linux/fs/xfs/libxfs/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_format.h"
  22#include "xfs_log_format.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_mount.h"
  25#include "xfs_da_format.h"
  26#include "xfs_da_btree.h"
  27#include "xfs_inode.h"
  28#include "xfs_bmap.h"
  29#include "xfs_dir2.h"
  30#include "xfs_dir2_priv.h"
  31#include "xfs_error.h"
  32#include "xfs_trace.h"
  33#include "xfs_trans.h"
  34#include "xfs_buf_item.h"
  35#include "xfs_cksum.h"
  36#include "xfs_log.h"
  37
  38/*
  39 * Function declarations.
  40 */
  41static int xfs_dir2_leafn_add(struct xfs_buf *bp, xfs_da_args_t *args,
  42                              int index);
  43static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
  44                                     xfs_da_state_blk_t *blk1,
  45                                     xfs_da_state_blk_t *blk2);
  46static int xfs_dir2_leafn_remove(xfs_da_args_t *args, struct xfs_buf *bp,
  47                                 int index, xfs_da_state_blk_t *dblk,
  48                                 int *rval);
  49static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
  50                                     xfs_da_state_blk_t *fblk);
  51
  52/*
  53 * Check internal consistency of a leafn block.
  54 */
  55#ifdef DEBUG
  56#define xfs_dir3_leaf_check(dp, bp) \
  57do { \
  58        if (!xfs_dir3_leafn_check((dp), (bp))) \
  59                ASSERT(0); \
  60} while (0);
  61
  62static bool
  63xfs_dir3_leafn_check(
  64        struct xfs_inode        *dp,
  65        struct xfs_buf          *bp)
  66{
  67        struct xfs_dir2_leaf    *leaf = bp->b_addr;
  68        struct xfs_dir3_icleaf_hdr leafhdr;
  69
  70        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
  71
  72        if (leafhdr.magic == XFS_DIR3_LEAFN_MAGIC) {
  73                struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
  74                if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
  75                        return false;
  76        } else if (leafhdr.magic != XFS_DIR2_LEAFN_MAGIC)
  77                return false;
  78
  79        return xfs_dir3_leaf_check_int(dp->i_mount, dp, &leafhdr, leaf);
  80}
  81#else
  82#define xfs_dir3_leaf_check(dp, bp)
  83#endif
  84
  85static bool
  86xfs_dir3_free_verify(
  87        struct xfs_buf          *bp)
  88{
  89        struct xfs_mount        *mp = bp->b_target->bt_mount;
  90        struct xfs_dir2_free_hdr *hdr = bp->b_addr;
  91
  92        if (xfs_sb_version_hascrc(&mp->m_sb)) {
  93                struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
  94
  95                if (hdr3->magic != cpu_to_be32(XFS_DIR3_FREE_MAGIC))
  96                        return false;
  97                if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
  98                        return false;
  99                if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
 100                        return false;
 101                if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
 102                        return false;
 103        } else {
 104                if (hdr->magic != cpu_to_be32(XFS_DIR2_FREE_MAGIC))
 105                        return false;
 106        }
 107
 108        /* XXX: should bounds check the xfs_dir3_icfree_hdr here */
 109
 110        return true;
 111}
 112
 113static void
 114xfs_dir3_free_read_verify(
 115        struct xfs_buf  *bp)
 116{
 117        struct xfs_mount        *mp = bp->b_target->bt_mount;
 118
 119        if (xfs_sb_version_hascrc(&mp->m_sb) &&
 120            !xfs_buf_verify_cksum(bp, XFS_DIR3_FREE_CRC_OFF))
 121                xfs_buf_ioerror(bp, -EFSBADCRC);
 122        else if (!xfs_dir3_free_verify(bp))
 123                xfs_buf_ioerror(bp, -EFSCORRUPTED);
 124
 125        if (bp->b_error)
 126                xfs_verifier_error(bp);
 127}
 128
 129static void
 130xfs_dir3_free_write_verify(
 131        struct xfs_buf  *bp)
 132{
 133        struct xfs_mount        *mp = bp->b_target->bt_mount;
 134        struct xfs_buf_log_item *bip = bp->b_fspriv;
 135        struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
 136
 137        if (!xfs_dir3_free_verify(bp)) {
 138                xfs_buf_ioerror(bp, -EFSCORRUPTED);
 139                xfs_verifier_error(bp);
 140                return;
 141        }
 142
 143        if (!xfs_sb_version_hascrc(&mp->m_sb))
 144                return;
 145
 146        if (bip)
 147                hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
 148
 149        xfs_buf_update_cksum(bp, XFS_DIR3_FREE_CRC_OFF);
 150}
 151
 152const struct xfs_buf_ops xfs_dir3_free_buf_ops = {
 153        .name = "xfs_dir3_free",
 154        .verify_read = xfs_dir3_free_read_verify,
 155        .verify_write = xfs_dir3_free_write_verify,
 156};
 157
 158/* Everything ok in the free block header? */
 159static bool
 160xfs_dir3_free_header_check(
 161        struct xfs_inode        *dp,
 162        xfs_dablk_t             fbno,
 163        struct xfs_buf          *bp)
 164{
 165        struct xfs_mount        *mp = dp->i_mount;
 166        unsigned int            firstdb;
 167        int                     maxbests;
 168
 169        maxbests = dp->d_ops->free_max_bests(mp->m_dir_geo);
 170        firstdb = (xfs_dir2_da_to_db(mp->m_dir_geo, fbno) -
 171                   xfs_dir2_byte_to_db(mp->m_dir_geo, XFS_DIR2_FREE_OFFSET)) *
 172                        maxbests;
 173        if (xfs_sb_version_hascrc(&mp->m_sb)) {
 174                struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 175
 176                if (be32_to_cpu(hdr3->firstdb) != firstdb)
 177                        return false;
 178                if (be32_to_cpu(hdr3->nvalid) > maxbests)
 179                        return false;
 180                if (be32_to_cpu(hdr3->nvalid) < be32_to_cpu(hdr3->nused))
 181                        return false;
 182        } else {
 183                struct xfs_dir2_free_hdr *hdr = bp->b_addr;
 184
 185                if (be32_to_cpu(hdr->firstdb) != firstdb)
 186                        return false;
 187                if (be32_to_cpu(hdr->nvalid) > maxbests)
 188                        return false;
 189                if (be32_to_cpu(hdr->nvalid) < be32_to_cpu(hdr->nused))
 190                        return false;
 191        }
 192        return true;
 193}
 194
 195static int
 196__xfs_dir3_free_read(
 197        struct xfs_trans        *tp,
 198        struct xfs_inode        *dp,
 199        xfs_dablk_t             fbno,
 200        xfs_daddr_t             mappedbno,
 201        struct xfs_buf          **bpp)
 202{
 203        int                     err;
 204
 205        err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 206                                XFS_DATA_FORK, &xfs_dir3_free_buf_ops);
 207        if (err || !*bpp)
 208                return err;
 209
 210        /* Check things that we can't do in the verifier. */
 211        if (!xfs_dir3_free_header_check(dp, fbno, *bpp)) {
 212                xfs_buf_ioerror(*bpp, -EFSCORRUPTED);
 213                xfs_verifier_error(*bpp);
 214                xfs_trans_brelse(tp, *bpp);
 215                return -EFSCORRUPTED;
 216        }
 217
 218        /* try read returns without an error or *bpp if it lands in a hole */
 219        if (tp)
 220                xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_FREE_BUF);
 221
 222        return 0;
 223}
 224
 225int
 226xfs_dir2_free_read(
 227        struct xfs_trans        *tp,
 228        struct xfs_inode        *dp,
 229        xfs_dablk_t             fbno,
 230        struct xfs_buf          **bpp)
 231{
 232        return __xfs_dir3_free_read(tp, dp, fbno, -1, bpp);
 233}
 234
 235static int
 236xfs_dir2_free_try_read(
 237        struct xfs_trans        *tp,
 238        struct xfs_inode        *dp,
 239        xfs_dablk_t             fbno,
 240        struct xfs_buf          **bpp)
 241{
 242        return __xfs_dir3_free_read(tp, dp, fbno, -2, bpp);
 243}
 244
 245static int
 246xfs_dir3_free_get_buf(
 247        xfs_da_args_t           *args,
 248        xfs_dir2_db_t           fbno,
 249        struct xfs_buf          **bpp)
 250{
 251        struct xfs_trans        *tp = args->trans;
 252        struct xfs_inode        *dp = args->dp;
 253        struct xfs_mount        *mp = dp->i_mount;
 254        struct xfs_buf          *bp;
 255        int                     error;
 256        struct xfs_dir3_icfree_hdr hdr;
 257
 258        error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, fbno),
 259                                   -1, &bp, XFS_DATA_FORK);
 260        if (error)
 261                return error;
 262
 263        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_FREE_BUF);
 264        bp->b_ops = &xfs_dir3_free_buf_ops;
 265
 266        /*
 267         * Initialize the new block to be empty, and remember
 268         * its first slot as our empty slot.
 269         */
 270        memset(bp->b_addr, 0, sizeof(struct xfs_dir3_free_hdr));
 271        memset(&hdr, 0, sizeof(hdr));
 272
 273        if (xfs_sb_version_hascrc(&mp->m_sb)) {
 274                struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
 275
 276                hdr.magic = XFS_DIR3_FREE_MAGIC;
 277
 278                hdr3->hdr.blkno = cpu_to_be64(bp->b_bn);
 279                hdr3->hdr.owner = cpu_to_be64(dp->i_ino);
 280                uuid_copy(&hdr3->hdr.uuid, &mp->m_sb.sb_meta_uuid);
 281        } else
 282                hdr.magic = XFS_DIR2_FREE_MAGIC;
 283        dp->d_ops->free_hdr_to_disk(bp->b_addr, &hdr);
 284        *bpp = bp;
 285        return 0;
 286}
 287
 288/*
 289 * Log entries from a freespace block.
 290 */
 291STATIC void
 292xfs_dir2_free_log_bests(
 293        struct xfs_da_args      *args,
 294        struct xfs_buf          *bp,
 295        int                     first,          /* first entry to log */
 296        int                     last)           /* last entry to log */
 297{
 298        xfs_dir2_free_t         *free;          /* freespace structure */
 299        __be16                  *bests;
 300
 301        free = bp->b_addr;
 302        bests = args->dp->d_ops->free_bests_p(free);
 303        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 304               free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 305        xfs_trans_log_buf(args->trans, bp,
 306                (uint)((char *)&bests[first] - (char *)free),
 307                (uint)((char *)&bests[last] - (char *)free +
 308                       sizeof(bests[0]) - 1));
 309}
 310
 311/*
 312 * Log header from a freespace block.
 313 */
 314static void
 315xfs_dir2_free_log_header(
 316        struct xfs_da_args      *args,
 317        struct xfs_buf          *bp)
 318{
 319#ifdef DEBUG
 320        xfs_dir2_free_t         *free;          /* freespace structure */
 321
 322        free = bp->b_addr;
 323        ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 324               free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 325#endif
 326        xfs_trans_log_buf(args->trans, bp, 0,
 327                          args->dp->d_ops->free_hdr_size - 1);
 328}
 329
 330/*
 331 * Convert a leaf-format directory to a node-format directory.
 332 * We need to change the magic number of the leaf block, and copy
 333 * the freespace table out of the leaf block into its own block.
 334 */
 335int                                             /* error */
 336xfs_dir2_leaf_to_node(
 337        xfs_da_args_t           *args,          /* operation arguments */
 338        struct xfs_buf          *lbp)           /* leaf buffer */
 339{
 340        xfs_inode_t             *dp;            /* incore directory inode */
 341        int                     error;          /* error return value */
 342        struct xfs_buf          *fbp;           /* freespace buffer */
 343        xfs_dir2_db_t           fdb;            /* freespace block number */
 344        xfs_dir2_free_t         *free;          /* freespace structure */
 345        __be16                  *from;          /* pointer to freespace entry */
 346        int                     i;              /* leaf freespace index */
 347        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 348        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
 349        int                     n;              /* count of live freespc ents */
 350        xfs_dir2_data_off_t     off;            /* freespace entry value */
 351        __be16                  *to;            /* pointer to freespace entry */
 352        xfs_trans_t             *tp;            /* transaction pointer */
 353        struct xfs_dir3_icfree_hdr freehdr;
 354
 355        trace_xfs_dir2_leaf_to_node(args);
 356
 357        dp = args->dp;
 358        tp = args->trans;
 359        /*
 360         * Add a freespace block to the directory.
 361         */
 362        if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
 363                return error;
 364        }
 365        ASSERT(fdb == xfs_dir2_byte_to_db(args->geo, XFS_DIR2_FREE_OFFSET));
 366        /*
 367         * Get the buffer for the new freespace block.
 368         */
 369        error = xfs_dir3_free_get_buf(args, fdb, &fbp);
 370        if (error)
 371                return error;
 372
 373        free = fbp->b_addr;
 374        dp->d_ops->free_hdr_from_disk(&freehdr, free);
 375        leaf = lbp->b_addr;
 376        ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 377        ASSERT(be32_to_cpu(ltp->bestcount) <=
 378                                (uint)dp->i_d.di_size / args->geo->blksize);
 379
 380        /*
 381         * Copy freespace entries from the leaf block to the new block.
 382         * Count active entries.
 383         */
 384        from = xfs_dir2_leaf_bests_p(ltp);
 385        to = dp->d_ops->free_bests_p(free);
 386        for (i = n = 0; i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
 387                if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
 388                        n++;
 389                *to = cpu_to_be16(off);
 390        }
 391
 392        /*
 393         * Now initialize the freespace block header.
 394         */
 395        freehdr.nused = n;
 396        freehdr.nvalid = be32_to_cpu(ltp->bestcount);
 397
 398        dp->d_ops->free_hdr_to_disk(fbp->b_addr, &freehdr);
 399        xfs_dir2_free_log_bests(args, fbp, 0, freehdr.nvalid - 1);
 400        xfs_dir2_free_log_header(args, fbp);
 401
 402        /*
 403         * Converting the leaf to a leafnode is just a matter of changing the
 404         * magic number and the ops. Do the change directly to the buffer as
 405         * it's less work (and less code) than decoding the header to host
 406         * format and back again.
 407         */
 408        if (leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC))
 409                leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
 410        else
 411                leaf->hdr.info.magic = cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 412        lbp->b_ops = &xfs_dir3_leafn_buf_ops;
 413        xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAFN_BUF);
 414        xfs_dir3_leaf_log_header(args, lbp);
 415        xfs_dir3_leaf_check(dp, lbp);
 416        return 0;
 417}
 418
 419/*
 420 * Add a leaf entry to a leaf block in a node-form directory.
 421 * The other work necessary is done from the caller.
 422 */
 423static int                                      /* error */
 424xfs_dir2_leafn_add(
 425        struct xfs_buf          *bp,            /* leaf buffer */
 426        xfs_da_args_t           *args,          /* operation arguments */
 427        int                     index)          /* insertion pt for new entry */
 428{
 429        int                     compact;        /* compacting stale leaves */
 430        xfs_inode_t             *dp;            /* incore directory inode */
 431        int                     highstale;      /* next stale entry */
 432        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 433        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 434        int                     lfloghigh;      /* high leaf entry logging */
 435        int                     lfloglow;       /* low leaf entry logging */
 436        int                     lowstale;       /* previous stale entry */
 437        struct xfs_dir3_icleaf_hdr leafhdr;
 438        struct xfs_dir2_leaf_entry *ents;
 439
 440        trace_xfs_dir2_leafn_add(args, index);
 441
 442        dp = args->dp;
 443        leaf = bp->b_addr;
 444        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 445        ents = dp->d_ops->leaf_ents_p(leaf);
 446
 447        /*
 448         * Quick check just to make sure we are not going to index
 449         * into other peoples memory
 450         */
 451        if (index < 0)
 452                return -EFSCORRUPTED;
 453
 454        /*
 455         * If there are already the maximum number of leaf entries in
 456         * the block, if there are no stale entries it won't fit.
 457         * Caller will do a split.  If there are stale entries we'll do
 458         * a compact.
 459         */
 460
 461        if (leafhdr.count == dp->d_ops->leaf_max_ents(args->geo)) {
 462                if (!leafhdr.stale)
 463                        return -ENOSPC;
 464                compact = leafhdr.stale > 1;
 465        } else
 466                compact = 0;
 467        ASSERT(index == 0 || be32_to_cpu(ents[index - 1].hashval) <= args->hashval);
 468        ASSERT(index == leafhdr.count ||
 469               be32_to_cpu(ents[index].hashval) >= args->hashval);
 470
 471        if (args->op_flags & XFS_DA_OP_JUSTCHECK)
 472                return 0;
 473
 474        /*
 475         * Compact out all but one stale leaf entry.  Leaves behind
 476         * the entry closest to index.
 477         */
 478        if (compact)
 479                xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 480                                         &highstale, &lfloglow, &lfloghigh);
 481        else if (leafhdr.stale) {
 482                /*
 483                 * Set impossible logging indices for this case.
 484                 */
 485                lfloglow = leafhdr.count;
 486                lfloghigh = -1;
 487        }
 488
 489        /*
 490         * Insert the new entry, log everything.
 491         */
 492        lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 493                                       highstale, &lfloglow, &lfloghigh);
 494
 495        lep->hashval = cpu_to_be32(args->hashval);
 496        lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(args->geo,
 497                                args->blkno, args->index));
 498
 499        dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
 500        xfs_dir3_leaf_log_header(args, bp);
 501        xfs_dir3_leaf_log_ents(args, bp, lfloglow, lfloghigh);
 502        xfs_dir3_leaf_check(dp, bp);
 503        return 0;
 504}
 505
 506#ifdef DEBUG
 507static void
 508xfs_dir2_free_hdr_check(
 509        struct xfs_inode *dp,
 510        struct xfs_buf  *bp,
 511        xfs_dir2_db_t   db)
 512{
 513        struct xfs_dir3_icfree_hdr hdr;
 514
 515        dp->d_ops->free_hdr_from_disk(&hdr, bp->b_addr);
 516
 517        ASSERT((hdr.firstdb %
 518                dp->d_ops->free_max_bests(dp->i_mount->m_dir_geo)) == 0);
 519        ASSERT(hdr.firstdb <= db);
 520        ASSERT(db < hdr.firstdb + hdr.nvalid);
 521}
 522#else
 523#define xfs_dir2_free_hdr_check(dp, bp, db)
 524#endif  /* DEBUG */
 525
 526/*
 527 * Return the last hash value in the leaf.
 528 * Stale entries are ok.
 529 */
 530xfs_dahash_t                                    /* hash value */
 531xfs_dir2_leaf_lasthash(
 532        struct xfs_inode *dp,
 533        struct xfs_buf  *bp,                    /* leaf buffer */
 534        int             *count)                 /* count of entries in leaf */
 535{
 536        struct xfs_dir2_leaf    *leaf = bp->b_addr;
 537        struct xfs_dir2_leaf_entry *ents;
 538        struct xfs_dir3_icleaf_hdr leafhdr;
 539
 540        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 541
 542        ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
 543               leafhdr.magic == XFS_DIR3_LEAFN_MAGIC ||
 544               leafhdr.magic == XFS_DIR2_LEAF1_MAGIC ||
 545               leafhdr.magic == XFS_DIR3_LEAF1_MAGIC);
 546
 547        if (count)
 548                *count = leafhdr.count;
 549        if (!leafhdr.count)
 550                return 0;
 551
 552        ents = dp->d_ops->leaf_ents_p(leaf);
 553        return be32_to_cpu(ents[leafhdr.count - 1].hashval);
 554}
 555
 556/*
 557 * Look up a leaf entry for space to add a name in a node-format leaf block.
 558 * The extrablk in state is a freespace block.
 559 */
 560STATIC int
 561xfs_dir2_leafn_lookup_for_addname(
 562        struct xfs_buf          *bp,            /* leaf buffer */
 563        xfs_da_args_t           *args,          /* operation arguments */
 564        int                     *indexp,        /* out: leaf entry index */
 565        xfs_da_state_t          *state)         /* state to fill in */
 566{
 567        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 568        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 569        xfs_dir2_db_t           curfdb = -1;    /* current free block number */
 570        xfs_inode_t             *dp;            /* incore directory inode */
 571        int                     error;          /* error return value */
 572        int                     fi;             /* free entry index */
 573        xfs_dir2_free_t         *free = NULL;   /* free block structure */
 574        int                     index;          /* leaf entry index */
 575        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 576        int                     length;         /* length of new data entry */
 577        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 578        xfs_mount_t             *mp;            /* filesystem mount point */
 579        xfs_dir2_db_t           newdb;          /* new data block number */
 580        xfs_dir2_db_t           newfdb;         /* new free block number */
 581        xfs_trans_t             *tp;            /* transaction pointer */
 582        struct xfs_dir2_leaf_entry *ents;
 583        struct xfs_dir3_icleaf_hdr leafhdr;
 584
 585        dp = args->dp;
 586        tp = args->trans;
 587        mp = dp->i_mount;
 588        leaf = bp->b_addr;
 589        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 590        ents = dp->d_ops->leaf_ents_p(leaf);
 591
 592        xfs_dir3_leaf_check(dp, bp);
 593        ASSERT(leafhdr.count > 0);
 594
 595        /*
 596         * Look up the hash value in the leaf entries.
 597         */
 598        index = xfs_dir2_leaf_search_hash(args, bp);
 599        /*
 600         * Do we have a buffer coming in?
 601         */
 602        if (state->extravalid) {
 603                /* If so, it's a free block buffer, get the block number. */
 604                curbp = state->extrablk.bp;
 605                curfdb = state->extrablk.blkno;
 606                free = curbp->b_addr;
 607                ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC) ||
 608                       free->hdr.magic == cpu_to_be32(XFS_DIR3_FREE_MAGIC));
 609        }
 610        length = dp->d_ops->data_entsize(args->namelen);
 611        /*
 612         * Loop over leaf entries with the right hash value.
 613         */
 614        for (lep = &ents[index];
 615             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 616             lep++, index++) {
 617                /*
 618                 * Skip stale leaf entries.
 619                 */
 620                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 621                        continue;
 622                /*
 623                 * Pull the data block number from the entry.
 624                 */
 625                newdb = xfs_dir2_dataptr_to_db(args->geo,
 626                                               be32_to_cpu(lep->address));
 627                /*
 628                 * For addname, we're looking for a place to put the new entry.
 629                 * We want to use a data block with an entry of equal
 630                 * hash value to ours if there is one with room.
 631                 *
 632                 * If this block isn't the data block we already have
 633                 * in hand, take a look at it.
 634                 */
 635                if (newdb != curdb) {
 636                        __be16 *bests;
 637
 638                        curdb = newdb;
 639                        /*
 640                         * Convert the data block to the free block
 641                         * holding its freespace information.
 642                         */
 643                        newfdb = dp->d_ops->db_to_fdb(args->geo, newdb);
 644                        /*
 645                         * If it's not the one we have in hand, read it in.
 646                         */
 647                        if (newfdb != curfdb) {
 648                                /*
 649                                 * If we had one before, drop it.
 650                                 */
 651                                if (curbp)
 652                                        xfs_trans_brelse(tp, curbp);
 653
 654                                error = xfs_dir2_free_read(tp, dp,
 655                                                xfs_dir2_db_to_da(args->geo,
 656                                                                  newfdb),
 657                                                &curbp);
 658                                if (error)
 659                                        return error;
 660                                free = curbp->b_addr;
 661
 662                                xfs_dir2_free_hdr_check(dp, curbp, curdb);
 663                        }
 664                        /*
 665                         * Get the index for our entry.
 666                         */
 667                        fi = dp->d_ops->db_to_fdindex(args->geo, curdb);
 668                        /*
 669                         * If it has room, return it.
 670                         */
 671                        bests = dp->d_ops->free_bests_p(free);
 672                        if (unlikely(bests[fi] == cpu_to_be16(NULLDATAOFF))) {
 673                                XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
 674                                                        XFS_ERRLEVEL_LOW, mp);
 675                                if (curfdb != newfdb)
 676                                        xfs_trans_brelse(tp, curbp);
 677                                return -EFSCORRUPTED;
 678                        }
 679                        curfdb = newfdb;
 680                        if (be16_to_cpu(bests[fi]) >= length)
 681                                goto out;
 682                }
 683        }
 684        /* Didn't find any space */
 685        fi = -1;
 686out:
 687        ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
 688        if (curbp) {
 689                /* Giving back a free block. */
 690                state->extravalid = 1;
 691                state->extrablk.bp = curbp;
 692                state->extrablk.index = fi;
 693                state->extrablk.blkno = curfdb;
 694
 695                /*
 696                 * Important: this magic number is not in the buffer - it's for
 697                 * buffer type information and therefore only the free/data type
 698                 * matters here, not whether CRCs are enabled or not.
 699                 */
 700                state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
 701        } else {
 702                state->extravalid = 0;
 703        }
 704        /*
 705         * Return the index, that will be the insertion point.
 706         */
 707        *indexp = index;
 708        return -ENOENT;
 709}
 710
 711/*
 712 * Look up a leaf entry in a node-format leaf block.
 713 * The extrablk in state a data block.
 714 */
 715STATIC int
 716xfs_dir2_leafn_lookup_for_entry(
 717        struct xfs_buf          *bp,            /* leaf buffer */
 718        xfs_da_args_t           *args,          /* operation arguments */
 719        int                     *indexp,        /* out: leaf entry index */
 720        xfs_da_state_t          *state)         /* state to fill in */
 721{
 722        struct xfs_buf          *curbp = NULL;  /* current data/free buffer */
 723        xfs_dir2_db_t           curdb = -1;     /* current data block number */
 724        xfs_dir2_data_entry_t   *dep;           /* data block entry */
 725        xfs_inode_t             *dp;            /* incore directory inode */
 726        int                     error;          /* error return value */
 727        int                     index;          /* leaf entry index */
 728        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 729        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
 730        xfs_mount_t             *mp;            /* filesystem mount point */
 731        xfs_dir2_db_t           newdb;          /* new data block number */
 732        xfs_trans_t             *tp;            /* transaction pointer */
 733        enum xfs_dacmp          cmp;            /* comparison result */
 734        struct xfs_dir2_leaf_entry *ents;
 735        struct xfs_dir3_icleaf_hdr leafhdr;
 736
 737        dp = args->dp;
 738        tp = args->trans;
 739        mp = dp->i_mount;
 740        leaf = bp->b_addr;
 741        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
 742        ents = dp->d_ops->leaf_ents_p(leaf);
 743
 744        xfs_dir3_leaf_check(dp, bp);
 745        ASSERT(leafhdr.count > 0);
 746
 747        /*
 748         * Look up the hash value in the leaf entries.
 749         */
 750        index = xfs_dir2_leaf_search_hash(args, bp);
 751        /*
 752         * Do we have a buffer coming in?
 753         */
 754        if (state->extravalid) {
 755                curbp = state->extrablk.bp;
 756                curdb = state->extrablk.blkno;
 757        }
 758        /*
 759         * Loop over leaf entries with the right hash value.
 760         */
 761        for (lep = &ents[index];
 762             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 763             lep++, index++) {
 764                /*
 765                 * Skip stale leaf entries.
 766                 */
 767                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 768                        continue;
 769                /*
 770                 * Pull the data block number from the entry.
 771                 */
 772                newdb = xfs_dir2_dataptr_to_db(args->geo,
 773                                               be32_to_cpu(lep->address));
 774                /*
 775                 * Not adding a new entry, so we really want to find
 776                 * the name given to us.
 777                 *
 778                 * If it's a different data block, go get it.
 779                 */
 780                if (newdb != curdb) {
 781                        /*
 782                         * If we had a block before that we aren't saving
 783                         * for a CI name, drop it
 784                         */
 785                        if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
 786                                                curdb != state->extrablk.blkno))
 787                                xfs_trans_brelse(tp, curbp);
 788                        /*
 789                         * If needing the block that is saved with a CI match,
 790                         * use it otherwise read in the new data block.
 791                         */
 792                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 793                                        newdb == state->extrablk.blkno) {
 794                                ASSERT(state->extravalid);
 795                                curbp = state->extrablk.bp;
 796                        } else {
 797                                error = xfs_dir3_data_read(tp, dp,
 798                                                xfs_dir2_db_to_da(args->geo,
 799                                                                  newdb),
 800                                                -1, &curbp);
 801                                if (error)
 802                                        return error;
 803                        }
 804                        xfs_dir3_data_check(dp, curbp);
 805                        curdb = newdb;
 806                }
 807                /*
 808                 * Point to the data entry.
 809                 */
 810                dep = (xfs_dir2_data_entry_t *)((char *)curbp->b_addr +
 811                        xfs_dir2_dataptr_to_off(args->geo,
 812                                                be32_to_cpu(lep->address)));
 813                /*
 814                 * Compare the entry and if it's an exact match, return
 815                 * EEXIST immediately. If it's the first case-insensitive
 816                 * match, store the block & inode number and continue looking.
 817                 */
 818                cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
 819                if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
 820                        /* If there is a CI match block, drop it */
 821                        if (args->cmpresult != XFS_CMP_DIFFERENT &&
 822                                                curdb != state->extrablk.blkno)
 823                                xfs_trans_brelse(tp, state->extrablk.bp);
 824                        args->cmpresult = cmp;
 825                        args->inumber = be64_to_cpu(dep->inumber);
 826                        args->filetype = dp->d_ops->data_get_ftype(dep);
 827                        *indexp = index;
 828                        state->extravalid = 1;
 829                        state->extrablk.bp = curbp;
 830                        state->extrablk.blkno = curdb;
 831                        state->extrablk.index = (int)((char *)dep -
 832                                                        (char *)curbp->b_addr);
 833                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 834                        curbp->b_ops = &xfs_dir3_data_buf_ops;
 835                        xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 836                        if (cmp == XFS_CMP_EXACT)
 837                                return -EEXIST;
 838                }
 839        }
 840        ASSERT(index == leafhdr.count || (args->op_flags & XFS_DA_OP_OKNOENT));
 841        if (curbp) {
 842                if (args->cmpresult == XFS_CMP_DIFFERENT) {
 843                        /* Giving back last used data block. */
 844                        state->extravalid = 1;
 845                        state->extrablk.bp = curbp;
 846                        state->extrablk.index = -1;
 847                        state->extrablk.blkno = curdb;
 848                        state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
 849                        curbp->b_ops = &xfs_dir3_data_buf_ops;
 850                        xfs_trans_buf_set_type(tp, curbp, XFS_BLFT_DIR_DATA_BUF);
 851                } else {
 852                        /* If the curbp is not the CI match block, drop it */
 853                        if (state->extrablk.bp != curbp)
 854                                xfs_trans_brelse(tp, curbp);
 855                }
 856        } else {
 857                state->extravalid = 0;
 858        }
 859        *indexp = index;
 860        return -ENOENT;
 861}
 862
 863/*
 864 * Look up a leaf entry in a node-format leaf block.
 865 * If this is an addname then the extrablk in state is a freespace block,
 866 * otherwise it's a data block.
 867 */
 868int
 869xfs_dir2_leafn_lookup_int(
 870        struct xfs_buf          *bp,            /* leaf buffer */
 871        xfs_da_args_t           *args,          /* operation arguments */
 872        int                     *indexp,        /* out: leaf entry index */
 873        xfs_da_state_t          *state)         /* state to fill in */
 874{
 875        if (args->op_flags & XFS_DA_OP_ADDNAME)
 876                return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
 877                                                        state);
 878        return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
 879}
 880
 881/*
 882 * Move count leaf entries from source to destination leaf.
 883 * Log entries and headers.  Stale entries are preserved.
 884 */
 885static void
 886xfs_dir3_leafn_moveents(
 887        xfs_da_args_t                   *args,  /* operation arguments */
 888        struct xfs_buf                  *bp_s,  /* source */
 889        struct xfs_dir3_icleaf_hdr      *shdr,
 890        struct xfs_dir2_leaf_entry      *sents,
 891        int                             start_s,/* source leaf index */
 892        struct xfs_buf                  *bp_d,  /* destination */
 893        struct xfs_dir3_icleaf_hdr      *dhdr,
 894        struct xfs_dir2_leaf_entry      *dents,
 895        int                             start_d,/* destination leaf index */
 896        int                             count)  /* count of leaves to copy */
 897{
 898        int                             stale;  /* count stale leaves copied */
 899
 900        trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
 901
 902        /*
 903         * Silently return if nothing to do.
 904         */
 905        if (count == 0)
 906                return;
 907
 908        /*
 909         * If the destination index is not the end of the current
 910         * destination leaf entries, open up a hole in the destination
 911         * to hold the new entries.
 912         */
 913        if (start_d < dhdr->count) {
 914                memmove(&dents[start_d + count], &dents[start_d],
 915                        (dhdr->count - start_d) * sizeof(xfs_dir2_leaf_entry_t));
 916                xfs_dir3_leaf_log_ents(args, bp_d, start_d + count,
 917                                       count + dhdr->count - 1);
 918        }
 919        /*
 920         * If the source has stale leaves, count the ones in the copy range
 921         * so we can update the header correctly.
 922         */
 923        if (shdr->stale) {
 924                int     i;                      /* temp leaf index */
 925
 926                for (i = start_s, stale = 0; i < start_s + count; i++) {
 927                        if (sents[i].address ==
 928                                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 929                                stale++;
 930                }
 931        } else
 932                stale = 0;
 933        /*
 934         * Copy the leaf entries from source to destination.
 935         */
 936        memcpy(&dents[start_d], &sents[start_s],
 937                count * sizeof(xfs_dir2_leaf_entry_t));
 938        xfs_dir3_leaf_log_ents(args, bp_d, start_d, start_d + count - 1);
 939
 940        /*
 941         * If there are source entries after the ones we copied,
 942         * delete the ones we copied by sliding the next ones down.
 943         */
 944        if (start_s + count < shdr->count) {
 945                memmove(&sents[start_s], &sents[start_s + count],
 946                        count * sizeof(xfs_dir2_leaf_entry_t));
 947                xfs_dir3_leaf_log_ents(args, bp_s, start_s, start_s + count - 1);
 948        }
 949
 950        /*
 951         * Update the headers and log them.
 952         */
 953        shdr->count -= count;
 954        shdr->stale -= stale;
 955        dhdr->count += count;
 956        dhdr->stale += stale;
 957}
 958
 959/*
 960 * Determine the sort order of two leaf blocks.
 961 * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
 962 */
 963int                                             /* sort order */
 964xfs_dir2_leafn_order(
 965        struct xfs_inode        *dp,
 966        struct xfs_buf          *leaf1_bp,              /* leaf1 buffer */
 967        struct xfs_buf          *leaf2_bp)              /* leaf2 buffer */
 968{
 969        struct xfs_dir2_leaf    *leaf1 = leaf1_bp->b_addr;
 970        struct xfs_dir2_leaf    *leaf2 = leaf2_bp->b_addr;
 971        struct xfs_dir2_leaf_entry *ents1;
 972        struct xfs_dir2_leaf_entry *ents2;
 973        struct xfs_dir3_icleaf_hdr hdr1;
 974        struct xfs_dir3_icleaf_hdr hdr2;
 975
 976        dp->d_ops->leaf_hdr_from_disk(&hdr1, leaf1);
 977        dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf2);
 978        ents1 = dp->d_ops->leaf_ents_p(leaf1);
 979        ents2 = dp->d_ops->leaf_ents_p(leaf2);
 980
 981        if (hdr1.count > 0 && hdr2.count > 0 &&
 982            (be32_to_cpu(ents2[0].hashval) < be32_to_cpu(ents1[0].hashval) ||
 983             be32_to_cpu(ents2[hdr2.count - 1].hashval) <
 984                                be32_to_cpu(ents1[hdr1.count - 1].hashval)))
 985                return 1;
 986        return 0;
 987}
 988
 989/*
 990 * Rebalance leaf entries between two leaf blocks.
 991 * This is actually only called when the second block is new,
 992 * though the code deals with the general case.
 993 * A new entry will be inserted in one of the blocks, and that
 994 * entry is taken into account when balancing.
 995 */
 996static void
 997xfs_dir2_leafn_rebalance(
 998        xfs_da_state_t          *state,         /* btree cursor */
 999        xfs_da_state_blk_t      *blk1,          /* first btree block */
1000        xfs_da_state_blk_t      *blk2)          /* second btree block */
1001{
1002        xfs_da_args_t           *args;          /* operation arguments */
1003        int                     count;          /* count (& direction) leaves */
1004        int                     isleft;         /* new goes in left leaf */
1005        xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
1006        xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
1007        int                     mid;            /* midpoint leaf index */
1008#if defined(DEBUG) || defined(XFS_WARN)
1009        int                     oldstale;       /* old count of stale leaves */
1010#endif
1011        int                     oldsum;         /* old total leaf count */
1012        int                     swap;           /* swapped leaf blocks */
1013        struct xfs_dir2_leaf_entry *ents1;
1014        struct xfs_dir2_leaf_entry *ents2;
1015        struct xfs_dir3_icleaf_hdr hdr1;
1016        struct xfs_dir3_icleaf_hdr hdr2;
1017        struct xfs_inode        *dp = state->args->dp;
1018
1019        args = state->args;
1020        /*
1021         * If the block order is wrong, swap the arguments.
1022         */
1023        if ((swap = xfs_dir2_leafn_order(dp, blk1->bp, blk2->bp))) {
1024                xfs_da_state_blk_t      *tmp;   /* temp for block swap */
1025
1026                tmp = blk1;
1027                blk1 = blk2;
1028                blk2 = tmp;
1029        }
1030        leaf1 = blk1->bp->b_addr;
1031        leaf2 = blk2->bp->b_addr;
1032        dp->d_ops->leaf_hdr_from_disk(&hdr1, leaf1);
1033        dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf2);
1034        ents1 = dp->d_ops->leaf_ents_p(leaf1);
1035        ents2 = dp->d_ops->leaf_ents_p(leaf2);
1036
1037        oldsum = hdr1.count + hdr2.count;
1038#if defined(DEBUG) || defined(XFS_WARN)
1039        oldstale = hdr1.stale + hdr2.stale;
1040#endif
1041        mid = oldsum >> 1;
1042
1043        /*
1044         * If the old leaf count was odd then the new one will be even,
1045         * so we need to divide the new count evenly.
1046         */
1047        if (oldsum & 1) {
1048                xfs_dahash_t    midhash;        /* middle entry hash value */
1049
1050                if (mid >= hdr1.count)
1051                        midhash = be32_to_cpu(ents2[mid - hdr1.count].hashval);
1052                else
1053                        midhash = be32_to_cpu(ents1[mid].hashval);
1054                isleft = args->hashval <= midhash;
1055        }
1056        /*
1057         * If the old count is even then the new count is odd, so there's
1058         * no preferred side for the new entry.
1059         * Pick the left one.
1060         */
1061        else
1062                isleft = 1;
1063        /*
1064         * Calculate moved entry count.  Positive means left-to-right,
1065         * negative means right-to-left.  Then move the entries.
1066         */
1067        count = hdr1.count - mid + (isleft == 0);
1068        if (count > 0)
1069                xfs_dir3_leafn_moveents(args, blk1->bp, &hdr1, ents1,
1070                                        hdr1.count - count, blk2->bp,
1071                                        &hdr2, ents2, 0, count);
1072        else if (count < 0)
1073                xfs_dir3_leafn_moveents(args, blk2->bp, &hdr2, ents2, 0,
1074                                        blk1->bp, &hdr1, ents1,
1075                                        hdr1.count, count);
1076
1077        ASSERT(hdr1.count + hdr2.count == oldsum);
1078        ASSERT(hdr1.stale + hdr2.stale == oldstale);
1079
1080        /* log the changes made when moving the entries */
1081        dp->d_ops->leaf_hdr_to_disk(leaf1, &hdr1);
1082        dp->d_ops->leaf_hdr_to_disk(leaf2, &hdr2);
1083        xfs_dir3_leaf_log_header(args, blk1->bp);
1084        xfs_dir3_leaf_log_header(args, blk2->bp);
1085
1086        xfs_dir3_leaf_check(dp, blk1->bp);
1087        xfs_dir3_leaf_check(dp, blk2->bp);
1088
1089        /*
1090         * Mark whether we're inserting into the old or new leaf.
1091         */
1092        if (hdr1.count < hdr2.count)
1093                state->inleaf = swap;
1094        else if (hdr1.count > hdr2.count)
1095                state->inleaf = !swap;
1096        else
1097                state->inleaf = swap ^ (blk1->index <= hdr1.count);
1098        /*
1099         * Adjust the expected index for insertion.
1100         */
1101        if (!state->inleaf)
1102                blk2->index = blk1->index - hdr1.count;
1103
1104        /*
1105         * Finally sanity check just to make sure we are not returning a
1106         * negative index
1107         */
1108        if (blk2->index < 0) {
1109                state->inleaf = 1;
1110                blk2->index = 0;
1111                xfs_alert(dp->i_mount,
1112        "%s: picked the wrong leaf? reverting original leaf: blk1->index %d",
1113                        __func__, blk1->index);
1114        }
1115}
1116
1117static int
1118xfs_dir3_data_block_free(
1119        xfs_da_args_t           *args,
1120        struct xfs_dir2_data_hdr *hdr,
1121        struct xfs_dir2_free    *free,
1122        xfs_dir2_db_t           fdb,
1123        int                     findex,
1124        struct xfs_buf          *fbp,
1125        int                     longest)
1126{
1127        int                     logfree = 0;
1128        __be16                  *bests;
1129        struct xfs_dir3_icfree_hdr freehdr;
1130        struct xfs_inode        *dp = args->dp;
1131
1132        dp->d_ops->free_hdr_from_disk(&freehdr, free);
1133        bests = dp->d_ops->free_bests_p(free);
1134        if (hdr) {
1135                /*
1136                 * Data block is not empty, just set the free entry to the new
1137                 * value.
1138                 */
1139                bests[findex] = cpu_to_be16(longest);
1140                xfs_dir2_free_log_bests(args, fbp, findex, findex);
1141                return 0;
1142        }
1143
1144        /* One less used entry in the free table. */
1145        freehdr.nused--;
1146
1147        /*
1148         * If this was the last entry in the table, we can trim the table size
1149         * back.  There might be other entries at the end referring to
1150         * non-existent data blocks, get those too.
1151         */
1152        if (findex == freehdr.nvalid - 1) {
1153                int     i;              /* free entry index */
1154
1155                for (i = findex - 1; i >= 0; i--) {
1156                        if (bests[i] != cpu_to_be16(NULLDATAOFF))
1157                                break;
1158                }
1159                freehdr.nvalid = i + 1;
1160                logfree = 0;
1161        } else {
1162                /* Not the last entry, just punch it out.  */
1163                bests[findex] = cpu_to_be16(NULLDATAOFF);
1164                logfree = 1;
1165        }
1166
1167        dp->d_ops->free_hdr_to_disk(free, &freehdr);
1168        xfs_dir2_free_log_header(args, fbp);
1169
1170        /*
1171         * If there are no useful entries left in the block, get rid of the
1172         * block if we can.
1173         */
1174        if (!freehdr.nused) {
1175                int error;
1176
1177                error = xfs_dir2_shrink_inode(args, fdb, fbp);
1178                if (error == 0) {
1179                        fbp = NULL;
1180                        logfree = 0;
1181                } else if (error != -ENOSPC || args->total != 0)
1182                        return error;
1183                /*
1184                 * It's possible to get ENOSPC if there is no
1185                 * space reservation.  In this case some one
1186                 * else will eventually get rid of this block.
1187                 */
1188        }
1189
1190        /* Log the free entry that changed, unless we got rid of it.  */
1191        if (logfree)
1192                xfs_dir2_free_log_bests(args, fbp, findex, findex);
1193        return 0;
1194}
1195
1196/*
1197 * Remove an entry from a node directory.
1198 * This removes the leaf entry and the data entry,
1199 * and updates the free block if necessary.
1200 */
1201static int                                      /* error */
1202xfs_dir2_leafn_remove(
1203        xfs_da_args_t           *args,          /* operation arguments */
1204        struct xfs_buf          *bp,            /* leaf buffer */
1205        int                     index,          /* leaf entry index */
1206        xfs_da_state_blk_t      *dblk,          /* data block */
1207        int                     *rval)          /* resulting block needs join */
1208{
1209        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1210        xfs_dir2_db_t           db;             /* data block number */
1211        struct xfs_buf          *dbp;           /* data block buffer */
1212        xfs_dir2_data_entry_t   *dep;           /* data block entry */
1213        xfs_inode_t             *dp;            /* incore directory inode */
1214        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1215        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1216        int                     longest;        /* longest data free entry */
1217        int                     off;            /* data block entry offset */
1218        int                     needlog;        /* need to log data header */
1219        int                     needscan;       /* need to rescan data frees */
1220        xfs_trans_t             *tp;            /* transaction pointer */
1221        struct xfs_dir2_data_free *bf;          /* bestfree table */
1222        struct xfs_dir3_icleaf_hdr leafhdr;
1223        struct xfs_dir2_leaf_entry *ents;
1224
1225        trace_xfs_dir2_leafn_remove(args, index);
1226
1227        dp = args->dp;
1228        tp = args->trans;
1229        leaf = bp->b_addr;
1230        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1231        ents = dp->d_ops->leaf_ents_p(leaf);
1232
1233        /*
1234         * Point to the entry we're removing.
1235         */
1236        lep = &ents[index];
1237
1238        /*
1239         * Extract the data block and offset from the entry.
1240         */
1241        db = xfs_dir2_dataptr_to_db(args->geo, be32_to_cpu(lep->address));
1242        ASSERT(dblk->blkno == db);
1243        off = xfs_dir2_dataptr_to_off(args->geo, be32_to_cpu(lep->address));
1244        ASSERT(dblk->index == off);
1245
1246        /*
1247         * Kill the leaf entry by marking it stale.
1248         * Log the leaf block changes.
1249         */
1250        leafhdr.stale++;
1251        dp->d_ops->leaf_hdr_to_disk(leaf, &leafhdr);
1252        xfs_dir3_leaf_log_header(args, bp);
1253
1254        lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1255        xfs_dir3_leaf_log_ents(args, bp, index, index);
1256
1257        /*
1258         * Make the data entry free.  Keep track of the longest freespace
1259         * in the data block in case it changes.
1260         */
1261        dbp = dblk->bp;
1262        hdr = dbp->b_addr;
1263        dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
1264        bf = dp->d_ops->data_bestfree_p(hdr);
1265        longest = be16_to_cpu(bf[0].length);
1266        needlog = needscan = 0;
1267        xfs_dir2_data_make_free(args, dbp, off,
1268                dp->d_ops->data_entsize(dep->namelen), &needlog, &needscan);
1269        /*
1270         * Rescan the data block freespaces for bestfree.
1271         * Log the data block header if needed.
1272         */
1273        if (needscan)
1274                xfs_dir2_data_freescan(dp, hdr, &needlog);
1275        if (needlog)
1276                xfs_dir2_data_log_header(args, dbp);
1277        xfs_dir3_data_check(dp, dbp);
1278        /*
1279         * If the longest data block freespace changes, need to update
1280         * the corresponding freeblock entry.
1281         */
1282        if (longest < be16_to_cpu(bf[0].length)) {
1283                int             error;          /* error return value */
1284                struct xfs_buf  *fbp;           /* freeblock buffer */
1285                xfs_dir2_db_t   fdb;            /* freeblock block number */
1286                int             findex;         /* index in freeblock entries */
1287                xfs_dir2_free_t *free;          /* freeblock structure */
1288
1289                /*
1290                 * Convert the data block number to a free block,
1291                 * read in the free block.
1292                 */
1293                fdb = dp->d_ops->db_to_fdb(args->geo, db);
1294                error = xfs_dir2_free_read(tp, dp,
1295                                           xfs_dir2_db_to_da(args->geo, fdb),
1296                                           &fbp);
1297                if (error)
1298                        return error;
1299                free = fbp->b_addr;
1300#ifdef DEBUG
1301        {
1302                struct xfs_dir3_icfree_hdr freehdr;
1303                dp->d_ops->free_hdr_from_disk(&freehdr, free);
1304                ASSERT(freehdr.firstdb == dp->d_ops->free_max_bests(args->geo) *
1305                        (fdb - xfs_dir2_byte_to_db(args->geo,
1306                                                   XFS_DIR2_FREE_OFFSET)));
1307        }
1308#endif
1309                /*
1310                 * Calculate which entry we need to fix.
1311                 */
1312                findex = dp->d_ops->db_to_fdindex(args->geo, db);
1313                longest = be16_to_cpu(bf[0].length);
1314                /*
1315                 * If the data block is now empty we can get rid of it
1316                 * (usually).
1317                 */
1318                if (longest == args->geo->blksize -
1319                               dp->d_ops->data_entry_offset) {
1320                        /*
1321                         * Try to punch out the data block.
1322                         */
1323                        error = xfs_dir2_shrink_inode(args, db, dbp);
1324                        if (error == 0) {
1325                                dblk->bp = NULL;
1326                                hdr = NULL;
1327                        }
1328                        /*
1329                         * We can get ENOSPC if there's no space reservation.
1330                         * In this case just drop the buffer and some one else
1331                         * will eventually get rid of the empty block.
1332                         */
1333                        else if (!(error == -ENOSPC && args->total == 0))
1334                                return error;
1335                }
1336                /*
1337                 * If we got rid of the data block, we can eliminate that entry
1338                 * in the free block.
1339                 */
1340                error = xfs_dir3_data_block_free(args, hdr, free,
1341                                                 fdb, findex, fbp, longest);
1342                if (error)
1343                        return error;
1344        }
1345
1346        xfs_dir3_leaf_check(dp, bp);
1347        /*
1348         * Return indication of whether this leaf block is empty enough
1349         * to justify trying to join it with a neighbor.
1350         */
1351        *rval = (dp->d_ops->leaf_hdr_size +
1352                 (uint)sizeof(ents[0]) * (leafhdr.count - leafhdr.stale)) <
1353                args->geo->magicpct;
1354        return 0;
1355}
1356
1357/*
1358 * Split the leaf entries in the old block into old and new blocks.
1359 */
1360int                                             /* error */
1361xfs_dir2_leafn_split(
1362        xfs_da_state_t          *state,         /* btree cursor */
1363        xfs_da_state_blk_t      *oldblk,        /* original block */
1364        xfs_da_state_blk_t      *newblk)        /* newly created block */
1365{
1366        xfs_da_args_t           *args;          /* operation arguments */
1367        xfs_dablk_t             blkno;          /* new leaf block number */
1368        int                     error;          /* error return value */
1369        struct xfs_inode        *dp;
1370
1371        /*
1372         * Allocate space for a new leaf node.
1373         */
1374        args = state->args;
1375        dp = args->dp;
1376        ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1377        error = xfs_da_grow_inode(args, &blkno);
1378        if (error) {
1379                return error;
1380        }
1381        /*
1382         * Initialize the new leaf block.
1383         */
1384        error = xfs_dir3_leaf_get_buf(args, xfs_dir2_da_to_db(args->geo, blkno),
1385                                      &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1386        if (error)
1387                return error;
1388
1389        newblk->blkno = blkno;
1390        newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1391        /*
1392         * Rebalance the entries across the two leaves, link the new
1393         * block into the leaves.
1394         */
1395        xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1396        error = xfs_da3_blk_link(state, oldblk, newblk);
1397        if (error) {
1398                return error;
1399        }
1400        /*
1401         * Insert the new entry in the correct block.
1402         */
1403        if (state->inleaf)
1404                error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1405        else
1406                error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1407        /*
1408         * Update last hashval in each block since we added the name.
1409         */
1410        oldblk->hashval = xfs_dir2_leaf_lasthash(dp, oldblk->bp, NULL);
1411        newblk->hashval = xfs_dir2_leaf_lasthash(dp, newblk->bp, NULL);
1412        xfs_dir3_leaf_check(dp, oldblk->bp);
1413        xfs_dir3_leaf_check(dp, newblk->bp);
1414        return error;
1415}
1416
1417/*
1418 * Check a leaf block and its neighbors to see if the block should be
1419 * collapsed into one or the other neighbor.  Always keep the block
1420 * with the smaller block number.
1421 * If the current block is over 50% full, don't try to join it, return 0.
1422 * If the block is empty, fill in the state structure and return 2.
1423 * If it can be collapsed, fill in the state structure and return 1.
1424 * If nothing can be done, return 0.
1425 */
1426int                                             /* error */
1427xfs_dir2_leafn_toosmall(
1428        xfs_da_state_t          *state,         /* btree cursor */
1429        int                     *action)        /* resulting action to take */
1430{
1431        xfs_da_state_blk_t      *blk;           /* leaf block */
1432        xfs_dablk_t             blkno;          /* leaf block number */
1433        struct xfs_buf          *bp;            /* leaf buffer */
1434        int                     bytes;          /* bytes in use */
1435        int                     count;          /* leaf live entry count */
1436        int                     error;          /* error return value */
1437        int                     forward;        /* sibling block direction */
1438        int                     i;              /* sibling counter */
1439        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1440        int                     rval;           /* result from path_shift */
1441        struct xfs_dir3_icleaf_hdr leafhdr;
1442        struct xfs_dir2_leaf_entry *ents;
1443        struct xfs_inode        *dp = state->args->dp;
1444
1445        /*
1446         * Check for the degenerate case of the block being over 50% full.
1447         * If so, it's not worth even looking to see if we might be able
1448         * to coalesce with a sibling.
1449         */
1450        blk = &state->path.blk[state->path.active - 1];
1451        leaf = blk->bp->b_addr;
1452        dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
1453        ents = dp->d_ops->leaf_ents_p(leaf);
1454        xfs_dir3_leaf_check(dp, blk->bp);
1455
1456        count = leafhdr.count - leafhdr.stale;
1457        bytes = dp->d_ops->leaf_hdr_size + count * sizeof(ents[0]);
1458        if (bytes > (state->args->geo->blksize >> 1)) {
1459                /*
1460                 * Blk over 50%, don't try to join.
1461                 */
1462                *action = 0;
1463                return 0;
1464        }
1465        /*
1466         * Check for the degenerate case of the block being empty.
1467         * If the block is empty, we'll simply delete it, no need to
1468         * coalesce it with a sibling block.  We choose (arbitrarily)
1469         * to merge with the forward block unless it is NULL.
1470         */
1471        if (count == 0) {
1472                /*
1473                 * Make altpath point to the block we want to keep and
1474                 * path point to the block we want to drop (this one).
1475                 */
1476                forward = (leafhdr.forw != 0);
1477                memcpy(&state->altpath, &state->path, sizeof(state->path));
1478                error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1479                        &rval);
1480                if (error)
1481                        return error;
1482                *action = rval ? 2 : 0;
1483                return 0;
1484        }
1485        /*
1486         * Examine each sibling block to see if we can coalesce with
1487         * at least 25% free space to spare.  We need to figure out
1488         * whether to merge with the forward or the backward block.
1489         * We prefer coalescing with the lower numbered sibling so as
1490         * to shrink a directory over time.
1491         */
1492        forward = leafhdr.forw < leafhdr.back;
1493        for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1494                struct xfs_dir3_icleaf_hdr hdr2;
1495
1496                blkno = forward ? leafhdr.forw : leafhdr.back;
1497                if (blkno == 0)
1498                        continue;
1499                /*
1500                 * Read the sibling leaf block.
1501                 */
1502                error = xfs_dir3_leafn_read(state->args->trans, dp,
1503                                            blkno, -1, &bp);
1504                if (error)
1505                        return error;
1506
1507                /*
1508                 * Count bytes in the two blocks combined.
1509                 */
1510                count = leafhdr.count - leafhdr.stale;
1511                bytes = state->args->geo->blksize -
1512                        (state->args->geo->blksize >> 2);
1513
1514                leaf = bp->b_addr;
1515                dp->d_ops->leaf_hdr_from_disk(&hdr2, leaf);
1516                ents = dp->d_ops->leaf_ents_p(leaf);
1517                count += hdr2.count - hdr2.stale;
1518                bytes -= count * sizeof(ents[0]);
1519
1520                /*
1521                 * Fits with at least 25% to spare.
1522                 */
1523                if (bytes >= 0)
1524                        break;
1525                xfs_trans_brelse(state->args->trans, bp);
1526        }
1527        /*
1528         * Didn't like either block, give up.
1529         */
1530        if (i >= 2) {
1531                *action = 0;
1532                return 0;
1533        }
1534
1535        /*
1536         * Make altpath point to the block we want to keep (the lower
1537         * numbered block) and path point to the block we want to drop.
1538         */
1539        memcpy(&state->altpath, &state->path, sizeof(state->path));
1540        if (blkno < blk->blkno)
1541                error = xfs_da3_path_shift(state, &state->altpath, forward, 0,
1542                        &rval);
1543        else
1544                error = xfs_da3_path_shift(state, &state->path, forward, 0,
1545                        &rval);
1546        if (error) {
1547                return error;
1548        }
1549        *action = rval ? 0 : 1;
1550        return 0;
1551}
1552
1553/*
1554 * Move all the leaf entries from drop_blk to save_blk.
1555 * This is done as part of a join operation.
1556 */
1557void
1558xfs_dir2_leafn_unbalance(
1559        xfs_da_state_t          *state,         /* cursor */
1560        xfs_da_state_blk_t      *drop_blk,      /* dead block */
1561        xfs_da_state_blk_t      *save_blk)      /* surviving block */
1562{
1563        xfs_da_args_t           *args;          /* operation arguments */
1564        xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1565        xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1566        struct xfs_dir3_icleaf_hdr savehdr;
1567        struct xfs_dir3_icleaf_hdr drophdr;
1568        struct xfs_dir2_leaf_entry *sents;
1569        struct xfs_dir2_leaf_entry *dents;
1570        struct xfs_inode        *dp = state->args->dp;
1571
1572        args = state->args;
1573        ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1574        ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1575        drop_leaf = drop_blk->bp->b_addr;
1576        save_leaf = save_blk->bp->b_addr;
1577
1578        dp->d_ops->leaf_hdr_from_disk(&savehdr, save_leaf);
1579        dp->d_ops->leaf_hdr_from_disk(&drophdr, drop_leaf);
1580        sents = dp->d_ops->leaf_ents_p(save_leaf);
1581        dents = dp->d_ops->leaf_ents_p(drop_leaf);
1582
1583        /*
1584         * If there are any stale leaf entries, take this opportunity
1585         * to purge them.
1586         */
1587        if (drophdr.stale)
1588                xfs_dir3_leaf_compact(args, &drophdr, drop_blk->bp);
1589        if (savehdr.stale)
1590                xfs_dir3_leaf_compact(args, &savehdr, save_blk->bp);
1591
1592        /*
1593         * Move the entries from drop to the appropriate end of save.
1594         */
1595        drop_blk->hashval = be32_to_cpu(dents[drophdr.count - 1].hashval);
1596        if (xfs_dir2_leafn_order(dp, save_blk->bp, drop_blk->bp))
1597                xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1598                                        save_blk->bp, &savehdr, sents, 0,
1599                                        drophdr.count);
1600        else
1601                xfs_dir3_leafn_moveents(args, drop_blk->bp, &drophdr, dents, 0,
1602                                        save_blk->bp, &savehdr, sents,
1603                                        savehdr.count, drophdr.count);
1604        save_blk->hashval = be32_to_cpu(sents[savehdr.count - 1].hashval);
1605
1606        /* log the changes made when moving the entries */
1607        dp->d_ops->leaf_hdr_to_disk(save_leaf, &savehdr);
1608        dp->d_ops->leaf_hdr_to_disk(drop_leaf, &drophdr);
1609        xfs_dir3_leaf_log_header(args, save_blk->bp);
1610        xfs_dir3_leaf_log_header(args, drop_blk->bp);
1611
1612        xfs_dir3_leaf_check(dp, save_blk->bp);
1613        xfs_dir3_leaf_check(dp, drop_blk->bp);
1614}
1615
1616/*
1617 * Top-level node form directory addname routine.
1618 */
1619int                                             /* error */
1620xfs_dir2_node_addname(
1621        xfs_da_args_t           *args)          /* operation arguments */
1622{
1623        xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1624        int                     error;          /* error return value */
1625        int                     rval;           /* sub-return value */
1626        xfs_da_state_t          *state;         /* btree cursor */
1627
1628        trace_xfs_dir2_node_addname(args);
1629
1630        /*
1631         * Allocate and initialize the state (btree cursor).
1632         */
1633        state = xfs_da_state_alloc();
1634        state->args = args;
1635        state->mp = args->dp->i_mount;
1636        /*
1637         * Look up the name.  We're not supposed to find it, but
1638         * this gives us the insertion point.
1639         */
1640        error = xfs_da3_node_lookup_int(state, &rval);
1641        if (error)
1642                rval = error;
1643        if (rval != -ENOENT) {
1644                goto done;
1645        }
1646        /*
1647         * Add the data entry to a data block.
1648         * Extravalid is set to a freeblock found by lookup.
1649         */
1650        rval = xfs_dir2_node_addname_int(args,
1651                state->extravalid ? &state->extrablk : NULL);
1652        if (rval) {
1653                goto done;
1654        }
1655        blk = &state->path.blk[state->path.active - 1];
1656        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1657        /*
1658         * Add the new leaf entry.
1659         */
1660        rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1661        if (rval == 0) {
1662                /*
1663                 * It worked, fix the hash values up the btree.
1664                 */
1665                if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1666                        xfs_da3_fixhashpath(state, &state->path);
1667        } else {
1668                /*
1669                 * It didn't work, we need to split the leaf block.
1670                 */
1671                if (args->total == 0) {
1672                        ASSERT(rval == -ENOSPC);
1673                        goto done;
1674                }
1675                /*
1676                 * Split the leaf block and insert the new entry.
1677                 */
1678                rval = xfs_da3_split(state);
1679        }
1680done:
1681        xfs_da_state_free(state);
1682        return rval;
1683}
1684
1685/*
1686 * Add the data entry for a node-format directory name addition.
1687 * The leaf entry is added in xfs_dir2_leafn_add.
1688 * We may enter with a freespace block that the lookup found.
1689 */
1690static int                                      /* error */
1691xfs_dir2_node_addname_int(
1692        xfs_da_args_t           *args,          /* operation arguments */
1693        xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1694{
1695        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1696        xfs_dir2_db_t           dbno;           /* data block number */
1697        struct xfs_buf          *dbp;           /* data block buffer */
1698        xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1699        xfs_inode_t             *dp;            /* incore directory inode */
1700        xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1701        int                     error;          /* error return value */
1702        xfs_dir2_db_t           fbno;           /* freespace block number */
1703        struct xfs_buf          *fbp;           /* freespace buffer */
1704        int                     findex;         /* freespace entry index */
1705        xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1706        xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1707        xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1708        int                     length;         /* length of the new entry */
1709        int                     logfree;        /* need to log free entry */
1710        xfs_mount_t             *mp;            /* filesystem mount point */
1711        int                     needlog;        /* need to log data header */
1712        int                     needscan;       /* need to rescan data frees */
1713        __be16                  *tagp;          /* data entry tag pointer */
1714        xfs_trans_t             *tp;            /* transaction pointer */
1715        __be16                  *bests;
1716        struct xfs_dir3_icfree_hdr freehdr;
1717        struct xfs_dir2_data_free *bf;
1718
1719        dp = args->dp;
1720        mp = dp->i_mount;
1721        tp = args->trans;
1722        length = dp->d_ops->data_entsize(args->namelen);
1723        /*
1724         * If we came in with a freespace block that means that lookup
1725         * found an entry with our hash value.  This is the freespace
1726         * block for that data entry.
1727         */
1728        if (fblk) {
1729                fbp = fblk->bp;
1730                /*
1731                 * Remember initial freespace block number.
1732                 */
1733                ifbno = fblk->blkno;
1734                free = fbp->b_addr;
1735                findex = fblk->index;
1736                bests = dp->d_ops->free_bests_p(free);
1737                dp->d_ops->free_hdr_from_disk(&freehdr, free);
1738
1739                /*
1740                 * This means the free entry showed that the data block had
1741                 * space for our entry, so we remembered it.
1742                 * Use that data block.
1743                 */
1744                if (findex >= 0) {
1745                        ASSERT(findex < freehdr.nvalid);
1746                        ASSERT(be16_to_cpu(bests[findex]) != NULLDATAOFF);
1747                        ASSERT(be16_to_cpu(bests[findex]) >= length);
1748                        dbno = freehdr.firstdb + findex;
1749                } else {
1750                        /*
1751                         * The data block looked at didn't have enough room.
1752                         * We'll start at the beginning of the freespace entries.
1753                         */
1754                        dbno = -1;
1755                        findex = 0;
1756                }
1757        } else {
1758                /*
1759                 * Didn't come in with a freespace block, so no data block.
1760                 */
1761                ifbno = dbno = -1;
1762                fbp = NULL;
1763                findex = 0;
1764        }
1765
1766        /*
1767         * If we don't have a data block yet, we're going to scan the
1768         * freespace blocks looking for one.  Figure out what the
1769         * highest freespace block number is.
1770         */
1771        if (dbno == -1) {
1772                xfs_fileoff_t   fo;             /* freespace block number */
1773
1774                if ((error = xfs_bmap_last_offset(dp, &fo, XFS_DATA_FORK)))
1775                        return error;
1776                lastfbno = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)fo);
1777                fbno = ifbno;
1778        }
1779        /*
1780         * While we haven't identified a data block, search the freeblock
1781         * data for a good data block.  If we find a null freeblock entry,
1782         * indicating a hole in the data blocks, remember that.
1783         */
1784        while (dbno == -1) {
1785                /*
1786                 * If we don't have a freeblock in hand, get the next one.
1787                 */
1788                if (fbp == NULL) {
1789                        /*
1790                         * Happens the first time through unless lookup gave
1791                         * us a freespace block to start with.
1792                         */
1793                        if (++fbno == 0)
1794                                fbno = xfs_dir2_byte_to_db(args->geo,
1795                                                        XFS_DIR2_FREE_OFFSET);
1796                        /*
1797                         * If it's ifbno we already looked at it.
1798                         */
1799                        if (fbno == ifbno)
1800                                fbno++;
1801                        /*
1802                         * If it's off the end we're done.
1803                         */
1804                        if (fbno >= lastfbno)
1805                                break;
1806                        /*
1807                         * Read the block.  There can be holes in the
1808                         * freespace blocks, so this might not succeed.
1809                         * This should be really rare, so there's no reason
1810                         * to avoid it.
1811                         */
1812                        error = xfs_dir2_free_try_read(tp, dp,
1813                                        xfs_dir2_db_to_da(args->geo, fbno),
1814                                        &fbp);
1815                        if (error)
1816                                return error;
1817                        if (!fbp)
1818                                continue;
1819                        free = fbp->b_addr;
1820                        findex = 0;
1821                }
1822                /*
1823                 * Look at the current free entry.  Is it good enough?
1824                 *
1825                 * The bests initialisation should be where the bufer is read in
1826                 * the above branch. But gcc is too stupid to realise that bests
1827                 * and the freehdr are actually initialised if they are placed
1828                 * there, so we have to do it here to avoid warnings. Blech.
1829                 */
1830                bests = dp->d_ops->free_bests_p(free);
1831                dp->d_ops->free_hdr_from_disk(&freehdr, free);
1832                if (be16_to_cpu(bests[findex]) != NULLDATAOFF &&
1833                    be16_to_cpu(bests[findex]) >= length)
1834                        dbno = freehdr.firstdb + findex;
1835                else {
1836                        /*
1837                         * Are we done with the freeblock?
1838                         */
1839                        if (++findex == freehdr.nvalid) {
1840                                /*
1841                                 * Drop the block.
1842                                 */
1843                                xfs_trans_brelse(tp, fbp);
1844                                fbp = NULL;
1845                                if (fblk && fblk->bp)
1846                                        fblk->bp = NULL;
1847                        }
1848                }
1849        }
1850        /*
1851         * If we don't have a data block, we need to allocate one and make
1852         * the freespace entries refer to it.
1853         */
1854        if (unlikely(dbno == -1)) {
1855                /*
1856                 * Not allowed to allocate, return failure.
1857                 */
1858                if ((args->op_flags & XFS_DA_OP_JUSTCHECK) || args->total == 0)
1859                        return -ENOSPC;
1860
1861                /*
1862                 * Allocate and initialize the new data block.
1863                 */
1864                if (unlikely((error = xfs_dir2_grow_inode(args,
1865                                                         XFS_DIR2_DATA_SPACE,
1866                                                         &dbno)) ||
1867                    (error = xfs_dir3_data_init(args, dbno, &dbp))))
1868                        return error;
1869
1870                /*
1871                 * If (somehow) we have a freespace block, get rid of it.
1872                 */
1873                if (fbp)
1874                        xfs_trans_brelse(tp, fbp);
1875                if (fblk && fblk->bp)
1876                        fblk->bp = NULL;
1877
1878                /*
1879                 * Get the freespace block corresponding to the data block
1880                 * that was just allocated.
1881                 */
1882                fbno = dp->d_ops->db_to_fdb(args->geo, dbno);
1883                error = xfs_dir2_free_try_read(tp, dp,
1884                                       xfs_dir2_db_to_da(args->geo, fbno),
1885                                       &fbp);
1886                if (error)
1887                        return error;
1888
1889                /*
1890                 * If there wasn't a freespace block, the read will
1891                 * return a NULL fbp.  Allocate and initialize a new one.
1892                 */
1893                if (!fbp) {
1894                        error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1895                                                    &fbno);
1896                        if (error)
1897                                return error;
1898
1899                        if (dp->d_ops->db_to_fdb(args->geo, dbno) != fbno) {
1900                                xfs_alert(mp,
1901"%s: dir ino %llu needed freesp block %lld for data block %lld, got %lld ifbno %llu lastfbno %d",
1902                                        __func__, (unsigned long long)dp->i_ino,
1903                                        (long long)dp->d_ops->db_to_fdb(
1904                                                                args->geo, dbno),
1905                                        (long long)dbno, (long long)fbno,
1906                                        (unsigned long long)ifbno, lastfbno);
1907                                if (fblk) {
1908                                        xfs_alert(mp,
1909                                " fblk 0x%p blkno %llu index %d magic 0x%x",
1910                                                fblk,
1911                                                (unsigned long long)fblk->blkno,
1912                                                fblk->index,
1913                                                fblk->magic);
1914                                } else {
1915                                        xfs_alert(mp, " ... fblk is NULL");
1916                                }
1917                                XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1918                                                 XFS_ERRLEVEL_LOW, mp);
1919                                return -EFSCORRUPTED;
1920                        }
1921
1922                        /*
1923                         * Get a buffer for the new block.
1924                         */
1925                        error = xfs_dir3_free_get_buf(args, fbno, &fbp);
1926                        if (error)
1927                                return error;
1928                        free = fbp->b_addr;
1929                        bests = dp->d_ops->free_bests_p(free);
1930                        dp->d_ops->free_hdr_from_disk(&freehdr, free);
1931
1932                        /*
1933                         * Remember the first slot as our empty slot.
1934                         */
1935                        freehdr.firstdb =
1936                                (fbno - xfs_dir2_byte_to_db(args->geo,
1937                                                        XFS_DIR2_FREE_OFFSET)) *
1938                                        dp->d_ops->free_max_bests(args->geo);
1939                } else {
1940                        free = fbp->b_addr;
1941                        bests = dp->d_ops->free_bests_p(free);
1942                        dp->d_ops->free_hdr_from_disk(&freehdr, free);
1943                }
1944
1945                /*
1946                 * Set the freespace block index from the data block number.
1947                 */
1948                findex = dp->d_ops->db_to_fdindex(args->geo, dbno);
1949                /*
1950                 * If it's after the end of the current entries in the
1951                 * freespace block, extend that table.
1952                 */
1953                if (findex >= freehdr.nvalid) {
1954                        ASSERT(findex < dp->d_ops->free_max_bests(args->geo));
1955                        freehdr.nvalid = findex + 1;
1956                        /*
1957                         * Tag new entry so nused will go up.
1958                         */
1959                        bests[findex] = cpu_to_be16(NULLDATAOFF);
1960                }
1961                /*
1962                 * If this entry was for an empty data block
1963                 * (this should always be true) then update the header.
1964                 */
1965                if (bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1966                        freehdr.nused++;
1967                        dp->d_ops->free_hdr_to_disk(fbp->b_addr, &freehdr);
1968                        xfs_dir2_free_log_header(args, fbp);
1969                }
1970                /*
1971                 * Update the real value in the table.
1972                 * We haven't allocated the data entry yet so this will
1973                 * change again.
1974                 */
1975                hdr = dbp->b_addr;
1976                bf = dp->d_ops->data_bestfree_p(hdr);
1977                bests[findex] = bf[0].length;
1978                logfree = 1;
1979        }
1980        /*
1981         * We had a data block so we don't have to make a new one.
1982         */
1983        else {
1984                /*
1985                 * If just checking, we succeeded.
1986                 */
1987                if (args->op_flags & XFS_DA_OP_JUSTCHECK)
1988                        return 0;
1989
1990                /*
1991                 * Read the data block in.
1992                 */
1993                error = xfs_dir3_data_read(tp, dp,
1994                                           xfs_dir2_db_to_da(args->geo, dbno),
1995                                           -1, &dbp);
1996                if (error)
1997                        return error;
1998                hdr = dbp->b_addr;
1999                bf = dp->d_ops->data_bestfree_p(hdr);
2000                logfree = 0;
2001        }
2002        ASSERT(be16_to_cpu(bf[0].length) >= length);
2003        /*
2004         * Point to the existing unused space.
2005         */
2006        dup = (xfs_dir2_data_unused_t *)
2007              ((char *)hdr + be16_to_cpu(bf[0].offset));
2008        needscan = needlog = 0;
2009        /*
2010         * Mark the first part of the unused space, inuse for us.
2011         */
2012        xfs_dir2_data_use_free(args, dbp, dup,
2013                (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
2014                &needlog, &needscan);
2015        /*
2016         * Fill in the new entry and log it.
2017         */
2018        dep = (xfs_dir2_data_entry_t *)dup;
2019        dep->inumber = cpu_to_be64(args->inumber);
2020        dep->namelen = args->namelen;
2021        memcpy(dep->name, args->name, dep->namelen);
2022        dp->d_ops->data_put_ftype(dep, args->filetype);
2023        tagp = dp->d_ops->data_entry_tag_p(dep);
2024        *tagp = cpu_to_be16((char *)dep - (char *)hdr);
2025        xfs_dir2_data_log_entry(args, dbp, dep);
2026        /*
2027         * Rescan the block for bestfree if needed.
2028         */
2029        if (needscan)
2030                xfs_dir2_data_freescan(dp, hdr, &needlog);
2031        /*
2032         * Log the data block header if needed.
2033         */
2034        if (needlog)
2035                xfs_dir2_data_log_header(args, dbp);
2036        /*
2037         * If the freespace entry is now wrong, update it.
2038         */
2039        bests = dp->d_ops->free_bests_p(free); /* gcc is so stupid */
2040        if (be16_to_cpu(bests[findex]) != be16_to_cpu(bf[0].length)) {
2041                bests[findex] = bf[0].length;
2042                logfree = 1;
2043        }
2044        /*
2045         * Log the freespace entry if needed.
2046         */
2047        if (logfree)
2048                xfs_dir2_free_log_bests(args, fbp, findex, findex);
2049        /*
2050         * Return the data block and offset in args, then drop the data block.
2051         */
2052        args->blkno = (xfs_dablk_t)dbno;
2053        args->index = be16_to_cpu(*tagp);
2054        return 0;
2055}
2056
2057/*
2058 * Lookup an entry in a node-format directory.
2059 * All the real work happens in xfs_da3_node_lookup_int.
2060 * The only real output is the inode number of the entry.
2061 */
2062int                                             /* error */
2063xfs_dir2_node_lookup(
2064        xfs_da_args_t   *args)                  /* operation arguments */
2065{
2066        int             error;                  /* error return value */
2067        int             i;                      /* btree level */
2068        int             rval;                   /* operation return value */
2069        xfs_da_state_t  *state;                 /* btree cursor */
2070
2071        trace_xfs_dir2_node_lookup(args);
2072
2073        /*
2074         * Allocate and initialize the btree cursor.
2075         */
2076        state = xfs_da_state_alloc();
2077        state->args = args;
2078        state->mp = args->dp->i_mount;
2079        /*
2080         * Fill in the path to the entry in the cursor.
2081         */
2082        error = xfs_da3_node_lookup_int(state, &rval);
2083        if (error)
2084                rval = error;
2085        else if (rval == -ENOENT && args->cmpresult == XFS_CMP_CASE) {
2086                /* If a CI match, dup the actual name and return -EEXIST */
2087                xfs_dir2_data_entry_t   *dep;
2088
2089                dep = (xfs_dir2_data_entry_t *)
2090                        ((char *)state->extrablk.bp->b_addr +
2091                                                 state->extrablk.index);
2092                rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
2093        }
2094        /*
2095         * Release the btree blocks and leaf block.
2096         */
2097        for (i = 0; i < state->path.active; i++) {
2098                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2099                state->path.blk[i].bp = NULL;
2100        }
2101        /*
2102         * Release the data block if we have it.
2103         */
2104        if (state->extravalid && state->extrablk.bp) {
2105                xfs_trans_brelse(args->trans, state->extrablk.bp);
2106                state->extrablk.bp = NULL;
2107        }
2108        xfs_da_state_free(state);
2109        return rval;
2110}
2111
2112/*
2113 * Remove an entry from a node-format directory.
2114 */
2115int                                             /* error */
2116xfs_dir2_node_removename(
2117        struct xfs_da_args      *args)          /* operation arguments */
2118{
2119        struct xfs_da_state_blk *blk;           /* leaf block */
2120        int                     error;          /* error return value */
2121        int                     rval;           /* operation return value */
2122        struct xfs_da_state     *state;         /* btree cursor */
2123
2124        trace_xfs_dir2_node_removename(args);
2125
2126        /*
2127         * Allocate and initialize the btree cursor.
2128         */
2129        state = xfs_da_state_alloc();
2130        state->args = args;
2131        state->mp = args->dp->i_mount;
2132
2133        /* Look up the entry we're deleting, set up the cursor. */
2134        error = xfs_da3_node_lookup_int(state, &rval);
2135        if (error)
2136                goto out_free;
2137
2138        /* Didn't find it, upper layer screwed up. */
2139        if (rval != -EEXIST) {
2140                error = rval;
2141                goto out_free;
2142        }
2143
2144        blk = &state->path.blk[state->path.active - 1];
2145        ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2146        ASSERT(state->extravalid);
2147        /*
2148         * Remove the leaf and data entries.
2149         * Extrablk refers to the data block.
2150         */
2151        error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
2152                &state->extrablk, &rval);
2153        if (error)
2154                goto out_free;
2155        /*
2156         * Fix the hash values up the btree.
2157         */
2158        xfs_da3_fixhashpath(state, &state->path);
2159        /*
2160         * If we need to join leaf blocks, do it.
2161         */
2162        if (rval && state->path.active > 1)
2163                error = xfs_da3_join(state);
2164        /*
2165         * If no errors so far, try conversion to leaf format.
2166         */
2167        if (!error)
2168                error = xfs_dir2_node_to_leaf(state);
2169out_free:
2170        xfs_da_state_free(state);
2171        return error;
2172}
2173
2174/*
2175 * Replace an entry's inode number in a node-format directory.
2176 */
2177int                                             /* error */
2178xfs_dir2_node_replace(
2179        xfs_da_args_t           *args)          /* operation arguments */
2180{
2181        xfs_da_state_blk_t      *blk;           /* leaf block */
2182        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
2183        xfs_dir2_data_entry_t   *dep;           /* data entry changed */
2184        int                     error;          /* error return value */
2185        int                     i;              /* btree level */
2186        xfs_ino_t               inum;           /* new inode number */
2187        int                     ftype;          /* new file type */
2188        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2189        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
2190        int                     rval;           /* internal return value */
2191        xfs_da_state_t          *state;         /* btree cursor */
2192
2193        trace_xfs_dir2_node_replace(args);
2194
2195        /*
2196         * Allocate and initialize the btree cursor.
2197         */
2198        state = xfs_da_state_alloc();
2199        state->args = args;
2200        state->mp = args->dp->i_mount;
2201
2202        /*
2203         * We have to save new inode number and ftype since
2204         * xfs_da3_node_lookup_int() is going to overwrite them
2205         */
2206        inum = args->inumber;
2207        ftype = args->filetype;
2208
2209        /*
2210         * Lookup the entry to change in the btree.
2211         */
2212        error = xfs_da3_node_lookup_int(state, &rval);
2213        if (error) {
2214                rval = error;
2215        }
2216        /*
2217         * It should be found, since the vnodeops layer has looked it up
2218         * and locked it.  But paranoia is good.
2219         */
2220        if (rval == -EEXIST) {
2221                struct xfs_dir2_leaf_entry *ents;
2222                /*
2223                 * Find the leaf entry.
2224                 */
2225                blk = &state->path.blk[state->path.active - 1];
2226                ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
2227                leaf = blk->bp->b_addr;
2228                ents = args->dp->d_ops->leaf_ents_p(leaf);
2229                lep = &ents[blk->index];
2230                ASSERT(state->extravalid);
2231                /*
2232                 * Point to the data entry.
2233                 */
2234                hdr = state->extrablk.bp->b_addr;
2235                ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
2236                       hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
2237                dep = (xfs_dir2_data_entry_t *)
2238                      ((char *)hdr +
2239                       xfs_dir2_dataptr_to_off(args->geo,
2240                                               be32_to_cpu(lep->address)));
2241                ASSERT(inum != be64_to_cpu(dep->inumber));
2242                /*
2243                 * Fill in the new inode number and log the entry.
2244                 */
2245                dep->inumber = cpu_to_be64(inum);
2246                args->dp->d_ops->data_put_ftype(dep, ftype);
2247                xfs_dir2_data_log_entry(args, state->extrablk.bp, dep);
2248                rval = 0;
2249        }
2250        /*
2251         * Didn't find it, and we're holding a data block.  Drop it.
2252         */
2253        else if (state->extravalid) {
2254                xfs_trans_brelse(args->trans, state->extrablk.bp);
2255                state->extrablk.bp = NULL;
2256        }
2257        /*
2258         * Release all the buffers in the cursor.
2259         */
2260        for (i = 0; i < state->path.active; i++) {
2261                xfs_trans_brelse(args->trans, state->path.blk[i].bp);
2262                state->path.blk[i].bp = NULL;
2263        }
2264        xfs_da_state_free(state);
2265        return rval;
2266}
2267
2268/*
2269 * Trim off a trailing empty freespace block.
2270 * Return (in rvalp) 1 if we did it, 0 if not.
2271 */
2272int                                             /* error */
2273xfs_dir2_node_trim_free(
2274        xfs_da_args_t           *args,          /* operation arguments */
2275        xfs_fileoff_t           fo,             /* free block number */
2276        int                     *rvalp)         /* out: did something */
2277{
2278        struct xfs_buf          *bp;            /* freespace buffer */
2279        xfs_inode_t             *dp;            /* incore directory inode */
2280        int                     error;          /* error return code */
2281        xfs_dir2_free_t         *free;          /* freespace structure */
2282        xfs_trans_t             *tp;            /* transaction pointer */
2283        struct xfs_dir3_icfree_hdr freehdr;
2284
2285        dp = args->dp;
2286        tp = args->trans;
2287
2288        *rvalp = 0;
2289
2290        /*
2291         * Read the freespace block.
2292         */
2293        error = xfs_dir2_free_try_read(tp, dp, fo, &bp);
2294        if (error)
2295                return error;
2296        /*
2297         * There can be holes in freespace.  If fo is a hole, there's
2298         * nothing to do.
2299         */
2300        if (!bp)
2301                return 0;
2302        free = bp->b_addr;
2303        dp->d_ops->free_hdr_from_disk(&freehdr, free);
2304
2305        /*
2306         * If there are used entries, there's nothing to do.
2307         */
2308        if (freehdr.nused > 0) {
2309                xfs_trans_brelse(tp, bp);
2310                return 0;
2311        }
2312        /*
2313         * Blow the block away.
2314         */
2315        error = xfs_dir2_shrink_inode(args,
2316                        xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)fo), bp);
2317        if (error) {
2318                /*
2319                 * Can't fail with ENOSPC since that only happens with no
2320                 * space reservation, when breaking up an extent into two
2321                 * pieces.  This is the last block of an extent.
2322                 */
2323                ASSERT(error != -ENOSPC);
2324                xfs_trans_brelse(tp, bp);
2325                return error;
2326        }
2327        /*
2328         * Return that we succeeded.
2329         */
2330        *rvalp = 1;
2331        return 0;
2332}
2333