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   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * dir.c
   5  *
   6  * Creates, reads, walks and deletes directory-nodes
   7  *
   8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   9  *
  10  *  Portions of this code from linux/fs/ext3/dir.c
  11  *
  12  *  Copyright (C) 1992, 1993, 1994, 1995
  13  *  Remy Card (card@masi.ibp.fr)
  14  *  Laboratoire MASI - Institut Blaise pascal
  15  *  Universite Pierre et Marie Curie (Paris VI)
  16  *
  17  *   from
  18  *
  19  *   linux/fs/minix/dir.c
  20  *
  21  *   Copyright (C) 1991, 1992 Linux Torvalds
  22  *
  23  * This program is free software; you can redistribute it and/or
  24  * modify it under the terms of the GNU General Public
  25  * License as published by the Free Software Foundation; either
  26  * version 2 of the License, or (at your option) any later version.
  27  *
  28  * This program is distributed in the hope that it will be useful,
  29  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  30  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  31  * General Public License for more details.
  32  *
  33  * You should have received a copy of the GNU General Public
  34  * License along with this program; if not, write to the
  35  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  36  * Boston, MA 021110-1307, USA.
  37  */
  38
  39 #include <linux/fs.h>
  40 #include <linux/types.h>
  41 #include <linux/slab.h>
  42 #include <linux/highmem.h>
  43 #include <linux/quotaops.h>
  44
  45 #define MLOG_MASK_PREFIX ML_NAMEI
  46 #include <cluster/masklog.h>
  47
  48 #include "ocfs2.h"
  49
  50 #include "alloc.h"
  51 #include "blockcheck.h"
  52 #include "dir.h"
  53 #include "dlmglue.h"
  54 #include "extent_map.h"
  55 #include "file.h"
  56 #include "inode.h"
  57 #include "journal.h"
  58 #include "namei.h"
  59 #include "suballoc.h"
  60 #include "super.h"
  61 #include "uptodate.h"
  62
  63 #include "buffer_head_io.h"
  64
  65 #define NAMEI_RA_CHUNKS  2
  66 #define NAMEI_RA_BLOCKS  4
  67 #define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
  68 #define NAMEI_RA_INDEX(c,b)  (((c) * NAMEI_RA_BLOCKS) + (b))
  69
  70 static unsigned char ocfs2_filetype_table[] = {
  71         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
  72 };
  73
  74 static int ocfs2_extend_dir(struct ocfs2_super *osb,
  75                             struct inode *dir,
  76                             struct buffer_head *parent_fe_bh,
  77                             unsigned int blocks_wanted,
  78                             struct buffer_head **new_de_bh);
  79 static int ocfs2_do_extend_dir(struct super_block *sb,
  80                                handle_t *handle,
  81                                struct inode *dir,
  82                                struct buffer_head *parent_fe_bh,
  83                                struct ocfs2_alloc_context *data_ac,
  84                                struct ocfs2_alloc_context *meta_ac,
  85                                struct buffer_head **new_bh);
  86
  87 /*
  88  * These are distinct checks because future versions of the file system will
  89  * want to have a trailing dirent structure independent of indexing.
  90  */
  91 static int ocfs2_dir_has_trailer(struct inode *dir)
  92 {
  93         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
  94                 return 0;
  95
  96         return ocfs2_meta_ecc(OCFS2_SB(dir->i_sb));
  97 }
  98
  99 static int ocfs2_supports_dir_trailer(struct ocfs2_super *osb)
 100 {
 101         return ocfs2_meta_ecc(osb);
 102 }
 103
 104 static inline unsigned int ocfs2_dir_trailer_blk_off(struct super_block *sb)
 105 {
 106         return sb->s_blocksize - sizeof(struct ocfs2_dir_block_trailer);
 107 }
 108
 109 #define ocfs2_trailer_from_bh(_bh, _sb) ((struct ocfs2_dir_block_trailer *) ((_bh)->b_data + ocfs2_dir_trailer_blk_off((_sb))))
 110
 111 /* XXX ocfs2_block_dqtrailer() is similar but not quite - can we make
 112  * them more consistent? */
 113 struct ocfs2_dir_block_trailer *ocfs2_dir_trailer_from_size(int blocksize,
 114                                                             void *data)
 115 {
 116         char *p = data;
 117
 118         p += blocksize - sizeof(struct ocfs2_dir_block_trailer);
 119         return (struct ocfs2_dir_block_trailer *)p;
 120 }
 121
 122 /*
 123  * XXX: This is executed once on every dirent. We should consider optimizing
 124  * it.
 125  */
 126 static int ocfs2_skip_dir_trailer(struct inode *dir,
 127                                   struct ocfs2_dir_entry *de,
 128                                   unsigned long offset,
 129                                   unsigned long blklen)
 130 {
 131         unsigned long toff = blklen - sizeof(struct ocfs2_dir_block_trailer);
 132
 133         if (!ocfs2_dir_has_trailer(dir))
 134                 return 0;
 135
 136         if (offset != toff)
 137                 return 0;
 138
 139         return 1;
 140 }
 141
 142 static void ocfs2_init_dir_trailer(struct inode *inode,
 143                                    struct buffer_head *bh)
 144 {
 145         struct ocfs2_dir_block_trailer *trailer;
 146
 147         trailer = ocfs2_trailer_from_bh(bh, inode->i_sb);
 148         strcpy(trailer->db_signature, OCFS2_DIR_TRAILER_SIGNATURE);
 149         trailer->db_compat_rec_len =
 150                         cpu_to_le16(sizeof(struct ocfs2_dir_block_trailer));
 151         trailer->db_parent_dinode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
 152         trailer->db_blkno = cpu_to_le64(bh->b_blocknr);
 153 }
 154
 155 /*
 156  * bh passed here can be an inode block or a dir data block, depending
 157  * on the inode inline data flag.
 158  */
 159 static int ocfs2_check_dir_entry(struct inode * dir,
 160                                  struct ocfs2_dir_entry * de,
 161                                  struct buffer_head * bh,
 162                                  unsigned long offset)
 163 {
 164         const char *error_msg = NULL;
 165         const int rlen = le16_to_cpu(de->rec_len);
 166
 167         if (rlen < OCFS2_DIR_REC_LEN(1))
 168                 error_msg = "rec_len is smaller than minimal";
 169         else if (rlen % 4 != 0)
 170                 error_msg = "rec_len % 4 != 0";
 171         else if (rlen < OCFS2_DIR_REC_LEN(de->name_len))
 172                 error_msg = "rec_len is too small for name_len";
 173         else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
 174                 error_msg = "directory entry across blocks";
 175
 176         if (error_msg != NULL)
 177                 mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
 178                      "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
 179                      (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
 180                      offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
 181                      de->name_len);
 182         return error_msg == NULL ? 1 : 0;
 183 }
 184
 185 static inline int ocfs2_match(int len,
 186                               const char * const name,
 187                               struct ocfs2_dir_entry *de)
 188 {
 189         if (len != de->name_len)
 190                 return 0;
 191         if (!de->inode)
 192                 return 0;
 193         return !memcmp(name, de->name, len);
 194 }
 195
 196 /*
 197  * Returns 0 if not found, -1 on failure, and 1 on success
 198  */
 199 static int inline ocfs2_search_dirblock(struct buffer_head *bh,
 200                                         struct inode *dir,
 201                                         const char *name, int namelen,
 202                                         unsigned long offset,
 203                                         char *first_de,
 204                                         unsigned int bytes,
 205                                         struct ocfs2_dir_entry **res_dir)
 206 {
 207         struct ocfs2_dir_entry *de;
 208         char *dlimit, *de_buf;
 209         int de_len;
 210         int ret = 0;
 211
 212         mlog_entry_void();
 213
 214         de_buf = first_de;
 215         dlimit = de_buf + bytes;
 216
 217         while (de_buf < dlimit) {
 218                 /* this code is executed quadratically often */
 219                 /* do minimal checking `by hand' */
 220
 221                 de = (struct ocfs2_dir_entry *) de_buf;
 222
 223                 if (de_buf + namelen <= dlimit &&
 224                     ocfs2_match(namelen, name, de)) {
 225                         /* found a match - just to be sure, do a full check */
 226                         if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
 227                                 ret = -1;
 228                                 goto bail;
 229                         }
 230                         *res_dir = de;
 231                         ret = 1;
 232                         goto bail;
 233                 }
 234
 235                 /* prevent looping on a bad block */
 236                 de_len = le16_to_cpu(de->rec_len);
 237                 if (de_len <= 0) {
 238                         ret = -1;
 239                         goto bail;
 240                 }
 241
 242                 de_buf += de_len;
 243                 offset += de_len;
 244         }
 245
 246 bail:
 247         mlog_exit(ret);
 248         return ret;
 249 }
 250
 251 static struct buffer_head *ocfs2_find_entry_id(const char *name,
 252                                                int namelen,
 253                                                struct inode *dir,
 254                                                struct ocfs2_dir_entry **res_dir)
 255 {
 256         int ret, found;
 257         struct buffer_head *di_bh = NULL;
 258         struct ocfs2_dinode *di;
 259         struct ocfs2_inline_data *data;
 260
 261         ret = ocfs2_read_inode_block(dir, &di_bh);
 262         if (ret) {
 263                 mlog_errno(ret);
 264                 goto out;
 265         }
 266
 267         di = (struct ocfs2_dinode *)di_bh->b_data;
 268         data = &di->id2.i_data;
 269
 270         found = ocfs2_search_dirblock(di_bh, dir, name, namelen, 0,
 271                                       data->id_data, i_size_read(dir), res_dir);
 272         if (found == 1)
 273                 return di_bh;
 274
 275         brelse(di_bh);
 276 out:
 277         return NULL;
 278 }
 279
 280 static int ocfs2_validate_dir_block(struct super_block *sb,
 281                                     struct buffer_head *bh)
 282 {
 283         int rc;
 284         struct ocfs2_dir_block_trailer *trailer =
 285                 ocfs2_trailer_from_bh(bh, sb);
 286
 287
 288         /*
 289          * We don't validate dirents here, that's handled
 290          * in-place when the code walks them.
 291          */
 292         mlog(0, "Validating dirblock %llu\n",
 293              (unsigned long long)bh->b_blocknr);
 294
 295         BUG_ON(!buffer_uptodate(bh));
 296
 297         /*
 298          * If the ecc fails, we return the error but otherwise
 299          * leave the filesystem running.  We know any error is
 300          * local to this block.
 301          *
 302          * Note that we are safe to call this even if the directory
 303          * doesn't have a trailer.  Filesystems without metaecc will do
 304          * nothing, and filesystems with it will have one.
 305          */
 306         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &trailer->db_check);
 307         if (rc)
 308                 mlog(ML_ERROR, "Checksum failed for dinode %llu\n",
 309                      (unsigned long long)bh->b_blocknr);
 310
 311         return rc;
 312 }
 313
 314 /*
 315  * This function forces all errors to -EIO for consistency with its
 316  * predecessor, ocfs2_bread().  We haven't audited what returning the
 317  * real error codes would do to callers.  We log the real codes with
 318  * mlog_errno() before we squash them.
 319  */
 320 static int ocfs2_read_dir_block(struct inode *inode, u64 v_block,
 321                                 struct buffer_head **bh, int flags)
 322 {
 323         int rc = 0;
 324         struct buffer_head *tmp = *bh;
 325         struct ocfs2_dir_block_trailer *trailer;
 326
 327         rc = ocfs2_read_virt_blocks(inode, v_block, 1, &tmp, flags,
 328                                     ocfs2_validate_dir_block);
 329         if (rc) {
 330                 mlog_errno(rc);
 331                 goto out;
 332         }
 333
 334         /*
 335          * We check the trailer here rather than in
 336          * ocfs2_validate_dir_block() because that function doesn't have
 337          * the inode to test.
 338          */
 339         if (!(flags & OCFS2_BH_READAHEAD) &&
 340             ocfs2_dir_has_trailer(inode)) {
 341                 trailer = ocfs2_trailer_from_bh(tmp, inode->i_sb);
 342                 if (!OCFS2_IS_VALID_DIR_TRAILER(trailer)) {
 343                         rc = -EINVAL;
 344                         ocfs2_error(inode->i_sb,
 345                                     "Invalid dirblock #%llu: "
 346                                     "signature = %.*s\n",
 347                                     (unsigned long long)tmp->b_blocknr, 7,
 348                                     trailer->db_signature);
 349                         goto out;
 350                 }
 351                 if (le64_to_cpu(trailer->db_blkno) != tmp->b_blocknr) {
 352                         rc = -EINVAL;
 353                         ocfs2_error(inode->i_sb,
 354                                     "Directory block #%llu has an invalid "
 355                                     "db_blkno of %llu",
 356                                     (unsigned long long)tmp->b_blocknr,
 357                                     (unsigned long long)le64_to_cpu(trailer->db_blkno));
 358                         goto out;
 359                 }
 360                 if (le64_to_cpu(trailer->db_parent_dinode) !=
 361                     OCFS2_I(inode)->ip_blkno) {
 362                         rc = -EINVAL;
 363                         ocfs2_error(inode->i_sb,
 364                                     "Directory block #%llu on dinode "
 365                                     "#%llu has an invalid parent_dinode "
 366                                     "of %llu",
 367                                     (unsigned long long)tmp->b_blocknr,
 368                                     (unsigned long long)OCFS2_I(inode)->ip_blkno,
 369                                     (unsigned long long)le64_to_cpu(trailer->db_blkno));
 370                         goto out;
 371                 }
 372         }
 373
 374         /* If ocfs2_read_virt_blocks() got us a new bh, pass it up. */
 375         if (!*bh)
 376                 *bh = tmp;
 377
 378 out:
 379         return rc ? -EIO : 0;
 380 }
 381
 382 static struct buffer_head *ocfs2_find_entry_el(const char *name, int namelen,
 383                                                struct inode *dir,
 384                                                struct ocfs2_dir_entry **res_dir)
 385 {
 386         struct super_block *sb;
 387         struct buffer_head *bh_use[NAMEI_RA_SIZE];
 388         struct buffer_head *bh, *ret = NULL;
 389         unsigned long start, block, b;
 390         int ra_max = 0;         /* Number of bh's in the readahead
 391                                    buffer, bh_use[] */
 392         int ra_ptr = 0;         /* Current index into readahead
 393                                    buffer */
 394         int num = 0;
 395         int nblocks, i, err;
 396
 397         mlog_entry_void();
 398
 399         sb = dir->i_sb;
 400
 401         nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
 402         start = OCFS2_I(dir)->ip_dir_start_lookup;
 403         if (start >= nblocks)
 404                 start = 0;
 405         block = start;
 406
 407 restart:
 408         do {
 409                 /*
 410                  * We deal with the read-ahead logic here.
 411                  */
 412                 if (ra_ptr >= ra_max) {
 413                         /* Refill the readahead buffer */
 414                         ra_ptr = 0;
 415                         b = block;
 416                         for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
 417                                 /*
 418                                  * Terminate if we reach the end of the
 419                                  * directory and must wrap, or if our
 420                                  * search has finished at this block.
 421                                  */
 422                                 if (b >= nblocks || (num && block == start)) {
 423                                         bh_use[ra_max] = NULL;
 424                                         break;
 425                                 }
 426                                 num++;
 427
 428                                 bh = NULL;
 429                                 err = ocfs2_read_dir_block(dir, b++, &bh,
 430                                                            OCFS2_BH_READAHEAD);
 431                                 bh_use[ra_max] = bh;
 432                         }
 433                 }
 434                 if ((bh = bh_use[ra_ptr++]) == NULL)
 435                         goto next;
 436                 if (ocfs2_read_dir_block(dir, block, &bh, 0)) {
 437                         /* read error, skip block & hope for the best.
 438                          * ocfs2_read_dir_block() has released the bh. */
 439                         ocfs2_error(dir->i_sb, "reading directory %llu, "
 440                                     "offset %lu\n",
 441                                     (unsigned long long)OCFS2_I(dir)->ip_blkno,
 442                                     block);
 443                         goto next;
 444                 }
 445                 i = ocfs2_search_dirblock(bh, dir, name, namelen,
 446                                           block << sb->s_blocksize_bits,
 447                                           bh->b_data, sb->s_blocksize,
 448                                           res_dir);
 449                 if (i == 1) {
 450                         OCFS2_I(dir)->ip_dir_start_lookup = block;
 451                         ret = bh;
 452                         goto cleanup_and_exit;
 453                 } else {
 454                         brelse(bh);
 455                         if (i < 0)
 456                                 goto cleanup_and_exit;
 457                 }
 458         next:
 459                 if (++block >= nblocks)
 460                         block = 0;
 461         } while (block != start);
 462
 463         /*
 464          * If the directory has grown while we were searching, then
 465          * search the last part of the directory before giving up.
 466          */
 467         block = nblocks;
 468         nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
 469         if (block < nblocks) {
 470                 start = 0;
 471                 goto restart;
 472         }
 473
 474 cleanup_and_exit:
 475         /* Clean up the read-ahead blocks */
 476         for (; ra_ptr < ra_max; ra_ptr++)
 477                 brelse(bh_use[ra_ptr]);
 478
 479         mlog_exit_ptr(ret);
 480         return ret;
 481 }
 482
 483 /*
 484  * Try to find an entry of the provided name within 'dir'.
 485  *
 486  * If nothing was found, NULL is returned. Otherwise, a buffer_head
 487  * and pointer to the dir entry are passed back.
 488  *
 489  * Caller can NOT assume anything about the contents of the
 490  * buffer_head - it is passed back only so that it can be passed into
 491  * any one of the manipulation functions (add entry, delete entry,
 492  * etc). As an example, bh in the extent directory case is a data
 493  * block, in the inline-data case it actually points to an inode.
 494  */
 495 struct buffer_head *ocfs2_find_entry(const char *name, int namelen,
 496                                      struct inode *dir,
 497                                      struct ocfs2_dir_entry **res_dir)
 498 {
 499         *res_dir = NULL;
 500
 501         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 502                 return ocfs2_find_entry_id(name, namelen, dir, res_dir);
 503
 504         return ocfs2_find_entry_el(name, namelen, dir, res_dir);
 505 }
 506
 507 /*
 508  * Update inode number and type of a previously found directory entry.
 509  */
 510 int ocfs2_update_entry(struct inode *dir, handle_t *handle,
 511                        struct buffer_head *de_bh, struct ocfs2_dir_entry *de,
 512                        struct inode *new_entry_inode)
 513 {
 514         int ret;
 515         ocfs2_journal_access_func access = ocfs2_journal_access_db;
 516
 517         /*
 518          * The same code works fine for both inline-data and extent
 519          * based directories, so no need to split this up.  The only
 520          * difference is the journal_access function.
 521          */
 522
 523         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 524                 access = ocfs2_journal_access_di;
 525
 526         ret = access(handle, dir, de_bh, OCFS2_JOURNAL_ACCESS_WRITE);
 527         if (ret) {
 528                 mlog_errno(ret);
 529                 goto out;
 530         }
 531
 532         de->inode = cpu_to_le64(OCFS2_I(new_entry_inode)->ip_blkno);
 533         ocfs2_set_de_type(de, new_entry_inode->i_mode);
 534
 535         ocfs2_journal_dirty(handle, de_bh);
 536
 537 out:
 538         return ret;
 539 }
 540
 541 static int __ocfs2_delete_entry(handle_t *handle, struct inode *dir,
 542                                 struct ocfs2_dir_entry *de_del,
 543                                 struct buffer_head *bh, char *first_de,
 544                                 unsigned int bytes)
 545 {
 546         struct ocfs2_dir_entry *de, *pde;
 547         int i, status = -ENOENT;
 548         ocfs2_journal_access_func access = ocfs2_journal_access_db;
 549
 550         mlog_entry("(0x%p, 0x%p, 0x%p, 0x%p)\n", handle, dir, de_del, bh);
 551
 552         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 553                 access = ocfs2_journal_access_di;
 554
 555         i = 0;
 556         pde = NULL;
 557         de = (struct ocfs2_dir_entry *) first_de;
 558         while (i < bytes) {
 559                 if (!ocfs2_check_dir_entry(dir, de, bh, i)) {
 560                         status = -EIO;
 561                         mlog_errno(status);
 562                         goto bail;
 563                 }
 564                 if (de == de_del)  {
 565                         status = access(handle, dir, bh,
 566                                         OCFS2_JOURNAL_ACCESS_WRITE);
 567                         if (status < 0) {
 568                                 status = -EIO;
 569                                 mlog_errno(status);
 570                                 goto bail;
 571                         }
 572                         if (pde)
 573                                 le16_add_cpu(&pde->rec_len,
 574                                                 le16_to_cpu(de->rec_len));
 575                         else
 576                                 de->inode = 0;
 577                         dir->i_version++;
 578                         status = ocfs2_journal_dirty(handle, bh);
 579                         goto bail;
 580                 }
 581                 i += le16_to_cpu(de->rec_len);
 582                 pde = de;
 583                 de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
 584         }
 585 bail:
 586         mlog_exit(status);
 587         return status;
 588 }
 589
 590 static inline int ocfs2_delete_entry_id(handle_t *handle,
 591                                         struct inode *dir,
 592                                         struct ocfs2_dir_entry *de_del,
 593                                         struct buffer_head *bh)
 594 {
 595         int ret;
 596         struct buffer_head *di_bh = NULL;
 597         struct ocfs2_dinode *di;
 598         struct ocfs2_inline_data *data;
 599
 600         ret = ocfs2_read_inode_block(dir, &di_bh);
 601         if (ret) {
 602                 mlog_errno(ret);
 603                 goto out;
 604         }
 605
 606         di = (struct ocfs2_dinode *)di_bh->b_data;
 607         data = &di->id2.i_data;
 608
 609         ret = __ocfs2_delete_entry(handle, dir, de_del, bh, data->id_data,
 610                                    i_size_read(dir));
 611
 612         brelse(di_bh);
 613 out:
 614         return ret;
 615 }
 616
 617 static inline int ocfs2_delete_entry_el(handle_t *handle,
 618                                         struct inode *dir,
 619                                         struct ocfs2_dir_entry *de_del,
 620                                         struct buffer_head *bh)
 621 {
 622         return __ocfs2_delete_entry(handle, dir, de_del, bh, bh->b_data,
 623                                     bh->b_size);
 624 }
 625
 626 /*
 627  * ocfs2_delete_entry deletes a directory entry by merging it with the
 628  * previous entry
 629  */
 630 int ocfs2_delete_entry(handle_t *handle,
 631                        struct inode *dir,
 632                        struct ocfs2_dir_entry *de_del,
 633                        struct buffer_head *bh)
 634 {
 635         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 636                 return ocfs2_delete_entry_id(handle, dir, de_del, bh);
 637
 638         return ocfs2_delete_entry_el(handle, dir, de_del, bh);
 639 }
 640
 641 /*
 642  * Check whether 'de' has enough room to hold an entry of
 643  * 'new_rec_len' bytes.
 644  */
 645 static inline int ocfs2_dirent_would_fit(struct ocfs2_dir_entry *de,
 646                                          unsigned int new_rec_len)
 647 {
 648         unsigned int de_really_used;
 649
 650         /* Check whether this is an empty record with enough space */
 651         if (le64_to_cpu(de->inode) == 0 &&
 652             le16_to_cpu(de->rec_len) >= new_rec_len)
 653                 return 1;
 654
 655         /*
 656          * Record might have free space at the end which we can
 657          * use.
 658          */
 659         de_really_used = OCFS2_DIR_REC_LEN(de->name_len);
 660         if (le16_to_cpu(de->rec_len) >= (de_really_used + new_rec_len))
 661             return 1;
 662
 663         return 0;
 664 }
 665
 666 /* we don't always have a dentry for what we want to add, so people
 667  * like orphan dir can call this instead.
 668  *
 669  * If you pass me insert_bh, I'll skip the search of the other dir
 670  * blocks and put the record in there.
 671  */
 672 int __ocfs2_add_entry(handle_t *handle,
 673                       struct inode *dir,
 674                       const char *name, int namelen,
 675                       struct inode *inode, u64 blkno,
 676                       struct buffer_head *parent_fe_bh,
 677                       struct buffer_head *insert_bh)
 678 {
 679         unsigned long offset;
 680         unsigned short rec_len;
 681         struct ocfs2_dir_entry *de, *de1;
 682         struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
 683         struct super_block *sb = dir->i_sb;
 684         int retval, status;
 685         unsigned int size = sb->s_blocksize;
 686         char *data_start = insert_bh->b_data;
 687
 688         mlog_entry_void();
 689
 690         if (!namelen)
 691                 return -EINVAL;
 692
 693         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
 694                 data_start = di->id2.i_data.id_data;
 695                 size = i_size_read(dir);
 696
 697                 BUG_ON(insert_bh != parent_fe_bh);
 698         }
 699
 700         rec_len = OCFS2_DIR_REC_LEN(namelen);
 701         offset = 0;
 702         de = (struct ocfs2_dir_entry *) data_start;
 703         while (1) {
 704                 BUG_ON((char *)de >= (size + data_start));
 705
 706                 /* These checks should've already been passed by the
 707                  * prepare function, but I guess we can leave them
 708                  * here anyway. */
 709                 if (!ocfs2_check_dir_entry(dir, de, insert_bh, offset)) {
 710                         retval = -ENOENT;
 711                         goto bail;
 712                 }
 713                 if (ocfs2_match(namelen, name, de)) {
 714                         retval = -EEXIST;
 715                         goto bail;
 716                 }
 717
 718                 /* We're guaranteed that we should have space, so we
 719                  * can't possibly have hit the trailer...right? */
 720                 mlog_bug_on_msg(ocfs2_skip_dir_trailer(dir, de, offset, size),
 721                                 "Hit dir trailer trying to insert %.*s "
 722                                 "(namelen %d) into directory %llu.  "
 723                                 "offset is %lu, trailer offset is %d\n",
 724                                 namelen, name, namelen,
 725                                 (unsigned long long)parent_fe_bh->b_blocknr,
 726                                 offset, ocfs2_dir_trailer_blk_off(dir->i_sb));
 727
 728                 if (ocfs2_dirent_would_fit(de, rec_len)) {
 729                         dir->i_mtime = dir->i_ctime = CURRENT_TIME;
 730                         retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
 731                         if (retval < 0) {
 732                                 mlog_errno(retval);
 733                                 goto bail;
 734                         }
 735
 736                         if (insert_bh == parent_fe_bh)
 737                                 status = ocfs2_journal_access_di(handle, dir,
 738                                                                  insert_bh,
 739                                                                  OCFS2_JOURNAL_ACCESS_WRITE);
 740                         else
 741                                 status = ocfs2_journal_access_db(handle, dir,
 742                                                                  insert_bh,
 743                                                                  OCFS2_JOURNAL_ACCESS_WRITE);
 744                         /* By now the buffer is marked for journaling */
 745                         offset += le16_to_cpu(de->rec_len);
 746                         if (le64_to_cpu(de->inode)) {
 747                                 de1 = (struct ocfs2_dir_entry *)((char *) de +
 748                                         OCFS2_DIR_REC_LEN(de->name_len));
 749                                 de1->rec_len =
 750                                         cpu_to_le16(le16_to_cpu(de->rec_len) -
 751                                         OCFS2_DIR_REC_LEN(de->name_len));
 752                                 de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
 753                                 de = de1;
 754                         }
 755                         de->file_type = OCFS2_FT_UNKNOWN;
 756                         if (blkno) {
 757                                 de->inode = cpu_to_le64(blkno);
 758                                 ocfs2_set_de_type(de, inode->i_mode);
 759                         } else
 760                                 de->inode = 0;
 761                         de->name_len = namelen;
 762                         memcpy(de->name, name, namelen);
 763
 764                         dir->i_version++;
 765                         status = ocfs2_journal_dirty(handle, insert_bh);
 766                         retval = 0;
 767                         goto bail;
 768                 }
 769
 770                 offset += le16_to_cpu(de->rec_len);
 771                 de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
 772         }
 773
 774         /* when you think about it, the assert above should prevent us
 775          * from ever getting here. */
 776         retval = -ENOSPC;
 777 bail:
 778
 779         mlog_exit(retval);
 780         return retval;
 781 }
 782
 783 static int ocfs2_dir_foreach_blk_id(struct inode *inode,
 784                                     u64 *f_version,
 785                                     loff_t *f_pos, void *priv,
 786                                     filldir_t filldir, int *filldir_err)
 787 {
 788         int ret, i, filldir_ret;
 789         unsigned long offset = *f_pos;
 790         struct buffer_head *di_bh = NULL;
 791         struct ocfs2_dinode *di;
 792         struct ocfs2_inline_data *data;
 793         struct ocfs2_dir_entry *de;
 794
 795         ret = ocfs2_read_inode_block(inode, &di_bh);
 796         if (ret) {
 797                 mlog(ML_ERROR, "Unable to read inode block for dir %llu\n",
 798                      (unsigned long long)OCFS2_I(inode)->ip_blkno);
 799                 goto out;
 800         }
 801
 802         di = (struct ocfs2_dinode *)di_bh->b_data;
 803         data = &di->id2.i_data;
 804
 805         while (*f_pos < i_size_read(inode)) {
 806 revalidate:
 807                 /* If the dir block has changed since the last call to
 808                  * readdir(2), then we might be pointing to an invalid
 809                  * dirent right now.  Scan from the start of the block
 810                  * to make sure. */
 811                 if (*f_version != inode->i_version) {
 812                         for (i = 0; i < i_size_read(inode) && i < offset; ) {
 813                                 de = (struct ocfs2_dir_entry *)
 814                                         (data->id_data + i);
 815                                 /* It's too expensive to do a full
 816                                  * dirent test each time round this
 817                                  * loop, but we do have to test at
 818                                  * least that it is non-zero.  A
 819                                  * failure will be detected in the
 820                                  * dirent test below. */
 821                                 if (le16_to_cpu(de->rec_len) <
 822                                     OCFS2_DIR_REC_LEN(1))
 823                                         break;
 824                                 i += le16_to_cpu(de->rec_len);
 825                         }
 826                         *f_pos = offset = i;
 827                         *f_version = inode->i_version;
 828                 }
 829
 830                 de = (struct ocfs2_dir_entry *) (data->id_data + *f_pos);
 831                 if (!ocfs2_check_dir_entry(inode, de, di_bh, *f_pos)) {
 832                         /* On error, skip the f_pos to the end. */
 833                         *f_pos = i_size_read(inode);
 834                         goto out;
 835                 }
 836                 offset += le16_to_cpu(de->rec_len);
 837                 if (le64_to_cpu(de->inode)) {
 838                         /* We might block in the next section
 839                          * if the data destination is
 840                          * currently swapped out.  So, use a
 841                          * version stamp to detect whether or
 842                          * not the directory has been modified
 843                          * during the copy operation.
 844                          */
 845                         u64 version = *f_version;
 846                         unsigned char d_type = DT_UNKNOWN;
 847
 848                         if (de->file_type < OCFS2_FT_MAX)
 849                                 d_type = ocfs2_filetype_table[de->file_type];
 850
 851                         filldir_ret = filldir(priv, de->name,
 852                                               de->name_len,
 853                                               *f_pos,
 854                                               le64_to_cpu(de->inode),
 855                                               d_type);
 856                         if (filldir_ret) {
 857                                 if (filldir_err)
 858                                         *filldir_err = filldir_ret;
 859                                 break;
 860                         }
 861                         if (version != *f_version)
 862                                 goto revalidate;
 863                 }
 864                 *f_pos += le16_to_cpu(de->rec_len);
 865         }
 866
 867 out:
 868         brelse(di_bh);
 869
 870         return 0;
 871 }
 872
 873 static int ocfs2_dir_foreach_blk_el(struct inode *inode,
 874                                     u64 *f_version,
 875                                     loff_t *f_pos, void *priv,
 876                                     filldir_t filldir, int *filldir_err)
 877 {
 878         int error = 0;
 879         unsigned long offset, blk, last_ra_blk = 0;
 880         int i, stored;
 881         struct buffer_head * bh, * tmp;
 882         struct ocfs2_dir_entry * de;
 883         struct super_block * sb = inode->i_sb;
 884         unsigned int ra_sectors = 16;
 885
 886         stored = 0;
 887         bh = NULL;
 888
 889         offset = (*f_pos) & (sb->s_blocksize - 1);
 890
 891         while (!error && !stored && *f_pos < i_size_read(inode)) {
 892                 blk = (*f_pos) >> sb->s_blocksize_bits;
 893                 if (ocfs2_read_dir_block(inode, blk, &bh, 0)) {
 894                         /* Skip the corrupt dirblock and keep trying */
 895                         *f_pos += sb->s_blocksize - offset;
 896                         continue;
 897                 }
 898
 899                 /* The idea here is to begin with 8k read-ahead and to stay
 900                  * 4k ahead of our current position.
 901                  *
 902                  * TODO: Use the pagecache for this. We just need to
 903                  * make sure it's cluster-safe... */
 904                 if (!last_ra_blk
 905                     || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
 906                         for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
 907                              i > 0; i--) {
 908                                 tmp = NULL;
 909                                 if (!ocfs2_read_dir_block(inode, ++blk, &tmp,
 910                                                           OCFS2_BH_READAHEAD))
 911                                         brelse(tmp);
 912                         }
 913                         last_ra_blk = blk;
 914                         ra_sectors = 8;
 915                 }
 916
 917 revalidate:
 918                 /* If the dir block has changed since the last call to
 919                  * readdir(2), then we might be pointing to an invalid
 920                  * dirent right now.  Scan from the start of the block
 921                  * to make sure. */
 922                 if (*f_version != inode->i_version) {
 923                         for (i = 0; i < sb->s_blocksize && i < offset; ) {
 924                                 de = (struct ocfs2_dir_entry *) (bh->b_data + i);
 925                                 /* It's too expensive to do a full
 926                                  * dirent test each time round this
 927                                  * loop, but we do have to test at
 928                                  * least that it is non-zero.  A
 929                                  * failure will be detected in the
 930                                  * dirent test below. */
 931                                 if (le16_to_cpu(de->rec_len) <
 932                                     OCFS2_DIR_REC_LEN(1))
 933                                         break;
 934                                 i += le16_to_cpu(de->rec_len);
 935                         }
 936                         offset = i;
 937                         *f_pos = ((*f_pos) & ~(sb->s_blocksize - 1))
 938                                 | offset;
 939                         *f_version = inode->i_version;
 940                 }
 941
 942                 while (!error && *f_pos < i_size_read(inode)
 943                        && offset < sb->s_blocksize) {
 944                         de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
 945                         if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
 946                                 /* On error, skip the f_pos to the
 947                                    next block. */
 948                                 *f_pos = ((*f_pos) | (sb->s_blocksize - 1)) + 1;
 949                                 brelse(bh);
 950                                 goto out;
 951                         }
 952                         offset += le16_to_cpu(de->rec_len);
 953                         if (le64_to_cpu(de->inode)) {
 954                                 /* We might block in the next section
 955                                  * if the data destination is
 956                                  * currently swapped out.  So, use a
 957                                  * version stamp to detect whether or
 958                                  * not the directory has been modified
 959                                  * during the copy operation.
 960                                  */
 961                                 unsigned long version = *f_version;
 962                                 unsigned char d_type = DT_UNKNOWN;
 963
 964                                 if (de->file_type < OCFS2_FT_MAX)
 965                                         d_type = ocfs2_filetype_table[de->file_type];
 966                                 error = filldir(priv, de->name,
 967                                                 de->name_len,
 968                                                 *f_pos,
 969                                                 le64_to_cpu(de->inode),
 970                                                 d_type);
 971                                 if (error) {
 972                                         if (filldir_err)
 973                                                 *filldir_err = error;
 974                                         break;
 975                                 }
 976                                 if (version != *f_version)
 977                                         goto revalidate;
 978                                 stored ++;
 979                         }
 980                         *f_pos += le16_to_cpu(de->rec_len);
 981                 }
 982                 offset = 0;
 983                 brelse(bh);
 984                 bh = NULL;
 985         }
 986
 987         stored = 0;
 988 out:
 989         return stored;
 990 }
 991
 992 static int ocfs2_dir_foreach_blk(struct inode *inode, u64 *f_version,
 993                                  loff_t *f_pos, void *priv, filldir_t filldir,
 994                                  int *filldir_err)
 995 {
 996         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 997                 return ocfs2_dir_foreach_blk_id(inode, f_version, f_pos, priv,
 998                                                 filldir, filldir_err);
 999
1000         return ocfs2_dir_foreach_blk_el(inode, f_version, f_pos, priv, filldir,
1001                                         filldir_err);
1002 }
1003
1004 /*
1005  * This is intended to be called from inside other kernel functions,
1006  * so we fake some arguments.
1007  */
1008 int ocfs2_dir_foreach(struct inode *inode, loff_t *f_pos, void *priv,
1009                       filldir_t filldir)
1010 {
1011         int ret = 0, filldir_err = 0;
1012         u64 version = inode->i_version;
1013
1014         while (*f_pos < i_size_read(inode)) {
1015                 ret = ocfs2_dir_foreach_blk(inode, &version, f_pos, priv,
1016                                             filldir, &filldir_err);
1017                 if (ret || filldir_err)
1018                         break;
1019         }
1020
1021         if (ret > 0)
1022                 ret = -EIO;
1023
1024         return 0;
1025 }
1026
1027 /*
1028  * ocfs2_readdir()
1029  *
1030  */
1031 int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
1032 {
1033         int error = 0;
1034         struct inode *inode = filp->f_path.dentry->d_inode;
1035         int lock_level = 0;
1036
1037         mlog_entry("dirino=%llu\n",
1038                    (unsigned long long)OCFS2_I(inode)->ip_blkno);
1039
1040         error = ocfs2_inode_lock_atime(inode, filp->f_vfsmnt, &lock_level);
1041         if (lock_level && error >= 0) {
1042                 /* We release EX lock which used to update atime
1043                  * and get PR lock again to reduce contention
1044                  * on commonly accessed directories. */
1045                 ocfs2_inode_unlock(inode, 1);
1046                 lock_level = 0;
1047                 error = ocfs2_inode_lock(inode, NULL, 0);
1048         }
1049         if (error < 0) {
1050                 if (error != -ENOENT)
1051                         mlog_errno(error);
1052                 /* we haven't got any yet, so propagate the error. */
1053                 goto bail_nolock;
1054         }
1055
1056         error = ocfs2_dir_foreach_blk(inode, &filp->f_version, &filp->f_pos,
1057                                       dirent, filldir, NULL);
1058
1059         ocfs2_inode_unlock(inode, lock_level);
1060
1061 bail_nolock:
1062         mlog_exit(error);
1063
1064         return error;
1065 }
1066
1067 /*
1068  * NOTE: this should always be called with parent dir i_mutex taken.
1069  */
1070 int ocfs2_find_files_on_disk(const char *name,
1071                              int namelen,
1072                              u64 *blkno,
1073                              struct inode *inode,
1074                              struct buffer_head **dirent_bh,
1075                              struct ocfs2_dir_entry **dirent)
1076 {
1077         int status = -ENOENT;
1078
1079         mlog_entry("(name=%.*s, blkno=%p, inode=%p, dirent_bh=%p, dirent=%p)\n",
1080                    namelen, name, blkno, inode, dirent_bh, dirent);
1081
1082         *dirent_bh = ocfs2_find_entry(name, namelen, inode, dirent);
1083         if (!*dirent_bh || !*dirent) {
1084                 status = -ENOENT;
1085                 goto leave;
1086         }
1087
1088         *blkno = le64_to_cpu((*dirent)->inode);
1089
1090         status = 0;
1091 leave:
1092         if (status < 0) {
1093                 *dirent = NULL;
1094                 brelse(*dirent_bh);
1095                 *dirent_bh = NULL;
1096         }
1097
1098         mlog_exit(status);
1099         return status;
1100 }
1101
1102 /*
1103  * Convenience function for callers which just want the block number
1104  * mapped to a name and don't require the full dirent info, etc.
1105  */
1106 int ocfs2_lookup_ino_from_name(struct inode *dir, const char *name,
1107                                int namelen, u64 *blkno)
1108 {
1109         int ret;
1110         struct buffer_head *bh = NULL;
1111         struct ocfs2_dir_entry *dirent = NULL;
1112
1113         ret = ocfs2_find_files_on_disk(name, namelen, blkno, dir, &bh, &dirent);
1114         brelse(bh);
1115
1116         return ret;
1117 }
1118
1119 /* Check for a name within a directory.
1120  *
1121  * Return 0 if the name does not exist
1122  * Return -EEXIST if the directory contains the name
1123  *
1124  * Callers should have i_mutex + a cluster lock on dir
1125  */
1126 int ocfs2_check_dir_for_entry(struct inode *dir,
1127                               const char *name,
1128                               int namelen)
1129 {
1130         int ret;
1131         struct buffer_head *dirent_bh = NULL;
1132         struct ocfs2_dir_entry *dirent = NULL;
1133
1134         mlog_entry("dir %llu, name '%.*s'\n",
1135                    (unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
1136
1137         ret = -EEXIST;
1138         dirent_bh = ocfs2_find_entry(name, namelen, dir, &dirent);
1139         if (dirent_bh)
1140                 goto bail;
1141
1142         ret = 0;
1143 bail:
1144         brelse(dirent_bh);
1145
1146         mlog_exit(ret);
1147         return ret;
1148 }
1149
1150 struct ocfs2_empty_dir_priv {
1151         unsigned seen_dot;
1152         unsigned seen_dot_dot;
1153         unsigned seen_other;
1154 };
1155 static int ocfs2_empty_dir_filldir(void *priv, const char *name, int name_len,
1156                                    loff_t pos, u64 ino, unsigned type)
1157 {
1158         struct ocfs2_empty_dir_priv *p = priv;
1159
1160         /*
1161          * Check the positions of "." and ".." records to be sure
1162          * they're in the correct place.
1163          */
1164         if (name_len == 1 && !strncmp(".", name, 1) && pos == 0) {
1165                 p->seen_dot = 1;
1166                 return 0;
1167         }
1168
1169         if (name_len == 2 && !strncmp("..", name, 2) &&
1170             pos == OCFS2_DIR_REC_LEN(1)) {
1171                 p->seen_dot_dot = 1;
1172                 return 0;
1173         }
1174
1175         p->seen_other = 1;
1176         return 1;
1177 }
1178 /*
1179  * routine to check that the specified directory is empty (for rmdir)
1180  *
1181  * Returns 1 if dir is empty, zero otherwise.
1182  */
1183 int ocfs2_empty_dir(struct inode *inode)
1184 {
1185         int ret;
1186         loff_t start = 0;
1187         struct ocfs2_empty_dir_priv priv;
1188
1189         memset(&priv, 0, sizeof(priv));
1190
1191         ret = ocfs2_dir_foreach(inode, &start, &priv, ocfs2_empty_dir_filldir);
1192         if (ret)
1193                 mlog_errno(ret);
1194
1195         if (!priv.seen_dot || !priv.seen_dot_dot) {
1196                 mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
1197                      (unsigned long long)OCFS2_I(inode)->ip_blkno);
1198                 /*
1199                  * XXX: Is it really safe to allow an unlink to continue?
1200                  */
1201                 return 1;
1202         }
1203
1204         return !priv.seen_other;
1205 }
1206
1207 /*
1208  * Fills "." and ".." dirents in a new directory block. Returns dirent for
1209  * "..", which might be used during creation of a directory with a trailing
1210  * header. It is otherwise safe to ignore the return code.
1211  */
1212 static struct ocfs2_dir_entry *ocfs2_fill_initial_dirents(struct inode *inode,
1213                                                           struct inode *parent,
1214                                                           char *start,
1215                                                           unsigned int size)
1216 {
1217         struct ocfs2_dir_entry *de = (struct ocfs2_dir_entry *)start;
1218
1219         de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
1220         de->name_len = 1;
1221         de->rec_len =
1222                 cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
1223         strcpy(de->name, ".");
1224         ocfs2_set_de_type(de, S_IFDIR);
1225
1226         de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
1227         de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
1228         de->rec_len = cpu_to_le16(size - OCFS2_DIR_REC_LEN(1));
1229         de->name_len = 2;
1230         strcpy(de->name, "..");
1231         ocfs2_set_de_type(de, S_IFDIR);
1232
1233         return de;
1234 }
1235
1236 /*
1237  * This works together with code in ocfs2_mknod_locked() which sets
1238  * the inline-data flag and initializes the inline-data section.
1239  */
1240 static int ocfs2_fill_new_dir_id(struct ocfs2_super *osb,
1241                                  handle_t *handle,
1242                                  struct inode *parent,
1243                                  struct inode *inode,
1244                                  struct buffer_head *di_bh)
1245 {
1246         int ret;
1247         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1248         struct ocfs2_inline_data *data = &di->id2.i_data;
1249         unsigned int size = le16_to_cpu(data->id_count);
1250
1251         ret = ocfs2_journal_access_di(handle, inode, di_bh,
1252                                       OCFS2_JOURNAL_ACCESS_WRITE);
1253         if (ret) {
1254                 mlog_errno(ret);
1255                 goto out;
1256         }
1257
1258         ocfs2_fill_initial_dirents(inode, parent, data->id_data, size);
1259
1260         ocfs2_journal_dirty(handle, di_bh);
1261         if (ret) {
1262                 mlog_errno(ret);
1263                 goto out;
1264         }
1265
1266         i_size_write(inode, size);
1267         inode->i_nlink = 2;
1268         inode->i_blocks = ocfs2_inode_sector_count(inode);
1269
1270         ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
1271         if (ret < 0)
1272                 mlog_errno(ret);
1273
1274 out:
1275         return ret;
1276 }
1277
1278 static int ocfs2_fill_new_dir_el(struct ocfs2_super *osb,
1279                                  handle_t *handle,
1280                                  struct inode *parent,
1281                                  struct inode *inode,
1282                                  struct buffer_head *fe_bh,
1283                                  struct ocfs2_alloc_context *data_ac)
1284 {
1285         int status;
1286         unsigned int size = osb->sb->s_blocksize;
1287         struct buffer_head *new_bh = NULL;
1288         struct ocfs2_dir_entry *de;
1289
1290         mlog_entry_void();
1291
1292         if (ocfs2_supports_dir_trailer(osb))
1293                 size = ocfs2_dir_trailer_blk_off(parent->i_sb);
1294
1295         status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
1296                                      data_ac, NULL, &new_bh);
1297         if (status < 0) {
1298                 mlog_errno(status);
1299                 goto bail;
1300         }
1301
1302         ocfs2_set_new_buffer_uptodate(inode, new_bh);
1303
1304         status = ocfs2_journal_access_db(handle, inode, new_bh,
1305                                          OCFS2_JOURNAL_ACCESS_CREATE);
1306         if (status < 0) {
1307                 mlog_errno(status);
1308                 goto bail;
1309         }
1310         memset(new_bh->b_data, 0, osb->sb->s_blocksize);
1311
1312         de = ocfs2_fill_initial_dirents(inode, parent, new_bh->b_data, size);
1313         if (ocfs2_supports_dir_trailer(osb))
1314                 ocfs2_init_dir_trailer(inode, new_bh);
1315
1316         status = ocfs2_journal_dirty(handle, new_bh);
1317         if (status < 0) {
1318                 mlog_errno(status);
1319                 goto bail;
1320         }
1321
1322         i_size_write(inode, inode->i_sb->s_blocksize);
1323         inode->i_nlink = 2;
1324         inode->i_blocks = ocfs2_inode_sector_count(inode);
1325         status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
1326         if (status < 0) {
1327                 mlog_errno(status);
1328                 goto bail;
1329         }
1330
1331         status = 0;
1332 bail:
1333         brelse(new_bh);
1334
1335         mlog_exit(status);
1336         return status;
1337 }
1338
1339 int ocfs2_fill_new_dir(struct ocfs2_super *osb,
1340                        handle_t *handle,
1341                        struct inode *parent,
1342                        struct inode *inode,
1343                        struct buffer_head *fe_bh,
1344                        struct ocfs2_alloc_context *data_ac)
1345 {
1346         BUG_ON(!ocfs2_supports_inline_data(osb) && data_ac == NULL);
1347
1348         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1349                 return ocfs2_fill_new_dir_id(osb, handle, parent, inode, fe_bh);
1350
1351         return ocfs2_fill_new_dir_el(osb, handle, parent, inode, fe_bh,
1352                                      data_ac);
1353 }
1354
1355 /*
1356  * Expand rec_len of the rightmost dirent in a directory block so that it
1357  * contains the end of our valid space for dirents. We do this during
1358  * expansion from an inline directory to one with extents. The first dir block
1359  * in that case is taken from the inline data portion of the inode block.
1360  *
1361  * We add the dir trailer if this filesystem wants it.
1362  */
1363 static void ocfs2_expand_last_dirent(char *start, unsigned int old_size,
1364                                      struct super_block *sb)
1365 {
1366         struct ocfs2_dir_entry *de;
1367         struct ocfs2_dir_entry *prev_de;
1368         char *de_buf, *limit;
1369         unsigned int new_size = sb->s_blocksize;
1370         unsigned int bytes;
1371
1372         if (ocfs2_supports_dir_trailer(OCFS2_SB(sb)))
1373                 new_size = ocfs2_dir_trailer_blk_off(sb);
1374
1375         bytes = new_size - old_size;
1376
1377         limit = start + old_size;
1378         de_buf = start;
1379         de = (struct ocfs2_dir_entry *)de_buf;
1380         do {
1381                 prev_de = de;
1382                 de_buf += le16_to_cpu(de->rec_len);
1383                 de = (struct ocfs2_dir_entry *)de_buf;
1384         } while (de_buf < limit);
1385
1386         le16_add_cpu(&prev_de->rec_len, bytes);
1387 }
1388
1389 /*
1390  * We allocate enough clusters to fulfill "blocks_wanted", but set
1391  * i_size to exactly one block. Ocfs2_extend_dir() will handle the
1392  * rest automatically for us.
1393  *
1394  * *first_block_bh is a pointer to the 1st data block allocated to the
1395  *  directory.
1396  */
1397 static int ocfs2_expand_inline_dir(struct inode *dir, struct buffer_head *di_bh,
1398                                    unsigned int blocks_wanted,
1399                                    struct buffer_head **first_block_bh)
1400 {
1401         u32 alloc, bit_off, len;
1402         struct super_block *sb = dir->i_sb;
1403         int ret, credits = ocfs2_inline_to_extents_credits(sb);
1404         u64 blkno, bytes = blocks_wanted << sb->s_blocksize_bits;
1405         struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
1406         struct ocfs2_inode_info *oi = OCFS2_I(dir);
1407         struct ocfs2_alloc_context *data_ac;
1408         struct buffer_head *dirdata_bh = NULL;
1409         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1410         handle_t *handle;
1411         struct ocfs2_extent_tree et;
1412         int did_quota = 0;
1413
1414         ocfs2_init_dinode_extent_tree(&et, dir, di_bh);
1415
1416         alloc = ocfs2_clusters_for_bytes(sb, bytes);
1417
1418         /*
1419          * We should never need more than 2 clusters for this -
1420          * maximum dirent size is far less than one block. In fact,
1421          * the only time we'd need more than one cluster is if
1422          * blocksize == clustersize and the dirent won't fit in the
1423          * extra space that the expansion to a single block gives. As
1424          * of today, that only happens on 4k/4k file systems.
1425          */
1426         BUG_ON(alloc > 2);
1427
1428         ret = ocfs2_reserve_clusters(osb, alloc, &data_ac);
1429         if (ret) {
1430                 mlog_errno(ret);
1431                 goto out;
1432         }
1433
1434         down_write(&oi->ip_alloc_sem);
1435
1436         /*
1437          * Prepare for worst case allocation scenario of two separate
1438          * extents.
1439          */
1440         if (alloc == 2)
1441                 credits += OCFS2_SUBALLOC_ALLOC;
1442
1443         handle = ocfs2_start_trans(osb, credits);
1444         if (IS_ERR(handle)) {
1445                 ret = PTR_ERR(handle);
1446                 mlog_errno(ret);
1447                 goto out_sem;
1448         }
1449
1450         if (vfs_dq_alloc_space_nodirty(dir,
1451                                 ocfs2_clusters_to_bytes(osb->sb, alloc))) {
1452                 ret = -EDQUOT;
1453                 goto out_commit;
1454         }
1455         did_quota = 1;
1456         /*
1457          * Try to claim as many clusters as the bitmap can give though
1458          * if we only get one now, that's enough to continue. The rest
1459          * will be claimed after the conversion to extents.
1460          */
1461         ret = ocfs2_claim_clusters(osb, handle, data_ac, 1, &bit_off, &len);
1462         if (ret) {
1463                 mlog_errno(ret);
1464                 goto out_commit;
1465         }
1466
1467         /*
1468          * Operations are carefully ordered so that we set up the new
1469          * data block first. The conversion from inline data to
1470          * extents follows.
1471          */
1472         blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
1473         dirdata_bh = sb_getblk(sb, blkno);
1474         if (!dirdata_bh) {
1475                 ret = -EIO;
1476                 mlog_errno(ret);
1477                 goto out_commit;
1478         }
1479
1480         ocfs2_set_new_buffer_uptodate(dir, dirdata_bh);
1481
1482         ret = ocfs2_journal_access_db(handle, dir, dirdata_bh,
1483                                       OCFS2_JOURNAL_ACCESS_CREATE);
1484         if (ret) {
1485                 mlog_errno(ret);
1486                 goto out_commit;
1487         }
1488
1489         memcpy(dirdata_bh->b_data, di->id2.i_data.id_data, i_size_read(dir));
1490         memset(dirdata_bh->b_data + i_size_read(dir), 0,
1491                sb->s_blocksize - i_size_read(dir));
1492         ocfs2_expand_last_dirent(dirdata_bh->b_data, i_size_read(dir), sb);
1493         if (ocfs2_supports_dir_trailer(osb))
1494                 ocfs2_init_dir_trailer(dir, dirdata_bh);
1495
1496         ret = ocfs2_journal_dirty(handle, dirdata_bh);
1497         if (ret) {
1498                 mlog_errno(ret);
1499                 goto out_commit;
1500         }
1501
1502         /*
1503          * Set extent, i_size, etc on the directory. After this, the
1504          * inode should contain the same exact dirents as before and
1505          * be fully accessible from system calls.
1506          *
1507          * We let the later dirent insert modify c/mtime - to the user
1508          * the data hasn't changed.
1509          */
1510         ret = ocfs2_journal_access_di(handle, dir, di_bh,
1511                                       OCFS2_JOURNAL_ACCESS_CREATE);
1512         if (ret) {
1513                 mlog_errno(ret);
1514                 goto out_commit;
1515         }
1516
1517         spin_lock(&oi->ip_lock);
1518         oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
1519         di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
1520         spin_unlock(&oi->ip_lock);
1521
1522         ocfs2_dinode_new_extent_list(dir, di);
1523
1524         i_size_write(dir, sb->s_blocksize);
1525         dir->i_mtime = dir->i_ctime = CURRENT_TIME;
1526
1527         di->i_size = cpu_to_le64(sb->s_blocksize);
1528         di->i_ctime = di->i_mtime = cpu_to_le64(dir->i_ctime.tv_sec);
1529         di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(dir->i_ctime.tv_nsec);
1530
1531         /*
1532          * This should never fail as our extent list is empty and all
1533          * related blocks have been journaled already.
1534          */
1535         ret = ocfs2_insert_extent(osb, handle, dir, &et, 0, blkno, len,
1536                                   0, NULL);
1537         if (ret) {
1538                 mlog_errno(ret);
1539                 goto out_commit;
1540         }
1541
1542         /*
1543          * Set i_blocks after the extent insert for the most up to
1544          * date ip_clusters value.
1545          */
1546         dir->i_blocks = ocfs2_inode_sector_count(dir);
1547
1548         ret = ocfs2_journal_dirty(handle, di_bh);
1549         if (ret) {
1550                 mlog_errno(ret);
1551                 goto out_commit;
1552         }
1553
1554         /*
1555          * We asked for two clusters, but only got one in the 1st
1556          * pass. Claim the 2nd cluster as a separate extent.
1557          */
1558         if (alloc > len) {
1559                 ret = ocfs2_claim_clusters(osb, handle, data_ac, 1, &bit_off,
1560                                            &len);
1561                 if (ret) {
1562                         mlog_errno(ret);
1563                         goto out_commit;
1564                 }
1565                 blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
1566
1567                 ret = ocfs2_insert_extent(osb, handle, dir, &et, 1,
1568                                           blkno, len, 0, NULL);
1569                 if (ret) {
1570                         mlog_errno(ret);
1571                         goto out_commit;
1572                 }
1573         }
1574
1575         *first_block_bh = dirdata_bh;
1576         dirdata_bh = NULL;
1577
1578 out_commit:
1579         if (ret < 0 && did_quota)
1580                 vfs_dq_free_space_nodirty(dir,
1581                         ocfs2_clusters_to_bytes(osb->sb, 2));
1582         ocfs2_commit_trans(osb, handle);
1583
1584 out_sem:
1585         up_write(&oi->ip_alloc_sem);
1586
1587 out:
1588         if (data_ac)
1589                 ocfs2_free_alloc_context(data_ac);
1590
1591         brelse(dirdata_bh);
1592
1593         return ret;
1594 }
1595
1596 /* returns a bh of the 1st new block in the allocation. */
1597 static int ocfs2_do_extend_dir(struct super_block *sb,
1598                                handle_t *handle,
1599                                struct inode *dir,
1600                                struct buffer_head *parent_fe_bh,
1601                                struct ocfs2_alloc_context *data_ac,
1602                                struct ocfs2_alloc_context *meta_ac,
1603                                struct buffer_head **new_bh)
1604 {
1605         int status;
1606         int extend, did_quota = 0;
1607         u64 p_blkno, v_blkno;
1608
1609         spin_lock(&OCFS2_I(dir)->ip_lock);
1610         extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
1611         spin_unlock(&OCFS2_I(dir)->ip_lock);
1612
1613         if (extend) {
1614                 u32 offset = OCFS2_I(dir)->ip_clusters;
1615
1616                 if (vfs_dq_alloc_space_nodirty(dir,
1617                                         ocfs2_clusters_to_bytes(sb, 1))) {
1618                         status = -EDQUOT;
1619                         goto bail;
1620                 }
1621                 did_quota = 1;
1622
1623                 status = ocfs2_add_inode_data(OCFS2_SB(sb), dir, &offset,
1624                                               1, 0, parent_fe_bh, handle,
1625                                               data_ac, meta_ac, NULL);
1626                 BUG_ON(status == -EAGAIN);
1627                 if (status < 0) {
1628                         mlog_errno(status);
1629                         goto bail;
1630                 }
1631         }
1632
1633         v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
1634         status = ocfs2_extent_map_get_blocks(dir, v_blkno, &p_blkno, NULL, NULL);
1635         if (status < 0) {
1636                 mlog_errno(status);
1637                 goto bail;
1638         }
1639
1640         *new_bh = sb_getblk(sb, p_blkno);
1641         if (!*new_bh) {
1642                 status = -EIO;
1643                 mlog_errno(status);
1644                 goto bail;
1645         }
1646         status = 0;
1647 bail:
1648         if (did_quota && status < 0)
1649                 vfs_dq_free_space_nodirty(dir, ocfs2_clusters_to_bytes(sb, 1));
1650         mlog_exit(status);
1651         return status;
1652 }
1653
1654 /*
1655  * Assumes you already have a cluster lock on the directory.
1656  *
1657  * 'blocks_wanted' is only used if we have an inline directory which
1658  * is to be turned into an extent based one. The size of the dirent to
1659  * insert might be larger than the space gained by growing to just one
1660  * block, so we may have to grow the inode by two blocks in that case.
1661  */
1662 static int ocfs2_extend_dir(struct ocfs2_super *osb,
1663                             struct inode *dir,
1664                             struct buffer_head *parent_fe_bh,
1665                             unsigned int blocks_wanted,
1666                             struct buffer_head **new_de_bh)
1667 {
1668         int status = 0;
1669         int credits, num_free_extents, drop_alloc_sem = 0;
1670         loff_t dir_i_size;
1671         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
1672         struct ocfs2_extent_list *el = &fe->id2.i_list;
1673         struct ocfs2_alloc_context *data_ac = NULL;
1674         struct ocfs2_alloc_context *meta_ac = NULL;
1675         handle_t *handle = NULL;
1676         struct buffer_head *new_bh = NULL;
1677         struct ocfs2_dir_entry * de;
1678         struct super_block *sb = osb->sb;
1679         struct ocfs2_extent_tree et;
1680
1681         mlog_entry_void();
1682
1683         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1684                 status = ocfs2_expand_inline_dir(dir, parent_fe_bh,
1685                                                  blocks_wanted, &new_bh);
1686                 if (status) {
1687                         mlog_errno(status);
1688                         goto bail;
1689                 }
1690
1691                 if (blocks_wanted == 1) {
1692                         /*
1693                          * If the new dirent will fit inside the space
1694                          * created by pushing out to one block, then
1695                          * we can complete the operation
1696                          * here. Otherwise we have to expand i_size
1697                          * and format the 2nd block below.
1698                          */
1699                         BUG_ON(new_bh == NULL);
1700                         goto bail_bh;
1701                 }
1702
1703                 /*
1704                  * Get rid of 'new_bh' - we want to format the 2nd
1705                  * data block and return that instead.
1706                  */
1707                 brelse(new_bh);
1708                 new_bh = NULL;
1709
1710                 dir_i_size = i_size_read(dir);
1711                 credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
1712                 goto do_extend;
1713         }
1714
1715         dir_i_size = i_size_read(dir);
1716         mlog(0, "extending dir %llu (i_size = %lld)\n",
1717              (unsigned long long)OCFS2_I(dir)->ip_blkno, dir_i_size);
1718
1719         /* dir->i_size is always block aligned. */
1720         spin_lock(&OCFS2_I(dir)->ip_lock);
1721         if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
1722                 spin_unlock(&OCFS2_I(dir)->ip_lock);
1723                 ocfs2_init_dinode_extent_tree(&et, dir, parent_fe_bh);
1724                 num_free_extents = ocfs2_num_free_extents(osb, dir, &et);
1725                 if (num_free_extents < 0) {
1726                         status = num_free_extents;
1727                         mlog_errno(status);
1728                         goto bail;
1729                 }
1730
1731                 if (!num_free_extents) {
1732                         status = ocfs2_reserve_new_metadata(osb, el, &meta_ac);
1733                         if (status < 0) {
1734                                 if (status != -ENOSPC)
1735                                         mlog_errno(status);
1736                                 goto bail;
1737                         }
1738                 }
1739
1740                 status = ocfs2_reserve_clusters(osb, 1, &data_ac);
1741                 if (status < 0) {
1742                         if (status != -ENOSPC)
1743                                 mlog_errno(status);
1744                         goto bail;
1745                 }
1746
1747                 credits = ocfs2_calc_extend_credits(sb, el, 1);
1748         } else {
1749                 spin_unlock(&OCFS2_I(dir)->ip_lock);
1750                 credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
1751         }
1752
1753 do_extend:
1754         down_write(&OCFS2_I(dir)->ip_alloc_sem);
1755         drop_alloc_sem = 1;
1756
1757         handle = ocfs2_start_trans(osb, credits);
1758         if (IS_ERR(handle)) {
1759                 status = PTR_ERR(handle);
1760                 handle = NULL;
1761                 mlog_errno(status);
1762                 goto bail;
1763         }
1764
1765         status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
1766                                      data_ac, meta_ac, &new_bh);
1767         if (status < 0) {
1768                 mlog_errno(status);
1769                 goto bail;
1770         }
1771
1772         ocfs2_set_new_buffer_uptodate(dir, new_bh);
1773
1774         status = ocfs2_journal_access_db(handle, dir, new_bh,
1775                                          OCFS2_JOURNAL_ACCESS_CREATE);
1776         if (status < 0) {
1777                 mlog_errno(status);
1778                 goto bail;
1779         }
1780         memset(new_bh->b_data, 0, sb->s_blocksize);
1781
1782         de = (struct ocfs2_dir_entry *) new_bh->b_data;
1783         de->inode = 0;
1784         if (ocfs2_dir_has_trailer(dir)) {
1785                 de->rec_len = cpu_to_le16(ocfs2_dir_trailer_blk_off(sb));
1786                 ocfs2_init_dir_trailer(dir, new_bh);
1787         } else {
1788                 de->rec_len = cpu_to_le16(sb->s_blocksize);
1789         }
1790         status = ocfs2_journal_dirty(handle, new_bh);
1791         if (status < 0) {
1792                 mlog_errno(status);
1793                 goto bail;
1794         }
1795
1796         dir_i_size += dir->i_sb->s_blocksize;
1797         i_size_write(dir, dir_i_size);
1798         dir->i_blocks = ocfs2_inode_sector_count(dir);
1799         status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
1800         if (status < 0) {
1801                 mlog_errno(status);
1802                 goto bail;
1803         }
1804
1805 bail_bh:
1806         *new_de_bh = new_bh;
1807         get_bh(*new_de_bh);
1808 bail:
1809         if (drop_alloc_sem)
1810                 up_write(&OCFS2_I(dir)->ip_alloc_sem);
1811         if (handle)
1812                 ocfs2_commit_trans(osb, handle);
1813
1814         if (data_ac)
1815                 ocfs2_free_alloc_context(data_ac);
1816         if (meta_ac)
1817                 ocfs2_free_alloc_context(meta_ac);
1818
1819         brelse(new_bh);
1820
1821         mlog_exit(status);
1822         return status;
1823 }
1824
1825 static int ocfs2_find_dir_space_id(struct inode *dir, struct buffer_head *di_bh,
1826                                    const char *name, int namelen,
1827                                    struct buffer_head **ret_de_bh,
1828                                    unsigned int *blocks_wanted)
1829 {
1830         int ret;
1831         struct super_block *sb = dir->i_sb;
1832         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1833         struct ocfs2_dir_entry *de, *last_de = NULL;
1834         char *de_buf, *limit;
1835         unsigned long offset = 0;
1836         unsigned int rec_len, new_rec_len, free_space = dir->i_sb->s_blocksize;
1837
1838         /*
1839          * This calculates how many free bytes we'd have in block zero, should
1840          * this function force expansion to an extent tree.
1841          */
1842         if (ocfs2_supports_dir_trailer(OCFS2_SB(sb)))
1843                 free_space = ocfs2_dir_trailer_blk_off(sb) - i_size_read(dir);
1844         else
1845                 free_space = dir->i_sb->s_blocksize - i_size_read(dir);
1846
1847         de_buf = di->id2.i_data.id_data;
1848         limit = de_buf + i_size_read(dir);
1849         rec_len = OCFS2_DIR_REC_LEN(namelen);
1850
1851         while (de_buf < limit) {
1852                 de = (struct ocfs2_dir_entry *)de_buf;
1853
1854                 if (!ocfs2_check_dir_entry(dir, de, di_bh, offset)) {
1855                         ret = -ENOENT;
1856                         goto out;
1857                 }
1858                 if (ocfs2_match(namelen, name, de)) {
1859                         ret = -EEXIST;
1860                         goto out;
1861                 }
1862                 /*
1863                  * No need to check for a trailing dirent record here as
1864                  * they're not used for inline dirs.
1865                  */
1866
1867                 if (ocfs2_dirent_would_fit(de, rec_len)) {
1868                         /* Ok, we found a spot. Return this bh and let
1869                          * the caller actually fill it in. */
1870                         *ret_de_bh = di_bh;
1871                         get_bh(*ret_de_bh);
1872                         ret = 0;
1873                         goto out;
1874                 }
1875
1876                 last_de = de;
1877                 de_buf += le16_to_cpu(de->rec_len);
1878                 offset += le16_to_cpu(de->rec_len);
1879         }
1880
1881         /*
1882          * We're going to require expansion of the directory - figure
1883          * out how many blocks we'll need so that a place for the
1884          * dirent can be found.
1885          */
1886         *blocks_wanted = 1;
1887         new_rec_len = le16_to_cpu(last_de->rec_len) + free_space;
1888         if (new_rec_len < (rec_len + OCFS2_DIR_REC_LEN(last_de->name_len)))
1889                 *blocks_wanted = 2;
1890
1891         ret = -ENOSPC;
1892 out:
1893         return ret;
1894 }
1895
1896 static int ocfs2_find_dir_space_el(struct inode *dir, const char *name,
1897                                    int namelen, struct buffer_head **ret_de_bh)
1898 {
1899         unsigned long offset;
1900         struct buffer_head *bh = NULL;
1901         unsigned short rec_len;
1902         struct ocfs2_dir_entry *de;
1903         struct super_block *sb = dir->i_sb;
1904         int status;
1905         int blocksize = dir->i_sb->s_blocksize;
1906
1907         status = ocfs2_read_dir_block(dir, 0, &bh, 0);
1908         if (status) {
1909                 mlog_errno(status);
1910                 goto bail;
1911         }
1912
1913         rec_len = OCFS2_DIR_REC_LEN(namelen);
1914         offset = 0;
1915         de = (struct ocfs2_dir_entry *) bh->b_data;
1916         while (1) {
1917                 if ((char *)de >= sb->s_blocksize + bh->b_data) {
1918                         brelse(bh);
1919                         bh = NULL;
1920
1921                         if (i_size_read(dir) <= offset) {
1922                                 /*
1923                                  * Caller will have to expand this
1924                                  * directory.
1925                                  */
1926                                 status = -ENOSPC;
1927                                 goto bail;
1928                         }
1929                         status = ocfs2_read_dir_block(dir,
1930                                              offset >> sb->s_blocksize_bits,
1931                                              &bh, 0);
1932                         if (status) {
1933                                 mlog_errno(status);
1934                                 goto bail;
1935                         }
1936                         /* move to next block */
1937                         de = (struct ocfs2_dir_entry *) bh->b_data;
1938                 }
1939                 if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
1940                         status = -ENOENT;
1941                         goto bail;
1942                 }
1943                 if (ocfs2_match(namelen, name, de)) {
1944                         status = -EEXIST;
1945                         goto bail;
1946                 }
1947
1948                 if (ocfs2_skip_dir_trailer(dir, de, offset % blocksize,
1949                                            blocksize))
1950                         goto next;
1951
1952                 if (ocfs2_dirent_would_fit(de, rec_len)) {
1953                         /* Ok, we found a spot. Return this bh and let
1954                          * the caller actually fill it in. */
1955                         *ret_de_bh = bh;
1956                         get_bh(*ret_de_bh);
1957                         status = 0;
1958                         goto bail;
1959                 }
1960 next:
1961                 offset += le16_to_cpu(de->rec_len);
1962                 de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
1963         }
1964
1965         status = 0;
1966 bail:
1967         brelse(bh);
1968
1969         mlog_exit(status);
1970         return status;
1971 }
1972
1973 int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
1974                                  struct inode *dir,
1975                                  struct buffer_head *parent_fe_bh,
1976                                  const char *name,
1977                                  int namelen,
1978                                  struct buffer_head **ret_de_bh)
1979 {
1980         int ret;
1981         unsigned int blocks_wanted = 1;
1982         struct buffer_head *bh = NULL;
1983
1984         mlog(0, "getting ready to insert namelen %d into dir %llu\n",
1985              namelen, (unsigned long long)OCFS2_I(dir)->ip_blkno);
1986
1987         *ret_de_bh = NULL;
1988
1989         if (!namelen) {
1990                 ret = -EINVAL;
1991                 mlog_errno(ret);
1992                 goto out;
1993         }
1994
1995         if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1996                 ret = ocfs2_find_dir_space_id(dir, parent_fe_bh, name,
1997                                               namelen, &bh, &blocks_wanted);
1998         } else
1999                 ret = ocfs2_find_dir_space_el(dir, name, namelen, &bh);
2000
2001         if (ret && ret != -ENOSPC) {
2002                 mlog_errno(ret);
2003                 goto out;
2004         }
2005
2006         if (ret == -ENOSPC) {
2007                 /*
2008                  * We have to expand the directory to add this name.
2009                  */
2010                 BUG_ON(bh);
2011
2012                 ret = ocfs2_extend_dir(osb, dir, parent_fe_bh, blocks_wanted,
2013                                        &bh);
2014                 if (ret) {
2015                         if (ret != -ENOSPC)
2016                                 mlog_errno(ret);
2017                         goto out;
2018                 }
2019
2020                 BUG_ON(!bh);
2021         }
2022
2023         *ret_de_bh = bh;
2024         bh = NULL;
2025 out:
2026         brelse(bh);
2027         return ret;
2028 }