linux/fs/xfs/xfs_dir2_leaf.c
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   1/*
   2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3 * Copyright (c) 2013 Red Hat, Inc.
   4 * All Rights Reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it would be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write the Free Software Foundation,
  17 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18 */
  19#include "xfs.h"
  20#include "xfs_fs.h"
  21#include "xfs_types.h"
  22#include "xfs_bit.h"
  23#include "xfs_log.h"
  24#include "xfs_trans.h"
  25#include "xfs_sb.h"
  26#include "xfs_ag.h"
  27#include "xfs_mount.h"
  28#include "xfs_da_btree.h"
  29#include "xfs_bmap_btree.h"
  30#include "xfs_dinode.h"
  31#include "xfs_inode.h"
  32#include "xfs_bmap.h"
  33#include "xfs_dir2_format.h"
  34#include "xfs_dir2_priv.h"
  35#include "xfs_error.h"
  36#include "xfs_trace.h"
  37#include "xfs_buf_item.h"
  38#include "xfs_cksum.h"
  39
  40/*
  41 * Local function declarations.
  42 */
  43static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
  44                                    int *indexp, struct xfs_buf **dbpp);
  45static void xfs_dir3_leaf_log_bests(struct xfs_trans *tp, struct xfs_buf *bp,
  46                                    int first, int last);
  47static void xfs_dir3_leaf_log_tail(struct xfs_trans *tp, struct xfs_buf *bp);
  48
  49/*
  50 * Check the internal consistency of a leaf1 block.
  51 * Pop an assert if something is wrong.
  52 */
  53#ifdef DEBUG
  54#define xfs_dir3_leaf_check(mp, bp) \
  55do { \
  56        if (!xfs_dir3_leaf1_check((mp), (bp))) \
  57                ASSERT(0); \
  58} while (0);
  59
  60STATIC bool
  61xfs_dir3_leaf1_check(
  62        struct xfs_mount        *mp,
  63        struct xfs_buf          *bp)
  64{
  65        struct xfs_dir2_leaf    *leaf = bp->b_addr;
  66        struct xfs_dir3_icleaf_hdr leafhdr;
  67
  68        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
  69
  70        if (leafhdr.magic == XFS_DIR3_LEAF1_MAGIC) {
  71                struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
  72                if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
  73                        return false;
  74        } else if (leafhdr.magic != XFS_DIR2_LEAF1_MAGIC)
  75                return false;
  76
  77        return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
  78}
  79#else
  80#define xfs_dir3_leaf_check(mp, bp)
  81#endif
  82
  83void
  84xfs_dir3_leaf_hdr_from_disk(
  85        struct xfs_dir3_icleaf_hdr      *to,
  86        struct xfs_dir2_leaf            *from)
  87{
  88        if (from->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
  89            from->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC)) {
  90                to->forw = be32_to_cpu(from->hdr.info.forw);
  91                to->back = be32_to_cpu(from->hdr.info.back);
  92                to->magic = be16_to_cpu(from->hdr.info.magic);
  93                to->count = be16_to_cpu(from->hdr.count);
  94                to->stale = be16_to_cpu(from->hdr.stale);
  95        } else {
  96                struct xfs_dir3_leaf_hdr *hdr3 = (struct xfs_dir3_leaf_hdr *)from;
  97
  98                to->forw = be32_to_cpu(hdr3->info.hdr.forw);
  99                to->back = be32_to_cpu(hdr3->info.hdr.back);
 100                to->magic = be16_to_cpu(hdr3->info.hdr.magic);
 101                to->count = be16_to_cpu(hdr3->count);
 102                to->stale = be16_to_cpu(hdr3->stale);
 103        }
 104
 105        ASSERT(to->magic == XFS_DIR2_LEAF1_MAGIC ||
 106               to->magic == XFS_DIR3_LEAF1_MAGIC ||
 107               to->magic == XFS_DIR2_LEAFN_MAGIC ||
 108               to->magic == XFS_DIR3_LEAFN_MAGIC);
 109}
 110
 111void
 112xfs_dir3_leaf_hdr_to_disk(
 113        struct xfs_dir2_leaf            *to,
 114        struct xfs_dir3_icleaf_hdr      *from)
 115{
 116        ASSERT(from->magic == XFS_DIR2_LEAF1_MAGIC ||
 117               from->magic == XFS_DIR3_LEAF1_MAGIC ||
 118               from->magic == XFS_DIR2_LEAFN_MAGIC ||
 119               from->magic == XFS_DIR3_LEAFN_MAGIC);
 120
 121        if (from->magic == XFS_DIR2_LEAF1_MAGIC ||
 122            from->magic == XFS_DIR2_LEAFN_MAGIC) {
 123                to->hdr.info.forw = cpu_to_be32(from->forw);
 124                to->hdr.info.back = cpu_to_be32(from->back);
 125                to->hdr.info.magic = cpu_to_be16(from->magic);
 126                to->hdr.count = cpu_to_be16(from->count);
 127                to->hdr.stale = cpu_to_be16(from->stale);
 128        } else {
 129                struct xfs_dir3_leaf_hdr *hdr3 = (struct xfs_dir3_leaf_hdr *)to;
 130
 131                hdr3->info.hdr.forw = cpu_to_be32(from->forw);
 132                hdr3->info.hdr.back = cpu_to_be32(from->back);
 133                hdr3->info.hdr.magic = cpu_to_be16(from->magic);
 134                hdr3->count = cpu_to_be16(from->count);
 135                hdr3->stale = cpu_to_be16(from->stale);
 136        }
 137}
 138
 139bool
 140xfs_dir3_leaf_check_int(
 141        struct xfs_mount        *mp,
 142        struct xfs_dir3_icleaf_hdr *hdr,
 143        struct xfs_dir2_leaf    *leaf)
 144{
 145        struct xfs_dir2_leaf_entry *ents;
 146        xfs_dir2_leaf_tail_t    *ltp;
 147        int                     stale;
 148        int                     i;
 149
 150        ents = xfs_dir3_leaf_ents_p(leaf);
 151        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 152
 153        /*
 154         * XXX (dgc): This value is not restrictive enough.
 155         * Should factor in the size of the bests table as well.
 156         * We can deduce a value for that from di_size.
 157         */
 158        if (hdr->count > xfs_dir3_max_leaf_ents(mp, leaf))
 159                return false;
 160
 161        /* Leaves and bests don't overlap in leaf format. */
 162        if ((hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
 163             hdr->magic == XFS_DIR3_LEAF1_MAGIC) &&
 164            (char *)&ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
 165                return false;
 166
 167        /* Check hash value order, count stale entries.  */
 168        for (i = stale = 0; i < hdr->count; i++) {
 169                if (i + 1 < hdr->count) {
 170                        if (be32_to_cpu(ents[i].hashval) >
 171                                        be32_to_cpu(ents[i + 1].hashval))
 172                                return false;
 173                }
 174                if (ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 175                        stale++;
 176        }
 177        if (hdr->stale != stale)
 178                return false;
 179        return true;
 180}
 181
 182static bool
 183xfs_dir3_leaf_verify(
 184        struct xfs_buf          *bp,
 185        __uint16_t              magic)
 186{
 187        struct xfs_mount        *mp = bp->b_target->bt_mount;
 188        struct xfs_dir2_leaf    *leaf = bp->b_addr;
 189        struct xfs_dir3_icleaf_hdr leafhdr;
 190
 191        ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 192
 193        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 194        if (xfs_sb_version_hascrc(&mp->m_sb)) {
 195                struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 196
 197                if ((magic == XFS_DIR2_LEAF1_MAGIC &&
 198                     leafhdr.magic != XFS_DIR3_LEAF1_MAGIC) ||
 199                    (magic == XFS_DIR2_LEAFN_MAGIC &&
 200                     leafhdr.magic != XFS_DIR3_LEAFN_MAGIC))
 201                        return false;
 202
 203                if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_uuid))
 204                        return false;
 205                if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
 206                        return false;
 207        } else {
 208                if (leafhdr.magic != magic)
 209                        return false;
 210        }
 211        return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
 212}
 213
 214static void
 215__read_verify(
 216        struct xfs_buf  *bp,
 217        __uint16_t      magic)
 218{
 219        struct xfs_mount        *mp = bp->b_target->bt_mount;
 220
 221        if ((xfs_sb_version_hascrc(&mp->m_sb) &&
 222             !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
 223                                          XFS_DIR3_LEAF_CRC_OFF)) ||
 224            !xfs_dir3_leaf_verify(bp, magic)) {
 225                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 226                xfs_buf_ioerror(bp, EFSCORRUPTED);
 227        }
 228}
 229
 230static void
 231__write_verify(
 232        struct xfs_buf  *bp,
 233        __uint16_t      magic)
 234{
 235        struct xfs_mount        *mp = bp->b_target->bt_mount;
 236        struct xfs_buf_log_item *bip = bp->b_fspriv;
 237        struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
 238
 239        if (!xfs_dir3_leaf_verify(bp, magic)) {
 240                XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 241                xfs_buf_ioerror(bp, EFSCORRUPTED);
 242                return;
 243        }
 244
 245        if (!xfs_sb_version_hascrc(&mp->m_sb))
 246                return;
 247
 248        if (bip)
 249                hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
 250
 251        xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_LEAF_CRC_OFF);
 252}
 253
 254static void
 255xfs_dir3_leaf1_read_verify(
 256        struct xfs_buf  *bp)
 257{
 258        __read_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 259}
 260
 261static void
 262xfs_dir3_leaf1_write_verify(
 263        struct xfs_buf  *bp)
 264{
 265        __write_verify(bp, XFS_DIR2_LEAF1_MAGIC);
 266}
 267
 268static void
 269xfs_dir3_leafn_read_verify(
 270        struct xfs_buf  *bp)
 271{
 272        __read_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 273}
 274
 275static void
 276xfs_dir3_leafn_write_verify(
 277        struct xfs_buf  *bp)
 278{
 279        __write_verify(bp, XFS_DIR2_LEAFN_MAGIC);
 280}
 281
 282const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
 283        .verify_read = xfs_dir3_leaf1_read_verify,
 284        .verify_write = xfs_dir3_leaf1_write_verify,
 285};
 286
 287const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
 288        .verify_read = xfs_dir3_leafn_read_verify,
 289        .verify_write = xfs_dir3_leafn_write_verify,
 290};
 291
 292static int
 293xfs_dir3_leaf_read(
 294        struct xfs_trans        *tp,
 295        struct xfs_inode        *dp,
 296        xfs_dablk_t             fbno,
 297        xfs_daddr_t             mappedbno,
 298        struct xfs_buf          **bpp)
 299{
 300        int                     err;
 301
 302        err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 303                                XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
 304        if (!err && tp)
 305                xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 306        return err;
 307}
 308
 309int
 310xfs_dir3_leafn_read(
 311        struct xfs_trans        *tp,
 312        struct xfs_inode        *dp,
 313        xfs_dablk_t             fbno,
 314        xfs_daddr_t             mappedbno,
 315        struct xfs_buf          **bpp)
 316{
 317        int                     err;
 318
 319        err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 320                                XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
 321        if (!err && tp)
 322                xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 323        return err;
 324}
 325
 326/*
 327 * Initialize a new leaf block, leaf1 or leafn magic accepted.
 328 */
 329static void
 330xfs_dir3_leaf_init(
 331        struct xfs_mount        *mp,
 332        struct xfs_trans        *tp,
 333        struct xfs_buf          *bp,
 334        xfs_ino_t               owner,
 335        __uint16_t              type)
 336{
 337        struct xfs_dir2_leaf    *leaf = bp->b_addr;
 338
 339        ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
 340
 341        if (xfs_sb_version_hascrc(&mp->m_sb)) {
 342                struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
 343
 344                memset(leaf3, 0, sizeof(*leaf3));
 345
 346                leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
 347                                         ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
 348                                         : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
 349                leaf3->info.blkno = cpu_to_be64(bp->b_bn);
 350                leaf3->info.owner = cpu_to_be64(owner);
 351                uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_uuid);
 352        } else {
 353                memset(leaf, 0, sizeof(*leaf));
 354                leaf->hdr.info.magic = cpu_to_be16(type);
 355        }
 356
 357        /*
 358         * If it's a leaf-format directory initialize the tail.
 359         * Caller is responsible for initialising the bests table.
 360         */
 361        if (type == XFS_DIR2_LEAF1_MAGIC) {
 362                struct xfs_dir2_leaf_tail *ltp;
 363
 364                ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 365                ltp->bestcount = 0;
 366                bp->b_ops = &xfs_dir3_leaf1_buf_ops;
 367                xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
 368        } else {
 369                bp->b_ops = &xfs_dir3_leafn_buf_ops;
 370                xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
 371        }
 372}
 373
 374int
 375xfs_dir3_leaf_get_buf(
 376        xfs_da_args_t           *args,
 377        xfs_dir2_db_t           bno,
 378        struct xfs_buf          **bpp,
 379        __uint16_t              magic)
 380{
 381        struct xfs_inode        *dp = args->dp;
 382        struct xfs_trans        *tp = args->trans;
 383        struct xfs_mount        *mp = dp->i_mount;
 384        struct xfs_buf          *bp;
 385        int                     error;
 386
 387        ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
 388        ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
 389               bno < XFS_DIR2_FREE_FIRSTDB(mp));
 390
 391        error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
 392                               XFS_DATA_FORK);
 393        if (error)
 394                return error;
 395
 396        xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
 397        xfs_dir3_leaf_log_header(tp, bp);
 398        if (magic == XFS_DIR2_LEAF1_MAGIC)
 399                xfs_dir3_leaf_log_tail(tp, bp);
 400        *bpp = bp;
 401        return 0;
 402}
 403
 404/*
 405 * Convert a block form directory to a leaf form directory.
 406 */
 407int                                             /* error */
 408xfs_dir2_block_to_leaf(
 409        xfs_da_args_t           *args,          /* operation arguments */
 410        struct xfs_buf          *dbp)           /* input block's buffer */
 411{
 412        __be16                  *bestsp;        /* leaf's bestsp entries */
 413        xfs_dablk_t             blkno;          /* leaf block's bno */
 414        xfs_dir2_data_hdr_t     *hdr;           /* block header */
 415        xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
 416        xfs_dir2_block_tail_t   *btp;           /* block's tail */
 417        xfs_inode_t             *dp;            /* incore directory inode */
 418        int                     error;          /* error return code */
 419        struct xfs_buf          *lbp;           /* leaf block's buffer */
 420        xfs_dir2_db_t           ldb;            /* leaf block's bno */
 421        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 422        xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
 423        xfs_mount_t             *mp;            /* filesystem mount point */
 424        int                     needlog;        /* need to log block header */
 425        int                     needscan;       /* need to rescan bestfree */
 426        xfs_trans_t             *tp;            /* transaction pointer */
 427        struct xfs_dir2_data_free *bf;
 428        struct xfs_dir2_leaf_entry *ents;
 429        struct xfs_dir3_icleaf_hdr leafhdr;
 430
 431        trace_xfs_dir2_block_to_leaf(args);
 432
 433        dp = args->dp;
 434        mp = dp->i_mount;
 435        tp = args->trans;
 436        /*
 437         * Add the leaf block to the inode.
 438         * This interface will only put blocks in the leaf/node range.
 439         * Since that's empty now, we'll get the root (block 0 in range).
 440         */
 441        if ((error = xfs_da_grow_inode(args, &blkno))) {
 442                return error;
 443        }
 444        ldb = xfs_dir2_da_to_db(mp, blkno);
 445        ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
 446        /*
 447         * Initialize the leaf block, get a buffer for it.
 448         */
 449        error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
 450        if (error)
 451                return error;
 452
 453        leaf = lbp->b_addr;
 454        hdr = dbp->b_addr;
 455        xfs_dir3_data_check(dp, dbp);
 456        btp = xfs_dir2_block_tail_p(mp, hdr);
 457        blp = xfs_dir2_block_leaf_p(btp);
 458        bf = xfs_dir3_data_bestfree_p(hdr);
 459        ents = xfs_dir3_leaf_ents_p(leaf);
 460
 461        /*
 462         * Set the counts in the leaf header.
 463         */
 464        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 465        leafhdr.count = be32_to_cpu(btp->count);
 466        leafhdr.stale = be32_to_cpu(btp->stale);
 467        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
 468        xfs_dir3_leaf_log_header(tp, lbp);
 469
 470        /*
 471         * Could compact these but I think we always do the conversion
 472         * after squeezing out stale entries.
 473         */
 474        memcpy(ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
 475        xfs_dir3_leaf_log_ents(tp, lbp, 0, leafhdr.count - 1);
 476        needscan = 0;
 477        needlog = 1;
 478        /*
 479         * Make the space formerly occupied by the leaf entries and block
 480         * tail be free.
 481         */
 482        xfs_dir2_data_make_free(tp, dbp,
 483                (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
 484                (xfs_dir2_data_aoff_t)((char *)hdr + mp->m_dirblksize -
 485                                       (char *)blp),
 486                &needlog, &needscan);
 487        /*
 488         * Fix up the block header, make it a data block.
 489         */
 490        dbp->b_ops = &xfs_dir3_data_buf_ops;
 491        xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
 492        if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
 493                hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
 494        else
 495                hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
 496
 497        if (needscan)
 498                xfs_dir2_data_freescan(mp, hdr, &needlog);
 499        /*
 500         * Set up leaf tail and bests table.
 501         */
 502        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 503        ltp->bestcount = cpu_to_be32(1);
 504        bestsp = xfs_dir2_leaf_bests_p(ltp);
 505        bestsp[0] =  bf[0].length;
 506        /*
 507         * Log the data header and leaf bests table.
 508         */
 509        if (needlog)
 510                xfs_dir2_data_log_header(tp, dbp);
 511        xfs_dir3_leaf_check(mp, lbp);
 512        xfs_dir3_data_check(dp, dbp);
 513        xfs_dir3_leaf_log_bests(tp, lbp, 0, 0);
 514        return 0;
 515}
 516
 517STATIC void
 518xfs_dir3_leaf_find_stale(
 519        struct xfs_dir3_icleaf_hdr *leafhdr,
 520        struct xfs_dir2_leaf_entry *ents,
 521        int                     index,
 522        int                     *lowstale,
 523        int                     *highstale)
 524{
 525        /*
 526         * Find the first stale entry before our index, if any.
 527         */
 528        for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
 529                if (ents[*lowstale].address ==
 530                    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 531                        break;
 532        }
 533
 534        /*
 535         * Find the first stale entry at or after our index, if any.
 536         * Stop if the result would require moving more entries than using
 537         * lowstale.
 538         */
 539        for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
 540                if (ents[*highstale].address ==
 541                    cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 542                        break;
 543                if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
 544                        break;
 545        }
 546}
 547
 548struct xfs_dir2_leaf_entry *
 549xfs_dir3_leaf_find_entry(
 550        struct xfs_dir3_icleaf_hdr *leafhdr,
 551        struct xfs_dir2_leaf_entry *ents,
 552        int                     index,          /* leaf table position */
 553        int                     compact,        /* need to compact leaves */
 554        int                     lowstale,       /* index of prev stale leaf */
 555        int                     highstale,      /* index of next stale leaf */
 556        int                     *lfloglow,      /* low leaf logging index */
 557        int                     *lfloghigh)     /* high leaf logging index */
 558{
 559        if (!leafhdr->stale) {
 560                xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
 561
 562                /*
 563                 * Now we need to make room to insert the leaf entry.
 564                 *
 565                 * If there are no stale entries, just insert a hole at index.
 566                 */
 567                lep = &ents[index];
 568                if (index < leafhdr->count)
 569                        memmove(lep + 1, lep,
 570                                (leafhdr->count - index) * sizeof(*lep));
 571
 572                /*
 573                 * Record low and high logging indices for the leaf.
 574                 */
 575                *lfloglow = index;
 576                *lfloghigh = leafhdr->count++;
 577                return lep;
 578        }
 579
 580        /*
 581         * There are stale entries.
 582         *
 583         * We will use one of them for the new entry.  It's probably not at
 584         * the right location, so we'll have to shift some up or down first.
 585         *
 586         * If we didn't compact before, we need to find the nearest stale
 587         * entries before and after our insertion point.
 588         */
 589        if (compact == 0)
 590                xfs_dir3_leaf_find_stale(leafhdr, ents, index,
 591                                         &lowstale, &highstale);
 592
 593        /*
 594         * If the low one is better, use it.
 595         */
 596        if (lowstale >= 0 &&
 597            (highstale == leafhdr->count ||
 598             index - lowstale - 1 < highstale - index)) {
 599                ASSERT(index - lowstale - 1 >= 0);
 600                ASSERT(ents[lowstale].address ==
 601                       cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 602
 603                /*
 604                 * Copy entries up to cover the stale entry and make room
 605                 * for the new entry.
 606                 */
 607                if (index - lowstale - 1 > 0) {
 608                        memmove(&ents[lowstale], &ents[lowstale + 1],
 609                                (index - lowstale - 1) *
 610                                        sizeof(xfs_dir2_leaf_entry_t));
 611                }
 612                *lfloglow = MIN(lowstale, *lfloglow);
 613                *lfloghigh = MAX(index - 1, *lfloghigh);
 614                leafhdr->stale--;
 615                return &ents[index - 1];
 616        }
 617
 618        /*
 619         * The high one is better, so use that one.
 620         */
 621        ASSERT(highstale - index >= 0);
 622        ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
 623
 624        /*
 625         * Copy entries down to cover the stale entry and make room for the
 626         * new entry.
 627         */
 628        if (highstale - index > 0) {
 629                memmove(&ents[index + 1], &ents[index],
 630                        (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
 631        }
 632        *lfloglow = MIN(index, *lfloglow);
 633        *lfloghigh = MAX(highstale, *lfloghigh);
 634        leafhdr->stale--;
 635        return &ents[index];
 636}
 637
 638/*
 639 * Add an entry to a leaf form directory.
 640 */
 641int                                             /* error */
 642xfs_dir2_leaf_addname(
 643        xfs_da_args_t           *args)          /* operation arguments */
 644{
 645        __be16                  *bestsp;        /* freespace table in leaf */
 646        int                     compact;        /* need to compact leaves */
 647        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
 648        struct xfs_buf          *dbp;           /* data block buffer */
 649        xfs_dir2_data_entry_t   *dep;           /* data block entry */
 650        xfs_inode_t             *dp;            /* incore directory inode */
 651        xfs_dir2_data_unused_t  *dup;           /* data unused entry */
 652        int                     error;          /* error return value */
 653        int                     grown;          /* allocated new data block */
 654        int                     highstale;      /* index of next stale leaf */
 655        int                     i;              /* temporary, index */
 656        int                     index;          /* leaf table position */
 657        struct xfs_buf          *lbp;           /* leaf's buffer */
 658        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
 659        int                     length;         /* length of new entry */
 660        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
 661        int                     lfloglow;       /* low leaf logging index */
 662        int                     lfloghigh;      /* high leaf logging index */
 663        int                     lowstale;       /* index of prev stale leaf */
 664        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
 665        xfs_mount_t             *mp;            /* filesystem mount point */
 666        int                     needbytes;      /* leaf block bytes needed */
 667        int                     needlog;        /* need to log data header */
 668        int                     needscan;       /* need to rescan data free */
 669        __be16                  *tagp;          /* end of data entry */
 670        xfs_trans_t             *tp;            /* transaction pointer */
 671        xfs_dir2_db_t           use_block;      /* data block number */
 672        struct xfs_dir2_data_free *bf;          /* bestfree table */
 673        struct xfs_dir2_leaf_entry *ents;
 674        struct xfs_dir3_icleaf_hdr leafhdr;
 675
 676        trace_xfs_dir2_leaf_addname(args);
 677
 678        dp = args->dp;
 679        tp = args->trans;
 680        mp = dp->i_mount;
 681
 682        error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
 683        if (error)
 684                return error;
 685
 686        /*
 687         * Look up the entry by hash value and name.
 688         * We know it's not there, our caller has already done a lookup.
 689         * So the index is of the entry to insert in front of.
 690         * But if there are dup hash values the index is of the first of those.
 691         */
 692        index = xfs_dir2_leaf_search_hash(args, lbp);
 693        leaf = lbp->b_addr;
 694        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
 695        ents = xfs_dir3_leaf_ents_p(leaf);
 696        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
 697        bestsp = xfs_dir2_leaf_bests_p(ltp);
 698        length = xfs_dir2_data_entsize(args->namelen);
 699
 700        /*
 701         * See if there are any entries with the same hash value
 702         * and space in their block for the new entry.
 703         * This is good because it puts multiple same-hash value entries
 704         * in a data block, improving the lookup of those entries.
 705         */
 706        for (use_block = -1, lep = &ents[index];
 707             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
 708             index++, lep++) {
 709                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
 710                        continue;
 711                i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
 712                ASSERT(i < be32_to_cpu(ltp->bestcount));
 713                ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
 714                if (be16_to_cpu(bestsp[i]) >= length) {
 715                        use_block = i;
 716                        break;
 717                }
 718        }
 719        /*
 720         * Didn't find a block yet, linear search all the data blocks.
 721         */
 722        if (use_block == -1) {
 723                for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
 724                        /*
 725                         * Remember a block we see that's missing.
 726                         */
 727                        if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
 728                            use_block == -1)
 729                                use_block = i;
 730                        else if (be16_to_cpu(bestsp[i]) >= length) {
 731                                use_block = i;
 732                                break;
 733                        }
 734                }
 735        }
 736        /*
 737         * How many bytes do we need in the leaf block?
 738         */
 739        needbytes = 0;
 740        if (!leafhdr.stale)
 741                needbytes += sizeof(xfs_dir2_leaf_entry_t);
 742        if (use_block == -1)
 743                needbytes += sizeof(xfs_dir2_data_off_t);
 744
 745        /*
 746         * Now kill use_block if it refers to a missing block, so we
 747         * can use it as an indication of allocation needed.
 748         */
 749        if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
 750                use_block = -1;
 751        /*
 752         * If we don't have enough free bytes but we can make enough
 753         * by compacting out stale entries, we'll do that.
 754         */
 755        if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
 756            leafhdr.stale > 1)
 757                compact = 1;
 758
 759        /*
 760         * Otherwise if we don't have enough free bytes we need to
 761         * convert to node form.
 762         */
 763        else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
 764                /*
 765                 * Just checking or no space reservation, give up.
 766                 */
 767                if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
 768                                                        args->total == 0) {
 769                        xfs_trans_brelse(tp, lbp);
 770                        return XFS_ERROR(ENOSPC);
 771                }
 772                /*
 773                 * Convert to node form.
 774                 */
 775                error = xfs_dir2_leaf_to_node(args, lbp);
 776                if (error)
 777                        return error;
 778                /*
 779                 * Then add the new entry.
 780                 */
 781                return xfs_dir2_node_addname(args);
 782        }
 783        /*
 784         * Otherwise it will fit without compaction.
 785         */
 786        else
 787                compact = 0;
 788        /*
 789         * If just checking, then it will fit unless we needed to allocate
 790         * a new data block.
 791         */
 792        if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
 793                xfs_trans_brelse(tp, lbp);
 794                return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
 795        }
 796        /*
 797         * If no allocations are allowed, return now before we've
 798         * changed anything.
 799         */
 800        if (args->total == 0 && use_block == -1) {
 801                xfs_trans_brelse(tp, lbp);
 802                return XFS_ERROR(ENOSPC);
 803        }
 804        /*
 805         * Need to compact the leaf entries, removing stale ones.
 806         * Leave one stale entry behind - the one closest to our
 807         * insertion index - and we'll shift that one to our insertion
 808         * point later.
 809         */
 810        if (compact) {
 811                xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
 812                        &highstale, &lfloglow, &lfloghigh);
 813        }
 814        /*
 815         * There are stale entries, so we'll need log-low and log-high
 816         * impossibly bad values later.
 817         */
 818        else if (leafhdr.stale) {
 819                lfloglow = leafhdr.count;
 820                lfloghigh = -1;
 821        }
 822        /*
 823         * If there was no data block space found, we need to allocate
 824         * a new one.
 825         */
 826        if (use_block == -1) {
 827                /*
 828                 * Add the new data block.
 829                 */
 830                if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
 831                                &use_block))) {
 832                        xfs_trans_brelse(tp, lbp);
 833                        return error;
 834                }
 835                /*
 836                 * Initialize the block.
 837                 */
 838                if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
 839                        xfs_trans_brelse(tp, lbp);
 840                        return error;
 841                }
 842                /*
 843                 * If we're adding a new data block on the end we need to
 844                 * extend the bests table.  Copy it up one entry.
 845                 */
 846                if (use_block >= be32_to_cpu(ltp->bestcount)) {
 847                        bestsp--;
 848                        memmove(&bestsp[0], &bestsp[1],
 849                                be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
 850                        be32_add_cpu(&ltp->bestcount, 1);
 851                        xfs_dir3_leaf_log_tail(tp, lbp);
 852                        xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
 853                }
 854                /*
 855                 * If we're filling in a previously empty block just log it.
 856                 */
 857                else
 858                        xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 859                hdr = dbp->b_addr;
 860                bf = xfs_dir3_data_bestfree_p(hdr);
 861                bestsp[use_block] = bf[0].length;
 862                grown = 1;
 863        } else {
 864                /*
 865                 * Already had space in some data block.
 866                 * Just read that one in.
 867                 */
 868                error = xfs_dir3_data_read(tp, dp,
 869                                           xfs_dir2_db_to_da(mp, use_block),
 870                                           -1, &dbp);
 871                if (error) {
 872                        xfs_trans_brelse(tp, lbp);
 873                        return error;
 874                }
 875                hdr = dbp->b_addr;
 876                bf = xfs_dir3_data_bestfree_p(hdr);
 877                grown = 0;
 878        }
 879        /*
 880         * Point to the biggest freespace in our data block.
 881         */
 882        dup = (xfs_dir2_data_unused_t *)
 883              ((char *)hdr + be16_to_cpu(bf[0].offset));
 884        ASSERT(be16_to_cpu(dup->length) >= length);
 885        needscan = needlog = 0;
 886        /*
 887         * Mark the initial part of our freespace in use for the new entry.
 888         */
 889        xfs_dir2_data_use_free(tp, dbp, dup,
 890                (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
 891                &needlog, &needscan);
 892        /*
 893         * Initialize our new entry (at last).
 894         */
 895        dep = (xfs_dir2_data_entry_t *)dup;
 896        dep->inumber = cpu_to_be64(args->inumber);
 897        dep->namelen = args->namelen;
 898        memcpy(dep->name, args->name, dep->namelen);
 899        tagp = xfs_dir2_data_entry_tag_p(dep);
 900        *tagp = cpu_to_be16((char *)dep - (char *)hdr);
 901        /*
 902         * Need to scan fix up the bestfree table.
 903         */
 904        if (needscan)
 905                xfs_dir2_data_freescan(mp, hdr, &needlog);
 906        /*
 907         * Need to log the data block's header.
 908         */
 909        if (needlog)
 910                xfs_dir2_data_log_header(tp, dbp);
 911        xfs_dir2_data_log_entry(tp, dbp, dep);
 912        /*
 913         * If the bests table needs to be changed, do it.
 914         * Log the change unless we've already done that.
 915         */
 916        if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
 917                bestsp[use_block] = bf[0].length;
 918                if (!grown)
 919                        xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
 920        }
 921
 922        lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
 923                                       highstale, &lfloglow, &lfloghigh);
 924
 925        /*
 926         * Fill in the new leaf entry.
 927         */
 928        lep->hashval = cpu_to_be32(args->hashval);
 929        lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
 930                                be16_to_cpu(*tagp)));
 931        /*
 932         * Log the leaf fields and give up the buffers.
 933         */
 934        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
 935        xfs_dir3_leaf_log_header(tp, lbp);
 936        xfs_dir3_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
 937        xfs_dir3_leaf_check(mp, lbp);
 938        xfs_dir3_data_check(dp, dbp);
 939        return 0;
 940}
 941
 942/*
 943 * Compact out any stale entries in the leaf.
 944 * Log the header and changed leaf entries, if any.
 945 */
 946void
 947xfs_dir3_leaf_compact(
 948        xfs_da_args_t   *args,          /* operation arguments */
 949        struct xfs_dir3_icleaf_hdr *leafhdr,
 950        struct xfs_buf  *bp)            /* leaf buffer */
 951{
 952        int             from;           /* source leaf index */
 953        xfs_dir2_leaf_t *leaf;          /* leaf structure */
 954        int             loglow;         /* first leaf entry to log */
 955        int             to;             /* target leaf index */
 956        struct xfs_dir2_leaf_entry *ents;
 957
 958        leaf = bp->b_addr;
 959        if (!leafhdr->stale)
 960                return;
 961
 962        /*
 963         * Compress out the stale entries in place.
 964         */
 965        ents = xfs_dir3_leaf_ents_p(leaf);
 966        for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
 967                if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 968                        continue;
 969                /*
 970                 * Only actually copy the entries that are different.
 971                 */
 972                if (from > to) {
 973                        if (loglow == -1)
 974                                loglow = to;
 975                        ents[to] = ents[from];
 976                }
 977                to++;
 978        }
 979        /*
 980         * Update and log the header, log the leaf entries.
 981         */
 982        ASSERT(leafhdr->stale == from - to);
 983        leafhdr->count -= leafhdr->stale;
 984        leafhdr->stale = 0;
 985
 986        xfs_dir3_leaf_hdr_to_disk(leaf, leafhdr);
 987        xfs_dir3_leaf_log_header(args->trans, bp);
 988        if (loglow != -1)
 989                xfs_dir3_leaf_log_ents(args->trans, bp, loglow, to - 1);
 990}
 991
 992/*
 993 * Compact the leaf entries, removing stale ones.
 994 * Leave one stale entry behind - the one closest to our
 995 * insertion index - and the caller will shift that one to our insertion
 996 * point later.
 997 * Return new insertion index, where the remaining stale entry is,
 998 * and leaf logging indices.
 999 */
1000void
1001xfs_dir3_leaf_compact_x1(
1002        struct xfs_dir3_icleaf_hdr *leafhdr,
1003        struct xfs_dir2_leaf_entry *ents,
1004        int             *indexp,        /* insertion index */
1005        int             *lowstalep,     /* out: stale entry before us */
1006        int             *highstalep,    /* out: stale entry after us */
1007        int             *lowlogp,       /* out: low log index */
1008        int             *highlogp)      /* out: high log index */
1009{
1010        int             from;           /* source copy index */
1011        int             highstale;      /* stale entry at/after index */
1012        int             index;          /* insertion index */
1013        int             keepstale;      /* source index of kept stale */
1014        int             lowstale;       /* stale entry before index */
1015        int             newindex=0;     /* new insertion index */
1016        int             to;             /* destination copy index */
1017
1018        ASSERT(leafhdr->stale > 1);
1019        index = *indexp;
1020
1021        xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
1022
1023        /*
1024         * Pick the better of lowstale and highstale.
1025         */
1026        if (lowstale >= 0 &&
1027            (highstale == leafhdr->count ||
1028             index - lowstale <= highstale - index))
1029                keepstale = lowstale;
1030        else
1031                keepstale = highstale;
1032        /*
1033         * Copy the entries in place, removing all the stale entries
1034         * except keepstale.
1035         */
1036        for (from = to = 0; from < leafhdr->count; from++) {
1037                /*
1038                 * Notice the new value of index.
1039                 */
1040                if (index == from)
1041                        newindex = to;
1042                if (from != keepstale &&
1043                    ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1044                        if (from == to)
1045                                *lowlogp = to;
1046                        continue;
1047                }
1048                /*
1049                 * Record the new keepstale value for the insertion.
1050                 */
1051                if (from == keepstale)
1052                        lowstale = highstale = to;
1053                /*
1054                 * Copy only the entries that have moved.
1055                 */
1056                if (from > to)
1057                        ents[to] = ents[from];
1058                to++;
1059        }
1060        ASSERT(from > to);
1061        /*
1062         * If the insertion point was past the last entry,
1063         * set the new insertion point accordingly.
1064         */
1065        if (index == from)
1066                newindex = to;
1067        *indexp = newindex;
1068        /*
1069         * Adjust the leaf header values.
1070         */
1071        leafhdr->count -= from - to;
1072        leafhdr->stale = 1;
1073        /*
1074         * Remember the low/high stale value only in the "right"
1075         * direction.
1076         */
1077        if (lowstale >= newindex)
1078                lowstale = -1;
1079        else
1080                highstale = leafhdr->count;
1081        *highlogp = leafhdr->count - 1;
1082        *lowstalep = lowstale;
1083        *highstalep = highstale;
1084}
1085
1086struct xfs_dir2_leaf_map_info {
1087        xfs_extlen_t    map_blocks;     /* number of fsbs in map */
1088        xfs_dablk_t     map_off;        /* last mapped file offset */
1089        int             map_size;       /* total entries in *map */
1090        int             map_valid;      /* valid entries in *map */
1091        int             nmap;           /* mappings to ask xfs_bmapi */
1092        xfs_dir2_db_t   curdb;          /* db for current block */
1093        int             ra_current;     /* number of read-ahead blks */
1094        int             ra_index;       /* *map index for read-ahead */
1095        int             ra_offset;      /* map entry offset for ra */
1096        int             ra_want;        /* readahead count wanted */
1097        struct xfs_bmbt_irec map[];     /* map vector for blocks */
1098};
1099
1100STATIC int
1101xfs_dir2_leaf_readbuf(
1102        struct xfs_inode        *dp,
1103        size_t                  bufsize,
1104        struct xfs_dir2_leaf_map_info *mip,
1105        xfs_dir2_off_t          *curoff,
1106        struct xfs_buf          **bpp)
1107{
1108        struct xfs_mount        *mp = dp->i_mount;
1109        struct xfs_buf          *bp = *bpp;
1110        struct xfs_bmbt_irec    *map = mip->map;
1111        struct blk_plug         plug;
1112        int                     error = 0;
1113        int                     length;
1114        int                     i;
1115        int                     j;
1116
1117        /*
1118         * If we have a buffer, we need to release it and
1119         * take it out of the mapping.
1120         */
1121
1122        if (bp) {
1123                xfs_trans_brelse(NULL, bp);
1124                bp = NULL;
1125                mip->map_blocks -= mp->m_dirblkfsbs;
1126                /*
1127                 * Loop to get rid of the extents for the
1128                 * directory block.
1129                 */
1130                for (i = mp->m_dirblkfsbs; i > 0; ) {
1131                        j = min_t(int, map->br_blockcount, i);
1132                        map->br_blockcount -= j;
1133                        map->br_startblock += j;
1134                        map->br_startoff += j;
1135                        /*
1136                         * If mapping is done, pitch it from
1137                         * the table.
1138                         */
1139                        if (!map->br_blockcount && --mip->map_valid)
1140                                memmove(&map[0], &map[1],
1141                                        sizeof(map[0]) * mip->map_valid);
1142                        i -= j;
1143                }
1144        }
1145
1146        /*
1147         * Recalculate the readahead blocks wanted.
1148         */
1149        mip->ra_want = howmany(bufsize + mp->m_dirblksize,
1150                               mp->m_sb.sb_blocksize) - 1;
1151        ASSERT(mip->ra_want >= 0);
1152
1153        /*
1154         * If we don't have as many as we want, and we haven't
1155         * run out of data blocks, get some more mappings.
1156         */
1157        if (1 + mip->ra_want > mip->map_blocks &&
1158            mip->map_off < xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
1159                /*
1160                 * Get more bmaps, fill in after the ones
1161                 * we already have in the table.
1162                 */
1163                mip->nmap = mip->map_size - mip->map_valid;
1164                error = xfs_bmapi_read(dp, mip->map_off,
1165                                xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET) -
1166                                                                mip->map_off,
1167                                &map[mip->map_valid], &mip->nmap, 0);
1168
1169                /*
1170                 * Don't know if we should ignore this or try to return an
1171                 * error.  The trouble with returning errors is that readdir
1172                 * will just stop without actually passing the error through.
1173                 */
1174                if (error)
1175                        goto out;       /* XXX */
1176
1177                /*
1178                 * If we got all the mappings we asked for, set the final map
1179                 * offset based on the last bmap value received.  Otherwise,
1180                 * we've reached the end.
1181                 */
1182                if (mip->nmap == mip->map_size - mip->map_valid) {
1183                        i = mip->map_valid + mip->nmap - 1;
1184                        mip->map_off = map[i].br_startoff + map[i].br_blockcount;
1185                } else
1186                        mip->map_off = xfs_dir2_byte_to_da(mp,
1187                                                        XFS_DIR2_LEAF_OFFSET);
1188
1189                /*
1190                 * Look for holes in the mapping, and eliminate them.  Count up
1191                 * the valid blocks.
1192                 */
1193                for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
1194                        if (map[i].br_startblock == HOLESTARTBLOCK) {
1195                                mip->nmap--;
1196                                length = mip->map_valid + mip->nmap - i;
1197                                if (length)
1198                                        memmove(&map[i], &map[i + 1],
1199                                                sizeof(map[i]) * length);
1200                        } else {
1201                                mip->map_blocks += map[i].br_blockcount;
1202                                i++;
1203                        }
1204                }
1205                mip->map_valid += mip->nmap;
1206        }
1207
1208        /*
1209         * No valid mappings, so no more data blocks.
1210         */
1211        if (!mip->map_valid) {
1212                *curoff = xfs_dir2_da_to_byte(mp, mip->map_off);
1213                goto out;
1214        }
1215
1216        /*
1217         * Read the directory block starting at the first mapping.
1218         */
1219        mip->curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
1220        error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
1221                        map->br_blockcount >= mp->m_dirblkfsbs ?
1222                            XFS_FSB_TO_DADDR(mp, map->br_startblock) : -1, &bp);
1223
1224        /*
1225         * Should just skip over the data block instead of giving up.
1226         */
1227        if (error)
1228                goto out;       /* XXX */
1229
1230        /*
1231         * Adjust the current amount of read-ahead: we just read a block that
1232         * was previously ra.
1233         */
1234        if (mip->ra_current)
1235                mip->ra_current -= mp->m_dirblkfsbs;
1236
1237        /*
1238         * Do we need more readahead?
1239         */
1240        blk_start_plug(&plug);
1241        for (mip->ra_index = mip->ra_offset = i = 0;
1242             mip->ra_want > mip->ra_current && i < mip->map_blocks;
1243             i += mp->m_dirblkfsbs) {
1244                ASSERT(mip->ra_index < mip->map_valid);
1245                /*
1246                 * Read-ahead a contiguous directory block.
1247                 */
1248                if (i > mip->ra_current &&
1249                    map[mip->ra_index].br_blockcount >= mp->m_dirblkfsbs) {
1250                        xfs_dir3_data_readahead(NULL, dp,
1251                                map[mip->ra_index].br_startoff + mip->ra_offset,
1252                                XFS_FSB_TO_DADDR(mp,
1253                                        map[mip->ra_index].br_startblock +
1254                                                        mip->ra_offset));
1255                        mip->ra_current = i;
1256                }
1257
1258                /*
1259                 * Read-ahead a non-contiguous directory block.  This doesn't
1260                 * use our mapping, but this is a very rare case.
1261                 */
1262                else if (i > mip->ra_current) {
1263                        xfs_dir3_data_readahead(NULL, dp,
1264                                        map[mip->ra_index].br_startoff +
1265                                                        mip->ra_offset, -1);
1266                        mip->ra_current = i;
1267                }
1268
1269                /*
1270                 * Advance offset through the mapping table.
1271                 */
1272                for (j = 0; j < mp->m_dirblkfsbs; j++) {
1273                        /*
1274                         * The rest of this extent but not more than a dir
1275                         * block.
1276                         */
1277                        length = min_t(int, mp->m_dirblkfsbs,
1278                                        map[mip->ra_index].br_blockcount -
1279                                                        mip->ra_offset);
1280                        j += length;
1281                        mip->ra_offset += length;
1282
1283                        /*
1284                         * Advance to the next mapping if this one is used up.
1285                         */
1286                        if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
1287                                mip->ra_offset = 0;
1288                                mip->ra_index++;
1289                        }
1290                }
1291        }
1292        blk_finish_plug(&plug);
1293
1294out:
1295        *bpp = bp;
1296        return error;
1297}
1298
1299/*
1300 * Getdents (readdir) for leaf and node directories.
1301 * This reads the data blocks only, so is the same for both forms.
1302 */
1303int                                             /* error */
1304xfs_dir2_leaf_getdents(
1305        xfs_inode_t             *dp,            /* incore directory inode */
1306        struct dir_context      *ctx,
1307        size_t                  bufsize)
1308{
1309        struct xfs_buf          *bp = NULL;     /* data block buffer */
1310        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1311        xfs_dir2_data_entry_t   *dep;           /* data entry */
1312        xfs_dir2_data_unused_t  *dup;           /* unused entry */
1313        int                     error = 0;      /* error return value */
1314        int                     length;         /* temporary length value */
1315        xfs_mount_t             *mp;            /* filesystem mount point */
1316        int                     byteoff;        /* offset in current block */
1317        xfs_dir2_off_t          curoff;         /* current overall offset */
1318        xfs_dir2_off_t          newoff;         /* new curoff after new blk */
1319        char                    *ptr = NULL;    /* pointer to current data */
1320        struct xfs_dir2_leaf_map_info *map_info;
1321
1322        /*
1323         * If the offset is at or past the largest allowed value,
1324         * give up right away.
1325         */
1326        if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
1327                return 0;
1328
1329        mp = dp->i_mount;
1330
1331        /*
1332         * Set up to bmap a number of blocks based on the caller's
1333         * buffer size, the directory block size, and the filesystem
1334         * block size.
1335         */
1336        length = howmany(bufsize + mp->m_dirblksize,
1337                                     mp->m_sb.sb_blocksize);
1338        map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
1339                                (length * sizeof(struct xfs_bmbt_irec)),
1340                               KM_SLEEP | KM_NOFS);
1341        map_info->map_size = length;
1342
1343        /*
1344         * Inside the loop we keep the main offset value as a byte offset
1345         * in the directory file.
1346         */
1347        curoff = xfs_dir2_dataptr_to_byte(mp, ctx->pos);
1348
1349        /*
1350         * Force this conversion through db so we truncate the offset
1351         * down to get the start of the data block.
1352         */
1353        map_info->map_off = xfs_dir2_db_to_da(mp,
1354                                              xfs_dir2_byte_to_db(mp, curoff));
1355
1356        /*
1357         * Loop over directory entries until we reach the end offset.
1358         * Get more blocks and readahead as necessary.
1359         */
1360        while (curoff < XFS_DIR2_LEAF_OFFSET) {
1361                /*
1362                 * If we have no buffer, or we're off the end of the
1363                 * current buffer, need to get another one.
1364                 */
1365                if (!bp || ptr >= (char *)bp->b_addr + mp->m_dirblksize) {
1366
1367                        error = xfs_dir2_leaf_readbuf(dp, bufsize, map_info,
1368                                                      &curoff, &bp);
1369                        if (error || !map_info->map_valid)
1370                                break;
1371
1372                        /*
1373                         * Having done a read, we need to set a new offset.
1374                         */
1375                        newoff = xfs_dir2_db_off_to_byte(mp, map_info->curdb, 0);
1376                        /*
1377                         * Start of the current block.
1378                         */
1379                        if (curoff < newoff)
1380                                curoff = newoff;
1381                        /*
1382                         * Make sure we're in the right block.
1383                         */
1384                        else if (curoff > newoff)
1385                                ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
1386                                       map_info->curdb);
1387                        hdr = bp->b_addr;
1388                        xfs_dir3_data_check(dp, bp);
1389                        /*
1390                         * Find our position in the block.
1391                         */
1392                        ptr = (char *)xfs_dir3_data_entry_p(hdr);
1393                        byteoff = xfs_dir2_byte_to_off(mp, curoff);
1394                        /*
1395                         * Skip past the header.
1396                         */
1397                        if (byteoff == 0)
1398                                curoff += xfs_dir3_data_entry_offset(hdr);
1399                        /*
1400                         * Skip past entries until we reach our offset.
1401                         */
1402                        else {
1403                                while ((char *)ptr - (char *)hdr < byteoff) {
1404                                        dup = (xfs_dir2_data_unused_t *)ptr;
1405
1406                                        if (be16_to_cpu(dup->freetag)
1407                                                  == XFS_DIR2_DATA_FREE_TAG) {
1408
1409                                                length = be16_to_cpu(dup->length);
1410                                                ptr += length;
1411                                                continue;
1412                                        }
1413                                        dep = (xfs_dir2_data_entry_t *)ptr;
1414                                        length =
1415                                           xfs_dir2_data_entsize(dep->namelen);
1416                                        ptr += length;
1417                                }
1418                                /*
1419                                 * Now set our real offset.
1420                                 */
1421                                curoff =
1422                                        xfs_dir2_db_off_to_byte(mp,
1423                                            xfs_dir2_byte_to_db(mp, curoff),
1424                                            (char *)ptr - (char *)hdr);
1425                                if (ptr >= (char *)hdr + mp->m_dirblksize) {
1426                                        continue;
1427                                }
1428                        }
1429                }
1430                /*
1431                 * We have a pointer to an entry.
1432                 * Is it a live one?
1433                 */
1434                dup = (xfs_dir2_data_unused_t *)ptr;
1435                /*
1436                 * No, it's unused, skip over it.
1437                 */
1438                if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
1439                        length = be16_to_cpu(dup->length);
1440                        ptr += length;
1441                        curoff += length;
1442                        continue;
1443                }
1444
1445                dep = (xfs_dir2_data_entry_t *)ptr;
1446                length = xfs_dir2_data_entsize(dep->namelen);
1447
1448                ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
1449                if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
1450                            be64_to_cpu(dep->inumber), DT_UNKNOWN))
1451                        break;
1452
1453                /*
1454                 * Advance to next entry in the block.
1455                 */
1456                ptr += length;
1457                curoff += length;
1458                /* bufsize may have just been a guess; don't go negative */
1459                bufsize = bufsize > length ? bufsize - length : 0;
1460        }
1461
1462        /*
1463         * All done.  Set output offset value to current offset.
1464         */
1465        if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
1466                ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
1467        else
1468                ctx->pos = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
1469        kmem_free(map_info);
1470        if (bp)
1471                xfs_trans_brelse(NULL, bp);
1472        return error;
1473}
1474
1475
1476/*
1477 * Log the bests entries indicated from a leaf1 block.
1478 */
1479static void
1480xfs_dir3_leaf_log_bests(
1481        xfs_trans_t             *tp,            /* transaction pointer */
1482        struct xfs_buf          *bp,            /* leaf buffer */
1483        int                     first,          /* first entry to log */
1484        int                     last)           /* last entry to log */
1485{
1486        __be16                  *firstb;        /* pointer to first entry */
1487        __be16                  *lastb;         /* pointer to last entry */
1488        struct xfs_dir2_leaf    *leaf = bp->b_addr;
1489        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1490
1491        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1492               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1493
1494        ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1495        firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1496        lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1497        xfs_trans_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1498                (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1499}
1500
1501/*
1502 * Log the leaf entries indicated from a leaf1 or leafn block.
1503 */
1504void
1505xfs_dir3_leaf_log_ents(
1506        xfs_trans_t             *tp,            /* transaction pointer */
1507        struct xfs_buf          *bp,            /* leaf buffer */
1508        int                     first,          /* first entry to log */
1509        int                     last)           /* last entry to log */
1510{
1511        xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1512        xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1513        struct xfs_dir2_leaf    *leaf = bp->b_addr;
1514        struct xfs_dir2_leaf_entry *ents;
1515
1516        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1517               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1518               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1519               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1520
1521        ents = xfs_dir3_leaf_ents_p(leaf);
1522        firstlep = &ents[first];
1523        lastlep = &ents[last];
1524        xfs_trans_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1525                (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1526}
1527
1528/*
1529 * Log the header of the leaf1 or leafn block.
1530 */
1531void
1532xfs_dir3_leaf_log_header(
1533        struct xfs_trans        *tp,
1534        struct xfs_buf          *bp)
1535{
1536        struct xfs_dir2_leaf    *leaf = bp->b_addr;
1537
1538        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1539               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1540               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1541               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1542
1543        xfs_trans_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1544                          xfs_dir3_leaf_hdr_size(leaf) - 1);
1545}
1546
1547/*
1548 * Log the tail of the leaf1 block.
1549 */
1550STATIC void
1551xfs_dir3_leaf_log_tail(
1552        struct xfs_trans        *tp,
1553        struct xfs_buf          *bp)
1554{
1555        struct xfs_dir2_leaf    *leaf = bp->b_addr;
1556        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1557        struct xfs_mount        *mp = tp->t_mountp;
1558
1559        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1560               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1561               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1562               leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1563
1564        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1565        xfs_trans_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1566                (uint)(mp->m_dirblksize - 1));
1567}
1568
1569/*
1570 * Look up the entry referred to by args in the leaf format directory.
1571 * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1572 * is also used by the node-format code.
1573 */
1574int
1575xfs_dir2_leaf_lookup(
1576        xfs_da_args_t           *args)          /* operation arguments */
1577{
1578        struct xfs_buf          *dbp;           /* data block buffer */
1579        xfs_dir2_data_entry_t   *dep;           /* data block entry */
1580        xfs_inode_t             *dp;            /* incore directory inode */
1581        int                     error;          /* error return code */
1582        int                     index;          /* found entry index */
1583        struct xfs_buf          *lbp;           /* leaf buffer */
1584        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1585        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1586        xfs_trans_t             *tp;            /* transaction pointer */
1587        struct xfs_dir2_leaf_entry *ents;
1588
1589        trace_xfs_dir2_leaf_lookup(args);
1590
1591        /*
1592         * Look up name in the leaf block, returning both buffers and index.
1593         */
1594        if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1595                return error;
1596        }
1597        tp = args->trans;
1598        dp = args->dp;
1599        xfs_dir3_leaf_check(dp->i_mount, lbp);
1600        leaf = lbp->b_addr;
1601        ents = xfs_dir3_leaf_ents_p(leaf);
1602        /*
1603         * Get to the leaf entry and contained data entry address.
1604         */
1605        lep = &ents[index];
1606
1607        /*
1608         * Point to the data entry.
1609         */
1610        dep = (xfs_dir2_data_entry_t *)
1611              ((char *)dbp->b_addr +
1612               xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1613        /*
1614         * Return the found inode number & CI name if appropriate
1615         */
1616        args->inumber = be64_to_cpu(dep->inumber);
1617        error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1618        xfs_trans_brelse(tp, dbp);
1619        xfs_trans_brelse(tp, lbp);
1620        return XFS_ERROR(error);
1621}
1622
1623/*
1624 * Look up name/hash in the leaf block.
1625 * Fill in indexp with the found index, and dbpp with the data buffer.
1626 * If not found dbpp will be NULL, and ENOENT comes back.
1627 * lbpp will always be filled in with the leaf buffer unless there's an error.
1628 */
1629static int                                      /* error */
1630xfs_dir2_leaf_lookup_int(
1631        xfs_da_args_t           *args,          /* operation arguments */
1632        struct xfs_buf          **lbpp,         /* out: leaf buffer */
1633        int                     *indexp,        /* out: index in leaf block */
1634        struct xfs_buf          **dbpp)         /* out: data buffer */
1635{
1636        xfs_dir2_db_t           curdb = -1;     /* current data block number */
1637        struct xfs_buf          *dbp = NULL;    /* data buffer */
1638        xfs_dir2_data_entry_t   *dep;           /* data entry */
1639        xfs_inode_t             *dp;            /* incore directory inode */
1640        int                     error;          /* error return code */
1641        int                     index;          /* index in leaf block */
1642        struct xfs_buf          *lbp;           /* leaf buffer */
1643        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1644        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1645        xfs_mount_t             *mp;            /* filesystem mount point */
1646        xfs_dir2_db_t           newdb;          /* new data block number */
1647        xfs_trans_t             *tp;            /* transaction pointer */
1648        xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1649        enum xfs_dacmp          cmp;            /* name compare result */
1650        struct xfs_dir2_leaf_entry *ents;
1651        struct xfs_dir3_icleaf_hdr leafhdr;
1652
1653        dp = args->dp;
1654        tp = args->trans;
1655        mp = dp->i_mount;
1656
1657        error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
1658        if (error)
1659                return error;
1660
1661        *lbpp = lbp;
1662        leaf = lbp->b_addr;
1663        xfs_dir3_leaf_check(mp, lbp);
1664        ents = xfs_dir3_leaf_ents_p(leaf);
1665        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1666
1667        /*
1668         * Look for the first leaf entry with our hash value.
1669         */
1670        index = xfs_dir2_leaf_search_hash(args, lbp);
1671        /*
1672         * Loop over all the entries with the right hash value
1673         * looking to match the name.
1674         */
1675        for (lep = &ents[index];
1676             index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
1677             lep++, index++) {
1678                /*
1679                 * Skip over stale leaf entries.
1680                 */
1681                if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1682                        continue;
1683                /*
1684                 * Get the new data block number.
1685                 */
1686                newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1687                /*
1688                 * If it's not the same as the old data block number,
1689                 * need to pitch the old one and read the new one.
1690                 */
1691                if (newdb != curdb) {
1692                        if (dbp)
1693                                xfs_trans_brelse(tp, dbp);
1694                        error = xfs_dir3_data_read(tp, dp,
1695                                                   xfs_dir2_db_to_da(mp, newdb),
1696                                                   -1, &dbp);
1697                        if (error) {
1698                                xfs_trans_brelse(tp, lbp);
1699                                return error;
1700                        }
1701                        curdb = newdb;
1702                }
1703                /*
1704                 * Point to the data entry.
1705                 */
1706                dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1707                        xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1708                /*
1709                 * Compare name and if it's an exact match, return the index
1710                 * and buffer. If it's the first case-insensitive match, store
1711                 * the index and buffer and continue looking for an exact match.
1712                 */
1713                cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1714                if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1715                        args->cmpresult = cmp;
1716                        *indexp = index;
1717                        /* case exact match: return the current buffer. */
1718                        if (cmp == XFS_CMP_EXACT) {
1719                                *dbpp = dbp;
1720                                return 0;
1721                        }
1722                        cidb = curdb;
1723                }
1724        }
1725        ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1726        /*
1727         * Here, we can only be doing a lookup (not a rename or remove).
1728         * If a case-insensitive match was found earlier, re-read the
1729         * appropriate data block if required and return it.
1730         */
1731        if (args->cmpresult == XFS_CMP_CASE) {
1732                ASSERT(cidb != -1);
1733                if (cidb != curdb) {
1734                        xfs_trans_brelse(tp, dbp);
1735                        error = xfs_dir3_data_read(tp, dp,
1736                                                   xfs_dir2_db_to_da(mp, cidb),
1737                                                   -1, &dbp);
1738                        if (error) {
1739                                xfs_trans_brelse(tp, lbp);
1740                                return error;
1741                        }
1742                }
1743                *dbpp = dbp;
1744                return 0;
1745        }
1746        /*
1747         * No match found, return ENOENT.
1748         */
1749        ASSERT(cidb == -1);
1750        if (dbp)
1751                xfs_trans_brelse(tp, dbp);
1752        xfs_trans_brelse(tp, lbp);
1753        return XFS_ERROR(ENOENT);
1754}
1755
1756/*
1757 * Remove an entry from a leaf format directory.
1758 */
1759int                                             /* error */
1760xfs_dir2_leaf_removename(
1761        xfs_da_args_t           *args)          /* operation arguments */
1762{
1763        __be16                  *bestsp;        /* leaf block best freespace */
1764        xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1765        xfs_dir2_db_t           db;             /* data block number */
1766        struct xfs_buf          *dbp;           /* data block buffer */
1767        xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1768        xfs_inode_t             *dp;            /* incore directory inode */
1769        int                     error;          /* error return code */
1770        xfs_dir2_db_t           i;              /* temporary data block # */
1771        int                     index;          /* index into leaf entries */
1772        struct xfs_buf          *lbp;           /* leaf buffer */
1773        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1774        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1775        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1776        xfs_mount_t             *mp;            /* filesystem mount point */
1777        int                     needlog;        /* need to log data header */
1778        int                     needscan;       /* need to rescan data frees */
1779        xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1780        xfs_trans_t             *tp;            /* transaction pointer */
1781        struct xfs_dir2_data_free *bf;          /* bestfree table */
1782        struct xfs_dir2_leaf_entry *ents;
1783        struct xfs_dir3_icleaf_hdr leafhdr;
1784
1785        trace_xfs_dir2_leaf_removename(args);
1786
1787        /*
1788         * Lookup the leaf entry, get the leaf and data blocks read in.
1789         */
1790        if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1791                return error;
1792        }
1793        dp = args->dp;
1794        tp = args->trans;
1795        mp = dp->i_mount;
1796        leaf = lbp->b_addr;
1797        hdr = dbp->b_addr;
1798        xfs_dir3_data_check(dp, dbp);
1799        bf = xfs_dir3_data_bestfree_p(hdr);
1800        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1801        ents = xfs_dir3_leaf_ents_p(leaf);
1802        /*
1803         * Point to the leaf entry, use that to point to the data entry.
1804         */
1805        lep = &ents[index];
1806        db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1807        dep = (xfs_dir2_data_entry_t *)
1808              ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1809        needscan = needlog = 0;
1810        oldbest = be16_to_cpu(bf[0].length);
1811        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1812        bestsp = xfs_dir2_leaf_bests_p(ltp);
1813        ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1814        /*
1815         * Mark the former data entry unused.
1816         */
1817        xfs_dir2_data_make_free(tp, dbp,
1818                (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1819                xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1820        /*
1821         * We just mark the leaf entry stale by putting a null in it.
1822         */
1823        leafhdr.stale++;
1824        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1825        xfs_dir3_leaf_log_header(tp, lbp);
1826
1827        lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1828        xfs_dir3_leaf_log_ents(tp, lbp, index, index);
1829
1830        /*
1831         * Scan the freespace in the data block again if necessary,
1832         * log the data block header if necessary.
1833         */
1834        if (needscan)
1835                xfs_dir2_data_freescan(mp, hdr, &needlog);
1836        if (needlog)
1837                xfs_dir2_data_log_header(tp, dbp);
1838        /*
1839         * If the longest freespace in the data block has changed,
1840         * put the new value in the bests table and log that.
1841         */
1842        if (be16_to_cpu(bf[0].length) != oldbest) {
1843                bestsp[db] = bf[0].length;
1844                xfs_dir3_leaf_log_bests(tp, lbp, db, db);
1845        }
1846        xfs_dir3_data_check(dp, dbp);
1847        /*
1848         * If the data block is now empty then get rid of the data block.
1849         */
1850        if (be16_to_cpu(bf[0].length) ==
1851                        mp->m_dirblksize - xfs_dir3_data_entry_offset(hdr)) {
1852                ASSERT(db != mp->m_dirdatablk);
1853                if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1854                        /*
1855                         * Nope, can't get rid of it because it caused
1856                         * allocation of a bmap btree block to do so.
1857                         * Just go on, returning success, leaving the
1858                         * empty block in place.
1859                         */
1860                        if (error == ENOSPC && args->total == 0)
1861                                error = 0;
1862                        xfs_dir3_leaf_check(mp, lbp);
1863                        return error;
1864                }
1865                dbp = NULL;
1866                /*
1867                 * If this is the last data block then compact the
1868                 * bests table by getting rid of entries.
1869                 */
1870                if (db == be32_to_cpu(ltp->bestcount) - 1) {
1871                        /*
1872                         * Look for the last active entry (i).
1873                         */
1874                        for (i = db - 1; i > 0; i--) {
1875                                if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1876                                        break;
1877                        }
1878                        /*
1879                         * Copy the table down so inactive entries at the
1880                         * end are removed.
1881                         */
1882                        memmove(&bestsp[db - i], bestsp,
1883                                (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1884                        be32_add_cpu(&ltp->bestcount, -(db - i));
1885                        xfs_dir3_leaf_log_tail(tp, lbp);
1886                        xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1887                } else
1888                        bestsp[db] = cpu_to_be16(NULLDATAOFF);
1889        }
1890        /*
1891         * If the data block was not the first one, drop it.
1892         */
1893        else if (db != mp->m_dirdatablk)
1894                dbp = NULL;
1895
1896        xfs_dir3_leaf_check(mp, lbp);
1897        /*
1898         * See if we can convert to block form.
1899         */
1900        return xfs_dir2_leaf_to_block(args, lbp, dbp);
1901}
1902
1903/*
1904 * Replace the inode number in a leaf format directory entry.
1905 */
1906int                                             /* error */
1907xfs_dir2_leaf_replace(
1908        xfs_da_args_t           *args)          /* operation arguments */
1909{
1910        struct xfs_buf          *dbp;           /* data block buffer */
1911        xfs_dir2_data_entry_t   *dep;           /* data block entry */
1912        xfs_inode_t             *dp;            /* incore directory inode */
1913        int                     error;          /* error return code */
1914        int                     index;          /* index of leaf entry */
1915        struct xfs_buf          *lbp;           /* leaf buffer */
1916        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1917        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1918        xfs_trans_t             *tp;            /* transaction pointer */
1919        struct xfs_dir2_leaf_entry *ents;
1920
1921        trace_xfs_dir2_leaf_replace(args);
1922
1923        /*
1924         * Look up the entry.
1925         */
1926        if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1927                return error;
1928        }
1929        dp = args->dp;
1930        leaf = lbp->b_addr;
1931        ents = xfs_dir3_leaf_ents_p(leaf);
1932        /*
1933         * Point to the leaf entry, get data address from it.
1934         */
1935        lep = &ents[index];
1936        /*
1937         * Point to the data entry.
1938         */
1939        dep = (xfs_dir2_data_entry_t *)
1940              ((char *)dbp->b_addr +
1941               xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1942        ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1943        /*
1944         * Put the new inode number in, log it.
1945         */
1946        dep->inumber = cpu_to_be64(args->inumber);
1947        tp = args->trans;
1948        xfs_dir2_data_log_entry(tp, dbp, dep);
1949        xfs_dir3_leaf_check(dp->i_mount, lbp);
1950        xfs_trans_brelse(tp, lbp);
1951        return 0;
1952}
1953
1954/*
1955 * Return index in the leaf block (lbp) which is either the first
1956 * one with this hash value, or if there are none, the insert point
1957 * for that hash value.
1958 */
1959int                                             /* index value */
1960xfs_dir2_leaf_search_hash(
1961        xfs_da_args_t           *args,          /* operation arguments */
1962        struct xfs_buf          *lbp)           /* leaf buffer */
1963{
1964        xfs_dahash_t            hash=0;         /* hash from this entry */
1965        xfs_dahash_t            hashwant;       /* hash value looking for */
1966        int                     high;           /* high leaf index */
1967        int                     low;            /* low leaf index */
1968        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1969        xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1970        int                     mid=0;          /* current leaf index */
1971        struct xfs_dir2_leaf_entry *ents;
1972        struct xfs_dir3_icleaf_hdr leafhdr;
1973
1974        leaf = lbp->b_addr;
1975        ents = xfs_dir3_leaf_ents_p(leaf);
1976        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1977
1978#ifndef __KERNEL__
1979        if (!leafhdr.count)
1980                return 0;
1981#endif
1982        /*
1983         * Note, the table cannot be empty, so we have to go through the loop.
1984         * Binary search the leaf entries looking for our hash value.
1985         */
1986        for (lep = ents, low = 0, high = leafhdr.count - 1,
1987                hashwant = args->hashval;
1988             low <= high; ) {
1989                mid = (low + high) >> 1;
1990                if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1991                        break;
1992                if (hash < hashwant)
1993                        low = mid + 1;
1994                else
1995                        high = mid - 1;
1996        }
1997        /*
1998         * Found one, back up through all the equal hash values.
1999         */
2000        if (hash == hashwant) {
2001                while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
2002                        mid--;
2003                }
2004        }
2005        /*
2006         * Need to point to an entry higher than ours.
2007         */
2008        else if (hash < hashwant)
2009                mid++;
2010        return mid;
2011}
2012
2013/*
2014 * Trim off a trailing data block.  We know it's empty since the leaf
2015 * freespace table says so.
2016 */
2017int                                             /* error */
2018xfs_dir2_leaf_trim_data(
2019        xfs_da_args_t           *args,          /* operation arguments */
2020        struct xfs_buf          *lbp,           /* leaf buffer */
2021        xfs_dir2_db_t           db)             /* data block number */
2022{
2023        __be16                  *bestsp;        /* leaf bests table */
2024        struct xfs_buf          *dbp;           /* data block buffer */
2025        xfs_inode_t             *dp;            /* incore directory inode */
2026        int                     error;          /* error return value */
2027        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2028        xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
2029        xfs_mount_t             *mp;            /* filesystem mount point */
2030        xfs_trans_t             *tp;            /* transaction pointer */
2031
2032        dp = args->dp;
2033        mp = dp->i_mount;
2034        tp = args->trans;
2035        /*
2036         * Read the offending data block.  We need its buffer.
2037         */
2038        error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp);
2039        if (error)
2040                return error;
2041
2042        leaf = lbp->b_addr;
2043        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
2044
2045#ifdef DEBUG
2046{
2047        struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
2048        struct xfs_dir2_data_free *bf = xfs_dir3_data_bestfree_p(hdr);
2049
2050        ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
2051               hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
2052        ASSERT(be16_to_cpu(bf[0].length) ==
2053               mp->m_dirblksize - xfs_dir3_data_entry_offset(hdr));
2054        ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
2055}
2056#endif
2057
2058        /*
2059         * Get rid of the data block.
2060         */
2061        if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
2062                ASSERT(error != ENOSPC);
2063                xfs_trans_brelse(tp, dbp);
2064                return error;
2065        }
2066        /*
2067         * Eliminate the last bests entry from the table.
2068         */
2069        bestsp = xfs_dir2_leaf_bests_p(ltp);
2070        be32_add_cpu(&ltp->bestcount, -1);
2071        memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
2072        xfs_dir3_leaf_log_tail(tp, lbp);
2073        xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
2074        return 0;
2075}
2076
2077static inline size_t
2078xfs_dir3_leaf_size(
2079        struct xfs_dir3_icleaf_hdr      *hdr,
2080        int                             counts)
2081{
2082        int     entries;
2083        int     hdrsize;
2084
2085        entries = hdr->count - hdr->stale;
2086        if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
2087            hdr->magic == XFS_DIR2_LEAFN_MAGIC)
2088                hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
2089        else
2090                hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
2091
2092        return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
2093                       + counts * sizeof(xfs_dir2_data_off_t)
2094                       + sizeof(xfs_dir2_leaf_tail_t);
2095}
2096
2097/*
2098 * Convert node form directory to leaf form directory.
2099 * The root of the node form dir needs to already be a LEAFN block.
2100 * Just return if we can't do anything.
2101 */
2102int                                             /* error */
2103xfs_dir2_node_to_leaf(
2104        xfs_da_state_t          *state)         /* directory operation state */
2105{
2106        xfs_da_args_t           *args;          /* operation arguments */
2107        xfs_inode_t             *dp;            /* incore directory inode */
2108        int                     error;          /* error return code */
2109        struct xfs_buf          *fbp;           /* buffer for freespace block */
2110        xfs_fileoff_t           fo;             /* freespace file offset */
2111        xfs_dir2_free_t         *free;          /* freespace structure */
2112        struct xfs_buf          *lbp;           /* buffer for leaf block */
2113        xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
2114        xfs_dir2_leaf_t         *leaf;          /* leaf structure */
2115        xfs_mount_t             *mp;            /* filesystem mount point */
2116        int                     rval;           /* successful free trim? */
2117        xfs_trans_t             *tp;            /* transaction pointer */
2118        struct xfs_dir3_icleaf_hdr leafhdr;
2119        struct xfs_dir3_icfree_hdr freehdr;
2120
2121        /*
2122         * There's more than a leaf level in the btree, so there must
2123         * be multiple leafn blocks.  Give up.
2124         */
2125        if (state->path.active > 1)
2126                return 0;
2127        args = state->args;
2128
2129        trace_xfs_dir2_node_to_leaf(args);
2130
2131        mp = state->mp;
2132        dp = args->dp;
2133        tp = args->trans;
2134        /*
2135         * Get the last offset in the file.
2136         */
2137        if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
2138                return error;
2139        }
2140        fo -= mp->m_dirblkfsbs;
2141        /*
2142         * If there are freespace blocks other than the first one,
2143         * take this opportunity to remove trailing empty freespace blocks
2144         * that may have been left behind during no-space-reservation
2145         * operations.
2146         */
2147        while (fo > mp->m_dirfreeblk) {
2148                if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
2149                        return error;
2150                }
2151                if (rval)
2152                        fo -= mp->m_dirblkfsbs;
2153                else
2154                        return 0;
2155        }
2156        /*
2157         * Now find the block just before the freespace block.
2158         */
2159        if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
2160                return error;
2161        }
2162        /*
2163         * If it's not the single leaf block, give up.
2164         */
2165        if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
2166                return 0;
2167        lbp = state->path.blk[0].bp;
2168        leaf = lbp->b_addr;
2169        xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
2170
2171        ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
2172               leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
2173
2174        /*
2175         * Read the freespace block.
2176         */
2177        error = xfs_dir2_free_read(tp, dp,  mp->m_dirfreeblk, &fbp);
2178        if (error)
2179                return error;
2180        free = fbp->b_addr;
2181        xfs_dir3_free_hdr_from_disk(&freehdr, free);
2182
2183        ASSERT(!freehdr.firstdb);
2184
2185        /*
2186         * Now see if the leafn and free data will fit in a leaf1.
2187         * If not, release the buffer and give up.
2188         */
2189        if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > mp->m_dirblksize) {
2190                xfs_trans_brelse(tp, fbp);
2191                return 0;
2192        }
2193
2194        /*
2195         * If the leaf has any stale entries in it, compress them out.
2196         */
2197        if (leafhdr.stale)
2198                xfs_dir3_leaf_compact(args, &leafhdr, lbp);
2199
2200        lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
2201        xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
2202        leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
2203                                        ? XFS_DIR2_LEAF1_MAGIC
2204                                        : XFS_DIR3_LEAF1_MAGIC;
2205
2206        /*
2207         * Set up the leaf tail from the freespace block.
2208         */
2209        ltp = xfs_dir2_leaf_tail_p(mp, leaf);
2210        ltp->bestcount = cpu_to_be32(freehdr.nvalid);
2211
2212        /*
2213         * Set up the leaf bests table.
2214         */
2215        memcpy(xfs_dir2_leaf_bests_p(ltp), xfs_dir3_free_bests_p(mp, free),
2216                freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
2217
2218        xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
2219        xfs_dir3_leaf_log_header(tp, lbp);
2220        xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
2221        xfs_dir3_leaf_log_tail(tp, lbp);
2222        xfs_dir3_leaf_check(mp, lbp);
2223
2224        /*
2225         * Get rid of the freespace block.
2226         */
2227        error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
2228        if (error) {
2229                /*
2230                 * This can't fail here because it can only happen when
2231                 * punching out the middle of an extent, and this is an
2232                 * isolated block.
2233                 */
2234                ASSERT(error != ENOSPC);
2235                return error;
2236        }
2237        fbp = NULL;
2238        /*
2239         * Now see if we can convert the single-leaf directory
2240         * down to a block form directory.
2241         * This routine always kills the dabuf for the leaf, so
2242         * eliminate it from the path.
2243         */
2244        error = xfs_dir2_leaf_to_block(args, lbp, NULL);
2245        state->path.blk[0].bp = NULL;
2246        return error;
2247}
2248
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