lustre/lvfs/fsfilt_ext3.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/lvfs/fsfilt_ext3.c
  37  *
  38  * Author: Andreas Dilger <adilger@clusterfs.com>
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_FILTER
  42
  43 #include <linux/init.h>
  44 #include <linux/module.h>
  45 #include <linux/fs.h>
  46 #include <linux/slab.h>
  47 #include <linux/pagemap.h>
  48 #include <ldiskfs/ldiskfs_config.h>
  49 #include <ext4/ext4.h>
  50 #include <ext4/ext4_jbd2.h>
  51 #include <linux/version.h>
  52 #include <linux/bitops.h>
  53 #include <linux/quota.h>
  54
  55 #include <libcfs/libcfs.h>
  56 #include <lustre_fsfilt.h>
  57 #include <obd.h>
  58 #include <linux/lustre_compat25.h>
  59 #include <linux/lprocfs_status.h>
  60
  61 #include <ext4/ext4_extents.h>
  62
  63 /* for kernels 2.6.18 and later */
  64 #define FSFILT_SINGLEDATA_TRANS_BLOCKS(sb) EXT3_SINGLEDATA_TRANS_BLOCKS(sb)
  65
  66 #define fsfilt_ext3_ext_insert_extent(handle, inode, path, newext, flag) \
  67                ext3_ext_insert_extent(handle, inode, path, newext, flag)
  68
  69 #define ext3_mb_discard_inode_preallocations(inode) \
  70                  ext3_discard_preallocations(inode)
  71
  72 #define fsfilt_log_start_commit(journal, tid) jbd2_log_start_commit(journal, tid)
  73 #define fsfilt_log_wait_commit(journal, tid) jbd2_log_wait_commit(journal, tid)
  74
  75 static cfs_mem_cache_t *fcb_cache;
  76
  77 struct fsfilt_cb_data {
  78         struct ext4_journal_cb_entry cb_jcb; /* private data - MUST BE FIRST */
  79         fsfilt_cb_t cb_func;            /* MDS/OBD completion function */
  80         struct obd_device *cb_obd;      /* MDS/OBD completion device */
  81         __u64 cb_last_rcvd;             /* MDS/OST last committed operation */
  82         void *cb_data;                  /* MDS/OST completion function data */
  83 };
  84
  85 static char *fsfilt_ext3_get_label(struct super_block *sb)
  86 {
  87         return EXT3_SB(sb)->s_es->s_volume_name;
  88 }
  89
  90 /* kernel has ext4_blocks_for_truncate since linux-3.1.1 */
  91 #ifdef HAVE_BLOCKS_FOR_TRUNCATE
  92 # include <ext4/truncate.h>
  93 #else
  94 static inline unsigned long ext4_blocks_for_truncate(struct inode *inode)
  95 {
  96         ext4_lblk_t needed;
  97
  98         needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
  99         if (needed < 2)
 100                 needed = 2;
 101         if (needed > EXT4_MAX_TRANS_DATA)
 102                 needed = EXT4_MAX_TRANS_DATA;
 103         return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
 104 }
 105 #endif
 106
 107 /*
 108  * We don't currently need any additional blocks for rmdir and
 109  * unlink transactions because we are storing the OST oa_id inside
 110  * the inode (which we will be changing anyways as part of this
 111  * transaction).
 112  */
 113 static void *fsfilt_ext3_start(struct inode *inode, int op, void *desc_private,
 114                                int logs)
 115 {
 116         /* For updates to the last received file */
 117         int nblocks = FSFILT_SINGLEDATA_TRANS_BLOCKS(inode->i_sb);
 118         journal_t *journal;
 119         void *handle;
 120
 121         if (current->journal_info) {
 122                 CDEBUG(D_INODE, "increasing refcount on %p\n",
 123                        current->journal_info);
 124                 goto journal_start;
 125         }
 126
 127         switch(op) {
 128         case FSFILT_OP_UNLINK:
 129                 /* delete one file + create/update logs for each stripe */
 130                 nblocks += EXT3_DELETE_TRANS_BLOCKS(inode->i_sb);
 131                 nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 132                             FSFILT_SINGLEDATA_TRANS_BLOCKS(inode->i_sb)) * logs;
 133                 break;
 134         case FSFILT_OP_CANCEL_UNLINK:
 135                 LASSERT(logs == 1);
 136
 137                 /* blocks for log header bitmap update OR
 138                  * blocks for catalog header bitmap update + unlink of logs +
 139                  * blocks for delete the inode (include blocks truncating). */
 140                 nblocks = (LLOG_CHUNK_SIZE >> inode->i_blkbits) +
 141                           EXT3_DELETE_TRANS_BLOCKS(inode->i_sb) +
 142                           ext4_blocks_for_truncate(inode) + 3;
 143                 break;
 144         default: CERROR("unknown transaction start op %d\n", op);
 145                 LBUG();
 146         }
 147
 148         LASSERT(current->journal_info == desc_private);
 149         journal = EXT3_SB(inode->i_sb)->s_journal;
 150         if (nblocks > journal->j_max_transaction_buffers) {
 151                 CWARN("too many credits %d for op %ux%u using %d instead\n",
 152                        nblocks, op, logs, journal->j_max_transaction_buffers);
 153                 nblocks = journal->j_max_transaction_buffers;
 154         }
 155
 156  journal_start:
 157         LASSERTF(nblocks > 0, "can't start %d credit transaction\n", nblocks);
 158         handle = ext3_journal_start(inode, nblocks);
 159
 160         if (!IS_ERR(handle))
 161                 LASSERT(current->journal_info == handle);
 162         else
 163                 CERROR("error starting handle for op %u (%u credits): rc %ld\n",
 164                        op, nblocks, PTR_ERR(handle));
 165         return handle;
 166 }
 167
 168 static int fsfilt_ext3_commit(struct inode *inode, void *h, int force_sync)
 169 {
 170         int rc;
 171         handle_t *handle = h;
 172
 173         LASSERT(current->journal_info == handle);
 174         if (force_sync)
 175                 handle->h_sync = 1; /* recovery likes this */
 176
 177         rc = ext3_journal_stop(handle);
 178
 179         return rc;
 180 }
 181
 182 #ifndef EXT3_EXTENTS_FL
 183 #define EXT3_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 184 #endif
 185
 186 #ifndef EXT_ASSERT
 187 #define EXT_ASSERT(cond)  BUG_ON(!(cond))
 188 #endif
 189
 190 #define EXT_GENERATION(inode)           (EXT4_I(inode)->i_ext_generation)
 191 #define ext3_ext_base                   inode
 192 #define ext3_ext_base2inode(inode)      (inode)
 193 #define EXT_DEPTH(inode)                ext_depth(inode)
 194 #define fsfilt_ext3_ext_walk_space(inode, block, num, cb, cbdata) \
 195                         ext3_ext_walk_space(inode, block, num, cb, cbdata);
 196
 197 struct bpointers {
 198         unsigned long *blocks;
 199         unsigned long start;
 200         int num;
 201         int init_num;
 202         int create;
 203 };
 204
 205 static long ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path,
 206                                unsigned long block, int *aflags)
 207 {
 208         struct ext3_inode_info *ei = EXT3_I(inode);
 209         unsigned long bg_start;
 210         unsigned long colour;
 211         int depth;
 212
 213         if (path) {
 214                 struct ext3_extent *ex;
 215                 depth = path->p_depth;
 216
 217                 /* try to predict block placement */
 218                 if ((ex = path[depth].p_ext))
 219                         return ext_pblock(ex) + (block - le32_to_cpu(ex->ee_block));
 220
 221                 /* it looks index is empty
 222                  * try to find starting from index itself */
 223                 if (path[depth].p_bh)
 224                         return path[depth].p_bh->b_blocknr;
 225         }
 226
 227         /* OK. use inode's group */
 228         bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
 229                 le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
 230         colour = (current->pid % 16) *
 231                 (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 232         return bg_start + colour + block;
 233 }
 234
 235 #define ll_unmap_underlying_metadata(sb, blocknr) \
 236         unmap_underlying_metadata((sb)->s_bdev, blocknr)
 237
 238 #ifndef EXT3_MB_HINT_GROUP_ALLOC
 239 static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base,
 240                                 struct ext3_ext_path *path, unsigned long block,
 241                                 unsigned long *count, int *err)
 242 {
 243         unsigned long pblock, goal;
 244         int aflags = 0;
 245         struct inode *inode = ext3_ext_base2inode(base);
 246
 247         goal = ext3_ext_find_goal(inode, path, block, &aflags);
 248         aflags |= 2; /* block have been already reserved */
 249         pblock = ext3_mb_new_blocks(handle, inode, goal, count, aflags, err);
 250         return pblock;
 251
 252 }
 253 #else
 254 static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base,
 255                                 struct ext3_ext_path *path, unsigned long block,
 256                                 unsigned long *count, int *err)
 257 {
 258         struct inode *inode = ext3_ext_base2inode(base);
 259         struct ext3_allocation_request ar;
 260         unsigned long pblock;
 261         int aflags;
 262
 263         /* find neighbour allocated blocks */
 264         ar.lleft = block;
 265         *err = ext3_ext_search_left(base, path, &ar.lleft, &ar.pleft);
 266         if (*err)
 267                 return 0;
 268         ar.lright = block;
 269         *err = ext3_ext_search_right(base, path, &ar.lright, &ar.pright);
 270         if (*err)
 271                 return 0;
 272
 273         /* allocate new block */
 274         ar.goal = ext3_ext_find_goal(inode, path, block, &aflags);
 275         ar.inode = inode;
 276         ar.logical = block;
 277         ar.len = *count;
 278         ar.flags = EXT3_MB_HINT_DATA;
 279         pblock = ext3_mb_new_blocks(handle, &ar, err);
 280         *count = ar.len;
 281         return pblock;
 282 }
 283 #endif
 284
 285 static int ext3_ext_new_extent_cb(struct ext3_ext_base *base,
 286                                   struct ext3_ext_path *path,
 287                                   struct ext3_ext_cache *cex,
 288 #ifdef HAVE_EXT_PREPARE_CB_EXTENT
 289                                    struct ext3_extent *ex,
 290 #endif
 291                                   void *cbdata)
 292 {
 293         struct bpointers *bp = cbdata;
 294         struct inode *inode = ext3_ext_base2inode(base);
 295         struct ext3_extent nex;
 296         unsigned long pblock;
 297         unsigned long tgen;
 298         int err, i;
 299         unsigned long count;
 300         handle_t *handle;
 301
 302 #ifdef EXT3_EXT_CACHE_EXTENT
 303         if (cex->ec_type == EXT3_EXT_CACHE_EXTENT)
 304 #else
 305         if ((cex->ec_len != 0) && (cex->ec_start != 0))
 306 #endif
 307                                                    {
 308                 err = EXT_CONTINUE;
 309                 goto map;
 310         }
 311
 312         if (bp->create == 0) {
 313                 i = 0;
 314                 if (cex->ec_block < bp->start)
 315                         i = bp->start - cex->ec_block;
 316                 if (i >= cex->ec_len)
 317                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 318                                         i, cex->ec_len);
 319                 for (; i < cex->ec_len && bp->num; i++) {
 320                         *(bp->blocks) = 0;
 321                         bp->blocks++;
 322                         bp->num--;
 323                         bp->start++;
 324                 }
 325
 326                 return EXT_CONTINUE;
 327         }
 328
 329         tgen = EXT_GENERATION(base);
 330         count = ext3_ext_calc_credits_for_insert(base, path);
 331
 332         handle = ext3_journal_start(inode, count+EXT3_ALLOC_NEEDED+1);
 333         if (IS_ERR(handle)) {
 334                 return PTR_ERR(handle);
 335         }
 336
 337         if (tgen != EXT_GENERATION(base)) {
 338                 /* the tree has changed. so path can be invalid at moment */
 339                 ext3_journal_stop(handle);
 340                 return EXT_REPEAT;
 341         }
 342
 343         /* In 2.6.32 kernel, ext4_ext_walk_space()'s callback func is not
 344          * protected by i_data_sem as whole. so we patch it to store
 345          * generation to path and now verify the tree hasn't changed */
 346         down_write((&EXT4_I(inode)->i_data_sem));
 347
 348         /* validate extent, make sure the extent tree does not changed */
 349         if (EXT_GENERATION(base) != path[0].p_generation) {
 350                 /* cex is invalid, try again */
 351                 up_write(&EXT4_I(inode)->i_data_sem);
 352                 ext3_journal_stop(handle);
 353                 return EXT_REPEAT;
 354         }
 355
 356         count = cex->ec_len;
 357         pblock = new_blocks(handle, base, path, cex->ec_block, &count, &err);
 358         if (!pblock)
 359                 goto out;
 360         EXT_ASSERT(count <= cex->ec_len);
 361
 362         /* insert new extent */
 363         nex.ee_block = cpu_to_le32(cex->ec_block);
 364         ext3_ext_store_pblock(&nex, pblock);
 365         nex.ee_len = cpu_to_le16(count);
 366         err = fsfilt_ext3_ext_insert_extent(handle, base, path, &nex, 0);
 367         if (err) {
 368                 /* free data blocks we just allocated */
 369                 /* not a good idea to call discard here directly,
 370                  * but otherwise we'd need to call it every free() */
 371 #ifdef EXT3_MB_HINT_GROUP_ALLOC
 372                 ext3_mb_discard_inode_preallocations(inode);
 373 #endif
 374                 ext3_free_blocks(handle, inode, ext_pblock(&nex),
 375                                  cpu_to_le16(nex.ee_len), 0);
 376                 goto out;
 377         }
 378
 379         /*
 380          * Putting len of the actual extent we just inserted,
 381          * we are asking ext3_ext_walk_space() to continue
 382          * scaning after that block
 383          */
 384         cex->ec_len = le16_to_cpu(nex.ee_len);
 385         cex->ec_start = ext_pblock(&nex);
 386         BUG_ON(le16_to_cpu(nex.ee_len) == 0);
 387         BUG_ON(le32_to_cpu(nex.ee_block) != cex->ec_block);
 388
 389 out:
 390         up_write((&EXT4_I(inode)->i_data_sem));
 391         ext3_journal_stop(handle);
 392 map:
 393         if (err >= 0) {
 394                 /* map blocks */
 395                 if (bp->num == 0) {
 396                         CERROR("hmm. why do we find this extent?\n");
 397                         CERROR("initial space: %lu:%u\n",
 398                                 bp->start, bp->init_num);
 399 #ifdef EXT3_EXT_CACHE_EXTENT
 400                         CERROR("current extent: %u/%u/%llu %d\n",
 401                                 cex->ec_block, cex->ec_len,
 402                                 (unsigned long long)cex->ec_start,
 403                                 cex->ec_type);
 404 #else
 405                         CERROR("current extent: %u/%u/%llu\n",
 406                                 cex->ec_block, cex->ec_len,
 407                                 (unsigned long long)cex->ec_start);
 408 #endif
 409                 }
 410                 i = 0;
 411                 if (cex->ec_block < bp->start)
 412                         i = bp->start - cex->ec_block;
 413                 if (i >= cex->ec_len)
 414                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 415                                         i, cex->ec_len);
 416                 for (; i < cex->ec_len && bp->num; i++) {
 417                         *(bp->blocks) = cex->ec_start + i;
 418 #ifdef EXT3_EXT_CACHE_EXTENT
 419                         if (cex->ec_type != EXT3_EXT_CACHE_EXTENT)
 420 #else
 421                         if ((cex->ec_len == 0) || (cex->ec_start == 0))
 422 #endif
 423                                                                         {
 424                                 /* unmap any possible underlying metadata from
 425                                  * the block device mapping.  bug 6998. */
 426                                 ll_unmap_underlying_metadata(inode->i_sb,
 427                                                              *(bp->blocks));
 428                         }
 429                         bp->blocks++;
 430                         bp->num--;
 431                         bp->start++;
 432                 }
 433         }
 434         return err;
 435 }
 436
 437 int fsfilt_map_nblocks(struct inode *inode, unsigned long block,
 438                        unsigned long num, unsigned long *blocks,
 439                        int create)
 440 {
 441         struct ext3_ext_base *base = inode;
 442         struct bpointers bp;
 443         int err;
 444
 445         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
 446                block, block + num - 1, (unsigned) inode->i_ino);
 447
 448         bp.blocks = blocks;
 449         bp.start = block;
 450         bp.init_num = bp.num = num;
 451         bp.create = create;
 452
 453         err = fsfilt_ext3_ext_walk_space(base, block, num,
 454                                          ext3_ext_new_extent_cb, &bp);
 455         ext3_ext_invalidate_cache(base);
 456
 457         return err;
 458 }
 459
 460 int fsfilt_ext3_map_ext_inode_pages(struct inode *inode, struct page **page,
 461                                     int pages, unsigned long *blocks,
 462                                     int create)
 463 {
 464         int blocks_per_page = CFS_PAGE_SIZE >> inode->i_blkbits;
 465         int rc = 0, i = 0;
 466         struct page *fp = NULL;
 467         int clen = 0;
 468
 469         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 470                 inode->i_ino, pages, (*page)->index);
 471
 472         /* pages are sorted already. so, we just have to find
 473          * contig. space and process them properly */
 474         while (i < pages) {
 475                 if (fp == NULL) {
 476                         /* start new extent */
 477                         fp = *page++;
 478                         clen = 1;
 479                         i++;
 480                         continue;
 481                 } else if (fp->index + clen == (*page)->index) {
 482                         /* continue the extent */
 483                         page++;
 484                         clen++;
 485                         i++;
 486                         continue;
 487                 }
 488
 489                 /* process found extent */
 490                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 491                                         clen * blocks_per_page, blocks,
 492                                         create);
 493                 if (rc)
 494                         GOTO(cleanup, rc);
 495
 496                 /* look for next extent */
 497                 fp = NULL;
 498                 blocks += blocks_per_page * clen;
 499         }
 500
 501         if (fp)
 502                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 503                                         clen * blocks_per_page, blocks,
 504                                         create);
 505 cleanup:
 506         return rc;
 507 }
 508
 509 int fsfilt_ext3_map_bm_inode_pages(struct inode *inode, struct page **page,
 510                                    int pages, unsigned long *blocks,
 511                                    int create)
 512 {
 513         int blocks_per_page = CFS_PAGE_SIZE >> inode->i_blkbits;
 514         unsigned long *b;
 515         int rc = 0, i;
 516
 517         for (i = 0, b = blocks; i < pages; i++, page++) {
 518                 rc = ext3_map_inode_page(inode, *page, b, create);
 519                 if (rc) {
 520                         CERROR("ino %lu, blk %lu create %d: rc %d\n",
 521                                inode->i_ino, *b, create, rc);
 522                         break;
 523                 }
 524
 525                 b += blocks_per_page;
 526         }
 527         return rc;
 528 }
 529
 530 int fsfilt_ext3_map_inode_pages(struct inode *inode, struct page **page,
 531                                 int pages, unsigned long *blocks,
 532                                 int create, struct mutex *optional_mutex)
 533 {
 534         int rc;
 535
 536         if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL) {
 537                 rc = fsfilt_ext3_map_ext_inode_pages(inode, page, pages,
 538                                                      blocks, create);
 539                 return rc;
 540         }
 541         if (optional_mutex != NULL)
 542                 mutex_lock(optional_mutex);
 543         rc = fsfilt_ext3_map_bm_inode_pages(inode, page, pages, blocks, create);
 544         if (optional_mutex != NULL)
 545                 mutex_unlock(optional_mutex);
 546
 547         return rc;
 548 }
 549
 550 int fsfilt_ext3_read(struct inode *inode, void *buf, int size, loff_t *offs)
 551 {
 552         unsigned long block;
 553         struct buffer_head *bh;
 554         int err, blocksize, csize, boffs, osize = size;
 555
 556         /* prevent reading after eof */
 557         spin_lock(&inode->i_lock);
 558         if (i_size_read(inode) < *offs + size) {
 559                 size = i_size_read(inode) - *offs;
 560                 spin_unlock(&inode->i_lock);
 561                 if (size < 0) {
 562                         CDEBUG(D_EXT2, "size %llu is too short for read @%llu\n",
 563                                i_size_read(inode), *offs);
 564                         return -EBADR;
 565                 } else if (size == 0) {
 566                         return 0;
 567                 }
 568         } else {
 569                 spin_unlock(&inode->i_lock);
 570         }
 571
 572         blocksize = 1 << inode->i_blkbits;
 573
 574         while (size > 0) {
 575                 block = *offs >> inode->i_blkbits;
 576                 boffs = *offs & (blocksize - 1);
 577                 csize = min(blocksize - boffs, size);
 578                 bh = ext3_bread(NULL, inode, block, 0, &err);
 579                 if (!bh) {
 580                         CERROR("can't read block: %d\n", err);
 581                         return err;
 582                 }
 583
 584                 memcpy(buf, bh->b_data + boffs, csize);
 585                 brelse(bh);
 586
 587                 *offs += csize;
 588                 buf += csize;
 589                 size -= csize;
 590         }
 591         return osize;
 592 }
 593 EXPORT_SYMBOL(fsfilt_ext3_read);
 594
 595 static int fsfilt_ext3_read_record(struct file * file, void *buf,
 596                                    int size, loff_t *offs)
 597 {
 598         int rc;
 599         rc = fsfilt_ext3_read(file->f_dentry->d_inode, buf, size, offs);
 600         if (rc > 0)
 601                 rc = 0;
 602         return rc;
 603 }
 604
 605 int fsfilt_ext3_write_handle(struct inode *inode, void *buf, int bufsize,
 606                                 loff_t *offs, handle_t *handle)
 607 {
 608         struct buffer_head *bh = NULL;
 609         loff_t old_size = i_size_read(inode), offset = *offs;
 610         loff_t new_size = i_size_read(inode);
 611         unsigned long block;
 612         int err = 0, blocksize = 1 << inode->i_blkbits, size, boffs;
 613
 614         while (bufsize > 0) {
 615                 if (bh != NULL)
 616                         brelse(bh);
 617
 618                 block = offset >> inode->i_blkbits;
 619                 boffs = offset & (blocksize - 1);
 620                 size = min(blocksize - boffs, bufsize);
 621                 bh = ext3_bread(handle, inode, block, 1, &err);
 622                 if (!bh) {
 623                         CERROR("can't read/create block: %d\n", err);
 624                         break;
 625                 }
 626
 627                 err = ext3_journal_get_write_access(handle, bh);
 628                 if (err) {
 629                         CERROR("journal_get_write_access() returned error %d\n",
 630                                err);
 631                         break;
 632                 }
 633                 LASSERT(bh->b_data + boffs + size <= bh->b_data + bh->b_size);
 634                 memcpy(bh->b_data + boffs, buf, size);
 635                 err = ext3_journal_dirty_metadata(handle, bh);
 636                 if (err) {
 637                         CERROR("journal_dirty_metadata() returned error %d\n",
 638                                err);
 639                         break;
 640                 }
 641                 if (offset + size > new_size)
 642                         new_size = offset + size;
 643                 offset += size;
 644                 bufsize -= size;
 645                 buf += size;
 646         }
 647         if (bh)
 648                 brelse(bh);
 649
 650         /* correct in-core and on-disk sizes */
 651         if (new_size > i_size_read(inode)) {
 652                 spin_lock(&inode->i_lock);
 653                 if (new_size > i_size_read(inode))
 654                         i_size_write(inode, new_size);
 655                 if (i_size_read(inode) > EXT3_I(inode)->i_disksize)
 656                         EXT3_I(inode)->i_disksize = i_size_read(inode);
 657                 if (i_size_read(inode) > old_size) {
 658                         spin_unlock(&inode->i_lock);
 659                         mark_inode_dirty(inode);
 660                 } else {
 661                         spin_unlock(&inode->i_lock);
 662                 }
 663         }
 664
 665         if (err == 0)
 666                 *offs = offset;
 667         return err;
 668 }
 669 EXPORT_SYMBOL(fsfilt_ext3_write_handle);
 670
 671 static int fsfilt_ext3_write_record(struct file *file, void *buf, int bufsize,
 672                                     loff_t *offs, int force_sync)
 673 {
 674         struct inode *inode = file->f_dentry->d_inode;
 675         handle_t *handle;
 676         int err, block_count = 0, blocksize;
 677
 678         /* Determine how many transaction credits are needed */
 679         blocksize = 1 << inode->i_blkbits;
 680         block_count = (*offs & (blocksize - 1)) + bufsize;
 681         block_count = (block_count + blocksize - 1) >> inode->i_blkbits;
 682
 683         handle = ext3_journal_start(inode,
 684                         block_count * EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + 2);
 685         if (IS_ERR(handle)) {
 686                 CERROR("can't start transaction for %d blocks (%d bytes)\n",
 687                        block_count * EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + 2,
 688                        bufsize);
 689                 return PTR_ERR(handle);
 690         }
 691
 692         err = fsfilt_ext3_write_handle(inode, buf, bufsize, offs, handle);
 693
 694         if (!err && force_sync)
 695                 handle->h_sync = 1; /* recovery likes this */
 696
 697         ext3_journal_stop(handle);
 698
 699         return err;
 700 }
 701
 702 static int fsfilt_ext3_setup(struct super_block *sb)
 703 {
 704         if (!EXT3_HAS_COMPAT_FEATURE(sb,
 705                                 EXT3_FEATURE_COMPAT_HAS_JOURNAL)) {
 706                 CERROR("ext3 mounted without journal\n");
 707                 return -EINVAL;
 708         }
 709
 710 #ifdef S_PDIROPS
 711         CWARN("Enabling PDIROPS\n");
 712         set_opt(EXT3_SB(sb)->s_mount_opt, PDIROPS);
 713         sb->s_flags |= S_PDIROPS;
 714 #endif
 715         if (!EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
 716                 CWARN("filesystem doesn't have dir_index feature enabled\n");
 717         return 0;
 718 }
 719 static struct fsfilt_operations fsfilt_ext3_ops = {
 720         .fs_type                = "ext3",
 721         .fs_owner               = THIS_MODULE,
 722         .fs_getlabel            = fsfilt_ext3_get_label,
 723         .fs_start               = fsfilt_ext3_start,
 724         .fs_commit              = fsfilt_ext3_commit,
 725         .fs_map_inode_pages     = fsfilt_ext3_map_inode_pages,
 726         .fs_write_record        = fsfilt_ext3_write_record,
 727         .fs_read_record         = fsfilt_ext3_read_record,
 728         .fs_setup               = fsfilt_ext3_setup,
 729 };
 730
 731 static int __init fsfilt_ext3_init(void)
 732 {
 733         int rc;
 734
 735         fcb_cache = cfs_mem_cache_create("fsfilt_ext3_fcb",
 736                                          sizeof(struct fsfilt_cb_data), 0, 0);
 737         if (!fcb_cache) {
 738                 CERROR("error allocating fsfilt journal callback cache\n");
 739                 GOTO(out, rc = -ENOMEM);
 740         }
 741
 742         rc = fsfilt_register_ops(&fsfilt_ext3_ops);
 743
 744         if (rc) {
 745                 int err = cfs_mem_cache_destroy(fcb_cache);
 746                 LASSERTF(err == 0, "error destroying new cache: rc %d\n", err);
 747         }
 748 out:
 749         return rc;
 750 }
 751
 752 static void __exit fsfilt_ext3_exit(void)
 753 {
 754         int rc;
 755
 756         fsfilt_unregister_ops(&fsfilt_ext3_ops);
 757         rc = cfs_mem_cache_destroy(fcb_cache);
 758         LASSERTF(rc == 0, "couldn't destroy fcb_cache slab\n");
 759 }
 760
 761 module_init(fsfilt_ext3_init);
 762 module_exit(fsfilt_ext3_exit);
 763
 764 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
 765 MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1");
 766 MODULE_LICENSE("GPL");