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/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/smp_lock.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/proc_fs.h>
  39 #include <linux/ctype.h>
  40 #include <linux/log2.h>
  41 #include <linux/crc16.h>
  42 #include <asm/uaccess.h>
  43
  44 #include "ext4.h"
  45 #include "ext4_jbd2.h"
  46 #include "xattr.h"
  47 #include "acl.h"
  48 #include "mballoc.h"
  49
  50 #define CREATE_TRACE_POINTS
  51 #include <trace/events/ext4.h>
  52
  53 static int default_mb_history_length = 1000;
  54
  55 module_param_named(default_mb_history_length, default_mb_history_length,
  56                    int, 0644);
  57 MODULE_PARM_DESC(default_mb_history_length,
  58                  "Default number of entries saved for mb_history");
  59
  60 struct proc_dir_entry *ext4_proc_root;
  61 static struct kset *ext4_kset;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_commit_super(struct super_block *sb, int sync);
  66 static void ext4_mark_recovery_complete(struct super_block *sb,
  67                                         struct ext4_super_block *es);
  68 static void ext4_clear_journal_err(struct super_block *sb,
  69                                    struct ext4_super_block *es);
  70 static int ext4_sync_fs(struct super_block *sb, int wait);
  71 static const char *ext4_decode_error(struct super_block *sb, int errno,
  72                                      char nbuf[16]);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static void ext4_write_super(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78
  79
  80 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  81                                struct ext4_group_desc *bg)
  82 {
  83         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  84                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  85                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  86 }
  87
  88 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  89                                struct ext4_group_desc *bg)
  90 {
  91         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  92                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  93                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  94 }
  95
  96 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  97                               struct ext4_group_desc *bg)
  98 {
  99         return le32_to_cpu(bg->bg_inode_table_lo) |
 100                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 101                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 102 }
 103
 104 __u32 ext4_free_blks_count(struct super_block *sb,
 105                               struct ext4_group_desc *bg)
 106 {
 107         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 108                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 109                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 110 }
 111
 112 __u32 ext4_free_inodes_count(struct super_block *sb,
 113                               struct ext4_group_desc *bg)
 114 {
 115         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 116                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 117                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 118 }
 119
 120 __u32 ext4_used_dirs_count(struct super_block *sb,
 121                               struct ext4_group_desc *bg)
 122 {
 123         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 124                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 125                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 126 }
 127
 128 __u32 ext4_itable_unused_count(struct super_block *sb,
 129                               struct ext4_group_desc *bg)
 130 {
 131         return le16_to_cpu(bg->bg_itable_unused_lo) |
 132                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 133                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 134 }
 135
 136 void ext4_block_bitmap_set(struct super_block *sb,
 137                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 138 {
 139         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 140         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 141                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 142 }
 143
 144 void ext4_inode_bitmap_set(struct super_block *sb,
 145                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 146 {
 147         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 148         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 149                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 150 }
 151
 152 void ext4_inode_table_set(struct super_block *sb,
 153                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 154 {
 155         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 156         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 157                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 158 }
 159
 160 void ext4_free_blks_set(struct super_block *sb,
 161                           struct ext4_group_desc *bg, __u32 count)
 162 {
 163         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 164         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 165                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 166 }
 167
 168 void ext4_free_inodes_set(struct super_block *sb,
 169                           struct ext4_group_desc *bg, __u32 count)
 170 {
 171         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 172         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 173                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 174 }
 175
 176 void ext4_used_dirs_set(struct super_block *sb,
 177                           struct ext4_group_desc *bg, __u32 count)
 178 {
 179         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 180         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 181                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 182 }
 183
 184 void ext4_itable_unused_set(struct super_block *sb,
 185                           struct ext4_group_desc *bg, __u32 count)
 186 {
 187         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 188         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 189                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 190 }
 191
 192 /*
 193  * Wrappers for jbd2_journal_start/end.
 194  *
 195  * The only special thing we need to do here is to make sure that all
 196  * journal_end calls result in the superblock being marked dirty, so
 197  * that sync() will call the filesystem's write_super callback if
 198  * appropriate.
 199  */
 200 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 201 {
 202         journal_t *journal;
 203
 204         if (sb->s_flags & MS_RDONLY)
 205                 return ERR_PTR(-EROFS);
 206
 207         /* Special case here: if the journal has aborted behind our
 208          * backs (eg. EIO in the commit thread), then we still need to
 209          * take the FS itself readonly cleanly. */
 210         journal = EXT4_SB(sb)->s_journal;
 211         if (journal) {
 212                 if (is_journal_aborted(journal)) {
 213                         ext4_abort(sb, __func__, "Detected aborted journal");
 214                         return ERR_PTR(-EROFS);
 215                 }
 216                 return jbd2_journal_start(journal, nblocks);
 217         }
 218         /*
 219          * We're not journaling, return the appropriate indication.
 220          */
 221         current->journal_info = EXT4_NOJOURNAL_HANDLE;
 222         return current->journal_info;
 223 }
 224
 225 /*
 226  * The only special thing we need to do here is to make sure that all
 227  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 228  * that sync() will call the filesystem's write_super callback if
 229  * appropriate.
 230  */
 231 int __ext4_journal_stop(const char *where, handle_t *handle)
 232 {
 233         struct super_block *sb;
 234         int err;
 235         int rc;
 236
 237         if (!ext4_handle_valid(handle)) {
 238                 /*
 239                  * Do this here since we don't call jbd2_journal_stop() in
 240                  * no-journal mode.
 241                  */
 242                 current->journal_info = NULL;
 243                 return 0;
 244         }
 245         sb = handle->h_transaction->t_journal->j_private;
 246         err = handle->h_err;
 247         rc = jbd2_journal_stop(handle);
 248
 249         if (!err)
 250                 err = rc;
 251         if (err)
 252                 __ext4_std_error(sb, where, err);
 253         return err;
 254 }
 255
 256 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 257                 struct buffer_head *bh, handle_t *handle, int err)
 258 {
 259         char nbuf[16];
 260         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 261
 262         BUG_ON(!ext4_handle_valid(handle));
 263
 264         if (bh)
 265                 BUFFER_TRACE(bh, "abort");
 266
 267         if (!handle->h_err)
 268                 handle->h_err = err;
 269
 270         if (is_handle_aborted(handle))
 271                 return;
 272
 273         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 274                caller, errstr, err_fn);
 275
 276         jbd2_journal_abort_handle(handle);
 277 }
 278
 279 /* Deal with the reporting of failure conditions on a filesystem such as
 280  * inconsistencies detected or read IO failures.
 281  *
 282  * On ext2, we can store the error state of the filesystem in the
 283  * superblock.  That is not possible on ext4, because we may have other
 284  * write ordering constraints on the superblock which prevent us from
 285  * writing it out straight away; and given that the journal is about to
 286  * be aborted, we can't rely on the current, or future, transactions to
 287  * write out the superblock safely.
 288  *
 289  * We'll just use the jbd2_journal_abort() error code to record an error in
 290  * the journal instead.  On recovery, the journal will compain about
 291  * that error until we've noted it down and cleared it.
 292  */
 293
 294 static void ext4_handle_error(struct super_block *sb)
 295 {
 296         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 297
 298         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 299         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 300
 301         if (sb->s_flags & MS_RDONLY)
 302                 return;
 303
 304         if (!test_opt(sb, ERRORS_CONT)) {
 305                 journal_t *journal = EXT4_SB(sb)->s_journal;
 306
 307                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 308                 if (journal)
 309                         jbd2_journal_abort(journal, -EIO);
 310         }
 311         if (test_opt(sb, ERRORS_RO)) {
 312                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 313                 sb->s_flags |= MS_RDONLY;
 314         }
 315         ext4_commit_super(sb, 1);
 316         if (test_opt(sb, ERRORS_PANIC))
 317                 panic("EXT4-fs (device %s): panic forced after error\n",
 318                         sb->s_id);
 319 }
 320
 321 void ext4_error(struct super_block *sb, const char *function,
 322                 const char *fmt, ...)
 323 {
 324         va_list args;
 325
 326         va_start(args, fmt);
 327         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 328         vprintk(fmt, args);
 329         printk("\n");
 330         va_end(args);
 331
 332         ext4_handle_error(sb);
 333 }
 334
 335 static const char *ext4_decode_error(struct super_block *sb, int errno,
 336                                      char nbuf[16])
 337 {
 338         char *errstr = NULL;
 339
 340         switch (errno) {
 341         case -EIO:
 342                 errstr = "IO failure";
 343                 break;
 344         case -ENOMEM:
 345                 errstr = "Out of memory";
 346                 break;
 347         case -EROFS:
 348                 if (!sb || (EXT4_SB(sb)->s_journal &&
 349                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 350                         errstr = "Journal has aborted";
 351                 else
 352                         errstr = "Readonly filesystem";
 353                 break;
 354         default:
 355                 /* If the caller passed in an extra buffer for unknown
 356                  * errors, textualise them now.  Else we just return
 357                  * NULL. */
 358                 if (nbuf) {
 359                         /* Check for truncated error codes... */
 360                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 361                                 errstr = nbuf;
 362                 }
 363                 break;
 364         }
 365
 366         return errstr;
 367 }
 368
 369 /* __ext4_std_error decodes expected errors from journaling functions
 370  * automatically and invokes the appropriate error response.  */
 371
 372 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 373 {
 374         char nbuf[16];
 375         const char *errstr;
 376
 377         /* Special case: if the error is EROFS, and we're not already
 378          * inside a transaction, then there's really no point in logging
 379          * an error. */
 380         if (errno == -EROFS && journal_current_handle() == NULL &&
 381             (sb->s_flags & MS_RDONLY))
 382                 return;
 383
 384         errstr = ext4_decode_error(sb, errno, nbuf);
 385         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 386                sb->s_id, function, errstr);
 387
 388         ext4_handle_error(sb);
 389 }
 390
 391 /*
 392  * ext4_abort is a much stronger failure handler than ext4_error.  The
 393  * abort function may be used to deal with unrecoverable failures such
 394  * as journal IO errors or ENOMEM at a critical moment in log management.
 395  *
 396  * We unconditionally force the filesystem into an ABORT|READONLY state,
 397  * unless the error response on the fs has been set to panic in which
 398  * case we take the easy way out and panic immediately.
 399  */
 400
 401 void ext4_abort(struct super_block *sb, const char *function,
 402                 const char *fmt, ...)
 403 {
 404         va_list args;
 405
 406         va_start(args, fmt);
 407         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 408         vprintk(fmt, args);
 409         printk("\n");
 410         va_end(args);
 411
 412         if (test_opt(sb, ERRORS_PANIC))
 413                 panic("EXT4-fs panic from previous error\n");
 414
 415         if (sb->s_flags & MS_RDONLY)
 416                 return;
 417
 418         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 419         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 420         sb->s_flags |= MS_RDONLY;
 421         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 422         if (EXT4_SB(sb)->s_journal)
 423                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 424 }
 425
 426 void ext4_msg (struct super_block * sb, const char *prefix,
 427                    const char *fmt, ...)
 428 {
 429         va_list args;
 430
 431         va_start(args, fmt);
 432         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
 433         vprintk(fmt, args);
 434         printk("\n");
 435         va_end(args);
 436 }
 437
 438 void ext4_warning(struct super_block *sb, const char *function,
 439                   const char *fmt, ...)
 440 {
 441         va_list args;
 442
 443         va_start(args, fmt);
 444         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 445                sb->s_id, function);
 446         vprintk(fmt, args);
 447         printk("\n");
 448         va_end(args);
 449 }
 450
 451 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
 452                            const char *function, const char *fmt, ...)
 453 __releases(bitlock)
 454 __acquires(bitlock)
 455 {
 456         va_list args;
 457         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 458
 459         va_start(args, fmt);
 460         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 461         vprintk(fmt, args);
 462         printk("\n");
 463         va_end(args);
 464
 465         if (test_opt(sb, ERRORS_CONT)) {
 466                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 467                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 468                 ext4_commit_super(sb, 0);
 469                 return;
 470         }
 471         ext4_unlock_group(sb, grp);
 472         ext4_handle_error(sb);
 473         /*
 474          * We only get here in the ERRORS_RO case; relocking the group
 475          * may be dangerous, but nothing bad will happen since the
 476          * filesystem will have already been marked read/only and the
 477          * journal has been aborted.  We return 1 as a hint to callers
 478          * who might what to use the return value from
 479          * ext4_grp_locked_error() to distinguish beween the
 480          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 481          * aggressively from the ext4 function in question, with a
 482          * more appropriate error code.
 483          */
 484         ext4_lock_group(sb, grp);
 485         return;
 486 }
 487
 488 void ext4_update_dynamic_rev(struct super_block *sb)
 489 {
 490         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 491
 492         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 493                 return;
 494
 495         ext4_warning(sb, __func__,
 496                      "updating to rev %d because of new feature flag, "
 497                      "running e2fsck is recommended",
 498                      EXT4_DYNAMIC_REV);
 499
 500         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 501         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 502         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 503         /* leave es->s_feature_*compat flags alone */
 504         /* es->s_uuid will be set by e2fsck if empty */
 505
 506         /*
 507          * The rest of the superblock fields should be zero, and if not it
 508          * means they are likely already in use, so leave them alone.  We
 509          * can leave it up to e2fsck to clean up any inconsistencies there.
 510          */
 511 }
 512
 513 /*
 514  * Open the external journal device
 515  */
 516 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 517 {
 518         struct block_device *bdev;
 519         char b[BDEVNAME_SIZE];
 520
 521         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 522         if (IS_ERR(bdev))
 523                 goto fail;
 524         return bdev;
 525
 526 fail:
 527         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 528                         __bdevname(dev, b), PTR_ERR(bdev));
 529         return NULL;
 530 }
 531
 532 /*
 533  * Release the journal device
 534  */
 535 static int ext4_blkdev_put(struct block_device *bdev)
 536 {
 537         bd_release(bdev);
 538         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 539 }
 540
 541 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 542 {
 543         struct block_device *bdev;
 544         int ret = -ENODEV;
 545
 546         bdev = sbi->journal_bdev;
 547         if (bdev) {
 548                 ret = ext4_blkdev_put(bdev);
 549                 sbi->journal_bdev = NULL;
 550         }
 551         return ret;
 552 }
 553
 554 static inline struct inode *orphan_list_entry(struct list_head *l)
 555 {
 556         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 557 }
 558
 559 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 560 {
 561         struct list_head *l;
 562
 563         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 564                  le32_to_cpu(sbi->s_es->s_last_orphan));
 565
 566         printk(KERN_ERR "sb_info orphan list:\n");
 567         list_for_each(l, &sbi->s_orphan) {
 568                 struct inode *inode = orphan_list_entry(l);
 569                 printk(KERN_ERR "  "
 570                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 571                        inode->i_sb->s_id, inode->i_ino, inode,
 572                        inode->i_mode, inode->i_nlink,
 573                        NEXT_ORPHAN(inode));
 574         }
 575 }
 576
 577 static void ext4_put_super(struct super_block *sb)
 578 {
 579         struct ext4_sb_info *sbi = EXT4_SB(sb);
 580         struct ext4_super_block *es = sbi->s_es;
 581         int i, err;
 582
 583         lock_super(sb);
 584         lock_kernel();
 585         if (sb->s_dirt)
 586                 ext4_commit_super(sb, 1);
 587
 588         ext4_release_system_zone(sb);
 589         ext4_mb_release(sb);
 590         ext4_ext_release(sb);
 591         ext4_xattr_put_super(sb);
 592         if (sbi->s_journal) {
 593                 err = jbd2_journal_destroy(sbi->s_journal);
 594                 sbi->s_journal = NULL;
 595                 if (err < 0)
 596                         ext4_abort(sb, __func__,
 597                                    "Couldn't clean up the journal");
 598         }
 599         if (!(sb->s_flags & MS_RDONLY)) {
 600                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 601                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 602                 ext4_commit_super(sb, 1);
 603         }
 604         if (sbi->s_proc) {
 605                 remove_proc_entry(sb->s_id, ext4_proc_root);
 606         }
 607         kobject_del(&sbi->s_kobj);
 608
 609         for (i = 0; i < sbi->s_gdb_count; i++)
 610                 brelse(sbi->s_group_desc[i]);
 611         kfree(sbi->s_group_desc);
 612         if (is_vmalloc_addr(sbi->s_flex_groups))
 613                 vfree(sbi->s_flex_groups);
 614         else
 615                 kfree(sbi->s_flex_groups);
 616         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 617         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 618         percpu_counter_destroy(&sbi->s_dirs_counter);
 619         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 620         brelse(sbi->s_sbh);
 621 #ifdef CONFIG_QUOTA
 622         for (i = 0; i < MAXQUOTAS; i++)
 623                 kfree(sbi->s_qf_names[i]);
 624 #endif
 625
 626         /* Debugging code just in case the in-memory inode orphan list
 627          * isn't empty.  The on-disk one can be non-empty if we've
 628          * detected an error and taken the fs readonly, but the
 629          * in-memory list had better be clean by this point. */
 630         if (!list_empty(&sbi->s_orphan))
 631                 dump_orphan_list(sb, sbi);
 632         J_ASSERT(list_empty(&sbi->s_orphan));
 633
 634         invalidate_bdev(sb->s_bdev);
 635         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 636                 /*
 637                  * Invalidate the journal device's buffers.  We don't want them
 638                  * floating about in memory - the physical journal device may
 639                  * hotswapped, and it breaks the `ro-after' testing code.
 640                  */
 641                 sync_blockdev(sbi->journal_bdev);
 642                 invalidate_bdev(sbi->journal_bdev);
 643                 ext4_blkdev_remove(sbi);
 644         }
 645         sb->s_fs_info = NULL;
 646         /*
 647          * Now that we are completely done shutting down the
 648          * superblock, we need to actually destroy the kobject.
 649          */
 650         unlock_kernel();
 651         unlock_super(sb);
 652         kobject_put(&sbi->s_kobj);
 653         wait_for_completion(&sbi->s_kobj_unregister);
 654         kfree(sbi->s_blockgroup_lock);
 655         kfree(sbi);
 656 }
 657
 658 static struct kmem_cache *ext4_inode_cachep;
 659
 660 /*
 661  * Called inside transaction, so use GFP_NOFS
 662  */
 663 static struct inode *ext4_alloc_inode(struct super_block *sb)
 664 {
 665         struct ext4_inode_info *ei;
 666
 667         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 668         if (!ei)
 669                 return NULL;
 670
 671         ei->vfs_inode.i_version = 1;
 672         ei->vfs_inode.i_data.writeback_index = 0;
 673         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 674         INIT_LIST_HEAD(&ei->i_prealloc_list);
 675         spin_lock_init(&ei->i_prealloc_lock);
 676         /*
 677          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 678          * therefore it can be null here.  Don't check it, just initialize
 679          * jinode.
 680          */
 681         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 682         ei->i_reserved_data_blocks = 0;
 683         ei->i_reserved_meta_blocks = 0;
 684         ei->i_allocated_meta_blocks = 0;
 685         ei->i_delalloc_reserved_flag = 0;
 686         spin_lock_init(&(ei->i_block_reservation_lock));
 687
 688         return &ei->vfs_inode;
 689 }
 690
 691 static void ext4_destroy_inode(struct inode *inode)
 692 {
 693         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 694                 ext4_msg(inode->i_sb, KERN_ERR,
 695                          "Inode %lu (%p): orphan list check failed!",
 696                          inode->i_ino, EXT4_I(inode));
 697                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 698                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 699                                 true);
 700                 dump_stack();
 701         }
 702         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 703 }
 704
 705 static void init_once(void *foo)
 706 {
 707         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 708
 709         INIT_LIST_HEAD(&ei->i_orphan);
 710 #ifdef CONFIG_EXT4_FS_XATTR
 711         init_rwsem(&ei->xattr_sem);
 712 #endif
 713         init_rwsem(&ei->i_data_sem);
 714         inode_init_once(&ei->vfs_inode);
 715 }
 716
 717 static int init_inodecache(void)
 718 {
 719         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 720                                              sizeof(struct ext4_inode_info),
 721                                              0, (SLAB_RECLAIM_ACCOUNT|
 722                                                 SLAB_MEM_SPREAD),
 723                                              init_once);
 724         if (ext4_inode_cachep == NULL)
 725                 return -ENOMEM;
 726         return 0;
 727 }
 728
 729 static void destroy_inodecache(void)
 730 {
 731         kmem_cache_destroy(ext4_inode_cachep);
 732 }
 733
 734 static void ext4_clear_inode(struct inode *inode)
 735 {
 736         ext4_discard_preallocations(inode);
 737         if (EXT4_JOURNAL(inode))
 738                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 739                                        &EXT4_I(inode)->jinode);
 740 }
 741
 742 static inline void ext4_show_quota_options(struct seq_file *seq,
 743                                            struct super_block *sb)
 744 {
 745 #if defined(CONFIG_QUOTA)
 746         struct ext4_sb_info *sbi = EXT4_SB(sb);
 747
 748         if (sbi->s_jquota_fmt)
 749                 seq_printf(seq, ",jqfmt=%s",
 750                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 751
 752         if (sbi->s_qf_names[USRQUOTA])
 753                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 754
 755         if (sbi->s_qf_names[GRPQUOTA])
 756                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 757
 758         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 759                 seq_puts(seq, ",usrquota");
 760
 761         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 762                 seq_puts(seq, ",grpquota");
 763 #endif
 764 }
 765
 766 /*
 767  * Show an option if
 768  *  - it's set to a non-default value OR
 769  *  - if the per-sb default is different from the global default
 770  */
 771 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 772 {
 773         int def_errors;
 774         unsigned long def_mount_opts;
 775         struct super_block *sb = vfs->mnt_sb;
 776         struct ext4_sb_info *sbi = EXT4_SB(sb);
 777         struct ext4_super_block *es = sbi->s_es;
 778
 779         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 780         def_errors     = le16_to_cpu(es->s_errors);
 781
 782         if (sbi->s_sb_block != 1)
 783                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 784         if (test_opt(sb, MINIX_DF))
 785                 seq_puts(seq, ",minixdf");
 786         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 787                 seq_puts(seq, ",grpid");
 788         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 789                 seq_puts(seq, ",nogrpid");
 790         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 791             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 792                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 793         }
 794         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 795             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 796                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 797         }
 798         if (test_opt(sb, ERRORS_RO)) {
 799                 if (def_errors == EXT4_ERRORS_PANIC ||
 800                     def_errors == EXT4_ERRORS_CONTINUE) {
 801                         seq_puts(seq, ",errors=remount-ro");
 802                 }
 803         }
 804         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 805                 seq_puts(seq, ",errors=continue");
 806         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 807                 seq_puts(seq, ",errors=panic");
 808         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 809                 seq_puts(seq, ",nouid32");
 810         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 811                 seq_puts(seq, ",debug");
 812         if (test_opt(sb, OLDALLOC))
 813                 seq_puts(seq, ",oldalloc");
 814 #ifdef CONFIG_EXT4_FS_XATTR
 815         if (test_opt(sb, XATTR_USER) &&
 816                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 817                 seq_puts(seq, ",user_xattr");
 818         if (!test_opt(sb, XATTR_USER) &&
 819             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 820                 seq_puts(seq, ",nouser_xattr");
 821         }
 822 #endif
 823 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 824         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 825                 seq_puts(seq, ",acl");
 826         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 827                 seq_puts(seq, ",noacl");
 828 #endif
 829         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 830                 seq_printf(seq, ",commit=%u",
 831                            (unsigned) (sbi->s_commit_interval / HZ));
 832         }
 833         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 834                 seq_printf(seq, ",min_batch_time=%u",
 835                            (unsigned) sbi->s_min_batch_time);
 836         }
 837         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 838                 seq_printf(seq, ",max_batch_time=%u",
 839                            (unsigned) sbi->s_min_batch_time);
 840         }
 841
 842         /*
 843          * We're changing the default of barrier mount option, so
 844          * let's always display its mount state so it's clear what its
 845          * status is.
 846          */
 847         seq_puts(seq, ",barrier=");
 848         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 849         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 850                 seq_puts(seq, ",journal_async_commit");
 851         if (test_opt(sb, NOBH))
 852                 seq_puts(seq, ",nobh");
 853         if (test_opt(sb, I_VERSION))
 854                 seq_puts(seq, ",i_version");
 855         if (!test_opt(sb, DELALLOC))
 856                 seq_puts(seq, ",nodelalloc");
 857
 858
 859         if (sbi->s_stripe)
 860                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 861         /*
 862          * journal mode get enabled in different ways
 863          * So just print the value even if we didn't specify it
 864          */
 865         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 866                 seq_puts(seq, ",data=journal");
 867         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 868                 seq_puts(seq, ",data=ordered");
 869         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 870                 seq_puts(seq, ",data=writeback");
 871
 872         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 873                 seq_printf(seq, ",inode_readahead_blks=%u",
 874                            sbi->s_inode_readahead_blks);
 875
 876         if (test_opt(sb, DATA_ERR_ABORT))
 877                 seq_puts(seq, ",data_err=abort");
 878
 879         if (test_opt(sb, NO_AUTO_DA_ALLOC))
 880                 seq_puts(seq, ",noauto_da_alloc");
 881
 882         ext4_show_quota_options(seq, sb);
 883
 884         return 0;
 885 }
 886
 887 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 888                                         u64 ino, u32 generation)
 889 {
 890         struct inode *inode;
 891
 892         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 893                 return ERR_PTR(-ESTALE);
 894         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 895                 return ERR_PTR(-ESTALE);
 896
 897         /* iget isn't really right if the inode is currently unallocated!!
 898          *
 899          * ext4_read_inode will return a bad_inode if the inode had been
 900          * deleted, so we should be safe.
 901          *
 902          * Currently we don't know the generation for parent directory, so
 903          * a generation of 0 means "accept any"
 904          */
 905         inode = ext4_iget(sb, ino);
 906         if (IS_ERR(inode))
 907                 return ERR_CAST(inode);
 908         if (generation && inode->i_generation != generation) {
 909                 iput(inode);
 910                 return ERR_PTR(-ESTALE);
 911         }
 912
 913         return inode;
 914 }
 915
 916 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 917                                         int fh_len, int fh_type)
 918 {
 919         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 920                                     ext4_nfs_get_inode);
 921 }
 922
 923 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 924                                         int fh_len, int fh_type)
 925 {
 926         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 927                                     ext4_nfs_get_inode);
 928 }
 929
 930 /*
 931  * Try to release metadata pages (indirect blocks, directories) which are
 932  * mapped via the block device.  Since these pages could have journal heads
 933  * which would prevent try_to_free_buffers() from freeing them, we must use
 934  * jbd2 layer's try_to_free_buffers() function to release them.
 935  */
 936 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 937                                  gfp_t wait)
 938 {
 939         journal_t *journal = EXT4_SB(sb)->s_journal;
 940
 941         WARN_ON(PageChecked(page));
 942         if (!page_has_buffers(page))
 943                 return 0;
 944         if (journal)
 945                 return jbd2_journal_try_to_free_buffers(journal, page,
 946                                                         wait & ~__GFP_WAIT);
 947         return try_to_free_buffers(page);
 948 }
 949
 950 #ifdef CONFIG_QUOTA
 951 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 952 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 953
 954 static int ext4_write_dquot(struct dquot *dquot);
 955 static int ext4_acquire_dquot(struct dquot *dquot);
 956 static int ext4_release_dquot(struct dquot *dquot);
 957 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 958 static int ext4_write_info(struct super_block *sb, int type);
 959 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 960                                 char *path, int remount);
 961 static int ext4_quota_on_mount(struct super_block *sb, int type);
 962 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 963                                size_t len, loff_t off);
 964 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 965                                 const char *data, size_t len, loff_t off);
 966
 967 static struct dquot_operations ext4_quota_operations = {
 968         .initialize     = dquot_initialize,
 969         .drop           = dquot_drop,
 970         .alloc_space    = dquot_alloc_space,
 971         .reserve_space  = dquot_reserve_space,
 972         .claim_space    = dquot_claim_space,
 973         .release_rsv    = dquot_release_reserved_space,
 974         .get_reserved_space = ext4_get_reserved_space,
 975         .alloc_inode    = dquot_alloc_inode,
 976         .free_space     = dquot_free_space,
 977         .free_inode     = dquot_free_inode,
 978         .transfer       = dquot_transfer,
 979         .write_dquot    = ext4_write_dquot,
 980         .acquire_dquot  = ext4_acquire_dquot,
 981         .release_dquot  = ext4_release_dquot,
 982         .mark_dirty     = ext4_mark_dquot_dirty,
 983         .write_info     = ext4_write_info,
 984         .alloc_dquot    = dquot_alloc,
 985         .destroy_dquot  = dquot_destroy,
 986 };
 987
 988 static struct quotactl_ops ext4_qctl_operations = {
 989         .quota_on       = ext4_quota_on,
 990         .quota_off      = vfs_quota_off,
 991         .quota_sync     = vfs_quota_sync,
 992         .get_info       = vfs_get_dqinfo,
 993         .set_info       = vfs_set_dqinfo,
 994         .get_dqblk      = vfs_get_dqblk,
 995         .set_dqblk      = vfs_set_dqblk
 996 };
 997 #endif
 998
 999 static const struct super_operations ext4_sops = {
1000         .alloc_inode    = ext4_alloc_inode,
1001         .destroy_inode  = ext4_destroy_inode,
1002         .write_inode    = ext4_write_inode,
1003         .dirty_inode    = ext4_dirty_inode,
1004         .delete_inode   = ext4_delete_inode,
1005         .put_super      = ext4_put_super,
1006         .sync_fs        = ext4_sync_fs,
1007         .freeze_fs      = ext4_freeze,
1008         .unfreeze_fs    = ext4_unfreeze,
1009         .statfs         = ext4_statfs,
1010         .remount_fs     = ext4_remount,
1011         .clear_inode    = ext4_clear_inode,
1012         .show_options   = ext4_show_options,
1013 #ifdef CONFIG_QUOTA
1014         .quota_read     = ext4_quota_read,
1015         .quota_write    = ext4_quota_write,
1016 #endif
1017         .bdev_try_to_free_page = bdev_try_to_free_page,
1018 };
1019
1020 static const struct super_operations ext4_nojournal_sops = {
1021         .alloc_inode    = ext4_alloc_inode,
1022         .destroy_inode  = ext4_destroy_inode,
1023         .write_inode    = ext4_write_inode,
1024         .dirty_inode    = ext4_dirty_inode,
1025         .delete_inode   = ext4_delete_inode,
1026         .write_super    = ext4_write_super,
1027         .put_super      = ext4_put_super,
1028         .statfs         = ext4_statfs,
1029         .remount_fs     = ext4_remount,
1030         .clear_inode    = ext4_clear_inode,
1031         .show_options   = ext4_show_options,
1032 #ifdef CONFIG_QUOTA
1033         .quota_read     = ext4_quota_read,
1034         .quota_write    = ext4_quota_write,
1035 #endif
1036         .bdev_try_to_free_page = bdev_try_to_free_page,
1037 };
1038
1039 static const struct export_operations ext4_export_ops = {
1040         .fh_to_dentry = ext4_fh_to_dentry,
1041         .fh_to_parent = ext4_fh_to_parent,
1042         .get_parent = ext4_get_parent,
1043 };
1044
1045 enum {
1046         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1047         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1048         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1049         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1050         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1051         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1052         Opt_journal_update, Opt_journal_dev,
1053         Opt_journal_checksum, Opt_journal_async_commit,
1054         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1055         Opt_data_err_abort, Opt_data_err_ignore, Opt_mb_history_length,
1056         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1057         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
1058         Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err, Opt_resize,
1059         Opt_usrquota, Opt_grpquota, Opt_i_version,
1060         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1061         Opt_block_validity, Opt_noblock_validity,
1062         Opt_inode_readahead_blks, Opt_journal_ioprio
1063 };
1064
1065 static const match_table_t tokens = {
1066         {Opt_bsd_df, "bsddf"},
1067         {Opt_minix_df, "minixdf"},
1068         {Opt_grpid, "grpid"},
1069         {Opt_grpid, "bsdgroups"},
1070         {Opt_nogrpid, "nogrpid"},
1071         {Opt_nogrpid, "sysvgroups"},
1072         {Opt_resgid, "resgid=%u"},
1073         {Opt_resuid, "resuid=%u"},
1074         {Opt_sb, "sb=%u"},
1075         {Opt_err_cont, "errors=continue"},
1076         {Opt_err_panic, "errors=panic"},
1077         {Opt_err_ro, "errors=remount-ro"},
1078         {Opt_nouid32, "nouid32"},
1079         {Opt_debug, "debug"},
1080         {Opt_oldalloc, "oldalloc"},
1081         {Opt_orlov, "orlov"},
1082         {Opt_user_xattr, "user_xattr"},
1083         {Opt_nouser_xattr, "nouser_xattr"},
1084         {Opt_acl, "acl"},
1085         {Opt_noacl, "noacl"},
1086         {Opt_noload, "noload"},
1087         {Opt_nobh, "nobh"},
1088         {Opt_bh, "bh"},
1089         {Opt_commit, "commit=%u"},
1090         {Opt_min_batch_time, "min_batch_time=%u"},
1091         {Opt_max_batch_time, "max_batch_time=%u"},
1092         {Opt_journal_update, "journal=update"},
1093         {Opt_journal_dev, "journal_dev=%u"},
1094         {Opt_journal_checksum, "journal_checksum"},
1095         {Opt_journal_async_commit, "journal_async_commit"},
1096         {Opt_abort, "abort"},
1097         {Opt_data_journal, "data=journal"},
1098         {Opt_data_ordered, "data=ordered"},
1099         {Opt_data_writeback, "data=writeback"},
1100         {Opt_data_err_abort, "data_err=abort"},
1101         {Opt_data_err_ignore, "data_err=ignore"},
1102         {Opt_mb_history_length, "mb_history_length=%u"},
1103         {Opt_offusrjquota, "usrjquota="},
1104         {Opt_usrjquota, "usrjquota=%s"},
1105         {Opt_offgrpjquota, "grpjquota="},
1106         {Opt_grpjquota, "grpjquota=%s"},
1107         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1108         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1109         {Opt_grpquota, "grpquota"},
1110         {Opt_noquota, "noquota"},
1111         {Opt_quota, "quota"},
1112         {Opt_usrquota, "usrquota"},
1113         {Opt_barrier, "barrier=%u"},
1114         {Opt_barrier, "barrier"},
1115         {Opt_nobarrier, "nobarrier"},
1116         {Opt_i_version, "i_version"},
1117         {Opt_stripe, "stripe=%u"},
1118         {Opt_resize, "resize"},
1119         {Opt_delalloc, "delalloc"},
1120         {Opt_nodelalloc, "nodelalloc"},
1121         {Opt_block_validity, "block_validity"},
1122         {Opt_noblock_validity, "noblock_validity"},
1123         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1124         {Opt_journal_ioprio, "journal_ioprio=%u"},
1125         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1126         {Opt_auto_da_alloc, "auto_da_alloc"},
1127         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1128         {Opt_err, NULL},
1129 };
1130
1131 static ext4_fsblk_t get_sb_block(void **data)
1132 {
1133         ext4_fsblk_t    sb_block;
1134         char            *options = (char *) *data;
1135
1136         if (!options || strncmp(options, "sb=", 3) != 0)
1137                 return 1;       /* Default location */
1138
1139         options += 3;
1140         /* TODO: use simple_strtoll with >32bit ext4 */
1141         sb_block = simple_strtoul(options, &options, 0);
1142         if (*options && *options != ',') {
1143                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1144                        (char *) *data);
1145                 return 1;
1146         }
1147         if (*options == ',')
1148                 options++;
1149         *data = (void *) options;
1150
1151         return sb_block;
1152 }
1153
1154 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1155
1156 static int parse_options(char *options, struct super_block *sb,
1157                          unsigned long *journal_devnum,
1158                          unsigned int *journal_ioprio,
1159                          ext4_fsblk_t *n_blocks_count, int is_remount)
1160 {
1161         struct ext4_sb_info *sbi = EXT4_SB(sb);
1162         char *p;
1163         substring_t args[MAX_OPT_ARGS];
1164         int data_opt = 0;
1165         int option;
1166 #ifdef CONFIG_QUOTA
1167         int qtype, qfmt;
1168         char *qname;
1169 #endif
1170
1171         if (!options)
1172                 return 1;
1173
1174         while ((p = strsep(&options, ",")) != NULL) {
1175                 int token;
1176                 if (!*p)
1177                         continue;
1178
1179                 token = match_token(p, tokens, args);
1180                 switch (token) {
1181                 case Opt_bsd_df:
1182                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1183                         break;
1184                 case Opt_minix_df:
1185                         set_opt(sbi->s_mount_opt, MINIX_DF);
1186                         break;
1187                 case Opt_grpid:
1188                         set_opt(sbi->s_mount_opt, GRPID);
1189                         break;
1190                 case Opt_nogrpid:
1191                         clear_opt(sbi->s_mount_opt, GRPID);
1192                         break;
1193                 case Opt_resuid:
1194                         if (match_int(&args[0], &option))
1195                                 return 0;
1196                         sbi->s_resuid = option;
1197                         break;
1198                 case Opt_resgid:
1199                         if (match_int(&args[0], &option))
1200                                 return 0;
1201                         sbi->s_resgid = option;
1202                         break;
1203                 case Opt_sb:
1204                         /* handled by get_sb_block() instead of here */
1205                         /* *sb_block = match_int(&args[0]); */
1206                         break;
1207                 case Opt_err_panic:
1208                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1209                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1210                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1211                         break;
1212                 case Opt_err_ro:
1213                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1214                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1215                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1216                         break;
1217                 case Opt_err_cont:
1218                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1219                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1220                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1221                         break;
1222                 case Opt_nouid32:
1223                         set_opt(sbi->s_mount_opt, NO_UID32);
1224                         break;
1225                 case Opt_debug:
1226                         set_opt(sbi->s_mount_opt, DEBUG);
1227                         break;
1228                 case Opt_oldalloc:
1229                         set_opt(sbi->s_mount_opt, OLDALLOC);
1230                         break;
1231                 case Opt_orlov:
1232                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1233                         break;
1234 #ifdef CONFIG_EXT4_FS_XATTR
1235                 case Opt_user_xattr:
1236                         set_opt(sbi->s_mount_opt, XATTR_USER);
1237                         break;
1238                 case Opt_nouser_xattr:
1239                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1240                         break;
1241 #else
1242                 case Opt_user_xattr:
1243                 case Opt_nouser_xattr:
1244                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1245                         break;
1246 #endif
1247 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1248                 case Opt_acl:
1249                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1250                         break;
1251                 case Opt_noacl:
1252                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1253                         break;
1254 #else
1255                 case Opt_acl:
1256                 case Opt_noacl:
1257                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1258                         break;
1259 #endif
1260                 case Opt_journal_update:
1261                         /* @@@ FIXME */
1262                         /* Eventually we will want to be able to create
1263                            a journal file here.  For now, only allow the
1264                            user to specify an existing inode to be the
1265                            journal file. */
1266                         if (is_remount) {
1267                                 ext4_msg(sb, KERN_ERR,
1268                                          "Cannot specify journal on remount");
1269                                 return 0;
1270                         }
1271                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1272                         break;
1273                 case Opt_journal_dev:
1274                         if (is_remount) {
1275                                 ext4_msg(sb, KERN_ERR,
1276                                         "Cannot specify journal on remount");
1277                                 return 0;
1278                         }
1279                         if (match_int(&args[0], &option))
1280                                 return 0;
1281                         *journal_devnum = option;
1282                         break;
1283                 case Opt_journal_checksum:
1284                         break;  /* Kept for backwards compatibility */
1285                 case Opt_journal_async_commit:
1286                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1287                         break;
1288                 case Opt_noload:
1289                         set_opt(sbi->s_mount_opt, NOLOAD);
1290                         break;
1291                 case Opt_commit:
1292                         if (match_int(&args[0], &option))
1293                                 return 0;
1294                         if (option < 0)
1295                                 return 0;
1296                         if (option == 0)
1297                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1298                         sbi->s_commit_interval = HZ * option;
1299                         break;
1300                 case Opt_max_batch_time:
1301                         if (match_int(&args[0], &option))
1302                                 return 0;
1303                         if (option < 0)
1304                                 return 0;
1305                         if (option == 0)
1306                                 option = EXT4_DEF_MAX_BATCH_TIME;
1307                         sbi->s_max_batch_time = option;
1308                         break;
1309                 case Opt_min_batch_time:
1310                         if (match_int(&args[0], &option))
1311                                 return 0;
1312                         if (option < 0)
1313                                 return 0;
1314                         sbi->s_min_batch_time = option;
1315                         break;
1316                 case Opt_data_journal:
1317                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1318                         goto datacheck;
1319                 case Opt_data_ordered:
1320                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1321                         goto datacheck;
1322                 case Opt_data_writeback:
1323                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1324                 datacheck:
1325                         if (is_remount) {
1326                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1327                                                 != data_opt) {
1328                                         ext4_msg(sb, KERN_ERR,
1329                                                 "Cannot change data mode on remount");
1330                                         return 0;
1331                                 }
1332                         } else {
1333                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1334                                 sbi->s_mount_opt |= data_opt;
1335                         }
1336                         break;
1337                 case Opt_data_err_abort:
1338                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1339                         break;
1340                 case Opt_data_err_ignore:
1341                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1342                         break;
1343                 case Opt_mb_history_length:
1344                         if (match_int(&args[0], &option))
1345                                 return 0;
1346                         if (option < 0)
1347                                 return 0;
1348                         sbi->s_mb_history_max = option;
1349                         break;
1350 #ifdef CONFIG_QUOTA
1351                 case Opt_usrjquota:
1352                         qtype = USRQUOTA;
1353                         goto set_qf_name;
1354                 case Opt_grpjquota:
1355                         qtype = GRPQUOTA;
1356 set_qf_name:
1357                         if (sb_any_quota_loaded(sb) &&
1358                             !sbi->s_qf_names[qtype]) {
1359                                 ext4_msg(sb, KERN_ERR,
1360                                        "Cannot change journaled "
1361                                        "quota options when quota turned on");
1362                                 return 0;
1363                         }
1364                         qname = match_strdup(&args[0]);
1365                         if (!qname) {
1366                                 ext4_msg(sb, KERN_ERR,
1367                                         "Not enough memory for "
1368                                         "storing quotafile name");
1369                                 return 0;
1370                         }
1371                         if (sbi->s_qf_names[qtype] &&
1372                             strcmp(sbi->s_qf_names[qtype], qname)) {
1373                                 ext4_msg(sb, KERN_ERR,
1374                                         "%s quota file already "
1375                                         "specified", QTYPE2NAME(qtype));
1376                                 kfree(qname);
1377                                 return 0;
1378                         }
1379                         sbi->s_qf_names[qtype] = qname;
1380                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1381                                 ext4_msg(sb, KERN_ERR,
1382                                         "quotafile must be on "
1383                                         "filesystem root");
1384                                 kfree(sbi->s_qf_names[qtype]);
1385                                 sbi->s_qf_names[qtype] = NULL;
1386                                 return 0;
1387                         }
1388                         set_opt(sbi->s_mount_opt, QUOTA);
1389                         break;
1390                 case Opt_offusrjquota:
1391                         qtype = USRQUOTA;
1392                         goto clear_qf_name;
1393                 case Opt_offgrpjquota:
1394                         qtype = GRPQUOTA;
1395 clear_qf_name:
1396                         if (sb_any_quota_loaded(sb) &&
1397                             sbi->s_qf_names[qtype]) {
1398                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1399                                         "journaled quota options when "
1400                                         "quota turned on");
1401                                 return 0;
1402                         }
1403                         /*
1404                          * The space will be released later when all options
1405                          * are confirmed to be correct
1406                          */
1407                         sbi->s_qf_names[qtype] = NULL;
1408                         break;
1409                 case Opt_jqfmt_vfsold:
1410                         qfmt = QFMT_VFS_OLD;
1411                         goto set_qf_format;
1412                 case Opt_jqfmt_vfsv0:
1413                         qfmt = QFMT_VFS_V0;
1414 set_qf_format:
1415                         if (sb_any_quota_loaded(sb) &&
1416                             sbi->s_jquota_fmt != qfmt) {
1417                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1418                                         "journaled quota options when "
1419                                         "quota turned on");
1420                                 return 0;
1421                         }
1422                         sbi->s_jquota_fmt = qfmt;
1423                         break;
1424                 case Opt_quota:
1425                 case Opt_usrquota:
1426                         set_opt(sbi->s_mount_opt, QUOTA);
1427                         set_opt(sbi->s_mount_opt, USRQUOTA);
1428                         break;
1429                 case Opt_grpquota:
1430                         set_opt(sbi->s_mount_opt, QUOTA);
1431                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1432                         break;
1433                 case Opt_noquota:
1434                         if (sb_any_quota_loaded(sb)) {
1435                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1436                                         "options when quota turned on");
1437                                 return 0;
1438                         }
1439                         clear_opt(sbi->s_mount_opt, QUOTA);
1440                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1441                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1442                         break;
1443 #else
1444                 case Opt_quota:
1445                 case Opt_usrquota:
1446                 case Opt_grpquota:
1447                         ext4_msg(sb, KERN_ERR,
1448                                 "quota options not supported");
1449                         break;
1450                 case Opt_usrjquota:
1451                 case Opt_grpjquota:
1452                 case Opt_offusrjquota:
1453                 case Opt_offgrpjquota:
1454                 case Opt_jqfmt_vfsold:
1455                 case Opt_jqfmt_vfsv0:
1456                         ext4_msg(sb, KERN_ERR,
1457                                 "journaled quota options not supported");
1458                         break;
1459                 case Opt_noquota:
1460                         break;
1461 #endif
1462                 case Opt_abort:
1463                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1464                         break;
1465                 case Opt_nobarrier:
1466                         clear_opt(sbi->s_mount_opt, BARRIER);
1467                         break;
1468                 case Opt_barrier:
1469                         if (match_int(&args[0], &option)) {
1470                                 set_opt(sbi->s_mount_opt, BARRIER);
1471                                 break;
1472                         }
1473                         if (option)
1474                                 set_opt(sbi->s_mount_opt, BARRIER);
1475                         else
1476                                 clear_opt(sbi->s_mount_opt, BARRIER);
1477                         break;
1478                 case Opt_ignore:
1479                         break;
1480                 case Opt_resize:
1481                         if (!is_remount) {
1482                                 ext4_msg(sb, KERN_ERR,
1483                                         "resize option only available "
1484                                         "for remount");
1485                                 return 0;
1486                         }
1487                         if (match_int(&args[0], &option) != 0)
1488                                 return 0;
1489                         *n_blocks_count = option;
1490                         break;
1491                 case Opt_nobh:
1492                         set_opt(sbi->s_mount_opt, NOBH);
1493                         break;
1494                 case Opt_bh:
1495                         clear_opt(sbi->s_mount_opt, NOBH);
1496                         break;
1497                 case Opt_i_version:
1498                         set_opt(sbi->s_mount_opt, I_VERSION);
1499                         sb->s_flags |= MS_I_VERSION;
1500                         break;
1501                 case Opt_nodelalloc:
1502                         clear_opt(sbi->s_mount_opt, DELALLOC);
1503                         break;
1504                 case Opt_stripe:
1505                         if (match_int(&args[0], &option))
1506                                 return 0;
1507                         if (option < 0)
1508                                 return 0;
1509                         sbi->s_stripe = option;
1510                         break;
1511                 case Opt_delalloc:
1512                         set_opt(sbi->s_mount_opt, DELALLOC);
1513                         break;
1514                 case Opt_block_validity:
1515                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1516                         break;
1517                 case Opt_noblock_validity:
1518                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1519                         break;
1520                 case Opt_inode_readahead_blks:
1521                         if (match_int(&args[0], &option))
1522                                 return 0;
1523                         if (option < 0 || option > (1 << 30))
1524                                 return 0;
1525                         if (!is_power_of_2(option)) {
1526                                 ext4_msg(sb, KERN_ERR,
1527                                          "EXT4-fs: inode_readahead_blks"
1528                                          " must be a power of 2");
1529                                 return 0;
1530                         }
1531                         sbi->s_inode_readahead_blks = option;
1532                         break;
1533                 case Opt_journal_ioprio:
1534                         if (match_int(&args[0], &option))
1535                                 return 0;
1536                         if (option < 0 || option > 7)
1537                                 break;
1538                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1539                                                             option);
1540                         break;
1541                 case Opt_noauto_da_alloc:
1542                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1543                         break;
1544                 case Opt_auto_da_alloc:
1545                         if (match_int(&args[0], &option)) {
1546                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1547                                 break;
1548                         }
1549                         if (option)
1550                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1551                         else
1552                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1553                         break;
1554                 default:
1555                         ext4_msg(sb, KERN_ERR,
1556                                "Unrecognized mount option \"%s\" "
1557                                "or missing value", p);
1558                         return 0;
1559                 }
1560         }
1561 #ifdef CONFIG_QUOTA
1562         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1563                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1564                      sbi->s_qf_names[USRQUOTA])
1565                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1566
1567                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1568                      sbi->s_qf_names[GRPQUOTA])
1569                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1570
1571                 if ((sbi->s_qf_names[USRQUOTA] &&
1572                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1573                     (sbi->s_qf_names[GRPQUOTA] &&
1574                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1575                         ext4_msg(sb, KERN_ERR, "old and new quota "
1576                                         "format mixing");
1577                         return 0;
1578                 }
1579
1580                 if (!sbi->s_jquota_fmt) {
1581                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1582                                         "not specified");
1583                         return 0;
1584                 }
1585         } else {
1586                 if (sbi->s_jquota_fmt) {
1587                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1588                                         "specified with no journaling "
1589                                         "enabled");
1590                         return 0;
1591                 }
1592         }
1593 #endif
1594         return 1;
1595 }
1596
1597 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1598                             int read_only)
1599 {
1600         struct ext4_sb_info *sbi = EXT4_SB(sb);
1601         int res = 0;
1602
1603         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1604                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1605                          "forcing read-only mode");
1606                 res = MS_RDONLY;
1607         }
1608         if (read_only)
1609                 return res;
1610         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1611                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1612                          "running e2fsck is recommended");
1613         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1614                 ext4_msg(sb, KERN_WARNING,
1615                          "warning: mounting fs with errors, "
1616                          "running e2fsck is recommended");
1617         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1618                  le16_to_cpu(es->s_mnt_count) >=
1619                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1620                 ext4_msg(sb, KERN_WARNING,
1621                          "warning: maximal mount count reached, "
1622                          "running e2fsck is recommended");
1623         else if (le32_to_cpu(es->s_checkinterval) &&
1624                 (le32_to_cpu(es->s_lastcheck) +
1625                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1626                 ext4_msg(sb, KERN_WARNING,
1627                          "warning: checktime reached, "
1628                          "running e2fsck is recommended");
1629         if (!sbi->s_journal)
1630                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1631         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1632                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1633         le16_add_cpu(&es->s_mnt_count, 1);
1634         es->s_mtime = cpu_to_le32(get_seconds());
1635         ext4_update_dynamic_rev(sb);
1636         if (sbi->s_journal)
1637                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1638
1639         ext4_commit_super(sb, 1);
1640         if (test_opt(sb, DEBUG))
1641                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1642                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1643                         sb->s_blocksize,
1644                         sbi->s_groups_count,
1645                         EXT4_BLOCKS_PER_GROUP(sb),
1646                         EXT4_INODES_PER_GROUP(sb),
1647                         sbi->s_mount_opt);
1648
1649         if (EXT4_SB(sb)->s_journal) {
1650                 ext4_msg(sb, KERN_INFO, "%s journal on %s",
1651                        EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1652                        "external", EXT4_SB(sb)->s_journal->j_devname);
1653         } else {
1654                 ext4_msg(sb, KERN_INFO, "no journal");
1655         }
1656         return res;
1657 }
1658
1659 static int ext4_fill_flex_info(struct super_block *sb)
1660 {
1661         struct ext4_sb_info *sbi = EXT4_SB(sb);
1662         struct ext4_group_desc *gdp = NULL;
1663         ext4_group_t flex_group_count;
1664         ext4_group_t flex_group;
1665         int groups_per_flex = 0;
1666         size_t size;
1667         int i;
1668
1669         if (!sbi->s_es->s_log_groups_per_flex) {
1670                 sbi->s_log_groups_per_flex = 0;
1671                 return 1;
1672         }
1673
1674         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1675         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1676
1677         /* We allocate both existing and potentially added groups */
1678         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1679                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1680                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1681         size = flex_group_count * sizeof(struct flex_groups);
1682         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1683         if (sbi->s_flex_groups == NULL) {
1684                 sbi->s_flex_groups = vmalloc(size);
1685                 if (sbi->s_flex_groups)
1686                         memset(sbi->s_flex_groups, 0, size);
1687         }
1688         if (sbi->s_flex_groups == NULL) {
1689                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1690                                 "%u flex groups", flex_group_count);
1691                 goto failed;
1692         }
1693
1694         for (i = 0; i < sbi->s_groups_count; i++) {
1695                 gdp = ext4_get_group_desc(sb, i, NULL);
1696
1697                 flex_group = ext4_flex_group(sbi, i);
1698                 atomic_add(ext4_free_inodes_count(sb, gdp),
1699                            &sbi->s_flex_groups[flex_group].free_inodes);
1700                 atomic_add(ext4_free_blks_count(sb, gdp),
1701                            &sbi->s_flex_groups[flex_group].free_blocks);
1702                 atomic_add(ext4_used_dirs_count(sb, gdp),
1703                            &sbi->s_flex_groups[flex_group].used_dirs);
1704         }
1705
1706         return 1;
1707 failed:
1708         return 0;
1709 }
1710
1711 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1712                             struct ext4_group_desc *gdp)
1713 {
1714         __u16 crc = 0;
1715
1716         if (sbi->s_es->s_feature_ro_compat &
1717             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1718                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1719                 __le32 le_group = cpu_to_le32(block_group);
1720
1721                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1722                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1723                 crc = crc16(crc, (__u8 *)gdp, offset);
1724                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1725                 /* for checksum of struct ext4_group_desc do the rest...*/
1726                 if ((sbi->s_es->s_feature_incompat &
1727                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1728                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1729                         crc = crc16(crc, (__u8 *)gdp + offset,
1730                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1731                                         offset);
1732         }
1733
1734         return cpu_to_le16(crc);
1735 }
1736
1737 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1738                                 struct ext4_group_desc *gdp)
1739 {
1740         if ((sbi->s_es->s_feature_ro_compat &
1741              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1742             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1743                 return 0;
1744
1745         return 1;
1746 }
1747
1748 /* Called at mount-time, super-block is locked */
1749 static int ext4_check_descriptors(struct super_block *sb)
1750 {
1751         struct ext4_sb_info *sbi = EXT4_SB(sb);
1752         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1753         ext4_fsblk_t last_block;
1754         ext4_fsblk_t block_bitmap;
1755         ext4_fsblk_t inode_bitmap;
1756         ext4_fsblk_t inode_table;
1757         int flexbg_flag = 0;
1758         ext4_group_t i;
1759
1760         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1761                 flexbg_flag = 1;
1762
1763         ext4_debug("Checking group descriptors");
1764
1765         for (i = 0; i < sbi->s_groups_count; i++) {
1766                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1767
1768                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1769                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1770                 else
1771                         last_block = first_block +
1772                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1773
1774                 block_bitmap = ext4_block_bitmap(sb, gdp);
1775                 if (block_bitmap < first_block || block_bitmap > last_block) {
1776                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1777                                "Block bitmap for group %u not in group "
1778                                "(block %llu)!", i, block_bitmap);
1779                         return 0;
1780                 }
1781                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1782                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1783                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1784                                "Inode bitmap for group %u not in group "
1785                                "(block %llu)!", i, inode_bitmap);
1786                         return 0;
1787                 }
1788                 inode_table = ext4_inode_table(sb, gdp);
1789                 if (inode_table < first_block ||
1790                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1791                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1792                                "Inode table for group %u not in group "
1793                                "(block %llu)!", i, inode_table);
1794                         return 0;
1795                 }
1796                 ext4_lock_group(sb, i);
1797                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1798                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1799                                  "Checksum for group %u failed (%u!=%u)",
1800                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1801                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1802                         if (!(sb->s_flags & MS_RDONLY)) {
1803                                 ext4_unlock_group(sb, i);
1804                                 return 0;
1805                         }
1806                 }
1807                 ext4_unlock_group(sb, i);
1808                 if (!flexbg_flag)
1809                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1810         }
1811
1812         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1813         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1814         return 1;
1815 }
1816
1817 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1818  * the superblock) which were deleted from all directories, but held open by
1819  * a process at the time of a crash.  We walk the list and try to delete these
1820  * inodes at recovery time (only with a read-write filesystem).
1821  *
1822  * In order to keep the orphan inode chain consistent during traversal (in
1823  * case of crash during recovery), we link each inode into the superblock
1824  * orphan list_head and handle it the same way as an inode deletion during
1825  * normal operation (which journals the operations for us).
1826  *
1827  * We only do an iget() and an iput() on each inode, which is very safe if we
1828  * accidentally point at an in-use or already deleted inode.  The worst that
1829  * can happen in this case is that we get a "bit already cleared" message from
1830  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1831  * e2fsck was run on this filesystem, and it must have already done the orphan
1832  * inode cleanup for us, so we can safely abort without any further action.
1833  */
1834 static void ext4_orphan_cleanup(struct super_block *sb,
1835                                 struct ext4_super_block *es)
1836 {
1837         unsigned int s_flags = sb->s_flags;
1838         int nr_orphans = 0, nr_truncates = 0;
1839 #ifdef CONFIG_QUOTA
1840         int i;
1841 #endif
1842         if (!es->s_last_orphan) {
1843                 jbd_debug(4, "no orphan inodes to clean up\n");
1844                 return;
1845         }
1846
1847         if (bdev_read_only(sb->s_bdev)) {
1848                 ext4_msg(sb, KERN_ERR, "write access "
1849                         "unavailable, skipping orphan cleanup");
1850                 return;
1851         }
1852
1853         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1854                 if (es->s_last_orphan)
1855                         jbd_debug(1, "Errors on filesystem, "
1856                                   "clearing orphan list.\n");
1857                 es->s_last_orphan = 0;
1858                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1859                 return;
1860         }
1861
1862         if (s_flags & MS_RDONLY) {
1863                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1864                 sb->s_flags &= ~MS_RDONLY;
1865         }
1866 #ifdef CONFIG_QUOTA
1867         /* Needed for iput() to work correctly and not trash data */
1868         sb->s_flags |= MS_ACTIVE;
1869         /* Turn on quotas so that they are updated correctly */
1870         for (i = 0; i < MAXQUOTAS; i++) {
1871                 if (EXT4_SB(sb)->s_qf_names[i]) {
1872                         int ret = ext4_quota_on_mount(sb, i);
1873                         if (ret < 0)
1874                                 ext4_msg(sb, KERN_ERR,
1875                                         "Cannot turn on journaled "
1876                                         "quota: error %d", ret);
1877                 }
1878         }
1879 #endif
1880
1881         while (es->s_last_orphan) {
1882                 struct inode *inode;
1883
1884                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1885                 if (IS_ERR(inode)) {
1886                         es->s_last_orphan = 0;
1887                         break;
1888                 }
1889
1890                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1891                 vfs_dq_init(inode);
1892                 if (inode->i_nlink) {
1893                         ext4_msg(sb, KERN_DEBUG,
1894                                 "%s: truncating inode %lu to %lld bytes",
1895                                 __func__, inode->i_ino, inode->i_size);
1896                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1897                                   inode->i_ino, inode->i_size);
1898                         ext4_truncate(inode);
1899                         nr_truncates++;
1900                 } else {
1901                         ext4_msg(sb, KERN_DEBUG,
1902                                 "%s: deleting unreferenced inode %lu",
1903                                 __func__, inode->i_ino);
1904                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1905                                   inode->i_ino);
1906                         nr_orphans++;
1907                 }
1908                 iput(inode);  /* The delete magic happens here! */
1909         }
1910
1911 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1912
1913         if (nr_orphans)
1914                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1915                        PLURAL(nr_orphans));
1916         if (nr_truncates)
1917                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1918                        PLURAL(nr_truncates));
1919 #ifdef CONFIG_QUOTA
1920         /* Turn quotas off */
1921         for (i = 0; i < MAXQUOTAS; i++) {
1922                 if (sb_dqopt(sb)->files[i])
1923                         vfs_quota_off(sb, i, 0);
1924         }
1925 #endif
1926         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1927 }
1928
1929 /*
1930  * Maximal extent format file size.
1931  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1932  * extent format containers, within a sector_t, and within i_blocks
1933  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1934  * so that won't be a limiting factor.
1935  *
1936  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1937  */
1938 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1939 {
1940         loff_t res;
1941         loff_t upper_limit = MAX_LFS_FILESIZE;
1942
1943         /* small i_blocks in vfs inode? */
1944         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1945                 /*
1946                  * CONFIG_LBDAF is not enabled implies the inode
1947                  * i_block represent total blocks in 512 bytes
1948                  * 32 == size of vfs inode i_blocks * 8
1949                  */
1950                 upper_limit = (1LL << 32) - 1;
1951
1952                 /* total blocks in file system block size */
1953                 upper_limit >>= (blkbits - 9);
1954                 upper_limit <<= blkbits;
1955         }
1956
1957         /* 32-bit extent-start container, ee_block */
1958         res = 1LL << 32;
1959         res <<= blkbits;
1960         res -= 1;
1961
1962         /* Sanity check against vm- & vfs- imposed limits */
1963         if (res > upper_limit)
1964                 res = upper_limit;
1965
1966         return res;
1967 }
1968
1969 /*
1970  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1971  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1972  * We need to be 1 filesystem block less than the 2^48 sector limit.
1973  */
1974 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
1975 {
1976         loff_t res = EXT4_NDIR_BLOCKS;
1977         int meta_blocks;
1978         loff_t upper_limit;
1979         /* This is calculated to be the largest file size for a dense, block
1980          * mapped file such that the file's total number of 512-byte sectors,
1981          * including data and all indirect blocks, does not exceed (2^48 - 1).
1982          *
1983          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
1984          * number of 512-byte sectors of the file.
1985          */
1986
1987         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1988                 /*
1989                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
1990                  * the inode i_block field represents total file blocks in
1991                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
1992                  */
1993                 upper_limit = (1LL << 32) - 1;
1994
1995                 /* total blocks in file system block size */
1996                 upper_limit >>= (bits - 9);
1997
1998         } else {
1999                 /*
2000                  * We use 48 bit ext4_inode i_blocks
2001                  * With EXT4_HUGE_FILE_FL set the i_blocks
2002                  * represent total number of blocks in
2003                  * file system block size
2004                  */
2005                 upper_limit = (1LL << 48) - 1;
2006
2007         }
2008
2009         /* indirect blocks */
2010         meta_blocks = 1;
2011         /* double indirect blocks */
2012         meta_blocks += 1 + (1LL << (bits-2));
2013         /* tripple indirect blocks */
2014         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2015
2016         upper_limit -= meta_blocks;
2017         upper_limit <<= bits;
2018
2019         res += 1LL << (bits-2);
2020         res += 1LL << (2*(bits-2));
2021         res += 1LL << (3*(bits-2));
2022         res <<= bits;
2023         if (res > upper_limit)
2024                 res = upper_limit;
2025
2026         if (res > MAX_LFS_FILESIZE)
2027                 res = MAX_LFS_FILESIZE;
2028
2029         return res;
2030 }
2031
2032 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2033                                    ext4_fsblk_t logical_sb_block, int nr)
2034 {
2035         struct ext4_sb_info *sbi = EXT4_SB(sb);
2036         ext4_group_t bg, first_meta_bg;
2037         int has_super = 0;
2038
2039         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2040
2041         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2042             nr < first_meta_bg)
2043                 return logical_sb_block + nr + 1;
2044         bg = sbi->s_desc_per_block * nr;
2045         if (ext4_bg_has_super(sb, bg))
2046                 has_super = 1;
2047
2048         return (has_super + ext4_group_first_block_no(sb, bg));
2049 }
2050
2051 /**
2052  * ext4_get_stripe_size: Get the stripe size.
2053  * @sbi: In memory super block info
2054  *
2055  * If we have specified it via mount option, then
2056  * use the mount option value. If the value specified at mount time is
2057  * greater than the blocks per group use the super block value.
2058  * If the super block value is greater than blocks per group return 0.
2059  * Allocator needs it be less than blocks per group.
2060  *
2061  */
2062 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2063 {
2064         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2065         unsigned long stripe_width =
2066                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2067
2068         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2069                 return sbi->s_stripe;
2070
2071         if (stripe_width <= sbi->s_blocks_per_group)
2072                 return stripe_width;
2073
2074         if (stride <= sbi->s_blocks_per_group)
2075                 return stride;
2076
2077         return 0;
2078 }
2079
2080 /* sysfs supprt */
2081
2082 struct ext4_attr {
2083         struct attribute attr;
2084         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2085         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2086                          const char *, size_t);
2087         int offset;
2088 };
2089
2090 static int parse_strtoul(const char *buf,
2091                 unsigned long max, unsigned long *value)
2092 {
2093         char *endp;
2094
2095         while (*buf && isspace(*buf))
2096                 buf++;
2097         *value = simple_strtoul(buf, &endp, 0);
2098         while (*endp && isspace(*endp))
2099                 endp++;
2100         if (*endp || *value > max)
2101                 return -EINVAL;
2102
2103         return 0;
2104 }
2105
2106 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2107                                               struct ext4_sb_info *sbi,
2108                                               char *buf)
2109 {
2110         return snprintf(buf, PAGE_SIZE, "%llu\n",
2111                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2112 }
2113
2114 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2115                                          struct ext4_sb_info *sbi, char *buf)
2116 {
2117         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2118
2119         return snprintf(buf, PAGE_SIZE, "%lu\n",
2120                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2121                          sbi->s_sectors_written_start) >> 1);
2122 }
2123
2124 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2125                                           struct ext4_sb_info *sbi, char *buf)
2126 {
2127         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2128
2129         return snprintf(buf, PAGE_SIZE, "%llu\n",
2130                         sbi->s_kbytes_written +
2131                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2132                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2133 }
2134
2135 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2136                                           struct ext4_sb_info *sbi,
2137                                           const char *buf, size_t count)
2138 {
2139         unsigned long t;
2140
2141         if (parse_strtoul(buf, 0x40000000, &t))
2142                 return -EINVAL;
2143
2144         if (!is_power_of_2(t))
2145                 return -EINVAL;
2146
2147         sbi->s_inode_readahead_blks = t;
2148         return count;
2149 }
2150
2151 static ssize_t sbi_ui_show(struct ext4_attr *a,
2152                            struct ext4_sb_info *sbi, char *buf)
2153 {
2154         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2155
2156         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2157 }
2158
2159 static ssize_t sbi_ui_store(struct ext4_attr *a,
2160                             struct ext4_sb_info *sbi,
2161                             const char *buf, size_t count)
2162 {
2163         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2164         unsigned long t;
2165
2166         if (parse_strtoul(buf, 0xffffffff, &t))
2167                 return -EINVAL;
2168         *ui = t;
2169         return count;
2170 }
2171
2172 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2173 static struct ext4_attr ext4_attr_##_name = {                   \
2174         .attr = {.name = __stringify(_name), .mode = _mode },   \
2175         .show   = _show,                                        \
2176         .store  = _store,                                       \
2177         .offset = offsetof(struct ext4_sb_info, _elname),       \
2178 }
2179 #define EXT4_ATTR(name, mode, show, store) \
2180 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2181
2182 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2183 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2184 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2185         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2186 #define ATTR_LIST(name) &ext4_attr_##name.attr
2187
2188 EXT4_RO_ATTR(delayed_allocation_blocks);
2189 EXT4_RO_ATTR(session_write_kbytes);
2190 EXT4_RO_ATTR(lifetime_write_kbytes);
2191 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2192                  inode_readahead_blks_store, s_inode_readahead_blks);
2193 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2194 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2195 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2196 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2197 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2198 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2199 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2200
2201 static struct attribute *ext4_attrs[] = {
2202         ATTR_LIST(delayed_allocation_blocks),
2203         ATTR_LIST(session_write_kbytes),
2204         ATTR_LIST(lifetime_write_kbytes),
2205         ATTR_LIST(inode_readahead_blks),
2206         ATTR_LIST(inode_goal),
2207         ATTR_LIST(mb_stats),
2208         ATTR_LIST(mb_max_to_scan),
2209         ATTR_LIST(mb_min_to_scan),
2210         ATTR_LIST(mb_order2_req),
2211         ATTR_LIST(mb_stream_req),
2212         ATTR_LIST(mb_group_prealloc),
2213         NULL,
2214 };
2215
2216 static ssize_t ext4_attr_show(struct kobject *kobj,
2217                               struct attribute *attr, char *buf)
2218 {
2219         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2220                                                 s_kobj);
2221         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2222
2223         return a->show ? a->show(a, sbi, buf) : 0;
2224 }
2225
2226 static ssize_t ext4_attr_store(struct kobject *kobj,
2227                                struct attribute *attr,
2228                                const char *buf, size_t len)
2229 {
2230         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2231                                                 s_kobj);
2232         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2233
2234         return a->store ? a->store(a, sbi, buf, len) : 0;
2235 }
2236
2237 static void ext4_sb_release(struct kobject *kobj)
2238 {
2239         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2240                                                 s_kobj);
2241         complete(&sbi->s_kobj_unregister);
2242 }
2243
2244
2245 static struct sysfs_ops ext4_attr_ops = {
2246         .show   = ext4_attr_show,
2247         .store  = ext4_attr_store,
2248 };
2249
2250 static struct kobj_type ext4_ktype = {
2251         .default_attrs  = ext4_attrs,
2252         .sysfs_ops      = &ext4_attr_ops,
2253         .release        = ext4_sb_release,
2254 };
2255
2256 /*
2257  * Check whether this filesystem can be mounted based on
2258  * the features present and the RDONLY/RDWR mount requested.
2259  * Returns 1 if this filesystem can be mounted as requested,
2260  * 0 if it cannot be.
2261  */
2262 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2263 {
2264         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2265                 ext4_msg(sb, KERN_ERR,
2266                         "Couldn't mount because of "
2267                         "unsupported optional features (%x)",
2268                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2269                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2270                 return 0;
2271         }
2272
2273         if (readonly)
2274                 return 1;
2275
2276         /* Check that feature set is OK for a read-write mount */
2277         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2278                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2279                          "unsupported optional features (%x)",
2280                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2281                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2282                 return 0;
2283         }
2284         /*
2285          * Large file size enabled file system can only be mounted
2286          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2287          */
2288         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2289                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2290                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2291                                  "cannot be mounted RDWR without "
2292                                  "CONFIG_LBDAF");
2293                         return 0;
2294                 }
2295         }
2296         return 1;
2297 }
2298
2299 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2300                                 __releases(kernel_lock)
2301                                 __acquires(kernel_lock)
2302 {
2303         struct buffer_head *bh;
2304         struct ext4_super_block *es = NULL;
2305         struct ext4_sb_info *sbi;
2306         ext4_fsblk_t block;
2307         ext4_fsblk_t sb_block = get_sb_block(&data);
2308         ext4_fsblk_t logical_sb_block;
2309         unsigned long offset = 0;
2310         unsigned long journal_devnum = 0;
2311         unsigned long def_mount_opts;
2312         struct inode *root;
2313         char *cp;
2314         const char *descr;
2315         int ret = -EINVAL;
2316         int blocksize;
2317         unsigned int db_count;
2318         unsigned int i;
2319         int needs_recovery, has_huge_files;
2320         __u64 blocks_count;
2321         int err;
2322         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2323
2324         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2325         if (!sbi)
2326                 return -ENOMEM;
2327
2328         sbi->s_blockgroup_lock =
2329                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2330         if (!sbi->s_blockgroup_lock) {
2331                 kfree(sbi);
2332                 return -ENOMEM;
2333         }
2334         sb->s_fs_info = sbi;
2335         sbi->s_mount_opt = 0;
2336         sbi->s_resuid = EXT4_DEF_RESUID;
2337         sbi->s_resgid = EXT4_DEF_RESGID;
2338         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2339         sbi->s_sb_block = sb_block;
2340         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2341                                                       sectors[1]);
2342
2343         unlock_kernel();
2344
2345         /* Cleanup superblock name */
2346         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2347                 *cp = '!';
2348
2349         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2350         if (!blocksize) {
2351                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2352                 goto out_fail;
2353         }
2354
2355         /*
2356          * The ext4 superblock will not be buffer aligned for other than 1kB
2357          * block sizes.  We need to calculate the offset from buffer start.
2358          */
2359         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2360                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2361                 offset = do_div(logical_sb_block, blocksize);
2362         } else {
2363                 logical_sb_block = sb_block;
2364         }
2365
2366         if (!(bh = sb_bread(sb, logical_sb_block))) {
2367                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2368                 goto out_fail;
2369         }
2370         /*
2371          * Note: s_es must be initialized as soon as possible because
2372          *       some ext4 macro-instructions depend on its value
2373          */
2374         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2375         sbi->s_es = es;
2376         sb->s_magic = le16_to_cpu(es->s_magic);
2377         if (sb->s_magic != EXT4_SUPER_MAGIC)
2378                 goto cantfind_ext4;
2379         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2380
2381         /* Set defaults before we parse the mount options */
2382         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2383         if (def_mount_opts & EXT4_DEFM_DEBUG)
2384                 set_opt(sbi->s_mount_opt, DEBUG);
2385         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2386                 set_opt(sbi->s_mount_opt, GRPID);
2387         if (def_mount_opts & EXT4_DEFM_UID16)
2388                 set_opt(sbi->s_mount_opt, NO_UID32);
2389 #ifdef CONFIG_EXT4_FS_XATTR
2390         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2391                 set_opt(sbi->s_mount_opt, XATTR_USER);
2392 #endif
2393 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2394         if (def_mount_opts & EXT4_DEFM_ACL)
2395                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2396 #endif
2397         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2398                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2399         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2400                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2401         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2402                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2403
2404         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2405                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2406         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2407                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2408         else
2409                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2410
2411         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2412         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2413         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2414         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2415         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2416         sbi->s_mb_history_max = default_mb_history_length;
2417
2418         set_opt(sbi->s_mount_opt, BARRIER);
2419
2420         /*
2421          * enable delayed allocation by default
2422          * Use -o nodelalloc to turn it off
2423          */
2424         set_opt(sbi->s_mount_opt, DELALLOC);
2425
2426         if (!parse_options((char *) data, sb, &journal_devnum,
2427                            &journal_ioprio, NULL, 0))
2428                 goto failed_mount;
2429
2430         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2431                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2432
2433         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2434             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2435              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2436              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2437                 ext4_msg(sb, KERN_WARNING,
2438                        "feature flags set on rev 0 fs, "
2439                        "running e2fsck is recommended");
2440
2441         /*
2442          * Check feature flags regardless of the revision level, since we
2443          * previously didn't change the revision level when setting the flags,
2444          * so there is a chance incompat flags are set on a rev 0 filesystem.
2445          */
2446         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2447                 goto failed_mount;
2448
2449         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2450
2451         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2452             blocksize > EXT4_MAX_BLOCK_SIZE) {
2453                 ext4_msg(sb, KERN_ERR,
2454                        "Unsupported filesystem blocksize %d", blocksize);
2455                 goto failed_mount;
2456         }
2457
2458         if (sb->s_blocksize != blocksize) {
2459                 /* Validate the filesystem blocksize */
2460                 if (!sb_set_blocksize(sb, blocksize)) {
2461                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2462                                         blocksize);
2463                         goto failed_mount;
2464                 }
2465
2466                 brelse(bh);
2467                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2468                 offset = do_div(logical_sb_block, blocksize);
2469                 bh = sb_bread(sb, logical_sb_block);
2470                 if (!bh) {
2471                         ext4_msg(sb, KERN_ERR,
2472                                "Can't read superblock on 2nd try");
2473                         goto failed_mount;
2474                 }
2475                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2476                 sbi->s_es = es;
2477                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2478                         ext4_msg(sb, KERN_ERR,
2479                                "Magic mismatch, very weird!");
2480                         goto failed_mount;
2481                 }
2482         }
2483
2484         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2485                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2486         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2487                                                       has_huge_files);
2488         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2489
2490         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2491                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2492                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2493         } else {
2494                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2495                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2496                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2497                     (!is_power_of_2(sbi->s_inode_size)) ||
2498                     (sbi->s_inode_size > blocksize)) {
2499                         ext4_msg(sb, KERN_ERR,
2500                                "unsupported inode size: %d",
2501                                sbi->s_inode_size);
2502                         goto failed_mount;
2503                 }
2504                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2505                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2506         }
2507
2508         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2509         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2510                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2511                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2512                     !is_power_of_2(sbi->s_desc_size)) {
2513                         ext4_msg(sb, KERN_ERR,
2514                                "unsupported descriptor size %lu",
2515                                sbi->s_desc_size);
2516                         goto failed_mount;
2517                 }
2518         } else
2519                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2520
2521         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2522         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2523         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2524                 goto cantfind_ext4;
2525
2526         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2527         if (sbi->s_inodes_per_block == 0)
2528                 goto cantfind_ext4;
2529         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2530                                         sbi->s_inodes_per_block;
2531         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2532         sbi->s_sbh = bh;
2533         sbi->s_mount_state = le16_to_cpu(es->s_state);
2534         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2535         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2536
2537         for (i = 0; i < 4; i++)
2538                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2539         sbi->s_def_hash_version = es->s_def_hash_version;
2540         i = le32_to_cpu(es->s_flags);
2541         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2542                 sbi->s_hash_unsigned = 3;
2543         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2544 #ifdef __CHAR_UNSIGNED__
2545                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2546                 sbi->s_hash_unsigned = 3;
2547 #else
2548                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2549 #endif
2550                 sb->s_dirt = 1;
2551         }
2552
2553         if (sbi->s_blocks_per_group > blocksize * 8) {
2554                 ext4_msg(sb, KERN_ERR,
2555                        "#blocks per group too big: %lu",
2556                        sbi->s_blocks_per_group);
2557                 goto failed_mount;
2558         }
2559         if (sbi->s_inodes_per_group > blocksize * 8) {
2560                 ext4_msg(sb, KERN_ERR,
2561                        "#inodes per group too big: %lu",
2562                        sbi->s_inodes_per_group);
2563                 goto failed_mount;
2564         }
2565
2566         /*
2567          * Test whether we have more sectors than will fit in sector_t,
2568          * and whether the max offset is addressable by the page cache.
2569          */
2570         if ((ext4_blocks_count(es) >
2571              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2572             (ext4_blocks_count(es) >
2573              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2574                 ext4_msg(sb, KERN_ERR, "filesystem"
2575                          " too large to mount safely on this system");
2576                 if (sizeof(sector_t) < 8)
2577                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2578                 ret = -EFBIG;
2579                 goto failed_mount;
2580         }
2581
2582         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2583                 goto cantfind_ext4;
2584
2585         /* check blocks count against device size */
2586         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2587         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2588                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2589                        "exceeds size of device (%llu blocks)",
2590                        ext4_blocks_count(es), blocks_count);
2591                 goto failed_mount;
2592         }
2593
2594         /*
2595          * It makes no sense for the first data block to be beyond the end
2596          * of the filesystem.
2597          */
2598         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2599                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2600                          "block %u is beyond end of filesystem (%llu)",
2601                          le32_to_cpu(es->s_first_data_block),
2602                          ext4_blocks_count(es));
2603                 goto failed_mount;
2604         }
2605         blocks_count = (ext4_blocks_count(es) -
2606                         le32_to_cpu(es->s_first_data_block) +
2607                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2608         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2609         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2610                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2611                        "(block count %llu, first data block %u, "
2612                        "blocks per group %lu)", sbi->s_groups_count,
2613                        ext4_blocks_count(es),
2614                        le32_to_cpu(es->s_first_data_block),
2615                        EXT4_BLOCKS_PER_GROUP(sb));
2616                 goto failed_mount;
2617         }
2618         sbi->s_groups_count = blocks_count;
2619         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2620                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2621         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2622                    EXT4_DESC_PER_BLOCK(sb);
2623         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2624                                     GFP_KERNEL);
2625         if (sbi->s_group_desc == NULL) {
2626                 ext4_msg(sb, KERN_ERR, "not enough memory");
2627                 goto failed_mount;
2628         }
2629
2630 #ifdef CONFIG_PROC_FS
2631         if (ext4_proc_root)
2632                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2633 #endif
2634
2635         bgl_lock_init(sbi->s_blockgroup_lock);
2636
2637         for (i = 0; i < db_count; i++) {
2638                 block = descriptor_loc(sb, logical_sb_block, i);
2639                 sbi->s_group_desc[i] = sb_bread(sb, block);
2640                 if (!sbi->s_group_desc[i]) {
2641                         ext4_msg(sb, KERN_ERR,
2642                                "can't read group descriptor %d", i);
2643                         db_count = i;
2644                         goto failed_mount2;
2645                 }
2646         }
2647         if (!ext4_check_descriptors(sb)) {
2648                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2649                 goto failed_mount2;
2650         }
2651         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2652                 if (!ext4_fill_flex_info(sb)) {
2653                         ext4_msg(sb, KERN_ERR,
2654                                "unable to initialize "
2655                                "flex_bg meta info!");
2656                         goto failed_mount2;
2657                 }
2658
2659         sbi->s_gdb_count = db_count;
2660         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2661         spin_lock_init(&sbi->s_next_gen_lock);
2662
2663         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2664                         ext4_count_free_blocks(sb));
2665         if (!err) {
2666                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2667                                 ext4_count_free_inodes(sb));
2668         }
2669         if (!err) {
2670                 err = percpu_counter_init(&sbi->s_dirs_counter,
2671                                 ext4_count_dirs(sb));
2672         }
2673         if (!err) {
2674                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2675         }
2676         if (err) {
2677                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2678                 goto failed_mount3;
2679         }
2680
2681         sbi->s_stripe = ext4_get_stripe_size(sbi);
2682
2683         /*
2684          * set up enough so that it can read an inode
2685          */
2686         if (!test_opt(sb, NOLOAD) &&
2687             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2688                 sb->s_op = &ext4_sops;
2689         else
2690                 sb->s_op = &ext4_nojournal_sops;
2691         sb->s_export_op = &ext4_export_ops;
2692         sb->s_xattr = ext4_xattr_handlers;
2693 #ifdef CONFIG_QUOTA
2694         sb->s_qcop = &ext4_qctl_operations;
2695         sb->dq_op = &ext4_quota_operations;
2696 #endif
2697         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2698         mutex_init(&sbi->s_orphan_lock);
2699         mutex_init(&sbi->s_resize_lock);
2700
2701         sb->s_root = NULL;
2702
2703         needs_recovery = (es->s_last_orphan != 0 ||
2704                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2705                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2706
2707         /*
2708          * The first inode we look at is the journal inode.  Don't try
2709          * root first: it may be modified in the journal!
2710          */
2711         if (!test_opt(sb, NOLOAD) &&
2712             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2713                 if (ext4_load_journal(sb, es, journal_devnum))
2714                         goto failed_mount3;
2715                 if (!(sb->s_flags & MS_RDONLY) &&
2716                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2717                         ext4_msg(sb, KERN_CRIT, "error: "
2718                                "ext4_fill_super: Journal transaction "
2719                                "%u is corrupt",
2720                                EXT4_SB(sb)->s_journal->j_failed_commit);
2721                         if (test_opt(sb, ERRORS_RO)) {
2722                                 ext4_msg(sb, KERN_CRIT,
2723                                        "Mounting filesystem read-only");
2724                                 sb->s_flags |= MS_RDONLY;
2725                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2726                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2727                         }
2728                         if (test_opt(sb, ERRORS_PANIC)) {
2729                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2730                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2731                                 ext4_commit_super(sb, 1);
2732                                 goto failed_mount4;
2733                         }
2734                 }
2735         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2736               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2737                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2738                        "suppressed and not mounted read-only");
2739                 goto failed_mount4;
2740         } else {
2741                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2742                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2743                 sbi->s_journal = NULL;
2744                 needs_recovery = 0;
2745                 goto no_journal;
2746         }
2747
2748         if (ext4_blocks_count(es) > 0xffffffffULL &&
2749             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2750                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2751                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2752                 goto failed_mount4;
2753         }
2754
2755         jbd2_journal_set_features(sbi->s_journal,
2756                                   JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2757         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
2758                 jbd2_journal_set_features(sbi->s_journal, 0, 0,
2759                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2760         else
2761                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2762                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2763
2764         /* We have now updated the journal if required, so we can
2765          * validate the data journaling mode. */
2766         switch (test_opt(sb, DATA_FLAGS)) {
2767         case 0:
2768                 /* No mode set, assume a default based on the journal
2769                  * capabilities: ORDERED_DATA if the journal can
2770                  * cope, else JOURNAL_DATA
2771                  */
2772                 if (jbd2_journal_check_available_features
2773                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2774                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2775                 else
2776                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2777                 break;
2778
2779         case EXT4_MOUNT_ORDERED_DATA:
2780         case EXT4_MOUNT_WRITEBACK_DATA:
2781                 if (!jbd2_journal_check_available_features
2782                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2783                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2784                                "requested data journaling mode");
2785                         goto failed_mount4;
2786                 }
2787         default:
2788                 break;
2789         }
2790         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2791
2792 no_journal:
2793
2794         if (test_opt(sb, NOBH)) {
2795                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2796                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2797                                 "its supported only with writeback mode");
2798                         clear_opt(sbi->s_mount_opt, NOBH);
2799                 }
2800         }
2801         /*
2802          * The jbd2_journal_load will have done any necessary log recovery,
2803          * so we can safely mount the rest of the filesystem now.
2804          */
2805
2806         root = ext4_iget(sb, EXT4_ROOT_INO);
2807         if (IS_ERR(root)) {
2808                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2809                 ret = PTR_ERR(root);
2810                 goto failed_mount4;
2811         }
2812         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2813                 iput(root);
2814                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2815                 goto failed_mount4;
2816         }
2817         sb->s_root = d_alloc_root(root);
2818         if (!sb->s_root) {
2819                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2820                 iput(root);
2821                 ret = -ENOMEM;
2822                 goto failed_mount4;
2823         }
2824
2825         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2826
2827         /* determine the minimum size of new large inodes, if present */
2828         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2829                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2830                                                      EXT4_GOOD_OLD_INODE_SIZE;
2831                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2832                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2833                         if (sbi->s_want_extra_isize <
2834                             le16_to_cpu(es->s_want_extra_isize))
2835                                 sbi->s_want_extra_isize =
2836                                         le16_to_cpu(es->s_want_extra_isize);
2837                         if (sbi->s_want_extra_isize <
2838                             le16_to_cpu(es->s_min_extra_isize))
2839                                 sbi->s_want_extra_isize =
2840                                         le16_to_cpu(es->s_min_extra_isize);
2841                 }
2842         }
2843         /* Check if enough inode space is available */
2844         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2845                                                         sbi->s_inode_size) {
2846                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2847                                                        EXT4_GOOD_OLD_INODE_SIZE;
2848                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2849                          "available");
2850         }
2851
2852         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2853                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2854                          "requested data journaling mode");
2855                 clear_opt(sbi->s_mount_opt, DELALLOC);
2856         } else if (test_opt(sb, DELALLOC))
2857                 ext4_msg(sb, KERN_INFO, "delayed allocation enabled");
2858
2859         err = ext4_setup_system_zone(sb);
2860         if (err) {
2861                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2862                          "zone (%d)\n", err);
2863                 goto failed_mount4;
2864         }
2865
2866         ext4_ext_init(sb);
2867         err = ext4_mb_init(sb, needs_recovery);
2868         if (err) {
2869                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2870                          err);
2871                 goto failed_mount4;
2872         }
2873
2874         sbi->s_kobj.kset = ext4_kset;
2875         init_completion(&sbi->s_kobj_unregister);
2876         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2877                                    "%s", sb->s_id);
2878         if (err) {
2879                 ext4_mb_release(sb);
2880                 ext4_ext_release(sb);
2881                 goto failed_mount4;
2882         };
2883
2884         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2885         ext4_orphan_cleanup(sb, es);
2886         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2887         if (needs_recovery) {
2888                 ext4_msg(sb, KERN_INFO, "recovery complete");
2889                 ext4_mark_recovery_complete(sb, es);
2890         }
2891         if (EXT4_SB(sb)->s_journal) {
2892                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2893                         descr = " journalled data mode";
2894                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2895                         descr = " ordered data mode";
2896                 else
2897                         descr = " writeback data mode";
2898         } else
2899                 descr = "out journal";
2900
2901         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2902
2903         lock_kernel();
2904         return 0;
2905
2906 cantfind_ext4:
2907         if (!silent)
2908                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2909         goto failed_mount;
2910
2911 failed_mount4:
2912         ext4_msg(sb, KERN_ERR, "mount failed");
2913         ext4_release_system_zone(sb);
2914         if (sbi->s_journal) {
2915                 jbd2_journal_destroy(sbi->s_journal);
2916                 sbi->s_journal = NULL;
2917         }
2918 failed_mount3:
2919         if (sbi->s_flex_groups) {
2920                 if (is_vmalloc_addr(sbi->s_flex_groups))
2921                         vfree(sbi->s_flex_groups);
2922                 else
2923                         kfree(sbi->s_flex_groups);
2924         }
2925         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2926         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2927         percpu_counter_destroy(&sbi->s_dirs_counter);
2928         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2929 failed_mount2:
2930         for (i = 0; i < db_count; i++)
2931                 brelse(sbi->s_group_desc[i]);
2932         kfree(sbi->s_group_desc);
2933 failed_mount:
2934         if (sbi->s_proc) {
2935                 remove_proc_entry(sb->s_id, ext4_proc_root);
2936         }
2937 #ifdef CONFIG_QUOTA
2938         for (i = 0; i < MAXQUOTAS; i++)
2939                 kfree(sbi->s_qf_names[i]);
2940 #endif
2941         ext4_blkdev_remove(sbi);
2942         brelse(bh);
2943 out_fail:
2944         sb->s_fs_info = NULL;
2945         kfree(sbi->s_blockgroup_lock);
2946         kfree(sbi);
2947         lock_kernel();
2948         return ret;
2949 }
2950
2951 /*
2952  * Setup any per-fs journal parameters now.  We'll do this both on
2953  * initial mount, once the journal has been initialised but before we've
2954  * done any recovery; and again on any subsequent remount.
2955  */
2956 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2957 {
2958         struct ext4_sb_info *sbi = EXT4_SB(sb);
2959
2960         journal->j_commit_interval = sbi->s_commit_interval;
2961         journal->j_min_batch_time = sbi->s_min_batch_time;
2962         journal->j_max_batch_time = sbi->s_max_batch_time;
2963
2964         spin_lock(&journal->j_state_lock);
2965         if (test_opt(sb, BARRIER))
2966                 journal->j_flags |= JBD2_BARRIER;
2967         else
2968                 journal->j_flags &= ~JBD2_BARRIER;
2969         if (test_opt(sb, DATA_ERR_ABORT))
2970                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
2971         else
2972                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
2973         spin_unlock(&journal->j_state_lock);
2974 }
2975
2976 static journal_t *ext4_get_journal(struct super_block *sb,
2977                                    unsigned int journal_inum)
2978 {
2979         struct inode *journal_inode;
2980         journal_t *journal;
2981
2982         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2983
2984         /* First, test for the existence of a valid inode on disk.  Bad
2985          * things happen if we iget() an unused inode, as the subsequent
2986          * iput() will try to delete it. */
2987
2988         journal_inode = ext4_iget(sb, journal_inum);
2989         if (IS_ERR(journal_inode)) {
2990                 ext4_msg(sb, KERN_ERR, "no journal found");
2991                 return NULL;
2992         }
2993         if (!journal_inode->i_nlink) {
2994                 make_bad_inode(journal_inode);
2995                 iput(journal_inode);
2996                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
2997                 return NULL;
2998         }
2999
3000         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3001                   journal_inode, journal_inode->i_size);
3002         if (!S_ISREG(journal_inode->i_mode)) {
3003                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3004                 iput(journal_inode);
3005                 return NULL;
3006         }
3007
3008         journal = jbd2_journal_init_inode(journal_inode);
3009         if (!journal) {
3010                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3011                 iput(journal_inode);
3012                 return NULL;
3013         }
3014         journal->j_private = sb;
3015         ext4_init_journal_params(sb, journal);
3016         return journal;
3017 }
3018
3019 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3020                                        dev_t j_dev)
3021 {
3022         struct buffer_head *bh;
3023         journal_t *journal;
3024         ext4_fsblk_t start;
3025         ext4_fsblk_t len;
3026         int hblock, blocksize;
3027         ext4_fsblk_t sb_block;
3028         unsigned long offset;
3029         struct ext4_super_block *es;
3030         struct block_device *bdev;
3031
3032         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3033
3034         bdev = ext4_blkdev_get(j_dev, sb);
3035         if (bdev == NULL)
3036                 return NULL;
3037
3038         if (bd_claim(bdev, sb)) {
3039                 ext4_msg(sb, KERN_ERR,
3040                         "failed to claim external journal device");
3041                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3042                 return NULL;
3043         }
3044
3045         blocksize = sb->s_blocksize;
3046         hblock = bdev_logical_block_size(bdev);
3047         if (blocksize < hblock) {
3048                 ext4_msg(sb, KERN_ERR,
3049                         "blocksize too small for journal device");
3050                 goto out_bdev;
3051         }
3052
3053         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3054         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3055         set_blocksize(bdev, blocksize);
3056         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3057                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3058                        "external journal");
3059                 goto out_bdev;
3060         }
3061
3062         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3063         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3064             !(le32_to_cpu(es->s_feature_incompat) &
3065               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3066                 ext4_msg(sb, KERN_ERR, "external journal has "
3067                                         "bad superblock");
3068                 brelse(bh);
3069                 goto out_bdev;
3070         }
3071
3072         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3073                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3074                 brelse(bh);
3075                 goto out_bdev;
3076         }
3077
3078         len = ext4_blocks_count(es);
3079         start = sb_block + 1;
3080         brelse(bh);     /* we're done with the superblock */
3081
3082         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3083                                         start, len, blocksize);
3084         if (!journal) {
3085                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3086                 goto out_bdev;
3087         }
3088         journal->j_private = sb;
3089         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3090         wait_on_buffer(journal->j_sb_buffer);
3091         if (!buffer_uptodate(journal->j_sb_buffer)) {
3092                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3093                 goto out_journal;
3094         }
3095         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3096                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3097                                         "user (unsupported) - %d",
3098                         be32_to_cpu(journal->j_superblock->s_nr_users));
3099                 goto out_journal;
3100         }
3101         EXT4_SB(sb)->journal_bdev = bdev;
3102         ext4_init_journal_params(sb, journal);
3103         return journal;
3104
3105 out_journal:
3106         jbd2_journal_destroy(journal);
3107 out_bdev:
3108         ext4_blkdev_put(bdev);
3109         return NULL;
3110 }
3111
3112 static int ext4_load_journal(struct super_block *sb,
3113                              struct ext4_super_block *es,
3114                              unsigned long journal_devnum)
3115 {
3116         journal_t *journal;
3117         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3118         dev_t journal_dev;
3119         int err = 0;
3120         int really_read_only;
3121
3122         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3123
3124         if (journal_devnum &&
3125             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3126                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3127                         "numbers have changed");
3128                 journal_dev = new_decode_dev(journal_devnum);
3129         } else
3130                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3131
3132         really_read_only = bdev_read_only(sb->s_bdev);
3133
3134         /*
3135          * Are we loading a blank journal or performing recovery after a
3136          * crash?  For recovery, we need to check in advance whether we
3137          * can get read-write access to the device.
3138          */
3139         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3140                 if (sb->s_flags & MS_RDONLY) {
3141                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3142                                         "required on readonly filesystem");
3143                         if (really_read_only) {
3144                                 ext4_msg(sb, KERN_ERR, "write access "
3145                                         "unavailable, cannot proceed");
3146                                 return -EROFS;
3147                         }
3148                         ext4_msg(sb, KERN_INFO, "write access will "
3149                                "be enabled during recovery");
3150                 }
3151         }
3152
3153         if (journal_inum && journal_dev) {
3154                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3155                        "and inode journals!");
3156                 return -EINVAL;
3157         }
3158
3159         if (journal_inum) {
3160                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3161                         return -EINVAL;
3162         } else {
3163                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3164                         return -EINVAL;
3165         }
3166
3167         if (journal->j_flags & JBD2_BARRIER)
3168                 ext4_msg(sb, KERN_INFO, "barriers enabled");
3169         else
3170                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3171
3172         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3173                 err = jbd2_journal_update_format(journal);
3174                 if (err)  {
3175                         ext4_msg(sb, KERN_ERR, "error updating journal");
3176                         jbd2_journal_destroy(journal);
3177                         return err;
3178                 }
3179         }
3180
3181         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3182                 err = jbd2_journal_wipe(journal, !really_read_only);
3183         if (!err)
3184                 err = jbd2_journal_load(journal);
3185
3186         if (err) {
3187                 ext4_msg(sb, KERN_ERR, "error loading journal");
3188                 jbd2_journal_destroy(journal);
3189                 return err;
3190         }
3191
3192         EXT4_SB(sb)->s_journal = journal;
3193         ext4_clear_journal_err(sb, es);
3194
3195         if (journal_devnum &&
3196             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3197                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3198
3199                 /* Make sure we flush the recovery flag to disk. */
3200                 ext4_commit_super(sb, 1);
3201         }
3202
3203         return 0;
3204 }
3205
3206 static int ext4_commit_super(struct super_block *sb, int sync)
3207 {
3208         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3209         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3210         int error = 0;
3211
3212         if (!sbh)
3213                 return error;
3214         if (buffer_write_io_error(sbh)) {
3215                 /*
3216                  * Oh, dear.  A previous attempt to write the
3217                  * superblock failed.  This could happen because the
3218                  * USB device was yanked out.  Or it could happen to
3219                  * be a transient write error and maybe the block will
3220                  * be remapped.  Nothing we can do but to retry the
3221                  * write and hope for the best.
3222                  */
3223                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3224                        "superblock detected");
3225                 clear_buffer_write_io_error(sbh);
3226                 set_buffer_uptodate(sbh);
3227         }
3228         /*
3229          * If the file system is mounted read-only, don't update the
3230          * superblock write time.  This avoids updating the superblock
3231          * write time when we are mounting the root file system
3232          * read/only but we need to replay the journal; at that point,
3233          * for people who are east of GMT and who make their clock
3234          * tick in localtime for Windows bug-for-bug compatibility,
3235          * the clock is set in the future, and this will cause e2fsck
3236          * to complain and force a full file system check.
3237          */
3238         if (!(sb->s_flags & MS_RDONLY))
3239                 es->s_wtime = cpu_to_le32(get_seconds());
3240         es->s_kbytes_written =
3241                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3242                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3243                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3244         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3245                                         &EXT4_SB(sb)->s_freeblocks_counter));
3246         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3247                                         &EXT4_SB(sb)->s_freeinodes_counter));
3248         sb->s_dirt = 0;
3249         BUFFER_TRACE(sbh, "marking dirty");
3250         mark_buffer_dirty(sbh);
3251         if (sync) {
3252                 error = sync_dirty_buffer(sbh);
3253                 if (error)
3254                         return error;
3255
3256                 error = buffer_write_io_error(sbh);
3257                 if (error) {
3258                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3259                                "superblock");
3260                         clear_buffer_write_io_error(sbh);
3261                         set_buffer_uptodate(sbh);
3262                 }
3263         }
3264         return error;
3265 }
3266
3267 /*
3268  * Have we just finished recovery?  If so, and if we are mounting (or
3269  * remounting) the filesystem readonly, then we will end up with a
3270  * consistent fs on disk.  Record that fact.
3271  */
3272 static void ext4_mark_recovery_complete(struct super_block *sb,
3273                                         struct ext4_super_block *es)
3274 {
3275         journal_t *journal = EXT4_SB(sb)->s_journal;
3276
3277         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3278                 BUG_ON(journal != NULL);
3279                 return;
3280         }
3281         jbd2_journal_lock_updates(journal);
3282         if (jbd2_journal_flush(journal) < 0)
3283                 goto out;
3284
3285         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3286             sb->s_flags & MS_RDONLY) {
3287                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3288                 ext4_commit_super(sb, 1);
3289         }
3290
3291 out:
3292         jbd2_journal_unlock_updates(journal);
3293 }
3294
3295 /*
3296  * If we are mounting (or read-write remounting) a filesystem whose journal
3297  * has recorded an error from a previous lifetime, move that error to the
3298  * main filesystem now.
3299  */
3300 static void ext4_clear_journal_err(struct super_block *sb,
3301                                    struct ext4_super_block *es)
3302 {
3303         journal_t *journal;
3304         int j_errno;
3305         const char *errstr;
3306
3307         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3308
3309         journal = EXT4_SB(sb)->s_journal;
3310
3311         /*
3312          * Now check for any error status which may have been recorded in the
3313          * journal by a prior ext4_error() or ext4_abort()
3314          */
3315
3316         j_errno = jbd2_journal_errno(journal);
3317         if (j_errno) {
3318                 char nbuf[16];
3319
3320                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3321                 ext4_warning(sb, __func__, "Filesystem error recorded "
3322                              "from previous mount: %s", errstr);
3323                 ext4_warning(sb, __func__, "Marking fs in need of "
3324                              "filesystem check.");
3325
3326                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3327                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3328                 ext4_commit_super(sb, 1);
3329
3330                 jbd2_journal_clear_err(journal);
3331         }
3332 }
3333
3334 /*
3335  * Force the running and committing transactions to commit,
3336  * and wait on the commit.
3337  */
3338 int ext4_force_commit(struct super_block *sb)
3339 {
3340         journal_t *journal;
3341         int ret = 0;
3342
3343         if (sb->s_flags & MS_RDONLY)
3344                 return 0;
3345
3346         journal = EXT4_SB(sb)->s_journal;
3347         if (journal)
3348                 ret = ext4_journal_force_commit(journal);
3349
3350         return ret;
3351 }
3352
3353 static void ext4_write_super(struct super_block *sb)
3354 {
3355         lock_super(sb);
3356         ext4_commit_super(sb, 1);
3357         unlock_super(sb);
3358 }
3359
3360 static int ext4_sync_fs(struct super_block *sb, int wait)
3361 {
3362         int ret = 0;
3363         tid_t target;
3364
3365         trace_ext4_sync_fs(sb, wait);
3366         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
3367                 if (wait)
3368                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
3369         }
3370         return ret;
3371 }
3372
3373 /*
3374  * LVM calls this function before a (read-only) snapshot is created.  This
3375  * gives us a chance to flush the journal completely and mark the fs clean.
3376  */
3377 static int ext4_freeze(struct super_block *sb)
3378 {
3379         int error = 0;
3380         journal_t *journal;
3381
3382         if (sb->s_flags & MS_RDONLY)
3383                 return 0;
3384
3385         journal = EXT4_SB(sb)->s_journal;
3386
3387         /* Now we set up the journal barrier. */
3388         jbd2_journal_lock_updates(journal);
3389
3390         /*
3391          * Don't clear the needs_recovery flag if we failed to flush
3392          * the journal.
3393          */
3394         error = jbd2_journal_flush(journal);
3395         if (error < 0) {
3396         out:
3397                 jbd2_journal_unlock_updates(journal);
3398                 return error;
3399         }
3400
3401         /* Journal blocked and flushed, clear needs_recovery flag. */
3402         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3403         error = ext4_commit_super(sb, 1);
3404         if (error)
3405                 goto out;
3406         return 0;
3407 }
3408
3409 /*
3410  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3411  * flag here, even though the filesystem is not technically dirty yet.
3412  */
3413 static int ext4_unfreeze(struct super_block *sb)
3414 {
3415         if (sb->s_flags & MS_RDONLY)
3416                 return 0;
3417
3418         lock_super(sb);
3419         /* Reset the needs_recovery flag before the fs is unlocked. */
3420         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3421         ext4_commit_super(sb, 1);
3422         unlock_super(sb);
3423         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3424         return 0;
3425 }
3426
3427 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3428 {
3429         struct ext4_super_block *es;
3430         struct ext4_sb_info *sbi = EXT4_SB(sb);
3431         ext4_fsblk_t n_blocks_count = 0;
3432         unsigned long old_sb_flags;
3433         struct ext4_mount_options old_opts;
3434         ext4_group_t g;
3435         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3436         int err;
3437 #ifdef CONFIG_QUOTA
3438         int i;
3439 #endif
3440
3441         lock_kernel();
3442
3443         /* Store the original options */
3444         lock_super(sb);
3445         old_sb_flags = sb->s_flags;
3446         old_opts.s_mount_opt = sbi->s_mount_opt;
3447         old_opts.s_resuid = sbi->s_resuid;
3448         old_opts.s_resgid = sbi->s_resgid;
3449         old_opts.s_commit_interval = sbi->s_commit_interval;
3450         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3451         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3452 #ifdef CONFIG_QUOTA
3453         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3454         for (i = 0; i < MAXQUOTAS; i++)
3455                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3456 #endif
3457         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3458                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3459
3460         /*
3461          * Allow the "check" option to be passed as a remount option.
3462          */
3463         if (!parse_options(data, sb, NULL, &journal_ioprio,
3464                            &n_blocks_count, 1)) {
3465                 err = -EINVAL;
3466                 goto restore_opts;
3467         }
3468
3469         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3470                 ext4_abort(sb, __func__, "Abort forced by user");
3471
3472         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3473                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3474
3475         es = sbi->s_es;
3476
3477         if (sbi->s_journal) {
3478                 ext4_init_journal_params(sb, sbi->s_journal);
3479                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3480         }
3481
3482         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3483                 n_blocks_count > ext4_blocks_count(es)) {
3484                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3485                         err = -EROFS;
3486                         goto restore_opts;
3487                 }
3488
3489                 if (*flags & MS_RDONLY) {
3490                         /*
3491                          * First of all, the unconditional stuff we have to do
3492                          * to disable replay of the journal when we next remount
3493                          */
3494                         sb->s_flags |= MS_RDONLY;
3495
3496                         /*
3497                          * OK, test if we are remounting a valid rw partition
3498                          * readonly, and if so set the rdonly flag and then
3499                          * mark the partition as valid again.
3500                          */
3501                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3502                             (sbi->s_mount_state & EXT4_VALID_FS))
3503                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3504
3505                         if (sbi->s_journal)
3506                                 ext4_mark_recovery_complete(sb, es);
3507                 } else {
3508                         /* Make sure we can mount this feature set readwrite */
3509                         if (!ext4_feature_set_ok(sb, 0)) {
3510                                 err = -EROFS;
3511                                 goto restore_opts;
3512                         }
3513                         /*
3514                          * Make sure the group descriptor checksums
3515                          * are sane.  If they aren't, refuse to remount r/w.
3516                          */
3517                         for (g = 0; g < sbi->s_groups_count; g++) {
3518                                 struct ext4_group_desc *gdp =
3519                                         ext4_get_group_desc(sb, g, NULL);
3520
3521                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3522                                         ext4_msg(sb, KERN_ERR,
3523                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3524                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3525                                                le16_to_cpu(gdp->bg_checksum));
3526                                         err = -EINVAL;
3527                                         goto restore_opts;
3528                                 }
3529                         }
3530
3531                         /*
3532                          * If we have an unprocessed orphan list hanging
3533                          * around from a previously readonly bdev mount,
3534                          * require a full umount/remount for now.
3535                          */
3536                         if (es->s_last_orphan) {
3537                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3538                                        "remount RDWR because of unprocessed "
3539                                        "orphan inode list.  Please "
3540                                        "umount/remount instead");
3541                                 err = -EINVAL;
3542                                 goto restore_opts;
3543                         }
3544
3545                         /*
3546                          * Mounting a RDONLY partition read-write, so reread
3547                          * and store the current valid flag.  (It may have
3548                          * been changed by e2fsck since we originally mounted
3549                          * the partition.)
3550                          */
3551                         if (sbi->s_journal)
3552                                 ext4_clear_journal_err(sb, es);
3553                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3554                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3555                                 goto restore_opts;
3556                         if (!ext4_setup_super(sb, es, 0))
3557                                 sb->s_flags &= ~MS_RDONLY;
3558                 }
3559         }
3560         ext4_setup_system_zone(sb);
3561         if (sbi->s_journal == NULL)
3562                 ext4_commit_super(sb, 1);
3563
3564 #ifdef CONFIG_QUOTA
3565         /* Release old quota file names */
3566         for (i = 0; i < MAXQUOTAS; i++)
3567                 if (old_opts.s_qf_names[i] &&
3568                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3569                         kfree(old_opts.s_qf_names[i]);
3570 #endif
3571         unlock_super(sb);
3572         unlock_kernel();
3573         return 0;
3574
3575 restore_opts:
3576         sb->s_flags = old_sb_flags;
3577         sbi->s_mount_opt = old_opts.s_mount_opt;
3578         sbi->s_resuid = old_opts.s_resuid;
3579         sbi->s_resgid = old_opts.s_resgid;
3580         sbi->s_commit_interval = old_opts.s_commit_interval;
3581         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3582         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3583 #ifdef CONFIG_QUOTA
3584         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3585         for (i = 0; i < MAXQUOTAS; i++) {
3586                 if (sbi->s_qf_names[i] &&
3587                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3588                         kfree(sbi->s_qf_names[i]);
3589                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3590         }
3591 #endif
3592         unlock_super(sb);
3593         unlock_kernel();
3594         return err;
3595 }
3596
3597 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3598 {
3599         struct super_block *sb = dentry->d_sb;
3600         struct ext4_sb_info *sbi = EXT4_SB(sb);
3601         struct ext4_super_block *es = sbi->s_es;
3602         u64 fsid;
3603
3604         if (test_opt(sb, MINIX_DF)) {
3605                 sbi->s_overhead_last = 0;
3606         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3607                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3608                 ext4_fsblk_t overhead = 0;
3609
3610                 /*
3611                  * Compute the overhead (FS structures).  This is constant
3612                  * for a given filesystem unless the number of block groups
3613                  * changes so we cache the previous value until it does.
3614                  */
3615
3616                 /*
3617                  * All of the blocks before first_data_block are
3618                  * overhead
3619                  */
3620                 overhead = le32_to_cpu(es->s_first_data_block);
3621
3622                 /*
3623                  * Add the overhead attributed to the superblock and
3624                  * block group descriptors.  If the sparse superblocks
3625                  * feature is turned on, then not all groups have this.
3626                  */
3627                 for (i = 0; i < ngroups; i++) {
3628                         overhead += ext4_bg_has_super(sb, i) +
3629                                 ext4_bg_num_gdb(sb, i);
3630                         cond_resched();
3631                 }
3632
3633                 /*
3634                  * Every block group has an inode bitmap, a block
3635                  * bitmap, and an inode table.
3636                  */
3637                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3638                 sbi->s_overhead_last = overhead;
3639                 smp_wmb();
3640                 sbi->s_blocks_last = ext4_blocks_count(es);
3641         }
3642
3643         buf->f_type = EXT4_SUPER_MAGIC;
3644         buf->f_bsize = sb->s_blocksize;
3645         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3646         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3647                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3648         ext4_free_blocks_count_set(es, buf->f_bfree);
3649         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3650         if (buf->f_bfree < ext4_r_blocks_count(es))
3651                 buf->f_bavail = 0;
3652         buf->f_files = le32_to_cpu(es->s_inodes_count);
3653         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3654         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3655         buf->f_namelen = EXT4_NAME_LEN;
3656         fsid = le64_to_cpup((void *)es->s_uuid) ^
3657                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3658         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3659         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3660
3661         return 0;
3662 }
3663
3664 /* Helper function for writing quotas on sync - we need to start transaction
3665  * before quota file is locked for write. Otherwise the are possible deadlocks:
3666  * Process 1                         Process 2
3667  * ext4_create()                     quota_sync()
3668  *   jbd2_journal_start()                  write_dquot()
3669  *   vfs_dq_init()                         down(dqio_mutex)
3670  *     down(dqio_mutex)                    jbd2_journal_start()
3671  *
3672  */
3673
3674 #ifdef CONFIG_QUOTA
3675
3676 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3677 {
3678         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3679 }
3680
3681 static int ext4_write_dquot(struct dquot *dquot)
3682 {
3683         int ret, err;
3684         handle_t *handle;
3685         struct inode *inode;
3686
3687         inode = dquot_to_inode(dquot);
3688         handle = ext4_journal_start(inode,
3689                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3690         if (IS_ERR(handle))
3691                 return PTR_ERR(handle);
3692         ret = dquot_commit(dquot);
3693         err = ext4_journal_stop(handle);
3694         if (!ret)
3695                 ret = err;
3696         return ret;
3697 }
3698
3699 static int ext4_acquire_dquot(struct dquot *dquot)
3700 {
3701         int ret, err;
3702         handle_t *handle;
3703
3704         handle = ext4_journal_start(dquot_to_inode(dquot),
3705                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3706         if (IS_ERR(handle))
3707                 return PTR_ERR(handle);
3708         ret = dquot_acquire(dquot);
3709         err = ext4_journal_stop(handle);
3710         if (!ret)
3711                 ret = err;
3712         return ret;
3713 }
3714
3715 static int ext4_release_dquot(struct dquot *dquot)
3716 {
3717         int ret, err;
3718         handle_t *handle;
3719
3720         handle = ext4_journal_start(dquot_to_inode(dquot),
3721                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3722         if (IS_ERR(handle)) {
3723                 /* Release dquot anyway to avoid endless cycle in dqput() */
3724                 dquot_release(dquot);
3725                 return PTR_ERR(handle);
3726         }
3727         ret = dquot_release(dquot);
3728         err = ext4_journal_stop(handle);
3729         if (!ret)
3730                 ret = err;
3731         return ret;
3732 }
3733
3734 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3735 {
3736         /* Are we journaling quotas? */
3737         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3738             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3739                 dquot_mark_dquot_dirty(dquot);
3740                 return ext4_write_dquot(dquot);
3741         } else {
3742                 return dquot_mark_dquot_dirty(dquot);
3743         }
3744 }
3745
3746 static int ext4_write_info(struct super_block *sb, int type)
3747 {
3748         int ret, err;
3749         handle_t *handle;
3750
3751         /* Data block + inode block */
3752         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3753         if (IS_ERR(handle))
3754                 return PTR_ERR(handle);
3755         ret = dquot_commit_info(sb, type);
3756         err = ext4_journal_stop(handle);
3757         if (!ret)
3758                 ret = err;
3759         return ret;
3760 }
3761
3762 /*
3763  * Turn on quotas during mount time - we need to find
3764  * the quota file and such...
3765  */
3766 static int ext4_quota_on_mount(struct super_block *sb, int type)
3767 {
3768         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3769                                   EXT4_SB(sb)->s_jquota_fmt, type);
3770 }
3771
3772 /*
3773  * Standard function to be called on quota_on
3774  */
3775 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3776                          char *name, int remount)
3777 {
3778         int err;
3779         struct path path;
3780
3781         if (!test_opt(sb, QUOTA))
3782                 return -EINVAL;
3783         /* When remounting, no checks are needed and in fact, name is NULL */
3784         if (remount)
3785                 return vfs_quota_on(sb, type, format_id, name, remount);
3786
3787         err = kern_path(name, LOOKUP_FOLLOW, &path);
3788         if (err)
3789                 return err;
3790
3791         /* Quotafile not on the same filesystem? */
3792         if (path.mnt->mnt_sb != sb) {
3793                 path_put(&path);
3794                 return -EXDEV;
3795         }
3796         /* Journaling quota? */
3797         if (EXT4_SB(sb)->s_qf_names[type]) {
3798                 /* Quotafile not in fs root? */
3799                 if (path.dentry->d_parent != sb->s_root)
3800                         ext4_msg(sb, KERN_WARNING,
3801                                 "Quota file not on filesystem root. "
3802                                 "Journaled quota will not work");
3803         }
3804
3805         /*
3806          * When we journal data on quota file, we have to flush journal to see
3807          * all updates to the file when we bypass pagecache...
3808          */
3809         if (EXT4_SB(sb)->s_journal &&
3810             ext4_should_journal_data(path.dentry->d_inode)) {
3811                 /*
3812                  * We don't need to lock updates but journal_flush() could
3813                  * otherwise be livelocked...
3814                  */
3815                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3816                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3817                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3818                 if (err) {
3819                         path_put(&path);
3820                         return err;
3821                 }
3822         }
3823
3824         err = vfs_quota_on_path(sb, type, format_id, &path);
3825         path_put(&path);
3826         return err;
3827 }
3828
3829 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3830  * acquiring the locks... As quota files are never truncated and quota code
3831  * itself serializes the operations (and noone else should touch the files)
3832  * we don't have to be afraid of races */
3833 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3834                                size_t len, loff_t off)
3835 {
3836         struct inode *inode = sb_dqopt(sb)->files[type];
3837         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3838         int err = 0;
3839         int offset = off & (sb->s_blocksize - 1);
3840         int tocopy;
3841         size_t toread;
3842         struct buffer_head *bh;
3843         loff_t i_size = i_size_read(inode);
3844
3845         if (off > i_size)
3846                 return 0;
3847         if (off+len > i_size)
3848                 len = i_size-off;
3849         toread = len;
3850         while (toread > 0) {
3851                 tocopy = sb->s_blocksize - offset < toread ?
3852                                 sb->s_blocksize - offset : toread;
3853                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3854                 if (err)
3855                         return err;
3856                 if (!bh)        /* A hole? */
3857                         memset(data, 0, tocopy);
3858                 else
3859                         memcpy(data, bh->b_data+offset, tocopy);
3860                 brelse(bh);
3861                 offset = 0;
3862                 toread -= tocopy;
3863                 data += tocopy;
3864                 blk++;
3865         }
3866         return len;
3867 }
3868
3869 /* Write to quotafile (we know the transaction is already started and has
3870  * enough credits) */
3871 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3872                                 const char *data, size_t len, loff_t off)
3873 {
3874         struct inode *inode = sb_dqopt(sb)->files[type];
3875         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3876         int err = 0;
3877         int offset = off & (sb->s_blocksize - 1);
3878         int tocopy;
3879         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3880         size_t towrite = len;
3881         struct buffer_head *bh;
3882         handle_t *handle = journal_current_handle();
3883
3884         if (EXT4_SB(sb)->s_journal && !handle) {
3885                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3886                         " cancelled because transaction is not started",
3887                         (unsigned long long)off, (unsigned long long)len);
3888                 return -EIO;
3889         }
3890         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3891         while (towrite > 0) {
3892                 tocopy = sb->s_blocksize - offset < towrite ?
3893                                 sb->s_blocksize - offset : towrite;
3894                 bh = ext4_bread(handle, inode, blk, 1, &err);
3895                 if (!bh)
3896                         goto out;
3897                 if (journal_quota) {
3898                         err = ext4_journal_get_write_access(handle, bh);
3899                         if (err) {
3900                                 brelse(bh);
3901                                 goto out;
3902                         }
3903                 }
3904                 lock_buffer(bh);
3905                 memcpy(bh->b_data+offset, data, tocopy);
3906                 flush_dcache_page(bh->b_page);
3907                 unlock_buffer(bh);
3908                 if (journal_quota)
3909                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3910                 else {
3911                         /* Always do at least ordered writes for quotas */
3912                         err = ext4_jbd2_file_inode(handle, inode);
3913                         mark_buffer_dirty(bh);
3914                 }
3915                 brelse(bh);
3916                 if (err)
3917                         goto out;
3918                 offset = 0;
3919                 towrite -= tocopy;
3920                 data += tocopy;
3921                 blk++;
3922         }
3923 out:
3924         if (len == towrite) {
3925                 mutex_unlock(&inode->i_mutex);
3926                 return err;
3927         }
3928         if (inode->i_size < off+len-towrite) {
3929                 i_size_write(inode, off+len-towrite);
3930                 EXT4_I(inode)->i_disksize = inode->i_size;
3931         }
3932         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3933         ext4_mark_inode_dirty(handle, inode);
3934         mutex_unlock(&inode->i_mutex);
3935         return len - towrite;
3936 }
3937
3938 #endif
3939
3940 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3941                        const char *dev_name, void *data, struct vfsmount *mnt)
3942 {
3943         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3944 }
3945
3946 static struct file_system_type ext4_fs_type = {
3947         .owner          = THIS_MODULE,
3948         .name           = "ext4",
3949         .get_sb         = ext4_get_sb,
3950         .kill_sb        = kill_block_super,
3951         .fs_flags       = FS_REQUIRES_DEV,
3952 };
3953
3954 #ifdef CONFIG_EXT4DEV_COMPAT
3955 static int ext4dev_get_sb(struct file_system_type *fs_type, int flags,
3956                           const char *dev_name, void *data,struct vfsmount *mnt)
3957 {
3958         printk(KERN_WARNING "EXT4-fs (%s): Update your userspace programs "
3959                "to mount using ext4\n", dev_name);
3960         printk(KERN_WARNING "EXT4-fs (%s): ext4dev backwards compatibility "
3961                "will go away by 2.6.31\n", dev_name);
3962         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3963 }
3964
3965 static struct file_system_type ext4dev_fs_type = {
3966         .owner          = THIS_MODULE,
3967         .name           = "ext4dev",
3968         .get_sb         = ext4dev_get_sb,
3969         .kill_sb        = kill_block_super,
3970         .fs_flags       = FS_REQUIRES_DEV,
3971 };
3972 MODULE_ALIAS("ext4dev");
3973 #endif
3974
3975 static int __init init_ext4_fs(void)
3976 {
3977         int err;
3978
3979         err = init_ext4_system_zone();
3980         if (err)
3981                 return err;
3982         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
3983         if (!ext4_kset)
3984                 goto out4;
3985         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
3986         err = init_ext4_mballoc();
3987         if (err)
3988                 goto out3;
3989
3990         err = init_ext4_xattr();
3991         if (err)
3992                 goto out2;
3993         err = init_inodecache();
3994         if (err)
3995                 goto out1;
3996         err = register_filesystem(&ext4_fs_type);
3997         if (err)
3998                 goto out;
3999 #ifdef CONFIG_EXT4DEV_COMPAT
4000         err = register_filesystem(&ext4dev_fs_type);
4001         if (err) {
4002                 unregister_filesystem(&ext4_fs_type);
4003                 goto out;
4004         }
4005 #endif
4006         return 0;
4007 out:
4008         destroy_inodecache();
4009 out1:
4010         exit_ext4_xattr();
4011 out2:
4012         exit_ext4_mballoc();
4013 out3:
4014         remove_proc_entry("fs/ext4", NULL);
4015         kset_unregister(ext4_kset);
4016 out4:
4017         exit_ext4_system_zone();
4018         return err;
4019 }
4020
4021 static void __exit exit_ext4_fs(void)
4022 {
4023         unregister_filesystem(&ext4_fs_type);
4024 #ifdef CONFIG_EXT4DEV_COMPAT
4025         unregister_filesystem(&ext4dev_fs_type);
4026 #endif
4027         destroy_inodecache();
4028         exit_ext4_xattr();
4029         exit_ext4_mballoc();
4030         remove_proc_entry("fs/ext4", NULL);
4031         kset_unregister(ext4_kset);
4032         exit_ext4_system_zone();
4033 }
4034
4035 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4036 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4037 MODULE_LICENSE("GPL");
4038 module_init(init_ext4_fs)
4039 module_exit(exit_ext4_fs)