fs/nilfs2/super.c

   1 /*
   2  * super.c - NILFS module and super block management.
   3  *
   4  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   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 as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * Written by Ryusuke Konishi <ryusuke@osrg.net>
  21  */
  22 /*
  23  *  linux/fs/ext2/super.c
  24  *
  25  * Copyright (C) 1992, 1993, 1994, 1995
  26  * Remy Card (card@masi.ibp.fr)
  27  * Laboratoire MASI - Institut Blaise Pascal
  28  * Universite Pierre et Marie Curie (Paris VI)
  29  *
  30  *  from
  31  *
  32  *  linux/fs/minix/inode.c
  33  *
  34  *  Copyright (C) 1991, 1992  Linus Torvalds
  35  *
  36  *  Big-endian to little-endian byte-swapping/bitmaps by
  37  *        David S. Miller (davem@caip.rutgers.edu), 1995
  38  */
  39
  40 #include <linux/module.h>
  41 #include <linux/string.h>
  42 #include <linux/slab.h>
  43 #include <linux/init.h>
  44 #include <linux/blkdev.h>
  45 #include <linux/parser.h>
  46 #include <linux/random.h>
  47 #include <linux/crc32.h>
  48 #include <linux/vfs.h>
  49 #include <linux/writeback.h>
  50 #include <linux/kobject.h>
  51 #include <linux/seq_file.h>
  52 #include <linux/mount.h>
  53 #include "nilfs.h"
  54 #include "export.h"
  55 #include "mdt.h"
  56 #include "alloc.h"
  57 #include "btree.h"
  58 #include "btnode.h"
  59 #include "page.h"
  60 #include "cpfile.h"
  61 #include "ifile.h"
  62 #include "dat.h"
  63 #include "segment.h"
  64 #include "segbuf.h"
  65
  66 MODULE_AUTHOR("NTT Corp.");
  67 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
  68                    "(NILFS)");
  69 MODULE_LICENSE("GPL");
  70
  71 struct kmem_cache *nilfs_inode_cachep;
  72 struct kmem_cache *nilfs_transaction_cachep;
  73 struct kmem_cache *nilfs_segbuf_cachep;
  74 struct kmem_cache *nilfs_btree_path_cache;
  75
  76 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
  77
  78 static void nilfs_set_error(struct nilfs_sb_info *sbi)
  79 {
  80         struct the_nilfs *nilfs = sbi->s_nilfs;
  81         struct nilfs_super_block **sbp;
  82
  83         down_write(&nilfs->ns_sem);
  84         if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
  85                 nilfs->ns_mount_state |= NILFS_ERROR_FS;
  86                 sbp = nilfs_prepare_super(sbi, 0);
  87                 if (likely(sbp)) {
  88                         sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
  89                         if (sbp[1])
  90                                 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
  91                         nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
  92                 }
  93         }
  94         up_write(&nilfs->ns_sem);
  95 }
  96
  97 /**
  98  * nilfs_error() - report failure condition on a filesystem
  99  *
 100  * nilfs_error() sets an ERROR_FS flag on the superblock as well as
 101  * reporting an error message.  It should be called when NILFS detects
 102  * incoherences or defects of meta data on disk.  As for sustainable
 103  * errors such as a single-shot I/O error, nilfs_warning() or the printk()
 104  * function should be used instead.
 105  *
 106  * The segment constructor must not call this function because it can
 107  * kill itself.
 108  */
 109 void nilfs_error(struct super_block *sb, const char *function,
 110                  const char *fmt, ...)
 111 {
 112         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 113         va_list args;
 114
 115         va_start(args, fmt);
 116         printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
 117         vprintk(fmt, args);
 118         printk("\n");
 119         va_end(args);
 120
 121         if (!(sb->s_flags & MS_RDONLY)) {
 122                 nilfs_set_error(sbi);
 123
 124                 if (nilfs_test_opt(sbi, ERRORS_RO)) {
 125                         printk(KERN_CRIT "Remounting filesystem read-only\n");
 126                         sb->s_flags |= MS_RDONLY;
 127                 }
 128         }
 129
 130         if (nilfs_test_opt(sbi, ERRORS_PANIC))
 131                 panic("NILFS (device %s): panic forced after error\n",
 132                       sb->s_id);
 133 }
 134
 135 void nilfs_warning(struct super_block *sb, const char *function,
 136                    const char *fmt, ...)
 137 {
 138         va_list args;
 139
 140         va_start(args, fmt);
 141         printk(KERN_WARNING "NILFS warning (device %s): %s: ",
 142                sb->s_id, function);
 143         vprintk(fmt, args);
 144         printk("\n");
 145         va_end(args);
 146 }
 147
 148
 149 struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
 150 {
 151         struct nilfs_inode_info *ii;
 152
 153         ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
 154         if (!ii)
 155                 return NULL;
 156         ii->i_bh = NULL;
 157         ii->i_state = 0;
 158         ii->i_cno = 0;
 159         ii->vfs_inode.i_version = 1;
 160         nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
 161         return &ii->vfs_inode;
 162 }
 163
 164 struct inode *nilfs_alloc_inode(struct super_block *sb)
 165 {
 166         return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
 167 }
 168
 169 void nilfs_destroy_inode(struct inode *inode)
 170 {
 171         struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 172
 173         if (mdi) {
 174                 kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
 175                 kfree(mdi);
 176         }
 177         kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
 178 }
 179
 180 static int nilfs_sync_super(struct nilfs_sb_info *sbi, int flag)
 181 {
 182         struct the_nilfs *nilfs = sbi->s_nilfs;
 183         int err;
 184
 185  retry:
 186         set_buffer_dirty(nilfs->ns_sbh[0]);
 187
 188         if (nilfs_test_opt(sbi, BARRIER)) {
 189                 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
 190                                           WRITE_SYNC | WRITE_BARRIER);
 191                 if (err == -EOPNOTSUPP) {
 192                         nilfs_warning(sbi->s_super, __func__,
 193                                       "barrier-based sync failed. "
 194                                       "disabling barriers\n");
 195                         nilfs_clear_opt(sbi, BARRIER);
 196                         goto retry;
 197                 }
 198         } else {
 199                 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
 200         }
 201
 202         if (unlikely(err)) {
 203                 printk(KERN_ERR
 204                        "NILFS: unable to write superblock (err=%d)\n", err);
 205                 if (err == -EIO && nilfs->ns_sbh[1]) {
 206                         /*
 207                          * sbp[0] points to newer log than sbp[1],
 208                          * so copy sbp[0] to sbp[1] to take over sbp[0].
 209                          */
 210                         memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
 211                                nilfs->ns_sbsize);
 212                         nilfs_fall_back_super_block(nilfs);
 213                         goto retry;
 214                 }
 215         } else {
 216                 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
 217
 218                 nilfs->ns_sbwcount++;
 219
 220                 /*
 221                  * The latest segment becomes trailable from the position
 222                  * written in superblock.
 223                  */
 224                 clear_nilfs_discontinued(nilfs);
 225
 226                 /* update GC protection for recent segments */
 227                 if (nilfs->ns_sbh[1]) {
 228                         if (flag == NILFS_SB_COMMIT_ALL) {
 229                                 set_buffer_dirty(nilfs->ns_sbh[1]);
 230                                 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
 231                                         goto out;
 232                         }
 233                         if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
 234                             le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
 235                                 sbp = nilfs->ns_sbp[1];
 236                 }
 237
 238                 spin_lock(&nilfs->ns_last_segment_lock);
 239                 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
 240                 spin_unlock(&nilfs->ns_last_segment_lock);
 241         }
 242  out:
 243         return err;
 244 }
 245
 246 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
 247                           struct the_nilfs *nilfs)
 248 {
 249         sector_t nfreeblocks;
 250
 251         /* nilfs->ns_sem must be locked by the caller. */
 252         nilfs_count_free_blocks(nilfs, &nfreeblocks);
 253         sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
 254
 255         spin_lock(&nilfs->ns_last_segment_lock);
 256         sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
 257         sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
 258         sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
 259         spin_unlock(&nilfs->ns_last_segment_lock);
 260 }
 261
 262 struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *sbi,
 263                                                int flip)
 264 {
 265         struct the_nilfs *nilfs = sbi->s_nilfs;
 266         struct nilfs_super_block **sbp = nilfs->ns_sbp;
 267
 268         /* nilfs->ns_sem must be locked by the caller. */
 269         if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
 270                 if (sbp[1] &&
 271                     sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
 272                         memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
 273                 } else {
 274                         printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
 275                                sbi->s_super->s_id);
 276                         return NULL;
 277                 }
 278         } else if (sbp[1] &&
 279                    sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
 280                         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
 281         }
 282
 283         if (flip && sbp[1])
 284                 nilfs_swap_super_block(nilfs);
 285
 286         return sbp;
 287 }
 288
 289 int nilfs_commit_super(struct nilfs_sb_info *sbi, int flag)
 290 {
 291         struct the_nilfs *nilfs = sbi->s_nilfs;
 292         struct nilfs_super_block **sbp = nilfs->ns_sbp;
 293         time_t t;
 294
 295         /* nilfs->ns_sem must be locked by the caller. */
 296         t = get_seconds();
 297         nilfs->ns_sbwtime = t;
 298         sbp[0]->s_wtime = cpu_to_le64(t);
 299         sbp[0]->s_sum = 0;
 300         sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
 301                                              (unsigned char *)sbp[0],
 302                                              nilfs->ns_sbsize));
 303         if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
 304                 sbp[1]->s_wtime = sbp[0]->s_wtime;
 305                 sbp[1]->s_sum = 0;
 306                 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
 307                                             (unsigned char *)sbp[1],
 308                                             nilfs->ns_sbsize));
 309         }
 310         clear_nilfs_sb_dirty(nilfs);
 311         return nilfs_sync_super(sbi, flag);
 312 }
 313
 314 /**
 315  * nilfs_cleanup_super() - write filesystem state for cleanup
 316  * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
 317  *
 318  * This function restores state flags in the on-disk super block.
 319  * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
 320  * filesystem was not clean previously.
 321  */
 322 int nilfs_cleanup_super(struct nilfs_sb_info *sbi)
 323 {
 324         struct nilfs_super_block **sbp;
 325         int flag = NILFS_SB_COMMIT;
 326         int ret = -EIO;
 327
 328         sbp = nilfs_prepare_super(sbi, 0);
 329         if (sbp) {
 330                 sbp[0]->s_state = cpu_to_le16(sbi->s_nilfs->ns_mount_state);
 331                 nilfs_set_log_cursor(sbp[0], sbi->s_nilfs);
 332                 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
 333                         /*
 334                          * make the "clean" flag also to the opposite
 335                          * super block if both super blocks point to
 336                          * the same checkpoint.
 337                          */
 338                         sbp[1]->s_state = sbp[0]->s_state;
 339                         flag = NILFS_SB_COMMIT_ALL;
 340                 }
 341                 ret = nilfs_commit_super(sbi, flag);
 342         }
 343         return ret;
 344 }
 345
 346 static void nilfs_put_super(struct super_block *sb)
 347 {
 348         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 349         struct the_nilfs *nilfs = sbi->s_nilfs;
 350
 351         nilfs_detach_segment_constructor(sbi);
 352
 353         if (!(sb->s_flags & MS_RDONLY)) {
 354                 down_write(&nilfs->ns_sem);
 355                 nilfs_cleanup_super(sbi);
 356                 up_write(&nilfs->ns_sem);
 357         }
 358         down_write(&nilfs->ns_super_sem);
 359         if (nilfs->ns_current == sbi)
 360                 nilfs->ns_current = NULL;
 361         list_del_init(&sbi->s_list);
 362         up_write(&nilfs->ns_super_sem);
 363
 364         put_nilfs(sbi->s_nilfs);
 365         sbi->s_super = NULL;
 366         sb->s_fs_info = NULL;
 367         nilfs_put_sbinfo(sbi);
 368 }
 369
 370 static int nilfs_sync_fs(struct super_block *sb, int wait)
 371 {
 372         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 373         struct the_nilfs *nilfs = sbi->s_nilfs;
 374         struct nilfs_super_block **sbp;
 375         int err = 0;
 376
 377         /* This function is called when super block should be written back */
 378         if (wait)
 379                 err = nilfs_construct_segment(sb);
 380
 381         down_write(&nilfs->ns_sem);
 382         if (nilfs_sb_dirty(nilfs)) {
 383                 sbp = nilfs_prepare_super(sbi, nilfs_sb_will_flip(nilfs));
 384                 if (likely(sbp)) {
 385                         nilfs_set_log_cursor(sbp[0], nilfs);
 386                         nilfs_commit_super(sbi, NILFS_SB_COMMIT);
 387                 }
 388         }
 389         up_write(&nilfs->ns_sem);
 390
 391         return err;
 392 }
 393
 394 int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno, int curr_mnt,
 395                             struct nilfs_root **rootp)
 396 {
 397         struct the_nilfs *nilfs = sbi->s_nilfs;
 398         struct nilfs_root *root;
 399         struct nilfs_checkpoint *raw_cp;
 400         struct buffer_head *bh_cp;
 401         int err = -ENOMEM;
 402
 403         root = nilfs_find_or_create_root(
 404                 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
 405         if (!root)
 406                 return err;
 407
 408         if (root->ifile)
 409                 goto reuse; /* already attached checkpoint */
 410
 411         root->ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
 412         if (!root->ifile)
 413                 goto failed;
 414
 415         down_read(&nilfs->ns_segctor_sem);
 416         err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
 417                                           &bh_cp);
 418         up_read(&nilfs->ns_segctor_sem);
 419         if (unlikely(err)) {
 420                 if (err == -ENOENT || err == -EINVAL) {
 421                         printk(KERN_ERR
 422                                "NILFS: Invalid checkpoint "
 423                                "(checkpoint number=%llu)\n",
 424                                (unsigned long long)cno);
 425                         err = -EINVAL;
 426                 }
 427                 goto failed;
 428         }
 429         err = nilfs_read_inode_common(root->ifile, &raw_cp->cp_ifile_inode);
 430         if (unlikely(err))
 431                 goto failed_bh;
 432         atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
 433         atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
 434
 435         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
 436
 437  reuse:
 438         *rootp = root;
 439         return 0;
 440
 441  failed_bh:
 442         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
 443  failed:
 444         nilfs_put_root(root);
 445
 446         return err;
 447 }
 448
 449 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 450 {
 451         struct super_block *sb = dentry->d_sb;
 452         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 453         struct the_nilfs *nilfs = sbi->s_nilfs;
 454         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 455         unsigned long long blocks;
 456         unsigned long overhead;
 457         unsigned long nrsvblocks;
 458         sector_t nfreeblocks;
 459         int err;
 460
 461         /*
 462          * Compute all of the segment blocks
 463          *
 464          * The blocks before first segment and after last segment
 465          * are excluded.
 466          */
 467         blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
 468                 - nilfs->ns_first_data_block;
 469         nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
 470
 471         /*
 472          * Compute the overhead
 473          *
 474          * When distributing meta data blocks outside segment structure,
 475          * We must count them as the overhead.
 476          */
 477         overhead = 0;
 478
 479         err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
 480         if (unlikely(err))
 481                 return err;
 482
 483         buf->f_type = NILFS_SUPER_MAGIC;
 484         buf->f_bsize = sb->s_blocksize;
 485         buf->f_blocks = blocks - overhead;
 486         buf->f_bfree = nfreeblocks;
 487         buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
 488                 (buf->f_bfree - nrsvblocks) : 0;
 489         buf->f_files = atomic_read(&sbi->s_inodes_count);
 490         buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
 491         buf->f_namelen = NILFS_NAME_LEN;
 492         buf->f_fsid.val[0] = (u32)id;
 493         buf->f_fsid.val[1] = (u32)(id >> 32);
 494
 495         return 0;
 496 }
 497
 498 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
 499 {
 500         struct super_block *sb = vfs->mnt_sb;
 501         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 502
 503         if (!nilfs_test_opt(sbi, BARRIER))
 504                 seq_puts(seq, ",nobarrier");
 505         if (nilfs_test_opt(sbi, SNAPSHOT))
 506                 seq_printf(seq, ",cp=%llu",
 507                            (unsigned long long int)sbi->s_snapshot_cno);
 508         if (nilfs_test_opt(sbi, ERRORS_PANIC))
 509                 seq_puts(seq, ",errors=panic");
 510         if (nilfs_test_opt(sbi, ERRORS_CONT))
 511                 seq_puts(seq, ",errors=continue");
 512         if (nilfs_test_opt(sbi, STRICT_ORDER))
 513                 seq_puts(seq, ",order=strict");
 514         if (nilfs_test_opt(sbi, NORECOVERY))
 515                 seq_puts(seq, ",norecovery");
 516         if (nilfs_test_opt(sbi, DISCARD))
 517                 seq_puts(seq, ",discard");
 518
 519         return 0;
 520 }
 521
 522 static const struct super_operations nilfs_sops = {
 523         .alloc_inode    = nilfs_alloc_inode,
 524         .destroy_inode  = nilfs_destroy_inode,
 525         .dirty_inode    = nilfs_dirty_inode,
 526         /* .write_inode    = nilfs_write_inode, */
 527         /* .put_inode      = nilfs_put_inode, */
 528         /* .drop_inode    = nilfs_drop_inode, */
 529         .evict_inode    = nilfs_evict_inode,
 530         .put_super      = nilfs_put_super,
 531         /* .write_super    = nilfs_write_super, */
 532         .sync_fs        = nilfs_sync_fs,
 533         /* .write_super_lockfs */
 534         /* .unlockfs */
 535         .statfs         = nilfs_statfs,
 536         .remount_fs     = nilfs_remount,
 537         /* .umount_begin */
 538         .show_options = nilfs_show_options
 539 };
 540
 541 enum {
 542         Opt_err_cont, Opt_err_panic, Opt_err_ro,
 543         Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
 544         Opt_discard, Opt_nodiscard, Opt_err,
 545 };
 546
 547 static match_table_t tokens = {
 548         {Opt_err_cont, "errors=continue"},
 549         {Opt_err_panic, "errors=panic"},
 550         {Opt_err_ro, "errors=remount-ro"},
 551         {Opt_barrier, "barrier"},
 552         {Opt_nobarrier, "nobarrier"},
 553         {Opt_snapshot, "cp=%u"},
 554         {Opt_order, "order=%s"},
 555         {Opt_norecovery, "norecovery"},
 556         {Opt_discard, "discard"},
 557         {Opt_nodiscard, "nodiscard"},
 558         {Opt_err, NULL}
 559 };
 560
 561 static int parse_options(char *options, struct super_block *sb, int is_remount)
 562 {
 563         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 564         char *p;
 565         substring_t args[MAX_OPT_ARGS];
 566         int option;
 567
 568         if (!options)
 569                 return 1;
 570
 571         while ((p = strsep(&options, ",")) != NULL) {
 572                 int token;
 573                 if (!*p)
 574                         continue;
 575
 576                 token = match_token(p, tokens, args);
 577                 switch (token) {
 578                 case Opt_barrier:
 579                         nilfs_set_opt(sbi, BARRIER);
 580                         break;
 581                 case Opt_nobarrier:
 582                         nilfs_clear_opt(sbi, BARRIER);
 583                         break;
 584                 case Opt_order:
 585                         if (strcmp(args[0].from, "relaxed") == 0)
 586                                 /* Ordered data semantics */
 587                                 nilfs_clear_opt(sbi, STRICT_ORDER);
 588                         else if (strcmp(args[0].from, "strict") == 0)
 589                                 /* Strict in-order semantics */
 590                                 nilfs_set_opt(sbi, STRICT_ORDER);
 591                         else
 592                                 return 0;
 593                         break;
 594                 case Opt_err_panic:
 595                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
 596                         break;
 597                 case Opt_err_ro:
 598                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
 599                         break;
 600                 case Opt_err_cont:
 601                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
 602                         break;
 603                 case Opt_snapshot:
 604                         if (match_int(&args[0], &option) || option <= 0)
 605                                 return 0;
 606                         if (is_remount) {
 607                                 if (!nilfs_test_opt(sbi, SNAPSHOT)) {
 608                                         printk(KERN_ERR
 609                                                "NILFS: cannot change regular "
 610                                                "mount to snapshot.\n");
 611                                         return 0;
 612                                 } else if (option != sbi->s_snapshot_cno) {
 613                                         printk(KERN_ERR
 614                                                "NILFS: cannot remount to a "
 615                                                "different snapshot.\n");
 616                                         return 0;
 617                                 }
 618                                 break;
 619                         }
 620                         if (!(sb->s_flags & MS_RDONLY)) {
 621                                 printk(KERN_ERR "NILFS: cannot mount snapshot "
 622                                        "read/write.  A read-only option is "
 623                                        "required.\n");
 624                                 return 0;
 625                         }
 626                         sbi->s_snapshot_cno = option;
 627                         nilfs_set_opt(sbi, SNAPSHOT);
 628                         break;
 629                 case Opt_norecovery:
 630                         nilfs_set_opt(sbi, NORECOVERY);
 631                         break;
 632                 case Opt_discard:
 633                         nilfs_set_opt(sbi, DISCARD);
 634                         break;
 635                 case Opt_nodiscard:
 636                         nilfs_clear_opt(sbi, DISCARD);
 637                         break;
 638                 default:
 639                         printk(KERN_ERR
 640                                "NILFS: Unrecognized mount option \"%s\"\n", p);
 641                         return 0;
 642                 }
 643         }
 644         return 1;
 645 }
 646
 647 static inline void
 648 nilfs_set_default_options(struct nilfs_sb_info *sbi,
 649                           struct nilfs_super_block *sbp)
 650 {
 651         sbi->s_mount_opt =
 652                 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
 653 }
 654
 655 static int nilfs_setup_super(struct nilfs_sb_info *sbi)
 656 {
 657         struct the_nilfs *nilfs = sbi->s_nilfs;
 658         struct nilfs_super_block **sbp;
 659         int max_mnt_count;
 660         int mnt_count;
 661
 662         /* nilfs->ns_sem must be locked by the caller. */
 663         sbp = nilfs_prepare_super(sbi, 0);
 664         if (!sbp)
 665                 return -EIO;
 666
 667         max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
 668         mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
 669
 670         if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
 671                 printk(KERN_WARNING
 672                        "NILFS warning: mounting fs with errors\n");
 673 #if 0
 674         } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
 675                 printk(KERN_WARNING
 676                        "NILFS warning: maximal mount count reached\n");
 677 #endif
 678         }
 679         if (!max_mnt_count)
 680                 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
 681
 682         sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
 683         sbp[0]->s_state =
 684                 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
 685         sbp[0]->s_mtime = cpu_to_le64(get_seconds());
 686         /* synchronize sbp[1] with sbp[0] */
 687         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
 688         return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
 689 }
 690
 691 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
 692                                                  u64 pos, int blocksize,
 693                                                  struct buffer_head **pbh)
 694 {
 695         unsigned long long sb_index = pos;
 696         unsigned long offset;
 697
 698         offset = do_div(sb_index, blocksize);
 699         *pbh = sb_bread(sb, sb_index);
 700         if (!*pbh)
 701                 return NULL;
 702         return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
 703 }
 704
 705 int nilfs_store_magic_and_option(struct super_block *sb,
 706                                  struct nilfs_super_block *sbp,
 707                                  char *data)
 708 {
 709         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 710
 711         sb->s_magic = le16_to_cpu(sbp->s_magic);
 712
 713         /* FS independent flags */
 714 #ifdef NILFS_ATIME_DISABLE
 715         sb->s_flags |= MS_NOATIME;
 716 #endif
 717
 718         nilfs_set_default_options(sbi, sbp);
 719
 720         sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
 721         sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
 722         sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
 723         sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
 724
 725         return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
 726 }
 727
 728 int nilfs_check_feature_compatibility(struct super_block *sb,
 729                                       struct nilfs_super_block *sbp)
 730 {
 731         __u64 features;
 732
 733         features = le64_to_cpu(sbp->s_feature_incompat) &
 734                 ~NILFS_FEATURE_INCOMPAT_SUPP;
 735         if (features) {
 736                 printk(KERN_ERR "NILFS: couldn't mount because of unsupported "
 737                        "optional features (%llx)\n",
 738                        (unsigned long long)features);
 739                 return -EINVAL;
 740         }
 741         features = le64_to_cpu(sbp->s_feature_compat_ro) &
 742                 ~NILFS_FEATURE_COMPAT_RO_SUPP;
 743         if (!(sb->s_flags & MS_RDONLY) && features) {
 744                 printk(KERN_ERR "NILFS: couldn't mount RDWR because of "
 745                        "unsupported optional features (%llx)\n",
 746                        (unsigned long long)features);
 747                 return -EINVAL;
 748         }
 749         return 0;
 750 }
 751
 752 /**
 753  * nilfs_fill_super() - initialize a super block instance
 754  * @sb: super_block
 755  * @data: mount options
 756  * @silent: silent mode flag
 757  * @nilfs: the_nilfs struct
 758  *
 759  * This function is called exclusively by nilfs->ns_mount_mutex.
 760  * So, the recovery process is protected from other simultaneous mounts.
 761  */
 762 static int
 763 nilfs_fill_super(struct super_block *sb, void *data, int silent,
 764                  struct the_nilfs *nilfs)
 765 {
 766         struct nilfs_sb_info *sbi;
 767         struct nilfs_root *fsroot;
 768         struct inode *root;
 769         __u64 cno;
 770         int err, curr_mnt;
 771
 772         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 773         if (!sbi)
 774                 return -ENOMEM;
 775
 776         sb->s_fs_info = sbi;
 777
 778         get_nilfs(nilfs);
 779         sbi->s_nilfs = nilfs;
 780         sbi->s_super = sb;
 781         atomic_set(&sbi->s_count, 1);
 782
 783         err = init_nilfs(nilfs, sbi, (char *)data);
 784         if (err)
 785                 goto failed_sbi;
 786
 787         spin_lock_init(&sbi->s_inode_lock);
 788         INIT_LIST_HEAD(&sbi->s_dirty_files);
 789         INIT_LIST_HEAD(&sbi->s_list);
 790
 791         /*
 792          * Following initialization is overlapped because
 793          * nilfs_sb_info structure has been cleared at the beginning.
 794          * But we reserve them to keep our interest and make ready
 795          * for the future change.
 796          */
 797         get_random_bytes(&sbi->s_next_generation,
 798                          sizeof(sbi->s_next_generation));
 799         spin_lock_init(&sbi->s_next_gen_lock);
 800
 801         sb->s_op = &nilfs_sops;
 802         sb->s_export_op = &nilfs_export_ops;
 803         sb->s_root = NULL;
 804         sb->s_time_gran = 1;
 805         sb->s_bdi = nilfs->ns_bdi;
 806
 807         err = load_nilfs(nilfs, sbi);
 808         if (err)
 809                 goto failed_sbi;
 810
 811         cno = nilfs_last_cno(nilfs);
 812         curr_mnt = true;
 813
 814         if (sb->s_flags & MS_RDONLY) {
 815                 if (nilfs_test_opt(sbi, SNAPSHOT)) {
 816                         down_read(&nilfs->ns_segctor_sem);
 817                         err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
 818                                                        sbi->s_snapshot_cno);
 819                         up_read(&nilfs->ns_segctor_sem);
 820                         if (err < 0) {
 821                                 if (err == -ENOENT)
 822                                         err = -EINVAL;
 823                                 goto failed_sbi;
 824                         }
 825                         if (!err) {
 826                                 printk(KERN_ERR
 827                                        "NILFS: The specified checkpoint is "
 828                                        "not a snapshot "
 829                                        "(checkpoint number=%llu).\n",
 830                                        (unsigned long long)sbi->s_snapshot_cno);
 831                                 err = -EINVAL;
 832                                 goto failed_sbi;
 833                         }
 834                         cno = sbi->s_snapshot_cno;
 835                         curr_mnt = false;
 836                 }
 837         }
 838
 839         err = nilfs_attach_checkpoint(sbi, cno, curr_mnt, &fsroot);
 840         if (err) {
 841                 printk(KERN_ERR "NILFS: error loading a checkpoint"
 842                        " (checkpoint number=%llu).\n", (unsigned long long)cno);
 843                 goto failed_sbi;
 844         }
 845
 846         if (!(sb->s_flags & MS_RDONLY)) {
 847                 err = nilfs_attach_segment_constructor(sbi, fsroot);
 848                 if (err)
 849                         goto failed_checkpoint;
 850         }
 851
 852         root = nilfs_iget(sb, fsroot, NILFS_ROOT_INO);
 853         if (IS_ERR(root)) {
 854                 printk(KERN_ERR "NILFS: get root inode failed\n");
 855                 err = PTR_ERR(root);
 856                 goto failed_segctor;
 857         }
 858         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
 859                 iput(root);
 860                 printk(KERN_ERR "NILFS: corrupt root inode.\n");
 861                 err = -EINVAL;
 862                 goto failed_segctor;
 863         }
 864         sb->s_root = d_alloc_root(root);
 865         if (!sb->s_root) {
 866                 iput(root);
 867                 printk(KERN_ERR "NILFS: get root dentry failed\n");
 868                 err = -ENOMEM;
 869                 goto failed_segctor;
 870         }
 871
 872         nilfs_put_root(fsroot);
 873
 874         if (!(sb->s_flags & MS_RDONLY)) {
 875                 down_write(&nilfs->ns_sem);
 876                 nilfs_setup_super(sbi);
 877                 up_write(&nilfs->ns_sem);
 878         }
 879
 880         down_write(&nilfs->ns_super_sem);
 881         list_add(&sbi->s_list, &nilfs->ns_supers);
 882         if (!nilfs_test_opt(sbi, SNAPSHOT))
 883                 nilfs->ns_current = sbi;
 884         up_write(&nilfs->ns_super_sem);
 885
 886         return 0;
 887
 888  failed_segctor:
 889         nilfs_detach_segment_constructor(sbi);
 890
 891  failed_checkpoint:
 892         nilfs_put_root(fsroot);
 893
 894  failed_sbi:
 895         put_nilfs(nilfs);
 896         sb->s_fs_info = NULL;
 897         nilfs_put_sbinfo(sbi);
 898         return err;
 899 }
 900
 901 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
 902 {
 903         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 904         struct the_nilfs *nilfs = sbi->s_nilfs;
 905         unsigned long old_sb_flags;
 906         struct nilfs_mount_options old_opts;
 907         int was_snapshot, err;
 908
 909         down_write(&nilfs->ns_super_sem);
 910         old_sb_flags = sb->s_flags;
 911         old_opts.mount_opt = sbi->s_mount_opt;
 912         old_opts.snapshot_cno = sbi->s_snapshot_cno;
 913         was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
 914
 915         if (!parse_options(data, sb, 1)) {
 916                 err = -EINVAL;
 917                 goto restore_opts;
 918         }
 919         sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
 920
 921         err = -EINVAL;
 922         if (was_snapshot && !(*flags & MS_RDONLY)) {
 923                 printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
 924                        "read/write.\n", sb->s_id);
 925                 goto restore_opts;
 926         }
 927
 928         if (!nilfs_valid_fs(nilfs)) {
 929                 printk(KERN_WARNING "NILFS (device %s): couldn't "
 930                        "remount because the filesystem is in an "
 931                        "incomplete recovery state.\n", sb->s_id);
 932                 goto restore_opts;
 933         }
 934
 935         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 936                 goto out;
 937         if (*flags & MS_RDONLY) {
 938                 /* Shutting down the segment constructor */
 939                 nilfs_detach_segment_constructor(sbi);
 940                 sb->s_flags |= MS_RDONLY;
 941
 942                 /*
 943                  * Remounting a valid RW partition RDONLY, so set
 944                  * the RDONLY flag and then mark the partition as valid again.
 945                  */
 946                 down_write(&nilfs->ns_sem);
 947                 nilfs_cleanup_super(sbi);
 948                 up_write(&nilfs->ns_sem);
 949         } else {
 950                 __u64 features;
 951                 struct nilfs_root *root;
 952
 953                 /*
 954                  * Mounting a RDONLY partition read-write, so reread and
 955                  * store the current valid flag.  (It may have been changed
 956                  * by fsck since we originally mounted the partition.)
 957                  */
 958                 down_read(&nilfs->ns_sem);
 959                 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
 960                         ~NILFS_FEATURE_COMPAT_RO_SUPP;
 961                 up_read(&nilfs->ns_sem);
 962                 if (features) {
 963                         printk(KERN_WARNING "NILFS (device %s): couldn't "
 964                                "remount RDWR because of unsupported optional "
 965                                "features (%llx)\n",
 966                                sb->s_id, (unsigned long long)features);
 967                         err = -EROFS;
 968                         goto restore_opts;
 969                 }
 970
 971                 sb->s_flags &= ~MS_RDONLY;
 972
 973                 root = NILFS_I(sb->s_root->d_inode)->i_root;
 974                 err = nilfs_attach_segment_constructor(sbi, root);
 975                 if (err)
 976                         goto restore_opts;
 977
 978                 down_write(&nilfs->ns_sem);
 979                 nilfs_setup_super(sbi);
 980                 up_write(&nilfs->ns_sem);
 981         }
 982  out:
 983         up_write(&nilfs->ns_super_sem);
 984         return 0;
 985
 986  restore_opts:
 987         sb->s_flags = old_sb_flags;
 988         sbi->s_mount_opt = old_opts.mount_opt;
 989         sbi->s_snapshot_cno = old_opts.snapshot_cno;
 990         up_write(&nilfs->ns_super_sem);
 991         return err;
 992 }
 993
 994 struct nilfs_super_data {
 995         struct block_device *bdev;
 996         struct nilfs_sb_info *sbi;
 997         __u64 cno;
 998         int flags;
 999 };
1000
1001 /**
1002  * nilfs_identify - pre-read mount options needed to identify mount instance
1003  * @data: mount options
1004  * @sd: nilfs_super_data
1005  */
1006 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1007 {
1008         char *p, *options = data;
1009         substring_t args[MAX_OPT_ARGS];
1010         int option, token;
1011         int ret = 0;
1012
1013         do {
1014                 p = strsep(&options, ",");
1015                 if (p != NULL && *p) {
1016                         token = match_token(p, tokens, args);
1017                         if (token == Opt_snapshot) {
1018                                 if (!(sd->flags & MS_RDONLY))
1019                                         ret++;
1020                                 else {
1021                                         ret = match_int(&args[0], &option);
1022                                         if (!ret) {
1023                                                 if (option > 0)
1024                                                         sd->cno = option;
1025                                                 else
1026                                                         ret++;
1027                                         }
1028                                 }
1029                         }
1030                         if (ret)
1031                                 printk(KERN_ERR
1032                                        "NILFS: invalid mount option: %s\n", p);
1033                 }
1034                 if (!options)
1035                         break;
1036                 BUG_ON(options == data);
1037                 *(options - 1) = ',';
1038         } while (!ret);
1039         return ret;
1040 }
1041
1042 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1043 {
1044         struct nilfs_super_data *sd = data;
1045
1046         s->s_bdev = sd->bdev;
1047         s->s_dev = s->s_bdev->bd_dev;
1048         return 0;
1049 }
1050
1051 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1052 {
1053         struct nilfs_super_data *sd = data;
1054
1055         return sd->sbi && s->s_fs_info == (void *)sd->sbi;
1056 }
1057
1058 static int
1059 nilfs_get_sb(struct file_system_type *fs_type, int flags,
1060              const char *dev_name, void *data, struct vfsmount *mnt)
1061 {
1062         struct nilfs_super_data sd;
1063         struct super_block *s;
1064         fmode_t mode = FMODE_READ;
1065         struct the_nilfs *nilfs;
1066         int err, need_to_close = 1;
1067
1068         if (!(flags & MS_RDONLY))
1069                 mode |= FMODE_WRITE;
1070
1071         sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
1072         if (IS_ERR(sd.bdev))
1073                 return PTR_ERR(sd.bdev);
1074
1075         /*
1076          * To get mount instance using sget() vfs-routine, NILFS needs
1077          * much more information than normal filesystems to identify mount
1078          * instance.  For snapshot mounts, not only a mount type (ro-mount
1079          * or rw-mount) but also a checkpoint number is required.
1080          */
1081         sd.cno = 0;
1082         sd.flags = flags;
1083         if (nilfs_identify((char *)data, &sd)) {
1084                 err = -EINVAL;
1085                 goto failed;
1086         }
1087
1088         nilfs = find_or_create_nilfs(sd.bdev);
1089         if (!nilfs) {
1090                 err = -ENOMEM;
1091                 goto failed;
1092         }
1093
1094         mutex_lock(&nilfs->ns_mount_mutex);
1095
1096         if (!sd.cno) {
1097                 /*
1098                  * Check if an exclusive mount exists or not.
1099                  * Snapshot mounts coexist with a current mount
1100                  * (i.e. rw-mount or ro-mount), whereas rw-mount and
1101                  * ro-mount are mutually exclusive.
1102                  */
1103                 down_read(&nilfs->ns_super_sem);
1104                 if (nilfs->ns_current &&
1105                     ((nilfs->ns_current->s_super->s_flags ^ flags)
1106                      & MS_RDONLY)) {
1107                         up_read(&nilfs->ns_super_sem);
1108                         err = -EBUSY;
1109                         goto failed_unlock;
1110                 }
1111                 up_read(&nilfs->ns_super_sem);
1112         }
1113
1114         /*
1115          * Find existing nilfs_sb_info struct
1116          */
1117         sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1118
1119         /*
1120          * Get super block instance holding the nilfs_sb_info struct.
1121          * A new instance is allocated if no existing mount is present or
1122          * existing instance has been unmounted.
1123          */
1124         s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
1125         if (sd.sbi)
1126                 nilfs_put_sbinfo(sd.sbi);
1127
1128         if (IS_ERR(s)) {
1129                 err = PTR_ERR(s);
1130                 goto failed_unlock;
1131         }
1132
1133         if (!s->s_root) {
1134                 char b[BDEVNAME_SIZE];
1135
1136                 /* New superblock instance created */
1137                 s->s_flags = flags;
1138                 s->s_mode = mode;
1139                 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1140                 sb_set_blocksize(s, block_size(sd.bdev));
1141
1142                 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
1143                                        nilfs);
1144                 if (err)
1145                         goto cancel_new;
1146
1147                 s->s_flags |= MS_ACTIVE;
1148                 need_to_close = 0;
1149         }
1150
1151         mutex_unlock(&nilfs->ns_mount_mutex);
1152         put_nilfs(nilfs);
1153         if (need_to_close)
1154                 close_bdev_exclusive(sd.bdev, mode);
1155         simple_set_mnt(mnt, s);
1156         return 0;
1157
1158  failed_unlock:
1159         mutex_unlock(&nilfs->ns_mount_mutex);
1160         put_nilfs(nilfs);
1161  failed:
1162         close_bdev_exclusive(sd.bdev, mode);
1163         return err;
1164
1165  cancel_new:
1166         /* Abandoning the newly allocated superblock */
1167         mutex_unlock(&nilfs->ns_mount_mutex);
1168         put_nilfs(nilfs);
1169         deactivate_locked_super(s);
1170         /*
1171          * deactivate_locked_super() invokes close_bdev_exclusive().
1172          * We must finish all post-cleaning before this call;
1173          * put_nilfs() needs the block device.
1174          */
1175         return err;
1176 }
1177
1178 struct file_system_type nilfs_fs_type = {
1179         .owner    = THIS_MODULE,
1180         .name     = "nilfs2",
1181         .get_sb   = nilfs_get_sb,
1182         .kill_sb  = kill_block_super,
1183         .fs_flags = FS_REQUIRES_DEV,
1184 };
1185
1186 static void nilfs_inode_init_once(void *obj)
1187 {
1188         struct nilfs_inode_info *ii = obj;
1189
1190         INIT_LIST_HEAD(&ii->i_dirty);
1191 #ifdef CONFIG_NILFS_XATTR
1192         init_rwsem(&ii->xattr_sem);
1193 #endif
1194         nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
1195         ii->i_bmap = &ii->i_bmap_data;
1196         inode_init_once(&ii->vfs_inode);
1197 }
1198
1199 static void nilfs_segbuf_init_once(void *obj)
1200 {
1201         memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1202 }
1203
1204 static void nilfs_destroy_cachep(void)
1205 {
1206         if (nilfs_inode_cachep)
1207                 kmem_cache_destroy(nilfs_inode_cachep);
1208         if (nilfs_transaction_cachep)
1209                 kmem_cache_destroy(nilfs_transaction_cachep);
1210         if (nilfs_segbuf_cachep)
1211                 kmem_cache_destroy(nilfs_segbuf_cachep);
1212         if (nilfs_btree_path_cache)
1213                 kmem_cache_destroy(nilfs_btree_path_cache);
1214 }
1215
1216 static int __init nilfs_init_cachep(void)
1217 {
1218         nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1219                         sizeof(struct nilfs_inode_info), 0,
1220                         SLAB_RECLAIM_ACCOUNT, nilfs_inode_init_once);
1221         if (!nilfs_inode_cachep)
1222                 goto fail;
1223
1224         nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1225                         sizeof(struct nilfs_transaction_info), 0,
1226                         SLAB_RECLAIM_ACCOUNT, NULL);
1227         if (!nilfs_transaction_cachep)
1228                 goto fail;
1229
1230         nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1231                         sizeof(struct nilfs_segment_buffer), 0,
1232                         SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1233         if (!nilfs_segbuf_cachep)
1234                 goto fail;
1235
1236         nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1237                         sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1238                         0, 0, NULL);
1239         if (!nilfs_btree_path_cache)
1240                 goto fail;
1241
1242         return 0;
1243
1244 fail:
1245         nilfs_destroy_cachep();
1246         return -ENOMEM;
1247 }
1248
1249 static int __init init_nilfs_fs(void)
1250 {
1251         int err;
1252
1253         err = nilfs_init_cachep();
1254         if (err)
1255                 goto fail;
1256
1257         err = register_filesystem(&nilfs_fs_type);
1258         if (err)
1259                 goto free_cachep;
1260
1261         printk(KERN_INFO "NILFS version 2 loaded\n");
1262         return 0;
1263
1264 free_cachep:
1265         nilfs_destroy_cachep();
1266 fail:
1267         return err;
1268 }
1269
1270 static void __exit exit_nilfs_fs(void)
1271 {
1272         nilfs_destroy_cachep();
1273         unregister_filesystem(&nilfs_fs_type);
1274 }
1275
1276 module_init(init_nilfs_fs)
1277 module_exit(exit_nilfs_fs)