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, 2013, 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 #ifdef HAVE_EXT_PBLOCK /* Name changed to ext4_ext_pblock for kernel 2.6.35 */
  64 #define ext3_ext_pblock(ex) ext_pblock((ex))
  65 #endif
  66
  67 /* for kernels 2.6.18 and later */
  68 #define FSFILT_SINGLEDATA_TRANS_BLOCKS(sb) EXT3_SINGLEDATA_TRANS_BLOCKS(sb)
  69
  70 #define fsfilt_ext3_ext_insert_extent(handle, inode, path, newext, flag) \
  71                ext3_ext_insert_extent(handle, inode, path, newext, flag)
  72
  73 #define ext3_mb_discard_inode_preallocations(inode) \
  74                  ext3_discard_preallocations(inode)
  75
  76 #define fsfilt_log_start_commit(journal, tid) jbd2_log_start_commit(journal, tid)
  77 #define fsfilt_log_wait_commit(journal, tid) jbd2_log_wait_commit(journal, tid)
  78
  79 static struct kmem_cache *fcb_cache;
  80
  81 struct fsfilt_cb_data {
  82         struct ext4_journal_cb_entry cb_jcb; /* private data - MUST BE FIRST */
  83         fsfilt_cb_t cb_func;            /* MDS/OBD completion function */
  84         struct obd_device *cb_obd;      /* MDS/OBD completion device */
  85         __u64 cb_last_rcvd;             /* MDS/OST last committed operation */
  86         void *cb_data;                  /* MDS/OST completion function data */
  87 };
  88
  89 static char *fsfilt_ext3_get_label(struct super_block *sb)
  90 {
  91         return EXT3_SB(sb)->s_es->s_volume_name;
  92 }
  93
  94 /* kernel has ext4_blocks_for_truncate since linux-3.1.1 */
  95 #ifdef HAVE_BLOCKS_FOR_TRUNCATE
  96 # include <ext4/truncate.h>
  97 #else
  98 static inline unsigned long ext4_blocks_for_truncate(struct inode *inode)
  99 {
 100         ext4_lblk_t needed;
 101
 102         needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
 103         if (needed < 2)
 104                 needed = 2;
 105         if (needed > EXT4_MAX_TRANS_DATA)
 106                 needed = EXT4_MAX_TRANS_DATA;
 107         return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
 108 }
 109 #endif
 110
 111 /*
 112  * We don't currently need any additional blocks for rmdir and
 113  * unlink transactions because we are storing the OST oa_id inside
 114  * the inode (which we will be changing anyways as part of this
 115  * transaction).
 116  */
 117 static void *fsfilt_ext3_start(struct inode *inode, int op, void *desc_private,
 118                                int logs)
 119 {
 120         /* For updates to the last received file */
 121         int nblocks = FSFILT_SINGLEDATA_TRANS_BLOCKS(inode->i_sb);
 122         journal_t *journal;
 123         void *handle;
 124
 125         if (current->journal_info) {
 126                 CDEBUG(D_INODE, "increasing refcount on %p\n",
 127                        current->journal_info);
 128                 goto journal_start;
 129         }
 130
 131         switch(op) {
 132         case FSFILT_OP_UNLINK:
 133                 /* delete one file + create/update logs for each stripe */
 134                 nblocks += EXT3_DELETE_TRANS_BLOCKS(inode->i_sb);
 135                 nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 136                             FSFILT_SINGLEDATA_TRANS_BLOCKS(inode->i_sb)) * logs;
 137                 break;
 138         case FSFILT_OP_CANCEL_UNLINK:
 139                 LASSERT(logs == 1);
 140
 141                 /* blocks for log header bitmap update OR
 142                  * blocks for catalog header bitmap update + unlink of logs +
 143                  * blocks for delete the inode (include blocks truncating). */
 144                 nblocks = (LLOG_CHUNK_SIZE >> inode->i_blkbits) +
 145                           EXT3_DELETE_TRANS_BLOCKS(inode->i_sb) +
 146                           ext4_blocks_for_truncate(inode) + 3;
 147                 break;
 148         default: CERROR("unknown transaction start op %d\n", op);
 149                 LBUG();
 150         }
 151
 152         LASSERT(current->journal_info == desc_private);
 153         journal = EXT3_SB(inode->i_sb)->s_journal;
 154         if (nblocks > journal->j_max_transaction_buffers) {
 155                 CWARN("too many credits %d for op %ux%u using %d instead\n",
 156                        nblocks, op, logs, journal->j_max_transaction_buffers);
 157                 nblocks = journal->j_max_transaction_buffers;
 158         }
 159
 160  journal_start:
 161         LASSERTF(nblocks > 0, "can't start %d credit transaction\n", nblocks);
 162         handle = ext3_journal_start(inode, nblocks);
 163
 164         if (!IS_ERR(handle))
 165                 LASSERT(current->journal_info == handle);
 166         else
 167                 CERROR("error starting handle for op %u (%u credits): rc %ld\n",
 168                        op, nblocks, PTR_ERR(handle));
 169         return handle;
 170 }
 171
 172 static int fsfilt_ext3_commit(struct inode *inode, void *h, int force_sync)
 173 {
 174         int rc;
 175         handle_t *handle = h;
 176
 177         LASSERT(current->journal_info == handle);
 178         if (force_sync)
 179                 handle->h_sync = 1; /* recovery likes this */
 180
 181         rc = ext3_journal_stop(handle);
 182
 183         return rc;
 184 }
 185
 186 #ifndef EXT3_EXTENTS_FL
 187 #define EXT3_EXTENTS_FL                 0x00080000 /* Inode uses extents */
 188 #endif
 189
 190 #ifndef EXT_ASSERT
 191 #define EXT_ASSERT(cond)  BUG_ON(!(cond))
 192 #endif
 193
 194 #define EXT_GENERATION(inode)           (EXT4_I(inode)->i_ext_generation)
 195 #define ext3_ext_base                   inode
 196 #define ext3_ext_base2inode(inode)      (inode)
 197 #define EXT_DEPTH(inode)                ext_depth(inode)
 198 #define fsfilt_ext3_ext_walk_space(inode, block, num, cb, cbdata) \
 199                         ext3_ext_walk_space(inode, block, num, cb, cbdata);
 200
 201 struct bpointers {
 202         unsigned long *blocks;
 203         unsigned long start;
 204         int num;
 205         int init_num;
 206         int create;
 207 };
 208
 209 static long ext3_ext_find_goal(struct inode *inode, struct ext3_ext_path *path,
 210                                unsigned long block, int *aflags)
 211 {
 212         struct ext3_inode_info *ei = EXT3_I(inode);
 213         unsigned long bg_start;
 214         unsigned long colour;
 215         int depth;
 216
 217         if (path) {
 218                 struct ext3_extent *ex;
 219                 depth = path->p_depth;
 220
 221                 /* try to predict block placement */
 222                 if ((ex = path[depth].p_ext))
 223                         return ext4_ext_pblock(ex) + (block - le32_to_cpu(ex->ee_block));
 224
 225                 /* it looks index is empty
 226                  * try to find starting from index itself */
 227                 if (path[depth].p_bh)
 228                         return path[depth].p_bh->b_blocknr;
 229         }
 230
 231         /* OK. use inode's group */
 232         bg_start = (ei->i_block_group * EXT3_BLOCKS_PER_GROUP(inode->i_sb)) +
 233                 le32_to_cpu(EXT3_SB(inode->i_sb)->s_es->s_first_data_block);
 234         colour = (current->pid % 16) *
 235                 (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 236         return bg_start + colour + block;
 237 }
 238
 239 #define ll_unmap_underlying_metadata(sb, blocknr) \
 240         unmap_underlying_metadata((sb)->s_bdev, blocknr)
 241
 242 #ifndef EXT3_MB_HINT_GROUP_ALLOC
 243 static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base,
 244                                 struct ext3_ext_path *path, unsigned long block,
 245                                 unsigned long *count, int *err)
 246 {
 247         unsigned long pblock, goal;
 248         int aflags = 0;
 249         struct inode *inode = ext3_ext_base2inode(base);
 250
 251         goal = ext3_ext_find_goal(inode, path, block, &aflags);
 252         aflags |= 2; /* block have been already reserved */
 253         pblock = ext3_mb_new_blocks(handle, inode, goal, count, aflags, err);
 254         return pblock;
 255
 256 }
 257 #else
 258 static unsigned long new_blocks(handle_t *handle, struct ext3_ext_base *base,
 259                                 struct ext3_ext_path *path, unsigned long block,
 260                                 unsigned long *count, int *err)
 261 {
 262         struct inode *inode = ext3_ext_base2inode(base);
 263         struct ext3_allocation_request ar;
 264         unsigned long pblock;
 265         int aflags;
 266
 267         /* find neighbour allocated blocks */
 268         ar.lleft = block;
 269         *err = ext3_ext_search_left(base, path, &ar.lleft, &ar.pleft);
 270         if (*err)
 271                 return 0;
 272         ar.lright = block;
 273         *err = ext3_ext_search_right(base, path, &ar.lright, &ar.pright);
 274         if (*err)
 275                 return 0;
 276
 277         /* allocate new block */
 278         ar.goal = ext3_ext_find_goal(inode, path, block, &aflags);
 279         ar.inode = inode;
 280         ar.logical = block;
 281         ar.len = *count;
 282         ar.flags = EXT3_MB_HINT_DATA;
 283         pblock = ext3_mb_new_blocks(handle, &ar, err);
 284         *count = ar.len;
 285         return pblock;
 286 }
 287 #endif
 288
 289 static int ext3_ext_new_extent_cb(struct ext3_ext_base *base,
 290                                   struct ext3_ext_path *path,
 291                                   struct ext3_ext_cache *cex,
 292 #ifdef HAVE_EXT_PREPARE_CB_EXTENT
 293                                    struct ext3_extent *ex,
 294 #endif
 295                                   void *cbdata)
 296 {
 297         struct bpointers *bp = cbdata;
 298         struct inode *inode = ext3_ext_base2inode(base);
 299         struct ext3_extent nex;
 300         unsigned long pblock;
 301         unsigned long tgen;
 302         int err, i;
 303         unsigned long count;
 304         handle_t *handle;
 305
 306 #ifdef EXT3_EXT_CACHE_EXTENT
 307         if (cex->ec_type == EXT3_EXT_CACHE_EXTENT)
 308 #else
 309         if ((cex->ec_len != 0) && (cex->ec_start != 0))
 310 #endif
 311                                                    {
 312                 err = EXT_CONTINUE;
 313                 goto map;
 314         }
 315
 316         if (bp->create == 0) {
 317                 i = 0;
 318                 if (cex->ec_block < bp->start)
 319                         i = bp->start - cex->ec_block;
 320                 if (i >= cex->ec_len)
 321                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 322                                         i, cex->ec_len);
 323                 for (; i < cex->ec_len && bp->num; i++) {
 324                         *(bp->blocks) = 0;
 325                         bp->blocks++;
 326                         bp->num--;
 327                         bp->start++;
 328                 }
 329
 330                 return EXT_CONTINUE;
 331         }
 332
 333         tgen = EXT_GENERATION(base);
 334         count = ext3_ext_calc_credits_for_insert(base, path);
 335
 336         handle = ext3_journal_start(inode, count+EXT3_ALLOC_NEEDED+1);
 337         if (IS_ERR(handle)) {
 338                 return PTR_ERR(handle);
 339         }
 340
 341         if (tgen != EXT_GENERATION(base)) {
 342                 /* the tree has changed. so path can be invalid at moment */
 343                 ext3_journal_stop(handle);
 344                 return EXT_REPEAT;
 345         }
 346
 347         /* In 2.6.32 kernel, ext4_ext_walk_space()'s callback func is not
 348          * protected by i_data_sem as whole. so we patch it to store
 349          * generation to path and now verify the tree hasn't changed */
 350         down_write((&EXT4_I(inode)->i_data_sem));
 351
 352         /* validate extent, make sure the extent tree does not changed */
 353         if (EXT_GENERATION(base) != path[0].p_generation) {
 354                 /* cex is invalid, try again */
 355                 up_write(&EXT4_I(inode)->i_data_sem);
 356                 ext3_journal_stop(handle);
 357                 return EXT_REPEAT;
 358         }
 359
 360         count = cex->ec_len;
 361         pblock = new_blocks(handle, base, path, cex->ec_block, &count, &err);
 362         if (!pblock)
 363                 goto out;
 364         EXT_ASSERT(count <= cex->ec_len);
 365
 366         /* insert new extent */
 367         nex.ee_block = cpu_to_le32(cex->ec_block);
 368         ext3_ext_store_pblock(&nex, pblock);
 369         nex.ee_len = cpu_to_le16(count);
 370         err = fsfilt_ext3_ext_insert_extent(handle, base, path, &nex, 0);
 371         if (err) {
 372                 /* free data blocks we just allocated */
 373                 /* not a good idea to call discard here directly,
 374                  * but otherwise we'd need to call it every free() */
 375 #ifdef EXT3_MB_HINT_GROUP_ALLOC
 376                 ext3_mb_discard_inode_preallocations(inode);
 377 #endif
 378 #ifdef HAVE_EXT_FREE_BLOCK_WITH_BUFFER_HEAD /* Introduced in 2.6.32-rc7 */
 379                 ext3_free_blocks(handle, inode, NULL, ext4_ext_pblock(&nex),
 380                                  cpu_to_le16(nex.ee_len), 0);
 381 #else
 382                 ext3_free_blocks(handle, inode, ext4_ext_pblock(&nex),
 383                                  cpu_to_le16(nex.ee_len), 0);
 384 #endif
 385                 goto out;
 386         }
 387
 388         /*
 389          * Putting len of the actual extent we just inserted,
 390          * we are asking ext3_ext_walk_space() to continue
 391          * scaning after that block
 392          */
 393         cex->ec_len = le16_to_cpu(nex.ee_len);
 394         cex->ec_start = ext4_ext_pblock(&nex);
 395         BUG_ON(le16_to_cpu(nex.ee_len) == 0);
 396         BUG_ON(le32_to_cpu(nex.ee_block) != cex->ec_block);
 397
 398 out:
 399         up_write((&EXT4_I(inode)->i_data_sem));
 400         ext3_journal_stop(handle);
 401 map:
 402         if (err >= 0) {
 403                 /* map blocks */
 404                 if (bp->num == 0) {
 405                         CERROR("hmm. why do we find this extent?\n");
 406                         CERROR("initial space: %lu:%u\n",
 407                                 bp->start, bp->init_num);
 408 #ifdef EXT3_EXT_CACHE_EXTENT
 409                         CERROR("current extent: %u/%u/%llu %d\n",
 410                                 cex->ec_block, cex->ec_len,
 411                                 (unsigned long long)cex->ec_start,
 412                                 cex->ec_type);
 413 #else
 414                         CERROR("current extent: %u/%u/%llu\n",
 415                                 cex->ec_block, cex->ec_len,
 416                                 (unsigned long long)cex->ec_start);
 417 #endif
 418                 }
 419                 i = 0;
 420                 if (cex->ec_block < bp->start)
 421                         i = bp->start - cex->ec_block;
 422                 if (i >= cex->ec_len)
 423                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 424                                         i, cex->ec_len);
 425                 for (; i < cex->ec_len && bp->num; i++) {
 426                         *(bp->blocks) = cex->ec_start + i;
 427 #ifdef EXT3_EXT_CACHE_EXTENT
 428                         if (cex->ec_type != EXT3_EXT_CACHE_EXTENT)
 429 #else
 430                         if ((cex->ec_len == 0) || (cex->ec_start == 0))
 431 #endif
 432                                                                         {
 433                                 /* unmap any possible underlying metadata from
 434                                  * the block device mapping.  bug 6998. */
 435                                 ll_unmap_underlying_metadata(inode->i_sb,
 436                                                              *(bp->blocks));
 437                         }
 438                         bp->blocks++;
 439                         bp->num--;
 440                         bp->start++;
 441                 }
 442         }
 443         return err;
 444 }
 445
 446 int fsfilt_map_nblocks(struct inode *inode, unsigned long block,
 447                        unsigned long num, unsigned long *blocks,
 448                        int create)
 449 {
 450         struct ext3_ext_base *base = inode;
 451         struct bpointers bp;
 452         int err;
 453
 454         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
 455                block, block + num - 1, (unsigned) inode->i_ino);
 456
 457         bp.blocks = blocks;
 458         bp.start = block;
 459         bp.init_num = bp.num = num;
 460         bp.create = create;
 461
 462         err = fsfilt_ext3_ext_walk_space(base, block, num,
 463                                          ext3_ext_new_extent_cb, &bp);
 464         ext3_ext_invalidate_cache(base);
 465
 466         return err;
 467 }
 468
 469 int fsfilt_ext3_map_ext_inode_pages(struct inode *inode, struct page **page,
 470                                     int pages, unsigned long *blocks,
 471                                     int create)
 472 {
 473         int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits;
 474         int rc = 0, i = 0;
 475         struct page *fp = NULL;
 476         int clen = 0;
 477
 478         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 479                 inode->i_ino, pages, (*page)->index);
 480
 481         /* pages are sorted already. so, we just have to find
 482          * contig. space and process them properly */
 483         while (i < pages) {
 484                 if (fp == NULL) {
 485                         /* start new extent */
 486                         fp = *page++;
 487                         clen = 1;
 488                         i++;
 489                         continue;
 490                 } else if (fp->index + clen == (*page)->index) {
 491                         /* continue the extent */
 492                         page++;
 493                         clen++;
 494                         i++;
 495                         continue;
 496                 }
 497
 498                 /* process found extent */
 499                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 500                                         clen * blocks_per_page, blocks,
 501                                         create);
 502                 if (rc)
 503                         GOTO(cleanup, rc);
 504
 505                 /* look for next extent */
 506                 fp = NULL;
 507                 blocks += blocks_per_page * clen;
 508         }
 509
 510         if (fp)
 511                 rc = fsfilt_map_nblocks(inode, fp->index * blocks_per_page,
 512                                         clen * blocks_per_page, blocks,
 513                                         create);
 514 cleanup:
 515         return rc;
 516 }
 517
 518 int fsfilt_ext3_map_bm_inode_pages(struct inode *inode, struct page **page,
 519                                    int pages, unsigned long *blocks,
 520                                    int create)
 521 {
 522         int blocks_per_page = PAGE_CACHE_SIZE >> inode->i_blkbits;
 523         unsigned long *b;
 524         int rc = 0, i;
 525
 526         for (i = 0, b = blocks; i < pages; i++, page++) {
 527                 rc = ext3_map_inode_page(inode, *page, b, create);
 528                 if (rc) {
 529                         CERROR("ino %lu, blk %lu create %d: rc %d\n",
 530                                inode->i_ino, *b, create, rc);
 531                         break;
 532                 }
 533
 534                 b += blocks_per_page;
 535         }
 536         return rc;
 537 }
 538
 539 int fsfilt_ext3_map_inode_pages(struct inode *inode, struct page **page,
 540                                 int pages, unsigned long *blocks,
 541                                 int create, struct mutex *optional_mutex)
 542 {
 543         int rc;
 544
 545         if (EXT3_I(inode)->i_flags & EXT3_EXTENTS_FL) {
 546                 rc = fsfilt_ext3_map_ext_inode_pages(inode, page, pages,
 547                                                      blocks, create);
 548                 return rc;
 549         }
 550         if (optional_mutex != NULL)
 551                 mutex_lock(optional_mutex);
 552         rc = fsfilt_ext3_map_bm_inode_pages(inode, page, pages, blocks, create);
 553         if (optional_mutex != NULL)
 554                 mutex_unlock(optional_mutex);
 555
 556         return rc;
 557 }
 558
 559 int fsfilt_ext3_read(struct inode *inode, void *buf, int size, loff_t *offs)
 560 {
 561         unsigned long block;
 562         struct buffer_head *bh;
 563         int err, blocksize, csize, boffs, osize = size;
 564
 565         /* prevent reading after eof */
 566         spin_lock(&inode->i_lock);
 567         if (i_size_read(inode) < *offs + size) {
 568                 size = i_size_read(inode) - *offs;
 569                 spin_unlock(&inode->i_lock);
 570                 if (size < 0) {
 571                         CDEBUG(D_EXT2, "size %llu is too short for read @%llu\n",
 572                                i_size_read(inode), *offs);
 573                         return -EBADR;
 574                 } else if (size == 0) {
 575                         return 0;
 576                 }
 577         } else {
 578                 spin_unlock(&inode->i_lock);
 579         }
 580
 581         blocksize = 1 << inode->i_blkbits;
 582
 583         while (size > 0) {
 584                 block = *offs >> inode->i_blkbits;
 585                 boffs = *offs & (blocksize - 1);
 586                 csize = min(blocksize - boffs, size);
 587                 bh = ext3_bread(NULL, inode, block, 0, &err);
 588                 if (!bh) {
 589                         CERROR("can't read block: %d\n", err);
 590                         return err;
 591                 }
 592
 593                 memcpy(buf, bh->b_data + boffs, csize);
 594                 brelse(bh);
 595
 596                 *offs += csize;
 597                 buf += csize;
 598                 size -= csize;
 599         }
 600         return osize;
 601 }
 602 EXPORT_SYMBOL(fsfilt_ext3_read);
 603
 604 static int fsfilt_ext3_read_record(struct file * file, void *buf,
 605                                    int size, loff_t *offs)
 606 {
 607         int rc;
 608         rc = fsfilt_ext3_read(file->f_dentry->d_inode, buf, size, offs);
 609         if (rc > 0)
 610                 rc = 0;
 611         return rc;
 612 }
 613
 614 int fsfilt_ext3_write_handle(struct inode *inode, void *buf, int bufsize,
 615                                 loff_t *offs, handle_t *handle)
 616 {
 617         struct buffer_head *bh = NULL;
 618         loff_t old_size = i_size_read(inode), offset = *offs;
 619         loff_t new_size = i_size_read(inode);
 620         unsigned long block;
 621         int err = 0, blocksize = 1 << inode->i_blkbits, size, boffs;
 622
 623         while (bufsize > 0) {
 624                 if (bh != NULL)
 625                         brelse(bh);
 626
 627                 block = offset >> inode->i_blkbits;
 628                 boffs = offset & (blocksize - 1);
 629                 size = min(blocksize - boffs, bufsize);
 630                 bh = ext3_bread(handle, inode, block, 1, &err);
 631                 if (!bh) {
 632                         CERROR("can't read/create block: %d\n", err);
 633                         break;
 634                 }
 635
 636                 err = ext3_journal_get_write_access(handle, bh);
 637                 if (err) {
 638                         CERROR("journal_get_write_access() returned error %d\n",
 639                                err);
 640                         break;
 641                 }
 642                 LASSERT(bh->b_data + boffs + size <= bh->b_data + bh->b_size);
 643                 memcpy(bh->b_data + boffs, buf, size);
 644                 err = ext3_journal_dirty_metadata(handle, bh);
 645                 if (err) {
 646                         CERROR("journal_dirty_metadata() returned error %d\n",
 647                                err);
 648                         break;
 649                 }
 650                 if (offset + size > new_size)
 651                         new_size = offset + size;
 652                 offset += size;
 653                 bufsize -= size;
 654                 buf += size;
 655         }
 656         if (bh)
 657                 brelse(bh);
 658
 659         /* correct in-core and on-disk sizes */
 660         if (new_size > i_size_read(inode)) {
 661                 spin_lock(&inode->i_lock);
 662                 if (new_size > i_size_read(inode))
 663                         i_size_write(inode, new_size);
 664                 if (i_size_read(inode) > EXT3_I(inode)->i_disksize)
 665                         EXT3_I(inode)->i_disksize = i_size_read(inode);
 666                 if (i_size_read(inode) > old_size) {
 667                         spin_unlock(&inode->i_lock);
 668                         mark_inode_dirty(inode);
 669                 } else {
 670                         spin_unlock(&inode->i_lock);
 671                 }
 672         }
 673
 674         if (err == 0)
 675                 *offs = offset;
 676         return err;
 677 }
 678 EXPORT_SYMBOL(fsfilt_ext3_write_handle);
 679
 680 static int fsfilt_ext3_write_record(struct file *file, void *buf, int bufsize,
 681                                     loff_t *offs, int force_sync)
 682 {
 683         struct inode *inode = file->f_dentry->d_inode;
 684         handle_t *handle;
 685         int err, block_count = 0, blocksize;
 686
 687         /* Determine how many transaction credits are needed */
 688         blocksize = 1 << inode->i_blkbits;
 689         block_count = (*offs & (blocksize - 1)) + bufsize;
 690         block_count = (block_count + blocksize - 1) >> inode->i_blkbits;
 691
 692         handle = ext3_journal_start(inode,
 693                         block_count * EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + 2);
 694         if (IS_ERR(handle)) {
 695                 CERROR("can't start transaction for %d blocks (%d bytes)\n",
 696                        block_count * EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + 2,
 697                        bufsize);
 698                 return PTR_ERR(handle);
 699         }
 700
 701         err = fsfilt_ext3_write_handle(inode, buf, bufsize, offs, handle);
 702
 703         if (!err && force_sync)
 704                 handle->h_sync = 1; /* recovery likes this */
 705
 706         ext3_journal_stop(handle);
 707
 708         return err;
 709 }
 710
 711 static int fsfilt_ext3_setup(struct super_block *sb)
 712 {
 713         if (!EXT3_HAS_COMPAT_FEATURE(sb,
 714                                 EXT3_FEATURE_COMPAT_HAS_JOURNAL)) {
 715                 CERROR("ext3 mounted without journal\n");
 716                 return -EINVAL;
 717         }
 718
 719 #ifdef S_PDIROPS
 720         CWARN("Enabling PDIROPS\n");
 721         set_opt(EXT3_SB(sb)->s_mount_opt, PDIROPS);
 722         sb->s_flags |= S_PDIROPS;
 723 #endif
 724         if (!EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
 725                 CWARN("filesystem doesn't have dir_index feature enabled\n");
 726         return 0;
 727 }
 728 static struct fsfilt_operations fsfilt_ext3_ops = {
 729         .fs_type                = "ext3",
 730         .fs_owner               = THIS_MODULE,
 731         .fs_getlabel            = fsfilt_ext3_get_label,
 732         .fs_start               = fsfilt_ext3_start,
 733         .fs_commit              = fsfilt_ext3_commit,
 734         .fs_map_inode_pages     = fsfilt_ext3_map_inode_pages,
 735         .fs_write_record        = fsfilt_ext3_write_record,
 736         .fs_read_record         = fsfilt_ext3_read_record,
 737         .fs_setup               = fsfilt_ext3_setup,
 738 };
 739
 740 static int __init fsfilt_ext3_init(void)
 741 {
 742         int rc;
 743
 744         fcb_cache = kmem_cache_create("fsfilt_ext3_fcb",
 745                                       sizeof(struct fsfilt_cb_data),
 746                                       0, 0, NULL);
 747         if (!fcb_cache) {
 748                 CERROR("error allocating fsfilt journal callback cache\n");
 749                 GOTO(out, rc = -ENOMEM);
 750         }
 751
 752         rc = fsfilt_register_ops(&fsfilt_ext3_ops);
 753
 754         if (rc)
 755                 kmem_cache_destroy(fcb_cache);
 756 out:
 757         return rc;
 758 }
 759
 760 static void __exit fsfilt_ext3_exit(void)
 761 {
 762         fsfilt_unregister_ops(&fsfilt_ext3_ops);
 763         kmem_cache_destroy(fcb_cache);
 764 }
 765
 766 module_init(fsfilt_ext3_init);
 767 module_exit(fsfilt_ext3_exit);
 768
 769 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");
 770 MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1");
 771 MODULE_LICENSE("GPL");