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/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/parser.h>
  28 #include <linux/smp_lock.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/log2.h>
  38 #include <linux/crc16.h>
  39 #include <asm/uaccess.h>
  40
  41 #include "ext4.h"
  42 #include "ext4_jbd2.h"
  43 #include "xattr.h"
  44 #include "acl.h"
  45 #include "namei.h"
  46 #include "group.h"
  47
  48 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  49                              unsigned long journal_devnum);
  50 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  51                                unsigned int);
  52 static void ext4_commit_super (struct super_block * sb,
  53                                struct ext4_super_block * es,
  54                                int sync);
  55 static void ext4_mark_recovery_complete(struct super_block * sb,
  56                                         struct ext4_super_block * es);
  57 static void ext4_clear_journal_err(struct super_block * sb,
  58                                    struct ext4_super_block * es);
  59 static int ext4_sync_fs(struct super_block *sb, int wait);
  60 static const char *ext4_decode_error(struct super_block * sb, int errno,
  61                                      char nbuf[16]);
  62 static int ext4_remount (struct super_block * sb, int * flags, char * data);
  63 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf);
  64 static void ext4_unlockfs(struct super_block *sb);
  65 static void ext4_write_super (struct super_block * sb);
  66 static void ext4_write_super_lockfs(struct super_block *sb);
  67
  68
  69 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  70                                struct ext4_group_desc *bg)
  71 {
  72         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  73                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  74                 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  75 }
  76
  77 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  78                                struct ext4_group_desc *bg)
  79 {
  80         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  81                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  82                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  83 }
  84
  85 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  86                               struct ext4_group_desc *bg)
  87 {
  88         return le32_to_cpu(bg->bg_inode_table_lo) |
  89                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  90                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  91 }
  92
  93 void ext4_block_bitmap_set(struct super_block *sb,
  94                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
  95 {
  96         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
  97         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
  98                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
  99 }
 100
 101 void ext4_inode_bitmap_set(struct super_block *sb,
 102                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 103 {
 104         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 105         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 106                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 107 }
 108
 109 void ext4_inode_table_set(struct super_block *sb,
 110                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 111 {
 112         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 113         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 114                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 115 }
 116
 117 /*
 118  * Wrappers for jbd2_journal_start/end.
 119  *
 120  * The only special thing we need to do here is to make sure that all
 121  * journal_end calls result in the superblock being marked dirty, so
 122  * that sync() will call the filesystem's write_super callback if
 123  * appropriate.
 124  */
 125 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 126 {
 127         journal_t *journal;
 128
 129         if (sb->s_flags & MS_RDONLY)
 130                 return ERR_PTR(-EROFS);
 131
 132         /* Special case here: if the journal has aborted behind our
 133          * backs (eg. EIO in the commit thread), then we still need to
 134          * take the FS itself readonly cleanly. */
 135         journal = EXT4_SB(sb)->s_journal;
 136         if (is_journal_aborted(journal)) {
 137                 ext4_abort(sb, __func__,
 138                            "Detected aborted journal");
 139                 return ERR_PTR(-EROFS);
 140         }
 141
 142         return jbd2_journal_start(journal, nblocks);
 143 }
 144
 145 /*
 146  * The only special thing we need to do here is to make sure that all
 147  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 148  * that sync() will call the filesystem's write_super callback if
 149  * appropriate.
 150  */
 151 int __ext4_journal_stop(const char *where, handle_t *handle)
 152 {
 153         struct super_block *sb;
 154         int err;
 155         int rc;
 156
 157         sb = handle->h_transaction->t_journal->j_private;
 158         err = handle->h_err;
 159         rc = jbd2_journal_stop(handle);
 160
 161         if (!err)
 162                 err = rc;
 163         if (err)
 164                 __ext4_std_error(sb, where, err);
 165         return err;
 166 }
 167
 168 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 169                 struct buffer_head *bh, handle_t *handle, int err)
 170 {
 171         char nbuf[16];
 172         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 173
 174         if (bh)
 175                 BUFFER_TRACE(bh, "abort");
 176
 177         if (!handle->h_err)
 178                 handle->h_err = err;
 179
 180         if (is_handle_aborted(handle))
 181                 return;
 182
 183         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 184                caller, errstr, err_fn);
 185
 186         jbd2_journal_abort_handle(handle);
 187 }
 188
 189 /* Deal with the reporting of failure conditions on a filesystem such as
 190  * inconsistencies detected or read IO failures.
 191  *
 192  * On ext2, we can store the error state of the filesystem in the
 193  * superblock.  That is not possible on ext4, because we may have other
 194  * write ordering constraints on the superblock which prevent us from
 195  * writing it out straight away; and given that the journal is about to
 196  * be aborted, we can't rely on the current, or future, transactions to
 197  * write out the superblock safely.
 198  *
 199  * We'll just use the jbd2_journal_abort() error code to record an error in
 200  * the journal instead.  On recovery, the journal will compain about
 201  * that error until we've noted it down and cleared it.
 202  */
 203
 204 static void ext4_handle_error(struct super_block *sb)
 205 {
 206         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 207
 208         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 209         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 210
 211         if (sb->s_flags & MS_RDONLY)
 212                 return;
 213
 214         if (!test_opt (sb, ERRORS_CONT)) {
 215                 journal_t *journal = EXT4_SB(sb)->s_journal;
 216
 217                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 218                 if (journal)
 219                         jbd2_journal_abort(journal, -EIO);
 220         }
 221         if (test_opt (sb, ERRORS_RO)) {
 222                 printk (KERN_CRIT "Remounting filesystem read-only\n");
 223                 sb->s_flags |= MS_RDONLY;
 224         }
 225         ext4_commit_super(sb, es, 1);
 226         if (test_opt(sb, ERRORS_PANIC))
 227                 panic("EXT4-fs (device %s): panic forced after error\n",
 228                         sb->s_id);
 229 }
 230
 231 void ext4_error (struct super_block * sb, const char * function,
 232                  const char * fmt, ...)
 233 {
 234         va_list args;
 235
 236         va_start(args, fmt);
 237         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 238         vprintk(fmt, args);
 239         printk("\n");
 240         va_end(args);
 241
 242         ext4_handle_error(sb);
 243 }
 244
 245 static const char *ext4_decode_error(struct super_block * sb, int errno,
 246                                      char nbuf[16])
 247 {
 248         char *errstr = NULL;
 249
 250         switch (errno) {
 251         case -EIO:
 252                 errstr = "IO failure";
 253                 break;
 254         case -ENOMEM:
 255                 errstr = "Out of memory";
 256                 break;
 257         case -EROFS:
 258                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 259                         errstr = "Journal has aborted";
 260                 else
 261                         errstr = "Readonly filesystem";
 262                 break;
 263         default:
 264                 /* If the caller passed in an extra buffer for unknown
 265                  * errors, textualise them now.  Else we just return
 266                  * NULL. */
 267                 if (nbuf) {
 268                         /* Check for truncated error codes... */
 269                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 270                                 errstr = nbuf;
 271                 }
 272                 break;
 273         }
 274
 275         return errstr;
 276 }
 277
 278 /* __ext4_std_error decodes expected errors from journaling functions
 279  * automatically and invokes the appropriate error response.  */
 280
 281 void __ext4_std_error (struct super_block * sb, const char * function,
 282                        int errno)
 283 {
 284         char nbuf[16];
 285         const char *errstr;
 286
 287         /* Special case: if the error is EROFS, and we're not already
 288          * inside a transaction, then there's really no point in logging
 289          * an error. */
 290         if (errno == -EROFS && journal_current_handle() == NULL &&
 291             (sb->s_flags & MS_RDONLY))
 292                 return;
 293
 294         errstr = ext4_decode_error(sb, errno, nbuf);
 295         printk (KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 296                 sb->s_id, function, errstr);
 297
 298         ext4_handle_error(sb);
 299 }
 300
 301 /*
 302  * ext4_abort is a much stronger failure handler than ext4_error.  The
 303  * abort function may be used to deal with unrecoverable failures such
 304  * as journal IO errors or ENOMEM at a critical moment in log management.
 305  *
 306  * We unconditionally force the filesystem into an ABORT|READONLY state,
 307  * unless the error response on the fs has been set to panic in which
 308  * case we take the easy way out and panic immediately.
 309  */
 310
 311 void ext4_abort (struct super_block * sb, const char * function,
 312                  const char * fmt, ...)
 313 {
 314         va_list args;
 315
 316         printk (KERN_CRIT "ext4_abort called.\n");
 317
 318         va_start(args, fmt);
 319         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 320         vprintk(fmt, args);
 321         printk("\n");
 322         va_end(args);
 323
 324         if (test_opt(sb, ERRORS_PANIC))
 325                 panic("EXT4-fs panic from previous error\n");
 326
 327         if (sb->s_flags & MS_RDONLY)
 328                 return;
 329
 330         printk(KERN_CRIT "Remounting filesystem read-only\n");
 331         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 332         sb->s_flags |= MS_RDONLY;
 333         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 334         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 335 }
 336
 337 void ext4_warning (struct super_block * sb, const char * function,
 338                    const char * fmt, ...)
 339 {
 340         va_list args;
 341
 342         va_start(args, fmt);
 343         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 344                sb->s_id, function);
 345         vprintk(fmt, args);
 346         printk("\n");
 347         va_end(args);
 348 }
 349
 350 void ext4_update_dynamic_rev(struct super_block *sb)
 351 {
 352         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 353
 354         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 355                 return;
 356
 357         ext4_warning(sb, __func__,
 358                      "updating to rev %d because of new feature flag, "
 359                      "running e2fsck is recommended",
 360                      EXT4_DYNAMIC_REV);
 361
 362         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 363         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 364         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 365         /* leave es->s_feature_*compat flags alone */
 366         /* es->s_uuid will be set by e2fsck if empty */
 367
 368         /*
 369          * The rest of the superblock fields should be zero, and if not it
 370          * means they are likely already in use, so leave them alone.  We
 371          * can leave it up to e2fsck to clean up any inconsistencies there.
 372          */
 373 }
 374
 375 int ext4_update_compat_feature(handle_t *handle,
 376                                         struct super_block *sb, __u32 compat)
 377 {
 378         int err = 0;
 379         if (!EXT4_HAS_COMPAT_FEATURE(sb, compat)) {
 380                 err = ext4_journal_get_write_access(handle,
 381                                 EXT4_SB(sb)->s_sbh);
 382                 if (err)
 383                         return err;
 384                 EXT4_SET_COMPAT_FEATURE(sb, compat);
 385                 sb->s_dirt = 1;
 386                 handle->h_sync = 1;
 387                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 388                                         "call ext4_journal_dirty_met adata");
 389                 err = ext4_journal_dirty_metadata(handle,
 390                                 EXT4_SB(sb)->s_sbh);
 391         }
 392         return err;
 393 }
 394
 395 int ext4_update_rocompat_feature(handle_t *handle,
 396                                         struct super_block *sb, __u32 rocompat)
 397 {
 398         int err = 0;
 399         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, rocompat)) {
 400                 err = ext4_journal_get_write_access(handle,
 401                                 EXT4_SB(sb)->s_sbh);
 402                 if (err)
 403                         return err;
 404                 EXT4_SET_RO_COMPAT_FEATURE(sb, rocompat);
 405                 sb->s_dirt = 1;
 406                 handle->h_sync = 1;
 407                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 408                                         "call ext4_journal_dirty_met adata");
 409                 err = ext4_journal_dirty_metadata(handle,
 410                                 EXT4_SB(sb)->s_sbh);
 411         }
 412         return err;
 413 }
 414
 415 int ext4_update_incompat_feature(handle_t *handle,
 416                                         struct super_block *sb, __u32 incompat)
 417 {
 418         int err = 0;
 419         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, incompat)) {
 420                 err = ext4_journal_get_write_access(handle,
 421                                 EXT4_SB(sb)->s_sbh);
 422                 if (err)
 423                         return err;
 424                 EXT4_SET_INCOMPAT_FEATURE(sb, incompat);
 425                 sb->s_dirt = 1;
 426                 handle->h_sync = 1;
 427                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 428                                         "call ext4_journal_dirty_met adata");
 429                 err = ext4_journal_dirty_metadata(handle,
 430                                 EXT4_SB(sb)->s_sbh);
 431         }
 432         return err;
 433 }
 434
 435 /*
 436  * Open the external journal device
 437  */
 438 static struct block_device *ext4_blkdev_get(dev_t dev)
 439 {
 440         struct block_device *bdev;
 441         char b[BDEVNAME_SIZE];
 442
 443         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 444         if (IS_ERR(bdev))
 445                 goto fail;
 446         return bdev;
 447
 448 fail:
 449         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 450                         __bdevname(dev, b), PTR_ERR(bdev));
 451         return NULL;
 452 }
 453
 454 /*
 455  * Release the journal device
 456  */
 457 static int ext4_blkdev_put(struct block_device *bdev)
 458 {
 459         bd_release(bdev);
 460         return blkdev_put(bdev);
 461 }
 462
 463 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 464 {
 465         struct block_device *bdev;
 466         int ret = -ENODEV;
 467
 468         bdev = sbi->journal_bdev;
 469         if (bdev) {
 470                 ret = ext4_blkdev_put(bdev);
 471                 sbi->journal_bdev = NULL;
 472         }
 473         return ret;
 474 }
 475
 476 static inline struct inode *orphan_list_entry(struct list_head *l)
 477 {
 478         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 479 }
 480
 481 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 482 {
 483         struct list_head *l;
 484
 485         printk(KERN_ERR "sb orphan head is %d\n",
 486                le32_to_cpu(sbi->s_es->s_last_orphan));
 487
 488         printk(KERN_ERR "sb_info orphan list:\n");
 489         list_for_each(l, &sbi->s_orphan) {
 490                 struct inode *inode = orphan_list_entry(l);
 491                 printk(KERN_ERR "  "
 492                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 493                        inode->i_sb->s_id, inode->i_ino, inode,
 494                        inode->i_mode, inode->i_nlink,
 495                        NEXT_ORPHAN(inode));
 496         }
 497 }
 498
 499 static void ext4_put_super (struct super_block * sb)
 500 {
 501         struct ext4_sb_info *sbi = EXT4_SB(sb);
 502         struct ext4_super_block *es = sbi->s_es;
 503         int i;
 504
 505         ext4_mb_release(sb);
 506         ext4_ext_release(sb);
 507         ext4_xattr_put_super(sb);
 508         jbd2_journal_destroy(sbi->s_journal);
 509         sbi->s_journal = NULL;
 510         if (!(sb->s_flags & MS_RDONLY)) {
 511                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 512                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 513                 BUFFER_TRACE(sbi->s_sbh, "marking dirty");
 514                 mark_buffer_dirty(sbi->s_sbh);
 515                 ext4_commit_super(sb, es, 1);
 516         }
 517
 518         for (i = 0; i < sbi->s_gdb_count; i++)
 519                 brelse(sbi->s_group_desc[i]);
 520         kfree(sbi->s_group_desc);
 521         kfree(sbi->s_flex_groups);
 522         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 523         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 524         percpu_counter_destroy(&sbi->s_dirs_counter);
 525         brelse(sbi->s_sbh);
 526 #ifdef CONFIG_QUOTA
 527         for (i = 0; i < MAXQUOTAS; i++)
 528                 kfree(sbi->s_qf_names[i]);
 529 #endif
 530
 531         /* Debugging code just in case the in-memory inode orphan list
 532          * isn't empty.  The on-disk one can be non-empty if we've
 533          * detected an error and taken the fs readonly, but the
 534          * in-memory list had better be clean by this point. */
 535         if (!list_empty(&sbi->s_orphan))
 536                 dump_orphan_list(sb, sbi);
 537         J_ASSERT(list_empty(&sbi->s_orphan));
 538
 539         invalidate_bdev(sb->s_bdev);
 540         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 541                 /*
 542                  * Invalidate the journal device's buffers.  We don't want them
 543                  * floating about in memory - the physical journal device may
 544                  * hotswapped, and it breaks the `ro-after' testing code.
 545                  */
 546                 sync_blockdev(sbi->journal_bdev);
 547                 invalidate_bdev(sbi->journal_bdev);
 548                 ext4_blkdev_remove(sbi);
 549         }
 550         sb->s_fs_info = NULL;
 551         kfree(sbi);
 552         return;
 553 }
 554
 555 static struct kmem_cache *ext4_inode_cachep;
 556
 557 /*
 558  * Called inside transaction, so use GFP_NOFS
 559  */
 560 static struct inode *ext4_alloc_inode(struct super_block *sb)
 561 {
 562         struct ext4_inode_info *ei;
 563
 564         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 565         if (!ei)
 566                 return NULL;
 567 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 568         ei->i_acl = EXT4_ACL_NOT_CACHED;
 569         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 570 #endif
 571         ei->i_block_alloc_info = NULL;
 572         ei->vfs_inode.i_version = 1;
 573         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 574         INIT_LIST_HEAD(&ei->i_prealloc_list);
 575         spin_lock_init(&ei->i_prealloc_lock);
 576         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 577         ei->i_reserved_data_blocks = 0;
 578         ei->i_reserved_meta_blocks = 0;
 579         ei->i_allocated_meta_blocks = 0;
 580         ei->i_delalloc_reserved_flag = 0;
 581         spin_lock_init(&(ei->i_block_reservation_lock));
 582         return &ei->vfs_inode;
 583 }
 584
 585 static void ext4_destroy_inode(struct inode *inode)
 586 {
 587         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 588                 printk("EXT4 Inode %p: orphan list check failed!\n",
 589                         EXT4_I(inode));
 590                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 591                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 592                                 true);
 593                 dump_stack();
 594         }
 595         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 596 }
 597
 598 static void init_once(struct kmem_cache *cachep, void *foo)
 599 {
 600         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 601
 602         INIT_LIST_HEAD(&ei->i_orphan);
 603 #ifdef CONFIG_EXT4DEV_FS_XATTR
 604         init_rwsem(&ei->xattr_sem);
 605 #endif
 606         init_rwsem(&ei->i_data_sem);
 607         inode_init_once(&ei->vfs_inode);
 608 }
 609
 610 static int init_inodecache(void)
 611 {
 612         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 613                                              sizeof(struct ext4_inode_info),
 614                                              0, (SLAB_RECLAIM_ACCOUNT|
 615                                                 SLAB_MEM_SPREAD),
 616                                              init_once);
 617         if (ext4_inode_cachep == NULL)
 618                 return -ENOMEM;
 619         return 0;
 620 }
 621
 622 static void destroy_inodecache(void)
 623 {
 624         kmem_cache_destroy(ext4_inode_cachep);
 625 }
 626
 627 static void ext4_clear_inode(struct inode *inode)
 628 {
 629         struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
 630 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 631         if (EXT4_I(inode)->i_acl &&
 632                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 633                 posix_acl_release(EXT4_I(inode)->i_acl);
 634                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 635         }
 636         if (EXT4_I(inode)->i_default_acl &&
 637                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 638                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 639                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 640         }
 641 #endif
 642         ext4_discard_reservation(inode);
 643         EXT4_I(inode)->i_block_alloc_info = NULL;
 644         if (unlikely(rsv))
 645                 kfree(rsv);
 646         jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 647                                        &EXT4_I(inode)->jinode);
 648 }
 649
 650 static inline void ext4_show_quota_options(struct seq_file *seq, struct super_block *sb)
 651 {
 652 #if defined(CONFIG_QUOTA)
 653         struct ext4_sb_info *sbi = EXT4_SB(sb);
 654
 655         if (sbi->s_jquota_fmt)
 656                 seq_printf(seq, ",jqfmt=%s",
 657                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");
 658
 659         if (sbi->s_qf_names[USRQUOTA])
 660                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 661
 662         if (sbi->s_qf_names[GRPQUOTA])
 663                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 664
 665         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 666                 seq_puts(seq, ",usrquota");
 667
 668         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 669                 seq_puts(seq, ",grpquota");
 670 #endif
 671 }
 672
 673 /*
 674  * Show an option if
 675  *  - it's set to a non-default value OR
 676  *  - if the per-sb default is different from the global default
 677  */
 678 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 679 {
 680         int def_errors;
 681         unsigned long def_mount_opts;
 682         struct super_block *sb = vfs->mnt_sb;
 683         struct ext4_sb_info *sbi = EXT4_SB(sb);
 684         struct ext4_super_block *es = sbi->s_es;
 685
 686         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 687         def_errors     = le16_to_cpu(es->s_errors);
 688
 689         if (sbi->s_sb_block != 1)
 690                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 691         if (test_opt(sb, MINIX_DF))
 692                 seq_puts(seq, ",minixdf");
 693         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 694                 seq_puts(seq, ",grpid");
 695         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 696                 seq_puts(seq, ",nogrpid");
 697         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 698             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 699                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 700         }
 701         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 702             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 703                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 704         }
 705         if (test_opt(sb, ERRORS_RO)) {
 706                 if (def_errors == EXT4_ERRORS_PANIC ||
 707                     def_errors == EXT4_ERRORS_CONTINUE) {
 708                         seq_puts(seq, ",errors=remount-ro");
 709                 }
 710         }
 711         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 712                 seq_puts(seq, ",errors=continue");
 713         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 714                 seq_puts(seq, ",errors=panic");
 715         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 716                 seq_puts(seq, ",nouid32");
 717         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 718                 seq_puts(seq, ",debug");
 719         if (test_opt(sb, OLDALLOC))
 720                 seq_puts(seq, ",oldalloc");
 721 #ifdef CONFIG_EXT4DEV_FS_XATTR
 722         if (test_opt(sb, XATTR_USER) &&
 723                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 724                 seq_puts(seq, ",user_xattr");
 725         if (!test_opt(sb, XATTR_USER) &&
 726             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 727                 seq_puts(seq, ",nouser_xattr");
 728         }
 729 #endif
 730 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 731         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 732                 seq_puts(seq, ",acl");
 733         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 734                 seq_puts(seq, ",noacl");
 735 #endif
 736         if (!test_opt(sb, RESERVATION))
 737                 seq_puts(seq, ",noreservation");
 738         if (sbi->s_commit_interval) {
 739                 seq_printf(seq, ",commit=%u",
 740                            (unsigned) (sbi->s_commit_interval / HZ));
 741         }
 742         /*
 743          * We're changing the default of barrier mount option, so
 744          * let's always display its mount state so it's clear what its
 745          * status is.
 746          */
 747         seq_puts(seq, ",barrier=");
 748         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 749         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 750                 seq_puts(seq, ",journal_async_commit");
 751         if (test_opt(sb, NOBH))
 752                 seq_puts(seq, ",nobh");
 753         if (!test_opt(sb, EXTENTS))
 754                 seq_puts(seq, ",noextents");
 755         if (!test_opt(sb, MBALLOC))
 756                 seq_puts(seq, ",nomballoc");
 757         if (test_opt(sb, I_VERSION))
 758                 seq_puts(seq, ",i_version");
 759         if (!test_opt(sb, DELALLOC))
 760                 seq_puts(seq, ",nodelalloc");
 761
 762
 763         if (sbi->s_stripe)
 764                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 765         /*
 766          * journal mode get enabled in different ways
 767          * So just print the value even if we didn't specify it
 768          */
 769         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 770                 seq_puts(seq, ",data=journal");
 771         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 772                 seq_puts(seq, ",data=ordered");
 773         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 774                 seq_puts(seq, ",data=writeback");
 775
 776         ext4_show_quota_options(seq, sb);
 777         return 0;
 778 }
 779
 780
 781 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 782                 u64 ino, u32 generation)
 783 {
 784         struct inode *inode;
 785
 786         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 787                 return ERR_PTR(-ESTALE);
 788         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 789                 return ERR_PTR(-ESTALE);
 790
 791         /* iget isn't really right if the inode is currently unallocated!!
 792          *
 793          * ext4_read_inode will return a bad_inode if the inode had been
 794          * deleted, so we should be safe.
 795          *
 796          * Currently we don't know the generation for parent directory, so
 797          * a generation of 0 means "accept any"
 798          */
 799         inode = ext4_iget(sb, ino);
 800         if (IS_ERR(inode))
 801                 return ERR_CAST(inode);
 802         if (generation && inode->i_generation != generation) {
 803                 iput(inode);
 804                 return ERR_PTR(-ESTALE);
 805         }
 806
 807         return inode;
 808 }
 809
 810 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 811                 int fh_len, int fh_type)
 812 {
 813         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 814                                     ext4_nfs_get_inode);
 815 }
 816
 817 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 818                 int fh_len, int fh_type)
 819 {
 820         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 821                                     ext4_nfs_get_inode);
 822 }
 823
 824 #ifdef CONFIG_QUOTA
 825 #define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
 826 #define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 827
 828 static int ext4_dquot_initialize(struct inode *inode, int type);
 829 static int ext4_dquot_drop(struct inode *inode);
 830 static int ext4_write_dquot(struct dquot *dquot);
 831 static int ext4_acquire_dquot(struct dquot *dquot);
 832 static int ext4_release_dquot(struct dquot *dquot);
 833 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 834 static int ext4_write_info(struct super_block *sb, int type);
 835 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 836                                 char *path, int remount);
 837 static int ext4_quota_on_mount(struct super_block *sb, int type);
 838 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 839                                size_t len, loff_t off);
 840 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 841                                 const char *data, size_t len, loff_t off);
 842
 843 static struct dquot_operations ext4_quota_operations = {
 844         .initialize     = ext4_dquot_initialize,
 845         .drop           = ext4_dquot_drop,
 846         .alloc_space    = dquot_alloc_space,
 847         .alloc_inode    = dquot_alloc_inode,
 848         .free_space     = dquot_free_space,
 849         .free_inode     = dquot_free_inode,
 850         .transfer       = dquot_transfer,
 851         .write_dquot    = ext4_write_dquot,
 852         .acquire_dquot  = ext4_acquire_dquot,
 853         .release_dquot  = ext4_release_dquot,
 854         .mark_dirty     = ext4_mark_dquot_dirty,
 855         .write_info     = ext4_write_info
 856 };
 857
 858 static struct quotactl_ops ext4_qctl_operations = {
 859         .quota_on       = ext4_quota_on,
 860         .quota_off      = vfs_quota_off,
 861         .quota_sync     = vfs_quota_sync,
 862         .get_info       = vfs_get_dqinfo,
 863         .set_info       = vfs_set_dqinfo,
 864         .get_dqblk      = vfs_get_dqblk,
 865         .set_dqblk      = vfs_set_dqblk
 866 };
 867 #endif
 868
 869 static const struct super_operations ext4_sops = {
 870         .alloc_inode    = ext4_alloc_inode,
 871         .destroy_inode  = ext4_destroy_inode,
 872         .write_inode    = ext4_write_inode,
 873         .dirty_inode    = ext4_dirty_inode,
 874         .delete_inode   = ext4_delete_inode,
 875         .put_super      = ext4_put_super,
 876         .write_super    = ext4_write_super,
 877         .sync_fs        = ext4_sync_fs,
 878         .write_super_lockfs = ext4_write_super_lockfs,
 879         .unlockfs       = ext4_unlockfs,
 880         .statfs         = ext4_statfs,
 881         .remount_fs     = ext4_remount,
 882         .clear_inode    = ext4_clear_inode,
 883         .show_options   = ext4_show_options,
 884 #ifdef CONFIG_QUOTA
 885         .quota_read     = ext4_quota_read,
 886         .quota_write    = ext4_quota_write,
 887 #endif
 888 };
 889
 890 static const struct export_operations ext4_export_ops = {
 891         .fh_to_dentry = ext4_fh_to_dentry,
 892         .fh_to_parent = ext4_fh_to_parent,
 893         .get_parent = ext4_get_parent,
 894 };
 895
 896 enum {
 897         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 898         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 899         Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
 900         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 901         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 902         Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 903         Opt_journal_checksum, Opt_journal_async_commit,
 904         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 905         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 906         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 907         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 908         Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
 909         Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_delalloc, Opt_nodelalloc,
 910 };
 911
 912 static match_table_t tokens = {
 913         {Opt_bsd_df, "bsddf"},
 914         {Opt_minix_df, "minixdf"},
 915         {Opt_grpid, "grpid"},
 916         {Opt_grpid, "bsdgroups"},
 917         {Opt_nogrpid, "nogrpid"},
 918         {Opt_nogrpid, "sysvgroups"},
 919         {Opt_resgid, "resgid=%u"},
 920         {Opt_resuid, "resuid=%u"},
 921         {Opt_sb, "sb=%u"},
 922         {Opt_err_cont, "errors=continue"},
 923         {Opt_err_panic, "errors=panic"},
 924         {Opt_err_ro, "errors=remount-ro"},
 925         {Opt_nouid32, "nouid32"},
 926         {Opt_nocheck, "nocheck"},
 927         {Opt_nocheck, "check=none"},
 928         {Opt_debug, "debug"},
 929         {Opt_oldalloc, "oldalloc"},
 930         {Opt_orlov, "orlov"},
 931         {Opt_user_xattr, "user_xattr"},
 932         {Opt_nouser_xattr, "nouser_xattr"},
 933         {Opt_acl, "acl"},
 934         {Opt_noacl, "noacl"},
 935         {Opt_reservation, "reservation"},
 936         {Opt_noreservation, "noreservation"},
 937         {Opt_noload, "noload"},
 938         {Opt_nobh, "nobh"},
 939         {Opt_bh, "bh"},
 940         {Opt_commit, "commit=%u"},
 941         {Opt_journal_update, "journal=update"},
 942         {Opt_journal_inum, "journal=%u"},
 943         {Opt_journal_dev, "journal_dev=%u"},
 944         {Opt_journal_checksum, "journal_checksum"},
 945         {Opt_journal_async_commit, "journal_async_commit"},
 946         {Opt_abort, "abort"},
 947         {Opt_data_journal, "data=journal"},
 948         {Opt_data_ordered, "data=ordered"},
 949         {Opt_data_writeback, "data=writeback"},
 950         {Opt_offusrjquota, "usrjquota="},
 951         {Opt_usrjquota, "usrjquota=%s"},
 952         {Opt_offgrpjquota, "grpjquota="},
 953         {Opt_grpjquota, "grpjquota=%s"},
 954         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 955         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 956         {Opt_grpquota, "grpquota"},
 957         {Opt_noquota, "noquota"},
 958         {Opt_quota, "quota"},
 959         {Opt_usrquota, "usrquota"},
 960         {Opt_barrier, "barrier=%u"},
 961         {Opt_extents, "extents"},
 962         {Opt_noextents, "noextents"},
 963         {Opt_i_version, "i_version"},
 964         {Opt_mballoc, "mballoc"},
 965         {Opt_nomballoc, "nomballoc"},
 966         {Opt_stripe, "stripe=%u"},
 967         {Opt_resize, "resize"},
 968         {Opt_delalloc, "delalloc"},
 969         {Opt_nodelalloc, "nodelalloc"},
 970         {Opt_err, NULL},
 971 };
 972
 973 static ext4_fsblk_t get_sb_block(void **data)
 974 {
 975         ext4_fsblk_t    sb_block;
 976         char            *options = (char *) *data;
 977
 978         if (!options || strncmp(options, "sb=", 3) != 0)
 979                 return 1;       /* Default location */
 980         options += 3;
 981         /*todo: use simple_strtoll with >32bit ext4 */
 982         sb_block = simple_strtoul(options, &options, 0);
 983         if (*options && *options != ',') {
 984                 printk("EXT4-fs: Invalid sb specification: %s\n",
 985                        (char *) *data);
 986                 return 1;
 987         }
 988         if (*options == ',')
 989                 options++;
 990         *data = (void *) options;
 991         return sb_block;
 992 }
 993
 994 static int parse_options (char *options, struct super_block *sb,
 995                           unsigned int *inum, unsigned long *journal_devnum,
 996                           ext4_fsblk_t *n_blocks_count, int is_remount)
 997 {
 998         struct ext4_sb_info *sbi = EXT4_SB(sb);
 999         char * p;
1000         substring_t args[MAX_OPT_ARGS];
1001         int data_opt = 0;
1002         int option;
1003 #ifdef CONFIG_QUOTA
1004         int qtype, qfmt;
1005         char *qname;
1006 #endif
1007
1008         if (!options)
1009                 return 1;
1010
1011         while ((p = strsep (&options, ",")) != NULL) {
1012                 int token;
1013                 if (!*p)
1014                         continue;
1015
1016                 token = match_token(p, tokens, args);
1017                 switch (token) {
1018                 case Opt_bsd_df:
1019                         clear_opt (sbi->s_mount_opt, MINIX_DF);
1020                         break;
1021                 case Opt_minix_df:
1022                         set_opt (sbi->s_mount_opt, MINIX_DF);
1023                         break;
1024                 case Opt_grpid:
1025                         set_opt (sbi->s_mount_opt, GRPID);
1026                         break;
1027                 case Opt_nogrpid:
1028                         clear_opt (sbi->s_mount_opt, GRPID);
1029                         break;
1030                 case Opt_resuid:
1031                         if (match_int(&args[0], &option))
1032                                 return 0;
1033                         sbi->s_resuid = option;
1034                         break;
1035                 case Opt_resgid:
1036                         if (match_int(&args[0], &option))
1037                                 return 0;
1038                         sbi->s_resgid = option;
1039                         break;
1040                 case Opt_sb:
1041                         /* handled by get_sb_block() instead of here */
1042                         /* *sb_block = match_int(&args[0]); */
1043                         break;
1044                 case Opt_err_panic:
1045                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
1046                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
1047                         set_opt (sbi->s_mount_opt, ERRORS_PANIC);
1048                         break;
1049                 case Opt_err_ro:
1050                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
1051                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
1052                         set_opt (sbi->s_mount_opt, ERRORS_RO);
1053                         break;
1054                 case Opt_err_cont:
1055                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
1056                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
1057                         set_opt (sbi->s_mount_opt, ERRORS_CONT);
1058                         break;
1059                 case Opt_nouid32:
1060                         set_opt (sbi->s_mount_opt, NO_UID32);
1061                         break;
1062                 case Opt_nocheck:
1063                         clear_opt (sbi->s_mount_opt, CHECK);
1064                         break;
1065                 case Opt_debug:
1066                         set_opt (sbi->s_mount_opt, DEBUG);
1067                         break;
1068                 case Opt_oldalloc:
1069                         set_opt (sbi->s_mount_opt, OLDALLOC);
1070                         break;
1071                 case Opt_orlov:
1072                         clear_opt (sbi->s_mount_opt, OLDALLOC);
1073                         break;
1074 #ifdef CONFIG_EXT4DEV_FS_XATTR
1075                 case Opt_user_xattr:
1076                         set_opt (sbi->s_mount_opt, XATTR_USER);
1077                         break;
1078                 case Opt_nouser_xattr:
1079                         clear_opt (sbi->s_mount_opt, XATTR_USER);
1080                         break;
1081 #else
1082                 case Opt_user_xattr:
1083                 case Opt_nouser_xattr:
1084                         printk("EXT4 (no)user_xattr options not supported\n");
1085                         break;
1086 #endif
1087 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1088                 case Opt_acl:
1089                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1090                         break;
1091                 case Opt_noacl:
1092                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1093                         break;
1094 #else
1095                 case Opt_acl:
1096                 case Opt_noacl:
1097                         printk("EXT4 (no)acl options not supported\n");
1098                         break;
1099 #endif
1100                 case Opt_reservation:
1101                         set_opt(sbi->s_mount_opt, RESERVATION);
1102                         break;
1103                 case Opt_noreservation:
1104                         clear_opt(sbi->s_mount_opt, RESERVATION);
1105                         break;
1106                 case Opt_journal_update:
1107                         /* @@@ FIXME */
1108                         /* Eventually we will want to be able to create
1109                            a journal file here.  For now, only allow the
1110                            user to specify an existing inode to be the
1111                            journal file. */
1112                         if (is_remount) {
1113                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1114                                        "journal on remount\n");
1115                                 return 0;
1116                         }
1117                         set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
1118                         break;
1119                 case Opt_journal_inum:
1120                         if (is_remount) {
1121                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1122                                        "journal on remount\n");
1123                                 return 0;
1124                         }
1125                         if (match_int(&args[0], &option))
1126                                 return 0;
1127                         *inum = option;
1128                         break;
1129                 case Opt_journal_dev:
1130                         if (is_remount) {
1131                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1132                                        "journal on remount\n");
1133                                 return 0;
1134                         }
1135                         if (match_int(&args[0], &option))
1136                                 return 0;
1137                         *journal_devnum = option;
1138                         break;
1139                 case Opt_journal_checksum:
1140                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1141                         break;
1142                 case Opt_journal_async_commit:
1143                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1144                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1145                         break;
1146                 case Opt_noload:
1147                         set_opt (sbi->s_mount_opt, NOLOAD);
1148                         break;
1149                 case Opt_commit:
1150                         if (match_int(&args[0], &option))
1151                                 return 0;
1152                         if (option < 0)
1153                                 return 0;
1154                         if (option == 0)
1155                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1156                         sbi->s_commit_interval = HZ * option;
1157                         break;
1158                 case Opt_data_journal:
1159                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1160                         goto datacheck;
1161                 case Opt_data_ordered:
1162                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1163                         goto datacheck;
1164                 case Opt_data_writeback:
1165                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1166                 datacheck:
1167                         if (is_remount) {
1168                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1169                                                 != data_opt) {
1170                                         printk(KERN_ERR
1171                                                 "EXT4-fs: cannot change data "
1172                                                 "mode on remount\n");
1173                                         return 0;
1174                                 }
1175                         } else {
1176                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1177                                 sbi->s_mount_opt |= data_opt;
1178                         }
1179                         break;
1180 #ifdef CONFIG_QUOTA
1181                 case Opt_usrjquota:
1182                         qtype = USRQUOTA;
1183                         goto set_qf_name;
1184                 case Opt_grpjquota:
1185                         qtype = GRPQUOTA;
1186 set_qf_name:
1187                         if ((sb_any_quota_enabled(sb) ||
1188                              sb_any_quota_suspended(sb)) &&
1189                             !sbi->s_qf_names[qtype]) {
1190                                 printk(KERN_ERR
1191                                         "EXT4-fs: Cannot change journaled "
1192                                         "quota options when quota turned on.\n");
1193                                 return 0;
1194                         }
1195                         qname = match_strdup(&args[0]);
1196                         if (!qname) {
1197                                 printk(KERN_ERR
1198                                         "EXT4-fs: not enough memory for "
1199                                         "storing quotafile name.\n");
1200                                 return 0;
1201                         }
1202                         if (sbi->s_qf_names[qtype] &&
1203                             strcmp(sbi->s_qf_names[qtype], qname)) {
1204                                 printk(KERN_ERR
1205                                         "EXT4-fs: %s quota file already "
1206                                         "specified.\n", QTYPE2NAME(qtype));
1207                                 kfree(qname);
1208                                 return 0;
1209                         }
1210                         sbi->s_qf_names[qtype] = qname;
1211                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1212                                 printk(KERN_ERR
1213                                         "EXT4-fs: quotafile must be on "
1214                                         "filesystem root.\n");
1215                                 kfree(sbi->s_qf_names[qtype]);
1216                                 sbi->s_qf_names[qtype] = NULL;
1217                                 return 0;
1218                         }
1219                         set_opt(sbi->s_mount_opt, QUOTA);
1220                         break;
1221                 case Opt_offusrjquota:
1222                         qtype = USRQUOTA;
1223                         goto clear_qf_name;
1224                 case Opt_offgrpjquota:
1225                         qtype = GRPQUOTA;
1226 clear_qf_name:
1227                         if ((sb_any_quota_enabled(sb) ||
1228                              sb_any_quota_suspended(sb)) &&
1229                             sbi->s_qf_names[qtype]) {
1230                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1231                                         "journaled quota options when "
1232                                         "quota turned on.\n");
1233                                 return 0;
1234                         }
1235                         /*
1236                          * The space will be released later when all options
1237                          * are confirmed to be correct
1238                          */
1239                         sbi->s_qf_names[qtype] = NULL;
1240                         break;
1241                 case Opt_jqfmt_vfsold:
1242                         qfmt = QFMT_VFS_OLD;
1243                         goto set_qf_format;
1244                 case Opt_jqfmt_vfsv0:
1245                         qfmt = QFMT_VFS_V0;
1246 set_qf_format:
1247                         if ((sb_any_quota_enabled(sb) ||
1248                              sb_any_quota_suspended(sb)) &&
1249                             sbi->s_jquota_fmt != qfmt) {
1250                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1251                                         "journaled quota options when "
1252                                         "quota turned on.\n");
1253                                 return 0;
1254                         }
1255                         sbi->s_jquota_fmt = qfmt;
1256                         break;
1257                 case Opt_quota:
1258                 case Opt_usrquota:
1259                         set_opt(sbi->s_mount_opt, QUOTA);
1260                         set_opt(sbi->s_mount_opt, USRQUOTA);
1261                         break;
1262                 case Opt_grpquota:
1263                         set_opt(sbi->s_mount_opt, QUOTA);
1264                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1265                         break;
1266                 case Opt_noquota:
1267                         if (sb_any_quota_enabled(sb)) {
1268                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1269                                         "options when quota turned on.\n");
1270                                 return 0;
1271                         }
1272                         clear_opt(sbi->s_mount_opt, QUOTA);
1273                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1274                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1275                         break;
1276 #else
1277                 case Opt_quota:
1278                 case Opt_usrquota:
1279                 case Opt_grpquota:
1280                         printk(KERN_ERR
1281                                 "EXT4-fs: quota options not supported.\n");
1282                         break;
1283                 case Opt_usrjquota:
1284                 case Opt_grpjquota:
1285                 case Opt_offusrjquota:
1286                 case Opt_offgrpjquota:
1287                 case Opt_jqfmt_vfsold:
1288                 case Opt_jqfmt_vfsv0:
1289                         printk(KERN_ERR
1290                                 "EXT4-fs: journaled quota options not "
1291                                 "supported.\n");
1292                         break;
1293                 case Opt_noquota:
1294                         break;
1295 #endif
1296                 case Opt_abort:
1297                         set_opt(sbi->s_mount_opt, ABORT);
1298                         break;
1299                 case Opt_barrier:
1300                         if (match_int(&args[0], &option))
1301                                 return 0;
1302                         if (option)
1303                                 set_opt(sbi->s_mount_opt, BARRIER);
1304                         else
1305                                 clear_opt(sbi->s_mount_opt, BARRIER);
1306                         break;
1307                 case Opt_ignore:
1308                         break;
1309                 case Opt_resize:
1310                         if (!is_remount) {
1311                                 printk("EXT4-fs: resize option only available "
1312                                         "for remount\n");
1313                                 return 0;
1314                         }
1315                         if (match_int(&args[0], &option) != 0)
1316                                 return 0;
1317                         *n_blocks_count = option;
1318                         break;
1319                 case Opt_nobh:
1320                         set_opt(sbi->s_mount_opt, NOBH);
1321                         break;
1322                 case Opt_bh:
1323                         clear_opt(sbi->s_mount_opt, NOBH);
1324                         break;
1325                 case Opt_extents:
1326                         set_opt (sbi->s_mount_opt, EXTENTS);
1327                         break;
1328                 case Opt_noextents:
1329                         clear_opt (sbi->s_mount_opt, EXTENTS);
1330                         break;
1331                 case Opt_i_version:
1332                         set_opt(sbi->s_mount_opt, I_VERSION);
1333                         sb->s_flags |= MS_I_VERSION;
1334                         break;
1335                 case Opt_nodelalloc:
1336                         clear_opt(sbi->s_mount_opt, DELALLOC);
1337                         break;
1338                 case Opt_mballoc:
1339                         set_opt(sbi->s_mount_opt, MBALLOC);
1340                         break;
1341                 case Opt_nomballoc:
1342                         clear_opt(sbi->s_mount_opt, MBALLOC);
1343                         break;
1344                 case Opt_stripe:
1345                         if (match_int(&args[0], &option))
1346                                 return 0;
1347                         if (option < 0)
1348                                 return 0;
1349                         sbi->s_stripe = option;
1350                         break;
1351                 case Opt_delalloc:
1352                         set_opt(sbi->s_mount_opt, DELALLOC);
1353                         break;
1354                 default:
1355                         printk (KERN_ERR
1356                                 "EXT4-fs: Unrecognized mount option \"%s\" "
1357                                 "or missing value\n", p);
1358                         return 0;
1359                 }
1360         }
1361 #ifdef CONFIG_QUOTA
1362         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1363                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1364                      sbi->s_qf_names[USRQUOTA])
1365                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1366
1367                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1368                      sbi->s_qf_names[GRPQUOTA])
1369                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1370
1371                 if ((sbi->s_qf_names[USRQUOTA] &&
1372                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1373                     (sbi->s_qf_names[GRPQUOTA] &&
1374                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1375                         printk(KERN_ERR "EXT4-fs: old and new quota "
1376                                         "format mixing.\n");
1377                         return 0;
1378                 }
1379
1380                 if (!sbi->s_jquota_fmt) {
1381                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1382                                         "not specified.\n");
1383                         return 0;
1384                 }
1385         } else {
1386                 if (sbi->s_jquota_fmt) {
1387                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1388                                         "specified with no journaling "
1389                                         "enabled.\n");
1390                         return 0;
1391                 }
1392         }
1393 #endif
1394         return 1;
1395 }
1396
1397 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1398                             int read_only)
1399 {
1400         struct ext4_sb_info *sbi = EXT4_SB(sb);
1401         int res = 0;
1402
1403         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1404                 printk (KERN_ERR "EXT4-fs warning: revision level too high, "
1405                         "forcing read-only mode\n");
1406                 res = MS_RDONLY;
1407         }
1408         if (read_only)
1409                 return res;
1410         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1411                 printk (KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1412                         "running e2fsck is recommended\n");
1413         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1414                 printk (KERN_WARNING
1415                         "EXT4-fs warning: mounting fs with errors, "
1416                         "running e2fsck is recommended\n");
1417         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1418                  le16_to_cpu(es->s_mnt_count) >=
1419                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1420                 printk (KERN_WARNING
1421                         "EXT4-fs warning: maximal mount count reached, "
1422                         "running e2fsck is recommended\n");
1423         else if (le32_to_cpu(es->s_checkinterval) &&
1424                 (le32_to_cpu(es->s_lastcheck) +
1425                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1426                 printk (KERN_WARNING
1427                         "EXT4-fs warning: checktime reached, "
1428                         "running e2fsck is recommended\n");
1429 #if 0
1430                 /* @@@ We _will_ want to clear the valid bit if we find
1431                  * inconsistencies, to force a fsck at reboot.  But for
1432                  * a plain journaled filesystem we can keep it set as
1433                  * valid forever! :)
1434                  */
1435         es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1436 #endif
1437         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1438                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1439         le16_add_cpu(&es->s_mnt_count, 1);
1440         es->s_mtime = cpu_to_le32(get_seconds());
1441         ext4_update_dynamic_rev(sb);
1442         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1443
1444         ext4_commit_super(sb, es, 1);
1445         if (test_opt(sb, DEBUG))
1446                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1447                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1448                         sb->s_blocksize,
1449                         sbi->s_groups_count,
1450                         EXT4_BLOCKS_PER_GROUP(sb),
1451                         EXT4_INODES_PER_GROUP(sb),
1452                         sbi->s_mount_opt);
1453
1454         printk(KERN_INFO "EXT4 FS on %s, ", sb->s_id);
1455         if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
1456                 char b[BDEVNAME_SIZE];
1457
1458                 printk("external journal on %s\n",
1459                         bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
1460         } else {
1461                 printk("internal journal\n");
1462         }
1463         return res;
1464 }
1465
1466 static int ext4_fill_flex_info(struct super_block *sb)
1467 {
1468         struct ext4_sb_info *sbi = EXT4_SB(sb);
1469         struct ext4_group_desc *gdp = NULL;
1470         struct buffer_head *bh;
1471         ext4_group_t flex_group_count;
1472         ext4_group_t flex_group;
1473         int groups_per_flex = 0;
1474         __u64 block_bitmap = 0;
1475         int i;
1476
1477         if (!sbi->s_es->s_log_groups_per_flex) {
1478                 sbi->s_log_groups_per_flex = 0;
1479                 return 1;
1480         }
1481
1482         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1483         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1484
1485         flex_group_count = (sbi->s_groups_count + groups_per_flex - 1) /
1486                 groups_per_flex;
1487         sbi->s_flex_groups = kmalloc(flex_group_count *
1488                                      sizeof(struct flex_groups), GFP_KERNEL);
1489         if (sbi->s_flex_groups == NULL) {
1490                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
1491                 goto failed;
1492         }
1493         memset(sbi->s_flex_groups, 0, flex_group_count *
1494                sizeof(struct flex_groups));
1495
1496         gdp = ext4_get_group_desc(sb, 1, &bh);
1497         block_bitmap = ext4_block_bitmap(sb, gdp) - 1;
1498
1499         for (i = 0; i < sbi->s_groups_count; i++) {
1500                 gdp = ext4_get_group_desc(sb, i, &bh);
1501
1502                 flex_group = ext4_flex_group(sbi, i);
1503                 sbi->s_flex_groups[flex_group].free_inodes +=
1504                         le16_to_cpu(gdp->bg_free_inodes_count);
1505                 sbi->s_flex_groups[flex_group].free_blocks +=
1506                         le16_to_cpu(gdp->bg_free_blocks_count);
1507         }
1508
1509         return 1;
1510 failed:
1511         return 0;
1512 }
1513
1514 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1515                             struct ext4_group_desc *gdp)
1516 {
1517         __u16 crc = 0;
1518
1519         if (sbi->s_es->s_feature_ro_compat &
1520             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1521                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1522                 __le32 le_group = cpu_to_le32(block_group);
1523
1524                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1525                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1526                 crc = crc16(crc, (__u8 *)gdp, offset);
1527                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1528                 /* for checksum of struct ext4_group_desc do the rest...*/
1529                 if ((sbi->s_es->s_feature_incompat &
1530                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1531                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1532                         crc = crc16(crc, (__u8 *)gdp + offset,
1533                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1534                                         offset);
1535         }
1536
1537         return cpu_to_le16(crc);
1538 }
1539
1540 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1541                                 struct ext4_group_desc *gdp)
1542 {
1543         if ((sbi->s_es->s_feature_ro_compat &
1544              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1545             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1546                 return 0;
1547
1548         return 1;
1549 }
1550
1551 /* Called at mount-time, super-block is locked */
1552 static int ext4_check_descriptors(struct super_block *sb)
1553 {
1554         struct ext4_sb_info *sbi = EXT4_SB(sb);
1555         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1556         ext4_fsblk_t last_block;
1557         ext4_fsblk_t block_bitmap;
1558         ext4_fsblk_t inode_bitmap;
1559         ext4_fsblk_t inode_table;
1560         int flexbg_flag = 0;
1561         ext4_group_t i;
1562
1563         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1564                 flexbg_flag = 1;
1565
1566         ext4_debug ("Checking group descriptors");
1567
1568         for (i = 0; i < sbi->s_groups_count; i++) {
1569                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1570
1571                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1572                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1573                 else
1574                         last_block = first_block +
1575                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1576
1577                 block_bitmap = ext4_block_bitmap(sb, gdp);
1578                 if (block_bitmap < first_block || block_bitmap > last_block)
1579                 {
1580                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1581                                "Block bitmap for group %lu not in group "
1582                                "(block %llu)!", i, block_bitmap);
1583                         return 0;
1584                 }
1585                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1586                 if (inode_bitmap < first_block || inode_bitmap > last_block)
1587                 {
1588                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1589                                "Inode bitmap for group %lu not in group "
1590                                "(block %llu)!", i, inode_bitmap);
1591                         return 0;
1592                 }
1593                 inode_table = ext4_inode_table(sb, gdp);
1594                 if (inode_table < first_block ||
1595                     inode_table + sbi->s_itb_per_group - 1 > last_block)
1596                 {
1597                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1598                                "Inode table for group %lu not in group "
1599                                "(block %llu)!", i, inode_table);
1600                         return 0;
1601                 }
1602                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1603                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1604                                "Checksum for group %lu failed (%u!=%u)\n",
1605                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1606                                gdp)), le16_to_cpu(gdp->bg_checksum));
1607                         return 0;
1608                 }
1609                 if (!flexbg_flag)
1610                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1611         }
1612
1613         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1614         sbi->s_es->s_free_inodes_count=cpu_to_le32(ext4_count_free_inodes(sb));
1615         return 1;
1616 }
1617
1618 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1619  * the superblock) which were deleted from all directories, but held open by
1620  * a process at the time of a crash.  We walk the list and try to delete these
1621  * inodes at recovery time (only with a read-write filesystem).
1622  *
1623  * In order to keep the orphan inode chain consistent during traversal (in
1624  * case of crash during recovery), we link each inode into the superblock
1625  * orphan list_head and handle it the same way as an inode deletion during
1626  * normal operation (which journals the operations for us).
1627  *
1628  * We only do an iget() and an iput() on each inode, which is very safe if we
1629  * accidentally point at an in-use or already deleted inode.  The worst that
1630  * can happen in this case is that we get a "bit already cleared" message from
1631  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1632  * e2fsck was run on this filesystem, and it must have already done the orphan
1633  * inode cleanup for us, so we can safely abort without any further action.
1634  */
1635 static void ext4_orphan_cleanup (struct super_block * sb,
1636                                  struct ext4_super_block * es)
1637 {
1638         unsigned int s_flags = sb->s_flags;
1639         int nr_orphans = 0, nr_truncates = 0;
1640 #ifdef CONFIG_QUOTA
1641         int i;
1642 #endif
1643         if (!es->s_last_orphan) {
1644                 jbd_debug(4, "no orphan inodes to clean up\n");
1645                 return;
1646         }
1647
1648         if (bdev_read_only(sb->s_bdev)) {
1649                 printk(KERN_ERR "EXT4-fs: write access "
1650                         "unavailable, skipping orphan cleanup.\n");
1651                 return;
1652         }
1653
1654         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1655                 if (es->s_last_orphan)
1656                         jbd_debug(1, "Errors on filesystem, "
1657                                   "clearing orphan list.\n");
1658                 es->s_last_orphan = 0;
1659                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1660                 return;
1661         }
1662
1663         if (s_flags & MS_RDONLY) {
1664                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1665                        sb->s_id);
1666                 sb->s_flags &= ~MS_RDONLY;
1667         }
1668 #ifdef CONFIG_QUOTA
1669         /* Needed for iput() to work correctly and not trash data */
1670         sb->s_flags |= MS_ACTIVE;
1671         /* Turn on quotas so that they are updated correctly */
1672         for (i = 0; i < MAXQUOTAS; i++) {
1673                 if (EXT4_SB(sb)->s_qf_names[i]) {
1674                         int ret = ext4_quota_on_mount(sb, i);
1675                         if (ret < 0)
1676                                 printk(KERN_ERR
1677                                         "EXT4-fs: Cannot turn on journaled "
1678                                         "quota: error %d\n", ret);
1679                 }
1680         }
1681 #endif
1682
1683         while (es->s_last_orphan) {
1684                 struct inode *inode;
1685
1686                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1687                 if (IS_ERR(inode)) {
1688                         es->s_last_orphan = 0;
1689                         break;
1690                 }
1691
1692                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1693                 DQUOT_INIT(inode);
1694                 if (inode->i_nlink) {
1695                         printk(KERN_DEBUG
1696                                 "%s: truncating inode %lu to %Ld bytes\n",
1697                                 __func__, inode->i_ino, inode->i_size);
1698                         jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
1699                                   inode->i_ino, inode->i_size);
1700                         ext4_truncate(inode);
1701                         nr_truncates++;
1702                 } else {
1703                         printk(KERN_DEBUG
1704                                 "%s: deleting unreferenced inode %lu\n",
1705                                 __func__, inode->i_ino);
1706                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1707                                   inode->i_ino);
1708                         nr_orphans++;
1709                 }
1710                 iput(inode);  /* The delete magic happens here! */
1711         }
1712
1713 #define PLURAL(x) (x), ((x)==1) ? "" : "s"
1714
1715         if (nr_orphans)
1716                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1717                        sb->s_id, PLURAL(nr_orphans));
1718         if (nr_truncates)
1719                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1720                        sb->s_id, PLURAL(nr_truncates));
1721 #ifdef CONFIG_QUOTA
1722         /* Turn quotas off */
1723         for (i = 0; i < MAXQUOTAS; i++) {
1724                 if (sb_dqopt(sb)->files[i])
1725                         vfs_quota_off(sb, i, 0);
1726         }
1727 #endif
1728         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1729 }
1730 /*
1731  * Maximal extent format file size.
1732  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1733  * extent format containers, within a sector_t, and within i_blocks
1734  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1735  * so that won't be a limiting factor.
1736  *
1737  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1738  */
1739 static loff_t ext4_max_size(int blkbits)
1740 {
1741         loff_t res;
1742         loff_t upper_limit = MAX_LFS_FILESIZE;
1743
1744         /* small i_blocks in vfs inode? */
1745         if (sizeof(blkcnt_t) < sizeof(u64)) {
1746                 /*
1747                  * CONFIG_LSF is not enabled implies the inode
1748                  * i_block represent total blocks in 512 bytes
1749                  * 32 == size of vfs inode i_blocks * 8
1750                  */
1751                 upper_limit = (1LL << 32) - 1;
1752
1753                 /* total blocks in file system block size */
1754                 upper_limit >>= (blkbits - 9);
1755                 upper_limit <<= blkbits;
1756         }
1757
1758         /* 32-bit extent-start container, ee_block */
1759         res = 1LL << 32;
1760         res <<= blkbits;
1761         res -= 1;
1762
1763         /* Sanity check against vm- & vfs- imposed limits */
1764         if (res > upper_limit)
1765                 res = upper_limit;
1766
1767         return res;
1768 }
1769
1770 /*
1771  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1772  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1773  * We need to be 1 filesystem block less than the 2^48 sector limit.
1774  */
1775 static loff_t ext4_max_bitmap_size(int bits)
1776 {
1777         loff_t res = EXT4_NDIR_BLOCKS;
1778         int meta_blocks;
1779         loff_t upper_limit;
1780         /* This is calculated to be the largest file size for a
1781          * dense, bitmapped file such that the total number of
1782          * sectors in the file, including data and all indirect blocks,
1783          * does not exceed 2^48 -1
1784          * __u32 i_blocks_lo and _u16 i_blocks_high representing the
1785          * total number of  512 bytes blocks of the file
1786          */
1787
1788         if (sizeof(blkcnt_t) < sizeof(u64)) {
1789                 /*
1790                  * CONFIG_LSF is not enabled implies the inode
1791                  * i_block represent total blocks in 512 bytes
1792                  * 32 == size of vfs inode i_blocks * 8
1793                  */
1794                 upper_limit = (1LL << 32) - 1;
1795
1796                 /* total blocks in file system block size */
1797                 upper_limit >>= (bits - 9);
1798
1799         } else {
1800                 /*
1801                  * We use 48 bit ext4_inode i_blocks
1802                  * With EXT4_HUGE_FILE_FL set the i_blocks
1803                  * represent total number of blocks in
1804                  * file system block size
1805                  */
1806                 upper_limit = (1LL << 48) - 1;
1807
1808         }
1809
1810         /* indirect blocks */
1811         meta_blocks = 1;
1812         /* double indirect blocks */
1813         meta_blocks += 1 + (1LL << (bits-2));
1814         /* tripple indirect blocks */
1815         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
1816
1817         upper_limit -= meta_blocks;
1818         upper_limit <<= bits;
1819
1820         res += 1LL << (bits-2);
1821         res += 1LL << (2*(bits-2));
1822         res += 1LL << (3*(bits-2));
1823         res <<= bits;
1824         if (res > upper_limit)
1825                 res = upper_limit;
1826
1827         if (res > MAX_LFS_FILESIZE)
1828                 res = MAX_LFS_FILESIZE;
1829
1830         return res;
1831 }
1832
1833 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1834                                 ext4_fsblk_t logical_sb_block, int nr)
1835 {
1836         struct ext4_sb_info *sbi = EXT4_SB(sb);
1837         ext4_group_t bg, first_meta_bg;
1838         int has_super = 0;
1839
1840         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1841
1842         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1843             nr < first_meta_bg)
1844                 return logical_sb_block + nr + 1;
1845         bg = sbi->s_desc_per_block * nr;
1846         if (ext4_bg_has_super(sb, bg))
1847                 has_super = 1;
1848         return (has_super + ext4_group_first_block_no(sb, bg));
1849 }
1850
1851 /**
1852  * ext4_get_stripe_size: Get the stripe size.
1853  * @sbi: In memory super block info
1854  *
1855  * If we have specified it via mount option, then
1856  * use the mount option value. If the value specified at mount time is
1857  * greater than the blocks per group use the super block value.
1858  * If the super block value is greater than blocks per group return 0.
1859  * Allocator needs it be less than blocks per group.
1860  *
1861  */
1862 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
1863 {
1864         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
1865         unsigned long stripe_width =
1866                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
1867
1868         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
1869                 return sbi->s_stripe;
1870
1871         if (stripe_width <= sbi->s_blocks_per_group)
1872                 return stripe_width;
1873
1874         if (stride <= sbi->s_blocks_per_group)
1875                 return stride;
1876
1877         return 0;
1878 }
1879
1880 static int ext4_fill_super (struct super_block *sb, void *data, int silent)
1881                                 __releases(kernel_lock)
1882                                 __acquires(kernel_lock)
1883
1884 {
1885         struct buffer_head * bh;
1886         struct ext4_super_block *es = NULL;
1887         struct ext4_sb_info *sbi;
1888         ext4_fsblk_t block;
1889         ext4_fsblk_t sb_block = get_sb_block(&data);
1890         ext4_fsblk_t logical_sb_block;
1891         unsigned long offset = 0;
1892         unsigned int journal_inum = 0;
1893         unsigned long journal_devnum = 0;
1894         unsigned long def_mount_opts;
1895         struct inode *root;
1896         int ret = -EINVAL;
1897         int blocksize;
1898         int db_count;
1899         int i;
1900         int needs_recovery;
1901         __le32 features;
1902         __u64 blocks_count;
1903         int err;
1904
1905         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1906         if (!sbi)
1907                 return -ENOMEM;
1908         sb->s_fs_info = sbi;
1909         sbi->s_mount_opt = 0;
1910         sbi->s_resuid = EXT4_DEF_RESUID;
1911         sbi->s_resgid = EXT4_DEF_RESGID;
1912         sbi->s_sb_block = sb_block;
1913
1914         unlock_kernel();
1915
1916         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1917         if (!blocksize) {
1918                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1919                 goto out_fail;
1920         }
1921
1922         /*
1923          * The ext4 superblock will not be buffer aligned for other than 1kB
1924          * block sizes.  We need to calculate the offset from buffer start.
1925          */
1926         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1927                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1928                 offset = do_div(logical_sb_block, blocksize);
1929         } else {
1930                 logical_sb_block = sb_block;
1931         }
1932
1933         if (!(bh = sb_bread(sb, logical_sb_block))) {
1934                 printk (KERN_ERR "EXT4-fs: unable to read superblock\n");
1935                 goto out_fail;
1936         }
1937         /*
1938          * Note: s_es must be initialized as soon as possible because
1939          *       some ext4 macro-instructions depend on its value
1940          */
1941         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1942         sbi->s_es = es;
1943         sb->s_magic = le16_to_cpu(es->s_magic);
1944         if (sb->s_magic != EXT4_SUPER_MAGIC)
1945                 goto cantfind_ext4;
1946
1947         /* Set defaults before we parse the mount options */
1948         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1949         if (def_mount_opts & EXT4_DEFM_DEBUG)
1950                 set_opt(sbi->s_mount_opt, DEBUG);
1951         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1952                 set_opt(sbi->s_mount_opt, GRPID);
1953         if (def_mount_opts & EXT4_DEFM_UID16)
1954                 set_opt(sbi->s_mount_opt, NO_UID32);
1955 #ifdef CONFIG_EXT4DEV_FS_XATTR
1956         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1957                 set_opt(sbi->s_mount_opt, XATTR_USER);
1958 #endif
1959 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1960         if (def_mount_opts & EXT4_DEFM_ACL)
1961                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1962 #endif
1963         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1964                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1965         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1966                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1967         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1968                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
1969
1970         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
1971                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1972         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
1973                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
1974         else
1975                 set_opt(sbi->s_mount_opt, ERRORS_RO);
1976
1977         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
1978         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
1979
1980         set_opt(sbi->s_mount_opt, RESERVATION);
1981         set_opt(sbi->s_mount_opt, BARRIER);
1982
1983         /*
1984          * turn on extents feature by default in ext4 filesystem
1985          * User -o noextents to turn it off
1986          */
1987         set_opt(sbi->s_mount_opt, EXTENTS);
1988         /*
1989          * turn on mballoc feature by default in ext4 filesystem
1990          * User -o nomballoc to turn it off
1991          */
1992         set_opt(sbi->s_mount_opt, MBALLOC);
1993
1994         /*
1995          * enable delayed allocation by default
1996          * Use -o nodelalloc to turn it off
1997          */
1998         set_opt(sbi->s_mount_opt, DELALLOC);
1999
2000
2001         if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
2002                             NULL, 0))
2003                 goto failed_mount;
2004
2005         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2006                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2007
2008         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2009             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2010              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2011              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2012                 printk(KERN_WARNING
2013                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2014                        "running e2fsck is recommended\n");
2015
2016         /*
2017          * Since ext4 is still considered development code, we require
2018          * that the TEST_FILESYS flag in s->flags be set.
2019          */
2020         if (!(le32_to_cpu(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)) {
2021                 printk(KERN_WARNING "EXT4-fs: %s: not marked "
2022                        "OK to use with test code.\n", sb->s_id);
2023                 goto failed_mount;
2024         }
2025
2026         /*
2027          * Check feature flags regardless of the revision level, since we
2028          * previously didn't change the revision level when setting the flags,
2029          * so there is a chance incompat flags are set on a rev 0 filesystem.
2030          */
2031         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2032         if (features) {
2033                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2034                        "unsupported optional features (%x).\n",
2035                        sb->s_id, le32_to_cpu(features));
2036                 goto failed_mount;
2037         }
2038         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2039         if (!(sb->s_flags & MS_RDONLY) && features) {
2040                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2041                        "unsupported optional features (%x).\n",
2042                        sb->s_id, le32_to_cpu(features));
2043                 goto failed_mount;
2044         }
2045         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2046                 /*
2047                  * Large file size enabled file system can only be
2048                  * mount if kernel is build with CONFIG_LSF
2049                  */
2050                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2051                                 !(sb->s_flags & MS_RDONLY)) {
2052                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2053                                         "files cannot be mounted read-write "
2054                                         "without CONFIG_LSF.\n", sb->s_id);
2055                         goto failed_mount;
2056                 }
2057         }
2058         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2059
2060         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2061             blocksize > EXT4_MAX_BLOCK_SIZE) {
2062                 printk(KERN_ERR
2063                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2064                        blocksize, sb->s_id);
2065                 goto failed_mount;
2066         }
2067
2068         if (sb->s_blocksize != blocksize) {
2069
2070                 /* Validate the filesystem blocksize */
2071                 if (!sb_set_blocksize(sb, blocksize)) {
2072                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2073                                         blocksize);
2074                         goto failed_mount;
2075                 }
2076
2077                 brelse (bh);
2078                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2079                 offset = do_div(logical_sb_block, blocksize);
2080                 bh = sb_bread(sb, logical_sb_block);
2081                 if (!bh) {
2082                         printk(KERN_ERR
2083                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2084                         goto failed_mount;
2085                 }
2086                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2087                 sbi->s_es = es;
2088                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2089                         printk (KERN_ERR
2090                                 "EXT4-fs: Magic mismatch, very weird !\n");
2091                         goto failed_mount;
2092                 }
2093         }
2094
2095         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits);
2096         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
2097
2098         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2099                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2100                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2101         } else {
2102                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2103                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2104                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2105                     (!is_power_of_2(sbi->s_inode_size)) ||
2106                     (sbi->s_inode_size > blocksize)) {
2107                         printk (KERN_ERR
2108                                 "EXT4-fs: unsupported inode size: %d\n",
2109                                 sbi->s_inode_size);
2110                         goto failed_mount;
2111                 }
2112                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2113                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2114         }
2115         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2116         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2117                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2118                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2119                     !is_power_of_2(sbi->s_desc_size)) {
2120                         printk(KERN_ERR
2121                                "EXT4-fs: unsupported descriptor size %lu\n",
2122                                sbi->s_desc_size);
2123                         goto failed_mount;
2124                 }
2125         } else
2126                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2127         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2128         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2129         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2130                 goto cantfind_ext4;
2131         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2132         if (sbi->s_inodes_per_block == 0)
2133                 goto cantfind_ext4;
2134         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2135                                         sbi->s_inodes_per_block;
2136         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2137         sbi->s_sbh = bh;
2138         sbi->s_mount_state = le16_to_cpu(es->s_state);
2139         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2140         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2141         for (i=0; i < 4; i++)
2142                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2143         sbi->s_def_hash_version = es->s_def_hash_version;
2144
2145         if (sbi->s_blocks_per_group > blocksize * 8) {
2146                 printk (KERN_ERR
2147                         "EXT4-fs: #blocks per group too big: %lu\n",
2148                         sbi->s_blocks_per_group);
2149                 goto failed_mount;
2150         }
2151         if (sbi->s_inodes_per_group > blocksize * 8) {
2152                 printk (KERN_ERR
2153                         "EXT4-fs: #inodes per group too big: %lu\n",
2154                         sbi->s_inodes_per_group);
2155                 goto failed_mount;
2156         }
2157
2158         if (ext4_blocks_count(es) >
2159                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2160                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2161                         " too large to mount safely\n", sb->s_id);
2162                 if (sizeof(sector_t) < 8)
2163                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2164                                         "enabled\n");
2165                 goto failed_mount;
2166         }
2167
2168         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2169                 goto cantfind_ext4;
2170
2171         /* ensure blocks_count calculation below doesn't sign-extend */
2172         if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
2173             le32_to_cpu(es->s_first_data_block) + 1) {
2174                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
2175                        "first data block %u, blocks per group %lu\n",
2176                         ext4_blocks_count(es),
2177                         le32_to_cpu(es->s_first_data_block),
2178                         EXT4_BLOCKS_PER_GROUP(sb));
2179                 goto failed_mount;
2180         }
2181         blocks_count = (ext4_blocks_count(es) -
2182                         le32_to_cpu(es->s_first_data_block) +
2183                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2184         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2185         sbi->s_groups_count = blocks_count;
2186         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2187                    EXT4_DESC_PER_BLOCK(sb);
2188         sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
2189                                     GFP_KERNEL);
2190         if (sbi->s_group_desc == NULL) {
2191                 printk (KERN_ERR "EXT4-fs: not enough memory\n");
2192                 goto failed_mount;
2193         }
2194
2195         bgl_lock_init(&sbi->s_blockgroup_lock);
2196
2197         for (i = 0; i < db_count; i++) {
2198                 block = descriptor_loc(sb, logical_sb_block, i);
2199                 sbi->s_group_desc[i] = sb_bread(sb, block);
2200                 if (!sbi->s_group_desc[i]) {
2201                         printk (KERN_ERR "EXT4-fs: "
2202                                 "can't read group descriptor %d\n", i);
2203                         db_count = i;
2204                         goto failed_mount2;
2205                 }
2206         }
2207         if (!ext4_check_descriptors (sb)) {
2208                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2209                 goto failed_mount2;
2210         }
2211         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2212                 if (!ext4_fill_flex_info(sb)) {
2213                         printk(KERN_ERR
2214                                "EXT4-fs: unable to initialize "
2215                                "flex_bg meta info!\n");
2216                         goto failed_mount2;
2217                 }
2218
2219         sbi->s_gdb_count = db_count;
2220         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2221         spin_lock_init(&sbi->s_next_gen_lock);
2222
2223         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2224                         ext4_count_free_blocks(sb));
2225         if (!err) {
2226                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2227                                 ext4_count_free_inodes(sb));
2228         }
2229         if (!err) {
2230                 err = percpu_counter_init(&sbi->s_dirs_counter,
2231                                 ext4_count_dirs(sb));
2232         }
2233         if (err) {
2234                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2235                 goto failed_mount3;
2236         }
2237
2238         /* per fileystem reservation list head & lock */
2239         spin_lock_init(&sbi->s_rsv_window_lock);
2240         sbi->s_rsv_window_root = RB_ROOT;
2241         /* Add a single, static dummy reservation to the start of the
2242          * reservation window list --- it gives us a placeholder for
2243          * append-at-start-of-list which makes the allocation logic
2244          * _much_ simpler. */
2245         sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2246         sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2247         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
2248         sbi->s_rsv_window_head.rsv_goal_size = 0;
2249         ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
2250
2251         sbi->s_stripe = ext4_get_stripe_size(sbi);
2252
2253         /*
2254          * set up enough so that it can read an inode
2255          */
2256         sb->s_op = &ext4_sops;
2257         sb->s_export_op = &ext4_export_ops;
2258         sb->s_xattr = ext4_xattr_handlers;
2259 #ifdef CONFIG_QUOTA
2260         sb->s_qcop = &ext4_qctl_operations;
2261         sb->dq_op = &ext4_quota_operations;
2262 #endif
2263         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2264
2265         sb->s_root = NULL;
2266
2267         needs_recovery = (es->s_last_orphan != 0 ||
2268                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2269                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2270
2271         /*
2272          * The first inode we look at is the journal inode.  Don't try
2273          * root first: it may be modified in the journal!
2274          */
2275         if (!test_opt(sb, NOLOAD) &&
2276             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2277                 if (ext4_load_journal(sb, es, journal_devnum))
2278                         goto failed_mount3;
2279                 if (!(sb->s_flags & MS_RDONLY) &&
2280                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2281                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2282                                "ext4_fill_super: Journal transaction "
2283                                "%u is corrupt\n", sb->s_id,
2284                                EXT4_SB(sb)->s_journal->j_failed_commit);
2285                         if (test_opt (sb, ERRORS_RO)) {
2286                                 printk (KERN_CRIT
2287                                         "Mounting filesystem read-only\n");
2288                                 sb->s_flags |= MS_RDONLY;
2289                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2290                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2291                         }
2292                         if (test_opt(sb, ERRORS_PANIC)) {
2293                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2294                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2295                                 ext4_commit_super(sb, es, 1);
2296                                 printk(KERN_CRIT
2297                                        "EXT4-fs (device %s): mount failed\n",
2298                                       sb->s_id);
2299                                 goto failed_mount4;
2300                         }
2301                 }
2302         } else if (journal_inum) {
2303                 if (ext4_create_journal(sb, es, journal_inum))
2304                         goto failed_mount3;
2305         } else {
2306                 if (!silent)
2307                         printk (KERN_ERR
2308                                 "ext4: No journal on filesystem on %s\n",
2309                                 sb->s_id);
2310                 goto failed_mount3;
2311         }
2312
2313         if (ext4_blocks_count(es) > 0xffffffffULL &&
2314             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2315                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2316                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
2317                 goto failed_mount4;
2318         }
2319
2320         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2321                 jbd2_journal_set_features(sbi->s_journal,
2322                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2323                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2324         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2325                 jbd2_journal_set_features(sbi->s_journal,
2326                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2327                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2328                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2329         } else {
2330                 jbd2_journal_clear_features(sbi->s_journal,
2331                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2332                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2333         }
2334
2335         /* We have now updated the journal if required, so we can
2336          * validate the data journaling mode. */
2337         switch (test_opt(sb, DATA_FLAGS)) {
2338         case 0:
2339                 /* No mode set, assume a default based on the journal
2340                  * capabilities: ORDERED_DATA if the journal can
2341                  * cope, else JOURNAL_DATA
2342                  */
2343                 if (jbd2_journal_check_available_features
2344                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2345                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2346                 else
2347                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2348                 break;
2349
2350         case EXT4_MOUNT_ORDERED_DATA:
2351         case EXT4_MOUNT_WRITEBACK_DATA:
2352                 if (!jbd2_journal_check_available_features
2353                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2354                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2355                                "requested data journaling mode\n");
2356                         goto failed_mount4;
2357                 }
2358         default:
2359                 break;
2360         }
2361
2362         if (test_opt(sb, NOBH)) {
2363                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2364                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2365                                 "its supported only with writeback mode\n");
2366                         clear_opt(sbi->s_mount_opt, NOBH);
2367                 }
2368         }
2369         /*
2370          * The jbd2_journal_load will have done any necessary log recovery,
2371          * so we can safely mount the rest of the filesystem now.
2372          */
2373
2374         root = ext4_iget(sb, EXT4_ROOT_INO);
2375         if (IS_ERR(root)) {
2376                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2377                 ret = PTR_ERR(root);
2378                 goto failed_mount4;
2379         }
2380         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2381                 iput(root);
2382                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2383                 goto failed_mount4;
2384         }
2385         sb->s_root = d_alloc_root(root);
2386         if (!sb->s_root) {
2387                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2388                 iput(root);
2389                 ret = -ENOMEM;
2390                 goto failed_mount4;
2391         }
2392
2393         ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY);
2394
2395         /* determine the minimum size of new large inodes, if present */
2396         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2397                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2398                                                      EXT4_GOOD_OLD_INODE_SIZE;
2399                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2400                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2401                         if (sbi->s_want_extra_isize <
2402                             le16_to_cpu(es->s_want_extra_isize))
2403                                 sbi->s_want_extra_isize =
2404                                         le16_to_cpu(es->s_want_extra_isize);
2405                         if (sbi->s_want_extra_isize <
2406                             le16_to_cpu(es->s_min_extra_isize))
2407                                 sbi->s_want_extra_isize =
2408                                         le16_to_cpu(es->s_min_extra_isize);
2409                 }
2410         }
2411         /* Check if enough inode space is available */
2412         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2413                                                         sbi->s_inode_size) {
2414                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2415                                                        EXT4_GOOD_OLD_INODE_SIZE;
2416                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2417                         "available.\n");
2418         }
2419
2420         /*
2421          * akpm: core read_super() calls in here with the superblock locked.
2422          * That deadlocks, because orphan cleanup needs to lock the superblock
2423          * in numerous places.  Here we just pop the lock - it's relatively
2424          * harmless, because we are now ready to accept write_super() requests,
2425          * and aviro says that's the only reason for hanging onto the
2426          * superblock lock.
2427          */
2428         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2429         ext4_orphan_cleanup(sb, es);
2430         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2431         if (needs_recovery)
2432                 printk (KERN_INFO "EXT4-fs: recovery complete.\n");
2433         ext4_mark_recovery_complete(sb, es);
2434         printk (KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
2435                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
2436                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
2437                 "writeback");
2438
2439         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2440                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2441                                 "requested data journaling mode\n");
2442                 clear_opt(sbi->s_mount_opt, DELALLOC);
2443         } else if (test_opt(sb, DELALLOC))
2444                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2445
2446         ext4_ext_init(sb);
2447         ext4_mb_init(sb, needs_recovery);
2448
2449         lock_kernel();
2450         return 0;
2451
2452 cantfind_ext4:
2453         if (!silent)
2454                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2455                        sb->s_id);
2456         goto failed_mount;
2457
2458 failed_mount4:
2459         jbd2_journal_destroy(sbi->s_journal);
2460         sbi->s_journal = NULL;
2461 failed_mount3:
2462         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2463         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2464         percpu_counter_destroy(&sbi->s_dirs_counter);
2465 failed_mount2:
2466         for (i = 0; i < db_count; i++)
2467                 brelse(sbi->s_group_desc[i]);
2468         kfree(sbi->s_group_desc);
2469 failed_mount:
2470 #ifdef CONFIG_QUOTA
2471         for (i = 0; i < MAXQUOTAS; i++)
2472                 kfree(sbi->s_qf_names[i]);
2473 #endif
2474         ext4_blkdev_remove(sbi);
2475         brelse(bh);
2476 out_fail:
2477         sb->s_fs_info = NULL;
2478         kfree(sbi);
2479         lock_kernel();
2480         return ret;
2481 }
2482
2483 /*
2484  * Setup any per-fs journal parameters now.  We'll do this both on
2485  * initial mount, once the journal has been initialised but before we've
2486  * done any recovery; and again on any subsequent remount.
2487  */
2488 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2489 {
2490         struct ext4_sb_info *sbi = EXT4_SB(sb);
2491
2492         if (sbi->s_commit_interval)
2493                 journal->j_commit_interval = sbi->s_commit_interval;
2494         /* We could also set up an ext4-specific default for the commit
2495          * interval here, but for now we'll just fall back to the jbd
2496          * default. */
2497
2498         spin_lock(&journal->j_state_lock);
2499         if (test_opt(sb, BARRIER))
2500                 journal->j_flags |= JBD2_BARRIER;
2501         else
2502                 journal->j_flags &= ~JBD2_BARRIER;
2503         spin_unlock(&journal->j_state_lock);
2504 }
2505
2506 static journal_t *ext4_get_journal(struct super_block *sb,
2507                                    unsigned int journal_inum)
2508 {
2509         struct inode *journal_inode;
2510         journal_t *journal;
2511
2512         /* First, test for the existence of a valid inode on disk.  Bad
2513          * things happen if we iget() an unused inode, as the subsequent
2514          * iput() will try to delete it. */
2515
2516         journal_inode = ext4_iget(sb, journal_inum);
2517         if (IS_ERR(journal_inode)) {
2518                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2519                 return NULL;
2520         }
2521         if (!journal_inode->i_nlink) {
2522                 make_bad_inode(journal_inode);
2523                 iput(journal_inode);
2524                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2525                 return NULL;
2526         }
2527
2528         jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
2529                   journal_inode, journal_inode->i_size);
2530         if (!S_ISREG(journal_inode->i_mode)) {
2531                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2532                 iput(journal_inode);
2533                 return NULL;
2534         }
2535
2536         journal = jbd2_journal_init_inode(journal_inode);
2537         if (!journal) {
2538                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2539                 iput(journal_inode);
2540                 return NULL;
2541         }
2542         journal->j_private = sb;
2543         ext4_init_journal_params(sb, journal);
2544         return journal;
2545 }
2546
2547 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2548                                        dev_t j_dev)
2549 {
2550         struct buffer_head * bh;
2551         journal_t *journal;
2552         ext4_fsblk_t start;
2553         ext4_fsblk_t len;
2554         int hblock, blocksize;
2555         ext4_fsblk_t sb_block;
2556         unsigned long offset;
2557         struct ext4_super_block * es;
2558         struct block_device *bdev;
2559
2560         bdev = ext4_blkdev_get(j_dev);
2561         if (bdev == NULL)
2562                 return NULL;
2563
2564         if (bd_claim(bdev, sb)) {
2565                 printk(KERN_ERR
2566                         "EXT4: failed to claim external journal device.\n");
2567                 blkdev_put(bdev);
2568                 return NULL;
2569         }
2570
2571         blocksize = sb->s_blocksize;
2572         hblock = bdev_hardsect_size(bdev);
2573         if (blocksize < hblock) {
2574                 printk(KERN_ERR
2575                         "EXT4-fs: blocksize too small for journal device.\n");
2576                 goto out_bdev;
2577         }
2578
2579         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2580         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2581         set_blocksize(bdev, blocksize);
2582         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2583                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2584                        "external journal\n");
2585                 goto out_bdev;
2586         }
2587
2588         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2589         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2590             !(le32_to_cpu(es->s_feature_incompat) &
2591               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2592                 printk(KERN_ERR "EXT4-fs: external journal has "
2593                                         "bad superblock\n");
2594                 brelse(bh);
2595                 goto out_bdev;
2596         }
2597
2598         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2599                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2600                 brelse(bh);
2601                 goto out_bdev;
2602         }
2603
2604         len = ext4_blocks_count(es);
2605         start = sb_block + 1;
2606         brelse(bh);     /* we're done with the superblock */
2607
2608         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2609                                         start, len, blocksize);
2610         if (!journal) {
2611                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2612                 goto out_bdev;
2613         }
2614         journal->j_private = sb;
2615         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2616         wait_on_buffer(journal->j_sb_buffer);
2617         if (!buffer_uptodate(journal->j_sb_buffer)) {
2618                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2619                 goto out_journal;
2620         }
2621         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2622                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2623                                         "user (unsupported) - %d\n",
2624                         be32_to_cpu(journal->j_superblock->s_nr_users));
2625                 goto out_journal;
2626         }
2627         EXT4_SB(sb)->journal_bdev = bdev;
2628         ext4_init_journal_params(sb, journal);
2629         return journal;
2630 out_journal:
2631         jbd2_journal_destroy(journal);
2632 out_bdev:
2633         ext4_blkdev_put(bdev);
2634         return NULL;
2635 }
2636
2637 static int ext4_load_journal(struct super_block *sb,
2638                              struct ext4_super_block *es,
2639                              unsigned long journal_devnum)
2640 {
2641         journal_t *journal;
2642         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2643         dev_t journal_dev;
2644         int err = 0;
2645         int really_read_only;
2646
2647         if (journal_devnum &&
2648             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2649                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2650                         "numbers have changed\n");
2651                 journal_dev = new_decode_dev(journal_devnum);
2652         } else
2653                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2654
2655         really_read_only = bdev_read_only(sb->s_bdev);
2656
2657         /*
2658          * Are we loading a blank journal or performing recovery after a
2659          * crash?  For recovery, we need to check in advance whether we
2660          * can get read-write access to the device.
2661          */
2662
2663         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2664                 if (sb->s_flags & MS_RDONLY) {
2665                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2666                                         "required on readonly filesystem.\n");
2667                         if (really_read_only) {
2668                                 printk(KERN_ERR "EXT4-fs: write access "
2669                                         "unavailable, cannot proceed.\n");
2670                                 return -EROFS;
2671                         }
2672                         printk (KERN_INFO "EXT4-fs: write access will "
2673                                         "be enabled during recovery.\n");
2674                 }
2675         }
2676
2677         if (journal_inum && journal_dev) {
2678                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2679                        "and inode journals!\n");
2680                 return -EINVAL;
2681         }
2682
2683         if (journal_inum) {
2684                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2685                         return -EINVAL;
2686         } else {
2687                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2688                         return -EINVAL;
2689         }
2690
2691         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2692                 err = jbd2_journal_update_format(journal);
2693                 if (err)  {
2694                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2695                         jbd2_journal_destroy(journal);
2696                         return err;
2697                 }
2698         }
2699
2700         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2701                 err = jbd2_journal_wipe(journal, !really_read_only);
2702         if (!err)
2703                 err = jbd2_journal_load(journal);
2704
2705         if (err) {
2706                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2707                 jbd2_journal_destroy(journal);
2708                 return err;
2709         }
2710
2711         EXT4_SB(sb)->s_journal = journal;
2712         ext4_clear_journal_err(sb, es);
2713
2714         if (journal_devnum &&
2715             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2716                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2717                 sb->s_dirt = 1;
2718
2719                 /* Make sure we flush the recovery flag to disk. */
2720                 ext4_commit_super(sb, es, 1);
2721         }
2722
2723         return 0;
2724 }
2725
2726 static int ext4_create_journal(struct super_block * sb,
2727                                struct ext4_super_block * es,
2728                                unsigned int journal_inum)
2729 {
2730         journal_t *journal;
2731         int err;
2732
2733         if (sb->s_flags & MS_RDONLY) {
2734                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2735                                 "create journal.\n");
2736                 return -EROFS;
2737         }
2738
2739         journal = ext4_get_journal(sb, journal_inum);
2740         if (!journal)
2741                 return -EINVAL;
2742
2743         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2744                journal_inum);
2745
2746         err = jbd2_journal_create(journal);
2747         if (err) {
2748                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2749                 jbd2_journal_destroy(journal);
2750                 return -EIO;
2751         }
2752
2753         EXT4_SB(sb)->s_journal = journal;
2754
2755         ext4_update_dynamic_rev(sb);
2756         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2757         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2758
2759         es->s_journal_inum = cpu_to_le32(journal_inum);
2760         sb->s_dirt = 1;
2761
2762         /* Make sure we flush the recovery flag to disk. */
2763         ext4_commit_super(sb, es, 1);
2764
2765         return 0;
2766 }
2767
2768 static void ext4_commit_super (struct super_block * sb,
2769                                struct ext4_super_block * es,
2770                                int sync)
2771 {
2772         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2773
2774         if (!sbh)
2775                 return;
2776         es->s_wtime = cpu_to_le32(get_seconds());
2777         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2778         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2779         BUFFER_TRACE(sbh, "marking dirty");
2780         mark_buffer_dirty(sbh);
2781         if (sync)
2782                 sync_dirty_buffer(sbh);
2783 }
2784
2785
2786 /*
2787  * Have we just finished recovery?  If so, and if we are mounting (or
2788  * remounting) the filesystem readonly, then we will end up with a
2789  * consistent fs on disk.  Record that fact.
2790  */
2791 static void ext4_mark_recovery_complete(struct super_block * sb,
2792                                         struct ext4_super_block * es)
2793 {
2794         journal_t *journal = EXT4_SB(sb)->s_journal;
2795
2796         jbd2_journal_lock_updates(journal);
2797         jbd2_journal_flush(journal);
2798         lock_super(sb);
2799         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2800             sb->s_flags & MS_RDONLY) {
2801                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2802                 sb->s_dirt = 0;
2803                 ext4_commit_super(sb, es, 1);
2804         }
2805         unlock_super(sb);
2806         jbd2_journal_unlock_updates(journal);
2807 }
2808
2809 /*
2810  * If we are mounting (or read-write remounting) a filesystem whose journal
2811  * has recorded an error from a previous lifetime, move that error to the
2812  * main filesystem now.
2813  */
2814 static void ext4_clear_journal_err(struct super_block * sb,
2815                                    struct ext4_super_block * es)
2816 {
2817         journal_t *journal;
2818         int j_errno;
2819         const char *errstr;
2820
2821         journal = EXT4_SB(sb)->s_journal;
2822
2823         /*
2824          * Now check for any error status which may have been recorded in the
2825          * journal by a prior ext4_error() or ext4_abort()
2826          */
2827
2828         j_errno = jbd2_journal_errno(journal);
2829         if (j_errno) {
2830                 char nbuf[16];
2831
2832                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2833                 ext4_warning(sb, __func__, "Filesystem error recorded "
2834                              "from previous mount: %s", errstr);
2835                 ext4_warning(sb, __func__, "Marking fs in need of "
2836                              "filesystem check.");
2837
2838                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2839                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2840                 ext4_commit_super (sb, es, 1);
2841
2842                 jbd2_journal_clear_err(journal);
2843         }
2844 }
2845
2846 /*
2847  * Force the running and committing transactions to commit,
2848  * and wait on the commit.
2849  */
2850 int ext4_force_commit(struct super_block *sb)
2851 {
2852         journal_t *journal;
2853         int ret;
2854
2855         if (sb->s_flags & MS_RDONLY)
2856                 return 0;
2857
2858         journal = EXT4_SB(sb)->s_journal;
2859         sb->s_dirt = 0;
2860         ret = ext4_journal_force_commit(journal);
2861         return ret;
2862 }
2863
2864 /*
2865  * Ext4 always journals updates to the superblock itself, so we don't
2866  * have to propagate any other updates to the superblock on disk at this
2867  * point.  Just start an async writeback to get the buffers on their way
2868  * to the disk.
2869  *
2870  * This implicitly triggers the writebehind on sync().
2871  */
2872
2873 static void ext4_write_super (struct super_block * sb)
2874 {
2875         if (mutex_trylock(&sb->s_lock) != 0)
2876                 BUG();
2877         sb->s_dirt = 0;
2878 }
2879
2880 static int ext4_sync_fs(struct super_block *sb, int wait)
2881 {
2882         tid_t target;
2883
2884         sb->s_dirt = 0;
2885         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2886                 if (wait)
2887                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2888         }
2889         return 0;
2890 }
2891
2892 /*
2893  * LVM calls this function before a (read-only) snapshot is created.  This
2894  * gives us a chance to flush the journal completely and mark the fs clean.
2895  */
2896 static void ext4_write_super_lockfs(struct super_block *sb)
2897 {
2898         sb->s_dirt = 0;
2899
2900         if (!(sb->s_flags & MS_RDONLY)) {
2901                 journal_t *journal = EXT4_SB(sb)->s_journal;
2902
2903                 /* Now we set up the journal barrier. */
2904                 jbd2_journal_lock_updates(journal);
2905                 jbd2_journal_flush(journal);
2906
2907                 /* Journal blocked and flushed, clear needs_recovery flag. */
2908                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2909                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2910         }
2911 }
2912
2913 /*
2914  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2915  * flag here, even though the filesystem is not technically dirty yet.
2916  */
2917 static void ext4_unlockfs(struct super_block *sb)
2918 {
2919         if (!(sb->s_flags & MS_RDONLY)) {
2920                 lock_super(sb);
2921                 /* Reser the needs_recovery flag before the fs is unlocked. */
2922                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2923                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2924                 unlock_super(sb);
2925                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2926         }
2927 }
2928
2929 static int ext4_remount (struct super_block * sb, int * flags, char * data)
2930 {
2931         struct ext4_super_block * es;
2932         struct ext4_sb_info *sbi = EXT4_SB(sb);
2933         ext4_fsblk_t n_blocks_count = 0;
2934         unsigned long old_sb_flags;
2935         struct ext4_mount_options old_opts;
2936         int err;
2937 #ifdef CONFIG_QUOTA
2938         int i;
2939 #endif
2940
2941         /* Store the original options */
2942         old_sb_flags = sb->s_flags;
2943         old_opts.s_mount_opt = sbi->s_mount_opt;
2944         old_opts.s_resuid = sbi->s_resuid;
2945         old_opts.s_resgid = sbi->s_resgid;
2946         old_opts.s_commit_interval = sbi->s_commit_interval;
2947 #ifdef CONFIG_QUOTA
2948         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
2949         for (i = 0; i < MAXQUOTAS; i++)
2950                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
2951 #endif
2952
2953         /*
2954          * Allow the "check" option to be passed as a remount option.
2955          */
2956         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
2957                 err = -EINVAL;
2958                 goto restore_opts;
2959         }
2960
2961         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
2962                 ext4_abort(sb, __func__, "Abort forced by user");
2963
2964         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2965                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2966
2967         es = sbi->s_es;
2968
2969         ext4_init_journal_params(sb, sbi->s_journal);
2970
2971         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
2972                 n_blocks_count > ext4_blocks_count(es)) {
2973                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
2974                         err = -EROFS;
2975                         goto restore_opts;
2976                 }
2977
2978                 if (*flags & MS_RDONLY) {
2979                         /*
2980                          * First of all, the unconditional stuff we have to do
2981                          * to disable replay of the journal when we next remount
2982                          */
2983                         sb->s_flags |= MS_RDONLY;
2984
2985                         /*
2986                          * OK, test if we are remounting a valid rw partition
2987                          * readonly, and if so set the rdonly flag and then
2988                          * mark the partition as valid again.
2989                          */
2990                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
2991                             (sbi->s_mount_state & EXT4_VALID_FS))
2992                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
2993
2994                         /*
2995                          * We have to unlock super so that we can wait for
2996                          * transactions.
2997                          */
2998                         unlock_super(sb);
2999                         ext4_mark_recovery_complete(sb, es);
3000                         lock_super(sb);
3001                 } else {
3002                         __le32 ret;
3003                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3004                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3005                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3006                                        "remount RDWR because of unsupported "
3007                                        "optional features (%x).\n",
3008                                        sb->s_id, le32_to_cpu(ret));
3009                                 err = -EROFS;
3010                                 goto restore_opts;
3011                         }
3012
3013                         /*
3014                          * If we have an unprocessed orphan list hanging
3015                          * around from a previously readonly bdev mount,
3016                          * require a full umount/remount for now.
3017                          */
3018                         if (es->s_last_orphan) {
3019                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3020                                        "remount RDWR because of unprocessed "
3021                                        "orphan inode list.  Please "
3022                                        "umount/remount instead.\n",
3023                                        sb->s_id);
3024                                 err = -EINVAL;
3025                                 goto restore_opts;
3026                         }
3027
3028                         /*
3029                          * Mounting a RDONLY partition read-write, so reread
3030                          * and store the current valid flag.  (It may have
3031                          * been changed by e2fsck since we originally mounted
3032                          * the partition.)
3033                          */
3034                         ext4_clear_journal_err(sb, es);
3035                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3036                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3037                                 goto restore_opts;
3038                         if (!ext4_setup_super (sb, es, 0))
3039                                 sb->s_flags &= ~MS_RDONLY;
3040                 }
3041         }
3042 #ifdef CONFIG_QUOTA
3043         /* Release old quota file names */
3044         for (i = 0; i < MAXQUOTAS; i++)
3045                 if (old_opts.s_qf_names[i] &&
3046                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3047                         kfree(old_opts.s_qf_names[i]);
3048 #endif
3049         return 0;
3050 restore_opts:
3051         sb->s_flags = old_sb_flags;
3052         sbi->s_mount_opt = old_opts.s_mount_opt;
3053         sbi->s_resuid = old_opts.s_resuid;
3054         sbi->s_resgid = old_opts.s_resgid;
3055         sbi->s_commit_interval = old_opts.s_commit_interval;
3056 #ifdef CONFIG_QUOTA
3057         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3058         for (i = 0; i < MAXQUOTAS; i++) {
3059                 if (sbi->s_qf_names[i] &&
3060                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3061                         kfree(sbi->s_qf_names[i]);
3062                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3063         }
3064 #endif
3065         return err;
3066 }
3067
3068 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
3069 {
3070         struct super_block *sb = dentry->d_sb;
3071         struct ext4_sb_info *sbi = EXT4_SB(sb);
3072         struct ext4_super_block *es = sbi->s_es;
3073         u64 fsid;
3074
3075         if (test_opt(sb, MINIX_DF)) {
3076                 sbi->s_overhead_last = 0;
3077         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3078                 ext4_group_t ngroups = sbi->s_groups_count, i;
3079                 ext4_fsblk_t overhead = 0;
3080                 smp_rmb();
3081
3082                 /*
3083                  * Compute the overhead (FS structures).  This is constant
3084                  * for a given filesystem unless the number of block groups
3085                  * changes so we cache the previous value until it does.
3086                  */
3087
3088                 /*
3089                  * All of the blocks before first_data_block are
3090                  * overhead
3091                  */
3092                 overhead = le32_to_cpu(es->s_first_data_block);
3093
3094                 /*
3095                  * Add the overhead attributed to the superblock and
3096                  * block group descriptors.  If the sparse superblocks
3097                  * feature is turned on, then not all groups have this.
3098                  */
3099                 for (i = 0; i < ngroups; i++) {
3100                         overhead += ext4_bg_has_super(sb, i) +
3101                                 ext4_bg_num_gdb(sb, i);
3102                         cond_resched();
3103                 }
3104
3105                 /*
3106                  * Every block group has an inode bitmap, a block
3107                  * bitmap, and an inode table.
3108                  */
3109                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3110                 sbi->s_overhead_last = overhead;
3111                 smp_wmb();
3112                 sbi->s_blocks_last = ext4_blocks_count(es);
3113         }
3114
3115         buf->f_type = EXT4_SUPER_MAGIC;
3116         buf->f_bsize = sb->s_blocksize;
3117         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3118         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter);
3119         ext4_free_blocks_count_set(es, buf->f_bfree);
3120         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3121         if (buf->f_bfree < ext4_r_blocks_count(es))
3122                 buf->f_bavail = 0;
3123         buf->f_files = le32_to_cpu(es->s_inodes_count);
3124         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3125         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3126         buf->f_namelen = EXT4_NAME_LEN;
3127         fsid = le64_to_cpup((void *)es->s_uuid) ^
3128                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3129         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3130         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3131         return 0;
3132 }
3133
3134 /* Helper function for writing quotas on sync - we need to start transaction before quota file
3135  * is locked for write. Otherwise the are possible deadlocks:
3136  * Process 1                         Process 2
3137  * ext4_create()                     quota_sync()
3138  *   jbd2_journal_start()                   write_dquot()
3139  *   DQUOT_INIT()                        down(dqio_mutex)
3140  *     down(dqio_mutex)                    jbd2_journal_start()
3141  *
3142  */
3143
3144 #ifdef CONFIG_QUOTA
3145
3146 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3147 {
3148         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3149 }
3150
3151 static int ext4_dquot_initialize(struct inode *inode, int type)
3152 {
3153         handle_t *handle;
3154         int ret, err;
3155
3156         /* We may create quota structure so we need to reserve enough blocks */
3157         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
3158         if (IS_ERR(handle))
3159                 return PTR_ERR(handle);
3160         ret = dquot_initialize(inode, type);
3161         err = ext4_journal_stop(handle);
3162         if (!ret)
3163                 ret = err;
3164         return ret;
3165 }
3166
3167 static int ext4_dquot_drop(struct inode *inode)
3168 {
3169         handle_t *handle;
3170         int ret, err;
3171
3172         /* We may delete quota structure so we need to reserve enough blocks */
3173         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
3174         if (IS_ERR(handle)) {
3175                 /*
3176                  * We call dquot_drop() anyway to at least release references
3177                  * to quota structures so that umount does not hang.
3178                  */
3179                 dquot_drop(inode);
3180                 return PTR_ERR(handle);
3181         }
3182         ret = dquot_drop(inode);
3183         err = ext4_journal_stop(handle);
3184         if (!ret)
3185                 ret = err;
3186         return ret;
3187 }
3188
3189 static int ext4_write_dquot(struct dquot *dquot)
3190 {
3191         int ret, err;
3192         handle_t *handle;
3193         struct inode *inode;
3194
3195         inode = dquot_to_inode(dquot);
3196         handle = ext4_journal_start(inode,
3197                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3198         if (IS_ERR(handle))
3199                 return PTR_ERR(handle);
3200         ret = dquot_commit(dquot);
3201         err = ext4_journal_stop(handle);
3202         if (!ret)
3203                 ret = err;
3204         return ret;
3205 }
3206
3207 static int ext4_acquire_dquot(struct dquot *dquot)
3208 {
3209         int ret, err;
3210         handle_t *handle;
3211
3212         handle = ext4_journal_start(dquot_to_inode(dquot),
3213                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3214         if (IS_ERR(handle))
3215                 return PTR_ERR(handle);
3216         ret = dquot_acquire(dquot);
3217         err = ext4_journal_stop(handle);
3218         if (!ret)
3219                 ret = err;
3220         return ret;
3221 }
3222
3223 static int ext4_release_dquot(struct dquot *dquot)
3224 {
3225         int ret, err;
3226         handle_t *handle;
3227
3228         handle = ext4_journal_start(dquot_to_inode(dquot),
3229                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3230         if (IS_ERR(handle)) {
3231                 /* Release dquot anyway to avoid endless cycle in dqput() */
3232                 dquot_release(dquot);
3233                 return PTR_ERR(handle);
3234         }
3235         ret = dquot_release(dquot);
3236         err = ext4_journal_stop(handle);
3237         if (!ret)
3238                 ret = err;
3239         return ret;
3240 }
3241
3242 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3243 {
3244         /* Are we journaling quotas? */
3245         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3246             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3247                 dquot_mark_dquot_dirty(dquot);
3248                 return ext4_write_dquot(dquot);
3249         } else {
3250                 return dquot_mark_dquot_dirty(dquot);
3251         }
3252 }
3253
3254 static int ext4_write_info(struct super_block *sb, int type)
3255 {
3256         int ret, err;
3257         handle_t *handle;
3258
3259         /* Data block + inode block */
3260         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3261         if (IS_ERR(handle))
3262                 return PTR_ERR(handle);
3263         ret = dquot_commit_info(sb, type);
3264         err = ext4_journal_stop(handle);
3265         if (!ret)
3266                 ret = err;
3267         return ret;
3268 }
3269
3270 /*
3271  * Turn on quotas during mount time - we need to find
3272  * the quota file and such...
3273  */
3274 static int ext4_quota_on_mount(struct super_block *sb, int type)
3275 {
3276         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3277                         EXT4_SB(sb)->s_jquota_fmt, type);
3278 }
3279
3280 /*
3281  * Standard function to be called on quota_on
3282  */
3283 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3284                          char *path, int remount)
3285 {
3286         int err;
3287         struct nameidata nd;
3288
3289         if (!test_opt(sb, QUOTA))
3290                 return -EINVAL;
3291         /* When remounting, no checks are needed and in fact, path is NULL */
3292         if (remount)
3293                 return vfs_quota_on(sb, type, format_id, path, remount);
3294
3295         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
3296         if (err)
3297                 return err;
3298
3299         /* Quotafile not on the same filesystem? */
3300         if (nd.path.mnt->mnt_sb != sb) {
3301                 path_put(&nd.path);
3302                 return -EXDEV;
3303         }
3304         /* Journaling quota? */
3305         if (EXT4_SB(sb)->s_qf_names[type]) {
3306                 /* Quotafile not of fs root? */
3307                 if (nd.path.dentry->d_parent->d_inode != sb->s_root->d_inode)
3308                         printk(KERN_WARNING
3309                                 "EXT4-fs: Quota file not on filesystem root. "
3310                                 "Journaled quota will not work.\n");
3311         }
3312
3313         /*
3314          * When we journal data on quota file, we have to flush journal to see
3315          * all updates to the file when we bypass pagecache...
3316          */
3317         if (ext4_should_journal_data(nd.path.dentry->d_inode)) {
3318                 /*
3319                  * We don't need to lock updates but journal_flush() could
3320                  * otherwise be livelocked...
3321                  */
3322                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3323                 jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3324                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3325         }
3326
3327         path_put(&nd.path);
3328         return vfs_quota_on(sb, type, format_id, path, remount);
3329 }
3330
3331 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3332  * acquiring the locks... As quota files are never truncated and quota code
3333  * itself serializes the operations (and noone else should touch the files)
3334  * we don't have to be afraid of races */
3335 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3336                                size_t len, loff_t off)
3337 {
3338         struct inode *inode = sb_dqopt(sb)->files[type];
3339         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3340         int err = 0;
3341         int offset = off & (sb->s_blocksize - 1);
3342         int tocopy;
3343         size_t toread;
3344         struct buffer_head *bh;
3345         loff_t i_size = i_size_read(inode);
3346
3347         if (off > i_size)
3348                 return 0;
3349         if (off+len > i_size)
3350                 len = i_size-off;
3351         toread = len;
3352         while (toread > 0) {
3353                 tocopy = sb->s_blocksize - offset < toread ?
3354                                 sb->s_blocksize - offset : toread;
3355                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3356                 if (err)
3357                         return err;
3358                 if (!bh)        /* A hole? */
3359                         memset(data, 0, tocopy);
3360                 else
3361                         memcpy(data, bh->b_data+offset, tocopy);
3362                 brelse(bh);
3363                 offset = 0;
3364                 toread -= tocopy;
3365                 data += tocopy;
3366                 blk++;
3367         }
3368         return len;
3369 }
3370
3371 /* Write to quotafile (we know the transaction is already started and has
3372  * enough credits) */
3373 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3374                                 const char *data, size_t len, loff_t off)
3375 {
3376         struct inode *inode = sb_dqopt(sb)->files[type];
3377         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3378         int err = 0;
3379         int offset = off & (sb->s_blocksize - 1);
3380         int tocopy;
3381         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3382         size_t towrite = len;
3383         struct buffer_head *bh;
3384         handle_t *handle = journal_current_handle();
3385
3386         if (!handle) {
3387                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%Lu, len=%Lu)"
3388                         " cancelled because transaction is not started.\n",
3389                         (unsigned long long)off, (unsigned long long)len);
3390                 return -EIO;
3391         }
3392         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3393         while (towrite > 0) {
3394                 tocopy = sb->s_blocksize - offset < towrite ?
3395                                 sb->s_blocksize - offset : towrite;
3396                 bh = ext4_bread(handle, inode, blk, 1, &err);
3397                 if (!bh)
3398                         goto out;
3399                 if (journal_quota) {
3400                         err = ext4_journal_get_write_access(handle, bh);
3401                         if (err) {
3402                                 brelse(bh);
3403                                 goto out;
3404                         }
3405                 }
3406                 lock_buffer(bh);
3407                 memcpy(bh->b_data+offset, data, tocopy);
3408                 flush_dcache_page(bh->b_page);
3409                 unlock_buffer(bh);
3410                 if (journal_quota)
3411                         err = ext4_journal_dirty_metadata(handle, bh);
3412                 else {
3413                         /* Always do at least ordered writes for quotas */
3414                         err = ext4_jbd2_file_inode(handle, inode);
3415                         mark_buffer_dirty(bh);
3416                 }
3417                 brelse(bh);
3418                 if (err)
3419                         goto out;
3420                 offset = 0;
3421                 towrite -= tocopy;
3422                 data += tocopy;
3423                 blk++;
3424         }
3425 out:
3426         if (len == towrite) {
3427                 mutex_unlock(&inode->i_mutex);
3428                 return err;
3429         }
3430         if (inode->i_size < off+len-towrite) {
3431                 i_size_write(inode, off+len-towrite);
3432                 EXT4_I(inode)->i_disksize = inode->i_size;
3433         }
3434         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3435         ext4_mark_inode_dirty(handle, inode);
3436         mutex_unlock(&inode->i_mutex);
3437         return len - towrite;
3438 }
3439
3440 #endif
3441
3442 static int ext4_get_sb(struct file_system_type *fs_type,
3443         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3444 {
3445         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3446 }
3447
3448 static struct file_system_type ext4dev_fs_type = {
3449         .owner          = THIS_MODULE,
3450         .name           = "ext4dev",
3451         .get_sb         = ext4_get_sb,
3452         .kill_sb        = kill_block_super,
3453         .fs_flags       = FS_REQUIRES_DEV,
3454 };
3455
3456 static int __init init_ext4_fs(void)
3457 {
3458         int err;
3459
3460         err = init_ext4_mballoc();
3461         if (err)
3462                 return err;
3463
3464         err = init_ext4_xattr();
3465         if (err)
3466                 goto out2;
3467         err = init_inodecache();
3468         if (err)
3469                 goto out1;
3470         err = register_filesystem(&ext4dev_fs_type);
3471         if (err)
3472                 goto out;
3473         return 0;
3474 out:
3475         destroy_inodecache();
3476 out1:
3477         exit_ext4_xattr();
3478 out2:
3479         exit_ext4_mballoc();
3480         return err;
3481 }
3482
3483 static void __exit exit_ext4_fs(void)
3484 {
3485         unregister_filesystem(&ext4dev_fs_type);
3486         destroy_inodecache();
3487         exit_ext4_xattr();
3488         exit_ext4_mballoc();
3489 }
3490
3491 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
3492 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
3493 MODULE_LICENSE("GPL");
3494 module_init(init_ext4_fs)
3495 module_exit(exit_ext4_fs)