Pileus Git - ~andy/linux/blob - 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/proc_fs.h>
  38 #include <linux/marker.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <asm/uaccess.h>
  42
  43 #include "ext4.h"
  44 #include "ext4_jbd2.h"
  45 #include "xattr.h"
  46 #include "acl.h"
  47 #include "namei.h"
  48 #include "group.h"
  49
  50 struct proc_dir_entry *ext4_proc_root;
  51
  52 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  53                              unsigned long journal_devnum);
  54 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  55                                unsigned int);
  56 static void ext4_commit_super(struct super_block *sb,
  57                               struct ext4_super_block *es, int sync);
  58 static void ext4_mark_recovery_complete(struct super_block *sb,
  59                                         struct ext4_super_block *es);
  60 static void ext4_clear_journal_err(struct super_block *sb,
  61                                    struct ext4_super_block *es);
  62 static int ext4_sync_fs(struct super_block *sb, int wait);
  63 static const char *ext4_decode_error(struct super_block *sb, int errno,
  64                                      char nbuf[16]);
  65 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  66 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  67 static void ext4_unlockfs(struct super_block *sb);
  68 static void ext4_write_super(struct super_block *sb);
  69 static void ext4_write_super_lockfs(struct super_block *sb);
  70
  71
  72 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  73                                struct ext4_group_desc *bg)
  74 {
  75         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  76                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  77                 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  78 }
  79
  80 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  81                                struct ext4_group_desc *bg)
  82 {
  83         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  84                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  85                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  86 }
  87
  88 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  89                               struct ext4_group_desc *bg)
  90 {
  91         return le32_to_cpu(bg->bg_inode_table_lo) |
  92                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  93                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  94 }
  95
  96 void ext4_block_bitmap_set(struct super_block *sb,
  97                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
  98 {
  99         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 100         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 101                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 102 }
 103
 104 void ext4_inode_bitmap_set(struct super_block *sb,
 105                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 106 {
 107         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 108         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 109                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 110 }
 111
 112 void ext4_inode_table_set(struct super_block *sb,
 113                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 114 {
 115         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 116         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 117                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 118 }
 119
 120 /*
 121  * Wrappers for jbd2_journal_start/end.
 122  *
 123  * The only special thing we need to do here is to make sure that all
 124  * journal_end calls result in the superblock being marked dirty, so
 125  * that sync() will call the filesystem's write_super callback if
 126  * appropriate.
 127  */
 128 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 129 {
 130         journal_t *journal;
 131
 132         if (sb->s_flags & MS_RDONLY)
 133                 return ERR_PTR(-EROFS);
 134
 135         /* Special case here: if the journal has aborted behind our
 136          * backs (eg. EIO in the commit thread), then we still need to
 137          * take the FS itself readonly cleanly. */
 138         journal = EXT4_SB(sb)->s_journal;
 139         if (journal) {
 140                 if (is_journal_aborted(journal)) {
 141                         ext4_abort(sb, __func__,
 142                                    "Detected aborted journal");
 143                         return ERR_PTR(-EROFS);
 144                 }
 145                 return jbd2_journal_start(journal, nblocks);
 146         }
 147         /*
 148          * We're not journaling, return the appropriate indication.
 149          */
 150         current->journal_info = EXT4_NOJOURNAL_HANDLE;
 151         return current->journal_info;
 152 }
 153
 154 /*
 155  * The only special thing we need to do here is to make sure that all
 156  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 157  * that sync() will call the filesystem's write_super callback if
 158  * appropriate.
 159  */
 160 int __ext4_journal_stop(const char *where, handle_t *handle)
 161 {
 162         struct super_block *sb;
 163         int err;
 164         int rc;
 165
 166         if (!ext4_handle_valid(handle)) {
 167                 /*
 168                  * Do this here since we don't call jbd2_journal_stop() in
 169                  * no-journal mode.
 170                  */
 171                 current->journal_info = NULL;
 172                 return 0;
 173         }
 174         sb = handle->h_transaction->t_journal->j_private;
 175         err = handle->h_err;
 176         rc = jbd2_journal_stop(handle);
 177
 178         if (!err)
 179                 err = rc;
 180         if (err)
 181                 __ext4_std_error(sb, where, err);
 182         return err;
 183 }
 184
 185 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 186                 struct buffer_head *bh, handle_t *handle, int err)
 187 {
 188         char nbuf[16];
 189         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 190
 191         BUG_ON(!ext4_handle_valid(handle));
 192
 193         if (bh)
 194                 BUFFER_TRACE(bh, "abort");
 195
 196         if (!handle->h_err)
 197                 handle->h_err = err;
 198
 199         if (is_handle_aborted(handle))
 200                 return;
 201
 202         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 203                caller, errstr, err_fn);
 204
 205         jbd2_journal_abort_handle(handle);
 206 }
 207
 208 /* Deal with the reporting of failure conditions on a filesystem such as
 209  * inconsistencies detected or read IO failures.
 210  *
 211  * On ext2, we can store the error state of the filesystem in the
 212  * superblock.  That is not possible on ext4, because we may have other
 213  * write ordering constraints on the superblock which prevent us from
 214  * writing it out straight away; and given that the journal is about to
 215  * be aborted, we can't rely on the current, or future, transactions to
 216  * write out the superblock safely.
 217  *
 218  * We'll just use the jbd2_journal_abort() error code to record an error in
 219  * the journal instead.  On recovery, the journal will compain about
 220  * that error until we've noted it down and cleared it.
 221  */
 222
 223 static void ext4_handle_error(struct super_block *sb)
 224 {
 225         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 226
 227         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 228         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 229
 230         if (sb->s_flags & MS_RDONLY)
 231                 return;
 232
 233         if (!test_opt(sb, ERRORS_CONT)) {
 234                 journal_t *journal = EXT4_SB(sb)->s_journal;
 235
 236                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 237                 if (journal)
 238                         jbd2_journal_abort(journal, -EIO);
 239         }
 240         if (test_opt(sb, ERRORS_RO)) {
 241                 printk(KERN_CRIT "Remounting filesystem read-only\n");
 242                 sb->s_flags |= MS_RDONLY;
 243         }
 244         ext4_commit_super(sb, es, 1);
 245         if (test_opt(sb, ERRORS_PANIC))
 246                 panic("EXT4-fs (device %s): panic forced after error\n",
 247                         sb->s_id);
 248 }
 249
 250 void ext4_error(struct super_block *sb, const char *function,
 251                 const char *fmt, ...)
 252 {
 253         va_list args;
 254
 255         va_start(args, fmt);
 256         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 257         vprintk(fmt, args);
 258         printk("\n");
 259         va_end(args);
 260
 261         ext4_handle_error(sb);
 262 }
 263
 264 static const char *ext4_decode_error(struct super_block *sb, int errno,
 265                                      char nbuf[16])
 266 {
 267         char *errstr = NULL;
 268
 269         switch (errno) {
 270         case -EIO:
 271                 errstr = "IO failure";
 272                 break;
 273         case -ENOMEM:
 274                 errstr = "Out of memory";
 275                 break;
 276         case -EROFS:
 277                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 278                         errstr = "Journal has aborted";
 279                 else
 280                         errstr = "Readonly filesystem";
 281                 break;
 282         default:
 283                 /* If the caller passed in an extra buffer for unknown
 284                  * errors, textualise them now.  Else we just return
 285                  * NULL. */
 286                 if (nbuf) {
 287                         /* Check for truncated error codes... */
 288                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 289                                 errstr = nbuf;
 290                 }
 291                 break;
 292         }
 293
 294         return errstr;
 295 }
 296
 297 /* __ext4_std_error decodes expected errors from journaling functions
 298  * automatically and invokes the appropriate error response.  */
 299
 300 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 301 {
 302         char nbuf[16];
 303         const char *errstr;
 304
 305         /* Special case: if the error is EROFS, and we're not already
 306          * inside a transaction, then there's really no point in logging
 307          * an error. */
 308         if (errno == -EROFS && journal_current_handle() == NULL &&
 309             (sb->s_flags & MS_RDONLY))
 310                 return;
 311
 312         errstr = ext4_decode_error(sb, errno, nbuf);
 313         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 314                sb->s_id, function, errstr);
 315
 316         ext4_handle_error(sb);
 317 }
 318
 319 /*
 320  * ext4_abort is a much stronger failure handler than ext4_error.  The
 321  * abort function may be used to deal with unrecoverable failures such
 322  * as journal IO errors or ENOMEM at a critical moment in log management.
 323  *
 324  * We unconditionally force the filesystem into an ABORT|READONLY state,
 325  * unless the error response on the fs has been set to panic in which
 326  * case we take the easy way out and panic immediately.
 327  */
 328
 329 void ext4_abort(struct super_block *sb, const char *function,
 330                 const char *fmt, ...)
 331 {
 332         va_list args;
 333
 334         printk(KERN_CRIT "ext4_abort called.\n");
 335
 336         va_start(args, fmt);
 337         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 338         vprintk(fmt, args);
 339         printk("\n");
 340         va_end(args);
 341
 342         if (test_opt(sb, ERRORS_PANIC))
 343                 panic("EXT4-fs panic from previous error\n");
 344
 345         if (sb->s_flags & MS_RDONLY)
 346                 return;
 347
 348         printk(KERN_CRIT "Remounting filesystem read-only\n");
 349         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 350         sb->s_flags |= MS_RDONLY;
 351         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 352         if (EXT4_SB(sb)->s_journal)
 353                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 354 }
 355
 356 void ext4_warning(struct super_block *sb, const char *function,
 357                   const char *fmt, ...)
 358 {
 359         va_list args;
 360
 361         va_start(args, fmt);
 362         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 363                sb->s_id, function);
 364         vprintk(fmt, args);
 365         printk("\n");
 366         va_end(args);
 367 }
 368
 369 void ext4_update_dynamic_rev(struct super_block *sb)
 370 {
 371         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 372
 373         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 374                 return;
 375
 376         ext4_warning(sb, __func__,
 377                      "updating to rev %d because of new feature flag, "
 378                      "running e2fsck is recommended",
 379                      EXT4_DYNAMIC_REV);
 380
 381         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 382         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 383         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 384         /* leave es->s_feature_*compat flags alone */
 385         /* es->s_uuid will be set by e2fsck if empty */
 386
 387         /*
 388          * The rest of the superblock fields should be zero, and if not it
 389          * means they are likely already in use, so leave them alone.  We
 390          * can leave it up to e2fsck to clean up any inconsistencies there.
 391          */
 392 }
 393
 394 /*
 395  * Open the external journal device
 396  */
 397 static struct block_device *ext4_blkdev_get(dev_t dev)
 398 {
 399         struct block_device *bdev;
 400         char b[BDEVNAME_SIZE];
 401
 402         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 403         if (IS_ERR(bdev))
 404                 goto fail;
 405         return bdev;
 406
 407 fail:
 408         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 409                         __bdevname(dev, b), PTR_ERR(bdev));
 410         return NULL;
 411 }
 412
 413 /*
 414  * Release the journal device
 415  */
 416 static int ext4_blkdev_put(struct block_device *bdev)
 417 {
 418         bd_release(bdev);
 419         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 420 }
 421
 422 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 423 {
 424         struct block_device *bdev;
 425         int ret = -ENODEV;
 426
 427         bdev = sbi->journal_bdev;
 428         if (bdev) {
 429                 ret = ext4_blkdev_put(bdev);
 430                 sbi->journal_bdev = NULL;
 431         }
 432         return ret;
 433 }
 434
 435 static inline struct inode *orphan_list_entry(struct list_head *l)
 436 {
 437         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 438 }
 439
 440 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 441 {
 442         struct list_head *l;
 443
 444         printk(KERN_ERR "sb orphan head is %d\n",
 445                le32_to_cpu(sbi->s_es->s_last_orphan));
 446
 447         printk(KERN_ERR "sb_info orphan list:\n");
 448         list_for_each(l, &sbi->s_orphan) {
 449                 struct inode *inode = orphan_list_entry(l);
 450                 printk(KERN_ERR "  "
 451                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 452                        inode->i_sb->s_id, inode->i_ino, inode,
 453                        inode->i_mode, inode->i_nlink,
 454                        NEXT_ORPHAN(inode));
 455         }
 456 }
 457
 458 static void ext4_put_super(struct super_block *sb)
 459 {
 460         struct ext4_sb_info *sbi = EXT4_SB(sb);
 461         struct ext4_super_block *es = sbi->s_es;
 462         int i, err;
 463
 464         ext4_mb_release(sb);
 465         ext4_ext_release(sb);
 466         ext4_xattr_put_super(sb);
 467         if (sbi->s_journal) {
 468                 err = jbd2_journal_destroy(sbi->s_journal);
 469                 sbi->s_journal = NULL;
 470                 if (err < 0)
 471                         ext4_abort(sb, __func__,
 472                                    "Couldn't clean up the journal");
 473         }
 474         if (!(sb->s_flags & MS_RDONLY)) {
 475                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 476                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 477                 ext4_commit_super(sb, es, 1);
 478         }
 479         if (sbi->s_proc) {
 480                 remove_proc_entry("inode_readahead_blks", sbi->s_proc);
 481                 remove_proc_entry(sb->s_id, ext4_proc_root);
 482         }
 483
 484         for (i = 0; i < sbi->s_gdb_count; i++)
 485                 brelse(sbi->s_group_desc[i]);
 486         kfree(sbi->s_group_desc);
 487         kfree(sbi->s_flex_groups);
 488         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 489         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 490         percpu_counter_destroy(&sbi->s_dirs_counter);
 491         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 492         brelse(sbi->s_sbh);
 493 #ifdef CONFIG_QUOTA
 494         for (i = 0; i < MAXQUOTAS; i++)
 495                 kfree(sbi->s_qf_names[i]);
 496 #endif
 497
 498         /* Debugging code just in case the in-memory inode orphan list
 499          * isn't empty.  The on-disk one can be non-empty if we've
 500          * detected an error and taken the fs readonly, but the
 501          * in-memory list had better be clean by this point. */
 502         if (!list_empty(&sbi->s_orphan))
 503                 dump_orphan_list(sb, sbi);
 504         J_ASSERT(list_empty(&sbi->s_orphan));
 505
 506         invalidate_bdev(sb->s_bdev);
 507         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 508                 /*
 509                  * Invalidate the journal device's buffers.  We don't want them
 510                  * floating about in memory - the physical journal device may
 511                  * hotswapped, and it breaks the `ro-after' testing code.
 512                  */
 513                 sync_blockdev(sbi->journal_bdev);
 514                 invalidate_bdev(sbi->journal_bdev);
 515                 ext4_blkdev_remove(sbi);
 516         }
 517         sb->s_fs_info = NULL;
 518         kfree(sbi);
 519         return;
 520 }
 521
 522 static struct kmem_cache *ext4_inode_cachep;
 523
 524 /*
 525  * Called inside transaction, so use GFP_NOFS
 526  */
 527 static struct inode *ext4_alloc_inode(struct super_block *sb)
 528 {
 529         struct ext4_inode_info *ei;
 530
 531         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 532         if (!ei)
 533                 return NULL;
 534 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 535         ei->i_acl = EXT4_ACL_NOT_CACHED;
 536         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 537 #endif
 538         ei->vfs_inode.i_version = 1;
 539         ei->vfs_inode.i_data.writeback_index = 0;
 540         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 541         INIT_LIST_HEAD(&ei->i_prealloc_list);
 542         spin_lock_init(&ei->i_prealloc_lock);
 543         /*
 544          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 545          * therefore it can be null here.  Don't check it, just initialize
 546          * jinode.
 547          */
 548         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 549         ei->i_reserved_data_blocks = 0;
 550         ei->i_reserved_meta_blocks = 0;
 551         ei->i_allocated_meta_blocks = 0;
 552         ei->i_delalloc_reserved_flag = 0;
 553         spin_lock_init(&(ei->i_block_reservation_lock));
 554         return &ei->vfs_inode;
 555 }
 556
 557 static void ext4_destroy_inode(struct inode *inode)
 558 {
 559         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 560                 printk("EXT4 Inode %p: orphan list check failed!\n",
 561                         EXT4_I(inode));
 562                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 563                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 564                                 true);
 565                 dump_stack();
 566         }
 567         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 568 }
 569
 570 static void init_once(void *foo)
 571 {
 572         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 573
 574         INIT_LIST_HEAD(&ei->i_orphan);
 575 #ifdef CONFIG_EXT4_FS_XATTR
 576         init_rwsem(&ei->xattr_sem);
 577 #endif
 578         init_rwsem(&ei->i_data_sem);
 579         inode_init_once(&ei->vfs_inode);
 580 }
 581
 582 static int init_inodecache(void)
 583 {
 584         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 585                                              sizeof(struct ext4_inode_info),
 586                                              0, (SLAB_RECLAIM_ACCOUNT|
 587                                                 SLAB_MEM_SPREAD),
 588                                              init_once);
 589         if (ext4_inode_cachep == NULL)
 590                 return -ENOMEM;
 591         return 0;
 592 }
 593
 594 static void destroy_inodecache(void)
 595 {
 596         kmem_cache_destroy(ext4_inode_cachep);
 597 }
 598
 599 static void ext4_clear_inode(struct inode *inode)
 600 {
 601 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 602         if (EXT4_I(inode)->i_acl &&
 603                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 604                 posix_acl_release(EXT4_I(inode)->i_acl);
 605                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 606         }
 607         if (EXT4_I(inode)->i_default_acl &&
 608                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 609                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 610                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 611         }
 612 #endif
 613         ext4_discard_preallocations(inode);
 614         if (EXT4_JOURNAL(inode))
 615                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 616                                        &EXT4_I(inode)->jinode);
 617 }
 618
 619 static inline void ext4_show_quota_options(struct seq_file *seq,
 620                                            struct super_block *sb)
 621 {
 622 #if defined(CONFIG_QUOTA)
 623         struct ext4_sb_info *sbi = EXT4_SB(sb);
 624
 625         if (sbi->s_jquota_fmt)
 626                 seq_printf(seq, ",jqfmt=%s",
 627                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 628
 629         if (sbi->s_qf_names[USRQUOTA])
 630                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 631
 632         if (sbi->s_qf_names[GRPQUOTA])
 633                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 634
 635         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 636                 seq_puts(seq, ",usrquota");
 637
 638         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 639                 seq_puts(seq, ",grpquota");
 640 #endif
 641 }
 642
 643 /*
 644  * Show an option if
 645  *  - it's set to a non-default value OR
 646  *  - if the per-sb default is different from the global default
 647  */
 648 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 649 {
 650         int def_errors;
 651         unsigned long def_mount_opts;
 652         struct super_block *sb = vfs->mnt_sb;
 653         struct ext4_sb_info *sbi = EXT4_SB(sb);
 654         struct ext4_super_block *es = sbi->s_es;
 655
 656         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 657         def_errors     = le16_to_cpu(es->s_errors);
 658
 659         if (sbi->s_sb_block != 1)
 660                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 661         if (test_opt(sb, MINIX_DF))
 662                 seq_puts(seq, ",minixdf");
 663         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 664                 seq_puts(seq, ",grpid");
 665         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 666                 seq_puts(seq, ",nogrpid");
 667         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 668             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 669                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 670         }
 671         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 672             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 673                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 674         }
 675         if (test_opt(sb, ERRORS_RO)) {
 676                 if (def_errors == EXT4_ERRORS_PANIC ||
 677                     def_errors == EXT4_ERRORS_CONTINUE) {
 678                         seq_puts(seq, ",errors=remount-ro");
 679                 }
 680         }
 681         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 682                 seq_puts(seq, ",errors=continue");
 683         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 684                 seq_puts(seq, ",errors=panic");
 685         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 686                 seq_puts(seq, ",nouid32");
 687         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 688                 seq_puts(seq, ",debug");
 689         if (test_opt(sb, OLDALLOC))
 690                 seq_puts(seq, ",oldalloc");
 691 #ifdef CONFIG_EXT4_FS_XATTR
 692         if (test_opt(sb, XATTR_USER) &&
 693                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 694                 seq_puts(seq, ",user_xattr");
 695         if (!test_opt(sb, XATTR_USER) &&
 696             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 697                 seq_puts(seq, ",nouser_xattr");
 698         }
 699 #endif
 700 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 701         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 702                 seq_puts(seq, ",acl");
 703         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 704                 seq_puts(seq, ",noacl");
 705 #endif
 706         if (!test_opt(sb, RESERVATION))
 707                 seq_puts(seq, ",noreservation");
 708         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 709                 seq_printf(seq, ",commit=%u",
 710                            (unsigned) (sbi->s_commit_interval / HZ));
 711         }
 712         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 713                 seq_printf(seq, ",min_batch_time=%u",
 714                            (unsigned) sbi->s_min_batch_time);
 715         }
 716         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 717                 seq_printf(seq, ",max_batch_time=%u",
 718                            (unsigned) sbi->s_min_batch_time);
 719         }
 720
 721         /*
 722          * We're changing the default of barrier mount option, so
 723          * let's always display its mount state so it's clear what its
 724          * status is.
 725          */
 726         seq_puts(seq, ",barrier=");
 727         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 728         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 729                 seq_puts(seq, ",journal_async_commit");
 730         if (test_opt(sb, NOBH))
 731                 seq_puts(seq, ",nobh");
 732         if (!test_opt(sb, EXTENTS))
 733                 seq_puts(seq, ",noextents");
 734         if (test_opt(sb, I_VERSION))
 735                 seq_puts(seq, ",i_version");
 736         if (!test_opt(sb, DELALLOC))
 737                 seq_puts(seq, ",nodelalloc");
 738
 739
 740         if (sbi->s_stripe)
 741                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 742         /*
 743          * journal mode get enabled in different ways
 744          * So just print the value even if we didn't specify it
 745          */
 746         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 747                 seq_puts(seq, ",data=journal");
 748         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 749                 seq_puts(seq, ",data=ordered");
 750         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 751                 seq_puts(seq, ",data=writeback");
 752
 753         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 754                 seq_printf(seq, ",inode_readahead_blks=%u",
 755                            sbi->s_inode_readahead_blks);
 756
 757         if (test_opt(sb, DATA_ERR_ABORT))
 758                 seq_puts(seq, ",data_err=abort");
 759
 760         ext4_show_quota_options(seq, sb);
 761         return 0;
 762 }
 763
 764
 765 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 766                 u64 ino, u32 generation)
 767 {
 768         struct inode *inode;
 769
 770         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 771                 return ERR_PTR(-ESTALE);
 772         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 773                 return ERR_PTR(-ESTALE);
 774
 775         /* iget isn't really right if the inode is currently unallocated!!
 776          *
 777          * ext4_read_inode will return a bad_inode if the inode had been
 778          * deleted, so we should be safe.
 779          *
 780          * Currently we don't know the generation for parent directory, so
 781          * a generation of 0 means "accept any"
 782          */
 783         inode = ext4_iget(sb, ino);
 784         if (IS_ERR(inode))
 785                 return ERR_CAST(inode);
 786         if (generation && inode->i_generation != generation) {
 787                 iput(inode);
 788                 return ERR_PTR(-ESTALE);
 789         }
 790
 791         return inode;
 792 }
 793
 794 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 795                 int fh_len, int fh_type)
 796 {
 797         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 798                                     ext4_nfs_get_inode);
 799 }
 800
 801 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 802                 int fh_len, int fh_type)
 803 {
 804         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 805                                     ext4_nfs_get_inode);
 806 }
 807
 808 #ifdef CONFIG_QUOTA
 809 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 810 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 811
 812 static int ext4_dquot_initialize(struct inode *inode, int type);
 813 static int ext4_dquot_drop(struct inode *inode);
 814 static int ext4_write_dquot(struct dquot *dquot);
 815 static int ext4_acquire_dquot(struct dquot *dquot);
 816 static int ext4_release_dquot(struct dquot *dquot);
 817 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 818 static int ext4_write_info(struct super_block *sb, int type);
 819 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 820                                 char *path, int remount);
 821 static int ext4_quota_on_mount(struct super_block *sb, int type);
 822 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 823                                size_t len, loff_t off);
 824 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 825                                 const char *data, size_t len, loff_t off);
 826
 827 static struct dquot_operations ext4_quota_operations = {
 828         .initialize     = ext4_dquot_initialize,
 829         .drop           = ext4_dquot_drop,
 830         .alloc_space    = dquot_alloc_space,
 831         .alloc_inode    = dquot_alloc_inode,
 832         .free_space     = dquot_free_space,
 833         .free_inode     = dquot_free_inode,
 834         .transfer       = dquot_transfer,
 835         .write_dquot    = ext4_write_dquot,
 836         .acquire_dquot  = ext4_acquire_dquot,
 837         .release_dquot  = ext4_release_dquot,
 838         .mark_dirty     = ext4_mark_dquot_dirty,
 839         .write_info     = ext4_write_info
 840 };
 841
 842 static struct quotactl_ops ext4_qctl_operations = {
 843         .quota_on       = ext4_quota_on,
 844         .quota_off      = vfs_quota_off,
 845         .quota_sync     = vfs_quota_sync,
 846         .get_info       = vfs_get_dqinfo,
 847         .set_info       = vfs_set_dqinfo,
 848         .get_dqblk      = vfs_get_dqblk,
 849         .set_dqblk      = vfs_set_dqblk
 850 };
 851 #endif
 852
 853 static const struct super_operations ext4_sops = {
 854         .alloc_inode    = ext4_alloc_inode,
 855         .destroy_inode  = ext4_destroy_inode,
 856         .write_inode    = ext4_write_inode,
 857         .dirty_inode    = ext4_dirty_inode,
 858         .delete_inode   = ext4_delete_inode,
 859         .put_super      = ext4_put_super,
 860         .write_super    = ext4_write_super,
 861         .sync_fs        = ext4_sync_fs,
 862         .write_super_lockfs = ext4_write_super_lockfs,
 863         .unlockfs       = ext4_unlockfs,
 864         .statfs         = ext4_statfs,
 865         .remount_fs     = ext4_remount,
 866         .clear_inode    = ext4_clear_inode,
 867         .show_options   = ext4_show_options,
 868 #ifdef CONFIG_QUOTA
 869         .quota_read     = ext4_quota_read,
 870         .quota_write    = ext4_quota_write,
 871 #endif
 872 };
 873
 874 static const struct export_operations ext4_export_ops = {
 875         .fh_to_dentry = ext4_fh_to_dentry,
 876         .fh_to_parent = ext4_fh_to_parent,
 877         .get_parent = ext4_get_parent,
 878 };
 879
 880 enum {
 881         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 882         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 883         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
 884         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 885         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 886         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
 887         Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 888         Opt_journal_checksum, Opt_journal_async_commit,
 889         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 890         Opt_data_err_abort, Opt_data_err_ignore,
 891         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 892         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 893         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 894         Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
 895         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
 896         Opt_inode_readahead_blks
 897 };
 898
 899 static const match_table_t tokens = {
 900         {Opt_bsd_df, "bsddf"},
 901         {Opt_minix_df, "minixdf"},
 902         {Opt_grpid, "grpid"},
 903         {Opt_grpid, "bsdgroups"},
 904         {Opt_nogrpid, "nogrpid"},
 905         {Opt_nogrpid, "sysvgroups"},
 906         {Opt_resgid, "resgid=%u"},
 907         {Opt_resuid, "resuid=%u"},
 908         {Opt_sb, "sb=%u"},
 909         {Opt_err_cont, "errors=continue"},
 910         {Opt_err_panic, "errors=panic"},
 911         {Opt_err_ro, "errors=remount-ro"},
 912         {Opt_nouid32, "nouid32"},
 913         {Opt_debug, "debug"},
 914         {Opt_oldalloc, "oldalloc"},
 915         {Opt_orlov, "orlov"},
 916         {Opt_user_xattr, "user_xattr"},
 917         {Opt_nouser_xattr, "nouser_xattr"},
 918         {Opt_acl, "acl"},
 919         {Opt_noacl, "noacl"},
 920         {Opt_reservation, "reservation"},
 921         {Opt_noreservation, "noreservation"},
 922         {Opt_noload, "noload"},
 923         {Opt_nobh, "nobh"},
 924         {Opt_bh, "bh"},
 925         {Opt_commit, "commit=%u"},
 926         {Opt_min_batch_time, "min_batch_time=%u"},
 927         {Opt_max_batch_time, "max_batch_time=%u"},
 928         {Opt_journal_update, "journal=update"},
 929         {Opt_journal_inum, "journal=%u"},
 930         {Opt_journal_dev, "journal_dev=%u"},
 931         {Opt_journal_checksum, "journal_checksum"},
 932         {Opt_journal_async_commit, "journal_async_commit"},
 933         {Opt_abort, "abort"},
 934         {Opt_data_journal, "data=journal"},
 935         {Opt_data_ordered, "data=ordered"},
 936         {Opt_data_writeback, "data=writeback"},
 937         {Opt_data_err_abort, "data_err=abort"},
 938         {Opt_data_err_ignore, "data_err=ignore"},
 939         {Opt_offusrjquota, "usrjquota="},
 940         {Opt_usrjquota, "usrjquota=%s"},
 941         {Opt_offgrpjquota, "grpjquota="},
 942         {Opt_grpjquota, "grpjquota=%s"},
 943         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 944         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 945         {Opt_grpquota, "grpquota"},
 946         {Opt_noquota, "noquota"},
 947         {Opt_quota, "quota"},
 948         {Opt_usrquota, "usrquota"},
 949         {Opt_barrier, "barrier=%u"},
 950         {Opt_extents, "extents"},
 951         {Opt_noextents, "noextents"},
 952         {Opt_i_version, "i_version"},
 953         {Opt_stripe, "stripe=%u"},
 954         {Opt_resize, "resize"},
 955         {Opt_delalloc, "delalloc"},
 956         {Opt_nodelalloc, "nodelalloc"},
 957         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
 958         {Opt_err, NULL},
 959 };
 960
 961 static ext4_fsblk_t get_sb_block(void **data)
 962 {
 963         ext4_fsblk_t    sb_block;
 964         char            *options = (char *) *data;
 965
 966         if (!options || strncmp(options, "sb=", 3) != 0)
 967                 return 1;       /* Default location */
 968         options += 3;
 969         /*todo: use simple_strtoll with >32bit ext4 */
 970         sb_block = simple_strtoul(options, &options, 0);
 971         if (*options && *options != ',') {
 972                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
 973                        (char *) *data);
 974                 return 1;
 975         }
 976         if (*options == ',')
 977                 options++;
 978         *data = (void *) options;
 979         return sb_block;
 980 }
 981
 982 static int parse_options(char *options, struct super_block *sb,
 983                          unsigned int *inum, unsigned long *journal_devnum,
 984                          ext4_fsblk_t *n_blocks_count, int is_remount)
 985 {
 986         struct ext4_sb_info *sbi = EXT4_SB(sb);
 987         char *p;
 988         substring_t args[MAX_OPT_ARGS];
 989         int data_opt = 0;
 990         int option;
 991 #ifdef CONFIG_QUOTA
 992         int qtype, qfmt;
 993         char *qname;
 994 #endif
 995         ext4_fsblk_t last_block;
 996
 997         if (!options)
 998                 return 1;
 999
1000         while ((p = strsep(&options, ",")) != NULL) {
1001                 int token;
1002                 if (!*p)
1003                         continue;
1004
1005                 token = match_token(p, tokens, args);
1006                 switch (token) {
1007                 case Opt_bsd_df:
1008                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1009                         break;
1010                 case Opt_minix_df:
1011                         set_opt(sbi->s_mount_opt, MINIX_DF);
1012                         break;
1013                 case Opt_grpid:
1014                         set_opt(sbi->s_mount_opt, GRPID);
1015                         break;
1016                 case Opt_nogrpid:
1017                         clear_opt(sbi->s_mount_opt, GRPID);
1018                         break;
1019                 case Opt_resuid:
1020                         if (match_int(&args[0], &option))
1021                                 return 0;
1022                         sbi->s_resuid = option;
1023                         break;
1024                 case Opt_resgid:
1025                         if (match_int(&args[0], &option))
1026                                 return 0;
1027                         sbi->s_resgid = option;
1028                         break;
1029                 case Opt_sb:
1030                         /* handled by get_sb_block() instead of here */
1031                         /* *sb_block = match_int(&args[0]); */
1032                         break;
1033                 case Opt_err_panic:
1034                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1035                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1036                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1037                         break;
1038                 case Opt_err_ro:
1039                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1040                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1041                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1042                         break;
1043                 case Opt_err_cont:
1044                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1045                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1046                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1047                         break;
1048                 case Opt_nouid32:
1049                         set_opt(sbi->s_mount_opt, NO_UID32);
1050                         break;
1051                 case Opt_debug:
1052                         set_opt(sbi->s_mount_opt, DEBUG);
1053                         break;
1054                 case Opt_oldalloc:
1055                         set_opt(sbi->s_mount_opt, OLDALLOC);
1056                         break;
1057                 case Opt_orlov:
1058                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1059                         break;
1060 #ifdef CONFIG_EXT4_FS_XATTR
1061                 case Opt_user_xattr:
1062                         set_opt(sbi->s_mount_opt, XATTR_USER);
1063                         break;
1064                 case Opt_nouser_xattr:
1065                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1066                         break;
1067 #else
1068                 case Opt_user_xattr:
1069                 case Opt_nouser_xattr:
1070                         printk(KERN_ERR "EXT4 (no)user_xattr options "
1071                                "not supported\n");
1072                         break;
1073 #endif
1074 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1075                 case Opt_acl:
1076                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1077                         break;
1078                 case Opt_noacl:
1079                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1080                         break;
1081 #else
1082                 case Opt_acl:
1083                 case Opt_noacl:
1084                         printk(KERN_ERR "EXT4 (no)acl options "
1085                                "not supported\n");
1086                         break;
1087 #endif
1088                 case Opt_reservation:
1089                         set_opt(sbi->s_mount_opt, RESERVATION);
1090                         break;
1091                 case Opt_noreservation:
1092                         clear_opt(sbi->s_mount_opt, RESERVATION);
1093                         break;
1094                 case Opt_journal_update:
1095                         /* @@@ FIXME */
1096                         /* Eventually we will want to be able to create
1097                            a journal file here.  For now, only allow the
1098                            user to specify an existing inode to be the
1099                            journal file. */
1100                         if (is_remount) {
1101                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1102                                        "journal on remount\n");
1103                                 return 0;
1104                         }
1105                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1106                         break;
1107                 case Opt_journal_inum:
1108                         if (is_remount) {
1109                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1110                                        "journal on remount\n");
1111                                 return 0;
1112                         }
1113                         if (match_int(&args[0], &option))
1114                                 return 0;
1115                         *inum = option;
1116                         break;
1117                 case Opt_journal_dev:
1118                         if (is_remount) {
1119                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1120                                        "journal on remount\n");
1121                                 return 0;
1122                         }
1123                         if (match_int(&args[0], &option))
1124                                 return 0;
1125                         *journal_devnum = option;
1126                         break;
1127                 case Opt_journal_checksum:
1128                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1129                         break;
1130                 case Opt_journal_async_commit:
1131                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1132                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1133                         break;
1134                 case Opt_noload:
1135                         set_opt(sbi->s_mount_opt, NOLOAD);
1136                         break;
1137                 case Opt_commit:
1138                         if (match_int(&args[0], &option))
1139                                 return 0;
1140                         if (option < 0)
1141                                 return 0;
1142                         if (option == 0)
1143                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1144                         sbi->s_commit_interval = HZ * option;
1145                         break;
1146                 case Opt_max_batch_time:
1147                         if (match_int(&args[0], &option))
1148                                 return 0;
1149                         if (option < 0)
1150                                 return 0;
1151                         if (option == 0)
1152                                 option = EXT4_DEF_MAX_BATCH_TIME;
1153                         sbi->s_max_batch_time = option;
1154                         break;
1155                 case Opt_min_batch_time:
1156                         if (match_int(&args[0], &option))
1157                                 return 0;
1158                         if (option < 0)
1159                                 return 0;
1160                         sbi->s_min_batch_time = option;
1161                         break;
1162                 case Opt_data_journal:
1163                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1164                         goto datacheck;
1165                 case Opt_data_ordered:
1166                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1167                         goto datacheck;
1168                 case Opt_data_writeback:
1169                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1170                 datacheck:
1171                         if (is_remount) {
1172                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1173                                                 != data_opt) {
1174                                         printk(KERN_ERR
1175                                                 "EXT4-fs: cannot change data "
1176                                                 "mode on remount\n");
1177                                         return 0;
1178                                 }
1179                         } else {
1180                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1181                                 sbi->s_mount_opt |= data_opt;
1182                         }
1183                         break;
1184                 case Opt_data_err_abort:
1185                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1186                         break;
1187                 case Opt_data_err_ignore:
1188                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1189                         break;
1190 #ifdef CONFIG_QUOTA
1191                 case Opt_usrjquota:
1192                         qtype = USRQUOTA;
1193                         goto set_qf_name;
1194                 case Opt_grpjquota:
1195                         qtype = GRPQUOTA;
1196 set_qf_name:
1197                         if ((sb_any_quota_enabled(sb) ||
1198                              sb_any_quota_suspended(sb)) &&
1199                             !sbi->s_qf_names[qtype]) {
1200                                 printk(KERN_ERR
1201                                        "EXT4-fs: Cannot change journaled "
1202                                        "quota options when quota turned on.\n");
1203                                 return 0;
1204                         }
1205                         qname = match_strdup(&args[0]);
1206                         if (!qname) {
1207                                 printk(KERN_ERR
1208                                         "EXT4-fs: not enough memory for "
1209                                         "storing quotafile name.\n");
1210                                 return 0;
1211                         }
1212                         if (sbi->s_qf_names[qtype] &&
1213                             strcmp(sbi->s_qf_names[qtype], qname)) {
1214                                 printk(KERN_ERR
1215                                         "EXT4-fs: %s quota file already "
1216                                         "specified.\n", QTYPE2NAME(qtype));
1217                                 kfree(qname);
1218                                 return 0;
1219                         }
1220                         sbi->s_qf_names[qtype] = qname;
1221                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1222                                 printk(KERN_ERR
1223                                         "EXT4-fs: quotafile must be on "
1224                                         "filesystem root.\n");
1225                                 kfree(sbi->s_qf_names[qtype]);
1226                                 sbi->s_qf_names[qtype] = NULL;
1227                                 return 0;
1228                         }
1229                         set_opt(sbi->s_mount_opt, QUOTA);
1230                         break;
1231                 case Opt_offusrjquota:
1232                         qtype = USRQUOTA;
1233                         goto clear_qf_name;
1234                 case Opt_offgrpjquota:
1235                         qtype = GRPQUOTA;
1236 clear_qf_name:
1237                         if ((sb_any_quota_enabled(sb) ||
1238                              sb_any_quota_suspended(sb)) &&
1239                             sbi->s_qf_names[qtype]) {
1240                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1241                                         "journaled quota options when "
1242                                         "quota turned on.\n");
1243                                 return 0;
1244                         }
1245                         /*
1246                          * The space will be released later when all options
1247                          * are confirmed to be correct
1248                          */
1249                         sbi->s_qf_names[qtype] = NULL;
1250                         break;
1251                 case Opt_jqfmt_vfsold:
1252                         qfmt = QFMT_VFS_OLD;
1253                         goto set_qf_format;
1254                 case Opt_jqfmt_vfsv0:
1255                         qfmt = QFMT_VFS_V0;
1256 set_qf_format:
1257                         if ((sb_any_quota_enabled(sb) ||
1258                              sb_any_quota_suspended(sb)) &&
1259                             sbi->s_jquota_fmt != qfmt) {
1260                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1261                                         "journaled quota options when "
1262                                         "quota turned on.\n");
1263                                 return 0;
1264                         }
1265                         sbi->s_jquota_fmt = qfmt;
1266                         break;
1267                 case Opt_quota:
1268                 case Opt_usrquota:
1269                         set_opt(sbi->s_mount_opt, QUOTA);
1270                         set_opt(sbi->s_mount_opt, USRQUOTA);
1271                         break;
1272                 case Opt_grpquota:
1273                         set_opt(sbi->s_mount_opt, QUOTA);
1274                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1275                         break;
1276                 case Opt_noquota:
1277                         if (sb_any_quota_enabled(sb)) {
1278                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1279                                         "options when quota turned on.\n");
1280                                 return 0;
1281                         }
1282                         clear_opt(sbi->s_mount_opt, QUOTA);
1283                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1284                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1285                         break;
1286 #else
1287                 case Opt_quota:
1288                 case Opt_usrquota:
1289                 case Opt_grpquota:
1290                         printk(KERN_ERR
1291                                 "EXT4-fs: quota options not supported.\n");
1292                         break;
1293                 case Opt_usrjquota:
1294                 case Opt_grpjquota:
1295                 case Opt_offusrjquota:
1296                 case Opt_offgrpjquota:
1297                 case Opt_jqfmt_vfsold:
1298                 case Opt_jqfmt_vfsv0:
1299                         printk(KERN_ERR
1300                                 "EXT4-fs: journaled quota options not "
1301                                 "supported.\n");
1302                         break;
1303                 case Opt_noquota:
1304                         break;
1305 #endif
1306                 case Opt_abort:
1307                         set_opt(sbi->s_mount_opt, ABORT);
1308                         break;
1309                 case Opt_barrier:
1310                         if (match_int(&args[0], &option))
1311                                 return 0;
1312                         if (option)
1313                                 set_opt(sbi->s_mount_opt, BARRIER);
1314                         else
1315                                 clear_opt(sbi->s_mount_opt, BARRIER);
1316                         break;
1317                 case Opt_ignore:
1318                         break;
1319                 case Opt_resize:
1320                         if (!is_remount) {
1321                                 printk("EXT4-fs: resize option only available "
1322                                         "for remount\n");
1323                                 return 0;
1324                         }
1325                         if (match_int(&args[0], &option) != 0)
1326                                 return 0;
1327                         *n_blocks_count = option;
1328                         break;
1329                 case Opt_nobh:
1330                         set_opt(sbi->s_mount_opt, NOBH);
1331                         break;
1332                 case Opt_bh:
1333                         clear_opt(sbi->s_mount_opt, NOBH);
1334                         break;
1335                 case Opt_extents:
1336                         if (!EXT4_HAS_INCOMPAT_FEATURE(sb,
1337                                         EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1338                                 ext4_warning(sb, __func__,
1339                                         "extents feature not enabled "
1340                                         "on this filesystem, use tune2fs");
1341                                 return 0;
1342                         }
1343                         set_opt(sbi->s_mount_opt, EXTENTS);
1344                         break;
1345                 case Opt_noextents:
1346                         /*
1347                          * When e2fsprogs support resizing an already existing
1348                          * ext3 file system to greater than 2**32 we need to
1349                          * add support to block allocator to handle growing
1350                          * already existing block  mapped inode so that blocks
1351                          * allocated for them fall within 2**32
1352                          */
1353                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1354                         if (last_block  > 0xffffffffULL) {
1355                                 printk(KERN_ERR "EXT4-fs: Filesystem too "
1356                                                 "large to mount with "
1357                                                 "-o noextents options\n");
1358                                 return 0;
1359                         }
1360                         clear_opt(sbi->s_mount_opt, EXTENTS);
1361                         break;
1362                 case Opt_i_version:
1363                         set_opt(sbi->s_mount_opt, I_VERSION);
1364                         sb->s_flags |= MS_I_VERSION;
1365                         break;
1366                 case Opt_nodelalloc:
1367                         clear_opt(sbi->s_mount_opt, DELALLOC);
1368                         break;
1369                 case Opt_stripe:
1370                         if (match_int(&args[0], &option))
1371                                 return 0;
1372                         if (option < 0)
1373                                 return 0;
1374                         sbi->s_stripe = option;
1375                         break;
1376                 case Opt_delalloc:
1377                         set_opt(sbi->s_mount_opt, DELALLOC);
1378                         break;
1379                 case Opt_inode_readahead_blks:
1380                         if (match_int(&args[0], &option))
1381                                 return 0;
1382                         if (option < 0 || option > (1 << 30))
1383                                 return 0;
1384                         sbi->s_inode_readahead_blks = option;
1385                         break;
1386                 default:
1387                         printk(KERN_ERR
1388                                "EXT4-fs: Unrecognized mount option \"%s\" "
1389                                "or missing value\n", p);
1390                         return 0;
1391                 }
1392         }
1393 #ifdef CONFIG_QUOTA
1394         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1395                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1396                      sbi->s_qf_names[USRQUOTA])
1397                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1398
1399                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1400                      sbi->s_qf_names[GRPQUOTA])
1401                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1402
1403                 if ((sbi->s_qf_names[USRQUOTA] &&
1404                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1405                     (sbi->s_qf_names[GRPQUOTA] &&
1406                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1407                         printk(KERN_ERR "EXT4-fs: old and new quota "
1408                                         "format mixing.\n");
1409                         return 0;
1410                 }
1411
1412                 if (!sbi->s_jquota_fmt) {
1413                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1414                                         "not specified.\n");
1415                         return 0;
1416                 }
1417         } else {
1418                 if (sbi->s_jquota_fmt) {
1419                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1420                                         "specified with no journaling "
1421                                         "enabled.\n");
1422                         return 0;
1423                 }
1424         }
1425 #endif
1426         return 1;
1427 }
1428
1429 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1430                             int read_only)
1431 {
1432         struct ext4_sb_info *sbi = EXT4_SB(sb);
1433         int res = 0;
1434
1435         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1436                 printk(KERN_ERR "EXT4-fs warning: revision level too high, "
1437                        "forcing read-only mode\n");
1438                 res = MS_RDONLY;
1439         }
1440         if (read_only)
1441                 return res;
1442         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1443                 printk(KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1444                        "running e2fsck is recommended\n");
1445         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1446                 printk(KERN_WARNING
1447                        "EXT4-fs warning: mounting fs with errors, "
1448                        "running e2fsck is recommended\n");
1449         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1450                  le16_to_cpu(es->s_mnt_count) >=
1451                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1452                 printk(KERN_WARNING
1453                        "EXT4-fs warning: maximal mount count reached, "
1454                        "running e2fsck is recommended\n");
1455         else if (le32_to_cpu(es->s_checkinterval) &&
1456                 (le32_to_cpu(es->s_lastcheck) +
1457                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1458                 printk(KERN_WARNING
1459                        "EXT4-fs warning: checktime reached, "
1460                        "running e2fsck is recommended\n");
1461         if (!sbi->s_journal)
1462                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1463         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1464                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1465         le16_add_cpu(&es->s_mnt_count, 1);
1466         es->s_mtime = cpu_to_le32(get_seconds());
1467         ext4_update_dynamic_rev(sb);
1468         if (sbi->s_journal)
1469                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1470
1471         ext4_commit_super(sb, es, 1);
1472         if (test_opt(sb, DEBUG))
1473                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1474                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1475                         sb->s_blocksize,
1476                         sbi->s_groups_count,
1477                         EXT4_BLOCKS_PER_GROUP(sb),
1478                         EXT4_INODES_PER_GROUP(sb),
1479                         sbi->s_mount_opt);
1480
1481         if (EXT4_SB(sb)->s_journal) {
1482                 printk(KERN_INFO "EXT4 FS on %s, %s journal on %s\n",
1483                        sb->s_id, EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1484                        "external", EXT4_SB(sb)->s_journal->j_devname);
1485         } else {
1486                 printk(KERN_INFO "EXT4 FS on %s, no journal\n", sb->s_id);
1487         }
1488         return res;
1489 }
1490
1491 static int ext4_fill_flex_info(struct super_block *sb)
1492 {
1493         struct ext4_sb_info *sbi = EXT4_SB(sb);
1494         struct ext4_group_desc *gdp = NULL;
1495         struct buffer_head *bh;
1496         ext4_group_t flex_group_count;
1497         ext4_group_t flex_group;
1498         int groups_per_flex = 0;
1499         int i;
1500
1501         if (!sbi->s_es->s_log_groups_per_flex) {
1502                 sbi->s_log_groups_per_flex = 0;
1503                 return 1;
1504         }
1505
1506         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1507         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1508
1509         /* We allocate both existing and potentially added groups */
1510         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1511                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1512                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1513         sbi->s_flex_groups = kzalloc(flex_group_count *
1514                                      sizeof(struct flex_groups), GFP_KERNEL);
1515         if (sbi->s_flex_groups == NULL) {
1516                 printk(KERN_ERR "EXT4-fs: not enough memory for "
1517                                 "%lu flex groups\n", flex_group_count);
1518                 goto failed;
1519         }
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                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1602                                "Block bitmap for group %lu not in group "
1603                                "(block %llu)!\n", i, block_bitmap);
1604                         return 0;
1605                 }
1606                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1607                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1608                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1609                                "Inode bitmap for group %lu not in group "
1610                                "(block %llu)!\n", i, inode_bitmap);
1611                         return 0;
1612                 }
1613                 inode_table = ext4_inode_table(sb, gdp);
1614                 if (inode_table < first_block ||
1615                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1616                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1617                                "Inode table for group %lu not in group "
1618                                "(block %llu)!\n", i, inode_table);
1619                         return 0;
1620                 }
1621                 spin_lock(sb_bgl_lock(sbi, i));
1622                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1623                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1624                                "Checksum for group %lu failed (%u!=%u)\n",
1625                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1626                                gdp)), le16_to_cpu(gdp->bg_checksum));
1627                         if (!(sb->s_flags & MS_RDONLY)) {
1628                                 spin_unlock(sb_bgl_lock(sbi, i));
1629                                 return 0;
1630                         }
1631                 }
1632                 spin_unlock(sb_bgl_lock(sbi, i));
1633                 if (!flexbg_flag)
1634                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1635         }
1636
1637         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1638         sbi->s_es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
1639         return 1;
1640 }
1641
1642 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1643  * the superblock) which were deleted from all directories, but held open by
1644  * a process at the time of a crash.  We walk the list and try to delete these
1645  * inodes at recovery time (only with a read-write filesystem).
1646  *
1647  * In order to keep the orphan inode chain consistent during traversal (in
1648  * case of crash during recovery), we link each inode into the superblock
1649  * orphan list_head and handle it the same way as an inode deletion during
1650  * normal operation (which journals the operations for us).
1651  *
1652  * We only do an iget() and an iput() on each inode, which is very safe if we
1653  * accidentally point at an in-use or already deleted inode.  The worst that
1654  * can happen in this case is that we get a "bit already cleared" message from
1655  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1656  * e2fsck was run on this filesystem, and it must have already done the orphan
1657  * inode cleanup for us, so we can safely abort without any further action.
1658  */
1659 static void ext4_orphan_cleanup(struct super_block *sb,
1660                                 struct ext4_super_block *es)
1661 {
1662         unsigned int s_flags = sb->s_flags;
1663         int nr_orphans = 0, nr_truncates = 0;
1664 #ifdef CONFIG_QUOTA
1665         int i;
1666 #endif
1667         if (!es->s_last_orphan) {
1668                 jbd_debug(4, "no orphan inodes to clean up\n");
1669                 return;
1670         }
1671
1672         if (bdev_read_only(sb->s_bdev)) {
1673                 printk(KERN_ERR "EXT4-fs: write access "
1674                         "unavailable, skipping orphan cleanup.\n");
1675                 return;
1676         }
1677
1678         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1679                 if (es->s_last_orphan)
1680                         jbd_debug(1, "Errors on filesystem, "
1681                                   "clearing orphan list.\n");
1682                 es->s_last_orphan = 0;
1683                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1684                 return;
1685         }
1686
1687         if (s_flags & MS_RDONLY) {
1688                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1689                        sb->s_id);
1690                 sb->s_flags &= ~MS_RDONLY;
1691         }
1692 #ifdef CONFIG_QUOTA
1693         /* Needed for iput() to work correctly and not trash data */
1694         sb->s_flags |= MS_ACTIVE;
1695         /* Turn on quotas so that they are updated correctly */
1696         for (i = 0; i < MAXQUOTAS; i++) {
1697                 if (EXT4_SB(sb)->s_qf_names[i]) {
1698                         int ret = ext4_quota_on_mount(sb, i);
1699                         if (ret < 0)
1700                                 printk(KERN_ERR
1701                                         "EXT4-fs: Cannot turn on journaled "
1702                                         "quota: error %d\n", ret);
1703                 }
1704         }
1705 #endif
1706
1707         while (es->s_last_orphan) {
1708                 struct inode *inode;
1709
1710                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1711                 if (IS_ERR(inode)) {
1712                         es->s_last_orphan = 0;
1713                         break;
1714                 }
1715
1716                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1717                 DQUOT_INIT(inode);
1718                 if (inode->i_nlink) {
1719                         printk(KERN_DEBUG
1720                                 "%s: truncating inode %lu to %lld bytes\n",
1721                                 __func__, inode->i_ino, inode->i_size);
1722                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1723                                   inode->i_ino, inode->i_size);
1724                         ext4_truncate(inode);
1725                         nr_truncates++;
1726                 } else {
1727                         printk(KERN_DEBUG
1728                                 "%s: deleting unreferenced inode %lu\n",
1729                                 __func__, inode->i_ino);
1730                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1731                                   inode->i_ino);
1732                         nr_orphans++;
1733                 }
1734                 iput(inode);  /* The delete magic happens here! */
1735         }
1736
1737 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1738
1739         if (nr_orphans)
1740                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1741                        sb->s_id, PLURAL(nr_orphans));
1742         if (nr_truncates)
1743                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1744                        sb->s_id, PLURAL(nr_truncates));
1745 #ifdef CONFIG_QUOTA
1746         /* Turn quotas off */
1747         for (i = 0; i < MAXQUOTAS; i++) {
1748                 if (sb_dqopt(sb)->files[i])
1749                         vfs_quota_off(sb, i, 0);
1750         }
1751 #endif
1752         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1753 }
1754 /*
1755  * Maximal extent format file size.
1756  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1757  * extent format containers, within a sector_t, and within i_blocks
1758  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1759  * so that won't be a limiting factor.
1760  *
1761  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1762  */
1763 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1764 {
1765         loff_t res;
1766         loff_t upper_limit = MAX_LFS_FILESIZE;
1767
1768         /* small i_blocks in vfs inode? */
1769         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1770                 /*
1771                  * CONFIG_LBD is not enabled implies the inode
1772                  * i_block represent total blocks in 512 bytes
1773                  * 32 == size of vfs inode i_blocks * 8
1774                  */
1775                 upper_limit = (1LL << 32) - 1;
1776
1777                 /* total blocks in file system block size */
1778                 upper_limit >>= (blkbits - 9);
1779                 upper_limit <<= blkbits;
1780         }
1781
1782         /* 32-bit extent-start container, ee_block */
1783         res = 1LL << 32;
1784         res <<= blkbits;
1785         res -= 1;
1786
1787         /* Sanity check against vm- & vfs- imposed limits */
1788         if (res > upper_limit)
1789                 res = upper_limit;
1790
1791         return res;
1792 }
1793
1794 /*
1795  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1796  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1797  * We need to be 1 filesystem block less than the 2^48 sector limit.
1798  */
1799 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
1800 {
1801         loff_t res = EXT4_NDIR_BLOCKS;
1802         int meta_blocks;
1803         loff_t upper_limit;
1804         /* This is calculated to be the largest file size for a
1805          * dense, bitmapped file such that the total number of
1806          * sectors in the file, including data and all indirect blocks,
1807          * does not exceed 2^48 -1
1808          * __u32 i_blocks_lo and _u16 i_blocks_high representing the
1809          * total number of  512 bytes blocks of the file
1810          */
1811
1812         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1813                 /*
1814                  * !has_huge_files or CONFIG_LBD is not enabled
1815                  * implies the inode i_block represent total blocks in
1816                  * 512 bytes 32 == size of vfs inode i_blocks * 8
1817                  */
1818                 upper_limit = (1LL << 32) - 1;
1819
1820                 /* total blocks in file system block size */
1821                 upper_limit >>= (bits - 9);
1822
1823         } else {
1824                 /*
1825                  * We use 48 bit ext4_inode i_blocks
1826                  * With EXT4_HUGE_FILE_FL set the i_blocks
1827                  * represent total number of blocks in
1828                  * file system block size
1829                  */
1830                 upper_limit = (1LL << 48) - 1;
1831
1832         }
1833
1834         /* indirect blocks */
1835         meta_blocks = 1;
1836         /* double indirect blocks */
1837         meta_blocks += 1 + (1LL << (bits-2));
1838         /* tripple indirect blocks */
1839         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
1840
1841         upper_limit -= meta_blocks;
1842         upper_limit <<= bits;
1843
1844         res += 1LL << (bits-2);
1845         res += 1LL << (2*(bits-2));
1846         res += 1LL << (3*(bits-2));
1847         res <<= bits;
1848         if (res > upper_limit)
1849                 res = upper_limit;
1850
1851         if (res > MAX_LFS_FILESIZE)
1852                 res = MAX_LFS_FILESIZE;
1853
1854         return res;
1855 }
1856
1857 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1858                                 ext4_fsblk_t logical_sb_block, int nr)
1859 {
1860         struct ext4_sb_info *sbi = EXT4_SB(sb);
1861         ext4_group_t bg, first_meta_bg;
1862         int has_super = 0;
1863
1864         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1865
1866         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1867             nr < first_meta_bg)
1868                 return logical_sb_block + nr + 1;
1869         bg = sbi->s_desc_per_block * nr;
1870         if (ext4_bg_has_super(sb, bg))
1871                 has_super = 1;
1872         return (has_super + ext4_group_first_block_no(sb, bg));
1873 }
1874
1875 /**
1876  * ext4_get_stripe_size: Get the stripe size.
1877  * @sbi: In memory super block info
1878  *
1879  * If we have specified it via mount option, then
1880  * use the mount option value. If the value specified at mount time is
1881  * greater than the blocks per group use the super block value.
1882  * If the super block value is greater than blocks per group return 0.
1883  * Allocator needs it be less than blocks per group.
1884  *
1885  */
1886 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
1887 {
1888         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
1889         unsigned long stripe_width =
1890                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
1891
1892         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
1893                 return sbi->s_stripe;
1894
1895         if (stripe_width <= sbi->s_blocks_per_group)
1896                 return stripe_width;
1897
1898         if (stride <= sbi->s_blocks_per_group)
1899                 return stride;
1900
1901         return 0;
1902 }
1903
1904 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
1905                                 __releases(kernel_lock)
1906                                 __acquires(kernel_lock)
1907
1908 {
1909         struct buffer_head *bh;
1910         struct ext4_super_block *es = NULL;
1911         struct ext4_sb_info *sbi;
1912         ext4_fsblk_t block;
1913         ext4_fsblk_t sb_block = get_sb_block(&data);
1914         ext4_fsblk_t logical_sb_block;
1915         unsigned long offset = 0;
1916         unsigned int journal_inum = 0;
1917         unsigned long journal_devnum = 0;
1918         unsigned long def_mount_opts;
1919         struct inode *root;
1920         char *cp;
1921         const char *descr;
1922         int ret = -EINVAL;
1923         int blocksize;
1924         int db_count;
1925         int i;
1926         int needs_recovery, has_huge_files;
1927         __le32 features;
1928         __u64 blocks_count;
1929         int err;
1930
1931         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1932         if (!sbi)
1933                 return -ENOMEM;
1934         sb->s_fs_info = sbi;
1935         sbi->s_mount_opt = 0;
1936         sbi->s_resuid = EXT4_DEF_RESUID;
1937         sbi->s_resgid = EXT4_DEF_RESGID;
1938         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
1939         sbi->s_sb_block = sb_block;
1940
1941         unlock_kernel();
1942
1943         /* Cleanup superblock name */
1944         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
1945                 *cp = '!';
1946
1947         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1948         if (!blocksize) {
1949                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1950                 goto out_fail;
1951         }
1952
1953         /*
1954          * The ext4 superblock will not be buffer aligned for other than 1kB
1955          * block sizes.  We need to calculate the offset from buffer start.
1956          */
1957         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1958                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1959                 offset = do_div(logical_sb_block, blocksize);
1960         } else {
1961                 logical_sb_block = sb_block;
1962         }
1963
1964         if (!(bh = sb_bread(sb, logical_sb_block))) {
1965                 printk(KERN_ERR "EXT4-fs: unable to read superblock\n");
1966                 goto out_fail;
1967         }
1968         /*
1969          * Note: s_es must be initialized as soon as possible because
1970          *       some ext4 macro-instructions depend on its value
1971          */
1972         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1973         sbi->s_es = es;
1974         sb->s_magic = le16_to_cpu(es->s_magic);
1975         if (sb->s_magic != EXT4_SUPER_MAGIC)
1976                 goto cantfind_ext4;
1977
1978         /* Set defaults before we parse the mount options */
1979         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1980         if (def_mount_opts & EXT4_DEFM_DEBUG)
1981                 set_opt(sbi->s_mount_opt, DEBUG);
1982         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1983                 set_opt(sbi->s_mount_opt, GRPID);
1984         if (def_mount_opts & EXT4_DEFM_UID16)
1985                 set_opt(sbi->s_mount_opt, NO_UID32);
1986 #ifdef CONFIG_EXT4_FS_XATTR
1987         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1988                 set_opt(sbi->s_mount_opt, XATTR_USER);
1989 #endif
1990 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1991         if (def_mount_opts & EXT4_DEFM_ACL)
1992                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1993 #endif
1994         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1995                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1996         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1997                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1998         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1999                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2000
2001         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2002                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2003         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2004                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2005         else
2006                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2007
2008         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2009         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2010         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2011         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2012         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2013
2014         set_opt(sbi->s_mount_opt, RESERVATION);
2015         set_opt(sbi->s_mount_opt, BARRIER);
2016
2017         /*
2018          * turn on extents feature by default in ext4 filesystem
2019          * only if feature flag already set by mkfs or tune2fs.
2020          * Use -o noextents to turn it off
2021          */
2022         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2023                 set_opt(sbi->s_mount_opt, EXTENTS);
2024         else
2025                 ext4_warning(sb, __func__,
2026                         "extents feature not enabled on this filesystem, "
2027                         "use tune2fs.");
2028
2029         /*
2030          * enable delayed allocation by default
2031          * Use -o nodelalloc to turn it off
2032          */
2033         set_opt(sbi->s_mount_opt, DELALLOC);
2034
2035
2036         if (!parse_options((char *) data, sb, &journal_inum, &journal_devnum,
2037                            NULL, 0))
2038                 goto failed_mount;
2039
2040         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2041                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2042
2043         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2044             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2045              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2046              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2047                 printk(KERN_WARNING
2048                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2049                        "running e2fsck is recommended\n");
2050
2051         /*
2052          * Check feature flags regardless of the revision level, since we
2053          * previously didn't change the revision level when setting the flags,
2054          * so there is a chance incompat flags are set on a rev 0 filesystem.
2055          */
2056         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2057         if (features) {
2058                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2059                        "unsupported optional features (%x).\n",
2060                        sb->s_id, le32_to_cpu(features));
2061                 goto failed_mount;
2062         }
2063         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2064         if (!(sb->s_flags & MS_RDONLY) && features) {
2065                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2066                        "unsupported optional features (%x).\n",
2067                        sb->s_id, le32_to_cpu(features));
2068                 goto failed_mount;
2069         }
2070         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2071                                     EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2072         if (has_huge_files) {
2073                 /*
2074                  * Large file size enabled file system can only be
2075                  * mount if kernel is build with CONFIG_LBD
2076                  */
2077                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2078                                 !(sb->s_flags & MS_RDONLY)) {
2079                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2080                                         "files cannot be mounted read-write "
2081                                         "without CONFIG_LBD.\n", sb->s_id);
2082                         goto failed_mount;
2083                 }
2084         }
2085         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2086
2087         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2088             blocksize > EXT4_MAX_BLOCK_SIZE) {
2089                 printk(KERN_ERR
2090                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2091                        blocksize, sb->s_id);
2092                 goto failed_mount;
2093         }
2094
2095         if (sb->s_blocksize != blocksize) {
2096
2097                 /* Validate the filesystem blocksize */
2098                 if (!sb_set_blocksize(sb, blocksize)) {
2099                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2100                                         blocksize);
2101                         goto failed_mount;
2102                 }
2103
2104                 brelse(bh);
2105                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2106                 offset = do_div(logical_sb_block, blocksize);
2107                 bh = sb_bread(sb, logical_sb_block);
2108                 if (!bh) {
2109                         printk(KERN_ERR
2110                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2111                         goto failed_mount;
2112                 }
2113                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2114                 sbi->s_es = es;
2115                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2116                         printk(KERN_ERR
2117                                "EXT4-fs: Magic mismatch, very weird !\n");
2118                         goto failed_mount;
2119                 }
2120         }
2121
2122         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2123                                                       has_huge_files);
2124         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2125
2126         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2127                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2128                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2129         } else {
2130                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2131                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2132                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2133                     (!is_power_of_2(sbi->s_inode_size)) ||
2134                     (sbi->s_inode_size > blocksize)) {
2135                         printk(KERN_ERR
2136                                "EXT4-fs: unsupported inode size: %d\n",
2137                                sbi->s_inode_size);
2138                         goto failed_mount;
2139                 }
2140                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2141                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2142         }
2143         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2144         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2145                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2146                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2147                     !is_power_of_2(sbi->s_desc_size)) {
2148                         printk(KERN_ERR
2149                                "EXT4-fs: unsupported descriptor size %lu\n",
2150                                sbi->s_desc_size);
2151                         goto failed_mount;
2152                 }
2153         } else
2154                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2155         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2156         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2157         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2158                 goto cantfind_ext4;
2159         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2160         if (sbi->s_inodes_per_block == 0)
2161                 goto cantfind_ext4;
2162         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2163                                         sbi->s_inodes_per_block;
2164         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2165         sbi->s_sbh = bh;
2166         sbi->s_mount_state = le16_to_cpu(es->s_state);
2167         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2168         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2169         for (i = 0; i < 4; i++)
2170                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2171         sbi->s_def_hash_version = es->s_def_hash_version;
2172         i = le32_to_cpu(es->s_flags);
2173         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2174                 sbi->s_hash_unsigned = 3;
2175         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2176 #ifdef __CHAR_UNSIGNED__
2177                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2178                 sbi->s_hash_unsigned = 3;
2179 #else
2180                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2181 #endif
2182                 sb->s_dirt = 1;
2183         }
2184
2185         if (sbi->s_blocks_per_group > blocksize * 8) {
2186                 printk(KERN_ERR
2187                        "EXT4-fs: #blocks per group too big: %lu\n",
2188                        sbi->s_blocks_per_group);
2189                 goto failed_mount;
2190         }
2191         if (sbi->s_inodes_per_group > blocksize * 8) {
2192                 printk(KERN_ERR
2193                        "EXT4-fs: #inodes per group too big: %lu\n",
2194                        sbi->s_inodes_per_group);
2195                 goto failed_mount;
2196         }
2197
2198         if (ext4_blocks_count(es) >
2199                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2200                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2201                         " too large to mount safely\n", sb->s_id);
2202                 if (sizeof(sector_t) < 8)
2203                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2204                                         "enabled\n");
2205                 goto failed_mount;
2206         }
2207
2208         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2209                 goto cantfind_ext4;
2210
2211         /* ensure blocks_count calculation below doesn't sign-extend */
2212         if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
2213             le32_to_cpu(es->s_first_data_block) + 1) {
2214                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
2215                        "first data block %u, blocks per group %lu\n",
2216                         ext4_blocks_count(es),
2217                         le32_to_cpu(es->s_first_data_block),
2218                         EXT4_BLOCKS_PER_GROUP(sb));
2219                 goto failed_mount;
2220         }
2221         blocks_count = (ext4_blocks_count(es) -
2222                         le32_to_cpu(es->s_first_data_block) +
2223                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2224         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2225         sbi->s_groups_count = blocks_count;
2226         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2227                    EXT4_DESC_PER_BLOCK(sb);
2228         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2229                                     GFP_KERNEL);
2230         if (sbi->s_group_desc == NULL) {
2231                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
2232                 goto failed_mount;
2233         }
2234
2235 #ifdef CONFIG_PROC_FS
2236         if (ext4_proc_root)
2237                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2238
2239         if (sbi->s_proc)
2240                 proc_create_data("inode_readahead_blks", 0644, sbi->s_proc,
2241                                  &ext4_ui_proc_fops,
2242                                  &sbi->s_inode_readahead_blks);
2243 #endif
2244
2245         bgl_lock_init(&sbi->s_blockgroup_lock);
2246
2247         for (i = 0; i < db_count; i++) {
2248                 block = descriptor_loc(sb, logical_sb_block, i);
2249                 sbi->s_group_desc[i] = sb_bread(sb, block);
2250                 if (!sbi->s_group_desc[i]) {
2251                         printk(KERN_ERR "EXT4-fs: "
2252                                "can't read group descriptor %d\n", i);
2253                         db_count = i;
2254                         goto failed_mount2;
2255                 }
2256         }
2257         if (!ext4_check_descriptors(sb)) {
2258                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2259                 goto failed_mount2;
2260         }
2261         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2262                 if (!ext4_fill_flex_info(sb)) {
2263                         printk(KERN_ERR
2264                                "EXT4-fs: unable to initialize "
2265                                "flex_bg meta info!\n");
2266                         goto failed_mount2;
2267                 }
2268
2269         sbi->s_gdb_count = db_count;
2270         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2271         spin_lock_init(&sbi->s_next_gen_lock);
2272
2273         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2274                         ext4_count_free_blocks(sb));
2275         if (!err) {
2276                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2277                                 ext4_count_free_inodes(sb));
2278         }
2279         if (!err) {
2280                 err = percpu_counter_init(&sbi->s_dirs_counter,
2281                                 ext4_count_dirs(sb));
2282         }
2283         if (!err) {
2284                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2285         }
2286         if (err) {
2287                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2288                 goto failed_mount3;
2289         }
2290
2291         sbi->s_stripe = ext4_get_stripe_size(sbi);
2292
2293         /*
2294          * set up enough so that it can read an inode
2295          */
2296         sb->s_op = &ext4_sops;
2297         sb->s_export_op = &ext4_export_ops;
2298         sb->s_xattr = ext4_xattr_handlers;
2299 #ifdef CONFIG_QUOTA
2300         sb->s_qcop = &ext4_qctl_operations;
2301         sb->dq_op = &ext4_quota_operations;
2302 #endif
2303         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2304
2305         sb->s_root = NULL;
2306
2307         needs_recovery = (es->s_last_orphan != 0 ||
2308                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2309                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2310
2311         /*
2312          * The first inode we look at is the journal inode.  Don't try
2313          * root first: it may be modified in the journal!
2314          */
2315         if (!test_opt(sb, NOLOAD) &&
2316             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2317                 if (ext4_load_journal(sb, es, journal_devnum))
2318                         goto failed_mount3;
2319                 if (!(sb->s_flags & MS_RDONLY) &&
2320                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2321                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2322                                "ext4_fill_super: Journal transaction "
2323                                "%u is corrupt\n", sb->s_id,
2324                                EXT4_SB(sb)->s_journal->j_failed_commit);
2325                         if (test_opt(sb, ERRORS_RO)) {
2326                                 printk(KERN_CRIT
2327                                        "Mounting filesystem read-only\n");
2328                                 sb->s_flags |= MS_RDONLY;
2329                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2330                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2331                         }
2332                         if (test_opt(sb, ERRORS_PANIC)) {
2333                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2334                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2335                                 ext4_commit_super(sb, es, 1);
2336                                 goto failed_mount4;
2337                         }
2338                 }
2339         } else if (journal_inum) {
2340                 if (ext4_create_journal(sb, es, journal_inum))
2341                         goto failed_mount3;
2342         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2343               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2344                 printk(KERN_ERR "EXT4-fs: required journal recovery "
2345                        "suppressed and not mounted read-only\n");
2346                 goto failed_mount4;
2347         } else {
2348                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2349                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2350                 sbi->s_journal = NULL;
2351                 needs_recovery = 0;
2352                 goto no_journal;
2353         }
2354
2355         if (ext4_blocks_count(es) > 0xffffffffULL &&
2356             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2357                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2358                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
2359                 goto failed_mount4;
2360         }
2361
2362         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2363                 jbd2_journal_set_features(sbi->s_journal,
2364                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2365                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2366         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2367                 jbd2_journal_set_features(sbi->s_journal,
2368                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2369                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2370                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2371         } else {
2372                 jbd2_journal_clear_features(sbi->s_journal,
2373                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2374                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2375         }
2376
2377         /* We have now updated the journal if required, so we can
2378          * validate the data journaling mode. */
2379         switch (test_opt(sb, DATA_FLAGS)) {
2380         case 0:
2381                 /* No mode set, assume a default based on the journal
2382                  * capabilities: ORDERED_DATA if the journal can
2383                  * cope, else JOURNAL_DATA
2384                  */
2385                 if (jbd2_journal_check_available_features
2386                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2387                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2388                 else
2389                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2390                 break;
2391
2392         case EXT4_MOUNT_ORDERED_DATA:
2393         case EXT4_MOUNT_WRITEBACK_DATA:
2394                 if (!jbd2_journal_check_available_features
2395                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2396                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2397                                "requested data journaling mode\n");
2398                         goto failed_mount4;
2399                 }
2400         default:
2401                 break;
2402         }
2403
2404 no_journal:
2405
2406         if (test_opt(sb, NOBH)) {
2407                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2408                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2409                                 "its supported only with writeback mode\n");
2410                         clear_opt(sbi->s_mount_opt, NOBH);
2411                 }
2412         }
2413         /*
2414          * The jbd2_journal_load will have done any necessary log recovery,
2415          * so we can safely mount the rest of the filesystem now.
2416          */
2417
2418         root = ext4_iget(sb, EXT4_ROOT_INO);
2419         if (IS_ERR(root)) {
2420                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2421                 ret = PTR_ERR(root);
2422                 goto failed_mount4;
2423         }
2424         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2425                 iput(root);
2426                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2427                 goto failed_mount4;
2428         }
2429         sb->s_root = d_alloc_root(root);
2430         if (!sb->s_root) {
2431                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2432                 iput(root);
2433                 ret = -ENOMEM;
2434                 goto failed_mount4;
2435         }
2436
2437         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2438
2439         /* determine the minimum size of new large inodes, if present */
2440         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2441                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2442                                                      EXT4_GOOD_OLD_INODE_SIZE;
2443                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2444                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2445                         if (sbi->s_want_extra_isize <
2446                             le16_to_cpu(es->s_want_extra_isize))
2447                                 sbi->s_want_extra_isize =
2448                                         le16_to_cpu(es->s_want_extra_isize);
2449                         if (sbi->s_want_extra_isize <
2450                             le16_to_cpu(es->s_min_extra_isize))
2451                                 sbi->s_want_extra_isize =
2452                                         le16_to_cpu(es->s_min_extra_isize);
2453                 }
2454         }
2455         /* Check if enough inode space is available */
2456         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2457                                                         sbi->s_inode_size) {
2458                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2459                                                        EXT4_GOOD_OLD_INODE_SIZE;
2460                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2461                         "available.\n");
2462         }
2463
2464         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2465                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2466                                 "requested data journaling mode\n");
2467                 clear_opt(sbi->s_mount_opt, DELALLOC);
2468         } else if (test_opt(sb, DELALLOC))
2469                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2470
2471         ext4_ext_init(sb);
2472         err = ext4_mb_init(sb, needs_recovery);
2473         if (err) {
2474                 printk(KERN_ERR "EXT4-fs: failed to initalize mballoc (%d)\n",
2475                        err);
2476                 goto failed_mount4;
2477         }
2478
2479         /*
2480          * akpm: core read_super() calls in here with the superblock locked.
2481          * That deadlocks, because orphan cleanup needs to lock the superblock
2482          * in numerous places.  Here we just pop the lock - it's relatively
2483          * harmless, because we are now ready to accept write_super() requests,
2484          * and aviro says that's the only reason for hanging onto the
2485          * superblock lock.
2486          */
2487         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2488         ext4_orphan_cleanup(sb, es);
2489         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2490         if (needs_recovery) {
2491                 printk(KERN_INFO "EXT4-fs: recovery complete.\n");
2492                 ext4_mark_recovery_complete(sb, es);
2493         }
2494         if (EXT4_SB(sb)->s_journal) {
2495                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2496                         descr = " journalled data mode";
2497                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2498                         descr = " ordered data mode";
2499                 else
2500                         descr = " writeback data mode";
2501         } else
2502                 descr = "out journal";
2503
2504         printk(KERN_INFO "EXT4-fs: mounted filesystem %s with%s\n",
2505                sb->s_id, descr);
2506
2507         lock_kernel();
2508         return 0;
2509
2510 cantfind_ext4:
2511         if (!silent)
2512                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2513                        sb->s_id);
2514         goto failed_mount;
2515
2516 failed_mount4:
2517         printk(KERN_ERR "EXT4-fs (device %s): mount failed\n", sb->s_id);
2518         if (sbi->s_journal) {
2519                 jbd2_journal_destroy(sbi->s_journal);
2520                 sbi->s_journal = NULL;
2521         }
2522 failed_mount3:
2523         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2524         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2525         percpu_counter_destroy(&sbi->s_dirs_counter);
2526         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2527 failed_mount2:
2528         for (i = 0; i < db_count; i++)
2529                 brelse(sbi->s_group_desc[i]);
2530         kfree(sbi->s_group_desc);
2531 failed_mount:
2532         if (sbi->s_proc) {
2533                 remove_proc_entry("inode_readahead_blks", sbi->s_proc);
2534                 remove_proc_entry(sb->s_id, ext4_proc_root);
2535         }
2536 #ifdef CONFIG_QUOTA
2537         for (i = 0; i < MAXQUOTAS; i++)
2538                 kfree(sbi->s_qf_names[i]);
2539 #endif
2540         ext4_blkdev_remove(sbi);
2541         brelse(bh);
2542 out_fail:
2543         sb->s_fs_info = NULL;
2544         kfree(sbi);
2545         lock_kernel();
2546         return ret;
2547 }
2548
2549 /*
2550  * Setup any per-fs journal parameters now.  We'll do this both on
2551  * initial mount, once the journal has been initialised but before we've
2552  * done any recovery; and again on any subsequent remount.
2553  */
2554 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2555 {
2556         struct ext4_sb_info *sbi = EXT4_SB(sb);
2557
2558         journal->j_commit_interval = sbi->s_commit_interval;
2559         journal->j_min_batch_time = sbi->s_min_batch_time;
2560         journal->j_max_batch_time = sbi->s_max_batch_time;
2561
2562         spin_lock(&journal->j_state_lock);
2563         if (test_opt(sb, BARRIER))
2564                 journal->j_flags |= JBD2_BARRIER;
2565         else
2566                 journal->j_flags &= ~JBD2_BARRIER;
2567         if (test_opt(sb, DATA_ERR_ABORT))
2568                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
2569         else
2570                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
2571         spin_unlock(&journal->j_state_lock);
2572 }
2573
2574 static journal_t *ext4_get_journal(struct super_block *sb,
2575                                    unsigned int journal_inum)
2576 {
2577         struct inode *journal_inode;
2578         journal_t *journal;
2579
2580         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2581
2582         /* First, test for the existence of a valid inode on disk.  Bad
2583          * things happen if we iget() an unused inode, as the subsequent
2584          * iput() will try to delete it. */
2585
2586         journal_inode = ext4_iget(sb, journal_inum);
2587         if (IS_ERR(journal_inode)) {
2588                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2589                 return NULL;
2590         }
2591         if (!journal_inode->i_nlink) {
2592                 make_bad_inode(journal_inode);
2593                 iput(journal_inode);
2594                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2595                 return NULL;
2596         }
2597
2598         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
2599                   journal_inode, journal_inode->i_size);
2600         if (!S_ISREG(journal_inode->i_mode)) {
2601                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2602                 iput(journal_inode);
2603                 return NULL;
2604         }
2605
2606         journal = jbd2_journal_init_inode(journal_inode);
2607         if (!journal) {
2608                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2609                 iput(journal_inode);
2610                 return NULL;
2611         }
2612         journal->j_private = sb;
2613         ext4_init_journal_params(sb, journal);
2614         return journal;
2615 }
2616
2617 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2618                                        dev_t j_dev)
2619 {
2620         struct buffer_head *bh;
2621         journal_t *journal;
2622         ext4_fsblk_t start;
2623         ext4_fsblk_t len;
2624         int hblock, blocksize;
2625         ext4_fsblk_t sb_block;
2626         unsigned long offset;
2627         struct ext4_super_block *es;
2628         struct block_device *bdev;
2629
2630         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2631
2632         bdev = ext4_blkdev_get(j_dev);
2633         if (bdev == NULL)
2634                 return NULL;
2635
2636         if (bd_claim(bdev, sb)) {
2637                 printk(KERN_ERR
2638                         "EXT4: failed to claim external journal device.\n");
2639                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
2640                 return NULL;
2641         }
2642
2643         blocksize = sb->s_blocksize;
2644         hblock = bdev_hardsect_size(bdev);
2645         if (blocksize < hblock) {
2646                 printk(KERN_ERR
2647                         "EXT4-fs: blocksize too small for journal device.\n");
2648                 goto out_bdev;
2649         }
2650
2651         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2652         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2653         set_blocksize(bdev, blocksize);
2654         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2655                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2656                        "external journal\n");
2657                 goto out_bdev;
2658         }
2659
2660         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2661         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2662             !(le32_to_cpu(es->s_feature_incompat) &
2663               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2664                 printk(KERN_ERR "EXT4-fs: external journal has "
2665                                         "bad superblock\n");
2666                 brelse(bh);
2667                 goto out_bdev;
2668         }
2669
2670         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2671                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2672                 brelse(bh);
2673                 goto out_bdev;
2674         }
2675
2676         len = ext4_blocks_count(es);
2677         start = sb_block + 1;
2678         brelse(bh);     /* we're done with the superblock */
2679
2680         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2681                                         start, len, blocksize);
2682         if (!journal) {
2683                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2684                 goto out_bdev;
2685         }
2686         journal->j_private = sb;
2687         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2688         wait_on_buffer(journal->j_sb_buffer);
2689         if (!buffer_uptodate(journal->j_sb_buffer)) {
2690                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2691                 goto out_journal;
2692         }
2693         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2694                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2695                                         "user (unsupported) - %d\n",
2696                         be32_to_cpu(journal->j_superblock->s_nr_users));
2697                 goto out_journal;
2698         }
2699         EXT4_SB(sb)->journal_bdev = bdev;
2700         ext4_init_journal_params(sb, journal);
2701         return journal;
2702 out_journal:
2703         jbd2_journal_destroy(journal);
2704 out_bdev:
2705         ext4_blkdev_put(bdev);
2706         return NULL;
2707 }
2708
2709 static int ext4_load_journal(struct super_block *sb,
2710                              struct ext4_super_block *es,
2711                              unsigned long journal_devnum)
2712 {
2713         journal_t *journal;
2714         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2715         dev_t journal_dev;
2716         int err = 0;
2717         int really_read_only;
2718
2719         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2720
2721         if (journal_devnum &&
2722             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2723                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2724                         "numbers have changed\n");
2725                 journal_dev = new_decode_dev(journal_devnum);
2726         } else
2727                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2728
2729         really_read_only = bdev_read_only(sb->s_bdev);
2730
2731         /*
2732          * Are we loading a blank journal or performing recovery after a
2733          * crash?  For recovery, we need to check in advance whether we
2734          * can get read-write access to the device.
2735          */
2736
2737         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2738                 if (sb->s_flags & MS_RDONLY) {
2739                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2740                                         "required on readonly filesystem.\n");
2741                         if (really_read_only) {
2742                                 printk(KERN_ERR "EXT4-fs: write access "
2743                                         "unavailable, cannot proceed.\n");
2744                                 return -EROFS;
2745                         }
2746                         printk(KERN_INFO "EXT4-fs: write access will "
2747                                "be enabled during recovery.\n");
2748                 }
2749         }
2750
2751         if (journal_inum && journal_dev) {
2752                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2753                        "and inode journals!\n");
2754                 return -EINVAL;
2755         }
2756
2757         if (journal_inum) {
2758                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2759                         return -EINVAL;
2760         } else {
2761                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2762                         return -EINVAL;
2763         }
2764
2765         if (journal->j_flags & JBD2_BARRIER)
2766                 printk(KERN_INFO "EXT4-fs: barriers enabled\n");
2767         else
2768                 printk(KERN_INFO "EXT4-fs: barriers disabled\n");
2769
2770         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2771                 err = jbd2_journal_update_format(journal);
2772                 if (err)  {
2773                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2774                         jbd2_journal_destroy(journal);
2775                         return err;
2776                 }
2777         }
2778
2779         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2780                 err = jbd2_journal_wipe(journal, !really_read_only);
2781         if (!err)
2782                 err = jbd2_journal_load(journal);
2783
2784         if (err) {
2785                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2786                 jbd2_journal_destroy(journal);
2787                 return err;
2788         }
2789
2790         EXT4_SB(sb)->s_journal = journal;
2791         ext4_clear_journal_err(sb, es);
2792
2793         if (journal_devnum &&
2794             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2795                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2796                 sb->s_dirt = 1;
2797
2798                 /* Make sure we flush the recovery flag to disk. */
2799                 ext4_commit_super(sb, es, 1);
2800         }
2801
2802         return 0;
2803 }
2804
2805 static int ext4_create_journal(struct super_block *sb,
2806                                struct ext4_super_block *es,
2807                                unsigned int journal_inum)
2808 {
2809         journal_t *journal;
2810         int err;
2811
2812         if (sb->s_flags & MS_RDONLY) {
2813                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2814                                 "create journal.\n");
2815                 return -EROFS;
2816         }
2817
2818         journal = ext4_get_journal(sb, journal_inum);
2819         if (!journal)
2820                 return -EINVAL;
2821
2822         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2823                journal_inum);
2824
2825         err = jbd2_journal_create(journal);
2826         if (err) {
2827                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2828                 jbd2_journal_destroy(journal);
2829                 return -EIO;
2830         }
2831
2832         EXT4_SB(sb)->s_journal = journal;
2833
2834         ext4_update_dynamic_rev(sb);
2835         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2836         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2837
2838         es->s_journal_inum = cpu_to_le32(journal_inum);
2839         sb->s_dirt = 1;
2840
2841         /* Make sure we flush the recovery flag to disk. */
2842         ext4_commit_super(sb, es, 1);
2843
2844         return 0;
2845 }
2846
2847 static void ext4_commit_super(struct super_block *sb,
2848                               struct ext4_super_block *es, int sync)
2849 {
2850         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2851
2852         if (!sbh)
2853                 return;
2854         if (buffer_write_io_error(sbh)) {
2855                 /*
2856                  * Oh, dear.  A previous attempt to write the
2857                  * superblock failed.  This could happen because the
2858                  * USB device was yanked out.  Or it could happen to
2859                  * be a transient write error and maybe the block will
2860                  * be remapped.  Nothing we can do but to retry the
2861                  * write and hope for the best.
2862                  */
2863                 printk(KERN_ERR "ext4: previous I/O error to "
2864                        "superblock detected for %s.\n", sb->s_id);
2865                 clear_buffer_write_io_error(sbh);
2866                 set_buffer_uptodate(sbh);
2867         }
2868         es->s_wtime = cpu_to_le32(get_seconds());
2869         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2870         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2871         BUFFER_TRACE(sbh, "marking dirty");
2872         mark_buffer_dirty(sbh);
2873         if (sync) {
2874                 sync_dirty_buffer(sbh);
2875                 if (buffer_write_io_error(sbh)) {
2876                         printk(KERN_ERR "ext4: I/O error while writing "
2877                                "superblock for %s.\n", sb->s_id);
2878                         clear_buffer_write_io_error(sbh);
2879                         set_buffer_uptodate(sbh);
2880                 }
2881         }
2882 }
2883
2884
2885 /*
2886  * Have we just finished recovery?  If so, and if we are mounting (or
2887  * remounting) the filesystem readonly, then we will end up with a
2888  * consistent fs on disk.  Record that fact.
2889  */
2890 static void ext4_mark_recovery_complete(struct super_block *sb,
2891                                         struct ext4_super_block *es)
2892 {
2893         journal_t *journal = EXT4_SB(sb)->s_journal;
2894
2895         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2896                 BUG_ON(journal != NULL);
2897                 return;
2898         }
2899         jbd2_journal_lock_updates(journal);
2900         if (jbd2_journal_flush(journal) < 0)
2901                 goto out;
2902
2903         lock_super(sb);
2904         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2905             sb->s_flags & MS_RDONLY) {
2906                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2907                 sb->s_dirt = 0;
2908                 ext4_commit_super(sb, es, 1);
2909         }
2910         unlock_super(sb);
2911
2912 out:
2913         jbd2_journal_unlock_updates(journal);
2914 }
2915
2916 /*
2917  * If we are mounting (or read-write remounting) a filesystem whose journal
2918  * has recorded an error from a previous lifetime, move that error to the
2919  * main filesystem now.
2920  */
2921 static void ext4_clear_journal_err(struct super_block *sb,
2922                                    struct ext4_super_block *es)
2923 {
2924         journal_t *journal;
2925         int j_errno;
2926         const char *errstr;
2927
2928         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2929
2930         journal = EXT4_SB(sb)->s_journal;
2931
2932         /*
2933          * Now check for any error status which may have been recorded in the
2934          * journal by a prior ext4_error() or ext4_abort()
2935          */
2936
2937         j_errno = jbd2_journal_errno(journal);
2938         if (j_errno) {
2939                 char nbuf[16];
2940
2941                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2942                 ext4_warning(sb, __func__, "Filesystem error recorded "
2943                              "from previous mount: %s", errstr);
2944                 ext4_warning(sb, __func__, "Marking fs in need of "
2945                              "filesystem check.");
2946
2947                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2948                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2949                 ext4_commit_super(sb, es, 1);
2950
2951                 jbd2_journal_clear_err(journal);
2952         }
2953 }
2954
2955 /*
2956  * Force the running and committing transactions to commit,
2957  * and wait on the commit.
2958  */
2959 int ext4_force_commit(struct super_block *sb)
2960 {
2961         journal_t *journal;
2962         int ret = 0;
2963
2964         if (sb->s_flags & MS_RDONLY)
2965                 return 0;
2966
2967         journal = EXT4_SB(sb)->s_journal;
2968         if (journal) {
2969                 sb->s_dirt = 0;
2970                 ret = ext4_journal_force_commit(journal);
2971         }
2972
2973         return ret;
2974 }
2975
2976 /*
2977  * Ext4 always journals updates to the superblock itself, so we don't
2978  * have to propagate any other updates to the superblock on disk at this
2979  * point.  (We can probably nuke this function altogether, and remove
2980  * any mention to sb->s_dirt in all of fs/ext4; eventual cleanup...)
2981  */
2982 static void ext4_write_super(struct super_block *sb)
2983 {
2984         if (EXT4_SB(sb)->s_journal) {
2985                 if (mutex_trylock(&sb->s_lock) != 0)
2986                         BUG();
2987                 sb->s_dirt = 0;
2988         } else {
2989                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2990         }
2991 }
2992
2993 static int ext4_sync_fs(struct super_block *sb, int wait)
2994 {
2995         int ret = 0;
2996
2997         trace_mark(ext4_sync_fs, "dev %s wait %d", sb->s_id, wait);
2998         sb->s_dirt = 0;
2999         if (EXT4_SB(sb)->s_journal) {
3000                 if (wait)
3001                         ret = ext4_force_commit(sb);
3002                 else
3003                         jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, NULL);
3004         } else {
3005                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, wait);
3006         }
3007         return ret;
3008 }
3009
3010 /*
3011  * LVM calls this function before a (read-only) snapshot is created.  This
3012  * gives us a chance to flush the journal completely and mark the fs clean.
3013  */
3014 static void ext4_write_super_lockfs(struct super_block *sb)
3015 {
3016         sb->s_dirt = 0;
3017
3018         if (!(sb->s_flags & MS_RDONLY)) {
3019                 journal_t *journal = EXT4_SB(sb)->s_journal;
3020
3021                 if (journal) {
3022                         /* Now we set up the journal barrier. */
3023                         jbd2_journal_lock_updates(journal);
3024
3025                         /*
3026                          * We don't want to clear needs_recovery flag when we
3027                          * failed to flush the journal.
3028                          */
3029                         if (jbd2_journal_flush(journal) < 0)
3030                                 return;
3031                 }
3032
3033                 /* Journal blocked and flushed, clear needs_recovery flag. */
3034                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3035                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
3036         }
3037 }
3038
3039 /*
3040  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3041  * flag here, even though the filesystem is not technically dirty yet.
3042  */
3043 static void ext4_unlockfs(struct super_block *sb)
3044 {
3045         if (EXT4_SB(sb)->s_journal && !(sb->s_flags & MS_RDONLY)) {
3046                 lock_super(sb);
3047                 /* Reser the needs_recovery flag before the fs is unlocked. */
3048                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3049                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
3050                 unlock_super(sb);
3051                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3052         }
3053 }
3054
3055 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3056 {
3057         struct ext4_super_block *es;
3058         struct ext4_sb_info *sbi = EXT4_SB(sb);
3059         ext4_fsblk_t n_blocks_count = 0;
3060         unsigned long old_sb_flags;
3061         struct ext4_mount_options old_opts;
3062         ext4_group_t g;
3063         int err;
3064 #ifdef CONFIG_QUOTA
3065         int i;
3066 #endif
3067
3068         /* Store the original options */
3069         old_sb_flags = sb->s_flags;
3070         old_opts.s_mount_opt = sbi->s_mount_opt;
3071         old_opts.s_resuid = sbi->s_resuid;
3072         old_opts.s_resgid = sbi->s_resgid;
3073         old_opts.s_commit_interval = sbi->s_commit_interval;
3074         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3075         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3076 #ifdef CONFIG_QUOTA
3077         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3078         for (i = 0; i < MAXQUOTAS; i++)
3079                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3080 #endif
3081
3082         /*
3083          * Allow the "check" option to be passed as a remount option.
3084          */
3085         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
3086                 err = -EINVAL;
3087                 goto restore_opts;
3088         }
3089
3090         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
3091                 ext4_abort(sb, __func__, "Abort forced by user");
3092
3093         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3094                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3095
3096         es = sbi->s_es;
3097
3098         if (sbi->s_journal)
3099                 ext4_init_journal_params(sb, sbi->s_journal);
3100
3101         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3102                 n_blocks_count > ext4_blocks_count(es)) {
3103                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3104                         err = -EROFS;
3105                         goto restore_opts;
3106                 }
3107
3108                 if (*flags & MS_RDONLY) {
3109                         /*
3110                          * First of all, the unconditional stuff we have to do
3111                          * to disable replay of the journal when we next remount
3112                          */
3113                         sb->s_flags |= MS_RDONLY;
3114
3115                         /*
3116                          * OK, test if we are remounting a valid rw partition
3117                          * readonly, and if so set the rdonly flag and then
3118                          * mark the partition as valid again.
3119                          */
3120                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3121                             (sbi->s_mount_state & EXT4_VALID_FS))
3122                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3123
3124                         /*
3125                          * We have to unlock super so that we can wait for
3126                          * transactions.
3127                          */
3128                         if (sbi->s_journal) {
3129                                 unlock_super(sb);
3130                                 ext4_mark_recovery_complete(sb, es);
3131                                 lock_super(sb);
3132                         }
3133                 } else {
3134                         __le32 ret;
3135                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3136                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3137                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3138                                        "remount RDWR because of unsupported "
3139                                        "optional features (%x).\n",
3140                                        sb->s_id, le32_to_cpu(ret));
3141                                 err = -EROFS;
3142                                 goto restore_opts;
3143                         }
3144
3145                         /*
3146                          * Make sure the group descriptor checksums
3147                          * are sane.  If they aren't, refuse to
3148                          * remount r/w.
3149                          */
3150                         for (g = 0; g < sbi->s_groups_count; g++) {
3151                                 struct ext4_group_desc *gdp =
3152                                         ext4_get_group_desc(sb, g, NULL);
3153
3154                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3155                                         printk(KERN_ERR
3156                "EXT4-fs: ext4_remount: "
3157                 "Checksum for group %lu failed (%u!=%u)\n",
3158                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3159                                                le16_to_cpu(gdp->bg_checksum));
3160                                         err = -EINVAL;
3161                                         goto restore_opts;
3162                                 }
3163                         }
3164
3165                         /*
3166                          * If we have an unprocessed orphan list hanging
3167                          * around from a previously readonly bdev mount,
3168                          * require a full umount/remount for now.
3169                          */
3170                         if (es->s_last_orphan) {
3171                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3172                                        "remount RDWR because of unprocessed "
3173                                        "orphan inode list.  Please "
3174                                        "umount/remount instead.\n",
3175                                        sb->s_id);
3176                                 err = -EINVAL;
3177                                 goto restore_opts;
3178                         }
3179
3180                         /*
3181                          * Mounting a RDONLY partition read-write, so reread
3182                          * and store the current valid flag.  (It may have
3183                          * been changed by e2fsck since we originally mounted
3184                          * the partition.)
3185                          */
3186                         if (sbi->s_journal)
3187                                 ext4_clear_journal_err(sb, es);
3188                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3189                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3190                                 goto restore_opts;
3191                         if (!ext4_setup_super(sb, es, 0))
3192                                 sb->s_flags &= ~MS_RDONLY;
3193                 }
3194         }
3195         if (sbi->s_journal == NULL)
3196                 ext4_commit_super(sb, es, 1);
3197
3198 #ifdef CONFIG_QUOTA
3199         /* Release old quota file names */
3200         for (i = 0; i < MAXQUOTAS; i++)
3201                 if (old_opts.s_qf_names[i] &&
3202                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3203                         kfree(old_opts.s_qf_names[i]);
3204 #endif
3205         return 0;
3206 restore_opts:
3207         sb->s_flags = old_sb_flags;
3208         sbi->s_mount_opt = old_opts.s_mount_opt;
3209         sbi->s_resuid = old_opts.s_resuid;
3210         sbi->s_resgid = old_opts.s_resgid;
3211         sbi->s_commit_interval = old_opts.s_commit_interval;
3212         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3213         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3214 #ifdef CONFIG_QUOTA
3215         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3216         for (i = 0; i < MAXQUOTAS; i++) {
3217                 if (sbi->s_qf_names[i] &&
3218                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3219                         kfree(sbi->s_qf_names[i]);
3220                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3221         }
3222 #endif
3223         return err;
3224 }
3225
3226 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3227 {
3228         struct super_block *sb = dentry->d_sb;
3229         struct ext4_sb_info *sbi = EXT4_SB(sb);
3230         struct ext4_super_block *es = sbi->s_es;
3231         u64 fsid;
3232
3233         if (test_opt(sb, MINIX_DF)) {
3234                 sbi->s_overhead_last = 0;
3235         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3236                 ext4_group_t ngroups = sbi->s_groups_count, i;
3237                 ext4_fsblk_t overhead = 0;
3238                 smp_rmb();
3239
3240                 /*
3241                  * Compute the overhead (FS structures).  This is constant
3242                  * for a given filesystem unless the number of block groups
3243                  * changes so we cache the previous value until it does.
3244                  */
3245
3246                 /*
3247                  * All of the blocks before first_data_block are
3248                  * overhead
3249                  */
3250                 overhead = le32_to_cpu(es->s_first_data_block);
3251
3252                 /*
3253                  * Add the overhead attributed to the superblock and
3254                  * block group descriptors.  If the sparse superblocks
3255                  * feature is turned on, then not all groups have this.
3256                  */
3257                 for (i = 0; i < ngroups; i++) {
3258                         overhead += ext4_bg_has_super(sb, i) +
3259                                 ext4_bg_num_gdb(sb, i);
3260                         cond_resched();
3261                 }
3262
3263                 /*
3264                  * Every block group has an inode bitmap, a block
3265                  * bitmap, and an inode table.
3266                  */
3267                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3268                 sbi->s_overhead_last = overhead;
3269                 smp_wmb();
3270                 sbi->s_blocks_last = ext4_blocks_count(es);
3271         }
3272
3273         buf->f_type = EXT4_SUPER_MAGIC;
3274         buf->f_bsize = sb->s_blocksize;
3275         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3276         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3277                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3278         ext4_free_blocks_count_set(es, buf->f_bfree);
3279         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3280         if (buf->f_bfree < ext4_r_blocks_count(es))
3281                 buf->f_bavail = 0;
3282         buf->f_files = le32_to_cpu(es->s_inodes_count);
3283         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3284         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3285         buf->f_namelen = EXT4_NAME_LEN;
3286         fsid = le64_to_cpup((void *)es->s_uuid) ^
3287                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3288         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3289         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3290         return 0;
3291 }
3292
3293 /* Helper function for writing quotas on sync - we need to start transaction before quota file
3294  * is locked for write. Otherwise the are possible deadlocks:
3295  * Process 1                         Process 2
3296  * ext4_create()                     quota_sync()
3297  *   jbd2_journal_start()                   write_dquot()
3298  *   DQUOT_INIT()                        down(dqio_mutex)
3299  *     down(dqio_mutex)                    jbd2_journal_start()
3300  *
3301  */
3302
3303 #ifdef CONFIG_QUOTA
3304
3305 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3306 {
3307         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3308 }
3309
3310 static int ext4_dquot_initialize(struct inode *inode, int type)
3311 {
3312         handle_t *handle;
3313         int ret, err;
3314
3315         /* We may create quota structure so we need to reserve enough blocks */
3316         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
3317         if (IS_ERR(handle))
3318                 return PTR_ERR(handle);
3319         ret = dquot_initialize(inode, type);
3320         err = ext4_journal_stop(handle);
3321         if (!ret)
3322                 ret = err;
3323         return ret;
3324 }
3325
3326 static int ext4_dquot_drop(struct inode *inode)
3327 {
3328         handle_t *handle;
3329         int ret, err;
3330
3331         /* We may delete quota structure so we need to reserve enough blocks */
3332         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
3333         if (IS_ERR(handle)) {
3334                 /*
3335                  * We call dquot_drop() anyway to at least release references
3336                  * to quota structures so that umount does not hang.
3337                  */
3338                 dquot_drop(inode);
3339                 return PTR_ERR(handle);
3340         }
3341         ret = dquot_drop(inode);
3342         err = ext4_journal_stop(handle);
3343         if (!ret)
3344                 ret = err;
3345         return ret;
3346 }
3347
3348 static int ext4_write_dquot(struct dquot *dquot)
3349 {
3350         int ret, err;
3351         handle_t *handle;
3352         struct inode *inode;
3353
3354         inode = dquot_to_inode(dquot);
3355         handle = ext4_journal_start(inode,
3356                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3357         if (IS_ERR(handle))
3358                 return PTR_ERR(handle);
3359         ret = dquot_commit(dquot);
3360         err = ext4_journal_stop(handle);
3361         if (!ret)
3362                 ret = err;
3363         return ret;
3364 }
3365
3366 static int ext4_acquire_dquot(struct dquot *dquot)
3367 {
3368         int ret, err;
3369         handle_t *handle;
3370
3371         handle = ext4_journal_start(dquot_to_inode(dquot),
3372                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3373         if (IS_ERR(handle))
3374                 return PTR_ERR(handle);
3375         ret = dquot_acquire(dquot);
3376         err = ext4_journal_stop(handle);
3377         if (!ret)
3378                 ret = err;
3379         return ret;
3380 }
3381
3382 static int ext4_release_dquot(struct dquot *dquot)
3383 {
3384         int ret, err;
3385         handle_t *handle;
3386
3387         handle = ext4_journal_start(dquot_to_inode(dquot),
3388                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3389         if (IS_ERR(handle)) {
3390                 /* Release dquot anyway to avoid endless cycle in dqput() */
3391                 dquot_release(dquot);
3392                 return PTR_ERR(handle);
3393         }
3394         ret = dquot_release(dquot);
3395         err = ext4_journal_stop(handle);
3396         if (!ret)
3397                 ret = err;
3398         return ret;
3399 }
3400
3401 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3402 {
3403         /* Are we journaling quotas? */
3404         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3405             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3406                 dquot_mark_dquot_dirty(dquot);
3407                 return ext4_write_dquot(dquot);
3408         } else {
3409                 return dquot_mark_dquot_dirty(dquot);
3410         }
3411 }
3412
3413 static int ext4_write_info(struct super_block *sb, int type)
3414 {
3415         int ret, err;
3416         handle_t *handle;
3417
3418         /* Data block + inode block */
3419         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3420         if (IS_ERR(handle))
3421                 return PTR_ERR(handle);
3422         ret = dquot_commit_info(sb, type);
3423         err = ext4_journal_stop(handle);
3424         if (!ret)
3425                 ret = err;
3426         return ret;
3427 }
3428
3429 /*
3430  * Turn on quotas during mount time - we need to find
3431  * the quota file and such...
3432  */
3433 static int ext4_quota_on_mount(struct super_block *sb, int type)
3434 {
3435         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3436                         EXT4_SB(sb)->s_jquota_fmt, type);
3437 }
3438
3439 /*
3440  * Standard function to be called on quota_on
3441  */
3442 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3443                          char *name, int remount)
3444 {
3445         int err;
3446         struct path path;
3447
3448         if (!test_opt(sb, QUOTA))
3449                 return -EINVAL;
3450         /* When remounting, no checks are needed and in fact, name is NULL */
3451         if (remount)
3452                 return vfs_quota_on(sb, type, format_id, name, remount);
3453
3454         err = kern_path(name, LOOKUP_FOLLOW, &path);
3455         if (err)
3456                 return err;
3457
3458         /* Quotafile not on the same filesystem? */
3459         if (path.mnt->mnt_sb != sb) {
3460                 path_put(&path);
3461                 return -EXDEV;
3462         }
3463         /* Journaling quota? */
3464         if (EXT4_SB(sb)->s_qf_names[type]) {
3465                 /* Quotafile not in fs root? */
3466                 if (path.dentry->d_parent != sb->s_root)
3467                         printk(KERN_WARNING
3468                                 "EXT4-fs: Quota file not on filesystem root. "
3469                                 "Journaled quota will not work.\n");
3470         }
3471
3472         /*
3473          * When we journal data on quota file, we have to flush journal to see
3474          * all updates to the file when we bypass pagecache...
3475          */
3476         if (EXT4_SB(sb)->s_journal &&
3477             ext4_should_journal_data(path.dentry->d_inode)) {
3478                 /*
3479                  * We don't need to lock updates but journal_flush() could
3480                  * otherwise be livelocked...
3481                  */
3482                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3483                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3484                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3485                 if (err) {
3486                         path_put(&path);
3487                         return err;
3488                 }
3489         }
3490
3491         err = vfs_quota_on_path(sb, type, format_id, &path);
3492         path_put(&path);
3493         return err;
3494 }
3495
3496 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3497  * acquiring the locks... As quota files are never truncated and quota code
3498  * itself serializes the operations (and noone else should touch the files)
3499  * we don't have to be afraid of races */
3500 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3501                                size_t len, loff_t off)
3502 {
3503         struct inode *inode = sb_dqopt(sb)->files[type];
3504         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3505         int err = 0;
3506         int offset = off & (sb->s_blocksize - 1);
3507         int tocopy;
3508         size_t toread;
3509         struct buffer_head *bh;
3510         loff_t i_size = i_size_read(inode);
3511
3512         if (off > i_size)
3513                 return 0;
3514         if (off+len > i_size)
3515                 len = i_size-off;
3516         toread = len;
3517         while (toread > 0) {
3518                 tocopy = sb->s_blocksize - offset < toread ?
3519                                 sb->s_blocksize - offset : toread;
3520                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3521                 if (err)
3522                         return err;
3523                 if (!bh)        /* A hole? */
3524                         memset(data, 0, tocopy);
3525                 else
3526                         memcpy(data, bh->b_data+offset, tocopy);
3527                 brelse(bh);
3528                 offset = 0;
3529                 toread -= tocopy;
3530                 data += tocopy;
3531                 blk++;
3532         }
3533         return len;
3534 }
3535
3536 /* Write to quotafile (we know the transaction is already started and has
3537  * enough credits) */
3538 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3539                                 const char *data, size_t len, loff_t off)
3540 {
3541         struct inode *inode = sb_dqopt(sb)->files[type];
3542         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3543         int err = 0;
3544         int offset = off & (sb->s_blocksize - 1);
3545         int tocopy;
3546         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3547         size_t towrite = len;
3548         struct buffer_head *bh;
3549         handle_t *handle = journal_current_handle();
3550
3551         if (EXT4_SB(sb)->s_journal && !handle) {
3552                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%llu, len=%llu)"
3553                         " cancelled because transaction is not started.\n",
3554                         (unsigned long long)off, (unsigned long long)len);
3555                 return -EIO;
3556         }
3557         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3558         while (towrite > 0) {
3559                 tocopy = sb->s_blocksize - offset < towrite ?
3560                                 sb->s_blocksize - offset : towrite;
3561                 bh = ext4_bread(handle, inode, blk, 1, &err);
3562                 if (!bh)
3563                         goto out;
3564                 if (journal_quota) {
3565                         err = ext4_journal_get_write_access(handle, bh);
3566                         if (err) {
3567                                 brelse(bh);
3568                                 goto out;
3569                         }
3570                 }
3571                 lock_buffer(bh);
3572                 memcpy(bh->b_data+offset, data, tocopy);
3573                 flush_dcache_page(bh->b_page);
3574                 unlock_buffer(bh);
3575                 if (journal_quota)
3576                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3577                 else {
3578                         /* Always do at least ordered writes for quotas */
3579                         err = ext4_jbd2_file_inode(handle, inode);
3580                         mark_buffer_dirty(bh);
3581                 }
3582                 brelse(bh);
3583                 if (err)
3584                         goto out;
3585                 offset = 0;
3586                 towrite -= tocopy;
3587                 data += tocopy;
3588                 blk++;
3589         }
3590 out:
3591         if (len == towrite) {
3592                 mutex_unlock(&inode->i_mutex);
3593                 return err;
3594         }
3595         if (inode->i_size < off+len-towrite) {
3596                 i_size_write(inode, off+len-towrite);
3597                 EXT4_I(inode)->i_disksize = inode->i_size;
3598         }
3599         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3600         ext4_mark_inode_dirty(handle, inode);
3601         mutex_unlock(&inode->i_mutex);
3602         return len - towrite;
3603 }
3604
3605 #endif
3606
3607 static int ext4_get_sb(struct file_system_type *fs_type,
3608         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3609 {
3610         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3611 }
3612
3613 #ifdef CONFIG_PROC_FS
3614 static int ext4_ui_proc_show(struct seq_file *m, void *v)
3615 {
3616         unsigned int *p = m->private;
3617
3618         seq_printf(m, "%u\n", *p);
3619         return 0;
3620 }
3621
3622 static int ext4_ui_proc_open(struct inode *inode, struct file *file)
3623 {
3624         return single_open(file, ext4_ui_proc_show, PDE(inode)->data);
3625 }
3626
3627 static ssize_t ext4_ui_proc_write(struct file *file, const char __user *buf,
3628                                size_t cnt, loff_t *ppos)
3629 {
3630         unsigned long *p = PDE(file->f_path.dentry->d_inode)->data;
3631         char str[32];
3632
3633         if (cnt >= sizeof(str))
3634                 return -EINVAL;
3635         if (copy_from_user(str, buf, cnt))
3636                 return -EFAULT;
3637
3638         *p = simple_strtoul(str, NULL, 0);
3639         return cnt;
3640 }
3641
3642 const struct file_operations ext4_ui_proc_fops = {
3643         .owner          = THIS_MODULE,
3644         .open           = ext4_ui_proc_open,
3645         .read           = seq_read,
3646         .llseek         = seq_lseek,
3647         .release        = single_release,
3648         .write          = ext4_ui_proc_write,
3649 };
3650 #endif
3651
3652 static struct file_system_type ext4_fs_type = {
3653         .owner          = THIS_MODULE,
3654         .name           = "ext4",
3655         .get_sb         = ext4_get_sb,
3656         .kill_sb        = kill_block_super,
3657         .fs_flags       = FS_REQUIRES_DEV,
3658 };
3659
3660 #ifdef CONFIG_EXT4DEV_COMPAT
3661 static int ext4dev_get_sb(struct file_system_type *fs_type,
3662         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3663 {
3664         printk(KERN_WARNING "EXT4-fs: Update your userspace programs "
3665                "to mount using ext4\n");
3666         printk(KERN_WARNING "EXT4-fs: ext4dev backwards compatibility "
3667                "will go away by 2.6.31\n");
3668         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3669 }
3670
3671 static struct file_system_type ext4dev_fs_type = {
3672         .owner          = THIS_MODULE,
3673         .name           = "ext4dev",
3674         .get_sb         = ext4dev_get_sb,
3675         .kill_sb        = kill_block_super,
3676         .fs_flags       = FS_REQUIRES_DEV,
3677 };
3678 MODULE_ALIAS("ext4dev");
3679 #endif
3680
3681 static int __init init_ext4_fs(void)
3682 {
3683         int err;
3684
3685         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
3686         err = init_ext4_mballoc();
3687         if (err)
3688                 return err;
3689
3690         err = init_ext4_xattr();
3691         if (err)
3692                 goto out2;
3693         err = init_inodecache();
3694         if (err)
3695                 goto out1;
3696         err = register_filesystem(&ext4_fs_type);
3697         if (err)
3698                 goto out;
3699 #ifdef CONFIG_EXT4DEV_COMPAT
3700         err = register_filesystem(&ext4dev_fs_type);
3701         if (err) {
3702                 unregister_filesystem(&ext4_fs_type);
3703                 goto out;
3704         }
3705 #endif
3706         return 0;
3707 out:
3708         destroy_inodecache();
3709 out1:
3710         exit_ext4_xattr();
3711 out2:
3712         exit_ext4_mballoc();
3713         return err;
3714 }
3715
3716 static void __exit exit_ext4_fs(void)
3717 {
3718         unregister_filesystem(&ext4_fs_type);
3719 #ifdef CONFIG_EXT4DEV_COMPAT
3720         unregister_filesystem(&ext4dev_fs_type);
3721 #endif
3722         destroy_inodecache();
3723         exit_ext4_xattr();
3724         exit_ext4_mballoc();
3725         remove_proc_entry("fs/ext4", NULL);
3726 }
3727
3728 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
3729 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
3730 MODULE_LICENSE("GPL");
3731 module_init(init_ext4_fs)
3732 module_exit(exit_ext4_fs)