fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/smp_lock.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/proc_fs.h>
  39 #include <linux/ctype.h>
  40 #include <linux/log2.h>
  41 #include <linux/crc16.h>
  42 #include <asm/uaccess.h>
  43
  44 #include "ext4.h"
  45 #include "ext4_jbd2.h"
  46 #include "xattr.h"
  47 #include "acl.h"
  48
  49 #define CREATE_TRACE_POINTS
  50 #include <trace/events/ext4.h>
  51
  52 static int default_mb_history_length = 1000;
  53
  54 module_param_named(default_mb_history_length, default_mb_history_length,
  55                    int, 0644);
  56 MODULE_PARM_DESC(default_mb_history_length,
  57                  "Default number of entries saved for mb_history");
  58
  59 struct proc_dir_entry *ext4_proc_root;
  60 static struct kset *ext4_kset;
  61
  62 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  63                              unsigned long journal_devnum);
  64 static int ext4_commit_super(struct super_block *sb, int sync);
  65 static void ext4_mark_recovery_complete(struct super_block *sb,
  66                                         struct ext4_super_block *es);
  67 static void ext4_clear_journal_err(struct super_block *sb,
  68                                    struct ext4_super_block *es);
  69 static int ext4_sync_fs(struct super_block *sb, int wait);
  70 static const char *ext4_decode_error(struct super_block *sb, int errno,
  71                                      char nbuf[16]);
  72 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  73 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  74 static int ext4_unfreeze(struct super_block *sb);
  75 static void ext4_write_super(struct super_block *sb);
  76 static int ext4_freeze(struct super_block *sb);
  77
  78
  79 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  80                                struct ext4_group_desc *bg)
  81 {
  82         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  83                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  84                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  85 }
  86
  87 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  88                                struct ext4_group_desc *bg)
  89 {
  90         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  91                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  92                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  93 }
  94
  95 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  96                               struct ext4_group_desc *bg)
  97 {
  98         return le32_to_cpu(bg->bg_inode_table_lo) |
  99                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 100                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 101 }
 102
 103 __u32 ext4_free_blks_count(struct super_block *sb,
 104                               struct ext4_group_desc *bg)
 105 {
 106         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 107                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 108                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 109 }
 110
 111 __u32 ext4_free_inodes_count(struct super_block *sb,
 112                               struct ext4_group_desc *bg)
 113 {
 114         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 115                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 116                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 117 }
 118
 119 __u32 ext4_used_dirs_count(struct super_block *sb,
 120                               struct ext4_group_desc *bg)
 121 {
 122         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 123                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 124                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 125 }
 126
 127 __u32 ext4_itable_unused_count(struct super_block *sb,
 128                               struct ext4_group_desc *bg)
 129 {
 130         return le16_to_cpu(bg->bg_itable_unused_lo) |
 131                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 132                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 133 }
 134
 135 void ext4_block_bitmap_set(struct super_block *sb,
 136                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 137 {
 138         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 139         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 140                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 141 }
 142
 143 void ext4_inode_bitmap_set(struct super_block *sb,
 144                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 145 {
 146         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 147         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 148                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 149 }
 150
 151 void ext4_inode_table_set(struct super_block *sb,
 152                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 153 {
 154         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 155         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 156                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 157 }
 158
 159 void ext4_free_blks_set(struct super_block *sb,
 160                           struct ext4_group_desc *bg, __u32 count)
 161 {
 162         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 163         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 164                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 165 }
 166
 167 void ext4_free_inodes_set(struct super_block *sb,
 168                           struct ext4_group_desc *bg, __u32 count)
 169 {
 170         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 171         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 172                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 173 }
 174
 175 void ext4_used_dirs_set(struct super_block *sb,
 176                           struct ext4_group_desc *bg, __u32 count)
 177 {
 178         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 179         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 180                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 181 }
 182
 183 void ext4_itable_unused_set(struct super_block *sb,
 184                           struct ext4_group_desc *bg, __u32 count)
 185 {
 186         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 187         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 188                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 189 }
 190
 191 /*
 192  * Wrappers for jbd2_journal_start/end.
 193  *
 194  * The only special thing we need to do here is to make sure that all
 195  * journal_end calls result in the superblock being marked dirty, so
 196  * that sync() will call the filesystem's write_super callback if
 197  * appropriate.
 198  */
 199 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 200 {
 201         journal_t *journal;
 202
 203         if (sb->s_flags & MS_RDONLY)
 204                 return ERR_PTR(-EROFS);
 205
 206         /* Special case here: if the journal has aborted behind our
 207          * backs (eg. EIO in the commit thread), then we still need to
 208          * take the FS itself readonly cleanly. */
 209         journal = EXT4_SB(sb)->s_journal;
 210         if (journal) {
 211                 if (is_journal_aborted(journal)) {
 212                         ext4_abort(sb, __func__, "Detected aborted journal");
 213                         return ERR_PTR(-EROFS);
 214                 }
 215                 return jbd2_journal_start(journal, nblocks);
 216         }
 217         /*
 218          * We're not journaling, return the appropriate indication.
 219          */
 220         current->journal_info = EXT4_NOJOURNAL_HANDLE;
 221         return current->journal_info;
 222 }
 223
 224 /*
 225  * The only special thing we need to do here is to make sure that all
 226  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 227  * that sync() will call the filesystem's write_super callback if
 228  * appropriate.
 229  */
 230 int __ext4_journal_stop(const char *where, handle_t *handle)
 231 {
 232         struct super_block *sb;
 233         int err;
 234         int rc;
 235
 236         if (!ext4_handle_valid(handle)) {
 237                 /*
 238                  * Do this here since we don't call jbd2_journal_stop() in
 239                  * no-journal mode.
 240                  */
 241                 current->journal_info = NULL;
 242                 return 0;
 243         }
 244         sb = handle->h_transaction->t_journal->j_private;
 245         err = handle->h_err;
 246         rc = jbd2_journal_stop(handle);
 247
 248         if (!err)
 249                 err = rc;
 250         if (err)
 251                 __ext4_std_error(sb, where, err);
 252         return err;
 253 }
 254
 255 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 256                 struct buffer_head *bh, handle_t *handle, int err)
 257 {
 258         char nbuf[16];
 259         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 260
 261         BUG_ON(!ext4_handle_valid(handle));
 262
 263         if (bh)
 264                 BUFFER_TRACE(bh, "abort");
 265
 266         if (!handle->h_err)
 267                 handle->h_err = err;
 268
 269         if (is_handle_aborted(handle))
 270                 return;
 271
 272         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 273                caller, errstr, err_fn);
 274
 275         jbd2_journal_abort_handle(handle);
 276 }
 277
 278 /* Deal with the reporting of failure conditions on a filesystem such as
 279  * inconsistencies detected or read IO failures.
 280  *
 281  * On ext2, we can store the error state of the filesystem in the
 282  * superblock.  That is not possible on ext4, because we may have other
 283  * write ordering constraints on the superblock which prevent us from
 284  * writing it out straight away; and given that the journal is about to
 285  * be aborted, we can't rely on the current, or future, transactions to
 286  * write out the superblock safely.
 287  *
 288  * We'll just use the jbd2_journal_abort() error code to record an error in
 289  * the journal instead.  On recovery, the journal will compain about
 290  * that error until we've noted it down and cleared it.
 291  */
 292
 293 static void ext4_handle_error(struct super_block *sb)
 294 {
 295         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 296
 297         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 298         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 299
 300         if (sb->s_flags & MS_RDONLY)
 301                 return;
 302
 303         if (!test_opt(sb, ERRORS_CONT)) {
 304                 journal_t *journal = EXT4_SB(sb)->s_journal;
 305
 306                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 307                 if (journal)
 308                         jbd2_journal_abort(journal, -EIO);
 309         }
 310         if (test_opt(sb, ERRORS_RO)) {
 311                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 312                 sb->s_flags |= MS_RDONLY;
 313         }
 314         ext4_commit_super(sb, 1);
 315         if (test_opt(sb, ERRORS_PANIC))
 316                 panic("EXT4-fs (device %s): panic forced after error\n",
 317                         sb->s_id);
 318 }
 319
 320 void ext4_error(struct super_block *sb, const char *function,
 321                 const char *fmt, ...)
 322 {
 323         va_list args;
 324
 325         va_start(args, fmt);
 326         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 327         vprintk(fmt, args);
 328         printk("\n");
 329         va_end(args);
 330
 331         ext4_handle_error(sb);
 332 }
 333
 334 static const char *ext4_decode_error(struct super_block *sb, int errno,
 335                                      char nbuf[16])
 336 {
 337         char *errstr = NULL;
 338
 339         switch (errno) {
 340         case -EIO:
 341                 errstr = "IO failure";
 342                 break;
 343         case -ENOMEM:
 344                 errstr = "Out of memory";
 345                 break;
 346         case -EROFS:
 347                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 348                         errstr = "Journal has aborted";
 349                 else
 350                         errstr = "Readonly filesystem";
 351                 break;
 352         default:
 353                 /* If the caller passed in an extra buffer for unknown
 354                  * errors, textualise them now.  Else we just return
 355                  * NULL. */
 356                 if (nbuf) {
 357                         /* Check for truncated error codes... */
 358                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 359                                 errstr = nbuf;
 360                 }
 361                 break;
 362         }
 363
 364         return errstr;
 365 }
 366
 367 /* __ext4_std_error decodes expected errors from journaling functions
 368  * automatically and invokes the appropriate error response.  */
 369
 370 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 371 {
 372         char nbuf[16];
 373         const char *errstr;
 374
 375         /* Special case: if the error is EROFS, and we're not already
 376          * inside a transaction, then there's really no point in logging
 377          * an error. */
 378         if (errno == -EROFS && journal_current_handle() == NULL &&
 379             (sb->s_flags & MS_RDONLY))
 380                 return;
 381
 382         errstr = ext4_decode_error(sb, errno, nbuf);
 383         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 384                sb->s_id, function, errstr);
 385
 386         ext4_handle_error(sb);
 387 }
 388
 389 /*
 390  * ext4_abort is a much stronger failure handler than ext4_error.  The
 391  * abort function may be used to deal with unrecoverable failures such
 392  * as journal IO errors or ENOMEM at a critical moment in log management.
 393  *
 394  * We unconditionally force the filesystem into an ABORT|READONLY state,
 395  * unless the error response on the fs has been set to panic in which
 396  * case we take the easy way out and panic immediately.
 397  */
 398
 399 void ext4_abort(struct super_block *sb, const char *function,
 400                 const char *fmt, ...)
 401 {
 402         va_list args;
 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         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 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_msg (struct super_block * sb, const char *prefix,
 425                    const char *fmt, ...)
 426 {
 427         va_list args;
 428
 429         va_start(args, fmt);
 430         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
 431         vprintk(fmt, args);
 432         printk("\n");
 433         va_end(args);
 434 }
 435
 436 void ext4_warning(struct super_block *sb, const char *function,
 437                   const char *fmt, ...)
 438 {
 439         va_list args;
 440
 441         va_start(args, fmt);
 442         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 443                sb->s_id, function);
 444         vprintk(fmt, args);
 445         printk("\n");
 446         va_end(args);
 447 }
 448
 449 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
 450                            const char *function, const char *fmt, ...)
 451 __releases(bitlock)
 452 __acquires(bitlock)
 453 {
 454         va_list args;
 455         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 456
 457         va_start(args, fmt);
 458         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 459         vprintk(fmt, args);
 460         printk("\n");
 461         va_end(args);
 462
 463         if (test_opt(sb, ERRORS_CONT)) {
 464                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 465                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 466                 ext4_commit_super(sb, 0);
 467                 return;
 468         }
 469         ext4_unlock_group(sb, grp);
 470         ext4_handle_error(sb);
 471         /*
 472          * We only get here in the ERRORS_RO case; relocking the group
 473          * may be dangerous, but nothing bad will happen since the
 474          * filesystem will have already been marked read/only and the
 475          * journal has been aborted.  We return 1 as a hint to callers
 476          * who might what to use the return value from
 477          * ext4_grp_locked_error() to distinguish beween the
 478          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 479          * aggressively from the ext4 function in question, with a
 480          * more appropriate error code.
 481          */
 482         ext4_lock_group(sb, grp);
 483         return;
 484 }
 485
 486 void ext4_update_dynamic_rev(struct super_block *sb)
 487 {
 488         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 489
 490         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 491                 return;
 492
 493         ext4_warning(sb, __func__,
 494                      "updating to rev %d because of new feature flag, "
 495                      "running e2fsck is recommended",
 496                      EXT4_DYNAMIC_REV);
 497
 498         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 499         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 500         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 501         /* leave es->s_feature_*compat flags alone */
 502         /* es->s_uuid will be set by e2fsck if empty */
 503
 504         /*
 505          * The rest of the superblock fields should be zero, and if not it
 506          * means they are likely already in use, so leave them alone.  We
 507          * can leave it up to e2fsck to clean up any inconsistencies there.
 508          */
 509 }
 510
 511 /*
 512  * Open the external journal device
 513  */
 514 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 515 {
 516         struct block_device *bdev;
 517         char b[BDEVNAME_SIZE];
 518
 519         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 520         if (IS_ERR(bdev))
 521                 goto fail;
 522         return bdev;
 523
 524 fail:
 525         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 526                         __bdevname(dev, b), PTR_ERR(bdev));
 527         return NULL;
 528 }
 529
 530 /*
 531  * Release the journal device
 532  */
 533 static int ext4_blkdev_put(struct block_device *bdev)
 534 {
 535         bd_release(bdev);
 536         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 537 }
 538
 539 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 540 {
 541         struct block_device *bdev;
 542         int ret = -ENODEV;
 543
 544         bdev = sbi->journal_bdev;
 545         if (bdev) {
 546                 ret = ext4_blkdev_put(bdev);
 547                 sbi->journal_bdev = NULL;
 548         }
 549         return ret;
 550 }
 551
 552 static inline struct inode *orphan_list_entry(struct list_head *l)
 553 {
 554         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 555 }
 556
 557 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 558 {
 559         struct list_head *l;
 560
 561         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 562                  le32_to_cpu(sbi->s_es->s_last_orphan));
 563
 564         printk(KERN_ERR "sb_info orphan list:\n");
 565         list_for_each(l, &sbi->s_orphan) {
 566                 struct inode *inode = orphan_list_entry(l);
 567                 printk(KERN_ERR "  "
 568                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 569                        inode->i_sb->s_id, inode->i_ino, inode,
 570                        inode->i_mode, inode->i_nlink,
 571                        NEXT_ORPHAN(inode));
 572         }
 573 }
 574
 575 static void ext4_put_super(struct super_block *sb)
 576 {
 577         struct ext4_sb_info *sbi = EXT4_SB(sb);
 578         struct ext4_super_block *es = sbi->s_es;
 579         int i, err;
 580
 581         lock_super(sb);
 582         lock_kernel();
 583         if (sb->s_dirt)
 584                 ext4_commit_super(sb, 1);
 585
 586         ext4_release_system_zone(sb);
 587         ext4_mb_release(sb);
 588         ext4_ext_release(sb);
 589         ext4_xattr_put_super(sb);
 590         if (sbi->s_journal) {
 591                 err = jbd2_journal_destroy(sbi->s_journal);
 592                 sbi->s_journal = NULL;
 593                 if (err < 0)
 594                         ext4_abort(sb, __func__,
 595                                    "Couldn't clean up the journal");
 596         }
 597         if (!(sb->s_flags & MS_RDONLY)) {
 598                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 599                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 600                 ext4_commit_super(sb, 1);
 601         }
 602         if (sbi->s_proc) {
 603                 remove_proc_entry(sb->s_id, ext4_proc_root);
 604         }
 605         kobject_del(&sbi->s_kobj);
 606
 607         for (i = 0; i < sbi->s_gdb_count; i++)
 608                 brelse(sbi->s_group_desc[i]);
 609         kfree(sbi->s_group_desc);
 610         if (is_vmalloc_addr(sbi->s_flex_groups))
 611                 vfree(sbi->s_flex_groups);
 612         else
 613                 kfree(sbi->s_flex_groups);
 614         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 615         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 616         percpu_counter_destroy(&sbi->s_dirs_counter);
 617         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 618         brelse(sbi->s_sbh);
 619 #ifdef CONFIG_QUOTA
 620         for (i = 0; i < MAXQUOTAS; i++)
 621                 kfree(sbi->s_qf_names[i]);
 622 #endif
 623
 624         /* Debugging code just in case the in-memory inode orphan list
 625          * isn't empty.  The on-disk one can be non-empty if we've
 626          * detected an error and taken the fs readonly, but the
 627          * in-memory list had better be clean by this point. */
 628         if (!list_empty(&sbi->s_orphan))
 629                 dump_orphan_list(sb, sbi);
 630         J_ASSERT(list_empty(&sbi->s_orphan));
 631
 632         invalidate_bdev(sb->s_bdev);
 633         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 634                 /*
 635                  * Invalidate the journal device's buffers.  We don't want them
 636                  * floating about in memory - the physical journal device may
 637                  * hotswapped, and it breaks the `ro-after' testing code.
 638                  */
 639                 sync_blockdev(sbi->journal_bdev);
 640                 invalidate_bdev(sbi->journal_bdev);
 641                 ext4_blkdev_remove(sbi);
 642         }
 643         sb->s_fs_info = NULL;
 644         /*
 645          * Now that we are completely done shutting down the
 646          * superblock, we need to actually destroy the kobject.
 647          */
 648         unlock_kernel();
 649         unlock_super(sb);
 650         kobject_put(&sbi->s_kobj);
 651         wait_for_completion(&sbi->s_kobj_unregister);
 652         kfree(sbi->s_blockgroup_lock);
 653         kfree(sbi);
 654 }
 655
 656 static struct kmem_cache *ext4_inode_cachep;
 657
 658 /*
 659  * Called inside transaction, so use GFP_NOFS
 660  */
 661 static struct inode *ext4_alloc_inode(struct super_block *sb)
 662 {
 663         struct ext4_inode_info *ei;
 664
 665         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 666         if (!ei)
 667                 return NULL;
 668
 669 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 670         ei->i_acl = EXT4_ACL_NOT_CACHED;
 671         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 672 #endif
 673         ei->vfs_inode.i_version = 1;
 674         ei->vfs_inode.i_data.writeback_index = 0;
 675         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 676         INIT_LIST_HEAD(&ei->i_prealloc_list);
 677         spin_lock_init(&ei->i_prealloc_lock);
 678         /*
 679          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 680          * therefore it can be null here.  Don't check it, just initialize
 681          * jinode.
 682          */
 683         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 684         ei->i_reserved_data_blocks = 0;
 685         ei->i_reserved_meta_blocks = 0;
 686         ei->i_allocated_meta_blocks = 0;
 687         ei->i_delalloc_reserved_flag = 0;
 688         spin_lock_init(&(ei->i_block_reservation_lock));
 689
 690         return &ei->vfs_inode;
 691 }
 692
 693 static void ext4_destroy_inode(struct inode *inode)
 694 {
 695         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 696                 ext4_msg(inode->i_sb, KERN_ERR,
 697                          "Inode %lu (%p): orphan list check failed!",
 698                          inode->i_ino, EXT4_I(inode));
 699                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 700                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 701                                 true);
 702                 dump_stack();
 703         }
 704         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 705 }
 706
 707 static void init_once(void *foo)
 708 {
 709         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 710
 711         INIT_LIST_HEAD(&ei->i_orphan);
 712 #ifdef CONFIG_EXT4_FS_XATTR
 713         init_rwsem(&ei->xattr_sem);
 714 #endif
 715         init_rwsem(&ei->i_data_sem);
 716         inode_init_once(&ei->vfs_inode);
 717 }
 718
 719 static int init_inodecache(void)
 720 {
 721         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 722                                              sizeof(struct ext4_inode_info),
 723                                              0, (SLAB_RECLAIM_ACCOUNT|
 724                                                 SLAB_MEM_SPREAD),
 725                                              init_once);
 726         if (ext4_inode_cachep == NULL)
 727                 return -ENOMEM;
 728         return 0;
 729 }
 730
 731 static void destroy_inodecache(void)
 732 {
 733         kmem_cache_destroy(ext4_inode_cachep);
 734 }
 735
 736 static void ext4_clear_inode(struct inode *inode)
 737 {
 738 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 739         if (EXT4_I(inode)->i_acl &&
 740                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 741                 posix_acl_release(EXT4_I(inode)->i_acl);
 742                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 743         }
 744         if (EXT4_I(inode)->i_default_acl &&
 745                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 746                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 747                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 748         }
 749 #endif
 750         ext4_discard_preallocations(inode);
 751         if (EXT4_JOURNAL(inode))
 752                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 753                                        &EXT4_I(inode)->jinode);
 754 }
 755
 756 static inline void ext4_show_quota_options(struct seq_file *seq,
 757                                            struct super_block *sb)
 758 {
 759 #if defined(CONFIG_QUOTA)
 760         struct ext4_sb_info *sbi = EXT4_SB(sb);
 761
 762         if (sbi->s_jquota_fmt)
 763                 seq_printf(seq, ",jqfmt=%s",
 764                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 765
 766         if (sbi->s_qf_names[USRQUOTA])
 767                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 768
 769         if (sbi->s_qf_names[GRPQUOTA])
 770                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 771
 772         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 773                 seq_puts(seq, ",usrquota");
 774
 775         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 776                 seq_puts(seq, ",grpquota");
 777 #endif
 778 }
 779
 780 /*
 781  * Show an option if
 782  *  - it's set to a non-default value OR
 783  *  - if the per-sb default is different from the global default
 784  */
 785 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 786 {
 787         int def_errors;
 788         unsigned long def_mount_opts;
 789         struct super_block *sb = vfs->mnt_sb;
 790         struct ext4_sb_info *sbi = EXT4_SB(sb);
 791         struct ext4_super_block *es = sbi->s_es;
 792
 793         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 794         def_errors     = le16_to_cpu(es->s_errors);
 795
 796         if (sbi->s_sb_block != 1)
 797                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 798         if (test_opt(sb, MINIX_DF))
 799                 seq_puts(seq, ",minixdf");
 800         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 801                 seq_puts(seq, ",grpid");
 802         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 803                 seq_puts(seq, ",nogrpid");
 804         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 805             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 806                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 807         }
 808         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 809             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 810                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 811         }
 812         if (test_opt(sb, ERRORS_RO)) {
 813                 if (def_errors == EXT4_ERRORS_PANIC ||
 814                     def_errors == EXT4_ERRORS_CONTINUE) {
 815                         seq_puts(seq, ",errors=remount-ro");
 816                 }
 817         }
 818         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 819                 seq_puts(seq, ",errors=continue");
 820         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 821                 seq_puts(seq, ",errors=panic");
 822         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 823                 seq_puts(seq, ",nouid32");
 824         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 825                 seq_puts(seq, ",debug");
 826         if (test_opt(sb, OLDALLOC))
 827                 seq_puts(seq, ",oldalloc");
 828 #ifdef CONFIG_EXT4_FS_XATTR
 829         if (test_opt(sb, XATTR_USER) &&
 830                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 831                 seq_puts(seq, ",user_xattr");
 832         if (!test_opt(sb, XATTR_USER) &&
 833             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 834                 seq_puts(seq, ",nouser_xattr");
 835         }
 836 #endif
 837 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 838         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 839                 seq_puts(seq, ",acl");
 840         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 841                 seq_puts(seq, ",noacl");
 842 #endif
 843         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 844                 seq_printf(seq, ",commit=%u",
 845                            (unsigned) (sbi->s_commit_interval / HZ));
 846         }
 847         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 848                 seq_printf(seq, ",min_batch_time=%u",
 849                            (unsigned) sbi->s_min_batch_time);
 850         }
 851         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 852                 seq_printf(seq, ",max_batch_time=%u",
 853                            (unsigned) sbi->s_min_batch_time);
 854         }
 855
 856         /*
 857          * We're changing the default of barrier mount option, so
 858          * let's always display its mount state so it's clear what its
 859          * status is.
 860          */
 861         seq_puts(seq, ",barrier=");
 862         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 863         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 864                 seq_puts(seq, ",journal_async_commit");
 865         if (test_opt(sb, NOBH))
 866                 seq_puts(seq, ",nobh");
 867         if (test_opt(sb, I_VERSION))
 868                 seq_puts(seq, ",i_version");
 869         if (!test_opt(sb, DELALLOC))
 870                 seq_puts(seq, ",nodelalloc");
 871
 872
 873         if (sbi->s_stripe)
 874                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 875         /*
 876          * journal mode get enabled in different ways
 877          * So just print the value even if we didn't specify it
 878          */
 879         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 880                 seq_puts(seq, ",data=journal");
 881         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 882                 seq_puts(seq, ",data=ordered");
 883         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 884                 seq_puts(seq, ",data=writeback");
 885
 886         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 887                 seq_printf(seq, ",inode_readahead_blks=%u",
 888                            sbi->s_inode_readahead_blks);
 889
 890         if (test_opt(sb, DATA_ERR_ABORT))
 891                 seq_puts(seq, ",data_err=abort");
 892
 893         if (test_opt(sb, NO_AUTO_DA_ALLOC))
 894                 seq_puts(seq, ",noauto_da_alloc");
 895
 896         ext4_show_quota_options(seq, sb);
 897
 898         return 0;
 899 }
 900
 901 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 902                                         u64 ino, u32 generation)
 903 {
 904         struct inode *inode;
 905
 906         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 907                 return ERR_PTR(-ESTALE);
 908         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 909                 return ERR_PTR(-ESTALE);
 910
 911         /* iget isn't really right if the inode is currently unallocated!!
 912          *
 913          * ext4_read_inode will return a bad_inode if the inode had been
 914          * deleted, so we should be safe.
 915          *
 916          * Currently we don't know the generation for parent directory, so
 917          * a generation of 0 means "accept any"
 918          */
 919         inode = ext4_iget(sb, ino);
 920         if (IS_ERR(inode))
 921                 return ERR_CAST(inode);
 922         if (generation && inode->i_generation != generation) {
 923                 iput(inode);
 924                 return ERR_PTR(-ESTALE);
 925         }
 926
 927         return inode;
 928 }
 929
 930 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 931                                         int fh_len, int fh_type)
 932 {
 933         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 934                                     ext4_nfs_get_inode);
 935 }
 936
 937 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 938                                         int fh_len, int fh_type)
 939 {
 940         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 941                                     ext4_nfs_get_inode);
 942 }
 943
 944 /*
 945  * Try to release metadata pages (indirect blocks, directories) which are
 946  * mapped via the block device.  Since these pages could have journal heads
 947  * which would prevent try_to_free_buffers() from freeing them, we must use
 948  * jbd2 layer's try_to_free_buffers() function to release them.
 949  */
 950 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 951                                  gfp_t wait)
 952 {
 953         journal_t *journal = EXT4_SB(sb)->s_journal;
 954
 955         WARN_ON(PageChecked(page));
 956         if (!page_has_buffers(page))
 957                 return 0;
 958         if (journal)
 959                 return jbd2_journal_try_to_free_buffers(journal, page,
 960                                                         wait & ~__GFP_WAIT);
 961         return try_to_free_buffers(page);
 962 }
 963
 964 #ifdef CONFIG_QUOTA
 965 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 966 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 967
 968 static int ext4_write_dquot(struct dquot *dquot);
 969 static int ext4_acquire_dquot(struct dquot *dquot);
 970 static int ext4_release_dquot(struct dquot *dquot);
 971 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 972 static int ext4_write_info(struct super_block *sb, int type);
 973 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 974                                 char *path, int remount);
 975 static int ext4_quota_on_mount(struct super_block *sb, int type);
 976 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 977                                size_t len, loff_t off);
 978 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 979                                 const char *data, size_t len, loff_t off);
 980
 981 static struct dquot_operations ext4_quota_operations = {
 982         .initialize     = dquot_initialize,
 983         .drop           = dquot_drop,
 984         .alloc_space    = dquot_alloc_space,
 985         .reserve_space  = dquot_reserve_space,
 986         .claim_space    = dquot_claim_space,
 987         .release_rsv    = dquot_release_reserved_space,
 988         .get_reserved_space = ext4_get_reserved_space,
 989         .alloc_inode    = dquot_alloc_inode,
 990         .free_space     = dquot_free_space,
 991         .free_inode     = dquot_free_inode,
 992         .transfer       = dquot_transfer,
 993         .write_dquot    = ext4_write_dquot,
 994         .acquire_dquot  = ext4_acquire_dquot,
 995         .release_dquot  = ext4_release_dquot,
 996         .mark_dirty     = ext4_mark_dquot_dirty,
 997         .write_info     = ext4_write_info,
 998         .alloc_dquot    = dquot_alloc,
 999         .destroy_dquot  = dquot_destroy,
1000 };
1001
1002 static struct quotactl_ops ext4_qctl_operations = {
1003         .quota_on       = ext4_quota_on,
1004         .quota_off      = vfs_quota_off,
1005         .quota_sync     = vfs_quota_sync,
1006         .get_info       = vfs_get_dqinfo,
1007         .set_info       = vfs_set_dqinfo,
1008         .get_dqblk      = vfs_get_dqblk,
1009         .set_dqblk      = vfs_set_dqblk
1010 };
1011 #endif
1012
1013 static const struct super_operations ext4_sops = {
1014         .alloc_inode    = ext4_alloc_inode,
1015         .destroy_inode  = ext4_destroy_inode,
1016         .write_inode    = ext4_write_inode,
1017         .dirty_inode    = ext4_dirty_inode,
1018         .delete_inode   = ext4_delete_inode,
1019         .put_super      = ext4_put_super,
1020         .sync_fs        = ext4_sync_fs,
1021         .freeze_fs      = ext4_freeze,
1022         .unfreeze_fs    = ext4_unfreeze,
1023         .statfs         = ext4_statfs,
1024         .remount_fs     = ext4_remount,
1025         .clear_inode    = ext4_clear_inode,
1026         .show_options   = ext4_show_options,
1027 #ifdef CONFIG_QUOTA
1028         .quota_read     = ext4_quota_read,
1029         .quota_write    = ext4_quota_write,
1030 #endif
1031         .bdev_try_to_free_page = bdev_try_to_free_page,
1032 };
1033
1034 static const struct super_operations ext4_nojournal_sops = {
1035         .alloc_inode    = ext4_alloc_inode,
1036         .destroy_inode  = ext4_destroy_inode,
1037         .write_inode    = ext4_write_inode,
1038         .dirty_inode    = ext4_dirty_inode,
1039         .delete_inode   = ext4_delete_inode,
1040         .write_super    = ext4_write_super,
1041         .put_super      = ext4_put_super,
1042         .statfs         = ext4_statfs,
1043         .remount_fs     = ext4_remount,
1044         .clear_inode    = ext4_clear_inode,
1045         .show_options   = ext4_show_options,
1046 #ifdef CONFIG_QUOTA
1047         .quota_read     = ext4_quota_read,
1048         .quota_write    = ext4_quota_write,
1049 #endif
1050         .bdev_try_to_free_page = bdev_try_to_free_page,
1051 };
1052
1053 static const struct export_operations ext4_export_ops = {
1054         .fh_to_dentry = ext4_fh_to_dentry,
1055         .fh_to_parent = ext4_fh_to_parent,
1056         .get_parent = ext4_get_parent,
1057 };
1058
1059 enum {
1060         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1061         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1062         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1063         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1064         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1065         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1066         Opt_journal_update, Opt_journal_dev,
1067         Opt_journal_checksum, Opt_journal_async_commit,
1068         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1069         Opt_data_err_abort, Opt_data_err_ignore, Opt_mb_history_length,
1070         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1071         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
1072         Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err, Opt_resize,
1073         Opt_usrquota, Opt_grpquota, Opt_i_version,
1074         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1075         Opt_block_validity, Opt_noblock_validity,
1076         Opt_inode_readahead_blks, Opt_journal_ioprio
1077 };
1078
1079 static const match_table_t tokens = {
1080         {Opt_bsd_df, "bsddf"},
1081         {Opt_minix_df, "minixdf"},
1082         {Opt_grpid, "grpid"},
1083         {Opt_grpid, "bsdgroups"},
1084         {Opt_nogrpid, "nogrpid"},
1085         {Opt_nogrpid, "sysvgroups"},
1086         {Opt_resgid, "resgid=%u"},
1087         {Opt_resuid, "resuid=%u"},
1088         {Opt_sb, "sb=%u"},
1089         {Opt_err_cont, "errors=continue"},
1090         {Opt_err_panic, "errors=panic"},
1091         {Opt_err_ro, "errors=remount-ro"},
1092         {Opt_nouid32, "nouid32"},
1093         {Opt_debug, "debug"},
1094         {Opt_oldalloc, "oldalloc"},
1095         {Opt_orlov, "orlov"},
1096         {Opt_user_xattr, "user_xattr"},
1097         {Opt_nouser_xattr, "nouser_xattr"},
1098         {Opt_acl, "acl"},
1099         {Opt_noacl, "noacl"},
1100         {Opt_noload, "noload"},
1101         {Opt_nobh, "nobh"},
1102         {Opt_bh, "bh"},
1103         {Opt_commit, "commit=%u"},
1104         {Opt_min_batch_time, "min_batch_time=%u"},
1105         {Opt_max_batch_time, "max_batch_time=%u"},
1106         {Opt_journal_update, "journal=update"},
1107         {Opt_journal_dev, "journal_dev=%u"},
1108         {Opt_journal_checksum, "journal_checksum"},
1109         {Opt_journal_async_commit, "journal_async_commit"},
1110         {Opt_abort, "abort"},
1111         {Opt_data_journal, "data=journal"},
1112         {Opt_data_ordered, "data=ordered"},
1113         {Opt_data_writeback, "data=writeback"},
1114         {Opt_data_err_abort, "data_err=abort"},
1115         {Opt_data_err_ignore, "data_err=ignore"},
1116         {Opt_mb_history_length, "mb_history_length=%u"},
1117         {Opt_offusrjquota, "usrjquota="},
1118         {Opt_usrjquota, "usrjquota=%s"},
1119         {Opt_offgrpjquota, "grpjquota="},
1120         {Opt_grpjquota, "grpjquota=%s"},
1121         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1122         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1123         {Opt_grpquota, "grpquota"},
1124         {Opt_noquota, "noquota"},
1125         {Opt_quota, "quota"},
1126         {Opt_usrquota, "usrquota"},
1127         {Opt_barrier, "barrier=%u"},
1128         {Opt_barrier, "barrier"},
1129         {Opt_nobarrier, "nobarrier"},
1130         {Opt_i_version, "i_version"},
1131         {Opt_stripe, "stripe=%u"},
1132         {Opt_resize, "resize"},
1133         {Opt_delalloc, "delalloc"},
1134         {Opt_nodelalloc, "nodelalloc"},
1135         {Opt_block_validity, "block_validity"},
1136         {Opt_noblock_validity, "noblock_validity"},
1137         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1138         {Opt_journal_ioprio, "journal_ioprio=%u"},
1139         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1140         {Opt_auto_da_alloc, "auto_da_alloc"},
1141         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1142         {Opt_err, NULL},
1143 };
1144
1145 static ext4_fsblk_t get_sb_block(void **data)
1146 {
1147         ext4_fsblk_t    sb_block;
1148         char            *options = (char *) *data;
1149
1150         if (!options || strncmp(options, "sb=", 3) != 0)
1151                 return 1;       /* Default location */
1152
1153         options += 3;
1154         /* TODO: use simple_strtoll with >32bit ext4 */
1155         sb_block = simple_strtoul(options, &options, 0);
1156         if (*options && *options != ',') {
1157                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1158                        (char *) *data);
1159                 return 1;
1160         }
1161         if (*options == ',')
1162                 options++;
1163         *data = (void *) options;
1164
1165         return sb_block;
1166 }
1167
1168 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1169
1170 static int parse_options(char *options, struct super_block *sb,
1171                          unsigned long *journal_devnum,
1172                          unsigned int *journal_ioprio,
1173                          ext4_fsblk_t *n_blocks_count, int is_remount)
1174 {
1175         struct ext4_sb_info *sbi = EXT4_SB(sb);
1176         char *p;
1177         substring_t args[MAX_OPT_ARGS];
1178         int data_opt = 0;
1179         int option;
1180 #ifdef CONFIG_QUOTA
1181         int qtype, qfmt;
1182         char *qname;
1183 #endif
1184
1185         if (!options)
1186                 return 1;
1187
1188         while ((p = strsep(&options, ",")) != NULL) {
1189                 int token;
1190                 if (!*p)
1191                         continue;
1192
1193                 token = match_token(p, tokens, args);
1194                 switch (token) {
1195                 case Opt_bsd_df:
1196                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1197                         break;
1198                 case Opt_minix_df:
1199                         set_opt(sbi->s_mount_opt, MINIX_DF);
1200                         break;
1201                 case Opt_grpid:
1202                         set_opt(sbi->s_mount_opt, GRPID);
1203                         break;
1204                 case Opt_nogrpid:
1205                         clear_opt(sbi->s_mount_opt, GRPID);
1206                         break;
1207                 case Opt_resuid:
1208                         if (match_int(&args[0], &option))
1209                                 return 0;
1210                         sbi->s_resuid = option;
1211                         break;
1212                 case Opt_resgid:
1213                         if (match_int(&args[0], &option))
1214                                 return 0;
1215                         sbi->s_resgid = option;
1216                         break;
1217                 case Opt_sb:
1218                         /* handled by get_sb_block() instead of here */
1219                         /* *sb_block = match_int(&args[0]); */
1220                         break;
1221                 case Opt_err_panic:
1222                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1223                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1224                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1225                         break;
1226                 case Opt_err_ro:
1227                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1228                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1229                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1230                         break;
1231                 case Opt_err_cont:
1232                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1233                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1234                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1235                         break;
1236                 case Opt_nouid32:
1237                         set_opt(sbi->s_mount_opt, NO_UID32);
1238                         break;
1239                 case Opt_debug:
1240                         set_opt(sbi->s_mount_opt, DEBUG);
1241                         break;
1242                 case Opt_oldalloc:
1243                         set_opt(sbi->s_mount_opt, OLDALLOC);
1244                         break;
1245                 case Opt_orlov:
1246                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1247                         break;
1248 #ifdef CONFIG_EXT4_FS_XATTR
1249                 case Opt_user_xattr:
1250                         set_opt(sbi->s_mount_opt, XATTR_USER);
1251                         break;
1252                 case Opt_nouser_xattr:
1253                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1254                         break;
1255 #else
1256                 case Opt_user_xattr:
1257                 case Opt_nouser_xattr:
1258                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1259                         break;
1260 #endif
1261 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1262                 case Opt_acl:
1263                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1264                         break;
1265                 case Opt_noacl:
1266                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1267                         break;
1268 #else
1269                 case Opt_acl:
1270                 case Opt_noacl:
1271                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1272                         break;
1273 #endif
1274                 case Opt_journal_update:
1275                         /* @@@ FIXME */
1276                         /* Eventually we will want to be able to create
1277                            a journal file here.  For now, only allow the
1278                            user to specify an existing inode to be the
1279                            journal file. */
1280                         if (is_remount) {
1281                                 ext4_msg(sb, KERN_ERR,
1282                                          "Cannot specify journal on remount");
1283                                 return 0;
1284                         }
1285                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1286                         break;
1287                 case Opt_journal_dev:
1288                         if (is_remount) {
1289                                 ext4_msg(sb, KERN_ERR,
1290                                         "Cannot specify journal on remount");
1291                                 return 0;
1292                         }
1293                         if (match_int(&args[0], &option))
1294                                 return 0;
1295                         *journal_devnum = option;
1296                         break;
1297                 case Opt_journal_checksum:
1298                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1299                         break;
1300                 case Opt_journal_async_commit:
1301                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1302                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1303                         break;
1304                 case Opt_noload:
1305                         set_opt(sbi->s_mount_opt, NOLOAD);
1306                         break;
1307                 case Opt_commit:
1308                         if (match_int(&args[0], &option))
1309                                 return 0;
1310                         if (option < 0)
1311                                 return 0;
1312                         if (option == 0)
1313                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1314                         sbi->s_commit_interval = HZ * option;
1315                         break;
1316                 case Opt_max_batch_time:
1317                         if (match_int(&args[0], &option))
1318                                 return 0;
1319                         if (option < 0)
1320                                 return 0;
1321                         if (option == 0)
1322                                 option = EXT4_DEF_MAX_BATCH_TIME;
1323                         sbi->s_max_batch_time = option;
1324                         break;
1325                 case Opt_min_batch_time:
1326                         if (match_int(&args[0], &option))
1327                                 return 0;
1328                         if (option < 0)
1329                                 return 0;
1330                         sbi->s_min_batch_time = option;
1331                         break;
1332                 case Opt_data_journal:
1333                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1334                         goto datacheck;
1335                 case Opt_data_ordered:
1336                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1337                         goto datacheck;
1338                 case Opt_data_writeback:
1339                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1340                 datacheck:
1341                         if (is_remount) {
1342                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1343                                                 != data_opt) {
1344                                         ext4_msg(sb, KERN_ERR,
1345                                                 "Cannot change data mode on remount");
1346                                         return 0;
1347                                 }
1348                         } else {
1349                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1350                                 sbi->s_mount_opt |= data_opt;
1351                         }
1352                         break;
1353                 case Opt_data_err_abort:
1354                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1355                         break;
1356                 case Opt_data_err_ignore:
1357                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1358                         break;
1359                 case Opt_mb_history_length:
1360                         if (match_int(&args[0], &option))
1361                                 return 0;
1362                         if (option < 0)
1363                                 return 0;
1364                         sbi->s_mb_history_max = option;
1365                         break;
1366 #ifdef CONFIG_QUOTA
1367                 case Opt_usrjquota:
1368                         qtype = USRQUOTA;
1369                         goto set_qf_name;
1370                 case Opt_grpjquota:
1371                         qtype = GRPQUOTA;
1372 set_qf_name:
1373                         if (sb_any_quota_loaded(sb) &&
1374                             !sbi->s_qf_names[qtype]) {
1375                                 ext4_msg(sb, KERN_ERR,
1376                                        "Cannot change journaled "
1377                                        "quota options when quota turned on");
1378                                 return 0;
1379                         }
1380                         qname = match_strdup(&args[0]);
1381                         if (!qname) {
1382                                 ext4_msg(sb, KERN_ERR,
1383                                         "Not enough memory for "
1384                                         "storing quotafile name");
1385                                 return 0;
1386                         }
1387                         if (sbi->s_qf_names[qtype] &&
1388                             strcmp(sbi->s_qf_names[qtype], qname)) {
1389                                 ext4_msg(sb, KERN_ERR,
1390                                         "%s quota file already "
1391                                         "specified", QTYPE2NAME(qtype));
1392                                 kfree(qname);
1393                                 return 0;
1394                         }
1395                         sbi->s_qf_names[qtype] = qname;
1396                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1397                                 ext4_msg(sb, KERN_ERR,
1398                                         "quotafile must be on "
1399                                         "filesystem root");
1400                                 kfree(sbi->s_qf_names[qtype]);
1401                                 sbi->s_qf_names[qtype] = NULL;
1402                                 return 0;
1403                         }
1404                         set_opt(sbi->s_mount_opt, QUOTA);
1405                         break;
1406                 case Opt_offusrjquota:
1407                         qtype = USRQUOTA;
1408                         goto clear_qf_name;
1409                 case Opt_offgrpjquota:
1410                         qtype = GRPQUOTA;
1411 clear_qf_name:
1412                         if (sb_any_quota_loaded(sb) &&
1413                             sbi->s_qf_names[qtype]) {
1414                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1415                                         "journaled quota options when "
1416                                         "quota turned on");
1417                                 return 0;
1418                         }
1419                         /*
1420                          * The space will be released later when all options
1421                          * are confirmed to be correct
1422                          */
1423                         sbi->s_qf_names[qtype] = NULL;
1424                         break;
1425                 case Opt_jqfmt_vfsold:
1426                         qfmt = QFMT_VFS_OLD;
1427                         goto set_qf_format;
1428                 case Opt_jqfmt_vfsv0:
1429                         qfmt = QFMT_VFS_V0;
1430 set_qf_format:
1431                         if (sb_any_quota_loaded(sb) &&
1432                             sbi->s_jquota_fmt != qfmt) {
1433                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1434                                         "journaled quota options when "
1435                                         "quota turned on");
1436                                 return 0;
1437                         }
1438                         sbi->s_jquota_fmt = qfmt;
1439                         break;
1440                 case Opt_quota:
1441                 case Opt_usrquota:
1442                         set_opt(sbi->s_mount_opt, QUOTA);
1443                         set_opt(sbi->s_mount_opt, USRQUOTA);
1444                         break;
1445                 case Opt_grpquota:
1446                         set_opt(sbi->s_mount_opt, QUOTA);
1447                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1448                         break;
1449                 case Opt_noquota:
1450                         if (sb_any_quota_loaded(sb)) {
1451                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1452                                         "options when quota turned on");
1453                                 return 0;
1454                         }
1455                         clear_opt(sbi->s_mount_opt, QUOTA);
1456                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1457                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1458                         break;
1459 #else
1460                 case Opt_quota:
1461                 case Opt_usrquota:
1462                 case Opt_grpquota:
1463                         ext4_msg(sb, KERN_ERR,
1464                                 "quota options not supported");
1465                         break;
1466                 case Opt_usrjquota:
1467                 case Opt_grpjquota:
1468                 case Opt_offusrjquota:
1469                 case Opt_offgrpjquota:
1470                 case Opt_jqfmt_vfsold:
1471                 case Opt_jqfmt_vfsv0:
1472                         ext4_msg(sb, KERN_ERR,
1473                                 "journaled quota options not supported");
1474                         break;
1475                 case Opt_noquota:
1476                         break;
1477 #endif
1478                 case Opt_abort:
1479                         set_opt(sbi->s_mount_opt, ABORT);
1480                         break;
1481                 case Opt_nobarrier:
1482                         clear_opt(sbi->s_mount_opt, BARRIER);
1483                         break;
1484                 case Opt_barrier:
1485                         if (match_int(&args[0], &option)) {
1486                                 set_opt(sbi->s_mount_opt, BARRIER);
1487                                 break;
1488                         }
1489                         if (option)
1490                                 set_opt(sbi->s_mount_opt, BARRIER);
1491                         else
1492                                 clear_opt(sbi->s_mount_opt, BARRIER);
1493                         break;
1494                 case Opt_ignore:
1495                         break;
1496                 case Opt_resize:
1497                         if (!is_remount) {
1498                                 ext4_msg(sb, KERN_ERR,
1499                                         "resize option only available "
1500                                         "for remount");
1501                                 return 0;
1502                         }
1503                         if (match_int(&args[0], &option) != 0)
1504                                 return 0;
1505                         *n_blocks_count = option;
1506                         break;
1507                 case Opt_nobh:
1508                         set_opt(sbi->s_mount_opt, NOBH);
1509                         break;
1510                 case Opt_bh:
1511                         clear_opt(sbi->s_mount_opt, NOBH);
1512                         break;
1513                 case Opt_i_version:
1514                         set_opt(sbi->s_mount_opt, I_VERSION);
1515                         sb->s_flags |= MS_I_VERSION;
1516                         break;
1517                 case Opt_nodelalloc:
1518                         clear_opt(sbi->s_mount_opt, DELALLOC);
1519                         break;
1520                 case Opt_stripe:
1521                         if (match_int(&args[0], &option))
1522                                 return 0;
1523                         if (option < 0)
1524                                 return 0;
1525                         sbi->s_stripe = option;
1526                         break;
1527                 case Opt_delalloc:
1528                         set_opt(sbi->s_mount_opt, DELALLOC);
1529                         break;
1530                 case Opt_block_validity:
1531                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1532                         break;
1533                 case Opt_noblock_validity:
1534                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1535                         break;
1536                 case Opt_inode_readahead_blks:
1537                         if (match_int(&args[0], &option))
1538                                 return 0;
1539                         if (option < 0 || option > (1 << 30))
1540                                 return 0;
1541                         if (!is_power_of_2(option)) {
1542                                 ext4_msg(sb, KERN_ERR,
1543                                          "EXT4-fs: inode_readahead_blks"
1544                                          " must be a power of 2");
1545                                 return 0;
1546                         }
1547                         sbi->s_inode_readahead_blks = option;
1548                         break;
1549                 case Opt_journal_ioprio:
1550                         if (match_int(&args[0], &option))
1551                                 return 0;
1552                         if (option < 0 || option > 7)
1553                                 break;
1554                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1555                                                             option);
1556                         break;
1557                 case Opt_noauto_da_alloc:
1558                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1559                         break;
1560                 case Opt_auto_da_alloc:
1561                         if (match_int(&args[0], &option)) {
1562                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1563                                 break;
1564                         }
1565                         if (option)
1566                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1567                         else
1568                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1569                         break;
1570                 default:
1571                         ext4_msg(sb, KERN_ERR,
1572                                "Unrecognized mount option \"%s\" "
1573                                "or missing value", p);
1574                         return 0;
1575                 }
1576         }
1577 #ifdef CONFIG_QUOTA
1578         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1579                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1580                      sbi->s_qf_names[USRQUOTA])
1581                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1582
1583                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1584                      sbi->s_qf_names[GRPQUOTA])
1585                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1586
1587                 if ((sbi->s_qf_names[USRQUOTA] &&
1588                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1589                     (sbi->s_qf_names[GRPQUOTA] &&
1590                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1591                         ext4_msg(sb, KERN_ERR, "old and new quota "
1592                                         "format mixing");
1593                         return 0;
1594                 }
1595
1596                 if (!sbi->s_jquota_fmt) {
1597                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1598                                         "not specified");
1599                         return 0;
1600                 }
1601         } else {
1602                 if (sbi->s_jquota_fmt) {
1603                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1604                                         "specified with no journaling "
1605                                         "enabled");
1606                         return 0;
1607                 }
1608         }
1609 #endif
1610         return 1;
1611 }
1612
1613 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1614                             int read_only)
1615 {
1616         struct ext4_sb_info *sbi = EXT4_SB(sb);
1617         int res = 0;
1618
1619         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1620                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1621                          "forcing read-only mode");
1622                 res = MS_RDONLY;
1623         }
1624         if (read_only)
1625                 return res;
1626         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1627                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1628                          "running e2fsck is recommended");
1629         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1630                 ext4_msg(sb, KERN_WARNING,
1631                          "warning: mounting fs with errors, "
1632                          "running e2fsck is recommended");
1633         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1634                  le16_to_cpu(es->s_mnt_count) >=
1635                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1636                 ext4_msg(sb, KERN_WARNING,
1637                          "warning: maximal mount count reached, "
1638                          "running e2fsck is recommended");
1639         else if (le32_to_cpu(es->s_checkinterval) &&
1640                 (le32_to_cpu(es->s_lastcheck) +
1641                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1642                 ext4_msg(sb, KERN_WARNING,
1643                          "warning: checktime reached, "
1644                          "running e2fsck is recommended");
1645         if (!sbi->s_journal)
1646                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1647         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1648                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1649         le16_add_cpu(&es->s_mnt_count, 1);
1650         es->s_mtime = cpu_to_le32(get_seconds());
1651         ext4_update_dynamic_rev(sb);
1652         if (sbi->s_journal)
1653                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1654
1655         ext4_commit_super(sb, 1);
1656         if (test_opt(sb, DEBUG))
1657                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1658                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1659                         sb->s_blocksize,
1660                         sbi->s_groups_count,
1661                         EXT4_BLOCKS_PER_GROUP(sb),
1662                         EXT4_INODES_PER_GROUP(sb),
1663                         sbi->s_mount_opt);
1664
1665         if (EXT4_SB(sb)->s_journal) {
1666                 ext4_msg(sb, KERN_INFO, "%s journal on %s",
1667                        EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1668                        "external", EXT4_SB(sb)->s_journal->j_devname);
1669         } else {
1670                 ext4_msg(sb, KERN_INFO, "no journal");
1671         }
1672         return res;
1673 }
1674
1675 static int ext4_fill_flex_info(struct super_block *sb)
1676 {
1677         struct ext4_sb_info *sbi = EXT4_SB(sb);
1678         struct ext4_group_desc *gdp = NULL;
1679         ext4_group_t flex_group_count;
1680         ext4_group_t flex_group;
1681         int groups_per_flex = 0;
1682         size_t size;
1683         int i;
1684
1685         if (!sbi->s_es->s_log_groups_per_flex) {
1686                 sbi->s_log_groups_per_flex = 0;
1687                 return 1;
1688         }
1689
1690         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1691         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1692
1693         /* We allocate both existing and potentially added groups */
1694         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1695                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1696                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1697         size = flex_group_count * sizeof(struct flex_groups);
1698         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1699         if (sbi->s_flex_groups == NULL) {
1700                 sbi->s_flex_groups = vmalloc(size);
1701                 if (sbi->s_flex_groups)
1702                         memset(sbi->s_flex_groups, 0, size);
1703         }
1704         if (sbi->s_flex_groups == NULL) {
1705                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1706                                 "%u flex groups", flex_group_count);
1707                 goto failed;
1708         }
1709
1710         for (i = 0; i < sbi->s_groups_count; i++) {
1711                 gdp = ext4_get_group_desc(sb, i, NULL);
1712
1713                 flex_group = ext4_flex_group(sbi, i);
1714                 atomic_set(&sbi->s_flex_groups[flex_group].free_inodes,
1715                            ext4_free_inodes_count(sb, gdp));
1716                 atomic_set(&sbi->s_flex_groups[flex_group].free_blocks,
1717                            ext4_free_blks_count(sb, gdp));
1718                 atomic_set(&sbi->s_flex_groups[flex_group].used_dirs,
1719                            ext4_used_dirs_count(sb, gdp));
1720         }
1721
1722         return 1;
1723 failed:
1724         return 0;
1725 }
1726
1727 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1728                             struct ext4_group_desc *gdp)
1729 {
1730         __u16 crc = 0;
1731
1732         if (sbi->s_es->s_feature_ro_compat &
1733             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1734                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1735                 __le32 le_group = cpu_to_le32(block_group);
1736
1737                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1738                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1739                 crc = crc16(crc, (__u8 *)gdp, offset);
1740                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1741                 /* for checksum of struct ext4_group_desc do the rest...*/
1742                 if ((sbi->s_es->s_feature_incompat &
1743                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1744                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1745                         crc = crc16(crc, (__u8 *)gdp + offset,
1746                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1747                                         offset);
1748         }
1749
1750         return cpu_to_le16(crc);
1751 }
1752
1753 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1754                                 struct ext4_group_desc *gdp)
1755 {
1756         if ((sbi->s_es->s_feature_ro_compat &
1757              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1758             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1759                 return 0;
1760
1761         return 1;
1762 }
1763
1764 /* Called at mount-time, super-block is locked */
1765 static int ext4_check_descriptors(struct super_block *sb)
1766 {
1767         struct ext4_sb_info *sbi = EXT4_SB(sb);
1768         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1769         ext4_fsblk_t last_block;
1770         ext4_fsblk_t block_bitmap;
1771         ext4_fsblk_t inode_bitmap;
1772         ext4_fsblk_t inode_table;
1773         int flexbg_flag = 0;
1774         ext4_group_t i;
1775
1776         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1777                 flexbg_flag = 1;
1778
1779         ext4_debug("Checking group descriptors");
1780
1781         for (i = 0; i < sbi->s_groups_count; i++) {
1782                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1783
1784                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1785                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1786                 else
1787                         last_block = first_block +
1788                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1789
1790                 block_bitmap = ext4_block_bitmap(sb, gdp);
1791                 if (block_bitmap < first_block || block_bitmap > last_block) {
1792                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1793                                "Block bitmap for group %u not in group "
1794                                "(block %llu)!", i, block_bitmap);
1795                         return 0;
1796                 }
1797                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1798                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1799                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1800                                "Inode bitmap for group %u not in group "
1801                                "(block %llu)!", i, inode_bitmap);
1802                         return 0;
1803                 }
1804                 inode_table = ext4_inode_table(sb, gdp);
1805                 if (inode_table < first_block ||
1806                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1807                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1808                                "Inode table for group %u not in group "
1809                                "(block %llu)!", i, inode_table);
1810                         return 0;
1811                 }
1812                 ext4_lock_group(sb, i);
1813                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1814                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1815                                  "Checksum for group %u failed (%u!=%u)",
1816                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1817                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1818                         if (!(sb->s_flags & MS_RDONLY)) {
1819                                 ext4_unlock_group(sb, i);
1820                                 return 0;
1821                         }
1822                 }
1823                 ext4_unlock_group(sb, i);
1824                 if (!flexbg_flag)
1825                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1826         }
1827
1828         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1829         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1830         return 1;
1831 }
1832
1833 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1834  * the superblock) which were deleted from all directories, but held open by
1835  * a process at the time of a crash.  We walk the list and try to delete these
1836  * inodes at recovery time (only with a read-write filesystem).
1837  *
1838  * In order to keep the orphan inode chain consistent during traversal (in
1839  * case of crash during recovery), we link each inode into the superblock
1840  * orphan list_head and handle it the same way as an inode deletion during
1841  * normal operation (which journals the operations for us).
1842  *
1843  * We only do an iget() and an iput() on each inode, which is very safe if we
1844  * accidentally point at an in-use or already deleted inode.  The worst that
1845  * can happen in this case is that we get a "bit already cleared" message from
1846  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1847  * e2fsck was run on this filesystem, and it must have already done the orphan
1848  * inode cleanup for us, so we can safely abort without any further action.
1849  */
1850 static void ext4_orphan_cleanup(struct super_block *sb,
1851                                 struct ext4_super_block *es)
1852 {
1853         unsigned int s_flags = sb->s_flags;
1854         int nr_orphans = 0, nr_truncates = 0;
1855 #ifdef CONFIG_QUOTA
1856         int i;
1857 #endif
1858         if (!es->s_last_orphan) {
1859                 jbd_debug(4, "no orphan inodes to clean up\n");
1860                 return;
1861         }
1862
1863         if (bdev_read_only(sb->s_bdev)) {
1864                 ext4_msg(sb, KERN_ERR, "write access "
1865                         "unavailable, skipping orphan cleanup");
1866                 return;
1867         }
1868
1869         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1870                 if (es->s_last_orphan)
1871                         jbd_debug(1, "Errors on filesystem, "
1872                                   "clearing orphan list.\n");
1873                 es->s_last_orphan = 0;
1874                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1875                 return;
1876         }
1877
1878         if (s_flags & MS_RDONLY) {
1879                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1880                 sb->s_flags &= ~MS_RDONLY;
1881         }
1882 #ifdef CONFIG_QUOTA
1883         /* Needed for iput() to work correctly and not trash data */
1884         sb->s_flags |= MS_ACTIVE;
1885         /* Turn on quotas so that they are updated correctly */
1886         for (i = 0; i < MAXQUOTAS; i++) {
1887                 if (EXT4_SB(sb)->s_qf_names[i]) {
1888                         int ret = ext4_quota_on_mount(sb, i);
1889                         if (ret < 0)
1890                                 ext4_msg(sb, KERN_ERR,
1891                                         "Cannot turn on journaled "
1892                                         "quota: error %d", ret);
1893                 }
1894         }
1895 #endif
1896
1897         while (es->s_last_orphan) {
1898                 struct inode *inode;
1899
1900                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1901                 if (IS_ERR(inode)) {
1902                         es->s_last_orphan = 0;
1903                         break;
1904                 }
1905
1906                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1907                 vfs_dq_init(inode);
1908                 if (inode->i_nlink) {
1909                         ext4_msg(sb, KERN_DEBUG,
1910                                 "%s: truncating inode %lu to %lld bytes",
1911                                 __func__, inode->i_ino, inode->i_size);
1912                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1913                                   inode->i_ino, inode->i_size);
1914                         ext4_truncate(inode);
1915                         nr_truncates++;
1916                 } else {
1917                         ext4_msg(sb, KERN_DEBUG,
1918                                 "%s: deleting unreferenced inode %lu",
1919                                 __func__, inode->i_ino);
1920                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1921                                   inode->i_ino);
1922                         nr_orphans++;
1923                 }
1924                 iput(inode);  /* The delete magic happens here! */
1925         }
1926
1927 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1928
1929         if (nr_orphans)
1930                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1931                        PLURAL(nr_orphans));
1932         if (nr_truncates)
1933                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1934                        PLURAL(nr_truncates));
1935 #ifdef CONFIG_QUOTA
1936         /* Turn quotas off */
1937         for (i = 0; i < MAXQUOTAS; i++) {
1938                 if (sb_dqopt(sb)->files[i])
1939                         vfs_quota_off(sb, i, 0);
1940         }
1941 #endif
1942         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1943 }
1944
1945 /*
1946  * Maximal extent format file size.
1947  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1948  * extent format containers, within a sector_t, and within i_blocks
1949  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1950  * so that won't be a limiting factor.
1951  *
1952  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1953  */
1954 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1955 {
1956         loff_t res;
1957         loff_t upper_limit = MAX_LFS_FILESIZE;
1958
1959         /* small i_blocks in vfs inode? */
1960         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1961                 /*
1962                  * CONFIG_LBD is not enabled implies the inode
1963                  * i_block represent total blocks in 512 bytes
1964                  * 32 == size of vfs inode i_blocks * 8
1965                  */
1966                 upper_limit = (1LL << 32) - 1;
1967
1968                 /* total blocks in file system block size */
1969                 upper_limit >>= (blkbits - 9);
1970                 upper_limit <<= blkbits;
1971         }
1972
1973         /* 32-bit extent-start container, ee_block */
1974         res = 1LL << 32;
1975         res <<= blkbits;
1976         res -= 1;
1977
1978         /* Sanity check against vm- & vfs- imposed limits */
1979         if (res > upper_limit)
1980                 res = upper_limit;
1981
1982         return res;
1983 }
1984
1985 /*
1986  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1987  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1988  * We need to be 1 filesystem block less than the 2^48 sector limit.
1989  */
1990 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
1991 {
1992         loff_t res = EXT4_NDIR_BLOCKS;
1993         int meta_blocks;
1994         loff_t upper_limit;
1995         /* This is calculated to be the largest file size for a dense, block
1996          * mapped file such that the file's total number of 512-byte sectors,
1997          * including data and all indirect blocks, does not exceed (2^48 - 1).
1998          *
1999          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2000          * number of 512-byte sectors of the file.
2001          */
2002
2003         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2004                 /*
2005                  * !has_huge_files or CONFIG_LBD not enabled implies that
2006                  * the inode i_block field represents total file blocks in
2007                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2008                  */
2009                 upper_limit = (1LL << 32) - 1;
2010
2011                 /* total blocks in file system block size */
2012                 upper_limit >>= (bits - 9);
2013
2014         } else {
2015                 /*
2016                  * We use 48 bit ext4_inode i_blocks
2017                  * With EXT4_HUGE_FILE_FL set the i_blocks
2018                  * represent total number of blocks in
2019                  * file system block size
2020                  */
2021                 upper_limit = (1LL << 48) - 1;
2022
2023         }
2024
2025         /* indirect blocks */
2026         meta_blocks = 1;
2027         /* double indirect blocks */
2028         meta_blocks += 1 + (1LL << (bits-2));
2029         /* tripple indirect blocks */
2030         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2031
2032         upper_limit -= meta_blocks;
2033         upper_limit <<= bits;
2034
2035         res += 1LL << (bits-2);
2036         res += 1LL << (2*(bits-2));
2037         res += 1LL << (3*(bits-2));
2038         res <<= bits;
2039         if (res > upper_limit)
2040                 res = upper_limit;
2041
2042         if (res > MAX_LFS_FILESIZE)
2043                 res = MAX_LFS_FILESIZE;
2044
2045         return res;
2046 }
2047
2048 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2049                                    ext4_fsblk_t logical_sb_block, int nr)
2050 {
2051         struct ext4_sb_info *sbi = EXT4_SB(sb);
2052         ext4_group_t bg, first_meta_bg;
2053         int has_super = 0;
2054
2055         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2056
2057         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2058             nr < first_meta_bg)
2059                 return logical_sb_block + nr + 1;
2060         bg = sbi->s_desc_per_block * nr;
2061         if (ext4_bg_has_super(sb, bg))
2062                 has_super = 1;
2063
2064         return (has_super + ext4_group_first_block_no(sb, bg));
2065 }
2066
2067 /**
2068  * ext4_get_stripe_size: Get the stripe size.
2069  * @sbi: In memory super block info
2070  *
2071  * If we have specified it via mount option, then
2072  * use the mount option value. If the value specified at mount time is
2073  * greater than the blocks per group use the super block value.
2074  * If the super block value is greater than blocks per group return 0.
2075  * Allocator needs it be less than blocks per group.
2076  *
2077  */
2078 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2079 {
2080         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2081         unsigned long stripe_width =
2082                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2083
2084         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2085                 return sbi->s_stripe;
2086
2087         if (stripe_width <= sbi->s_blocks_per_group)
2088                 return stripe_width;
2089
2090         if (stride <= sbi->s_blocks_per_group)
2091                 return stride;
2092
2093         return 0;
2094 }
2095
2096 /* sysfs supprt */
2097
2098 struct ext4_attr {
2099         struct attribute attr;
2100         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2101         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2102                          const char *, size_t);
2103         int offset;
2104 };
2105
2106 static int parse_strtoul(const char *buf,
2107                 unsigned long max, unsigned long *value)
2108 {
2109         char *endp;
2110
2111         while (*buf && isspace(*buf))
2112                 buf++;
2113         *value = simple_strtoul(buf, &endp, 0);
2114         while (*endp && isspace(*endp))
2115                 endp++;
2116         if (*endp || *value > max)
2117                 return -EINVAL;
2118
2119         return 0;
2120 }
2121
2122 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2123                                               struct ext4_sb_info *sbi,
2124                                               char *buf)
2125 {
2126         return snprintf(buf, PAGE_SIZE, "%llu\n",
2127                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2128 }
2129
2130 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2131                                          struct ext4_sb_info *sbi, char *buf)
2132 {
2133         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2134
2135         return snprintf(buf, PAGE_SIZE, "%lu\n",
2136                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2137                          sbi->s_sectors_written_start) >> 1);
2138 }
2139
2140 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2141                                           struct ext4_sb_info *sbi, char *buf)
2142 {
2143         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2144
2145         return snprintf(buf, PAGE_SIZE, "%llu\n",
2146                         sbi->s_kbytes_written +
2147                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2148                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2149 }
2150
2151 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2152                                           struct ext4_sb_info *sbi,
2153                                           const char *buf, size_t count)
2154 {
2155         unsigned long t;
2156
2157         if (parse_strtoul(buf, 0x40000000, &t))
2158                 return -EINVAL;
2159
2160         if (!is_power_of_2(t))
2161                 return -EINVAL;
2162
2163         sbi->s_inode_readahead_blks = t;
2164         return count;
2165 }
2166
2167 static ssize_t sbi_ui_show(struct ext4_attr *a,
2168                            struct ext4_sb_info *sbi, char *buf)
2169 {
2170         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2171
2172         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2173 }
2174
2175 static ssize_t sbi_ui_store(struct ext4_attr *a,
2176                             struct ext4_sb_info *sbi,
2177                             const char *buf, size_t count)
2178 {
2179         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2180         unsigned long t;
2181
2182         if (parse_strtoul(buf, 0xffffffff, &t))
2183                 return -EINVAL;
2184         *ui = t;
2185         return count;
2186 }
2187
2188 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2189 static struct ext4_attr ext4_attr_##_name = {                   \
2190         .attr = {.name = __stringify(_name), .mode = _mode },   \
2191         .show   = _show,                                        \
2192         .store  = _store,                                       \
2193         .offset = offsetof(struct ext4_sb_info, _elname),       \
2194 }
2195 #define EXT4_ATTR(name, mode, show, store) \
2196 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2197
2198 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2199 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2200 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2201         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2202 #define ATTR_LIST(name) &ext4_attr_##name.attr
2203
2204 EXT4_RO_ATTR(delayed_allocation_blocks);
2205 EXT4_RO_ATTR(session_write_kbytes);
2206 EXT4_RO_ATTR(lifetime_write_kbytes);
2207 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2208                  inode_readahead_blks_store, s_inode_readahead_blks);
2209 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2210 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2211 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2212 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2213 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2214 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2215
2216 static struct attribute *ext4_attrs[] = {
2217         ATTR_LIST(delayed_allocation_blocks),
2218         ATTR_LIST(session_write_kbytes),
2219         ATTR_LIST(lifetime_write_kbytes),
2220         ATTR_LIST(inode_readahead_blks),
2221         ATTR_LIST(mb_stats),
2222         ATTR_LIST(mb_max_to_scan),
2223         ATTR_LIST(mb_min_to_scan),
2224         ATTR_LIST(mb_order2_req),
2225         ATTR_LIST(mb_stream_req),
2226         ATTR_LIST(mb_group_prealloc),
2227         NULL,
2228 };
2229
2230 static ssize_t ext4_attr_show(struct kobject *kobj,
2231                               struct attribute *attr, char *buf)
2232 {
2233         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2234                                                 s_kobj);
2235         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2236
2237         return a->show ? a->show(a, sbi, buf) : 0;
2238 }
2239
2240 static ssize_t ext4_attr_store(struct kobject *kobj,
2241                                struct attribute *attr,
2242                                const char *buf, size_t len)
2243 {
2244         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2245                                                 s_kobj);
2246         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2247
2248         return a->store ? a->store(a, sbi, buf, len) : 0;
2249 }
2250
2251 static void ext4_sb_release(struct kobject *kobj)
2252 {
2253         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2254                                                 s_kobj);
2255         complete(&sbi->s_kobj_unregister);
2256 }
2257
2258
2259 static struct sysfs_ops ext4_attr_ops = {
2260         .show   = ext4_attr_show,
2261         .store  = ext4_attr_store,
2262 };
2263
2264 static struct kobj_type ext4_ktype = {
2265         .default_attrs  = ext4_attrs,
2266         .sysfs_ops      = &ext4_attr_ops,
2267         .release        = ext4_sb_release,
2268 };
2269
2270 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2271                                 __releases(kernel_lock)
2272                                 __acquires(kernel_lock)
2273 {
2274         struct buffer_head *bh;
2275         struct ext4_super_block *es = NULL;
2276         struct ext4_sb_info *sbi;
2277         ext4_fsblk_t block;
2278         ext4_fsblk_t sb_block = get_sb_block(&data);
2279         ext4_fsblk_t logical_sb_block;
2280         unsigned long offset = 0;
2281         unsigned long journal_devnum = 0;
2282         unsigned long def_mount_opts;
2283         struct inode *root;
2284         char *cp;
2285         const char *descr;
2286         int ret = -EINVAL;
2287         int blocksize;
2288         unsigned int db_count;
2289         unsigned int i;
2290         int needs_recovery, has_huge_files;
2291         int features;
2292         __u64 blocks_count;
2293         int err;
2294         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2295
2296         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2297         if (!sbi)
2298                 return -ENOMEM;
2299
2300         sbi->s_blockgroup_lock =
2301                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2302         if (!sbi->s_blockgroup_lock) {
2303                 kfree(sbi);
2304                 return -ENOMEM;
2305         }
2306         sb->s_fs_info = sbi;
2307         sbi->s_mount_opt = 0;
2308         sbi->s_resuid = EXT4_DEF_RESUID;
2309         sbi->s_resgid = EXT4_DEF_RESGID;
2310         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2311         sbi->s_sb_block = sb_block;
2312         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2313                                                       sectors[1]);
2314
2315         unlock_kernel();
2316
2317         /* Cleanup superblock name */
2318         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2319                 *cp = '!';
2320
2321         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2322         if (!blocksize) {
2323                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2324                 goto out_fail;
2325         }
2326
2327         /*
2328          * The ext4 superblock will not be buffer aligned for other than 1kB
2329          * block sizes.  We need to calculate the offset from buffer start.
2330          */
2331         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2332                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2333                 offset = do_div(logical_sb_block, blocksize);
2334         } else {
2335                 logical_sb_block = sb_block;
2336         }
2337
2338         if (!(bh = sb_bread(sb, logical_sb_block))) {
2339                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2340                 goto out_fail;
2341         }
2342         /*
2343          * Note: s_es must be initialized as soon as possible because
2344          *       some ext4 macro-instructions depend on its value
2345          */
2346         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2347         sbi->s_es = es;
2348         sb->s_magic = le16_to_cpu(es->s_magic);
2349         if (sb->s_magic != EXT4_SUPER_MAGIC)
2350                 goto cantfind_ext4;
2351         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2352
2353         /* Set defaults before we parse the mount options */
2354         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2355         if (def_mount_opts & EXT4_DEFM_DEBUG)
2356                 set_opt(sbi->s_mount_opt, DEBUG);
2357         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2358                 set_opt(sbi->s_mount_opt, GRPID);
2359         if (def_mount_opts & EXT4_DEFM_UID16)
2360                 set_opt(sbi->s_mount_opt, NO_UID32);
2361 #ifdef CONFIG_EXT4_FS_XATTR
2362         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2363                 set_opt(sbi->s_mount_opt, XATTR_USER);
2364 #endif
2365 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2366         if (def_mount_opts & EXT4_DEFM_ACL)
2367                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2368 #endif
2369         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2370                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2371         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2372                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2373         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2374                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2375
2376         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2377                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2378         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2379                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2380         else
2381                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2382
2383         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2384         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2385         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2386         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2387         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2388         sbi->s_mb_history_max = default_mb_history_length;
2389
2390         set_opt(sbi->s_mount_opt, BARRIER);
2391
2392         /*
2393          * enable delayed allocation by default
2394          * Use -o nodelalloc to turn it off
2395          */
2396         set_opt(sbi->s_mount_opt, DELALLOC);
2397
2398         if (!parse_options((char *) data, sb, &journal_devnum,
2399                            &journal_ioprio, NULL, 0))
2400                 goto failed_mount;
2401
2402         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2403                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2404
2405         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2406             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2407              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2408              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2409                 ext4_msg(sb, KERN_WARNING,
2410                        "feature flags set on rev 0 fs, "
2411                        "running e2fsck is recommended");
2412
2413         /*
2414          * Check feature flags regardless of the revision level, since we
2415          * previously didn't change the revision level when setting the flags,
2416          * so there is a chance incompat flags are set on a rev 0 filesystem.
2417          */
2418         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2419         if (features) {
2420                 ext4_msg(sb, KERN_ERR,
2421                         "Couldn't mount because of "
2422                         "unsupported optional features (%x)",
2423                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2424                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2425                 goto failed_mount;
2426         }
2427         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2428         if (!(sb->s_flags & MS_RDONLY) && features) {
2429                 ext4_msg(sb, KERN_ERR,
2430                         "Couldn't mount RDWR because of "
2431                         "unsupported optional features (%x)",
2432                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2433                         ~EXT4_FEATURE_RO_COMPAT_SUPP));
2434                 goto failed_mount;
2435         }
2436         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2437                                     EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2438         if (has_huge_files) {
2439                 /*
2440                  * Large file size enabled file system can only be
2441                  * mount if kernel is build with CONFIG_LBD
2442                  */
2443                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2444                                 !(sb->s_flags & MS_RDONLY)) {
2445                         ext4_msg(sb, KERN_ERR, "Filesystem with huge "
2446                                         "files cannot be mounted read-write "
2447                                         "without CONFIG_LBD");
2448                         goto failed_mount;
2449                 }
2450         }
2451         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2452
2453         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2454             blocksize > EXT4_MAX_BLOCK_SIZE) {
2455                 ext4_msg(sb, KERN_ERR,
2456                        "Unsupported filesystem blocksize %d", blocksize);
2457                 goto failed_mount;
2458         }
2459
2460         if (sb->s_blocksize != blocksize) {
2461                 /* Validate the filesystem blocksize */
2462                 if (!sb_set_blocksize(sb, blocksize)) {
2463                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2464                                         blocksize);
2465                         goto failed_mount;
2466                 }
2467
2468                 brelse(bh);
2469                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2470                 offset = do_div(logical_sb_block, blocksize);
2471                 bh = sb_bread(sb, logical_sb_block);
2472                 if (!bh) {
2473                         ext4_msg(sb, KERN_ERR,
2474                                "Can't read superblock on 2nd try");
2475                         goto failed_mount;
2476                 }
2477                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2478                 sbi->s_es = es;
2479                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2480                         ext4_msg(sb, KERN_ERR,
2481                                "Magic mismatch, very weird!");
2482                         goto failed_mount;
2483                 }
2484         }
2485
2486         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2487                                                       has_huge_files);
2488         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2489
2490         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2491                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2492                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2493         } else {
2494                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2495                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2496                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2497                     (!is_power_of_2(sbi->s_inode_size)) ||
2498                     (sbi->s_inode_size > blocksize)) {
2499                         ext4_msg(sb, KERN_ERR,
2500                                "unsupported inode size: %d",
2501                                sbi->s_inode_size);
2502                         goto failed_mount;
2503                 }
2504                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2505                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2506         }
2507
2508         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2509         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2510                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2511                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2512                     !is_power_of_2(sbi->s_desc_size)) {
2513                         ext4_msg(sb, KERN_ERR,
2514                                "unsupported descriptor size %lu",
2515                                sbi->s_desc_size);
2516                         goto failed_mount;
2517                 }
2518         } else
2519                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2520
2521         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2522         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2523         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2524                 goto cantfind_ext4;
2525
2526         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2527         if (sbi->s_inodes_per_block == 0)
2528                 goto cantfind_ext4;
2529         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2530                                         sbi->s_inodes_per_block;
2531         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2532         sbi->s_sbh = bh;
2533         sbi->s_mount_state = le16_to_cpu(es->s_state);
2534         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2535         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2536
2537         for (i = 0; i < 4; i++)
2538                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2539         sbi->s_def_hash_version = es->s_def_hash_version;
2540         i = le32_to_cpu(es->s_flags);
2541         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2542                 sbi->s_hash_unsigned = 3;
2543         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2544 #ifdef __CHAR_UNSIGNED__
2545                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2546                 sbi->s_hash_unsigned = 3;
2547 #else
2548                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2549 #endif
2550                 sb->s_dirt = 1;
2551         }
2552
2553         if (sbi->s_blocks_per_group > blocksize * 8) {
2554                 ext4_msg(sb, KERN_ERR,
2555                        "#blocks per group too big: %lu",
2556                        sbi->s_blocks_per_group);
2557                 goto failed_mount;
2558         }
2559         if (sbi->s_inodes_per_group > blocksize * 8) {
2560                 ext4_msg(sb, KERN_ERR,
2561                        "#inodes per group too big: %lu",
2562                        sbi->s_inodes_per_group);
2563                 goto failed_mount;
2564         }
2565
2566         if (ext4_blocks_count(es) >
2567                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2568                 ext4_msg(sb, KERN_ERR, "filesystem"
2569                         " too large to mount safely");
2570                 if (sizeof(sector_t) < 8)
2571                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBD not enabled");
2572                 goto failed_mount;
2573         }
2574
2575         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2576                 goto cantfind_ext4;
2577
2578         /* check blocks count against device size */
2579         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2580         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2581                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2582                        "exceeds size of device (%llu blocks)",
2583                        ext4_blocks_count(es), blocks_count);
2584                 goto failed_mount;
2585         }
2586
2587         /*
2588          * It makes no sense for the first data block to be beyond the end
2589          * of the filesystem.
2590          */
2591         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2592                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2593                          "block %u is beyond end of filesystem (%llu)",
2594                          le32_to_cpu(es->s_first_data_block),
2595                          ext4_blocks_count(es));
2596                 goto failed_mount;
2597         }
2598         blocks_count = (ext4_blocks_count(es) -
2599                         le32_to_cpu(es->s_first_data_block) +
2600                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2601         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2602         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2603                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2604                        "(block count %llu, first data block %u, "
2605                        "blocks per group %lu)", sbi->s_groups_count,
2606                        ext4_blocks_count(es),
2607                        le32_to_cpu(es->s_first_data_block),
2608                        EXT4_BLOCKS_PER_GROUP(sb));
2609                 goto failed_mount;
2610         }
2611         sbi->s_groups_count = blocks_count;
2612         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2613                    EXT4_DESC_PER_BLOCK(sb);
2614         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2615                                     GFP_KERNEL);
2616         if (sbi->s_group_desc == NULL) {
2617                 ext4_msg(sb, KERN_ERR, "not enough memory");
2618                 goto failed_mount;
2619         }
2620
2621 #ifdef CONFIG_PROC_FS
2622         if (ext4_proc_root)
2623                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2624 #endif
2625
2626         bgl_lock_init(sbi->s_blockgroup_lock);
2627
2628         for (i = 0; i < db_count; i++) {
2629                 block = descriptor_loc(sb, logical_sb_block, i);
2630                 sbi->s_group_desc[i] = sb_bread(sb, block);
2631                 if (!sbi->s_group_desc[i]) {
2632                         ext4_msg(sb, KERN_ERR,
2633                                "can't read group descriptor %d", i);
2634                         db_count = i;
2635                         goto failed_mount2;
2636                 }
2637         }
2638         if (!ext4_check_descriptors(sb)) {
2639                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2640                 goto failed_mount2;
2641         }
2642         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2643                 if (!ext4_fill_flex_info(sb)) {
2644                         ext4_msg(sb, KERN_ERR,
2645                                "unable to initialize "
2646                                "flex_bg meta info!");
2647                         goto failed_mount2;
2648                 }
2649
2650         sbi->s_gdb_count = db_count;
2651         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2652         spin_lock_init(&sbi->s_next_gen_lock);
2653
2654         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2655                         ext4_count_free_blocks(sb));
2656         if (!err) {
2657                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2658                                 ext4_count_free_inodes(sb));
2659         }
2660         if (!err) {
2661                 err = percpu_counter_init(&sbi->s_dirs_counter,
2662                                 ext4_count_dirs(sb));
2663         }
2664         if (!err) {
2665                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2666         }
2667         if (err) {
2668                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2669                 goto failed_mount3;
2670         }
2671
2672         sbi->s_stripe = ext4_get_stripe_size(sbi);
2673
2674         /*
2675          * set up enough so that it can read an inode
2676          */
2677         if (!test_opt(sb, NOLOAD) &&
2678             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2679                 sb->s_op = &ext4_sops;
2680         else
2681                 sb->s_op = &ext4_nojournal_sops;
2682         sb->s_export_op = &ext4_export_ops;
2683         sb->s_xattr = ext4_xattr_handlers;
2684 #ifdef CONFIG_QUOTA
2685         sb->s_qcop = &ext4_qctl_operations;
2686         sb->dq_op = &ext4_quota_operations;
2687 #endif
2688         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2689         mutex_init(&sbi->s_orphan_lock);
2690         mutex_init(&sbi->s_resize_lock);
2691
2692         sb->s_root = NULL;
2693
2694         needs_recovery = (es->s_last_orphan != 0 ||
2695                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2696                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2697
2698         /*
2699          * The first inode we look at is the journal inode.  Don't try
2700          * root first: it may be modified in the journal!
2701          */
2702         if (!test_opt(sb, NOLOAD) &&
2703             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2704                 if (ext4_load_journal(sb, es, journal_devnum))
2705                         goto failed_mount3;
2706                 if (!(sb->s_flags & MS_RDONLY) &&
2707                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2708                         ext4_msg(sb, KERN_CRIT, "error: "
2709                                "ext4_fill_super: Journal transaction "
2710                                "%u is corrupt",
2711                                EXT4_SB(sb)->s_journal->j_failed_commit);
2712                         if (test_opt(sb, ERRORS_RO)) {
2713                                 ext4_msg(sb, KERN_CRIT,
2714                                        "Mounting filesystem read-only");
2715                                 sb->s_flags |= MS_RDONLY;
2716                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2717                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2718                         }
2719                         if (test_opt(sb, ERRORS_PANIC)) {
2720                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2721                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2722                                 ext4_commit_super(sb, 1);
2723                                 goto failed_mount4;
2724                         }
2725                 }
2726         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2727               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2728                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2729                        "suppressed and not mounted read-only");
2730                 goto failed_mount4;
2731         } else {
2732                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2733                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2734                 sbi->s_journal = NULL;
2735                 needs_recovery = 0;
2736                 goto no_journal;
2737         }
2738
2739         if (ext4_blocks_count(es) > 0xffffffffULL &&
2740             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2741                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2742                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2743                 goto failed_mount4;
2744         }
2745
2746         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2747                 jbd2_journal_set_features(sbi->s_journal,
2748                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2749                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2750         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2751                 jbd2_journal_set_features(sbi->s_journal,
2752                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2753                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2754                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2755         } else {
2756                 jbd2_journal_clear_features(sbi->s_journal,
2757                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2758                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2759         }
2760
2761         /* We have now updated the journal if required, so we can
2762          * validate the data journaling mode. */
2763         switch (test_opt(sb, DATA_FLAGS)) {
2764         case 0:
2765                 /* No mode set, assume a default based on the journal
2766                  * capabilities: ORDERED_DATA if the journal can
2767                  * cope, else JOURNAL_DATA
2768                  */
2769                 if (jbd2_journal_check_available_features
2770                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2771                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2772                 else
2773                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2774                 break;
2775
2776         case EXT4_MOUNT_ORDERED_DATA:
2777         case EXT4_MOUNT_WRITEBACK_DATA:
2778                 if (!jbd2_journal_check_available_features
2779                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2780                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2781                                "requested data journaling mode");
2782                         goto failed_mount4;
2783                 }
2784         default:
2785                 break;
2786         }
2787         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2788
2789 no_journal:
2790
2791         if (test_opt(sb, NOBH)) {
2792                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2793                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2794                                 "its supported only with writeback mode");
2795                         clear_opt(sbi->s_mount_opt, NOBH);
2796                 }
2797         }
2798         /*
2799          * The jbd2_journal_load will have done any necessary log recovery,
2800          * so we can safely mount the rest of the filesystem now.
2801          */
2802
2803         root = ext4_iget(sb, EXT4_ROOT_INO);
2804         if (IS_ERR(root)) {
2805                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2806                 ret = PTR_ERR(root);
2807                 goto failed_mount4;
2808         }
2809         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2810                 iput(root);
2811                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2812                 goto failed_mount4;
2813         }
2814         sb->s_root = d_alloc_root(root);
2815         if (!sb->s_root) {
2816                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2817                 iput(root);
2818                 ret = -ENOMEM;
2819                 goto failed_mount4;
2820         }
2821
2822         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2823
2824         /* determine the minimum size of new large inodes, if present */
2825         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2826                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2827                                                      EXT4_GOOD_OLD_INODE_SIZE;
2828                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2829                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2830                         if (sbi->s_want_extra_isize <
2831                             le16_to_cpu(es->s_want_extra_isize))
2832                                 sbi->s_want_extra_isize =
2833                                         le16_to_cpu(es->s_want_extra_isize);
2834                         if (sbi->s_want_extra_isize <
2835                             le16_to_cpu(es->s_min_extra_isize))
2836                                 sbi->s_want_extra_isize =
2837                                         le16_to_cpu(es->s_min_extra_isize);
2838                 }
2839         }
2840         /* Check if enough inode space is available */
2841         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2842                                                         sbi->s_inode_size) {
2843                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2844                                                        EXT4_GOOD_OLD_INODE_SIZE;
2845                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2846                          "available");
2847         }
2848
2849         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2850                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2851                          "requested data journaling mode");
2852                 clear_opt(sbi->s_mount_opt, DELALLOC);
2853         } else if (test_opt(sb, DELALLOC))
2854                 ext4_msg(sb, KERN_INFO, "delayed allocation enabled");
2855
2856         err = ext4_setup_system_zone(sb);
2857         if (err) {
2858                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2859                          "zone (%d)\n", err);
2860                 goto failed_mount4;
2861         }
2862
2863         ext4_ext_init(sb);
2864         err = ext4_mb_init(sb, needs_recovery);
2865         if (err) {
2866                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2867                          err);
2868                 goto failed_mount4;
2869         }
2870
2871         sbi->s_kobj.kset = ext4_kset;
2872         init_completion(&sbi->s_kobj_unregister);
2873         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2874                                    "%s", sb->s_id);
2875         if (err) {
2876                 ext4_mb_release(sb);
2877                 ext4_ext_release(sb);
2878                 goto failed_mount4;
2879         };
2880
2881         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2882         ext4_orphan_cleanup(sb, es);
2883         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2884         if (needs_recovery) {
2885                 ext4_msg(sb, KERN_INFO, "recovery complete");
2886                 ext4_mark_recovery_complete(sb, es);
2887         }
2888         if (EXT4_SB(sb)->s_journal) {
2889                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2890                         descr = " journalled data mode";
2891                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2892                         descr = " ordered data mode";
2893                 else
2894                         descr = " writeback data mode";
2895         } else
2896                 descr = "out journal";
2897
2898         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2899
2900         lock_kernel();
2901         return 0;
2902
2903 cantfind_ext4:
2904         if (!silent)
2905                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2906         goto failed_mount;
2907
2908 failed_mount4:
2909         ext4_msg(sb, KERN_ERR, "mount failed");
2910         ext4_release_system_zone(sb);
2911         if (sbi->s_journal) {
2912                 jbd2_journal_destroy(sbi->s_journal);
2913                 sbi->s_journal = NULL;
2914         }
2915 failed_mount3:
2916         if (sbi->s_flex_groups) {
2917                 if (is_vmalloc_addr(sbi->s_flex_groups))
2918                         vfree(sbi->s_flex_groups);
2919                 else
2920                         kfree(sbi->s_flex_groups);
2921         }
2922         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2923         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2924         percpu_counter_destroy(&sbi->s_dirs_counter);
2925         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2926 failed_mount2:
2927         for (i = 0; i < db_count; i++)
2928                 brelse(sbi->s_group_desc[i]);
2929         kfree(sbi->s_group_desc);
2930 failed_mount:
2931         if (sbi->s_proc) {
2932                 remove_proc_entry(sb->s_id, ext4_proc_root);
2933         }
2934 #ifdef CONFIG_QUOTA
2935         for (i = 0; i < MAXQUOTAS; i++)
2936                 kfree(sbi->s_qf_names[i]);
2937 #endif
2938         ext4_blkdev_remove(sbi);
2939         brelse(bh);
2940 out_fail:
2941         sb->s_fs_info = NULL;
2942         kfree(sbi->s_blockgroup_lock);
2943         kfree(sbi);
2944         lock_kernel();
2945         return ret;
2946 }
2947
2948 /*
2949  * Setup any per-fs journal parameters now.  We'll do this both on
2950  * initial mount, once the journal has been initialised but before we've
2951  * done any recovery; and again on any subsequent remount.
2952  */
2953 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2954 {
2955         struct ext4_sb_info *sbi = EXT4_SB(sb);
2956
2957         journal->j_commit_interval = sbi->s_commit_interval;
2958         journal->j_min_batch_time = sbi->s_min_batch_time;
2959         journal->j_max_batch_time = sbi->s_max_batch_time;
2960
2961         spin_lock(&journal->j_state_lock);
2962         if (test_opt(sb, BARRIER))
2963                 journal->j_flags |= JBD2_BARRIER;
2964         else
2965                 journal->j_flags &= ~JBD2_BARRIER;
2966         if (test_opt(sb, DATA_ERR_ABORT))
2967                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
2968         else
2969                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
2970         spin_unlock(&journal->j_state_lock);
2971 }
2972
2973 static journal_t *ext4_get_journal(struct super_block *sb,
2974                                    unsigned int journal_inum)
2975 {
2976         struct inode *journal_inode;
2977         journal_t *journal;
2978
2979         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2980
2981         /* First, test for the existence of a valid inode on disk.  Bad
2982          * things happen if we iget() an unused inode, as the subsequent
2983          * iput() will try to delete it. */
2984
2985         journal_inode = ext4_iget(sb, journal_inum);
2986         if (IS_ERR(journal_inode)) {
2987                 ext4_msg(sb, KERN_ERR, "no journal found");
2988                 return NULL;
2989         }
2990         if (!journal_inode->i_nlink) {
2991                 make_bad_inode(journal_inode);
2992                 iput(journal_inode);
2993                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
2994                 return NULL;
2995         }
2996
2997         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
2998                   journal_inode, journal_inode->i_size);
2999         if (!S_ISREG(journal_inode->i_mode)) {
3000                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3001                 iput(journal_inode);
3002                 return NULL;
3003         }
3004
3005         journal = jbd2_journal_init_inode(journal_inode);
3006         if (!journal) {
3007                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3008                 iput(journal_inode);
3009                 return NULL;
3010         }
3011         journal->j_private = sb;
3012         ext4_init_journal_params(sb, journal);
3013         return journal;
3014 }
3015
3016 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3017                                        dev_t j_dev)
3018 {
3019         struct buffer_head *bh;
3020         journal_t *journal;
3021         ext4_fsblk_t start;
3022         ext4_fsblk_t len;
3023         int hblock, blocksize;
3024         ext4_fsblk_t sb_block;
3025         unsigned long offset;
3026         struct ext4_super_block *es;
3027         struct block_device *bdev;
3028
3029         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3030
3031         bdev = ext4_blkdev_get(j_dev, sb);
3032         if (bdev == NULL)
3033                 return NULL;
3034
3035         if (bd_claim(bdev, sb)) {
3036                 ext4_msg(sb, KERN_ERR,
3037                         "failed to claim external journal device");
3038                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3039                 return NULL;
3040         }
3041
3042         blocksize = sb->s_blocksize;
3043         hblock = bdev_logical_block_size(bdev);
3044         if (blocksize < hblock) {
3045                 ext4_msg(sb, KERN_ERR,
3046                         "blocksize too small for journal device");
3047                 goto out_bdev;
3048         }
3049
3050         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3051         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3052         set_blocksize(bdev, blocksize);
3053         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3054                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3055                        "external journal");
3056                 goto out_bdev;
3057         }
3058
3059         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3060         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3061             !(le32_to_cpu(es->s_feature_incompat) &
3062               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3063                 ext4_msg(sb, KERN_ERR, "external journal has "
3064                                         "bad superblock");
3065                 brelse(bh);
3066                 goto out_bdev;
3067         }
3068
3069         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3070                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3071                 brelse(bh);
3072                 goto out_bdev;
3073         }
3074
3075         len = ext4_blocks_count(es);
3076         start = sb_block + 1;
3077         brelse(bh);     /* we're done with the superblock */
3078
3079         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3080                                         start, len, blocksize);
3081         if (!journal) {
3082                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3083                 goto out_bdev;
3084         }
3085         journal->j_private = sb;
3086         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3087         wait_on_buffer(journal->j_sb_buffer);
3088         if (!buffer_uptodate(journal->j_sb_buffer)) {
3089                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3090                 goto out_journal;
3091         }
3092         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3093                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3094                                         "user (unsupported) - %d",
3095                         be32_to_cpu(journal->j_superblock->s_nr_users));
3096                 goto out_journal;
3097         }
3098         EXT4_SB(sb)->journal_bdev = bdev;
3099         ext4_init_journal_params(sb, journal);
3100         return journal;
3101
3102 out_journal:
3103         jbd2_journal_destroy(journal);
3104 out_bdev:
3105         ext4_blkdev_put(bdev);
3106         return NULL;
3107 }
3108
3109 static int ext4_load_journal(struct super_block *sb,
3110                              struct ext4_super_block *es,
3111                              unsigned long journal_devnum)
3112 {
3113         journal_t *journal;
3114         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3115         dev_t journal_dev;
3116         int err = 0;
3117         int really_read_only;
3118
3119         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3120
3121         if (journal_devnum &&
3122             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3123                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3124                         "numbers have changed");
3125                 journal_dev = new_decode_dev(journal_devnum);
3126         } else
3127                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3128
3129         really_read_only = bdev_read_only(sb->s_bdev);
3130
3131         /*
3132          * Are we loading a blank journal or performing recovery after a
3133          * crash?  For recovery, we need to check in advance whether we
3134          * can get read-write access to the device.
3135          */
3136         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3137                 if (sb->s_flags & MS_RDONLY) {
3138                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3139                                         "required on readonly filesystem");
3140                         if (really_read_only) {
3141                                 ext4_msg(sb, KERN_ERR, "write access "
3142                                         "unavailable, cannot proceed");
3143                                 return -EROFS;
3144                         }
3145                         ext4_msg(sb, KERN_INFO, "write access will "
3146                                "be enabled during recovery");
3147                 }
3148         }
3149
3150         if (journal_inum && journal_dev) {
3151                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3152                        "and inode journals!");
3153                 return -EINVAL;
3154         }
3155
3156         if (journal_inum) {
3157                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3158                         return -EINVAL;
3159         } else {
3160                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3161                         return -EINVAL;
3162         }
3163
3164         if (journal->j_flags & JBD2_BARRIER)
3165                 ext4_msg(sb, KERN_INFO, "barriers enabled");
3166         else
3167                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3168
3169         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3170                 err = jbd2_journal_update_format(journal);
3171                 if (err)  {
3172                         ext4_msg(sb, KERN_ERR, "error updating journal");
3173                         jbd2_journal_destroy(journal);
3174                         return err;
3175                 }
3176         }
3177
3178         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3179                 err = jbd2_journal_wipe(journal, !really_read_only);
3180         if (!err)
3181                 err = jbd2_journal_load(journal);
3182
3183         if (err) {
3184                 ext4_msg(sb, KERN_ERR, "error loading journal");
3185                 jbd2_journal_destroy(journal);
3186                 return err;
3187         }
3188
3189         EXT4_SB(sb)->s_journal = journal;
3190         ext4_clear_journal_err(sb, es);
3191
3192         if (journal_devnum &&
3193             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3194                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3195
3196                 /* Make sure we flush the recovery flag to disk. */
3197                 ext4_commit_super(sb, 1);
3198         }
3199
3200         return 0;
3201 }
3202
3203 static int ext4_commit_super(struct super_block *sb, int sync)
3204 {
3205         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3206         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3207         int error = 0;
3208
3209         if (!sbh)
3210                 return error;
3211         if (buffer_write_io_error(sbh)) {
3212                 /*
3213                  * Oh, dear.  A previous attempt to write the
3214                  * superblock failed.  This could happen because the
3215                  * USB device was yanked out.  Or it could happen to
3216                  * be a transient write error and maybe the block will
3217                  * be remapped.  Nothing we can do but to retry the
3218                  * write and hope for the best.
3219                  */
3220                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3221                        "superblock detected");
3222                 clear_buffer_write_io_error(sbh);
3223                 set_buffer_uptodate(sbh);
3224         }
3225         es->s_wtime = cpu_to_le32(get_seconds());
3226         es->s_kbytes_written =
3227                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3228                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3229                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3230         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3231                                         &EXT4_SB(sb)->s_freeblocks_counter));
3232         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3233                                         &EXT4_SB(sb)->s_freeinodes_counter));
3234         sb->s_dirt = 0;
3235         BUFFER_TRACE(sbh, "marking dirty");
3236         mark_buffer_dirty(sbh);
3237         if (sync) {
3238                 error = sync_dirty_buffer(sbh);
3239                 if (error)
3240                         return error;
3241
3242                 error = buffer_write_io_error(sbh);
3243                 if (error) {
3244                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3245                                "superblock");
3246                         clear_buffer_write_io_error(sbh);
3247                         set_buffer_uptodate(sbh);
3248                 }
3249         }
3250         return error;
3251 }
3252
3253 /*
3254  * Have we just finished recovery?  If so, and if we are mounting (or
3255  * remounting) the filesystem readonly, then we will end up with a
3256  * consistent fs on disk.  Record that fact.
3257  */
3258 static void ext4_mark_recovery_complete(struct super_block *sb,
3259                                         struct ext4_super_block *es)
3260 {
3261         journal_t *journal = EXT4_SB(sb)->s_journal;
3262
3263         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3264                 BUG_ON(journal != NULL);
3265                 return;
3266         }
3267         jbd2_journal_lock_updates(journal);
3268         if (jbd2_journal_flush(journal) < 0)
3269                 goto out;
3270
3271         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3272             sb->s_flags & MS_RDONLY) {
3273                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3274                 ext4_commit_super(sb, 1);
3275         }
3276
3277 out:
3278         jbd2_journal_unlock_updates(journal);
3279 }
3280
3281 /*
3282  * If we are mounting (or read-write remounting) a filesystem whose journal
3283  * has recorded an error from a previous lifetime, move that error to the
3284  * main filesystem now.
3285  */
3286 static void ext4_clear_journal_err(struct super_block *sb,
3287                                    struct ext4_super_block *es)
3288 {
3289         journal_t *journal;
3290         int j_errno;
3291         const char *errstr;
3292
3293         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3294
3295         journal = EXT4_SB(sb)->s_journal;
3296
3297         /*
3298          * Now check for any error status which may have been recorded in the
3299          * journal by a prior ext4_error() or ext4_abort()
3300          */
3301
3302         j_errno = jbd2_journal_errno(journal);
3303         if (j_errno) {
3304                 char nbuf[16];
3305
3306                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3307                 ext4_warning(sb, __func__, "Filesystem error recorded "
3308                              "from previous mount: %s", errstr);
3309                 ext4_warning(sb, __func__, "Marking fs in need of "
3310                              "filesystem check.");
3311
3312                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3313                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3314                 ext4_commit_super(sb, 1);
3315
3316                 jbd2_journal_clear_err(journal);
3317         }
3318 }
3319
3320 /*
3321  * Force the running and committing transactions to commit,
3322  * and wait on the commit.
3323  */
3324 int ext4_force_commit(struct super_block *sb)
3325 {
3326         journal_t *journal;
3327         int ret = 0;
3328
3329         if (sb->s_flags & MS_RDONLY)
3330                 return 0;
3331
3332         journal = EXT4_SB(sb)->s_journal;
3333         if (journal)
3334                 ret = ext4_journal_force_commit(journal);
3335
3336         return ret;
3337 }
3338
3339 static void ext4_write_super(struct super_block *sb)
3340 {
3341         lock_super(sb);
3342         ext4_commit_super(sb, 1);
3343         unlock_super(sb);
3344 }
3345
3346 static int ext4_sync_fs(struct super_block *sb, int wait)
3347 {
3348         int ret = 0;
3349         tid_t target;
3350
3351         trace_ext4_sync_fs(sb, wait);
3352         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
3353                 if (wait)
3354                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
3355         }
3356         return ret;
3357 }
3358
3359 /*
3360  * LVM calls this function before a (read-only) snapshot is created.  This
3361  * gives us a chance to flush the journal completely and mark the fs clean.
3362  */
3363 static int ext4_freeze(struct super_block *sb)
3364 {
3365         int error = 0;
3366         journal_t *journal;
3367
3368         if (sb->s_flags & MS_RDONLY)
3369                 return 0;
3370
3371         journal = EXT4_SB(sb)->s_journal;
3372
3373         /* Now we set up the journal barrier. */
3374         jbd2_journal_lock_updates(journal);
3375
3376         /*
3377          * Don't clear the needs_recovery flag if we failed to flush
3378          * the journal.
3379          */
3380         error = jbd2_journal_flush(journal);
3381         if (error < 0) {
3382         out:
3383                 jbd2_journal_unlock_updates(journal);
3384                 return error;
3385         }
3386
3387         /* Journal blocked and flushed, clear needs_recovery flag. */
3388         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3389         error = ext4_commit_super(sb, 1);
3390         if (error)
3391                 goto out;
3392         return 0;
3393 }
3394
3395 /*
3396  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3397  * flag here, even though the filesystem is not technically dirty yet.
3398  */
3399 static int ext4_unfreeze(struct super_block *sb)
3400 {
3401         if (sb->s_flags & MS_RDONLY)
3402                 return 0;
3403
3404         lock_super(sb);
3405         /* Reset the needs_recovery flag before the fs is unlocked. */
3406         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3407         ext4_commit_super(sb, 1);
3408         unlock_super(sb);
3409         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3410         return 0;
3411 }
3412
3413 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3414 {
3415         struct ext4_super_block *es;
3416         struct ext4_sb_info *sbi = EXT4_SB(sb);
3417         ext4_fsblk_t n_blocks_count = 0;
3418         unsigned long old_sb_flags;
3419         struct ext4_mount_options old_opts;
3420         ext4_group_t g;
3421         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3422         int err;
3423 #ifdef CONFIG_QUOTA
3424         int i;
3425 #endif
3426
3427         lock_kernel();
3428
3429         /* Store the original options */
3430         lock_super(sb);
3431         old_sb_flags = sb->s_flags;
3432         old_opts.s_mount_opt = sbi->s_mount_opt;
3433         old_opts.s_resuid = sbi->s_resuid;
3434         old_opts.s_resgid = sbi->s_resgid;
3435         old_opts.s_commit_interval = sbi->s_commit_interval;
3436         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3437         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3438 #ifdef CONFIG_QUOTA
3439         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3440         for (i = 0; i < MAXQUOTAS; i++)
3441                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3442 #endif
3443         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3444                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3445
3446         /*
3447          * Allow the "check" option to be passed as a remount option.
3448          */
3449         if (!parse_options(data, sb, NULL, &journal_ioprio,
3450                            &n_blocks_count, 1)) {
3451                 err = -EINVAL;
3452                 goto restore_opts;
3453         }
3454
3455         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
3456                 ext4_abort(sb, __func__, "Abort forced by user");
3457
3458         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3459                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3460
3461         es = sbi->s_es;
3462
3463         if (sbi->s_journal) {
3464                 ext4_init_journal_params(sb, sbi->s_journal);
3465                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3466         }
3467
3468         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3469                 n_blocks_count > ext4_blocks_count(es)) {
3470                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3471                         err = -EROFS;
3472                         goto restore_opts;
3473                 }
3474
3475                 if (*flags & MS_RDONLY) {
3476                         /*
3477                          * First of all, the unconditional stuff we have to do
3478                          * to disable replay of the journal when we next remount
3479                          */
3480                         sb->s_flags |= MS_RDONLY;
3481
3482                         /*
3483                          * OK, test if we are remounting a valid rw partition
3484                          * readonly, and if so set the rdonly flag and then
3485                          * mark the partition as valid again.
3486                          */
3487                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3488                             (sbi->s_mount_state & EXT4_VALID_FS))
3489                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3490
3491                         if (sbi->s_journal)
3492                                 ext4_mark_recovery_complete(sb, es);
3493                 } else {
3494                         int ret;
3495                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3496                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3497                                 ext4_msg(sb, KERN_WARNING, "couldn't "
3498                                        "remount RDWR because of unsupported "
3499                                        "optional features (%x)",
3500                                 (le32_to_cpu(sbi->s_es->s_feature_ro_compat) &
3501                                         ~EXT4_FEATURE_RO_COMPAT_SUPP));
3502                                 err = -EROFS;
3503                                 goto restore_opts;
3504                         }
3505
3506                         /*
3507                          * Make sure the group descriptor checksums
3508                          * are sane.  If they aren't, refuse to remount r/w.
3509                          */
3510                         for (g = 0; g < sbi->s_groups_count; g++) {
3511                                 struct ext4_group_desc *gdp =
3512                                         ext4_get_group_desc(sb, g, NULL);
3513
3514                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3515                                         ext4_msg(sb, KERN_ERR,
3516                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3517                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3518                                                le16_to_cpu(gdp->bg_checksum));
3519                                         err = -EINVAL;
3520                                         goto restore_opts;
3521                                 }
3522                         }
3523
3524                         /*
3525                          * If we have an unprocessed orphan list hanging
3526                          * around from a previously readonly bdev mount,
3527                          * require a full umount/remount for now.
3528                          */
3529                         if (es->s_last_orphan) {
3530                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3531                                        "remount RDWR because of unprocessed "
3532                                        "orphan inode list.  Please "
3533                                        "umount/remount instead");
3534                                 err = -EINVAL;
3535                                 goto restore_opts;
3536                         }
3537
3538                         /*
3539                          * Mounting a RDONLY partition read-write, so reread
3540                          * and store the current valid flag.  (It may have
3541                          * been changed by e2fsck since we originally mounted
3542                          * the partition.)
3543                          */
3544                         if (sbi->s_journal)
3545                                 ext4_clear_journal_err(sb, es);
3546                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3547                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3548                                 goto restore_opts;
3549                         if (!ext4_setup_super(sb, es, 0))
3550                                 sb->s_flags &= ~MS_RDONLY;
3551                 }
3552         }
3553         ext4_setup_system_zone(sb);
3554         if (sbi->s_journal == NULL)
3555                 ext4_commit_super(sb, 1);
3556
3557 #ifdef CONFIG_QUOTA
3558         /* Release old quota file names */
3559         for (i = 0; i < MAXQUOTAS; i++)
3560                 if (old_opts.s_qf_names[i] &&
3561                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3562                         kfree(old_opts.s_qf_names[i]);
3563 #endif
3564         unlock_super(sb);
3565         unlock_kernel();
3566         return 0;
3567
3568 restore_opts:
3569         sb->s_flags = old_sb_flags;
3570         sbi->s_mount_opt = old_opts.s_mount_opt;
3571         sbi->s_resuid = old_opts.s_resuid;
3572         sbi->s_resgid = old_opts.s_resgid;
3573         sbi->s_commit_interval = old_opts.s_commit_interval;
3574         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3575         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3576 #ifdef CONFIG_QUOTA
3577         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3578         for (i = 0; i < MAXQUOTAS; i++) {
3579                 if (sbi->s_qf_names[i] &&
3580                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3581                         kfree(sbi->s_qf_names[i]);
3582                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3583         }
3584 #endif
3585         unlock_super(sb);
3586         unlock_kernel();
3587         return err;
3588 }
3589
3590 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3591 {
3592         struct super_block *sb = dentry->d_sb;
3593         struct ext4_sb_info *sbi = EXT4_SB(sb);
3594         struct ext4_super_block *es = sbi->s_es;
3595         u64 fsid;
3596
3597         if (test_opt(sb, MINIX_DF)) {
3598                 sbi->s_overhead_last = 0;
3599         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3600                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3601                 ext4_fsblk_t overhead = 0;
3602
3603                 /*
3604                  * Compute the overhead (FS structures).  This is constant
3605                  * for a given filesystem unless the number of block groups
3606                  * changes so we cache the previous value until it does.
3607                  */
3608
3609                 /*
3610                  * All of the blocks before first_data_block are
3611                  * overhead
3612                  */
3613                 overhead = le32_to_cpu(es->s_first_data_block);
3614
3615                 /*
3616                  * Add the overhead attributed to the superblock and
3617                  * block group descriptors.  If the sparse superblocks
3618                  * feature is turned on, then not all groups have this.
3619                  */
3620                 for (i = 0; i < ngroups; i++) {
3621                         overhead += ext4_bg_has_super(sb, i) +
3622                                 ext4_bg_num_gdb(sb, i);
3623                         cond_resched();
3624                 }
3625
3626                 /*
3627                  * Every block group has an inode bitmap, a block
3628                  * bitmap, and an inode table.
3629                  */
3630                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3631                 sbi->s_overhead_last = overhead;
3632                 smp_wmb();
3633                 sbi->s_blocks_last = ext4_blocks_count(es);
3634         }
3635
3636         buf->f_type = EXT4_SUPER_MAGIC;
3637         buf->f_bsize = sb->s_blocksize;
3638         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3639         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3640                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3641         ext4_free_blocks_count_set(es, buf->f_bfree);
3642         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3643         if (buf->f_bfree < ext4_r_blocks_count(es))
3644                 buf->f_bavail = 0;
3645         buf->f_files = le32_to_cpu(es->s_inodes_count);
3646         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3647         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3648         buf->f_namelen = EXT4_NAME_LEN;
3649         fsid = le64_to_cpup((void *)es->s_uuid) ^
3650                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3651         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3652         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3653
3654         return 0;
3655 }
3656
3657 /* Helper function for writing quotas on sync - we need to start transaction
3658  * before quota file is locked for write. Otherwise the are possible deadlocks:
3659  * Process 1                         Process 2
3660  * ext4_create()                     quota_sync()
3661  *   jbd2_journal_start()                  write_dquot()
3662  *   vfs_dq_init()                         down(dqio_mutex)
3663  *     down(dqio_mutex)                    jbd2_journal_start()
3664  *
3665  */
3666
3667 #ifdef CONFIG_QUOTA
3668
3669 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3670 {
3671         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3672 }
3673
3674 static int ext4_write_dquot(struct dquot *dquot)
3675 {
3676         int ret, err;
3677         handle_t *handle;
3678         struct inode *inode;
3679
3680         inode = dquot_to_inode(dquot);
3681         handle = ext4_journal_start(inode,
3682                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3683         if (IS_ERR(handle))
3684                 return PTR_ERR(handle);
3685         ret = dquot_commit(dquot);
3686         err = ext4_journal_stop(handle);
3687         if (!ret)
3688                 ret = err;
3689         return ret;
3690 }
3691
3692 static int ext4_acquire_dquot(struct dquot *dquot)
3693 {
3694         int ret, err;
3695         handle_t *handle;
3696
3697         handle = ext4_journal_start(dquot_to_inode(dquot),
3698                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3699         if (IS_ERR(handle))
3700                 return PTR_ERR(handle);
3701         ret = dquot_acquire(dquot);
3702         err = ext4_journal_stop(handle);
3703         if (!ret)
3704                 ret = err;
3705         return ret;
3706 }
3707
3708 static int ext4_release_dquot(struct dquot *dquot)
3709 {
3710         int ret, err;
3711         handle_t *handle;
3712
3713         handle = ext4_journal_start(dquot_to_inode(dquot),
3714                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3715         if (IS_ERR(handle)) {
3716                 /* Release dquot anyway to avoid endless cycle in dqput() */
3717                 dquot_release(dquot);
3718                 return PTR_ERR(handle);
3719         }
3720         ret = dquot_release(dquot);
3721         err = ext4_journal_stop(handle);
3722         if (!ret)
3723                 ret = err;
3724         return ret;
3725 }
3726
3727 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3728 {
3729         /* Are we journaling quotas? */
3730         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3731             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3732                 dquot_mark_dquot_dirty(dquot);
3733                 return ext4_write_dquot(dquot);
3734         } else {
3735                 return dquot_mark_dquot_dirty(dquot);
3736         }
3737 }
3738
3739 static int ext4_write_info(struct super_block *sb, int type)
3740 {
3741         int ret, err;
3742         handle_t *handle;
3743
3744         /* Data block + inode block */
3745         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3746         if (IS_ERR(handle))
3747                 return PTR_ERR(handle);
3748         ret = dquot_commit_info(sb, type);
3749         err = ext4_journal_stop(handle);
3750         if (!ret)
3751                 ret = err;
3752         return ret;
3753 }
3754
3755 /*
3756  * Turn on quotas during mount time - we need to find
3757  * the quota file and such...
3758  */
3759 static int ext4_quota_on_mount(struct super_block *sb, int type)
3760 {
3761         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3762                                   EXT4_SB(sb)->s_jquota_fmt, type);
3763 }
3764
3765 /*
3766  * Standard function to be called on quota_on
3767  */
3768 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3769                          char *name, int remount)
3770 {
3771         int err;
3772         struct path path;
3773
3774         if (!test_opt(sb, QUOTA))
3775                 return -EINVAL;
3776         /* When remounting, no checks are needed and in fact, name is NULL */
3777         if (remount)
3778                 return vfs_quota_on(sb, type, format_id, name, remount);
3779
3780         err = kern_path(name, LOOKUP_FOLLOW, &path);
3781         if (err)
3782                 return err;
3783
3784         /* Quotafile not on the same filesystem? */
3785         if (path.mnt->mnt_sb != sb) {
3786                 path_put(&path);
3787                 return -EXDEV;
3788         }
3789         /* Journaling quota? */
3790         if (EXT4_SB(sb)->s_qf_names[type]) {
3791                 /* Quotafile not in fs root? */
3792                 if (path.dentry->d_parent != sb->s_root)
3793                         ext4_msg(sb, KERN_WARNING,
3794                                 "Quota file not on filesystem root. "
3795                                 "Journaled quota will not work");
3796         }
3797
3798         /*
3799          * When we journal data on quota file, we have to flush journal to see
3800          * all updates to the file when we bypass pagecache...
3801          */
3802         if (EXT4_SB(sb)->s_journal &&
3803             ext4_should_journal_data(path.dentry->d_inode)) {
3804                 /*
3805                  * We don't need to lock updates but journal_flush() could
3806                  * otherwise be livelocked...
3807                  */
3808                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3809                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3810                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3811                 if (err) {
3812                         path_put(&path);
3813                         return err;
3814                 }
3815         }
3816
3817         err = vfs_quota_on_path(sb, type, format_id, &path);
3818         path_put(&path);
3819         return err;
3820 }
3821
3822 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3823  * acquiring the locks... As quota files are never truncated and quota code
3824  * itself serializes the operations (and noone else should touch the files)
3825  * we don't have to be afraid of races */
3826 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3827                                size_t len, loff_t off)
3828 {
3829         struct inode *inode = sb_dqopt(sb)->files[type];
3830         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3831         int err = 0;
3832         int offset = off & (sb->s_blocksize - 1);
3833         int tocopy;
3834         size_t toread;
3835         struct buffer_head *bh;
3836         loff_t i_size = i_size_read(inode);
3837
3838         if (off > i_size)
3839                 return 0;
3840         if (off+len > i_size)
3841                 len = i_size-off;
3842         toread = len;
3843         while (toread > 0) {
3844                 tocopy = sb->s_blocksize - offset < toread ?
3845                                 sb->s_blocksize - offset : toread;
3846                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3847                 if (err)
3848                         return err;
3849                 if (!bh)        /* A hole? */
3850                         memset(data, 0, tocopy);
3851                 else
3852                         memcpy(data, bh->b_data+offset, tocopy);
3853                 brelse(bh);
3854                 offset = 0;
3855                 toread -= tocopy;
3856                 data += tocopy;
3857                 blk++;
3858         }
3859         return len;
3860 }
3861
3862 /* Write to quotafile (we know the transaction is already started and has
3863  * enough credits) */
3864 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3865                                 const char *data, size_t len, loff_t off)
3866 {
3867         struct inode *inode = sb_dqopt(sb)->files[type];
3868         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3869         int err = 0;
3870         int offset = off & (sb->s_blocksize - 1);
3871         int tocopy;
3872         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3873         size_t towrite = len;
3874         struct buffer_head *bh;
3875         handle_t *handle = journal_current_handle();
3876
3877         if (EXT4_SB(sb)->s_journal && !handle) {
3878                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3879                         " cancelled because transaction is not started",
3880                         (unsigned long long)off, (unsigned long long)len);
3881                 return -EIO;
3882         }
3883         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3884         while (towrite > 0) {
3885                 tocopy = sb->s_blocksize - offset < towrite ?
3886                                 sb->s_blocksize - offset : towrite;
3887                 bh = ext4_bread(handle, inode, blk, 1, &err);
3888                 if (!bh)
3889                         goto out;
3890                 if (journal_quota) {
3891                         err = ext4_journal_get_write_access(handle, bh);
3892                         if (err) {
3893                                 brelse(bh);
3894                                 goto out;
3895                         }
3896                 }
3897                 lock_buffer(bh);
3898                 memcpy(bh->b_data+offset, data, tocopy);
3899                 flush_dcache_page(bh->b_page);
3900                 unlock_buffer(bh);
3901                 if (journal_quota)
3902                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3903                 else {
3904                         /* Always do at least ordered writes for quotas */
3905                         err = ext4_jbd2_file_inode(handle, inode);
3906                         mark_buffer_dirty(bh);
3907                 }
3908                 brelse(bh);
3909                 if (err)
3910                         goto out;
3911                 offset = 0;
3912                 towrite -= tocopy;
3913                 data += tocopy;
3914                 blk++;
3915         }
3916 out:
3917         if (len == towrite) {
3918                 mutex_unlock(&inode->i_mutex);
3919                 return err;
3920         }
3921         if (inode->i_size < off+len-towrite) {
3922                 i_size_write(inode, off+len-towrite);
3923                 EXT4_I(inode)->i_disksize = inode->i_size;
3924         }
3925         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3926         ext4_mark_inode_dirty(handle, inode);
3927         mutex_unlock(&inode->i_mutex);
3928         return len - towrite;
3929 }
3930
3931 #endif
3932
3933 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3934                        const char *dev_name, void *data, struct vfsmount *mnt)
3935 {
3936         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3937 }
3938
3939 static struct file_system_type ext4_fs_type = {
3940         .owner          = THIS_MODULE,
3941         .name           = "ext4",
3942         .get_sb         = ext4_get_sb,
3943         .kill_sb        = kill_block_super,
3944         .fs_flags       = FS_REQUIRES_DEV,
3945 };
3946
3947 #ifdef CONFIG_EXT4DEV_COMPAT
3948 static int ext4dev_get_sb(struct file_system_type *fs_type, int flags,
3949                           const char *dev_name, void *data,struct vfsmount *mnt)
3950 {
3951         printk(KERN_WARNING "EXT4-fs (%s): Update your userspace programs "
3952                "to mount using ext4\n", dev_name);
3953         printk(KERN_WARNING "EXT4-fs (%s): ext4dev backwards compatibility "
3954                "will go away by 2.6.31\n", dev_name);
3955         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3956 }
3957
3958 static struct file_system_type ext4dev_fs_type = {
3959         .owner          = THIS_MODULE,
3960         .name           = "ext4dev",
3961         .get_sb         = ext4dev_get_sb,
3962         .kill_sb        = kill_block_super,
3963         .fs_flags       = FS_REQUIRES_DEV,
3964 };
3965 MODULE_ALIAS("ext4dev");
3966 #endif
3967
3968 static int __init init_ext4_fs(void)
3969 {
3970         int err;
3971
3972         err = init_ext4_system_zone();
3973         if (err)
3974                 return err;
3975         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
3976         if (!ext4_kset)
3977                 goto out4;
3978         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
3979         err = init_ext4_mballoc();
3980         if (err)
3981                 goto out3;
3982
3983         err = init_ext4_xattr();
3984         if (err)
3985                 goto out2;
3986         err = init_inodecache();
3987         if (err)
3988                 goto out1;
3989         err = register_filesystem(&ext4_fs_type);
3990         if (err)
3991                 goto out;
3992 #ifdef CONFIG_EXT4DEV_COMPAT
3993         err = register_filesystem(&ext4dev_fs_type);
3994         if (err) {
3995                 unregister_filesystem(&ext4_fs_type);
3996                 goto out;
3997         }
3998 #endif
3999         return 0;
4000 out:
4001         destroy_inodecache();
4002 out1:
4003         exit_ext4_xattr();
4004 out2:
4005         exit_ext4_mballoc();
4006 out3:
4007         remove_proc_entry("fs/ext4", NULL);
4008         kset_unregister(ext4_kset);
4009 out4:
4010         exit_ext4_system_zone();
4011         return err;
4012 }
4013
4014 static void __exit exit_ext4_fs(void)
4015 {
4016         unregister_filesystem(&ext4_fs_type);
4017 #ifdef CONFIG_EXT4DEV_COMPAT
4018         unregister_filesystem(&ext4dev_fs_type);
4019 #endif
4020         destroy_inodecache();
4021         exit_ext4_xattr();
4022         exit_ext4_mballoc();
4023         remove_proc_entry("fs/ext4", NULL);
4024         kset_unregister(ext4_kset);
4025         exit_ext4_system_zone();
4026 }
4027
4028 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4029 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4030 MODULE_LICENSE("GPL");
4031 module_init(init_ext4_fs)
4032 module_exit(exit_ext4_fs)