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/marker.h>
  41 #include <linux/log2.h>
  42 #include <linux/crc16.h>
  43 #include <asm/uaccess.h>
  44
  45 #include "ext4.h"
  46 #include "ext4_jbd2.h"
  47 #include "xattr.h"
  48 #include "acl.h"
  49
  50 static int default_mb_history_length = 1000;
  51
  52 module_param_named(default_mb_history_length, default_mb_history_length,
  53                    int, 0644);
  54 MODULE_PARM_DESC(default_mb_history_length,
  55                  "Default number of entries saved for mb_history");
  56
  57 struct proc_dir_entry *ext4_proc_root;
  58 static struct kset *ext4_kset;
  59
  60 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  61                              unsigned long journal_devnum);
  62 static int ext4_commit_super(struct super_block *sb, int sync);
  63 static void ext4_mark_recovery_complete(struct super_block *sb,
  64                                         struct ext4_super_block *es);
  65 static void ext4_clear_journal_err(struct super_block *sb,
  66                                    struct ext4_super_block *es);
  67 static int ext4_sync_fs(struct super_block *sb, int wait);
  68 static const char *ext4_decode_error(struct super_block *sb, int errno,
  69                                      char nbuf[16]);
  70 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  71 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  72 static int ext4_unfreeze(struct super_block *sb);
  73 static void ext4_write_super(struct super_block *sb);
  74 static int ext4_freeze(struct super_block *sb);
  75
  76
  77 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  78                                struct ext4_group_desc *bg)
  79 {
  80         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  81                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  82                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  83 }
  84
  85 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  86                                struct ext4_group_desc *bg)
  87 {
  88         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  89                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  90                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  91 }
  92
  93 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  94                               struct ext4_group_desc *bg)
  95 {
  96         return le32_to_cpu(bg->bg_inode_table_lo) |
  97                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  98                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  99 }
 100
 101 __u32 ext4_free_blks_count(struct super_block *sb,
 102                               struct ext4_group_desc *bg)
 103 {
 104         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 105                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 106                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 107 }
 108
 109 __u32 ext4_free_inodes_count(struct super_block *sb,
 110                               struct ext4_group_desc *bg)
 111 {
 112         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 113                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 114                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 115 }
 116
 117 __u32 ext4_used_dirs_count(struct super_block *sb,
 118                               struct ext4_group_desc *bg)
 119 {
 120         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 121                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 122                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 123 }
 124
 125 __u32 ext4_itable_unused_count(struct super_block *sb,
 126                               struct ext4_group_desc *bg)
 127 {
 128         return le16_to_cpu(bg->bg_itable_unused_lo) |
 129                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 130                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 131 }
 132
 133 void ext4_block_bitmap_set(struct super_block *sb,
 134                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 135 {
 136         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 137         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 138                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 139 }
 140
 141 void ext4_inode_bitmap_set(struct super_block *sb,
 142                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 143 {
 144         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 145         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 146                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 147 }
 148
 149 void ext4_inode_table_set(struct super_block *sb,
 150                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 151 {
 152         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 153         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 154                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 155 }
 156
 157 void ext4_free_blks_set(struct super_block *sb,
 158                           struct ext4_group_desc *bg, __u32 count)
 159 {
 160         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 161         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 162                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 163 }
 164
 165 void ext4_free_inodes_set(struct super_block *sb,
 166                           struct ext4_group_desc *bg, __u32 count)
 167 {
 168         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 169         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 170                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 171 }
 172
 173 void ext4_used_dirs_set(struct super_block *sb,
 174                           struct ext4_group_desc *bg, __u32 count)
 175 {
 176         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 177         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 178                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 179 }
 180
 181 void ext4_itable_unused_set(struct super_block *sb,
 182                           struct ext4_group_desc *bg, __u32 count)
 183 {
 184         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 185         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 186                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 187 }
 188
 189 /*
 190  * Wrappers for jbd2_journal_start/end.
 191  *
 192  * The only special thing we need to do here is to make sure that all
 193  * journal_end calls result in the superblock being marked dirty, so
 194  * that sync() will call the filesystem's write_super callback if
 195  * appropriate.
 196  */
 197 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 198 {
 199         journal_t *journal;
 200
 201         if (sb->s_flags & MS_RDONLY)
 202                 return ERR_PTR(-EROFS);
 203
 204         /* Special case here: if the journal has aborted behind our
 205          * backs (eg. EIO in the commit thread), then we still need to
 206          * take the FS itself readonly cleanly. */
 207         journal = EXT4_SB(sb)->s_journal;
 208         if (journal) {
 209                 if (is_journal_aborted(journal)) {
 210                         ext4_abort(sb, __func__, "Detected aborted journal");
 211                         return ERR_PTR(-EROFS);
 212                 }
 213                 return jbd2_journal_start(journal, nblocks);
 214         }
 215         /*
 216          * We're not journaling, return the appropriate indication.
 217          */
 218         current->journal_info = EXT4_NOJOURNAL_HANDLE;
 219         return current->journal_info;
 220 }
 221
 222 /*
 223  * The only special thing we need to do here is to make sure that all
 224  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 225  * that sync() will call the filesystem's write_super callback if
 226  * appropriate.
 227  */
 228 int __ext4_journal_stop(const char *where, handle_t *handle)
 229 {
 230         struct super_block *sb;
 231         int err;
 232         int rc;
 233
 234         if (!ext4_handle_valid(handle)) {
 235                 /*
 236                  * Do this here since we don't call jbd2_journal_stop() in
 237                  * no-journal mode.
 238                  */
 239                 current->journal_info = NULL;
 240                 return 0;
 241         }
 242         sb = handle->h_transaction->t_journal->j_private;
 243         err = handle->h_err;
 244         rc = jbd2_journal_stop(handle);
 245
 246         if (!err)
 247                 err = rc;
 248         if (err)
 249                 __ext4_std_error(sb, where, err);
 250         return err;
 251 }
 252
 253 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 254                 struct buffer_head *bh, handle_t *handle, int err)
 255 {
 256         char nbuf[16];
 257         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 258
 259         BUG_ON(!ext4_handle_valid(handle));
 260
 261         if (bh)
 262                 BUFFER_TRACE(bh, "abort");
 263
 264         if (!handle->h_err)
 265                 handle->h_err = err;
 266
 267         if (is_handle_aborted(handle))
 268                 return;
 269
 270         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 271                caller, errstr, err_fn);
 272
 273         jbd2_journal_abort_handle(handle);
 274 }
 275
 276 /* Deal with the reporting of failure conditions on a filesystem such as
 277  * inconsistencies detected or read IO failures.
 278  *
 279  * On ext2, we can store the error state of the filesystem in the
 280  * superblock.  That is not possible on ext4, because we may have other
 281  * write ordering constraints on the superblock which prevent us from
 282  * writing it out straight away; and given that the journal is about to
 283  * be aborted, we can't rely on the current, or future, transactions to
 284  * write out the superblock safely.
 285  *
 286  * We'll just use the jbd2_journal_abort() error code to record an error in
 287  * the journal instead.  On recovery, the journal will compain about
 288  * that error until we've noted it down and cleared it.
 289  */
 290
 291 static void ext4_handle_error(struct super_block *sb)
 292 {
 293         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 294
 295         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 296         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 297
 298         if (sb->s_flags & MS_RDONLY)
 299                 return;
 300
 301         if (!test_opt(sb, ERRORS_CONT)) {
 302                 journal_t *journal = EXT4_SB(sb)->s_journal;
 303
 304                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 305                 if (journal)
 306                         jbd2_journal_abort(journal, -EIO);
 307         }
 308         if (test_opt(sb, ERRORS_RO)) {
 309                 printk(KERN_CRIT "Remounting filesystem read-only\n");
 310                 sb->s_flags |= MS_RDONLY;
 311         }
 312         ext4_commit_super(sb, 1);
 313         if (test_opt(sb, ERRORS_PANIC))
 314                 panic("EXT4-fs (device %s): panic forced after error\n",
 315                         sb->s_id);
 316 }
 317
 318 void ext4_error(struct super_block *sb, const char *function,
 319                 const char *fmt, ...)
 320 {
 321         va_list args;
 322
 323         va_start(args, fmt);
 324         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 325         vprintk(fmt, args);
 326         printk("\n");
 327         va_end(args);
 328
 329         ext4_handle_error(sb);
 330 }
 331
 332 static const char *ext4_decode_error(struct super_block *sb, int errno,
 333                                      char nbuf[16])
 334 {
 335         char *errstr = NULL;
 336
 337         switch (errno) {
 338         case -EIO:
 339                 errstr = "IO failure";
 340                 break;
 341         case -ENOMEM:
 342                 errstr = "Out of memory";
 343                 break;
 344         case -EROFS:
 345                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 346                         errstr = "Journal has aborted";
 347                 else
 348                         errstr = "Readonly filesystem";
 349                 break;
 350         default:
 351                 /* If the caller passed in an extra buffer for unknown
 352                  * errors, textualise them now.  Else we just return
 353                  * NULL. */
 354                 if (nbuf) {
 355                         /* Check for truncated error codes... */
 356                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 357                                 errstr = nbuf;
 358                 }
 359                 break;
 360         }
 361
 362         return errstr;
 363 }
 364
 365 /* __ext4_std_error decodes expected errors from journaling functions
 366  * automatically and invokes the appropriate error response.  */
 367
 368 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 369 {
 370         char nbuf[16];
 371         const char *errstr;
 372
 373         /* Special case: if the error is EROFS, and we're not already
 374          * inside a transaction, then there's really no point in logging
 375          * an error. */
 376         if (errno == -EROFS && journal_current_handle() == NULL &&
 377             (sb->s_flags & MS_RDONLY))
 378                 return;
 379
 380         errstr = ext4_decode_error(sb, errno, nbuf);
 381         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 382                sb->s_id, function, errstr);
 383
 384         ext4_handle_error(sb);
 385 }
 386
 387 /*
 388  * ext4_abort is a much stronger failure handler than ext4_error.  The
 389  * abort function may be used to deal with unrecoverable failures such
 390  * as journal IO errors or ENOMEM at a critical moment in log management.
 391  *
 392  * We unconditionally force the filesystem into an ABORT|READONLY state,
 393  * unless the error response on the fs has been set to panic in which
 394  * case we take the easy way out and panic immediately.
 395  */
 396
 397 void ext4_abort(struct super_block *sb, const char *function,
 398                 const char *fmt, ...)
 399 {
 400         va_list args;
 401
 402         printk(KERN_CRIT "ext4_abort called.\n");
 403
 404         va_start(args, fmt);
 405         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 406         vprintk(fmt, args);
 407         printk("\n");
 408         va_end(args);
 409
 410         if (test_opt(sb, ERRORS_PANIC))
 411                 panic("EXT4-fs panic from previous error\n");
 412
 413         if (sb->s_flags & MS_RDONLY)
 414                 return;
 415
 416         printk(KERN_CRIT "Remounting filesystem read-only\n");
 417         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 418         sb->s_flags |= MS_RDONLY;
 419         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 420         if (EXT4_SB(sb)->s_journal)
 421                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 422 }
 423
 424 void ext4_warning(struct super_block *sb, const char *function,
 425                   const char *fmt, ...)
 426 {
 427         va_list args;
 428
 429         va_start(args, fmt);
 430         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 431                sb->s_id, function);
 432         vprintk(fmt, args);
 433         printk("\n");
 434         va_end(args);
 435 }
 436
 437 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
 438                            const char *function, const char *fmt, ...)
 439 __releases(bitlock)
 440 __acquires(bitlock)
 441 {
 442         va_list args;
 443         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 444
 445         va_start(args, fmt);
 446         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 447         vprintk(fmt, args);
 448         printk("\n");
 449         va_end(args);
 450
 451         if (test_opt(sb, ERRORS_CONT)) {
 452                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 453                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 454                 ext4_commit_super(sb, 0);
 455                 return;
 456         }
 457         ext4_unlock_group(sb, grp);
 458         ext4_handle_error(sb);
 459         /*
 460          * We only get here in the ERRORS_RO case; relocking the group
 461          * may be dangerous, but nothing bad will happen since the
 462          * filesystem will have already been marked read/only and the
 463          * journal has been aborted.  We return 1 as a hint to callers
 464          * who might what to use the return value from
 465          * ext4_grp_locked_error() to distinguish beween the
 466          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 467          * aggressively from the ext4 function in question, with a
 468          * more appropriate error code.
 469          */
 470         ext4_lock_group(sb, grp);
 471         return;
 472 }
 473
 474 void ext4_update_dynamic_rev(struct super_block *sb)
 475 {
 476         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 477
 478         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 479                 return;
 480
 481         ext4_warning(sb, __func__,
 482                      "updating to rev %d because of new feature flag, "
 483                      "running e2fsck is recommended",
 484                      EXT4_DYNAMIC_REV);
 485
 486         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 487         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 488         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 489         /* leave es->s_feature_*compat flags alone */
 490         /* es->s_uuid will be set by e2fsck if empty */
 491
 492         /*
 493          * The rest of the superblock fields should be zero, and if not it
 494          * means they are likely already in use, so leave them alone.  We
 495          * can leave it up to e2fsck to clean up any inconsistencies there.
 496          */
 497 }
 498
 499 /*
 500  * Open the external journal device
 501  */
 502 static struct block_device *ext4_blkdev_get(dev_t dev)
 503 {
 504         struct block_device *bdev;
 505         char b[BDEVNAME_SIZE];
 506
 507         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 508         if (IS_ERR(bdev))
 509                 goto fail;
 510         return bdev;
 511
 512 fail:
 513         printk(KERN_ERR "EXT4-fs: failed to open journal device %s: %ld\n",
 514                         __bdevname(dev, b), PTR_ERR(bdev));
 515         return NULL;
 516 }
 517
 518 /*
 519  * Release the journal device
 520  */
 521 static int ext4_blkdev_put(struct block_device *bdev)
 522 {
 523         bd_release(bdev);
 524         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 525 }
 526
 527 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 528 {
 529         struct block_device *bdev;
 530         int ret = -ENODEV;
 531
 532         bdev = sbi->journal_bdev;
 533         if (bdev) {
 534                 ret = ext4_blkdev_put(bdev);
 535                 sbi->journal_bdev = NULL;
 536         }
 537         return ret;
 538 }
 539
 540 static inline struct inode *orphan_list_entry(struct list_head *l)
 541 {
 542         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 543 }
 544
 545 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 546 {
 547         struct list_head *l;
 548
 549         printk(KERN_ERR "sb orphan head is %d\n",
 550                le32_to_cpu(sbi->s_es->s_last_orphan));
 551
 552         printk(KERN_ERR "sb_info orphan list:\n");
 553         list_for_each(l, &sbi->s_orphan) {
 554                 struct inode *inode = orphan_list_entry(l);
 555                 printk(KERN_ERR "  "
 556                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 557                        inode->i_sb->s_id, inode->i_ino, inode,
 558                        inode->i_mode, inode->i_nlink,
 559                        NEXT_ORPHAN(inode));
 560         }
 561 }
 562
 563 static void ext4_put_super(struct super_block *sb)
 564 {
 565         struct ext4_sb_info *sbi = EXT4_SB(sb);
 566         struct ext4_super_block *es = sbi->s_es;
 567         int i, err;
 568
 569         ext4_release_system_zone(sb);
 570         ext4_mb_release(sb);
 571         ext4_ext_release(sb);
 572         ext4_xattr_put_super(sb);
 573         if (sbi->s_journal) {
 574                 err = jbd2_journal_destroy(sbi->s_journal);
 575                 sbi->s_journal = NULL;
 576                 if (err < 0)
 577                         ext4_abort(sb, __func__,
 578                                    "Couldn't clean up the journal");
 579         }
 580         if (!(sb->s_flags & MS_RDONLY)) {
 581                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 582                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 583                 ext4_commit_super(sb, 1);
 584         }
 585         if (sbi->s_proc) {
 586                 remove_proc_entry(sb->s_id, ext4_proc_root);
 587         }
 588         kobject_del(&sbi->s_kobj);
 589
 590         for (i = 0; i < sbi->s_gdb_count; i++)
 591                 brelse(sbi->s_group_desc[i]);
 592         kfree(sbi->s_group_desc);
 593         if (is_vmalloc_addr(sbi->s_flex_groups))
 594                 vfree(sbi->s_flex_groups);
 595         else
 596                 kfree(sbi->s_flex_groups);
 597         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 598         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 599         percpu_counter_destroy(&sbi->s_dirs_counter);
 600         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 601         brelse(sbi->s_sbh);
 602 #ifdef CONFIG_QUOTA
 603         for (i = 0; i < MAXQUOTAS; i++)
 604                 kfree(sbi->s_qf_names[i]);
 605 #endif
 606
 607         /* Debugging code just in case the in-memory inode orphan list
 608          * isn't empty.  The on-disk one can be non-empty if we've
 609          * detected an error and taken the fs readonly, but the
 610          * in-memory list had better be clean by this point. */
 611         if (!list_empty(&sbi->s_orphan))
 612                 dump_orphan_list(sb, sbi);
 613         J_ASSERT(list_empty(&sbi->s_orphan));
 614
 615         invalidate_bdev(sb->s_bdev);
 616         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 617                 /*
 618                  * Invalidate the journal device's buffers.  We don't want them
 619                  * floating about in memory - the physical journal device may
 620                  * hotswapped, and it breaks the `ro-after' testing code.
 621                  */
 622                 sync_blockdev(sbi->journal_bdev);
 623                 invalidate_bdev(sbi->journal_bdev);
 624                 ext4_blkdev_remove(sbi);
 625         }
 626         sb->s_fs_info = NULL;
 627         /*
 628          * Now that we are completely done shutting down the
 629          * superblock, we need to actually destroy the kobject.
 630          */
 631         unlock_kernel();
 632         unlock_super(sb);
 633         kobject_put(&sbi->s_kobj);
 634         wait_for_completion(&sbi->s_kobj_unregister);
 635         lock_super(sb);
 636         lock_kernel();
 637         kfree(sbi->s_blockgroup_lock);
 638         kfree(sbi);
 639 }
 640
 641 static struct kmem_cache *ext4_inode_cachep;
 642
 643 /*
 644  * Called inside transaction, so use GFP_NOFS
 645  */
 646 static struct inode *ext4_alloc_inode(struct super_block *sb)
 647 {
 648         struct ext4_inode_info *ei;
 649
 650         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 651         if (!ei)
 652                 return NULL;
 653
 654 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 655         ei->i_acl = EXT4_ACL_NOT_CACHED;
 656         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 657 #endif
 658         ei->vfs_inode.i_version = 1;
 659         ei->vfs_inode.i_data.writeback_index = 0;
 660         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 661         INIT_LIST_HEAD(&ei->i_prealloc_list);
 662         spin_lock_init(&ei->i_prealloc_lock);
 663         /*
 664          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 665          * therefore it can be null here.  Don't check it, just initialize
 666          * jinode.
 667          */
 668         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 669         ei->i_reserved_data_blocks = 0;
 670         ei->i_reserved_meta_blocks = 0;
 671         ei->i_allocated_meta_blocks = 0;
 672         ei->i_delalloc_reserved_flag = 0;
 673         spin_lock_init(&(ei->i_block_reservation_lock));
 674
 675         return &ei->vfs_inode;
 676 }
 677
 678 static void ext4_destroy_inode(struct inode *inode)
 679 {
 680         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 681                 printk("EXT4 Inode %p: orphan list check failed!\n",
 682                         EXT4_I(inode));
 683                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 684                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 685                                 true);
 686                 dump_stack();
 687         }
 688         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 689 }
 690
 691 static void init_once(void *foo)
 692 {
 693         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 694
 695         INIT_LIST_HEAD(&ei->i_orphan);
 696 #ifdef CONFIG_EXT4_FS_XATTR
 697         init_rwsem(&ei->xattr_sem);
 698 #endif
 699         init_rwsem(&ei->i_data_sem);
 700         inode_init_once(&ei->vfs_inode);
 701 }
 702
 703 static int init_inodecache(void)
 704 {
 705         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 706                                              sizeof(struct ext4_inode_info),
 707                                              0, (SLAB_RECLAIM_ACCOUNT|
 708                                                 SLAB_MEM_SPREAD),
 709                                              init_once);
 710         if (ext4_inode_cachep == NULL)
 711                 return -ENOMEM;
 712         return 0;
 713 }
 714
 715 static void destroy_inodecache(void)
 716 {
 717         kmem_cache_destroy(ext4_inode_cachep);
 718 }
 719
 720 static void ext4_clear_inode(struct inode *inode)
 721 {
 722 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 723         if (EXT4_I(inode)->i_acl &&
 724                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 725                 posix_acl_release(EXT4_I(inode)->i_acl);
 726                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 727         }
 728         if (EXT4_I(inode)->i_default_acl &&
 729                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 730                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 731                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 732         }
 733 #endif
 734         ext4_discard_preallocations(inode);
 735         if (EXT4_JOURNAL(inode))
 736                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 737                                        &EXT4_I(inode)->jinode);
 738 }
 739
 740 static inline void ext4_show_quota_options(struct seq_file *seq,
 741                                            struct super_block *sb)
 742 {
 743 #if defined(CONFIG_QUOTA)
 744         struct ext4_sb_info *sbi = EXT4_SB(sb);
 745
 746         if (sbi->s_jquota_fmt)
 747                 seq_printf(seq, ",jqfmt=%s",
 748                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 749
 750         if (sbi->s_qf_names[USRQUOTA])
 751                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 752
 753         if (sbi->s_qf_names[GRPQUOTA])
 754                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 755
 756         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 757                 seq_puts(seq, ",usrquota");
 758
 759         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 760                 seq_puts(seq, ",grpquota");
 761 #endif
 762 }
 763
 764 /*
 765  * Show an option if
 766  *  - it's set to a non-default value OR
 767  *  - if the per-sb default is different from the global default
 768  */
 769 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 770 {
 771         int def_errors;
 772         unsigned long def_mount_opts;
 773         struct super_block *sb = vfs->mnt_sb;
 774         struct ext4_sb_info *sbi = EXT4_SB(sb);
 775         struct ext4_super_block *es = sbi->s_es;
 776
 777         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 778         def_errors     = le16_to_cpu(es->s_errors);
 779
 780         if (sbi->s_sb_block != 1)
 781                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 782         if (test_opt(sb, MINIX_DF))
 783                 seq_puts(seq, ",minixdf");
 784         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 785                 seq_puts(seq, ",grpid");
 786         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 787                 seq_puts(seq, ",nogrpid");
 788         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 789             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 790                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 791         }
 792         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 793             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 794                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 795         }
 796         if (test_opt(sb, ERRORS_RO)) {
 797                 if (def_errors == EXT4_ERRORS_PANIC ||
 798                     def_errors == EXT4_ERRORS_CONTINUE) {
 799                         seq_puts(seq, ",errors=remount-ro");
 800                 }
 801         }
 802         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 803                 seq_puts(seq, ",errors=continue");
 804         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 805                 seq_puts(seq, ",errors=panic");
 806         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 807                 seq_puts(seq, ",nouid32");
 808         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 809                 seq_puts(seq, ",debug");
 810         if (test_opt(sb, OLDALLOC))
 811                 seq_puts(seq, ",oldalloc");
 812 #ifdef CONFIG_EXT4_FS_XATTR
 813         if (test_opt(sb, XATTR_USER) &&
 814                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 815                 seq_puts(seq, ",user_xattr");
 816         if (!test_opt(sb, XATTR_USER) &&
 817             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 818                 seq_puts(seq, ",nouser_xattr");
 819         }
 820 #endif
 821 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 822         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 823                 seq_puts(seq, ",acl");
 824         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 825                 seq_puts(seq, ",noacl");
 826 #endif
 827         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 828                 seq_printf(seq, ",commit=%u",
 829                            (unsigned) (sbi->s_commit_interval / HZ));
 830         }
 831         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 832                 seq_printf(seq, ",min_batch_time=%u",
 833                            (unsigned) sbi->s_min_batch_time);
 834         }
 835         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 836                 seq_printf(seq, ",max_batch_time=%u",
 837                            (unsigned) sbi->s_min_batch_time);
 838         }
 839
 840         /*
 841          * We're changing the default of barrier mount option, so
 842          * let's always display its mount state so it's clear what its
 843          * status is.
 844          */
 845         seq_puts(seq, ",barrier=");
 846         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 847         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 848                 seq_puts(seq, ",journal_async_commit");
 849         if (test_opt(sb, NOBH))
 850                 seq_puts(seq, ",nobh");
 851         if (test_opt(sb, I_VERSION))
 852                 seq_puts(seq, ",i_version");
 853         if (!test_opt(sb, DELALLOC))
 854                 seq_puts(seq, ",nodelalloc");
 855
 856
 857         if (sbi->s_stripe)
 858                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 859         /*
 860          * journal mode get enabled in different ways
 861          * So just print the value even if we didn't specify it
 862          */
 863         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 864                 seq_puts(seq, ",data=journal");
 865         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 866                 seq_puts(seq, ",data=ordered");
 867         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 868                 seq_puts(seq, ",data=writeback");
 869
 870         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 871                 seq_printf(seq, ",inode_readahead_blks=%u",
 872                            sbi->s_inode_readahead_blks);
 873
 874         if (test_opt(sb, DATA_ERR_ABORT))
 875                 seq_puts(seq, ",data_err=abort");
 876
 877         if (test_opt(sb, NO_AUTO_DA_ALLOC))
 878                 seq_puts(seq, ",noauto_da_alloc");
 879
 880         ext4_show_quota_options(seq, sb);
 881
 882         return 0;
 883 }
 884
 885 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 886                                         u64 ino, u32 generation)
 887 {
 888         struct inode *inode;
 889
 890         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 891                 return ERR_PTR(-ESTALE);
 892         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 893                 return ERR_PTR(-ESTALE);
 894
 895         /* iget isn't really right if the inode is currently unallocated!!
 896          *
 897          * ext4_read_inode will return a bad_inode if the inode had been
 898          * deleted, so we should be safe.
 899          *
 900          * Currently we don't know the generation for parent directory, so
 901          * a generation of 0 means "accept any"
 902          */
 903         inode = ext4_iget(sb, ino);
 904         if (IS_ERR(inode))
 905                 return ERR_CAST(inode);
 906         if (generation && inode->i_generation != generation) {
 907                 iput(inode);
 908                 return ERR_PTR(-ESTALE);
 909         }
 910
 911         return inode;
 912 }
 913
 914 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 915                                         int fh_len, int fh_type)
 916 {
 917         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 918                                     ext4_nfs_get_inode);
 919 }
 920
 921 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 922                                         int fh_len, int fh_type)
 923 {
 924         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 925                                     ext4_nfs_get_inode);
 926 }
 927
 928 /*
 929  * Try to release metadata pages (indirect blocks, directories) which are
 930  * mapped via the block device.  Since these pages could have journal heads
 931  * which would prevent try_to_free_buffers() from freeing them, we must use
 932  * jbd2 layer's try_to_free_buffers() function to release them.
 933  */
 934 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 935                                  gfp_t wait)
 936 {
 937         journal_t *journal = EXT4_SB(sb)->s_journal;
 938
 939         WARN_ON(PageChecked(page));
 940         if (!page_has_buffers(page))
 941                 return 0;
 942         if (journal)
 943                 return jbd2_journal_try_to_free_buffers(journal, page,
 944                                                         wait & ~__GFP_WAIT);
 945         return try_to_free_buffers(page);
 946 }
 947
 948 #ifdef CONFIG_QUOTA
 949 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 950 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 951
 952 static int ext4_write_dquot(struct dquot *dquot);
 953 static int ext4_acquire_dquot(struct dquot *dquot);
 954 static int ext4_release_dquot(struct dquot *dquot);
 955 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 956 static int ext4_write_info(struct super_block *sb, int type);
 957 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 958                                 char *path, int remount);
 959 static int ext4_quota_on_mount(struct super_block *sb, int type);
 960 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 961                                size_t len, loff_t off);
 962 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 963                                 const char *data, size_t len, loff_t off);
 964
 965 static struct dquot_operations ext4_quota_operations = {
 966         .initialize     = dquot_initialize,
 967         .drop           = dquot_drop,
 968         .alloc_space    = dquot_alloc_space,
 969         .reserve_space  = dquot_reserve_space,
 970         .claim_space    = dquot_claim_space,
 971         .release_rsv    = dquot_release_reserved_space,
 972         .get_reserved_space = ext4_get_reserved_space,
 973         .alloc_inode    = dquot_alloc_inode,
 974         .free_space     = dquot_free_space,
 975         .free_inode     = dquot_free_inode,
 976         .transfer       = dquot_transfer,
 977         .write_dquot    = ext4_write_dquot,
 978         .acquire_dquot  = ext4_acquire_dquot,
 979         .release_dquot  = ext4_release_dquot,
 980         .mark_dirty     = ext4_mark_dquot_dirty,
 981         .write_info     = ext4_write_info,
 982         .alloc_dquot    = dquot_alloc,
 983         .destroy_dquot  = dquot_destroy,
 984 };
 985
 986 static struct quotactl_ops ext4_qctl_operations = {
 987         .quota_on       = ext4_quota_on,
 988         .quota_off      = vfs_quota_off,
 989         .quota_sync     = vfs_quota_sync,
 990         .get_info       = vfs_get_dqinfo,
 991         .set_info       = vfs_set_dqinfo,
 992         .get_dqblk      = vfs_get_dqblk,
 993         .set_dqblk      = vfs_set_dqblk
 994 };
 995 #endif
 996
 997 static const struct super_operations ext4_sops = {
 998         .alloc_inode    = ext4_alloc_inode,
 999         .destroy_inode  = ext4_destroy_inode,
1000         .write_inode    = ext4_write_inode,
1001         .dirty_inode    = ext4_dirty_inode,
1002         .delete_inode   = ext4_delete_inode,
1003         .put_super      = ext4_put_super,
1004         .sync_fs        = ext4_sync_fs,
1005         .freeze_fs      = ext4_freeze,
1006         .unfreeze_fs    = ext4_unfreeze,
1007         .statfs         = ext4_statfs,
1008         .remount_fs     = ext4_remount,
1009         .clear_inode    = ext4_clear_inode,
1010         .show_options   = ext4_show_options,
1011 #ifdef CONFIG_QUOTA
1012         .quota_read     = ext4_quota_read,
1013         .quota_write    = ext4_quota_write,
1014 #endif
1015         .bdev_try_to_free_page = bdev_try_to_free_page,
1016 };
1017
1018 static const struct super_operations ext4_nojournal_sops = {
1019         .alloc_inode    = ext4_alloc_inode,
1020         .destroy_inode  = ext4_destroy_inode,
1021         .write_inode    = ext4_write_inode,
1022         .dirty_inode    = ext4_dirty_inode,
1023         .delete_inode   = ext4_delete_inode,
1024         .write_super    = ext4_write_super,
1025         .put_super      = ext4_put_super,
1026         .statfs         = ext4_statfs,
1027         .remount_fs     = ext4_remount,
1028         .clear_inode    = ext4_clear_inode,
1029         .show_options   = ext4_show_options,
1030 #ifdef CONFIG_QUOTA
1031         .quota_read     = ext4_quota_read,
1032         .quota_write    = ext4_quota_write,
1033 #endif
1034         .bdev_try_to_free_page = bdev_try_to_free_page,
1035 };
1036
1037 static const struct export_operations ext4_export_ops = {
1038         .fh_to_dentry = ext4_fh_to_dentry,
1039         .fh_to_parent = ext4_fh_to_parent,
1040         .get_parent = ext4_get_parent,
1041 };
1042
1043 enum {
1044         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1045         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1046         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1047         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1048         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1049         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1050         Opt_journal_update, Opt_journal_dev,
1051         Opt_journal_checksum, Opt_journal_async_commit,
1052         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1053         Opt_data_err_abort, Opt_data_err_ignore, Opt_mb_history_length,
1054         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1055         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
1056         Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err, Opt_resize,
1057         Opt_usrquota, Opt_grpquota, Opt_i_version,
1058         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1059         Opt_block_validity, Opt_noblock_validity,
1060         Opt_inode_readahead_blks, Opt_journal_ioprio
1061 };
1062
1063 static const match_table_t tokens = {
1064         {Opt_bsd_df, "bsddf"},
1065         {Opt_minix_df, "minixdf"},
1066         {Opt_grpid, "grpid"},
1067         {Opt_grpid, "bsdgroups"},
1068         {Opt_nogrpid, "nogrpid"},
1069         {Opt_nogrpid, "sysvgroups"},
1070         {Opt_resgid, "resgid=%u"},
1071         {Opt_resuid, "resuid=%u"},
1072         {Opt_sb, "sb=%u"},
1073         {Opt_err_cont, "errors=continue"},
1074         {Opt_err_panic, "errors=panic"},
1075         {Opt_err_ro, "errors=remount-ro"},
1076         {Opt_nouid32, "nouid32"},
1077         {Opt_debug, "debug"},
1078         {Opt_oldalloc, "oldalloc"},
1079         {Opt_orlov, "orlov"},
1080         {Opt_user_xattr, "user_xattr"},
1081         {Opt_nouser_xattr, "nouser_xattr"},
1082         {Opt_acl, "acl"},
1083         {Opt_noacl, "noacl"},
1084         {Opt_noload, "noload"},
1085         {Opt_nobh, "nobh"},
1086         {Opt_bh, "bh"},
1087         {Opt_commit, "commit=%u"},
1088         {Opt_min_batch_time, "min_batch_time=%u"},
1089         {Opt_max_batch_time, "max_batch_time=%u"},
1090         {Opt_journal_update, "journal=update"},
1091         {Opt_journal_dev, "journal_dev=%u"},
1092         {Opt_journal_checksum, "journal_checksum"},
1093         {Opt_journal_async_commit, "journal_async_commit"},
1094         {Opt_abort, "abort"},
1095         {Opt_data_journal, "data=journal"},
1096         {Opt_data_ordered, "data=ordered"},
1097         {Opt_data_writeback, "data=writeback"},
1098         {Opt_data_err_abort, "data_err=abort"},
1099         {Opt_data_err_ignore, "data_err=ignore"},
1100         {Opt_mb_history_length, "mb_history_length=%u"},
1101         {Opt_offusrjquota, "usrjquota="},
1102         {Opt_usrjquota, "usrjquota=%s"},
1103         {Opt_offgrpjquota, "grpjquota="},
1104         {Opt_grpjquota, "grpjquota=%s"},
1105         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1106         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1107         {Opt_grpquota, "grpquota"},
1108         {Opt_noquota, "noquota"},
1109         {Opt_quota, "quota"},
1110         {Opt_usrquota, "usrquota"},
1111         {Opt_barrier, "barrier=%u"},
1112         {Opt_barrier, "barrier"},
1113         {Opt_nobarrier, "nobarrier"},
1114         {Opt_i_version, "i_version"},
1115         {Opt_stripe, "stripe=%u"},
1116         {Opt_resize, "resize"},
1117         {Opt_delalloc, "delalloc"},
1118         {Opt_nodelalloc, "nodelalloc"},
1119         {Opt_block_validity, "block_validity"},
1120         {Opt_noblock_validity, "noblock_validity"},
1121         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1122         {Opt_journal_ioprio, "journal_ioprio=%u"},
1123         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1124         {Opt_auto_da_alloc, "auto_da_alloc"},
1125         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1126         {Opt_err, NULL},
1127 };
1128
1129 static ext4_fsblk_t get_sb_block(void **data)
1130 {
1131         ext4_fsblk_t    sb_block;
1132         char            *options = (char *) *data;
1133
1134         if (!options || strncmp(options, "sb=", 3) != 0)
1135                 return 1;       /* Default location */
1136
1137         options += 3;
1138         /* TODO: use simple_strtoll with >32bit ext4 */
1139         sb_block = simple_strtoul(options, &options, 0);
1140         if (*options && *options != ',') {
1141                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1142                        (char *) *data);
1143                 return 1;
1144         }
1145         if (*options == ',')
1146                 options++;
1147         *data = (void *) options;
1148
1149         return sb_block;
1150 }
1151
1152 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1153
1154 static int parse_options(char *options, struct super_block *sb,
1155                          unsigned long *journal_devnum,
1156                          unsigned int *journal_ioprio,
1157                          ext4_fsblk_t *n_blocks_count, int is_remount)
1158 {
1159         struct ext4_sb_info *sbi = EXT4_SB(sb);
1160         char *p;
1161         substring_t args[MAX_OPT_ARGS];
1162         int data_opt = 0;
1163         int option;
1164 #ifdef CONFIG_QUOTA
1165         int qtype, qfmt;
1166         char *qname;
1167 #endif
1168
1169         if (!options)
1170                 return 1;
1171
1172         while ((p = strsep(&options, ",")) != NULL) {
1173                 int token;
1174                 if (!*p)
1175                         continue;
1176
1177                 token = match_token(p, tokens, args);
1178                 switch (token) {
1179                 case Opt_bsd_df:
1180                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1181                         break;
1182                 case Opt_minix_df:
1183                         set_opt(sbi->s_mount_opt, MINIX_DF);
1184                         break;
1185                 case Opt_grpid:
1186                         set_opt(sbi->s_mount_opt, GRPID);
1187                         break;
1188                 case Opt_nogrpid:
1189                         clear_opt(sbi->s_mount_opt, GRPID);
1190                         break;
1191                 case Opt_resuid:
1192                         if (match_int(&args[0], &option))
1193                                 return 0;
1194                         sbi->s_resuid = option;
1195                         break;
1196                 case Opt_resgid:
1197                         if (match_int(&args[0], &option))
1198                                 return 0;
1199                         sbi->s_resgid = option;
1200                         break;
1201                 case Opt_sb:
1202                         /* handled by get_sb_block() instead of here */
1203                         /* *sb_block = match_int(&args[0]); */
1204                         break;
1205                 case Opt_err_panic:
1206                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1207                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1208                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1209                         break;
1210                 case Opt_err_ro:
1211                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1212                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1213                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1214                         break;
1215                 case Opt_err_cont:
1216                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1217                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1218                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1219                         break;
1220                 case Opt_nouid32:
1221                         set_opt(sbi->s_mount_opt, NO_UID32);
1222                         break;
1223                 case Opt_debug:
1224                         set_opt(sbi->s_mount_opt, DEBUG);
1225                         break;
1226                 case Opt_oldalloc:
1227                         set_opt(sbi->s_mount_opt, OLDALLOC);
1228                         break;
1229                 case Opt_orlov:
1230                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1231                         break;
1232 #ifdef CONFIG_EXT4_FS_XATTR
1233                 case Opt_user_xattr:
1234                         set_opt(sbi->s_mount_opt, XATTR_USER);
1235                         break;
1236                 case Opt_nouser_xattr:
1237                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1238                         break;
1239 #else
1240                 case Opt_user_xattr:
1241                 case Opt_nouser_xattr:
1242                         printk(KERN_ERR "EXT4 (no)user_xattr options "
1243                                "not supported\n");
1244                         break;
1245 #endif
1246 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1247                 case Opt_acl:
1248                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1249                         break;
1250                 case Opt_noacl:
1251                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1252                         break;
1253 #else
1254                 case Opt_acl:
1255                 case Opt_noacl:
1256                         printk(KERN_ERR "EXT4 (no)acl options "
1257                                "not supported\n");
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                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1268                                        "journal on remount\n");
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                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1276                                        "journal on remount\n");
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                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1285                         break;
1286                 case Opt_journal_async_commit:
1287                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1288                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1289                         break;
1290                 case Opt_noload:
1291                         set_opt(sbi->s_mount_opt, NOLOAD);
1292                         break;
1293                 case Opt_commit:
1294                         if (match_int(&args[0], &option))
1295                                 return 0;
1296                         if (option < 0)
1297                                 return 0;
1298                         if (option == 0)
1299                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1300                         sbi->s_commit_interval = HZ * option;
1301                         break;
1302                 case Opt_max_batch_time:
1303                         if (match_int(&args[0], &option))
1304                                 return 0;
1305                         if (option < 0)
1306                                 return 0;
1307                         if (option == 0)
1308                                 option = EXT4_DEF_MAX_BATCH_TIME;
1309                         sbi->s_max_batch_time = option;
1310                         break;
1311                 case Opt_min_batch_time:
1312                         if (match_int(&args[0], &option))
1313                                 return 0;
1314                         if (option < 0)
1315                                 return 0;
1316                         sbi->s_min_batch_time = option;
1317                         break;
1318                 case Opt_data_journal:
1319                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1320                         goto datacheck;
1321                 case Opt_data_ordered:
1322                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1323                         goto datacheck;
1324                 case Opt_data_writeback:
1325                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1326                 datacheck:
1327                         if (is_remount) {
1328                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1329                                                 != data_opt) {
1330                                         printk(KERN_ERR
1331                                                 "EXT4-fs: cannot change data "
1332                                                 "mode on remount\n");
1333                                         return 0;
1334                                 }
1335                         } else {
1336                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1337                                 sbi->s_mount_opt |= data_opt;
1338                         }
1339                         break;
1340                 case Opt_data_err_abort:
1341                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1342                         break;
1343                 case Opt_data_err_ignore:
1344                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1345                         break;
1346                 case Opt_mb_history_length:
1347                         if (match_int(&args[0], &option))
1348                                 return 0;
1349                         if (option < 0)
1350                                 return 0;
1351                         sbi->s_mb_history_max = option;
1352                         break;
1353 #ifdef CONFIG_QUOTA
1354                 case Opt_usrjquota:
1355                         qtype = USRQUOTA;
1356                         goto set_qf_name;
1357                 case Opt_grpjquota:
1358                         qtype = GRPQUOTA;
1359 set_qf_name:
1360                         if (sb_any_quota_loaded(sb) &&
1361                             !sbi->s_qf_names[qtype]) {
1362                                 printk(KERN_ERR
1363                                        "EXT4-fs: Cannot change journaled "
1364                                        "quota options when quota turned on.\n");
1365                                 return 0;
1366                         }
1367                         qname = match_strdup(&args[0]);
1368                         if (!qname) {
1369                                 printk(KERN_ERR
1370                                         "EXT4-fs: not enough memory for "
1371                                         "storing quotafile name.\n");
1372                                 return 0;
1373                         }
1374                         if (sbi->s_qf_names[qtype] &&
1375                             strcmp(sbi->s_qf_names[qtype], qname)) {
1376                                 printk(KERN_ERR
1377                                         "EXT4-fs: %s quota file already "
1378                                         "specified.\n", QTYPE2NAME(qtype));
1379                                 kfree(qname);
1380                                 return 0;
1381                         }
1382                         sbi->s_qf_names[qtype] = qname;
1383                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1384                                 printk(KERN_ERR
1385                                         "EXT4-fs: quotafile must be on "
1386                                         "filesystem root.\n");
1387                                 kfree(sbi->s_qf_names[qtype]);
1388                                 sbi->s_qf_names[qtype] = NULL;
1389                                 return 0;
1390                         }
1391                         set_opt(sbi->s_mount_opt, QUOTA);
1392                         break;
1393                 case Opt_offusrjquota:
1394                         qtype = USRQUOTA;
1395                         goto clear_qf_name;
1396                 case Opt_offgrpjquota:
1397                         qtype = GRPQUOTA;
1398 clear_qf_name:
1399                         if (sb_any_quota_loaded(sb) &&
1400                             sbi->s_qf_names[qtype]) {
1401                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1402                                         "journaled quota options when "
1403                                         "quota turned on.\n");
1404                                 return 0;
1405                         }
1406                         /*
1407                          * The space will be released later when all options
1408                          * are confirmed to be correct
1409                          */
1410                         sbi->s_qf_names[qtype] = NULL;
1411                         break;
1412                 case Opt_jqfmt_vfsold:
1413                         qfmt = QFMT_VFS_OLD;
1414                         goto set_qf_format;
1415                 case Opt_jqfmt_vfsv0:
1416                         qfmt = QFMT_VFS_V0;
1417 set_qf_format:
1418                         if (sb_any_quota_loaded(sb) &&
1419                             sbi->s_jquota_fmt != qfmt) {
1420                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1421                                         "journaled quota options when "
1422                                         "quota turned on.\n");
1423                                 return 0;
1424                         }
1425                         sbi->s_jquota_fmt = qfmt;
1426                         break;
1427                 case Opt_quota:
1428                 case Opt_usrquota:
1429                         set_opt(sbi->s_mount_opt, QUOTA);
1430                         set_opt(sbi->s_mount_opt, USRQUOTA);
1431                         break;
1432                 case Opt_grpquota:
1433                         set_opt(sbi->s_mount_opt, QUOTA);
1434                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1435                         break;
1436                 case Opt_noquota:
1437                         if (sb_any_quota_loaded(sb)) {
1438                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1439                                         "options when quota turned on.\n");
1440                                 return 0;
1441                         }
1442                         clear_opt(sbi->s_mount_opt, QUOTA);
1443                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1444                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1445                         break;
1446 #else
1447                 case Opt_quota:
1448                 case Opt_usrquota:
1449                 case Opt_grpquota:
1450                         printk(KERN_ERR
1451                                 "EXT4-fs: quota options not supported.\n");
1452                         break;
1453                 case Opt_usrjquota:
1454                 case Opt_grpjquota:
1455                 case Opt_offusrjquota:
1456                 case Opt_offgrpjquota:
1457                 case Opt_jqfmt_vfsold:
1458                 case Opt_jqfmt_vfsv0:
1459                         printk(KERN_ERR
1460                                 "EXT4-fs: journaled quota options not "
1461                                 "supported.\n");
1462                         break;
1463                 case Opt_noquota:
1464                         break;
1465 #endif
1466                 case Opt_abort:
1467                         set_opt(sbi->s_mount_opt, ABORT);
1468                         break;
1469                 case Opt_nobarrier:
1470                         clear_opt(sbi->s_mount_opt, BARRIER);
1471                         break;
1472                 case Opt_barrier:
1473                         if (match_int(&args[0], &option)) {
1474                                 set_opt(sbi->s_mount_opt, BARRIER);
1475                                 break;
1476                         }
1477                         if (option)
1478                                 set_opt(sbi->s_mount_opt, BARRIER);
1479                         else
1480                                 clear_opt(sbi->s_mount_opt, BARRIER);
1481                         break;
1482                 case Opt_ignore:
1483                         break;
1484                 case Opt_resize:
1485                         if (!is_remount) {
1486                                 printk("EXT4-fs: resize option only available "
1487                                         "for remount\n");
1488                                 return 0;
1489                         }
1490                         if (match_int(&args[0], &option) != 0)
1491                                 return 0;
1492                         *n_blocks_count = option;
1493                         break;
1494                 case Opt_nobh:
1495                         set_opt(sbi->s_mount_opt, NOBH);
1496                         break;
1497                 case Opt_bh:
1498                         clear_opt(sbi->s_mount_opt, NOBH);
1499                         break;
1500                 case Opt_i_version:
1501                         set_opt(sbi->s_mount_opt, I_VERSION);
1502                         sb->s_flags |= MS_I_VERSION;
1503                         break;
1504                 case Opt_nodelalloc:
1505                         clear_opt(sbi->s_mount_opt, DELALLOC);
1506                         break;
1507                 case Opt_stripe:
1508                         if (match_int(&args[0], &option))
1509                                 return 0;
1510                         if (option < 0)
1511                                 return 0;
1512                         sbi->s_stripe = option;
1513                         break;
1514                 case Opt_delalloc:
1515                         set_opt(sbi->s_mount_opt, DELALLOC);
1516                         break;
1517                 case Opt_block_validity:
1518                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1519                         break;
1520                 case Opt_noblock_validity:
1521                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1522                         break;
1523                 case Opt_inode_readahead_blks:
1524                         if (match_int(&args[0], &option))
1525                                 return 0;
1526                         if (option < 0 || option > (1 << 30))
1527                                 return 0;
1528                         if (!is_power_of_2(option)) {
1529                                 printk(KERN_ERR "EXT4-fs: inode_readahead_blks"
1530                                        " must be a power of 2\n");
1531                                 return 0;
1532                         }
1533                         sbi->s_inode_readahead_blks = option;
1534                         break;
1535                 case Opt_journal_ioprio:
1536                         if (match_int(&args[0], &option))
1537                                 return 0;
1538                         if (option < 0 || option > 7)
1539                                 break;
1540                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1541                                                             option);
1542                         break;
1543                 case Opt_noauto_da_alloc:
1544                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1545                         break;
1546                 case Opt_auto_da_alloc:
1547                         if (match_int(&args[0], &option)) {
1548                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1549                                 break;
1550                         }
1551                         if (option)
1552                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1553                         else
1554                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1555                         break;
1556                 default:
1557                         printk(KERN_ERR
1558                                "EXT4-fs: Unrecognized mount option \"%s\" "
1559                                "or missing value\n", p);
1560                         return 0;
1561                 }
1562         }
1563 #ifdef CONFIG_QUOTA
1564         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1565                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1566                      sbi->s_qf_names[USRQUOTA])
1567                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1568
1569                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1570                      sbi->s_qf_names[GRPQUOTA])
1571                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1572
1573                 if ((sbi->s_qf_names[USRQUOTA] &&
1574                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1575                     (sbi->s_qf_names[GRPQUOTA] &&
1576                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1577                         printk(KERN_ERR "EXT4-fs: old and new quota "
1578                                         "format mixing.\n");
1579                         return 0;
1580                 }
1581
1582                 if (!sbi->s_jquota_fmt) {
1583                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1584                                         "not specified.\n");
1585                         return 0;
1586                 }
1587         } else {
1588                 if (sbi->s_jquota_fmt) {
1589                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1590                                         "specified with no journaling "
1591                                         "enabled.\n");
1592                         return 0;
1593                 }
1594         }
1595 #endif
1596         return 1;
1597 }
1598
1599 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1600                             int read_only)
1601 {
1602         struct ext4_sb_info *sbi = EXT4_SB(sb);
1603         int res = 0;
1604
1605         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1606                 printk(KERN_ERR "EXT4-fs warning: revision level too high, "
1607                        "forcing read-only mode\n");
1608                 res = MS_RDONLY;
1609         }
1610         if (read_only)
1611                 return res;
1612         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1613                 printk(KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1614                        "running e2fsck is recommended\n");
1615         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1616                 printk(KERN_WARNING
1617                        "EXT4-fs warning: mounting fs with errors, "
1618                        "running e2fsck is recommended\n");
1619         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1620                  le16_to_cpu(es->s_mnt_count) >=
1621                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1622                 printk(KERN_WARNING
1623                        "EXT4-fs warning: maximal mount count reached, "
1624                        "running e2fsck is recommended\n");
1625         else if (le32_to_cpu(es->s_checkinterval) &&
1626                 (le32_to_cpu(es->s_lastcheck) +
1627                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1628                 printk(KERN_WARNING
1629                        "EXT4-fs warning: checktime reached, "
1630                        "running e2fsck is recommended\n");
1631         if (!sbi->s_journal)
1632                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1633         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1634                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1635         le16_add_cpu(&es->s_mnt_count, 1);
1636         es->s_mtime = cpu_to_le32(get_seconds());
1637         ext4_update_dynamic_rev(sb);
1638         if (sbi->s_journal)
1639                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1640
1641         ext4_commit_super(sb, 1);
1642         if (test_opt(sb, DEBUG))
1643                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1644                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1645                         sb->s_blocksize,
1646                         sbi->s_groups_count,
1647                         EXT4_BLOCKS_PER_GROUP(sb),
1648                         EXT4_INODES_PER_GROUP(sb),
1649                         sbi->s_mount_opt);
1650
1651         if (EXT4_SB(sb)->s_journal) {
1652                 printk(KERN_INFO "EXT4 FS on %s, %s journal on %s\n",
1653                        sb->s_id, EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1654                        "external", EXT4_SB(sb)->s_journal->j_devname);
1655         } else {
1656                 printk(KERN_INFO "EXT4 FS on %s, no journal\n", sb->s_id);
1657         }
1658         return res;
1659 }
1660
1661 static int ext4_fill_flex_info(struct super_block *sb)
1662 {
1663         struct ext4_sb_info *sbi = EXT4_SB(sb);
1664         struct ext4_group_desc *gdp = NULL;
1665         ext4_group_t flex_group_count;
1666         ext4_group_t flex_group;
1667         int groups_per_flex = 0;
1668         size_t size;
1669         int i;
1670
1671         if (!sbi->s_es->s_log_groups_per_flex) {
1672                 sbi->s_log_groups_per_flex = 0;
1673                 return 1;
1674         }
1675
1676         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1677         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1678
1679         /* We allocate both existing and potentially added groups */
1680         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1681                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1682                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1683         size = flex_group_count * sizeof(struct flex_groups);
1684         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1685         if (sbi->s_flex_groups == NULL) {
1686                 sbi->s_flex_groups = vmalloc(size);
1687                 if (sbi->s_flex_groups)
1688                         memset(sbi->s_flex_groups, 0, size);
1689         }
1690         if (sbi->s_flex_groups == NULL) {
1691                 printk(KERN_ERR "EXT4-fs: not enough memory for "
1692                                 "%u flex groups\n", flex_group_count);
1693                 goto failed;
1694         }
1695
1696         for (i = 0; i < sbi->s_groups_count; i++) {
1697                 gdp = ext4_get_group_desc(sb, i, NULL);
1698
1699                 flex_group = ext4_flex_group(sbi, i);
1700                 atomic_set(&sbi->s_flex_groups[flex_group].free_inodes,
1701                            ext4_free_inodes_count(sb, gdp));
1702                 atomic_set(&sbi->s_flex_groups[flex_group].free_blocks,
1703                            ext4_free_blks_count(sb, gdp));
1704                 atomic_set(&sbi->s_flex_groups[flex_group].used_dirs,
1705                            ext4_used_dirs_count(sb, gdp));
1706         }
1707
1708         return 1;
1709 failed:
1710         return 0;
1711 }
1712
1713 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1714                             struct ext4_group_desc *gdp)
1715 {
1716         __u16 crc = 0;
1717
1718         if (sbi->s_es->s_feature_ro_compat &
1719             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1720                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1721                 __le32 le_group = cpu_to_le32(block_group);
1722
1723                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1724                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1725                 crc = crc16(crc, (__u8 *)gdp, offset);
1726                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1727                 /* for checksum of struct ext4_group_desc do the rest...*/
1728                 if ((sbi->s_es->s_feature_incompat &
1729                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1730                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1731                         crc = crc16(crc, (__u8 *)gdp + offset,
1732                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1733                                         offset);
1734         }
1735
1736         return cpu_to_le16(crc);
1737 }
1738
1739 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1740                                 struct ext4_group_desc *gdp)
1741 {
1742         if ((sbi->s_es->s_feature_ro_compat &
1743              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1744             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1745                 return 0;
1746
1747         return 1;
1748 }
1749
1750 /* Called at mount-time, super-block is locked */
1751 static int ext4_check_descriptors(struct super_block *sb)
1752 {
1753         struct ext4_sb_info *sbi = EXT4_SB(sb);
1754         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1755         ext4_fsblk_t last_block;
1756         ext4_fsblk_t block_bitmap;
1757         ext4_fsblk_t inode_bitmap;
1758         ext4_fsblk_t inode_table;
1759         int flexbg_flag = 0;
1760         ext4_group_t i;
1761
1762         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1763                 flexbg_flag = 1;
1764
1765         ext4_debug("Checking group descriptors");
1766
1767         for (i = 0; i < sbi->s_groups_count; i++) {
1768                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1769
1770                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1771                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1772                 else
1773                         last_block = first_block +
1774                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1775
1776                 block_bitmap = ext4_block_bitmap(sb, gdp);
1777                 if (block_bitmap < first_block || block_bitmap > last_block) {
1778                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1779                                "Block bitmap for group %u not in group "
1780                                "(block %llu)!\n", i, block_bitmap);
1781                         return 0;
1782                 }
1783                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1784                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1785                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1786                                "Inode bitmap for group %u not in group "
1787                                "(block %llu)!\n", i, inode_bitmap);
1788                         return 0;
1789                 }
1790                 inode_table = ext4_inode_table(sb, gdp);
1791                 if (inode_table < first_block ||
1792                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1793                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1794                                "Inode table for group %u not in group "
1795                                "(block %llu)!\n", i, inode_table);
1796                         return 0;
1797                 }
1798                 ext4_lock_group(sb, i);
1799                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1800                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1801                                "Checksum for group %u failed (%u!=%u)\n",
1802                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1803                                gdp)), le16_to_cpu(gdp->bg_checksum));
1804                         if (!(sb->s_flags & MS_RDONLY)) {
1805                                 ext4_unlock_group(sb, i);
1806                                 return 0;
1807                         }
1808                 }
1809                 ext4_unlock_group(sb, i);
1810                 if (!flexbg_flag)
1811                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1812         }
1813
1814         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1815         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1816         return 1;
1817 }
1818
1819 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1820  * the superblock) which were deleted from all directories, but held open by
1821  * a process at the time of a crash.  We walk the list and try to delete these
1822  * inodes at recovery time (only with a read-write filesystem).
1823  *
1824  * In order to keep the orphan inode chain consistent during traversal (in
1825  * case of crash during recovery), we link each inode into the superblock
1826  * orphan list_head and handle it the same way as an inode deletion during
1827  * normal operation (which journals the operations for us).
1828  *
1829  * We only do an iget() and an iput() on each inode, which is very safe if we
1830  * accidentally point at an in-use or already deleted inode.  The worst that
1831  * can happen in this case is that we get a "bit already cleared" message from
1832  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1833  * e2fsck was run on this filesystem, and it must have already done the orphan
1834  * inode cleanup for us, so we can safely abort without any further action.
1835  */
1836 static void ext4_orphan_cleanup(struct super_block *sb,
1837                                 struct ext4_super_block *es)
1838 {
1839         unsigned int s_flags = sb->s_flags;
1840         int nr_orphans = 0, nr_truncates = 0;
1841 #ifdef CONFIG_QUOTA
1842         int i;
1843 #endif
1844         if (!es->s_last_orphan) {
1845                 jbd_debug(4, "no orphan inodes to clean up\n");
1846                 return;
1847         }
1848
1849         if (bdev_read_only(sb->s_bdev)) {
1850                 printk(KERN_ERR "EXT4-fs: write access "
1851                         "unavailable, skipping orphan cleanup.\n");
1852                 return;
1853         }
1854
1855         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1856                 if (es->s_last_orphan)
1857                         jbd_debug(1, "Errors on filesystem, "
1858                                   "clearing orphan list.\n");
1859                 es->s_last_orphan = 0;
1860                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1861                 return;
1862         }
1863
1864         if (s_flags & MS_RDONLY) {
1865                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1866                        sb->s_id);
1867                 sb->s_flags &= ~MS_RDONLY;
1868         }
1869 #ifdef CONFIG_QUOTA
1870         /* Needed for iput() to work correctly and not trash data */
1871         sb->s_flags |= MS_ACTIVE;
1872         /* Turn on quotas so that they are updated correctly */
1873         for (i = 0; i < MAXQUOTAS; i++) {
1874                 if (EXT4_SB(sb)->s_qf_names[i]) {
1875                         int ret = ext4_quota_on_mount(sb, i);
1876                         if (ret < 0)
1877                                 printk(KERN_ERR
1878                                         "EXT4-fs: Cannot turn on journaled "
1879                                         "quota: error %d\n", ret);
1880                 }
1881         }
1882 #endif
1883
1884         while (es->s_last_orphan) {
1885                 struct inode *inode;
1886
1887                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1888                 if (IS_ERR(inode)) {
1889                         es->s_last_orphan = 0;
1890                         break;
1891                 }
1892
1893                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1894                 vfs_dq_init(inode);
1895                 if (inode->i_nlink) {
1896                         printk(KERN_DEBUG
1897                                 "%s: truncating inode %lu to %lld bytes\n",
1898                                 __func__, inode->i_ino, inode->i_size);
1899                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1900                                   inode->i_ino, inode->i_size);
1901                         ext4_truncate(inode);
1902                         nr_truncates++;
1903                 } else {
1904                         printk(KERN_DEBUG
1905                                 "%s: deleting unreferenced inode %lu\n",
1906                                 __func__, inode->i_ino);
1907                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1908                                   inode->i_ino);
1909                         nr_orphans++;
1910                 }
1911                 iput(inode);  /* The delete magic happens here! */
1912         }
1913
1914 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1915
1916         if (nr_orphans)
1917                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1918                        sb->s_id, PLURAL(nr_orphans));
1919         if (nr_truncates)
1920                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1921                        sb->s_id, PLURAL(nr_truncates));
1922 #ifdef CONFIG_QUOTA
1923         /* Turn quotas off */
1924         for (i = 0; i < MAXQUOTAS; i++) {
1925                 if (sb_dqopt(sb)->files[i])
1926                         vfs_quota_off(sb, i, 0);
1927         }
1928 #endif
1929         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1930 }
1931
1932 /*
1933  * Maximal extent format file size.
1934  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1935  * extent format containers, within a sector_t, and within i_blocks
1936  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1937  * so that won't be a limiting factor.
1938  *
1939  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1940  */
1941 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1942 {
1943         loff_t res;
1944         loff_t upper_limit = MAX_LFS_FILESIZE;
1945
1946         /* small i_blocks in vfs inode? */
1947         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1948                 /*
1949                  * CONFIG_LBD is not enabled implies the inode
1950                  * i_block represent total blocks in 512 bytes
1951                  * 32 == size of vfs inode i_blocks * 8
1952                  */
1953                 upper_limit = (1LL << 32) - 1;
1954
1955                 /* total blocks in file system block size */
1956                 upper_limit >>= (blkbits - 9);
1957                 upper_limit <<= blkbits;
1958         }
1959
1960         /* 32-bit extent-start container, ee_block */
1961         res = 1LL << 32;
1962         res <<= blkbits;
1963         res -= 1;
1964
1965         /* Sanity check against vm- & vfs- imposed limits */
1966         if (res > upper_limit)
1967                 res = upper_limit;
1968
1969         return res;
1970 }
1971
1972 /*
1973  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1974  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1975  * We need to be 1 filesystem block less than the 2^48 sector limit.
1976  */
1977 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
1978 {
1979         loff_t res = EXT4_NDIR_BLOCKS;
1980         int meta_blocks;
1981         loff_t upper_limit;
1982         /* This is calculated to be the largest file size for a dense, block
1983          * mapped file such that the file's total number of 512-byte sectors,
1984          * including data and all indirect blocks, does not exceed (2^48 - 1).
1985          *
1986          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
1987          * number of 512-byte sectors of the file.
1988          */
1989
1990         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1991                 /*
1992                  * !has_huge_files or CONFIG_LBD not enabled implies that
1993                  * the inode i_block field represents total file blocks in
1994                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
1995                  */
1996                 upper_limit = (1LL << 32) - 1;
1997
1998                 /* total blocks in file system block size */
1999                 upper_limit >>= (bits - 9);
2000
2001         } else {
2002                 /*
2003                  * We use 48 bit ext4_inode i_blocks
2004                  * With EXT4_HUGE_FILE_FL set the i_blocks
2005                  * represent total number of blocks in
2006                  * file system block size
2007                  */
2008                 upper_limit = (1LL << 48) - 1;
2009
2010         }
2011
2012         /* indirect blocks */
2013         meta_blocks = 1;
2014         /* double indirect blocks */
2015         meta_blocks += 1 + (1LL << (bits-2));
2016         /* tripple indirect blocks */
2017         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2018
2019         upper_limit -= meta_blocks;
2020         upper_limit <<= bits;
2021
2022         res += 1LL << (bits-2);
2023         res += 1LL << (2*(bits-2));
2024         res += 1LL << (3*(bits-2));
2025         res <<= bits;
2026         if (res > upper_limit)
2027                 res = upper_limit;
2028
2029         if (res > MAX_LFS_FILESIZE)
2030                 res = MAX_LFS_FILESIZE;
2031
2032         return res;
2033 }
2034
2035 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2036                                    ext4_fsblk_t logical_sb_block, int nr)
2037 {
2038         struct ext4_sb_info *sbi = EXT4_SB(sb);
2039         ext4_group_t bg, first_meta_bg;
2040         int has_super = 0;
2041
2042         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2043
2044         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2045             nr < first_meta_bg)
2046                 return logical_sb_block + nr + 1;
2047         bg = sbi->s_desc_per_block * nr;
2048         if (ext4_bg_has_super(sb, bg))
2049                 has_super = 1;
2050
2051         return (has_super + ext4_group_first_block_no(sb, bg));
2052 }
2053
2054 /**
2055  * ext4_get_stripe_size: Get the stripe size.
2056  * @sbi: In memory super block info
2057  *
2058  * If we have specified it via mount option, then
2059  * use the mount option value. If the value specified at mount time is
2060  * greater than the blocks per group use the super block value.
2061  * If the super block value is greater than blocks per group return 0.
2062  * Allocator needs it be less than blocks per group.
2063  *
2064  */
2065 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2066 {
2067         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2068         unsigned long stripe_width =
2069                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2070
2071         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2072                 return sbi->s_stripe;
2073
2074         if (stripe_width <= sbi->s_blocks_per_group)
2075                 return stripe_width;
2076
2077         if (stride <= sbi->s_blocks_per_group)
2078                 return stride;
2079
2080         return 0;
2081 }
2082
2083 /* sysfs supprt */
2084
2085 struct ext4_attr {
2086         struct attribute attr;
2087         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2088         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2089                          const char *, size_t);
2090         int offset;
2091 };
2092
2093 static int parse_strtoul(const char *buf,
2094                 unsigned long max, unsigned long *value)
2095 {
2096         char *endp;
2097
2098         while (*buf && isspace(*buf))
2099                 buf++;
2100         *value = simple_strtoul(buf, &endp, 0);
2101         while (*endp && isspace(*endp))
2102                 endp++;
2103         if (*endp || *value > max)
2104                 return -EINVAL;
2105
2106         return 0;
2107 }
2108
2109 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2110                                               struct ext4_sb_info *sbi,
2111                                               char *buf)
2112 {
2113         return snprintf(buf, PAGE_SIZE, "%llu\n",
2114                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2115 }
2116
2117 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2118                                          struct ext4_sb_info *sbi, char *buf)
2119 {
2120         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2121
2122         return snprintf(buf, PAGE_SIZE, "%lu\n",
2123                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2124                          sbi->s_sectors_written_start) >> 1);
2125 }
2126
2127 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2128                                           struct ext4_sb_info *sbi, char *buf)
2129 {
2130         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2131
2132         return snprintf(buf, PAGE_SIZE, "%llu\n",
2133                         sbi->s_kbytes_written +
2134                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2135                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2136 }
2137
2138 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2139                                           struct ext4_sb_info *sbi,
2140                                           const char *buf, size_t count)
2141 {
2142         unsigned long t;
2143
2144         if (parse_strtoul(buf, 0x40000000, &t))
2145                 return -EINVAL;
2146
2147         if (!is_power_of_2(t))
2148                 return -EINVAL;
2149
2150         sbi->s_inode_readahead_blks = t;
2151         return count;
2152 }
2153
2154 static ssize_t sbi_ui_show(struct ext4_attr *a,
2155                            struct ext4_sb_info *sbi, char *buf)
2156 {
2157         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2158
2159         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2160 }
2161
2162 static ssize_t sbi_ui_store(struct ext4_attr *a,
2163                             struct ext4_sb_info *sbi,
2164                             const char *buf, size_t count)
2165 {
2166         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2167         unsigned long t;
2168
2169         if (parse_strtoul(buf, 0xffffffff, &t))
2170                 return -EINVAL;
2171         *ui = t;
2172         return count;
2173 }
2174
2175 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2176 static struct ext4_attr ext4_attr_##_name = {                   \
2177         .attr = {.name = __stringify(_name), .mode = _mode },   \
2178         .show   = _show,                                        \
2179         .store  = _store,                                       \
2180         .offset = offsetof(struct ext4_sb_info, _elname),       \
2181 }
2182 #define EXT4_ATTR(name, mode, show, store) \
2183 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2184
2185 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2186 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2187 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2188         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2189 #define ATTR_LIST(name) &ext4_attr_##name.attr
2190
2191 EXT4_RO_ATTR(delayed_allocation_blocks);
2192 EXT4_RO_ATTR(session_write_kbytes);
2193 EXT4_RO_ATTR(lifetime_write_kbytes);
2194 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2195                  inode_readahead_blks_store, s_inode_readahead_blks);
2196 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2197 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2198 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2199 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2200 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2201 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2202
2203 static struct attribute *ext4_attrs[] = {
2204         ATTR_LIST(delayed_allocation_blocks),
2205         ATTR_LIST(session_write_kbytes),
2206         ATTR_LIST(lifetime_write_kbytes),
2207         ATTR_LIST(inode_readahead_blks),
2208         ATTR_LIST(mb_stats),
2209         ATTR_LIST(mb_max_to_scan),
2210         ATTR_LIST(mb_min_to_scan),
2211         ATTR_LIST(mb_order2_req),
2212         ATTR_LIST(mb_stream_req),
2213         ATTR_LIST(mb_group_prealloc),
2214         NULL,
2215 };
2216
2217 static ssize_t ext4_attr_show(struct kobject *kobj,
2218                               struct attribute *attr, char *buf)
2219 {
2220         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2221                                                 s_kobj);
2222         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2223
2224         return a->show ? a->show(a, sbi, buf) : 0;
2225 }
2226
2227 static ssize_t ext4_attr_store(struct kobject *kobj,
2228                                struct attribute *attr,
2229                                const char *buf, size_t len)
2230 {
2231         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2232                                                 s_kobj);
2233         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2234
2235         return a->store ? a->store(a, sbi, buf, len) : 0;
2236 }
2237
2238 static void ext4_sb_release(struct kobject *kobj)
2239 {
2240         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2241                                                 s_kobj);
2242         complete(&sbi->s_kobj_unregister);
2243 }
2244
2245
2246 static struct sysfs_ops ext4_attr_ops = {
2247         .show   = ext4_attr_show,
2248         .store  = ext4_attr_store,
2249 };
2250
2251 static struct kobj_type ext4_ktype = {
2252         .default_attrs  = ext4_attrs,
2253         .sysfs_ops      = &ext4_attr_ops,
2254         .release        = ext4_sb_release,
2255 };
2256
2257 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2258                                 __releases(kernel_lock)
2259                                 __acquires(kernel_lock)
2260 {
2261         struct buffer_head *bh;
2262         struct ext4_super_block *es = NULL;
2263         struct ext4_sb_info *sbi;
2264         ext4_fsblk_t block;
2265         ext4_fsblk_t sb_block = get_sb_block(&data);
2266         ext4_fsblk_t logical_sb_block;
2267         unsigned long offset = 0;
2268         unsigned long journal_devnum = 0;
2269         unsigned long def_mount_opts;
2270         struct inode *root;
2271         char *cp;
2272         const char *descr;
2273         int ret = -EINVAL;
2274         int blocksize;
2275         unsigned int db_count;
2276         unsigned int i;
2277         int needs_recovery, has_huge_files;
2278         int features;
2279         __u64 blocks_count;
2280         int err;
2281         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2282
2283         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2284         if (!sbi)
2285                 return -ENOMEM;
2286
2287         sbi->s_blockgroup_lock =
2288                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2289         if (!sbi->s_blockgroup_lock) {
2290                 kfree(sbi);
2291                 return -ENOMEM;
2292         }
2293         sb->s_fs_info = sbi;
2294         sbi->s_mount_opt = 0;
2295         sbi->s_resuid = EXT4_DEF_RESUID;
2296         sbi->s_resgid = EXT4_DEF_RESGID;
2297         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2298         sbi->s_sb_block = sb_block;
2299         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2300                                                       sectors[1]);
2301
2302         unlock_kernel();
2303
2304         /* Cleanup superblock name */
2305         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2306                 *cp = '!';
2307
2308         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2309         if (!blocksize) {
2310                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
2311                 goto out_fail;
2312         }
2313
2314         /*
2315          * The ext4 superblock will not be buffer aligned for other than 1kB
2316          * block sizes.  We need to calculate the offset from buffer start.
2317          */
2318         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2319                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2320                 offset = do_div(logical_sb_block, blocksize);
2321         } else {
2322                 logical_sb_block = sb_block;
2323         }
2324
2325         if (!(bh = sb_bread(sb, logical_sb_block))) {
2326                 printk(KERN_ERR "EXT4-fs: unable to read superblock\n");
2327                 goto out_fail;
2328         }
2329         /*
2330          * Note: s_es must be initialized as soon as possible because
2331          *       some ext4 macro-instructions depend on its value
2332          */
2333         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2334         sbi->s_es = es;
2335         sb->s_magic = le16_to_cpu(es->s_magic);
2336         if (sb->s_magic != EXT4_SUPER_MAGIC)
2337                 goto cantfind_ext4;
2338         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2339
2340         /* Set defaults before we parse the mount options */
2341         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2342         if (def_mount_opts & EXT4_DEFM_DEBUG)
2343                 set_opt(sbi->s_mount_opt, DEBUG);
2344         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2345                 set_opt(sbi->s_mount_opt, GRPID);
2346         if (def_mount_opts & EXT4_DEFM_UID16)
2347                 set_opt(sbi->s_mount_opt, NO_UID32);
2348 #ifdef CONFIG_EXT4_FS_XATTR
2349         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2350                 set_opt(sbi->s_mount_opt, XATTR_USER);
2351 #endif
2352 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2353         if (def_mount_opts & EXT4_DEFM_ACL)
2354                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2355 #endif
2356         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2357                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2358         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2359                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2360         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2361                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2362
2363         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2364                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2365         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2366                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2367         else
2368                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2369
2370         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2371         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2372         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2373         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2374         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2375         sbi->s_mb_history_max = default_mb_history_length;
2376
2377         set_opt(sbi->s_mount_opt, BARRIER);
2378
2379         /*
2380          * enable delayed allocation by default
2381          * Use -o nodelalloc to turn it off
2382          */
2383         set_opt(sbi->s_mount_opt, DELALLOC);
2384
2385         if (!parse_options((char *) data, sb, &journal_devnum,
2386                            &journal_ioprio, NULL, 0))
2387                 goto failed_mount;
2388
2389         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2390                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2391
2392         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2393             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2394              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2395              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2396                 printk(KERN_WARNING
2397                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2398                        "running e2fsck is recommended\n");
2399
2400         /*
2401          * Check feature flags regardless of the revision level, since we
2402          * previously didn't change the revision level when setting the flags,
2403          * so there is a chance incompat flags are set on a rev 0 filesystem.
2404          */
2405         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2406         if (features) {
2407                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2408                        "unsupported optional features (%x).\n", sb->s_id,
2409                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2410                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2411                 goto failed_mount;
2412         }
2413         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2414         if (!(sb->s_flags & MS_RDONLY) && features) {
2415                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2416                        "unsupported optional features (%x).\n", sb->s_id,
2417                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2418                         ~EXT4_FEATURE_RO_COMPAT_SUPP));
2419                 goto failed_mount;
2420         }
2421         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2422                                     EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2423         if (has_huge_files) {
2424                 /*
2425                  * Large file size enabled file system can only be
2426                  * mount if kernel is build with CONFIG_LBD
2427                  */
2428                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2429                                 !(sb->s_flags & MS_RDONLY)) {
2430                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2431                                         "files cannot be mounted read-write "
2432                                         "without CONFIG_LBD.\n", sb->s_id);
2433                         goto failed_mount;
2434                 }
2435         }
2436         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2437
2438         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2439             blocksize > EXT4_MAX_BLOCK_SIZE) {
2440                 printk(KERN_ERR
2441                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2442                        blocksize, sb->s_id);
2443                 goto failed_mount;
2444         }
2445
2446         if (sb->s_blocksize != blocksize) {
2447                 /* Validate the filesystem blocksize */
2448                 if (!sb_set_blocksize(sb, blocksize)) {
2449                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2450                                         blocksize);
2451                         goto failed_mount;
2452                 }
2453
2454                 brelse(bh);
2455                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2456                 offset = do_div(logical_sb_block, blocksize);
2457                 bh = sb_bread(sb, logical_sb_block);
2458                 if (!bh) {
2459                         printk(KERN_ERR
2460                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2461                         goto failed_mount;
2462                 }
2463                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2464                 sbi->s_es = es;
2465                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2466                         printk(KERN_ERR
2467                                "EXT4-fs: Magic mismatch, very weird !\n");
2468                         goto failed_mount;
2469                 }
2470         }
2471
2472         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2473                                                       has_huge_files);
2474         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2475
2476         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2477                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2478                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2479         } else {
2480                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2481                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2482                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2483                     (!is_power_of_2(sbi->s_inode_size)) ||
2484                     (sbi->s_inode_size > blocksize)) {
2485                         printk(KERN_ERR
2486                                "EXT4-fs: unsupported inode size: %d\n",
2487                                sbi->s_inode_size);
2488                         goto failed_mount;
2489                 }
2490                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2491                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2492         }
2493
2494         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2495         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2496                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2497                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2498                     !is_power_of_2(sbi->s_desc_size)) {
2499                         printk(KERN_ERR
2500                                "EXT4-fs: unsupported descriptor size %lu\n",
2501                                sbi->s_desc_size);
2502                         goto failed_mount;
2503                 }
2504         } else
2505                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2506
2507         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2508         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2509         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2510                 goto cantfind_ext4;
2511
2512         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2513         if (sbi->s_inodes_per_block == 0)
2514                 goto cantfind_ext4;
2515         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2516                                         sbi->s_inodes_per_block;
2517         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2518         sbi->s_sbh = bh;
2519         sbi->s_mount_state = le16_to_cpu(es->s_state);
2520         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2521         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2522
2523         for (i = 0; i < 4; i++)
2524                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2525         sbi->s_def_hash_version = es->s_def_hash_version;
2526         i = le32_to_cpu(es->s_flags);
2527         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2528                 sbi->s_hash_unsigned = 3;
2529         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2530 #ifdef __CHAR_UNSIGNED__
2531                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2532                 sbi->s_hash_unsigned = 3;
2533 #else
2534                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2535 #endif
2536                 sb->s_dirt = 1;
2537         }
2538
2539         if (sbi->s_blocks_per_group > blocksize * 8) {
2540                 printk(KERN_ERR
2541                        "EXT4-fs: #blocks per group too big: %lu\n",
2542                        sbi->s_blocks_per_group);
2543                 goto failed_mount;
2544         }
2545         if (sbi->s_inodes_per_group > blocksize * 8) {
2546                 printk(KERN_ERR
2547                        "EXT4-fs: #inodes per group too big: %lu\n",
2548                        sbi->s_inodes_per_group);
2549                 goto failed_mount;
2550         }
2551
2552         if (ext4_blocks_count(es) >
2553                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2554                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2555                         " too large to mount safely\n", sb->s_id);
2556                 if (sizeof(sector_t) < 8)
2557                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2558                                         "enabled\n");
2559                 goto failed_mount;
2560         }
2561
2562         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2563                 goto cantfind_ext4;
2564
2565         /* check blocks count against device size */
2566         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2567         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2568                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu "
2569                        "exceeds size of device (%llu blocks)\n",
2570                        ext4_blocks_count(es), blocks_count);
2571                 goto failed_mount;
2572         }
2573
2574         /*
2575          * It makes no sense for the first data block to be beyond the end
2576          * of the filesystem.
2577          */
2578         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2579                 printk(KERN_WARNING "EXT4-fs: bad geometry: first data"
2580                        "block %u is beyond end of filesystem (%llu)\n",
2581                        le32_to_cpu(es->s_first_data_block),
2582                        ext4_blocks_count(es));
2583                 goto failed_mount;
2584         }
2585         blocks_count = (ext4_blocks_count(es) -
2586                         le32_to_cpu(es->s_first_data_block) +
2587                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2588         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2589         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2590                 printk(KERN_WARNING "EXT4-fs: groups count too large: %u "
2591                        "(block count %llu, first data block %u, "
2592                        "blocks per group %lu)\n", sbi->s_groups_count,
2593                        ext4_blocks_count(es),
2594                        le32_to_cpu(es->s_first_data_block),
2595                        EXT4_BLOCKS_PER_GROUP(sb));
2596                 goto failed_mount;
2597         }
2598         sbi->s_groups_count = blocks_count;
2599         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2600                    EXT4_DESC_PER_BLOCK(sb);
2601         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2602                                     GFP_KERNEL);
2603         if (sbi->s_group_desc == NULL) {
2604                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
2605                 goto failed_mount;
2606         }
2607
2608 #ifdef CONFIG_PROC_FS
2609         if (ext4_proc_root)
2610                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2611 #endif
2612
2613         bgl_lock_init(sbi->s_blockgroup_lock);
2614
2615         for (i = 0; i < db_count; i++) {
2616                 block = descriptor_loc(sb, logical_sb_block, i);
2617                 sbi->s_group_desc[i] = sb_bread(sb, block);
2618                 if (!sbi->s_group_desc[i]) {
2619                         printk(KERN_ERR "EXT4-fs: "
2620                                "can't read group descriptor %d\n", i);
2621                         db_count = i;
2622                         goto failed_mount2;
2623                 }
2624         }
2625         if (!ext4_check_descriptors(sb)) {
2626                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2627                 goto failed_mount2;
2628         }
2629         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2630                 if (!ext4_fill_flex_info(sb)) {
2631                         printk(KERN_ERR
2632                                "EXT4-fs: unable to initialize "
2633                                "flex_bg meta info!\n");
2634                         goto failed_mount2;
2635                 }
2636
2637         sbi->s_gdb_count = db_count;
2638         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2639         spin_lock_init(&sbi->s_next_gen_lock);
2640
2641         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2642                         ext4_count_free_blocks(sb));
2643         if (!err) {
2644                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2645                                 ext4_count_free_inodes(sb));
2646         }
2647         if (!err) {
2648                 err = percpu_counter_init(&sbi->s_dirs_counter,
2649                                 ext4_count_dirs(sb));
2650         }
2651         if (!err) {
2652                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2653         }
2654         if (err) {
2655                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2656                 goto failed_mount3;
2657         }
2658
2659         sbi->s_stripe = ext4_get_stripe_size(sbi);
2660
2661         /*
2662          * set up enough so that it can read an inode
2663          */
2664         if (!test_opt(sb, NOLOAD) &&
2665             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2666                 sb->s_op = &ext4_sops;
2667         else
2668                 sb->s_op = &ext4_nojournal_sops;
2669         sb->s_export_op = &ext4_export_ops;
2670         sb->s_xattr = ext4_xattr_handlers;
2671 #ifdef CONFIG_QUOTA
2672         sb->s_qcop = &ext4_qctl_operations;
2673         sb->dq_op = &ext4_quota_operations;
2674 #endif
2675         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2676         mutex_init(&sbi->s_orphan_lock);
2677         mutex_init(&sbi->s_resize_lock);
2678
2679         sb->s_root = NULL;
2680
2681         needs_recovery = (es->s_last_orphan != 0 ||
2682                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2683                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2684
2685         /*
2686          * The first inode we look at is the journal inode.  Don't try
2687          * root first: it may be modified in the journal!
2688          */
2689         if (!test_opt(sb, NOLOAD) &&
2690             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2691                 if (ext4_load_journal(sb, es, journal_devnum))
2692                         goto failed_mount3;
2693                 if (!(sb->s_flags & MS_RDONLY) &&
2694                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2695                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2696                                "ext4_fill_super: Journal transaction "
2697                                "%u is corrupt\n", sb->s_id,
2698                                EXT4_SB(sb)->s_journal->j_failed_commit);
2699                         if (test_opt(sb, ERRORS_RO)) {
2700                                 printk(KERN_CRIT
2701                                        "Mounting filesystem read-only\n");
2702                                 sb->s_flags |= MS_RDONLY;
2703                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2704                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2705                         }
2706                         if (test_opt(sb, ERRORS_PANIC)) {
2707                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2708                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2709                                 ext4_commit_super(sb, 1);
2710                                 goto failed_mount4;
2711                         }
2712                 }
2713         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2714               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2715                 printk(KERN_ERR "EXT4-fs: required journal recovery "
2716                        "suppressed and not mounted read-only\n");
2717                 goto failed_mount4;
2718         } else {
2719                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2720                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2721                 sbi->s_journal = NULL;
2722                 needs_recovery = 0;
2723                 goto no_journal;
2724         }
2725
2726         if (ext4_blocks_count(es) > 0xffffffffULL &&
2727             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2728                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2729                 printk(KERN_ERR "EXT4-fs: Failed to set 64-bit journal feature\n");
2730                 goto failed_mount4;
2731         }
2732
2733         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2734                 jbd2_journal_set_features(sbi->s_journal,
2735                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2736                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2737         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2738                 jbd2_journal_set_features(sbi->s_journal,
2739                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2740                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2741                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2742         } else {
2743                 jbd2_journal_clear_features(sbi->s_journal,
2744                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2745                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2746         }
2747
2748         /* We have now updated the journal if required, so we can
2749          * validate the data journaling mode. */
2750         switch (test_opt(sb, DATA_FLAGS)) {
2751         case 0:
2752                 /* No mode set, assume a default based on the journal
2753                  * capabilities: ORDERED_DATA if the journal can
2754                  * cope, else JOURNAL_DATA
2755                  */
2756                 if (jbd2_journal_check_available_features
2757                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2758                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2759                 else
2760                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2761                 break;
2762
2763         case EXT4_MOUNT_ORDERED_DATA:
2764         case EXT4_MOUNT_WRITEBACK_DATA:
2765                 if (!jbd2_journal_check_available_features
2766                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2767                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2768                                "requested data journaling mode\n");
2769                         goto failed_mount4;
2770                 }
2771         default:
2772                 break;
2773         }
2774         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2775
2776 no_journal:
2777
2778         if (test_opt(sb, NOBH)) {
2779                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2780                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2781                                 "its supported only with writeback mode\n");
2782                         clear_opt(sbi->s_mount_opt, NOBH);
2783                 }
2784         }
2785         /*
2786          * The jbd2_journal_load will have done any necessary log recovery,
2787          * so we can safely mount the rest of the filesystem now.
2788          */
2789
2790         root = ext4_iget(sb, EXT4_ROOT_INO);
2791         if (IS_ERR(root)) {
2792                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2793                 ret = PTR_ERR(root);
2794                 goto failed_mount4;
2795         }
2796         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2797                 iput(root);
2798                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2799                 goto failed_mount4;
2800         }
2801         sb->s_root = d_alloc_root(root);
2802         if (!sb->s_root) {
2803                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2804                 iput(root);
2805                 ret = -ENOMEM;
2806                 goto failed_mount4;
2807         }
2808
2809         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2810
2811         /* determine the minimum size of new large inodes, if present */
2812         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2813                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2814                                                      EXT4_GOOD_OLD_INODE_SIZE;
2815                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2816                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2817                         if (sbi->s_want_extra_isize <
2818                             le16_to_cpu(es->s_want_extra_isize))
2819                                 sbi->s_want_extra_isize =
2820                                         le16_to_cpu(es->s_want_extra_isize);
2821                         if (sbi->s_want_extra_isize <
2822                             le16_to_cpu(es->s_min_extra_isize))
2823                                 sbi->s_want_extra_isize =
2824                                         le16_to_cpu(es->s_min_extra_isize);
2825                 }
2826         }
2827         /* Check if enough inode space is available */
2828         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2829                                                         sbi->s_inode_size) {
2830                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2831                                                        EXT4_GOOD_OLD_INODE_SIZE;
2832                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2833                         "available.\n");
2834         }
2835
2836         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2837                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2838                                 "requested data journaling mode\n");
2839                 clear_opt(sbi->s_mount_opt, DELALLOC);
2840         } else if (test_opt(sb, DELALLOC))
2841                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2842
2843         err = ext4_setup_system_zone(sb);
2844         if (err) {
2845                 printk(KERN_ERR "EXT4-fs: failed to initialize system "
2846                        "zone (%d)\n", err);
2847                 goto failed_mount4;
2848         }
2849
2850         ext4_ext_init(sb);
2851         err = ext4_mb_init(sb, needs_recovery);
2852         if (err) {
2853                 printk(KERN_ERR "EXT4-fs: failed to initalize mballoc (%d)\n",
2854                        err);
2855                 goto failed_mount4;
2856         }
2857
2858         sbi->s_kobj.kset = ext4_kset;
2859         init_completion(&sbi->s_kobj_unregister);
2860         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2861                                    "%s", sb->s_id);
2862         if (err) {
2863                 ext4_mb_release(sb);
2864                 ext4_ext_release(sb);
2865                 goto failed_mount4;
2866         };
2867
2868         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2869         ext4_orphan_cleanup(sb, es);
2870         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2871         if (needs_recovery) {
2872                 printk(KERN_INFO "EXT4-fs: recovery complete.\n");
2873                 ext4_mark_recovery_complete(sb, es);
2874         }
2875         if (EXT4_SB(sb)->s_journal) {
2876                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2877                         descr = " journalled data mode";
2878                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2879                         descr = " ordered data mode";
2880                 else
2881                         descr = " writeback data mode";
2882         } else
2883                 descr = "out journal";
2884
2885         printk(KERN_INFO "EXT4-fs: mounted filesystem %s with%s\n",
2886                sb->s_id, descr);
2887
2888         lock_kernel();
2889         return 0;
2890
2891 cantfind_ext4:
2892         if (!silent)
2893                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2894                        sb->s_id);
2895         goto failed_mount;
2896
2897 failed_mount4:
2898         printk(KERN_ERR "EXT4-fs (device %s): mount failed\n", sb->s_id);
2899         ext4_release_system_zone(sb);
2900         if (sbi->s_journal) {
2901                 jbd2_journal_destroy(sbi->s_journal);
2902                 sbi->s_journal = NULL;
2903         }
2904 failed_mount3:
2905         if (sbi->s_flex_groups) {
2906                 if (is_vmalloc_addr(sbi->s_flex_groups))
2907                         vfree(sbi->s_flex_groups);
2908                 else
2909                         kfree(sbi->s_flex_groups);
2910         }
2911         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2912         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2913         percpu_counter_destroy(&sbi->s_dirs_counter);
2914         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2915 failed_mount2:
2916         for (i = 0; i < db_count; i++)
2917                 brelse(sbi->s_group_desc[i]);
2918         kfree(sbi->s_group_desc);
2919 failed_mount:
2920         if (sbi->s_proc) {
2921                 remove_proc_entry(sb->s_id, ext4_proc_root);
2922         }
2923 #ifdef CONFIG_QUOTA
2924         for (i = 0; i < MAXQUOTAS; i++)
2925                 kfree(sbi->s_qf_names[i]);
2926 #endif
2927         ext4_blkdev_remove(sbi);
2928         brelse(bh);
2929 out_fail:
2930         sb->s_fs_info = NULL;
2931         kfree(sbi->s_blockgroup_lock);
2932         kfree(sbi);
2933         lock_kernel();
2934         return ret;
2935 }
2936
2937 /*
2938  * Setup any per-fs journal parameters now.  We'll do this both on
2939  * initial mount, once the journal has been initialised but before we've
2940  * done any recovery; and again on any subsequent remount.
2941  */
2942 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2943 {
2944         struct ext4_sb_info *sbi = EXT4_SB(sb);
2945
2946         journal->j_commit_interval = sbi->s_commit_interval;
2947         journal->j_min_batch_time = sbi->s_min_batch_time;
2948         journal->j_max_batch_time = sbi->s_max_batch_time;
2949
2950         spin_lock(&journal->j_state_lock);
2951         if (test_opt(sb, BARRIER))
2952                 journal->j_flags |= JBD2_BARRIER;
2953         else
2954                 journal->j_flags &= ~JBD2_BARRIER;
2955         if (test_opt(sb, DATA_ERR_ABORT))
2956                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
2957         else
2958                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
2959         spin_unlock(&journal->j_state_lock);
2960 }
2961
2962 static journal_t *ext4_get_journal(struct super_block *sb,
2963                                    unsigned int journal_inum)
2964 {
2965         struct inode *journal_inode;
2966         journal_t *journal;
2967
2968         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2969
2970         /* First, test for the existence of a valid inode on disk.  Bad
2971          * things happen if we iget() an unused inode, as the subsequent
2972          * iput() will try to delete it. */
2973
2974         journal_inode = ext4_iget(sb, journal_inum);
2975         if (IS_ERR(journal_inode)) {
2976                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2977                 return NULL;
2978         }
2979         if (!journal_inode->i_nlink) {
2980                 make_bad_inode(journal_inode);
2981                 iput(journal_inode);
2982                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2983                 return NULL;
2984         }
2985
2986         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
2987                   journal_inode, journal_inode->i_size);
2988         if (!S_ISREG(journal_inode->i_mode)) {
2989                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2990                 iput(journal_inode);
2991                 return NULL;
2992         }
2993
2994         journal = jbd2_journal_init_inode(journal_inode);
2995         if (!journal) {
2996                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2997                 iput(journal_inode);
2998                 return NULL;
2999         }
3000         journal->j_private = sb;
3001         ext4_init_journal_params(sb, journal);
3002         return journal;
3003 }
3004
3005 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3006                                        dev_t j_dev)
3007 {
3008         struct buffer_head *bh;
3009         journal_t *journal;
3010         ext4_fsblk_t start;
3011         ext4_fsblk_t len;
3012         int hblock, blocksize;
3013         ext4_fsblk_t sb_block;
3014         unsigned long offset;
3015         struct ext4_super_block *es;
3016         struct block_device *bdev;
3017
3018         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3019
3020         bdev = ext4_blkdev_get(j_dev);
3021         if (bdev == NULL)
3022                 return NULL;
3023
3024         if (bd_claim(bdev, sb)) {
3025                 printk(KERN_ERR
3026                         "EXT4-fs: failed to claim external journal device.\n");
3027                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3028                 return NULL;
3029         }
3030
3031         blocksize = sb->s_blocksize;
3032         hblock = bdev_hardsect_size(bdev);
3033         if (blocksize < hblock) {
3034                 printk(KERN_ERR
3035                         "EXT4-fs: blocksize too small for journal device.\n");
3036                 goto out_bdev;
3037         }
3038
3039         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3040         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3041         set_blocksize(bdev, blocksize);
3042         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3043                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
3044                        "external journal\n");
3045                 goto out_bdev;
3046         }
3047
3048         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3049         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3050             !(le32_to_cpu(es->s_feature_incompat) &
3051               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3052                 printk(KERN_ERR "EXT4-fs: external journal has "
3053                                         "bad superblock\n");
3054                 brelse(bh);
3055                 goto out_bdev;
3056         }
3057
3058         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3059                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
3060                 brelse(bh);
3061                 goto out_bdev;
3062         }
3063
3064         len = ext4_blocks_count(es);
3065         start = sb_block + 1;
3066         brelse(bh);     /* we're done with the superblock */
3067
3068         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3069                                         start, len, blocksize);
3070         if (!journal) {
3071                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
3072                 goto out_bdev;
3073         }
3074         journal->j_private = sb;
3075         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3076         wait_on_buffer(journal->j_sb_buffer);
3077         if (!buffer_uptodate(journal->j_sb_buffer)) {
3078                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
3079                 goto out_journal;
3080         }
3081         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3082                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
3083                                         "user (unsupported) - %d\n",
3084                         be32_to_cpu(journal->j_superblock->s_nr_users));
3085                 goto out_journal;
3086         }
3087         EXT4_SB(sb)->journal_bdev = bdev;
3088         ext4_init_journal_params(sb, journal);
3089         return journal;
3090
3091 out_journal:
3092         jbd2_journal_destroy(journal);
3093 out_bdev:
3094         ext4_blkdev_put(bdev);
3095         return NULL;
3096 }
3097
3098 static int ext4_load_journal(struct super_block *sb,
3099                              struct ext4_super_block *es,
3100                              unsigned long journal_devnum)
3101 {
3102         journal_t *journal;
3103         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3104         dev_t journal_dev;
3105         int err = 0;
3106         int really_read_only;
3107
3108         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3109
3110         if (journal_devnum &&
3111             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3112                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
3113                         "numbers have changed\n");
3114                 journal_dev = new_decode_dev(journal_devnum);
3115         } else
3116                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3117
3118         really_read_only = bdev_read_only(sb->s_bdev);
3119
3120         /*
3121          * Are we loading a blank journal or performing recovery after a
3122          * crash?  For recovery, we need to check in advance whether we
3123          * can get read-write access to the device.
3124          */
3125         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3126                 if (sb->s_flags & MS_RDONLY) {
3127                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
3128                                         "required on readonly filesystem.\n");
3129                         if (really_read_only) {
3130                                 printk(KERN_ERR "EXT4-fs: write access "
3131                                         "unavailable, cannot proceed.\n");
3132                                 return -EROFS;
3133                         }
3134                         printk(KERN_INFO "EXT4-fs: write access will "
3135                                "be enabled during recovery.\n");
3136                 }
3137         }
3138
3139         if (journal_inum && journal_dev) {
3140                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
3141                        "and inode journals!\n");
3142                 return -EINVAL;
3143         }
3144
3145         if (journal_inum) {
3146                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3147                         return -EINVAL;
3148         } else {
3149                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3150                         return -EINVAL;
3151         }
3152
3153         if (journal->j_flags & JBD2_BARRIER)
3154                 printk(KERN_INFO "EXT4-fs: barriers enabled\n");
3155         else
3156                 printk(KERN_INFO "EXT4-fs: barriers disabled\n");
3157
3158         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3159                 err = jbd2_journal_update_format(journal);
3160                 if (err)  {
3161                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
3162                         jbd2_journal_destroy(journal);
3163                         return err;
3164                 }
3165         }
3166
3167         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3168                 err = jbd2_journal_wipe(journal, !really_read_only);
3169         if (!err)
3170                 err = jbd2_journal_load(journal);
3171
3172         if (err) {
3173                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
3174                 jbd2_journal_destroy(journal);
3175                 return err;
3176         }
3177
3178         EXT4_SB(sb)->s_journal = journal;
3179         ext4_clear_journal_err(sb, es);
3180
3181         if (journal_devnum &&
3182             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3183                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3184
3185                 /* Make sure we flush the recovery flag to disk. */
3186                 ext4_commit_super(sb, 1);
3187         }
3188
3189         return 0;
3190 }
3191
3192 static int ext4_commit_super(struct super_block *sb, int sync)
3193 {
3194         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3195         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3196         int error = 0;
3197
3198         if (!sbh)
3199                 return error;
3200         if (buffer_write_io_error(sbh)) {
3201                 /*
3202                  * Oh, dear.  A previous attempt to write the
3203                  * superblock failed.  This could happen because the
3204                  * USB device was yanked out.  Or it could happen to
3205                  * be a transient write error and maybe the block will
3206                  * be remapped.  Nothing we can do but to retry the
3207                  * write and hope for the best.
3208                  */
3209                 printk(KERN_ERR "EXT4-fs: previous I/O error to "
3210                        "superblock detected for %s.\n", sb->s_id);
3211                 clear_buffer_write_io_error(sbh);
3212                 set_buffer_uptodate(sbh);
3213         }
3214         es->s_wtime = cpu_to_le32(get_seconds());
3215         es->s_kbytes_written =
3216                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3217                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3218                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3219         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3220                                         &EXT4_SB(sb)->s_freeblocks_counter));
3221         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3222                                         &EXT4_SB(sb)->s_freeinodes_counter));
3223         sb->s_dirt = 0;
3224         BUFFER_TRACE(sbh, "marking dirty");
3225         mark_buffer_dirty(sbh);
3226         if (sync) {
3227                 error = sync_dirty_buffer(sbh);
3228                 if (error)
3229                         return error;
3230
3231                 error = buffer_write_io_error(sbh);
3232                 if (error) {
3233                         printk(KERN_ERR "EXT4-fs: I/O error while writing "
3234                                "superblock for %s.\n", sb->s_id);
3235                         clear_buffer_write_io_error(sbh);
3236                         set_buffer_uptodate(sbh);
3237                 }
3238         }
3239         return error;
3240 }
3241
3242 /*
3243  * Have we just finished recovery?  If so, and if we are mounting (or
3244  * remounting) the filesystem readonly, then we will end up with a
3245  * consistent fs on disk.  Record that fact.
3246  */
3247 static void ext4_mark_recovery_complete(struct super_block *sb,
3248                                         struct ext4_super_block *es)
3249 {
3250         journal_t *journal = EXT4_SB(sb)->s_journal;
3251
3252         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3253                 BUG_ON(journal != NULL);
3254                 return;
3255         }
3256         jbd2_journal_lock_updates(journal);
3257         if (jbd2_journal_flush(journal) < 0)
3258                 goto out;
3259
3260         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3261             sb->s_flags & MS_RDONLY) {
3262                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3263                 ext4_commit_super(sb, 1);
3264         }
3265
3266 out:
3267         jbd2_journal_unlock_updates(journal);
3268 }
3269
3270 /*
3271  * If we are mounting (or read-write remounting) a filesystem whose journal
3272  * has recorded an error from a previous lifetime, move that error to the
3273  * main filesystem now.
3274  */
3275 static void ext4_clear_journal_err(struct super_block *sb,
3276                                    struct ext4_super_block *es)
3277 {
3278         journal_t *journal;
3279         int j_errno;
3280         const char *errstr;
3281
3282         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3283
3284         journal = EXT4_SB(sb)->s_journal;
3285
3286         /*
3287          * Now check for any error status which may have been recorded in the
3288          * journal by a prior ext4_error() or ext4_abort()
3289          */
3290
3291         j_errno = jbd2_journal_errno(journal);
3292         if (j_errno) {
3293                 char nbuf[16];
3294
3295                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3296                 ext4_warning(sb, __func__, "Filesystem error recorded "
3297                              "from previous mount: %s", errstr);
3298                 ext4_warning(sb, __func__, "Marking fs in need of "
3299                              "filesystem check.");
3300
3301                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3302                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3303                 ext4_commit_super(sb, 1);
3304
3305                 jbd2_journal_clear_err(journal);
3306         }
3307 }
3308
3309 /*
3310  * Force the running and committing transactions to commit,
3311  * and wait on the commit.
3312  */
3313 int ext4_force_commit(struct super_block *sb)
3314 {
3315         journal_t *journal;
3316         int ret = 0;
3317
3318         if (sb->s_flags & MS_RDONLY)
3319                 return 0;
3320
3321         journal = EXT4_SB(sb)->s_journal;
3322         if (journal)
3323                 ret = ext4_journal_force_commit(journal);
3324
3325         return ret;
3326 }
3327
3328 static void ext4_write_super(struct super_block *sb)
3329 {
3330         ext4_commit_super(sb, 1);
3331 }
3332
3333 static int ext4_sync_fs(struct super_block *sb, int wait)
3334 {
3335         int ret = 0;
3336         tid_t target;
3337
3338         trace_mark(ext4_sync_fs, "dev %s wait %d", sb->s_id, wait);
3339         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
3340                 if (wait)
3341                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
3342         }
3343         return ret;
3344 }
3345
3346 /*
3347  * LVM calls this function before a (read-only) snapshot is created.  This
3348  * gives us a chance to flush the journal completely and mark the fs clean.
3349  */
3350 static int ext4_freeze(struct super_block *sb)
3351 {
3352         int error = 0;
3353         journal_t *journal;
3354
3355         if (sb->s_flags & MS_RDONLY)
3356                 return 0;
3357
3358         journal = EXT4_SB(sb)->s_journal;
3359
3360         /* Now we set up the journal barrier. */
3361         jbd2_journal_lock_updates(journal);
3362
3363         /*
3364          * Don't clear the needs_recovery flag if we failed to flush
3365          * the journal.
3366          */
3367         error = jbd2_journal_flush(journal);
3368         if (error < 0) {
3369         out:
3370                 jbd2_journal_unlock_updates(journal);
3371                 return error;
3372         }
3373
3374         /* Journal blocked and flushed, clear needs_recovery flag. */
3375         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3376         error = ext4_commit_super(sb, 1);
3377         if (error)
3378                 goto out;
3379         return 0;
3380 }
3381
3382 /*
3383  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3384  * flag here, even though the filesystem is not technically dirty yet.
3385  */
3386 static int ext4_unfreeze(struct super_block *sb)
3387 {
3388         if (sb->s_flags & MS_RDONLY)
3389                 return 0;
3390
3391         lock_super(sb);
3392         /* Reset the needs_recovery flag before the fs is unlocked. */
3393         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3394         ext4_commit_super(sb, 1);
3395         unlock_super(sb);
3396         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3397         return 0;
3398 }
3399
3400 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3401 {
3402         struct ext4_super_block *es;
3403         struct ext4_sb_info *sbi = EXT4_SB(sb);
3404         ext4_fsblk_t n_blocks_count = 0;
3405         unsigned long old_sb_flags;
3406         struct ext4_mount_options old_opts;
3407         ext4_group_t g;
3408         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3409         int err;
3410 #ifdef CONFIG_QUOTA
3411         int i;
3412 #endif
3413
3414         /* Store the original options */
3415         old_sb_flags = sb->s_flags;
3416         old_opts.s_mount_opt = sbi->s_mount_opt;
3417         old_opts.s_resuid = sbi->s_resuid;
3418         old_opts.s_resgid = sbi->s_resgid;
3419         old_opts.s_commit_interval = sbi->s_commit_interval;
3420         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3421         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3422 #ifdef CONFIG_QUOTA
3423         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3424         for (i = 0; i < MAXQUOTAS; i++)
3425                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3426 #endif
3427         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3428                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3429
3430         /*
3431          * Allow the "check" option to be passed as a remount option.
3432          */
3433         if (!parse_options(data, sb, NULL, &journal_ioprio,
3434                            &n_blocks_count, 1)) {
3435                 err = -EINVAL;
3436                 goto restore_opts;
3437         }
3438
3439         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
3440                 ext4_abort(sb, __func__, "Abort forced by user");
3441
3442         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3443                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3444
3445         es = sbi->s_es;
3446
3447         if (sbi->s_journal) {
3448                 ext4_init_journal_params(sb, sbi->s_journal);
3449                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3450         }
3451
3452         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3453                 n_blocks_count > ext4_blocks_count(es)) {
3454                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3455                         err = -EROFS;
3456                         goto restore_opts;
3457                 }
3458
3459                 if (*flags & MS_RDONLY) {
3460                         /*
3461                          * First of all, the unconditional stuff we have to do
3462                          * to disable replay of the journal when we next remount
3463                          */
3464                         sb->s_flags |= MS_RDONLY;
3465
3466                         /*
3467                          * OK, test if we are remounting a valid rw partition
3468                          * readonly, and if so set the rdonly flag and then
3469                          * mark the partition as valid again.
3470                          */
3471                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3472                             (sbi->s_mount_state & EXT4_VALID_FS))
3473                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3474
3475                         if (sbi->s_journal)
3476                                 ext4_mark_recovery_complete(sb, es);
3477                 } else {
3478                         int ret;
3479                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3480                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3481                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3482                                        "remount RDWR because of unsupported "
3483                                        "optional features (%x).\n", sb->s_id,
3484                                 (le32_to_cpu(sbi->s_es->s_feature_ro_compat) &
3485                                         ~EXT4_FEATURE_RO_COMPAT_SUPP));
3486                                 err = -EROFS;
3487                                 goto restore_opts;
3488                         }
3489
3490                         /*
3491                          * Make sure the group descriptor checksums
3492                          * are sane.  If they aren't, refuse to remount r/w.
3493                          */
3494                         for (g = 0; g < sbi->s_groups_count; g++) {
3495                                 struct ext4_group_desc *gdp =
3496                                         ext4_get_group_desc(sb, g, NULL);
3497
3498                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3499                                         printk(KERN_ERR
3500                "EXT4-fs: ext4_remount: "
3501                 "Checksum for group %u failed (%u!=%u)\n",
3502                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3503                                                le16_to_cpu(gdp->bg_checksum));
3504                                         err = -EINVAL;
3505                                         goto restore_opts;
3506                                 }
3507                         }
3508
3509                         /*
3510                          * If we have an unprocessed orphan list hanging
3511                          * around from a previously readonly bdev mount,
3512                          * require a full umount/remount for now.
3513                          */
3514                         if (es->s_last_orphan) {
3515                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3516                                        "remount RDWR because of unprocessed "
3517                                        "orphan inode list.  Please "
3518                                        "umount/remount instead.\n",
3519                                        sb->s_id);
3520                                 err = -EINVAL;
3521                                 goto restore_opts;
3522                         }
3523
3524                         /*
3525                          * Mounting a RDONLY partition read-write, so reread
3526                          * and store the current valid flag.  (It may have
3527                          * been changed by e2fsck since we originally mounted
3528                          * the partition.)
3529                          */
3530                         if (sbi->s_journal)
3531                                 ext4_clear_journal_err(sb, es);
3532                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3533                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3534                                 goto restore_opts;
3535                         if (!ext4_setup_super(sb, es, 0))
3536                                 sb->s_flags &= ~MS_RDONLY;
3537                 }
3538         }
3539         ext4_setup_system_zone(sb);
3540         if (sbi->s_journal == NULL)
3541                 ext4_commit_super(sb, 1);
3542
3543 #ifdef CONFIG_QUOTA
3544         /* Release old quota file names */
3545         for (i = 0; i < MAXQUOTAS; i++)
3546                 if (old_opts.s_qf_names[i] &&
3547                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3548                         kfree(old_opts.s_qf_names[i]);
3549 #endif
3550         return 0;
3551
3552 restore_opts:
3553         sb->s_flags = old_sb_flags;
3554         sbi->s_mount_opt = old_opts.s_mount_opt;
3555         sbi->s_resuid = old_opts.s_resuid;
3556         sbi->s_resgid = old_opts.s_resgid;
3557         sbi->s_commit_interval = old_opts.s_commit_interval;
3558         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3559         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3560 #ifdef CONFIG_QUOTA
3561         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3562         for (i = 0; i < MAXQUOTAS; i++) {
3563                 if (sbi->s_qf_names[i] &&
3564                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3565                         kfree(sbi->s_qf_names[i]);
3566                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3567         }
3568 #endif
3569         return err;
3570 }
3571
3572 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3573 {
3574         struct super_block *sb = dentry->d_sb;
3575         struct ext4_sb_info *sbi = EXT4_SB(sb);
3576         struct ext4_super_block *es = sbi->s_es;
3577         u64 fsid;
3578
3579         if (test_opt(sb, MINIX_DF)) {
3580                 sbi->s_overhead_last = 0;
3581         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3582                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3583                 ext4_fsblk_t overhead = 0;
3584
3585                 /*
3586                  * Compute the overhead (FS structures).  This is constant
3587                  * for a given filesystem unless the number of block groups
3588                  * changes so we cache the previous value until it does.
3589                  */
3590
3591                 /*
3592                  * All of the blocks before first_data_block are
3593                  * overhead
3594                  */
3595                 overhead = le32_to_cpu(es->s_first_data_block);
3596
3597                 /*
3598                  * Add the overhead attributed to the superblock and
3599                  * block group descriptors.  If the sparse superblocks
3600                  * feature is turned on, then not all groups have this.
3601                  */
3602                 for (i = 0; i < ngroups; i++) {
3603                         overhead += ext4_bg_has_super(sb, i) +
3604                                 ext4_bg_num_gdb(sb, i);
3605                         cond_resched();
3606                 }
3607
3608                 /*
3609                  * Every block group has an inode bitmap, a block
3610                  * bitmap, and an inode table.
3611                  */
3612                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3613                 sbi->s_overhead_last = overhead;
3614                 smp_wmb();
3615                 sbi->s_blocks_last = ext4_blocks_count(es);
3616         }
3617
3618         buf->f_type = EXT4_SUPER_MAGIC;
3619         buf->f_bsize = sb->s_blocksize;
3620         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3621         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3622                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3623         ext4_free_blocks_count_set(es, buf->f_bfree);
3624         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3625         if (buf->f_bfree < ext4_r_blocks_count(es))
3626                 buf->f_bavail = 0;
3627         buf->f_files = le32_to_cpu(es->s_inodes_count);
3628         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3629         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3630         buf->f_namelen = EXT4_NAME_LEN;
3631         fsid = le64_to_cpup((void *)es->s_uuid) ^
3632                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3633         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3634         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3635
3636         return 0;
3637 }
3638
3639 /* Helper function for writing quotas on sync - we need to start transaction
3640  * before quota file is locked for write. Otherwise the are possible deadlocks:
3641  * Process 1                         Process 2
3642  * ext4_create()                     quota_sync()
3643  *   jbd2_journal_start()                  write_dquot()
3644  *   vfs_dq_init()                         down(dqio_mutex)
3645  *     down(dqio_mutex)                    jbd2_journal_start()
3646  *
3647  */
3648
3649 #ifdef CONFIG_QUOTA
3650
3651 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3652 {
3653         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3654 }
3655
3656 static int ext4_write_dquot(struct dquot *dquot)
3657 {
3658         int ret, err;
3659         handle_t *handle;
3660         struct inode *inode;
3661
3662         inode = dquot_to_inode(dquot);
3663         handle = ext4_journal_start(inode,
3664                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3665         if (IS_ERR(handle))
3666                 return PTR_ERR(handle);
3667         ret = dquot_commit(dquot);
3668         err = ext4_journal_stop(handle);
3669         if (!ret)
3670                 ret = err;
3671         return ret;
3672 }
3673
3674 static int ext4_acquire_dquot(struct dquot *dquot)
3675 {
3676         int ret, err;
3677         handle_t *handle;
3678
3679         handle = ext4_journal_start(dquot_to_inode(dquot),
3680                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3681         if (IS_ERR(handle))
3682                 return PTR_ERR(handle);
3683         ret = dquot_acquire(dquot);
3684         err = ext4_journal_stop(handle);
3685         if (!ret)
3686                 ret = err;
3687         return ret;
3688 }
3689
3690 static int ext4_release_dquot(struct dquot *dquot)
3691 {
3692         int ret, err;
3693         handle_t *handle;
3694
3695         handle = ext4_journal_start(dquot_to_inode(dquot),
3696                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3697         if (IS_ERR(handle)) {
3698                 /* Release dquot anyway to avoid endless cycle in dqput() */
3699                 dquot_release(dquot);
3700                 return PTR_ERR(handle);
3701         }
3702         ret = dquot_release(dquot);
3703         err = ext4_journal_stop(handle);
3704         if (!ret)
3705                 ret = err;
3706         return ret;
3707 }
3708
3709 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3710 {
3711         /* Are we journaling quotas? */
3712         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3713             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3714                 dquot_mark_dquot_dirty(dquot);
3715                 return ext4_write_dquot(dquot);
3716         } else {
3717                 return dquot_mark_dquot_dirty(dquot);
3718         }
3719 }
3720
3721 static int ext4_write_info(struct super_block *sb, int type)
3722 {
3723         int ret, err;
3724         handle_t *handle;
3725
3726         /* Data block + inode block */
3727         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3728         if (IS_ERR(handle))
3729                 return PTR_ERR(handle);
3730         ret = dquot_commit_info(sb, type);
3731         err = ext4_journal_stop(handle);
3732         if (!ret)
3733                 ret = err;
3734         return ret;
3735 }
3736
3737 /*
3738  * Turn on quotas during mount time - we need to find
3739  * the quota file and such...
3740  */
3741 static int ext4_quota_on_mount(struct super_block *sb, int type)
3742 {
3743         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3744                                   EXT4_SB(sb)->s_jquota_fmt, type);
3745 }
3746
3747 /*
3748  * Standard function to be called on quota_on
3749  */
3750 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3751                          char *name, int remount)
3752 {
3753         int err;
3754         struct path path;
3755
3756         if (!test_opt(sb, QUOTA))
3757                 return -EINVAL;
3758         /* When remounting, no checks are needed and in fact, name is NULL */
3759         if (remount)
3760                 return vfs_quota_on(sb, type, format_id, name, remount);
3761
3762         err = kern_path(name, LOOKUP_FOLLOW, &path);
3763         if (err)
3764                 return err;
3765
3766         /* Quotafile not on the same filesystem? */
3767         if (path.mnt->mnt_sb != sb) {
3768                 path_put(&path);
3769                 return -EXDEV;
3770         }
3771         /* Journaling quota? */
3772         if (EXT4_SB(sb)->s_qf_names[type]) {
3773                 /* Quotafile not in fs root? */
3774                 if (path.dentry->d_parent != sb->s_root)
3775                         printk(KERN_WARNING
3776                                 "EXT4-fs: Quota file not on filesystem root. "
3777                                 "Journaled quota will not work.\n");
3778         }
3779
3780         /*
3781          * When we journal data on quota file, we have to flush journal to see
3782          * all updates to the file when we bypass pagecache...
3783          */
3784         if (EXT4_SB(sb)->s_journal &&
3785             ext4_should_journal_data(path.dentry->d_inode)) {
3786                 /*
3787                  * We don't need to lock updates but journal_flush() could
3788                  * otherwise be livelocked...
3789                  */
3790                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3791                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3792                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3793                 if (err) {
3794                         path_put(&path);
3795                         return err;
3796                 }
3797         }
3798
3799         err = vfs_quota_on_path(sb, type, format_id, &path);
3800         path_put(&path);
3801         return err;
3802 }
3803
3804 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3805  * acquiring the locks... As quota files are never truncated and quota code
3806  * itself serializes the operations (and noone else should touch the files)
3807  * we don't have to be afraid of races */
3808 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3809                                size_t len, loff_t off)
3810 {
3811         struct inode *inode = sb_dqopt(sb)->files[type];
3812         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3813         int err = 0;
3814         int offset = off & (sb->s_blocksize - 1);
3815         int tocopy;
3816         size_t toread;
3817         struct buffer_head *bh;
3818         loff_t i_size = i_size_read(inode);
3819
3820         if (off > i_size)
3821                 return 0;
3822         if (off+len > i_size)
3823                 len = i_size-off;
3824         toread = len;
3825         while (toread > 0) {
3826                 tocopy = sb->s_blocksize - offset < toread ?
3827                                 sb->s_blocksize - offset : toread;
3828                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3829                 if (err)
3830                         return err;
3831                 if (!bh)        /* A hole? */
3832                         memset(data, 0, tocopy);
3833                 else
3834                         memcpy(data, bh->b_data+offset, tocopy);
3835                 brelse(bh);
3836                 offset = 0;
3837                 toread -= tocopy;
3838                 data += tocopy;
3839                 blk++;
3840         }
3841         return len;
3842 }
3843
3844 /* Write to quotafile (we know the transaction is already started and has
3845  * enough credits) */
3846 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3847                                 const char *data, size_t len, loff_t off)
3848 {
3849         struct inode *inode = sb_dqopt(sb)->files[type];
3850         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3851         int err = 0;
3852         int offset = off & (sb->s_blocksize - 1);
3853         int tocopy;
3854         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3855         size_t towrite = len;
3856         struct buffer_head *bh;
3857         handle_t *handle = journal_current_handle();
3858
3859         if (EXT4_SB(sb)->s_journal && !handle) {
3860                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%llu, len=%llu)"
3861                         " cancelled because transaction is not started.\n",
3862                         (unsigned long long)off, (unsigned long long)len);
3863                 return -EIO;
3864         }
3865         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3866         while (towrite > 0) {
3867                 tocopy = sb->s_blocksize - offset < towrite ?
3868                                 sb->s_blocksize - offset : towrite;
3869                 bh = ext4_bread(handle, inode, blk, 1, &err);
3870                 if (!bh)
3871                         goto out;
3872                 if (journal_quota) {
3873                         err = ext4_journal_get_write_access(handle, bh);
3874                         if (err) {
3875                                 brelse(bh);
3876                                 goto out;
3877                         }
3878                 }
3879                 lock_buffer(bh);
3880                 memcpy(bh->b_data+offset, data, tocopy);
3881                 flush_dcache_page(bh->b_page);
3882                 unlock_buffer(bh);
3883                 if (journal_quota)
3884                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3885                 else {
3886                         /* Always do at least ordered writes for quotas */
3887                         err = ext4_jbd2_file_inode(handle, inode);
3888                         mark_buffer_dirty(bh);
3889                 }
3890                 brelse(bh);
3891                 if (err)
3892                         goto out;
3893                 offset = 0;
3894                 towrite -= tocopy;
3895                 data += tocopy;
3896                 blk++;
3897         }
3898 out:
3899         if (len == towrite) {
3900                 mutex_unlock(&inode->i_mutex);
3901                 return err;
3902         }
3903         if (inode->i_size < off+len-towrite) {
3904                 i_size_write(inode, off+len-towrite);
3905                 EXT4_I(inode)->i_disksize = inode->i_size;
3906         }
3907         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3908         ext4_mark_inode_dirty(handle, inode);
3909         mutex_unlock(&inode->i_mutex);
3910         return len - towrite;
3911 }
3912
3913 #endif
3914
3915 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3916                        const char *dev_name, void *data, struct vfsmount *mnt)
3917 {
3918         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3919 }
3920
3921 static struct file_system_type ext4_fs_type = {
3922         .owner          = THIS_MODULE,
3923         .name           = "ext4",
3924         .get_sb         = ext4_get_sb,
3925         .kill_sb        = kill_block_super,
3926         .fs_flags       = FS_REQUIRES_DEV,
3927 };
3928
3929 #ifdef CONFIG_EXT4DEV_COMPAT
3930 static int ext4dev_get_sb(struct file_system_type *fs_type, int flags,
3931                           const char *dev_name, void *data,struct vfsmount *mnt)
3932 {
3933         printk(KERN_WARNING "EXT4-fs: Update your userspace programs "
3934                "to mount using ext4\n");
3935         printk(KERN_WARNING "EXT4-fs: ext4dev backwards compatibility "
3936                "will go away by 2.6.31\n");
3937         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3938 }
3939
3940 static struct file_system_type ext4dev_fs_type = {
3941         .owner          = THIS_MODULE,
3942         .name           = "ext4dev",
3943         .get_sb         = ext4dev_get_sb,
3944         .kill_sb        = kill_block_super,
3945         .fs_flags       = FS_REQUIRES_DEV,
3946 };
3947 MODULE_ALIAS("ext4dev");
3948 #endif
3949
3950 static int __init init_ext4_fs(void)
3951 {
3952         int err;
3953
3954         err = init_ext4_system_zone();
3955         if (err)
3956                 return err;
3957         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
3958         if (!ext4_kset)
3959                 goto out4;
3960         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
3961         err = init_ext4_mballoc();
3962         if (err)
3963                 goto out3;
3964
3965         err = init_ext4_xattr();
3966         if (err)
3967                 goto out2;
3968         err = init_inodecache();
3969         if (err)
3970                 goto out1;
3971         err = register_filesystem(&ext4_fs_type);
3972         if (err)
3973                 goto out;
3974 #ifdef CONFIG_EXT4DEV_COMPAT
3975         err = register_filesystem(&ext4dev_fs_type);
3976         if (err) {
3977                 unregister_filesystem(&ext4_fs_type);
3978                 goto out;
3979         }
3980 #endif
3981         return 0;
3982 out:
3983         destroy_inodecache();
3984 out1:
3985         exit_ext4_xattr();
3986 out2:
3987         exit_ext4_mballoc();
3988 out3:
3989         remove_proc_entry("fs/ext4", NULL);
3990         kset_unregister(ext4_kset);
3991 out4:
3992         exit_ext4_system_zone();
3993         return err;
3994 }
3995
3996 static void __exit exit_ext4_fs(void)
3997 {
3998         unregister_filesystem(&ext4_fs_type);
3999 #ifdef CONFIG_EXT4DEV_COMPAT
4000         unregister_filesystem(&ext4dev_fs_type);
4001 #endif
4002         destroy_inodecache();
4003         exit_ext4_xattr();
4004         exit_ext4_mballoc();
4005         remove_proc_entry("fs/ext4", NULL);
4006         kset_unregister(ext4_kset);
4007         exit_ext4_system_zone();
4008 }
4009
4010 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4011 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4012 MODULE_LICENSE("GPL");
4013 module_init(init_ext4_fs)
4014 module_exit(exit_ext4_fs)