fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/jbd2.h>
  24 #include <linux/ext4_fs.h>
  25 #include <linux/ext4_jbd2.h>
  26 #include <linux/slab.h>
  27 #include <linux/init.h>
  28 #include <linux/blkdev.h>
  29 #include <linux/parser.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/buffer_head.h>
  32 #include <linux/exportfs.h>
  33 #include <linux/vfs.h>
  34 #include <linux/random.h>
  35 #include <linux/mount.h>
  36 #include <linux/namei.h>
  37 #include <linux/quotaops.h>
  38 #include <linux/seq_file.h>
  39
  40 #include <asm/uaccess.h>
  41
  42 #include "xattr.h"
  43 #include "acl.h"
  44 #include "namei.h"
  45
  46 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  47                              unsigned long journal_devnum);
  48 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  49                                unsigned int);
  50 static void ext4_commit_super (struct super_block * sb,
  51                                struct ext4_super_block * es,
  52                                int sync);
  53 static void ext4_mark_recovery_complete(struct super_block * sb,
  54                                         struct ext4_super_block * es);
  55 static void ext4_clear_journal_err(struct super_block * sb,
  56                                    struct ext4_super_block * es);
  57 static int ext4_sync_fs(struct super_block *sb, int wait);
  58 static const char *ext4_decode_error(struct super_block * sb, int errno,
  59                                      char nbuf[16]);
  60 static int ext4_remount (struct super_block * sb, int * flags, char * data);
  61 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf);
  62 static void ext4_unlockfs(struct super_block *sb);
  63 static void ext4_write_super (struct super_block * sb);
  64 static void ext4_write_super_lockfs(struct super_block *sb);
  65
  66
  67 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  68                                struct ext4_group_desc *bg)
  69 {
  70         return le32_to_cpu(bg->bg_block_bitmap) |
  71                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  72                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  73 }
  74
  75 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  76                                struct ext4_group_desc *bg)
  77 {
  78         return le32_to_cpu(bg->bg_inode_bitmap) |
  79                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  80                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  81 }
  82
  83 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  84                               struct ext4_group_desc *bg)
  85 {
  86         return le32_to_cpu(bg->bg_inode_table) |
  87                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  88                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  89 }
  90
  91 void ext4_block_bitmap_set(struct super_block *sb,
  92                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
  93 {
  94         bg->bg_block_bitmap = cpu_to_le32((u32)blk);
  95         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
  96                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
  97 }
  98
  99 void ext4_inode_bitmap_set(struct super_block *sb,
 100                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 101 {
 102         bg->bg_inode_bitmap  = cpu_to_le32((u32)blk);
 103         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 104                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 105 }
 106
 107 void ext4_inode_table_set(struct super_block *sb,
 108                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 109 {
 110         bg->bg_inode_table = cpu_to_le32((u32)blk);
 111         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 112                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 113 }
 114
 115 /*
 116  * Wrappers for jbd2_journal_start/end.
 117  *
 118  * The only special thing we need to do here is to make sure that all
 119  * journal_end calls result in the superblock being marked dirty, so
 120  * that sync() will call the filesystem's write_super callback if
 121  * appropriate.
 122  */
 123 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 124 {
 125         journal_t *journal;
 126
 127         if (sb->s_flags & MS_RDONLY)
 128                 return ERR_PTR(-EROFS);
 129
 130         /* Special case here: if the journal has aborted behind our
 131          * backs (eg. EIO in the commit thread), then we still need to
 132          * take the FS itself readonly cleanly. */
 133         journal = EXT4_SB(sb)->s_journal;
 134         if (is_journal_aborted(journal)) {
 135                 ext4_abort(sb, __FUNCTION__,
 136                            "Detected aborted journal");
 137                 return ERR_PTR(-EROFS);
 138         }
 139
 140         return jbd2_journal_start(journal, nblocks);
 141 }
 142
 143 /*
 144  * The only special thing we need to do here is to make sure that all
 145  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 146  * that sync() will call the filesystem's write_super callback if
 147  * appropriate.
 148  */
 149 int __ext4_journal_stop(const char *where, handle_t *handle)
 150 {
 151         struct super_block *sb;
 152         int err;
 153         int rc;
 154
 155         sb = handle->h_transaction->t_journal->j_private;
 156         err = handle->h_err;
 157         rc = jbd2_journal_stop(handle);
 158
 159         if (!err)
 160                 err = rc;
 161         if (err)
 162                 __ext4_std_error(sb, where, err);
 163         return err;
 164 }
 165
 166 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 167                 struct buffer_head *bh, handle_t *handle, int err)
 168 {
 169         char nbuf[16];
 170         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 171
 172         if (bh)
 173                 BUFFER_TRACE(bh, "abort");
 174
 175         if (!handle->h_err)
 176                 handle->h_err = err;
 177
 178         if (is_handle_aborted(handle))
 179                 return;
 180
 181         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 182                caller, errstr, err_fn);
 183
 184         jbd2_journal_abort_handle(handle);
 185 }
 186
 187 /* Deal with the reporting of failure conditions on a filesystem such as
 188  * inconsistencies detected or read IO failures.
 189  *
 190  * On ext2, we can store the error state of the filesystem in the
 191  * superblock.  That is not possible on ext4, because we may have other
 192  * write ordering constraints on the superblock which prevent us from
 193  * writing it out straight away; and given that the journal is about to
 194  * be aborted, we can't rely on the current, or future, transactions to
 195  * write out the superblock safely.
 196  *
 197  * We'll just use the jbd2_journal_abort() error code to record an error in
 198  * the journal instead.  On recovery, the journal will compain about
 199  * that error until we've noted it down and cleared it.
 200  */
 201
 202 static void ext4_handle_error(struct super_block *sb)
 203 {
 204         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 205
 206         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 207         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 208
 209         if (sb->s_flags & MS_RDONLY)
 210                 return;
 211
 212         if (!test_opt (sb, ERRORS_CONT)) {
 213                 journal_t *journal = EXT4_SB(sb)->s_journal;
 214
 215                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 216                 if (journal)
 217                         jbd2_journal_abort(journal, -EIO);
 218         }
 219         if (test_opt (sb, ERRORS_RO)) {
 220                 printk (KERN_CRIT "Remounting filesystem read-only\n");
 221                 sb->s_flags |= MS_RDONLY;
 222         }
 223         ext4_commit_super(sb, es, 1);
 224         if (test_opt(sb, ERRORS_PANIC))
 225                 panic("EXT4-fs (device %s): panic forced after error\n",
 226                         sb->s_id);
 227 }
 228
 229 void ext4_error (struct super_block * sb, const char * function,
 230                  const char * fmt, ...)
 231 {
 232         va_list args;
 233
 234         va_start(args, fmt);
 235         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 236         vprintk(fmt, args);
 237         printk("\n");
 238         va_end(args);
 239
 240         ext4_handle_error(sb);
 241 }
 242
 243 static const char *ext4_decode_error(struct super_block * sb, int errno,
 244                                      char nbuf[16])
 245 {
 246         char *errstr = NULL;
 247
 248         switch (errno) {
 249         case -EIO:
 250                 errstr = "IO failure";
 251                 break;
 252         case -ENOMEM:
 253                 errstr = "Out of memory";
 254                 break;
 255         case -EROFS:
 256                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 257                         errstr = "Journal has aborted";
 258                 else
 259                         errstr = "Readonly filesystem";
 260                 break;
 261         default:
 262                 /* If the caller passed in an extra buffer for unknown
 263                  * errors, textualise them now.  Else we just return
 264                  * NULL. */
 265                 if (nbuf) {
 266                         /* Check for truncated error codes... */
 267                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 268                                 errstr = nbuf;
 269                 }
 270                 break;
 271         }
 272
 273         return errstr;
 274 }
 275
 276 /* __ext4_std_error decodes expected errors from journaling functions
 277  * automatically and invokes the appropriate error response.  */
 278
 279 void __ext4_std_error (struct super_block * sb, const char * function,
 280                        int errno)
 281 {
 282         char nbuf[16];
 283         const char *errstr;
 284
 285         /* Special case: if the error is EROFS, and we're not already
 286          * inside a transaction, then there's really no point in logging
 287          * an error. */
 288         if (errno == -EROFS && journal_current_handle() == NULL &&
 289             (sb->s_flags & MS_RDONLY))
 290                 return;
 291
 292         errstr = ext4_decode_error(sb, errno, nbuf);
 293         printk (KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 294                 sb->s_id, function, errstr);
 295
 296         ext4_handle_error(sb);
 297 }
 298
 299 /*
 300  * ext4_abort is a much stronger failure handler than ext4_error.  The
 301  * abort function may be used to deal with unrecoverable failures such
 302  * as journal IO errors or ENOMEM at a critical moment in log management.
 303  *
 304  * We unconditionally force the filesystem into an ABORT|READONLY state,
 305  * unless the error response on the fs has been set to panic in which
 306  * case we take the easy way out and panic immediately.
 307  */
 308
 309 void ext4_abort (struct super_block * sb, const char * function,
 310                  const char * fmt, ...)
 311 {
 312         va_list args;
 313
 314         printk (KERN_CRIT "ext4_abort called.\n");
 315
 316         va_start(args, fmt);
 317         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 318         vprintk(fmt, args);
 319         printk("\n");
 320         va_end(args);
 321
 322         if (test_opt(sb, ERRORS_PANIC))
 323                 panic("EXT4-fs panic from previous error\n");
 324
 325         if (sb->s_flags & MS_RDONLY)
 326                 return;
 327
 328         printk(KERN_CRIT "Remounting filesystem read-only\n");
 329         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 330         sb->s_flags |= MS_RDONLY;
 331         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 332         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 333 }
 334
 335 void ext4_warning (struct super_block * sb, const char * function,
 336                    const char * fmt, ...)
 337 {
 338         va_list args;
 339
 340         va_start(args, fmt);
 341         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 342                sb->s_id, function);
 343         vprintk(fmt, args);
 344         printk("\n");
 345         va_end(args);
 346 }
 347
 348 void ext4_update_dynamic_rev(struct super_block *sb)
 349 {
 350         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 351
 352         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 353                 return;
 354
 355         ext4_warning(sb, __FUNCTION__,
 356                      "updating to rev %d because of new feature flag, "
 357                      "running e2fsck is recommended",
 358                      EXT4_DYNAMIC_REV);
 359
 360         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 361         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 362         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 363         /* leave es->s_feature_*compat flags alone */
 364         /* es->s_uuid will be set by e2fsck if empty */
 365
 366         /*
 367          * The rest of the superblock fields should be zero, and if not it
 368          * means they are likely already in use, so leave them alone.  We
 369          * can leave it up to e2fsck to clean up any inconsistencies there.
 370          */
 371 }
 372
 373 /*
 374  * Open the external journal device
 375  */
 376 static struct block_device *ext4_blkdev_get(dev_t dev)
 377 {
 378         struct block_device *bdev;
 379         char b[BDEVNAME_SIZE];
 380
 381         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 382         if (IS_ERR(bdev))
 383                 goto fail;
 384         return bdev;
 385
 386 fail:
 387         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 388                         __bdevname(dev, b), PTR_ERR(bdev));
 389         return NULL;
 390 }
 391
 392 /*
 393  * Release the journal device
 394  */
 395 static int ext4_blkdev_put(struct block_device *bdev)
 396 {
 397         bd_release(bdev);
 398         return blkdev_put(bdev);
 399 }
 400
 401 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 402 {
 403         struct block_device *bdev;
 404         int ret = -ENODEV;
 405
 406         bdev = sbi->journal_bdev;
 407         if (bdev) {
 408                 ret = ext4_blkdev_put(bdev);
 409                 sbi->journal_bdev = NULL;
 410         }
 411         return ret;
 412 }
 413
 414 static inline struct inode *orphan_list_entry(struct list_head *l)
 415 {
 416         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 417 }
 418
 419 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 420 {
 421         struct list_head *l;
 422
 423         printk(KERN_ERR "sb orphan head is %d\n",
 424                le32_to_cpu(sbi->s_es->s_last_orphan));
 425
 426         printk(KERN_ERR "sb_info orphan list:\n");
 427         list_for_each(l, &sbi->s_orphan) {
 428                 struct inode *inode = orphan_list_entry(l);
 429                 printk(KERN_ERR "  "
 430                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 431                        inode->i_sb->s_id, inode->i_ino, inode,
 432                        inode->i_mode, inode->i_nlink,
 433                        NEXT_ORPHAN(inode));
 434         }
 435 }
 436
 437 static void ext4_put_super (struct super_block * sb)
 438 {
 439         struct ext4_sb_info *sbi = EXT4_SB(sb);
 440         struct ext4_super_block *es = sbi->s_es;
 441         int i;
 442
 443         ext4_ext_release(sb);
 444         ext4_xattr_put_super(sb);
 445         jbd2_journal_destroy(sbi->s_journal);
 446         if (!(sb->s_flags & MS_RDONLY)) {
 447                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 448                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 449                 BUFFER_TRACE(sbi->s_sbh, "marking dirty");
 450                 mark_buffer_dirty(sbi->s_sbh);
 451                 ext4_commit_super(sb, es, 1);
 452         }
 453
 454         for (i = 0; i < sbi->s_gdb_count; i++)
 455                 brelse(sbi->s_group_desc[i]);
 456         kfree(sbi->s_group_desc);
 457         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 458         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 459         percpu_counter_destroy(&sbi->s_dirs_counter);
 460         brelse(sbi->s_sbh);
 461 #ifdef CONFIG_QUOTA
 462         for (i = 0; i < MAXQUOTAS; i++)
 463                 kfree(sbi->s_qf_names[i]);
 464 #endif
 465
 466         /* Debugging code just in case the in-memory inode orphan list
 467          * isn't empty.  The on-disk one can be non-empty if we've
 468          * detected an error and taken the fs readonly, but the
 469          * in-memory list had better be clean by this point. */
 470         if (!list_empty(&sbi->s_orphan))
 471                 dump_orphan_list(sb, sbi);
 472         J_ASSERT(list_empty(&sbi->s_orphan));
 473
 474         invalidate_bdev(sb->s_bdev);
 475         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 476                 /*
 477                  * Invalidate the journal device's buffers.  We don't want them
 478                  * floating about in memory - the physical journal device may
 479                  * hotswapped, and it breaks the `ro-after' testing code.
 480                  */
 481                 sync_blockdev(sbi->journal_bdev);
 482                 invalidate_bdev(sbi->journal_bdev);
 483                 ext4_blkdev_remove(sbi);
 484         }
 485         sb->s_fs_info = NULL;
 486         kfree(sbi);
 487         return;
 488 }
 489
 490 static struct kmem_cache *ext4_inode_cachep;
 491
 492 /*
 493  * Called inside transaction, so use GFP_NOFS
 494  */
 495 static struct inode *ext4_alloc_inode(struct super_block *sb)
 496 {
 497         struct ext4_inode_info *ei;
 498
 499         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 500         if (!ei)
 501                 return NULL;
 502 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 503         ei->i_acl = EXT4_ACL_NOT_CACHED;
 504         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 505 #endif
 506         ei->i_block_alloc_info = NULL;
 507         ei->vfs_inode.i_version = 1;
 508         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 509         return &ei->vfs_inode;
 510 }
 511
 512 static void ext4_destroy_inode(struct inode *inode)
 513 {
 514         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 515                 printk("EXT4 Inode %p: orphan list check failed!\n",
 516                         EXT4_I(inode));
 517                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 518                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 519                                 true);
 520                 dump_stack();
 521         }
 522         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 523 }
 524
 525 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
 526 {
 527         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 528
 529         INIT_LIST_HEAD(&ei->i_orphan);
 530 #ifdef CONFIG_EXT4DEV_FS_XATTR
 531         init_rwsem(&ei->xattr_sem);
 532 #endif
 533         mutex_init(&ei->truncate_mutex);
 534         inode_init_once(&ei->vfs_inode);
 535 }
 536
 537 static int init_inodecache(void)
 538 {
 539         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 540                                              sizeof(struct ext4_inode_info),
 541                                              0, (SLAB_RECLAIM_ACCOUNT|
 542                                                 SLAB_MEM_SPREAD),
 543                                              init_once, NULL);
 544         if (ext4_inode_cachep == NULL)
 545                 return -ENOMEM;
 546         return 0;
 547 }
 548
 549 static void destroy_inodecache(void)
 550 {
 551         kmem_cache_destroy(ext4_inode_cachep);
 552 }
 553
 554 static void ext4_clear_inode(struct inode *inode)
 555 {
 556         struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
 557 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 558         if (EXT4_I(inode)->i_acl &&
 559                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 560                 posix_acl_release(EXT4_I(inode)->i_acl);
 561                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 562         }
 563         if (EXT4_I(inode)->i_default_acl &&
 564                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 565                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 566                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 567         }
 568 #endif
 569         ext4_discard_reservation(inode);
 570         EXT4_I(inode)->i_block_alloc_info = NULL;
 571         if (unlikely(rsv))
 572                 kfree(rsv);
 573 }
 574
 575 static inline void ext4_show_quota_options(struct seq_file *seq, struct super_block *sb)
 576 {
 577 #if defined(CONFIG_QUOTA)
 578         struct ext4_sb_info *sbi = EXT4_SB(sb);
 579
 580         if (sbi->s_jquota_fmt)
 581                 seq_printf(seq, ",jqfmt=%s",
 582                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");
 583
 584         if (sbi->s_qf_names[USRQUOTA])
 585                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 586
 587         if (sbi->s_qf_names[GRPQUOTA])
 588                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 589
 590         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 591                 seq_puts(seq, ",usrquota");
 592
 593         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 594                 seq_puts(seq, ",grpquota");
 595 #endif
 596 }
 597
 598 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 599 {
 600         struct super_block *sb = vfs->mnt_sb;
 601
 602         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 603                 seq_puts(seq, ",data=journal");
 604         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 605                 seq_puts(seq, ",data=ordered");
 606         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 607                 seq_puts(seq, ",data=writeback");
 608
 609         ext4_show_quota_options(seq, sb);
 610
 611         return 0;
 612 }
 613
 614
 615 static struct dentry *ext4_get_dentry(struct super_block *sb, void *vobjp)
 616 {
 617         __u32 *objp = vobjp;
 618         unsigned long ino = objp[0];
 619         __u32 generation = objp[1];
 620         struct inode *inode;
 621         struct dentry *result;
 622
 623         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 624                 return ERR_PTR(-ESTALE);
 625         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 626                 return ERR_PTR(-ESTALE);
 627
 628         /* iget isn't really right if the inode is currently unallocated!!
 629          *
 630          * ext4_read_inode will return a bad_inode if the inode had been
 631          * deleted, so we should be safe.
 632          *
 633          * Currently we don't know the generation for parent directory, so
 634          * a generation of 0 means "accept any"
 635          */
 636         inode = iget(sb, ino);
 637         if (inode == NULL)
 638                 return ERR_PTR(-ENOMEM);
 639         if (is_bad_inode(inode) ||
 640             (generation && inode->i_generation != generation)) {
 641                 iput(inode);
 642                 return ERR_PTR(-ESTALE);
 643         }
 644         /* now to find a dentry.
 645          * If possible, get a well-connected one
 646          */
 647         result = d_alloc_anon(inode);
 648         if (!result) {
 649                 iput(inode);
 650                 return ERR_PTR(-ENOMEM);
 651         }
 652         return result;
 653 }
 654
 655 #ifdef CONFIG_QUOTA
 656 #define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
 657 #define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 658
 659 static int ext4_dquot_initialize(struct inode *inode, int type);
 660 static int ext4_dquot_drop(struct inode *inode);
 661 static int ext4_write_dquot(struct dquot *dquot);
 662 static int ext4_acquire_dquot(struct dquot *dquot);
 663 static int ext4_release_dquot(struct dquot *dquot);
 664 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 665 static int ext4_write_info(struct super_block *sb, int type);
 666 static int ext4_quota_on(struct super_block *sb, int type, int format_id, char *path);
 667 static int ext4_quota_on_mount(struct super_block *sb, int type);
 668 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 669                                size_t len, loff_t off);
 670 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 671                                 const char *data, size_t len, loff_t off);
 672
 673 static struct dquot_operations ext4_quota_operations = {
 674         .initialize     = ext4_dquot_initialize,
 675         .drop           = ext4_dquot_drop,
 676         .alloc_space    = dquot_alloc_space,
 677         .alloc_inode    = dquot_alloc_inode,
 678         .free_space     = dquot_free_space,
 679         .free_inode     = dquot_free_inode,
 680         .transfer       = dquot_transfer,
 681         .write_dquot    = ext4_write_dquot,
 682         .acquire_dquot  = ext4_acquire_dquot,
 683         .release_dquot  = ext4_release_dquot,
 684         .mark_dirty     = ext4_mark_dquot_dirty,
 685         .write_info     = ext4_write_info
 686 };
 687
 688 static struct quotactl_ops ext4_qctl_operations = {
 689         .quota_on       = ext4_quota_on,
 690         .quota_off      = vfs_quota_off,
 691         .quota_sync     = vfs_quota_sync,
 692         .get_info       = vfs_get_dqinfo,
 693         .set_info       = vfs_set_dqinfo,
 694         .get_dqblk      = vfs_get_dqblk,
 695         .set_dqblk      = vfs_set_dqblk
 696 };
 697 #endif
 698
 699 static const struct super_operations ext4_sops = {
 700         .alloc_inode    = ext4_alloc_inode,
 701         .destroy_inode  = ext4_destroy_inode,
 702         .read_inode     = ext4_read_inode,
 703         .write_inode    = ext4_write_inode,
 704         .dirty_inode    = ext4_dirty_inode,
 705         .delete_inode   = ext4_delete_inode,
 706         .put_super      = ext4_put_super,
 707         .write_super    = ext4_write_super,
 708         .sync_fs        = ext4_sync_fs,
 709         .write_super_lockfs = ext4_write_super_lockfs,
 710         .unlockfs       = ext4_unlockfs,
 711         .statfs         = ext4_statfs,
 712         .remount_fs     = ext4_remount,
 713         .clear_inode    = ext4_clear_inode,
 714         .show_options   = ext4_show_options,
 715 #ifdef CONFIG_QUOTA
 716         .quota_read     = ext4_quota_read,
 717         .quota_write    = ext4_quota_write,
 718 #endif
 719 };
 720
 721 static struct export_operations ext4_export_ops = {
 722         .get_parent = ext4_get_parent,
 723         .get_dentry = ext4_get_dentry,
 724 };
 725
 726 enum {
 727         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 728         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 729         Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
 730         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 731         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 732         Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 733         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 734         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 735         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 736         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 737         Opt_grpquota, Opt_extents, Opt_noextents,
 738 };
 739
 740 static match_table_t tokens = {
 741         {Opt_bsd_df, "bsddf"},
 742         {Opt_minix_df, "minixdf"},
 743         {Opt_grpid, "grpid"},
 744         {Opt_grpid, "bsdgroups"},
 745         {Opt_nogrpid, "nogrpid"},
 746         {Opt_nogrpid, "sysvgroups"},
 747         {Opt_resgid, "resgid=%u"},
 748         {Opt_resuid, "resuid=%u"},
 749         {Opt_sb, "sb=%u"},
 750         {Opt_err_cont, "errors=continue"},
 751         {Opt_err_panic, "errors=panic"},
 752         {Opt_err_ro, "errors=remount-ro"},
 753         {Opt_nouid32, "nouid32"},
 754         {Opt_nocheck, "nocheck"},
 755         {Opt_nocheck, "check=none"},
 756         {Opt_debug, "debug"},
 757         {Opt_oldalloc, "oldalloc"},
 758         {Opt_orlov, "orlov"},
 759         {Opt_user_xattr, "user_xattr"},
 760         {Opt_nouser_xattr, "nouser_xattr"},
 761         {Opt_acl, "acl"},
 762         {Opt_noacl, "noacl"},
 763         {Opt_reservation, "reservation"},
 764         {Opt_noreservation, "noreservation"},
 765         {Opt_noload, "noload"},
 766         {Opt_nobh, "nobh"},
 767         {Opt_bh, "bh"},
 768         {Opt_commit, "commit=%u"},
 769         {Opt_journal_update, "journal=update"},
 770         {Opt_journal_inum, "journal=%u"},
 771         {Opt_journal_dev, "journal_dev=%u"},
 772         {Opt_abort, "abort"},
 773         {Opt_data_journal, "data=journal"},
 774         {Opt_data_ordered, "data=ordered"},
 775         {Opt_data_writeback, "data=writeback"},
 776         {Opt_offusrjquota, "usrjquota="},
 777         {Opt_usrjquota, "usrjquota=%s"},
 778         {Opt_offgrpjquota, "grpjquota="},
 779         {Opt_grpjquota, "grpjquota=%s"},
 780         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 781         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 782         {Opt_grpquota, "grpquota"},
 783         {Opt_noquota, "noquota"},
 784         {Opt_quota, "quota"},
 785         {Opt_usrquota, "usrquota"},
 786         {Opt_barrier, "barrier=%u"},
 787         {Opt_extents, "extents"},
 788         {Opt_noextents, "noextents"},
 789         {Opt_err, NULL},
 790         {Opt_resize, "resize"},
 791 };
 792
 793 static ext4_fsblk_t get_sb_block(void **data)
 794 {
 795         ext4_fsblk_t    sb_block;
 796         char            *options = (char *) *data;
 797
 798         if (!options || strncmp(options, "sb=", 3) != 0)
 799                 return 1;       /* Default location */
 800         options += 3;
 801         /*todo: use simple_strtoll with >32bit ext4 */
 802         sb_block = simple_strtoul(options, &options, 0);
 803         if (*options && *options != ',') {
 804                 printk("EXT4-fs: Invalid sb specification: %s\n",
 805                        (char *) *data);
 806                 return 1;
 807         }
 808         if (*options == ',')
 809                 options++;
 810         *data = (void *) options;
 811         return sb_block;
 812 }
 813
 814 static int parse_options (char *options, struct super_block *sb,
 815                           unsigned int *inum, unsigned long *journal_devnum,
 816                           ext4_fsblk_t *n_blocks_count, int is_remount)
 817 {
 818         struct ext4_sb_info *sbi = EXT4_SB(sb);
 819         char * p;
 820         substring_t args[MAX_OPT_ARGS];
 821         int data_opt = 0;
 822         int option;
 823 #ifdef CONFIG_QUOTA
 824         int qtype;
 825         char *qname;
 826 #endif
 827
 828         if (!options)
 829                 return 1;
 830
 831         while ((p = strsep (&options, ",")) != NULL) {
 832                 int token;
 833                 if (!*p)
 834                         continue;
 835
 836                 token = match_token(p, tokens, args);
 837                 switch (token) {
 838                 case Opt_bsd_df:
 839                         clear_opt (sbi->s_mount_opt, MINIX_DF);
 840                         break;
 841                 case Opt_minix_df:
 842                         set_opt (sbi->s_mount_opt, MINIX_DF);
 843                         break;
 844                 case Opt_grpid:
 845                         set_opt (sbi->s_mount_opt, GRPID);
 846                         break;
 847                 case Opt_nogrpid:
 848                         clear_opt (sbi->s_mount_opt, GRPID);
 849                         break;
 850                 case Opt_resuid:
 851                         if (match_int(&args[0], &option))
 852                                 return 0;
 853                         sbi->s_resuid = option;
 854                         break;
 855                 case Opt_resgid:
 856                         if (match_int(&args[0], &option))
 857                                 return 0;
 858                         sbi->s_resgid = option;
 859                         break;
 860                 case Opt_sb:
 861                         /* handled by get_sb_block() instead of here */
 862                         /* *sb_block = match_int(&args[0]); */
 863                         break;
 864                 case Opt_err_panic:
 865                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
 866                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
 867                         set_opt (sbi->s_mount_opt, ERRORS_PANIC);
 868                         break;
 869                 case Opt_err_ro:
 870                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
 871                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
 872                         set_opt (sbi->s_mount_opt, ERRORS_RO);
 873                         break;
 874                 case Opt_err_cont:
 875                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
 876                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
 877                         set_opt (sbi->s_mount_opt, ERRORS_CONT);
 878                         break;
 879                 case Opt_nouid32:
 880                         set_opt (sbi->s_mount_opt, NO_UID32);
 881                         break;
 882                 case Opt_nocheck:
 883                         clear_opt (sbi->s_mount_opt, CHECK);
 884                         break;
 885                 case Opt_debug:
 886                         set_opt (sbi->s_mount_opt, DEBUG);
 887                         break;
 888                 case Opt_oldalloc:
 889                         set_opt (sbi->s_mount_opt, OLDALLOC);
 890                         break;
 891                 case Opt_orlov:
 892                         clear_opt (sbi->s_mount_opt, OLDALLOC);
 893                         break;
 894 #ifdef CONFIG_EXT4DEV_FS_XATTR
 895                 case Opt_user_xattr:
 896                         set_opt (sbi->s_mount_opt, XATTR_USER);
 897                         break;
 898                 case Opt_nouser_xattr:
 899                         clear_opt (sbi->s_mount_opt, XATTR_USER);
 900                         break;
 901 #else
 902                 case Opt_user_xattr:
 903                 case Opt_nouser_xattr:
 904                         printk("EXT4 (no)user_xattr options not supported\n");
 905                         break;
 906 #endif
 907 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 908                 case Opt_acl:
 909                         set_opt(sbi->s_mount_opt, POSIX_ACL);
 910                         break;
 911                 case Opt_noacl:
 912                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
 913                         break;
 914 #else
 915                 case Opt_acl:
 916                 case Opt_noacl:
 917                         printk("EXT4 (no)acl options not supported\n");
 918                         break;
 919 #endif
 920                 case Opt_reservation:
 921                         set_opt(sbi->s_mount_opt, RESERVATION);
 922                         break;
 923                 case Opt_noreservation:
 924                         clear_opt(sbi->s_mount_opt, RESERVATION);
 925                         break;
 926                 case Opt_journal_update:
 927                         /* @@@ FIXME */
 928                         /* Eventually we will want to be able to create
 929                            a journal file here.  For now, only allow the
 930                            user to specify an existing inode to be the
 931                            journal file. */
 932                         if (is_remount) {
 933                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 934                                        "journal on remount\n");
 935                                 return 0;
 936                         }
 937                         set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
 938                         break;
 939                 case Opt_journal_inum:
 940                         if (is_remount) {
 941                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 942                                        "journal on remount\n");
 943                                 return 0;
 944                         }
 945                         if (match_int(&args[0], &option))
 946                                 return 0;
 947                         *inum = option;
 948                         break;
 949                 case Opt_journal_dev:
 950                         if (is_remount) {
 951                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 952                                        "journal on remount\n");
 953                                 return 0;
 954                         }
 955                         if (match_int(&args[0], &option))
 956                                 return 0;
 957                         *journal_devnum = option;
 958                         break;
 959                 case Opt_noload:
 960                         set_opt (sbi->s_mount_opt, NOLOAD);
 961                         break;
 962                 case Opt_commit:
 963                         if (match_int(&args[0], &option))
 964                                 return 0;
 965                         if (option < 0)
 966                                 return 0;
 967                         if (option == 0)
 968                                 option = JBD_DEFAULT_MAX_COMMIT_AGE;
 969                         sbi->s_commit_interval = HZ * option;
 970                         break;
 971                 case Opt_data_journal:
 972                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
 973                         goto datacheck;
 974                 case Opt_data_ordered:
 975                         data_opt = EXT4_MOUNT_ORDERED_DATA;
 976                         goto datacheck;
 977                 case Opt_data_writeback:
 978                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
 979                 datacheck:
 980                         if (is_remount) {
 981                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
 982                                                 != data_opt) {
 983                                         printk(KERN_ERR
 984                                                 "EXT4-fs: cannot change data "
 985                                                 "mode on remount\n");
 986                                         return 0;
 987                                 }
 988                         } else {
 989                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
 990                                 sbi->s_mount_opt |= data_opt;
 991                         }
 992                         break;
 993 #ifdef CONFIG_QUOTA
 994                 case Opt_usrjquota:
 995                         qtype = USRQUOTA;
 996                         goto set_qf_name;
 997                 case Opt_grpjquota:
 998                         qtype = GRPQUOTA;
 999 set_qf_name:
1000                         if (sb_any_quota_enabled(sb)) {
1001                                 printk(KERN_ERR
1002                                         "EXT4-fs: Cannot change journalled "
1003                                         "quota options when quota turned on.\n");
1004                                 return 0;
1005                         }
1006                         qname = match_strdup(&args[0]);
1007                         if (!qname) {
1008                                 printk(KERN_ERR
1009                                         "EXT4-fs: not enough memory for "
1010                                         "storing quotafile name.\n");
1011                                 return 0;
1012                         }
1013                         if (sbi->s_qf_names[qtype] &&
1014                             strcmp(sbi->s_qf_names[qtype], qname)) {
1015                                 printk(KERN_ERR
1016                                         "EXT4-fs: %s quota file already "
1017                                         "specified.\n", QTYPE2NAME(qtype));
1018                                 kfree(qname);
1019                                 return 0;
1020                         }
1021                         sbi->s_qf_names[qtype] = qname;
1022                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1023                                 printk(KERN_ERR
1024                                         "EXT4-fs: quotafile must be on "
1025                                         "filesystem root.\n");
1026                                 kfree(sbi->s_qf_names[qtype]);
1027                                 sbi->s_qf_names[qtype] = NULL;
1028                                 return 0;
1029                         }
1030                         set_opt(sbi->s_mount_opt, QUOTA);
1031                         break;
1032                 case Opt_offusrjquota:
1033                         qtype = USRQUOTA;
1034                         goto clear_qf_name;
1035                 case Opt_offgrpjquota:
1036                         qtype = GRPQUOTA;
1037 clear_qf_name:
1038                         if (sb_any_quota_enabled(sb)) {
1039                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1040                                         "journalled quota options when "
1041                                         "quota turned on.\n");
1042                                 return 0;
1043                         }
1044                         /*
1045                          * The space will be released later when all options
1046                          * are confirmed to be correct
1047                          */
1048                         sbi->s_qf_names[qtype] = NULL;
1049                         break;
1050                 case Opt_jqfmt_vfsold:
1051                         sbi->s_jquota_fmt = QFMT_VFS_OLD;
1052                         break;
1053                 case Opt_jqfmt_vfsv0:
1054                         sbi->s_jquota_fmt = QFMT_VFS_V0;
1055                         break;
1056                 case Opt_quota:
1057                 case Opt_usrquota:
1058                         set_opt(sbi->s_mount_opt, QUOTA);
1059                         set_opt(sbi->s_mount_opt, USRQUOTA);
1060                         break;
1061                 case Opt_grpquota:
1062                         set_opt(sbi->s_mount_opt, QUOTA);
1063                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1064                         break;
1065                 case Opt_noquota:
1066                         if (sb_any_quota_enabled(sb)) {
1067                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1068                                         "options when quota turned on.\n");
1069                                 return 0;
1070                         }
1071                         clear_opt(sbi->s_mount_opt, QUOTA);
1072                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1073                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1074                         break;
1075 #else
1076                 case Opt_quota:
1077                 case Opt_usrquota:
1078                 case Opt_grpquota:
1079                 case Opt_usrjquota:
1080                 case Opt_grpjquota:
1081                 case Opt_offusrjquota:
1082                 case Opt_offgrpjquota:
1083                 case Opt_jqfmt_vfsold:
1084                 case Opt_jqfmt_vfsv0:
1085                         printk(KERN_ERR
1086                                 "EXT4-fs: journalled quota options not "
1087                                 "supported.\n");
1088                         break;
1089                 case Opt_noquota:
1090                         break;
1091 #endif
1092                 case Opt_abort:
1093                         set_opt(sbi->s_mount_opt, ABORT);
1094                         break;
1095                 case Opt_barrier:
1096                         if (match_int(&args[0], &option))
1097                                 return 0;
1098                         if (option)
1099                                 set_opt(sbi->s_mount_opt, BARRIER);
1100                         else
1101                                 clear_opt(sbi->s_mount_opt, BARRIER);
1102                         break;
1103                 case Opt_ignore:
1104                         break;
1105                 case Opt_resize:
1106                         if (!is_remount) {
1107                                 printk("EXT4-fs: resize option only available "
1108                                         "for remount\n");
1109                                 return 0;
1110                         }
1111                         if (match_int(&args[0], &option) != 0)
1112                                 return 0;
1113                         *n_blocks_count = option;
1114                         break;
1115                 case Opt_nobh:
1116                         set_opt(sbi->s_mount_opt, NOBH);
1117                         break;
1118                 case Opt_bh:
1119                         clear_opt(sbi->s_mount_opt, NOBH);
1120                         break;
1121                 case Opt_extents:
1122                         set_opt (sbi->s_mount_opt, EXTENTS);
1123                         break;
1124                 case Opt_noextents:
1125                         clear_opt (sbi->s_mount_opt, EXTENTS);
1126                         break;
1127                 default:
1128                         printk (KERN_ERR
1129                                 "EXT4-fs: Unrecognized mount option \"%s\" "
1130                                 "or missing value\n", p);
1131                         return 0;
1132                 }
1133         }
1134 #ifdef CONFIG_QUOTA
1135         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1136                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1137                      sbi->s_qf_names[USRQUOTA])
1138                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1139
1140                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1141                      sbi->s_qf_names[GRPQUOTA])
1142                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1143
1144                 if ((sbi->s_qf_names[USRQUOTA] &&
1145                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1146                     (sbi->s_qf_names[GRPQUOTA] &&
1147                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1148                         printk(KERN_ERR "EXT4-fs: old and new quota "
1149                                         "format mixing.\n");
1150                         return 0;
1151                 }
1152
1153                 if (!sbi->s_jquota_fmt) {
1154                         printk(KERN_ERR "EXT4-fs: journalled quota format "
1155                                         "not specified.\n");
1156                         return 0;
1157                 }
1158         } else {
1159                 if (sbi->s_jquota_fmt) {
1160                         printk(KERN_ERR "EXT4-fs: journalled quota format "
1161                                         "specified with no journalling "
1162                                         "enabled.\n");
1163                         return 0;
1164                 }
1165         }
1166 #endif
1167         return 1;
1168 }
1169
1170 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1171                             int read_only)
1172 {
1173         struct ext4_sb_info *sbi = EXT4_SB(sb);
1174         int res = 0;
1175
1176         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1177                 printk (KERN_ERR "EXT4-fs warning: revision level too high, "
1178                         "forcing read-only mode\n");
1179                 res = MS_RDONLY;
1180         }
1181         if (read_only)
1182                 return res;
1183         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1184                 printk (KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1185                         "running e2fsck is recommended\n");
1186         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1187                 printk (KERN_WARNING
1188                         "EXT4-fs warning: mounting fs with errors, "
1189                         "running e2fsck is recommended\n");
1190         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1191                  le16_to_cpu(es->s_mnt_count) >=
1192                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1193                 printk (KERN_WARNING
1194                         "EXT4-fs warning: maximal mount count reached, "
1195                         "running e2fsck is recommended\n");
1196         else if (le32_to_cpu(es->s_checkinterval) &&
1197                 (le32_to_cpu(es->s_lastcheck) +
1198                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1199                 printk (KERN_WARNING
1200                         "EXT4-fs warning: checktime reached, "
1201                         "running e2fsck is recommended\n");
1202 #if 0
1203                 /* @@@ We _will_ want to clear the valid bit if we find
1204                  * inconsistencies, to force a fsck at reboot.  But for
1205                  * a plain journaled filesystem we can keep it set as
1206                  * valid forever! :)
1207                  */
1208         es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT4_VALID_FS);
1209 #endif
1210         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1211                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1212         es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
1213         es->s_mtime = cpu_to_le32(get_seconds());
1214         ext4_update_dynamic_rev(sb);
1215         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1216
1217         ext4_commit_super(sb, es, 1);
1218         if (test_opt(sb, DEBUG))
1219                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1220                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1221                         sb->s_blocksize,
1222                         sbi->s_groups_count,
1223                         EXT4_BLOCKS_PER_GROUP(sb),
1224                         EXT4_INODES_PER_GROUP(sb),
1225                         sbi->s_mount_opt);
1226
1227         printk(KERN_INFO "EXT4 FS on %s, ", sb->s_id);
1228         if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
1229                 char b[BDEVNAME_SIZE];
1230
1231                 printk("external journal on %s\n",
1232                         bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
1233         } else {
1234                 printk("internal journal\n");
1235         }
1236         return res;
1237 }
1238
1239 /* Called at mount-time, super-block is locked */
1240 static int ext4_check_descriptors (struct super_block * sb)
1241 {
1242         struct ext4_sb_info *sbi = EXT4_SB(sb);
1243         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1244         ext4_fsblk_t last_block;
1245         ext4_fsblk_t block_bitmap;
1246         ext4_fsblk_t inode_bitmap;
1247         ext4_fsblk_t inode_table;
1248         struct ext4_group_desc * gdp = NULL;
1249         int desc_block = 0;
1250         int i;
1251
1252         ext4_debug ("Checking group descriptors");
1253
1254         for (i = 0; i < sbi->s_groups_count; i++)
1255         {
1256                 if (i == sbi->s_groups_count - 1)
1257                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1258                 else
1259                         last_block = first_block +
1260                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1261
1262                 if ((i % EXT4_DESC_PER_BLOCK(sb)) == 0)
1263                         gdp = (struct ext4_group_desc *)
1264                                         sbi->s_group_desc[desc_block++]->b_data;
1265                 block_bitmap = ext4_block_bitmap(sb, gdp);
1266                 if (block_bitmap < first_block || block_bitmap > last_block)
1267                 {
1268                         ext4_error (sb, "ext4_check_descriptors",
1269                                     "Block bitmap for group %d"
1270                                     " not in group (block %llu)!",
1271                                     i, block_bitmap);
1272                         return 0;
1273                 }
1274                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1275                 if (inode_bitmap < first_block || inode_bitmap > last_block)
1276                 {
1277                         ext4_error (sb, "ext4_check_descriptors",
1278                                     "Inode bitmap for group %d"
1279                                     " not in group (block %llu)!",
1280                                     i, inode_bitmap);
1281                         return 0;
1282                 }
1283                 inode_table = ext4_inode_table(sb, gdp);
1284                 if (inode_table < first_block ||
1285                     inode_table + sbi->s_itb_per_group > last_block)
1286                 {
1287                         ext4_error (sb, "ext4_check_descriptors",
1288                                     "Inode table for group %d"
1289                                     " not in group (block %llu)!",
1290                                     i, inode_table);
1291                         return 0;
1292                 }
1293                 first_block += EXT4_BLOCKS_PER_GROUP(sb);
1294                 gdp = (struct ext4_group_desc *)
1295                         ((__u8 *)gdp + EXT4_DESC_SIZE(sb));
1296         }
1297
1298         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1299         sbi->s_es->s_free_inodes_count=cpu_to_le32(ext4_count_free_inodes(sb));
1300         return 1;
1301 }
1302
1303
1304 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1305  * the superblock) which were deleted from all directories, but held open by
1306  * a process at the time of a crash.  We walk the list and try to delete these
1307  * inodes at recovery time (only with a read-write filesystem).
1308  *
1309  * In order to keep the orphan inode chain consistent during traversal (in
1310  * case of crash during recovery), we link each inode into the superblock
1311  * orphan list_head and handle it the same way as an inode deletion during
1312  * normal operation (which journals the operations for us).
1313  *
1314  * We only do an iget() and an iput() on each inode, which is very safe if we
1315  * accidentally point at an in-use or already deleted inode.  The worst that
1316  * can happen in this case is that we get a "bit already cleared" message from
1317  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1318  * e2fsck was run on this filesystem, and it must have already done the orphan
1319  * inode cleanup for us, so we can safely abort without any further action.
1320  */
1321 static void ext4_orphan_cleanup (struct super_block * sb,
1322                                  struct ext4_super_block * es)
1323 {
1324         unsigned int s_flags = sb->s_flags;
1325         int nr_orphans = 0, nr_truncates = 0;
1326 #ifdef CONFIG_QUOTA
1327         int i;
1328 #endif
1329         if (!es->s_last_orphan) {
1330                 jbd_debug(4, "no orphan inodes to clean up\n");
1331                 return;
1332         }
1333
1334         if (bdev_read_only(sb->s_bdev)) {
1335                 printk(KERN_ERR "EXT4-fs: write access "
1336                         "unavailable, skipping orphan cleanup.\n");
1337                 return;
1338         }
1339
1340         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1341                 if (es->s_last_orphan)
1342                         jbd_debug(1, "Errors on filesystem, "
1343                                   "clearing orphan list.\n");
1344                 es->s_last_orphan = 0;
1345                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1346                 return;
1347         }
1348
1349         if (s_flags & MS_RDONLY) {
1350                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1351                        sb->s_id);
1352                 sb->s_flags &= ~MS_RDONLY;
1353         }
1354 #ifdef CONFIG_QUOTA
1355         /* Needed for iput() to work correctly and not trash data */
1356         sb->s_flags |= MS_ACTIVE;
1357         /* Turn on quotas so that they are updated correctly */
1358         for (i = 0; i < MAXQUOTAS; i++) {
1359                 if (EXT4_SB(sb)->s_qf_names[i]) {
1360                         int ret = ext4_quota_on_mount(sb, i);
1361                         if (ret < 0)
1362                                 printk(KERN_ERR
1363                                         "EXT4-fs: Cannot turn on journalled "
1364                                         "quota: error %d\n", ret);
1365                 }
1366         }
1367 #endif
1368
1369         while (es->s_last_orphan) {
1370                 struct inode *inode;
1371
1372                 if (!(inode =
1373                       ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan)))) {
1374                         es->s_last_orphan = 0;
1375                         break;
1376                 }
1377
1378                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1379                 DQUOT_INIT(inode);
1380                 if (inode->i_nlink) {
1381                         printk(KERN_DEBUG
1382                                 "%s: truncating inode %lu to %Ld bytes\n",
1383                                 __FUNCTION__, inode->i_ino, inode->i_size);
1384                         jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
1385                                   inode->i_ino, inode->i_size);
1386                         ext4_truncate(inode);
1387                         nr_truncates++;
1388                 } else {
1389                         printk(KERN_DEBUG
1390                                 "%s: deleting unreferenced inode %lu\n",
1391                                 __FUNCTION__, inode->i_ino);
1392                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1393                                   inode->i_ino);
1394                         nr_orphans++;
1395                 }
1396                 iput(inode);  /* The delete magic happens here! */
1397         }
1398
1399 #define PLURAL(x) (x), ((x)==1) ? "" : "s"
1400
1401         if (nr_orphans)
1402                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1403                        sb->s_id, PLURAL(nr_orphans));
1404         if (nr_truncates)
1405                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1406                        sb->s_id, PLURAL(nr_truncates));
1407 #ifdef CONFIG_QUOTA
1408         /* Turn quotas off */
1409         for (i = 0; i < MAXQUOTAS; i++) {
1410                 if (sb_dqopt(sb)->files[i])
1411                         vfs_quota_off(sb, i);
1412         }
1413 #endif
1414         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1415 }
1416
1417 #define log2(n) ffz(~(n))
1418
1419 /*
1420  * Maximal file size.  There is a direct, and {,double-,triple-}indirect
1421  * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
1422  * We need to be 1 filesystem block less than the 2^32 sector limit.
1423  */
1424 static loff_t ext4_max_size(int bits)
1425 {
1426         loff_t res = EXT4_NDIR_BLOCKS;
1427         /* This constant is calculated to be the largest file size for a
1428          * dense, 4k-blocksize file such that the total number of
1429          * sectors in the file, including data and all indirect blocks,
1430          * does not exceed 2^32. */
1431         const loff_t upper_limit = 0x1ff7fffd000LL;
1432
1433         res += 1LL << (bits-2);
1434         res += 1LL << (2*(bits-2));
1435         res += 1LL << (3*(bits-2));
1436         res <<= bits;
1437         if (res > upper_limit)
1438                 res = upper_limit;
1439         return res;
1440 }
1441
1442 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1443                                 ext4_fsblk_t logical_sb_block, int nr)
1444 {
1445         struct ext4_sb_info *sbi = EXT4_SB(sb);
1446         unsigned long bg, first_meta_bg;
1447         int has_super = 0;
1448
1449         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1450
1451         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1452             nr < first_meta_bg)
1453                 return logical_sb_block + nr + 1;
1454         bg = sbi->s_desc_per_block * nr;
1455         if (ext4_bg_has_super(sb, bg))
1456                 has_super = 1;
1457         return (has_super + ext4_group_first_block_no(sb, bg));
1458 }
1459
1460
1461 static int ext4_fill_super (struct super_block *sb, void *data, int silent)
1462 {
1463         struct buffer_head * bh;
1464         struct ext4_super_block *es = NULL;
1465         struct ext4_sb_info *sbi;
1466         ext4_fsblk_t block;
1467         ext4_fsblk_t sb_block = get_sb_block(&data);
1468         ext4_fsblk_t logical_sb_block;
1469         unsigned long offset = 0;
1470         unsigned int journal_inum = 0;
1471         unsigned long journal_devnum = 0;
1472         unsigned long def_mount_opts;
1473         struct inode *root;
1474         int blocksize;
1475         int hblock;
1476         int db_count;
1477         int i;
1478         int needs_recovery;
1479         __le32 features;
1480         __u64 blocks_count;
1481
1482         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1483         if (!sbi)
1484                 return -ENOMEM;
1485         sb->s_fs_info = sbi;
1486         sbi->s_mount_opt = 0;
1487         sbi->s_resuid = EXT4_DEF_RESUID;
1488         sbi->s_resgid = EXT4_DEF_RESGID;
1489
1490         unlock_kernel();
1491
1492         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1493         if (!blocksize) {
1494                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1495                 goto out_fail;
1496         }
1497
1498         /*
1499          * The ext4 superblock will not be buffer aligned for other than 1kB
1500          * block sizes.  We need to calculate the offset from buffer start.
1501          */
1502         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1503                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1504                 offset = do_div(logical_sb_block, blocksize);
1505         } else {
1506                 logical_sb_block = sb_block;
1507         }
1508
1509         if (!(bh = sb_bread(sb, logical_sb_block))) {
1510                 printk (KERN_ERR "EXT4-fs: unable to read superblock\n");
1511                 goto out_fail;
1512         }
1513         /*
1514          * Note: s_es must be initialized as soon as possible because
1515          *       some ext4 macro-instructions depend on its value
1516          */
1517         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1518         sbi->s_es = es;
1519         sb->s_magic = le16_to_cpu(es->s_magic);
1520         if (sb->s_magic != EXT4_SUPER_MAGIC)
1521                 goto cantfind_ext4;
1522
1523         /* Set defaults before we parse the mount options */
1524         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1525         if (def_mount_opts & EXT4_DEFM_DEBUG)
1526                 set_opt(sbi->s_mount_opt, DEBUG);
1527         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1528                 set_opt(sbi->s_mount_opt, GRPID);
1529         if (def_mount_opts & EXT4_DEFM_UID16)
1530                 set_opt(sbi->s_mount_opt, NO_UID32);
1531 #ifdef CONFIG_EXT4DEV_FS_XATTR
1532         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1533                 set_opt(sbi->s_mount_opt, XATTR_USER);
1534 #endif
1535 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1536         if (def_mount_opts & EXT4_DEFM_ACL)
1537                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1538 #endif
1539         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1540                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1541         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1542                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1543         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1544                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
1545
1546         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
1547                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1548         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_RO)
1549                 set_opt(sbi->s_mount_opt, ERRORS_RO);
1550         else
1551                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
1552
1553         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
1554         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
1555
1556         set_opt(sbi->s_mount_opt, RESERVATION);
1557
1558         /*
1559          * turn on extents feature by default in ext4 filesystem
1560          * User -o noextents to turn it off
1561          */
1562         set_opt(sbi->s_mount_opt, EXTENTS);
1563
1564         if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
1565                             NULL, 0))
1566                 goto failed_mount;
1567
1568         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1569                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1570
1571         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
1572             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
1573              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
1574              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
1575                 printk(KERN_WARNING
1576                        "EXT4-fs warning: feature flags set on rev 0 fs, "
1577                        "running e2fsck is recommended\n");
1578         /*
1579          * Check feature flags regardless of the revision level, since we
1580          * previously didn't change the revision level when setting the flags,
1581          * so there is a chance incompat flags are set on a rev 0 filesystem.
1582          */
1583         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
1584         if (features) {
1585                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
1586                        "unsupported optional features (%x).\n",
1587                        sb->s_id, le32_to_cpu(features));
1588                 goto failed_mount;
1589         }
1590         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
1591         if (!(sb->s_flags & MS_RDONLY) && features) {
1592                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
1593                        "unsupported optional features (%x).\n",
1594                        sb->s_id, le32_to_cpu(features));
1595                 goto failed_mount;
1596         }
1597         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
1598
1599         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
1600             blocksize > EXT4_MAX_BLOCK_SIZE) {
1601                 printk(KERN_ERR
1602                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
1603                        blocksize, sb->s_id);
1604                 goto failed_mount;
1605         }
1606
1607         hblock = bdev_hardsect_size(sb->s_bdev);
1608         if (sb->s_blocksize != blocksize) {
1609                 /*
1610                  * Make sure the blocksize for the filesystem is larger
1611                  * than the hardware sectorsize for the machine.
1612                  */
1613                 if (blocksize < hblock) {
1614                         printk(KERN_ERR "EXT4-fs: blocksize %d too small for "
1615                                "device blocksize %d.\n", blocksize, hblock);
1616                         goto failed_mount;
1617                 }
1618
1619                 brelse (bh);
1620                 sb_set_blocksize(sb, blocksize);
1621                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1622                 offset = do_div(logical_sb_block, blocksize);
1623                 bh = sb_bread(sb, logical_sb_block);
1624                 if (!bh) {
1625                         printk(KERN_ERR
1626                                "EXT4-fs: Can't read superblock on 2nd try.\n");
1627                         goto failed_mount;
1628                 }
1629                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
1630                 sbi->s_es = es;
1631                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
1632                         printk (KERN_ERR
1633                                 "EXT4-fs: Magic mismatch, very weird !\n");
1634                         goto failed_mount;
1635                 }
1636         }
1637
1638         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
1639
1640         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
1641                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
1642                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
1643         } else {
1644                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1645                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1646                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
1647                     (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
1648                     (sbi->s_inode_size > blocksize)) {
1649                         printk (KERN_ERR
1650                                 "EXT4-fs: unsupported inode size: %d\n",
1651                                 sbi->s_inode_size);
1652                         goto failed_mount;
1653                 }
1654                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
1655                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
1656         }
1657         sbi->s_frag_size = EXT4_MIN_FRAG_SIZE <<
1658                                    le32_to_cpu(es->s_log_frag_size);
1659         if (blocksize != sbi->s_frag_size) {
1660                 printk(KERN_ERR
1661                        "EXT4-fs: fragsize %lu != blocksize %u (unsupported)\n",
1662                        sbi->s_frag_size, blocksize);
1663                 goto failed_mount;
1664         }
1665         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
1666         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
1667                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
1668                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
1669                     sbi->s_desc_size & (sbi->s_desc_size - 1)) {
1670                         printk(KERN_ERR
1671                                "EXT4-fs: unsupported descriptor size %lu\n",
1672                                sbi->s_desc_size);
1673                         goto failed_mount;
1674                 }
1675         } else
1676                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
1677         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1678         sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1679         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1680         if (EXT4_INODE_SIZE(sb) == 0)
1681                 goto cantfind_ext4;
1682         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
1683         if (sbi->s_inodes_per_block == 0)
1684                 goto cantfind_ext4;
1685         sbi->s_itb_per_group = sbi->s_inodes_per_group /
1686                                         sbi->s_inodes_per_block;
1687         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
1688         sbi->s_sbh = bh;
1689         sbi->s_mount_state = le16_to_cpu(es->s_state);
1690         sbi->s_addr_per_block_bits = log2(EXT4_ADDR_PER_BLOCK(sb));
1691         sbi->s_desc_per_block_bits = log2(EXT4_DESC_PER_BLOCK(sb));
1692         for (i=0; i < 4; i++)
1693                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
1694         sbi->s_def_hash_version = es->s_def_hash_version;
1695
1696         if (sbi->s_blocks_per_group > blocksize * 8) {
1697                 printk (KERN_ERR
1698                         "EXT4-fs: #blocks per group too big: %lu\n",
1699                         sbi->s_blocks_per_group);
1700                 goto failed_mount;
1701         }
1702         if (sbi->s_frags_per_group > blocksize * 8) {
1703                 printk (KERN_ERR
1704                         "EXT4-fs: #fragments per group too big: %lu\n",
1705                         sbi->s_frags_per_group);
1706                 goto failed_mount;
1707         }
1708         if (sbi->s_inodes_per_group > blocksize * 8) {
1709                 printk (KERN_ERR
1710                         "EXT4-fs: #inodes per group too big: %lu\n",
1711                         sbi->s_inodes_per_group);
1712                 goto failed_mount;
1713         }
1714
1715         if (ext4_blocks_count(es) >
1716                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
1717                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
1718                         " too large to mount safely\n", sb->s_id);
1719                 if (sizeof(sector_t) < 8)
1720                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
1721                                         "enabled\n");
1722                 goto failed_mount;
1723         }
1724
1725         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
1726                 goto cantfind_ext4;
1727         blocks_count = (ext4_blocks_count(es) -
1728                         le32_to_cpu(es->s_first_data_block) +
1729                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
1730         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
1731         sbi->s_groups_count = blocks_count;
1732         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
1733                    EXT4_DESC_PER_BLOCK(sb);
1734         sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
1735                                     GFP_KERNEL);
1736         if (sbi->s_group_desc == NULL) {
1737                 printk (KERN_ERR "EXT4-fs: not enough memory\n");
1738                 goto failed_mount;
1739         }
1740
1741         bgl_lock_init(&sbi->s_blockgroup_lock);
1742
1743         for (i = 0; i < db_count; i++) {
1744                 block = descriptor_loc(sb, logical_sb_block, i);
1745                 sbi->s_group_desc[i] = sb_bread(sb, block);
1746                 if (!sbi->s_group_desc[i]) {
1747                         printk (KERN_ERR "EXT4-fs: "
1748                                 "can't read group descriptor %d\n", i);
1749                         db_count = i;
1750                         goto failed_mount2;
1751                 }
1752         }
1753         if (!ext4_check_descriptors (sb)) {
1754                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
1755                 goto failed_mount2;
1756         }
1757         sbi->s_gdb_count = db_count;
1758         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1759         spin_lock_init(&sbi->s_next_gen_lock);
1760
1761         percpu_counter_init(&sbi->s_freeblocks_counter,
1762                 ext4_count_free_blocks(sb));
1763         percpu_counter_init(&sbi->s_freeinodes_counter,
1764                 ext4_count_free_inodes(sb));
1765         percpu_counter_init(&sbi->s_dirs_counter,
1766                 ext4_count_dirs(sb));
1767
1768         /* per fileystem reservation list head & lock */
1769         spin_lock_init(&sbi->s_rsv_window_lock);
1770         sbi->s_rsv_window_root = RB_ROOT;
1771         /* Add a single, static dummy reservation to the start of the
1772          * reservation window list --- it gives us a placeholder for
1773          * append-at-start-of-list which makes the allocation logic
1774          * _much_ simpler. */
1775         sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
1776         sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
1777         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1778         sbi->s_rsv_window_head.rsv_goal_size = 0;
1779         ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
1780
1781         /*
1782          * set up enough so that it can read an inode
1783          */
1784         sb->s_op = &ext4_sops;
1785         sb->s_export_op = &ext4_export_ops;
1786         sb->s_xattr = ext4_xattr_handlers;
1787 #ifdef CONFIG_QUOTA
1788         sb->s_qcop = &ext4_qctl_operations;
1789         sb->dq_op = &ext4_quota_operations;
1790 #endif
1791         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
1792
1793         sb->s_root = NULL;
1794
1795         needs_recovery = (es->s_last_orphan != 0 ||
1796                           EXT4_HAS_INCOMPAT_FEATURE(sb,
1797                                     EXT4_FEATURE_INCOMPAT_RECOVER));
1798
1799         /*
1800          * The first inode we look at is the journal inode.  Don't try
1801          * root first: it may be modified in the journal!
1802          */
1803         if (!test_opt(sb, NOLOAD) &&
1804             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
1805                 if (ext4_load_journal(sb, es, journal_devnum))
1806                         goto failed_mount3;
1807         } else if (journal_inum) {
1808                 if (ext4_create_journal(sb, es, journal_inum))
1809                         goto failed_mount3;
1810         } else {
1811                 if (!silent)
1812                         printk (KERN_ERR
1813                                 "ext4: No journal on filesystem on %s\n",
1814                                 sb->s_id);
1815                 goto failed_mount3;
1816         }
1817
1818         if (ext4_blocks_count(es) > 0xffffffffULL &&
1819             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
1820                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
1821                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
1822                 goto failed_mount4;
1823         }
1824
1825         /* We have now updated the journal if required, so we can
1826          * validate the data journaling mode. */
1827         switch (test_opt(sb, DATA_FLAGS)) {
1828         case 0:
1829                 /* No mode set, assume a default based on the journal
1830                  * capabilities: ORDERED_DATA if the journal can
1831                  * cope, else JOURNAL_DATA
1832                  */
1833                 if (jbd2_journal_check_available_features
1834                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
1835                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
1836                 else
1837                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
1838                 break;
1839
1840         case EXT4_MOUNT_ORDERED_DATA:
1841         case EXT4_MOUNT_WRITEBACK_DATA:
1842                 if (!jbd2_journal_check_available_features
1843                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
1844                         printk(KERN_ERR "EXT4-fs: Journal does not support "
1845                                "requested data journaling mode\n");
1846                         goto failed_mount4;
1847                 }
1848         default:
1849                 break;
1850         }
1851
1852         if (test_opt(sb, NOBH)) {
1853                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
1854                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
1855                                 "its supported only with writeback mode\n");
1856                         clear_opt(sbi->s_mount_opt, NOBH);
1857                 }
1858         }
1859         /*
1860          * The jbd2_journal_load will have done any necessary log recovery,
1861          * so we can safely mount the rest of the filesystem now.
1862          */
1863
1864         root = iget(sb, EXT4_ROOT_INO);
1865         sb->s_root = d_alloc_root(root);
1866         if (!sb->s_root) {
1867                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
1868                 iput(root);
1869                 goto failed_mount4;
1870         }
1871         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1872                 dput(sb->s_root);
1873                 sb->s_root = NULL;
1874                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
1875                 goto failed_mount4;
1876         }
1877
1878         ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY);
1879
1880         /* determine the minimum size of new large inodes, if present */
1881         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
1882                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
1883                                                      EXT4_GOOD_OLD_INODE_SIZE;
1884                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1885                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
1886                         if (sbi->s_want_extra_isize <
1887                             le16_to_cpu(es->s_want_extra_isize))
1888                                 sbi->s_want_extra_isize =
1889                                         le16_to_cpu(es->s_want_extra_isize);
1890                         if (sbi->s_want_extra_isize <
1891                             le16_to_cpu(es->s_min_extra_isize))
1892                                 sbi->s_want_extra_isize =
1893                                         le16_to_cpu(es->s_min_extra_isize);
1894                 }
1895         }
1896         /* Check if enough inode space is available */
1897         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
1898                                                         sbi->s_inode_size) {
1899                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
1900                                                        EXT4_GOOD_OLD_INODE_SIZE;
1901                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
1902                         "available.\n");
1903         }
1904
1905         /*
1906          * akpm: core read_super() calls in here with the superblock locked.
1907          * That deadlocks, because orphan cleanup needs to lock the superblock
1908          * in numerous places.  Here we just pop the lock - it's relatively
1909          * harmless, because we are now ready to accept write_super() requests,
1910          * and aviro says that's the only reason for hanging onto the
1911          * superblock lock.
1912          */
1913         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
1914         ext4_orphan_cleanup(sb, es);
1915         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
1916         if (needs_recovery)
1917                 printk (KERN_INFO "EXT4-fs: recovery complete.\n");
1918         ext4_mark_recovery_complete(sb, es);
1919         printk (KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
1920                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
1921                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
1922                 "writeback");
1923
1924         ext4_ext_init(sb);
1925
1926         lock_kernel();
1927         return 0;
1928
1929 cantfind_ext4:
1930         if (!silent)
1931                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
1932                        sb->s_id);
1933         goto failed_mount;
1934
1935 failed_mount4:
1936         jbd2_journal_destroy(sbi->s_journal);
1937 failed_mount3:
1938         percpu_counter_destroy(&sbi->s_freeblocks_counter);
1939         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1940         percpu_counter_destroy(&sbi->s_dirs_counter);
1941 failed_mount2:
1942         for (i = 0; i < db_count; i++)
1943                 brelse(sbi->s_group_desc[i]);
1944         kfree(sbi->s_group_desc);
1945 failed_mount:
1946 #ifdef CONFIG_QUOTA
1947         for (i = 0; i < MAXQUOTAS; i++)
1948                 kfree(sbi->s_qf_names[i]);
1949 #endif
1950         ext4_blkdev_remove(sbi);
1951         brelse(bh);
1952 out_fail:
1953         sb->s_fs_info = NULL;
1954         kfree(sbi);
1955         lock_kernel();
1956         return -EINVAL;
1957 }
1958
1959 /*
1960  * Setup any per-fs journal parameters now.  We'll do this both on
1961  * initial mount, once the journal has been initialised but before we've
1962  * done any recovery; and again on any subsequent remount.
1963  */
1964 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
1965 {
1966         struct ext4_sb_info *sbi = EXT4_SB(sb);
1967
1968         if (sbi->s_commit_interval)
1969                 journal->j_commit_interval = sbi->s_commit_interval;
1970         /* We could also set up an ext4-specific default for the commit
1971          * interval here, but for now we'll just fall back to the jbd
1972          * default. */
1973
1974         spin_lock(&journal->j_state_lock);
1975         if (test_opt(sb, BARRIER))
1976                 journal->j_flags |= JBD2_BARRIER;
1977         else
1978                 journal->j_flags &= ~JBD2_BARRIER;
1979         spin_unlock(&journal->j_state_lock);
1980 }
1981
1982 static journal_t *ext4_get_journal(struct super_block *sb,
1983                                    unsigned int journal_inum)
1984 {
1985         struct inode *journal_inode;
1986         journal_t *journal;
1987
1988         /* First, test for the existence of a valid inode on disk.  Bad
1989          * things happen if we iget() an unused inode, as the subsequent
1990          * iput() will try to delete it. */
1991
1992         journal_inode = iget(sb, journal_inum);
1993         if (!journal_inode) {
1994                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
1995                 return NULL;
1996         }
1997         if (!journal_inode->i_nlink) {
1998                 make_bad_inode(journal_inode);
1999                 iput(journal_inode);
2000                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2001                 return NULL;
2002         }
2003
2004         jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
2005                   journal_inode, journal_inode->i_size);
2006         if (is_bad_inode(journal_inode) || !S_ISREG(journal_inode->i_mode)) {
2007                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2008                 iput(journal_inode);
2009                 return NULL;
2010         }
2011
2012         journal = jbd2_journal_init_inode(journal_inode);
2013         if (!journal) {
2014                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2015                 iput(journal_inode);
2016                 return NULL;
2017         }
2018         journal->j_private = sb;
2019         ext4_init_journal_params(sb, journal);
2020         return journal;
2021 }
2022
2023 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2024                                        dev_t j_dev)
2025 {
2026         struct buffer_head * bh;
2027         journal_t *journal;
2028         ext4_fsblk_t start;
2029         ext4_fsblk_t len;
2030         int hblock, blocksize;
2031         ext4_fsblk_t sb_block;
2032         unsigned long offset;
2033         struct ext4_super_block * es;
2034         struct block_device *bdev;
2035
2036         bdev = ext4_blkdev_get(j_dev);
2037         if (bdev == NULL)
2038                 return NULL;
2039
2040         if (bd_claim(bdev, sb)) {
2041                 printk(KERN_ERR
2042                         "EXT4: failed to claim external journal device.\n");
2043                 blkdev_put(bdev);
2044                 return NULL;
2045         }
2046
2047         blocksize = sb->s_blocksize;
2048         hblock = bdev_hardsect_size(bdev);
2049         if (blocksize < hblock) {
2050                 printk(KERN_ERR
2051                         "EXT4-fs: blocksize too small for journal device.\n");
2052                 goto out_bdev;
2053         }
2054
2055         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2056         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2057         set_blocksize(bdev, blocksize);
2058         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2059                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2060                        "external journal\n");
2061                 goto out_bdev;
2062         }
2063
2064         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2065         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2066             !(le32_to_cpu(es->s_feature_incompat) &
2067               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2068                 printk(KERN_ERR "EXT4-fs: external journal has "
2069                                         "bad superblock\n");
2070                 brelse(bh);
2071                 goto out_bdev;
2072         }
2073
2074         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2075                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2076                 brelse(bh);
2077                 goto out_bdev;
2078         }
2079
2080         len = ext4_blocks_count(es);
2081         start = sb_block + 1;
2082         brelse(bh);     /* we're done with the superblock */
2083
2084         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2085                                         start, len, blocksize);
2086         if (!journal) {
2087                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2088                 goto out_bdev;
2089         }
2090         journal->j_private = sb;
2091         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2092         wait_on_buffer(journal->j_sb_buffer);
2093         if (!buffer_uptodate(journal->j_sb_buffer)) {
2094                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2095                 goto out_journal;
2096         }
2097         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2098                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2099                                         "user (unsupported) - %d\n",
2100                         be32_to_cpu(journal->j_superblock->s_nr_users));
2101                 goto out_journal;
2102         }
2103         EXT4_SB(sb)->journal_bdev = bdev;
2104         ext4_init_journal_params(sb, journal);
2105         return journal;
2106 out_journal:
2107         jbd2_journal_destroy(journal);
2108 out_bdev:
2109         ext4_blkdev_put(bdev);
2110         return NULL;
2111 }
2112
2113 static int ext4_load_journal(struct super_block *sb,
2114                              struct ext4_super_block *es,
2115                              unsigned long journal_devnum)
2116 {
2117         journal_t *journal;
2118         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2119         dev_t journal_dev;
2120         int err = 0;
2121         int really_read_only;
2122
2123         if (journal_devnum &&
2124             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2125                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2126                         "numbers have changed\n");
2127                 journal_dev = new_decode_dev(journal_devnum);
2128         } else
2129                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2130
2131         really_read_only = bdev_read_only(sb->s_bdev);
2132
2133         /*
2134          * Are we loading a blank journal or performing recovery after a
2135          * crash?  For recovery, we need to check in advance whether we
2136          * can get read-write access to the device.
2137          */
2138
2139         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2140                 if (sb->s_flags & MS_RDONLY) {
2141                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2142                                         "required on readonly filesystem.\n");
2143                         if (really_read_only) {
2144                                 printk(KERN_ERR "EXT4-fs: write access "
2145                                         "unavailable, cannot proceed.\n");
2146                                 return -EROFS;
2147                         }
2148                         printk (KERN_INFO "EXT4-fs: write access will "
2149                                         "be enabled during recovery.\n");
2150                 }
2151         }
2152
2153         if (journal_inum && journal_dev) {
2154                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2155                        "and inode journals!\n");
2156                 return -EINVAL;
2157         }
2158
2159         if (journal_inum) {
2160                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2161                         return -EINVAL;
2162         } else {
2163                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2164                         return -EINVAL;
2165         }
2166
2167         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2168                 err = jbd2_journal_update_format(journal);
2169                 if (err)  {
2170                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2171                         jbd2_journal_destroy(journal);
2172                         return err;
2173                 }
2174         }
2175
2176         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2177                 err = jbd2_journal_wipe(journal, !really_read_only);
2178         if (!err)
2179                 err = jbd2_journal_load(journal);
2180
2181         if (err) {
2182                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2183                 jbd2_journal_destroy(journal);
2184                 return err;
2185         }
2186
2187         EXT4_SB(sb)->s_journal = journal;
2188         ext4_clear_journal_err(sb, es);
2189
2190         if (journal_devnum &&
2191             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2192                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2193                 sb->s_dirt = 1;
2194
2195                 /* Make sure we flush the recovery flag to disk. */
2196                 ext4_commit_super(sb, es, 1);
2197         }
2198
2199         return 0;
2200 }
2201
2202 static int ext4_create_journal(struct super_block * sb,
2203                                struct ext4_super_block * es,
2204                                unsigned int journal_inum)
2205 {
2206         journal_t *journal;
2207         int err;
2208
2209         if (sb->s_flags & MS_RDONLY) {
2210                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2211                                 "create journal.\n");
2212                 return -EROFS;
2213         }
2214
2215         journal = ext4_get_journal(sb, journal_inum);
2216         if (!journal)
2217                 return -EINVAL;
2218
2219         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2220                journal_inum);
2221
2222         err = jbd2_journal_create(journal);
2223         if (err) {
2224                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2225                 jbd2_journal_destroy(journal);
2226                 return -EIO;
2227         }
2228
2229         EXT4_SB(sb)->s_journal = journal;
2230
2231         ext4_update_dynamic_rev(sb);
2232         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2233         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2234
2235         es->s_journal_inum = cpu_to_le32(journal_inum);
2236         sb->s_dirt = 1;
2237
2238         /* Make sure we flush the recovery flag to disk. */
2239         ext4_commit_super(sb, es, 1);
2240
2241         return 0;
2242 }
2243
2244 static void ext4_commit_super (struct super_block * sb,
2245                                struct ext4_super_block * es,
2246                                int sync)
2247 {
2248         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2249
2250         if (!sbh)
2251                 return;
2252         es->s_wtime = cpu_to_le32(get_seconds());
2253         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2254         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2255         BUFFER_TRACE(sbh, "marking dirty");
2256         mark_buffer_dirty(sbh);
2257         if (sync)
2258                 sync_dirty_buffer(sbh);
2259 }
2260
2261
2262 /*
2263  * Have we just finished recovery?  If so, and if we are mounting (or
2264  * remounting) the filesystem readonly, then we will end up with a
2265  * consistent fs on disk.  Record that fact.
2266  */
2267 static void ext4_mark_recovery_complete(struct super_block * sb,
2268                                         struct ext4_super_block * es)
2269 {
2270         journal_t *journal = EXT4_SB(sb)->s_journal;
2271
2272         jbd2_journal_lock_updates(journal);
2273         jbd2_journal_flush(journal);
2274         lock_super(sb);
2275         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2276             sb->s_flags & MS_RDONLY) {
2277                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2278                 sb->s_dirt = 0;
2279                 ext4_commit_super(sb, es, 1);
2280         }
2281         unlock_super(sb);
2282         jbd2_journal_unlock_updates(journal);
2283 }
2284
2285 /*
2286  * If we are mounting (or read-write remounting) a filesystem whose journal
2287  * has recorded an error from a previous lifetime, move that error to the
2288  * main filesystem now.
2289  */
2290 static void ext4_clear_journal_err(struct super_block * sb,
2291                                    struct ext4_super_block * es)
2292 {
2293         journal_t *journal;
2294         int j_errno;
2295         const char *errstr;
2296
2297         journal = EXT4_SB(sb)->s_journal;
2298
2299         /*
2300          * Now check for any error status which may have been recorded in the
2301          * journal by a prior ext4_error() or ext4_abort()
2302          */
2303
2304         j_errno = jbd2_journal_errno(journal);
2305         if (j_errno) {
2306                 char nbuf[16];
2307
2308                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2309                 ext4_warning(sb, __FUNCTION__, "Filesystem error recorded "
2310                              "from previous mount: %s", errstr);
2311                 ext4_warning(sb, __FUNCTION__, "Marking fs in need of "
2312                              "filesystem check.");
2313
2314                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2315                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2316                 ext4_commit_super (sb, es, 1);
2317
2318                 jbd2_journal_clear_err(journal);
2319         }
2320 }
2321
2322 /*
2323  * Force the running and committing transactions to commit,
2324  * and wait on the commit.
2325  */
2326 int ext4_force_commit(struct super_block *sb)
2327 {
2328         journal_t *journal;
2329         int ret;
2330
2331         if (sb->s_flags & MS_RDONLY)
2332                 return 0;
2333
2334         journal = EXT4_SB(sb)->s_journal;
2335         sb->s_dirt = 0;
2336         ret = ext4_journal_force_commit(journal);
2337         return ret;
2338 }
2339
2340 /*
2341  * Ext4 always journals updates to the superblock itself, so we don't
2342  * have to propagate any other updates to the superblock on disk at this
2343  * point.  Just start an async writeback to get the buffers on their way
2344  * to the disk.
2345  *
2346  * This implicitly triggers the writebehind on sync().
2347  */
2348
2349 static void ext4_write_super (struct super_block * sb)
2350 {
2351         if (mutex_trylock(&sb->s_lock) != 0)
2352                 BUG();
2353         sb->s_dirt = 0;
2354 }
2355
2356 static int ext4_sync_fs(struct super_block *sb, int wait)
2357 {
2358         tid_t target;
2359
2360         sb->s_dirt = 0;
2361         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2362                 if (wait)
2363                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2364         }
2365         return 0;
2366 }
2367
2368 /*
2369  * LVM calls this function before a (read-only) snapshot is created.  This
2370  * gives us a chance to flush the journal completely and mark the fs clean.
2371  */
2372 static void ext4_write_super_lockfs(struct super_block *sb)
2373 {
2374         sb->s_dirt = 0;
2375
2376         if (!(sb->s_flags & MS_RDONLY)) {
2377                 journal_t *journal = EXT4_SB(sb)->s_journal;
2378
2379                 /* Now we set up the journal barrier. */
2380                 jbd2_journal_lock_updates(journal);
2381                 jbd2_journal_flush(journal);
2382
2383                 /* Journal blocked and flushed, clear needs_recovery flag. */
2384                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2385                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2386         }
2387 }
2388
2389 /*
2390  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2391  * flag here, even though the filesystem is not technically dirty yet.
2392  */
2393 static void ext4_unlockfs(struct super_block *sb)
2394 {
2395         if (!(sb->s_flags & MS_RDONLY)) {
2396                 lock_super(sb);
2397                 /* Reser the needs_recovery flag before the fs is unlocked. */
2398                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2399                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2400                 unlock_super(sb);
2401                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2402         }
2403 }
2404
2405 static int ext4_remount (struct super_block * sb, int * flags, char * data)
2406 {
2407         struct ext4_super_block * es;
2408         struct ext4_sb_info *sbi = EXT4_SB(sb);
2409         ext4_fsblk_t n_blocks_count = 0;
2410         unsigned long old_sb_flags;
2411         struct ext4_mount_options old_opts;
2412         int err;
2413 #ifdef CONFIG_QUOTA
2414         int i;
2415 #endif
2416
2417         /* Store the original options */
2418         old_sb_flags = sb->s_flags;
2419         old_opts.s_mount_opt = sbi->s_mount_opt;
2420         old_opts.s_resuid = sbi->s_resuid;
2421         old_opts.s_resgid = sbi->s_resgid;
2422         old_opts.s_commit_interval = sbi->s_commit_interval;
2423 #ifdef CONFIG_QUOTA
2424         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
2425         for (i = 0; i < MAXQUOTAS; i++)
2426                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
2427 #endif
2428
2429         /*
2430          * Allow the "check" option to be passed as a remount option.
2431          */
2432         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
2433                 err = -EINVAL;
2434                 goto restore_opts;
2435         }
2436
2437         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
2438                 ext4_abort(sb, __FUNCTION__, "Abort forced by user");
2439
2440         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2441                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2442
2443         es = sbi->s_es;
2444
2445         ext4_init_journal_params(sb, sbi->s_journal);
2446
2447         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
2448                 n_blocks_count > ext4_blocks_count(es)) {
2449                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
2450                         err = -EROFS;
2451                         goto restore_opts;
2452                 }
2453
2454                 if (*flags & MS_RDONLY) {
2455                         /*
2456                          * First of all, the unconditional stuff we have to do
2457                          * to disable replay of the journal when we next remount
2458                          */
2459                         sb->s_flags |= MS_RDONLY;
2460
2461                         /*
2462                          * OK, test if we are remounting a valid rw partition
2463                          * readonly, and if so set the rdonly flag and then
2464                          * mark the partition as valid again.
2465                          */
2466                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
2467                             (sbi->s_mount_state & EXT4_VALID_FS))
2468                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
2469
2470                         /*
2471                          * We have to unlock super so that we can wait for
2472                          * transactions.
2473                          */
2474                         unlock_super(sb);
2475                         ext4_mark_recovery_complete(sb, es);
2476                         lock_super(sb);
2477                 } else {
2478                         __le32 ret;
2479                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2480                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
2481                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
2482                                        "remount RDWR because of unsupported "
2483                                        "optional features (%x).\n",
2484                                        sb->s_id, le32_to_cpu(ret));
2485                                 err = -EROFS;
2486                                 goto restore_opts;
2487                         }
2488
2489                         /*
2490                          * If we have an unprocessed orphan list hanging
2491                          * around from a previously readonly bdev mount,
2492                          * require a full umount/remount for now.
2493                          */
2494                         if (es->s_last_orphan) {
2495                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
2496                                        "remount RDWR because of unprocessed "
2497                                        "orphan inode list.  Please "
2498                                        "umount/remount instead.\n",
2499                                        sb->s_id);
2500                                 err = -EINVAL;
2501                                 goto restore_opts;
2502                         }
2503
2504                         /*
2505                          * Mounting a RDONLY partition read-write, so reread
2506                          * and store the current valid flag.  (It may have
2507                          * been changed by e2fsck since we originally mounted
2508                          * the partition.)
2509                          */
2510                         ext4_clear_journal_err(sb, es);
2511                         sbi->s_mount_state = le16_to_cpu(es->s_state);
2512                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
2513                                 goto restore_opts;
2514                         if (!ext4_setup_super (sb, es, 0))
2515                                 sb->s_flags &= ~MS_RDONLY;
2516                 }
2517         }
2518 #ifdef CONFIG_QUOTA
2519         /* Release old quota file names */
2520         for (i = 0; i < MAXQUOTAS; i++)
2521                 if (old_opts.s_qf_names[i] &&
2522                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
2523                         kfree(old_opts.s_qf_names[i]);
2524 #endif
2525         return 0;
2526 restore_opts:
2527         sb->s_flags = old_sb_flags;
2528         sbi->s_mount_opt = old_opts.s_mount_opt;
2529         sbi->s_resuid = old_opts.s_resuid;
2530         sbi->s_resgid = old_opts.s_resgid;
2531         sbi->s_commit_interval = old_opts.s_commit_interval;
2532 #ifdef CONFIG_QUOTA
2533         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
2534         for (i = 0; i < MAXQUOTAS; i++) {
2535                 if (sbi->s_qf_names[i] &&
2536                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
2537                         kfree(sbi->s_qf_names[i]);
2538                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
2539         }
2540 #endif
2541         return err;
2542 }
2543
2544 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
2545 {
2546         struct super_block *sb = dentry->d_sb;
2547         struct ext4_sb_info *sbi = EXT4_SB(sb);
2548         struct ext4_super_block *es = sbi->s_es;
2549         u64 fsid;
2550
2551         if (test_opt(sb, MINIX_DF)) {
2552                 sbi->s_overhead_last = 0;
2553         } else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
2554                 unsigned long ngroups = sbi->s_groups_count, i;
2555                 ext4_fsblk_t overhead = 0;
2556                 smp_rmb();
2557
2558                 /*
2559                  * Compute the overhead (FS structures).  This is constant
2560                  * for a given filesystem unless the number of block groups
2561                  * changes so we cache the previous value until it does.
2562                  */
2563
2564                 /*
2565                  * All of the blocks before first_data_block are
2566                  * overhead
2567                  */
2568                 overhead = le32_to_cpu(es->s_first_data_block);
2569
2570                 /*
2571                  * Add the overhead attributed to the superblock and
2572                  * block group descriptors.  If the sparse superblocks
2573                  * feature is turned on, then not all groups have this.
2574                  */
2575                 for (i = 0; i < ngroups; i++) {
2576                         overhead += ext4_bg_has_super(sb, i) +
2577                                 ext4_bg_num_gdb(sb, i);
2578                         cond_resched();
2579                 }
2580
2581                 /*
2582                  * Every block group has an inode bitmap, a block
2583                  * bitmap, and an inode table.
2584                  */
2585                 overhead += ngroups * (2 + sbi->s_itb_per_group);
2586                 sbi->s_overhead_last = overhead;
2587                 smp_wmb();
2588                 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
2589         }
2590
2591         buf->f_type = EXT4_SUPER_MAGIC;
2592         buf->f_bsize = sb->s_blocksize;
2593         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
2594         buf->f_bfree = percpu_counter_sum(&sbi->s_freeblocks_counter);
2595         es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
2596         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
2597         if (buf->f_bfree < ext4_r_blocks_count(es))
2598                 buf->f_bavail = 0;
2599         buf->f_files = le32_to_cpu(es->s_inodes_count);
2600         buf->f_ffree = percpu_counter_sum(&sbi->s_freeinodes_counter);
2601         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
2602         buf->f_namelen = EXT4_NAME_LEN;
2603         fsid = le64_to_cpup((void *)es->s_uuid) ^
2604                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
2605         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
2606         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
2607         return 0;
2608 }
2609
2610 /* Helper function for writing quotas on sync - we need to start transaction before quota file
2611  * is locked for write. Otherwise the are possible deadlocks:
2612  * Process 1                         Process 2
2613  * ext4_create()                     quota_sync()
2614  *   jbd2_journal_start()                   write_dquot()
2615  *   DQUOT_INIT()                        down(dqio_mutex)
2616  *     down(dqio_mutex)                    jbd2_journal_start()
2617  *
2618  */
2619
2620 #ifdef CONFIG_QUOTA
2621
2622 static inline struct inode *dquot_to_inode(struct dquot *dquot)
2623 {
2624         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
2625 }
2626
2627 static int ext4_dquot_initialize(struct inode *inode, int type)
2628 {
2629         handle_t *handle;
2630         int ret, err;
2631
2632         /* We may create quota structure so we need to reserve enough blocks */
2633         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
2634         if (IS_ERR(handle))
2635                 return PTR_ERR(handle);
2636         ret = dquot_initialize(inode, type);
2637         err = ext4_journal_stop(handle);
2638         if (!ret)
2639                 ret = err;
2640         return ret;
2641 }
2642
2643 static int ext4_dquot_drop(struct inode *inode)
2644 {
2645         handle_t *handle;
2646         int ret, err;
2647
2648         /* We may delete quota structure so we need to reserve enough blocks */
2649         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
2650         if (IS_ERR(handle))
2651                 return PTR_ERR(handle);
2652         ret = dquot_drop(inode);
2653         err = ext4_journal_stop(handle);
2654         if (!ret)
2655                 ret = err;
2656         return ret;
2657 }
2658
2659 static int ext4_write_dquot(struct dquot *dquot)
2660 {
2661         int ret, err;
2662         handle_t *handle;
2663         struct inode *inode;
2664
2665         inode = dquot_to_inode(dquot);
2666         handle = ext4_journal_start(inode,
2667                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
2668         if (IS_ERR(handle))
2669                 return PTR_ERR(handle);
2670         ret = dquot_commit(dquot);
2671         err = ext4_journal_stop(handle);
2672         if (!ret)
2673                 ret = err;
2674         return ret;
2675 }
2676
2677 static int ext4_acquire_dquot(struct dquot *dquot)
2678 {
2679         int ret, err;
2680         handle_t *handle;
2681
2682         handle = ext4_journal_start(dquot_to_inode(dquot),
2683                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
2684         if (IS_ERR(handle))
2685                 return PTR_ERR(handle);
2686         ret = dquot_acquire(dquot);
2687         err = ext4_journal_stop(handle);
2688         if (!ret)
2689                 ret = err;
2690         return ret;
2691 }
2692
2693 static int ext4_release_dquot(struct dquot *dquot)
2694 {
2695         int ret, err;
2696         handle_t *handle;
2697
2698         handle = ext4_journal_start(dquot_to_inode(dquot),
2699                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
2700         if (IS_ERR(handle))
2701                 return PTR_ERR(handle);
2702         ret = dquot_release(dquot);
2703         err = ext4_journal_stop(handle);
2704         if (!ret)
2705                 ret = err;
2706         return ret;
2707 }
2708
2709 static int ext4_mark_dquot_dirty(struct dquot *dquot)
2710 {
2711         /* Are we journalling quotas? */
2712         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
2713             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
2714                 dquot_mark_dquot_dirty(dquot);
2715                 return ext4_write_dquot(dquot);
2716         } else {
2717                 return dquot_mark_dquot_dirty(dquot);
2718         }
2719 }
2720
2721 static int ext4_write_info(struct super_block *sb, int type)
2722 {
2723         int ret, err;
2724         handle_t *handle;
2725
2726         /* Data block + inode block */
2727         handle = ext4_journal_start(sb->s_root->d_inode, 2);
2728         if (IS_ERR(handle))
2729                 return PTR_ERR(handle);
2730         ret = dquot_commit_info(sb, type);
2731         err = ext4_journal_stop(handle);
2732         if (!ret)
2733                 ret = err;
2734         return ret;
2735 }
2736
2737 /*
2738  * Turn on quotas during mount time - we need to find
2739  * the quota file and such...
2740  */
2741 static int ext4_quota_on_mount(struct super_block *sb, int type)
2742 {
2743         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
2744                         EXT4_SB(sb)->s_jquota_fmt, type);
2745 }
2746
2747 /*
2748  * Standard function to be called on quota_on
2749  */
2750 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
2751                          char *path)
2752 {
2753         int err;
2754         struct nameidata nd;
2755
2756         if (!test_opt(sb, QUOTA))
2757                 return -EINVAL;
2758         /* Not journalling quota? */
2759         if (!EXT4_SB(sb)->s_qf_names[USRQUOTA] &&
2760             !EXT4_SB(sb)->s_qf_names[GRPQUOTA])
2761                 return vfs_quota_on(sb, type, format_id, path);
2762         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
2763         if (err)
2764                 return err;
2765         /* Quotafile not on the same filesystem? */
2766         if (nd.mnt->mnt_sb != sb) {
2767                 path_release(&nd);
2768                 return -EXDEV;
2769         }
2770         /* Quotafile not of fs root? */
2771         if (nd.dentry->d_parent->d_inode != sb->s_root->d_inode)
2772                 printk(KERN_WARNING
2773                         "EXT4-fs: Quota file not on filesystem root. "
2774                         "Journalled quota will not work.\n");
2775         path_release(&nd);
2776         return vfs_quota_on(sb, type, format_id, path);
2777 }
2778
2779 /* Read data from quotafile - avoid pagecache and such because we cannot afford
2780  * acquiring the locks... As quota files are never truncated and quota code
2781  * itself serializes the operations (and noone else should touch the files)
2782  * we don't have to be afraid of races */
2783 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
2784                                size_t len, loff_t off)
2785 {
2786         struct inode *inode = sb_dqopt(sb)->files[type];
2787         sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
2788         int err = 0;
2789         int offset = off & (sb->s_blocksize - 1);
2790         int tocopy;
2791         size_t toread;
2792         struct buffer_head *bh;
2793         loff_t i_size = i_size_read(inode);
2794
2795         if (off > i_size)
2796                 return 0;
2797         if (off+len > i_size)
2798                 len = i_size-off;
2799         toread = len;
2800         while (toread > 0) {
2801                 tocopy = sb->s_blocksize - offset < toread ?
2802                                 sb->s_blocksize - offset : toread;
2803                 bh = ext4_bread(NULL, inode, blk, 0, &err);
2804                 if (err)
2805                         return err;
2806                 if (!bh)        /* A hole? */
2807                         memset(data, 0, tocopy);
2808                 else
2809                         memcpy(data, bh->b_data+offset, tocopy);
2810                 brelse(bh);
2811                 offset = 0;
2812                 toread -= tocopy;
2813                 data += tocopy;
2814                 blk++;
2815         }
2816         return len;
2817 }
2818
2819 /* Write to quotafile (we know the transaction is already started and has
2820  * enough credits) */
2821 static ssize_t ext4_quota_write(struct super_block *sb, int type,
2822                                 const char *data, size_t len, loff_t off)
2823 {
2824         struct inode *inode = sb_dqopt(sb)->files[type];
2825         sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
2826         int err = 0;
2827         int offset = off & (sb->s_blocksize - 1);
2828         int tocopy;
2829         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
2830         size_t towrite = len;
2831         struct buffer_head *bh;
2832         handle_t *handle = journal_current_handle();
2833
2834         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
2835         while (towrite > 0) {
2836                 tocopy = sb->s_blocksize - offset < towrite ?
2837                                 sb->s_blocksize - offset : towrite;
2838                 bh = ext4_bread(handle, inode, blk, 1, &err);
2839                 if (!bh)
2840                         goto out;
2841                 if (journal_quota) {
2842                         err = ext4_journal_get_write_access(handle, bh);
2843                         if (err) {
2844                                 brelse(bh);
2845                                 goto out;
2846                         }
2847                 }
2848                 lock_buffer(bh);
2849                 memcpy(bh->b_data+offset, data, tocopy);
2850                 flush_dcache_page(bh->b_page);
2851                 unlock_buffer(bh);
2852                 if (journal_quota)
2853                         err = ext4_journal_dirty_metadata(handle, bh);
2854                 else {
2855                         /* Always do at least ordered writes for quotas */
2856                         err = ext4_journal_dirty_data(handle, bh);
2857                         mark_buffer_dirty(bh);
2858                 }
2859                 brelse(bh);
2860                 if (err)
2861                         goto out;
2862                 offset = 0;
2863                 towrite -= tocopy;
2864                 data += tocopy;
2865                 blk++;
2866         }
2867 out:
2868         if (len == towrite)
2869                 return err;
2870         if (inode->i_size < off+len-towrite) {
2871                 i_size_write(inode, off+len-towrite);
2872                 EXT4_I(inode)->i_disksize = inode->i_size;
2873         }
2874         inode->i_version++;
2875         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2876         ext4_mark_inode_dirty(handle, inode);
2877         mutex_unlock(&inode->i_mutex);
2878         return len - towrite;
2879 }
2880
2881 #endif
2882
2883 static int ext4_get_sb(struct file_system_type *fs_type,
2884         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
2885 {
2886         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
2887 }
2888
2889 static struct file_system_type ext4dev_fs_type = {
2890         .owner          = THIS_MODULE,
2891         .name           = "ext4dev",
2892         .get_sb         = ext4_get_sb,
2893         .kill_sb        = kill_block_super,
2894         .fs_flags       = FS_REQUIRES_DEV,
2895 };
2896
2897 static int __init init_ext4_fs(void)
2898 {
2899         int err = init_ext4_xattr();
2900         if (err)
2901                 return err;
2902         err = init_inodecache();
2903         if (err)
2904                 goto out1;
2905         err = register_filesystem(&ext4dev_fs_type);
2906         if (err)
2907                 goto out;
2908         return 0;
2909 out:
2910         destroy_inodecache();
2911 out1:
2912         exit_ext4_xattr();
2913         return err;
2914 }
2915
2916 static void __exit exit_ext4_fs(void)
2917 {
2918         unregister_filesystem(&ext4dev_fs_type);
2919         destroy_inodecache();
2920         exit_ext4_xattr();
2921 }
2922
2923 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
2924 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
2925 MODULE_LICENSE("GPL");
2926 module_init(init_ext4_fs)
2927 module_exit(exit_ext4_fs)