lustre/lvfs/fsfilt_ext3.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  lustre/lib/fsfilt_ext3.c
   5  *  Lustre filesystem abstraction routines
   6  *
   7  *  Copyright (C) 2002, 2003 Cluster File Systems, Inc.
   8  *   Author: Andreas Dilger <adilger@clusterfs.com>
   9  *
  10  *   This file is part of Lustre, http://www.lustre.org.
  11  *
  12  *   Lustre is free software; you can redistribute it and/or
  13  *   modify it under the terms of version 2 of the GNU General Public
  14  *   License as published by the Free Software Foundation.
  15  *
  16  *   Lustre is distributed in the hope that it will be useful,
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *   GNU General Public License for more details.
  20  *
  21  *   You should have received a copy of the GNU General Public License
  22  *   along with Lustre; if not, write to the Free Software
  23  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24  */
  25
  26 #define DEBUG_SUBSYSTEM S_FILTER
  27
  28 #include <linux/init.h>
  29 #include <linux/module.h>
  30 #include <linux/fs.h>
  31 #include <linux/jbd.h>
  32 #include <linux/slab.h>
  33 #include <linux/pagemap.h>
  34 #include <linux/quotaops.h>
  35 #include <linux/ext3_fs.h>
  36 #include <linux/ext3_jbd.h>
  37 #include <linux/ext3_extents.h>
  38 #include <linux/version.h>
  39 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  40 #include <linux/ext3_xattr.h>
  41 #else
  42 #include <ext3/xattr.h>
  43 #endif
  44
  45 #include <libcfs/kp30.h>
  46 #include <linux/lustre_fsfilt.h>
  47 #include <linux/obd.h>
  48 #include <linux/obd_class.h>
  49 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
  50 #include <linux/module.h>
  51 #include <linux/iobuf.h>
  52 #endif
  53
  54
  55 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,7))
  56 # define lock_24kernel() lock_kernel()
  57 # define unlock_24kernel() unlock_kernel()
  58 #else
  59 # define lock_24kernel() do {} while (0)
  60 # define unlock_24kernel() do {} while (0)
  61 #endif
  62
  63 static kmem_cache_t *fcb_cache;
  64 static atomic_t fcb_cache_count = ATOMIC_INIT(0);
  65
  66 struct fsfilt_cb_data {
  67         struct journal_callback cb_jcb; /* jbd private data - MUST BE FIRST */
  68         fsfilt_cb_t cb_func;            /* MDS/OBD completion function */
  69         struct obd_device *cb_obd;      /* MDS/OBD completion device */
  70         __u64 cb_last_num;              /* MDS/OST last committed operation */
  71         void *cb_data;                  /* MDS/OST completion function data */
  72 };
  73
  74 #ifndef EXT3_XATTR_INDEX_TRUSTED        /* temporary until we hit l28 kernel */
  75 #define EXT3_XATTR_INDEX_TRUSTED        4
  76 #endif
  77
  78 #define XATTR_LUSTRE_MDS_LOV_EA         "lov"
  79 #define XATTR_LUSTRE_MDS_MEA_EA         "mea"
  80 #define XATTR_LUSTRE_MDS_MID_EA         "mid"
  81 #define XATTR_LUSTRE_MDS_SID_EA         "sid"
  82
  83 /*
  84  * We don't currently need any additional blocks for rmdir and
  85  * unlink transactions because we are storing the OST oa_id inside
  86  * the inode (which we will be changing anyways as part of this
  87  * transaction).
  88  */
  89 static void *fsfilt_ext3_start(struct inode *inode, int op, void *desc_private,
  90                                int logs)
  91 {
  92         /* For updates to the last recieved file */
  93         int nblocks = EXT3_SINGLEDATA_TRANS_BLOCKS;
  94         journal_t *journal;
  95         void *handle;
  96
  97         if (current->journal_info) {
  98                 CDEBUG(D_INODE, "increasing refcount on %p\n",
  99                        current->journal_info);
 100                 goto journal_start;
 101         }
 102
 103         if (logs)
 104                 nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 105                             EXT3_SINGLEDATA_TRANS_BLOCKS) * logs;
 106
 107         switch(op) {
 108         case FSFILT_OP_RMDIR:
 109         case FSFILT_OP_UNLINK:
 110                 /* delete one file + create/update logs for each stripe */
 111                 nblocks += EXT3_DELETE_TRANS_BLOCKS;
 112                 /*nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 113                             EXT3_SINGLEDATA_TRANS_BLOCKS) * logs;*/
 114                 break;
 115         case FSFILT_OP_RENAME:
 116                 /* modify additional directory */
 117                 nblocks += EXT3_SINGLEDATA_TRANS_BLOCKS;
 118                 /* no break */
 119         case FSFILT_OP_SYMLINK:
 120                 /* additional block + block bitmap + GDT for long symlink */
 121                 nblocks += 3;
 122                 /* no break */
 123         case FSFILT_OP_CREATE:
 124                 /* create/update logs for each stripe */
 125                 /*nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 126                             EXT3_SINGLEDATA_TRANS_BLOCKS) * logs;*/
 127                 /* no break */
 128         case FSFILT_OP_MKDIR:
 129         case FSFILT_OP_MKNOD:
 130                 /* modify one inode + block bitmap + GDT */
 131                 nblocks += 3;
 132                 /* no break */
 133         case FSFILT_OP_LINK:
 134                 /* modify parent directory */
 135                 nblocks += EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 136                         EXT3_DATA_TRANS_BLOCKS;
 137                 break;
 138         case FSFILT_OP_SETATTR:
 139                 /* Setattr on inode */
 140                 nblocks += 1;
 141                 break;
 142         case FSFILT_OP_CANCEL_UNLINK:
 143                 /* blocks for log header bitmap update OR
 144                  * blocks for catalog header bitmap update + unlink of logs */
 145                 nblocks = (LLOG_CHUNK_SIZE >> inode->i_blkbits) +
 146                         EXT3_DELETE_TRANS_BLOCKS * logs;
 147                 break;
 148         case FSFILT_OP_NOOP:
 149                 nblocks += EXT3_INDEX_EXTRA_TRANS_BLOCKS+EXT3_DATA_TRANS_BLOCKS;
 150                 break;
 151         default: CERROR("unknown transaction start op %d\n", op);
 152                 LBUG();
 153         }
 154
 155         LASSERT(current->journal_info == desc_private);
 156         journal = EXT3_SB(inode->i_sb)->s_journal;
 157         if (nblocks > journal->j_max_transaction_buffers) {
 158                 CERROR("too many credits %d for op %ux%u using %d instead\n",
 159                        nblocks, op, logs, journal->j_max_transaction_buffers);
 160                 nblocks = journal->j_max_transaction_buffers;
 161         }
 162
 163  journal_start:
 164         LASSERTF(nblocks > 0, "can't start %d credit transaction\n", nblocks);
 165         lock_24kernel();
 166         handle = journal_start(EXT3_JOURNAL(inode), nblocks);
 167         unlock_24kernel();
 168
 169         if (!IS_ERR(handle))
 170                 LASSERT(current->journal_info == handle);
 171         else
 172                 CERROR("error starting handle for op %u (%u credits): rc %ld\n",
 173                        op, nblocks, PTR_ERR(handle));
 174         return handle;
 175 }
 176
 177 /*
 178  * Calculate the number of buffer credits needed to write multiple pages in
 179  * a single ext3 transaction.  No, this shouldn't be here, but as yet ext3
 180  * doesn't have a nice API for calculating this sort of thing in advance.
 181  *
 182  * See comment above ext3_writepage_trans_blocks for details.  We assume
 183  * no data journaling is being done, but it does allow for all of the pages
 184  * being non-contiguous.  If we are guaranteed contiguous pages we could
 185  * reduce the number of (d)indirect blocks a lot.
 186  *
 187  * With N blocks per page and P pages, for each inode we have at most:
 188  * N*P indirect
 189  * min(N*P, blocksize/4 + 1) dindirect blocks
 190  * niocount tindirect
 191  *
 192  * For the entire filesystem, we have at most:
 193  * min(sum(nindir + P), ngroups) bitmap blocks (from the above)
 194  * min(sum(nindir + P), gdblocks) group descriptor blocks (from the above)
 195  * objcount inode blocks
 196  * 1 superblock
 197  * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quota files
 198  *
 199  * 1 EXT3_DATA_TRANS_BLOCKS for the last_rcvd update.
 200  */
 201 static int fsfilt_ext3_credits_needed(int objcount, struct fsfilt_objinfo *fso,
 202                                       int niocount, struct niobuf_local *nb)
 203 {
 204         struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
 205         __u64 next_indir;
 206         const int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
 207         int nbitmaps = 0, ngdblocks;
 208         int needed = objcount + 1; /* inodes + superblock */
 209         int i, j;
 210
 211         for (i = 0, j = 0; i < objcount; i++, fso++) {
 212                 /* two or more dindirect blocks in case we cross boundary */
 213                 int ndind = (long)((nb[j + fso->fso_bufcnt - 1].offset -
 214                                     nb[j].offset) >>
 215                                    sb->s_blocksize_bits) /
 216                         (EXT3_ADDR_PER_BLOCK(sb) * EXT3_ADDR_PER_BLOCK(sb));
 217                 nbitmaps += min(fso->fso_bufcnt, ndind > 0 ? ndind : 2);
 218
 219                 /* leaf, indirect, tindirect blocks for first block */
 220                 nbitmaps += blockpp + 2;
 221
 222                 j += fso->fso_bufcnt;
 223         }
 224
 225         next_indir = nb[0].offset +
 226                 (EXT3_ADDR_PER_BLOCK(sb) << sb->s_blocksize_bits);
 227         for (i = 1; i < niocount; i++) {
 228                 if (nb[i].offset >= next_indir) {
 229                         nbitmaps++;     /* additional indirect */
 230                         next_indir = nb[i].offset +
 231                                 (EXT3_ADDR_PER_BLOCK(sb)<<sb->s_blocksize_bits);
 232                 } else if (nb[i].offset != nb[i - 1].offset + sb->s_blocksize) {
 233                         nbitmaps++;     /* additional indirect */
 234                 }
 235                 nbitmaps += blockpp;    /* each leaf in different group? */
 236         }
 237
 238         ngdblocks = nbitmaps;
 239         if (nbitmaps > EXT3_SB(sb)->s_groups_count)
 240                 nbitmaps = EXT3_SB(sb)->s_groups_count;
 241         if (ngdblocks > EXT3_SB(sb)->s_gdb_count)
 242                 ngdblocks = EXT3_SB(sb)->s_gdb_count;
 243
 244         needed += nbitmaps + ngdblocks;
 245
 246         /* last_rcvd update */
 247         needed += EXT3_DATA_TRANS_BLOCKS;
 248
 249 #if defined(CONFIG_QUOTA) && !defined(__x86_64__) /* XXX */
 250         /* We assume that there will be 1 bit set in s_dquot.flags for each
 251          * quota file that is active.  This is at least true for now.
 252          */
 253         needed += hweight32(sb_any_quota_enabled(sb)) *
 254                 EXT3_SINGLEDATA_TRANS_BLOCKS;
 255 #endif
 256
 257         return needed;
 258 }
 259
 260 /* We have to start a huge journal transaction here to hold all of the
 261  * metadata for the pages being written here.  This is necessitated by
 262  * the fact that we do lots of prepare_write operations before we do
 263  * any of the matching commit_write operations, so even if we split
 264  * up to use "smaller" transactions none of them could complete until
 265  * all of them were opened.  By having a single journal transaction,
 266  * we eliminate duplicate reservations for common blocks like the
 267  * superblock and group descriptors or bitmaps.
 268  *
 269  * We will start the transaction here, but each prepare_write will
 270  * add a refcount to the transaction, and each commit_write will
 271  * remove a refcount.  The transaction will be closed when all of
 272  * the pages have been written.
 273  */
 274 static void *fsfilt_ext3_brw_start(int objcount, struct fsfilt_objinfo *fso,
 275                                    int niocount, struct niobuf_local *nb,
 276                                    void *desc_private, int logs)
 277 {
 278         journal_t *journal;
 279         handle_t *handle;
 280         int needed;
 281         ENTRY;
 282
 283         LASSERT(current->journal_info == desc_private);
 284         journal = EXT3_SB(fso->fso_dentry->d_inode->i_sb)->s_journal;
 285         needed = fsfilt_ext3_credits_needed(objcount, fso, niocount, nb);
 286
 287         /* The number of blocks we could _possibly_ dirty can very large.
 288          * We reduce our request if it is absurd (and we couldn't get that
 289          * many credits for a single handle anyways).
 290          *
 291          * At some point we have to limit the size of I/Os sent at one time,
 292          * increase the size of the journal, or we have to calculate the
 293          * actual journal requirements more carefully by checking all of
 294          * the blocks instead of being maximally pessimistic.  It remains to
 295          * be seen if this is a real problem or not.
 296          */
 297         if (needed > journal->j_max_transaction_buffers) {
 298                 CERROR("want too many journal credits (%d) using %d instead\n",
 299                        needed, journal->j_max_transaction_buffers);
 300                 needed = journal->j_max_transaction_buffers;
 301         }
 302
 303         LASSERTF(needed > 0, "can't start %d credit transaction\n", needed);
 304         lock_24kernel();
 305         handle = journal_start(journal, needed);
 306         unlock_24kernel();
 307         if (IS_ERR(handle)) {
 308                 CERROR("can't get handle for %d credits: rc = %ld\n", needed,
 309                        PTR_ERR(handle));
 310         } else {
 311                 LASSERT(handle->h_buffer_credits >= needed);
 312                 LASSERT(current->journal_info == handle);
 313         }
 314
 315         RETURN(handle);
 316 }
 317
 318 static int fsfilt_ext3_commit(struct super_block *sb, struct inode *inode,
 319                               void *h, int force_sync)
 320 {
 321         int rc;
 322         handle_t *handle = h;
 323
 324         LASSERT(current->journal_info == handle);
 325         if (force_sync)
 326                 handle->h_sync = 1; /* recovery likes this */
 327
 328         lock_24kernel();
 329         rc = journal_stop(handle);
 330         unlock_24kernel();
 331
 332         return rc;
 333 }
 334
 335 static int fsfilt_ext3_commit_async(struct inode *inode, void *h,
 336                                     void **wait_handle)
 337 {
 338         unsigned long tid;
 339         transaction_t *transaction;
 340 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 341         unsigned long rtid;
 342 #endif
 343         handle_t *handle = h;
 344         journal_t *journal;
 345         int rc;
 346
 347         LASSERT(current->journal_info == handle);
 348
 349         lock_24kernel();
 350         transaction = handle->h_transaction;
 351         journal = transaction->t_journal;
 352         tid = transaction->t_tid;
 353         /* we don't want to be blocked */
 354         handle->h_sync = 0;
 355         rc = journal_stop(handle);
 356         if (rc) {
 357                 CERROR("error while stopping transaction: %d\n", rc);
 358                 unlock_kernel();
 359                 return rc;
 360         }
 361 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 362         rtid = log_start_commit(journal, transaction);
 363         if (rtid != tid)
 364                 CERROR("strange race: %lu != %lu\n",
 365                        (unsigned long) tid, (unsigned long) rtid);
 366 #else
 367         log_start_commit(journal, tid);
 368 #endif
 369         unlock_24kernel();
 370
 371         *wait_handle = (void *) tid;
 372         CDEBUG(D_INODE, "commit async: %lu\n", (unsigned long) tid);
 373         return 0;
 374 }
 375
 376 static int fsfilt_ext3_commit_wait(struct inode *inode, void *h)
 377 {
 378         tid_t tid = (tid_t)(long)h;
 379
 380         CDEBUG(D_INODE, "commit wait: %lu\n", (unsigned long) tid);
 381         if (is_journal_aborted(EXT3_JOURNAL(inode)))
 382                 return -EIO;
 383
 384         log_wait_commit(EXT3_JOURNAL(inode), tid);
 385
 386         return 0;
 387 }
 388
 389 static int fsfilt_ext3_setattr(struct dentry *dentry, void *handle,
 390                                struct iattr *iattr, int do_trunc)
 391 {
 392         struct inode *inode = dentry->d_inode;
 393         int rc;
 394
 395         lock_24kernel();
 396
 397         /* A _really_ horrible hack to avoid removing the data stored
 398          * in the block pointers; this is really the "small" stripe MD data.
 399          * We can avoid further hackery by virtue of the MDS file size being
 400          * zero all the time (which doesn't invoke block truncate at unlink
 401          * time), so we assert we never change the MDS file size from zero. */
 402         if (iattr->ia_valid & ATTR_SIZE && !do_trunc) {
 403                 /* ATTR_SIZE would invoke truncate: clear it */
 404                 iattr->ia_valid &= ~ATTR_SIZE;
 405                 EXT3_I(inode)->i_disksize = inode->i_size = iattr->ia_size;
 406
 407                 /* make sure _something_ gets set - so new inode
 408                  * goes to disk (probably won't work over XFS */
 409                 if (!(iattr->ia_valid & (ATTR_MODE | ATTR_MTIME | ATTR_CTIME))){
 410                         iattr->ia_valid |= ATTR_MODE;
 411                         iattr->ia_mode = inode->i_mode;
 412                 }
 413         }
 414
 415         /* Don't allow setattr to change file type */
 416         iattr->ia_mode = (inode->i_mode & S_IFMT)|(iattr->ia_mode & ~S_IFMT);
 417
 418         /* We set these flags on the client, but have already checked perms
 419          * so don't confuse inode_change_ok. */
 420         iattr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET);
 421
 422         if (inode->i_op->setattr) {
 423                 rc = inode->i_op->setattr(dentry, iattr);
 424         } else {
 425                 rc = inode_change_ok(inode, iattr);
 426                 if (!rc)
 427                         rc = inode_setattr(inode, iattr);
 428         }
 429
 430         unlock_24kernel();
 431
 432         return rc;
 433 }
 434
 435 static int fsfilt_ext3_iocontrol(struct inode * inode, struct file *file,
 436                                  unsigned int cmd, unsigned long arg)
 437 {
 438         int rc = 0;
 439         ENTRY;
 440
 441         if (inode->i_fop->ioctl)
 442                 rc = inode->i_fop->ioctl(inode, file, cmd, arg);
 443         else
 444                 RETURN(-ENOTTY);
 445
 446         RETURN(rc);
 447 }
 448
 449 static int fsfilt_ext3_set_xattr(struct inode * inode, void *handle, char *name,
 450                                  void *buffer, int buffer_size)
 451 {
 452         int rc = 0;
 453
 454         lock_24kernel();
 455
 456         rc = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_TRUSTED,
 457                                    name, buffer, buffer_size, 0);
 458         unlock_24kernel();
 459         if (rc)
 460                 CERROR("set xattr %s from inode %lu: rc %d\n",
 461                        name,  inode->i_ino, rc);
 462         return rc;
 463 }
 464
 465 static int fsfilt_ext3_get_xattr(struct inode *inode, char *name,
 466                                  void *buffer, int buffer_size)
 467 {
 468         int rc = 0;
 469
 470         lock_24kernel();
 471
 472         rc = ext3_xattr_get(inode, EXT3_XATTR_INDEX_TRUSTED,
 473                             name, buffer, buffer_size);
 474         unlock_24kernel();
 475
 476         if (buffer == NULL)
 477                 return (rc == -ENODATA) ? 0 : rc;
 478         if (rc < 0) {
 479                 CDEBUG(D_INFO, "error getting EA %s from inode %lu: rc %d\n",
 480                        name,  inode->i_ino, rc);
 481                 memset(buffer, 0, buffer_size);
 482                 return (rc == -ENODATA) ? 0 : rc;
 483         }
 484
 485         return rc;
 486 }
 487
 488 static int fsfilt_ext3_set_md(struct inode *inode, void *handle,
 489                               void *lmm, int lmm_size,
 490                               enum ea_type type)
 491 {
 492         int rc;
 493
 494         switch(type) {
 495         case EA_LOV:
 496                 rc = fsfilt_ext3_set_xattr(inode, handle,
 497                                            XATTR_LUSTRE_MDS_LOV_EA,
 498                                            lmm, lmm_size);
 499                 break;
 500         case EA_MEA:
 501                 rc = fsfilt_ext3_set_xattr(inode, handle,
 502                                            XATTR_LUSTRE_MDS_MEA_EA,
 503                                            lmm, lmm_size);
 504                 break;
 505         case EA_SID:
 506                 rc = fsfilt_ext3_set_xattr(inode, handle,
 507                                            XATTR_LUSTRE_MDS_SID_EA,
 508                                            lmm, lmm_size);
 509                 break;
 510         case EA_MID:
 511                 rc = fsfilt_ext3_set_xattr(inode, handle,
 512                                            XATTR_LUSTRE_MDS_MID_EA,
 513                                            lmm, lmm_size);
 514                 break;
 515         default:
 516                 return -EINVAL;
 517         }
 518
 519         return rc;
 520 }
 521
 522 static int fsfilt_ext3_get_md(struct inode *inode, void *lmm,
 523                               int lmm_size, enum ea_type type)
 524 {
 525         int rc;
 526
 527         switch (type) {
 528         case EA_LOV:
 529                 rc = fsfilt_ext3_get_xattr(inode,
 530                                            XATTR_LUSTRE_MDS_LOV_EA,
 531                                            lmm, lmm_size);
 532                 break;
 533         case EA_MEA:
 534                 rc = fsfilt_ext3_get_xattr(inode,
 535                                            XATTR_LUSTRE_MDS_MEA_EA,
 536                                            lmm, lmm_size);
 537                 break;
 538         case EA_SID:
 539                 rc = fsfilt_ext3_get_xattr(inode,
 540                                            XATTR_LUSTRE_MDS_SID_EA,
 541                                            lmm, lmm_size);
 542                 break;
 543         case EA_MID:
 544                 rc = fsfilt_ext3_get_xattr(inode,
 545                                            XATTR_LUSTRE_MDS_MID_EA,
 546                                            lmm, lmm_size);
 547                 break;
 548         default:
 549                 return -EINVAL;
 550         }
 551
 552         return rc;
 553 }
 554
 555 static int fsfilt_ext3_send_bio(int rw, struct inode *inode, void *bio)
 556 {
 557         int rc = 0;
 558 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
 559         submit_bio(rw, (struct bio *)bio);
 560 #else
 561         struct bio *b = (struct kiobuf *)bio;
 562         int blocks_per_page;
 563
 564         rc = brw_kiovec(rw, 1, &b, inode->i_dev,
 565                         b->blocks, 1 << inode->i_blkbits);
 566
 567         blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 568
 569         if (rc != (1 << inode->i_blkbits) * b->nr_pages * blocks_per_page) {
 570                 CERROR("short write?  expected %d, wrote %d\n",
 571                        (1 << inode->i_blkbits) * b->nr_pages *
 572                        blocks_per_page, rc);
 573         }
 574 #endif
 575         return rc;
 576 }
 577
 578 static struct page *fsfilt_ext3_getpage(struct inode *inode, long int index)
 579 {
 580         int rc;
 581         struct page *page;
 582
 583         page = grab_cache_page(inode->i_mapping, index);
 584         if (page == NULL)
 585                 return ERR_PTR(-ENOMEM);
 586
 587         if (PageUptodate(page)) {
 588                 unlock_page(page);
 589                 return page;
 590         }
 591
 592         rc = inode->i_mapping->a_ops->readpage(NULL, page);
 593         if (rc < 0) {
 594                 page_cache_release(page);
 595                 return ERR_PTR(rc);
 596         }
 597
 598         return page;
 599 }
 600
 601 static ssize_t fsfilt_ext3_readpage(struct file *file, char *buf, size_t count,
 602                                     loff_t *off)
 603 {
 604         struct inode *inode = file->f_dentry->d_inode;
 605         int rc = 0;
 606
 607         if (S_ISREG(inode->i_mode))
 608                 rc = file->f_op->read(file, buf, count, off);
 609         else {
 610                 const int blkbits = inode->i_sb->s_blocksize_bits;
 611                 const int blksize = inode->i_sb->s_blocksize;
 612
 613                 CDEBUG(D_EXT2, "reading "LPSZ" at dir %lu+%llu\n",
 614                        count, inode->i_ino, *off);
 615                 while (count > 0) {
 616                         struct buffer_head *bh;
 617
 618                         bh = NULL;
 619                         if (*off < inode->i_size) {
 620                                 int err = 0;
 621
 622                                 bh = ext3_bread(NULL, inode, *off >> blkbits,
 623                                                 0, &err);
 624
 625                                 CDEBUG(D_EXT2, "read %u@%llu\n", blksize, *off);
 626
 627                                 if (bh) {
 628                                         memcpy(buf, bh->b_data, blksize);
 629                                         brelse(bh);
 630                                 } else if (err) {
 631                                         /* XXX in theory we should just fake
 632                                          * this buffer and continue like ext3,
 633                                          * especially if this is a partial read
 634                                          */
 635                                         CERROR("error read dir %lu+%llu: %d\n",
 636                                                inode->i_ino, *off, err);
 637                                         RETURN(err);
 638                                 }
 639                         }
 640                         if (!bh) {
 641                                 struct ext3_dir_entry_2 *fake = (void *)buf;
 642
 643                                 CDEBUG(D_EXT2, "fake %u@%llu\n", blksize, *off);
 644                                 memset(fake, 0, sizeof(*fake));
 645                                 fake->rec_len = cpu_to_le32(blksize);
 646                         }
 647                         count -= blksize;
 648                         buf += blksize;
 649                         *off += blksize;
 650                         rc += blksize;
 651                 }
 652         }
 653
 654         return rc;
 655 }
 656
 657 static void fsfilt_ext3_cb_func(struct journal_callback *jcb, int error)
 658 {
 659         struct fsfilt_cb_data *fcb = (struct fsfilt_cb_data *)jcb;
 660
 661         fcb->cb_func(fcb->cb_obd, fcb->cb_last_num, fcb->cb_data, error);
 662
 663         OBD_SLAB_FREE(fcb, fcb_cache, sizeof *fcb);
 664         atomic_dec(&fcb_cache_count);
 665 }
 666
 667 static int fsfilt_ext3_add_journal_cb(struct obd_device *obd,
 668                                       struct super_block *sb,
 669                                       __u64 last_num, void *handle,
 670                                       fsfilt_cb_t cb_func,
 671                                       void *cb_data)
 672 {
 673         struct fsfilt_cb_data *fcb;
 674
 675         OBD_SLAB_ALLOC(fcb, fcb_cache, GFP_NOFS, sizeof *fcb);
 676         if (fcb == NULL)
 677                 RETURN(-ENOMEM);
 678
 679         atomic_inc(&fcb_cache_count);
 680         fcb->cb_func = cb_func;
 681         fcb->cb_obd = obd;
 682         fcb->cb_last_num = last_num;
 683         fcb->cb_data = cb_data;
 684
 685         CDEBUG(D_EXT2, "set callback for last_num: "LPD64"\n", last_num);
 686         lock_24kernel();
 687         journal_callback_set(handle, fsfilt_ext3_cb_func,
 688                              (struct journal_callback *)fcb);
 689         unlock_24kernel();
 690         return 0;
 691 }
 692
 693 /*
 694  * We need to hack the return value for the free inode counts because
 695  * the current EA code requires one filesystem block per inode with EAs,
 696  * so it is possible to run out of blocks before we run out of inodes.
 697  *
 698  * This can be removed when the ext3 EA code is fixed.
 699  */
 700 static int fsfilt_ext3_statfs(struct super_block *sb, struct obd_statfs *osfs)
 701 {
 702         struct kstatfs sfs;
 703         int rc;
 704
 705         memset(&sfs, 0, sizeof(sfs));
 706
 707         rc = sb->s_op->statfs(sb, &sfs);
 708
 709         if (!rc && sfs.f_bfree < sfs.f_ffree) {
 710                 sfs.f_files = (sfs.f_files - sfs.f_ffree) + sfs.f_bfree;
 711                 sfs.f_ffree = sfs.f_bfree;
 712         }
 713
 714         statfs_pack(osfs, &sfs);
 715         return rc;
 716 }
 717
 718 static int fsfilt_ext3_sync(struct super_block *sb)
 719 {
 720         return ext3_force_commit(sb);
 721 }
 722
 723 #ifdef EXT3_MULTIBLOCK_ALLOCATOR
 724 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 725 #define ext3_up_truncate_sem(inode)  up_write(&EXT3_I(inode)->truncate_sem);
 726 #define ext3_down_truncate_sem(inode)  down_write(&EXT3_I(inode)->truncate_sem);
 727 #else
 728 #define ext3_up_truncate_sem(inode)  up(&EXT3_I(inode)->truncate_sem);
 729 #define ext3_down_truncate_sem(inode)  down(&EXT3_I(inode)->truncate_sem);
 730 #endif
 731
 732 #include <linux/lustre_version.h>
 733 #if EXT3_EXT_MAGIC == 0xf301
 734 #define ee_start e_start
 735 #define ee_block e_block
 736 #define ee_len   e_num
 737 #endif
 738 #ifndef EXT3_BB_MAX_BLOCKS
 739 #define ext3_mb_new_blocks(handle, inode, goal, count, aflags, err) \
 740         ext3_new_blocks(handle, inode, count, goal, err)
 741 #endif
 742
 743 struct bpointers {
 744         unsigned long *blocks;
 745         int *created;
 746         unsigned long start;
 747         int num;
 748         int init_num;
 749         int create;
 750 };
 751 static int ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path,
 752                                 unsigned long block, int *aflags)
 753 {
 754         struct ext3_inode_info *ei = EXT3_I(inode);
 755         unsigned long bg_start;
 756         unsigned long colour;
 757         int depth;
 758
 759         if (path) {
 760                 struct ext3_extent *ex;
 761                 depth = path->p_depth;
 762
 763                 /* try to predict block placement */
 764                 if ((ex = path[depth].p_ext)) {
 765 #if 0
 766                         /* This prefers to eat into a contiguous extent
 767                          * rather than find an extent that the whole
 768                          * request will fit into.  This can fragment data
 769                          * block allocation and prevents our lovely 1M I/Os
 770                          * from reaching the disk intact. */
 771
 772                         if (ex->ee_block + ex->ee_len == block)
 773                                 *aflags |= 1;
 774 #endif
 775                         return ex->ee_start + (block - ex->ee_block);
 776                 }
 777
 778                 /* it looks index is empty
 779                  * try to find starting from index itself */
 780                 if (path[depth].p_bh)
 781                         return path[depth].p_bh->b_blocknr;
 782         }
 783
 784         /* OK. use inode's group */
 785         bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
 786                 le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
 787         colour = (current->pid % 16) *
 788                         (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 789         return bg_start + colour + block;
 790 }
 791
 792 static int ext3_ext_new_extent_cb(struct ext3_extents_tree *tree,
 793                                   struct ext3_ext_path *path,
 794                                   struct ext3_extent *newex, int exist)
 795 {
 796         struct inode *inode = tree->inode;
 797         struct bpointers *bp = tree->private;
 798         int count, err, goal;
 799         unsigned long pblock;
 800         unsigned long tgen;
 801         loff_t new_i_size;
 802         handle_t *handle;
 803         int i, aflags = 0;
 804
 805         i = EXT_DEPTH(tree);
 806         EXT_ASSERT(i == path->p_depth);
 807         EXT_ASSERT(path[i].p_hdr);
 808
 809         if (exist) {
 810                 err = EXT_CONTINUE;
 811                 goto map;
 812         }
 813
 814         if (bp->create == 0) {
 815                 i = 0;
 816                 if (newex->ee_block < bp->start)
 817                         i = bp->start - newex->ee_block;
 818                 if (i >= newex->ee_len)
 819                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 820                                         i, newex->ee_len);
 821                 for (; i < newex->ee_len && bp->num; i++) {
 822                         *(bp->created) = 0;
 823                         bp->created++;
 824                         *(bp->blocks) = 0;
 825                         bp->blocks++;
 826                         bp->num--;
 827                         bp->start++;
 828                 }
 829
 830                 return EXT_CONTINUE;
 831         }
 832         tgen = EXT_GENERATION(tree);
 833         count = ext3_ext_calc_credits_for_insert(tree, path);
 834         ext3_up_truncate_sem(inode);
 835         lock_24kernel();
 836         handle = journal_start(EXT3_JOURNAL(inode), count + EXT3_ALLOC_NEEDED + 1);
 837         unlock_24kernel();
 838         if (IS_ERR(handle)) {
 839                 ext3_down_truncate_sem(inode);
 840                 return PTR_ERR(handle);
 841         }
 842
 843         if (tgen != EXT_GENERATION(tree)) {
 844                 /* the tree has changed. so path can be invalid at moment */
 845                 lock_24kernel();
 846                 journal_stop(handle);
 847                 unlock_24kernel();
 848                 ext3_down_truncate_sem(inode);
 849                 return EXT_REPEAT;
 850         }
 851         ext3_down_truncate_sem(inode);
 852         count = newex->ee_len;
 853         goal = ext3_ext_find_goal(inode, path, newex->ee_block, &aflags);
 854         aflags |= 2; /* block have been already reserved */
 855         pblock = ext3_mb_new_blocks(handle, inode, goal, &count, aflags, &err);
 856         if (!pblock)
 857                 goto out;
 858         EXT_ASSERT(count <= newex->ee_len);
 859
 860         /* insert new extent */
 861         newex->ee_start = pblock;
 862         newex->ee_len = count;
 863         err = ext3_ext_insert_extent(handle, tree, path, newex);
 864         if (err)
 865                 goto out;
 866
 867         /* correct on-disk inode size */
 868         if (newex->ee_len > 0) {
 869                 new_i_size = (loff_t) newex->ee_block + newex->ee_len;
 870                 new_i_size = new_i_size << inode->i_blkbits;
 871                 if (new_i_size > EXT3_I(inode)->i_disksize) {
 872                         EXT3_I(inode)->i_disksize = new_i_size;
 873                         err = ext3_mark_inode_dirty(handle, inode);
 874                 }
 875         }
 876 out:
 877         lock_24kernel();
 878         journal_stop(handle);
 879         unlock_24kernel();
 880 map:
 881         if (err >= 0) {
 882                 /* map blocks */
 883                 if (bp->num == 0) {
 884                         CERROR("hmm. why do we find this extent?\n");
 885                         CERROR("initial space: %lu:%u\n",
 886                                 bp->start, bp->init_num);
 887                         CERROR("current extent: %u/%u/%u %d\n",
 888                                 newex->ee_block, newex->ee_len,
 889                                 newex->ee_start, exist);
 890                 }
 891                 i = 0;
 892                 if (newex->ee_block < bp->start)
 893                         i = bp->start - newex->ee_block;
 894                 if (i >= newex->ee_len)
 895                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 896                                         i, newex->ee_len);
 897                 for (; i < newex->ee_len && bp->num; i++) {
 898                         *(bp->created) = (exist == 0 ? 1 : 0);
 899                         bp->created++;
 900                         *(bp->blocks) = newex->ee_start + i;
 901                         bp->blocks++;
 902                         bp->num--;
 903                         bp->start++;
 904                 }
 905         }
 906         return err;
 907 }
 908
 909 int fsfilt_map_nblocks(struct inode *inode, unsigned long block,
 910                        unsigned long num, unsigned long *blocks,
 911                        int *created, int create)
 912 {
 913         struct ext3_extents_tree tree;
 914         struct bpointers bp;
 915         int err;
 916
 917         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
 918                 block, block + num, (unsigned) inode->i_ino);
 919
 920         ext3_init_tree_desc(&tree, inode);
 921         tree.private = &bp;
 922         bp.blocks = blocks;
 923         bp.created = created;
 924         bp.start = block;
 925         bp.init_num = bp.num = num;
 926         bp.create = create;
 927
 928         ext3_down_truncate_sem(inode);
 929         err = ext3_ext_walk_space(&tree, block, num, ext3_ext_new_extent_cb);
 930         ext3_ext_invalidate_cache(&tree);
 931         ext3_up_truncate_sem(inode);
 932         return err;
 933 }
 934
 935 int fsfilt_ext3_map_ext_inode_pages(struct inode *inode, struct page **page,
 936                                     int pages, unsigned long *blocks,
 937                                     int *created, int create)
 938 {
 939         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 940         int rc = 0, i = 0;
 941         struct page *fp = NULL;
 942         int clen = 0;
 943
 944         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 945                 inode->i_ino, pages, (*page)->index);
 946
 947         /* pages are sorted already. so, we just have to find
 948          * contig. space and process them properly */
 949         while (i < pages) {
 950                 if (fp == NULL) {
 951                         /* start new extent */
 952                         fp = *page++;
 953                         clen = 1;
 954                         i++;
 955                         continue;
 956                 } else if (fp->index + clen == (*page)->index) {
 957                         /* continue the extent */
 958                         page++;
 959                         clen++;
 960                         i++;
 961                         continue;
 962                 }
 963
 964                 /* process found extent */
 965                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 966                                         clen * blocks_per_page, blocks,
 967                                         created, create);
 968                 if (rc)
 969                         GOTO(cleanup, rc);
 970
 971                 /* look for next extent */
 972                 fp = NULL;
 973                 blocks += blocks_per_page * clen;
 974                 created += blocks_per_page * clen;
 975         }
 976
 977         if (fp)
 978                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 979                                         clen * blocks_per_page, blocks,
 980                                         created, create);
 981 cleanup:
 982         return rc;
 983 }
 984 #endif
 985
 986 extern int ext3_map_inode_page(struct inode *inode, struct page *page,
 987                                unsigned long *blocks, int *created, int create);
 988 int fsfilt_ext3_map_bm_inode_pages(struct inode *inode, struct page **page,
 989                                    int pages, unsigned long *blocks,
 990                                    int *created, int create)
 991 {
 992         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 993         unsigned long *b;
 994         int rc = 0, i, *cr;
 995
 996         for (i = 0, cr = created, b = blocks; i < pages; i++, page++) {
 997                 rc = ext3_map_inode_page(inode, *page, b, cr, create);
 998                 if (rc) {
 999                         CERROR("ino %lu, blk %lu cr %u create %d: rc %d\n",
1000                                inode->i_ino, *b, *cr, create, rc);
1001                         break;
1002                 }
1003
1004                 b += blocks_per_page;
1005                 cr += blocks_per_page;
1006         }
1007         return rc;
1008 }
1009
1010 int fsfilt_ext3_map_inode_pages(struct inode *inode, struct page **page,
1011                                 int pages, unsigned long *blocks,
1012                                 int *created, int create,
1013                                 struct semaphore *optional_sem)
1014 {
1015         int rc;
1016 #ifdef EXT3_MULTIBLOCK_ALLOCATOR
1017         if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL) {
1018                 rc = fsfilt_ext3_map_ext_inode_pages(inode, page, pages,
1019                                                      blocks, created, create);
1020                 return rc;
1021         }
1022 #endif
1023         if (optional_sem != NULL)
1024                 down(optional_sem);
1025         rc = fsfilt_ext3_map_bm_inode_pages(inode, page, pages, blocks,
1026                                             created, create);
1027         if (optional_sem != NULL)
1028                 up(optional_sem);
1029
1030         return rc;
1031 }
1032
1033 extern int ext3_prep_san_write(struct inode *inode, long *blocks,
1034                                int nblocks, loff_t newsize);
1035 static int fsfilt_ext3_prep_san_write(struct inode *inode, long *blocks,
1036                                       int nblocks, loff_t newsize)
1037 {
1038         return ext3_prep_san_write(inode, blocks, nblocks, newsize);
1039 }
1040
1041 static int fsfilt_ext3_read_record(struct file * file, void *buf,
1042                                    int size, loff_t *offs)
1043 {
1044         struct inode *inode = file->f_dentry->d_inode;
1045         unsigned long block;
1046         struct buffer_head *bh;
1047         int err, blocksize, csize, boffs;
1048
1049         /* prevent reading after eof */
1050         lock_kernel();
1051         if (inode->i_size < *offs + size) {
1052                 size = inode->i_size - *offs;
1053                 unlock_kernel();
1054                 if (size < 0) {
1055                         CERROR("size %llu is too short for read %u@%llu\n",
1056                                inode->i_size, size, *offs);
1057                         return -EIO;
1058                 } else if (size == 0) {
1059                         return 0;
1060                 }
1061         } else {
1062                 unlock_kernel();
1063         }
1064
1065         blocksize = 1 << inode->i_blkbits;
1066
1067         while (size > 0) {
1068                 block = *offs >> inode->i_blkbits;
1069                 boffs = *offs & (blocksize - 1);
1070                 csize = min(blocksize - boffs, size);
1071                 bh = ext3_bread(NULL, inode, block, 0, &err);
1072                 if (!bh) {
1073                         CERROR("can't read block: %d\n", err);
1074                         return err;
1075                 }
1076
1077                 memcpy(buf, bh->b_data + boffs, csize);
1078                 brelse(bh);
1079
1080                 *offs += csize;
1081                 buf += csize;
1082                 size -= csize;
1083         }
1084         return 0;
1085 }
1086
1087 static int fsfilt_ext3_write_record(struct file *file, void *buf, int bufsize,
1088                                     loff_t *offs, int force_sync)
1089 {
1090         struct buffer_head *bh = NULL;
1091         unsigned long block;
1092         struct inode *inode = file->f_dentry->d_inode;
1093         loff_t old_size = inode->i_size, offset = *offs;
1094         loff_t new_size = inode->i_size;
1095         journal_t *journal;
1096         handle_t *handle;
1097         int err = 0, block_count = 0, blocksize, size, boffs;
1098
1099         /* Determine how many transaction credits are needed */
1100         blocksize = 1 << inode->i_blkbits;
1101         block_count = (*offs & (blocksize - 1)) + bufsize;
1102         block_count = (block_count + blocksize - 1) >> inode->i_blkbits;
1103
1104         journal = EXT3_SB(inode->i_sb)->s_journal;
1105         lock_24kernel();
1106         handle = journal_start(journal,
1107                                block_count * EXT3_DATA_TRANS_BLOCKS + 2);
1108         unlock_24kernel();
1109         if (IS_ERR(handle)) {
1110                 CERROR("can't start transaction\n");
1111                 return PTR_ERR(handle);
1112         }
1113
1114         while (bufsize > 0) {
1115                 if (bh != NULL)
1116                         brelse(bh);
1117
1118                 block = offset >> inode->i_blkbits;
1119                 boffs = offset & (blocksize - 1);
1120                 size = min(blocksize - boffs, bufsize);
1121                 bh = ext3_bread(handle, inode, block, 1, &err);
1122                 if (!bh) {
1123                         CERROR("can't read/create block: %d\n", err);
1124                         goto out;
1125                 }
1126
1127                 err = ext3_journal_get_write_access(handle, bh);
1128                 if (err) {
1129                         CERROR("journal_get_write_access() returned error %d\n",
1130                                err);
1131                         goto out;
1132                 }
1133                 LASSERT(bh->b_data + boffs + size <= bh->b_data + bh->b_size);
1134                 memcpy(bh->b_data + boffs, buf, size);
1135                 err = ext3_journal_dirty_metadata(handle, bh);
1136                 if (err) {
1137                         CERROR("journal_dirty_metadata() returned error %d\n",
1138                                err);
1139                         goto out;
1140                 }
1141                 if (offset + size > new_size)
1142                         new_size = offset + size;
1143                 offset += size;
1144                 bufsize -= size;
1145                 buf += size;
1146         }
1147
1148         if (force_sync)
1149                 handle->h_sync = 1; /* recovery likes this */
1150 out:
1151         if (bh)
1152                 brelse(bh);
1153
1154         /* correct in-core and on-disk sizes */
1155         if (new_size > inode->i_size) {
1156                 lock_kernel();
1157                 if (new_size > inode->i_size)
1158                         inode->i_size = new_size;
1159                 if (inode->i_size > EXT3_I(inode)->i_disksize)
1160                         EXT3_I(inode)->i_disksize = inode->i_size;
1161                 if (inode->i_size > old_size)
1162                         mark_inode_dirty(inode);
1163                 unlock_kernel();
1164         }
1165
1166         lock_24kernel();
1167         journal_stop(handle);
1168         unlock_24kernel();
1169
1170         if (err == 0)
1171                 *offs = offset;
1172         return err;
1173 }
1174
1175 static int fsfilt_ext3_setup(struct obd_device *obd, struct super_block *sb)
1176 {
1177 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1178         struct mds_obd *mds = &obd->u.mds;
1179 #endif
1180 #if 0
1181         EXT3_SB(sb)->dx_lock = fsfilt_ext3_dx_lock;
1182         EXT3_SB(sb)->dx_unlock = fsfilt_ext3_dx_unlock;
1183 #endif
1184 #ifdef S_PDIROPS
1185         CWARN("Enabling PDIROPS\n");
1186         set_opt(EXT3_SB(sb)->s_mount_opt, PDIROPS);
1187         sb->s_flags |= S_PDIROPS;
1188 #endif
1189         /* setup mdsnum in underlying fs */
1190 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1191         if (mds->mds_md_obd) {
1192                 struct ext3_sb_info *sbi = EXT3_SB(sb);
1193                 struct ext3_super_block *es = sbi->s_es;
1194                 handle_t *handle;
1195                 int err;
1196
1197                 if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_MDSNUM)) {
1198                         CWARN("%s: set mdsnum %d in ext3\n",
1199                               obd->obd_name, mds->mds_num);
1200                         lock_24kernel();
1201                         handle = journal_start(sbi->s_journal, 1);
1202                         unlock_24kernel();
1203                         LASSERT(!IS_ERR(handle));
1204                         err = ext3_journal_get_write_access(handle, sbi->s_sbh);
1205                         LASSERT(err == 0);
1206                         EXT3_SET_INCOMPAT_FEATURE(sb,
1207                                                 EXT3_FEATURE_INCOMPAT_MDSNUM);
1208                         es->s_mdsnum = mds->mds_num;
1209                         err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
1210                         LASSERT(err == 0);
1211                         lock_24kernel();
1212                         journal_stop(handle);
1213                         unlock_24kernel();
1214                 } else {
1215                         CWARN("%s: mdsnum initialized to %u in ext3fs\n",
1216                                 obd->obd_name, es->s_mdsnum);
1217                 }
1218                 sbi->s_mdsnum = es->s_mdsnum;
1219         }
1220 #endif
1221         return 0;
1222 }
1223
1224 extern int ext3_add_dir_entry(struct dentry *dentry);
1225 extern int ext3_del_dir_entry(struct dentry *dentry);
1226
1227 static int fsfilt_ext3_add_dir_entry(struct obd_device *obd,
1228                                      struct dentry *parent,
1229                                      char *name, int namelen,
1230                                      unsigned long ino,
1231                                      unsigned long generation,
1232                                      unsigned long mds,
1233                                      unsigned long fid)
1234 {
1235 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1236         struct dentry *dentry;
1237         int err;
1238         LASSERT(ino != 0);
1239         LASSERT(namelen != 0);
1240         dentry = ll_lookup_one_len(name, parent, namelen);
1241         if (IS_ERR(dentry)) {
1242                 CERROR("can't lookup %*s in %lu/%lu: %d\n", dentry->d_name.len,
1243                        dentry->d_name.name, dentry->d_inode->i_ino,
1244                        (unsigned long) dentry->d_inode->i_generation,
1245                        (int) PTR_ERR(dentry));
1246                 RETURN(PTR_ERR(dentry));
1247         }
1248         if (dentry->d_inode != NULL || dentry->d_flags & DCACHE_CROSS_REF) {
1249                 CERROR("dentry %*s(0x%p) found\n", dentry->d_name.len,
1250                        dentry->d_name.name, dentry);
1251                 l_dput(dentry);
1252                 RETURN(-EEXIST);
1253         }
1254
1255         /* mds_reint_rename() may use this method to add dir entry
1256          * that points onto local inode. and we don't want to find
1257          * it cross-ref by subsequent lookups */
1258         d_drop(dentry);
1259
1260         dentry->d_flags |= DCACHE_CROSS_REF;
1261         dentry->d_inum = ino;
1262         dentry->d_mdsnum = mds;
1263         dentry->d_generation = generation;
1264         dentry->d_fid = fid;
1265         lock_24kernel();
1266         err = ext3_add_dir_entry(dentry);
1267         unlock_24kernel();
1268
1269         l_dput(dentry);
1270
1271         RETURN(err);
1272 #else
1273 #error "rebuild kernel and lustre with ext3-mds-num patch!"
1274         LASSERT(0);
1275 #endif
1276 }
1277
1278 static int fsfilt_ext3_del_dir_entry(struct obd_device *obd,
1279                                  struct dentry *dentry)
1280 {
1281 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1282         int err;
1283         lock_24kernel();
1284         err = ext3_del_dir_entry(dentry);
1285         unlock_24kernel();
1286         if (err == 0)
1287                 d_drop(dentry);
1288         return err;
1289 #else
1290 #error "rebuild kernel and lustre with ext3-mds-num patch!"
1291         LASSERT(0);
1292 #endif
1293 }
1294
1295 /* If fso is NULL, op is FSFILT operation, otherwise op is number of fso
1296    objects. Logs is number of logfiles to update */
1297 static int fsfilt_ext3_get_op_len(int op, struct fsfilt_objinfo *fso, int logs)
1298 {
1299         if ( !fso ) {
1300                 switch(op) {
1301                 case FSFILT_OP_CREATE:
1302                                  /* directory leaf, index & indirect & EA*/
1303                         return 4 + 3 * logs;
1304                 case FSFILT_OP_UNLINK:
1305                         return 3 * logs;
1306                 }
1307         } else {
1308                 int i;
1309                 int needed = 0;
1310                 struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
1311                 int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
1312                 int addrpp = EXT3_ADDR_PER_BLOCK(sb) * blockpp;
1313                 for (i = 0; i < op; i++, fso++) {
1314                         int nblocks = fso->fso_bufcnt * blockpp;
1315                         int ndindirect = min(nblocks, addrpp + 1);
1316                         int nindir = nblocks + ndindirect + 1;
1317
1318                         needed += nindir;
1319                 }
1320                 return needed + 3 * logs;
1321         }
1322
1323         return 0;
1324 }
1325
1326
1327 #define EXTENTS_EA "write_extents"
1328 #define EXTENTS_EA_SIZE 64
1329
1330 int ext3_ext_in_ea_alloc_space(struct inode *, int, const char *, unsigned long, unsigned long);
1331 int ext3_ext_in_ea_remove_space(struct inode *, int, const char *, unsigned long, unsigned long);
1332 int ext3_ext_in_ea_get_extents(struct inode *, int, const char *, char **, int *);
1333 int ext3_ext_in_ea_get_extents_num(struct inode *, int, const char *, int *);
1334
1335 static int fsfilt_ext3_insert_extents_ea(struct inode *inode,
1336                                       unsigned long from,
1337                                       unsigned long num)
1338 {
1339         int rc = 0;
1340
1341         rc = ext3_ext_in_ea_alloc_space(inode, EXT3_XATTR_INDEX_TRUSTED,
1342                                         EXTENTS_EA, from, num);
1343         return rc;
1344 }
1345
1346 static int fsfilt_ext3_remove_extents_ea(struct inode *inode,
1347                                          unsigned long from,
1348                                          unsigned long num)
1349 {
1350         int rc = 0;
1351
1352         rc = ext3_ext_in_ea_remove_space(inode, EXT3_XATTR_INDEX_TRUSTED,
1353                                          EXTENTS_EA, from, num);
1354         return rc;
1355 }
1356
1357 extern int ext3_init_tree_in_ea(struct inode *inode, int name_index,
1358                                 const char *eaname, int size);
1359
1360 static int fsfilt_ext3_init_extents_ea(struct inode *inode)
1361 {
1362         int rc = 0;
1363
1364         rc = ext3_init_tree_in_ea(inode, EXT3_XATTR_INDEX_TRUSTED,
1365                                   EXTENTS_EA, 64);
1366         return rc;
1367 }
1368
1369 static int fsfilt_ext3_get_inode_write_extents(struct inode *inode,
1370                                          char **pbuf, int *size)
1371 {
1372         int rc = 0;
1373
1374         rc = ext3_ext_in_ea_get_extents(inode, EXT3_XATTR_INDEX_TRUSTED,
1375                                         EXTENTS_EA,  pbuf, size);
1376         return rc;
1377 }
1378
1379 static int fsfilt_ext3_get_write_extents_num(struct inode *inode, int *size)
1380 {
1381         int rc = 0;
1382
1383         rc = ext3_ext_in_ea_get_extents_num(inode, EXT3_XATTR_INDEX_TRUSTED,
1384                                             EXTENTS_EA, size);
1385         return rc;
1386 }
1387
1388 static struct fsfilt_operations fsfilt_ext3_ops = {
1389         .fs_type                    = "ext3",
1390         .fs_owner                   = THIS_MODULE,
1391         .fs_start                   = fsfilt_ext3_start,
1392         .fs_brw_start               = fsfilt_ext3_brw_start,
1393         .fs_commit                  = fsfilt_ext3_commit,
1394         .fs_commit_async            = fsfilt_ext3_commit_async,
1395         .fs_commit_wait             = fsfilt_ext3_commit_wait,
1396         .fs_setattr                 = fsfilt_ext3_setattr,
1397         .fs_iocontrol               = fsfilt_ext3_iocontrol,
1398         .fs_set_md                  = fsfilt_ext3_set_md,
1399         .fs_get_md                  = fsfilt_ext3_get_md,
1400         .fs_readpage                = fsfilt_ext3_readpage,
1401         .fs_add_journal_cb          = fsfilt_ext3_add_journal_cb,
1402         .fs_statfs                  = fsfilt_ext3_statfs,
1403         .fs_sync                    = fsfilt_ext3_sync,
1404         .fs_map_inode_pages         = fsfilt_ext3_map_inode_pages,
1405         .fs_prep_san_write          = fsfilt_ext3_prep_san_write,
1406         .fs_write_record            = fsfilt_ext3_write_record,
1407         .fs_read_record             = fsfilt_ext3_read_record,
1408         .fs_setup                   = fsfilt_ext3_setup,
1409         .fs_getpage                 = fsfilt_ext3_getpage,
1410         .fs_send_bio                = fsfilt_ext3_send_bio,
1411         .fs_set_xattr               = fsfilt_ext3_set_xattr,
1412         .fs_get_xattr               = fsfilt_ext3_get_xattr,
1413         .fs_get_op_len              = fsfilt_ext3_get_op_len,
1414         .fs_add_dir_entry           = fsfilt_ext3_add_dir_entry,
1415         .fs_del_dir_entry           = fsfilt_ext3_del_dir_entry,
1416         .fs_init_extents_ea         = fsfilt_ext3_init_extents_ea,
1417         .fs_insert_extents_ea       = fsfilt_ext3_insert_extents_ea,
1418         .fs_remove_extents_ea       = fsfilt_ext3_remove_extents_ea,
1419         .fs_get_inode_write_extents = fsfilt_ext3_get_inode_write_extents,
1420         .fs_get_write_extents_num   = fsfilt_ext3_get_write_extents_num,
1421 };
1422
1423 static int __init fsfilt_ext3_init(void)
1424 {
1425         int rc;
1426
1427         fcb_cache = kmem_cache_create("fsfilt_ext3_fcb",
1428                                       sizeof(struct fsfilt_cb_data), 0,
1429                                       0, NULL, NULL);
1430         if (!fcb_cache) {
1431                 CERROR("error allocating fsfilt journal callback cache\n");
1432                 GOTO(out, rc = -ENOMEM);
1433         }
1434
1435         rc = fsfilt_register_ops(&fsfilt_ext3_ops);
1436
1437         if (rc)
1438                 kmem_cache_destroy(fcb_cache);
1439 out:
1440         return rc;
1441 }
1442
1443 static void __exit fsfilt_ext3_exit(void)
1444 {
1445         fsfilt_unregister_ops(&fsfilt_ext3_ops);
1446         LASSERTF(kmem_cache_destroy(fcb_cache) == 0,
1447                  "can't free fsfilt callback cache: count %d\n",
1448                  atomic_read(&fcb_cache_count));
1449 }
1450
1451 module_init(fsfilt_ext3_init);
1452 module_exit(fsfilt_ext3_exit);
1453
1454 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
1455 MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1");
1456 MODULE_LICENSE("GPL");