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(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         ext4_fsblk_t last_block;
1008
1009         if (!options)
1010                 return 1;
1011
1012         while ((p = strsep (&options, ",")) != NULL) {
1013                 int token;
1014                 if (!*p)
1015                         continue;
1016
1017                 token = match_token(p, tokens, args);
1018                 switch (token) {
1019                 case Opt_bsd_df:
1020                         clear_opt (sbi->s_mount_opt, MINIX_DF);
1021                         break;
1022                 case Opt_minix_df:
1023                         set_opt (sbi->s_mount_opt, MINIX_DF);
1024                         break;
1025                 case Opt_grpid:
1026                         set_opt (sbi->s_mount_opt, GRPID);
1027                         break;
1028                 case Opt_nogrpid:
1029                         clear_opt (sbi->s_mount_opt, GRPID);
1030                         break;
1031                 case Opt_resuid:
1032                         if (match_int(&args[0], &option))
1033                                 return 0;
1034                         sbi->s_resuid = option;
1035                         break;
1036                 case Opt_resgid:
1037                         if (match_int(&args[0], &option))
1038                                 return 0;
1039                         sbi->s_resgid = option;
1040                         break;
1041                 case Opt_sb:
1042                         /* handled by get_sb_block() instead of here */
1043                         /* *sb_block = match_int(&args[0]); */
1044                         break;
1045                 case Opt_err_panic:
1046                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
1047                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
1048                         set_opt (sbi->s_mount_opt, ERRORS_PANIC);
1049                         break;
1050                 case Opt_err_ro:
1051                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
1052                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
1053                         set_opt (sbi->s_mount_opt, ERRORS_RO);
1054                         break;
1055                 case Opt_err_cont:
1056                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
1057                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
1058                         set_opt (sbi->s_mount_opt, ERRORS_CONT);
1059                         break;
1060                 case Opt_nouid32:
1061                         set_opt (sbi->s_mount_opt, NO_UID32);
1062                         break;
1063                 case Opt_nocheck:
1064                         clear_opt (sbi->s_mount_opt, CHECK);
1065                         break;
1066                 case Opt_debug:
1067                         set_opt (sbi->s_mount_opt, DEBUG);
1068                         break;
1069                 case Opt_oldalloc:
1070                         set_opt (sbi->s_mount_opt, OLDALLOC);
1071                         break;
1072                 case Opt_orlov:
1073                         clear_opt (sbi->s_mount_opt, OLDALLOC);
1074                         break;
1075 #ifdef CONFIG_EXT4DEV_FS_XATTR
1076                 case Opt_user_xattr:
1077                         set_opt (sbi->s_mount_opt, XATTR_USER);
1078                         break;
1079                 case Opt_nouser_xattr:
1080                         clear_opt (sbi->s_mount_opt, XATTR_USER);
1081                         break;
1082 #else
1083                 case Opt_user_xattr:
1084                 case Opt_nouser_xattr:
1085                         printk("EXT4 (no)user_xattr options not supported\n");
1086                         break;
1087 #endif
1088 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1089                 case Opt_acl:
1090                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1091                         break;
1092                 case Opt_noacl:
1093                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1094                         break;
1095 #else
1096                 case Opt_acl:
1097                 case Opt_noacl:
1098                         printk("EXT4 (no)acl options not supported\n");
1099                         break;
1100 #endif
1101                 case Opt_reservation:
1102                         set_opt(sbi->s_mount_opt, RESERVATION);
1103                         break;
1104                 case Opt_noreservation:
1105                         clear_opt(sbi->s_mount_opt, RESERVATION);
1106                         break;
1107                 case Opt_journal_update:
1108                         /* @@@ FIXME */
1109                         /* Eventually we will want to be able to create
1110                            a journal file here.  For now, only allow the
1111                            user to specify an existing inode to be the
1112                            journal file. */
1113                         if (is_remount) {
1114                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1115                                        "journal on remount\n");
1116                                 return 0;
1117                         }
1118                         set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
1119                         break;
1120                 case Opt_journal_inum:
1121                         if (is_remount) {
1122                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1123                                        "journal on remount\n");
1124                                 return 0;
1125                         }
1126                         if (match_int(&args[0], &option))
1127                                 return 0;
1128                         *inum = option;
1129                         break;
1130                 case Opt_journal_dev:
1131                         if (is_remount) {
1132                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1133                                        "journal on remount\n");
1134                                 return 0;
1135                         }
1136                         if (match_int(&args[0], &option))
1137                                 return 0;
1138                         *journal_devnum = option;
1139                         break;
1140                 case Opt_journal_checksum:
1141                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1142                         break;
1143                 case Opt_journal_async_commit:
1144                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1145                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1146                         break;
1147                 case Opt_noload:
1148                         set_opt (sbi->s_mount_opt, NOLOAD);
1149                         break;
1150                 case Opt_commit:
1151                         if (match_int(&args[0], &option))
1152                                 return 0;
1153                         if (option < 0)
1154                                 return 0;
1155                         if (option == 0)
1156                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1157                         sbi->s_commit_interval = HZ * option;
1158                         break;
1159                 case Opt_data_journal:
1160                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1161                         goto datacheck;
1162                 case Opt_data_ordered:
1163                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1164                         goto datacheck;
1165                 case Opt_data_writeback:
1166                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1167                 datacheck:
1168                         if (is_remount) {
1169                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1170                                                 != data_opt) {
1171                                         printk(KERN_ERR
1172                                                 "EXT4-fs: cannot change data "
1173                                                 "mode on remount\n");
1174                                         return 0;
1175                                 }
1176                         } else {
1177                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1178                                 sbi->s_mount_opt |= data_opt;
1179                         }
1180                         break;
1181 #ifdef CONFIG_QUOTA
1182                 case Opt_usrjquota:
1183                         qtype = USRQUOTA;
1184                         goto set_qf_name;
1185                 case Opt_grpjquota:
1186                         qtype = GRPQUOTA;
1187 set_qf_name:
1188                         if ((sb_any_quota_enabled(sb) ||
1189                              sb_any_quota_suspended(sb)) &&
1190                             !sbi->s_qf_names[qtype]) {
1191                                 printk(KERN_ERR
1192                                         "EXT4-fs: Cannot change journaled "
1193                                         "quota options when quota turned on.\n");
1194                                 return 0;
1195                         }
1196                         qname = match_strdup(&args[0]);
1197                         if (!qname) {
1198                                 printk(KERN_ERR
1199                                         "EXT4-fs: not enough memory for "
1200                                         "storing quotafile name.\n");
1201                                 return 0;
1202                         }
1203                         if (sbi->s_qf_names[qtype] &&
1204                             strcmp(sbi->s_qf_names[qtype], qname)) {
1205                                 printk(KERN_ERR
1206                                         "EXT4-fs: %s quota file already "
1207                                         "specified.\n", QTYPE2NAME(qtype));
1208                                 kfree(qname);
1209                                 return 0;
1210                         }
1211                         sbi->s_qf_names[qtype] = qname;
1212                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1213                                 printk(KERN_ERR
1214                                         "EXT4-fs: quotafile must be on "
1215                                         "filesystem root.\n");
1216                                 kfree(sbi->s_qf_names[qtype]);
1217                                 sbi->s_qf_names[qtype] = NULL;
1218                                 return 0;
1219                         }
1220                         set_opt(sbi->s_mount_opt, QUOTA);
1221                         break;
1222                 case Opt_offusrjquota:
1223                         qtype = USRQUOTA;
1224                         goto clear_qf_name;
1225                 case Opt_offgrpjquota:
1226                         qtype = GRPQUOTA;
1227 clear_qf_name:
1228                         if ((sb_any_quota_enabled(sb) ||
1229                              sb_any_quota_suspended(sb)) &&
1230                             sbi->s_qf_names[qtype]) {
1231                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1232                                         "journaled quota options when "
1233                                         "quota turned on.\n");
1234                                 return 0;
1235                         }
1236                         /*
1237                          * The space will be released later when all options
1238                          * are confirmed to be correct
1239                          */
1240                         sbi->s_qf_names[qtype] = NULL;
1241                         break;
1242                 case Opt_jqfmt_vfsold:
1243                         qfmt = QFMT_VFS_OLD;
1244                         goto set_qf_format;
1245                 case Opt_jqfmt_vfsv0:
1246                         qfmt = QFMT_VFS_V0;
1247 set_qf_format:
1248                         if ((sb_any_quota_enabled(sb) ||
1249                              sb_any_quota_suspended(sb)) &&
1250                             sbi->s_jquota_fmt != qfmt) {
1251                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1252                                         "journaled quota options when "
1253                                         "quota turned on.\n");
1254                                 return 0;
1255                         }
1256                         sbi->s_jquota_fmt = qfmt;
1257                         break;
1258                 case Opt_quota:
1259                 case Opt_usrquota:
1260                         set_opt(sbi->s_mount_opt, QUOTA);
1261                         set_opt(sbi->s_mount_opt, USRQUOTA);
1262                         break;
1263                 case Opt_grpquota:
1264                         set_opt(sbi->s_mount_opt, QUOTA);
1265                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1266                         break;
1267                 case Opt_noquota:
1268                         if (sb_any_quota_enabled(sb)) {
1269                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1270                                         "options when quota turned on.\n");
1271                                 return 0;
1272                         }
1273                         clear_opt(sbi->s_mount_opt, QUOTA);
1274                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1275                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1276                         break;
1277 #else
1278                 case Opt_quota:
1279                 case Opt_usrquota:
1280                 case Opt_grpquota:
1281                         printk(KERN_ERR
1282                                 "EXT4-fs: quota options not supported.\n");
1283                         break;
1284                 case Opt_usrjquota:
1285                 case Opt_grpjquota:
1286                 case Opt_offusrjquota:
1287                 case Opt_offgrpjquota:
1288                 case Opt_jqfmt_vfsold:
1289                 case Opt_jqfmt_vfsv0:
1290                         printk(KERN_ERR
1291                                 "EXT4-fs: journaled quota options not "
1292                                 "supported.\n");
1293                         break;
1294                 case Opt_noquota:
1295                         break;
1296 #endif
1297                 case Opt_abort:
1298                         set_opt(sbi->s_mount_opt, ABORT);
1299                         break;
1300                 case Opt_barrier:
1301                         if (match_int(&args[0], &option))
1302                                 return 0;
1303                         if (option)
1304                                 set_opt(sbi->s_mount_opt, BARRIER);
1305                         else
1306                                 clear_opt(sbi->s_mount_opt, BARRIER);
1307                         break;
1308                 case Opt_ignore:
1309                         break;
1310                 case Opt_resize:
1311                         if (!is_remount) {
1312                                 printk("EXT4-fs: resize option only available "
1313                                         "for remount\n");
1314                                 return 0;
1315                         }
1316                         if (match_int(&args[0], &option) != 0)
1317                                 return 0;
1318                         *n_blocks_count = option;
1319                         break;
1320                 case Opt_nobh:
1321                         set_opt(sbi->s_mount_opt, NOBH);
1322                         break;
1323                 case Opt_bh:
1324                         clear_opt(sbi->s_mount_opt, NOBH);
1325                         break;
1326                 case Opt_extents:
1327                         if (!EXT4_HAS_INCOMPAT_FEATURE(sb,
1328                                         EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1329                                 ext4_warning(sb, __func__,
1330                                         "extents feature not enabled "
1331                                         "on this filesystem, use tune2fs\n");
1332                                 return 0;
1333                         }
1334                         set_opt (sbi->s_mount_opt, EXTENTS);
1335                         break;
1336                 case Opt_noextents:
1337                         /*
1338                          * When e2fsprogs support resizing an already existing
1339                          * ext3 file system to greater than 2**32 we need to
1340                          * add support to block allocator to handle growing
1341                          * already existing block  mapped inode so that blocks
1342                          * allocated for them fall within 2**32
1343                          */
1344                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1345                         if (last_block  > 0xffffffffULL) {
1346                                 printk(KERN_ERR "EXT4-fs: Filesystem too "
1347                                                 "large to mount with "
1348                                                 "-o noextents options\n");
1349                                 return 0;
1350                         }
1351                         clear_opt (sbi->s_mount_opt, EXTENTS);
1352                         break;
1353                 case Opt_i_version:
1354                         set_opt(sbi->s_mount_opt, I_VERSION);
1355                         sb->s_flags |= MS_I_VERSION;
1356                         break;
1357                 case Opt_nodelalloc:
1358                         clear_opt(sbi->s_mount_opt, DELALLOC);
1359                         break;
1360                 case Opt_mballoc:
1361                         set_opt(sbi->s_mount_opt, MBALLOC);
1362                         break;
1363                 case Opt_nomballoc:
1364                         clear_opt(sbi->s_mount_opt, MBALLOC);
1365                         break;
1366                 case Opt_stripe:
1367                         if (match_int(&args[0], &option))
1368                                 return 0;
1369                         if (option < 0)
1370                                 return 0;
1371                         sbi->s_stripe = option;
1372                         break;
1373                 case Opt_delalloc:
1374                         set_opt(sbi->s_mount_opt, DELALLOC);
1375                         break;
1376                 default:
1377                         printk (KERN_ERR
1378                                 "EXT4-fs: Unrecognized mount option \"%s\" "
1379                                 "or missing value\n", p);
1380                         return 0;
1381                 }
1382         }
1383 #ifdef CONFIG_QUOTA
1384         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1385                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1386                      sbi->s_qf_names[USRQUOTA])
1387                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1388
1389                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1390                      sbi->s_qf_names[GRPQUOTA])
1391                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1392
1393                 if ((sbi->s_qf_names[USRQUOTA] &&
1394                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1395                     (sbi->s_qf_names[GRPQUOTA] &&
1396                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1397                         printk(KERN_ERR "EXT4-fs: old and new quota "
1398                                         "format mixing.\n");
1399                         return 0;
1400                 }
1401
1402                 if (!sbi->s_jquota_fmt) {
1403                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1404                                         "not specified.\n");
1405                         return 0;
1406                 }
1407         } else {
1408                 if (sbi->s_jquota_fmt) {
1409                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1410                                         "specified with no journaling "
1411                                         "enabled.\n");
1412                         return 0;
1413                 }
1414         }
1415 #endif
1416         return 1;
1417 }
1418
1419 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1420                             int read_only)
1421 {
1422         struct ext4_sb_info *sbi = EXT4_SB(sb);
1423         int res = 0;
1424
1425         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1426                 printk (KERN_ERR "EXT4-fs warning: revision level too high, "
1427                         "forcing read-only mode\n");
1428                 res = MS_RDONLY;
1429         }
1430         if (read_only)
1431                 return res;
1432         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1433                 printk (KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1434                         "running e2fsck is recommended\n");
1435         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1436                 printk (KERN_WARNING
1437                         "EXT4-fs warning: mounting fs with errors, "
1438                         "running e2fsck is recommended\n");
1439         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1440                  le16_to_cpu(es->s_mnt_count) >=
1441                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1442                 printk (KERN_WARNING
1443                         "EXT4-fs warning: maximal mount count reached, "
1444                         "running e2fsck is recommended\n");
1445         else if (le32_to_cpu(es->s_checkinterval) &&
1446                 (le32_to_cpu(es->s_lastcheck) +
1447                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1448                 printk (KERN_WARNING
1449                         "EXT4-fs warning: checktime reached, "
1450                         "running e2fsck is recommended\n");
1451 #if 0
1452                 /* @@@ We _will_ want to clear the valid bit if we find
1453                  * inconsistencies, to force a fsck at reboot.  But for
1454                  * a plain journaled filesystem we can keep it set as
1455                  * valid forever! :)
1456                  */
1457         es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1458 #endif
1459         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1460                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1461         le16_add_cpu(&es->s_mnt_count, 1);
1462         es->s_mtime = cpu_to_le32(get_seconds());
1463         ext4_update_dynamic_rev(sb);
1464         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1465
1466         ext4_commit_super(sb, es, 1);
1467         if (test_opt(sb, DEBUG))
1468                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1469                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1470                         sb->s_blocksize,
1471                         sbi->s_groups_count,
1472                         EXT4_BLOCKS_PER_GROUP(sb),
1473                         EXT4_INODES_PER_GROUP(sb),
1474                         sbi->s_mount_opt);
1475
1476         printk(KERN_INFO "EXT4 FS on %s, ", sb->s_id);
1477         if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
1478                 char b[BDEVNAME_SIZE];
1479
1480                 printk("external journal on %s\n",
1481                         bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
1482         } else {
1483                 printk("internal journal\n");
1484         }
1485         return res;
1486 }
1487
1488 static int ext4_fill_flex_info(struct super_block *sb)
1489 {
1490         struct ext4_sb_info *sbi = EXT4_SB(sb);
1491         struct ext4_group_desc *gdp = NULL;
1492         struct buffer_head *bh;
1493         ext4_group_t flex_group_count;
1494         ext4_group_t flex_group;
1495         int groups_per_flex = 0;
1496         __u64 block_bitmap = 0;
1497         int i;
1498
1499         if (!sbi->s_es->s_log_groups_per_flex) {
1500                 sbi->s_log_groups_per_flex = 0;
1501                 return 1;
1502         }
1503
1504         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1505         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1506
1507         flex_group_count = (sbi->s_groups_count + groups_per_flex - 1) /
1508                 groups_per_flex;
1509         sbi->s_flex_groups = kmalloc(flex_group_count *
1510                                      sizeof(struct flex_groups), GFP_KERNEL);
1511         if (sbi->s_flex_groups == NULL) {
1512                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
1513                 goto failed;
1514         }
1515         memset(sbi->s_flex_groups, 0, flex_group_count *
1516                sizeof(struct flex_groups));
1517
1518         gdp = ext4_get_group_desc(sb, 1, &bh);
1519         block_bitmap = ext4_block_bitmap(sb, gdp) - 1;
1520
1521         for (i = 0; i < sbi->s_groups_count; i++) {
1522                 gdp = ext4_get_group_desc(sb, i, &bh);
1523
1524                 flex_group = ext4_flex_group(sbi, i);
1525                 sbi->s_flex_groups[flex_group].free_inodes +=
1526                         le16_to_cpu(gdp->bg_free_inodes_count);
1527                 sbi->s_flex_groups[flex_group].free_blocks +=
1528                         le16_to_cpu(gdp->bg_free_blocks_count);
1529         }
1530
1531         return 1;
1532 failed:
1533         return 0;
1534 }
1535
1536 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1537                             struct ext4_group_desc *gdp)
1538 {
1539         __u16 crc = 0;
1540
1541         if (sbi->s_es->s_feature_ro_compat &
1542             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1543                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1544                 __le32 le_group = cpu_to_le32(block_group);
1545
1546                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1547                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1548                 crc = crc16(crc, (__u8 *)gdp, offset);
1549                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1550                 /* for checksum of struct ext4_group_desc do the rest...*/
1551                 if ((sbi->s_es->s_feature_incompat &
1552                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1553                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1554                         crc = crc16(crc, (__u8 *)gdp + offset,
1555                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1556                                         offset);
1557         }
1558
1559         return cpu_to_le16(crc);
1560 }
1561
1562 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1563                                 struct ext4_group_desc *gdp)
1564 {
1565         if ((sbi->s_es->s_feature_ro_compat &
1566              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1567             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1568                 return 0;
1569
1570         return 1;
1571 }
1572
1573 /* Called at mount-time, super-block is locked */
1574 static int ext4_check_descriptors(struct super_block *sb)
1575 {
1576         struct ext4_sb_info *sbi = EXT4_SB(sb);
1577         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1578         ext4_fsblk_t last_block;
1579         ext4_fsblk_t block_bitmap;
1580         ext4_fsblk_t inode_bitmap;
1581         ext4_fsblk_t inode_table;
1582         int flexbg_flag = 0;
1583         ext4_group_t i;
1584
1585         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1586                 flexbg_flag = 1;
1587
1588         ext4_debug ("Checking group descriptors");
1589
1590         for (i = 0; i < sbi->s_groups_count; i++) {
1591                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1592
1593                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1594                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1595                 else
1596                         last_block = first_block +
1597                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1598
1599                 block_bitmap = ext4_block_bitmap(sb, gdp);
1600                 if (block_bitmap < first_block || block_bitmap > last_block)
1601                 {
1602                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1603                                "Block bitmap for group %lu not in group "
1604                                "(block %llu)!", i, block_bitmap);
1605                         return 0;
1606                 }
1607                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1608                 if (inode_bitmap < first_block || inode_bitmap > last_block)
1609                 {
1610                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1611                                "Inode bitmap for group %lu not in group "
1612                                "(block %llu)!", i, inode_bitmap);
1613                         return 0;
1614                 }
1615                 inode_table = ext4_inode_table(sb, gdp);
1616                 if (inode_table < first_block ||
1617                     inode_table + sbi->s_itb_per_group - 1 > last_block)
1618                 {
1619                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1620                                "Inode table for group %lu not in group "
1621                                "(block %llu)!", i, inode_table);
1622                         return 0;
1623                 }
1624                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1625                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1626                                "Checksum for group %lu failed (%u!=%u)\n",
1627                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1628                                gdp)), le16_to_cpu(gdp->bg_checksum));
1629                         if (!(sb->s_flags & MS_RDONLY))
1630                                 return 0;
1631                 }
1632                 if (!flexbg_flag)
1633                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1634         }
1635
1636         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1637         sbi->s_es->s_free_inodes_count=cpu_to_le32(ext4_count_free_inodes(sb));
1638         return 1;
1639 }
1640
1641 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1642  * the superblock) which were deleted from all directories, but held open by
1643  * a process at the time of a crash.  We walk the list and try to delete these
1644  * inodes at recovery time (only with a read-write filesystem).
1645  *
1646  * In order to keep the orphan inode chain consistent during traversal (in
1647  * case of crash during recovery), we link each inode into the superblock
1648  * orphan list_head and handle it the same way as an inode deletion during
1649  * normal operation (which journals the operations for us).
1650  *
1651  * We only do an iget() and an iput() on each inode, which is very safe if we
1652  * accidentally point at an in-use or already deleted inode.  The worst that
1653  * can happen in this case is that we get a "bit already cleared" message from
1654  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1655  * e2fsck was run on this filesystem, and it must have already done the orphan
1656  * inode cleanup for us, so we can safely abort without any further action.
1657  */
1658 static void ext4_orphan_cleanup (struct super_block * sb,
1659                                  struct ext4_super_block * es)
1660 {
1661         unsigned int s_flags = sb->s_flags;
1662         int nr_orphans = 0, nr_truncates = 0;
1663 #ifdef CONFIG_QUOTA
1664         int i;
1665 #endif
1666         if (!es->s_last_orphan) {
1667                 jbd_debug(4, "no orphan inodes to clean up\n");
1668                 return;
1669         }
1670
1671         if (bdev_read_only(sb->s_bdev)) {
1672                 printk(KERN_ERR "EXT4-fs: write access "
1673                         "unavailable, skipping orphan cleanup.\n");
1674                 return;
1675         }
1676
1677         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1678                 if (es->s_last_orphan)
1679                         jbd_debug(1, "Errors on filesystem, "
1680                                   "clearing orphan list.\n");
1681                 es->s_last_orphan = 0;
1682                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1683                 return;
1684         }
1685
1686         if (s_flags & MS_RDONLY) {
1687                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1688                        sb->s_id);
1689                 sb->s_flags &= ~MS_RDONLY;
1690         }
1691 #ifdef CONFIG_QUOTA
1692         /* Needed for iput() to work correctly and not trash data */
1693         sb->s_flags |= MS_ACTIVE;
1694         /* Turn on quotas so that they are updated correctly */
1695         for (i = 0; i < MAXQUOTAS; i++) {
1696                 if (EXT4_SB(sb)->s_qf_names[i]) {
1697                         int ret = ext4_quota_on_mount(sb, i);
1698                         if (ret < 0)
1699                                 printk(KERN_ERR
1700                                         "EXT4-fs: Cannot turn on journaled "
1701                                         "quota: error %d\n", ret);
1702                 }
1703         }
1704 #endif
1705
1706         while (es->s_last_orphan) {
1707                 struct inode *inode;
1708
1709                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1710                 if (IS_ERR(inode)) {
1711                         es->s_last_orphan = 0;
1712                         break;
1713                 }
1714
1715                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1716                 DQUOT_INIT(inode);
1717                 if (inode->i_nlink) {
1718                         printk(KERN_DEBUG
1719                                 "%s: truncating inode %lu to %Ld bytes\n",
1720                                 __func__, inode->i_ino, inode->i_size);
1721                         jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
1722                                   inode->i_ino, inode->i_size);
1723                         ext4_truncate(inode);
1724                         nr_truncates++;
1725                 } else {
1726                         printk(KERN_DEBUG
1727                                 "%s: deleting unreferenced inode %lu\n",
1728                                 __func__, inode->i_ino);
1729                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1730                                   inode->i_ino);
1731                         nr_orphans++;
1732                 }
1733                 iput(inode);  /* The delete magic happens here! */
1734         }
1735
1736 #define PLURAL(x) (x), ((x)==1) ? "" : "s"
1737
1738         if (nr_orphans)
1739                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1740                        sb->s_id, PLURAL(nr_orphans));
1741         if (nr_truncates)
1742                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1743                        sb->s_id, PLURAL(nr_truncates));
1744 #ifdef CONFIG_QUOTA
1745         /* Turn quotas off */
1746         for (i = 0; i < MAXQUOTAS; i++) {
1747                 if (sb_dqopt(sb)->files[i])
1748                         vfs_quota_off(sb, i, 0);
1749         }
1750 #endif
1751         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1752 }
1753 /*
1754  * Maximal extent format file size.
1755  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1756  * extent format containers, within a sector_t, and within i_blocks
1757  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1758  * so that won't be a limiting factor.
1759  *
1760  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1761  */
1762 static loff_t ext4_max_size(int blkbits)
1763 {
1764         loff_t res;
1765         loff_t upper_limit = MAX_LFS_FILESIZE;
1766
1767         /* small i_blocks in vfs inode? */
1768         if (sizeof(blkcnt_t) < sizeof(u64)) {
1769                 /*
1770                  * CONFIG_LSF is not enabled implies the inode
1771                  * i_block represent total blocks in 512 bytes
1772                  * 32 == size of vfs inode i_blocks * 8
1773                  */
1774                 upper_limit = (1LL << 32) - 1;
1775
1776                 /* total blocks in file system block size */
1777                 upper_limit >>= (blkbits - 9);
1778                 upper_limit <<= blkbits;
1779         }
1780
1781         /* 32-bit extent-start container, ee_block */
1782         res = 1LL << 32;
1783         res <<= blkbits;
1784         res -= 1;
1785
1786         /* Sanity check against vm- & vfs- imposed limits */
1787         if (res > upper_limit)
1788                 res = upper_limit;
1789
1790         return res;
1791 }
1792
1793 /*
1794  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1795  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1796  * We need to be 1 filesystem block less than the 2^48 sector limit.
1797  */
1798 static loff_t ext4_max_bitmap_size(int bits)
1799 {
1800         loff_t res = EXT4_NDIR_BLOCKS;
1801         int meta_blocks;
1802         loff_t upper_limit;
1803         /* This is calculated to be the largest file size for a
1804          * dense, bitmapped file such that the total number of
1805          * sectors in the file, including data and all indirect blocks,
1806          * does not exceed 2^48 -1
1807          * __u32 i_blocks_lo and _u16 i_blocks_high representing the
1808          * total number of  512 bytes blocks of the file
1809          */
1810
1811         if (sizeof(blkcnt_t) < sizeof(u64)) {
1812                 /*
1813                  * CONFIG_LSF is not enabled implies the inode
1814                  * i_block represent total blocks in 512 bytes
1815                  * 32 == size of vfs inode i_blocks * 8
1816                  */
1817                 upper_limit = (1LL << 32) - 1;
1818
1819                 /* total blocks in file system block size */
1820                 upper_limit >>= (bits - 9);
1821
1822         } else {
1823                 /*
1824                  * We use 48 bit ext4_inode i_blocks
1825                  * With EXT4_HUGE_FILE_FL set the i_blocks
1826                  * represent total number of blocks in
1827                  * file system block size
1828                  */
1829                 upper_limit = (1LL << 48) - 1;
1830
1831         }
1832
1833         /* indirect blocks */
1834         meta_blocks = 1;
1835         /* double indirect blocks */
1836         meta_blocks += 1 + (1LL << (bits-2));
1837         /* tripple indirect blocks */
1838         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
1839
1840         upper_limit -= meta_blocks;
1841         upper_limit <<= bits;
1842
1843         res += 1LL << (bits-2);
1844         res += 1LL << (2*(bits-2));
1845         res += 1LL << (3*(bits-2));
1846         res <<= bits;
1847         if (res > upper_limit)
1848                 res = upper_limit;
1849
1850         if (res > MAX_LFS_FILESIZE)
1851                 res = MAX_LFS_FILESIZE;
1852
1853         return res;
1854 }
1855
1856 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1857                                 ext4_fsblk_t logical_sb_block, int nr)
1858 {
1859         struct ext4_sb_info *sbi = EXT4_SB(sb);
1860         ext4_group_t bg, first_meta_bg;
1861         int has_super = 0;
1862
1863         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1864
1865         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1866             nr < first_meta_bg)
1867                 return logical_sb_block + nr + 1;
1868         bg = sbi->s_desc_per_block * nr;
1869         if (ext4_bg_has_super(sb, bg))
1870                 has_super = 1;
1871         return (has_super + ext4_group_first_block_no(sb, bg));
1872 }
1873
1874 /**
1875  * ext4_get_stripe_size: Get the stripe size.
1876  * @sbi: In memory super block info
1877  *
1878  * If we have specified it via mount option, then
1879  * use the mount option value. If the value specified at mount time is
1880  * greater than the blocks per group use the super block value.
1881  * If the super block value is greater than blocks per group return 0.
1882  * Allocator needs it be less than blocks per group.
1883  *
1884  */
1885 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
1886 {
1887         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
1888         unsigned long stripe_width =
1889                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
1890
1891         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
1892                 return sbi->s_stripe;
1893
1894         if (stripe_width <= sbi->s_blocks_per_group)
1895                 return stripe_width;
1896
1897         if (stride <= sbi->s_blocks_per_group)
1898                 return stride;
1899
1900         return 0;
1901 }
1902
1903 static int ext4_fill_super (struct super_block *sb, void *data, int silent)
1904                                 __releases(kernel_lock)
1905                                 __acquires(kernel_lock)
1906
1907 {
1908         struct buffer_head * bh;
1909         struct ext4_super_block *es = NULL;
1910         struct ext4_sb_info *sbi;
1911         ext4_fsblk_t block;
1912         ext4_fsblk_t sb_block = get_sb_block(&data);
1913         ext4_fsblk_t logical_sb_block;
1914         unsigned long offset = 0;
1915         unsigned int journal_inum = 0;
1916         unsigned long journal_devnum = 0;
1917         unsigned long def_mount_opts;
1918         struct inode *root;
1919         int ret = -EINVAL;
1920         int blocksize;
1921         int db_count;
1922         int i;
1923         int needs_recovery;
1924         __le32 features;
1925         __u64 blocks_count;
1926         int err;
1927
1928         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1929         if (!sbi)
1930                 return -ENOMEM;
1931         sb->s_fs_info = sbi;
1932         sbi->s_mount_opt = 0;
1933         sbi->s_resuid = EXT4_DEF_RESUID;
1934         sbi->s_resgid = EXT4_DEF_RESGID;
1935         sbi->s_sb_block = sb_block;
1936
1937         unlock_kernel();
1938
1939         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1940         if (!blocksize) {
1941                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1942                 goto out_fail;
1943         }
1944
1945         /*
1946          * The ext4 superblock will not be buffer aligned for other than 1kB
1947          * block sizes.  We need to calculate the offset from buffer start.
1948          */
1949         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1950                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1951                 offset = do_div(logical_sb_block, blocksize);
1952         } else {
1953                 logical_sb_block = sb_block;
1954         }
1955
1956         if (!(bh = sb_bread(sb, logical_sb_block))) {
1957                 printk (KERN_ERR "EXT4-fs: unable to read superblock\n");
1958                 goto out_fail;
1959         }
1960         /*
1961          * Note: s_es must be initialized as soon as possible because
1962          *       some ext4 macro-instructions depend on its value
1963          */
1964         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1965         sbi->s_es = es;
1966         sb->s_magic = le16_to_cpu(es->s_magic);
1967         if (sb->s_magic != EXT4_SUPER_MAGIC)
1968                 goto cantfind_ext4;
1969
1970         /* Set defaults before we parse the mount options */
1971         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1972         if (def_mount_opts & EXT4_DEFM_DEBUG)
1973                 set_opt(sbi->s_mount_opt, DEBUG);
1974         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1975                 set_opt(sbi->s_mount_opt, GRPID);
1976         if (def_mount_opts & EXT4_DEFM_UID16)
1977                 set_opt(sbi->s_mount_opt, NO_UID32);
1978 #ifdef CONFIG_EXT4DEV_FS_XATTR
1979         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1980                 set_opt(sbi->s_mount_opt, XATTR_USER);
1981 #endif
1982 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1983         if (def_mount_opts & EXT4_DEFM_ACL)
1984                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1985 #endif
1986         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1987                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1988         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1989                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1990         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1991                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
1992
1993         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
1994                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1995         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
1996                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
1997         else
1998                 set_opt(sbi->s_mount_opt, ERRORS_RO);
1999
2000         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2001         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2002
2003         set_opt(sbi->s_mount_opt, RESERVATION);
2004         set_opt(sbi->s_mount_opt, BARRIER);
2005
2006         /*
2007          * turn on extents feature by default in ext4 filesystem
2008          * only if feature flag already set by mkfs or tune2fs.
2009          * Use -o noextents to turn it off
2010          */
2011         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2012                 set_opt(sbi->s_mount_opt, EXTENTS);
2013         else
2014                 ext4_warning(sb, __func__,
2015                         "extents feature not enabled on this filesystem, "
2016                         "use tune2fs.\n");
2017         /*
2018          * turn on mballoc code by default in ext4 filesystem
2019          * Use -o nomballoc to turn it off
2020          */
2021         set_opt(sbi->s_mount_opt, MBALLOC);
2022
2023         /*
2024          * enable delayed allocation by default
2025          * Use -o nodelalloc to turn it off
2026          */
2027         set_opt(sbi->s_mount_opt, DELALLOC);
2028
2029
2030         if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
2031                             NULL, 0))
2032                 goto failed_mount;
2033
2034         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2035                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2036
2037         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2038             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2039              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2040              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2041                 printk(KERN_WARNING
2042                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2043                        "running e2fsck is recommended\n");
2044
2045         /*
2046          * Since ext4 is still considered development code, we require
2047          * that the TEST_FILESYS flag in s->flags be set.
2048          */
2049         if (!(le32_to_cpu(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)) {
2050                 printk(KERN_WARNING "EXT4-fs: %s: not marked "
2051                        "OK to use with test code.\n", sb->s_id);
2052                 goto failed_mount;
2053         }
2054
2055         /*
2056          * Check feature flags regardless of the revision level, since we
2057          * previously didn't change the revision level when setting the flags,
2058          * so there is a chance incompat flags are set on a rev 0 filesystem.
2059          */
2060         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2061         if (features) {
2062                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2063                        "unsupported optional features (%x).\n",
2064                        sb->s_id, le32_to_cpu(features));
2065                 goto failed_mount;
2066         }
2067         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2068         if (!(sb->s_flags & MS_RDONLY) && features) {
2069                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2070                        "unsupported optional features (%x).\n",
2071                        sb->s_id, le32_to_cpu(features));
2072                 goto failed_mount;
2073         }
2074         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2075                 /*
2076                  * Large file size enabled file system can only be
2077                  * mount if kernel is build with CONFIG_LSF
2078                  */
2079                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2080                                 !(sb->s_flags & MS_RDONLY)) {
2081                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2082                                         "files cannot be mounted read-write "
2083                                         "without CONFIG_LSF.\n", sb->s_id);
2084                         goto failed_mount;
2085                 }
2086         }
2087         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2088
2089         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2090             blocksize > EXT4_MAX_BLOCK_SIZE) {
2091                 printk(KERN_ERR
2092                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2093                        blocksize, sb->s_id);
2094                 goto failed_mount;
2095         }
2096
2097         if (sb->s_blocksize != blocksize) {
2098
2099                 /* Validate the filesystem blocksize */
2100                 if (!sb_set_blocksize(sb, blocksize)) {
2101                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2102                                         blocksize);
2103                         goto failed_mount;
2104                 }
2105
2106                 brelse (bh);
2107                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2108                 offset = do_div(logical_sb_block, blocksize);
2109                 bh = sb_bread(sb, logical_sb_block);
2110                 if (!bh) {
2111                         printk(KERN_ERR
2112                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2113                         goto failed_mount;
2114                 }
2115                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2116                 sbi->s_es = es;
2117                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2118                         printk (KERN_ERR
2119                                 "EXT4-fs: Magic mismatch, very weird !\n");
2120                         goto failed_mount;
2121                 }
2122         }
2123
2124         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits);
2125         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
2126
2127         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2128                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2129                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2130         } else {
2131                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2132                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2133                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2134                     (!is_power_of_2(sbi->s_inode_size)) ||
2135                     (sbi->s_inode_size > blocksize)) {
2136                         printk (KERN_ERR
2137                                 "EXT4-fs: unsupported inode size: %d\n",
2138                                 sbi->s_inode_size);
2139                         goto failed_mount;
2140                 }
2141                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2142                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2143         }
2144         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2145         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2146                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2147                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2148                     !is_power_of_2(sbi->s_desc_size)) {
2149                         printk(KERN_ERR
2150                                "EXT4-fs: unsupported descriptor size %lu\n",
2151                                sbi->s_desc_size);
2152                         goto failed_mount;
2153                 }
2154         } else
2155                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2156         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2157         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2158         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2159                 goto cantfind_ext4;
2160         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2161         if (sbi->s_inodes_per_block == 0)
2162                 goto cantfind_ext4;
2163         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2164                                         sbi->s_inodes_per_block;
2165         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2166         sbi->s_sbh = bh;
2167         sbi->s_mount_state = le16_to_cpu(es->s_state);
2168         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2169         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2170         for (i=0; i < 4; i++)
2171                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2172         sbi->s_def_hash_version = es->s_def_hash_version;
2173
2174         if (sbi->s_blocks_per_group > blocksize * 8) {
2175                 printk (KERN_ERR
2176                         "EXT4-fs: #blocks per group too big: %lu\n",
2177                         sbi->s_blocks_per_group);
2178                 goto failed_mount;
2179         }
2180         if (sbi->s_inodes_per_group > blocksize * 8) {
2181                 printk (KERN_ERR
2182                         "EXT4-fs: #inodes per group too big: %lu\n",
2183                         sbi->s_inodes_per_group);
2184                 goto failed_mount;
2185         }
2186
2187         if (ext4_blocks_count(es) >
2188                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2189                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2190                         " too large to mount safely\n", sb->s_id);
2191                 if (sizeof(sector_t) < 8)
2192                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2193                                         "enabled\n");
2194                 goto failed_mount;
2195         }
2196
2197         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2198                 goto cantfind_ext4;
2199
2200         /* ensure blocks_count calculation below doesn't sign-extend */
2201         if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
2202             le32_to_cpu(es->s_first_data_block) + 1) {
2203                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
2204                        "first data block %u, blocks per group %lu\n",
2205                         ext4_blocks_count(es),
2206                         le32_to_cpu(es->s_first_data_block),
2207                         EXT4_BLOCKS_PER_GROUP(sb));
2208                 goto failed_mount;
2209         }
2210         blocks_count = (ext4_blocks_count(es) -
2211                         le32_to_cpu(es->s_first_data_block) +
2212                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2213         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2214         sbi->s_groups_count = blocks_count;
2215         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2216                    EXT4_DESC_PER_BLOCK(sb);
2217         sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
2218                                     GFP_KERNEL);
2219         if (sbi->s_group_desc == NULL) {
2220                 printk (KERN_ERR "EXT4-fs: not enough memory\n");
2221                 goto failed_mount;
2222         }
2223
2224         bgl_lock_init(&sbi->s_blockgroup_lock);
2225
2226         for (i = 0; i < db_count; i++) {
2227                 block = descriptor_loc(sb, logical_sb_block, i);
2228                 sbi->s_group_desc[i] = sb_bread(sb, block);
2229                 if (!sbi->s_group_desc[i]) {
2230                         printk (KERN_ERR "EXT4-fs: "
2231                                 "can't read group descriptor %d\n", i);
2232                         db_count = i;
2233                         goto failed_mount2;
2234                 }
2235         }
2236         if (!ext4_check_descriptors (sb)) {
2237                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2238                 goto failed_mount2;
2239         }
2240         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2241                 if (!ext4_fill_flex_info(sb)) {
2242                         printk(KERN_ERR
2243                                "EXT4-fs: unable to initialize "
2244                                "flex_bg meta info!\n");
2245                         goto failed_mount2;
2246                 }
2247
2248         sbi->s_gdb_count = db_count;
2249         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2250         spin_lock_init(&sbi->s_next_gen_lock);
2251
2252         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2253                         ext4_count_free_blocks(sb));
2254         if (!err) {
2255                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2256                                 ext4_count_free_inodes(sb));
2257         }
2258         if (!err) {
2259                 err = percpu_counter_init(&sbi->s_dirs_counter,
2260                                 ext4_count_dirs(sb));
2261         }
2262         if (err) {
2263                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2264                 goto failed_mount3;
2265         }
2266
2267         /* per fileystem reservation list head & lock */
2268         spin_lock_init(&sbi->s_rsv_window_lock);
2269         sbi->s_rsv_window_root = RB_ROOT;
2270         /* Add a single, static dummy reservation to the start of the
2271          * reservation window list --- it gives us a placeholder for
2272          * append-at-start-of-list which makes the allocation logic
2273          * _much_ simpler. */
2274         sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2275         sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2276         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
2277         sbi->s_rsv_window_head.rsv_goal_size = 0;
2278         ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
2279
2280         sbi->s_stripe = ext4_get_stripe_size(sbi);
2281
2282         /*
2283          * set up enough so that it can read an inode
2284          */
2285         sb->s_op = &ext4_sops;
2286         sb->s_export_op = &ext4_export_ops;
2287         sb->s_xattr = ext4_xattr_handlers;
2288 #ifdef CONFIG_QUOTA
2289         sb->s_qcop = &ext4_qctl_operations;
2290         sb->dq_op = &ext4_quota_operations;
2291 #endif
2292         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2293
2294         sb->s_root = NULL;
2295
2296         needs_recovery = (es->s_last_orphan != 0 ||
2297                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2298                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2299
2300         /*
2301          * The first inode we look at is the journal inode.  Don't try
2302          * root first: it may be modified in the journal!
2303          */
2304         if (!test_opt(sb, NOLOAD) &&
2305             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2306                 if (ext4_load_journal(sb, es, journal_devnum))
2307                         goto failed_mount3;
2308                 if (!(sb->s_flags & MS_RDONLY) &&
2309                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2310                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2311                                "ext4_fill_super: Journal transaction "
2312                                "%u is corrupt\n", sb->s_id,
2313                                EXT4_SB(sb)->s_journal->j_failed_commit);
2314                         if (test_opt (sb, ERRORS_RO)) {
2315                                 printk (KERN_CRIT
2316                                         "Mounting filesystem read-only\n");
2317                                 sb->s_flags |= MS_RDONLY;
2318                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2319                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2320                         }
2321                         if (test_opt(sb, ERRORS_PANIC)) {
2322                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2323                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2324                                 ext4_commit_super(sb, es, 1);
2325                                 printk(KERN_CRIT
2326                                        "EXT4-fs (device %s): mount failed\n",
2327                                       sb->s_id);
2328                                 goto failed_mount4;
2329                         }
2330                 }
2331         } else if (journal_inum) {
2332                 if (ext4_create_journal(sb, es, journal_inum))
2333                         goto failed_mount3;
2334         } else {
2335                 if (!silent)
2336                         printk (KERN_ERR
2337                                 "ext4: No journal on filesystem on %s\n",
2338                                 sb->s_id);
2339                 goto failed_mount3;
2340         }
2341
2342         if (ext4_blocks_count(es) > 0xffffffffULL &&
2343             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2344                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2345                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
2346                 goto failed_mount4;
2347         }
2348
2349         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2350                 jbd2_journal_set_features(sbi->s_journal,
2351                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2352                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2353         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2354                 jbd2_journal_set_features(sbi->s_journal,
2355                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2356                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2357                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2358         } else {
2359                 jbd2_journal_clear_features(sbi->s_journal,
2360                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2361                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2362         }
2363
2364         /* We have now updated the journal if required, so we can
2365          * validate the data journaling mode. */
2366         switch (test_opt(sb, DATA_FLAGS)) {
2367         case 0:
2368                 /* No mode set, assume a default based on the journal
2369                  * capabilities: ORDERED_DATA if the journal can
2370                  * cope, else JOURNAL_DATA
2371                  */
2372                 if (jbd2_journal_check_available_features
2373                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2374                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2375                 else
2376                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2377                 break;
2378
2379         case EXT4_MOUNT_ORDERED_DATA:
2380         case EXT4_MOUNT_WRITEBACK_DATA:
2381                 if (!jbd2_journal_check_available_features
2382                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2383                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2384                                "requested data journaling mode\n");
2385                         goto failed_mount4;
2386                 }
2387         default:
2388                 break;
2389         }
2390
2391         if (test_opt(sb, NOBH)) {
2392                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2393                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2394                                 "its supported only with writeback mode\n");
2395                         clear_opt(sbi->s_mount_opt, NOBH);
2396                 }
2397         }
2398         /*
2399          * The jbd2_journal_load will have done any necessary log recovery,
2400          * so we can safely mount the rest of the filesystem now.
2401          */
2402
2403         root = ext4_iget(sb, EXT4_ROOT_INO);
2404         if (IS_ERR(root)) {
2405                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2406                 ret = PTR_ERR(root);
2407                 goto failed_mount4;
2408         }
2409         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2410                 iput(root);
2411                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2412                 goto failed_mount4;
2413         }
2414         sb->s_root = d_alloc_root(root);
2415         if (!sb->s_root) {
2416                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2417                 iput(root);
2418                 ret = -ENOMEM;
2419                 goto failed_mount4;
2420         }
2421
2422         ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY);
2423
2424         /* determine the minimum size of new large inodes, if present */
2425         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2426                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2427                                                      EXT4_GOOD_OLD_INODE_SIZE;
2428                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2429                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2430                         if (sbi->s_want_extra_isize <
2431                             le16_to_cpu(es->s_want_extra_isize))
2432                                 sbi->s_want_extra_isize =
2433                                         le16_to_cpu(es->s_want_extra_isize);
2434                         if (sbi->s_want_extra_isize <
2435                             le16_to_cpu(es->s_min_extra_isize))
2436                                 sbi->s_want_extra_isize =
2437                                         le16_to_cpu(es->s_min_extra_isize);
2438                 }
2439         }
2440         /* Check if enough inode space is available */
2441         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2442                                                         sbi->s_inode_size) {
2443                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2444                                                        EXT4_GOOD_OLD_INODE_SIZE;
2445                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2446                         "available.\n");
2447         }
2448
2449         /*
2450          * akpm: core read_super() calls in here with the superblock locked.
2451          * That deadlocks, because orphan cleanup needs to lock the superblock
2452          * in numerous places.  Here we just pop the lock - it's relatively
2453          * harmless, because we are now ready to accept write_super() requests,
2454          * and aviro says that's the only reason for hanging onto the
2455          * superblock lock.
2456          */
2457         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2458         ext4_orphan_cleanup(sb, es);
2459         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2460         if (needs_recovery)
2461                 printk (KERN_INFO "EXT4-fs: recovery complete.\n");
2462         ext4_mark_recovery_complete(sb, es);
2463         printk (KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
2464                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
2465                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
2466                 "writeback");
2467
2468         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2469                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2470                                 "requested data journaling mode\n");
2471                 clear_opt(sbi->s_mount_opt, DELALLOC);
2472         } else if (test_opt(sb, DELALLOC))
2473                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2474
2475         ext4_ext_init(sb);
2476         ext4_mb_init(sb, needs_recovery);
2477
2478         lock_kernel();
2479         return 0;
2480
2481 cantfind_ext4:
2482         if (!silent)
2483                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2484                        sb->s_id);
2485         goto failed_mount;
2486
2487 failed_mount4:
2488         jbd2_journal_destroy(sbi->s_journal);
2489         sbi->s_journal = NULL;
2490 failed_mount3:
2491         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2492         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2493         percpu_counter_destroy(&sbi->s_dirs_counter);
2494 failed_mount2:
2495         for (i = 0; i < db_count; i++)
2496                 brelse(sbi->s_group_desc[i]);
2497         kfree(sbi->s_group_desc);
2498 failed_mount:
2499 #ifdef CONFIG_QUOTA
2500         for (i = 0; i < MAXQUOTAS; i++)
2501                 kfree(sbi->s_qf_names[i]);
2502 #endif
2503         ext4_blkdev_remove(sbi);
2504         brelse(bh);
2505 out_fail:
2506         sb->s_fs_info = NULL;
2507         kfree(sbi);
2508         lock_kernel();
2509         return ret;
2510 }
2511
2512 /*
2513  * Setup any per-fs journal parameters now.  We'll do this both on
2514  * initial mount, once the journal has been initialised but before we've
2515  * done any recovery; and again on any subsequent remount.
2516  */
2517 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2518 {
2519         struct ext4_sb_info *sbi = EXT4_SB(sb);
2520
2521         if (sbi->s_commit_interval)
2522                 journal->j_commit_interval = sbi->s_commit_interval;
2523         /* We could also set up an ext4-specific default for the commit
2524          * interval here, but for now we'll just fall back to the jbd
2525          * default. */
2526
2527         spin_lock(&journal->j_state_lock);
2528         if (test_opt(sb, BARRIER))
2529                 journal->j_flags |= JBD2_BARRIER;
2530         else
2531                 journal->j_flags &= ~JBD2_BARRIER;
2532         spin_unlock(&journal->j_state_lock);
2533 }
2534
2535 static journal_t *ext4_get_journal(struct super_block *sb,
2536                                    unsigned int journal_inum)
2537 {
2538         struct inode *journal_inode;
2539         journal_t *journal;
2540
2541         /* First, test for the existence of a valid inode on disk.  Bad
2542          * things happen if we iget() an unused inode, as the subsequent
2543          * iput() will try to delete it. */
2544
2545         journal_inode = ext4_iget(sb, journal_inum);
2546         if (IS_ERR(journal_inode)) {
2547                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2548                 return NULL;
2549         }
2550         if (!journal_inode->i_nlink) {
2551                 make_bad_inode(journal_inode);
2552                 iput(journal_inode);
2553                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2554                 return NULL;
2555         }
2556
2557         jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
2558                   journal_inode, journal_inode->i_size);
2559         if (!S_ISREG(journal_inode->i_mode)) {
2560                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2561                 iput(journal_inode);
2562                 return NULL;
2563         }
2564
2565         journal = jbd2_journal_init_inode(journal_inode);
2566         if (!journal) {
2567                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2568                 iput(journal_inode);
2569                 return NULL;
2570         }
2571         journal->j_private = sb;
2572         ext4_init_journal_params(sb, journal);
2573         return journal;
2574 }
2575
2576 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2577                                        dev_t j_dev)
2578 {
2579         struct buffer_head * bh;
2580         journal_t *journal;
2581         ext4_fsblk_t start;
2582         ext4_fsblk_t len;
2583         int hblock, blocksize;
2584         ext4_fsblk_t sb_block;
2585         unsigned long offset;
2586         struct ext4_super_block * es;
2587         struct block_device *bdev;
2588
2589         bdev = ext4_blkdev_get(j_dev);
2590         if (bdev == NULL)
2591                 return NULL;
2592
2593         if (bd_claim(bdev, sb)) {
2594                 printk(KERN_ERR
2595                         "EXT4: failed to claim external journal device.\n");
2596                 blkdev_put(bdev);
2597                 return NULL;
2598         }
2599
2600         blocksize = sb->s_blocksize;
2601         hblock = bdev_hardsect_size(bdev);
2602         if (blocksize < hblock) {
2603                 printk(KERN_ERR
2604                         "EXT4-fs: blocksize too small for journal device.\n");
2605                 goto out_bdev;
2606         }
2607
2608         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2609         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2610         set_blocksize(bdev, blocksize);
2611         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2612                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2613                        "external journal\n");
2614                 goto out_bdev;
2615         }
2616
2617         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2618         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2619             !(le32_to_cpu(es->s_feature_incompat) &
2620               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2621                 printk(KERN_ERR "EXT4-fs: external journal has "
2622                                         "bad superblock\n");
2623                 brelse(bh);
2624                 goto out_bdev;
2625         }
2626
2627         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2628                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2629                 brelse(bh);
2630                 goto out_bdev;
2631         }
2632
2633         len = ext4_blocks_count(es);
2634         start = sb_block + 1;
2635         brelse(bh);     /* we're done with the superblock */
2636
2637         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2638                                         start, len, blocksize);
2639         if (!journal) {
2640                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2641                 goto out_bdev;
2642         }
2643         journal->j_private = sb;
2644         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2645         wait_on_buffer(journal->j_sb_buffer);
2646         if (!buffer_uptodate(journal->j_sb_buffer)) {
2647                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2648                 goto out_journal;
2649         }
2650         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2651                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2652                                         "user (unsupported) - %d\n",
2653                         be32_to_cpu(journal->j_superblock->s_nr_users));
2654                 goto out_journal;
2655         }
2656         EXT4_SB(sb)->journal_bdev = bdev;
2657         ext4_init_journal_params(sb, journal);
2658         return journal;
2659 out_journal:
2660         jbd2_journal_destroy(journal);
2661 out_bdev:
2662         ext4_blkdev_put(bdev);
2663         return NULL;
2664 }
2665
2666 static int ext4_load_journal(struct super_block *sb,
2667                              struct ext4_super_block *es,
2668                              unsigned long journal_devnum)
2669 {
2670         journal_t *journal;
2671         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2672         dev_t journal_dev;
2673         int err = 0;
2674         int really_read_only;
2675
2676         if (journal_devnum &&
2677             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2678                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2679                         "numbers have changed\n");
2680                 journal_dev = new_decode_dev(journal_devnum);
2681         } else
2682                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2683
2684         really_read_only = bdev_read_only(sb->s_bdev);
2685
2686         /*
2687          * Are we loading a blank journal or performing recovery after a
2688          * crash?  For recovery, we need to check in advance whether we
2689          * can get read-write access to the device.
2690          */
2691
2692         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2693                 if (sb->s_flags & MS_RDONLY) {
2694                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2695                                         "required on readonly filesystem.\n");
2696                         if (really_read_only) {
2697                                 printk(KERN_ERR "EXT4-fs: write access "
2698                                         "unavailable, cannot proceed.\n");
2699                                 return -EROFS;
2700                         }
2701                         printk (KERN_INFO "EXT4-fs: write access will "
2702                                         "be enabled during recovery.\n");
2703                 }
2704         }
2705
2706         if (journal_inum && journal_dev) {
2707                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2708                        "and inode journals!\n");
2709                 return -EINVAL;
2710         }
2711
2712         if (journal_inum) {
2713                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2714                         return -EINVAL;
2715         } else {
2716                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2717                         return -EINVAL;
2718         }
2719
2720         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2721                 err = jbd2_journal_update_format(journal);
2722                 if (err)  {
2723                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2724                         jbd2_journal_destroy(journal);
2725                         return err;
2726                 }
2727         }
2728
2729         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2730                 err = jbd2_journal_wipe(journal, !really_read_only);
2731         if (!err)
2732                 err = jbd2_journal_load(journal);
2733
2734         if (err) {
2735                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2736                 jbd2_journal_destroy(journal);
2737                 return err;
2738         }
2739
2740         EXT4_SB(sb)->s_journal = journal;
2741         ext4_clear_journal_err(sb, es);
2742
2743         if (journal_devnum &&
2744             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2745                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2746                 sb->s_dirt = 1;
2747
2748                 /* Make sure we flush the recovery flag to disk. */
2749                 ext4_commit_super(sb, es, 1);
2750         }
2751
2752         return 0;
2753 }
2754
2755 static int ext4_create_journal(struct super_block * sb,
2756                                struct ext4_super_block * es,
2757                                unsigned int journal_inum)
2758 {
2759         journal_t *journal;
2760         int err;
2761
2762         if (sb->s_flags & MS_RDONLY) {
2763                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2764                                 "create journal.\n");
2765                 return -EROFS;
2766         }
2767
2768         journal = ext4_get_journal(sb, journal_inum);
2769         if (!journal)
2770                 return -EINVAL;
2771
2772         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2773                journal_inum);
2774
2775         err = jbd2_journal_create(journal);
2776         if (err) {
2777                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2778                 jbd2_journal_destroy(journal);
2779                 return -EIO;
2780         }
2781
2782         EXT4_SB(sb)->s_journal = journal;
2783
2784         ext4_update_dynamic_rev(sb);
2785         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2786         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2787
2788         es->s_journal_inum = cpu_to_le32(journal_inum);
2789         sb->s_dirt = 1;
2790
2791         /* Make sure we flush the recovery flag to disk. */
2792         ext4_commit_super(sb, es, 1);
2793
2794         return 0;
2795 }
2796
2797 static void ext4_commit_super (struct super_block * sb,
2798                                struct ext4_super_block * es,
2799                                int sync)
2800 {
2801         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2802
2803         if (!sbh)
2804                 return;
2805         es->s_wtime = cpu_to_le32(get_seconds());
2806         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2807         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2808         BUFFER_TRACE(sbh, "marking dirty");
2809         mark_buffer_dirty(sbh);
2810         if (sync)
2811                 sync_dirty_buffer(sbh);
2812 }
2813
2814
2815 /*
2816  * Have we just finished recovery?  If so, and if we are mounting (or
2817  * remounting) the filesystem readonly, then we will end up with a
2818  * consistent fs on disk.  Record that fact.
2819  */
2820 static void ext4_mark_recovery_complete(struct super_block * sb,
2821                                         struct ext4_super_block * es)
2822 {
2823         journal_t *journal = EXT4_SB(sb)->s_journal;
2824
2825         jbd2_journal_lock_updates(journal);
2826         jbd2_journal_flush(journal);
2827         lock_super(sb);
2828         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2829             sb->s_flags & MS_RDONLY) {
2830                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2831                 sb->s_dirt = 0;
2832                 ext4_commit_super(sb, es, 1);
2833         }
2834         unlock_super(sb);
2835         jbd2_journal_unlock_updates(journal);
2836 }
2837
2838 /*
2839  * If we are mounting (or read-write remounting) a filesystem whose journal
2840  * has recorded an error from a previous lifetime, move that error to the
2841  * main filesystem now.
2842  */
2843 static void ext4_clear_journal_err(struct super_block * sb,
2844                                    struct ext4_super_block * es)
2845 {
2846         journal_t *journal;
2847         int j_errno;
2848         const char *errstr;
2849
2850         journal = EXT4_SB(sb)->s_journal;
2851
2852         /*
2853          * Now check for any error status which may have been recorded in the
2854          * journal by a prior ext4_error() or ext4_abort()
2855          */
2856
2857         j_errno = jbd2_journal_errno(journal);
2858         if (j_errno) {
2859                 char nbuf[16];
2860
2861                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2862                 ext4_warning(sb, __func__, "Filesystem error recorded "
2863                              "from previous mount: %s", errstr);
2864                 ext4_warning(sb, __func__, "Marking fs in need of "
2865                              "filesystem check.");
2866
2867                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2868                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2869                 ext4_commit_super (sb, es, 1);
2870
2871                 jbd2_journal_clear_err(journal);
2872         }
2873 }
2874
2875 /*
2876  * Force the running and committing transactions to commit,
2877  * and wait on the commit.
2878  */
2879 int ext4_force_commit(struct super_block *sb)
2880 {
2881         journal_t *journal;
2882         int ret;
2883
2884         if (sb->s_flags & MS_RDONLY)
2885                 return 0;
2886
2887         journal = EXT4_SB(sb)->s_journal;
2888         sb->s_dirt = 0;
2889         ret = ext4_journal_force_commit(journal);
2890         return ret;
2891 }
2892
2893 /*
2894  * Ext4 always journals updates to the superblock itself, so we don't
2895  * have to propagate any other updates to the superblock on disk at this
2896  * point.  Just start an async writeback to get the buffers on their way
2897  * to the disk.
2898  *
2899  * This implicitly triggers the writebehind on sync().
2900  */
2901
2902 static void ext4_write_super (struct super_block * sb)
2903 {
2904         if (mutex_trylock(&sb->s_lock) != 0)
2905                 BUG();
2906         sb->s_dirt = 0;
2907 }
2908
2909 static int ext4_sync_fs(struct super_block *sb, int wait)
2910 {
2911         tid_t target;
2912
2913         sb->s_dirt = 0;
2914         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2915                 if (wait)
2916                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2917         }
2918         return 0;
2919 }
2920
2921 /*
2922  * LVM calls this function before a (read-only) snapshot is created.  This
2923  * gives us a chance to flush the journal completely and mark the fs clean.
2924  */
2925 static void ext4_write_super_lockfs(struct super_block *sb)
2926 {
2927         sb->s_dirt = 0;
2928
2929         if (!(sb->s_flags & MS_RDONLY)) {
2930                 journal_t *journal = EXT4_SB(sb)->s_journal;
2931
2932                 /* Now we set up the journal barrier. */
2933                 jbd2_journal_lock_updates(journal);
2934                 jbd2_journal_flush(journal);
2935
2936                 /* Journal blocked and flushed, clear needs_recovery flag. */
2937                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2938                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2939         }
2940 }
2941
2942 /*
2943  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2944  * flag here, even though the filesystem is not technically dirty yet.
2945  */
2946 static void ext4_unlockfs(struct super_block *sb)
2947 {
2948         if (!(sb->s_flags & MS_RDONLY)) {
2949                 lock_super(sb);
2950                 /* Reser the needs_recovery flag before the fs is unlocked. */
2951                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2952                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2953                 unlock_super(sb);
2954                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2955         }
2956 }
2957
2958 static int ext4_remount (struct super_block * sb, int * flags, char * data)
2959 {
2960         struct ext4_super_block * es;
2961         struct ext4_sb_info *sbi = EXT4_SB(sb);
2962         ext4_fsblk_t n_blocks_count = 0;
2963         unsigned long old_sb_flags;
2964         struct ext4_mount_options old_opts;
2965         ext4_group_t g;
2966         int err;
2967 #ifdef CONFIG_QUOTA
2968         int i;
2969 #endif
2970
2971         /* Store the original options */
2972         old_sb_flags = sb->s_flags;
2973         old_opts.s_mount_opt = sbi->s_mount_opt;
2974         old_opts.s_resuid = sbi->s_resuid;
2975         old_opts.s_resgid = sbi->s_resgid;
2976         old_opts.s_commit_interval = sbi->s_commit_interval;
2977 #ifdef CONFIG_QUOTA
2978         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
2979         for (i = 0; i < MAXQUOTAS; i++)
2980                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
2981 #endif
2982
2983         /*
2984          * Allow the "check" option to be passed as a remount option.
2985          */
2986         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
2987                 err = -EINVAL;
2988                 goto restore_opts;
2989         }
2990
2991         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
2992                 ext4_abort(sb, __func__, "Abort forced by user");
2993
2994         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2995                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2996
2997         es = sbi->s_es;
2998
2999         ext4_init_journal_params(sb, sbi->s_journal);
3000
3001         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3002                 n_blocks_count > ext4_blocks_count(es)) {
3003                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3004                         err = -EROFS;
3005                         goto restore_opts;
3006                 }
3007
3008                 if (*flags & MS_RDONLY) {
3009                         /*
3010                          * First of all, the unconditional stuff we have to do
3011                          * to disable replay of the journal when we next remount
3012                          */
3013                         sb->s_flags |= MS_RDONLY;
3014
3015                         /*
3016                          * OK, test if we are remounting a valid rw partition
3017                          * readonly, and if so set the rdonly flag and then
3018                          * mark the partition as valid again.
3019                          */
3020                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3021                             (sbi->s_mount_state & EXT4_VALID_FS))
3022                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3023
3024                         /*
3025                          * We have to unlock super so that we can wait for
3026                          * transactions.
3027                          */
3028                         unlock_super(sb);
3029                         ext4_mark_recovery_complete(sb, es);
3030                         lock_super(sb);
3031                 } else {
3032                         __le32 ret;
3033                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3034                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3035                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3036                                        "remount RDWR because of unsupported "
3037                                        "optional features (%x).\n",
3038                                        sb->s_id, le32_to_cpu(ret));
3039                                 err = -EROFS;
3040                                 goto restore_opts;
3041                         }
3042
3043                         /*
3044                          * Make sure the group descriptor checksums
3045                          * are sane.  If they aren't, refuse to
3046                          * remount r/w.
3047                          */
3048                         for (g = 0; g < sbi->s_groups_count; g++) {
3049                                 struct ext4_group_desc *gdp =
3050                                         ext4_get_group_desc(sb, g, NULL);
3051
3052                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3053                                         printk(KERN_ERR
3054                "EXT4-fs: ext4_remount: "
3055                 "Checksum for group %lu failed (%u!=%u)\n",
3056                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3057                                                le16_to_cpu(gdp->bg_checksum));
3058                                         err = -EINVAL;
3059                                         goto restore_opts;
3060                                 }
3061                         }
3062
3063                         /*
3064                          * If we have an unprocessed orphan list hanging
3065                          * around from a previously readonly bdev mount,
3066                          * require a full umount/remount for now.
3067                          */
3068                         if (es->s_last_orphan) {
3069                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3070                                        "remount RDWR because of unprocessed "
3071                                        "orphan inode list.  Please "
3072                                        "umount/remount instead.\n",
3073                                        sb->s_id);
3074                                 err = -EINVAL;
3075                                 goto restore_opts;
3076                         }
3077
3078                         /*
3079                          * Mounting a RDONLY partition read-write, so reread
3080                          * and store the current valid flag.  (It may have
3081                          * been changed by e2fsck since we originally mounted
3082                          * the partition.)
3083                          */
3084                         ext4_clear_journal_err(sb, es);
3085                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3086                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3087                                 goto restore_opts;
3088                         if (!ext4_setup_super (sb, es, 0))
3089                                 sb->s_flags &= ~MS_RDONLY;
3090                 }
3091         }
3092 #ifdef CONFIG_QUOTA
3093         /* Release old quota file names */
3094         for (i = 0; i < MAXQUOTAS; i++)
3095                 if (old_opts.s_qf_names[i] &&
3096                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3097                         kfree(old_opts.s_qf_names[i]);
3098 #endif
3099         return 0;
3100 restore_opts:
3101         sb->s_flags = old_sb_flags;
3102         sbi->s_mount_opt = old_opts.s_mount_opt;
3103         sbi->s_resuid = old_opts.s_resuid;
3104         sbi->s_resgid = old_opts.s_resgid;
3105         sbi->s_commit_interval = old_opts.s_commit_interval;
3106 #ifdef CONFIG_QUOTA
3107         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3108         for (i = 0; i < MAXQUOTAS; i++) {
3109                 if (sbi->s_qf_names[i] &&
3110                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3111                         kfree(sbi->s_qf_names[i]);
3112                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3113         }
3114 #endif
3115         return err;
3116 }
3117
3118 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
3119 {
3120         struct super_block *sb = dentry->d_sb;
3121         struct ext4_sb_info *sbi = EXT4_SB(sb);
3122         struct ext4_super_block *es = sbi->s_es;
3123         u64 fsid;
3124
3125         if (test_opt(sb, MINIX_DF)) {
3126                 sbi->s_overhead_last = 0;
3127         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3128                 ext4_group_t ngroups = sbi->s_groups_count, i;
3129                 ext4_fsblk_t overhead = 0;
3130                 smp_rmb();
3131
3132                 /*
3133                  * Compute the overhead (FS structures).  This is constant
3134                  * for a given filesystem unless the number of block groups
3135                  * changes so we cache the previous value until it does.
3136                  */
3137
3138                 /*
3139                  * All of the blocks before first_data_block are
3140                  * overhead
3141                  */
3142                 overhead = le32_to_cpu(es->s_first_data_block);
3143
3144                 /*
3145                  * Add the overhead attributed to the superblock and
3146                  * block group descriptors.  If the sparse superblocks
3147                  * feature is turned on, then not all groups have this.
3148                  */
3149                 for (i = 0; i < ngroups; i++) {
3150                         overhead += ext4_bg_has_super(sb, i) +
3151                                 ext4_bg_num_gdb(sb, i);
3152                         cond_resched();
3153                 }
3154
3155                 /*
3156                  * Every block group has an inode bitmap, a block
3157                  * bitmap, and an inode table.
3158                  */
3159                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3160                 sbi->s_overhead_last = overhead;
3161                 smp_wmb();
3162                 sbi->s_blocks_last = ext4_blocks_count(es);
3163         }
3164
3165         buf->f_type = EXT4_SUPER_MAGIC;
3166         buf->f_bsize = sb->s_blocksize;
3167         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3168         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter);
3169         ext4_free_blocks_count_set(es, buf->f_bfree);
3170         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3171         if (buf->f_bfree < ext4_r_blocks_count(es))
3172                 buf->f_bavail = 0;
3173         buf->f_files = le32_to_cpu(es->s_inodes_count);
3174         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3175         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3176         buf->f_namelen = EXT4_NAME_LEN;
3177         fsid = le64_to_cpup((void *)es->s_uuid) ^
3178                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3179         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3180         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3181         return 0;
3182 }
3183
3184 /* Helper function for writing quotas on sync - we need to start transaction before quota file
3185  * is locked for write. Otherwise the are possible deadlocks:
3186  * Process 1                         Process 2
3187  * ext4_create()                     quota_sync()
3188  *   jbd2_journal_start()                   write_dquot()
3189  *   DQUOT_INIT()                        down(dqio_mutex)
3190  *     down(dqio_mutex)                    jbd2_journal_start()
3191  *
3192  */
3193
3194 #ifdef CONFIG_QUOTA
3195
3196 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3197 {
3198         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3199 }
3200
3201 static int ext4_dquot_initialize(struct inode *inode, int type)
3202 {
3203         handle_t *handle;
3204         int ret, err;
3205
3206         /* We may create quota structure so we need to reserve enough blocks */
3207         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
3208         if (IS_ERR(handle))
3209                 return PTR_ERR(handle);
3210         ret = dquot_initialize(inode, type);
3211         err = ext4_journal_stop(handle);
3212         if (!ret)
3213                 ret = err;
3214         return ret;
3215 }
3216
3217 static int ext4_dquot_drop(struct inode *inode)
3218 {
3219         handle_t *handle;
3220         int ret, err;
3221
3222         /* We may delete quota structure so we need to reserve enough blocks */
3223         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
3224         if (IS_ERR(handle)) {
3225                 /*
3226                  * We call dquot_drop() anyway to at least release references
3227                  * to quota structures so that umount does not hang.
3228                  */
3229                 dquot_drop(inode);
3230                 return PTR_ERR(handle);
3231         }
3232         ret = dquot_drop(inode);
3233         err = ext4_journal_stop(handle);
3234         if (!ret)
3235                 ret = err;
3236         return ret;
3237 }
3238
3239 static int ext4_write_dquot(struct dquot *dquot)
3240 {
3241         int ret, err;
3242         handle_t *handle;
3243         struct inode *inode;
3244
3245         inode = dquot_to_inode(dquot);
3246         handle = ext4_journal_start(inode,
3247                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3248         if (IS_ERR(handle))
3249                 return PTR_ERR(handle);
3250         ret = dquot_commit(dquot);
3251         err = ext4_journal_stop(handle);
3252         if (!ret)
3253                 ret = err;
3254         return ret;
3255 }
3256
3257 static int ext4_acquire_dquot(struct dquot *dquot)
3258 {
3259         int ret, err;
3260         handle_t *handle;
3261
3262         handle = ext4_journal_start(dquot_to_inode(dquot),
3263                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3264         if (IS_ERR(handle))
3265                 return PTR_ERR(handle);
3266         ret = dquot_acquire(dquot);
3267         err = ext4_journal_stop(handle);
3268         if (!ret)
3269                 ret = err;
3270         return ret;
3271 }
3272
3273 static int ext4_release_dquot(struct dquot *dquot)
3274 {
3275         int ret, err;
3276         handle_t *handle;
3277
3278         handle = ext4_journal_start(dquot_to_inode(dquot),
3279                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3280         if (IS_ERR(handle)) {
3281                 /* Release dquot anyway to avoid endless cycle in dqput() */
3282                 dquot_release(dquot);
3283                 return PTR_ERR(handle);
3284         }
3285         ret = dquot_release(dquot);
3286         err = ext4_journal_stop(handle);
3287         if (!ret)
3288                 ret = err;
3289         return ret;
3290 }
3291
3292 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3293 {
3294         /* Are we journaling quotas? */
3295         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3296             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3297                 dquot_mark_dquot_dirty(dquot);
3298                 return ext4_write_dquot(dquot);
3299         } else {
3300                 return dquot_mark_dquot_dirty(dquot);
3301         }
3302 }
3303
3304 static int ext4_write_info(struct super_block *sb, int type)
3305 {
3306         int ret, err;
3307         handle_t *handle;
3308
3309         /* Data block + inode block */
3310         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3311         if (IS_ERR(handle))
3312                 return PTR_ERR(handle);
3313         ret = dquot_commit_info(sb, type);
3314         err = ext4_journal_stop(handle);
3315         if (!ret)
3316                 ret = err;
3317         return ret;
3318 }
3319
3320 /*
3321  * Turn on quotas during mount time - we need to find
3322  * the quota file and such...
3323  */
3324 static int ext4_quota_on_mount(struct super_block *sb, int type)
3325 {
3326         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3327                         EXT4_SB(sb)->s_jquota_fmt, type);
3328 }
3329
3330 /*
3331  * Standard function to be called on quota_on
3332  */
3333 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3334                          char *path, int remount)
3335 {
3336         int err;
3337         struct nameidata nd;
3338
3339         if (!test_opt(sb, QUOTA))
3340                 return -EINVAL;
3341         /* When remounting, no checks are needed and in fact, path is NULL */
3342         if (remount)
3343                 return vfs_quota_on(sb, type, format_id, path, remount);
3344
3345         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
3346         if (err)
3347                 return err;
3348
3349         /* Quotafile not on the same filesystem? */
3350         if (nd.path.mnt->mnt_sb != sb) {
3351                 path_put(&nd.path);
3352                 return -EXDEV;
3353         }
3354         /* Journaling quota? */
3355         if (EXT4_SB(sb)->s_qf_names[type]) {
3356                 /* Quotafile not of fs root? */
3357                 if (nd.path.dentry->d_parent->d_inode != sb->s_root->d_inode)
3358                         printk(KERN_WARNING
3359                                 "EXT4-fs: Quota file not on filesystem root. "
3360                                 "Journaled quota will not work.\n");
3361         }
3362
3363         /*
3364          * When we journal data on quota file, we have to flush journal to see
3365          * all updates to the file when we bypass pagecache...
3366          */
3367         if (ext4_should_journal_data(nd.path.dentry->d_inode)) {
3368                 /*
3369                  * We don't need to lock updates but journal_flush() could
3370                  * otherwise be livelocked...
3371                  */
3372                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3373                 jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3374                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3375         }
3376
3377         path_put(&nd.path);
3378         return vfs_quota_on(sb, type, format_id, path, remount);
3379 }
3380
3381 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3382  * acquiring the locks... As quota files are never truncated and quota code
3383  * itself serializes the operations (and noone else should touch the files)
3384  * we don't have to be afraid of races */
3385 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3386                                size_t len, loff_t off)
3387 {
3388         struct inode *inode = sb_dqopt(sb)->files[type];
3389         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3390         int err = 0;
3391         int offset = off & (sb->s_blocksize - 1);
3392         int tocopy;
3393         size_t toread;
3394         struct buffer_head *bh;
3395         loff_t i_size = i_size_read(inode);
3396
3397         if (off > i_size)
3398                 return 0;
3399         if (off+len > i_size)
3400                 len = i_size-off;
3401         toread = len;
3402         while (toread > 0) {
3403                 tocopy = sb->s_blocksize - offset < toread ?
3404                                 sb->s_blocksize - offset : toread;
3405                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3406                 if (err)
3407                         return err;
3408                 if (!bh)        /* A hole? */
3409                         memset(data, 0, tocopy);
3410                 else
3411                         memcpy(data, bh->b_data+offset, tocopy);
3412                 brelse(bh);
3413                 offset = 0;
3414                 toread -= tocopy;
3415                 data += tocopy;
3416                 blk++;
3417         }
3418         return len;
3419 }
3420
3421 /* Write to quotafile (we know the transaction is already started and has
3422  * enough credits) */
3423 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3424                                 const char *data, size_t len, loff_t off)
3425 {
3426         struct inode *inode = sb_dqopt(sb)->files[type];
3427         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3428         int err = 0;
3429         int offset = off & (sb->s_blocksize - 1);
3430         int tocopy;
3431         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3432         size_t towrite = len;
3433         struct buffer_head *bh;
3434         handle_t *handle = journal_current_handle();
3435
3436         if (!handle) {
3437                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%Lu, len=%Lu)"
3438                         " cancelled because transaction is not started.\n",
3439                         (unsigned long long)off, (unsigned long long)len);
3440                 return -EIO;
3441         }
3442         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3443         while (towrite > 0) {
3444                 tocopy = sb->s_blocksize - offset < towrite ?
3445                                 sb->s_blocksize - offset : towrite;
3446                 bh = ext4_bread(handle, inode, blk, 1, &err);
3447                 if (!bh)
3448                         goto out;
3449                 if (journal_quota) {
3450                         err = ext4_journal_get_write_access(handle, bh);
3451                         if (err) {
3452                                 brelse(bh);
3453                                 goto out;
3454                         }
3455                 }
3456                 lock_buffer(bh);
3457                 memcpy(bh->b_data+offset, data, tocopy);
3458                 flush_dcache_page(bh->b_page);
3459                 unlock_buffer(bh);
3460                 if (journal_quota)
3461                         err = ext4_journal_dirty_metadata(handle, bh);
3462                 else {
3463                         /* Always do at least ordered writes for quotas */
3464                         err = ext4_jbd2_file_inode(handle, inode);
3465                         mark_buffer_dirty(bh);
3466                 }
3467                 brelse(bh);
3468                 if (err)
3469                         goto out;
3470                 offset = 0;
3471                 towrite -= tocopy;
3472                 data += tocopy;
3473                 blk++;
3474         }
3475 out:
3476         if (len == towrite) {
3477                 mutex_unlock(&inode->i_mutex);
3478                 return err;
3479         }
3480         if (inode->i_size < off+len-towrite) {
3481                 i_size_write(inode, off+len-towrite);
3482                 EXT4_I(inode)->i_disksize = inode->i_size;
3483         }
3484         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3485         ext4_mark_inode_dirty(handle, inode);
3486         mutex_unlock(&inode->i_mutex);
3487         return len - towrite;
3488 }
3489
3490 #endif
3491
3492 static int ext4_get_sb(struct file_system_type *fs_type,
3493         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3494 {
3495         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3496 }
3497
3498 static struct file_system_type ext4dev_fs_type = {
3499         .owner          = THIS_MODULE,
3500         .name           = "ext4dev",
3501         .get_sb         = ext4_get_sb,
3502         .kill_sb        = kill_block_super,
3503         .fs_flags       = FS_REQUIRES_DEV,
3504 };
3505
3506 static int __init init_ext4_fs(void)
3507 {
3508         int err;
3509
3510         err = init_ext4_mballoc();
3511         if (err)
3512                 return err;
3513
3514         err = init_ext4_xattr();
3515         if (err)
3516                 goto out2;
3517         err = init_inodecache();
3518         if (err)
3519                 goto out1;
3520         err = register_filesystem(&ext4dev_fs_type);
3521         if (err)
3522                 goto out;
3523         return 0;
3524 out:
3525         destroy_inodecache();
3526 out1:
3527         exit_ext4_xattr();
3528 out2:
3529         exit_ext4_mballoc();
3530         return err;
3531 }
3532
3533 static void __exit exit_ext4_fs(void)
3534 {
3535         unregister_filesystem(&ext4dev_fs_type);
3536         destroy_inodecache();
3537         exit_ext4_xattr();
3538         exit_ext4_mballoc();
3539 }
3540
3541 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
3542 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
3543 MODULE_LICENSE("GPL");
3544 module_init(init_ext4_fs)
3545 module_exit(exit_ext4_fs)