs_buf          *leaf2_bp)              /* leaf2 buffer */
 957{
 958        struct xfs_dir2_leaf    *leaf1 = leaf1_bp->b_addr;
 959        struct xfs_dir2_leaf    *leaf2 = leaf2_bp->b_addr;
 960        struct xfs_dir2_leaf_entry *ents1;
 961        struct xfs_dir2_leaf_entry *ents2;
 962        struct xfs_dir3_icleaf_hdr hdr1;
 963        struct xfs_dir3_icleaf_hdr hdr2;
 964
 965        xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
 966        xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
 967        ents1 = xfs_dir3_leaf_ents_p(leaf1);
 968        ents2 = xfs_dir3_leaf_ents_p(leaf2);
 969
 970        if (hdr1.count > 0 && hdr2.count > 0 &&
 971            (be32_to_cpu(ents2[0].hashval) < be32_to_cpu(ents1[0].hashval) ||
 972             be32_to_cpu(ents2[hdr2.count - 1].hashval) <
 973                                be32_to_cpu(ents1[hdr1.count - 1].hashval)))
 974                return 1;
 975        return 0;
 976}
 977
 978/*
 979 * Rebalance leaf entries between two leaf blocks.
 980 * This is actually only called when the second block is new,
 981 * though the code deals with the general case.
 982 * A new entry will be inserted in one of the blocks, and that
 983 * entry is taken into account when balancing.
 984 */
 985static void
 986xfs_dir2_leafn_rebalance(
 987        xfs_da_state_t          *state,         /* btree cursor */
 988        xfs_da_state_blk_t      *blk1,          /* first btree block */
 989        xfs_da_state_blk_t      *blk2)          /* second btree block */
 990{
 991        xfs_da_args_t           *args;          /* operation arguments */
 992        int                     count;          /* count (& direction) leaves */
 993        int                     isleft;         /* new goes in left leaf */
 994        xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
 995        xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
 996        int                     mid;            /* midpoint leaf index */
 997#if defined(DEBUG) || defined(XFS_WARN)
 998        int                     oldstale;       /* old count of stale leaves */
 999#endif
1000        int                     oldsum;         /* old total leaf count */
1001        int                     swap;           /* swapped leaf blocks */
1002        struct xfs_dir2_leaf_entry *ents1;
1003        struct xfs_dir2_leaf_entry *ents2;
1004        struct xfs_dir3_icleaf_hdr hdr1;
1005        struct xfs_dir3_icleaf_hdr hdr2;
1006
1007        args = state->args;
1008        /*
1009         * If the block order is wrong, swap the arguments.
1010         */
1011        if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
1012                xfs_da_state_blk_t      *tmp;   /* temp for block swap */
1013
1014                tmp = blk1;
1015                blk1 = blk2;
1016                blk2 = tmp;
1017        }
1018        leaf1 = blk1->bp->b_addr;
1019        leaf2 = blk2->bp->b_addr;
1020        xfs_dir3_leaf_hdr_from_disk(&hdr1, leaf1);
1021        xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf2);
1022        ents1 = xfs_dir3_leaf_ents_p(leaf1);
1023        ents2 = xfs_dir3_leaf_ents_p(leaf2);
1024
1025        oldsum = hdr1.count + hdr2.count;
1026#if defined(DEBUG) || defined(XFS_WARN)
1027        oldstale = hdr1.stale + hdr2.stale;
1028#endif
1029        mid = oldsum >> 1;
1030
1031        /*
1032         * If the old leaf count was odd then the new one will be even,
1033         * so we need to divide the new count evenly.
1034         */
1035        if (oldsum & 1) {
1036                xfs_dahash_t    midhash;        /* middle entry hash value */
1037
1038                if (mid >= hdr1.count)
1039                        midhash = be32_to_cpu(ents2[mid - hdr1.count].hashval);
1040                else
1041                        midhash = be32_to_cpu(ents1[mid].hashval);
1042                isleft = args->hashval <= midhash;
1043        }
1044        /*
1045         * If the old count is even then the new count is odd, so there's
1046         * no preferred side for the new entry.
1047         * Pick the left one.
1048         */
1049        else
1050                isleft = 1;
1051        /*
1052         * Calculate moved entry count.  Positive means left-to-right,
1053         * negative means right-to-left.  Then move the entries.
1054         */
1055        count = hdr1.count - mid + (isleft == 0);
1056        if (count > 0)
1057                xfs_dir3_leafn_moveents(args, blk1->bp, &hdr1, ents1,
1058                                        hdr1.count - count, blk2->bp,
1059                                        &hdr2, ents2, 0, count);
1060        else if (count < 0)
1061                xfs_dir3_leafn_moveents(args, blk2->bp, &hdr2, ents2, 0,
1062                                        blk1->bp, &hdr1, ents1,
1063                                        hdr1.count, count);
1064
1065        ASSERT(hdr1.count + hdr2.count == oldsum);
1066        ASSERT(hdr1.stale + hdr2.stale == oldstale);
1067
1068        /* log the changes made when moving the entries */
1069        xfs_dir3_leaf_hdr_to_disk(leaf1, &hdr1);
1070        xfs_dir3_leaf_hdr_to_disk(leaf2, &hdr2);
1071        xfs_dir3_leaf_log_header(args->trans, blk1->bp);
1072        xfs_dir3_leaf_log_header(args->trans, blk2->bp);
1073
1074        xfs_dir3_leaf_check(args->dp->i_mount, blk1->bp);
1075        xfs_dir3_leaf_check(args->dp->i_mount, blk2->bp);
1076
1077        /*
1078         * Mark whether we're inserting into the old or new leaf.
1079         */
1080        if (hdr1.count < hdr2.count)
1081                state->inleaf = swap;
1082        else if (hdr1.count > hdr2.count)
1083                state->inleaf = !swap;
1084        else
1085                state->inleaf = swap ^ (blk1->index <= hdr1.count);
1086        /*
1087         * Adjust the expected index for insertion.
1088         */
1089        if (!state->inleaf)
1090                blk2->index = blk1->index - hdr1.count;
1091
1092        /*
1093         * Finally sanity check just to make sure we are not returning a
1094         * negative index
1095         */
1096        if(blk2->index < 0) {
1097                state->inleaf = 1;
1098                blk2->index = 0;
1099                xfs_alert(args->dp->i_mount,
1100        "%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
1101                        __func__, blk1->index);
1102        }
1103}
1104
1105static int
1106xfs_dir3_data_block_free(
1107        xfs_da_args_t           *args,
1108        struct xfs_dir2_data_hdr *hdr,
1109        struct xfs_dir2_free    *free,
1110        xfs_dir2_db_t           fdb,
1111        int                     findex,
1112        struct xfs_buf          *fbp,
1113        int                     longest)
1114{
1115        struct xfs_trans        *tp = args->trans;
1116        int                     logfree = 0;
1117        __be16                  *bests;
1118        struct xfs_dir3_icfree_hdr freehdr;
1119
1120        xfs_dir3_free_hdr_from_disk(&freehdr, free);
1121
1122        bests = xfs_dir3_free_bests_p(tp->t_mountp, free);
1123        if (hdr) {
1124                /*
1125                 * Data block is not empty, just set the free entry to the new
1126                 * value.
1127                 */
1128                bests[findex] = cpu_to_be16(longest);
1129                xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1130                return 0;
1131        }
1132
1133        /* One less used entry in the free table. */
1134        freehdr.nused--;
1135
1136        /*
1137         * If this was the last entry in the table, we can trim the table size
1138         * back.  There might be other entries at the end referring to
1139         * non-existent data blocks, get those too.
1140         */
1141        if (findex == freehdr.nvalid - 1) {
1142                int     i;              /* free entry index */
1143
1144                for (i = findex - 1; i >= 0; i--) {
1145                        if (bests[i] != cpu_to_be16(NULLDATAOFF))
1146                                break;
1147                }
1148                freehdr.nvalid = i + 1;
1149                logfree = 0;
1150        } else {
1151                /* Not the last entry, just punch it out.  */
1152                bests[findex] = cpu_to_be16(NULLDATAOFF);
1153                logfree = 1;
1154        }
1155
1156        xfs_dir3_free_hdr_to_disk(free, &freehdr);
1157        xfs_dir2_free_log_header(tp, fbp);
1158
1159        /*
1160         * If there are no useful entries left in the block, get rid of the
1161         * block if we can.
1162         */
1163        if (!freehdr.nused) {
1164                int error;
1165
1166                error = xfs_dir2_shrink_inode(args, fdb, fbp);
1167                if (error == 0) {
1168                        fbp = NULL;
1169                        logfree = 0;
1170                } else if (error != ENOSPC || args->total != 0)
1171                        return error;
1172                /*
1173                 * It's possible to get ENOSPC if there is no
1174                 * space reservation.  In this case some one
1175                 * else will eventually get rid of this block.
1176                 */
1177        }
1178
1179        /* Log the free entry that changed, unless we got rid of it.  */
1180        if (logfree)
1181                xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1182        return 0;
1183}
1184
1185/*
1186 * Remove an entry from a node directory.
1187 * This removes the leaf entry and the data entry,
1188 * and updates the free block if necessary.
1189 */
1190static int                                      /* error */
1191xfs_dir2_leafn_remove(
1192        xfs_da_args_t           *args,          /* operation arguments */
1193        struct xfs_buf          *bp,            /* leaf buffer */
1194        int                     index,          /* leaf entry index */
1195        xfs_da_state_blk_t      *dblk,          /* data block */
1196        int                     *rval)          /* resulting block needs join */
1197{
1198        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1199        xfs_dir2_db_t           db;             /* data block number */
1200        struct xfs_buf          *dbp;           /* data block buffer */
1201        xfs_dir2_data_entry_t   *dep;           /* data block entry */
1202        xfs_inode_t             *dp;            /* incore directory inode */
1203        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1204        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1205        int                     longest;        /* longest data free entry */
1206        int                     off;            /* data block entry offset */
1207        xfs_mount_t             *mp;            /* filesystem mount point */
1208        int                     needlog;        /* need to log data header */
1209        int                     needscan;       /* need to rescan data frees */
1210        xfs_trans_t             *tp;            /* transaction pointer */
1211        struct xfs_dir2_data_free *bf;          /* bestfree table */
1212        struct xfs_dir3_icleaf_hdr leafhdr;
1213        struct xfs_dir2_leaf_entry *ents;
1214
1215        trace_xfs_dir2_leafn_remove(args, index);
1216
1217        dp = args->dp;
1218        tp = args->trans;
1219        mp = dp->i_mount;
1220        leaf = bp->b_addr;
1221        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1222        ents = xfs_dir3_leaf_ents_p(leaf);
1223
1224        /*
1225         * Point to the entry we're removing.
1226         */
1227        lep = &ents[index];
1228
1229        /*
1230         * Extract the data block and offset from the entry.
1231         */
1232        db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1233        ASSERT(dblk->blkno == db);
1234        off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
1235        ASSERT(dblk->index == off);
1236
1237        /*
1238         * Kill the leaf entry by marking it stale.
1239         * Log the leaf block changes.
1240         */
1241        leafhdr.stale++;
1242        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1243        xfs_dir3_leaf_log_header(tp, bp);
1244
1245        lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1246        xfs_dir3_leaf_log_ents(tp, bp, index, index);
1247
1248        /*
1249         * Make the data entry free.  Keep track of the longest freespace
1250         * in the data block in case it changes.
1251         */
1252        dbp = dblk->bp;
1253        hdr = dbp->b_addr;
1254        dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
1255        bf = xfs_dir3_data_bestfree_p(hdr);
1256        longest = be16_to_cpu(bf[0].length);
1257        needlog = needscan = 0;
1258        xfs_dir2_data_make_free(tp, dbp, off,
1259                xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1260        /*
1261         * Rescan the data block freespaces for bestfree.
1262         * Log the data block header if needed.
1263         */
1264        if (needscan)
1265                xfs_dir2_data_freescan(mp, hdr, &needlog);
1266        if (needlog)
1267                xfs_dir2_data_log_header(tp, dbp);
1268        xfs_dir3_data_check(dp, dbp);
1269        /*
1270         * If the longest data block freespace changes, need to update
1271         * the corresponding freeblock entry.
1272         */
1273        if (longest < be16_to_cpu(bf[0].length)) {
1274                int             error;          /* error return value */
1275                struct xfs_buf  *fbp;           /* freeblock buffer */
1276                xfs_dir2_db_t   fdb;            /* freeblock block number */
1277                int             findex;         /* index in freeblock entries */
1278                xfs_dir2_free_t *free;          /* freeblock structure */
1279
1280                /*
1281                 * Convert the data block number to a free block,
1282                 * read in the free block.
1283                 */
1284                fdb = xfs_dir2_db_to_fdb(mp, db);
1285                error = xfs_dir2_free_read(tp, dp, xfs_dir2_db_to_da(mp, fdb),
1286                                           &fbp);
1287                if (error)
1288                        return error;
1289                free = fbp->b_addr;
1290#ifdef DEBUG
1291        {
1292                struct xfs_dir3_icfree_hdr freehdr;
1293                xfs_dir3_free_hdr_from_disk(&freehdr, free);
1294                ASSERT(freehdr.firstdb == xfs_dir3_free_max_bests(mp) *
1295                                          (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
1296        }
1297#endif
1298                /*
1299                 * Calculate which entry we need to fix.
1300                 */
1301                findex = xfs_dir2_db_to_fdindex(mp, db);
1302                longest = be16_to_cpu(bf[0].length);
1303                /*
1304                 * If the data block is now empty we can get rid of it
1305                 * (usually).
1306                 */
1307                if (longest == mp->m_dirblksize -
1308                               xfs_dir3_data_entry_offset(hdr)) {
1309                        /*
1310                         * Try to punch out the data block.
1311                         */
1312                        error = xfs_dir2_shrink_inode(args, db, dbp);
1313                        if (error == 0) {
1314                                dblk->bp = NULL;
1315                                hdr = NULL;
1316                        }
1317                        /*
1318                         * We can get ENOSPC if there's no space reservation.
1319                         * In this case just drop the buffer and some one else
1320                         * will eventually get rid of the empty block.
1321                         */
1322                        else if (!(error == ENOSPC && args->total == 0))
1323                                return error;
1324                }
1325                /*
1326                 * If we got rid of the data block, we can eliminate that entry
1327                 * in the free block.
1328                 */
1329                error = xfs_dir3_data_block_free(args, hdr, free,
1330                                                 fdb, findex, fbp, longest);
1331                if (error)
1332                        return error;
1333        }
1334
1335        xfs_dir3_leaf_check(mp, bp);
1336        /*
1337         * Return indication of whether this leaf block is empty enough
1338         * to justify trying to join it with a neighbor.
1339         */
1340        *rval = (xfs_dir3_leaf_hdr_size(leaf) +
1341                 (uint)sizeof(ents[0]) * (leafhdr.count - leafhdr.stale)) <
1342                mp->m_dir_magicpct;
1343        return 0;
1344}
1345
1346/*
1347 * Split the leaf entries in the old block into old and new blocks.
1348 */
1349int                                             /* error */
1350xfs_dir2_leafn_split(
1351        xfs_da_state_t          *state,         /* btree cursor */
1352        xfs_da_state_blk_t      *oldblk,        /* original block */
1353        xfs_da_state_blk_t      *newblk)        /* newly created block */
1354{
1355        xfs_da_args_t           *args;          /* operation arguments */
1356        xfs_dablk_t             blkno;          /* new leaf block number */
1357        int                     error;          /* error return value */
1358        xfs_mount_t             *mp;            /* filesystem mount point */
1359
1360        /*
1361         * Allocate space for a new leaf node.
1362         */
1363        args = state->args;
1364        mp = args->dp->i_mount;
1365        ASSERT(args != NULL);
1366        ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1367        error = xfs_da_grow_inode(args, &blkno);
1368        if (error) {
1369                return error;
1370        }
1371        /*
1372         * Initialize the new leaf block.
1373         */
1374        error = xfs_dir3_leaf_get_buf(args, xfs_dir2_da_to_db(mp, blkno),
1375                                      &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1376        if (error)
1377                return error;
1378
1379        newblk->blkno = blkno;
1380        newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1381        /*
1382         * Rebalance the entries across the two leaves, link the new
1383         * block into the leaves.
1384         */
1385        xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1386        error = xfs_da3_blk_link(state, oldblk, newblk);
1387        if (error) {
1388                return error;
1389        }
1390        /*
1391         * Insert the new entry in the correct block.
1392         */
1393        if (state->inleaf)
1394                error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1395        else
1396                error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1397        /*
1398         * Update last hashval in each block since we added the name.
1399         */
1400        oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1401        newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1402        xfs_dir3_leaf_check(mp, oldblk->bp);
1403        xfs_dir3_leaf_check(mp, newblk->bp);
1404        return error;
1405}
1406
1407/*
1408 * Check a leaf block and its neighbors to see if the block should be
1409 * collapsed into one or the other neighbor.  Always keep the block
1410 * with the smaller block number.
1411 * If the current block is over 50% full, don't try to join it, return 0.
1412 * If the block is empty, fill in the state structure and return 2.
1413 * If it can be collapsed, fill in the state structure and return 1.
1414 * If nothing can be done, return 0.
1415 */
1416int                                             /* error */
1417xfs_dir2_leafn_toosmall(
1418        xfs_da_state_t          *state,         /* btree cursor */
1419        int                     *action)        /* resulting action to take */
1420{
1421        xfs_da_state_blk_t      *blk;           /* leaf block */
1422        xfs_dablk_t             blkno;          /* leaf block number */
1423        struct xfs_buf          *bp;            /* leaf buffer */
1424        int                     bytes;          /* bytes in use */
1425        int                     count;          /* leaf live entry count */
1426        int                     error;          /* error return value */
1427        int                     forward;        /* sibling block direction */
1428        int                     i;              /* sibling counter */
1429        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1430        int                     rval;           /* result from path_shift */
1431        struct xfs_dir3_icleaf_hdr leafhdr;
1432        struct xfs_dir2_leaf_entry *ents;
1433
1434        /*
1435         * Check for the degenerate case of the block being over 50% full.
1436         * If so, it's not worth even looking to see if we might be able
1437         * to coalesce with a sibling.
1438         */
1439        blk = &state->path.blk[state->path.active - 1];
1440        leaf = blk->bp->b_addr;
1441        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1442        ents = xfs_dir3_leaf_ents_p(leaf);
1443        xfs_dir3_leaf_check(state->args->dp->i_mount, blk->bp);
1444
1445        count = leafhdr.count - leafhdr.stale;
1446        bytes = xfs_dir3_leaf_hdr_size(leaf) + count * sizeof(ents[0]);
1447        if (bytes > (state->blocksize >> 1)) {
1448                /*
1449                 * Blk over 50%, don't try to join.
1450                 */
1451                *action = 0;
1452                return 0;
1453        }
1454        /*
1455         * Check for the degenerate case of the block being empty.
1456         * If the block is empty, we'll simply delete it, no need to
1457         * coalesce it with a sibling block.  We choose (arbitrarily)
1458         * to merge with the forward block unless it is NULL.
1459         */
1460        if (count == 0) {
1461                /*
1462                 * Make altpath point to the block we want to keep and
1463                 * path point to the block we want to drop (this one).
1464                 */
1465                forward = (leafhdr.forw != 0);
1466                memcpy(&state->altpath, &state->path, sizeof(state->path));
1467                error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1468                        &rval);
1469                if (error)
1470                        return error;
1471                *action = rval ? 2 : 0;
1472                return 0;
1473        }
1474        /*
1475         * Examine each sibling block to see if we can coalesce with
1476         * at least 25% free space to spare.  We need to figure out
1477         * whether to merge with the forward or the backward block.
1478         * We prefer coalescing with the lower numbered sibling so as
1479         * to shrink a directory over time.
1480         */
1481        forward = leafhdr.forw < leafhdr.back;
1482        for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1483                struct xfs_dir3_icleaf_hdr hdr2;
1484
1485                blkno = forward ? leafhdr.forw : leafhdr.back;
1486                if (blkno == 0)
1487                        continue;
1488                /*
1489                 * Read the sibling leaf block.
1490                 */
1491                error = xfs_dir3_leafn_read(state->args->trans, state->args->dp,
1492                                            blkno, -1, &bp);
1493                if (error)
1494                        return error;
1495
1496                /*
1497                 * Count bytes in the two blocks combined.
1498                 */
1499                count = leafhdr.count - leafhdr.stale;
1500                bytes = state->blocksize - (state->blocksize >> 2);
1501
1502                leaf = bp->b_addr;
1503                xfs_dir3_leaf_hdr_from_disk(&hdr2, leaf);
1504                ents = xfs_dir3_leaf_ents_p(leaf);
1505                count += hdr2.count - hdr2.stale;
1506                bytes -= count * sizeof(ents[0]);
1507
1508                /*
1509                 * Fits with at least 25% to spare.
1510                 */
1511                if (bytes >= 0)
1512                        break;
1513                xfs_trans_brelse(state->args->trans, bp);
1514        }
1515        /*
1516         * Didn't like either block, give up.
1517         */
1518        if (i >= 2) {
1519                *action = 0;
1520                return 0;
1521        }
1522
1523        /*
1524         * Make altpath point to the block we want to keep (the lower
1525         * numbered block) and path point to the block we want to drop.
1526         */
1527        memcpy(&state->altpath, &state->path, sizeof(state->path));
1528        if (blkno < blk->blkno)
1529                error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1530                        &rval);
1531        else
1532                error = xfs_da3_path_shift(state, &state->path, forward, 0,
1533                        &rval);
1534        if (error) {
1535                return error;
1536        }
1537        *action = rval ? 0 : 1;
1538        return 0;
1539}
1540
1541/*
1542 * Move all the leaf entries from drop_blk to save_blk.
1543 * This is done as part of a join operation.
1544 */
1545void
1546xfs_dir2_leafn_unbalance(
1547        xfs_da_state_t          *state,         /* cursor */
1548        xfs_da_state_blk_t      *drop_blk,      /* dead block */
1549        xfs_da_state_blk_t      *save_blk)      /* surviving block */
1550{
1551        xfs_da_args_t           *args;          /* operation arguments */
1552        xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1553        xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1554        struct xfs_dir3_icleaf_hdr savehdr;
1555        struct xfs_dir3_icleaf_hdr drophdr;
1556        struct xfs_dir2_leaf_entry *sents;
1557        struct xfs_dir2_leaf_entry *dents;
1558
1559        args = state->args;
1560        ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1561        ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1562        drop_leaf = drop_blk->bp->b_addr;
1563        save_leaf = save_blk->bp->b_addr;
1564
1565        xfs_dir3_leaf_hdr_from_disk(&savehdr, save_leaf);
1566        xfs_dir3_leaf_hdr_from_disk(&drophdr, drop_leaf);
1567        sents = xfs_dir3_leaf_ents_p(save_leaf);
1568        dents = xfs_dir3_leaf_ents_p(drop_leaf);
1569
1570        /*
1571         * If there are any stale leaf entries, take this opportunity
1572         * to purge them.
1573         */
1574        if (drophdr.stale)
1575                xfs_dir3_leaf_compact(args, &drophdr, drop_blk->bp);
1576        if (savehdr.stale)
1577                xfs_dir3_leaf_compact(args, &savehdr, save_blk->bp);
1578
1579        /*
1580         * Move the entries from drop to the appropriate end of save.
1581         */
1582        drop_blk->hashval = be32_to_cpu(dents[drophdr.count - 1].hashval);
1583        if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1584                xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1585                                        save_blk->bp, &savehdr, sents, 0,
1586                                        drophdr.count);
1587        else
1588                xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1589                                        save_blk->bp, &savehdr, sents,
1590                                        savehdr.count, drophdr.count);
1591        save_blk->hashval = be32_to_cpu(sents[savehdr.count - 1].hashval);
1592
1593        /* log the changes made when moving the entries */
1594        xfs_dir3_leaf_hdr_to_disk(save_leaf, &savehdr);
1595        xfs_dir3_leaf_hdr_to_disk(drop_leaf, &drophdr);
1596        xfs_dir3_leaf_log_header(args->trans, save_blk->bp);
1597        xfs_dir3_leaf_log_header(args->trans, drop_blk->bp);
1598
1599        xfs_dir3_leaf_check(args->dp->i_mount, save_blk->bp);
1600        xfs_dir3_leaf_check(args->dp->i_mount, drop_blk->bp);
1601}
1602
1603/*
1604 * Top-level node form directory addname routine.
1605 */
1606int                                             /* error */
1607xfs_dir2_node_addname(
1608        xfs_da_args_t           *args)          /* operation arguments */
1609{
1610        xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1611        int                     error;          /* error return value */
1612        int                     rval;           /* sub-return value */
1613        xfs_da_state_t          *state;         /* btree cursor */
1614
1615        trace_xfs_dir2_node_addname(args);
1616
1617        /*
1618         * Allocate and initialize the state (btree cursor).
1619         */
1620        state = xfs_da_state_alloc();
1621        state->args = args;
1622        state->mp = args->dp->i_mount;
1623        state->blocksize = state->mp->m_dirblksize;
1624        state->node_ents = state->mp->m_dir_node_ents;
1625        /*
1626         * Look up the name.  We're not supposed to find it, but
1627         * this gives us the insertion point.
1628         */
1629        error = xfs_da3_node_lookup_int(state, &rval);
1630        if (error)
1631                rval = error;
1632        if (rval != ENOENT) {
1633                goto done;
1634        }
1635        /*
1636         * Add the data entry to a data block.
1637         * Extravalid is set to a freeblock found by lookup.
1638         */
1639        rval = xfs_dir2_node_addname_int(args,
1640                state->extravalid ? &state->extrablk : NULL);
1641        if (rval) {
1642                goto done;
1643        }
1644        blk = &state->path.blk[state->path.active - 1];
1645        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1646        /*
1647         * Add the new leaf entry.
1648         */
1649        rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1650        if (rval == 0) {
1651                /*
1652                 * It worked, fix the hash values up the btree.
1653                 */
1654                if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1655                        xfs_da3_fixhashpath(state, &state->path);
1656        } else {
1657                /*
1658                 * It didn't work, we need to split the leaf block.
1659                 */
1660                if (args->total == 0) {
1661                        ASSERT(rval == ENOSPC);
1662                        goto done;
1663                }
1664                /*
1665                 * Split the leaf block and insert the new entry.
1666                 */
1667                rval = xfs_da3_split(state);
1668        }
1669done:
1670        xfs_da_state_free(state);
1671        return rval;
1672}
1673
1674/*
1675 * Add the data entry for a node-format directory name addition.
1676 * The leaf entry is added in xfs_dir2_leafn_add.
1677 * We may enter with a freespace block that the lookup found.
1678 */
1679static int                                      /* error */
1680xfs_dir2_node_addname_int(
1681        xfs_da_args_t           *args,          /* operation arguments */
1682        xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1683{
1684        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1685        xfs_dir2_db_t           dbno;           /* data block number */
1686        struct xfs_buf          *dbp;           /* data block buffer */
1687        xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1688        xfs_inode_t             *dp;            /* incore directory inode */
1689        xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1690        int                     error;          /* error return value */
1691        xfs_dir2_db_t           fbno;           /* freespace block number */
1692        struct xfs_buf          *fbp;           /* freespace buffer */
1693        int                     findex;         /* freespace entry index */
1694        xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1695        xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1696        xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1697        int                     length;         /* length of the new entry */
1698        int                     logfree;        /* need to log free entry */
1699        xfs_mount_t             *mp;            /* filesystem mount point */
1700        int                     needlog;        /* need to log data header */
1701        int                     needscan;       /* need to rescan data frees */
1702        __be16                  *tagp;          /* data entry tag pointer */
1703        xfs_trans_t             *tp;            /* transaction pointer */
1704        __be16                  *bests;
1705        struct xfs_dir3_icfree_hdr freehdr;
1706        struct xfs_dir2_data_free *bf;
1707
1708        dp = args->dp;
1709        mp = dp->i_mount;
1710        tp = args->trans;
1711        length = xfs_dir2_data_entsize(args->namelen);
1712        /*
1713         * If we came in with a freespace block that means that lookup
1714         * found an entry with our hash value.  This is the freespace
1715         * block for that data entry.
1716         */
1717        if (fblk) {
1718                fbp = fblk->bp;
1719                /*
1720                 * Remember initial freespace block number.
1721                 */
1722                ifbno = fblk->blkno;
1723                free = fbp->b_addr;
1724                findex = fblk->index;
1725                bests = xfs_dir3_free_bests_p(mp, free);
1726                xfs_dir3_free_hdr_from_disk(&freehdr, free);
1727
1728                /*
1729                 * This means the free entry showed that the data block had
1730                 * space for our entry, so we remembered it.
1731                 * Use that data block.
1732                 */
1733                if (findex >= 0) {
1734                        ASSERT(findex < freehdr.nvalid);
1735                        ASSERT(be16_to_cpu(bests[findex]) != NULLDATAOFF);
1736                        ASSERT(be16_to_cpu(bests[findex]) >= length);
1737                        dbno = freehdr.firstdb + findex;
1738                } else {
1739                        /*
1740                         * The data block looked at didn't have enough room.
1741                         * We'll start at the beginning of the freespace entries.
1742                         */
1743                        dbno = -1;
1744                        findex = 0;
1745                }
1746        } else {
1747                /*
1748                 * Didn't come in with a freespace block, so no data block.
1749                 */
1750                ifbno = dbno = -1;
1751                fbp = NULL;
1752                findex = 0;
1753        }
1754
1755        /*
1756         * If we don't have a data block yet, we're going to scan the
1757         * freespace blocks looking for one.  Figure out what the
1758         * highest freespace block number is.
1759         */
1760        if (dbno == -1) {
1761                xfs_fileoff_t   fo;             /* freespace block number */
1762
1763                if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1764                        return error;
1765                lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1766                fbno = ifbno;
1767        }
1768        /*
1769         * While we haven't identified a data block, search the freeblock
1770         * data for a good data block.  If we find a null freeblock entry,
1771         * indicating a hole in the data blocks, remember that.
1772         */
1773        while (dbno == -1) {
1774                /*
1775                 * If we don't have a freeblock in hand, get the next one.
1776                 */
1777                if (fbp == NULL) {
1778                        /*
1779                         * Happens the first time through unless lookup gave
1780                         * us a freespace block to start with.
1781                         */
1782                        if (++fbno == 0)
1783                                fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1784                        /*
1785                         * If it's ifbno we already looked at it.
1786                         */
1787                        if (fbno == ifbno)
1788                                fbno++;
1789                        /*
1790                         * If it's off the end we're done.
1791                         */
1792                        if (fbno >= lastfbno)
1793                                break;
1794                        /*
1795                         * Read the block.  There can be holes in the
1796                         * freespace blocks, so this might not succeed.
1797                         * This should be really rare, so there's no reason
1798                         * to avoid it.
1799                         */
1800                        error = xfs_dir2_free_try_read(tp, dp,
1801                                                xfs_dir2_db_to_da(mp, fbno),
1802                                                &fbp);
1803                        if (error)
1804                                return error;
1805                        if (!fbp)
1806                                continue;
1807                        free = fbp->b_addr;
1808                        findex = 0;
1809                }
1810                /*
1811                 * Look at the current free entry.  Is it good enough?
1812                 *
1813                 * The bests initialisation should be where the bufer is read in
1814                 * the above branch. But gcc is too stupid to realise that bests
1815                 * and the freehdr are actually initialised if they are placed
1816                 * there, so we have to do it here to avoid warnings. Blech.
1817                 */
1818                bests = xfs_dir3_free_bests_p(mp, free);
1819                xfs_dir3_free_hdr_from_disk(&freehdr, free);
1820                if (be16_to_cpu(bests[findex]) != NULLDATAOFF &&
1821                    be16_to_cpu(bests[findex]) >= length)
1822                        dbno = freehdr.firstdb + findex;
1823                else {
1824                        /*
1825                         * Are we done with the freeblock?
1826                         */
1827                        if (++findex == freehdr.nvalid) {
1828                                /*
1829                                 * Drop the block.
1830                                 */
1831                                xfs_trans_brelse(tp, fbp);
1832                                fbp = NULL;
1833                                if (fblk && fblk->bp)
1834                                        fblk->bp = NULL;
1835                        }
1836                }
1837        }
1838        /*
1839         * If we don't have a data block, we need to allocate one and make
1840         * the freespace entries refer to it.
1841         */
1842        if (unlikely(dbno == -1)) {
1843                /*
1844                 * Not allowed to allocate, return failure.
1845                 */
1846                if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
1847                        return XFS_ERROR(ENOSPC);
1848
1849                /*
1850                 * Allocate and initialize the new data block.
1851                 */
1852                if (unlikely((error = xfs_dir2_grow_inode(args,
1853                                                         XFS_DIR2_DATA_SPACE,
1854                                                         &dbno)) ||
1855                    (error = xfs_dir3_data_init(args, dbno, &dbp))))
1856                        return error;
1857
1858                /*
1859                 * If (somehow) we have a freespace block, get rid of it.
1860                 */
1861                if (fbp)
1862                        xfs_trans_brelse(tp, fbp);
1863                if (fblk && fblk->bp)
1864                        fblk->bp = NULL;
1865
1866                /*
1867                 * Get the freespace block corresponding to the data block
1868                 * that was just allocated.
1869                 */
1870                fbno = xfs_dir2_db_to_fdb(mp, dbno);
1871                error = xfs_dir2_free_try_read(tp, dp,
1872                                               xfs_dir2_db_to_da(mp, fbno),
1873                                               &fbp);
1874                if (error)
1875                        return error;
1876
1877                /*
1878                 * If there wasn't a freespace block, the read will
1879                 * return a NULL fbp.  Allocate and initialize a new one.
1880                 */
1881                if (!fbp) {
1882                        error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1883                                                    &fbno);
1884                        if (error)
1885                                return error;
1886
1887                        if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1888                                xfs_alert(mp,
1889                        "%s: dir ino %llu needed freesp block %lld for\n"
1890                        "  data block %lld, got %lld ifbno %llu lastfbno %d",
1891                                        __func__, (unsigned long long)dp->i_ino,
1892                                        (long long)xfs_dir2_db_to_fdb(mp, dbno),
1893                                        (long long)dbno, (long long)fbno,
1894                                        (unsigned long long)ifbno, lastfbno);
1895                                if (fblk) {
1896                                        xfs_alert(mp,
1897                                " fblk 0x%p blkno %llu index %d magic 0x%x",
1898                                                fblk,
1899                                                (unsigned long long)fblk->blkno,
1900                                                fblk->index,
1901                                                fblk->magic);
1902                                } else {
1903                                        xfs_alert(mp, " ... fblk is NULL");
1904                                }
1905                                XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1906                                                 XFS_ERRLEVEL_LOW, mp);
1907                                return XFS_ERROR(EFSCORRUPTED);
1908                        }
1909
1910                        /*
1911                         * Get a buffer for the new block.
1912                         */
1913                        error = xfs_dir3_free_get_buf(tp, dp, fbno, &fbp);
1914                        if (error)
1915                                return error;
1916                        free = fbp->b_addr;
1917                        bests = xfs_dir3_free_bests_p(mp, free);
1918                        xfs_dir3_free_hdr_from_disk(&freehdr, free);
1919
1920                        /*
1921                         * Remember the first slot as our empty slot.
1922                         */
1923                        freehdr.firstdb = (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1924                                        xfs_dir3_free_max_bests(mp);
1925                } else {
1926                        free = fbp->b_addr;
1927                        bests = xfs_dir3_free_bests_p(mp, free);
1928                        xfs_dir3_free_hdr_from_disk(&freehdr, free);
1929                }
1930
1931                /*
1932                 * Set the freespace block index from the data block number.
1933                 */
1934                findex = xfs_dir2_db_to_fdindex(mp, dbno);
1935                /*
1936                 * If it's after the end of the current entries in the
1937                 * freespace block, extend that table.
1938                 */
1939                if (findex >= freehdr.nvalid) {
1940                        ASSERT(findex < xfs_dir3_free_max_bests(mp));
1941                        freehdr.nvalid = findex + 1;
1942                        /*
1943                         * Tag new entry so nused will go up.
1944                         */
1945                        bests[findex] = cpu_to_be16(NULLDATAOFF);
1946                }
1947                /*
1948                 * If this entry was for an empty data block
1949                 * (this should always be true) then update the header.
1950                 */
1951                if (bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1952                        freehdr.nused++;
1953                        xfs_dir3_free_hdr_to_disk(fbp->b_addr, &freehdr);
1954                        xfs_dir2_free_log_header(tp, fbp);
1955                }
1956                /*
1957                 * Update the real value in the table.
1958                 * We haven't allocated the data entry yet so this will
1959                 * change again.
1960                 */
1961                hdr = dbp->b_addr;
1962                bf = xfs_dir3_data_bestfree_p(hdr);
1963                bests[findex] = bf[0].length;
1964                logfree = 1;
1965        }
1966        /*
1967         * We had a data block so we don't have to make a new one.
1968         */
1969        else {
1970                /*
1971                 * If just checking, we succeeded.
1972                 */
1973                if (args->op_flags & XFS_DA_OP_JUSTCHECK)
1974                        return 0;
1975
1976                /*
1977                 * Read the data block in.
1978                 */
1979                error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1980                                           -1, &dbp);
1981                if (error)
1982                        return error;
1983                hdr = dbp->b_addr;
1984                bf = xfs_dir3_data_bestfree_p(hdr);
1985                logfree = 0;
1986        }
1987        ASSERT(be16_to_cpu(bf[0].length) >= length);
1988        /*
1989         * Point to the existing unused space.
1990         */
1991        dup = (xfs_dir2_data_unused_t *)
1992              ((char *)hdr + be16_to_cpu(bf[0].offset));
1993        needscan = needlog = 0;
1994        /*
1995         * Mark the first part of the unused space, inuse for us.
1996         */
1997        xfs_dir2_data_use_free(tp, dbp, dup,
1998                (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
1999                &needlog, &needscan);
2000        /*
2001         * Fill in the new entry and log it.
2002         */
2003        dep = (xfs_dir2_data_entry_t *)dup;
2004        dep->inumber = cpu_to_be64(args->inumber);
2005        dep->namelen = args->namelen;
2006        memcpy(dep->name, args->name, dep->namelen);
2007        tagp = xfs_dir2_data_entry_tag_p(dep);
2008        *tagp = cpu_to_be16((char *)dep - (char *)hdr);
2009        xfs_dir2_data_log_entry(tp, dbp, dep);
2010        /*
2011         * Rescan the block for bestfree if needed.
2012         */
2013        if (needscan)
2014                xfs_dir2_data_freescan(mp, hdr, &needlog);
2015        /*
2016         * Log the data block header if needed.
2017         */
2018        if (needlog)
2019                xfs_dir2_data_log_header(tp, dbp);
2020        /*
2021         * If the freespace entry is now wrong, update it.
2022         */
2023        bests = xfs_dir3_free_bests_p(mp, free); /* gcc is so stupid */
2024        if (be16_to_cpu(bests[findex]) != be16_to_cpu(bf[0].length)) {
2025                bests[findex] = bf[0].length;
2026                logfree = 1;
2027        }
2028        /*
2029         * Log the freespace entry if needed.
2030         */
2031        if (logfree)
2032                xfs_dir2_free_log_bests(tp, fbp, findex, findex);
2033        /*
2034         * Return the data block and offset in args, then drop the data block.
2035         */
2036        args->blkno = (xfs_dablk_t)dbno;
2037        args->index = be16_to_cpu(*tagp);
2038        return 0;
2039}
2040
2041/*
2042 * Lookup an entry in a node-format directory.
2043 * All the real work happens in xfs_da3_node_lookup_int.
2044 * The only real output is the inode number of the entry.
2045 */
2046int                                             /* error */
2047xfs_dir2_node_lookup(
2048        xfs_da_args_t   *args)                  /* operation arguments */
2049{
2050        int             error;                  /* error return value */
2051        int             i;                      /* btree level */
2052        int             rval;                   /* operation return value */
2053        xfs_da_state_t  *state;                 /* btree cursor */
2054
2055        trace_xfs_dir2_node_lookup(args);
2056
2057        /*
2058         * Allocate and initialize the btree cursor.
2059         */
2060        state = xfs_da_state_alloc();
2061        state->args = args;
2062        state->mp = args->dp->i_mount;
2063        state->blocksize = state->mp->m_dirblksize;
2064        state->node_ents = state->mp->m_dir_node_ents;
2065        /*
2066         * Fill in the path to the entry in the cursor.
2067         */
2068        error = xfs_da3_node_lookup_int(state, &rval);
2069        if (error)
2070                rval = error;
2071        else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
2072                /* If a CI match, dup the actual name and return EEXIST */
2073                xfs_dir2_data_entry_t   *dep;
2074
2075                dep = (xfs_dir2_data_entry_t *)
2076                        ((char *)state->extrablk.bp->b_addr +
2077                                                 state->extrablk.index);
2078                rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
2079        }
2080        /*
2081         * Release the btree blocks and leaf block.
2082         */
2083        for (i = 0; i < state->path.active; i++) {
2084                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2085                state->path.blk[i].bp = NULL;
2086        }
2087        /*
2088         * Release the data block if we have it.
2089         */
2090        if (state->extravalid && state->extrablk.bp) {
2091                xfs_trans_brelse(args->trans, state->extrablk.bp);
2092                state->extrablk.bp = NULL;
2093        }
2094        xfs_da_state_free(state);
2095        return rval;
2096}
2097
2098/*
2099 * Remove an entry from a node-format directory.
2100 */
2101int                                             /* error */
2102xfs_dir2_node_removename(
2103        xfs_da_args_t           *args)          /* operation arguments */
2104{
2105        xfs_da_state_blk_t      *blk;           /* leaf block */
2106        int                     error;          /* error return value */
2107        int                     rval;           /* operation return value */
2108        xfs_da_state_t          *state;         /* btree cursor */
2109
2110        trace_xfs_dir2_node_removename(args);
2111
2112        /*
2113         * Allocate and initialize the btree cursor.
2114         */
2115        state = xfs_da_state_alloc();
2116        state->args = args;
2117        state->mp = args->dp->i_mount;
2118        state->blocksize = state->mp->m_dirblksize;
2119        state->node_ents = state->mp->m_dir_node_ents;
2120        /*
2121         * Look up the entry we're deleting, set up the cursor.
2122         */
2123        error = xfs_da3_node_lookup_int(state, &rval);
2124        if (error)
2125                rval = error;
2126        /*
2127         * Didn't find it, upper layer screwed up.
2128         */
2129        if (rval != EEXIST) {
2130                xfs_da_state_free(state);
2131                return rval;
2132        }
2133        blk = &state->path.blk[state->path.active - 1];
2134        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2135        ASSERT(state->extravalid);
2136        /*
2137         * Remove the leaf and data entries.
2138         * Extrablk refers to the data block.
2139         */
2140        error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
2141                &state->extrablk, &rval);
2142        if (error)
2143                return error;
2144        /*
2145         * Fix the hash values up the btree.
2146         */
2147        xfs_da3_fixhashpath(state, &state->path);
2148        /*
2149         * If we need to join leaf blocks, do it.
2150         */
2151        if (rval && state->path.active > 1)
2152                error = xfs_da3_join(state);
2153        /*
2154         * If no errors so far, try conversion to leaf format.
2155         */
2156        if (!error)
2157                error = xfs_dir2_node_to_leaf(state);
2158        xfs_da_state_free(state);
2159        return error;
2160}
2161
2162/*
2163 * Replace an entry's inode number in a node-format directory.
2164 */
2165int                                             /* error */
2166xfs_dir2_node_replace(
2167        xfs_da_args_t           *args)          /* operation arguments */
2168{
2169        xfs_da_state_blk_t      *blk;           /* leaf block */
2170        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
2171        xfs_dir2_data_entry_t   *dep;           /* data entry changed */
2172        int                     error;          /* error return value */
2173        int                     i;              /* btree level */
2174        xfs_ino_t               inum;           /* new inode number */
2175        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2176        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
2177        int                     rval;           /* internal return value */
2178        xfs_da_state_t          *state;         /* btree cursor */
2179
2180        trace_xfs_dir2_node_replace(args);
2181
2182        /*
2183         * Allocate and initialize the btree cursor.
2184         */
2185        state = xfs_da_state_alloc();
2186        state->args = args;
2187        state->mp = args->dp->i_mount;
2188        state->blocksize = state->mp->m_dirblksize;
2189        state->node_ents = state->mp->m_dir_node_ents;
2190        inum = args->inumber;
2191        /*
2192         * Lookup the entry to change in the btree.
2193         */
2194        error = xfs_da3_node_lookup_int(state, &rval);
2195        if (error) {
2196                rval = error;
2197        }
2198        /*
2199         * It should be found, since the vnodeops layer has looked it up
2200         * and locked it.  But paranoia is good.
2201         */
2202        if (rval == EEXIST) {
2203                struct xfs_dir2_leaf_entry *ents;
2204                /*
2205                 * Find the leaf entry.
2206                 */
2207                blk = &state->path.blk[state->path.active - 1];
2208                ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2209                leaf = blk->bp->b_addr;
2210                ents = xfs_dir3_leaf_ents_p(leaf);
2211                lep = &ents[blk->index];
2212                ASSERT(state->extravalid);
2213                /*
2214                 * Point to the data entry.
2215                 */
2216                hdr = state->extrablk.bp->b_addr;
2217                ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
2218                       hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
2219                dep = (xfs_dir2_data_entry_t *)
2220                      ((char *)hdr +
2221                       xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
2222                ASSERT(inum != be64_to_cpu(dep->inumber));
2223                /*
2224                 * Fill in the new inode number and log the entry.
2225                 */
2226                dep->inumber = cpu_to_be64(inum);
2227                xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
2228                rval = 0;
2229        }
2230        /*
2231         * Didn't find it, and we're holding a data block.  Drop it.
2232         */
2233        else if (state->extravalid) {
2234                xfs_trans_brelse(args->trans, state->extrablk.bp);
2235                state->extrablk.bp = NULL;
2236        }
2237        /*
2238         * Release all the buffers in the cursor.
2239         */
2240        for (i = 0; i < state->path.active; i++) {
2241                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2242                state->path.blk[i].bp = NULL;
2243        }
2244        xfs_da_state_free(state);
2245        return rval;
2246}
2247
2248/*
2249 * Trim off a trailing empty freespace block.
2250 * Return (in rvalp) 1 if we did it, 0 if not.
2251 */
2252int                                             /* error */
2253xfs_dir2_node_trim_free(
2254        xfs_da_args_t           *args,          /* operation arguments */
2255        xfs_fileoff_t           fo,             /* free block number */
2256        int                     *rvalp)         /* out: did something */
2257{
2258        struct xfs_buf          *bp;            /* freespace buffer */
2259        xfs_inode_t             *dp;            /* incore directory inode */
2260        int                     error;          /* error return code */
2261        xfs_dir2_free_t         *free;          /* freespace structure */
2262        xfs_mount_t             *mp;            /* filesystem mount point */
2263        xfs_trans_t             *tp;            /* transaction pointer */
2264        struct xfs_dir3_icfree_hdr freehdr;
2265
2266        dp = args->dp;
2267        mp = dp->i_mount;
2268        tp = args->trans;
2269        /*
2270         * Read the freespace block.
2271         */
2272        error = xfs_dir2_free_try_read(tp, dp, fo, &bp);
2273        if (error)
2274                return error;
2275        /*
2276         * There can be holes in freespace.  If fo is a hole, there's
2277         * nothing to do.
2278         */
2279        if (!bp)
2280                return 0;
2281        free = bp->b_addr;
2282        xfs_dir3_free_hdr_from_disk(&freehdr, free);
2283
2284        /*
2285         * If there are used entries, there's nothing to do.
2286         */
2287        if (freehdr.nused > 0) {
2288                xfs_trans_brelse(tp, bp);
2289                *rvalp = 0;
2290                return 0;
2291        }
2292        /*
2293         * Blow the block away.
2294         */
2295        if ((error =
2296            xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
2297                    bp))) {
2298                /*
2299                 * Can't fail with ENOSPC since that only happens with no
2300                 * space reservation, when breaking up an extent into two
2301                 * pieces.  This is the last block of an extent.
2302                 */
2303                ASSERT(error != ENOSPC);
2304                xfs_trans_brelse(tp, bp);
2305                return error;
2306        }
2307        /*
2308         * Return that we succeeded.
2309         */
2310        *rvalp = 1;
2311        return 0;
2312}
2313
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