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 <linux/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 static kmem_cache_t *fcb_cache;
  56 static atomic_t fcb_cache_count = ATOMIC_INIT(0);
  57
  58 struct fsfilt_cb_data {
  59         struct journal_callback cb_jcb; /* jbd private data - MUST BE FIRST */
  60         fsfilt_cb_t cb_func;            /* MDS/OBD completion function */
  61         struct obd_device *cb_obd;      /* MDS/OBD completion device */
  62         __u64 cb_last_num;              /* MDS/OST last committed operation */
  63         void *cb_data;                  /* MDS/OST completion function data */
  64 };
  65
  66 #ifndef EXT3_XATTR_INDEX_TRUSTED        /* temporary until we hit l28 kernel */
  67 #define EXT3_XATTR_INDEX_TRUSTED        4
  68 #endif
  69
  70 #define XATTR_LUSTRE_MDS_LOV_EA         "lov"
  71 #define XATTR_LUSTRE_MDS_MID_EA         "mid"
  72 #define XATTR_LUSTRE_MDS_SID_EA         "sid"
  73
  74 /*
  75  * We don't currently need any additional blocks for rmdir and
  76  * unlink transactions because we are storing the OST oa_id inside
  77  * the inode (which we will be changing anyways as part of this
  78  * transaction).
  79  */
  80 static void *fsfilt_ext3_start(struct inode *inode, int op, void *desc_private,
  81                                int logs)
  82 {
  83         /* For updates to the last recieved file */
  84         int nblocks = EXT3_SINGLEDATA_TRANS_BLOCKS;
  85         journal_t *journal;
  86         void *handle;
  87
  88         if (current->journal_info) {
  89                 CDEBUG(D_INODE, "increasing refcount on %p\n",
  90                        current->journal_info);
  91                 goto journal_start;
  92         }
  93
  94         /* XXX BUG 3188 -- must return to one set of opcodes */
  95         /* FIXME - cache hook */
  96         if (op & 0x20) {
  97                 nblocks += EXT3_INDEX_EXTRA_TRANS_BLOCKS+EXT3_DATA_TRANS_BLOCKS;
  98                 op = op & ~0x20;
  99         }
 100
 101         /* FIXME - kml */
 102         if (op & 0x10) {
 103                 nblocks += EXT3_INDEX_EXTRA_TRANS_BLOCKS+EXT3_DATA_TRANS_BLOCKS;
 104                 op = op & ~0x10;
 105         }
 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         lock_kernel();
 165         handle = journal_start(EXT3_JOURNAL(inode), nblocks);
 166         unlock_kernel();
 167
 168         if (!IS_ERR(handle))
 169                 LASSERT(current->journal_info == handle);
 170         else
 171                 CERROR("error starting handle for op %u (%u credits): rc %ld\n",
 172                        op, nblocks, PTR_ERR(handle));
 173         return handle;
 174 }
 175
 176 /*
 177  * Calculate the number of buffer credits needed to write multiple pages in
 178  * a single ext3 transaction.  No, this shouldn't be here, but as yet ext3
 179  * doesn't have a nice API for calculating this sort of thing in advance.
 180  *
 181  * See comment above ext3_writepage_trans_blocks for details.  We assume
 182  * no data journaling is being done, but it does allow for all of the pages
 183  * being non-contiguous.  If we are guaranteed contiguous pages we could
 184  * reduce the number of (d)indirect blocks a lot.
 185  *
 186  * With N blocks per page and P pages, for each inode we have at most:
 187  * N*P indirect
 188  * min(N*P, blocksize/4 + 1) dindirect blocks
 189  * niocount tindirect
 190  *
 191  * For the entire filesystem, we have at most:
 192  * min(sum(nindir + P), ngroups) bitmap blocks (from the above)
 193  * min(sum(nindir + P), gdblocks) group descriptor blocks (from the above)
 194  * objcount inode blocks
 195  * 1 superblock
 196  * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quota files
 197  *
 198  * 1 EXT3_DATA_TRANS_BLOCKS for the last_rcvd update.
 199  */
 200 static int fsfilt_ext3_credits_needed(int objcount, struct fsfilt_objinfo *fso,
 201                                       int niocount, struct niobuf_local *nb)
 202 {
 203         struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
 204         __u64 next_indir;
 205         const int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
 206         int nbitmaps = 0, ngdblocks;
 207         int needed = objcount + 1; /* inodes + superblock */
 208         int i, j;
 209
 210         for (i = 0, j = 0; i < objcount; i++, fso++) {
 211                 /* two or more dindirect blocks in case we cross boundary */
 212                 int ndind = (long)((nb[j + fso->fso_bufcnt - 1].offset -
 213                                     nb[j].offset) >>
 214                                    sb->s_blocksize_bits) /
 215                         (EXT3_ADDR_PER_BLOCK(sb) * EXT3_ADDR_PER_BLOCK(sb));
 216                 nbitmaps += min(fso->fso_bufcnt, ndind > 0 ? ndind : 2);
 217
 218                 /* leaf, indirect, tindirect blocks for first block */
 219                 nbitmaps += blockpp + 2;
 220
 221                 j += fso->fso_bufcnt;
 222         }
 223
 224         next_indir = nb[0].offset +
 225                 (EXT3_ADDR_PER_BLOCK(sb) << sb->s_blocksize_bits);
 226         for (i = 1; i < niocount; i++) {
 227                 if (nb[i].offset >= next_indir) {
 228                         nbitmaps++;     /* additional indirect */
 229                         next_indir = nb[i].offset +
 230                                 (EXT3_ADDR_PER_BLOCK(sb)<<sb->s_blocksize_bits);
 231                 } else if (nb[i].offset != nb[i - 1].offset + sb->s_blocksize) {
 232                         nbitmaps++;     /* additional indirect */
 233                 }
 234                 nbitmaps += blockpp;    /* each leaf in different group? */
 235         }
 236
 237         ngdblocks = nbitmaps;
 238         if (nbitmaps > EXT3_SB(sb)->s_groups_count)
 239                 nbitmaps = EXT3_SB(sb)->s_groups_count;
 240         if (ngdblocks > EXT3_SB(sb)->s_gdb_count)
 241                 ngdblocks = EXT3_SB(sb)->s_gdb_count;
 242
 243         needed += nbitmaps + ngdblocks;
 244
 245         /* last_rcvd update */
 246         needed += EXT3_DATA_TRANS_BLOCKS;
 247
 248 #if defined(CONFIG_QUOTA) && !defined(__x86_64__) /* XXX */
 249         /* We assume that there will be 1 bit set in s_dquot.flags for each
 250          * quota file that is active.  This is at least true for now.
 251          */
 252         needed += hweight32(sb_any_quota_enabled(sb)) *
 253                 EXT3_SINGLEDATA_TRANS_BLOCKS;
 254 #endif
 255
 256         return needed;
 257 }
 258
 259 /* We have to start a huge journal transaction here to hold all of the
 260  * metadata for the pages being written here.  This is necessitated by
 261  * the fact that we do lots of prepare_write operations before we do
 262  * any of the matching commit_write operations, so even if we split
 263  * up to use "smaller" transactions none of them could complete until
 264  * all of them were opened.  By having a single journal transaction,
 265  * we eliminate duplicate reservations for common blocks like the
 266  * superblock and group descriptors or bitmaps.
 267  *
 268  * We will start the transaction here, but each prepare_write will
 269  * add a refcount to the transaction, and each commit_write will
 270  * remove a refcount.  The transaction will be closed when all of
 271  * the pages have been written.
 272  */
 273 static void *fsfilt_ext3_brw_start(int objcount, struct fsfilt_objinfo *fso,
 274                                    int niocount, struct niobuf_local *nb,
 275                                    void *desc_private, int logs)
 276 {
 277         journal_t *journal;
 278         handle_t *handle;
 279         int needed;
 280         ENTRY;
 281
 282         LASSERT(current->journal_info == desc_private);
 283         journal = EXT3_SB(fso->fso_dentry->d_inode->i_sb)->s_journal;
 284         needed = fsfilt_ext3_credits_needed(objcount, fso, niocount, nb);
 285
 286         /* The number of blocks we could _possibly_ dirty can very large.
 287          * We reduce our request if it is absurd (and we couldn't get that
 288          * many credits for a single handle anyways).
 289          *
 290          * At some point we have to limit the size of I/Os sent at one time,
 291          * increase the size of the journal, or we have to calculate the
 292          * actual journal requirements more carefully by checking all of
 293          * the blocks instead of being maximally pessimistic.  It remains to
 294          * be seen if this is a real problem or not.
 295          */
 296         if (needed > journal->j_max_transaction_buffers) {
 297                 CERROR("want too many journal credits (%d) using %d instead\n",
 298                        needed, journal->j_max_transaction_buffers);
 299                 needed = journal->j_max_transaction_buffers;
 300         }
 301
 302         lock_kernel();
 303         handle = journal_start(journal, needed);
 304         unlock_kernel();
 305         if (IS_ERR(handle)) {
 306                 CERROR("can't get handle for %d credits: rc = %ld\n", needed,
 307                        PTR_ERR(handle));
 308         } else {
 309                 LASSERT(handle->h_buffer_credits >= needed);
 310                 LASSERT(current->journal_info == handle);
 311         }
 312
 313         RETURN(handle);
 314 }
 315
 316 static int fsfilt_ext3_commit(struct super_block *sb, struct inode *inode,
 317                               void *h, int force_sync)
 318 {
 319         int rc;
 320         handle_t *handle = h;
 321
 322         LASSERT(current->journal_info == handle);
 323         if (force_sync)
 324                 handle->h_sync = 1; /* recovery likes this */
 325
 326         lock_kernel();
 327         rc = journal_stop(handle);
 328         unlock_kernel();
 329
 330         return rc;
 331 }
 332
 333 static int fsfilt_ext3_commit_async(struct inode *inode, void *h,
 334                                     void **wait_handle)
 335 {
 336         unsigned long tid;
 337         transaction_t *transaction;
 338 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 339         unsigned long rtid;
 340 #endif
 341         handle_t *handle = h;
 342         journal_t *journal;
 343         int rc;
 344
 345         LASSERT(current->journal_info == handle);
 346
 347         lock_kernel();
 348         transaction = handle->h_transaction;
 349         journal = transaction->t_journal;
 350         tid = transaction->t_tid;
 351         /* we don't want to be blocked */
 352         handle->h_sync = 0;
 353         rc = journal_stop(handle);
 354         if (rc) {
 355                 CERROR("error while stopping transaction: %d\n", rc);
 356                 unlock_kernel();
 357                 return rc;
 358         }
 359 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 360         rtid = log_start_commit(journal, transaction);
 361         if (rtid != tid)
 362                 CERROR("strange race: %lu != %lu\n",
 363                        (unsigned long) tid, (unsigned long) rtid);
 364 #else
 365         log_start_commit(journal, transaction->t_tid);
 366 #endif
 367         unlock_kernel();
 368
 369         *wait_handle = (void *) tid;
 370         CDEBUG(D_INODE, "commit async: %lu\n", (unsigned long) tid);
 371         return 0;
 372 }
 373
 374 static int fsfilt_ext3_commit_wait(struct inode *inode, void *h)
 375 {
 376         tid_t tid = (tid_t)(long)h;
 377
 378         CDEBUG(D_INODE, "commit wait: %lu\n", (unsigned long) tid);
 379         if (is_journal_aborted(EXT3_JOURNAL(inode)))
 380                 return -EIO;
 381
 382         log_wait_commit(EXT3_JOURNAL(inode), tid);
 383
 384         return 0;
 385 }
 386
 387 static int fsfilt_ext3_setattr(struct dentry *dentry, void *handle,
 388                                struct iattr *iattr, int do_trunc)
 389 {
 390         struct inode *inode = dentry->d_inode;
 391         int rc;
 392
 393         lock_kernel();
 394
 395         /* A _really_ horrible hack to avoid removing the data stored
 396          * in the block pointers; this is really the "small" stripe MD data.
 397          * We can avoid further hackery by virtue of the MDS file size being
 398          * zero all the time (which doesn't invoke block truncate at unlink
 399          * time), so we assert we never change the MDS file size from zero. */
 400         if (iattr->ia_valid & ATTR_SIZE && !do_trunc) {
 401                 /* ATTR_SIZE would invoke truncate: clear it */
 402                 iattr->ia_valid &= ~ATTR_SIZE;
 403                 EXT3_I(inode)->i_disksize = inode->i_size = iattr->ia_size;
 404
 405                 /* make sure _something_ gets set - so new inode
 406                  * goes to disk (probably won't work over XFS */
 407                 if (!(iattr->ia_valid & (ATTR_MODE | ATTR_MTIME | ATTR_CTIME))){
 408                         iattr->ia_valid |= ATTR_MODE;
 409                         iattr->ia_mode = inode->i_mode;
 410                 }
 411         }
 412
 413         /* Don't allow setattr to change file type */
 414         iattr->ia_mode = (inode->i_mode & S_IFMT)|(iattr->ia_mode & ~S_IFMT);
 415
 416         /* We set these flags on the client, but have already checked perms
 417          * so don't confuse inode_change_ok. */
 418         iattr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET);
 419
 420         if (inode->i_op->setattr) {
 421                 rc = inode->i_op->setattr(dentry, iattr);
 422         } else {
 423                 rc = inode_change_ok(inode, iattr);
 424                 if (!rc)
 425                         rc = inode_setattr(inode, iattr);
 426         }
 427
 428         unlock_kernel();
 429
 430         return rc;
 431 }
 432
 433 static int fsfilt_ext3_iocontrol(struct inode * inode, struct file *file,
 434                                  unsigned int cmd, unsigned long arg)
 435 {
 436         int rc = 0;
 437         ENTRY;
 438
 439         if (inode->i_fop->ioctl)
 440                 rc = inode->i_fop->ioctl(inode, file, cmd, arg);
 441         else
 442                 RETURN(-ENOTTY);
 443
 444         RETURN(rc);
 445 }
 446
 447 static int fsfilt_ext3_set_xattr(struct inode * inode, void *handle, char *name,
 448                                  void *buffer, int buffer_size)
 449 {
 450         int rc = 0;
 451
 452         lock_kernel();
 453
 454         rc = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_TRUSTED,
 455                                    name, buffer, buffer_size, 0);
 456         unlock_kernel();
 457         if (rc)
 458                 CERROR("set xattr %s from inode %lu: rc %d\n",
 459                        name,  inode->i_ino, rc);
 460         return rc;
 461 }
 462
 463 static int fsfilt_ext3_get_xattr(struct inode *inode, char *name,
 464                                  void *buffer, int buffer_size)
 465 {
 466         int rc = 0;
 467
 468         lock_kernel();
 469
 470         rc = ext3_xattr_get(inode, EXT3_XATTR_INDEX_TRUSTED,
 471                             name, buffer, buffer_size);
 472         unlock_kernel();
 473
 474         if (buffer == NULL)
 475                 return (rc == -ENODATA) ? 0 : rc;
 476         if (rc < 0) {
 477                 CDEBUG(D_INFO, "error getting EA %s from inode %lu: rc %d\n",
 478                        name,  inode->i_ino, rc);
 479                 memset(buffer, 0, buffer_size);
 480                 return (rc == -ENODATA) ? 0 : rc;
 481         }
 482
 483         return rc;
 484 }
 485
 486 static int fsfilt_ext3_set_md(struct inode *inode, void *handle,
 487                               void *lmm, int lmm_size)
 488 {
 489         int rc;
 490
 491         LASSERT(down_trylock(&inode->i_sem) != 0);
 492
 493         /* keep this when we get rid of OLD_EA (too noisy during conversion) */
 494         if (EXT3_I(inode)->i_file_acl /* || large inode EA flag */)
 495                 CWARN("setting EA on %lu/%u again... interesting\n",
 496                       inode->i_ino, inode->i_generation);
 497
 498         rc = fsfilt_ext3_set_xattr(inode, handle, XATTR_LUSTRE_MDS_LOV_EA,
 499                                    lmm, lmm_size);
 500         return rc;
 501 }
 502
 503 /* Must be called with i_sem held */
 504 static int fsfilt_ext3_get_md(struct inode *inode, void *lmm, int lmm_size)
 505 {
 506         int rc;
 507
 508         rc = fsfilt_ext3_get_xattr(inode, XATTR_LUSTRE_MDS_LOV_EA,
 509                                    lmm, lmm_size);
 510         return rc;
 511 }
 512
 513 static int fsfilt_ext3_set_mid(struct inode *inode, void *handle,
 514                                void *mid, int mid_size)
 515 {
 516         int rc;
 517
 518         rc = fsfilt_ext3_set_xattr(inode, handle, XATTR_LUSTRE_MDS_MID_EA,
 519                                    mid, mid_size);
 520         return rc;
 521 }
 522
 523 /* Must be called with i_sem held */
 524 static int fsfilt_ext3_get_mid(struct inode *inode, void *mid, int mid_size)
 525 {
 526         int rc;
 527
 528         rc = fsfilt_ext3_get_xattr(inode, XATTR_LUSTRE_MDS_MID_EA,
 529                                    mid, mid_size);
 530         return rc;
 531 }
 532
 533 static int fsfilt_ext3_set_sid(struct inode *inode, void *handle,
 534                                void *sid, int sid_size)
 535 {
 536         int rc;
 537
 538         rc = fsfilt_ext3_set_xattr(inode, handle, XATTR_LUSTRE_MDS_SID_EA,
 539                                    sid, sid_size);
 540         return rc;
 541 }
 542
 543 /* Must be called with i_sem held */
 544 static int fsfilt_ext3_get_sid(struct inode *inode, void *sid, int sid_size)
 545 {
 546         int rc;
 547
 548         rc = fsfilt_ext3_get_xattr(inode, XATTR_LUSTRE_MDS_SID_EA,
 549                                    sid, sid_size);
 550         return rc;
 551 }
 552
 553 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
 554 static int fsfilt_ext3_send_bio(int rw, struct inode *inode, struct bio *bio)
 555 {
 556         submit_bio(rw, bio);
 557         return 0;
 558 }
 559 #else
 560 static int fsfilt_ext3_send_bio(int rw, struct inode *inode, struct kiobuf *bio)
 561 {
 562         int rc, blocks_per_page;
 563
 564         rc = brw_kiovec(rw, 1, &bio, inode->i_dev,
 565                         bio->blocks, 1 << inode->i_blkbits);
 566
 567         blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 568
 569         if (rc != (1 << inode->i_blkbits) * bio->nr_pages * blocks_per_page) {
 570                 CERROR("short write?  expected %d, wrote %d\n",
 571                        (1 << inode->i_blkbits) * bio->nr_pages *
 572                        blocks_per_page, rc);
 573         }
 574
 575         return rc;
 576 }
 577 #endif
 578
 579 /* FIXME-UMKA: This should be used in 2.6.x io code later. */
 580 static struct page *fsfilt_ext3_getpage(struct inode *inode, long int index)
 581 {
 582         int rc;
 583         struct page *page;
 584
 585         page = grab_cache_page(inode->i_mapping, index);
 586         if (page == NULL)
 587                 return ERR_PTR(-ENOMEM);
 588
 589         if (PageUptodate(page)) {
 590                 unlock_page(page);
 591                 return page;
 592         }
 593
 594         rc = inode->i_mapping->a_ops->readpage(NULL, page);
 595         if (rc < 0) {
 596                 page_cache_release(page);
 597                 return ERR_PTR(rc);
 598         }
 599
 600         return page;
 601 }
 602
 603 static ssize_t fsfilt_ext3_readpage(struct file *file, char *buf, size_t count,
 604                                     loff_t *off)
 605 {
 606         struct inode *inode = file->f_dentry->d_inode;
 607         int rc = 0;
 608
 609         if (S_ISREG(inode->i_mode))
 610                 rc = file->f_op->read(file, buf, count, off);
 611         else {
 612                 const int blkbits = inode->i_sb->s_blocksize_bits;
 613                 const int blksize = inode->i_sb->s_blocksize;
 614
 615                 CDEBUG(D_EXT2, "reading "LPSZ" at dir %lu+%llu\n",
 616                        count, inode->i_ino, *off);
 617                 while (count > 0) {
 618                         struct buffer_head *bh;
 619
 620                         bh = NULL;
 621                         if (*off < inode->i_size) {
 622                                 int err = 0;
 623
 624                                 bh = ext3_bread(NULL, inode, *off >> blkbits,
 625                                                 0, &err);
 626
 627                                 CDEBUG(D_EXT2, "read %u@%llu\n", blksize, *off);
 628
 629                                 if (bh) {
 630                                         memcpy(buf, bh->b_data, blksize);
 631                                         brelse(bh);
 632                                 } else if (err) {
 633                                         /* XXX in theory we should just fake
 634                                          * this buffer and continue like ext3,
 635                                          * especially if this is a partial read
 636                                          */
 637                                         CERROR("error read dir %lu+%llu: %d\n",
 638                                                inode->i_ino, *off, err);
 639                                         RETURN(err);
 640                                 }
 641                         }
 642                         if (!bh) {
 643                                 struct ext3_dir_entry_2 *fake = (void *)buf;
 644
 645                                 CDEBUG(D_EXT2, "fake %u@%llu\n", blksize, *off);
 646                                 memset(fake, 0, sizeof(*fake));
 647                                 fake->rec_len = cpu_to_le32(blksize);
 648                         }
 649                         count -= blksize;
 650                         buf += blksize;
 651                         *off += blksize;
 652                         rc += blksize;
 653                 }
 654         }
 655
 656         return rc;
 657 }
 658
 659 static void fsfilt_ext3_cb_func(struct journal_callback *jcb, int error)
 660 {
 661         struct fsfilt_cb_data *fcb = (struct fsfilt_cb_data *)jcb;
 662
 663         fcb->cb_func(fcb->cb_obd, fcb->cb_last_num, fcb->cb_data, error);
 664
 665         OBD_SLAB_FREE(fcb, fcb_cache, sizeof *fcb);
 666         atomic_dec(&fcb_cache_count);
 667 }
 668
 669 static int fsfilt_ext3_add_journal_cb(struct obd_device *obd,
 670                                       struct super_block *sb,
 671                                       __u64 last_num, void *handle,
 672                                       fsfilt_cb_t cb_func,
 673                                       void *cb_data)
 674 {
 675         struct fsfilt_cb_data *fcb;
 676
 677         OBD_SLAB_ALLOC(fcb, fcb_cache, GFP_NOFS, sizeof *fcb);
 678         if (fcb == NULL)
 679                 RETURN(-ENOMEM);
 680
 681         atomic_inc(&fcb_cache_count);
 682         fcb->cb_func = cb_func;
 683         fcb->cb_obd = obd;
 684         fcb->cb_last_num = last_num;
 685         fcb->cb_data = cb_data;
 686
 687         CDEBUG(D_EXT2, "set callback for last_num: "LPD64"\n", last_num);
 688
 689         lock_kernel();
 690         journal_callback_set(handle, fsfilt_ext3_cb_func,
 691                              (struct journal_callback *)fcb);
 692         unlock_kernel();
 693
 694         return 0;
 695 }
 696
 697 /*
 698  * We need to hack the return value for the free inode counts because
 699  * the current EA code requires one filesystem block per inode with EAs,
 700  * so it is possible to run out of blocks before we run out of inodes.
 701  *
 702  * This can be removed when the ext3 EA code is fixed.
 703  */
 704 static int fsfilt_ext3_statfs(struct super_block *sb, struct obd_statfs *osfs)
 705 {
 706         struct kstatfs sfs;
 707         int rc;
 708
 709         memset(&sfs, 0, sizeof(sfs));
 710
 711         rc = sb->s_op->statfs(sb, &sfs);
 712
 713         if (!rc && sfs.f_bfree < sfs.f_ffree) {
 714                 sfs.f_files = (sfs.f_files - sfs.f_ffree) + sfs.f_bfree;
 715                 sfs.f_ffree = sfs.f_bfree;
 716         }
 717
 718         statfs_pack(osfs, &sfs);
 719         return rc;
 720 }
 721
 722 static int fsfilt_ext3_sync(struct super_block *sb)
 723 {
 724         return ext3_force_commit(sb);
 725 }
 726
 727 #ifdef EXT3_MULTIBLOCK_ALLOCATOR
 728 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
 729 #define ext3_up_truncate_sem(inode)  up_write(&EXT3_I(inode)->truncate_sem);
 730 #define ext3_down_truncate_sem(inode)  down_write(&EXT3_I(inode)->truncate_sem);
 731 #else
 732 #define ext3_up_truncate_sem(inode)  up(&EXT3_I(inode)->truncate_sem);
 733 #define ext3_down_truncate_sem(inode)  down(&EXT3_I(inode)->truncate_sem);
 734 #endif
 735
 736 #include <linux/lustre_version.h>
 737 #if EXT3_EXT_MAGIC == 0xf301
 738 #define ee_start e_start
 739 #define ee_block e_block
 740 #define ee_len   e_num
 741 #endif
 742 #ifndef EXT3_BB_MAX_BLOCKS
 743 #define ext3_mb_new_blocks(handle, inode, goal, count, aflags, err) \
 744         ext3_new_blocks(handle, inode, count, goal, err)
 745 #endif
 746
 747 struct bpointers {
 748         unsigned long *blocks;
 749         int *created;
 750         unsigned long start;
 751         int num;
 752         int init_num;
 753         int create;
 754 };
 755 static int ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path,
 756                                 unsigned long block, int *aflags)
 757 {
 758         struct ext3_inode_info *ei = EXT3_I(inode);
 759         unsigned long bg_start;
 760         unsigned long colour;
 761         int depth;
 762
 763         if (path) {
 764                 struct ext3_extent *ex;
 765                 depth = path->p_depth;
 766
 767                 /* try to predict block placement */
 768                 if ((ex = path[depth].p_ext)) {
 769                         if (ex->ee_block + ex->ee_len == block)
 770                                 *aflags |= 1;
 771                         return ex->ee_start + (block - ex->ee_block);
 772                 }
 773
 774                 /* it looks index is empty
 775                  * try to find starting from index itself */
 776                 if (path[depth].p_bh)
 777                         return path[depth].p_bh->b_blocknr;
 778         }
 779
 780         /* OK. use inode's group */
 781         bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
 782                 le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
 783         colour = (current->pid % 16) *
 784                         (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 785         return bg_start + colour + block;
 786 }
 787
 788 static int ext3_ext_new_extent_cb(struct ext3_extents_tree *tree,
 789                                   struct ext3_ext_path *path,
 790                                   struct ext3_extent *newex, int exist)
 791 {
 792         struct inode *inode = tree->inode;
 793         struct bpointers *bp = tree->private;
 794         int count, err, goal;
 795         unsigned long pblock;
 796         unsigned long tgen;
 797         loff_t new_i_size;
 798         handle_t *handle;
 799         int i, aflags = 0;
 800
 801         i = EXT_DEPTH(tree);
 802         EXT_ASSERT(i == path->p_depth);
 803         EXT_ASSERT(path[i].p_hdr);
 804
 805         if (exist) {
 806                 err = EXT_CONTINUE;
 807                 goto map;
 808         }
 809
 810         if (bp->create == 0) {
 811                 i = 0;
 812                 if (newex->ee_block < bp->start)
 813                         i = bp->start - newex->ee_block;
 814                 if (i >= newex->ee_len)
 815                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 816                                         i, newex->ee_len);
 817                 for (; i < newex->ee_len && bp->num; i++) {
 818                         *(bp->created) = 0;
 819                         bp->created++;
 820                         *(bp->blocks) = 0;
 821                         bp->blocks++;
 822                         bp->num--;
 823                         bp->start++;
 824                 }
 825
 826                 return EXT_CONTINUE;
 827         }
 828         tgen = EXT_GENERATION(tree);
 829         count = ext3_ext_calc_credits_for_insert(tree, path);
 830         ext3_up_truncate_sem(inode);
 831
 832         lock_kernel();
 833         handle = journal_start(EXT3_JOURNAL(inode), count + EXT3_ALLOC_NEEDED + 1);
 834         unlock_kernel();
 835         if (IS_ERR(handle)) {
 836                 ext3_down_truncate_sem(inode);
 837                 return PTR_ERR(handle);
 838         }
 839
 840         if (tgen != EXT_GENERATION(tree)) {
 841                 /* the tree has changed. so path can be invalid at moment */
 842                 lock_kernel();
 843                 journal_stop(handle);
 844                 unlock_kernel();
 845                 ext3_down_truncate_sem(inode);
 846                 return EXT_REPEAT;
 847         }
 848
 849         ext3_down_truncate_sem(inode);
 850         count = newex->ee_len;
 851         goal = ext3_ext_find_goal(inode, path, newex->ee_block, &aflags);
 852         aflags |= 2; /* block have been already reserved */
 853         pblock = ext3_mb_new_blocks(handle, inode, goal, &count, aflags, &err);
 854         if (!pblock)
 855                 goto out;
 856         EXT_ASSERT(count <= newex->ee_len);
 857
 858         /* insert new extent */
 859         newex->ee_start = pblock;
 860         newex->ee_len = count;
 861         err = ext3_ext_insert_extent(handle, tree, path, newex);
 862         if (err)
 863                 goto out;
 864
 865         /* correct on-disk inode size */
 866         if (newex->ee_len > 0) {
 867                 new_i_size = (loff_t) newex->ee_block + newex->ee_len;
 868                 new_i_size = new_i_size << inode->i_blkbits;
 869                 if (new_i_size > EXT3_I(inode)->i_disksize) {
 870                         EXT3_I(inode)->i_disksize = new_i_size;
 871                         err = ext3_mark_inode_dirty(handle, inode);
 872                 }
 873         }
 874 out:
 875         lock_kernel();
 876         journal_stop(handle);
 877         unlock_kernel();
 878 map:
 879         if (err >= 0) {
 880                 /* map blocks */
 881                 if (bp->num == 0) {
 882                         CERROR("hmm. why do we find this extent?\n");
 883                         CERROR("initial space: %lu:%u\n",
 884                                 bp->start, bp->init_num);
 885                         CERROR("current extent: %u/%u/%u %d\n",
 886                                 newex->ee_block, newex->ee_len,
 887                                 newex->ee_start, exist);
 888                 }
 889                 i = 0;
 890                 if (newex->ee_block < bp->start)
 891                         i = bp->start - newex->ee_block;
 892                 if (i >= newex->ee_len)
 893                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 894                                         i, newex->ee_len);
 895                 for (; i < newex->ee_len && bp->num; i++) {
 896                         *(bp->created) = (exist == 0 ? 1 : 0);
 897                         bp->created++;
 898                         *(bp->blocks) = newex->ee_start + i;
 899                         bp->blocks++;
 900                         bp->num--;
 901                         bp->start++;
 902                 }
 903         }
 904         return err;
 905 }
 906
 907 int fsfilt_map_nblocks(struct inode *inode, unsigned long block,
 908                        unsigned long num, unsigned long *blocks,
 909                        int *created, int create)
 910 {
 911         struct ext3_extents_tree tree;
 912         struct bpointers bp;
 913         int err;
 914
 915         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
 916                 block, block + num, (unsigned) inode->i_ino);
 917
 918         ext3_init_tree_desc(&tree, inode);
 919         tree.private = &bp;
 920         bp.blocks = blocks;
 921         bp.created = created;
 922         bp.start = block;
 923         bp.init_num = bp.num = num;
 924         bp.create = create;
 925
 926         ext3_down_truncate_sem(inode);
 927         err = ext3_ext_walk_space(&tree, block, num, ext3_ext_new_extent_cb);
 928         ext3_ext_invalidate_cache(&tree);
 929         ext3_up_truncate_sem(inode);
 930
 931         return err;
 932 }
 933
 934 int fsfilt_ext3_map_ext_inode_pages(struct inode *inode, struct page **page,
 935                                     int pages, unsigned long *blocks,
 936                                     int *created, int create)
 937 {
 938         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 939         int rc = 0, i = 0;
 940         struct page *fp = NULL;
 941         int clen = 0;
 942
 943         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 944                 inode->i_ino, pages, (*page)->index);
 945
 946         /* pages are sorted already. so, we just have to find
 947          * contig. space and process them properly */
 948         while (i < pages) {
 949                 if (fp == NULL) {
 950                         /* start new extent */
 951                         fp = *page++;
 952                         clen = 1;
 953                         i++;
 954                         continue;
 955                 } else if (fp->index + clen == (*page)->index) {
 956                         /* continue the extent */
 957                         page++;
 958                         clen++;
 959                         i++;
 960                         continue;
 961                 }
 962
 963                 /* process found extent */
 964                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 965                                         clen * blocks_per_page, blocks,
 966                                         created, create);
 967                 if (rc)
 968                         GOTO(cleanup, rc);
 969
 970                 /* look for next extent */
 971                 fp = NULL;
 972                 blocks += blocks_per_page * clen;
 973                 created += blocks_per_page * clen;
 974         }
 975
 976         if (fp)
 977                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 978                                         clen * blocks_per_page, blocks,
 979                                         created, create);
 980 cleanup:
 981         return rc;
 982 }
 983 #endif
 984
 985 extern int ext3_map_inode_page(struct inode *inode, struct page *page,
 986                                unsigned long *blocks, int *created, int create);
 987 int fsfilt_ext3_map_bm_inode_pages(struct inode *inode, struct page **page,
 988                                    int pages, unsigned long *blocks,
 989                                    int *created, int create)
 990 {
 991         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 992         unsigned long *b;
 993         int rc = 0, i, *cr;
 994
 995         for (i = 0, cr = created, b = blocks; i < pages; i++, page++) {
 996                 rc = ext3_map_inode_page(inode, *page, b, cr, create);
 997                 if (rc) {
 998                         CERROR("ino %lu, blk %lu cr %u create %d: rc %d\n",
 999                                inode->i_ino, *b, *cr, create, rc);
1000                         break;
1001                 }
1002
1003                 b += blocks_per_page;
1004                 cr += blocks_per_page;
1005         }
1006         return rc;
1007 }
1008
1009 int fsfilt_ext3_map_inode_pages(struct inode *inode, struct page **page,
1010                                 int pages, unsigned long *blocks,
1011                                 int *created, int create,
1012                                 struct semaphore *optional_sem)
1013 {
1014         int rc;
1015 #ifdef EXT3_MULTIBLOCK_ALLOCATOR
1016         if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL) {
1017                 rc = fsfilt_ext3_map_ext_inode_pages(inode, page, pages,
1018                                                      blocks, created, create);
1019                 return rc;
1020         }
1021 #endif
1022         if (optional_sem != NULL)
1023                 down(optional_sem);
1024         rc = fsfilt_ext3_map_bm_inode_pages(inode, page, pages, blocks,
1025                                             created, create);
1026         if (optional_sem != NULL)
1027                 up(optional_sem);
1028
1029         return rc;
1030 }
1031
1032 extern int ext3_prep_san_write(struct inode *inode, long *blocks,
1033                                int nblocks, loff_t newsize);
1034 static int fsfilt_ext3_prep_san_write(struct inode *inode, long *blocks,
1035                                       int nblocks, loff_t newsize)
1036 {
1037         return ext3_prep_san_write(inode, blocks, nblocks, newsize);
1038 }
1039
1040 static int fsfilt_ext3_read_record(struct file * file, void *buf,
1041                                    int size, loff_t *offs)
1042 {
1043         struct inode *inode = file->f_dentry->d_inode;
1044         unsigned long block;
1045         struct buffer_head *bh;
1046         int err, blocksize, csize, boffs;
1047
1048         /* prevent reading after eof */
1049         lock_kernel();
1050         if (inode->i_size < *offs + size) {
1051                 size = inode->i_size - *offs;
1052                 unlock_kernel();
1053                 if (size < 0) {
1054                         CERROR("size %llu is too short for read %u@%llu\n",
1055                                inode->i_size, size, *offs);
1056                         return -EIO;
1057                 } else if (size == 0) {
1058                         return 0;
1059                 }
1060         } else {
1061                 unlock_kernel();
1062         }
1063
1064         blocksize = 1 << inode->i_blkbits;
1065
1066         while (size > 0) {
1067                 block = *offs >> inode->i_blkbits;
1068                 boffs = *offs & (blocksize - 1);
1069                 csize = min(blocksize - boffs, size);
1070                 bh = ext3_bread(NULL, inode, block, 0, &err);
1071                 if (!bh) {
1072                         CERROR("can't read block: %d\n", err);
1073                         return err;
1074                 }
1075
1076                 memcpy(buf, bh->b_data + boffs, csize);
1077                 brelse(bh);
1078
1079                 *offs += csize;
1080                 buf += csize;
1081                 size -= csize;
1082         }
1083         return 0;
1084 }
1085
1086 static int fsfilt_ext3_write_record(struct file *file, void *buf, int bufsize,
1087                                     loff_t *offs, int force_sync)
1088 {
1089         struct buffer_head *bh = NULL;
1090         unsigned long block;
1091         struct inode *inode = file->f_dentry->d_inode;
1092         loff_t old_size = inode->i_size, offset = *offs;
1093         loff_t new_size = inode->i_size;
1094         journal_t *journal;
1095         handle_t *handle;
1096         int err = 0, block_count = 0, blocksize, size, boffs;
1097
1098         /* Determine how many transaction credits are needed */
1099         blocksize = 1 << inode->i_blkbits;
1100         block_count = (*offs & (blocksize - 1)) + bufsize;
1101         block_count = (block_count + blocksize - 1) >> inode->i_blkbits;
1102
1103         journal = EXT3_SB(inode->i_sb)->s_journal;
1104         lock_kernel();
1105         handle = journal_start(journal,
1106                                block_count * EXT3_DATA_TRANS_BLOCKS + 2);
1107         unlock_kernel();
1108         if (IS_ERR(handle)) {
1109                 CERROR("can't start transaction\n");
1110                 return PTR_ERR(handle);
1111         }
1112
1113         while (bufsize > 0) {
1114                 if (bh != NULL)
1115                         brelse(bh);
1116
1117                 block = offset >> inode->i_blkbits;
1118                 boffs = offset & (blocksize - 1);
1119                 size = min(blocksize - boffs, bufsize);
1120                 bh = ext3_bread(handle, inode, block, 1, &err);
1121                 if (!bh) {
1122                         CERROR("can't read/create block: %d\n", err);
1123                         goto out;
1124                 }
1125
1126                 err = ext3_journal_get_write_access(handle, bh);
1127                 if (err) {
1128                         CERROR("journal_get_write_access() returned error %d\n",
1129                                err);
1130                         goto out;
1131                 }
1132                 LASSERT(bh->b_data + boffs + size <= bh->b_data + bh->b_size);
1133                 memcpy(bh->b_data + boffs, buf, size);
1134                 err = ext3_journal_dirty_metadata(handle, bh);
1135                 if (err) {
1136                         CERROR("journal_dirty_metadata() returned error %d\n",
1137                                err);
1138                         goto out;
1139                 }
1140                 if (offset + size > new_size)
1141                         new_size = offset + size;
1142                 offset += size;
1143                 bufsize -= size;
1144                 buf += size;
1145         }
1146
1147         if (force_sync)
1148                 handle->h_sync = 1; /* recovery likes this */
1149 out:
1150         if (bh)
1151                 brelse(bh);
1152
1153         /* correct in-core and on-disk sizes */
1154         if (new_size > inode->i_size) {
1155                 lock_kernel();
1156                 if (new_size > inode->i_size)
1157                         inode->i_size = new_size;
1158                 if (inode->i_size > EXT3_I(inode)->i_disksize)
1159                         EXT3_I(inode)->i_disksize = inode->i_size;
1160                 if (inode->i_size > old_size)
1161                         mark_inode_dirty(inode);
1162                 unlock_kernel();
1163         }
1164
1165         lock_kernel();
1166         journal_stop(handle);
1167         unlock_kernel();
1168
1169         if (err == 0)
1170                 *offs = offset;
1171         return err;
1172 }
1173
1174 static int fsfilt_ext3_setup(struct obd_device *obd, struct super_block *sb)
1175 {
1176 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1177         struct mds_obd *mds = &obd->u.mds;
1178 #endif
1179 #if 0
1180         EXT3_SB(sb)->dx_lock = fsfilt_ext3_dx_lock;
1181         EXT3_SB(sb)->dx_unlock = fsfilt_ext3_dx_unlock;
1182 #endif
1183 #ifdef S_PDIROPS
1184         CWARN("Enabling PDIROPS\n");
1185         set_opt(EXT3_SB(sb)->s_mount_opt, PDIROPS);
1186         sb->s_flags |= S_PDIROPS;
1187 #endif
1188         /* setup mdsnum in underlying fs */
1189 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1190         if (mds->mds_lmv_obd) {
1191                 struct ext3_sb_info *sbi = EXT3_SB(sb);
1192                 struct ext3_super_block *es = sbi->s_es;
1193                 handle_t *handle;
1194                 int err;
1195
1196                 if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_MDSNUM)) {
1197                         CWARN("%s: set mdsnum %d in ext3\n",
1198                               obd->obd_name, mds->mds_num);
1199                         lock_kernel();
1200                         handle = journal_start(sbi->s_journal, 1);
1201                         unlock_kernel();
1202                         LASSERT(!IS_ERR(handle));
1203                         err = ext3_journal_get_write_access(handle, sbi->s_sbh);
1204                         LASSERT(err == 0);
1205                         EXT3_SET_INCOMPAT_FEATURE(sb,
1206                                                 EXT3_FEATURE_INCOMPAT_MDSNUM);
1207                         es->s_mdsnum = mds->mds_num;
1208                         err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
1209                         LASSERT(err == 0);
1210                         lock_kernel();
1211                         journal_stop(handle);
1212                         unlock_kernel();
1213                 } else {
1214                         CWARN("%s: mdsnum initialized to %u in ext3fs\n",
1215                                 obd->obd_name, es->s_mdsnum);
1216                 }
1217                 sbi->s_mdsnum = es->s_mdsnum;
1218         }
1219 #endif
1220         return 0;
1221 }
1222
1223 extern int ext3_add_dir_entry(struct dentry *dentry);
1224 extern int ext3_del_dir_entry(struct dentry *dentry);
1225
1226 static int fsfilt_ext3_add_dir_entry(struct obd_device *obd,
1227                                      struct dentry *parent,
1228                                      char *name, int namelen,
1229                                      unsigned long ino,
1230                                      unsigned long generation,
1231                                      unsigned long mds,
1232                                      unsigned long fid)
1233 {
1234 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1235         struct dentry *dentry;
1236         int err;
1237         LASSERT(ino != 0);
1238         LASSERT(namelen != 0);
1239         dentry = ll_lookup_one_len(name, parent, namelen);
1240         if (IS_ERR(dentry)) {
1241                 CERROR("can't lookup %*s in %lu/%lu: %d\n", dentry->d_name.len,
1242                        dentry->d_name.name, dentry->d_inode->i_ino,
1243                        (unsigned long) dentry->d_inode->i_generation,
1244                        (int) PTR_ERR(dentry));
1245                 RETURN(PTR_ERR(dentry));
1246         }
1247         if (dentry->d_inode != NULL || dentry->d_flags & DCACHE_CROSS_REF) {
1248                 CERROR("dentry %*s(0x%p) found\n", dentry->d_name.len,
1249                        dentry->d_name.name, dentry);
1250                 l_dput(dentry);
1251                 RETURN(-EEXIST);
1252         }
1253
1254         /* mds_reint_rename() may use this method to add dir entry
1255          * that points onto local inode. and we don't want to find
1256          * it cross-ref by subsequent lookups */
1257         d_drop(dentry);
1258
1259         dentry->d_flags |= DCACHE_CROSS_REF;
1260         dentry->d_inum = ino;
1261         dentry->d_mdsnum = mds;
1262         dentry->d_generation = generation;
1263         dentry->d_fid = fid;
1264         lock_kernel();
1265         err = ext3_add_dir_entry(dentry);
1266         unlock_kernel();
1267
1268         l_dput(dentry);
1269
1270         RETURN(err);
1271 #else
1272 #error "rebuild kernel and lustre with ext3-mds-num patch!"
1273         LASSERT(0);
1274 #endif
1275 }
1276
1277 static int fsfilt_ext3_del_dir_entry(struct obd_device *obd,
1278                                  struct dentry *dentry)
1279 {
1280 #ifdef EXT3_FEATURE_INCOMPAT_MDSNUM
1281         int err;
1282         lock_kernel();
1283         err = ext3_del_dir_entry(dentry);
1284         unlock_kernel();
1285         if (err == 0)
1286                 d_drop(dentry);
1287         return err;
1288 #else
1289 #error "rebuild kernel and lustre with ext3-mds-num patch!"
1290         LASSERT(0);
1291 #endif
1292 }
1293
1294 /* If fso is NULL, op is FSFILT operation, otherwise op is number of fso
1295    objects. Logs is number of logfiles to update */
1296 static int fsfilt_ext3_get_op_len(int op, struct fsfilt_objinfo *fso, int logs)
1297 {
1298         if ( !fso ) {
1299                 switch(op) {
1300                 case FSFILT_OP_CREATE:
1301                                  /* directory leaf, index & indirect & EA*/
1302                         return 4 + 3 * logs;
1303                 case FSFILT_OP_UNLINK:
1304                         return 3 * logs;
1305                 }
1306         } else {
1307                 int i;
1308                 int needed = 0;
1309                 struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
1310                 int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
1311                 int addrpp = EXT3_ADDR_PER_BLOCK(sb) * blockpp;
1312                 for (i = 0; i < op; i++, fso++) {
1313                         int nblocks = fso->fso_bufcnt * blockpp;
1314                         int ndindirect = min(nblocks, addrpp + 1);
1315                         int nindir = nblocks + ndindirect + 1;
1316
1317                         needed += nindir;
1318                 }
1319                 return needed + 3 * logs;
1320         }
1321
1322         return 0;
1323 }
1324
1325
1326 #define EXTENTS_EA "write_extents"
1327 #define EXTENTS_EA_SIZE 64
1328
1329 int ext3_ext_in_ea_alloc_space(struct inode *, int, const char *, unsigned long, unsigned long);
1330 int ext3_ext_in_ea_remove_space(struct inode *, int, const char *, unsigned long, unsigned long);
1331 int ext3_ext_in_ea_get_extents(struct inode *, int, const char *, char **, int *);
1332 int ext3_ext_in_ea_get_extents_num(struct inode *, int, const char *, int *);
1333
1334 static int fsfilt_ext3_insert_extents_ea(struct inode *inode,
1335                                       unsigned long from,
1336                                       unsigned long num)
1337 {
1338         int rc = 0;
1339
1340         rc = ext3_ext_in_ea_alloc_space(inode, EXT3_XATTR_INDEX_TRUSTED,
1341                                         EXTENTS_EA, from, num);
1342         return rc;
1343 }
1344
1345 static int fsfilt_ext3_remove_extents_ea(struct inode *inode,
1346                                          unsigned long from,
1347                                          unsigned long num)
1348 {
1349         int rc = 0;
1350
1351         rc = ext3_ext_in_ea_remove_space(inode, EXT3_XATTR_INDEX_TRUSTED,
1352                                          EXTENTS_EA, from, num);
1353         return rc;
1354 }
1355
1356 extern int ext3_init_tree_in_ea(struct inode *inode, int name_index,
1357                                 const char *eaname, int size);
1358
1359 static int fsfilt_ext3_init_extents_ea(struct inode *inode)
1360 {
1361         int rc = 0;
1362
1363         rc = ext3_init_tree_in_ea(inode, EXT3_XATTR_INDEX_TRUSTED,
1364                                   EXTENTS_EA, 64);
1365         return rc;
1366 }
1367
1368 static int fsfilt_ext3_get_inode_write_extents(struct inode *inode,
1369                                          char **pbuf, int *size)
1370 {
1371         int rc = 0;
1372
1373         rc = ext3_ext_in_ea_get_extents(inode, EXT3_XATTR_INDEX_TRUSTED,
1374                                         EXTENTS_EA,  pbuf, size);
1375         return rc;
1376 }
1377
1378 static int fsfilt_ext3_get_write_extents_num(struct inode *inode, int *size)
1379 {
1380         int rc = 0;
1381
1382         rc = ext3_ext_in_ea_get_extents_num(inode, EXT3_XATTR_INDEX_TRUSTED,
1383                                             EXTENTS_EA, size);
1384         return rc;
1385 }
1386
1387 static struct fsfilt_operations fsfilt_ext3_ops = {
1388         .fs_type                    = "ext3",
1389         .fs_owner                   = THIS_MODULE,
1390         .fs_start                   = fsfilt_ext3_start,
1391         .fs_brw_start               = fsfilt_ext3_brw_start,
1392         .fs_commit                  = fsfilt_ext3_commit,
1393         .fs_commit_async            = fsfilt_ext3_commit_async,
1394         .fs_commit_wait             = fsfilt_ext3_commit_wait,
1395         .fs_setattr                 = fsfilt_ext3_setattr,
1396         .fs_iocontrol               = fsfilt_ext3_iocontrol,
1397         .fs_set_md                  = fsfilt_ext3_set_md,
1398         .fs_get_md                  = fsfilt_ext3_get_md,
1399         .fs_set_mid                 = fsfilt_ext3_set_mid,
1400         .fs_get_mid                 = fsfilt_ext3_get_mid,
1401         .fs_set_sid                 = fsfilt_ext3_set_sid,
1402         .fs_get_sid                 = fsfilt_ext3_get_sid,
1403         .fs_readpage                = fsfilt_ext3_readpage,
1404         .fs_add_journal_cb          = fsfilt_ext3_add_journal_cb,
1405         .fs_statfs                  = fsfilt_ext3_statfs,
1406         .fs_sync                    = fsfilt_ext3_sync,
1407         .fs_map_inode_pages         = fsfilt_ext3_map_inode_pages,
1408         .fs_prep_san_write          = fsfilt_ext3_prep_san_write,
1409         .fs_write_record            = fsfilt_ext3_write_record,
1410         .fs_read_record             = fsfilt_ext3_read_record,
1411         .fs_setup                   = fsfilt_ext3_setup,
1412         .fs_getpage                 = fsfilt_ext3_getpage,
1413         .fs_send_bio                = fsfilt_ext3_send_bio,
1414         .fs_set_xattr               = fsfilt_ext3_set_xattr,
1415         .fs_get_xattr               = fsfilt_ext3_get_xattr,
1416         .fs_get_op_len              = fsfilt_ext3_get_op_len,
1417         .fs_add_dir_entry           = fsfilt_ext3_add_dir_entry,
1418         .fs_del_dir_entry           = fsfilt_ext3_del_dir_entry,
1419         .fs_init_extents_ea         = fsfilt_ext3_init_extents_ea,
1420         .fs_insert_extents_ea       = fsfilt_ext3_insert_extents_ea,
1421         .fs_remove_extents_ea       = fsfilt_ext3_remove_extents_ea,
1422         .fs_get_inode_write_extents = fsfilt_ext3_get_inode_write_extents,
1423         .fs_get_write_extents_num   = fsfilt_ext3_get_write_extents_num,
1424 };
1425
1426 static int __init fsfilt_ext3_init(void)
1427 {
1428         int rc;
1429
1430         fcb_cache = kmem_cache_create("fsfilt_ext3_fcb",
1431                                       sizeof(struct fsfilt_cb_data), 0,
1432                                       0, NULL, NULL);
1433         if (!fcb_cache) {
1434                 CERROR("error allocating fsfilt journal callback cache\n");
1435                 GOTO(out, rc = -ENOMEM);
1436         }
1437
1438         rc = fsfilt_register_ops(&fsfilt_ext3_ops);
1439
1440         if (rc)
1441                 kmem_cache_destroy(fcb_cache);
1442 out:
1443         return rc;
1444 }
1445
1446 static void __exit fsfilt_ext3_exit(void)
1447 {
1448         fsfilt_unregister_ops(&fsfilt_ext3_ops);
1449         LASSERTF(kmem_cache_destroy(fcb_cache) == 0,
1450                  "can't free fsfilt callback cache: count %d\n",
1451                  atomic_read(&fcb_cache_count));
1452 }
1453
1454 module_init(fsfilt_ext3_init);
1455 module_exit(fsfilt_ext3_exit);
1456
1457 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
1458 MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1");
1459 MODULE_LICENSE("GPL");