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/version.h>
  38 #include <linux/ext3_xattr.h>
  39
  40 #include <linux/kp30.h>
  41 #include <linux/lustre_fsfilt.h>
  42 #include <linux/obd.h>
  43 #include <linux/obd_class.h>
  44
  45 static kmem_cache_t *fcb_cache;
  46 static atomic_t fcb_cache_count = ATOMIC_INIT(0);
  47
  48 struct fsfilt_cb_data {
  49         struct journal_callback cb_jcb; /* jbd private data - MUST BE FIRST */
  50         fsfilt_cb_t cb_func;            /* MDS/OBD completion function */
  51         struct obd_device *cb_obd;      /* MDS/OBD completion device */
  52         __u64 cb_last_rcvd;             /* MDS/OST last committed operation */
  53         void *cb_data;                  /* MDS/OST completion function data */
  54 };
  55
  56 #ifndef EXT3_XATTR_INDEX_TRUSTED        /* temporary until we hit l28 kernel */
  57 #define EXT3_XATTR_INDEX_TRUSTED        4
  58 #endif
  59 #define XATTR_LUSTRE_MDS_LOV_EA         "lov"
  60
  61 /*
  62  * We don't currently need any additional blocks for rmdir and
  63  * unlink transactions because we are storing the OST oa_id inside
  64  * the inode (which we will be changing anyways as part of this
  65  * transaction).
  66  */
  67 static void *fsfilt_ext3_start(struct inode *inode, int op, void *desc_private,
  68                                int logs)
  69 {
  70         /* For updates to the last recieved file */
  71         int nblocks = EXT3_SINGLEDATA_TRANS_BLOCKS;
  72         journal_t *journal;
  73         void *handle;
  74
  75         if (current->journal_info) {
  76                 CDEBUG(D_INODE, "increasing refcount on %p\n",
  77                        current->journal_info);
  78                 goto journal_start;
  79         }
  80
  81         switch(op) {
  82         case FSFILT_OP_RMDIR:
  83         case FSFILT_OP_UNLINK:
  84                 /* delete one file + create/update logs for each stripe */
  85                 nblocks += EXT3_DELETE_TRANS_BLOCKS;
  86                 nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
  87                             EXT3_SINGLEDATA_TRANS_BLOCKS) * logs;
  88                 break;
  89         case FSFILT_OP_RENAME:
  90                 /* modify additional directory */
  91                 nblocks += EXT3_SINGLEDATA_TRANS_BLOCKS;
  92                 /* no break */
  93         case FSFILT_OP_SYMLINK:
  94                 /* additional block + block bitmap + GDT for long symlink */
  95                 nblocks += 3;
  96                 /* no break */
  97         case FSFILT_OP_CREATE:
  98                 /* create/update logs for each stripe */
  99                 nblocks += (EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 100                             EXT3_SINGLEDATA_TRANS_BLOCKS) * logs;
 101                 /* no break */
 102         case FSFILT_OP_MKDIR:
 103         case FSFILT_OP_MKNOD:
 104                 /* modify one inode + block bitmap + GDT */
 105                 nblocks += 3;
 106                 /* no break */
 107         case FSFILT_OP_LINK:
 108                 /* modify parent directory */
 109                 nblocks += EXT3_INDEX_EXTRA_TRANS_BLOCKS +
 110                         EXT3_DATA_TRANS_BLOCKS;
 111                 break;
 112         case FSFILT_OP_SETATTR:
 113                 /* Setattr on inode */
 114                 nblocks += 1;
 115                 break;
 116         case FSFILT_OP_CANCEL_UNLINK:
 117                 /* blocks for log header bitmap update OR
 118                  * blocks for catalog header bitmap update + unlink of logs */
 119                 nblocks = (LLOG_CHUNK_SIZE >> inode->i_blkbits) +
 120                         EXT3_DELETE_TRANS_BLOCKS * logs;
 121                 break;
 122         default: CERROR("unknown transaction start op %d\n", op);
 123                  LBUG();
 124         }
 125
 126         LASSERT(current->journal_info == desc_private);
 127         journal = EXT3_SB(inode->i_sb)->s_journal;
 128         if (nblocks > journal->j_max_transaction_buffers) {
 129                 CERROR("too many credits %d for op %ux%u using %d instead\n",
 130                        nblocks, op, logs, journal->j_max_transaction_buffers);
 131                 nblocks = journal->j_max_transaction_buffers;
 132         }
 133
 134  journal_start:
 135         lock_kernel();
 136         handle = journal_start(EXT3_JOURNAL(inode), nblocks);
 137         unlock_kernel();
 138
 139         if (!IS_ERR(handle))
 140                 LASSERT(current->journal_info == handle);
 141         else
 142                 CERROR("error starting handle for op %u (%u credits): rc %ld\n",
 143                        op, nblocks, PTR_ERR(handle));
 144         return handle;
 145 }
 146
 147 /*
 148  * Calculate the number of buffer credits needed to write multiple pages in
 149  * a single ext3 transaction.  No, this shouldn't be here, but as yet ext3
 150  * doesn't have a nice API for calculating this sort of thing in advance.
 151  *
 152  * See comment above ext3_writepage_trans_blocks for details.  We assume
 153  * no data journaling is being done, but it does allow for all of the pages
 154  * being non-contiguous.  If we are guaranteed contiguous pages we could
 155  * reduce the number of (d)indirect blocks a lot.
 156  *
 157  * With N blocks per page and P pages, for each inode we have at most:
 158  * N*P indirect
 159  * min(N*P, blocksize/4 + 1) dindirect blocks
 160  * niocount tindirect
 161  *
 162  * For the entire filesystem, we have at most:
 163  * min(sum(nindir + P), ngroups) bitmap blocks (from the above)
 164  * min(sum(nindir + P), gdblocks) group descriptor blocks (from the above)
 165  * objcount inode blocks
 166  * 1 superblock
 167  * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quota files
 168  *
 169  * 1 EXT3_DATA_TRANS_BLOCKS for the last_rcvd update.
 170  */
 171 static int fsfilt_ext3_credits_needed(int objcount, struct fsfilt_objinfo *fso,
 172                                       int niocount, struct niobuf_local *nb)
 173 {
 174         struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
 175         __u64 next_indir;
 176         const int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
 177         int nbitmaps = 0, ngdblocks;
 178         int needed = objcount + 1; /* inodes + superblock */
 179         int i, j;
 180
 181         for (i = 0, j = 0; i < objcount; i++, fso++) {
 182                 /* two or more dindirect blocks in case we cross boundary */
 183                 int ndind = (long)((nb[j + fso->fso_bufcnt - 1].offset -
 184                                     nb[j].offset) >>
 185                                    sb->s_blocksize_bits) /
 186                         (EXT3_ADDR_PER_BLOCK(sb) * EXT3_ADDR_PER_BLOCK(sb));
 187                 nbitmaps += min(fso->fso_bufcnt, ndind > 0 ? ndind : 2);
 188
 189                 /* leaf, indirect, tindirect blocks for first block */
 190                 nbitmaps += blockpp + 2;
 191
 192                 j += fso->fso_bufcnt;
 193         }
 194
 195         next_indir = nb[0].offset +
 196                 (EXT3_ADDR_PER_BLOCK(sb) << sb->s_blocksize_bits);
 197         for (i = 1; i < niocount; i++) {
 198                 if (nb[i].offset >= next_indir) {
 199                         nbitmaps++;     /* additional indirect */
 200                         next_indir = nb[i].offset +
 201                                 (EXT3_ADDR_PER_BLOCK(sb)<<sb->s_blocksize_bits);
 202                 } else if (nb[i].offset != nb[i - 1].offset + sb->s_blocksize) {
 203                         nbitmaps++;     /* additional indirect */
 204                 }
 205                 nbitmaps += blockpp;    /* each leaf in different group? */
 206         }
 207
 208         ngdblocks = nbitmaps;
 209         if (nbitmaps > EXT3_SB(sb)->s_groups_count)
 210                 nbitmaps = EXT3_SB(sb)->s_groups_count;
 211         if (ngdblocks > EXT3_SB(sb)->s_gdb_count)
 212                 ngdblocks = EXT3_SB(sb)->s_gdb_count;
 213
 214         needed += nbitmaps + ngdblocks;
 215
 216         /* last_rcvd update */
 217         needed += EXT3_DATA_TRANS_BLOCKS;
 218
 219 #if defined(CONFIG_QUOTA) && !defined(__x86_64__) /* XXX */
 220         /* We assume that there will be 1 bit set in s_dquot.flags for each
 221          * quota file that is active.  This is at least true for now.
 222          */
 223         needed += hweight32(sb_any_quota_enabled(sb)) *
 224                 EXT3_SINGLEDATA_TRANS_BLOCKS;
 225 #endif
 226
 227         return needed;
 228 }
 229
 230 /* We have to start a huge journal transaction here to hold all of the
 231  * metadata for the pages being written here.  This is necessitated by
 232  * the fact that we do lots of prepare_write operations before we do
 233  * any of the matching commit_write operations, so even if we split
 234  * up to use "smaller" transactions none of them could complete until
 235  * all of them were opened.  By having a single journal transaction,
 236  * we eliminate duplicate reservations for common blocks like the
 237  * superblock and group descriptors or bitmaps.
 238  *
 239  * We will start the transaction here, but each prepare_write will
 240  * add a refcount to the transaction, and each commit_write will
 241  * remove a refcount.  The transaction will be closed when all of
 242  * the pages have been written.
 243  */
 244 static void *fsfilt_ext3_brw_start(int objcount, struct fsfilt_objinfo *fso,
 245                                    int niocount, struct niobuf_local *nb,
 246                                    void *desc_private, int logs)
 247 {
 248         journal_t *journal;
 249         handle_t *handle;
 250         int needed;
 251         ENTRY;
 252
 253         LASSERT(current->journal_info == desc_private);
 254         journal = EXT3_SB(fso->fso_dentry->d_inode->i_sb)->s_journal;
 255         needed = fsfilt_ext3_credits_needed(objcount, fso, niocount, nb);
 256
 257         /* The number of blocks we could _possibly_ dirty can very large.
 258          * We reduce our request if it is absurd (and we couldn't get that
 259          * many credits for a single handle anyways).
 260          *
 261          * At some point we have to limit the size of I/Os sent at one time,
 262          * increase the size of the journal, or we have to calculate the
 263          * actual journal requirements more carefully by checking all of
 264          * the blocks instead of being maximally pessimistic.  It remains to
 265          * be seen if this is a real problem or not.
 266          */
 267         if (needed > journal->j_max_transaction_buffers) {
 268                 CERROR("want too many journal credits (%d) using %d instead\n",
 269                        needed, journal->j_max_transaction_buffers);
 270                 needed = journal->j_max_transaction_buffers;
 271         }
 272
 273         lock_kernel();
 274         handle = journal_start(journal, needed);
 275         unlock_kernel();
 276         if (IS_ERR(handle)) {
 277                 CERROR("can't get handle for %d credits: rc = %ld\n", needed,
 278                        PTR_ERR(handle));
 279         } else {
 280                 LASSERT(handle->h_buffer_credits >= needed);
 281                 LASSERT(current->journal_info == handle);
 282         }
 283
 284         RETURN(handle);
 285 }
 286
 287 static int fsfilt_ext3_commit(struct inode *inode, void *h, int force_sync)
 288 {
 289         int rc;
 290         handle_t *handle = h;
 291
 292         LASSERT(current->journal_info == handle);
 293         if (force_sync)
 294                 handle->h_sync = 1; /* recovery likes this */
 295
 296         lock_kernel();
 297         rc = journal_stop(handle);
 298         unlock_kernel();
 299
 300         // LASSERT(current->journal_info == NULL);
 301         return rc;
 302 }
 303
 304 static int fsfilt_ext3_commit_async(struct inode *inode, void *h,
 305                                         void **wait_handle)
 306 {
 307         unsigned long tid;
 308         transaction_t *transaction;
 309 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 310         unsigned long rtid;
 311 #endif
 312         handle_t *handle = h;
 313         journal_t *journal;
 314         int rc;
 315
 316         LASSERT(current->journal_info == handle);
 317
 318         lock_kernel();
 319         transaction = handle->h_transaction;
 320         journal = transaction->t_journal;
 321         tid = transaction->t_tid;
 322         /* we don't want to be blocked */
 323         handle->h_sync = 0;
 324         rc = journal_stop(handle);
 325         if (rc) {
 326                 CERROR("error while stopping transaction: %d\n", rc);
 327                 unlock_kernel();
 328                 return rc;
 329         }
 330 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
 331         rtid = log_start_commit(journal, transaction);
 332         if (rtid != tid)
 333                 CERROR("strange race: %lu != %lu\n",
 334                        (unsigned long) tid, (unsigned long) rtid);
 335 #else
 336         log_start_commit(journal, transaction->t_tid);
 337 #endif
 338         unlock_kernel();
 339
 340         *wait_handle = (void *) tid;
 341         CDEBUG(D_INODE, "commit async: %lu\n", (unsigned long) tid);
 342         return 0;
 343 }
 344
 345 static int fsfilt_ext3_commit_wait(struct inode *inode, void *h)
 346 {
 347         tid_t tid = (tid_t)(long)h;
 348
 349         CDEBUG(D_INODE, "commit wait: %lu\n", (unsigned long) tid);
 350         if (is_journal_aborted(EXT3_JOURNAL(inode)))
 351                 return -EIO;
 352
 353         log_wait_commit(EXT3_JOURNAL(inode), tid);
 354
 355         return 0;
 356 }
 357
 358 static int fsfilt_ext3_setattr(struct dentry *dentry, void *handle,
 359                                struct iattr *iattr, int do_trunc)
 360 {
 361         struct inode *inode = dentry->d_inode;
 362         int rc;
 363
 364         lock_kernel();
 365
 366         /* A _really_ horrible hack to avoid removing the data stored
 367          * in the block pointers; this is really the "small" stripe MD data.
 368          * We can avoid further hackery by virtue of the MDS file size being
 369          * zero all the time (which doesn't invoke block truncate at unlink
 370          * time), so we assert we never change the MDS file size from zero. */
 371         if (iattr->ia_valid & ATTR_SIZE && !do_trunc) {
 372                 /* ATTR_SIZE would invoke truncate: clear it */
 373                 iattr->ia_valid &= ~ATTR_SIZE;
 374                 EXT3_I(inode)->i_disksize = inode->i_size = iattr->ia_size;
 375
 376                 /* make sure _something_ gets set - so new inode
 377                  * goes to disk (probably won't work over XFS */
 378                 if (!(iattr->ia_valid & (ATTR_MODE | ATTR_MTIME | ATTR_CTIME))){
 379                         iattr->ia_valid |= ATTR_MODE;
 380                         iattr->ia_mode = inode->i_mode;
 381                 }
 382         }
 383
 384         /* Don't allow setattr to change file type */
 385         iattr->ia_mode = (inode->i_mode & S_IFMT)|(iattr->ia_mode & ~S_IFMT);
 386
 387         /* We set these flags on the client, but have already checked perms
 388          * so don't confuse inode_change_ok. */
 389         iattr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET);
 390
 391         if (inode->i_op->setattr) {
 392                 rc = inode->i_op->setattr(dentry, iattr);
 393         } else {
 394                 rc = inode_change_ok(inode, iattr);
 395                 if (!rc)
 396                         rc = inode_setattr(inode, iattr);
 397         }
 398
 399         unlock_kernel();
 400
 401         return rc;
 402 }
 403
 404 static int fsfilt_ext3_iocontrol(struct inode * inode, struct file *file,
 405                                  unsigned int cmd, unsigned long arg)
 406 {
 407         int rc = 0;
 408         ENTRY;
 409
 410         if (inode->i_fop->ioctl)
 411                 rc = inode->i_fop->ioctl(inode, file, cmd, arg);
 412         else
 413                 RETURN(-ENOTTY);
 414
 415         RETURN(rc);
 416 }
 417
 418 static int fsfilt_ext3_set_md(struct inode *inode, void *handle,
 419                               void *lmm, int lmm_size)
 420 {
 421         int rc;
 422
 423         /* keep this when we get rid of OLD_EA (too noisy during conversion) */
 424         if (EXT3_I(inode)->i_file_acl /* || large inode EA flag */)
 425                 CWARN("setting EA on %lu/%u again... interesting\n",
 426                        inode->i_ino, inode->i_generation);
 427
 428         lock_kernel();
 429         rc = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_TRUSTED,
 430                                    XATTR_LUSTRE_MDS_LOV_EA, lmm, lmm_size, 0);
 431
 432         unlock_kernel();
 433
 434         if (rc)
 435                 CERROR("error adding MD data to inode %lu: rc = %d\n",
 436                        inode->i_ino, rc);
 437         return rc;
 438 }
 439
 440 /* Must be called with i_sem held */
 441 static int fsfilt_ext3_get_md(struct inode *inode, void *lmm, int lmm_size)
 442 {
 443         int rc;
 444
 445         LASSERT(down_trylock(&inode->i_sem) != 0);
 446         lock_kernel();
 447
 448         rc = ext3_xattr_get(inode, EXT3_XATTR_INDEX_TRUSTED,
 449                             XATTR_LUSTRE_MDS_LOV_EA, lmm, lmm_size);
 450         unlock_kernel();
 451
 452         /* This gives us the MD size */
 453         if (lmm == NULL)
 454                 return (rc == -ENODATA) ? 0 : rc;
 455
 456         if (rc < 0) {
 457                 CDEBUG(D_INFO, "error getting EA %d/%s from inode %lu: rc %d\n",
 458                        EXT3_XATTR_INDEX_TRUSTED, XATTR_LUSTRE_MDS_LOV_EA,
 459                        inode->i_ino, rc);
 460                 memset(lmm, 0, lmm_size);
 461                 return (rc == -ENODATA) ? 0 : rc;
 462         }
 463
 464         return rc;
 465 }
 466
 467 static ssize_t fsfilt_ext3_readpage(struct file *file, char *buf, size_t count,
 468                                     loff_t *off)
 469 {
 470         struct inode *inode = file->f_dentry->d_inode;
 471         int rc = 0;
 472
 473         if (S_ISREG(inode->i_mode))
 474                 rc = file->f_op->read(file, buf, count, off);
 475         else {
 476                 const int blkbits = inode->i_sb->s_blocksize_bits;
 477                 const int blksize = inode->i_sb->s_blocksize;
 478
 479                 CDEBUG(D_EXT2, "reading "LPSZ" at dir %lu+%llu\n",
 480                        count, inode->i_ino, *off);
 481                 while (count > 0) {
 482                         struct buffer_head *bh;
 483
 484                         bh = NULL;
 485                         if (*off < inode->i_size) {
 486                                 int err = 0;
 487
 488                                 bh = ext3_bread(NULL, inode, *off >> blkbits,
 489                                                 0, &err);
 490
 491                                 CDEBUG(D_EXT2, "read %u@%llu\n", blksize, *off);
 492
 493                                 if (bh) {
 494                                         memcpy(buf, bh->b_data, blksize);
 495                                         brelse(bh);
 496                                 } else if (err) {
 497                                         /* XXX in theory we should just fake
 498                                          * this buffer and continue like ext3,
 499                                          * especially if this is a partial read
 500                                          */
 501                                         CERROR("error read dir %lu+%llu: %d\n",
 502                                                inode->i_ino, *off, err);
 503                                         RETURN(err);
 504                                 }
 505                         }
 506                         if (!bh) {
 507                                 struct ext3_dir_entry_2 *fake = (void *)buf;
 508
 509                                 CDEBUG(D_EXT2, "fake %u@%llu\n", blksize, *off);
 510                                 memset(fake, 0, sizeof(*fake));
 511                                 fake->rec_len = cpu_to_le32(blksize);
 512                         }
 513                         count -= blksize;
 514                         buf += blksize;
 515                         *off += blksize;
 516                         rc += blksize;
 517                 }
 518         }
 519
 520         return rc;
 521 }
 522
 523 static void fsfilt_ext3_cb_func(struct journal_callback *jcb, int error)
 524 {
 525         struct fsfilt_cb_data *fcb = (struct fsfilt_cb_data *)jcb;
 526
 527         fcb->cb_func(fcb->cb_obd, fcb->cb_last_rcvd, fcb->cb_data, error);
 528
 529         OBD_SLAB_FREE(fcb, fcb_cache, sizeof *fcb);
 530         atomic_dec(&fcb_cache_count);
 531 }
 532
 533 static int fsfilt_ext3_add_journal_cb(struct obd_device *obd, __u64 last_rcvd,
 534                                       void *handle, fsfilt_cb_t cb_func,
 535                                       void *cb_data)
 536 {
 537         struct fsfilt_cb_data *fcb;
 538
 539         OBD_SLAB_ALLOC(fcb, fcb_cache, GFP_NOFS, sizeof *fcb);
 540         if (fcb == NULL)
 541                 RETURN(-ENOMEM);
 542
 543         atomic_inc(&fcb_cache_count);
 544         fcb->cb_func = cb_func;
 545         fcb->cb_obd = obd;
 546         fcb->cb_last_rcvd = last_rcvd;
 547         fcb->cb_data = cb_data;
 548
 549         CDEBUG(D_EXT2, "set callback for last_rcvd: "LPD64"\n", last_rcvd);
 550         lock_kernel();
 551         journal_callback_set(handle, fsfilt_ext3_cb_func,
 552                              (struct journal_callback *)fcb);
 553         unlock_kernel();
 554
 555         return 0;
 556 }
 557
 558 /*
 559  * We need to hack the return value for the free inode counts because
 560  * the current EA code requires one filesystem block per inode with EAs,
 561  * so it is possible to run out of blocks before we run out of inodes.
 562  *
 563  * This can be removed when the ext3 EA code is fixed.
 564  */
 565 static int fsfilt_ext3_statfs(struct super_block *sb, struct obd_statfs *osfs)
 566 {
 567         struct kstatfs sfs;
 568         int rc;
 569
 570         memset(&sfs, 0, sizeof(sfs));
 571
 572         rc = sb->s_op->statfs(sb, &sfs);
 573
 574         if (!rc && sfs.f_bfree < sfs.f_ffree) {
 575                 sfs.f_files = (sfs.f_files - sfs.f_ffree) + sfs.f_bfree;
 576                 sfs.f_ffree = sfs.f_bfree;
 577         }
 578
 579         statfs_pack(osfs, &sfs);
 580         return rc;
 581 }
 582
 583 static int fsfilt_ext3_sync(struct super_block *sb)
 584 {
 585         return ext3_force_commit(sb);
 586 }
 587
 588 extern int ext3_map_inode_page(struct inode *inode, struct page *page,
 589                                unsigned long *blocks, int *created, int create);
 590 int fsfilt_ext3_map_inode_page(struct inode *inode, struct page *page,
 591                                unsigned long *blocks, int *created, int create)
 592 {
 593         return ext3_map_inode_page(inode, page, blocks, created, create);
 594 }
 595
 596 extern int ext3_prep_san_write(struct inode *inode, long *blocks,
 597                                int nblocks, loff_t newsize);
 598 static int fsfilt_ext3_prep_san_write(struct inode *inode, long *blocks,
 599                                       int nblocks, loff_t newsize)
 600 {
 601         return ext3_prep_san_write(inode, blocks, nblocks, newsize);
 602 }
 603
 604 static int fsfilt_ext3_read_record(struct file * file, void *buf,
 605                                    int size, loff_t *offs)
 606 {
 607         struct inode *inode = file->f_dentry->d_inode;
 608         unsigned long block;
 609         struct buffer_head *bh;
 610         int err, blocksize, csize, boffs;
 611
 612         /* prevent reading after eof */
 613         lock_kernel();
 614         if (inode->i_size < *offs + size) {
 615                 size = inode->i_size - *offs;
 616                 unlock_kernel();
 617                 if (size < 0) {
 618                         CERROR("size %llu is too short for read %u@%llu\n",
 619                                inode->i_size, size, *offs);
 620                         return -EIO;
 621                 } else if (size == 0) {
 622                         return 0;
 623                 }
 624         } else {
 625                 unlock_kernel();
 626         }
 627
 628         blocksize = 1 << inode->i_blkbits;
 629
 630         while (size > 0) {
 631                 block = *offs >> inode->i_blkbits;
 632                 boffs = *offs & (blocksize - 1);
 633                 csize = min(blocksize - boffs, size);
 634                 bh = ext3_bread(NULL, inode, block, 0, &err);
 635                 if (!bh) {
 636                         CERROR("can't read block: %d\n", err);
 637                         return err;
 638                 }
 639
 640                 memcpy(buf, bh->b_data + boffs, csize);
 641                 brelse(bh);
 642
 643                 *offs += csize;
 644                 buf += csize;
 645                 size -= csize;
 646         }
 647         return 0;
 648 }
 649
 650 static int fsfilt_ext3_write_record(struct file *file, void *buf, int bufsize,
 651                                     loff_t *offs, int force_sync)
 652 {
 653         struct buffer_head *bh = NULL;
 654         unsigned long block;
 655         struct inode *inode = file->f_dentry->d_inode;
 656         loff_t old_size = inode->i_size, offset = *offs;
 657         loff_t new_size = inode->i_size;
 658         journal_t *journal;
 659         handle_t *handle;
 660         int err, block_count = 0, blocksize, size, boffs;
 661
 662         /* Determine how many transaction credits are needed */
 663         blocksize = 1 << inode->i_blkbits;
 664         block_count = (*offs & (blocksize - 1)) + bufsize;
 665         block_count = (block_count + blocksize - 1) >> inode->i_blkbits;
 666
 667         journal = EXT3_SB(inode->i_sb)->s_journal;
 668         lock_kernel();
 669         handle = journal_start(journal,
 670                                block_count * EXT3_DATA_TRANS_BLOCKS + 2);
 671         unlock_kernel();
 672         if (IS_ERR(handle)) {
 673                 CERROR("can't start transaction\n");
 674                 return PTR_ERR(handle);
 675         }
 676
 677         while (bufsize > 0) {
 678                 if (bh != NULL)
 679                         brelse(bh);
 680
 681                 block = offset >> inode->i_blkbits;
 682                 boffs = offset & (blocksize - 1);
 683                 size = min(blocksize - boffs, bufsize);
 684                 bh = ext3_bread(handle, inode, block, 1, &err);
 685                 if (!bh) {
 686                         CERROR("can't read/create block: %d\n", err);
 687                         goto out;
 688                 }
 689
 690                 err = ext3_journal_get_write_access(handle, bh);
 691                 if (err) {
 692                         CERROR("journal_get_write_access() returned error %d\n",
 693                                err);
 694                         goto out;
 695                 }
 696                 LASSERT(bh->b_data + boffs + size <= bh->b_data + bh->b_size);
 697                 memcpy(bh->b_data + boffs, buf, size);
 698                 err = ext3_journal_dirty_metadata(handle, bh);
 699                 if (err) {
 700                         CERROR("journal_dirty_metadata() returned error %d\n",
 701                                err);
 702                         goto out;
 703                 }
 704                 if (offset + size > new_size)
 705                         new_size = offset + size;
 706                 offset += size;
 707                 bufsize -= size;
 708                 buf += size;
 709         }
 710
 711         if (force_sync)
 712                 handle->h_sync = 1; /* recovery likes this */
 713 out:
 714         if (bh)
 715                 brelse(bh);
 716
 717         /* correct in-core and on-disk sizes */
 718         if (new_size > inode->i_size) {
 719                 lock_kernel();
 720                 if (new_size > inode->i_size)
 721                         inode->i_size = new_size;
 722                 if (inode->i_size > EXT3_I(inode)->i_disksize)
 723                         EXT3_I(inode)->i_disksize = inode->i_size;
 724                 if (inode->i_size > old_size)
 725                         mark_inode_dirty(inode);
 726                 unlock_kernel();
 727         }
 728
 729         lock_kernel();
 730         journal_stop(handle);
 731         unlock_kernel();
 732
 733         if (err == 0)
 734                 *offs = offset;
 735         return err;
 736 }
 737
 738 static int fsfilt_ext3_setup(struct super_block *sb)
 739 {
 740 #if 0
 741         EXT3_SB(sb)->dx_lock = fsfilt_ext3_dx_lock;
 742         EXT3_SB(sb)->dx_unlock = fsfilt_ext3_dx_unlock;
 743 #endif
 744 #ifdef S_PDIROPS
 745         CWARN("Enabling PDIROPS\n");
 746         set_opt(EXT3_SB(sb)->s_mount_opt, PDIROPS);
 747         sb->s_flags |= S_PDIROPS;
 748 #endif
 749         return 0;
 750 }
 751
 752 /* If fso is NULL, op is FSFILT operation, otherwise op is number of fso
 753    objects. Logs is number of logfiles to update */
 754 static int fsfilt_ext3_get_op_len(int op, struct fsfilt_objinfo *fso, int logs)
 755 {
 756         if ( !fso ) {
 757                 switch(op) {
 758                 case FSFILT_OP_CREATE:
 759                                  /* directory leaf, index & indirect & EA*/
 760                         return 4 + 3 * logs;
 761                 case FSFILT_OP_UNLINK:
 762                         return 3 * logs;
 763                 }
 764         } else {
 765                 int i;
 766                 int needed = 0;
 767                 struct super_block *sb = fso->fso_dentry->d_inode->i_sb;
 768                 int blockpp = 1 << (PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
 769                 int addrpp = EXT3_ADDR_PER_BLOCK(sb) * blockpp;
 770                 for (i = 0; i < op; i++, fso++) {
 771                         int nblocks = fso->fso_bufcnt * blockpp;
 772                         int ndindirect = min(nblocks, addrpp + 1);
 773                         int nindir = nblocks + ndindirect + 1;
 774
 775                         needed += nindir;
 776                 }
 777                 return needed + 3 * logs;
 778         }
 779
 780         return 0;
 781 }
 782
 783 static struct fsfilt_operations fsfilt_ext3_ops = {
 784         fs_type:                "ext3",
 785         fs_owner:               THIS_MODULE,
 786         fs_start:               fsfilt_ext3_start,
 787         fs_brw_start:           fsfilt_ext3_brw_start,
 788         fs_commit:              fsfilt_ext3_commit,
 789         fs_commit_async:        fsfilt_ext3_commit_async,
 790         fs_commit_wait:         fsfilt_ext3_commit_wait,
 791         fs_setattr:             fsfilt_ext3_setattr,
 792         fs_iocontrol:           fsfilt_ext3_iocontrol,
 793         fs_set_md:              fsfilt_ext3_set_md,
 794         fs_get_md:              fsfilt_ext3_get_md,
 795         fs_readpage:            fsfilt_ext3_readpage,
 796         fs_add_journal_cb:      fsfilt_ext3_add_journal_cb,
 797         fs_statfs:              fsfilt_ext3_statfs,
 798         fs_sync:                fsfilt_ext3_sync,
 799         fs_map_inode_page:      fsfilt_ext3_map_inode_page,
 800         fs_prep_san_write:      fsfilt_ext3_prep_san_write,
 801         fs_write_record:        fsfilt_ext3_write_record,
 802         fs_read_record:         fsfilt_ext3_read_record,
 803         fs_setup:               fsfilt_ext3_setup,
 804         fs_get_op_len:          fsfilt_ext3_get_op_len,
 805 };
 806
 807 static int __init fsfilt_ext3_init(void)
 808 {
 809         int rc;
 810
 811         //rc = ext3_xattr_register();
 812         fcb_cache = kmem_cache_create("fsfilt_ext3_fcb",
 813                                       sizeof(struct fsfilt_cb_data), 0,
 814                                       0, NULL, NULL);
 815         if (!fcb_cache) {
 816                 CERROR("error allocating fsfilt journal callback cache\n");
 817                 GOTO(out, rc = -ENOMEM);
 818         }
 819
 820         rc = fsfilt_register_ops(&fsfilt_ext3_ops);
 821
 822         if (rc)
 823                 kmem_cache_destroy(fcb_cache);
 824 out:
 825         return rc;
 826 }
 827
 828 static void __exit fsfilt_ext3_exit(void)
 829 {
 830         int rc;
 831
 832         fsfilt_unregister_ops(&fsfilt_ext3_ops);
 833         rc = kmem_cache_destroy(fcb_cache);
 834
 835         if (rc || atomic_read(&fcb_cache_count)) {
 836                 CERROR("can't free fsfilt callback cache: count %d, rc = %d\n",
 837                        atomic_read(&fcb_cache_count), rc);
 838         }
 839
 840         //rc = ext3_xattr_unregister();
 841 }
 842
 843 module_init(fsfilt_ext3_init);
 844 module_exit(fsfilt_ext3_exit);
 845
 846 MODULE_AUTHOR("Cluster File Systems, Inc. <info@clusterfs.com>");
 847 MODULE_DESCRIPTION("Lustre ext3 Filesystem Helper v0.1");
 848 MODULE_LICENSE("GPL");